23 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
24 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
25 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
26 #define SSH1_CMSG_USER 4 /* 0x4 */
27 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
28 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
29 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
30 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
31 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
32 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
33 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
34 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
35 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
36 #define SSH1_SMSG_FAILURE 15 /* 0xf */
37 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
38 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
39 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
40 #define SSH1_CMSG_EOF 19 /* 0x13 */
41 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
42 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
43 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
44 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
45 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
46 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
47 #define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
48 #define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
49 #define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
50 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
51 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
52 #define SSH1_MSG_IGNORE 32 /* 0x20 */
53 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
54 #define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
55 #define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
56 #define SSH1_MSG_DEBUG 36 /* 0x24 */
57 #define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
58 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
59 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
60 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
61 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
62 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
63 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
65 #define SSH1_AUTH_TIS 5 /* 0x5 */
66 #define SSH1_AUTH_CCARD 16 /* 0x10 */
68 #define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
69 /* Mask for protoflags we will echo back to server if seen */
70 #define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
72 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
73 #define SSH2_MSG_IGNORE 2 /* 0x2 */
74 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
75 #define SSH2_MSG_DEBUG 4 /* 0x4 */
76 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
77 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
78 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
79 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
80 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
81 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
82 #define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
83 #define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
84 #define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
85 #define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
86 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
87 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
88 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
89 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
90 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
91 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
92 #define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
93 #define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
94 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
95 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
96 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
97 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
98 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
99 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
100 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
101 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
102 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
103 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
104 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
105 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
106 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
107 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
110 * Packet type contexts, so that ssh2_pkt_type can correctly decode
111 * the ambiguous type numbers back into the correct type strings.
113 #define SSH2_PKTCTX_DHGROUP 0x0001
114 #define SSH2_PKTCTX_DHGEX 0x0002
115 #define SSH2_PKTCTX_KEX_MASK 0x000F
116 #define SSH2_PKTCTX_PUBLICKEY 0x0010
117 #define SSH2_PKTCTX_PASSWORD 0x0020
118 #define SSH2_PKTCTX_KBDINTER 0x0040
119 #define SSH2_PKTCTX_AUTH_MASK 0x00F0
121 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
122 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
123 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
124 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
125 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
126 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
127 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
128 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
129 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
130 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
131 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
132 #define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
133 #define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
134 #define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
135 #define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
137 static const char *const ssh2_disconnect_reasons
[] = {
139 "host not allowed to connect",
141 "key exchange failed",
142 "host authentication failed",
145 "service not available",
146 "protocol version not supported",
147 "host key not verifiable",
150 "too many connections",
151 "auth cancelled by user",
152 "no more auth methods available",
156 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
157 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
158 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
159 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
161 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
164 * Various remote-bug flags.
166 #define BUG_CHOKES_ON_SSH1_IGNORE 1
167 #define BUG_SSH2_HMAC 2
168 #define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
169 #define BUG_CHOKES_ON_RSA 8
170 #define BUG_SSH2_RSA_PADDING 16
171 #define BUG_SSH2_DERIVEKEY 32
172 #define BUG_SSH2_REKEY 64
173 #define BUG_SSH2_PK_SESSIONID 128
176 * Codes for terminal modes.
177 * Most of these are the same in SSH-1 and SSH-2.
178 * This list is derived from draft-ietf-secsh-connect-25 and
181 static const struct {
182 const char* const mode
;
184 enum { TTY_OP_CHAR
, TTY_OP_BOOL
} type
;
186 /* "V" prefix discarded for special characters relative to SSH specs */
187 { "INTR", 1, TTY_OP_CHAR
},
188 { "QUIT", 2, TTY_OP_CHAR
},
189 { "ERASE", 3, TTY_OP_CHAR
},
190 { "KILL", 4, TTY_OP_CHAR
},
191 { "EOF", 5, TTY_OP_CHAR
},
192 { "EOL", 6, TTY_OP_CHAR
},
193 { "EOL2", 7, TTY_OP_CHAR
},
194 { "START", 8, TTY_OP_CHAR
},
195 { "STOP", 9, TTY_OP_CHAR
},
196 { "SUSP", 10, TTY_OP_CHAR
},
197 { "DSUSP", 11, TTY_OP_CHAR
},
198 { "REPRINT", 12, TTY_OP_CHAR
},
199 { "WERASE", 13, TTY_OP_CHAR
},
200 { "LNEXT", 14, TTY_OP_CHAR
},
201 { "FLUSH", 15, TTY_OP_CHAR
},
202 { "SWTCH", 16, TTY_OP_CHAR
},
203 { "STATUS", 17, TTY_OP_CHAR
},
204 { "DISCARD", 18, TTY_OP_CHAR
},
205 { "IGNPAR", 30, TTY_OP_BOOL
},
206 { "PARMRK", 31, TTY_OP_BOOL
},
207 { "INPCK", 32, TTY_OP_BOOL
},
208 { "ISTRIP", 33, TTY_OP_BOOL
},
209 { "INLCR", 34, TTY_OP_BOOL
},
210 { "IGNCR", 35, TTY_OP_BOOL
},
211 { "ICRNL", 36, TTY_OP_BOOL
},
212 { "IUCLC", 37, TTY_OP_BOOL
},
213 { "IXON", 38, TTY_OP_BOOL
},
214 { "IXANY", 39, TTY_OP_BOOL
},
215 { "IXOFF", 40, TTY_OP_BOOL
},
216 { "IMAXBEL", 41, TTY_OP_BOOL
},
217 { "ISIG", 50, TTY_OP_BOOL
},
218 { "ICANON", 51, TTY_OP_BOOL
},
219 { "XCASE", 52, TTY_OP_BOOL
},
220 { "ECHO", 53, TTY_OP_BOOL
},
221 { "ECHOE", 54, TTY_OP_BOOL
},
222 { "ECHOK", 55, TTY_OP_BOOL
},
223 { "ECHONL", 56, TTY_OP_BOOL
},
224 { "NOFLSH", 57, TTY_OP_BOOL
},
225 { "TOSTOP", 58, TTY_OP_BOOL
},
226 { "IEXTEN", 59, TTY_OP_BOOL
},
227 { "ECHOCTL", 60, TTY_OP_BOOL
},
228 { "ECHOKE", 61, TTY_OP_BOOL
},
229 { "PENDIN", 62, TTY_OP_BOOL
}, /* XXX is this a real mode? */
230 { "OPOST", 70, TTY_OP_BOOL
},
231 { "OLCUC", 71, TTY_OP_BOOL
},
232 { "ONLCR", 72, TTY_OP_BOOL
},
233 { "OCRNL", 73, TTY_OP_BOOL
},
234 { "ONOCR", 74, TTY_OP_BOOL
},
235 { "ONLRET", 75, TTY_OP_BOOL
},
236 { "CS7", 90, TTY_OP_BOOL
},
237 { "CS8", 91, TTY_OP_BOOL
},
238 { "PARENB", 92, TTY_OP_BOOL
},
239 { "PARODD", 93, TTY_OP_BOOL
}
242 /* Miscellaneous other tty-related constants. */
243 #define SSH_TTY_OP_END 0
244 /* The opcodes for ISPEED/OSPEED differ between SSH-1 and SSH-2. */
245 #define SSH1_TTY_OP_ISPEED 192
246 #define SSH1_TTY_OP_OSPEED 193
247 #define SSH2_TTY_OP_ISPEED 128
248 #define SSH2_TTY_OP_OSPEED 129
250 /* Helper functions for parsing tty-related config. */
251 static unsigned int ssh_tty_parse_specchar(char *s
)
256 ret
= ctrlparse(s
, &next
);
257 if (!next
) ret
= s
[0];
259 ret
= 255; /* special value meaning "don't set" */
263 static unsigned int ssh_tty_parse_boolean(char *s
)
265 if (stricmp(s
, "yes") == 0 ||
266 stricmp(s
, "on") == 0 ||
267 stricmp(s
, "true") == 0 ||
268 stricmp(s
, "+") == 0)
270 else if (stricmp(s
, "no") == 0 ||
271 stricmp(s
, "off") == 0 ||
272 stricmp(s
, "false") == 0 ||
273 stricmp(s
, "-") == 0)
274 return 0; /* false */
276 return (atoi(s
) != 0);
279 #define translate(x) if (type == x) return #x
280 #define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
281 static char *ssh1_pkt_type(int type
)
283 translate(SSH1_MSG_DISCONNECT
);
284 translate(SSH1_SMSG_PUBLIC_KEY
);
285 translate(SSH1_CMSG_SESSION_KEY
);
286 translate(SSH1_CMSG_USER
);
287 translate(SSH1_CMSG_AUTH_RSA
);
288 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE
);
289 translate(SSH1_CMSG_AUTH_RSA_RESPONSE
);
290 translate(SSH1_CMSG_AUTH_PASSWORD
);
291 translate(SSH1_CMSG_REQUEST_PTY
);
292 translate(SSH1_CMSG_WINDOW_SIZE
);
293 translate(SSH1_CMSG_EXEC_SHELL
);
294 translate(SSH1_CMSG_EXEC_CMD
);
295 translate(SSH1_SMSG_SUCCESS
);
296 translate(SSH1_SMSG_FAILURE
);
297 translate(SSH1_CMSG_STDIN_DATA
);
298 translate(SSH1_SMSG_STDOUT_DATA
);
299 translate(SSH1_SMSG_STDERR_DATA
);
300 translate(SSH1_CMSG_EOF
);
301 translate(SSH1_SMSG_EXIT_STATUS
);
302 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
);
303 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE
);
304 translate(SSH1_MSG_CHANNEL_DATA
);
305 translate(SSH1_MSG_CHANNEL_CLOSE
);
306 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
);
307 translate(SSH1_SMSG_X11_OPEN
);
308 translate(SSH1_CMSG_PORT_FORWARD_REQUEST
);
309 translate(SSH1_MSG_PORT_OPEN
);
310 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING
);
311 translate(SSH1_SMSG_AGENT_OPEN
);
312 translate(SSH1_MSG_IGNORE
);
313 translate(SSH1_CMSG_EXIT_CONFIRMATION
);
314 translate(SSH1_CMSG_X11_REQUEST_FORWARDING
);
315 translate(SSH1_CMSG_AUTH_RHOSTS_RSA
);
316 translate(SSH1_MSG_DEBUG
);
317 translate(SSH1_CMSG_REQUEST_COMPRESSION
);
318 translate(SSH1_CMSG_AUTH_TIS
);
319 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE
);
320 translate(SSH1_CMSG_AUTH_TIS_RESPONSE
);
321 translate(SSH1_CMSG_AUTH_CCARD
);
322 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE
);
323 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE
);
326 static char *ssh2_pkt_type(int pkt_ctx
, int type
)
328 translate(SSH2_MSG_DISCONNECT
);
329 translate(SSH2_MSG_IGNORE
);
330 translate(SSH2_MSG_UNIMPLEMENTED
);
331 translate(SSH2_MSG_DEBUG
);
332 translate(SSH2_MSG_SERVICE_REQUEST
);
333 translate(SSH2_MSG_SERVICE_ACCEPT
);
334 translate(SSH2_MSG_KEXINIT
);
335 translate(SSH2_MSG_NEWKEYS
);
336 translatec(SSH2_MSG_KEXDH_INIT
, SSH2_PKTCTX_DHGROUP
);
337 translatec(SSH2_MSG_KEXDH_REPLY
, SSH2_PKTCTX_DHGROUP
);
338 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST
, SSH2_PKTCTX_DHGEX
);
339 translatec(SSH2_MSG_KEX_DH_GEX_GROUP
, SSH2_PKTCTX_DHGEX
);
340 translatec(SSH2_MSG_KEX_DH_GEX_INIT
, SSH2_PKTCTX_DHGEX
);
341 translatec(SSH2_MSG_KEX_DH_GEX_REPLY
, SSH2_PKTCTX_DHGEX
);
342 translate(SSH2_MSG_USERAUTH_REQUEST
);
343 translate(SSH2_MSG_USERAUTH_FAILURE
);
344 translate(SSH2_MSG_USERAUTH_SUCCESS
);
345 translate(SSH2_MSG_USERAUTH_BANNER
);
346 translatec(SSH2_MSG_USERAUTH_PK_OK
, SSH2_PKTCTX_PUBLICKEY
);
347 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
, SSH2_PKTCTX_PASSWORD
);
348 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST
, SSH2_PKTCTX_KBDINTER
);
349 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE
, SSH2_PKTCTX_KBDINTER
);
350 translate(SSH2_MSG_GLOBAL_REQUEST
);
351 translate(SSH2_MSG_REQUEST_SUCCESS
);
352 translate(SSH2_MSG_REQUEST_FAILURE
);
353 translate(SSH2_MSG_CHANNEL_OPEN
);
354 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
355 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
356 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
357 translate(SSH2_MSG_CHANNEL_DATA
);
358 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA
);
359 translate(SSH2_MSG_CHANNEL_EOF
);
360 translate(SSH2_MSG_CHANNEL_CLOSE
);
361 translate(SSH2_MSG_CHANNEL_REQUEST
);
362 translate(SSH2_MSG_CHANNEL_SUCCESS
);
363 translate(SSH2_MSG_CHANNEL_FAILURE
);
369 /* Enumeration values for fields in SSH-1 packets */
371 PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
,
372 /* These values are for communicating relevant semantics of
373 * fields to the packet logging code. */
374 PKTT_OTHER
, PKTT_PASSWORD
, PKTT_DATA
378 * Coroutine mechanics for the sillier bits of the code. If these
379 * macros look impenetrable to you, you might find it helpful to
382 * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
384 * which explains the theory behind these macros.
386 * In particular, if you are getting `case expression not constant'
387 * errors when building with MS Visual Studio, this is because MS's
388 * Edit and Continue debugging feature causes their compiler to
389 * violate ANSI C. To disable Edit and Continue debugging:
391 * - right-click ssh.c in the FileView
393 * - select the C/C++ tab and the General category
394 * - under `Debug info:', select anything _other_ than `Program
395 * Database for Edit and Continue'.
397 #define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
400 if (!ssh->t) ssh->t = snew(struct t); \
402 #define crFinish(z) } *crLine = 0; return (z); }
403 #define crFinishV } *crLine = 0; return; }
404 #define crReturn(z) \
406 *crLine =__LINE__; return (z); case __LINE__:;\
410 *crLine=__LINE__; return; case __LINE__:;\
412 #define crStop(z) do{ *crLine = 0; return (z); }while(0)
413 #define crStopV do{ *crLine = 0; return; }while(0)
414 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
415 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
417 typedef struct ssh_tag
*Ssh
;
420 static struct Packet
*ssh1_pkt_init(int pkt_type
);
421 static struct Packet
*ssh2_pkt_init(int pkt_type
);
422 static void ssh_pkt_ensure(struct Packet
*, int length
);
423 static void ssh_pkt_adddata(struct Packet
*, void *data
, int len
);
424 static void ssh_pkt_addbyte(struct Packet
*, unsigned char value
);
425 static void ssh2_pkt_addbool(struct Packet
*, unsigned char value
);
426 static void ssh_pkt_adduint32(struct Packet
*, unsigned long value
);
427 static void ssh_pkt_addstring_start(struct Packet
*);
428 static void ssh_pkt_addstring_str(struct Packet
*, char *data
);
429 static void ssh_pkt_addstring_data(struct Packet
*, char *data
, int len
);
430 static void ssh_pkt_addstring(struct Packet
*, char *data
);
431 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
);
432 static void ssh1_pkt_addmp(struct Packet
*, Bignum b
);
433 static void ssh2_pkt_addmp(struct Packet
*, Bignum b
);
434 static int ssh2_pkt_construct(Ssh
, struct Packet
*);
435 static void ssh2_pkt_send(Ssh
, struct Packet
*);
436 static void ssh2_pkt_send_noqueue(Ssh
, struct Packet
*);
437 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
438 struct Packet
*pktin
);
439 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
440 struct Packet
*pktin
);
443 * Buffer management constants. There are several of these for
444 * various different purposes:
446 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
447 * on a local data stream before we throttle the whole SSH
448 * connection (in SSH-1 only). Throttling the whole connection is
449 * pretty drastic so we set this high in the hope it won't
452 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
453 * on the SSH connection itself before we defensively throttle
454 * _all_ local data streams. This is pretty drastic too (though
455 * thankfully unlikely in SSH-2 since the window mechanism should
456 * ensure that the server never has any need to throttle its end
457 * of the connection), so we set this high as well.
459 * - OUR_V2_WINSIZE is the maximum window size we present on SSH-2
463 #define SSH1_BUFFER_LIMIT 32768
464 #define SSH_MAX_BACKLOG 32768
465 #define OUR_V2_WINSIZE 16384
466 #define OUR_V2_MAXPKT 0x4000UL
468 /* Maximum length of passwords/passphrases (arbitrary) */
469 #define SSH_MAX_PASSWORD_LEN 100
471 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
473 const static struct ssh_mac
*macs
[] = {
474 &ssh_hmac_sha1
, &ssh_hmac_sha1_96
, &ssh_hmac_md5
476 const static struct ssh_mac
*buggymacs
[] = {
477 &ssh_hmac_sha1_buggy
, &ssh_hmac_sha1_96_buggy
, &ssh_hmac_md5
480 static void *ssh_comp_none_init(void)
484 static void ssh_comp_none_cleanup(void *handle
)
487 static int ssh_comp_none_block(void *handle
, unsigned char *block
, int len
,
488 unsigned char **outblock
, int *outlen
)
492 static int ssh_comp_none_disable(void *handle
)
496 const static struct ssh_compress ssh_comp_none
= {
498 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
499 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
500 ssh_comp_none_disable
, NULL
502 extern const struct ssh_compress ssh_zlib
;
503 const static struct ssh_compress
*compressions
[] = {
504 &ssh_zlib
, &ssh_comp_none
507 enum { /* channel types */
512 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
516 * 2-3-4 tree storing channels.
519 Ssh ssh
; /* pointer back to main context */
520 unsigned remoteid
, localid
;
522 /* True if we opened this channel but server hasn't confirmed. */
525 * In SSH-1, this value contains four bits:
527 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
528 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
529 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
530 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
532 * A channel is completely finished with when all four bits are set.
536 struct ssh1_data_channel
{
539 struct ssh2_data_channel
{
541 unsigned remwindow
, remmaxpkt
;
546 struct ssh_agent_channel
{
547 unsigned char *message
;
548 unsigned char msglen
[4];
549 unsigned lensofar
, totallen
;
551 struct ssh_x11_channel
{
554 struct ssh_pfd_channel
{
561 * 2-3-4 tree storing remote->local port forwardings. SSH-1 and SSH-2
562 * use this structure in different ways, reflecting SSH-2's
563 * altogether saner approach to port forwarding.
565 * In SSH-1, you arrange a remote forwarding by sending the server
566 * the remote port number, and the local destination host:port.
567 * When a connection comes in, the server sends you back that
568 * host:port pair, and you connect to it. This is a ready-made
569 * security hole if you're not on the ball: a malicious server
570 * could send you back _any_ host:port pair, so if you trustingly
571 * connect to the address it gives you then you've just opened the
572 * entire inside of your corporate network just by connecting
573 * through it to a dodgy SSH server. Hence, we must store a list of
574 * host:port pairs we _are_ trying to forward to, and reject a
575 * connection request from the server if it's not in the list.
577 * In SSH-2, each side of the connection minds its own business and
578 * doesn't send unnecessary information to the other. You arrange a
579 * remote forwarding by sending the server just the remote port
580 * number. When a connection comes in, the server tells you which
581 * of its ports was connected to; and _you_ have to remember what
582 * local host:port pair went with that port number.
584 * Hence, in SSH-1 this structure is indexed by destination
585 * host:port pair, whereas in SSH-2 it is indexed by source port.
587 struct ssh_portfwd
; /* forward declaration */
589 struct ssh_rportfwd
{
590 unsigned sport
, dport
;
593 struct ssh_portfwd
*pfrec
;
595 #define free_rportfwd(pf) ( \
596 ((pf) ? (sfree((pf)->sportdesc)) : (void)0 ), sfree(pf) )
599 * Separately to the rportfwd tree (which is for looking up port
600 * open requests from the server), a tree of _these_ structures is
601 * used to keep track of all the currently open port forwardings,
602 * so that we can reconfigure in mid-session if the user requests
606 enum { DESTROY
, KEEP
, CREATE
} status
;
608 unsigned sport
, dport
;
611 struct ssh_rportfwd
*remote
;
615 #define free_portfwd(pf) ( \
616 ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr), \
617 sfree((pf)->sserv), sfree((pf)->dserv)) : (void)0 ), sfree(pf) )
620 long length
; /* length of `data' actually used */
621 long forcepad
; /* SSH-2: force padding to at least this length */
622 int type
; /* only used for incoming packets */
623 unsigned long sequence
; /* SSH-2 incoming sequence number */
624 unsigned char *data
; /* allocated storage */
625 unsigned char *body
; /* offset of payload within `data' */
626 long savedpos
; /* temporary index into `data' (for strings) */
627 long maxlen
; /* amount of storage allocated for `data' */
628 long encrypted_len
; /* for SSH-2 total-size counting */
631 * State associated with packet logging
635 struct logblank_t
*blanks
;
638 static void ssh1_protocol(Ssh ssh
, void *vin
, int inlen
,
639 struct Packet
*pktin
);
640 static void ssh2_protocol(Ssh ssh
, void *vin
, int inlen
,
641 struct Packet
*pktin
);
642 static void ssh1_protocol_setup(Ssh ssh
);
643 static void ssh2_protocol_setup(Ssh ssh
);
644 static void ssh_size(void *handle
, int width
, int height
);
645 static void ssh_special(void *handle
, Telnet_Special
);
646 static int ssh2_try_send(struct ssh_channel
*c
);
647 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
648 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
649 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
650 static int ssh_sendbuffer(void *handle
);
651 static int ssh_do_close(Ssh ssh
, int notify_exit
);
652 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
);
653 static int ssh2_pkt_getbool(struct Packet
*pkt
);
654 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
);
655 static void ssh2_timer(void *ctx
, long now
);
656 static int do_ssh2_transport(Ssh ssh
, void *vin
, int inlen
,
657 struct Packet
*pktin
);
659 struct rdpkt1_state_tag
{
660 long len
, pad
, biglen
, to_read
;
661 unsigned long realcrc
, gotcrc
;
665 struct Packet
*pktin
;
668 struct rdpkt2_state_tag
{
669 long len
, pad
, payload
, packetlen
, maclen
;
672 unsigned long incoming_sequence
;
673 struct Packet
*pktin
;
676 typedef void (*handler_fn_t
)(Ssh ssh
, struct Packet
*pktin
);
677 typedef void (*chandler_fn_t
)(Ssh ssh
, struct Packet
*pktin
, void *ctx
);
679 struct queued_handler
;
680 struct queued_handler
{
682 chandler_fn_t handler
;
684 struct queued_handler
*next
;
688 const struct plug_function_table
*fn
;
689 /* the above field _must_ be first in the structure */
699 unsigned char session_key
[32];
701 int v1_remote_protoflags
;
702 int v1_local_protoflags
;
703 int agentfwd_enabled
;
706 const struct ssh_cipher
*cipher
;
709 const struct ssh2_cipher
*cscipher
, *sccipher
;
710 void *cs_cipher_ctx
, *sc_cipher_ctx
;
711 const struct ssh_mac
*csmac
, *scmac
;
712 void *cs_mac_ctx
, *sc_mac_ctx
;
713 const struct ssh_compress
*cscomp
, *sccomp
;
714 void *cs_comp_ctx
, *sc_comp_ctx
;
715 const struct ssh_kex
*kex
;
716 const struct ssh_signkey
*hostkey
;
717 unsigned char v2_session_id
[SSH2_KEX_MAX_HASH_LEN
];
718 int v2_session_id_len
;
724 int echoing
, editing
;
728 int ospeed
, ispeed
; /* temporaries */
729 int term_width
, term_height
;
731 tree234
*channels
; /* indexed by local id */
732 struct ssh_channel
*mainchan
; /* primary session channel */
733 int ncmode
; /* is primary channel direct-tcpip? */
738 tree234
*rportfwds
, *portfwds
;
742 SSH_STATE_BEFORE_SIZE
,
748 int size_needed
, eof_needed
;
750 struct Packet
**queue
;
751 int queuelen
, queuesize
;
753 unsigned char *deferred_send_data
;
754 int deferred_len
, deferred_size
;
757 * Gross hack: pscp will try to start SFTP but fall back to
758 * scp1 if that fails. This variable is the means by which
759 * scp.c can reach into the SSH code and find out which one it
764 bufchain banner
; /* accumulates banners during do_ssh2_authconn */
771 int v1_throttle_count
;
774 int v1_stdout_throttling
;
775 unsigned long v2_outgoing_sequence
;
777 int ssh1_rdpkt_crstate
;
778 int ssh2_rdpkt_crstate
;
779 int do_ssh_init_crstate
;
780 int ssh_gotdata_crstate
;
781 int do_ssh1_login_crstate
;
782 int do_ssh1_connection_crstate
;
783 int do_ssh2_transport_crstate
;
784 int do_ssh2_authconn_crstate
;
786 void *do_ssh_init_state
;
787 void *do_ssh1_login_state
;
788 void *do_ssh2_transport_state
;
789 void *do_ssh2_authconn_state
;
791 struct rdpkt1_state_tag rdpkt1_state
;
792 struct rdpkt2_state_tag rdpkt2_state
;
794 /* SSH-1 and SSH-2 use this for different things, but both use it */
795 int protocol_initial_phase_done
;
797 void (*protocol
) (Ssh ssh
, void *vin
, int inlen
,
799 struct Packet
*(*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
802 * We maintain a full _copy_ of a Config structure here, not
803 * merely a pointer to it. That way, when we're passed a new
804 * one for reconfiguration, we can check the differences and
805 * potentially reconfigure port forwardings etc in mid-session.
810 * Used to transfer data back from async callbacks.
812 void *agent_response
;
813 int agent_response_len
;
817 * The SSH connection can be set as `frozen', meaning we are
818 * not currently accepting incoming data from the network. This
819 * is slightly more serious than setting the _socket_ as
820 * frozen, because we may already have had data passed to us
821 * from the network which we need to delay processing until
822 * after the freeze is lifted, so we also need a bufchain to
826 bufchain queued_incoming_data
;
829 * Dispatch table for packet types that we may have to deal
832 handler_fn_t packet_dispatch
[256];
835 * Queues of one-off handler functions for success/failure
836 * indications from a request.
838 struct queued_handler
*qhead
, *qtail
;
841 * This module deals with sending keepalives.
846 * Track incoming and outgoing data sizes and time, for
849 unsigned long incoming_data_size
, outgoing_data_size
, deferred_data_size
;
850 unsigned long max_data_size
;
852 long next_rekey
, last_rekey
;
853 char *deferred_rekey_reason
; /* points to STATIC string; don't free */
856 #define logevent(s) logevent(ssh->frontend, s)
858 /* logevent, only printf-formatted. */
859 static void logeventf(Ssh ssh
, const char *fmt
, ...)
865 buf
= dupvprintf(fmt
, ap
);
871 #define bombout(msg) \
873 char *text = dupprintf msg; \
874 ssh_do_close(ssh, FALSE); \
876 connection_fatal(ssh->frontend, "%s", text); \
880 /* Functions to leave bits out of the SSH packet log file. */
882 static void dont_log_password(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
884 if (ssh
->cfg
.logomitpass
)
885 pkt
->logmode
= blanktype
;
888 static void dont_log_data(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
890 if (ssh
->cfg
.logomitdata
)
891 pkt
->logmode
= blanktype
;
894 static void end_log_omission(Ssh ssh
, struct Packet
*pkt
)
896 pkt
->logmode
= PKTLOG_EMIT
;
899 /* Helper function for common bits of parsing cfg.ttymodes. */
900 static void parse_ttymodes(Ssh ssh
, char *modes
,
901 void (*do_mode
)(void *data
, char *mode
, char *val
),
905 char *t
= strchr(modes
, '\t');
906 char *m
= snewn(t
-modes
+1, char);
908 strncpy(m
, modes
, t
-modes
);
911 val
= get_ttymode(ssh
->frontend
, m
);
915 do_mode(data
, m
, val
);
918 modes
+= strlen(modes
) + 1;
922 static int ssh_channelcmp(void *av
, void *bv
)
924 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
925 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
926 if (a
->localid
< b
->localid
)
928 if (a
->localid
> b
->localid
)
932 static int ssh_channelfind(void *av
, void *bv
)
934 unsigned *a
= (unsigned *) av
;
935 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
943 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
945 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
946 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
948 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
949 return i
< 0 ?
-1 : +1;
950 if (a
->dport
> b
->dport
)
952 if (a
->dport
< b
->dport
)
957 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
959 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
960 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
962 if (a
->sport
> b
->sport
)
964 if (a
->sport
< b
->sport
)
970 * Special form of strcmp which can cope with NULL inputs. NULL is
971 * defined to sort before even the empty string.
973 static int nullstrcmp(const char *a
, const char *b
)
975 if (a
== NULL
&& b
== NULL
)
984 static int ssh_portcmp(void *av
, void *bv
)
986 struct ssh_portfwd
*a
= (struct ssh_portfwd
*) av
;
987 struct ssh_portfwd
*b
= (struct ssh_portfwd
*) bv
;
989 if (a
->type
> b
->type
)
991 if (a
->type
< b
->type
)
993 if (a
->addressfamily
> b
->addressfamily
)
995 if (a
->addressfamily
< b
->addressfamily
)
997 if ( (i
= nullstrcmp(a
->saddr
, b
->saddr
)) != 0)
998 return i
< 0 ?
-1 : +1;
999 if (a
->sport
> b
->sport
)
1001 if (a
->sport
< b
->sport
)
1003 if (a
->type
!= 'D') {
1004 if ( (i
= nullstrcmp(a
->daddr
, b
->daddr
)) != 0)
1005 return i
< 0 ?
-1 : +1;
1006 if (a
->dport
> b
->dport
)
1008 if (a
->dport
< b
->dport
)
1014 static int alloc_channel_id(Ssh ssh
)
1016 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
1017 unsigned low
, high
, mid
;
1019 struct ssh_channel
*c
;
1022 * First-fit allocation of channel numbers: always pick the
1023 * lowest unused one. To do this, binary-search using the
1024 * counted B-tree to find the largest channel ID which is in a
1025 * contiguous sequence from the beginning. (Precisely
1026 * everything in that sequence must have ID equal to its tree
1027 * index plus CHANNEL_NUMBER_OFFSET.)
1029 tsize
= count234(ssh
->channels
);
1033 while (high
- low
> 1) {
1034 mid
= (high
+ low
) / 2;
1035 c
= index234(ssh
->channels
, mid
);
1036 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
1037 low
= mid
; /* this one is fine */
1039 high
= mid
; /* this one is past it */
1042 * Now low points to either -1, or the tree index of the
1043 * largest ID in the initial sequence.
1046 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
1047 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
1049 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
1052 static void c_write_stderr(int trusted
, const char *buf
, int len
)
1055 for (i
= 0; i
< len
; i
++)
1056 if (buf
[i
] != '\r' && (trusted
|| buf
[i
] == '\n' || (buf
[i
] & 0x60)))
1057 fputc(buf
[i
], stderr
);
1060 static void c_write(Ssh ssh
, const char *buf
, int len
)
1062 if (flags
& FLAG_STDERR
)
1063 c_write_stderr(1, buf
, len
);
1065 from_backend(ssh
->frontend
, 1, buf
, len
);
1068 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
1070 if (flags
& FLAG_STDERR
)
1071 c_write_stderr(0, buf
, len
);
1073 from_backend_untrusted(ssh
->frontend
, buf
, len
);
1076 static void c_write_str(Ssh ssh
, const char *buf
)
1078 c_write(ssh
, buf
, strlen(buf
));
1081 static void ssh_free_packet(struct Packet
*pkt
)
1086 static struct Packet
*ssh_new_packet(void)
1088 struct Packet
*pkt
= snew(struct Packet
);
1090 pkt
->body
= pkt
->data
= NULL
;
1092 pkt
->logmode
= PKTLOG_EMIT
;
1100 * Collect incoming data in the incoming packet buffer.
1101 * Decipher and verify the packet when it is completely read.
1102 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
1103 * Update the *data and *datalen variables.
1104 * Return a Packet structure when a packet is completed.
1106 static struct Packet
*ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1108 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
1110 crBegin(ssh
->ssh1_rdpkt_crstate
);
1112 st
->pktin
= ssh_new_packet();
1114 st
->pktin
->type
= 0;
1115 st
->pktin
->length
= 0;
1117 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
1118 while ((*datalen
) == 0)
1120 st
->len
= (st
->len
<< 8) + **data
;
1121 (*data
)++, (*datalen
)--;
1124 st
->pad
= 8 - (st
->len
% 8);
1125 st
->biglen
= st
->len
+ st
->pad
;
1126 st
->pktin
->length
= st
->len
- 5;
1128 if (st
->biglen
< 0) {
1129 bombout(("Extremely large packet length from server suggests"
1130 " data stream corruption"));
1131 ssh_free_packet(st
->pktin
);
1135 st
->pktin
->maxlen
= st
->biglen
;
1136 st
->pktin
->data
= snewn(st
->biglen
+ APIEXTRA
, unsigned char);
1138 st
->to_read
= st
->biglen
;
1139 st
->p
= st
->pktin
->data
;
1140 while (st
->to_read
> 0) {
1141 st
->chunk
= st
->to_read
;
1142 while ((*datalen
) == 0)
1144 if (st
->chunk
> (*datalen
))
1145 st
->chunk
= (*datalen
);
1146 memcpy(st
->p
, *data
, st
->chunk
);
1148 *datalen
-= st
->chunk
;
1150 st
->to_read
-= st
->chunk
;
1153 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, st
->pktin
->data
,
1154 st
->biglen
, NULL
)) {
1155 bombout(("Network attack (CRC compensation) detected!"));
1156 ssh_free_packet(st
->pktin
);
1161 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, st
->pktin
->data
, st
->biglen
);
1163 st
->realcrc
= crc32_compute(st
->pktin
->data
, st
->biglen
- 4);
1164 st
->gotcrc
= GET_32BIT(st
->pktin
->data
+ st
->biglen
- 4);
1165 if (st
->gotcrc
!= st
->realcrc
) {
1166 bombout(("Incorrect CRC received on packet"));
1167 ssh_free_packet(st
->pktin
);
1171 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1172 st
->pktin
->savedpos
= 0;
1174 if (ssh
->v1_compressing
) {
1175 unsigned char *decompblk
;
1177 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
1178 st
->pktin
->body
- 1, st
->pktin
->length
+ 1,
1179 &decompblk
, &decomplen
)) {
1180 bombout(("Zlib decompression encountered invalid data"));
1181 ssh_free_packet(st
->pktin
);
1185 if (st
->pktin
->maxlen
< st
->pad
+ decomplen
) {
1186 st
->pktin
->maxlen
= st
->pad
+ decomplen
;
1187 st
->pktin
->data
= sresize(st
->pktin
->data
,
1188 st
->pktin
->maxlen
+ APIEXTRA
,
1190 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1193 memcpy(st
->pktin
->body
- 1, decompblk
, decomplen
);
1195 st
->pktin
->length
= decomplen
- 1;
1198 st
->pktin
->type
= st
->pktin
->body
[-1];
1201 * Log incoming packet, possibly omitting sensitive fields.
1205 struct logblank_t blank
;
1206 if (ssh
->cfg
.logomitdata
) {
1207 int do_blank
= FALSE
, blank_prefix
= 0;
1208 /* "Session data" packets - omit the data field */
1209 if ((st
->pktin
->type
== SSH1_SMSG_STDOUT_DATA
) ||
1210 (st
->pktin
->type
== SSH1_SMSG_STDERR_DATA
)) {
1211 do_blank
= TRUE
; blank_prefix
= 0;
1212 } else if (st
->pktin
->type
== SSH1_MSG_CHANNEL_DATA
) {
1213 do_blank
= TRUE
; blank_prefix
= 4;
1216 blank
.offset
= blank_prefix
;
1217 blank
.len
= st
->pktin
->length
;
1218 blank
.type
= PKTLOG_OMIT
;
1222 log_packet(ssh
->logctx
,
1223 PKT_INCOMING
, st
->pktin
->type
,
1224 ssh1_pkt_type(st
->pktin
->type
),
1225 st
->pktin
->body
, st
->pktin
->length
,
1229 crFinish(st
->pktin
);
1232 static struct Packet
*ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1234 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1236 crBegin(ssh
->ssh2_rdpkt_crstate
);
1238 st
->pktin
= ssh_new_packet();
1240 st
->pktin
->type
= 0;
1241 st
->pktin
->length
= 0;
1243 st
->cipherblk
= ssh
->sccipher
->blksize
;
1246 if (st
->cipherblk
< 8)
1249 st
->pktin
->data
= snewn(st
->cipherblk
+ APIEXTRA
, unsigned char);
1252 * Acquire and decrypt the first block of the packet. This will
1253 * contain the length and padding details.
1255 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1256 while ((*datalen
) == 0)
1258 st
->pktin
->data
[st
->i
] = *(*data
)++;
1263 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1264 st
->pktin
->data
, st
->cipherblk
);
1267 * Now get the length and padding figures.
1269 st
->len
= GET_32BIT(st
->pktin
->data
);
1270 st
->pad
= st
->pktin
->data
[4];
1273 * _Completely_ silly lengths should be stomped on before they
1274 * do us any more damage.
1276 if (st
->len
< 0 || st
->len
> 35000 || st
->pad
< 4 ||
1277 st
->len
- st
->pad
< 1 || (st
->len
+ 4) % st
->cipherblk
!= 0) {
1278 bombout(("Incoming packet was garbled on decryption"));
1279 ssh_free_packet(st
->pktin
);
1284 * This enables us to deduce the payload length.
1286 st
->payload
= st
->len
- st
->pad
- 1;
1288 st
->pktin
->length
= st
->payload
+ 5;
1291 * So now we can work out the total packet length.
1293 st
->packetlen
= st
->len
+ 4;
1294 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1297 * Allocate memory for the rest of the packet.
1299 st
->pktin
->maxlen
= st
->packetlen
+ st
->maclen
;
1300 st
->pktin
->data
= sresize(st
->pktin
->data
,
1301 st
->pktin
->maxlen
+ APIEXTRA
,
1305 * Read and decrypt the remainder of the packet.
1307 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1309 while ((*datalen
) == 0)
1311 st
->pktin
->data
[st
->i
] = *(*data
)++;
1314 /* Decrypt everything _except_ the MAC. */
1316 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1317 st
->pktin
->data
+ st
->cipherblk
,
1318 st
->packetlen
- st
->cipherblk
);
1320 st
->pktin
->encrypted_len
= st
->packetlen
;
1326 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, st
->pktin
->data
, st
->len
+ 4,
1327 st
->incoming_sequence
)) {
1328 bombout(("Incorrect MAC received on packet"));
1329 ssh_free_packet(st
->pktin
);
1333 st
->pktin
->sequence
= st
->incoming_sequence
++;
1336 * Decompress packet payload.
1339 unsigned char *newpayload
;
1342 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1343 st
->pktin
->data
+ 5, st
->pktin
->length
- 5,
1344 &newpayload
, &newlen
)) {
1345 if (st
->pktin
->maxlen
< newlen
+ 5) {
1346 st
->pktin
->maxlen
= newlen
+ 5;
1347 st
->pktin
->data
= sresize(st
->pktin
->data
,
1348 st
->pktin
->maxlen
+ APIEXTRA
,
1351 st
->pktin
->length
= 5 + newlen
;
1352 memcpy(st
->pktin
->data
+ 5, newpayload
, newlen
);
1357 st
->pktin
->savedpos
= 6;
1358 st
->pktin
->body
= st
->pktin
->data
;
1359 st
->pktin
->type
= st
->pktin
->data
[5];
1362 * Log incoming packet, possibly omitting sensitive fields.
1366 struct logblank_t blank
;
1367 if (ssh
->cfg
.logomitdata
) {
1368 int do_blank
= FALSE
, blank_prefix
= 0;
1369 /* "Session data" packets - omit the data field */
1370 if (st
->pktin
->type
== SSH2_MSG_CHANNEL_DATA
) {
1371 do_blank
= TRUE
; blank_prefix
= 4;
1372 } else if (st
->pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1373 do_blank
= TRUE
; blank_prefix
= 8;
1376 blank
.offset
= blank_prefix
;
1377 blank
.len
= (st
->pktin
->length
-6) - blank_prefix
;
1378 blank
.type
= PKTLOG_OMIT
;
1382 log_packet(ssh
->logctx
, PKT_INCOMING
, st
->pktin
->type
,
1383 ssh2_pkt_type(ssh
->pkt_ctx
, st
->pktin
->type
),
1384 st
->pktin
->data
+6, st
->pktin
->length
-6,
1388 crFinish(st
->pktin
);
1391 static int s_wrpkt_prepare(Ssh ssh
, struct Packet
*pkt
, int *offset_p
)
1393 int pad
, biglen
, i
, pktoffs
;
1397 * XXX various versions of SC (including 8.8.4) screw up the
1398 * register allocation in this function and use the same register
1399 * (D6) for len and as a temporary, with predictable results. The
1400 * following sledgehammer prevents this.
1407 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[12],
1408 ssh1_pkt_type(pkt
->data
[12]),
1409 pkt
->body
, pkt
->length
- (pkt
->body
- pkt
->data
),
1410 pkt
->nblanks
, pkt
->blanks
);
1411 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1414 if (ssh
->v1_compressing
) {
1415 unsigned char *compblk
;
1417 zlib_compress_block(ssh
->cs_comp_ctx
,
1418 pkt
->data
+ 12, pkt
->length
- 12,
1419 &compblk
, &complen
);
1420 memcpy(pkt
->data
+ 12, compblk
, complen
);
1422 pkt
->length
= complen
+ 12;
1425 ssh_pkt_ensure(pkt
, pkt
->length
+ 4); /* space for CRC */
1427 len
= pkt
->length
- 4 - 8; /* len(type+data+CRC) */
1428 pad
= 8 - (len
% 8);
1430 biglen
= len
+ pad
; /* len(padding+type+data+CRC) */
1432 for (i
= pktoffs
; i
< 4+8; i
++)
1433 pkt
->data
[i
] = random_byte();
1434 crc
= crc32_compute(pkt
->data
+ pktoffs
+ 4, biglen
- 4); /* all ex len */
1435 PUT_32BIT(pkt
->data
+ pktoffs
+ 4 + biglen
- 4, crc
);
1436 PUT_32BIT(pkt
->data
+ pktoffs
, len
);
1439 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
,
1440 pkt
->data
+ pktoffs
+ 4, biglen
);
1442 if (offset_p
) *offset_p
= pktoffs
;
1443 return biglen
+ 4; /* len(length+padding+type+data+CRC) */
1446 static int s_write(Ssh ssh
, void *data
, int len
)
1448 log_packet(ssh
->logctx
, PKT_OUTGOING
, -1, NULL
, data
, len
, 0, NULL
);
1449 return sk_write(ssh
->s
, (char *)data
, len
);
1452 static void s_wrpkt(Ssh ssh
, struct Packet
*pkt
)
1454 int len
, backlog
, offset
;
1455 len
= s_wrpkt_prepare(ssh
, pkt
, &offset
);
1456 backlog
= s_write(ssh
, pkt
->data
+ offset
, len
);
1457 if (backlog
> SSH_MAX_BACKLOG
)
1458 ssh_throttle_all(ssh
, 1, backlog
);
1459 ssh_free_packet(pkt
);
1462 static void s_wrpkt_defer(Ssh ssh
, struct Packet
*pkt
)
1465 len
= s_wrpkt_prepare(ssh
, pkt
, &offset
);
1466 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1467 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1468 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1472 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
,
1473 pkt
->data
+ offset
, len
);
1474 ssh
->deferred_len
+= len
;
1475 ssh_free_packet(pkt
);
1479 * Construct a SSH-1 packet with the specified contents.
1480 * (This all-at-once interface used to be the only one, but now SSH-1
1481 * packets can also be constructed incrementally.)
1483 static struct Packet
*construct_packet(Ssh ssh
, int pkttype
, va_list ap
)
1489 pkt
= ssh1_pkt_init(pkttype
);
1491 while ((argtype
= va_arg(ap
, int)) != PKT_END
) {
1492 unsigned char *argp
, argchar
;
1494 unsigned long argint
;
1497 /* Actual fields in the packet */
1499 argint
= va_arg(ap
, int);
1500 ssh_pkt_adduint32(pkt
, argint
);
1503 argchar
= (unsigned char) va_arg(ap
, int);
1504 ssh_pkt_addbyte(pkt
, argchar
);
1507 argp
= va_arg(ap
, unsigned char *);
1508 arglen
= va_arg(ap
, int);
1509 ssh_pkt_adddata(pkt
, argp
, arglen
);
1512 sargp
= va_arg(ap
, char *);
1513 ssh_pkt_addstring(pkt
, sargp
);
1516 bn
= va_arg(ap
, Bignum
);
1517 ssh1_pkt_addmp(pkt
, bn
);
1519 /* Tokens for modifications to packet logging */
1521 dont_log_password(ssh
, pkt
, PKTLOG_BLANK
);
1524 dont_log_data(ssh
, pkt
, PKTLOG_OMIT
);
1527 end_log_omission(ssh
, pkt
);
1535 static void send_packet(Ssh ssh
, int pkttype
, ...)
1539 va_start(ap
, pkttype
);
1540 pkt
= construct_packet(ssh
, pkttype
, ap
);
1545 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1549 va_start(ap
, pkttype
);
1550 pkt
= construct_packet(ssh
, pkttype
, ap
);
1552 s_wrpkt_defer(ssh
, pkt
);
1555 static int ssh_versioncmp(char *a
, char *b
)
1558 unsigned long av
, bv
;
1560 av
= strtoul(a
, &ae
, 10);
1561 bv
= strtoul(b
, &be
, 10);
1563 return (av
< bv ?
-1 : +1);
1568 av
= strtoul(ae
, &ae
, 10);
1569 bv
= strtoul(be
, &be
, 10);
1571 return (av
< bv ?
-1 : +1);
1576 * Utility routines for putting an SSH-protocol `string' and
1577 * `uint32' into a hash state.
1579 static void hash_string(const struct ssh_hash
*h
, void *s
, void *str
, int len
)
1581 unsigned char lenblk
[4];
1582 PUT_32BIT(lenblk
, len
);
1583 h
->bytes(s
, lenblk
, 4);
1584 h
->bytes(s
, str
, len
);
1587 static void hash_uint32(const struct ssh_hash
*h
, void *s
, unsigned i
)
1589 unsigned char intblk
[4];
1590 PUT_32BIT(intblk
, i
);
1591 h
->bytes(s
, intblk
, 4);
1595 * Packet construction functions. Mostly shared between SSH-1 and SSH-2.
1597 static void ssh_pkt_ensure(struct Packet
*pkt
, int length
)
1599 if (pkt
->maxlen
< length
) {
1600 unsigned char *body
= pkt
->body
;
1601 int offset
= body ? body
- pkt
->data
: 0;
1602 pkt
->maxlen
= length
+ 256;
1603 pkt
->data
= sresize(pkt
->data
, pkt
->maxlen
+ APIEXTRA
, unsigned char);
1604 if (body
) pkt
->body
= pkt
->data
+ offset
;
1607 static void ssh_pkt_adddata(struct Packet
*pkt
, void *data
, int len
)
1609 if (pkt
->logmode
!= PKTLOG_EMIT
) {
1611 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
, struct logblank_t
);
1613 pkt
->blanks
[pkt
->nblanks
-1].offset
= pkt
->length
-
1614 (pkt
->body
- pkt
->data
);
1615 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1616 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1619 ssh_pkt_ensure(pkt
, pkt
->length
);
1620 memcpy(pkt
->data
+ pkt
->length
- len
, data
, len
);
1622 static void ssh_pkt_addbyte(struct Packet
*pkt
, unsigned char byte
)
1624 ssh_pkt_adddata(pkt
, &byte
, 1);
1626 static void ssh2_pkt_addbool(struct Packet
*pkt
, unsigned char value
)
1628 ssh_pkt_adddata(pkt
, &value
, 1);
1630 static void ssh_pkt_adduint32(struct Packet
*pkt
, unsigned long value
)
1633 PUT_32BIT(x
, value
);
1634 ssh_pkt_adddata(pkt
, x
, 4);
1636 static void ssh_pkt_addstring_start(struct Packet
*pkt
)
1638 ssh_pkt_adduint32(pkt
, 0);
1639 pkt
->savedpos
= pkt
->length
;
1641 static void ssh_pkt_addstring_str(struct Packet
*pkt
, char *data
)
1643 ssh_pkt_adddata(pkt
, data
, strlen(data
));
1644 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1646 static void ssh_pkt_addstring_data(struct Packet
*pkt
, char *data
, int len
)
1648 ssh_pkt_adddata(pkt
, data
, len
);
1649 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1651 static void ssh_pkt_addstring(struct Packet
*pkt
, char *data
)
1653 ssh_pkt_addstring_start(pkt
);
1654 ssh_pkt_addstring_str(pkt
, data
);
1656 static void ssh1_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1658 int len
= ssh1_bignum_length(b
);
1659 unsigned char *data
= snewn(len
, unsigned char);
1660 (void) ssh1_write_bignum(data
, b
);
1661 ssh_pkt_adddata(pkt
, data
, len
);
1664 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1667 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1668 p
= snewn(n
+ 1, unsigned char);
1670 for (i
= 1; i
<= n
; i
++)
1671 p
[i
] = bignum_byte(b
, n
- i
);
1673 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1675 memmove(p
, p
+ i
, n
+ 1 - i
);
1679 static void ssh2_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1683 p
= ssh2_mpint_fmt(b
, &len
);
1684 ssh_pkt_addstring_start(pkt
);
1685 ssh_pkt_addstring_data(pkt
, (char *)p
, len
);
1689 static struct Packet
*ssh1_pkt_init(int pkt_type
)
1691 struct Packet
*pkt
= ssh_new_packet();
1692 pkt
->length
= 4 + 8; /* space for length + max padding */
1693 ssh_pkt_addbyte(pkt
, pkt_type
);
1694 pkt
->body
= pkt
->data
+ pkt
->length
;
1698 /* For legacy code (SSH-1 and -2 packet construction used to be separate) */
1699 #define ssh2_pkt_ensure(pkt, length) ssh_pkt_ensure(pkt, length)
1700 #define ssh2_pkt_adddata(pkt, data, len) ssh_pkt_adddata(pkt, data, len)
1701 #define ssh2_pkt_addbyte(pkt, byte) ssh_pkt_addbyte(pkt, byte)
1702 #define ssh2_pkt_adduint32(pkt, value) ssh_pkt_adduint32(pkt, value)
1703 #define ssh2_pkt_addstring_start(pkt) ssh_pkt_addstring_start(pkt)
1704 #define ssh2_pkt_addstring_str(pkt, data) ssh_pkt_addstring_str(pkt, data)
1705 #define ssh2_pkt_addstring_data(pkt, data, len) ssh_pkt_addstring_data(pkt, data, len)
1706 #define ssh2_pkt_addstring(pkt, data) ssh_pkt_addstring(pkt, data)
1708 static struct Packet
*ssh2_pkt_init(int pkt_type
)
1710 struct Packet
*pkt
= ssh_new_packet();
1711 pkt
->length
= 5; /* space for packet length + padding length */
1713 ssh_pkt_addbyte(pkt
, (unsigned char) pkt_type
);
1714 pkt
->body
= pkt
->data
+ pkt
->length
; /* after packet type */
1719 * Construct an SSH-2 final-form packet: compress it, encrypt it,
1720 * put the MAC on it. Final packet, ready to be sent, is stored in
1721 * pkt->data. Total length is returned.
1723 static int ssh2_pkt_construct(Ssh ssh
, struct Packet
*pkt
)
1725 int cipherblk
, maclen
, padding
, i
;
1728 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[5],
1729 ssh2_pkt_type(ssh
->pkt_ctx
, pkt
->data
[5]),
1730 pkt
->body
, pkt
->length
- (pkt
->body
- pkt
->data
),
1731 pkt
->nblanks
, pkt
->blanks
);
1732 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1736 * Compress packet payload.
1739 unsigned char *newpayload
;
1742 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, pkt
->data
+ 5,
1744 &newpayload
, &newlen
)) {
1746 ssh2_pkt_adddata(pkt
, newpayload
, newlen
);
1752 * Add padding. At least four bytes, and must also bring total
1753 * length (minus MAC) up to a multiple of the block size.
1754 * If pkt->forcepad is set, make sure the packet is at least that size
1757 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1758 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1760 if (pkt
->length
+ padding
< pkt
->forcepad
)
1761 padding
= pkt
->forcepad
- pkt
->length
;
1763 (cipherblk
- (pkt
->length
+ padding
) % cipherblk
) % cipherblk
;
1764 assert(padding
<= 255);
1765 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1766 ssh2_pkt_ensure(pkt
, pkt
->length
+ padding
+ maclen
);
1767 pkt
->data
[4] = padding
;
1768 for (i
= 0; i
< padding
; i
++)
1769 pkt
->data
[pkt
->length
+ i
] = random_byte();
1770 PUT_32BIT(pkt
->data
, pkt
->length
+ padding
- 4);
1772 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, pkt
->data
,
1773 pkt
->length
+ padding
,
1774 ssh
->v2_outgoing_sequence
);
1775 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1778 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1779 pkt
->data
, pkt
->length
+ padding
);
1781 pkt
->encrypted_len
= pkt
->length
+ padding
;
1783 /* Ready-to-send packet starts at pkt->data. We return length. */
1784 return pkt
->length
+ padding
+ maclen
;
1788 * Routines called from the main SSH code to send packets. There
1789 * are quite a few of these, because we have two separate
1790 * mechanisms for delaying the sending of packets:
1792 * - In order to send an IGNORE message and a password message in
1793 * a single fixed-length blob, we require the ability to
1794 * concatenate the encrypted forms of those two packets _into_ a
1795 * single blob and then pass it to our <network.h> transport
1796 * layer in one go. Hence, there's a deferment mechanism which
1797 * works after packet encryption.
1799 * - In order to avoid sending any connection-layer messages
1800 * during repeat key exchange, we have to queue up any such
1801 * outgoing messages _before_ they are encrypted (and in
1802 * particular before they're allocated sequence numbers), and
1803 * then send them once we've finished.
1805 * I call these mechanisms `defer' and `queue' respectively, so as
1806 * to distinguish them reasonably easily.
1808 * The functions send_noqueue() and defer_noqueue() free the packet
1809 * structure they are passed. Every outgoing packet goes through
1810 * precisely one of these functions in its life; packets passed to
1811 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1812 * these or get queued, and then when the queue is later emptied
1813 * the packets are all passed to defer_noqueue().
1815 * When using a CBC-mode cipher, it's necessary to ensure that an
1816 * attacker can't provide data to be encrypted using an IV that they
1817 * know. We ensure this by prefixing each packet that might contain
1818 * user data with an SSH_MSG_IGNORE. This is done using the deferral
1819 * mechanism, so in this case send_noqueue() ends up redirecting to
1820 * defer_noqueue(). If you don't like this inefficiency, don't use
1824 static void ssh2_pkt_defer_noqueue(Ssh
, struct Packet
*, int);
1825 static void ssh_pkt_defersend(Ssh
);
1828 * Send an SSH-2 packet immediately, without queuing or deferring.
1830 static void ssh2_pkt_send_noqueue(Ssh ssh
, struct Packet
*pkt
)
1834 if (ssh
->cscipher
!= NULL
&& (ssh
->cscipher
->flags
& SSH_CIPHER_IS_CBC
)) {
1835 /* We need to send two packets, so use the deferral mechanism. */
1836 ssh2_pkt_defer_noqueue(ssh
, pkt
, FALSE
);
1837 ssh_pkt_defersend(ssh
);
1840 len
= ssh2_pkt_construct(ssh
, pkt
);
1841 backlog
= s_write(ssh
, pkt
->data
, len
);
1842 if (backlog
> SSH_MAX_BACKLOG
)
1843 ssh_throttle_all(ssh
, 1, backlog
);
1845 ssh
->outgoing_data_size
+= pkt
->encrypted_len
;
1846 if (!ssh
->kex_in_progress
&&
1847 ssh
->max_data_size
!= 0 &&
1848 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1849 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1851 ssh_free_packet(pkt
);
1855 * Defer an SSH-2 packet.
1857 static void ssh2_pkt_defer_noqueue(Ssh ssh
, struct Packet
*pkt
, int noignore
)
1860 if (ssh
->cscipher
!= NULL
&& (ssh
->cscipher
->flags
& SSH_CIPHER_IS_CBC
) &&
1861 ssh
->deferred_len
== 0 && !noignore
) {
1863 * Interpose an SSH_MSG_IGNORE to ensure that user data don't
1864 * get encrypted with a known IV.
1866 struct Packet
*ipkt
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
1867 ssh2_pkt_addstring_start(ipkt
);
1868 ssh2_pkt_defer_noqueue(ssh
, ipkt
, TRUE
);
1870 len
= ssh2_pkt_construct(ssh
, pkt
);
1871 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1872 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1873 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1877 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1878 ssh
->deferred_len
+= len
;
1879 ssh
->deferred_data_size
+= pkt
->encrypted_len
;
1880 ssh_free_packet(pkt
);
1884 * Queue an SSH-2 packet.
1886 static void ssh2_pkt_queue(Ssh ssh
, struct Packet
*pkt
)
1888 assert(ssh
->queueing
);
1890 if (ssh
->queuelen
>= ssh
->queuesize
) {
1891 ssh
->queuesize
= ssh
->queuelen
+ 32;
1892 ssh
->queue
= sresize(ssh
->queue
, ssh
->queuesize
, struct Packet
*);
1895 ssh
->queue
[ssh
->queuelen
++] = pkt
;
1899 * Either queue or send a packet, depending on whether queueing is
1902 static void ssh2_pkt_send(Ssh ssh
, struct Packet
*pkt
)
1905 ssh2_pkt_queue(ssh
, pkt
);
1907 ssh2_pkt_send_noqueue(ssh
, pkt
);
1911 * Either queue or defer a packet, depending on whether queueing is
1914 static void ssh2_pkt_defer(Ssh ssh
, struct Packet
*pkt
)
1917 ssh2_pkt_queue(ssh
, pkt
);
1919 ssh2_pkt_defer_noqueue(ssh
, pkt
, FALSE
);
1923 * Send the whole deferred data block constructed by
1924 * ssh2_pkt_defer() or SSH-1's defer_packet().
1926 * The expected use of the defer mechanism is that you call
1927 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1928 * not currently queueing, this simply sets up deferred_send_data
1929 * and then sends it. If we _are_ currently queueing, the calls to
1930 * ssh2_pkt_defer() put the deferred packets on to the queue
1931 * instead, and therefore ssh_pkt_defersend() has no deferred data
1932 * to send. Hence, there's no need to make it conditional on
1935 static void ssh_pkt_defersend(Ssh ssh
)
1938 backlog
= s_write(ssh
, ssh
->deferred_send_data
, ssh
->deferred_len
);
1939 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1940 sfree(ssh
->deferred_send_data
);
1941 ssh
->deferred_send_data
= NULL
;
1942 if (backlog
> SSH_MAX_BACKLOG
)
1943 ssh_throttle_all(ssh
, 1, backlog
);
1945 ssh
->outgoing_data_size
+= ssh
->deferred_data_size
;
1946 if (!ssh
->kex_in_progress
&&
1947 ssh
->max_data_size
!= 0 &&
1948 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1949 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1950 ssh
->deferred_data_size
= 0;
1954 * Send a packet whose length needs to be disguised (typically
1955 * passwords or keyboard-interactive responses).
1957 static void ssh2_pkt_send_with_padding(Ssh ssh
, struct Packet
*pkt
,
1963 * The simplest way to do this is to adjust the
1964 * variable-length padding field in the outgoing packet.
1966 * Currently compiled out, because some Cisco SSH servers
1967 * don't like excessively padded packets (bah, why's it
1970 pkt
->forcepad
= padsize
;
1971 ssh2_pkt_send(ssh
, pkt
);
1976 * If we can't do that, however, an alternative approach is
1977 * to use the pkt_defer mechanism to bundle the packet
1978 * tightly together with an SSH_MSG_IGNORE such that their
1979 * combined length is a constant. So first we construct the
1980 * final form of this packet and defer its sending.
1982 ssh2_pkt_defer(ssh
, pkt
);
1985 * Now construct an SSH_MSG_IGNORE which includes a string
1986 * that's an exact multiple of the cipher block size. (If
1987 * the cipher is NULL so that the block size is
1988 * unavailable, we don't do this trick at all, because we
1989 * gain nothing by it.)
1991 if (ssh
->cscipher
) {
1994 stringlen
= (256 - ssh
->deferred_len
);
1995 stringlen
+= ssh
->cscipher
->blksize
- 1;
1996 stringlen
-= (stringlen
% ssh
->cscipher
->blksize
);
1999 * Temporarily disable actual compression, so we
2000 * can guarantee to get this string exactly the
2001 * length we want it. The compression-disabling
2002 * routine should return an integer indicating how
2003 * many bytes we should adjust our string length
2007 ssh
->cscomp
->disable_compression(ssh
->cs_comp_ctx
);
2009 pkt
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
2010 ssh2_pkt_addstring_start(pkt
);
2011 for (i
= 0; i
< stringlen
; i
++) {
2012 char c
= (char) random_byte();
2013 ssh2_pkt_addstring_data(pkt
, &c
, 1);
2015 ssh2_pkt_defer(ssh
, pkt
);
2017 ssh_pkt_defersend(ssh
);
2022 * Send all queued SSH-2 packets. We send them by means of
2023 * ssh2_pkt_defer_noqueue(), in case they included a pair of
2024 * packets that needed to be lumped together.
2026 static void ssh2_pkt_queuesend(Ssh ssh
)
2030 assert(!ssh
->queueing
);
2032 for (i
= 0; i
< ssh
->queuelen
; i
++)
2033 ssh2_pkt_defer_noqueue(ssh
, ssh
->queue
[i
], FALSE
);
2036 ssh_pkt_defersend(ssh
);
2040 void bndebug(char *string
, Bignum b
)
2044 p
= ssh2_mpint_fmt(b
, &len
);
2045 debug(("%s", string
));
2046 for (i
= 0; i
< len
; i
++)
2047 debug((" %02x", p
[i
]));
2053 static void hash_mpint(const struct ssh_hash
*h
, void *s
, Bignum b
)
2057 p
= ssh2_mpint_fmt(b
, &len
);
2058 hash_string(h
, s
, p
, len
);
2063 * Packet decode functions for both SSH-1 and SSH-2.
2065 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
)
2067 unsigned long value
;
2068 if (pkt
->length
- pkt
->savedpos
< 4)
2069 return 0; /* arrgh, no way to decline (FIXME?) */
2070 value
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
2074 static int ssh2_pkt_getbool(struct Packet
*pkt
)
2076 unsigned long value
;
2077 if (pkt
->length
- pkt
->savedpos
< 1)
2078 return 0; /* arrgh, no way to decline (FIXME?) */
2079 value
= pkt
->body
[pkt
->savedpos
] != 0;
2083 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
)
2088 if (pkt
->length
- pkt
->savedpos
< 4)
2090 len
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
2095 if (pkt
->length
- pkt
->savedpos
< *length
)
2097 *p
= (char *)(pkt
->body
+ pkt
->savedpos
);
2098 pkt
->savedpos
+= *length
;
2100 static void *ssh_pkt_getdata(struct Packet
*pkt
, int length
)
2102 if (pkt
->length
- pkt
->savedpos
< length
)
2104 pkt
->savedpos
+= length
;
2105 return pkt
->body
+ (pkt
->savedpos
- length
);
2107 static int ssh1_pkt_getrsakey(struct Packet
*pkt
, struct RSAKey
*key
,
2108 unsigned char **keystr
)
2112 j
= makekey(pkt
->body
+ pkt
->savedpos
,
2113 pkt
->length
- pkt
->savedpos
,
2120 assert(pkt
->savedpos
< pkt
->length
);
2124 static Bignum
ssh1_pkt_getmp(struct Packet
*pkt
)
2129 j
= ssh1_read_bignum(pkt
->body
+ pkt
->savedpos
,
2130 pkt
->length
- pkt
->savedpos
, &b
);
2138 static Bignum
ssh2_pkt_getmp(struct Packet
*pkt
)
2144 ssh_pkt_getstring(pkt
, &p
, &length
);
2149 b
= bignum_from_bytes((unsigned char *)p
, length
);
2154 * Helper function to add an SSH-2 signature blob to a packet.
2155 * Expects to be shown the public key blob as well as the signature
2156 * blob. Normally works just like ssh2_pkt_addstring, but will
2157 * fiddle with the signature packet if necessary for
2158 * BUG_SSH2_RSA_PADDING.
2160 static void ssh2_add_sigblob(Ssh ssh
, struct Packet
*pkt
,
2161 void *pkblob_v
, int pkblob_len
,
2162 void *sigblob_v
, int sigblob_len
)
2164 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
2165 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
2167 /* dmemdump(pkblob, pkblob_len); */
2168 /* dmemdump(sigblob, sigblob_len); */
2171 * See if this is in fact an ssh-rsa signature and a buggy
2172 * server; otherwise we can just do this the easy way.
2174 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
2175 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
2176 int pos
, len
, siglen
;
2179 * Find the byte length of the modulus.
2182 pos
= 4+7; /* skip over "ssh-rsa" */
2183 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
2184 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
2185 pos
+= 4; /* find modulus itself */
2186 while (len
> 0 && pkblob
[pos
] == 0)
2188 /* debug(("modulus length is %d\n", len)); */
2191 * Now find the signature integer.
2193 pos
= 4+7; /* skip over "ssh-rsa" */
2194 siglen
= GET_32BIT(sigblob
+pos
);
2195 /* debug(("signature length is %d\n", siglen)); */
2197 if (len
!= siglen
) {
2198 unsigned char newlen
[4];
2199 ssh2_pkt_addstring_start(pkt
);
2200 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, pos
);
2201 /* dmemdump(sigblob, pos); */
2202 pos
+= 4; /* point to start of actual sig */
2203 PUT_32BIT(newlen
, len
);
2204 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 4);
2205 /* dmemdump(newlen, 4); */
2207 while (len
-- > siglen
) {
2208 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 1);
2209 /* dmemdump(newlen, 1); */
2211 ssh2_pkt_addstring_data(pkt
, (char *)(sigblob
+pos
), siglen
);
2212 /* dmemdump(sigblob+pos, siglen); */
2216 /* Otherwise fall through and do it the easy way. */
2219 ssh2_pkt_addstring_start(pkt
);
2220 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, sigblob_len
);
2224 * Examine the remote side's version string and compare it against
2225 * a list of known buggy implementations.
2227 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
2229 char *imp
; /* pointer to implementation part */
2231 imp
+= strcspn(imp
, "-");
2233 imp
+= strcspn(imp
, "-");
2236 ssh
->remote_bugs
= 0;
2239 * General notes on server version strings:
2240 * - Not all servers reporting "Cisco-1.25" have all the bugs listed
2241 * here -- in particular, we've heard of one that's perfectly happy
2242 * with SSH1_MSG_IGNOREs -- but this string never seems to change,
2243 * so we can't distinguish them.
2245 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
2246 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
2247 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
2248 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
2249 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
2250 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
2252 * These versions don't support SSH1_MSG_IGNORE, so we have
2253 * to use a different defence against password length
2256 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
2257 logevent("We believe remote version has SSH-1 ignore bug");
2260 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
2261 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
2262 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
2264 * These versions need a plain password sent; they can't
2265 * handle having a null and a random length of data after
2268 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
2269 logevent("We believe remote version needs a plain SSH-1 password");
2272 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
2273 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
2274 (!strcmp(imp
, "Cisco-1.25")))) {
2276 * These versions apparently have no clue whatever about
2277 * RSA authentication and will panic and die if they see
2278 * an AUTH_RSA message.
2280 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
2281 logevent("We believe remote version can't handle SSH-1 RSA authentication");
2284 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
2285 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
2286 !wc_match("* VShell", imp
) &&
2287 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
2288 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
2289 wc_match("2.1 *", imp
)))) {
2291 * These versions have the HMAC bug.
2293 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
2294 logevent("We believe remote version has SSH-2 HMAC bug");
2297 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2298 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2299 !wc_match("* VShell", imp
) &&
2300 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2302 * These versions have the key-derivation bug (failing to
2303 * include the literal shared secret in the hashes that
2304 * generate the keys).
2306 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2307 logevent("We believe remote version has SSH-2 key-derivation bug");
2310 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2311 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2312 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2313 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2315 * These versions have the SSH-2 RSA padding bug.
2317 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2318 logevent("We believe remote version has SSH-2 RSA padding bug");
2321 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2322 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2323 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2325 * These versions have the SSH-2 session-ID bug in
2326 * public-key authentication.
2328 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2329 logevent("We believe remote version has SSH-2 public-key-session-ID bug");
2332 if (ssh
->cfg
.sshbug_rekey2
== FORCE_ON
||
2333 (ssh
->cfg
.sshbug_rekey2
== AUTO
&&
2334 (wc_match("DigiSSH_2.0", imp
) ||
2335 wc_match("OpenSSH_2.[0-4]*", imp
) ||
2336 wc_match("OpenSSH_2.5.[0-3]*", imp
) ||
2337 wc_match("Sun_SSH_1.0", imp
) ||
2338 wc_match("Sun_SSH_1.0.1", imp
) ||
2339 /* All versions <= 1.2.6 (they changed their format in 1.2.7) */
2340 wc_match("WeOnlyDo-*", imp
)))) {
2342 * These versions have the SSH-2 rekey bug.
2344 ssh
->remote_bugs
|= BUG_SSH2_REKEY
;
2345 logevent("We believe remote version has SSH-2 rekey bug");
2350 * The `software version' part of an SSH version string is required
2351 * to contain no spaces or minus signs.
2353 static void ssh_fix_verstring(char *str
)
2355 /* Eat "SSH-<protoversion>-". */
2356 assert(*str
== 'S'); str
++;
2357 assert(*str
== 'S'); str
++;
2358 assert(*str
== 'H'); str
++;
2359 assert(*str
== '-'); str
++;
2360 while (*str
&& *str
!= '-') str
++;
2361 assert(*str
== '-'); str
++;
2363 /* Convert minus signs and spaces in the remaining string into
2366 if (*str
== '-' || *str
== ' ')
2372 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2374 struct do_ssh_init_state
{
2382 crState(do_ssh_init_state
);
2384 crBegin(ssh
->do_ssh_init_crstate
);
2386 /* Search for a line beginning with the string "SSH-" in the input. */
2388 if (c
!= 'S') goto no
;
2390 if (c
!= 'S') goto no
;
2392 if (c
!= 'H') goto no
;
2394 if (c
!= '-') goto no
;
2403 s
->vstring
= snewn(s
->vstrsize
, char);
2404 strcpy(s
->vstring
, "SSH-");
2408 crReturn(1); /* get another char */
2409 if (s
->vslen
>= s
->vstrsize
- 1) {
2411 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2413 s
->vstring
[s
->vslen
++] = c
;
2416 s
->version
[s
->i
] = '\0';
2418 } else if (s
->i
< sizeof(s
->version
) - 1)
2419 s
->version
[s
->i
++] = c
;
2420 } else if (c
== '\012')
2424 ssh
->agentfwd_enabled
= FALSE
;
2425 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2427 s
->vstring
[s
->vslen
] = 0;
2428 s
->vstring
[strcspn(s
->vstring
, "\015\012")] = '\0';/* remove EOL chars */
2429 logeventf(ssh
, "Server version: %s", s
->vstring
);
2430 ssh_detect_bugs(ssh
, s
->vstring
);
2433 * Decide which SSH protocol version to support.
2436 /* Anything strictly below "2.0" means protocol 1 is supported. */
2437 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2438 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2439 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2441 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2442 bombout(("SSH protocol version 1 required by user but not provided by server"));
2445 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2446 bombout(("SSH protocol version 2 required by user but not provided by server"));
2453 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2455 * Construct a v2 version string.
2457 verstring
= dupprintf("SSH-2.0-%s\015\012", sshver
);
2461 * Construct a v1 version string.
2463 verstring
= dupprintf("SSH-%s-%s\012",
2464 (ssh_versioncmp(s
->version
, "1.5") <= 0 ?
2465 s
->version
: "1.5"),
2470 ssh_fix_verstring(verstring
);
2472 if (ssh
->version
== 2) {
2475 * Hash our version string and their version string.
2477 len
= strcspn(verstring
, "\015\012");
2478 ssh
->v_c
= snewn(len
+ 1, char);
2479 memcpy(ssh
->v_c
, verstring
, len
);
2481 len
= strcspn(s
->vstring
, "\015\012");
2482 ssh
->v_s
= snewn(len
+ 1, char);
2483 memcpy(ssh
->v_s
, s
->vstring
, len
);
2487 * Initialise SSH-2 protocol.
2489 ssh
->protocol
= ssh2_protocol
;
2490 ssh2_protocol_setup(ssh
);
2491 ssh
->s_rdpkt
= ssh2_rdpkt
;
2494 * Initialise SSH-1 protocol.
2496 ssh
->protocol
= ssh1_protocol
;
2497 ssh1_protocol_setup(ssh
);
2498 ssh
->s_rdpkt
= ssh1_rdpkt
;
2500 logeventf(ssh
, "We claim version: %.*s",
2501 strcspn(verstring
, "\015\012"), verstring
);
2502 s_write(ssh
, verstring
, strlen(verstring
));
2504 if (ssh
->version
== 2)
2505 do_ssh2_transport(ssh
, NULL
, -1, NULL
);
2508 logeventf(ssh
, "Using SSH protocol version %d", ssh
->version
);
2510 update_specials_menu(ssh
->frontend
);
2511 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2512 ssh
->pinger
= pinger_new(&ssh
->cfg
, &ssh_backend
, ssh
);
2519 static void ssh_process_incoming_data(Ssh ssh
,
2520 unsigned char **data
, int *datalen
)
2522 struct Packet
*pktin
;
2524 pktin
= ssh
->s_rdpkt(ssh
, data
, datalen
);
2526 ssh
->protocol(ssh
, NULL
, 0, pktin
);
2527 ssh_free_packet(pktin
);
2531 static void ssh_queue_incoming_data(Ssh ssh
,
2532 unsigned char **data
, int *datalen
)
2534 bufchain_add(&ssh
->queued_incoming_data
, *data
, *datalen
);
2539 static void ssh_process_queued_incoming_data(Ssh ssh
)
2542 unsigned char *data
;
2545 while (!ssh
->frozen
&& bufchain_size(&ssh
->queued_incoming_data
)) {
2546 bufchain_prefix(&ssh
->queued_incoming_data
, &vdata
, &len
);
2550 while (!ssh
->frozen
&& len
> 0)
2551 ssh_process_incoming_data(ssh
, &data
, &len
);
2554 bufchain_consume(&ssh
->queued_incoming_data
, origlen
- len
);
2558 static void ssh_set_frozen(Ssh ssh
, int frozen
)
2561 sk_set_frozen(ssh
->s
, frozen
);
2562 ssh
->frozen
= frozen
;
2565 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2567 /* Log raw data, if we're in that mode. */
2568 log_packet(ssh
->logctx
, PKT_INCOMING
, -1, NULL
, data
, datalen
, 0, NULL
);
2570 crBegin(ssh
->ssh_gotdata_crstate
);
2573 * To begin with, feed the characters one by one to the
2574 * protocol initialisation / selection function do_ssh_init().
2575 * When that returns 0, we're done with the initial greeting
2576 * exchange and can move on to packet discipline.
2579 int ret
; /* need not be kept across crReturn */
2581 crReturnV
; /* more data please */
2582 ret
= do_ssh_init(ssh
, *data
);
2590 * We emerge from that loop when the initial negotiation is
2591 * over and we have selected an s_rdpkt function. Now pass
2592 * everything to s_rdpkt, and then pass the resulting packets
2593 * to the proper protocol handler.
2597 while (bufchain_size(&ssh
->queued_incoming_data
) > 0 || datalen
> 0) {
2599 ssh_queue_incoming_data(ssh
, &data
, &datalen
);
2600 /* This uses up all data and cannot cause anything interesting
2601 * to happen; indeed, for anything to happen at all, we must
2602 * return, so break out. */
2604 } else if (bufchain_size(&ssh
->queued_incoming_data
) > 0) {
2605 /* This uses up some or all data, and may freeze the
2607 ssh_process_queued_incoming_data(ssh
);
2609 /* This uses up some or all data, and may freeze the
2611 ssh_process_incoming_data(ssh
, &data
, &datalen
);
2613 /* FIXME this is probably EBW. */
2614 if (ssh
->state
== SSH_STATE_CLOSED
)
2617 /* We're out of data. Go and get some more. */
2623 static int ssh_do_close(Ssh ssh
, int notify_exit
)
2626 struct ssh_channel
*c
;
2628 ssh
->state
= SSH_STATE_CLOSED
;
2629 expire_timer_context(ssh
);
2634 notify_remote_exit(ssh
->frontend
);
2639 * Now we must shut down any port- and X-forwarded channels going
2640 * through this connection.
2642 if (ssh
->channels
) {
2643 while (NULL
!= (c
= index234(ssh
->channels
, 0))) {
2646 x11_close(c
->u
.x11
.s
);
2649 pfd_close(c
->u
.pfd
.s
);
2652 del234(ssh
->channels
, c
); /* moving next one to index 0 */
2653 if (ssh
->version
== 2)
2654 bufchain_clear(&c
->v
.v2
.outbuffer
);
2659 * Go through port-forwardings, and close any associated
2660 * listening sockets.
2662 if (ssh
->portfwds
) {
2663 struct ssh_portfwd
*pf
;
2664 while (NULL
!= (pf
= index234(ssh
->portfwds
, 0))) {
2665 /* Dispose of any listening socket. */
2667 pfd_terminate(pf
->local
);
2668 del234(ssh
->portfwds
, pf
); /* moving next one to index 0 */
2676 static void ssh_log(Plug plug
, int type
, SockAddr addr
, int port
,
2677 const char *error_msg
, int error_code
)
2679 Ssh ssh
= (Ssh
) plug
;
2680 char addrbuf
[256], *msg
;
2682 sk_getaddr(addr
, addrbuf
, lenof(addrbuf
));
2685 msg
= dupprintf("Connecting to %s port %d", addrbuf
, port
);
2687 msg
= dupprintf("Failed to connect to %s: %s", addrbuf
, error_msg
);
2693 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2696 Ssh ssh
= (Ssh
) plug
;
2697 int need_notify
= ssh_do_close(ssh
, FALSE
);
2700 if (!ssh
->close_expected
)
2701 error_msg
= "Server unexpectedly closed network connection";
2703 error_msg
= "Server closed network connection";
2706 if (ssh
->close_expected
&& ssh
->clean_exit
&& ssh
->exitcode
< 0)
2710 notify_remote_exit(ssh
->frontend
);
2713 logevent(error_msg
);
2714 if (!ssh
->close_expected
|| !ssh
->clean_exit
)
2715 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2719 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2721 Ssh ssh
= (Ssh
) plug
;
2722 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2723 if (ssh
->state
== SSH_STATE_CLOSED
) {
2724 ssh_do_close(ssh
, TRUE
);
2730 static void ssh_sent(Plug plug
, int bufsize
)
2732 Ssh ssh
= (Ssh
) plug
;
2734 * If the send backlog on the SSH socket itself clears, we
2735 * should unthrottle the whole world if it was throttled.
2737 if (bufsize
< SSH_MAX_BACKLOG
)
2738 ssh_throttle_all(ssh
, 0, bufsize
);
2742 * Connect to specified host and port.
2743 * Returns an error message, or NULL on success.
2744 * Also places the canonical host name into `realhost'. It must be
2745 * freed by the caller.
2747 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2748 char **realhost
, int nodelay
, int keepalive
)
2750 static const struct plug_function_table fn_table
= {
2761 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2762 strcpy(ssh
->savedhost
, host
);
2765 port
= 22; /* default ssh port */
2766 ssh
->savedport
= port
;
2771 logeventf(ssh
, "Looking up host \"%s\"%s", host
,
2772 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV4 ?
" (IPv4)" :
2773 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV6 ?
" (IPv6)" : "")));
2774 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
,
2775 ssh
->cfg
.addressfamily
);
2776 if ((err
= sk_addr_error(addr
)) != NULL
) {
2784 ssh
->fn
= &fn_table
;
2785 ssh
->s
= new_connection(addr
, *realhost
, port
,
2786 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2787 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2789 notify_remote_exit(ssh
->frontend
);
2797 * Throttle or unthrottle the SSH connection.
2799 static void ssh1_throttle(Ssh ssh
, int adjust
)
2801 int old_count
= ssh
->v1_throttle_count
;
2802 ssh
->v1_throttle_count
+= adjust
;
2803 assert(ssh
->v1_throttle_count
>= 0);
2804 if (ssh
->v1_throttle_count
&& !old_count
) {
2805 ssh_set_frozen(ssh
, 1);
2806 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2807 ssh_set_frozen(ssh
, 0);
2812 * Throttle or unthrottle _all_ local data streams (for when sends
2813 * on the SSH connection itself back up).
2815 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2818 struct ssh_channel
*c
;
2820 if (enable
== ssh
->throttled_all
)
2822 ssh
->throttled_all
= enable
;
2823 ssh
->overall_bufsize
= bufsize
;
2826 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2828 case CHAN_MAINSESSION
:
2830 * This is treated separately, outside the switch.
2834 x11_override_throttle(c
->u
.x11
.s
, enable
);
2837 /* Agent channels require no buffer management. */
2840 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2846 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2848 Ssh ssh
= (Ssh
) sshv
;
2850 ssh
->agent_response
= reply
;
2851 ssh
->agent_response_len
= replylen
;
2853 if (ssh
->version
== 1)
2854 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2856 do_ssh2_authconn(ssh
, NULL
, -1, NULL
);
2859 static void ssh_dialog_callback(void *sshv
, int ret
)
2861 Ssh ssh
= (Ssh
) sshv
;
2863 ssh
->user_response
= ret
;
2865 if (ssh
->version
== 1)
2866 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2868 do_ssh2_transport(ssh
, NULL
, -1, NULL
);
2871 * This may have unfrozen the SSH connection, so do a
2874 ssh_process_queued_incoming_data(ssh
);
2877 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2879 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2881 void *sentreply
= reply
;
2884 /* Fake SSH_AGENT_FAILURE. */
2885 sentreply
= "\0\0\0\1\5";
2888 if (ssh
->version
== 2) {
2889 ssh2_add_channel_data(c
, sentreply
, replylen
);
2892 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2893 PKT_INT
, c
->remoteid
,
2896 PKT_DATA
, sentreply
, replylen
,
2905 * Client-initiated disconnection. Send a DISCONNECT if `wire_reason'
2906 * non-NULL, otherwise just close the connection. `client_reason' == NULL
2907 * => log `wire_reason'.
2909 static void ssh_disconnect(Ssh ssh
, char *client_reason
, char *wire_reason
,
2910 int code
, int clean_exit
)
2914 client_reason
= wire_reason
;
2916 error
= dupprintf("Disconnected: %s", client_reason
);
2918 error
= dupstr("Disconnected");
2920 if (ssh
->version
== 1) {
2921 send_packet(ssh
, SSH1_MSG_DISCONNECT
, PKT_STR
, wire_reason
,
2923 } else if (ssh
->version
== 2) {
2924 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
2925 ssh2_pkt_adduint32(pktout
, code
);
2926 ssh2_pkt_addstring(pktout
, wire_reason
);
2927 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
2928 ssh2_pkt_send_noqueue(ssh
, pktout
);
2931 ssh
->close_expected
= TRUE
;
2932 ssh
->clean_exit
= clean_exit
;
2933 ssh_closing((Plug
)ssh
, error
, 0, 0);
2938 * Handle the key exchange and user authentication phases.
2940 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
2941 struct Packet
*pktin
)
2944 unsigned char cookie
[8], *ptr
;
2945 struct RSAKey servkey
, hostkey
;
2946 struct MD5Context md5c
;
2947 struct do_ssh1_login_state
{
2949 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2950 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2951 int tried_publickey
, tried_agent
;
2952 int tis_auth_refused
, ccard_auth_refused
;
2953 unsigned char session_id
[16];
2956 void *publickey_blob
;
2957 int publickey_bloblen
;
2958 char *publickey_comment
;
2959 int publickey_encrypted
;
2960 prompts_t
*cur_prompt
;
2963 unsigned char request
[5], *response
, *p
;
2973 crState(do_ssh1_login_state
);
2975 crBegin(ssh
->do_ssh1_login_crstate
);
2980 if (pktin
->type
!= SSH1_SMSG_PUBLIC_KEY
) {
2981 bombout(("Public key packet not received"));
2985 logevent("Received public keys");
2987 ptr
= ssh_pkt_getdata(pktin
, 8);
2989 bombout(("SSH-1 public key packet stopped before random cookie"));
2992 memcpy(cookie
, ptr
, 8);
2994 if (!ssh1_pkt_getrsakey(pktin
, &servkey
, &s
->keystr1
) ||
2995 !ssh1_pkt_getrsakey(pktin
, &hostkey
, &s
->keystr2
)) {
2996 bombout(("Failed to read SSH-1 public keys from public key packet"));
3001 * Log the host key fingerprint.
3005 logevent("Host key fingerprint is:");
3006 strcpy(logmsg
, " ");
3007 hostkey
.comment
= NULL
;
3008 rsa_fingerprint(logmsg
+ strlen(logmsg
),
3009 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
3013 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(pktin
);
3014 s
->supported_ciphers_mask
= ssh_pkt_getuint32(pktin
);
3015 s
->supported_auths_mask
= ssh_pkt_getuint32(pktin
);
3017 ssh
->v1_local_protoflags
=
3018 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
3019 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
3022 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
3023 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
3024 MD5Update(&md5c
, cookie
, 8);
3025 MD5Final(s
->session_id
, &md5c
);
3027 for (i
= 0; i
< 32; i
++)
3028 ssh
->session_key
[i
] = random_byte();
3031 * Verify that the `bits' and `bytes' parameters match.
3033 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
3034 servkey
.bits
> servkey
.bytes
* 8) {
3035 bombout(("SSH-1 public keys were badly formatted"));
3039 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
3041 s
->rsabuf
= snewn(s
->len
, unsigned char);
3044 * Verify the host key.
3048 * First format the key into a string.
3050 int len
= rsastr_len(&hostkey
);
3051 char fingerprint
[100];
3052 char *keystr
= snewn(len
, char);
3053 rsastr_fmt(keystr
, &hostkey
);
3054 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
3056 ssh_set_frozen(ssh
, 1);
3057 s
->dlgret
= verify_ssh_host_key(ssh
->frontend
,
3058 ssh
->savedhost
, ssh
->savedport
,
3059 "rsa", keystr
, fingerprint
,
3060 ssh_dialog_callback
, ssh
);
3062 if (s
->dlgret
< 0) {
3066 bombout(("Unexpected data from server while waiting"
3067 " for user host key response"));
3070 } while (pktin
|| inlen
> 0);
3071 s
->dlgret
= ssh
->user_response
;
3073 ssh_set_frozen(ssh
, 0);
3075 if (s
->dlgret
== 0) {
3076 ssh_disconnect(ssh
, "User aborted at host key verification",
3082 for (i
= 0; i
< 32; i
++) {
3083 s
->rsabuf
[i
] = ssh
->session_key
[i
];
3085 s
->rsabuf
[i
] ^= s
->session_id
[i
];
3088 if (hostkey
.bytes
> servkey
.bytes
) {
3089 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
3091 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
3093 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
3095 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
3098 bombout(("SSH-1 public key encryptions failed due to bad formatting"));
3102 logevent("Encrypted session key");
3105 int cipher_chosen
= 0, warn
= 0;
3106 char *cipher_string
= NULL
;
3108 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
3109 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
3110 if (next_cipher
== CIPHER_WARN
) {
3111 /* If/when we choose a cipher, warn about it */
3113 } else if (next_cipher
== CIPHER_AES
) {
3114 /* XXX Probably don't need to mention this. */
3115 logevent("AES not supported in SSH-1, skipping");
3117 switch (next_cipher
) {
3118 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
3119 cipher_string
= "3DES"; break;
3120 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
3121 cipher_string
= "Blowfish"; break;
3122 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
3123 cipher_string
= "single-DES"; break;
3125 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
3129 if (!cipher_chosen
) {
3130 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
3131 bombout(("Server violates SSH-1 protocol by not "
3132 "supporting 3DES encryption"));
3134 /* shouldn't happen */
3135 bombout(("No supported ciphers found"));
3139 /* Warn about chosen cipher if necessary. */
3141 ssh_set_frozen(ssh
, 1);
3142 s
->dlgret
= askalg(ssh
->frontend
, "cipher", cipher_string
,
3143 ssh_dialog_callback
, ssh
);
3144 if (s
->dlgret
< 0) {
3148 bombout(("Unexpected data from server while waiting"
3149 " for user response"));
3152 } while (pktin
|| inlen
> 0);
3153 s
->dlgret
= ssh
->user_response
;
3155 ssh_set_frozen(ssh
, 0);
3156 if (s
->dlgret
== 0) {
3157 ssh_disconnect(ssh
, "User aborted at cipher warning", NULL
,
3164 switch (s
->cipher_type
) {
3165 case SSH_CIPHER_3DES
:
3166 logevent("Using 3DES encryption");
3168 case SSH_CIPHER_DES
:
3169 logevent("Using single-DES encryption");
3171 case SSH_CIPHER_BLOWFISH
:
3172 logevent("Using Blowfish encryption");
3176 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
3177 PKT_CHAR
, s
->cipher_type
,
3178 PKT_DATA
, cookie
, 8,
3179 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
3180 PKT_DATA
, s
->rsabuf
, s
->len
,
3181 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
3183 logevent("Trying to enable encryption...");
3187 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
3188 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
3190 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
3191 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
3192 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
3194 ssh
->crcda_ctx
= crcda_make_context();
3195 logevent("Installing CRC compensation attack detector");
3197 if (servkey
.modulus
) {
3198 sfree(servkey
.modulus
);
3199 servkey
.modulus
= NULL
;
3201 if (servkey
.exponent
) {
3202 sfree(servkey
.exponent
);
3203 servkey
.exponent
= NULL
;
3205 if (hostkey
.modulus
) {
3206 sfree(hostkey
.modulus
);
3207 hostkey
.modulus
= NULL
;
3209 if (hostkey
.exponent
) {
3210 sfree(hostkey
.exponent
);
3211 hostkey
.exponent
= NULL
;
3215 if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3216 bombout(("Encryption not successfully enabled"));
3220 logevent("Successfully started encryption");
3222 fflush(stdout
); /* FIXME eh? */
3224 if (!*ssh
->cfg
.username
) {
3225 int ret
; /* need not be kept over crReturn */
3226 s
->cur_prompt
= new_prompts(ssh
->frontend
);
3227 s
->cur_prompt
->to_server
= TRUE
;
3228 s
->cur_prompt
->name
= dupstr("SSH login name");
3229 add_prompt(s
->cur_prompt
, dupstr("login as: "), TRUE
,
3230 lenof(s
->username
));
3231 ret
= get_userpass_input(s
->cur_prompt
, NULL
, 0);
3234 crWaitUntil(!pktin
);
3235 ret
= get_userpass_input(s
->cur_prompt
, in
, inlen
);
3240 * Failed to get a username. Terminate.
3242 free_prompts(s
->cur_prompt
);
3243 ssh_disconnect(ssh
, "No username provided", NULL
, 0, TRUE
);
3246 memcpy(s
->username
, s
->cur_prompt
->prompts
[0]->result
,
3247 lenof(s
->username
));
3248 free_prompts(s
->cur_prompt
);
3250 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
3251 s
->username
[sizeof(s
->username
)-1] = '\0';
3254 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
3256 char *userlog
= dupprintf("Sent username \"%s\"", s
->username
);
3258 if (flags
& FLAG_INTERACTIVE
&&
3259 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
3260 c_write_str(ssh
, userlog
);
3261 c_write_str(ssh
, "\r\n");
3269 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
3270 /* We must not attempt PK auth. Pretend we've already tried it. */
3271 s
->tried_publickey
= s
->tried_agent
= 1;
3273 s
->tried_publickey
= s
->tried_agent
= 0;
3275 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
3277 * Load the public half of any configured keyfile for later use.
3279 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
3281 logeventf(ssh
, "Reading private key file \"%.150s\"",
3282 filename_to_str(&ssh
->cfg
.keyfile
));
3283 keytype
= key_type(&ssh
->cfg
.keyfile
);
3284 if (keytype
== SSH_KEYTYPE_SSH1
) {
3286 if (rsakey_pubblob(&ssh
->cfg
.keyfile
,
3287 &s
->publickey_blob
, &s
->publickey_bloblen
,
3288 &s
->publickey_comment
, &error
)) {
3289 s
->publickey_encrypted
= rsakey_encrypted(&ssh
->cfg
.keyfile
,
3293 logeventf(ssh
, "Unable to load private key (%s)", error
);
3294 msgbuf
= dupprintf("Unable to load private key file "
3295 "\"%.150s\" (%s)\r\n",
3296 filename_to_str(&ssh
->cfg
.keyfile
),
3298 c_write_str(ssh
, msgbuf
);
3300 s
->publickey_blob
= NULL
;
3304 logeventf(ssh
, "Unable to use this key file (%s)",
3305 key_type_to_str(keytype
));
3306 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
3308 filename_to_str(&ssh
->cfg
.keyfile
),
3309 key_type_to_str(keytype
));
3310 c_write_str(ssh
, msgbuf
);
3312 s
->publickey_blob
= NULL
;
3315 s
->publickey_blob
= NULL
;
3317 while (pktin
->type
== SSH1_SMSG_FAILURE
) {
3318 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
3320 if (ssh
->cfg
.tryagent
&& agent_exists() && !s
->tried_agent
) {
3322 * Attempt RSA authentication using Pageant.
3328 logevent("Pageant is running. Requesting keys.");
3330 /* Request the keys held by the agent. */
3331 PUT_32BIT(s
->request
, 1);
3332 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
3333 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
3334 ssh_agent_callback
, ssh
)) {
3338 bombout(("Unexpected data from server while waiting"
3339 " for agent response"));
3342 } while (pktin
|| inlen
> 0);
3343 r
= ssh
->agent_response
;
3344 s
->responselen
= ssh
->agent_response_len
;
3346 s
->response
= (unsigned char *) r
;
3347 if (s
->response
&& s
->responselen
>= 5 &&
3348 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
3349 s
->p
= s
->response
+ 5;
3350 s
->nkeys
= GET_32BIT(s
->p
);
3352 logeventf(ssh
, "Pageant has %d SSH-1 keys", s
->nkeys
);
3353 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
3354 unsigned char *pkblob
= s
->p
;
3358 do { /* do while (0) to make breaking easy */
3359 n
= ssh1_read_bignum
3360 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3365 n
= ssh1_read_bignum
3366 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3371 if (s
->responselen
- (s
->p
-s
->response
) < 4)
3373 s
->commentlen
= GET_32BIT(s
->p
);
3375 if (s
->responselen
- (s
->p
-s
->response
) <
3378 s
->commentp
= (char *)s
->p
;
3379 s
->p
+= s
->commentlen
;
3383 logevent("Pageant key list packet was truncated");
3387 if (s
->publickey_blob
) {
3388 if (!memcmp(pkblob
, s
->publickey_blob
,
3389 s
->publickey_bloblen
)) {
3390 logeventf(ssh
, "Pageant key #%d matches "
3391 "configured key file", s
->keyi
);
3392 s
->tried_publickey
= 1;
3394 /* Skip non-configured key */
3397 logeventf(ssh
, "Trying Pageant key #%d", s
->keyi
);
3398 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3399 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3401 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3402 logevent("Key refused");
3405 logevent("Received RSA challenge");
3406 if ((s
->challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3407 bombout(("Server's RSA challenge was badly formatted"));
3412 char *agentreq
, *q
, *ret
;
3415 len
= 1 + 4; /* message type, bit count */
3416 len
+= ssh1_bignum_length(s
->key
.exponent
);
3417 len
+= ssh1_bignum_length(s
->key
.modulus
);
3418 len
+= ssh1_bignum_length(s
->challenge
);
3419 len
+= 16; /* session id */
3420 len
+= 4; /* response format */
3421 agentreq
= snewn(4 + len
, char);
3422 PUT_32BIT(agentreq
, len
);
3424 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
3425 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
3427 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
3428 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
3429 q
+= ssh1_write_bignum(q
, s
->challenge
);
3430 memcpy(q
, s
->session_id
, 16);
3432 PUT_32BIT(q
, 1); /* response format */
3433 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
3434 ssh_agent_callback
, ssh
)) {
3439 bombout(("Unexpected data from server"
3440 " while waiting for agent"
3444 } while (pktin
|| inlen
> 0);
3445 vret
= ssh
->agent_response
;
3446 retlen
= ssh
->agent_response_len
;
3451 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
3452 logevent("Sending Pageant's response");
3453 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3454 PKT_DATA
, ret
+ 5, 16,
3458 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
3460 ("Pageant's response accepted");
3461 if (flags
& FLAG_VERBOSE
) {
3462 c_write_str(ssh
, "Authenticated using"
3464 c_write(ssh
, s
->commentp
,
3466 c_write_str(ssh
, "\" from agent\r\n");
3471 ("Pageant's response not accepted");
3474 ("Pageant failed to answer challenge");
3478 logevent("No reply received from Pageant");
3481 freebn(s
->key
.exponent
);
3482 freebn(s
->key
.modulus
);
3483 freebn(s
->challenge
);
3488 if (s
->publickey_blob
&& !s
->tried_publickey
)
3489 logevent("Configured key file not in Pageant");
3494 if (s
->publickey_blob
&& !s
->tried_publickey
) {
3496 * Try public key authentication with the specified
3499 int got_passphrase
; /* need not be kept over crReturn */
3500 if (flags
& FLAG_VERBOSE
)
3501 c_write_str(ssh
, "Trying public key authentication.\r\n");
3502 logeventf(ssh
, "Trying public key \"%s\"",
3503 filename_to_str(&ssh
->cfg
.keyfile
));
3504 s
->tried_publickey
= 1;
3505 got_passphrase
= FALSE
;
3506 while (!got_passphrase
) {
3508 * Get a passphrase, if necessary.
3510 char *passphrase
= NULL
; /* only written after crReturn */
3512 if (!s
->publickey_encrypted
) {
3513 if (flags
& FLAG_VERBOSE
)
3514 c_write_str(ssh
, "No passphrase required.\r\n");
3517 int ret
; /* need not be kept over crReturn */
3518 s
->cur_prompt
= new_prompts(ssh
->frontend
);
3519 s
->cur_prompt
->to_server
= FALSE
;
3520 s
->cur_prompt
->name
= dupstr("SSH key passphrase");
3521 add_prompt(s
->cur_prompt
,
3522 dupprintf("Passphrase for key \"%.100s\": ",
3523 s
->publickey_comment
),
3524 FALSE
, SSH_MAX_PASSWORD_LEN
);
3525 ret
= get_userpass_input(s
->cur_prompt
, NULL
, 0);
3528 crWaitUntil(!pktin
);
3529 ret
= get_userpass_input(s
->cur_prompt
, in
, inlen
);
3533 /* Failed to get a passphrase. Terminate. */
3534 free_prompts(s
->cur_prompt
);
3535 ssh_disconnect(ssh
, NULL
, "Unable to authenticate",
3539 passphrase
= dupstr(s
->cur_prompt
->prompts
[0]->result
);
3540 free_prompts(s
->cur_prompt
);
3543 * Try decrypting key with passphrase.
3545 ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, passphrase
,
3548 memset(passphrase
, 0, strlen(passphrase
));
3552 /* Correct passphrase. */
3553 got_passphrase
= TRUE
;
3554 } else if (ret
== 0) {
3555 c_write_str(ssh
, "Couldn't load private key from ");
3556 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3557 c_write_str(ssh
, " (");
3558 c_write_str(ssh
, error
);
3559 c_write_str(ssh
, ").\r\n");
3560 got_passphrase
= FALSE
;
3561 break; /* go and try something else */
3562 } else if (ret
== -1) {
3563 c_write_str(ssh
, "Wrong passphrase.\r\n"); /* FIXME */
3564 got_passphrase
= FALSE
;
3567 assert(0 && "unexpected return from loadrsakey()");
3568 got_passphrase
= FALSE
; /* placate optimisers */
3572 if (got_passphrase
) {
3575 * Send a public key attempt.
3577 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3578 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3581 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3582 c_write_str(ssh
, "Server refused our public key.\r\n");
3583 continue; /* go and try something else */
3585 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3586 bombout(("Bizarre response to offer of public key"));
3592 unsigned char buffer
[32];
3593 Bignum challenge
, response
;
3595 if ((challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3596 bombout(("Server's RSA challenge was badly formatted"));
3599 response
= rsadecrypt(challenge
, &s
->key
);
3600 freebn(s
->key
.private_exponent
);/* burn the evidence */
3602 for (i
= 0; i
< 32; i
++) {
3603 buffer
[i
] = bignum_byte(response
, 31 - i
);
3607 MD5Update(&md5c
, buffer
, 32);
3608 MD5Update(&md5c
, s
->session_id
, 16);
3609 MD5Final(buffer
, &md5c
);
3611 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3612 PKT_DATA
, buffer
, 16, PKT_END
);
3619 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3620 if (flags
& FLAG_VERBOSE
)
3621 c_write_str(ssh
, "Failed to authenticate with"
3622 " our public key.\r\n");
3623 continue; /* go and try something else */
3624 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3625 bombout(("Bizarre response to RSA authentication response"));
3629 break; /* we're through! */
3635 * Otherwise, try various forms of password-like authentication.
3637 s
->cur_prompt
= new_prompts(ssh
->frontend
);
3639 if (ssh
->cfg
.try_tis_auth
&&
3640 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3641 !s
->tis_auth_refused
) {
3642 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3643 logevent("Requested TIS authentication");
3644 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3646 if (pktin
->type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3647 logevent("TIS authentication declined");
3648 if (flags
& FLAG_INTERACTIVE
)
3649 c_write_str(ssh
, "TIS authentication refused.\r\n");
3650 s
->tis_auth_refused
= 1;
3655 char *instr_suf
, *prompt
;
3657 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3659 bombout(("TIS challenge packet was badly formed"));
3662 logevent("Received TIS challenge");
3663 s
->cur_prompt
->to_server
= TRUE
;
3664 s
->cur_prompt
->name
= dupstr("SSH TIS authentication");
3665 /* Prompt heuristic comes from OpenSSH */
3666 if (memchr(challenge
, '\n', challengelen
)) {
3667 instr_suf
= dupstr("");
3668 prompt
= dupprintf("%.*s", challengelen
, challenge
);
3670 instr_suf
= dupprintf("%.*s", challengelen
, challenge
);
3671 prompt
= dupstr("Response: ");
3673 s
->cur_prompt
->instruction
=
3674 dupprintf("Using TIS authentication.%s%s",
3675 (*instr_suf
) ?
"\n" : "",
3677 s
->cur_prompt
->instr_reqd
= TRUE
;
3678 add_prompt(s
->cur_prompt
, prompt
, FALSE
, SSH_MAX_PASSWORD_LEN
);
3682 if (ssh
->cfg
.try_tis_auth
&&
3683 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3684 !s
->ccard_auth_refused
) {
3685 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3686 logevent("Requested CryptoCard authentication");
3687 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3689 if (pktin
->type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3690 logevent("CryptoCard authentication declined");
3691 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3692 s
->ccard_auth_refused
= 1;
3697 char *instr_suf
, *prompt
;
3699 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3701 bombout(("CryptoCard challenge packet was badly formed"));
3704 logevent("Received CryptoCard challenge");
3705 s
->cur_prompt
->to_server
= TRUE
;
3706 s
->cur_prompt
->name
= dupstr("SSH CryptoCard authentication");
3707 s
->cur_prompt
->name_reqd
= FALSE
;
3708 /* Prompt heuristic comes from OpenSSH */
3709 if (memchr(challenge
, '\n', challengelen
)) {
3710 instr_suf
= dupstr("");
3711 prompt
= dupprintf("%.*s", challengelen
, challenge
);
3713 instr_suf
= dupprintf("%.*s", challengelen
, challenge
);
3714 prompt
= dupstr("Response: ");
3716 s
->cur_prompt
->instruction
=
3717 dupprintf("Using CryptoCard authentication.%s%s",
3718 (*instr_suf
) ?
"\n" : "",
3720 s
->cur_prompt
->instr_reqd
= TRUE
;
3721 add_prompt(s
->cur_prompt
, prompt
, FALSE
, SSH_MAX_PASSWORD_LEN
);
3725 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3726 s
->cur_prompt
->to_server
= TRUE
;
3727 s
->cur_prompt
->name
= dupstr("SSH password");
3728 add_prompt(s
->cur_prompt
, dupprintf("%.90s@%.90s's password: ",
3729 s
->username
, ssh
->savedhost
),
3730 FALSE
, SSH_MAX_PASSWORD_LEN
);
3734 * Show password prompt, having first obtained it via a TIS
3735 * or CryptoCard exchange if we're doing TIS or CryptoCard
3739 int ret
; /* need not be kept over crReturn */
3740 ret
= get_userpass_input(s
->cur_prompt
, NULL
, 0);
3743 crWaitUntil(!pktin
);
3744 ret
= get_userpass_input(s
->cur_prompt
, in
, inlen
);
3749 * Failed to get a password (for example
3750 * because one was supplied on the command line
3751 * which has already failed to work). Terminate.
3753 free_prompts(s
->cur_prompt
);
3754 ssh_disconnect(ssh
, NULL
, "Unable to authenticate", 0, TRUE
);
3759 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3761 * Defence against traffic analysis: we send a
3762 * whole bunch of packets containing strings of
3763 * different lengths. One of these strings is the
3764 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3765 * The others are all random data in
3766 * SSH1_MSG_IGNORE packets. This way a passive
3767 * listener can't tell which is the password, and
3768 * hence can't deduce the password length.
3770 * Anybody with a password length greater than 16
3771 * bytes is going to have enough entropy in their
3772 * password that a listener won't find it _that_
3773 * much help to know how long it is. So what we'll
3776 * - if password length < 16, we send 15 packets
3777 * containing string lengths 1 through 15
3779 * - otherwise, we let N be the nearest multiple
3780 * of 8 below the password length, and send 8
3781 * packets containing string lengths N through
3782 * N+7. This won't obscure the order of
3783 * magnitude of the password length, but it will
3784 * introduce a bit of extra uncertainty.
3786 * A few servers can't deal with SSH1_MSG_IGNORE, at
3787 * least in this context. For these servers, we need
3788 * an alternative defence. We make use of the fact
3789 * that the password is interpreted as a C string:
3790 * so we can append a NUL, then some random data.
3792 * A few servers can deal with neither SSH1_MSG_IGNORE
3793 * here _nor_ a padded password string.
3794 * For these servers we are left with no defences
3795 * against password length sniffing.
3797 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
) &&
3798 !(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3800 * The server can deal with SSH1_MSG_IGNORE, so
3801 * we can use the primary defence.
3803 int bottom
, top
, pwlen
, i
;
3806 pwlen
= strlen(s
->cur_prompt
->prompts
[0]->result
);
3808 bottom
= 0; /* zero length passwords are OK! :-) */
3811 bottom
= pwlen
& ~7;
3815 assert(pwlen
>= bottom
&& pwlen
<= top
);
3817 randomstr
= snewn(top
+ 1, char);
3819 for (i
= bottom
; i
<= top
; i
++) {
3821 defer_packet(ssh
, s
->pwpkt_type
,
3822 PKTT_PASSWORD
, PKT_STR
,
3823 s
->cur_prompt
->prompts
[0]->result
,
3824 PKTT_OTHER
, PKT_END
);
3826 for (j
= 0; j
< i
; j
++) {
3828 randomstr
[j
] = random_byte();
3829 } while (randomstr
[j
] == '\0');
3831 randomstr
[i
] = '\0';
3832 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3833 PKT_STR
, randomstr
, PKT_END
);
3836 logevent("Sending password with camouflage packets");
3837 ssh_pkt_defersend(ssh
);
3840 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3842 * The server can't deal with SSH1_MSG_IGNORE
3843 * but can deal with padded passwords, so we
3844 * can use the secondary defence.
3850 len
= strlen(s
->cur_prompt
->prompts
[0]->result
);
3851 if (len
< sizeof(string
)) {
3853 strcpy(string
, s
->cur_prompt
->prompts
[0]->result
);
3854 len
++; /* cover the zero byte */
3855 while (len
< sizeof(string
)) {
3856 string
[len
++] = (char) random_byte();
3859 ss
= s
->cur_prompt
->prompts
[0]->result
;
3861 logevent("Sending length-padded password");
3862 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3863 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3864 PKTT_OTHER
, PKT_END
);
3867 * The server is believed unable to cope with
3868 * any of our password camouflage methods.
3871 len
= strlen(s
->cur_prompt
->prompts
[0]->result
);
3872 logevent("Sending unpadded password");
3873 send_packet(ssh
, s
->pwpkt_type
,
3874 PKTT_PASSWORD
, PKT_INT
, len
,
3875 PKT_DATA
, s
->cur_prompt
->prompts
[0]->result
, len
,
3876 PKTT_OTHER
, PKT_END
);
3879 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3880 PKT_STR
, s
->cur_prompt
->prompts
[0]->result
,
3881 PKTT_OTHER
, PKT_END
);
3883 logevent("Sent password");
3884 free_prompts(s
->cur_prompt
);
3886 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3887 if (flags
& FLAG_VERBOSE
)
3888 c_write_str(ssh
, "Access denied\r\n");
3889 logevent("Authentication refused");
3890 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3891 bombout(("Strange packet received, type %d", pktin
->type
));
3897 if (s
->publickey_blob
) {
3898 sfree(s
->publickey_blob
);
3899 sfree(s
->publickey_comment
);
3902 logevent("Authentication successful");
3907 void sshfwd_close(struct ssh_channel
*c
)
3911 if (ssh
->state
== SSH_STATE_CLOSED
)
3914 if (c
&& !c
->closes
) {
3916 * If halfopen is true, we have sent
3917 * CHANNEL_OPEN for this channel, but it hasn't even been
3918 * acknowledged by the server. So we must set a close flag
3919 * on it now, and then when the server acks the channel
3920 * open, we can close it then.
3923 if (ssh
->version
== 1) {
3924 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3927 struct Packet
*pktout
;
3928 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3929 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
3930 ssh2_pkt_send(ssh
, pktout
);
3933 c
->closes
= 1; /* sent MSG_CLOSE */
3934 if (c
->type
== CHAN_X11
) {
3936 logevent("Forwarded X11 connection terminated");
3937 } else if (c
->type
== CHAN_SOCKDATA
||
3938 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3940 logevent("Forwarded port closed");
3945 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3949 if (ssh
->state
== SSH_STATE_CLOSED
)
3952 if (ssh
->version
== 1) {
3953 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3954 PKT_INT
, c
->remoteid
,
3956 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3957 PKTT_OTHER
, PKT_END
);
3959 * In SSH-1 we can return 0 here - implying that forwarded
3960 * connections are never individually throttled - because
3961 * the only circumstance that can cause throttling will be
3962 * the whole SSH connection backing up, in which case
3963 * _everything_ will be throttled as a whole.
3967 ssh2_add_channel_data(c
, buf
, len
);
3968 return ssh2_try_send(c
);
3972 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3976 if (ssh
->state
== SSH_STATE_CLOSED
)
3979 if (ssh
->version
== 1) {
3980 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3981 c
->v
.v1
.throttling
= 0;
3982 ssh1_throttle(ssh
, -1);
3985 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3989 static void ssh_queueing_handler(Ssh ssh
, struct Packet
*pktin
)
3991 struct queued_handler
*qh
= ssh
->qhead
;
3995 assert(pktin
->type
== qh
->msg1
|| pktin
->type
== qh
->msg2
);
3998 assert(ssh
->packet_dispatch
[qh
->msg1
] == ssh_queueing_handler
);
3999 ssh
->packet_dispatch
[qh
->msg1
] = NULL
;
4002 assert(ssh
->packet_dispatch
[qh
->msg2
] == ssh_queueing_handler
);
4003 ssh
->packet_dispatch
[qh
->msg2
] = NULL
;
4007 ssh
->qhead
= qh
->next
;
4009 if (ssh
->qhead
->msg1
> 0) {
4010 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg1
] == NULL
);
4011 ssh
->packet_dispatch
[ssh
->qhead
->msg1
] = ssh_queueing_handler
;
4013 if (ssh
->qhead
->msg2
> 0) {
4014 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg2
] == NULL
);
4015 ssh
->packet_dispatch
[ssh
->qhead
->msg2
] = ssh_queueing_handler
;
4018 ssh
->qhead
= ssh
->qtail
= NULL
;
4019 ssh
->packet_dispatch
[pktin
->type
] = NULL
;
4022 qh
->handler(ssh
, pktin
, qh
->ctx
);
4027 static void ssh_queue_handler(Ssh ssh
, int msg1
, int msg2
,
4028 chandler_fn_t handler
, void *ctx
)
4030 struct queued_handler
*qh
;
4032 qh
= snew(struct queued_handler
);
4035 qh
->handler
= handler
;
4039 if (ssh
->qtail
== NULL
) {
4043 assert(ssh
->packet_dispatch
[qh
->msg1
] == NULL
);
4044 ssh
->packet_dispatch
[qh
->msg1
] = ssh_queueing_handler
;
4047 assert(ssh
->packet_dispatch
[qh
->msg2
] == NULL
);
4048 ssh
->packet_dispatch
[qh
->msg2
] = ssh_queueing_handler
;
4051 ssh
->qtail
->next
= qh
;
4056 static void ssh_rportfwd_succfail(Ssh ssh
, struct Packet
*pktin
, void *ctx
)
4058 struct ssh_rportfwd
*rpf
, *pf
= (struct ssh_rportfwd
*)ctx
;
4060 if (pktin
->type
== (ssh
->version
== 1 ? SSH1_SMSG_SUCCESS
:
4061 SSH2_MSG_REQUEST_SUCCESS
)) {
4062 logeventf(ssh
, "Remote port forwarding from %s enabled",
4065 logeventf(ssh
, "Remote port forwarding from %s refused",
4068 rpf
= del234(ssh
->rportfwds
, pf
);
4074 static void ssh_setup_portfwd(Ssh ssh
, const Config
*cfg
)
4076 const char *portfwd_strptr
= cfg
->portfwd
;
4077 struct ssh_portfwd
*epf
;
4080 if (!ssh
->portfwds
) {
4081 ssh
->portfwds
= newtree234(ssh_portcmp
);
4084 * Go through the existing port forwardings and tag them
4085 * with status==DESTROY. Any that we want to keep will be
4086 * re-enabled (status==KEEP) as we go through the
4087 * configuration and find out which bits are the same as
4090 struct ssh_portfwd
*epf
;
4092 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
4093 epf
->status
= DESTROY
;
4096 while (*portfwd_strptr
) {
4097 char address_family
, type
;
4098 int sport
,dport
,sserv
,dserv
;
4099 char sports
[256], dports
[256], saddr
[256], host
[256];
4102 address_family
= 'A';
4104 if (*portfwd_strptr
== 'A' ||
4105 *portfwd_strptr
== '4' ||
4106 *portfwd_strptr
== '6')
4107 address_family
= *portfwd_strptr
++;
4108 if (*portfwd_strptr
== 'L' ||
4109 *portfwd_strptr
== 'R' ||
4110 *portfwd_strptr
== 'D')
4111 type
= *portfwd_strptr
++;
4116 while (*portfwd_strptr
&& *portfwd_strptr
!= '\t') {
4117 if (*portfwd_strptr
== ':') {
4119 * We've seen a colon in the middle of the
4120 * source port number. This means that
4121 * everything we've seen until now is the
4122 * source _address_, so we'll move it into
4123 * saddr and start sports from the beginning
4128 if (ssh
->version
== 1 && type
== 'R') {
4129 logeventf(ssh
, "SSH-1 cannot handle remote source address "
4130 "spec \"%s\"; ignoring", sports
);
4132 strcpy(saddr
, sports
);
4135 if (n
< lenof(sports
)-1) sports
[n
++] = *portfwd_strptr
++;
4139 if (*portfwd_strptr
== '\t')
4142 while (*portfwd_strptr
&& *portfwd_strptr
!= ':') {
4143 if (n
< lenof(host
)-1) host
[n
++] = *portfwd_strptr
++;
4146 if (*portfwd_strptr
== ':')
4149 while (*portfwd_strptr
) {
4150 if (n
< lenof(dports
)-1) dports
[n
++] = *portfwd_strptr
++;
4154 dport
= atoi(dports
);
4158 dport
= net_service_lookup(dports
);
4160 logeventf(ssh
, "Service lookup failed for destination"
4161 " port \"%s\"", dports
);
4165 while (*portfwd_strptr
) portfwd_strptr
++;
4169 portfwd_strptr
++; /* eat the NUL and move to next one */
4171 sport
= atoi(sports
);
4175 sport
= net_service_lookup(sports
);
4177 logeventf(ssh
, "Service lookup failed for source"
4178 " port \"%s\"", sports
);
4181 if (sport
&& dport
) {
4182 /* Set up a description of the source port. */
4183 struct ssh_portfwd
*pfrec
, *epfrec
;
4185 pfrec
= snew(struct ssh_portfwd
);
4187 pfrec
->saddr
= *saddr ?
dupstr(saddr
) : NULL
;
4188 pfrec
->sserv
= sserv ?
dupstr(sports
) : NULL
;
4189 pfrec
->sport
= sport
;
4190 pfrec
->daddr
= *host ?
dupstr(host
) : NULL
;
4191 pfrec
->dserv
= dserv ?
dupstr(dports
) : NULL
;
4192 pfrec
->dport
= dport
;
4193 pfrec
->local
= NULL
;
4194 pfrec
->remote
= NULL
;
4195 pfrec
->addressfamily
= (address_family
== '4' ? ADDRTYPE_IPV4
:
4196 address_family
== '6' ? ADDRTYPE_IPV6
:
4199 epfrec
= add234(ssh
->portfwds
, pfrec
);
4200 if (epfrec
!= pfrec
) {
4202 * We already have a port forwarding with precisely
4203 * these parameters. Hence, no need to do anything;
4204 * simply tag the existing one as KEEP.
4206 epfrec
->status
= KEEP
;
4207 free_portfwd(pfrec
);
4209 pfrec
->status
= CREATE
;
4215 * Now go through and destroy any port forwardings which were
4218 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
4219 if (epf
->status
== DESTROY
) {
4222 message
= dupprintf("%s port forwarding from %s%s%d",
4223 epf
->type
== 'L' ?
"local" :
4224 epf
->type
== 'R' ?
"remote" : "dynamic",
4225 epf
->saddr ? epf
->saddr
: "",
4226 epf
->saddr ?
":" : "",
4229 if (epf
->type
!= 'D') {
4230 char *msg2
= dupprintf("%s to %s:%d", message
,
4231 epf
->daddr
, epf
->dport
);
4236 logeventf(ssh
, "Cancelling %s", message
);
4240 struct ssh_rportfwd
*rpf
= epf
->remote
;
4241 struct Packet
*pktout
;
4244 * Cancel the port forwarding at the server
4247 if (ssh
->version
== 1) {
4249 * We cannot cancel listening ports on the
4250 * server side in SSH-1! There's no message
4251 * to support it. Instead, we simply remove
4252 * the rportfwd record from the local end
4253 * so that any connections the server tries
4254 * to make on it are rejected.
4257 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
4258 ssh2_pkt_addstring(pktout
, "cancel-tcpip-forward");
4259 ssh2_pkt_addbool(pktout
, 0);/* _don't_ want reply */
4261 ssh2_pkt_addstring(pktout
, epf
->saddr
);
4262 } else if (ssh
->cfg
.rport_acceptall
) {
4263 /* XXX: ssh->cfg.rport_acceptall may not represent
4264 * what was used to open the original connection,
4265 * since it's reconfigurable. */
4266 ssh2_pkt_addstring(pktout
, "0.0.0.0");
4268 ssh2_pkt_addstring(pktout
, "127.0.0.1");
4270 ssh2_pkt_adduint32(pktout
, epf
->sport
);
4271 ssh2_pkt_send(ssh
, pktout
);
4274 del234(ssh
->rportfwds
, rpf
);
4276 } else if (epf
->local
) {
4277 pfd_terminate(epf
->local
);
4280 delpos234(ssh
->portfwds
, i
);
4282 i
--; /* so we don't skip one in the list */
4286 * And finally, set up any new port forwardings (status==CREATE).
4288 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
4289 if (epf
->status
== CREATE
) {
4290 char *sportdesc
, *dportdesc
;
4291 sportdesc
= dupprintf("%s%s%s%s%d%s",
4292 epf
->saddr ? epf
->saddr
: "",
4293 epf
->saddr ?
":" : "",
4294 epf
->sserv ? epf
->sserv
: "",
4295 epf
->sserv ?
"(" : "",
4297 epf
->sserv ?
")" : "");
4298 if (epf
->type
== 'D') {
4301 dportdesc
= dupprintf("%s:%s%s%d%s",
4303 epf
->dserv ? epf
->dserv
: "",
4304 epf
->dserv ?
"(" : "",
4306 epf
->dserv ?
")" : "");
4309 if (epf
->type
== 'L') {
4310 const char *err
= pfd_addforward(epf
->daddr
, epf
->dport
,
4311 epf
->saddr
, epf
->sport
,
4314 epf
->addressfamily
);
4316 logeventf(ssh
, "Local %sport %s forwarding to %s%s%s",
4317 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
4318 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
4319 sportdesc
, dportdesc
,
4320 err ?
" failed: " : "", err ? err
: "");
4321 } else if (epf
->type
== 'D') {
4322 const char *err
= pfd_addforward(NULL
, -1,
4323 epf
->saddr
, epf
->sport
,
4326 epf
->addressfamily
);
4328 logeventf(ssh
, "Local %sport %s SOCKS dynamic forwarding%s%s",
4329 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
4330 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
4332 err ?
" failed: " : "", err ? err
: "");
4334 struct ssh_rportfwd
*pf
;
4337 * Ensure the remote port forwardings tree exists.
4339 if (!ssh
->rportfwds
) {
4340 if (ssh
->version
== 1)
4341 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
4343 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
4346 pf
= snew(struct ssh_rportfwd
);
4347 strncpy(pf
->dhost
, epf
->daddr
, lenof(pf
->dhost
)-1);
4348 pf
->dhost
[lenof(pf
->dhost
)-1] = '\0';
4349 pf
->dport
= epf
->dport
;
4350 pf
->sport
= epf
->sport
;
4351 if (add234(ssh
->rportfwds
, pf
) != pf
) {
4352 logeventf(ssh
, "Duplicate remote port forwarding to %s:%d",
4353 epf
->daddr
, epf
->dport
);
4356 logeventf(ssh
, "Requesting remote port %s"
4357 " forward to %s", sportdesc
, dportdesc
);
4359 pf
->sportdesc
= sportdesc
;
4364 if (ssh
->version
== 1) {
4365 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
4366 PKT_INT
, epf
->sport
,
4367 PKT_STR
, epf
->daddr
,
4368 PKT_INT
, epf
->dport
,
4370 ssh_queue_handler(ssh
, SSH1_SMSG_SUCCESS
,
4372 ssh_rportfwd_succfail
, pf
);
4374 struct Packet
*pktout
;
4375 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
4376 ssh2_pkt_addstring(pktout
, "tcpip-forward");
4377 ssh2_pkt_addbool(pktout
, 1);/* want reply */
4379 ssh2_pkt_addstring(pktout
, epf
->saddr
);
4380 } else if (cfg
->rport_acceptall
) {
4381 ssh2_pkt_addstring(pktout
, "0.0.0.0");
4383 ssh2_pkt_addstring(pktout
, "127.0.0.1");
4385 ssh2_pkt_adduint32(pktout
, epf
->sport
);
4386 ssh2_pkt_send(ssh
, pktout
);
4388 ssh_queue_handler(ssh
, SSH2_MSG_REQUEST_SUCCESS
,
4389 SSH2_MSG_REQUEST_FAILURE
,
4390 ssh_rportfwd_succfail
, pf
);
4399 static void ssh1_smsg_stdout_stderr_data(Ssh ssh
, struct Packet
*pktin
)
4402 int stringlen
, bufsize
;
4404 ssh_pkt_getstring(pktin
, &string
, &stringlen
);
4405 if (string
== NULL
) {
4406 bombout(("Incoming terminal data packet was badly formed"));
4410 bufsize
= from_backend(ssh
->frontend
, pktin
->type
== SSH1_SMSG_STDERR_DATA
,
4412 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4413 ssh
->v1_stdout_throttling
= 1;
4414 ssh1_throttle(ssh
, +1);
4418 static void ssh1_smsg_x11_open(Ssh ssh
, struct Packet
*pktin
)
4420 /* Remote side is trying to open a channel to talk to our
4421 * X-Server. Give them back a local channel number. */
4422 struct ssh_channel
*c
;
4423 int remoteid
= ssh_pkt_getuint32(pktin
);
4425 logevent("Received X11 connect request");
4426 /* Refuse if X11 forwarding is disabled. */
4427 if (!ssh
->X11_fwd_enabled
) {
4428 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4429 PKT_INT
, remoteid
, PKT_END
);
4430 logevent("Rejected X11 connect request");
4432 c
= snew(struct ssh_channel
);
4435 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
4436 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
4437 logevent("Opening X11 forward connection failed");
4439 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4440 PKT_INT
, remoteid
, PKT_END
);
4443 ("Opening X11 forward connection succeeded");
4444 c
->remoteid
= remoteid
;
4445 c
->halfopen
= FALSE
;
4446 c
->localid
= alloc_channel_id(ssh
);
4448 c
->v
.v1
.throttling
= 0;
4449 c
->type
= CHAN_X11
; /* identify channel type */
4450 add234(ssh
->channels
, c
);
4451 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4452 PKT_INT
, c
->remoteid
, PKT_INT
,
4453 c
->localid
, PKT_END
);
4454 logevent("Opened X11 forward channel");
4459 static void ssh1_smsg_agent_open(Ssh ssh
, struct Packet
*pktin
)
4461 /* Remote side is trying to open a channel to talk to our
4462 * agent. Give them back a local channel number. */
4463 struct ssh_channel
*c
;
4464 int remoteid
= ssh_pkt_getuint32(pktin
);
4466 /* Refuse if agent forwarding is disabled. */
4467 if (!ssh
->agentfwd_enabled
) {
4468 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4469 PKT_INT
, remoteid
, PKT_END
);
4471 c
= snew(struct ssh_channel
);
4473 c
->remoteid
= remoteid
;
4474 c
->halfopen
= FALSE
;
4475 c
->localid
= alloc_channel_id(ssh
);
4477 c
->v
.v1
.throttling
= 0;
4478 c
->type
= CHAN_AGENT
; /* identify channel type */
4479 c
->u
.a
.lensofar
= 0;
4480 add234(ssh
->channels
, c
);
4481 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4482 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
4487 static void ssh1_msg_port_open(Ssh ssh
, struct Packet
*pktin
)
4489 /* Remote side is trying to open a channel to talk to a
4490 * forwarded port. Give them back a local channel number. */
4491 struct ssh_channel
*c
;
4492 struct ssh_rportfwd pf
, *pfp
;
4497 c
= snew(struct ssh_channel
);
4500 remoteid
= ssh_pkt_getuint32(pktin
);
4501 ssh_pkt_getstring(pktin
, &host
, &hostsize
);
4502 port
= ssh_pkt_getuint32(pktin
);
4504 if (hostsize
>= lenof(pf
.dhost
))
4505 hostsize
= lenof(pf
.dhost
)-1;
4506 memcpy(pf
.dhost
, host
, hostsize
);
4507 pf
.dhost
[hostsize
] = '\0';
4509 pfp
= find234(ssh
->rportfwds
, &pf
, NULL
);
4512 logeventf(ssh
, "Rejected remote port open request for %s:%d",
4514 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4515 PKT_INT
, remoteid
, PKT_END
);
4517 logeventf(ssh
, "Received remote port open request for %s:%d",
4519 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
4520 c
, &ssh
->cfg
, pfp
->pfrec
->addressfamily
);
4522 logeventf(ssh
, "Port open failed: %s", e
);
4524 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4525 PKT_INT
, remoteid
, PKT_END
);
4527 c
->remoteid
= remoteid
;
4528 c
->halfopen
= FALSE
;
4529 c
->localid
= alloc_channel_id(ssh
);
4531 c
->v
.v1
.throttling
= 0;
4532 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
4533 add234(ssh
->channels
, c
);
4534 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4535 PKT_INT
, c
->remoteid
, PKT_INT
,
4536 c
->localid
, PKT_END
);
4537 logevent("Forwarded port opened successfully");
4542 static void ssh1_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
4544 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4545 unsigned int localid
= ssh_pkt_getuint32(pktin
);
4546 struct ssh_channel
*c
;
4548 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4549 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4550 c
->remoteid
= localid
;
4551 c
->halfopen
= FALSE
;
4552 c
->type
= CHAN_SOCKDATA
;
4553 c
->v
.v1
.throttling
= 0;
4554 pfd_confirm(c
->u
.pfd
.s
);
4557 if (c
&& c
->closes
) {
4559 * We have a pending close on this channel,
4560 * which we decided on before the server acked
4561 * the channel open. So now we know the
4562 * remoteid, we can close it again.
4564 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
4565 PKT_INT
, c
->remoteid
, PKT_END
);
4569 static void ssh1_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
4571 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4572 struct ssh_channel
*c
;
4574 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4575 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4576 logevent("Forwarded connection refused by server");
4577 pfd_close(c
->u
.pfd
.s
);
4578 del234(ssh
->channels
, c
);
4583 static void ssh1_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
4585 /* Remote side closes a channel. */
4586 unsigned i
= ssh_pkt_getuint32(pktin
);
4587 struct ssh_channel
*c
;
4588 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4589 if (c
&& !c
->halfopen
) {
4592 (pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
4594 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
4595 logevent("Forwarded X11 connection terminated");
4596 assert(c
->u
.x11
.s
!= NULL
);
4597 x11_close(c
->u
.x11
.s
);
4600 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
4601 logevent("Forwarded port closed");
4602 assert(c
->u
.pfd
.s
!= NULL
);
4603 pfd_close(c
->u
.pfd
.s
);
4607 c
->closes
|= (closetype
<< 2); /* seen this message */
4608 if (!(c
->closes
& closetype
)) {
4609 send_packet(ssh
, pktin
->type
, PKT_INT
, c
->remoteid
,
4611 c
->closes
|= closetype
; /* sent it too */
4614 if (c
->closes
== 15) {
4615 del234(ssh
->channels
, c
);
4619 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4620 pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
4621 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
4626 static void ssh1_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
4628 /* Data sent down one of our channels. */
4629 int i
= ssh_pkt_getuint32(pktin
);
4632 struct ssh_channel
*c
;
4634 ssh_pkt_getstring(pktin
, &p
, &len
);
4636 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4641 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
4644 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
4647 /* Data for an agent message. Buffer it. */
4649 if (c
->u
.a
.lensofar
< 4) {
4650 unsigned int l
= min(4 - c
->u
.a
.lensofar
, (unsigned)len
);
4651 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
4655 c
->u
.a
.lensofar
+= l
;
4657 if (c
->u
.a
.lensofar
== 4) {
4659 4 + GET_32BIT(c
->u
.a
.msglen
);
4660 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
4662 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
4664 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
4666 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
4668 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
4672 c
->u
.a
.lensofar
+= l
;
4674 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
4677 if (agent_query(c
->u
.a
.message
,
4680 ssh_agentf_callback
, c
))
4681 ssh_agentf_callback(c
, reply
, replylen
);
4682 sfree(c
->u
.a
.message
);
4683 c
->u
.a
.lensofar
= 0;
4686 bufsize
= 0; /* agent channels never back up */
4689 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4690 c
->v
.v1
.throttling
= 1;
4691 ssh1_throttle(ssh
, +1);
4696 static void ssh1_smsg_exit_status(Ssh ssh
, struct Packet
*pktin
)
4698 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
4699 logeventf(ssh
, "Server sent command exit status %d", ssh
->exitcode
);
4700 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
4702 * In case `helpful' firewalls or proxies tack
4703 * extra human-readable text on the end of the
4704 * session which we might mistake for another
4705 * encrypted packet, we close the session once
4706 * we've sent EXIT_CONFIRMATION.
4708 ssh_disconnect(ssh
, NULL
, NULL
, 0, TRUE
);
4711 /* Helper function to deal with sending tty modes for REQUEST_PTY */
4712 static void ssh1_send_ttymode(void *data
, char *mode
, char *val
)
4714 struct Packet
*pktout
= (struct Packet
*)data
;
4716 unsigned int arg
= 0;
4717 while (strcmp(mode
, ssh_ttymodes
[i
].mode
) != 0) i
++;
4718 if (i
== lenof(ssh_ttymodes
)) return;
4719 switch (ssh_ttymodes
[i
].type
) {
4721 arg
= ssh_tty_parse_specchar(val
);
4724 arg
= ssh_tty_parse_boolean(val
);
4727 ssh2_pkt_addbyte(pktout
, ssh_ttymodes
[i
].opcode
);
4728 ssh2_pkt_addbyte(pktout
, arg
);
4732 static void do_ssh1_connection(Ssh ssh
, unsigned char *in
, int inlen
,
4733 struct Packet
*pktin
)
4735 crBegin(ssh
->do_ssh1_connection_crstate
);
4737 ssh
->packet_dispatch
[SSH1_SMSG_STDOUT_DATA
] =
4738 ssh
->packet_dispatch
[SSH1_SMSG_STDERR_DATA
] =
4739 ssh1_smsg_stdout_stderr_data
;
4741 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
] =
4742 ssh1_msg_channel_open_confirmation
;
4743 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_FAILURE
] =
4744 ssh1_msg_channel_open_failure
;
4745 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE
] =
4746 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
] =
4747 ssh1_msg_channel_close
;
4748 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_DATA
] = ssh1_msg_channel_data
;
4749 ssh
->packet_dispatch
[SSH1_SMSG_EXIT_STATUS
] = ssh1_smsg_exit_status
;
4751 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
4752 logevent("Requesting agent forwarding");
4753 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
4757 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4758 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4759 bombout(("Protocol confusion"));
4761 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4762 logevent("Agent forwarding refused");
4764 logevent("Agent forwarding enabled");
4765 ssh
->agentfwd_enabled
= TRUE
;
4766 ssh
->packet_dispatch
[SSH1_SMSG_AGENT_OPEN
] = ssh1_smsg_agent_open
;
4770 if (ssh
->cfg
.x11_forward
) {
4771 char proto
[20], data
[64];
4772 logevent("Requesting X11 forwarding");
4773 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
4774 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
4775 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
4777 * Note that while we blank the X authentication data here, we don't
4778 * take any special action to blank the start of an X11 channel,
4779 * so using MIT-MAGIC-COOKIE-1 and actually opening an X connection
4780 * without having session blanking enabled is likely to leak your
4781 * cookie into the log.
4783 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
4784 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4786 PKTT_PASSWORD
, PKT_STR
, data
, PKTT_OTHER
,
4787 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
4790 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4792 PKTT_PASSWORD
, PKT_STR
, data
, PKTT_OTHER
, PKT_END
);
4797 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4798 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4799 bombout(("Protocol confusion"));
4801 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4802 logevent("X11 forwarding refused");
4804 logevent("X11 forwarding enabled");
4805 ssh
->X11_fwd_enabled
= TRUE
;
4806 ssh
->packet_dispatch
[SSH1_SMSG_X11_OPEN
] = ssh1_smsg_x11_open
;
4810 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
4811 ssh
->packet_dispatch
[SSH1_MSG_PORT_OPEN
] = ssh1_msg_port_open
;
4813 if (!ssh
->cfg
.nopty
) {
4815 /* Unpick the terminal-speed string. */
4816 /* XXX perhaps we should allow no speeds to be sent. */
4817 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
4818 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
4819 /* Send the pty request. */
4820 pkt
= ssh1_pkt_init(SSH1_CMSG_REQUEST_PTY
);
4821 ssh_pkt_addstring(pkt
, ssh
->cfg
.termtype
);
4822 ssh_pkt_adduint32(pkt
, ssh
->term_height
);
4823 ssh_pkt_adduint32(pkt
, ssh
->term_width
);
4824 ssh_pkt_adduint32(pkt
, 0); /* width in pixels */
4825 ssh_pkt_adduint32(pkt
, 0); /* height in pixels */
4826 parse_ttymodes(ssh
, ssh
->cfg
.ttymodes
,
4827 ssh1_send_ttymode
, (void *)pkt
);
4828 ssh_pkt_addbyte(pkt
, SSH1_TTY_OP_ISPEED
);
4829 ssh_pkt_adduint32(pkt
, ssh
->ispeed
);
4830 ssh_pkt_addbyte(pkt
, SSH1_TTY_OP_OSPEED
);
4831 ssh_pkt_adduint32(pkt
, ssh
->ospeed
);
4832 ssh_pkt_addbyte(pkt
, SSH_TTY_OP_END
);
4834 ssh
->state
= SSH_STATE_INTERMED
;
4838 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4839 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4840 bombout(("Protocol confusion"));
4842 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4843 c_write_str(ssh
, "Server refused to allocate pty\r\n");
4844 ssh
->editing
= ssh
->echoing
= 1;
4846 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
4847 ssh
->ospeed
, ssh
->ispeed
);
4849 ssh
->editing
= ssh
->echoing
= 1;
4852 if (ssh
->cfg
.compression
) {
4853 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
4857 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4858 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4859 bombout(("Protocol confusion"));
4861 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4862 c_write_str(ssh
, "Server refused to compress\r\n");
4864 logevent("Started compression");
4865 ssh
->v1_compressing
= TRUE
;
4866 ssh
->cs_comp_ctx
= zlib_compress_init();
4867 logevent("Initialised zlib (RFC1950) compression");
4868 ssh
->sc_comp_ctx
= zlib_decompress_init();
4869 logevent("Initialised zlib (RFC1950) decompression");
4873 * Start the shell or command.
4875 * Special case: if the first-choice command is an SSH-2
4876 * subsystem (hence not usable here) and the second choice
4877 * exists, we fall straight back to that.
4880 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
4882 if (!cmd
) cmd
= ssh
->cfg
.remote_cmd
;
4884 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
4885 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
4886 ssh
->fallback_cmd
= TRUE
;
4889 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
4891 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
4892 logevent("Started session");
4895 ssh
->state
= SSH_STATE_SESSION
;
4896 if (ssh
->size_needed
)
4897 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
4898 if (ssh
->eof_needed
)
4899 ssh_special(ssh
, TS_EOF
);
4902 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
4904 ssh
->channels
= newtree234(ssh_channelcmp
);
4908 * By this point, most incoming packets are already being
4909 * handled by the dispatch table, and we need only pay
4910 * attention to the unusual ones.
4915 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
4916 /* may be from EXEC_SHELL on some servers */
4917 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4918 /* may be from EXEC_SHELL on some servers
4919 * if no pty is available or in other odd cases. Ignore */
4921 bombout(("Strange packet received: type %d", pktin
->type
));
4926 int len
= min(inlen
, 512);
4927 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4928 PKT_INT
, len
, PKT_DATA
, in
, len
,
4929 PKTT_OTHER
, PKT_END
);
4940 * Handle the top-level SSH-2 protocol.
4942 static void ssh1_msg_debug(Ssh ssh
, struct Packet
*pktin
)
4947 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4948 logeventf(ssh
, "Remote debug message: %.*s", msglen
, msg
);
4951 static void ssh1_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
4953 /* log reason code in disconnect message */
4957 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4958 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen
, msg
));
4961 static void ssh_msg_ignore(Ssh ssh
, struct Packet
*pktin
)
4963 /* Do nothing, because we're ignoring it! Duhh. */
4966 static void ssh1_protocol_setup(Ssh ssh
)
4971 * Most messages are handled by the coroutines.
4973 for (i
= 0; i
< 256; i
++)
4974 ssh
->packet_dispatch
[i
] = NULL
;
4977 * These special message types we install handlers for.
4979 ssh
->packet_dispatch
[SSH1_MSG_DISCONNECT
] = ssh1_msg_disconnect
;
4980 ssh
->packet_dispatch
[SSH1_MSG_IGNORE
] = ssh_msg_ignore
;
4981 ssh
->packet_dispatch
[SSH1_MSG_DEBUG
] = ssh1_msg_debug
;
4984 static void ssh1_protocol(Ssh ssh
, void *vin
, int inlen
,
4985 struct Packet
*pktin
)
4987 unsigned char *in
=(unsigned char*)vin
;
4988 if (ssh
->state
== SSH_STATE_CLOSED
)
4991 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
4992 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
4996 if (!ssh
->protocol_initial_phase_done
) {
4997 if (do_ssh1_login(ssh
, in
, inlen
, pktin
))
4998 ssh
->protocol_initial_phase_done
= TRUE
;
5003 do_ssh1_connection(ssh
, in
, inlen
, pktin
);
5007 * Utility routine for decoding comma-separated strings in KEXINIT.
5009 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
5012 if (!needle
|| !haystack
) /* protect against null pointers */
5014 needlen
= strlen(needle
);
5017 * Is it at the start of the string?
5019 if (haylen
>= needlen
&& /* haystack is long enough */
5020 !memcmp(needle
, haystack
, needlen
) && /* initial match */
5021 (haylen
== needlen
|| haystack
[needlen
] == ',')
5022 /* either , or EOS follows */
5026 * If not, search for the next comma and resume after that.
5027 * If no comma found, terminate.
5029 while (haylen
> 0 && *haystack
!= ',')
5030 haylen
--, haystack
++;
5033 haylen
--, haystack
++; /* skip over comma itself */
5038 * Similar routine for checking whether we have the first string in a list.
5040 static int first_in_commasep_string(char *needle
, char *haystack
, int haylen
)
5043 if (!needle
|| !haystack
) /* protect against null pointers */
5045 needlen
= strlen(needle
);
5047 * Is it at the start of the string?
5049 if (haylen
>= needlen
&& /* haystack is long enough */
5050 !memcmp(needle
, haystack
, needlen
) && /* initial match */
5051 (haylen
== needlen
|| haystack
[needlen
] == ',')
5052 /* either , or EOS follows */
5060 * SSH-2 key creation method.
5061 * (Currently assumes 2 lots of any hash are sufficient to generate
5062 * keys/IVs for any cipher/MAC. SSH2_MKKEY_ITERS documents this assumption.)
5064 #define SSH2_MKKEY_ITERS (2)
5065 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
, char chr
,
5066 unsigned char *keyspace
)
5068 const struct ssh_hash
*h
= ssh
->kex
->hash
;
5070 /* First hlen bytes. */
5072 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
5073 hash_mpint(h
, s
, K
);
5074 h
->bytes(s
, H
, h
->hlen
);
5075 h
->bytes(s
, &chr
, 1);
5076 h
->bytes(s
, ssh
->v2_session_id
, ssh
->v2_session_id_len
);
5077 h
->final(s
, keyspace
);
5078 /* Next hlen bytes. */
5080 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
5081 hash_mpint(h
, s
, K
);
5082 h
->bytes(s
, H
, h
->hlen
);
5083 h
->bytes(s
, keyspace
, h
->hlen
);
5084 h
->final(s
, keyspace
+ h
->hlen
);
5088 * Handle the SSH-2 transport layer.
5090 static int do_ssh2_transport(Ssh ssh
, void *vin
, int inlen
,
5091 struct Packet
*pktin
)
5093 unsigned char *in
= (unsigned char *)vin
;
5094 struct do_ssh2_transport_state
{
5095 int nbits
, pbits
, warn_kex
, warn_cscipher
, warn_sccipher
;
5096 Bignum p
, g
, e
, f
, K
;
5099 int kex_init_value
, kex_reply_value
;
5100 const struct ssh_mac
**maclist
;
5102 const struct ssh2_cipher
*cscipher_tobe
;
5103 const struct ssh2_cipher
*sccipher_tobe
;
5104 const struct ssh_mac
*csmac_tobe
;
5105 const struct ssh_mac
*scmac_tobe
;
5106 const struct ssh_compress
*cscomp_tobe
;
5107 const struct ssh_compress
*sccomp_tobe
;
5108 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
5109 int hostkeylen
, siglen
;
5110 void *hkey
; /* actual host key */
5111 unsigned char exchange_hash
[SSH2_KEX_MAX_HASH_LEN
];
5112 int n_preferred_kex
;
5113 const struct ssh_kexes
*preferred_kex
[KEX_MAX
];
5114 int n_preferred_ciphers
;
5115 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
5116 const struct ssh_compress
*preferred_comp
;
5117 int got_session_id
, activated_authconn
;
5118 struct Packet
*pktout
;
5123 crState(do_ssh2_transport_state
);
5125 crBegin(ssh
->do_ssh2_transport_crstate
);
5127 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
5128 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
5129 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
5131 s
->got_session_id
= s
->activated_authconn
= FALSE
;
5134 * Be prepared to work around the buggy MAC problem.
5136 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
5137 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
5139 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
5142 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_KEX_MASK
;
5144 int i
, j
, commalist_started
;
5147 * Set up the preferred key exchange. (NULL => warn below here)
5149 s
->n_preferred_kex
= 0;
5150 for (i
= 0; i
< KEX_MAX
; i
++) {
5151 switch (ssh
->cfg
.ssh_kexlist
[i
]) {
5153 s
->preferred_kex
[s
->n_preferred_kex
++] =
5154 &ssh_diffiehellman_gex
;
5157 s
->preferred_kex
[s
->n_preferred_kex
++] =
5158 &ssh_diffiehellman_group14
;
5161 s
->preferred_kex
[s
->n_preferred_kex
++] =
5162 &ssh_diffiehellman_group1
;
5165 /* Flag for later. Don't bother if it's the last in
5167 if (i
< KEX_MAX
- 1) {
5168 s
->preferred_kex
[s
->n_preferred_kex
++] = NULL
;
5175 * Set up the preferred ciphers. (NULL => warn below here)
5177 s
->n_preferred_ciphers
= 0;
5178 for (i
= 0; i
< CIPHER_MAX
; i
++) {
5179 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
5180 case CIPHER_BLOWFISH
:
5181 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
5184 if (ssh
->cfg
.ssh2_des_cbc
) {
5185 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
5189 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
5192 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
5194 case CIPHER_ARCFOUR
:
5195 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_arcfour
;
5198 /* Flag for later. Don't bother if it's the last in
5200 if (i
< CIPHER_MAX
- 1) {
5201 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
5208 * Set up preferred compression.
5210 if (ssh
->cfg
.compression
)
5211 s
->preferred_comp
= &ssh_zlib
;
5213 s
->preferred_comp
= &ssh_comp_none
;
5216 * Enable queueing of outgoing auth- or connection-layer
5217 * packets while we are in the middle of a key exchange.
5219 ssh
->queueing
= TRUE
;
5222 * Flag that KEX is in progress.
5224 ssh
->kex_in_progress
= TRUE
;
5227 * Construct and send our key exchange packet.
5229 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEXINIT
);
5230 for (i
= 0; i
< 16; i
++)
5231 ssh2_pkt_addbyte(s
->pktout
, (unsigned char) random_byte());
5232 /* List key exchange algorithms. */
5233 ssh2_pkt_addstring_start(s
->pktout
);
5234 commalist_started
= 0;
5235 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
5236 const struct ssh_kexes
*k
= s
->preferred_kex
[i
];
5237 if (!k
) continue; /* warning flag */
5238 for (j
= 0; j
< k
->nkexes
; j
++) {
5239 if (commalist_started
)
5240 ssh2_pkt_addstring_str(s
->pktout
, ",");
5241 ssh2_pkt_addstring_str(s
->pktout
, k
->list
[j
]->name
);
5242 commalist_started
= 1;
5245 /* List server host key algorithms. */
5246 ssh2_pkt_addstring_start(s
->pktout
);
5247 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
5248 ssh2_pkt_addstring_str(s
->pktout
, hostkey_algs
[i
]->name
);
5249 if (i
< lenof(hostkey_algs
) - 1)
5250 ssh2_pkt_addstring_str(s
->pktout
, ",");
5252 /* List client->server encryption algorithms. */
5253 ssh2_pkt_addstring_start(s
->pktout
);
5254 commalist_started
= 0;
5255 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5256 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5257 if (!c
) continue; /* warning flag */
5258 for (j
= 0; j
< c
->nciphers
; j
++) {
5259 if (commalist_started
)
5260 ssh2_pkt_addstring_str(s
->pktout
, ",");
5261 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
5262 commalist_started
= 1;
5265 /* List server->client encryption algorithms. */
5266 ssh2_pkt_addstring_start(s
->pktout
);
5267 commalist_started
= 0;
5268 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5269 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5270 if (!c
) continue; /* warning flag */
5271 for (j
= 0; j
< c
->nciphers
; j
++) {
5272 if (commalist_started
)
5273 ssh2_pkt_addstring_str(s
->pktout
, ",");
5274 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
5275 commalist_started
= 1;
5278 /* List client->server MAC algorithms. */
5279 ssh2_pkt_addstring_start(s
->pktout
);
5280 for (i
= 0; i
< s
->nmacs
; i
++) {
5281 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
5282 if (i
< s
->nmacs
- 1)
5283 ssh2_pkt_addstring_str(s
->pktout
, ",");
5285 /* List server->client MAC algorithms. */
5286 ssh2_pkt_addstring_start(s
->pktout
);
5287 for (i
= 0; i
< s
->nmacs
; i
++) {
5288 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
5289 if (i
< s
->nmacs
- 1)
5290 ssh2_pkt_addstring_str(s
->pktout
, ",");
5292 /* List client->server compression algorithms. */
5293 ssh2_pkt_addstring_start(s
->pktout
);
5294 assert(lenof(compressions
) > 1);
5295 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
5296 for (i
= 0; i
< lenof(compressions
); i
++) {
5297 const struct ssh_compress
*c
= compressions
[i
];
5298 if (c
!= s
->preferred_comp
) {
5299 ssh2_pkt_addstring_str(s
->pktout
, ",");
5300 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
5303 /* List server->client compression algorithms. */
5304 ssh2_pkt_addstring_start(s
->pktout
);
5305 assert(lenof(compressions
) > 1);
5306 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
5307 for (i
= 0; i
< lenof(compressions
); i
++) {
5308 const struct ssh_compress
*c
= compressions
[i
];
5309 if (c
!= s
->preferred_comp
) {
5310 ssh2_pkt_addstring_str(s
->pktout
, ",");
5311 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
5314 /* List client->server languages. Empty list. */
5315 ssh2_pkt_addstring_start(s
->pktout
);
5316 /* List server->client languages. Empty list. */
5317 ssh2_pkt_addstring_start(s
->pktout
);
5318 /* First KEX packet does _not_ follow, because we're not that brave. */
5319 ssh2_pkt_addbool(s
->pktout
, FALSE
);
5321 ssh2_pkt_adduint32(s
->pktout
, 0);
5324 s
->our_kexinitlen
= s
->pktout
->length
- 5;
5325 s
->our_kexinit
= snewn(s
->our_kexinitlen
, unsigned char);
5326 memcpy(s
->our_kexinit
, s
->pktout
->data
+ 5, s
->our_kexinitlen
);
5328 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5334 * Now examine the other side's KEXINIT to see what we're up
5338 char *str
, *preferred
;
5341 if (pktin
->type
!= SSH2_MSG_KEXINIT
) {
5342 bombout(("expected key exchange packet from server"));
5346 ssh
->hostkey
= NULL
;
5347 s
->cscipher_tobe
= NULL
;
5348 s
->sccipher_tobe
= NULL
;
5349 s
->csmac_tobe
= NULL
;
5350 s
->scmac_tobe
= NULL
;
5351 s
->cscomp_tobe
= NULL
;
5352 s
->sccomp_tobe
= NULL
;
5353 s
->warn_kex
= s
->warn_cscipher
= s
->warn_sccipher
= FALSE
;
5355 pktin
->savedpos
+= 16; /* skip garbage cookie */
5356 ssh_pkt_getstring(pktin
, &str
, &len
); /* key exchange algorithms */
5359 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
5360 const struct ssh_kexes
*k
= s
->preferred_kex
[i
];
5364 for (j
= 0; j
< k
->nkexes
; j
++) {
5365 if (!preferred
) preferred
= k
->list
[j
]->name
;
5366 if (in_commasep_string(k
->list
[j
]->name
, str
, len
)) {
5367 ssh
->kex
= k
->list
[j
];
5376 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
5377 str ? str
: "(null)"));
5381 * Note that the server's guess is considered wrong if it doesn't match
5382 * the first algorithm in our list, even if it's still the algorithm
5385 s
->guessok
= first_in_commasep_string(preferred
, str
, len
);
5386 ssh_pkt_getstring(pktin
, &str
, &len
); /* host key algorithms */
5387 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
5388 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
5389 ssh
->hostkey
= hostkey_algs
[i
];
5393 s
->guessok
= s
->guessok
&&
5394 first_in_commasep_string(hostkey_algs
[0]->name
, str
, len
);
5395 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server cipher */
5396 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5397 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5399 s
->warn_cscipher
= TRUE
;
5401 for (j
= 0; j
< c
->nciphers
; j
++) {
5402 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
5403 s
->cscipher_tobe
= c
->list
[j
];
5408 if (s
->cscipher_tobe
)
5411 if (!s
->cscipher_tobe
) {
5412 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
5413 str ? str
: "(null)"));
5417 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client cipher */
5418 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5419 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5421 s
->warn_sccipher
= TRUE
;
5423 for (j
= 0; j
< c
->nciphers
; j
++) {
5424 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
5425 s
->sccipher_tobe
= c
->list
[j
];
5430 if (s
->sccipher_tobe
)
5433 if (!s
->sccipher_tobe
) {
5434 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
5435 str ? str
: "(null)"));
5439 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server mac */
5440 for (i
= 0; i
< s
->nmacs
; i
++) {
5441 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5442 s
->csmac_tobe
= s
->maclist
[i
];
5446 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client mac */
5447 for (i
= 0; i
< s
->nmacs
; i
++) {
5448 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5449 s
->scmac_tobe
= s
->maclist
[i
];
5453 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server compression */
5454 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5455 const struct ssh_compress
*c
=
5456 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5457 if (in_commasep_string(c
->name
, str
, len
)) {
5462 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client compression */
5463 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5464 const struct ssh_compress
*c
=
5465 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5466 if (in_commasep_string(c
->name
, str
, len
)) {
5471 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server language */
5472 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client language */
5473 s
->ignorepkt
= ssh2_pkt_getbool(pktin
) && !s
->guessok
;
5476 ssh_set_frozen(ssh
, 1);
5477 s
->dlgret
= askalg(ssh
->frontend
, "key-exchange algorithm",
5479 ssh_dialog_callback
, ssh
);
5480 if (s
->dlgret
< 0) {
5484 bombout(("Unexpected data from server while"
5485 " waiting for user response"));
5488 } while (pktin
|| inlen
> 0);
5489 s
->dlgret
= ssh
->user_response
;
5491 ssh_set_frozen(ssh
, 0);
5492 if (s
->dlgret
== 0) {
5493 ssh_disconnect(ssh
, "User aborted at kex warning", NULL
,
5499 if (s
->warn_cscipher
) {
5500 ssh_set_frozen(ssh
, 1);
5501 s
->dlgret
= askalg(ssh
->frontend
,
5502 "client-to-server cipher",
5503 s
->cscipher_tobe
->name
,
5504 ssh_dialog_callback
, ssh
);
5505 if (s
->dlgret
< 0) {
5509 bombout(("Unexpected data from server while"
5510 " waiting for user response"));
5513 } while (pktin
|| inlen
> 0);
5514 s
->dlgret
= ssh
->user_response
;
5516 ssh_set_frozen(ssh
, 0);
5517 if (s
->dlgret
== 0) {
5518 ssh_disconnect(ssh
, "User aborted at cipher warning", NULL
,
5524 if (s
->warn_sccipher
) {
5525 ssh_set_frozen(ssh
, 1);
5526 s
->dlgret
= askalg(ssh
->frontend
,
5527 "server-to-client cipher",
5528 s
->sccipher_tobe
->name
,
5529 ssh_dialog_callback
, ssh
);
5530 if (s
->dlgret
< 0) {
5534 bombout(("Unexpected data from server while"
5535 " waiting for user response"));
5538 } while (pktin
|| inlen
> 0);
5539 s
->dlgret
= ssh
->user_response
;
5541 ssh_set_frozen(ssh
, 0);
5542 if (s
->dlgret
== 0) {
5543 ssh_disconnect(ssh
, "User aborted at cipher warning", NULL
,
5549 ssh
->exhash
= ssh
->kex
->hash
->init();
5550 hash_string(ssh
->kex
->hash
, ssh
->exhash
, ssh
->v_c
, strlen(ssh
->v_c
));
5551 hash_string(ssh
->kex
->hash
, ssh
->exhash
, ssh
->v_s
, strlen(ssh
->v_s
));
5552 hash_string(ssh
->kex
->hash
, ssh
->exhash
,
5553 s
->our_kexinit
, s
->our_kexinitlen
);
5554 sfree(s
->our_kexinit
);
5555 if (pktin
->length
> 5)
5556 hash_string(ssh
->kex
->hash
, ssh
->exhash
,
5557 pktin
->data
+ 5, pktin
->length
- 5);
5559 if (s
->ignorepkt
) /* first_kex_packet_follows */
5560 crWaitUntil(pktin
); /* Ignore packet */
5564 * Work out the number of bits of key we will need from the key
5565 * exchange. We start with the maximum key length of either
5571 csbits
= s
->cscipher_tobe
->keylen
;
5572 scbits
= s
->sccipher_tobe
->keylen
;
5573 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
5575 /* The keys only have hlen-bit entropy, since they're based on
5576 * a hash. So cap the key size at hlen bits. */
5577 if (s
->nbits
> ssh
->kex
->hash
->hlen
* 8)
5578 s
->nbits
= ssh
->kex
->hash
->hlen
* 8;
5581 * If we're doing Diffie-Hellman group exchange, start by
5582 * requesting a group.
5584 if (!ssh
->kex
->pdata
) {
5585 logevent("Doing Diffie-Hellman group exchange");
5586 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
5588 * Work out how big a DH group we will need to allow that
5591 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
5592 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
5593 ssh2_pkt_adduint32(s
->pktout
, s
->pbits
);
5594 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5597 if (pktin
->type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
5598 bombout(("expected key exchange group packet from server"));
5601 s
->p
= ssh2_pkt_getmp(pktin
);
5602 s
->g
= ssh2_pkt_getmp(pktin
);
5603 if (!s
->p
|| !s
->g
) {
5604 bombout(("unable to read mp-ints from incoming group packet"));
5607 ssh
->kex_ctx
= dh_setup_gex(s
->p
, s
->g
);
5608 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
5609 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
5611 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP
;
5612 ssh
->kex_ctx
= dh_setup_group(ssh
->kex
);
5613 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
5614 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
5615 logeventf(ssh
, "Using Diffie-Hellman with standard group \"%s\"",
5616 ssh
->kex
->groupname
);
5619 logeventf(ssh
, "Doing Diffie-Hellman key exchange with hash %s",
5620 ssh
->kex
->hash
->text_name
);
5622 * Now generate and send e for Diffie-Hellman.
5624 set_busy_status(ssh
->frontend
, BUSY_CPU
); /* this can take a while */
5625 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
5626 s
->pktout
= ssh2_pkt_init(s
->kex_init_value
);
5627 ssh2_pkt_addmp(s
->pktout
, s
->e
);
5628 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5630 set_busy_status(ssh
->frontend
, BUSY_WAITING
); /* wait for server */
5632 if (pktin
->type
!= s
->kex_reply_value
) {
5633 bombout(("expected key exchange reply packet from server"));
5636 set_busy_status(ssh
->frontend
, BUSY_CPU
); /* cogitate */
5637 ssh_pkt_getstring(pktin
, &s
->hostkeydata
, &s
->hostkeylen
);
5638 s
->f
= ssh2_pkt_getmp(pktin
);
5640 bombout(("unable to parse key exchange reply packet"));
5643 ssh_pkt_getstring(pktin
, &s
->sigdata
, &s
->siglen
);
5645 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
5647 /* We assume everything from now on will be quick, and it might
5648 * involve user interaction. */
5649 set_busy_status(ssh
->frontend
, BUSY_NOT
);
5651 hash_string(ssh
->kex
->hash
, ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
5652 if (!ssh
->kex
->pdata
) {
5653 hash_uint32(ssh
->kex
->hash
, ssh
->exhash
, s
->pbits
);
5654 hash_mpint(ssh
->kex
->hash
, ssh
->exhash
, s
->p
);
5655 hash_mpint(ssh
->kex
->hash
, ssh
->exhash
, s
->g
);
5657 hash_mpint(ssh
->kex
->hash
, ssh
->exhash
, s
->e
);
5658 hash_mpint(ssh
->kex
->hash
, ssh
->exhash
, s
->f
);
5659 hash_mpint(ssh
->kex
->hash
, ssh
->exhash
, s
->K
);
5660 assert(ssh
->kex
->hash
->hlen
<= sizeof(s
->exchange_hash
));
5661 ssh
->kex
->hash
->final(ssh
->exhash
, s
->exchange_hash
);
5663 dh_cleanup(ssh
->kex_ctx
);
5664 ssh
->kex_ctx
= NULL
;
5667 debug(("Exchange hash is:\n"));
5668 dmemdump(s
->exchange_hash
, ssh
->kex
->hash
->hlen
);
5671 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
5673 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
5674 (char *)s
->exchange_hash
,
5675 ssh
->kex
->hash
->hlen
)) {
5676 bombout(("Server's host key did not match the signature supplied"));
5681 * Authenticate remote host: verify host key. (We've already
5682 * checked the signature of the exchange hash.)
5684 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
5685 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
5686 ssh_set_frozen(ssh
, 1);
5687 s
->dlgret
= verify_ssh_host_key(ssh
->frontend
,
5688 ssh
->savedhost
, ssh
->savedport
,
5689 ssh
->hostkey
->keytype
, s
->keystr
,
5691 ssh_dialog_callback
, ssh
);
5692 if (s
->dlgret
< 0) {
5696 bombout(("Unexpected data from server while waiting"
5697 " for user host key response"));
5700 } while (pktin
|| inlen
> 0);
5701 s
->dlgret
= ssh
->user_response
;
5703 ssh_set_frozen(ssh
, 0);
5704 if (s
->dlgret
== 0) {
5705 ssh_disconnect(ssh
, "User aborted at host key verification", NULL
,
5709 if (!s
->got_session_id
) { /* don't bother logging this in rekeys */
5710 logevent("Host key fingerprint is:");
5711 logevent(s
->fingerprint
);
5713 sfree(s
->fingerprint
);
5715 ssh
->hostkey
->freekey(s
->hkey
);
5718 * The exchange hash from the very first key exchange is also
5719 * the session id, used in session key construction and
5722 if (!s
->got_session_id
) {
5723 assert(sizeof(s
->exchange_hash
) <= sizeof(ssh
->v2_session_id
));
5724 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
5725 sizeof(s
->exchange_hash
));
5726 ssh
->v2_session_id_len
= ssh
->kex
->hash
->hlen
;
5727 assert(ssh
->v2_session_id_len
<= sizeof(ssh
->v2_session_id
));
5728 s
->got_session_id
= TRUE
;
5732 * Send SSH2_MSG_NEWKEYS.
5734 s
->pktout
= ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
5735 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5736 ssh
->outgoing_data_size
= 0; /* start counting from here */
5739 * We've sent client NEWKEYS, so create and initialise
5740 * client-to-server session keys.
5742 if (ssh
->cs_cipher_ctx
)
5743 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
5744 ssh
->cscipher
= s
->cscipher_tobe
;
5745 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
5747 if (ssh
->cs_mac_ctx
)
5748 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
5749 ssh
->csmac
= s
->csmac_tobe
;
5750 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
5752 if (ssh
->cs_comp_ctx
)
5753 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
5754 ssh
->cscomp
= s
->cscomp_tobe
;
5755 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
5758 * Set IVs on client-to-server keys. Here we use the exchange
5759 * hash from the _first_ key exchange.
5762 unsigned char keyspace
[SSH2_KEX_MAX_HASH_LEN
* SSH2_MKKEY_ITERS
];
5763 assert(sizeof(keyspace
) >= ssh
->kex
->hash
->hlen
* SSH2_MKKEY_ITERS
);
5764 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,'C',keyspace
);
5765 assert((ssh
->cscipher
->keylen
+7) / 8 <=
5766 ssh
->kex
->hash
->hlen
* SSH2_MKKEY_ITERS
);
5767 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
5768 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,'A',keyspace
);
5769 assert(ssh
->cscipher
->blksize
<=
5770 ssh
->kex
->hash
->hlen
* SSH2_MKKEY_ITERS
);
5771 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
5772 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,'E',keyspace
);
5773 assert(ssh
->csmac
->len
<=
5774 ssh
->kex
->hash
->hlen
* SSH2_MKKEY_ITERS
);
5775 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
5776 memset(keyspace
, 0, sizeof(keyspace
));
5779 logeventf(ssh
, "Initialised %.200s client->server encryption",
5780 ssh
->cscipher
->text_name
);
5781 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
5782 ssh
->csmac
->text_name
);
5783 if (ssh
->cscomp
->text_name
)
5784 logeventf(ssh
, "Initialised %s compression",
5785 ssh
->cscomp
->text_name
);
5788 * Now our end of the key exchange is complete, we can send all
5789 * our queued higher-layer packets.
5791 ssh
->queueing
= FALSE
;
5792 ssh2_pkt_queuesend(ssh
);
5795 * Expect SSH2_MSG_NEWKEYS from server.
5798 if (pktin
->type
!= SSH2_MSG_NEWKEYS
) {
5799 bombout(("expected new-keys packet from server"));
5802 ssh
->incoming_data_size
= 0; /* start counting from here */
5805 * We've seen server NEWKEYS, so create and initialise
5806 * server-to-client session keys.
5808 if (ssh
->sc_cipher_ctx
)
5809 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
5810 ssh
->sccipher
= s
->sccipher_tobe
;
5811 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
5813 if (ssh
->sc_mac_ctx
)
5814 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
5815 ssh
->scmac
= s
->scmac_tobe
;
5816 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
5818 if (ssh
->sc_comp_ctx
)
5819 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
5820 ssh
->sccomp
= s
->sccomp_tobe
;
5821 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
5824 * Set IVs on server-to-client keys. Here we use the exchange
5825 * hash from the _first_ key exchange.
5828 unsigned char keyspace
[SSH2_KEX_MAX_HASH_LEN
* SSH2_MKKEY_ITERS
];
5829 assert(sizeof(keyspace
) >= ssh
->kex
->hash
->hlen
* SSH2_MKKEY_ITERS
);
5830 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,'D',keyspace
);
5831 assert((ssh
->sccipher
->keylen
+7) / 8 <=
5832 ssh
->kex
->hash
->hlen
* SSH2_MKKEY_ITERS
);
5833 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
5834 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,'B',keyspace
);
5835 assert(ssh
->sccipher
->blksize
<=
5836 ssh
->kex
->hash
->hlen
* SSH2_MKKEY_ITERS
);
5837 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
5838 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,'F',keyspace
);
5839 assert(ssh
->scmac
->len
<=
5840 ssh
->kex
->hash
->hlen
* SSH2_MKKEY_ITERS
);
5841 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
5842 memset(keyspace
, 0, sizeof(keyspace
));
5844 logeventf(ssh
, "Initialised %.200s server->client encryption",
5845 ssh
->sccipher
->text_name
);
5846 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
5847 ssh
->scmac
->text_name
);
5848 if (ssh
->sccomp
->text_name
)
5849 logeventf(ssh
, "Initialised %s decompression",
5850 ssh
->sccomp
->text_name
);
5853 * Free key exchange data.
5857 if (!ssh
->kex
->pdata
) {
5863 * Key exchange is over. Loop straight back round if we have a
5864 * deferred rekey reason.
5866 if (ssh
->deferred_rekey_reason
) {
5867 logevent(ssh
->deferred_rekey_reason
);
5869 ssh
->deferred_rekey_reason
= NULL
;
5870 goto begin_key_exchange
;
5874 * Otherwise, schedule a timer for our next rekey.
5876 ssh
->kex_in_progress
= FALSE
;
5877 ssh
->last_rekey
= GETTICKCOUNT();
5878 if (ssh
->cfg
.ssh_rekey_time
!= 0)
5879 ssh
->next_rekey
= schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5883 * If this is the first key exchange phase, we must pass the
5884 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5885 * wants to see it but because it will need time to initialise
5886 * itself before it sees an actual packet. In subsequent key
5887 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5888 * it would only confuse the layer above.
5890 if (s
->activated_authconn
) {
5893 s
->activated_authconn
= TRUE
;
5896 * Now we're encrypting. Begin returning 1 to the protocol main
5897 * function so that other things can run on top of the
5898 * transport. If we ever see a KEXINIT, we must go back to the
5901 * We _also_ go back to the start if we see pktin==NULL and
5902 * inlen==-1, because this is a special signal meaning
5903 * `initiate client-driven rekey', and `in' contains a message
5904 * giving the reason for the rekey.
5906 while (!((pktin
&& pktin
->type
== SSH2_MSG_KEXINIT
) ||
5907 (!pktin
&& inlen
== -1))) {
5912 logevent("Server initiated key re-exchange");
5915 * Special case: if the server bug is set that doesn't
5916 * allow rekeying, we give a different log message and
5917 * continue waiting. (If such a server _initiates_ a rekey,
5918 * we process it anyway!)
5920 if ((ssh
->remote_bugs
& BUG_SSH2_REKEY
)) {
5921 logeventf(ssh
, "Server bug prevents key re-exchange (%s)",
5923 /* Reset the counters, so that at least this message doesn't
5924 * hit the event log _too_ often. */
5925 ssh
->outgoing_data_size
= 0;
5926 ssh
->incoming_data_size
= 0;
5927 if (ssh
->cfg
.ssh_rekey_time
!= 0) {
5929 schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5932 goto wait_for_rekey
; /* this is utterly horrid */
5934 logeventf(ssh
, "Initiating key re-exchange (%s)", (char *)in
);
5937 goto begin_key_exchange
;
5943 * Add data to an SSH-2 channel output buffer.
5945 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
5948 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
5952 * Attempt to send data on an SSH-2 channel.
5954 static int ssh2_try_send(struct ssh_channel
*c
)
5957 struct Packet
*pktout
;
5959 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
5962 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
5963 if ((unsigned)len
> c
->v
.v2
.remwindow
)
5964 len
= c
->v
.v2
.remwindow
;
5965 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
5966 len
= c
->v
.v2
.remmaxpkt
;
5967 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
5968 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5969 dont_log_data(ssh
, pktout
, PKTLOG_OMIT
);
5970 ssh2_pkt_addstring_start(pktout
);
5971 ssh2_pkt_addstring_data(pktout
, data
, len
);
5972 end_log_omission(ssh
, pktout
);
5973 ssh2_pkt_send(ssh
, pktout
);
5974 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
5975 c
->v
.v2
.remwindow
-= len
;
5979 * After having sent as much data as we can, return the amount
5982 return bufchain_size(&c
->v
.v2
.outbuffer
);
5985 static void ssh2_try_send_and_unthrottle(struct ssh_channel
*c
)
5989 return; /* don't send on closing channels */
5990 bufsize
= ssh2_try_send(c
);
5993 case CHAN_MAINSESSION
:
5994 /* stdin need not receive an unthrottle
5995 * notification since it will be polled */
5998 x11_unthrottle(c
->u
.x11
.s
);
6001 /* agent sockets are request/response and need no
6002 * buffer management */
6005 pfd_unthrottle(c
->u
.pfd
.s
);
6012 * Potentially enlarge the window on an SSH-2 channel.
6014 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
6019 * Never send WINDOW_ADJUST for a channel that the remote side
6020 * already thinks it's closed; there's no point, since it won't
6021 * be sending any more data anyway.
6027 * Only send a WINDOW_ADJUST if there's significantly more window
6028 * available than the other end thinks there is. This saves us
6029 * sending a WINDOW_ADJUST for every character in a shell session.
6031 * "Significant" is arbitrarily defined as half the window size.
6033 if (newwin
> c
->v
.v2
.locwindow
* 2) {
6034 struct Packet
*pktout
;
6036 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
6037 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6038 ssh2_pkt_adduint32(pktout
, newwin
- c
->v
.v2
.locwindow
);
6039 ssh2_pkt_send(ssh
, pktout
);
6040 c
->v
.v2
.locwindow
= newwin
;
6044 static void ssh2_msg_channel_window_adjust(Ssh ssh
, struct Packet
*pktin
)
6046 unsigned i
= ssh_pkt_getuint32(pktin
);
6047 struct ssh_channel
*c
;
6048 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6049 if (c
&& !c
->closes
) {
6050 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
6051 ssh2_try_send_and_unthrottle(c
);
6055 static void ssh2_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
6059 unsigned i
= ssh_pkt_getuint32(pktin
);
6060 struct ssh_channel
*c
;
6061 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6063 return; /* nonexistent channel */
6064 if (pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
6065 ssh_pkt_getuint32(pktin
) != SSH2_EXTENDED_DATA_STDERR
)
6066 return; /* extended but not stderr */
6067 ssh_pkt_getstring(pktin
, &data
, &length
);
6070 c
->v
.v2
.locwindow
-= length
;
6072 case CHAN_MAINSESSION
:
6074 from_backend(ssh
->frontend
, pktin
->type
==
6075 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
6079 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
6082 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
6085 while (length
> 0) {
6086 if (c
->u
.a
.lensofar
< 4) {
6087 unsigned int l
= min(4 - c
->u
.a
.lensofar
,
6089 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
6093 c
->u
.a
.lensofar
+= l
;
6095 if (c
->u
.a
.lensofar
== 4) {
6097 4 + GET_32BIT(c
->u
.a
.msglen
);
6098 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
6100 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
6102 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
6104 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
6106 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
6110 c
->u
.a
.lensofar
+= l
;
6112 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
6115 if (agent_query(c
->u
.a
.message
,
6118 ssh_agentf_callback
, c
))
6119 ssh_agentf_callback(c
, reply
, replylen
);
6120 sfree(c
->u
.a
.message
);
6121 c
->u
.a
.lensofar
= 0;
6128 * If we are not buffering too much data,
6129 * enlarge the window again at the remote side.
6131 if (bufsize
< OUR_V2_WINSIZE
)
6132 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
6136 static void ssh2_msg_channel_eof(Ssh ssh
, struct Packet
*pktin
)
6138 unsigned i
= ssh_pkt_getuint32(pktin
);
6139 struct ssh_channel
*c
;
6141 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6143 return; /* nonexistent channel */
6145 if (c
->type
== CHAN_X11
) {
6147 * Remote EOF on an X11 channel means we should
6148 * wrap up and close the channel ourselves.
6150 x11_close(c
->u
.x11
.s
);
6152 } else if (c
->type
== CHAN_AGENT
) {
6154 } else if (c
->type
== CHAN_SOCKDATA
) {
6155 pfd_close(c
->u
.pfd
.s
);
6160 static void ssh2_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
6162 unsigned i
= ssh_pkt_getuint32(pktin
);
6163 struct ssh_channel
*c
;
6164 struct Packet
*pktout
;
6166 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6167 if (!c
|| c
->halfopen
) {
6168 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
6169 c ?
"half-open" : "nonexistent", i
));
6172 /* Do pre-close processing on the channel. */
6174 case CHAN_MAINSESSION
:
6175 ssh
->mainchan
= NULL
;
6176 update_specials_menu(ssh
->frontend
);
6179 if (c
->u
.x11
.s
!= NULL
)
6180 x11_close(c
->u
.x11
.s
);
6187 if (c
->u
.pfd
.s
!= NULL
)
6188 pfd_close(c
->u
.pfd
.s
);
6192 if (c
->closes
== 0) {
6193 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
6194 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6195 ssh2_pkt_send(ssh
, pktout
);
6197 del234(ssh
->channels
, c
);
6198 bufchain_clear(&c
->v
.v2
.outbuffer
);
6202 * See if that was the last channel left open.
6203 * (This is only our termination condition if we're
6204 * not running in -N mode.)
6206 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
6208 * We used to send SSH_MSG_DISCONNECT here,
6209 * because I'd believed that _every_ conforming
6210 * SSH-2 connection had to end with a disconnect
6211 * being sent by at least one side; apparently
6212 * I was wrong and it's perfectly OK to
6213 * unceremoniously slam the connection shut
6214 * when you're done, and indeed OpenSSH feels
6215 * this is more polite than sending a
6216 * DISCONNECT. So now we don't.
6218 ssh_disconnect(ssh
, "All channels closed", NULL
, 0, TRUE
);
6222 static void ssh2_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
6224 unsigned i
= ssh_pkt_getuint32(pktin
);
6225 struct ssh_channel
*c
;
6226 struct Packet
*pktout
;
6228 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6230 return; /* nonexistent channel */
6231 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
6232 return; /* dunno why they're confirming this */
6233 c
->remoteid
= ssh_pkt_getuint32(pktin
);
6234 c
->halfopen
= FALSE
;
6235 c
->type
= CHAN_SOCKDATA
;
6236 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
6237 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
6239 pfd_confirm(c
->u
.pfd
.s
);
6242 * We have a pending close on this channel,
6243 * which we decided on before the server acked
6244 * the channel open. So now we know the
6245 * remoteid, we can close it again.
6247 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
6248 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6249 ssh2_pkt_send(ssh
, pktout
);
6253 static void ssh2_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
6255 static const char *const reasons
[] = {
6256 "<unknown reason code>",
6257 "Administratively prohibited",
6259 "Unknown channel type",
6260 "Resource shortage",
6262 unsigned i
= ssh_pkt_getuint32(pktin
);
6263 unsigned reason_code
;
6264 char *reason_string
;
6266 struct ssh_channel
*c
;
6267 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6269 return; /* nonexistent channel */
6270 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
6271 return; /* dunno why they're failing this */
6273 reason_code
= ssh_pkt_getuint32(pktin
);
6274 if (reason_code
>= lenof(reasons
))
6275 reason_code
= 0; /* ensure reasons[reason_code] in range */
6276 ssh_pkt_getstring(pktin
, &reason_string
, &reason_length
);
6277 logeventf(ssh
, "Forwarded connection refused by server: %s [%.*s]",
6278 reasons
[reason_code
], reason_length
, reason_string
);
6280 pfd_close(c
->u
.pfd
.s
);
6282 del234(ssh
->channels
, c
);
6286 static void ssh2_msg_channel_request(Ssh ssh
, struct Packet
*pktin
)
6290 int typelen
, want_reply
;
6291 int reply
= SSH2_MSG_CHANNEL_FAILURE
; /* default */
6292 struct ssh_channel
*c
;
6293 struct Packet
*pktout
;
6295 localid
= ssh_pkt_getuint32(pktin
);
6296 ssh_pkt_getstring(pktin
, &type
, &typelen
);
6297 want_reply
= ssh2_pkt_getbool(pktin
);
6300 * First, check that the channel exists. Otherwise,
6301 * we can instantly disconnect with a rude message.
6303 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
6305 char *buf
= dupprintf("Received channel request for nonexistent"
6306 " channel %d", localid
);
6307 ssh_disconnect(ssh
, NULL
, buf
, SSH2_DISCONNECT_PROTOCOL_ERROR
, FALSE
);
6313 * Having got the channel number, we now look at
6314 * the request type string to see if it's something
6317 if (c
== ssh
->mainchan
) {
6319 * We recognise "exit-status" and "exit-signal" on
6320 * the primary channel.
6322 if (typelen
== 11 &&
6323 !memcmp(type
, "exit-status", 11)) {
6325 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
6326 logeventf(ssh
, "Server sent command exit status %d",
6328 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
6330 } else if (typelen
== 11 &&
6331 !memcmp(type
, "exit-signal", 11)) {
6333 int is_plausible
= TRUE
, is_int
= FALSE
;
6334 char *fmt_sig
= "", *fmt_msg
= "";
6336 int msglen
= 0, core
= FALSE
;
6337 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
6338 * provide an `int' for the signal, despite its
6339 * having been a `string' in the drafts since at
6340 * least 2001. (Fixed in session.c 1.147.) Try to
6341 * infer which we can safely parse it as. */
6343 unsigned char *p
= pktin
->body
+
6345 long len
= pktin
->length
- pktin
->savedpos
;
6346 unsigned long num
= GET_32BIT(p
); /* what is it? */
6347 /* If it's 0, it hardly matters; assume string */
6351 int maybe_int
= FALSE
, maybe_str
= FALSE
;
6352 #define CHECK_HYPOTHESIS(offset, result) \
6355 if (q >= 0 && q+4 <= len) { \
6356 q = q + 4 + GET_32BIT(p+q); \
6357 if (q >= 0 && q+4 <= len && \
6358 ((q = q + 4 + GET_32BIT(p+q))!= 0) && q == len) \
6362 CHECK_HYPOTHESIS(4+1, maybe_int
);
6363 CHECK_HYPOTHESIS(4+num
+1, maybe_str
);
6364 #undef CHECK_HYPOTHESIS
6365 if (maybe_int
&& !maybe_str
)
6367 else if (!maybe_int
&& maybe_str
)
6370 /* Crikey. Either or neither. Panic. */
6371 is_plausible
= FALSE
;
6374 ssh
->exitcode
= 128; /* means `unknown signal' */
6377 /* Old non-standard OpenSSH. */
6378 int signum
= ssh_pkt_getuint32(pktin
);
6379 fmt_sig
= dupprintf(" %d", signum
);
6380 ssh
->exitcode
= 128 + signum
;
6382 /* As per the drafts. */
6385 ssh_pkt_getstring(pktin
, &sig
, &siglen
);
6386 /* Signal name isn't supposed to be blank, but
6387 * let's cope gracefully if it is. */
6389 fmt_sig
= dupprintf(" \"%.*s\"",
6394 * Really hideous method of translating the
6395 * signal description back into a locally
6396 * meaningful number.
6401 #define TRANSLATE_SIGNAL(s) \
6402 else if (siglen == lenof(#s)-1 && !memcmp(sig, #s, siglen)) \
6403 ssh->exitcode = 128 + SIG ## s
6405 TRANSLATE_SIGNAL(ABRT
);
6408 TRANSLATE_SIGNAL(ALRM
);
6411 TRANSLATE_SIGNAL(FPE
);
6414 TRANSLATE_SIGNAL(HUP
);
6417 TRANSLATE_SIGNAL(ILL
);
6420 TRANSLATE_SIGNAL(INT
);
6423 TRANSLATE_SIGNAL(KILL
);
6426 TRANSLATE_SIGNAL(PIPE
);
6429 TRANSLATE_SIGNAL(QUIT
);
6432 TRANSLATE_SIGNAL(SEGV
);
6435 TRANSLATE_SIGNAL(TERM
);
6438 TRANSLATE_SIGNAL(USR1
);
6441 TRANSLATE_SIGNAL(USR2
);
6443 #undef TRANSLATE_SIGNAL
6445 ssh
->exitcode
= 128;
6447 core
= ssh2_pkt_getbool(pktin
);
6448 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
6450 fmt_msg
= dupprintf(" (\"%.*s\")", msglen
, msg
);
6452 /* ignore lang tag */
6453 } /* else don't attempt to parse */
6454 logeventf(ssh
, "Server exited on signal%s%s%s",
6455 fmt_sig
, core ?
" (core dumped)" : "",
6457 if (*fmt_sig
) sfree(fmt_sig
);
6458 if (*fmt_msg
) sfree(fmt_msg
);
6459 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
6464 * This is a channel request we don't know
6465 * about, so we now either ignore the request
6466 * or respond with CHANNEL_FAILURE, depending
6469 reply
= SSH2_MSG_CHANNEL_FAILURE
;
6472 pktout
= ssh2_pkt_init(reply
);
6473 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6474 ssh2_pkt_send(ssh
, pktout
);
6478 static void ssh2_msg_global_request(Ssh ssh
, struct Packet
*pktin
)
6481 int typelen
, want_reply
;
6482 struct Packet
*pktout
;
6484 ssh_pkt_getstring(pktin
, &type
, &typelen
);
6485 want_reply
= ssh2_pkt_getbool(pktin
);
6488 * We currently don't support any global requests
6489 * at all, so we either ignore the request or
6490 * respond with REQUEST_FAILURE, depending on
6494 pktout
= ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
6495 ssh2_pkt_send(ssh
, pktout
);
6499 static void ssh2_msg_channel_open(Ssh ssh
, struct Packet
*pktin
)
6507 struct ssh_channel
*c
;
6508 unsigned remid
, winsize
, pktsize
;
6509 struct Packet
*pktout
;
6511 ssh_pkt_getstring(pktin
, &type
, &typelen
);
6512 c
= snew(struct ssh_channel
);
6515 remid
= ssh_pkt_getuint32(pktin
);
6516 winsize
= ssh_pkt_getuint32(pktin
);
6517 pktsize
= ssh_pkt_getuint32(pktin
);
6519 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
6522 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
6523 addrstr
= snewn(peeraddrlen
+1, char);
6524 memcpy(addrstr
, peeraddr
, peeraddrlen
);
6525 addrstr
[peeraddrlen
] = '\0';
6526 peerport
= ssh_pkt_getuint32(pktin
);
6528 logeventf(ssh
, "Received X11 connect request from %s:%d",
6531 if (!ssh
->X11_fwd_enabled
)
6532 error
= "X11 forwarding is not enabled";
6533 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
6534 ssh
->x11auth
, addrstr
, peerport
,
6535 &ssh
->cfg
) != NULL
) {
6536 error
= "Unable to open an X11 connection";
6538 logevent("Opening X11 forward connection succeeded");
6543 } else if (typelen
== 15 &&
6544 !memcmp(type
, "forwarded-tcpip", 15)) {
6545 struct ssh_rportfwd pf
, *realpf
;
6548 ssh_pkt_getstring(pktin
, &dummy
, &dummylen
);/* skip address */
6549 pf
.sport
= ssh_pkt_getuint32(pktin
);
6550 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
6551 peerport
= ssh_pkt_getuint32(pktin
);
6552 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
6553 logeventf(ssh
, "Received remote port %d open request "
6554 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
6555 if (realpf
== NULL
) {
6556 error
= "Remote port is not recognised";
6558 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
6562 realpf
->pfrec
->addressfamily
);
6563 logeventf(ssh
, "Attempting to forward remote port to "
6564 "%s:%d", realpf
->dhost
, realpf
->dport
);
6566 logeventf(ssh
, "Port open failed: %s", e
);
6567 error
= "Port open failed";
6569 logevent("Forwarded port opened successfully");
6570 c
->type
= CHAN_SOCKDATA
;
6573 } else if (typelen
== 22 &&
6574 !memcmp(type
, "auth-agent@openssh.com", 22)) {
6575 if (!ssh
->agentfwd_enabled
)
6576 error
= "Agent forwarding is not enabled";
6578 c
->type
= CHAN_AGENT
; /* identify channel type */
6579 c
->u
.a
.lensofar
= 0;
6582 error
= "Unsupported channel type requested";
6585 c
->remoteid
= remid
;
6586 c
->halfopen
= FALSE
;
6588 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
6589 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6590 ssh2_pkt_adduint32(pktout
, SSH2_OPEN_CONNECT_FAILED
);
6591 ssh2_pkt_addstring(pktout
, error
);
6592 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
6593 ssh2_pkt_send(ssh
, pktout
);
6594 logeventf(ssh
, "Rejected channel open: %s", error
);
6597 c
->localid
= alloc_channel_id(ssh
);
6599 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6600 c
->v
.v2
.remwindow
= winsize
;
6601 c
->v
.v2
.remmaxpkt
= pktsize
;
6602 bufchain_init(&c
->v
.v2
.outbuffer
);
6603 add234(ssh
->channels
, c
);
6604 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
6605 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6606 ssh2_pkt_adduint32(pktout
, c
->localid
);
6607 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);
6608 ssh2_pkt_adduint32(pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
6609 ssh2_pkt_send(ssh
, pktout
);
6614 * Buffer banner messages for later display at some convenient point.
6616 static void ssh2_msg_userauth_banner(Ssh ssh
, struct Packet
*pktin
)
6618 /* Arbitrary limit to prevent unbounded inflation of buffer */
6619 if (bufchain_size(&ssh
->banner
) <= 131072) {
6620 char *banner
= NULL
;
6622 ssh_pkt_getstring(pktin
, &banner
, &size
);
6624 bufchain_add(&ssh
->banner
, banner
, size
);
6628 /* Helper function to deal with sending tty modes for "pty-req" */
6629 static void ssh2_send_ttymode(void *data
, char *mode
, char *val
)
6631 struct Packet
*pktout
= (struct Packet
*)data
;
6633 unsigned int arg
= 0;
6634 while (strcmp(mode
, ssh_ttymodes
[i
].mode
) != 0) i
++;
6635 if (i
== lenof(ssh_ttymodes
)) return;
6636 switch (ssh_ttymodes
[i
].type
) {
6638 arg
= ssh_tty_parse_specchar(val
);
6641 arg
= ssh_tty_parse_boolean(val
);
6644 ssh2_pkt_addbyte(pktout
, ssh_ttymodes
[i
].opcode
);
6645 ssh2_pkt_adduint32(pktout
, arg
);
6649 * Handle the SSH-2 userauth and connection layers.
6651 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
6652 struct Packet
*pktin
)
6654 struct do_ssh2_authconn_state
{
6657 AUTH_TYPE_PUBLICKEY
,
6658 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
6659 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
6661 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
6662 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
6664 int done_service_req
;
6665 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
6666 int tried_pubkey_config
, done_agent
;
6667 int kbd_inter_refused
;
6669 prompts_t
*cur_prompt
;
6674 void *publickey_blob
;
6675 int publickey_bloblen
;
6676 int publickey_encrypted
;
6677 char *publickey_algorithm
;
6678 char *publickey_comment
;
6679 unsigned char agent_request
[5], *agent_response
, *agentp
;
6680 int agent_responselen
;
6681 unsigned char *pkblob_in_agent
;
6683 char *pkblob
, *alg
, *commentp
;
6684 int pklen
, alglen
, commentlen
;
6685 int siglen
, retlen
, len
;
6686 char *q
, *agentreq
, *ret
;
6688 int num_env
, env_left
, env_ok
;
6689 struct Packet
*pktout
;
6691 crState(do_ssh2_authconn_state
);
6693 crBegin(ssh
->do_ssh2_authconn_crstate
);
6695 s
->done_service_req
= FALSE
;
6696 s
->we_are_in
= FALSE
;
6697 if (!ssh
->cfg
.ssh_no_userauth
) {
6699 * Request userauth protocol, and await a response to it.
6701 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
6702 ssh2_pkt_addstring(s
->pktout
, "ssh-userauth");
6703 ssh2_pkt_send(ssh
, s
->pktout
);
6704 crWaitUntilV(pktin
);
6705 if (pktin
->type
== SSH2_MSG_SERVICE_ACCEPT
)
6706 s
->done_service_req
= TRUE
;
6708 if (!s
->done_service_req
) {
6710 * Request connection protocol directly, without authentication.
6712 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
6713 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");
6714 ssh2_pkt_send(ssh
, s
->pktout
);
6715 crWaitUntilV(pktin
);
6716 if (pktin
->type
== SSH2_MSG_SERVICE_ACCEPT
) {
6717 s
->we_are_in
= TRUE
; /* no auth required */
6719 bombout(("Server refused service request"));
6724 /* Arrange to be able to deal with any BANNERs that come in.
6725 * (We do this now as packets may come in during the next bit.) */
6726 bufchain_init(&ssh
->banner
);
6727 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] =
6728 ssh2_msg_userauth_banner
;
6731 * Misc one-time setup for authentication.
6733 s
->publickey_blob
= NULL
;
6734 if (!s
->we_are_in
) {
6737 * Load the public half of any configured public key file
6740 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
6742 logeventf(ssh
, "Reading private key file \"%.150s\"",
6743 filename_to_str(&ssh
->cfg
.keyfile
));
6744 keytype
= key_type(&ssh
->cfg
.keyfile
);
6745 if (keytype
== SSH_KEYTYPE_SSH2
) {
6748 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
6749 &s
->publickey_algorithm
,
6750 &s
->publickey_bloblen
,
6751 &s
->publickey_comment
, &error
);
6752 if (s
->publickey_blob
) {
6753 s
->publickey_encrypted
=
6754 ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, NULL
);
6757 logeventf(ssh
, "Unable to load private key (%s)",
6759 msgbuf
= dupprintf("Unable to load private key file "
6760 "\"%.150s\" (%s)\r\n",
6761 filename_to_str(&ssh
->cfg
.keyfile
),
6763 c_write_str(ssh
, msgbuf
);
6768 logeventf(ssh
, "Unable to use this key file (%s)",
6769 key_type_to_str(keytype
));
6770 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
6772 filename_to_str(&ssh
->cfg
.keyfile
),
6773 key_type_to_str(keytype
));
6774 c_write_str(ssh
, msgbuf
);
6776 s
->publickey_blob
= NULL
;
6781 * Find out about any keys Pageant has (but if there's a
6782 * public key configured, filter out all others).
6785 s
->agent_response
= NULL
;
6786 s
->pkblob_in_agent
= NULL
;
6787 if (ssh
->cfg
.tryagent
&& agent_exists()) {
6791 logevent("Pageant is running. Requesting keys.");
6793 /* Request the keys held by the agent. */
6794 PUT_32BIT(s
->agent_request
, 1);
6795 s
->agent_request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
6796 if (!agent_query(s
->agent_request
, 5, &r
, &s
->agent_responselen
,
6797 ssh_agent_callback
, ssh
)) {
6801 bombout(("Unexpected data from server while"
6802 " waiting for agent response"));
6805 } while (pktin
|| inlen
> 0);
6806 r
= ssh
->agent_response
;
6807 s
->agent_responselen
= ssh
->agent_response_len
;
6809 s
->agent_response
= (unsigned char *) r
;
6810 if (s
->agent_response
&& s
->agent_responselen
>= 5 &&
6811 s
->agent_response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
6814 p
= s
->agent_response
+ 5;
6815 s
->nkeys
= GET_32BIT(p
);
6817 logeventf(ssh
, "Pageant has %d SSH-2 keys", s
->nkeys
);
6818 if (s
->publickey_blob
) {
6819 /* See if configured key is in agent. */
6820 for (keyi
= 0; keyi
< s
->nkeys
; keyi
++) {
6821 s
->pklen
= GET_32BIT(p
);
6822 if (s
->pklen
== s
->publickey_bloblen
&&
6823 !memcmp(p
+4, s
->publickey_blob
,
6824 s
->publickey_bloblen
)) {
6825 logeventf(ssh
, "Pageant key #%d matches "
6826 "configured key file", keyi
);
6828 s
->pkblob_in_agent
= p
;
6832 p
+= GET_32BIT(p
) + 4; /* comment */
6834 if (!s
->pkblob_in_agent
) {
6835 logevent("Configured key file not in Pageant");
6845 * We repeat this whole loop, including the username prompt,
6846 * until we manage a successful authentication. If the user
6847 * types the wrong _password_, they can be sent back to the
6848 * beginning to try another username, if this is configured on.
6849 * (If they specify a username in the config, they are never
6850 * asked, even if they do give a wrong password.)
6852 * I think this best serves the needs of
6854 * - the people who have no configuration, no keys, and just
6855 * want to try repeated (username,password) pairs until they
6856 * type both correctly
6858 * - people who have keys and configuration but occasionally
6859 * need to fall back to passwords
6861 * - people with a key held in Pageant, who might not have
6862 * logged in to a particular machine before; so they want to
6863 * type a username, and then _either_ their key will be
6864 * accepted, _or_ they will type a password. If they mistype
6865 * the username they will want to be able to get back and
6868 s
->username
[0] = '\0';
6869 s
->got_username
= FALSE
;
6870 while (!s
->we_are_in
) {
6874 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
6876 * We got a username last time round this loop, and
6877 * with change_username turned off we don't try to get
6880 } else if (!*ssh
->cfg
.username
) {
6881 int ret
; /* need not be kept over crReturn */
6882 s
->cur_prompt
= new_prompts(ssh
->frontend
);
6883 s
->cur_prompt
->to_server
= TRUE
;
6884 s
->cur_prompt
->name
= dupstr("SSH login name");
6885 add_prompt(s
->cur_prompt
, dupstr("login as: "), TRUE
,
6886 lenof(s
->username
));
6887 ret
= get_userpass_input(s
->cur_prompt
, NULL
, 0);
6890 crWaitUntilV(!pktin
);
6891 ret
= get_userpass_input(s
->cur_prompt
, in
, inlen
);
6896 * get_userpass_input() failed to get a username.
6899 free_prompts(s
->cur_prompt
);
6900 ssh_disconnect(ssh
, "No username provided", NULL
, 0, TRUE
);
6903 memcpy(s
->username
, s
->cur_prompt
->prompts
[0]->result
,
6904 lenof(s
->username
));
6905 free_prompts(s
->cur_prompt
);
6908 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
6909 s
->username
[sizeof(s
->username
)-1] = '\0';
6910 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
6911 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
6912 c_write_str(ssh
, stuff
);
6916 s
->got_username
= TRUE
;
6919 * Send an authentication request using method "none": (a)
6920 * just in case it succeeds, and (b) so that we know what
6921 * authentication methods we can usefully try next.
6923 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6925 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6926 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6927 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");/* service requested */
6928 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6929 ssh2_pkt_send(ssh
, s
->pktout
);
6930 s
->type
= AUTH_TYPE_NONE
;
6932 s
->we_are_in
= FALSE
;
6934 s
->tried_pubkey_config
= FALSE
;
6935 s
->kbd_inter_refused
= FALSE
;
6937 /* Reset agent request state. */
6938 s
->done_agent
= FALSE
;
6939 if (s
->agent_response
) {
6940 if (s
->pkblob_in_agent
) {
6941 s
->agentp
= s
->pkblob_in_agent
;
6943 s
->agentp
= s
->agent_response
+ 5 + 4;
6950 * Wait for the result of the last authentication request.
6953 crWaitUntilV(pktin
);
6955 * Now is a convenient point to spew any banner material
6956 * that we've accumulated. (This should ensure that when
6957 * we exit the auth loop, we haven't any left to deal
6961 int size
= bufchain_size(&ssh
->banner
);
6963 * Don't show the banner if we're operating in
6964 * non-verbose non-interactive mode. (It's probably
6965 * a script, which means nobody will read the
6966 * banner _anyway_, and moreover the printing of
6967 * the banner will screw up processing on the
6968 * output of (say) plink.)
6970 if (size
&& (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
))) {
6971 char *banner
= snewn(size
, char);
6972 bufchain_fetch(&ssh
->banner
, banner
, size
);
6973 c_write_untrusted(ssh
, banner
, size
);
6976 bufchain_clear(&ssh
->banner
);
6978 if (pktin
->type
== SSH2_MSG_USERAUTH_SUCCESS
) {
6979 logevent("Access granted");
6980 s
->we_are_in
= TRUE
;
6984 if (pktin
->type
!= SSH2_MSG_USERAUTH_FAILURE
) {
6985 bombout(("Strange packet received during authentication: "
6986 "type %d", pktin
->type
));
6993 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6994 * we can look at the string in it and know what we can
6995 * helpfully try next.
6997 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
) {
7000 ssh_pkt_getstring(pktin
, &methods
, &methlen
);
7001 if (!ssh2_pkt_getbool(pktin
)) {
7003 * We have received an unequivocal Access
7004 * Denied. This can translate to a variety of
7007 * - if we'd just tried "none" authentication,
7008 * it's not worth printing anything at all
7010 * - if we'd just tried a public key _offer_,
7011 * the message should be "Server refused our
7012 * key" (or no message at all if the key
7013 * came from Pageant)
7015 * - if we'd just tried anything else, the
7016 * message really should be "Access denied".
7018 * Additionally, if we'd just tried password
7019 * authentication, we should break out of this
7020 * whole loop so as to go back to the username
7021 * prompt (iff we're configured to allow
7022 * username change attempts).
7024 if (s
->type
== AUTH_TYPE_NONE
) {
7026 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
7027 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
7028 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
7029 c_write_str(ssh
, "Server refused our key\r\n");
7030 logevent("Server refused public key");
7031 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
7032 /* server declined keyboard-interactive; ignore */
7034 c_write_str(ssh
, "Access denied\r\n");
7035 logevent("Access denied");
7036 if (s
->type
== AUTH_TYPE_PASSWORD
&&
7037 ssh
->cfg
.change_username
) {
7038 /* XXX perhaps we should allow
7039 * keyboard-interactive to do this too? */
7040 s
->we_are_in
= FALSE
;
7045 c_write_str(ssh
, "Further authentication required\r\n");
7046 logevent("Further authentication required");
7050 in_commasep_string("publickey", methods
, methlen
);
7052 in_commasep_string("password", methods
, methlen
);
7053 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
7054 in_commasep_string("keyboard-interactive", methods
, methlen
);
7057 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
7059 if (s
->can_pubkey
&& !s
->done_agent
&& s
->nkeys
) {
7062 * Attempt public-key authentication using a key from Pageant.
7065 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
7066 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
7068 logeventf(ssh
, "Trying Pageant key #%d", s
->keyi
);
7070 /* Unpack key from agent response */
7071 s
->pklen
= GET_32BIT(s
->agentp
);
7073 s
->pkblob
= (char *)s
->agentp
;
7074 s
->agentp
+= s
->pklen
;
7075 s
->alglen
= GET_32BIT(s
->pkblob
);
7076 s
->alg
= s
->pkblob
+ 4;
7077 s
->commentlen
= GET_32BIT(s
->agentp
);
7079 s
->commentp
= (char *)s
->agentp
;
7080 s
->agentp
+= s
->commentlen
;
7081 /* s->agentp now points at next key, if any */
7083 /* See if server will accept it */
7084 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
7085 ssh2_pkt_addstring(s
->pktout
, s
->username
);
7086 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");
7087 /* service requested */
7088 ssh2_pkt_addstring(s
->pktout
, "publickey");
7090 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
7091 ssh2_pkt_addstring_start(s
->pktout
);
7092 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
7093 ssh2_pkt_addstring_start(s
->pktout
);
7094 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
7095 ssh2_pkt_send(ssh
, s
->pktout
);
7096 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_QUIET
;
7098 crWaitUntilV(pktin
);
7099 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
7101 /* Offer of key refused. */
7108 if (flags
& FLAG_VERBOSE
) {
7109 c_write_str(ssh
, "Authenticating with "
7111 c_write(ssh
, s
->commentp
, s
->commentlen
);
7112 c_write_str(ssh
, "\" from agent\r\n");
7116 * Server is willing to accept the key.
7117 * Construct a SIGN_REQUEST.
7119 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
7120 ssh2_pkt_addstring(s
->pktout
, s
->username
);
7121 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");
7122 /* service requested */
7123 ssh2_pkt_addstring(s
->pktout
, "publickey");
7125 ssh2_pkt_addbool(s
->pktout
, TRUE
); /* signature included */
7126 ssh2_pkt_addstring_start(s
->pktout
);
7127 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
7128 ssh2_pkt_addstring_start(s
->pktout
);
7129 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
7131 /* Ask agent for signature. */
7132 s
->siglen
= s
->pktout
->length
- 5 + 4 +
7133 ssh
->v2_session_id_len
;
7134 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
7136 s
->len
= 1; /* message type */
7137 s
->len
+= 4 + s
->pklen
; /* key blob */
7138 s
->len
+= 4 + s
->siglen
; /* data to sign */
7139 s
->len
+= 4; /* flags */
7140 s
->agentreq
= snewn(4 + s
->len
, char);
7141 PUT_32BIT(s
->agentreq
, s
->len
);
7142 s
->q
= s
->agentreq
+ 4;
7143 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
7144 PUT_32BIT(s
->q
, s
->pklen
);
7146 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
7148 PUT_32BIT(s
->q
, s
->siglen
);
7150 /* Now the data to be signed... */
7151 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
7152 PUT_32BIT(s
->q
, ssh
->v2_session_id_len
);
7155 memcpy(s
->q
, ssh
->v2_session_id
,
7156 ssh
->v2_session_id_len
);
7157 s
->q
+= ssh
->v2_session_id_len
;
7158 memcpy(s
->q
, s
->pktout
->data
+ 5,
7159 s
->pktout
->length
- 5);
7160 s
->q
+= s
->pktout
->length
- 5;
7161 /* And finally the (zero) flags word. */
7163 if (!agent_query(s
->agentreq
, s
->len
+ 4,
7165 ssh_agent_callback
, ssh
)) {
7169 bombout(("Unexpected data from server"
7170 " while waiting for agent"
7174 } while (pktin
|| inlen
> 0);
7175 vret
= ssh
->agent_response
;
7176 s
->retlen
= ssh
->agent_response_len
;
7181 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
7182 logevent("Sending Pageant's response");
7183 ssh2_add_sigblob(ssh
, s
->pktout
,
7184 s
->pkblob
, s
->pklen
,
7186 GET_32BIT(s
->ret
+ 5));
7187 ssh2_pkt_send(ssh
, s
->pktout
);
7188 s
->type
= AUTH_TYPE_PUBLICKEY
;
7190 /* FIXME: less drastic response */
7191 bombout(("Pageant failed to answer challenge"));
7197 /* Do we have any keys left to try? */
7198 if (s
->pkblob_in_agent
) {
7199 s
->done_agent
= TRUE
;
7200 s
->tried_pubkey_config
= TRUE
;
7203 if (s
->keyi
>= s
->nkeys
)
7204 s
->done_agent
= TRUE
;
7207 } else if (s
->can_pubkey
&& s
->publickey_blob
&&
7208 !s
->tried_pubkey_config
) {
7210 struct ssh2_userkey
*key
; /* not live over crReturn */
7211 char *passphrase
; /* not live over crReturn */
7213 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
7214 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
7216 s
->tried_pubkey_config
= TRUE
;
7219 * Try the public key supplied in the configuration.
7221 * First, offer the public blob to see if the server is
7222 * willing to accept it.
7224 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
7225 ssh2_pkt_addstring(s
->pktout
, s
->username
);
7226 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");
7227 /* service requested */
7228 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
7229 ssh2_pkt_addbool(s
->pktout
, FALSE
);
7230 /* no signature included */
7231 ssh2_pkt_addstring(s
->pktout
, s
->publickey_algorithm
);
7232 ssh2_pkt_addstring_start(s
->pktout
);
7233 ssh2_pkt_addstring_data(s
->pktout
,
7234 (char *)s
->publickey_blob
,
7235 s
->publickey_bloblen
);
7236 ssh2_pkt_send(ssh
, s
->pktout
);
7237 logevent("Offered public key");
7239 crWaitUntilV(pktin
);
7240 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
7241 /* Key refused. Give up. */
7242 s
->gotit
= TRUE
; /* reconsider message next loop */
7243 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
7244 continue; /* process this new message */
7246 logevent("Offer of public key accepted");
7249 * Actually attempt a serious authentication using
7252 if (flags
& FLAG_VERBOSE
) {
7253 c_write_str(ssh
, "Authenticating with public key \"");
7254 c_write_str(ssh
, s
->publickey_comment
);
7255 c_write_str(ssh
, "\"\r\n");
7259 const char *error
; /* not live over crReturn */
7260 if (s
->publickey_encrypted
) {
7262 * Get a passphrase from the user.
7264 int ret
; /* need not be kept over crReturn */
7265 s
->cur_prompt
= new_prompts(ssh
->frontend
);
7266 s
->cur_prompt
->to_server
= FALSE
;
7267 s
->cur_prompt
->name
= dupstr("SSH key passphrase");
7268 add_prompt(s
->cur_prompt
,
7269 dupprintf("Passphrase for key \"%.100s\": ",
7270 s
->publickey_comment
),
7271 FALSE
, SSH_MAX_PASSWORD_LEN
);
7272 ret
= get_userpass_input(s
->cur_prompt
, NULL
, 0);
7275 crWaitUntilV(!pktin
);
7276 ret
= get_userpass_input(s
->cur_prompt
,
7281 /* Failed to get a passphrase. Terminate. */
7282 free_prompts(s
->cur_prompt
);
7283 ssh_disconnect(ssh
, NULL
,
7284 "Unable to authenticate",
7285 SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER
,
7290 dupstr(s
->cur_prompt
->prompts
[0]->result
);
7291 free_prompts(s
->cur_prompt
);
7293 passphrase
= NULL
; /* no passphrase needed */
7297 * Try decrypting the key.
7299 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, passphrase
,
7302 /* burn the evidence */
7303 memset(passphrase
, 0, strlen(passphrase
));
7306 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
7308 (key
== SSH2_WRONG_PASSPHRASE
)) {
7309 c_write_str(ssh
, "Wrong passphrase\r\n");
7311 /* and loop again */
7313 c_write_str(ssh
, "Unable to load private key (");
7314 c_write_str(ssh
, error
);
7315 c_write_str(ssh
, ")\r\n");
7317 break; /* try something else */
7323 unsigned char *pkblob
, *sigblob
, *sigdata
;
7324 int pkblob_len
, sigblob_len
, sigdata_len
;
7328 * We have loaded the private key and the server
7329 * has announced that it's willing to accept it.
7330 * Hallelujah. Generate a signature and send it.
7332 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
7333 ssh2_pkt_addstring(s
->pktout
, s
->username
);
7334 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");
7335 /* service requested */
7336 ssh2_pkt_addstring(s
->pktout
, "publickey");
7338 ssh2_pkt_addbool(s
->pktout
, TRUE
);
7339 /* signature follows */
7340 ssh2_pkt_addstring(s
->pktout
, key
->alg
->name
);
7341 pkblob
= key
->alg
->public_blob(key
->data
,
7343 ssh2_pkt_addstring_start(s
->pktout
);
7344 ssh2_pkt_addstring_data(s
->pktout
, (char *)pkblob
,
7348 * The data to be signed is:
7352 * followed by everything so far placed in the
7355 sigdata_len
= s
->pktout
->length
- 5 + 4 +
7356 ssh
->v2_session_id_len
;
7357 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
7359 sigdata
= snewn(sigdata_len
, unsigned char);
7361 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
7362 PUT_32BIT(sigdata
+p
, ssh
->v2_session_id_len
);
7365 memcpy(sigdata
+p
, ssh
->v2_session_id
,
7366 ssh
->v2_session_id_len
);
7367 p
+= ssh
->v2_session_id_len
;
7368 memcpy(sigdata
+p
, s
->pktout
->data
+ 5,
7369 s
->pktout
->length
- 5);
7370 p
+= s
->pktout
->length
- 5;
7371 assert(p
== sigdata_len
);
7372 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
7373 sigdata_len
, &sigblob_len
);
7374 ssh2_add_sigblob(ssh
, s
->pktout
, pkblob
, pkblob_len
,
7375 sigblob
, sigblob_len
);
7380 ssh2_pkt_send(ssh
, s
->pktout
);
7381 s
->type
= AUTH_TYPE_PUBLICKEY
;
7382 key
->alg
->freekey(key
->data
);
7385 } else if (s
->can_keyb_inter
&& !s
->kbd_inter_refused
) {
7388 * Keyboard-interactive authentication.
7391 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
7393 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
7394 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
7396 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
7397 ssh2_pkt_addstring(s
->pktout
, s
->username
);
7398 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");
7399 /* service requested */
7400 ssh2_pkt_addstring(s
->pktout
, "keyboard-interactive");
7402 ssh2_pkt_addstring(s
->pktout
, ""); /* lang */
7403 ssh2_pkt_addstring(s
->pktout
, ""); /* submethods */
7404 ssh2_pkt_send(ssh
, s
->pktout
);
7406 crWaitUntilV(pktin
);
7407 if (pktin
->type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
7408 /* Server is not willing to do keyboard-interactive
7409 * at all (or, bizarrely but legally, accepts the
7410 * user without actually issuing any prompts).
7411 * Give up on it entirely. */
7413 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
)
7414 logevent("Keyboard-interactive authentication refused");
7415 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
7416 s
->kbd_inter_refused
= TRUE
; /* don't try it again */
7421 * Loop while the server continues to send INFO_REQUESTs.
7423 while (pktin
->type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
7425 char *name
, *inst
, *lang
;
7426 int name_len
, inst_len
, lang_len
;
7430 * We've got a fresh USERAUTH_INFO_REQUEST.
7431 * Get the preamble and start building a prompt.
7433 ssh_pkt_getstring(pktin
, &name
, &name_len
);
7434 ssh_pkt_getstring(pktin
, &inst
, &inst_len
);
7435 ssh_pkt_getstring(pktin
, &lang
, &lang_len
);
7436 s
->cur_prompt
= new_prompts(ssh
->frontend
);
7437 s
->cur_prompt
->to_server
= TRUE
;
7439 /* FIXME: better prefix to distinguish from
7441 s
->cur_prompt
->name
=
7442 dupprintf("SSH server: %.*s", name_len
, name
);
7443 s
->cur_prompt
->name_reqd
= TRUE
;
7445 s
->cur_prompt
->name
=
7446 dupstr("SSH server authentication");
7447 s
->cur_prompt
->name_reqd
= FALSE
;
7449 /* FIXME: ugly to print "Using..." in prompt _every_
7450 * time round. Can this be done more subtly? */
7451 s
->cur_prompt
->instruction
=
7452 dupprintf("Using keyboard-interactive authentication.%s%.*s",
7453 inst_len ?
"\n" : "", inst_len
, inst
);
7454 s
->cur_prompt
->instr_reqd
= TRUE
;
7457 * Get the prompts from the packet.
7459 s
->num_prompts
= ssh_pkt_getuint32(pktin
);
7460 for (i
= 0; i
< s
->num_prompts
; i
++) {
7464 static char noprompt
[] =
7465 "<server failed to send prompt>: ";
7467 ssh_pkt_getstring(pktin
, &prompt
, &prompt_len
);
7468 echo
= ssh2_pkt_getbool(pktin
);
7471 prompt_len
= lenof(noprompt
)-1;
7473 add_prompt(s
->cur_prompt
,
7474 dupprintf("%.*s", prompt_len
, prompt
),
7475 echo
, SSH_MAX_PASSWORD_LEN
);
7479 * Get the user's responses.
7481 if (s
->num_prompts
) {
7482 int ret
; /* not live over crReturn */
7483 ret
= get_userpass_input(s
->cur_prompt
, NULL
, 0);
7486 crWaitUntilV(!pktin
);
7487 ret
= get_userpass_input(s
->cur_prompt
, in
, inlen
);
7492 * Failed to get responses. Terminate.
7494 free_prompts(s
->cur_prompt
);
7495 ssh_disconnect(ssh
, NULL
, "Unable to authenticate",
7496 SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER
,
7503 * Send the responses to the server.
7505 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
7506 ssh2_pkt_adduint32(s
->pktout
, s
->num_prompts
);
7507 for (i
=0; i
< s
->num_prompts
; i
++) {
7508 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
7509 ssh2_pkt_addstring(s
->pktout
,
7510 s
->cur_prompt
->prompts
[i
]->result
);
7511 end_log_omission(ssh
, s
->pktout
);
7513 ssh2_pkt_send_with_padding(ssh
, s
->pktout
, 256);
7516 * Get the next packet in case it's another
7519 crWaitUntilV(pktin
);
7524 * We should have SUCCESS or FAILURE now.
7528 } else if (s
->can_passwd
) {
7531 * Plain old password authentication.
7533 int ret
; /* not live over crReturn */
7534 int changereq_first_time
; /* not live over crReturn */
7536 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
7537 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
7539 s
->cur_prompt
= new_prompts(ssh
->frontend
);
7540 s
->cur_prompt
->to_server
= TRUE
;
7541 s
->cur_prompt
->name
= dupstr("SSH password");
7542 add_prompt(s
->cur_prompt
, dupprintf("%.90s@%.90s's password: ",
7545 FALSE
, SSH_MAX_PASSWORD_LEN
);
7547 ret
= get_userpass_input(s
->cur_prompt
, NULL
, 0);
7550 crWaitUntilV(!pktin
);
7551 ret
= get_userpass_input(s
->cur_prompt
, in
, inlen
);
7556 * Failed to get responses. Terminate.
7558 free_prompts(s
->cur_prompt
);
7559 ssh_disconnect(ssh
, NULL
, "Unable to authenticate",
7560 SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER
,
7565 * Squirrel away the password. (We may need it later if
7566 * asked to change it.)
7568 s
->password
= dupstr(s
->cur_prompt
->prompts
[0]->result
);
7569 free_prompts(s
->cur_prompt
);
7572 * Send the password packet.
7574 * We pad out the password packet to 256 bytes to make
7575 * it harder for an attacker to find the length of the
7578 * Anyone using a password longer than 256 bytes
7579 * probably doesn't have much to worry about from
7580 * people who find out how long their password is!
7582 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
7583 ssh2_pkt_addstring(s
->pktout
, s
->username
);
7584 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");
7585 /* service requested */
7586 ssh2_pkt_addstring(s
->pktout
, "password");
7587 ssh2_pkt_addbool(s
->pktout
, FALSE
);
7588 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
7589 ssh2_pkt_addstring(s
->pktout
, s
->password
);
7590 end_log_omission(ssh
, s
->pktout
);
7591 ssh2_pkt_send_with_padding(ssh
, s
->pktout
, 256);
7592 logevent("Sent password");
7593 s
->type
= AUTH_TYPE_PASSWORD
;
7596 * Wait for next packet, in case it's a password change
7599 crWaitUntilV(pktin
);
7600 changereq_first_time
= TRUE
;
7602 while (pktin
->type
== SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
) {
7605 * We're being asked for a new password
7606 * (perhaps not for the first time).
7607 * Loop until the server accepts it.
7610 int got_new
= FALSE
; /* not live over crReturn */
7611 char *prompt
; /* not live over crReturn */
7612 int prompt_len
; /* not live over crReturn */
7616 if (changereq_first_time
)
7617 msg
= "Server requested password change";
7619 msg
= "Server rejected new password";
7621 c_write_str(ssh
, msg
);
7622 c_write_str(ssh
, "\r\n");
7625 ssh_pkt_getstring(pktin
, &prompt
, &prompt_len
);
7627 s
->cur_prompt
= new_prompts(ssh
->frontend
);
7628 s
->cur_prompt
->to_server
= TRUE
;
7629 s
->cur_prompt
->name
= dupstr("New SSH password");
7630 s
->cur_prompt
->instruction
=
7631 dupprintf("%.*s", prompt_len
, prompt
);
7632 s
->cur_prompt
->instr_reqd
= TRUE
;
7634 * There's no explicit requirement in the protocol
7635 * for the "old" passwords in the original and
7636 * password-change messages to be the same, and
7637 * apparently some Cisco kit supports password change
7638 * by the user entering a blank password originally
7639 * and the real password subsequently, so,
7640 * reluctantly, we prompt for the old password again.
7642 * (On the other hand, some servers don't even bother
7643 * to check this field.)
7645 add_prompt(s
->cur_prompt
,
7646 dupstr("Current password (blank for previously entered password): "),
7647 FALSE
, SSH_MAX_PASSWORD_LEN
);
7648 add_prompt(s
->cur_prompt
, dupstr("Enter new password: "),
7649 FALSE
, SSH_MAX_PASSWORD_LEN
);
7650 add_prompt(s
->cur_prompt
, dupstr("Confirm new password: "),
7651 FALSE
, SSH_MAX_PASSWORD_LEN
);
7654 * Loop until the user manages to enter the same
7659 ret
= get_userpass_input(s
->cur_prompt
, NULL
, 0);
7662 crWaitUntilV(!pktin
);
7663 ret
= get_userpass_input(s
->cur_prompt
, in
, inlen
);
7668 * Failed to get responses. Terminate.
7670 /* burn the evidence */
7671 free_prompts(s
->cur_prompt
);
7672 memset(s
->password
, 0, strlen(s
->password
));
7674 ssh_disconnect(ssh
, NULL
, "Unable to authenticate",
7675 SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER
,
7681 * If the user specified a new original password
7682 * (IYSWIM), overwrite any previously specified
7684 * (A side effect is that the user doesn't have to
7685 * re-enter it if they louse up the new password.)
7687 if (s
->cur_prompt
->prompts
[0]->result
[0]) {
7688 memset(s
->password
, 0, strlen(s
->password
));
7689 /* burn the evidence */
7692 dupstr(s
->cur_prompt
->prompts
[0]->result
);
7696 * Check the two new passwords match.
7698 got_new
= (strcmp(s
->cur_prompt
->prompts
[1]->result
,
7699 s
->cur_prompt
->prompts
[2]->result
)
7702 /* They don't. Silly user. */
7703 c_write_str(ssh
, "Passwords do not match\r\n");
7708 * Send the new password (along with the old one).
7709 * (see above for padding rationale)
7711 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
7712 ssh2_pkt_addstring(s
->pktout
, s
->username
);
7713 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");
7714 /* service requested */
7715 ssh2_pkt_addstring(s
->pktout
, "password");
7716 ssh2_pkt_addbool(s
->pktout
, TRUE
);
7717 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
7718 ssh2_pkt_addstring(s
->pktout
, s
->password
);
7719 ssh2_pkt_addstring(s
->pktout
,
7720 s
->cur_prompt
->prompts
[1]->result
);
7721 free_prompts(s
->cur_prompt
);
7722 end_log_omission(ssh
, s
->pktout
);
7723 ssh2_pkt_send_with_padding(ssh
, s
->pktout
, 256);
7724 logevent("Sent new password");
7727 * Now see what the server has to say about it.
7728 * (If it's CHANGEREQ again, it's not happy with the
7731 crWaitUntilV(pktin
);
7732 changereq_first_time
= FALSE
;
7737 * We need to reexamine the current pktin at the top
7738 * of the loop. Either:
7739 * - we weren't asked to change password at all, in
7740 * which case it's a SUCCESS or FAILURE with the
7742 * - we sent a new password, and the server was
7743 * either OK with it (SUCCESS or FAILURE w/partial
7744 * success) or unhappy with the _old_ password
7745 * (FAILURE w/o partial success)
7746 * In any of these cases, we go back to the top of
7747 * the loop and start again.
7752 * We don't need the old password any more, in any
7753 * case. Burn the evidence.
7755 memset(s
->password
, 0, strlen(s
->password
));
7760 ssh_disconnect(ssh
, NULL
,
7761 "No supported authentication methods available",
7762 SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE
,
7770 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
7772 /* Clear up various bits and pieces from authentication. */
7773 if (s
->publickey_blob
) {
7774 sfree(s
->publickey_blob
);
7775 sfree(s
->publickey_comment
);
7777 if (s
->agent_response
)
7778 sfree(s
->agent_response
);
7781 * Now the connection protocol has started, one way or another.
7784 ssh
->channels
= newtree234(ssh_channelcmp
);
7787 * Set up handlers for some connection protocol messages, so we
7788 * don't have to handle them repeatedly in this coroutine.
7790 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] =
7791 ssh2_msg_channel_window_adjust
;
7792 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] =
7793 ssh2_msg_global_request
;
7796 * Create the main session channel.
7798 if (ssh
->cfg
.ssh_no_shell
) {
7799 ssh
->mainchan
= NULL
;
7800 } else if (*ssh
->cfg
.ssh_nc_host
) {
7802 * Just start a direct-tcpip channel and use it as the main
7805 ssh
->mainchan
= snew(struct ssh_channel
);
7806 ssh
->mainchan
->ssh
= ssh
;
7807 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
7809 "Opening direct-tcpip channel to %s:%d in place of session",
7810 ssh
->cfg
.ssh_nc_host
, ssh
->cfg
.ssh_nc_port
);
7811 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
7812 ssh2_pkt_addstring(s
->pktout
, "direct-tcpip");
7813 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->localid
);
7814 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7815 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
7816 ssh2_pkt_adduint32(s
->pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
7817 ssh2_pkt_addstring(s
->pktout
, ssh
->cfg
.ssh_nc_host
);
7818 ssh2_pkt_adduint32(s
->pktout
, ssh
->cfg
.ssh_nc_port
);
7820 * There's nothing meaningful to put in the originator
7821 * fields, but some servers insist on syntactically correct
7824 ssh2_pkt_addstring(s
->pktout
, "0.0.0.0");
7825 ssh2_pkt_adduint32(s
->pktout
, 0);
7826 ssh2_pkt_send(ssh
, s
->pktout
);
7828 crWaitUntilV(pktin
);
7829 if (pktin
->type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
7830 bombout(("Server refused to open a direct-tcpip channel"));
7832 /* FIXME: error data comes back in FAILURE packet */
7834 if (ssh_pkt_getuint32(pktin
) != ssh
->mainchan
->localid
) {
7835 bombout(("Server's channel confirmation cited wrong channel"));
7838 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(pktin
);
7839 ssh
->mainchan
->halfopen
= FALSE
;
7840 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
7841 ssh
->mainchan
->closes
= 0;
7842 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
7843 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
7844 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
7845 add234(ssh
->channels
, ssh
->mainchan
);
7846 update_specials_menu(ssh
->frontend
);
7847 logevent("Opened direct-tcpip channel");
7850 ssh
->mainchan
= snew(struct ssh_channel
);
7851 ssh
->mainchan
->ssh
= ssh
;
7852 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
7853 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
7854 ssh2_pkt_addstring(s
->pktout
, "session");
7855 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->localid
);
7856 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7857 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
7858 ssh2_pkt_adduint32(s
->pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
7859 ssh2_pkt_send(ssh
, s
->pktout
);
7860 crWaitUntilV(pktin
);
7861 if (pktin
->type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
7862 bombout(("Server refused to open a session"));
7864 /* FIXME: error data comes back in FAILURE packet */
7866 if (ssh_pkt_getuint32(pktin
) != ssh
->mainchan
->localid
) {
7867 bombout(("Server's channel confirmation cited wrong channel"));
7870 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(pktin
);
7871 ssh
->mainchan
->halfopen
= FALSE
;
7872 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
7873 ssh
->mainchan
->closes
= 0;
7874 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
7875 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
7876 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
7877 add234(ssh
->channels
, ssh
->mainchan
);
7878 update_specials_menu(ssh
->frontend
);
7879 logevent("Opened channel for session");
7880 ssh
->ncmode
= FALSE
;
7884 * Now we have a channel, make dispatch table entries for
7885 * general channel-based messages.
7887 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] =
7888 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] =
7889 ssh2_msg_channel_data
;
7890 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = ssh2_msg_channel_eof
;
7891 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = ssh2_msg_channel_close
;
7892 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] =
7893 ssh2_msg_channel_open_confirmation
;
7894 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] =
7895 ssh2_msg_channel_open_failure
;
7896 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] =
7897 ssh2_msg_channel_request
;
7898 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] =
7899 ssh2_msg_channel_open
;
7902 * Potentially enable X11 forwarding.
7904 if (ssh
->mainchan
&& !ssh
->ncmode
&& ssh
->cfg
.x11_forward
) {
7905 char proto
[20], data
[64];
7906 logevent("Requesting X11 forwarding");
7907 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
7908 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
7909 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
7910 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7911 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7912 ssh2_pkt_addstring(s
->pktout
, "x11-req");
7913 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7914 ssh2_pkt_addbool(s
->pktout
, 0); /* many connections */
7915 ssh2_pkt_addstring(s
->pktout
, proto
);
7917 * Note that while we blank the X authentication data here, we don't
7918 * take any special action to blank the start of an X11 channel,
7919 * so using MIT-MAGIC-COOKIE-1 and actually opening an X connection
7920 * without having session blanking enabled is likely to leak your
7921 * cookie into the log.
7923 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
7924 ssh2_pkt_addstring(s
->pktout
, data
);
7925 end_log_omission(ssh
, s
->pktout
);
7926 ssh2_pkt_adduint32(s
->pktout
, x11_get_screen_number(ssh
->cfg
.x11_display
));
7927 ssh2_pkt_send(ssh
, s
->pktout
);
7929 crWaitUntilV(pktin
);
7931 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7932 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7933 bombout(("Unexpected response to X11 forwarding request:"
7934 " packet type %d", pktin
->type
));
7937 logevent("X11 forwarding refused");
7939 logevent("X11 forwarding enabled");
7940 ssh
->X11_fwd_enabled
= TRUE
;
7945 * Enable port forwardings.
7947 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
7950 * Potentially enable agent forwarding.
7952 if (ssh
->mainchan
&& !ssh
->ncmode
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
7953 logevent("Requesting OpenSSH-style agent forwarding");
7954 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7955 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7956 ssh2_pkt_addstring(s
->pktout
, "auth-agent-req@openssh.com");
7957 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7958 ssh2_pkt_send(ssh
, s
->pktout
);
7960 crWaitUntilV(pktin
);
7962 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7963 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7964 bombout(("Unexpected response to agent forwarding request:"
7965 " packet type %d", pktin
->type
));
7968 logevent("Agent forwarding refused");
7970 logevent("Agent forwarding enabled");
7971 ssh
->agentfwd_enabled
= TRUE
;
7976 * Now allocate a pty for the session.
7978 if (ssh
->mainchan
&& !ssh
->ncmode
&& !ssh
->cfg
.nopty
) {
7979 /* Unpick the terminal-speed string. */
7980 /* XXX perhaps we should allow no speeds to be sent. */
7981 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
7982 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
7983 /* Build the pty request. */
7984 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7985 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7986 ssh2_pkt_addstring(s
->pktout
, "pty-req");
7987 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7988 ssh2_pkt_addstring(s
->pktout
, ssh
->cfg
.termtype
);
7989 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_width
);
7990 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_height
);
7991 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel width */
7992 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel height */
7993 ssh2_pkt_addstring_start(s
->pktout
);
7994 parse_ttymodes(ssh
, ssh
->cfg
.ttymodes
,
7995 ssh2_send_ttymode
, (void *)s
->pktout
);
7996 ssh2_pkt_addbyte(s
->pktout
, SSH2_TTY_OP_ISPEED
);
7997 ssh2_pkt_adduint32(s
->pktout
, ssh
->ispeed
);
7998 ssh2_pkt_addbyte(s
->pktout
, SSH2_TTY_OP_OSPEED
);
7999 ssh2_pkt_adduint32(s
->pktout
, ssh
->ospeed
);
8000 ssh2_pkt_addstring_data(s
->pktout
, "\0", 1); /* TTY_OP_END */
8001 ssh2_pkt_send(ssh
, s
->pktout
);
8002 ssh
->state
= SSH_STATE_INTERMED
;
8004 crWaitUntilV(pktin
);
8006 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
8007 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
8008 bombout(("Unexpected response to pty request:"
8009 " packet type %d", pktin
->type
));
8012 c_write_str(ssh
, "Server refused to allocate pty\r\n");
8013 ssh
->editing
= ssh
->echoing
= 1;
8015 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
8016 ssh
->ospeed
, ssh
->ispeed
);
8019 ssh
->editing
= ssh
->echoing
= 1;
8023 * Send environment variables.
8025 * Simplest thing here is to send all the requests at once, and
8026 * then wait for a whole bunch of successes or failures.
8028 if (ssh
->mainchan
&& !ssh
->ncmode
&& *ssh
->cfg
.environmt
) {
8029 char *e
= ssh
->cfg
.environmt
;
8030 char *var
, *varend
, *val
;
8036 while (*e
&& *e
!= '\t') e
++;
8038 if (*e
== '\t') e
++;
8043 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
8044 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
8045 ssh2_pkt_addstring(s
->pktout
, "env");
8046 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
8047 ssh2_pkt_addstring_start(s
->pktout
);
8048 ssh2_pkt_addstring_data(s
->pktout
, var
, varend
-var
);
8049 ssh2_pkt_addstring(s
->pktout
, val
);
8050 ssh2_pkt_send(ssh
, s
->pktout
);
8055 logeventf(ssh
, "Sent %d environment variables", s
->num_env
);
8058 s
->env_left
= s
->num_env
;
8060 while (s
->env_left
> 0) {
8061 crWaitUntilV(pktin
);
8063 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
8064 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
8065 bombout(("Unexpected response to environment request:"
8066 " packet type %d", pktin
->type
));
8076 if (s
->env_ok
== s
->num_env
) {
8077 logevent("All environment variables successfully set");
8078 } else if (s
->env_ok
== 0) {
8079 logevent("All environment variables refused");
8080 c_write_str(ssh
, "Server refused to set environment variables\r\n");
8082 logeventf(ssh
, "%d environment variables refused",
8083 s
->num_env
- s
->env_ok
);
8084 c_write_str(ssh
, "Server refused to set all environment variables\r\n");
8089 * Start a shell or a remote command. We may have to attempt
8090 * this twice if the config data has provided a second choice
8093 if (ssh
->mainchan
&& !ssh
->ncmode
) while (1) {
8097 if (ssh
->fallback_cmd
) {
8098 subsys
= ssh
->cfg
.ssh_subsys2
;
8099 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
8101 subsys
= ssh
->cfg
.ssh_subsys
;
8102 cmd
= ssh
->cfg
.remote_cmd_ptr
;
8103 if (!cmd
) cmd
= ssh
->cfg
.remote_cmd
;
8106 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
8107 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
8109 ssh2_pkt_addstring(s
->pktout
, "subsystem");
8110 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
8111 ssh2_pkt_addstring(s
->pktout
, cmd
);
8113 ssh2_pkt_addstring(s
->pktout
, "exec");
8114 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
8115 ssh2_pkt_addstring(s
->pktout
, cmd
);
8117 ssh2_pkt_addstring(s
->pktout
, "shell");
8118 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
8120 ssh2_pkt_send(ssh
, s
->pktout
);
8122 crWaitUntilV(pktin
);
8124 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
8125 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
8126 bombout(("Unexpected response to shell/command request:"
8127 " packet type %d", pktin
->type
));
8131 * We failed to start the command. If this is the
8132 * fallback command, we really are finished; if it's
8133 * not, and if the fallback command exists, try falling
8134 * back to it before complaining.
8136 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
8137 logevent("Primary command failed; attempting fallback");
8138 ssh
->fallback_cmd
= TRUE
;
8141 bombout(("Server refused to start a shell/command"));
8144 logevent("Started a shell/command");
8149 ssh
->state
= SSH_STATE_SESSION
;
8150 if (ssh
->size_needed
)
8151 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
8152 if (ssh
->eof_needed
)
8153 ssh_special(ssh
, TS_EOF
);
8159 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
8164 s
->try_send
= FALSE
;
8168 * _All_ the connection-layer packets we expect to
8169 * receive are now handled by the dispatch table.
8170 * Anything that reaches here must be bogus.
8173 bombout(("Strange packet received: type %d", pktin
->type
));
8175 } else if (ssh
->mainchan
) {
8177 * We have spare data. Add it to the channel buffer.
8179 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
8184 struct ssh_channel
*c
;
8186 * Try to send data on all channels if we can.
8188 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++)
8189 ssh2_try_send_and_unthrottle(c
);
8197 * Handlers for SSH-2 messages that might arrive at any moment.
8199 static void ssh2_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
8201 /* log reason code in disconnect message */
8203 int nowlen
, reason
, msglen
;
8205 reason
= ssh_pkt_getuint32(pktin
);
8206 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
8208 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
8209 buf
= dupprintf("Received disconnect message (%s)",
8210 ssh2_disconnect_reasons
[reason
]);
8212 buf
= dupprintf("Received disconnect message (unknown"
8213 " type %d)", reason
);
8217 buf
= dupprintf("Disconnection message text: %n%.*s",
8218 &nowlen
, msglen
, msg
);
8220 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
8222 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
8223 ssh2_disconnect_reasons
[reason
] : "unknown",
8228 static void ssh2_msg_debug(Ssh ssh
, struct Packet
*pktin
)
8230 /* log the debug message */
8235 /* XXX maybe we should actually take notice of this */
8236 always_display
= ssh2_pkt_getbool(pktin
);
8237 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
8239 logeventf(ssh
, "Remote debug message: %.*s", msglen
, msg
);
8242 static void ssh2_msg_something_unimplemented(Ssh ssh
, struct Packet
*pktin
)
8244 struct Packet
*pktout
;
8245 pktout
= ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
8246 ssh2_pkt_adduint32(pktout
, pktin
->sequence
);
8248 * UNIMPLEMENTED messages MUST appear in the same order as the
8249 * messages they respond to. Hence, never queue them.
8251 ssh2_pkt_send_noqueue(ssh
, pktout
);
8255 * Handle the top-level SSH-2 protocol.
8257 static void ssh2_protocol_setup(Ssh ssh
)
8262 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
8264 for (i
= 0; i
< 256; i
++)
8265 ssh
->packet_dispatch
[i
] = ssh2_msg_something_unimplemented
;
8268 * Any message we actually understand, we set to NULL so that
8269 * the coroutines will get it.
8271 ssh
->packet_dispatch
[SSH2_MSG_UNIMPLEMENTED
] = NULL
;
8272 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_REQUEST
] = NULL
;
8273 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_ACCEPT
] = NULL
;
8274 ssh
->packet_dispatch
[SSH2_MSG_KEXINIT
] = NULL
;
8275 ssh
->packet_dispatch
[SSH2_MSG_NEWKEYS
] = NULL
;
8276 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_INIT
] = NULL
;
8277 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_REPLY
] = NULL
;
8278 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
8279 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
8280 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_INIT
] = NULL
;
8281 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_REPLY
] = NULL
;
8282 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_REQUEST
] = NULL
;
8283 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_FAILURE
] = NULL
;
8284 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_SUCCESS
] = NULL
;
8285 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
8286 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_PK_OK
] = NULL
;
8287 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
8288 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
8289 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_INFO_RESPONSE
] = NULL
;
8290 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] = NULL
;
8291 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_SUCCESS
] = NULL
;
8292 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_FAILURE
] = NULL
;
8293 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] = NULL
;
8294 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] = NULL
;
8295 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] = NULL
;
8296 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] = NULL
;
8297 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] = NULL
;
8298 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] = NULL
;
8299 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = NULL
;
8300 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = NULL
;
8301 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] = NULL
;
8302 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_SUCCESS
] = NULL
;
8303 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_FAILURE
] = NULL
;
8306 * These special message types we install handlers for.
8308 ssh
->packet_dispatch
[SSH2_MSG_DISCONNECT
] = ssh2_msg_disconnect
;
8309 ssh
->packet_dispatch
[SSH2_MSG_IGNORE
] = ssh_msg_ignore
; /* shared with SSH-1 */
8310 ssh
->packet_dispatch
[SSH2_MSG_DEBUG
] = ssh2_msg_debug
;
8313 static void ssh2_timer(void *ctx
, long now
)
8317 if (ssh
->state
== SSH_STATE_CLOSED
)
8320 if (!ssh
->kex_in_progress
&& ssh
->cfg
.ssh_rekey_time
!= 0 &&
8321 now
- ssh
->next_rekey
>= 0) {
8322 do_ssh2_transport(ssh
, "timeout", -1, NULL
);
8326 static void ssh2_protocol(Ssh ssh
, void *vin
, int inlen
,
8327 struct Packet
*pktin
)
8329 unsigned char *in
= (unsigned char *)vin
;
8330 if (ssh
->state
== SSH_STATE_CLOSED
)
8334 ssh
->incoming_data_size
+= pktin
->encrypted_len
;
8335 if (!ssh
->kex_in_progress
&&
8336 ssh
->max_data_size
!= 0 &&
8337 ssh
->incoming_data_size
> ssh
->max_data_size
)
8338 do_ssh2_transport(ssh
, "too much data received", -1, NULL
);
8341 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
8342 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
8346 if (!ssh
->protocol_initial_phase_done
||
8347 (pktin
&& pktin
->type
>= 20 && pktin
->type
< 50)) {
8348 if (do_ssh2_transport(ssh
, in
, inlen
, pktin
) &&
8349 !ssh
->protocol_initial_phase_done
) {
8350 ssh
->protocol_initial_phase_done
= TRUE
;
8352 * Allow authconn to initialise itself.
8354 do_ssh2_authconn(ssh
, NULL
, 0, NULL
);
8357 do_ssh2_authconn(ssh
, in
, inlen
, pktin
);
8362 * Called to set up the connection.
8364 * Returns an error message, or NULL on success.
8366 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
8368 char *host
, int port
, char **realhost
, int nodelay
,
8374 ssh
= snew(struct ssh_tag
);
8375 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
8376 ssh
->version
= 0; /* when not ready yet */
8379 ssh
->v1_cipher_ctx
= NULL
;
8380 ssh
->crcda_ctx
= NULL
;
8381 ssh
->cscipher
= NULL
;
8382 ssh
->cs_cipher_ctx
= NULL
;
8383 ssh
->sccipher
= NULL
;
8384 ssh
->sc_cipher_ctx
= NULL
;
8386 ssh
->cs_mac_ctx
= NULL
;
8388 ssh
->sc_mac_ctx
= NULL
;
8390 ssh
->cs_comp_ctx
= NULL
;
8392 ssh
->sc_comp_ctx
= NULL
;
8394 ssh
->kex_ctx
= NULL
;
8395 ssh
->hostkey
= NULL
;
8397 ssh
->close_expected
= FALSE
;
8398 ssh
->clean_exit
= FALSE
;
8399 ssh
->state
= SSH_STATE_PREPACKET
;
8400 ssh
->size_needed
= FALSE
;
8401 ssh
->eof_needed
= FALSE
;
8404 ssh
->deferred_send_data
= NULL
;
8405 ssh
->deferred_len
= 0;
8406 ssh
->deferred_size
= 0;
8407 ssh
->fallback_cmd
= 0;
8409 ssh
->x11auth
= NULL
;
8410 ssh
->v1_compressing
= FALSE
;
8411 ssh
->v2_outgoing_sequence
= 0;
8412 ssh
->ssh1_rdpkt_crstate
= 0;
8413 ssh
->ssh2_rdpkt_crstate
= 0;
8414 ssh
->do_ssh_init_crstate
= 0;
8415 ssh
->ssh_gotdata_crstate
= 0;
8416 ssh
->do_ssh1_connection_crstate
= 0;
8417 ssh
->do_ssh1_login_crstate
= 0;
8418 ssh
->do_ssh2_transport_crstate
= 0;
8419 ssh
->do_ssh2_authconn_crstate
= 0;
8420 ssh
->do_ssh_init_state
= NULL
;
8421 ssh
->do_ssh1_login_state
= NULL
;
8422 ssh
->do_ssh2_transport_state
= NULL
;
8423 ssh
->do_ssh2_authconn_state
= NULL
;
8426 ssh
->mainchan
= NULL
;
8427 ssh
->throttled_all
= 0;
8428 ssh
->v1_stdout_throttling
= 0;
8430 ssh
->queuelen
= ssh
->queuesize
= 0;
8431 ssh
->queueing
= FALSE
;
8432 ssh
->qhead
= ssh
->qtail
= NULL
;
8433 ssh
->deferred_rekey_reason
= NULL
;
8434 bufchain_init(&ssh
->queued_incoming_data
);
8435 ssh
->frozen
= FALSE
;
8437 *backend_handle
= ssh
;
8440 if (crypto_startup() == 0)
8441 return "Microsoft high encryption pack not installed!";
8444 ssh
->frontend
= frontend_handle
;
8445 ssh
->term_width
= ssh
->cfg
.width
;
8446 ssh
->term_height
= ssh
->cfg
.height
;
8448 ssh
->channels
= NULL
;
8449 ssh
->rportfwds
= NULL
;
8450 ssh
->portfwds
= NULL
;
8455 ssh
->v1_throttle_count
= 0;
8456 ssh
->overall_bufsize
= 0;
8457 ssh
->fallback_cmd
= 0;
8459 ssh
->protocol
= NULL
;
8461 ssh
->protocol_initial_phase_done
= FALSE
;
8465 ssh
->incoming_data_size
= ssh
->outgoing_data_size
=
8466 ssh
->deferred_data_size
= 0L;
8467 ssh
->max_data_size
= parse_blocksize(ssh
->cfg
.ssh_rekey_data
);
8468 ssh
->kex_in_progress
= FALSE
;
8470 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
8479 static void ssh_free(void *handle
)
8481 Ssh ssh
= (Ssh
) handle
;
8482 struct ssh_channel
*c
;
8483 struct ssh_rportfwd
*pf
;
8485 if (ssh
->v1_cipher_ctx
)
8486 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
8487 if (ssh
->cs_cipher_ctx
)
8488 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
8489 if (ssh
->sc_cipher_ctx
)
8490 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
8491 if (ssh
->cs_mac_ctx
)
8492 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
8493 if (ssh
->sc_mac_ctx
)
8494 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
8495 if (ssh
->cs_comp_ctx
) {
8497 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
8499 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
8501 if (ssh
->sc_comp_ctx
) {
8503 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
8505 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
8508 dh_cleanup(ssh
->kex_ctx
);
8509 sfree(ssh
->savedhost
);
8511 while (ssh
->queuelen
-- > 0)
8512 ssh_free_packet(ssh
->queue
[ssh
->queuelen
]);
8515 while (ssh
->qhead
) {
8516 struct queued_handler
*qh
= ssh
->qhead
;
8517 ssh
->qhead
= qh
->next
;
8520 ssh
->qhead
= ssh
->qtail
= NULL
;
8522 if (ssh
->channels
) {
8523 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
8526 if (c
->u
.x11
.s
!= NULL
)
8527 x11_close(c
->u
.x11
.s
);
8530 if (c
->u
.pfd
.s
!= NULL
)
8531 pfd_close(c
->u
.pfd
.s
);
8536 freetree234(ssh
->channels
);
8537 ssh
->channels
= NULL
;
8540 if (ssh
->rportfwds
) {
8541 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
8543 freetree234(ssh
->rportfwds
);
8544 ssh
->rportfwds
= NULL
;
8546 sfree(ssh
->deferred_send_data
);
8548 x11_free_auth(ssh
->x11auth
);
8549 sfree(ssh
->do_ssh_init_state
);
8550 sfree(ssh
->do_ssh1_login_state
);
8551 sfree(ssh
->do_ssh2_transport_state
);
8552 sfree(ssh
->do_ssh2_authconn_state
);
8555 if (ssh
->crcda_ctx
) {
8556 crcda_free_context(ssh
->crcda_ctx
);
8557 ssh
->crcda_ctx
= NULL
;
8560 ssh_do_close(ssh
, TRUE
);
8561 expire_timer_context(ssh
);
8563 pinger_free(ssh
->pinger
);
8564 bufchain_clear(&ssh
->queued_incoming_data
);
8571 * Reconfigure the SSH backend.
8573 static void ssh_reconfig(void *handle
, Config
*cfg
)
8575 Ssh ssh
= (Ssh
) handle
;
8576 char *rekeying
= NULL
, rekey_mandatory
= FALSE
;
8577 unsigned long old_max_data_size
;
8579 pinger_reconfig(ssh
->pinger
, &ssh
->cfg
, cfg
);
8581 ssh_setup_portfwd(ssh
, cfg
);
8583 if (ssh
->cfg
.ssh_rekey_time
!= cfg
->ssh_rekey_time
&&
8584 cfg
->ssh_rekey_time
!= 0) {
8585 long new_next
= ssh
->last_rekey
+ cfg
->ssh_rekey_time
*60*TICKSPERSEC
;
8586 long now
= GETTICKCOUNT();
8588 if (new_next
- now
< 0) {
8589 rekeying
= "timeout shortened";
8591 ssh
->next_rekey
= schedule_timer(new_next
- now
, ssh2_timer
, ssh
);
8595 old_max_data_size
= ssh
->max_data_size
;
8596 ssh
->max_data_size
= parse_blocksize(cfg
->ssh_rekey_data
);
8597 if (old_max_data_size
!= ssh
->max_data_size
&&
8598 ssh
->max_data_size
!= 0) {
8599 if (ssh
->outgoing_data_size
> ssh
->max_data_size
||
8600 ssh
->incoming_data_size
> ssh
->max_data_size
)
8601 rekeying
= "data limit lowered";
8604 if (ssh
->cfg
.compression
!= cfg
->compression
) {
8605 rekeying
= "compression setting changed";
8606 rekey_mandatory
= TRUE
;
8609 if (ssh
->cfg
.ssh2_des_cbc
!= cfg
->ssh2_des_cbc
||
8610 memcmp(ssh
->cfg
.ssh_cipherlist
, cfg
->ssh_cipherlist
,
8611 sizeof(ssh
->cfg
.ssh_cipherlist
))) {
8612 rekeying
= "cipher settings changed";
8613 rekey_mandatory
= TRUE
;
8616 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
8619 if (!ssh
->kex_in_progress
) {
8620 do_ssh2_transport(ssh
, rekeying
, -1, NULL
);
8621 } else if (rekey_mandatory
) {
8622 ssh
->deferred_rekey_reason
= rekeying
;
8628 * Called to send data down the SSH connection.
8630 static int ssh_send(void *handle
, char *buf
, int len
)
8632 Ssh ssh
= (Ssh
) handle
;
8634 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
8637 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
8639 return ssh_sendbuffer(ssh
);
8643 * Called to query the current amount of buffered stdin data.
8645 static int ssh_sendbuffer(void *handle
)
8647 Ssh ssh
= (Ssh
) handle
;
8650 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
8654 * If the SSH socket itself has backed up, add the total backup
8655 * size on that to any individual buffer on the stdin channel.
8658 if (ssh
->throttled_all
)
8659 override_value
= ssh
->overall_bufsize
;
8661 if (ssh
->version
== 1) {
8662 return override_value
;
8663 } else if (ssh
->version
== 2) {
8664 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
8665 return override_value
;
8667 return (override_value
+
8668 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
8675 * Called to set the size of the window from SSH's POV.
8677 static void ssh_size(void *handle
, int width
, int height
)
8679 Ssh ssh
= (Ssh
) handle
;
8680 struct Packet
*pktout
;
8682 ssh
->term_width
= width
;
8683 ssh
->term_height
= height
;
8685 switch (ssh
->state
) {
8686 case SSH_STATE_BEFORE_SIZE
:
8687 case SSH_STATE_PREPACKET
:
8688 case SSH_STATE_CLOSED
:
8689 break; /* do nothing */
8690 case SSH_STATE_INTERMED
:
8691 ssh
->size_needed
= TRUE
; /* buffer for later */
8693 case SSH_STATE_SESSION
:
8694 if (!ssh
->cfg
.nopty
) {
8695 if (ssh
->version
== 1) {
8696 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
8697 PKT_INT
, ssh
->term_height
,
8698 PKT_INT
, ssh
->term_width
,
8699 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
8700 } else if (ssh
->mainchan
) {
8701 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
8702 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8703 ssh2_pkt_addstring(pktout
, "window-change");
8704 ssh2_pkt_addbool(pktout
, 0);
8705 ssh2_pkt_adduint32(pktout
, ssh
->term_width
);
8706 ssh2_pkt_adduint32(pktout
, ssh
->term_height
);
8707 ssh2_pkt_adduint32(pktout
, 0);
8708 ssh2_pkt_adduint32(pktout
, 0);
8709 ssh2_pkt_send(ssh
, pktout
);
8717 * Return a list of the special codes that make sense in this
8720 static const struct telnet_special
*ssh_get_specials(void *handle
)
8722 static const struct telnet_special ssh1_ignore_special
[] = {
8723 {"IGNORE message", TS_NOP
}
8725 static const struct telnet_special ssh2_transport_specials
[] = {
8726 {"IGNORE message", TS_NOP
},
8727 {"Repeat key exchange", TS_REKEY
},
8729 static const struct telnet_special ssh2_session_specials
[] = {
8732 /* These are the signal names defined by draft-ietf-secsh-connect-23.
8733 * They include all the ISO C signals, but are a subset of the POSIX
8734 * required signals. */
8735 {"SIGINT (Interrupt)", TS_SIGINT
},
8736 {"SIGTERM (Terminate)", TS_SIGTERM
},
8737 {"SIGKILL (Kill)", TS_SIGKILL
},
8738 {"SIGQUIT (Quit)", TS_SIGQUIT
},
8739 {"SIGHUP (Hangup)", TS_SIGHUP
},
8740 {"More signals", TS_SUBMENU
},
8741 {"SIGABRT", TS_SIGABRT
}, {"SIGALRM", TS_SIGALRM
},
8742 {"SIGFPE", TS_SIGFPE
}, {"SIGILL", TS_SIGILL
},
8743 {"SIGPIPE", TS_SIGPIPE
}, {"SIGSEGV", TS_SIGSEGV
},
8744 {"SIGUSR1", TS_SIGUSR1
}, {"SIGUSR2", TS_SIGUSR2
},
8747 static const struct telnet_special specials_end
[] = {
8750 /* XXX review this length for any changes: */
8751 static struct telnet_special ssh_specials
[lenof(ssh2_transport_specials
) +
8752 lenof(ssh2_session_specials
) +
8753 lenof(specials_end
)];
8754 Ssh ssh
= (Ssh
) handle
;
8756 #define ADD_SPECIALS(name) \
8758 assert((i + lenof(name)) <= lenof(ssh_specials)); \
8759 memcpy(&ssh_specials[i], name, sizeof name); \
8763 if (ssh
->version
== 1) {
8764 /* Don't bother offering IGNORE if we've decided the remote
8765 * won't cope with it, since we wouldn't bother sending it if
8767 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
8768 ADD_SPECIALS(ssh1_ignore_special
);
8769 } else if (ssh
->version
== 2) {
8770 ADD_SPECIALS(ssh2_transport_specials
);
8772 ADD_SPECIALS(ssh2_session_specials
);
8773 } /* else we're not ready yet */
8776 ADD_SPECIALS(specials_end
);
8777 return ssh_specials
;
8785 * Send special codes. TS_EOF is useful for `plink', so you
8786 * can send an EOF and collect resulting output (e.g. `plink
8789 static void ssh_special(void *handle
, Telnet_Special code
)
8791 Ssh ssh
= (Ssh
) handle
;
8792 struct Packet
*pktout
;
8794 if (code
== TS_EOF
) {
8795 if (ssh
->state
!= SSH_STATE_SESSION
) {
8797 * Buffer the EOF in case we are pre-SESSION, so we can
8798 * send it as soon as we reach SESSION.
8801 ssh
->eof_needed
= TRUE
;
8804 if (ssh
->version
== 1) {
8805 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
8806 } else if (ssh
->mainchan
) {
8807 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
8808 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8809 ssh2_pkt_send(ssh
, pktout
);
8810 ssh
->send_ok
= 0; /* now stop trying to read from stdin */
8812 logevent("Sent EOF message");
8813 } else if (code
== TS_PING
|| code
== TS_NOP
) {
8814 if (ssh
->state
== SSH_STATE_CLOSED
8815 || ssh
->state
== SSH_STATE_PREPACKET
) return;
8816 if (ssh
->version
== 1) {
8817 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
8818 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
8820 pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
8821 ssh2_pkt_addstring_start(pktout
);
8822 ssh2_pkt_send_noqueue(ssh
, pktout
);
8824 } else if (code
== TS_REKEY
) {
8825 if (!ssh
->kex_in_progress
&& ssh
->version
== 2) {
8826 do_ssh2_transport(ssh
, "at user request", -1, NULL
);
8828 } else if (code
== TS_BRK
) {
8829 if (ssh
->state
== SSH_STATE_CLOSED
8830 || ssh
->state
== SSH_STATE_PREPACKET
) return;
8831 if (ssh
->version
== 1) {
8832 logevent("Unable to send BREAK signal in SSH-1");
8833 } else if (ssh
->mainchan
) {
8834 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
8835 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8836 ssh2_pkt_addstring(pktout
, "break");
8837 ssh2_pkt_addbool(pktout
, 0);
8838 ssh2_pkt_adduint32(pktout
, 0); /* default break length */
8839 ssh2_pkt_send(ssh
, pktout
);
8842 /* Is is a POSIX signal? */
8843 char *signame
= NULL
;
8844 if (code
== TS_SIGABRT
) signame
= "ABRT";
8845 if (code
== TS_SIGALRM
) signame
= "ALRM";
8846 if (code
== TS_SIGFPE
) signame
= "FPE";
8847 if (code
== TS_SIGHUP
) signame
= "HUP";
8848 if (code
== TS_SIGILL
) signame
= "ILL";
8849 if (code
== TS_SIGINT
) signame
= "INT";
8850 if (code
== TS_SIGKILL
) signame
= "KILL";
8851 if (code
== TS_SIGPIPE
) signame
= "PIPE";
8852 if (code
== TS_SIGQUIT
) signame
= "QUIT";
8853 if (code
== TS_SIGSEGV
) signame
= "SEGV";
8854 if (code
== TS_SIGTERM
) signame
= "TERM";
8855 if (code
== TS_SIGUSR1
) signame
= "USR1";
8856 if (code
== TS_SIGUSR2
) signame
= "USR2";
8857 /* The SSH-2 protocol does in principle support arbitrary named
8858 * signals, including signame@domain, but we don't support those. */
8860 /* It's a signal. */
8861 if (ssh
->version
== 2 && ssh
->mainchan
) {
8862 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
8863 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8864 ssh2_pkt_addstring(pktout
, "signal");
8865 ssh2_pkt_addbool(pktout
, 0);
8866 ssh2_pkt_addstring(pktout
, signame
);
8867 ssh2_pkt_send(ssh
, pktout
);
8868 logeventf(ssh
, "Sent signal SIG%s", signame
);
8871 /* Never heard of it. Do nothing */
8876 void *new_sock_channel(void *handle
, Socket s
)
8878 Ssh ssh
= (Ssh
) handle
;
8879 struct ssh_channel
*c
;
8880 c
= snew(struct ssh_channel
);
8885 c
->localid
= alloc_channel_id(ssh
);
8887 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
8889 bufchain_init(&c
->v
.v2
.outbuffer
);
8890 add234(ssh
->channels
, c
);
8896 * This is called when stdout/stderr (the entity to which
8897 * from_backend sends data) manages to clear some backlog.
8899 static void ssh_unthrottle(void *handle
, int bufsize
)
8901 Ssh ssh
= (Ssh
) handle
;
8902 if (ssh
->version
== 1) {
8903 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
8904 ssh
->v1_stdout_throttling
= 0;
8905 ssh1_throttle(ssh
, -1);
8908 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
8912 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
8914 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
8916 struct Packet
*pktout
;
8918 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
8920 if (ssh
->version
== 1) {
8921 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
8922 PKT_INT
, c
->localid
,
8925 /* PKT_STR, <org:orgport>, */
8928 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
8929 ssh2_pkt_addstring(pktout
, "direct-tcpip");
8930 ssh2_pkt_adduint32(pktout
, c
->localid
);
8931 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
8932 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);/* our window size */
8933 ssh2_pkt_adduint32(pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
8934 ssh2_pkt_addstring(pktout
, hostname
);
8935 ssh2_pkt_adduint32(pktout
, port
);
8937 * We make up values for the originator data; partly it's
8938 * too much hassle to keep track, and partly I'm not
8939 * convinced the server should be told details like that
8940 * about my local network configuration.
8941 * The "originator IP address" is syntactically a numeric
8942 * IP address, and some servers (e.g., Tectia) get upset
8943 * if it doesn't match this syntax.
8945 ssh2_pkt_addstring(pktout
, "0.0.0.0");
8946 ssh2_pkt_adduint32(pktout
, 0);
8947 ssh2_pkt_send(ssh
, pktout
);
8951 static int ssh_connected(void *handle
)
8953 Ssh ssh
= (Ssh
) handle
;
8954 return ssh
->s
!= NULL
;
8957 static int ssh_sendok(void *handle
)
8959 Ssh ssh
= (Ssh
) handle
;
8960 return ssh
->send_ok
;
8963 static int ssh_ldisc(void *handle
, int option
)
8965 Ssh ssh
= (Ssh
) handle
;
8966 if (option
== LD_ECHO
)
8967 return ssh
->echoing
;
8968 if (option
== LD_EDIT
)
8969 return ssh
->editing
;
8973 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
8975 Ssh ssh
= (Ssh
) handle
;
8979 static void ssh_provide_logctx(void *handle
, void *logctx
)
8981 Ssh ssh
= (Ssh
) handle
;
8982 ssh
->logctx
= logctx
;
8985 static int ssh_return_exitcode(void *handle
)
8987 Ssh ssh
= (Ssh
) handle
;
8991 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: INT_MAX
);
8995 * cfg_info for SSH is the currently running version of the
8996 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
8998 static int ssh_cfg_info(void *handle
)
9000 Ssh ssh
= (Ssh
) handle
;
9001 return ssh
->version
;
9005 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
9006 * that fails. This variable is the means by which scp.c can reach
9007 * into the SSH code and find out which one it got.
9009 extern int ssh_fallback_cmd(void *handle
)
9011 Ssh ssh
= (Ssh
) handle
;
9012 return ssh
->fallback_cmd
;
9015 Backend ssh_backend
= {
9025 ssh_return_exitcode
,