17 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
18 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
19 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
20 #define SSH1_CMSG_USER 4 /* 0x4 */
21 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
22 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
23 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
24 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
25 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
26 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
27 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
28 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
29 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
30 #define SSH1_SMSG_FAILURE 15 /* 0xf */
31 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
32 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
33 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
34 #define SSH1_CMSG_EOF 19 /* 0x13 */
35 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
36 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
37 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
38 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
39 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
40 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
41 #define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
42 #define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
43 #define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
44 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
45 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
46 #define SSH1_MSG_IGNORE 32 /* 0x20 */
47 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
48 #define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
49 #define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
50 #define SSH1_MSG_DEBUG 36 /* 0x24 */
51 #define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
52 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
53 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
54 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
55 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
56 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
57 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
59 #define SSH1_AUTH_TIS 5 /* 0x5 */
60 #define SSH1_AUTH_CCARD 16 /* 0x10 */
62 #define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
63 /* Mask for protoflags we will echo back to server if seen */
64 #define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
66 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
67 #define SSH2_MSG_IGNORE 2 /* 0x2 */
68 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
69 #define SSH2_MSG_DEBUG 4 /* 0x4 */
70 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
71 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
72 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
73 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
74 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
75 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
76 #define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
77 #define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
78 #define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
79 #define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
80 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
81 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
82 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
83 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
84 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
85 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
86 #define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
87 #define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
88 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
89 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
90 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
91 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
92 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
93 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
94 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
95 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
96 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
97 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
98 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
99 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
100 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
101 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
104 * Packet type contexts, so that ssh2_pkt_type can correctly decode
105 * the ambiguous type numbers back into the correct type strings.
107 #define SSH2_PKTCTX_DHGROUP 0x0001
108 #define SSH2_PKTCTX_DHGEX 0x0002
109 #define SSH2_PKTCTX_KEX_MASK 0x000F
110 #define SSH2_PKTCTX_PUBLICKEY 0x0010
111 #define SSH2_PKTCTX_PASSWORD 0x0020
112 #define SSH2_PKTCTX_KBDINTER 0x0040
113 #define SSH2_PKTCTX_AUTH_MASK 0x00F0
115 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
116 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
117 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
118 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
119 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
120 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
121 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
122 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
123 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
124 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
125 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
126 #define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
127 #define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
128 #define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
129 #define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
131 static const char *const ssh2_disconnect_reasons
[] = {
133 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
134 "SSH_DISCONNECT_PROTOCOL_ERROR",
135 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
136 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
137 "SSH_DISCONNECT_MAC_ERROR",
138 "SSH_DISCONNECT_COMPRESSION_ERROR",
139 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
140 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
141 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
142 "SSH_DISCONNECT_CONNECTION_LOST",
143 "SSH_DISCONNECT_BY_APPLICATION",
144 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
145 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
146 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
147 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
150 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
151 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
152 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
153 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
155 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
158 * Various remote-bug flags.
160 #define BUG_CHOKES_ON_SSH1_IGNORE 1
161 #define BUG_SSH2_HMAC 2
162 #define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
163 #define BUG_CHOKES_ON_RSA 8
164 #define BUG_SSH2_RSA_PADDING 16
165 #define BUG_SSH2_DERIVEKEY 32
166 #define BUG_SSH2_REKEY 64
167 #define BUG_SSH2_PK_SESSIONID 128
170 * Codes for terminal modes.
171 * Most of these are the same in SSH-1 and SSH-2.
172 * This list is derived from draft-ietf-secsh-connect-25 and
175 static const struct {
176 const char* const mode
;
178 enum { TTY_OP_CHAR
, TTY_OP_BOOL
} type
;
180 /* "V" prefix discarded for special characters relative to SSH specs */
181 { "INTR", 1, TTY_OP_CHAR
},
182 { "QUIT", 2, TTY_OP_CHAR
},
183 { "ERASE", 3, TTY_OP_CHAR
},
184 { "KILL", 4, TTY_OP_CHAR
},
185 { "EOF", 5, TTY_OP_CHAR
},
186 { "EOL", 6, TTY_OP_CHAR
},
187 { "EOL2", 7, TTY_OP_CHAR
},
188 { "START", 8, TTY_OP_CHAR
},
189 { "STOP", 9, TTY_OP_CHAR
},
190 { "SUSP", 10, TTY_OP_CHAR
},
191 { "DSUSP", 11, TTY_OP_CHAR
},
192 { "REPRINT", 12, TTY_OP_CHAR
},
193 { "WERASE", 13, TTY_OP_CHAR
},
194 { "LNEXT", 14, TTY_OP_CHAR
},
195 { "FLUSH", 15, TTY_OP_CHAR
},
196 { "SWTCH", 16, TTY_OP_CHAR
},
197 { "STATUS", 17, TTY_OP_CHAR
},
198 { "DISCARD", 18, TTY_OP_CHAR
},
199 { "IGNPAR", 30, TTY_OP_BOOL
},
200 { "PARMRK", 31, TTY_OP_BOOL
},
201 { "INPCK", 32, TTY_OP_BOOL
},
202 { "ISTRIP", 33, TTY_OP_BOOL
},
203 { "INLCR", 34, TTY_OP_BOOL
},
204 { "IGNCR", 35, TTY_OP_BOOL
},
205 { "ICRNL", 36, TTY_OP_BOOL
},
206 { "IUCLC", 37, TTY_OP_BOOL
},
207 { "IXON", 38, TTY_OP_BOOL
},
208 { "IXANY", 39, TTY_OP_BOOL
},
209 { "IXOFF", 40, TTY_OP_BOOL
},
210 { "IMAXBEL", 41, TTY_OP_BOOL
},
211 { "ISIG", 50, TTY_OP_BOOL
},
212 { "ICANON", 51, TTY_OP_BOOL
},
213 { "XCASE", 52, TTY_OP_BOOL
},
214 { "ECHO", 53, TTY_OP_BOOL
},
215 { "ECHOE", 54, TTY_OP_BOOL
},
216 { "ECHOK", 55, TTY_OP_BOOL
},
217 { "ECHONL", 56, TTY_OP_BOOL
},
218 { "NOFLSH", 57, TTY_OP_BOOL
},
219 { "TOSTOP", 58, TTY_OP_BOOL
},
220 { "IEXTEN", 59, TTY_OP_BOOL
},
221 { "ECHOCTL", 60, TTY_OP_BOOL
},
222 { "ECHOKE", 61, TTY_OP_BOOL
},
223 { "PENDIN", 62, TTY_OP_BOOL
}, /* XXX is this a real mode? */
224 { "OPOST", 70, TTY_OP_BOOL
},
225 { "OLCUC", 71, TTY_OP_BOOL
},
226 { "ONLCR", 72, TTY_OP_BOOL
},
227 { "OCRNL", 73, TTY_OP_BOOL
},
228 { "ONOCR", 74, TTY_OP_BOOL
},
229 { "ONLRET", 75, TTY_OP_BOOL
},
230 { "CS7", 90, TTY_OP_BOOL
},
231 { "CS8", 91, TTY_OP_BOOL
},
232 { "PARENB", 92, TTY_OP_BOOL
},
233 { "PARODD", 93, TTY_OP_BOOL
}
236 /* Miscellaneous other tty-related constants. */
237 #define SSH_TTY_OP_END 0
238 /* The opcodes for ISPEED/OSPEED differ between SSH-1 and SSH-2. */
239 #define SSH1_TTY_OP_ISPEED 192
240 #define SSH1_TTY_OP_OSPEED 193
241 #define SSH2_TTY_OP_ISPEED 128
242 #define SSH2_TTY_OP_OSPEED 129
244 /* Helper functions for parsing tty-related config. */
245 static unsigned int ssh_tty_parse_specchar(char *s
)
250 ret
= ctrlparse(s
, &next
);
251 if (!next
) ret
= s
[0];
253 ret
= 255; /* special value meaning "don't set" */
257 static unsigned int ssh_tty_parse_boolean(char *s
)
259 if (stricmp(s
, "yes") == 0 ||
260 stricmp(s
, "on") == 0 ||
261 stricmp(s
, "true") == 0 ||
262 stricmp(s
, "+") == 0)
264 else if (stricmp(s
, "no") == 0 ||
265 stricmp(s
, "off") == 0 ||
266 stricmp(s
, "false") == 0 ||
267 stricmp(s
, "-") == 0)
268 return 0; /* false */
270 return (atoi(s
) != 0);
273 #define translate(x) if (type == x) return #x
274 #define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
275 static char *ssh1_pkt_type(int type
)
277 translate(SSH1_MSG_DISCONNECT
);
278 translate(SSH1_SMSG_PUBLIC_KEY
);
279 translate(SSH1_CMSG_SESSION_KEY
);
280 translate(SSH1_CMSG_USER
);
281 translate(SSH1_CMSG_AUTH_RSA
);
282 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE
);
283 translate(SSH1_CMSG_AUTH_RSA_RESPONSE
);
284 translate(SSH1_CMSG_AUTH_PASSWORD
);
285 translate(SSH1_CMSG_REQUEST_PTY
);
286 translate(SSH1_CMSG_WINDOW_SIZE
);
287 translate(SSH1_CMSG_EXEC_SHELL
);
288 translate(SSH1_CMSG_EXEC_CMD
);
289 translate(SSH1_SMSG_SUCCESS
);
290 translate(SSH1_SMSG_FAILURE
);
291 translate(SSH1_CMSG_STDIN_DATA
);
292 translate(SSH1_SMSG_STDOUT_DATA
);
293 translate(SSH1_SMSG_STDERR_DATA
);
294 translate(SSH1_CMSG_EOF
);
295 translate(SSH1_SMSG_EXIT_STATUS
);
296 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
);
297 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE
);
298 translate(SSH1_MSG_CHANNEL_DATA
);
299 translate(SSH1_MSG_CHANNEL_CLOSE
);
300 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
);
301 translate(SSH1_SMSG_X11_OPEN
);
302 translate(SSH1_CMSG_PORT_FORWARD_REQUEST
);
303 translate(SSH1_MSG_PORT_OPEN
);
304 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING
);
305 translate(SSH1_SMSG_AGENT_OPEN
);
306 translate(SSH1_MSG_IGNORE
);
307 translate(SSH1_CMSG_EXIT_CONFIRMATION
);
308 translate(SSH1_CMSG_X11_REQUEST_FORWARDING
);
309 translate(SSH1_CMSG_AUTH_RHOSTS_RSA
);
310 translate(SSH1_MSG_DEBUG
);
311 translate(SSH1_CMSG_REQUEST_COMPRESSION
);
312 translate(SSH1_CMSG_AUTH_TIS
);
313 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE
);
314 translate(SSH1_CMSG_AUTH_TIS_RESPONSE
);
315 translate(SSH1_CMSG_AUTH_CCARD
);
316 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE
);
317 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE
);
320 static char *ssh2_pkt_type(int pkt_ctx
, int type
)
322 translate(SSH2_MSG_DISCONNECT
);
323 translate(SSH2_MSG_IGNORE
);
324 translate(SSH2_MSG_UNIMPLEMENTED
);
325 translate(SSH2_MSG_DEBUG
);
326 translate(SSH2_MSG_SERVICE_REQUEST
);
327 translate(SSH2_MSG_SERVICE_ACCEPT
);
328 translate(SSH2_MSG_KEXINIT
);
329 translate(SSH2_MSG_NEWKEYS
);
330 translatec(SSH2_MSG_KEXDH_INIT
, SSH2_PKTCTX_DHGROUP
);
331 translatec(SSH2_MSG_KEXDH_REPLY
, SSH2_PKTCTX_DHGROUP
);
332 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST
, SSH2_PKTCTX_DHGEX
);
333 translatec(SSH2_MSG_KEX_DH_GEX_GROUP
, SSH2_PKTCTX_DHGEX
);
334 translatec(SSH2_MSG_KEX_DH_GEX_INIT
, SSH2_PKTCTX_DHGEX
);
335 translatec(SSH2_MSG_KEX_DH_GEX_REPLY
, SSH2_PKTCTX_DHGEX
);
336 translate(SSH2_MSG_USERAUTH_REQUEST
);
337 translate(SSH2_MSG_USERAUTH_FAILURE
);
338 translate(SSH2_MSG_USERAUTH_SUCCESS
);
339 translate(SSH2_MSG_USERAUTH_BANNER
);
340 translatec(SSH2_MSG_USERAUTH_PK_OK
, SSH2_PKTCTX_PUBLICKEY
);
341 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
, SSH2_PKTCTX_PASSWORD
);
342 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST
, SSH2_PKTCTX_KBDINTER
);
343 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE
, SSH2_PKTCTX_KBDINTER
);
344 translate(SSH2_MSG_GLOBAL_REQUEST
);
345 translate(SSH2_MSG_REQUEST_SUCCESS
);
346 translate(SSH2_MSG_REQUEST_FAILURE
);
347 translate(SSH2_MSG_CHANNEL_OPEN
);
348 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
349 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
350 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
351 translate(SSH2_MSG_CHANNEL_DATA
);
352 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA
);
353 translate(SSH2_MSG_CHANNEL_EOF
);
354 translate(SSH2_MSG_CHANNEL_CLOSE
);
355 translate(SSH2_MSG_CHANNEL_REQUEST
);
356 translate(SSH2_MSG_CHANNEL_SUCCESS
);
357 translate(SSH2_MSG_CHANNEL_FAILURE
);
363 /* Enumeration values for fields in SSH-1 packets */
365 PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
,
366 /* These values are for communicating relevant semantics of
367 * fields to the packet logging code. */
368 PKTT_OTHER
, PKTT_PASSWORD
, PKTT_DATA
372 * Coroutine mechanics for the sillier bits of the code. If these
373 * macros look impenetrable to you, you might find it helpful to
376 * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
378 * which explains the theory behind these macros.
380 * In particular, if you are getting `case expression not constant'
381 * errors when building with MS Visual Studio, this is because MS's
382 * Edit and Continue debugging feature causes their compiler to
383 * violate ANSI C. To disable Edit and Continue debugging:
385 * - right-click ssh.c in the FileView
387 * - select the C/C++ tab and the General category
388 * - under `Debug info:', select anything _other_ than `Program
389 * Database for Edit and Continue'.
391 #define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
394 if (!ssh->t) ssh->t = snew(struct t); \
396 #define crFinish(z) } *crLine = 0; return (z); }
397 #define crFinishV } *crLine = 0; return; }
398 #define crReturn(z) \
400 *crLine =__LINE__; return (z); case __LINE__:;\
404 *crLine=__LINE__; return; case __LINE__:;\
406 #define crStop(z) do{ *crLine = 0; return (z); }while(0)
407 #define crStopV do{ *crLine = 0; return; }while(0)
408 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
409 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
411 typedef struct ssh_tag
*Ssh
;
414 static struct Packet
*ssh1_pkt_init(int pkt_type
);
415 static struct Packet
*ssh2_pkt_init(int pkt_type
);
416 static void ssh_pkt_ensure(struct Packet
*, int length
);
417 static void ssh_pkt_adddata(struct Packet
*, void *data
, int len
);
418 static void ssh_pkt_addbyte(struct Packet
*, unsigned char value
);
419 static void ssh2_pkt_addbool(struct Packet
*, unsigned char value
);
420 static void ssh_pkt_adduint32(struct Packet
*, unsigned long value
);
421 static void ssh_pkt_addstring_start(struct Packet
*);
422 static void ssh_pkt_addstring_str(struct Packet
*, char *data
);
423 static void ssh_pkt_addstring_data(struct Packet
*, char *data
, int len
);
424 static void ssh_pkt_addstring(struct Packet
*, char *data
);
425 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
);
426 static void ssh1_pkt_addmp(struct Packet
*, Bignum b
);
427 static void ssh2_pkt_addmp(struct Packet
*, Bignum b
);
428 static int ssh2_pkt_construct(Ssh
, struct Packet
*);
429 static void ssh2_pkt_send(Ssh
, struct Packet
*);
430 static void ssh2_pkt_send_noqueue(Ssh
, struct Packet
*);
431 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
432 struct Packet
*pktin
);
433 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
434 struct Packet
*pktin
);
437 * Buffer management constants. There are several of these for
438 * various different purposes:
440 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
441 * on a local data stream before we throttle the whole SSH
442 * connection (in SSH-1 only). Throttling the whole connection is
443 * pretty drastic so we set this high in the hope it won't
446 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
447 * on the SSH connection itself before we defensively throttle
448 * _all_ local data streams. This is pretty drastic too (though
449 * thankfully unlikely in SSH-2 since the window mechanism should
450 * ensure that the server never has any need to throttle its end
451 * of the connection), so we set this high as well.
453 * - OUR_V2_WINSIZE is the maximum window size we present on SSH-2
457 #define SSH1_BUFFER_LIMIT 32768
458 #define SSH_MAX_BACKLOG 32768
459 #define OUR_V2_WINSIZE 16384
460 #define OUR_V2_MAXPKT 0x4000UL
462 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
464 const static struct ssh_mac
*macs
[] = {
465 &ssh_hmac_sha1
, &ssh_hmac_md5
467 const static struct ssh_mac
*buggymacs
[] = {
468 &ssh_hmac_sha1_buggy
, &ssh_hmac_md5
471 static void *ssh_comp_none_init(void)
475 static void ssh_comp_none_cleanup(void *handle
)
478 static int ssh_comp_none_block(void *handle
, unsigned char *block
, int len
,
479 unsigned char **outblock
, int *outlen
)
483 static int ssh_comp_none_disable(void *handle
)
487 const static struct ssh_compress ssh_comp_none
= {
489 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
490 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
491 ssh_comp_none_disable
, NULL
493 extern const struct ssh_compress ssh_zlib
;
494 const static struct ssh_compress
*compressions
[] = {
495 &ssh_zlib
, &ssh_comp_none
498 enum { /* channel types */
503 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
507 * 2-3-4 tree storing channels.
510 Ssh ssh
; /* pointer back to main context */
511 unsigned remoteid
, localid
;
513 /* True if we opened this channel but server hasn't confirmed. */
516 * In SSH-1, this value contains four bits:
518 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
519 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
520 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
521 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
523 * A channel is completely finished with when all four bits are set.
527 struct ssh1_data_channel
{
530 struct ssh2_data_channel
{
532 unsigned remwindow
, remmaxpkt
;
537 struct ssh_agent_channel
{
538 unsigned char *message
;
539 unsigned char msglen
[4];
540 unsigned lensofar
, totallen
;
542 struct ssh_x11_channel
{
545 struct ssh_pfd_channel
{
552 * 2-3-4 tree storing remote->local port forwardings. SSH-1 and SSH-2
553 * use this structure in different ways, reflecting SSH-2's
554 * altogether saner approach to port forwarding.
556 * In SSH-1, you arrange a remote forwarding by sending the server
557 * the remote port number, and the local destination host:port.
558 * When a connection comes in, the server sends you back that
559 * host:port pair, and you connect to it. This is a ready-made
560 * security hole if you're not on the ball: a malicious server
561 * could send you back _any_ host:port pair, so if you trustingly
562 * connect to the address it gives you then you've just opened the
563 * entire inside of your corporate network just by connecting
564 * through it to a dodgy SSH server. Hence, we must store a list of
565 * host:port pairs we _are_ trying to forward to, and reject a
566 * connection request from the server if it's not in the list.
568 * In SSH-2, each side of the connection minds its own business and
569 * doesn't send unnecessary information to the other. You arrange a
570 * remote forwarding by sending the server just the remote port
571 * number. When a connection comes in, the server tells you which
572 * of its ports was connected to; and _you_ have to remember what
573 * local host:port pair went with that port number.
575 * Hence, in SSH-1 this structure is indexed by destination
576 * host:port pair, whereas in SSH-2 it is indexed by source port.
578 struct ssh_portfwd
; /* forward declaration */
580 struct ssh_rportfwd
{
581 unsigned sport
, dport
;
584 struct ssh_portfwd
*pfrec
;
586 #define free_rportfwd(pf) ( \
587 ((pf) ? (sfree((pf)->sportdesc)) : (void)0 ), sfree(pf) )
590 * Separately to the rportfwd tree (which is for looking up port
591 * open requests from the server), a tree of _these_ structures is
592 * used to keep track of all the currently open port forwardings,
593 * so that we can reconfigure in mid-session if the user requests
597 enum { DESTROY
, KEEP
, CREATE
} status
;
599 unsigned sport
, dport
;
602 struct ssh_rportfwd
*remote
;
606 #define free_portfwd(pf) ( \
607 ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr), \
608 sfree((pf)->sserv), sfree((pf)->dserv)) : (void)0 ), sfree(pf) )
611 long length
; /* length of `data' actually used */
612 long forcepad
; /* SSH-2: force padding to at least this length */
613 int type
; /* only used for incoming packets */
614 unsigned long sequence
; /* SSH-2 incoming sequence number */
615 unsigned char *data
; /* allocated storage */
616 unsigned char *body
; /* offset of payload within `data' */
617 long savedpos
; /* temporary index into `data' (for strings) */
618 long maxlen
; /* amount of storage allocated for `data' */
619 long encrypted_len
; /* for SSH-2 total-size counting */
622 * State associated with packet logging
626 struct logblank_t
*blanks
;
629 static void ssh1_protocol(Ssh ssh
, void *vin
, int inlen
,
630 struct Packet
*pktin
);
631 static void ssh2_protocol(Ssh ssh
, void *vin
, int inlen
,
632 struct Packet
*pktin
);
633 static void ssh1_protocol_setup(Ssh ssh
);
634 static void ssh2_protocol_setup(Ssh ssh
);
635 static void ssh_size(void *handle
, int width
, int height
);
636 static void ssh_special(void *handle
, Telnet_Special
);
637 static int ssh2_try_send(struct ssh_channel
*c
);
638 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
639 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
640 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
641 static int ssh_sendbuffer(void *handle
);
642 static int ssh_do_close(Ssh ssh
, int notify_exit
);
643 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
);
644 static int ssh2_pkt_getbool(struct Packet
*pkt
);
645 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
);
646 static void ssh2_timer(void *ctx
, long now
);
647 static int do_ssh2_transport(Ssh ssh
, void *vin
, int inlen
,
648 struct Packet
*pktin
);
650 struct rdpkt1_state_tag
{
651 long len
, pad
, biglen
, to_read
;
652 unsigned long realcrc
, gotcrc
;
656 struct Packet
*pktin
;
659 struct rdpkt2_state_tag
{
660 long len
, pad
, payload
, packetlen
, maclen
;
663 unsigned long incoming_sequence
;
664 struct Packet
*pktin
;
667 typedef void (*handler_fn_t
)(Ssh ssh
, struct Packet
*pktin
);
668 typedef void (*chandler_fn_t
)(Ssh ssh
, struct Packet
*pktin
, void *ctx
);
670 struct queued_handler
;
671 struct queued_handler
{
673 chandler_fn_t handler
;
675 struct queued_handler
*next
;
679 const struct plug_function_table
*fn
;
680 /* the above field _must_ be first in the structure */
690 unsigned char session_key
[32];
692 int v1_remote_protoflags
;
693 int v1_local_protoflags
;
694 int agentfwd_enabled
;
697 const struct ssh_cipher
*cipher
;
700 const struct ssh2_cipher
*cscipher
, *sccipher
;
701 void *cs_cipher_ctx
, *sc_cipher_ctx
;
702 const struct ssh_mac
*csmac
, *scmac
;
703 void *cs_mac_ctx
, *sc_mac_ctx
;
704 const struct ssh_compress
*cscomp
, *sccomp
;
705 void *cs_comp_ctx
, *sc_comp_ctx
;
706 const struct ssh_kex
*kex
;
707 const struct ssh_signkey
*hostkey
;
708 unsigned char v2_session_id
[20];
714 int echoing
, editing
;
718 int ospeed
, ispeed
; /* temporaries */
719 int term_width
, term_height
;
721 tree234
*channels
; /* indexed by local id */
722 struct ssh_channel
*mainchan
; /* primary session channel */
727 tree234
*rportfwds
, *portfwds
;
731 SSH_STATE_BEFORE_SIZE
,
737 int size_needed
, eof_needed
;
739 struct Packet
**queue
;
740 int queuelen
, queuesize
;
742 unsigned char *deferred_send_data
;
743 int deferred_len
, deferred_size
;
746 * Gross hack: pscp will try to start SFTP but fall back to
747 * scp1 if that fails. This variable is the means by which
748 * scp.c can reach into the SSH code and find out which one it
753 bufchain banner
; /* accumulates banners during do_ssh2_authconn */
755 * Used for username and password input.
757 char *userpass_input_buffer
;
758 int userpass_input_buflen
;
759 int userpass_input_bufpos
;
760 int userpass_input_echo
;
767 int v1_throttle_count
;
770 int v1_stdout_throttling
;
771 unsigned long v2_outgoing_sequence
;
773 int ssh1_rdpkt_crstate
;
774 int ssh2_rdpkt_crstate
;
775 int do_ssh_init_crstate
;
776 int ssh_gotdata_crstate
;
777 int do_ssh1_login_crstate
;
778 int do_ssh1_connection_crstate
;
779 int do_ssh2_transport_crstate
;
780 int do_ssh2_authconn_crstate
;
782 void *do_ssh_init_state
;
783 void *do_ssh1_login_state
;
784 void *do_ssh2_transport_state
;
785 void *do_ssh2_authconn_state
;
787 struct rdpkt1_state_tag rdpkt1_state
;
788 struct rdpkt2_state_tag rdpkt2_state
;
790 /* SSH-1 and SSH-2 use this for different things, but both use it */
791 int protocol_initial_phase_done
;
793 void (*protocol
) (Ssh ssh
, void *vin
, int inlen
,
795 struct Packet
*(*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
798 * We maintain a full _copy_ of a Config structure here, not
799 * merely a pointer to it. That way, when we're passed a new
800 * one for reconfiguration, we can check the differences and
801 * potentially reconfigure port forwardings etc in mid-session.
806 * Used to transfer data back from async callbacks.
808 void *agent_response
;
809 int agent_response_len
;
813 * The SSH connection can be set as `frozen', meaning we are
814 * not currently accepting incoming data from the network. This
815 * is slightly more serious than setting the _socket_ as
816 * frozen, because we may already have had data passed to us
817 * from the network which we need to delay processing until
818 * after the freeze is lifted, so we also need a bufchain to
822 bufchain queued_incoming_data
;
825 * Dispatch table for packet types that we may have to deal
828 handler_fn_t packet_dispatch
[256];
831 * Queues of one-off handler functions for success/failure
832 * indications from a request.
834 struct queued_handler
*qhead
, *qtail
;
837 * This module deals with sending keepalives.
842 * Track incoming and outgoing data sizes and time, for
845 unsigned long incoming_data_size
, outgoing_data_size
, deferred_data_size
;
846 unsigned long max_data_size
;
848 long next_rekey
, last_rekey
;
849 char *deferred_rekey_reason
; /* points to STATIC string; don't free */
852 #define logevent(s) logevent(ssh->frontend, s)
854 /* logevent, only printf-formatted. */
855 static void logeventf(Ssh ssh
, const char *fmt
, ...)
861 buf
= dupvprintf(fmt
, ap
);
867 #define bombout(msg) \
869 char *text = dupprintf msg; \
870 ssh_do_close(ssh, FALSE); \
872 connection_fatal(ssh->frontend, "%s", text); \
876 /* Functions to leave bits out of the SSH packet log file. */
878 static void dont_log_password(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
880 if (ssh
->cfg
.logomitpass
)
881 pkt
->logmode
= blanktype
;
884 static void dont_log_data(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
886 if (ssh
->cfg
.logomitdata
)
887 pkt
->logmode
= blanktype
;
890 static void end_log_omission(Ssh ssh
, struct Packet
*pkt
)
892 pkt
->logmode
= PKTLOG_EMIT
;
895 /* Helper function for common bits of parsing cfg.ttymodes. */
896 static void parse_ttymodes(Ssh ssh
, char *modes
,
897 void (*do_mode
)(void *data
, char *mode
, char *val
),
901 char *t
= strchr(modes
, '\t');
902 char *m
= snewn(t
-modes
+1, char);
904 strncpy(m
, modes
, t
-modes
);
907 val
= get_ttymode(ssh
->frontend
, m
);
911 do_mode(data
, m
, val
);
914 modes
+= strlen(modes
) + 1;
918 static int ssh_channelcmp(void *av
, void *bv
)
920 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
921 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
922 if (a
->localid
< b
->localid
)
924 if (a
->localid
> b
->localid
)
928 static int ssh_channelfind(void *av
, void *bv
)
930 unsigned *a
= (unsigned *) av
;
931 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
939 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
941 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
942 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
944 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
945 return i
< 0 ?
-1 : +1;
946 if (a
->dport
> b
->dport
)
948 if (a
->dport
< b
->dport
)
953 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
955 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
956 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
958 if (a
->sport
> b
->sport
)
960 if (a
->sport
< b
->sport
)
966 * Special form of strcmp which can cope with NULL inputs. NULL is
967 * defined to sort before even the empty string.
969 static int nullstrcmp(const char *a
, const char *b
)
971 if (a
== NULL
&& b
== NULL
)
980 static int ssh_portcmp(void *av
, void *bv
)
982 struct ssh_portfwd
*a
= (struct ssh_portfwd
*) av
;
983 struct ssh_portfwd
*b
= (struct ssh_portfwd
*) bv
;
985 if (a
->type
> b
->type
)
987 if (a
->type
< b
->type
)
989 if (a
->addressfamily
> b
->addressfamily
)
991 if (a
->addressfamily
< b
->addressfamily
)
993 if ( (i
= nullstrcmp(a
->saddr
, b
->saddr
)) != 0)
994 return i
< 0 ?
-1 : +1;
995 if (a
->sport
> b
->sport
)
997 if (a
->sport
< b
->sport
)
999 if (a
->type
!= 'D') {
1000 if ( (i
= nullstrcmp(a
->daddr
, b
->daddr
)) != 0)
1001 return i
< 0 ?
-1 : +1;
1002 if (a
->dport
> b
->dport
)
1004 if (a
->dport
< b
->dport
)
1010 static int alloc_channel_id(Ssh ssh
)
1012 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
1013 unsigned low
, high
, mid
;
1015 struct ssh_channel
*c
;
1018 * First-fit allocation of channel numbers: always pick the
1019 * lowest unused one. To do this, binary-search using the
1020 * counted B-tree to find the largest channel ID which is in a
1021 * contiguous sequence from the beginning. (Precisely
1022 * everything in that sequence must have ID equal to its tree
1023 * index plus CHANNEL_NUMBER_OFFSET.)
1025 tsize
= count234(ssh
->channels
);
1029 while (high
- low
> 1) {
1030 mid
= (high
+ low
) / 2;
1031 c
= index234(ssh
->channels
, mid
);
1032 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
1033 low
= mid
; /* this one is fine */
1035 high
= mid
; /* this one is past it */
1038 * Now low points to either -1, or the tree index of the
1039 * largest ID in the initial sequence.
1042 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
1043 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
1045 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
1048 static void c_write(Ssh ssh
, const char *buf
, int len
)
1050 if ((flags
& FLAG_STDERR
)) {
1052 for (i
= 0; i
< len
; i
++)
1054 fputc(buf
[i
], stderr
);
1057 from_backend(ssh
->frontend
, 1, buf
, len
);
1060 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
1063 for (i
= 0; i
< len
; i
++) {
1065 c_write(ssh
, "\r\n", 2);
1066 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
1067 c_write(ssh
, buf
+ i
, 1);
1071 static void c_write_str(Ssh ssh
, const char *buf
)
1073 c_write(ssh
, buf
, strlen(buf
));
1076 static void ssh_free_packet(struct Packet
*pkt
)
1081 static struct Packet
*ssh_new_packet(void)
1083 struct Packet
*pkt
= snew(struct Packet
);
1085 pkt
->body
= pkt
->data
= NULL
;
1087 pkt
->logmode
= PKTLOG_EMIT
;
1095 * Collect incoming data in the incoming packet buffer.
1096 * Decipher and verify the packet when it is completely read.
1097 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
1098 * Update the *data and *datalen variables.
1099 * Return a Packet structure when a packet is completed.
1101 static struct Packet
*ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1103 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
1105 crBegin(ssh
->ssh1_rdpkt_crstate
);
1107 st
->pktin
= ssh_new_packet();
1109 st
->pktin
->type
= 0;
1110 st
->pktin
->length
= 0;
1112 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
1113 while ((*datalen
) == 0)
1115 st
->len
= (st
->len
<< 8) + **data
;
1116 (*data
)++, (*datalen
)--;
1119 st
->pad
= 8 - (st
->len
% 8);
1120 st
->biglen
= st
->len
+ st
->pad
;
1121 st
->pktin
->length
= st
->len
- 5;
1123 if (st
->biglen
< 0) {
1124 bombout(("Extremely large packet length from server suggests"
1125 " data stream corruption"));
1126 ssh_free_packet(st
->pktin
);
1130 st
->pktin
->maxlen
= st
->biglen
;
1131 st
->pktin
->data
= snewn(st
->biglen
+ APIEXTRA
, unsigned char);
1133 st
->to_read
= st
->biglen
;
1134 st
->p
= st
->pktin
->data
;
1135 while (st
->to_read
> 0) {
1136 st
->chunk
= st
->to_read
;
1137 while ((*datalen
) == 0)
1139 if (st
->chunk
> (*datalen
))
1140 st
->chunk
= (*datalen
);
1141 memcpy(st
->p
, *data
, st
->chunk
);
1143 *datalen
-= st
->chunk
;
1145 st
->to_read
-= st
->chunk
;
1148 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, st
->pktin
->data
,
1149 st
->biglen
, NULL
)) {
1150 bombout(("Network attack (CRC compensation) detected!"));
1151 ssh_free_packet(st
->pktin
);
1156 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, st
->pktin
->data
, st
->biglen
);
1158 st
->realcrc
= crc32_compute(st
->pktin
->data
, st
->biglen
- 4);
1159 st
->gotcrc
= GET_32BIT(st
->pktin
->data
+ st
->biglen
- 4);
1160 if (st
->gotcrc
!= st
->realcrc
) {
1161 bombout(("Incorrect CRC received on packet"));
1162 ssh_free_packet(st
->pktin
);
1166 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1167 st
->pktin
->savedpos
= 0;
1169 if (ssh
->v1_compressing
) {
1170 unsigned char *decompblk
;
1172 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
1173 st
->pktin
->body
- 1, st
->pktin
->length
+ 1,
1174 &decompblk
, &decomplen
)) {
1175 bombout(("Zlib decompression encountered invalid data"));
1176 ssh_free_packet(st
->pktin
);
1180 if (st
->pktin
->maxlen
< st
->pad
+ decomplen
) {
1181 st
->pktin
->maxlen
= st
->pad
+ decomplen
;
1182 st
->pktin
->data
= sresize(st
->pktin
->data
,
1183 st
->pktin
->maxlen
+ APIEXTRA
,
1185 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1188 memcpy(st
->pktin
->body
- 1, decompblk
, decomplen
);
1190 st
->pktin
->length
= decomplen
- 1;
1193 st
->pktin
->type
= st
->pktin
->body
[-1];
1196 * Log incoming packet, possibly omitting sensitive fields.
1200 struct logblank_t blank
;
1201 if (ssh
->cfg
.logomitdata
) {
1202 int do_blank
= FALSE
, blank_prefix
= 0;
1203 /* "Session data" packets - omit the data field */
1204 if ((st
->pktin
->type
== SSH1_SMSG_STDOUT_DATA
) ||
1205 (st
->pktin
->type
== SSH1_SMSG_STDERR_DATA
)) {
1206 do_blank
= TRUE
; blank_prefix
= 0;
1207 } else if (st
->pktin
->type
== SSH1_MSG_CHANNEL_DATA
) {
1208 do_blank
= TRUE
; blank_prefix
= 4;
1211 blank
.offset
= blank_prefix
;
1212 blank
.len
= st
->pktin
->length
;
1213 blank
.type
= PKTLOG_OMIT
;
1217 log_packet(ssh
->logctx
,
1218 PKT_INCOMING
, st
->pktin
->type
,
1219 ssh1_pkt_type(st
->pktin
->type
),
1220 st
->pktin
->body
, st
->pktin
->length
,
1224 crFinish(st
->pktin
);
1227 static struct Packet
*ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1229 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1231 crBegin(ssh
->ssh2_rdpkt_crstate
);
1233 st
->pktin
= ssh_new_packet();
1235 st
->pktin
->type
= 0;
1236 st
->pktin
->length
= 0;
1238 st
->cipherblk
= ssh
->sccipher
->blksize
;
1241 if (st
->cipherblk
< 8)
1244 st
->pktin
->data
= snewn(st
->cipherblk
+ APIEXTRA
, unsigned char);
1247 * Acquire and decrypt the first block of the packet. This will
1248 * contain the length and padding details.
1250 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1251 while ((*datalen
) == 0)
1253 st
->pktin
->data
[st
->i
] = *(*data
)++;
1258 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1259 st
->pktin
->data
, st
->cipherblk
);
1262 * Now get the length and padding figures.
1264 st
->len
= GET_32BIT(st
->pktin
->data
);
1265 st
->pad
= st
->pktin
->data
[4];
1268 * _Completely_ silly lengths should be stomped on before they
1269 * do us any more damage.
1271 if (st
->len
< 0 || st
->len
> 35000 || st
->pad
< 4 ||
1272 st
->len
- st
->pad
< 1 || (st
->len
+ 4) % st
->cipherblk
!= 0) {
1273 bombout(("Incoming packet was garbled on decryption"));
1274 ssh_free_packet(st
->pktin
);
1279 * This enables us to deduce the payload length.
1281 st
->payload
= st
->len
- st
->pad
- 1;
1283 st
->pktin
->length
= st
->payload
+ 5;
1286 * So now we can work out the total packet length.
1288 st
->packetlen
= st
->len
+ 4;
1289 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1292 * Allocate memory for the rest of the packet.
1294 st
->pktin
->maxlen
= st
->packetlen
+ st
->maclen
;
1295 st
->pktin
->data
= sresize(st
->pktin
->data
,
1296 st
->pktin
->maxlen
+ APIEXTRA
,
1300 * Read and decrypt the remainder of the packet.
1302 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1304 while ((*datalen
) == 0)
1306 st
->pktin
->data
[st
->i
] = *(*data
)++;
1309 /* Decrypt everything _except_ the MAC. */
1311 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1312 st
->pktin
->data
+ st
->cipherblk
,
1313 st
->packetlen
- st
->cipherblk
);
1315 st
->pktin
->encrypted_len
= st
->packetlen
;
1321 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, st
->pktin
->data
, st
->len
+ 4,
1322 st
->incoming_sequence
)) {
1323 bombout(("Incorrect MAC received on packet"));
1324 ssh_free_packet(st
->pktin
);
1328 st
->pktin
->sequence
= st
->incoming_sequence
++;
1331 * Decompress packet payload.
1334 unsigned char *newpayload
;
1337 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1338 st
->pktin
->data
+ 5, st
->pktin
->length
- 5,
1339 &newpayload
, &newlen
)) {
1340 if (st
->pktin
->maxlen
< newlen
+ 5) {
1341 st
->pktin
->maxlen
= newlen
+ 5;
1342 st
->pktin
->data
= sresize(st
->pktin
->data
,
1343 st
->pktin
->maxlen
+ APIEXTRA
,
1346 st
->pktin
->length
= 5 + newlen
;
1347 memcpy(st
->pktin
->data
+ 5, newpayload
, newlen
);
1352 st
->pktin
->savedpos
= 6;
1353 st
->pktin
->body
= st
->pktin
->data
;
1354 st
->pktin
->type
= st
->pktin
->data
[5];
1357 * Log incoming packet, possibly omitting sensitive fields.
1361 struct logblank_t blank
;
1362 if (ssh
->cfg
.logomitdata
) {
1363 int do_blank
= FALSE
, blank_prefix
= 0;
1364 /* "Session data" packets - omit the data field */
1365 if (st
->pktin
->type
== SSH2_MSG_CHANNEL_DATA
) {
1366 do_blank
= TRUE
; blank_prefix
= 4;
1367 } else if (st
->pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1368 do_blank
= TRUE
; blank_prefix
= 8;
1371 blank
.offset
= blank_prefix
;
1372 blank
.len
= (st
->pktin
->length
-6) - blank_prefix
;
1373 blank
.type
= PKTLOG_OMIT
;
1377 log_packet(ssh
->logctx
, PKT_INCOMING
, st
->pktin
->type
,
1378 ssh2_pkt_type(ssh
->pkt_ctx
, st
->pktin
->type
),
1379 st
->pktin
->data
+6, st
->pktin
->length
-6,
1383 crFinish(st
->pktin
);
1386 static int s_wrpkt_prepare(Ssh ssh
, struct Packet
*pkt
, int *offset_p
)
1388 int pad
, biglen
, i
, pktoffs
;
1392 * XXX various versions of SC (including 8.8.4) screw up the
1393 * register allocation in this function and use the same register
1394 * (D6) for len and as a temporary, with predictable results. The
1395 * following sledgehammer prevents this.
1402 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[12],
1403 ssh1_pkt_type(pkt
->data
[12]),
1404 pkt
->body
, pkt
->length
- (pkt
->body
- pkt
->data
),
1405 pkt
->nblanks
, pkt
->blanks
);
1406 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1409 if (ssh
->v1_compressing
) {
1410 unsigned char *compblk
;
1412 zlib_compress_block(ssh
->cs_comp_ctx
,
1413 pkt
->data
+ 12, pkt
->length
- 12,
1414 &compblk
, &complen
);
1415 memcpy(pkt
->data
+ 12, compblk
, complen
);
1417 pkt
->length
= complen
+ 12;
1420 ssh_pkt_ensure(pkt
, pkt
->length
+ 4); /* space for CRC */
1422 len
= pkt
->length
- 4 - 8; /* len(type+data+CRC) */
1423 pad
= 8 - (len
% 8);
1425 biglen
= len
+ pad
; /* len(padding+type+data+CRC) */
1427 for (i
= pktoffs
; i
< 4+8; i
++)
1428 pkt
->data
[i
] = random_byte();
1429 crc
= crc32_compute(pkt
->data
+ pktoffs
+ 4, biglen
- 4); /* all ex len */
1430 PUT_32BIT(pkt
->data
+ pktoffs
+ 4 + biglen
- 4, crc
);
1431 PUT_32BIT(pkt
->data
+ pktoffs
, len
);
1434 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
,
1435 pkt
->data
+ pktoffs
+ 4, biglen
);
1437 if (offset_p
) *offset_p
= pktoffs
;
1438 return biglen
+ 4; /* len(length+padding+type+data+CRC) */
1441 static void s_wrpkt(Ssh ssh
, struct Packet
*pkt
)
1443 int len
, backlog
, offset
;
1444 len
= s_wrpkt_prepare(ssh
, pkt
, &offset
);
1445 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
+ offset
, len
);
1446 if (backlog
> SSH_MAX_BACKLOG
)
1447 ssh_throttle_all(ssh
, 1, backlog
);
1448 ssh_free_packet(pkt
);
1451 static void s_wrpkt_defer(Ssh ssh
, struct Packet
*pkt
)
1454 len
= s_wrpkt_prepare(ssh
, pkt
, &offset
);
1455 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1456 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1457 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1461 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
,
1462 pkt
->data
+ offset
, len
);
1463 ssh
->deferred_len
+= len
;
1464 ssh_free_packet(pkt
);
1468 * Construct a SSH-1 packet with the specified contents.
1469 * (This all-at-once interface used to be the only one, but now SSH-1
1470 * packets can also be constructed incrementally.)
1472 static struct Packet
*construct_packet(Ssh ssh
, int pkttype
, va_list ap
)
1478 pkt
= ssh1_pkt_init(pkttype
);
1480 while ((argtype
= va_arg(ap
, int)) != PKT_END
) {
1481 unsigned char *argp
, argchar
;
1482 unsigned long argint
;
1485 /* Actual fields in the packet */
1487 argint
= va_arg(ap
, int);
1488 ssh_pkt_adduint32(pkt
, argint
);
1491 argchar
= (unsigned char) va_arg(ap
, int);
1492 ssh_pkt_addbyte(pkt
, argchar
);
1495 argp
= va_arg(ap
, unsigned char *);
1496 arglen
= va_arg(ap
, int);
1497 ssh_pkt_adddata(pkt
, argp
, arglen
);
1500 argp
= va_arg(ap
, unsigned char *);
1501 ssh_pkt_addstring(pkt
, argp
);
1504 bn
= va_arg(ap
, Bignum
);
1505 ssh1_pkt_addmp(pkt
, bn
);
1507 /* Tokens for modifications to packet logging */
1509 dont_log_password(ssh
, pkt
, PKTLOG_BLANK
);
1512 dont_log_data(ssh
, pkt
, PKTLOG_OMIT
);
1515 end_log_omission(ssh
, pkt
);
1523 static void send_packet(Ssh ssh
, int pkttype
, ...)
1527 va_start(ap
, pkttype
);
1528 pkt
= construct_packet(ssh
, pkttype
, ap
);
1533 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1537 va_start(ap
, pkttype
);
1538 pkt
= construct_packet(ssh
, pkttype
, ap
);
1540 s_wrpkt_defer(ssh
, pkt
);
1543 static int ssh_versioncmp(char *a
, char *b
)
1546 unsigned long av
, bv
;
1548 av
= strtoul(a
, &ae
, 10);
1549 bv
= strtoul(b
, &be
, 10);
1551 return (av
< bv ?
-1 : +1);
1556 av
= strtoul(ae
, &ae
, 10);
1557 bv
= strtoul(be
, &be
, 10);
1559 return (av
< bv ?
-1 : +1);
1564 * Utility routines for putting an SSH-protocol `string' and
1565 * `uint32' into a SHA state.
1567 static void sha_string(SHA_State
* s
, void *str
, int len
)
1569 unsigned char lenblk
[4];
1570 PUT_32BIT(lenblk
, len
);
1571 SHA_Bytes(s
, lenblk
, 4);
1572 SHA_Bytes(s
, str
, len
);
1575 static void sha_uint32(SHA_State
* s
, unsigned i
)
1577 unsigned char intblk
[4];
1578 PUT_32BIT(intblk
, i
);
1579 SHA_Bytes(s
, intblk
, 4);
1583 * Packet construction functions. Mostly shared between SSH-1 and SSH-2.
1585 static void ssh_pkt_ensure(struct Packet
*pkt
, int length
)
1587 if (pkt
->maxlen
< length
) {
1588 unsigned char *body
= pkt
->body
;
1589 int offset
= body ? pkt
->data
- body
: 0;
1590 pkt
->maxlen
= length
+ 256;
1591 pkt
->data
= sresize(pkt
->data
, pkt
->maxlen
+ APIEXTRA
, unsigned char);
1592 if (body
) pkt
->body
= pkt
->data
+ offset
;
1595 static void ssh_pkt_adddata(struct Packet
*pkt
, void *data
, int len
)
1597 if (pkt
->logmode
!= PKTLOG_EMIT
) {
1599 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
, struct logblank_t
);
1601 pkt
->blanks
[pkt
->nblanks
-1].offset
= pkt
->length
-
1602 (pkt
->body
- pkt
->data
);
1603 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1604 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1607 ssh_pkt_ensure(pkt
, pkt
->length
);
1608 memcpy(pkt
->data
+ pkt
->length
- len
, data
, len
);
1610 static void ssh_pkt_addbyte(struct Packet
*pkt
, unsigned char byte
)
1612 ssh_pkt_adddata(pkt
, &byte
, 1);
1614 static void ssh2_pkt_addbool(struct Packet
*pkt
, unsigned char value
)
1616 ssh_pkt_adddata(pkt
, &value
, 1);
1618 static void ssh_pkt_adduint32(struct Packet
*pkt
, unsigned long value
)
1621 PUT_32BIT(x
, value
);
1622 ssh_pkt_adddata(pkt
, x
, 4);
1624 static void ssh_pkt_addstring_start(struct Packet
*pkt
)
1626 ssh_pkt_adduint32(pkt
, 0);
1627 pkt
->savedpos
= pkt
->length
;
1629 static void ssh_pkt_addstring_str(struct Packet
*pkt
, char *data
)
1631 ssh_pkt_adddata(pkt
, data
, strlen(data
));
1632 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1634 static void ssh_pkt_addstring_data(struct Packet
*pkt
, char *data
, int len
)
1636 ssh_pkt_adddata(pkt
, data
, len
);
1637 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1639 static void ssh_pkt_addstring(struct Packet
*pkt
, char *data
)
1641 ssh_pkt_addstring_start(pkt
);
1642 ssh_pkt_addstring_str(pkt
, data
);
1644 static void ssh1_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1646 int len
= ssh1_bignum_length(b
);
1647 unsigned char *data
= snewn(len
, char);
1648 (void) ssh1_write_bignum(data
, b
);
1649 ssh_pkt_adddata(pkt
, data
, len
);
1652 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1655 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1656 p
= snewn(n
+ 1, unsigned char);
1658 for (i
= 1; i
<= n
; i
++)
1659 p
[i
] = bignum_byte(b
, n
- i
);
1661 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1663 memmove(p
, p
+ i
, n
+ 1 - i
);
1667 static void ssh2_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1671 p
= ssh2_mpint_fmt(b
, &len
);
1672 ssh_pkt_addstring_start(pkt
);
1673 ssh_pkt_addstring_data(pkt
, (char *)p
, len
);
1677 static struct Packet
*ssh1_pkt_init(int pkt_type
)
1679 struct Packet
*pkt
= ssh_new_packet();
1680 pkt
->length
= 4 + 8; /* space for length + max padding */
1681 ssh_pkt_addbyte(pkt
, pkt_type
);
1682 pkt
->body
= pkt
->data
+ pkt
->length
;
1686 /* For legacy code (SSH-1 and -2 packet construction used to be separate) */
1687 #define ssh2_pkt_ensure(pkt, length) ssh_pkt_ensure(pkt, length)
1688 #define ssh2_pkt_adddata(pkt, data, len) ssh_pkt_adddata(pkt, data, len)
1689 #define ssh2_pkt_addbyte(pkt, byte) ssh_pkt_addbyte(pkt, byte)
1690 #define ssh2_pkt_adduint32(pkt, value) ssh_pkt_adduint32(pkt, value)
1691 #define ssh2_pkt_addstring_start(pkt) ssh_pkt_addstring_start(pkt)
1692 #define ssh2_pkt_addstring_str(pkt, data) ssh_pkt_addstring_str(pkt, data)
1693 #define ssh2_pkt_addstring_data(pkt, data, len) ssh_pkt_addstring_data(pkt, data, len)
1694 #define ssh2_pkt_addstring(pkt, data) ssh_pkt_addstring(pkt, data)
1696 static struct Packet
*ssh2_pkt_init(int pkt_type
)
1698 struct Packet
*pkt
= ssh_new_packet();
1701 ssh_pkt_addbyte(pkt
, (unsigned char) pkt_type
);
1702 pkt
->body
= pkt
->data
+ pkt
->length
;
1707 * Construct an SSH-2 final-form packet: compress it, encrypt it,
1708 * put the MAC on it. Final packet, ready to be sent, is stored in
1709 * pkt->data. Total length is returned.
1711 static int ssh2_pkt_construct(Ssh ssh
, struct Packet
*pkt
)
1713 int cipherblk
, maclen
, padding
, i
;
1716 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[5],
1717 ssh2_pkt_type(ssh
->pkt_ctx
, pkt
->data
[5]),
1718 pkt
->body
, pkt
->length
- (pkt
->body
- pkt
->data
),
1719 pkt
->nblanks
, pkt
->blanks
);
1720 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1724 * Compress packet payload.
1727 unsigned char *newpayload
;
1730 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, pkt
->data
+ 5,
1732 &newpayload
, &newlen
)) {
1734 ssh2_pkt_adddata(pkt
, newpayload
, newlen
);
1740 * Add padding. At least four bytes, and must also bring total
1741 * length (minus MAC) up to a multiple of the block size.
1742 * If pkt->forcepad is set, make sure the packet is at least that size
1745 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1746 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1748 if (pkt
->length
+ padding
< pkt
->forcepad
)
1749 padding
= pkt
->forcepad
- pkt
->length
;
1751 (cipherblk
- (pkt
->length
+ padding
) % cipherblk
) % cipherblk
;
1752 assert(padding
<= 255);
1753 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1754 ssh2_pkt_ensure(pkt
, pkt
->length
+ padding
+ maclen
);
1755 pkt
->data
[4] = padding
;
1756 for (i
= 0; i
< padding
; i
++)
1757 pkt
->data
[pkt
->length
+ i
] = random_byte();
1758 PUT_32BIT(pkt
->data
, pkt
->length
+ padding
- 4);
1760 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, pkt
->data
,
1761 pkt
->length
+ padding
,
1762 ssh
->v2_outgoing_sequence
);
1763 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1766 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1767 pkt
->data
, pkt
->length
+ padding
);
1769 pkt
->encrypted_len
= pkt
->length
+ padding
;
1771 /* Ready-to-send packet starts at pkt->data. We return length. */
1772 return pkt
->length
+ padding
+ maclen
;
1776 * Routines called from the main SSH code to send packets. There
1777 * are quite a few of these, because we have two separate
1778 * mechanisms for delaying the sending of packets:
1780 * - In order to send an IGNORE message and a password message in
1781 * a single fixed-length blob, we require the ability to
1782 * concatenate the encrypted forms of those two packets _into_ a
1783 * single blob and then pass it to our <network.h> transport
1784 * layer in one go. Hence, there's a deferment mechanism which
1785 * works after packet encryption.
1787 * - In order to avoid sending any connection-layer messages
1788 * during repeat key exchange, we have to queue up any such
1789 * outgoing messages _before_ they are encrypted (and in
1790 * particular before they're allocated sequence numbers), and
1791 * then send them once we've finished.
1793 * I call these mechanisms `defer' and `queue' respectively, so as
1794 * to distinguish them reasonably easily.
1796 * The functions send_noqueue() and defer_noqueue() free the packet
1797 * structure they are passed. Every outgoing packet goes through
1798 * precisely one of these functions in its life; packets passed to
1799 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1800 * these or get queued, and then when the queue is later emptied
1801 * the packets are all passed to defer_noqueue().
1803 * When using a CBC-mode cipher, it's necessary to ensure that an
1804 * attacker can't provide data to be encrypted using an IV that they
1805 * know. We ensure this by prefixing each packet that might contain
1806 * user data with an SSH_MSG_IGNORE. This is done using the deferral
1807 * mechanism, so in this case send_noqueue() ends up redirecting to
1808 * defer_noqueue(). If you don't like this inefficiency, don't use
1812 static void ssh2_pkt_defer_noqueue(Ssh
, struct Packet
*, int);
1813 static void ssh_pkt_defersend(Ssh
);
1816 * Send an SSH-2 packet immediately, without queuing or deferring.
1818 static void ssh2_pkt_send_noqueue(Ssh ssh
, struct Packet
*pkt
)
1822 if (ssh
->cscipher
!= NULL
&& (ssh
->cscipher
->flags
& SSH_CIPHER_IS_CBC
)) {
1823 /* We need to send two packets, so use the deferral mechanism. */
1824 ssh2_pkt_defer_noqueue(ssh
, pkt
, FALSE
);
1825 ssh_pkt_defersend(ssh
);
1828 len
= ssh2_pkt_construct(ssh
, pkt
);
1829 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1830 if (backlog
> SSH_MAX_BACKLOG
)
1831 ssh_throttle_all(ssh
, 1, backlog
);
1833 ssh
->outgoing_data_size
+= pkt
->encrypted_len
;
1834 if (!ssh
->kex_in_progress
&&
1835 ssh
->max_data_size
!= 0 &&
1836 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1837 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1839 ssh_free_packet(pkt
);
1843 * Defer an SSH-2 packet.
1845 static void ssh2_pkt_defer_noqueue(Ssh ssh
, struct Packet
*pkt
, int noignore
)
1848 if (ssh
->cscipher
!= NULL
&& (ssh
->cscipher
->flags
& SSH_CIPHER_IS_CBC
) &&
1849 ssh
->deferred_len
== 0 && !noignore
) {
1851 * Interpose an SSH_MSG_IGNORE to ensure that user data don't
1852 * get encrypted with a known IV.
1854 struct Packet
*ipkt
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
1855 ssh2_pkt_defer_noqueue(ssh
, ipkt
, TRUE
);
1857 len
= ssh2_pkt_construct(ssh
, pkt
);
1858 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1859 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1860 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1864 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1865 ssh
->deferred_len
+= len
;
1866 ssh
->deferred_data_size
+= pkt
->encrypted_len
;
1867 ssh_free_packet(pkt
);
1871 * Queue an SSH-2 packet.
1873 static void ssh2_pkt_queue(Ssh ssh
, struct Packet
*pkt
)
1875 assert(ssh
->queueing
);
1877 if (ssh
->queuelen
>= ssh
->queuesize
) {
1878 ssh
->queuesize
= ssh
->queuelen
+ 32;
1879 ssh
->queue
= sresize(ssh
->queue
, ssh
->queuesize
, struct Packet
*);
1882 ssh
->queue
[ssh
->queuelen
++] = pkt
;
1886 * Either queue or send a packet, depending on whether queueing is
1889 static void ssh2_pkt_send(Ssh ssh
, struct Packet
*pkt
)
1892 ssh2_pkt_queue(ssh
, pkt
);
1894 ssh2_pkt_send_noqueue(ssh
, pkt
);
1899 * Either queue or defer a packet, depending on whether queueing is
1902 static void ssh2_pkt_defer(Ssh ssh
, struct Packet
*pkt
)
1905 ssh2_pkt_queue(ssh
, pkt
);
1907 ssh2_pkt_defer_noqueue(ssh
, pkt
, FALSE
);
1912 * Send the whole deferred data block constructed by
1913 * ssh2_pkt_defer() or SSH-1's defer_packet().
1915 * The expected use of the defer mechanism is that you call
1916 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1917 * not currently queueing, this simply sets up deferred_send_data
1918 * and then sends it. If we _are_ currently queueing, the calls to
1919 * ssh2_pkt_defer() put the deferred packets on to the queue
1920 * instead, and therefore ssh_pkt_defersend() has no deferred data
1921 * to send. Hence, there's no need to make it conditional on
1924 static void ssh_pkt_defersend(Ssh ssh
)
1927 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1929 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1930 sfree(ssh
->deferred_send_data
);
1931 ssh
->deferred_send_data
= NULL
;
1932 if (backlog
> SSH_MAX_BACKLOG
)
1933 ssh_throttle_all(ssh
, 1, backlog
);
1935 ssh
->outgoing_data_size
+= ssh
->deferred_data_size
;
1936 if (!ssh
->kex_in_progress
&&
1937 ssh
->max_data_size
!= 0 &&
1938 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1939 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1940 ssh
->deferred_data_size
= 0;
1944 * Send all queued SSH-2 packets. We send them by means of
1945 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1946 * packets that needed to be lumped together.
1948 static void ssh2_pkt_queuesend(Ssh ssh
)
1952 assert(!ssh
->queueing
);
1954 for (i
= 0; i
< ssh
->queuelen
; i
++)
1955 ssh2_pkt_defer_noqueue(ssh
, ssh
->queue
[i
], FALSE
);
1958 ssh_pkt_defersend(ssh
);
1962 void bndebug(char *string
, Bignum b
)
1966 p
= ssh2_mpint_fmt(b
, &len
);
1967 debug(("%s", string
));
1968 for (i
= 0; i
< len
; i
++)
1969 debug((" %02x", p
[i
]));
1975 static void sha_mpint(SHA_State
* s
, Bignum b
)
1979 p
= ssh2_mpint_fmt(b
, &len
);
1980 sha_string(s
, p
, len
);
1985 * Packet decode functions for both SSH-1 and SSH-2.
1987 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
)
1989 unsigned long value
;
1990 if (pkt
->length
- pkt
->savedpos
< 4)
1991 return 0; /* arrgh, no way to decline (FIXME?) */
1992 value
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1996 static int ssh2_pkt_getbool(struct Packet
*pkt
)
1998 unsigned long value
;
1999 if (pkt
->length
- pkt
->savedpos
< 1)
2000 return 0; /* arrgh, no way to decline (FIXME?) */
2001 value
= pkt
->body
[pkt
->savedpos
] != 0;
2005 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
)
2010 if (pkt
->length
- pkt
->savedpos
< 4)
2012 len
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
2017 if (pkt
->length
- pkt
->savedpos
< *length
)
2019 *p
= (char *)(pkt
->body
+ pkt
->savedpos
);
2020 pkt
->savedpos
+= *length
;
2022 static void *ssh_pkt_getdata(struct Packet
*pkt
, int length
)
2024 if (pkt
->length
- pkt
->savedpos
< length
)
2026 pkt
->savedpos
+= length
;
2027 return pkt
->body
+ (pkt
->savedpos
- length
);
2029 static int ssh1_pkt_getrsakey(struct Packet
*pkt
, struct RSAKey
*key
,
2030 unsigned char **keystr
)
2034 j
= makekey(pkt
->body
+ pkt
->savedpos
,
2035 pkt
->length
- pkt
->savedpos
,
2042 assert(pkt
->savedpos
< pkt
->length
);
2046 static Bignum
ssh1_pkt_getmp(struct Packet
*pkt
)
2051 j
= ssh1_read_bignum(pkt
->body
+ pkt
->savedpos
,
2052 pkt
->length
- pkt
->savedpos
, &b
);
2060 static Bignum
ssh2_pkt_getmp(struct Packet
*pkt
)
2066 ssh_pkt_getstring(pkt
, &p
, &length
);
2071 b
= bignum_from_bytes((unsigned char *)p
, length
);
2076 * Helper function to add an SSH-2 signature blob to a packet.
2077 * Expects to be shown the public key blob as well as the signature
2078 * blob. Normally works just like ssh2_pkt_addstring, but will
2079 * fiddle with the signature packet if necessary for
2080 * BUG_SSH2_RSA_PADDING.
2082 static void ssh2_add_sigblob(Ssh ssh
, struct Packet
*pkt
,
2083 void *pkblob_v
, int pkblob_len
,
2084 void *sigblob_v
, int sigblob_len
)
2086 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
2087 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
2089 /* dmemdump(pkblob, pkblob_len); */
2090 /* dmemdump(sigblob, sigblob_len); */
2093 * See if this is in fact an ssh-rsa signature and a buggy
2094 * server; otherwise we can just do this the easy way.
2096 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
2097 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
2098 int pos
, len
, siglen
;
2101 * Find the byte length of the modulus.
2104 pos
= 4+7; /* skip over "ssh-rsa" */
2105 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
2106 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
2107 pos
+= 4; /* find modulus itself */
2108 while (len
> 0 && pkblob
[pos
] == 0)
2110 /* debug(("modulus length is %d\n", len)); */
2113 * Now find the signature integer.
2115 pos
= 4+7; /* skip over "ssh-rsa" */
2116 siglen
= GET_32BIT(sigblob
+pos
);
2117 /* debug(("signature length is %d\n", siglen)); */
2119 if (len
!= siglen
) {
2120 unsigned char newlen
[4];
2121 ssh2_pkt_addstring_start(pkt
);
2122 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, pos
);
2123 /* dmemdump(sigblob, pos); */
2124 pos
+= 4; /* point to start of actual sig */
2125 PUT_32BIT(newlen
, len
);
2126 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 4);
2127 /* dmemdump(newlen, 4); */
2129 while (len
-- > siglen
) {
2130 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 1);
2131 /* dmemdump(newlen, 1); */
2133 ssh2_pkt_addstring_data(pkt
, (char *)(sigblob
+pos
), siglen
);
2134 /* dmemdump(sigblob+pos, siglen); */
2138 /* Otherwise fall through and do it the easy way. */
2141 ssh2_pkt_addstring_start(pkt
);
2142 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, sigblob_len
);
2146 * Examine the remote side's version string and compare it against
2147 * a list of known buggy implementations.
2149 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
2151 char *imp
; /* pointer to implementation part */
2153 imp
+= strcspn(imp
, "-");
2155 imp
+= strcspn(imp
, "-");
2158 ssh
->remote_bugs
= 0;
2160 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
2161 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
2162 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
2163 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
2164 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
2165 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
2167 * These versions don't support SSH1_MSG_IGNORE, so we have
2168 * to use a different defence against password length
2171 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
2172 logevent("We believe remote version has SSH-1 ignore bug");
2175 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
2176 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
2177 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
2179 * These versions need a plain password sent; they can't
2180 * handle having a null and a random length of data after
2183 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
2184 logevent("We believe remote version needs a plain SSH-1 password");
2187 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
2188 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
2189 (!strcmp(imp
, "Cisco-1.25")))) {
2191 * These versions apparently have no clue whatever about
2192 * RSA authentication and will panic and die if they see
2193 * an AUTH_RSA message.
2195 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
2196 logevent("We believe remote version can't handle SSH-1 RSA authentication");
2199 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
2200 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
2201 !wc_match("* VShell", imp
) &&
2202 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
2203 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
2204 wc_match("2.1 *", imp
)))) {
2206 * These versions have the HMAC bug.
2208 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
2209 logevent("We believe remote version has SSH-2 HMAC bug");
2212 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2213 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2214 !wc_match("* VShell", imp
) &&
2215 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2217 * These versions have the key-derivation bug (failing to
2218 * include the literal shared secret in the hashes that
2219 * generate the keys).
2221 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2222 logevent("We believe remote version has SSH-2 key-derivation bug");
2225 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2226 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2227 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2228 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2230 * These versions have the SSH-2 RSA padding bug.
2232 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2233 logevent("We believe remote version has SSH-2 RSA padding bug");
2236 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2237 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2238 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2240 * These versions have the SSH-2 session-ID bug in
2241 * public-key authentication.
2243 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2244 logevent("We believe remote version has SSH-2 public-key-session-ID bug");
2247 if (ssh
->cfg
.sshbug_rekey2
== FORCE_ON
||
2248 (ssh
->cfg
.sshbug_rekey2
== AUTO
&&
2249 (wc_match("DigiSSH_2.0", imp
) ||
2250 wc_match("OpenSSH_2.[0-4]*", imp
) ||
2251 wc_match("OpenSSH_2.5.[0-3]*", imp
) ||
2252 wc_match("Sun_SSH_1.0", imp
) ||
2253 wc_match("Sun_SSH_1.0.1", imp
) ||
2254 /* All versions <= 1.2.6 (they changed their format in 1.2.7) */
2255 wc_match("WeOnlyDo-*", imp
)))) {
2257 * These versions have the SSH-2 rekey bug.
2259 ssh
->remote_bugs
|= BUG_SSH2_REKEY
;
2260 logevent("We believe remote version has SSH-2 rekey bug");
2265 * The `software version' part of an SSH version string is required
2266 * to contain no spaces or minus signs.
2268 static void ssh_fix_verstring(char *str
)
2270 /* Eat "SSH-<protoversion>-". */
2271 assert(*str
== 'S'); str
++;
2272 assert(*str
== 'S'); str
++;
2273 assert(*str
== 'H'); str
++;
2274 assert(*str
== '-'); str
++;
2275 while (*str
&& *str
!= '-') str
++;
2276 assert(*str
== '-'); str
++;
2278 /* Convert minus signs and spaces in the remaining string into
2281 if (*str
== '-' || *str
== ' ')
2287 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2289 struct do_ssh_init_state
{
2297 crState(do_ssh_init_state
);
2299 crBegin(ssh
->do_ssh_init_crstate
);
2301 /* Search for a line beginning with the string "SSH-" in the input. */
2303 if (c
!= 'S') goto no
;
2305 if (c
!= 'S') goto no
;
2307 if (c
!= 'H') goto no
;
2309 if (c
!= '-') goto no
;
2318 s
->vstring
= snewn(s
->vstrsize
, char);
2319 strcpy(s
->vstring
, "SSH-");
2323 crReturn(1); /* get another char */
2324 if (s
->vslen
>= s
->vstrsize
- 1) {
2326 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2328 s
->vstring
[s
->vslen
++] = c
;
2331 s
->version
[s
->i
] = '\0';
2333 } else if (s
->i
< sizeof(s
->version
) - 1)
2334 s
->version
[s
->i
++] = c
;
2335 } else if (c
== '\012')
2339 ssh
->agentfwd_enabled
= FALSE
;
2340 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2342 s
->vstring
[s
->vslen
] = 0;
2343 s
->vstring
[strcspn(s
->vstring
, "\015\012")] = '\0';/* remove EOL chars */
2344 logeventf(ssh
, "Server version: %s", s
->vstring
);
2345 ssh_detect_bugs(ssh
, s
->vstring
);
2348 * Decide which SSH protocol version to support.
2351 /* Anything strictly below "2.0" means protocol 1 is supported. */
2352 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2353 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2354 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2356 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2357 bombout(("SSH protocol version 1 required by user but not provided by server"));
2360 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2361 bombout(("SSH protocol version 2 required by user but not provided by server"));
2368 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2370 * Construct a v2 version string.
2372 verstring
= dupprintf("SSH-2.0-%s\015\012", sshver
);
2376 * Construct a v1 version string.
2378 verstring
= dupprintf("SSH-%s-%s\012",
2379 (ssh_versioncmp(s
->version
, "1.5") <= 0 ?
2380 s
->version
: "1.5"),
2385 ssh_fix_verstring(verstring
);
2387 if (ssh
->version
== 2) {
2390 * Hash our version string and their version string.
2392 len
= strcspn(verstring
, "\015\012");
2393 ssh
->v_c
= snewn(len
+ 1, char);
2394 memcpy(ssh
->v_c
, verstring
, len
);
2396 len
= strcspn(s
->vstring
, "\015\012");
2397 ssh
->v_s
= snewn(len
+ 1, char);
2398 memcpy(ssh
->v_s
, s
->vstring
, len
);
2402 * Initialise SSH-2 protocol.
2404 ssh
->protocol
= ssh2_protocol
;
2405 ssh2_protocol_setup(ssh
);
2406 ssh
->s_rdpkt
= ssh2_rdpkt
;
2409 * Initialise SSH-1 protocol.
2411 ssh
->protocol
= ssh1_protocol
;
2412 ssh1_protocol_setup(ssh
);
2413 ssh
->s_rdpkt
= ssh1_rdpkt
;
2415 logeventf(ssh
, "We claim version: %.*s",
2416 strcspn(verstring
, "\015\012"), verstring
);
2417 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2419 if (ssh
->version
== 2)
2420 do_ssh2_transport(ssh
, NULL
, -1, NULL
);
2423 logeventf(ssh
, "Using SSH protocol version %d", ssh
->version
);
2425 update_specials_menu(ssh
->frontend
);
2426 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2427 ssh
->pinger
= pinger_new(&ssh
->cfg
, &ssh_backend
, ssh
);
2434 static void ssh_process_incoming_data(Ssh ssh
,
2435 unsigned char **data
, int *datalen
)
2437 struct Packet
*pktin
= ssh
->s_rdpkt(ssh
, data
, datalen
);
2439 ssh
->protocol(ssh
, NULL
, 0, pktin
);
2440 ssh_free_packet(pktin
);
2444 static void ssh_queue_incoming_data(Ssh ssh
,
2445 unsigned char **data
, int *datalen
)
2447 bufchain_add(&ssh
->queued_incoming_data
, *data
, *datalen
);
2452 static void ssh_process_queued_incoming_data(Ssh ssh
)
2455 unsigned char *data
;
2458 while (!ssh
->frozen
&& bufchain_size(&ssh
->queued_incoming_data
)) {
2459 bufchain_prefix(&ssh
->queued_incoming_data
, &vdata
, &len
);
2463 while (!ssh
->frozen
&& len
> 0)
2464 ssh_process_incoming_data(ssh
, &data
, &len
);
2467 bufchain_consume(&ssh
->queued_incoming_data
, origlen
- len
);
2471 static void ssh_set_frozen(Ssh ssh
, int frozen
)
2474 sk_set_frozen(ssh
->s
, frozen
);
2475 ssh
->frozen
= frozen
;
2478 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2480 crBegin(ssh
->ssh_gotdata_crstate
);
2483 * To begin with, feed the characters one by one to the
2484 * protocol initialisation / selection function do_ssh_init().
2485 * When that returns 0, we're done with the initial greeting
2486 * exchange and can move on to packet discipline.
2489 int ret
; /* need not be kept across crReturn */
2491 crReturnV
; /* more data please */
2492 ret
= do_ssh_init(ssh
, *data
);
2500 * We emerge from that loop when the initial negotiation is
2501 * over and we have selected an s_rdpkt function. Now pass
2502 * everything to s_rdpkt, and then pass the resulting packets
2503 * to the proper protocol handler.
2507 while (bufchain_size(&ssh
->queued_incoming_data
) > 0 || datalen
> 0) {
2509 ssh_queue_incoming_data(ssh
, &data
, &datalen
);
2510 /* This uses up all data and cannot cause anything interesting
2511 * to happen; indeed, for anything to happen at all, we must
2512 * return, so break out. */
2514 } else if (bufchain_size(&ssh
->queued_incoming_data
) > 0) {
2515 /* This uses up some or all data, and may freeze the
2517 ssh_process_queued_incoming_data(ssh
);
2519 /* This uses up some or all data, and may freeze the
2521 ssh_process_incoming_data(ssh
, &data
, &datalen
);
2523 /* FIXME this is probably EBW. */
2524 if (ssh
->state
== SSH_STATE_CLOSED
)
2527 /* We're out of data. Go and get some more. */
2533 static int ssh_do_close(Ssh ssh
, int notify_exit
)
2536 struct ssh_channel
*c
;
2538 ssh
->state
= SSH_STATE_CLOSED
;
2539 expire_timer_context(ssh
);
2544 notify_remote_exit(ssh
->frontend
);
2549 * Now we must shut down any port- and X-forwarded channels going
2550 * through this connection.
2552 if (ssh
->channels
) {
2553 while (NULL
!= (c
= index234(ssh
->channels
, 0))) {
2556 x11_close(c
->u
.x11
.s
);
2559 pfd_close(c
->u
.pfd
.s
);
2562 del234(ssh
->channels
, c
); /* moving next one to index 0 */
2563 if (ssh
->version
== 2)
2564 bufchain_clear(&c
->v
.v2
.outbuffer
);
2569 * Go through port-forwardings, and close any associated
2570 * listening sockets.
2572 if (ssh
->portfwds
) {
2573 struct ssh_portfwd
*pf
;
2574 while (NULL
!= (pf
= index234(ssh
->portfwds
, 0))) {
2575 /* Dispose of any listening socket. */
2577 pfd_terminate(pf
->local
);
2578 del234(ssh
->portfwds
, pf
); /* moving next one to index 0 */
2586 static void ssh_log(Plug plug
, int type
, SockAddr addr
, int port
,
2587 const char *error_msg
, int error_code
)
2589 Ssh ssh
= (Ssh
) plug
;
2590 char addrbuf
[256], *msg
;
2592 sk_getaddr(addr
, addrbuf
, lenof(addrbuf
));
2595 msg
= dupprintf("Connecting to %s port %d", addrbuf
, port
);
2597 msg
= dupprintf("Failed to connect to %s: %s", addrbuf
, error_msg
);
2603 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2606 Ssh ssh
= (Ssh
) plug
;
2607 int need_notify
= ssh_do_close(ssh
, FALSE
);
2610 if (!ssh
->close_expected
)
2611 error_msg
= "Server unexpectedly closed network connection";
2613 error_msg
= "Server closed network connection";
2617 notify_remote_exit(ssh
->frontend
);
2620 logevent(error_msg
);
2621 if (!ssh
->close_expected
|| !ssh
->clean_exit
)
2622 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2626 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2628 Ssh ssh
= (Ssh
) plug
;
2629 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2630 if (ssh
->state
== SSH_STATE_CLOSED
) {
2631 ssh_do_close(ssh
, TRUE
);
2637 static void ssh_sent(Plug plug
, int bufsize
)
2639 Ssh ssh
= (Ssh
) plug
;
2641 * If the send backlog on the SSH socket itself clears, we
2642 * should unthrottle the whole world if it was throttled.
2644 if (bufsize
< SSH_MAX_BACKLOG
)
2645 ssh_throttle_all(ssh
, 0, bufsize
);
2649 * Connect to specified host and port.
2650 * Returns an error message, or NULL on success.
2651 * Also places the canonical host name into `realhost'. It must be
2652 * freed by the caller.
2654 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2655 char **realhost
, int nodelay
, int keepalive
)
2657 static const struct plug_function_table fn_table
= {
2668 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2669 strcpy(ssh
->savedhost
, host
);
2672 port
= 22; /* default ssh port */
2673 ssh
->savedport
= port
;
2678 logeventf(ssh
, "Looking up host \"%s\"%s", host
,
2679 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV4 ?
" (IPv4)" :
2680 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV6 ?
" (IPv6)" : "")));
2681 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
,
2682 ssh
->cfg
.addressfamily
);
2683 if ((err
= sk_addr_error(addr
)) != NULL
) {
2691 ssh
->fn
= &fn_table
;
2692 ssh
->s
= new_connection(addr
, *realhost
, port
,
2693 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2694 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2696 notify_remote_exit(ssh
->frontend
);
2704 * Throttle or unthrottle the SSH connection.
2706 static void ssh1_throttle(Ssh ssh
, int adjust
)
2708 int old_count
= ssh
->v1_throttle_count
;
2709 ssh
->v1_throttle_count
+= adjust
;
2710 assert(ssh
->v1_throttle_count
>= 0);
2711 if (ssh
->v1_throttle_count
&& !old_count
) {
2712 ssh_set_frozen(ssh
, 1);
2713 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2714 ssh_set_frozen(ssh
, 0);
2719 * Throttle or unthrottle _all_ local data streams (for when sends
2720 * on the SSH connection itself back up).
2722 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2725 struct ssh_channel
*c
;
2727 if (enable
== ssh
->throttled_all
)
2729 ssh
->throttled_all
= enable
;
2730 ssh
->overall_bufsize
= bufsize
;
2733 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2735 case CHAN_MAINSESSION
:
2737 * This is treated separately, outside the switch.
2741 x11_override_throttle(c
->u
.x11
.s
, enable
);
2744 /* Agent channels require no buffer management. */
2747 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2754 * Username and password input, abstracted off into routines
2755 * reusable in several places - even between SSH-1 and SSH-2.
2758 /* Set up a username or password input loop on a given buffer. */
2759 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2761 ssh
->userpass_input_buffer
= buffer
;
2762 ssh
->userpass_input_buflen
= buflen
;
2763 ssh
->userpass_input_bufpos
= 0;
2764 ssh
->userpass_input_echo
= echo
;
2768 * Process some terminal data in the course of username/password
2769 * input. Returns >0 for success (line of input returned in
2770 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2771 * for inconclusive (keep waiting for more input please).
2773 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2778 switch (c
= *in
++) {
2781 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2782 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2787 if (ssh
->userpass_input_bufpos
> 0) {
2788 if (ssh
->userpass_input_echo
)
2789 c_write_str(ssh
, "\b \b");
2790 ssh
->userpass_input_bufpos
--;
2795 while (ssh
->userpass_input_bufpos
> 0) {
2796 if (ssh
->userpass_input_echo
)
2797 c_write_str(ssh
, "\b \b");
2798 ssh
->userpass_input_bufpos
--;
2807 * This simplistic check for printability is disabled
2808 * when we're doing password input, because some people
2809 * have control characters in their passwords.o
2811 if ((!ssh
->userpass_input_echo
||
2812 (c
>= ' ' && c
<= '~') ||
2813 ((unsigned char) c
>= 160))
2814 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2815 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2816 if (ssh
->userpass_input_echo
)
2817 c_write(ssh
, &c
, 1);
2825 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2827 Ssh ssh
= (Ssh
) sshv
;
2829 ssh
->agent_response
= reply
;
2830 ssh
->agent_response_len
= replylen
;
2832 if (ssh
->version
== 1)
2833 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2835 do_ssh2_authconn(ssh
, NULL
, -1, NULL
);
2838 static void ssh_dialog_callback(void *sshv
, int ret
)
2840 Ssh ssh
= (Ssh
) sshv
;
2842 ssh
->user_response
= ret
;
2844 if (ssh
->version
== 1)
2845 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2847 do_ssh2_transport(ssh
, NULL
, -1, NULL
);
2850 * This may have unfrozen the SSH connection, so do a
2853 ssh_process_queued_incoming_data(ssh
);
2856 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2858 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2860 void *sentreply
= reply
;
2863 /* Fake SSH_AGENT_FAILURE. */
2864 sentreply
= "\0\0\0\1\5";
2867 if (ssh
->version
== 2) {
2868 ssh2_add_channel_data(c
, sentreply
, replylen
);
2871 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2872 PKT_INT
, c
->remoteid
,
2875 PKT_DATA
, sentreply
, replylen
,
2884 * Client-initiated disconnection. Send a DISCONNECT if `wire_reason'
2885 * non-NULL, otherwise just close the connection. `client_reason' == NULL
2886 * => log `wire_reason'.
2888 static void ssh_disconnect(Ssh ssh
, char *client_reason
, char *wire_reason
,
2889 int code
, int clean_exit
)
2893 client_reason
= wire_reason
;
2895 error
= dupprintf("Disconnected: %s", client_reason
);
2897 error
= dupstr("Disconnected");
2899 if (ssh
->version
== 1) {
2900 send_packet(ssh
, SSH1_MSG_DISCONNECT
, PKT_STR
, wire_reason
,
2902 } else if (ssh
->version
== 2) {
2903 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
2904 ssh2_pkt_adduint32(pktout
, code
);
2905 ssh2_pkt_addstring(pktout
, wire_reason
);
2906 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
2907 ssh2_pkt_send_noqueue(ssh
, pktout
);
2910 ssh
->close_expected
= TRUE
;
2911 ssh
->clean_exit
= clean_exit
;
2912 ssh_closing((Plug
)ssh
, error
, 0, 0);
2917 * Handle the key exchange and user authentication phases.
2919 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
2920 struct Packet
*pktin
)
2923 unsigned char cookie
[8], *ptr
;
2924 struct RSAKey servkey
, hostkey
;
2925 struct MD5Context md5c
;
2926 struct do_ssh1_login_state
{
2928 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2929 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2930 int tried_publickey
, tried_agent
;
2931 int tis_auth_refused
, ccard_auth_refused
;
2932 unsigned char session_id
[16];
2935 void *publickey_blob
;
2936 int publickey_bloblen
;
2942 unsigned char request
[5], *response
, *p
;
2952 crState(do_ssh1_login_state
);
2954 crBegin(ssh
->do_ssh1_login_crstate
);
2959 if (pktin
->type
!= SSH1_SMSG_PUBLIC_KEY
) {
2960 bombout(("Public key packet not received"));
2964 logevent("Received public keys");
2966 ptr
= ssh_pkt_getdata(pktin
, 8);
2968 bombout(("SSH-1 public key packet stopped before random cookie"));
2971 memcpy(cookie
, ptr
, 8);
2973 if (!ssh1_pkt_getrsakey(pktin
, &servkey
, &s
->keystr1
) ||
2974 !ssh1_pkt_getrsakey(pktin
, &hostkey
, &s
->keystr2
)) {
2975 bombout(("Failed to read SSH-1 public keys from public key packet"));
2980 * Log the host key fingerprint.
2984 logevent("Host key fingerprint is:");
2985 strcpy(logmsg
, " ");
2986 hostkey
.comment
= NULL
;
2987 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2988 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2992 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(pktin
);
2993 s
->supported_ciphers_mask
= ssh_pkt_getuint32(pktin
);
2994 s
->supported_auths_mask
= ssh_pkt_getuint32(pktin
);
2996 ssh
->v1_local_protoflags
=
2997 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2998 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
3001 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
3002 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
3003 MD5Update(&md5c
, cookie
, 8);
3004 MD5Final(s
->session_id
, &md5c
);
3006 for (i
= 0; i
< 32; i
++)
3007 ssh
->session_key
[i
] = random_byte();
3010 * Verify that the `bits' and `bytes' parameters match.
3012 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
3013 servkey
.bits
> servkey
.bytes
* 8) {
3014 bombout(("SSH-1 public keys were badly formatted"));
3018 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
3020 s
->rsabuf
= snewn(s
->len
, unsigned char);
3023 * Verify the host key.
3027 * First format the key into a string.
3029 int len
= rsastr_len(&hostkey
);
3030 char fingerprint
[100];
3031 char *keystr
= snewn(len
, char);
3032 rsastr_fmt(keystr
, &hostkey
);
3033 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
3035 ssh_set_frozen(ssh
, 1);
3036 s
->dlgret
= verify_ssh_host_key(ssh
->frontend
,
3037 ssh
->savedhost
, ssh
->savedport
,
3038 "rsa", keystr
, fingerprint
,
3039 ssh_dialog_callback
, ssh
);
3041 if (s
->dlgret
< 0) {
3045 bombout(("Unexpected data from server while waiting"
3046 " for user host key response"));
3049 } while (pktin
|| inlen
> 0);
3050 s
->dlgret
= ssh
->user_response
;
3052 ssh_set_frozen(ssh
, 0);
3054 if (s
->dlgret
== 0) {
3055 ssh_disconnect(ssh
, "User aborted at host key verification",
3061 for (i
= 0; i
< 32; i
++) {
3062 s
->rsabuf
[i
] = ssh
->session_key
[i
];
3064 s
->rsabuf
[i
] ^= s
->session_id
[i
];
3067 if (hostkey
.bytes
> servkey
.bytes
) {
3068 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
3070 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
3072 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
3074 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
3077 bombout(("SSH-1 public key encryptions failed due to bad formatting"));
3081 logevent("Encrypted session key");
3084 int cipher_chosen
= 0, warn
= 0;
3085 char *cipher_string
= NULL
;
3087 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
3088 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
3089 if (next_cipher
== CIPHER_WARN
) {
3090 /* If/when we choose a cipher, warn about it */
3092 } else if (next_cipher
== CIPHER_AES
) {
3093 /* XXX Probably don't need to mention this. */
3094 logevent("AES not supported in SSH-1, skipping");
3096 switch (next_cipher
) {
3097 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
3098 cipher_string
= "3DES"; break;
3099 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
3100 cipher_string
= "Blowfish"; break;
3101 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
3102 cipher_string
= "single-DES"; break;
3104 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
3108 if (!cipher_chosen
) {
3109 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
3110 bombout(("Server violates SSH-1 protocol by not "
3111 "supporting 3DES encryption"));
3113 /* shouldn't happen */
3114 bombout(("No supported ciphers found"));
3118 /* Warn about chosen cipher if necessary. */
3120 ssh_set_frozen(ssh
, 1);
3121 s
->dlgret
= askalg(ssh
->frontend
, "cipher", cipher_string
,
3122 ssh_dialog_callback
, ssh
);
3123 if (s
->dlgret
< 0) {
3127 bombout(("Unexpected data from server while waiting"
3128 " for user response"));
3131 } while (pktin
|| inlen
> 0);
3132 s
->dlgret
= ssh
->user_response
;
3134 ssh_set_frozen(ssh
, 0);
3135 if (s
->dlgret
== 0) {
3136 ssh_disconnect(ssh
, "User aborted at cipher warning", NULL
,
3143 switch (s
->cipher_type
) {
3144 case SSH_CIPHER_3DES
:
3145 logevent("Using 3DES encryption");
3147 case SSH_CIPHER_DES
:
3148 logevent("Using single-DES encryption");
3150 case SSH_CIPHER_BLOWFISH
:
3151 logevent("Using Blowfish encryption");
3155 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
3156 PKT_CHAR
, s
->cipher_type
,
3157 PKT_DATA
, cookie
, 8,
3158 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
3159 PKT_DATA
, s
->rsabuf
, s
->len
,
3160 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
3162 logevent("Trying to enable encryption...");
3166 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
3167 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
3169 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
3170 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
3171 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
3173 ssh
->crcda_ctx
= crcda_make_context();
3174 logevent("Installing CRC compensation attack detector");
3176 if (servkey
.modulus
) {
3177 sfree(servkey
.modulus
);
3178 servkey
.modulus
= NULL
;
3180 if (servkey
.exponent
) {
3181 sfree(servkey
.exponent
);
3182 servkey
.exponent
= NULL
;
3184 if (hostkey
.modulus
) {
3185 sfree(hostkey
.modulus
);
3186 hostkey
.modulus
= NULL
;
3188 if (hostkey
.exponent
) {
3189 sfree(hostkey
.exponent
);
3190 hostkey
.exponent
= NULL
;
3194 if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3195 bombout(("Encryption not successfully enabled"));
3199 logevent("Successfully started encryption");
3203 if (!*ssh
->cfg
.username
) {
3204 if (ssh_get_line
&& !ssh_getline_pw_only
) {
3205 if (!ssh_get_line("login as: ",
3206 s
->username
, sizeof(s
->username
), FALSE
)) {
3208 * get_line failed to get a username.
3211 ssh_disconnect(ssh
, "No username provided", NULL
, 0, TRUE
);
3215 int ret
; /* need not be kept over crReturn */
3216 c_write_str(ssh
, "login as: ");
3219 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
3221 crWaitUntil(!pktin
);
3222 ret
= process_userpass_input(ssh
, in
, inlen
);
3226 c_write_str(ssh
, "\r\n");
3229 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
3230 s
->username
[sizeof(s
->username
)-1] = '\0';
3233 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
3235 char userlog
[22 + sizeof(s
->username
)];
3236 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
3238 if (flags
& FLAG_INTERACTIVE
&&
3239 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
3240 strcat(userlog
, "\r\n");
3241 c_write_str(ssh
, userlog
);
3248 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
3249 /* We must not attempt PK auth. Pretend we've already tried it. */
3250 s
->tried_publickey
= s
->tried_agent
= 1;
3252 s
->tried_publickey
= s
->tried_agent
= 0;
3254 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
3255 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
3256 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
3257 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
3258 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
3259 s
->publickey_blob
= NULL
;
3261 s
->publickey_blob
= NULL
;
3263 while (pktin
->type
== SSH1_SMSG_FAILURE
) {
3264 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
3266 if (agent_exists() && !s
->tried_agent
) {
3268 * Attempt RSA authentication using Pageant.
3274 logevent("Pageant is running. Requesting keys.");
3276 /* Request the keys held by the agent. */
3277 PUT_32BIT(s
->request
, 1);
3278 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
3279 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
3280 ssh_agent_callback
, ssh
)) {
3284 bombout(("Unexpected data from server while waiting"
3285 " for agent response"));
3288 } while (pktin
|| inlen
> 0);
3289 r
= ssh
->agent_response
;
3290 s
->responselen
= ssh
->agent_response_len
;
3292 s
->response
= (unsigned char *) r
;
3293 if (s
->response
&& s
->responselen
>= 5 &&
3294 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
3295 s
->p
= s
->response
+ 5;
3296 s
->nkeys
= GET_32BIT(s
->p
);
3298 logeventf(ssh
, "Pageant has %d SSH-1 keys", s
->nkeys
);
3299 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
3300 logeventf(ssh
, "Trying Pageant key #%d", s
->keyi
);
3301 if (s
->publickey_blob
&&
3302 !memcmp(s
->p
, s
->publickey_blob
,
3303 s
->publickey_bloblen
)) {
3304 logevent("This key matches configured key file");
3305 s
->tried_publickey
= 1;
3310 do { /* do while (0) to make breaking easy */
3311 n
= ssh1_read_bignum
3312 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3317 n
= ssh1_read_bignum
3318 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3323 if (s
->responselen
- (s
->p
-s
->response
) < 4)
3325 s
->commentlen
= GET_32BIT(s
->p
);
3327 if (s
->responselen
- (s
->p
-s
->response
) <
3330 s
->commentp
= (char *)s
->p
;
3331 s
->p
+= s
->commentlen
;
3335 logevent("Pageant key list packet was truncated");
3339 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3340 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3342 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3343 logevent("Key refused");
3346 logevent("Received RSA challenge");
3347 if ((s
->challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3348 bombout(("Server's RSA challenge was badly formatted"));
3353 char *agentreq
, *q
, *ret
;
3356 len
= 1 + 4; /* message type, bit count */
3357 len
+= ssh1_bignum_length(s
->key
.exponent
);
3358 len
+= ssh1_bignum_length(s
->key
.modulus
);
3359 len
+= ssh1_bignum_length(s
->challenge
);
3360 len
+= 16; /* session id */
3361 len
+= 4; /* response format */
3362 agentreq
= snewn(4 + len
, char);
3363 PUT_32BIT(agentreq
, len
);
3365 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
3366 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
3368 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
3369 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
3370 q
+= ssh1_write_bignum(q
, s
->challenge
);
3371 memcpy(q
, s
->session_id
, 16);
3373 PUT_32BIT(q
, 1); /* response format */
3374 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
3375 ssh_agent_callback
, ssh
)) {
3380 bombout(("Unexpected data from server"
3381 " while waiting for agent"
3385 } while (pktin
|| inlen
> 0);
3386 vret
= ssh
->agent_response
;
3387 retlen
= ssh
->agent_response_len
;
3392 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
3393 logevent("Sending Pageant's response");
3394 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3395 PKT_DATA
, ret
+ 5, 16,
3399 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
3401 ("Pageant's response accepted");
3402 if (flags
& FLAG_VERBOSE
) {
3403 c_write_str(ssh
, "Authenticated using"
3405 c_write(ssh
, s
->commentp
,
3407 c_write_str(ssh
, "\" from agent\r\n");
3412 ("Pageant's response not accepted");
3415 ("Pageant failed to answer challenge");
3419 logevent("No reply received from Pageant");
3422 freebn(s
->key
.exponent
);
3423 freebn(s
->key
.modulus
);
3424 freebn(s
->challenge
);
3433 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
3434 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
3436 if (ssh
->cfg
.try_tis_auth
&&
3437 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3438 !s
->tis_auth_refused
) {
3439 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3440 logevent("Requested TIS authentication");
3441 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3443 if (pktin
->type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3444 logevent("TIS authentication declined");
3445 if (flags
& FLAG_INTERACTIVE
)
3446 c_write_str(ssh
, "TIS authentication refused.\r\n");
3447 s
->tis_auth_refused
= 1;
3453 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3455 bombout(("TIS challenge packet was badly formed"));
3458 c_write_str(ssh
, "Using TIS authentication.\r\n");
3459 logevent("Received TIS challenge");
3460 if (challengelen
> sizeof(s
->prompt
) - 1)
3461 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3462 memcpy(s
->prompt
, challenge
, challengelen
);
3463 /* Prompt heuristic comes from OpenSSH */
3464 strncpy(s
->prompt
+ challengelen
,
3465 memchr(s
->prompt
, '\n', challengelen
) ?
3466 "": "\r\nResponse: ",
3467 (sizeof s
->prompt
) - challengelen
);
3468 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
3471 if (ssh
->cfg
.try_tis_auth
&&
3472 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3473 !s
->ccard_auth_refused
) {
3474 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3475 logevent("Requested CryptoCard authentication");
3476 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3478 if (pktin
->type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3479 logevent("CryptoCard authentication declined");
3480 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3481 s
->ccard_auth_refused
= 1;
3487 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3489 bombout(("CryptoCard challenge packet was badly formed"));
3492 c_write_str(ssh
, "Using CryptoCard authentication.\r\n");
3493 logevent("Received CryptoCard challenge");
3494 if (challengelen
> sizeof(s
->prompt
) - 1)
3495 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3496 memcpy(s
->prompt
, challenge
, challengelen
);
3497 strncpy(s
->prompt
+ challengelen
,
3498 memchr(s
->prompt
, '\n', challengelen
) ?
3499 "" : "\r\nResponse: ",
3500 sizeof(s
->prompt
) - challengelen
);
3501 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
3504 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3505 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
3506 s
->username
, ssh
->savedhost
);
3508 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3509 char *comment
= NULL
;
3511 if (flags
& FLAG_VERBOSE
)
3512 c_write_str(ssh
, "Trying public key authentication.\r\n");
3513 logeventf(ssh
, "Trying public key \"%s\"",
3514 filename_to_str(&ssh
->cfg
.keyfile
));
3515 type
= key_type(&ssh
->cfg
.keyfile
);
3516 if (type
!= SSH_KEYTYPE_SSH1
) {
3517 char *msg
= dupprintf("Key is of wrong type (%s)",
3518 key_type_to_str(type
));
3520 c_write_str(ssh
, msg
);
3521 c_write_str(ssh
, "\r\n");
3523 s
->tried_publickey
= 1;
3526 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
3527 if (flags
& FLAG_VERBOSE
)
3528 c_write_str(ssh
, "No passphrase required.\r\n");
3531 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
3536 * Show password prompt, having first obtained it via a TIS
3537 * or CryptoCard exchange if we're doing TIS or CryptoCard
3541 if (!ssh_get_line(s
->prompt
, s
->password
,
3542 sizeof(s
->password
), TRUE
)) {
3544 * get_line failed to get a password (for example
3545 * because one was supplied on the command line
3546 * which has already failed to work). Terminate.
3548 ssh_disconnect(ssh
, NULL
, "Unable to authenticate", 0, FALSE
);
3552 /* Prompt may have come from server. We've munged it a bit, so
3553 * we know it to be zero-terminated at least once. */
3554 int ret
; /* need not be saved over crReturn */
3555 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3558 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3560 crWaitUntil(!pktin
);
3561 ret
= process_userpass_input(ssh
, in
, inlen
);
3565 c_write_str(ssh
, "\r\n");
3569 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3571 * Try public key authentication with the specified
3574 s
->tried_publickey
= 1;
3577 const char *error
= NULL
;
3578 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3581 c_write_str(ssh
, "Couldn't load private key from ");
3582 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3583 c_write_str(ssh
, " (");
3584 c_write_str(ssh
, error
);
3585 c_write_str(ssh
, ").\r\n");
3586 continue; /* go and try password */
3589 c_write_str(ssh
, "Wrong passphrase.\r\n");
3590 s
->tried_publickey
= 0;
3591 continue; /* try again */
3596 * Send a public key attempt.
3598 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3599 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3602 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3603 c_write_str(ssh
, "Server refused our public key.\r\n");
3604 continue; /* go and try password */
3606 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3607 bombout(("Bizarre response to offer of public key"));
3613 unsigned char buffer
[32];
3614 Bignum challenge
, response
;
3616 if ((challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3617 bombout(("Server's RSA challenge was badly formatted"));
3620 response
= rsadecrypt(challenge
, &s
->key
);
3621 freebn(s
->key
.private_exponent
);/* burn the evidence */
3623 for (i
= 0; i
< 32; i
++) {
3624 buffer
[i
] = bignum_byte(response
, 31 - i
);
3628 MD5Update(&md5c
, buffer
, 32);
3629 MD5Update(&md5c
, s
->session_id
, 16);
3630 MD5Final(buffer
, &md5c
);
3632 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3633 PKT_DATA
, buffer
, 16, PKT_END
);
3640 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3641 if (flags
& FLAG_VERBOSE
)
3642 c_write_str(ssh
, "Failed to authenticate with"
3643 " our public key.\r\n");
3644 continue; /* go and try password */
3645 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3646 bombout(("Bizarre response to RSA authentication response"));
3650 break; /* we're through! */
3652 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3654 * Defence against traffic analysis: we send a
3655 * whole bunch of packets containing strings of
3656 * different lengths. One of these strings is the
3657 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3658 * The others are all random data in
3659 * SSH1_MSG_IGNORE packets. This way a passive
3660 * listener can't tell which is the password, and
3661 * hence can't deduce the password length.
3663 * Anybody with a password length greater than 16
3664 * bytes is going to have enough entropy in their
3665 * password that a listener won't find it _that_
3666 * much help to know how long it is. So what we'll
3669 * - if password length < 16, we send 15 packets
3670 * containing string lengths 1 through 15
3672 * - otherwise, we let N be the nearest multiple
3673 * of 8 below the password length, and send 8
3674 * packets containing string lengths N through
3675 * N+7. This won't obscure the order of
3676 * magnitude of the password length, but it will
3677 * introduce a bit of extra uncertainty.
3679 * A few servers (the old 1.2.18 through 1.2.22)
3680 * can't deal with SSH1_MSG_IGNORE. For these
3681 * servers, we need an alternative defence. We make
3682 * use of the fact that the password is interpreted
3683 * as a C string: so we can append a NUL, then some
3686 * One server (a Cisco one) can deal with neither
3687 * SSH1_MSG_IGNORE _nor_ a padded password string.
3688 * For this server we are left with no defences
3689 * against password length sniffing.
3691 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3693 * The server can deal with SSH1_MSG_IGNORE, so
3694 * we can use the primary defence.
3696 int bottom
, top
, pwlen
, i
;
3699 pwlen
= strlen(s
->password
);
3701 bottom
= 0; /* zero length passwords are OK! :-) */
3704 bottom
= pwlen
& ~7;
3708 assert(pwlen
>= bottom
&& pwlen
<= top
);
3710 randomstr
= snewn(top
+ 1, char);
3712 for (i
= bottom
; i
<= top
; i
++) {
3714 defer_packet(ssh
, s
->pwpkt_type
,
3715 PKTT_PASSWORD
, PKT_STR
, s
->password
,
3716 PKTT_OTHER
, PKT_END
);
3718 for (j
= 0; j
< i
; j
++) {
3720 randomstr
[j
] = random_byte();
3721 } while (randomstr
[j
] == '\0');
3723 randomstr
[i
] = '\0';
3724 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3725 PKT_STR
, randomstr
, PKT_END
);
3728 logevent("Sending password with camouflage packets");
3729 ssh_pkt_defersend(ssh
);
3732 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3734 * The server can't deal with SSH1_MSG_IGNORE
3735 * but can deal with padded passwords, so we
3736 * can use the secondary defence.
3742 len
= strlen(s
->password
);
3743 if (len
< sizeof(string
)) {
3745 strcpy(string
, s
->password
);
3746 len
++; /* cover the zero byte */
3747 while (len
< sizeof(string
)) {
3748 string
[len
++] = (char) random_byte();
3753 logevent("Sending length-padded password");
3754 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3755 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3756 PKTT_OTHER
, PKT_END
);
3759 * The server has _both_
3760 * BUG_CHOKES_ON_SSH1_IGNORE and
3761 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3762 * therefore nothing we can do.
3765 len
= strlen(s
->password
);
3766 logevent("Sending unpadded password");
3767 send_packet(ssh
, s
->pwpkt_type
,
3768 PKTT_PASSWORD
, PKT_INT
, len
,
3769 PKT_DATA
, s
->password
, len
,
3770 PKTT_OTHER
, PKT_END
);
3773 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3774 PKT_STR
, s
->password
, PKTT_OTHER
, PKT_END
);
3777 logevent("Sent password");
3778 memset(s
->password
, 0, strlen(s
->password
));
3780 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3781 if (flags
& FLAG_VERBOSE
)
3782 c_write_str(ssh
, "Access denied\r\n");
3783 logevent("Authentication refused");
3784 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3785 bombout(("Strange packet received, type %d", pktin
->type
));
3790 logevent("Authentication successful");
3795 void sshfwd_close(struct ssh_channel
*c
)
3799 if (ssh
->state
== SSH_STATE_CLOSED
)
3802 if (c
&& !c
->closes
) {
3804 * If halfopen is true, we have sent
3805 * CHANNEL_OPEN for this channel, but it hasn't even been
3806 * acknowledged by the server. So we must set a close flag
3807 * on it now, and then when the server acks the channel
3808 * open, we can close it then.
3811 if (ssh
->version
== 1) {
3812 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3815 struct Packet
*pktout
;
3816 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3817 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
3818 ssh2_pkt_send(ssh
, pktout
);
3821 c
->closes
= 1; /* sent MSG_CLOSE */
3822 if (c
->type
== CHAN_X11
) {
3824 logevent("Forwarded X11 connection terminated");
3825 } else if (c
->type
== CHAN_SOCKDATA
||
3826 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3828 logevent("Forwarded port closed");
3833 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3837 if (ssh
->state
== SSH_STATE_CLOSED
)
3840 if (ssh
->version
== 1) {
3841 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3842 PKT_INT
, c
->remoteid
,
3844 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3845 PKTT_OTHER
, PKT_END
);
3847 * In SSH-1 we can return 0 here - implying that forwarded
3848 * connections are never individually throttled - because
3849 * the only circumstance that can cause throttling will be
3850 * the whole SSH connection backing up, in which case
3851 * _everything_ will be throttled as a whole.
3855 ssh2_add_channel_data(c
, buf
, len
);
3856 return ssh2_try_send(c
);
3860 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3864 if (ssh
->state
== SSH_STATE_CLOSED
)
3867 if (ssh
->version
== 1) {
3868 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3869 c
->v
.v1
.throttling
= 0;
3870 ssh1_throttle(ssh
, -1);
3873 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3877 static void ssh_queueing_handler(Ssh ssh
, struct Packet
*pktin
)
3879 struct queued_handler
*qh
= ssh
->qhead
;
3883 assert(pktin
->type
== qh
->msg1
|| pktin
->type
== qh
->msg2
);
3886 assert(ssh
->packet_dispatch
[qh
->msg1
] == ssh_queueing_handler
);
3887 ssh
->packet_dispatch
[qh
->msg1
] = NULL
;
3890 assert(ssh
->packet_dispatch
[qh
->msg2
] == ssh_queueing_handler
);
3891 ssh
->packet_dispatch
[qh
->msg2
] = NULL
;
3895 ssh
->qhead
= qh
->next
;
3897 if (ssh
->qhead
->msg1
> 0) {
3898 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg1
] == NULL
);
3899 ssh
->packet_dispatch
[ssh
->qhead
->msg1
] = ssh_queueing_handler
;
3901 if (ssh
->qhead
->msg2
> 0) {
3902 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg2
] == NULL
);
3903 ssh
->packet_dispatch
[ssh
->qhead
->msg2
] = ssh_queueing_handler
;
3906 ssh
->qhead
= ssh
->qtail
= NULL
;
3907 ssh
->packet_dispatch
[pktin
->type
] = NULL
;
3910 qh
->handler(ssh
, pktin
, qh
->ctx
);
3915 static void ssh_queue_handler(Ssh ssh
, int msg1
, int msg2
,
3916 chandler_fn_t handler
, void *ctx
)
3918 struct queued_handler
*qh
;
3920 qh
= snew(struct queued_handler
);
3923 qh
->handler
= handler
;
3927 if (ssh
->qtail
== NULL
) {
3931 assert(ssh
->packet_dispatch
[qh
->msg1
] == NULL
);
3932 ssh
->packet_dispatch
[qh
->msg1
] = ssh_queueing_handler
;
3935 assert(ssh
->packet_dispatch
[qh
->msg2
] == NULL
);
3936 ssh
->packet_dispatch
[qh
->msg2
] = ssh_queueing_handler
;
3939 ssh
->qtail
->next
= qh
;
3944 static void ssh_rportfwd_succfail(Ssh ssh
, struct Packet
*pktin
, void *ctx
)
3946 struct ssh_rportfwd
*rpf
, *pf
= (struct ssh_rportfwd
*)ctx
;
3948 if (pktin
->type
== (ssh
->version
== 1 ? SSH1_SMSG_SUCCESS
:
3949 SSH2_MSG_REQUEST_SUCCESS
)) {
3950 logeventf(ssh
, "Remote port forwarding from %s enabled",
3953 logeventf(ssh
, "Remote port forwarding from %s refused",
3956 rpf
= del234(ssh
->rportfwds
, pf
);
3962 static void ssh_setup_portfwd(Ssh ssh
, const Config
*cfg
)
3964 const char *portfwd_strptr
= cfg
->portfwd
;
3965 struct ssh_portfwd
*epf
;
3968 if (!ssh
->portfwds
) {
3969 ssh
->portfwds
= newtree234(ssh_portcmp
);
3972 * Go through the existing port forwardings and tag them
3973 * with status==DESTROY. Any that we want to keep will be
3974 * re-enabled (status==KEEP) as we go through the
3975 * configuration and find out which bits are the same as
3978 struct ssh_portfwd
*epf
;
3980 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3981 epf
->status
= DESTROY
;
3984 while (*portfwd_strptr
) {
3985 char address_family
, type
;
3986 int sport
,dport
,sserv
,dserv
;
3987 char sports
[256], dports
[256], saddr
[256], host
[256];
3990 address_family
= 'A';
3992 if (*portfwd_strptr
== 'A' ||
3993 *portfwd_strptr
== '4' ||
3994 *portfwd_strptr
== '6')
3995 address_family
= *portfwd_strptr
++;
3996 if (*portfwd_strptr
== 'L' ||
3997 *portfwd_strptr
== 'R' ||
3998 *portfwd_strptr
== 'D')
3999 type
= *portfwd_strptr
++;
4004 while (*portfwd_strptr
&& *portfwd_strptr
!= '\t') {
4005 if (*portfwd_strptr
== ':') {
4007 * We've seen a colon in the middle of the
4008 * source port number. This means that
4009 * everything we've seen until now is the
4010 * source _address_, so we'll move it into
4011 * saddr and start sports from the beginning
4016 if (ssh
->version
== 1 && type
== 'R') {
4017 logeventf(ssh
, "SSH-1 cannot handle remote source address "
4018 "spec \"%s\"; ignoring", sports
);
4020 strcpy(saddr
, sports
);
4023 if (n
< lenof(sports
)-1) sports
[n
++] = *portfwd_strptr
++;
4027 if (*portfwd_strptr
== '\t')
4030 while (*portfwd_strptr
&& *portfwd_strptr
!= ':') {
4031 if (n
< lenof(host
)-1) host
[n
++] = *portfwd_strptr
++;
4034 if (*portfwd_strptr
== ':')
4037 while (*portfwd_strptr
) {
4038 if (n
< lenof(dports
)-1) dports
[n
++] = *portfwd_strptr
++;
4042 dport
= atoi(dports
);
4046 dport
= net_service_lookup(dports
);
4048 logeventf(ssh
, "Service lookup failed for destination"
4049 " port \"%s\"", dports
);
4053 while (*portfwd_strptr
) portfwd_strptr
++;
4057 portfwd_strptr
++; /* eat the NUL and move to next one */
4059 sport
= atoi(sports
);
4063 sport
= net_service_lookup(sports
);
4065 logeventf(ssh
, "Service lookup failed for source"
4066 " port \"%s\"", sports
);
4069 if (sport
&& dport
) {
4070 /* Set up a description of the source port. */
4071 struct ssh_portfwd
*pfrec
, *epfrec
;
4073 pfrec
= snew(struct ssh_portfwd
);
4075 pfrec
->saddr
= *saddr ?
dupstr(saddr
) : NULL
;
4076 pfrec
->sserv
= sserv ?
dupstr(sports
) : NULL
;
4077 pfrec
->sport
= sport
;
4078 pfrec
->daddr
= *host ?
dupstr(host
) : NULL
;
4079 pfrec
->dserv
= dserv ?
dupstr(dports
) : NULL
;
4080 pfrec
->dport
= dport
;
4081 pfrec
->local
= NULL
;
4082 pfrec
->remote
= NULL
;
4083 pfrec
->addressfamily
= (address_family
== '4' ? ADDRTYPE_IPV4
:
4084 address_family
== '6' ? ADDRTYPE_IPV6
:
4087 epfrec
= add234(ssh
->portfwds
, pfrec
);
4088 if (epfrec
!= pfrec
) {
4090 * We already have a port forwarding with precisely
4091 * these parameters. Hence, no need to do anything;
4092 * simply tag the existing one as KEEP.
4094 epfrec
->status
= KEEP
;
4095 free_portfwd(pfrec
);
4097 pfrec
->status
= CREATE
;
4103 * Now go through and destroy any port forwardings which were
4106 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
4107 if (epf
->status
== DESTROY
) {
4110 message
= dupprintf("%s port forwarding from %s%s%d",
4111 epf
->type
== 'L' ?
"local" :
4112 epf
->type
== 'R' ?
"remote" : "dynamic",
4113 epf
->saddr ? epf
->saddr
: "",
4114 epf
->saddr ?
":" : "",
4117 if (epf
->type
!= 'D') {
4118 char *msg2
= dupprintf("%s to %s:%d", message
,
4119 epf
->daddr
, epf
->dport
);
4124 logeventf(ssh
, "Cancelling %s", message
);
4128 struct ssh_rportfwd
*rpf
= epf
->remote
;
4129 struct Packet
*pktout
;
4132 * Cancel the port forwarding at the server
4135 if (ssh
->version
== 1) {
4137 * We cannot cancel listening ports on the
4138 * server side in SSH-1! There's no message
4139 * to support it. Instead, we simply remove
4140 * the rportfwd record from the local end
4141 * so that any connections the server tries
4142 * to make on it are rejected.
4145 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
4146 ssh2_pkt_addstring(pktout
, "cancel-tcpip-forward");
4147 ssh2_pkt_addbool(pktout
, 0);/* _don't_ want reply */
4149 ssh2_pkt_addstring(pktout
, epf
->saddr
);
4150 } else if (ssh
->cfg
.rport_acceptall
) {
4151 /* XXX: ssh->cfg.rport_acceptall may not represent
4152 * what was used to open the original connection,
4153 * since it's reconfigurable. */
4154 ssh2_pkt_addstring(pktout
, "0.0.0.0");
4156 ssh2_pkt_addstring(pktout
, "127.0.0.1");
4158 ssh2_pkt_adduint32(pktout
, epf
->sport
);
4159 ssh2_pkt_send(ssh
, pktout
);
4162 del234(ssh
->rportfwds
, rpf
);
4164 } else if (epf
->local
) {
4165 pfd_terminate(epf
->local
);
4168 delpos234(ssh
->portfwds
, i
);
4170 i
--; /* so we don't skip one in the list */
4174 * And finally, set up any new port forwardings (status==CREATE).
4176 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
4177 if (epf
->status
== CREATE
) {
4178 char *sportdesc
, *dportdesc
;
4179 sportdesc
= dupprintf("%s%s%s%s%d%s",
4180 epf
->saddr ? epf
->saddr
: "",
4181 epf
->saddr ?
":" : "",
4182 epf
->sserv ? epf
->sserv
: "",
4183 epf
->sserv ?
"(" : "",
4185 epf
->sserv ?
")" : "");
4186 if (epf
->type
== 'D') {
4189 dportdesc
= dupprintf("%s:%s%s%d%s",
4191 epf
->dserv ? epf
->dserv
: "",
4192 epf
->dserv ?
"(" : "",
4194 epf
->dserv ?
")" : "");
4197 if (epf
->type
== 'L') {
4198 const char *err
= pfd_addforward(epf
->daddr
, epf
->dport
,
4199 epf
->saddr
, epf
->sport
,
4202 epf
->addressfamily
);
4204 logeventf(ssh
, "Local %sport %s forwarding to %s%s%s",
4205 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
4206 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
4207 sportdesc
, dportdesc
,
4208 err ?
" failed: " : "", err ? err
: "");
4209 } else if (epf
->type
== 'D') {
4210 const char *err
= pfd_addforward(NULL
, -1,
4211 epf
->saddr
, epf
->sport
,
4214 epf
->addressfamily
);
4216 logeventf(ssh
, "Local %sport %s SOCKS dynamic forwarding%s%s",
4217 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
4218 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
4220 err ?
" failed: " : "", err ? err
: "");
4222 struct ssh_rportfwd
*pf
;
4225 * Ensure the remote port forwardings tree exists.
4227 if (!ssh
->rportfwds
) {
4228 if (ssh
->version
== 1)
4229 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
4231 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
4234 pf
= snew(struct ssh_rportfwd
);
4235 strncpy(pf
->dhost
, epf
->daddr
, lenof(pf
->dhost
)-1);
4236 pf
->dhost
[lenof(pf
->dhost
)-1] = '\0';
4237 pf
->dport
= epf
->dport
;
4238 pf
->sport
= epf
->sport
;
4239 if (add234(ssh
->rportfwds
, pf
) != pf
) {
4240 logeventf(ssh
, "Duplicate remote port forwarding to %s:%d",
4241 epf
->daddr
, epf
->dport
);
4244 logeventf(ssh
, "Requesting remote port %s"
4245 " forward to %s", sportdesc
, dportdesc
);
4247 pf
->sportdesc
= sportdesc
;
4252 if (ssh
->version
== 1) {
4253 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
4254 PKT_INT
, epf
->sport
,
4255 PKT_STR
, epf
->daddr
,
4256 PKT_INT
, epf
->dport
,
4258 ssh_queue_handler(ssh
, SSH1_SMSG_SUCCESS
,
4260 ssh_rportfwd_succfail
, pf
);
4262 struct Packet
*pktout
;
4263 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
4264 ssh2_pkt_addstring(pktout
, "tcpip-forward");
4265 ssh2_pkt_addbool(pktout
, 1);/* want reply */
4267 ssh2_pkt_addstring(pktout
, epf
->saddr
);
4268 } else if (cfg
->rport_acceptall
) {
4269 ssh2_pkt_addstring(pktout
, "0.0.0.0");
4271 ssh2_pkt_addstring(pktout
, "127.0.0.1");
4273 ssh2_pkt_adduint32(pktout
, epf
->sport
);
4274 ssh2_pkt_send(ssh
, pktout
);
4276 ssh_queue_handler(ssh
, SSH2_MSG_REQUEST_SUCCESS
,
4277 SSH2_MSG_REQUEST_FAILURE
,
4278 ssh_rportfwd_succfail
, pf
);
4287 static void ssh1_smsg_stdout_stderr_data(Ssh ssh
, struct Packet
*pktin
)
4290 int stringlen
, bufsize
;
4292 ssh_pkt_getstring(pktin
, &string
, &stringlen
);
4293 if (string
== NULL
) {
4294 bombout(("Incoming terminal data packet was badly formed"));
4298 bufsize
= from_backend(ssh
->frontend
, pktin
->type
== SSH1_SMSG_STDERR_DATA
,
4300 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4301 ssh
->v1_stdout_throttling
= 1;
4302 ssh1_throttle(ssh
, +1);
4306 static void ssh1_smsg_x11_open(Ssh ssh
, struct Packet
*pktin
)
4308 /* Remote side is trying to open a channel to talk to our
4309 * X-Server. Give them back a local channel number. */
4310 struct ssh_channel
*c
;
4311 int remoteid
= ssh_pkt_getuint32(pktin
);
4313 logevent("Received X11 connect request");
4314 /* Refuse if X11 forwarding is disabled. */
4315 if (!ssh
->X11_fwd_enabled
) {
4316 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4317 PKT_INT
, remoteid
, PKT_END
);
4318 logevent("Rejected X11 connect request");
4320 c
= snew(struct ssh_channel
);
4323 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
4324 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
4325 logevent("Opening X11 forward connection failed");
4327 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4328 PKT_INT
, remoteid
, PKT_END
);
4331 ("Opening X11 forward connection succeeded");
4332 c
->remoteid
= remoteid
;
4333 c
->halfopen
= FALSE
;
4334 c
->localid
= alloc_channel_id(ssh
);
4336 c
->v
.v1
.throttling
= 0;
4337 c
->type
= CHAN_X11
; /* identify channel type */
4338 add234(ssh
->channels
, c
);
4339 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4340 PKT_INT
, c
->remoteid
, PKT_INT
,
4341 c
->localid
, PKT_END
);
4342 logevent("Opened X11 forward channel");
4347 static void ssh1_smsg_agent_open(Ssh ssh
, struct Packet
*pktin
)
4349 /* Remote side is trying to open a channel to talk to our
4350 * agent. Give them back a local channel number. */
4351 struct ssh_channel
*c
;
4352 int remoteid
= ssh_pkt_getuint32(pktin
);
4354 /* Refuse if agent forwarding is disabled. */
4355 if (!ssh
->agentfwd_enabled
) {
4356 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4357 PKT_INT
, remoteid
, PKT_END
);
4359 c
= snew(struct ssh_channel
);
4361 c
->remoteid
= remoteid
;
4362 c
->halfopen
= FALSE
;
4363 c
->localid
= alloc_channel_id(ssh
);
4365 c
->v
.v1
.throttling
= 0;
4366 c
->type
= CHAN_AGENT
; /* identify channel type */
4367 c
->u
.a
.lensofar
= 0;
4368 add234(ssh
->channels
, c
);
4369 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4370 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
4375 static void ssh1_msg_port_open(Ssh ssh
, struct Packet
*pktin
)
4377 /* Remote side is trying to open a channel to talk to a
4378 * forwarded port. Give them back a local channel number. */
4379 struct ssh_channel
*c
;
4380 struct ssh_rportfwd pf
, *pfp
;
4385 c
= snew(struct ssh_channel
);
4388 remoteid
= ssh_pkt_getuint32(pktin
);
4389 ssh_pkt_getstring(pktin
, &host
, &hostsize
);
4390 port
= ssh_pkt_getuint32(pktin
);
4392 if (hostsize
>= lenof(pf
.dhost
))
4393 hostsize
= lenof(pf
.dhost
)-1;
4394 memcpy(pf
.dhost
, host
, hostsize
);
4395 pf
.dhost
[hostsize
] = '\0';
4397 pfp
= find234(ssh
->rportfwds
, &pf
, NULL
);
4400 logeventf(ssh
, "Rejected remote port open request for %s:%d",
4402 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4403 PKT_INT
, remoteid
, PKT_END
);
4405 logeventf(ssh
, "Received remote port open request for %s:%d",
4407 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
4408 c
, &ssh
->cfg
, pfp
->pfrec
->addressfamily
);
4410 logeventf(ssh
, "Port open failed: %s", e
);
4412 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4413 PKT_INT
, remoteid
, PKT_END
);
4415 c
->remoteid
= remoteid
;
4416 c
->halfopen
= FALSE
;
4417 c
->localid
= alloc_channel_id(ssh
);
4419 c
->v
.v1
.throttling
= 0;
4420 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
4421 add234(ssh
->channels
, c
);
4422 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4423 PKT_INT
, c
->remoteid
, PKT_INT
,
4424 c
->localid
, PKT_END
);
4425 logevent("Forwarded port opened successfully");
4430 static void ssh1_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
4432 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4433 unsigned int localid
= ssh_pkt_getuint32(pktin
);
4434 struct ssh_channel
*c
;
4436 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4437 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4438 c
->remoteid
= localid
;
4439 c
->halfopen
= FALSE
;
4440 c
->type
= CHAN_SOCKDATA
;
4441 c
->v
.v1
.throttling
= 0;
4442 pfd_confirm(c
->u
.pfd
.s
);
4445 if (c
&& c
->closes
) {
4447 * We have a pending close on this channel,
4448 * which we decided on before the server acked
4449 * the channel open. So now we know the
4450 * remoteid, we can close it again.
4452 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
4453 PKT_INT
, c
->remoteid
, PKT_END
);
4457 static void ssh1_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
4459 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4460 struct ssh_channel
*c
;
4462 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4463 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4464 logevent("Forwarded connection refused by server");
4465 pfd_close(c
->u
.pfd
.s
);
4466 del234(ssh
->channels
, c
);
4471 static void ssh1_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
4473 /* Remote side closes a channel. */
4474 unsigned i
= ssh_pkt_getuint32(pktin
);
4475 struct ssh_channel
*c
;
4476 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4477 if (c
&& !c
->halfopen
) {
4480 (pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
4482 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
4483 logevent("Forwarded X11 connection terminated");
4484 assert(c
->u
.x11
.s
!= NULL
);
4485 x11_close(c
->u
.x11
.s
);
4488 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
4489 logevent("Forwarded port closed");
4490 assert(c
->u
.pfd
.s
!= NULL
);
4491 pfd_close(c
->u
.pfd
.s
);
4495 c
->closes
|= (closetype
<< 2); /* seen this message */
4496 if (!(c
->closes
& closetype
)) {
4497 send_packet(ssh
, pktin
->type
, PKT_INT
, c
->remoteid
,
4499 c
->closes
|= closetype
; /* sent it too */
4502 if (c
->closes
== 15) {
4503 del234(ssh
->channels
, c
);
4507 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4508 pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
4509 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
4514 static void ssh1_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
4516 /* Data sent down one of our channels. */
4517 int i
= ssh_pkt_getuint32(pktin
);
4520 struct ssh_channel
*c
;
4522 ssh_pkt_getstring(pktin
, &p
, &len
);
4524 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4529 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
4532 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
4535 /* Data for an agent message. Buffer it. */
4537 if (c
->u
.a
.lensofar
< 4) {
4538 unsigned int l
= min(4 - c
->u
.a
.lensofar
, len
);
4539 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
4543 c
->u
.a
.lensofar
+= l
;
4545 if (c
->u
.a
.lensofar
== 4) {
4547 4 + GET_32BIT(c
->u
.a
.msglen
);
4548 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
4550 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
4552 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
4554 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
4556 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
4560 c
->u
.a
.lensofar
+= l
;
4562 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
4565 if (agent_query(c
->u
.a
.message
,
4568 ssh_agentf_callback
, c
))
4569 ssh_agentf_callback(c
, reply
, replylen
);
4570 sfree(c
->u
.a
.message
);
4571 c
->u
.a
.lensofar
= 0;
4574 bufsize
= 0; /* agent channels never back up */
4577 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4578 c
->v
.v1
.throttling
= 1;
4579 ssh1_throttle(ssh
, +1);
4584 static void ssh1_smsg_exit_status(Ssh ssh
, struct Packet
*pktin
)
4586 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
4587 logeventf(ssh
, "Server sent command exit status %d", ssh
->exitcode
);
4588 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
4590 * In case `helpful' firewalls or proxies tack
4591 * extra human-readable text on the end of the
4592 * session which we might mistake for another
4593 * encrypted packet, we close the session once
4594 * we've sent EXIT_CONFIRMATION.
4596 ssh_disconnect(ssh
, NULL
, NULL
, 0, TRUE
);
4599 /* Helper function to deal with sending tty modes for REQUEST_PTY */
4600 static void ssh1_send_ttymode(void *data
, char *mode
, char *val
)
4602 struct Packet
*pktout
= (struct Packet
*)data
;
4604 unsigned int arg
= 0;
4605 while (strcmp(mode
, ssh_ttymodes
[i
].mode
) != 0) i
++;
4606 if (i
== lenof(ssh_ttymodes
)) return;
4607 switch (ssh_ttymodes
[i
].type
) {
4609 arg
= ssh_tty_parse_specchar(val
);
4612 arg
= ssh_tty_parse_boolean(val
);
4615 ssh2_pkt_addbyte(pktout
, ssh_ttymodes
[i
].opcode
);
4616 ssh2_pkt_addbyte(pktout
, arg
);
4620 static void do_ssh1_connection(Ssh ssh
, unsigned char *in
, int inlen
,
4621 struct Packet
*pktin
)
4623 crBegin(ssh
->do_ssh1_connection_crstate
);
4625 ssh
->packet_dispatch
[SSH1_SMSG_STDOUT_DATA
] =
4626 ssh
->packet_dispatch
[SSH1_SMSG_STDERR_DATA
] =
4627 ssh1_smsg_stdout_stderr_data
;
4629 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
] =
4630 ssh1_msg_channel_open_confirmation
;
4631 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_FAILURE
] =
4632 ssh1_msg_channel_open_failure
;
4633 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE
] =
4634 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
] =
4635 ssh1_msg_channel_close
;
4636 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_DATA
] = ssh1_msg_channel_data
;
4637 ssh
->packet_dispatch
[SSH1_SMSG_EXIT_STATUS
] = ssh1_smsg_exit_status
;
4639 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
4640 logevent("Requesting agent forwarding");
4641 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
4645 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4646 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4647 bombout(("Protocol confusion"));
4649 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4650 logevent("Agent forwarding refused");
4652 logevent("Agent forwarding enabled");
4653 ssh
->agentfwd_enabled
= TRUE
;
4654 ssh
->packet_dispatch
[SSH1_SMSG_AGENT_OPEN
] = ssh1_smsg_agent_open
;
4658 if (ssh
->cfg
.x11_forward
) {
4659 char proto
[20], data
[64];
4660 logevent("Requesting X11 forwarding");
4661 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
4662 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
4663 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
4665 * Note that while we blank the X authentication data here, we don't
4666 * take any special action to blank the start of an X11 channel,
4667 * so using MIT-MAGIC-COOKIE-1 and actually opening an X connection
4668 * without having session blanking enabled is likely to leak your
4669 * cookie into the log.
4671 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
4672 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4674 PKTT_PASSWORD
, PKT_STR
, data
, PKTT_OTHER
,
4675 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
4678 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4680 PKTT_PASSWORD
, PKT_STR
, data
, PKTT_OTHER
, PKT_END
);
4685 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4686 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4687 bombout(("Protocol confusion"));
4689 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4690 logevent("X11 forwarding refused");
4692 logevent("X11 forwarding enabled");
4693 ssh
->X11_fwd_enabled
= TRUE
;
4694 ssh
->packet_dispatch
[SSH1_SMSG_X11_OPEN
] = ssh1_smsg_x11_open
;
4698 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
4699 ssh
->packet_dispatch
[SSH1_MSG_PORT_OPEN
] = ssh1_msg_port_open
;
4701 if (!ssh
->cfg
.nopty
) {
4703 /* Unpick the terminal-speed string. */
4704 /* XXX perhaps we should allow no speeds to be sent. */
4705 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
4706 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
4707 /* Send the pty request. */
4708 pkt
= ssh1_pkt_init(SSH1_CMSG_REQUEST_PTY
);
4709 ssh_pkt_addstring(pkt
, ssh
->cfg
.termtype
);
4710 ssh_pkt_adduint32(pkt
, ssh
->term_height
);
4711 ssh_pkt_adduint32(pkt
, ssh
->term_width
);
4712 ssh_pkt_adduint32(pkt
, 0); /* width in pixels */
4713 ssh_pkt_adduint32(pkt
, 0); /* height in pixels */
4714 parse_ttymodes(ssh
, ssh
->cfg
.ttymodes
,
4715 ssh1_send_ttymode
, (void *)pkt
);
4716 ssh_pkt_addbyte(pkt
, SSH1_TTY_OP_ISPEED
);
4717 ssh_pkt_adduint32(pkt
, ssh
->ispeed
);
4718 ssh_pkt_addbyte(pkt
, SSH1_TTY_OP_OSPEED
);
4719 ssh_pkt_adduint32(pkt
, ssh
->ospeed
);
4720 ssh_pkt_addbyte(pkt
, SSH_TTY_OP_END
);
4722 ssh
->state
= SSH_STATE_INTERMED
;
4726 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4727 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4728 bombout(("Protocol confusion"));
4730 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4731 c_write_str(ssh
, "Server refused to allocate pty\r\n");
4732 ssh
->editing
= ssh
->echoing
= 1;
4734 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
4735 ssh
->ospeed
, ssh
->ispeed
);
4737 ssh
->editing
= ssh
->echoing
= 1;
4740 if (ssh
->cfg
.compression
) {
4741 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
4745 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4746 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4747 bombout(("Protocol confusion"));
4749 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4750 c_write_str(ssh
, "Server refused to compress\r\n");
4752 logevent("Started compression");
4753 ssh
->v1_compressing
= TRUE
;
4754 ssh
->cs_comp_ctx
= zlib_compress_init();
4755 logevent("Initialised zlib (RFC1950) compression");
4756 ssh
->sc_comp_ctx
= zlib_decompress_init();
4757 logevent("Initialised zlib (RFC1950) decompression");
4761 * Start the shell or command.
4763 * Special case: if the first-choice command is an SSH-2
4764 * subsystem (hence not usable here) and the second choice
4765 * exists, we fall straight back to that.
4768 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
4770 if (!cmd
) cmd
= ssh
->cfg
.remote_cmd
;
4772 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
4773 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
4774 ssh
->fallback_cmd
= TRUE
;
4777 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
4779 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
4780 logevent("Started session");
4783 ssh
->state
= SSH_STATE_SESSION
;
4784 if (ssh
->size_needed
)
4785 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
4786 if (ssh
->eof_needed
)
4787 ssh_special(ssh
, TS_EOF
);
4790 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
4792 ssh
->channels
= newtree234(ssh_channelcmp
);
4796 * By this point, most incoming packets are already being
4797 * handled by the dispatch table, and we need only pay
4798 * attention to the unusual ones.
4803 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
4804 /* may be from EXEC_SHELL on some servers */
4805 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4806 /* may be from EXEC_SHELL on some servers
4807 * if no pty is available or in other odd cases. Ignore */
4809 bombout(("Strange packet received: type %d", pktin
->type
));
4814 int len
= min(inlen
, 512);
4815 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4816 PKT_INT
, len
, PKT_DATA
, in
, len
,
4817 PKTT_OTHER
, PKT_END
);
4828 * Handle the top-level SSH-2 protocol.
4830 static void ssh1_msg_debug(Ssh ssh
, struct Packet
*pktin
)
4835 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4836 logeventf(ssh
, "Remote debug message: %.*s", msglen
, msg
);
4839 static void ssh1_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
4841 /* log reason code in disconnect message */
4845 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4846 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen
, msg
));
4849 static void ssh_msg_ignore(Ssh ssh
, struct Packet
*pktin
)
4851 /* Do nothing, because we're ignoring it! Duhh. */
4854 static void ssh1_protocol_setup(Ssh ssh
)
4859 * Most messages are handled by the coroutines.
4861 for (i
= 0; i
< 256; i
++)
4862 ssh
->packet_dispatch
[i
] = NULL
;
4865 * These special message types we install handlers for.
4867 ssh
->packet_dispatch
[SSH1_MSG_DISCONNECT
] = ssh1_msg_disconnect
;
4868 ssh
->packet_dispatch
[SSH1_MSG_IGNORE
] = ssh_msg_ignore
;
4869 ssh
->packet_dispatch
[SSH1_MSG_DEBUG
] = ssh1_msg_debug
;
4872 static void ssh1_protocol(Ssh ssh
, void *vin
, int inlen
,
4873 struct Packet
*pktin
)
4875 unsigned char *in
=(unsigned char*)vin
;
4876 if (ssh
->state
== SSH_STATE_CLOSED
)
4879 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
4880 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
4884 if (!ssh
->protocol_initial_phase_done
) {
4885 if (do_ssh1_login(ssh
, in
, inlen
, pktin
))
4886 ssh
->protocol_initial_phase_done
= TRUE
;
4891 do_ssh1_connection(ssh
, in
, inlen
, pktin
);
4895 * Utility routine for decoding comma-separated strings in KEXINIT.
4897 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
4900 if (!needle
|| !haystack
) /* protect against null pointers */
4902 needlen
= strlen(needle
);
4905 * Is it at the start of the string?
4907 if (haylen
>= needlen
&& /* haystack is long enough */
4908 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4909 (haylen
== needlen
|| haystack
[needlen
] == ',')
4910 /* either , or EOS follows */
4914 * If not, search for the next comma and resume after that.
4915 * If no comma found, terminate.
4917 while (haylen
> 0 && *haystack
!= ',')
4918 haylen
--, haystack
++;
4921 haylen
--, haystack
++; /* skip over comma itself */
4926 * Similar routine for checking whether we have the first string in a list.
4928 static int first_in_commasep_string(char *needle
, char *haystack
, int haylen
)
4931 if (!needle
|| !haystack
) /* protect against null pointers */
4933 needlen
= strlen(needle
);
4935 * Is it at the start of the string?
4937 if (haylen
>= needlen
&& /* haystack is long enough */
4938 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4939 (haylen
== needlen
|| haystack
[needlen
] == ',')
4940 /* either , or EOS follows */
4948 * SSH-2 key creation method.
4950 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
4951 unsigned char *sessid
, char chr
,
4952 unsigned char *keyspace
)
4955 /* First 20 bytes. */
4957 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4959 SHA_Bytes(&s
, H
, 20);
4960 SHA_Bytes(&s
, &chr
, 1);
4961 SHA_Bytes(&s
, sessid
, 20);
4962 SHA_Final(&s
, keyspace
);
4963 /* Next 20 bytes. */
4965 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4967 SHA_Bytes(&s
, H
, 20);
4968 SHA_Bytes(&s
, keyspace
, 20);
4969 SHA_Final(&s
, keyspace
+ 20);
4973 * Handle the SSH-2 transport layer.
4975 static int do_ssh2_transport(Ssh ssh
, void *vin
, int inlen
,
4976 struct Packet
*pktin
)
4978 unsigned char *in
= (unsigned char *)vin
;
4979 struct do_ssh2_transport_state
{
4980 int nbits
, pbits
, warn_kex
, warn_cscipher
, warn_sccipher
;
4981 Bignum p
, g
, e
, f
, K
;
4984 int kex_init_value
, kex_reply_value
;
4985 const struct ssh_mac
**maclist
;
4987 const struct ssh2_cipher
*cscipher_tobe
;
4988 const struct ssh2_cipher
*sccipher_tobe
;
4989 const struct ssh_mac
*csmac_tobe
;
4990 const struct ssh_mac
*scmac_tobe
;
4991 const struct ssh_compress
*cscomp_tobe
;
4992 const struct ssh_compress
*sccomp_tobe
;
4993 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4994 int hostkeylen
, siglen
;
4995 void *hkey
; /* actual host key */
4996 unsigned char exchange_hash
[20];
4997 int n_preferred_kex
;
4998 const struct ssh_kex
*preferred_kex
[KEX_MAX
];
4999 int n_preferred_ciphers
;
5000 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
5001 const struct ssh_compress
*preferred_comp
;
5002 int got_session_id
, activated_authconn
;
5003 struct Packet
*pktout
;
5008 crState(do_ssh2_transport_state
);
5010 crBegin(ssh
->do_ssh2_transport_crstate
);
5012 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
5013 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
5014 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
5016 s
->got_session_id
= s
->activated_authconn
= FALSE
;
5019 * Be prepared to work around the buggy MAC problem.
5021 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
5022 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
5024 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
5027 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_KEX_MASK
;
5029 int i
, j
, commalist_started
;
5032 * Set up the preferred key exchange. (NULL => warn below here)
5034 s
->n_preferred_kex
= 0;
5035 for (i
= 0; i
< KEX_MAX
; i
++) {
5036 switch (ssh
->cfg
.ssh_kexlist
[i
]) {
5038 s
->preferred_kex
[s
->n_preferred_kex
++] =
5039 &ssh_diffiehellman_gex
;
5042 s
->preferred_kex
[s
->n_preferred_kex
++] =
5043 &ssh_diffiehellman_group14
;
5046 s
->preferred_kex
[s
->n_preferred_kex
++] =
5047 &ssh_diffiehellman_group1
;
5050 /* Flag for later. Don't bother if it's the last in
5052 if (i
< KEX_MAX
- 1) {
5053 s
->preferred_kex
[s
->n_preferred_kex
++] = NULL
;
5060 * Set up the preferred ciphers. (NULL => warn below here)
5062 s
->n_preferred_ciphers
= 0;
5063 for (i
= 0; i
< CIPHER_MAX
; i
++) {
5064 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
5065 case CIPHER_BLOWFISH
:
5066 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
5069 if (ssh
->cfg
.ssh2_des_cbc
) {
5070 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
5074 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
5077 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
5079 case CIPHER_ARCFOUR
:
5080 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_arcfour
;
5083 /* Flag for later. Don't bother if it's the last in
5085 if (i
< CIPHER_MAX
- 1) {
5086 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
5093 * Set up preferred compression.
5095 if (ssh
->cfg
.compression
)
5096 s
->preferred_comp
= &ssh_zlib
;
5098 s
->preferred_comp
= &ssh_comp_none
;
5101 * Enable queueing of outgoing auth- or connection-layer
5102 * packets while we are in the middle of a key exchange.
5104 ssh
->queueing
= TRUE
;
5107 * Flag that KEX is in progress.
5109 ssh
->kex_in_progress
= TRUE
;
5112 * Construct and send our key exchange packet.
5114 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEXINIT
);
5115 for (i
= 0; i
< 16; i
++)
5116 ssh2_pkt_addbyte(s
->pktout
, (unsigned char) random_byte());
5117 /* List key exchange algorithms. */
5118 ssh2_pkt_addstring_start(s
->pktout
);
5119 commalist_started
= 0;
5120 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
5121 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
5122 if (!k
) continue; /* warning flag */
5123 if (commalist_started
)
5124 ssh2_pkt_addstring_str(s
->pktout
, ",");
5125 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_kex
[i
]->name
);
5126 commalist_started
= 1;
5128 /* List server host key algorithms. */
5129 ssh2_pkt_addstring_start(s
->pktout
);
5130 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
5131 ssh2_pkt_addstring_str(s
->pktout
, hostkey_algs
[i
]->name
);
5132 if (i
< lenof(hostkey_algs
) - 1)
5133 ssh2_pkt_addstring_str(s
->pktout
, ",");
5135 /* List client->server encryption algorithms. */
5136 ssh2_pkt_addstring_start(s
->pktout
);
5137 commalist_started
= 0;
5138 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5139 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5140 if (!c
) continue; /* warning flag */
5141 for (j
= 0; j
< c
->nciphers
; j
++) {
5142 if (commalist_started
)
5143 ssh2_pkt_addstring_str(s
->pktout
, ",");
5144 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
5145 commalist_started
= 1;
5148 /* List server->client encryption algorithms. */
5149 ssh2_pkt_addstring_start(s
->pktout
);
5150 commalist_started
= 0;
5151 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5152 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5153 if (!c
) continue; /* warning flag */
5154 for (j
= 0; j
< c
->nciphers
; j
++) {
5155 if (commalist_started
)
5156 ssh2_pkt_addstring_str(s
->pktout
, ",");
5157 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
5158 commalist_started
= 1;
5161 /* List client->server MAC algorithms. */
5162 ssh2_pkt_addstring_start(s
->pktout
);
5163 for (i
= 0; i
< s
->nmacs
; i
++) {
5164 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
5165 if (i
< s
->nmacs
- 1)
5166 ssh2_pkt_addstring_str(s
->pktout
, ",");
5168 /* List server->client MAC algorithms. */
5169 ssh2_pkt_addstring_start(s
->pktout
);
5170 for (i
= 0; i
< s
->nmacs
; i
++) {
5171 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
5172 if (i
< s
->nmacs
- 1)
5173 ssh2_pkt_addstring_str(s
->pktout
, ",");
5175 /* List client->server compression algorithms. */
5176 ssh2_pkt_addstring_start(s
->pktout
);
5177 assert(lenof(compressions
) > 1);
5178 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
5179 for (i
= 0; i
< lenof(compressions
); i
++) {
5180 const struct ssh_compress
*c
= compressions
[i
];
5181 if (c
!= s
->preferred_comp
) {
5182 ssh2_pkt_addstring_str(s
->pktout
, ",");
5183 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
5186 /* List server->client compression algorithms. */
5187 ssh2_pkt_addstring_start(s
->pktout
);
5188 assert(lenof(compressions
) > 1);
5189 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
5190 for (i
= 0; i
< lenof(compressions
); i
++) {
5191 const struct ssh_compress
*c
= compressions
[i
];
5192 if (c
!= s
->preferred_comp
) {
5193 ssh2_pkt_addstring_str(s
->pktout
, ",");
5194 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
5197 /* List client->server languages. Empty list. */
5198 ssh2_pkt_addstring_start(s
->pktout
);
5199 /* List server->client languages. Empty list. */
5200 ssh2_pkt_addstring_start(s
->pktout
);
5201 /* First KEX packet does _not_ follow, because we're not that brave. */
5202 ssh2_pkt_addbool(s
->pktout
, FALSE
);
5204 ssh2_pkt_adduint32(s
->pktout
, 0);
5207 s
->our_kexinitlen
= s
->pktout
->length
- 5;
5208 s
->our_kexinit
= snewn(s
->our_kexinitlen
, unsigned char);
5209 memcpy(s
->our_kexinit
, s
->pktout
->data
+ 5, s
->our_kexinitlen
);
5211 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5217 * Now examine the other side's KEXINIT to see what we're up
5221 char *str
, *preferred
;
5224 if (pktin
->type
!= SSH2_MSG_KEXINIT
) {
5225 bombout(("expected key exchange packet from server"));
5229 ssh
->hostkey
= NULL
;
5230 s
->cscipher_tobe
= NULL
;
5231 s
->sccipher_tobe
= NULL
;
5232 s
->csmac_tobe
= NULL
;
5233 s
->scmac_tobe
= NULL
;
5234 s
->cscomp_tobe
= NULL
;
5235 s
->sccomp_tobe
= NULL
;
5236 s
->warn_kex
= s
->warn_cscipher
= s
->warn_sccipher
= FALSE
;
5238 pktin
->savedpos
+= 16; /* skip garbage cookie */
5239 ssh_pkt_getstring(pktin
, &str
, &len
); /* key exchange algorithms */
5242 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
5243 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
5247 if (!preferred
) preferred
= k
->name
;
5248 if (in_commasep_string(k
->name
, str
, len
))
5255 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
5256 str ? str
: "(null)"));
5260 * Note that the server's guess is considered wrong if it doesn't match
5261 * the first algorithm in our list, even if it's still the algorithm
5264 s
->guessok
= first_in_commasep_string(preferred
, str
, len
);
5265 ssh_pkt_getstring(pktin
, &str
, &len
); /* host key algorithms */
5266 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
5267 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
5268 ssh
->hostkey
= hostkey_algs
[i
];
5272 s
->guessok
= s
->guessok
&&
5273 first_in_commasep_string(hostkey_algs
[0]->name
, str
, len
);
5274 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server cipher */
5275 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5276 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5278 s
->warn_cscipher
= TRUE
;
5280 for (j
= 0; j
< c
->nciphers
; j
++) {
5281 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
5282 s
->cscipher_tobe
= c
->list
[j
];
5287 if (s
->cscipher_tobe
)
5290 if (!s
->cscipher_tobe
) {
5291 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
5292 str ? str
: "(null)"));
5296 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client cipher */
5297 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5298 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5300 s
->warn_sccipher
= TRUE
;
5302 for (j
= 0; j
< c
->nciphers
; j
++) {
5303 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
5304 s
->sccipher_tobe
= c
->list
[j
];
5309 if (s
->sccipher_tobe
)
5312 if (!s
->sccipher_tobe
) {
5313 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
5314 str ? str
: "(null)"));
5318 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server mac */
5319 for (i
= 0; i
< s
->nmacs
; i
++) {
5320 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5321 s
->csmac_tobe
= s
->maclist
[i
];
5325 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client mac */
5326 for (i
= 0; i
< s
->nmacs
; i
++) {
5327 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5328 s
->scmac_tobe
= s
->maclist
[i
];
5332 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server compression */
5333 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5334 const struct ssh_compress
*c
=
5335 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5336 if (in_commasep_string(c
->name
, str
, len
)) {
5341 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client compression */
5342 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5343 const struct ssh_compress
*c
=
5344 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5345 if (in_commasep_string(c
->name
, str
, len
)) {
5350 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server language */
5351 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client language */
5352 s
->ignorepkt
= ssh2_pkt_getbool(pktin
) && !s
->guessok
;
5355 ssh_set_frozen(ssh
, 1);
5356 s
->dlgret
= askalg(ssh
->frontend
, "key-exchange algorithm",
5358 ssh_dialog_callback
, ssh
);
5359 if (s
->dlgret
< 0) {
5363 bombout(("Unexpected data from server while"
5364 " waiting for user response"));
5367 } while (pktin
|| inlen
> 0);
5368 s
->dlgret
= ssh
->user_response
;
5370 ssh_set_frozen(ssh
, 0);
5371 if (s
->dlgret
== 0) {
5372 ssh_disconnect(ssh
, "User aborted at kex warning", NULL
,
5378 if (s
->warn_cscipher
) {
5379 ssh_set_frozen(ssh
, 1);
5380 s
->dlgret
= askalg(ssh
->frontend
,
5381 "client-to-server cipher",
5382 s
->cscipher_tobe
->name
,
5383 ssh_dialog_callback
, ssh
);
5384 if (s
->dlgret
< 0) {
5388 bombout(("Unexpected data from server while"
5389 " waiting for user response"));
5392 } while (pktin
|| inlen
> 0);
5393 s
->dlgret
= ssh
->user_response
;
5395 ssh_set_frozen(ssh
, 0);
5396 if (s
->dlgret
== 0) {
5397 ssh_disconnect(ssh
, "User aborted at cipher warning", NULL
,
5403 if (s
->warn_sccipher
) {
5404 ssh_set_frozen(ssh
, 1);
5405 s
->dlgret
= askalg(ssh
->frontend
,
5406 "server-to-client cipher",
5407 s
->sccipher_tobe
->name
,
5408 ssh_dialog_callback
, ssh
);
5409 if (s
->dlgret
< 0) {
5413 bombout(("Unexpected data from server while"
5414 " waiting for user response"));
5417 } while (pktin
|| inlen
> 0);
5418 s
->dlgret
= ssh
->user_response
;
5420 ssh_set_frozen(ssh
, 0);
5421 if (s
->dlgret
== 0) {
5422 ssh_disconnect(ssh
, "User aborted at cipher warning", NULL
,
5428 SHA_Init(&ssh
->exhash
);
5429 sha_string(&ssh
->exhash
, ssh
->v_c
, strlen(ssh
->v_c
));
5430 sha_string(&ssh
->exhash
, ssh
->v_s
, strlen(ssh
->v_s
));
5431 sha_string(&ssh
->exhash
, s
->our_kexinit
, s
->our_kexinitlen
);
5432 sfree(s
->our_kexinit
);
5433 if (pktin
->length
> 5)
5434 sha_string(&ssh
->exhash
, pktin
->data
+ 5, pktin
->length
- 5);
5437 if (s
->ignorepkt
) /* first_kex_packet_follows */
5438 crWaitUntil(pktin
); /* Ignore packet */
5442 * Work out the number of bits of key we will need from the key
5443 * exchange. We start with the maximum key length of either
5449 csbits
= s
->cscipher_tobe
->keylen
;
5450 scbits
= s
->sccipher_tobe
->keylen
;
5451 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
5453 /* The keys only have 160-bit entropy, since they're based on
5454 * a SHA-1 hash. So cap the key size at 160 bits. */
5459 * If we're doing Diffie-Hellman group exchange, start by
5460 * requesting a group.
5462 if (!ssh
->kex
->pdata
) {
5463 logevent("Doing Diffie-Hellman group exchange");
5464 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
5466 * Work out how big a DH group we will need to allow that
5469 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
5470 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
5471 ssh2_pkt_adduint32(s
->pktout
, s
->pbits
);
5472 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5475 if (pktin
->type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
5476 bombout(("expected key exchange group packet from server"));
5479 s
->p
= ssh2_pkt_getmp(pktin
);
5480 s
->g
= ssh2_pkt_getmp(pktin
);
5481 if (!s
->p
|| !s
->g
) {
5482 bombout(("unable to read mp-ints from incoming group packet"));
5485 ssh
->kex_ctx
= dh_setup_gex(s
->p
, s
->g
);
5486 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
5487 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
5489 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP
;
5490 ssh
->kex_ctx
= dh_setup_group(ssh
->kex
);
5491 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
5492 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
5493 logeventf(ssh
, "Using Diffie-Hellman with standard group \"%s\"",
5494 ssh
->kex
->groupname
);
5497 logevent("Doing Diffie-Hellman key exchange");
5499 * Now generate and send e for Diffie-Hellman.
5501 set_busy_status(ssh
->frontend
, BUSY_CPU
); /* this can take a while */
5502 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
5503 s
->pktout
= ssh2_pkt_init(s
->kex_init_value
);
5504 ssh2_pkt_addmp(s
->pktout
, s
->e
);
5505 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5507 set_busy_status(ssh
->frontend
, BUSY_WAITING
); /* wait for server */
5509 if (pktin
->type
!= s
->kex_reply_value
) {
5510 bombout(("expected key exchange reply packet from server"));
5513 set_busy_status(ssh
->frontend
, BUSY_CPU
); /* cogitate */
5514 ssh_pkt_getstring(pktin
, &s
->hostkeydata
, &s
->hostkeylen
);
5515 s
->f
= ssh2_pkt_getmp(pktin
);
5517 bombout(("unable to parse key exchange reply packet"));
5520 ssh_pkt_getstring(pktin
, &s
->sigdata
, &s
->siglen
);
5522 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
5524 /* We assume everything from now on will be quick, and it might
5525 * involve user interaction. */
5526 set_busy_status(ssh
->frontend
, BUSY_NOT
);
5528 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
5529 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5530 sha_uint32(&ssh
->exhash
, s
->pbits
);
5531 sha_mpint(&ssh
->exhash
, s
->p
);
5532 sha_mpint(&ssh
->exhash
, s
->g
);
5534 sha_mpint(&ssh
->exhash
, s
->e
);
5535 sha_mpint(&ssh
->exhash
, s
->f
);
5536 sha_mpint(&ssh
->exhash
, s
->K
);
5537 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
5539 dh_cleanup(ssh
->kex_ctx
);
5540 ssh
->kex_ctx
= NULL
;
5543 debug(("Exchange hash is:\n"));
5544 dmemdump(s
->exchange_hash
, 20);
5547 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
5549 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
5550 (char *)s
->exchange_hash
, 20)) {
5551 bombout(("Server's host key did not match the signature supplied"));
5556 * Authenticate remote host: verify host key. (We've already
5557 * checked the signature of the exchange hash.)
5559 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
5560 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
5561 ssh_set_frozen(ssh
, 1);
5562 s
->dlgret
= verify_ssh_host_key(ssh
->frontend
,
5563 ssh
->savedhost
, ssh
->savedport
,
5564 ssh
->hostkey
->keytype
, s
->keystr
,
5566 ssh_dialog_callback
, ssh
);
5567 if (s
->dlgret
< 0) {
5571 bombout(("Unexpected data from server while waiting"
5572 " for user host key response"));
5575 } while (pktin
|| inlen
> 0);
5576 s
->dlgret
= ssh
->user_response
;
5578 ssh_set_frozen(ssh
, 0);
5579 if (s
->dlgret
== 0) {
5580 ssh_disconnect(ssh
, "User aborted at host key verification", NULL
,
5584 if (!s
->got_session_id
) { /* don't bother logging this in rekeys */
5585 logevent("Host key fingerprint is:");
5586 logevent(s
->fingerprint
);
5588 sfree(s
->fingerprint
);
5590 ssh
->hostkey
->freekey(s
->hkey
);
5593 * The exchange hash from the very first key exchange is also
5594 * the session id, used in session key construction and
5597 if (!s
->got_session_id
) {
5598 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
5599 sizeof(s
->exchange_hash
));
5600 s
->got_session_id
= TRUE
;
5604 * Send SSH2_MSG_NEWKEYS.
5606 s
->pktout
= ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
5607 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5608 ssh
->outgoing_data_size
= 0; /* start counting from here */
5611 * We've sent client NEWKEYS, so create and initialise
5612 * client-to-server session keys.
5614 if (ssh
->cs_cipher_ctx
)
5615 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
5616 ssh
->cscipher
= s
->cscipher_tobe
;
5617 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
5619 if (ssh
->cs_mac_ctx
)
5620 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
5621 ssh
->csmac
= s
->csmac_tobe
;
5622 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
5624 if (ssh
->cs_comp_ctx
)
5625 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
5626 ssh
->cscomp
= s
->cscomp_tobe
;
5627 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
5630 * Set IVs on client-to-server keys. Here we use the exchange
5631 * hash from the _first_ key exchange.
5634 unsigned char keyspace
[40];
5635 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
5636 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
5637 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
5638 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
5639 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
5640 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
5643 logeventf(ssh
, "Initialised %.200s client->server encryption",
5644 ssh
->cscipher
->text_name
);
5645 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
5646 ssh
->csmac
->text_name
);
5647 if (ssh
->cscomp
->text_name
)
5648 logeventf(ssh
, "Initialised %s compression",
5649 ssh
->cscomp
->text_name
);
5652 * Now our end of the key exchange is complete, we can send all
5653 * our queued higher-layer packets.
5655 ssh
->queueing
= FALSE
;
5656 ssh2_pkt_queuesend(ssh
);
5659 * Expect SSH2_MSG_NEWKEYS from server.
5662 if (pktin
->type
!= SSH2_MSG_NEWKEYS
) {
5663 bombout(("expected new-keys packet from server"));
5666 ssh
->incoming_data_size
= 0; /* start counting from here */
5669 * We've seen server NEWKEYS, so create and initialise
5670 * server-to-client session keys.
5672 if (ssh
->sc_cipher_ctx
)
5673 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
5674 ssh
->sccipher
= s
->sccipher_tobe
;
5675 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
5677 if (ssh
->sc_mac_ctx
)
5678 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
5679 ssh
->scmac
= s
->scmac_tobe
;
5680 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
5682 if (ssh
->sc_comp_ctx
)
5683 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
5684 ssh
->sccomp
= s
->sccomp_tobe
;
5685 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
5688 * Set IVs on server-to-client keys. Here we use the exchange
5689 * hash from the _first_ key exchange.
5692 unsigned char keyspace
[40];
5693 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
5694 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
5695 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
5696 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
5697 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
5698 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
5700 logeventf(ssh
, "Initialised %.200s server->client encryption",
5701 ssh
->sccipher
->text_name
);
5702 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
5703 ssh
->scmac
->text_name
);
5704 if (ssh
->sccomp
->text_name
)
5705 logeventf(ssh
, "Initialised %s decompression",
5706 ssh
->sccomp
->text_name
);
5709 * Free key exchange data.
5713 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5719 * Key exchange is over. Loop straight back round if we have a
5720 * deferred rekey reason.
5722 if (ssh
->deferred_rekey_reason
) {
5723 logevent(ssh
->deferred_rekey_reason
);
5725 ssh
->deferred_rekey_reason
= NULL
;
5726 goto begin_key_exchange
;
5730 * Otherwise, schedule a timer for our next rekey.
5732 ssh
->kex_in_progress
= FALSE
;
5733 ssh
->last_rekey
= GETTICKCOUNT();
5734 if (ssh
->cfg
.ssh_rekey_time
!= 0)
5735 ssh
->next_rekey
= schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5739 * If this is the first key exchange phase, we must pass the
5740 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5741 * wants to see it but because it will need time to initialise
5742 * itself before it sees an actual packet. In subsequent key
5743 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5744 * it would only confuse the layer above.
5746 if (s
->activated_authconn
) {
5749 s
->activated_authconn
= TRUE
;
5752 * Now we're encrypting. Begin returning 1 to the protocol main
5753 * function so that other things can run on top of the
5754 * transport. If we ever see a KEXINIT, we must go back to the
5757 * We _also_ go back to the start if we see pktin==NULL and
5758 * inlen==-1, because this is a special signal meaning
5759 * `initiate client-driven rekey', and `in' contains a message
5760 * giving the reason for the rekey.
5762 while (!((pktin
&& pktin
->type
== SSH2_MSG_KEXINIT
) ||
5763 (!pktin
&& inlen
== -1))) {
5768 logevent("Server initiated key re-exchange");
5771 * Special case: if the server bug is set that doesn't
5772 * allow rekeying, we give a different log message and
5773 * continue waiting. (If such a server _initiates_ a rekey,
5774 * we process it anyway!)
5776 if ((ssh
->remote_bugs
& BUG_SSH2_REKEY
)) {
5777 logeventf(ssh
, "Server bug prevents key re-exchange (%s)",
5779 /* Reset the counters, so that at least this message doesn't
5780 * hit the event log _too_ often. */
5781 ssh
->outgoing_data_size
= 0;
5782 ssh
->incoming_data_size
= 0;
5783 if (ssh
->cfg
.ssh_rekey_time
!= 0) {
5785 schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5788 goto wait_for_rekey
; /* this is utterly horrid */
5790 logeventf(ssh
, "Initiating key re-exchange (%s)", (char *)in
);
5793 goto begin_key_exchange
;
5799 * Add data to an SSH-2 channel output buffer.
5801 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
5804 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
5808 * Attempt to send data on an SSH-2 channel.
5810 static int ssh2_try_send(struct ssh_channel
*c
)
5813 struct Packet
*pktout
;
5815 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
5818 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
5819 if ((unsigned)len
> c
->v
.v2
.remwindow
)
5820 len
= c
->v
.v2
.remwindow
;
5821 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
5822 len
= c
->v
.v2
.remmaxpkt
;
5823 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
5824 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5825 dont_log_data(ssh
, pktout
, PKTLOG_OMIT
);
5826 ssh2_pkt_addstring_start(pktout
);
5827 ssh2_pkt_addstring_data(pktout
, data
, len
);
5828 end_log_omission(ssh
, pktout
);
5829 ssh2_pkt_send(ssh
, pktout
);
5830 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
5831 c
->v
.v2
.remwindow
-= len
;
5835 * After having sent as much data as we can, return the amount
5838 return bufchain_size(&c
->v
.v2
.outbuffer
);
5841 static void ssh2_try_send_and_unthrottle(struct ssh_channel
*c
)
5845 return; /* don't send on closing channels */
5846 bufsize
= ssh2_try_send(c
);
5849 case CHAN_MAINSESSION
:
5850 /* stdin need not receive an unthrottle
5851 * notification since it will be polled */
5854 x11_unthrottle(c
->u
.x11
.s
);
5857 /* agent sockets are request/response and need no
5858 * buffer management */
5861 pfd_unthrottle(c
->u
.pfd
.s
);
5868 * Potentially enlarge the window on an SSH-2 channel.
5870 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
5875 * Never send WINDOW_ADJUST for a channel that the remote side
5876 * already thinks it's closed; there's no point, since it won't
5877 * be sending any more data anyway.
5883 * Only send a WINDOW_ADJUST if there's significantly more window
5884 * available than the other end thinks there is. This saves us
5885 * sending a WINDOW_ADJUST for every character in a shell session.
5887 * "Significant" is arbitrarily defined as half the window size.
5889 if (newwin
> c
->v
.v2
.locwindow
* 2) {
5890 struct Packet
*pktout
;
5892 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5893 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5894 ssh2_pkt_adduint32(pktout
, newwin
- c
->v
.v2
.locwindow
);
5895 ssh2_pkt_send(ssh
, pktout
);
5896 c
->v
.v2
.locwindow
= newwin
;
5900 static void ssh2_msg_channel_window_adjust(Ssh ssh
, struct Packet
*pktin
)
5902 unsigned i
= ssh_pkt_getuint32(pktin
);
5903 struct ssh_channel
*c
;
5904 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5905 if (c
&& !c
->closes
) {
5906 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
5907 ssh2_try_send_and_unthrottle(c
);
5911 static void ssh2_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
5915 unsigned i
= ssh_pkt_getuint32(pktin
);
5916 struct ssh_channel
*c
;
5917 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5919 return; /* nonexistent channel */
5920 if (pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5921 ssh_pkt_getuint32(pktin
) != SSH2_EXTENDED_DATA_STDERR
)
5922 return; /* extended but not stderr */
5923 ssh_pkt_getstring(pktin
, &data
, &length
);
5926 c
->v
.v2
.locwindow
-= length
;
5928 case CHAN_MAINSESSION
:
5930 from_backend(ssh
->frontend
, pktin
->type
==
5931 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5935 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5938 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5941 while (length
> 0) {
5942 if (c
->u
.a
.lensofar
< 4) {
5943 unsigned int l
= min(4 - c
->u
.a
.lensofar
, length
);
5944 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5948 c
->u
.a
.lensofar
+= l
;
5950 if (c
->u
.a
.lensofar
== 4) {
5952 4 + GET_32BIT(c
->u
.a
.msglen
);
5953 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
5955 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5957 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5959 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5961 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5965 c
->u
.a
.lensofar
+= l
;
5967 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5970 if (agent_query(c
->u
.a
.message
,
5973 ssh_agentf_callback
, c
))
5974 ssh_agentf_callback(c
, reply
, replylen
);
5975 sfree(c
->u
.a
.message
);
5976 c
->u
.a
.lensofar
= 0;
5983 * If we are not buffering too much data,
5984 * enlarge the window again at the remote side.
5986 if (bufsize
< OUR_V2_WINSIZE
)
5987 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5991 static void ssh2_msg_channel_eof(Ssh ssh
, struct Packet
*pktin
)
5993 unsigned i
= ssh_pkt_getuint32(pktin
);
5994 struct ssh_channel
*c
;
5996 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5998 return; /* nonexistent channel */
6000 if (c
->type
== CHAN_X11
) {
6002 * Remote EOF on an X11 channel means we should
6003 * wrap up and close the channel ourselves.
6005 x11_close(c
->u
.x11
.s
);
6007 } else if (c
->type
== CHAN_AGENT
) {
6009 } else if (c
->type
== CHAN_SOCKDATA
) {
6010 pfd_close(c
->u
.pfd
.s
);
6015 static void ssh2_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
6017 unsigned i
= ssh_pkt_getuint32(pktin
);
6018 struct ssh_channel
*c
;
6019 struct Packet
*pktout
;
6021 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6022 if (!c
|| c
->halfopen
) {
6023 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
6024 c ?
"half-open" : "nonexistent", i
));
6027 /* Do pre-close processing on the channel. */
6029 case CHAN_MAINSESSION
:
6030 ssh
->mainchan
= NULL
;
6031 update_specials_menu(ssh
->frontend
);
6034 if (c
->u
.x11
.s
!= NULL
)
6035 x11_close(c
->u
.x11
.s
);
6042 if (c
->u
.pfd
.s
!= NULL
)
6043 pfd_close(c
->u
.pfd
.s
);
6047 if (c
->closes
== 0) {
6048 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
6049 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6050 ssh2_pkt_send(ssh
, pktout
);
6052 del234(ssh
->channels
, c
);
6053 bufchain_clear(&c
->v
.v2
.outbuffer
);
6057 * See if that was the last channel left open.
6058 * (This is only our termination condition if we're
6059 * not running in -N mode.)
6061 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
6063 * We used to send SSH_MSG_DISCONNECT here,
6064 * because I'd believed that _every_ conforming
6065 * SSH-2 connection had to end with a disconnect
6066 * being sent by at least one side; apparently
6067 * I was wrong and it's perfectly OK to
6068 * unceremoniously slam the connection shut
6069 * when you're done, and indeed OpenSSH feels
6070 * this is more polite than sending a
6071 * DISCONNECT. So now we don't.
6073 ssh_disconnect(ssh
, "All channels closed", NULL
, 0, TRUE
);
6077 static void ssh2_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
6079 unsigned i
= ssh_pkt_getuint32(pktin
);
6080 struct ssh_channel
*c
;
6081 struct Packet
*pktout
;
6083 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6085 return; /* nonexistent channel */
6086 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
6087 return; /* dunno why they're confirming this */
6088 c
->remoteid
= ssh_pkt_getuint32(pktin
);
6089 c
->halfopen
= FALSE
;
6090 c
->type
= CHAN_SOCKDATA
;
6091 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
6092 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
6094 pfd_confirm(c
->u
.pfd
.s
);
6097 * We have a pending close on this channel,
6098 * which we decided on before the server acked
6099 * the channel open. So now we know the
6100 * remoteid, we can close it again.
6102 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
6103 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6104 ssh2_pkt_send(ssh
, pktout
);
6108 static void ssh2_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
6110 static const char *const reasons
[] = {
6111 "<unknown reason code>",
6112 "Administratively prohibited",
6114 "Unknown channel type",
6115 "Resource shortage",
6117 unsigned i
= ssh_pkt_getuint32(pktin
);
6118 unsigned reason_code
;
6119 char *reason_string
;
6121 struct ssh_channel
*c
;
6122 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6124 return; /* nonexistent channel */
6125 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
6126 return; /* dunno why they're failing this */
6128 reason_code
= ssh_pkt_getuint32(pktin
);
6129 if (reason_code
>= lenof(reasons
))
6130 reason_code
= 0; /* ensure reasons[reason_code] in range */
6131 ssh_pkt_getstring(pktin
, &reason_string
, &reason_length
);
6132 logeventf(ssh
, "Forwarded connection refused by server: %s [%.*s]",
6133 reasons
[reason_code
], reason_length
, reason_string
);
6135 pfd_close(c
->u
.pfd
.s
);
6137 del234(ssh
->channels
, c
);
6141 static void ssh2_msg_channel_request(Ssh ssh
, struct Packet
*pktin
)
6145 int typelen
, want_reply
;
6146 int reply
= SSH2_MSG_CHANNEL_FAILURE
; /* default */
6147 struct ssh_channel
*c
;
6148 struct Packet
*pktout
;
6150 localid
= ssh_pkt_getuint32(pktin
);
6151 ssh_pkt_getstring(pktin
, &type
, &typelen
);
6152 want_reply
= ssh2_pkt_getbool(pktin
);
6155 * First, check that the channel exists. Otherwise,
6156 * we can instantly disconnect with a rude message.
6158 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
6160 char *buf
= dupprintf("Received channel request for nonexistent"
6161 " channel %d", localid
);
6162 ssh_disconnect(ssh
, NULL
, buf
, SSH2_DISCONNECT_PROTOCOL_ERROR
, FALSE
);
6168 * Having got the channel number, we now look at
6169 * the request type string to see if it's something
6172 if (c
== ssh
->mainchan
) {
6174 * We recognise "exit-status" and "exit-signal" on
6175 * the primary channel.
6177 if (typelen
== 11 &&
6178 !memcmp(type
, "exit-status", 11)) {
6180 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
6181 logeventf(ssh
, "Server sent command exit status %d",
6183 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
6185 } else if (typelen
== 11 &&
6186 !memcmp(type
, "exit-signal", 11)) {
6188 int is_plausible
= TRUE
, is_int
= FALSE
;
6189 char *fmt_sig
= "", *fmt_msg
= "";
6191 int msglen
= 0, core
= FALSE
;
6192 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
6193 * provide an `int' for the signal, despite its
6194 * having been a `string' in the drafts since at
6195 * least 2001. (Fixed in session.c 1.147.) Try to
6196 * infer which we can safely parse it as. */
6198 unsigned char *p
= pktin
->body
+
6200 long len
= pktin
->length
- pktin
->savedpos
;
6201 unsigned long num
= GET_32BIT(p
); /* what is it? */
6202 /* If it's 0, it hardly matters; assume string */
6206 int maybe_int
= FALSE
, maybe_str
= FALSE
;
6207 #define CHECK_HYPOTHESIS(offset, result) \
6210 if (q >= 0 && q+4 <= len) { \
6211 q = q + 4 + GET_32BIT(p+q); \
6212 if (q >= 0 && q+4 <= len && \
6213 ((q = q + 4 + GET_32BIT(p+q))!= 0) && q == len) \
6217 CHECK_HYPOTHESIS(4+1, maybe_int
);
6218 CHECK_HYPOTHESIS(4+num
+1, maybe_str
);
6219 #undef CHECK_HYPOTHESIS
6220 if (maybe_int
&& !maybe_str
)
6222 else if (!maybe_int
&& maybe_str
)
6225 /* Crikey. Either or neither. Panic. */
6226 is_plausible
= FALSE
;
6231 /* Old non-standard OpenSSH. */
6232 int signum
= ssh_pkt_getuint32(pktin
);
6233 fmt_sig
= dupprintf(" %d", signum
);
6235 /* As per the drafts. */
6238 ssh_pkt_getstring(pktin
, &sig
, &siglen
);
6239 /* Signal name isn't supposed to be blank, but
6240 * let's cope gracefully if it is. */
6242 fmt_sig
= dupprintf(" \"%.*s\"",
6246 core
= ssh2_pkt_getbool(pktin
);
6247 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
6249 fmt_msg
= dupprintf(" (\"%.*s\")", msglen
, msg
);
6251 /* ignore lang tag */
6252 } /* else don't attempt to parse */
6253 logeventf(ssh
, "Server exited on signal%s%s%s",
6254 fmt_sig
, core ?
" (core dumped)" : "",
6256 if (*fmt_sig
) sfree(fmt_sig
);
6257 if (*fmt_msg
) sfree(fmt_msg
);
6258 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
6263 * This is a channel request we don't know
6264 * about, so we now either ignore the request
6265 * or respond with CHANNEL_FAILURE, depending
6268 reply
= SSH2_MSG_CHANNEL_FAILURE
;
6271 pktout
= ssh2_pkt_init(reply
);
6272 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6273 ssh2_pkt_send(ssh
, pktout
);
6277 static void ssh2_msg_global_request(Ssh ssh
, struct Packet
*pktin
)
6280 int typelen
, want_reply
;
6281 struct Packet
*pktout
;
6283 ssh_pkt_getstring(pktin
, &type
, &typelen
);
6284 want_reply
= ssh2_pkt_getbool(pktin
);
6287 * We currently don't support any global requests
6288 * at all, so we either ignore the request or
6289 * respond with REQUEST_FAILURE, depending on
6293 pktout
= ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
6294 ssh2_pkt_send(ssh
, pktout
);
6298 static void ssh2_msg_channel_open(Ssh ssh
, struct Packet
*pktin
)
6306 struct ssh_channel
*c
;
6307 unsigned remid
, winsize
, pktsize
;
6308 struct Packet
*pktout
;
6310 ssh_pkt_getstring(pktin
, &type
, &typelen
);
6311 c
= snew(struct ssh_channel
);
6314 remid
= ssh_pkt_getuint32(pktin
);
6315 winsize
= ssh_pkt_getuint32(pktin
);
6316 pktsize
= ssh_pkt_getuint32(pktin
);
6318 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
6321 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
6322 addrstr
= snewn(peeraddrlen
+1, char);
6323 memcpy(addrstr
, peeraddr
, peeraddrlen
);
6324 addrstr
[peeraddrlen
] = '\0';
6325 peerport
= ssh_pkt_getuint32(pktin
);
6327 logeventf(ssh
, "Received X11 connect request from %s:%d",
6330 if (!ssh
->X11_fwd_enabled
)
6331 error
= "X11 forwarding is not enabled";
6332 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
6333 ssh
->x11auth
, addrstr
, peerport
,
6334 &ssh
->cfg
) != NULL
) {
6335 error
= "Unable to open an X11 connection";
6337 logevent("Opening X11 forward connection succeeded");
6342 } else if (typelen
== 15 &&
6343 !memcmp(type
, "forwarded-tcpip", 15)) {
6344 struct ssh_rportfwd pf
, *realpf
;
6347 ssh_pkt_getstring(pktin
, &dummy
, &dummylen
);/* skip address */
6348 pf
.sport
= ssh_pkt_getuint32(pktin
);
6349 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
6350 peerport
= ssh_pkt_getuint32(pktin
);
6351 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
6352 logeventf(ssh
, "Received remote port %d open request "
6353 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
6354 if (realpf
== NULL
) {
6355 error
= "Remote port is not recognised";
6357 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
6361 realpf
->pfrec
->addressfamily
);
6362 logeventf(ssh
, "Attempting to forward remote port to "
6363 "%s:%d", realpf
->dhost
, realpf
->dport
);
6365 logeventf(ssh
, "Port open failed: %s", e
);
6366 error
= "Port open failed";
6368 logevent("Forwarded port opened successfully");
6369 c
->type
= CHAN_SOCKDATA
;
6372 } else if (typelen
== 22 &&
6373 !memcmp(type
, "auth-agent@openssh.com", 22)) {
6374 if (!ssh
->agentfwd_enabled
)
6375 error
= "Agent forwarding is not enabled";
6377 c
->type
= CHAN_AGENT
; /* identify channel type */
6378 c
->u
.a
.lensofar
= 0;
6381 error
= "Unsupported channel type requested";
6384 c
->remoteid
= remid
;
6385 c
->halfopen
= FALSE
;
6387 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
6388 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6389 ssh2_pkt_adduint32(pktout
, SSH2_OPEN_CONNECT_FAILED
);
6390 ssh2_pkt_addstring(pktout
, error
);
6391 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
6392 ssh2_pkt_send(ssh
, pktout
);
6393 logeventf(ssh
, "Rejected channel open: %s", error
);
6396 c
->localid
= alloc_channel_id(ssh
);
6398 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6399 c
->v
.v2
.remwindow
= winsize
;
6400 c
->v
.v2
.remmaxpkt
= pktsize
;
6401 bufchain_init(&c
->v
.v2
.outbuffer
);
6402 add234(ssh
->channels
, c
);
6403 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
6404 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6405 ssh2_pkt_adduint32(pktout
, c
->localid
);
6406 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);
6407 ssh2_pkt_adduint32(pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
6408 ssh2_pkt_send(ssh
, pktout
);
6413 * Buffer banner messages for later display at some convenient point.
6415 static void ssh2_msg_userauth_banner(Ssh ssh
, struct Packet
*pktin
)
6417 /* Arbitrary limit to prevent unbounded inflation of buffer */
6418 if (bufchain_size(&ssh
->banner
) <= 131072) {
6419 char *banner
= NULL
;
6421 ssh_pkt_getstring(pktin
, &banner
, &size
);
6423 bufchain_add(&ssh
->banner
, banner
, size
);
6427 /* Helper function to deal with sending tty modes for "pty-req" */
6428 static void ssh2_send_ttymode(void *data
, char *mode
, char *val
)
6430 struct Packet
*pktout
= (struct Packet
*)data
;
6432 unsigned int arg
= 0;
6433 while (strcmp(mode
, ssh_ttymodes
[i
].mode
) != 0) i
++;
6434 if (i
== lenof(ssh_ttymodes
)) return;
6435 switch (ssh_ttymodes
[i
].type
) {
6437 arg
= ssh_tty_parse_specchar(val
);
6440 arg
= ssh_tty_parse_boolean(val
);
6443 ssh2_pkt_addbyte(pktout
, ssh_ttymodes
[i
].opcode
);
6444 ssh2_pkt_adduint32(pktout
, arg
);
6448 * Handle the SSH-2 userauth and connection layers.
6450 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
6451 struct Packet
*pktin
)
6453 struct do_ssh2_authconn_state
{
6455 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
6457 AUTH_KEYBOARD_INTERACTIVE
6461 AUTH_TYPE_PUBLICKEY
,
6462 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
6463 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
6465 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
6466 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
6468 int done_service_req
;
6469 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
6470 int tried_pubkey_config
, tried_agent
;
6471 int kbd_inter_running
, kbd_inter_refused
;
6473 int num_prompts
, curr_prompt
, echo
;
6478 void *publickey_blob
;
6479 int publickey_bloblen
;
6480 unsigned char request
[5], *response
, *p
;
6484 char *pkblob
, *alg
, *commentp
;
6485 int pklen
, alglen
, commentlen
;
6486 int siglen
, retlen
, len
;
6487 char *q
, *agentreq
, *ret
;
6489 int num_env
, env_left
, env_ok
;
6490 struct Packet
*pktout
;
6492 crState(do_ssh2_authconn_state
);
6494 crBegin(ssh
->do_ssh2_authconn_crstate
);
6496 s
->done_service_req
= FALSE
;
6497 s
->we_are_in
= FALSE
;
6498 if (!ssh
->cfg
.ssh_no_userauth
) {
6500 * Request userauth protocol, and await a response to it.
6502 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
6503 ssh2_pkt_addstring(s
->pktout
, "ssh-userauth");
6504 ssh2_pkt_send(ssh
, s
->pktout
);
6505 crWaitUntilV(pktin
);
6506 if (pktin
->type
== SSH2_MSG_SERVICE_ACCEPT
)
6507 s
->done_service_req
= TRUE
;
6509 if (!s
->done_service_req
) {
6511 * Request connection protocol directly, without authentication.
6513 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
6514 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");
6515 ssh2_pkt_send(ssh
, s
->pktout
);
6516 crWaitUntilV(pktin
);
6517 if (pktin
->type
== SSH2_MSG_SERVICE_ACCEPT
) {
6518 s
->we_are_in
= TRUE
; /* no auth required */
6520 bombout(("Server refused service request"));
6526 * We repeat this whole loop, including the username prompt,
6527 * until we manage a successful authentication. If the user
6528 * types the wrong _password_, they can be sent back to the
6529 * beginning to try another username, if this is configured on.
6530 * (If they specify a username in the config, they are never
6531 * asked, even if they do give a wrong password.)
6533 * I think this best serves the needs of
6535 * - the people who have no configuration, no keys, and just
6536 * want to try repeated (username,password) pairs until they
6537 * type both correctly
6539 * - people who have keys and configuration but occasionally
6540 * need to fall back to passwords
6542 * - people with a key held in Pageant, who might not have
6543 * logged in to a particular machine before; so they want to
6544 * type a username, and then _either_ their key will be
6545 * accepted, _or_ they will type a password. If they mistype
6546 * the username they will want to be able to get back and
6549 s
->username
[0] = '\0';
6550 s
->got_username
= FALSE
;
6551 bufchain_init(&ssh
->banner
);
6552 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] =
6553 ssh2_msg_userauth_banner
;
6554 while (!s
->we_are_in
) {
6558 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
6560 * We got a username last time round this loop, and
6561 * with change_username turned off we don't try to get
6564 } else if (!*ssh
->cfg
.username
) {
6565 if (ssh_get_line
&& !ssh_getline_pw_only
) {
6566 if (!ssh_get_line("login as: ",
6567 s
->username
, sizeof(s
->username
), FALSE
)) {
6569 * get_line failed to get a username.
6572 ssh_disconnect(ssh
, "No username provided", NULL
, 0, TRUE
);
6576 int ret
; /* need not be saved across crReturn */
6577 c_write_str(ssh
, "login as: ");
6579 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
6581 crWaitUntilV(!pktin
);
6582 ret
= process_userpass_input(ssh
, in
, inlen
);
6586 c_write_str(ssh
, "\r\n");
6588 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
6591 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
6592 s
->username
[sizeof(s
->username
)-1] = '\0';
6593 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
6594 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
6595 c_write_str(ssh
, stuff
);
6599 s
->got_username
= TRUE
;
6602 * Send an authentication request using method "none": (a)
6603 * just in case it succeeds, and (b) so that we know what
6604 * authentication methods we can usefully try next.
6606 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6608 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6609 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6610 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");/* service requested */
6611 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6612 ssh2_pkt_send(ssh
, s
->pktout
);
6613 s
->type
= AUTH_TYPE_NONE
;
6615 s
->we_are_in
= FALSE
;
6617 s
->tried_pubkey_config
= FALSE
;
6618 s
->tried_agent
= FALSE
;
6619 s
->kbd_inter_running
= FALSE
;
6620 s
->kbd_inter_refused
= FALSE
;
6621 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
6622 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
6624 logeventf(ssh
, "Reading private key file \"%.150s\"",
6625 filename_to_str(&ssh
->cfg
.keyfile
));
6626 keytype
= key_type(&ssh
->cfg
.keyfile
);
6627 if (keytype
== SSH_KEYTYPE_SSH2
) {
6629 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
6630 &s
->publickey_bloblen
, NULL
);
6633 logeventf(ssh
, "Unable to use this key file (%s)",
6634 key_type_to_str(keytype
));
6635 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
6637 filename_to_str(&ssh
->cfg
.keyfile
),
6638 key_type_to_str(keytype
));
6639 c_write_str(ssh
, msgbuf
);
6641 s
->publickey_blob
= NULL
;
6644 s
->publickey_blob
= NULL
;
6648 * Wait for the result of the last authentication request.
6651 crWaitUntilV(pktin
);
6653 * Now is a convenient point to spew any banner material
6654 * that we've accumulated. (This should ensure that when
6655 * we exit the auth loop, we haven't any left to deal
6659 int size
= bufchain_size(&ssh
->banner
);
6661 * Don't show the banner if we're operating in
6662 * non-verbose non-interactive mode. (It's probably
6663 * a script, which means nobody will read the
6664 * banner _anyway_, and moreover the printing of
6665 * the banner will screw up processing on the
6666 * output of (say) plink.)
6668 if (size
&& (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
))) {
6669 char *banner
= snewn(size
, char);
6670 bufchain_fetch(&ssh
->banner
, banner
, size
);
6671 c_write_untrusted(ssh
, banner
, size
);
6674 bufchain_clear(&ssh
->banner
);
6676 if (pktin
->type
== SSH2_MSG_USERAUTH_SUCCESS
) {
6677 logevent("Access granted");
6678 s
->we_are_in
= TRUE
;
6682 if (s
->kbd_inter_running
&&
6683 pktin
->type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6685 * This is either a further set-of-prompts packet
6686 * in keyboard-interactive authentication, or it's
6687 * the same one and we came back here with `gotit'
6688 * set. In the former case, we must reset the
6689 * curr_prompt variable.
6693 } else if (pktin
->type
== SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
) {
6694 /* FIXME: perhaps we should support this? */
6695 bombout(("PASSWD_CHANGEREQ not yet supported"));
6697 } else if (pktin
->type
!= SSH2_MSG_USERAUTH_FAILURE
) {
6698 bombout(("Strange packet received during authentication: type %d",
6706 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6707 * we can look at the string in it and know what we can
6708 * helpfully try next.
6710 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
) {
6713 ssh_pkt_getstring(pktin
, &methods
, &methlen
);
6714 s
->kbd_inter_running
= FALSE
;
6715 if (!ssh2_pkt_getbool(pktin
)) {
6717 * We have received an unequivocal Access
6718 * Denied. This can translate to a variety of
6721 * - if we'd just tried "none" authentication,
6722 * it's not worth printing anything at all
6724 * - if we'd just tried a public key _offer_,
6725 * the message should be "Server refused our
6726 * key" (or no message at all if the key
6727 * came from Pageant)
6729 * - if we'd just tried anything else, the
6730 * message really should be "Access denied".
6732 * Additionally, if we'd just tried password
6733 * authentication, we should break out of this
6734 * whole loop so as to go back to the username
6735 * prompt (iff we're configured to allow
6736 * username change attempts).
6738 if (s
->type
== AUTH_TYPE_NONE
) {
6740 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
6741 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
6742 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
6743 c_write_str(ssh
, "Server refused our key\r\n");
6744 logevent("Server refused public key");
6745 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
6746 /* server declined keyboard-interactive; ignore */
6748 c_write_str(ssh
, "Access denied\r\n");
6749 logevent("Access denied");
6750 if (s
->type
== AUTH_TYPE_PASSWORD
&&
6751 ssh
->cfg
.change_username
) {
6752 /* XXX perhaps we should allow
6753 * keyboard-interactive to do this too? */
6754 s
->we_are_in
= FALSE
;
6759 c_write_str(ssh
, "Further authentication required\r\n");
6760 logevent("Further authentication required");
6764 in_commasep_string("publickey", methods
, methlen
);
6766 in_commasep_string("password", methods
, methlen
);
6767 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
6768 in_commasep_string("keyboard-interactive", methods
, methlen
);
6772 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6776 * Most password/passphrase prompts will be
6777 * non-echoing, so we set this to 0 by default.
6778 * Exception is that some keyboard-interactive prompts
6779 * can be echoing, in which case we'll set this to 1.
6783 if (!s
->method
&& s
->can_pubkey
&&
6784 agent_exists() && !s
->tried_agent
) {
6786 * Attempt public-key authentication using Pageant.
6791 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6792 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6794 s
->tried_agent
= TRUE
;
6796 logevent("Pageant is running. Requesting keys.");
6798 /* Request the keys held by the agent. */
6799 PUT_32BIT(s
->request
, 1);
6800 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
6801 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
6802 ssh_agent_callback
, ssh
)) {
6806 bombout(("Unexpected data from server while"
6807 " waiting for agent response"));
6810 } while (pktin
|| inlen
> 0);
6811 r
= ssh
->agent_response
;
6812 s
->responselen
= ssh
->agent_response_len
;
6814 s
->response
= (unsigned char *) r
;
6815 if (s
->response
&& s
->responselen
>= 5 &&
6816 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
6817 s
->p
= s
->response
+ 5;
6818 s
->nkeys
= GET_32BIT(s
->p
);
6820 logeventf(ssh
, "Pageant has %d SSH-2 keys", s
->nkeys
);
6821 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
6824 logeventf(ssh
, "Trying Pageant key #%d", s
->keyi
);
6825 s
->pklen
= GET_32BIT(s
->p
);
6827 if (s
->publickey_blob
&&
6828 s
->pklen
== s
->publickey_bloblen
&&
6829 !memcmp(s
->p
, s
->publickey_blob
,
6830 s
->publickey_bloblen
)) {
6831 logevent("This key matches configured key file");
6832 s
->tried_pubkey_config
= 1;
6834 s
->pkblob
= (char *)s
->p
;
6836 s
->alglen
= GET_32BIT(s
->pkblob
);
6837 s
->alg
= s
->pkblob
+ 4;
6838 s
->commentlen
= GET_32BIT(s
->p
);
6840 s
->commentp
= (char *)s
->p
;
6841 s
->p
+= s
->commentlen
;
6842 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6843 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6844 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6845 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6846 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6847 ssh2_pkt_addstring_start(s
->pktout
);
6848 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6849 ssh2_pkt_addstring_start(s
->pktout
);
6850 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6851 ssh2_pkt_send(ssh
, s
->pktout
);
6853 crWaitUntilV(pktin
);
6854 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6855 logevent("Key refused");
6859 if (flags
& FLAG_VERBOSE
) {
6860 c_write_str(ssh
, "Authenticating with "
6862 c_write(ssh
, s
->commentp
, s
->commentlen
);
6863 c_write_str(ssh
, "\" from agent\r\n");
6867 * Server is willing to accept the key.
6868 * Construct a SIGN_REQUEST.
6870 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6871 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6872 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6873 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6874 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6875 ssh2_pkt_addstring_start(s
->pktout
);
6876 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6877 ssh2_pkt_addstring_start(s
->pktout
);
6878 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6880 s
->siglen
= s
->pktout
->length
- 5 + 4 + 20;
6881 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6883 s
->len
= 1; /* message type */
6884 s
->len
+= 4 + s
->pklen
; /* key blob */
6885 s
->len
+= 4 + s
->siglen
; /* data to sign */
6886 s
->len
+= 4; /* flags */
6887 s
->agentreq
= snewn(4 + s
->len
, char);
6888 PUT_32BIT(s
->agentreq
, s
->len
);
6889 s
->q
= s
->agentreq
+ 4;
6890 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
6891 PUT_32BIT(s
->q
, s
->pklen
);
6893 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
6895 PUT_32BIT(s
->q
, s
->siglen
);
6897 /* Now the data to be signed... */
6898 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6899 PUT_32BIT(s
->q
, 20);
6902 memcpy(s
->q
, ssh
->v2_session_id
, 20);
6904 memcpy(s
->q
, s
->pktout
->data
+ 5,
6905 s
->pktout
->length
- 5);
6906 s
->q
+= s
->pktout
->length
- 5;
6907 /* And finally the (zero) flags word. */
6909 if (!agent_query(s
->agentreq
, s
->len
+ 4,
6911 ssh_agent_callback
, ssh
)) {
6915 bombout(("Unexpected data from server"
6916 " while waiting for agent"
6920 } while (pktin
|| inlen
> 0);
6921 vret
= ssh
->agent_response
;
6922 s
->retlen
= ssh
->agent_response_len
;
6927 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
6928 logevent("Sending Pageant's response");
6929 ssh2_add_sigblob(ssh
, s
->pktout
,
6930 s
->pkblob
, s
->pklen
,
6932 GET_32BIT(s
->ret
+ 5));
6933 ssh2_pkt_send(ssh
, s
->pktout
);
6938 ("Pageant failed to answer challenge");
6949 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
6950 && !s
->tried_pubkey_config
) {
6951 unsigned char *pub_blob
;
6952 char *algorithm
, *comment
;
6955 s
->tried_pubkey_config
= TRUE
;
6957 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6958 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6961 * Try the public key supplied in the configuration.
6963 * First, offer the public blob to see if the server is
6964 * willing to accept it.
6967 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
6972 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6973 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6974 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6975 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6976 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6977 ssh2_pkt_addstring(s
->pktout
, algorithm
);
6978 ssh2_pkt_addstring_start(s
->pktout
);
6979 ssh2_pkt_addstring_data(s
->pktout
, (char *)pub_blob
,
6981 ssh2_pkt_send(ssh
, s
->pktout
);
6982 logevent("Offered public key");
6984 crWaitUntilV(pktin
);
6985 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6987 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
6988 continue; /* key refused; give up on it */
6991 logevent("Offer of public key accepted");
6993 * Actually attempt a serious authentication using
6996 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
6997 sprintf(s
->pwprompt
,
6998 "Passphrase for key \"%.100s\": ",
7004 if (flags
& FLAG_VERBOSE
) {
7005 c_write_str(ssh
, "Authenticating with public key \"");
7006 c_write_str(ssh
, comment
);
7007 c_write_str(ssh
, "\"\r\n");
7009 s
->method
= AUTH_PUBLICKEY_FILE
;
7013 if (!s
->method
&& s
->can_keyb_inter
&& !s
->kbd_inter_refused
&&
7014 !s
->kbd_inter_running
) {
7015 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
7016 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
7018 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
7019 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
7021 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
7022 ssh2_pkt_addstring(s
->pktout
, s
->username
);
7023 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
7024 ssh2_pkt_addstring(s
->pktout
, "keyboard-interactive"); /* method */
7025 ssh2_pkt_addstring(s
->pktout
, ""); /* lang */
7026 ssh2_pkt_addstring(s
->pktout
, "");
7027 ssh2_pkt_send(ssh
, s
->pktout
);
7029 crWaitUntilV(pktin
);
7030 if (pktin
->type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
7031 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
)
7033 logevent("Keyboard-interactive authentication refused");
7034 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
7035 s
->kbd_inter_refused
= TRUE
; /* don't try it again */
7039 c_write_str(ssh
, "Using keyboard-interactive authentication.\r\n");
7040 s
->kbd_inter_running
= TRUE
;
7044 if (s
->kbd_inter_running
) {
7045 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
7046 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
7048 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
7049 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
7051 if (s
->curr_prompt
== 0) {
7053 * We've got a fresh USERAUTH_INFO_REQUEST.
7054 * Display header data, and start going through
7057 char *name
, *inst
, *lang
;
7058 int name_len
, inst_len
, lang_len
;
7060 ssh_pkt_getstring(pktin
, &name
, &name_len
);
7061 ssh_pkt_getstring(pktin
, &inst
, &inst_len
);
7062 ssh_pkt_getstring(pktin
, &lang
, &lang_len
);
7064 c_write_untrusted(ssh
, name
, name_len
);
7065 c_write_str(ssh
, "\r\n");
7068 c_write_untrusted(ssh
, inst
, inst_len
);
7069 c_write_str(ssh
, "\r\n");
7071 s
->num_prompts
= ssh_pkt_getuint32(pktin
);
7075 * If there are prompts remaining in the packet,
7076 * display one and get a response.
7078 if (s
->curr_prompt
< s
->num_prompts
) {
7082 ssh_pkt_getstring(pktin
, &prompt
, &prompt_len
);
7083 if (prompt_len
> 0) {
7084 static const char trunc
[] = "<prompt truncated>: ";
7085 static const int prlen
= sizeof(s
->pwprompt
) -
7087 if (prompt_len
> prlen
) {
7088 memcpy(s
->pwprompt
, prompt
, prlen
);
7089 strcpy(s
->pwprompt
+ prlen
, trunc
);
7091 memcpy(s
->pwprompt
, prompt
, prompt_len
);
7092 s
->pwprompt
[prompt_len
] = '\0';
7096 "<server failed to send prompt>: ");
7098 s
->echo
= ssh2_pkt_getbool(pktin
);
7104 if (!s
->method
&& s
->can_passwd
) {
7105 s
->method
= AUTH_PASSWORD
;
7106 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
7107 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
7108 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
7115 if (!ssh_get_line(s
->pwprompt
, s
->password
,
7116 sizeof(s
->password
), TRUE
)) {
7118 * get_line failed to get a password (for
7119 * example because one was supplied on the
7120 * command line which has already failed to
7123 ssh_disconnect(ssh
, NULL
, "Unable to authenticate",
7124 SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER
,
7129 int ret
; /* need not be saved across crReturn */
7130 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
7133 setup_userpass_input(ssh
, s
->password
,
7134 sizeof(s
->password
), s
->echo
);
7136 crWaitUntilV(!pktin
);
7137 ret
= process_userpass_input(ssh
, in
, inlen
);
7141 c_write_str(ssh
, "\r\n");
7145 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
7147 * We have our passphrase. Now try the actual authentication.
7149 struct ssh2_userkey
*key
;
7150 const char *error
= NULL
;
7152 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
,
7154 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
7155 if (key
== SSH2_WRONG_PASSPHRASE
) {
7156 c_write_str(ssh
, "Wrong passphrase\r\n");
7157 s
->tried_pubkey_config
= FALSE
;
7159 c_write_str(ssh
, "Unable to load private key (");
7160 c_write_str(ssh
, error
);
7161 c_write_str(ssh
, ")\r\n");
7162 s
->tried_pubkey_config
= TRUE
;
7164 /* Send a spurious AUTH_NONE to return to the top. */
7165 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
7166 ssh2_pkt_addstring(s
->pktout
, s
->username
);
7167 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
7168 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
7169 ssh2_pkt_send(ssh
, s
->pktout
);
7170 s
->type
= AUTH_TYPE_NONE
;
7172 unsigned char *pkblob
, *sigblob
, *sigdata
;
7173 int pkblob_len
, sigblob_len
, sigdata_len
;
7177 * We have loaded the private key and the server
7178 * has announced that it's willing to accept it.
7179 * Hallelujah. Generate a signature and send it.
7181 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
7182 ssh2_pkt_addstring(s
->pktout
, s
->username
);
7183 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
7184 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
7185 ssh2_pkt_addbool(s
->pktout
, TRUE
);
7186 ssh2_pkt_addstring(s
->pktout
, key
->alg
->name
);
7187 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
7188 ssh2_pkt_addstring_start(s
->pktout
);
7189 ssh2_pkt_addstring_data(s
->pktout
, (char *)pkblob
, pkblob_len
);
7192 * The data to be signed is:
7196 * followed by everything so far placed in the
7199 sigdata_len
= s
->pktout
->length
- 5 + 4 + 20;
7200 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
7202 sigdata
= snewn(sigdata_len
, unsigned char);
7204 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
7205 PUT_32BIT(sigdata
+p
, 20);
7208 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
7209 memcpy(sigdata
+p
, s
->pktout
->data
+ 5,
7210 s
->pktout
->length
- 5);
7211 p
+= s
->pktout
->length
- 5;
7212 assert(p
== sigdata_len
);
7213 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
7214 sigdata_len
, &sigblob_len
);
7215 ssh2_add_sigblob(ssh
, s
->pktout
, pkblob
, pkblob_len
,
7216 sigblob
, sigblob_len
);
7221 ssh2_pkt_send(ssh
, s
->pktout
);
7222 s
->type
= AUTH_TYPE_PUBLICKEY
;
7223 key
->alg
->freekey(key
->data
);
7225 } else if (s
->method
== AUTH_PASSWORD
) {
7227 * We pad out the password packet to 256 bytes to make
7228 * it harder for an attacker to find the length of the
7231 * Anyone using a password longer than 256 bytes
7232 * probably doesn't have much to worry about from
7233 * people who find out how long their password is!
7235 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
7236 s
->pktout
->forcepad
= 256;
7237 ssh2_pkt_addstring(s
->pktout
, s
->username
);
7238 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
7239 ssh2_pkt_addstring(s
->pktout
, "password");
7240 ssh2_pkt_addbool(s
->pktout
, FALSE
);
7241 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
7242 ssh2_pkt_addstring(s
->pktout
, s
->password
);
7243 memset(s
->password
, 0, sizeof(s
->password
));
7244 end_log_omission(ssh
, s
->pktout
);
7245 ssh2_pkt_send(ssh
, s
->pktout
);
7246 logevent("Sent password");
7247 s
->type
= AUTH_TYPE_PASSWORD
;
7248 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
7249 if (s
->curr_prompt
== 0) {
7250 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
7251 s
->pktout
->forcepad
= 256;
7252 ssh2_pkt_adduint32(s
->pktout
, s
->num_prompts
);
7254 if (s
->need_pw
) { /* only add pw if we just got one! */
7255 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
7256 ssh2_pkt_addstring(s
->pktout
, s
->password
);
7257 memset(s
->password
, 0, sizeof(s
->password
));
7258 end_log_omission(ssh
, s
->pktout
);
7261 if (s
->curr_prompt
>= s
->num_prompts
) {
7262 ssh2_pkt_send(ssh
, s
->pktout
);
7265 * If there are prompts remaining, we set
7266 * `gotit' so that we won't attempt to get
7267 * another packet. Then we go back round the
7268 * loop and will end up retrieving another
7269 * prompt out of the existing packet. Funky or
7274 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
7276 ssh_disconnect(ssh
, NULL
,
7277 "No supported authentication methods available",
7278 SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE
,
7284 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
7287 * Now the connection protocol has started, one way or another.
7290 ssh
->channels
= newtree234(ssh_channelcmp
);
7293 * Set up handlers for some connection protocol messages, so we
7294 * don't have to handle them repeatedly in this coroutine.
7296 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] =
7297 ssh2_msg_channel_window_adjust
;
7298 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] =
7299 ssh2_msg_global_request
;
7302 * Create the main session channel.
7304 if (!ssh
->cfg
.ssh_no_shell
) {
7305 ssh
->mainchan
= snew(struct ssh_channel
);
7306 ssh
->mainchan
->ssh
= ssh
;
7307 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
7308 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
7309 ssh2_pkt_addstring(s
->pktout
, "session");
7310 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->localid
);
7311 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7312 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
7313 ssh2_pkt_adduint32(s
->pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
7314 ssh2_pkt_send(ssh
, s
->pktout
);
7315 crWaitUntilV(pktin
);
7316 if (pktin
->type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
7317 bombout(("Server refused to open a session"));
7319 /* FIXME: error data comes back in FAILURE packet */
7321 if (ssh_pkt_getuint32(pktin
) != ssh
->mainchan
->localid
) {
7322 bombout(("Server's channel confirmation cited wrong channel"));
7325 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(pktin
);
7326 ssh
->mainchan
->halfopen
= FALSE
;
7327 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
7328 ssh
->mainchan
->closes
= 0;
7329 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
7330 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
7331 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
7332 add234(ssh
->channels
, ssh
->mainchan
);
7333 update_specials_menu(ssh
->frontend
);
7334 logevent("Opened channel for session");
7336 ssh
->mainchan
= NULL
;
7339 * Now we have a channel, make dispatch table entries for
7340 * general channel-based messages.
7342 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] =
7343 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] =
7344 ssh2_msg_channel_data
;
7345 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = ssh2_msg_channel_eof
;
7346 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = ssh2_msg_channel_close
;
7347 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] =
7348 ssh2_msg_channel_open_confirmation
;
7349 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] =
7350 ssh2_msg_channel_open_failure
;
7351 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] =
7352 ssh2_msg_channel_request
;
7353 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] =
7354 ssh2_msg_channel_open
;
7357 * Potentially enable X11 forwarding.
7359 if (ssh
->mainchan
&& ssh
->cfg
.x11_forward
) {
7360 char proto
[20], data
[64];
7361 logevent("Requesting X11 forwarding");
7362 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
7363 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
7364 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
7365 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7366 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7367 ssh2_pkt_addstring(s
->pktout
, "x11-req");
7368 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7369 ssh2_pkt_addbool(s
->pktout
, 0); /* many connections */
7370 ssh2_pkt_addstring(s
->pktout
, proto
);
7372 * Note that while we blank the X authentication data here, we don't
7373 * take any special action to blank the start of an X11 channel,
7374 * so using MIT-MAGIC-COOKIE-1 and actually opening an X connection
7375 * without having session blanking enabled is likely to leak your
7376 * cookie into the log.
7378 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
7379 ssh2_pkt_addstring(s
->pktout
, data
);
7380 end_log_omission(ssh
, s
->pktout
);
7381 ssh2_pkt_adduint32(s
->pktout
, x11_get_screen_number(ssh
->cfg
.x11_display
));
7382 ssh2_pkt_send(ssh
, s
->pktout
);
7384 crWaitUntilV(pktin
);
7386 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7387 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7388 bombout(("Unexpected response to X11 forwarding request:"
7389 " packet type %d", pktin
->type
));
7392 logevent("X11 forwarding refused");
7394 logevent("X11 forwarding enabled");
7395 ssh
->X11_fwd_enabled
= TRUE
;
7400 * Enable port forwardings.
7402 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
7405 * Potentially enable agent forwarding.
7407 if (ssh
->mainchan
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
7408 logevent("Requesting OpenSSH-style agent forwarding");
7409 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7410 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7411 ssh2_pkt_addstring(s
->pktout
, "auth-agent-req@openssh.com");
7412 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7413 ssh2_pkt_send(ssh
, s
->pktout
);
7415 crWaitUntilV(pktin
);
7417 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7418 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7419 bombout(("Unexpected response to agent forwarding request:"
7420 " packet type %d", pktin
->type
));
7423 logevent("Agent forwarding refused");
7425 logevent("Agent forwarding enabled");
7426 ssh
->agentfwd_enabled
= TRUE
;
7431 * Now allocate a pty for the session.
7433 if (ssh
->mainchan
&& !ssh
->cfg
.nopty
) {
7434 /* Unpick the terminal-speed string. */
7435 /* XXX perhaps we should allow no speeds to be sent. */
7436 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
7437 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
7438 /* Build the pty request. */
7439 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7440 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7441 ssh2_pkt_addstring(s
->pktout
, "pty-req");
7442 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7443 ssh2_pkt_addstring(s
->pktout
, ssh
->cfg
.termtype
);
7444 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_width
);
7445 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_height
);
7446 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel width */
7447 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel height */
7448 ssh2_pkt_addstring_start(s
->pktout
);
7449 parse_ttymodes(ssh
, ssh
->cfg
.ttymodes
,
7450 ssh2_send_ttymode
, (void *)s
->pktout
);
7451 ssh2_pkt_addbyte(s
->pktout
, SSH2_TTY_OP_ISPEED
);
7452 ssh2_pkt_adduint32(s
->pktout
, ssh
->ispeed
);
7453 ssh2_pkt_addbyte(s
->pktout
, SSH2_TTY_OP_OSPEED
);
7454 ssh2_pkt_adduint32(s
->pktout
, ssh
->ospeed
);
7455 ssh2_pkt_addstring_data(s
->pktout
, "\0", 1); /* TTY_OP_END */
7456 ssh2_pkt_send(ssh
, s
->pktout
);
7457 ssh
->state
= SSH_STATE_INTERMED
;
7459 crWaitUntilV(pktin
);
7461 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7462 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7463 bombout(("Unexpected response to pty request:"
7464 " packet type %d", pktin
->type
));
7467 c_write_str(ssh
, "Server refused to allocate pty\r\n");
7468 ssh
->editing
= ssh
->echoing
= 1;
7470 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
7471 ssh
->ospeed
, ssh
->ispeed
);
7474 ssh
->editing
= ssh
->echoing
= 1;
7478 * Send environment variables.
7480 * Simplest thing here is to send all the requests at once, and
7481 * then wait for a whole bunch of successes or failures.
7483 if (ssh
->mainchan
&& *ssh
->cfg
.environmt
) {
7484 char *e
= ssh
->cfg
.environmt
;
7485 char *var
, *varend
, *val
;
7491 while (*e
&& *e
!= '\t') e
++;
7493 if (*e
== '\t') e
++;
7498 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7499 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7500 ssh2_pkt_addstring(s
->pktout
, "env");
7501 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7502 ssh2_pkt_addstring_start(s
->pktout
);
7503 ssh2_pkt_addstring_data(s
->pktout
, var
, varend
-var
);
7504 ssh2_pkt_addstring(s
->pktout
, val
);
7505 ssh2_pkt_send(ssh
, s
->pktout
);
7510 logeventf(ssh
, "Sent %d environment variables", s
->num_env
);
7513 s
->env_left
= s
->num_env
;
7515 while (s
->env_left
> 0) {
7516 crWaitUntilV(pktin
);
7518 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7519 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7520 bombout(("Unexpected response to environment request:"
7521 " packet type %d", pktin
->type
));
7531 if (s
->env_ok
== s
->num_env
) {
7532 logevent("All environment variables successfully set");
7533 } else if (s
->env_ok
== 0) {
7534 logevent("All environment variables refused");
7535 c_write_str(ssh
, "Server refused to set environment variables\r\n");
7537 logeventf(ssh
, "%d environment variables refused",
7538 s
->num_env
- s
->env_ok
);
7539 c_write_str(ssh
, "Server refused to set all environment variables\r\n");
7544 * Start a shell or a remote command. We may have to attempt
7545 * this twice if the config data has provided a second choice
7548 if (ssh
->mainchan
) while (1) {
7552 if (ssh
->fallback_cmd
) {
7553 subsys
= ssh
->cfg
.ssh_subsys2
;
7554 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
7556 subsys
= ssh
->cfg
.ssh_subsys
;
7557 cmd
= ssh
->cfg
.remote_cmd_ptr
;
7558 if (!cmd
) cmd
= ssh
->cfg
.remote_cmd
;
7561 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7562 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7564 ssh2_pkt_addstring(s
->pktout
, "subsystem");
7565 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7566 ssh2_pkt_addstring(s
->pktout
, cmd
);
7568 ssh2_pkt_addstring(s
->pktout
, "exec");
7569 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7570 ssh2_pkt_addstring(s
->pktout
, cmd
);
7572 ssh2_pkt_addstring(s
->pktout
, "shell");
7573 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7575 ssh2_pkt_send(ssh
, s
->pktout
);
7577 crWaitUntilV(pktin
);
7579 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7580 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7581 bombout(("Unexpected response to shell/command request:"
7582 " packet type %d", pktin
->type
));
7586 * We failed to start the command. If this is the
7587 * fallback command, we really are finished; if it's
7588 * not, and if the fallback command exists, try falling
7589 * back to it before complaining.
7591 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
7592 logevent("Primary command failed; attempting fallback");
7593 ssh
->fallback_cmd
= TRUE
;
7596 bombout(("Server refused to start a shell/command"));
7599 logevent("Started a shell/command");
7604 ssh
->state
= SSH_STATE_SESSION
;
7605 if (ssh
->size_needed
)
7606 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
7607 if (ssh
->eof_needed
)
7608 ssh_special(ssh
, TS_EOF
);
7614 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
7619 s
->try_send
= FALSE
;
7623 * _All_ the connection-layer packets we expect to
7624 * receive are now handled by the dispatch table.
7625 * Anything that reaches here must be bogus.
7628 bombout(("Strange packet received: type %d", pktin
->type
));
7630 } else if (ssh
->mainchan
) {
7632 * We have spare data. Add it to the channel buffer.
7634 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
7639 struct ssh_channel
*c
;
7641 * Try to send data on all channels if we can.
7643 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++)
7644 ssh2_try_send_and_unthrottle(c
);
7652 * Handlers for SSH-2 messages that might arrive at any moment.
7654 static void ssh2_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
7656 /* log reason code in disconnect message */
7658 int nowlen
, reason
, msglen
;
7660 reason
= ssh_pkt_getuint32(pktin
);
7661 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7663 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
7664 buf
= dupprintf("Received disconnect message (%s)",
7665 ssh2_disconnect_reasons
[reason
]);
7667 buf
= dupprintf("Received disconnect message (unknown"
7668 " type %d)", reason
);
7672 buf
= dupprintf("Disconnection message text: %n%.*s",
7673 &nowlen
, msglen
, msg
);
7675 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7677 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
7678 ssh2_disconnect_reasons
[reason
] : "unknown",
7683 static void ssh2_msg_debug(Ssh ssh
, struct Packet
*pktin
)
7685 /* log the debug message */
7690 /* XXX maybe we should actually take notice of this */
7691 always_display
= ssh2_pkt_getbool(pktin
);
7692 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7694 logeventf(ssh
, "Remote debug message: %.*s", msglen
, msg
);
7697 static void ssh2_msg_something_unimplemented(Ssh ssh
, struct Packet
*pktin
)
7699 struct Packet
*pktout
;
7700 pktout
= ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
7701 ssh2_pkt_adduint32(pktout
, pktin
->sequence
);
7703 * UNIMPLEMENTED messages MUST appear in the same order as the
7704 * messages they respond to. Hence, never queue them.
7706 ssh2_pkt_send_noqueue(ssh
, pktout
);
7710 * Handle the top-level SSH-2 protocol.
7712 static void ssh2_protocol_setup(Ssh ssh
)
7717 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7719 for (i
= 0; i
< 256; i
++)
7720 ssh
->packet_dispatch
[i
] = ssh2_msg_something_unimplemented
;
7723 * Any message we actually understand, we set to NULL so that
7724 * the coroutines will get it.
7726 ssh
->packet_dispatch
[SSH2_MSG_UNIMPLEMENTED
] = NULL
;
7727 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_REQUEST
] = NULL
;
7728 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_ACCEPT
] = NULL
;
7729 ssh
->packet_dispatch
[SSH2_MSG_KEXINIT
] = NULL
;
7730 ssh
->packet_dispatch
[SSH2_MSG_NEWKEYS
] = NULL
;
7731 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_INIT
] = NULL
;
7732 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_REPLY
] = NULL
;
7733 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7734 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7735 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_INIT
] = NULL
;
7736 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_REPLY
] = NULL
;
7737 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_REQUEST
] = NULL
;
7738 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_FAILURE
] = NULL
;
7739 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_SUCCESS
] = NULL
;
7740 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
7741 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_PK_OK
] = NULL
;
7742 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7743 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7744 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_INFO_RESPONSE
] = NULL
;
7745 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] = NULL
;
7746 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_SUCCESS
] = NULL
;
7747 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_FAILURE
] = NULL
;
7748 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] = NULL
;
7749 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] = NULL
;
7750 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] = NULL
;
7751 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] = NULL
;
7752 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] = NULL
;
7753 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] = NULL
;
7754 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = NULL
;
7755 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = NULL
;
7756 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] = NULL
;
7757 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_SUCCESS
] = NULL
;
7758 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_FAILURE
] = NULL
;
7761 * These special message types we install handlers for.
7763 ssh
->packet_dispatch
[SSH2_MSG_DISCONNECT
] = ssh2_msg_disconnect
;
7764 ssh
->packet_dispatch
[SSH2_MSG_IGNORE
] = ssh_msg_ignore
; /* shared with SSH-1 */
7765 ssh
->packet_dispatch
[SSH2_MSG_DEBUG
] = ssh2_msg_debug
;
7768 static void ssh2_timer(void *ctx
, long now
)
7772 if (ssh
->state
== SSH_STATE_CLOSED
)
7775 if (!ssh
->kex_in_progress
&& ssh
->cfg
.ssh_rekey_time
!= 0 &&
7776 now
- ssh
->next_rekey
>= 0) {
7777 do_ssh2_transport(ssh
, "timeout", -1, NULL
);
7781 static void ssh2_protocol(Ssh ssh
, void *vin
, int inlen
,
7782 struct Packet
*pktin
)
7784 unsigned char *in
= (unsigned char *)vin
;
7785 if (ssh
->state
== SSH_STATE_CLOSED
)
7789 ssh
->incoming_data_size
+= pktin
->encrypted_len
;
7790 if (!ssh
->kex_in_progress
&&
7791 ssh
->max_data_size
!= 0 &&
7792 ssh
->incoming_data_size
> ssh
->max_data_size
)
7793 do_ssh2_transport(ssh
, "too much data received", -1, NULL
);
7796 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
7797 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
7801 if (!ssh
->protocol_initial_phase_done
||
7802 (pktin
&& pktin
->type
>= 20 && pktin
->type
< 50)) {
7803 if (do_ssh2_transport(ssh
, in
, inlen
, pktin
) &&
7804 !ssh
->protocol_initial_phase_done
) {
7805 ssh
->protocol_initial_phase_done
= TRUE
;
7807 * Allow authconn to initialise itself.
7809 do_ssh2_authconn(ssh
, NULL
, 0, NULL
);
7812 do_ssh2_authconn(ssh
, in
, inlen
, pktin
);
7817 * Called to set up the connection.
7819 * Returns an error message, or NULL on success.
7821 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
7823 char *host
, int port
, char **realhost
, int nodelay
,
7829 ssh
= snew(struct ssh_tag
);
7830 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7831 ssh
->version
= 0; /* when not ready yet */
7834 ssh
->v1_cipher_ctx
= NULL
;
7835 ssh
->crcda_ctx
= NULL
;
7836 ssh
->cscipher
= NULL
;
7837 ssh
->cs_cipher_ctx
= NULL
;
7838 ssh
->sccipher
= NULL
;
7839 ssh
->sc_cipher_ctx
= NULL
;
7841 ssh
->cs_mac_ctx
= NULL
;
7843 ssh
->sc_mac_ctx
= NULL
;
7845 ssh
->cs_comp_ctx
= NULL
;
7847 ssh
->sc_comp_ctx
= NULL
;
7849 ssh
->kex_ctx
= NULL
;
7850 ssh
->hostkey
= NULL
;
7852 ssh
->close_expected
= FALSE
;
7853 ssh
->clean_exit
= FALSE
;
7854 ssh
->state
= SSH_STATE_PREPACKET
;
7855 ssh
->size_needed
= FALSE
;
7856 ssh
->eof_needed
= FALSE
;
7859 ssh
->deferred_send_data
= NULL
;
7860 ssh
->deferred_len
= 0;
7861 ssh
->deferred_size
= 0;
7862 ssh
->fallback_cmd
= 0;
7864 ssh
->x11auth
= NULL
;
7865 ssh
->v1_compressing
= FALSE
;
7866 ssh
->v2_outgoing_sequence
= 0;
7867 ssh
->ssh1_rdpkt_crstate
= 0;
7868 ssh
->ssh2_rdpkt_crstate
= 0;
7869 ssh
->do_ssh_init_crstate
= 0;
7870 ssh
->ssh_gotdata_crstate
= 0;
7871 ssh
->do_ssh1_connection_crstate
= 0;
7872 ssh
->do_ssh1_login_crstate
= 0;
7873 ssh
->do_ssh2_transport_crstate
= 0;
7874 ssh
->do_ssh2_authconn_crstate
= 0;
7875 ssh
->do_ssh_init_state
= NULL
;
7876 ssh
->do_ssh1_login_state
= NULL
;
7877 ssh
->do_ssh2_transport_state
= NULL
;
7878 ssh
->do_ssh2_authconn_state
= NULL
;
7881 ssh
->mainchan
= NULL
;
7882 ssh
->throttled_all
= 0;
7883 ssh
->v1_stdout_throttling
= 0;
7885 ssh
->queuelen
= ssh
->queuesize
= 0;
7886 ssh
->queueing
= FALSE
;
7887 ssh
->qhead
= ssh
->qtail
= NULL
;
7888 ssh
->deferred_rekey_reason
= NULL
;
7889 bufchain_init(&ssh
->queued_incoming_data
);
7890 ssh
->frozen
= FALSE
;
7892 *backend_handle
= ssh
;
7895 if (crypto_startup() == 0)
7896 return "Microsoft high encryption pack not installed!";
7899 ssh
->frontend
= frontend_handle
;
7900 ssh
->term_width
= ssh
->cfg
.width
;
7901 ssh
->term_height
= ssh
->cfg
.height
;
7903 ssh
->channels
= NULL
;
7904 ssh
->rportfwds
= NULL
;
7905 ssh
->portfwds
= NULL
;
7910 ssh
->v1_throttle_count
= 0;
7911 ssh
->overall_bufsize
= 0;
7912 ssh
->fallback_cmd
= 0;
7914 ssh
->protocol
= NULL
;
7916 ssh
->protocol_initial_phase_done
= FALSE
;
7920 ssh
->incoming_data_size
= ssh
->outgoing_data_size
=
7921 ssh
->deferred_data_size
= 0L;
7922 ssh
->max_data_size
= parse_blocksize(ssh
->cfg
.ssh_rekey_data
);
7923 ssh
->kex_in_progress
= FALSE
;
7925 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
7934 static void ssh_free(void *handle
)
7936 Ssh ssh
= (Ssh
) handle
;
7937 struct ssh_channel
*c
;
7938 struct ssh_rportfwd
*pf
;
7940 if (ssh
->v1_cipher_ctx
)
7941 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
7942 if (ssh
->cs_cipher_ctx
)
7943 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
7944 if (ssh
->sc_cipher_ctx
)
7945 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
7946 if (ssh
->cs_mac_ctx
)
7947 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
7948 if (ssh
->sc_mac_ctx
)
7949 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
7950 if (ssh
->cs_comp_ctx
) {
7952 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
7954 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
7956 if (ssh
->sc_comp_ctx
) {
7958 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
7960 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
7963 dh_cleanup(ssh
->kex_ctx
);
7964 sfree(ssh
->savedhost
);
7966 while (ssh
->queuelen
-- > 0)
7967 ssh_free_packet(ssh
->queue
[ssh
->queuelen
]);
7970 while (ssh
->qhead
) {
7971 struct queued_handler
*qh
= ssh
->qhead
;
7972 ssh
->qhead
= qh
->next
;
7975 ssh
->qhead
= ssh
->qtail
= NULL
;
7977 if (ssh
->channels
) {
7978 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
7981 if (c
->u
.x11
.s
!= NULL
)
7982 x11_close(c
->u
.x11
.s
);
7985 if (c
->u
.pfd
.s
!= NULL
)
7986 pfd_close(c
->u
.pfd
.s
);
7991 freetree234(ssh
->channels
);
7992 ssh
->channels
= NULL
;
7995 if (ssh
->rportfwds
) {
7996 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
7998 freetree234(ssh
->rportfwds
);
7999 ssh
->rportfwds
= NULL
;
8001 sfree(ssh
->deferred_send_data
);
8003 x11_free_auth(ssh
->x11auth
);
8004 sfree(ssh
->do_ssh_init_state
);
8005 sfree(ssh
->do_ssh1_login_state
);
8006 sfree(ssh
->do_ssh2_transport_state
);
8007 sfree(ssh
->do_ssh2_authconn_state
);
8010 if (ssh
->crcda_ctx
) {
8011 crcda_free_context(ssh
->crcda_ctx
);
8012 ssh
->crcda_ctx
= NULL
;
8015 ssh_do_close(ssh
, TRUE
);
8016 expire_timer_context(ssh
);
8018 pinger_free(ssh
->pinger
);
8019 bufchain_clear(&ssh
->queued_incoming_data
);
8026 * Reconfigure the SSH backend.
8028 static void ssh_reconfig(void *handle
, Config
*cfg
)
8030 Ssh ssh
= (Ssh
) handle
;
8031 char *rekeying
= NULL
, rekey_mandatory
= FALSE
;
8032 unsigned long old_max_data_size
;
8034 pinger_reconfig(ssh
->pinger
, &ssh
->cfg
, cfg
);
8036 ssh_setup_portfwd(ssh
, cfg
);
8038 if (ssh
->cfg
.ssh_rekey_time
!= cfg
->ssh_rekey_time
&&
8039 cfg
->ssh_rekey_time
!= 0) {
8040 long new_next
= ssh
->last_rekey
+ cfg
->ssh_rekey_time
*60*TICKSPERSEC
;
8041 long now
= GETTICKCOUNT();
8043 if (new_next
- now
< 0) {
8044 rekeying
= "timeout shortened";
8046 ssh
->next_rekey
= schedule_timer(new_next
- now
, ssh2_timer
, ssh
);
8050 old_max_data_size
= ssh
->max_data_size
;
8051 ssh
->max_data_size
= parse_blocksize(cfg
->ssh_rekey_data
);
8052 if (old_max_data_size
!= ssh
->max_data_size
&&
8053 ssh
->max_data_size
!= 0) {
8054 if (ssh
->outgoing_data_size
> ssh
->max_data_size
||
8055 ssh
->incoming_data_size
> ssh
->max_data_size
)
8056 rekeying
= "data limit lowered";
8059 if (ssh
->cfg
.compression
!= cfg
->compression
) {
8060 rekeying
= "compression setting changed";
8061 rekey_mandatory
= TRUE
;
8064 if (ssh
->cfg
.ssh2_des_cbc
!= cfg
->ssh2_des_cbc
||
8065 memcmp(ssh
->cfg
.ssh_cipherlist
, cfg
->ssh_cipherlist
,
8066 sizeof(ssh
->cfg
.ssh_cipherlist
))) {
8067 rekeying
= "cipher settings changed";
8068 rekey_mandatory
= TRUE
;
8071 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
8074 if (!ssh
->kex_in_progress
) {
8075 do_ssh2_transport(ssh
, rekeying
, -1, NULL
);
8076 } else if (rekey_mandatory
) {
8077 ssh
->deferred_rekey_reason
= rekeying
;
8083 * Called to send data down the SSH connection.
8085 static int ssh_send(void *handle
, char *buf
, int len
)
8087 Ssh ssh
= (Ssh
) handle
;
8089 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
8092 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
8094 return ssh_sendbuffer(ssh
);
8098 * Called to query the current amount of buffered stdin data.
8100 static int ssh_sendbuffer(void *handle
)
8102 Ssh ssh
= (Ssh
) handle
;
8105 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
8109 * If the SSH socket itself has backed up, add the total backup
8110 * size on that to any individual buffer on the stdin channel.
8113 if (ssh
->throttled_all
)
8114 override_value
= ssh
->overall_bufsize
;
8116 if (ssh
->version
== 1) {
8117 return override_value
;
8118 } else if (ssh
->version
== 2) {
8119 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
8120 return override_value
;
8122 return (override_value
+
8123 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
8130 * Called to set the size of the window from SSH's POV.
8132 static void ssh_size(void *handle
, int width
, int height
)
8134 Ssh ssh
= (Ssh
) handle
;
8135 struct Packet
*pktout
;
8137 ssh
->term_width
= width
;
8138 ssh
->term_height
= height
;
8140 switch (ssh
->state
) {
8141 case SSH_STATE_BEFORE_SIZE
:
8142 case SSH_STATE_PREPACKET
:
8143 case SSH_STATE_CLOSED
:
8144 break; /* do nothing */
8145 case SSH_STATE_INTERMED
:
8146 ssh
->size_needed
= TRUE
; /* buffer for later */
8148 case SSH_STATE_SESSION
:
8149 if (!ssh
->cfg
.nopty
) {
8150 if (ssh
->version
== 1) {
8151 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
8152 PKT_INT
, ssh
->term_height
,
8153 PKT_INT
, ssh
->term_width
,
8154 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
8155 } else if (ssh
->mainchan
) {
8156 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
8157 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8158 ssh2_pkt_addstring(pktout
, "window-change");
8159 ssh2_pkt_addbool(pktout
, 0);
8160 ssh2_pkt_adduint32(pktout
, ssh
->term_width
);
8161 ssh2_pkt_adduint32(pktout
, ssh
->term_height
);
8162 ssh2_pkt_adduint32(pktout
, 0);
8163 ssh2_pkt_adduint32(pktout
, 0);
8164 ssh2_pkt_send(ssh
, pktout
);
8172 * Return a list of the special codes that make sense in this
8175 static const struct telnet_special
*ssh_get_specials(void *handle
)
8177 static const struct telnet_special ssh1_ignore_special
[] = {
8178 {"IGNORE message", TS_NOP
}
8180 static const struct telnet_special ssh2_transport_specials
[] = {
8181 {"IGNORE message", TS_NOP
},
8182 {"Repeat key exchange", TS_REKEY
},
8184 static const struct telnet_special ssh2_session_specials
[] = {
8187 /* These are the signal names defined by draft-ietf-secsh-connect-23.
8188 * They include all the ISO C signals, but are a subset of the POSIX
8189 * required signals. */
8190 {"SIGINT (Interrupt)", TS_SIGINT
},
8191 {"SIGTERM (Terminate)", TS_SIGTERM
},
8192 {"SIGKILL (Kill)", TS_SIGKILL
},
8193 {"SIGQUIT (Quit)", TS_SIGQUIT
},
8194 {"SIGHUP (Hangup)", TS_SIGHUP
},
8195 {"More signals", TS_SUBMENU
},
8196 {"SIGABRT", TS_SIGABRT
}, {"SIGALRM", TS_SIGALRM
},
8197 {"SIGFPE", TS_SIGFPE
}, {"SIGILL", TS_SIGILL
},
8198 {"SIGPIPE", TS_SIGPIPE
}, {"SIGSEGV", TS_SIGSEGV
},
8199 {"SIGUSR1", TS_SIGUSR1
}, {"SIGUSR2", TS_SIGUSR2
},
8202 static const struct telnet_special specials_end
[] = {
8205 /* XXX review this length for any changes: */
8206 static struct telnet_special ssh_specials
[lenof(ssh2_transport_specials
) +
8207 lenof(ssh2_session_specials
) +
8208 lenof(specials_end
)];
8209 Ssh ssh
= (Ssh
) handle
;
8211 #define ADD_SPECIALS(name) \
8213 assert((i + lenof(name)) <= lenof(ssh_specials)); \
8214 memcpy(&ssh_specials[i], name, sizeof name); \
8218 if (ssh
->version
== 1) {
8219 /* Don't bother offering IGNORE if we've decided the remote
8220 * won't cope with it, since we wouldn't bother sending it if
8222 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
8223 ADD_SPECIALS(ssh1_ignore_special
);
8224 } else if (ssh
->version
== 2) {
8225 ADD_SPECIALS(ssh2_transport_specials
);
8227 ADD_SPECIALS(ssh2_session_specials
);
8228 } /* else we're not ready yet */
8231 ADD_SPECIALS(specials_end
);
8232 return ssh_specials
;
8240 * Send special codes. TS_EOF is useful for `plink', so you
8241 * can send an EOF and collect resulting output (e.g. `plink
8244 static void ssh_special(void *handle
, Telnet_Special code
)
8246 Ssh ssh
= (Ssh
) handle
;
8247 struct Packet
*pktout
;
8249 if (code
== TS_EOF
) {
8250 if (ssh
->state
!= SSH_STATE_SESSION
) {
8252 * Buffer the EOF in case we are pre-SESSION, so we can
8253 * send it as soon as we reach SESSION.
8256 ssh
->eof_needed
= TRUE
;
8259 if (ssh
->version
== 1) {
8260 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
8261 } else if (ssh
->mainchan
) {
8262 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
8263 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8264 ssh2_pkt_send(ssh
, pktout
);
8265 ssh
->send_ok
= 0; /* now stop trying to read from stdin */
8267 logevent("Sent EOF message");
8268 } else if (code
== TS_PING
|| code
== TS_NOP
) {
8269 if (ssh
->state
== SSH_STATE_CLOSED
8270 || ssh
->state
== SSH_STATE_PREPACKET
) return;
8271 if (ssh
->version
== 1) {
8272 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
8273 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
8275 pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
8276 ssh2_pkt_addstring_start(pktout
);
8277 ssh2_pkt_send_noqueue(ssh
, pktout
);
8279 } else if (code
== TS_REKEY
) {
8280 if (!ssh
->kex_in_progress
&& ssh
->version
== 2) {
8281 do_ssh2_transport(ssh
, "at user request", -1, NULL
);
8283 } else if (code
== TS_BRK
) {
8284 if (ssh
->state
== SSH_STATE_CLOSED
8285 || ssh
->state
== SSH_STATE_PREPACKET
) return;
8286 if (ssh
->version
== 1) {
8287 logevent("Unable to send BREAK signal in SSH-1");
8288 } else if (ssh
->mainchan
) {
8289 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
8290 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8291 ssh2_pkt_addstring(pktout
, "break");
8292 ssh2_pkt_addbool(pktout
, 0);
8293 ssh2_pkt_adduint32(pktout
, 0); /* default break length */
8294 ssh2_pkt_send(ssh
, pktout
);
8297 /* Is is a POSIX signal? */
8298 char *signame
= NULL
;
8299 if (code
== TS_SIGABRT
) signame
= "ABRT";
8300 if (code
== TS_SIGALRM
) signame
= "ALRM";
8301 if (code
== TS_SIGFPE
) signame
= "FPE";
8302 if (code
== TS_SIGHUP
) signame
= "HUP";
8303 if (code
== TS_SIGILL
) signame
= "ILL";
8304 if (code
== TS_SIGINT
) signame
= "INT";
8305 if (code
== TS_SIGKILL
) signame
= "KILL";
8306 if (code
== TS_SIGPIPE
) signame
= "PIPE";
8307 if (code
== TS_SIGQUIT
) signame
= "QUIT";
8308 if (code
== TS_SIGSEGV
) signame
= "SEGV";
8309 if (code
== TS_SIGTERM
) signame
= "TERM";
8310 if (code
== TS_SIGUSR1
) signame
= "USR1";
8311 if (code
== TS_SIGUSR2
) signame
= "USR2";
8312 /* The SSH-2 protocol does in principle support arbitrary named
8313 * signals, including signame@domain, but we don't support those. */
8315 /* It's a signal. */
8316 if (ssh
->version
== 2 && ssh
->mainchan
) {
8317 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
8318 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8319 ssh2_pkt_addstring(pktout
, "signal");
8320 ssh2_pkt_addbool(pktout
, 0);
8321 ssh2_pkt_addstring(pktout
, signame
);
8322 ssh2_pkt_send(ssh
, pktout
);
8323 logeventf(ssh
, "Sent signal SIG%s", signame
);
8326 /* Never heard of it. Do nothing */
8331 void *new_sock_channel(void *handle
, Socket s
)
8333 Ssh ssh
= (Ssh
) handle
;
8334 struct ssh_channel
*c
;
8335 c
= snew(struct ssh_channel
);
8340 c
->localid
= alloc_channel_id(ssh
);
8342 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
8344 bufchain_init(&c
->v
.v2
.outbuffer
);
8345 add234(ssh
->channels
, c
);
8351 * This is called when stdout/stderr (the entity to which
8352 * from_backend sends data) manages to clear some backlog.
8354 static void ssh_unthrottle(void *handle
, int bufsize
)
8356 Ssh ssh
= (Ssh
) handle
;
8357 if (ssh
->version
== 1) {
8358 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
8359 ssh
->v1_stdout_throttling
= 0;
8360 ssh1_throttle(ssh
, -1);
8363 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
8364 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
8368 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
8370 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
8372 struct Packet
*pktout
;
8374 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
8376 if (ssh
->version
== 1) {
8377 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
8378 PKT_INT
, c
->localid
,
8381 /* PKT_STR, <org:orgport>, */
8384 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
8385 ssh2_pkt_addstring(pktout
, "direct-tcpip");
8386 ssh2_pkt_adduint32(pktout
, c
->localid
);
8387 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
8388 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);/* our window size */
8389 ssh2_pkt_adduint32(pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
8390 ssh2_pkt_addstring(pktout
, hostname
);
8391 ssh2_pkt_adduint32(pktout
, port
);
8393 * We make up values for the originator data; partly it's
8394 * too much hassle to keep track, and partly I'm not
8395 * convinced the server should be told details like that
8396 * about my local network configuration.
8398 ssh2_pkt_addstring(pktout
, "client-side-connection");
8399 ssh2_pkt_adduint32(pktout
, 0);
8400 ssh2_pkt_send(ssh
, pktout
);
8404 static Socket
ssh_socket(void *handle
)
8406 Ssh ssh
= (Ssh
) handle
;
8410 static int ssh_sendok(void *handle
)
8412 Ssh ssh
= (Ssh
) handle
;
8413 return ssh
->send_ok
;
8416 static int ssh_ldisc(void *handle
, int option
)
8418 Ssh ssh
= (Ssh
) handle
;
8419 if (option
== LD_ECHO
)
8420 return ssh
->echoing
;
8421 if (option
== LD_EDIT
)
8422 return ssh
->editing
;
8426 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
8428 Ssh ssh
= (Ssh
) handle
;
8432 static void ssh_provide_logctx(void *handle
, void *logctx
)
8434 Ssh ssh
= (Ssh
) handle
;
8435 ssh
->logctx
= logctx
;
8438 static int ssh_return_exitcode(void *handle
)
8440 Ssh ssh
= (Ssh
) handle
;
8444 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
8448 * cfg_info for SSH is the currently running version of the
8449 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
8451 static int ssh_cfg_info(void *handle
)
8453 Ssh ssh
= (Ssh
) handle
;
8454 return ssh
->version
;
8458 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
8459 * that fails. This variable is the means by which scp.c can reach
8460 * into the SSH code and find out which one it got.
8462 extern int ssh_fallback_cmd(void *handle
)
8464 Ssh ssh
= (Ssh
) handle
;
8465 return ssh
->fallback_cmd
;
8468 Backend ssh_backend
= {
8478 ssh_return_exitcode
,