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
[] = {
467 const static struct ssh_mac
*buggymacs
[] = {
468 &ssh_sha1_buggy
, &ssh_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 */
682 SHA_State exhash
, exhashbase
;
689 unsigned char session_key
[32];
691 int v1_remote_protoflags
;
692 int v1_local_protoflags
;
693 int agentfwd_enabled
;
696 const struct ssh_cipher
*cipher
;
699 const struct ssh2_cipher
*cscipher
, *sccipher
;
700 void *cs_cipher_ctx
, *sc_cipher_ctx
;
701 const struct ssh_mac
*csmac
, *scmac
;
702 void *cs_mac_ctx
, *sc_mac_ctx
;
703 const struct ssh_compress
*cscomp
, *sccomp
;
704 void *cs_comp_ctx
, *sc_comp_ctx
;
705 const struct ssh_kex
*kex
;
706 const struct ssh_signkey
*hostkey
;
707 unsigned char v2_session_id
[20];
713 int echoing
, editing
;
717 int ospeed
, ispeed
; /* temporaries */
718 int term_width
, term_height
;
720 tree234
*channels
; /* indexed by local id */
721 struct ssh_channel
*mainchan
; /* primary session channel */
725 tree234
*rportfwds
, *portfwds
;
729 SSH_STATE_BEFORE_SIZE
,
735 int size_needed
, eof_needed
;
737 struct Packet
**queue
;
738 int queuelen
, queuesize
;
740 unsigned char *deferred_send_data
;
741 int deferred_len
, deferred_size
;
744 * Gross hack: pscp will try to start SFTP but fall back to
745 * scp1 if that fails. This variable is the means by which
746 * scp.c can reach into the SSH code and find out which one it
751 bufchain banner
; /* accumulates banners during do_ssh2_authconn */
753 * Used for username and password input.
755 char *userpass_input_buffer
;
756 int userpass_input_buflen
;
757 int userpass_input_bufpos
;
758 int userpass_input_echo
;
765 int v1_throttle_count
;
768 int v1_stdout_throttling
;
769 unsigned long v2_outgoing_sequence
;
771 int ssh1_rdpkt_crstate
;
772 int ssh2_rdpkt_crstate
;
773 int do_ssh_init_crstate
;
774 int ssh_gotdata_crstate
;
775 int do_ssh1_login_crstate
;
776 int do_ssh1_connection_crstate
;
777 int do_ssh2_transport_crstate
;
778 int do_ssh2_authconn_crstate
;
780 void *do_ssh_init_state
;
781 void *do_ssh1_login_state
;
782 void *do_ssh2_transport_state
;
783 void *do_ssh2_authconn_state
;
785 struct rdpkt1_state_tag rdpkt1_state
;
786 struct rdpkt2_state_tag rdpkt2_state
;
788 /* SSH-1 and SSH-2 use this for different things, but both use it */
789 int protocol_initial_phase_done
;
791 void (*protocol
) (Ssh ssh
, void *vin
, int inlen
,
793 struct Packet
*(*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
796 * We maintain a full _copy_ of a Config structure here, not
797 * merely a pointer to it. That way, when we're passed a new
798 * one for reconfiguration, we can check the differences and
799 * potentially reconfigure port forwardings etc in mid-session.
804 * Used to transfer data back from async callbacks.
806 void *agent_response
;
807 int agent_response_len
;
811 * The SSH connection can be set as `frozen', meaning we are
812 * not currently accepting incoming data from the network. This
813 * is slightly more serious than setting the _socket_ as
814 * frozen, because we may already have had data passed to us
815 * from the network which we need to delay processing until
816 * after the freeze is lifted, so we also need a bufchain to
820 bufchain queued_incoming_data
;
823 * Dispatch table for packet types that we may have to deal
826 handler_fn_t packet_dispatch
[256];
829 * Queues of one-off handler functions for success/failure
830 * indications from a request.
832 struct queued_handler
*qhead
, *qtail
;
835 * This module deals with sending keepalives.
840 * Track incoming and outgoing data sizes and time, for
843 unsigned long incoming_data_size
, outgoing_data_size
, deferred_data_size
;
844 unsigned long max_data_size
;
846 long next_rekey
, last_rekey
;
847 char *deferred_rekey_reason
; /* points to STATIC string; don't free */
850 #define logevent(s) logevent(ssh->frontend, s)
852 /* logevent, only printf-formatted. */
853 static void logeventf(Ssh ssh
, const char *fmt
, ...)
859 buf
= dupvprintf(fmt
, ap
);
865 #define bombout(msg) \
867 char *text = dupprintf msg; \
868 ssh_do_close(ssh, FALSE); \
870 connection_fatal(ssh->frontend, "%s", text); \
874 /* Functions to leave bits out of the SSH packet log file. */
876 static void dont_log_password(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
878 if (ssh
->cfg
.logomitpass
)
879 pkt
->logmode
= blanktype
;
882 static void dont_log_data(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
884 if (ssh
->cfg
.logomitdata
)
885 pkt
->logmode
= blanktype
;
888 static void end_log_omission(Ssh ssh
, struct Packet
*pkt
)
890 pkt
->logmode
= PKTLOG_EMIT
;
893 /* Helper function for common bits of parsing cfg.ttymodes. */
894 static void parse_ttymodes(Ssh ssh
, char *modes
,
895 void (*do_mode
)(void *data
, char *mode
, char *val
),
899 char *t
= strchr(modes
, '\t');
900 char *m
= snewn(t
-modes
+1, char);
902 strncpy(m
, modes
, t
-modes
);
905 val
= get_ttymode(ssh
->frontend
, m
);
909 do_mode(data
, m
, val
);
912 modes
+= strlen(modes
) + 1;
916 static int ssh_channelcmp(void *av
, void *bv
)
918 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
919 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
920 if (a
->localid
< b
->localid
)
922 if (a
->localid
> b
->localid
)
926 static int ssh_channelfind(void *av
, void *bv
)
928 unsigned *a
= (unsigned *) av
;
929 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
937 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
939 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
940 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
942 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
943 return i
< 0 ?
-1 : +1;
944 if (a
->dport
> b
->dport
)
946 if (a
->dport
< b
->dport
)
951 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
953 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
954 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
956 if (a
->sport
> b
->sport
)
958 if (a
->sport
< b
->sport
)
964 * Special form of strcmp which can cope with NULL inputs. NULL is
965 * defined to sort before even the empty string.
967 static int nullstrcmp(const char *a
, const char *b
)
969 if (a
== NULL
&& b
== NULL
)
978 static int ssh_portcmp(void *av
, void *bv
)
980 struct ssh_portfwd
*a
= (struct ssh_portfwd
*) av
;
981 struct ssh_portfwd
*b
= (struct ssh_portfwd
*) bv
;
983 if (a
->type
> b
->type
)
985 if (a
->type
< b
->type
)
987 if (a
->addressfamily
> b
->addressfamily
)
989 if (a
->addressfamily
< b
->addressfamily
)
991 if ( (i
= nullstrcmp(a
->saddr
, b
->saddr
)) != 0)
992 return i
< 0 ?
-1 : +1;
993 if (a
->sport
> b
->sport
)
995 if (a
->sport
< b
->sport
)
997 if (a
->type
!= 'D') {
998 if ( (i
= nullstrcmp(a
->daddr
, b
->daddr
)) != 0)
999 return i
< 0 ?
-1 : +1;
1000 if (a
->dport
> b
->dport
)
1002 if (a
->dport
< b
->dport
)
1008 static int alloc_channel_id(Ssh ssh
)
1010 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
1011 unsigned low
, high
, mid
;
1013 struct ssh_channel
*c
;
1016 * First-fit allocation of channel numbers: always pick the
1017 * lowest unused one. To do this, binary-search using the
1018 * counted B-tree to find the largest channel ID which is in a
1019 * contiguous sequence from the beginning. (Precisely
1020 * everything in that sequence must have ID equal to its tree
1021 * index plus CHANNEL_NUMBER_OFFSET.)
1023 tsize
= count234(ssh
->channels
);
1027 while (high
- low
> 1) {
1028 mid
= (high
+ low
) / 2;
1029 c
= index234(ssh
->channels
, mid
);
1030 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
1031 low
= mid
; /* this one is fine */
1033 high
= mid
; /* this one is past it */
1036 * Now low points to either -1, or the tree index of the
1037 * largest ID in the initial sequence.
1040 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
1041 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
1043 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
1046 static void c_write(Ssh ssh
, const char *buf
, int len
)
1048 if ((flags
& FLAG_STDERR
)) {
1050 for (i
= 0; i
< len
; i
++)
1052 fputc(buf
[i
], stderr
);
1055 from_backend(ssh
->frontend
, 1, buf
, len
);
1058 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
1061 for (i
= 0; i
< len
; i
++) {
1063 c_write(ssh
, "\r\n", 2);
1064 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
1065 c_write(ssh
, buf
+ i
, 1);
1069 static void c_write_str(Ssh ssh
, const char *buf
)
1071 c_write(ssh
, buf
, strlen(buf
));
1074 static void ssh_free_packet(struct Packet
*pkt
)
1079 static struct Packet
*ssh_new_packet(void)
1081 struct Packet
*pkt
= snew(struct Packet
);
1083 pkt
->body
= pkt
->data
= NULL
;
1085 pkt
->logmode
= PKTLOG_EMIT
;
1093 * Collect incoming data in the incoming packet buffer.
1094 * Decipher and verify the packet when it is completely read.
1095 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
1096 * Update the *data and *datalen variables.
1097 * Return a Packet structure when a packet is completed.
1099 static struct Packet
*ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1101 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
1103 crBegin(ssh
->ssh1_rdpkt_crstate
);
1105 st
->pktin
= ssh_new_packet();
1107 st
->pktin
->type
= 0;
1108 st
->pktin
->length
= 0;
1110 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
1111 while ((*datalen
) == 0)
1113 st
->len
= (st
->len
<< 8) + **data
;
1114 (*data
)++, (*datalen
)--;
1117 st
->pad
= 8 - (st
->len
% 8);
1118 st
->biglen
= st
->len
+ st
->pad
;
1119 st
->pktin
->length
= st
->len
- 5;
1121 if (st
->biglen
< 0) {
1122 bombout(("Extremely large packet length from server suggests"
1123 " data stream corruption"));
1124 ssh_free_packet(st
->pktin
);
1128 st
->pktin
->maxlen
= st
->biglen
;
1129 st
->pktin
->data
= snewn(st
->biglen
+ APIEXTRA
, unsigned char);
1131 st
->to_read
= st
->biglen
;
1132 st
->p
= st
->pktin
->data
;
1133 while (st
->to_read
> 0) {
1134 st
->chunk
= st
->to_read
;
1135 while ((*datalen
) == 0)
1137 if (st
->chunk
> (*datalen
))
1138 st
->chunk
= (*datalen
);
1139 memcpy(st
->p
, *data
, st
->chunk
);
1141 *datalen
-= st
->chunk
;
1143 st
->to_read
-= st
->chunk
;
1146 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, st
->pktin
->data
,
1147 st
->biglen
, NULL
)) {
1148 bombout(("Network attack (CRC compensation) detected!"));
1149 ssh_free_packet(st
->pktin
);
1154 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, st
->pktin
->data
, st
->biglen
);
1156 st
->realcrc
= crc32_compute(st
->pktin
->data
, st
->biglen
- 4);
1157 st
->gotcrc
= GET_32BIT(st
->pktin
->data
+ st
->biglen
- 4);
1158 if (st
->gotcrc
!= st
->realcrc
) {
1159 bombout(("Incorrect CRC received on packet"));
1160 ssh_free_packet(st
->pktin
);
1164 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1165 st
->pktin
->savedpos
= 0;
1167 if (ssh
->v1_compressing
) {
1168 unsigned char *decompblk
;
1170 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
1171 st
->pktin
->body
- 1, st
->pktin
->length
+ 1,
1172 &decompblk
, &decomplen
)) {
1173 bombout(("Zlib decompression encountered invalid data"));
1174 ssh_free_packet(st
->pktin
);
1178 if (st
->pktin
->maxlen
< st
->pad
+ decomplen
) {
1179 st
->pktin
->maxlen
= st
->pad
+ decomplen
;
1180 st
->pktin
->data
= sresize(st
->pktin
->data
,
1181 st
->pktin
->maxlen
+ APIEXTRA
,
1183 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1186 memcpy(st
->pktin
->body
- 1, decompblk
, decomplen
);
1188 st
->pktin
->length
= decomplen
- 1;
1191 st
->pktin
->type
= st
->pktin
->body
[-1];
1194 * Log incoming packet, possibly omitting sensitive fields.
1198 struct logblank_t blank
;
1199 if (ssh
->cfg
.logomitdata
) {
1200 int do_blank
= FALSE
, blank_prefix
= 0;
1201 /* "Session data" packets - omit the data field */
1202 if ((st
->pktin
->type
== SSH1_SMSG_STDOUT_DATA
) ||
1203 (st
->pktin
->type
== SSH1_SMSG_STDERR_DATA
)) {
1204 do_blank
= TRUE
; blank_prefix
= 0;
1205 } else if (st
->pktin
->type
== SSH1_MSG_CHANNEL_DATA
) {
1206 do_blank
= TRUE
; blank_prefix
= 4;
1209 blank
.offset
= blank_prefix
;
1210 blank
.len
= st
->pktin
->length
;
1211 blank
.type
= PKTLOG_OMIT
;
1215 log_packet(ssh
->logctx
,
1216 PKT_INCOMING
, st
->pktin
->type
,
1217 ssh1_pkt_type(st
->pktin
->type
),
1218 st
->pktin
->body
, st
->pktin
->length
,
1222 crFinish(st
->pktin
);
1225 static struct Packet
*ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1227 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1229 crBegin(ssh
->ssh2_rdpkt_crstate
);
1231 st
->pktin
= ssh_new_packet();
1233 st
->pktin
->type
= 0;
1234 st
->pktin
->length
= 0;
1236 st
->cipherblk
= ssh
->sccipher
->blksize
;
1239 if (st
->cipherblk
< 8)
1242 st
->pktin
->data
= snewn(st
->cipherblk
+ APIEXTRA
, unsigned char);
1245 * Acquire and decrypt the first block of the packet. This will
1246 * contain the length and padding details.
1248 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1249 while ((*datalen
) == 0)
1251 st
->pktin
->data
[st
->i
] = *(*data
)++;
1256 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1257 st
->pktin
->data
, st
->cipherblk
);
1260 * Now get the length and padding figures.
1262 st
->len
= GET_32BIT(st
->pktin
->data
);
1263 st
->pad
= st
->pktin
->data
[4];
1266 * _Completely_ silly lengths should be stomped on before they
1267 * do us any more damage.
1269 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
1270 bombout(("Incoming packet was garbled on decryption"));
1271 ssh_free_packet(st
->pktin
);
1276 * This enables us to deduce the payload length.
1278 st
->payload
= st
->len
- st
->pad
- 1;
1280 st
->pktin
->length
= st
->payload
+ 5;
1283 * So now we can work out the total packet length.
1285 st
->packetlen
= st
->len
+ 4;
1286 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1289 * Allocate memory for the rest of the packet.
1291 st
->pktin
->maxlen
= st
->packetlen
+ st
->maclen
;
1292 st
->pktin
->data
= sresize(st
->pktin
->data
,
1293 st
->pktin
->maxlen
+ APIEXTRA
,
1297 * Read and decrypt the remainder of the packet.
1299 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1301 while ((*datalen
) == 0)
1303 st
->pktin
->data
[st
->i
] = *(*data
)++;
1306 /* Decrypt everything _except_ the MAC. */
1308 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1309 st
->pktin
->data
+ st
->cipherblk
,
1310 st
->packetlen
- st
->cipherblk
);
1312 st
->pktin
->encrypted_len
= st
->packetlen
;
1318 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, st
->pktin
->data
, st
->len
+ 4,
1319 st
->incoming_sequence
)) {
1320 bombout(("Incorrect MAC received on packet"));
1321 ssh_free_packet(st
->pktin
);
1325 st
->pktin
->sequence
= st
->incoming_sequence
++;
1328 * Decompress packet payload.
1331 unsigned char *newpayload
;
1334 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1335 st
->pktin
->data
+ 5, st
->pktin
->length
- 5,
1336 &newpayload
, &newlen
)) {
1337 if (st
->pktin
->maxlen
< newlen
+ 5) {
1338 st
->pktin
->maxlen
= newlen
+ 5;
1339 st
->pktin
->data
= sresize(st
->pktin
->data
,
1340 st
->pktin
->maxlen
+ APIEXTRA
,
1343 st
->pktin
->length
= 5 + newlen
;
1344 memcpy(st
->pktin
->data
+ 5, newpayload
, newlen
);
1349 st
->pktin
->savedpos
= 6;
1350 st
->pktin
->body
= st
->pktin
->data
;
1351 st
->pktin
->type
= st
->pktin
->data
[5];
1354 * Log incoming packet, possibly omitting sensitive fields.
1358 struct logblank_t blank
;
1359 if (ssh
->cfg
.logomitdata
) {
1360 int do_blank
= FALSE
, blank_prefix
= 0;
1361 /* "Session data" packets - omit the data field */
1362 if (st
->pktin
->type
== SSH2_MSG_CHANNEL_DATA
) {
1363 do_blank
= TRUE
; blank_prefix
= 4;
1364 } else if (st
->pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1365 do_blank
= TRUE
; blank_prefix
= 8;
1368 blank
.offset
= blank_prefix
;
1369 blank
.len
= (st
->pktin
->length
-6) - blank_prefix
;
1370 blank
.type
= PKTLOG_OMIT
;
1374 log_packet(ssh
->logctx
, PKT_INCOMING
, st
->pktin
->type
,
1375 ssh2_pkt_type(ssh
->pkt_ctx
, st
->pktin
->type
),
1376 st
->pktin
->data
+6, st
->pktin
->length
-6,
1380 crFinish(st
->pktin
);
1383 static int s_wrpkt_prepare(Ssh ssh
, struct Packet
*pkt
, int *offset_p
)
1385 int pad
, biglen
, i
, pktoffs
;
1389 * XXX various versions of SC (including 8.8.4) screw up the
1390 * register allocation in this function and use the same register
1391 * (D6) for len and as a temporary, with predictable results. The
1392 * following sledgehammer prevents this.
1399 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[12],
1400 ssh1_pkt_type(pkt
->data
[12]),
1401 pkt
->body
, pkt
->length
- (pkt
->body
- pkt
->data
),
1402 pkt
->nblanks
, pkt
->blanks
);
1403 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1406 if (ssh
->v1_compressing
) {
1407 unsigned char *compblk
;
1409 zlib_compress_block(ssh
->cs_comp_ctx
,
1410 pkt
->data
+ 12, pkt
->length
- 12,
1411 &compblk
, &complen
);
1412 memcpy(pkt
->data
+ 12, compblk
, complen
);
1414 pkt
->length
= complen
+ 12;
1417 ssh_pkt_ensure(pkt
, pkt
->length
+ 4); /* space for CRC */
1419 len
= pkt
->length
- 4 - 8; /* len(type+data+CRC) */
1420 pad
= 8 - (len
% 8);
1422 biglen
= len
+ pad
; /* len(padding+type+data+CRC) */
1424 for (i
= pktoffs
; i
< 4+8; i
++)
1425 pkt
->data
[i
] = random_byte();
1426 crc
= crc32_compute(pkt
->data
+ pktoffs
+ 4, biglen
- 4); /* all ex len */
1427 PUT_32BIT(pkt
->data
+ pktoffs
+ 4 + biglen
- 4, crc
);
1428 PUT_32BIT(pkt
->data
+ pktoffs
, len
);
1431 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
,
1432 pkt
->data
+ pktoffs
+ 4, biglen
);
1434 if (offset_p
) *offset_p
= pktoffs
;
1435 return biglen
+ 4; /* len(length+padding+type+data+CRC) */
1438 static void s_wrpkt(Ssh ssh
, struct Packet
*pkt
)
1440 int len
, backlog
, offset
;
1441 len
= s_wrpkt_prepare(ssh
, pkt
, &offset
);
1442 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
+ offset
, len
);
1443 if (backlog
> SSH_MAX_BACKLOG
)
1444 ssh_throttle_all(ssh
, 1, backlog
);
1445 ssh_free_packet(pkt
);
1448 static void s_wrpkt_defer(Ssh ssh
, struct Packet
*pkt
)
1451 len
= s_wrpkt_prepare(ssh
, pkt
, &offset
);
1452 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1453 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1454 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1458 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
,
1459 pkt
->data
+ offset
, len
);
1460 ssh
->deferred_len
+= len
;
1461 ssh_free_packet(pkt
);
1465 * Construct a SSH-1 packet with the specified contents.
1466 * (This all-at-once interface used to be the only one, but now SSH-1
1467 * packets can also be constructed incrementally.)
1469 static struct Packet
*construct_packet(Ssh ssh
, int pkttype
, va_list ap
)
1475 pkt
= ssh1_pkt_init(pkttype
);
1477 while ((argtype
= va_arg(ap
, int)) != PKT_END
) {
1478 unsigned char *argp
, argchar
;
1479 unsigned long argint
;
1482 /* Actual fields in the packet */
1484 argint
= va_arg(ap
, int);
1485 ssh_pkt_adduint32(pkt
, argint
);
1488 argchar
= (unsigned char) va_arg(ap
, int);
1489 ssh_pkt_addbyte(pkt
, argchar
);
1492 argp
= va_arg(ap
, unsigned char *);
1493 arglen
= va_arg(ap
, int);
1494 ssh_pkt_adddata(pkt
, argp
, arglen
);
1497 argp
= va_arg(ap
, unsigned char *);
1498 ssh_pkt_addstring(pkt
, argp
);
1501 bn
= va_arg(ap
, Bignum
);
1502 ssh1_pkt_addmp(pkt
, bn
);
1504 /* Tokens for modifications to packet logging */
1506 dont_log_password(ssh
, pkt
, PKTLOG_BLANK
);
1509 dont_log_data(ssh
, pkt
, PKTLOG_OMIT
);
1512 end_log_omission(ssh
, pkt
);
1520 static void send_packet(Ssh ssh
, int pkttype
, ...)
1524 va_start(ap
, pkttype
);
1525 pkt
= construct_packet(ssh
, pkttype
, ap
);
1530 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1534 va_start(ap
, pkttype
);
1535 pkt
= construct_packet(ssh
, pkttype
, ap
);
1537 s_wrpkt_defer(ssh
, pkt
);
1540 static int ssh_versioncmp(char *a
, char *b
)
1543 unsigned long av
, bv
;
1545 av
= strtoul(a
, &ae
, 10);
1546 bv
= strtoul(b
, &be
, 10);
1548 return (av
< bv ?
-1 : +1);
1553 av
= strtoul(ae
, &ae
, 10);
1554 bv
= strtoul(be
, &be
, 10);
1556 return (av
< bv ?
-1 : +1);
1561 * Utility routines for putting an SSH-protocol `string' and
1562 * `uint32' into a SHA state.
1564 static void sha_string(SHA_State
* s
, void *str
, int len
)
1566 unsigned char lenblk
[4];
1567 PUT_32BIT(lenblk
, len
);
1568 SHA_Bytes(s
, lenblk
, 4);
1569 SHA_Bytes(s
, str
, len
);
1572 static void sha_uint32(SHA_State
* s
, unsigned i
)
1574 unsigned char intblk
[4];
1575 PUT_32BIT(intblk
, i
);
1576 SHA_Bytes(s
, intblk
, 4);
1580 * Packet construction functions. Mostly shared between SSH-1 and SSH-2.
1582 static void ssh_pkt_ensure(struct Packet
*pkt
, int length
)
1584 if (pkt
->maxlen
< length
) {
1585 unsigned char *body
= pkt
->body
;
1586 int offset
= body ? pkt
->data
- body
: 0;
1587 pkt
->maxlen
= length
+ 256;
1588 pkt
->data
= sresize(pkt
->data
, pkt
->maxlen
+ APIEXTRA
, unsigned char);
1589 if (body
) pkt
->body
= pkt
->data
+ offset
;
1592 static void ssh_pkt_adddata(struct Packet
*pkt
, void *data
, int len
)
1594 if (pkt
->logmode
!= PKTLOG_EMIT
) {
1596 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
, struct logblank_t
);
1598 pkt
->blanks
[pkt
->nblanks
-1].offset
= pkt
->length
-
1599 (pkt
->body
- pkt
->data
);
1600 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1601 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1604 ssh_pkt_ensure(pkt
, pkt
->length
);
1605 memcpy(pkt
->data
+ pkt
->length
- len
, data
, len
);
1607 static void ssh_pkt_addbyte(struct Packet
*pkt
, unsigned char byte
)
1609 ssh_pkt_adddata(pkt
, &byte
, 1);
1611 static void ssh2_pkt_addbool(struct Packet
*pkt
, unsigned char value
)
1613 ssh_pkt_adddata(pkt
, &value
, 1);
1615 static void ssh_pkt_adduint32(struct Packet
*pkt
, unsigned long value
)
1618 PUT_32BIT(x
, value
);
1619 ssh_pkt_adddata(pkt
, x
, 4);
1621 static void ssh_pkt_addstring_start(struct Packet
*pkt
)
1623 ssh_pkt_adduint32(pkt
, 0);
1624 pkt
->savedpos
= pkt
->length
;
1626 static void ssh_pkt_addstring_str(struct Packet
*pkt
, char *data
)
1628 ssh_pkt_adddata(pkt
, data
, strlen(data
));
1629 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1631 static void ssh_pkt_addstring_data(struct Packet
*pkt
, char *data
, int len
)
1633 ssh_pkt_adddata(pkt
, data
, len
);
1634 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1636 static void ssh_pkt_addstring(struct Packet
*pkt
, char *data
)
1638 ssh_pkt_addstring_start(pkt
);
1639 ssh_pkt_addstring_str(pkt
, data
);
1641 static void ssh1_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1643 int len
= ssh1_bignum_length(b
);
1644 unsigned char *data
= snewn(len
, char);
1645 (void) ssh1_write_bignum(data
, b
);
1646 ssh_pkt_adddata(pkt
, data
, len
);
1649 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1652 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1653 p
= snewn(n
+ 1, unsigned char);
1655 fatalbox("out of memory");
1657 for (i
= 1; i
<= n
; i
++)
1658 p
[i
] = bignum_byte(b
, n
- i
);
1660 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1662 memmove(p
, p
+ i
, n
+ 1 - i
);
1666 static void ssh2_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1670 p
= ssh2_mpint_fmt(b
, &len
);
1671 ssh_pkt_addstring_start(pkt
);
1672 ssh_pkt_addstring_data(pkt
, (char *)p
, len
);
1676 static struct Packet
*ssh1_pkt_init(int pkt_type
)
1678 struct Packet
*pkt
= ssh_new_packet();
1679 pkt
->length
= 4 + 8; /* space for length + max padding */
1680 ssh_pkt_addbyte(pkt
, pkt_type
);
1681 pkt
->body
= pkt
->data
+ pkt
->length
;
1685 /* For legacy code (SSH-1 and -2 packet construction used to be separate) */
1686 #define ssh2_pkt_ensure(pkt, length) ssh_pkt_ensure(pkt, length)
1687 #define ssh2_pkt_adddata(pkt, data, len) ssh_pkt_adddata(pkt, data, len)
1688 #define ssh2_pkt_addbyte(pkt, byte) ssh_pkt_addbyte(pkt, byte)
1689 #define ssh2_pkt_adduint32(pkt, value) ssh_pkt_adduint32(pkt, value)
1690 #define ssh2_pkt_addstring_start(pkt) ssh_pkt_addstring_start(pkt)
1691 #define ssh2_pkt_addstring_str(pkt, data) ssh_pkt_addstring_str(pkt, data)
1692 #define ssh2_pkt_addstring_data(pkt, data, len) ssh_pkt_addstring_data(pkt, data, len)
1693 #define ssh2_pkt_addstring(pkt, data) ssh_pkt_addstring(pkt, data)
1695 static struct Packet
*ssh2_pkt_init(int pkt_type
)
1697 struct Packet
*pkt
= ssh_new_packet();
1700 ssh_pkt_addbyte(pkt
, (unsigned char) pkt_type
);
1701 pkt
->body
= pkt
->data
+ pkt
->length
;
1706 * Construct an SSH-2 final-form packet: compress it, encrypt it,
1707 * put the MAC on it. Final packet, ready to be sent, is stored in
1708 * pkt->data. Total length is returned.
1710 static int ssh2_pkt_construct(Ssh ssh
, struct Packet
*pkt
)
1712 int cipherblk
, maclen
, padding
, i
;
1715 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[5],
1716 ssh2_pkt_type(ssh
->pkt_ctx
, pkt
->data
[5]),
1717 pkt
->body
, pkt
->length
- (pkt
->body
- pkt
->data
),
1718 pkt
->nblanks
, pkt
->blanks
);
1719 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1723 * Compress packet payload.
1726 unsigned char *newpayload
;
1729 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, pkt
->data
+ 5,
1731 &newpayload
, &newlen
)) {
1733 ssh2_pkt_adddata(pkt
, newpayload
, newlen
);
1739 * Add padding. At least four bytes, and must also bring total
1740 * length (minus MAC) up to a multiple of the block size.
1741 * If pkt->forcepad is set, make sure the packet is at least that size
1744 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1745 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1747 if (pkt
->length
+ padding
< pkt
->forcepad
)
1748 padding
= pkt
->forcepad
- pkt
->length
;
1750 (cipherblk
- (pkt
->length
+ padding
) % cipherblk
) % cipherblk
;
1751 assert(padding
<= 255);
1752 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1753 ssh2_pkt_ensure(pkt
, pkt
->length
+ padding
+ maclen
);
1754 pkt
->data
[4] = padding
;
1755 for (i
= 0; i
< padding
; i
++)
1756 pkt
->data
[pkt
->length
+ i
] = random_byte();
1757 PUT_32BIT(pkt
->data
, pkt
->length
+ padding
- 4);
1759 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, pkt
->data
,
1760 pkt
->length
+ padding
,
1761 ssh
->v2_outgoing_sequence
);
1762 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1765 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1766 pkt
->data
, pkt
->length
+ padding
);
1768 pkt
->encrypted_len
= pkt
->length
+ padding
;
1770 /* Ready-to-send packet starts at pkt->data. We return length. */
1771 return pkt
->length
+ padding
+ maclen
;
1775 * Routines called from the main SSH code to send packets. There
1776 * are quite a few of these, because we have two separate
1777 * mechanisms for delaying the sending of packets:
1779 * - In order to send an IGNORE message and a password message in
1780 * a single fixed-length blob, we require the ability to
1781 * concatenate the encrypted forms of those two packets _into_ a
1782 * single blob and then pass it to our <network.h> transport
1783 * layer in one go. Hence, there's a deferment mechanism which
1784 * works after packet encryption.
1786 * - In order to avoid sending any connection-layer messages
1787 * during repeat key exchange, we have to queue up any such
1788 * outgoing messages _before_ they are encrypted (and in
1789 * particular before they're allocated sequence numbers), and
1790 * then send them once we've finished.
1792 * I call these mechanisms `defer' and `queue' respectively, so as
1793 * to distinguish them reasonably easily.
1795 * The functions send_noqueue() and defer_noqueue() free the packet
1796 * structure they are passed. Every outgoing packet goes through
1797 * precisely one of these functions in its life; packets passed to
1798 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1799 * these or get queued, and then when the queue is later emptied
1800 * the packets are all passed to defer_noqueue().
1802 * When using a CBC-mode cipher, it's necessary to ensure that an
1803 * attacker can't provide data to be encrypted using an IV that they
1804 * know. We ensure this by prefixing each packet that might contain
1805 * user data with an SSH_MSG_IGNORE. This is done using the deferral
1806 * mechanism, so in this case send_noqueue() ends up redirecting to
1807 * defer_noqueue(). If you don't like this inefficiency, don't use
1811 static void ssh2_pkt_defer_noqueue(Ssh
, struct Packet
*, int);
1812 static void ssh_pkt_defersend(Ssh
);
1815 * Send an SSH-2 packet immediately, without queuing or deferring.
1817 static void ssh2_pkt_send_noqueue(Ssh ssh
, struct Packet
*pkt
)
1821 if (ssh
->cscipher
!= NULL
&& (ssh
->cscipher
->flags
& SSH_CIPHER_IS_CBC
)) {
1822 /* We need to send two packets, so use the deferral mechanism. */
1823 ssh2_pkt_defer_noqueue(ssh
, pkt
, FALSE
);
1824 ssh_pkt_defersend(ssh
);
1827 len
= ssh2_pkt_construct(ssh
, pkt
);
1828 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1829 if (backlog
> SSH_MAX_BACKLOG
)
1830 ssh_throttle_all(ssh
, 1, backlog
);
1832 ssh
->outgoing_data_size
+= pkt
->encrypted_len
;
1833 if (!ssh
->kex_in_progress
&&
1834 ssh
->max_data_size
!= 0 &&
1835 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1836 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1838 ssh_free_packet(pkt
);
1842 * Defer an SSH-2 packet.
1844 static void ssh2_pkt_defer_noqueue(Ssh ssh
, struct Packet
*pkt
, int noignore
)
1847 if (ssh
->cscipher
!= NULL
&& (ssh
->cscipher
->flags
& SSH_CIPHER_IS_CBC
) &&
1848 ssh
->deferred_len
== 0 && !noignore
) {
1850 * Interpose an SSH_MSG_IGNORE to ensure that user data don't
1851 * get encrypted with a known IV.
1853 struct Packet
*ipkt
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
1854 ssh2_pkt_defer_noqueue(ssh
, ipkt
, TRUE
);
1856 len
= ssh2_pkt_construct(ssh
, pkt
);
1857 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1858 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1859 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1863 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1864 ssh
->deferred_len
+= len
;
1865 ssh
->deferred_data_size
+= pkt
->encrypted_len
;
1866 ssh_free_packet(pkt
);
1870 * Queue an SSH-2 packet.
1872 static void ssh2_pkt_queue(Ssh ssh
, struct Packet
*pkt
)
1874 assert(ssh
->queueing
);
1876 if (ssh
->queuelen
>= ssh
->queuesize
) {
1877 ssh
->queuesize
= ssh
->queuelen
+ 32;
1878 ssh
->queue
= sresize(ssh
->queue
, ssh
->queuesize
, struct Packet
*);
1881 ssh
->queue
[ssh
->queuelen
++] = pkt
;
1885 * Either queue or send a packet, depending on whether queueing is
1888 static void ssh2_pkt_send(Ssh ssh
, struct Packet
*pkt
)
1891 ssh2_pkt_queue(ssh
, pkt
);
1893 ssh2_pkt_send_noqueue(ssh
, pkt
);
1898 * Either queue or defer a packet, depending on whether queueing is
1901 static void ssh2_pkt_defer(Ssh ssh
, struct Packet
*pkt
)
1904 ssh2_pkt_queue(ssh
, pkt
);
1906 ssh2_pkt_defer_noqueue(ssh
, pkt
, FALSE
);
1911 * Send the whole deferred data block constructed by
1912 * ssh2_pkt_defer() or SSH-1's defer_packet().
1914 * The expected use of the defer mechanism is that you call
1915 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1916 * not currently queueing, this simply sets up deferred_send_data
1917 * and then sends it. If we _are_ currently queueing, the calls to
1918 * ssh2_pkt_defer() put the deferred packets on to the queue
1919 * instead, and therefore ssh_pkt_defersend() has no deferred data
1920 * to send. Hence, there's no need to make it conditional on
1923 static void ssh_pkt_defersend(Ssh ssh
)
1926 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1928 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1929 sfree(ssh
->deferred_send_data
);
1930 ssh
->deferred_send_data
= NULL
;
1931 if (backlog
> SSH_MAX_BACKLOG
)
1932 ssh_throttle_all(ssh
, 1, backlog
);
1934 ssh
->outgoing_data_size
+= ssh
->deferred_data_size
;
1935 if (!ssh
->kex_in_progress
&&
1936 ssh
->max_data_size
!= 0 &&
1937 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1938 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1939 ssh
->deferred_data_size
= 0;
1943 * Send all queued SSH-2 packets. We send them by means of
1944 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1945 * packets that needed to be lumped together.
1947 static void ssh2_pkt_queuesend(Ssh ssh
)
1951 assert(!ssh
->queueing
);
1953 for (i
= 0; i
< ssh
->queuelen
; i
++)
1954 ssh2_pkt_defer_noqueue(ssh
, ssh
->queue
[i
], FALSE
);
1957 ssh_pkt_defersend(ssh
);
1961 void bndebug(char *string
, Bignum b
)
1965 p
= ssh2_mpint_fmt(b
, &len
);
1966 debug(("%s", string
));
1967 for (i
= 0; i
< len
; i
++)
1968 debug((" %02x", p
[i
]));
1974 static void sha_mpint(SHA_State
* s
, Bignum b
)
1978 p
= ssh2_mpint_fmt(b
, &len
);
1979 sha_string(s
, p
, len
);
1984 * Packet decode functions for both SSH-1 and SSH-2.
1986 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
)
1988 unsigned long value
;
1989 if (pkt
->length
- pkt
->savedpos
< 4)
1990 return 0; /* arrgh, no way to decline (FIXME?) */
1991 value
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1995 static int ssh2_pkt_getbool(struct Packet
*pkt
)
1997 unsigned long value
;
1998 if (pkt
->length
- pkt
->savedpos
< 1)
1999 return 0; /* arrgh, no way to decline (FIXME?) */
2000 value
= pkt
->body
[pkt
->savedpos
] != 0;
2004 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
)
2009 if (pkt
->length
- pkt
->savedpos
< 4)
2011 len
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
2016 if (pkt
->length
- pkt
->savedpos
< *length
)
2018 *p
= (char *)(pkt
->body
+ pkt
->savedpos
);
2019 pkt
->savedpos
+= *length
;
2021 static void *ssh_pkt_getdata(struct Packet
*pkt
, int length
)
2023 if (pkt
->length
- pkt
->savedpos
< length
)
2025 pkt
->savedpos
+= length
;
2026 return pkt
->body
+ (pkt
->savedpos
- length
);
2028 static int ssh1_pkt_getrsakey(struct Packet
*pkt
, struct RSAKey
*key
,
2029 unsigned char **keystr
)
2033 j
= makekey(pkt
->body
+ pkt
->savedpos
,
2034 pkt
->length
- pkt
->savedpos
,
2041 assert(pkt
->savedpos
< pkt
->length
);
2045 static Bignum
ssh1_pkt_getmp(struct Packet
*pkt
)
2050 j
= ssh1_read_bignum(pkt
->body
+ pkt
->savedpos
,
2051 pkt
->length
- pkt
->savedpos
, &b
);
2059 static Bignum
ssh2_pkt_getmp(struct Packet
*pkt
)
2065 ssh_pkt_getstring(pkt
, &p
, &length
);
2070 b
= bignum_from_bytes((unsigned char *)p
, length
);
2075 * Helper function to add an SSH-2 signature blob to a packet.
2076 * Expects to be shown the public key blob as well as the signature
2077 * blob. Normally works just like ssh2_pkt_addstring, but will
2078 * fiddle with the signature packet if necessary for
2079 * BUG_SSH2_RSA_PADDING.
2081 static void ssh2_add_sigblob(Ssh ssh
, struct Packet
*pkt
,
2082 void *pkblob_v
, int pkblob_len
,
2083 void *sigblob_v
, int sigblob_len
)
2085 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
2086 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
2088 /* dmemdump(pkblob, pkblob_len); */
2089 /* dmemdump(sigblob, sigblob_len); */
2092 * See if this is in fact an ssh-rsa signature and a buggy
2093 * server; otherwise we can just do this the easy way.
2095 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
2096 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
2097 int pos
, len
, siglen
;
2100 * Find the byte length of the modulus.
2103 pos
= 4+7; /* skip over "ssh-rsa" */
2104 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
2105 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
2106 pos
+= 4; /* find modulus itself */
2107 while (len
> 0 && pkblob
[pos
] == 0)
2109 /* debug(("modulus length is %d\n", len)); */
2112 * Now find the signature integer.
2114 pos
= 4+7; /* skip over "ssh-rsa" */
2115 siglen
= GET_32BIT(sigblob
+pos
);
2116 /* debug(("signature length is %d\n", siglen)); */
2118 if (len
!= siglen
) {
2119 unsigned char newlen
[4];
2120 ssh2_pkt_addstring_start(pkt
);
2121 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, pos
);
2122 /* dmemdump(sigblob, pos); */
2123 pos
+= 4; /* point to start of actual sig */
2124 PUT_32BIT(newlen
, len
);
2125 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 4);
2126 /* dmemdump(newlen, 4); */
2128 while (len
-- > siglen
) {
2129 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 1);
2130 /* dmemdump(newlen, 1); */
2132 ssh2_pkt_addstring_data(pkt
, (char *)(sigblob
+pos
), siglen
);
2133 /* dmemdump(sigblob+pos, siglen); */
2137 /* Otherwise fall through and do it the easy way. */
2140 ssh2_pkt_addstring_start(pkt
);
2141 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, sigblob_len
);
2145 * Examine the remote side's version string and compare it against
2146 * a list of known buggy implementations.
2148 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
2150 char *imp
; /* pointer to implementation part */
2152 imp
+= strcspn(imp
, "-");
2154 imp
+= strcspn(imp
, "-");
2157 ssh
->remote_bugs
= 0;
2159 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
2160 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
2161 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
2162 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
2163 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
2164 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
2166 * These versions don't support SSH1_MSG_IGNORE, so we have
2167 * to use a different defence against password length
2170 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
2171 logevent("We believe remote version has SSH-1 ignore bug");
2174 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
2175 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
2176 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
2178 * These versions need a plain password sent; they can't
2179 * handle having a null and a random length of data after
2182 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
2183 logevent("We believe remote version needs a plain SSH-1 password");
2186 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
2187 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
2188 (!strcmp(imp
, "Cisco-1.25")))) {
2190 * These versions apparently have no clue whatever about
2191 * RSA authentication and will panic and die if they see
2192 * an AUTH_RSA message.
2194 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
2195 logevent("We believe remote version can't handle SSH-1 RSA authentication");
2198 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
2199 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
2200 !wc_match("* VShell", imp
) &&
2201 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
2202 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
2203 wc_match("2.1 *", imp
)))) {
2205 * These versions have the HMAC bug.
2207 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
2208 logevent("We believe remote version has SSH-2 HMAC bug");
2211 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2212 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2213 !wc_match("* VShell", imp
) &&
2214 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2216 * These versions have the key-derivation bug (failing to
2217 * include the literal shared secret in the hashes that
2218 * generate the keys).
2220 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2221 logevent("We believe remote version has SSH-2 key-derivation bug");
2224 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2225 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2226 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2227 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2229 * These versions have the SSH-2 RSA padding bug.
2231 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2232 logevent("We believe remote version has SSH-2 RSA padding bug");
2235 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2236 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2237 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2239 * These versions have the SSH-2 session-ID bug in
2240 * public-key authentication.
2242 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2243 logevent("We believe remote version has SSH-2 public-key-session-ID bug");
2246 if (ssh
->cfg
.sshbug_rekey2
== FORCE_ON
||
2247 (ssh
->cfg
.sshbug_rekey2
== AUTO
&&
2248 (wc_match("OpenSSH_2.[0-4]*", imp
) ||
2249 wc_match("OpenSSH_2.5.[0-3]*", imp
) ||
2250 wc_match("Sun_SSH_1.0", imp
) ||
2251 wc_match("Sun_SSH_1.0.1", imp
)))) {
2253 * These versions have the SSH-2 rekey bug.
2255 ssh
->remote_bugs
|= BUG_SSH2_REKEY
;
2256 logevent("We believe remote version has SSH-2 rekey bug");
2261 * The `software version' part of an SSH version string is required
2262 * to contain no spaces or minus signs.
2264 static void ssh_fix_verstring(char *str
)
2266 /* Eat "SSH-<protoversion>-". */
2267 assert(*str
== 'S'); str
++;
2268 assert(*str
== 'S'); str
++;
2269 assert(*str
== 'H'); str
++;
2270 assert(*str
== '-'); str
++;
2271 while (*str
&& *str
!= '-') str
++;
2272 assert(*str
== '-'); str
++;
2274 /* Convert minus signs and spaces in the remaining string into
2277 if (*str
== '-' || *str
== ' ')
2283 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2285 struct do_ssh_init_state
{
2293 crState(do_ssh_init_state
);
2295 crBegin(ssh
->do_ssh_init_crstate
);
2297 /* Search for the string "SSH-" in the input. */
2300 static const int transS
[] = { 1, 2, 2, 1 };
2301 static const int transH
[] = { 0, 0, 3, 0 };
2302 static const int transminus
[] = { 0, 0, 0, -1 };
2304 s
->i
= transS
[s
->i
];
2306 s
->i
= transH
[s
->i
];
2308 s
->i
= transminus
[s
->i
];
2313 crReturn(1); /* get another character */
2317 s
->vstring
= snewn(s
->vstrsize
, char);
2318 strcpy(s
->vstring
, "SSH-");
2322 crReturn(1); /* get another char */
2323 if (s
->vslen
>= s
->vstrsize
- 1) {
2325 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2327 s
->vstring
[s
->vslen
++] = c
;
2330 s
->version
[s
->i
] = '\0';
2332 } else if (s
->i
< sizeof(s
->version
) - 1)
2333 s
->version
[s
->i
++] = c
;
2334 } else if (c
== '\012')
2338 ssh
->agentfwd_enabled
= FALSE
;
2339 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2341 s
->vstring
[s
->vslen
] = 0;
2342 s
->vstring
[strcspn(s
->vstring
, "\015\012")] = '\0';/* remove EOL chars */
2343 logeventf(ssh
, "Server version: %s", s
->vstring
);
2344 ssh_detect_bugs(ssh
, s
->vstring
);
2347 * Decide which SSH protocol version to support.
2350 /* Anything strictly below "2.0" means protocol 1 is supported. */
2351 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2352 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2353 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2355 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2356 bombout(("SSH protocol version 1 required by user but not provided by server"));
2359 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2360 bombout(("SSH protocol version 2 required by user but not provided by server"));
2367 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2369 * Construct a v2 version string.
2371 verstring
= dupprintf("SSH-2.0-%s\015\012", sshver
);
2375 * Construct a v1 version string.
2377 verstring
= dupprintf("SSH-%s-%s\012",
2378 (ssh_versioncmp(s
->version
, "1.5") <= 0 ?
2379 s
->version
: "1.5"),
2384 ssh_fix_verstring(verstring
);
2386 if (ssh
->version
== 2) {
2388 * Hash our version string and their version string.
2390 SHA_Init(&ssh
->exhashbase
);
2391 sha_string(&ssh
->exhashbase
, verstring
,
2392 strcspn(verstring
, "\015\012"));
2393 sha_string(&ssh
->exhashbase
, s
->vstring
,
2394 strcspn(s
->vstring
, "\015\012"));
2397 * Initialise SSH-2 protocol.
2399 ssh
->protocol
= ssh2_protocol
;
2400 ssh2_protocol_setup(ssh
);
2401 ssh
->s_rdpkt
= ssh2_rdpkt
;
2404 * Initialise SSH-1 protocol.
2406 ssh
->protocol
= ssh1_protocol
;
2407 ssh1_protocol_setup(ssh
);
2408 ssh
->s_rdpkt
= ssh1_rdpkt
;
2410 logeventf(ssh
, "We claim version: %.*s",
2411 strcspn(verstring
, "\015\012"), verstring
);
2412 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2414 if (ssh
->version
== 2)
2415 do_ssh2_transport(ssh
, NULL
, -1, NULL
);
2418 logeventf(ssh
, "Using SSH protocol version %d", ssh
->version
);
2420 update_specials_menu(ssh
->frontend
);
2421 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2422 ssh
->pinger
= pinger_new(&ssh
->cfg
, &ssh_backend
, ssh
);
2429 static void ssh_process_incoming_data(Ssh ssh
,
2430 unsigned char **data
, int *datalen
)
2432 struct Packet
*pktin
= ssh
->s_rdpkt(ssh
, data
, datalen
);
2434 ssh
->protocol(ssh
, NULL
, 0, pktin
);
2435 ssh_free_packet(pktin
);
2439 static void ssh_queue_incoming_data(Ssh ssh
,
2440 unsigned char **data
, int *datalen
)
2442 bufchain_add(&ssh
->queued_incoming_data
, *data
, *datalen
);
2447 static void ssh_process_queued_incoming_data(Ssh ssh
)
2450 unsigned char *data
;
2453 while (!ssh
->frozen
&& bufchain_size(&ssh
->queued_incoming_data
)) {
2454 bufchain_prefix(&ssh
->queued_incoming_data
, &vdata
, &len
);
2458 while (!ssh
->frozen
&& len
> 0)
2459 ssh_process_incoming_data(ssh
, &data
, &len
);
2462 bufchain_consume(&ssh
->queued_incoming_data
, origlen
- len
);
2466 static void ssh_set_frozen(Ssh ssh
, int frozen
)
2469 sk_set_frozen(ssh
->s
, frozen
);
2470 ssh
->frozen
= frozen
;
2473 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2475 crBegin(ssh
->ssh_gotdata_crstate
);
2478 * To begin with, feed the characters one by one to the
2479 * protocol initialisation / selection function do_ssh_init().
2480 * When that returns 0, we're done with the initial greeting
2481 * exchange and can move on to packet discipline.
2484 int ret
; /* need not be kept across crReturn */
2486 crReturnV
; /* more data please */
2487 ret
= do_ssh_init(ssh
, *data
);
2495 * We emerge from that loop when the initial negotiation is
2496 * over and we have selected an s_rdpkt function. Now pass
2497 * everything to s_rdpkt, and then pass the resulting packets
2498 * to the proper protocol handler.
2504 * Process queued data if there is any.
2506 ssh_process_queued_incoming_data(ssh
);
2509 while (datalen
> 0) {
2511 ssh_queue_incoming_data(ssh
, &data
, &datalen
);
2513 ssh_process_incoming_data(ssh
, &data
, &datalen
);
2515 if (ssh
->state
== SSH_STATE_CLOSED
)
2523 static int ssh_do_close(Ssh ssh
, int notify_exit
)
2526 struct ssh_channel
*c
;
2528 ssh
->state
= SSH_STATE_CLOSED
;
2529 expire_timer_context(ssh
);
2534 notify_remote_exit(ssh
->frontend
);
2539 * Now we must shut down any port- and X-forwarded channels going
2540 * through this connection.
2542 if (ssh
->channels
) {
2543 while (NULL
!= (c
= index234(ssh
->channels
, 0))) {
2546 x11_close(c
->u
.x11
.s
);
2549 pfd_close(c
->u
.pfd
.s
);
2552 del234(ssh
->channels
, c
); /* moving next one to index 0 */
2553 if (ssh
->version
== 2)
2554 bufchain_clear(&c
->v
.v2
.outbuffer
);
2559 * Go through port-forwardings, and close any associated
2560 * listening sockets.
2562 if (ssh
->portfwds
) {
2563 struct ssh_portfwd
*pf
;
2564 while (NULL
!= (pf
= index234(ssh
->portfwds
, 0))) {
2565 /* Dispose of any listening socket. */
2567 pfd_terminate(pf
->local
);
2568 del234(ssh
->portfwds
, pf
); /* moving next one to index 0 */
2576 static void ssh_log(Plug plug
, int type
, SockAddr addr
, int port
,
2577 const char *error_msg
, int error_code
)
2579 Ssh ssh
= (Ssh
) plug
;
2580 char addrbuf
[256], *msg
;
2582 sk_getaddr(addr
, addrbuf
, lenof(addrbuf
));
2585 msg
= dupprintf("Connecting to %s port %d", addrbuf
, port
);
2587 msg
= dupprintf("Failed to connect to %s: %s", addrbuf
, error_msg
);
2593 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2596 Ssh ssh
= (Ssh
) plug
;
2597 int need_notify
= ssh_do_close(ssh
, FALSE
);
2599 if (!error_msg
&& !ssh
->close_expected
) {
2600 error_msg
= "Server unexpectedly closed network connection";
2604 notify_remote_exit(ssh
->frontend
);
2607 /* A socket error has occurred. */
2608 logevent(error_msg
);
2609 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2611 logevent("Server closed network connection");
2616 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2618 Ssh ssh
= (Ssh
) plug
;
2619 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2620 if (ssh
->state
== SSH_STATE_CLOSED
) {
2621 ssh_do_close(ssh
, TRUE
);
2627 static void ssh_sent(Plug plug
, int bufsize
)
2629 Ssh ssh
= (Ssh
) plug
;
2631 * If the send backlog on the SSH socket itself clears, we
2632 * should unthrottle the whole world if it was throttled.
2634 if (bufsize
< SSH_MAX_BACKLOG
)
2635 ssh_throttle_all(ssh
, 0, bufsize
);
2639 * Connect to specified host and port.
2640 * Returns an error message, or NULL on success.
2641 * Also places the canonical host name into `realhost'. It must be
2642 * freed by the caller.
2644 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2645 char **realhost
, int nodelay
, int keepalive
)
2647 static const struct plug_function_table fn_table
= {
2658 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2659 if (!ssh
->savedhost
)
2660 fatalbox("Out of memory");
2661 strcpy(ssh
->savedhost
, host
);
2664 port
= 22; /* default ssh port */
2665 ssh
->savedport
= port
;
2670 logeventf(ssh
, "Looking up host \"%s\"%s", host
,
2671 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV4 ?
" (IPv4)" :
2672 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV6 ?
" (IPv6)" : "")));
2673 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
,
2674 ssh
->cfg
.addressfamily
);
2675 if ((err
= sk_addr_error(addr
)) != NULL
) {
2683 ssh
->fn
= &fn_table
;
2684 ssh
->s
= new_connection(addr
, *realhost
, port
,
2685 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2686 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2688 notify_remote_exit(ssh
->frontend
);
2696 * Throttle or unthrottle the SSH connection.
2698 static void ssh1_throttle(Ssh ssh
, int adjust
)
2700 int old_count
= ssh
->v1_throttle_count
;
2701 ssh
->v1_throttle_count
+= adjust
;
2702 assert(ssh
->v1_throttle_count
>= 0);
2703 if (ssh
->v1_throttle_count
&& !old_count
) {
2704 ssh_set_frozen(ssh
, 1);
2705 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2706 ssh_set_frozen(ssh
, 0);
2711 * Throttle or unthrottle _all_ local data streams (for when sends
2712 * on the SSH connection itself back up).
2714 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2717 struct ssh_channel
*c
;
2719 if (enable
== ssh
->throttled_all
)
2721 ssh
->throttled_all
= enable
;
2722 ssh
->overall_bufsize
= bufsize
;
2725 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2727 case CHAN_MAINSESSION
:
2729 * This is treated separately, outside the switch.
2733 x11_override_throttle(c
->u
.x11
.s
, enable
);
2736 /* Agent channels require no buffer management. */
2739 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2746 * Username and password input, abstracted off into routines
2747 * reusable in several places - even between SSH-1 and SSH-2.
2750 /* Set up a username or password input loop on a given buffer. */
2751 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2753 ssh
->userpass_input_buffer
= buffer
;
2754 ssh
->userpass_input_buflen
= buflen
;
2755 ssh
->userpass_input_bufpos
= 0;
2756 ssh
->userpass_input_echo
= echo
;
2760 * Process some terminal data in the course of username/password
2761 * input. Returns >0 for success (line of input returned in
2762 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2763 * for inconclusive (keep waiting for more input please).
2765 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2770 switch (c
= *in
++) {
2773 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2774 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2779 if (ssh
->userpass_input_bufpos
> 0) {
2780 if (ssh
->userpass_input_echo
)
2781 c_write_str(ssh
, "\b \b");
2782 ssh
->userpass_input_bufpos
--;
2787 while (ssh
->userpass_input_bufpos
> 0) {
2788 if (ssh
->userpass_input_echo
)
2789 c_write_str(ssh
, "\b \b");
2790 ssh
->userpass_input_bufpos
--;
2799 * This simplistic check for printability is disabled
2800 * when we're doing password input, because some people
2801 * have control characters in their passwords.o
2803 if ((!ssh
->userpass_input_echo
||
2804 (c
>= ' ' && c
<= '~') ||
2805 ((unsigned char) c
>= 160))
2806 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2807 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2808 if (ssh
->userpass_input_echo
)
2809 c_write(ssh
, &c
, 1);
2817 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2819 Ssh ssh
= (Ssh
) sshv
;
2821 ssh
->agent_response
= reply
;
2822 ssh
->agent_response_len
= replylen
;
2824 if (ssh
->version
== 1)
2825 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2827 do_ssh2_authconn(ssh
, NULL
, -1, NULL
);
2830 static void ssh_dialog_callback(void *sshv
, int ret
)
2832 Ssh ssh
= (Ssh
) sshv
;
2834 ssh
->user_response
= ret
;
2836 if (ssh
->version
== 1)
2837 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2839 do_ssh2_transport(ssh
, NULL
, -1, NULL
);
2842 * This may have unfrozen the SSH connection, so do a
2845 ssh_process_queued_incoming_data(ssh
);
2848 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2850 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2852 void *sentreply
= reply
;
2855 /* Fake SSH_AGENT_FAILURE. */
2856 sentreply
= "\0\0\0\1\5";
2859 if (ssh
->version
== 2) {
2860 ssh2_add_channel_data(c
, sentreply
, replylen
);
2863 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2864 PKT_INT
, c
->remoteid
,
2867 PKT_DATA
, sentreply
, replylen
,
2876 * Handle the key exchange and user authentication phases.
2878 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
2879 struct Packet
*pktin
)
2882 unsigned char cookie
[8], *ptr
;
2883 struct RSAKey servkey
, hostkey
;
2884 struct MD5Context md5c
;
2885 struct do_ssh1_login_state
{
2887 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2888 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2889 int tried_publickey
, tried_agent
;
2890 int tis_auth_refused
, ccard_auth_refused
;
2891 unsigned char session_id
[16];
2894 void *publickey_blob
;
2895 int publickey_bloblen
;
2901 unsigned char request
[5], *response
, *p
;
2911 crState(do_ssh1_login_state
);
2913 crBegin(ssh
->do_ssh1_login_crstate
);
2918 if (pktin
->type
!= SSH1_SMSG_PUBLIC_KEY
) {
2919 bombout(("Public key packet not received"));
2923 logevent("Received public keys");
2925 ptr
= ssh_pkt_getdata(pktin
, 8);
2927 bombout(("SSH-1 public key packet stopped before random cookie"));
2930 memcpy(cookie
, ptr
, 8);
2932 if (!ssh1_pkt_getrsakey(pktin
, &servkey
, &s
->keystr1
) ||
2933 !ssh1_pkt_getrsakey(pktin
, &hostkey
, &s
->keystr2
)) {
2934 bombout(("Failed to read SSH-1 public keys from public key packet"));
2939 * Log the host key fingerprint.
2943 logevent("Host key fingerprint is:");
2944 strcpy(logmsg
, " ");
2945 hostkey
.comment
= NULL
;
2946 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2947 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2951 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(pktin
);
2952 s
->supported_ciphers_mask
= ssh_pkt_getuint32(pktin
);
2953 s
->supported_auths_mask
= ssh_pkt_getuint32(pktin
);
2955 ssh
->v1_local_protoflags
=
2956 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2957 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2960 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2961 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2962 MD5Update(&md5c
, cookie
, 8);
2963 MD5Final(s
->session_id
, &md5c
);
2965 for (i
= 0; i
< 32; i
++)
2966 ssh
->session_key
[i
] = random_byte();
2969 * Verify that the `bits' and `bytes' parameters match.
2971 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
2972 servkey
.bits
> servkey
.bytes
* 8) {
2973 bombout(("SSH-1 public keys were badly formatted"));
2977 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2979 s
->rsabuf
= snewn(s
->len
, unsigned char);
2981 fatalbox("Out of memory");
2984 * Verify the host key.
2988 * First format the key into a string.
2990 int len
= rsastr_len(&hostkey
);
2991 char fingerprint
[100];
2992 char *keystr
= snewn(len
, char);
2994 fatalbox("Out of memory");
2995 rsastr_fmt(keystr
, &hostkey
);
2996 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2998 ssh_set_frozen(ssh
, 1);
2999 s
->dlgret
= verify_ssh_host_key(ssh
->frontend
,
3000 ssh
->savedhost
, ssh
->savedport
,
3001 "rsa", keystr
, fingerprint
,
3002 ssh_dialog_callback
, ssh
);
3004 if (s
->dlgret
< 0) {
3008 bombout(("Unexpected data from server while waiting"
3009 " for user host key response"));
3012 } while (pktin
|| inlen
> 0);
3013 s
->dlgret
= ssh
->user_response
;
3015 ssh_set_frozen(ssh
, 0);
3017 if (s
->dlgret
== 0) {
3018 ssh
->close_expected
= TRUE
;
3019 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3024 for (i
= 0; i
< 32; i
++) {
3025 s
->rsabuf
[i
] = ssh
->session_key
[i
];
3027 s
->rsabuf
[i
] ^= s
->session_id
[i
];
3030 if (hostkey
.bytes
> servkey
.bytes
) {
3031 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
3033 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
3035 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
3037 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
3040 bombout(("SSH-1 public key encryptions failed due to bad formatting"));
3044 logevent("Encrypted session key");
3047 int cipher_chosen
= 0, warn
= 0;
3048 char *cipher_string
= NULL
;
3050 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
3051 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
3052 if (next_cipher
== CIPHER_WARN
) {
3053 /* If/when we choose a cipher, warn about it */
3055 } else if (next_cipher
== CIPHER_AES
) {
3056 /* XXX Probably don't need to mention this. */
3057 logevent("AES not supported in SSH-1, skipping");
3059 switch (next_cipher
) {
3060 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
3061 cipher_string
= "3DES"; break;
3062 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
3063 cipher_string
= "Blowfish"; break;
3064 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
3065 cipher_string
= "single-DES"; break;
3067 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
3071 if (!cipher_chosen
) {
3072 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
3073 bombout(("Server violates SSH-1 protocol by not "
3074 "supporting 3DES encryption"));
3076 /* shouldn't happen */
3077 bombout(("No supported ciphers found"));
3081 /* Warn about chosen cipher if necessary. */
3083 ssh_set_frozen(ssh
, 1);
3084 s
->dlgret
= askalg(ssh
->frontend
, "cipher", cipher_string
,
3085 ssh_dialog_callback
, ssh
);
3086 if (s
->dlgret
< 0) {
3090 bombout(("Unexpected data from server while waiting"
3091 " for user response"));
3094 } while (pktin
|| inlen
> 0);
3095 s
->dlgret
= ssh
->user_response
;
3097 ssh_set_frozen(ssh
, 0);
3098 if (s
->dlgret
== 0) {
3099 ssh
->close_expected
= TRUE
;
3100 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3106 switch (s
->cipher_type
) {
3107 case SSH_CIPHER_3DES
:
3108 logevent("Using 3DES encryption");
3110 case SSH_CIPHER_DES
:
3111 logevent("Using single-DES encryption");
3113 case SSH_CIPHER_BLOWFISH
:
3114 logevent("Using Blowfish encryption");
3118 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
3119 PKT_CHAR
, s
->cipher_type
,
3120 PKT_DATA
, cookie
, 8,
3121 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
3122 PKT_DATA
, s
->rsabuf
, s
->len
,
3123 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
3125 logevent("Trying to enable encryption...");
3129 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
3130 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
3132 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
3133 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
3134 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
3136 ssh
->crcda_ctx
= crcda_make_context();
3137 logevent("Installing CRC compensation attack detector");
3139 if (servkey
.modulus
) {
3140 sfree(servkey
.modulus
);
3141 servkey
.modulus
= NULL
;
3143 if (servkey
.exponent
) {
3144 sfree(servkey
.exponent
);
3145 servkey
.exponent
= NULL
;
3147 if (hostkey
.modulus
) {
3148 sfree(hostkey
.modulus
);
3149 hostkey
.modulus
= NULL
;
3151 if (hostkey
.exponent
) {
3152 sfree(hostkey
.exponent
);
3153 hostkey
.exponent
= NULL
;
3157 if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3158 bombout(("Encryption not successfully enabled"));
3162 logevent("Successfully started encryption");
3166 if (!*ssh
->cfg
.username
) {
3167 if (ssh_get_line
&& !ssh_getline_pw_only
) {
3168 if (!ssh_get_line("login as: ",
3169 s
->username
, sizeof(s
->username
), FALSE
)) {
3171 * get_line failed to get a username.
3174 logevent("No username provided. Abandoning session.");
3175 ssh
->close_expected
= TRUE
;
3176 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3180 int ret
; /* need not be kept over crReturn */
3181 c_write_str(ssh
, "login as: ");
3184 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
3186 crWaitUntil(!pktin
);
3187 ret
= process_userpass_input(ssh
, in
, inlen
);
3191 c_write_str(ssh
, "\r\n");
3194 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
3195 s
->username
[sizeof(s
->username
)-1] = '\0';
3198 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
3200 char userlog
[22 + sizeof(s
->username
)];
3201 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
3203 if (flags
& FLAG_INTERACTIVE
&&
3204 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
3205 strcat(userlog
, "\r\n");
3206 c_write_str(ssh
, userlog
);
3213 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
3214 /* We must not attempt PK auth. Pretend we've already tried it. */
3215 s
->tried_publickey
= s
->tried_agent
= 1;
3217 s
->tried_publickey
= s
->tried_agent
= 0;
3219 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
3220 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
3221 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
3222 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
3223 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
3224 s
->publickey_blob
= NULL
;
3226 s
->publickey_blob
= NULL
;
3228 while (pktin
->type
== SSH1_SMSG_FAILURE
) {
3229 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
3231 if (agent_exists() && !s
->tried_agent
) {
3233 * Attempt RSA authentication using Pageant.
3239 logevent("Pageant is running. Requesting keys.");
3241 /* Request the keys held by the agent. */
3242 PUT_32BIT(s
->request
, 1);
3243 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
3244 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
3245 ssh_agent_callback
, ssh
)) {
3249 bombout(("Unexpected data from server while waiting"
3250 " for agent response"));
3253 } while (pktin
|| inlen
> 0);
3254 r
= ssh
->agent_response
;
3255 s
->responselen
= ssh
->agent_response_len
;
3257 s
->response
= (unsigned char *) r
;
3258 if (s
->response
&& s
->responselen
>= 5 &&
3259 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
3260 s
->p
= s
->response
+ 5;
3261 s
->nkeys
= GET_32BIT(s
->p
);
3263 logeventf(ssh
, "Pageant has %d SSH-1 keys", s
->nkeys
);
3264 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
3265 logeventf(ssh
, "Trying Pageant key #%d", s
->keyi
);
3266 if (s
->publickey_blob
&&
3267 !memcmp(s
->p
, s
->publickey_blob
,
3268 s
->publickey_bloblen
)) {
3269 logevent("This key matches configured key file");
3270 s
->tried_publickey
= 1;
3275 do { /* do while (0) to make breaking easy */
3276 n
= ssh1_read_bignum
3277 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3282 n
= ssh1_read_bignum
3283 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3288 if (s
->responselen
- (s
->p
-s
->response
) < 4)
3290 s
->commentlen
= GET_32BIT(s
->p
);
3292 if (s
->responselen
- (s
->p
-s
->response
) <
3295 s
->commentp
= (char *)s
->p
;
3296 s
->p
+= s
->commentlen
;
3300 logevent("Pageant key list packet was truncated");
3304 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3305 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3307 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3308 logevent("Key refused");
3311 logevent("Received RSA challenge");
3312 if ((s
->challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3313 bombout(("Server's RSA challenge was badly formatted"));
3318 char *agentreq
, *q
, *ret
;
3321 len
= 1 + 4; /* message type, bit count */
3322 len
+= ssh1_bignum_length(s
->key
.exponent
);
3323 len
+= ssh1_bignum_length(s
->key
.modulus
);
3324 len
+= ssh1_bignum_length(s
->challenge
);
3325 len
+= 16; /* session id */
3326 len
+= 4; /* response format */
3327 agentreq
= snewn(4 + len
, char);
3328 PUT_32BIT(agentreq
, len
);
3330 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
3331 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
3333 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
3334 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
3335 q
+= ssh1_write_bignum(q
, s
->challenge
);
3336 memcpy(q
, s
->session_id
, 16);
3338 PUT_32BIT(q
, 1); /* response format */
3339 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
3340 ssh_agent_callback
, ssh
)) {
3345 bombout(("Unexpected data from server"
3346 " while waiting for agent"
3350 } while (pktin
|| inlen
> 0);
3351 vret
= ssh
->agent_response
;
3352 retlen
= ssh
->agent_response_len
;
3357 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
3358 logevent("Sending Pageant's response");
3359 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3360 PKT_DATA
, ret
+ 5, 16,
3364 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
3366 ("Pageant's response accepted");
3367 if (flags
& FLAG_VERBOSE
) {
3368 c_write_str(ssh
, "Authenticated using"
3370 c_write(ssh
, s
->commentp
,
3372 c_write_str(ssh
, "\" from agent\r\n");
3377 ("Pageant's response not accepted");
3380 ("Pageant failed to answer challenge");
3384 logevent("No reply received from Pageant");
3387 freebn(s
->key
.exponent
);
3388 freebn(s
->key
.modulus
);
3389 freebn(s
->challenge
);
3398 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
3399 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
3401 if (ssh
->cfg
.try_tis_auth
&&
3402 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3403 !s
->tis_auth_refused
) {
3404 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3405 logevent("Requested TIS authentication");
3406 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3408 if (pktin
->type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3409 logevent("TIS authentication declined");
3410 if (flags
& FLAG_INTERACTIVE
)
3411 c_write_str(ssh
, "TIS authentication refused.\r\n");
3412 s
->tis_auth_refused
= 1;
3418 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3420 bombout(("TIS challenge packet was badly formed"));
3423 c_write_str(ssh
, "Using TIS authentication.\r\n");
3424 logevent("Received TIS challenge");
3425 if (challengelen
> sizeof(s
->prompt
) - 1)
3426 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3427 memcpy(s
->prompt
, challenge
, challengelen
);
3428 /* Prompt heuristic comes from OpenSSH */
3429 strncpy(s
->prompt
+ challengelen
,
3430 memchr(s
->prompt
, '\n', challengelen
) ?
3431 "": "\r\nResponse: ",
3432 (sizeof s
->prompt
) - challengelen
);
3433 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
3436 if (ssh
->cfg
.try_tis_auth
&&
3437 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3438 !s
->ccard_auth_refused
) {
3439 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3440 logevent("Requested CryptoCard authentication");
3441 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3443 if (pktin
->type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3444 logevent("CryptoCard authentication declined");
3445 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3446 s
->ccard_auth_refused
= 1;
3452 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3454 bombout(("CryptoCard challenge packet was badly formed"));
3457 c_write_str(ssh
, "Using CryptoCard authentication.\r\n");
3458 logevent("Received CryptoCard challenge");
3459 if (challengelen
> sizeof(s
->prompt
) - 1)
3460 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3461 memcpy(s
->prompt
, challenge
, challengelen
);
3462 strncpy(s
->prompt
+ challengelen
,
3463 memchr(s
->prompt
, '\n', challengelen
) ?
3464 "" : "\r\nResponse: ",
3465 sizeof(s
->prompt
) - challengelen
);
3466 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
3469 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3470 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
3471 s
->username
, ssh
->savedhost
);
3473 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3474 char *comment
= NULL
;
3476 if (flags
& FLAG_VERBOSE
)
3477 c_write_str(ssh
, "Trying public key authentication.\r\n");
3478 logeventf(ssh
, "Trying public key \"%s\"",
3479 filename_to_str(&ssh
->cfg
.keyfile
));
3480 type
= key_type(&ssh
->cfg
.keyfile
);
3481 if (type
!= SSH_KEYTYPE_SSH1
) {
3482 char *msg
= dupprintf("Key is of wrong type (%s)",
3483 key_type_to_str(type
));
3485 c_write_str(ssh
, msg
);
3486 c_write_str(ssh
, "\r\n");
3488 s
->tried_publickey
= 1;
3491 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
3492 if (flags
& FLAG_VERBOSE
)
3493 c_write_str(ssh
, "No passphrase required.\r\n");
3496 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
3501 * Show password prompt, having first obtained it via a TIS
3502 * or CryptoCard exchange if we're doing TIS or CryptoCard
3506 if (!ssh_get_line(s
->prompt
, s
->password
,
3507 sizeof(s
->password
), TRUE
)) {
3509 * get_line failed to get a password (for example
3510 * because one was supplied on the command line
3511 * which has already failed to work). Terminate.
3513 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
3514 PKT_STR
, "No more passwords available to try",
3516 logevent("Unable to authenticate");
3517 connection_fatal(ssh
->frontend
, "Unable to authenticate");
3518 ssh
->close_expected
= TRUE
;
3519 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3523 /* Prompt may have come from server. We've munged it a bit, so
3524 * we know it to be zero-terminated at least once. */
3525 int ret
; /* need not be saved over crReturn */
3526 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3529 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3531 crWaitUntil(!pktin
);
3532 ret
= process_userpass_input(ssh
, in
, inlen
);
3536 c_write_str(ssh
, "\r\n");
3540 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3542 * Try public key authentication with the specified
3545 s
->tried_publickey
= 1;
3548 const char *error
= NULL
;
3549 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3552 c_write_str(ssh
, "Couldn't load private key from ");
3553 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3554 c_write_str(ssh
, " (");
3555 c_write_str(ssh
, error
);
3556 c_write_str(ssh
, ").\r\n");
3557 continue; /* go and try password */
3560 c_write_str(ssh
, "Wrong passphrase.\r\n");
3561 s
->tried_publickey
= 0;
3562 continue; /* try again */
3567 * Send a public key attempt.
3569 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3570 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3573 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3574 c_write_str(ssh
, "Server refused our public key.\r\n");
3575 continue; /* go and try password */
3577 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3578 bombout(("Bizarre response to offer of public key"));
3584 unsigned char buffer
[32];
3585 Bignum challenge
, response
;
3587 if ((challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3588 bombout(("Server's RSA challenge was badly formatted"));
3591 response
= rsadecrypt(challenge
, &s
->key
);
3592 freebn(s
->key
.private_exponent
);/* burn the evidence */
3594 for (i
= 0; i
< 32; i
++) {
3595 buffer
[i
] = bignum_byte(response
, 31 - i
);
3599 MD5Update(&md5c
, buffer
, 32);
3600 MD5Update(&md5c
, s
->session_id
, 16);
3601 MD5Final(buffer
, &md5c
);
3603 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3604 PKT_DATA
, buffer
, 16, PKT_END
);
3611 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3612 if (flags
& FLAG_VERBOSE
)
3613 c_write_str(ssh
, "Failed to authenticate with"
3614 " our public key.\r\n");
3615 continue; /* go and try password */
3616 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3617 bombout(("Bizarre response to RSA authentication response"));
3621 break; /* we're through! */
3623 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3625 * Defence against traffic analysis: we send a
3626 * whole bunch of packets containing strings of
3627 * different lengths. One of these strings is the
3628 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3629 * The others are all random data in
3630 * SSH1_MSG_IGNORE packets. This way a passive
3631 * listener can't tell which is the password, and
3632 * hence can't deduce the password length.
3634 * Anybody with a password length greater than 16
3635 * bytes is going to have enough entropy in their
3636 * password that a listener won't find it _that_
3637 * much help to know how long it is. So what we'll
3640 * - if password length < 16, we send 15 packets
3641 * containing string lengths 1 through 15
3643 * - otherwise, we let N be the nearest multiple
3644 * of 8 below the password length, and send 8
3645 * packets containing string lengths N through
3646 * N+7. This won't obscure the order of
3647 * magnitude of the password length, but it will
3648 * introduce a bit of extra uncertainty.
3650 * A few servers (the old 1.2.18 through 1.2.22)
3651 * can't deal with SSH1_MSG_IGNORE. For these
3652 * servers, we need an alternative defence. We make
3653 * use of the fact that the password is interpreted
3654 * as a C string: so we can append a NUL, then some
3657 * One server (a Cisco one) can deal with neither
3658 * SSH1_MSG_IGNORE _nor_ a padded password string.
3659 * For this server we are left with no defences
3660 * against password length sniffing.
3662 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3664 * The server can deal with SSH1_MSG_IGNORE, so
3665 * we can use the primary defence.
3667 int bottom
, top
, pwlen
, i
;
3670 pwlen
= strlen(s
->password
);
3672 bottom
= 0; /* zero length passwords are OK! :-) */
3675 bottom
= pwlen
& ~7;
3679 assert(pwlen
>= bottom
&& pwlen
<= top
);
3681 randomstr
= snewn(top
+ 1, char);
3683 for (i
= bottom
; i
<= top
; i
++) {
3685 defer_packet(ssh
, s
->pwpkt_type
,
3686 PKTT_PASSWORD
, PKT_STR
, s
->password
,
3687 PKTT_OTHER
, PKT_END
);
3689 for (j
= 0; j
< i
; j
++) {
3691 randomstr
[j
] = random_byte();
3692 } while (randomstr
[j
] == '\0');
3694 randomstr
[i
] = '\0';
3695 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3696 PKT_STR
, randomstr
, PKT_END
);
3699 logevent("Sending password with camouflage packets");
3700 ssh_pkt_defersend(ssh
);
3703 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3705 * The server can't deal with SSH1_MSG_IGNORE
3706 * but can deal with padded passwords, so we
3707 * can use the secondary defence.
3713 len
= strlen(s
->password
);
3714 if (len
< sizeof(string
)) {
3716 strcpy(string
, s
->password
);
3717 len
++; /* cover the zero byte */
3718 while (len
< sizeof(string
)) {
3719 string
[len
++] = (char) random_byte();
3724 logevent("Sending length-padded password");
3725 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3726 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3727 PKTT_OTHER
, PKT_END
);
3730 * The server has _both_
3731 * BUG_CHOKES_ON_SSH1_IGNORE and
3732 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3733 * therefore nothing we can do.
3736 len
= strlen(s
->password
);
3737 logevent("Sending unpadded password");
3738 send_packet(ssh
, s
->pwpkt_type
,
3739 PKTT_PASSWORD
, PKT_INT
, len
,
3740 PKT_DATA
, s
->password
, len
,
3741 PKTT_OTHER
, PKT_END
);
3744 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3745 PKT_STR
, s
->password
, PKTT_OTHER
, PKT_END
);
3748 logevent("Sent password");
3749 memset(s
->password
, 0, strlen(s
->password
));
3751 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3752 if (flags
& FLAG_VERBOSE
)
3753 c_write_str(ssh
, "Access denied\r\n");
3754 logevent("Authentication refused");
3755 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3756 bombout(("Strange packet received, type %d", pktin
->type
));
3761 logevent("Authentication successful");
3766 void sshfwd_close(struct ssh_channel
*c
)
3770 if (ssh
->state
== SSH_STATE_CLOSED
)
3773 if (c
&& !c
->closes
) {
3775 * If halfopen is true, we have sent
3776 * CHANNEL_OPEN for this channel, but it hasn't even been
3777 * acknowledged by the server. So we must set a close flag
3778 * on it now, and then when the server acks the channel
3779 * open, we can close it then.
3782 if (ssh
->version
== 1) {
3783 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3786 struct Packet
*pktout
;
3787 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3788 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
3789 ssh2_pkt_send(ssh
, pktout
);
3792 c
->closes
= 1; /* sent MSG_CLOSE */
3793 if (c
->type
== CHAN_X11
) {
3795 logevent("Forwarded X11 connection terminated");
3796 } else if (c
->type
== CHAN_SOCKDATA
||
3797 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3799 logevent("Forwarded port closed");
3804 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3808 if (ssh
->state
== SSH_STATE_CLOSED
)
3811 if (ssh
->version
== 1) {
3812 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3813 PKT_INT
, c
->remoteid
,
3815 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3816 PKTT_OTHER
, PKT_END
);
3818 * In SSH-1 we can return 0 here - implying that forwarded
3819 * connections are never individually throttled - because
3820 * the only circumstance that can cause throttling will be
3821 * the whole SSH connection backing up, in which case
3822 * _everything_ will be throttled as a whole.
3826 ssh2_add_channel_data(c
, buf
, len
);
3827 return ssh2_try_send(c
);
3831 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3835 if (ssh
->state
== SSH_STATE_CLOSED
)
3838 if (ssh
->version
== 1) {
3839 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3840 c
->v
.v1
.throttling
= 0;
3841 ssh1_throttle(ssh
, -1);
3844 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3848 static void ssh_queueing_handler(Ssh ssh
, struct Packet
*pktin
)
3850 struct queued_handler
*qh
= ssh
->qhead
;
3854 assert(pktin
->type
== qh
->msg1
|| pktin
->type
== qh
->msg2
);
3857 assert(ssh
->packet_dispatch
[qh
->msg1
] == ssh_queueing_handler
);
3858 ssh
->packet_dispatch
[qh
->msg1
] = NULL
;
3861 assert(ssh
->packet_dispatch
[qh
->msg2
] == ssh_queueing_handler
);
3862 ssh
->packet_dispatch
[qh
->msg2
] = NULL
;
3866 ssh
->qhead
= qh
->next
;
3868 if (ssh
->qhead
->msg1
> 0) {
3869 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg1
] == NULL
);
3870 ssh
->packet_dispatch
[ssh
->qhead
->msg1
] = ssh_queueing_handler
;
3872 if (ssh
->qhead
->msg2
> 0) {
3873 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg2
] == NULL
);
3874 ssh
->packet_dispatch
[ssh
->qhead
->msg2
] = ssh_queueing_handler
;
3877 ssh
->qhead
= ssh
->qtail
= NULL
;
3878 ssh
->packet_dispatch
[pktin
->type
] = NULL
;
3881 qh
->handler(ssh
, pktin
, qh
->ctx
);
3886 static void ssh_queue_handler(Ssh ssh
, int msg1
, int msg2
,
3887 chandler_fn_t handler
, void *ctx
)
3889 struct queued_handler
*qh
;
3891 qh
= snew(struct queued_handler
);
3894 qh
->handler
= handler
;
3898 if (ssh
->qtail
== NULL
) {
3902 assert(ssh
->packet_dispatch
[qh
->msg1
] == NULL
);
3903 ssh
->packet_dispatch
[qh
->msg1
] = ssh_queueing_handler
;
3906 assert(ssh
->packet_dispatch
[qh
->msg2
] == NULL
);
3907 ssh
->packet_dispatch
[qh
->msg2
] = ssh_queueing_handler
;
3910 ssh
->qtail
->next
= qh
;
3915 static void ssh_rportfwd_succfail(Ssh ssh
, struct Packet
*pktin
, void *ctx
)
3917 struct ssh_rportfwd
*rpf
, *pf
= (struct ssh_rportfwd
*)ctx
;
3919 if (pktin
->type
== (ssh
->version
== 1 ? SSH1_SMSG_SUCCESS
:
3920 SSH2_MSG_REQUEST_SUCCESS
)) {
3921 logeventf(ssh
, "Remote port forwarding from %s enabled",
3924 logeventf(ssh
, "Remote port forwarding from %s refused",
3927 rpf
= del234(ssh
->rportfwds
, pf
);
3933 static void ssh_setup_portfwd(Ssh ssh
, const Config
*cfg
)
3935 const char *portfwd_strptr
= cfg
->portfwd
;
3936 struct ssh_portfwd
*epf
;
3939 if (!ssh
->portfwds
) {
3940 ssh
->portfwds
= newtree234(ssh_portcmp
);
3943 * Go through the existing port forwardings and tag them
3944 * with status==DESTROY. Any that we want to keep will be
3945 * re-enabled (status==KEEP) as we go through the
3946 * configuration and find out which bits are the same as
3949 struct ssh_portfwd
*epf
;
3951 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3952 epf
->status
= DESTROY
;
3955 while (*portfwd_strptr
) {
3956 char address_family
, type
;
3957 int sport
,dport
,sserv
,dserv
;
3958 char sports
[256], dports
[256], saddr
[256], host
[256];
3961 address_family
= 'A';
3963 if (*portfwd_strptr
== 'A' ||
3964 *portfwd_strptr
== '4' ||
3965 *portfwd_strptr
== '6')
3966 address_family
= *portfwd_strptr
++;
3967 if (*portfwd_strptr
== 'L' ||
3968 *portfwd_strptr
== 'R' ||
3969 *portfwd_strptr
== 'D')
3970 type
= *portfwd_strptr
++;
3975 while (*portfwd_strptr
&& *portfwd_strptr
!= '\t') {
3976 if (*portfwd_strptr
== ':') {
3978 * We've seen a colon in the middle of the
3979 * source port number. This means that
3980 * everything we've seen until now is the
3981 * source _address_, so we'll move it into
3982 * saddr and start sports from the beginning
3987 if (ssh
->version
== 1 && type
== 'R') {
3988 logeventf(ssh
, "SSH-1 cannot handle remote source address "
3989 "spec \"%s\"; ignoring", sports
);
3991 strcpy(saddr
, sports
);
3994 if (n
< lenof(sports
)-1) sports
[n
++] = *portfwd_strptr
++;
3998 if (*portfwd_strptr
== '\t')
4001 while (*portfwd_strptr
&& *portfwd_strptr
!= ':') {
4002 if (n
< lenof(host
)-1) host
[n
++] = *portfwd_strptr
++;
4005 if (*portfwd_strptr
== ':')
4008 while (*portfwd_strptr
) {
4009 if (n
< lenof(dports
)-1) dports
[n
++] = *portfwd_strptr
++;
4013 dport
= atoi(dports
);
4017 dport
= net_service_lookup(dports
);
4019 logeventf(ssh
, "Service lookup failed for destination"
4020 " port \"%s\"", dports
);
4024 while (*portfwd_strptr
) portfwd_strptr
++;
4028 portfwd_strptr
++; /* eat the NUL and move to next one */
4030 sport
= atoi(sports
);
4034 sport
= net_service_lookup(sports
);
4036 logeventf(ssh
, "Service lookup failed for source"
4037 " port \"%s\"", sports
);
4040 if (sport
&& dport
) {
4041 /* Set up a description of the source port. */
4042 struct ssh_portfwd
*pfrec
, *epfrec
;
4044 pfrec
= snew(struct ssh_portfwd
);
4046 pfrec
->saddr
= *saddr ?
dupstr(saddr
) : NULL
;
4047 pfrec
->sserv
= sserv ?
dupstr(sports
) : NULL
;
4048 pfrec
->sport
= sport
;
4049 pfrec
->daddr
= *host ?
dupstr(host
) : NULL
;
4050 pfrec
->dserv
= dserv ?
dupstr(dports
) : NULL
;
4051 pfrec
->dport
= dport
;
4052 pfrec
->local
= NULL
;
4053 pfrec
->remote
= NULL
;
4054 pfrec
->addressfamily
= (address_family
== '4' ? ADDRTYPE_IPV4
:
4055 address_family
== '6' ? ADDRTYPE_IPV6
:
4058 epfrec
= add234(ssh
->portfwds
, pfrec
);
4059 if (epfrec
!= pfrec
) {
4061 * We already have a port forwarding with precisely
4062 * these parameters. Hence, no need to do anything;
4063 * simply tag the existing one as KEEP.
4065 epfrec
->status
= KEEP
;
4066 free_portfwd(pfrec
);
4068 pfrec
->status
= CREATE
;
4074 * Now go through and destroy any port forwardings which were
4077 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
4078 if (epf
->status
== DESTROY
) {
4081 message
= dupprintf("%s port forwarding from %s%s%d",
4082 epf
->type
== 'L' ?
"local" :
4083 epf
->type
== 'R' ?
"remote" : "dynamic",
4084 epf
->saddr ? epf
->saddr
: "",
4085 epf
->saddr ?
":" : "",
4088 if (epf
->type
!= 'D') {
4089 char *msg2
= dupprintf("%s to %s:%d", message
,
4090 epf
->daddr
, epf
->dport
);
4095 logeventf(ssh
, "Cancelling %s", message
);
4099 struct ssh_rportfwd
*rpf
= epf
->remote
;
4100 struct Packet
*pktout
;
4103 * Cancel the port forwarding at the server
4106 if (ssh
->version
== 1) {
4108 * We cannot cancel listening ports on the
4109 * server side in SSH-1! There's no message
4110 * to support it. Instead, we simply remove
4111 * the rportfwd record from the local end
4112 * so that any connections the server tries
4113 * to make on it are rejected.
4116 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
4117 ssh2_pkt_addstring(pktout
, "cancel-tcpip-forward");
4118 ssh2_pkt_addbool(pktout
, 0);/* _don't_ want reply */
4120 ssh2_pkt_addstring(pktout
, epf
->saddr
);
4121 } else if (ssh
->cfg
.rport_acceptall
) {
4122 /* XXX: ssh->cfg.rport_acceptall may not represent
4123 * what was used to open the original connection,
4124 * since it's reconfigurable. */
4125 ssh2_pkt_addstring(pktout
, "0.0.0.0");
4127 ssh2_pkt_addstring(pktout
, "127.0.0.1");
4129 ssh2_pkt_adduint32(pktout
, epf
->sport
);
4130 ssh2_pkt_send(ssh
, pktout
);
4133 del234(ssh
->rportfwds
, rpf
);
4135 } else if (epf
->local
) {
4136 pfd_terminate(epf
->local
);
4139 delpos234(ssh
->portfwds
, i
);
4141 i
--; /* so we don't skip one in the list */
4145 * And finally, set up any new port forwardings (status==CREATE).
4147 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
4148 if (epf
->status
== CREATE
) {
4149 char *sportdesc
, *dportdesc
;
4150 sportdesc
= dupprintf("%s%s%s%s%d%s",
4151 epf
->saddr ? epf
->saddr
: "",
4152 epf
->saddr ?
":" : "",
4153 epf
->sserv ? epf
->sserv
: "",
4154 epf
->sserv ?
"(" : "",
4156 epf
->sserv ?
")" : "");
4157 if (epf
->type
== 'D') {
4160 dportdesc
= dupprintf("%s:%s%s%d%s",
4162 epf
->dserv ? epf
->dserv
: "",
4163 epf
->dserv ?
"(" : "",
4165 epf
->dserv ?
")" : "");
4168 if (epf
->type
== 'L') {
4169 const char *err
= pfd_addforward(epf
->daddr
, epf
->dport
,
4170 epf
->saddr
, epf
->sport
,
4173 epf
->addressfamily
);
4175 logeventf(ssh
, "Local %sport %s forwarding to %s%s%s",
4176 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
4177 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
4178 sportdesc
, dportdesc
,
4179 err ?
" failed: " : "", err ? err
: "");
4180 } else if (epf
->type
== 'D') {
4181 const char *err
= pfd_addforward(NULL
, -1,
4182 epf
->saddr
, epf
->sport
,
4185 epf
->addressfamily
);
4187 logeventf(ssh
, "Local %sport %s SOCKS dynamic forwarding%s%s",
4188 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
4189 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
4191 err ?
" failed: " : "", err ? err
: "");
4193 struct ssh_rportfwd
*pf
;
4196 * Ensure the remote port forwardings tree exists.
4198 if (!ssh
->rportfwds
) {
4199 if (ssh
->version
== 1)
4200 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
4202 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
4205 pf
= snew(struct ssh_rportfwd
);
4206 strncpy(pf
->dhost
, epf
->daddr
, lenof(pf
->dhost
)-1);
4207 pf
->dhost
[lenof(pf
->dhost
)-1] = '\0';
4208 pf
->dport
= epf
->dport
;
4209 pf
->sport
= epf
->sport
;
4210 if (add234(ssh
->rportfwds
, pf
) != pf
) {
4211 logeventf(ssh
, "Duplicate remote port forwarding to %s:%d",
4212 epf
->daddr
, epf
->dport
);
4215 logeventf(ssh
, "Requesting remote port %s"
4216 " forward to %s", sportdesc
, dportdesc
);
4218 pf
->sportdesc
= sportdesc
;
4223 if (ssh
->version
== 1) {
4224 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
4225 PKT_INT
, epf
->sport
,
4226 PKT_STR
, epf
->daddr
,
4227 PKT_INT
, epf
->dport
,
4229 ssh_queue_handler(ssh
, SSH1_SMSG_SUCCESS
,
4231 ssh_rportfwd_succfail
, pf
);
4233 struct Packet
*pktout
;
4234 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
4235 ssh2_pkt_addstring(pktout
, "tcpip-forward");
4236 ssh2_pkt_addbool(pktout
, 1);/* want reply */
4238 ssh2_pkt_addstring(pktout
, epf
->saddr
);
4239 } else if (cfg
->rport_acceptall
) {
4240 ssh2_pkt_addstring(pktout
, "0.0.0.0");
4242 ssh2_pkt_addstring(pktout
, "127.0.0.1");
4244 ssh2_pkt_adduint32(pktout
, epf
->sport
);
4245 ssh2_pkt_send(ssh
, pktout
);
4247 ssh_queue_handler(ssh
, SSH2_MSG_REQUEST_SUCCESS
,
4248 SSH2_MSG_REQUEST_FAILURE
,
4249 ssh_rportfwd_succfail
, pf
);
4258 static void ssh1_smsg_stdout_stderr_data(Ssh ssh
, struct Packet
*pktin
)
4261 int stringlen
, bufsize
;
4263 ssh_pkt_getstring(pktin
, &string
, &stringlen
);
4264 if (string
== NULL
) {
4265 bombout(("Incoming terminal data packet was badly formed"));
4269 bufsize
= from_backend(ssh
->frontend
, pktin
->type
== SSH1_SMSG_STDERR_DATA
,
4271 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4272 ssh
->v1_stdout_throttling
= 1;
4273 ssh1_throttle(ssh
, +1);
4277 static void ssh1_smsg_x11_open(Ssh ssh
, struct Packet
*pktin
)
4279 /* Remote side is trying to open a channel to talk to our
4280 * X-Server. Give them back a local channel number. */
4281 struct ssh_channel
*c
;
4282 int remoteid
= ssh_pkt_getuint32(pktin
);
4284 logevent("Received X11 connect request");
4285 /* Refuse if X11 forwarding is disabled. */
4286 if (!ssh
->X11_fwd_enabled
) {
4287 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4288 PKT_INT
, remoteid
, PKT_END
);
4289 logevent("Rejected X11 connect request");
4291 c
= snew(struct ssh_channel
);
4294 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
4295 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
4296 logevent("Opening X11 forward connection failed");
4298 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4299 PKT_INT
, remoteid
, PKT_END
);
4302 ("Opening X11 forward connection succeeded");
4303 c
->remoteid
= remoteid
;
4304 c
->halfopen
= FALSE
;
4305 c
->localid
= alloc_channel_id(ssh
);
4307 c
->v
.v1
.throttling
= 0;
4308 c
->type
= CHAN_X11
; /* identify channel type */
4309 add234(ssh
->channels
, c
);
4310 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4311 PKT_INT
, c
->remoteid
, PKT_INT
,
4312 c
->localid
, PKT_END
);
4313 logevent("Opened X11 forward channel");
4318 static void ssh1_smsg_agent_open(Ssh ssh
, struct Packet
*pktin
)
4320 /* Remote side is trying to open a channel to talk to our
4321 * agent. Give them back a local channel number. */
4322 struct ssh_channel
*c
;
4323 int remoteid
= ssh_pkt_getuint32(pktin
);
4325 /* Refuse if agent forwarding is disabled. */
4326 if (!ssh
->agentfwd_enabled
) {
4327 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4328 PKT_INT
, remoteid
, PKT_END
);
4330 c
= snew(struct ssh_channel
);
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_AGENT
; /* identify channel type */
4338 c
->u
.a
.lensofar
= 0;
4339 add234(ssh
->channels
, c
);
4340 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4341 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
4346 static void ssh1_msg_port_open(Ssh ssh
, struct Packet
*pktin
)
4348 /* Remote side is trying to open a channel to talk to a
4349 * forwarded port. Give them back a local channel number. */
4350 struct ssh_channel
*c
;
4351 struct ssh_rportfwd pf
, *pfp
;
4356 c
= snew(struct ssh_channel
);
4359 remoteid
= ssh_pkt_getuint32(pktin
);
4360 ssh_pkt_getstring(pktin
, &host
, &hostsize
);
4361 port
= ssh_pkt_getuint32(pktin
);
4363 if (hostsize
>= lenof(pf
.dhost
))
4364 hostsize
= lenof(pf
.dhost
)-1;
4365 memcpy(pf
.dhost
, host
, hostsize
);
4366 pf
.dhost
[hostsize
] = '\0';
4368 pfp
= find234(ssh
->rportfwds
, &pf
, NULL
);
4371 logeventf(ssh
, "Rejected remote port open request for %s:%d",
4373 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4374 PKT_INT
, remoteid
, PKT_END
);
4376 logeventf(ssh
, "Received remote port open request for %s:%d",
4378 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
4379 c
, &ssh
->cfg
, pfp
->pfrec
->addressfamily
);
4381 logeventf(ssh
, "Port open failed: %s", e
);
4383 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4384 PKT_INT
, remoteid
, PKT_END
);
4386 c
->remoteid
= remoteid
;
4387 c
->halfopen
= FALSE
;
4388 c
->localid
= alloc_channel_id(ssh
);
4390 c
->v
.v1
.throttling
= 0;
4391 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
4392 add234(ssh
->channels
, c
);
4393 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4394 PKT_INT
, c
->remoteid
, PKT_INT
,
4395 c
->localid
, PKT_END
);
4396 logevent("Forwarded port opened successfully");
4401 static void ssh1_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
4403 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4404 unsigned int localid
= ssh_pkt_getuint32(pktin
);
4405 struct ssh_channel
*c
;
4407 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4408 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4409 c
->remoteid
= localid
;
4410 c
->halfopen
= FALSE
;
4411 c
->type
= CHAN_SOCKDATA
;
4412 c
->v
.v1
.throttling
= 0;
4413 pfd_confirm(c
->u
.pfd
.s
);
4416 if (c
&& c
->closes
) {
4418 * We have a pending close on this channel,
4419 * which we decided on before the server acked
4420 * the channel open. So now we know the
4421 * remoteid, we can close it again.
4423 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
4424 PKT_INT
, c
->remoteid
, PKT_END
);
4428 static void ssh1_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
4430 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4431 struct ssh_channel
*c
;
4433 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4434 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4435 logevent("Forwarded connection refused by server");
4436 pfd_close(c
->u
.pfd
.s
);
4437 del234(ssh
->channels
, c
);
4442 static void ssh1_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
4444 /* Remote side closes a channel. */
4445 unsigned i
= ssh_pkt_getuint32(pktin
);
4446 struct ssh_channel
*c
;
4447 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4448 if (c
&& !c
->halfopen
) {
4451 (pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
4453 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
4454 logevent("Forwarded X11 connection terminated");
4455 assert(c
->u
.x11
.s
!= NULL
);
4456 x11_close(c
->u
.x11
.s
);
4459 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
4460 logevent("Forwarded port closed");
4461 assert(c
->u
.pfd
.s
!= NULL
);
4462 pfd_close(c
->u
.pfd
.s
);
4466 c
->closes
|= (closetype
<< 2); /* seen this message */
4467 if (!(c
->closes
& closetype
)) {
4468 send_packet(ssh
, pktin
->type
, PKT_INT
, c
->remoteid
,
4470 c
->closes
|= closetype
; /* sent it too */
4473 if (c
->closes
== 15) {
4474 del234(ssh
->channels
, c
);
4478 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4479 pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
4480 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
4485 static void ssh1_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
4487 /* Data sent down one of our channels. */
4488 int i
= ssh_pkt_getuint32(pktin
);
4491 struct ssh_channel
*c
;
4493 ssh_pkt_getstring(pktin
, &p
, &len
);
4495 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4500 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
4503 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
4506 /* Data for an agent message. Buffer it. */
4508 if (c
->u
.a
.lensofar
< 4) {
4509 unsigned int l
= min(4 - c
->u
.a
.lensofar
, len
);
4510 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
4514 c
->u
.a
.lensofar
+= l
;
4516 if (c
->u
.a
.lensofar
== 4) {
4518 4 + GET_32BIT(c
->u
.a
.msglen
);
4519 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
4521 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
4523 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
4525 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
4527 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
4531 c
->u
.a
.lensofar
+= l
;
4533 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
4536 if (agent_query(c
->u
.a
.message
,
4539 ssh_agentf_callback
, c
))
4540 ssh_agentf_callback(c
, reply
, replylen
);
4541 sfree(c
->u
.a
.message
);
4542 c
->u
.a
.lensofar
= 0;
4545 bufsize
= 0; /* agent channels never back up */
4548 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4549 c
->v
.v1
.throttling
= 1;
4550 ssh1_throttle(ssh
, +1);
4555 static void ssh1_smsg_exit_status(Ssh ssh
, struct Packet
*pktin
)
4557 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
4558 logeventf(ssh
, "Server sent command exit status %d", ssh
->exitcode
);
4559 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
4561 * In case `helpful' firewalls or proxies tack
4562 * extra human-readable text on the end of the
4563 * session which we might mistake for another
4564 * encrypted packet, we close the session once
4565 * we've sent EXIT_CONFIRMATION.
4567 ssh
->close_expected
= TRUE
;
4568 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4571 /* Helper function to deal with sending tty modes for REQUEST_PTY */
4572 static void ssh1_send_ttymode(void *data
, char *mode
, char *val
)
4574 struct Packet
*pktout
= (struct Packet
*)data
;
4576 unsigned int arg
= 0;
4577 while (strcmp(mode
, ssh_ttymodes
[i
].mode
) != 0) i
++;
4578 if (i
== lenof(ssh_ttymodes
)) return;
4579 switch (ssh_ttymodes
[i
].type
) {
4581 arg
= ssh_tty_parse_specchar(val
);
4584 arg
= ssh_tty_parse_boolean(val
);
4587 ssh2_pkt_addbyte(pktout
, ssh_ttymodes
[i
].opcode
);
4588 ssh2_pkt_addbyte(pktout
, arg
);
4592 static void do_ssh1_connection(Ssh ssh
, unsigned char *in
, int inlen
,
4593 struct Packet
*pktin
)
4595 crBegin(ssh
->do_ssh1_connection_crstate
);
4597 ssh
->packet_dispatch
[SSH1_SMSG_STDOUT_DATA
] =
4598 ssh
->packet_dispatch
[SSH1_SMSG_STDERR_DATA
] =
4599 ssh1_smsg_stdout_stderr_data
;
4601 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
] =
4602 ssh1_msg_channel_open_confirmation
;
4603 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_FAILURE
] =
4604 ssh1_msg_channel_open_failure
;
4605 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE
] =
4606 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
] =
4607 ssh1_msg_channel_close
;
4608 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_DATA
] = ssh1_msg_channel_data
;
4609 ssh
->packet_dispatch
[SSH1_SMSG_EXIT_STATUS
] = ssh1_smsg_exit_status
;
4611 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
4612 logevent("Requesting agent forwarding");
4613 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
4617 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4618 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4619 bombout(("Protocol confusion"));
4621 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4622 logevent("Agent forwarding refused");
4624 logevent("Agent forwarding enabled");
4625 ssh
->agentfwd_enabled
= TRUE
;
4626 ssh
->packet_dispatch
[SSH1_SMSG_AGENT_OPEN
] = ssh1_smsg_agent_open
;
4630 if (ssh
->cfg
.x11_forward
) {
4631 char proto
[20], data
[64];
4632 logevent("Requesting X11 forwarding");
4633 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
4634 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
4635 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
4637 * Note that while we blank the X authentication data here, we don't
4638 * take any special action to blank the start of an X11 channel,
4639 * so using MIT-MAGIC-COOKIE-1 and actually opening an X connection
4640 * without having session blanking enabled is likely to leak your
4641 * cookie into the log.
4643 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
4644 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4646 PKTT_PASSWORD
, PKT_STR
, data
, PKTT_OTHER
,
4647 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
4650 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4652 PKTT_PASSWORD
, PKT_STR
, data
, PKTT_OTHER
, PKT_END
);
4657 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4658 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4659 bombout(("Protocol confusion"));
4661 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4662 logevent("X11 forwarding refused");
4664 logevent("X11 forwarding enabled");
4665 ssh
->X11_fwd_enabled
= TRUE
;
4666 ssh
->packet_dispatch
[SSH1_SMSG_X11_OPEN
] = ssh1_smsg_x11_open
;
4670 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
4671 ssh
->packet_dispatch
[SSH1_MSG_PORT_OPEN
] = ssh1_msg_port_open
;
4673 if (!ssh
->cfg
.nopty
) {
4675 /* Unpick the terminal-speed string. */
4676 /* XXX perhaps we should allow no speeds to be sent. */
4677 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
4678 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
4679 /* Send the pty request. */
4680 pkt
= ssh1_pkt_init(SSH1_CMSG_REQUEST_PTY
);
4681 ssh_pkt_addstring(pkt
, ssh
->cfg
.termtype
);
4682 ssh_pkt_adduint32(pkt
, ssh
->term_height
);
4683 ssh_pkt_adduint32(pkt
, ssh
->term_width
);
4684 ssh_pkt_adduint32(pkt
, 0); /* width in pixels */
4685 ssh_pkt_adduint32(pkt
, 0); /* height in pixels */
4686 parse_ttymodes(ssh
, ssh
->cfg
.ttymodes
,
4687 ssh1_send_ttymode
, (void *)pkt
);
4688 ssh_pkt_addbyte(pkt
, SSH1_TTY_OP_ISPEED
);
4689 ssh_pkt_adduint32(pkt
, ssh
->ispeed
);
4690 ssh_pkt_addbyte(pkt
, SSH1_TTY_OP_OSPEED
);
4691 ssh_pkt_adduint32(pkt
, ssh
->ospeed
);
4692 ssh_pkt_addbyte(pkt
, SSH_TTY_OP_END
);
4694 ssh
->state
= SSH_STATE_INTERMED
;
4698 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4699 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4700 bombout(("Protocol confusion"));
4702 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4703 c_write_str(ssh
, "Server refused to allocate pty\r\n");
4704 ssh
->editing
= ssh
->echoing
= 1;
4706 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
4707 ssh
->ospeed
, ssh
->ispeed
);
4709 ssh
->editing
= ssh
->echoing
= 1;
4712 if (ssh
->cfg
.compression
) {
4713 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
4717 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4718 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4719 bombout(("Protocol confusion"));
4721 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4722 c_write_str(ssh
, "Server refused to compress\r\n");
4724 logevent("Started compression");
4725 ssh
->v1_compressing
= TRUE
;
4726 ssh
->cs_comp_ctx
= zlib_compress_init();
4727 logevent("Initialised zlib (RFC1950) compression");
4728 ssh
->sc_comp_ctx
= zlib_decompress_init();
4729 logevent("Initialised zlib (RFC1950) decompression");
4733 * Start the shell or command.
4735 * Special case: if the first-choice command is an SSH-2
4736 * subsystem (hence not usable here) and the second choice
4737 * exists, we fall straight back to that.
4740 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
4742 if (!cmd
) cmd
= ssh
->cfg
.remote_cmd
;
4744 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
4745 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
4746 ssh
->fallback_cmd
= TRUE
;
4749 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
4751 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
4752 logevent("Started session");
4755 ssh
->state
= SSH_STATE_SESSION
;
4756 if (ssh
->size_needed
)
4757 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
4758 if (ssh
->eof_needed
)
4759 ssh_special(ssh
, TS_EOF
);
4762 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
4764 ssh
->channels
= newtree234(ssh_channelcmp
);
4768 * By this point, most incoming packets are already being
4769 * handled by the dispatch table, and we need only pay
4770 * attention to the unusual ones.
4775 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
4776 /* may be from EXEC_SHELL on some servers */
4777 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4778 /* may be from EXEC_SHELL on some servers
4779 * if no pty is available or in other odd cases. Ignore */
4781 bombout(("Strange packet received: type %d", pktin
->type
));
4786 int len
= min(inlen
, 512);
4787 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4788 PKT_INT
, len
, PKT_DATA
, in
, len
,
4789 PKTT_OTHER
, PKT_END
);
4800 * Handle the top-level SSH-2 protocol.
4802 static void ssh1_msg_debug(Ssh ssh
, struct Packet
*pktin
)
4807 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4808 logeventf(ssh
, "Remote debug message: %.*s", msglen
, msg
);
4811 static void ssh1_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
4813 /* log reason code in disconnect message */
4817 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4818 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen
, msg
));
4821 static void ssh_msg_ignore(Ssh ssh
, struct Packet
*pktin
)
4823 /* Do nothing, because we're ignoring it! Duhh. */
4826 static void ssh1_protocol_setup(Ssh ssh
)
4831 * Most messages are handled by the coroutines.
4833 for (i
= 0; i
< 256; i
++)
4834 ssh
->packet_dispatch
[i
] = NULL
;
4837 * These special message types we install handlers for.
4839 ssh
->packet_dispatch
[SSH1_MSG_DISCONNECT
] = ssh1_msg_disconnect
;
4840 ssh
->packet_dispatch
[SSH1_MSG_IGNORE
] = ssh_msg_ignore
;
4841 ssh
->packet_dispatch
[SSH1_MSG_DEBUG
] = ssh1_msg_debug
;
4844 static void ssh1_protocol(Ssh ssh
, void *vin
, int inlen
,
4845 struct Packet
*pktin
)
4847 unsigned char *in
=(unsigned char*)vin
;
4848 if (ssh
->state
== SSH_STATE_CLOSED
)
4851 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
4852 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
4856 if (!ssh
->protocol_initial_phase_done
) {
4857 if (do_ssh1_login(ssh
, in
, inlen
, pktin
))
4858 ssh
->protocol_initial_phase_done
= TRUE
;
4863 do_ssh1_connection(ssh
, in
, inlen
, pktin
);
4867 * Utility routine for decoding comma-separated strings in KEXINIT.
4869 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
4872 if (!needle
|| !haystack
) /* protect against null pointers */
4874 needlen
= strlen(needle
);
4877 * Is it at the start of the string?
4879 if (haylen
>= needlen
&& /* haystack is long enough */
4880 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4881 (haylen
== needlen
|| haystack
[needlen
] == ',')
4882 /* either , or EOS follows */
4886 * If not, search for the next comma and resume after that.
4887 * If no comma found, terminate.
4889 while (haylen
> 0 && *haystack
!= ',')
4890 haylen
--, haystack
++;
4893 haylen
--, haystack
++; /* skip over comma itself */
4898 * Similar routine for checking whether we have the first string in a list.
4900 static int first_in_commasep_string(char *needle
, char *haystack
, int haylen
)
4903 if (!needle
|| !haystack
) /* protect against null pointers */
4905 needlen
= strlen(needle
);
4907 * Is it at the start of the string?
4909 if (haylen
>= needlen
&& /* haystack is long enough */
4910 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4911 (haylen
== needlen
|| haystack
[needlen
] == ',')
4912 /* either , or EOS follows */
4920 * SSH-2 key creation method.
4922 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
4923 unsigned char *sessid
, char chr
,
4924 unsigned char *keyspace
)
4927 /* First 20 bytes. */
4929 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4931 SHA_Bytes(&s
, H
, 20);
4932 SHA_Bytes(&s
, &chr
, 1);
4933 SHA_Bytes(&s
, sessid
, 20);
4934 SHA_Final(&s
, keyspace
);
4935 /* Next 20 bytes. */
4937 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4939 SHA_Bytes(&s
, H
, 20);
4940 SHA_Bytes(&s
, keyspace
, 20);
4941 SHA_Final(&s
, keyspace
+ 20);
4945 * Handle the SSH-2 transport layer.
4947 static int do_ssh2_transport(Ssh ssh
, void *vin
, int inlen
,
4948 struct Packet
*pktin
)
4950 unsigned char *in
= (unsigned char *)vin
;
4951 struct do_ssh2_transport_state
{
4952 int nbits
, pbits
, warn_kex
, warn_cscipher
, warn_sccipher
;
4953 Bignum p
, g
, e
, f
, K
;
4954 int kex_init_value
, kex_reply_value
;
4955 const struct ssh_mac
**maclist
;
4957 const struct ssh2_cipher
*cscipher_tobe
;
4958 const struct ssh2_cipher
*sccipher_tobe
;
4959 const struct ssh_mac
*csmac_tobe
;
4960 const struct ssh_mac
*scmac_tobe
;
4961 const struct ssh_compress
*cscomp_tobe
;
4962 const struct ssh_compress
*sccomp_tobe
;
4963 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4964 int hostkeylen
, siglen
;
4965 void *hkey
; /* actual host key */
4966 unsigned char exchange_hash
[20];
4967 int n_preferred_kex
;
4968 const struct ssh_kex
*preferred_kex
[KEX_MAX
];
4969 int n_preferred_ciphers
;
4970 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
4971 const struct ssh_compress
*preferred_comp
;
4972 int got_session_id
, activated_authconn
;
4973 struct Packet
*pktout
;
4978 crState(do_ssh2_transport_state
);
4980 crBegin(ssh
->do_ssh2_transport_crstate
);
4982 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
4983 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
4984 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
4986 s
->got_session_id
= s
->activated_authconn
= FALSE
;
4989 * Be prepared to work around the buggy MAC problem.
4991 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
4992 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
4994 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
4997 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_KEX_MASK
;
4999 int i
, j
, commalist_started
;
5002 * Set up the preferred key exchange. (NULL => warn below here)
5004 s
->n_preferred_kex
= 0;
5005 for (i
= 0; i
< KEX_MAX
; i
++) {
5006 switch (ssh
->cfg
.ssh_kexlist
[i
]) {
5008 s
->preferred_kex
[s
->n_preferred_kex
++] =
5009 &ssh_diffiehellman_gex
;
5012 s
->preferred_kex
[s
->n_preferred_kex
++] =
5013 &ssh_diffiehellman_group14
;
5016 s
->preferred_kex
[s
->n_preferred_kex
++] =
5017 &ssh_diffiehellman_group1
;
5020 /* Flag for later. Don't bother if it's the last in
5022 if (i
< KEX_MAX
- 1) {
5023 s
->preferred_kex
[s
->n_preferred_kex
++] = NULL
;
5030 * Set up the preferred ciphers. (NULL => warn below here)
5032 s
->n_preferred_ciphers
= 0;
5033 for (i
= 0; i
< CIPHER_MAX
; i
++) {
5034 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
5035 case CIPHER_BLOWFISH
:
5036 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
5039 if (ssh
->cfg
.ssh2_des_cbc
) {
5040 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
5044 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
5047 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
5049 case CIPHER_ARCFOUR
:
5050 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_arcfour
;
5053 /* Flag for later. Don't bother if it's the last in
5055 if (i
< CIPHER_MAX
- 1) {
5056 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
5063 * Set up preferred compression.
5065 if (ssh
->cfg
.compression
)
5066 s
->preferred_comp
= &ssh_zlib
;
5068 s
->preferred_comp
= &ssh_comp_none
;
5071 * Enable queueing of outgoing auth- or connection-layer
5072 * packets while we are in the middle of a key exchange.
5074 ssh
->queueing
= TRUE
;
5077 * Flag that KEX is in progress.
5079 ssh
->kex_in_progress
= TRUE
;
5082 * Construct and send our key exchange packet.
5084 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEXINIT
);
5085 for (i
= 0; i
< 16; i
++)
5086 ssh2_pkt_addbyte(s
->pktout
, (unsigned char) random_byte());
5087 /* List key exchange algorithms. */
5088 ssh2_pkt_addstring_start(s
->pktout
);
5089 commalist_started
= 0;
5090 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
5091 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
5092 if (!k
) continue; /* warning flag */
5093 if (commalist_started
)
5094 ssh2_pkt_addstring_str(s
->pktout
, ",");
5095 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_kex
[i
]->name
);
5096 commalist_started
= 1;
5098 /* List server host key algorithms. */
5099 ssh2_pkt_addstring_start(s
->pktout
);
5100 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
5101 ssh2_pkt_addstring_str(s
->pktout
, hostkey_algs
[i
]->name
);
5102 if (i
< lenof(hostkey_algs
) - 1)
5103 ssh2_pkt_addstring_str(s
->pktout
, ",");
5105 /* List client->server encryption algorithms. */
5106 ssh2_pkt_addstring_start(s
->pktout
);
5107 commalist_started
= 0;
5108 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5109 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5110 if (!c
) continue; /* warning flag */
5111 for (j
= 0; j
< c
->nciphers
; j
++) {
5112 if (commalist_started
)
5113 ssh2_pkt_addstring_str(s
->pktout
, ",");
5114 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
5115 commalist_started
= 1;
5118 /* List server->client encryption algorithms. */
5119 ssh2_pkt_addstring_start(s
->pktout
);
5120 commalist_started
= 0;
5121 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5122 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5123 if (!c
) continue; /* warning flag */
5124 for (j
= 0; j
< c
->nciphers
; j
++) {
5125 if (commalist_started
)
5126 ssh2_pkt_addstring_str(s
->pktout
, ",");
5127 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
5128 commalist_started
= 1;
5131 /* List client->server MAC algorithms. */
5132 ssh2_pkt_addstring_start(s
->pktout
);
5133 for (i
= 0; i
< s
->nmacs
; i
++) {
5134 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
5135 if (i
< s
->nmacs
- 1)
5136 ssh2_pkt_addstring_str(s
->pktout
, ",");
5138 /* List server->client MAC algorithms. */
5139 ssh2_pkt_addstring_start(s
->pktout
);
5140 for (i
= 0; i
< s
->nmacs
; i
++) {
5141 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
5142 if (i
< s
->nmacs
- 1)
5143 ssh2_pkt_addstring_str(s
->pktout
, ",");
5145 /* List client->server compression algorithms. */
5146 ssh2_pkt_addstring_start(s
->pktout
);
5147 assert(lenof(compressions
) > 1);
5148 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
5149 for (i
= 0; i
< lenof(compressions
); i
++) {
5150 const struct ssh_compress
*c
= compressions
[i
];
5151 if (c
!= s
->preferred_comp
) {
5152 ssh2_pkt_addstring_str(s
->pktout
, ",");
5153 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
5156 /* List server->client compression algorithms. */
5157 ssh2_pkt_addstring_start(s
->pktout
);
5158 assert(lenof(compressions
) > 1);
5159 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
5160 for (i
= 0; i
< lenof(compressions
); i
++) {
5161 const struct ssh_compress
*c
= compressions
[i
];
5162 if (c
!= s
->preferred_comp
) {
5163 ssh2_pkt_addstring_str(s
->pktout
, ",");
5164 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
5167 /* List client->server languages. Empty list. */
5168 ssh2_pkt_addstring_start(s
->pktout
);
5169 /* List server->client languages. Empty list. */
5170 ssh2_pkt_addstring_start(s
->pktout
);
5171 /* First KEX packet does _not_ follow, because we're not that brave. */
5172 ssh2_pkt_addbool(s
->pktout
, FALSE
);
5174 ssh2_pkt_adduint32(s
->pktout
, 0);
5177 ssh
->exhash
= ssh
->exhashbase
;
5178 sha_string(&ssh
->exhash
, s
->pktout
->data
+ 5, s
->pktout
->length
- 5);
5180 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5184 if (pktin
->length
> 5)
5185 sha_string(&ssh
->exhash
, pktin
->data
+ 5, pktin
->length
- 5);
5188 * Now examine the other side's KEXINIT to see what we're up
5192 char *str
, *preferred
;
5195 if (pktin
->type
!= SSH2_MSG_KEXINIT
) {
5196 bombout(("expected key exchange packet from server"));
5200 ssh
->hostkey
= NULL
;
5201 s
->cscipher_tobe
= NULL
;
5202 s
->sccipher_tobe
= NULL
;
5203 s
->csmac_tobe
= NULL
;
5204 s
->scmac_tobe
= NULL
;
5205 s
->cscomp_tobe
= NULL
;
5206 s
->sccomp_tobe
= NULL
;
5207 s
->warn_kex
= s
->warn_cscipher
= s
->warn_sccipher
= FALSE
;
5209 pktin
->savedpos
+= 16; /* skip garbage cookie */
5210 ssh_pkt_getstring(pktin
, &str
, &len
); /* key exchange algorithms */
5213 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
5214 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
5218 if (!preferred
) preferred
= k
->name
;
5219 if (in_commasep_string(k
->name
, str
, len
))
5226 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
5227 str ? str
: "(null)"));
5231 * Note that the server's guess is considered wrong if it doesn't match
5232 * the first algorithm in our list, even if it's still the algorithm
5235 s
->guessok
= first_in_commasep_string(preferred
, str
, len
);
5236 ssh_pkt_getstring(pktin
, &str
, &len
); /* host key algorithms */
5237 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
5238 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
5239 ssh
->hostkey
= hostkey_algs
[i
];
5243 s
->guessok
= s
->guessok
&&
5244 first_in_commasep_string(hostkey_algs
[0]->name
, str
, len
);
5245 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server cipher */
5246 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5247 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5249 s
->warn_cscipher
= TRUE
;
5251 for (j
= 0; j
< c
->nciphers
; j
++) {
5252 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
5253 s
->cscipher_tobe
= c
->list
[j
];
5258 if (s
->cscipher_tobe
)
5261 if (!s
->cscipher_tobe
) {
5262 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
5263 str ? str
: "(null)"));
5267 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client cipher */
5268 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5269 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5271 s
->warn_sccipher
= TRUE
;
5273 for (j
= 0; j
< c
->nciphers
; j
++) {
5274 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
5275 s
->sccipher_tobe
= c
->list
[j
];
5280 if (s
->sccipher_tobe
)
5283 if (!s
->sccipher_tobe
) {
5284 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
5285 str ? str
: "(null)"));
5289 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server mac */
5290 for (i
= 0; i
< s
->nmacs
; i
++) {
5291 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5292 s
->csmac_tobe
= s
->maclist
[i
];
5296 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client mac */
5297 for (i
= 0; i
< s
->nmacs
; i
++) {
5298 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5299 s
->scmac_tobe
= s
->maclist
[i
];
5303 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server compression */
5304 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5305 const struct ssh_compress
*c
=
5306 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5307 if (in_commasep_string(c
->name
, str
, len
)) {
5312 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client compression */
5313 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5314 const struct ssh_compress
*c
=
5315 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5316 if (in_commasep_string(c
->name
, str
, len
)) {
5321 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server language */
5322 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client language */
5323 s
->ignorepkt
= ssh2_pkt_getbool(pktin
) && !s
->guessok
;
5326 ssh_set_frozen(ssh
, 1);
5327 s
->dlgret
= askalg(ssh
->frontend
, "key-exchange algorithm",
5329 ssh_dialog_callback
, ssh
);
5330 if (s
->dlgret
< 0) {
5334 bombout(("Unexpected data from server while"
5335 " waiting for user response"));
5338 } while (pktin
|| inlen
> 0);
5339 s
->dlgret
= ssh
->user_response
;
5341 ssh_set_frozen(ssh
, 0);
5342 if (s
->dlgret
== 0) {
5343 ssh
->close_expected
= TRUE
;
5344 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5349 if (s
->warn_cscipher
) {
5350 ssh_set_frozen(ssh
, 1);
5351 s
->dlgret
= askalg(ssh
->frontend
,
5352 "client-to-server cipher",
5353 s
->cscipher_tobe
->name
,
5354 ssh_dialog_callback
, ssh
);
5355 if (s
->dlgret
< 0) {
5359 bombout(("Unexpected data from server while"
5360 " waiting for user response"));
5363 } while (pktin
|| inlen
> 0);
5364 s
->dlgret
= ssh
->user_response
;
5366 ssh_set_frozen(ssh
, 0);
5367 if (s
->dlgret
== 0) {
5368 ssh
->close_expected
= TRUE
;
5369 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5374 if (s
->warn_sccipher
) {
5375 ssh_set_frozen(ssh
, 1);
5376 s
->dlgret
= askalg(ssh
->frontend
,
5377 "server-to-client cipher",
5378 s
->sccipher_tobe
->name
,
5379 ssh_dialog_callback
, ssh
);
5380 if (s
->dlgret
< 0) {
5384 bombout(("Unexpected data from server while"
5385 " waiting for user response"));
5388 } while (pktin
|| inlen
> 0);
5389 s
->dlgret
= ssh
->user_response
;
5391 ssh_set_frozen(ssh
, 0);
5392 if (s
->dlgret
== 0) {
5393 ssh
->close_expected
= TRUE
;
5394 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5399 if (s
->ignorepkt
) /* first_kex_packet_follows */
5400 crWaitUntil(pktin
); /* Ignore packet */
5404 * Work out the number of bits of key we will need from the key
5405 * exchange. We start with the maximum key length of either
5411 csbits
= s
->cscipher_tobe
->keylen
;
5412 scbits
= s
->sccipher_tobe
->keylen
;
5413 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
5415 /* The keys only have 160-bit entropy, since they're based on
5416 * a SHA-1 hash. So cap the key size at 160 bits. */
5421 * If we're doing Diffie-Hellman group exchange, start by
5422 * requesting a group.
5424 if (!ssh
->kex
->pdata
) {
5425 logevent("Doing Diffie-Hellman group exchange");
5426 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
5428 * Work out how big a DH group we will need to allow that
5431 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
5432 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
5433 ssh2_pkt_adduint32(s
->pktout
, s
->pbits
);
5434 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5437 if (pktin
->type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
5438 bombout(("expected key exchange group packet from server"));
5441 s
->p
= ssh2_pkt_getmp(pktin
);
5442 s
->g
= ssh2_pkt_getmp(pktin
);
5443 if (!s
->p
|| !s
->g
) {
5444 bombout(("unable to read mp-ints from incoming group packet"));
5447 ssh
->kex_ctx
= dh_setup_gex(s
->p
, s
->g
);
5448 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
5449 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
5451 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP
;
5452 ssh
->kex_ctx
= dh_setup_group(ssh
->kex
);
5453 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
5454 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
5455 logeventf(ssh
, "Using Diffie-Hellman with standard group \"%s\"",
5456 ssh
->kex
->groupname
);
5459 logevent("Doing Diffie-Hellman key exchange");
5461 * Now generate and send e for Diffie-Hellman.
5463 set_busy_status(ssh
->frontend
, BUSY_CPU
); /* this can take a while */
5464 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
5465 s
->pktout
= ssh2_pkt_init(s
->kex_init_value
);
5466 ssh2_pkt_addmp(s
->pktout
, s
->e
);
5467 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5469 set_busy_status(ssh
->frontend
, BUSY_WAITING
); /* wait for server */
5471 if (pktin
->type
!= s
->kex_reply_value
) {
5472 bombout(("expected key exchange reply packet from server"));
5475 set_busy_status(ssh
->frontend
, BUSY_CPU
); /* cogitate */
5476 ssh_pkt_getstring(pktin
, &s
->hostkeydata
, &s
->hostkeylen
);
5477 s
->f
= ssh2_pkt_getmp(pktin
);
5479 bombout(("unable to parse key exchange reply packet"));
5482 ssh_pkt_getstring(pktin
, &s
->sigdata
, &s
->siglen
);
5484 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
5486 /* We assume everything from now on will be quick, and it might
5487 * involve user interaction. */
5488 set_busy_status(ssh
->frontend
, BUSY_NOT
);
5490 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
5491 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5492 sha_uint32(&ssh
->exhash
, s
->pbits
);
5493 sha_mpint(&ssh
->exhash
, s
->p
);
5494 sha_mpint(&ssh
->exhash
, s
->g
);
5496 sha_mpint(&ssh
->exhash
, s
->e
);
5497 sha_mpint(&ssh
->exhash
, s
->f
);
5498 sha_mpint(&ssh
->exhash
, s
->K
);
5499 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
5501 dh_cleanup(ssh
->kex_ctx
);
5502 ssh
->kex_ctx
= NULL
;
5505 debug(("Exchange hash is:\n"));
5506 dmemdump(s
->exchange_hash
, 20);
5509 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
5511 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
5512 (char *)s
->exchange_hash
, 20)) {
5513 bombout(("Server's host key did not match the signature supplied"));
5518 * Authenticate remote host: verify host key. (We've already
5519 * checked the signature of the exchange hash.)
5521 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
5522 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
5523 ssh_set_frozen(ssh
, 1);
5524 s
->dlgret
= verify_ssh_host_key(ssh
->frontend
,
5525 ssh
->savedhost
, ssh
->savedport
,
5526 ssh
->hostkey
->keytype
, s
->keystr
,
5528 ssh_dialog_callback
, ssh
);
5529 if (s
->dlgret
< 0) {
5533 bombout(("Unexpected data from server while waiting"
5534 " for user host key response"));
5537 } while (pktin
|| inlen
> 0);
5538 s
->dlgret
= ssh
->user_response
;
5540 ssh_set_frozen(ssh
, 0);
5541 if (s
->dlgret
== 0) {
5542 ssh
->close_expected
= TRUE
;
5543 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5546 if (!s
->got_session_id
) { /* don't bother logging this in rekeys */
5547 logevent("Host key fingerprint is:");
5548 logevent(s
->fingerprint
);
5550 sfree(s
->fingerprint
);
5552 ssh
->hostkey
->freekey(s
->hkey
);
5555 * The exchange hash from the very first key exchange is also
5556 * the session id, used in session key construction and
5559 if (!s
->got_session_id
) {
5560 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
5561 sizeof(s
->exchange_hash
));
5562 s
->got_session_id
= TRUE
;
5566 * Send SSH2_MSG_NEWKEYS.
5568 s
->pktout
= ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
5569 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5570 ssh
->outgoing_data_size
= 0; /* start counting from here */
5573 * We've sent client NEWKEYS, so create and initialise
5574 * client-to-server session keys.
5576 if (ssh
->cs_cipher_ctx
)
5577 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
5578 ssh
->cscipher
= s
->cscipher_tobe
;
5579 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
5581 if (ssh
->cs_mac_ctx
)
5582 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
5583 ssh
->csmac
= s
->csmac_tobe
;
5584 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
5586 if (ssh
->cs_comp_ctx
)
5587 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
5588 ssh
->cscomp
= s
->cscomp_tobe
;
5589 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
5592 * Set IVs on client-to-server keys. Here we use the exchange
5593 * hash from the _first_ key exchange.
5596 unsigned char keyspace
[40];
5597 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
5598 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
5599 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
5600 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
5601 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
5602 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
5605 logeventf(ssh
, "Initialised %.200s client->server encryption",
5606 ssh
->cscipher
->text_name
);
5607 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
5608 ssh
->csmac
->text_name
);
5609 if (ssh
->cscomp
->text_name
)
5610 logeventf(ssh
, "Initialised %s compression",
5611 ssh
->cscomp
->text_name
);
5614 * Now our end of the key exchange is complete, we can send all
5615 * our queued higher-layer packets.
5617 ssh
->queueing
= FALSE
;
5618 ssh2_pkt_queuesend(ssh
);
5621 * Expect SSH2_MSG_NEWKEYS from server.
5624 if (pktin
->type
!= SSH2_MSG_NEWKEYS
) {
5625 bombout(("expected new-keys packet from server"));
5628 ssh
->incoming_data_size
= 0; /* start counting from here */
5631 * We've seen server NEWKEYS, so create and initialise
5632 * server-to-client session keys.
5634 if (ssh
->sc_cipher_ctx
)
5635 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
5636 ssh
->sccipher
= s
->sccipher_tobe
;
5637 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
5639 if (ssh
->sc_mac_ctx
)
5640 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
5641 ssh
->scmac
= s
->scmac_tobe
;
5642 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
5644 if (ssh
->sc_comp_ctx
)
5645 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
5646 ssh
->sccomp
= s
->sccomp_tobe
;
5647 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
5650 * Set IVs on server-to-client keys. Here we use the exchange
5651 * hash from the _first_ key exchange.
5654 unsigned char keyspace
[40];
5655 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
5656 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
5657 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
5658 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
5659 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
5660 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
5662 logeventf(ssh
, "Initialised %.200s server->client encryption",
5663 ssh
->sccipher
->text_name
);
5664 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
5665 ssh
->scmac
->text_name
);
5666 if (ssh
->sccomp
->text_name
)
5667 logeventf(ssh
, "Initialised %s decompression",
5668 ssh
->sccomp
->text_name
);
5671 * Free key exchange data.
5675 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5681 * Key exchange is over. Loop straight back round if we have a
5682 * deferred rekey reason.
5684 if (ssh
->deferred_rekey_reason
) {
5685 logevent(ssh
->deferred_rekey_reason
);
5687 ssh
->deferred_rekey_reason
= NULL
;
5688 goto begin_key_exchange
;
5692 * Otherwise, schedule a timer for our next rekey.
5694 ssh
->kex_in_progress
= FALSE
;
5695 ssh
->last_rekey
= GETTICKCOUNT();
5696 if (ssh
->cfg
.ssh_rekey_time
!= 0)
5697 ssh
->next_rekey
= schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5701 * If this is the first key exchange phase, we must pass the
5702 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5703 * wants to see it but because it will need time to initialise
5704 * itself before it sees an actual packet. In subsequent key
5705 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5706 * it would only confuse the layer above.
5708 if (s
->activated_authconn
) {
5711 s
->activated_authconn
= TRUE
;
5714 * Now we're encrypting. Begin returning 1 to the protocol main
5715 * function so that other things can run on top of the
5716 * transport. If we ever see a KEXINIT, we must go back to the
5719 * We _also_ go back to the start if we see pktin==NULL and
5720 * inlen==-1, because this is a special signal meaning
5721 * `initiate client-driven rekey', and `in' contains a message
5722 * giving the reason for the rekey.
5724 while (!((pktin
&& pktin
->type
== SSH2_MSG_KEXINIT
) ||
5725 (!pktin
&& inlen
== -1))) {
5730 logevent("Server initiated key re-exchange");
5733 * Special case: if the server bug is set that doesn't
5734 * allow rekeying, we give a different log message and
5735 * continue waiting. (If such a server _initiates_ a rekey,
5736 * we process it anyway!)
5738 if ((ssh
->remote_bugs
& BUG_SSH2_REKEY
)) {
5739 logeventf(ssh
, "Server bug prevents key re-exchange (%s)",
5741 /* Reset the counters, so that at least this message doesn't
5742 * hit the event log _too_ often. */
5743 ssh
->outgoing_data_size
= 0;
5744 ssh
->incoming_data_size
= 0;
5745 if (ssh
->cfg
.ssh_rekey_time
!= 0) {
5747 schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5750 goto wait_for_rekey
; /* this is utterly horrid */
5752 logeventf(ssh
, "Initiating key re-exchange (%s)", (char *)in
);
5755 goto begin_key_exchange
;
5761 * Add data to an SSH-2 channel output buffer.
5763 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
5766 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
5770 * Attempt to send data on an SSH-2 channel.
5772 static int ssh2_try_send(struct ssh_channel
*c
)
5775 struct Packet
*pktout
;
5777 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
5780 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
5781 if ((unsigned)len
> c
->v
.v2
.remwindow
)
5782 len
= c
->v
.v2
.remwindow
;
5783 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
5784 len
= c
->v
.v2
.remmaxpkt
;
5785 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
5786 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5787 dont_log_data(ssh
, pktout
, PKTLOG_OMIT
);
5788 ssh2_pkt_addstring_start(pktout
);
5789 ssh2_pkt_addstring_data(pktout
, data
, len
);
5790 end_log_omission(ssh
, pktout
);
5791 ssh2_pkt_send(ssh
, pktout
);
5792 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
5793 c
->v
.v2
.remwindow
-= len
;
5797 * After having sent as much data as we can, return the amount
5800 return bufchain_size(&c
->v
.v2
.outbuffer
);
5803 static void ssh2_try_send_and_unthrottle(struct ssh_channel
*c
)
5807 return; /* don't send on closing channels */
5808 bufsize
= ssh2_try_send(c
);
5811 case CHAN_MAINSESSION
:
5812 /* stdin need not receive an unthrottle
5813 * notification since it will be polled */
5816 x11_unthrottle(c
->u
.x11
.s
);
5819 /* agent sockets are request/response and need no
5820 * buffer management */
5823 pfd_unthrottle(c
->u
.pfd
.s
);
5830 * Potentially enlarge the window on an SSH-2 channel.
5832 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
5837 * Never send WINDOW_ADJUST for a channel that the remote side
5838 * already thinks it's closed; there's no point, since it won't
5839 * be sending any more data anyway.
5845 * Only send a WINDOW_ADJUST if there's significantly more window
5846 * available than the other end thinks there is. This saves us
5847 * sending a WINDOW_ADJUST for every character in a shell session.
5849 * "Significant" is arbitrarily defined as half the window size.
5851 if (newwin
> c
->v
.v2
.locwindow
* 2) {
5852 struct Packet
*pktout
;
5854 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5855 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5856 ssh2_pkt_adduint32(pktout
, newwin
- c
->v
.v2
.locwindow
);
5857 ssh2_pkt_send(ssh
, pktout
);
5858 c
->v
.v2
.locwindow
= newwin
;
5862 static void ssh2_msg_channel_window_adjust(Ssh ssh
, struct Packet
*pktin
)
5864 unsigned i
= ssh_pkt_getuint32(pktin
);
5865 struct ssh_channel
*c
;
5866 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5867 if (c
&& !c
->closes
) {
5868 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
5869 ssh2_try_send_and_unthrottle(c
);
5873 static void ssh2_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
5877 unsigned i
= ssh_pkt_getuint32(pktin
);
5878 struct ssh_channel
*c
;
5879 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5881 return; /* nonexistent channel */
5882 if (pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5883 ssh_pkt_getuint32(pktin
) != SSH2_EXTENDED_DATA_STDERR
)
5884 return; /* extended but not stderr */
5885 ssh_pkt_getstring(pktin
, &data
, &length
);
5888 c
->v
.v2
.locwindow
-= length
;
5890 case CHAN_MAINSESSION
:
5892 from_backend(ssh
->frontend
, pktin
->type
==
5893 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5897 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5900 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5903 while (length
> 0) {
5904 if (c
->u
.a
.lensofar
< 4) {
5905 unsigned int l
= min(4 - c
->u
.a
.lensofar
, length
);
5906 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5910 c
->u
.a
.lensofar
+= l
;
5912 if (c
->u
.a
.lensofar
== 4) {
5914 4 + GET_32BIT(c
->u
.a
.msglen
);
5915 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
5917 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5919 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5921 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5923 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5927 c
->u
.a
.lensofar
+= l
;
5929 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5932 if (agent_query(c
->u
.a
.message
,
5935 ssh_agentf_callback
, c
))
5936 ssh_agentf_callback(c
, reply
, replylen
);
5937 sfree(c
->u
.a
.message
);
5938 c
->u
.a
.lensofar
= 0;
5945 * If we are not buffering too much data,
5946 * enlarge the window again at the remote side.
5948 if (bufsize
< OUR_V2_WINSIZE
)
5949 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5953 static void ssh2_msg_channel_eof(Ssh ssh
, struct Packet
*pktin
)
5955 unsigned i
= ssh_pkt_getuint32(pktin
);
5956 struct ssh_channel
*c
;
5958 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5960 return; /* nonexistent channel */
5962 if (c
->type
== CHAN_X11
) {
5964 * Remote EOF on an X11 channel means we should
5965 * wrap up and close the channel ourselves.
5967 x11_close(c
->u
.x11
.s
);
5969 } else if (c
->type
== CHAN_AGENT
) {
5971 } else if (c
->type
== CHAN_SOCKDATA
) {
5972 pfd_close(c
->u
.pfd
.s
);
5977 static void ssh2_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
5979 unsigned i
= ssh_pkt_getuint32(pktin
);
5980 struct ssh_channel
*c
;
5981 struct Packet
*pktout
;
5983 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5984 if (!c
|| c
->halfopen
) {
5985 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5986 c ?
"half-open" : "nonexistent", i
));
5989 /* Do pre-close processing on the channel. */
5991 case CHAN_MAINSESSION
:
5992 ssh
->mainchan
= NULL
;
5993 update_specials_menu(ssh
->frontend
);
5996 if (c
->u
.x11
.s
!= NULL
)
5997 x11_close(c
->u
.x11
.s
);
6004 if (c
->u
.pfd
.s
!= NULL
)
6005 pfd_close(c
->u
.pfd
.s
);
6009 if (c
->closes
== 0) {
6010 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
6011 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6012 ssh2_pkt_send(ssh
, pktout
);
6014 del234(ssh
->channels
, c
);
6015 bufchain_clear(&c
->v
.v2
.outbuffer
);
6019 * See if that was the last channel left open.
6020 * (This is only our termination condition if we're
6021 * not running in -N mode.)
6023 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
6024 logevent("All channels closed. Disconnecting");
6027 * We used to send SSH_MSG_DISCONNECT here,
6028 * because I'd believed that _every_ conforming
6029 * SSH-2 connection had to end with a disconnect
6030 * being sent by at least one side; apparently
6031 * I was wrong and it's perfectly OK to
6032 * unceremoniously slam the connection shut
6033 * when you're done, and indeed OpenSSH feels
6034 * this is more polite than sending a
6035 * DISCONNECT. So now we don't.
6037 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6038 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
6039 ssh2_pkt_addstring(s
->pktout
, "All open channels closed");
6040 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6041 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6043 ssh
->close_expected
= TRUE
;
6044 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6048 static void ssh2_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
6050 unsigned i
= ssh_pkt_getuint32(pktin
);
6051 struct ssh_channel
*c
;
6052 struct Packet
*pktout
;
6054 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6056 return; /* nonexistent channel */
6057 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
6058 return; /* dunno why they're confirming this */
6059 c
->remoteid
= ssh_pkt_getuint32(pktin
);
6060 c
->halfopen
= FALSE
;
6061 c
->type
= CHAN_SOCKDATA
;
6062 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
6063 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
6065 pfd_confirm(c
->u
.pfd
.s
);
6068 * We have a pending close on this channel,
6069 * which we decided on before the server acked
6070 * the channel open. So now we know the
6071 * remoteid, we can close it again.
6073 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
6074 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6075 ssh2_pkt_send(ssh
, pktout
);
6079 static void ssh2_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
6081 static const char *const reasons
[] = {
6082 "<unknown reason code>",
6083 "Administratively prohibited",
6085 "Unknown channel type",
6086 "Resource shortage",
6088 unsigned i
= ssh_pkt_getuint32(pktin
);
6089 unsigned reason_code
;
6090 char *reason_string
;
6092 struct ssh_channel
*c
;
6093 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6095 return; /* nonexistent channel */
6096 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
6097 return; /* dunno why they're failing this */
6099 reason_code
= ssh_pkt_getuint32(pktin
);
6100 if (reason_code
>= lenof(reasons
))
6101 reason_code
= 0; /* ensure reasons[reason_code] in range */
6102 ssh_pkt_getstring(pktin
, &reason_string
, &reason_length
);
6103 logeventf(ssh
, "Forwarded connection refused by server: %s [%.*s]",
6104 reasons
[reason_code
], reason_length
, reason_string
);
6106 pfd_close(c
->u
.pfd
.s
);
6108 del234(ssh
->channels
, c
);
6112 static void ssh2_msg_channel_request(Ssh ssh
, struct Packet
*pktin
)
6116 int typelen
, want_reply
;
6117 int reply
= SSH2_MSG_CHANNEL_FAILURE
; /* default */
6118 struct ssh_channel
*c
;
6119 struct Packet
*pktout
;
6121 localid
= ssh_pkt_getuint32(pktin
);
6122 ssh_pkt_getstring(pktin
, &type
, &typelen
);
6123 want_reply
= ssh2_pkt_getbool(pktin
);
6126 * First, check that the channel exists. Otherwise,
6127 * we can instantly disconnect with a rude message.
6129 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
6132 sprintf(buf
, "Received channel request for nonexistent"
6133 " channel %d", localid
);
6135 pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6136 ssh2_pkt_adduint32(pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
6137 ssh2_pkt_addstring(pktout
, buf
);
6138 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
6139 ssh2_pkt_send_noqueue(ssh
, pktout
);
6140 connection_fatal(ssh
->frontend
, "%s", buf
);
6141 ssh
->close_expected
= TRUE
;
6142 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6147 * Having got the channel number, we now look at
6148 * the request type string to see if it's something
6151 if (c
== ssh
->mainchan
) {
6153 * We recognise "exit-status" and "exit-signal" on
6154 * the primary channel.
6156 if (typelen
== 11 &&
6157 !memcmp(type
, "exit-status", 11)) {
6159 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
6160 logeventf(ssh
, "Server sent command exit status %d",
6162 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
6164 } else if (typelen
== 11 &&
6165 !memcmp(type
, "exit-signal", 11)) {
6167 int is_plausible
= TRUE
, is_int
= FALSE
;
6168 char *fmt_sig
= "", *fmt_msg
= "";
6170 int msglen
= 0, core
= FALSE
;
6171 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
6172 * provide an `int' for the signal, despite its
6173 * having been a `string' in the drafts since at
6174 * least 2001. (Fixed in session.c 1.147.) Try to
6175 * infer which we can safely parse it as. */
6177 unsigned char *p
= pktin
->body
+
6179 long len
= pktin
->length
- pktin
->savedpos
;
6180 unsigned long num
= GET_32BIT(p
); /* what is it? */
6181 /* If it's 0, it hardly matters; assume string */
6185 int maybe_int
= FALSE
, maybe_str
= FALSE
;
6186 #define CHECK_HYPOTHESIS(offset, result) \
6189 if (q >= 0 && q+4 <= len) { \
6190 q = q + 4 + GET_32BIT(p+q); \
6191 if (q >= 0 && q+4 <= len && \
6192 ((q = q + 4 + GET_32BIT(p+q))!= 0) && q == len) \
6196 CHECK_HYPOTHESIS(4+1, maybe_int
);
6197 CHECK_HYPOTHESIS(4+num
+1, maybe_str
);
6198 #undef CHECK_HYPOTHESIS
6199 if (maybe_int
&& !maybe_str
)
6201 else if (!maybe_int
&& maybe_str
)
6204 /* Crikey. Either or neither. Panic. */
6205 is_plausible
= FALSE
;
6210 /* Old non-standard OpenSSH. */
6211 int signum
= ssh_pkt_getuint32(pktin
);
6212 fmt_sig
= dupprintf(" %d", signum
);
6214 /* As per the drafts. */
6217 ssh_pkt_getstring(pktin
, &sig
, &siglen
);
6218 /* Signal name isn't supposed to be blank, but
6219 * let's cope gracefully if it is. */
6221 fmt_sig
= dupprintf(" \"%.*s\"",
6225 core
= ssh2_pkt_getbool(pktin
);
6226 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
6228 fmt_msg
= dupprintf(" (\"%.*s\")", msglen
, msg
);
6230 /* ignore lang tag */
6231 } /* else don't attempt to parse */
6232 logeventf(ssh
, "Server exited on signal%s%s%s",
6233 fmt_sig
, core ?
" (core dumped)" : "",
6235 if (*fmt_sig
) sfree(fmt_sig
);
6236 if (*fmt_msg
) sfree(fmt_msg
);
6237 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
6242 * This is a channel request we don't know
6243 * about, so we now either ignore the request
6244 * or respond with CHANNEL_FAILURE, depending
6247 reply
= SSH2_MSG_CHANNEL_FAILURE
;
6250 pktout
= ssh2_pkt_init(reply
);
6251 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6252 ssh2_pkt_send(ssh
, pktout
);
6256 static void ssh2_msg_global_request(Ssh ssh
, struct Packet
*pktin
)
6259 int typelen
, want_reply
;
6260 struct Packet
*pktout
;
6262 ssh_pkt_getstring(pktin
, &type
, &typelen
);
6263 want_reply
= ssh2_pkt_getbool(pktin
);
6266 * We currently don't support any global requests
6267 * at all, so we either ignore the request or
6268 * respond with REQUEST_FAILURE, depending on
6272 pktout
= ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
6273 ssh2_pkt_send(ssh
, pktout
);
6277 static void ssh2_msg_channel_open(Ssh ssh
, struct Packet
*pktin
)
6285 struct ssh_channel
*c
;
6286 unsigned remid
, winsize
, pktsize
;
6287 struct Packet
*pktout
;
6289 ssh_pkt_getstring(pktin
, &type
, &typelen
);
6290 c
= snew(struct ssh_channel
);
6293 remid
= ssh_pkt_getuint32(pktin
);
6294 winsize
= ssh_pkt_getuint32(pktin
);
6295 pktsize
= ssh_pkt_getuint32(pktin
);
6297 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
6300 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
6301 addrstr
= snewn(peeraddrlen
+1, char);
6302 memcpy(addrstr
, peeraddr
, peeraddrlen
);
6303 addrstr
[peeraddrlen
] = '\0';
6304 peerport
= ssh_pkt_getuint32(pktin
);
6306 logeventf(ssh
, "Received X11 connect request from %s:%d",
6309 if (!ssh
->X11_fwd_enabled
)
6310 error
= "X11 forwarding is not enabled";
6311 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
6312 ssh
->x11auth
, addrstr
, peerport
,
6313 &ssh
->cfg
) != NULL
) {
6314 error
= "Unable to open an X11 connection";
6316 logevent("Opening X11 forward connection succeeded");
6321 } else if (typelen
== 15 &&
6322 !memcmp(type
, "forwarded-tcpip", 15)) {
6323 struct ssh_rportfwd pf
, *realpf
;
6326 ssh_pkt_getstring(pktin
, &dummy
, &dummylen
);/* skip address */
6327 pf
.sport
= ssh_pkt_getuint32(pktin
);
6328 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
6329 peerport
= ssh_pkt_getuint32(pktin
);
6330 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
6331 logeventf(ssh
, "Received remote port %d open request "
6332 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
6333 if (realpf
== NULL
) {
6334 error
= "Remote port is not recognised";
6336 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
6340 realpf
->pfrec
->addressfamily
);
6341 logeventf(ssh
, "Attempting to forward remote port to "
6342 "%s:%d", realpf
->dhost
, realpf
->dport
);
6344 logeventf(ssh
, "Port open failed: %s", e
);
6345 error
= "Port open failed";
6347 logevent("Forwarded port opened successfully");
6348 c
->type
= CHAN_SOCKDATA
;
6351 } else if (typelen
== 22 &&
6352 !memcmp(type
, "auth-agent@openssh.com", 3)) {
6353 if (!ssh
->agentfwd_enabled
)
6354 error
= "Agent forwarding is not enabled";
6356 c
->type
= CHAN_AGENT
; /* identify channel type */
6357 c
->u
.a
.lensofar
= 0;
6360 error
= "Unsupported channel type requested";
6363 c
->remoteid
= remid
;
6364 c
->halfopen
= FALSE
;
6366 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
6367 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6368 ssh2_pkt_adduint32(pktout
, SSH2_OPEN_CONNECT_FAILED
);
6369 ssh2_pkt_addstring(pktout
, error
);
6370 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
6371 ssh2_pkt_send(ssh
, pktout
);
6372 logeventf(ssh
, "Rejected channel open: %s", error
);
6375 c
->localid
= alloc_channel_id(ssh
);
6377 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6378 c
->v
.v2
.remwindow
= winsize
;
6379 c
->v
.v2
.remmaxpkt
= pktsize
;
6380 bufchain_init(&c
->v
.v2
.outbuffer
);
6381 add234(ssh
->channels
, c
);
6382 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
6383 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6384 ssh2_pkt_adduint32(pktout
, c
->localid
);
6385 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);
6386 ssh2_pkt_adduint32(pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
6387 ssh2_pkt_send(ssh
, pktout
);
6392 * Buffer banner messages for later display at some convenient point.
6394 static void ssh2_msg_userauth_banner(Ssh ssh
, struct Packet
*pktin
)
6396 /* Arbitrary limit to prevent unbounded inflation of buffer */
6397 if (bufchain_size(&ssh
->banner
) <= 131072) {
6398 char *banner
= NULL
;
6400 ssh_pkt_getstring(pktin
, &banner
, &size
);
6402 bufchain_add(&ssh
->banner
, banner
, size
);
6406 /* Helper function to deal with sending tty modes for "pty-req" */
6407 static void ssh2_send_ttymode(void *data
, char *mode
, char *val
)
6409 struct Packet
*pktout
= (struct Packet
*)data
;
6411 unsigned int arg
= 0;
6412 while (strcmp(mode
, ssh_ttymodes
[i
].mode
) != 0) i
++;
6413 if (i
== lenof(ssh_ttymodes
)) return;
6414 switch (ssh_ttymodes
[i
].type
) {
6416 arg
= ssh_tty_parse_specchar(val
);
6419 arg
= ssh_tty_parse_boolean(val
);
6422 ssh2_pkt_addbyte(pktout
, ssh_ttymodes
[i
].opcode
);
6423 ssh2_pkt_adduint32(pktout
, arg
);
6427 * Handle the SSH-2 userauth and connection layers.
6429 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
6430 struct Packet
*pktin
)
6432 struct do_ssh2_authconn_state
{
6434 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
6436 AUTH_KEYBOARD_INTERACTIVE
6440 AUTH_TYPE_PUBLICKEY
,
6441 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
6442 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
6444 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
6445 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
6447 int done_service_req
;
6448 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
6449 int tried_pubkey_config
, tried_agent
;
6450 int kbd_inter_running
, kbd_inter_refused
;
6452 int num_prompts
, curr_prompt
, echo
;
6457 void *publickey_blob
;
6458 int publickey_bloblen
;
6459 unsigned char request
[5], *response
, *p
;
6463 char *pkblob
, *alg
, *commentp
;
6464 int pklen
, alglen
, commentlen
;
6465 int siglen
, retlen
, len
;
6466 char *q
, *agentreq
, *ret
;
6468 int num_env
, env_left
, env_ok
;
6469 struct Packet
*pktout
;
6471 crState(do_ssh2_authconn_state
);
6473 crBegin(ssh
->do_ssh2_authconn_crstate
);
6475 s
->done_service_req
= FALSE
;
6476 s
->we_are_in
= FALSE
;
6477 if (!ssh
->cfg
.ssh_no_userauth
) {
6479 * Request userauth protocol, and await a response to it.
6481 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
6482 ssh2_pkt_addstring(s
->pktout
, "ssh-userauth");
6483 ssh2_pkt_send(ssh
, s
->pktout
);
6484 crWaitUntilV(pktin
);
6485 if (pktin
->type
== SSH2_MSG_SERVICE_ACCEPT
)
6486 s
->done_service_req
= TRUE
;
6488 if (!s
->done_service_req
) {
6490 * Request connection protocol directly, without authentication.
6492 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
6493 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");
6494 ssh2_pkt_send(ssh
, s
->pktout
);
6495 crWaitUntilV(pktin
);
6496 if (pktin
->type
== SSH2_MSG_SERVICE_ACCEPT
) {
6497 s
->we_are_in
= TRUE
; /* no auth required */
6499 bombout(("Server refused service request"));
6505 * We repeat this whole loop, including the username prompt,
6506 * until we manage a successful authentication. If the user
6507 * types the wrong _password_, they can be sent back to the
6508 * beginning to try another username, if this is configured on.
6509 * (If they specify a username in the config, they are never
6510 * asked, even if they do give a wrong password.)
6512 * I think this best serves the needs of
6514 * - the people who have no configuration, no keys, and just
6515 * want to try repeated (username,password) pairs until they
6516 * type both correctly
6518 * - people who have keys and configuration but occasionally
6519 * need to fall back to passwords
6521 * - people with a key held in Pageant, who might not have
6522 * logged in to a particular machine before; so they want to
6523 * type a username, and then _either_ their key will be
6524 * accepted, _or_ they will type a password. If they mistype
6525 * the username they will want to be able to get back and
6528 s
->username
[0] = '\0';
6529 s
->got_username
= FALSE
;
6530 bufchain_init(&ssh
->banner
);
6531 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] =
6532 ssh2_msg_userauth_banner
;
6533 while (!s
->we_are_in
) {
6537 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
6539 * We got a username last time round this loop, and
6540 * with change_username turned off we don't try to get
6543 } else if (!*ssh
->cfg
.username
) {
6544 if (ssh_get_line
&& !ssh_getline_pw_only
) {
6545 if (!ssh_get_line("login as: ",
6546 s
->username
, sizeof(s
->username
), FALSE
)) {
6548 * get_line failed to get a username.
6551 logevent("No username provided. Abandoning session.");
6552 ssh
->close_expected
= TRUE
;
6553 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6557 int ret
; /* need not be saved across crReturn */
6558 c_write_str(ssh
, "login as: ");
6560 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
6562 crWaitUntilV(!pktin
);
6563 ret
= process_userpass_input(ssh
, in
, inlen
);
6567 c_write_str(ssh
, "\r\n");
6569 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
6572 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
6573 s
->username
[sizeof(s
->username
)-1] = '\0';
6574 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
6575 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
6576 c_write_str(ssh
, stuff
);
6580 s
->got_username
= TRUE
;
6583 * Send an authentication request using method "none": (a)
6584 * just in case it succeeds, and (b) so that we know what
6585 * authentication methods we can usefully try next.
6587 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6589 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6590 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6591 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");/* service requested */
6592 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6593 ssh2_pkt_send(ssh
, s
->pktout
);
6594 s
->type
= AUTH_TYPE_NONE
;
6596 s
->we_are_in
= FALSE
;
6598 s
->tried_pubkey_config
= FALSE
;
6599 s
->tried_agent
= FALSE
;
6600 s
->kbd_inter_running
= FALSE
;
6601 s
->kbd_inter_refused
= FALSE
;
6602 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
6603 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
6605 logeventf(ssh
, "Reading private key file \"%.150s\"",
6606 filename_to_str(&ssh
->cfg
.keyfile
));
6607 keytype
= key_type(&ssh
->cfg
.keyfile
);
6608 if (keytype
== SSH_KEYTYPE_SSH2
) {
6610 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
6611 &s
->publickey_bloblen
, NULL
);
6614 logeventf(ssh
, "Unable to use this key file (%s)",
6615 key_type_to_str(keytype
));
6616 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
6618 filename_to_str(&ssh
->cfg
.keyfile
),
6619 key_type_to_str(keytype
));
6620 c_write_str(ssh
, msgbuf
);
6622 s
->publickey_blob
= NULL
;
6625 s
->publickey_blob
= NULL
;
6629 * Wait for the result of the last authentication request.
6632 crWaitUntilV(pktin
);
6634 * Now is a convenient point to spew any banner material
6635 * that we've accumulated. (This should ensure that when
6636 * we exit the auth loop, we haven't any left to deal
6640 int size
= bufchain_size(&ssh
->banner
);
6642 * Don't show the banner if we're operating in
6643 * non-verbose non-interactive mode. (It's probably
6644 * a script, which means nobody will read the
6645 * banner _anyway_, and moreover the printing of
6646 * the banner will screw up processing on the
6647 * output of (say) plink.)
6649 if (size
&& (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
))) {
6650 char *banner
= snewn(size
, char);
6651 bufchain_fetch(&ssh
->banner
, banner
, size
);
6652 c_write_untrusted(ssh
, banner
, size
);
6655 bufchain_clear(&ssh
->banner
);
6657 if (pktin
->type
== SSH2_MSG_USERAUTH_SUCCESS
) {
6658 logevent("Access granted");
6659 s
->we_are_in
= TRUE
;
6663 if (s
->kbd_inter_running
&&
6664 pktin
->type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6666 * This is either a further set-of-prompts packet
6667 * in keyboard-interactive authentication, or it's
6668 * the same one and we came back here with `gotit'
6669 * set. In the former case, we must reset the
6670 * curr_prompt variable.
6674 } else if (pktin
->type
== SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
) {
6675 /* FIXME: perhaps we should support this? */
6676 bombout(("PASSWD_CHANGEREQ not yet supported"));
6678 } else if (pktin
->type
!= SSH2_MSG_USERAUTH_FAILURE
) {
6679 bombout(("Strange packet received during authentication: type %d",
6687 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6688 * we can look at the string in it and know what we can
6689 * helpfully try next.
6691 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
) {
6694 ssh_pkt_getstring(pktin
, &methods
, &methlen
);
6695 s
->kbd_inter_running
= FALSE
;
6696 if (!ssh2_pkt_getbool(pktin
)) {
6698 * We have received an unequivocal Access
6699 * Denied. This can translate to a variety of
6702 * - if we'd just tried "none" authentication,
6703 * it's not worth printing anything at all
6705 * - if we'd just tried a public key _offer_,
6706 * the message should be "Server refused our
6707 * key" (or no message at all if the key
6708 * came from Pageant)
6710 * - if we'd just tried anything else, the
6711 * message really should be "Access denied".
6713 * Additionally, if we'd just tried password
6714 * authentication, we should break out of this
6715 * whole loop so as to go back to the username
6716 * prompt (iff we're configured to allow
6717 * username change attempts).
6719 if (s
->type
== AUTH_TYPE_NONE
) {
6721 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
6722 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
6723 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
6724 c_write_str(ssh
, "Server refused our key\r\n");
6725 logevent("Server refused public key");
6726 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
6727 /* server declined keyboard-interactive; ignore */
6729 c_write_str(ssh
, "Access denied\r\n");
6730 logevent("Access denied");
6731 if (s
->type
== AUTH_TYPE_PASSWORD
&&
6732 ssh
->cfg
.change_username
) {
6733 /* XXX perhaps we should allow
6734 * keyboard-interactive to do this too? */
6735 s
->we_are_in
= FALSE
;
6740 c_write_str(ssh
, "Further authentication required\r\n");
6741 logevent("Further authentication required");
6745 in_commasep_string("publickey", methods
, methlen
);
6747 in_commasep_string("password", methods
, methlen
);
6748 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
6749 in_commasep_string("keyboard-interactive", methods
, methlen
);
6753 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6757 * Most password/passphrase prompts will be
6758 * non-echoing, so we set this to 0 by default.
6759 * Exception is that some keyboard-interactive prompts
6760 * can be echoing, in which case we'll set this to 1.
6764 if (!s
->method
&& s
->can_pubkey
&&
6765 agent_exists() && !s
->tried_agent
) {
6767 * Attempt public-key authentication using Pageant.
6772 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6773 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6775 s
->tried_agent
= TRUE
;
6777 logevent("Pageant is running. Requesting keys.");
6779 /* Request the keys held by the agent. */
6780 PUT_32BIT(s
->request
, 1);
6781 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
6782 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
6783 ssh_agent_callback
, ssh
)) {
6787 bombout(("Unexpected data from server while"
6788 " waiting for agent response"));
6791 } while (pktin
|| inlen
> 0);
6792 r
= ssh
->agent_response
;
6793 s
->responselen
= ssh
->agent_response_len
;
6795 s
->response
= (unsigned char *) r
;
6796 if (s
->response
&& s
->responselen
>= 5 &&
6797 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
6798 s
->p
= s
->response
+ 5;
6799 s
->nkeys
= GET_32BIT(s
->p
);
6801 logeventf(ssh
, "Pageant has %d SSH-2 keys", s
->nkeys
);
6802 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
6805 logeventf(ssh
, "Trying Pageant key #%d", s
->keyi
);
6806 s
->pklen
= GET_32BIT(s
->p
);
6808 if (s
->publickey_blob
&&
6809 s
->pklen
== s
->publickey_bloblen
&&
6810 !memcmp(s
->p
, s
->publickey_blob
,
6811 s
->publickey_bloblen
)) {
6812 logevent("This key matches configured key file");
6813 s
->tried_pubkey_config
= 1;
6815 s
->pkblob
= (char *)s
->p
;
6817 s
->alglen
= GET_32BIT(s
->pkblob
);
6818 s
->alg
= s
->pkblob
+ 4;
6819 s
->commentlen
= GET_32BIT(s
->p
);
6821 s
->commentp
= (char *)s
->p
;
6822 s
->p
+= s
->commentlen
;
6823 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6824 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6825 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6826 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6827 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6828 ssh2_pkt_addstring_start(s
->pktout
);
6829 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6830 ssh2_pkt_addstring_start(s
->pktout
);
6831 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6832 ssh2_pkt_send(ssh
, s
->pktout
);
6834 crWaitUntilV(pktin
);
6835 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6836 logevent("Key refused");
6840 if (flags
& FLAG_VERBOSE
) {
6841 c_write_str(ssh
, "Authenticating with "
6843 c_write(ssh
, s
->commentp
, s
->commentlen
);
6844 c_write_str(ssh
, "\" from agent\r\n");
6848 * Server is willing to accept the key.
6849 * Construct a SIGN_REQUEST.
6851 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6852 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6853 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6854 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6855 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6856 ssh2_pkt_addstring_start(s
->pktout
);
6857 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6858 ssh2_pkt_addstring_start(s
->pktout
);
6859 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6861 s
->siglen
= s
->pktout
->length
- 5 + 4 + 20;
6862 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6864 s
->len
= 1; /* message type */
6865 s
->len
+= 4 + s
->pklen
; /* key blob */
6866 s
->len
+= 4 + s
->siglen
; /* data to sign */
6867 s
->len
+= 4; /* flags */
6868 s
->agentreq
= snewn(4 + s
->len
, char);
6869 PUT_32BIT(s
->agentreq
, s
->len
);
6870 s
->q
= s
->agentreq
+ 4;
6871 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
6872 PUT_32BIT(s
->q
, s
->pklen
);
6874 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
6876 PUT_32BIT(s
->q
, s
->siglen
);
6878 /* Now the data to be signed... */
6879 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6880 PUT_32BIT(s
->q
, 20);
6883 memcpy(s
->q
, ssh
->v2_session_id
, 20);
6885 memcpy(s
->q
, s
->pktout
->data
+ 5,
6886 s
->pktout
->length
- 5);
6887 s
->q
+= s
->pktout
->length
- 5;
6888 /* And finally the (zero) flags word. */
6890 if (!agent_query(s
->agentreq
, s
->len
+ 4,
6892 ssh_agent_callback
, ssh
)) {
6896 bombout(("Unexpected data from server"
6897 " while waiting for agent"
6901 } while (pktin
|| inlen
> 0);
6902 vret
= ssh
->agent_response
;
6903 s
->retlen
= ssh
->agent_response_len
;
6908 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
6909 logevent("Sending Pageant's response");
6910 ssh2_add_sigblob(ssh
, s
->pktout
,
6911 s
->pkblob
, s
->pklen
,
6913 GET_32BIT(s
->ret
+ 5));
6914 ssh2_pkt_send(ssh
, s
->pktout
);
6919 ("Pageant failed to answer challenge");
6930 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
6931 && !s
->tried_pubkey_config
) {
6932 unsigned char *pub_blob
;
6933 char *algorithm
, *comment
;
6936 s
->tried_pubkey_config
= TRUE
;
6938 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6939 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6942 * Try the public key supplied in the configuration.
6944 * First, offer the public blob to see if the server is
6945 * willing to accept it.
6948 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
6953 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6954 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6955 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6956 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6957 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6958 ssh2_pkt_addstring(s
->pktout
, algorithm
);
6959 ssh2_pkt_addstring_start(s
->pktout
);
6960 ssh2_pkt_addstring_data(s
->pktout
, (char *)pub_blob
,
6962 ssh2_pkt_send(ssh
, s
->pktout
);
6963 logevent("Offered public key");
6965 crWaitUntilV(pktin
);
6966 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6968 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
6969 continue; /* key refused; give up on it */
6972 logevent("Offer of public key accepted");
6974 * Actually attempt a serious authentication using
6977 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
6978 sprintf(s
->pwprompt
,
6979 "Passphrase for key \"%.100s\": ",
6985 if (flags
& FLAG_VERBOSE
) {
6986 c_write_str(ssh
, "Authenticating with public key \"");
6987 c_write_str(ssh
, comment
);
6988 c_write_str(ssh
, "\"\r\n");
6990 s
->method
= AUTH_PUBLICKEY_FILE
;
6994 if (!s
->method
&& s
->can_keyb_inter
&& !s
->kbd_inter_refused
&&
6995 !s
->kbd_inter_running
) {
6996 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6997 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6999 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
7000 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
7002 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
7003 ssh2_pkt_addstring(s
->pktout
, s
->username
);
7004 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
7005 ssh2_pkt_addstring(s
->pktout
, "keyboard-interactive"); /* method */
7006 ssh2_pkt_addstring(s
->pktout
, ""); /* lang */
7007 ssh2_pkt_addstring(s
->pktout
, "");
7008 ssh2_pkt_send(ssh
, s
->pktout
);
7010 crWaitUntilV(pktin
);
7011 if (pktin
->type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
7012 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
)
7014 logevent("Keyboard-interactive authentication refused");
7015 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
7016 s
->kbd_inter_refused
= TRUE
; /* don't try it again */
7020 c_write_str(ssh
, "Using keyboard-interactive authentication.\r\n");
7021 s
->kbd_inter_running
= TRUE
;
7025 if (s
->kbd_inter_running
) {
7026 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
7027 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
7029 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
7030 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
7032 if (s
->curr_prompt
== 0) {
7034 * We've got a fresh USERAUTH_INFO_REQUEST.
7035 * Display header data, and start going through
7038 char *name
, *inst
, *lang
;
7039 int name_len
, inst_len
, lang_len
;
7041 ssh_pkt_getstring(pktin
, &name
, &name_len
);
7042 ssh_pkt_getstring(pktin
, &inst
, &inst_len
);
7043 ssh_pkt_getstring(pktin
, &lang
, &lang_len
);
7045 c_write_untrusted(ssh
, name
, name_len
);
7046 c_write_str(ssh
, "\r\n");
7049 c_write_untrusted(ssh
, inst
, inst_len
);
7050 c_write_str(ssh
, "\r\n");
7052 s
->num_prompts
= ssh_pkt_getuint32(pktin
);
7056 * If there are prompts remaining in the packet,
7057 * display one and get a response.
7059 if (s
->curr_prompt
< s
->num_prompts
) {
7063 ssh_pkt_getstring(pktin
, &prompt
, &prompt_len
);
7064 if (prompt_len
> 0) {
7065 static const char trunc
[] = "<prompt truncated>: ";
7066 static const int prlen
= sizeof(s
->pwprompt
) -
7068 if (prompt_len
> prlen
) {
7069 memcpy(s
->pwprompt
, prompt
, prlen
);
7070 strcpy(s
->pwprompt
+ prlen
, trunc
);
7072 memcpy(s
->pwprompt
, prompt
, prompt_len
);
7073 s
->pwprompt
[prompt_len
] = '\0';
7077 "<server failed to send prompt>: ");
7079 s
->echo
= ssh2_pkt_getbool(pktin
);
7085 if (!s
->method
&& s
->can_passwd
) {
7086 s
->method
= AUTH_PASSWORD
;
7087 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
7088 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
7089 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
7096 if (!ssh_get_line(s
->pwprompt
, s
->password
,
7097 sizeof(s
->password
), TRUE
)) {
7099 * get_line failed to get a password (for
7100 * example because one was supplied on the
7101 * command line which has already failed to
7104 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
7105 ssh2_pkt_adduint32(s
->pktout
,SSH2_DISCONNECT_BY_APPLICATION
);
7106 ssh2_pkt_addstring(s
->pktout
, "No more passwords available"
7108 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
7109 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
7110 logevent("Unable to authenticate");
7111 connection_fatal(ssh
->frontend
,
7112 "Unable to authenticate");
7113 ssh
->close_expected
= TRUE
;
7114 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
7118 int ret
; /* need not be saved across crReturn */
7119 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
7122 setup_userpass_input(ssh
, s
->password
,
7123 sizeof(s
->password
), s
->echo
);
7125 crWaitUntilV(!pktin
);
7126 ret
= process_userpass_input(ssh
, in
, inlen
);
7130 c_write_str(ssh
, "\r\n");
7134 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
7136 * We have our passphrase. Now try the actual authentication.
7138 struct ssh2_userkey
*key
;
7139 const char *error
= NULL
;
7141 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
,
7143 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
7144 if (key
== SSH2_WRONG_PASSPHRASE
) {
7145 c_write_str(ssh
, "Wrong passphrase\r\n");
7146 s
->tried_pubkey_config
= FALSE
;
7148 c_write_str(ssh
, "Unable to load private key (");
7149 c_write_str(ssh
, error
);
7150 c_write_str(ssh
, ")\r\n");
7151 s
->tried_pubkey_config
= TRUE
;
7153 /* Send a spurious AUTH_NONE to return to the top. */
7154 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
7155 ssh2_pkt_addstring(s
->pktout
, s
->username
);
7156 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
7157 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
7158 ssh2_pkt_send(ssh
, s
->pktout
);
7159 s
->type
= AUTH_TYPE_NONE
;
7161 unsigned char *pkblob
, *sigblob
, *sigdata
;
7162 int pkblob_len
, sigblob_len
, sigdata_len
;
7166 * We have loaded the private key and the server
7167 * has announced that it's willing to accept it.
7168 * Hallelujah. Generate a signature and send it.
7170 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
7171 ssh2_pkt_addstring(s
->pktout
, s
->username
);
7172 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
7173 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
7174 ssh2_pkt_addbool(s
->pktout
, TRUE
);
7175 ssh2_pkt_addstring(s
->pktout
, key
->alg
->name
);
7176 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
7177 ssh2_pkt_addstring_start(s
->pktout
);
7178 ssh2_pkt_addstring_data(s
->pktout
, (char *)pkblob
, pkblob_len
);
7181 * The data to be signed is:
7185 * followed by everything so far placed in the
7188 sigdata_len
= s
->pktout
->length
- 5 + 4 + 20;
7189 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
7191 sigdata
= snewn(sigdata_len
, unsigned char);
7193 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
7194 PUT_32BIT(sigdata
+p
, 20);
7197 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
7198 memcpy(sigdata
+p
, s
->pktout
->data
+ 5,
7199 s
->pktout
->length
- 5);
7200 p
+= s
->pktout
->length
- 5;
7201 assert(p
== sigdata_len
);
7202 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
7203 sigdata_len
, &sigblob_len
);
7204 ssh2_add_sigblob(ssh
, s
->pktout
, pkblob
, pkblob_len
,
7205 sigblob
, sigblob_len
);
7210 ssh2_pkt_send(ssh
, s
->pktout
);
7211 s
->type
= AUTH_TYPE_PUBLICKEY
;
7212 key
->alg
->freekey(key
->data
);
7214 } else if (s
->method
== AUTH_PASSWORD
) {
7216 * We pad out the password packet to 256 bytes to make
7217 * it harder for an attacker to find the length of the
7220 * Anyone using a password longer than 256 bytes
7221 * probably doesn't have much to worry about from
7222 * people who find out how long their password is!
7224 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
7225 s
->pktout
->forcepad
= 256;
7226 ssh2_pkt_addstring(s
->pktout
, s
->username
);
7227 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
7228 ssh2_pkt_addstring(s
->pktout
, "password");
7229 ssh2_pkt_addbool(s
->pktout
, FALSE
);
7230 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
7231 ssh2_pkt_addstring(s
->pktout
, s
->password
);
7232 memset(s
->password
, 0, sizeof(s
->password
));
7233 end_log_omission(ssh
, s
->pktout
);
7234 ssh2_pkt_send(ssh
, s
->pktout
);
7235 logevent("Sent password");
7236 s
->type
= AUTH_TYPE_PASSWORD
;
7237 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
7238 if (s
->curr_prompt
== 0) {
7239 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
7240 s
->pktout
->forcepad
= 256;
7241 ssh2_pkt_adduint32(s
->pktout
, s
->num_prompts
);
7243 if (s
->need_pw
) { /* only add pw if we just got one! */
7244 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
7245 ssh2_pkt_addstring(s
->pktout
, s
->password
);
7246 memset(s
->password
, 0, sizeof(s
->password
));
7247 end_log_omission(ssh
, s
->pktout
);
7250 if (s
->curr_prompt
>= s
->num_prompts
) {
7251 ssh2_pkt_send(ssh
, s
->pktout
);
7254 * If there are prompts remaining, we set
7255 * `gotit' so that we won't attempt to get
7256 * another packet. Then we go back round the
7257 * loop and will end up retrieving another
7258 * prompt out of the existing packet. Funky or
7263 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
7265 c_write_str(ssh
, "No supported authentication methods"
7266 " left to try!\r\n");
7267 logevent("No supported authentications offered."
7269 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
7270 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
7271 ssh2_pkt_addstring(s
->pktout
, "No supported authentication"
7272 " methods available");
7273 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
7274 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
7275 ssh
->close_expected
= TRUE
;
7276 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
7281 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
7284 * Now the connection protocol has started, one way or another.
7287 ssh
->channels
= newtree234(ssh_channelcmp
);
7290 * Set up handlers for some connection protocol messages, so we
7291 * don't have to handle them repeatedly in this coroutine.
7293 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] =
7294 ssh2_msg_channel_window_adjust
;
7295 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] =
7296 ssh2_msg_global_request
;
7299 * Create the main session channel.
7301 if (!ssh
->cfg
.ssh_no_shell
) {
7302 ssh
->mainchan
= snew(struct ssh_channel
);
7303 ssh
->mainchan
->ssh
= ssh
;
7304 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
7305 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
7306 ssh2_pkt_addstring(s
->pktout
, "session");
7307 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->localid
);
7308 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7309 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
7310 ssh2_pkt_adduint32(s
->pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
7311 ssh2_pkt_send(ssh
, s
->pktout
);
7312 crWaitUntilV(pktin
);
7313 if (pktin
->type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
7314 bombout(("Server refused to open a session"));
7316 /* FIXME: error data comes back in FAILURE packet */
7318 if (ssh_pkt_getuint32(pktin
) != ssh
->mainchan
->localid
) {
7319 bombout(("Server's channel confirmation cited wrong channel"));
7322 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(pktin
);
7323 ssh
->mainchan
->halfopen
= FALSE
;
7324 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
7325 ssh
->mainchan
->closes
= 0;
7326 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
7327 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
7328 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
7329 add234(ssh
->channels
, ssh
->mainchan
);
7330 update_specials_menu(ssh
->frontend
);
7331 logevent("Opened channel for session");
7333 ssh
->mainchan
= NULL
;
7336 * Now we have a channel, make dispatch table entries for
7337 * general channel-based messages.
7339 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] =
7340 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] =
7341 ssh2_msg_channel_data
;
7342 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = ssh2_msg_channel_eof
;
7343 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = ssh2_msg_channel_close
;
7344 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] =
7345 ssh2_msg_channel_open_confirmation
;
7346 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] =
7347 ssh2_msg_channel_open_failure
;
7348 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] =
7349 ssh2_msg_channel_request
;
7350 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] =
7351 ssh2_msg_channel_open
;
7354 * Potentially enable X11 forwarding.
7356 if (ssh
->mainchan
&& ssh
->cfg
.x11_forward
) {
7357 char proto
[20], data
[64];
7358 logevent("Requesting X11 forwarding");
7359 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
7360 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
7361 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
7362 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7363 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7364 ssh2_pkt_addstring(s
->pktout
, "x11-req");
7365 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7366 ssh2_pkt_addbool(s
->pktout
, 0); /* many connections */
7367 ssh2_pkt_addstring(s
->pktout
, proto
);
7369 * Note that while we blank the X authentication data here, we don't
7370 * take any special action to blank the start of an X11 channel,
7371 * so using MIT-MAGIC-COOKIE-1 and actually opening an X connection
7372 * without having session blanking enabled is likely to leak your
7373 * cookie into the log.
7375 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
7376 ssh2_pkt_addstring(s
->pktout
, data
);
7377 end_log_omission(ssh
, s
->pktout
);
7378 ssh2_pkt_adduint32(s
->pktout
, x11_get_screen_number(ssh
->cfg
.x11_display
));
7379 ssh2_pkt_send(ssh
, s
->pktout
);
7381 crWaitUntilV(pktin
);
7383 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7384 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7385 bombout(("Unexpected response to X11 forwarding request:"
7386 " packet type %d", pktin
->type
));
7389 logevent("X11 forwarding refused");
7391 logevent("X11 forwarding enabled");
7392 ssh
->X11_fwd_enabled
= TRUE
;
7397 * Enable port forwardings.
7399 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
7402 * Potentially enable agent forwarding.
7404 if (ssh
->mainchan
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
7405 logevent("Requesting OpenSSH-style agent forwarding");
7406 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7407 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7408 ssh2_pkt_addstring(s
->pktout
, "auth-agent-req@openssh.com");
7409 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7410 ssh2_pkt_send(ssh
, s
->pktout
);
7412 crWaitUntilV(pktin
);
7414 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7415 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7416 bombout(("Unexpected response to agent forwarding request:"
7417 " packet type %d", pktin
->type
));
7420 logevent("Agent forwarding refused");
7422 logevent("Agent forwarding enabled");
7423 ssh
->agentfwd_enabled
= TRUE
;
7428 * Now allocate a pty for the session.
7430 if (ssh
->mainchan
&& !ssh
->cfg
.nopty
) {
7431 /* Unpick the terminal-speed string. */
7432 /* XXX perhaps we should allow no speeds to be sent. */
7433 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
7434 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
7435 /* Build the pty request. */
7436 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7437 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7438 ssh2_pkt_addstring(s
->pktout
, "pty-req");
7439 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7440 ssh2_pkt_addstring(s
->pktout
, ssh
->cfg
.termtype
);
7441 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_width
);
7442 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_height
);
7443 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel width */
7444 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel height */
7445 ssh2_pkt_addstring_start(s
->pktout
);
7446 parse_ttymodes(ssh
, ssh
->cfg
.ttymodes
,
7447 ssh2_send_ttymode
, (void *)s
->pktout
);
7448 ssh2_pkt_addbyte(s
->pktout
, SSH2_TTY_OP_ISPEED
);
7449 ssh2_pkt_adduint32(s
->pktout
, ssh
->ispeed
);
7450 ssh2_pkt_addbyte(s
->pktout
, SSH2_TTY_OP_OSPEED
);
7451 ssh2_pkt_adduint32(s
->pktout
, ssh
->ospeed
);
7452 ssh2_pkt_addstring_data(s
->pktout
, "\0", 1); /* TTY_OP_END */
7453 ssh2_pkt_send(ssh
, s
->pktout
);
7454 ssh
->state
= SSH_STATE_INTERMED
;
7456 crWaitUntilV(pktin
);
7458 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7459 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7460 bombout(("Unexpected response to pty request:"
7461 " packet type %d", pktin
->type
));
7464 c_write_str(ssh
, "Server refused to allocate pty\r\n");
7465 ssh
->editing
= ssh
->echoing
= 1;
7467 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
7468 ssh
->ospeed
, ssh
->ispeed
);
7471 ssh
->editing
= ssh
->echoing
= 1;
7475 * Send environment variables.
7477 * Simplest thing here is to send all the requests at once, and
7478 * then wait for a whole bunch of successes or failures.
7480 if (ssh
->mainchan
&& *ssh
->cfg
.environmt
) {
7481 char *e
= ssh
->cfg
.environmt
;
7482 char *var
, *varend
, *val
;
7488 while (*e
&& *e
!= '\t') e
++;
7490 if (*e
== '\t') e
++;
7495 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7496 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7497 ssh2_pkt_addstring(s
->pktout
, "env");
7498 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7499 ssh2_pkt_addstring_start(s
->pktout
);
7500 ssh2_pkt_addstring_data(s
->pktout
, var
, varend
-var
);
7501 ssh2_pkt_addstring(s
->pktout
, val
);
7502 ssh2_pkt_send(ssh
, s
->pktout
);
7507 logeventf(ssh
, "Sent %d environment variables", s
->num_env
);
7510 s
->env_left
= s
->num_env
;
7512 while (s
->env_left
> 0) {
7513 crWaitUntilV(pktin
);
7515 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7516 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7517 bombout(("Unexpected response to environment request:"
7518 " packet type %d", pktin
->type
));
7528 if (s
->env_ok
== s
->num_env
) {
7529 logevent("All environment variables successfully set");
7530 } else if (s
->env_ok
== 0) {
7531 logevent("All environment variables refused");
7532 c_write_str(ssh
, "Server refused to set environment variables\r\n");
7534 logeventf(ssh
, "%d environment variables refused",
7535 s
->num_env
- s
->env_ok
);
7536 c_write_str(ssh
, "Server refused to set all environment variables\r\n");
7541 * Start a shell or a remote command. We may have to attempt
7542 * this twice if the config data has provided a second choice
7545 if (ssh
->mainchan
) while (1) {
7549 if (ssh
->fallback_cmd
) {
7550 subsys
= ssh
->cfg
.ssh_subsys2
;
7551 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
7553 subsys
= ssh
->cfg
.ssh_subsys
;
7554 cmd
= ssh
->cfg
.remote_cmd_ptr
;
7555 if (!cmd
) cmd
= ssh
->cfg
.remote_cmd
;
7558 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7559 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7561 ssh2_pkt_addstring(s
->pktout
, "subsystem");
7562 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7563 ssh2_pkt_addstring(s
->pktout
, cmd
);
7565 ssh2_pkt_addstring(s
->pktout
, "exec");
7566 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7567 ssh2_pkt_addstring(s
->pktout
, cmd
);
7569 ssh2_pkt_addstring(s
->pktout
, "shell");
7570 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7572 ssh2_pkt_send(ssh
, s
->pktout
);
7574 crWaitUntilV(pktin
);
7576 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7577 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7578 bombout(("Unexpected response to shell/command request:"
7579 " packet type %d", pktin
->type
));
7583 * We failed to start the command. If this is the
7584 * fallback command, we really are finished; if it's
7585 * not, and if the fallback command exists, try falling
7586 * back to it before complaining.
7588 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
7589 logevent("Primary command failed; attempting fallback");
7590 ssh
->fallback_cmd
= TRUE
;
7593 bombout(("Server refused to start a shell/command"));
7596 logevent("Started a shell/command");
7601 ssh
->state
= SSH_STATE_SESSION
;
7602 if (ssh
->size_needed
)
7603 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
7604 if (ssh
->eof_needed
)
7605 ssh_special(ssh
, TS_EOF
);
7611 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
7616 s
->try_send
= FALSE
;
7620 * _All_ the connection-layer packets we expect to
7621 * receive are now handled by the dispatch table.
7622 * Anything that reaches here must be bogus.
7625 bombout(("Strange packet received: type %d", pktin
->type
));
7627 } else if (ssh
->mainchan
) {
7629 * We have spare data. Add it to the channel buffer.
7631 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
7636 struct ssh_channel
*c
;
7638 * Try to send data on all channels if we can.
7640 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++)
7641 ssh2_try_send_and_unthrottle(c
);
7649 * Handlers for SSH-2 messages that might arrive at any moment.
7651 static void ssh2_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
7653 /* log reason code in disconnect message */
7655 int nowlen
, reason
, msglen
;
7657 reason
= ssh_pkt_getuint32(pktin
);
7658 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7660 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
7661 buf
= dupprintf("Received disconnect message (%s)",
7662 ssh2_disconnect_reasons
[reason
]);
7664 buf
= dupprintf("Received disconnect message (unknown"
7665 " type %d)", reason
);
7669 buf
= dupprintf("Disconnection message text: %n%.*s",
7670 &nowlen
, msglen
, msg
);
7672 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7674 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
7675 ssh2_disconnect_reasons
[reason
] : "unknown",
7680 static void ssh2_msg_debug(Ssh ssh
, struct Packet
*pktin
)
7682 /* log the debug message */
7687 /* XXX maybe we should actually take notice of this */
7688 always_display
= ssh2_pkt_getbool(pktin
);
7689 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7691 logeventf(ssh
, "Remote debug message: %.*s", msglen
, msg
);
7694 static void ssh2_msg_something_unimplemented(Ssh ssh
, struct Packet
*pktin
)
7696 struct Packet
*pktout
;
7697 pktout
= ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
7698 ssh2_pkt_adduint32(pktout
, pktin
->sequence
);
7700 * UNIMPLEMENTED messages MUST appear in the same order as the
7701 * messages they respond to. Hence, never queue them.
7703 ssh2_pkt_send_noqueue(ssh
, pktout
);
7707 * Handle the top-level SSH-2 protocol.
7709 static void ssh2_protocol_setup(Ssh ssh
)
7714 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7716 for (i
= 0; i
< 256; i
++)
7717 ssh
->packet_dispatch
[i
] = ssh2_msg_something_unimplemented
;
7720 * Any message we actually understand, we set to NULL so that
7721 * the coroutines will get it.
7723 ssh
->packet_dispatch
[SSH2_MSG_UNIMPLEMENTED
] = NULL
;
7724 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_REQUEST
] = NULL
;
7725 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_ACCEPT
] = NULL
;
7726 ssh
->packet_dispatch
[SSH2_MSG_KEXINIT
] = NULL
;
7727 ssh
->packet_dispatch
[SSH2_MSG_NEWKEYS
] = NULL
;
7728 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_INIT
] = NULL
;
7729 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_REPLY
] = NULL
;
7730 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7731 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7732 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_INIT
] = NULL
;
7733 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_REPLY
] = NULL
;
7734 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_REQUEST
] = NULL
;
7735 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_FAILURE
] = NULL
;
7736 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_SUCCESS
] = NULL
;
7737 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
7738 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_PK_OK
] = NULL
;
7739 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7740 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7741 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_INFO_RESPONSE
] = NULL
;
7742 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] = NULL
;
7743 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_SUCCESS
] = NULL
;
7744 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_FAILURE
] = NULL
;
7745 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] = NULL
;
7746 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] = NULL
;
7747 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] = NULL
;
7748 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] = NULL
;
7749 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] = NULL
;
7750 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] = NULL
;
7751 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = NULL
;
7752 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = NULL
;
7753 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] = NULL
;
7754 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_SUCCESS
] = NULL
;
7755 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_FAILURE
] = NULL
;
7758 * These special message types we install handlers for.
7760 ssh
->packet_dispatch
[SSH2_MSG_DISCONNECT
] = ssh2_msg_disconnect
;
7761 ssh
->packet_dispatch
[SSH2_MSG_IGNORE
] = ssh_msg_ignore
; /* shared with SSH-1 */
7762 ssh
->packet_dispatch
[SSH2_MSG_DEBUG
] = ssh2_msg_debug
;
7765 static void ssh2_timer(void *ctx
, long now
)
7769 if (ssh
->state
== SSH_STATE_CLOSED
)
7772 if (!ssh
->kex_in_progress
&& ssh
->cfg
.ssh_rekey_time
!= 0 &&
7773 now
- ssh
->next_rekey
>= 0) {
7774 do_ssh2_transport(ssh
, "timeout", -1, NULL
);
7778 static void ssh2_protocol(Ssh ssh
, void *vin
, int inlen
,
7779 struct Packet
*pktin
)
7781 unsigned char *in
= (unsigned char *)vin
;
7782 if (ssh
->state
== SSH_STATE_CLOSED
)
7786 ssh
->incoming_data_size
+= pktin
->encrypted_len
;
7787 if (!ssh
->kex_in_progress
&&
7788 ssh
->max_data_size
!= 0 &&
7789 ssh
->incoming_data_size
> ssh
->max_data_size
)
7790 do_ssh2_transport(ssh
, "too much data received", -1, NULL
);
7793 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
7794 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
7798 if (!ssh
->protocol_initial_phase_done
||
7799 (pktin
&& pktin
->type
>= 20 && pktin
->type
< 50)) {
7800 if (do_ssh2_transport(ssh
, in
, inlen
, pktin
) &&
7801 !ssh
->protocol_initial_phase_done
) {
7802 ssh
->protocol_initial_phase_done
= TRUE
;
7804 * Allow authconn to initialise itself.
7806 do_ssh2_authconn(ssh
, NULL
, 0, NULL
);
7809 do_ssh2_authconn(ssh
, in
, inlen
, pktin
);
7814 * Called to set up the connection.
7816 * Returns an error message, or NULL on success.
7818 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
7820 char *host
, int port
, char **realhost
, int nodelay
,
7826 ssh
= snew(struct ssh_tag
);
7827 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7828 ssh
->version
= 0; /* when not ready yet */
7831 ssh
->v1_cipher_ctx
= NULL
;
7832 ssh
->crcda_ctx
= NULL
;
7833 ssh
->cscipher
= NULL
;
7834 ssh
->cs_cipher_ctx
= NULL
;
7835 ssh
->sccipher
= NULL
;
7836 ssh
->sc_cipher_ctx
= NULL
;
7838 ssh
->cs_mac_ctx
= NULL
;
7840 ssh
->sc_mac_ctx
= NULL
;
7842 ssh
->cs_comp_ctx
= NULL
;
7844 ssh
->sc_comp_ctx
= NULL
;
7846 ssh
->kex_ctx
= NULL
;
7847 ssh
->hostkey
= NULL
;
7849 ssh
->close_expected
= FALSE
;
7850 ssh
->state
= SSH_STATE_PREPACKET
;
7851 ssh
->size_needed
= FALSE
;
7852 ssh
->eof_needed
= FALSE
;
7855 ssh
->deferred_send_data
= NULL
;
7856 ssh
->deferred_len
= 0;
7857 ssh
->deferred_size
= 0;
7858 ssh
->fallback_cmd
= 0;
7860 ssh
->x11auth
= NULL
;
7861 ssh
->v1_compressing
= FALSE
;
7862 ssh
->v2_outgoing_sequence
= 0;
7863 ssh
->ssh1_rdpkt_crstate
= 0;
7864 ssh
->ssh2_rdpkt_crstate
= 0;
7865 ssh
->do_ssh_init_crstate
= 0;
7866 ssh
->ssh_gotdata_crstate
= 0;
7867 ssh
->do_ssh1_connection_crstate
= 0;
7868 ssh
->do_ssh1_login_crstate
= 0;
7869 ssh
->do_ssh2_transport_crstate
= 0;
7870 ssh
->do_ssh2_authconn_crstate
= 0;
7871 ssh
->do_ssh_init_state
= NULL
;
7872 ssh
->do_ssh1_login_state
= NULL
;
7873 ssh
->do_ssh2_transport_state
= NULL
;
7874 ssh
->do_ssh2_authconn_state
= NULL
;
7875 ssh
->mainchan
= NULL
;
7876 ssh
->throttled_all
= 0;
7877 ssh
->v1_stdout_throttling
= 0;
7879 ssh
->queuelen
= ssh
->queuesize
= 0;
7880 ssh
->queueing
= FALSE
;
7881 ssh
->qhead
= ssh
->qtail
= NULL
;
7882 ssh
->deferred_rekey_reason
= NULL
;
7883 bufchain_init(&ssh
->queued_incoming_data
);
7884 ssh
->frozen
= FALSE
;
7886 *backend_handle
= ssh
;
7889 if (crypto_startup() == 0)
7890 return "Microsoft high encryption pack not installed!";
7893 ssh
->frontend
= frontend_handle
;
7894 ssh
->term_width
= ssh
->cfg
.width
;
7895 ssh
->term_height
= ssh
->cfg
.height
;
7897 ssh
->channels
= NULL
;
7898 ssh
->rportfwds
= NULL
;
7899 ssh
->portfwds
= NULL
;
7904 ssh
->v1_throttle_count
= 0;
7905 ssh
->overall_bufsize
= 0;
7906 ssh
->fallback_cmd
= 0;
7908 ssh
->protocol
= NULL
;
7910 ssh
->protocol_initial_phase_done
= FALSE
;
7914 ssh
->incoming_data_size
= ssh
->outgoing_data_size
=
7915 ssh
->deferred_data_size
= 0L;
7916 ssh
->max_data_size
= parse_blocksize(ssh
->cfg
.ssh_rekey_data
);
7917 ssh
->kex_in_progress
= FALSE
;
7919 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
7928 static void ssh_free(void *handle
)
7930 Ssh ssh
= (Ssh
) handle
;
7931 struct ssh_channel
*c
;
7932 struct ssh_rportfwd
*pf
;
7934 if (ssh
->v1_cipher_ctx
)
7935 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
7936 if (ssh
->cs_cipher_ctx
)
7937 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
7938 if (ssh
->sc_cipher_ctx
)
7939 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
7940 if (ssh
->cs_mac_ctx
)
7941 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
7942 if (ssh
->sc_mac_ctx
)
7943 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
7944 if (ssh
->cs_comp_ctx
) {
7946 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
7948 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
7950 if (ssh
->sc_comp_ctx
) {
7952 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
7954 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
7957 dh_cleanup(ssh
->kex_ctx
);
7958 sfree(ssh
->savedhost
);
7960 while (ssh
->queuelen
-- > 0)
7961 ssh_free_packet(ssh
->queue
[ssh
->queuelen
]);
7964 while (ssh
->qhead
) {
7965 struct queued_handler
*qh
= ssh
->qhead
;
7966 ssh
->qhead
= qh
->next
;
7969 ssh
->qhead
= ssh
->qtail
= NULL
;
7971 if (ssh
->channels
) {
7972 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
7975 if (c
->u
.x11
.s
!= NULL
)
7976 x11_close(c
->u
.x11
.s
);
7979 if (c
->u
.pfd
.s
!= NULL
)
7980 pfd_close(c
->u
.pfd
.s
);
7985 freetree234(ssh
->channels
);
7986 ssh
->channels
= NULL
;
7989 if (ssh
->rportfwds
) {
7990 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
7992 freetree234(ssh
->rportfwds
);
7993 ssh
->rportfwds
= NULL
;
7995 sfree(ssh
->deferred_send_data
);
7997 x11_free_auth(ssh
->x11auth
);
7998 sfree(ssh
->do_ssh_init_state
);
7999 sfree(ssh
->do_ssh1_login_state
);
8000 sfree(ssh
->do_ssh2_transport_state
);
8001 sfree(ssh
->do_ssh2_authconn_state
);
8002 if (ssh
->crcda_ctx
) {
8003 crcda_free_context(ssh
->crcda_ctx
);
8004 ssh
->crcda_ctx
= NULL
;
8007 ssh_do_close(ssh
, TRUE
);
8008 expire_timer_context(ssh
);
8010 pinger_free(ssh
->pinger
);
8011 bufchain_clear(&ssh
->queued_incoming_data
);
8018 * Reconfigure the SSH backend.
8020 static void ssh_reconfig(void *handle
, Config
*cfg
)
8022 Ssh ssh
= (Ssh
) handle
;
8023 char *rekeying
= NULL
, rekey_mandatory
= FALSE
;
8024 unsigned long old_max_data_size
;
8026 pinger_reconfig(ssh
->pinger
, &ssh
->cfg
, cfg
);
8027 ssh_setup_portfwd(ssh
, cfg
);
8029 if (ssh
->cfg
.ssh_rekey_time
!= cfg
->ssh_rekey_time
&&
8030 cfg
->ssh_rekey_time
!= 0) {
8031 long new_next
= ssh
->last_rekey
+ cfg
->ssh_rekey_time
*60*TICKSPERSEC
;
8032 long now
= GETTICKCOUNT();
8034 if (new_next
- now
< 0) {
8035 rekeying
= "timeout shortened";
8037 ssh
->next_rekey
= schedule_timer(new_next
- now
, ssh2_timer
, ssh
);
8041 old_max_data_size
= ssh
->max_data_size
;
8042 ssh
->max_data_size
= parse_blocksize(cfg
->ssh_rekey_data
);
8043 if (old_max_data_size
!= ssh
->max_data_size
&&
8044 ssh
->max_data_size
!= 0) {
8045 if (ssh
->outgoing_data_size
> ssh
->max_data_size
||
8046 ssh
->incoming_data_size
> ssh
->max_data_size
)
8047 rekeying
= "data limit lowered";
8050 if (ssh
->cfg
.compression
!= cfg
->compression
) {
8051 rekeying
= "compression setting changed";
8052 rekey_mandatory
= TRUE
;
8055 if (ssh
->cfg
.ssh2_des_cbc
!= cfg
->ssh2_des_cbc
||
8056 memcmp(ssh
->cfg
.ssh_cipherlist
, cfg
->ssh_cipherlist
,
8057 sizeof(ssh
->cfg
.ssh_cipherlist
))) {
8058 rekeying
= "cipher settings changed";
8059 rekey_mandatory
= TRUE
;
8062 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
8065 if (!ssh
->kex_in_progress
) {
8066 do_ssh2_transport(ssh
, rekeying
, -1, NULL
);
8067 } else if (rekey_mandatory
) {
8068 ssh
->deferred_rekey_reason
= rekeying
;
8074 * Called to send data down the Telnet connection.
8076 static int ssh_send(void *handle
, char *buf
, int len
)
8078 Ssh ssh
= (Ssh
) handle
;
8080 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
8083 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
8085 return ssh_sendbuffer(ssh
);
8089 * Called to query the current amount of buffered stdin data.
8091 static int ssh_sendbuffer(void *handle
)
8093 Ssh ssh
= (Ssh
) handle
;
8096 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
8100 * If the SSH socket itself has backed up, add the total backup
8101 * size on that to any individual buffer on the stdin channel.
8104 if (ssh
->throttled_all
)
8105 override_value
= ssh
->overall_bufsize
;
8107 if (ssh
->version
== 1) {
8108 return override_value
;
8109 } else if (ssh
->version
== 2) {
8110 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
8111 return override_value
;
8113 return (override_value
+
8114 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
8121 * Called to set the size of the window from SSH's POV.
8123 static void ssh_size(void *handle
, int width
, int height
)
8125 Ssh ssh
= (Ssh
) handle
;
8126 struct Packet
*pktout
;
8128 ssh
->term_width
= width
;
8129 ssh
->term_height
= height
;
8131 switch (ssh
->state
) {
8132 case SSH_STATE_BEFORE_SIZE
:
8133 case SSH_STATE_PREPACKET
:
8134 case SSH_STATE_CLOSED
:
8135 break; /* do nothing */
8136 case SSH_STATE_INTERMED
:
8137 ssh
->size_needed
= TRUE
; /* buffer for later */
8139 case SSH_STATE_SESSION
:
8140 if (!ssh
->cfg
.nopty
) {
8141 if (ssh
->version
== 1) {
8142 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
8143 PKT_INT
, ssh
->term_height
,
8144 PKT_INT
, ssh
->term_width
,
8145 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
8146 } else if (ssh
->mainchan
) {
8147 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
8148 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8149 ssh2_pkt_addstring(pktout
, "window-change");
8150 ssh2_pkt_addbool(pktout
, 0);
8151 ssh2_pkt_adduint32(pktout
, ssh
->term_width
);
8152 ssh2_pkt_adduint32(pktout
, ssh
->term_height
);
8153 ssh2_pkt_adduint32(pktout
, 0);
8154 ssh2_pkt_adduint32(pktout
, 0);
8155 ssh2_pkt_send(ssh
, pktout
);
8163 * Return a list of the special codes that make sense in this
8166 static const struct telnet_special
*ssh_get_specials(void *handle
)
8168 static const struct telnet_special ssh1_ignore_special
[] = {
8169 {"IGNORE message", TS_NOP
}
8171 static const struct telnet_special ssh2_transport_specials
[] = {
8172 {"IGNORE message", TS_NOP
},
8173 {"Repeat key exchange", TS_REKEY
},
8175 static const struct telnet_special ssh2_session_specials
[] = {
8178 /* These are the signal names defined by draft-ietf-secsh-connect-23.
8179 * They include all the ISO C signals, but are a subset of the POSIX
8180 * required signals. */
8181 {"SIGINT (Interrupt)", TS_SIGINT
},
8182 {"SIGTERM (Terminate)", TS_SIGTERM
},
8183 {"SIGKILL (Kill)", TS_SIGKILL
},
8184 {"SIGQUIT (Quit)", TS_SIGQUIT
},
8185 {"SIGHUP (Hangup)", TS_SIGHUP
},
8186 {"More signals", TS_SUBMENU
},
8187 {"SIGABRT", TS_SIGABRT
}, {"SIGALRM", TS_SIGALRM
},
8188 {"SIGFPE", TS_SIGFPE
}, {"SIGILL", TS_SIGILL
},
8189 {"SIGPIPE", TS_SIGPIPE
}, {"SIGSEGV", TS_SIGSEGV
},
8190 {"SIGUSR1", TS_SIGUSR1
}, {"SIGUSR2", TS_SIGUSR2
},
8193 static const struct telnet_special specials_end
[] = {
8196 /* XXX review this length for any changes: */
8197 static struct telnet_special ssh_specials
[lenof(ssh2_transport_specials
) +
8198 lenof(ssh2_session_specials
) +
8199 lenof(specials_end
)];
8200 Ssh ssh
= (Ssh
) handle
;
8202 #define ADD_SPECIALS(name) \
8204 assert((i + lenof(name)) <= lenof(ssh_specials)); \
8205 memcpy(&ssh_specials[i], name, sizeof name); \
8209 if (ssh
->version
== 1) {
8210 /* Don't bother offering IGNORE if we've decided the remote
8211 * won't cope with it, since we wouldn't bother sending it if
8213 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
8214 ADD_SPECIALS(ssh1_ignore_special
);
8215 } else if (ssh
->version
== 2) {
8216 ADD_SPECIALS(ssh2_transport_specials
);
8218 ADD_SPECIALS(ssh2_session_specials
);
8219 } /* else we're not ready yet */
8222 ADD_SPECIALS(specials_end
);
8223 return ssh_specials
;
8231 * Send Telnet special codes. TS_EOF is useful for `plink', so you
8232 * can send an EOF and collect resulting output (e.g. `plink
8235 static void ssh_special(void *handle
, Telnet_Special code
)
8237 Ssh ssh
= (Ssh
) handle
;
8238 struct Packet
*pktout
;
8240 if (code
== TS_EOF
) {
8241 if (ssh
->state
!= SSH_STATE_SESSION
) {
8243 * Buffer the EOF in case we are pre-SESSION, so we can
8244 * send it as soon as we reach SESSION.
8247 ssh
->eof_needed
= TRUE
;
8250 if (ssh
->version
== 1) {
8251 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
8252 } else if (ssh
->mainchan
) {
8253 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
8254 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8255 ssh2_pkt_send(ssh
, pktout
);
8256 ssh
->send_ok
= 0; /* now stop trying to read from stdin */
8258 logevent("Sent EOF message");
8259 } else if (code
== TS_PING
|| code
== TS_NOP
) {
8260 if (ssh
->state
== SSH_STATE_CLOSED
8261 || ssh
->state
== SSH_STATE_PREPACKET
) return;
8262 if (ssh
->version
== 1) {
8263 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
8264 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
8266 pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
8267 ssh2_pkt_addstring_start(pktout
);
8268 ssh2_pkt_send_noqueue(ssh
, pktout
);
8270 } else if (code
== TS_REKEY
) {
8271 if (!ssh
->kex_in_progress
&& ssh
->version
== 2) {
8272 do_ssh2_transport(ssh
, "at user request", -1, NULL
);
8274 } else if (code
== TS_BRK
) {
8275 if (ssh
->state
== SSH_STATE_CLOSED
8276 || ssh
->state
== SSH_STATE_PREPACKET
) return;
8277 if (ssh
->version
== 1) {
8278 logevent("Unable to send BREAK signal in SSH-1");
8279 } else if (ssh
->mainchan
) {
8280 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
8281 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8282 ssh2_pkt_addstring(pktout
, "break");
8283 ssh2_pkt_addbool(pktout
, 0);
8284 ssh2_pkt_adduint32(pktout
, 0); /* default break length */
8285 ssh2_pkt_send(ssh
, pktout
);
8288 /* Is is a POSIX signal? */
8289 char *signame
= NULL
;
8290 if (code
== TS_SIGABRT
) signame
= "ABRT";
8291 if (code
== TS_SIGALRM
) signame
= "ALRM";
8292 if (code
== TS_SIGFPE
) signame
= "FPE";
8293 if (code
== TS_SIGHUP
) signame
= "HUP";
8294 if (code
== TS_SIGILL
) signame
= "ILL";
8295 if (code
== TS_SIGINT
) signame
= "INT";
8296 if (code
== TS_SIGKILL
) signame
= "KILL";
8297 if (code
== TS_SIGPIPE
) signame
= "PIPE";
8298 if (code
== TS_SIGQUIT
) signame
= "QUIT";
8299 if (code
== TS_SIGSEGV
) signame
= "SEGV";
8300 if (code
== TS_SIGTERM
) signame
= "TERM";
8301 if (code
== TS_SIGUSR1
) signame
= "USR1";
8302 if (code
== TS_SIGUSR2
) signame
= "USR2";
8303 /* The SSH-2 protocol does in principle support arbitrary named
8304 * signals, including signame@domain, but we don't support those. */
8306 /* It's a signal. */
8307 if (ssh
->version
== 2 && ssh
->mainchan
) {
8308 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
8309 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8310 ssh2_pkt_addstring(pktout
, "signal");
8311 ssh2_pkt_addbool(pktout
, 0);
8312 ssh2_pkt_addstring(pktout
, signame
);
8313 ssh2_pkt_send(ssh
, pktout
);
8314 logeventf(ssh
, "Sent signal SIG%s", signame
);
8317 /* Never heard of it. Do nothing */
8322 void *new_sock_channel(void *handle
, Socket s
)
8324 Ssh ssh
= (Ssh
) handle
;
8325 struct ssh_channel
*c
;
8326 c
= snew(struct ssh_channel
);
8331 c
->localid
= alloc_channel_id(ssh
);
8333 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
8335 bufchain_init(&c
->v
.v2
.outbuffer
);
8336 add234(ssh
->channels
, c
);
8342 * This is called when stdout/stderr (the entity to which
8343 * from_backend sends data) manages to clear some backlog.
8345 static void ssh_unthrottle(void *handle
, int bufsize
)
8347 Ssh ssh
= (Ssh
) handle
;
8348 if (ssh
->version
== 1) {
8349 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
8350 ssh
->v1_stdout_throttling
= 0;
8351 ssh1_throttle(ssh
, -1);
8354 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
8355 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
8359 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
8361 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
8363 struct Packet
*pktout
;
8365 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
8367 if (ssh
->version
== 1) {
8368 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
8369 PKT_INT
, c
->localid
,
8372 /* PKT_STR, <org:orgport>, */
8375 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
8376 ssh2_pkt_addstring(pktout
, "direct-tcpip");
8377 ssh2_pkt_adduint32(pktout
, c
->localid
);
8378 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
8379 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);/* our window size */
8380 ssh2_pkt_adduint32(pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
8381 ssh2_pkt_addstring(pktout
, hostname
);
8382 ssh2_pkt_adduint32(pktout
, port
);
8384 * We make up values for the originator data; partly it's
8385 * too much hassle to keep track, and partly I'm not
8386 * convinced the server should be told details like that
8387 * about my local network configuration.
8389 ssh2_pkt_addstring(pktout
, "client-side-connection");
8390 ssh2_pkt_adduint32(pktout
, 0);
8391 ssh2_pkt_send(ssh
, pktout
);
8395 static Socket
ssh_socket(void *handle
)
8397 Ssh ssh
= (Ssh
) handle
;
8401 static int ssh_sendok(void *handle
)
8403 Ssh ssh
= (Ssh
) handle
;
8404 return ssh
->send_ok
;
8407 static int ssh_ldisc(void *handle
, int option
)
8409 Ssh ssh
= (Ssh
) handle
;
8410 if (option
== LD_ECHO
)
8411 return ssh
->echoing
;
8412 if (option
== LD_EDIT
)
8413 return ssh
->editing
;
8417 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
8419 Ssh ssh
= (Ssh
) handle
;
8423 static void ssh_provide_logctx(void *handle
, void *logctx
)
8425 Ssh ssh
= (Ssh
) handle
;
8426 ssh
->logctx
= logctx
;
8429 static int ssh_return_exitcode(void *handle
)
8431 Ssh ssh
= (Ssh
) handle
;
8435 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
8439 * cfg_info for SSH is the currently running version of the
8440 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
8442 static int ssh_cfg_info(void *handle
)
8444 Ssh ssh
= (Ssh
) handle
;
8445 return ssh
->version
;
8449 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
8450 * that fails. This variable is the means by which scp.c can reach
8451 * into the SSH code and find out which one it got.
8453 extern int ssh_fallback_cmd(void *handle
)
8455 Ssh ssh
= (Ssh
) handle
;
8456 return ssh
->fallback_cmd
;
8459 Backend ssh_backend
= {
8469 ssh_return_exitcode
,