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_PUBLICKEY 0x0010
110 #define SSH2_PKTCTX_PASSWORD 0x0020
111 #define SSH2_PKTCTX_KBDINTER 0x0040
112 #define SSH2_PKTCTX_AUTH_MASK 0x00F0
114 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
115 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
116 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
117 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
118 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
119 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
120 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
121 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
122 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
123 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
124 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
125 #define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
126 #define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
127 #define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
128 #define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
130 static const char *const ssh2_disconnect_reasons
[] = {
132 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
133 "SSH_DISCONNECT_PROTOCOL_ERROR",
134 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
135 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
136 "SSH_DISCONNECT_MAC_ERROR",
137 "SSH_DISCONNECT_COMPRESSION_ERROR",
138 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
139 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
140 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
141 "SSH_DISCONNECT_CONNECTION_LOST",
142 "SSH_DISCONNECT_BY_APPLICATION",
143 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
144 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
145 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
146 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
149 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
150 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
151 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
152 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
154 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
157 * Various remote-bug flags.
159 #define BUG_CHOKES_ON_SSH1_IGNORE 1
160 #define BUG_SSH2_HMAC 2
161 #define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
162 #define BUG_CHOKES_ON_RSA 8
163 #define BUG_SSH2_RSA_PADDING 16
164 #define BUG_SSH2_DERIVEKEY 32
165 /* 64 was BUG_SSH2_DH_GEX, now spare */
166 #define BUG_SSH2_PK_SESSIONID 128
168 #define translate(x) if (type == x) return #x
169 #define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
170 static char *ssh1_pkt_type(int type
)
172 translate(SSH1_MSG_DISCONNECT
);
173 translate(SSH1_SMSG_PUBLIC_KEY
);
174 translate(SSH1_CMSG_SESSION_KEY
);
175 translate(SSH1_CMSG_USER
);
176 translate(SSH1_CMSG_AUTH_RSA
);
177 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE
);
178 translate(SSH1_CMSG_AUTH_RSA_RESPONSE
);
179 translate(SSH1_CMSG_AUTH_PASSWORD
);
180 translate(SSH1_CMSG_REQUEST_PTY
);
181 translate(SSH1_CMSG_WINDOW_SIZE
);
182 translate(SSH1_CMSG_EXEC_SHELL
);
183 translate(SSH1_CMSG_EXEC_CMD
);
184 translate(SSH1_SMSG_SUCCESS
);
185 translate(SSH1_SMSG_FAILURE
);
186 translate(SSH1_CMSG_STDIN_DATA
);
187 translate(SSH1_SMSG_STDOUT_DATA
);
188 translate(SSH1_SMSG_STDERR_DATA
);
189 translate(SSH1_CMSG_EOF
);
190 translate(SSH1_SMSG_EXIT_STATUS
);
191 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
);
192 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE
);
193 translate(SSH1_MSG_CHANNEL_DATA
);
194 translate(SSH1_MSG_CHANNEL_CLOSE
);
195 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
);
196 translate(SSH1_SMSG_X11_OPEN
);
197 translate(SSH1_CMSG_PORT_FORWARD_REQUEST
);
198 translate(SSH1_MSG_PORT_OPEN
);
199 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING
);
200 translate(SSH1_SMSG_AGENT_OPEN
);
201 translate(SSH1_MSG_IGNORE
);
202 translate(SSH1_CMSG_EXIT_CONFIRMATION
);
203 translate(SSH1_CMSG_X11_REQUEST_FORWARDING
);
204 translate(SSH1_CMSG_AUTH_RHOSTS_RSA
);
205 translate(SSH1_MSG_DEBUG
);
206 translate(SSH1_CMSG_REQUEST_COMPRESSION
);
207 translate(SSH1_CMSG_AUTH_TIS
);
208 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE
);
209 translate(SSH1_CMSG_AUTH_TIS_RESPONSE
);
210 translate(SSH1_CMSG_AUTH_CCARD
);
211 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE
);
212 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE
);
215 static char *ssh2_pkt_type(int pkt_ctx
, int type
)
217 translate(SSH2_MSG_DISCONNECT
);
218 translate(SSH2_MSG_IGNORE
);
219 translate(SSH2_MSG_UNIMPLEMENTED
);
220 translate(SSH2_MSG_DEBUG
);
221 translate(SSH2_MSG_SERVICE_REQUEST
);
222 translate(SSH2_MSG_SERVICE_ACCEPT
);
223 translate(SSH2_MSG_KEXINIT
);
224 translate(SSH2_MSG_NEWKEYS
);
225 translatec(SSH2_MSG_KEXDH_INIT
, SSH2_PKTCTX_DHGROUP
);
226 translatec(SSH2_MSG_KEXDH_REPLY
, SSH2_PKTCTX_DHGROUP
);
227 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST
, SSH2_PKTCTX_DHGEX
);
228 translatec(SSH2_MSG_KEX_DH_GEX_GROUP
, SSH2_PKTCTX_DHGEX
);
229 translatec(SSH2_MSG_KEX_DH_GEX_INIT
, SSH2_PKTCTX_DHGEX
);
230 translatec(SSH2_MSG_KEX_DH_GEX_REPLY
, SSH2_PKTCTX_DHGEX
);
231 translate(SSH2_MSG_USERAUTH_REQUEST
);
232 translate(SSH2_MSG_USERAUTH_FAILURE
);
233 translate(SSH2_MSG_USERAUTH_SUCCESS
);
234 translate(SSH2_MSG_USERAUTH_BANNER
);
235 translatec(SSH2_MSG_USERAUTH_PK_OK
, SSH2_PKTCTX_PUBLICKEY
);
236 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
, SSH2_PKTCTX_PASSWORD
);
237 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST
, SSH2_PKTCTX_KBDINTER
);
238 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE
, SSH2_PKTCTX_KBDINTER
);
239 translate(SSH2_MSG_GLOBAL_REQUEST
);
240 translate(SSH2_MSG_REQUEST_SUCCESS
);
241 translate(SSH2_MSG_REQUEST_FAILURE
);
242 translate(SSH2_MSG_CHANNEL_OPEN
);
243 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
244 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
245 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
246 translate(SSH2_MSG_CHANNEL_DATA
);
247 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA
);
248 translate(SSH2_MSG_CHANNEL_EOF
);
249 translate(SSH2_MSG_CHANNEL_CLOSE
);
250 translate(SSH2_MSG_CHANNEL_REQUEST
);
251 translate(SSH2_MSG_CHANNEL_SUCCESS
);
252 translate(SSH2_MSG_CHANNEL_FAILURE
);
258 #define GET_32BIT(cp) \
259 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
260 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
261 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
262 ((unsigned long)(unsigned char)(cp)[3]))
264 #define PUT_32BIT(cp, value) { \
265 (cp)[0] = (unsigned char)((value) >> 24); \
266 (cp)[1] = (unsigned char)((value) >> 16); \
267 (cp)[2] = (unsigned char)((value) >> 8); \
268 (cp)[3] = (unsigned char)(value); }
270 /* Enumeration values for fields in SSH-1 packets */
272 PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
,
273 /* These values are for communicating relevant semantics of
274 * fields to the packet logging code. */
275 PKTT_OTHER
, PKTT_PASSWORD
, PKTT_DATA
279 * Coroutine mechanics for the sillier bits of the code. If these
280 * macros look impenetrable to you, you might find it helpful to
283 * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
285 * which explains the theory behind these macros.
287 * In particular, if you are getting `case expression not constant'
288 * errors when building with MS Visual Studio, this is because MS's
289 * Edit and Continue debugging feature causes their compiler to
290 * violate ANSI C. To disable Edit and Continue debugging:
292 * - right-click ssh.c in the FileView
294 * - select the C/C++ tab and the General category
295 * - under `Debug info:', select anything _other_ than `Program
296 * Database for Edit and Continue'.
298 #define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
301 if (!ssh->t) ssh->t = snew(struct t); \
303 #define crFinish(z) } *crLine = 0; return (z); }
304 #define crFinishV } *crLine = 0; return; }
305 #define crReturn(z) \
307 *crLine =__LINE__; return (z); case __LINE__:;\
311 *crLine=__LINE__; return; case __LINE__:;\
313 #define crStop(z) do{ *crLine = 0; return (z); }while(0)
314 #define crStopV do{ *crLine = 0; return; }while(0)
315 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
316 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
318 typedef struct ssh_tag
*Ssh
;
321 static struct Packet
*ssh2_pkt_init(int pkt_type
);
322 static void ssh2_pkt_addbool(struct Packet
*, unsigned char value
);
323 static void ssh2_pkt_adduint32(struct Packet
*, unsigned long value
);
324 static void ssh2_pkt_addstring_start(struct Packet
*);
325 static void ssh2_pkt_addstring_str(struct Packet
*, char *data
);
326 static void ssh2_pkt_addstring_data(struct Packet
*, char *data
, int len
);
327 static void ssh2_pkt_addstring(struct Packet
*, char *data
);
328 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
);
329 static void ssh2_pkt_addmp(struct Packet
*, Bignum b
);
330 static int ssh2_pkt_construct(Ssh
, struct Packet
*);
331 static void ssh2_pkt_send(Ssh
, struct Packet
*);
332 static void ssh2_pkt_send_noqueue(Ssh
, struct Packet
*);
333 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
334 struct Packet
*pktin
);
335 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
336 struct Packet
*pktin
);
339 * Buffer management constants. There are several of these for
340 * various different purposes:
342 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
343 * on a local data stream before we throttle the whole SSH
344 * connection (in SSH1 only). Throttling the whole connection is
345 * pretty drastic so we set this high in the hope it won't
348 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
349 * on the SSH connection itself before we defensively throttle
350 * _all_ local data streams. This is pretty drastic too (though
351 * thankfully unlikely in SSH2 since the window mechanism should
352 * ensure that the server never has any need to throttle its end
353 * of the connection), so we set this high as well.
355 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
359 #define SSH1_BUFFER_LIMIT 32768
360 #define SSH_MAX_BACKLOG 32768
361 #define OUR_V2_WINSIZE 16384
363 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
365 static void *nullmac_make_context(void)
369 static void nullmac_free_context(void *handle
)
372 static void nullmac_key(void *handle
, unsigned char *key
)
375 static void nullmac_generate(void *handle
, unsigned char *blk
, int len
,
379 static int nullmac_verify(void *handle
, unsigned char *blk
, int len
,
384 const static struct ssh_mac ssh_mac_none
= {
385 nullmac_make_context
, nullmac_free_context
, nullmac_key
,
386 nullmac_generate
, nullmac_verify
, "none", 0
388 const static struct ssh_mac
*macs
[] = {
389 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
391 const static struct ssh_mac
*buggymacs
[] = {
392 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
395 static void *ssh_comp_none_init(void)
399 static void ssh_comp_none_cleanup(void *handle
)
402 static int ssh_comp_none_block(void *handle
, unsigned char *block
, int len
,
403 unsigned char **outblock
, int *outlen
)
407 static int ssh_comp_none_disable(void *handle
)
411 const static struct ssh_compress ssh_comp_none
= {
413 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
414 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
415 ssh_comp_none_disable
, NULL
417 extern const struct ssh_compress ssh_zlib
;
418 const static struct ssh_compress
*compressions
[] = {
419 &ssh_zlib
, &ssh_comp_none
422 enum { /* channel types */
427 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
431 * 2-3-4 tree storing channels.
434 Ssh ssh
; /* pointer back to main context */
435 unsigned remoteid
, localid
;
438 * In SSH1, this value contains four bits:
440 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
441 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
442 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
443 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
445 * A channel is completely finished with when all four bits are set.
449 struct ssh1_data_channel
{
452 struct ssh2_data_channel
{
454 unsigned remwindow
, remmaxpkt
;
459 struct ssh_agent_channel
{
460 unsigned char *message
;
461 unsigned char msglen
[4];
462 unsigned lensofar
, totallen
;
464 struct ssh_x11_channel
{
467 struct ssh_pfd_channel
{
474 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
475 * 2 use this structure in different ways, reflecting SSH 2's
476 * altogether saner approach to port forwarding.
478 * In SSH 1, you arrange a remote forwarding by sending the server
479 * the remote port number, and the local destination host:port.
480 * When a connection comes in, the server sends you back that
481 * host:port pair, and you connect to it. This is a ready-made
482 * security hole if you're not on the ball: a malicious server
483 * could send you back _any_ host:port pair, so if you trustingly
484 * connect to the address it gives you then you've just opened the
485 * entire inside of your corporate network just by connecting
486 * through it to a dodgy SSH server. Hence, we must store a list of
487 * host:port pairs we _are_ trying to forward to, and reject a
488 * connection request from the server if it's not in the list.
490 * In SSH 2, each side of the connection minds its own business and
491 * doesn't send unnecessary information to the other. You arrange a
492 * remote forwarding by sending the server just the remote port
493 * number. When a connection comes in, the server tells you which
494 * of its ports was connected to; and _you_ have to remember what
495 * local host:port pair went with that port number.
497 * Hence, in SSH 1 this structure is indexed by destination
498 * host:port pair, whereas in SSH 2 it is indexed by source port.
500 struct ssh_rportfwd
{
501 unsigned sport
, dport
;
509 unsigned long sequence
;
514 long encrypted_len
; /* for SSH2 total-size counting */
517 * State associated with packet logging
521 struct logblank_t
*blanks
;
524 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
525 struct Packet
*pktin
);
526 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
527 struct Packet
*pktin
);
528 static void ssh1_protocol_setup(Ssh ssh
);
529 static void ssh2_protocol_setup(Ssh ssh
);
530 static void ssh_size(void *handle
, int width
, int height
);
531 static void ssh_special(void *handle
, Telnet_Special
);
532 static int ssh2_try_send(struct ssh_channel
*c
);
533 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
534 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
535 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
536 static int ssh_sendbuffer(void *handle
);
537 static void ssh_do_close(Ssh ssh
);
538 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
);
539 static int ssh2_pkt_getbool(struct Packet
*pkt
);
540 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
);
541 static void ssh2_timer(void *ctx
, long now
);
542 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
,
543 struct Packet
*pktin
);
545 struct rdpkt1_state_tag
{
546 long len
, pad
, biglen
, to_read
;
547 unsigned long realcrc
, gotcrc
;
551 struct Packet
*pktin
;
554 struct rdpkt2_state_tag
{
555 long len
, pad
, payload
, packetlen
, maclen
;
558 unsigned long incoming_sequence
;
559 struct Packet
*pktin
;
562 typedef void (*handler_fn_t
)(Ssh ssh
, struct Packet
*pktin
);
563 typedef void (*chandler_fn_t
)(Ssh ssh
, struct Packet
*pktin
, void *ctx
);
565 struct queued_handler
;
566 struct queued_handler
{
568 chandler_fn_t handler
;
570 struct queued_handler
*next
;
574 const struct plug_function_table
*fn
;
575 /* the above field _must_ be first in the structure */
577 SHA_State exhash
, exhashbase
;
584 unsigned char session_key
[32];
586 int v1_remote_protoflags
;
587 int v1_local_protoflags
;
588 int agentfwd_enabled
;
591 const struct ssh_cipher
*cipher
;
594 const struct ssh2_cipher
*cscipher
, *sccipher
;
595 void *cs_cipher_ctx
, *sc_cipher_ctx
;
596 const struct ssh_mac
*csmac
, *scmac
;
597 void *cs_mac_ctx
, *sc_mac_ctx
;
598 const struct ssh_compress
*cscomp
, *sccomp
;
599 void *cs_comp_ctx
, *sc_comp_ctx
;
600 const struct ssh_kex
*kex
;
601 const struct ssh_signkey
*hostkey
;
602 unsigned char v2_session_id
[20];
608 int echoing
, editing
;
612 int ospeed
, ispeed
; /* temporaries */
613 int term_width
, term_height
;
615 tree234
*channels
; /* indexed by local id */
616 struct ssh_channel
*mainchan
; /* primary session channel */
623 SSH_STATE_BEFORE_SIZE
,
629 int size_needed
, eof_needed
;
631 struct Packet
**queue
;
632 int queuelen
, queuesize
;
634 unsigned char *deferred_send_data
;
635 int deferred_len
, deferred_size
;
638 * Gross hack: pscp will try to start SFTP but fall back to
639 * scp1 if that fails. This variable is the means by which
640 * scp.c can reach into the SSH code and find out which one it
646 * Used for username and password input.
648 char *userpass_input_buffer
;
649 int userpass_input_buflen
;
650 int userpass_input_bufpos
;
651 int userpass_input_echo
;
658 int v1_throttle_count
;
661 int v1_stdout_throttling
;
662 int v2_outgoing_sequence
;
664 int ssh1_rdpkt_crstate
;
665 int ssh2_rdpkt_crstate
;
666 int do_ssh_init_crstate
;
667 int ssh_gotdata_crstate
;
668 int do_ssh1_login_crstate
;
669 int do_ssh1_connection_crstate
;
670 int do_ssh2_transport_crstate
;
671 int do_ssh2_authconn_crstate
;
673 void *do_ssh_init_state
;
674 void *do_ssh1_login_state
;
675 void *do_ssh2_transport_state
;
676 void *do_ssh2_authconn_state
;
678 struct rdpkt1_state_tag rdpkt1_state
;
679 struct rdpkt2_state_tag rdpkt2_state
;
681 /* ssh1 and ssh2 use this for different things, but both use it */
682 int protocol_initial_phase_done
;
684 void (*protocol
) (Ssh ssh
, unsigned char *in
, int inlen
,
686 struct Packet
*(*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
689 * We maintain a full _copy_ of a Config structure here, not
690 * merely a pointer to it. That way, when we're passed a new
691 * one for reconfiguration, we can check the differences and
692 * potentially reconfigure port forwardings etc in mid-session.
697 * Used to transfer data back from async agent callbacks.
699 void *agent_response
;
700 int agent_response_len
;
703 * Dispatch table for packet types that we may have to deal
706 handler_fn_t packet_dispatch
[256];
709 * Queues of one-off handler functions for success/failure
710 * indications from a request.
712 struct queued_handler
*qhead
, *qtail
;
715 * This module deals with sending keepalives.
720 * Track incoming and outgoing data sizes and time, for
723 unsigned long incoming_data_size
, outgoing_data_size
, deferred_data_size
;
724 unsigned long max_data_size
;
729 #define logevent(s) logevent(ssh->frontend, s)
731 /* logevent, only printf-formatted. */
732 static void logeventf(Ssh ssh
, const char *fmt
, ...)
738 buf
= dupvprintf(fmt
, ap
);
744 #define bombout(msg) \
746 char *text = dupprintf msg; \
749 connection_fatal(ssh->frontend, "%s", text); \
753 /* Functions to leave bits out of the SSH packet log file. */
755 static void dont_log_password(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
757 if (ssh
->cfg
.logomitpass
)
758 pkt
->logmode
= blanktype
;
761 static void dont_log_data(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
763 if (ssh
->cfg
.logomitdata
)
764 pkt
->logmode
= blanktype
;
767 static void end_log_omission(Ssh ssh
, struct Packet
*pkt
)
769 pkt
->logmode
= PKTLOG_EMIT
;
772 static int ssh_channelcmp(void *av
, void *bv
)
774 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
775 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
776 if (a
->localid
< b
->localid
)
778 if (a
->localid
> b
->localid
)
782 static int ssh_channelfind(void *av
, void *bv
)
784 unsigned *a
= (unsigned *) av
;
785 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
793 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
795 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
796 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
798 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
799 return i
< 0 ?
-1 : +1;
800 if (a
->dport
> b
->dport
)
802 if (a
->dport
< b
->dport
)
807 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
809 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
810 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
812 if (a
->sport
> b
->sport
)
814 if (a
->sport
< b
->sport
)
819 static int alloc_channel_id(Ssh ssh
)
821 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
822 unsigned low
, high
, mid
;
824 struct ssh_channel
*c
;
827 * First-fit allocation of channel numbers: always pick the
828 * lowest unused one. To do this, binary-search using the
829 * counted B-tree to find the largest channel ID which is in a
830 * contiguous sequence from the beginning. (Precisely
831 * everything in that sequence must have ID equal to its tree
832 * index plus CHANNEL_NUMBER_OFFSET.)
834 tsize
= count234(ssh
->channels
);
838 while (high
- low
> 1) {
839 mid
= (high
+ low
) / 2;
840 c
= index234(ssh
->channels
, mid
);
841 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
842 low
= mid
; /* this one is fine */
844 high
= mid
; /* this one is past it */
847 * Now low points to either -1, or the tree index of the
848 * largest ID in the initial sequence.
851 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
852 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
854 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
857 static void c_write(Ssh ssh
, const char *buf
, int len
)
859 if ((flags
& FLAG_STDERR
)) {
861 for (i
= 0; i
< len
; i
++)
863 fputc(buf
[i
], stderr
);
866 from_backend(ssh
->frontend
, 1, buf
, len
);
869 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
872 for (i
= 0; i
< len
; i
++) {
874 c_write(ssh
, "\r\n", 2);
875 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
876 c_write(ssh
, buf
+ i
, 1);
880 static void c_write_str(Ssh ssh
, const char *buf
)
882 c_write(ssh
, buf
, strlen(buf
));
885 static void ssh_free_packet(struct Packet
*pkt
)
890 static struct Packet
*ssh_new_packet(void)
892 struct Packet
*pkt
= snew(struct Packet
);
896 pkt
->logmode
= PKTLOG_EMIT
;
904 * Collect incoming data in the incoming packet buffer.
905 * Decipher and verify the packet when it is completely read.
906 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
907 * Update the *data and *datalen variables.
908 * Return a Packet structure when a packet is completed.
910 static struct Packet
*ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
912 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
914 crBegin(ssh
->ssh1_rdpkt_crstate
);
916 st
->pktin
= ssh_new_packet();
919 st
->pktin
->length
= 0;
921 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
922 while ((*datalen
) == 0)
924 st
->len
= (st
->len
<< 8) + **data
;
925 (*data
)++, (*datalen
)--;
928 st
->pad
= 8 - (st
->len
% 8);
929 st
->biglen
= st
->len
+ st
->pad
;
930 st
->pktin
->length
= st
->len
- 5;
932 if (st
->biglen
< 0) {
933 bombout(("Extremely large packet length from server suggests"
934 " data stream corruption"));
935 ssh_free_packet(st
->pktin
);
939 st
->pktin
->maxlen
= st
->biglen
;
940 st
->pktin
->data
= snewn(st
->biglen
+ APIEXTRA
, unsigned char);
942 st
->to_read
= st
->biglen
;
943 st
->p
= st
->pktin
->data
;
944 while (st
->to_read
> 0) {
945 st
->chunk
= st
->to_read
;
946 while ((*datalen
) == 0)
948 if (st
->chunk
> (*datalen
))
949 st
->chunk
= (*datalen
);
950 memcpy(st
->p
, *data
, st
->chunk
);
952 *datalen
-= st
->chunk
;
954 st
->to_read
-= st
->chunk
;
957 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, st
->pktin
->data
,
959 bombout(("Network attack (CRC compensation) detected!"));
960 ssh_free_packet(st
->pktin
);
965 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, st
->pktin
->data
, st
->biglen
);
967 st
->realcrc
= crc32_compute(st
->pktin
->data
, st
->biglen
- 4);
968 st
->gotcrc
= GET_32BIT(st
->pktin
->data
+ st
->biglen
- 4);
969 if (st
->gotcrc
!= st
->realcrc
) {
970 bombout(("Incorrect CRC received on packet"));
971 ssh_free_packet(st
->pktin
);
975 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
976 st
->pktin
->savedpos
= 0;
978 if (ssh
->v1_compressing
) {
979 unsigned char *decompblk
;
981 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
982 st
->pktin
->body
- 1, st
->pktin
->length
+ 1,
983 &decompblk
, &decomplen
)) {
984 bombout(("Zlib decompression encountered invalid data"));
985 ssh_free_packet(st
->pktin
);
989 if (st
->pktin
->maxlen
< st
->pad
+ decomplen
) {
990 st
->pktin
->maxlen
= st
->pad
+ decomplen
;
991 st
->pktin
->data
= sresize(st
->pktin
->data
,
992 st
->pktin
->maxlen
+ APIEXTRA
,
994 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
997 memcpy(st
->pktin
->body
- 1, decompblk
, decomplen
);
999 st
->pktin
->length
= decomplen
- 1;
1002 st
->pktin
->type
= st
->pktin
->body
[-1];
1005 * Log incoming packet, possibly omitting sensitive fields.
1009 struct logblank_t blank
;
1010 if (ssh
->cfg
.logomitdata
) {
1011 int do_blank
= FALSE
, blank_prefix
= 0;
1012 /* "Session data" packets - omit the data field */
1013 if ((st
->pktin
->type
== SSH1_SMSG_STDOUT_DATA
) ||
1014 (st
->pktin
->type
== SSH1_SMSG_STDERR_DATA
)) {
1015 do_blank
= TRUE
; blank_prefix
= 0;
1016 } else if (st
->pktin
->type
== SSH1_MSG_CHANNEL_DATA
) {
1017 do_blank
= TRUE
; blank_prefix
= 4;
1020 blank
.offset
= blank_prefix
;
1021 blank
.len
= st
->pktin
->length
;
1022 blank
.type
= PKTLOG_OMIT
;
1026 log_packet(ssh
->logctx
,
1027 PKT_INCOMING
, st
->pktin
->type
,
1028 ssh1_pkt_type(st
->pktin
->type
),
1029 st
->pktin
->body
, st
->pktin
->length
,
1033 crFinish(st
->pktin
);
1036 static struct Packet
*ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1038 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1040 crBegin(ssh
->ssh2_rdpkt_crstate
);
1042 st
->pktin
= ssh_new_packet();
1044 st
->pktin
->type
= 0;
1045 st
->pktin
->length
= 0;
1047 st
->cipherblk
= ssh
->sccipher
->blksize
;
1050 if (st
->cipherblk
< 8)
1053 st
->pktin
->data
= snewn(st
->cipherblk
+ APIEXTRA
, unsigned char);
1056 * Acquire and decrypt the first block of the packet. This will
1057 * contain the length and padding details.
1059 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1060 while ((*datalen
) == 0)
1062 st
->pktin
->data
[st
->i
] = *(*data
)++;
1067 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1068 st
->pktin
->data
, st
->cipherblk
);
1071 * Now get the length and padding figures.
1073 st
->len
= GET_32BIT(st
->pktin
->data
);
1074 st
->pad
= st
->pktin
->data
[4];
1077 * _Completely_ silly lengths should be stomped on before they
1078 * do us any more damage.
1080 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
1081 bombout(("Incoming packet was garbled on decryption"));
1082 ssh_free_packet(st
->pktin
);
1087 * This enables us to deduce the payload length.
1089 st
->payload
= st
->len
- st
->pad
- 1;
1091 st
->pktin
->length
= st
->payload
+ 5;
1094 * So now we can work out the total packet length.
1096 st
->packetlen
= st
->len
+ 4;
1097 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1100 * Allocate memory for the rest of the packet.
1102 st
->pktin
->maxlen
= st
->packetlen
+ st
->maclen
;
1103 st
->pktin
->data
= sresize(st
->pktin
->data
,
1104 st
->pktin
->maxlen
+ APIEXTRA
,
1108 * Read and decrypt the remainder of the packet.
1110 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1112 while ((*datalen
) == 0)
1114 st
->pktin
->data
[st
->i
] = *(*data
)++;
1117 /* Decrypt everything _except_ the MAC. */
1119 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1120 st
->pktin
->data
+ st
->cipherblk
,
1121 st
->packetlen
- st
->cipherblk
);
1123 st
->pktin
->encrypted_len
= st
->packetlen
;
1129 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, st
->pktin
->data
, st
->len
+ 4,
1130 st
->incoming_sequence
)) {
1131 bombout(("Incorrect MAC received on packet"));
1132 ssh_free_packet(st
->pktin
);
1136 st
->pktin
->sequence
= st
->incoming_sequence
++;
1139 * Decompress packet payload.
1142 unsigned char *newpayload
;
1145 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1146 st
->pktin
->data
+ 5, st
->pktin
->length
- 5,
1147 &newpayload
, &newlen
)) {
1148 if (st
->pktin
->maxlen
< newlen
+ 5) {
1149 st
->pktin
->maxlen
= newlen
+ 5;
1150 st
->pktin
->data
= sresize(st
->pktin
->data
,
1151 st
->pktin
->maxlen
+ APIEXTRA
,
1154 st
->pktin
->length
= 5 + newlen
;
1155 memcpy(st
->pktin
->data
+ 5, newpayload
, newlen
);
1160 st
->pktin
->savedpos
= 6;
1161 st
->pktin
->body
= st
->pktin
->data
;
1162 st
->pktin
->type
= st
->pktin
->data
[5];
1165 * Log incoming packet, possibly omitting sensitive fields.
1169 struct logblank_t blank
;
1170 if (ssh
->cfg
.logomitdata
) {
1171 int do_blank
= FALSE
, blank_prefix
= 0;
1172 /* "Session data" packets - omit the data field */
1173 if (st
->pktin
->type
== SSH2_MSG_CHANNEL_DATA
) {
1174 do_blank
= TRUE
; blank_prefix
= 4;
1175 } else if (st
->pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1176 do_blank
= TRUE
; blank_prefix
= 8;
1179 blank
.offset
= blank_prefix
;
1180 blank
.len
= (st
->pktin
->length
-6) - blank_prefix
;
1181 blank
.type
= PKTLOG_OMIT
;
1185 log_packet(ssh
->logctx
, PKT_INCOMING
, st
->pktin
->type
,
1186 ssh2_pkt_type(ssh
->pkt_ctx
, st
->pktin
->type
),
1187 st
->pktin
->data
+6, st
->pktin
->length
-6,
1191 crFinish(st
->pktin
);
1194 static void ssh1_pktout_size(struct Packet
*pkt
, int len
)
1198 len
+= 5; /* type and CRC */
1199 pad
= 8 - (len
% 8);
1202 pkt
->length
= len
- 5;
1203 if (pkt
->maxlen
< biglen
) {
1204 pkt
->maxlen
= biglen
;
1205 pkt
->data
= sresize(pkt
->data
, biglen
+ 4 + APIEXTRA
, unsigned char);
1207 pkt
->body
= pkt
->data
+ 4 + pad
+ 1;
1210 static struct Packet
*s_wrpkt_start(int type
, int len
)
1212 struct Packet
*pkt
= ssh_new_packet();
1213 ssh1_pktout_size(pkt
, len
);
1215 /* Initialise log omission state */
1221 static int s_wrpkt_prepare(Ssh ssh
, struct Packet
*pkt
)
1227 * XXX various versions of SC (including 8.8.4) screw up the
1228 * register allocation in this function and use the same register
1229 * (D6) for len and as a temporary, with predictable results. The
1230 * following sledgehammer prevents this.
1236 pkt
->body
[-1] = pkt
->type
;
1239 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->type
,
1240 ssh1_pkt_type(pkt
->type
),
1241 pkt
->body
, pkt
->length
,
1242 pkt
->nblanks
, pkt
->blanks
);
1243 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1246 if (ssh
->v1_compressing
) {
1247 unsigned char *compblk
;
1249 zlib_compress_block(ssh
->cs_comp_ctx
,
1250 pkt
->body
- 1, pkt
->length
+ 1,
1251 &compblk
, &complen
);
1252 ssh1_pktout_size(pkt
, complen
- 1);
1253 memcpy(pkt
->body
- 1, compblk
, complen
);
1257 len
= pkt
->length
+ 5; /* type and CRC */
1258 pad
= 8 - (len
% 8);
1261 for (i
= 0; i
< pad
; i
++)
1262 pkt
->data
[i
+ 4] = random_byte();
1263 crc
= crc32_compute(pkt
->data
+ 4, biglen
- 4);
1264 PUT_32BIT(pkt
->data
+ biglen
, crc
);
1265 PUT_32BIT(pkt
->data
, len
);
1268 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, pkt
->data
+ 4, biglen
);
1273 static void s_wrpkt(Ssh ssh
, struct Packet
*pkt
)
1276 len
= s_wrpkt_prepare(ssh
, pkt
);
1277 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1278 if (backlog
> SSH_MAX_BACKLOG
)
1279 ssh_throttle_all(ssh
, 1, backlog
);
1282 static void s_wrpkt_defer(Ssh ssh
, struct Packet
*pkt
)
1285 len
= s_wrpkt_prepare(ssh
, pkt
);
1286 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1287 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1288 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1292 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1293 ssh
->deferred_len
+= len
;
1297 * Construct a packet with the specified contents.
1299 static struct Packet
*construct_packet(Ssh ssh
, int pkttype
,
1300 va_list ap1
, va_list ap2
)
1302 unsigned char *p
, *argp
, argchar
;
1303 unsigned long argint
;
1304 int pktlen
, argtype
, arglen
;
1309 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1312 (void) va_arg(ap1
, int);
1316 (void) va_arg(ap1
, int);
1320 (void) va_arg(ap1
, unsigned char *);
1321 arglen
= va_arg(ap1
, int);
1325 argp
= va_arg(ap1
, unsigned char *);
1326 arglen
= strlen((char *)argp
);
1327 pktlen
+= 4 + arglen
;
1330 bn
= va_arg(ap1
, Bignum
);
1331 pktlen
+= ssh1_bignum_length(bn
);
1336 /* ignore this pass */
1343 pkt
= s_wrpkt_start(pkttype
, pktlen
);
1346 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1347 int offset
= p
- pkt
->body
, len
= 0;
1349 /* Actual fields in the packet */
1351 argint
= va_arg(ap2
, int);
1352 PUT_32BIT(p
, argint
);
1356 argchar
= (unsigned char) va_arg(ap2
, int);
1361 argp
= va_arg(ap2
, unsigned char *);
1362 arglen
= va_arg(ap2
, int);
1363 memcpy(p
, argp
, arglen
);
1367 argp
= va_arg(ap2
, unsigned char *);
1368 arglen
= strlen((char *)argp
);
1369 PUT_32BIT(p
, arglen
);
1370 memcpy(p
+ 4, argp
, arglen
);
1374 bn
= va_arg(ap2
, Bignum
);
1375 len
= ssh1_write_bignum(p
, bn
);
1377 /* Tokens for modifications to packet logging */
1379 dont_log_password(ssh
, pkt
, PKTLOG_BLANK
);
1382 dont_log_data(ssh
, pkt
, PKTLOG_OMIT
);
1385 end_log_omission(ssh
, pkt
);
1389 /* Deal with logfile omission, if required. */
1390 if (len
&& (pkt
->logmode
!= PKTLOG_EMIT
)) {
1392 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
,
1394 pkt
->blanks
[pkt
->nblanks
-1].offset
= offset
;
1395 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1396 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1403 static void send_packet(Ssh ssh
, int pkttype
, ...)
1407 va_start(ap1
, pkttype
);
1408 va_start(ap2
, pkttype
);
1409 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1413 ssh_free_packet(pkt
);
1416 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1420 va_start(ap1
, pkttype
);
1421 va_start(ap2
, pkttype
);
1422 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1425 s_wrpkt_defer(ssh
, pkt
);
1426 ssh_free_packet(pkt
);
1429 static int ssh_versioncmp(char *a
, char *b
)
1432 unsigned long av
, bv
;
1434 av
= strtoul(a
, &ae
, 10);
1435 bv
= strtoul(b
, &be
, 10);
1437 return (av
< bv ?
-1 : +1);
1442 av
= strtoul(ae
, &ae
, 10);
1443 bv
= strtoul(be
, &be
, 10);
1445 return (av
< bv ?
-1 : +1);
1450 * Utility routines for putting an SSH-protocol `string' and
1451 * `uint32' into a SHA state.
1454 static void sha_string(SHA_State
* s
, void *str
, int len
)
1456 unsigned char lenblk
[4];
1457 PUT_32BIT(lenblk
, len
);
1458 SHA_Bytes(s
, lenblk
, 4);
1459 SHA_Bytes(s
, str
, len
);
1462 static void sha_uint32(SHA_State
* s
, unsigned i
)
1464 unsigned char intblk
[4];
1465 PUT_32BIT(intblk
, i
);
1466 SHA_Bytes(s
, intblk
, 4);
1470 * SSH2 packet construction functions.
1472 static void ssh2_pkt_ensure(struct Packet
*pkt
, int length
)
1474 if (pkt
->maxlen
< length
) {
1475 pkt
->maxlen
= length
+ 256;
1476 pkt
->data
= sresize(pkt
->data
, pkt
->maxlen
+ APIEXTRA
, unsigned char);
1479 static void ssh2_pkt_adddata(struct Packet
*pkt
, void *data
, int len
)
1481 if (pkt
->logmode
!= PKTLOG_EMIT
) {
1483 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
, struct logblank_t
);
1484 pkt
->blanks
[pkt
->nblanks
-1].offset
= pkt
->length
- 6;
1485 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1486 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1489 ssh2_pkt_ensure(pkt
, pkt
->length
);
1490 memcpy(pkt
->data
+ pkt
->length
- len
, data
, len
);
1492 static void ssh2_pkt_addbyte(struct Packet
*pkt
, unsigned char byte
)
1494 ssh2_pkt_adddata(pkt
, &byte
, 1);
1496 static struct Packet
*ssh2_pkt_init(int pkt_type
)
1498 struct Packet
*pkt
= ssh_new_packet();
1500 ssh2_pkt_addbyte(pkt
, (unsigned char) pkt_type
);
1503 static void ssh2_pkt_addbool(struct Packet
*pkt
, unsigned char value
)
1505 ssh2_pkt_adddata(pkt
, &value
, 1);
1507 static void ssh2_pkt_adduint32(struct Packet
*pkt
, unsigned long value
)
1510 PUT_32BIT(x
, value
);
1511 ssh2_pkt_adddata(pkt
, x
, 4);
1513 static void ssh2_pkt_addstring_start(struct Packet
*pkt
)
1515 ssh2_pkt_adduint32(pkt
, 0);
1516 pkt
->savedpos
= pkt
->length
;
1518 static void ssh2_pkt_addstring_str(struct Packet
*pkt
, char *data
)
1520 ssh2_pkt_adddata(pkt
, data
, strlen(data
));
1521 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1523 static void ssh2_pkt_addstring_data(struct Packet
*pkt
, char *data
, int len
)
1525 ssh2_pkt_adddata(pkt
, data
, len
);
1526 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1528 static void ssh2_pkt_addstring(struct Packet
*pkt
, char *data
)
1530 ssh2_pkt_addstring_start(pkt
);
1531 ssh2_pkt_addstring_str(pkt
, data
);
1533 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1536 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1537 p
= snewn(n
+ 1, unsigned char);
1539 fatalbox("out of memory");
1541 for (i
= 1; i
<= n
; i
++)
1542 p
[i
] = bignum_byte(b
, n
- i
);
1544 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1546 memmove(p
, p
+ i
, n
+ 1 - i
);
1550 static void ssh2_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1554 p
= ssh2_mpint_fmt(b
, &len
);
1555 ssh2_pkt_addstring_start(pkt
);
1556 ssh2_pkt_addstring_data(pkt
, (char *)p
, len
);
1561 * Construct an SSH2 final-form packet: compress it, encrypt it,
1562 * put the MAC on it. Final packet, ready to be sent, is stored in
1563 * pkt->data. Total length is returned.
1565 static int ssh2_pkt_construct(Ssh ssh
, struct Packet
*pkt
)
1567 int cipherblk
, maclen
, padding
, i
;
1570 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[5],
1571 ssh2_pkt_type(ssh
->pkt_ctx
, pkt
->data
[5]),
1572 pkt
->data
+ 6, pkt
->length
- 6,
1573 pkt
->nblanks
, pkt
->blanks
);
1574 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1578 * Compress packet payload.
1581 unsigned char *newpayload
;
1584 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, pkt
->data
+ 5,
1586 &newpayload
, &newlen
)) {
1588 ssh2_pkt_adddata(pkt
, newpayload
, newlen
);
1594 * Add padding. At least four bytes, and must also bring total
1595 * length (minus MAC) up to a multiple of the block size.
1597 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1598 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1601 (cipherblk
- (pkt
->length
+ padding
) % cipherblk
) % cipherblk
;
1602 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1603 ssh2_pkt_ensure(pkt
, pkt
->length
+ padding
+ maclen
);
1604 pkt
->data
[4] = padding
;
1605 for (i
= 0; i
< padding
; i
++)
1606 pkt
->data
[pkt
->length
+ i
] = random_byte();
1607 PUT_32BIT(pkt
->data
, pkt
->length
+ padding
- 4);
1609 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, pkt
->data
,
1610 pkt
->length
+ padding
,
1611 ssh
->v2_outgoing_sequence
);
1612 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1615 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1616 pkt
->data
, pkt
->length
+ padding
);
1618 pkt
->encrypted_len
= pkt
->length
+ padding
;
1620 /* Ready-to-send packet starts at pkt->data. We return length. */
1621 return pkt
->length
+ padding
+ maclen
;
1625 * Routines called from the main SSH code to send packets. There
1626 * are quite a few of these, because we have two separate
1627 * mechanisms for delaying the sending of packets:
1629 * - In order to send an IGNORE message and a password message in
1630 * a single fixed-length blob, we require the ability to
1631 * concatenate the encrypted forms of those two packets _into_ a
1632 * single blob and then pass it to our <network.h> transport
1633 * layer in one go. Hence, there's a deferment mechanism which
1634 * works after packet encryption.
1636 * - In order to avoid sending any connection-layer messages
1637 * during repeat key exchange, we have to queue up any such
1638 * outgoing messages _before_ they are encrypted (and in
1639 * particular before they're allocated sequence numbers), and
1640 * then send them once we've finished.
1642 * I call these mechanisms `defer' and `queue' respectively, so as
1643 * to distinguish them reasonably easily.
1645 * The functions send_noqueue() and defer_noqueue() free the packet
1646 * structure they are passed. Every outgoing packet goes through
1647 * precisely one of these functions in its life; packets passed to
1648 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1649 * these or get queued, and then when the queue is later emptied
1650 * the packets are all passed to defer_noqueue().
1654 * Send an SSH2 packet immediately, without queuing or deferring.
1656 static void ssh2_pkt_send_noqueue(Ssh ssh
, struct Packet
*pkt
)
1660 len
= ssh2_pkt_construct(ssh
, pkt
);
1661 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1662 if (backlog
> SSH_MAX_BACKLOG
)
1663 ssh_throttle_all(ssh
, 1, backlog
);
1665 ssh
->outgoing_data_size
+= pkt
->encrypted_len
;
1666 if (!ssh
->kex_in_progress
&&
1667 ssh
->max_data_size
!= 0 &&
1668 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1669 do_ssh2_transport(ssh
, "Initiating key re-exchange "
1670 "(too much data sent)", -1, NULL
);
1672 ssh_free_packet(pkt
);
1676 * Defer an SSH2 packet.
1678 static void ssh2_pkt_defer_noqueue(Ssh ssh
, struct Packet
*pkt
)
1680 int len
= ssh2_pkt_construct(ssh
, pkt
);
1681 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1682 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1683 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1687 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1688 ssh
->deferred_len
+= len
;
1689 ssh
->deferred_data_size
+= pkt
->encrypted_len
;
1690 ssh_free_packet(pkt
);
1694 * Queue an SSH2 packet.
1696 static void ssh2_pkt_queue(Ssh ssh
, struct Packet
*pkt
)
1698 assert(ssh
->queueing
);
1700 if (ssh
->queuelen
>= ssh
->queuesize
) {
1701 ssh
->queuesize
= ssh
->queuelen
+ 32;
1702 ssh
->queue
= sresize(ssh
->queue
, ssh
->queuesize
, struct Packet
*);
1705 ssh
->queue
[ssh
->queuelen
++] = pkt
;
1709 * Either queue or send a packet, depending on whether queueing is
1712 static void ssh2_pkt_send(Ssh ssh
, struct Packet
*pkt
)
1715 ssh2_pkt_queue(ssh
, pkt
);
1717 ssh2_pkt_send_noqueue(ssh
, pkt
);
1721 * Either queue or defer a packet, depending on whether queueing is
1724 static void ssh2_pkt_defer(Ssh ssh
, struct Packet
*pkt
)
1727 ssh2_pkt_queue(ssh
, pkt
);
1729 ssh2_pkt_defer_noqueue(ssh
, pkt
);
1733 * Send the whole deferred data block constructed by
1734 * ssh2_pkt_defer() or SSH1's defer_packet().
1736 * The expected use of the defer mechanism is that you call
1737 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1738 * not currently queueing, this simply sets up deferred_send_data
1739 * and then sends it. If we _are_ currently queueing, the calls to
1740 * ssh2_pkt_defer() put the deferred packets on to the queue
1741 * instead, and therefore ssh_pkt_defersend() has no deferred data
1742 * to send. Hence, there's no need to make it conditional on
1745 static void ssh_pkt_defersend(Ssh ssh
)
1748 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1750 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1751 sfree(ssh
->deferred_send_data
);
1752 ssh
->deferred_send_data
= NULL
;
1753 if (backlog
> SSH_MAX_BACKLOG
)
1754 ssh_throttle_all(ssh
, 1, backlog
);
1756 ssh
->outgoing_data_size
+= ssh
->deferred_data_size
;
1757 if (!ssh
->kex_in_progress
&&
1758 ssh
->max_data_size
!= 0 &&
1759 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1760 do_ssh2_transport(ssh
, "Initiating key re-exchange "
1761 "(too much data sent)", -1, NULL
);
1762 ssh
->deferred_data_size
= 0;
1766 * Send all queued SSH2 packets. We send them by means of
1767 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1768 * packets that needed to be lumped together.
1770 static void ssh2_pkt_queuesend(Ssh ssh
)
1774 assert(!ssh
->queueing
);
1776 for (i
= 0; i
< ssh
->queuelen
; i
++)
1777 ssh2_pkt_defer_noqueue(ssh
, ssh
->queue
[i
]);
1780 ssh_pkt_defersend(ssh
);
1784 void bndebug(char *string
, Bignum b
)
1788 p
= ssh2_mpint_fmt(b
, &len
);
1789 debug(("%s", string
));
1790 for (i
= 0; i
< len
; i
++)
1791 debug((" %02x", p
[i
]));
1797 static void sha_mpint(SHA_State
* s
, Bignum b
)
1801 p
= ssh2_mpint_fmt(b
, &len
);
1802 sha_string(s
, p
, len
);
1807 * Packet decode functions for both SSH1 and SSH2.
1809 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
)
1811 unsigned long value
;
1812 if (pkt
->length
- pkt
->savedpos
< 4)
1813 return 0; /* arrgh, no way to decline (FIXME?) */
1814 value
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1818 static int ssh2_pkt_getbool(struct Packet
*pkt
)
1820 unsigned long value
;
1821 if (pkt
->length
- pkt
->savedpos
< 1)
1822 return 0; /* arrgh, no way to decline (FIXME?) */
1823 value
= pkt
->body
[pkt
->savedpos
] != 0;
1827 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
)
1832 if (pkt
->length
- pkt
->savedpos
< 4)
1834 len
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1839 if (pkt
->length
- pkt
->savedpos
< *length
)
1841 *p
= (char *)(pkt
->body
+ pkt
->savedpos
);
1842 pkt
->savedpos
+= *length
;
1844 static void *ssh_pkt_getdata(struct Packet
*pkt
, int length
)
1846 if (pkt
->length
- pkt
->savedpos
< length
)
1848 pkt
->savedpos
+= length
;
1849 return pkt
->body
+ (pkt
->savedpos
- length
);
1851 static int ssh1_pkt_getrsakey(struct Packet
*pkt
, struct RSAKey
*key
,
1852 unsigned char **keystr
)
1856 j
= makekey(pkt
->body
+ pkt
->savedpos
,
1857 pkt
->length
- pkt
->savedpos
,
1864 assert(pkt
->savedpos
< pkt
->length
);
1868 static Bignum
ssh1_pkt_getmp(struct Packet
*pkt
)
1873 j
= ssh1_read_bignum(pkt
->body
+ pkt
->savedpos
,
1874 pkt
->length
- pkt
->savedpos
, &b
);
1882 static Bignum
ssh2_pkt_getmp(struct Packet
*pkt
)
1888 ssh_pkt_getstring(pkt
, &p
, &length
);
1893 b
= bignum_from_bytes((unsigned char *)p
, length
);
1898 * Helper function to add an SSH2 signature blob to a packet.
1899 * Expects to be shown the public key blob as well as the signature
1900 * blob. Normally works just like ssh2_pkt_addstring, but will
1901 * fiddle with the signature packet if necessary for
1902 * BUG_SSH2_RSA_PADDING.
1904 static void ssh2_add_sigblob(Ssh ssh
, struct Packet
*pkt
,
1905 void *pkblob_v
, int pkblob_len
,
1906 void *sigblob_v
, int sigblob_len
)
1908 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1909 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1911 /* dmemdump(pkblob, pkblob_len); */
1912 /* dmemdump(sigblob, sigblob_len); */
1915 * See if this is in fact an ssh-rsa signature and a buggy
1916 * server; otherwise we can just do this the easy way.
1918 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1919 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1920 int pos
, len
, siglen
;
1923 * Find the byte length of the modulus.
1926 pos
= 4+7; /* skip over "ssh-rsa" */
1927 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1928 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
1929 pos
+= 4; /* find modulus itself */
1930 while (len
> 0 && pkblob
[pos
] == 0)
1932 /* debug(("modulus length is %d\n", len)); */
1935 * Now find the signature integer.
1937 pos
= 4+7; /* skip over "ssh-rsa" */
1938 siglen
= GET_32BIT(sigblob
+pos
);
1939 /* debug(("signature length is %d\n", siglen)); */
1941 if (len
!= siglen
) {
1942 unsigned char newlen
[4];
1943 ssh2_pkt_addstring_start(pkt
);
1944 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, pos
);
1945 /* dmemdump(sigblob, pos); */
1946 pos
+= 4; /* point to start of actual sig */
1947 PUT_32BIT(newlen
, len
);
1948 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 4);
1949 /* dmemdump(newlen, 4); */
1951 while (len
-- > siglen
) {
1952 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 1);
1953 /* dmemdump(newlen, 1); */
1955 ssh2_pkt_addstring_data(pkt
, (char *)(sigblob
+pos
), siglen
);
1956 /* dmemdump(sigblob+pos, siglen); */
1960 /* Otherwise fall through and do it the easy way. */
1963 ssh2_pkt_addstring_start(pkt
);
1964 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, sigblob_len
);
1968 * Examine the remote side's version string and compare it against
1969 * a list of known buggy implementations.
1971 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
1973 char *imp
; /* pointer to implementation part */
1975 imp
+= strcspn(imp
, "-");
1977 imp
+= strcspn(imp
, "-");
1980 ssh
->remote_bugs
= 0;
1982 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
1983 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
1984 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
1985 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
1986 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
1987 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
1989 * These versions don't support SSH1_MSG_IGNORE, so we have
1990 * to use a different defence against password length
1993 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
1994 logevent("We believe remote version has SSH1 ignore bug");
1997 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
1998 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
1999 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
2001 * These versions need a plain password sent; they can't
2002 * handle having a null and a random length of data after
2005 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
2006 logevent("We believe remote version needs a plain SSH1 password");
2009 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
2010 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
2011 (!strcmp(imp
, "Cisco-1.25")))) {
2013 * These versions apparently have no clue whatever about
2014 * RSA authentication and will panic and die if they see
2015 * an AUTH_RSA message.
2017 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
2018 logevent("We believe remote version can't handle RSA authentication");
2021 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
2022 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
2023 !wc_match("* VShell", imp
) &&
2024 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
2025 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
2026 wc_match("2.1 *", imp
)))) {
2028 * These versions have the HMAC bug.
2030 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
2031 logevent("We believe remote version has SSH2 HMAC bug");
2034 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2035 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2036 !wc_match("* VShell", imp
) &&
2037 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2039 * These versions have the key-derivation bug (failing to
2040 * include the literal shared secret in the hashes that
2041 * generate the keys).
2043 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2044 logevent("We believe remote version has SSH2 key-derivation bug");
2047 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2048 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2049 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2050 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2052 * These versions have the SSH2 RSA padding bug.
2054 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2055 logevent("We believe remote version has SSH2 RSA padding bug");
2058 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2059 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2060 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2062 * These versions have the SSH2 session-ID bug in
2063 * public-key authentication.
2065 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2066 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2071 * The `software version' part of an SSH version string is required
2072 * to contain no spaces or minus signs.
2074 static void ssh_fix_verstring(char *str
)
2076 /* Eat "SSH-<protoversion>-". */
2077 assert(*str
== 'S'); str
++;
2078 assert(*str
== 'S'); str
++;
2079 assert(*str
== 'H'); str
++;
2080 assert(*str
== '-'); str
++;
2081 while (*str
&& *str
!= '-') str
++;
2082 assert(*str
== '-'); str
++;
2084 /* Convert minus signs and spaces in the remaining string into
2087 if (*str
== '-' || *str
== ' ')
2093 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2095 struct do_ssh_init_state
{
2103 crState(do_ssh_init_state
);
2105 crBegin(ssh
->do_ssh_init_crstate
);
2107 /* Search for the string "SSH-" in the input. */
2110 static const int transS
[] = { 1, 2, 2, 1 };
2111 static const int transH
[] = { 0, 0, 3, 0 };
2112 static const int transminus
[] = { 0, 0, 0, -1 };
2114 s
->i
= transS
[s
->i
];
2116 s
->i
= transH
[s
->i
];
2118 s
->i
= transminus
[s
->i
];
2123 crReturn(1); /* get another character */
2127 s
->vstring
= snewn(s
->vstrsize
, char);
2128 strcpy(s
->vstring
, "SSH-");
2132 crReturn(1); /* get another char */
2133 if (s
->vslen
>= s
->vstrsize
- 1) {
2135 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2137 s
->vstring
[s
->vslen
++] = c
;
2140 s
->version
[s
->i
] = '\0';
2142 } else if (s
->i
< sizeof(s
->version
) - 1)
2143 s
->version
[s
->i
++] = c
;
2144 } else if (c
== '\012')
2148 ssh
->agentfwd_enabled
= FALSE
;
2149 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2151 s
->vstring
[s
->vslen
] = 0;
2152 s
->vstring
[strcspn(s
->vstring
, "\015\012")] = '\0';/* remove EOL chars */
2155 vlog
= snewn(20 + s
->vslen
, char);
2156 sprintf(vlog
, "Server version: %s", s
->vstring
);
2160 ssh_detect_bugs(ssh
, s
->vstring
);
2163 * Decide which SSH protocol version to support.
2166 /* Anything strictly below "2.0" means protocol 1 is supported. */
2167 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2168 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2169 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2171 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2172 bombout(("SSH protocol version 1 required by user but not provided by server"));
2175 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2176 bombout(("SSH protocol version 2 required by user but not provided by server"));
2183 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2185 * Construct a v2 version string.
2187 verstring
= dupprintf("SSH-2.0-%s\015\012", sshver
);
2191 * Construct a v1 version string.
2193 verstring
= dupprintf("SSH-%s-%s\012",
2194 (ssh_versioncmp(s
->version
, "1.5") <= 0 ?
2195 s
->version
: "1.5"),
2200 ssh_fix_verstring(verstring
);
2202 if (ssh
->version
== 2) {
2204 * Hash our version string and their version string.
2206 SHA_Init(&ssh
->exhashbase
);
2207 sha_string(&ssh
->exhashbase
, verstring
,
2208 strcspn(verstring
, "\015\012"));
2209 sha_string(&ssh
->exhashbase
, s
->vstring
,
2210 strcspn(s
->vstring
, "\015\012"));
2213 * Initialise SSHv2 protocol.
2215 ssh
->protocol
= ssh2_protocol
;
2216 ssh2_protocol_setup(ssh
);
2217 ssh
->s_rdpkt
= ssh2_rdpkt
;
2220 * Initialise SSHv1 protocol.
2222 ssh
->protocol
= ssh1_protocol
;
2223 ssh1_protocol_setup(ssh
);
2224 ssh
->s_rdpkt
= ssh1_rdpkt
;
2226 logeventf(ssh
, "We claim version: %.*s",
2227 strcspn(verstring
, "\015\012"), verstring
);
2228 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2232 logeventf(ssh
, "Using SSH protocol version %d", ssh
->version
);
2234 update_specials_menu(ssh
->frontend
);
2235 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2236 ssh
->pinger
= pinger_new(&ssh
->cfg
, &ssh_backend
, ssh
);
2243 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2245 crBegin(ssh
->ssh_gotdata_crstate
);
2248 * To begin with, feed the characters one by one to the
2249 * protocol initialisation / selection function do_ssh_init().
2250 * When that returns 0, we're done with the initial greeting
2251 * exchange and can move on to packet discipline.
2254 int ret
; /* need not be kept across crReturn */
2256 crReturnV
; /* more data please */
2257 ret
= do_ssh_init(ssh
, *data
);
2265 * We emerge from that loop when the initial negotiation is
2266 * over and we have selected an s_rdpkt function. Now pass
2267 * everything to s_rdpkt, and then pass the resulting packets
2268 * to the proper protocol handler.
2273 while (datalen
> 0) {
2274 struct Packet
*pktin
= ssh
->s_rdpkt(ssh
, &data
, &datalen
);
2276 ssh
->protocol(ssh
, NULL
, 0, pktin
);
2277 ssh_free_packet(pktin
);
2279 if (ssh
->state
== SSH_STATE_CLOSED
)
2287 static void ssh_do_close(Ssh ssh
)
2290 struct ssh_channel
*c
;
2292 ssh
->state
= SSH_STATE_CLOSED
;
2296 notify_remote_exit(ssh
->frontend
);
2299 * Now we must shut down any port and X forwardings going
2300 * through this connection.
2302 if (ssh
->channels
) {
2303 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2306 x11_close(c
->u
.x11
.s
);
2309 pfd_close(c
->u
.pfd
.s
);
2312 del234(ssh
->channels
, c
);
2313 if (ssh
->version
== 2)
2314 bufchain_clear(&c
->v
.v2
.outbuffer
);
2320 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2323 Ssh ssh
= (Ssh
) plug
;
2326 /* A socket error has occurred. */
2327 logevent(error_msg
);
2328 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2330 /* Otherwise, the remote side closed the connection normally. */
2335 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2337 Ssh ssh
= (Ssh
) plug
;
2338 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2339 if (ssh
->state
== SSH_STATE_CLOSED
) {
2346 static void ssh_sent(Plug plug
, int bufsize
)
2348 Ssh ssh
= (Ssh
) plug
;
2350 * If the send backlog on the SSH socket itself clears, we
2351 * should unthrottle the whole world if it was throttled.
2353 if (bufsize
< SSH_MAX_BACKLOG
)
2354 ssh_throttle_all(ssh
, 0, bufsize
);
2358 * Connect to specified host and port.
2359 * Returns an error message, or NULL on success.
2360 * Also places the canonical host name into `realhost'. It must be
2361 * freed by the caller.
2363 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2364 char **realhost
, int nodelay
, int keepalive
)
2366 static const struct plug_function_table fn_table
= {
2376 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2377 if (!ssh
->savedhost
)
2378 fatalbox("Out of memory");
2379 strcpy(ssh
->savedhost
, host
);
2382 port
= 22; /* default ssh port */
2383 ssh
->savedport
= port
;
2388 logeventf(ssh
, "Looking up host \"%s\"", host
);
2389 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
);
2390 if ((err
= sk_addr_error(addr
)) != NULL
) {
2400 sk_getaddr(addr
, addrbuf
, 100);
2401 logeventf(ssh
, "Connecting to %s port %d", addrbuf
, port
);
2403 ssh
->fn
= &fn_table
;
2404 ssh
->s
= new_connection(addr
, *realhost
, port
,
2405 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2406 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2408 notify_remote_exit(ssh
->frontend
);
2416 * Throttle or unthrottle the SSH connection.
2418 static void ssh1_throttle(Ssh ssh
, int adjust
)
2420 int old_count
= ssh
->v1_throttle_count
;
2421 ssh
->v1_throttle_count
+= adjust
;
2422 assert(ssh
->v1_throttle_count
>= 0);
2423 if (ssh
->v1_throttle_count
&& !old_count
) {
2424 sk_set_frozen(ssh
->s
, 1);
2425 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2426 sk_set_frozen(ssh
->s
, 0);
2431 * Throttle or unthrottle _all_ local data streams (for when sends
2432 * on the SSH connection itself back up).
2434 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2437 struct ssh_channel
*c
;
2439 if (enable
== ssh
->throttled_all
)
2441 ssh
->throttled_all
= enable
;
2442 ssh
->overall_bufsize
= bufsize
;
2445 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2447 case CHAN_MAINSESSION
:
2449 * This is treated separately, outside the switch.
2453 x11_override_throttle(c
->u
.x11
.s
, enable
);
2456 /* Agent channels require no buffer management. */
2459 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2466 * Username and password input, abstracted off into routines
2467 * reusable in several places - even between SSH1 and SSH2.
2470 /* Set up a username or password input loop on a given buffer. */
2471 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2473 ssh
->userpass_input_buffer
= buffer
;
2474 ssh
->userpass_input_buflen
= buflen
;
2475 ssh
->userpass_input_bufpos
= 0;
2476 ssh
->userpass_input_echo
= echo
;
2480 * Process some terminal data in the course of username/password
2481 * input. Returns >0 for success (line of input returned in
2482 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2483 * for inconclusive (keep waiting for more input please).
2485 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2490 switch (c
= *in
++) {
2493 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2494 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2499 if (ssh
->userpass_input_bufpos
> 0) {
2500 if (ssh
->userpass_input_echo
)
2501 c_write_str(ssh
, "\b \b");
2502 ssh
->userpass_input_bufpos
--;
2507 while (ssh
->userpass_input_bufpos
> 0) {
2508 if (ssh
->userpass_input_echo
)
2509 c_write_str(ssh
, "\b \b");
2510 ssh
->userpass_input_bufpos
--;
2519 * This simplistic check for printability is disabled
2520 * when we're doing password input, because some people
2521 * have control characters in their passwords.o
2523 if ((!ssh
->userpass_input_echo
||
2524 (c
>= ' ' && c
<= '~') ||
2525 ((unsigned char) c
>= 160))
2526 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2527 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2528 if (ssh
->userpass_input_echo
)
2529 c_write(ssh
, &c
, 1);
2537 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2539 Ssh ssh
= (Ssh
) sshv
;
2541 ssh
->agent_response
= reply
;
2542 ssh
->agent_response_len
= replylen
;
2544 if (ssh
->version
== 1)
2545 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2547 do_ssh2_authconn(ssh
, NULL
, -1, NULL
);
2550 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2552 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2554 void *sentreply
= reply
;
2557 /* Fake SSH_AGENT_FAILURE. */
2558 sentreply
= "\0\0\0\1\5";
2561 if (ssh
->version
== 2) {
2562 ssh2_add_channel_data(c
, sentreply
, replylen
);
2565 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2566 PKT_INT
, c
->remoteid
,
2569 PKT_DATA
, sentreply
, replylen
,
2578 * Handle the key exchange and user authentication phases.
2580 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
2581 struct Packet
*pktin
)
2584 unsigned char cookie
[8], *ptr
;
2585 struct RSAKey servkey
, hostkey
;
2586 struct MD5Context md5c
;
2587 struct do_ssh1_login_state
{
2589 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2590 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2591 int tried_publickey
, tried_agent
;
2592 int tis_auth_refused
, ccard_auth_refused
;
2593 unsigned char session_id
[16];
2596 void *publickey_blob
;
2597 int publickey_bloblen
;
2603 unsigned char request
[5], *response
, *p
;
2612 crState(do_ssh1_login_state
);
2614 crBegin(ssh
->do_ssh1_login_crstate
);
2619 if (pktin
->type
!= SSH1_SMSG_PUBLIC_KEY
) {
2620 bombout(("Public key packet not received"));
2624 logevent("Received public keys");
2626 ptr
= ssh_pkt_getdata(pktin
, 8);
2628 bombout(("SSH1 public key packet stopped before random cookie"));
2631 memcpy(cookie
, ptr
, 8);
2633 if (!ssh1_pkt_getrsakey(pktin
, &servkey
, &s
->keystr1
) ||
2634 !ssh1_pkt_getrsakey(pktin
, &hostkey
, &s
->keystr2
)) {
2635 bombout(("Failed to read SSH1 public keys from public key packet"));
2640 * Log the host key fingerprint.
2644 logevent("Host key fingerprint is:");
2645 strcpy(logmsg
, " ");
2646 hostkey
.comment
= NULL
;
2647 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2648 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2652 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(pktin
);
2653 s
->supported_ciphers_mask
= ssh_pkt_getuint32(pktin
);
2654 s
->supported_auths_mask
= ssh_pkt_getuint32(pktin
);
2656 ssh
->v1_local_protoflags
=
2657 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2658 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2661 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2662 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2663 MD5Update(&md5c
, cookie
, 8);
2664 MD5Final(s
->session_id
, &md5c
);
2666 for (i
= 0; i
< 32; i
++)
2667 ssh
->session_key
[i
] = random_byte();
2670 * Verify that the `bits' and `bytes' parameters match.
2672 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
2673 servkey
.bits
> servkey
.bytes
* 8) {
2674 bombout(("SSH1 public keys were badly formatted"));
2678 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2680 s
->rsabuf
= snewn(s
->len
, unsigned char);
2682 fatalbox("Out of memory");
2685 * Verify the host key.
2689 * First format the key into a string.
2691 int len
= rsastr_len(&hostkey
);
2692 char fingerprint
[100];
2693 char *keystr
= snewn(len
, char);
2695 fatalbox("Out of memory");
2696 rsastr_fmt(keystr
, &hostkey
);
2697 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2698 verify_ssh_host_key(ssh
->frontend
,
2699 ssh
->savedhost
, ssh
->savedport
, "rsa", keystr
,
2704 for (i
= 0; i
< 32; i
++) {
2705 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2707 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2710 if (hostkey
.bytes
> servkey
.bytes
) {
2711 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
2713 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2715 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2717 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2720 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2724 logevent("Encrypted session key");
2727 int cipher_chosen
= 0, warn
= 0;
2728 char *cipher_string
= NULL
;
2730 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2731 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
2732 if (next_cipher
== CIPHER_WARN
) {
2733 /* If/when we choose a cipher, warn about it */
2735 } else if (next_cipher
== CIPHER_AES
) {
2736 /* XXX Probably don't need to mention this. */
2737 logevent("AES not supported in SSH1, skipping");
2739 switch (next_cipher
) {
2740 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2741 cipher_string
= "3DES"; break;
2742 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2743 cipher_string
= "Blowfish"; break;
2744 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2745 cipher_string
= "single-DES"; break;
2747 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2751 if (!cipher_chosen
) {
2752 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2753 bombout(("Server violates SSH 1 protocol by not "
2754 "supporting 3DES encryption"));
2756 /* shouldn't happen */
2757 bombout(("No supported ciphers found"));
2761 /* Warn about chosen cipher if necessary. */
2763 askalg(ssh
->frontend
, "cipher", cipher_string
);
2766 switch (s
->cipher_type
) {
2767 case SSH_CIPHER_3DES
:
2768 logevent("Using 3DES encryption");
2770 case SSH_CIPHER_DES
:
2771 logevent("Using single-DES encryption");
2773 case SSH_CIPHER_BLOWFISH
:
2774 logevent("Using Blowfish encryption");
2778 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
2779 PKT_CHAR
, s
->cipher_type
,
2780 PKT_DATA
, cookie
, 8,
2781 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
2782 PKT_DATA
, s
->rsabuf
, s
->len
,
2783 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
2785 logevent("Trying to enable encryption...");
2789 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2790 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
2792 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
2793 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
2794 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
2796 ssh
->crcda_ctx
= crcda_make_context();
2797 logevent("Installing CRC compensation attack detector");
2799 if (servkey
.modulus
) {
2800 sfree(servkey
.modulus
);
2801 servkey
.modulus
= NULL
;
2803 if (servkey
.exponent
) {
2804 sfree(servkey
.exponent
);
2805 servkey
.exponent
= NULL
;
2807 if (hostkey
.modulus
) {
2808 sfree(hostkey
.modulus
);
2809 hostkey
.modulus
= NULL
;
2811 if (hostkey
.exponent
) {
2812 sfree(hostkey
.exponent
);
2813 hostkey
.exponent
= NULL
;
2817 if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
2818 bombout(("Encryption not successfully enabled"));
2822 logevent("Successfully started encryption");
2826 if (!*ssh
->cfg
.username
) {
2827 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2828 if (!ssh_get_line("login as: ",
2829 s
->username
, sizeof(s
->username
), FALSE
)) {
2831 * get_line failed to get a username.
2834 logevent("No username provided. Abandoning session.");
2835 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2839 int ret
; /* need not be kept over crReturn */
2840 c_write_str(ssh
, "login as: ");
2843 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
2845 crWaitUntil(!pktin
);
2846 ret
= process_userpass_input(ssh
, in
, inlen
);
2850 c_write_str(ssh
, "\r\n");
2853 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
2854 s
->username
[sizeof(s
->username
)-1] = '\0';
2857 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
2859 char userlog
[22 + sizeof(s
->username
)];
2860 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
2862 if (flags
& FLAG_INTERACTIVE
&&
2863 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2864 strcat(userlog
, "\r\n");
2865 c_write_str(ssh
, userlog
);
2872 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2873 /* We must not attempt PK auth. Pretend we've already tried it. */
2874 s
->tried_publickey
= s
->tried_agent
= 1;
2876 s
->tried_publickey
= s
->tried_agent
= 0;
2878 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
2879 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
2880 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
2881 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
2882 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
2883 s
->publickey_blob
= NULL
;
2885 s
->publickey_blob
= NULL
;
2887 while (pktin
->type
== SSH1_SMSG_FAILURE
) {
2888 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2890 if (agent_exists() && !s
->tried_agent
) {
2892 * Attempt RSA authentication using Pageant.
2898 logevent("Pageant is running. Requesting keys.");
2900 /* Request the keys held by the agent. */
2901 PUT_32BIT(s
->request
, 1);
2902 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2903 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
2904 ssh_agent_callback
, ssh
)) {
2908 bombout(("Unexpected data from server while waiting"
2909 " for agent response"));
2912 } while (pktin
|| inlen
> 0);
2913 r
= ssh
->agent_response
;
2914 s
->responselen
= ssh
->agent_response_len
;
2916 s
->response
= (unsigned char *) r
;
2917 if (s
->response
&& s
->responselen
>= 5 &&
2918 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
2919 s
->p
= s
->response
+ 5;
2920 s
->nkeys
= GET_32BIT(s
->p
);
2924 sprintf(buf
, "Pageant has %d SSH1 keys", s
->nkeys
);
2927 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
2930 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
2933 if (s
->publickey_blob
&&
2934 !memcmp(s
->p
, s
->publickey_blob
,
2935 s
->publickey_bloblen
)) {
2936 logevent("This key matches configured key file");
2937 s
->tried_publickey
= 1;
2942 do { /* do while (0) to make breaking easy */
2943 n
= ssh1_read_bignum
2944 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
2949 n
= ssh1_read_bignum
2950 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
2955 if (s
->responselen
- (s
->p
-s
->response
) < 4)
2957 s
->commentlen
= GET_32BIT(s
->p
);
2959 if (s
->responselen
- (s
->p
-s
->response
) <
2962 s
->commentp
= (char *)s
->p
;
2963 s
->p
+= s
->commentlen
;
2967 logevent("Pageant key list packet was truncated");
2971 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
2972 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
2974 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2975 logevent("Key refused");
2978 logevent("Received RSA challenge");
2979 if ((s
->challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
2980 bombout(("Server's RSA challenge was badly formatted"));
2985 char *agentreq
, *q
, *ret
;
2988 len
= 1 + 4; /* message type, bit count */
2989 len
+= ssh1_bignum_length(s
->key
.exponent
);
2990 len
+= ssh1_bignum_length(s
->key
.modulus
);
2991 len
+= ssh1_bignum_length(s
->challenge
);
2992 len
+= 16; /* session id */
2993 len
+= 4; /* response format */
2994 agentreq
= snewn(4 + len
, char);
2995 PUT_32BIT(agentreq
, len
);
2997 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
2998 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
3000 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
3001 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
3002 q
+= ssh1_write_bignum(q
, s
->challenge
);
3003 memcpy(q
, s
->session_id
, 16);
3005 PUT_32BIT(q
, 1); /* response format */
3006 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
3007 ssh_agent_callback
, ssh
)) {
3012 bombout(("Unexpected data from server"
3013 " while waiting for agent"
3017 } while (pktin
|| inlen
> 0);
3018 vret
= ssh
->agent_response
;
3019 retlen
= ssh
->agent_response_len
;
3024 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
3025 logevent("Sending Pageant's response");
3026 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3027 PKT_DATA
, ret
+ 5, 16,
3031 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
3033 ("Pageant's response accepted");
3034 if (flags
& FLAG_VERBOSE
) {
3035 c_write_str(ssh
, "Authenticated using"
3037 c_write(ssh
, s
->commentp
,
3039 c_write_str(ssh
, "\" from agent\r\n");
3044 ("Pageant's response not accepted");
3047 ("Pageant failed to answer challenge");
3051 logevent("No reply received from Pageant");
3054 freebn(s
->key
.exponent
);
3055 freebn(s
->key
.modulus
);
3056 freebn(s
->challenge
);
3065 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
3066 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
3068 if (ssh
->cfg
.try_tis_auth
&&
3069 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3070 !s
->tis_auth_refused
) {
3071 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3072 logevent("Requested TIS authentication");
3073 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3075 if (pktin
->type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3076 logevent("TIS authentication declined");
3077 if (flags
& FLAG_INTERACTIVE
)
3078 c_write_str(ssh
, "TIS authentication refused.\r\n");
3079 s
->tis_auth_refused
= 1;
3085 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3087 bombout(("TIS challenge packet was badly formed"));
3090 logevent("Received TIS challenge");
3091 if (challengelen
> sizeof(s
->prompt
) - 1)
3092 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3093 memcpy(s
->prompt
, challenge
, challengelen
);
3094 /* Prompt heuristic comes from OpenSSH */
3095 strncpy(s
->prompt
+ challengelen
,
3096 memchr(s
->prompt
, '\n', challengelen
) ?
3097 "": "\r\nResponse: ",
3098 (sizeof s
->prompt
) - challengelen
);
3099 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
3102 if (ssh
->cfg
.try_tis_auth
&&
3103 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3104 !s
->ccard_auth_refused
) {
3105 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3106 logevent("Requested CryptoCard authentication");
3107 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3109 if (pktin
->type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3110 logevent("CryptoCard authentication declined");
3111 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3112 s
->ccard_auth_refused
= 1;
3118 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3120 bombout(("CryptoCard challenge packet was badly formed"));
3123 logevent("Received CryptoCard challenge");
3124 if (challengelen
> sizeof(s
->prompt
) - 1)
3125 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3126 memcpy(s
->prompt
, challenge
, challengelen
);
3127 strncpy(s
->prompt
+ challengelen
,
3128 memchr(s
->prompt
, '\n', challengelen
) ?
3129 "" : "\r\nResponse: ",
3130 sizeof(s
->prompt
) - challengelen
);
3131 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
3134 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3135 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
3136 s
->username
, ssh
->savedhost
);
3138 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3139 char *comment
= NULL
;
3142 if (flags
& FLAG_VERBOSE
)
3143 c_write_str(ssh
, "Trying public key authentication.\r\n");
3144 logeventf(ssh
, "Trying public key \"%s\"",
3145 filename_to_str(&ssh
->cfg
.keyfile
));
3146 type
= key_type(&ssh
->cfg
.keyfile
);
3147 if (type
!= SSH_KEYTYPE_SSH1
) {
3148 sprintf(msgbuf
, "Key is of wrong type (%s)",
3149 key_type_to_str(type
));
3151 c_write_str(ssh
, msgbuf
);
3152 c_write_str(ssh
, "\r\n");
3153 s
->tried_publickey
= 1;
3156 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
3157 if (flags
& FLAG_VERBOSE
)
3158 c_write_str(ssh
, "No passphrase required.\r\n");
3161 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
3166 * Show password prompt, having first obtained it via a TIS
3167 * or CryptoCard exchange if we're doing TIS or CryptoCard
3171 if (!ssh_get_line(s
->prompt
, s
->password
,
3172 sizeof(s
->password
), TRUE
)) {
3174 * get_line failed to get a password (for example
3175 * because one was supplied on the command line
3176 * which has already failed to work). Terminate.
3178 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
3179 PKT_STR
, "No more passwords available to try",
3181 logevent("Unable to authenticate");
3182 connection_fatal(ssh
->frontend
, "Unable to authenticate");
3183 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3187 /* Prompt may have come from server. We've munged it a bit, so
3188 * we know it to be zero-terminated at least once. */
3189 int ret
; /* need not be saved over crReturn */
3190 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3193 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3195 crWaitUntil(!pktin
);
3196 ret
= process_userpass_input(ssh
, in
, inlen
);
3200 c_write_str(ssh
, "\r\n");
3204 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3206 * Try public key authentication with the specified
3209 s
->tried_publickey
= 1;
3212 const char *error
= NULL
;
3213 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3216 c_write_str(ssh
, "Couldn't load private key from ");
3217 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3218 c_write_str(ssh
, " (");
3219 c_write_str(ssh
, error
);
3220 c_write_str(ssh
, ").\r\n");
3221 continue; /* go and try password */
3224 c_write_str(ssh
, "Wrong passphrase.\r\n");
3225 s
->tried_publickey
= 0;
3226 continue; /* try again */
3231 * Send a public key attempt.
3233 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3234 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3237 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3238 c_write_str(ssh
, "Server refused our public key.\r\n");
3239 continue; /* go and try password */
3241 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3242 bombout(("Bizarre response to offer of public key"));
3248 unsigned char buffer
[32];
3249 Bignum challenge
, response
;
3251 if ((challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3252 bombout(("Server's RSA challenge was badly formatted"));
3255 response
= rsadecrypt(challenge
, &s
->key
);
3256 freebn(s
->key
.private_exponent
);/* burn the evidence */
3258 for (i
= 0; i
< 32; i
++) {
3259 buffer
[i
] = bignum_byte(response
, 31 - i
);
3263 MD5Update(&md5c
, buffer
, 32);
3264 MD5Update(&md5c
, s
->session_id
, 16);
3265 MD5Final(buffer
, &md5c
);
3267 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3268 PKT_DATA
, buffer
, 16, PKT_END
);
3275 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3276 if (flags
& FLAG_VERBOSE
)
3277 c_write_str(ssh
, "Failed to authenticate with"
3278 " our public key.\r\n");
3279 continue; /* go and try password */
3280 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3281 bombout(("Bizarre response to RSA authentication response"));
3285 break; /* we're through! */
3287 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3289 * Defence against traffic analysis: we send a
3290 * whole bunch of packets containing strings of
3291 * different lengths. One of these strings is the
3292 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3293 * The others are all random data in
3294 * SSH1_MSG_IGNORE packets. This way a passive
3295 * listener can't tell which is the password, and
3296 * hence can't deduce the password length.
3298 * Anybody with a password length greater than 16
3299 * bytes is going to have enough entropy in their
3300 * password that a listener won't find it _that_
3301 * much help to know how long it is. So what we'll
3304 * - if password length < 16, we send 15 packets
3305 * containing string lengths 1 through 15
3307 * - otherwise, we let N be the nearest multiple
3308 * of 8 below the password length, and send 8
3309 * packets containing string lengths N through
3310 * N+7. This won't obscure the order of
3311 * magnitude of the password length, but it will
3312 * introduce a bit of extra uncertainty.
3314 * A few servers (the old 1.2.18 through 1.2.22)
3315 * can't deal with SSH1_MSG_IGNORE. For these
3316 * servers, we need an alternative defence. We make
3317 * use of the fact that the password is interpreted
3318 * as a C string: so we can append a NUL, then some
3321 * One server (a Cisco one) can deal with neither
3322 * SSH1_MSG_IGNORE _nor_ a padded password string.
3323 * For this server we are left with no defences
3324 * against password length sniffing.
3326 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3328 * The server can deal with SSH1_MSG_IGNORE, so
3329 * we can use the primary defence.
3331 int bottom
, top
, pwlen
, i
;
3334 pwlen
= strlen(s
->password
);
3336 bottom
= 0; /* zero length passwords are OK! :-) */
3339 bottom
= pwlen
& ~7;
3343 assert(pwlen
>= bottom
&& pwlen
<= top
);
3345 randomstr
= snewn(top
+ 1, char);
3347 for (i
= bottom
; i
<= top
; i
++) {
3349 defer_packet(ssh
, s
->pwpkt_type
,
3350 PKTT_PASSWORD
, PKT_STR
, s
->password
,
3351 PKTT_OTHER
, PKT_END
);
3353 for (j
= 0; j
< i
; j
++) {
3355 randomstr
[j
] = random_byte();
3356 } while (randomstr
[j
] == '\0');
3358 randomstr
[i
] = '\0';
3359 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3360 PKT_STR
, randomstr
, PKT_END
);
3363 logevent("Sending password with camouflage packets");
3364 ssh_pkt_defersend(ssh
);
3367 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3369 * The server can't deal with SSH1_MSG_IGNORE
3370 * but can deal with padded passwords, so we
3371 * can use the secondary defence.
3377 len
= strlen(s
->password
);
3378 if (len
< sizeof(string
)) {
3380 strcpy(string
, s
->password
);
3381 len
++; /* cover the zero byte */
3382 while (len
< sizeof(string
)) {
3383 string
[len
++] = (char) random_byte();
3388 logevent("Sending length-padded password");
3389 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3390 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3391 PKTT_OTHER
, PKT_END
);
3394 * The server has _both_
3395 * BUG_CHOKES_ON_SSH1_IGNORE and
3396 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3397 * therefore nothing we can do.
3400 len
= strlen(s
->password
);
3401 logevent("Sending unpadded password");
3402 send_packet(ssh
, s
->pwpkt_type
,
3403 PKTT_PASSWORD
, PKT_INT
, len
,
3404 PKT_DATA
, s
->password
, len
,
3405 PKTT_OTHER
, PKT_END
);
3408 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3409 PKT_STR
, s
->password
, PKTT_OTHER
, PKT_END
);
3412 logevent("Sent password");
3413 memset(s
->password
, 0, strlen(s
->password
));
3415 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3416 if (flags
& FLAG_VERBOSE
)
3417 c_write_str(ssh
, "Access denied\r\n");
3418 logevent("Authentication refused");
3419 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3420 bombout(("Strange packet received, type %d", pktin
->type
));
3425 logevent("Authentication successful");
3430 void sshfwd_close(struct ssh_channel
*c
)
3434 if (ssh
->state
!= SSH_STATE_SESSION
) {
3435 assert(ssh
->state
== SSH_STATE_CLOSED
);
3439 if (c
&& !c
->closes
) {
3441 * If the channel's remoteid is -1, we have sent
3442 * CHANNEL_OPEN for this channel, but it hasn't even been
3443 * acknowledged by the server. So we must set a close flag
3444 * on it now, and then when the server acks the channel
3445 * open, we can close it then.
3447 if (((int)c
->remoteid
) != -1) {
3448 if (ssh
->version
== 1) {
3449 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3452 struct Packet
*pktout
;
3453 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3454 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
3455 ssh2_pkt_send(ssh
, pktout
);
3458 c
->closes
= 1; /* sent MSG_CLOSE */
3459 if (c
->type
== CHAN_X11
) {
3461 logevent("Forwarded X11 connection terminated");
3462 } else if (c
->type
== CHAN_SOCKDATA
||
3463 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3465 logevent("Forwarded port closed");
3470 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3474 if (ssh
->state
!= SSH_STATE_SESSION
) {
3475 assert(ssh
->state
== SSH_STATE_CLOSED
);
3479 if (ssh
->version
== 1) {
3480 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3481 PKT_INT
, c
->remoteid
,
3483 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3484 PKTT_OTHER
, PKT_END
);
3486 * In SSH1 we can return 0 here - implying that forwarded
3487 * connections are never individually throttled - because
3488 * the only circumstance that can cause throttling will be
3489 * the whole SSH connection backing up, in which case
3490 * _everything_ will be throttled as a whole.
3494 ssh2_add_channel_data(c
, buf
, len
);
3495 return ssh2_try_send(c
);
3499 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3503 if (ssh
->state
!= SSH_STATE_SESSION
) {
3504 assert(ssh
->state
== SSH_STATE_CLOSED
);
3508 if (ssh
->version
== 1) {
3509 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3510 c
->v
.v1
.throttling
= 0;
3511 ssh1_throttle(ssh
, -1);
3514 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3518 static void ssh_queueing_handler(Ssh ssh
, struct Packet
*pktin
)
3520 struct queued_handler
*qh
= ssh
->qhead
;
3524 assert(pktin
->type
== qh
->msg1
|| pktin
->type
== qh
->msg2
);
3527 assert(ssh
->packet_dispatch
[qh
->msg1
] == ssh_queueing_handler
);
3528 ssh
->packet_dispatch
[qh
->msg1
] = NULL
;
3531 assert(ssh
->packet_dispatch
[qh
->msg2
] == ssh_queueing_handler
);
3532 ssh
->packet_dispatch
[qh
->msg2
] = NULL
;
3536 ssh
->qhead
= qh
->next
;
3538 if (ssh
->qhead
->msg1
> 0) {
3539 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg1
] == NULL
);
3540 ssh
->packet_dispatch
[ssh
->qhead
->msg1
] = ssh_queueing_handler
;
3542 if (ssh
->qhead
->msg2
> 0) {
3543 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg2
] == NULL
);
3544 ssh
->packet_dispatch
[ssh
->qhead
->msg2
] = ssh_queueing_handler
;
3547 ssh
->qhead
= ssh
->qtail
= NULL
;
3548 ssh
->packet_dispatch
[pktin
->type
] = NULL
;
3551 qh
->handler(ssh
, pktin
, qh
->ctx
);
3556 static void ssh_queue_handler(Ssh ssh
, int msg1
, int msg2
,
3557 chandler_fn_t handler
, void *ctx
)
3559 struct queued_handler
*qh
;
3561 qh
= snew(struct queued_handler
);
3564 qh
->handler
= handler
;
3568 if (ssh
->qtail
== NULL
) {
3572 assert(ssh
->packet_dispatch
[qh
->msg1
] == NULL
);
3573 ssh
->packet_dispatch
[qh
->msg1
] = ssh_queueing_handler
;
3576 assert(ssh
->packet_dispatch
[qh
->msg2
] == NULL
);
3577 ssh
->packet_dispatch
[qh
->msg2
] = ssh_queueing_handler
;
3580 ssh
->qtail
->next
= qh
;
3585 static void ssh_rportfwd_succfail(Ssh ssh
, struct Packet
*pktin
, void *ctx
)
3587 struct ssh_rportfwd
*rpf
, *pf
= (struct ssh_rportfwd
*)ctx
;
3589 if (pktin
->type
== (ssh
->version
== 1 ? SSH1_SMSG_SUCCESS
:
3590 SSH2_MSG_REQUEST_SUCCESS
)) {
3591 logeventf(ssh
, "Remote port forwarding from %s enabled",
3594 logeventf(ssh
, "Remote port forwarding from %s refused",
3597 rpf
= del234(ssh
->rportfwds
, pf
);
3599 sfree(pf
->sportdesc
);
3604 static void ssh_setup_portfwd(Ssh ssh
, const Config
*cfg
)
3608 int sport
,dport
,sserv
,dserv
;
3609 char sports
[256], dports
[256], saddr
[256], host
[256];
3610 const char *portfwd_strptr
;
3612 portfwd_strptr
= cfg
->portfwd
;
3614 while (*portfwd_strptr
) {
3615 type
= *portfwd_strptr
++;
3618 while (*portfwd_strptr
&& *portfwd_strptr
!= '\t') {
3619 if (*portfwd_strptr
== ':') {
3621 * We've seen a colon in the middle of the
3622 * source port number. This means that
3623 * everything we've seen until now is the
3624 * source _address_, so we'll move it into
3625 * saddr and start sports from the beginning
3630 if (ssh
->version
== 1 && type
== 'R') {
3631 logeventf(ssh
, "SSH1 cannot handle remote source address "
3632 "spec \"%s\"; ignoring", sports
);
3634 strcpy(saddr
, sports
);
3637 if (n
< 255) sports
[n
++] = *portfwd_strptr
++;
3641 if (*portfwd_strptr
== '\t')
3644 while (*portfwd_strptr
&& *portfwd_strptr
!= ':') {
3645 if (n
< 255) host
[n
++] = *portfwd_strptr
++;
3648 if (*portfwd_strptr
== ':')
3651 while (*portfwd_strptr
) {
3652 if (n
< 255) dports
[n
++] = *portfwd_strptr
++;
3656 dport
= atoi(dports
);
3660 dport
= net_service_lookup(dports
);
3662 logeventf(ssh
, "Service lookup failed for destination"
3663 " port \"%s\"", dports
);
3667 while (*portfwd_strptr
) portfwd_strptr
++;
3669 portfwd_strptr
++; /* eat the NUL and move to next one */
3671 sport
= atoi(sports
);
3675 sport
= net_service_lookup(sports
);
3677 logeventf(ssh
, "Service lookup failed for source"
3678 " port \"%s\"", sports
);
3681 if (sport
&& dport
) {
3682 /* Set up a description of the source port. */
3683 static char *sportdesc
;
3684 sportdesc
= dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
3685 (int)(*saddr?
strlen(saddr
):0), *saddr?saddr
:NULL
,
3686 (int)(*saddr?
1:0), ":",
3687 (int)(sserv ?
strlen(sports
) : 0), sports
,
3688 sserv
, "(", sport
, sserv
, ")");
3690 /* Verbose description of the destination port */
3691 char *dportdesc
= dupprintf("%s:%.*s%.*s%d%.*s",
3693 (int)(dserv ?
strlen(dports
) : 0), dports
,
3694 dserv
, "(", dport
, dserv
, ")");
3695 const char *err
= pfd_addforward(host
, dport
,
3696 *saddr ? saddr
: NULL
,
3697 sport
, ssh
, &ssh
->cfg
);
3699 logeventf(ssh
, "Local port %s forward to %s"
3700 " failed: %s", sportdesc
, dportdesc
, err
);
3702 logeventf(ssh
, "Local port %s forwarding to %s",
3703 sportdesc
, dportdesc
);
3706 } else if (type
== 'D') {
3707 const char *err
= pfd_addforward(NULL
, -1,
3708 *saddr ? saddr
: NULL
,
3709 sport
, ssh
, &ssh
->cfg
);
3711 logeventf(ssh
, "Local port %s SOCKS dynamic forward"
3712 " setup failed: %s", sportdesc
, err
);
3714 logeventf(ssh
, "Local port %s doing SOCKS"
3715 " dynamic forwarding", sportdesc
);
3718 struct ssh_rportfwd
*pf
;
3721 * Ensure the remote port forwardings tree exists.
3723 if (!ssh
->rportfwds
) {
3724 if (ssh
->version
== 1)
3725 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3727 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
3730 pf
= snew(struct ssh_rportfwd
);
3731 strcpy(pf
->dhost
, host
);
3734 if (add234(ssh
->rportfwds
, pf
) != pf
) {
3735 logeventf(ssh
, "Duplicate remote port forwarding to %s:%d",
3739 logeventf(ssh
, "Requesting remote port %s"
3740 " forward to %s:%.*s%.*s%d%.*s",
3742 (int)(dserv ?
strlen(dports
) : 0), dports
,
3743 dserv
, "(", dport
, dserv
, ")");
3745 pf
->sportdesc
= sportdesc
;
3748 if (ssh
->version
== 1) {
3749 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
3754 ssh_queue_handler(ssh
, SSH1_SMSG_SUCCESS
,
3756 ssh_rportfwd_succfail
, pf
);
3758 struct Packet
*pktout
;
3759 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
3760 ssh2_pkt_addstring(pktout
, "tcpip-forward");
3761 ssh2_pkt_addbool(pktout
, 1);/* want reply */
3763 ssh2_pkt_addstring(pktout
, saddr
);
3764 } else if (ssh
->cfg
.rport_acceptall
) {
3765 ssh2_pkt_addstring(pktout
, "0.0.0.0");
3767 ssh2_pkt_addstring(pktout
, "127.0.0.1");
3769 ssh2_pkt_adduint32(pktout
, sport
);
3770 ssh2_pkt_send(ssh
, pktout
);
3772 ssh_queue_handler(ssh
, SSH2_MSG_REQUEST_SUCCESS
,
3773 SSH2_MSG_REQUEST_FAILURE
,
3774 ssh_rportfwd_succfail
, pf
);
3783 static void ssh1_smsg_stdout_stderr_data(Ssh ssh
, struct Packet
*pktin
)
3786 int stringlen
, bufsize
;
3788 ssh_pkt_getstring(pktin
, &string
, &stringlen
);
3789 if (string
== NULL
) {
3790 bombout(("Incoming terminal data packet was badly formed"));
3794 bufsize
= from_backend(ssh
->frontend
, pktin
->type
== SSH1_SMSG_STDERR_DATA
,
3796 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3797 ssh
->v1_stdout_throttling
= 1;
3798 ssh1_throttle(ssh
, +1);
3802 static void ssh1_smsg_x11_open(Ssh ssh
, struct Packet
*pktin
)
3804 /* Remote side is trying to open a channel to talk to our
3805 * X-Server. Give them back a local channel number. */
3806 struct ssh_channel
*c
;
3807 int remoteid
= ssh_pkt_getuint32(pktin
);
3809 logevent("Received X11 connect request");
3810 /* Refuse if X11 forwarding is disabled. */
3811 if (!ssh
->X11_fwd_enabled
) {
3812 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3813 PKT_INT
, remoteid
, PKT_END
);
3814 logevent("Rejected X11 connect request");
3816 c
= snew(struct ssh_channel
);
3819 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
3820 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
3821 logevent("Opening X11 forward connection failed");
3823 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3824 PKT_INT
, remoteid
, PKT_END
);
3827 ("Opening X11 forward connection succeeded");
3828 c
->remoteid
= remoteid
;
3829 c
->localid
= alloc_channel_id(ssh
);
3831 c
->v
.v1
.throttling
= 0;
3832 c
->type
= CHAN_X11
; /* identify channel type */
3833 add234(ssh
->channels
, c
);
3834 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3835 PKT_INT
, c
->remoteid
, PKT_INT
,
3836 c
->localid
, PKT_END
);
3837 logevent("Opened X11 forward channel");
3842 static void ssh1_smsg_agent_open(Ssh ssh
, struct Packet
*pktin
)
3844 /* Remote side is trying to open a channel to talk to our
3845 * agent. Give them back a local channel number. */
3846 struct ssh_channel
*c
;
3847 int remoteid
= ssh_pkt_getuint32(pktin
);
3849 /* Refuse if agent forwarding is disabled. */
3850 if (!ssh
->agentfwd_enabled
) {
3851 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3852 PKT_INT
, remoteid
, PKT_END
);
3854 c
= snew(struct ssh_channel
);
3856 c
->remoteid
= remoteid
;
3857 c
->localid
= alloc_channel_id(ssh
);
3859 c
->v
.v1
.throttling
= 0;
3860 c
->type
= CHAN_AGENT
; /* identify channel type */
3861 c
->u
.a
.lensofar
= 0;
3862 add234(ssh
->channels
, c
);
3863 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3864 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
3869 static void ssh1_msg_port_open(Ssh ssh
, struct Packet
*pktin
)
3871 /* Remote side is trying to open a channel to talk to a
3872 * forwarded port. Give them back a local channel number. */
3873 struct ssh_channel
*c
;
3874 struct ssh_rportfwd pf
;
3877 char *host
, buf
[1024];
3879 c
= snew(struct ssh_channel
);
3882 remoteid
= ssh_pkt_getuint32(pktin
);
3883 ssh_pkt_getstring(pktin
, &host
, &hostsize
);
3884 port
= ssh_pkt_getuint32(pktin
);
3886 if (hostsize
>= lenof(pf
.dhost
))
3887 hostsize
= lenof(pf
.dhost
)-1;
3888 memcpy(pf
.dhost
, host
, hostsize
);
3889 pf
.dhost
[hostsize
] = '\0';
3892 if (find234(ssh
->rportfwds
, &pf
, NULL
) == NULL
) {
3893 sprintf(buf
, "Rejected remote port open request for %s:%d",
3896 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3897 PKT_INT
, remoteid
, PKT_END
);
3899 sprintf(buf
, "Received remote port open request for %s:%d",
3902 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
3906 sprintf(buf
, "Port open failed: %s", e
);
3909 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3910 PKT_INT
, remoteid
, PKT_END
);
3912 c
->remoteid
= remoteid
;
3913 c
->localid
= alloc_channel_id(ssh
);
3915 c
->v
.v1
.throttling
= 0;
3916 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
3917 add234(ssh
->channels
, c
);
3918 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3919 PKT_INT
, c
->remoteid
, PKT_INT
,
3920 c
->localid
, PKT_END
);
3921 logevent("Forwarded port opened successfully");
3926 static void ssh1_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
3928 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
3929 unsigned int localid
= ssh_pkt_getuint32(pktin
);
3930 struct ssh_channel
*c
;
3932 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
3933 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3934 c
->remoteid
= localid
;
3935 c
->type
= CHAN_SOCKDATA
;
3936 c
->v
.v1
.throttling
= 0;
3937 pfd_confirm(c
->u
.pfd
.s
);
3940 if (c
&& c
->closes
) {
3942 * We have a pending close on this channel,
3943 * which we decided on before the server acked
3944 * the channel open. So now we know the
3945 * remoteid, we can close it again.
3947 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
3948 PKT_INT
, c
->remoteid
, PKT_END
);
3952 static void ssh1_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
3954 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
3955 struct ssh_channel
*c
;
3957 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
3958 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3959 logevent("Forwarded connection refused by server");
3960 pfd_close(c
->u
.pfd
.s
);
3961 del234(ssh
->channels
, c
);
3966 static void ssh1_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
3968 /* Remote side closes a channel. */
3969 unsigned i
= ssh_pkt_getuint32(pktin
);
3970 struct ssh_channel
*c
;
3971 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
3972 if (c
&& ((int)c
->remoteid
) != -1) {
3975 (pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
3977 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
3978 logevent("Forwarded X11 connection terminated");
3979 assert(c
->u
.x11
.s
!= NULL
);
3980 x11_close(c
->u
.x11
.s
);
3983 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
3984 logevent("Forwarded port closed");
3985 assert(c
->u
.pfd
.s
!= NULL
);
3986 pfd_close(c
->u
.pfd
.s
);
3990 c
->closes
|= (closetype
<< 2); /* seen this message */
3991 if (!(c
->closes
& closetype
)) {
3992 send_packet(ssh
, pktin
->type
, PKT_INT
, c
->remoteid
,
3994 c
->closes
|= closetype
; /* sent it too */
3997 if (c
->closes
== 15) {
3998 del234(ssh
->channels
, c
);
4002 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4003 pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
4004 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
4009 static void ssh1_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
4011 /* Data sent down one of our channels. */
4012 int i
= ssh_pkt_getuint32(pktin
);
4015 struct ssh_channel
*c
;
4017 ssh_pkt_getstring(pktin
, &p
, &len
);
4019 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4024 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
4027 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
4030 /* Data for an agent message. Buffer it. */
4032 if (c
->u
.a
.lensofar
< 4) {
4033 int l
= min(4 - c
->u
.a
.lensofar
, len
);
4034 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
4038 c
->u
.a
.lensofar
+= l
;
4040 if (c
->u
.a
.lensofar
== 4) {
4042 4 + GET_32BIT(c
->u
.a
.msglen
);
4043 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
4045 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
4047 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
4049 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
4051 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
4055 c
->u
.a
.lensofar
+= l
;
4057 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
4060 if (agent_query(c
->u
.a
.message
,
4063 ssh_agentf_callback
, c
))
4064 ssh_agentf_callback(c
, reply
, replylen
);
4065 sfree(c
->u
.a
.message
);
4066 c
->u
.a
.lensofar
= 0;
4069 bufsize
= 0; /* agent channels never back up */
4072 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4073 c
->v
.v1
.throttling
= 1;
4074 ssh1_throttle(ssh
, +1);
4079 static void ssh1_smsg_exit_status(Ssh ssh
, struct Packet
*pktin
)
4082 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
4083 sprintf(buf
, "Server sent command exit status %d",
4086 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
4088 * In case `helpful' firewalls or proxies tack
4089 * extra human-readable text on the end of the
4090 * session which we might mistake for another
4091 * encrypted packet, we close the session once
4092 * we've sent EXIT_CONFIRMATION.
4094 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4097 static void do_ssh1_connection(Ssh ssh
, unsigned char *in
, int inlen
,
4098 struct Packet
*pktin
)
4100 crBegin(ssh
->do_ssh1_connection_crstate
);
4102 ssh
->packet_dispatch
[SSH1_SMSG_STDOUT_DATA
] =
4103 ssh
->packet_dispatch
[SSH1_SMSG_STDERR_DATA
] =
4104 ssh1_smsg_stdout_stderr_data
;
4106 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
] =
4107 ssh1_msg_channel_open_confirmation
;
4108 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_FAILURE
] =
4109 ssh1_msg_channel_open_failure
;
4110 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE
] =
4111 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
] =
4112 ssh1_msg_channel_close
;
4113 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_DATA
] = ssh1_msg_channel_data
;
4114 ssh
->packet_dispatch
[SSH1_SMSG_EXIT_STATUS
] = ssh1_smsg_exit_status
;
4116 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
4117 logevent("Requesting agent forwarding");
4118 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
4122 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4123 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4124 bombout(("Protocol confusion"));
4126 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4127 logevent("Agent forwarding refused");
4129 logevent("Agent forwarding enabled");
4130 ssh
->agentfwd_enabled
= TRUE
;
4131 ssh
->packet_dispatch
[SSH1_SMSG_AGENT_OPEN
] = ssh1_smsg_agent_open
;
4135 if (ssh
->cfg
.x11_forward
) {
4136 char proto
[20], data
[64];
4137 logevent("Requesting X11 forwarding");
4138 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
4139 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
4140 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
4141 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
4142 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4143 PKT_STR
, proto
, PKT_STR
, data
,
4144 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
4147 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4148 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
4153 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4154 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4155 bombout(("Protocol confusion"));
4157 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4158 logevent("X11 forwarding refused");
4160 logevent("X11 forwarding enabled");
4161 ssh
->X11_fwd_enabled
= TRUE
;
4162 ssh
->packet_dispatch
[SSH1_SMSG_X11_OPEN
] = ssh1_smsg_x11_open
;
4166 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
4167 ssh
->packet_dispatch
[SSH1_MSG_PORT_OPEN
] = ssh1_msg_port_open
;
4169 if (!ssh
->cfg
.nopty
) {
4170 /* Unpick the terminal-speed string. */
4171 /* XXX perhaps we should allow no speeds to be sent. */
4172 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
4173 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
4174 /* Send the pty request. */
4175 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
4176 PKT_STR
, ssh
->cfg
.termtype
,
4177 PKT_INT
, ssh
->term_height
,
4178 PKT_INT
, ssh
->term_width
,
4179 PKT_INT
, 0, PKT_INT
, 0, /* width,height in pixels */
4180 PKT_CHAR
, 192, PKT_INT
, ssh
->ispeed
, /* TTY_OP_ISPEED */
4181 PKT_CHAR
, 193, PKT_INT
, ssh
->ospeed
, /* TTY_OP_OSPEED */
4182 PKT_CHAR
, 0, PKT_END
);
4183 ssh
->state
= SSH_STATE_INTERMED
;
4187 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4188 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4189 bombout(("Protocol confusion"));
4191 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4192 c_write_str(ssh
, "Server refused to allocate pty\r\n");
4193 ssh
->editing
= ssh
->echoing
= 1;
4195 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
4196 ssh
->ospeed
, ssh
->ispeed
);
4198 ssh
->editing
= ssh
->echoing
= 1;
4201 if (ssh
->cfg
.compression
) {
4202 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
4206 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4207 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4208 bombout(("Protocol confusion"));
4210 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4211 c_write_str(ssh
, "Server refused to compress\r\n");
4213 logevent("Started compression");
4214 ssh
->v1_compressing
= TRUE
;
4215 ssh
->cs_comp_ctx
= zlib_compress_init();
4216 logevent("Initialised zlib (RFC1950) compression");
4217 ssh
->sc_comp_ctx
= zlib_decompress_init();
4218 logevent("Initialised zlib (RFC1950) decompression");
4222 * Start the shell or command.
4224 * Special case: if the first-choice command is an SSH2
4225 * subsystem (hence not usable here) and the second choice
4226 * exists, we fall straight back to that.
4229 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
4231 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
4232 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
4233 ssh
->fallback_cmd
= TRUE
;
4236 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
4238 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
4239 logevent("Started session");
4242 ssh
->state
= SSH_STATE_SESSION
;
4243 if (ssh
->size_needed
)
4244 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
4245 if (ssh
->eof_needed
)
4246 ssh_special(ssh
, TS_EOF
);
4249 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
4251 ssh
->channels
= newtree234(ssh_channelcmp
);
4255 * By this point, most incoming packets are already being
4256 * handled by the dispatch table, and we need only pay
4257 * attention to the unusual ones.
4262 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
4263 /* may be from EXEC_SHELL on some servers */
4264 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4265 /* may be from EXEC_SHELL on some servers
4266 * if no pty is available or in other odd cases. Ignore */
4268 bombout(("Strange packet received: type %d", pktin
->type
));
4273 int len
= min(inlen
, 512);
4274 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4275 PKT_INT
, len
, PKT_DATA
, in
, len
,
4276 PKTT_OTHER
, PKT_END
);
4287 * Handle the top-level SSH2 protocol.
4289 static void ssh1_msg_debug(Ssh ssh
, struct Packet
*pktin
)
4294 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4295 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
4300 static void ssh1_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
4302 /* log reason code in disconnect message */
4306 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4307 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen
, msg
));
4310 void ssh_msg_ignore(Ssh ssh
, struct Packet
*pktin
)
4312 /* Do nothing, because we're ignoring it! Duhh. */
4315 static void ssh1_protocol_setup(Ssh ssh
)
4320 * Most messages are handled by the coroutines.
4322 for (i
= 0; i
< 256; i
++)
4323 ssh
->packet_dispatch
[i
] = NULL
;
4326 * These special message types we install handlers for.
4328 ssh
->packet_dispatch
[SSH1_MSG_DISCONNECT
] = ssh1_msg_disconnect
;
4329 ssh
->packet_dispatch
[SSH1_MSG_IGNORE
] = ssh_msg_ignore
;
4330 ssh
->packet_dispatch
[SSH1_MSG_DEBUG
] = ssh1_msg_debug
;
4333 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
4334 struct Packet
*pktin
)
4336 if (ssh
->state
== SSH_STATE_CLOSED
)
4339 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
4340 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
4344 if (!ssh
->protocol_initial_phase_done
) {
4345 if (do_ssh1_login(ssh
, in
, inlen
, pktin
))
4346 ssh
->protocol_initial_phase_done
= TRUE
;
4351 do_ssh1_connection(ssh
, in
, inlen
, pktin
);
4355 * Utility routine for decoding comma-separated strings in KEXINIT.
4357 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
4360 if (!needle
|| !haystack
) /* protect against null pointers */
4362 needlen
= strlen(needle
);
4365 * Is it at the start of the string?
4367 if (haylen
>= needlen
&& /* haystack is long enough */
4368 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4369 (haylen
== needlen
|| haystack
[needlen
] == ',')
4370 /* either , or EOS follows */
4374 * If not, search for the next comma and resume after that.
4375 * If no comma found, terminate.
4377 while (haylen
> 0 && *haystack
!= ',')
4378 haylen
--, haystack
++;
4381 haylen
--, haystack
++; /* skip over comma itself */
4386 * SSH2 key creation method.
4388 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
4389 unsigned char *sessid
, char chr
,
4390 unsigned char *keyspace
)
4393 /* First 20 bytes. */
4395 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4397 SHA_Bytes(&s
, H
, 20);
4398 SHA_Bytes(&s
, &chr
, 1);
4399 SHA_Bytes(&s
, sessid
, 20);
4400 SHA_Final(&s
, keyspace
);
4401 /* Next 20 bytes. */
4403 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4405 SHA_Bytes(&s
, H
, 20);
4406 SHA_Bytes(&s
, keyspace
, 20);
4407 SHA_Final(&s
, keyspace
+ 20);
4411 * Handle the SSH2 transport layer.
4413 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
,
4414 struct Packet
*pktin
)
4416 struct do_ssh2_transport_state
{
4417 int nbits
, pbits
, warn
;
4418 Bignum p
, g
, e
, f
, K
;
4419 int kex_init_value
, kex_reply_value
;
4420 const struct ssh_mac
**maclist
;
4422 const struct ssh2_cipher
*cscipher_tobe
;
4423 const struct ssh2_cipher
*sccipher_tobe
;
4424 const struct ssh_mac
*csmac_tobe
;
4425 const struct ssh_mac
*scmac_tobe
;
4426 const struct ssh_compress
*cscomp_tobe
;
4427 const struct ssh_compress
*sccomp_tobe
;
4428 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4429 int hostkeylen
, siglen
;
4430 void *hkey
; /* actual host key */
4431 unsigned char exchange_hash
[20];
4432 int n_preferred_kex
;
4433 const struct ssh_kex
*preferred_kex
[KEX_MAX
];
4434 int n_preferred_ciphers
;
4435 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
4436 const struct ssh_compress
*preferred_comp
;
4438 struct Packet
*pktout
;
4440 crState(do_ssh2_transport_state
);
4442 crBegin(ssh
->do_ssh2_transport_crstate
);
4444 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
4445 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
4446 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
4453 * Set up the preferred key exchange. (NULL => warn below here)
4455 s
->n_preferred_kex
= 0;
4456 for (i
= 0; i
< KEX_MAX
; i
++) {
4457 switch (ssh
->cfg
.ssh_kexlist
[i
]) {
4459 s
->preferred_kex
[s
->n_preferred_kex
++] =
4460 &ssh_diffiehellman_gex
;
4463 s
->preferred_kex
[s
->n_preferred_kex
++] =
4464 &ssh_diffiehellman_group14
;
4467 s
->preferred_kex
[s
->n_preferred_kex
++] =
4468 &ssh_diffiehellman_group1
;
4471 /* Flag for later. Don't bother if it's the last in
4473 if (i
< KEX_MAX
- 1) {
4474 s
->preferred_kex
[s
->n_preferred_kex
++] = NULL
;
4484 * Set up the preferred ciphers. (NULL => warn below here)
4486 s
->n_preferred_ciphers
= 0;
4487 for (i
= 0; i
< CIPHER_MAX
; i
++) {
4488 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
4489 case CIPHER_BLOWFISH
:
4490 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
4493 if (ssh
->cfg
.ssh2_des_cbc
) {
4494 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
4498 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
4501 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
4504 /* Flag for later. Don't bother if it's the last in
4506 if (i
< CIPHER_MAX
- 1) {
4507 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
4515 * Set up preferred compression.
4517 if (ssh
->cfg
.compression
)
4518 s
->preferred_comp
= &ssh_zlib
;
4520 s
->preferred_comp
= &ssh_comp_none
;
4523 * Be prepared to work around the buggy MAC problem.
4525 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
4526 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
4528 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
4532 int i
, j
, commalist_started
;
4535 * Enable queueing of outgoing auth- or connection-layer
4536 * packets while we are in the middle of a key exchange.
4538 ssh
->queueing
= TRUE
;
4541 * Flag that KEX is in progress.
4543 ssh
->kex_in_progress
= TRUE
;
4546 * Construct and send our key exchange packet.
4548 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEXINIT
);
4549 for (i
= 0; i
< 16; i
++)
4550 ssh2_pkt_addbyte(s
->pktout
, (unsigned char) random_byte());
4551 /* List key exchange algorithms. */
4552 ssh2_pkt_addstring_start(s
->pktout
);
4553 commalist_started
= 0;
4554 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4555 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4556 if (!k
) continue; /* warning flag */
4557 if (commalist_started
)
4558 ssh2_pkt_addstring_str(s
->pktout
, ",");
4559 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_kex
[i
]->name
);
4560 commalist_started
= 1;
4562 /* List server host key algorithms. */
4563 ssh2_pkt_addstring_start(s
->pktout
);
4564 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4565 ssh2_pkt_addstring_str(s
->pktout
, hostkey_algs
[i
]->name
);
4566 if (i
< lenof(hostkey_algs
) - 1)
4567 ssh2_pkt_addstring_str(s
->pktout
, ",");
4569 /* List client->server encryption algorithms. */
4570 ssh2_pkt_addstring_start(s
->pktout
);
4571 commalist_started
= 0;
4572 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4573 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4574 if (!c
) continue; /* warning flag */
4575 for (j
= 0; j
< c
->nciphers
; j
++) {
4576 if (commalist_started
)
4577 ssh2_pkt_addstring_str(s
->pktout
, ",");
4578 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4579 commalist_started
= 1;
4582 /* List server->client encryption algorithms. */
4583 ssh2_pkt_addstring_start(s
->pktout
);
4584 commalist_started
= 0;
4585 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4586 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4587 if (!c
) continue; /* warning flag */
4588 for (j
= 0; j
< c
->nciphers
; j
++) {
4589 if (commalist_started
)
4590 ssh2_pkt_addstring_str(s
->pktout
, ",");
4591 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4592 commalist_started
= 1;
4595 /* List client->server MAC algorithms. */
4596 ssh2_pkt_addstring_start(s
->pktout
);
4597 for (i
= 0; i
< s
->nmacs
; i
++) {
4598 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4599 if (i
< s
->nmacs
- 1)
4600 ssh2_pkt_addstring_str(s
->pktout
, ",");
4602 /* List server->client MAC algorithms. */
4603 ssh2_pkt_addstring_start(s
->pktout
);
4604 for (i
= 0; i
< s
->nmacs
; i
++) {
4605 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4606 if (i
< s
->nmacs
- 1)
4607 ssh2_pkt_addstring_str(s
->pktout
, ",");
4609 /* List client->server compression algorithms. */
4610 ssh2_pkt_addstring_start(s
->pktout
);
4611 assert(lenof(compressions
) > 1);
4612 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4613 for (i
= 0; i
< lenof(compressions
); i
++) {
4614 const struct ssh_compress
*c
= compressions
[i
];
4615 if (c
!= s
->preferred_comp
) {
4616 ssh2_pkt_addstring_str(s
->pktout
, ",");
4617 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4620 /* List server->client compression algorithms. */
4621 ssh2_pkt_addstring_start(s
->pktout
);
4622 assert(lenof(compressions
) > 1);
4623 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4624 for (i
= 0; i
< lenof(compressions
); i
++) {
4625 const struct ssh_compress
*c
= compressions
[i
];
4626 if (c
!= s
->preferred_comp
) {
4627 ssh2_pkt_addstring_str(s
->pktout
, ",");
4628 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4631 /* List client->server languages. Empty list. */
4632 ssh2_pkt_addstring_start(s
->pktout
);
4633 /* List server->client languages. Empty list. */
4634 ssh2_pkt_addstring_start(s
->pktout
);
4635 /* First KEX packet does _not_ follow, because we're not that brave. */
4636 ssh2_pkt_addbool(s
->pktout
, FALSE
);
4638 ssh2_pkt_adduint32(s
->pktout
, 0);
4641 ssh
->exhash
= ssh
->exhashbase
;
4642 sha_string(&ssh
->exhash
, s
->pktout
->data
+ 5, s
->pktout
->length
- 5);
4644 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
4648 if (pktin
->length
> 5)
4649 sha_string(&ssh
->exhash
, pktin
->data
+ 5, pktin
->length
- 5);
4652 * Now examine the other side's KEXINIT to see what we're up
4659 if (pktin
->type
!= SSH2_MSG_KEXINIT
) {
4660 bombout(("expected key exchange packet from server"));
4664 ssh
->hostkey
= NULL
;
4665 s
->cscipher_tobe
= NULL
;
4666 s
->sccipher_tobe
= NULL
;
4667 s
->csmac_tobe
= NULL
;
4668 s
->scmac_tobe
= NULL
;
4669 s
->cscomp_tobe
= NULL
;
4670 s
->sccomp_tobe
= NULL
;
4671 pktin
->savedpos
+= 16; /* skip garbage cookie */
4672 ssh_pkt_getstring(pktin
, &str
, &len
); /* key exchange algorithms */
4674 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4675 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4678 } else if (in_commasep_string(k
->name
, str
, len
)) {
4683 askalg(ssh
->frontend
, "key-exchange algorithm",
4689 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
4690 str ? str
: "(null)"));
4693 ssh_pkt_getstring(pktin
, &str
, &len
); /* host key algorithms */
4694 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4695 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
4696 ssh
->hostkey
= hostkey_algs
[i
];
4700 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server cipher */
4702 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4703 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4707 for (j
= 0; j
< c
->nciphers
; j
++) {
4708 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4709 s
->cscipher_tobe
= c
->list
[j
];
4714 if (s
->cscipher_tobe
) {
4716 askalg(ssh
->frontend
, "client-to-server cipher",
4717 s
->cscipher_tobe
->name
);
4721 if (!s
->cscipher_tobe
) {
4722 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
4723 str ? str
: "(null)"));
4727 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client cipher */
4729 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4730 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4734 for (j
= 0; j
< c
->nciphers
; j
++) {
4735 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4736 s
->sccipher_tobe
= c
->list
[j
];
4741 if (s
->sccipher_tobe
) {
4743 askalg(ssh
->frontend
, "server-to-client cipher",
4744 s
->sccipher_tobe
->name
);
4748 if (!s
->sccipher_tobe
) {
4749 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
4750 str ? str
: "(null)"));
4754 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server mac */
4755 for (i
= 0; i
< s
->nmacs
; i
++) {
4756 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4757 s
->csmac_tobe
= s
->maclist
[i
];
4761 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client mac */
4762 for (i
= 0; i
< s
->nmacs
; i
++) {
4763 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4764 s
->scmac_tobe
= s
->maclist
[i
];
4768 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server compression */
4769 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4770 const struct ssh_compress
*c
=
4771 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4772 if (in_commasep_string(c
->name
, str
, len
)) {
4777 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client compression */
4778 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4779 const struct ssh_compress
*c
=
4780 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4781 if (in_commasep_string(c
->name
, str
, len
)) {
4789 * Work out the number of bits of key we will need from the key
4790 * exchange. We start with the maximum key length of either
4796 csbits
= s
->cscipher_tobe
->keylen
;
4797 scbits
= s
->sccipher_tobe
->keylen
;
4798 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
4800 /* The keys only have 160-bit entropy, since they're based on
4801 * a SHA-1 hash. So cap the key size at 160 bits. */
4806 * If we're doing Diffie-Hellman group exchange, start by
4807 * requesting a group.
4809 if (!ssh
->kex
->pdata
) {
4810 logevent("Doing Diffie-Hellman group exchange");
4811 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
4813 * Work out how big a DH group we will need to allow that
4816 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
4817 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
4818 ssh2_pkt_adduint32(s
->pktout
, s
->pbits
);
4819 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
4822 if (pktin
->type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
4823 bombout(("expected key exchange group packet from server"));
4826 s
->p
= ssh2_pkt_getmp(pktin
);
4827 s
->g
= ssh2_pkt_getmp(pktin
);
4828 if (!s
->p
|| !s
->g
) {
4829 bombout(("unable to read mp-ints from incoming group packet"));
4832 ssh
->kex_ctx
= dh_setup_gex(s
->p
, s
->g
);
4833 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
4834 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
4836 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP
;
4837 ssh
->kex_ctx
= dh_setup_group(ssh
->kex
);
4838 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
4839 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
4840 logeventf(ssh
, "Using Diffie-Hellman with standard group \"%s\"",
4841 ssh
->kex
->groupname
);
4844 logevent("Doing Diffie-Hellman key exchange");
4846 * Now generate and send e for Diffie-Hellman.
4848 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
4849 s
->pktout
= ssh2_pkt_init(s
->kex_init_value
);
4850 ssh2_pkt_addmp(s
->pktout
, s
->e
);
4851 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
4854 if (pktin
->type
!= s
->kex_reply_value
) {
4855 bombout(("expected key exchange reply packet from server"));
4858 ssh_pkt_getstring(pktin
, &s
->hostkeydata
, &s
->hostkeylen
);
4859 s
->f
= ssh2_pkt_getmp(pktin
);
4861 bombout(("unable to parse key exchange reply packet"));
4864 ssh_pkt_getstring(pktin
, &s
->sigdata
, &s
->siglen
);
4866 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
4868 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
4869 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4870 sha_uint32(&ssh
->exhash
, s
->pbits
);
4871 sha_mpint(&ssh
->exhash
, s
->p
);
4872 sha_mpint(&ssh
->exhash
, s
->g
);
4874 sha_mpint(&ssh
->exhash
, s
->e
);
4875 sha_mpint(&ssh
->exhash
, s
->f
);
4876 sha_mpint(&ssh
->exhash
, s
->K
);
4877 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
4879 dh_cleanup(ssh
->kex_ctx
);
4880 ssh
->kex_ctx
= NULL
;
4883 debug(("Exchange hash is:\n"));
4884 dmemdump(s
->exchange_hash
, 20);
4887 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
4889 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
4890 (char *)s
->exchange_hash
, 20)) {
4891 bombout(("Server's host key did not match the signature supplied"));
4896 * Authenticate remote host: verify host key. (We've already
4897 * checked the signature of the exchange hash.)
4899 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
4900 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
4901 verify_ssh_host_key(ssh
->frontend
,
4902 ssh
->savedhost
, ssh
->savedport
, ssh
->hostkey
->keytype
,
4903 s
->keystr
, s
->fingerprint
);
4904 if (s
->first_kex
) { /* don't bother logging this in rekeys */
4905 logevent("Host key fingerprint is:");
4906 logevent(s
->fingerprint
);
4908 sfree(s
->fingerprint
);
4910 ssh
->hostkey
->freekey(s
->hkey
);
4913 * The exchange hash from the very first key exchange is also
4914 * the session id, used in session key construction and
4918 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
4919 sizeof(s
->exchange_hash
));
4922 * Send SSH2_MSG_NEWKEYS.
4924 s
->pktout
= ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
4925 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
4926 ssh
->outgoing_data_size
= 0; /* start counting from here */
4929 * We've sent client NEWKEYS, so create and initialise
4930 * client-to-server session keys.
4932 if (ssh
->cs_cipher_ctx
)
4933 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
4934 ssh
->cscipher
= s
->cscipher_tobe
;
4935 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
4937 if (ssh
->cs_mac_ctx
)
4938 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
4939 ssh
->csmac
= s
->csmac_tobe
;
4940 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
4942 if (ssh
->cs_comp_ctx
)
4943 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
4944 ssh
->cscomp
= s
->cscomp_tobe
;
4945 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
4948 * Set IVs on client-to-server keys. Here we use the exchange
4949 * hash from the _first_ key exchange.
4952 unsigned char keyspace
[40];
4953 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
4954 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
4955 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
4956 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
4957 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
4958 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
4961 logeventf(ssh
, "Initialised %.200s client->server encryption",
4962 ssh
->cscipher
->text_name
);
4963 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
4964 ssh
->csmac
->text_name
);
4965 if (ssh
->cscomp
->text_name
)
4966 logeventf(ssh
, "Initialised %s compression",
4967 ssh
->cscomp
->text_name
);
4970 * Now our end of the key exchange is complete, we can send all
4971 * our queued higher-layer packets.
4973 ssh
->queueing
= FALSE
;
4974 ssh2_pkt_queuesend(ssh
);
4977 * Expect SSH2_MSG_NEWKEYS from server.
4980 if (pktin
->type
!= SSH2_MSG_NEWKEYS
) {
4981 bombout(("expected new-keys packet from server"));
4984 ssh
->incoming_data_size
= 0; /* start counting from here */
4987 * We've seen server NEWKEYS, so create and initialise
4988 * server-to-client session keys.
4990 if (ssh
->sc_cipher_ctx
)
4991 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
4992 ssh
->sccipher
= s
->sccipher_tobe
;
4993 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
4995 if (ssh
->sc_mac_ctx
)
4996 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
4997 ssh
->scmac
= s
->scmac_tobe
;
4998 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
5000 if (ssh
->sc_comp_ctx
)
5001 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
5002 ssh
->sccomp
= s
->sccomp_tobe
;
5003 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
5006 * Set IVs on server-to-client keys. Here we use the exchange
5007 * hash from the _first_ key exchange.
5010 unsigned char keyspace
[40];
5011 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
5012 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
5013 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
5014 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
5015 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
5016 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
5018 logeventf(ssh
, "Initialised %.200s server->client encryption",
5019 ssh
->sccipher
->text_name
);
5020 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
5021 ssh
->scmac
->text_name
);
5022 if (ssh
->sccomp
->text_name
)
5023 logeventf(ssh
, "Initialised %s decompression",
5024 ssh
->sccomp
->text_name
);
5027 * Free key exchange data.
5031 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5037 * Key exchange is over. Schedule a timer for our next rekey.
5039 ssh
->kex_in_progress
= FALSE
;
5040 if (ssh
->cfg
.ssh_rekey_time
!= 0)
5041 ssh
->next_rekey
= schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5045 * If this is the first key exchange phase, we must pass the
5046 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5047 * wants to see it but because it will need time to initialise
5048 * itself before it sees an actual packet. In subsequent key
5049 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5050 * it would only confuse the layer above.
5052 if (!s
->first_kex
) {
5058 * Now we're encrypting. Begin returning 1 to the protocol main
5059 * function so that other things can run on top of the
5060 * transport. If we ever see a KEXINIT, we must go back to the
5063 * We _also_ go back to the start if we see pktin==NULL and
5064 * inlen==-1, because this is a special signal meaning
5065 * `initiate client-driven rekey', and `in' contains a message
5066 * giving the reason for the rekey.
5068 while (!((pktin
&& pktin
->type
== SSH2_MSG_KEXINIT
) ||
5069 (!pktin
&& inlen
== -1))) {
5073 logevent("Server initiated key re-exchange");
5075 logevent((char *)in
);
5077 goto begin_key_exchange
;
5083 * Add data to an SSH2 channel output buffer.
5085 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
5088 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
5092 * Attempt to send data on an SSH2 channel.
5094 static int ssh2_try_send(struct ssh_channel
*c
)
5097 struct Packet
*pktout
;
5099 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
5102 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
5103 if ((unsigned)len
> c
->v
.v2
.remwindow
)
5104 len
= c
->v
.v2
.remwindow
;
5105 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
5106 len
= c
->v
.v2
.remmaxpkt
;
5107 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
5108 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5109 dont_log_data(ssh
, pktout
, PKTLOG_OMIT
);
5110 ssh2_pkt_addstring_start(pktout
);
5111 ssh2_pkt_addstring_data(pktout
, data
, len
);
5112 end_log_omission(ssh
, pktout
);
5113 ssh2_pkt_send(ssh
, pktout
);
5114 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
5115 c
->v
.v2
.remwindow
-= len
;
5119 * After having sent as much data as we can, return the amount
5122 return bufchain_size(&c
->v
.v2
.outbuffer
);
5126 * Potentially enlarge the window on an SSH2 channel.
5128 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
5133 * Never send WINDOW_ADJUST for a channel that the remote side
5134 * already thinks it's closed; there's no point, since it won't
5135 * be sending any more data anyway.
5140 if (newwin
> c
->v
.v2
.locwindow
) {
5141 struct Packet
*pktout
;
5143 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5144 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5145 ssh2_pkt_adduint32(pktout
, newwin
- c
->v
.v2
.locwindow
);
5146 ssh2_pkt_send(ssh
, pktout
);
5147 c
->v
.v2
.locwindow
= newwin
;
5151 static void ssh2_msg_channel_window_adjust(Ssh ssh
, struct Packet
*pktin
)
5153 unsigned i
= ssh_pkt_getuint32(pktin
);
5154 struct ssh_channel
*c
;
5155 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5156 if (c
&& !c
->closes
)
5157 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
5160 static void ssh2_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
5164 unsigned i
= ssh_pkt_getuint32(pktin
);
5165 struct ssh_channel
*c
;
5166 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5168 return; /* nonexistent channel */
5169 if (pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5170 ssh_pkt_getuint32(pktin
) != SSH2_EXTENDED_DATA_STDERR
)
5171 return; /* extended but not stderr */
5172 ssh_pkt_getstring(pktin
, &data
, &length
);
5175 c
->v
.v2
.locwindow
-= length
;
5177 case CHAN_MAINSESSION
:
5179 from_backend(ssh
->frontend
, pktin
->type
==
5180 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5184 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5187 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5190 while (length
> 0) {
5191 if (c
->u
.a
.lensofar
< 4) {
5192 int l
= min(4 - c
->u
.a
.lensofar
, length
);
5193 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5197 c
->u
.a
.lensofar
+= l
;
5199 if (c
->u
.a
.lensofar
== 4) {
5201 4 + GET_32BIT(c
->u
.a
.msglen
);
5202 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
5204 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5206 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5208 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5210 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5214 c
->u
.a
.lensofar
+= l
;
5216 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5219 if (agent_query(c
->u
.a
.message
,
5222 ssh_agentf_callback
, c
))
5223 ssh_agentf_callback(c
, reply
, replylen
);
5224 sfree(c
->u
.a
.message
);
5225 c
->u
.a
.lensofar
= 0;
5232 * If we are not buffering too much data,
5233 * enlarge the window again at the remote side.
5235 if (bufsize
< OUR_V2_WINSIZE
)
5236 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5240 static void ssh2_msg_channel_eof(Ssh ssh
, struct Packet
*pktin
)
5242 unsigned i
= ssh_pkt_getuint32(pktin
);
5243 struct ssh_channel
*c
;
5245 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5247 return; /* nonexistent channel */
5249 if (c
->type
== CHAN_X11
) {
5251 * Remote EOF on an X11 channel means we should
5252 * wrap up and close the channel ourselves.
5254 x11_close(c
->u
.x11
.s
);
5256 } else if (c
->type
== CHAN_AGENT
) {
5258 } else if (c
->type
== CHAN_SOCKDATA
) {
5259 pfd_close(c
->u
.pfd
.s
);
5264 static void ssh2_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
5266 unsigned i
= ssh_pkt_getuint32(pktin
);
5267 struct ssh_channel
*c
;
5268 struct Packet
*pktout
;
5270 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5271 if (!c
|| ((int)c
->remoteid
) == -1) {
5272 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5273 c ?
"half-open" : "nonexistent", i
));
5276 /* Do pre-close processing on the channel. */
5278 case CHAN_MAINSESSION
:
5279 ssh
->mainchan
= NULL
;
5280 update_specials_menu(ssh
->frontend
);
5283 if (c
->u
.x11
.s
!= NULL
)
5284 x11_close(c
->u
.x11
.s
);
5291 if (c
->u
.pfd
.s
!= NULL
)
5292 pfd_close(c
->u
.pfd
.s
);
5296 if (c
->closes
== 0) {
5297 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5298 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5299 ssh2_pkt_send(ssh
, pktout
);
5301 del234(ssh
->channels
, c
);
5302 bufchain_clear(&c
->v
.v2
.outbuffer
);
5306 * See if that was the last channel left open.
5307 * (This is only our termination condition if we're
5308 * not running in -N mode.)
5310 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
5311 logevent("All channels closed. Disconnecting");
5314 * We used to send SSH_MSG_DISCONNECT here,
5315 * because I'd believed that _every_ conforming
5316 * SSH2 connection had to end with a disconnect
5317 * being sent by at least one side; apparently
5318 * I was wrong and it's perfectly OK to
5319 * unceremoniously slam the connection shut
5320 * when you're done, and indeed OpenSSH feels
5321 * this is more polite than sending a
5322 * DISCONNECT. So now we don't.
5324 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5325 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5326 ssh2_pkt_addstring(s
->pktout
, "All open channels closed");
5327 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
5328 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5330 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5334 static void ssh2_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
5336 unsigned i
= ssh_pkt_getuint32(pktin
);
5337 struct ssh_channel
*c
;
5338 struct Packet
*pktout
;
5340 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5342 return; /* nonexistent channel */
5343 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5344 return; /* dunno why they're confirming this */
5345 c
->remoteid
= ssh_pkt_getuint32(pktin
);
5346 c
->type
= CHAN_SOCKDATA
;
5347 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
5348 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
5350 pfd_confirm(c
->u
.pfd
.s
);
5353 * We have a pending close on this channel,
5354 * which we decided on before the server acked
5355 * the channel open. So now we know the
5356 * remoteid, we can close it again.
5358 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5359 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5360 ssh2_pkt_send(ssh
, pktout
);
5364 static void ssh2_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
5366 static const char *const reasons
[] = {
5367 "<unknown reason code>",
5368 "Administratively prohibited",
5370 "Unknown channel type",
5371 "Resource shortage",
5373 unsigned i
= ssh_pkt_getuint32(pktin
);
5374 unsigned reason_code
;
5375 char *reason_string
;
5378 struct ssh_channel
*c
;
5379 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5381 return; /* nonexistent channel */
5382 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5383 return; /* dunno why they're failing this */
5385 reason_code
= ssh_pkt_getuint32(pktin
);
5386 if (reason_code
>= lenof(reasons
))
5387 reason_code
= 0; /* ensure reasons[reason_code] in range */
5388 ssh_pkt_getstring(pktin
, &reason_string
, &reason_length
);
5389 message
= dupprintf("Forwarded connection refused by"
5390 " server: %s [%.*s]", reasons
[reason_code
],
5391 reason_length
, reason_string
);
5395 pfd_close(c
->u
.pfd
.s
);
5397 del234(ssh
->channels
, c
);
5401 static void ssh2_msg_channel_request(Ssh ssh
, struct Packet
*pktin
)
5405 int typelen
, want_reply
;
5406 int reply
= SSH2_MSG_CHANNEL_FAILURE
; /* default */
5407 struct ssh_channel
*c
;
5408 struct Packet
*pktout
;
5410 localid
= ssh_pkt_getuint32(pktin
);
5411 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5412 want_reply
= ssh2_pkt_getbool(pktin
);
5415 * First, check that the channel exists. Otherwise,
5416 * we can instantly disconnect with a rude message.
5418 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
5421 sprintf(buf
, "Received channel request for nonexistent"
5422 " channel %d", localid
);
5424 pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5425 ssh2_pkt_adduint32(pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5426 ssh2_pkt_addstring(pktout
, buf
);
5427 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5428 ssh2_pkt_send_noqueue(ssh
, pktout
);
5429 connection_fatal(ssh
->frontend
, "%s", buf
);
5430 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5435 * Having got the channel number, we now look at
5436 * the request type string to see if it's something
5439 if (c
== ssh
->mainchan
) {
5441 * We recognise "exit-status" and "exit-signal" on
5442 * the primary channel.
5444 if (typelen
== 11 &&
5445 !memcmp(type
, "exit-status", 11)) {
5447 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
5448 logeventf(ssh
, "Server sent command exit status %d",
5450 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5452 } else if (typelen
== 11 &&
5453 !memcmp(type
, "exit-signal", 11)) {
5455 int is_plausible
= TRUE
, is_int
= FALSE
;
5456 char *fmt_sig
= "", *fmt_msg
= "";
5458 int msglen
= 0, core
= FALSE
;
5459 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
5460 * provide an `int' for the signal, despite its
5461 * having been a `string' in the drafts since at
5462 * least 2001. (Fixed in session.c 1.147.) Try to
5463 * infer which we can safely parse it as. */
5465 unsigned char *p
= pktin
->body
+
5467 long len
= pktin
->length
- pktin
->savedpos
;
5468 unsigned long num
= GET_32BIT(p
); /* what is it? */
5469 /* If it's 0, it hardly matters; assume string */
5473 int maybe_int
= FALSE
, maybe_str
= FALSE
;
5474 #define CHECK_HYPOTHESIS(offset, result) \
5477 if (q >= 0 && q+4 <= len) { \
5478 q = q + 4 + GET_32BIT(p+q); \
5479 if (q >= 0 && q+4 <= len && \
5480 (q = q + 4 + GET_32BIT(p+q)) && q == len) \
5484 CHECK_HYPOTHESIS(4+1, maybe_int
);
5485 CHECK_HYPOTHESIS(4+num
+1, maybe_str
);
5486 #undef CHECK_HYPOTHESIS
5487 if (maybe_int
&& !maybe_str
)
5489 else if (!maybe_int
&& maybe_str
)
5492 /* Crikey. Either or neither. Panic. */
5493 is_plausible
= FALSE
;
5498 /* Old non-standard OpenSSH. */
5499 int signum
= ssh_pkt_getuint32(pktin
);
5500 fmt_sig
= dupprintf(" %d", signum
);
5502 /* As per the drafts. */
5505 ssh_pkt_getstring(pktin
, &sig
, &siglen
);
5506 /* Signal name isn't supposed to be blank, but
5507 * let's cope gracefully if it is. */
5509 fmt_sig
= dupprintf(" \"%.*s\"",
5513 core
= ssh2_pkt_getbool(pktin
);
5514 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
5516 fmt_msg
= dupprintf(" (\"%.*s\")", msglen
, msg
);
5518 /* ignore lang tag */
5519 } /* else don't attempt to parse */
5520 logeventf(ssh
, "Server exited on signal%s%s%s",
5521 fmt_sig
, core ?
" (core dumped)" : "",
5523 if (*fmt_sig
) sfree(fmt_sig
);
5524 if (*fmt_msg
) sfree(fmt_msg
);
5525 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5530 * This is a channel request we don't know
5531 * about, so we now either ignore the request
5532 * or respond with CHANNEL_FAILURE, depending
5535 reply
= SSH2_MSG_CHANNEL_FAILURE
;
5538 pktout
= ssh2_pkt_init(reply
);
5539 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5540 ssh2_pkt_send(ssh
, pktout
);
5544 static void ssh2_msg_global_request(Ssh ssh
, struct Packet
*pktin
)
5547 int typelen
, want_reply
;
5548 struct Packet
*pktout
;
5550 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5551 want_reply
= ssh2_pkt_getbool(pktin
);
5554 * We currently don't support any global requests
5555 * at all, so we either ignore the request or
5556 * respond with REQUEST_FAILURE, depending on
5560 pktout
= ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
5561 ssh2_pkt_send(ssh
, pktout
);
5565 static void ssh2_msg_channel_open(Ssh ssh
, struct Packet
*pktin
)
5573 struct ssh_channel
*c
;
5574 unsigned remid
, winsize
, pktsize
;
5575 struct Packet
*pktout
;
5577 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5578 c
= snew(struct ssh_channel
);
5581 remid
= ssh_pkt_getuint32(pktin
);
5582 winsize
= ssh_pkt_getuint32(pktin
);
5583 pktsize
= ssh_pkt_getuint32(pktin
);
5585 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5588 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5589 addrstr
= snewn(peeraddrlen
+1, char);
5590 memcpy(addrstr
, peeraddr
, peeraddrlen
);
5591 addrstr
[peeraddrlen
] = '\0';
5592 peerport
= ssh_pkt_getuint32(pktin
);
5594 logeventf(ssh
, "Received X11 connect request from %s:%d",
5597 if (!ssh
->X11_fwd_enabled
)
5598 error
= "X11 forwarding is not enabled";
5599 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
5600 ssh
->x11auth
, addrstr
, peerport
,
5601 &ssh
->cfg
) != NULL
) {
5602 error
= "Unable to open an X11 connection";
5604 logevent("Opening X11 forward connection succeeded");
5609 } else if (typelen
== 15 &&
5610 !memcmp(type
, "forwarded-tcpip", 15)) {
5611 struct ssh_rportfwd pf
, *realpf
;
5614 ssh_pkt_getstring(pktin
, &dummy
, &dummylen
);/* skip address */
5615 pf
.sport
= ssh_pkt_getuint32(pktin
);
5616 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5617 peerport
= ssh_pkt_getuint32(pktin
);
5618 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
5619 logeventf(ssh
, "Received remote port %d open request "
5620 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
5621 if (realpf
== NULL
) {
5622 error
= "Remote port is not recognised";
5624 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
5628 logeventf(ssh
, "Attempting to forward remote port to "
5629 "%s:%d", realpf
->dhost
, realpf
->dport
);
5631 logeventf(ssh
, "Port open failed: %s", e
);
5632 error
= "Port open failed";
5634 logevent("Forwarded port opened successfully");
5635 c
->type
= CHAN_SOCKDATA
;
5638 } else if (typelen
== 22 &&
5639 !memcmp(type
, "auth-agent@openssh.com", 3)) {
5640 if (!ssh
->agentfwd_enabled
)
5641 error
= "Agent forwarding is not enabled";
5643 c
->type
= CHAN_AGENT
; /* identify channel type */
5644 c
->u
.a
.lensofar
= 0;
5647 error
= "Unsupported channel type requested";
5650 c
->remoteid
= remid
;
5652 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
5653 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5654 ssh2_pkt_adduint32(pktout
, SSH2_OPEN_CONNECT_FAILED
);
5655 ssh2_pkt_addstring(pktout
, error
);
5656 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5657 ssh2_pkt_send(ssh
, pktout
);
5658 logeventf(ssh
, "Rejected channel open: %s", error
);
5661 c
->localid
= alloc_channel_id(ssh
);
5663 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5664 c
->v
.v2
.remwindow
= winsize
;
5665 c
->v
.v2
.remmaxpkt
= pktsize
;
5666 bufchain_init(&c
->v
.v2
.outbuffer
);
5667 add234(ssh
->channels
, c
);
5668 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
5669 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5670 ssh2_pkt_adduint32(pktout
, c
->localid
);
5671 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);
5672 ssh2_pkt_adduint32(pktout
, 0x4000UL
); /* our max pkt size */
5673 ssh2_pkt_send(ssh
, pktout
);
5678 * Handle the SSH2 userauth and connection layers.
5680 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
5681 struct Packet
*pktin
)
5683 struct do_ssh2_authconn_state
{
5685 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
5687 AUTH_KEYBOARD_INTERACTIVE
5691 AUTH_TYPE_PUBLICKEY
,
5692 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
5693 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
5695 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
5696 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
5698 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
5699 int tried_pubkey_config
, tried_agent
, tried_keyb_inter
;
5700 int kbd_inter_running
;
5702 int num_prompts
, curr_prompt
, echo
;
5707 void *publickey_blob
;
5708 int publickey_bloblen
;
5709 unsigned char request
[5], *response
, *p
;
5713 char *pkblob
, *alg
, *commentp
;
5714 int pklen
, alglen
, commentlen
;
5715 int siglen
, retlen
, len
;
5716 char *q
, *agentreq
, *ret
;
5718 int num_env
, env_left
, env_ok
;
5719 struct Packet
*pktout
;
5721 crState(do_ssh2_authconn_state
);
5723 crBegin(ssh
->do_ssh2_authconn_crstate
);
5726 * Request userauth protocol, and await a response to it.
5728 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
5729 ssh2_pkt_addstring(s
->pktout
, "ssh-userauth");
5730 ssh2_pkt_send(ssh
, s
->pktout
);
5731 crWaitUntilV(pktin
);
5732 if (pktin
->type
!= SSH2_MSG_SERVICE_ACCEPT
) {
5733 bombout(("Server refused user authentication protocol"));
5738 * We repeat this whole loop, including the username prompt,
5739 * until we manage a successful authentication. If the user
5740 * types the wrong _password_, they can be sent back to the
5741 * beginning to try another username, if this is configured on.
5742 * (If they specify a username in the config, they are never
5743 * asked, even if they do give a wrong password.)
5745 * I think this best serves the needs of
5747 * - the people who have no configuration, no keys, and just
5748 * want to try repeated (username,password) pairs until they
5749 * type both correctly
5751 * - people who have keys and configuration but occasionally
5752 * need to fall back to passwords
5754 * - people with a key held in Pageant, who might not have
5755 * logged in to a particular machine before; so they want to
5756 * type a username, and then _either_ their key will be
5757 * accepted, _or_ they will type a password. If they mistype
5758 * the username they will want to be able to get back and
5761 s
->username
[0] = '\0';
5762 s
->got_username
= FALSE
;
5767 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
5769 * We got a username last time round this loop, and
5770 * with change_username turned off we don't try to get
5773 } else if (!*ssh
->cfg
.username
) {
5774 if (ssh_get_line
&& !ssh_getline_pw_only
) {
5775 if (!ssh_get_line("login as: ",
5776 s
->username
, sizeof(s
->username
), FALSE
)) {
5778 * get_line failed to get a username.
5781 logevent("No username provided. Abandoning session.");
5782 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5786 int ret
; /* need not be saved across crReturn */
5787 c_write_str(ssh
, "login as: ");
5789 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
5791 crWaitUntilV(!pktin
);
5792 ret
= process_userpass_input(ssh
, in
, inlen
);
5796 c_write_str(ssh
, "\r\n");
5798 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
5801 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
5802 s
->username
[sizeof(s
->username
)-1] = '\0';
5803 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
5804 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
5805 c_write_str(ssh
, stuff
);
5809 s
->got_username
= TRUE
;
5812 * Send an authentication request using method "none": (a)
5813 * just in case it succeeds, and (b) so that we know what
5814 * authentication methods we can usefully try next.
5816 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5818 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
5819 ssh2_pkt_addstring(s
->pktout
, s
->username
);
5820 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");/* service requested */
5821 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
5822 ssh2_pkt_send(ssh
, s
->pktout
);
5823 s
->type
= AUTH_TYPE_NONE
;
5825 s
->we_are_in
= FALSE
;
5827 s
->tried_pubkey_config
= FALSE
;
5828 s
->tried_agent
= FALSE
;
5829 s
->tried_keyb_inter
= FALSE
;
5830 s
->kbd_inter_running
= FALSE
;
5831 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
5832 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
5834 logeventf(ssh
, "Reading private key file \"%.150s\"",
5835 filename_to_str(&ssh
->cfg
.keyfile
));
5836 keytype
= key_type(&ssh
->cfg
.keyfile
);
5837 if (keytype
== SSH_KEYTYPE_SSH2
) {
5839 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
5840 &s
->publickey_bloblen
, NULL
);
5843 logeventf(ssh
, "Unable to use this key file (%s)",
5844 key_type_to_str(keytype
));
5845 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
5847 filename_to_str(&ssh
->cfg
.keyfile
),
5848 key_type_to_str(keytype
));
5849 c_write_str(ssh
, msgbuf
);
5851 s
->publickey_blob
= NULL
;
5854 s
->publickey_blob
= NULL
;
5858 * Wait for the result of the last authentication request.
5861 crWaitUntilV(pktin
);
5862 while (pktin
->type
== SSH2_MSG_USERAUTH_BANNER
) {
5866 * Don't show the banner if we're operating in
5867 * non-verbose non-interactive mode. (It's probably
5868 * a script, which means nobody will read the
5869 * banner _anyway_, and moreover the printing of
5870 * the banner will screw up processing on the
5871 * output of (say) plink.)
5873 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
5874 ssh_pkt_getstring(pktin
, &banner
, &size
);
5876 c_write_untrusted(ssh
, banner
, size
);
5878 crWaitUntilV(pktin
);
5880 if (pktin
->type
== SSH2_MSG_USERAUTH_SUCCESS
) {
5881 logevent("Access granted");
5882 s
->we_are_in
= TRUE
;
5886 if (s
->kbd_inter_running
&&
5887 pktin
->type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
5889 * This is either a further set-of-prompts packet
5890 * in keyboard-interactive authentication, or it's
5891 * the same one and we came back here with `gotit'
5892 * set. In the former case, we must reset the
5893 * curr_prompt variable.
5897 } else if (pktin
->type
!= SSH2_MSG_USERAUTH_FAILURE
) {
5898 bombout(("Strange packet received during authentication: type %d",
5906 * OK, we're now sitting on a USERAUTH_FAILURE message, so
5907 * we can look at the string in it and know what we can
5908 * helpfully try next.
5910 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
) {
5913 ssh_pkt_getstring(pktin
, &methods
, &methlen
);
5914 s
->kbd_inter_running
= FALSE
;
5915 if (!ssh2_pkt_getbool(pktin
)) {
5917 * We have received an unequivocal Access
5918 * Denied. This can translate to a variety of
5921 * - if we'd just tried "none" authentication,
5922 * it's not worth printing anything at all
5924 * - if we'd just tried a public key _offer_,
5925 * the message should be "Server refused our
5926 * key" (or no message at all if the key
5927 * came from Pageant)
5929 * - if we'd just tried anything else, the
5930 * message really should be "Access denied".
5932 * Additionally, if we'd just tried password
5933 * authentication, we should break out of this
5934 * whole loop so as to go back to the username
5935 * prompt (iff we're configured to allow
5936 * username change attempts).
5938 if (s
->type
== AUTH_TYPE_NONE
) {
5940 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
5941 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
5942 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
5943 c_write_str(ssh
, "Server refused our key\r\n");
5944 logevent("Server refused public key");
5945 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
5946 /* server declined keyboard-interactive; ignore */
5948 c_write_str(ssh
, "Access denied\r\n");
5949 logevent("Access denied");
5950 if (s
->type
== AUTH_TYPE_PASSWORD
&&
5951 ssh
->cfg
.change_username
) {
5952 /* XXX perhaps we should allow
5953 * keyboard-interactive to do this too? */
5954 s
->we_are_in
= FALSE
;
5959 c_write_str(ssh
, "Further authentication required\r\n");
5960 logevent("Further authentication required");
5964 in_commasep_string("publickey", methods
, methlen
);
5966 in_commasep_string("password", methods
, methlen
);
5967 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
5968 in_commasep_string("keyboard-interactive", methods
, methlen
);
5972 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5976 * Most password/passphrase prompts will be
5977 * non-echoing, so we set this to 0 by default.
5978 * Exception is that some keyboard-interactive prompts
5979 * can be echoing, in which case we'll set this to 1.
5983 if (!s
->method
&& s
->can_pubkey
&&
5984 agent_exists() && !s
->tried_agent
) {
5986 * Attempt public-key authentication using Pageant.
5991 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5992 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
5994 s
->tried_agent
= TRUE
;
5996 logevent("Pageant is running. Requesting keys.");
5998 /* Request the keys held by the agent. */
5999 PUT_32BIT(s
->request
, 1);
6000 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
6001 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
6002 ssh_agent_callback
, ssh
)) {
6006 bombout(("Unexpected data from server while"
6007 " waiting for agent response"));
6010 } while (pktin
|| inlen
> 0);
6011 r
= ssh
->agent_response
;
6012 s
->responselen
= ssh
->agent_response_len
;
6014 s
->response
= (unsigned char *) r
;
6015 if (s
->response
&& s
->responselen
>= 5 &&
6016 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
6017 s
->p
= s
->response
+ 5;
6018 s
->nkeys
= GET_32BIT(s
->p
);
6022 sprintf(buf
, "Pageant has %d SSH2 keys", s
->nkeys
);
6025 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
6030 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
6033 s
->pklen
= GET_32BIT(s
->p
);
6035 if (s
->publickey_blob
&&
6036 s
->pklen
== s
->publickey_bloblen
&&
6037 !memcmp(s
->p
, s
->publickey_blob
,
6038 s
->publickey_bloblen
)) {
6039 logevent("This key matches configured key file");
6040 s
->tried_pubkey_config
= 1;
6042 s
->pkblob
= (char *)s
->p
;
6044 s
->alglen
= GET_32BIT(s
->pkblob
);
6045 s
->alg
= s
->pkblob
+ 4;
6046 s
->commentlen
= GET_32BIT(s
->p
);
6048 s
->commentp
= (char *)s
->p
;
6049 s
->p
+= s
->commentlen
;
6050 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6051 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6052 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6053 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6054 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6055 ssh2_pkt_addstring_start(s
->pktout
);
6056 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6057 ssh2_pkt_addstring_start(s
->pktout
);
6058 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6059 ssh2_pkt_send(ssh
, s
->pktout
);
6061 crWaitUntilV(pktin
);
6062 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6063 logevent("Key refused");
6067 if (flags
& FLAG_VERBOSE
) {
6068 c_write_str(ssh
, "Authenticating with "
6070 c_write(ssh
, s
->commentp
, s
->commentlen
);
6071 c_write_str(ssh
, "\" from agent\r\n");
6075 * Server is willing to accept the key.
6076 * Construct a SIGN_REQUEST.
6078 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6079 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6080 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6081 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6082 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6083 ssh2_pkt_addstring_start(s
->pktout
);
6084 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6085 ssh2_pkt_addstring_start(s
->pktout
);
6086 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6088 s
->siglen
= s
->pktout
->length
- 5 + 4 + 20;
6089 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6091 s
->len
= 1; /* message type */
6092 s
->len
+= 4 + s
->pklen
; /* key blob */
6093 s
->len
+= 4 + s
->siglen
; /* data to sign */
6094 s
->len
+= 4; /* flags */
6095 s
->agentreq
= snewn(4 + s
->len
, char);
6096 PUT_32BIT(s
->agentreq
, s
->len
);
6097 s
->q
= s
->agentreq
+ 4;
6098 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
6099 PUT_32BIT(s
->q
, s
->pklen
);
6101 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
6103 PUT_32BIT(s
->q
, s
->siglen
);
6105 /* Now the data to be signed... */
6106 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6107 PUT_32BIT(s
->q
, 20);
6110 memcpy(s
->q
, ssh
->v2_session_id
, 20);
6112 memcpy(s
->q
, s
->pktout
->data
+ 5,
6113 s
->pktout
->length
- 5);
6114 s
->q
+= s
->pktout
->length
- 5;
6115 /* And finally the (zero) flags word. */
6117 if (!agent_query(s
->agentreq
, s
->len
+ 4,
6119 ssh_agent_callback
, ssh
)) {
6123 bombout(("Unexpected data from server"
6124 " while waiting for agent"
6128 } while (pktin
|| inlen
> 0);
6129 vret
= ssh
->agent_response
;
6130 s
->retlen
= ssh
->agent_response_len
;
6135 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
6136 logevent("Sending Pageant's response");
6137 ssh2_add_sigblob(ssh
, s
->pktout
,
6138 s
->pkblob
, s
->pklen
,
6140 GET_32BIT(s
->ret
+ 5));
6141 ssh2_pkt_send(ssh
, s
->pktout
);
6146 ("Pageant failed to answer challenge");
6157 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
6158 && !s
->tried_pubkey_config
) {
6159 unsigned char *pub_blob
;
6160 char *algorithm
, *comment
;
6163 s
->tried_pubkey_config
= TRUE
;
6165 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6166 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6169 * Try the public key supplied in the configuration.
6171 * First, offer the public blob to see if the server is
6172 * willing to accept it.
6175 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
6180 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6181 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6182 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6183 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6184 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6185 ssh2_pkt_addstring(s
->pktout
, algorithm
);
6186 ssh2_pkt_addstring_start(s
->pktout
);
6187 ssh2_pkt_addstring_data(s
->pktout
, (char *)pub_blob
,
6189 ssh2_pkt_send(ssh
, s
->pktout
);
6190 logevent("Offered public key");
6192 crWaitUntilV(pktin
);
6193 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6195 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
6196 continue; /* key refused; give up on it */
6199 logevent("Offer of public key accepted");
6201 * Actually attempt a serious authentication using
6204 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
6205 sprintf(s
->pwprompt
,
6206 "Passphrase for key \"%.100s\": ",
6212 if (flags
& FLAG_VERBOSE
) {
6213 c_write_str(ssh
, "Authenticating with public key \"");
6214 c_write_str(ssh
, comment
);
6215 c_write_str(ssh
, "\"\r\n");
6217 s
->method
= AUTH_PUBLICKEY_FILE
;
6221 if (!s
->method
&& s
->can_keyb_inter
&& !s
->tried_keyb_inter
) {
6222 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6223 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6224 s
->tried_keyb_inter
= TRUE
;
6226 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6227 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6229 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6230 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6231 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6232 ssh2_pkt_addstring(s
->pktout
, "keyboard-interactive"); /* method */
6233 ssh2_pkt_addstring(s
->pktout
, ""); /* lang */
6234 ssh2_pkt_addstring(s
->pktout
, "");
6235 ssh2_pkt_send(ssh
, s
->pktout
);
6237 crWaitUntilV(pktin
);
6238 if (pktin
->type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6239 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
)
6241 logevent("Keyboard-interactive authentication refused");
6242 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
6246 s
->kbd_inter_running
= TRUE
;
6250 if (s
->kbd_inter_running
) {
6251 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6252 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6253 s
->tried_keyb_inter
= TRUE
;
6255 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6256 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6258 if (s
->curr_prompt
== 0) {
6260 * We've got a fresh USERAUTH_INFO_REQUEST.
6261 * Display header data, and start going through
6264 char *name
, *inst
, *lang
;
6265 int name_len
, inst_len
, lang_len
;
6267 ssh_pkt_getstring(pktin
, &name
, &name_len
);
6268 ssh_pkt_getstring(pktin
, &inst
, &inst_len
);
6269 ssh_pkt_getstring(pktin
, &lang
, &lang_len
);
6271 c_write_untrusted(ssh
, name
, name_len
);
6272 c_write_str(ssh
, "\r\n");
6275 c_write_untrusted(ssh
, inst
, inst_len
);
6276 c_write_str(ssh
, "\r\n");
6278 s
->num_prompts
= ssh_pkt_getuint32(pktin
);
6282 * If there are prompts remaining in the packet,
6283 * display one and get a response.
6285 if (s
->curr_prompt
< s
->num_prompts
) {
6289 ssh_pkt_getstring(pktin
, &prompt
, &prompt_len
);
6290 if (prompt_len
> 0) {
6291 static const char trunc
[] = "<prompt truncated>: ";
6292 static const int prlen
= sizeof(s
->pwprompt
) -
6294 if (prompt_len
> prlen
) {
6295 memcpy(s
->pwprompt
, prompt
, prlen
);
6296 strcpy(s
->pwprompt
+ prlen
, trunc
);
6298 memcpy(s
->pwprompt
, prompt
, prompt_len
);
6299 s
->pwprompt
[prompt_len
] = '\0';
6303 "<server failed to send prompt>: ");
6305 s
->echo
= ssh2_pkt_getbool(pktin
);
6311 if (!s
->method
&& s
->can_passwd
) {
6312 s
->method
= AUTH_PASSWORD
;
6313 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6314 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
6315 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
6322 if (!ssh_get_line(s
->pwprompt
, s
->password
,
6323 sizeof(s
->password
), TRUE
)) {
6325 * get_line failed to get a password (for
6326 * example because one was supplied on the
6327 * command line which has already failed to
6330 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6331 ssh2_pkt_adduint32(s
->pktout
,SSH2_DISCONNECT_BY_APPLICATION
);
6332 ssh2_pkt_addstring(s
->pktout
, "No more passwords available"
6334 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6335 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6336 logevent("Unable to authenticate");
6337 connection_fatal(ssh
->frontend
,
6338 "Unable to authenticate");
6339 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6343 int ret
; /* need not be saved across crReturn */
6344 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
6347 setup_userpass_input(ssh
, s
->password
,
6348 sizeof(s
->password
), s
->echo
);
6350 crWaitUntilV(!pktin
);
6351 ret
= process_userpass_input(ssh
, in
, inlen
);
6355 c_write_str(ssh
, "\r\n");
6359 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
6361 * We have our passphrase. Now try the actual authentication.
6363 struct ssh2_userkey
*key
;
6364 const char *error
= NULL
;
6366 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
,
6368 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
6369 if (key
== SSH2_WRONG_PASSPHRASE
) {
6370 c_write_str(ssh
, "Wrong passphrase\r\n");
6371 s
->tried_pubkey_config
= FALSE
;
6373 c_write_str(ssh
, "Unable to load private key (");
6374 c_write_str(ssh
, error
);
6375 c_write_str(ssh
, ")\r\n");
6376 s
->tried_pubkey_config
= TRUE
;
6378 /* Send a spurious AUTH_NONE to return to the top. */
6379 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6380 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6381 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6382 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6383 ssh2_pkt_send(ssh
, s
->pktout
);
6384 s
->type
= AUTH_TYPE_NONE
;
6386 unsigned char *pkblob
, *sigblob
, *sigdata
;
6387 int pkblob_len
, sigblob_len
, sigdata_len
;
6391 * We have loaded the private key and the server
6392 * has announced that it's willing to accept it.
6393 * Hallelujah. Generate a signature and send it.
6395 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6396 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6397 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6398 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6399 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6400 ssh2_pkt_addstring(s
->pktout
, key
->alg
->name
);
6401 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
6402 ssh2_pkt_addstring_start(s
->pktout
);
6403 ssh2_pkt_addstring_data(s
->pktout
, (char *)pkblob
, pkblob_len
);
6406 * The data to be signed is:
6410 * followed by everything so far placed in the
6413 sigdata_len
= s
->pktout
->length
- 5 + 4 + 20;
6414 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6416 sigdata
= snewn(sigdata_len
, unsigned char);
6418 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6419 PUT_32BIT(sigdata
+p
, 20);
6422 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
6423 memcpy(sigdata
+p
, s
->pktout
->data
+ 5,
6424 s
->pktout
->length
- 5);
6425 p
+= s
->pktout
->length
- 5;
6426 assert(p
== sigdata_len
);
6427 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
6428 sigdata_len
, &sigblob_len
);
6429 ssh2_add_sigblob(ssh
, s
->pktout
, pkblob
, pkblob_len
,
6430 sigblob
, sigblob_len
);
6435 ssh2_pkt_send(ssh
, s
->pktout
);
6436 s
->type
= AUTH_TYPE_PUBLICKEY
;
6437 key
->alg
->freekey(key
->data
);
6439 } else if (s
->method
== AUTH_PASSWORD
) {
6441 * We send the password packet lumped tightly together with
6442 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
6443 * string long enough to make the total length of the two
6444 * packets constant. This should ensure that a passive
6445 * listener doing traffic analyis can't work out the length
6448 * For this to work, we need an assumption about the
6449 * maximum length of the password packet. I think 256 is
6450 * pretty conservative. Anyone using a password longer than
6451 * that probably doesn't have much to worry about from
6452 * people who find out how long their password is!
6454 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6455 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6456 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6457 ssh2_pkt_addstring(s
->pktout
, "password");
6458 ssh2_pkt_addbool(s
->pktout
, FALSE
);
6459 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6460 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6461 memset(s
->password
, 0, sizeof(s
->password
));
6462 end_log_omission(ssh
, s
->pktout
);
6463 ssh2_pkt_defer(ssh
, s
->pktout
);
6465 * We'll include a string that's an exact multiple of the
6466 * cipher block size. If the cipher is NULL for some
6467 * reason, we don't do this trick at all because we gain
6470 if (ssh
->cscipher
) {
6473 stringlen
= (256 - ssh
->deferred_len
);
6474 stringlen
+= ssh
->cscipher
->blksize
- 1;
6475 stringlen
-= (stringlen
% ssh
->cscipher
->blksize
);
6478 * Temporarily disable actual compression,
6479 * so we can guarantee to get this string
6480 * exactly the length we want it. The
6481 * compression-disabling routine should
6482 * return an integer indicating how many
6483 * bytes we should adjust our string length
6487 ssh
->cscomp
->disable_compression(ssh
->cs_comp_ctx
);
6489 s
->pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
6490 ssh2_pkt_addstring_start(s
->pktout
);
6491 for (i
= 0; i
< stringlen
; i
++) {
6492 char c
= (char) random_byte();
6493 ssh2_pkt_addstring_data(s
->pktout
, &c
, 1);
6495 ssh2_pkt_defer(ssh
, s
->pktout
);
6497 ssh_pkt_defersend(ssh
);
6498 logevent("Sent password");
6499 s
->type
= AUTH_TYPE_PASSWORD
;
6500 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
6501 if (s
->curr_prompt
== 0) {
6502 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
6503 ssh2_pkt_adduint32(s
->pktout
, s
->num_prompts
);
6505 if (s
->need_pw
) { /* only add pw if we just got one! */
6506 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6507 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6508 memset(s
->password
, 0, sizeof(s
->password
));
6509 end_log_omission(ssh
, s
->pktout
);
6512 if (s
->curr_prompt
>= s
->num_prompts
) {
6513 ssh2_pkt_send(ssh
, s
->pktout
);
6516 * If there are prompts remaining, we set
6517 * `gotit' so that we won't attempt to get
6518 * another packet. Then we go back round the
6519 * loop and will end up retrieving another
6520 * prompt out of the existing packet. Funky or
6525 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6527 c_write_str(ssh
, "No supported authentication methods"
6528 " left to try!\r\n");
6529 logevent("No supported authentications offered."
6531 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6532 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
6533 ssh2_pkt_addstring(s
->pktout
, "No supported authentication"
6534 " methods available");
6535 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6536 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6537 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6541 } while (!s
->we_are_in
);
6544 * Now we're authenticated for the connection protocol. The
6545 * connection protocol will automatically have started at this
6546 * point; there's no need to send SERVICE_REQUEST.
6549 ssh
->channels
= newtree234(ssh_channelcmp
);
6552 * Set up handlers for some connection protocol messages, so we
6553 * don't have to handle them repeatedly in this coroutine.
6555 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] =
6556 ssh2_msg_channel_window_adjust
;
6557 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] =
6558 ssh2_msg_global_request
;
6561 * Create the main session channel.
6563 if (!ssh
->cfg
.ssh_no_shell
) {
6564 ssh
->mainchan
= snew(struct ssh_channel
);
6565 ssh
->mainchan
->ssh
= ssh
;
6566 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
6567 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
6568 ssh2_pkt_addstring(s
->pktout
, "session");
6569 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->localid
);
6570 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6571 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
6572 ssh2_pkt_adduint32(s
->pktout
, 0x4000UL
); /* our max pkt size */
6573 ssh2_pkt_send(ssh
, s
->pktout
);
6574 crWaitUntilV(pktin
);
6575 if (pktin
->type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
6576 bombout(("Server refused to open a session"));
6578 /* FIXME: error data comes back in FAILURE packet */
6580 if (ssh_pkt_getuint32(pktin
) != ssh
->mainchan
->localid
) {
6581 bombout(("Server's channel confirmation cited wrong channel"));
6584 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(pktin
);
6585 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
6586 ssh
->mainchan
->closes
= 0;
6587 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
6588 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
6589 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
6590 add234(ssh
->channels
, ssh
->mainchan
);
6591 update_specials_menu(ssh
->frontend
);
6592 logevent("Opened channel for session");
6594 ssh
->mainchan
= NULL
;
6597 * Now we have a channel, make dispatch table entries for
6598 * general channel-based messages.
6600 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] =
6601 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] =
6602 ssh2_msg_channel_data
;
6603 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = ssh2_msg_channel_eof
;
6604 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = ssh2_msg_channel_close
;
6605 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] =
6606 ssh2_msg_channel_open_confirmation
;
6607 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] =
6608 ssh2_msg_channel_open_failure
;
6609 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] =
6610 ssh2_msg_channel_request
;
6611 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] =
6612 ssh2_msg_channel_open
;
6615 * Potentially enable X11 forwarding.
6617 if (ssh
->mainchan
&& ssh
->cfg
.x11_forward
) {
6618 char proto
[20], data
[64];
6619 logevent("Requesting X11 forwarding");
6620 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
6621 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
6622 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
6623 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6624 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6625 ssh2_pkt_addstring(s
->pktout
, "x11-req");
6626 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6627 ssh2_pkt_addbool(s
->pktout
, 0); /* many connections */
6628 ssh2_pkt_addstring(s
->pktout
, proto
);
6629 ssh2_pkt_addstring(s
->pktout
, data
);
6630 ssh2_pkt_adduint32(s
->pktout
, x11_get_screen_number(ssh
->cfg
.x11_display
));
6631 ssh2_pkt_send(ssh
, s
->pktout
);
6633 crWaitUntilV(pktin
);
6635 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6636 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6637 bombout(("Unexpected response to X11 forwarding request:"
6638 " packet type %d", pktin
->type
));
6641 logevent("X11 forwarding refused");
6643 logevent("X11 forwarding enabled");
6644 ssh
->X11_fwd_enabled
= TRUE
;
6649 * Enable port forwardings.
6651 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
6654 * Potentially enable agent forwarding.
6656 if (ssh
->mainchan
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
6657 logevent("Requesting OpenSSH-style agent forwarding");
6658 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6659 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6660 ssh2_pkt_addstring(s
->pktout
, "auth-agent-req@openssh.com");
6661 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6662 ssh2_pkt_send(ssh
, s
->pktout
);
6664 crWaitUntilV(pktin
);
6666 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6667 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6668 bombout(("Unexpected response to agent forwarding request:"
6669 " packet type %d", pktin
->type
));
6672 logevent("Agent forwarding refused");
6674 logevent("Agent forwarding enabled");
6675 ssh
->agentfwd_enabled
= TRUE
;
6680 * Now allocate a pty for the session.
6682 if (ssh
->mainchan
&& !ssh
->cfg
.nopty
) {
6683 /* Unpick the terminal-speed string. */
6684 /* XXX perhaps we should allow no speeds to be sent. */
6685 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
6686 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
6687 /* Build the pty request. */
6688 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6689 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
6690 ssh2_pkt_addstring(s
->pktout
, "pty-req");
6691 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6692 ssh2_pkt_addstring(s
->pktout
, ssh
->cfg
.termtype
);
6693 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_width
);
6694 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_height
);
6695 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel width */
6696 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel height */
6697 ssh2_pkt_addstring_start(s
->pktout
);
6698 ssh2_pkt_addbyte(s
->pktout
, 128); /* TTY_OP_ISPEED */
6699 ssh2_pkt_adduint32(s
->pktout
, ssh
->ispeed
);
6700 ssh2_pkt_addbyte(s
->pktout
, 129); /* TTY_OP_OSPEED */
6701 ssh2_pkt_adduint32(s
->pktout
, ssh
->ospeed
);
6702 ssh2_pkt_addstring_data(s
->pktout
, "\0", 1); /* TTY_OP_END */
6703 ssh2_pkt_send(ssh
, s
->pktout
);
6704 ssh
->state
= SSH_STATE_INTERMED
;
6706 crWaitUntilV(pktin
);
6708 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6709 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6710 bombout(("Unexpected response to pty request:"
6711 " packet type %d", pktin
->type
));
6714 c_write_str(ssh
, "Server refused to allocate pty\r\n");
6715 ssh
->editing
= ssh
->echoing
= 1;
6717 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
6718 ssh
->ospeed
, ssh
->ispeed
);
6721 ssh
->editing
= ssh
->echoing
= 1;
6725 * Send environment variables.
6727 * Simplest thing here is to send all the requests at once, and
6728 * then wait for a whole bunch of successes or failures.
6730 if (ssh
->mainchan
&& *ssh
->cfg
.environmt
) {
6731 char *e
= ssh
->cfg
.environmt
;
6732 char *var
, *varend
, *val
;
6738 while (*e
&& *e
!= '\t') e
++;
6740 if (*e
== '\t') e
++;
6745 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6746 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6747 ssh2_pkt_addstring(s
->pktout
, "env");
6748 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6749 ssh2_pkt_addstring_start(s
->pktout
);
6750 ssh2_pkt_addstring_data(s
->pktout
, var
, varend
-var
);
6751 ssh2_pkt_addstring(s
->pktout
, val
);
6752 ssh2_pkt_send(ssh
, s
->pktout
);
6757 logeventf(ssh
, "Sent %d environment variables", s
->num_env
);
6760 s
->env_left
= s
->num_env
;
6762 while (s
->env_left
> 0) {
6763 crWaitUntilV(pktin
);
6765 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6766 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6767 bombout(("Unexpected response to environment request:"
6768 " packet type %d", pktin
->type
));
6778 if (s
->env_ok
== s
->num_env
) {
6779 logevent("All environment variables successfully set");
6780 } else if (s
->env_ok
== 0) {
6781 logevent("All environment variables refused");
6782 c_write_str(ssh
, "Server refused to set environment variables\r\n");
6784 logeventf(ssh
, "%d environment variables refused",
6785 s
->num_env
- s
->env_ok
);
6786 c_write_str(ssh
, "Server refused to set all environment variables\r\n");
6791 * Start a shell or a remote command. We may have to attempt
6792 * this twice if the config data has provided a second choice
6795 if (ssh
->mainchan
) while (1) {
6799 if (ssh
->fallback_cmd
) {
6800 subsys
= ssh
->cfg
.ssh_subsys2
;
6801 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
6803 subsys
= ssh
->cfg
.ssh_subsys
;
6804 cmd
= ssh
->cfg
.remote_cmd_ptr
;
6807 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6808 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
6810 ssh2_pkt_addstring(s
->pktout
, "subsystem");
6811 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6812 ssh2_pkt_addstring(s
->pktout
, cmd
);
6814 ssh2_pkt_addstring(s
->pktout
, "exec");
6815 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6816 ssh2_pkt_addstring(s
->pktout
, cmd
);
6818 ssh2_pkt_addstring(s
->pktout
, "shell");
6819 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6821 ssh2_pkt_send(ssh
, s
->pktout
);
6823 crWaitUntilV(pktin
);
6825 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6826 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6827 bombout(("Unexpected response to shell/command request:"
6828 " packet type %d", pktin
->type
));
6832 * We failed to start the command. If this is the
6833 * fallback command, we really are finished; if it's
6834 * not, and if the fallback command exists, try falling
6835 * back to it before complaining.
6837 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
6838 logevent("Primary command failed; attempting fallback");
6839 ssh
->fallback_cmd
= TRUE
;
6842 bombout(("Server refused to start a shell/command"));
6845 logevent("Started a shell/command");
6850 ssh
->state
= SSH_STATE_SESSION
;
6851 if (ssh
->size_needed
)
6852 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
6853 if (ssh
->eof_needed
)
6854 ssh_special(ssh
, TS_EOF
);
6860 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
6865 s
->try_send
= FALSE
;
6869 * _All_ the connection-layer packets we expect to
6870 * receive are now handled by the dispatch table.
6871 * Anything that reaches here must be bogus.
6874 bombout(("Strange packet received: type %d", pktin
->type
));
6876 } else if (ssh
->mainchan
) {
6878 * We have spare data. Add it to the channel buffer.
6880 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
6885 struct ssh_channel
*c
;
6887 * Try to send data on all channels if we can.
6889 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
6892 continue; /* don't send on closing channels */
6893 bufsize
= ssh2_try_send(c
);
6896 case CHAN_MAINSESSION
:
6897 /* stdin need not receive an unthrottle
6898 * notification since it will be polled */
6901 x11_unthrottle(c
->u
.x11
.s
);
6904 /* agent sockets are request/response and need no
6905 * buffer management */
6908 pfd_unthrottle(c
->u
.pfd
.s
);
6920 * Handlers for SSH2 messages that might arrive at any moment.
6922 void ssh2_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
6924 /* log reason code in disconnect message */
6926 int nowlen
, reason
, msglen
;
6928 reason
= ssh_pkt_getuint32(pktin
);
6929 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
6931 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
6932 buf
= dupprintf("Received disconnect message (%s)",
6933 ssh2_disconnect_reasons
[reason
]);
6935 buf
= dupprintf("Received disconnect message (unknown"
6936 " type %d)", reason
);
6940 buf
= dupprintf("Disconnection message text: %n%.*s",
6941 &nowlen
, msglen
, msg
);
6943 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
6945 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
6946 ssh2_disconnect_reasons
[reason
] : "unknown",
6951 void ssh2_msg_debug(Ssh ssh
, struct Packet
*pktin
)
6953 /* log the debug message */
6958 /* XXX maybe we should actually take notice of this */
6959 always_display
= ssh2_pkt_getbool(pktin
);
6960 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
6962 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
6967 void ssh2_msg_something_unimplemented(Ssh ssh
, struct Packet
*pktin
)
6969 struct Packet
*pktout
;
6970 pktout
= ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
6971 ssh2_pkt_adduint32(pktout
, pktin
->sequence
);
6973 * UNIMPLEMENTED messages MUST appear in the same order as the
6974 * messages they respond to. Hence, never queue them.
6976 ssh2_pkt_send_noqueue(ssh
, pktout
);
6980 * Handle the top-level SSH2 protocol.
6982 static void ssh2_protocol_setup(Ssh ssh
)
6987 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
6989 for (i
= 0; i
< 256; i
++)
6990 ssh
->packet_dispatch
[i
] = ssh2_msg_something_unimplemented
;
6993 * Any message we actually understand, we set to NULL so that
6994 * the coroutines will get it.
6996 ssh
->packet_dispatch
[SSH2_MSG_UNIMPLEMENTED
] = NULL
;
6997 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_REQUEST
] = NULL
;
6998 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_ACCEPT
] = NULL
;
6999 ssh
->packet_dispatch
[SSH2_MSG_KEXINIT
] = NULL
;
7000 ssh
->packet_dispatch
[SSH2_MSG_NEWKEYS
] = NULL
;
7001 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_INIT
] = NULL
;
7002 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_REPLY
] = NULL
;
7003 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7004 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7005 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_INIT
] = NULL
;
7006 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_REPLY
] = NULL
;
7007 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_REQUEST
] = NULL
;
7008 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_FAILURE
] = NULL
;
7009 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_SUCCESS
] = NULL
;
7010 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
7011 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_PK_OK
] = NULL
;
7012 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7013 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7014 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_INFO_RESPONSE
] = NULL
;
7015 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] = NULL
;
7016 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_SUCCESS
] = NULL
;
7017 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_FAILURE
] = NULL
;
7018 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] = NULL
;
7019 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] = NULL
;
7020 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] = NULL
;
7021 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] = NULL
;
7022 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] = NULL
;
7023 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] = NULL
;
7024 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = NULL
;
7025 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = NULL
;
7026 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] = NULL
;
7027 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_SUCCESS
] = NULL
;
7028 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_FAILURE
] = NULL
;
7031 * These special message types we install handlers for.
7033 ssh
->packet_dispatch
[SSH2_MSG_DISCONNECT
] = ssh2_msg_disconnect
;
7034 ssh
->packet_dispatch
[SSH2_MSG_IGNORE
] = ssh_msg_ignore
; /* shared with ssh1 */
7035 ssh
->packet_dispatch
[SSH2_MSG_DEBUG
] = ssh2_msg_debug
;
7038 static void ssh2_timer(void *ctx
, long now
)
7042 if (!ssh
->kex_in_progress
&&
7043 now
- ssh
->next_rekey
>= 0) {
7044 do_ssh2_transport(ssh
, "Initiating key re-exchange (timeout)",
7049 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
7050 struct Packet
*pktin
)
7052 if (ssh
->state
== SSH_STATE_CLOSED
)
7056 ssh
->incoming_data_size
+= pktin
->encrypted_len
;
7057 if (!ssh
->kex_in_progress
&&
7058 ssh
->max_data_size
!= 0 &&
7059 ssh
->incoming_data_size
> ssh
->max_data_size
)
7060 do_ssh2_transport(ssh
, "Initiating key re-exchange "
7061 "(too much data received)", -1, NULL
);
7064 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
7065 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
7069 if (!ssh
->protocol_initial_phase_done
||
7070 (pktin
&& pktin
->type
>= 20 && pktin
->type
< 50)) {
7071 if (do_ssh2_transport(ssh
, in
, inlen
, pktin
) &&
7072 !ssh
->protocol_initial_phase_done
) {
7073 ssh
->protocol_initial_phase_done
= TRUE
;
7075 * Allow authconn to initialise itself.
7077 do_ssh2_authconn(ssh
, NULL
, 0, NULL
);
7080 do_ssh2_authconn(ssh
, in
, inlen
, pktin
);
7085 * Called to set up the connection.
7087 * Returns an error message, or NULL on success.
7089 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
7091 char *host
, int port
, char **realhost
, int nodelay
,
7097 ssh
= snew(struct ssh_tag
);
7098 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7099 ssh
->version
= 0; /* when not ready yet */
7102 ssh
->v1_cipher_ctx
= NULL
;
7103 ssh
->crcda_ctx
= NULL
;
7104 ssh
->cscipher
= NULL
;
7105 ssh
->cs_cipher_ctx
= NULL
;
7106 ssh
->sccipher
= NULL
;
7107 ssh
->sc_cipher_ctx
= NULL
;
7109 ssh
->cs_mac_ctx
= NULL
;
7111 ssh
->sc_mac_ctx
= NULL
;
7113 ssh
->cs_comp_ctx
= NULL
;
7115 ssh
->sc_comp_ctx
= NULL
;
7117 ssh
->kex_ctx
= NULL
;
7118 ssh
->hostkey
= NULL
;
7120 ssh
->state
= SSH_STATE_PREPACKET
;
7121 ssh
->size_needed
= FALSE
;
7122 ssh
->eof_needed
= FALSE
;
7125 ssh
->deferred_send_data
= NULL
;
7126 ssh
->deferred_len
= 0;
7127 ssh
->deferred_size
= 0;
7128 ssh
->fallback_cmd
= 0;
7130 ssh
->x11auth
= NULL
;
7131 ssh
->v1_compressing
= FALSE
;
7132 ssh
->v2_outgoing_sequence
= 0;
7133 ssh
->ssh1_rdpkt_crstate
= 0;
7134 ssh
->ssh2_rdpkt_crstate
= 0;
7135 ssh
->do_ssh_init_crstate
= 0;
7136 ssh
->ssh_gotdata_crstate
= 0;
7137 ssh
->do_ssh1_connection_crstate
= 0;
7138 ssh
->do_ssh1_login_crstate
= 0;
7139 ssh
->do_ssh2_transport_crstate
= 0;
7140 ssh
->do_ssh2_authconn_crstate
= 0;
7141 ssh
->do_ssh_init_state
= NULL
;
7142 ssh
->do_ssh1_login_state
= NULL
;
7143 ssh
->do_ssh2_transport_state
= NULL
;
7144 ssh
->do_ssh2_authconn_state
= NULL
;
7145 ssh
->mainchan
= NULL
;
7146 ssh
->throttled_all
= 0;
7147 ssh
->v1_stdout_throttling
= 0;
7149 ssh
->queuelen
= ssh
->queuesize
= 0;
7150 ssh
->queueing
= FALSE
;
7151 ssh
->qhead
= ssh
->qtail
= NULL
;
7153 *backend_handle
= ssh
;
7156 if (crypto_startup() == 0)
7157 return "Microsoft high encryption pack not installed!";
7160 ssh
->frontend
= frontend_handle
;
7161 ssh
->term_width
= ssh
->cfg
.width
;
7162 ssh
->term_height
= ssh
->cfg
.height
;
7164 ssh
->channels
= NULL
;
7165 ssh
->rportfwds
= NULL
;
7170 ssh
->v1_throttle_count
= 0;
7171 ssh
->overall_bufsize
= 0;
7172 ssh
->fallback_cmd
= 0;
7174 ssh
->protocol
= NULL
;
7176 ssh
->protocol_initial_phase_done
= FALSE
;
7180 ssh
->incoming_data_size
= ssh
->outgoing_data_size
=
7181 ssh
->deferred_data_size
= 0L;
7182 ssh
->max_data_size
= parse_blocksize(ssh
->cfg
.ssh_rekey_data
);
7183 ssh
->kex_in_progress
= FALSE
;
7185 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
7194 static void ssh_free(void *handle
)
7196 Ssh ssh
= (Ssh
) handle
;
7197 struct ssh_channel
*c
;
7198 struct ssh_rportfwd
*pf
;
7200 if (ssh
->v1_cipher_ctx
)
7201 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
7202 if (ssh
->cs_cipher_ctx
)
7203 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
7204 if (ssh
->sc_cipher_ctx
)
7205 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
7206 if (ssh
->cs_mac_ctx
)
7207 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
7208 if (ssh
->sc_mac_ctx
)
7209 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
7210 if (ssh
->cs_comp_ctx
) {
7212 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
7214 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
7216 if (ssh
->sc_comp_ctx
) {
7218 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
7220 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
7223 dh_cleanup(ssh
->kex_ctx
);
7224 sfree(ssh
->savedhost
);
7226 while (ssh
->queuelen
-- > 0)
7227 ssh_free_packet(ssh
->queue
[ssh
->queuelen
]);
7230 while (ssh
->qhead
) {
7231 struct queued_handler
*qh
= ssh
->qhead
;
7232 ssh
->qhead
= qh
->next
;
7235 ssh
->qhead
= ssh
->qtail
= NULL
;
7237 if (ssh
->channels
) {
7238 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
7241 if (c
->u
.x11
.s
!= NULL
)
7242 x11_close(c
->u
.x11
.s
);
7245 if (c
->u
.pfd
.s
!= NULL
)
7246 pfd_close(c
->u
.pfd
.s
);
7251 freetree234(ssh
->channels
);
7252 ssh
->channels
= NULL
;
7255 if (ssh
->rportfwds
) {
7256 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
7258 freetree234(ssh
->rportfwds
);
7259 ssh
->rportfwds
= NULL
;
7261 sfree(ssh
->deferred_send_data
);
7263 x11_free_auth(ssh
->x11auth
);
7264 sfree(ssh
->do_ssh_init_state
);
7265 sfree(ssh
->do_ssh1_login_state
);
7266 sfree(ssh
->do_ssh2_transport_state
);
7267 sfree(ssh
->do_ssh2_authconn_state
);
7268 if (ssh
->crcda_ctx
) {
7269 crcda_free_context(ssh
->crcda_ctx
);
7270 ssh
->crcda_ctx
= NULL
;
7274 expire_timer_context(ssh
);
7276 pinger_free(ssh
->pinger
);
7283 * Reconfigure the SSH backend.
7285 * Currently, this function does nothing very useful. In future,
7286 * however, we could do some handy things with it. For example, we
7287 * could make the port forwarding configurer active in the Change
7288 * Settings box, and this routine could close down existing
7289 * forwardings and open up new ones in response to changes.
7291 static void ssh_reconfig(void *handle
, Config
*cfg
)
7293 Ssh ssh
= (Ssh
) handle
;
7294 pinger_reconfig(ssh
->pinger
, &ssh
->cfg
, cfg
);
7295 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7299 * Called to send data down the Telnet connection.
7301 static int ssh_send(void *handle
, char *buf
, int len
)
7303 Ssh ssh
= (Ssh
) handle
;
7305 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7308 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
7310 return ssh_sendbuffer(ssh
);
7314 * Called to query the current amount of buffered stdin data.
7316 static int ssh_sendbuffer(void *handle
)
7318 Ssh ssh
= (Ssh
) handle
;
7321 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7325 * If the SSH socket itself has backed up, add the total backup
7326 * size on that to any individual buffer on the stdin channel.
7329 if (ssh
->throttled_all
)
7330 override_value
= ssh
->overall_bufsize
;
7332 if (ssh
->version
== 1) {
7333 return override_value
;
7334 } else if (ssh
->version
== 2) {
7335 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
7336 return override_value
;
7338 return (override_value
+
7339 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
7346 * Called to set the size of the window from SSH's POV.
7348 static void ssh_size(void *handle
, int width
, int height
)
7350 Ssh ssh
= (Ssh
) handle
;
7351 struct Packet
*pktout
;
7353 ssh
->term_width
= width
;
7354 ssh
->term_height
= height
;
7356 switch (ssh
->state
) {
7357 case SSH_STATE_BEFORE_SIZE
:
7358 case SSH_STATE_PREPACKET
:
7359 case SSH_STATE_CLOSED
:
7360 break; /* do nothing */
7361 case SSH_STATE_INTERMED
:
7362 ssh
->size_needed
= TRUE
; /* buffer for later */
7364 case SSH_STATE_SESSION
:
7365 if (!ssh
->cfg
.nopty
) {
7366 if (ssh
->version
== 1) {
7367 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
7368 PKT_INT
, ssh
->term_height
,
7369 PKT_INT
, ssh
->term_width
,
7370 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
7371 } else if (ssh
->mainchan
) {
7372 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7373 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7374 ssh2_pkt_addstring(pktout
, "window-change");
7375 ssh2_pkt_addbool(pktout
, 0);
7376 ssh2_pkt_adduint32(pktout
, ssh
->term_width
);
7377 ssh2_pkt_adduint32(pktout
, ssh
->term_height
);
7378 ssh2_pkt_adduint32(pktout
, 0);
7379 ssh2_pkt_adduint32(pktout
, 0);
7380 ssh2_pkt_send(ssh
, pktout
);
7388 * Return a list of the special codes that make sense in this
7391 static const struct telnet_special
*ssh_get_specials(void *handle
)
7393 static const struct telnet_special ssh1_ignore_special
[] = {
7394 {"IGNORE message", TS_NOP
}
7396 static const struct telnet_special ssh2_transport_specials
[] = {
7397 {"IGNORE message", TS_NOP
},
7398 {"Repeat key exchange", TS_REKEY
},
7400 static const struct telnet_special ssh2_session_specials
[] = {
7403 /* These are the signal names defined by draft-ietf-secsh-connect-23.
7404 * They include all the ISO C signals, but are a subset of the POSIX
7405 * required signals. */
7406 {"SIGINT (Interrupt)", TS_SIGINT
},
7407 {"SIGTERM (Terminate)", TS_SIGTERM
},
7408 {"SIGKILL (Kill)", TS_SIGKILL
},
7409 {"SIGQUIT (Quit)", TS_SIGQUIT
},
7410 {"SIGHUP (Hangup)", TS_SIGHUP
},
7411 {"More signals", TS_SUBMENU
},
7412 {"SIGABRT", TS_SIGABRT
}, {"SIGALRM", TS_SIGALRM
},
7413 {"SIGFPE", TS_SIGFPE
}, {"SIGILL", TS_SIGILL
},
7414 {"SIGPIPE", TS_SIGPIPE
}, {"SIGSEGV", TS_SIGSEGV
},
7415 {"SIGUSR1", TS_SIGUSR1
}, {"SIGUSR2", TS_SIGUSR2
},
7418 static const struct telnet_special specials_end
[] = {
7421 /* XXX review this length for any changes: */
7422 static struct telnet_special ssh_specials
[lenof(ssh2_transport_specials
) +
7423 lenof(ssh2_session_specials
) +
7424 lenof(specials_end
)];
7425 Ssh ssh
= (Ssh
) handle
;
7427 #define ADD_SPECIALS(name) \
7429 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7430 memcpy(&ssh_specials[i], name, sizeof name); \
7434 if (ssh
->version
== 1) {
7435 /* Don't bother offering IGNORE if we've decided the remote
7436 * won't cope with it, since we wouldn't bother sending it if
7438 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7439 ADD_SPECIALS(ssh1_ignore_special
);
7440 } else if (ssh
->version
== 2) {
7441 ADD_SPECIALS(ssh2_transport_specials
);
7443 ADD_SPECIALS(ssh2_session_specials
);
7444 } /* else we're not ready yet */
7447 ADD_SPECIALS(specials_end
);
7448 return ssh_specials
;
7456 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7457 * can send an EOF and collect resulting output (e.g. `plink
7460 static void ssh_special(void *handle
, Telnet_Special code
)
7462 Ssh ssh
= (Ssh
) handle
;
7463 struct Packet
*pktout
;
7465 if (code
== TS_EOF
) {
7466 if (ssh
->state
!= SSH_STATE_SESSION
) {
7468 * Buffer the EOF in case we are pre-SESSION, so we can
7469 * send it as soon as we reach SESSION.
7472 ssh
->eof_needed
= TRUE
;
7475 if (ssh
->version
== 1) {
7476 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
7477 } else if (ssh
->mainchan
) {
7478 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
7479 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7480 ssh2_pkt_send(ssh
, pktout
);
7482 logevent("Sent EOF message");
7483 } else if (code
== TS_PING
|| code
== TS_NOP
) {
7484 if (ssh
->state
== SSH_STATE_CLOSED
7485 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7486 if (ssh
->version
== 1) {
7487 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7488 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
7490 pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
7491 ssh2_pkt_addstring_start(pktout
);
7492 ssh2_pkt_send_noqueue(ssh
, pktout
);
7494 } else if (code
== TS_REKEY
) {
7495 if (!ssh
->kex_in_progress
&& ssh
->version
== 2) {
7496 do_ssh2_transport(ssh
, "Initiating key re-exchange at"
7497 " user request", -1, NULL
);
7499 } else if (code
== TS_BRK
) {
7500 if (ssh
->state
== SSH_STATE_CLOSED
7501 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7502 if (ssh
->version
== 1) {
7503 logevent("Unable to send BREAK signal in SSH1");
7504 } else if (ssh
->mainchan
) {
7505 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7506 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7507 ssh2_pkt_addstring(pktout
, "break");
7508 ssh2_pkt_addbool(pktout
, 0);
7509 ssh2_pkt_adduint32(pktout
, 0); /* default break length */
7510 ssh2_pkt_send(ssh
, pktout
);
7513 /* Is is a POSIX signal? */
7514 char *signame
= NULL
;
7515 if (code
== TS_SIGABRT
) signame
= "ABRT";
7516 if (code
== TS_SIGALRM
) signame
= "ALRM";
7517 if (code
== TS_SIGFPE
) signame
= "FPE";
7518 if (code
== TS_SIGHUP
) signame
= "HUP";
7519 if (code
== TS_SIGILL
) signame
= "ILL";
7520 if (code
== TS_SIGINT
) signame
= "INT";
7521 if (code
== TS_SIGKILL
) signame
= "KILL";
7522 if (code
== TS_SIGPIPE
) signame
= "PIPE";
7523 if (code
== TS_SIGQUIT
) signame
= "QUIT";
7524 if (code
== TS_SIGSEGV
) signame
= "SEGV";
7525 if (code
== TS_SIGTERM
) signame
= "TERM";
7526 if (code
== TS_SIGUSR1
) signame
= "USR1";
7527 if (code
== TS_SIGUSR2
) signame
= "USR2";
7528 /* The SSH-2 protocol does in principle support arbitrary named
7529 * signals, including signame@domain, but we don't support those. */
7531 /* It's a signal. */
7532 if (ssh
->version
== 2 && ssh
->mainchan
) {
7533 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7534 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7535 ssh2_pkt_addstring(pktout
, "signal");
7536 ssh2_pkt_addbool(pktout
, 0);
7537 ssh2_pkt_addstring(pktout
, signame
);
7538 ssh2_pkt_send(ssh
, pktout
);
7539 logeventf(ssh
, "Sent signal SIG%s", signame
);
7542 /* Never heard of it. Do nothing */
7547 void *new_sock_channel(void *handle
, Socket s
)
7549 Ssh ssh
= (Ssh
) handle
;
7550 struct ssh_channel
*c
;
7551 c
= snew(struct ssh_channel
);
7555 c
->remoteid
= -1; /* to be set when open confirmed */
7556 c
->localid
= alloc_channel_id(ssh
);
7558 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
7560 bufchain_init(&c
->v
.v2
.outbuffer
);
7561 add234(ssh
->channels
, c
);
7567 * This is called when stdout/stderr (the entity to which
7568 * from_backend sends data) manages to clear some backlog.
7570 static void ssh_unthrottle(void *handle
, int bufsize
)
7572 Ssh ssh
= (Ssh
) handle
;
7573 if (ssh
->version
== 1) {
7574 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
7575 ssh
->v1_stdout_throttling
= 0;
7576 ssh1_throttle(ssh
, -1);
7579 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
7580 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
7584 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
7586 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
7588 struct Packet
*pktout
;
7590 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
7592 if (ssh
->version
== 1) {
7593 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
7594 PKT_INT
, c
->localid
,
7597 //PKT_STR, <org:orgport>,
7600 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
7601 ssh2_pkt_addstring(pktout
, "direct-tcpip");
7602 ssh2_pkt_adduint32(pktout
, c
->localid
);
7603 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7604 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);/* our window size */
7605 ssh2_pkt_adduint32(pktout
, 0x4000UL
); /* our max pkt size */
7606 ssh2_pkt_addstring(pktout
, hostname
);
7607 ssh2_pkt_adduint32(pktout
, port
);
7609 * We make up values for the originator data; partly it's
7610 * too much hassle to keep track, and partly I'm not
7611 * convinced the server should be told details like that
7612 * about my local network configuration.
7614 ssh2_pkt_addstring(pktout
, "client-side-connection");
7615 ssh2_pkt_adduint32(pktout
, 0);
7616 ssh2_pkt_send(ssh
, pktout
);
7620 static Socket
ssh_socket(void *handle
)
7622 Ssh ssh
= (Ssh
) handle
;
7626 static int ssh_sendok(void *handle
)
7628 Ssh ssh
= (Ssh
) handle
;
7629 return ssh
->send_ok
;
7632 static int ssh_ldisc(void *handle
, int option
)
7634 Ssh ssh
= (Ssh
) handle
;
7635 if (option
== LD_ECHO
)
7636 return ssh
->echoing
;
7637 if (option
== LD_EDIT
)
7638 return ssh
->editing
;
7642 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
7644 Ssh ssh
= (Ssh
) handle
;
7648 static void ssh_provide_logctx(void *handle
, void *logctx
)
7650 Ssh ssh
= (Ssh
) handle
;
7651 ssh
->logctx
= logctx
;
7654 static int ssh_return_exitcode(void *handle
)
7656 Ssh ssh
= (Ssh
) handle
;
7660 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
7664 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
7665 * that fails. This variable is the means by which scp.c can reach
7666 * into the SSH code and find out which one it got.
7668 extern int ssh_fallback_cmd(void *handle
)
7670 Ssh ssh
= (Ssh
) handle
;
7671 return ssh
->fallback_cmd
;
7674 Backend ssh_backend
= {
7684 ssh_return_exitcode
,