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_DHGROUP1 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 #define BUG_SSH2_DH_GEX 64
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_DHGROUP1
);
226 translatec(SSH2_MSG_KEXDH_REPLY
, SSH2_PKTCTX_DHGROUP1
);
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_kex
*kex_algs
[] = {
364 &ssh_diffiehellman_gex
,
368 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
370 static void *nullmac_make_context(void)
374 static void nullmac_free_context(void *handle
)
377 static void nullmac_key(void *handle
, unsigned char *key
)
380 static void nullmac_generate(void *handle
, unsigned char *blk
, int len
,
384 static int nullmac_verify(void *handle
, unsigned char *blk
, int len
,
389 const static struct ssh_mac ssh_mac_none
= {
390 nullmac_make_context
, nullmac_free_context
, nullmac_key
,
391 nullmac_generate
, nullmac_verify
, "none", 0
393 const static struct ssh_mac
*macs
[] = {
394 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
396 const static struct ssh_mac
*buggymacs
[] = {
397 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
400 static void *ssh_comp_none_init(void)
404 static void ssh_comp_none_cleanup(void *handle
)
407 static int ssh_comp_none_block(void *handle
, unsigned char *block
, int len
,
408 unsigned char **outblock
, int *outlen
)
412 static int ssh_comp_none_disable(void *handle
)
416 const static struct ssh_compress ssh_comp_none
= {
418 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
419 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
420 ssh_comp_none_disable
, NULL
422 extern const struct ssh_compress ssh_zlib
;
423 const static struct ssh_compress
*compressions
[] = {
424 &ssh_zlib
, &ssh_comp_none
427 enum { /* channel types */
432 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
436 * 2-3-4 tree storing channels.
439 Ssh ssh
; /* pointer back to main context */
440 unsigned remoteid
, localid
;
443 * In SSH1, this value contains four bits:
445 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
446 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
447 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
448 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
450 * A channel is completely finished with when all four bits are set.
454 struct ssh1_data_channel
{
457 struct ssh2_data_channel
{
459 unsigned remwindow
, remmaxpkt
;
464 struct ssh_agent_channel
{
465 unsigned char *message
;
466 unsigned char msglen
[4];
467 unsigned lensofar
, totallen
;
469 struct ssh_x11_channel
{
472 struct ssh_pfd_channel
{
479 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
480 * 2 use this structure in different ways, reflecting SSH 2's
481 * altogether saner approach to port forwarding.
483 * In SSH 1, you arrange a remote forwarding by sending the server
484 * the remote port number, and the local destination host:port.
485 * When a connection comes in, the server sends you back that
486 * host:port pair, and you connect to it. This is a ready-made
487 * security hole if you're not on the ball: a malicious server
488 * could send you back _any_ host:port pair, so if you trustingly
489 * connect to the address it gives you then you've just opened the
490 * entire inside of your corporate network just by connecting
491 * through it to a dodgy SSH server. Hence, we must store a list of
492 * host:port pairs we _are_ trying to forward to, and reject a
493 * connection request from the server if it's not in the list.
495 * In SSH 2, each side of the connection minds its own business and
496 * doesn't send unnecessary information to the other. You arrange a
497 * remote forwarding by sending the server just the remote port
498 * number. When a connection comes in, the server tells you which
499 * of its ports was connected to; and _you_ have to remember what
500 * local host:port pair went with that port number.
502 * Hence: in SSH 1 this structure stores host:port pairs we intend
503 * to allow connections to, and is indexed by those host:port
504 * pairs. In SSH 2 it stores a mapping from source port to
505 * destination host:port pair, and is indexed by source port.
507 struct ssh_rportfwd
{
508 unsigned sport
, dport
;
515 unsigned long sequence
;
520 long encrypted_len
; /* for SSH2 total-size counting */
523 * State associated with packet logging
527 struct logblank_t
*blanks
;
530 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
531 struct Packet
*pktin
);
532 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
533 struct Packet
*pktin
);
534 static void ssh1_protocol_setup(Ssh ssh
);
535 static void ssh2_protocol_setup(Ssh ssh
);
536 static void ssh_size(void *handle
, int width
, int height
);
537 static void ssh_special(void *handle
, Telnet_Special
);
538 static int ssh2_try_send(struct ssh_channel
*c
);
539 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
540 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
541 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
542 static int ssh_sendbuffer(void *handle
);
543 static void ssh_do_close(Ssh ssh
);
544 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
);
545 static int ssh2_pkt_getbool(struct Packet
*pkt
);
546 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
);
547 static void ssh2_timer(void *ctx
, long now
);
548 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
,
549 struct Packet
*pktin
);
551 struct rdpkt1_state_tag
{
552 long len
, pad
, biglen
, to_read
;
553 unsigned long realcrc
, gotcrc
;
557 struct Packet
*pktin
;
560 struct rdpkt2_state_tag
{
561 long len
, pad
, payload
, packetlen
, maclen
;
564 unsigned long incoming_sequence
;
565 struct Packet
*pktin
;
568 typedef void (*handler_fn_t
)(Ssh ssh
, struct Packet
*pktin
);
571 const struct plug_function_table
*fn
;
572 /* the above field _must_ be first in the structure */
574 SHA_State exhash
, exhashbase
;
581 unsigned char session_key
[32];
583 int v1_remote_protoflags
;
584 int v1_local_protoflags
;
585 int agentfwd_enabled
;
588 const struct ssh_cipher
*cipher
;
591 const struct ssh2_cipher
*cscipher
, *sccipher
;
592 void *cs_cipher_ctx
, *sc_cipher_ctx
;
593 const struct ssh_mac
*csmac
, *scmac
;
594 void *cs_mac_ctx
, *sc_mac_ctx
;
595 const struct ssh_compress
*cscomp
, *sccomp
;
596 void *cs_comp_ctx
, *sc_comp_ctx
;
597 const struct ssh_kex
*kex
;
598 const struct ssh_signkey
*hostkey
;
599 unsigned char v2_session_id
[20];
605 int echoing
, editing
;
609 int ospeed
, ispeed
; /* temporaries */
610 int term_width
, term_height
;
612 tree234
*channels
; /* indexed by local id */
613 struct ssh_channel
*mainchan
; /* primary session channel */
620 SSH_STATE_BEFORE_SIZE
,
626 int size_needed
, eof_needed
;
628 struct Packet
**queue
;
629 int queuelen
, queuesize
;
631 unsigned char *deferred_send_data
;
632 int deferred_len
, deferred_size
;
635 * Gross hack: pscp will try to start SFTP but fall back to
636 * scp1 if that fails. This variable is the means by which
637 * scp.c can reach into the SSH code and find out which one it
643 * Used for username and password input.
645 char *userpass_input_buffer
;
646 int userpass_input_buflen
;
647 int userpass_input_bufpos
;
648 int userpass_input_echo
;
650 char *portfwd_strptr
;
656 int v1_throttle_count
;
659 int v1_stdout_throttling
;
660 int v2_outgoing_sequence
;
662 int ssh1_rdpkt_crstate
;
663 int ssh2_rdpkt_crstate
;
664 int do_ssh_init_crstate
;
665 int ssh_gotdata_crstate
;
666 int do_ssh1_login_crstate
;
667 int do_ssh1_connection_crstate
;
668 int do_ssh2_transport_crstate
;
669 int do_ssh2_authconn_crstate
;
671 void *do_ssh_init_state
;
672 void *do_ssh1_login_state
;
673 void *do_ssh2_transport_state
;
674 void *do_ssh2_authconn_state
;
676 struct rdpkt1_state_tag rdpkt1_state
;
677 struct rdpkt2_state_tag rdpkt2_state
;
679 /* ssh1 and ssh2 use this for different things, but both use it */
680 int protocol_initial_phase_done
;
682 void (*protocol
) (Ssh ssh
, unsigned char *in
, int inlen
,
684 struct Packet
*(*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
687 * We maintain a full _copy_ of a Config structure here, not
688 * merely a pointer to it. That way, when we're passed a new
689 * one for reconfiguration, we can check the differences and
690 * potentially reconfigure port forwardings etc in mid-session.
695 * Used to transfer data back from async agent callbacks.
697 void *agent_response
;
698 int agent_response_len
;
701 * Dispatch table for packet types that we may have to deal
704 handler_fn_t packet_dispatch
[256];
707 * This module deals with sending keepalives.
712 * Track incoming and outgoing data sizes and time, for
715 unsigned long incoming_data_size
, outgoing_data_size
, deferred_data_size
;
720 #define MAX_DATA_BEFORE_REKEY (0x40000000UL)
721 #define REKEY_TIMEOUT (3600 * TICKSPERSEC)
723 #define logevent(s) logevent(ssh->frontend, s)
725 /* logevent, only printf-formatted. */
726 static void logeventf(Ssh ssh
, const char *fmt
, ...)
732 buf
= dupvprintf(fmt
, ap
);
738 #define bombout(msg) \
740 char *text = dupprintf msg; \
743 connection_fatal(ssh->frontend, "%s", text); \
747 /* Functions to leave bits out of the SSH packet log file. */
749 static void dont_log_password(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
751 if (ssh
->cfg
.logomitpass
)
752 pkt
->logmode
= blanktype
;
755 static void dont_log_data(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
757 if (ssh
->cfg
.logomitdata
)
758 pkt
->logmode
= blanktype
;
761 static void end_log_omission(Ssh ssh
, struct Packet
*pkt
)
763 pkt
->logmode
= PKTLOG_EMIT
;
766 static int ssh_channelcmp(void *av
, void *bv
)
768 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
769 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
770 if (a
->localid
< b
->localid
)
772 if (a
->localid
> b
->localid
)
776 static int ssh_channelfind(void *av
, void *bv
)
778 unsigned *a
= (unsigned *) av
;
779 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
787 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
789 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
790 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
792 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
793 return i
< 0 ?
-1 : +1;
794 if (a
->dport
> b
->dport
)
796 if (a
->dport
< b
->dport
)
801 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
803 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
804 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
806 if (a
->sport
> b
->sport
)
808 if (a
->sport
< b
->sport
)
813 static int alloc_channel_id(Ssh ssh
)
815 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
816 unsigned low
, high
, mid
;
818 struct ssh_channel
*c
;
821 * First-fit allocation of channel numbers: always pick the
822 * lowest unused one. To do this, binary-search using the
823 * counted B-tree to find the largest channel ID which is in a
824 * contiguous sequence from the beginning. (Precisely
825 * everything in that sequence must have ID equal to its tree
826 * index plus CHANNEL_NUMBER_OFFSET.)
828 tsize
= count234(ssh
->channels
);
832 while (high
- low
> 1) {
833 mid
= (high
+ low
) / 2;
834 c
= index234(ssh
->channels
, mid
);
835 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
836 low
= mid
; /* this one is fine */
838 high
= mid
; /* this one is past it */
841 * Now low points to either -1, or the tree index of the
842 * largest ID in the initial sequence.
845 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
846 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
848 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
851 static void c_write(Ssh ssh
, const char *buf
, int len
)
853 if ((flags
& FLAG_STDERR
)) {
855 for (i
= 0; i
< len
; i
++)
857 fputc(buf
[i
], stderr
);
860 from_backend(ssh
->frontend
, 1, buf
, len
);
863 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
866 for (i
= 0; i
< len
; i
++) {
868 c_write(ssh
, "\r\n", 2);
869 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
870 c_write(ssh
, buf
+ i
, 1);
874 static void c_write_str(Ssh ssh
, const char *buf
)
876 c_write(ssh
, buf
, strlen(buf
));
879 static void ssh_free_packet(struct Packet
*pkt
)
884 static struct Packet
*ssh_new_packet(void)
886 struct Packet
*pkt
= snew(struct Packet
);
890 pkt
->logmode
= PKTLOG_EMIT
;
898 * Collect incoming data in the incoming packet buffer.
899 * Decipher and verify the packet when it is completely read.
900 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
901 * Update the *data and *datalen variables.
902 * Return a Packet structure when a packet is completed.
904 static struct Packet
*ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
906 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
908 crBegin(ssh
->ssh1_rdpkt_crstate
);
910 st
->pktin
= ssh_new_packet();
913 st
->pktin
->length
= 0;
915 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
916 while ((*datalen
) == 0)
918 st
->len
= (st
->len
<< 8) + **data
;
919 (*data
)++, (*datalen
)--;
922 st
->pad
= 8 - (st
->len
% 8);
923 st
->biglen
= st
->len
+ st
->pad
;
924 st
->pktin
->length
= st
->len
- 5;
926 if (st
->biglen
< 0) {
927 bombout(("Extremely large packet length from server suggests"
928 " data stream corruption"));
929 ssh_free_packet(st
->pktin
);
933 st
->pktin
->maxlen
= st
->biglen
;
934 st
->pktin
->data
= snewn(st
->biglen
+ APIEXTRA
, unsigned char);
936 st
->to_read
= st
->biglen
;
937 st
->p
= st
->pktin
->data
;
938 while (st
->to_read
> 0) {
939 st
->chunk
= st
->to_read
;
940 while ((*datalen
) == 0)
942 if (st
->chunk
> (*datalen
))
943 st
->chunk
= (*datalen
);
944 memcpy(st
->p
, *data
, st
->chunk
);
946 *datalen
-= st
->chunk
;
948 st
->to_read
-= st
->chunk
;
951 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, st
->pktin
->data
,
953 bombout(("Network attack (CRC compensation) detected!"));
954 ssh_free_packet(st
->pktin
);
959 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, st
->pktin
->data
, st
->biglen
);
961 st
->realcrc
= crc32_compute(st
->pktin
->data
, st
->biglen
- 4);
962 st
->gotcrc
= GET_32BIT(st
->pktin
->data
+ st
->biglen
- 4);
963 if (st
->gotcrc
!= st
->realcrc
) {
964 bombout(("Incorrect CRC received on packet"));
965 ssh_free_packet(st
->pktin
);
969 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
970 st
->pktin
->savedpos
= 0;
972 if (ssh
->v1_compressing
) {
973 unsigned char *decompblk
;
975 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
976 st
->pktin
->body
- 1, st
->pktin
->length
+ 1,
977 &decompblk
, &decomplen
)) {
978 bombout(("Zlib decompression encountered invalid data"));
979 ssh_free_packet(st
->pktin
);
983 if (st
->pktin
->maxlen
< st
->pad
+ decomplen
) {
984 st
->pktin
->maxlen
= st
->pad
+ decomplen
;
985 st
->pktin
->data
= sresize(st
->pktin
->data
,
986 st
->pktin
->maxlen
+ APIEXTRA
,
988 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
991 memcpy(st
->pktin
->body
- 1, decompblk
, decomplen
);
993 st
->pktin
->length
= decomplen
- 1;
996 st
->pktin
->type
= st
->pktin
->body
[-1];
999 * Log incoming packet, possibly omitting sensitive fields.
1003 struct logblank_t blank
;
1004 if (ssh
->cfg
.logomitdata
) {
1005 int do_blank
= FALSE
, blank_prefix
= 0;
1006 /* "Session data" packets - omit the data field */
1007 if ((st
->pktin
->type
== SSH1_SMSG_STDOUT_DATA
) ||
1008 (st
->pktin
->type
== SSH1_SMSG_STDERR_DATA
)) {
1009 do_blank
= TRUE
; blank_prefix
= 0;
1010 } else if (st
->pktin
->type
== SSH1_MSG_CHANNEL_DATA
) {
1011 do_blank
= TRUE
; blank_prefix
= 4;
1014 blank
.offset
= blank_prefix
;
1015 blank
.len
= st
->pktin
->length
;
1016 blank
.type
= PKTLOG_OMIT
;
1020 log_packet(ssh
->logctx
,
1021 PKT_INCOMING
, st
->pktin
->type
,
1022 ssh1_pkt_type(st
->pktin
->type
),
1023 st
->pktin
->body
, st
->pktin
->length
,
1027 crFinish(st
->pktin
);
1030 static struct Packet
*ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1032 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1034 crBegin(ssh
->ssh2_rdpkt_crstate
);
1036 st
->pktin
= ssh_new_packet();
1038 st
->pktin
->type
= 0;
1039 st
->pktin
->length
= 0;
1041 st
->cipherblk
= ssh
->sccipher
->blksize
;
1044 if (st
->cipherblk
< 8)
1047 st
->pktin
->data
= snewn(st
->cipherblk
+ APIEXTRA
, unsigned char);
1050 * Acquire and decrypt the first block of the packet. This will
1051 * contain the length and padding details.
1053 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1054 while ((*datalen
) == 0)
1056 st
->pktin
->data
[st
->i
] = *(*data
)++;
1061 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1062 st
->pktin
->data
, st
->cipherblk
);
1065 * Now get the length and padding figures.
1067 st
->len
= GET_32BIT(st
->pktin
->data
);
1068 st
->pad
= st
->pktin
->data
[4];
1071 * _Completely_ silly lengths should be stomped on before they
1072 * do us any more damage.
1074 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
1075 bombout(("Incoming packet was garbled on decryption"));
1076 ssh_free_packet(st
->pktin
);
1081 * This enables us to deduce the payload length.
1083 st
->payload
= st
->len
- st
->pad
- 1;
1085 st
->pktin
->length
= st
->payload
+ 5;
1088 * So now we can work out the total packet length.
1090 st
->packetlen
= st
->len
+ 4;
1091 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1094 * Allocate memory for the rest of the packet.
1096 st
->pktin
->maxlen
= st
->packetlen
+ st
->maclen
;
1097 st
->pktin
->data
= sresize(st
->pktin
->data
,
1098 st
->pktin
->maxlen
+ APIEXTRA
,
1102 * Read and decrypt the remainder of the packet.
1104 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1106 while ((*datalen
) == 0)
1108 st
->pktin
->data
[st
->i
] = *(*data
)++;
1111 /* Decrypt everything _except_ the MAC. */
1113 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1114 st
->pktin
->data
+ st
->cipherblk
,
1115 st
->packetlen
- st
->cipherblk
);
1117 st
->pktin
->encrypted_len
= st
->packetlen
;
1123 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, st
->pktin
->data
, st
->len
+ 4,
1124 st
->incoming_sequence
)) {
1125 bombout(("Incorrect MAC received on packet"));
1126 ssh_free_packet(st
->pktin
);
1130 st
->pktin
->sequence
= st
->incoming_sequence
++;
1133 * Decompress packet payload.
1136 unsigned char *newpayload
;
1139 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1140 st
->pktin
->data
+ 5, st
->pktin
->length
- 5,
1141 &newpayload
, &newlen
)) {
1142 if (st
->pktin
->maxlen
< newlen
+ 5) {
1143 st
->pktin
->maxlen
= newlen
+ 5;
1144 st
->pktin
->data
= sresize(st
->pktin
->data
,
1145 st
->pktin
->maxlen
+ APIEXTRA
,
1148 st
->pktin
->length
= 5 + newlen
;
1149 memcpy(st
->pktin
->data
+ 5, newpayload
, newlen
);
1154 st
->pktin
->savedpos
= 6;
1155 st
->pktin
->body
= st
->pktin
->data
;
1156 st
->pktin
->type
= st
->pktin
->data
[5];
1159 * Log incoming packet, possibly omitting sensitive fields.
1163 struct logblank_t blank
;
1164 if (ssh
->cfg
.logomitdata
) {
1165 int do_blank
= FALSE
, blank_prefix
= 0;
1166 /* "Session data" packets - omit the data field */
1167 if (st
->pktin
->type
== SSH2_MSG_CHANNEL_DATA
) {
1168 do_blank
= TRUE
; blank_prefix
= 4;
1169 } else if (st
->pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1170 do_blank
= TRUE
; blank_prefix
= 8;
1173 blank
.offset
= blank_prefix
;
1174 blank
.len
= (st
->pktin
->length
-6) - blank_prefix
;
1175 blank
.type
= PKTLOG_OMIT
;
1179 log_packet(ssh
->logctx
, PKT_INCOMING
, st
->pktin
->type
,
1180 ssh2_pkt_type(ssh
->pkt_ctx
, st
->pktin
->type
),
1181 st
->pktin
->data
+6, st
->pktin
->length
-6,
1185 crFinish(st
->pktin
);
1188 static void ssh1_pktout_size(struct Packet
*pkt
, int len
)
1192 len
+= 5; /* type and CRC */
1193 pad
= 8 - (len
% 8);
1196 pkt
->length
= len
- 5;
1197 if (pkt
->maxlen
< biglen
) {
1198 pkt
->maxlen
= biglen
;
1199 pkt
->data
= sresize(pkt
->data
, biglen
+ 4 + APIEXTRA
, unsigned char);
1201 pkt
->body
= pkt
->data
+ 4 + pad
+ 1;
1204 static struct Packet
*s_wrpkt_start(int type
, int len
)
1206 struct Packet
*pkt
= ssh_new_packet();
1207 ssh1_pktout_size(pkt
, len
);
1209 /* Initialise log omission state */
1215 static int s_wrpkt_prepare(Ssh ssh
, struct Packet
*pkt
)
1221 * XXX various versions of SC (including 8.8.4) screw up the
1222 * register allocation in this function and use the same register
1223 * (D6) for len and as a temporary, with predictable results. The
1224 * following sledgehammer prevents this.
1230 pkt
->body
[-1] = pkt
->type
;
1233 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->type
,
1234 ssh1_pkt_type(pkt
->type
),
1235 pkt
->body
, pkt
->length
,
1236 pkt
->nblanks
, pkt
->blanks
);
1237 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1240 if (ssh
->v1_compressing
) {
1241 unsigned char *compblk
;
1243 zlib_compress_block(ssh
->cs_comp_ctx
,
1244 pkt
->body
- 1, pkt
->length
+ 1,
1245 &compblk
, &complen
);
1246 ssh1_pktout_size(pkt
, complen
- 1);
1247 memcpy(pkt
->body
- 1, compblk
, complen
);
1251 len
= pkt
->length
+ 5; /* type and CRC */
1252 pad
= 8 - (len
% 8);
1255 for (i
= 0; i
< pad
; i
++)
1256 pkt
->data
[i
+ 4] = random_byte();
1257 crc
= crc32_compute(pkt
->data
+ 4, biglen
- 4);
1258 PUT_32BIT(pkt
->data
+ biglen
, crc
);
1259 PUT_32BIT(pkt
->data
, len
);
1262 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, pkt
->data
+ 4, biglen
);
1267 static void s_wrpkt(Ssh ssh
, struct Packet
*pkt
)
1270 len
= s_wrpkt_prepare(ssh
, pkt
);
1271 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1272 if (backlog
> SSH_MAX_BACKLOG
)
1273 ssh_throttle_all(ssh
, 1, backlog
);
1276 static void s_wrpkt_defer(Ssh ssh
, struct Packet
*pkt
)
1279 len
= s_wrpkt_prepare(ssh
, pkt
);
1280 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1281 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1282 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1286 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1287 ssh
->deferred_len
+= len
;
1291 * Construct a packet with the specified contents.
1293 static struct Packet
*construct_packet(Ssh ssh
, int pkttype
,
1294 va_list ap1
, va_list ap2
)
1296 unsigned char *p
, *argp
, argchar
;
1297 unsigned long argint
;
1298 int pktlen
, argtype
, arglen
;
1303 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1306 (void) va_arg(ap1
, int);
1310 (void) va_arg(ap1
, int);
1314 (void) va_arg(ap1
, unsigned char *);
1315 arglen
= va_arg(ap1
, int);
1319 argp
= va_arg(ap1
, unsigned char *);
1320 arglen
= strlen((char *)argp
);
1321 pktlen
+= 4 + arglen
;
1324 bn
= va_arg(ap1
, Bignum
);
1325 pktlen
+= ssh1_bignum_length(bn
);
1330 /* ignore this pass */
1337 pkt
= s_wrpkt_start(pkttype
, pktlen
);
1340 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1341 int offset
= p
- pkt
->body
, len
= 0;
1343 /* Actual fields in the packet */
1345 argint
= va_arg(ap2
, int);
1346 PUT_32BIT(p
, argint
);
1350 argchar
= (unsigned char) va_arg(ap2
, int);
1355 argp
= va_arg(ap2
, unsigned char *);
1356 arglen
= va_arg(ap2
, int);
1357 memcpy(p
, argp
, arglen
);
1361 argp
= va_arg(ap2
, unsigned char *);
1362 arglen
= strlen((char *)argp
);
1363 PUT_32BIT(p
, arglen
);
1364 memcpy(p
+ 4, argp
, arglen
);
1368 bn
= va_arg(ap2
, Bignum
);
1369 len
= ssh1_write_bignum(p
, bn
);
1371 /* Tokens for modifications to packet logging */
1373 dont_log_password(ssh
, pkt
, PKTLOG_BLANK
);
1376 dont_log_data(ssh
, pkt
, PKTLOG_OMIT
);
1379 end_log_omission(ssh
, pkt
);
1383 /* Deal with logfile omission, if required. */
1384 if (len
&& (pkt
->logmode
!= PKTLOG_EMIT
)) {
1386 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
,
1388 pkt
->blanks
[pkt
->nblanks
-1].offset
= offset
;
1389 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1390 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1397 static void send_packet(Ssh ssh
, int pkttype
, ...)
1401 va_start(ap1
, pkttype
);
1402 va_start(ap2
, pkttype
);
1403 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1407 ssh_free_packet(pkt
);
1410 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1414 va_start(ap1
, pkttype
);
1415 va_start(ap2
, pkttype
);
1416 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1419 s_wrpkt_defer(ssh
, pkt
);
1420 ssh_free_packet(pkt
);
1423 static int ssh_versioncmp(char *a
, char *b
)
1426 unsigned long av
, bv
;
1428 av
= strtoul(a
, &ae
, 10);
1429 bv
= strtoul(b
, &be
, 10);
1431 return (av
< bv ?
-1 : +1);
1436 av
= strtoul(ae
, &ae
, 10);
1437 bv
= strtoul(be
, &be
, 10);
1439 return (av
< bv ?
-1 : +1);
1444 * Utility routines for putting an SSH-protocol `string' and
1445 * `uint32' into a SHA state.
1448 static void sha_string(SHA_State
* s
, void *str
, int len
)
1450 unsigned char lenblk
[4];
1451 PUT_32BIT(lenblk
, len
);
1452 SHA_Bytes(s
, lenblk
, 4);
1453 SHA_Bytes(s
, str
, len
);
1456 static void sha_uint32(SHA_State
* s
, unsigned i
)
1458 unsigned char intblk
[4];
1459 PUT_32BIT(intblk
, i
);
1460 SHA_Bytes(s
, intblk
, 4);
1464 * SSH2 packet construction functions.
1466 static void ssh2_pkt_ensure(struct Packet
*pkt
, int length
)
1468 if (pkt
->maxlen
< length
) {
1469 pkt
->maxlen
= length
+ 256;
1470 pkt
->data
= sresize(pkt
->data
, pkt
->maxlen
+ APIEXTRA
, unsigned char);
1473 static void ssh2_pkt_adddata(struct Packet
*pkt
, void *data
, int len
)
1475 if (pkt
->logmode
!= PKTLOG_EMIT
) {
1477 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
, struct logblank_t
);
1478 pkt
->blanks
[pkt
->nblanks
-1].offset
= pkt
->length
- 6;
1479 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1480 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1483 ssh2_pkt_ensure(pkt
, pkt
->length
);
1484 memcpy(pkt
->data
+ pkt
->length
- len
, data
, len
);
1486 static void ssh2_pkt_addbyte(struct Packet
*pkt
, unsigned char byte
)
1488 ssh2_pkt_adddata(pkt
, &byte
, 1);
1490 static struct Packet
*ssh2_pkt_init(int pkt_type
)
1492 struct Packet
*pkt
= ssh_new_packet();
1494 ssh2_pkt_addbyte(pkt
, (unsigned char) pkt_type
);
1497 static void ssh2_pkt_addbool(struct Packet
*pkt
, unsigned char value
)
1499 ssh2_pkt_adddata(pkt
, &value
, 1);
1501 static void ssh2_pkt_adduint32(struct Packet
*pkt
, unsigned long value
)
1504 PUT_32BIT(x
, value
);
1505 ssh2_pkt_adddata(pkt
, x
, 4);
1507 static void ssh2_pkt_addstring_start(struct Packet
*pkt
)
1509 ssh2_pkt_adduint32(pkt
, 0);
1510 pkt
->savedpos
= pkt
->length
;
1512 static void ssh2_pkt_addstring_str(struct Packet
*pkt
, char *data
)
1514 ssh2_pkt_adddata(pkt
, data
, strlen(data
));
1515 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1517 static void ssh2_pkt_addstring_data(struct Packet
*pkt
, char *data
, int len
)
1519 ssh2_pkt_adddata(pkt
, data
, len
);
1520 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1522 static void ssh2_pkt_addstring(struct Packet
*pkt
, char *data
)
1524 ssh2_pkt_addstring_start(pkt
);
1525 ssh2_pkt_addstring_str(pkt
, data
);
1527 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1530 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1531 p
= snewn(n
+ 1, unsigned char);
1533 fatalbox("out of memory");
1535 for (i
= 1; i
<= n
; i
++)
1536 p
[i
] = bignum_byte(b
, n
- i
);
1538 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1540 memmove(p
, p
+ i
, n
+ 1 - i
);
1544 static void ssh2_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1548 p
= ssh2_mpint_fmt(b
, &len
);
1549 ssh2_pkt_addstring_start(pkt
);
1550 ssh2_pkt_addstring_data(pkt
, (char *)p
, len
);
1555 * Construct an SSH2 final-form packet: compress it, encrypt it,
1556 * put the MAC on it. Final packet, ready to be sent, is stored in
1557 * pkt->data. Total length is returned.
1559 static int ssh2_pkt_construct(Ssh ssh
, struct Packet
*pkt
)
1561 int cipherblk
, maclen
, padding
, i
;
1564 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[5],
1565 ssh2_pkt_type(ssh
->pkt_ctx
, pkt
->data
[5]),
1566 pkt
->data
+ 6, pkt
->length
- 6,
1567 pkt
->nblanks
, pkt
->blanks
);
1568 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1572 * Compress packet payload.
1575 unsigned char *newpayload
;
1578 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, pkt
->data
+ 5,
1580 &newpayload
, &newlen
)) {
1582 ssh2_pkt_adddata(pkt
, newpayload
, newlen
);
1588 * Add padding. At least four bytes, and must also bring total
1589 * length (minus MAC) up to a multiple of the block size.
1591 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1592 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1595 (cipherblk
- (pkt
->length
+ padding
) % cipherblk
) % cipherblk
;
1596 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1597 ssh2_pkt_ensure(pkt
, pkt
->length
+ padding
+ maclen
);
1598 pkt
->data
[4] = padding
;
1599 for (i
= 0; i
< padding
; i
++)
1600 pkt
->data
[pkt
->length
+ i
] = random_byte();
1601 PUT_32BIT(pkt
->data
, pkt
->length
+ padding
- 4);
1603 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, pkt
->data
,
1604 pkt
->length
+ padding
,
1605 ssh
->v2_outgoing_sequence
);
1606 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1609 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1610 pkt
->data
, pkt
->length
+ padding
);
1612 pkt
->encrypted_len
= pkt
->length
+ padding
;
1614 /* Ready-to-send packet starts at pkt->data. We return length. */
1615 return pkt
->length
+ padding
+ maclen
;
1619 * Routines called from the main SSH code to send packets. There
1620 * are quite a few of these, because we have two separate
1621 * mechanisms for delaying the sending of packets:
1623 * - In order to send an IGNORE message and a password message in
1624 * a single fixed-length blob, we require the ability to
1625 * concatenate the encrypted forms of those two packets _into_ a
1626 * single blob and then pass it to our <network.h> transport
1627 * layer in one go. Hence, there's a deferment mechanism which
1628 * works after packet encryption.
1630 * - In order to avoid sending any connection-layer messages
1631 * during repeat key exchange, we have to queue up any such
1632 * outgoing messages _before_ they are encrypted (and in
1633 * particular before they're allocated sequence numbers), and
1634 * then send them once we've finished.
1636 * I call these mechanisms `defer' and `queue' respectively, so as
1637 * to distinguish them reasonably easily.
1639 * The functions send_noqueue() and defer_noqueue() free the packet
1640 * structure they are passed. Every outgoing packet goes through
1641 * precisely one of these functions in its life; packets passed to
1642 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1643 * these or get queued, and then when the queue is later emptied
1644 * the packets are all passed to defer_noqueue().
1648 * Send an SSH2 packet immediately, without queuing or deferring.
1650 static void ssh2_pkt_send_noqueue(Ssh ssh
, struct Packet
*pkt
)
1654 len
= ssh2_pkt_construct(ssh
, pkt
);
1655 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1656 if (backlog
> SSH_MAX_BACKLOG
)
1657 ssh_throttle_all(ssh
, 1, backlog
);
1659 ssh
->outgoing_data_size
+= pkt
->encrypted_len
;
1660 if (!ssh
->kex_in_progress
&&
1661 ssh
->outgoing_data_size
> MAX_DATA_BEFORE_REKEY
)
1662 do_ssh2_transport(ssh
, "Initiating key re-exchange "
1663 "(too much data sent)", -1, NULL
);
1665 ssh_free_packet(pkt
);
1669 * Defer an SSH2 packet.
1671 static void ssh2_pkt_defer_noqueue(Ssh ssh
, struct Packet
*pkt
)
1673 int len
= ssh2_pkt_construct(ssh
, pkt
);
1674 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1675 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1676 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1680 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1681 ssh
->deferred_len
+= len
;
1682 ssh
->deferred_data_size
+= pkt
->encrypted_len
;
1683 ssh_free_packet(pkt
);
1687 * Queue an SSH2 packet.
1689 static void ssh2_pkt_queue(Ssh ssh
, struct Packet
*pkt
)
1691 assert(ssh
->queueing
);
1693 if (ssh
->queuelen
>= ssh
->queuesize
) {
1694 ssh
->queuesize
= ssh
->queuelen
+ 32;
1695 ssh
->queue
= sresize(ssh
->queue
, ssh
->queuesize
, struct Packet
*);
1698 ssh
->queue
[ssh
->queuelen
++] = pkt
;
1702 * Either queue or send a packet, depending on whether queueing is
1705 static void ssh2_pkt_send(Ssh ssh
, struct Packet
*pkt
)
1708 ssh2_pkt_queue(ssh
, pkt
);
1710 ssh2_pkt_send_noqueue(ssh
, pkt
);
1714 * Either queue or defer a packet, depending on whether queueing is
1717 static void ssh2_pkt_defer(Ssh ssh
, struct Packet
*pkt
)
1720 ssh2_pkt_queue(ssh
, pkt
);
1722 ssh2_pkt_defer_noqueue(ssh
, pkt
);
1726 * Send the whole deferred data block constructed by
1727 * ssh2_pkt_defer() or SSH1's defer_packet().
1729 * The expected use of the defer mechanism is that you call
1730 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1731 * not currently queueing, this simply sets up deferred_send_data
1732 * and then sends it. If we _are_ currently queueing, the calls to
1733 * ssh2_pkt_defer() put the deferred packets on to the queue
1734 * instead, and therefore ssh_pkt_defersend() has no deferred data
1735 * to send. Hence, there's no need to make it conditional on
1738 static void ssh_pkt_defersend(Ssh ssh
)
1741 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1743 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1744 sfree(ssh
->deferred_send_data
);
1745 ssh
->deferred_send_data
= NULL
;
1746 if (backlog
> SSH_MAX_BACKLOG
)
1747 ssh_throttle_all(ssh
, 1, backlog
);
1749 ssh
->outgoing_data_size
+= ssh
->deferred_data_size
;
1750 if (!ssh
->kex_in_progress
&&
1751 ssh
->outgoing_data_size
> MAX_DATA_BEFORE_REKEY
)
1752 do_ssh2_transport(ssh
, "Initiating key re-exchange "
1753 "(too much data sent)", -1, NULL
);
1754 ssh
->deferred_data_size
= 0;
1758 * Send all queued SSH2 packets. We send them by means of
1759 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1760 * packets that needed to be lumped together.
1762 static void ssh2_pkt_queuesend(Ssh ssh
)
1766 assert(!ssh
->queueing
);
1768 for (i
= 0; i
< ssh
->queuelen
; i
++)
1769 ssh2_pkt_defer_noqueue(ssh
, ssh
->queue
[i
]);
1772 ssh_pkt_defersend(ssh
);
1776 void bndebug(char *string
, Bignum b
)
1780 p
= ssh2_mpint_fmt(b
, &len
);
1781 debug(("%s", string
));
1782 for (i
= 0; i
< len
; i
++)
1783 debug((" %02x", p
[i
]));
1789 static void sha_mpint(SHA_State
* s
, Bignum b
)
1793 p
= ssh2_mpint_fmt(b
, &len
);
1794 sha_string(s
, p
, len
);
1799 * Packet decode functions for both SSH1 and SSH2.
1801 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
)
1803 unsigned long value
;
1804 if (pkt
->length
- pkt
->savedpos
< 4)
1805 return 0; /* arrgh, no way to decline (FIXME?) */
1806 value
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1810 static int ssh2_pkt_getbool(struct Packet
*pkt
)
1812 unsigned long value
;
1813 if (pkt
->length
- pkt
->savedpos
< 1)
1814 return 0; /* arrgh, no way to decline (FIXME?) */
1815 value
= pkt
->body
[pkt
->savedpos
] != 0;
1819 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
)
1824 if (pkt
->length
- pkt
->savedpos
< 4)
1826 len
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1831 if (pkt
->length
- pkt
->savedpos
< *length
)
1833 *p
= (char *)(pkt
->body
+ pkt
->savedpos
);
1834 pkt
->savedpos
+= *length
;
1836 static void *ssh_pkt_getdata(struct Packet
*pkt
, int length
)
1838 if (pkt
->length
- pkt
->savedpos
< length
)
1840 pkt
->savedpos
+= length
;
1841 return pkt
->body
+ (pkt
->savedpos
- length
);
1843 static int ssh1_pkt_getrsakey(struct Packet
*pkt
, struct RSAKey
*key
,
1844 unsigned char **keystr
)
1848 j
= makekey(pkt
->body
+ pkt
->savedpos
,
1849 pkt
->length
- pkt
->savedpos
,
1856 assert(pkt
->savedpos
< pkt
->length
);
1860 static Bignum
ssh1_pkt_getmp(struct Packet
*pkt
)
1865 j
= ssh1_read_bignum(pkt
->body
+ pkt
->savedpos
,
1866 pkt
->length
- pkt
->savedpos
, &b
);
1874 static Bignum
ssh2_pkt_getmp(struct Packet
*pkt
)
1880 ssh_pkt_getstring(pkt
, &p
, &length
);
1885 b
= bignum_from_bytes((unsigned char *)p
, length
);
1890 * Helper function to add an SSH2 signature blob to a packet.
1891 * Expects to be shown the public key blob as well as the signature
1892 * blob. Normally works just like ssh2_pkt_addstring, but will
1893 * fiddle with the signature packet if necessary for
1894 * BUG_SSH2_RSA_PADDING.
1896 static void ssh2_add_sigblob(Ssh ssh
, struct Packet
*pkt
,
1897 void *pkblob_v
, int pkblob_len
,
1898 void *sigblob_v
, int sigblob_len
)
1900 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1901 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1903 /* dmemdump(pkblob, pkblob_len); */
1904 /* dmemdump(sigblob, sigblob_len); */
1907 * See if this is in fact an ssh-rsa signature and a buggy
1908 * server; otherwise we can just do this the easy way.
1910 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1911 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1912 int pos
, len
, siglen
;
1915 * Find the byte length of the modulus.
1918 pos
= 4+7; /* skip over "ssh-rsa" */
1919 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1920 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
1921 pos
+= 4; /* find modulus itself */
1922 while (len
> 0 && pkblob
[pos
] == 0)
1924 /* debug(("modulus length is %d\n", len)); */
1927 * Now find the signature integer.
1929 pos
= 4+7; /* skip over "ssh-rsa" */
1930 siglen
= GET_32BIT(sigblob
+pos
);
1931 /* debug(("signature length is %d\n", siglen)); */
1933 if (len
!= siglen
) {
1934 unsigned char newlen
[4];
1935 ssh2_pkt_addstring_start(pkt
);
1936 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, pos
);
1937 /* dmemdump(sigblob, pos); */
1938 pos
+= 4; /* point to start of actual sig */
1939 PUT_32BIT(newlen
, len
);
1940 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 4);
1941 /* dmemdump(newlen, 4); */
1943 while (len
-- > siglen
) {
1944 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 1);
1945 /* dmemdump(newlen, 1); */
1947 ssh2_pkt_addstring_data(pkt
, (char *)(sigblob
+pos
), siglen
);
1948 /* dmemdump(sigblob+pos, siglen); */
1952 /* Otherwise fall through and do it the easy way. */
1955 ssh2_pkt_addstring_start(pkt
);
1956 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, sigblob_len
);
1960 * Examine the remote side's version string and compare it against
1961 * a list of known buggy implementations.
1963 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
1965 char *imp
; /* pointer to implementation part */
1967 imp
+= strcspn(imp
, "-");
1969 imp
+= strcspn(imp
, "-");
1972 ssh
->remote_bugs
= 0;
1974 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
1975 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
1976 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
1977 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
1978 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
1979 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
1981 * These versions don't support SSH1_MSG_IGNORE, so we have
1982 * to use a different defence against password length
1985 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
1986 logevent("We believe remote version has SSH1 ignore bug");
1989 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
1990 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
1991 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
1993 * These versions need a plain password sent; they can't
1994 * handle having a null and a random length of data after
1997 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
1998 logevent("We believe remote version needs a plain SSH1 password");
2001 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
2002 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
2003 (!strcmp(imp
, "Cisco-1.25")))) {
2005 * These versions apparently have no clue whatever about
2006 * RSA authentication and will panic and die if they see
2007 * an AUTH_RSA message.
2009 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
2010 logevent("We believe remote version can't handle RSA authentication");
2013 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
2014 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
2015 !wc_match("* VShell", imp
) &&
2016 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
2017 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
2018 wc_match("2.1 *", imp
)))) {
2020 * These versions have the HMAC bug.
2022 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
2023 logevent("We believe remote version has SSH2 HMAC bug");
2026 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2027 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2028 !wc_match("* VShell", imp
) &&
2029 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2031 * These versions have the key-derivation bug (failing to
2032 * include the literal shared secret in the hashes that
2033 * generate the keys).
2035 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2036 logevent("We believe remote version has SSH2 key-derivation bug");
2039 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2040 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2041 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2042 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2044 * These versions have the SSH2 RSA padding bug.
2046 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2047 logevent("We believe remote version has SSH2 RSA padding bug");
2050 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2051 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2052 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2054 * These versions have the SSH2 session-ID bug in
2055 * public-key authentication.
2057 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2058 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2061 if (ssh
->cfg
.sshbug_dhgex2
== FORCE_ON
) {
2063 * User specified the SSH2 DH GEX bug.
2065 ssh
->remote_bugs
|= BUG_SSH2_DH_GEX
;
2066 logevent("We believe remote version has SSH2 DH group exchange bug");
2070 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2072 struct do_ssh_init_state
{
2080 crState(do_ssh_init_state
);
2082 crBegin(ssh
->do_ssh_init_crstate
);
2084 /* Search for the string "SSH-" in the input. */
2087 static const int transS
[] = { 1, 2, 2, 1 };
2088 static const int transH
[] = { 0, 0, 3, 0 };
2089 static const int transminus
[] = { 0, 0, 0, -1 };
2091 s
->i
= transS
[s
->i
];
2093 s
->i
= transH
[s
->i
];
2095 s
->i
= transminus
[s
->i
];
2100 crReturn(1); /* get another character */
2104 s
->vstring
= snewn(s
->vstrsize
, char);
2105 strcpy(s
->vstring
, "SSH-");
2109 crReturn(1); /* get another char */
2110 if (s
->vslen
>= s
->vstrsize
- 1) {
2112 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2114 s
->vstring
[s
->vslen
++] = c
;
2117 s
->version
[s
->i
] = '\0';
2119 } else if (s
->i
< sizeof(s
->version
) - 1)
2120 s
->version
[s
->i
++] = c
;
2121 } else if (c
== '\012')
2125 ssh
->agentfwd_enabled
= FALSE
;
2126 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2128 s
->vstring
[s
->vslen
] = 0;
2129 s
->vstring
[strcspn(s
->vstring
, "\r\n")] = '\0';/* remove EOL chars */
2132 vlog
= snewn(20 + s
->vslen
, char);
2133 sprintf(vlog
, "Server version: %s", s
->vstring
);
2137 ssh_detect_bugs(ssh
, s
->vstring
);
2140 * Decide which SSH protocol version to support.
2143 /* Anything strictly below "2.0" means protocol 1 is supported. */
2144 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2145 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2146 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2148 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2149 bombout(("SSH protocol version 1 required by user but not provided by server"));
2152 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2153 bombout(("SSH protocol version 2 required by user but not provided by server"));
2157 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2161 char verstring
[80], vlog
[100];
2162 sprintf(verstring
, "SSH-2.0-%s", sshver
);
2163 SHA_Init(&ssh
->exhashbase
);
2165 * Hash our version string and their version string.
2167 sha_string(&ssh
->exhashbase
, verstring
, strlen(verstring
));
2168 sha_string(&ssh
->exhashbase
, s
->vstring
, strcspn(s
->vstring
, "\r\n"));
2169 sprintf(vlog
, "We claim version: %s", verstring
);
2171 strcat(verstring
, "\012");
2172 logevent("Using SSH protocol version 2");
2173 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2174 ssh
->protocol
= ssh2_protocol
;
2175 ssh2_protocol_setup(ssh
);
2177 ssh
->s_rdpkt
= ssh2_rdpkt
;
2182 char verstring
[80], vlog
[100];
2183 sprintf(verstring
, "SSH-%s-%s",
2184 (ssh_versioncmp(s
->version
, "1.5") <= 0 ? s
->version
: "1.5"),
2186 sprintf(vlog
, "We claim version: %s", verstring
);
2188 strcat(verstring
, "\012");
2190 logevent("Using SSH protocol version 1");
2191 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2192 ssh
->protocol
= ssh1_protocol
;
2193 ssh1_protocol_setup(ssh
);
2195 ssh
->s_rdpkt
= ssh1_rdpkt
;
2197 update_specials_menu(ssh
->frontend
);
2198 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2199 ssh
->pinger
= pinger_new(&ssh
->cfg
, &ssh_backend
, ssh
);
2206 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2208 crBegin(ssh
->ssh_gotdata_crstate
);
2211 * To begin with, feed the characters one by one to the
2212 * protocol initialisation / selection function do_ssh_init().
2213 * When that returns 0, we're done with the initial greeting
2214 * exchange and can move on to packet discipline.
2217 int ret
; /* need not be kept across crReturn */
2219 crReturnV
; /* more data please */
2220 ret
= do_ssh_init(ssh
, *data
);
2228 * We emerge from that loop when the initial negotiation is
2229 * over and we have selected an s_rdpkt function. Now pass
2230 * everything to s_rdpkt, and then pass the resulting packets
2231 * to the proper protocol handler.
2236 while (datalen
> 0) {
2237 struct Packet
*pktin
= ssh
->s_rdpkt(ssh
, &data
, &datalen
);
2239 ssh
->protocol(ssh
, NULL
, 0, pktin
);
2240 ssh_free_packet(pktin
);
2242 if (ssh
->state
== SSH_STATE_CLOSED
)
2250 static void ssh_do_close(Ssh ssh
)
2253 struct ssh_channel
*c
;
2255 ssh
->state
= SSH_STATE_CLOSED
;
2259 notify_remote_exit(ssh
->frontend
);
2262 * Now we must shut down any port and X forwardings going
2263 * through this connection.
2265 if (ssh
->channels
) {
2266 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2269 x11_close(c
->u
.x11
.s
);
2272 pfd_close(c
->u
.pfd
.s
);
2275 del234(ssh
->channels
, c
);
2276 if (ssh
->version
== 2)
2277 bufchain_clear(&c
->v
.v2
.outbuffer
);
2283 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2286 Ssh ssh
= (Ssh
) plug
;
2289 /* A socket error has occurred. */
2290 logevent(error_msg
);
2291 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2293 /* Otherwise, the remote side closed the connection normally. */
2298 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2300 Ssh ssh
= (Ssh
) plug
;
2301 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2302 if (ssh
->state
== SSH_STATE_CLOSED
) {
2309 static void ssh_sent(Plug plug
, int bufsize
)
2311 Ssh ssh
= (Ssh
) plug
;
2313 * If the send backlog on the SSH socket itself clears, we
2314 * should unthrottle the whole world if it was throttled.
2316 if (bufsize
< SSH_MAX_BACKLOG
)
2317 ssh_throttle_all(ssh
, 0, bufsize
);
2321 * Connect to specified host and port.
2322 * Returns an error message, or NULL on success.
2323 * Also places the canonical host name into `realhost'. It must be
2324 * freed by the caller.
2326 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2327 char **realhost
, int nodelay
, int keepalive
)
2329 static const struct plug_function_table fn_table
= {
2339 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2340 if (!ssh
->savedhost
)
2341 fatalbox("Out of memory");
2342 strcpy(ssh
->savedhost
, host
);
2345 port
= 22; /* default ssh port */
2346 ssh
->savedport
= port
;
2351 logeventf(ssh
, "Looking up host \"%s\"", host
);
2352 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
);
2353 if ((err
= sk_addr_error(addr
)) != NULL
) {
2363 sk_getaddr(addr
, addrbuf
, 100);
2364 logeventf(ssh
, "Connecting to %s port %d", addrbuf
, port
);
2366 ssh
->fn
= &fn_table
;
2367 ssh
->s
= new_connection(addr
, *realhost
, port
,
2368 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2369 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2371 notify_remote_exit(ssh
->frontend
);
2379 * Throttle or unthrottle the SSH connection.
2381 static void ssh1_throttle(Ssh ssh
, int adjust
)
2383 int old_count
= ssh
->v1_throttle_count
;
2384 ssh
->v1_throttle_count
+= adjust
;
2385 assert(ssh
->v1_throttle_count
>= 0);
2386 if (ssh
->v1_throttle_count
&& !old_count
) {
2387 sk_set_frozen(ssh
->s
, 1);
2388 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2389 sk_set_frozen(ssh
->s
, 0);
2394 * Throttle or unthrottle _all_ local data streams (for when sends
2395 * on the SSH connection itself back up).
2397 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2400 struct ssh_channel
*c
;
2402 if (enable
== ssh
->throttled_all
)
2404 ssh
->throttled_all
= enable
;
2405 ssh
->overall_bufsize
= bufsize
;
2408 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2410 case CHAN_MAINSESSION
:
2412 * This is treated separately, outside the switch.
2416 x11_override_throttle(c
->u
.x11
.s
, enable
);
2419 /* Agent channels require no buffer management. */
2422 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2429 * Username and password input, abstracted off into routines
2430 * reusable in several places - even between SSH1 and SSH2.
2433 /* Set up a username or password input loop on a given buffer. */
2434 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2436 ssh
->userpass_input_buffer
= buffer
;
2437 ssh
->userpass_input_buflen
= buflen
;
2438 ssh
->userpass_input_bufpos
= 0;
2439 ssh
->userpass_input_echo
= echo
;
2443 * Process some terminal data in the course of username/password
2444 * input. Returns >0 for success (line of input returned in
2445 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2446 * for inconclusive (keep waiting for more input please).
2448 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2453 switch (c
= *in
++) {
2456 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2457 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2462 if (ssh
->userpass_input_bufpos
> 0) {
2463 if (ssh
->userpass_input_echo
)
2464 c_write_str(ssh
, "\b \b");
2465 ssh
->userpass_input_bufpos
--;
2470 while (ssh
->userpass_input_bufpos
> 0) {
2471 if (ssh
->userpass_input_echo
)
2472 c_write_str(ssh
, "\b \b");
2473 ssh
->userpass_input_bufpos
--;
2482 * This simplistic check for printability is disabled
2483 * when we're doing password input, because some people
2484 * have control characters in their passwords.o
2486 if ((!ssh
->userpass_input_echo
||
2487 (c
>= ' ' && c
<= '~') ||
2488 ((unsigned char) c
>= 160))
2489 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2490 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2491 if (ssh
->userpass_input_echo
)
2492 c_write(ssh
, &c
, 1);
2500 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2502 Ssh ssh
= (Ssh
) sshv
;
2504 ssh
->agent_response
= reply
;
2505 ssh
->agent_response_len
= replylen
;
2507 if (ssh
->version
== 1)
2508 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2510 do_ssh2_authconn(ssh
, NULL
, -1, NULL
);
2513 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2515 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2517 void *sentreply
= reply
;
2520 /* Fake SSH_AGENT_FAILURE. */
2521 sentreply
= "\0\0\0\1\5";
2524 if (ssh
->version
== 2) {
2525 ssh2_add_channel_data(c
, sentreply
, replylen
);
2528 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2529 PKT_INT
, c
->remoteid
,
2532 PKT_DATA
, sentreply
, replylen
,
2541 * Handle the key exchange and user authentication phases.
2543 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
2544 struct Packet
*pktin
)
2547 unsigned char cookie
[8], *ptr
;
2548 struct RSAKey servkey
, hostkey
;
2549 struct MD5Context md5c
;
2550 struct do_ssh1_login_state
{
2552 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2553 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2554 int tried_publickey
, tried_agent
;
2555 int tis_auth_refused
, ccard_auth_refused
;
2556 unsigned char session_id
[16];
2559 void *publickey_blob
;
2560 int publickey_bloblen
;
2566 unsigned char request
[5], *response
, *p
;
2575 crState(do_ssh1_login_state
);
2577 crBegin(ssh
->do_ssh1_login_crstate
);
2584 if (pktin
->type
!= SSH1_SMSG_PUBLIC_KEY
) {
2585 bombout(("Public key packet not received"));
2589 logevent("Received public keys");
2591 ptr
= ssh_pkt_getdata(pktin
, 8);
2593 bombout(("SSH1 public key packet stopped before random cookie"));
2596 memcpy(cookie
, ptr
, 8);
2598 if (!ssh1_pkt_getrsakey(pktin
, &servkey
, &s
->keystr1
) ||
2599 !ssh1_pkt_getrsakey(pktin
, &hostkey
, &s
->keystr2
)) {
2600 bombout(("Failed to read SSH1 public keys from public key packet"));
2605 * Log the host key fingerprint.
2609 logevent("Host key fingerprint is:");
2610 strcpy(logmsg
, " ");
2611 hostkey
.comment
= NULL
;
2612 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2613 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2617 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(pktin
);
2618 s
->supported_ciphers_mask
= ssh_pkt_getuint32(pktin
);
2619 s
->supported_auths_mask
= ssh_pkt_getuint32(pktin
);
2621 ssh
->v1_local_protoflags
=
2622 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2623 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2626 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2627 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2628 MD5Update(&md5c
, cookie
, 8);
2629 MD5Final(s
->session_id
, &md5c
);
2631 for (i
= 0; i
< 32; i
++)
2632 ssh
->session_key
[i
] = random_byte();
2635 * Verify that the `bits' and `bytes' parameters match.
2637 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
2638 servkey
.bits
> servkey
.bytes
* 8) {
2639 bombout(("SSH1 public keys were badly formatted"));
2643 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2645 s
->rsabuf
= snewn(s
->len
, unsigned char);
2647 fatalbox("Out of memory");
2650 * Verify the host key.
2654 * First format the key into a string.
2656 int len
= rsastr_len(&hostkey
);
2657 char fingerprint
[100];
2658 char *keystr
= snewn(len
, char);
2660 fatalbox("Out of memory");
2661 rsastr_fmt(keystr
, &hostkey
);
2662 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2663 verify_ssh_host_key(ssh
->frontend
,
2664 ssh
->savedhost
, ssh
->savedport
, "rsa", keystr
,
2669 for (i
= 0; i
< 32; i
++) {
2670 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2672 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2675 if (hostkey
.bytes
> servkey
.bytes
) {
2676 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
2678 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2680 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2682 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2685 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2689 logevent("Encrypted session key");
2692 int cipher_chosen
= 0, warn
= 0;
2693 char *cipher_string
= NULL
;
2695 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2696 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
2697 if (next_cipher
== CIPHER_WARN
) {
2698 /* If/when we choose a cipher, warn about it */
2700 } else if (next_cipher
== CIPHER_AES
) {
2701 /* XXX Probably don't need to mention this. */
2702 logevent("AES not supported in SSH1, skipping");
2704 switch (next_cipher
) {
2705 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2706 cipher_string
= "3DES"; break;
2707 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2708 cipher_string
= "Blowfish"; break;
2709 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2710 cipher_string
= "single-DES"; break;
2712 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2716 if (!cipher_chosen
) {
2717 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2718 bombout(("Server violates SSH 1 protocol by not "
2719 "supporting 3DES encryption"));
2721 /* shouldn't happen */
2722 bombout(("No supported ciphers found"));
2726 /* Warn about chosen cipher if necessary. */
2728 askcipher(ssh
->frontend
, cipher_string
, 0);
2731 switch (s
->cipher_type
) {
2732 case SSH_CIPHER_3DES
:
2733 logevent("Using 3DES encryption");
2735 case SSH_CIPHER_DES
:
2736 logevent("Using single-DES encryption");
2738 case SSH_CIPHER_BLOWFISH
:
2739 logevent("Using Blowfish encryption");
2743 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
2744 PKT_CHAR
, s
->cipher_type
,
2745 PKT_DATA
, cookie
, 8,
2746 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
2747 PKT_DATA
, s
->rsabuf
, s
->len
,
2748 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
2750 logevent("Trying to enable encryption...");
2754 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2755 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
2757 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
2758 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
2759 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
2761 ssh
->crcda_ctx
= crcda_make_context();
2762 logevent("Installing CRC compensation attack detector");
2764 if (servkey
.modulus
) {
2765 sfree(servkey
.modulus
);
2766 servkey
.modulus
= NULL
;
2768 if (servkey
.exponent
) {
2769 sfree(servkey
.exponent
);
2770 servkey
.exponent
= NULL
;
2772 if (hostkey
.modulus
) {
2773 sfree(hostkey
.modulus
);
2774 hostkey
.modulus
= NULL
;
2776 if (hostkey
.exponent
) {
2777 sfree(hostkey
.exponent
);
2778 hostkey
.exponent
= NULL
;
2782 if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
2783 bombout(("Encryption not successfully enabled"));
2787 logevent("Successfully started encryption");
2791 if (!*ssh
->cfg
.username
) {
2792 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2793 if (!ssh_get_line("login as: ",
2794 s
->username
, sizeof(s
->username
), FALSE
)) {
2796 * get_line failed to get a username.
2799 logevent("No username provided. Abandoning session.");
2800 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2804 int ret
; /* need not be kept over crReturn */
2805 c_write_str(ssh
, "login as: ");
2808 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
2810 crWaitUntil(!pktin
);
2811 ret
= process_userpass_input(ssh
, in
, inlen
);
2815 c_write_str(ssh
, "\r\n");
2818 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
2819 s
->username
[sizeof(s
->username
)-1] = '\0';
2822 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
2824 char userlog
[22 + sizeof(s
->username
)];
2825 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
2827 if (flags
& FLAG_INTERACTIVE
&&
2828 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2829 strcat(userlog
, "\r\n");
2830 c_write_str(ssh
, userlog
);
2837 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2838 /* We must not attempt PK auth. Pretend we've already tried it. */
2839 s
->tried_publickey
= s
->tried_agent
= 1;
2841 s
->tried_publickey
= s
->tried_agent
= 0;
2843 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
2844 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
2845 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
2846 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
2847 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
2848 s
->publickey_blob
= NULL
;
2850 s
->publickey_blob
= NULL
;
2852 while (pktin
->type
== SSH1_SMSG_FAILURE
) {
2853 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2855 if (agent_exists() && !s
->tried_agent
) {
2857 * Attempt RSA authentication using Pageant.
2863 logevent("Pageant is running. Requesting keys.");
2865 /* Request the keys held by the agent. */
2866 PUT_32BIT(s
->request
, 1);
2867 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2868 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
2869 ssh_agent_callback
, ssh
)) {
2873 bombout(("Unexpected data from server while waiting"
2874 " for agent response"));
2877 } while (pktin
|| inlen
> 0);
2878 r
= ssh
->agent_response
;
2879 s
->responselen
= ssh
->agent_response_len
;
2881 s
->response
= (unsigned char *) r
;
2882 if (s
->response
&& s
->responselen
>= 5 &&
2883 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
2884 s
->p
= s
->response
+ 5;
2885 s
->nkeys
= GET_32BIT(s
->p
);
2889 sprintf(buf
, "Pageant has %d SSH1 keys", s
->nkeys
);
2892 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
2895 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
2898 if (s
->publickey_blob
&&
2899 !memcmp(s
->p
, s
->publickey_blob
,
2900 s
->publickey_bloblen
)) {
2901 logevent("This key matches configured key file");
2902 s
->tried_publickey
= 1;
2907 do { /* do while (0) to make breaking easy */
2908 n
= ssh1_read_bignum
2909 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
2914 n
= ssh1_read_bignum
2915 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
2920 if (s
->responselen
- (s
->p
-s
->response
) < 4)
2922 s
->commentlen
= GET_32BIT(s
->p
);
2924 if (s
->responselen
- (s
->p
-s
->response
) <
2927 s
->commentp
= (char *)s
->p
;
2928 s
->p
+= s
->commentlen
;
2932 logevent("Pageant key list packet was truncated");
2936 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
2937 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
2939 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2940 logevent("Key refused");
2943 logevent("Received RSA challenge");
2944 if ((s
->challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
2945 bombout(("Server's RSA challenge was badly formatted"));
2950 char *agentreq
, *q
, *ret
;
2953 len
= 1 + 4; /* message type, bit count */
2954 len
+= ssh1_bignum_length(s
->key
.exponent
);
2955 len
+= ssh1_bignum_length(s
->key
.modulus
);
2956 len
+= ssh1_bignum_length(s
->challenge
);
2957 len
+= 16; /* session id */
2958 len
+= 4; /* response format */
2959 agentreq
= snewn(4 + len
, char);
2960 PUT_32BIT(agentreq
, len
);
2962 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
2963 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
2965 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
2966 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
2967 q
+= ssh1_write_bignum(q
, s
->challenge
);
2968 memcpy(q
, s
->session_id
, 16);
2970 PUT_32BIT(q
, 1); /* response format */
2971 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
2972 ssh_agent_callback
, ssh
)) {
2977 bombout(("Unexpected data from server"
2978 " while waiting for agent"
2982 } while (pktin
|| inlen
> 0);
2983 vret
= ssh
->agent_response
;
2984 retlen
= ssh
->agent_response_len
;
2989 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
2990 logevent("Sending Pageant's response");
2991 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
2992 PKT_DATA
, ret
+ 5, 16,
2996 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
2998 ("Pageant's response accepted");
2999 if (flags
& FLAG_VERBOSE
) {
3000 c_write_str(ssh
, "Authenticated using"
3002 c_write(ssh
, s
->commentp
,
3004 c_write_str(ssh
, "\" from agent\r\n");
3009 ("Pageant's response not accepted");
3012 ("Pageant failed to answer challenge");
3016 logevent("No reply received from Pageant");
3019 freebn(s
->key
.exponent
);
3020 freebn(s
->key
.modulus
);
3021 freebn(s
->challenge
);
3030 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
3031 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
3033 if (ssh
->cfg
.try_tis_auth
&&
3034 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3035 !s
->tis_auth_refused
) {
3036 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3037 logevent("Requested TIS authentication");
3038 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3040 if (pktin
->type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3041 logevent("TIS authentication declined");
3042 if (flags
& FLAG_INTERACTIVE
)
3043 c_write_str(ssh
, "TIS authentication refused.\r\n");
3044 s
->tis_auth_refused
= 1;
3050 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3052 bombout(("TIS challenge packet was badly formed"));
3055 logevent("Received TIS challenge");
3056 if (challengelen
> sizeof(s
->prompt
) - 1)
3057 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3058 memcpy(s
->prompt
, challenge
, challengelen
);
3059 /* Prompt heuristic comes from OpenSSH */
3060 strncpy(s
->prompt
+ challengelen
,
3061 memchr(s
->prompt
, '\n', challengelen
) ?
3062 "": "\r\nResponse: ",
3063 (sizeof s
->prompt
) - challengelen
);
3064 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
3067 if (ssh
->cfg
.try_tis_auth
&&
3068 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3069 !s
->ccard_auth_refused
) {
3070 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3071 logevent("Requested CryptoCard authentication");
3072 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3074 if (pktin
->type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3075 logevent("CryptoCard authentication declined");
3076 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3077 s
->ccard_auth_refused
= 1;
3083 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3085 bombout(("CryptoCard challenge packet was badly formed"));
3088 logevent("Received CryptoCard challenge");
3089 if (challengelen
> sizeof(s
->prompt
) - 1)
3090 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3091 memcpy(s
->prompt
, challenge
, challengelen
);
3092 strncpy(s
->prompt
+ challengelen
,
3093 memchr(s
->prompt
, '\n', challengelen
) ?
3094 "" : "\r\nResponse: ",
3095 sizeof(s
->prompt
) - challengelen
);
3096 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
3099 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3100 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
3101 s
->username
, ssh
->savedhost
);
3103 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3104 char *comment
= NULL
;
3107 if (flags
& FLAG_VERBOSE
)
3108 c_write_str(ssh
, "Trying public key authentication.\r\n");
3109 logeventf(ssh
, "Trying public key \"%s\"",
3110 filename_to_str(&ssh
->cfg
.keyfile
));
3111 type
= key_type(&ssh
->cfg
.keyfile
);
3112 if (type
!= SSH_KEYTYPE_SSH1
) {
3113 sprintf(msgbuf
, "Key is of wrong type (%s)",
3114 key_type_to_str(type
));
3116 c_write_str(ssh
, msgbuf
);
3117 c_write_str(ssh
, "\r\n");
3118 s
->tried_publickey
= 1;
3121 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
3122 if (flags
& FLAG_VERBOSE
)
3123 c_write_str(ssh
, "No passphrase required.\r\n");
3126 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
3131 * Show password prompt, having first obtained it via a TIS
3132 * or CryptoCard exchange if we're doing TIS or CryptoCard
3136 if (!ssh_get_line(s
->prompt
, s
->password
,
3137 sizeof(s
->password
), TRUE
)) {
3139 * get_line failed to get a password (for example
3140 * because one was supplied on the command line
3141 * which has already failed to work). Terminate.
3143 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
3144 PKT_STR
, "No more passwords available to try",
3146 logevent("Unable to authenticate");
3147 connection_fatal(ssh
->frontend
, "Unable to authenticate");
3148 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3152 /* Prompt may have come from server. We've munged it a bit, so
3153 * we know it to be zero-terminated at least once. */
3154 int ret
; /* need not be saved over crReturn */
3155 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3158 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3160 crWaitUntil(!pktin
);
3161 ret
= process_userpass_input(ssh
, in
, inlen
);
3165 c_write_str(ssh
, "\r\n");
3169 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3171 * Try public key authentication with the specified
3174 s
->tried_publickey
= 1;
3177 const char *error
= NULL
;
3178 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3181 c_write_str(ssh
, "Couldn't load private key from ");
3182 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3183 c_write_str(ssh
, " (");
3184 c_write_str(ssh
, error
);
3185 c_write_str(ssh
, ").\r\n");
3186 continue; /* go and try password */
3189 c_write_str(ssh
, "Wrong passphrase.\r\n");
3190 s
->tried_publickey
= 0;
3191 continue; /* try again */
3196 * Send a public key attempt.
3198 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3199 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3202 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3203 c_write_str(ssh
, "Server refused our public key.\r\n");
3204 continue; /* go and try password */
3206 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3207 bombout(("Bizarre response to offer of public key"));
3213 unsigned char buffer
[32];
3214 Bignum challenge
, response
;
3216 if ((challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3217 bombout(("Server's RSA challenge was badly formatted"));
3220 response
= rsadecrypt(challenge
, &s
->key
);
3221 freebn(s
->key
.private_exponent
);/* burn the evidence */
3223 for (i
= 0; i
< 32; i
++) {
3224 buffer
[i
] = bignum_byte(response
, 31 - i
);
3228 MD5Update(&md5c
, buffer
, 32);
3229 MD5Update(&md5c
, s
->session_id
, 16);
3230 MD5Final(buffer
, &md5c
);
3232 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3233 PKT_DATA
, buffer
, 16, PKT_END
);
3240 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3241 if (flags
& FLAG_VERBOSE
)
3242 c_write_str(ssh
, "Failed to authenticate with"
3243 " our public key.\r\n");
3244 continue; /* go and try password */
3245 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3246 bombout(("Bizarre response to RSA authentication response"));
3250 break; /* we're through! */
3252 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3254 * Defence against traffic analysis: we send a
3255 * whole bunch of packets containing strings of
3256 * different lengths. One of these strings is the
3257 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3258 * The others are all random data in
3259 * SSH1_MSG_IGNORE packets. This way a passive
3260 * listener can't tell which is the password, and
3261 * hence can't deduce the password length.
3263 * Anybody with a password length greater than 16
3264 * bytes is going to have enough entropy in their
3265 * password that a listener won't find it _that_
3266 * much help to know how long it is. So what we'll
3269 * - if password length < 16, we send 15 packets
3270 * containing string lengths 1 through 15
3272 * - otherwise, we let N be the nearest multiple
3273 * of 8 below the password length, and send 8
3274 * packets containing string lengths N through
3275 * N+7. This won't obscure the order of
3276 * magnitude of the password length, but it will
3277 * introduce a bit of extra uncertainty.
3279 * A few servers (the old 1.2.18 through 1.2.22)
3280 * can't deal with SSH1_MSG_IGNORE. For these
3281 * servers, we need an alternative defence. We make
3282 * use of the fact that the password is interpreted
3283 * as a C string: so we can append a NUL, then some
3286 * One server (a Cisco one) can deal with neither
3287 * SSH1_MSG_IGNORE _nor_ a padded password string.
3288 * For this server we are left with no defences
3289 * against password length sniffing.
3291 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3293 * The server can deal with SSH1_MSG_IGNORE, so
3294 * we can use the primary defence.
3296 int bottom
, top
, pwlen
, i
;
3299 pwlen
= strlen(s
->password
);
3301 bottom
= 0; /* zero length passwords are OK! :-) */
3304 bottom
= pwlen
& ~7;
3308 assert(pwlen
>= bottom
&& pwlen
<= top
);
3310 randomstr
= snewn(top
+ 1, char);
3312 for (i
= bottom
; i
<= top
; i
++) {
3314 defer_packet(ssh
, s
->pwpkt_type
,
3315 PKTT_PASSWORD
, PKT_STR
, s
->password
,
3316 PKTT_OTHER
, PKT_END
);
3318 for (j
= 0; j
< i
; j
++) {
3320 randomstr
[j
] = random_byte();
3321 } while (randomstr
[j
] == '\0');
3323 randomstr
[i
] = '\0';
3324 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3325 PKT_STR
, randomstr
, PKT_END
);
3328 logevent("Sending password with camouflage packets");
3329 ssh_pkt_defersend(ssh
);
3332 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3334 * The server can't deal with SSH1_MSG_IGNORE
3335 * but can deal with padded passwords, so we
3336 * can use the secondary defence.
3342 len
= strlen(s
->password
);
3343 if (len
< sizeof(string
)) {
3345 strcpy(string
, s
->password
);
3346 len
++; /* cover the zero byte */
3347 while (len
< sizeof(string
)) {
3348 string
[len
++] = (char) random_byte();
3353 logevent("Sending length-padded password");
3354 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3355 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3356 PKTT_OTHER
, PKT_END
);
3359 * The server has _both_
3360 * BUG_CHOKES_ON_SSH1_IGNORE and
3361 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3362 * therefore nothing we can do.
3365 len
= strlen(s
->password
);
3366 logevent("Sending unpadded password");
3367 send_packet(ssh
, s
->pwpkt_type
,
3368 PKTT_PASSWORD
, PKT_INT
, len
,
3369 PKT_DATA
, s
->password
, len
,
3370 PKTT_OTHER
, PKT_END
);
3373 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3374 PKT_STR
, s
->password
, PKTT_OTHER
, PKT_END
);
3377 logevent("Sent password");
3378 memset(s
->password
, 0, strlen(s
->password
));
3380 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3381 if (flags
& FLAG_VERBOSE
)
3382 c_write_str(ssh
, "Access denied\r\n");
3383 logevent("Authentication refused");
3384 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3385 bombout(("Strange packet received, type %d", pktin
->type
));
3390 logevent("Authentication successful");
3395 void sshfwd_close(struct ssh_channel
*c
)
3399 if (ssh
->state
!= SSH_STATE_SESSION
) {
3400 assert(ssh
->state
== SSH_STATE_CLOSED
);
3404 if (c
&& !c
->closes
) {
3406 * If the channel's remoteid is -1, we have sent
3407 * CHANNEL_OPEN for this channel, but it hasn't even been
3408 * acknowledged by the server. So we must set a close flag
3409 * on it now, and then when the server acks the channel
3410 * open, we can close it then.
3412 if (((int)c
->remoteid
) != -1) {
3413 if (ssh
->version
== 1) {
3414 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3417 struct Packet
*pktout
;
3418 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3419 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
3420 ssh2_pkt_send(ssh
, pktout
);
3423 c
->closes
= 1; /* sent MSG_CLOSE */
3424 if (c
->type
== CHAN_X11
) {
3426 logevent("Forwarded X11 connection terminated");
3427 } else if (c
->type
== CHAN_SOCKDATA
||
3428 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3430 logevent("Forwarded port closed");
3435 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3439 if (ssh
->state
!= SSH_STATE_SESSION
) {
3440 assert(ssh
->state
== SSH_STATE_CLOSED
);
3444 if (ssh
->version
== 1) {
3445 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3446 PKT_INT
, c
->remoteid
,
3448 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3449 PKTT_OTHER
, PKT_END
);
3451 * In SSH1 we can return 0 here - implying that forwarded
3452 * connections are never individually throttled - because
3453 * the only circumstance that can cause throttling will be
3454 * the whole SSH connection backing up, in which case
3455 * _everything_ will be throttled as a whole.
3459 ssh2_add_channel_data(c
, buf
, len
);
3460 return ssh2_try_send(c
);
3464 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3468 if (ssh
->state
!= SSH_STATE_SESSION
) {
3469 assert(ssh
->state
== SSH_STATE_CLOSED
);
3473 if (ssh
->version
== 1) {
3474 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3475 c
->v
.v1
.throttling
= 0;
3476 ssh1_throttle(ssh
, -1);
3479 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3483 static void ssh1_smsg_stdout_stderr_data(Ssh ssh
, struct Packet
*pktin
)
3486 int stringlen
, bufsize
;
3488 ssh_pkt_getstring(pktin
, &string
, &stringlen
);
3489 if (string
== NULL
) {
3490 bombout(("Incoming terminal data packet was badly formed"));
3494 bufsize
= from_backend(ssh
->frontend
, pktin
->type
== SSH1_SMSG_STDERR_DATA
,
3496 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3497 ssh
->v1_stdout_throttling
= 1;
3498 ssh1_throttle(ssh
, +1);
3502 static void ssh1_smsg_x11_open(Ssh ssh
, struct Packet
*pktin
)
3504 /* Remote side is trying to open a channel to talk to our
3505 * X-Server. Give them back a local channel number. */
3506 struct ssh_channel
*c
;
3507 int remoteid
= ssh_pkt_getuint32(pktin
);
3509 logevent("Received X11 connect request");
3510 /* Refuse if X11 forwarding is disabled. */
3511 if (!ssh
->X11_fwd_enabled
) {
3512 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3513 PKT_INT
, remoteid
, PKT_END
);
3514 logevent("Rejected X11 connect request");
3516 c
= snew(struct ssh_channel
);
3519 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
3520 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
3521 logevent("Opening X11 forward connection failed");
3523 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3524 PKT_INT
, remoteid
, PKT_END
);
3527 ("Opening X11 forward connection succeeded");
3528 c
->remoteid
= remoteid
;
3529 c
->localid
= alloc_channel_id(ssh
);
3531 c
->v
.v1
.throttling
= 0;
3532 c
->type
= CHAN_X11
; /* identify channel type */
3533 add234(ssh
->channels
, c
);
3534 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3535 PKT_INT
, c
->remoteid
, PKT_INT
,
3536 c
->localid
, PKT_END
);
3537 logevent("Opened X11 forward channel");
3542 static void ssh1_smsg_agent_open(Ssh ssh
, struct Packet
*pktin
)
3544 /* Remote side is trying to open a channel to talk to our
3545 * agent. Give them back a local channel number. */
3546 struct ssh_channel
*c
;
3547 int remoteid
= ssh_pkt_getuint32(pktin
);
3549 /* Refuse if agent forwarding is disabled. */
3550 if (!ssh
->agentfwd_enabled
) {
3551 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3552 PKT_INT
, remoteid
, PKT_END
);
3554 c
= snew(struct ssh_channel
);
3556 c
->remoteid
= remoteid
;
3557 c
->localid
= alloc_channel_id(ssh
);
3559 c
->v
.v1
.throttling
= 0;
3560 c
->type
= CHAN_AGENT
; /* identify channel type */
3561 c
->u
.a
.lensofar
= 0;
3562 add234(ssh
->channels
, c
);
3563 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3564 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
3569 static void ssh1_msg_port_open(Ssh ssh
, struct Packet
*pktin
)
3571 /* Remote side is trying to open a channel to talk to a
3572 * forwarded port. Give them back a local channel number. */
3573 struct ssh_channel
*c
;
3574 struct ssh_rportfwd pf
;
3577 char *host
, buf
[1024];
3579 c
= snew(struct ssh_channel
);
3582 remoteid
= ssh_pkt_getuint32(pktin
);
3583 ssh_pkt_getstring(pktin
, &host
, &hostsize
);
3584 port
= ssh_pkt_getuint32(pktin
);
3586 if (hostsize
>= lenof(pf
.dhost
))
3587 hostsize
= lenof(pf
.dhost
)-1;
3588 memcpy(pf
.dhost
, host
, hostsize
);
3589 pf
.dhost
[hostsize
] = '\0';
3592 if (find234(ssh
->rportfwds
, &pf
, NULL
) == NULL
) {
3593 sprintf(buf
, "Rejected remote port open request for %s:%d",
3596 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3597 PKT_INT
, remoteid
, PKT_END
);
3599 sprintf(buf
, "Received remote port open request for %s:%d",
3602 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
3606 sprintf(buf
, "Port open failed: %s", e
);
3609 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3610 PKT_INT
, remoteid
, PKT_END
);
3612 c
->remoteid
= remoteid
;
3613 c
->localid
= alloc_channel_id(ssh
);
3615 c
->v
.v1
.throttling
= 0;
3616 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
3617 add234(ssh
->channels
, c
);
3618 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3619 PKT_INT
, c
->remoteid
, PKT_INT
,
3620 c
->localid
, PKT_END
);
3621 logevent("Forwarded port opened successfully");
3626 static void ssh1_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
3628 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
3629 unsigned int localid
= ssh_pkt_getuint32(pktin
);
3630 struct ssh_channel
*c
;
3632 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
3633 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3634 c
->remoteid
= localid
;
3635 c
->type
= CHAN_SOCKDATA
;
3636 c
->v
.v1
.throttling
= 0;
3637 pfd_confirm(c
->u
.pfd
.s
);
3640 if (c
&& c
->closes
) {
3642 * We have a pending close on this channel,
3643 * which we decided on before the server acked
3644 * the channel open. So now we know the
3645 * remoteid, we can close it again.
3647 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
3648 PKT_INT
, c
->remoteid
, PKT_END
);
3652 static void ssh1_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
3654 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
3655 struct ssh_channel
*c
;
3657 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
3658 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3659 logevent("Forwarded connection refused by server");
3660 pfd_close(c
->u
.pfd
.s
);
3661 del234(ssh
->channels
, c
);
3666 static void ssh1_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
3668 /* Remote side closes a channel. */
3669 unsigned i
= ssh_pkt_getuint32(pktin
);
3670 struct ssh_channel
*c
;
3671 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
3672 if (c
&& ((int)c
->remoteid
) != -1) {
3675 (pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
3677 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
3678 logevent("Forwarded X11 connection terminated");
3679 assert(c
->u
.x11
.s
!= NULL
);
3680 x11_close(c
->u
.x11
.s
);
3683 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
3684 logevent("Forwarded port closed");
3685 assert(c
->u
.pfd
.s
!= NULL
);
3686 pfd_close(c
->u
.pfd
.s
);
3690 c
->closes
|= (closetype
<< 2); /* seen this message */
3691 if (!(c
->closes
& closetype
)) {
3692 send_packet(ssh
, pktin
->type
, PKT_INT
, c
->remoteid
,
3694 c
->closes
|= closetype
; /* sent it too */
3697 if (c
->closes
== 15) {
3698 del234(ssh
->channels
, c
);
3702 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
3703 pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
3704 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
3709 static void ssh1_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
3711 /* Data sent down one of our channels. */
3712 int i
= ssh_pkt_getuint32(pktin
);
3715 struct ssh_channel
*c
;
3717 ssh_pkt_getstring(pktin
, &p
, &len
);
3719 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
3724 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
3727 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
3730 /* Data for an agent message. Buffer it. */
3732 if (c
->u
.a
.lensofar
< 4) {
3733 int l
= min(4 - c
->u
.a
.lensofar
, len
);
3734 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
3738 c
->u
.a
.lensofar
+= l
;
3740 if (c
->u
.a
.lensofar
== 4) {
3742 4 + GET_32BIT(c
->u
.a
.msglen
);
3743 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
3745 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
3747 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
3749 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
3751 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
3755 c
->u
.a
.lensofar
+= l
;
3757 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
3760 if (agent_query(c
->u
.a
.message
,
3763 ssh_agentf_callback
, c
))
3764 ssh_agentf_callback(c
, reply
, replylen
);
3765 sfree(c
->u
.a
.message
);
3766 c
->u
.a
.lensofar
= 0;
3769 bufsize
= 0; /* agent channels never back up */
3772 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3773 c
->v
.v1
.throttling
= 1;
3774 ssh1_throttle(ssh
, +1);
3779 static void ssh1_smsg_exit_status(Ssh ssh
, struct Packet
*pktin
)
3782 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
3783 sprintf(buf
, "Server sent command exit status %d",
3786 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
3788 * In case `helpful' firewalls or proxies tack
3789 * extra human-readable text on the end of the
3790 * session which we might mistake for another
3791 * encrypted packet, we close the session once
3792 * we've sent EXIT_CONFIRMATION.
3794 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3797 static void do_ssh1_connection(Ssh ssh
, unsigned char *in
, int inlen
,
3798 struct Packet
*pktin
)
3800 crBegin(ssh
->do_ssh1_connection_crstate
);
3802 ssh
->packet_dispatch
[SSH1_SMSG_STDOUT_DATA
] =
3803 ssh
->packet_dispatch
[SSH1_SMSG_STDERR_DATA
] =
3804 ssh1_smsg_stdout_stderr_data
;
3806 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
] =
3807 ssh1_msg_channel_open_confirmation
;
3808 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_FAILURE
] =
3809 ssh1_msg_channel_open_failure
;
3810 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE
] =
3811 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
] =
3812 ssh1_msg_channel_close
;
3813 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_DATA
] = ssh1_msg_channel_data
;
3814 ssh
->packet_dispatch
[SSH1_SMSG_EXIT_STATUS
] = ssh1_smsg_exit_status
;
3816 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
3817 logevent("Requesting agent forwarding");
3818 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
3822 if (pktin
->type
!= SSH1_SMSG_SUCCESS
3823 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
3824 bombout(("Protocol confusion"));
3826 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3827 logevent("Agent forwarding refused");
3829 logevent("Agent forwarding enabled");
3830 ssh
->agentfwd_enabled
= TRUE
;
3831 ssh
->packet_dispatch
[SSH1_SMSG_AGENT_OPEN
] = ssh1_smsg_agent_open
;
3835 if (ssh
->cfg
.x11_forward
) {
3836 char proto
[20], data
[64];
3837 logevent("Requesting X11 forwarding");
3838 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
3839 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
3840 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
3841 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
3842 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
3843 PKT_STR
, proto
, PKT_STR
, data
,
3844 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
3847 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
3848 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
3853 if (pktin
->type
!= SSH1_SMSG_SUCCESS
3854 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
3855 bombout(("Protocol confusion"));
3857 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3858 logevent("X11 forwarding refused");
3860 logevent("X11 forwarding enabled");
3861 ssh
->X11_fwd_enabled
= TRUE
;
3862 ssh
->packet_dispatch
[SSH1_SMSG_X11_OPEN
] = ssh1_smsg_x11_open
;
3869 int sport
,dport
,sserv
,dserv
;
3870 char sports
[256], dports
[256], saddr
[256], host
[256];
3872 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3873 /* Add port forwardings. */
3874 ssh
->portfwd_strptr
= ssh
->cfg
.portfwd
;
3875 while (*ssh
->portfwd_strptr
) {
3876 type
= *ssh
->portfwd_strptr
++;
3879 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= '\t') {
3880 if (*ssh
->portfwd_strptr
== ':') {
3882 * We've seen a colon in the middle of the
3883 * source port number. This means that
3884 * everything we've seen until now is the
3885 * source _address_, so we'll move it into
3886 * saddr and start sports from the beginning
3889 ssh
->portfwd_strptr
++;
3891 strcpy(saddr
, sports
);
3894 if (n
< 255) sports
[n
++] = *ssh
->portfwd_strptr
++;
3898 if (*ssh
->portfwd_strptr
== '\t')
3899 ssh
->portfwd_strptr
++;
3901 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= ':') {
3902 if (n
< 255) host
[n
++] = *ssh
->portfwd_strptr
++;
3905 if (*ssh
->portfwd_strptr
== ':')
3906 ssh
->portfwd_strptr
++;
3908 while (*ssh
->portfwd_strptr
) {
3909 if (n
< 255) dports
[n
++] = *ssh
->portfwd_strptr
++;
3912 ssh
->portfwd_strptr
++;
3913 dport
= atoi(dports
);
3917 dport
= net_service_lookup(dports
);
3919 logeventf(ssh
, "Service lookup failed for"
3920 " destination port \"%s\"", dports
);
3924 while (*ssh
->portfwd_strptr
) ssh
->portfwd_strptr
++;
3926 ssh
->portfwd_strptr
++; /* eat the NUL and move to next one */
3928 sport
= atoi(sports
);
3932 sport
= net_service_lookup(sports
);
3934 logeventf(ssh
, "Service lookup failed for source"
3935 " port \"%s\"", sports
);
3938 if (sport
&& dport
) {
3939 /* Set up a description of the source port. */
3940 static char *sportdesc
;
3941 sportdesc
= dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
3942 (int)(*saddr?
strlen(saddr
):0), *saddr?saddr
:NULL
,
3943 (int)(*saddr?
1:0), ":",
3944 (int)(sserv ?
strlen(sports
) : 0), sports
,
3945 sserv
, "(", sport
, sserv
, ")");
3947 /* Verbose description of the destination port */
3948 char *dportdesc
= dupprintf("%s:%.*s%.*s%d%.*s",
3950 (int)(dserv ?
strlen(dports
) : 0), dports
,
3951 dserv
, "(", dport
, dserv
, ")");
3952 const char *err
= pfd_addforward(host
, dport
,
3953 *saddr ? saddr
: NULL
,
3954 sport
, ssh
, &ssh
->cfg
);
3956 logeventf(ssh
, "Local port %s forward to %s"
3957 " failed: %s", sportdesc
, dportdesc
, err
);
3959 logeventf(ssh
, "Local port %s forwarding to %s",
3960 sportdesc
, dportdesc
);
3963 } else if (type
== 'D') {
3964 const char *err
= pfd_addforward(NULL
, -1,
3965 *saddr ? saddr
: NULL
,
3966 sport
, ssh
, &ssh
->cfg
);
3968 logeventf(ssh
, "Local port %s SOCKS dynamic forward"
3969 " setup failed: %s", sportdesc
, err
);
3971 logeventf(ssh
, "Local port %s doing SOCKS"
3972 " dynamic forwarding", sportdesc
);
3975 struct ssh_rportfwd
*pf
;
3976 pf
= snew(struct ssh_rportfwd
);
3977 strcpy(pf
->dhost
, host
);
3981 "SSH1 cannot handle source address spec \"%s:%d\"; ignoring",
3984 if (add234(ssh
->rportfwds
, pf
) != pf
) {
3986 "Duplicate remote port forwarding to %s:%d",
3990 logeventf(ssh
, "Requesting remote port %.*s%.*s%d%.*s"
3991 " forward to %s:%.*s%.*s%d%.*s",
3992 (int)(sserv ?
strlen(sports
) : 0), sports
,
3993 sserv
, "(", sport
, sserv
, ")",
3995 (int)(dserv ?
strlen(dports
) : 0), dports
,
3996 dserv
, "(", dport
, dserv
, ")");
3997 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
4005 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4006 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4007 bombout(("Protocol confusion"));
4009 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4010 c_write_str(ssh
, "Server refused port"
4012 logevent("Server refused this port forwarding");
4014 logevent("Remote port forwarding enabled");
4015 ssh
->packet_dispatch
[SSH1_MSG_PORT_OPEN
] =
4025 if (!ssh
->cfg
.nopty
) {
4026 /* Unpick the terminal-speed string. */
4027 /* XXX perhaps we should allow no speeds to be sent. */
4028 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
4029 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
4030 /* Send the pty request. */
4031 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
4032 PKT_STR
, ssh
->cfg
.termtype
,
4033 PKT_INT
, ssh
->term_height
,
4034 PKT_INT
, ssh
->term_width
,
4035 PKT_INT
, 0, PKT_INT
, 0, /* width,height in pixels */
4036 PKT_CHAR
, 192, PKT_INT
, ssh
->ispeed
, /* TTY_OP_ISPEED */
4037 PKT_CHAR
, 193, PKT_INT
, ssh
->ospeed
, /* TTY_OP_OSPEED */
4038 PKT_CHAR
, 0, PKT_END
);
4039 ssh
->state
= SSH_STATE_INTERMED
;
4043 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4044 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4045 bombout(("Protocol confusion"));
4047 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4048 c_write_str(ssh
, "Server refused to allocate pty\r\n");
4049 ssh
->editing
= ssh
->echoing
= 1;
4051 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
4052 ssh
->ospeed
, ssh
->ispeed
);
4054 ssh
->editing
= ssh
->echoing
= 1;
4057 if (ssh
->cfg
.compression
) {
4058 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
4062 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4063 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4064 bombout(("Protocol confusion"));
4066 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4067 c_write_str(ssh
, "Server refused to compress\r\n");
4069 logevent("Started compression");
4070 ssh
->v1_compressing
= TRUE
;
4071 ssh
->cs_comp_ctx
= zlib_compress_init();
4072 logevent("Initialised zlib (RFC1950) compression");
4073 ssh
->sc_comp_ctx
= zlib_decompress_init();
4074 logevent("Initialised zlib (RFC1950) decompression");
4078 * Start the shell or command.
4080 * Special case: if the first-choice command is an SSH2
4081 * subsystem (hence not usable here) and the second choice
4082 * exists, we fall straight back to that.
4085 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
4087 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
4088 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
4089 ssh
->fallback_cmd
= TRUE
;
4092 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
4094 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
4095 logevent("Started session");
4098 ssh
->state
= SSH_STATE_SESSION
;
4099 if (ssh
->size_needed
)
4100 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
4101 if (ssh
->eof_needed
)
4102 ssh_special(ssh
, TS_EOF
);
4105 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
4107 ssh
->channels
= newtree234(ssh_channelcmp
);
4111 * By this point, most incoming packets are already being
4112 * handled by the dispatch table, and we need only pay
4113 * attention to the unusual ones.
4118 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
4119 /* may be from EXEC_SHELL on some servers */
4120 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4121 /* may be from EXEC_SHELL on some servers
4122 * if no pty is available or in other odd cases. Ignore */
4124 bombout(("Strange packet received: type %d", pktin
->type
));
4129 int len
= min(inlen
, 512);
4130 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4131 PKT_INT
, len
, PKT_DATA
, in
, len
,
4132 PKTT_OTHER
, PKT_END
);
4143 * Handle the top-level SSH2 protocol.
4145 static void ssh1_msg_debug(Ssh ssh
, struct Packet
*pktin
)
4150 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4151 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
4156 static void ssh1_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
4158 /* log reason code in disconnect message */
4162 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4163 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen
, msg
));
4166 void ssh_msg_ignore(Ssh ssh
, struct Packet
*pktin
)
4168 /* Do nothing, because we're ignoring it! Duhh. */
4171 static void ssh1_protocol_setup(Ssh ssh
)
4176 * Most messages are handled by the coroutines.
4178 for (i
= 0; i
< 256; i
++)
4179 ssh
->packet_dispatch
[i
] = NULL
;
4182 * These special message types we install handlers for.
4184 ssh
->packet_dispatch
[SSH1_MSG_DISCONNECT
] = ssh1_msg_disconnect
;
4185 ssh
->packet_dispatch
[SSH1_MSG_IGNORE
] = ssh_msg_ignore
;
4186 ssh
->packet_dispatch
[SSH1_MSG_DEBUG
] = ssh1_msg_debug
;
4189 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
4190 struct Packet
*pktin
)
4192 if (ssh
->state
== SSH_STATE_CLOSED
)
4195 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
4196 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
4200 if (!ssh
->protocol_initial_phase_done
) {
4201 if (do_ssh1_login(ssh
, in
, inlen
, pktin
))
4202 ssh
->protocol_initial_phase_done
= TRUE
;
4207 do_ssh1_connection(ssh
, in
, inlen
, pktin
);
4211 * Utility routine for decoding comma-separated strings in KEXINIT.
4213 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
4216 if (!needle
|| !haystack
) /* protect against null pointers */
4218 needlen
= strlen(needle
);
4221 * Is it at the start of the string?
4223 if (haylen
>= needlen
&& /* haystack is long enough */
4224 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4225 (haylen
== needlen
|| haystack
[needlen
] == ',')
4226 /* either , or EOS follows */
4230 * If not, search for the next comma and resume after that.
4231 * If no comma found, terminate.
4233 while (haylen
> 0 && *haystack
!= ',')
4234 haylen
--, haystack
++;
4237 haylen
--, haystack
++; /* skip over comma itself */
4242 * SSH2 key creation method.
4244 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
4245 unsigned char *sessid
, char chr
,
4246 unsigned char *keyspace
)
4249 /* First 20 bytes. */
4251 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4253 SHA_Bytes(&s
, H
, 20);
4254 SHA_Bytes(&s
, &chr
, 1);
4255 SHA_Bytes(&s
, sessid
, 20);
4256 SHA_Final(&s
, keyspace
);
4257 /* Next 20 bytes. */
4259 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4261 SHA_Bytes(&s
, H
, 20);
4262 SHA_Bytes(&s
, keyspace
, 20);
4263 SHA_Final(&s
, keyspace
+ 20);
4267 * Handle the SSH2 transport layer.
4269 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
,
4270 struct Packet
*pktin
)
4272 struct do_ssh2_transport_state
{
4273 int nbits
, pbits
, warn
;
4274 Bignum p
, g
, e
, f
, K
;
4275 int kex_init_value
, kex_reply_value
;
4276 const struct ssh_mac
**maclist
;
4278 const struct ssh2_cipher
*cscipher_tobe
;
4279 const struct ssh2_cipher
*sccipher_tobe
;
4280 const struct ssh_mac
*csmac_tobe
;
4281 const struct ssh_mac
*scmac_tobe
;
4282 const struct ssh_compress
*cscomp_tobe
;
4283 const struct ssh_compress
*sccomp_tobe
;
4284 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4285 int hostkeylen
, siglen
;
4286 void *hkey
; /* actual host key */
4287 unsigned char exchange_hash
[20];
4288 int n_preferred_ciphers
;
4289 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
4290 const struct ssh_compress
*preferred_comp
;
4292 struct Packet
*pktout
;
4294 crState(do_ssh2_transport_state
);
4296 crBegin(ssh
->do_ssh2_transport_crstate
);
4298 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
4299 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
4300 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
4308 * Set up the preferred ciphers. (NULL => warn below here)
4310 s
->n_preferred_ciphers
= 0;
4311 for (i
= 0; i
< CIPHER_MAX
; i
++) {
4312 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
4313 case CIPHER_BLOWFISH
:
4314 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
4317 if (ssh
->cfg
.ssh2_des_cbc
) {
4318 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
4322 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
4325 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
4328 /* Flag for later. Don't bother if it's the last in
4330 if (i
< CIPHER_MAX
- 1) {
4331 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
4339 * Set up preferred compression.
4341 if (ssh
->cfg
.compression
)
4342 s
->preferred_comp
= &ssh_zlib
;
4344 s
->preferred_comp
= &ssh_comp_none
;
4347 * Be prepared to work around the buggy MAC problem.
4349 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
4350 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
4352 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
4356 int i
, j
, cipherstr_started
;
4359 * Enable queueing of outgoing auth- or connection-layer
4360 * packets while we are in the middle of a key exchange.
4362 ssh
->queueing
= TRUE
;
4365 * Flag that KEX is in progress.
4367 ssh
->kex_in_progress
= TRUE
;
4370 * Construct and send our key exchange packet.
4372 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEXINIT
);
4373 for (i
= 0; i
< 16; i
++)
4374 ssh2_pkt_addbyte(s
->pktout
, (unsigned char) random_byte());
4375 /* List key exchange algorithms. */
4376 ssh2_pkt_addstring_start(s
->pktout
);
4377 for (i
= 0; i
< lenof(kex_algs
); i
++) {
4378 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
4379 (ssh
->remote_bugs
& BUG_SSH2_DH_GEX
))
4381 ssh2_pkt_addstring_str(s
->pktout
, kex_algs
[i
]->name
);
4382 if (i
< lenof(kex_algs
) - 1)
4383 ssh2_pkt_addstring_str(s
->pktout
, ",");
4385 /* List server host key algorithms. */
4386 ssh2_pkt_addstring_start(s
->pktout
);
4387 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4388 ssh2_pkt_addstring_str(s
->pktout
, hostkey_algs
[i
]->name
);
4389 if (i
< lenof(hostkey_algs
) - 1)
4390 ssh2_pkt_addstring_str(s
->pktout
, ",");
4392 /* List client->server encryption algorithms. */
4393 ssh2_pkt_addstring_start(s
->pktout
);
4394 cipherstr_started
= 0;
4395 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4396 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4397 if (!c
) continue; /* warning flag */
4398 for (j
= 0; j
< c
->nciphers
; j
++) {
4399 if (cipherstr_started
)
4400 ssh2_pkt_addstring_str(s
->pktout
, ",");
4401 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4402 cipherstr_started
= 1;
4405 /* List server->client encryption algorithms. */
4406 ssh2_pkt_addstring_start(s
->pktout
);
4407 cipherstr_started
= 0;
4408 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4409 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4410 if (!c
) continue; /* warning flag */
4411 for (j
= 0; j
< c
->nciphers
; j
++) {
4412 if (cipherstr_started
)
4413 ssh2_pkt_addstring_str(s
->pktout
, ",");
4414 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4415 cipherstr_started
= 1;
4418 /* List client->server MAC algorithms. */
4419 ssh2_pkt_addstring_start(s
->pktout
);
4420 for (i
= 0; i
< s
->nmacs
; i
++) {
4421 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4422 if (i
< s
->nmacs
- 1)
4423 ssh2_pkt_addstring_str(s
->pktout
, ",");
4425 /* List server->client MAC algorithms. */
4426 ssh2_pkt_addstring_start(s
->pktout
);
4427 for (i
= 0; i
< s
->nmacs
; i
++) {
4428 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4429 if (i
< s
->nmacs
- 1)
4430 ssh2_pkt_addstring_str(s
->pktout
, ",");
4432 /* List client->server compression algorithms. */
4433 ssh2_pkt_addstring_start(s
->pktout
);
4434 assert(lenof(compressions
) > 1);
4435 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4436 for (i
= 0; i
< lenof(compressions
); i
++) {
4437 const struct ssh_compress
*c
= compressions
[i
];
4438 if (c
!= s
->preferred_comp
) {
4439 ssh2_pkt_addstring_str(s
->pktout
, ",");
4440 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4443 /* List server->client compression algorithms. */
4444 ssh2_pkt_addstring_start(s
->pktout
);
4445 assert(lenof(compressions
) > 1);
4446 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4447 for (i
= 0; i
< lenof(compressions
); i
++) {
4448 const struct ssh_compress
*c
= compressions
[i
];
4449 if (c
!= s
->preferred_comp
) {
4450 ssh2_pkt_addstring_str(s
->pktout
, ",");
4451 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4454 /* List client->server languages. Empty list. */
4455 ssh2_pkt_addstring_start(s
->pktout
);
4456 /* List server->client languages. Empty list. */
4457 ssh2_pkt_addstring_start(s
->pktout
);
4458 /* First KEX packet does _not_ follow, because we're not that brave. */
4459 ssh2_pkt_addbool(s
->pktout
, FALSE
);
4461 ssh2_pkt_adduint32(s
->pktout
, 0);
4464 ssh
->exhash
= ssh
->exhashbase
;
4465 sha_string(&ssh
->exhash
, s
->pktout
->data
+ 5, s
->pktout
->length
- 5);
4467 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
4471 if (pktin
->length
> 5)
4472 sha_string(&ssh
->exhash
, pktin
->data
+ 5, pktin
->length
- 5);
4475 * Now examine the other side's KEXINIT to see what we're up
4482 if (pktin
->type
!= SSH2_MSG_KEXINIT
) {
4483 bombout(("expected key exchange packet from server"));
4487 ssh
->hostkey
= NULL
;
4488 s
->cscipher_tobe
= NULL
;
4489 s
->sccipher_tobe
= NULL
;
4490 s
->csmac_tobe
= NULL
;
4491 s
->scmac_tobe
= NULL
;
4492 s
->cscomp_tobe
= NULL
;
4493 s
->sccomp_tobe
= NULL
;
4494 pktin
->savedpos
+= 16; /* skip garbage cookie */
4495 ssh_pkt_getstring(pktin
, &str
, &len
); /* key exchange algorithms */
4496 for (i
= 0; i
< lenof(kex_algs
); i
++) {
4497 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
4498 (ssh
->remote_bugs
& BUG_SSH2_DH_GEX
))
4500 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
4501 ssh
->kex
= kex_algs
[i
];
4505 ssh_pkt_getstring(pktin
, &str
, &len
); /* host key algorithms */
4506 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4507 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
4508 ssh
->hostkey
= hostkey_algs
[i
];
4512 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server cipher */
4514 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4515 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4519 for (j
= 0; j
< c
->nciphers
; j
++) {
4520 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4521 s
->cscipher_tobe
= c
->list
[j
];
4526 if (s
->cscipher_tobe
) {
4528 askcipher(ssh
->frontend
, s
->cscipher_tobe
->name
, 1);
4532 if (!s
->cscipher_tobe
) {
4533 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
4534 str ? str
: "(null)"));
4538 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client cipher */
4540 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4541 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4545 for (j
= 0; j
< c
->nciphers
; j
++) {
4546 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4547 s
->sccipher_tobe
= c
->list
[j
];
4552 if (s
->sccipher_tobe
) {
4554 askcipher(ssh
->frontend
, s
->sccipher_tobe
->name
, 2);
4558 if (!s
->sccipher_tobe
) {
4559 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
4560 str ? str
: "(null)"));
4564 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server mac */
4565 for (i
= 0; i
< s
->nmacs
; i
++) {
4566 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4567 s
->csmac_tobe
= s
->maclist
[i
];
4571 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client mac */
4572 for (i
= 0; i
< s
->nmacs
; i
++) {
4573 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4574 s
->scmac_tobe
= s
->maclist
[i
];
4578 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server compression */
4579 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4580 const struct ssh_compress
*c
=
4581 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4582 if (in_commasep_string(c
->name
, str
, len
)) {
4587 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client compression */
4588 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4589 const struct ssh_compress
*c
=
4590 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4591 if (in_commasep_string(c
->name
, str
, len
)) {
4599 * Work out the number of bits of key we will need from the key
4600 * exchange. We start with the maximum key length of either
4606 csbits
= s
->cscipher_tobe
->keylen
;
4607 scbits
= s
->sccipher_tobe
->keylen
;
4608 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
4610 /* The keys only have 160-bit entropy, since they're based on
4611 * a SHA-1 hash. So cap the key size at 160 bits. */
4616 * If we're doing Diffie-Hellman group exchange, start by
4617 * requesting a group.
4619 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4620 logevent("Doing Diffie-Hellman group exchange");
4621 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
4623 * Work out how big a DH group we will need to allow that
4626 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
4627 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
4628 ssh2_pkt_adduint32(s
->pktout
, s
->pbits
);
4629 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
4632 if (pktin
->type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
4633 bombout(("expected key exchange group packet from server"));
4636 s
->p
= ssh2_pkt_getmp(pktin
);
4637 s
->g
= ssh2_pkt_getmp(pktin
);
4638 if (!s
->p
|| !s
->g
) {
4639 bombout(("unable to read mp-ints from incoming group packet"));
4642 ssh
->kex_ctx
= dh_setup_group(s
->p
, s
->g
);
4643 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
4644 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
4646 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP1
;
4647 ssh
->kex_ctx
= dh_setup_group1();
4648 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
4649 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
4652 logevent("Doing Diffie-Hellman key exchange");
4654 * Now generate and send e for Diffie-Hellman.
4656 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
4657 s
->pktout
= ssh2_pkt_init(s
->kex_init_value
);
4658 ssh2_pkt_addmp(s
->pktout
, s
->e
);
4659 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
4662 if (pktin
->type
!= s
->kex_reply_value
) {
4663 bombout(("expected key exchange reply packet from server"));
4666 ssh_pkt_getstring(pktin
, &s
->hostkeydata
, &s
->hostkeylen
);
4667 s
->f
= ssh2_pkt_getmp(pktin
);
4669 bombout(("unable to parse key exchange reply packet"));
4672 ssh_pkt_getstring(pktin
, &s
->sigdata
, &s
->siglen
);
4674 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
4676 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
4677 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4678 sha_uint32(&ssh
->exhash
, s
->pbits
);
4679 sha_mpint(&ssh
->exhash
, s
->p
);
4680 sha_mpint(&ssh
->exhash
, s
->g
);
4682 sha_mpint(&ssh
->exhash
, s
->e
);
4683 sha_mpint(&ssh
->exhash
, s
->f
);
4684 sha_mpint(&ssh
->exhash
, s
->K
);
4685 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
4687 dh_cleanup(ssh
->kex_ctx
);
4688 ssh
->kex_ctx
= NULL
;
4691 debug(("Exchange hash is:\n"));
4692 dmemdump(s
->exchange_hash
, 20);
4695 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
4697 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
4698 (char *)s
->exchange_hash
, 20)) {
4699 bombout(("Server's host key did not match the signature supplied"));
4704 * Authenticate remote host: verify host key. (We've already
4705 * checked the signature of the exchange hash.)
4707 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
4708 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
4709 verify_ssh_host_key(ssh
->frontend
,
4710 ssh
->savedhost
, ssh
->savedport
, ssh
->hostkey
->keytype
,
4711 s
->keystr
, s
->fingerprint
);
4712 if (s
->first_kex
) { /* don't bother logging this in rekeys */
4713 logevent("Host key fingerprint is:");
4714 logevent(s
->fingerprint
);
4716 sfree(s
->fingerprint
);
4718 ssh
->hostkey
->freekey(s
->hkey
);
4721 * The exchange hash from the very first key exchange is also
4722 * the session id, used in session key construction and
4726 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
4727 sizeof(s
->exchange_hash
));
4730 * Send SSH2_MSG_NEWKEYS.
4732 s
->pktout
= ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
4733 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
4734 ssh
->outgoing_data_size
= 0; /* start counting from here */
4737 * We've sent client NEWKEYS, so create and initialise
4738 * client-to-servere session keys.
4740 if (ssh
->cs_cipher_ctx
)
4741 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
4742 ssh
->cscipher
= s
->cscipher_tobe
;
4743 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
4745 if (ssh
->cs_mac_ctx
)
4746 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
4747 ssh
->csmac
= s
->csmac_tobe
;
4748 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
4750 if (ssh
->cs_comp_ctx
)
4751 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
4752 ssh
->cscomp
= s
->cscomp_tobe
;
4753 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
4756 * Set IVs on client-to-server keys. Here we use the exchange
4757 * hash from the _first_ key exchange.
4760 unsigned char keyspace
[40];
4761 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
4762 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
4763 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
4764 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
4765 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
4766 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
4769 logeventf(ssh
, "Initialised %.200s client->server encryption",
4770 ssh
->cscipher
->text_name
);
4771 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
4772 ssh
->csmac
->text_name
);
4773 if (ssh
->cscomp
->text_name
)
4774 logeventf(ssh
, "Initialised %s compression",
4775 ssh
->cscomp
->text_name
);
4778 * Now our end of the key exchange is complete, we can send all
4779 * our queued higher-layer packets.
4781 ssh
->queueing
= FALSE
;
4782 ssh2_pkt_queuesend(ssh
);
4785 * Expect SSH2_MSG_NEWKEYS from server.
4788 if (pktin
->type
!= SSH2_MSG_NEWKEYS
) {
4789 bombout(("expected new-keys packet from server"));
4792 ssh
->incoming_data_size
= 0; /* start counting from here */
4795 * We've seen server NEWKEYS, so create and initialise
4796 * server-to-client session keys.
4798 if (ssh
->sc_cipher_ctx
)
4799 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
4800 ssh
->sccipher
= s
->sccipher_tobe
;
4801 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
4803 if (ssh
->sc_mac_ctx
)
4804 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
4805 ssh
->scmac
= s
->scmac_tobe
;
4806 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
4808 if (ssh
->sc_comp_ctx
)
4809 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
4810 ssh
->sccomp
= s
->sccomp_tobe
;
4811 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
4814 * Set IVs on server-to-client keys. Here we use the exchange
4815 * hash from the _first_ key exchange.
4818 unsigned char keyspace
[40];
4819 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
4820 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
4821 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
4822 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
4823 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
4824 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
4826 logeventf(ssh
, "Initialised %.200s server->client encryption",
4827 ssh
->sccipher
->text_name
);
4828 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
4829 ssh
->scmac
->text_name
);
4830 if (ssh
->sccomp
->text_name
)
4831 logeventf(ssh
, "Initialised %s decompression",
4832 ssh
->sccomp
->text_name
);
4835 * Free key exchange data.
4839 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4845 * Key exchange is over. Schedule a timer for our next rekey.
4847 ssh
->kex_in_progress
= FALSE
;
4848 ssh
->next_rekey
= schedule_timer(REKEY_TIMEOUT
, ssh2_timer
, ssh
);
4851 * If this is the first key exchange phase, we must pass the
4852 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
4853 * wants to see it but because it will need time to initialise
4854 * itself before it sees an actual packet. In subsequent key
4855 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
4856 * it would only confuse the layer above.
4858 if (!s
->first_kex
) {
4864 * Now we're encrypting. Begin returning 1 to the protocol main
4865 * function so that other things can run on top of the
4866 * transport. If we ever see a KEXINIT, we must go back to the
4869 * We _also_ go back to the start if we see pktin==NULL and
4870 * inlen==-1, because this is a special signal meaning
4871 * `initiate client-driven rekey', and `in' contains a message
4872 * giving the reason for the rekey.
4874 while (!((pktin
&& pktin
->type
== SSH2_MSG_KEXINIT
) ||
4875 (!pktin
&& inlen
== -1))) {
4879 logevent("Server initiated key re-exchange");
4881 logevent((char *)in
);
4883 goto begin_key_exchange
;
4889 * Add data to an SSH2 channel output buffer.
4891 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
4894 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
4898 * Attempt to send data on an SSH2 channel.
4900 static int ssh2_try_send(struct ssh_channel
*c
)
4903 struct Packet
*pktout
;
4905 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
4908 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
4909 if ((unsigned)len
> c
->v
.v2
.remwindow
)
4910 len
= c
->v
.v2
.remwindow
;
4911 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
4912 len
= c
->v
.v2
.remmaxpkt
;
4913 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
4914 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
4915 dont_log_data(ssh
, pktout
, PKTLOG_OMIT
);
4916 ssh2_pkt_addstring_start(pktout
);
4917 ssh2_pkt_addstring_data(pktout
, data
, len
);
4918 end_log_omission(ssh
, pktout
);
4919 ssh2_pkt_send(ssh
, pktout
);
4920 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
4921 c
->v
.v2
.remwindow
-= len
;
4925 * After having sent as much data as we can, return the amount
4928 return bufchain_size(&c
->v
.v2
.outbuffer
);
4932 * Potentially enlarge the window on an SSH2 channel.
4934 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
4939 * Never send WINDOW_ADJUST for a channel that the remote side
4940 * already thinks it's closed; there's no point, since it won't
4941 * be sending any more data anyway.
4946 if (newwin
> c
->v
.v2
.locwindow
) {
4947 struct Packet
*pktout
;
4949 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4950 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
4951 ssh2_pkt_adduint32(pktout
, newwin
- c
->v
.v2
.locwindow
);
4952 ssh2_pkt_send(ssh
, pktout
);
4953 c
->v
.v2
.locwindow
= newwin
;
4957 static void ssh2_msg_channel_window_adjust(Ssh ssh
, struct Packet
*pktin
)
4959 unsigned i
= ssh_pkt_getuint32(pktin
);
4960 struct ssh_channel
*c
;
4961 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4962 if (c
&& !c
->closes
)
4963 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
4966 static void ssh2_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
4970 unsigned i
= ssh_pkt_getuint32(pktin
);
4971 struct ssh_channel
*c
;
4972 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4974 return; /* nonexistent channel */
4975 if (pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
4976 ssh_pkt_getuint32(pktin
) != SSH2_EXTENDED_DATA_STDERR
)
4977 return; /* extended but not stderr */
4978 ssh_pkt_getstring(pktin
, &data
, &length
);
4981 c
->v
.v2
.locwindow
-= length
;
4983 case CHAN_MAINSESSION
:
4985 from_backend(ssh
->frontend
, pktin
->type
==
4986 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
4990 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
4993 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
4996 while (length
> 0) {
4997 if (c
->u
.a
.lensofar
< 4) {
4998 int l
= min(4 - c
->u
.a
.lensofar
, length
);
4999 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5003 c
->u
.a
.lensofar
+= l
;
5005 if (c
->u
.a
.lensofar
== 4) {
5007 4 + GET_32BIT(c
->u
.a
.msglen
);
5008 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
5010 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5012 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5014 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5016 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5020 c
->u
.a
.lensofar
+= l
;
5022 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5025 if (agent_query(c
->u
.a
.message
,
5028 ssh_agentf_callback
, c
))
5029 ssh_agentf_callback(c
, reply
, replylen
);
5030 sfree(c
->u
.a
.message
);
5031 c
->u
.a
.lensofar
= 0;
5038 * If we are not buffering too much data,
5039 * enlarge the window again at the remote side.
5041 if (bufsize
< OUR_V2_WINSIZE
)
5042 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5046 static void ssh2_msg_channel_eof(Ssh ssh
, struct Packet
*pktin
)
5048 unsigned i
= ssh_pkt_getuint32(pktin
);
5049 struct ssh_channel
*c
;
5051 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5053 return; /* nonexistent channel */
5055 if (c
->type
== CHAN_X11
) {
5057 * Remote EOF on an X11 channel means we should
5058 * wrap up and close the channel ourselves.
5060 x11_close(c
->u
.x11
.s
);
5062 } else if (c
->type
== CHAN_AGENT
) {
5064 } else if (c
->type
== CHAN_SOCKDATA
) {
5065 pfd_close(c
->u
.pfd
.s
);
5070 static void ssh2_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
5072 unsigned i
= ssh_pkt_getuint32(pktin
);
5073 struct ssh_channel
*c
;
5074 struct Packet
*pktout
;
5076 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5077 if (!c
|| ((int)c
->remoteid
) == -1) {
5078 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5079 c ?
"half-open" : "nonexistent", i
));
5082 /* Do pre-close processing on the channel. */
5084 case CHAN_MAINSESSION
:
5085 ssh
->mainchan
= NULL
;
5086 update_specials_menu(ssh
->frontend
);
5089 if (c
->u
.x11
.s
!= NULL
)
5090 x11_close(c
->u
.x11
.s
);
5097 if (c
->u
.pfd
.s
!= NULL
)
5098 pfd_close(c
->u
.pfd
.s
);
5102 if (c
->closes
== 0) {
5103 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5104 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5105 ssh2_pkt_send(ssh
, pktout
);
5107 del234(ssh
->channels
, c
);
5108 bufchain_clear(&c
->v
.v2
.outbuffer
);
5112 * See if that was the last channel left open.
5113 * (This is only our termination condition if we're
5114 * not running in -N mode.)
5116 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
5117 logevent("All channels closed. Disconnecting");
5120 * We used to send SSH_MSG_DISCONNECT here,
5121 * because I'd believed that _every_ conforming
5122 * SSH2 connection had to end with a disconnect
5123 * being sent by at least one side; apparently
5124 * I was wrong and it's perfectly OK to
5125 * unceremoniously slam the connection shut
5126 * when you're done, and indeed OpenSSH feels
5127 * this is more polite than sending a
5128 * DISCONNECT. So now we don't.
5130 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5131 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5132 ssh2_pkt_addstring(s
->pktout
, "All open channels closed");
5133 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
5134 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5136 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5140 static void ssh2_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
5142 unsigned i
= ssh_pkt_getuint32(pktin
);
5143 struct ssh_channel
*c
;
5144 struct Packet
*pktout
;
5146 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5148 return; /* nonexistent channel */
5149 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5150 return; /* dunno why they're confirming this */
5151 c
->remoteid
= ssh_pkt_getuint32(pktin
);
5152 c
->type
= CHAN_SOCKDATA
;
5153 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
5154 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
5156 pfd_confirm(c
->u
.pfd
.s
);
5159 * We have a pending close on this channel,
5160 * which we decided on before the server acked
5161 * the channel open. So now we know the
5162 * remoteid, we can close it again.
5164 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5165 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5166 ssh2_pkt_send(ssh
, pktout
);
5170 static void ssh2_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
5172 static const char *const reasons
[] = {
5173 "<unknown reason code>",
5174 "Administratively prohibited",
5176 "Unknown channel type",
5177 "Resource shortage",
5179 unsigned i
= ssh_pkt_getuint32(pktin
);
5180 unsigned reason_code
;
5181 char *reason_string
;
5184 struct ssh_channel
*c
;
5185 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5187 return; /* nonexistent channel */
5188 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5189 return; /* dunno why they're failing this */
5191 reason_code
= ssh_pkt_getuint32(pktin
);
5192 if (reason_code
>= lenof(reasons
))
5193 reason_code
= 0; /* ensure reasons[reason_code] in range */
5194 ssh_pkt_getstring(pktin
, &reason_string
, &reason_length
);
5195 message
= dupprintf("Forwarded connection refused by"
5196 " server: %s [%.*s]", reasons
[reason_code
],
5197 reason_length
, reason_string
);
5201 pfd_close(c
->u
.pfd
.s
);
5203 del234(ssh
->channels
, c
);
5207 static void ssh2_msg_channel_request(Ssh ssh
, struct Packet
*pktin
)
5211 int typelen
, want_reply
;
5212 int reply
= SSH2_MSG_CHANNEL_FAILURE
; /* default */
5213 struct ssh_channel
*c
;
5214 struct Packet
*pktout
;
5216 localid
= ssh_pkt_getuint32(pktin
);
5217 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5218 want_reply
= ssh2_pkt_getbool(pktin
);
5221 * First, check that the channel exists. Otherwise,
5222 * we can instantly disconnect with a rude message.
5224 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
5227 sprintf(buf
, "Received channel request for nonexistent"
5228 " channel %d", localid
);
5230 pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5231 ssh2_pkt_adduint32(pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5232 ssh2_pkt_addstring(pktout
, buf
);
5233 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5234 ssh2_pkt_send_noqueue(ssh
, pktout
);
5235 connection_fatal(ssh
->frontend
, "%s", buf
);
5236 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5241 * Having got the channel number, we now look at
5242 * the request type string to see if it's something
5245 if (c
== ssh
->mainchan
) {
5247 * We recognise "exit-status" and "exit-signal" on
5248 * the primary channel.
5250 if (typelen
== 11 &&
5251 !memcmp(type
, "exit-status", 11)) {
5253 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
5254 logeventf(ssh
, "Server sent command exit status %d",
5256 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5258 } else if (typelen
== 11 &&
5259 !memcmp(type
, "exit-signal", 11)) {
5261 int is_plausible
= TRUE
, is_int
= FALSE
;
5262 char *fmt_sig
= "", *fmt_msg
= "";
5264 int msglen
= 0, core
= FALSE
;
5265 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
5266 * provide an `int' for the signal, despite its
5267 * having been a `string' in the drafts since at
5268 * least 2001. (Fixed in session.c 1.147.) Try to
5269 * infer which we can safely parse it as. */
5271 unsigned char *p
= pktin
->body
+
5273 long len
= pktin
->length
- pktin
->savedpos
;
5274 unsigned long num
= GET_32BIT(p
); /* what is it? */
5275 /* If it's 0, it hardly matters; assume string */
5279 int maybe_int
= FALSE
, maybe_str
= FALSE
;
5280 #define CHECK_HYPOTHESIS(offset, result) \
5283 if (q >= 0 && q+4 <= len) { \
5284 q = q + 4 + GET_32BIT(p+q); \
5285 if (q >= 0 && q+4 <= len && \
5286 (q = q + 4 + GET_32BIT(p+q)) && q == len) \
5290 CHECK_HYPOTHESIS(4+1, maybe_int
);
5291 CHECK_HYPOTHESIS(4+num
+1, maybe_str
);
5292 #undef CHECK_HYPOTHESIS
5293 if (maybe_int
&& !maybe_str
)
5295 else if (!maybe_int
&& maybe_str
)
5298 /* Crikey. Either or neither. Panic. */
5299 is_plausible
= FALSE
;
5304 /* Old non-standard OpenSSH. */
5305 int signum
= ssh_pkt_getuint32(pktin
);
5306 fmt_sig
= dupprintf(" %d", signum
);
5308 /* As per the drafts. */
5311 ssh_pkt_getstring(pktin
, &sig
, &siglen
);
5312 /* Signal name isn't supposed to be blank, but
5313 * let's cope gracefully if it is. */
5315 fmt_sig
= dupprintf(" \"%.*s\"",
5319 core
= ssh2_pkt_getbool(pktin
);
5320 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
5322 fmt_msg
= dupprintf(" (\"%.*s\")", msglen
, msg
);
5324 /* ignore lang tag */
5325 } /* else don't attempt to parse */
5326 logeventf(ssh
, "Server exited on signal%s%s%s",
5327 fmt_sig
, core ?
" (core dumped)" : "",
5329 if (*fmt_sig
) sfree(fmt_sig
);
5330 if (*fmt_msg
) sfree(fmt_msg
);
5331 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5336 * This is a channel request we don't know
5337 * about, so we now either ignore the request
5338 * or respond with CHANNEL_FAILURE, depending
5341 reply
= SSH2_MSG_CHANNEL_FAILURE
;
5344 pktout
= ssh2_pkt_init(reply
);
5345 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5346 ssh2_pkt_send(ssh
, pktout
);
5350 static void ssh2_msg_global_request(Ssh ssh
, struct Packet
*pktin
)
5353 int typelen
, want_reply
;
5354 struct Packet
*pktout
;
5356 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5357 want_reply
= ssh2_pkt_getbool(pktin
);
5360 * We currently don't support any global requests
5361 * at all, so we either ignore the request or
5362 * respond with REQUEST_FAILURE, depending on
5366 pktout
= ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
5367 ssh2_pkt_send(ssh
, pktout
);
5371 static void ssh2_msg_channel_open(Ssh ssh
, struct Packet
*pktin
)
5379 struct ssh_channel
*c
;
5380 unsigned remid
, winsize
, pktsize
;
5381 struct Packet
*pktout
;
5383 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5384 c
= snew(struct ssh_channel
);
5387 remid
= ssh_pkt_getuint32(pktin
);
5388 winsize
= ssh_pkt_getuint32(pktin
);
5389 pktsize
= ssh_pkt_getuint32(pktin
);
5391 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5394 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5395 addrstr
= snewn(peeraddrlen
+1, char);
5396 memcpy(addrstr
, peeraddr
, peeraddrlen
);
5397 addrstr
[peeraddrlen
] = '\0';
5398 peerport
= ssh_pkt_getuint32(pktin
);
5400 logeventf(ssh
, "Received X11 connect request from %s:%d",
5403 if (!ssh
->X11_fwd_enabled
)
5404 error
= "X11 forwarding is not enabled";
5405 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
5406 ssh
->x11auth
, addrstr
, peerport
,
5407 &ssh
->cfg
) != NULL
) {
5408 error
= "Unable to open an X11 connection";
5410 logevent("Opening X11 forward connection succeeded");
5415 } else if (typelen
== 15 &&
5416 !memcmp(type
, "forwarded-tcpip", 15)) {
5417 struct ssh_rportfwd pf
, *realpf
;
5420 ssh_pkt_getstring(pktin
, &dummy
, &dummylen
);/* skip address */
5421 pf
.sport
= ssh_pkt_getuint32(pktin
);
5422 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5423 peerport
= ssh_pkt_getuint32(pktin
);
5424 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
5425 logeventf(ssh
, "Received remote port %d open request "
5426 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
5427 if (realpf
== NULL
) {
5428 error
= "Remote port is not recognised";
5430 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
5434 logeventf(ssh
, "Attempting to forward remote port to "
5435 "%s:%d", realpf
->dhost
, realpf
->dport
);
5437 logeventf(ssh
, "Port open failed: %s", e
);
5438 error
= "Port open failed";
5440 logevent("Forwarded port opened successfully");
5441 c
->type
= CHAN_SOCKDATA
;
5444 } else if (typelen
== 22 &&
5445 !memcmp(type
, "auth-agent@openssh.com", 3)) {
5446 if (!ssh
->agentfwd_enabled
)
5447 error
= "Agent forwarding is not enabled";
5449 c
->type
= CHAN_AGENT
; /* identify channel type */
5450 c
->u
.a
.lensofar
= 0;
5453 error
= "Unsupported channel type requested";
5456 c
->remoteid
= remid
;
5458 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
5459 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5460 ssh2_pkt_adduint32(pktout
, SSH2_OPEN_CONNECT_FAILED
);
5461 ssh2_pkt_addstring(pktout
, error
);
5462 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5463 ssh2_pkt_send(ssh
, pktout
);
5464 logeventf(ssh
, "Rejected channel open: %s", error
);
5467 c
->localid
= alloc_channel_id(ssh
);
5469 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5470 c
->v
.v2
.remwindow
= winsize
;
5471 c
->v
.v2
.remmaxpkt
= pktsize
;
5472 bufchain_init(&c
->v
.v2
.outbuffer
);
5473 add234(ssh
->channels
, c
);
5474 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
5475 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5476 ssh2_pkt_adduint32(pktout
, c
->localid
);
5477 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);
5478 ssh2_pkt_adduint32(pktout
, 0x4000UL
); /* our max pkt size */
5479 ssh2_pkt_send(ssh
, pktout
);
5484 * Handle the SSH2 userauth and connection layers.
5486 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
5487 struct Packet
*pktin
)
5489 struct do_ssh2_authconn_state
{
5491 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
5493 AUTH_KEYBOARD_INTERACTIVE
5497 AUTH_TYPE_PUBLICKEY
,
5498 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
5499 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
5501 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
5502 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
5504 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
5505 int tried_pubkey_config
, tried_agent
, tried_keyb_inter
;
5506 int kbd_inter_running
;
5508 int num_prompts
, curr_prompt
, echo
;
5513 void *publickey_blob
;
5514 int publickey_bloblen
;
5515 unsigned char request
[5], *response
, *p
;
5519 char *pkblob
, *alg
, *commentp
;
5520 int pklen
, alglen
, commentlen
;
5521 int siglen
, retlen
, len
;
5522 char *q
, *agentreq
, *ret
;
5524 int num_env
, env_left
, env_ok
;
5525 struct Packet
*pktout
;
5527 crState(do_ssh2_authconn_state
);
5529 crBegin(ssh
->do_ssh2_authconn_crstate
);
5532 * Request userauth protocol, and await a response to it.
5534 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
5535 ssh2_pkt_addstring(s
->pktout
, "ssh-userauth");
5536 ssh2_pkt_send(ssh
, s
->pktout
);
5537 crWaitUntilV(pktin
);
5538 if (pktin
->type
!= SSH2_MSG_SERVICE_ACCEPT
) {
5539 bombout(("Server refused user authentication protocol"));
5544 * We repeat this whole loop, including the username prompt,
5545 * until we manage a successful authentication. If the user
5546 * types the wrong _password_, they can be sent back to the
5547 * beginning to try another username, if this is configured on.
5548 * (If they specify a username in the config, they are never
5549 * asked, even if they do give a wrong password.)
5551 * I think this best serves the needs of
5553 * - the people who have no configuration, no keys, and just
5554 * want to try repeated (username,password) pairs until they
5555 * type both correctly
5557 * - people who have keys and configuration but occasionally
5558 * need to fall back to passwords
5560 * - people with a key held in Pageant, who might not have
5561 * logged in to a particular machine before; so they want to
5562 * type a username, and then _either_ their key will be
5563 * accepted, _or_ they will type a password. If they mistype
5564 * the username they will want to be able to get back and
5567 s
->username
[0] = '\0';
5568 s
->got_username
= FALSE
;
5573 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
5575 * We got a username last time round this loop, and
5576 * with change_username turned off we don't try to get
5579 } else if (!*ssh
->cfg
.username
) {
5580 if (ssh_get_line
&& !ssh_getline_pw_only
) {
5581 if (!ssh_get_line("login as: ",
5582 s
->username
, sizeof(s
->username
), FALSE
)) {
5584 * get_line failed to get a username.
5587 logevent("No username provided. Abandoning session.");
5588 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5592 int ret
; /* need not be saved across crReturn */
5593 c_write_str(ssh
, "login as: ");
5595 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
5597 crWaitUntilV(!pktin
);
5598 ret
= process_userpass_input(ssh
, in
, inlen
);
5602 c_write_str(ssh
, "\r\n");
5604 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
5607 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
5608 s
->username
[sizeof(s
->username
)-1] = '\0';
5609 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
5610 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
5611 c_write_str(ssh
, stuff
);
5615 s
->got_username
= TRUE
;
5618 * Send an authentication request using method "none": (a)
5619 * just in case it succeeds, and (b) so that we know what
5620 * authentication methods we can usefully try next.
5622 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5624 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
5625 ssh2_pkt_addstring(s
->pktout
, s
->username
);
5626 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");/* service requested */
5627 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
5628 ssh2_pkt_send(ssh
, s
->pktout
);
5629 s
->type
= AUTH_TYPE_NONE
;
5631 s
->we_are_in
= FALSE
;
5633 s
->tried_pubkey_config
= FALSE
;
5634 s
->tried_agent
= FALSE
;
5635 s
->tried_keyb_inter
= FALSE
;
5636 s
->kbd_inter_running
= FALSE
;
5637 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
5638 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
5640 logeventf(ssh
, "Reading private key file \"%.150s\"",
5641 filename_to_str(&ssh
->cfg
.keyfile
));
5642 keytype
= key_type(&ssh
->cfg
.keyfile
);
5643 if (keytype
== SSH_KEYTYPE_SSH2
) {
5645 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
5646 &s
->publickey_bloblen
, NULL
);
5649 logeventf(ssh
, "Unable to use this key file (%s)",
5650 key_type_to_str(keytype
));
5651 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
5653 filename_to_str(&ssh
->cfg
.keyfile
),
5654 key_type_to_str(keytype
));
5655 c_write_str(ssh
, msgbuf
);
5657 s
->publickey_blob
= NULL
;
5660 s
->publickey_blob
= NULL
;
5664 * Wait for the result of the last authentication request.
5667 crWaitUntilV(pktin
);
5668 while (pktin
->type
== SSH2_MSG_USERAUTH_BANNER
) {
5672 * Don't show the banner if we're operating in
5673 * non-verbose non-interactive mode. (It's probably
5674 * a script, which means nobody will read the
5675 * banner _anyway_, and moreover the printing of
5676 * the banner will screw up processing on the
5677 * output of (say) plink.)
5679 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
5680 ssh_pkt_getstring(pktin
, &banner
, &size
);
5682 c_write_untrusted(ssh
, banner
, size
);
5684 crWaitUntilV(pktin
);
5686 if (pktin
->type
== SSH2_MSG_USERAUTH_SUCCESS
) {
5687 logevent("Access granted");
5688 s
->we_are_in
= TRUE
;
5692 if (s
->kbd_inter_running
&&
5693 pktin
->type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
5695 * This is either a further set-of-prompts packet
5696 * in keyboard-interactive authentication, or it's
5697 * the same one and we came back here with `gotit'
5698 * set. In the former case, we must reset the
5699 * curr_prompt variable.
5703 } else if (pktin
->type
!= SSH2_MSG_USERAUTH_FAILURE
) {
5704 bombout(("Strange packet received during authentication: type %d",
5712 * OK, we're now sitting on a USERAUTH_FAILURE message, so
5713 * we can look at the string in it and know what we can
5714 * helpfully try next.
5716 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
) {
5719 ssh_pkt_getstring(pktin
, &methods
, &methlen
);
5720 s
->kbd_inter_running
= FALSE
;
5721 if (!ssh2_pkt_getbool(pktin
)) {
5723 * We have received an unequivocal Access
5724 * Denied. This can translate to a variety of
5727 * - if we'd just tried "none" authentication,
5728 * it's not worth printing anything at all
5730 * - if we'd just tried a public key _offer_,
5731 * the message should be "Server refused our
5732 * key" (or no message at all if the key
5733 * came from Pageant)
5735 * - if we'd just tried anything else, the
5736 * message really should be "Access denied".
5738 * Additionally, if we'd just tried password
5739 * authentication, we should break out of this
5740 * whole loop so as to go back to the username
5741 * prompt (iff we're configured to allow
5742 * username change attempts).
5744 if (s
->type
== AUTH_TYPE_NONE
) {
5746 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
5747 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
5748 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
5749 c_write_str(ssh
, "Server refused our key\r\n");
5750 logevent("Server refused public key");
5751 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
5752 /* server declined keyboard-interactive; ignore */
5754 c_write_str(ssh
, "Access denied\r\n");
5755 logevent("Access denied");
5756 if (s
->type
== AUTH_TYPE_PASSWORD
&&
5757 ssh
->cfg
.change_username
) {
5758 /* XXX perhaps we should allow
5759 * keyboard-interactive to do this too? */
5760 s
->we_are_in
= FALSE
;
5765 c_write_str(ssh
, "Further authentication required\r\n");
5766 logevent("Further authentication required");
5770 in_commasep_string("publickey", methods
, methlen
);
5772 in_commasep_string("password", methods
, methlen
);
5773 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
5774 in_commasep_string("keyboard-interactive", methods
, methlen
);
5778 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5782 * Most password/passphrase prompts will be
5783 * non-echoing, so we set this to 0 by default.
5784 * Exception is that some keyboard-interactive prompts
5785 * can be echoing, in which case we'll set this to 1.
5789 if (!s
->method
&& s
->can_pubkey
&&
5790 agent_exists() && !s
->tried_agent
) {
5792 * Attempt public-key authentication using Pageant.
5797 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5798 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
5800 s
->tried_agent
= TRUE
;
5802 logevent("Pageant is running. Requesting keys.");
5804 /* Request the keys held by the agent. */
5805 PUT_32BIT(s
->request
, 1);
5806 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
5807 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
5808 ssh_agent_callback
, ssh
)) {
5812 bombout(("Unexpected data from server while"
5813 " waiting for agent response"));
5816 } while (pktin
|| inlen
> 0);
5817 r
= ssh
->agent_response
;
5818 s
->responselen
= ssh
->agent_response_len
;
5820 s
->response
= (unsigned char *) r
;
5821 if (s
->response
&& s
->responselen
>= 5 &&
5822 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
5823 s
->p
= s
->response
+ 5;
5824 s
->nkeys
= GET_32BIT(s
->p
);
5828 sprintf(buf
, "Pageant has %d SSH2 keys", s
->nkeys
);
5831 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
5836 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
5839 s
->pklen
= GET_32BIT(s
->p
);
5841 if (s
->publickey_blob
&&
5842 s
->pklen
== s
->publickey_bloblen
&&
5843 !memcmp(s
->p
, s
->publickey_blob
,
5844 s
->publickey_bloblen
)) {
5845 logevent("This key matches configured key file");
5846 s
->tried_pubkey_config
= 1;
5848 s
->pkblob
= (char *)s
->p
;
5850 s
->alglen
= GET_32BIT(s
->pkblob
);
5851 s
->alg
= s
->pkblob
+ 4;
5852 s
->commentlen
= GET_32BIT(s
->p
);
5854 s
->commentp
= (char *)s
->p
;
5855 s
->p
+= s
->commentlen
;
5856 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
5857 ssh2_pkt_addstring(s
->pktout
, s
->username
);
5858 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
5859 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
5860 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
5861 ssh2_pkt_addstring_start(s
->pktout
);
5862 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
5863 ssh2_pkt_addstring_start(s
->pktout
);
5864 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
5865 ssh2_pkt_send(ssh
, s
->pktout
);
5867 crWaitUntilV(pktin
);
5868 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
5869 logevent("Key refused");
5873 if (flags
& FLAG_VERBOSE
) {
5874 c_write_str(ssh
, "Authenticating with "
5876 c_write(ssh
, s
->commentp
, s
->commentlen
);
5877 c_write_str(ssh
, "\" from agent\r\n");
5881 * Server is willing to accept the key.
5882 * Construct a SIGN_REQUEST.
5884 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
5885 ssh2_pkt_addstring(s
->pktout
, s
->username
);
5886 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
5887 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
5888 ssh2_pkt_addbool(s
->pktout
, TRUE
);
5889 ssh2_pkt_addstring_start(s
->pktout
);
5890 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
5891 ssh2_pkt_addstring_start(s
->pktout
);
5892 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
5894 s
->siglen
= s
->pktout
->length
- 5 + 4 + 20;
5895 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
5897 s
->len
= 1; /* message type */
5898 s
->len
+= 4 + s
->pklen
; /* key blob */
5899 s
->len
+= 4 + s
->siglen
; /* data to sign */
5900 s
->len
+= 4; /* flags */
5901 s
->agentreq
= snewn(4 + s
->len
, char);
5902 PUT_32BIT(s
->agentreq
, s
->len
);
5903 s
->q
= s
->agentreq
+ 4;
5904 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
5905 PUT_32BIT(s
->q
, s
->pklen
);
5907 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
5909 PUT_32BIT(s
->q
, s
->siglen
);
5911 /* Now the data to be signed... */
5912 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
5913 PUT_32BIT(s
->q
, 20);
5916 memcpy(s
->q
, ssh
->v2_session_id
, 20);
5918 memcpy(s
->q
, s
->pktout
->data
+ 5,
5919 s
->pktout
->length
- 5);
5920 s
->q
+= s
->pktout
->length
- 5;
5921 /* And finally the (zero) flags word. */
5923 if (!agent_query(s
->agentreq
, s
->len
+ 4,
5925 ssh_agent_callback
, ssh
)) {
5929 bombout(("Unexpected data from server"
5930 " while waiting for agent"
5934 } while (pktin
|| inlen
> 0);
5935 vret
= ssh
->agent_response
;
5936 s
->retlen
= ssh
->agent_response_len
;
5941 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
5942 logevent("Sending Pageant's response");
5943 ssh2_add_sigblob(ssh
, s
->pktout
,
5944 s
->pkblob
, s
->pklen
,
5946 GET_32BIT(s
->ret
+ 5));
5947 ssh2_pkt_send(ssh
, s
->pktout
);
5952 ("Pageant failed to answer challenge");
5963 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
5964 && !s
->tried_pubkey_config
) {
5965 unsigned char *pub_blob
;
5966 char *algorithm
, *comment
;
5969 s
->tried_pubkey_config
= TRUE
;
5971 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5972 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
5975 * Try the public key supplied in the configuration.
5977 * First, offer the public blob to see if the server is
5978 * willing to accept it.
5981 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
5986 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
5987 ssh2_pkt_addstring(s
->pktout
, s
->username
);
5988 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
5989 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
5990 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
5991 ssh2_pkt_addstring(s
->pktout
, algorithm
);
5992 ssh2_pkt_addstring_start(s
->pktout
);
5993 ssh2_pkt_addstring_data(s
->pktout
, (char *)pub_blob
,
5995 ssh2_pkt_send(ssh
, s
->pktout
);
5996 logevent("Offered public key");
5998 crWaitUntilV(pktin
);
5999 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6001 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
6002 continue; /* key refused; give up on it */
6005 logevent("Offer of public key accepted");
6007 * Actually attempt a serious authentication using
6010 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
6011 sprintf(s
->pwprompt
,
6012 "Passphrase for key \"%.100s\": ",
6018 if (flags
& FLAG_VERBOSE
) {
6019 c_write_str(ssh
, "Authenticating with public key \"");
6020 c_write_str(ssh
, comment
);
6021 c_write_str(ssh
, "\"\r\n");
6023 s
->method
= AUTH_PUBLICKEY_FILE
;
6027 if (!s
->method
&& s
->can_keyb_inter
&& !s
->tried_keyb_inter
) {
6028 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6029 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6030 s
->tried_keyb_inter
= TRUE
;
6032 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6033 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6035 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6036 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6037 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6038 ssh2_pkt_addstring(s
->pktout
, "keyboard-interactive"); /* method */
6039 ssh2_pkt_addstring(s
->pktout
, ""); /* lang */
6040 ssh2_pkt_addstring(s
->pktout
, "");
6041 ssh2_pkt_send(ssh
, s
->pktout
);
6043 crWaitUntilV(pktin
);
6044 if (pktin
->type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6045 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
)
6047 logevent("Keyboard-interactive authentication refused");
6048 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
6052 s
->kbd_inter_running
= TRUE
;
6056 if (s
->kbd_inter_running
) {
6057 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6058 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6059 s
->tried_keyb_inter
= TRUE
;
6061 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6062 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6064 if (s
->curr_prompt
== 0) {
6066 * We've got a fresh USERAUTH_INFO_REQUEST.
6067 * Display header data, and start going through
6070 char *name
, *inst
, *lang
;
6071 int name_len
, inst_len
, lang_len
;
6073 ssh_pkt_getstring(pktin
, &name
, &name_len
);
6074 ssh_pkt_getstring(pktin
, &inst
, &inst_len
);
6075 ssh_pkt_getstring(pktin
, &lang
, &lang_len
);
6077 c_write_untrusted(ssh
, name
, name_len
);
6078 c_write_str(ssh
, "\r\n");
6081 c_write_untrusted(ssh
, inst
, inst_len
);
6082 c_write_str(ssh
, "\r\n");
6084 s
->num_prompts
= ssh_pkt_getuint32(pktin
);
6088 * If there are prompts remaining in the packet,
6089 * display one and get a response.
6091 if (s
->curr_prompt
< s
->num_prompts
) {
6095 ssh_pkt_getstring(pktin
, &prompt
, &prompt_len
);
6096 if (prompt_len
> 0) {
6097 static const char trunc
[] = "<prompt truncated>: ";
6098 static const int prlen
= sizeof(s
->pwprompt
) -
6100 if (prompt_len
> prlen
) {
6101 memcpy(s
->pwprompt
, prompt
, prlen
);
6102 strcpy(s
->pwprompt
+ prlen
, trunc
);
6104 memcpy(s
->pwprompt
, prompt
, prompt_len
);
6105 s
->pwprompt
[prompt_len
] = '\0';
6109 "<server failed to send prompt>: ");
6111 s
->echo
= ssh2_pkt_getbool(pktin
);
6117 if (!s
->method
&& s
->can_passwd
) {
6118 s
->method
= AUTH_PASSWORD
;
6119 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6120 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
6121 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
6128 if (!ssh_get_line(s
->pwprompt
, s
->password
,
6129 sizeof(s
->password
), TRUE
)) {
6131 * get_line failed to get a password (for
6132 * example because one was supplied on the
6133 * command line which has already failed to
6136 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6137 ssh2_pkt_adduint32(s
->pktout
,SSH2_DISCONNECT_BY_APPLICATION
);
6138 ssh2_pkt_addstring(s
->pktout
, "No more passwords available"
6140 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6141 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6142 logevent("Unable to authenticate");
6143 connection_fatal(ssh
->frontend
,
6144 "Unable to authenticate");
6145 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6149 int ret
; /* need not be saved across crReturn */
6150 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
6153 setup_userpass_input(ssh
, s
->password
,
6154 sizeof(s
->password
), s
->echo
);
6156 crWaitUntilV(!pktin
);
6157 ret
= process_userpass_input(ssh
, in
, inlen
);
6161 c_write_str(ssh
, "\r\n");
6165 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
6167 * We have our passphrase. Now try the actual authentication.
6169 struct ssh2_userkey
*key
;
6170 const char *error
= NULL
;
6172 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
,
6174 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
6175 if (key
== SSH2_WRONG_PASSPHRASE
) {
6176 c_write_str(ssh
, "Wrong passphrase\r\n");
6177 s
->tried_pubkey_config
= FALSE
;
6179 c_write_str(ssh
, "Unable to load private key (");
6180 c_write_str(ssh
, error
);
6181 c_write_str(ssh
, ")\r\n");
6182 s
->tried_pubkey_config
= TRUE
;
6184 /* Send a spurious AUTH_NONE to return to the top. */
6185 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6186 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6187 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6188 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6189 ssh2_pkt_send(ssh
, s
->pktout
);
6190 s
->type
= AUTH_TYPE_NONE
;
6192 unsigned char *pkblob
, *sigblob
, *sigdata
;
6193 int pkblob_len
, sigblob_len
, sigdata_len
;
6197 * We have loaded the private key and the server
6198 * has announced that it's willing to accept it.
6199 * Hallelujah. Generate a signature and send it.
6201 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6202 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6203 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6204 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6205 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6206 ssh2_pkt_addstring(s
->pktout
, key
->alg
->name
);
6207 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
6208 ssh2_pkt_addstring_start(s
->pktout
);
6209 ssh2_pkt_addstring_data(s
->pktout
, (char *)pkblob
, pkblob_len
);
6212 * The data to be signed is:
6216 * followed by everything so far placed in the
6219 sigdata_len
= s
->pktout
->length
- 5 + 4 + 20;
6220 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6222 sigdata
= snewn(sigdata_len
, unsigned char);
6224 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6225 PUT_32BIT(sigdata
+p
, 20);
6228 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
6229 memcpy(sigdata
+p
, s
->pktout
->data
+ 5,
6230 s
->pktout
->length
- 5);
6231 p
+= s
->pktout
->length
- 5;
6232 assert(p
== sigdata_len
);
6233 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
6234 sigdata_len
, &sigblob_len
);
6235 ssh2_add_sigblob(ssh
, s
->pktout
, pkblob
, pkblob_len
,
6236 sigblob
, sigblob_len
);
6241 ssh2_pkt_send(ssh
, s
->pktout
);
6242 s
->type
= AUTH_TYPE_PUBLICKEY
;
6243 key
->alg
->freekey(key
->data
);
6245 } else if (s
->method
== AUTH_PASSWORD
) {
6247 * We send the password packet lumped tightly together with
6248 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
6249 * string long enough to make the total length of the two
6250 * packets constant. This should ensure that a passive
6251 * listener doing traffic analyis can't work out the length
6254 * For this to work, we need an assumption about the
6255 * maximum length of the password packet. I think 256 is
6256 * pretty conservative. Anyone using a password longer than
6257 * that probably doesn't have much to worry about from
6258 * people who find out how long their password is!
6260 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6261 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6262 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6263 ssh2_pkt_addstring(s
->pktout
, "password");
6264 ssh2_pkt_addbool(s
->pktout
, FALSE
);
6265 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6266 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6267 memset(s
->password
, 0, sizeof(s
->password
));
6268 end_log_omission(ssh
, s
->pktout
);
6269 ssh2_pkt_defer(ssh
, s
->pktout
);
6271 * We'll include a string that's an exact multiple of the
6272 * cipher block size. If the cipher is NULL for some
6273 * reason, we don't do this trick at all because we gain
6276 if (ssh
->cscipher
) {
6279 stringlen
= (256 - ssh
->deferred_len
);
6280 stringlen
+= ssh
->cscipher
->blksize
- 1;
6281 stringlen
-= (stringlen
% ssh
->cscipher
->blksize
);
6284 * Temporarily disable actual compression,
6285 * so we can guarantee to get this string
6286 * exactly the length we want it. The
6287 * compression-disabling routine should
6288 * return an integer indicating how many
6289 * bytes we should adjust our string length
6293 ssh
->cscomp
->disable_compression(ssh
->cs_comp_ctx
);
6295 s
->pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
6296 ssh2_pkt_addstring_start(s
->pktout
);
6297 for (i
= 0; i
< stringlen
; i
++) {
6298 char c
= (char) random_byte();
6299 ssh2_pkt_addstring_data(s
->pktout
, &c
, 1);
6301 ssh2_pkt_defer(ssh
, s
->pktout
);
6303 ssh_pkt_defersend(ssh
);
6304 logevent("Sent password");
6305 s
->type
= AUTH_TYPE_PASSWORD
;
6306 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
6307 if (s
->curr_prompt
== 0) {
6308 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
6309 ssh2_pkt_adduint32(s
->pktout
, s
->num_prompts
);
6311 if (s
->need_pw
) { /* only add pw if we just got one! */
6312 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6313 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6314 memset(s
->password
, 0, sizeof(s
->password
));
6315 end_log_omission(ssh
, s
->pktout
);
6318 if (s
->curr_prompt
>= s
->num_prompts
) {
6319 ssh2_pkt_send(ssh
, s
->pktout
);
6322 * If there are prompts remaining, we set
6323 * `gotit' so that we won't attempt to get
6324 * another packet. Then we go back round the
6325 * loop and will end up retrieving another
6326 * prompt out of the existing packet. Funky or
6331 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6333 c_write_str(ssh
, "No supported authentication methods"
6334 " left to try!\r\n");
6335 logevent("No supported authentications offered."
6337 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6338 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
6339 ssh2_pkt_addstring(s
->pktout
, "No supported authentication"
6340 " methods available");
6341 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6342 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6343 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6347 } while (!s
->we_are_in
);
6350 * Now we're authenticated for the connection protocol. The
6351 * connection protocol will automatically have started at this
6352 * point; there's no need to send SERVICE_REQUEST.
6355 ssh
->channels
= newtree234(ssh_channelcmp
);
6358 * Set up handlers for some connection protocol messages, so we
6359 * don't have to handle them repeatedly in this coroutine.
6361 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] =
6362 ssh2_msg_channel_window_adjust
;
6363 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] =
6364 ssh2_msg_global_request
;
6367 * Create the main session channel.
6369 if (!ssh
->cfg
.ssh_no_shell
) {
6370 ssh
->mainchan
= snew(struct ssh_channel
);
6371 ssh
->mainchan
->ssh
= ssh
;
6372 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
6373 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
6374 ssh2_pkt_addstring(s
->pktout
, "session");
6375 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->localid
);
6376 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6377 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
6378 ssh2_pkt_adduint32(s
->pktout
, 0x4000UL
); /* our max pkt size */
6379 ssh2_pkt_send(ssh
, s
->pktout
);
6380 crWaitUntilV(pktin
);
6381 if (pktin
->type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
6382 bombout(("Server refused to open a session"));
6384 /* FIXME: error data comes back in FAILURE packet */
6386 if (ssh_pkt_getuint32(pktin
) != ssh
->mainchan
->localid
) {
6387 bombout(("Server's channel confirmation cited wrong channel"));
6390 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(pktin
);
6391 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
6392 ssh
->mainchan
->closes
= 0;
6393 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
6394 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
6395 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
6396 add234(ssh
->channels
, ssh
->mainchan
);
6397 update_specials_menu(ssh
->frontend
);
6398 logevent("Opened channel for session");
6400 ssh
->mainchan
= NULL
;
6403 * Now we have a channel, make dispatch table entries for
6404 * general channel-based messages.
6406 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] =
6407 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] =
6408 ssh2_msg_channel_data
;
6409 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = ssh2_msg_channel_eof
;
6410 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = ssh2_msg_channel_close
;
6411 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] =
6412 ssh2_msg_channel_open_confirmation
;
6413 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] =
6414 ssh2_msg_channel_open_failure
;
6415 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] =
6416 ssh2_msg_channel_request
;
6417 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] =
6418 ssh2_msg_channel_open
;
6421 * Potentially enable X11 forwarding.
6423 if (ssh
->mainchan
&& ssh
->cfg
.x11_forward
) {
6424 char proto
[20], data
[64];
6425 logevent("Requesting X11 forwarding");
6426 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
6427 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
6428 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
6429 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6430 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6431 ssh2_pkt_addstring(s
->pktout
, "x11-req");
6432 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6433 ssh2_pkt_addbool(s
->pktout
, 0); /* many connections */
6434 ssh2_pkt_addstring(s
->pktout
, proto
);
6435 ssh2_pkt_addstring(s
->pktout
, data
);
6436 ssh2_pkt_adduint32(s
->pktout
, x11_get_screen_number(ssh
->cfg
.x11_display
));
6437 ssh2_pkt_send(ssh
, s
->pktout
);
6439 crWaitUntilV(pktin
);
6441 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6442 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6443 bombout(("Unexpected response to X11 forwarding request:"
6444 " packet type %d", pktin
->type
));
6447 logevent("X11 forwarding refused");
6449 logevent("X11 forwarding enabled");
6450 ssh
->X11_fwd_enabled
= TRUE
;
6455 * Enable port forwardings.
6460 int sport
,dport
,sserv
,dserv
;
6461 char sports
[256], dports
[256], saddr
[256], host
[256];
6463 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
6464 /* Add port forwardings. */
6465 ssh
->portfwd_strptr
= ssh
->cfg
.portfwd
;
6466 while (*ssh
->portfwd_strptr
) {
6467 type
= *ssh
->portfwd_strptr
++;
6470 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= '\t') {
6471 if (*ssh
->portfwd_strptr
== ':') {
6473 * We've seen a colon in the middle of the
6474 * source port number. This means that
6475 * everything we've seen until now is the
6476 * source _address_, so we'll move it into
6477 * saddr and start sports from the beginning
6480 ssh
->portfwd_strptr
++;
6482 strcpy(saddr
, sports
);
6485 if (n
< 255) sports
[n
++] = *ssh
->portfwd_strptr
++;
6489 if (*ssh
->portfwd_strptr
== '\t')
6490 ssh
->portfwd_strptr
++;
6492 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= ':') {
6493 if (n
< 255) host
[n
++] = *ssh
->portfwd_strptr
++;
6496 if (*ssh
->portfwd_strptr
== ':')
6497 ssh
->portfwd_strptr
++;
6499 while (*ssh
->portfwd_strptr
) {
6500 if (n
< 255) dports
[n
++] = *ssh
->portfwd_strptr
++;
6503 ssh
->portfwd_strptr
++;
6504 dport
= atoi(dports
);
6508 dport
= net_service_lookup(dports
);
6510 logeventf(ssh
, "Service lookup failed for destination"
6511 " port \"%s\"", dports
);
6515 while (*ssh
->portfwd_strptr
) ssh
->portfwd_strptr
++;
6517 ssh
->portfwd_strptr
++; /* eat the NUL and move to next one */
6519 sport
= atoi(sports
);
6523 sport
= net_service_lookup(sports
);
6525 logeventf(ssh
, "Service lookup failed for source"
6526 " port \"%s\"", sports
);
6529 if (sport
&& dport
) {
6530 /* Set up a description of the source port. */
6531 static char *sportdesc
;
6532 sportdesc
= dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
6533 (int)(*saddr?
strlen(saddr
):0), *saddr?saddr
:NULL
,
6534 (int)(*saddr?
1:0), ":",
6535 (int)(sserv ?
strlen(sports
) : 0), sports
,
6536 sserv
, "(", sport
, sserv
, ")");
6538 /* Verbose description of the destination port */
6539 char *dportdesc
= dupprintf("%s:%.*s%.*s%d%.*s",
6541 (int)(dserv ?
strlen(dports
) : 0), dports
,
6542 dserv
, "(", dport
, dserv
, ")");
6543 const char *err
= pfd_addforward(host
, dport
,
6544 *saddr ? saddr
: NULL
,
6545 sport
, ssh
, &ssh
->cfg
);
6547 logeventf(ssh
, "Local port %s forward to %s"
6548 " failed: %s", sportdesc
, dportdesc
, err
);
6550 logeventf(ssh
, "Local port %s forwarding to %s",
6551 sportdesc
, dportdesc
);
6554 } else if (type
== 'D') {
6555 const char *err
= pfd_addforward(NULL
, -1,
6556 *saddr ? saddr
: NULL
,
6557 sport
, ssh
, &ssh
->cfg
);
6559 logeventf(ssh
, "Local port %s SOCKS dynamic forward"
6560 " setup failed: %s", sportdesc
, err
);
6562 logeventf(ssh
, "Local port %s doing SOCKS"
6563 " dynamic forwarding", sportdesc
);
6566 struct ssh_rportfwd
*pf
;
6567 pf
= snew(struct ssh_rportfwd
);
6568 strcpy(pf
->dhost
, host
);
6571 if (add234(ssh
->rportfwds
, pf
) != pf
) {
6572 logeventf(ssh
, "Duplicate remote port forwarding"
6573 " to %s:%d", host
, dport
);
6576 logeventf(ssh
, "Requesting remote port %s"
6577 " forward to %s:%.*s%.*s%d%.*s",
6580 (int)(dserv ?
strlen(dports
) : 0), dports
,
6581 dserv
, "(", dport
, dserv
, ")");
6582 s
->pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
6583 ssh2_pkt_addstring(s
->pktout
, "tcpip-forward");
6584 ssh2_pkt_addbool(s
->pktout
, 1);/* want reply */
6586 ssh2_pkt_addstring(s
->pktout
, saddr
);
6587 } else if (ssh
->cfg
.rport_acceptall
) {
6588 ssh2_pkt_addstring(s
->pktout
, "0.0.0.0");
6590 ssh2_pkt_addstring(s
->pktout
, "127.0.0.1");
6592 ssh2_pkt_adduint32(s
->pktout
, sport
);
6593 ssh2_pkt_send(ssh
, s
->pktout
);
6595 crWaitUntilV(pktin
);
6597 if (pktin
->type
!= SSH2_MSG_REQUEST_SUCCESS
) {
6598 if (pktin
->type
!= SSH2_MSG_REQUEST_FAILURE
) {
6599 bombout(("Unexpected response to port "
6600 "forwarding request: packet type %d",
6604 logevent("Server refused this port forwarding");
6606 logevent("Remote port forwarding enabled");
6616 * Potentially enable agent forwarding.
6618 if (ssh
->mainchan
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
6619 logevent("Requesting OpenSSH-style agent forwarding");
6620 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6621 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6622 ssh2_pkt_addstring(s
->pktout
, "auth-agent-req@openssh.com");
6623 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6624 ssh2_pkt_send(ssh
, s
->pktout
);
6626 crWaitUntilV(pktin
);
6628 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6629 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6630 bombout(("Unexpected response to agent forwarding request:"
6631 " packet type %d", pktin
->type
));
6634 logevent("Agent forwarding refused");
6636 logevent("Agent forwarding enabled");
6637 ssh
->agentfwd_enabled
= TRUE
;
6642 * Now allocate a pty for the session.
6644 if (ssh
->mainchan
&& !ssh
->cfg
.nopty
) {
6645 /* Unpick the terminal-speed string. */
6646 /* XXX perhaps we should allow no speeds to be sent. */
6647 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
6648 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
6649 /* Build the pty request. */
6650 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6651 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
6652 ssh2_pkt_addstring(s
->pktout
, "pty-req");
6653 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6654 ssh2_pkt_addstring(s
->pktout
, ssh
->cfg
.termtype
);
6655 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_width
);
6656 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_height
);
6657 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel width */
6658 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel height */
6659 ssh2_pkt_addstring_start(s
->pktout
);
6660 ssh2_pkt_addbyte(s
->pktout
, 128); /* TTY_OP_ISPEED */
6661 ssh2_pkt_adduint32(s
->pktout
, ssh
->ispeed
);
6662 ssh2_pkt_addbyte(s
->pktout
, 129); /* TTY_OP_OSPEED */
6663 ssh2_pkt_adduint32(s
->pktout
, ssh
->ospeed
);
6664 ssh2_pkt_addstring_data(s
->pktout
, "\0", 1); /* TTY_OP_END */
6665 ssh2_pkt_send(ssh
, s
->pktout
);
6666 ssh
->state
= SSH_STATE_INTERMED
;
6668 crWaitUntilV(pktin
);
6670 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6671 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6672 bombout(("Unexpected response to pty request:"
6673 " packet type %d", pktin
->type
));
6676 c_write_str(ssh
, "Server refused to allocate pty\r\n");
6677 ssh
->editing
= ssh
->echoing
= 1;
6679 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
6680 ssh
->ospeed
, ssh
->ispeed
);
6683 ssh
->editing
= ssh
->echoing
= 1;
6687 * Send environment variables.
6689 * Simplest thing here is to send all the requests at once, and
6690 * then wait for a whole bunch of successes or failures.
6692 if (ssh
->mainchan
&& *ssh
->cfg
.environmt
) {
6693 char *e
= ssh
->cfg
.environmt
;
6694 char *var
, *varend
, *val
;
6700 while (*e
&& *e
!= '\t') e
++;
6702 if (*e
== '\t') e
++;
6707 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6708 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6709 ssh2_pkt_addstring(s
->pktout
, "env");
6710 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6711 ssh2_pkt_addstring_start(s
->pktout
);
6712 ssh2_pkt_addstring_data(s
->pktout
, var
, varend
-var
);
6713 ssh2_pkt_addstring(s
->pktout
, val
);
6714 ssh2_pkt_send(ssh
, s
->pktout
);
6719 logeventf(ssh
, "Sent %d environment variables", s
->num_env
);
6722 s
->env_left
= s
->num_env
;
6724 while (s
->env_left
> 0) {
6725 crWaitUntilV(pktin
);
6727 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6728 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6729 bombout(("Unexpected response to environment request:"
6730 " packet type %d", pktin
->type
));
6740 if (s
->env_ok
== s
->num_env
) {
6741 logevent("All environment variables successfully set");
6742 } else if (s
->env_ok
== 0) {
6743 logevent("All environment variables refused");
6744 c_write_str(ssh
, "Server refused to set environment variables\r\n");
6746 logeventf(ssh
, "%d environment variables refused",
6747 s
->num_env
- s
->env_ok
);
6748 c_write_str(ssh
, "Server refused to set all environment variables\r\n");
6753 * Start a shell or a remote command. We may have to attempt
6754 * this twice if the config data has provided a second choice
6757 if (ssh
->mainchan
) while (1) {
6761 if (ssh
->fallback_cmd
) {
6762 subsys
= ssh
->cfg
.ssh_subsys2
;
6763 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
6765 subsys
= ssh
->cfg
.ssh_subsys
;
6766 cmd
= ssh
->cfg
.remote_cmd_ptr
;
6769 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6770 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
6772 ssh2_pkt_addstring(s
->pktout
, "subsystem");
6773 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6774 ssh2_pkt_addstring(s
->pktout
, cmd
);
6776 ssh2_pkt_addstring(s
->pktout
, "exec");
6777 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6778 ssh2_pkt_addstring(s
->pktout
, cmd
);
6780 ssh2_pkt_addstring(s
->pktout
, "shell");
6781 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6783 ssh2_pkt_send(ssh
, s
->pktout
);
6785 crWaitUntilV(pktin
);
6787 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6788 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6789 bombout(("Unexpected response to shell/command request:"
6790 " packet type %d", pktin
->type
));
6794 * We failed to start the command. If this is the
6795 * fallback command, we really are finished; if it's
6796 * not, and if the fallback command exists, try falling
6797 * back to it before complaining.
6799 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
6800 logevent("Primary command failed; attempting fallback");
6801 ssh
->fallback_cmd
= TRUE
;
6804 bombout(("Server refused to start a shell/command"));
6807 logevent("Started a shell/command");
6812 ssh
->state
= SSH_STATE_SESSION
;
6813 if (ssh
->size_needed
)
6814 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
6815 if (ssh
->eof_needed
)
6816 ssh_special(ssh
, TS_EOF
);
6822 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
6827 s
->try_send
= FALSE
;
6831 * _All_ the connection-layer packets we expect to
6832 * receive are now handled by the dispatch table.
6833 * Anything that reaches here must be bogus.
6836 bombout(("Strange packet received: type %d", pktin
->type
));
6838 } else if (ssh
->mainchan
) {
6840 * We have spare data. Add it to the channel buffer.
6842 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
6847 struct ssh_channel
*c
;
6849 * Try to send data on all channels if we can.
6851 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
6854 continue; /* don't send on closing channels */
6855 bufsize
= ssh2_try_send(c
);
6858 case CHAN_MAINSESSION
:
6859 /* stdin need not receive an unthrottle
6860 * notification since it will be polled */
6863 x11_unthrottle(c
->u
.x11
.s
);
6866 /* agent sockets are request/response and need no
6867 * buffer management */
6870 pfd_unthrottle(c
->u
.pfd
.s
);
6882 * Handlers for SSH2 messages that might arrive at any moment.
6884 void ssh2_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
6886 /* log reason code in disconnect message */
6888 int nowlen
, reason
, msglen
;
6890 reason
= ssh_pkt_getuint32(pktin
);
6891 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
6893 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
6894 buf
= dupprintf("Received disconnect message (%s)",
6895 ssh2_disconnect_reasons
[reason
]);
6897 buf
= dupprintf("Received disconnect message (unknown"
6898 " type %d)", reason
);
6902 buf
= dupprintf("Disconnection message text: %n%.*s",
6903 &nowlen
, msglen
, msg
);
6905 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
6907 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
6908 ssh2_disconnect_reasons
[reason
] : "unknown",
6913 void ssh2_msg_debug(Ssh ssh
, struct Packet
*pktin
)
6915 /* log the debug message */
6920 /* XXX maybe we should actually take notice of this */
6921 always_display
= ssh2_pkt_getbool(pktin
);
6922 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
6924 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
6929 void ssh2_msg_something_unimplemented(Ssh ssh
, struct Packet
*pktin
)
6931 struct Packet
*pktout
;
6932 pktout
= ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
6933 ssh2_pkt_adduint32(pktout
, pktin
->sequence
);
6935 * UNIMPLEMENTED messages MUST appear in the same order as the
6936 * messages they respond to. Hence, never queue them.
6938 ssh2_pkt_send_noqueue(ssh
, pktout
);
6942 * Handle the top-level SSH2 protocol.
6944 static void ssh2_protocol_setup(Ssh ssh
)
6949 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
6951 for (i
= 0; i
< 256; i
++)
6952 ssh
->packet_dispatch
[i
] = ssh2_msg_something_unimplemented
;
6955 * Any message we actually understand, we set to NULL so that
6956 * the coroutines will get it.
6958 ssh
->packet_dispatch
[SSH2_MSG_UNIMPLEMENTED
] = NULL
;
6959 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_REQUEST
] = NULL
;
6960 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_ACCEPT
] = NULL
;
6961 ssh
->packet_dispatch
[SSH2_MSG_KEXINIT
] = NULL
;
6962 ssh
->packet_dispatch
[SSH2_MSG_NEWKEYS
] = NULL
;
6963 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_INIT
] = NULL
;
6964 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_REPLY
] = NULL
;
6965 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
6966 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
6967 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_INIT
] = NULL
;
6968 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_REPLY
] = NULL
;
6969 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_REQUEST
] = NULL
;
6970 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_FAILURE
] = NULL
;
6971 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_SUCCESS
] = NULL
;
6972 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
6973 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_PK_OK
] = NULL
;
6974 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
6975 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
6976 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_INFO_RESPONSE
] = NULL
;
6977 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] = NULL
;
6978 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_SUCCESS
] = NULL
;
6979 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_FAILURE
] = NULL
;
6980 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] = NULL
;
6981 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] = NULL
;
6982 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] = NULL
;
6983 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] = NULL
;
6984 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] = NULL
;
6985 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] = NULL
;
6986 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = NULL
;
6987 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = NULL
;
6988 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] = NULL
;
6989 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_SUCCESS
] = NULL
;
6990 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_FAILURE
] = NULL
;
6993 * These special message types we install handlers for.
6995 ssh
->packet_dispatch
[SSH2_MSG_DISCONNECT
] = ssh2_msg_disconnect
;
6996 ssh
->packet_dispatch
[SSH2_MSG_IGNORE
] = ssh_msg_ignore
; /* shared with ssh1 */
6997 ssh
->packet_dispatch
[SSH2_MSG_DEBUG
] = ssh2_msg_debug
;
7000 static void ssh2_timer(void *ctx
, long now
)
7004 if (!ssh
->kex_in_progress
&&
7005 now
- ssh
->next_rekey
>= 0) {
7006 do_ssh2_transport(ssh
, "Initiating key re-exchange (timeout)",
7011 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
7012 struct Packet
*pktin
)
7014 if (ssh
->state
== SSH_STATE_CLOSED
)
7018 ssh
->incoming_data_size
+= pktin
->encrypted_len
;
7019 if (!ssh
->kex_in_progress
&&
7020 ssh
->incoming_data_size
> MAX_DATA_BEFORE_REKEY
)
7021 do_ssh2_transport(ssh
, "Initiating key re-exchange "
7022 "(too much data received)", -1, NULL
);
7025 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
7026 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
7030 if (!ssh
->protocol_initial_phase_done
||
7031 (pktin
&& pktin
->type
>= 20 && pktin
->type
< 50)) {
7032 if (do_ssh2_transport(ssh
, in
, inlen
, pktin
) &&
7033 !ssh
->protocol_initial_phase_done
) {
7034 ssh
->protocol_initial_phase_done
= TRUE
;
7036 * Allow authconn to initialise itself.
7038 do_ssh2_authconn(ssh
, NULL
, 0, NULL
);
7041 do_ssh2_authconn(ssh
, in
, inlen
, pktin
);
7046 * Called to set up the connection.
7048 * Returns an error message, or NULL on success.
7050 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
7052 char *host
, int port
, char **realhost
, int nodelay
,
7058 ssh
= snew(struct ssh_tag
);
7059 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7060 ssh
->version
= 0; /* when not ready yet */
7063 ssh
->v1_cipher_ctx
= NULL
;
7064 ssh
->crcda_ctx
= NULL
;
7065 ssh
->cscipher
= NULL
;
7066 ssh
->cs_cipher_ctx
= NULL
;
7067 ssh
->sccipher
= NULL
;
7068 ssh
->sc_cipher_ctx
= NULL
;
7070 ssh
->cs_mac_ctx
= NULL
;
7072 ssh
->sc_mac_ctx
= NULL
;
7074 ssh
->cs_comp_ctx
= NULL
;
7076 ssh
->sc_comp_ctx
= NULL
;
7078 ssh
->kex_ctx
= NULL
;
7079 ssh
->hostkey
= NULL
;
7081 ssh
->state
= SSH_STATE_PREPACKET
;
7082 ssh
->size_needed
= FALSE
;
7083 ssh
->eof_needed
= FALSE
;
7086 ssh
->deferred_send_data
= NULL
;
7087 ssh
->deferred_len
= 0;
7088 ssh
->deferred_size
= 0;
7089 ssh
->fallback_cmd
= 0;
7091 ssh
->x11auth
= NULL
;
7092 ssh
->v1_compressing
= FALSE
;
7093 ssh
->v2_outgoing_sequence
= 0;
7094 ssh
->ssh1_rdpkt_crstate
= 0;
7095 ssh
->ssh2_rdpkt_crstate
= 0;
7096 ssh
->do_ssh_init_crstate
= 0;
7097 ssh
->ssh_gotdata_crstate
= 0;
7098 ssh
->do_ssh1_connection_crstate
= 0;
7099 ssh
->do_ssh1_login_crstate
= 0;
7100 ssh
->do_ssh2_transport_crstate
= 0;
7101 ssh
->do_ssh2_authconn_crstate
= 0;
7102 ssh
->do_ssh_init_state
= NULL
;
7103 ssh
->do_ssh1_login_state
= NULL
;
7104 ssh
->do_ssh2_transport_state
= NULL
;
7105 ssh
->do_ssh2_authconn_state
= NULL
;
7106 ssh
->mainchan
= NULL
;
7107 ssh
->throttled_all
= 0;
7108 ssh
->v1_stdout_throttling
= 0;
7110 ssh
->queuelen
= ssh
->queuesize
= 0;
7111 ssh
->queueing
= FALSE
;
7113 *backend_handle
= ssh
;
7116 if (crypto_startup() == 0)
7117 return "Microsoft high encryption pack not installed!";
7120 ssh
->frontend
= frontend_handle
;
7121 ssh
->term_width
= ssh
->cfg
.width
;
7122 ssh
->term_height
= ssh
->cfg
.height
;
7124 ssh
->channels
= NULL
;
7125 ssh
->rportfwds
= NULL
;
7130 ssh
->v1_throttle_count
= 0;
7131 ssh
->overall_bufsize
= 0;
7132 ssh
->fallback_cmd
= 0;
7134 ssh
->protocol
= NULL
;
7136 ssh
->protocol_initial_phase_done
= FALSE
;
7140 ssh
->incoming_data_size
= ssh
->outgoing_data_size
=
7141 ssh
->deferred_data_size
= 0L;
7142 ssh
->kex_in_progress
= FALSE
;
7144 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
7151 static void ssh_free(void *handle
)
7153 Ssh ssh
= (Ssh
) handle
;
7154 struct ssh_channel
*c
;
7155 struct ssh_rportfwd
*pf
;
7157 if (ssh
->v1_cipher_ctx
)
7158 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
7159 if (ssh
->cs_cipher_ctx
)
7160 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
7161 if (ssh
->sc_cipher_ctx
)
7162 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
7163 if (ssh
->cs_mac_ctx
)
7164 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
7165 if (ssh
->sc_mac_ctx
)
7166 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
7167 if (ssh
->cs_comp_ctx
) {
7169 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
7171 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
7173 if (ssh
->sc_comp_ctx
) {
7175 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
7177 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
7180 dh_cleanup(ssh
->kex_ctx
);
7181 sfree(ssh
->savedhost
);
7183 while (ssh
->queuelen
-- > 0)
7184 ssh_free_packet(ssh
->queue
[ssh
->queuelen
]);
7187 if (ssh
->channels
) {
7188 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
7191 if (c
->u
.x11
.s
!= NULL
)
7192 x11_close(c
->u
.x11
.s
);
7195 if (c
->u
.pfd
.s
!= NULL
)
7196 pfd_close(c
->u
.pfd
.s
);
7201 freetree234(ssh
->channels
);
7204 if (ssh
->rportfwds
) {
7205 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
7207 freetree234(ssh
->rportfwds
);
7209 sfree(ssh
->deferred_send_data
);
7211 x11_free_auth(ssh
->x11auth
);
7212 sfree(ssh
->do_ssh_init_state
);
7213 sfree(ssh
->do_ssh1_login_state
);
7214 sfree(ssh
->do_ssh2_transport_state
);
7215 sfree(ssh
->do_ssh2_authconn_state
);
7216 if (ssh
->crcda_ctx
) {
7217 crcda_free_context(ssh
->crcda_ctx
);
7218 ssh
->crcda_ctx
= NULL
;
7222 expire_timer_context(ssh
);
7225 pinger_free(ssh
->pinger
);
7229 * Reconfigure the SSH backend.
7231 * Currently, this function does nothing very useful. In future,
7232 * however, we could do some handy things with it. For example, we
7233 * could make the port forwarding configurer active in the Change
7234 * Settings box, and this routine could close down existing
7235 * forwardings and open up new ones in response to changes.
7237 static void ssh_reconfig(void *handle
, Config
*cfg
)
7239 Ssh ssh
= (Ssh
) handle
;
7240 pinger_reconfig(ssh
->pinger
, &ssh
->cfg
, cfg
);
7241 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7245 * Called to send data down the Telnet connection.
7247 static int ssh_send(void *handle
, char *buf
, int len
)
7249 Ssh ssh
= (Ssh
) handle
;
7251 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7254 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
7256 return ssh_sendbuffer(ssh
);
7260 * Called to query the current amount of buffered stdin data.
7262 static int ssh_sendbuffer(void *handle
)
7264 Ssh ssh
= (Ssh
) handle
;
7267 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7271 * If the SSH socket itself has backed up, add the total backup
7272 * size on that to any individual buffer on the stdin channel.
7275 if (ssh
->throttled_all
)
7276 override_value
= ssh
->overall_bufsize
;
7278 if (ssh
->version
== 1) {
7279 return override_value
;
7280 } else if (ssh
->version
== 2) {
7281 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
7282 return override_value
;
7284 return (override_value
+
7285 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
7292 * Called to set the size of the window from SSH's POV.
7294 static void ssh_size(void *handle
, int width
, int height
)
7296 Ssh ssh
= (Ssh
) handle
;
7297 struct Packet
*pktout
;
7299 ssh
->term_width
= width
;
7300 ssh
->term_height
= height
;
7302 switch (ssh
->state
) {
7303 case SSH_STATE_BEFORE_SIZE
:
7304 case SSH_STATE_PREPACKET
:
7305 case SSH_STATE_CLOSED
:
7306 break; /* do nothing */
7307 case SSH_STATE_INTERMED
:
7308 ssh
->size_needed
= TRUE
; /* buffer for later */
7310 case SSH_STATE_SESSION
:
7311 if (!ssh
->cfg
.nopty
) {
7312 if (ssh
->version
== 1) {
7313 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
7314 PKT_INT
, ssh
->term_height
,
7315 PKT_INT
, ssh
->term_width
,
7316 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
7317 } else if (ssh
->mainchan
) {
7318 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7319 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7320 ssh2_pkt_addstring(pktout
, "window-change");
7321 ssh2_pkt_addbool(pktout
, 0);
7322 ssh2_pkt_adduint32(pktout
, ssh
->term_width
);
7323 ssh2_pkt_adduint32(pktout
, ssh
->term_height
);
7324 ssh2_pkt_adduint32(pktout
, 0);
7325 ssh2_pkt_adduint32(pktout
, 0);
7326 ssh2_pkt_send(ssh
, pktout
);
7334 * Return a list of the special codes that make sense in this
7337 static const struct telnet_special
*ssh_get_specials(void *handle
)
7339 static const struct telnet_special ignore_special
[] = {
7340 {"IGNORE message", TS_NOP
},
7341 {"Repeat key exchange", TS_REKEY
},
7343 static const struct telnet_special ssh2_session_specials
[] = {
7346 /* These are the signal names defined by draft-ietf-secsh-connect-19.
7347 * They include all the ISO C signals, but are a subset of the POSIX
7348 * required signals. */
7349 {"SIGINT (Interrupt)", TS_SIGINT
},
7350 {"SIGTERM (Terminate)", TS_SIGTERM
},
7351 {"SIGKILL (Kill)", TS_SIGKILL
},
7352 {"SIGQUIT (Quit)", TS_SIGQUIT
},
7353 {"SIGHUP (Hangup)", TS_SIGHUP
},
7354 {"More signals", TS_SUBMENU
},
7355 {"SIGABRT", TS_SIGABRT
}, {"SIGALRM", TS_SIGALRM
},
7356 {"SIGFPE", TS_SIGFPE
}, {"SIGILL", TS_SIGILL
},
7357 {"SIGPIPE", TS_SIGPIPE
}, {"SIGSEGV", TS_SIGSEGV
},
7358 {"SIGUSR1", TS_SIGUSR1
}, {"SIGUSR2", TS_SIGUSR2
},
7361 static const struct telnet_special specials_end
[] = {
7364 static struct telnet_special ssh_specials
[lenof(ignore_special
) +
7365 lenof(ssh2_session_specials
) +
7366 lenof(specials_end
)];
7367 Ssh ssh
= (Ssh
) handle
;
7369 #define ADD_SPECIALS(name) \
7371 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7372 memcpy(&ssh_specials[i], name, sizeof name); \
7376 if (ssh
->version
== 1) {
7377 /* Don't bother offering IGNORE if we've decided the remote
7378 * won't cope with it, since we wouldn't bother sending it if
7380 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7381 ADD_SPECIALS(ignore_special
);
7382 } else if (ssh
->version
== 2) {
7383 ADD_SPECIALS(ignore_special
);
7385 ADD_SPECIALS(ssh2_session_specials
);
7386 } /* else we're not ready yet */
7389 ADD_SPECIALS(specials_end
);
7390 return ssh_specials
;
7398 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7399 * can send an EOF and collect resulting output (e.g. `plink
7402 static void ssh_special(void *handle
, Telnet_Special code
)
7404 Ssh ssh
= (Ssh
) handle
;
7405 struct Packet
*pktout
;
7407 if (code
== TS_EOF
) {
7408 if (ssh
->state
!= SSH_STATE_SESSION
) {
7410 * Buffer the EOF in case we are pre-SESSION, so we can
7411 * send it as soon as we reach SESSION.
7414 ssh
->eof_needed
= TRUE
;
7417 if (ssh
->version
== 1) {
7418 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
7419 } else if (ssh
->mainchan
) {
7420 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
7421 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7422 ssh2_pkt_send(ssh
, pktout
);
7424 logevent("Sent EOF message");
7425 } else if (code
== TS_PING
|| code
== TS_NOP
) {
7426 if (ssh
->state
== SSH_STATE_CLOSED
7427 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7428 if (ssh
->version
== 1) {
7429 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7430 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
7432 pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
7433 ssh2_pkt_addstring_start(pktout
);
7434 ssh2_pkt_send_noqueue(ssh
, pktout
);
7436 } else if (code
== TS_REKEY
) {
7437 if (!ssh
->kex_in_progress
&& ssh
->version
== 2) {
7438 do_ssh2_transport(ssh
, "Initiating key re-exchange at"
7439 " user request", -1, NULL
);
7441 } else if (code
== TS_BRK
) {
7442 if (ssh
->state
== SSH_STATE_CLOSED
7443 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7444 if (ssh
->version
== 1) {
7445 logevent("Unable to send BREAK signal in SSH1");
7446 } else if (ssh
->mainchan
) {
7447 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7448 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7449 ssh2_pkt_addstring(pktout
, "break");
7450 ssh2_pkt_addbool(pktout
, 0);
7451 ssh2_pkt_adduint32(pktout
, 0); /* default break length */
7452 ssh2_pkt_send(ssh
, pktout
);
7455 /* Is is a POSIX signal? */
7456 char *signame
= NULL
;
7457 if (code
== TS_SIGABRT
) signame
= "ABRT";
7458 if (code
== TS_SIGALRM
) signame
= "ALRM";
7459 if (code
== TS_SIGFPE
) signame
= "FPE";
7460 if (code
== TS_SIGHUP
) signame
= "HUP";
7461 if (code
== TS_SIGILL
) signame
= "ILL";
7462 if (code
== TS_SIGINT
) signame
= "INT";
7463 if (code
== TS_SIGKILL
) signame
= "KILL";
7464 if (code
== TS_SIGPIPE
) signame
= "PIPE";
7465 if (code
== TS_SIGQUIT
) signame
= "QUIT";
7466 if (code
== TS_SIGSEGV
) signame
= "SEGV";
7467 if (code
== TS_SIGTERM
) signame
= "TERM";
7468 if (code
== TS_SIGUSR1
) signame
= "USR1";
7469 if (code
== TS_SIGUSR2
) signame
= "USR2";
7470 /* The SSH-2 protocol does in principle support arbitrary named
7471 * signals, including signame@domain, but we don't support those. */
7473 /* It's a signal. */
7474 if (ssh
->version
== 2 && ssh
->mainchan
) {
7475 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7476 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7477 ssh2_pkt_addstring(pktout
, "signal");
7478 ssh2_pkt_addbool(pktout
, 0);
7479 ssh2_pkt_addstring(pktout
, signame
);
7480 ssh2_pkt_send(ssh
, pktout
);
7481 logeventf(ssh
, "Sent signal SIG%s", signame
);
7484 /* Never heard of it. Do nothing */
7489 void *new_sock_channel(void *handle
, Socket s
)
7491 Ssh ssh
= (Ssh
) handle
;
7492 struct ssh_channel
*c
;
7493 c
= snew(struct ssh_channel
);
7497 c
->remoteid
= -1; /* to be set when open confirmed */
7498 c
->localid
= alloc_channel_id(ssh
);
7500 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
7502 bufchain_init(&c
->v
.v2
.outbuffer
);
7503 add234(ssh
->channels
, c
);
7509 * This is called when stdout/stderr (the entity to which
7510 * from_backend sends data) manages to clear some backlog.
7512 static void ssh_unthrottle(void *handle
, int bufsize
)
7514 Ssh ssh
= (Ssh
) handle
;
7515 if (ssh
->version
== 1) {
7516 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
7517 ssh
->v1_stdout_throttling
= 0;
7518 ssh1_throttle(ssh
, -1);
7521 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
7522 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
7526 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
7528 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
7530 struct Packet
*pktout
;
7532 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
7534 if (ssh
->version
== 1) {
7535 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
7536 PKT_INT
, c
->localid
,
7539 //PKT_STR, <org:orgport>,
7542 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
7543 ssh2_pkt_addstring(pktout
, "direct-tcpip");
7544 ssh2_pkt_adduint32(pktout
, c
->localid
);
7545 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7546 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);/* our window size */
7547 ssh2_pkt_adduint32(pktout
, 0x4000UL
); /* our max pkt size */
7548 ssh2_pkt_addstring(pktout
, hostname
);
7549 ssh2_pkt_adduint32(pktout
, port
);
7551 * We make up values for the originator data; partly it's
7552 * too much hassle to keep track, and partly I'm not
7553 * convinced the server should be told details like that
7554 * about my local network configuration.
7556 ssh2_pkt_addstring(pktout
, "client-side-connection");
7557 ssh2_pkt_adduint32(pktout
, 0);
7558 ssh2_pkt_send(ssh
, pktout
);
7562 static Socket
ssh_socket(void *handle
)
7564 Ssh ssh
= (Ssh
) handle
;
7568 static int ssh_sendok(void *handle
)
7570 Ssh ssh
= (Ssh
) handle
;
7571 return ssh
->send_ok
;
7574 static int ssh_ldisc(void *handle
, int option
)
7576 Ssh ssh
= (Ssh
) handle
;
7577 if (option
== LD_ECHO
)
7578 return ssh
->echoing
;
7579 if (option
== LD_EDIT
)
7580 return ssh
->editing
;
7584 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
7586 Ssh ssh
= (Ssh
) handle
;
7590 static void ssh_provide_logctx(void *handle
, void *logctx
)
7592 Ssh ssh
= (Ssh
) handle
;
7593 ssh
->logctx
= logctx
;
7596 static int ssh_return_exitcode(void *handle
)
7598 Ssh ssh
= (Ssh
) handle
;
7602 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
7606 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
7607 * that fails. This variable is the means by which scp.c can reach
7608 * into the SSH code and find out which one it got.
7610 extern int ssh_fallback_cmd(void *handle
)
7612 Ssh ssh
= (Ssh
) handle
;
7613 return ssh
->fallback_cmd
;
7616 Backend ssh_backend
= {
7626 ssh_return_exitcode
,