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 int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
333 struct Packet
*pktin
);
334 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
335 struct Packet
*pktin
);
338 * Buffer management constants. There are several of these for
339 * various different purposes:
341 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
342 * on a local data stream before we throttle the whole SSH
343 * connection (in SSH1 only). Throttling the whole connection is
344 * pretty drastic so we set this high in the hope it won't
347 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
348 * on the SSH connection itself before we defensively throttle
349 * _all_ local data streams. This is pretty drastic too (though
350 * thankfully unlikely in SSH2 since the window mechanism should
351 * ensure that the server never has any need to throttle its end
352 * of the connection), so we set this high as well.
354 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
358 #define SSH1_BUFFER_LIMIT 32768
359 #define SSH_MAX_BACKLOG 32768
360 #define OUR_V2_WINSIZE 16384
362 const static struct ssh_kex
*kex_algs
[] = {
363 &ssh_diffiehellman_gex
,
367 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
369 static void *nullmac_make_context(void)
373 static void nullmac_free_context(void *handle
)
376 static void nullmac_key(void *handle
, unsigned char *key
)
379 static void nullmac_generate(void *handle
, unsigned char *blk
, int len
,
383 static int nullmac_verify(void *handle
, unsigned char *blk
, int len
,
388 const static struct ssh_mac ssh_mac_none
= {
389 nullmac_make_context
, nullmac_free_context
, nullmac_key
,
390 nullmac_generate
, nullmac_verify
, "none", 0
392 const static struct ssh_mac
*macs
[] = {
393 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
395 const static struct ssh_mac
*buggymacs
[] = {
396 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
399 static void *ssh_comp_none_init(void)
403 static void ssh_comp_none_cleanup(void *handle
)
406 static int ssh_comp_none_block(void *handle
, unsigned char *block
, int len
,
407 unsigned char **outblock
, int *outlen
)
411 static int ssh_comp_none_disable(void *handle
)
415 const static struct ssh_compress ssh_comp_none
= {
417 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
418 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
419 ssh_comp_none_disable
, NULL
421 extern const struct ssh_compress ssh_zlib
;
422 const static struct ssh_compress
*compressions
[] = {
423 &ssh_zlib
, &ssh_comp_none
426 enum { /* channel types */
431 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
435 * 2-3-4 tree storing channels.
438 Ssh ssh
; /* pointer back to main context */
439 unsigned remoteid
, localid
;
442 * In SSH1, this value contains four bits:
444 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
445 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
446 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
447 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
449 * A channel is completely finished with when all four bits are set.
453 struct ssh1_data_channel
{
456 struct ssh2_data_channel
{
458 unsigned remwindow
, remmaxpkt
;
463 struct ssh_agent_channel
{
464 unsigned char *message
;
465 unsigned char msglen
[4];
466 unsigned lensofar
, totallen
;
468 struct ssh_x11_channel
{
471 struct ssh_pfd_channel
{
478 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
479 * 2 use this structure in different ways, reflecting SSH 2's
480 * altogether saner approach to port forwarding.
482 * In SSH 1, you arrange a remote forwarding by sending the server
483 * the remote port number, and the local destination host:port.
484 * When a connection comes in, the server sends you back that
485 * host:port pair, and you connect to it. This is a ready-made
486 * security hole if you're not on the ball: a malicious server
487 * could send you back _any_ host:port pair, so if you trustingly
488 * connect to the address it gives you then you've just opened the
489 * entire inside of your corporate network just by connecting
490 * through it to a dodgy SSH server. Hence, we must store a list of
491 * host:port pairs we _are_ trying to forward to, and reject a
492 * connection request from the server if it's not in the list.
494 * In SSH 2, each side of the connection minds its own business and
495 * doesn't send unnecessary information to the other. You arrange a
496 * remote forwarding by sending the server just the remote port
497 * number. When a connection comes in, the server tells you which
498 * of its ports was connected to; and _you_ have to remember what
499 * local host:port pair went with that port number.
501 * Hence: in SSH 1 this structure stores host:port pairs we intend
502 * to allow connections to, and is indexed by those host:port
503 * pairs. In SSH 2 it stores a mapping from source port to
504 * destination host:port pair, and is indexed by source port.
506 struct ssh_rportfwd
{
507 unsigned sport
, dport
;
520 * State associated with packet logging
524 struct logblank_t
*blanks
;
527 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
528 struct Packet
*pktin
);
529 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
530 struct Packet
*pktin
);
531 static void ssh_size(void *handle
, int width
, int height
);
532 static void ssh_special(void *handle
, Telnet_Special
);
533 static int ssh2_try_send(struct ssh_channel
*c
);
534 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
535 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
536 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
537 static int ssh_sendbuffer(void *handle
);
538 static void ssh_do_close(Ssh ssh
);
539 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
);
540 static int ssh2_pkt_getbool(struct Packet
*pkt
);
541 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
);
543 struct rdpkt1_state_tag
{
544 long len
, pad
, biglen
, to_read
;
545 unsigned long realcrc
, gotcrc
;
549 struct Packet
*pktin
;
552 struct rdpkt2_state_tag
{
553 long len
, pad
, payload
, packetlen
, maclen
;
556 unsigned long incoming_sequence
;
557 struct Packet
*pktin
;
561 const struct plug_function_table
*fn
;
562 /* the above field _must_ be first in the structure */
564 SHA_State exhash
, exhashbase
;
571 unsigned char session_key
[32];
573 int v1_remote_protoflags
;
574 int v1_local_protoflags
;
575 int agentfwd_enabled
;
578 const struct ssh_cipher
*cipher
;
581 const struct ssh2_cipher
*cscipher
, *sccipher
;
582 void *cs_cipher_ctx
, *sc_cipher_ctx
;
583 const struct ssh_mac
*csmac
, *scmac
;
584 void *cs_mac_ctx
, *sc_mac_ctx
;
585 const struct ssh_compress
*cscomp
, *sccomp
;
586 void *cs_comp_ctx
, *sc_comp_ctx
;
587 const struct ssh_kex
*kex
;
588 const struct ssh_signkey
*hostkey
;
589 unsigned char v2_session_id
[20];
595 int echoing
, editing
;
599 int ospeed
, ispeed
; /* temporaries */
600 int term_width
, term_height
;
602 tree234
*channels
; /* indexed by local id */
603 struct ssh_channel
*mainchan
; /* primary session channel */
610 SSH_STATE_BEFORE_SIZE
,
616 int size_needed
, eof_needed
;
618 unsigned char *deferred_send_data
;
619 int deferred_len
, deferred_size
;
622 * Gross hack: pscp will try to start SFTP but fall back to
623 * scp1 if that fails. This variable is the means by which
624 * scp.c can reach into the SSH code and find out which one it
630 * Used for username and password input.
632 char *userpass_input_buffer
;
633 int userpass_input_buflen
;
634 int userpass_input_bufpos
;
635 int userpass_input_echo
;
637 char *portfwd_strptr
;
643 int v1_throttle_count
;
646 int v1_stdout_throttling
;
647 int v2_outgoing_sequence
;
649 int ssh1_rdpkt_crstate
;
650 int ssh2_rdpkt_crstate
;
651 int do_ssh_init_crstate
;
652 int ssh_gotdata_crstate
;
653 int ssh1_protocol_crstate
;
654 int do_ssh1_login_crstate
;
655 int do_ssh2_transport_crstate
;
656 int do_ssh2_authconn_crstate
;
658 void *do_ssh_init_state
;
659 void *do_ssh1_login_state
;
660 void *do_ssh2_transport_state
;
661 void *do_ssh2_authconn_state
;
663 struct rdpkt1_state_tag rdpkt1_state
;
664 struct rdpkt2_state_tag rdpkt2_state
;
666 void (*protocol
) (Ssh ssh
, unsigned char *in
, int inlen
,
668 struct Packet
*(*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
671 * We maintain a full _copy_ of a Config structure here, not
672 * merely a pointer to it. That way, when we're passed a new
673 * one for reconfiguration, we can check the differences and
674 * potentially reconfigure port forwardings etc in mid-session.
679 * Used to transfer data back from async agent callbacks.
681 void *agent_response
;
682 int agent_response_len
;
685 #define logevent(s) logevent(ssh->frontend, s)
687 /* logevent, only printf-formatted. */
688 static void logeventf(Ssh ssh
, const char *fmt
, ...)
694 buf
= dupvprintf(fmt
, ap
);
700 #define bombout(msg) \
702 char *text = dupprintf msg; \
705 connection_fatal(ssh->frontend, "%s", text); \
709 /* Functions to leave bits out of the SSH packet log file. */
711 static void dont_log_password(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
713 if (ssh
->cfg
.logomitpass
)
714 pkt
->logmode
= blanktype
;
717 static void dont_log_data(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
719 if (ssh
->cfg
.logomitdata
)
720 pkt
->logmode
= blanktype
;
723 static void end_log_omission(Ssh ssh
, struct Packet
*pkt
)
725 pkt
->logmode
= PKTLOG_EMIT
;
728 static int ssh_channelcmp(void *av
, void *bv
)
730 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
731 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
732 if (a
->localid
< b
->localid
)
734 if (a
->localid
> b
->localid
)
738 static int ssh_channelfind(void *av
, void *bv
)
740 unsigned *a
= (unsigned *) av
;
741 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
749 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
751 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
752 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
754 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
755 return i
< 0 ?
-1 : +1;
756 if (a
->dport
> b
->dport
)
758 if (a
->dport
< b
->dport
)
763 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
765 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
766 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
768 if (a
->sport
> b
->sport
)
770 if (a
->sport
< b
->sport
)
775 static int alloc_channel_id(Ssh ssh
)
777 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
778 unsigned low
, high
, mid
;
780 struct ssh_channel
*c
;
783 * First-fit allocation of channel numbers: always pick the
784 * lowest unused one. To do this, binary-search using the
785 * counted B-tree to find the largest channel ID which is in a
786 * contiguous sequence from the beginning. (Precisely
787 * everything in that sequence must have ID equal to its tree
788 * index plus CHANNEL_NUMBER_OFFSET.)
790 tsize
= count234(ssh
->channels
);
794 while (high
- low
> 1) {
795 mid
= (high
+ low
) / 2;
796 c
= index234(ssh
->channels
, mid
);
797 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
798 low
= mid
; /* this one is fine */
800 high
= mid
; /* this one is past it */
803 * Now low points to either -1, or the tree index of the
804 * largest ID in the initial sequence.
807 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
808 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
810 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
813 static void c_write(Ssh ssh
, const char *buf
, int len
)
815 if ((flags
& FLAG_STDERR
)) {
817 for (i
= 0; i
< len
; i
++)
819 fputc(buf
[i
], stderr
);
822 from_backend(ssh
->frontend
, 1, buf
, len
);
825 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
828 for (i
= 0; i
< len
; i
++) {
830 c_write(ssh
, "\r\n", 2);
831 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
832 c_write(ssh
, buf
+ i
, 1);
836 static void c_write_str(Ssh ssh
, const char *buf
)
838 c_write(ssh
, buf
, strlen(buf
));
841 static void ssh_free_packet(struct Packet
*pkt
)
846 static struct Packet
*ssh_new_packet(void)
848 struct Packet
*pkt
= snew(struct Packet
);
852 pkt
->logmode
= PKTLOG_EMIT
;
860 * Collect incoming data in the incoming packet buffer.
861 * Decipher and verify the packet when it is completely read.
862 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
863 * Update the *data and *datalen variables.
864 * Return a Packet structure when a packet is completed.
866 static struct Packet
*ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
868 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
870 crBegin(ssh
->ssh1_rdpkt_crstate
);
874 st
->pktin
= ssh_new_packet();
877 st
->pktin
->length
= 0;
879 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
880 while ((*datalen
) == 0)
882 st
->len
= (st
->len
<< 8) + **data
;
883 (*data
)++, (*datalen
)--;
886 st
->pad
= 8 - (st
->len
% 8);
887 st
->biglen
= st
->len
+ st
->pad
;
888 st
->pktin
->length
= st
->len
- 5;
890 if (st
->biglen
< 0) {
891 bombout(("Extremely large packet length from server suggests"
892 " data stream corruption"));
893 ssh_free_packet(st
->pktin
);
897 st
->pktin
->maxlen
= st
->biglen
;
898 st
->pktin
->data
= snewn(st
->biglen
+ APIEXTRA
, unsigned char);
900 st
->to_read
= st
->biglen
;
901 st
->p
= st
->pktin
->data
;
902 while (st
->to_read
> 0) {
903 st
->chunk
= st
->to_read
;
904 while ((*datalen
) == 0)
906 if (st
->chunk
> (*datalen
))
907 st
->chunk
= (*datalen
);
908 memcpy(st
->p
, *data
, st
->chunk
);
910 *datalen
-= st
->chunk
;
912 st
->to_read
-= st
->chunk
;
915 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, st
->pktin
->data
,
917 bombout(("Network attack (CRC compensation) detected!"));
918 ssh_free_packet(st
->pktin
);
923 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, st
->pktin
->data
, st
->biglen
);
925 st
->realcrc
= crc32_compute(st
->pktin
->data
, st
->biglen
- 4);
926 st
->gotcrc
= GET_32BIT(st
->pktin
->data
+ st
->biglen
- 4);
927 if (st
->gotcrc
!= st
->realcrc
) {
928 bombout(("Incorrect CRC received on packet"));
929 ssh_free_packet(st
->pktin
);
933 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
934 st
->pktin
->savedpos
= 0;
936 if (ssh
->v1_compressing
) {
937 unsigned char *decompblk
;
939 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
940 st
->pktin
->body
- 1, st
->pktin
->length
+ 1,
941 &decompblk
, &decomplen
)) {
942 bombout(("Zlib decompression encountered invalid data"));
943 ssh_free_packet(st
->pktin
);
947 if (st
->pktin
->maxlen
< st
->pad
+ decomplen
) {
948 st
->pktin
->maxlen
= st
->pad
+ decomplen
;
949 st
->pktin
->data
= sresize(st
->pktin
->data
,
950 st
->pktin
->maxlen
+ APIEXTRA
,
952 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
955 memcpy(st
->pktin
->body
- 1, decompblk
, decomplen
);
957 st
->pktin
->length
= decomplen
- 1;
960 st
->pktin
->type
= st
->pktin
->body
[-1];
963 * Log incoming packet, possibly omitting sensitive fields.
967 struct logblank_t blank
;
968 if (ssh
->cfg
.logomitdata
) {
969 int do_blank
= FALSE
, blank_prefix
= 0;
970 /* "Session data" packets - omit the data field */
971 if ((st
->pktin
->type
== SSH1_SMSG_STDOUT_DATA
) ||
972 (st
->pktin
->type
== SSH1_SMSG_STDERR_DATA
)) {
973 do_blank
= TRUE
; blank_prefix
= 0;
974 } else if (st
->pktin
->type
== SSH1_MSG_CHANNEL_DATA
) {
975 do_blank
= TRUE
; blank_prefix
= 4;
978 blank
.offset
= blank_prefix
;
979 blank
.len
= st
->pktin
->length
;
980 blank
.type
= PKTLOG_OMIT
;
984 log_packet(ssh
->logctx
,
985 PKT_INCOMING
, st
->pktin
->type
,
986 ssh1_pkt_type(st
->pktin
->type
),
987 st
->pktin
->body
, st
->pktin
->length
,
991 if (st
->pktin
->type
== SSH1_SMSG_STDOUT_DATA
||
992 st
->pktin
->type
== SSH1_SMSG_STDERR_DATA
||
993 st
->pktin
->type
== SSH1_MSG_DEBUG
||
994 st
->pktin
->type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
995 st
->pktin
->type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
996 long stringlen
= GET_32BIT(st
->pktin
->body
);
997 if (stringlen
+ 4 != st
->pktin
->length
) {
998 bombout(("Received data packet with bogus string length"));
999 ssh_free_packet(st
->pktin
);
1004 if (st
->pktin
->type
== SSH1_MSG_DEBUG
) {
1008 ssh_pkt_getstring(st
->pktin
, &msg
, &msglen
);
1009 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
1013 ssh_free_packet(st
->pktin
);
1015 } else if (st
->pktin
->type
== SSH1_MSG_IGNORE
) {
1017 ssh_free_packet(st
->pktin
);
1021 if (st
->pktin
->type
== SSH1_MSG_DISCONNECT
) {
1022 /* log reason code in disconnect message */
1026 ssh_pkt_getstring(st
->pktin
, &msg
, &msglen
);
1028 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen
, msg
));
1029 ssh_free_packet(st
->pktin
);
1033 crFinish(st
->pktin
);
1036 static struct Packet
*ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1038 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1040 crBegin(ssh
->ssh2_rdpkt_crstate
);
1044 st
->pktin
= ssh_new_packet();
1046 st
->pktin
->type
= 0;
1047 st
->pktin
->length
= 0;
1049 st
->cipherblk
= ssh
->sccipher
->blksize
;
1052 if (st
->cipherblk
< 8)
1055 st
->pktin
->data
= snewn(st
->cipherblk
+ APIEXTRA
, unsigned char);
1058 * Acquire and decrypt the first block of the packet. This will
1059 * contain the length and padding details.
1061 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1062 while ((*datalen
) == 0)
1064 st
->pktin
->data
[st
->i
] = *(*data
)++;
1069 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1070 st
->pktin
->data
, st
->cipherblk
);
1073 * Now get the length and padding figures.
1075 st
->len
= GET_32BIT(st
->pktin
->data
);
1076 st
->pad
= st
->pktin
->data
[4];
1079 * _Completely_ silly lengths should be stomped on before they
1080 * do us any more damage.
1082 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
1083 bombout(("Incoming packet was garbled on decryption"));
1084 ssh_free_packet(st
->pktin
);
1089 * This enables us to deduce the payload length.
1091 st
->payload
= st
->len
- st
->pad
- 1;
1093 st
->pktin
->length
= st
->payload
+ 5;
1096 * So now we can work out the total packet length.
1098 st
->packetlen
= st
->len
+ 4;
1099 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1102 * Allocate memory for the rest of the packet.
1104 st
->pktin
->maxlen
= st
->packetlen
+ st
->maclen
;
1105 st
->pktin
->data
= sresize(st
->pktin
->data
,
1106 st
->pktin
->maxlen
+ APIEXTRA
,
1110 * Read and decrypt the remainder of the packet.
1112 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1114 while ((*datalen
) == 0)
1116 st
->pktin
->data
[st
->i
] = *(*data
)++;
1119 /* Decrypt everything _except_ the MAC. */
1121 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1122 st
->pktin
->data
+ st
->cipherblk
,
1123 st
->packetlen
- st
->cipherblk
);
1129 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, st
->pktin
->data
, st
->len
+ 4,
1130 st
->incoming_sequence
)) {
1131 bombout(("Incorrect MAC received on packet"));
1132 ssh_free_packet(st
->pktin
);
1135 st
->incoming_sequence
++; /* whether or not we MACed */
1138 * Decompress packet payload.
1141 unsigned char *newpayload
;
1144 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1145 st
->pktin
->data
+ 5, st
->pktin
->length
- 5,
1146 &newpayload
, &newlen
)) {
1147 if (st
->pktin
->maxlen
< newlen
+ 5) {
1148 st
->pktin
->maxlen
= newlen
+ 5;
1149 st
->pktin
->data
= sresize(st
->pktin
->data
,
1150 st
->pktin
->maxlen
+ APIEXTRA
,
1153 st
->pktin
->length
= 5 + newlen
;
1154 memcpy(st
->pktin
->data
+ 5, newpayload
, newlen
);
1159 st
->pktin
->savedpos
= 6;
1160 st
->pktin
->body
= st
->pktin
->data
;
1161 st
->pktin
->type
= st
->pktin
->data
[5];
1164 * Log incoming packet, possibly omitting sensitive fields.
1168 struct logblank_t blank
;
1169 if (ssh
->cfg
.logomitdata
) {
1170 int do_blank
= FALSE
, blank_prefix
= 0;
1171 /* "Session data" packets - omit the data field */
1172 if (st
->pktin
->type
== SSH2_MSG_CHANNEL_DATA
) {
1173 do_blank
= TRUE
; blank_prefix
= 4;
1174 } else if (st
->pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1175 do_blank
= TRUE
; blank_prefix
= 8;
1178 blank
.offset
= blank_prefix
;
1179 blank
.len
= (st
->pktin
->length
-6) - blank_prefix
;
1180 blank
.type
= PKTLOG_OMIT
;
1184 log_packet(ssh
->logctx
, PKT_INCOMING
, st
->pktin
->type
,
1185 ssh2_pkt_type(ssh
->pkt_ctx
, st
->pktin
->type
),
1186 st
->pktin
->data
+6, st
->pktin
->length
-6,
1190 switch (st
->pktin
->type
) {
1192 * These packets we must handle instantly.
1194 case SSH2_MSG_DISCONNECT
:
1196 /* log reason code in disconnect message */
1198 int nowlen
, reason
, msglen
;
1200 reason
= ssh_pkt_getuint32(st
->pktin
);
1201 ssh_pkt_getstring(st
->pktin
, &msg
, &msglen
);
1203 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
1204 buf
= dupprintf("Received disconnect message (%s)",
1205 ssh2_disconnect_reasons
[reason
]);
1207 buf
= dupprintf("Received disconnect message (unknown"
1208 " type %d)", reason
);
1212 buf
= dupprintf("Disconnection message text: %n%.*s",
1213 &nowlen
, msglen
, msg
);
1215 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
1217 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
1218 ssh2_disconnect_reasons
[reason
] : "unknown",
1221 ssh_free_packet(st
->pktin
);
1225 case SSH2_MSG_IGNORE
:
1226 ssh_free_packet(st
->pktin
);
1228 case SSH2_MSG_DEBUG
:
1230 /* log the debug message */
1235 /* XXX maybe we should actually take notice of this */
1236 always_display
= ssh2_pkt_getbool(st
->pktin
);
1237 ssh_pkt_getstring(st
->pktin
, &msg
, &msglen
);
1239 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
1243 ssh_free_packet(st
->pktin
);
1247 * These packets we need do nothing about here.
1249 case SSH2_MSG_UNIMPLEMENTED
:
1250 case SSH2_MSG_SERVICE_REQUEST
:
1251 case SSH2_MSG_SERVICE_ACCEPT
:
1252 case SSH2_MSG_KEXINIT
:
1253 case SSH2_MSG_NEWKEYS
:
1254 case SSH2_MSG_KEXDH_INIT
:
1255 case SSH2_MSG_KEXDH_REPLY
:
1256 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1257 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1258 case SSH2_MSG_KEX_DH_GEX_INIT
:
1259 case SSH2_MSG_KEX_DH_GEX_REPLY
:
1260 case SSH2_MSG_USERAUTH_REQUEST
:
1261 case SSH2_MSG_USERAUTH_FAILURE
:
1262 case SSH2_MSG_USERAUTH_SUCCESS
:
1263 case SSH2_MSG_USERAUTH_BANNER
:
1264 case SSH2_MSG_USERAUTH_PK_OK
:
1265 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1266 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1267 case SSH2_MSG_USERAUTH_INFO_RESPONSE
:
1268 case SSH2_MSG_GLOBAL_REQUEST
:
1269 case SSH2_MSG_REQUEST_SUCCESS
:
1270 case SSH2_MSG_REQUEST_FAILURE
:
1271 case SSH2_MSG_CHANNEL_OPEN
:
1272 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
:
1273 case SSH2_MSG_CHANNEL_OPEN_FAILURE
:
1274 case SSH2_MSG_CHANNEL_WINDOW_ADJUST
:
1275 case SSH2_MSG_CHANNEL_DATA
:
1276 case SSH2_MSG_CHANNEL_EXTENDED_DATA
:
1277 case SSH2_MSG_CHANNEL_EOF
:
1278 case SSH2_MSG_CHANNEL_CLOSE
:
1279 case SSH2_MSG_CHANNEL_REQUEST
:
1280 case SSH2_MSG_CHANNEL_SUCCESS
:
1281 case SSH2_MSG_CHANNEL_FAILURE
:
1285 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1289 struct Packet
*pktout
;
1290 pktout
= ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
1291 ssh2_pkt_adduint32(pktout
, st
->incoming_sequence
- 1);
1292 ssh2_pkt_send(ssh
, pktout
);
1297 crFinish(st
->pktin
);
1300 static void ssh1_pktout_size(struct Packet
*pkt
, int len
)
1304 len
+= 5; /* type and CRC */
1305 pad
= 8 - (len
% 8);
1308 pkt
->length
= len
- 5;
1309 if (pkt
->maxlen
< biglen
) {
1310 pkt
->maxlen
= biglen
;
1311 pkt
->data
= sresize(pkt
->data
, biglen
+ 4 + APIEXTRA
, unsigned char);
1313 pkt
->body
= pkt
->data
+ 4 + pad
+ 1;
1316 static struct Packet
*s_wrpkt_start(int type
, int len
)
1318 struct Packet
*pkt
= ssh_new_packet();
1319 ssh1_pktout_size(pkt
, len
);
1321 /* Initialise log omission state */
1327 static int s_wrpkt_prepare(Ssh ssh
, struct Packet
*pkt
)
1333 * XXX various versions of SC (including 8.8.4) screw up the
1334 * register allocation in this function and use the same register
1335 * (D6) for len and as a temporary, with predictable results. The
1336 * following sledgehammer prevents this.
1342 pkt
->body
[-1] = pkt
->type
;
1345 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->type
,
1346 ssh1_pkt_type(pkt
->type
),
1347 pkt
->body
, pkt
->length
,
1348 pkt
->nblanks
, pkt
->blanks
);
1349 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1352 if (ssh
->v1_compressing
) {
1353 unsigned char *compblk
;
1355 zlib_compress_block(ssh
->cs_comp_ctx
,
1356 pkt
->body
- 1, pkt
->length
+ 1,
1357 &compblk
, &complen
);
1358 ssh1_pktout_size(pkt
, complen
- 1);
1359 memcpy(pkt
->body
- 1, compblk
, complen
);
1363 len
= pkt
->length
+ 5; /* type and CRC */
1364 pad
= 8 - (len
% 8);
1367 for (i
= 0; i
< pad
; i
++)
1368 pkt
->data
[i
+ 4] = random_byte();
1369 crc
= crc32_compute(pkt
->data
+ 4, biglen
- 4);
1370 PUT_32BIT(pkt
->data
+ biglen
, crc
);
1371 PUT_32BIT(pkt
->data
, len
);
1374 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, pkt
->data
+ 4, biglen
);
1379 static void s_wrpkt(Ssh ssh
, struct Packet
*pkt
)
1382 len
= s_wrpkt_prepare(ssh
, pkt
);
1383 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1384 if (backlog
> SSH_MAX_BACKLOG
)
1385 ssh_throttle_all(ssh
, 1, backlog
);
1388 static void s_wrpkt_defer(Ssh ssh
, struct Packet
*pkt
)
1391 len
= s_wrpkt_prepare(ssh
, pkt
);
1392 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1393 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1394 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1398 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1399 ssh
->deferred_len
+= len
;
1403 * Construct a packet with the specified contents.
1405 static struct Packet
*construct_packet(Ssh ssh
, int pkttype
,
1406 va_list ap1
, va_list ap2
)
1408 unsigned char *p
, *argp
, argchar
;
1409 unsigned long argint
;
1410 int pktlen
, argtype
, arglen
;
1415 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1418 (void) va_arg(ap1
, int);
1422 (void) va_arg(ap1
, int);
1426 (void) va_arg(ap1
, unsigned char *);
1427 arglen
= va_arg(ap1
, int);
1431 argp
= va_arg(ap1
, unsigned char *);
1432 arglen
= strlen((char *)argp
);
1433 pktlen
+= 4 + arglen
;
1436 bn
= va_arg(ap1
, Bignum
);
1437 pktlen
+= ssh1_bignum_length(bn
);
1442 /* ignore this pass */
1449 pkt
= s_wrpkt_start(pkttype
, pktlen
);
1452 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1453 int offset
= p
- pkt
->body
, len
= 0;
1455 /* Actual fields in the packet */
1457 argint
= va_arg(ap2
, int);
1458 PUT_32BIT(p
, argint
);
1462 argchar
= (unsigned char) va_arg(ap2
, int);
1467 argp
= va_arg(ap2
, unsigned char *);
1468 arglen
= va_arg(ap2
, int);
1469 memcpy(p
, argp
, arglen
);
1473 argp
= va_arg(ap2
, unsigned char *);
1474 arglen
= strlen((char *)argp
);
1475 PUT_32BIT(p
, arglen
);
1476 memcpy(p
+ 4, argp
, arglen
);
1480 bn
= va_arg(ap2
, Bignum
);
1481 len
= ssh1_write_bignum(p
, bn
);
1483 /* Tokens for modifications to packet logging */
1485 dont_log_password(ssh
, pkt
, PKTLOG_BLANK
);
1488 dont_log_data(ssh
, pkt
, PKTLOG_OMIT
);
1491 end_log_omission(ssh
, pkt
);
1495 /* Deal with logfile omission, if required. */
1496 if (len
&& (pkt
->logmode
!= PKTLOG_EMIT
)) {
1498 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
,
1500 pkt
->blanks
[pkt
->nblanks
-1].offset
= offset
;
1501 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1502 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1509 static void send_packet(Ssh ssh
, int pkttype
, ...)
1513 va_start(ap1
, pkttype
);
1514 va_start(ap2
, pkttype
);
1515 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1519 ssh_free_packet(pkt
);
1522 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1526 va_start(ap1
, pkttype
);
1527 va_start(ap2
, pkttype
);
1528 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1531 s_wrpkt_defer(ssh
, pkt
);
1532 ssh_free_packet(pkt
);
1535 static int ssh_versioncmp(char *a
, char *b
)
1538 unsigned long av
, bv
;
1540 av
= strtoul(a
, &ae
, 10);
1541 bv
= strtoul(b
, &be
, 10);
1543 return (av
< bv ?
-1 : +1);
1548 av
= strtoul(ae
, &ae
, 10);
1549 bv
= strtoul(be
, &be
, 10);
1551 return (av
< bv ?
-1 : +1);
1556 * Utility routines for putting an SSH-protocol `string' and
1557 * `uint32' into a SHA state.
1560 static void sha_string(SHA_State
* s
, void *str
, int len
)
1562 unsigned char lenblk
[4];
1563 PUT_32BIT(lenblk
, len
);
1564 SHA_Bytes(s
, lenblk
, 4);
1565 SHA_Bytes(s
, str
, len
);
1568 static void sha_uint32(SHA_State
* s
, unsigned i
)
1570 unsigned char intblk
[4];
1571 PUT_32BIT(intblk
, i
);
1572 SHA_Bytes(s
, intblk
, 4);
1576 * SSH2 packet construction functions.
1578 static void ssh2_pkt_ensure(struct Packet
*pkt
, int length
)
1580 if (pkt
->maxlen
< length
) {
1581 pkt
->maxlen
= length
+ 256;
1582 pkt
->data
= sresize(pkt
->data
, pkt
->maxlen
+ APIEXTRA
, unsigned char);
1585 static void ssh2_pkt_adddata(struct Packet
*pkt
, void *data
, int len
)
1587 if (pkt
->logmode
!= PKTLOG_EMIT
) {
1589 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
, struct logblank_t
);
1590 pkt
->blanks
[pkt
->nblanks
-1].offset
= pkt
->length
- 6;
1591 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1592 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1595 ssh2_pkt_ensure(pkt
, pkt
->length
);
1596 memcpy(pkt
->data
+ pkt
->length
- len
, data
, len
);
1598 static void ssh2_pkt_addbyte(struct Packet
*pkt
, unsigned char byte
)
1600 ssh2_pkt_adddata(pkt
, &byte
, 1);
1602 static struct Packet
*ssh2_pkt_init(int pkt_type
)
1604 struct Packet
*pkt
= ssh_new_packet();
1606 ssh2_pkt_addbyte(pkt
, (unsigned char) pkt_type
);
1609 static void ssh2_pkt_addbool(struct Packet
*pkt
, unsigned char value
)
1611 ssh2_pkt_adddata(pkt
, &value
, 1);
1613 static void ssh2_pkt_adduint32(struct Packet
*pkt
, unsigned long value
)
1616 PUT_32BIT(x
, value
);
1617 ssh2_pkt_adddata(pkt
, x
, 4);
1619 static void ssh2_pkt_addstring_start(struct Packet
*pkt
)
1621 ssh2_pkt_adduint32(pkt
, 0);
1622 pkt
->savedpos
= pkt
->length
;
1624 static void ssh2_pkt_addstring_str(struct Packet
*pkt
, char *data
)
1626 ssh2_pkt_adddata(pkt
, data
, strlen(data
));
1627 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1629 static void ssh2_pkt_addstring_data(struct Packet
*pkt
, char *data
, int len
)
1631 ssh2_pkt_adddata(pkt
, data
, len
);
1632 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1634 static void ssh2_pkt_addstring(struct Packet
*pkt
, char *data
)
1636 ssh2_pkt_addstring_start(pkt
);
1637 ssh2_pkt_addstring_str(pkt
, data
);
1639 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1642 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1643 p
= snewn(n
+ 1, unsigned char);
1645 fatalbox("out of memory");
1647 for (i
= 1; i
<= n
; i
++)
1648 p
[i
] = bignum_byte(b
, n
- i
);
1650 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1652 memmove(p
, p
+ i
, n
+ 1 - i
);
1656 static void ssh2_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1660 p
= ssh2_mpint_fmt(b
, &len
);
1661 ssh2_pkt_addstring_start(pkt
);
1662 ssh2_pkt_addstring_data(pkt
, (char *)p
, len
);
1667 * Construct an SSH2 final-form packet: compress it, encrypt it,
1668 * put the MAC on it. Final packet, ready to be sent, is stored in
1669 * pkt->data. Total length is returned.
1671 static int ssh2_pkt_construct(Ssh ssh
, struct Packet
*pkt
)
1673 int cipherblk
, maclen
, padding
, i
;
1676 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[5],
1677 ssh2_pkt_type(ssh
->pkt_ctx
, pkt
->data
[5]),
1678 pkt
->data
+ 6, pkt
->length
- 6,
1679 pkt
->nblanks
, pkt
->blanks
);
1680 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1684 * Compress packet payload.
1687 unsigned char *newpayload
;
1690 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, pkt
->data
+ 5,
1692 &newpayload
, &newlen
)) {
1694 ssh2_pkt_adddata(pkt
, newpayload
, newlen
);
1700 * Add padding. At least four bytes, and must also bring total
1701 * length (minus MAC) up to a multiple of the block size.
1703 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1704 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1707 (cipherblk
- (pkt
->length
+ padding
) % cipherblk
) % cipherblk
;
1708 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1709 ssh2_pkt_ensure(pkt
, pkt
->length
+ padding
+ maclen
);
1710 pkt
->data
[4] = padding
;
1711 for (i
= 0; i
< padding
; i
++)
1712 pkt
->data
[pkt
->length
+ i
] = random_byte();
1713 PUT_32BIT(pkt
->data
, pkt
->length
+ padding
- 4);
1715 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, pkt
->data
,
1716 pkt
->length
+ padding
,
1717 ssh
->v2_outgoing_sequence
);
1718 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1721 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1722 pkt
->data
, pkt
->length
+ padding
);
1724 /* Ready-to-send packet starts at pkt->data. We return length. */
1725 return pkt
->length
+ padding
+ maclen
;
1729 * Construct and send an SSH2 packet immediately.
1731 static void ssh2_pkt_send(Ssh ssh
, struct Packet
*pkt
)
1735 len
= ssh2_pkt_construct(ssh
, pkt
);
1736 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1737 if (backlog
> SSH_MAX_BACKLOG
)
1738 ssh_throttle_all(ssh
, 1, backlog
);
1739 ssh_free_packet(pkt
);
1743 * Construct an SSH2 packet and add it to a deferred data block.
1744 * Useful for sending multiple packets in a single sk_write() call,
1745 * to prevent a traffic-analysing listener from being able to work
1746 * out the length of any particular packet (such as the password
1749 * Note that because SSH2 sequence-numbers its packets, this can
1750 * NOT be used as an m4-style `defer' allowing packets to be
1751 * constructed in one order and sent in another.
1753 static void ssh2_pkt_defer(Ssh ssh
, struct Packet
*pkt
)
1755 int len
= ssh2_pkt_construct(ssh
, pkt
);
1756 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1757 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1758 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1762 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1763 ssh
->deferred_len
+= len
;
1764 ssh_free_packet(pkt
);
1768 * Send the whole deferred data block constructed by
1769 * ssh2_pkt_defer() or SSH1's defer_packet().
1771 static void ssh_pkt_defersend(Ssh ssh
)
1774 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1776 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1777 sfree(ssh
->deferred_send_data
);
1778 ssh
->deferred_send_data
= NULL
;
1779 if (backlog
> SSH_MAX_BACKLOG
)
1780 ssh_throttle_all(ssh
, 1, backlog
);
1784 void bndebug(char *string
, Bignum b
)
1788 p
= ssh2_mpint_fmt(b
, &len
);
1789 debug(("%s", string
));
1790 for (i
= 0; i
< len
; i
++)
1791 debug((" %02x", p
[i
]));
1797 static void sha_mpint(SHA_State
* s
, Bignum b
)
1801 p
= ssh2_mpint_fmt(b
, &len
);
1802 sha_string(s
, p
, len
);
1807 * Packet decode functions for both SSH1 and SSH2.
1809 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
)
1811 unsigned long value
;
1812 if (pkt
->length
- pkt
->savedpos
< 4)
1813 return 0; /* arrgh, no way to decline (FIXME?) */
1814 value
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1818 static int ssh2_pkt_getbool(struct Packet
*pkt
)
1820 unsigned long value
;
1821 if (pkt
->length
- pkt
->savedpos
< 1)
1822 return 0; /* arrgh, no way to decline (FIXME?) */
1823 value
= pkt
->body
[pkt
->savedpos
] != 0;
1827 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
)
1832 if (pkt
->length
- pkt
->savedpos
< 4)
1834 len
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1839 if (pkt
->length
- pkt
->savedpos
< *length
)
1841 *p
= (char *)(pkt
->body
+ pkt
->savedpos
);
1842 pkt
->savedpos
+= *length
;
1844 static void *ssh_pkt_getdata(struct Packet
*pkt
, int length
)
1846 if (pkt
->length
- pkt
->savedpos
< length
)
1848 pkt
->savedpos
+= length
;
1849 return pkt
->body
+ (pkt
->savedpos
- length
);
1851 static int ssh1_pkt_getrsakey(struct Packet
*pkt
, struct RSAKey
*key
,
1852 unsigned char **keystr
)
1856 j
= makekey(pkt
->body
+ pkt
->savedpos
,
1857 pkt
->length
- pkt
->savedpos
,
1864 assert(pkt
->savedpos
< pkt
->length
);
1868 static Bignum
ssh1_pkt_getmp(struct Packet
*pkt
)
1873 j
= ssh1_read_bignum(pkt
->body
+ pkt
->savedpos
,
1874 pkt
->length
- pkt
->savedpos
, &b
);
1882 static Bignum
ssh2_pkt_getmp(struct Packet
*pkt
)
1888 ssh_pkt_getstring(pkt
, &p
, &length
);
1893 b
= bignum_from_bytes((unsigned char *)p
, length
);
1898 * Helper function to add an SSH2 signature blob to a packet.
1899 * Expects to be shown the public key blob as well as the signature
1900 * blob. Normally works just like ssh2_pkt_addstring, but will
1901 * fiddle with the signature packet if necessary for
1902 * BUG_SSH2_RSA_PADDING.
1904 static void ssh2_add_sigblob(Ssh ssh
, struct Packet
*pkt
,
1905 void *pkblob_v
, int pkblob_len
,
1906 void *sigblob_v
, int sigblob_len
)
1908 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1909 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1911 /* dmemdump(pkblob, pkblob_len); */
1912 /* dmemdump(sigblob, sigblob_len); */
1915 * See if this is in fact an ssh-rsa signature and a buggy
1916 * server; otherwise we can just do this the easy way.
1918 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1919 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1920 int pos
, len
, siglen
;
1923 * Find the byte length of the modulus.
1926 pos
= 4+7; /* skip over "ssh-rsa" */
1927 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1928 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
1929 pos
+= 4; /* find modulus itself */
1930 while (len
> 0 && pkblob
[pos
] == 0)
1932 /* debug(("modulus length is %d\n", len)); */
1935 * Now find the signature integer.
1937 pos
= 4+7; /* skip over "ssh-rsa" */
1938 siglen
= GET_32BIT(sigblob
+pos
);
1939 /* debug(("signature length is %d\n", siglen)); */
1941 if (len
!= siglen
) {
1942 unsigned char newlen
[4];
1943 ssh2_pkt_addstring_start(pkt
);
1944 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, pos
);
1945 /* dmemdump(sigblob, pos); */
1946 pos
+= 4; /* point to start of actual sig */
1947 PUT_32BIT(newlen
, len
);
1948 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 4);
1949 /* dmemdump(newlen, 4); */
1951 while (len
-- > siglen
) {
1952 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 1);
1953 /* dmemdump(newlen, 1); */
1955 ssh2_pkt_addstring_data(pkt
, (char *)(sigblob
+pos
), siglen
);
1956 /* dmemdump(sigblob+pos, siglen); */
1960 /* Otherwise fall through and do it the easy way. */
1963 ssh2_pkt_addstring_start(pkt
);
1964 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, sigblob_len
);
1968 * Examine the remote side's version string and compare it against
1969 * a list of known buggy implementations.
1971 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
1973 char *imp
; /* pointer to implementation part */
1975 imp
+= strcspn(imp
, "-");
1977 imp
+= strcspn(imp
, "-");
1980 ssh
->remote_bugs
= 0;
1982 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
1983 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
1984 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
1985 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
1986 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
1987 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
1989 * These versions don't support SSH1_MSG_IGNORE, so we have
1990 * to use a different defence against password length
1993 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
1994 logevent("We believe remote version has SSH1 ignore bug");
1997 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
1998 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
1999 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
2001 * These versions need a plain password sent; they can't
2002 * handle having a null and a random length of data after
2005 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
2006 logevent("We believe remote version needs a plain SSH1 password");
2009 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
2010 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
2011 (!strcmp(imp
, "Cisco-1.25")))) {
2013 * These versions apparently have no clue whatever about
2014 * RSA authentication and will panic and die if they see
2015 * an AUTH_RSA message.
2017 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
2018 logevent("We believe remote version can't handle RSA authentication");
2021 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
2022 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
2023 !wc_match("* VShell", imp
) &&
2024 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
2025 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
2026 wc_match("2.1 *", imp
)))) {
2028 * These versions have the HMAC bug.
2030 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
2031 logevent("We believe remote version has SSH2 HMAC bug");
2034 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2035 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2036 !wc_match("* VShell", imp
) &&
2037 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2039 * These versions have the key-derivation bug (failing to
2040 * include the literal shared secret in the hashes that
2041 * generate the keys).
2043 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2044 logevent("We believe remote version has SSH2 key-derivation bug");
2047 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2048 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2049 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2050 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2052 * These versions have the SSH2 RSA padding bug.
2054 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2055 logevent("We believe remote version has SSH2 RSA padding bug");
2058 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2059 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2060 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2062 * These versions have the SSH2 session-ID bug in
2063 * public-key authentication.
2065 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2066 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2069 if (ssh
->cfg
.sshbug_dhgex2
== FORCE_ON
) {
2071 * User specified the SSH2 DH GEX bug.
2073 ssh
->remote_bugs
|= BUG_SSH2_DH_GEX
;
2074 logevent("We believe remote version has SSH2 DH group exchange bug");
2078 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2080 struct do_ssh_init_state
{
2088 crState(do_ssh_init_state
);
2090 crBegin(ssh
->do_ssh_init_crstate
);
2092 /* Search for the string "SSH-" in the input. */
2095 static const int transS
[] = { 1, 2, 2, 1 };
2096 static const int transH
[] = { 0, 0, 3, 0 };
2097 static const int transminus
[] = { 0, 0, 0, -1 };
2099 s
->i
= transS
[s
->i
];
2101 s
->i
= transH
[s
->i
];
2103 s
->i
= transminus
[s
->i
];
2108 crReturn(1); /* get another character */
2112 s
->vstring
= snewn(s
->vstrsize
, char);
2113 strcpy(s
->vstring
, "SSH-");
2117 crReturn(1); /* get another char */
2118 if (s
->vslen
>= s
->vstrsize
- 1) {
2120 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2122 s
->vstring
[s
->vslen
++] = c
;
2125 s
->version
[s
->i
] = '\0';
2127 } else if (s
->i
< sizeof(s
->version
) - 1)
2128 s
->version
[s
->i
++] = c
;
2129 } else if (c
== '\012')
2133 ssh
->agentfwd_enabled
= FALSE
;
2134 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2136 s
->vstring
[s
->vslen
] = 0;
2137 s
->vstring
[strcspn(s
->vstring
, "\r\n")] = '\0';/* remove EOL chars */
2140 vlog
= snewn(20 + s
->vslen
, char);
2141 sprintf(vlog
, "Server version: %s", s
->vstring
);
2145 ssh_detect_bugs(ssh
, s
->vstring
);
2148 * Decide which SSH protocol version to support.
2151 /* Anything strictly below "2.0" means protocol 1 is supported. */
2152 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2153 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2154 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2156 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2157 bombout(("SSH protocol version 1 required by user but not provided by server"));
2160 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2161 bombout(("SSH protocol version 2 required by user but not provided by server"));
2165 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2169 char verstring
[80], vlog
[100];
2170 sprintf(verstring
, "SSH-2.0-%s", sshver
);
2171 SHA_Init(&ssh
->exhashbase
);
2173 * Hash our version string and their version string.
2175 sha_string(&ssh
->exhashbase
, verstring
, strlen(verstring
));
2176 sha_string(&ssh
->exhashbase
, s
->vstring
, strcspn(s
->vstring
, "\r\n"));
2177 sprintf(vlog
, "We claim version: %s", verstring
);
2179 strcat(verstring
, "\012");
2180 logevent("Using SSH protocol version 2");
2181 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2182 ssh
->protocol
= ssh2_protocol
;
2184 ssh
->s_rdpkt
= ssh2_rdpkt
;
2189 char verstring
[80], vlog
[100];
2190 sprintf(verstring
, "SSH-%s-%s",
2191 (ssh_versioncmp(s
->version
, "1.5") <= 0 ? s
->version
: "1.5"),
2193 sprintf(vlog
, "We claim version: %s", verstring
);
2195 strcat(verstring
, "\012");
2197 logevent("Using SSH protocol version 1");
2198 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2199 ssh
->protocol
= ssh1_protocol
;
2201 ssh
->s_rdpkt
= ssh1_rdpkt
;
2203 update_specials_menu(ssh
->frontend
);
2204 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2211 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2213 crBegin(ssh
->ssh_gotdata_crstate
);
2216 * To begin with, feed the characters one by one to the
2217 * protocol initialisation / selection function do_ssh_init().
2218 * When that returns 0, we're done with the initial greeting
2219 * exchange and can move on to packet discipline.
2222 int ret
; /* need not be kept across crReturn */
2224 crReturnV
; /* more data please */
2225 ret
= do_ssh_init(ssh
, *data
);
2233 * We emerge from that loop when the initial negotiation is
2234 * over and we have selected an s_rdpkt function. Now pass
2235 * everything to s_rdpkt, and then pass the resulting packets
2236 * to the proper protocol handler.
2241 while (datalen
> 0) {
2242 struct Packet
*pktin
= ssh
->s_rdpkt(ssh
, &data
, &datalen
);
2244 ssh
->protocol(ssh
, NULL
, 0, pktin
);
2245 ssh_free_packet(pktin
);
2247 if (ssh
->state
== SSH_STATE_CLOSED
)
2255 static void ssh_do_close(Ssh ssh
)
2258 struct ssh_channel
*c
;
2260 ssh
->state
= SSH_STATE_CLOSED
;
2266 * Now we must shut down any port and X forwardings going
2267 * through this connection.
2269 if (ssh
->channels
) {
2270 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2273 x11_close(c
->u
.x11
.s
);
2276 pfd_close(c
->u
.pfd
.s
);
2279 del234(ssh
->channels
, c
);
2280 if (ssh
->version
== 2)
2281 bufchain_clear(&c
->v
.v2
.outbuffer
);
2287 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2290 Ssh ssh
= (Ssh
) plug
;
2293 /* A socket error has occurred. */
2294 logevent(error_msg
);
2295 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2297 /* Otherwise, the remote side closed the connection normally. */
2302 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2304 Ssh ssh
= (Ssh
) plug
;
2305 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2306 if (ssh
->state
== SSH_STATE_CLOSED
) {
2313 static void ssh_sent(Plug plug
, int bufsize
)
2315 Ssh ssh
= (Ssh
) plug
;
2317 * If the send backlog on the SSH socket itself clears, we
2318 * should unthrottle the whole world if it was throttled.
2320 if (bufsize
< SSH_MAX_BACKLOG
)
2321 ssh_throttle_all(ssh
, 0, bufsize
);
2325 * Connect to specified host and port.
2326 * Returns an error message, or NULL on success.
2327 * Also places the canonical host name into `realhost'. It must be
2328 * freed by the caller.
2330 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2331 char **realhost
, int nodelay
, int keepalive
)
2333 static const struct plug_function_table fn_table
= {
2343 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2344 if (!ssh
->savedhost
)
2345 fatalbox("Out of memory");
2346 strcpy(ssh
->savedhost
, host
);
2349 port
= 22; /* default ssh port */
2350 ssh
->savedport
= port
;
2355 logeventf(ssh
, "Looking up host \"%s\"", host
);
2356 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
);
2357 if ((err
= sk_addr_error(addr
)) != NULL
) {
2367 sk_getaddr(addr
, addrbuf
, 100);
2368 logeventf(ssh
, "Connecting to %s port %d", addrbuf
, port
);
2370 ssh
->fn
= &fn_table
;
2371 ssh
->s
= new_connection(addr
, *realhost
, port
,
2372 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2373 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2382 * Throttle or unthrottle the SSH connection.
2384 static void ssh1_throttle(Ssh ssh
, int adjust
)
2386 int old_count
= ssh
->v1_throttle_count
;
2387 ssh
->v1_throttle_count
+= adjust
;
2388 assert(ssh
->v1_throttle_count
>= 0);
2389 if (ssh
->v1_throttle_count
&& !old_count
) {
2390 sk_set_frozen(ssh
->s
, 1);
2391 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2392 sk_set_frozen(ssh
->s
, 0);
2397 * Throttle or unthrottle _all_ local data streams (for when sends
2398 * on the SSH connection itself back up).
2400 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2403 struct ssh_channel
*c
;
2405 if (enable
== ssh
->throttled_all
)
2407 ssh
->throttled_all
= enable
;
2408 ssh
->overall_bufsize
= bufsize
;
2411 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2413 case CHAN_MAINSESSION
:
2415 * This is treated separately, outside the switch.
2419 x11_override_throttle(c
->u
.x11
.s
, enable
);
2422 /* Agent channels require no buffer management. */
2425 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2432 * Username and password input, abstracted off into routines
2433 * reusable in several places - even between SSH1 and SSH2.
2436 /* Set up a username or password input loop on a given buffer. */
2437 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2439 ssh
->userpass_input_buffer
= buffer
;
2440 ssh
->userpass_input_buflen
= buflen
;
2441 ssh
->userpass_input_bufpos
= 0;
2442 ssh
->userpass_input_echo
= echo
;
2446 * Process some terminal data in the course of username/password
2447 * input. Returns >0 for success (line of input returned in
2448 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2449 * for inconclusive (keep waiting for more input please).
2451 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2456 switch (c
= *in
++) {
2459 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2460 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2465 if (ssh
->userpass_input_bufpos
> 0) {
2466 if (ssh
->userpass_input_echo
)
2467 c_write_str(ssh
, "\b \b");
2468 ssh
->userpass_input_bufpos
--;
2473 while (ssh
->userpass_input_bufpos
> 0) {
2474 if (ssh
->userpass_input_echo
)
2475 c_write_str(ssh
, "\b \b");
2476 ssh
->userpass_input_bufpos
--;
2485 * This simplistic check for printability is disabled
2486 * when we're doing password input, because some people
2487 * have control characters in their passwords.o
2489 if ((!ssh
->userpass_input_echo
||
2490 (c
>= ' ' && c
<= '~') ||
2491 ((unsigned char) c
>= 160))
2492 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2493 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2494 if (ssh
->userpass_input_echo
)
2495 c_write(ssh
, &c
, 1);
2503 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2505 Ssh ssh
= (Ssh
) sshv
;
2507 ssh
->agent_response
= reply
;
2508 ssh
->agent_response_len
= replylen
;
2510 if (ssh
->version
== 1)
2511 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2513 do_ssh2_authconn(ssh
, NULL
, -1, NULL
);
2516 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2518 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2520 void *sentreply
= reply
;
2523 /* Fake SSH_AGENT_FAILURE. */
2524 sentreply
= "\0\0\0\1\5";
2527 if (ssh
->version
== 2) {
2528 ssh2_add_channel_data(c
, sentreply
, replylen
);
2531 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2532 PKT_INT
, c
->remoteid
,
2535 PKT_DATA
, sentreply
, replylen
,
2544 * Handle the key exchange and user authentication phases.
2546 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
2547 struct Packet
*pktin
)
2550 unsigned char cookie
[8], *ptr
;
2551 struct RSAKey servkey
, hostkey
;
2552 struct MD5Context md5c
;
2553 struct do_ssh1_login_state
{
2555 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2556 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2557 int tried_publickey
, tried_agent
;
2558 int tis_auth_refused
, ccard_auth_refused
;
2559 unsigned char session_id
[16];
2562 void *publickey_blob
;
2563 int publickey_bloblen
;
2569 unsigned char request
[5], *response
, *p
;
2578 crState(do_ssh1_login_state
);
2580 crBegin(ssh
->do_ssh1_login_crstate
);
2585 if (pktin
->type
!= SSH1_SMSG_PUBLIC_KEY
) {
2586 bombout(("Public key packet not received"));
2590 logevent("Received public keys");
2592 ptr
= ssh_pkt_getdata(pktin
, 8);
2594 bombout(("SSH1 public key packet stopped before random cookie"));
2597 memcpy(cookie
, ptr
, 8);
2599 if (!ssh1_pkt_getrsakey(pktin
, &servkey
, &s
->keystr1
) ||
2600 !ssh1_pkt_getrsakey(pktin
, &hostkey
, &s
->keystr2
)) {
2601 bombout(("Failed to read SSH1 public keys from public key packet"));
2606 * Log the host key fingerprint.
2610 logevent("Host key fingerprint is:");
2611 strcpy(logmsg
, " ");
2612 hostkey
.comment
= NULL
;
2613 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2614 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2618 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(pktin
);
2619 s
->supported_ciphers_mask
= ssh_pkt_getuint32(pktin
);
2620 s
->supported_auths_mask
= ssh_pkt_getuint32(pktin
);
2622 ssh
->v1_local_protoflags
=
2623 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2624 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2627 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2628 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2629 MD5Update(&md5c
, cookie
, 8);
2630 MD5Final(s
->session_id
, &md5c
);
2632 for (i
= 0; i
< 32; i
++)
2633 ssh
->session_key
[i
] = random_byte();
2636 * Verify that the `bits' and `bytes' parameters match.
2638 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
2639 servkey
.bits
> servkey
.bytes
* 8) {
2640 bombout(("SSH1 public keys were badly formatted"));
2644 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2646 s
->rsabuf
= snewn(s
->len
, unsigned char);
2648 fatalbox("Out of memory");
2651 * Verify the host key.
2655 * First format the key into a string.
2657 int len
= rsastr_len(&hostkey
);
2658 char fingerprint
[100];
2659 char *keystr
= snewn(len
, char);
2661 fatalbox("Out of memory");
2662 rsastr_fmt(keystr
, &hostkey
);
2663 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2664 verify_ssh_host_key(ssh
->frontend
,
2665 ssh
->savedhost
, ssh
->savedport
, "rsa", keystr
,
2670 for (i
= 0; i
< 32; i
++) {
2671 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2673 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2676 if (hostkey
.bytes
> servkey
.bytes
) {
2677 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
2679 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2681 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2683 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2686 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2690 logevent("Encrypted session key");
2693 int cipher_chosen
= 0, warn
= 0;
2694 char *cipher_string
= NULL
;
2696 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2697 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
2698 if (next_cipher
== CIPHER_WARN
) {
2699 /* If/when we choose a cipher, warn about it */
2701 } else if (next_cipher
== CIPHER_AES
) {
2702 /* XXX Probably don't need to mention this. */
2703 logevent("AES not supported in SSH1, skipping");
2705 switch (next_cipher
) {
2706 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2707 cipher_string
= "3DES"; break;
2708 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2709 cipher_string
= "Blowfish"; break;
2710 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2711 cipher_string
= "single-DES"; break;
2713 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2717 if (!cipher_chosen
) {
2718 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2719 bombout(("Server violates SSH 1 protocol by not "
2720 "supporting 3DES encryption"));
2722 /* shouldn't happen */
2723 bombout(("No supported ciphers found"));
2727 /* Warn about chosen cipher if necessary. */
2729 askcipher(ssh
->frontend
, cipher_string
, 0);
2732 switch (s
->cipher_type
) {
2733 case SSH_CIPHER_3DES
:
2734 logevent("Using 3DES encryption");
2736 case SSH_CIPHER_DES
:
2737 logevent("Using single-DES encryption");
2739 case SSH_CIPHER_BLOWFISH
:
2740 logevent("Using Blowfish encryption");
2744 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
2745 PKT_CHAR
, s
->cipher_type
,
2746 PKT_DATA
, cookie
, 8,
2747 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
2748 PKT_DATA
, s
->rsabuf
, s
->len
,
2749 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
2751 logevent("Trying to enable encryption...");
2755 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2756 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
2758 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
2759 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
2760 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
2762 ssh
->crcda_ctx
= crcda_make_context();
2763 logevent("Installing CRC compensation attack detector");
2765 if (servkey
.modulus
) {
2766 sfree(servkey
.modulus
);
2767 servkey
.modulus
= NULL
;
2769 if (servkey
.exponent
) {
2770 sfree(servkey
.exponent
);
2771 servkey
.exponent
= NULL
;
2773 if (hostkey
.modulus
) {
2774 sfree(hostkey
.modulus
);
2775 hostkey
.modulus
= NULL
;
2777 if (hostkey
.exponent
) {
2778 sfree(hostkey
.exponent
);
2779 hostkey
.exponent
= NULL
;
2783 if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
2784 bombout(("Encryption not successfully enabled"));
2788 logevent("Successfully started encryption");
2792 if (!*ssh
->cfg
.username
) {
2793 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2794 if (!ssh_get_line("login as: ",
2795 s
->username
, sizeof(s
->username
), FALSE
)) {
2797 * get_line failed to get a username.
2800 logevent("No username provided. Abandoning session.");
2801 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2805 int ret
; /* need not be kept over crReturn */
2806 c_write_str(ssh
, "login as: ");
2809 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
2811 crWaitUntil(!pktin
);
2812 ret
= process_userpass_input(ssh
, in
, inlen
);
2816 c_write_str(ssh
, "\r\n");
2819 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
2820 s
->username
[sizeof(s
->username
)-1] = '\0';
2823 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
2825 char userlog
[22 + sizeof(s
->username
)];
2826 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
2828 if (flags
& FLAG_INTERACTIVE
&&
2829 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2830 strcat(userlog
, "\r\n");
2831 c_write_str(ssh
, userlog
);
2838 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2839 /* We must not attempt PK auth. Pretend we've already tried it. */
2840 s
->tried_publickey
= s
->tried_agent
= 1;
2842 s
->tried_publickey
= s
->tried_agent
= 0;
2844 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
2845 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
2846 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
2847 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
2848 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
2849 s
->publickey_blob
= NULL
;
2851 s
->publickey_blob
= NULL
;
2853 while (pktin
->type
== SSH1_SMSG_FAILURE
) {
2854 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2856 if (agent_exists() && !s
->tried_agent
) {
2858 * Attempt RSA authentication using Pageant.
2864 logevent("Pageant is running. Requesting keys.");
2866 /* Request the keys held by the agent. */
2867 PUT_32BIT(s
->request
, 1);
2868 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2869 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
2870 ssh_agent_callback
, ssh
)) {
2874 bombout(("Unexpected data from server while waiting"
2875 " for agent response"));
2878 } while (pktin
|| inlen
> 0);
2879 r
= ssh
->agent_response
;
2880 s
->responselen
= ssh
->agent_response_len
;
2882 s
->response
= (unsigned char *) r
;
2883 if (s
->response
&& s
->responselen
>= 5 &&
2884 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
2885 s
->p
= s
->response
+ 5;
2886 s
->nkeys
= GET_32BIT(s
->p
);
2890 sprintf(buf
, "Pageant has %d SSH1 keys", s
->nkeys
);
2893 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
2896 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
2899 if (s
->publickey_blob
&&
2900 !memcmp(s
->p
, s
->publickey_blob
,
2901 s
->publickey_bloblen
)) {
2902 logevent("This key matches configured key file");
2903 s
->tried_publickey
= 1;
2908 do { /* do while (0) to make breaking easy */
2909 n
= ssh1_read_bignum
2910 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
2915 n
= ssh1_read_bignum
2916 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
2921 if (s
->responselen
- (s
->p
-s
->response
) < 4)
2923 s
->commentlen
= GET_32BIT(s
->p
);
2925 if (s
->responselen
- (s
->p
-s
->response
) <
2928 s
->commentp
= (char *)s
->p
;
2929 s
->p
+= s
->commentlen
;
2933 logevent("Pageant key list packet was truncated");
2937 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
2938 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
2940 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2941 logevent("Key refused");
2944 logevent("Received RSA challenge");
2945 if ((s
->challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
2946 bombout(("Server's RSA challenge was badly formatted"));
2951 char *agentreq
, *q
, *ret
;
2954 len
= 1 + 4; /* message type, bit count */
2955 len
+= ssh1_bignum_length(s
->key
.exponent
);
2956 len
+= ssh1_bignum_length(s
->key
.modulus
);
2957 len
+= ssh1_bignum_length(s
->challenge
);
2958 len
+= 16; /* session id */
2959 len
+= 4; /* response format */
2960 agentreq
= snewn(4 + len
, char);
2961 PUT_32BIT(agentreq
, len
);
2963 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
2964 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
2966 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
2967 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
2968 q
+= ssh1_write_bignum(q
, s
->challenge
);
2969 memcpy(q
, s
->session_id
, 16);
2971 PUT_32BIT(q
, 1); /* response format */
2972 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
2973 ssh_agent_callback
, ssh
)) {
2978 bombout(("Unexpected data from server"
2979 " while waiting for agent"
2983 } while (pktin
|| inlen
> 0);
2984 vret
= ssh
->agent_response
;
2985 retlen
= ssh
->agent_response_len
;
2990 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
2991 logevent("Sending Pageant's response");
2992 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
2993 PKT_DATA
, ret
+ 5, 16,
2997 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
2999 ("Pageant's response accepted");
3000 if (flags
& FLAG_VERBOSE
) {
3001 c_write_str(ssh
, "Authenticated using"
3003 c_write(ssh
, s
->commentp
,
3005 c_write_str(ssh
, "\" from agent\r\n");
3010 ("Pageant's response not accepted");
3013 ("Pageant failed to answer challenge");
3017 logevent("No reply received from Pageant");
3020 freebn(s
->key
.exponent
);
3021 freebn(s
->key
.modulus
);
3022 freebn(s
->challenge
);
3031 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
3032 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
3034 if (ssh
->cfg
.try_tis_auth
&&
3035 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3036 !s
->tis_auth_refused
) {
3037 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3038 logevent("Requested TIS authentication");
3039 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3041 if (pktin
->type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3042 logevent("TIS authentication declined");
3043 if (flags
& FLAG_INTERACTIVE
)
3044 c_write_str(ssh
, "TIS authentication refused.\r\n");
3045 s
->tis_auth_refused
= 1;
3051 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3053 bombout(("TIS challenge packet was badly formed"));
3056 logevent("Received TIS challenge");
3057 if (challengelen
> sizeof(s
->prompt
) - 1)
3058 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3059 memcpy(s
->prompt
, challenge
, challengelen
);
3060 /* Prompt heuristic comes from OpenSSH */
3061 strncpy(s
->prompt
+ challengelen
,
3062 memchr(s
->prompt
, '\n', challengelen
) ?
3063 "": "\r\nResponse: ",
3064 (sizeof s
->prompt
) - challengelen
);
3065 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
3068 if (ssh
->cfg
.try_tis_auth
&&
3069 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3070 !s
->ccard_auth_refused
) {
3071 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3072 logevent("Requested CryptoCard authentication");
3073 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3075 if (pktin
->type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3076 logevent("CryptoCard authentication declined");
3077 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3078 s
->ccard_auth_refused
= 1;
3084 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3086 bombout(("CryptoCard challenge packet was badly formed"));
3089 logevent("Received CryptoCard challenge");
3090 if (challengelen
> sizeof(s
->prompt
) - 1)
3091 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3092 memcpy(s
->prompt
, challenge
, challengelen
);
3093 strncpy(s
->prompt
+ challengelen
,
3094 memchr(s
->prompt
, '\n', challengelen
) ?
3095 "" : "\r\nResponse: ",
3096 sizeof(s
->prompt
) - challengelen
);
3097 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
3100 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3101 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
3102 s
->username
, ssh
->savedhost
);
3104 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3105 char *comment
= NULL
;
3108 if (flags
& FLAG_VERBOSE
)
3109 c_write_str(ssh
, "Trying public key authentication.\r\n");
3110 logeventf(ssh
, "Trying public key \"%s\"",
3111 filename_to_str(&ssh
->cfg
.keyfile
));
3112 type
= key_type(&ssh
->cfg
.keyfile
);
3113 if (type
!= SSH_KEYTYPE_SSH1
) {
3114 sprintf(msgbuf
, "Key is of wrong type (%s)",
3115 key_type_to_str(type
));
3117 c_write_str(ssh
, msgbuf
);
3118 c_write_str(ssh
, "\r\n");
3119 s
->tried_publickey
= 1;
3122 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
3123 if (flags
& FLAG_VERBOSE
)
3124 c_write_str(ssh
, "No passphrase required.\r\n");
3127 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
3132 * Show password prompt, having first obtained it via a TIS
3133 * or CryptoCard exchange if we're doing TIS or CryptoCard
3137 if (!ssh_get_line(s
->prompt
, s
->password
,
3138 sizeof(s
->password
), TRUE
)) {
3140 * get_line failed to get a password (for example
3141 * because one was supplied on the command line
3142 * which has already failed to work). Terminate.
3144 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
3145 PKT_STR
, "No more passwords available to try",
3147 logevent("Unable to authenticate");
3148 connection_fatal(ssh
->frontend
, "Unable to authenticate");
3149 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3153 /* Prompt may have come from server. We've munged it a bit, so
3154 * we know it to be zero-terminated at least once. */
3155 int ret
; /* need not be saved over crReturn */
3156 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3159 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3161 crWaitUntil(!pktin
);
3162 ret
= process_userpass_input(ssh
, in
, inlen
);
3166 c_write_str(ssh
, "\r\n");
3170 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3172 * Try public key authentication with the specified
3175 s
->tried_publickey
= 1;
3178 const char *error
= NULL
;
3179 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3182 c_write_str(ssh
, "Couldn't load private key from ");
3183 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3184 c_write_str(ssh
, " (");
3185 c_write_str(ssh
, error
);
3186 c_write_str(ssh
, ").\r\n");
3187 continue; /* go and try password */
3190 c_write_str(ssh
, "Wrong passphrase.\r\n");
3191 s
->tried_publickey
= 0;
3192 continue; /* try again */
3197 * Send a public key attempt.
3199 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3200 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3203 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3204 c_write_str(ssh
, "Server refused our public key.\r\n");
3205 continue; /* go and try password */
3207 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3208 bombout(("Bizarre response to offer of public key"));
3214 unsigned char buffer
[32];
3215 Bignum challenge
, response
;
3217 if ((challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3218 bombout(("Server's RSA challenge was badly formatted"));
3221 response
= rsadecrypt(challenge
, &s
->key
);
3222 freebn(s
->key
.private_exponent
);/* burn the evidence */
3224 for (i
= 0; i
< 32; i
++) {
3225 buffer
[i
] = bignum_byte(response
, 31 - i
);
3229 MD5Update(&md5c
, buffer
, 32);
3230 MD5Update(&md5c
, s
->session_id
, 16);
3231 MD5Final(buffer
, &md5c
);
3233 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3234 PKT_DATA
, buffer
, 16, PKT_END
);
3241 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3242 if (flags
& FLAG_VERBOSE
)
3243 c_write_str(ssh
, "Failed to authenticate with"
3244 " our public key.\r\n");
3245 continue; /* go and try password */
3246 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3247 bombout(("Bizarre response to RSA authentication response"));
3251 break; /* we're through! */
3253 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3255 * Defence against traffic analysis: we send a
3256 * whole bunch of packets containing strings of
3257 * different lengths. One of these strings is the
3258 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3259 * The others are all random data in
3260 * SSH1_MSG_IGNORE packets. This way a passive
3261 * listener can't tell which is the password, and
3262 * hence can't deduce the password length.
3264 * Anybody with a password length greater than 16
3265 * bytes is going to have enough entropy in their
3266 * password that a listener won't find it _that_
3267 * much help to know how long it is. So what we'll
3270 * - if password length < 16, we send 15 packets
3271 * containing string lengths 1 through 15
3273 * - otherwise, we let N be the nearest multiple
3274 * of 8 below the password length, and send 8
3275 * packets containing string lengths N through
3276 * N+7. This won't obscure the order of
3277 * magnitude of the password length, but it will
3278 * introduce a bit of extra uncertainty.
3280 * A few servers (the old 1.2.18 through 1.2.22)
3281 * can't deal with SSH1_MSG_IGNORE. For these
3282 * servers, we need an alternative defence. We make
3283 * use of the fact that the password is interpreted
3284 * as a C string: so we can append a NUL, then some
3287 * One server (a Cisco one) can deal with neither
3288 * SSH1_MSG_IGNORE _nor_ a padded password string.
3289 * For this server we are left with no defences
3290 * against password length sniffing.
3292 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3294 * The server can deal with SSH1_MSG_IGNORE, so
3295 * we can use the primary defence.
3297 int bottom
, top
, pwlen
, i
;
3300 pwlen
= strlen(s
->password
);
3302 bottom
= 0; /* zero length passwords are OK! :-) */
3305 bottom
= pwlen
& ~7;
3309 assert(pwlen
>= bottom
&& pwlen
<= top
);
3311 randomstr
= snewn(top
+ 1, char);
3313 for (i
= bottom
; i
<= top
; i
++) {
3315 defer_packet(ssh
, s
->pwpkt_type
,
3316 PKTT_PASSWORD
, PKT_STR
, s
->password
,
3317 PKTT_OTHER
, PKT_END
);
3319 for (j
= 0; j
< i
; j
++) {
3321 randomstr
[j
] = random_byte();
3322 } while (randomstr
[j
] == '\0');
3324 randomstr
[i
] = '\0';
3325 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3326 PKT_STR
, randomstr
, PKT_END
);
3329 logevent("Sending password with camouflage packets");
3330 ssh_pkt_defersend(ssh
);
3333 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3335 * The server can't deal with SSH1_MSG_IGNORE
3336 * but can deal with padded passwords, so we
3337 * can use the secondary defence.
3343 len
= strlen(s
->password
);
3344 if (len
< sizeof(string
)) {
3346 strcpy(string
, s
->password
);
3347 len
++; /* cover the zero byte */
3348 while (len
< sizeof(string
)) {
3349 string
[len
++] = (char) random_byte();
3354 logevent("Sending length-padded password");
3355 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3356 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3357 PKTT_OTHER
, PKT_END
);
3360 * The server has _both_
3361 * BUG_CHOKES_ON_SSH1_IGNORE and
3362 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3363 * therefore nothing we can do.
3366 len
= strlen(s
->password
);
3367 logevent("Sending unpadded password");
3368 send_packet(ssh
, s
->pwpkt_type
,
3369 PKTT_PASSWORD
, PKT_INT
, len
,
3370 PKT_DATA
, s
->password
, len
,
3371 PKTT_OTHER
, PKT_END
);
3374 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3375 PKT_STR
, s
->password
, PKTT_OTHER
, PKT_END
);
3378 logevent("Sent password");
3379 memset(s
->password
, 0, strlen(s
->password
));
3381 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3382 if (flags
& FLAG_VERBOSE
)
3383 c_write_str(ssh
, "Access denied\r\n");
3384 logevent("Authentication refused");
3385 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3386 bombout(("Strange packet received, type %d", pktin
->type
));
3391 logevent("Authentication successful");
3396 void sshfwd_close(struct ssh_channel
*c
)
3400 if (ssh
->state
!= SSH_STATE_SESSION
) {
3401 assert(ssh
->state
== SSH_STATE_CLOSED
);
3405 if (c
&& !c
->closes
) {
3407 * If the channel's remoteid is -1, we have sent
3408 * CHANNEL_OPEN for this channel, but it hasn't even been
3409 * acknowledged by the server. So we must set a close flag
3410 * on it now, and then when the server acks the channel
3411 * open, we can close it then.
3413 if (((int)c
->remoteid
) != -1) {
3414 if (ssh
->version
== 1) {
3415 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3418 struct Packet
*pktout
;
3419 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3420 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
3421 ssh2_pkt_send(ssh
, pktout
);
3424 c
->closes
= 1; /* sent MSG_CLOSE */
3425 if (c
->type
== CHAN_X11
) {
3427 logevent("Forwarded X11 connection terminated");
3428 } else if (c
->type
== CHAN_SOCKDATA
||
3429 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3431 logevent("Forwarded port closed");
3436 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3440 if (ssh
->state
!= SSH_STATE_SESSION
) {
3441 assert(ssh
->state
== SSH_STATE_CLOSED
);
3445 if (ssh
->version
== 1) {
3446 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3447 PKT_INT
, c
->remoteid
,
3449 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3450 PKTT_OTHER
, PKT_END
);
3452 * In SSH1 we can return 0 here - implying that forwarded
3453 * connections are never individually throttled - because
3454 * the only circumstance that can cause throttling will be
3455 * the whole SSH connection backing up, in which case
3456 * _everything_ will be throttled as a whole.
3460 ssh2_add_channel_data(c
, buf
, len
);
3461 return ssh2_try_send(c
);
3465 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3469 if (ssh
->state
!= SSH_STATE_SESSION
) {
3470 assert(ssh
->state
== SSH_STATE_CLOSED
);
3474 if (ssh
->version
== 1) {
3475 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3476 c
->v
.v1
.throttling
= 0;
3477 ssh1_throttle(ssh
, -1);
3480 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3484 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
3485 struct Packet
*pktin
)
3487 crBegin(ssh
->ssh1_protocol_crstate
);
3491 while (!do_ssh1_login(ssh
, in
, inlen
, pktin
)) {
3494 if (ssh
->state
== SSH_STATE_CLOSED
)
3497 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
3498 logevent("Requesting agent forwarding");
3499 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
3503 if (pktin
->type
!= SSH1_SMSG_SUCCESS
3504 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
3505 bombout(("Protocol confusion"));
3507 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3508 logevent("Agent forwarding refused");
3510 logevent("Agent forwarding enabled");
3511 ssh
->agentfwd_enabled
= TRUE
;
3515 if (ssh
->cfg
.x11_forward
) {
3516 char proto
[20], data
[64];
3517 logevent("Requesting X11 forwarding");
3518 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
3519 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
3520 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
3521 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
3522 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
3523 PKT_STR
, proto
, PKT_STR
, data
,
3524 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
3527 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
3528 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
3533 if (pktin
->type
!= SSH1_SMSG_SUCCESS
3534 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
3535 bombout(("Protocol confusion"));
3537 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3538 logevent("X11 forwarding refused");
3540 logevent("X11 forwarding enabled");
3541 ssh
->X11_fwd_enabled
= TRUE
;
3548 int sport
,dport
,sserv
,dserv
;
3549 char sports
[256], dports
[256], saddr
[256], host
[256];
3551 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3552 /* Add port forwardings. */
3553 ssh
->portfwd_strptr
= ssh
->cfg
.portfwd
;
3554 while (*ssh
->portfwd_strptr
) {
3555 type
= *ssh
->portfwd_strptr
++;
3558 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= '\t') {
3559 if (*ssh
->portfwd_strptr
== ':') {
3561 * We've seen a colon in the middle of the
3562 * source port number. This means that
3563 * everything we've seen until now is the
3564 * source _address_, so we'll move it into
3565 * saddr and start sports from the beginning
3568 ssh
->portfwd_strptr
++;
3570 strcpy(saddr
, sports
);
3573 if (n
< 255) sports
[n
++] = *ssh
->portfwd_strptr
++;
3577 if (*ssh
->portfwd_strptr
== '\t')
3578 ssh
->portfwd_strptr
++;
3580 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= ':') {
3581 if (n
< 255) host
[n
++] = *ssh
->portfwd_strptr
++;
3584 if (*ssh
->portfwd_strptr
== ':')
3585 ssh
->portfwd_strptr
++;
3587 while (*ssh
->portfwd_strptr
) {
3588 if (n
< 255) dports
[n
++] = *ssh
->portfwd_strptr
++;
3591 ssh
->portfwd_strptr
++;
3592 dport
= atoi(dports
);
3596 dport
= net_service_lookup(dports
);
3598 logeventf(ssh
, "Service lookup failed for"
3599 " destination port \"%s\"", dports
);
3603 while (*ssh
->portfwd_strptr
) ssh
->portfwd_strptr
++;
3605 ssh
->portfwd_strptr
++; /* eat the NUL and move to next one */
3607 sport
= atoi(sports
);
3611 sport
= net_service_lookup(sports
);
3613 logeventf(ssh
, "Service lookup failed for source"
3614 " port \"%s\"", sports
);
3617 if (sport
&& dport
) {
3618 /* Set up a description of the source port. */
3619 static char *sportdesc
;
3620 sportdesc
= dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
3621 (int)(*saddr?
strlen(saddr
):0), *saddr?saddr
:NULL
,
3622 (int)(*saddr?
1:0), ":",
3623 (int)(sserv ?
strlen(sports
) : 0), sports
,
3624 sserv
, "(", sport
, sserv
, ")");
3626 /* Verbose description of the destination port */
3627 char *dportdesc
= dupprintf("%s:%.*s%.*s%d%.*s",
3629 (int)(dserv ?
strlen(dports
) : 0), dports
,
3630 dserv
, "(", dport
, dserv
, ")");
3631 const char *err
= pfd_addforward(host
, dport
,
3632 *saddr ? saddr
: NULL
,
3633 sport
, ssh
, &ssh
->cfg
);
3635 logeventf(ssh
, "Local port %s forward to %s"
3636 " failed: %s", sportdesc
, dportdesc
, err
);
3638 logeventf(ssh
, "Local port %s forwarding to %s",
3639 sportdesc
, dportdesc
);
3642 } else if (type
== 'D') {
3643 const char *err
= pfd_addforward(NULL
, -1,
3644 *saddr ? saddr
: NULL
,
3645 sport
, ssh
, &ssh
->cfg
);
3647 logeventf(ssh
, "Local port %s SOCKS dynamic forward"
3648 " setup failed: %s", sportdesc
, err
);
3650 logeventf(ssh
, "Local port %s doing SOCKS"
3651 " dynamic forwarding", sportdesc
);
3654 struct ssh_rportfwd
*pf
;
3655 pf
= snew(struct ssh_rportfwd
);
3656 strcpy(pf
->dhost
, host
);
3660 "SSH1 cannot handle source address spec \"%s:%d\"; ignoring",
3663 if (add234(ssh
->rportfwds
, pf
) != pf
) {
3665 "Duplicate remote port forwarding to %s:%d",
3669 logeventf(ssh
, "Requesting remote port %.*s%.*s%d%.*s"
3670 " forward to %s:%.*s%.*s%d%.*s",
3671 (int)(sserv ?
strlen(sports
) : 0), sports
,
3672 sserv
, "(", sport
, sserv
, ")",
3674 (int)(dserv ?
strlen(dports
) : 0), dports
,
3675 dserv
, "(", dport
, dserv
, ")");
3676 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
3684 if (pktin
->type
!= SSH1_SMSG_SUCCESS
3685 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
3686 bombout(("Protocol confusion"));
3688 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3689 c_write_str(ssh
, "Server refused port"
3692 logevent("Remote port forwarding enabled");
3700 if (!ssh
->cfg
.nopty
) {
3701 /* Unpick the terminal-speed string. */
3702 /* XXX perhaps we should allow no speeds to be sent. */
3703 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
3704 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
3705 /* Send the pty request. */
3706 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
3707 PKT_STR
, ssh
->cfg
.termtype
,
3708 PKT_INT
, ssh
->term_height
,
3709 PKT_INT
, ssh
->term_width
,
3710 PKT_INT
, 0, PKT_INT
, 0, /* width,height in pixels */
3711 PKT_CHAR
, 192, PKT_INT
, ssh
->ispeed
, /* TTY_OP_ISPEED */
3712 PKT_CHAR
, 193, PKT_INT
, ssh
->ospeed
, /* TTY_OP_OSPEED */
3713 PKT_CHAR
, 0, PKT_END
);
3714 ssh
->state
= SSH_STATE_INTERMED
;
3718 if (pktin
->type
!= SSH1_SMSG_SUCCESS
3719 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
3720 bombout(("Protocol confusion"));
3722 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3723 c_write_str(ssh
, "Server refused to allocate pty\r\n");
3724 ssh
->editing
= ssh
->echoing
= 1;
3726 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
3727 ssh
->ospeed
, ssh
->ispeed
);
3729 ssh
->editing
= ssh
->echoing
= 1;
3732 if (ssh
->cfg
.compression
) {
3733 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
3737 if (pktin
->type
!= SSH1_SMSG_SUCCESS
3738 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
3739 bombout(("Protocol confusion"));
3741 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3742 c_write_str(ssh
, "Server refused to compress\r\n");
3744 logevent("Started compression");
3745 ssh
->v1_compressing
= TRUE
;
3746 ssh
->cs_comp_ctx
= zlib_compress_init();
3747 logevent("Initialised zlib (RFC1950) compression");
3748 ssh
->sc_comp_ctx
= zlib_decompress_init();
3749 logevent("Initialised zlib (RFC1950) decompression");
3753 * Start the shell or command.
3755 * Special case: if the first-choice command is an SSH2
3756 * subsystem (hence not usable here) and the second choice
3757 * exists, we fall straight back to that.
3760 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
3762 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
3763 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
3764 ssh
->fallback_cmd
= TRUE
;
3767 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
3769 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
3770 logevent("Started session");
3773 ssh
->state
= SSH_STATE_SESSION
;
3774 if (ssh
->size_needed
)
3775 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
3776 if (ssh
->eof_needed
)
3777 ssh_special(ssh
, TS_EOF
);
3780 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
3782 ssh
->channels
= newtree234(ssh_channelcmp
);
3786 if (pktin
->type
== SSH1_SMSG_STDOUT_DATA
||
3787 pktin
->type
== SSH1_SMSG_STDERR_DATA
) {
3789 int stringlen
, bufsize
;
3791 ssh_pkt_getstring(pktin
, &string
, &stringlen
);
3792 if (string
== NULL
) {
3793 bombout(("Incoming terminal data packet was badly formed"));
3798 from_backend(ssh
->frontend
,
3799 pktin
->type
== SSH1_SMSG_STDERR_DATA
,
3801 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3802 ssh
->v1_stdout_throttling
= 1;
3803 ssh1_throttle(ssh
, +1);
3805 } else if (pktin
->type
== SSH1_MSG_DISCONNECT
) {
3806 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3807 logevent("Received disconnect request");
3809 } else if (pktin
->type
== SSH1_SMSG_X11_OPEN
) {
3810 /* Remote side is trying to open a channel to talk to our
3811 * X-Server. Give them back a local channel number. */
3812 struct ssh_channel
*c
;
3813 int remoteid
= ssh_pkt_getuint32(pktin
);
3815 logevent("Received X11 connect request");
3816 /* Refuse if X11 forwarding is disabled. */
3817 if (!ssh
->X11_fwd_enabled
) {
3818 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3819 PKT_INT
, remoteid
, PKT_END
);
3820 logevent("Rejected X11 connect request");
3822 c
= snew(struct ssh_channel
);
3825 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
3826 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
3827 logevent("Opening X11 forward connection failed");
3829 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3830 PKT_INT
, remoteid
, PKT_END
);
3833 ("Opening X11 forward connection succeeded");
3834 c
->remoteid
= remoteid
;
3835 c
->localid
= alloc_channel_id(ssh
);
3837 c
->v
.v1
.throttling
= 0;
3838 c
->type
= CHAN_X11
; /* identify channel type */
3839 add234(ssh
->channels
, c
);
3840 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3841 PKT_INT
, c
->remoteid
, PKT_INT
,
3842 c
->localid
, PKT_END
);
3843 logevent("Opened X11 forward channel");
3846 } else if (pktin
->type
== SSH1_SMSG_AGENT_OPEN
) {
3847 /* Remote side is trying to open a channel to talk to our
3848 * agent. Give them back a local channel number. */
3849 struct ssh_channel
*c
;
3850 int remoteid
= ssh_pkt_getuint32(pktin
);
3852 /* Refuse if agent forwarding is disabled. */
3853 if (!ssh
->agentfwd_enabled
) {
3854 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3855 PKT_INT
, remoteid
, PKT_END
);
3857 c
= snew(struct ssh_channel
);
3859 c
->remoteid
= remoteid
;
3860 c
->localid
= alloc_channel_id(ssh
);
3862 c
->v
.v1
.throttling
= 0;
3863 c
->type
= CHAN_AGENT
; /* identify channel type */
3864 c
->u
.a
.lensofar
= 0;
3865 add234(ssh
->channels
, c
);
3866 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3867 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
3870 } else if (pktin
->type
== SSH1_MSG_PORT_OPEN
) {
3871 /* Remote side is trying to open a channel to talk to a
3872 * forwarded port. Give them back a local channel number. */
3873 struct ssh_channel
*c
;
3874 struct ssh_rportfwd pf
;
3877 char *host
, buf
[1024];
3879 c
= snew(struct ssh_channel
);
3882 remoteid
= ssh_pkt_getuint32(pktin
);
3883 ssh_pkt_getstring(pktin
, &host
, &hostsize
);
3884 port
= ssh_pkt_getuint32(pktin
);
3886 if (hostsize
>= lenof(pf
.dhost
))
3887 hostsize
= lenof(pf
.dhost
)-1;
3888 memcpy(pf
.dhost
, host
, hostsize
);
3889 pf
.dhost
[hostsize
] = '\0';
3892 if (find234(ssh
->rportfwds
, &pf
, NULL
) == NULL
) {
3893 sprintf(buf
, "Rejected remote port open request for %s:%d",
3896 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3897 PKT_INT
, remoteid
, PKT_END
);
3899 sprintf(buf
, "Received remote port open request for %s:%d",
3902 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
3906 sprintf(buf
, "Port open failed: %s", e
);
3909 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3910 PKT_INT
, remoteid
, PKT_END
);
3912 c
->remoteid
= remoteid
;
3913 c
->localid
= alloc_channel_id(ssh
);
3915 c
->v
.v1
.throttling
= 0;
3916 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
3917 add234(ssh
->channels
, c
);
3918 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3919 PKT_INT
, c
->remoteid
, PKT_INT
,
3920 c
->localid
, PKT_END
);
3921 logevent("Forwarded port opened successfully");
3925 } else if (pktin
->type
== SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
) {
3926 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
3927 unsigned int localid
= ssh_pkt_getuint32(pktin
);
3928 struct ssh_channel
*c
;
3930 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
3931 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3932 c
->remoteid
= localid
;
3933 c
->type
= CHAN_SOCKDATA
;
3934 c
->v
.v1
.throttling
= 0;
3935 pfd_confirm(c
->u
.pfd
.s
);
3938 if (c
&& c
->closes
) {
3940 * We have a pending close on this channel,
3941 * which we decided on before the server acked
3942 * the channel open. So now we know the
3943 * remoteid, we can close it again.
3945 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
3946 PKT_INT
, c
->remoteid
, PKT_END
);
3949 } else if (pktin
->type
== SSH1_MSG_CHANNEL_OPEN_FAILURE
) {
3950 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
3951 struct ssh_channel
*c
;
3953 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
3954 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3955 logevent("Forwarded connection refused by server");
3956 pfd_close(c
->u
.pfd
.s
);
3957 del234(ssh
->channels
, c
);
3961 } else if (pktin
->type
== SSH1_MSG_CHANNEL_CLOSE
||
3962 pktin
->type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
3963 /* Remote side closes a channel. */
3964 unsigned i
= ssh_pkt_getuint32(pktin
);
3965 struct ssh_channel
*c
;
3966 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
3967 if (c
&& ((int)c
->remoteid
) != -1) {
3970 (pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
3972 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
3973 logevent("Forwarded X11 connection terminated");
3974 assert(c
->u
.x11
.s
!= NULL
);
3975 x11_close(c
->u
.x11
.s
);
3978 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
3979 logevent("Forwarded port closed");
3980 assert(c
->u
.pfd
.s
!= NULL
);
3981 pfd_close(c
->u
.pfd
.s
);
3985 c
->closes
|= (closetype
<< 2); /* seen this message */
3986 if (!(c
->closes
& closetype
)) {
3987 send_packet(ssh
, pktin
->type
, PKT_INT
, c
->remoteid
,
3989 c
->closes
|= closetype
; /* sent it too */
3992 if (c
->closes
== 15) {
3993 del234(ssh
->channels
, c
);
3997 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
3998 pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
3999 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
4003 } else if (pktin
->type
== SSH1_MSG_CHANNEL_DATA
) {
4004 /* Data sent down one of our channels. */
4005 int i
= ssh_pkt_getuint32(pktin
);
4008 struct ssh_channel
*c
;
4010 ssh_pkt_getstring(pktin
, &p
, &len
);
4012 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4017 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
4020 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
4023 /* Data for an agent message. Buffer it. */
4025 if (c
->u
.a
.lensofar
< 4) {
4026 int l
= min(4 - c
->u
.a
.lensofar
, len
);
4027 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
4031 c
->u
.a
.lensofar
+= l
;
4033 if (c
->u
.a
.lensofar
== 4) {
4035 4 + GET_32BIT(c
->u
.a
.msglen
);
4036 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
4038 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
4040 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
4042 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
4044 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
4048 c
->u
.a
.lensofar
+= l
;
4050 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
4053 if (agent_query(c
->u
.a
.message
,
4056 ssh_agentf_callback
, c
))
4057 ssh_agentf_callback(c
, reply
, replylen
);
4058 sfree(c
->u
.a
.message
);
4059 c
->u
.a
.lensofar
= 0;
4062 bufsize
= 0; /* agent channels never back up */
4065 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4066 c
->v
.v1
.throttling
= 1;
4067 ssh1_throttle(ssh
, +1);
4070 } else if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
4071 /* may be from EXEC_SHELL on some servers */
4072 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4073 /* may be from EXEC_SHELL on some servers
4074 * if no pty is available or in other odd cases. Ignore */
4075 } else if (pktin
->type
== SSH1_SMSG_EXIT_STATUS
) {
4077 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
4078 sprintf(buf
, "Server sent command exit status %d",
4081 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
4083 * In case `helpful' firewalls or proxies tack
4084 * extra human-readable text on the end of the
4085 * session which we might mistake for another
4086 * encrypted packet, we close the session once
4087 * we've sent EXIT_CONFIRMATION.
4089 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4092 bombout(("Strange packet received: type %d", pktin
->type
));
4097 int len
= min(inlen
, 512);
4098 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4099 PKT_INT
, len
, PKT_DATA
, in
, len
,
4100 PKTT_OTHER
, PKT_END
);
4111 * Utility routine for decoding comma-separated strings in KEXINIT.
4113 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
4116 if (!needle
|| !haystack
) /* protect against null pointers */
4118 needlen
= strlen(needle
);
4121 * Is it at the start of the string?
4123 if (haylen
>= needlen
&& /* haystack is long enough */
4124 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4125 (haylen
== needlen
|| haystack
[needlen
] == ',')
4126 /* either , or EOS follows */
4130 * If not, search for the next comma and resume after that.
4131 * If no comma found, terminate.
4133 while (haylen
> 0 && *haystack
!= ',')
4134 haylen
--, haystack
++;
4137 haylen
--, haystack
++; /* skip over comma itself */
4142 * SSH2 key creation method.
4144 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
4145 unsigned char *sessid
, char chr
,
4146 unsigned char *keyspace
)
4149 /* First 20 bytes. */
4151 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4153 SHA_Bytes(&s
, H
, 20);
4154 SHA_Bytes(&s
, &chr
, 1);
4155 SHA_Bytes(&s
, sessid
, 20);
4156 SHA_Final(&s
, keyspace
);
4157 /* Next 20 bytes. */
4159 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4161 SHA_Bytes(&s
, H
, 20);
4162 SHA_Bytes(&s
, keyspace
, 20);
4163 SHA_Final(&s
, keyspace
+ 20);
4167 * Handle the SSH2 transport layer.
4169 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
,
4170 struct Packet
*pktin
)
4172 struct do_ssh2_transport_state
{
4173 int nbits
, pbits
, warn
;
4174 Bignum p
, g
, e
, f
, K
;
4175 int kex_init_value
, kex_reply_value
;
4176 const struct ssh_mac
**maclist
;
4178 const struct ssh2_cipher
*cscipher_tobe
;
4179 const struct ssh2_cipher
*sccipher_tobe
;
4180 const struct ssh_mac
*csmac_tobe
;
4181 const struct ssh_mac
*scmac_tobe
;
4182 const struct ssh_compress
*cscomp_tobe
;
4183 const struct ssh_compress
*sccomp_tobe
;
4184 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4185 int hostkeylen
, siglen
;
4186 void *hkey
; /* actual host key */
4187 unsigned char exchange_hash
[20];
4188 int n_preferred_ciphers
;
4189 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
4190 const struct ssh_compress
*preferred_comp
;
4192 struct Packet
*pktout
;
4194 crState(do_ssh2_transport_state
);
4196 crBegin(ssh
->do_ssh2_transport_crstate
);
4198 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
4199 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
4200 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
4208 * Set up the preferred ciphers. (NULL => warn below here)
4210 s
->n_preferred_ciphers
= 0;
4211 for (i
= 0; i
< CIPHER_MAX
; i
++) {
4212 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
4213 case CIPHER_BLOWFISH
:
4214 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
4217 if (ssh
->cfg
.ssh2_des_cbc
) {
4218 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
4222 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
4225 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
4228 /* Flag for later. Don't bother if it's the last in
4230 if (i
< CIPHER_MAX
- 1) {
4231 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
4239 * Set up preferred compression.
4241 if (ssh
->cfg
.compression
)
4242 s
->preferred_comp
= &ssh_zlib
;
4244 s
->preferred_comp
= &ssh_comp_none
;
4247 * Be prepared to work around the buggy MAC problem.
4249 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
4250 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
4252 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
4256 int i
, j
, cipherstr_started
;
4259 * Construct and send our key exchange packet.
4261 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEXINIT
);
4262 for (i
= 0; i
< 16; i
++)
4263 ssh2_pkt_addbyte(s
->pktout
, (unsigned char) random_byte());
4264 /* List key exchange algorithms. */
4265 ssh2_pkt_addstring_start(s
->pktout
);
4266 for (i
= 0; i
< lenof(kex_algs
); i
++) {
4267 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
4268 (ssh
->remote_bugs
& BUG_SSH2_DH_GEX
))
4270 ssh2_pkt_addstring_str(s
->pktout
, kex_algs
[i
]->name
);
4271 if (i
< lenof(kex_algs
) - 1)
4272 ssh2_pkt_addstring_str(s
->pktout
, ",");
4274 /* List server host key algorithms. */
4275 ssh2_pkt_addstring_start(s
->pktout
);
4276 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4277 ssh2_pkt_addstring_str(s
->pktout
, hostkey_algs
[i
]->name
);
4278 if (i
< lenof(hostkey_algs
) - 1)
4279 ssh2_pkt_addstring_str(s
->pktout
, ",");
4281 /* List client->server encryption algorithms. */
4282 ssh2_pkt_addstring_start(s
->pktout
);
4283 cipherstr_started
= 0;
4284 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4285 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4286 if (!c
) continue; /* warning flag */
4287 for (j
= 0; j
< c
->nciphers
; j
++) {
4288 if (cipherstr_started
)
4289 ssh2_pkt_addstring_str(s
->pktout
, ",");
4290 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4291 cipherstr_started
= 1;
4294 /* List server->client encryption algorithms. */
4295 ssh2_pkt_addstring_start(s
->pktout
);
4296 cipherstr_started
= 0;
4297 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4298 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4299 if (!c
) continue; /* warning flag */
4300 for (j
= 0; j
< c
->nciphers
; j
++) {
4301 if (cipherstr_started
)
4302 ssh2_pkt_addstring_str(s
->pktout
, ",");
4303 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4304 cipherstr_started
= 1;
4307 /* List client->server MAC algorithms. */
4308 ssh2_pkt_addstring_start(s
->pktout
);
4309 for (i
= 0; i
< s
->nmacs
; i
++) {
4310 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4311 if (i
< s
->nmacs
- 1)
4312 ssh2_pkt_addstring_str(s
->pktout
, ",");
4314 /* List server->client MAC algorithms. */
4315 ssh2_pkt_addstring_start(s
->pktout
);
4316 for (i
= 0; i
< s
->nmacs
; i
++) {
4317 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4318 if (i
< s
->nmacs
- 1)
4319 ssh2_pkt_addstring_str(s
->pktout
, ",");
4321 /* List client->server compression algorithms. */
4322 ssh2_pkt_addstring_start(s
->pktout
);
4323 assert(lenof(compressions
) > 1);
4324 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4325 for (i
= 0; i
< lenof(compressions
); i
++) {
4326 const struct ssh_compress
*c
= compressions
[i
];
4327 if (c
!= s
->preferred_comp
) {
4328 ssh2_pkt_addstring_str(s
->pktout
, ",");
4329 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4332 /* List server->client compression algorithms. */
4333 ssh2_pkt_addstring_start(s
->pktout
);
4334 assert(lenof(compressions
) > 1);
4335 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4336 for (i
= 0; i
< lenof(compressions
); i
++) {
4337 const struct ssh_compress
*c
= compressions
[i
];
4338 if (c
!= s
->preferred_comp
) {
4339 ssh2_pkt_addstring_str(s
->pktout
, ",");
4340 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4343 /* List client->server languages. Empty list. */
4344 ssh2_pkt_addstring_start(s
->pktout
);
4345 /* List server->client languages. Empty list. */
4346 ssh2_pkt_addstring_start(s
->pktout
);
4347 /* First KEX packet does _not_ follow, because we're not that brave. */
4348 ssh2_pkt_addbool(s
->pktout
, FALSE
);
4350 ssh2_pkt_adduint32(s
->pktout
, 0);
4353 ssh
->exhash
= ssh
->exhashbase
;
4354 sha_string(&ssh
->exhash
, s
->pktout
->data
+ 5, s
->pktout
->length
- 5);
4356 ssh2_pkt_send(ssh
, s
->pktout
);
4360 if (pktin
->length
> 5)
4361 sha_string(&ssh
->exhash
, pktin
->data
+ 5, pktin
->length
- 5);
4364 * Now examine the other side's KEXINIT to see what we're up
4371 if (pktin
->type
!= SSH2_MSG_KEXINIT
) {
4372 bombout(("expected key exchange packet from server"));
4376 ssh
->hostkey
= NULL
;
4377 s
->cscipher_tobe
= NULL
;
4378 s
->sccipher_tobe
= NULL
;
4379 s
->csmac_tobe
= NULL
;
4380 s
->scmac_tobe
= NULL
;
4381 s
->cscomp_tobe
= NULL
;
4382 s
->sccomp_tobe
= NULL
;
4383 pktin
->savedpos
+= 16; /* skip garbage cookie */
4384 ssh_pkt_getstring(pktin
, &str
, &len
); /* key exchange algorithms */
4385 for (i
= 0; i
< lenof(kex_algs
); i
++) {
4386 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
4387 (ssh
->remote_bugs
& BUG_SSH2_DH_GEX
))
4389 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
4390 ssh
->kex
= kex_algs
[i
];
4394 ssh_pkt_getstring(pktin
, &str
, &len
); /* host key algorithms */
4395 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4396 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
4397 ssh
->hostkey
= hostkey_algs
[i
];
4401 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server cipher */
4403 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4404 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4408 for (j
= 0; j
< c
->nciphers
; j
++) {
4409 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4410 s
->cscipher_tobe
= c
->list
[j
];
4415 if (s
->cscipher_tobe
) {
4417 askcipher(ssh
->frontend
, s
->cscipher_tobe
->name
, 1);
4421 if (!s
->cscipher_tobe
) {
4422 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
4423 str ? str
: "(null)"));
4427 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client cipher */
4429 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4430 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4434 for (j
= 0; j
< c
->nciphers
; j
++) {
4435 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4436 s
->sccipher_tobe
= c
->list
[j
];
4441 if (s
->sccipher_tobe
) {
4443 askcipher(ssh
->frontend
, s
->sccipher_tobe
->name
, 2);
4447 if (!s
->sccipher_tobe
) {
4448 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
4449 str ? str
: "(null)"));
4453 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server mac */
4454 for (i
= 0; i
< s
->nmacs
; i
++) {
4455 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4456 s
->csmac_tobe
= s
->maclist
[i
];
4460 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client mac */
4461 for (i
= 0; i
< s
->nmacs
; i
++) {
4462 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4463 s
->scmac_tobe
= s
->maclist
[i
];
4467 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server compression */
4468 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4469 const struct ssh_compress
*c
=
4470 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4471 if (in_commasep_string(c
->name
, str
, len
)) {
4476 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client compression */
4477 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4478 const struct ssh_compress
*c
=
4479 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4480 if (in_commasep_string(c
->name
, str
, len
)) {
4488 * Work out the number of bits of key we will need from the key
4489 * exchange. We start with the maximum key length of either
4495 csbits
= s
->cscipher_tobe
->keylen
;
4496 scbits
= s
->sccipher_tobe
->keylen
;
4497 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
4499 /* The keys only have 160-bit entropy, since they're based on
4500 * a SHA-1 hash. So cap the key size at 160 bits. */
4505 * If we're doing Diffie-Hellman group exchange, start by
4506 * requesting a group.
4508 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4509 logevent("Doing Diffie-Hellman group exchange");
4510 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
4512 * Work out how big a DH group we will need to allow that
4515 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
4516 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
4517 ssh2_pkt_adduint32(s
->pktout
, s
->pbits
);
4518 ssh2_pkt_send(ssh
, s
->pktout
);
4521 if (pktin
->type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
4522 bombout(("expected key exchange group packet from server"));
4525 s
->p
= ssh2_pkt_getmp(pktin
);
4526 s
->g
= ssh2_pkt_getmp(pktin
);
4527 if (!s
->p
|| !s
->g
) {
4528 bombout(("unable to read mp-ints from incoming group packet"));
4531 ssh
->kex_ctx
= dh_setup_group(s
->p
, s
->g
);
4532 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
4533 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
4535 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP1
;
4536 ssh
->kex_ctx
= dh_setup_group1();
4537 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
4538 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
4541 logevent("Doing Diffie-Hellman key exchange");
4543 * Now generate and send e for Diffie-Hellman.
4545 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
4546 s
->pktout
= ssh2_pkt_init(s
->kex_init_value
);
4547 ssh2_pkt_addmp(s
->pktout
, s
->e
);
4548 ssh2_pkt_send(ssh
, s
->pktout
);
4551 if (pktin
->type
!= s
->kex_reply_value
) {
4552 bombout(("expected key exchange reply packet from server"));
4555 ssh_pkt_getstring(pktin
, &s
->hostkeydata
, &s
->hostkeylen
);
4556 s
->f
= ssh2_pkt_getmp(pktin
);
4558 bombout(("unable to parse key exchange reply packet"));
4561 ssh_pkt_getstring(pktin
, &s
->sigdata
, &s
->siglen
);
4563 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
4565 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
4566 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4567 sha_uint32(&ssh
->exhash
, s
->pbits
);
4568 sha_mpint(&ssh
->exhash
, s
->p
);
4569 sha_mpint(&ssh
->exhash
, s
->g
);
4571 sha_mpint(&ssh
->exhash
, s
->e
);
4572 sha_mpint(&ssh
->exhash
, s
->f
);
4573 sha_mpint(&ssh
->exhash
, s
->K
);
4574 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
4576 dh_cleanup(ssh
->kex_ctx
);
4577 ssh
->kex_ctx
= NULL
;
4580 debug(("Exchange hash is:\n"));
4581 dmemdump(s
->exchange_hash
, 20);
4584 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
4586 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
4587 (char *)s
->exchange_hash
, 20)) {
4588 bombout(("Server's host key did not match the signature supplied"));
4593 * Authenticate remote host: verify host key. (We've already
4594 * checked the signature of the exchange hash.)
4596 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
4597 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
4598 verify_ssh_host_key(ssh
->frontend
,
4599 ssh
->savedhost
, ssh
->savedport
, ssh
->hostkey
->keytype
,
4600 s
->keystr
, s
->fingerprint
);
4601 if (s
->first_kex
) { /* don't bother logging this in rekeys */
4602 logevent("Host key fingerprint is:");
4603 logevent(s
->fingerprint
);
4605 sfree(s
->fingerprint
);
4607 ssh
->hostkey
->freekey(s
->hkey
);
4610 * Send SSH2_MSG_NEWKEYS.
4612 s
->pktout
= ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
4613 ssh2_pkt_send(ssh
, s
->pktout
);
4616 * Expect SSH2_MSG_NEWKEYS from server.
4619 if (pktin
->type
!= SSH2_MSG_NEWKEYS
) {
4620 bombout(("expected new-keys packet from server"));
4625 * Create and initialise session keys.
4627 if (ssh
->cs_cipher_ctx
)
4628 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
4629 ssh
->cscipher
= s
->cscipher_tobe
;
4630 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
4632 if (ssh
->sc_cipher_ctx
)
4633 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
4634 ssh
->sccipher
= s
->sccipher_tobe
;
4635 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
4637 if (ssh
->cs_mac_ctx
)
4638 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
4639 ssh
->csmac
= s
->csmac_tobe
;
4640 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
4642 if (ssh
->sc_mac_ctx
)
4643 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
4644 ssh
->scmac
= s
->scmac_tobe
;
4645 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
4647 if (ssh
->cs_comp_ctx
)
4648 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
4649 ssh
->cscomp
= s
->cscomp_tobe
;
4650 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
4652 if (ssh
->sc_comp_ctx
)
4653 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
4654 ssh
->sccomp
= s
->sccomp_tobe
;
4655 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
4658 * Set IVs after keys. Here we use the exchange hash from the
4659 * _first_ key exchange.
4662 unsigned char keyspace
[40];
4664 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
4665 sizeof(s
->exchange_hash
));
4666 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
4667 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
4668 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
4669 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
4670 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
4671 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
4672 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
4673 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
4674 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
4675 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
4676 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
4677 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
4679 logeventf(ssh
, "Initialised %.200s client->server encryption",
4680 ssh
->cscipher
->text_name
);
4681 logeventf(ssh
, "Initialised %.200s server->client encryption",
4682 ssh
->sccipher
->text_name
);
4683 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
4684 ssh
->csmac
->text_name
);
4685 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
4686 ssh
->scmac
->text_name
);
4687 if (ssh
->cscomp
->text_name
)
4688 logeventf(ssh
, "Initialised %s compression",
4689 ssh
->cscomp
->text_name
);
4690 if (ssh
->sccomp
->text_name
)
4691 logeventf(ssh
, "Initialised %s decompression",
4692 ssh
->sccomp
->text_name
);
4695 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4701 * If this is the first key exchange phase, we must pass the
4702 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
4703 * wants to see it but because it will need time to initialise
4704 * itself before it sees an actual packet. In subsequent key
4705 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
4706 * it would only confuse the layer above.
4708 if (!s
->first_kex
) {
4714 * Now we're encrypting. Begin returning 1 to the protocol main
4715 * function so that other things can run on top of the
4716 * transport. If we ever see a KEXINIT, we must go back to the
4719 while (!(pktin
&& pktin
->type
== SSH2_MSG_KEXINIT
)) {
4722 logevent("Server initiated key re-exchange");
4723 goto begin_key_exchange
;
4729 * Add data to an SSH2 channel output buffer.
4731 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
4734 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
4738 * Attempt to send data on an SSH2 channel.
4740 static int ssh2_try_send(struct ssh_channel
*c
)
4743 struct Packet
*pktout
;
4745 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
4748 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
4749 if ((unsigned)len
> c
->v
.v2
.remwindow
)
4750 len
= c
->v
.v2
.remwindow
;
4751 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
4752 len
= c
->v
.v2
.remmaxpkt
;
4753 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
4754 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
4755 dont_log_data(ssh
, pktout
, PKTLOG_OMIT
);
4756 ssh2_pkt_addstring_start(pktout
);
4757 ssh2_pkt_addstring_data(pktout
, data
, len
);
4758 end_log_omission(ssh
, pktout
);
4759 ssh2_pkt_send(ssh
, pktout
);
4760 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
4761 c
->v
.v2
.remwindow
-= len
;
4765 * After having sent as much data as we can, return the amount
4768 return bufchain_size(&c
->v
.v2
.outbuffer
);
4772 * Potentially enlarge the window on an SSH2 channel.
4774 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
4779 * Never send WINDOW_ADJUST for a channel that the remote side
4780 * already thinks it's closed; there's no point, since it won't
4781 * be sending any more data anyway.
4786 if (newwin
> c
->v
.v2
.locwindow
) {
4787 struct Packet
*pktout
;
4789 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4790 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
4791 ssh2_pkt_adduint32(pktout
, newwin
- c
->v
.v2
.locwindow
);
4792 ssh2_pkt_send(ssh
, pktout
);
4793 c
->v
.v2
.locwindow
= newwin
;
4798 * Handle the SSH2 userauth and connection layers.
4800 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
4801 struct Packet
*pktin
)
4803 struct do_ssh2_authconn_state
{
4805 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
4807 AUTH_KEYBOARD_INTERACTIVE
4811 AUTH_TYPE_PUBLICKEY
,
4812 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
4813 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
4815 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
4816 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4818 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
4819 int tried_pubkey_config
, tried_agent
, tried_keyb_inter
;
4820 int kbd_inter_running
;
4822 int num_prompts
, curr_prompt
, echo
;
4827 void *publickey_blob
;
4828 int publickey_bloblen
;
4829 unsigned char request
[5], *response
, *p
;
4833 char *pkblob
, *alg
, *commentp
;
4834 int pklen
, alglen
, commentlen
;
4835 int siglen
, retlen
, len
;
4836 char *q
, *agentreq
, *ret
;
4838 int num_env
, env_left
, env_ok
;
4839 struct Packet
*pktout
;
4841 crState(do_ssh2_authconn_state
);
4843 crBegin(ssh
->do_ssh2_authconn_crstate
);
4846 * Request userauth protocol, and await a response to it.
4848 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
4849 ssh2_pkt_addstring(s
->pktout
, "ssh-userauth");
4850 ssh2_pkt_send(ssh
, s
->pktout
);
4851 crWaitUntilV(pktin
);
4852 if (pktin
->type
!= SSH2_MSG_SERVICE_ACCEPT
) {
4853 bombout(("Server refused user authentication protocol"));
4858 * We repeat this whole loop, including the username prompt,
4859 * until we manage a successful authentication. If the user
4860 * types the wrong _password_, they can be sent back to the
4861 * beginning to try another username, if this is configured on.
4862 * (If they specify a username in the config, they are never
4863 * asked, even if they do give a wrong password.)
4865 * I think this best serves the needs of
4867 * - the people who have no configuration, no keys, and just
4868 * want to try repeated (username,password) pairs until they
4869 * type both correctly
4871 * - people who have keys and configuration but occasionally
4872 * need to fall back to passwords
4874 * - people with a key held in Pageant, who might not have
4875 * logged in to a particular machine before; so they want to
4876 * type a username, and then _either_ their key will be
4877 * accepted, _or_ they will type a password. If they mistype
4878 * the username they will want to be able to get back and
4881 s
->username
[0] = '\0';
4882 s
->got_username
= FALSE
;
4887 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
4889 * We got a username last time round this loop, and
4890 * with change_username turned off we don't try to get
4893 } else if (!*ssh
->cfg
.username
) {
4894 if (ssh_get_line
&& !ssh_getline_pw_only
) {
4895 if (!ssh_get_line("login as: ",
4896 s
->username
, sizeof(s
->username
), FALSE
)) {
4898 * get_line failed to get a username.
4901 logevent("No username provided. Abandoning session.");
4902 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4906 int ret
; /* need not be saved across crReturn */
4907 c_write_str(ssh
, "login as: ");
4909 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
4911 crWaitUntilV(!pktin
);
4912 ret
= process_userpass_input(ssh
, in
, inlen
);
4916 c_write_str(ssh
, "\r\n");
4918 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
4921 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
4922 s
->username
[sizeof(s
->username
)-1] = '\0';
4923 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
4924 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
4925 c_write_str(ssh
, stuff
);
4929 s
->got_username
= TRUE
;
4932 * Send an authentication request using method "none": (a)
4933 * just in case it succeeds, and (b) so that we know what
4934 * authentication methods we can usefully try next.
4936 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4938 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4939 ssh2_pkt_addstring(s
->pktout
, s
->username
);
4940 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");/* service requested */
4941 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
4942 ssh2_pkt_send(ssh
, s
->pktout
);
4943 s
->type
= AUTH_TYPE_NONE
;
4945 s
->we_are_in
= FALSE
;
4947 s
->tried_pubkey_config
= FALSE
;
4948 s
->tried_agent
= FALSE
;
4949 s
->tried_keyb_inter
= FALSE
;
4950 s
->kbd_inter_running
= FALSE
;
4951 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
4952 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
4954 logeventf(ssh
, "Reading private key file \"%.150s\"",
4955 filename_to_str(&ssh
->cfg
.keyfile
));
4956 keytype
= key_type(&ssh
->cfg
.keyfile
);
4957 if (keytype
== SSH_KEYTYPE_SSH2
) {
4959 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
4960 &s
->publickey_bloblen
, NULL
);
4963 logeventf(ssh
, "Unable to use this key file (%s)",
4964 key_type_to_str(keytype
));
4965 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
4967 filename_to_str(&ssh
->cfg
.keyfile
),
4968 key_type_to_str(keytype
));
4969 c_write_str(ssh
, msgbuf
);
4971 s
->publickey_blob
= NULL
;
4974 s
->publickey_blob
= NULL
;
4978 * Wait for the result of the last authentication request.
4981 crWaitUntilV(pktin
);
4982 while (pktin
->type
== SSH2_MSG_USERAUTH_BANNER
) {
4986 * Don't show the banner if we're operating in
4987 * non-verbose non-interactive mode. (It's probably
4988 * a script, which means nobody will read the
4989 * banner _anyway_, and moreover the printing of
4990 * the banner will screw up processing on the
4991 * output of (say) plink.)
4993 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
4994 ssh_pkt_getstring(pktin
, &banner
, &size
);
4996 c_write_untrusted(ssh
, banner
, size
);
4998 crWaitUntilV(pktin
);
5000 if (pktin
->type
== SSH2_MSG_USERAUTH_SUCCESS
) {
5001 logevent("Access granted");
5002 s
->we_are_in
= TRUE
;
5006 if (s
->kbd_inter_running
&&
5007 pktin
->type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
5009 * This is either a further set-of-prompts packet
5010 * in keyboard-interactive authentication, or it's
5011 * the same one and we came back here with `gotit'
5012 * set. In the former case, we must reset the
5013 * curr_prompt variable.
5017 } else if (pktin
->type
!= SSH2_MSG_USERAUTH_FAILURE
) {
5018 bombout(("Strange packet received during authentication: type %d",
5026 * OK, we're now sitting on a USERAUTH_FAILURE message, so
5027 * we can look at the string in it and know what we can
5028 * helpfully try next.
5030 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
) {
5033 ssh_pkt_getstring(pktin
, &methods
, &methlen
);
5034 s
->kbd_inter_running
= FALSE
;
5035 if (!ssh2_pkt_getbool(pktin
)) {
5037 * We have received an unequivocal Access
5038 * Denied. This can translate to a variety of
5041 * - if we'd just tried "none" authentication,
5042 * it's not worth printing anything at all
5044 * - if we'd just tried a public key _offer_,
5045 * the message should be "Server refused our
5046 * key" (or no message at all if the key
5047 * came from Pageant)
5049 * - if we'd just tried anything else, the
5050 * message really should be "Access denied".
5052 * Additionally, if we'd just tried password
5053 * authentication, we should break out of this
5054 * whole loop so as to go back to the username
5055 * prompt (iff we're configured to allow
5056 * username change attempts).
5058 if (s
->type
== AUTH_TYPE_NONE
) {
5060 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
5061 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
5062 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
5063 c_write_str(ssh
, "Server refused our key\r\n");
5064 logevent("Server refused public key");
5065 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
5066 /* server declined keyboard-interactive; ignore */
5068 c_write_str(ssh
, "Access denied\r\n");
5069 logevent("Access denied");
5070 if (s
->type
== AUTH_TYPE_PASSWORD
&&
5071 ssh
->cfg
.change_username
) {
5072 /* XXX perhaps we should allow
5073 * keyboard-interactive to do this too? */
5074 s
->we_are_in
= FALSE
;
5079 c_write_str(ssh
, "Further authentication required\r\n");
5080 logevent("Further authentication required");
5084 in_commasep_string("publickey", methods
, methlen
);
5086 in_commasep_string("password", methods
, methlen
);
5087 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
5088 in_commasep_string("keyboard-interactive", methods
, methlen
);
5092 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5096 * Most password/passphrase prompts will be
5097 * non-echoing, so we set this to 0 by default.
5098 * Exception is that some keyboard-interactive prompts
5099 * can be echoing, in which case we'll set this to 1.
5103 if (!s
->method
&& s
->can_pubkey
&&
5104 agent_exists() && !s
->tried_agent
) {
5106 * Attempt public-key authentication using Pageant.
5111 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5112 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
5114 s
->tried_agent
= TRUE
;
5116 logevent("Pageant is running. Requesting keys.");
5118 /* Request the keys held by the agent. */
5119 PUT_32BIT(s
->request
, 1);
5120 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
5121 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
5122 ssh_agent_callback
, ssh
)) {
5126 bombout(("Unexpected data from server while"
5127 " waiting for agent response"));
5130 } while (pktin
|| inlen
> 0);
5131 r
= ssh
->agent_response
;
5132 s
->responselen
= ssh
->agent_response_len
;
5134 s
->response
= (unsigned char *) r
;
5135 if (s
->response
&& s
->responselen
>= 5 &&
5136 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
5137 s
->p
= s
->response
+ 5;
5138 s
->nkeys
= GET_32BIT(s
->p
);
5142 sprintf(buf
, "Pageant has %d SSH2 keys", s
->nkeys
);
5145 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
5150 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
5153 s
->pklen
= GET_32BIT(s
->p
);
5155 if (s
->publickey_blob
&&
5156 s
->pklen
== s
->publickey_bloblen
&&
5157 !memcmp(s
->p
, s
->publickey_blob
,
5158 s
->publickey_bloblen
)) {
5159 logevent("This key matches configured key file");
5160 s
->tried_pubkey_config
= 1;
5162 s
->pkblob
= (char *)s
->p
;
5164 s
->alglen
= GET_32BIT(s
->pkblob
);
5165 s
->alg
= s
->pkblob
+ 4;
5166 s
->commentlen
= GET_32BIT(s
->p
);
5168 s
->commentp
= (char *)s
->p
;
5169 s
->p
+= s
->commentlen
;
5170 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
5171 ssh2_pkt_addstring(s
->pktout
, s
->username
);
5172 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
5173 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
5174 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
5175 ssh2_pkt_addstring_start(s
->pktout
);
5176 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
5177 ssh2_pkt_addstring_start(s
->pktout
);
5178 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
5179 ssh2_pkt_send(ssh
, s
->pktout
);
5181 crWaitUntilV(pktin
);
5182 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
5183 logevent("Key refused");
5187 if (flags
& FLAG_VERBOSE
) {
5188 c_write_str(ssh
, "Authenticating with "
5190 c_write(ssh
, s
->commentp
, s
->commentlen
);
5191 c_write_str(ssh
, "\" from agent\r\n");
5195 * Server is willing to accept the key.
5196 * Construct a SIGN_REQUEST.
5198 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
5199 ssh2_pkt_addstring(s
->pktout
, s
->username
);
5200 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
5201 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
5202 ssh2_pkt_addbool(s
->pktout
, TRUE
);
5203 ssh2_pkt_addstring_start(s
->pktout
);
5204 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
5205 ssh2_pkt_addstring_start(s
->pktout
);
5206 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
5208 s
->siglen
= s
->pktout
->length
- 5 + 4 + 20;
5209 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
5211 s
->len
= 1; /* message type */
5212 s
->len
+= 4 + s
->pklen
; /* key blob */
5213 s
->len
+= 4 + s
->siglen
; /* data to sign */
5214 s
->len
+= 4; /* flags */
5215 s
->agentreq
= snewn(4 + s
->len
, char);
5216 PUT_32BIT(s
->agentreq
, s
->len
);
5217 s
->q
= s
->agentreq
+ 4;
5218 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
5219 PUT_32BIT(s
->q
, s
->pklen
);
5221 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
5223 PUT_32BIT(s
->q
, s
->siglen
);
5225 /* Now the data to be signed... */
5226 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
5227 PUT_32BIT(s
->q
, 20);
5230 memcpy(s
->q
, ssh
->v2_session_id
, 20);
5232 memcpy(s
->q
, s
->pktout
->data
+ 5,
5233 s
->pktout
->length
- 5);
5234 s
->q
+= s
->pktout
->length
- 5;
5235 /* And finally the (zero) flags word. */
5237 if (!agent_query(s
->agentreq
, s
->len
+ 4,
5239 ssh_agent_callback
, ssh
)) {
5243 bombout(("Unexpected data from server"
5244 " while waiting for agent"
5248 } while (pktin
|| inlen
> 0);
5249 vret
= ssh
->agent_response
;
5250 s
->retlen
= ssh
->agent_response_len
;
5255 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
5256 logevent("Sending Pageant's response");
5257 ssh2_add_sigblob(ssh
, s
->pktout
,
5258 s
->pkblob
, s
->pklen
,
5260 GET_32BIT(s
->ret
+ 5));
5261 ssh2_pkt_send(ssh
, s
->pktout
);
5266 ("Pageant failed to answer challenge");
5277 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
5278 && !s
->tried_pubkey_config
) {
5279 unsigned char *pub_blob
;
5280 char *algorithm
, *comment
;
5283 s
->tried_pubkey_config
= TRUE
;
5285 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5286 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
5289 * Try the public key supplied in the configuration.
5291 * First, offer the public blob to see if the server is
5292 * willing to accept it.
5295 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
5300 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
5301 ssh2_pkt_addstring(s
->pktout
, s
->username
);
5302 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
5303 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
5304 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
5305 ssh2_pkt_addstring(s
->pktout
, algorithm
);
5306 ssh2_pkt_addstring_start(s
->pktout
);
5307 ssh2_pkt_addstring_data(s
->pktout
, (char *)pub_blob
,
5309 ssh2_pkt_send(ssh
, s
->pktout
);
5310 logevent("Offered public key");
5312 crWaitUntilV(pktin
);
5313 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
5315 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
5316 continue; /* key refused; give up on it */
5319 logevent("Offer of public key accepted");
5321 * Actually attempt a serious authentication using
5324 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
5325 sprintf(s
->pwprompt
,
5326 "Passphrase for key \"%.100s\": ",
5332 if (flags
& FLAG_VERBOSE
) {
5333 c_write_str(ssh
, "Authenticating with public key \"");
5334 c_write_str(ssh
, comment
);
5335 c_write_str(ssh
, "\"\r\n");
5337 s
->method
= AUTH_PUBLICKEY_FILE
;
5341 if (!s
->method
&& s
->can_keyb_inter
&& !s
->tried_keyb_inter
) {
5342 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
5343 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
5344 s
->tried_keyb_inter
= TRUE
;
5346 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5347 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
5349 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
5350 ssh2_pkt_addstring(s
->pktout
, s
->username
);
5351 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
5352 ssh2_pkt_addstring(s
->pktout
, "keyboard-interactive"); /* method */
5353 ssh2_pkt_addstring(s
->pktout
, ""); /* lang */
5354 ssh2_pkt_addstring(s
->pktout
, "");
5355 ssh2_pkt_send(ssh
, s
->pktout
);
5357 crWaitUntilV(pktin
);
5358 if (pktin
->type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
5359 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
)
5361 logevent("Keyboard-interactive authentication refused");
5362 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
5366 s
->kbd_inter_running
= TRUE
;
5370 if (s
->kbd_inter_running
) {
5371 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
5372 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
5373 s
->tried_keyb_inter
= TRUE
;
5375 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5376 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
5378 if (s
->curr_prompt
== 0) {
5380 * We've got a fresh USERAUTH_INFO_REQUEST.
5381 * Display header data, and start going through
5384 char *name
, *inst
, *lang
;
5385 int name_len
, inst_len
, lang_len
;
5387 ssh_pkt_getstring(pktin
, &name
, &name_len
);
5388 ssh_pkt_getstring(pktin
, &inst
, &inst_len
);
5389 ssh_pkt_getstring(pktin
, &lang
, &lang_len
);
5391 c_write_untrusted(ssh
, name
, name_len
);
5392 c_write_str(ssh
, "\r\n");
5395 c_write_untrusted(ssh
, inst
, inst_len
);
5396 c_write_str(ssh
, "\r\n");
5398 s
->num_prompts
= ssh_pkt_getuint32(pktin
);
5402 * If there are prompts remaining in the packet,
5403 * display one and get a response.
5405 if (s
->curr_prompt
< s
->num_prompts
) {
5409 ssh_pkt_getstring(pktin
, &prompt
, &prompt_len
);
5410 if (prompt_len
> 0) {
5411 static const char trunc
[] = "<prompt truncated>: ";
5412 static const int prlen
= sizeof(s
->pwprompt
) -
5414 if (prompt_len
> prlen
) {
5415 memcpy(s
->pwprompt
, prompt
, prlen
);
5416 strcpy(s
->pwprompt
+ prlen
, trunc
);
5418 memcpy(s
->pwprompt
, prompt
, prompt_len
);
5419 s
->pwprompt
[prompt_len
] = '\0';
5423 "<server failed to send prompt>: ");
5425 s
->echo
= ssh2_pkt_getbool(pktin
);
5431 if (!s
->method
&& s
->can_passwd
) {
5432 s
->method
= AUTH_PASSWORD
;
5433 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5434 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
5435 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
5442 if (!ssh_get_line(s
->pwprompt
, s
->password
,
5443 sizeof(s
->password
), TRUE
)) {
5445 * get_line failed to get a password (for
5446 * example because one was supplied on the
5447 * command line which has already failed to
5450 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5451 ssh2_pkt_adduint32(s
->pktout
,SSH2_DISCONNECT_BY_APPLICATION
);
5452 ssh2_pkt_addstring(s
->pktout
, "No more passwords available"
5454 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
5455 ssh2_pkt_send(ssh
, s
->pktout
);
5456 logevent("Unable to authenticate");
5457 connection_fatal(ssh
->frontend
,
5458 "Unable to authenticate");
5459 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5463 int ret
; /* need not be saved across crReturn */
5464 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
5467 setup_userpass_input(ssh
, s
->password
,
5468 sizeof(s
->password
), s
->echo
);
5470 crWaitUntilV(!pktin
);
5471 ret
= process_userpass_input(ssh
, in
, inlen
);
5475 c_write_str(ssh
, "\r\n");
5479 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
5481 * We have our passphrase. Now try the actual authentication.
5483 struct ssh2_userkey
*key
;
5484 const char *error
= NULL
;
5486 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
,
5488 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
5489 if (key
== SSH2_WRONG_PASSPHRASE
) {
5490 c_write_str(ssh
, "Wrong passphrase\r\n");
5491 s
->tried_pubkey_config
= FALSE
;
5493 c_write_str(ssh
, "Unable to load private key (");
5494 c_write_str(ssh
, error
);
5495 c_write_str(ssh
, ")\r\n");
5496 s
->tried_pubkey_config
= TRUE
;
5498 /* Send a spurious AUTH_NONE to return to the top. */
5499 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
5500 ssh2_pkt_addstring(s
->pktout
, s
->username
);
5501 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
5502 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
5503 ssh2_pkt_send(ssh
, s
->pktout
);
5504 s
->type
= AUTH_TYPE_NONE
;
5506 unsigned char *pkblob
, *sigblob
, *sigdata
;
5507 int pkblob_len
, sigblob_len
, sigdata_len
;
5511 * We have loaded the private key and the server
5512 * has announced that it's willing to accept it.
5513 * Hallelujah. Generate a signature and send it.
5515 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
5516 ssh2_pkt_addstring(s
->pktout
, s
->username
);
5517 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
5518 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
5519 ssh2_pkt_addbool(s
->pktout
, TRUE
);
5520 ssh2_pkt_addstring(s
->pktout
, key
->alg
->name
);
5521 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
5522 ssh2_pkt_addstring_start(s
->pktout
);
5523 ssh2_pkt_addstring_data(s
->pktout
, (char *)pkblob
, pkblob_len
);
5526 * The data to be signed is:
5530 * followed by everything so far placed in the
5533 sigdata_len
= s
->pktout
->length
- 5 + 4 + 20;
5534 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
5536 sigdata
= snewn(sigdata_len
, unsigned char);
5538 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
5539 PUT_32BIT(sigdata
+p
, 20);
5542 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
5543 memcpy(sigdata
+p
, s
->pktout
->data
+ 5,
5544 s
->pktout
->length
- 5);
5545 p
+= s
->pktout
->length
- 5;
5546 assert(p
== sigdata_len
);
5547 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
5548 sigdata_len
, &sigblob_len
);
5549 ssh2_add_sigblob(ssh
, s
->pktout
, pkblob
, pkblob_len
,
5550 sigblob
, sigblob_len
);
5555 ssh2_pkt_send(ssh
, s
->pktout
);
5556 s
->type
= AUTH_TYPE_PUBLICKEY
;
5557 key
->alg
->freekey(key
->data
);
5559 } else if (s
->method
== AUTH_PASSWORD
) {
5561 * We send the password packet lumped tightly together with
5562 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
5563 * string long enough to make the total length of the two
5564 * packets constant. This should ensure that a passive
5565 * listener doing traffic analyis can't work out the length
5568 * For this to work, we need an assumption about the
5569 * maximum length of the password packet. I think 256 is
5570 * pretty conservative. Anyone using a password longer than
5571 * that probably doesn't have much to worry about from
5572 * people who find out how long their password is!
5574 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
5575 ssh2_pkt_addstring(s
->pktout
, s
->username
);
5576 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
5577 ssh2_pkt_addstring(s
->pktout
, "password");
5578 ssh2_pkt_addbool(s
->pktout
, FALSE
);
5579 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
5580 ssh2_pkt_addstring(s
->pktout
, s
->password
);
5581 memset(s
->password
, 0, sizeof(s
->password
));
5582 end_log_omission(ssh
, s
->pktout
);
5583 ssh2_pkt_defer(ssh
, s
->pktout
);
5585 * We'll include a string that's an exact multiple of the
5586 * cipher block size. If the cipher is NULL for some
5587 * reason, we don't do this trick at all because we gain
5590 if (ssh
->cscipher
) {
5593 stringlen
= (256 - ssh
->deferred_len
);
5594 stringlen
+= ssh
->cscipher
->blksize
- 1;
5595 stringlen
-= (stringlen
% ssh
->cscipher
->blksize
);
5598 * Temporarily disable actual compression,
5599 * so we can guarantee to get this string
5600 * exactly the length we want it. The
5601 * compression-disabling routine should
5602 * return an integer indicating how many
5603 * bytes we should adjust our string length
5607 ssh
->cscomp
->disable_compression(ssh
->cs_comp_ctx
);
5609 s
->pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
5610 ssh2_pkt_addstring_start(s
->pktout
);
5611 for (i
= 0; i
< stringlen
; i
++) {
5612 char c
= (char) random_byte();
5613 ssh2_pkt_addstring_data(s
->pktout
, &c
, 1);
5615 ssh2_pkt_defer(ssh
, s
->pktout
);
5617 ssh_pkt_defersend(ssh
);
5618 logevent("Sent password");
5619 s
->type
= AUTH_TYPE_PASSWORD
;
5620 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
5621 if (s
->curr_prompt
== 0) {
5622 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
5623 ssh2_pkt_adduint32(s
->pktout
, s
->num_prompts
);
5625 if (s
->need_pw
) { /* only add pw if we just got one! */
5626 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
5627 ssh2_pkt_addstring(s
->pktout
, s
->password
);
5628 memset(s
->password
, 0, sizeof(s
->password
));
5629 end_log_omission(ssh
, s
->pktout
);
5632 if (s
->curr_prompt
>= s
->num_prompts
) {
5633 ssh2_pkt_send(ssh
, s
->pktout
);
5636 * If there are prompts remaining, we set
5637 * `gotit' so that we won't attempt to get
5638 * another packet. Then we go back round the
5639 * loop and will end up retrieving another
5640 * prompt out of the existing packet. Funky or
5645 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
5647 c_write_str(ssh
, "No supported authentication methods"
5648 " left to try!\r\n");
5649 logevent("No supported authentications offered."
5651 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5652 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5653 ssh2_pkt_addstring(s
->pktout
, "No supported authentication"
5654 " methods available");
5655 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
5656 ssh2_pkt_send(ssh
, s
->pktout
);
5657 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5661 } while (!s
->we_are_in
);
5664 * Now we're authenticated for the connection protocol. The
5665 * connection protocol will automatically have started at this
5666 * point; there's no need to send SERVICE_REQUEST.
5669 ssh
->channels
= newtree234(ssh_channelcmp
);
5672 * Create the main session channel.
5674 if (!ssh
->cfg
.ssh_no_shell
) {
5675 ssh
->mainchan
= snew(struct ssh_channel
);
5676 ssh
->mainchan
->ssh
= ssh
;
5677 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
5678 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
5679 ssh2_pkt_addstring(s
->pktout
, "session");
5680 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->localid
);
5681 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5682 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
5683 ssh2_pkt_adduint32(s
->pktout
, 0x4000UL
); /* our max pkt size */
5684 ssh2_pkt_send(ssh
, s
->pktout
);
5685 crWaitUntilV(pktin
);
5686 if (pktin
->type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
5687 bombout(("Server refused to open a session"));
5689 /* FIXME: error data comes back in FAILURE packet */
5691 if (ssh_pkt_getuint32(pktin
) != ssh
->mainchan
->localid
) {
5692 bombout(("Server's channel confirmation cited wrong channel"));
5695 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(pktin
);
5696 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
5697 ssh
->mainchan
->closes
= 0;
5698 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
5699 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
5700 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
5701 add234(ssh
->channels
, ssh
->mainchan
);
5702 update_specials_menu(ssh
->frontend
);
5703 logevent("Opened channel for session");
5705 ssh
->mainchan
= NULL
;
5708 * Potentially enable X11 forwarding.
5710 if (ssh
->mainchan
&& ssh
->cfg
.x11_forward
) {
5711 char proto
[20], data
[64];
5712 logevent("Requesting X11 forwarding");
5713 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
5714 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
5715 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
5716 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5717 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
5718 ssh2_pkt_addstring(s
->pktout
, "x11-req");
5719 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
5720 ssh2_pkt_addbool(s
->pktout
, 0); /* many connections */
5721 ssh2_pkt_addstring(s
->pktout
, proto
);
5722 ssh2_pkt_addstring(s
->pktout
, data
);
5723 ssh2_pkt_adduint32(s
->pktout
, x11_get_screen_number(ssh
->cfg
.x11_display
));
5724 ssh2_pkt_send(ssh
, s
->pktout
);
5727 crWaitUntilV(pktin
);
5728 if (pktin
->type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5729 unsigned i
= ssh_pkt_getuint32(pktin
);
5730 struct ssh_channel
*c
;
5731 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5733 continue; /* nonexistent channel */
5734 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
5736 } while (pktin
->type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5738 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5739 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5740 bombout(("Unexpected response to X11 forwarding request:"
5741 " packet type %d", pktin
->type
));
5744 logevent("X11 forwarding refused");
5746 logevent("X11 forwarding enabled");
5747 ssh
->X11_fwd_enabled
= TRUE
;
5752 * Enable port forwardings.
5757 int sport
,dport
,sserv
,dserv
;
5758 char sports
[256], dports
[256], saddr
[256], host
[256];
5760 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
5761 /* Add port forwardings. */
5762 ssh
->portfwd_strptr
= ssh
->cfg
.portfwd
;
5763 while (*ssh
->portfwd_strptr
) {
5764 type
= *ssh
->portfwd_strptr
++;
5767 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= '\t') {
5768 if (*ssh
->portfwd_strptr
== ':') {
5770 * We've seen a colon in the middle of the
5771 * source port number. This means that
5772 * everything we've seen until now is the
5773 * source _address_, so we'll move it into
5774 * saddr and start sports from the beginning
5777 ssh
->portfwd_strptr
++;
5779 strcpy(saddr
, sports
);
5782 if (n
< 255) sports
[n
++] = *ssh
->portfwd_strptr
++;
5786 if (*ssh
->portfwd_strptr
== '\t')
5787 ssh
->portfwd_strptr
++;
5789 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= ':') {
5790 if (n
< 255) host
[n
++] = *ssh
->portfwd_strptr
++;
5793 if (*ssh
->portfwd_strptr
== ':')
5794 ssh
->portfwd_strptr
++;
5796 while (*ssh
->portfwd_strptr
) {
5797 if (n
< 255) dports
[n
++] = *ssh
->portfwd_strptr
++;
5800 ssh
->portfwd_strptr
++;
5801 dport
= atoi(dports
);
5805 dport
= net_service_lookup(dports
);
5807 logeventf(ssh
, "Service lookup failed for destination"
5808 " port \"%s\"", dports
);
5812 while (*ssh
->portfwd_strptr
) ssh
->portfwd_strptr
++;
5814 ssh
->portfwd_strptr
++; /* eat the NUL and move to next one */
5816 sport
= atoi(sports
);
5820 sport
= net_service_lookup(sports
);
5822 logeventf(ssh
, "Service lookup failed for source"
5823 " port \"%s\"", sports
);
5826 if (sport
&& dport
) {
5827 /* Set up a description of the source port. */
5828 static char *sportdesc
;
5829 sportdesc
= dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
5830 (int)(*saddr?
strlen(saddr
):0), *saddr?saddr
:NULL
,
5831 (int)(*saddr?
1:0), ":",
5832 (int)(sserv ?
strlen(sports
) : 0), sports
,
5833 sserv
, "(", sport
, sserv
, ")");
5835 /* Verbose description of the destination port */
5836 char *dportdesc
= dupprintf("%s:%.*s%.*s%d%.*s",
5838 (int)(dserv ?
strlen(dports
) : 0), dports
,
5839 dserv
, "(", dport
, dserv
, ")");
5840 const char *err
= pfd_addforward(host
, dport
,
5841 *saddr ? saddr
: NULL
,
5842 sport
, ssh
, &ssh
->cfg
);
5844 logeventf(ssh
, "Local port %s forward to %s"
5845 " failed: %s", sportdesc
, dportdesc
, err
);
5847 logeventf(ssh
, "Local port %s forwarding to %s",
5848 sportdesc
, dportdesc
);
5851 } else if (type
== 'D') {
5852 const char *err
= pfd_addforward(NULL
, -1,
5853 *saddr ? saddr
: NULL
,
5854 sport
, ssh
, &ssh
->cfg
);
5856 logeventf(ssh
, "Local port %s SOCKS dynamic forward"
5857 " setup failed: %s", sportdesc
, err
);
5859 logeventf(ssh
, "Local port %s doing SOCKS"
5860 " dynamic forwarding", sportdesc
);
5863 struct ssh_rportfwd
*pf
;
5864 pf
= snew(struct ssh_rportfwd
);
5865 strcpy(pf
->dhost
, host
);
5868 if (add234(ssh
->rportfwds
, pf
) != pf
) {
5869 logeventf(ssh
, "Duplicate remote port forwarding"
5870 " to %s:%d", host
, dport
);
5873 logeventf(ssh
, "Requesting remote port %s"
5874 " forward to %s:%.*s%.*s%d%.*s",
5877 (int)(dserv ?
strlen(dports
) : 0), dports
,
5878 dserv
, "(", dport
, dserv
, ")");
5879 s
->pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
5880 ssh2_pkt_addstring(s
->pktout
, "tcpip-forward");
5881 ssh2_pkt_addbool(s
->pktout
, 1);/* want reply */
5883 ssh2_pkt_addstring(s
->pktout
, saddr
);
5884 } else if (ssh
->cfg
.rport_acceptall
) {
5885 ssh2_pkt_addstring(s
->pktout
, "0.0.0.0");
5887 ssh2_pkt_addstring(s
->pktout
, "127.0.0.1");
5889 ssh2_pkt_adduint32(s
->pktout
, sport
);
5890 ssh2_pkt_send(ssh
, s
->pktout
);
5893 crWaitUntilV(pktin
);
5894 if (pktin
->type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5895 unsigned i
= ssh_pkt_getuint32(pktin
);
5896 struct ssh_channel
*c
;
5897 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5899 continue;/* nonexistent channel */
5900 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
5902 } while (pktin
->type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5904 if (pktin
->type
!= SSH2_MSG_REQUEST_SUCCESS
) {
5905 if (pktin
->type
!= SSH2_MSG_REQUEST_FAILURE
) {
5906 bombout(("Unexpected response to port "
5907 "forwarding request: packet type %d",
5911 logevent("Server refused this port forwarding");
5913 logevent("Remote port forwarding enabled");
5923 * Potentially enable agent forwarding.
5925 if (ssh
->mainchan
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
5926 logevent("Requesting OpenSSH-style agent forwarding");
5927 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5928 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
5929 ssh2_pkt_addstring(s
->pktout
, "auth-agent-req@openssh.com");
5930 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
5931 ssh2_pkt_send(ssh
, s
->pktout
);
5934 crWaitUntilV(pktin
);
5935 if (pktin
->type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5936 unsigned i
= ssh_pkt_getuint32(pktin
);
5937 struct ssh_channel
*c
;
5938 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5940 continue; /* nonexistent channel */
5941 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
5943 } while (pktin
->type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5945 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5946 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5947 bombout(("Unexpected response to agent forwarding request:"
5948 " packet type %d", pktin
->type
));
5951 logevent("Agent forwarding refused");
5953 logevent("Agent forwarding enabled");
5954 ssh
->agentfwd_enabled
= TRUE
;
5959 * Now allocate a pty for the session.
5961 if (ssh
->mainchan
&& !ssh
->cfg
.nopty
) {
5962 /* Unpick the terminal-speed string. */
5963 /* XXX perhaps we should allow no speeds to be sent. */
5964 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
5965 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
5966 /* Build the pty request. */
5967 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5968 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
5969 ssh2_pkt_addstring(s
->pktout
, "pty-req");
5970 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
5971 ssh2_pkt_addstring(s
->pktout
, ssh
->cfg
.termtype
);
5972 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_width
);
5973 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_height
);
5974 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel width */
5975 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel height */
5976 ssh2_pkt_addstring_start(s
->pktout
);
5977 ssh2_pkt_addbyte(s
->pktout
, 128); /* TTY_OP_ISPEED */
5978 ssh2_pkt_adduint32(s
->pktout
, ssh
->ispeed
);
5979 ssh2_pkt_addbyte(s
->pktout
, 129); /* TTY_OP_OSPEED */
5980 ssh2_pkt_adduint32(s
->pktout
, ssh
->ospeed
);
5981 ssh2_pkt_addstring_data(s
->pktout
, "\0", 1); /* TTY_OP_END */
5982 ssh2_pkt_send(ssh
, s
->pktout
);
5983 ssh
->state
= SSH_STATE_INTERMED
;
5986 crWaitUntilV(pktin
);
5987 if (pktin
->type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5988 unsigned i
= ssh_pkt_getuint32(pktin
);
5989 struct ssh_channel
*c
;
5990 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5992 continue; /* nonexistent channel */
5993 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
5995 } while (pktin
->type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5997 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5998 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5999 bombout(("Unexpected response to pty request:"
6000 " packet type %d", pktin
->type
));
6003 c_write_str(ssh
, "Server refused to allocate pty\r\n");
6004 ssh
->editing
= ssh
->echoing
= 1;
6006 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
6007 ssh
->ospeed
, ssh
->ispeed
);
6010 ssh
->editing
= ssh
->echoing
= 1;
6014 * Send environment variables.
6016 * Simplest thing here is to send all the requests at once, and
6017 * then wait for a whole bunch of successes or failures.
6019 if (ssh
->mainchan
&& *ssh
->cfg
.environmt
) {
6020 char *e
= ssh
->cfg
.environmt
;
6021 char *var
, *varend
, *val
;
6027 while (*e
&& *e
!= '\t') e
++;
6029 if (*e
== '\t') e
++;
6034 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6035 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6036 ssh2_pkt_addstring(s
->pktout
, "env");
6037 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6038 ssh2_pkt_addstring_start(s
->pktout
);
6039 ssh2_pkt_addstring_data(s
->pktout
, var
, varend
-var
);
6040 ssh2_pkt_addstring(s
->pktout
, val
);
6041 ssh2_pkt_send(ssh
, s
->pktout
);
6046 logeventf(ssh
, "Sent %d environment variables", s
->num_env
);
6049 s
->env_left
= s
->num_env
;
6051 while (s
->env_left
> 0) {
6053 crWaitUntilV(pktin
);
6054 if (pktin
->type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
6055 unsigned i
= ssh_pkt_getuint32(pktin
);
6056 struct ssh_channel
*c
;
6057 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6059 continue; /* nonexistent channel */
6060 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
6062 } while (pktin
->type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
6064 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6065 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6066 bombout(("Unexpected response to environment request:"
6067 " packet type %d", pktin
->type
));
6077 if (s
->env_ok
== s
->num_env
) {
6078 logevent("All environment variables successfully set");
6079 } else if (s
->env_ok
== 0) {
6080 logevent("All environment variables refused");
6081 c_write_str(ssh
, "Server refused to set environment variables\r\n");
6083 logeventf(ssh
, "%d environment variables refused",
6084 s
->num_env
- s
->env_ok
);
6085 c_write_str(ssh
, "Server refused to set all environment variables\r\n");
6090 * Start a shell or a remote command. We may have to attempt
6091 * this twice if the config data has provided a second choice
6094 if (ssh
->mainchan
) while (1) {
6098 if (ssh
->fallback_cmd
) {
6099 subsys
= ssh
->cfg
.ssh_subsys2
;
6100 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
6102 subsys
= ssh
->cfg
.ssh_subsys
;
6103 cmd
= ssh
->cfg
.remote_cmd_ptr
;
6106 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6107 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
6109 ssh2_pkt_addstring(s
->pktout
, "subsystem");
6110 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6111 ssh2_pkt_addstring(s
->pktout
, cmd
);
6113 ssh2_pkt_addstring(s
->pktout
, "exec");
6114 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6115 ssh2_pkt_addstring(s
->pktout
, cmd
);
6117 ssh2_pkt_addstring(s
->pktout
, "shell");
6118 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6120 ssh2_pkt_send(ssh
, s
->pktout
);
6122 crWaitUntilV(pktin
);
6123 if (pktin
->type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
6124 unsigned i
= ssh_pkt_getuint32(pktin
);
6125 struct ssh_channel
*c
;
6126 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6128 continue; /* nonexistent channel */
6129 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
6131 } while (pktin
->type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
6132 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6133 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6134 bombout(("Unexpected response to shell/command request:"
6135 " packet type %d", pktin
->type
));
6139 * We failed to start the command. If this is the
6140 * fallback command, we really are finished; if it's
6141 * not, and if the fallback command exists, try falling
6142 * back to it before complaining.
6144 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
6145 logevent("Primary command failed; attempting fallback");
6146 ssh
->fallback_cmd
= TRUE
;
6149 bombout(("Server refused to start a shell/command"));
6152 logevent("Started a shell/command");
6157 ssh
->state
= SSH_STATE_SESSION
;
6158 if (ssh
->size_needed
)
6159 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
6160 if (ssh
->eof_needed
)
6161 ssh_special(ssh
, TS_EOF
);
6167 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
6172 s
->try_send
= FALSE
;
6174 if (pktin
->type
== SSH2_MSG_CHANNEL_DATA
||
6175 pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
6178 unsigned i
= ssh_pkt_getuint32(pktin
);
6179 struct ssh_channel
*c
;
6180 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6182 continue; /* nonexistent channel */
6183 if (pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
6184 ssh_pkt_getuint32(pktin
) != SSH2_EXTENDED_DATA_STDERR
)
6185 continue; /* extended but not stderr */
6186 ssh_pkt_getstring(pktin
, &data
, &length
);
6189 c
->v
.v2
.locwindow
-= length
;
6191 case CHAN_MAINSESSION
:
6193 from_backend(ssh
->frontend
, pktin
->type
==
6194 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
6198 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
6201 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
6204 while (length
> 0) {
6205 if (c
->u
.a
.lensofar
< 4) {
6206 int l
= min(4 - c
->u
.a
.lensofar
, length
);
6207 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
6211 c
->u
.a
.lensofar
+= l
;
6213 if (c
->u
.a
.lensofar
== 4) {
6215 4 + GET_32BIT(c
->u
.a
.msglen
);
6216 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
6218 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
6220 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
6222 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
6224 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
6228 c
->u
.a
.lensofar
+= l
;
6230 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
6233 if (agent_query(c
->u
.a
.message
,
6236 ssh_agentf_callback
, c
))
6237 ssh_agentf_callback(c
, reply
, replylen
);
6238 sfree(c
->u
.a
.message
);
6239 c
->u
.a
.lensofar
= 0;
6246 * If we are not buffering too much data,
6247 * enlarge the window again at the remote side.
6249 if (bufsize
< OUR_V2_WINSIZE
)
6250 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
6252 } else if (pktin
->type
== SSH2_MSG_CHANNEL_EOF
) {
6253 unsigned i
= ssh_pkt_getuint32(pktin
);
6254 struct ssh_channel
*c
;
6256 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6258 continue; /* nonexistent channel */
6260 if (c
->type
== CHAN_X11
) {
6262 * Remote EOF on an X11 channel means we should
6263 * wrap up and close the channel ourselves.
6265 x11_close(c
->u
.x11
.s
);
6267 } else if (c
->type
== CHAN_AGENT
) {
6269 } else if (c
->type
== CHAN_SOCKDATA
) {
6270 pfd_close(c
->u
.pfd
.s
);
6273 } else if (pktin
->type
== SSH2_MSG_CHANNEL_CLOSE
) {
6274 unsigned i
= ssh_pkt_getuint32(pktin
);
6275 struct ssh_channel
*c
;
6277 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6278 if (!c
|| ((int)c
->remoteid
) == -1) {
6279 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
6280 c ?
"half-open" : "nonexistent", i
));
6283 /* Do pre-close processing on the channel. */
6285 case CHAN_MAINSESSION
:
6286 ssh
->mainchan
= NULL
;
6287 update_specials_menu(ssh
->frontend
);
6290 if (c
->u
.x11
.s
!= NULL
)
6291 x11_close(c
->u
.x11
.s
);
6298 if (c
->u
.pfd
.s
!= NULL
)
6299 pfd_close(c
->u
.pfd
.s
);
6303 if (c
->closes
== 0) {
6304 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
6305 ssh2_pkt_adduint32(s
->pktout
, c
->remoteid
);
6306 ssh2_pkt_send(ssh
, s
->pktout
);
6308 del234(ssh
->channels
, c
);
6309 bufchain_clear(&c
->v
.v2
.outbuffer
);
6313 * See if that was the last channel left open.
6314 * (This is only our termination condition if we're
6315 * not running in -N mode.)
6317 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
6318 logevent("All channels closed. Disconnecting");
6321 * We used to send SSH_MSG_DISCONNECT here,
6322 * because I'd believed that _every_ conforming
6323 * SSH2 connection had to end with a disconnect
6324 * being sent by at least one side; apparently
6325 * I was wrong and it's perfectly OK to
6326 * unceremoniously slam the connection shut
6327 * when you're done, and indeed OpenSSH feels
6328 * this is more polite than sending a
6329 * DISCONNECT. So now we don't.
6331 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6332 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
6333 ssh2_pkt_addstring(s
->pktout
, "All open channels closed");
6334 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6335 ssh2_pkt_send(ssh
, s
->pktout
);
6337 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6340 continue; /* remote sends close; ignore (FIXME) */
6341 } else if (pktin
->type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
6342 unsigned i
= ssh_pkt_getuint32(pktin
);
6343 struct ssh_channel
*c
;
6344 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6345 if (!c
|| c
->closes
)
6346 continue; /* nonexistent or closing channel */
6347 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
6349 } else if (pktin
->type
== SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
6350 unsigned i
= ssh_pkt_getuint32(pktin
);
6351 struct ssh_channel
*c
;
6352 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6354 continue; /* nonexistent channel */
6355 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
6356 continue; /* dunno why they're confirming this */
6357 c
->remoteid
= ssh_pkt_getuint32(pktin
);
6358 c
->type
= CHAN_SOCKDATA
;
6359 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
6360 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
6362 pfd_confirm(c
->u
.pfd
.s
);
6365 * We have a pending close on this channel,
6366 * which we decided on before the server acked
6367 * the channel open. So now we know the
6368 * remoteid, we can close it again.
6370 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
6371 ssh2_pkt_adduint32(s
->pktout
, c
->remoteid
);
6372 ssh2_pkt_send(ssh
, s
->pktout
);
6374 } else if (pktin
->type
== SSH2_MSG_CHANNEL_OPEN_FAILURE
) {
6375 static const char *const reasons
[] = {
6376 "<unknown reason code>",
6377 "Administratively prohibited",
6379 "Unknown channel type",
6380 "Resource shortage",
6382 unsigned i
= ssh_pkt_getuint32(pktin
);
6383 unsigned reason_code
;
6384 char *reason_string
;
6387 struct ssh_channel
*c
;
6388 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6390 continue; /* nonexistent channel */
6391 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
6392 continue; /* dunno why they're failing this */
6394 reason_code
= ssh_pkt_getuint32(pktin
);
6395 if (reason_code
>= lenof(reasons
))
6396 reason_code
= 0; /* ensure reasons[reason_code] in range */
6397 ssh_pkt_getstring(pktin
, &reason_string
, &reason_length
);
6398 message
= dupprintf("Forwarded connection refused by"
6399 " server: %s [%.*s]", reasons
[reason_code
],
6400 reason_length
, reason_string
);
6404 pfd_close(c
->u
.pfd
.s
);
6406 del234(ssh
->channels
, c
);
6408 } else if (pktin
->type
== SSH2_MSG_CHANNEL_REQUEST
) {
6411 int typelen
, want_reply
;
6412 int reply
= SSH2_MSG_CHANNEL_FAILURE
; /* default */
6413 struct ssh_channel
*c
;
6415 localid
= ssh_pkt_getuint32(pktin
);
6416 ssh_pkt_getstring(pktin
, &type
, &typelen
);
6417 want_reply
= ssh2_pkt_getbool(pktin
);
6420 * First, check that the channel exists. Otherwise,
6421 * we can instantly disconnect with a rude message.
6423 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
6426 sprintf(buf
, "Received channel request for nonexistent"
6427 " channel %d", localid
);
6429 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6430 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
6431 ssh2_pkt_addstring(s
->pktout
, buf
);
6432 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6433 ssh2_pkt_send(ssh
, s
->pktout
);
6434 connection_fatal(ssh
->frontend
, "%s", buf
);
6435 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6440 * Having got the channel number, we now look at
6441 * the request type string to see if it's something
6444 if (c
== ssh
->mainchan
) {
6446 * We recognise "exit-status" and "exit-signal" on
6447 * the primary channel.
6449 if (typelen
== 11 &&
6450 !memcmp(type
, "exit-status", 11)) {
6452 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
6453 logeventf(ssh
, "Server sent command exit status %d",
6455 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
6457 } else if (typelen
== 11 &&
6458 !memcmp(type
, "exit-signal", 11)) {
6460 int is_plausible
= TRUE
, is_int
= FALSE
;
6461 char *fmt_sig
= "", *fmt_msg
= "";
6463 int msglen
= 0, core
= FALSE
;
6464 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
6465 * provide an `int' for the signal, despite its
6466 * having been a `string' in the drafts since at
6467 * least 2001. (Fixed in session.c 1.147.) Try to
6468 * infer which we can safely parse it as. */
6470 unsigned char *p
= pktin
->body
+
6472 long len
= pktin
->length
- pktin
->savedpos
;
6473 unsigned long num
= GET_32BIT(p
); /* what is it? */
6474 /* If it's 0, it hardly matters; assume string */
6478 int maybe_int
= FALSE
, maybe_str
= FALSE
;
6479 #define CHECK_HYPOTHESIS(offset, result) \
6482 if (q >= 0 && q+4 <= len) { \
6483 q = q + 4 + GET_32BIT(p+q); \
6484 if (q >= 0 && q+4 <= len && \
6485 (q = q + 4 + GET_32BIT(p+q)) && q == len) \
6489 CHECK_HYPOTHESIS(4+1, maybe_int
);
6490 CHECK_HYPOTHESIS(4+num
+1, maybe_str
);
6491 #undef CHECK_HYPOTHESIS
6492 if (maybe_int
&& !maybe_str
)
6494 else if (!maybe_int
&& maybe_str
)
6497 /* Crikey. Either or neither. Panic. */
6498 is_plausible
= FALSE
;
6503 /* Old non-standard OpenSSH. */
6504 int signum
= ssh_pkt_getuint32(pktin
);
6505 fmt_sig
= dupprintf(" %d", signum
);
6507 /* As per the drafts. */
6510 ssh_pkt_getstring(pktin
, &sig
, &siglen
);
6511 /* Signal name isn't supposed to be blank, but
6512 * let's cope gracefully if it is. */
6514 fmt_sig
= dupprintf(" \"%.*s\"",
6518 core
= ssh2_pkt_getbool(pktin
);
6519 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
6521 fmt_msg
= dupprintf(" (\"%.*s\")", msglen
, msg
);
6523 /* ignore lang tag */
6524 } /* else don't attempt to parse */
6525 logeventf(ssh
, "Server exited on signal%s%s%s",
6526 fmt_sig
, core ?
" (core dumped)" : "",
6528 if (*fmt_sig
) sfree(fmt_sig
);
6529 if (*fmt_msg
) sfree(fmt_msg
);
6530 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
6535 * This is a channel request we don't know
6536 * about, so we now either ignore the request
6537 * or respond with CHANNEL_FAILURE, depending
6540 reply
= SSH2_MSG_CHANNEL_FAILURE
;
6543 s
->pktout
= ssh2_pkt_init(reply
);
6544 ssh2_pkt_adduint32(s
->pktout
, c
->remoteid
);
6545 ssh2_pkt_send(ssh
, s
->pktout
);
6547 } else if (pktin
->type
== SSH2_MSG_GLOBAL_REQUEST
) {
6549 int typelen
, want_reply
;
6551 ssh_pkt_getstring(pktin
, &type
, &typelen
);
6552 want_reply
= ssh2_pkt_getbool(pktin
);
6555 * We currently don't support any global requests
6556 * at all, so we either ignore the request or
6557 * respond with REQUEST_FAILURE, depending on
6561 s
->pktout
= ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
6562 ssh2_pkt_send(ssh
, s
->pktout
);
6564 } else if (pktin
->type
== SSH2_MSG_CHANNEL_OPEN
) {
6571 struct ssh_channel
*c
;
6572 unsigned remid
, winsize
, pktsize
;
6573 ssh_pkt_getstring(pktin
, &type
, &typelen
);
6574 c
= snew(struct ssh_channel
);
6577 remid
= ssh_pkt_getuint32(pktin
);
6578 winsize
= ssh_pkt_getuint32(pktin
);
6579 pktsize
= ssh_pkt_getuint32(pktin
);
6581 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
6584 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
6585 addrstr
= snewn(peeraddrlen
+1, char);
6586 memcpy(addrstr
, peeraddr
, peeraddrlen
);
6587 addrstr
[peeraddrlen
] = '\0';
6588 peerport
= ssh_pkt_getuint32(pktin
);
6590 logeventf(ssh
, "Received X11 connect request from %s:%d",
6593 if (!ssh
->X11_fwd_enabled
)
6594 error
= "X11 forwarding is not enabled";
6595 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
6596 ssh
->x11auth
, addrstr
, peerport
,
6597 &ssh
->cfg
) != NULL
) {
6598 error
= "Unable to open an X11 connection";
6600 logevent("Opening X11 forward connection succeeded");
6605 } else if (typelen
== 15 &&
6606 !memcmp(type
, "forwarded-tcpip", 15)) {
6607 struct ssh_rportfwd pf
, *realpf
;
6610 ssh_pkt_getstring(pktin
, &dummy
, &dummylen
);/* skip address */
6611 pf
.sport
= ssh_pkt_getuint32(pktin
);
6612 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
6613 peerport
= ssh_pkt_getuint32(pktin
);
6614 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
6615 logeventf(ssh
, "Received remote port %d open request "
6616 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
6617 if (realpf
== NULL
) {
6618 error
= "Remote port is not recognised";
6620 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
6624 logeventf(ssh
, "Attempting to forward remote port to "
6625 "%s:%d", realpf
->dhost
, realpf
->dport
);
6627 logeventf(ssh
, "Port open failed: %s", e
);
6628 error
= "Port open failed";
6630 logevent("Forwarded port opened successfully");
6631 c
->type
= CHAN_SOCKDATA
;
6634 } else if (typelen
== 22 &&
6635 !memcmp(type
, "auth-agent@openssh.com", 3)) {
6636 if (!ssh
->agentfwd_enabled
)
6637 error
= "Agent forwarding is not enabled";
6639 c
->type
= CHAN_AGENT
; /* identify channel type */
6640 c
->u
.a
.lensofar
= 0;
6643 error
= "Unsupported channel type requested";
6646 c
->remoteid
= remid
;
6648 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
6649 ssh2_pkt_adduint32(s
->pktout
, c
->remoteid
);
6650 ssh2_pkt_adduint32(s
->pktout
, SSH2_OPEN_CONNECT_FAILED
);
6651 ssh2_pkt_addstring(s
->pktout
, error
);
6652 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6653 ssh2_pkt_send(ssh
, s
->pktout
);
6654 logeventf(ssh
, "Rejected channel open: %s", error
);
6657 c
->localid
= alloc_channel_id(ssh
);
6659 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6660 c
->v
.v2
.remwindow
= winsize
;
6661 c
->v
.v2
.remmaxpkt
= pktsize
;
6662 bufchain_init(&c
->v
.v2
.outbuffer
);
6663 add234(ssh
->channels
, c
);
6664 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
6665 ssh2_pkt_adduint32(s
->pktout
, c
->remoteid
);
6666 ssh2_pkt_adduint32(s
->pktout
, c
->localid
);
6667 ssh2_pkt_adduint32(s
->pktout
, c
->v
.v2
.locwindow
);
6668 ssh2_pkt_adduint32(s
->pktout
, 0x4000UL
); /* our max pkt size */
6669 ssh2_pkt_send(ssh
, s
->pktout
);
6672 bombout(("Strange packet received: type %d", pktin
->type
));
6675 } else if (ssh
->mainchan
) {
6677 * We have spare data. Add it to the channel buffer.
6679 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
6684 struct ssh_channel
*c
;
6686 * Try to send data on all channels if we can.
6688 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
6691 continue; /* don't send on closing channels */
6692 bufsize
= ssh2_try_send(c
);
6695 case CHAN_MAINSESSION
:
6696 /* stdin need not receive an unthrottle
6697 * notification since it will be polled */
6700 x11_unthrottle(c
->u
.x11
.s
);
6703 /* agent sockets are request/response and need no
6704 * buffer management */
6707 pfd_unthrottle(c
->u
.pfd
.s
);
6719 * Handle the top-level SSH2 protocol.
6721 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
6722 struct Packet
*pktin
)
6724 if (do_ssh2_transport(ssh
, in
, inlen
, pktin
) == 0)
6726 do_ssh2_authconn(ssh
, in
, inlen
, pktin
);
6730 * Called to set up the connection.
6732 * Returns an error message, or NULL on success.
6734 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
6736 char *host
, int port
, char **realhost
, int nodelay
,
6742 ssh
= snew(struct ssh_tag
);
6743 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
6744 ssh
->version
= 0; /* when not ready yet */
6747 ssh
->v1_cipher_ctx
= NULL
;
6748 ssh
->crcda_ctx
= NULL
;
6749 ssh
->cscipher
= NULL
;
6750 ssh
->cs_cipher_ctx
= NULL
;
6751 ssh
->sccipher
= NULL
;
6752 ssh
->sc_cipher_ctx
= NULL
;
6754 ssh
->cs_mac_ctx
= NULL
;
6756 ssh
->sc_mac_ctx
= NULL
;
6758 ssh
->cs_comp_ctx
= NULL
;
6760 ssh
->sc_comp_ctx
= NULL
;
6762 ssh
->kex_ctx
= NULL
;
6763 ssh
->hostkey
= NULL
;
6765 ssh
->state
= SSH_STATE_PREPACKET
;
6766 ssh
->size_needed
= FALSE
;
6767 ssh
->eof_needed
= FALSE
;
6770 ssh
->deferred_send_data
= NULL
;
6771 ssh
->deferred_len
= 0;
6772 ssh
->deferred_size
= 0;
6773 ssh
->fallback_cmd
= 0;
6775 ssh
->x11auth
= NULL
;
6776 ssh
->v1_compressing
= FALSE
;
6777 ssh
->v2_outgoing_sequence
= 0;
6778 ssh
->ssh1_rdpkt_crstate
= 0;
6779 ssh
->ssh2_rdpkt_crstate
= 0;
6780 ssh
->do_ssh_init_crstate
= 0;
6781 ssh
->ssh_gotdata_crstate
= 0;
6782 ssh
->ssh1_protocol_crstate
= 0;
6783 ssh
->do_ssh1_login_crstate
= 0;
6784 ssh
->do_ssh2_transport_crstate
= 0;
6785 ssh
->do_ssh2_authconn_crstate
= 0;
6786 ssh
->do_ssh_init_state
= NULL
;
6787 ssh
->do_ssh1_login_state
= NULL
;
6788 ssh
->do_ssh2_transport_state
= NULL
;
6789 ssh
->do_ssh2_authconn_state
= NULL
;
6790 ssh
->mainchan
= NULL
;
6791 ssh
->throttled_all
= 0;
6792 ssh
->v1_stdout_throttling
= 0;
6794 *backend_handle
= ssh
;
6797 if (crypto_startup() == 0)
6798 return "Microsoft high encryption pack not installed!";
6801 ssh
->frontend
= frontend_handle
;
6802 ssh
->term_width
= ssh
->cfg
.width
;
6803 ssh
->term_height
= ssh
->cfg
.height
;
6805 ssh
->channels
= NULL
;
6806 ssh
->rportfwds
= NULL
;
6811 ssh
->v1_throttle_count
= 0;
6812 ssh
->overall_bufsize
= 0;
6813 ssh
->fallback_cmd
= 0;
6815 ssh
->protocol
= NULL
;
6817 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
6824 static void ssh_free(void *handle
)
6826 Ssh ssh
= (Ssh
) handle
;
6827 struct ssh_channel
*c
;
6828 struct ssh_rportfwd
*pf
;
6830 if (ssh
->v1_cipher_ctx
)
6831 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
6832 if (ssh
->cs_cipher_ctx
)
6833 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
6834 if (ssh
->sc_cipher_ctx
)
6835 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
6836 if (ssh
->cs_mac_ctx
)
6837 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
6838 if (ssh
->sc_mac_ctx
)
6839 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
6840 if (ssh
->cs_comp_ctx
) {
6842 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
6844 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
6846 if (ssh
->sc_comp_ctx
) {
6848 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
6850 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
6853 dh_cleanup(ssh
->kex_ctx
);
6854 sfree(ssh
->savedhost
);
6856 if (ssh
->channels
) {
6857 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
6860 if (c
->u
.x11
.s
!= NULL
)
6861 x11_close(c
->u
.x11
.s
);
6864 if (c
->u
.pfd
.s
!= NULL
)
6865 pfd_close(c
->u
.pfd
.s
);
6870 freetree234(ssh
->channels
);
6873 if (ssh
->rportfwds
) {
6874 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
6876 freetree234(ssh
->rportfwds
);
6878 sfree(ssh
->deferred_send_data
);
6880 x11_free_auth(ssh
->x11auth
);
6881 sfree(ssh
->do_ssh_init_state
);
6882 sfree(ssh
->do_ssh1_login_state
);
6883 sfree(ssh
->do_ssh2_transport_state
);
6884 sfree(ssh
->do_ssh2_authconn_state
);
6885 if (ssh
->crcda_ctx
) {
6886 crcda_free_context(ssh
->crcda_ctx
);
6887 ssh
->crcda_ctx
= NULL
;
6895 * Reconfigure the SSH backend.
6897 * Currently, this function does nothing very useful. In future,
6898 * however, we could do some handy things with it. For example, we
6899 * could make the port forwarding configurer active in the Change
6900 * Settings box, and this routine could close down existing
6901 * forwardings and open up new ones in response to changes.
6903 static void ssh_reconfig(void *handle
, Config
*cfg
)
6905 Ssh ssh
= (Ssh
) handle
;
6906 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
6910 * Called to send data down the Telnet connection.
6912 static int ssh_send(void *handle
, char *buf
, int len
)
6914 Ssh ssh
= (Ssh
) handle
;
6916 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
6919 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
6921 return ssh_sendbuffer(ssh
);
6925 * Called to query the current amount of buffered stdin data.
6927 static int ssh_sendbuffer(void *handle
)
6929 Ssh ssh
= (Ssh
) handle
;
6932 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
6936 * If the SSH socket itself has backed up, add the total backup
6937 * size on that to any individual buffer on the stdin channel.
6940 if (ssh
->throttled_all
)
6941 override_value
= ssh
->overall_bufsize
;
6943 if (ssh
->version
== 1) {
6944 return override_value
;
6945 } else if (ssh
->version
== 2) {
6946 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
6947 return override_value
;
6949 return (override_value
+
6950 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
6957 * Called to set the size of the window from SSH's POV.
6959 static void ssh_size(void *handle
, int width
, int height
)
6961 Ssh ssh
= (Ssh
) handle
;
6962 struct Packet
*pktout
;
6964 ssh
->term_width
= width
;
6965 ssh
->term_height
= height
;
6967 switch (ssh
->state
) {
6968 case SSH_STATE_BEFORE_SIZE
:
6969 case SSH_STATE_PREPACKET
:
6970 case SSH_STATE_CLOSED
:
6971 break; /* do nothing */
6972 case SSH_STATE_INTERMED
:
6973 ssh
->size_needed
= TRUE
; /* buffer for later */
6975 case SSH_STATE_SESSION
:
6976 if (!ssh
->cfg
.nopty
) {
6977 if (ssh
->version
== 1) {
6978 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
6979 PKT_INT
, ssh
->term_height
,
6980 PKT_INT
, ssh
->term_width
,
6981 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
6982 } else if (ssh
->mainchan
) {
6983 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6984 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
6985 ssh2_pkt_addstring(pktout
, "window-change");
6986 ssh2_pkt_addbool(pktout
, 0);
6987 ssh2_pkt_adduint32(pktout
, ssh
->term_width
);
6988 ssh2_pkt_adduint32(pktout
, ssh
->term_height
);
6989 ssh2_pkt_adduint32(pktout
, 0);
6990 ssh2_pkt_adduint32(pktout
, 0);
6991 ssh2_pkt_send(ssh
, pktout
);
6999 * Return a list of the special codes that make sense in this
7002 static const struct telnet_special
*ssh_get_specials(void *handle
)
7004 static const struct telnet_special ignore_special
[] = {
7005 {"IGNORE message", TS_NOP
},
7007 static const struct telnet_special ssh2_session_specials
[] = {
7010 /* These are the signal names defined by draft-ietf-secsh-connect-19.
7011 * They include all the ISO C signals, but are a subset of the POSIX
7012 * required signals. */
7013 {"SIGINT (Interrupt)", TS_SIGINT
},
7014 {"SIGTERM (Terminate)", TS_SIGTERM
},
7015 {"SIGKILL (Kill)", TS_SIGKILL
},
7016 {"SIGQUIT (Quit)", TS_SIGQUIT
},
7017 {"SIGHUP (Hangup)", TS_SIGHUP
},
7018 {"More signals", TS_SUBMENU
},
7019 {"SIGABRT", TS_SIGABRT
}, {"SIGALRM", TS_SIGALRM
},
7020 {"SIGFPE", TS_SIGFPE
}, {"SIGILL", TS_SIGILL
},
7021 {"SIGPIPE", TS_SIGPIPE
}, {"SIGSEGV", TS_SIGSEGV
},
7022 {"SIGUSR1", TS_SIGUSR1
}, {"SIGUSR2", TS_SIGUSR2
},
7025 static const struct telnet_special specials_end
[] = {
7028 static struct telnet_special ssh_specials
[lenof(ignore_special
) +
7029 lenof(ssh2_session_specials
) +
7030 lenof(specials_end
)];
7031 Ssh ssh
= (Ssh
) handle
;
7033 #define ADD_SPECIALS(name) \
7035 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7036 memcpy(&ssh_specials[i], name, sizeof name); \
7040 if (ssh
->version
== 1) {
7041 /* Don't bother offering IGNORE if we've decided the remote
7042 * won't cope with it, since we wouldn't bother sending it if
7044 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7045 ADD_SPECIALS(ignore_special
);
7046 } else if (ssh
->version
== 2) {
7047 /* XXX add rekey, when implemented */
7048 ADD_SPECIALS(ignore_special
);
7050 ADD_SPECIALS(ssh2_session_specials
);
7051 } /* else we're not ready yet */
7054 ADD_SPECIALS(specials_end
);
7055 return ssh_specials
;
7063 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7064 * can send an EOF and collect resulting output (e.g. `plink
7067 static void ssh_special(void *handle
, Telnet_Special code
)
7069 Ssh ssh
= (Ssh
) handle
;
7070 struct Packet
*pktout
;
7072 if (code
== TS_EOF
) {
7073 if (ssh
->state
!= SSH_STATE_SESSION
) {
7075 * Buffer the EOF in case we are pre-SESSION, so we can
7076 * send it as soon as we reach SESSION.
7079 ssh
->eof_needed
= TRUE
;
7082 if (ssh
->version
== 1) {
7083 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
7084 } else if (ssh
->mainchan
) {
7085 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
7086 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7087 ssh2_pkt_send(ssh
, pktout
);
7089 logevent("Sent EOF message");
7090 } else if (code
== TS_PING
|| code
== TS_NOP
) {
7091 if (ssh
->state
== SSH_STATE_CLOSED
7092 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7093 if (ssh
->version
== 1) {
7094 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7095 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
7097 pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
7098 ssh2_pkt_addstring_start(pktout
);
7099 ssh2_pkt_send(ssh
, pktout
);
7101 } else if (code
== TS_BRK
) {
7102 if (ssh
->state
== SSH_STATE_CLOSED
7103 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7104 if (ssh
->version
== 1) {
7105 logevent("Unable to send BREAK signal in SSH1");
7106 } else if (ssh
->mainchan
) {
7107 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7108 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7109 ssh2_pkt_addstring(pktout
, "break");
7110 ssh2_pkt_addbool(pktout
, 0);
7111 ssh2_pkt_adduint32(pktout
, 0); /* default break length */
7112 ssh2_pkt_send(ssh
, pktout
);
7115 /* Is is a POSIX signal? */
7116 char *signame
= NULL
;
7117 if (code
== TS_SIGABRT
) signame
= "ABRT";
7118 if (code
== TS_SIGALRM
) signame
= "ALRM";
7119 if (code
== TS_SIGFPE
) signame
= "FPE";
7120 if (code
== TS_SIGHUP
) signame
= "HUP";
7121 if (code
== TS_SIGILL
) signame
= "ILL";
7122 if (code
== TS_SIGINT
) signame
= "INT";
7123 if (code
== TS_SIGKILL
) signame
= "KILL";
7124 if (code
== TS_SIGPIPE
) signame
= "PIPE";
7125 if (code
== TS_SIGQUIT
) signame
= "QUIT";
7126 if (code
== TS_SIGSEGV
) signame
= "SEGV";
7127 if (code
== TS_SIGTERM
) signame
= "TERM";
7128 if (code
== TS_SIGUSR1
) signame
= "USR1";
7129 if (code
== TS_SIGUSR2
) signame
= "USR2";
7130 /* The SSH-2 protocol does in principle support arbitrary named
7131 * signals, including signame@domain, but we don't support those. */
7133 /* It's a signal. */
7134 if (ssh
->version
== 2 && ssh
->mainchan
) {
7135 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7136 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7137 ssh2_pkt_addstring(pktout
, "signal");
7138 ssh2_pkt_addbool(pktout
, 0);
7139 ssh2_pkt_addstring(pktout
, signame
);
7140 ssh2_pkt_send(ssh
, pktout
);
7141 logeventf(ssh
, "Sent signal SIG%s", signame
);
7144 /* Never heard of it. Do nothing */
7149 void *new_sock_channel(void *handle
, Socket s
)
7151 Ssh ssh
= (Ssh
) handle
;
7152 struct ssh_channel
*c
;
7153 c
= snew(struct ssh_channel
);
7157 c
->remoteid
= -1; /* to be set when open confirmed */
7158 c
->localid
= alloc_channel_id(ssh
);
7160 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
7162 bufchain_init(&c
->v
.v2
.outbuffer
);
7163 add234(ssh
->channels
, c
);
7169 * This is called when stdout/stderr (the entity to which
7170 * from_backend sends data) manages to clear some backlog.
7172 static void ssh_unthrottle(void *handle
, int bufsize
)
7174 Ssh ssh
= (Ssh
) handle
;
7175 if (ssh
->version
== 1) {
7176 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
7177 ssh
->v1_stdout_throttling
= 0;
7178 ssh1_throttle(ssh
, -1);
7181 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
7182 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
7186 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
7188 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
7190 struct Packet
*pktout
;
7192 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
7194 if (ssh
->version
== 1) {
7195 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
7196 PKT_INT
, c
->localid
,
7199 //PKT_STR, <org:orgport>,
7202 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
7203 ssh2_pkt_addstring(pktout
, "direct-tcpip");
7204 ssh2_pkt_adduint32(pktout
, c
->localid
);
7205 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7206 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);/* our window size */
7207 ssh2_pkt_adduint32(pktout
, 0x4000UL
); /* our max pkt size */
7208 ssh2_pkt_addstring(pktout
, hostname
);
7209 ssh2_pkt_adduint32(pktout
, port
);
7211 * We make up values for the originator data; partly it's
7212 * too much hassle to keep track, and partly I'm not
7213 * convinced the server should be told details like that
7214 * about my local network configuration.
7216 ssh2_pkt_addstring(pktout
, "client-side-connection");
7217 ssh2_pkt_adduint32(pktout
, 0);
7218 ssh2_pkt_send(ssh
, pktout
);
7222 static Socket
ssh_socket(void *handle
)
7224 Ssh ssh
= (Ssh
) handle
;
7228 static int ssh_sendok(void *handle
)
7230 Ssh ssh
= (Ssh
) handle
;
7231 return ssh
->send_ok
;
7234 static int ssh_ldisc(void *handle
, int option
)
7236 Ssh ssh
= (Ssh
) handle
;
7237 if (option
== LD_ECHO
)
7238 return ssh
->echoing
;
7239 if (option
== LD_EDIT
)
7240 return ssh
->editing
;
7244 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
7246 Ssh ssh
= (Ssh
) handle
;
7250 static void ssh_provide_logctx(void *handle
, void *logctx
)
7252 Ssh ssh
= (Ssh
) handle
;
7253 ssh
->logctx
= logctx
;
7256 static int ssh_return_exitcode(void *handle
)
7258 Ssh ssh
= (Ssh
) handle
;
7262 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
7266 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
7267 * that fails. This variable is the means by which scp.c can reach
7268 * into the SSH code and find out which one it got.
7270 extern int ssh_fallback_cmd(void *handle
)
7272 Ssh ssh
= (Ssh
) handle
;
7273 return ssh
->fallback_cmd
;
7276 Backend ssh_backend
= {
7286 ssh_return_exitcode
,