17 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
18 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
19 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
20 #define SSH1_CMSG_USER 4 /* 0x4 */
21 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
22 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
23 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
24 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
25 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
26 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
27 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
28 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
29 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
30 #define SSH1_SMSG_FAILURE 15 /* 0xf */
31 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
32 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
33 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
34 #define SSH1_CMSG_EOF 19 /* 0x13 */
35 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
36 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
37 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
38 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
39 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
40 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
41 #define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
42 #define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
43 #define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
44 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
45 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
46 #define SSH1_MSG_IGNORE 32 /* 0x20 */
47 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
48 #define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
49 #define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
50 #define SSH1_MSG_DEBUG 36 /* 0x24 */
51 #define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
52 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
53 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
54 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
55 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
56 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
57 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
59 #define SSH1_AUTH_TIS 5 /* 0x5 */
60 #define SSH1_AUTH_CCARD 16 /* 0x10 */
62 #define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
63 /* Mask for protoflags we will echo back to server if seen */
64 #define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
66 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
67 #define SSH2_MSG_IGNORE 2 /* 0x2 */
68 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
69 #define SSH2_MSG_DEBUG 4 /* 0x4 */
70 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
71 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
72 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
73 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
74 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
75 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
76 #define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
77 #define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
78 #define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
79 #define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
80 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
81 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
82 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
83 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
84 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
85 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
86 #define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
87 #define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
88 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
89 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
90 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
91 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
92 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
93 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
94 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
95 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
96 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
97 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
98 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
99 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
100 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
101 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
104 * Packet type contexts, so that ssh2_pkt_type can correctly decode
105 * the ambiguous type numbers back into the correct type strings.
107 #define SSH2_PKTCTX_DHGROUP 0x0001
108 #define SSH2_PKTCTX_DHGEX 0x0002
109 #define SSH2_PKTCTX_PUBLICKEY 0x0010
110 #define SSH2_PKTCTX_PASSWORD 0x0020
111 #define SSH2_PKTCTX_KBDINTER 0x0040
112 #define SSH2_PKTCTX_AUTH_MASK 0x00F0
114 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
115 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
116 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
117 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
118 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
119 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
120 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
121 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
122 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
123 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
124 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
125 #define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
126 #define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
127 #define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
128 #define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
130 static const char *const ssh2_disconnect_reasons
[] = {
132 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
133 "SSH_DISCONNECT_PROTOCOL_ERROR",
134 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
135 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
136 "SSH_DISCONNECT_MAC_ERROR",
137 "SSH_DISCONNECT_COMPRESSION_ERROR",
138 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
139 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
140 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
141 "SSH_DISCONNECT_CONNECTION_LOST",
142 "SSH_DISCONNECT_BY_APPLICATION",
143 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
144 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
145 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
146 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
149 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
150 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
151 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
152 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
154 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
157 * Various remote-bug flags.
159 #define BUG_CHOKES_ON_SSH1_IGNORE 1
160 #define BUG_SSH2_HMAC 2
161 #define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
162 #define BUG_CHOKES_ON_RSA 8
163 #define BUG_SSH2_RSA_PADDING 16
164 #define BUG_SSH2_DERIVEKEY 32
165 /* 64 was BUG_SSH2_DH_GEX, now spare */
166 #define BUG_SSH2_PK_SESSIONID 128
168 #define translate(x) if (type == x) return #x
169 #define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
170 static char *ssh1_pkt_type(int type
)
172 translate(SSH1_MSG_DISCONNECT
);
173 translate(SSH1_SMSG_PUBLIC_KEY
);
174 translate(SSH1_CMSG_SESSION_KEY
);
175 translate(SSH1_CMSG_USER
);
176 translate(SSH1_CMSG_AUTH_RSA
);
177 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE
);
178 translate(SSH1_CMSG_AUTH_RSA_RESPONSE
);
179 translate(SSH1_CMSG_AUTH_PASSWORD
);
180 translate(SSH1_CMSG_REQUEST_PTY
);
181 translate(SSH1_CMSG_WINDOW_SIZE
);
182 translate(SSH1_CMSG_EXEC_SHELL
);
183 translate(SSH1_CMSG_EXEC_CMD
);
184 translate(SSH1_SMSG_SUCCESS
);
185 translate(SSH1_SMSG_FAILURE
);
186 translate(SSH1_CMSG_STDIN_DATA
);
187 translate(SSH1_SMSG_STDOUT_DATA
);
188 translate(SSH1_SMSG_STDERR_DATA
);
189 translate(SSH1_CMSG_EOF
);
190 translate(SSH1_SMSG_EXIT_STATUS
);
191 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
);
192 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE
);
193 translate(SSH1_MSG_CHANNEL_DATA
);
194 translate(SSH1_MSG_CHANNEL_CLOSE
);
195 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
);
196 translate(SSH1_SMSG_X11_OPEN
);
197 translate(SSH1_CMSG_PORT_FORWARD_REQUEST
);
198 translate(SSH1_MSG_PORT_OPEN
);
199 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING
);
200 translate(SSH1_SMSG_AGENT_OPEN
);
201 translate(SSH1_MSG_IGNORE
);
202 translate(SSH1_CMSG_EXIT_CONFIRMATION
);
203 translate(SSH1_CMSG_X11_REQUEST_FORWARDING
);
204 translate(SSH1_CMSG_AUTH_RHOSTS_RSA
);
205 translate(SSH1_MSG_DEBUG
);
206 translate(SSH1_CMSG_REQUEST_COMPRESSION
);
207 translate(SSH1_CMSG_AUTH_TIS
);
208 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE
);
209 translate(SSH1_CMSG_AUTH_TIS_RESPONSE
);
210 translate(SSH1_CMSG_AUTH_CCARD
);
211 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE
);
212 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE
);
215 static char *ssh2_pkt_type(int pkt_ctx
, int type
)
217 translate(SSH2_MSG_DISCONNECT
);
218 translate(SSH2_MSG_IGNORE
);
219 translate(SSH2_MSG_UNIMPLEMENTED
);
220 translate(SSH2_MSG_DEBUG
);
221 translate(SSH2_MSG_SERVICE_REQUEST
);
222 translate(SSH2_MSG_SERVICE_ACCEPT
);
223 translate(SSH2_MSG_KEXINIT
);
224 translate(SSH2_MSG_NEWKEYS
);
225 translatec(SSH2_MSG_KEXDH_INIT
, SSH2_PKTCTX_DHGROUP
);
226 translatec(SSH2_MSG_KEXDH_REPLY
, SSH2_PKTCTX_DHGROUP
);
227 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST
, SSH2_PKTCTX_DHGEX
);
228 translatec(SSH2_MSG_KEX_DH_GEX_GROUP
, SSH2_PKTCTX_DHGEX
);
229 translatec(SSH2_MSG_KEX_DH_GEX_INIT
, SSH2_PKTCTX_DHGEX
);
230 translatec(SSH2_MSG_KEX_DH_GEX_REPLY
, SSH2_PKTCTX_DHGEX
);
231 translate(SSH2_MSG_USERAUTH_REQUEST
);
232 translate(SSH2_MSG_USERAUTH_FAILURE
);
233 translate(SSH2_MSG_USERAUTH_SUCCESS
);
234 translate(SSH2_MSG_USERAUTH_BANNER
);
235 translatec(SSH2_MSG_USERAUTH_PK_OK
, SSH2_PKTCTX_PUBLICKEY
);
236 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
, SSH2_PKTCTX_PASSWORD
);
237 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST
, SSH2_PKTCTX_KBDINTER
);
238 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE
, SSH2_PKTCTX_KBDINTER
);
239 translate(SSH2_MSG_GLOBAL_REQUEST
);
240 translate(SSH2_MSG_REQUEST_SUCCESS
);
241 translate(SSH2_MSG_REQUEST_FAILURE
);
242 translate(SSH2_MSG_CHANNEL_OPEN
);
243 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
244 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
245 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
246 translate(SSH2_MSG_CHANNEL_DATA
);
247 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA
);
248 translate(SSH2_MSG_CHANNEL_EOF
);
249 translate(SSH2_MSG_CHANNEL_CLOSE
);
250 translate(SSH2_MSG_CHANNEL_REQUEST
);
251 translate(SSH2_MSG_CHANNEL_SUCCESS
);
252 translate(SSH2_MSG_CHANNEL_FAILURE
);
258 #define GET_32BIT(cp) \
259 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
260 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
261 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
262 ((unsigned long)(unsigned char)(cp)[3]))
264 #define PUT_32BIT(cp, value) { \
265 (cp)[0] = (unsigned char)((value) >> 24); \
266 (cp)[1] = (unsigned char)((value) >> 16); \
267 (cp)[2] = (unsigned char)((value) >> 8); \
268 (cp)[3] = (unsigned char)(value); }
270 /* Enumeration values for fields in SSH-1 packets */
272 PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
,
273 /* These values are for communicating relevant semantics of
274 * fields to the packet logging code. */
275 PKTT_OTHER
, PKTT_PASSWORD
, PKTT_DATA
279 * Coroutine mechanics for the sillier bits of the code. If these
280 * macros look impenetrable to you, you might find it helpful to
283 * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
285 * which explains the theory behind these macros.
287 * In particular, if you are getting `case expression not constant'
288 * errors when building with MS Visual Studio, this is because MS's
289 * Edit and Continue debugging feature causes their compiler to
290 * violate ANSI C. To disable Edit and Continue debugging:
292 * - right-click ssh.c in the FileView
294 * - select the C/C++ tab and the General category
295 * - under `Debug info:', select anything _other_ than `Program
296 * Database for Edit and Continue'.
298 #define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
301 if (!ssh->t) ssh->t = snew(struct t); \
303 #define crFinish(z) } *crLine = 0; return (z); }
304 #define crFinishV } *crLine = 0; return; }
305 #define crReturn(z) \
307 *crLine =__LINE__; return (z); case __LINE__:;\
311 *crLine=__LINE__; return; case __LINE__:;\
313 #define crStop(z) do{ *crLine = 0; return (z); }while(0)
314 #define crStopV do{ *crLine = 0; return; }while(0)
315 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
316 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
318 typedef struct ssh_tag
*Ssh
;
321 static struct Packet
*ssh2_pkt_init(int pkt_type
);
322 static void ssh2_pkt_addbool(struct Packet
*, unsigned char value
);
323 static void ssh2_pkt_adduint32(struct Packet
*, unsigned long value
);
324 static void ssh2_pkt_addstring_start(struct Packet
*);
325 static void ssh2_pkt_addstring_str(struct Packet
*, char *data
);
326 static void ssh2_pkt_addstring_data(struct Packet
*, char *data
, int len
);
327 static void ssh2_pkt_addstring(struct Packet
*, char *data
);
328 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
);
329 static void ssh2_pkt_addmp(struct Packet
*, Bignum b
);
330 static int ssh2_pkt_construct(Ssh
, struct Packet
*);
331 static void ssh2_pkt_send(Ssh
, struct Packet
*);
332 static void ssh2_pkt_send_noqueue(Ssh
, struct Packet
*);
333 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
334 struct Packet
*pktin
);
335 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
336 struct Packet
*pktin
);
339 * Buffer management constants. There are several of these for
340 * various different purposes:
342 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
343 * on a local data stream before we throttle the whole SSH
344 * connection (in SSH1 only). Throttling the whole connection is
345 * pretty drastic so we set this high in the hope it won't
348 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
349 * on the SSH connection itself before we defensively throttle
350 * _all_ local data streams. This is pretty drastic too (though
351 * thankfully unlikely in SSH2 since the window mechanism should
352 * ensure that the server never has any need to throttle its end
353 * of the connection), so we set this high as well.
355 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
359 #define SSH1_BUFFER_LIMIT 32768
360 #define SSH_MAX_BACKLOG 32768
361 #define OUR_V2_WINSIZE 16384
363 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
365 static void *nullmac_make_context(void)
369 static void nullmac_free_context(void *handle
)
372 static void nullmac_key(void *handle
, unsigned char *key
)
375 static void nullmac_generate(void *handle
, unsigned char *blk
, int len
,
379 static int nullmac_verify(void *handle
, unsigned char *blk
, int len
,
384 const static struct ssh_mac ssh_mac_none
= {
385 nullmac_make_context
, nullmac_free_context
, nullmac_key
,
386 nullmac_generate
, nullmac_verify
, "none", 0
388 const static struct ssh_mac
*macs
[] = {
389 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
391 const static struct ssh_mac
*buggymacs
[] = {
392 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
395 static void *ssh_comp_none_init(void)
399 static void ssh_comp_none_cleanup(void *handle
)
402 static int ssh_comp_none_block(void *handle
, unsigned char *block
, int len
,
403 unsigned char **outblock
, int *outlen
)
407 static int ssh_comp_none_disable(void *handle
)
411 const static struct ssh_compress ssh_comp_none
= {
413 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
414 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
415 ssh_comp_none_disable
, NULL
417 extern const struct ssh_compress ssh_zlib
;
418 const static struct ssh_compress
*compressions
[] = {
419 &ssh_zlib
, &ssh_comp_none
422 enum { /* channel types */
427 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
431 * 2-3-4 tree storing channels.
434 Ssh ssh
; /* pointer back to main context */
435 unsigned remoteid
, localid
;
438 * In SSH1, this value contains four bits:
440 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
441 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
442 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
443 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
445 * A channel is completely finished with when all four bits are set.
449 struct ssh1_data_channel
{
452 struct ssh2_data_channel
{
454 unsigned remwindow
, remmaxpkt
;
459 struct ssh_agent_channel
{
460 unsigned char *message
;
461 unsigned char msglen
[4];
462 unsigned lensofar
, totallen
;
464 struct ssh_x11_channel
{
467 struct ssh_pfd_channel
{
474 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
475 * 2 use this structure in different ways, reflecting SSH 2's
476 * altogether saner approach to port forwarding.
478 * In SSH 1, you arrange a remote forwarding by sending the server
479 * the remote port number, and the local destination host:port.
480 * When a connection comes in, the server sends you back that
481 * host:port pair, and you connect to it. This is a ready-made
482 * security hole if you're not on the ball: a malicious server
483 * could send you back _any_ host:port pair, so if you trustingly
484 * connect to the address it gives you then you've just opened the
485 * entire inside of your corporate network just by connecting
486 * through it to a dodgy SSH server. Hence, we must store a list of
487 * host:port pairs we _are_ trying to forward to, and reject a
488 * connection request from the server if it's not in the list.
490 * In SSH 2, each side of the connection minds its own business and
491 * doesn't send unnecessary information to the other. You arrange a
492 * remote forwarding by sending the server just the remote port
493 * number. When a connection comes in, the server tells you which
494 * of its ports was connected to; and _you_ have to remember what
495 * local host:port pair went with that port number.
497 * Hence, in SSH 1 this structure is indexed by destination
498 * host:port pair, whereas in SSH 2 it is indexed by source port.
500 struct ssh_portfwd
; /* forward declaration */
502 struct ssh_rportfwd
{
503 unsigned sport
, dport
;
506 struct ssh_portfwd
*pfrec
;
508 #define free_rportfwd(pf) ( \
509 ((pf) ? (sfree((pf)->sportdesc)) : (void)0 ), sfree(pf) )
512 * Separately to the rportfwd tree (which is for looking up port
513 * open requests from the server), a tree of _these_ structures is
514 * used to keep track of all the currently open port forwardings,
515 * so that we can reconfigure in mid-session if the user requests
521 unsigned sport
, dport
;
523 struct ssh_rportfwd
*remote
;
526 #define free_portfwd(pf) ( \
527 ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr)) : (void)0 ), sfree(pf) )
532 unsigned long sequence
;
537 long encrypted_len
; /* for SSH2 total-size counting */
540 * State associated with packet logging
544 struct logblank_t
*blanks
;
547 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
548 struct Packet
*pktin
);
549 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
550 struct Packet
*pktin
);
551 static void ssh1_protocol_setup(Ssh ssh
);
552 static void ssh2_protocol_setup(Ssh ssh
);
553 static void ssh_size(void *handle
, int width
, int height
);
554 static void ssh_special(void *handle
, Telnet_Special
);
555 static int ssh2_try_send(struct ssh_channel
*c
);
556 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
557 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
558 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
559 static int ssh_sendbuffer(void *handle
);
560 static void ssh_do_close(Ssh ssh
);
561 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
);
562 static int ssh2_pkt_getbool(struct Packet
*pkt
);
563 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
);
564 static void ssh2_timer(void *ctx
, long now
);
565 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
,
566 struct Packet
*pktin
);
568 struct rdpkt1_state_tag
{
569 long len
, pad
, biglen
, to_read
;
570 unsigned long realcrc
, gotcrc
;
574 struct Packet
*pktin
;
577 struct rdpkt2_state_tag
{
578 long len
, pad
, payload
, packetlen
, maclen
;
581 unsigned long incoming_sequence
;
582 struct Packet
*pktin
;
585 typedef void (*handler_fn_t
)(Ssh ssh
, struct Packet
*pktin
);
586 typedef void (*chandler_fn_t
)(Ssh ssh
, struct Packet
*pktin
, void *ctx
);
588 struct queued_handler
;
589 struct queued_handler
{
591 chandler_fn_t handler
;
593 struct queued_handler
*next
;
597 const struct plug_function_table
*fn
;
598 /* the above field _must_ be first in the structure */
600 SHA_State exhash
, exhashbase
;
607 unsigned char session_key
[32];
609 int v1_remote_protoflags
;
610 int v1_local_protoflags
;
611 int agentfwd_enabled
;
614 const struct ssh_cipher
*cipher
;
617 const struct ssh2_cipher
*cscipher
, *sccipher
;
618 void *cs_cipher_ctx
, *sc_cipher_ctx
;
619 const struct ssh_mac
*csmac
, *scmac
;
620 void *cs_mac_ctx
, *sc_mac_ctx
;
621 const struct ssh_compress
*cscomp
, *sccomp
;
622 void *cs_comp_ctx
, *sc_comp_ctx
;
623 const struct ssh_kex
*kex
;
624 const struct ssh_signkey
*hostkey
;
625 unsigned char v2_session_id
[20];
631 int echoing
, editing
;
635 int ospeed
, ispeed
; /* temporaries */
636 int term_width
, term_height
;
638 tree234
*channels
; /* indexed by local id */
639 struct ssh_channel
*mainchan
; /* primary session channel */
642 tree234
*rportfwds
, *portfwds
;
646 SSH_STATE_BEFORE_SIZE
,
652 int size_needed
, eof_needed
;
654 struct Packet
**queue
;
655 int queuelen
, queuesize
;
657 unsigned char *deferred_send_data
;
658 int deferred_len
, deferred_size
;
661 * Gross hack: pscp will try to start SFTP but fall back to
662 * scp1 if that fails. This variable is the means by which
663 * scp.c can reach into the SSH code and find out which one it
669 * Used for username and password input.
671 char *userpass_input_buffer
;
672 int userpass_input_buflen
;
673 int userpass_input_bufpos
;
674 int userpass_input_echo
;
681 int v1_throttle_count
;
684 int v1_stdout_throttling
;
685 int v2_outgoing_sequence
;
687 int ssh1_rdpkt_crstate
;
688 int ssh2_rdpkt_crstate
;
689 int do_ssh_init_crstate
;
690 int ssh_gotdata_crstate
;
691 int do_ssh1_login_crstate
;
692 int do_ssh1_connection_crstate
;
693 int do_ssh2_transport_crstate
;
694 int do_ssh2_authconn_crstate
;
696 void *do_ssh_init_state
;
697 void *do_ssh1_login_state
;
698 void *do_ssh2_transport_state
;
699 void *do_ssh2_authconn_state
;
701 struct rdpkt1_state_tag rdpkt1_state
;
702 struct rdpkt2_state_tag rdpkt2_state
;
704 /* ssh1 and ssh2 use this for different things, but both use it */
705 int protocol_initial_phase_done
;
707 void (*protocol
) (Ssh ssh
, unsigned char *in
, int inlen
,
709 struct Packet
*(*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
712 * We maintain a full _copy_ of a Config structure here, not
713 * merely a pointer to it. That way, when we're passed a new
714 * one for reconfiguration, we can check the differences and
715 * potentially reconfigure port forwardings etc in mid-session.
720 * Used to transfer data back from async agent callbacks.
722 void *agent_response
;
723 int agent_response_len
;
726 * Dispatch table for packet types that we may have to deal
729 handler_fn_t packet_dispatch
[256];
732 * Queues of one-off handler functions for success/failure
733 * indications from a request.
735 struct queued_handler
*qhead
, *qtail
;
738 * This module deals with sending keepalives.
743 * Track incoming and outgoing data sizes and time, for
746 unsigned long incoming_data_size
, outgoing_data_size
, deferred_data_size
;
747 unsigned long max_data_size
;
749 long next_rekey
, last_rekey
;
752 #define logevent(s) logevent(ssh->frontend, s)
754 /* logevent, only printf-formatted. */
755 static void logeventf(Ssh ssh
, const char *fmt
, ...)
761 buf
= dupvprintf(fmt
, ap
);
767 #define bombout(msg) \
769 char *text = dupprintf msg; \
772 connection_fatal(ssh->frontend, "%s", text); \
776 /* Functions to leave bits out of the SSH packet log file. */
778 static void dont_log_password(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
780 if (ssh
->cfg
.logomitpass
)
781 pkt
->logmode
= blanktype
;
784 static void dont_log_data(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
786 if (ssh
->cfg
.logomitdata
)
787 pkt
->logmode
= blanktype
;
790 static void end_log_omission(Ssh ssh
, struct Packet
*pkt
)
792 pkt
->logmode
= PKTLOG_EMIT
;
795 static int ssh_channelcmp(void *av
, void *bv
)
797 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
798 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
799 if (a
->localid
< b
->localid
)
801 if (a
->localid
> b
->localid
)
805 static int ssh_channelfind(void *av
, void *bv
)
807 unsigned *a
= (unsigned *) av
;
808 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
816 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
818 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
819 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
821 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
822 return i
< 0 ?
-1 : +1;
823 if (a
->dport
> b
->dport
)
825 if (a
->dport
< b
->dport
)
830 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
832 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
833 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
835 if (a
->sport
> b
->sport
)
837 if (a
->sport
< b
->sport
)
843 * Special form of strcmp which can cope with NULL inputs. NULL is
844 * defined to sort before even the empty string.
846 static int nullstrcmp(const char *a
, const char *b
)
848 if (a
== NULL
&& b
== NULL
)
857 static int ssh_portcmp(void *av
, void *bv
)
859 struct ssh_portfwd
*a
= (struct ssh_portfwd
*) av
;
860 struct ssh_portfwd
*b
= (struct ssh_portfwd
*) bv
;
862 if (a
->type
> b
->type
)
864 if (a
->type
< b
->type
)
866 if ( (i
= nullstrcmp(a
->saddr
, b
->saddr
)) != 0)
867 return i
< 0 ?
-1 : +1;
868 if (a
->sport
> b
->sport
)
870 if (a
->sport
< b
->sport
)
872 if (a
->type
!= 'D') {
873 if ( (i
= nullstrcmp(a
->daddr
, b
->daddr
)) != 0)
874 return i
< 0 ?
-1 : +1;
875 if (a
->dport
> b
->dport
)
877 if (a
->dport
< b
->dport
)
883 static int alloc_channel_id(Ssh ssh
)
885 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
886 unsigned low
, high
, mid
;
888 struct ssh_channel
*c
;
891 * First-fit allocation of channel numbers: always pick the
892 * lowest unused one. To do this, binary-search using the
893 * counted B-tree to find the largest channel ID which is in a
894 * contiguous sequence from the beginning. (Precisely
895 * everything in that sequence must have ID equal to its tree
896 * index plus CHANNEL_NUMBER_OFFSET.)
898 tsize
= count234(ssh
->channels
);
902 while (high
- low
> 1) {
903 mid
= (high
+ low
) / 2;
904 c
= index234(ssh
->channels
, mid
);
905 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
906 low
= mid
; /* this one is fine */
908 high
= mid
; /* this one is past it */
911 * Now low points to either -1, or the tree index of the
912 * largest ID in the initial sequence.
915 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
916 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
918 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
921 static void c_write(Ssh ssh
, const char *buf
, int len
)
923 if ((flags
& FLAG_STDERR
)) {
925 for (i
= 0; i
< len
; i
++)
927 fputc(buf
[i
], stderr
);
930 from_backend(ssh
->frontend
, 1, buf
, len
);
933 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
936 for (i
= 0; i
< len
; i
++) {
938 c_write(ssh
, "\r\n", 2);
939 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
940 c_write(ssh
, buf
+ i
, 1);
944 static void c_write_str(Ssh ssh
, const char *buf
)
946 c_write(ssh
, buf
, strlen(buf
));
949 static void ssh_free_packet(struct Packet
*pkt
)
954 static struct Packet
*ssh_new_packet(void)
956 struct Packet
*pkt
= snew(struct Packet
);
960 pkt
->logmode
= PKTLOG_EMIT
;
968 * Collect incoming data in the incoming packet buffer.
969 * Decipher and verify the packet when it is completely read.
970 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
971 * Update the *data and *datalen variables.
972 * Return a Packet structure when a packet is completed.
974 static struct Packet
*ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
976 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
978 crBegin(ssh
->ssh1_rdpkt_crstate
);
980 st
->pktin
= ssh_new_packet();
983 st
->pktin
->length
= 0;
985 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
986 while ((*datalen
) == 0)
988 st
->len
= (st
->len
<< 8) + **data
;
989 (*data
)++, (*datalen
)--;
992 st
->pad
= 8 - (st
->len
% 8);
993 st
->biglen
= st
->len
+ st
->pad
;
994 st
->pktin
->length
= st
->len
- 5;
996 if (st
->biglen
< 0) {
997 bombout(("Extremely large packet length from server suggests"
998 " data stream corruption"));
999 ssh_free_packet(st
->pktin
);
1003 st
->pktin
->maxlen
= st
->biglen
;
1004 st
->pktin
->data
= snewn(st
->biglen
+ APIEXTRA
, unsigned char);
1006 st
->to_read
= st
->biglen
;
1007 st
->p
= st
->pktin
->data
;
1008 while (st
->to_read
> 0) {
1009 st
->chunk
= st
->to_read
;
1010 while ((*datalen
) == 0)
1012 if (st
->chunk
> (*datalen
))
1013 st
->chunk
= (*datalen
);
1014 memcpy(st
->p
, *data
, st
->chunk
);
1016 *datalen
-= st
->chunk
;
1018 st
->to_read
-= st
->chunk
;
1021 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, st
->pktin
->data
,
1022 st
->biglen
, NULL
)) {
1023 bombout(("Network attack (CRC compensation) detected!"));
1024 ssh_free_packet(st
->pktin
);
1029 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, st
->pktin
->data
, st
->biglen
);
1031 st
->realcrc
= crc32_compute(st
->pktin
->data
, st
->biglen
- 4);
1032 st
->gotcrc
= GET_32BIT(st
->pktin
->data
+ st
->biglen
- 4);
1033 if (st
->gotcrc
!= st
->realcrc
) {
1034 bombout(("Incorrect CRC received on packet"));
1035 ssh_free_packet(st
->pktin
);
1039 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1040 st
->pktin
->savedpos
= 0;
1042 if (ssh
->v1_compressing
) {
1043 unsigned char *decompblk
;
1045 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
1046 st
->pktin
->body
- 1, st
->pktin
->length
+ 1,
1047 &decompblk
, &decomplen
)) {
1048 bombout(("Zlib decompression encountered invalid data"));
1049 ssh_free_packet(st
->pktin
);
1053 if (st
->pktin
->maxlen
< st
->pad
+ decomplen
) {
1054 st
->pktin
->maxlen
= st
->pad
+ decomplen
;
1055 st
->pktin
->data
= sresize(st
->pktin
->data
,
1056 st
->pktin
->maxlen
+ APIEXTRA
,
1058 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1061 memcpy(st
->pktin
->body
- 1, decompblk
, decomplen
);
1063 st
->pktin
->length
= decomplen
- 1;
1066 st
->pktin
->type
= st
->pktin
->body
[-1];
1069 * Log incoming packet, possibly omitting sensitive fields.
1073 struct logblank_t blank
;
1074 if (ssh
->cfg
.logomitdata
) {
1075 int do_blank
= FALSE
, blank_prefix
= 0;
1076 /* "Session data" packets - omit the data field */
1077 if ((st
->pktin
->type
== SSH1_SMSG_STDOUT_DATA
) ||
1078 (st
->pktin
->type
== SSH1_SMSG_STDERR_DATA
)) {
1079 do_blank
= TRUE
; blank_prefix
= 0;
1080 } else if (st
->pktin
->type
== SSH1_MSG_CHANNEL_DATA
) {
1081 do_blank
= TRUE
; blank_prefix
= 4;
1084 blank
.offset
= blank_prefix
;
1085 blank
.len
= st
->pktin
->length
;
1086 blank
.type
= PKTLOG_OMIT
;
1090 log_packet(ssh
->logctx
,
1091 PKT_INCOMING
, st
->pktin
->type
,
1092 ssh1_pkt_type(st
->pktin
->type
),
1093 st
->pktin
->body
, st
->pktin
->length
,
1097 crFinish(st
->pktin
);
1100 static struct Packet
*ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1102 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1104 crBegin(ssh
->ssh2_rdpkt_crstate
);
1106 st
->pktin
= ssh_new_packet();
1108 st
->pktin
->type
= 0;
1109 st
->pktin
->length
= 0;
1111 st
->cipherblk
= ssh
->sccipher
->blksize
;
1114 if (st
->cipherblk
< 8)
1117 st
->pktin
->data
= snewn(st
->cipherblk
+ APIEXTRA
, unsigned char);
1120 * Acquire and decrypt the first block of the packet. This will
1121 * contain the length and padding details.
1123 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1124 while ((*datalen
) == 0)
1126 st
->pktin
->data
[st
->i
] = *(*data
)++;
1131 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1132 st
->pktin
->data
, st
->cipherblk
);
1135 * Now get the length and padding figures.
1137 st
->len
= GET_32BIT(st
->pktin
->data
);
1138 st
->pad
= st
->pktin
->data
[4];
1141 * _Completely_ silly lengths should be stomped on before they
1142 * do us any more damage.
1144 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
1145 bombout(("Incoming packet was garbled on decryption"));
1146 ssh_free_packet(st
->pktin
);
1151 * This enables us to deduce the payload length.
1153 st
->payload
= st
->len
- st
->pad
- 1;
1155 st
->pktin
->length
= st
->payload
+ 5;
1158 * So now we can work out the total packet length.
1160 st
->packetlen
= st
->len
+ 4;
1161 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1164 * Allocate memory for the rest of the packet.
1166 st
->pktin
->maxlen
= st
->packetlen
+ st
->maclen
;
1167 st
->pktin
->data
= sresize(st
->pktin
->data
,
1168 st
->pktin
->maxlen
+ APIEXTRA
,
1172 * Read and decrypt the remainder of the packet.
1174 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1176 while ((*datalen
) == 0)
1178 st
->pktin
->data
[st
->i
] = *(*data
)++;
1181 /* Decrypt everything _except_ the MAC. */
1183 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1184 st
->pktin
->data
+ st
->cipherblk
,
1185 st
->packetlen
- st
->cipherblk
);
1187 st
->pktin
->encrypted_len
= st
->packetlen
;
1193 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, st
->pktin
->data
, st
->len
+ 4,
1194 st
->incoming_sequence
)) {
1195 bombout(("Incorrect MAC received on packet"));
1196 ssh_free_packet(st
->pktin
);
1200 st
->pktin
->sequence
= st
->incoming_sequence
++;
1203 * Decompress packet payload.
1206 unsigned char *newpayload
;
1209 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1210 st
->pktin
->data
+ 5, st
->pktin
->length
- 5,
1211 &newpayload
, &newlen
)) {
1212 if (st
->pktin
->maxlen
< newlen
+ 5) {
1213 st
->pktin
->maxlen
= newlen
+ 5;
1214 st
->pktin
->data
= sresize(st
->pktin
->data
,
1215 st
->pktin
->maxlen
+ APIEXTRA
,
1218 st
->pktin
->length
= 5 + newlen
;
1219 memcpy(st
->pktin
->data
+ 5, newpayload
, newlen
);
1224 st
->pktin
->savedpos
= 6;
1225 st
->pktin
->body
= st
->pktin
->data
;
1226 st
->pktin
->type
= st
->pktin
->data
[5];
1229 * Log incoming packet, possibly omitting sensitive fields.
1233 struct logblank_t blank
;
1234 if (ssh
->cfg
.logomitdata
) {
1235 int do_blank
= FALSE
, blank_prefix
= 0;
1236 /* "Session data" packets - omit the data field */
1237 if (st
->pktin
->type
== SSH2_MSG_CHANNEL_DATA
) {
1238 do_blank
= TRUE
; blank_prefix
= 4;
1239 } else if (st
->pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1240 do_blank
= TRUE
; blank_prefix
= 8;
1243 blank
.offset
= blank_prefix
;
1244 blank
.len
= (st
->pktin
->length
-6) - blank_prefix
;
1245 blank
.type
= PKTLOG_OMIT
;
1249 log_packet(ssh
->logctx
, PKT_INCOMING
, st
->pktin
->type
,
1250 ssh2_pkt_type(ssh
->pkt_ctx
, st
->pktin
->type
),
1251 st
->pktin
->data
+6, st
->pktin
->length
-6,
1255 crFinish(st
->pktin
);
1258 static void ssh1_pktout_size(struct Packet
*pkt
, int len
)
1262 len
+= 5; /* type and CRC */
1263 pad
= 8 - (len
% 8);
1266 pkt
->length
= len
- 5;
1267 if (pkt
->maxlen
< biglen
) {
1268 pkt
->maxlen
= biglen
;
1269 pkt
->data
= sresize(pkt
->data
, biglen
+ 4 + APIEXTRA
, unsigned char);
1271 pkt
->body
= pkt
->data
+ 4 + pad
+ 1;
1274 static struct Packet
*s_wrpkt_start(int type
, int len
)
1276 struct Packet
*pkt
= ssh_new_packet();
1277 ssh1_pktout_size(pkt
, len
);
1279 /* Initialise log omission state */
1285 static int s_wrpkt_prepare(Ssh ssh
, struct Packet
*pkt
)
1291 * XXX various versions of SC (including 8.8.4) screw up the
1292 * register allocation in this function and use the same register
1293 * (D6) for len and as a temporary, with predictable results. The
1294 * following sledgehammer prevents this.
1300 pkt
->body
[-1] = pkt
->type
;
1303 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->type
,
1304 ssh1_pkt_type(pkt
->type
),
1305 pkt
->body
, pkt
->length
,
1306 pkt
->nblanks
, pkt
->blanks
);
1307 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1310 if (ssh
->v1_compressing
) {
1311 unsigned char *compblk
;
1313 zlib_compress_block(ssh
->cs_comp_ctx
,
1314 pkt
->body
- 1, pkt
->length
+ 1,
1315 &compblk
, &complen
);
1316 ssh1_pktout_size(pkt
, complen
- 1);
1317 memcpy(pkt
->body
- 1, compblk
, complen
);
1321 len
= pkt
->length
+ 5; /* type and CRC */
1322 pad
= 8 - (len
% 8);
1325 for (i
= 0; i
< pad
; i
++)
1326 pkt
->data
[i
+ 4] = random_byte();
1327 crc
= crc32_compute(pkt
->data
+ 4, biglen
- 4);
1328 PUT_32BIT(pkt
->data
+ biglen
, crc
);
1329 PUT_32BIT(pkt
->data
, len
);
1332 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, pkt
->data
+ 4, biglen
);
1337 static void s_wrpkt(Ssh ssh
, struct Packet
*pkt
)
1340 len
= s_wrpkt_prepare(ssh
, pkt
);
1341 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1342 if (backlog
> SSH_MAX_BACKLOG
)
1343 ssh_throttle_all(ssh
, 1, backlog
);
1346 static void s_wrpkt_defer(Ssh ssh
, struct Packet
*pkt
)
1349 len
= s_wrpkt_prepare(ssh
, pkt
);
1350 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1351 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1352 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1356 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1357 ssh
->deferred_len
+= len
;
1361 * Construct a packet with the specified contents.
1363 static struct Packet
*construct_packet(Ssh ssh
, int pkttype
,
1364 va_list ap1
, va_list ap2
)
1366 unsigned char *p
, *argp
, argchar
;
1367 unsigned long argint
;
1368 int pktlen
, argtype
, arglen
;
1373 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1376 (void) va_arg(ap1
, int);
1380 (void) va_arg(ap1
, int);
1384 (void) va_arg(ap1
, unsigned char *);
1385 arglen
= va_arg(ap1
, int);
1389 argp
= va_arg(ap1
, unsigned char *);
1390 arglen
= strlen((char *)argp
);
1391 pktlen
+= 4 + arglen
;
1394 bn
= va_arg(ap1
, Bignum
);
1395 pktlen
+= ssh1_bignum_length(bn
);
1400 /* ignore this pass */
1407 pkt
= s_wrpkt_start(pkttype
, pktlen
);
1410 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1411 int offset
= p
- pkt
->body
, len
= 0;
1413 /* Actual fields in the packet */
1415 argint
= va_arg(ap2
, int);
1416 PUT_32BIT(p
, argint
);
1420 argchar
= (unsigned char) va_arg(ap2
, int);
1425 argp
= va_arg(ap2
, unsigned char *);
1426 arglen
= va_arg(ap2
, int);
1427 memcpy(p
, argp
, arglen
);
1431 argp
= va_arg(ap2
, unsigned char *);
1432 arglen
= strlen((char *)argp
);
1433 PUT_32BIT(p
, arglen
);
1434 memcpy(p
+ 4, argp
, arglen
);
1438 bn
= va_arg(ap2
, Bignum
);
1439 len
= ssh1_write_bignum(p
, bn
);
1441 /* Tokens for modifications to packet logging */
1443 dont_log_password(ssh
, pkt
, PKTLOG_BLANK
);
1446 dont_log_data(ssh
, pkt
, PKTLOG_OMIT
);
1449 end_log_omission(ssh
, pkt
);
1453 /* Deal with logfile omission, if required. */
1454 if (len
&& (pkt
->logmode
!= PKTLOG_EMIT
)) {
1456 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
,
1458 pkt
->blanks
[pkt
->nblanks
-1].offset
= offset
;
1459 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1460 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1467 static void send_packet(Ssh ssh
, int pkttype
, ...)
1471 va_start(ap1
, pkttype
);
1472 va_start(ap2
, pkttype
);
1473 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1477 ssh_free_packet(pkt
);
1480 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1484 va_start(ap1
, pkttype
);
1485 va_start(ap2
, pkttype
);
1486 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1489 s_wrpkt_defer(ssh
, pkt
);
1490 ssh_free_packet(pkt
);
1493 static int ssh_versioncmp(char *a
, char *b
)
1496 unsigned long av
, bv
;
1498 av
= strtoul(a
, &ae
, 10);
1499 bv
= strtoul(b
, &be
, 10);
1501 return (av
< bv ?
-1 : +1);
1506 av
= strtoul(ae
, &ae
, 10);
1507 bv
= strtoul(be
, &be
, 10);
1509 return (av
< bv ?
-1 : +1);
1514 * Utility routines for putting an SSH-protocol `string' and
1515 * `uint32' into a SHA state.
1518 static void sha_string(SHA_State
* s
, void *str
, int len
)
1520 unsigned char lenblk
[4];
1521 PUT_32BIT(lenblk
, len
);
1522 SHA_Bytes(s
, lenblk
, 4);
1523 SHA_Bytes(s
, str
, len
);
1526 static void sha_uint32(SHA_State
* s
, unsigned i
)
1528 unsigned char intblk
[4];
1529 PUT_32BIT(intblk
, i
);
1530 SHA_Bytes(s
, intblk
, 4);
1534 * SSH2 packet construction functions.
1536 static void ssh2_pkt_ensure(struct Packet
*pkt
, int length
)
1538 if (pkt
->maxlen
< length
) {
1539 pkt
->maxlen
= length
+ 256;
1540 pkt
->data
= sresize(pkt
->data
, pkt
->maxlen
+ APIEXTRA
, unsigned char);
1543 static void ssh2_pkt_adddata(struct Packet
*pkt
, void *data
, int len
)
1545 if (pkt
->logmode
!= PKTLOG_EMIT
) {
1547 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
, struct logblank_t
);
1548 pkt
->blanks
[pkt
->nblanks
-1].offset
= pkt
->length
- 6;
1549 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1550 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1553 ssh2_pkt_ensure(pkt
, pkt
->length
);
1554 memcpy(pkt
->data
+ pkt
->length
- len
, data
, len
);
1556 static void ssh2_pkt_addbyte(struct Packet
*pkt
, unsigned char byte
)
1558 ssh2_pkt_adddata(pkt
, &byte
, 1);
1560 static struct Packet
*ssh2_pkt_init(int pkt_type
)
1562 struct Packet
*pkt
= ssh_new_packet();
1564 ssh2_pkt_addbyte(pkt
, (unsigned char) pkt_type
);
1567 static void ssh2_pkt_addbool(struct Packet
*pkt
, unsigned char value
)
1569 ssh2_pkt_adddata(pkt
, &value
, 1);
1571 static void ssh2_pkt_adduint32(struct Packet
*pkt
, unsigned long value
)
1574 PUT_32BIT(x
, value
);
1575 ssh2_pkt_adddata(pkt
, x
, 4);
1577 static void ssh2_pkt_addstring_start(struct Packet
*pkt
)
1579 ssh2_pkt_adduint32(pkt
, 0);
1580 pkt
->savedpos
= pkt
->length
;
1582 static void ssh2_pkt_addstring_str(struct Packet
*pkt
, char *data
)
1584 ssh2_pkt_adddata(pkt
, data
, strlen(data
));
1585 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1587 static void ssh2_pkt_addstring_data(struct Packet
*pkt
, char *data
, int len
)
1589 ssh2_pkt_adddata(pkt
, data
, len
);
1590 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1592 static void ssh2_pkt_addstring(struct Packet
*pkt
, char *data
)
1594 ssh2_pkt_addstring_start(pkt
);
1595 ssh2_pkt_addstring_str(pkt
, data
);
1597 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1600 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1601 p
= snewn(n
+ 1, unsigned char);
1603 fatalbox("out of memory");
1605 for (i
= 1; i
<= n
; i
++)
1606 p
[i
] = bignum_byte(b
, n
- i
);
1608 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1610 memmove(p
, p
+ i
, n
+ 1 - i
);
1614 static void ssh2_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1618 p
= ssh2_mpint_fmt(b
, &len
);
1619 ssh2_pkt_addstring_start(pkt
);
1620 ssh2_pkt_addstring_data(pkt
, (char *)p
, len
);
1625 * Construct an SSH2 final-form packet: compress it, encrypt it,
1626 * put the MAC on it. Final packet, ready to be sent, is stored in
1627 * pkt->data. Total length is returned.
1629 static int ssh2_pkt_construct(Ssh ssh
, struct Packet
*pkt
)
1631 int cipherblk
, maclen
, padding
, i
;
1634 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[5],
1635 ssh2_pkt_type(ssh
->pkt_ctx
, pkt
->data
[5]),
1636 pkt
->data
+ 6, pkt
->length
- 6,
1637 pkt
->nblanks
, pkt
->blanks
);
1638 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1642 * Compress packet payload.
1645 unsigned char *newpayload
;
1648 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, pkt
->data
+ 5,
1650 &newpayload
, &newlen
)) {
1652 ssh2_pkt_adddata(pkt
, newpayload
, newlen
);
1658 * Add padding. At least four bytes, and must also bring total
1659 * length (minus MAC) up to a multiple of the block size.
1661 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1662 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1665 (cipherblk
- (pkt
->length
+ padding
) % cipherblk
) % cipherblk
;
1666 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1667 ssh2_pkt_ensure(pkt
, pkt
->length
+ padding
+ maclen
);
1668 pkt
->data
[4] = padding
;
1669 for (i
= 0; i
< padding
; i
++)
1670 pkt
->data
[pkt
->length
+ i
] = random_byte();
1671 PUT_32BIT(pkt
->data
, pkt
->length
+ padding
- 4);
1673 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, pkt
->data
,
1674 pkt
->length
+ padding
,
1675 ssh
->v2_outgoing_sequence
);
1676 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1679 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1680 pkt
->data
, pkt
->length
+ padding
);
1682 pkt
->encrypted_len
= pkt
->length
+ padding
;
1684 /* Ready-to-send packet starts at pkt->data. We return length. */
1685 return pkt
->length
+ padding
+ maclen
;
1689 * Routines called from the main SSH code to send packets. There
1690 * are quite a few of these, because we have two separate
1691 * mechanisms for delaying the sending of packets:
1693 * - In order to send an IGNORE message and a password message in
1694 * a single fixed-length blob, we require the ability to
1695 * concatenate the encrypted forms of those two packets _into_ a
1696 * single blob and then pass it to our <network.h> transport
1697 * layer in one go. Hence, there's a deferment mechanism which
1698 * works after packet encryption.
1700 * - In order to avoid sending any connection-layer messages
1701 * during repeat key exchange, we have to queue up any such
1702 * outgoing messages _before_ they are encrypted (and in
1703 * particular before they're allocated sequence numbers), and
1704 * then send them once we've finished.
1706 * I call these mechanisms `defer' and `queue' respectively, so as
1707 * to distinguish them reasonably easily.
1709 * The functions send_noqueue() and defer_noqueue() free the packet
1710 * structure they are passed. Every outgoing packet goes through
1711 * precisely one of these functions in its life; packets passed to
1712 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1713 * these or get queued, and then when the queue is later emptied
1714 * the packets are all passed to defer_noqueue().
1718 * Send an SSH2 packet immediately, without queuing or deferring.
1720 static void ssh2_pkt_send_noqueue(Ssh ssh
, struct Packet
*pkt
)
1724 len
= ssh2_pkt_construct(ssh
, pkt
);
1725 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1726 if (backlog
> SSH_MAX_BACKLOG
)
1727 ssh_throttle_all(ssh
, 1, backlog
);
1729 ssh
->outgoing_data_size
+= pkt
->encrypted_len
;
1730 if (!ssh
->kex_in_progress
&&
1731 ssh
->max_data_size
!= 0 &&
1732 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1733 do_ssh2_transport(ssh
, "Initiating key re-exchange "
1734 "(too much data sent)", -1, NULL
);
1736 ssh_free_packet(pkt
);
1740 * Defer an SSH2 packet.
1742 static void ssh2_pkt_defer_noqueue(Ssh ssh
, struct Packet
*pkt
)
1744 int len
= ssh2_pkt_construct(ssh
, pkt
);
1745 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1746 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1747 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1751 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1752 ssh
->deferred_len
+= len
;
1753 ssh
->deferred_data_size
+= pkt
->encrypted_len
;
1754 ssh_free_packet(pkt
);
1758 * Queue an SSH2 packet.
1760 static void ssh2_pkt_queue(Ssh ssh
, struct Packet
*pkt
)
1762 assert(ssh
->queueing
);
1764 if (ssh
->queuelen
>= ssh
->queuesize
) {
1765 ssh
->queuesize
= ssh
->queuelen
+ 32;
1766 ssh
->queue
= sresize(ssh
->queue
, ssh
->queuesize
, struct Packet
*);
1769 ssh
->queue
[ssh
->queuelen
++] = pkt
;
1773 * Either queue or send a packet, depending on whether queueing is
1776 static void ssh2_pkt_send(Ssh ssh
, struct Packet
*pkt
)
1779 ssh2_pkt_queue(ssh
, pkt
);
1781 ssh2_pkt_send_noqueue(ssh
, pkt
);
1785 * Either queue or defer a packet, depending on whether queueing is
1788 static void ssh2_pkt_defer(Ssh ssh
, struct Packet
*pkt
)
1791 ssh2_pkt_queue(ssh
, pkt
);
1793 ssh2_pkt_defer_noqueue(ssh
, pkt
);
1797 * Send the whole deferred data block constructed by
1798 * ssh2_pkt_defer() or SSH1's defer_packet().
1800 * The expected use of the defer mechanism is that you call
1801 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1802 * not currently queueing, this simply sets up deferred_send_data
1803 * and then sends it. If we _are_ currently queueing, the calls to
1804 * ssh2_pkt_defer() put the deferred packets on to the queue
1805 * instead, and therefore ssh_pkt_defersend() has no deferred data
1806 * to send. Hence, there's no need to make it conditional on
1809 static void ssh_pkt_defersend(Ssh ssh
)
1812 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1814 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1815 sfree(ssh
->deferred_send_data
);
1816 ssh
->deferred_send_data
= NULL
;
1817 if (backlog
> SSH_MAX_BACKLOG
)
1818 ssh_throttle_all(ssh
, 1, backlog
);
1820 ssh
->outgoing_data_size
+= ssh
->deferred_data_size
;
1821 if (!ssh
->kex_in_progress
&&
1822 ssh
->max_data_size
!= 0 &&
1823 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1824 do_ssh2_transport(ssh
, "Initiating key re-exchange "
1825 "(too much data sent)", -1, NULL
);
1826 ssh
->deferred_data_size
= 0;
1830 * Send all queued SSH2 packets. We send them by means of
1831 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1832 * packets that needed to be lumped together.
1834 static void ssh2_pkt_queuesend(Ssh ssh
)
1838 assert(!ssh
->queueing
);
1840 for (i
= 0; i
< ssh
->queuelen
; i
++)
1841 ssh2_pkt_defer_noqueue(ssh
, ssh
->queue
[i
]);
1844 ssh_pkt_defersend(ssh
);
1848 void bndebug(char *string
, Bignum b
)
1852 p
= ssh2_mpint_fmt(b
, &len
);
1853 debug(("%s", string
));
1854 for (i
= 0; i
< len
; i
++)
1855 debug((" %02x", p
[i
]));
1861 static void sha_mpint(SHA_State
* s
, Bignum b
)
1865 p
= ssh2_mpint_fmt(b
, &len
);
1866 sha_string(s
, p
, len
);
1871 * Packet decode functions for both SSH1 and SSH2.
1873 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
)
1875 unsigned long value
;
1876 if (pkt
->length
- pkt
->savedpos
< 4)
1877 return 0; /* arrgh, no way to decline (FIXME?) */
1878 value
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1882 static int ssh2_pkt_getbool(struct Packet
*pkt
)
1884 unsigned long value
;
1885 if (pkt
->length
- pkt
->savedpos
< 1)
1886 return 0; /* arrgh, no way to decline (FIXME?) */
1887 value
= pkt
->body
[pkt
->savedpos
] != 0;
1891 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
)
1896 if (pkt
->length
- pkt
->savedpos
< 4)
1898 len
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1903 if (pkt
->length
- pkt
->savedpos
< *length
)
1905 *p
= (char *)(pkt
->body
+ pkt
->savedpos
);
1906 pkt
->savedpos
+= *length
;
1908 static void *ssh_pkt_getdata(struct Packet
*pkt
, int length
)
1910 if (pkt
->length
- pkt
->savedpos
< length
)
1912 pkt
->savedpos
+= length
;
1913 return pkt
->body
+ (pkt
->savedpos
- length
);
1915 static int ssh1_pkt_getrsakey(struct Packet
*pkt
, struct RSAKey
*key
,
1916 unsigned char **keystr
)
1920 j
= makekey(pkt
->body
+ pkt
->savedpos
,
1921 pkt
->length
- pkt
->savedpos
,
1928 assert(pkt
->savedpos
< pkt
->length
);
1932 static Bignum
ssh1_pkt_getmp(struct Packet
*pkt
)
1937 j
= ssh1_read_bignum(pkt
->body
+ pkt
->savedpos
,
1938 pkt
->length
- pkt
->savedpos
, &b
);
1946 static Bignum
ssh2_pkt_getmp(struct Packet
*pkt
)
1952 ssh_pkt_getstring(pkt
, &p
, &length
);
1957 b
= bignum_from_bytes((unsigned char *)p
, length
);
1962 * Helper function to add an SSH2 signature blob to a packet.
1963 * Expects to be shown the public key blob as well as the signature
1964 * blob. Normally works just like ssh2_pkt_addstring, but will
1965 * fiddle with the signature packet if necessary for
1966 * BUG_SSH2_RSA_PADDING.
1968 static void ssh2_add_sigblob(Ssh ssh
, struct Packet
*pkt
,
1969 void *pkblob_v
, int pkblob_len
,
1970 void *sigblob_v
, int sigblob_len
)
1972 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1973 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1975 /* dmemdump(pkblob, pkblob_len); */
1976 /* dmemdump(sigblob, sigblob_len); */
1979 * See if this is in fact an ssh-rsa signature and a buggy
1980 * server; otherwise we can just do this the easy way.
1982 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1983 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1984 int pos
, len
, siglen
;
1987 * Find the byte length of the modulus.
1990 pos
= 4+7; /* skip over "ssh-rsa" */
1991 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1992 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
1993 pos
+= 4; /* find modulus itself */
1994 while (len
> 0 && pkblob
[pos
] == 0)
1996 /* debug(("modulus length is %d\n", len)); */
1999 * Now find the signature integer.
2001 pos
= 4+7; /* skip over "ssh-rsa" */
2002 siglen
= GET_32BIT(sigblob
+pos
);
2003 /* debug(("signature length is %d\n", siglen)); */
2005 if (len
!= siglen
) {
2006 unsigned char newlen
[4];
2007 ssh2_pkt_addstring_start(pkt
);
2008 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, pos
);
2009 /* dmemdump(sigblob, pos); */
2010 pos
+= 4; /* point to start of actual sig */
2011 PUT_32BIT(newlen
, len
);
2012 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 4);
2013 /* dmemdump(newlen, 4); */
2015 while (len
-- > siglen
) {
2016 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 1);
2017 /* dmemdump(newlen, 1); */
2019 ssh2_pkt_addstring_data(pkt
, (char *)(sigblob
+pos
), siglen
);
2020 /* dmemdump(sigblob+pos, siglen); */
2024 /* Otherwise fall through and do it the easy way. */
2027 ssh2_pkt_addstring_start(pkt
);
2028 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, sigblob_len
);
2032 * Examine the remote side's version string and compare it against
2033 * a list of known buggy implementations.
2035 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
2037 char *imp
; /* pointer to implementation part */
2039 imp
+= strcspn(imp
, "-");
2041 imp
+= strcspn(imp
, "-");
2044 ssh
->remote_bugs
= 0;
2046 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
2047 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
2048 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
2049 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
2050 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
2051 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
2053 * These versions don't support SSH1_MSG_IGNORE, so we have
2054 * to use a different defence against password length
2057 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
2058 logevent("We believe remote version has SSH1 ignore bug");
2061 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
2062 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
2063 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
2065 * These versions need a plain password sent; they can't
2066 * handle having a null and a random length of data after
2069 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
2070 logevent("We believe remote version needs a plain SSH1 password");
2073 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
2074 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
2075 (!strcmp(imp
, "Cisco-1.25")))) {
2077 * These versions apparently have no clue whatever about
2078 * RSA authentication and will panic and die if they see
2079 * an AUTH_RSA message.
2081 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
2082 logevent("We believe remote version can't handle RSA authentication");
2085 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
2086 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
2087 !wc_match("* VShell", imp
) &&
2088 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
2089 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
2090 wc_match("2.1 *", imp
)))) {
2092 * These versions have the HMAC bug.
2094 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
2095 logevent("We believe remote version has SSH2 HMAC bug");
2098 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2099 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2100 !wc_match("* VShell", imp
) &&
2101 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2103 * These versions have the key-derivation bug (failing to
2104 * include the literal shared secret in the hashes that
2105 * generate the keys).
2107 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2108 logevent("We believe remote version has SSH2 key-derivation bug");
2111 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2112 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2113 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2114 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2116 * These versions have the SSH2 RSA padding bug.
2118 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2119 logevent("We believe remote version has SSH2 RSA padding bug");
2122 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2123 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2124 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2126 * These versions have the SSH2 session-ID bug in
2127 * public-key authentication.
2129 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2130 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2135 * The `software version' part of an SSH version string is required
2136 * to contain no spaces or minus signs.
2138 static void ssh_fix_verstring(char *str
)
2140 /* Eat "SSH-<protoversion>-". */
2141 assert(*str
== 'S'); str
++;
2142 assert(*str
== 'S'); str
++;
2143 assert(*str
== 'H'); str
++;
2144 assert(*str
== '-'); str
++;
2145 while (*str
&& *str
!= '-') str
++;
2146 assert(*str
== '-'); str
++;
2148 /* Convert minus signs and spaces in the remaining string into
2151 if (*str
== '-' || *str
== ' ')
2157 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2159 struct do_ssh_init_state
{
2167 crState(do_ssh_init_state
);
2169 crBegin(ssh
->do_ssh_init_crstate
);
2171 /* Search for the string "SSH-" in the input. */
2174 static const int transS
[] = { 1, 2, 2, 1 };
2175 static const int transH
[] = { 0, 0, 3, 0 };
2176 static const int transminus
[] = { 0, 0, 0, -1 };
2178 s
->i
= transS
[s
->i
];
2180 s
->i
= transH
[s
->i
];
2182 s
->i
= transminus
[s
->i
];
2187 crReturn(1); /* get another character */
2191 s
->vstring
= snewn(s
->vstrsize
, char);
2192 strcpy(s
->vstring
, "SSH-");
2196 crReturn(1); /* get another char */
2197 if (s
->vslen
>= s
->vstrsize
- 1) {
2199 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2201 s
->vstring
[s
->vslen
++] = c
;
2204 s
->version
[s
->i
] = '\0';
2206 } else if (s
->i
< sizeof(s
->version
) - 1)
2207 s
->version
[s
->i
++] = c
;
2208 } else if (c
== '\012')
2212 ssh
->agentfwd_enabled
= FALSE
;
2213 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2215 s
->vstring
[s
->vslen
] = 0;
2216 s
->vstring
[strcspn(s
->vstring
, "\015\012")] = '\0';/* remove EOL chars */
2219 vlog
= snewn(20 + s
->vslen
, char);
2220 sprintf(vlog
, "Server version: %s", s
->vstring
);
2224 ssh_detect_bugs(ssh
, s
->vstring
);
2227 * Decide which SSH protocol version to support.
2230 /* Anything strictly below "2.0" means protocol 1 is supported. */
2231 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2232 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2233 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2235 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2236 bombout(("SSH protocol version 1 required by user but not provided by server"));
2239 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2240 bombout(("SSH protocol version 2 required by user but not provided by server"));
2247 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2249 * Construct a v2 version string.
2251 verstring
= dupprintf("SSH-2.0-%s\015\012", sshver
);
2255 * Construct a v1 version string.
2257 verstring
= dupprintf("SSH-%s-%s\012",
2258 (ssh_versioncmp(s
->version
, "1.5") <= 0 ?
2259 s
->version
: "1.5"),
2264 ssh_fix_verstring(verstring
);
2266 if (ssh
->version
== 2) {
2268 * Hash our version string and their version string.
2270 SHA_Init(&ssh
->exhashbase
);
2271 sha_string(&ssh
->exhashbase
, verstring
,
2272 strcspn(verstring
, "\015\012"));
2273 sha_string(&ssh
->exhashbase
, s
->vstring
,
2274 strcspn(s
->vstring
, "\015\012"));
2277 * Initialise SSHv2 protocol.
2279 ssh
->protocol
= ssh2_protocol
;
2280 ssh2_protocol_setup(ssh
);
2281 ssh
->s_rdpkt
= ssh2_rdpkt
;
2284 * Initialise SSHv1 protocol.
2286 ssh
->protocol
= ssh1_protocol
;
2287 ssh1_protocol_setup(ssh
);
2288 ssh
->s_rdpkt
= ssh1_rdpkt
;
2290 logeventf(ssh
, "We claim version: %.*s",
2291 strcspn(verstring
, "\015\012"), verstring
);
2292 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2296 logeventf(ssh
, "Using SSH protocol version %d", ssh
->version
);
2298 update_specials_menu(ssh
->frontend
);
2299 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2300 ssh
->pinger
= pinger_new(&ssh
->cfg
, &ssh_backend
, ssh
);
2307 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2309 crBegin(ssh
->ssh_gotdata_crstate
);
2312 * To begin with, feed the characters one by one to the
2313 * protocol initialisation / selection function do_ssh_init().
2314 * When that returns 0, we're done with the initial greeting
2315 * exchange and can move on to packet discipline.
2318 int ret
; /* need not be kept across crReturn */
2320 crReturnV
; /* more data please */
2321 ret
= do_ssh_init(ssh
, *data
);
2329 * We emerge from that loop when the initial negotiation is
2330 * over and we have selected an s_rdpkt function. Now pass
2331 * everything to s_rdpkt, and then pass the resulting packets
2332 * to the proper protocol handler.
2337 while (datalen
> 0) {
2338 struct Packet
*pktin
= ssh
->s_rdpkt(ssh
, &data
, &datalen
);
2340 ssh
->protocol(ssh
, NULL
, 0, pktin
);
2341 ssh_free_packet(pktin
);
2343 if (ssh
->state
== SSH_STATE_CLOSED
)
2351 static void ssh_do_close(Ssh ssh
)
2354 struct ssh_channel
*c
;
2356 ssh
->state
= SSH_STATE_CLOSED
;
2360 notify_remote_exit(ssh
->frontend
);
2363 * Now we must shut down any port and X forwardings going
2364 * through this connection.
2366 if (ssh
->channels
) {
2367 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2370 x11_close(c
->u
.x11
.s
);
2373 pfd_close(c
->u
.pfd
.s
);
2376 del234(ssh
->channels
, c
);
2377 if (ssh
->version
== 2)
2378 bufchain_clear(&c
->v
.v2
.outbuffer
);
2384 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2387 Ssh ssh
= (Ssh
) plug
;
2390 /* A socket error has occurred. */
2391 logevent(error_msg
);
2392 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2394 /* Otherwise, the remote side closed the connection normally. */
2399 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2401 Ssh ssh
= (Ssh
) plug
;
2402 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2403 if (ssh
->state
== SSH_STATE_CLOSED
) {
2410 static void ssh_sent(Plug plug
, int bufsize
)
2412 Ssh ssh
= (Ssh
) plug
;
2414 * If the send backlog on the SSH socket itself clears, we
2415 * should unthrottle the whole world if it was throttled.
2417 if (bufsize
< SSH_MAX_BACKLOG
)
2418 ssh_throttle_all(ssh
, 0, bufsize
);
2422 * Connect to specified host and port.
2423 * Returns an error message, or NULL on success.
2424 * Also places the canonical host name into `realhost'. It must be
2425 * freed by the caller.
2427 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2428 char **realhost
, int nodelay
, int keepalive
)
2430 static const struct plug_function_table fn_table
= {
2440 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2441 if (!ssh
->savedhost
)
2442 fatalbox("Out of memory");
2443 strcpy(ssh
->savedhost
, host
);
2446 port
= 22; /* default ssh port */
2447 ssh
->savedport
= port
;
2452 logeventf(ssh
, "Looking up host \"%s\"", host
);
2453 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
);
2454 if ((err
= sk_addr_error(addr
)) != NULL
) {
2464 sk_getaddr(addr
, addrbuf
, 100);
2465 logeventf(ssh
, "Connecting to %s port %d", addrbuf
, port
);
2467 ssh
->fn
= &fn_table
;
2468 ssh
->s
= new_connection(addr
, *realhost
, port
,
2469 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2470 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2472 notify_remote_exit(ssh
->frontend
);
2480 * Throttle or unthrottle the SSH connection.
2482 static void ssh1_throttle(Ssh ssh
, int adjust
)
2484 int old_count
= ssh
->v1_throttle_count
;
2485 ssh
->v1_throttle_count
+= adjust
;
2486 assert(ssh
->v1_throttle_count
>= 0);
2487 if (ssh
->v1_throttle_count
&& !old_count
) {
2488 sk_set_frozen(ssh
->s
, 1);
2489 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2490 sk_set_frozen(ssh
->s
, 0);
2495 * Throttle or unthrottle _all_ local data streams (for when sends
2496 * on the SSH connection itself back up).
2498 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2501 struct ssh_channel
*c
;
2503 if (enable
== ssh
->throttled_all
)
2505 ssh
->throttled_all
= enable
;
2506 ssh
->overall_bufsize
= bufsize
;
2509 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2511 case CHAN_MAINSESSION
:
2513 * This is treated separately, outside the switch.
2517 x11_override_throttle(c
->u
.x11
.s
, enable
);
2520 /* Agent channels require no buffer management. */
2523 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2530 * Username and password input, abstracted off into routines
2531 * reusable in several places - even between SSH1 and SSH2.
2534 /* Set up a username or password input loop on a given buffer. */
2535 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2537 ssh
->userpass_input_buffer
= buffer
;
2538 ssh
->userpass_input_buflen
= buflen
;
2539 ssh
->userpass_input_bufpos
= 0;
2540 ssh
->userpass_input_echo
= echo
;
2544 * Process some terminal data in the course of username/password
2545 * input. Returns >0 for success (line of input returned in
2546 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2547 * for inconclusive (keep waiting for more input please).
2549 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2554 switch (c
= *in
++) {
2557 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2558 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2563 if (ssh
->userpass_input_bufpos
> 0) {
2564 if (ssh
->userpass_input_echo
)
2565 c_write_str(ssh
, "\b \b");
2566 ssh
->userpass_input_bufpos
--;
2571 while (ssh
->userpass_input_bufpos
> 0) {
2572 if (ssh
->userpass_input_echo
)
2573 c_write_str(ssh
, "\b \b");
2574 ssh
->userpass_input_bufpos
--;
2583 * This simplistic check for printability is disabled
2584 * when we're doing password input, because some people
2585 * have control characters in their passwords.o
2587 if ((!ssh
->userpass_input_echo
||
2588 (c
>= ' ' && c
<= '~') ||
2589 ((unsigned char) c
>= 160))
2590 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2591 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2592 if (ssh
->userpass_input_echo
)
2593 c_write(ssh
, &c
, 1);
2601 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2603 Ssh ssh
= (Ssh
) sshv
;
2605 ssh
->agent_response
= reply
;
2606 ssh
->agent_response_len
= replylen
;
2608 if (ssh
->version
== 1)
2609 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2611 do_ssh2_authconn(ssh
, NULL
, -1, NULL
);
2614 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2616 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2618 void *sentreply
= reply
;
2621 /* Fake SSH_AGENT_FAILURE. */
2622 sentreply
= "\0\0\0\1\5";
2625 if (ssh
->version
== 2) {
2626 ssh2_add_channel_data(c
, sentreply
, replylen
);
2629 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2630 PKT_INT
, c
->remoteid
,
2633 PKT_DATA
, sentreply
, replylen
,
2642 * Handle the key exchange and user authentication phases.
2644 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
2645 struct Packet
*pktin
)
2648 unsigned char cookie
[8], *ptr
;
2649 struct RSAKey servkey
, hostkey
;
2650 struct MD5Context md5c
;
2651 struct do_ssh1_login_state
{
2653 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2654 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2655 int tried_publickey
, tried_agent
;
2656 int tis_auth_refused
, ccard_auth_refused
;
2657 unsigned char session_id
[16];
2660 void *publickey_blob
;
2661 int publickey_bloblen
;
2667 unsigned char request
[5], *response
, *p
;
2676 crState(do_ssh1_login_state
);
2678 crBegin(ssh
->do_ssh1_login_crstate
);
2683 if (pktin
->type
!= SSH1_SMSG_PUBLIC_KEY
) {
2684 bombout(("Public key packet not received"));
2688 logevent("Received public keys");
2690 ptr
= ssh_pkt_getdata(pktin
, 8);
2692 bombout(("SSH1 public key packet stopped before random cookie"));
2695 memcpy(cookie
, ptr
, 8);
2697 if (!ssh1_pkt_getrsakey(pktin
, &servkey
, &s
->keystr1
) ||
2698 !ssh1_pkt_getrsakey(pktin
, &hostkey
, &s
->keystr2
)) {
2699 bombout(("Failed to read SSH1 public keys from public key packet"));
2704 * Log the host key fingerprint.
2708 logevent("Host key fingerprint is:");
2709 strcpy(logmsg
, " ");
2710 hostkey
.comment
= NULL
;
2711 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2712 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2716 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(pktin
);
2717 s
->supported_ciphers_mask
= ssh_pkt_getuint32(pktin
);
2718 s
->supported_auths_mask
= ssh_pkt_getuint32(pktin
);
2720 ssh
->v1_local_protoflags
=
2721 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2722 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2725 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2726 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2727 MD5Update(&md5c
, cookie
, 8);
2728 MD5Final(s
->session_id
, &md5c
);
2730 for (i
= 0; i
< 32; i
++)
2731 ssh
->session_key
[i
] = random_byte();
2734 * Verify that the `bits' and `bytes' parameters match.
2736 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
2737 servkey
.bits
> servkey
.bytes
* 8) {
2738 bombout(("SSH1 public keys were badly formatted"));
2742 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2744 s
->rsabuf
= snewn(s
->len
, unsigned char);
2746 fatalbox("Out of memory");
2749 * Verify the host key.
2753 * First format the key into a string.
2755 int len
= rsastr_len(&hostkey
);
2756 char fingerprint
[100];
2757 char *keystr
= snewn(len
, char);
2759 fatalbox("Out of memory");
2760 rsastr_fmt(keystr
, &hostkey
);
2761 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2762 verify_ssh_host_key(ssh
->frontend
,
2763 ssh
->savedhost
, ssh
->savedport
, "rsa", keystr
,
2768 for (i
= 0; i
< 32; i
++) {
2769 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2771 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2774 if (hostkey
.bytes
> servkey
.bytes
) {
2775 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
2777 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2779 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2781 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2784 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2788 logevent("Encrypted session key");
2791 int cipher_chosen
= 0, warn
= 0;
2792 char *cipher_string
= NULL
;
2794 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2795 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
2796 if (next_cipher
== CIPHER_WARN
) {
2797 /* If/when we choose a cipher, warn about it */
2799 } else if (next_cipher
== CIPHER_AES
) {
2800 /* XXX Probably don't need to mention this. */
2801 logevent("AES not supported in SSH1, skipping");
2803 switch (next_cipher
) {
2804 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2805 cipher_string
= "3DES"; break;
2806 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2807 cipher_string
= "Blowfish"; break;
2808 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2809 cipher_string
= "single-DES"; break;
2811 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2815 if (!cipher_chosen
) {
2816 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2817 bombout(("Server violates SSH 1 protocol by not "
2818 "supporting 3DES encryption"));
2820 /* shouldn't happen */
2821 bombout(("No supported ciphers found"));
2825 /* Warn about chosen cipher if necessary. */
2827 askalg(ssh
->frontend
, "cipher", cipher_string
);
2830 switch (s
->cipher_type
) {
2831 case SSH_CIPHER_3DES
:
2832 logevent("Using 3DES encryption");
2834 case SSH_CIPHER_DES
:
2835 logevent("Using single-DES encryption");
2837 case SSH_CIPHER_BLOWFISH
:
2838 logevent("Using Blowfish encryption");
2842 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
2843 PKT_CHAR
, s
->cipher_type
,
2844 PKT_DATA
, cookie
, 8,
2845 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
2846 PKT_DATA
, s
->rsabuf
, s
->len
,
2847 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
2849 logevent("Trying to enable encryption...");
2853 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2854 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
2856 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
2857 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
2858 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
2860 ssh
->crcda_ctx
= crcda_make_context();
2861 logevent("Installing CRC compensation attack detector");
2863 if (servkey
.modulus
) {
2864 sfree(servkey
.modulus
);
2865 servkey
.modulus
= NULL
;
2867 if (servkey
.exponent
) {
2868 sfree(servkey
.exponent
);
2869 servkey
.exponent
= NULL
;
2871 if (hostkey
.modulus
) {
2872 sfree(hostkey
.modulus
);
2873 hostkey
.modulus
= NULL
;
2875 if (hostkey
.exponent
) {
2876 sfree(hostkey
.exponent
);
2877 hostkey
.exponent
= NULL
;
2881 if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
2882 bombout(("Encryption not successfully enabled"));
2886 logevent("Successfully started encryption");
2890 if (!*ssh
->cfg
.username
) {
2891 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2892 if (!ssh_get_line("login as: ",
2893 s
->username
, sizeof(s
->username
), FALSE
)) {
2895 * get_line failed to get a username.
2898 logevent("No username provided. Abandoning session.");
2899 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2903 int ret
; /* need not be kept over crReturn */
2904 c_write_str(ssh
, "login as: ");
2907 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
2909 crWaitUntil(!pktin
);
2910 ret
= process_userpass_input(ssh
, in
, inlen
);
2914 c_write_str(ssh
, "\r\n");
2917 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
2918 s
->username
[sizeof(s
->username
)-1] = '\0';
2921 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
2923 char userlog
[22 + sizeof(s
->username
)];
2924 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
2926 if (flags
& FLAG_INTERACTIVE
&&
2927 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2928 strcat(userlog
, "\r\n");
2929 c_write_str(ssh
, userlog
);
2936 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2937 /* We must not attempt PK auth. Pretend we've already tried it. */
2938 s
->tried_publickey
= s
->tried_agent
= 1;
2940 s
->tried_publickey
= s
->tried_agent
= 0;
2942 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
2943 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
2944 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
2945 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
2946 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
2947 s
->publickey_blob
= NULL
;
2949 s
->publickey_blob
= NULL
;
2951 while (pktin
->type
== SSH1_SMSG_FAILURE
) {
2952 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2954 if (agent_exists() && !s
->tried_agent
) {
2956 * Attempt RSA authentication using Pageant.
2962 logevent("Pageant is running. Requesting keys.");
2964 /* Request the keys held by the agent. */
2965 PUT_32BIT(s
->request
, 1);
2966 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2967 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
2968 ssh_agent_callback
, ssh
)) {
2972 bombout(("Unexpected data from server while waiting"
2973 " for agent response"));
2976 } while (pktin
|| inlen
> 0);
2977 r
= ssh
->agent_response
;
2978 s
->responselen
= ssh
->agent_response_len
;
2980 s
->response
= (unsigned char *) r
;
2981 if (s
->response
&& s
->responselen
>= 5 &&
2982 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
2983 s
->p
= s
->response
+ 5;
2984 s
->nkeys
= GET_32BIT(s
->p
);
2988 sprintf(buf
, "Pageant has %d SSH1 keys", s
->nkeys
);
2991 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
2994 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
2997 if (s
->publickey_blob
&&
2998 !memcmp(s
->p
, s
->publickey_blob
,
2999 s
->publickey_bloblen
)) {
3000 logevent("This key matches configured key file");
3001 s
->tried_publickey
= 1;
3006 do { /* do while (0) to make breaking easy */
3007 n
= ssh1_read_bignum
3008 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3013 n
= ssh1_read_bignum
3014 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3019 if (s
->responselen
- (s
->p
-s
->response
) < 4)
3021 s
->commentlen
= GET_32BIT(s
->p
);
3023 if (s
->responselen
- (s
->p
-s
->response
) <
3026 s
->commentp
= (char *)s
->p
;
3027 s
->p
+= s
->commentlen
;
3031 logevent("Pageant key list packet was truncated");
3035 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3036 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3038 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3039 logevent("Key refused");
3042 logevent("Received RSA challenge");
3043 if ((s
->challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3044 bombout(("Server's RSA challenge was badly formatted"));
3049 char *agentreq
, *q
, *ret
;
3052 len
= 1 + 4; /* message type, bit count */
3053 len
+= ssh1_bignum_length(s
->key
.exponent
);
3054 len
+= ssh1_bignum_length(s
->key
.modulus
);
3055 len
+= ssh1_bignum_length(s
->challenge
);
3056 len
+= 16; /* session id */
3057 len
+= 4; /* response format */
3058 agentreq
= snewn(4 + len
, char);
3059 PUT_32BIT(agentreq
, len
);
3061 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
3062 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
3064 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
3065 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
3066 q
+= ssh1_write_bignum(q
, s
->challenge
);
3067 memcpy(q
, s
->session_id
, 16);
3069 PUT_32BIT(q
, 1); /* response format */
3070 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
3071 ssh_agent_callback
, ssh
)) {
3076 bombout(("Unexpected data from server"
3077 " while waiting for agent"
3081 } while (pktin
|| inlen
> 0);
3082 vret
= ssh
->agent_response
;
3083 retlen
= ssh
->agent_response_len
;
3088 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
3089 logevent("Sending Pageant's response");
3090 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3091 PKT_DATA
, ret
+ 5, 16,
3095 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
3097 ("Pageant's response accepted");
3098 if (flags
& FLAG_VERBOSE
) {
3099 c_write_str(ssh
, "Authenticated using"
3101 c_write(ssh
, s
->commentp
,
3103 c_write_str(ssh
, "\" from agent\r\n");
3108 ("Pageant's response not accepted");
3111 ("Pageant failed to answer challenge");
3115 logevent("No reply received from Pageant");
3118 freebn(s
->key
.exponent
);
3119 freebn(s
->key
.modulus
);
3120 freebn(s
->challenge
);
3129 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
3130 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
3132 if (ssh
->cfg
.try_tis_auth
&&
3133 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3134 !s
->tis_auth_refused
) {
3135 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3136 logevent("Requested TIS authentication");
3137 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3139 if (pktin
->type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3140 logevent("TIS authentication declined");
3141 if (flags
& FLAG_INTERACTIVE
)
3142 c_write_str(ssh
, "TIS authentication refused.\r\n");
3143 s
->tis_auth_refused
= 1;
3149 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3151 bombout(("TIS challenge packet was badly formed"));
3154 logevent("Received TIS challenge");
3155 if (challengelen
> sizeof(s
->prompt
) - 1)
3156 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3157 memcpy(s
->prompt
, challenge
, challengelen
);
3158 /* Prompt heuristic comes from OpenSSH */
3159 strncpy(s
->prompt
+ challengelen
,
3160 memchr(s
->prompt
, '\n', challengelen
) ?
3161 "": "\r\nResponse: ",
3162 (sizeof s
->prompt
) - challengelen
);
3163 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
3166 if (ssh
->cfg
.try_tis_auth
&&
3167 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3168 !s
->ccard_auth_refused
) {
3169 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3170 logevent("Requested CryptoCard authentication");
3171 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3173 if (pktin
->type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3174 logevent("CryptoCard authentication declined");
3175 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3176 s
->ccard_auth_refused
= 1;
3182 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3184 bombout(("CryptoCard challenge packet was badly formed"));
3187 logevent("Received CryptoCard challenge");
3188 if (challengelen
> sizeof(s
->prompt
) - 1)
3189 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3190 memcpy(s
->prompt
, challenge
, challengelen
);
3191 strncpy(s
->prompt
+ challengelen
,
3192 memchr(s
->prompt
, '\n', challengelen
) ?
3193 "" : "\r\nResponse: ",
3194 sizeof(s
->prompt
) - challengelen
);
3195 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
3198 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3199 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
3200 s
->username
, ssh
->savedhost
);
3202 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3203 char *comment
= NULL
;
3206 if (flags
& FLAG_VERBOSE
)
3207 c_write_str(ssh
, "Trying public key authentication.\r\n");
3208 logeventf(ssh
, "Trying public key \"%s\"",
3209 filename_to_str(&ssh
->cfg
.keyfile
));
3210 type
= key_type(&ssh
->cfg
.keyfile
);
3211 if (type
!= SSH_KEYTYPE_SSH1
) {
3212 sprintf(msgbuf
, "Key is of wrong type (%s)",
3213 key_type_to_str(type
));
3215 c_write_str(ssh
, msgbuf
);
3216 c_write_str(ssh
, "\r\n");
3217 s
->tried_publickey
= 1;
3220 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
3221 if (flags
& FLAG_VERBOSE
)
3222 c_write_str(ssh
, "No passphrase required.\r\n");
3225 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
3230 * Show password prompt, having first obtained it via a TIS
3231 * or CryptoCard exchange if we're doing TIS or CryptoCard
3235 if (!ssh_get_line(s
->prompt
, s
->password
,
3236 sizeof(s
->password
), TRUE
)) {
3238 * get_line failed to get a password (for example
3239 * because one was supplied on the command line
3240 * which has already failed to work). Terminate.
3242 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
3243 PKT_STR
, "No more passwords available to try",
3245 logevent("Unable to authenticate");
3246 connection_fatal(ssh
->frontend
, "Unable to authenticate");
3247 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3251 /* Prompt may have come from server. We've munged it a bit, so
3252 * we know it to be zero-terminated at least once. */
3253 int ret
; /* need not be saved over crReturn */
3254 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3257 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3259 crWaitUntil(!pktin
);
3260 ret
= process_userpass_input(ssh
, in
, inlen
);
3264 c_write_str(ssh
, "\r\n");
3268 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3270 * Try public key authentication with the specified
3273 s
->tried_publickey
= 1;
3276 const char *error
= NULL
;
3277 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3280 c_write_str(ssh
, "Couldn't load private key from ");
3281 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3282 c_write_str(ssh
, " (");
3283 c_write_str(ssh
, error
);
3284 c_write_str(ssh
, ").\r\n");
3285 continue; /* go and try password */
3288 c_write_str(ssh
, "Wrong passphrase.\r\n");
3289 s
->tried_publickey
= 0;
3290 continue; /* try again */
3295 * Send a public key attempt.
3297 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3298 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3301 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3302 c_write_str(ssh
, "Server refused our public key.\r\n");
3303 continue; /* go and try password */
3305 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3306 bombout(("Bizarre response to offer of public key"));
3312 unsigned char buffer
[32];
3313 Bignum challenge
, response
;
3315 if ((challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3316 bombout(("Server's RSA challenge was badly formatted"));
3319 response
= rsadecrypt(challenge
, &s
->key
);
3320 freebn(s
->key
.private_exponent
);/* burn the evidence */
3322 for (i
= 0; i
< 32; i
++) {
3323 buffer
[i
] = bignum_byte(response
, 31 - i
);
3327 MD5Update(&md5c
, buffer
, 32);
3328 MD5Update(&md5c
, s
->session_id
, 16);
3329 MD5Final(buffer
, &md5c
);
3331 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3332 PKT_DATA
, buffer
, 16, PKT_END
);
3339 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3340 if (flags
& FLAG_VERBOSE
)
3341 c_write_str(ssh
, "Failed to authenticate with"
3342 " our public key.\r\n");
3343 continue; /* go and try password */
3344 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3345 bombout(("Bizarre response to RSA authentication response"));
3349 break; /* we're through! */
3351 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3353 * Defence against traffic analysis: we send a
3354 * whole bunch of packets containing strings of
3355 * different lengths. One of these strings is the
3356 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3357 * The others are all random data in
3358 * SSH1_MSG_IGNORE packets. This way a passive
3359 * listener can't tell which is the password, and
3360 * hence can't deduce the password length.
3362 * Anybody with a password length greater than 16
3363 * bytes is going to have enough entropy in their
3364 * password that a listener won't find it _that_
3365 * much help to know how long it is. So what we'll
3368 * - if password length < 16, we send 15 packets
3369 * containing string lengths 1 through 15
3371 * - otherwise, we let N be the nearest multiple
3372 * of 8 below the password length, and send 8
3373 * packets containing string lengths N through
3374 * N+7. This won't obscure the order of
3375 * magnitude of the password length, but it will
3376 * introduce a bit of extra uncertainty.
3378 * A few servers (the old 1.2.18 through 1.2.22)
3379 * can't deal with SSH1_MSG_IGNORE. For these
3380 * servers, we need an alternative defence. We make
3381 * use of the fact that the password is interpreted
3382 * as a C string: so we can append a NUL, then some
3385 * One server (a Cisco one) can deal with neither
3386 * SSH1_MSG_IGNORE _nor_ a padded password string.
3387 * For this server we are left with no defences
3388 * against password length sniffing.
3390 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3392 * The server can deal with SSH1_MSG_IGNORE, so
3393 * we can use the primary defence.
3395 int bottom
, top
, pwlen
, i
;
3398 pwlen
= strlen(s
->password
);
3400 bottom
= 0; /* zero length passwords are OK! :-) */
3403 bottom
= pwlen
& ~7;
3407 assert(pwlen
>= bottom
&& pwlen
<= top
);
3409 randomstr
= snewn(top
+ 1, char);
3411 for (i
= bottom
; i
<= top
; i
++) {
3413 defer_packet(ssh
, s
->pwpkt_type
,
3414 PKTT_PASSWORD
, PKT_STR
, s
->password
,
3415 PKTT_OTHER
, PKT_END
);
3417 for (j
= 0; j
< i
; j
++) {
3419 randomstr
[j
] = random_byte();
3420 } while (randomstr
[j
] == '\0');
3422 randomstr
[i
] = '\0';
3423 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3424 PKT_STR
, randomstr
, PKT_END
);
3427 logevent("Sending password with camouflage packets");
3428 ssh_pkt_defersend(ssh
);
3431 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3433 * The server can't deal with SSH1_MSG_IGNORE
3434 * but can deal with padded passwords, so we
3435 * can use the secondary defence.
3441 len
= strlen(s
->password
);
3442 if (len
< sizeof(string
)) {
3444 strcpy(string
, s
->password
);
3445 len
++; /* cover the zero byte */
3446 while (len
< sizeof(string
)) {
3447 string
[len
++] = (char) random_byte();
3452 logevent("Sending length-padded password");
3453 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3454 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3455 PKTT_OTHER
, PKT_END
);
3458 * The server has _both_
3459 * BUG_CHOKES_ON_SSH1_IGNORE and
3460 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3461 * therefore nothing we can do.
3464 len
= strlen(s
->password
);
3465 logevent("Sending unpadded password");
3466 send_packet(ssh
, s
->pwpkt_type
,
3467 PKTT_PASSWORD
, PKT_INT
, len
,
3468 PKT_DATA
, s
->password
, len
,
3469 PKTT_OTHER
, PKT_END
);
3472 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3473 PKT_STR
, s
->password
, PKTT_OTHER
, PKT_END
);
3476 logevent("Sent password");
3477 memset(s
->password
, 0, strlen(s
->password
));
3479 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3480 if (flags
& FLAG_VERBOSE
)
3481 c_write_str(ssh
, "Access denied\r\n");
3482 logevent("Authentication refused");
3483 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3484 bombout(("Strange packet received, type %d", pktin
->type
));
3489 logevent("Authentication successful");
3494 void sshfwd_close(struct ssh_channel
*c
)
3498 if (ssh
->state
!= SSH_STATE_SESSION
) {
3499 assert(ssh
->state
== SSH_STATE_CLOSED
);
3503 if (c
&& !c
->closes
) {
3505 * If the channel's remoteid is -1, we have sent
3506 * CHANNEL_OPEN for this channel, but it hasn't even been
3507 * acknowledged by the server. So we must set a close flag
3508 * on it now, and then when the server acks the channel
3509 * open, we can close it then.
3511 if (((int)c
->remoteid
) != -1) {
3512 if (ssh
->version
== 1) {
3513 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3516 struct Packet
*pktout
;
3517 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3518 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
3519 ssh2_pkt_send(ssh
, pktout
);
3522 c
->closes
= 1; /* sent MSG_CLOSE */
3523 if (c
->type
== CHAN_X11
) {
3525 logevent("Forwarded X11 connection terminated");
3526 } else if (c
->type
== CHAN_SOCKDATA
||
3527 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3529 logevent("Forwarded port closed");
3534 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3538 if (ssh
->state
!= SSH_STATE_SESSION
) {
3539 assert(ssh
->state
== SSH_STATE_CLOSED
);
3543 if (ssh
->version
== 1) {
3544 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3545 PKT_INT
, c
->remoteid
,
3547 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3548 PKTT_OTHER
, PKT_END
);
3550 * In SSH1 we can return 0 here - implying that forwarded
3551 * connections are never individually throttled - because
3552 * the only circumstance that can cause throttling will be
3553 * the whole SSH connection backing up, in which case
3554 * _everything_ will be throttled as a whole.
3558 ssh2_add_channel_data(c
, buf
, len
);
3559 return ssh2_try_send(c
);
3563 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3567 if (ssh
->state
!= SSH_STATE_SESSION
) {
3568 assert(ssh
->state
== SSH_STATE_CLOSED
);
3572 if (ssh
->version
== 1) {
3573 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3574 c
->v
.v1
.throttling
= 0;
3575 ssh1_throttle(ssh
, -1);
3578 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3582 static void ssh_queueing_handler(Ssh ssh
, struct Packet
*pktin
)
3584 struct queued_handler
*qh
= ssh
->qhead
;
3588 assert(pktin
->type
== qh
->msg1
|| pktin
->type
== qh
->msg2
);
3591 assert(ssh
->packet_dispatch
[qh
->msg1
] == ssh_queueing_handler
);
3592 ssh
->packet_dispatch
[qh
->msg1
] = NULL
;
3595 assert(ssh
->packet_dispatch
[qh
->msg2
] == ssh_queueing_handler
);
3596 ssh
->packet_dispatch
[qh
->msg2
] = NULL
;
3600 ssh
->qhead
= qh
->next
;
3602 if (ssh
->qhead
->msg1
> 0) {
3603 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg1
] == NULL
);
3604 ssh
->packet_dispatch
[ssh
->qhead
->msg1
] = ssh_queueing_handler
;
3606 if (ssh
->qhead
->msg2
> 0) {
3607 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg2
] == NULL
);
3608 ssh
->packet_dispatch
[ssh
->qhead
->msg2
] = ssh_queueing_handler
;
3611 ssh
->qhead
= ssh
->qtail
= NULL
;
3612 ssh
->packet_dispatch
[pktin
->type
] = NULL
;
3615 qh
->handler(ssh
, pktin
, qh
->ctx
);
3620 static void ssh_queue_handler(Ssh ssh
, int msg1
, int msg2
,
3621 chandler_fn_t handler
, void *ctx
)
3623 struct queued_handler
*qh
;
3625 qh
= snew(struct queued_handler
);
3628 qh
->handler
= handler
;
3632 if (ssh
->qtail
== NULL
) {
3636 assert(ssh
->packet_dispatch
[qh
->msg1
] == NULL
);
3637 ssh
->packet_dispatch
[qh
->msg1
] = ssh_queueing_handler
;
3640 assert(ssh
->packet_dispatch
[qh
->msg2
] == NULL
);
3641 ssh
->packet_dispatch
[qh
->msg2
] = ssh_queueing_handler
;
3644 ssh
->qtail
->next
= qh
;
3649 static void ssh_rportfwd_succfail(Ssh ssh
, struct Packet
*pktin
, void *ctx
)
3651 struct ssh_rportfwd
*rpf
, *pf
= (struct ssh_rportfwd
*)ctx
;
3653 if (pktin
->type
== (ssh
->version
== 1 ? SSH1_SMSG_SUCCESS
:
3654 SSH2_MSG_REQUEST_SUCCESS
)) {
3655 logeventf(ssh
, "Remote port forwarding from %s enabled",
3658 logeventf(ssh
, "Remote port forwarding from %s refused",
3661 rpf
= del234(ssh
->rportfwds
, pf
);
3667 static void ssh_setup_portfwd(Ssh ssh
, const Config
*cfg
)
3671 int sport
,dport
,sserv
,dserv
;
3672 char sports
[256], dports
[256], saddr
[256], host
[256];
3673 const char *portfwd_strptr
;
3675 portfwd_strptr
= cfg
->portfwd
;
3677 if (!ssh
->portfwds
) {
3678 ssh
->portfwds
= newtree234(ssh_portcmp
);
3681 * Go through the existing port forwardings and tag them
3682 * with keep==FALSE. Any that we want to keep will be
3683 * re-enabled as we go through the configuration and find
3684 * out which bits are the same as they were before.
3686 struct ssh_portfwd
*epf
;
3688 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3692 while (*portfwd_strptr
) {
3693 type
= *portfwd_strptr
++;
3696 while (*portfwd_strptr
&& *portfwd_strptr
!= '\t') {
3697 if (*portfwd_strptr
== ':') {
3699 * We've seen a colon in the middle of the
3700 * source port number. This means that
3701 * everything we've seen until now is the
3702 * source _address_, so we'll move it into
3703 * saddr and start sports from the beginning
3708 if (ssh
->version
== 1 && type
== 'R') {
3709 logeventf(ssh
, "SSH1 cannot handle remote source address "
3710 "spec \"%s\"; ignoring", sports
);
3712 strcpy(saddr
, sports
);
3715 if (n
< 255) sports
[n
++] = *portfwd_strptr
++;
3719 if (*portfwd_strptr
== '\t')
3722 while (*portfwd_strptr
&& *portfwd_strptr
!= ':') {
3723 if (n
< 255) host
[n
++] = *portfwd_strptr
++;
3726 if (*portfwd_strptr
== ':')
3729 while (*portfwd_strptr
) {
3730 if (n
< 255) dports
[n
++] = *portfwd_strptr
++;
3734 dport
= atoi(dports
);
3738 dport
= net_service_lookup(dports
);
3740 logeventf(ssh
, "Service lookup failed for destination"
3741 " port \"%s\"", dports
);
3745 while (*portfwd_strptr
) portfwd_strptr
++;
3747 portfwd_strptr
++; /* eat the NUL and move to next one */
3749 sport
= atoi(sports
);
3753 sport
= net_service_lookup(sports
);
3755 logeventf(ssh
, "Service lookup failed for source"
3756 " port \"%s\"", sports
);
3759 if (sport
&& dport
) {
3760 /* Set up a description of the source port. */
3761 struct ssh_portfwd
*pfrec
, *epfrec
;
3763 sportdesc
= dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
3764 (int)(*saddr?
strlen(saddr
):0), *saddr?saddr
:NULL
,
3765 (int)(*saddr?
1:0), ":",
3766 (int)(sserv ?
strlen(sports
) : 0), sports
,
3767 sserv
, "(", sport
, sserv
, ")");
3769 pfrec
= snew(struct ssh_portfwd
);
3771 pfrec
->saddr
= *saddr ?
dupstr(saddr
) : NULL
;
3772 pfrec
->sport
= sport
;
3773 pfrec
->daddr
= dupstr(host
);
3774 pfrec
->dport
= dport
;
3775 pfrec
->local
= NULL
;
3776 pfrec
->remote
= NULL
;
3778 epfrec
= add234(ssh
->portfwds
, pfrec
);
3779 if (epfrec
!= pfrec
) {
3781 * We already have a port forwarding with precisely
3782 * these parameters. Hence, no need to do anything;
3783 * simply tag the existing one as `keep'.
3785 epfrec
->keep
= TRUE
;
3786 free_portfwd(pfrec
);
3787 } else if (type
== 'L') {
3788 /* Verbose description of the destination port */
3789 char *dportdesc
= dupprintf("%s:%.*s%.*s%d%.*s",
3791 (int)(dserv ?
strlen(dports
) : 0), dports
,
3792 dserv
, "(", dport
, dserv
, ")");
3793 const char *err
= pfd_addforward(host
, dport
,
3794 *saddr ? saddr
: NULL
,
3795 sport
, ssh
, &ssh
->cfg
,
3798 logeventf(ssh
, "Local port %s forward to %s"
3799 " failed: %s", sportdesc
, dportdesc
, err
);
3801 logeventf(ssh
, "Local port %s forwarding to %s",
3802 sportdesc
, dportdesc
);
3805 } else if (type
== 'D') {
3806 const char *err
= pfd_addforward(NULL
, -1,
3807 *saddr ? saddr
: NULL
,
3808 sport
, ssh
, &ssh
->cfg
,
3811 logeventf(ssh
, "Local port %s SOCKS dynamic forward"
3812 " setup failed: %s", sportdesc
, err
);
3814 logeventf(ssh
, "Local port %s doing SOCKS"
3815 " dynamic forwarding", sportdesc
);
3818 struct ssh_rportfwd
*pf
;
3821 * Ensure the remote port forwardings tree exists.
3823 if (!ssh
->rportfwds
) {
3824 if (ssh
->version
== 1)
3825 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3827 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
3830 pf
= snew(struct ssh_rportfwd
);
3831 strcpy(pf
->dhost
, host
);
3834 if (add234(ssh
->rportfwds
, pf
) != pf
) {
3835 logeventf(ssh
, "Duplicate remote port forwarding to %s:%d",
3839 logeventf(ssh
, "Requesting remote port %s"
3840 " forward to %s:%.*s%.*s%d%.*s",
3842 (int)(dserv ?
strlen(dports
) : 0), dports
,
3843 dserv
, "(", dport
, dserv
, ")");
3845 pf
->sportdesc
= sportdesc
;
3850 if (ssh
->version
== 1) {
3851 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
3856 ssh_queue_handler(ssh
, SSH1_SMSG_SUCCESS
,
3858 ssh_rportfwd_succfail
, pf
);
3860 struct Packet
*pktout
;
3861 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
3862 ssh2_pkt_addstring(pktout
, "tcpip-forward");
3863 ssh2_pkt_addbool(pktout
, 1);/* want reply */
3865 ssh2_pkt_addstring(pktout
, saddr
);
3866 } else if (ssh
->cfg
.rport_acceptall
) {
3867 ssh2_pkt_addstring(pktout
, "0.0.0.0");
3869 ssh2_pkt_addstring(pktout
, "127.0.0.1");
3871 ssh2_pkt_adduint32(pktout
, sport
);
3872 ssh2_pkt_send(ssh
, pktout
);
3874 ssh_queue_handler(ssh
, SSH2_MSG_REQUEST_SUCCESS
,
3875 SSH2_MSG_REQUEST_FAILURE
,
3876 ssh_rportfwd_succfail
, pf
);
3885 * Now go through and destroy any port forwardings which were
3889 struct ssh_portfwd
*epf
;
3891 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3895 message
= dupprintf("%s port forwarding from %s%s%d",
3896 epf
->type
== 'L' ?
"local" :
3897 epf
->type
== 'R' ?
"remote" : "dynamic",
3898 epf
->saddr ? epf
->saddr
: "",
3899 epf
->saddr ?
":" : "",
3902 if (epf
->type
!= 'D') {
3903 char *msg2
= dupprintf("%s to %s:%d", message
,
3904 epf
->daddr
, epf
->dport
);
3909 logeventf(ssh
, "Cancelling %s", message
);
3913 struct ssh_rportfwd
*rpf
= epf
->remote
;
3914 struct Packet
*pktout
;
3917 * Cancel the port forwarding at the server
3920 if (ssh
->version
== 1) {
3922 * We cannot cancel listening ports on the
3923 * server side in SSH1! There's no message
3924 * to support it. Instead, we simply remove
3925 * the rportfwd record from the local end
3926 * so that any connections the server tries
3927 * to make on it are rejected.
3930 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
3931 ssh2_pkt_addstring(pktout
, "cancel-tcpip-forward");
3932 ssh2_pkt_addbool(pktout
, 0);/* _don't_ want reply */
3934 ssh2_pkt_addstring(pktout
, epf
->saddr
);
3935 } else if (ssh
->cfg
.rport_acceptall
) {
3936 ssh2_pkt_addstring(pktout
, "0.0.0.0");
3938 ssh2_pkt_addstring(pktout
, "127.0.0.1");
3940 ssh2_pkt_adduint32(pktout
, epf
->sport
);
3941 ssh2_pkt_send(ssh
, pktout
);
3944 del234(ssh
->rportfwds
, rpf
);
3946 } else if (epf
->local
) {
3947 pfd_terminate(epf
->local
);
3950 delpos234(ssh
->portfwds
, i
);
3952 i
--; /* so we don't skip one in the list */
3957 static void ssh1_smsg_stdout_stderr_data(Ssh ssh
, struct Packet
*pktin
)
3960 int stringlen
, bufsize
;
3962 ssh_pkt_getstring(pktin
, &string
, &stringlen
);
3963 if (string
== NULL
) {
3964 bombout(("Incoming terminal data packet was badly formed"));
3968 bufsize
= from_backend(ssh
->frontend
, pktin
->type
== SSH1_SMSG_STDERR_DATA
,
3970 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3971 ssh
->v1_stdout_throttling
= 1;
3972 ssh1_throttle(ssh
, +1);
3976 static void ssh1_smsg_x11_open(Ssh ssh
, struct Packet
*pktin
)
3978 /* Remote side is trying to open a channel to talk to our
3979 * X-Server. Give them back a local channel number. */
3980 struct ssh_channel
*c
;
3981 int remoteid
= ssh_pkt_getuint32(pktin
);
3983 logevent("Received X11 connect request");
3984 /* Refuse if X11 forwarding is disabled. */
3985 if (!ssh
->X11_fwd_enabled
) {
3986 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3987 PKT_INT
, remoteid
, PKT_END
);
3988 logevent("Rejected X11 connect request");
3990 c
= snew(struct ssh_channel
);
3993 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
3994 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
3995 logevent("Opening X11 forward connection failed");
3997 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3998 PKT_INT
, remoteid
, PKT_END
);
4001 ("Opening X11 forward connection succeeded");
4002 c
->remoteid
= remoteid
;
4003 c
->localid
= alloc_channel_id(ssh
);
4005 c
->v
.v1
.throttling
= 0;
4006 c
->type
= CHAN_X11
; /* identify channel type */
4007 add234(ssh
->channels
, c
);
4008 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4009 PKT_INT
, c
->remoteid
, PKT_INT
,
4010 c
->localid
, PKT_END
);
4011 logevent("Opened X11 forward channel");
4016 static void ssh1_smsg_agent_open(Ssh ssh
, struct Packet
*pktin
)
4018 /* Remote side is trying to open a channel to talk to our
4019 * agent. Give them back a local channel number. */
4020 struct ssh_channel
*c
;
4021 int remoteid
= ssh_pkt_getuint32(pktin
);
4023 /* Refuse if agent forwarding is disabled. */
4024 if (!ssh
->agentfwd_enabled
) {
4025 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4026 PKT_INT
, remoteid
, PKT_END
);
4028 c
= snew(struct ssh_channel
);
4030 c
->remoteid
= remoteid
;
4031 c
->localid
= alloc_channel_id(ssh
);
4033 c
->v
.v1
.throttling
= 0;
4034 c
->type
= CHAN_AGENT
; /* identify channel type */
4035 c
->u
.a
.lensofar
= 0;
4036 add234(ssh
->channels
, c
);
4037 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4038 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
4043 static void ssh1_msg_port_open(Ssh ssh
, struct Packet
*pktin
)
4045 /* Remote side is trying to open a channel to talk to a
4046 * forwarded port. Give them back a local channel number. */
4047 struct ssh_channel
*c
;
4048 struct ssh_rportfwd pf
;
4051 char *host
, buf
[1024];
4053 c
= snew(struct ssh_channel
);
4056 remoteid
= ssh_pkt_getuint32(pktin
);
4057 ssh_pkt_getstring(pktin
, &host
, &hostsize
);
4058 port
= ssh_pkt_getuint32(pktin
);
4060 if (hostsize
>= lenof(pf
.dhost
))
4061 hostsize
= lenof(pf
.dhost
)-1;
4062 memcpy(pf
.dhost
, host
, hostsize
);
4063 pf
.dhost
[hostsize
] = '\0';
4066 if (find234(ssh
->rportfwds
, &pf
, NULL
) == NULL
) {
4067 sprintf(buf
, "Rejected remote port open request for %s:%d",
4070 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4071 PKT_INT
, remoteid
, PKT_END
);
4073 sprintf(buf
, "Received remote port open request for %s:%d",
4076 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
4080 sprintf(buf
, "Port open failed: %s", e
);
4083 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4084 PKT_INT
, remoteid
, PKT_END
);
4086 c
->remoteid
= remoteid
;
4087 c
->localid
= alloc_channel_id(ssh
);
4089 c
->v
.v1
.throttling
= 0;
4090 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
4091 add234(ssh
->channels
, c
);
4092 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4093 PKT_INT
, c
->remoteid
, PKT_INT
,
4094 c
->localid
, PKT_END
);
4095 logevent("Forwarded port opened successfully");
4100 static void ssh1_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
4102 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4103 unsigned int localid
= ssh_pkt_getuint32(pktin
);
4104 struct ssh_channel
*c
;
4106 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4107 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4108 c
->remoteid
= localid
;
4109 c
->type
= CHAN_SOCKDATA
;
4110 c
->v
.v1
.throttling
= 0;
4111 pfd_confirm(c
->u
.pfd
.s
);
4114 if (c
&& c
->closes
) {
4116 * We have a pending close on this channel,
4117 * which we decided on before the server acked
4118 * the channel open. So now we know the
4119 * remoteid, we can close it again.
4121 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
4122 PKT_INT
, c
->remoteid
, PKT_END
);
4126 static void ssh1_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
4128 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4129 struct ssh_channel
*c
;
4131 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4132 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4133 logevent("Forwarded connection refused by server");
4134 pfd_close(c
->u
.pfd
.s
);
4135 del234(ssh
->channels
, c
);
4140 static void ssh1_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
4142 /* Remote side closes a channel. */
4143 unsigned i
= ssh_pkt_getuint32(pktin
);
4144 struct ssh_channel
*c
;
4145 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4146 if (c
&& ((int)c
->remoteid
) != -1) {
4149 (pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
4151 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
4152 logevent("Forwarded X11 connection terminated");
4153 assert(c
->u
.x11
.s
!= NULL
);
4154 x11_close(c
->u
.x11
.s
);
4157 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
4158 logevent("Forwarded port closed");
4159 assert(c
->u
.pfd
.s
!= NULL
);
4160 pfd_close(c
->u
.pfd
.s
);
4164 c
->closes
|= (closetype
<< 2); /* seen this message */
4165 if (!(c
->closes
& closetype
)) {
4166 send_packet(ssh
, pktin
->type
, PKT_INT
, c
->remoteid
,
4168 c
->closes
|= closetype
; /* sent it too */
4171 if (c
->closes
== 15) {
4172 del234(ssh
->channels
, c
);
4176 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4177 pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
4178 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
4183 static void ssh1_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
4185 /* Data sent down one of our channels. */
4186 int i
= ssh_pkt_getuint32(pktin
);
4189 struct ssh_channel
*c
;
4191 ssh_pkt_getstring(pktin
, &p
, &len
);
4193 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4198 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
4201 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
4204 /* Data for an agent message. Buffer it. */
4206 if (c
->u
.a
.lensofar
< 4) {
4207 unsigned int l
= min(4 - c
->u
.a
.lensofar
, len
);
4208 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
4212 c
->u
.a
.lensofar
+= l
;
4214 if (c
->u
.a
.lensofar
== 4) {
4216 4 + GET_32BIT(c
->u
.a
.msglen
);
4217 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
4219 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
4221 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
4223 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
4225 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
4229 c
->u
.a
.lensofar
+= l
;
4231 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
4234 if (agent_query(c
->u
.a
.message
,
4237 ssh_agentf_callback
, c
))
4238 ssh_agentf_callback(c
, reply
, replylen
);
4239 sfree(c
->u
.a
.message
);
4240 c
->u
.a
.lensofar
= 0;
4243 bufsize
= 0; /* agent channels never back up */
4246 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4247 c
->v
.v1
.throttling
= 1;
4248 ssh1_throttle(ssh
, +1);
4253 static void ssh1_smsg_exit_status(Ssh ssh
, struct Packet
*pktin
)
4256 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
4257 sprintf(buf
, "Server sent command exit status %d",
4260 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
4262 * In case `helpful' firewalls or proxies tack
4263 * extra human-readable text on the end of the
4264 * session which we might mistake for another
4265 * encrypted packet, we close the session once
4266 * we've sent EXIT_CONFIRMATION.
4268 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4271 static void do_ssh1_connection(Ssh ssh
, unsigned char *in
, int inlen
,
4272 struct Packet
*pktin
)
4274 crBegin(ssh
->do_ssh1_connection_crstate
);
4276 ssh
->packet_dispatch
[SSH1_SMSG_STDOUT_DATA
] =
4277 ssh
->packet_dispatch
[SSH1_SMSG_STDERR_DATA
] =
4278 ssh1_smsg_stdout_stderr_data
;
4280 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
] =
4281 ssh1_msg_channel_open_confirmation
;
4282 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_FAILURE
] =
4283 ssh1_msg_channel_open_failure
;
4284 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE
] =
4285 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
] =
4286 ssh1_msg_channel_close
;
4287 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_DATA
] = ssh1_msg_channel_data
;
4288 ssh
->packet_dispatch
[SSH1_SMSG_EXIT_STATUS
] = ssh1_smsg_exit_status
;
4290 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
4291 logevent("Requesting agent forwarding");
4292 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
4296 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4297 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4298 bombout(("Protocol confusion"));
4300 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4301 logevent("Agent forwarding refused");
4303 logevent("Agent forwarding enabled");
4304 ssh
->agentfwd_enabled
= TRUE
;
4305 ssh
->packet_dispatch
[SSH1_SMSG_AGENT_OPEN
] = ssh1_smsg_agent_open
;
4309 if (ssh
->cfg
.x11_forward
) {
4310 char proto
[20], data
[64];
4311 logevent("Requesting X11 forwarding");
4312 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
4313 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
4314 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
4315 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
4316 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4317 PKT_STR
, proto
, PKT_STR
, data
,
4318 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
4321 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4322 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
4327 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4328 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4329 bombout(("Protocol confusion"));
4331 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4332 logevent("X11 forwarding refused");
4334 logevent("X11 forwarding enabled");
4335 ssh
->X11_fwd_enabled
= TRUE
;
4336 ssh
->packet_dispatch
[SSH1_SMSG_X11_OPEN
] = ssh1_smsg_x11_open
;
4340 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
4341 ssh
->packet_dispatch
[SSH1_MSG_PORT_OPEN
] = ssh1_msg_port_open
;
4343 if (!ssh
->cfg
.nopty
) {
4344 /* Unpick the terminal-speed string. */
4345 /* XXX perhaps we should allow no speeds to be sent. */
4346 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
4347 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
4348 /* Send the pty request. */
4349 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
4350 PKT_STR
, ssh
->cfg
.termtype
,
4351 PKT_INT
, ssh
->term_height
,
4352 PKT_INT
, ssh
->term_width
,
4353 PKT_INT
, 0, PKT_INT
, 0, /* width,height in pixels */
4354 PKT_CHAR
, 192, PKT_INT
, ssh
->ispeed
, /* TTY_OP_ISPEED */
4355 PKT_CHAR
, 193, PKT_INT
, ssh
->ospeed
, /* TTY_OP_OSPEED */
4356 PKT_CHAR
, 0, PKT_END
);
4357 ssh
->state
= SSH_STATE_INTERMED
;
4361 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4362 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4363 bombout(("Protocol confusion"));
4365 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4366 c_write_str(ssh
, "Server refused to allocate pty\r\n");
4367 ssh
->editing
= ssh
->echoing
= 1;
4369 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
4370 ssh
->ospeed
, ssh
->ispeed
);
4372 ssh
->editing
= ssh
->echoing
= 1;
4375 if (ssh
->cfg
.compression
) {
4376 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
4380 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4381 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4382 bombout(("Protocol confusion"));
4384 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4385 c_write_str(ssh
, "Server refused to compress\r\n");
4387 logevent("Started compression");
4388 ssh
->v1_compressing
= TRUE
;
4389 ssh
->cs_comp_ctx
= zlib_compress_init();
4390 logevent("Initialised zlib (RFC1950) compression");
4391 ssh
->sc_comp_ctx
= zlib_decompress_init();
4392 logevent("Initialised zlib (RFC1950) decompression");
4396 * Start the shell or command.
4398 * Special case: if the first-choice command is an SSH2
4399 * subsystem (hence not usable here) and the second choice
4400 * exists, we fall straight back to that.
4403 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
4405 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
4406 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
4407 ssh
->fallback_cmd
= TRUE
;
4410 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
4412 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
4413 logevent("Started session");
4416 ssh
->state
= SSH_STATE_SESSION
;
4417 if (ssh
->size_needed
)
4418 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
4419 if (ssh
->eof_needed
)
4420 ssh_special(ssh
, TS_EOF
);
4423 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
4425 ssh
->channels
= newtree234(ssh_channelcmp
);
4429 * By this point, most incoming packets are already being
4430 * handled by the dispatch table, and we need only pay
4431 * attention to the unusual ones.
4436 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
4437 /* may be from EXEC_SHELL on some servers */
4438 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4439 /* may be from EXEC_SHELL on some servers
4440 * if no pty is available or in other odd cases. Ignore */
4442 bombout(("Strange packet received: type %d", pktin
->type
));
4447 int len
= min(inlen
, 512);
4448 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4449 PKT_INT
, len
, PKT_DATA
, in
, len
,
4450 PKTT_OTHER
, PKT_END
);
4461 * Handle the top-level SSH2 protocol.
4463 static void ssh1_msg_debug(Ssh ssh
, struct Packet
*pktin
)
4468 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4469 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
4474 static void ssh1_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
4476 /* log reason code in disconnect message */
4480 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4481 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen
, msg
));
4484 void ssh_msg_ignore(Ssh ssh
, struct Packet
*pktin
)
4486 /* Do nothing, because we're ignoring it! Duhh. */
4489 static void ssh1_protocol_setup(Ssh ssh
)
4494 * Most messages are handled by the coroutines.
4496 for (i
= 0; i
< 256; i
++)
4497 ssh
->packet_dispatch
[i
] = NULL
;
4500 * These special message types we install handlers for.
4502 ssh
->packet_dispatch
[SSH1_MSG_DISCONNECT
] = ssh1_msg_disconnect
;
4503 ssh
->packet_dispatch
[SSH1_MSG_IGNORE
] = ssh_msg_ignore
;
4504 ssh
->packet_dispatch
[SSH1_MSG_DEBUG
] = ssh1_msg_debug
;
4507 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
4508 struct Packet
*pktin
)
4510 if (ssh
->state
== SSH_STATE_CLOSED
)
4513 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
4514 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
4518 if (!ssh
->protocol_initial_phase_done
) {
4519 if (do_ssh1_login(ssh
, in
, inlen
, pktin
))
4520 ssh
->protocol_initial_phase_done
= TRUE
;
4525 do_ssh1_connection(ssh
, in
, inlen
, pktin
);
4529 * Utility routine for decoding comma-separated strings in KEXINIT.
4531 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
4534 if (!needle
|| !haystack
) /* protect against null pointers */
4536 needlen
= strlen(needle
);
4539 * Is it at the start of the string?
4541 if (haylen
>= needlen
&& /* haystack is long enough */
4542 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4543 (haylen
== needlen
|| haystack
[needlen
] == ',')
4544 /* either , or EOS follows */
4548 * If not, search for the next comma and resume after that.
4549 * If no comma found, terminate.
4551 while (haylen
> 0 && *haystack
!= ',')
4552 haylen
--, haystack
++;
4555 haylen
--, haystack
++; /* skip over comma itself */
4560 * SSH2 key creation method.
4562 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
4563 unsigned char *sessid
, char chr
,
4564 unsigned char *keyspace
)
4567 /* First 20 bytes. */
4569 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4571 SHA_Bytes(&s
, H
, 20);
4572 SHA_Bytes(&s
, &chr
, 1);
4573 SHA_Bytes(&s
, sessid
, 20);
4574 SHA_Final(&s
, keyspace
);
4575 /* Next 20 bytes. */
4577 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4579 SHA_Bytes(&s
, H
, 20);
4580 SHA_Bytes(&s
, keyspace
, 20);
4581 SHA_Final(&s
, keyspace
+ 20);
4585 * Handle the SSH2 transport layer.
4587 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
,
4588 struct Packet
*pktin
)
4590 struct do_ssh2_transport_state
{
4591 int nbits
, pbits
, warn
;
4592 Bignum p
, g
, e
, f
, K
;
4593 int kex_init_value
, kex_reply_value
;
4594 const struct ssh_mac
**maclist
;
4596 const struct ssh2_cipher
*cscipher_tobe
;
4597 const struct ssh2_cipher
*sccipher_tobe
;
4598 const struct ssh_mac
*csmac_tobe
;
4599 const struct ssh_mac
*scmac_tobe
;
4600 const struct ssh_compress
*cscomp_tobe
;
4601 const struct ssh_compress
*sccomp_tobe
;
4602 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4603 int hostkeylen
, siglen
;
4604 void *hkey
; /* actual host key */
4605 unsigned char exchange_hash
[20];
4606 int n_preferred_kex
;
4607 const struct ssh_kex
*preferred_kex
[KEX_MAX
];
4608 int n_preferred_ciphers
;
4609 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
4610 const struct ssh_compress
*preferred_comp
;
4612 struct Packet
*pktout
;
4614 crState(do_ssh2_transport_state
);
4616 crBegin(ssh
->do_ssh2_transport_crstate
);
4618 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
4619 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
4620 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
4627 * Set up the preferred key exchange. (NULL => warn below here)
4629 s
->n_preferred_kex
= 0;
4630 for (i
= 0; i
< KEX_MAX
; i
++) {
4631 switch (ssh
->cfg
.ssh_kexlist
[i
]) {
4633 s
->preferred_kex
[s
->n_preferred_kex
++] =
4634 &ssh_diffiehellman_gex
;
4637 s
->preferred_kex
[s
->n_preferred_kex
++] =
4638 &ssh_diffiehellman_group14
;
4641 s
->preferred_kex
[s
->n_preferred_kex
++] =
4642 &ssh_diffiehellman_group1
;
4645 /* Flag for later. Don't bother if it's the last in
4647 if (i
< KEX_MAX
- 1) {
4648 s
->preferred_kex
[s
->n_preferred_kex
++] = NULL
;
4658 * Set up the preferred ciphers. (NULL => warn below here)
4660 s
->n_preferred_ciphers
= 0;
4661 for (i
= 0; i
< CIPHER_MAX
; i
++) {
4662 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
4663 case CIPHER_BLOWFISH
:
4664 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
4667 if (ssh
->cfg
.ssh2_des_cbc
) {
4668 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
4672 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
4675 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
4678 /* Flag for later. Don't bother if it's the last in
4680 if (i
< CIPHER_MAX
- 1) {
4681 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
4689 * Set up preferred compression.
4691 if (ssh
->cfg
.compression
)
4692 s
->preferred_comp
= &ssh_zlib
;
4694 s
->preferred_comp
= &ssh_comp_none
;
4697 * Be prepared to work around the buggy MAC problem.
4699 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
4700 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
4702 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
4706 int i
, j
, commalist_started
;
4709 * Enable queueing of outgoing auth- or connection-layer
4710 * packets while we are in the middle of a key exchange.
4712 ssh
->queueing
= TRUE
;
4715 * Flag that KEX is in progress.
4717 ssh
->kex_in_progress
= TRUE
;
4720 * Construct and send our key exchange packet.
4722 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEXINIT
);
4723 for (i
= 0; i
< 16; i
++)
4724 ssh2_pkt_addbyte(s
->pktout
, (unsigned char) random_byte());
4725 /* List key exchange algorithms. */
4726 ssh2_pkt_addstring_start(s
->pktout
);
4727 commalist_started
= 0;
4728 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4729 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4730 if (!k
) continue; /* warning flag */
4731 if (commalist_started
)
4732 ssh2_pkt_addstring_str(s
->pktout
, ",");
4733 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_kex
[i
]->name
);
4734 commalist_started
= 1;
4736 /* List server host key algorithms. */
4737 ssh2_pkt_addstring_start(s
->pktout
);
4738 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4739 ssh2_pkt_addstring_str(s
->pktout
, hostkey_algs
[i
]->name
);
4740 if (i
< lenof(hostkey_algs
) - 1)
4741 ssh2_pkt_addstring_str(s
->pktout
, ",");
4743 /* List client->server encryption algorithms. */
4744 ssh2_pkt_addstring_start(s
->pktout
);
4745 commalist_started
= 0;
4746 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4747 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4748 if (!c
) continue; /* warning flag */
4749 for (j
= 0; j
< c
->nciphers
; j
++) {
4750 if (commalist_started
)
4751 ssh2_pkt_addstring_str(s
->pktout
, ",");
4752 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4753 commalist_started
= 1;
4756 /* List server->client encryption algorithms. */
4757 ssh2_pkt_addstring_start(s
->pktout
);
4758 commalist_started
= 0;
4759 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4760 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4761 if (!c
) continue; /* warning flag */
4762 for (j
= 0; j
< c
->nciphers
; j
++) {
4763 if (commalist_started
)
4764 ssh2_pkt_addstring_str(s
->pktout
, ",");
4765 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4766 commalist_started
= 1;
4769 /* List client->server MAC algorithms. */
4770 ssh2_pkt_addstring_start(s
->pktout
);
4771 for (i
= 0; i
< s
->nmacs
; i
++) {
4772 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4773 if (i
< s
->nmacs
- 1)
4774 ssh2_pkt_addstring_str(s
->pktout
, ",");
4776 /* List server->client MAC algorithms. */
4777 ssh2_pkt_addstring_start(s
->pktout
);
4778 for (i
= 0; i
< s
->nmacs
; i
++) {
4779 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4780 if (i
< s
->nmacs
- 1)
4781 ssh2_pkt_addstring_str(s
->pktout
, ",");
4783 /* List client->server compression algorithms. */
4784 ssh2_pkt_addstring_start(s
->pktout
);
4785 assert(lenof(compressions
) > 1);
4786 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4787 for (i
= 0; i
< lenof(compressions
); i
++) {
4788 const struct ssh_compress
*c
= compressions
[i
];
4789 if (c
!= s
->preferred_comp
) {
4790 ssh2_pkt_addstring_str(s
->pktout
, ",");
4791 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4794 /* List server->client compression algorithms. */
4795 ssh2_pkt_addstring_start(s
->pktout
);
4796 assert(lenof(compressions
) > 1);
4797 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4798 for (i
= 0; i
< lenof(compressions
); i
++) {
4799 const struct ssh_compress
*c
= compressions
[i
];
4800 if (c
!= s
->preferred_comp
) {
4801 ssh2_pkt_addstring_str(s
->pktout
, ",");
4802 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4805 /* List client->server languages. Empty list. */
4806 ssh2_pkt_addstring_start(s
->pktout
);
4807 /* List server->client languages. Empty list. */
4808 ssh2_pkt_addstring_start(s
->pktout
);
4809 /* First KEX packet does _not_ follow, because we're not that brave. */
4810 ssh2_pkt_addbool(s
->pktout
, FALSE
);
4812 ssh2_pkt_adduint32(s
->pktout
, 0);
4815 ssh
->exhash
= ssh
->exhashbase
;
4816 sha_string(&ssh
->exhash
, s
->pktout
->data
+ 5, s
->pktout
->length
- 5);
4818 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
4822 if (pktin
->length
> 5)
4823 sha_string(&ssh
->exhash
, pktin
->data
+ 5, pktin
->length
- 5);
4826 * Now examine the other side's KEXINIT to see what we're up
4833 if (pktin
->type
!= SSH2_MSG_KEXINIT
) {
4834 bombout(("expected key exchange packet from server"));
4838 ssh
->hostkey
= NULL
;
4839 s
->cscipher_tobe
= NULL
;
4840 s
->sccipher_tobe
= NULL
;
4841 s
->csmac_tobe
= NULL
;
4842 s
->scmac_tobe
= NULL
;
4843 s
->cscomp_tobe
= NULL
;
4844 s
->sccomp_tobe
= NULL
;
4845 pktin
->savedpos
+= 16; /* skip garbage cookie */
4846 ssh_pkt_getstring(pktin
, &str
, &len
); /* key exchange algorithms */
4848 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4849 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4852 } else if (in_commasep_string(k
->name
, str
, len
)) {
4857 askalg(ssh
->frontend
, "key-exchange algorithm",
4863 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
4864 str ? str
: "(null)"));
4867 ssh_pkt_getstring(pktin
, &str
, &len
); /* host key algorithms */
4868 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4869 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
4870 ssh
->hostkey
= hostkey_algs
[i
];
4874 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server cipher */
4876 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4877 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4881 for (j
= 0; j
< c
->nciphers
; j
++) {
4882 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4883 s
->cscipher_tobe
= c
->list
[j
];
4888 if (s
->cscipher_tobe
) {
4890 askalg(ssh
->frontend
, "client-to-server cipher",
4891 s
->cscipher_tobe
->name
);
4895 if (!s
->cscipher_tobe
) {
4896 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
4897 str ? str
: "(null)"));
4901 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client cipher */
4903 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4904 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4908 for (j
= 0; j
< c
->nciphers
; j
++) {
4909 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4910 s
->sccipher_tobe
= c
->list
[j
];
4915 if (s
->sccipher_tobe
) {
4917 askalg(ssh
->frontend
, "server-to-client cipher",
4918 s
->sccipher_tobe
->name
);
4922 if (!s
->sccipher_tobe
) {
4923 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
4924 str ? str
: "(null)"));
4928 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server mac */
4929 for (i
= 0; i
< s
->nmacs
; i
++) {
4930 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4931 s
->csmac_tobe
= s
->maclist
[i
];
4935 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client mac */
4936 for (i
= 0; i
< s
->nmacs
; i
++) {
4937 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4938 s
->scmac_tobe
= s
->maclist
[i
];
4942 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server compression */
4943 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4944 const struct ssh_compress
*c
=
4945 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4946 if (in_commasep_string(c
->name
, str
, len
)) {
4951 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client compression */
4952 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4953 const struct ssh_compress
*c
=
4954 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4955 if (in_commasep_string(c
->name
, str
, len
)) {
4963 * Work out the number of bits of key we will need from the key
4964 * exchange. We start with the maximum key length of either
4970 csbits
= s
->cscipher_tobe
->keylen
;
4971 scbits
= s
->sccipher_tobe
->keylen
;
4972 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
4974 /* The keys only have 160-bit entropy, since they're based on
4975 * a SHA-1 hash. So cap the key size at 160 bits. */
4980 * If we're doing Diffie-Hellman group exchange, start by
4981 * requesting a group.
4983 if (!ssh
->kex
->pdata
) {
4984 logevent("Doing Diffie-Hellman group exchange");
4985 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
4987 * Work out how big a DH group we will need to allow that
4990 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
4991 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
4992 ssh2_pkt_adduint32(s
->pktout
, s
->pbits
);
4993 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
4996 if (pktin
->type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
4997 bombout(("expected key exchange group packet from server"));
5000 s
->p
= ssh2_pkt_getmp(pktin
);
5001 s
->g
= ssh2_pkt_getmp(pktin
);
5002 if (!s
->p
|| !s
->g
) {
5003 bombout(("unable to read mp-ints from incoming group packet"));
5006 ssh
->kex_ctx
= dh_setup_gex(s
->p
, s
->g
);
5007 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
5008 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
5010 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP
;
5011 ssh
->kex_ctx
= dh_setup_group(ssh
->kex
);
5012 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
5013 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
5014 logeventf(ssh
, "Using Diffie-Hellman with standard group \"%s\"",
5015 ssh
->kex
->groupname
);
5018 logevent("Doing Diffie-Hellman key exchange");
5020 * Now generate and send e for Diffie-Hellman.
5022 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
5023 s
->pktout
= ssh2_pkt_init(s
->kex_init_value
);
5024 ssh2_pkt_addmp(s
->pktout
, s
->e
);
5025 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5028 if (pktin
->type
!= s
->kex_reply_value
) {
5029 bombout(("expected key exchange reply packet from server"));
5032 ssh_pkt_getstring(pktin
, &s
->hostkeydata
, &s
->hostkeylen
);
5033 s
->f
= ssh2_pkt_getmp(pktin
);
5035 bombout(("unable to parse key exchange reply packet"));
5038 ssh_pkt_getstring(pktin
, &s
->sigdata
, &s
->siglen
);
5040 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
5042 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
5043 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5044 sha_uint32(&ssh
->exhash
, s
->pbits
);
5045 sha_mpint(&ssh
->exhash
, s
->p
);
5046 sha_mpint(&ssh
->exhash
, s
->g
);
5048 sha_mpint(&ssh
->exhash
, s
->e
);
5049 sha_mpint(&ssh
->exhash
, s
->f
);
5050 sha_mpint(&ssh
->exhash
, s
->K
);
5051 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
5053 dh_cleanup(ssh
->kex_ctx
);
5054 ssh
->kex_ctx
= NULL
;
5057 debug(("Exchange hash is:\n"));
5058 dmemdump(s
->exchange_hash
, 20);
5061 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
5063 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
5064 (char *)s
->exchange_hash
, 20)) {
5065 bombout(("Server's host key did not match the signature supplied"));
5070 * Authenticate remote host: verify host key. (We've already
5071 * checked the signature of the exchange hash.)
5073 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
5074 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
5075 verify_ssh_host_key(ssh
->frontend
,
5076 ssh
->savedhost
, ssh
->savedport
, ssh
->hostkey
->keytype
,
5077 s
->keystr
, s
->fingerprint
);
5078 if (s
->first_kex
) { /* don't bother logging this in rekeys */
5079 logevent("Host key fingerprint is:");
5080 logevent(s
->fingerprint
);
5082 sfree(s
->fingerprint
);
5084 ssh
->hostkey
->freekey(s
->hkey
);
5087 * The exchange hash from the very first key exchange is also
5088 * the session id, used in session key construction and
5092 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
5093 sizeof(s
->exchange_hash
));
5096 * Send SSH2_MSG_NEWKEYS.
5098 s
->pktout
= ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
5099 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5100 ssh
->outgoing_data_size
= 0; /* start counting from here */
5103 * We've sent client NEWKEYS, so create and initialise
5104 * client-to-server session keys.
5106 if (ssh
->cs_cipher_ctx
)
5107 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
5108 ssh
->cscipher
= s
->cscipher_tobe
;
5109 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
5111 if (ssh
->cs_mac_ctx
)
5112 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
5113 ssh
->csmac
= s
->csmac_tobe
;
5114 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
5116 if (ssh
->cs_comp_ctx
)
5117 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
5118 ssh
->cscomp
= s
->cscomp_tobe
;
5119 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
5122 * Set IVs on client-to-server keys. Here we use the exchange
5123 * hash from the _first_ key exchange.
5126 unsigned char keyspace
[40];
5127 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
5128 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
5129 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
5130 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
5131 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
5132 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
5135 logeventf(ssh
, "Initialised %.200s client->server encryption",
5136 ssh
->cscipher
->text_name
);
5137 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
5138 ssh
->csmac
->text_name
);
5139 if (ssh
->cscomp
->text_name
)
5140 logeventf(ssh
, "Initialised %s compression",
5141 ssh
->cscomp
->text_name
);
5144 * Now our end of the key exchange is complete, we can send all
5145 * our queued higher-layer packets.
5147 ssh
->queueing
= FALSE
;
5148 ssh2_pkt_queuesend(ssh
);
5151 * Expect SSH2_MSG_NEWKEYS from server.
5154 if (pktin
->type
!= SSH2_MSG_NEWKEYS
) {
5155 bombout(("expected new-keys packet from server"));
5158 ssh
->incoming_data_size
= 0; /* start counting from here */
5161 * We've seen server NEWKEYS, so create and initialise
5162 * server-to-client session keys.
5164 if (ssh
->sc_cipher_ctx
)
5165 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
5166 ssh
->sccipher
= s
->sccipher_tobe
;
5167 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
5169 if (ssh
->sc_mac_ctx
)
5170 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
5171 ssh
->scmac
= s
->scmac_tobe
;
5172 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
5174 if (ssh
->sc_comp_ctx
)
5175 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
5176 ssh
->sccomp
= s
->sccomp_tobe
;
5177 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
5180 * Set IVs on server-to-client keys. Here we use the exchange
5181 * hash from the _first_ key exchange.
5184 unsigned char keyspace
[40];
5185 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
5186 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
5187 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
5188 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
5189 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
5190 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
5192 logeventf(ssh
, "Initialised %.200s server->client encryption",
5193 ssh
->sccipher
->text_name
);
5194 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
5195 ssh
->scmac
->text_name
);
5196 if (ssh
->sccomp
->text_name
)
5197 logeventf(ssh
, "Initialised %s decompression",
5198 ssh
->sccomp
->text_name
);
5201 * Free key exchange data.
5205 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5211 * Key exchange is over. Schedule a timer for our next rekey.
5213 ssh
->kex_in_progress
= FALSE
;
5214 ssh
->last_rekey
= GETTICKCOUNT();
5215 if (ssh
->cfg
.ssh_rekey_time
!= 0)
5216 ssh
->next_rekey
= schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5220 * If this is the first key exchange phase, we must pass the
5221 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5222 * wants to see it but because it will need time to initialise
5223 * itself before it sees an actual packet. In subsequent key
5224 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5225 * it would only confuse the layer above.
5227 if (!s
->first_kex
) {
5233 * Now we're encrypting. Begin returning 1 to the protocol main
5234 * function so that other things can run on top of the
5235 * transport. If we ever see a KEXINIT, we must go back to the
5238 * We _also_ go back to the start if we see pktin==NULL and
5239 * inlen==-1, because this is a special signal meaning
5240 * `initiate client-driven rekey', and `in' contains a message
5241 * giving the reason for the rekey.
5243 while (!((pktin
&& pktin
->type
== SSH2_MSG_KEXINIT
) ||
5244 (!pktin
&& inlen
== -1))) {
5248 logevent("Server initiated key re-exchange");
5250 logevent((char *)in
);
5252 goto begin_key_exchange
;
5258 * Add data to an SSH2 channel output buffer.
5260 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
5263 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
5267 * Attempt to send data on an SSH2 channel.
5269 static int ssh2_try_send(struct ssh_channel
*c
)
5272 struct Packet
*pktout
;
5274 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
5277 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
5278 if ((unsigned)len
> c
->v
.v2
.remwindow
)
5279 len
= c
->v
.v2
.remwindow
;
5280 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
5281 len
= c
->v
.v2
.remmaxpkt
;
5282 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
5283 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5284 dont_log_data(ssh
, pktout
, PKTLOG_OMIT
);
5285 ssh2_pkt_addstring_start(pktout
);
5286 ssh2_pkt_addstring_data(pktout
, data
, len
);
5287 end_log_omission(ssh
, pktout
);
5288 ssh2_pkt_send(ssh
, pktout
);
5289 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
5290 c
->v
.v2
.remwindow
-= len
;
5294 * After having sent as much data as we can, return the amount
5297 return bufchain_size(&c
->v
.v2
.outbuffer
);
5301 * Potentially enlarge the window on an SSH2 channel.
5303 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
5308 * Never send WINDOW_ADJUST for a channel that the remote side
5309 * already thinks it's closed; there's no point, since it won't
5310 * be sending any more data anyway.
5315 if (newwin
> c
->v
.v2
.locwindow
) {
5316 struct Packet
*pktout
;
5318 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5319 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5320 ssh2_pkt_adduint32(pktout
, newwin
- c
->v
.v2
.locwindow
);
5321 ssh2_pkt_send(ssh
, pktout
);
5322 c
->v
.v2
.locwindow
= newwin
;
5326 static void ssh2_msg_channel_window_adjust(Ssh ssh
, struct Packet
*pktin
)
5328 unsigned i
= ssh_pkt_getuint32(pktin
);
5329 struct ssh_channel
*c
;
5330 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5331 if (c
&& !c
->closes
)
5332 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
5335 static void ssh2_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
5338 unsigned int length
;
5339 unsigned i
= ssh_pkt_getuint32(pktin
);
5340 struct ssh_channel
*c
;
5341 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5343 return; /* nonexistent channel */
5344 if (pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5345 ssh_pkt_getuint32(pktin
) != SSH2_EXTENDED_DATA_STDERR
)
5346 return; /* extended but not stderr */
5347 ssh_pkt_getstring(pktin
, &data
, &length
);
5350 c
->v
.v2
.locwindow
-= length
;
5352 case CHAN_MAINSESSION
:
5354 from_backend(ssh
->frontend
, pktin
->type
==
5355 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5359 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5362 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5365 while (length
> 0) {
5366 if (c
->u
.a
.lensofar
< 4) {
5367 unsigned int l
= min(4 - c
->u
.a
.lensofar
, length
);
5368 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5372 c
->u
.a
.lensofar
+= l
;
5374 if (c
->u
.a
.lensofar
== 4) {
5376 4 + GET_32BIT(c
->u
.a
.msglen
);
5377 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
5379 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5381 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5383 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5385 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5389 c
->u
.a
.lensofar
+= l
;
5391 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5394 if (agent_query(c
->u
.a
.message
,
5397 ssh_agentf_callback
, c
))
5398 ssh_agentf_callback(c
, reply
, replylen
);
5399 sfree(c
->u
.a
.message
);
5400 c
->u
.a
.lensofar
= 0;
5407 * If we are not buffering too much data,
5408 * enlarge the window again at the remote side.
5410 if (bufsize
< OUR_V2_WINSIZE
)
5411 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5415 static void ssh2_msg_channel_eof(Ssh ssh
, struct Packet
*pktin
)
5417 unsigned i
= ssh_pkt_getuint32(pktin
);
5418 struct ssh_channel
*c
;
5420 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5422 return; /* nonexistent channel */
5424 if (c
->type
== CHAN_X11
) {
5426 * Remote EOF on an X11 channel means we should
5427 * wrap up and close the channel ourselves.
5429 x11_close(c
->u
.x11
.s
);
5431 } else if (c
->type
== CHAN_AGENT
) {
5433 } else if (c
->type
== CHAN_SOCKDATA
) {
5434 pfd_close(c
->u
.pfd
.s
);
5439 static void ssh2_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
5441 unsigned i
= ssh_pkt_getuint32(pktin
);
5442 struct ssh_channel
*c
;
5443 struct Packet
*pktout
;
5445 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5446 if (!c
|| ((int)c
->remoteid
) == -1) {
5447 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5448 c ?
"half-open" : "nonexistent", i
));
5451 /* Do pre-close processing on the channel. */
5453 case CHAN_MAINSESSION
:
5454 ssh
->mainchan
= NULL
;
5455 update_specials_menu(ssh
->frontend
);
5458 if (c
->u
.x11
.s
!= NULL
)
5459 x11_close(c
->u
.x11
.s
);
5466 if (c
->u
.pfd
.s
!= NULL
)
5467 pfd_close(c
->u
.pfd
.s
);
5471 if (c
->closes
== 0) {
5472 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5473 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5474 ssh2_pkt_send(ssh
, pktout
);
5476 del234(ssh
->channels
, c
);
5477 bufchain_clear(&c
->v
.v2
.outbuffer
);
5481 * See if that was the last channel left open.
5482 * (This is only our termination condition if we're
5483 * not running in -N mode.)
5485 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
5486 logevent("All channels closed. Disconnecting");
5489 * We used to send SSH_MSG_DISCONNECT here,
5490 * because I'd believed that _every_ conforming
5491 * SSH2 connection had to end with a disconnect
5492 * being sent by at least one side; apparently
5493 * I was wrong and it's perfectly OK to
5494 * unceremoniously slam the connection shut
5495 * when you're done, and indeed OpenSSH feels
5496 * this is more polite than sending a
5497 * DISCONNECT. So now we don't.
5499 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5500 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5501 ssh2_pkt_addstring(s
->pktout
, "All open channels closed");
5502 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
5503 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5505 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5509 static void ssh2_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
5511 unsigned i
= ssh_pkt_getuint32(pktin
);
5512 struct ssh_channel
*c
;
5513 struct Packet
*pktout
;
5515 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5517 return; /* nonexistent channel */
5518 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5519 return; /* dunno why they're confirming this */
5520 c
->remoteid
= ssh_pkt_getuint32(pktin
);
5521 c
->type
= CHAN_SOCKDATA
;
5522 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
5523 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
5525 pfd_confirm(c
->u
.pfd
.s
);
5528 * We have a pending close on this channel,
5529 * which we decided on before the server acked
5530 * the channel open. So now we know the
5531 * remoteid, we can close it again.
5533 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5534 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5535 ssh2_pkt_send(ssh
, pktout
);
5539 static void ssh2_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
5541 static const char *const reasons
[] = {
5542 "<unknown reason code>",
5543 "Administratively prohibited",
5545 "Unknown channel type",
5546 "Resource shortage",
5548 unsigned i
= ssh_pkt_getuint32(pktin
);
5549 unsigned reason_code
;
5550 char *reason_string
;
5553 struct ssh_channel
*c
;
5554 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5556 return; /* nonexistent channel */
5557 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5558 return; /* dunno why they're failing this */
5560 reason_code
= ssh_pkt_getuint32(pktin
);
5561 if (reason_code
>= lenof(reasons
))
5562 reason_code
= 0; /* ensure reasons[reason_code] in range */
5563 ssh_pkt_getstring(pktin
, &reason_string
, &reason_length
);
5564 message
= dupprintf("Forwarded connection refused by"
5565 " server: %s [%.*s]", reasons
[reason_code
],
5566 reason_length
, reason_string
);
5570 pfd_close(c
->u
.pfd
.s
);
5572 del234(ssh
->channels
, c
);
5576 static void ssh2_msg_channel_request(Ssh ssh
, struct Packet
*pktin
)
5580 int typelen
, want_reply
;
5581 int reply
= SSH2_MSG_CHANNEL_FAILURE
; /* default */
5582 struct ssh_channel
*c
;
5583 struct Packet
*pktout
;
5585 localid
= ssh_pkt_getuint32(pktin
);
5586 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5587 want_reply
= ssh2_pkt_getbool(pktin
);
5590 * First, check that the channel exists. Otherwise,
5591 * we can instantly disconnect with a rude message.
5593 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
5596 sprintf(buf
, "Received channel request for nonexistent"
5597 " channel %d", localid
);
5599 pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5600 ssh2_pkt_adduint32(pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5601 ssh2_pkt_addstring(pktout
, buf
);
5602 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5603 ssh2_pkt_send_noqueue(ssh
, pktout
);
5604 connection_fatal(ssh
->frontend
, "%s", buf
);
5605 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5610 * Having got the channel number, we now look at
5611 * the request type string to see if it's something
5614 if (c
== ssh
->mainchan
) {
5616 * We recognise "exit-status" and "exit-signal" on
5617 * the primary channel.
5619 if (typelen
== 11 &&
5620 !memcmp(type
, "exit-status", 11)) {
5622 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
5623 logeventf(ssh
, "Server sent command exit status %d",
5625 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5627 } else if (typelen
== 11 &&
5628 !memcmp(type
, "exit-signal", 11)) {
5630 int is_plausible
= TRUE
, is_int
= FALSE
;
5631 char *fmt_sig
= "", *fmt_msg
= "";
5633 int msglen
= 0, core
= FALSE
;
5634 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
5635 * provide an `int' for the signal, despite its
5636 * having been a `string' in the drafts since at
5637 * least 2001. (Fixed in session.c 1.147.) Try to
5638 * infer which we can safely parse it as. */
5640 unsigned char *p
= pktin
->body
+
5642 long len
= pktin
->length
- pktin
->savedpos
;
5643 unsigned long num
= GET_32BIT(p
); /* what is it? */
5644 /* If it's 0, it hardly matters; assume string */
5648 int maybe_int
= FALSE
, maybe_str
= FALSE
;
5649 #define CHECK_HYPOTHESIS(offset, result) \
5652 if (q >= 0 && q+4 <= len) { \
5653 q = q + 4 + GET_32BIT(p+q); \
5654 if (q >= 0 && q+4 <= len && \
5655 (q = q + 4 + GET_32BIT(p+q)) && q == len) \
5659 CHECK_HYPOTHESIS(4+1, maybe_int
);
5660 CHECK_HYPOTHESIS(4+num
+1, maybe_str
);
5661 #undef CHECK_HYPOTHESIS
5662 if (maybe_int
&& !maybe_str
)
5664 else if (!maybe_int
&& maybe_str
)
5667 /* Crikey. Either or neither. Panic. */
5668 is_plausible
= FALSE
;
5673 /* Old non-standard OpenSSH. */
5674 int signum
= ssh_pkt_getuint32(pktin
);
5675 fmt_sig
= dupprintf(" %d", signum
);
5677 /* As per the drafts. */
5680 ssh_pkt_getstring(pktin
, &sig
, &siglen
);
5681 /* Signal name isn't supposed to be blank, but
5682 * let's cope gracefully if it is. */
5684 fmt_sig
= dupprintf(" \"%.*s\"",
5688 core
= ssh2_pkt_getbool(pktin
);
5689 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
5691 fmt_msg
= dupprintf(" (\"%.*s\")", msglen
, msg
);
5693 /* ignore lang tag */
5694 } /* else don't attempt to parse */
5695 logeventf(ssh
, "Server exited on signal%s%s%s",
5696 fmt_sig
, core ?
" (core dumped)" : "",
5698 if (*fmt_sig
) sfree(fmt_sig
);
5699 if (*fmt_msg
) sfree(fmt_msg
);
5700 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5705 * This is a channel request we don't know
5706 * about, so we now either ignore the request
5707 * or respond with CHANNEL_FAILURE, depending
5710 reply
= SSH2_MSG_CHANNEL_FAILURE
;
5713 pktout
= ssh2_pkt_init(reply
);
5714 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5715 ssh2_pkt_send(ssh
, pktout
);
5719 static void ssh2_msg_global_request(Ssh ssh
, struct Packet
*pktin
)
5722 int typelen
, want_reply
;
5723 struct Packet
*pktout
;
5725 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5726 want_reply
= ssh2_pkt_getbool(pktin
);
5729 * We currently don't support any global requests
5730 * at all, so we either ignore the request or
5731 * respond with REQUEST_FAILURE, depending on
5735 pktout
= ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
5736 ssh2_pkt_send(ssh
, pktout
);
5740 static void ssh2_msg_channel_open(Ssh ssh
, struct Packet
*pktin
)
5748 struct ssh_channel
*c
;
5749 unsigned remid
, winsize
, pktsize
;
5750 struct Packet
*pktout
;
5752 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5753 c
= snew(struct ssh_channel
);
5756 remid
= ssh_pkt_getuint32(pktin
);
5757 winsize
= ssh_pkt_getuint32(pktin
);
5758 pktsize
= ssh_pkt_getuint32(pktin
);
5760 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5763 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5764 addrstr
= snewn(peeraddrlen
+1, char);
5765 memcpy(addrstr
, peeraddr
, peeraddrlen
);
5766 addrstr
[peeraddrlen
] = '\0';
5767 peerport
= ssh_pkt_getuint32(pktin
);
5769 logeventf(ssh
, "Received X11 connect request from %s:%d",
5772 if (!ssh
->X11_fwd_enabled
)
5773 error
= "X11 forwarding is not enabled";
5774 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
5775 ssh
->x11auth
, addrstr
, peerport
,
5776 &ssh
->cfg
) != NULL
) {
5777 error
= "Unable to open an X11 connection";
5779 logevent("Opening X11 forward connection succeeded");
5784 } else if (typelen
== 15 &&
5785 !memcmp(type
, "forwarded-tcpip", 15)) {
5786 struct ssh_rportfwd pf
, *realpf
;
5789 ssh_pkt_getstring(pktin
, &dummy
, &dummylen
);/* skip address */
5790 pf
.sport
= ssh_pkt_getuint32(pktin
);
5791 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5792 peerport
= ssh_pkt_getuint32(pktin
);
5793 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
5794 logeventf(ssh
, "Received remote port %d open request "
5795 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
5796 if (realpf
== NULL
) {
5797 error
= "Remote port is not recognised";
5799 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
5803 logeventf(ssh
, "Attempting to forward remote port to "
5804 "%s:%d", realpf
->dhost
, realpf
->dport
);
5806 logeventf(ssh
, "Port open failed: %s", e
);
5807 error
= "Port open failed";
5809 logevent("Forwarded port opened successfully");
5810 c
->type
= CHAN_SOCKDATA
;
5813 } else if (typelen
== 22 &&
5814 !memcmp(type
, "auth-agent@openssh.com", 3)) {
5815 if (!ssh
->agentfwd_enabled
)
5816 error
= "Agent forwarding is not enabled";
5818 c
->type
= CHAN_AGENT
; /* identify channel type */
5819 c
->u
.a
.lensofar
= 0;
5822 error
= "Unsupported channel type requested";
5825 c
->remoteid
= remid
;
5827 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
5828 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5829 ssh2_pkt_adduint32(pktout
, SSH2_OPEN_CONNECT_FAILED
);
5830 ssh2_pkt_addstring(pktout
, error
);
5831 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5832 ssh2_pkt_send(ssh
, pktout
);
5833 logeventf(ssh
, "Rejected channel open: %s", error
);
5836 c
->localid
= alloc_channel_id(ssh
);
5838 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5839 c
->v
.v2
.remwindow
= winsize
;
5840 c
->v
.v2
.remmaxpkt
= pktsize
;
5841 bufchain_init(&c
->v
.v2
.outbuffer
);
5842 add234(ssh
->channels
, c
);
5843 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
5844 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5845 ssh2_pkt_adduint32(pktout
, c
->localid
);
5846 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);
5847 ssh2_pkt_adduint32(pktout
, 0x4000UL
); /* our max pkt size */
5848 ssh2_pkt_send(ssh
, pktout
);
5853 * Handle the SSH2 userauth and connection layers.
5855 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
5856 struct Packet
*pktin
)
5858 struct do_ssh2_authconn_state
{
5860 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
5862 AUTH_KEYBOARD_INTERACTIVE
5866 AUTH_TYPE_PUBLICKEY
,
5867 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
5868 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
5870 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
5871 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
5873 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
5874 int tried_pubkey_config
, tried_agent
, tried_keyb_inter
;
5875 int kbd_inter_running
;
5877 int num_prompts
, curr_prompt
, echo
;
5882 void *publickey_blob
;
5883 int publickey_bloblen
;
5884 unsigned char request
[5], *response
, *p
;
5888 char *pkblob
, *alg
, *commentp
;
5889 int pklen
, alglen
, commentlen
;
5890 int siglen
, retlen
, len
;
5891 char *q
, *agentreq
, *ret
;
5893 int num_env
, env_left
, env_ok
;
5894 struct Packet
*pktout
;
5896 crState(do_ssh2_authconn_state
);
5898 crBegin(ssh
->do_ssh2_authconn_crstate
);
5901 * Request userauth protocol, and await a response to it.
5903 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
5904 ssh2_pkt_addstring(s
->pktout
, "ssh-userauth");
5905 ssh2_pkt_send(ssh
, s
->pktout
);
5906 crWaitUntilV(pktin
);
5907 if (pktin
->type
!= SSH2_MSG_SERVICE_ACCEPT
) {
5908 bombout(("Server refused user authentication protocol"));
5913 * We repeat this whole loop, including the username prompt,
5914 * until we manage a successful authentication. If the user
5915 * types the wrong _password_, they can be sent back to the
5916 * beginning to try another username, if this is configured on.
5917 * (If they specify a username in the config, they are never
5918 * asked, even if they do give a wrong password.)
5920 * I think this best serves the needs of
5922 * - the people who have no configuration, no keys, and just
5923 * want to try repeated (username,password) pairs until they
5924 * type both correctly
5926 * - people who have keys and configuration but occasionally
5927 * need to fall back to passwords
5929 * - people with a key held in Pageant, who might not have
5930 * logged in to a particular machine before; so they want to
5931 * type a username, and then _either_ their key will be
5932 * accepted, _or_ they will type a password. If they mistype
5933 * the username they will want to be able to get back and
5936 s
->username
[0] = '\0';
5937 s
->got_username
= FALSE
;
5942 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
5944 * We got a username last time round this loop, and
5945 * with change_username turned off we don't try to get
5948 } else if (!*ssh
->cfg
.username
) {
5949 if (ssh_get_line
&& !ssh_getline_pw_only
) {
5950 if (!ssh_get_line("login as: ",
5951 s
->username
, sizeof(s
->username
), FALSE
)) {
5953 * get_line failed to get a username.
5956 logevent("No username provided. Abandoning session.");
5957 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5961 int ret
; /* need not be saved across crReturn */
5962 c_write_str(ssh
, "login as: ");
5964 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
5966 crWaitUntilV(!pktin
);
5967 ret
= process_userpass_input(ssh
, in
, inlen
);
5971 c_write_str(ssh
, "\r\n");
5973 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
5976 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
5977 s
->username
[sizeof(s
->username
)-1] = '\0';
5978 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
5979 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
5980 c_write_str(ssh
, stuff
);
5984 s
->got_username
= TRUE
;
5987 * Send an authentication request using method "none": (a)
5988 * just in case it succeeds, and (b) so that we know what
5989 * authentication methods we can usefully try next.
5991 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5993 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
5994 ssh2_pkt_addstring(s
->pktout
, s
->username
);
5995 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");/* service requested */
5996 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
5997 ssh2_pkt_send(ssh
, s
->pktout
);
5998 s
->type
= AUTH_TYPE_NONE
;
6000 s
->we_are_in
= FALSE
;
6002 s
->tried_pubkey_config
= FALSE
;
6003 s
->tried_agent
= FALSE
;
6004 s
->tried_keyb_inter
= FALSE
;
6005 s
->kbd_inter_running
= FALSE
;
6006 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
6007 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
6009 logeventf(ssh
, "Reading private key file \"%.150s\"",
6010 filename_to_str(&ssh
->cfg
.keyfile
));
6011 keytype
= key_type(&ssh
->cfg
.keyfile
);
6012 if (keytype
== SSH_KEYTYPE_SSH2
) {
6014 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
6015 &s
->publickey_bloblen
, NULL
);
6018 logeventf(ssh
, "Unable to use this key file (%s)",
6019 key_type_to_str(keytype
));
6020 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
6022 filename_to_str(&ssh
->cfg
.keyfile
),
6023 key_type_to_str(keytype
));
6024 c_write_str(ssh
, msgbuf
);
6026 s
->publickey_blob
= NULL
;
6029 s
->publickey_blob
= NULL
;
6033 * Wait for the result of the last authentication request.
6036 crWaitUntilV(pktin
);
6037 while (pktin
->type
== SSH2_MSG_USERAUTH_BANNER
) {
6041 * Don't show the banner if we're operating in
6042 * non-verbose non-interactive mode. (It's probably
6043 * a script, which means nobody will read the
6044 * banner _anyway_, and moreover the printing of
6045 * the banner will screw up processing on the
6046 * output of (say) plink.)
6048 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
6049 ssh_pkt_getstring(pktin
, &banner
, &size
);
6051 c_write_untrusted(ssh
, banner
, size
);
6053 crWaitUntilV(pktin
);
6055 if (pktin
->type
== SSH2_MSG_USERAUTH_SUCCESS
) {
6056 logevent("Access granted");
6057 s
->we_are_in
= TRUE
;
6061 if (s
->kbd_inter_running
&&
6062 pktin
->type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6064 * This is either a further set-of-prompts packet
6065 * in keyboard-interactive authentication, or it's
6066 * the same one and we came back here with `gotit'
6067 * set. In the former case, we must reset the
6068 * curr_prompt variable.
6072 } else if (pktin
->type
!= SSH2_MSG_USERAUTH_FAILURE
) {
6073 bombout(("Strange packet received during authentication: type %d",
6081 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6082 * we can look at the string in it and know what we can
6083 * helpfully try next.
6085 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
) {
6088 ssh_pkt_getstring(pktin
, &methods
, &methlen
);
6089 s
->kbd_inter_running
= FALSE
;
6090 if (!ssh2_pkt_getbool(pktin
)) {
6092 * We have received an unequivocal Access
6093 * Denied. This can translate to a variety of
6096 * - if we'd just tried "none" authentication,
6097 * it's not worth printing anything at all
6099 * - if we'd just tried a public key _offer_,
6100 * the message should be "Server refused our
6101 * key" (or no message at all if the key
6102 * came from Pageant)
6104 * - if we'd just tried anything else, the
6105 * message really should be "Access denied".
6107 * Additionally, if we'd just tried password
6108 * authentication, we should break out of this
6109 * whole loop so as to go back to the username
6110 * prompt (iff we're configured to allow
6111 * username change attempts).
6113 if (s
->type
== AUTH_TYPE_NONE
) {
6115 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
6116 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
6117 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
6118 c_write_str(ssh
, "Server refused our key\r\n");
6119 logevent("Server refused public key");
6120 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
6121 /* server declined keyboard-interactive; ignore */
6123 c_write_str(ssh
, "Access denied\r\n");
6124 logevent("Access denied");
6125 if (s
->type
== AUTH_TYPE_PASSWORD
&&
6126 ssh
->cfg
.change_username
) {
6127 /* XXX perhaps we should allow
6128 * keyboard-interactive to do this too? */
6129 s
->we_are_in
= FALSE
;
6134 c_write_str(ssh
, "Further authentication required\r\n");
6135 logevent("Further authentication required");
6139 in_commasep_string("publickey", methods
, methlen
);
6141 in_commasep_string("password", methods
, methlen
);
6142 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
6143 in_commasep_string("keyboard-interactive", methods
, methlen
);
6147 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6151 * Most password/passphrase prompts will be
6152 * non-echoing, so we set this to 0 by default.
6153 * Exception is that some keyboard-interactive prompts
6154 * can be echoing, in which case we'll set this to 1.
6158 if (!s
->method
&& s
->can_pubkey
&&
6159 agent_exists() && !s
->tried_agent
) {
6161 * Attempt public-key authentication using Pageant.
6166 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6167 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6169 s
->tried_agent
= TRUE
;
6171 logevent("Pageant is running. Requesting keys.");
6173 /* Request the keys held by the agent. */
6174 PUT_32BIT(s
->request
, 1);
6175 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
6176 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
6177 ssh_agent_callback
, ssh
)) {
6181 bombout(("Unexpected data from server while"
6182 " waiting for agent response"));
6185 } while (pktin
|| inlen
> 0);
6186 r
= ssh
->agent_response
;
6187 s
->responselen
= ssh
->agent_response_len
;
6189 s
->response
= (unsigned char *) r
;
6190 if (s
->response
&& s
->responselen
>= 5 &&
6191 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
6192 s
->p
= s
->response
+ 5;
6193 s
->nkeys
= GET_32BIT(s
->p
);
6197 sprintf(buf
, "Pageant has %d SSH2 keys", s
->nkeys
);
6200 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
6205 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
6208 s
->pklen
= GET_32BIT(s
->p
);
6210 if (s
->publickey_blob
&&
6211 s
->pklen
== s
->publickey_bloblen
&&
6212 !memcmp(s
->p
, s
->publickey_blob
,
6213 s
->publickey_bloblen
)) {
6214 logevent("This key matches configured key file");
6215 s
->tried_pubkey_config
= 1;
6217 s
->pkblob
= (char *)s
->p
;
6219 s
->alglen
= GET_32BIT(s
->pkblob
);
6220 s
->alg
= s
->pkblob
+ 4;
6221 s
->commentlen
= GET_32BIT(s
->p
);
6223 s
->commentp
= (char *)s
->p
;
6224 s
->p
+= s
->commentlen
;
6225 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6226 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6227 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6228 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6229 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6230 ssh2_pkt_addstring_start(s
->pktout
);
6231 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6232 ssh2_pkt_addstring_start(s
->pktout
);
6233 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6234 ssh2_pkt_send(ssh
, s
->pktout
);
6236 crWaitUntilV(pktin
);
6237 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6238 logevent("Key refused");
6242 if (flags
& FLAG_VERBOSE
) {
6243 c_write_str(ssh
, "Authenticating with "
6245 c_write(ssh
, s
->commentp
, s
->commentlen
);
6246 c_write_str(ssh
, "\" from agent\r\n");
6250 * Server is willing to accept the key.
6251 * Construct a SIGN_REQUEST.
6253 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6254 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6255 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6256 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6257 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6258 ssh2_pkt_addstring_start(s
->pktout
);
6259 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6260 ssh2_pkt_addstring_start(s
->pktout
);
6261 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6263 s
->siglen
= s
->pktout
->length
- 5 + 4 + 20;
6264 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6266 s
->len
= 1; /* message type */
6267 s
->len
+= 4 + s
->pklen
; /* key blob */
6268 s
->len
+= 4 + s
->siglen
; /* data to sign */
6269 s
->len
+= 4; /* flags */
6270 s
->agentreq
= snewn(4 + s
->len
, char);
6271 PUT_32BIT(s
->agentreq
, s
->len
);
6272 s
->q
= s
->agentreq
+ 4;
6273 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
6274 PUT_32BIT(s
->q
, s
->pklen
);
6276 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
6278 PUT_32BIT(s
->q
, s
->siglen
);
6280 /* Now the data to be signed... */
6281 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6282 PUT_32BIT(s
->q
, 20);
6285 memcpy(s
->q
, ssh
->v2_session_id
, 20);
6287 memcpy(s
->q
, s
->pktout
->data
+ 5,
6288 s
->pktout
->length
- 5);
6289 s
->q
+= s
->pktout
->length
- 5;
6290 /* And finally the (zero) flags word. */
6292 if (!agent_query(s
->agentreq
, s
->len
+ 4,
6294 ssh_agent_callback
, ssh
)) {
6298 bombout(("Unexpected data from server"
6299 " while waiting for agent"
6303 } while (pktin
|| inlen
> 0);
6304 vret
= ssh
->agent_response
;
6305 s
->retlen
= ssh
->agent_response_len
;
6310 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
6311 logevent("Sending Pageant's response");
6312 ssh2_add_sigblob(ssh
, s
->pktout
,
6313 s
->pkblob
, s
->pklen
,
6315 GET_32BIT(s
->ret
+ 5));
6316 ssh2_pkt_send(ssh
, s
->pktout
);
6321 ("Pageant failed to answer challenge");
6332 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
6333 && !s
->tried_pubkey_config
) {
6334 unsigned char *pub_blob
;
6335 char *algorithm
, *comment
;
6338 s
->tried_pubkey_config
= TRUE
;
6340 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6341 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6344 * Try the public key supplied in the configuration.
6346 * First, offer the public blob to see if the server is
6347 * willing to accept it.
6350 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
6355 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6356 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6357 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6358 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6359 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6360 ssh2_pkt_addstring(s
->pktout
, algorithm
);
6361 ssh2_pkt_addstring_start(s
->pktout
);
6362 ssh2_pkt_addstring_data(s
->pktout
, (char *)pub_blob
,
6364 ssh2_pkt_send(ssh
, s
->pktout
);
6365 logevent("Offered public key");
6367 crWaitUntilV(pktin
);
6368 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6370 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
6371 continue; /* key refused; give up on it */
6374 logevent("Offer of public key accepted");
6376 * Actually attempt a serious authentication using
6379 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
6380 sprintf(s
->pwprompt
,
6381 "Passphrase for key \"%.100s\": ",
6387 if (flags
& FLAG_VERBOSE
) {
6388 c_write_str(ssh
, "Authenticating with public key \"");
6389 c_write_str(ssh
, comment
);
6390 c_write_str(ssh
, "\"\r\n");
6392 s
->method
= AUTH_PUBLICKEY_FILE
;
6396 if (!s
->method
&& s
->can_keyb_inter
&& !s
->tried_keyb_inter
) {
6397 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6398 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6399 s
->tried_keyb_inter
= TRUE
;
6401 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6402 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6404 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6405 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6406 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6407 ssh2_pkt_addstring(s
->pktout
, "keyboard-interactive"); /* method */
6408 ssh2_pkt_addstring(s
->pktout
, ""); /* lang */
6409 ssh2_pkt_addstring(s
->pktout
, "");
6410 ssh2_pkt_send(ssh
, s
->pktout
);
6412 crWaitUntilV(pktin
);
6413 if (pktin
->type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6414 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
)
6416 logevent("Keyboard-interactive authentication refused");
6417 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
6421 s
->kbd_inter_running
= TRUE
;
6425 if (s
->kbd_inter_running
) {
6426 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6427 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6428 s
->tried_keyb_inter
= TRUE
;
6430 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6431 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6433 if (s
->curr_prompt
== 0) {
6435 * We've got a fresh USERAUTH_INFO_REQUEST.
6436 * Display header data, and start going through
6439 char *name
, *inst
, *lang
;
6440 int name_len
, inst_len
, lang_len
;
6442 ssh_pkt_getstring(pktin
, &name
, &name_len
);
6443 ssh_pkt_getstring(pktin
, &inst
, &inst_len
);
6444 ssh_pkt_getstring(pktin
, &lang
, &lang_len
);
6446 c_write_untrusted(ssh
, name
, name_len
);
6447 c_write_str(ssh
, "\r\n");
6450 c_write_untrusted(ssh
, inst
, inst_len
);
6451 c_write_str(ssh
, "\r\n");
6453 s
->num_prompts
= ssh_pkt_getuint32(pktin
);
6457 * If there are prompts remaining in the packet,
6458 * display one and get a response.
6460 if (s
->curr_prompt
< s
->num_prompts
) {
6464 ssh_pkt_getstring(pktin
, &prompt
, &prompt_len
);
6465 if (prompt_len
> 0) {
6466 static const char trunc
[] = "<prompt truncated>: ";
6467 static const int prlen
= sizeof(s
->pwprompt
) -
6469 if (prompt_len
> prlen
) {
6470 memcpy(s
->pwprompt
, prompt
, prlen
);
6471 strcpy(s
->pwprompt
+ prlen
, trunc
);
6473 memcpy(s
->pwprompt
, prompt
, prompt_len
);
6474 s
->pwprompt
[prompt_len
] = '\0';
6478 "<server failed to send prompt>: ");
6480 s
->echo
= ssh2_pkt_getbool(pktin
);
6486 if (!s
->method
&& s
->can_passwd
) {
6487 s
->method
= AUTH_PASSWORD
;
6488 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6489 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
6490 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
6497 if (!ssh_get_line(s
->pwprompt
, s
->password
,
6498 sizeof(s
->password
), TRUE
)) {
6500 * get_line failed to get a password (for
6501 * example because one was supplied on the
6502 * command line which has already failed to
6505 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6506 ssh2_pkt_adduint32(s
->pktout
,SSH2_DISCONNECT_BY_APPLICATION
);
6507 ssh2_pkt_addstring(s
->pktout
, "No more passwords available"
6509 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6510 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6511 logevent("Unable to authenticate");
6512 connection_fatal(ssh
->frontend
,
6513 "Unable to authenticate");
6514 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6518 int ret
; /* need not be saved across crReturn */
6519 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
6522 setup_userpass_input(ssh
, s
->password
,
6523 sizeof(s
->password
), s
->echo
);
6525 crWaitUntilV(!pktin
);
6526 ret
= process_userpass_input(ssh
, in
, inlen
);
6530 c_write_str(ssh
, "\r\n");
6534 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
6536 * We have our passphrase. Now try the actual authentication.
6538 struct ssh2_userkey
*key
;
6539 const char *error
= NULL
;
6541 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
,
6543 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
6544 if (key
== SSH2_WRONG_PASSPHRASE
) {
6545 c_write_str(ssh
, "Wrong passphrase\r\n");
6546 s
->tried_pubkey_config
= FALSE
;
6548 c_write_str(ssh
, "Unable to load private key (");
6549 c_write_str(ssh
, error
);
6550 c_write_str(ssh
, ")\r\n");
6551 s
->tried_pubkey_config
= TRUE
;
6553 /* Send a spurious AUTH_NONE to return to the top. */
6554 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6555 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6556 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6557 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6558 ssh2_pkt_send(ssh
, s
->pktout
);
6559 s
->type
= AUTH_TYPE_NONE
;
6561 unsigned char *pkblob
, *sigblob
, *sigdata
;
6562 int pkblob_len
, sigblob_len
, sigdata_len
;
6566 * We have loaded the private key and the server
6567 * has announced that it's willing to accept it.
6568 * Hallelujah. Generate a signature and send it.
6570 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6571 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6572 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6573 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6574 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6575 ssh2_pkt_addstring(s
->pktout
, key
->alg
->name
);
6576 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
6577 ssh2_pkt_addstring_start(s
->pktout
);
6578 ssh2_pkt_addstring_data(s
->pktout
, (char *)pkblob
, pkblob_len
);
6581 * The data to be signed is:
6585 * followed by everything so far placed in the
6588 sigdata_len
= s
->pktout
->length
- 5 + 4 + 20;
6589 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6591 sigdata
= snewn(sigdata_len
, unsigned char);
6593 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6594 PUT_32BIT(sigdata
+p
, 20);
6597 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
6598 memcpy(sigdata
+p
, s
->pktout
->data
+ 5,
6599 s
->pktout
->length
- 5);
6600 p
+= s
->pktout
->length
- 5;
6601 assert(p
== sigdata_len
);
6602 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
6603 sigdata_len
, &sigblob_len
);
6604 ssh2_add_sigblob(ssh
, s
->pktout
, pkblob
, pkblob_len
,
6605 sigblob
, sigblob_len
);
6610 ssh2_pkt_send(ssh
, s
->pktout
);
6611 s
->type
= AUTH_TYPE_PUBLICKEY
;
6612 key
->alg
->freekey(key
->data
);
6614 } else if (s
->method
== AUTH_PASSWORD
) {
6616 * We send the password packet lumped tightly together with
6617 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
6618 * string long enough to make the total length of the two
6619 * packets constant. This should ensure that a passive
6620 * listener doing traffic analyis can't work out the length
6623 * For this to work, we need an assumption about the
6624 * maximum length of the password packet. I think 256 is
6625 * pretty conservative. Anyone using a password longer than
6626 * that probably doesn't have much to worry about from
6627 * people who find out how long their password is!
6629 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6630 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6631 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6632 ssh2_pkt_addstring(s
->pktout
, "password");
6633 ssh2_pkt_addbool(s
->pktout
, FALSE
);
6634 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6635 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6636 memset(s
->password
, 0, sizeof(s
->password
));
6637 end_log_omission(ssh
, s
->pktout
);
6638 ssh2_pkt_defer(ssh
, s
->pktout
);
6640 * We'll include a string that's an exact multiple of the
6641 * cipher block size. If the cipher is NULL for some
6642 * reason, we don't do this trick at all because we gain
6645 if (ssh
->cscipher
) {
6648 stringlen
= (256 - ssh
->deferred_len
);
6649 stringlen
+= ssh
->cscipher
->blksize
- 1;
6650 stringlen
-= (stringlen
% ssh
->cscipher
->blksize
);
6653 * Temporarily disable actual compression,
6654 * so we can guarantee to get this string
6655 * exactly the length we want it. The
6656 * compression-disabling routine should
6657 * return an integer indicating how many
6658 * bytes we should adjust our string length
6662 ssh
->cscomp
->disable_compression(ssh
->cs_comp_ctx
);
6664 s
->pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
6665 ssh2_pkt_addstring_start(s
->pktout
);
6666 for (i
= 0; i
< stringlen
; i
++) {
6667 char c
= (char) random_byte();
6668 ssh2_pkt_addstring_data(s
->pktout
, &c
, 1);
6670 ssh2_pkt_defer(ssh
, s
->pktout
);
6672 ssh_pkt_defersend(ssh
);
6673 logevent("Sent password");
6674 s
->type
= AUTH_TYPE_PASSWORD
;
6675 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
6676 if (s
->curr_prompt
== 0) {
6677 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
6678 ssh2_pkt_adduint32(s
->pktout
, s
->num_prompts
);
6680 if (s
->need_pw
) { /* only add pw if we just got one! */
6681 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6682 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6683 memset(s
->password
, 0, sizeof(s
->password
));
6684 end_log_omission(ssh
, s
->pktout
);
6687 if (s
->curr_prompt
>= s
->num_prompts
) {
6688 ssh2_pkt_send(ssh
, s
->pktout
);
6691 * If there are prompts remaining, we set
6692 * `gotit' so that we won't attempt to get
6693 * another packet. Then we go back round the
6694 * loop and will end up retrieving another
6695 * prompt out of the existing packet. Funky or
6700 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6702 c_write_str(ssh
, "No supported authentication methods"
6703 " left to try!\r\n");
6704 logevent("No supported authentications offered."
6706 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6707 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
6708 ssh2_pkt_addstring(s
->pktout
, "No supported authentication"
6709 " methods available");
6710 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6711 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6712 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6716 } while (!s
->we_are_in
);
6719 * Now we're authenticated for the connection protocol. The
6720 * connection protocol will automatically have started at this
6721 * point; there's no need to send SERVICE_REQUEST.
6724 ssh
->channels
= newtree234(ssh_channelcmp
);
6727 * Set up handlers for some connection protocol messages, so we
6728 * don't have to handle them repeatedly in this coroutine.
6730 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] =
6731 ssh2_msg_channel_window_adjust
;
6732 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] =
6733 ssh2_msg_global_request
;
6736 * Create the main session channel.
6738 if (!ssh
->cfg
.ssh_no_shell
) {
6739 ssh
->mainchan
= snew(struct ssh_channel
);
6740 ssh
->mainchan
->ssh
= ssh
;
6741 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
6742 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
6743 ssh2_pkt_addstring(s
->pktout
, "session");
6744 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->localid
);
6745 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6746 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
6747 ssh2_pkt_adduint32(s
->pktout
, 0x4000UL
); /* our max pkt size */
6748 ssh2_pkt_send(ssh
, s
->pktout
);
6749 crWaitUntilV(pktin
);
6750 if (pktin
->type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
6751 bombout(("Server refused to open a session"));
6753 /* FIXME: error data comes back in FAILURE packet */
6755 if (ssh_pkt_getuint32(pktin
) != ssh
->mainchan
->localid
) {
6756 bombout(("Server's channel confirmation cited wrong channel"));
6759 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(pktin
);
6760 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
6761 ssh
->mainchan
->closes
= 0;
6762 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
6763 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
6764 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
6765 add234(ssh
->channels
, ssh
->mainchan
);
6766 update_specials_menu(ssh
->frontend
);
6767 logevent("Opened channel for session");
6769 ssh
->mainchan
= NULL
;
6772 * Now we have a channel, make dispatch table entries for
6773 * general channel-based messages.
6775 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] =
6776 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] =
6777 ssh2_msg_channel_data
;
6778 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = ssh2_msg_channel_eof
;
6779 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = ssh2_msg_channel_close
;
6780 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] =
6781 ssh2_msg_channel_open_confirmation
;
6782 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] =
6783 ssh2_msg_channel_open_failure
;
6784 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] =
6785 ssh2_msg_channel_request
;
6786 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] =
6787 ssh2_msg_channel_open
;
6790 * Potentially enable X11 forwarding.
6792 if (ssh
->mainchan
&& ssh
->cfg
.x11_forward
) {
6793 char proto
[20], data
[64];
6794 logevent("Requesting X11 forwarding");
6795 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
6796 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
6797 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
6798 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6799 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6800 ssh2_pkt_addstring(s
->pktout
, "x11-req");
6801 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6802 ssh2_pkt_addbool(s
->pktout
, 0); /* many connections */
6803 ssh2_pkt_addstring(s
->pktout
, proto
);
6804 ssh2_pkt_addstring(s
->pktout
, data
);
6805 ssh2_pkt_adduint32(s
->pktout
, x11_get_screen_number(ssh
->cfg
.x11_display
));
6806 ssh2_pkt_send(ssh
, s
->pktout
);
6808 crWaitUntilV(pktin
);
6810 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6811 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6812 bombout(("Unexpected response to X11 forwarding request:"
6813 " packet type %d", pktin
->type
));
6816 logevent("X11 forwarding refused");
6818 logevent("X11 forwarding enabled");
6819 ssh
->X11_fwd_enabled
= TRUE
;
6824 * Enable port forwardings.
6826 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
6829 * Potentially enable agent forwarding.
6831 if (ssh
->mainchan
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
6832 logevent("Requesting OpenSSH-style agent forwarding");
6833 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6834 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6835 ssh2_pkt_addstring(s
->pktout
, "auth-agent-req@openssh.com");
6836 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6837 ssh2_pkt_send(ssh
, s
->pktout
);
6839 crWaitUntilV(pktin
);
6841 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6842 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6843 bombout(("Unexpected response to agent forwarding request:"
6844 " packet type %d", pktin
->type
));
6847 logevent("Agent forwarding refused");
6849 logevent("Agent forwarding enabled");
6850 ssh
->agentfwd_enabled
= TRUE
;
6855 * Now allocate a pty for the session.
6857 if (ssh
->mainchan
&& !ssh
->cfg
.nopty
) {
6858 /* Unpick the terminal-speed string. */
6859 /* XXX perhaps we should allow no speeds to be sent. */
6860 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
6861 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
6862 /* Build the pty request. */
6863 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6864 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
6865 ssh2_pkt_addstring(s
->pktout
, "pty-req");
6866 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6867 ssh2_pkt_addstring(s
->pktout
, ssh
->cfg
.termtype
);
6868 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_width
);
6869 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_height
);
6870 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel width */
6871 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel height */
6872 ssh2_pkt_addstring_start(s
->pktout
);
6873 ssh2_pkt_addbyte(s
->pktout
, 128); /* TTY_OP_ISPEED */
6874 ssh2_pkt_adduint32(s
->pktout
, ssh
->ispeed
);
6875 ssh2_pkt_addbyte(s
->pktout
, 129); /* TTY_OP_OSPEED */
6876 ssh2_pkt_adduint32(s
->pktout
, ssh
->ospeed
);
6877 ssh2_pkt_addstring_data(s
->pktout
, "\0", 1); /* TTY_OP_END */
6878 ssh2_pkt_send(ssh
, s
->pktout
);
6879 ssh
->state
= SSH_STATE_INTERMED
;
6881 crWaitUntilV(pktin
);
6883 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6884 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6885 bombout(("Unexpected response to pty request:"
6886 " packet type %d", pktin
->type
));
6889 c_write_str(ssh
, "Server refused to allocate pty\r\n");
6890 ssh
->editing
= ssh
->echoing
= 1;
6892 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
6893 ssh
->ospeed
, ssh
->ispeed
);
6896 ssh
->editing
= ssh
->echoing
= 1;
6900 * Send environment variables.
6902 * Simplest thing here is to send all the requests at once, and
6903 * then wait for a whole bunch of successes or failures.
6905 if (ssh
->mainchan
&& *ssh
->cfg
.environmt
) {
6906 char *e
= ssh
->cfg
.environmt
;
6907 char *var
, *varend
, *val
;
6913 while (*e
&& *e
!= '\t') e
++;
6915 if (*e
== '\t') e
++;
6920 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6921 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6922 ssh2_pkt_addstring(s
->pktout
, "env");
6923 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6924 ssh2_pkt_addstring_start(s
->pktout
);
6925 ssh2_pkt_addstring_data(s
->pktout
, var
, varend
-var
);
6926 ssh2_pkt_addstring(s
->pktout
, val
);
6927 ssh2_pkt_send(ssh
, s
->pktout
);
6932 logeventf(ssh
, "Sent %d environment variables", s
->num_env
);
6935 s
->env_left
= s
->num_env
;
6937 while (s
->env_left
> 0) {
6938 crWaitUntilV(pktin
);
6940 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6941 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6942 bombout(("Unexpected response to environment request:"
6943 " packet type %d", pktin
->type
));
6953 if (s
->env_ok
== s
->num_env
) {
6954 logevent("All environment variables successfully set");
6955 } else if (s
->env_ok
== 0) {
6956 logevent("All environment variables refused");
6957 c_write_str(ssh
, "Server refused to set environment variables\r\n");
6959 logeventf(ssh
, "%d environment variables refused",
6960 s
->num_env
- s
->env_ok
);
6961 c_write_str(ssh
, "Server refused to set all environment variables\r\n");
6966 * Start a shell or a remote command. We may have to attempt
6967 * this twice if the config data has provided a second choice
6970 if (ssh
->mainchan
) while (1) {
6974 if (ssh
->fallback_cmd
) {
6975 subsys
= ssh
->cfg
.ssh_subsys2
;
6976 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
6978 subsys
= ssh
->cfg
.ssh_subsys
;
6979 cmd
= ssh
->cfg
.remote_cmd_ptr
;
6982 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6983 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
6985 ssh2_pkt_addstring(s
->pktout
, "subsystem");
6986 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6987 ssh2_pkt_addstring(s
->pktout
, cmd
);
6989 ssh2_pkt_addstring(s
->pktout
, "exec");
6990 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6991 ssh2_pkt_addstring(s
->pktout
, cmd
);
6993 ssh2_pkt_addstring(s
->pktout
, "shell");
6994 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6996 ssh2_pkt_send(ssh
, s
->pktout
);
6998 crWaitUntilV(pktin
);
7000 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7001 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7002 bombout(("Unexpected response to shell/command request:"
7003 " packet type %d", pktin
->type
));
7007 * We failed to start the command. If this is the
7008 * fallback command, we really are finished; if it's
7009 * not, and if the fallback command exists, try falling
7010 * back to it before complaining.
7012 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
7013 logevent("Primary command failed; attempting fallback");
7014 ssh
->fallback_cmd
= TRUE
;
7017 bombout(("Server refused to start a shell/command"));
7020 logevent("Started a shell/command");
7025 ssh
->state
= SSH_STATE_SESSION
;
7026 if (ssh
->size_needed
)
7027 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
7028 if (ssh
->eof_needed
)
7029 ssh_special(ssh
, TS_EOF
);
7035 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
7040 s
->try_send
= FALSE
;
7044 * _All_ the connection-layer packets we expect to
7045 * receive are now handled by the dispatch table.
7046 * Anything that reaches here must be bogus.
7049 bombout(("Strange packet received: type %d", pktin
->type
));
7051 } else if (ssh
->mainchan
) {
7053 * We have spare data. Add it to the channel buffer.
7055 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
7060 struct ssh_channel
*c
;
7062 * Try to send data on all channels if we can.
7064 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
7067 continue; /* don't send on closing channels */
7068 bufsize
= ssh2_try_send(c
);
7071 case CHAN_MAINSESSION
:
7072 /* stdin need not receive an unthrottle
7073 * notification since it will be polled */
7076 x11_unthrottle(c
->u
.x11
.s
);
7079 /* agent sockets are request/response and need no
7080 * buffer management */
7083 pfd_unthrottle(c
->u
.pfd
.s
);
7095 * Handlers for SSH2 messages that might arrive at any moment.
7097 void ssh2_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
7099 /* log reason code in disconnect message */
7101 int nowlen
, reason
, msglen
;
7103 reason
= ssh_pkt_getuint32(pktin
);
7104 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7106 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
7107 buf
= dupprintf("Received disconnect message (%s)",
7108 ssh2_disconnect_reasons
[reason
]);
7110 buf
= dupprintf("Received disconnect message (unknown"
7111 " type %d)", reason
);
7115 buf
= dupprintf("Disconnection message text: %n%.*s",
7116 &nowlen
, msglen
, msg
);
7118 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7120 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
7121 ssh2_disconnect_reasons
[reason
] : "unknown",
7126 void ssh2_msg_debug(Ssh ssh
, struct Packet
*pktin
)
7128 /* log the debug message */
7133 /* XXX maybe we should actually take notice of this */
7134 always_display
= ssh2_pkt_getbool(pktin
);
7135 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7137 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
7142 void ssh2_msg_something_unimplemented(Ssh ssh
, struct Packet
*pktin
)
7144 struct Packet
*pktout
;
7145 pktout
= ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
7146 ssh2_pkt_adduint32(pktout
, pktin
->sequence
);
7148 * UNIMPLEMENTED messages MUST appear in the same order as the
7149 * messages they respond to. Hence, never queue them.
7151 ssh2_pkt_send_noqueue(ssh
, pktout
);
7155 * Handle the top-level SSH2 protocol.
7157 static void ssh2_protocol_setup(Ssh ssh
)
7162 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7164 for (i
= 0; i
< 256; i
++)
7165 ssh
->packet_dispatch
[i
] = ssh2_msg_something_unimplemented
;
7168 * Any message we actually understand, we set to NULL so that
7169 * the coroutines will get it.
7171 ssh
->packet_dispatch
[SSH2_MSG_UNIMPLEMENTED
] = NULL
;
7172 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_REQUEST
] = NULL
;
7173 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_ACCEPT
] = NULL
;
7174 ssh
->packet_dispatch
[SSH2_MSG_KEXINIT
] = NULL
;
7175 ssh
->packet_dispatch
[SSH2_MSG_NEWKEYS
] = NULL
;
7176 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_INIT
] = NULL
;
7177 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_REPLY
] = NULL
;
7178 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7179 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7180 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_INIT
] = NULL
;
7181 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_REPLY
] = NULL
;
7182 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_REQUEST
] = NULL
;
7183 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_FAILURE
] = NULL
;
7184 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_SUCCESS
] = NULL
;
7185 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
7186 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_PK_OK
] = NULL
;
7187 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7188 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7189 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_INFO_RESPONSE
] = NULL
;
7190 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] = NULL
;
7191 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_SUCCESS
] = NULL
;
7192 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_FAILURE
] = NULL
;
7193 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] = NULL
;
7194 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] = NULL
;
7195 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] = NULL
;
7196 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] = NULL
;
7197 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] = NULL
;
7198 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] = NULL
;
7199 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = NULL
;
7200 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = NULL
;
7201 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] = NULL
;
7202 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_SUCCESS
] = NULL
;
7203 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_FAILURE
] = NULL
;
7206 * These special message types we install handlers for.
7208 ssh
->packet_dispatch
[SSH2_MSG_DISCONNECT
] = ssh2_msg_disconnect
;
7209 ssh
->packet_dispatch
[SSH2_MSG_IGNORE
] = ssh_msg_ignore
; /* shared with ssh1 */
7210 ssh
->packet_dispatch
[SSH2_MSG_DEBUG
] = ssh2_msg_debug
;
7213 static void ssh2_timer(void *ctx
, long now
)
7217 if (!ssh
->kex_in_progress
&& ssh
->cfg
.ssh_rekey_time
!= 0 &&
7218 now
- ssh
->next_rekey
>= 0) {
7219 do_ssh2_transport(ssh
, "Initiating key re-exchange (timeout)",
7224 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
7225 struct Packet
*pktin
)
7227 if (ssh
->state
== SSH_STATE_CLOSED
)
7231 ssh
->incoming_data_size
+= pktin
->encrypted_len
;
7232 if (!ssh
->kex_in_progress
&&
7233 ssh
->max_data_size
!= 0 &&
7234 ssh
->incoming_data_size
> ssh
->max_data_size
)
7235 do_ssh2_transport(ssh
, "Initiating key re-exchange "
7236 "(too much data received)", -1, NULL
);
7239 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
7240 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
7244 if (!ssh
->protocol_initial_phase_done
||
7245 (pktin
&& pktin
->type
>= 20 && pktin
->type
< 50)) {
7246 if (do_ssh2_transport(ssh
, in
, inlen
, pktin
) &&
7247 !ssh
->protocol_initial_phase_done
) {
7248 ssh
->protocol_initial_phase_done
= TRUE
;
7250 * Allow authconn to initialise itself.
7252 do_ssh2_authconn(ssh
, NULL
, 0, NULL
);
7255 do_ssh2_authconn(ssh
, in
, inlen
, pktin
);
7260 * Called to set up the connection.
7262 * Returns an error message, or NULL on success.
7264 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
7266 char *host
, int port
, char **realhost
, int nodelay
,
7272 ssh
= snew(struct ssh_tag
);
7273 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7274 ssh
->version
= 0; /* when not ready yet */
7277 ssh
->v1_cipher_ctx
= NULL
;
7278 ssh
->crcda_ctx
= NULL
;
7279 ssh
->cscipher
= NULL
;
7280 ssh
->cs_cipher_ctx
= NULL
;
7281 ssh
->sccipher
= NULL
;
7282 ssh
->sc_cipher_ctx
= NULL
;
7284 ssh
->cs_mac_ctx
= NULL
;
7286 ssh
->sc_mac_ctx
= NULL
;
7288 ssh
->cs_comp_ctx
= NULL
;
7290 ssh
->sc_comp_ctx
= NULL
;
7292 ssh
->kex_ctx
= NULL
;
7293 ssh
->hostkey
= NULL
;
7295 ssh
->state
= SSH_STATE_PREPACKET
;
7296 ssh
->size_needed
= FALSE
;
7297 ssh
->eof_needed
= FALSE
;
7300 ssh
->deferred_send_data
= NULL
;
7301 ssh
->deferred_len
= 0;
7302 ssh
->deferred_size
= 0;
7303 ssh
->fallback_cmd
= 0;
7305 ssh
->x11auth
= NULL
;
7306 ssh
->v1_compressing
= FALSE
;
7307 ssh
->v2_outgoing_sequence
= 0;
7308 ssh
->ssh1_rdpkt_crstate
= 0;
7309 ssh
->ssh2_rdpkt_crstate
= 0;
7310 ssh
->do_ssh_init_crstate
= 0;
7311 ssh
->ssh_gotdata_crstate
= 0;
7312 ssh
->do_ssh1_connection_crstate
= 0;
7313 ssh
->do_ssh1_login_crstate
= 0;
7314 ssh
->do_ssh2_transport_crstate
= 0;
7315 ssh
->do_ssh2_authconn_crstate
= 0;
7316 ssh
->do_ssh_init_state
= NULL
;
7317 ssh
->do_ssh1_login_state
= NULL
;
7318 ssh
->do_ssh2_transport_state
= NULL
;
7319 ssh
->do_ssh2_authconn_state
= NULL
;
7320 ssh
->mainchan
= NULL
;
7321 ssh
->throttled_all
= 0;
7322 ssh
->v1_stdout_throttling
= 0;
7324 ssh
->queuelen
= ssh
->queuesize
= 0;
7325 ssh
->queueing
= FALSE
;
7326 ssh
->qhead
= ssh
->qtail
= NULL
;
7328 *backend_handle
= ssh
;
7331 if (crypto_startup() == 0)
7332 return "Microsoft high encryption pack not installed!";
7335 ssh
->frontend
= frontend_handle
;
7336 ssh
->term_width
= ssh
->cfg
.width
;
7337 ssh
->term_height
= ssh
->cfg
.height
;
7339 ssh
->channels
= NULL
;
7340 ssh
->rportfwds
= NULL
;
7341 ssh
->portfwds
= NULL
;
7346 ssh
->v1_throttle_count
= 0;
7347 ssh
->overall_bufsize
= 0;
7348 ssh
->fallback_cmd
= 0;
7350 ssh
->protocol
= NULL
;
7352 ssh
->protocol_initial_phase_done
= FALSE
;
7356 ssh
->incoming_data_size
= ssh
->outgoing_data_size
=
7357 ssh
->deferred_data_size
= 0L;
7358 ssh
->max_data_size
= parse_blocksize(ssh
->cfg
.ssh_rekey_data
);
7359 ssh
->kex_in_progress
= FALSE
;
7361 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
7370 static void ssh_free(void *handle
)
7372 Ssh ssh
= (Ssh
) handle
;
7373 struct ssh_channel
*c
;
7374 struct ssh_rportfwd
*pf
;
7376 if (ssh
->v1_cipher_ctx
)
7377 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
7378 if (ssh
->cs_cipher_ctx
)
7379 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
7380 if (ssh
->sc_cipher_ctx
)
7381 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
7382 if (ssh
->cs_mac_ctx
)
7383 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
7384 if (ssh
->sc_mac_ctx
)
7385 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
7386 if (ssh
->cs_comp_ctx
) {
7388 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
7390 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
7392 if (ssh
->sc_comp_ctx
) {
7394 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
7396 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
7399 dh_cleanup(ssh
->kex_ctx
);
7400 sfree(ssh
->savedhost
);
7402 while (ssh
->queuelen
-- > 0)
7403 ssh_free_packet(ssh
->queue
[ssh
->queuelen
]);
7406 while (ssh
->qhead
) {
7407 struct queued_handler
*qh
= ssh
->qhead
;
7408 ssh
->qhead
= qh
->next
;
7411 ssh
->qhead
= ssh
->qtail
= NULL
;
7413 if (ssh
->channels
) {
7414 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
7417 if (c
->u
.x11
.s
!= NULL
)
7418 x11_close(c
->u
.x11
.s
);
7421 if (c
->u
.pfd
.s
!= NULL
)
7422 pfd_close(c
->u
.pfd
.s
);
7427 freetree234(ssh
->channels
);
7428 ssh
->channels
= NULL
;
7431 if (ssh
->rportfwds
) {
7432 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
7434 freetree234(ssh
->rportfwds
);
7435 ssh
->rportfwds
= NULL
;
7437 sfree(ssh
->deferred_send_data
);
7439 x11_free_auth(ssh
->x11auth
);
7440 sfree(ssh
->do_ssh_init_state
);
7441 sfree(ssh
->do_ssh1_login_state
);
7442 sfree(ssh
->do_ssh2_transport_state
);
7443 sfree(ssh
->do_ssh2_authconn_state
);
7444 if (ssh
->crcda_ctx
) {
7445 crcda_free_context(ssh
->crcda_ctx
);
7446 ssh
->crcda_ctx
= NULL
;
7450 expire_timer_context(ssh
);
7452 pinger_free(ssh
->pinger
);
7459 * Reconfigure the SSH backend.
7461 static void ssh_reconfig(void *handle
, Config
*cfg
)
7463 Ssh ssh
= (Ssh
) handle
;
7464 char *rekeying
= NULL
;
7465 unsigned long old_max_data_size
;
7467 pinger_reconfig(ssh
->pinger
, &ssh
->cfg
, cfg
);
7468 ssh_setup_portfwd(ssh
, cfg
);
7470 if (ssh
->cfg
.ssh_rekey_time
!= cfg
->ssh_rekey_time
&&
7471 cfg
->ssh_rekey_time
!= 0) {
7472 long new_next
= ssh
->last_rekey
+ cfg
->ssh_rekey_time
*60*TICKSPERSEC
;
7473 long now
= GETTICKCOUNT();
7475 if (new_next
- now
< 0) {
7476 rekeying
= "Initiating key re-exchange (timeout shortened)";
7478 ssh
->next_rekey
= schedule_timer(new_next
- now
, ssh2_timer
, ssh
);
7482 old_max_data_size
= ssh
->max_data_size
;
7483 ssh
->max_data_size
= parse_blocksize(cfg
->ssh_rekey_data
);
7484 if (old_max_data_size
!= ssh
->max_data_size
&&
7485 ssh
->max_data_size
!= 0) {
7486 if (ssh
->outgoing_data_size
> ssh
->max_data_size
||
7487 ssh
->incoming_data_size
> ssh
->max_data_size
)
7488 rekeying
= "Initiating key re-exchange (data limit lowered)";
7491 if (rekeying
&& !ssh
->kex_in_progress
) {
7492 do_ssh2_transport(ssh
, rekeying
, -1, NULL
);
7495 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7499 * Called to send data down the Telnet connection.
7501 static int ssh_send(void *handle
, char *buf
, int len
)
7503 Ssh ssh
= (Ssh
) handle
;
7505 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7508 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
7510 return ssh_sendbuffer(ssh
);
7514 * Called to query the current amount of buffered stdin data.
7516 static int ssh_sendbuffer(void *handle
)
7518 Ssh ssh
= (Ssh
) handle
;
7521 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7525 * If the SSH socket itself has backed up, add the total backup
7526 * size on that to any individual buffer on the stdin channel.
7529 if (ssh
->throttled_all
)
7530 override_value
= ssh
->overall_bufsize
;
7532 if (ssh
->version
== 1) {
7533 return override_value
;
7534 } else if (ssh
->version
== 2) {
7535 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
7536 return override_value
;
7538 return (override_value
+
7539 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
7546 * Called to set the size of the window from SSH's POV.
7548 static void ssh_size(void *handle
, int width
, int height
)
7550 Ssh ssh
= (Ssh
) handle
;
7551 struct Packet
*pktout
;
7553 ssh
->term_width
= width
;
7554 ssh
->term_height
= height
;
7556 switch (ssh
->state
) {
7557 case SSH_STATE_BEFORE_SIZE
:
7558 case SSH_STATE_PREPACKET
:
7559 case SSH_STATE_CLOSED
:
7560 break; /* do nothing */
7561 case SSH_STATE_INTERMED
:
7562 ssh
->size_needed
= TRUE
; /* buffer for later */
7564 case SSH_STATE_SESSION
:
7565 if (!ssh
->cfg
.nopty
) {
7566 if (ssh
->version
== 1) {
7567 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
7568 PKT_INT
, ssh
->term_height
,
7569 PKT_INT
, ssh
->term_width
,
7570 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
7571 } else if (ssh
->mainchan
) {
7572 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7573 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7574 ssh2_pkt_addstring(pktout
, "window-change");
7575 ssh2_pkt_addbool(pktout
, 0);
7576 ssh2_pkt_adduint32(pktout
, ssh
->term_width
);
7577 ssh2_pkt_adduint32(pktout
, ssh
->term_height
);
7578 ssh2_pkt_adduint32(pktout
, 0);
7579 ssh2_pkt_adduint32(pktout
, 0);
7580 ssh2_pkt_send(ssh
, pktout
);
7588 * Return a list of the special codes that make sense in this
7591 static const struct telnet_special
*ssh_get_specials(void *handle
)
7593 static const struct telnet_special ssh1_ignore_special
[] = {
7594 {"IGNORE message", TS_NOP
}
7596 static const struct telnet_special ssh2_transport_specials
[] = {
7597 {"IGNORE message", TS_NOP
},
7598 {"Repeat key exchange", TS_REKEY
},
7600 static const struct telnet_special ssh2_session_specials
[] = {
7603 /* These are the signal names defined by draft-ietf-secsh-connect-23.
7604 * They include all the ISO C signals, but are a subset of the POSIX
7605 * required signals. */
7606 {"SIGINT (Interrupt)", TS_SIGINT
},
7607 {"SIGTERM (Terminate)", TS_SIGTERM
},
7608 {"SIGKILL (Kill)", TS_SIGKILL
},
7609 {"SIGQUIT (Quit)", TS_SIGQUIT
},
7610 {"SIGHUP (Hangup)", TS_SIGHUP
},
7611 {"More signals", TS_SUBMENU
},
7612 {"SIGABRT", TS_SIGABRT
}, {"SIGALRM", TS_SIGALRM
},
7613 {"SIGFPE", TS_SIGFPE
}, {"SIGILL", TS_SIGILL
},
7614 {"SIGPIPE", TS_SIGPIPE
}, {"SIGSEGV", TS_SIGSEGV
},
7615 {"SIGUSR1", TS_SIGUSR1
}, {"SIGUSR2", TS_SIGUSR2
},
7618 static const struct telnet_special specials_end
[] = {
7621 /* XXX review this length for any changes: */
7622 static struct telnet_special ssh_specials
[lenof(ssh2_transport_specials
) +
7623 lenof(ssh2_session_specials
) +
7624 lenof(specials_end
)];
7625 Ssh ssh
= (Ssh
) handle
;
7627 #define ADD_SPECIALS(name) \
7629 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7630 memcpy(&ssh_specials[i], name, sizeof name); \
7634 if (ssh
->version
== 1) {
7635 /* Don't bother offering IGNORE if we've decided the remote
7636 * won't cope with it, since we wouldn't bother sending it if
7638 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7639 ADD_SPECIALS(ssh1_ignore_special
);
7640 } else if (ssh
->version
== 2) {
7641 ADD_SPECIALS(ssh2_transport_specials
);
7643 ADD_SPECIALS(ssh2_session_specials
);
7644 } /* else we're not ready yet */
7647 ADD_SPECIALS(specials_end
);
7648 return ssh_specials
;
7656 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7657 * can send an EOF and collect resulting output (e.g. `plink
7660 static void ssh_special(void *handle
, Telnet_Special code
)
7662 Ssh ssh
= (Ssh
) handle
;
7663 struct Packet
*pktout
;
7665 if (code
== TS_EOF
) {
7666 if (ssh
->state
!= SSH_STATE_SESSION
) {
7668 * Buffer the EOF in case we are pre-SESSION, so we can
7669 * send it as soon as we reach SESSION.
7672 ssh
->eof_needed
= TRUE
;
7675 if (ssh
->version
== 1) {
7676 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
7677 } else if (ssh
->mainchan
) {
7678 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
7679 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7680 ssh2_pkt_send(ssh
, pktout
);
7682 logevent("Sent EOF message");
7683 } else if (code
== TS_PING
|| code
== TS_NOP
) {
7684 if (ssh
->state
== SSH_STATE_CLOSED
7685 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7686 if (ssh
->version
== 1) {
7687 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7688 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
7690 pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
7691 ssh2_pkt_addstring_start(pktout
);
7692 ssh2_pkt_send_noqueue(ssh
, pktout
);
7694 } else if (code
== TS_REKEY
) {
7695 if (!ssh
->kex_in_progress
&& ssh
->version
== 2) {
7696 do_ssh2_transport(ssh
, "Initiating key re-exchange at"
7697 " user request", -1, NULL
);
7699 } else if (code
== TS_BRK
) {
7700 if (ssh
->state
== SSH_STATE_CLOSED
7701 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7702 if (ssh
->version
== 1) {
7703 logevent("Unable to send BREAK signal in SSH1");
7704 } else if (ssh
->mainchan
) {
7705 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7706 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7707 ssh2_pkt_addstring(pktout
, "break");
7708 ssh2_pkt_addbool(pktout
, 0);
7709 ssh2_pkt_adduint32(pktout
, 0); /* default break length */
7710 ssh2_pkt_send(ssh
, pktout
);
7713 /* Is is a POSIX signal? */
7714 char *signame
= NULL
;
7715 if (code
== TS_SIGABRT
) signame
= "ABRT";
7716 if (code
== TS_SIGALRM
) signame
= "ALRM";
7717 if (code
== TS_SIGFPE
) signame
= "FPE";
7718 if (code
== TS_SIGHUP
) signame
= "HUP";
7719 if (code
== TS_SIGILL
) signame
= "ILL";
7720 if (code
== TS_SIGINT
) signame
= "INT";
7721 if (code
== TS_SIGKILL
) signame
= "KILL";
7722 if (code
== TS_SIGPIPE
) signame
= "PIPE";
7723 if (code
== TS_SIGQUIT
) signame
= "QUIT";
7724 if (code
== TS_SIGSEGV
) signame
= "SEGV";
7725 if (code
== TS_SIGTERM
) signame
= "TERM";
7726 if (code
== TS_SIGUSR1
) signame
= "USR1";
7727 if (code
== TS_SIGUSR2
) signame
= "USR2";
7728 /* The SSH-2 protocol does in principle support arbitrary named
7729 * signals, including signame@domain, but we don't support those. */
7731 /* It's a signal. */
7732 if (ssh
->version
== 2 && ssh
->mainchan
) {
7733 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7734 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7735 ssh2_pkt_addstring(pktout
, "signal");
7736 ssh2_pkt_addbool(pktout
, 0);
7737 ssh2_pkt_addstring(pktout
, signame
);
7738 ssh2_pkt_send(ssh
, pktout
);
7739 logeventf(ssh
, "Sent signal SIG%s", signame
);
7742 /* Never heard of it. Do nothing */
7747 void *new_sock_channel(void *handle
, Socket s
)
7749 Ssh ssh
= (Ssh
) handle
;
7750 struct ssh_channel
*c
;
7751 c
= snew(struct ssh_channel
);
7755 c
->remoteid
= -1; /* to be set when open confirmed */
7756 c
->localid
= alloc_channel_id(ssh
);
7758 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
7760 bufchain_init(&c
->v
.v2
.outbuffer
);
7761 add234(ssh
->channels
, c
);
7767 * This is called when stdout/stderr (the entity to which
7768 * from_backend sends data) manages to clear some backlog.
7770 static void ssh_unthrottle(void *handle
, int bufsize
)
7772 Ssh ssh
= (Ssh
) handle
;
7773 if (ssh
->version
== 1) {
7774 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
7775 ssh
->v1_stdout_throttling
= 0;
7776 ssh1_throttle(ssh
, -1);
7779 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
7780 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
7784 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
7786 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
7788 struct Packet
*pktout
;
7790 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
7792 if (ssh
->version
== 1) {
7793 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
7794 PKT_INT
, c
->localid
,
7797 /* PKT_STR, <org:orgport>, */
7800 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
7801 ssh2_pkt_addstring(pktout
, "direct-tcpip");
7802 ssh2_pkt_adduint32(pktout
, c
->localid
);
7803 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7804 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);/* our window size */
7805 ssh2_pkt_adduint32(pktout
, 0x4000UL
); /* our max pkt size */
7806 ssh2_pkt_addstring(pktout
, hostname
);
7807 ssh2_pkt_adduint32(pktout
, port
);
7809 * We make up values for the originator data; partly it's
7810 * too much hassle to keep track, and partly I'm not
7811 * convinced the server should be told details like that
7812 * about my local network configuration.
7814 ssh2_pkt_addstring(pktout
, "client-side-connection");
7815 ssh2_pkt_adduint32(pktout
, 0);
7816 ssh2_pkt_send(ssh
, pktout
);
7820 static Socket
ssh_socket(void *handle
)
7822 Ssh ssh
= (Ssh
) handle
;
7826 static int ssh_sendok(void *handle
)
7828 Ssh ssh
= (Ssh
) handle
;
7829 return ssh
->send_ok
;
7832 static int ssh_ldisc(void *handle
, int option
)
7834 Ssh ssh
= (Ssh
) handle
;
7835 if (option
== LD_ECHO
)
7836 return ssh
->echoing
;
7837 if (option
== LD_EDIT
)
7838 return ssh
->editing
;
7842 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
7844 Ssh ssh
= (Ssh
) handle
;
7848 static void ssh_provide_logctx(void *handle
, void *logctx
)
7850 Ssh ssh
= (Ssh
) handle
;
7851 ssh
->logctx
= logctx
;
7854 static int ssh_return_exitcode(void *handle
)
7856 Ssh ssh
= (Ssh
) handle
;
7860 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
7864 * cfg_info for SSH is the currently running version of the
7865 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
7867 static int ssh_cfg_info(void *handle
)
7869 Ssh ssh
= (Ssh
) handle
;
7870 return ssh
->version
;
7874 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
7875 * that fails. This variable is the means by which scp.c can reach
7876 * into the SSH code and find out which one it got.
7878 extern int ssh_fallback_cmd(void *handle
)
7880 Ssh ssh
= (Ssh
) handle
;
7881 return ssh
->fallback_cmd
;
7884 Backend ssh_backend
= {
7894 ssh_return_exitcode
,