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
;
527 #define free_portfwd(pf) ( \
528 ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr)) : (void)0 ), sfree(pf) )
533 unsigned long sequence
;
538 long encrypted_len
; /* for SSH2 total-size counting */
541 * State associated with packet logging
545 struct logblank_t
*blanks
;
548 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
549 struct Packet
*pktin
);
550 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
551 struct Packet
*pktin
);
552 static void ssh1_protocol_setup(Ssh ssh
);
553 static void ssh2_protocol_setup(Ssh ssh
);
554 static void ssh_size(void *handle
, int width
, int height
);
555 static void ssh_special(void *handle
, Telnet_Special
);
556 static int ssh2_try_send(struct ssh_channel
*c
);
557 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
558 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
559 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
560 static int ssh_sendbuffer(void *handle
);
561 static void ssh_do_close(Ssh ssh
);
562 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
);
563 static int ssh2_pkt_getbool(struct Packet
*pkt
);
564 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
);
565 static void ssh2_timer(void *ctx
, long now
);
566 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
,
567 struct Packet
*pktin
);
569 struct rdpkt1_state_tag
{
570 long len
, pad
, biglen
, to_read
;
571 unsigned long realcrc
, gotcrc
;
575 struct Packet
*pktin
;
578 struct rdpkt2_state_tag
{
579 long len
, pad
, payload
, packetlen
, maclen
;
582 unsigned long incoming_sequence
;
583 struct Packet
*pktin
;
586 typedef void (*handler_fn_t
)(Ssh ssh
, struct Packet
*pktin
);
587 typedef void (*chandler_fn_t
)(Ssh ssh
, struct Packet
*pktin
, void *ctx
);
589 struct queued_handler
;
590 struct queued_handler
{
592 chandler_fn_t handler
;
594 struct queued_handler
*next
;
598 const struct plug_function_table
*fn
;
599 /* the above field _must_ be first in the structure */
601 SHA_State exhash
, exhashbase
;
608 unsigned char session_key
[32];
610 int v1_remote_protoflags
;
611 int v1_local_protoflags
;
612 int agentfwd_enabled
;
615 const struct ssh_cipher
*cipher
;
618 const struct ssh2_cipher
*cscipher
, *sccipher
;
619 void *cs_cipher_ctx
, *sc_cipher_ctx
;
620 const struct ssh_mac
*csmac
, *scmac
;
621 void *cs_mac_ctx
, *sc_mac_ctx
;
622 const struct ssh_compress
*cscomp
, *sccomp
;
623 void *cs_comp_ctx
, *sc_comp_ctx
;
624 const struct ssh_kex
*kex
;
625 const struct ssh_signkey
*hostkey
;
626 unsigned char v2_session_id
[20];
632 int echoing
, editing
;
636 int ospeed
, ispeed
; /* temporaries */
637 int term_width
, term_height
;
639 tree234
*channels
; /* indexed by local id */
640 struct ssh_channel
*mainchan
; /* primary session channel */
643 tree234
*rportfwds
, *portfwds
;
647 SSH_STATE_BEFORE_SIZE
,
653 int size_needed
, eof_needed
;
655 struct Packet
**queue
;
656 int queuelen
, queuesize
;
658 unsigned char *deferred_send_data
;
659 int deferred_len
, deferred_size
;
662 * Gross hack: pscp will try to start SFTP but fall back to
663 * scp1 if that fails. This variable is the means by which
664 * scp.c can reach into the SSH code and find out which one it
670 * Used for username and password input.
672 char *userpass_input_buffer
;
673 int userpass_input_buflen
;
674 int userpass_input_bufpos
;
675 int userpass_input_echo
;
682 int v1_throttle_count
;
685 int v1_stdout_throttling
;
686 int v2_outgoing_sequence
;
688 int ssh1_rdpkt_crstate
;
689 int ssh2_rdpkt_crstate
;
690 int do_ssh_init_crstate
;
691 int ssh_gotdata_crstate
;
692 int do_ssh1_login_crstate
;
693 int do_ssh1_connection_crstate
;
694 int do_ssh2_transport_crstate
;
695 int do_ssh2_authconn_crstate
;
697 void *do_ssh_init_state
;
698 void *do_ssh1_login_state
;
699 void *do_ssh2_transport_state
;
700 void *do_ssh2_authconn_state
;
702 struct rdpkt1_state_tag rdpkt1_state
;
703 struct rdpkt2_state_tag rdpkt2_state
;
705 /* ssh1 and ssh2 use this for different things, but both use it */
706 int protocol_initial_phase_done
;
708 void (*protocol
) (Ssh ssh
, unsigned char *in
, int inlen
,
710 struct Packet
*(*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
713 * We maintain a full _copy_ of a Config structure here, not
714 * merely a pointer to it. That way, when we're passed a new
715 * one for reconfiguration, we can check the differences and
716 * potentially reconfigure port forwardings etc in mid-session.
721 * Used to transfer data back from async agent callbacks.
723 void *agent_response
;
724 int agent_response_len
;
727 * Dispatch table for packet types that we may have to deal
730 handler_fn_t packet_dispatch
[256];
733 * Queues of one-off handler functions for success/failure
734 * indications from a request.
736 struct queued_handler
*qhead
, *qtail
;
739 * This module deals with sending keepalives.
744 * Track incoming and outgoing data sizes and time, for
747 unsigned long incoming_data_size
, outgoing_data_size
, deferred_data_size
;
748 unsigned long max_data_size
;
750 long next_rekey
, last_rekey
;
753 #define logevent(s) logevent(ssh->frontend, s)
755 /* logevent, only printf-formatted. */
756 static void logeventf(Ssh ssh
, const char *fmt
, ...)
762 buf
= dupvprintf(fmt
, ap
);
768 #define bombout(msg) \
770 char *text = dupprintf msg; \
773 connection_fatal(ssh->frontend, "%s", text); \
777 /* Functions to leave bits out of the SSH packet log file. */
779 static void dont_log_password(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
781 if (ssh
->cfg
.logomitpass
)
782 pkt
->logmode
= blanktype
;
785 static void dont_log_data(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
787 if (ssh
->cfg
.logomitdata
)
788 pkt
->logmode
= blanktype
;
791 static void end_log_omission(Ssh ssh
, struct Packet
*pkt
)
793 pkt
->logmode
= PKTLOG_EMIT
;
796 static int ssh_channelcmp(void *av
, void *bv
)
798 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
799 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
800 if (a
->localid
< b
->localid
)
802 if (a
->localid
> b
->localid
)
806 static int ssh_channelfind(void *av
, void *bv
)
808 unsigned *a
= (unsigned *) av
;
809 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
817 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
819 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
820 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
822 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
823 return i
< 0 ?
-1 : +1;
824 if (a
->dport
> b
->dport
)
826 if (a
->dport
< b
->dport
)
831 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
833 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
834 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
836 if (a
->sport
> b
->sport
)
838 if (a
->sport
< b
->sport
)
844 * Special form of strcmp which can cope with NULL inputs. NULL is
845 * defined to sort before even the empty string.
847 static int nullstrcmp(const char *a
, const char *b
)
849 if (a
== NULL
&& b
== NULL
)
858 static int ssh_portcmp(void *av
, void *bv
)
860 struct ssh_portfwd
*a
= (struct ssh_portfwd
*) av
;
861 struct ssh_portfwd
*b
= (struct ssh_portfwd
*) bv
;
863 if (a
->type
> b
->type
)
865 if (a
->type
< b
->type
)
867 if ( (i
= nullstrcmp(a
->saddr
, b
->saddr
)) != 0)
868 return i
< 0 ?
-1 : +1;
869 if (a
->sport
> b
->sport
)
871 if (a
->sport
< b
->sport
)
873 if (a
->type
!= 'D') {
874 if ( (i
= nullstrcmp(a
->daddr
, b
->daddr
)) != 0)
875 return i
< 0 ?
-1 : +1;
876 if (a
->dport
> b
->dport
)
878 if (a
->dport
< b
->dport
)
884 static int alloc_channel_id(Ssh ssh
)
886 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
887 unsigned low
, high
, mid
;
889 struct ssh_channel
*c
;
892 * First-fit allocation of channel numbers: always pick the
893 * lowest unused one. To do this, binary-search using the
894 * counted B-tree to find the largest channel ID which is in a
895 * contiguous sequence from the beginning. (Precisely
896 * everything in that sequence must have ID equal to its tree
897 * index plus CHANNEL_NUMBER_OFFSET.)
899 tsize
= count234(ssh
->channels
);
903 while (high
- low
> 1) {
904 mid
= (high
+ low
) / 2;
905 c
= index234(ssh
->channels
, mid
);
906 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
907 low
= mid
; /* this one is fine */
909 high
= mid
; /* this one is past it */
912 * Now low points to either -1, or the tree index of the
913 * largest ID in the initial sequence.
916 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
917 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
919 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
922 static void c_write(Ssh ssh
, const char *buf
, int len
)
924 if ((flags
& FLAG_STDERR
)) {
926 for (i
= 0; i
< len
; i
++)
928 fputc(buf
[i
], stderr
);
931 from_backend(ssh
->frontend
, 1, buf
, len
);
934 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
937 for (i
= 0; i
< len
; i
++) {
939 c_write(ssh
, "\r\n", 2);
940 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
941 c_write(ssh
, buf
+ i
, 1);
945 static void c_write_str(Ssh ssh
, const char *buf
)
947 c_write(ssh
, buf
, strlen(buf
));
950 static void ssh_free_packet(struct Packet
*pkt
)
955 static struct Packet
*ssh_new_packet(void)
957 struct Packet
*pkt
= snew(struct Packet
);
961 pkt
->logmode
= PKTLOG_EMIT
;
969 * Collect incoming data in the incoming packet buffer.
970 * Decipher and verify the packet when it is completely read.
971 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
972 * Update the *data and *datalen variables.
973 * Return a Packet structure when a packet is completed.
975 static struct Packet
*ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
977 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
979 crBegin(ssh
->ssh1_rdpkt_crstate
);
981 st
->pktin
= ssh_new_packet();
984 st
->pktin
->length
= 0;
986 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
987 while ((*datalen
) == 0)
989 st
->len
= (st
->len
<< 8) + **data
;
990 (*data
)++, (*datalen
)--;
993 st
->pad
= 8 - (st
->len
% 8);
994 st
->biglen
= st
->len
+ st
->pad
;
995 st
->pktin
->length
= st
->len
- 5;
997 if (st
->biglen
< 0) {
998 bombout(("Extremely large packet length from server suggests"
999 " data stream corruption"));
1000 ssh_free_packet(st
->pktin
);
1004 st
->pktin
->maxlen
= st
->biglen
;
1005 st
->pktin
->data
= snewn(st
->biglen
+ APIEXTRA
, unsigned char);
1007 st
->to_read
= st
->biglen
;
1008 st
->p
= st
->pktin
->data
;
1009 while (st
->to_read
> 0) {
1010 st
->chunk
= st
->to_read
;
1011 while ((*datalen
) == 0)
1013 if (st
->chunk
> (*datalen
))
1014 st
->chunk
= (*datalen
);
1015 memcpy(st
->p
, *data
, st
->chunk
);
1017 *datalen
-= st
->chunk
;
1019 st
->to_read
-= st
->chunk
;
1022 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, st
->pktin
->data
,
1023 st
->biglen
, NULL
)) {
1024 bombout(("Network attack (CRC compensation) detected!"));
1025 ssh_free_packet(st
->pktin
);
1030 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, st
->pktin
->data
, st
->biglen
);
1032 st
->realcrc
= crc32_compute(st
->pktin
->data
, st
->biglen
- 4);
1033 st
->gotcrc
= GET_32BIT(st
->pktin
->data
+ st
->biglen
- 4);
1034 if (st
->gotcrc
!= st
->realcrc
) {
1035 bombout(("Incorrect CRC received on packet"));
1036 ssh_free_packet(st
->pktin
);
1040 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1041 st
->pktin
->savedpos
= 0;
1043 if (ssh
->v1_compressing
) {
1044 unsigned char *decompblk
;
1046 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
1047 st
->pktin
->body
- 1, st
->pktin
->length
+ 1,
1048 &decompblk
, &decomplen
)) {
1049 bombout(("Zlib decompression encountered invalid data"));
1050 ssh_free_packet(st
->pktin
);
1054 if (st
->pktin
->maxlen
< st
->pad
+ decomplen
) {
1055 st
->pktin
->maxlen
= st
->pad
+ decomplen
;
1056 st
->pktin
->data
= sresize(st
->pktin
->data
,
1057 st
->pktin
->maxlen
+ APIEXTRA
,
1059 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1062 memcpy(st
->pktin
->body
- 1, decompblk
, decomplen
);
1064 st
->pktin
->length
= decomplen
- 1;
1067 st
->pktin
->type
= st
->pktin
->body
[-1];
1070 * Log incoming packet, possibly omitting sensitive fields.
1074 struct logblank_t blank
;
1075 if (ssh
->cfg
.logomitdata
) {
1076 int do_blank
= FALSE
, blank_prefix
= 0;
1077 /* "Session data" packets - omit the data field */
1078 if ((st
->pktin
->type
== SSH1_SMSG_STDOUT_DATA
) ||
1079 (st
->pktin
->type
== SSH1_SMSG_STDERR_DATA
)) {
1080 do_blank
= TRUE
; blank_prefix
= 0;
1081 } else if (st
->pktin
->type
== SSH1_MSG_CHANNEL_DATA
) {
1082 do_blank
= TRUE
; blank_prefix
= 4;
1085 blank
.offset
= blank_prefix
;
1086 blank
.len
= st
->pktin
->length
;
1087 blank
.type
= PKTLOG_OMIT
;
1091 log_packet(ssh
->logctx
,
1092 PKT_INCOMING
, st
->pktin
->type
,
1093 ssh1_pkt_type(st
->pktin
->type
),
1094 st
->pktin
->body
, st
->pktin
->length
,
1098 crFinish(st
->pktin
);
1101 static struct Packet
*ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1103 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1105 crBegin(ssh
->ssh2_rdpkt_crstate
);
1107 st
->pktin
= ssh_new_packet();
1109 st
->pktin
->type
= 0;
1110 st
->pktin
->length
= 0;
1112 st
->cipherblk
= ssh
->sccipher
->blksize
;
1115 if (st
->cipherblk
< 8)
1118 st
->pktin
->data
= snewn(st
->cipherblk
+ APIEXTRA
, unsigned char);
1121 * Acquire and decrypt the first block of the packet. This will
1122 * contain the length and padding details.
1124 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1125 while ((*datalen
) == 0)
1127 st
->pktin
->data
[st
->i
] = *(*data
)++;
1132 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1133 st
->pktin
->data
, st
->cipherblk
);
1136 * Now get the length and padding figures.
1138 st
->len
= GET_32BIT(st
->pktin
->data
);
1139 st
->pad
= st
->pktin
->data
[4];
1142 * _Completely_ silly lengths should be stomped on before they
1143 * do us any more damage.
1145 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
1146 bombout(("Incoming packet was garbled on decryption"));
1147 ssh_free_packet(st
->pktin
);
1152 * This enables us to deduce the payload length.
1154 st
->payload
= st
->len
- st
->pad
- 1;
1156 st
->pktin
->length
= st
->payload
+ 5;
1159 * So now we can work out the total packet length.
1161 st
->packetlen
= st
->len
+ 4;
1162 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1165 * Allocate memory for the rest of the packet.
1167 st
->pktin
->maxlen
= st
->packetlen
+ st
->maclen
;
1168 st
->pktin
->data
= sresize(st
->pktin
->data
,
1169 st
->pktin
->maxlen
+ APIEXTRA
,
1173 * Read and decrypt the remainder of the packet.
1175 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1177 while ((*datalen
) == 0)
1179 st
->pktin
->data
[st
->i
] = *(*data
)++;
1182 /* Decrypt everything _except_ the MAC. */
1184 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1185 st
->pktin
->data
+ st
->cipherblk
,
1186 st
->packetlen
- st
->cipherblk
);
1188 st
->pktin
->encrypted_len
= st
->packetlen
;
1194 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, st
->pktin
->data
, st
->len
+ 4,
1195 st
->incoming_sequence
)) {
1196 bombout(("Incorrect MAC received on packet"));
1197 ssh_free_packet(st
->pktin
);
1201 st
->pktin
->sequence
= st
->incoming_sequence
++;
1204 * Decompress packet payload.
1207 unsigned char *newpayload
;
1210 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1211 st
->pktin
->data
+ 5, st
->pktin
->length
- 5,
1212 &newpayload
, &newlen
)) {
1213 if (st
->pktin
->maxlen
< newlen
+ 5) {
1214 st
->pktin
->maxlen
= newlen
+ 5;
1215 st
->pktin
->data
= sresize(st
->pktin
->data
,
1216 st
->pktin
->maxlen
+ APIEXTRA
,
1219 st
->pktin
->length
= 5 + newlen
;
1220 memcpy(st
->pktin
->data
+ 5, newpayload
, newlen
);
1225 st
->pktin
->savedpos
= 6;
1226 st
->pktin
->body
= st
->pktin
->data
;
1227 st
->pktin
->type
= st
->pktin
->data
[5];
1230 * Log incoming packet, possibly omitting sensitive fields.
1234 struct logblank_t blank
;
1235 if (ssh
->cfg
.logomitdata
) {
1236 int do_blank
= FALSE
, blank_prefix
= 0;
1237 /* "Session data" packets - omit the data field */
1238 if (st
->pktin
->type
== SSH2_MSG_CHANNEL_DATA
) {
1239 do_blank
= TRUE
; blank_prefix
= 4;
1240 } else if (st
->pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1241 do_blank
= TRUE
; blank_prefix
= 8;
1244 blank
.offset
= blank_prefix
;
1245 blank
.len
= (st
->pktin
->length
-6) - blank_prefix
;
1246 blank
.type
= PKTLOG_OMIT
;
1250 log_packet(ssh
->logctx
, PKT_INCOMING
, st
->pktin
->type
,
1251 ssh2_pkt_type(ssh
->pkt_ctx
, st
->pktin
->type
),
1252 st
->pktin
->data
+6, st
->pktin
->length
-6,
1256 crFinish(st
->pktin
);
1259 static void ssh1_pktout_size(struct Packet
*pkt
, int len
)
1263 len
+= 5; /* type and CRC */
1264 pad
= 8 - (len
% 8);
1267 pkt
->length
= len
- 5;
1268 if (pkt
->maxlen
< biglen
) {
1269 pkt
->maxlen
= biglen
;
1270 pkt
->data
= sresize(pkt
->data
, biglen
+ 4 + APIEXTRA
, unsigned char);
1272 pkt
->body
= pkt
->data
+ 4 + pad
+ 1;
1275 static struct Packet
*s_wrpkt_start(int type
, int len
)
1277 struct Packet
*pkt
= ssh_new_packet();
1278 ssh1_pktout_size(pkt
, len
);
1280 /* Initialise log omission state */
1286 static int s_wrpkt_prepare(Ssh ssh
, struct Packet
*pkt
)
1292 * XXX various versions of SC (including 8.8.4) screw up the
1293 * register allocation in this function and use the same register
1294 * (D6) for len and as a temporary, with predictable results. The
1295 * following sledgehammer prevents this.
1301 pkt
->body
[-1] = pkt
->type
;
1304 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->type
,
1305 ssh1_pkt_type(pkt
->type
),
1306 pkt
->body
, pkt
->length
,
1307 pkt
->nblanks
, pkt
->blanks
);
1308 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1311 if (ssh
->v1_compressing
) {
1312 unsigned char *compblk
;
1314 zlib_compress_block(ssh
->cs_comp_ctx
,
1315 pkt
->body
- 1, pkt
->length
+ 1,
1316 &compblk
, &complen
);
1317 ssh1_pktout_size(pkt
, complen
- 1);
1318 memcpy(pkt
->body
- 1, compblk
, complen
);
1322 len
= pkt
->length
+ 5; /* type and CRC */
1323 pad
= 8 - (len
% 8);
1326 for (i
= 0; i
< pad
; i
++)
1327 pkt
->data
[i
+ 4] = random_byte();
1328 crc
= crc32_compute(pkt
->data
+ 4, biglen
- 4);
1329 PUT_32BIT(pkt
->data
+ biglen
, crc
);
1330 PUT_32BIT(pkt
->data
, len
);
1333 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, pkt
->data
+ 4, biglen
);
1338 static void s_wrpkt(Ssh ssh
, struct Packet
*pkt
)
1341 len
= s_wrpkt_prepare(ssh
, pkt
);
1342 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1343 if (backlog
> SSH_MAX_BACKLOG
)
1344 ssh_throttle_all(ssh
, 1, backlog
);
1347 static void s_wrpkt_defer(Ssh ssh
, struct Packet
*pkt
)
1350 len
= s_wrpkt_prepare(ssh
, pkt
);
1351 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1352 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1353 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1357 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1358 ssh
->deferred_len
+= len
;
1362 * Construct a packet with the specified contents.
1364 static struct Packet
*construct_packet(Ssh ssh
, int pkttype
,
1365 va_list ap1
, va_list ap2
)
1367 unsigned char *p
, *argp
, argchar
;
1368 unsigned long argint
;
1369 int pktlen
, argtype
, arglen
;
1374 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1377 (void) va_arg(ap1
, int);
1381 (void) va_arg(ap1
, int);
1385 (void) va_arg(ap1
, unsigned char *);
1386 arglen
= va_arg(ap1
, int);
1390 argp
= va_arg(ap1
, unsigned char *);
1391 arglen
= strlen((char *)argp
);
1392 pktlen
+= 4 + arglen
;
1395 bn
= va_arg(ap1
, Bignum
);
1396 pktlen
+= ssh1_bignum_length(bn
);
1401 /* ignore this pass */
1408 pkt
= s_wrpkt_start(pkttype
, pktlen
);
1411 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1412 int offset
= p
- pkt
->body
, len
= 0;
1414 /* Actual fields in the packet */
1416 argint
= va_arg(ap2
, int);
1417 PUT_32BIT(p
, argint
);
1421 argchar
= (unsigned char) va_arg(ap2
, int);
1426 argp
= va_arg(ap2
, unsigned char *);
1427 arglen
= va_arg(ap2
, int);
1428 memcpy(p
, argp
, arglen
);
1432 argp
= va_arg(ap2
, unsigned char *);
1433 arglen
= strlen((char *)argp
);
1434 PUT_32BIT(p
, arglen
);
1435 memcpy(p
+ 4, argp
, arglen
);
1439 bn
= va_arg(ap2
, Bignum
);
1440 len
= ssh1_write_bignum(p
, bn
);
1442 /* Tokens for modifications to packet logging */
1444 dont_log_password(ssh
, pkt
, PKTLOG_BLANK
);
1447 dont_log_data(ssh
, pkt
, PKTLOG_OMIT
);
1450 end_log_omission(ssh
, pkt
);
1454 /* Deal with logfile omission, if required. */
1455 if (len
&& (pkt
->logmode
!= PKTLOG_EMIT
)) {
1457 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
,
1459 pkt
->blanks
[pkt
->nblanks
-1].offset
= offset
;
1460 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1461 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1468 static void send_packet(Ssh ssh
, int pkttype
, ...)
1472 va_start(ap1
, pkttype
);
1473 va_start(ap2
, pkttype
);
1474 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1478 ssh_free_packet(pkt
);
1481 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1485 va_start(ap1
, pkttype
);
1486 va_start(ap2
, pkttype
);
1487 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1490 s_wrpkt_defer(ssh
, pkt
);
1491 ssh_free_packet(pkt
);
1494 static int ssh_versioncmp(char *a
, char *b
)
1497 unsigned long av
, bv
;
1499 av
= strtoul(a
, &ae
, 10);
1500 bv
= strtoul(b
, &be
, 10);
1502 return (av
< bv ?
-1 : +1);
1507 av
= strtoul(ae
, &ae
, 10);
1508 bv
= strtoul(be
, &be
, 10);
1510 return (av
< bv ?
-1 : +1);
1515 * Utility routines for putting an SSH-protocol `string' and
1516 * `uint32' into a SHA state.
1519 static void sha_string(SHA_State
* s
, void *str
, int len
)
1521 unsigned char lenblk
[4];
1522 PUT_32BIT(lenblk
, len
);
1523 SHA_Bytes(s
, lenblk
, 4);
1524 SHA_Bytes(s
, str
, len
);
1527 static void sha_uint32(SHA_State
* s
, unsigned i
)
1529 unsigned char intblk
[4];
1530 PUT_32BIT(intblk
, i
);
1531 SHA_Bytes(s
, intblk
, 4);
1535 * SSH2 packet construction functions.
1537 static void ssh2_pkt_ensure(struct Packet
*pkt
, int length
)
1539 if (pkt
->maxlen
< length
) {
1540 pkt
->maxlen
= length
+ 256;
1541 pkt
->data
= sresize(pkt
->data
, pkt
->maxlen
+ APIEXTRA
, unsigned char);
1544 static void ssh2_pkt_adddata(struct Packet
*pkt
, void *data
, int len
)
1546 if (pkt
->logmode
!= PKTLOG_EMIT
) {
1548 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
, struct logblank_t
);
1549 pkt
->blanks
[pkt
->nblanks
-1].offset
= pkt
->length
- 6;
1550 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1551 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1554 ssh2_pkt_ensure(pkt
, pkt
->length
);
1555 memcpy(pkt
->data
+ pkt
->length
- len
, data
, len
);
1557 static void ssh2_pkt_addbyte(struct Packet
*pkt
, unsigned char byte
)
1559 ssh2_pkt_adddata(pkt
, &byte
, 1);
1561 static struct Packet
*ssh2_pkt_init(int pkt_type
)
1563 struct Packet
*pkt
= ssh_new_packet();
1565 ssh2_pkt_addbyte(pkt
, (unsigned char) pkt_type
);
1568 static void ssh2_pkt_addbool(struct Packet
*pkt
, unsigned char value
)
1570 ssh2_pkt_adddata(pkt
, &value
, 1);
1572 static void ssh2_pkt_adduint32(struct Packet
*pkt
, unsigned long value
)
1575 PUT_32BIT(x
, value
);
1576 ssh2_pkt_adddata(pkt
, x
, 4);
1578 static void ssh2_pkt_addstring_start(struct Packet
*pkt
)
1580 ssh2_pkt_adduint32(pkt
, 0);
1581 pkt
->savedpos
= pkt
->length
;
1583 static void ssh2_pkt_addstring_str(struct Packet
*pkt
, char *data
)
1585 ssh2_pkt_adddata(pkt
, data
, strlen(data
));
1586 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1588 static void ssh2_pkt_addstring_data(struct Packet
*pkt
, char *data
, int len
)
1590 ssh2_pkt_adddata(pkt
, data
, len
);
1591 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1593 static void ssh2_pkt_addstring(struct Packet
*pkt
, char *data
)
1595 ssh2_pkt_addstring_start(pkt
);
1596 ssh2_pkt_addstring_str(pkt
, data
);
1598 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1601 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1602 p
= snewn(n
+ 1, unsigned char);
1604 fatalbox("out of memory");
1606 for (i
= 1; i
<= n
; i
++)
1607 p
[i
] = bignum_byte(b
, n
- i
);
1609 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1611 memmove(p
, p
+ i
, n
+ 1 - i
);
1615 static void ssh2_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1619 p
= ssh2_mpint_fmt(b
, &len
);
1620 ssh2_pkt_addstring_start(pkt
);
1621 ssh2_pkt_addstring_data(pkt
, (char *)p
, len
);
1626 * Construct an SSH2 final-form packet: compress it, encrypt it,
1627 * put the MAC on it. Final packet, ready to be sent, is stored in
1628 * pkt->data. Total length is returned.
1630 static int ssh2_pkt_construct(Ssh ssh
, struct Packet
*pkt
)
1632 int cipherblk
, maclen
, padding
, i
;
1635 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[5],
1636 ssh2_pkt_type(ssh
->pkt_ctx
, pkt
->data
[5]),
1637 pkt
->data
+ 6, pkt
->length
- 6,
1638 pkt
->nblanks
, pkt
->blanks
);
1639 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1643 * Compress packet payload.
1646 unsigned char *newpayload
;
1649 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, pkt
->data
+ 5,
1651 &newpayload
, &newlen
)) {
1653 ssh2_pkt_adddata(pkt
, newpayload
, newlen
);
1659 * Add padding. At least four bytes, and must also bring total
1660 * length (minus MAC) up to a multiple of the block size.
1662 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1663 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1666 (cipherblk
- (pkt
->length
+ padding
) % cipherblk
) % cipherblk
;
1667 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1668 ssh2_pkt_ensure(pkt
, pkt
->length
+ padding
+ maclen
);
1669 pkt
->data
[4] = padding
;
1670 for (i
= 0; i
< padding
; i
++)
1671 pkt
->data
[pkt
->length
+ i
] = random_byte();
1672 PUT_32BIT(pkt
->data
, pkt
->length
+ padding
- 4);
1674 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, pkt
->data
,
1675 pkt
->length
+ padding
,
1676 ssh
->v2_outgoing_sequence
);
1677 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1680 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1681 pkt
->data
, pkt
->length
+ padding
);
1683 pkt
->encrypted_len
= pkt
->length
+ padding
;
1685 /* Ready-to-send packet starts at pkt->data. We return length. */
1686 return pkt
->length
+ padding
+ maclen
;
1690 * Routines called from the main SSH code to send packets. There
1691 * are quite a few of these, because we have two separate
1692 * mechanisms for delaying the sending of packets:
1694 * - In order to send an IGNORE message and a password message in
1695 * a single fixed-length blob, we require the ability to
1696 * concatenate the encrypted forms of those two packets _into_ a
1697 * single blob and then pass it to our <network.h> transport
1698 * layer in one go. Hence, there's a deferment mechanism which
1699 * works after packet encryption.
1701 * - In order to avoid sending any connection-layer messages
1702 * during repeat key exchange, we have to queue up any such
1703 * outgoing messages _before_ they are encrypted (and in
1704 * particular before they're allocated sequence numbers), and
1705 * then send them once we've finished.
1707 * I call these mechanisms `defer' and `queue' respectively, so as
1708 * to distinguish them reasonably easily.
1710 * The functions send_noqueue() and defer_noqueue() free the packet
1711 * structure they are passed. Every outgoing packet goes through
1712 * precisely one of these functions in its life; packets passed to
1713 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1714 * these or get queued, and then when the queue is later emptied
1715 * the packets are all passed to defer_noqueue().
1719 * Send an SSH2 packet immediately, without queuing or deferring.
1721 static void ssh2_pkt_send_noqueue(Ssh ssh
, struct Packet
*pkt
)
1725 len
= ssh2_pkt_construct(ssh
, pkt
);
1726 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1727 if (backlog
> SSH_MAX_BACKLOG
)
1728 ssh_throttle_all(ssh
, 1, backlog
);
1730 ssh
->outgoing_data_size
+= pkt
->encrypted_len
;
1731 if (!ssh
->kex_in_progress
&&
1732 ssh
->max_data_size
!= 0 &&
1733 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1734 do_ssh2_transport(ssh
, "Initiating key re-exchange "
1735 "(too much data sent)", -1, NULL
);
1737 ssh_free_packet(pkt
);
1741 * Defer an SSH2 packet.
1743 static void ssh2_pkt_defer_noqueue(Ssh ssh
, struct Packet
*pkt
)
1745 int len
= ssh2_pkt_construct(ssh
, pkt
);
1746 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1747 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1748 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1752 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1753 ssh
->deferred_len
+= len
;
1754 ssh
->deferred_data_size
+= pkt
->encrypted_len
;
1755 ssh_free_packet(pkt
);
1759 * Queue an SSH2 packet.
1761 static void ssh2_pkt_queue(Ssh ssh
, struct Packet
*pkt
)
1763 assert(ssh
->queueing
);
1765 if (ssh
->queuelen
>= ssh
->queuesize
) {
1766 ssh
->queuesize
= ssh
->queuelen
+ 32;
1767 ssh
->queue
= sresize(ssh
->queue
, ssh
->queuesize
, struct Packet
*);
1770 ssh
->queue
[ssh
->queuelen
++] = pkt
;
1774 * Either queue or send a packet, depending on whether queueing is
1777 static void ssh2_pkt_send(Ssh ssh
, struct Packet
*pkt
)
1780 ssh2_pkt_queue(ssh
, pkt
);
1782 ssh2_pkt_send_noqueue(ssh
, pkt
);
1786 * Either queue or defer a packet, depending on whether queueing is
1789 static void ssh2_pkt_defer(Ssh ssh
, struct Packet
*pkt
)
1792 ssh2_pkt_queue(ssh
, pkt
);
1794 ssh2_pkt_defer_noqueue(ssh
, pkt
);
1798 * Send the whole deferred data block constructed by
1799 * ssh2_pkt_defer() or SSH1's defer_packet().
1801 * The expected use of the defer mechanism is that you call
1802 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1803 * not currently queueing, this simply sets up deferred_send_data
1804 * and then sends it. If we _are_ currently queueing, the calls to
1805 * ssh2_pkt_defer() put the deferred packets on to the queue
1806 * instead, and therefore ssh_pkt_defersend() has no deferred data
1807 * to send. Hence, there's no need to make it conditional on
1810 static void ssh_pkt_defersend(Ssh ssh
)
1813 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1815 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1816 sfree(ssh
->deferred_send_data
);
1817 ssh
->deferred_send_data
= NULL
;
1818 if (backlog
> SSH_MAX_BACKLOG
)
1819 ssh_throttle_all(ssh
, 1, backlog
);
1821 ssh
->outgoing_data_size
+= ssh
->deferred_data_size
;
1822 if (!ssh
->kex_in_progress
&&
1823 ssh
->max_data_size
!= 0 &&
1824 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1825 do_ssh2_transport(ssh
, "Initiating key re-exchange "
1826 "(too much data sent)", -1, NULL
);
1827 ssh
->deferred_data_size
= 0;
1831 * Send all queued SSH2 packets. We send them by means of
1832 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1833 * packets that needed to be lumped together.
1835 static void ssh2_pkt_queuesend(Ssh ssh
)
1839 assert(!ssh
->queueing
);
1841 for (i
= 0; i
< ssh
->queuelen
; i
++)
1842 ssh2_pkt_defer_noqueue(ssh
, ssh
->queue
[i
]);
1845 ssh_pkt_defersend(ssh
);
1849 void bndebug(char *string
, Bignum b
)
1853 p
= ssh2_mpint_fmt(b
, &len
);
1854 debug(("%s", string
));
1855 for (i
= 0; i
< len
; i
++)
1856 debug((" %02x", p
[i
]));
1862 static void sha_mpint(SHA_State
* s
, Bignum b
)
1866 p
= ssh2_mpint_fmt(b
, &len
);
1867 sha_string(s
, p
, len
);
1872 * Packet decode functions for both SSH1 and SSH2.
1874 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
)
1876 unsigned long value
;
1877 if (pkt
->length
- pkt
->savedpos
< 4)
1878 return 0; /* arrgh, no way to decline (FIXME?) */
1879 value
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1883 static int ssh2_pkt_getbool(struct Packet
*pkt
)
1885 unsigned long value
;
1886 if (pkt
->length
- pkt
->savedpos
< 1)
1887 return 0; /* arrgh, no way to decline (FIXME?) */
1888 value
= pkt
->body
[pkt
->savedpos
] != 0;
1892 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
)
1897 if (pkt
->length
- pkt
->savedpos
< 4)
1899 len
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1904 if (pkt
->length
- pkt
->savedpos
< *length
)
1906 *p
= (char *)(pkt
->body
+ pkt
->savedpos
);
1907 pkt
->savedpos
+= *length
;
1909 static void *ssh_pkt_getdata(struct Packet
*pkt
, int length
)
1911 if (pkt
->length
- pkt
->savedpos
< length
)
1913 pkt
->savedpos
+= length
;
1914 return pkt
->body
+ (pkt
->savedpos
- length
);
1916 static int ssh1_pkt_getrsakey(struct Packet
*pkt
, struct RSAKey
*key
,
1917 unsigned char **keystr
)
1921 j
= makekey(pkt
->body
+ pkt
->savedpos
,
1922 pkt
->length
- pkt
->savedpos
,
1929 assert(pkt
->savedpos
< pkt
->length
);
1933 static Bignum
ssh1_pkt_getmp(struct Packet
*pkt
)
1938 j
= ssh1_read_bignum(pkt
->body
+ pkt
->savedpos
,
1939 pkt
->length
- pkt
->savedpos
, &b
);
1947 static Bignum
ssh2_pkt_getmp(struct Packet
*pkt
)
1953 ssh_pkt_getstring(pkt
, &p
, &length
);
1958 b
= bignum_from_bytes((unsigned char *)p
, length
);
1963 * Helper function to add an SSH2 signature blob to a packet.
1964 * Expects to be shown the public key blob as well as the signature
1965 * blob. Normally works just like ssh2_pkt_addstring, but will
1966 * fiddle with the signature packet if necessary for
1967 * BUG_SSH2_RSA_PADDING.
1969 static void ssh2_add_sigblob(Ssh ssh
, struct Packet
*pkt
,
1970 void *pkblob_v
, int pkblob_len
,
1971 void *sigblob_v
, int sigblob_len
)
1973 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1974 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1976 /* dmemdump(pkblob, pkblob_len); */
1977 /* dmemdump(sigblob, sigblob_len); */
1980 * See if this is in fact an ssh-rsa signature and a buggy
1981 * server; otherwise we can just do this the easy way.
1983 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1984 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1985 int pos
, len
, siglen
;
1988 * Find the byte length of the modulus.
1991 pos
= 4+7; /* skip over "ssh-rsa" */
1992 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1993 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
1994 pos
+= 4; /* find modulus itself */
1995 while (len
> 0 && pkblob
[pos
] == 0)
1997 /* debug(("modulus length is %d\n", len)); */
2000 * Now find the signature integer.
2002 pos
= 4+7; /* skip over "ssh-rsa" */
2003 siglen
= GET_32BIT(sigblob
+pos
);
2004 /* debug(("signature length is %d\n", siglen)); */
2006 if (len
!= siglen
) {
2007 unsigned char newlen
[4];
2008 ssh2_pkt_addstring_start(pkt
);
2009 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, pos
);
2010 /* dmemdump(sigblob, pos); */
2011 pos
+= 4; /* point to start of actual sig */
2012 PUT_32BIT(newlen
, len
);
2013 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 4);
2014 /* dmemdump(newlen, 4); */
2016 while (len
-- > siglen
) {
2017 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 1);
2018 /* dmemdump(newlen, 1); */
2020 ssh2_pkt_addstring_data(pkt
, (char *)(sigblob
+pos
), siglen
);
2021 /* dmemdump(sigblob+pos, siglen); */
2025 /* Otherwise fall through and do it the easy way. */
2028 ssh2_pkt_addstring_start(pkt
);
2029 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, sigblob_len
);
2033 * Examine the remote side's version string and compare it against
2034 * a list of known buggy implementations.
2036 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
2038 char *imp
; /* pointer to implementation part */
2040 imp
+= strcspn(imp
, "-");
2042 imp
+= strcspn(imp
, "-");
2045 ssh
->remote_bugs
= 0;
2047 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
2048 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
2049 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
2050 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
2051 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
2052 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
2054 * These versions don't support SSH1_MSG_IGNORE, so we have
2055 * to use a different defence against password length
2058 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
2059 logevent("We believe remote version has SSH1 ignore bug");
2062 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
2063 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
2064 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
2066 * These versions need a plain password sent; they can't
2067 * handle having a null and a random length of data after
2070 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
2071 logevent("We believe remote version needs a plain SSH1 password");
2074 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
2075 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
2076 (!strcmp(imp
, "Cisco-1.25")))) {
2078 * These versions apparently have no clue whatever about
2079 * RSA authentication and will panic and die if they see
2080 * an AUTH_RSA message.
2082 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
2083 logevent("We believe remote version can't handle RSA authentication");
2086 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
2087 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
2088 !wc_match("* VShell", imp
) &&
2089 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
2090 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
2091 wc_match("2.1 *", imp
)))) {
2093 * These versions have the HMAC bug.
2095 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
2096 logevent("We believe remote version has SSH2 HMAC bug");
2099 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2100 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2101 !wc_match("* VShell", imp
) &&
2102 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2104 * These versions have the key-derivation bug (failing to
2105 * include the literal shared secret in the hashes that
2106 * generate the keys).
2108 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2109 logevent("We believe remote version has SSH2 key-derivation bug");
2112 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2113 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2114 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2115 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2117 * These versions have the SSH2 RSA padding bug.
2119 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2120 logevent("We believe remote version has SSH2 RSA padding bug");
2123 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2124 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2125 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2127 * These versions have the SSH2 session-ID bug in
2128 * public-key authentication.
2130 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2131 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2136 * The `software version' part of an SSH version string is required
2137 * to contain no spaces or minus signs.
2139 static void ssh_fix_verstring(char *str
)
2141 /* Eat "SSH-<protoversion>-". */
2142 assert(*str
== 'S'); str
++;
2143 assert(*str
== 'S'); str
++;
2144 assert(*str
== 'H'); str
++;
2145 assert(*str
== '-'); str
++;
2146 while (*str
&& *str
!= '-') str
++;
2147 assert(*str
== '-'); str
++;
2149 /* Convert minus signs and spaces in the remaining string into
2152 if (*str
== '-' || *str
== ' ')
2158 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2160 struct do_ssh_init_state
{
2168 crState(do_ssh_init_state
);
2170 crBegin(ssh
->do_ssh_init_crstate
);
2172 /* Search for the string "SSH-" in the input. */
2175 static const int transS
[] = { 1, 2, 2, 1 };
2176 static const int transH
[] = { 0, 0, 3, 0 };
2177 static const int transminus
[] = { 0, 0, 0, -1 };
2179 s
->i
= transS
[s
->i
];
2181 s
->i
= transH
[s
->i
];
2183 s
->i
= transminus
[s
->i
];
2188 crReturn(1); /* get another character */
2192 s
->vstring
= snewn(s
->vstrsize
, char);
2193 strcpy(s
->vstring
, "SSH-");
2197 crReturn(1); /* get another char */
2198 if (s
->vslen
>= s
->vstrsize
- 1) {
2200 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2202 s
->vstring
[s
->vslen
++] = c
;
2205 s
->version
[s
->i
] = '\0';
2207 } else if (s
->i
< sizeof(s
->version
) - 1)
2208 s
->version
[s
->i
++] = c
;
2209 } else if (c
== '\012')
2213 ssh
->agentfwd_enabled
= FALSE
;
2214 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2216 s
->vstring
[s
->vslen
] = 0;
2217 s
->vstring
[strcspn(s
->vstring
, "\015\012")] = '\0';/* remove EOL chars */
2220 vlog
= snewn(20 + s
->vslen
, char);
2221 sprintf(vlog
, "Server version: %s", s
->vstring
);
2225 ssh_detect_bugs(ssh
, s
->vstring
);
2228 * Decide which SSH protocol version to support.
2231 /* Anything strictly below "2.0" means protocol 1 is supported. */
2232 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2233 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2234 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2236 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2237 bombout(("SSH protocol version 1 required by user but not provided by server"));
2240 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2241 bombout(("SSH protocol version 2 required by user but not provided by server"));
2248 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2250 * Construct a v2 version string.
2252 verstring
= dupprintf("SSH-2.0-%s\015\012", sshver
);
2256 * Construct a v1 version string.
2258 verstring
= dupprintf("SSH-%s-%s\012",
2259 (ssh_versioncmp(s
->version
, "1.5") <= 0 ?
2260 s
->version
: "1.5"),
2265 ssh_fix_verstring(verstring
);
2267 if (ssh
->version
== 2) {
2269 * Hash our version string and their version string.
2271 SHA_Init(&ssh
->exhashbase
);
2272 sha_string(&ssh
->exhashbase
, verstring
,
2273 strcspn(verstring
, "\015\012"));
2274 sha_string(&ssh
->exhashbase
, s
->vstring
,
2275 strcspn(s
->vstring
, "\015\012"));
2278 * Initialise SSHv2 protocol.
2280 ssh
->protocol
= ssh2_protocol
;
2281 ssh2_protocol_setup(ssh
);
2282 ssh
->s_rdpkt
= ssh2_rdpkt
;
2285 * Initialise SSHv1 protocol.
2287 ssh
->protocol
= ssh1_protocol
;
2288 ssh1_protocol_setup(ssh
);
2289 ssh
->s_rdpkt
= ssh1_rdpkt
;
2291 logeventf(ssh
, "We claim version: %.*s",
2292 strcspn(verstring
, "\015\012"), verstring
);
2293 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2297 logeventf(ssh
, "Using SSH protocol version %d", ssh
->version
);
2299 update_specials_menu(ssh
->frontend
);
2300 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2301 ssh
->pinger
= pinger_new(&ssh
->cfg
, &ssh_backend
, ssh
);
2308 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2310 crBegin(ssh
->ssh_gotdata_crstate
);
2313 * To begin with, feed the characters one by one to the
2314 * protocol initialisation / selection function do_ssh_init().
2315 * When that returns 0, we're done with the initial greeting
2316 * exchange and can move on to packet discipline.
2319 int ret
; /* need not be kept across crReturn */
2321 crReturnV
; /* more data please */
2322 ret
= do_ssh_init(ssh
, *data
);
2330 * We emerge from that loop when the initial negotiation is
2331 * over and we have selected an s_rdpkt function. Now pass
2332 * everything to s_rdpkt, and then pass the resulting packets
2333 * to the proper protocol handler.
2338 while (datalen
> 0) {
2339 struct Packet
*pktin
= ssh
->s_rdpkt(ssh
, &data
, &datalen
);
2341 ssh
->protocol(ssh
, NULL
, 0, pktin
);
2342 ssh_free_packet(pktin
);
2344 if (ssh
->state
== SSH_STATE_CLOSED
)
2352 static void ssh_do_close(Ssh ssh
)
2355 struct ssh_channel
*c
;
2357 ssh
->state
= SSH_STATE_CLOSED
;
2361 notify_remote_exit(ssh
->frontend
);
2364 * Now we must shut down any port and X forwardings going
2365 * through this connection.
2367 if (ssh
->channels
) {
2368 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2371 x11_close(c
->u
.x11
.s
);
2374 pfd_close(c
->u
.pfd
.s
);
2377 del234(ssh
->channels
, c
);
2378 if (ssh
->version
== 2)
2379 bufchain_clear(&c
->v
.v2
.outbuffer
);
2385 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2388 Ssh ssh
= (Ssh
) plug
;
2391 /* A socket error has occurred. */
2392 logevent(error_msg
);
2393 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2395 /* Otherwise, the remote side closed the connection normally. */
2400 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2402 Ssh ssh
= (Ssh
) plug
;
2403 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2404 if (ssh
->state
== SSH_STATE_CLOSED
) {
2411 static void ssh_sent(Plug plug
, int bufsize
)
2413 Ssh ssh
= (Ssh
) plug
;
2415 * If the send backlog on the SSH socket itself clears, we
2416 * should unthrottle the whole world if it was throttled.
2418 if (bufsize
< SSH_MAX_BACKLOG
)
2419 ssh_throttle_all(ssh
, 0, bufsize
);
2423 * Connect to specified host and port.
2424 * Returns an error message, or NULL on success.
2425 * Also places the canonical host name into `realhost'. It must be
2426 * freed by the caller.
2428 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2429 char **realhost
, int nodelay
, int keepalive
)
2431 static const struct plug_function_table fn_table
= {
2441 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2442 if (!ssh
->savedhost
)
2443 fatalbox("Out of memory");
2444 strcpy(ssh
->savedhost
, host
);
2447 port
= 22; /* default ssh port */
2448 ssh
->savedport
= port
;
2453 logeventf(ssh
, "Looking up host \"%s\"%s", host
,
2454 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV4 ?
" (IPv4)" :
2455 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV6 ?
" (IPv6)" : "")));
2456 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
,
2457 ssh
->cfg
.addressfamily
);
2458 if ((err
= sk_addr_error(addr
)) != NULL
) {
2468 sk_getaddr(addr
, addrbuf
, 100);
2469 logeventf(ssh
, "Connecting to %s port %d", addrbuf
, port
);
2471 ssh
->fn
= &fn_table
;
2472 ssh
->s
= new_connection(addr
, *realhost
, port
,
2473 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2474 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2476 notify_remote_exit(ssh
->frontend
);
2484 * Throttle or unthrottle the SSH connection.
2486 static void ssh1_throttle(Ssh ssh
, int adjust
)
2488 int old_count
= ssh
->v1_throttle_count
;
2489 ssh
->v1_throttle_count
+= adjust
;
2490 assert(ssh
->v1_throttle_count
>= 0);
2491 if (ssh
->v1_throttle_count
&& !old_count
) {
2492 sk_set_frozen(ssh
->s
, 1);
2493 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2494 sk_set_frozen(ssh
->s
, 0);
2499 * Throttle or unthrottle _all_ local data streams (for when sends
2500 * on the SSH connection itself back up).
2502 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2505 struct ssh_channel
*c
;
2507 if (enable
== ssh
->throttled_all
)
2509 ssh
->throttled_all
= enable
;
2510 ssh
->overall_bufsize
= bufsize
;
2513 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2515 case CHAN_MAINSESSION
:
2517 * This is treated separately, outside the switch.
2521 x11_override_throttle(c
->u
.x11
.s
, enable
);
2524 /* Agent channels require no buffer management. */
2527 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2534 * Username and password input, abstracted off into routines
2535 * reusable in several places - even between SSH1 and SSH2.
2538 /* Set up a username or password input loop on a given buffer. */
2539 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2541 ssh
->userpass_input_buffer
= buffer
;
2542 ssh
->userpass_input_buflen
= buflen
;
2543 ssh
->userpass_input_bufpos
= 0;
2544 ssh
->userpass_input_echo
= echo
;
2548 * Process some terminal data in the course of username/password
2549 * input. Returns >0 for success (line of input returned in
2550 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2551 * for inconclusive (keep waiting for more input please).
2553 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2558 switch (c
= *in
++) {
2561 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2562 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2567 if (ssh
->userpass_input_bufpos
> 0) {
2568 if (ssh
->userpass_input_echo
)
2569 c_write_str(ssh
, "\b \b");
2570 ssh
->userpass_input_bufpos
--;
2575 while (ssh
->userpass_input_bufpos
> 0) {
2576 if (ssh
->userpass_input_echo
)
2577 c_write_str(ssh
, "\b \b");
2578 ssh
->userpass_input_bufpos
--;
2587 * This simplistic check for printability is disabled
2588 * when we're doing password input, because some people
2589 * have control characters in their passwords.o
2591 if ((!ssh
->userpass_input_echo
||
2592 (c
>= ' ' && c
<= '~') ||
2593 ((unsigned char) c
>= 160))
2594 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2595 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2596 if (ssh
->userpass_input_echo
)
2597 c_write(ssh
, &c
, 1);
2605 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2607 Ssh ssh
= (Ssh
) sshv
;
2609 ssh
->agent_response
= reply
;
2610 ssh
->agent_response_len
= replylen
;
2612 if (ssh
->version
== 1)
2613 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2615 do_ssh2_authconn(ssh
, NULL
, -1, NULL
);
2618 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2620 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2622 void *sentreply
= reply
;
2625 /* Fake SSH_AGENT_FAILURE. */
2626 sentreply
= "\0\0\0\1\5";
2629 if (ssh
->version
== 2) {
2630 ssh2_add_channel_data(c
, sentreply
, replylen
);
2633 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2634 PKT_INT
, c
->remoteid
,
2637 PKT_DATA
, sentreply
, replylen
,
2646 * Handle the key exchange and user authentication phases.
2648 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
2649 struct Packet
*pktin
)
2652 unsigned char cookie
[8], *ptr
;
2653 struct RSAKey servkey
, hostkey
;
2654 struct MD5Context md5c
;
2655 struct do_ssh1_login_state
{
2657 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2658 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2659 int tried_publickey
, tried_agent
;
2660 int tis_auth_refused
, ccard_auth_refused
;
2661 unsigned char session_id
[16];
2664 void *publickey_blob
;
2665 int publickey_bloblen
;
2671 unsigned char request
[5], *response
, *p
;
2680 crState(do_ssh1_login_state
);
2682 crBegin(ssh
->do_ssh1_login_crstate
);
2687 if (pktin
->type
!= SSH1_SMSG_PUBLIC_KEY
) {
2688 bombout(("Public key packet not received"));
2692 logevent("Received public keys");
2694 ptr
= ssh_pkt_getdata(pktin
, 8);
2696 bombout(("SSH1 public key packet stopped before random cookie"));
2699 memcpy(cookie
, ptr
, 8);
2701 if (!ssh1_pkt_getrsakey(pktin
, &servkey
, &s
->keystr1
) ||
2702 !ssh1_pkt_getrsakey(pktin
, &hostkey
, &s
->keystr2
)) {
2703 bombout(("Failed to read SSH1 public keys from public key packet"));
2708 * Log the host key fingerprint.
2712 logevent("Host key fingerprint is:");
2713 strcpy(logmsg
, " ");
2714 hostkey
.comment
= NULL
;
2715 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2716 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2720 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(pktin
);
2721 s
->supported_ciphers_mask
= ssh_pkt_getuint32(pktin
);
2722 s
->supported_auths_mask
= ssh_pkt_getuint32(pktin
);
2724 ssh
->v1_local_protoflags
=
2725 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2726 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2729 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2730 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2731 MD5Update(&md5c
, cookie
, 8);
2732 MD5Final(s
->session_id
, &md5c
);
2734 for (i
= 0; i
< 32; i
++)
2735 ssh
->session_key
[i
] = random_byte();
2738 * Verify that the `bits' and `bytes' parameters match.
2740 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
2741 servkey
.bits
> servkey
.bytes
* 8) {
2742 bombout(("SSH1 public keys were badly formatted"));
2746 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2748 s
->rsabuf
= snewn(s
->len
, unsigned char);
2750 fatalbox("Out of memory");
2753 * Verify the host key.
2757 * First format the key into a string.
2759 int len
= rsastr_len(&hostkey
);
2760 char fingerprint
[100];
2761 char *keystr
= snewn(len
, char);
2763 fatalbox("Out of memory");
2764 rsastr_fmt(keystr
, &hostkey
);
2765 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2766 verify_ssh_host_key(ssh
->frontend
,
2767 ssh
->savedhost
, ssh
->savedport
, "rsa", keystr
,
2772 for (i
= 0; i
< 32; i
++) {
2773 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2775 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2778 if (hostkey
.bytes
> servkey
.bytes
) {
2779 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
2781 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2783 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2785 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2788 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2792 logevent("Encrypted session key");
2795 int cipher_chosen
= 0, warn
= 0;
2796 char *cipher_string
= NULL
;
2798 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2799 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
2800 if (next_cipher
== CIPHER_WARN
) {
2801 /* If/when we choose a cipher, warn about it */
2803 } else if (next_cipher
== CIPHER_AES
) {
2804 /* XXX Probably don't need to mention this. */
2805 logevent("AES not supported in SSH1, skipping");
2807 switch (next_cipher
) {
2808 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2809 cipher_string
= "3DES"; break;
2810 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2811 cipher_string
= "Blowfish"; break;
2812 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2813 cipher_string
= "single-DES"; break;
2815 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2819 if (!cipher_chosen
) {
2820 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2821 bombout(("Server violates SSH 1 protocol by not "
2822 "supporting 3DES encryption"));
2824 /* shouldn't happen */
2825 bombout(("No supported ciphers found"));
2829 /* Warn about chosen cipher if necessary. */
2831 askalg(ssh
->frontend
, "cipher", cipher_string
);
2834 switch (s
->cipher_type
) {
2835 case SSH_CIPHER_3DES
:
2836 logevent("Using 3DES encryption");
2838 case SSH_CIPHER_DES
:
2839 logevent("Using single-DES encryption");
2841 case SSH_CIPHER_BLOWFISH
:
2842 logevent("Using Blowfish encryption");
2846 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
2847 PKT_CHAR
, s
->cipher_type
,
2848 PKT_DATA
, cookie
, 8,
2849 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
2850 PKT_DATA
, s
->rsabuf
, s
->len
,
2851 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
2853 logevent("Trying to enable encryption...");
2857 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2858 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
2860 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
2861 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
2862 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
2864 ssh
->crcda_ctx
= crcda_make_context();
2865 logevent("Installing CRC compensation attack detector");
2867 if (servkey
.modulus
) {
2868 sfree(servkey
.modulus
);
2869 servkey
.modulus
= NULL
;
2871 if (servkey
.exponent
) {
2872 sfree(servkey
.exponent
);
2873 servkey
.exponent
= NULL
;
2875 if (hostkey
.modulus
) {
2876 sfree(hostkey
.modulus
);
2877 hostkey
.modulus
= NULL
;
2879 if (hostkey
.exponent
) {
2880 sfree(hostkey
.exponent
);
2881 hostkey
.exponent
= NULL
;
2885 if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
2886 bombout(("Encryption not successfully enabled"));
2890 logevent("Successfully started encryption");
2894 if (!*ssh
->cfg
.username
) {
2895 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2896 if (!ssh_get_line("login as: ",
2897 s
->username
, sizeof(s
->username
), FALSE
)) {
2899 * get_line failed to get a username.
2902 logevent("No username provided. Abandoning session.");
2903 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2907 int ret
; /* need not be kept over crReturn */
2908 c_write_str(ssh
, "login as: ");
2911 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
2913 crWaitUntil(!pktin
);
2914 ret
= process_userpass_input(ssh
, in
, inlen
);
2918 c_write_str(ssh
, "\r\n");
2921 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
2922 s
->username
[sizeof(s
->username
)-1] = '\0';
2925 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
2927 char userlog
[22 + sizeof(s
->username
)];
2928 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
2930 if (flags
& FLAG_INTERACTIVE
&&
2931 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2932 strcat(userlog
, "\r\n");
2933 c_write_str(ssh
, userlog
);
2940 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2941 /* We must not attempt PK auth. Pretend we've already tried it. */
2942 s
->tried_publickey
= s
->tried_agent
= 1;
2944 s
->tried_publickey
= s
->tried_agent
= 0;
2946 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
2947 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
2948 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
2949 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
2950 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
2951 s
->publickey_blob
= NULL
;
2953 s
->publickey_blob
= NULL
;
2955 while (pktin
->type
== SSH1_SMSG_FAILURE
) {
2956 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2958 if (agent_exists() && !s
->tried_agent
) {
2960 * Attempt RSA authentication using Pageant.
2966 logevent("Pageant is running. Requesting keys.");
2968 /* Request the keys held by the agent. */
2969 PUT_32BIT(s
->request
, 1);
2970 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2971 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
2972 ssh_agent_callback
, ssh
)) {
2976 bombout(("Unexpected data from server while waiting"
2977 " for agent response"));
2980 } while (pktin
|| inlen
> 0);
2981 r
= ssh
->agent_response
;
2982 s
->responselen
= ssh
->agent_response_len
;
2984 s
->response
= (unsigned char *) r
;
2985 if (s
->response
&& s
->responselen
>= 5 &&
2986 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
2987 s
->p
= s
->response
+ 5;
2988 s
->nkeys
= GET_32BIT(s
->p
);
2992 sprintf(buf
, "Pageant has %d SSH1 keys", s
->nkeys
);
2995 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
2998 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
3001 if (s
->publickey_blob
&&
3002 !memcmp(s
->p
, s
->publickey_blob
,
3003 s
->publickey_bloblen
)) {
3004 logevent("This key matches configured key file");
3005 s
->tried_publickey
= 1;
3010 do { /* do while (0) to make breaking easy */
3011 n
= ssh1_read_bignum
3012 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3017 n
= ssh1_read_bignum
3018 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3023 if (s
->responselen
- (s
->p
-s
->response
) < 4)
3025 s
->commentlen
= GET_32BIT(s
->p
);
3027 if (s
->responselen
- (s
->p
-s
->response
) <
3030 s
->commentp
= (char *)s
->p
;
3031 s
->p
+= s
->commentlen
;
3035 logevent("Pageant key list packet was truncated");
3039 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3040 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3042 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3043 logevent("Key refused");
3046 logevent("Received RSA challenge");
3047 if ((s
->challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3048 bombout(("Server's RSA challenge was badly formatted"));
3053 char *agentreq
, *q
, *ret
;
3056 len
= 1 + 4; /* message type, bit count */
3057 len
+= ssh1_bignum_length(s
->key
.exponent
);
3058 len
+= ssh1_bignum_length(s
->key
.modulus
);
3059 len
+= ssh1_bignum_length(s
->challenge
);
3060 len
+= 16; /* session id */
3061 len
+= 4; /* response format */
3062 agentreq
= snewn(4 + len
, char);
3063 PUT_32BIT(agentreq
, len
);
3065 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
3066 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
3068 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
3069 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
3070 q
+= ssh1_write_bignum(q
, s
->challenge
);
3071 memcpy(q
, s
->session_id
, 16);
3073 PUT_32BIT(q
, 1); /* response format */
3074 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
3075 ssh_agent_callback
, ssh
)) {
3080 bombout(("Unexpected data from server"
3081 " while waiting for agent"
3085 } while (pktin
|| inlen
> 0);
3086 vret
= ssh
->agent_response
;
3087 retlen
= ssh
->agent_response_len
;
3092 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
3093 logevent("Sending Pageant's response");
3094 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3095 PKT_DATA
, ret
+ 5, 16,
3099 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
3101 ("Pageant's response accepted");
3102 if (flags
& FLAG_VERBOSE
) {
3103 c_write_str(ssh
, "Authenticated using"
3105 c_write(ssh
, s
->commentp
,
3107 c_write_str(ssh
, "\" from agent\r\n");
3112 ("Pageant's response not accepted");
3115 ("Pageant failed to answer challenge");
3119 logevent("No reply received from Pageant");
3122 freebn(s
->key
.exponent
);
3123 freebn(s
->key
.modulus
);
3124 freebn(s
->challenge
);
3133 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
3134 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
3136 if (ssh
->cfg
.try_tis_auth
&&
3137 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3138 !s
->tis_auth_refused
) {
3139 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3140 logevent("Requested TIS authentication");
3141 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3143 if (pktin
->type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3144 logevent("TIS authentication declined");
3145 if (flags
& FLAG_INTERACTIVE
)
3146 c_write_str(ssh
, "TIS authentication refused.\r\n");
3147 s
->tis_auth_refused
= 1;
3153 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3155 bombout(("TIS challenge packet was badly formed"));
3158 logevent("Received TIS challenge");
3159 if (challengelen
> sizeof(s
->prompt
) - 1)
3160 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3161 memcpy(s
->prompt
, challenge
, challengelen
);
3162 /* Prompt heuristic comes from OpenSSH */
3163 strncpy(s
->prompt
+ challengelen
,
3164 memchr(s
->prompt
, '\n', challengelen
) ?
3165 "": "\r\nResponse: ",
3166 (sizeof s
->prompt
) - challengelen
);
3167 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
3170 if (ssh
->cfg
.try_tis_auth
&&
3171 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3172 !s
->ccard_auth_refused
) {
3173 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3174 logevent("Requested CryptoCard authentication");
3175 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3177 if (pktin
->type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3178 logevent("CryptoCard authentication declined");
3179 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3180 s
->ccard_auth_refused
= 1;
3186 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3188 bombout(("CryptoCard challenge packet was badly formed"));
3191 logevent("Received CryptoCard challenge");
3192 if (challengelen
> sizeof(s
->prompt
) - 1)
3193 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3194 memcpy(s
->prompt
, challenge
, challengelen
);
3195 strncpy(s
->prompt
+ challengelen
,
3196 memchr(s
->prompt
, '\n', challengelen
) ?
3197 "" : "\r\nResponse: ",
3198 sizeof(s
->prompt
) - challengelen
);
3199 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
3202 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3203 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
3204 s
->username
, ssh
->savedhost
);
3206 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3207 char *comment
= NULL
;
3210 if (flags
& FLAG_VERBOSE
)
3211 c_write_str(ssh
, "Trying public key authentication.\r\n");
3212 logeventf(ssh
, "Trying public key \"%s\"",
3213 filename_to_str(&ssh
->cfg
.keyfile
));
3214 type
= key_type(&ssh
->cfg
.keyfile
);
3215 if (type
!= SSH_KEYTYPE_SSH1
) {
3216 sprintf(msgbuf
, "Key is of wrong type (%s)",
3217 key_type_to_str(type
));
3219 c_write_str(ssh
, msgbuf
);
3220 c_write_str(ssh
, "\r\n");
3221 s
->tried_publickey
= 1;
3224 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
3225 if (flags
& FLAG_VERBOSE
)
3226 c_write_str(ssh
, "No passphrase required.\r\n");
3229 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
3234 * Show password prompt, having first obtained it via a TIS
3235 * or CryptoCard exchange if we're doing TIS or CryptoCard
3239 if (!ssh_get_line(s
->prompt
, s
->password
,
3240 sizeof(s
->password
), TRUE
)) {
3242 * get_line failed to get a password (for example
3243 * because one was supplied on the command line
3244 * which has already failed to work). Terminate.
3246 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
3247 PKT_STR
, "No more passwords available to try",
3249 logevent("Unable to authenticate");
3250 connection_fatal(ssh
->frontend
, "Unable to authenticate");
3251 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3255 /* Prompt may have come from server. We've munged it a bit, so
3256 * we know it to be zero-terminated at least once. */
3257 int ret
; /* need not be saved over crReturn */
3258 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3261 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3263 crWaitUntil(!pktin
);
3264 ret
= process_userpass_input(ssh
, in
, inlen
);
3268 c_write_str(ssh
, "\r\n");
3272 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3274 * Try public key authentication with the specified
3277 s
->tried_publickey
= 1;
3280 const char *error
= NULL
;
3281 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3284 c_write_str(ssh
, "Couldn't load private key from ");
3285 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3286 c_write_str(ssh
, " (");
3287 c_write_str(ssh
, error
);
3288 c_write_str(ssh
, ").\r\n");
3289 continue; /* go and try password */
3292 c_write_str(ssh
, "Wrong passphrase.\r\n");
3293 s
->tried_publickey
= 0;
3294 continue; /* try again */
3299 * Send a public key attempt.
3301 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3302 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3305 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3306 c_write_str(ssh
, "Server refused our public key.\r\n");
3307 continue; /* go and try password */
3309 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3310 bombout(("Bizarre response to offer of public key"));
3316 unsigned char buffer
[32];
3317 Bignum challenge
, response
;
3319 if ((challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3320 bombout(("Server's RSA challenge was badly formatted"));
3323 response
= rsadecrypt(challenge
, &s
->key
);
3324 freebn(s
->key
.private_exponent
);/* burn the evidence */
3326 for (i
= 0; i
< 32; i
++) {
3327 buffer
[i
] = bignum_byte(response
, 31 - i
);
3331 MD5Update(&md5c
, buffer
, 32);
3332 MD5Update(&md5c
, s
->session_id
, 16);
3333 MD5Final(buffer
, &md5c
);
3335 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3336 PKT_DATA
, buffer
, 16, PKT_END
);
3343 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3344 if (flags
& FLAG_VERBOSE
)
3345 c_write_str(ssh
, "Failed to authenticate with"
3346 " our public key.\r\n");
3347 continue; /* go and try password */
3348 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3349 bombout(("Bizarre response to RSA authentication response"));
3353 break; /* we're through! */
3355 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3357 * Defence against traffic analysis: we send a
3358 * whole bunch of packets containing strings of
3359 * different lengths. One of these strings is the
3360 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3361 * The others are all random data in
3362 * SSH1_MSG_IGNORE packets. This way a passive
3363 * listener can't tell which is the password, and
3364 * hence can't deduce the password length.
3366 * Anybody with a password length greater than 16
3367 * bytes is going to have enough entropy in their
3368 * password that a listener won't find it _that_
3369 * much help to know how long it is. So what we'll
3372 * - if password length < 16, we send 15 packets
3373 * containing string lengths 1 through 15
3375 * - otherwise, we let N be the nearest multiple
3376 * of 8 below the password length, and send 8
3377 * packets containing string lengths N through
3378 * N+7. This won't obscure the order of
3379 * magnitude of the password length, but it will
3380 * introduce a bit of extra uncertainty.
3382 * A few servers (the old 1.2.18 through 1.2.22)
3383 * can't deal with SSH1_MSG_IGNORE. For these
3384 * servers, we need an alternative defence. We make
3385 * use of the fact that the password is interpreted
3386 * as a C string: so we can append a NUL, then some
3389 * One server (a Cisco one) can deal with neither
3390 * SSH1_MSG_IGNORE _nor_ a padded password string.
3391 * For this server we are left with no defences
3392 * against password length sniffing.
3394 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3396 * The server can deal with SSH1_MSG_IGNORE, so
3397 * we can use the primary defence.
3399 int bottom
, top
, pwlen
, i
;
3402 pwlen
= strlen(s
->password
);
3404 bottom
= 0; /* zero length passwords are OK! :-) */
3407 bottom
= pwlen
& ~7;
3411 assert(pwlen
>= bottom
&& pwlen
<= top
);
3413 randomstr
= snewn(top
+ 1, char);
3415 for (i
= bottom
; i
<= top
; i
++) {
3417 defer_packet(ssh
, s
->pwpkt_type
,
3418 PKTT_PASSWORD
, PKT_STR
, s
->password
,
3419 PKTT_OTHER
, PKT_END
);
3421 for (j
= 0; j
< i
; j
++) {
3423 randomstr
[j
] = random_byte();
3424 } while (randomstr
[j
] == '\0');
3426 randomstr
[i
] = '\0';
3427 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3428 PKT_STR
, randomstr
, PKT_END
);
3431 logevent("Sending password with camouflage packets");
3432 ssh_pkt_defersend(ssh
);
3435 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3437 * The server can't deal with SSH1_MSG_IGNORE
3438 * but can deal with padded passwords, so we
3439 * can use the secondary defence.
3445 len
= strlen(s
->password
);
3446 if (len
< sizeof(string
)) {
3448 strcpy(string
, s
->password
);
3449 len
++; /* cover the zero byte */
3450 while (len
< sizeof(string
)) {
3451 string
[len
++] = (char) random_byte();
3456 logevent("Sending length-padded password");
3457 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3458 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3459 PKTT_OTHER
, PKT_END
);
3462 * The server has _both_
3463 * BUG_CHOKES_ON_SSH1_IGNORE and
3464 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3465 * therefore nothing we can do.
3468 len
= strlen(s
->password
);
3469 logevent("Sending unpadded password");
3470 send_packet(ssh
, s
->pwpkt_type
,
3471 PKTT_PASSWORD
, PKT_INT
, len
,
3472 PKT_DATA
, s
->password
, len
,
3473 PKTT_OTHER
, PKT_END
);
3476 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3477 PKT_STR
, s
->password
, PKTT_OTHER
, PKT_END
);
3480 logevent("Sent password");
3481 memset(s
->password
, 0, strlen(s
->password
));
3483 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3484 if (flags
& FLAG_VERBOSE
)
3485 c_write_str(ssh
, "Access denied\r\n");
3486 logevent("Authentication refused");
3487 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3488 bombout(("Strange packet received, type %d", pktin
->type
));
3493 logevent("Authentication successful");
3498 void sshfwd_close(struct ssh_channel
*c
)
3502 if (ssh
->state
!= SSH_STATE_SESSION
) {
3503 assert(ssh
->state
== SSH_STATE_CLOSED
);
3507 if (c
&& !c
->closes
) {
3509 * If the channel's remoteid is -1, we have sent
3510 * CHANNEL_OPEN for this channel, but it hasn't even been
3511 * acknowledged by the server. So we must set a close flag
3512 * on it now, and then when the server acks the channel
3513 * open, we can close it then.
3515 if (((int)c
->remoteid
) != -1) {
3516 if (ssh
->version
== 1) {
3517 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3520 struct Packet
*pktout
;
3521 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3522 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
3523 ssh2_pkt_send(ssh
, pktout
);
3526 c
->closes
= 1; /* sent MSG_CLOSE */
3527 if (c
->type
== CHAN_X11
) {
3529 logevent("Forwarded X11 connection terminated");
3530 } else if (c
->type
== CHAN_SOCKDATA
||
3531 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3533 logevent("Forwarded port closed");
3538 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3542 if (ssh
->state
!= SSH_STATE_SESSION
) {
3543 assert(ssh
->state
== SSH_STATE_CLOSED
);
3547 if (ssh
->version
== 1) {
3548 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3549 PKT_INT
, c
->remoteid
,
3551 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3552 PKTT_OTHER
, PKT_END
);
3554 * In SSH1 we can return 0 here - implying that forwarded
3555 * connections are never individually throttled - because
3556 * the only circumstance that can cause throttling will be
3557 * the whole SSH connection backing up, in which case
3558 * _everything_ will be throttled as a whole.
3562 ssh2_add_channel_data(c
, buf
, len
);
3563 return ssh2_try_send(c
);
3567 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3571 if (ssh
->state
!= SSH_STATE_SESSION
) {
3572 assert(ssh
->state
== SSH_STATE_CLOSED
);
3576 if (ssh
->version
== 1) {
3577 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3578 c
->v
.v1
.throttling
= 0;
3579 ssh1_throttle(ssh
, -1);
3582 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3586 static void ssh_queueing_handler(Ssh ssh
, struct Packet
*pktin
)
3588 struct queued_handler
*qh
= ssh
->qhead
;
3592 assert(pktin
->type
== qh
->msg1
|| pktin
->type
== qh
->msg2
);
3595 assert(ssh
->packet_dispatch
[qh
->msg1
] == ssh_queueing_handler
);
3596 ssh
->packet_dispatch
[qh
->msg1
] = NULL
;
3599 assert(ssh
->packet_dispatch
[qh
->msg2
] == ssh_queueing_handler
);
3600 ssh
->packet_dispatch
[qh
->msg2
] = NULL
;
3604 ssh
->qhead
= qh
->next
;
3606 if (ssh
->qhead
->msg1
> 0) {
3607 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg1
] == NULL
);
3608 ssh
->packet_dispatch
[ssh
->qhead
->msg1
] = ssh_queueing_handler
;
3610 if (ssh
->qhead
->msg2
> 0) {
3611 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg2
] == NULL
);
3612 ssh
->packet_dispatch
[ssh
->qhead
->msg2
] = ssh_queueing_handler
;
3615 ssh
->qhead
= ssh
->qtail
= NULL
;
3616 ssh
->packet_dispatch
[pktin
->type
] = NULL
;
3619 qh
->handler(ssh
, pktin
, qh
->ctx
);
3624 static void ssh_queue_handler(Ssh ssh
, int msg1
, int msg2
,
3625 chandler_fn_t handler
, void *ctx
)
3627 struct queued_handler
*qh
;
3629 qh
= snew(struct queued_handler
);
3632 qh
->handler
= handler
;
3636 if (ssh
->qtail
== NULL
) {
3640 assert(ssh
->packet_dispatch
[qh
->msg1
] == NULL
);
3641 ssh
->packet_dispatch
[qh
->msg1
] = ssh_queueing_handler
;
3644 assert(ssh
->packet_dispatch
[qh
->msg2
] == NULL
);
3645 ssh
->packet_dispatch
[qh
->msg2
] = ssh_queueing_handler
;
3648 ssh
->qtail
->next
= qh
;
3653 static void ssh_rportfwd_succfail(Ssh ssh
, struct Packet
*pktin
, void *ctx
)
3655 struct ssh_rportfwd
*rpf
, *pf
= (struct ssh_rportfwd
*)ctx
;
3657 if (pktin
->type
== (ssh
->version
== 1 ? SSH1_SMSG_SUCCESS
:
3658 SSH2_MSG_REQUEST_SUCCESS
)) {
3659 logeventf(ssh
, "Remote port forwarding from %s enabled",
3662 logeventf(ssh
, "Remote port forwarding from %s refused",
3665 rpf
= del234(ssh
->rportfwds
, pf
);
3671 static void ssh_setup_portfwd(Ssh ssh
, const Config
*cfg
)
3673 char address_family
, type
;
3675 int sport
,dport
,sserv
,dserv
;
3676 char sports
[256], dports
[256], saddr
[256], host
[256];
3677 const char *portfwd_strptr
;
3679 portfwd_strptr
= cfg
->portfwd
;
3681 if (!ssh
->portfwds
) {
3682 ssh
->portfwds
= newtree234(ssh_portcmp
);
3685 * Go through the existing port forwardings and tag them
3686 * with keep==FALSE. Any that we want to keep will be
3687 * re-enabled as we go through the configuration and find
3688 * out which bits are the same as they were before.
3690 struct ssh_portfwd
*epf
;
3692 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3696 while (*portfwd_strptr
) {
3697 address_family
= 'A';
3699 while (*portfwd_strptr
&& *portfwd_strptr
!= '\t') {
3700 if (*portfwd_strptr
== 'A' ||
3701 *portfwd_strptr
== '4' ||
3702 *portfwd_strptr
== '6')
3703 address_family
= *portfwd_strptr
;
3704 else if (*portfwd_strptr
== 'L' ||
3705 *portfwd_strptr
== 'R' ||
3706 *portfwd_strptr
== 'D')
3707 type
= *portfwd_strptr
;
3714 while (*portfwd_strptr
&& *portfwd_strptr
!= '\t') {
3715 if (*portfwd_strptr
== ':') {
3717 * We've seen a colon in the middle of the
3718 * source port number. This means that
3719 * everything we've seen until now is the
3720 * source _address_, so we'll move it into
3721 * saddr and start sports from the beginning
3726 if (ssh
->version
== 1 && type
== 'R') {
3727 logeventf(ssh
, "SSH1 cannot handle remote source address "
3728 "spec \"%s\"; ignoring", sports
);
3730 strcpy(saddr
, sports
);
3733 if (n
< 255) sports
[n
++] = *portfwd_strptr
++;
3737 if (*portfwd_strptr
== '\t')
3740 while (*portfwd_strptr
&& *portfwd_strptr
!= ':') {
3741 if (n
< 255) host
[n
++] = *portfwd_strptr
++;
3744 if (*portfwd_strptr
== ':')
3747 while (*portfwd_strptr
) {
3748 if (n
< 255) dports
[n
++] = *portfwd_strptr
++;
3752 dport
= atoi(dports
);
3756 dport
= net_service_lookup(dports
);
3758 logeventf(ssh
, "Service lookup failed for destination"
3759 " port \"%s\"", dports
);
3763 while (*portfwd_strptr
) portfwd_strptr
++;
3765 portfwd_strptr
++; /* eat the NUL and move to next one */
3767 sport
= atoi(sports
);
3771 sport
= net_service_lookup(sports
);
3773 logeventf(ssh
, "Service lookup failed for source"
3774 " port \"%s\"", sports
);
3777 if (sport
&& dport
) {
3778 /* Set up a description of the source port. */
3779 struct ssh_portfwd
*pfrec
, *epfrec
;
3781 sportdesc
= dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
3782 (int)(*saddr?
strlen(saddr
):0), *saddr?saddr
:NULL
,
3783 (int)(*saddr?
1:0), ":",
3784 (int)(sserv ?
strlen(sports
) : 0), sports
,
3785 sserv
, "(", sport
, sserv
, ")");
3787 pfrec
= snew(struct ssh_portfwd
);
3789 pfrec
->saddr
= *saddr ?
dupstr(saddr
) : NULL
;
3790 pfrec
->sport
= sport
;
3791 pfrec
->daddr
= dupstr(host
);
3792 pfrec
->dport
= dport
;
3793 pfrec
->local
= NULL
;
3794 pfrec
->remote
= NULL
;
3795 pfrec
->addressfamily
= (address_family
== '4' ? ADDRTYPE_IPV4
:
3796 address_family
== '6' ? ADDRTYPE_IPV6
:
3799 epfrec
= add234(ssh
->portfwds
, pfrec
);
3800 if (epfrec
!= pfrec
) {
3802 * We already have a port forwarding with precisely
3803 * these parameters. Hence, no need to do anything;
3804 * simply tag the existing one as `keep'.
3806 epfrec
->keep
= TRUE
;
3807 free_portfwd(pfrec
);
3808 } else if (type
== 'L') {
3809 /* Verbose description of the destination port */
3810 char *dportdesc
= dupprintf("%s:%.*s%.*s%d%.*s",
3812 (int)(dserv ?
strlen(dports
) : 0), dports
,
3813 dserv
, "(", dport
, dserv
, ")");
3814 const char *err
= pfd_addforward(host
, dport
,
3815 *saddr ? saddr
: NULL
,
3816 sport
, ssh
, &ssh
->cfg
,
3818 pfrec
->addressfamily
);
3820 logeventf(ssh
, "Local %sport %s forward to %s%s%s",
3821 pfrec
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
3822 pfrec
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
3823 sportdesc
, dportdesc
,
3824 err ?
" failed: " : "", err
);
3827 } else if (type
== 'D') {
3828 const char *err
= pfd_addforward(NULL
, -1,
3829 *saddr ? saddr
: NULL
,
3830 sport
, ssh
, &ssh
->cfg
,
3832 pfrec
->addressfamily
);
3834 logeventf(ssh
, "Local %sport %s SOCKS dynamic forward%s%s",
3835 pfrec
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
3836 pfrec
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
3838 err ?
" setup failed: " : "", err
);
3840 struct ssh_rportfwd
*pf
;
3843 * Ensure the remote port forwardings tree exists.
3845 if (!ssh
->rportfwds
) {
3846 if (ssh
->version
== 1)
3847 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3849 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
3852 pf
= snew(struct ssh_rportfwd
);
3853 strcpy(pf
->dhost
, host
);
3856 if (add234(ssh
->rportfwds
, pf
) != pf
) {
3857 logeventf(ssh
, "Duplicate remote port forwarding to %s:%d",
3861 logeventf(ssh
, "Requesting remote port %s"
3862 " forward to %s:%.*s%.*s%d%.*s",
3864 (int)(dserv ?
strlen(dports
) : 0), dports
,
3865 dserv
, "(", dport
, dserv
, ")");
3867 pf
->sportdesc
= sportdesc
;
3872 if (ssh
->version
== 1) {
3873 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
3878 ssh_queue_handler(ssh
, SSH1_SMSG_SUCCESS
,
3880 ssh_rportfwd_succfail
, pf
);
3882 struct Packet
*pktout
;
3883 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
3884 ssh2_pkt_addstring(pktout
, "tcpip-forward");
3885 ssh2_pkt_addbool(pktout
, 1);/* want reply */
3887 ssh2_pkt_addstring(pktout
, saddr
);
3888 } else if (ssh
->cfg
.rport_acceptall
) {
3889 ssh2_pkt_addstring(pktout
, "0.0.0.0");
3891 ssh2_pkt_addstring(pktout
, "127.0.0.1");
3893 ssh2_pkt_adduint32(pktout
, sport
);
3894 ssh2_pkt_send(ssh
, pktout
);
3896 ssh_queue_handler(ssh
, SSH2_MSG_REQUEST_SUCCESS
,
3897 SSH2_MSG_REQUEST_FAILURE
,
3898 ssh_rportfwd_succfail
, pf
);
3907 * Now go through and destroy any port forwardings which were
3911 struct ssh_portfwd
*epf
;
3913 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3917 message
= dupprintf("%s port forwarding from %s%s%d",
3918 epf
->type
== 'L' ?
"local" :
3919 epf
->type
== 'R' ?
"remote" : "dynamic",
3920 epf
->saddr ? epf
->saddr
: "",
3921 epf
->saddr ?
":" : "",
3924 if (epf
->type
!= 'D') {
3925 char *msg2
= dupprintf("%s to %s:%d", message
,
3926 epf
->daddr
, epf
->dport
);
3931 logeventf(ssh
, "Cancelling %s", message
);
3935 struct ssh_rportfwd
*rpf
= epf
->remote
;
3936 struct Packet
*pktout
;
3939 * Cancel the port forwarding at the server
3942 if (ssh
->version
== 1) {
3944 * We cannot cancel listening ports on the
3945 * server side in SSH1! There's no message
3946 * to support it. Instead, we simply remove
3947 * the rportfwd record from the local end
3948 * so that any connections the server tries
3949 * to make on it are rejected.
3952 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
3953 ssh2_pkt_addstring(pktout
, "cancel-tcpip-forward");
3954 ssh2_pkt_addbool(pktout
, 0);/* _don't_ want reply */
3956 ssh2_pkt_addstring(pktout
, epf
->saddr
);
3957 } else if (ssh
->cfg
.rport_acceptall
) {
3958 ssh2_pkt_addstring(pktout
, "0.0.0.0");
3960 ssh2_pkt_addstring(pktout
, "127.0.0.1");
3962 ssh2_pkt_adduint32(pktout
, epf
->sport
);
3963 ssh2_pkt_send(ssh
, pktout
);
3966 del234(ssh
->rportfwds
, rpf
);
3968 } else if (epf
->local
) {
3969 pfd_terminate(epf
->local
);
3972 delpos234(ssh
->portfwds
, i
);
3974 i
--; /* so we don't skip one in the list */
3979 static void ssh1_smsg_stdout_stderr_data(Ssh ssh
, struct Packet
*pktin
)
3982 int stringlen
, bufsize
;
3984 ssh_pkt_getstring(pktin
, &string
, &stringlen
);
3985 if (string
== NULL
) {
3986 bombout(("Incoming terminal data packet was badly formed"));
3990 bufsize
= from_backend(ssh
->frontend
, pktin
->type
== SSH1_SMSG_STDERR_DATA
,
3992 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3993 ssh
->v1_stdout_throttling
= 1;
3994 ssh1_throttle(ssh
, +1);
3998 static void ssh1_smsg_x11_open(Ssh ssh
, struct Packet
*pktin
)
4000 /* Remote side is trying to open a channel to talk to our
4001 * X-Server. Give them back a local channel number. */
4002 struct ssh_channel
*c
;
4003 int remoteid
= ssh_pkt_getuint32(pktin
);
4005 logevent("Received X11 connect request");
4006 /* Refuse if X11 forwarding is disabled. */
4007 if (!ssh
->X11_fwd_enabled
) {
4008 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4009 PKT_INT
, remoteid
, PKT_END
);
4010 logevent("Rejected X11 connect request");
4012 c
= snew(struct ssh_channel
);
4015 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
4016 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
4017 logevent("Opening X11 forward connection failed");
4019 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4020 PKT_INT
, remoteid
, PKT_END
);
4023 ("Opening X11 forward connection succeeded");
4024 c
->remoteid
= remoteid
;
4025 c
->localid
= alloc_channel_id(ssh
);
4027 c
->v
.v1
.throttling
= 0;
4028 c
->type
= CHAN_X11
; /* identify channel type */
4029 add234(ssh
->channels
, c
);
4030 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4031 PKT_INT
, c
->remoteid
, PKT_INT
,
4032 c
->localid
, PKT_END
);
4033 logevent("Opened X11 forward channel");
4038 static void ssh1_smsg_agent_open(Ssh ssh
, struct Packet
*pktin
)
4040 /* Remote side is trying to open a channel to talk to our
4041 * agent. Give them back a local channel number. */
4042 struct ssh_channel
*c
;
4043 int remoteid
= ssh_pkt_getuint32(pktin
);
4045 /* Refuse if agent forwarding is disabled. */
4046 if (!ssh
->agentfwd_enabled
) {
4047 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4048 PKT_INT
, remoteid
, PKT_END
);
4050 c
= snew(struct ssh_channel
);
4052 c
->remoteid
= remoteid
;
4053 c
->localid
= alloc_channel_id(ssh
);
4055 c
->v
.v1
.throttling
= 0;
4056 c
->type
= CHAN_AGENT
; /* identify channel type */
4057 c
->u
.a
.lensofar
= 0;
4058 add234(ssh
->channels
, c
);
4059 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4060 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
4065 static void ssh1_msg_port_open(Ssh ssh
, struct Packet
*pktin
)
4067 /* Remote side is trying to open a channel to talk to a
4068 * forwarded port. Give them back a local channel number. */
4069 struct ssh_channel
*c
;
4070 struct ssh_rportfwd pf
, *pfp
;
4073 char *host
, buf
[1024];
4075 c
= snew(struct ssh_channel
);
4078 remoteid
= ssh_pkt_getuint32(pktin
);
4079 ssh_pkt_getstring(pktin
, &host
, &hostsize
);
4080 port
= ssh_pkt_getuint32(pktin
);
4082 if (hostsize
>= lenof(pf
.dhost
))
4083 hostsize
= lenof(pf
.dhost
)-1;
4084 memcpy(pf
.dhost
, host
, hostsize
);
4085 pf
.dhost
[hostsize
] = '\0';
4087 pfp
= find234(ssh
->rportfwds
, &pf
, NULL
);
4090 sprintf(buf
, "Rejected remote port open request for %s:%d",
4093 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4094 PKT_INT
, remoteid
, PKT_END
);
4096 sprintf(buf
, "Received remote port open request for %s:%d",
4099 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
4100 c
, &ssh
->cfg
, pfp
->pfrec
->addressfamily
);
4103 sprintf(buf
, "Port open failed: %s", e
);
4106 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4107 PKT_INT
, remoteid
, PKT_END
);
4109 c
->remoteid
= remoteid
;
4110 c
->localid
= alloc_channel_id(ssh
);
4112 c
->v
.v1
.throttling
= 0;
4113 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
4114 add234(ssh
->channels
, c
);
4115 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4116 PKT_INT
, c
->remoteid
, PKT_INT
,
4117 c
->localid
, PKT_END
);
4118 logevent("Forwarded port opened successfully");
4123 static void ssh1_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
4125 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4126 unsigned int localid
= ssh_pkt_getuint32(pktin
);
4127 struct ssh_channel
*c
;
4129 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4130 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4131 c
->remoteid
= localid
;
4132 c
->type
= CHAN_SOCKDATA
;
4133 c
->v
.v1
.throttling
= 0;
4134 pfd_confirm(c
->u
.pfd
.s
);
4137 if (c
&& c
->closes
) {
4139 * We have a pending close on this channel,
4140 * which we decided on before the server acked
4141 * the channel open. So now we know the
4142 * remoteid, we can close it again.
4144 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
4145 PKT_INT
, c
->remoteid
, PKT_END
);
4149 static void ssh1_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
4151 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4152 struct ssh_channel
*c
;
4154 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4155 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4156 logevent("Forwarded connection refused by server");
4157 pfd_close(c
->u
.pfd
.s
);
4158 del234(ssh
->channels
, c
);
4163 static void ssh1_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
4165 /* Remote side closes a channel. */
4166 unsigned i
= ssh_pkt_getuint32(pktin
);
4167 struct ssh_channel
*c
;
4168 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4169 if (c
&& ((int)c
->remoteid
) != -1) {
4172 (pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
4174 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
4175 logevent("Forwarded X11 connection terminated");
4176 assert(c
->u
.x11
.s
!= NULL
);
4177 x11_close(c
->u
.x11
.s
);
4180 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
4181 logevent("Forwarded port closed");
4182 assert(c
->u
.pfd
.s
!= NULL
);
4183 pfd_close(c
->u
.pfd
.s
);
4187 c
->closes
|= (closetype
<< 2); /* seen this message */
4188 if (!(c
->closes
& closetype
)) {
4189 send_packet(ssh
, pktin
->type
, PKT_INT
, c
->remoteid
,
4191 c
->closes
|= closetype
; /* sent it too */
4194 if (c
->closes
== 15) {
4195 del234(ssh
->channels
, c
);
4199 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4200 pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
4201 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
4206 static void ssh1_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
4208 /* Data sent down one of our channels. */
4209 int i
= ssh_pkt_getuint32(pktin
);
4212 struct ssh_channel
*c
;
4214 ssh_pkt_getstring(pktin
, &p
, &len
);
4216 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4221 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
4224 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
4227 /* Data for an agent message. Buffer it. */
4229 if (c
->u
.a
.lensofar
< 4) {
4230 unsigned int l
= min(4 - c
->u
.a
.lensofar
, len
);
4231 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
4235 c
->u
.a
.lensofar
+= l
;
4237 if (c
->u
.a
.lensofar
== 4) {
4239 4 + GET_32BIT(c
->u
.a
.msglen
);
4240 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
4242 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
4244 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
4246 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
4248 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
4252 c
->u
.a
.lensofar
+= l
;
4254 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
4257 if (agent_query(c
->u
.a
.message
,
4260 ssh_agentf_callback
, c
))
4261 ssh_agentf_callback(c
, reply
, replylen
);
4262 sfree(c
->u
.a
.message
);
4263 c
->u
.a
.lensofar
= 0;
4266 bufsize
= 0; /* agent channels never back up */
4269 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4270 c
->v
.v1
.throttling
= 1;
4271 ssh1_throttle(ssh
, +1);
4276 static void ssh1_smsg_exit_status(Ssh ssh
, struct Packet
*pktin
)
4279 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
4280 sprintf(buf
, "Server sent command exit status %d",
4283 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
4285 * In case `helpful' firewalls or proxies tack
4286 * extra human-readable text on the end of the
4287 * session which we might mistake for another
4288 * encrypted packet, we close the session once
4289 * we've sent EXIT_CONFIRMATION.
4291 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4294 static void do_ssh1_connection(Ssh ssh
, unsigned char *in
, int inlen
,
4295 struct Packet
*pktin
)
4297 crBegin(ssh
->do_ssh1_connection_crstate
);
4299 ssh
->packet_dispatch
[SSH1_SMSG_STDOUT_DATA
] =
4300 ssh
->packet_dispatch
[SSH1_SMSG_STDERR_DATA
] =
4301 ssh1_smsg_stdout_stderr_data
;
4303 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
] =
4304 ssh1_msg_channel_open_confirmation
;
4305 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_FAILURE
] =
4306 ssh1_msg_channel_open_failure
;
4307 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE
] =
4308 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
] =
4309 ssh1_msg_channel_close
;
4310 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_DATA
] = ssh1_msg_channel_data
;
4311 ssh
->packet_dispatch
[SSH1_SMSG_EXIT_STATUS
] = ssh1_smsg_exit_status
;
4313 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
4314 logevent("Requesting agent forwarding");
4315 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
4319 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4320 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4321 bombout(("Protocol confusion"));
4323 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4324 logevent("Agent forwarding refused");
4326 logevent("Agent forwarding enabled");
4327 ssh
->agentfwd_enabled
= TRUE
;
4328 ssh
->packet_dispatch
[SSH1_SMSG_AGENT_OPEN
] = ssh1_smsg_agent_open
;
4332 if (ssh
->cfg
.x11_forward
) {
4333 char proto
[20], data
[64];
4334 logevent("Requesting X11 forwarding");
4335 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
4336 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
4337 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
4338 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
4339 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4340 PKT_STR
, proto
, PKT_STR
, data
,
4341 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
4344 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4345 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
4350 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4351 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4352 bombout(("Protocol confusion"));
4354 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4355 logevent("X11 forwarding refused");
4357 logevent("X11 forwarding enabled");
4358 ssh
->X11_fwd_enabled
= TRUE
;
4359 ssh
->packet_dispatch
[SSH1_SMSG_X11_OPEN
] = ssh1_smsg_x11_open
;
4363 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
4364 ssh
->packet_dispatch
[SSH1_MSG_PORT_OPEN
] = ssh1_msg_port_open
;
4366 if (!ssh
->cfg
.nopty
) {
4367 /* Unpick the terminal-speed string. */
4368 /* XXX perhaps we should allow no speeds to be sent. */
4369 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
4370 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
4371 /* Send the pty request. */
4372 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
4373 PKT_STR
, ssh
->cfg
.termtype
,
4374 PKT_INT
, ssh
->term_height
,
4375 PKT_INT
, ssh
->term_width
,
4376 PKT_INT
, 0, PKT_INT
, 0, /* width,height in pixels */
4377 PKT_CHAR
, 192, PKT_INT
, ssh
->ispeed
, /* TTY_OP_ISPEED */
4378 PKT_CHAR
, 193, PKT_INT
, ssh
->ospeed
, /* TTY_OP_OSPEED */
4379 PKT_CHAR
, 0, PKT_END
);
4380 ssh
->state
= SSH_STATE_INTERMED
;
4384 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4385 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4386 bombout(("Protocol confusion"));
4388 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4389 c_write_str(ssh
, "Server refused to allocate pty\r\n");
4390 ssh
->editing
= ssh
->echoing
= 1;
4392 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
4393 ssh
->ospeed
, ssh
->ispeed
);
4395 ssh
->editing
= ssh
->echoing
= 1;
4398 if (ssh
->cfg
.compression
) {
4399 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
4403 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4404 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4405 bombout(("Protocol confusion"));
4407 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4408 c_write_str(ssh
, "Server refused to compress\r\n");
4410 logevent("Started compression");
4411 ssh
->v1_compressing
= TRUE
;
4412 ssh
->cs_comp_ctx
= zlib_compress_init();
4413 logevent("Initialised zlib (RFC1950) compression");
4414 ssh
->sc_comp_ctx
= zlib_decompress_init();
4415 logevent("Initialised zlib (RFC1950) decompression");
4419 * Start the shell or command.
4421 * Special case: if the first-choice command is an SSH2
4422 * subsystem (hence not usable here) and the second choice
4423 * exists, we fall straight back to that.
4426 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
4428 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
4429 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
4430 ssh
->fallback_cmd
= TRUE
;
4433 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
4435 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
4436 logevent("Started session");
4439 ssh
->state
= SSH_STATE_SESSION
;
4440 if (ssh
->size_needed
)
4441 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
4442 if (ssh
->eof_needed
)
4443 ssh_special(ssh
, TS_EOF
);
4446 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
4448 ssh
->channels
= newtree234(ssh_channelcmp
);
4452 * By this point, most incoming packets are already being
4453 * handled by the dispatch table, and we need only pay
4454 * attention to the unusual ones.
4459 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
4460 /* may be from EXEC_SHELL on some servers */
4461 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4462 /* may be from EXEC_SHELL on some servers
4463 * if no pty is available or in other odd cases. Ignore */
4465 bombout(("Strange packet received: type %d", pktin
->type
));
4470 int len
= min(inlen
, 512);
4471 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4472 PKT_INT
, len
, PKT_DATA
, in
, len
,
4473 PKTT_OTHER
, PKT_END
);
4484 * Handle the top-level SSH2 protocol.
4486 static void ssh1_msg_debug(Ssh ssh
, struct Packet
*pktin
)
4491 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4492 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
4497 static void ssh1_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
4499 /* log reason code in disconnect message */
4503 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4504 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen
, msg
));
4507 void ssh_msg_ignore(Ssh ssh
, struct Packet
*pktin
)
4509 /* Do nothing, because we're ignoring it! Duhh. */
4512 static void ssh1_protocol_setup(Ssh ssh
)
4517 * Most messages are handled by the coroutines.
4519 for (i
= 0; i
< 256; i
++)
4520 ssh
->packet_dispatch
[i
] = NULL
;
4523 * These special message types we install handlers for.
4525 ssh
->packet_dispatch
[SSH1_MSG_DISCONNECT
] = ssh1_msg_disconnect
;
4526 ssh
->packet_dispatch
[SSH1_MSG_IGNORE
] = ssh_msg_ignore
;
4527 ssh
->packet_dispatch
[SSH1_MSG_DEBUG
] = ssh1_msg_debug
;
4530 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
4531 struct Packet
*pktin
)
4533 if (ssh
->state
== SSH_STATE_CLOSED
)
4536 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
4537 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
4541 if (!ssh
->protocol_initial_phase_done
) {
4542 if (do_ssh1_login(ssh
, in
, inlen
, pktin
))
4543 ssh
->protocol_initial_phase_done
= TRUE
;
4548 do_ssh1_connection(ssh
, in
, inlen
, pktin
);
4552 * Utility routine for decoding comma-separated strings in KEXINIT.
4554 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
4557 if (!needle
|| !haystack
) /* protect against null pointers */
4559 needlen
= strlen(needle
);
4562 * Is it at the start of the string?
4564 if (haylen
>= needlen
&& /* haystack is long enough */
4565 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4566 (haylen
== needlen
|| haystack
[needlen
] == ',')
4567 /* either , or EOS follows */
4571 * If not, search for the next comma and resume after that.
4572 * If no comma found, terminate.
4574 while (haylen
> 0 && *haystack
!= ',')
4575 haylen
--, haystack
++;
4578 haylen
--, haystack
++; /* skip over comma itself */
4583 * SSH2 key creation method.
4585 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
4586 unsigned char *sessid
, char chr
,
4587 unsigned char *keyspace
)
4590 /* First 20 bytes. */
4592 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4594 SHA_Bytes(&s
, H
, 20);
4595 SHA_Bytes(&s
, &chr
, 1);
4596 SHA_Bytes(&s
, sessid
, 20);
4597 SHA_Final(&s
, keyspace
);
4598 /* Next 20 bytes. */
4600 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4602 SHA_Bytes(&s
, H
, 20);
4603 SHA_Bytes(&s
, keyspace
, 20);
4604 SHA_Final(&s
, keyspace
+ 20);
4608 * Handle the SSH2 transport layer.
4610 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
,
4611 struct Packet
*pktin
)
4613 struct do_ssh2_transport_state
{
4614 int nbits
, pbits
, warn
;
4615 Bignum p
, g
, e
, f
, K
;
4616 int kex_init_value
, kex_reply_value
;
4617 const struct ssh_mac
**maclist
;
4619 const struct ssh2_cipher
*cscipher_tobe
;
4620 const struct ssh2_cipher
*sccipher_tobe
;
4621 const struct ssh_mac
*csmac_tobe
;
4622 const struct ssh_mac
*scmac_tobe
;
4623 const struct ssh_compress
*cscomp_tobe
;
4624 const struct ssh_compress
*sccomp_tobe
;
4625 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4626 int hostkeylen
, siglen
;
4627 void *hkey
; /* actual host key */
4628 unsigned char exchange_hash
[20];
4629 int n_preferred_kex
;
4630 const struct ssh_kex
*preferred_kex
[KEX_MAX
];
4631 int n_preferred_ciphers
;
4632 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
4633 const struct ssh_compress
*preferred_comp
;
4635 struct Packet
*pktout
;
4637 crState(do_ssh2_transport_state
);
4639 crBegin(ssh
->do_ssh2_transport_crstate
);
4641 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
4642 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
4643 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
4650 * Set up the preferred key exchange. (NULL => warn below here)
4652 s
->n_preferred_kex
= 0;
4653 for (i
= 0; i
< KEX_MAX
; i
++) {
4654 switch (ssh
->cfg
.ssh_kexlist
[i
]) {
4656 s
->preferred_kex
[s
->n_preferred_kex
++] =
4657 &ssh_diffiehellman_gex
;
4660 s
->preferred_kex
[s
->n_preferred_kex
++] =
4661 &ssh_diffiehellman_group14
;
4664 s
->preferred_kex
[s
->n_preferred_kex
++] =
4665 &ssh_diffiehellman_group1
;
4668 /* Flag for later. Don't bother if it's the last in
4670 if (i
< KEX_MAX
- 1) {
4671 s
->preferred_kex
[s
->n_preferred_kex
++] = NULL
;
4681 * Set up the preferred ciphers. (NULL => warn below here)
4683 s
->n_preferred_ciphers
= 0;
4684 for (i
= 0; i
< CIPHER_MAX
; i
++) {
4685 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
4686 case CIPHER_BLOWFISH
:
4687 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
4690 if (ssh
->cfg
.ssh2_des_cbc
) {
4691 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
4695 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
4698 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
4701 /* Flag for later. Don't bother if it's the last in
4703 if (i
< CIPHER_MAX
- 1) {
4704 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
4712 * Set up preferred compression.
4714 if (ssh
->cfg
.compression
)
4715 s
->preferred_comp
= &ssh_zlib
;
4717 s
->preferred_comp
= &ssh_comp_none
;
4720 * Be prepared to work around the buggy MAC problem.
4722 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
4723 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
4725 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
4729 int i
, j
, commalist_started
;
4732 * Enable queueing of outgoing auth- or connection-layer
4733 * packets while we are in the middle of a key exchange.
4735 ssh
->queueing
= TRUE
;
4738 * Flag that KEX is in progress.
4740 ssh
->kex_in_progress
= TRUE
;
4743 * Construct and send our key exchange packet.
4745 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEXINIT
);
4746 for (i
= 0; i
< 16; i
++)
4747 ssh2_pkt_addbyte(s
->pktout
, (unsigned char) random_byte());
4748 /* List key exchange algorithms. */
4749 ssh2_pkt_addstring_start(s
->pktout
);
4750 commalist_started
= 0;
4751 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4752 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4753 if (!k
) continue; /* warning flag */
4754 if (commalist_started
)
4755 ssh2_pkt_addstring_str(s
->pktout
, ",");
4756 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_kex
[i
]->name
);
4757 commalist_started
= 1;
4759 /* List server host key algorithms. */
4760 ssh2_pkt_addstring_start(s
->pktout
);
4761 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4762 ssh2_pkt_addstring_str(s
->pktout
, hostkey_algs
[i
]->name
);
4763 if (i
< lenof(hostkey_algs
) - 1)
4764 ssh2_pkt_addstring_str(s
->pktout
, ",");
4766 /* List client->server encryption algorithms. */
4767 ssh2_pkt_addstring_start(s
->pktout
);
4768 commalist_started
= 0;
4769 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4770 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4771 if (!c
) continue; /* warning flag */
4772 for (j
= 0; j
< c
->nciphers
; j
++) {
4773 if (commalist_started
)
4774 ssh2_pkt_addstring_str(s
->pktout
, ",");
4775 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4776 commalist_started
= 1;
4779 /* List server->client encryption algorithms. */
4780 ssh2_pkt_addstring_start(s
->pktout
);
4781 commalist_started
= 0;
4782 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4783 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4784 if (!c
) continue; /* warning flag */
4785 for (j
= 0; j
< c
->nciphers
; j
++) {
4786 if (commalist_started
)
4787 ssh2_pkt_addstring_str(s
->pktout
, ",");
4788 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4789 commalist_started
= 1;
4792 /* List client->server MAC algorithms. */
4793 ssh2_pkt_addstring_start(s
->pktout
);
4794 for (i
= 0; i
< s
->nmacs
; i
++) {
4795 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4796 if (i
< s
->nmacs
- 1)
4797 ssh2_pkt_addstring_str(s
->pktout
, ",");
4799 /* List server->client MAC algorithms. */
4800 ssh2_pkt_addstring_start(s
->pktout
);
4801 for (i
= 0; i
< s
->nmacs
; i
++) {
4802 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4803 if (i
< s
->nmacs
- 1)
4804 ssh2_pkt_addstring_str(s
->pktout
, ",");
4806 /* List client->server compression algorithms. */
4807 ssh2_pkt_addstring_start(s
->pktout
);
4808 assert(lenof(compressions
) > 1);
4809 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4810 for (i
= 0; i
< lenof(compressions
); i
++) {
4811 const struct ssh_compress
*c
= compressions
[i
];
4812 if (c
!= s
->preferred_comp
) {
4813 ssh2_pkt_addstring_str(s
->pktout
, ",");
4814 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4817 /* List server->client compression algorithms. */
4818 ssh2_pkt_addstring_start(s
->pktout
);
4819 assert(lenof(compressions
) > 1);
4820 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4821 for (i
= 0; i
< lenof(compressions
); i
++) {
4822 const struct ssh_compress
*c
= compressions
[i
];
4823 if (c
!= s
->preferred_comp
) {
4824 ssh2_pkt_addstring_str(s
->pktout
, ",");
4825 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4828 /* List client->server languages. Empty list. */
4829 ssh2_pkt_addstring_start(s
->pktout
);
4830 /* List server->client languages. Empty list. */
4831 ssh2_pkt_addstring_start(s
->pktout
);
4832 /* First KEX packet does _not_ follow, because we're not that brave. */
4833 ssh2_pkt_addbool(s
->pktout
, FALSE
);
4835 ssh2_pkt_adduint32(s
->pktout
, 0);
4838 ssh
->exhash
= ssh
->exhashbase
;
4839 sha_string(&ssh
->exhash
, s
->pktout
->data
+ 5, s
->pktout
->length
- 5);
4841 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
4845 if (pktin
->length
> 5)
4846 sha_string(&ssh
->exhash
, pktin
->data
+ 5, pktin
->length
- 5);
4849 * Now examine the other side's KEXINIT to see what we're up
4856 if (pktin
->type
!= SSH2_MSG_KEXINIT
) {
4857 bombout(("expected key exchange packet from server"));
4861 ssh
->hostkey
= NULL
;
4862 s
->cscipher_tobe
= NULL
;
4863 s
->sccipher_tobe
= NULL
;
4864 s
->csmac_tobe
= NULL
;
4865 s
->scmac_tobe
= NULL
;
4866 s
->cscomp_tobe
= NULL
;
4867 s
->sccomp_tobe
= NULL
;
4868 pktin
->savedpos
+= 16; /* skip garbage cookie */
4869 ssh_pkt_getstring(pktin
, &str
, &len
); /* key exchange algorithms */
4871 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4872 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4875 } else if (in_commasep_string(k
->name
, str
, len
)) {
4880 askalg(ssh
->frontend
, "key-exchange algorithm",
4886 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
4887 str ? str
: "(null)"));
4890 ssh_pkt_getstring(pktin
, &str
, &len
); /* host key algorithms */
4891 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4892 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
4893 ssh
->hostkey
= hostkey_algs
[i
];
4897 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server cipher */
4899 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4900 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4904 for (j
= 0; j
< c
->nciphers
; j
++) {
4905 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4906 s
->cscipher_tobe
= c
->list
[j
];
4911 if (s
->cscipher_tobe
) {
4913 askalg(ssh
->frontend
, "client-to-server cipher",
4914 s
->cscipher_tobe
->name
);
4918 if (!s
->cscipher_tobe
) {
4919 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
4920 str ? str
: "(null)"));
4924 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client cipher */
4926 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4927 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4931 for (j
= 0; j
< c
->nciphers
; j
++) {
4932 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4933 s
->sccipher_tobe
= c
->list
[j
];
4938 if (s
->sccipher_tobe
) {
4940 askalg(ssh
->frontend
, "server-to-client cipher",
4941 s
->sccipher_tobe
->name
);
4945 if (!s
->sccipher_tobe
) {
4946 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
4947 str ? str
: "(null)"));
4951 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server mac */
4952 for (i
= 0; i
< s
->nmacs
; i
++) {
4953 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4954 s
->csmac_tobe
= s
->maclist
[i
];
4958 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client mac */
4959 for (i
= 0; i
< s
->nmacs
; i
++) {
4960 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4961 s
->scmac_tobe
= s
->maclist
[i
];
4965 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server compression */
4966 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4967 const struct ssh_compress
*c
=
4968 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4969 if (in_commasep_string(c
->name
, str
, len
)) {
4974 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client compression */
4975 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4976 const struct ssh_compress
*c
=
4977 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4978 if (in_commasep_string(c
->name
, str
, len
)) {
4986 * Work out the number of bits of key we will need from the key
4987 * exchange. We start with the maximum key length of either
4993 csbits
= s
->cscipher_tobe
->keylen
;
4994 scbits
= s
->sccipher_tobe
->keylen
;
4995 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
4997 /* The keys only have 160-bit entropy, since they're based on
4998 * a SHA-1 hash. So cap the key size at 160 bits. */
5003 * If we're doing Diffie-Hellman group exchange, start by
5004 * requesting a group.
5006 if (!ssh
->kex
->pdata
) {
5007 logevent("Doing Diffie-Hellman group exchange");
5008 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
5010 * Work out how big a DH group we will need to allow that
5013 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
5014 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
5015 ssh2_pkt_adduint32(s
->pktout
, s
->pbits
);
5016 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5019 if (pktin
->type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
5020 bombout(("expected key exchange group packet from server"));
5023 s
->p
= ssh2_pkt_getmp(pktin
);
5024 s
->g
= ssh2_pkt_getmp(pktin
);
5025 if (!s
->p
|| !s
->g
) {
5026 bombout(("unable to read mp-ints from incoming group packet"));
5029 ssh
->kex_ctx
= dh_setup_gex(s
->p
, s
->g
);
5030 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
5031 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
5033 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP
;
5034 ssh
->kex_ctx
= dh_setup_group(ssh
->kex
);
5035 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
5036 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
5037 logeventf(ssh
, "Using Diffie-Hellman with standard group \"%s\"",
5038 ssh
->kex
->groupname
);
5041 logevent("Doing Diffie-Hellman key exchange");
5043 * Now generate and send e for Diffie-Hellman.
5045 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
5046 s
->pktout
= ssh2_pkt_init(s
->kex_init_value
);
5047 ssh2_pkt_addmp(s
->pktout
, s
->e
);
5048 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5051 if (pktin
->type
!= s
->kex_reply_value
) {
5052 bombout(("expected key exchange reply packet from server"));
5055 ssh_pkt_getstring(pktin
, &s
->hostkeydata
, &s
->hostkeylen
);
5056 s
->f
= ssh2_pkt_getmp(pktin
);
5058 bombout(("unable to parse key exchange reply packet"));
5061 ssh_pkt_getstring(pktin
, &s
->sigdata
, &s
->siglen
);
5063 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
5065 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
5066 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5067 sha_uint32(&ssh
->exhash
, s
->pbits
);
5068 sha_mpint(&ssh
->exhash
, s
->p
);
5069 sha_mpint(&ssh
->exhash
, s
->g
);
5071 sha_mpint(&ssh
->exhash
, s
->e
);
5072 sha_mpint(&ssh
->exhash
, s
->f
);
5073 sha_mpint(&ssh
->exhash
, s
->K
);
5074 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
5076 dh_cleanup(ssh
->kex_ctx
);
5077 ssh
->kex_ctx
= NULL
;
5080 debug(("Exchange hash is:\n"));
5081 dmemdump(s
->exchange_hash
, 20);
5084 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
5086 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
5087 (char *)s
->exchange_hash
, 20)) {
5088 bombout(("Server's host key did not match the signature supplied"));
5093 * Authenticate remote host: verify host key. (We've already
5094 * checked the signature of the exchange hash.)
5096 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
5097 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
5098 verify_ssh_host_key(ssh
->frontend
,
5099 ssh
->savedhost
, ssh
->savedport
, ssh
->hostkey
->keytype
,
5100 s
->keystr
, s
->fingerprint
);
5101 if (s
->first_kex
) { /* don't bother logging this in rekeys */
5102 logevent("Host key fingerprint is:");
5103 logevent(s
->fingerprint
);
5105 sfree(s
->fingerprint
);
5107 ssh
->hostkey
->freekey(s
->hkey
);
5110 * The exchange hash from the very first key exchange is also
5111 * the session id, used in session key construction and
5115 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
5116 sizeof(s
->exchange_hash
));
5119 * Send SSH2_MSG_NEWKEYS.
5121 s
->pktout
= ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
5122 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5123 ssh
->outgoing_data_size
= 0; /* start counting from here */
5126 * We've sent client NEWKEYS, so create and initialise
5127 * client-to-server session keys.
5129 if (ssh
->cs_cipher_ctx
)
5130 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
5131 ssh
->cscipher
= s
->cscipher_tobe
;
5132 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
5134 if (ssh
->cs_mac_ctx
)
5135 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
5136 ssh
->csmac
= s
->csmac_tobe
;
5137 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
5139 if (ssh
->cs_comp_ctx
)
5140 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
5141 ssh
->cscomp
= s
->cscomp_tobe
;
5142 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
5145 * Set IVs on client-to-server keys. Here we use the exchange
5146 * hash from the _first_ key exchange.
5149 unsigned char keyspace
[40];
5150 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
5151 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
5152 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
5153 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
5154 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
5155 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
5158 logeventf(ssh
, "Initialised %.200s client->server encryption",
5159 ssh
->cscipher
->text_name
);
5160 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
5161 ssh
->csmac
->text_name
);
5162 if (ssh
->cscomp
->text_name
)
5163 logeventf(ssh
, "Initialised %s compression",
5164 ssh
->cscomp
->text_name
);
5167 * Now our end of the key exchange is complete, we can send all
5168 * our queued higher-layer packets.
5170 ssh
->queueing
= FALSE
;
5171 ssh2_pkt_queuesend(ssh
);
5174 * Expect SSH2_MSG_NEWKEYS from server.
5177 if (pktin
->type
!= SSH2_MSG_NEWKEYS
) {
5178 bombout(("expected new-keys packet from server"));
5181 ssh
->incoming_data_size
= 0; /* start counting from here */
5184 * We've seen server NEWKEYS, so create and initialise
5185 * server-to-client session keys.
5187 if (ssh
->sc_cipher_ctx
)
5188 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
5189 ssh
->sccipher
= s
->sccipher_tobe
;
5190 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
5192 if (ssh
->sc_mac_ctx
)
5193 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
5194 ssh
->scmac
= s
->scmac_tobe
;
5195 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
5197 if (ssh
->sc_comp_ctx
)
5198 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
5199 ssh
->sccomp
= s
->sccomp_tobe
;
5200 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
5203 * Set IVs on server-to-client keys. Here we use the exchange
5204 * hash from the _first_ key exchange.
5207 unsigned char keyspace
[40];
5208 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
5209 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
5210 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
5211 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
5212 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
5213 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
5215 logeventf(ssh
, "Initialised %.200s server->client encryption",
5216 ssh
->sccipher
->text_name
);
5217 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
5218 ssh
->scmac
->text_name
);
5219 if (ssh
->sccomp
->text_name
)
5220 logeventf(ssh
, "Initialised %s decompression",
5221 ssh
->sccomp
->text_name
);
5224 * Free key exchange data.
5228 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5234 * Key exchange is over. Schedule a timer for our next rekey.
5236 ssh
->kex_in_progress
= FALSE
;
5237 ssh
->last_rekey
= GETTICKCOUNT();
5238 if (ssh
->cfg
.ssh_rekey_time
!= 0)
5239 ssh
->next_rekey
= schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5243 * If this is the first key exchange phase, we must pass the
5244 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5245 * wants to see it but because it will need time to initialise
5246 * itself before it sees an actual packet. In subsequent key
5247 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5248 * it would only confuse the layer above.
5250 if (!s
->first_kex
) {
5256 * Now we're encrypting. Begin returning 1 to the protocol main
5257 * function so that other things can run on top of the
5258 * transport. If we ever see a KEXINIT, we must go back to the
5261 * We _also_ go back to the start if we see pktin==NULL and
5262 * inlen==-1, because this is a special signal meaning
5263 * `initiate client-driven rekey', and `in' contains a message
5264 * giving the reason for the rekey.
5266 while (!((pktin
&& pktin
->type
== SSH2_MSG_KEXINIT
) ||
5267 (!pktin
&& inlen
== -1))) {
5271 logevent("Server initiated key re-exchange");
5273 logevent((char *)in
);
5275 goto begin_key_exchange
;
5281 * Add data to an SSH2 channel output buffer.
5283 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
5286 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
5290 * Attempt to send data on an SSH2 channel.
5292 static int ssh2_try_send(struct ssh_channel
*c
)
5295 struct Packet
*pktout
;
5297 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
5300 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
5301 if ((unsigned)len
> c
->v
.v2
.remwindow
)
5302 len
= c
->v
.v2
.remwindow
;
5303 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
5304 len
= c
->v
.v2
.remmaxpkt
;
5305 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
5306 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5307 dont_log_data(ssh
, pktout
, PKTLOG_OMIT
);
5308 ssh2_pkt_addstring_start(pktout
);
5309 ssh2_pkt_addstring_data(pktout
, data
, len
);
5310 end_log_omission(ssh
, pktout
);
5311 ssh2_pkt_send(ssh
, pktout
);
5312 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
5313 c
->v
.v2
.remwindow
-= len
;
5317 * After having sent as much data as we can, return the amount
5320 return bufchain_size(&c
->v
.v2
.outbuffer
);
5324 * Potentially enlarge the window on an SSH2 channel.
5326 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
5331 * Never send WINDOW_ADJUST for a channel that the remote side
5332 * already thinks it's closed; there's no point, since it won't
5333 * be sending any more data anyway.
5338 if (newwin
> c
->v
.v2
.locwindow
) {
5339 struct Packet
*pktout
;
5341 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5342 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5343 ssh2_pkt_adduint32(pktout
, newwin
- c
->v
.v2
.locwindow
);
5344 ssh2_pkt_send(ssh
, pktout
);
5345 c
->v
.v2
.locwindow
= newwin
;
5349 static void ssh2_msg_channel_window_adjust(Ssh ssh
, struct Packet
*pktin
)
5351 unsigned i
= ssh_pkt_getuint32(pktin
);
5352 struct ssh_channel
*c
;
5353 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5354 if (c
&& !c
->closes
)
5355 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
5358 static void ssh2_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
5361 unsigned int length
;
5362 unsigned i
= ssh_pkt_getuint32(pktin
);
5363 struct ssh_channel
*c
;
5364 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5366 return; /* nonexistent channel */
5367 if (pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5368 ssh_pkt_getuint32(pktin
) != SSH2_EXTENDED_DATA_STDERR
)
5369 return; /* extended but not stderr */
5370 ssh_pkt_getstring(pktin
, &data
, &length
);
5373 c
->v
.v2
.locwindow
-= length
;
5375 case CHAN_MAINSESSION
:
5377 from_backend(ssh
->frontend
, pktin
->type
==
5378 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5382 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5385 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5388 while (length
> 0) {
5389 if (c
->u
.a
.lensofar
< 4) {
5390 unsigned int l
= min(4 - c
->u
.a
.lensofar
, length
);
5391 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5395 c
->u
.a
.lensofar
+= l
;
5397 if (c
->u
.a
.lensofar
== 4) {
5399 4 + GET_32BIT(c
->u
.a
.msglen
);
5400 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
5402 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5404 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5406 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5408 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5412 c
->u
.a
.lensofar
+= l
;
5414 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5417 if (agent_query(c
->u
.a
.message
,
5420 ssh_agentf_callback
, c
))
5421 ssh_agentf_callback(c
, reply
, replylen
);
5422 sfree(c
->u
.a
.message
);
5423 c
->u
.a
.lensofar
= 0;
5430 * If we are not buffering too much data,
5431 * enlarge the window again at the remote side.
5433 if (bufsize
< OUR_V2_WINSIZE
)
5434 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5438 static void ssh2_msg_channel_eof(Ssh ssh
, struct Packet
*pktin
)
5440 unsigned i
= ssh_pkt_getuint32(pktin
);
5441 struct ssh_channel
*c
;
5443 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5445 return; /* nonexistent channel */
5447 if (c
->type
== CHAN_X11
) {
5449 * Remote EOF on an X11 channel means we should
5450 * wrap up and close the channel ourselves.
5452 x11_close(c
->u
.x11
.s
);
5454 } else if (c
->type
== CHAN_AGENT
) {
5456 } else if (c
->type
== CHAN_SOCKDATA
) {
5457 pfd_close(c
->u
.pfd
.s
);
5462 static void ssh2_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
5464 unsigned i
= ssh_pkt_getuint32(pktin
);
5465 struct ssh_channel
*c
;
5466 struct Packet
*pktout
;
5468 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5469 if (!c
|| ((int)c
->remoteid
) == -1) {
5470 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5471 c ?
"half-open" : "nonexistent", i
));
5474 /* Do pre-close processing on the channel. */
5476 case CHAN_MAINSESSION
:
5477 ssh
->mainchan
= NULL
;
5478 update_specials_menu(ssh
->frontend
);
5481 if (c
->u
.x11
.s
!= NULL
)
5482 x11_close(c
->u
.x11
.s
);
5489 if (c
->u
.pfd
.s
!= NULL
)
5490 pfd_close(c
->u
.pfd
.s
);
5494 if (c
->closes
== 0) {
5495 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5496 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5497 ssh2_pkt_send(ssh
, pktout
);
5499 del234(ssh
->channels
, c
);
5500 bufchain_clear(&c
->v
.v2
.outbuffer
);
5504 * See if that was the last channel left open.
5505 * (This is only our termination condition if we're
5506 * not running in -N mode.)
5508 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
5509 logevent("All channels closed. Disconnecting");
5512 * We used to send SSH_MSG_DISCONNECT here,
5513 * because I'd believed that _every_ conforming
5514 * SSH2 connection had to end with a disconnect
5515 * being sent by at least one side; apparently
5516 * I was wrong and it's perfectly OK to
5517 * unceremoniously slam the connection shut
5518 * when you're done, and indeed OpenSSH feels
5519 * this is more polite than sending a
5520 * DISCONNECT. So now we don't.
5522 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5523 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5524 ssh2_pkt_addstring(s
->pktout
, "All open channels closed");
5525 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
5526 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5528 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5532 static void ssh2_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
5534 unsigned i
= ssh_pkt_getuint32(pktin
);
5535 struct ssh_channel
*c
;
5536 struct Packet
*pktout
;
5538 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5540 return; /* nonexistent channel */
5541 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5542 return; /* dunno why they're confirming this */
5543 c
->remoteid
= ssh_pkt_getuint32(pktin
);
5544 c
->type
= CHAN_SOCKDATA
;
5545 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
5546 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
5548 pfd_confirm(c
->u
.pfd
.s
);
5551 * We have a pending close on this channel,
5552 * which we decided on before the server acked
5553 * the channel open. So now we know the
5554 * remoteid, we can close it again.
5556 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5557 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5558 ssh2_pkt_send(ssh
, pktout
);
5562 static void ssh2_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
5564 static const char *const reasons
[] = {
5565 "<unknown reason code>",
5566 "Administratively prohibited",
5568 "Unknown channel type",
5569 "Resource shortage",
5571 unsigned i
= ssh_pkt_getuint32(pktin
);
5572 unsigned reason_code
;
5573 char *reason_string
;
5576 struct ssh_channel
*c
;
5577 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5579 return; /* nonexistent channel */
5580 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5581 return; /* dunno why they're failing this */
5583 reason_code
= ssh_pkt_getuint32(pktin
);
5584 if (reason_code
>= lenof(reasons
))
5585 reason_code
= 0; /* ensure reasons[reason_code] in range */
5586 ssh_pkt_getstring(pktin
, &reason_string
, &reason_length
);
5587 message
= dupprintf("Forwarded connection refused by"
5588 " server: %s [%.*s]", reasons
[reason_code
],
5589 reason_length
, reason_string
);
5593 pfd_close(c
->u
.pfd
.s
);
5595 del234(ssh
->channels
, c
);
5599 static void ssh2_msg_channel_request(Ssh ssh
, struct Packet
*pktin
)
5603 int typelen
, want_reply
;
5604 int reply
= SSH2_MSG_CHANNEL_FAILURE
; /* default */
5605 struct ssh_channel
*c
;
5606 struct Packet
*pktout
;
5608 localid
= ssh_pkt_getuint32(pktin
);
5609 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5610 want_reply
= ssh2_pkt_getbool(pktin
);
5613 * First, check that the channel exists. Otherwise,
5614 * we can instantly disconnect with a rude message.
5616 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
5619 sprintf(buf
, "Received channel request for nonexistent"
5620 " channel %d", localid
);
5622 pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5623 ssh2_pkt_adduint32(pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5624 ssh2_pkt_addstring(pktout
, buf
);
5625 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5626 ssh2_pkt_send_noqueue(ssh
, pktout
);
5627 connection_fatal(ssh
->frontend
, "%s", buf
);
5628 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5633 * Having got the channel number, we now look at
5634 * the request type string to see if it's something
5637 if (c
== ssh
->mainchan
) {
5639 * We recognise "exit-status" and "exit-signal" on
5640 * the primary channel.
5642 if (typelen
== 11 &&
5643 !memcmp(type
, "exit-status", 11)) {
5645 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
5646 logeventf(ssh
, "Server sent command exit status %d",
5648 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5650 } else if (typelen
== 11 &&
5651 !memcmp(type
, "exit-signal", 11)) {
5653 int is_plausible
= TRUE
, is_int
= FALSE
;
5654 char *fmt_sig
= "", *fmt_msg
= "";
5656 int msglen
= 0, core
= FALSE
;
5657 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
5658 * provide an `int' for the signal, despite its
5659 * having been a `string' in the drafts since at
5660 * least 2001. (Fixed in session.c 1.147.) Try to
5661 * infer which we can safely parse it as. */
5663 unsigned char *p
= pktin
->body
+
5665 long len
= pktin
->length
- pktin
->savedpos
;
5666 unsigned long num
= GET_32BIT(p
); /* what is it? */
5667 /* If it's 0, it hardly matters; assume string */
5671 int maybe_int
= FALSE
, maybe_str
= FALSE
;
5672 #define CHECK_HYPOTHESIS(offset, result) \
5675 if (q >= 0 && q+4 <= len) { \
5676 q = q + 4 + GET_32BIT(p+q); \
5677 if (q >= 0 && q+4 <= len && \
5678 (q = q + 4 + GET_32BIT(p+q)) && q == len) \
5682 CHECK_HYPOTHESIS(4+1, maybe_int
);
5683 CHECK_HYPOTHESIS(4+num
+1, maybe_str
);
5684 #undef CHECK_HYPOTHESIS
5685 if (maybe_int
&& !maybe_str
)
5687 else if (!maybe_int
&& maybe_str
)
5690 /* Crikey. Either or neither. Panic. */
5691 is_plausible
= FALSE
;
5696 /* Old non-standard OpenSSH. */
5697 int signum
= ssh_pkt_getuint32(pktin
);
5698 fmt_sig
= dupprintf(" %d", signum
);
5700 /* As per the drafts. */
5703 ssh_pkt_getstring(pktin
, &sig
, &siglen
);
5704 /* Signal name isn't supposed to be blank, but
5705 * let's cope gracefully if it is. */
5707 fmt_sig
= dupprintf(" \"%.*s\"",
5711 core
= ssh2_pkt_getbool(pktin
);
5712 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
5714 fmt_msg
= dupprintf(" (\"%.*s\")", msglen
, msg
);
5716 /* ignore lang tag */
5717 } /* else don't attempt to parse */
5718 logeventf(ssh
, "Server exited on signal%s%s%s",
5719 fmt_sig
, core ?
" (core dumped)" : "",
5721 if (*fmt_sig
) sfree(fmt_sig
);
5722 if (*fmt_msg
) sfree(fmt_msg
);
5723 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5728 * This is a channel request we don't know
5729 * about, so we now either ignore the request
5730 * or respond with CHANNEL_FAILURE, depending
5733 reply
= SSH2_MSG_CHANNEL_FAILURE
;
5736 pktout
= ssh2_pkt_init(reply
);
5737 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5738 ssh2_pkt_send(ssh
, pktout
);
5742 static void ssh2_msg_global_request(Ssh ssh
, struct Packet
*pktin
)
5745 int typelen
, want_reply
;
5746 struct Packet
*pktout
;
5748 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5749 want_reply
= ssh2_pkt_getbool(pktin
);
5752 * We currently don't support any global requests
5753 * at all, so we either ignore the request or
5754 * respond with REQUEST_FAILURE, depending on
5758 pktout
= ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
5759 ssh2_pkt_send(ssh
, pktout
);
5763 static void ssh2_msg_channel_open(Ssh ssh
, struct Packet
*pktin
)
5771 struct ssh_channel
*c
;
5772 unsigned remid
, winsize
, pktsize
;
5773 struct Packet
*pktout
;
5775 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5776 c
= snew(struct ssh_channel
);
5779 remid
= ssh_pkt_getuint32(pktin
);
5780 winsize
= ssh_pkt_getuint32(pktin
);
5781 pktsize
= ssh_pkt_getuint32(pktin
);
5783 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5786 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5787 addrstr
= snewn(peeraddrlen
+1, char);
5788 memcpy(addrstr
, peeraddr
, peeraddrlen
);
5789 addrstr
[peeraddrlen
] = '\0';
5790 peerport
= ssh_pkt_getuint32(pktin
);
5792 logeventf(ssh
, "Received X11 connect request from %s:%d",
5795 if (!ssh
->X11_fwd_enabled
)
5796 error
= "X11 forwarding is not enabled";
5797 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
5798 ssh
->x11auth
, addrstr
, peerport
,
5799 &ssh
->cfg
) != NULL
) {
5800 error
= "Unable to open an X11 connection";
5802 logevent("Opening X11 forward connection succeeded");
5807 } else if (typelen
== 15 &&
5808 !memcmp(type
, "forwarded-tcpip", 15)) {
5809 struct ssh_rportfwd pf
, *realpf
;
5812 ssh_pkt_getstring(pktin
, &dummy
, &dummylen
);/* skip address */
5813 pf
.sport
= ssh_pkt_getuint32(pktin
);
5814 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5815 peerport
= ssh_pkt_getuint32(pktin
);
5816 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
5817 logeventf(ssh
, "Received remote port %d open request "
5818 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
5819 if (realpf
== NULL
) {
5820 error
= "Remote port is not recognised";
5822 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
5826 realpf
->pfrec
->addressfamily
);
5827 logeventf(ssh
, "Attempting to forward remote port to "
5828 "%s:%d", realpf
->dhost
, realpf
->dport
);
5830 logeventf(ssh
, "Port open failed: %s", e
);
5831 error
= "Port open failed";
5833 logevent("Forwarded port opened successfully");
5834 c
->type
= CHAN_SOCKDATA
;
5837 } else if (typelen
== 22 &&
5838 !memcmp(type
, "auth-agent@openssh.com", 3)) {
5839 if (!ssh
->agentfwd_enabled
)
5840 error
= "Agent forwarding is not enabled";
5842 c
->type
= CHAN_AGENT
; /* identify channel type */
5843 c
->u
.a
.lensofar
= 0;
5846 error
= "Unsupported channel type requested";
5849 c
->remoteid
= remid
;
5851 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
5852 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5853 ssh2_pkt_adduint32(pktout
, SSH2_OPEN_CONNECT_FAILED
);
5854 ssh2_pkt_addstring(pktout
, error
);
5855 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5856 ssh2_pkt_send(ssh
, pktout
);
5857 logeventf(ssh
, "Rejected channel open: %s", error
);
5860 c
->localid
= alloc_channel_id(ssh
);
5862 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5863 c
->v
.v2
.remwindow
= winsize
;
5864 c
->v
.v2
.remmaxpkt
= pktsize
;
5865 bufchain_init(&c
->v
.v2
.outbuffer
);
5866 add234(ssh
->channels
, c
);
5867 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
5868 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5869 ssh2_pkt_adduint32(pktout
, c
->localid
);
5870 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);
5871 ssh2_pkt_adduint32(pktout
, 0x4000UL
); /* our max pkt size */
5872 ssh2_pkt_send(ssh
, pktout
);
5877 * Handle the SSH2 userauth and connection layers.
5879 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
5880 struct Packet
*pktin
)
5882 struct do_ssh2_authconn_state
{
5884 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
5886 AUTH_KEYBOARD_INTERACTIVE
5890 AUTH_TYPE_PUBLICKEY
,
5891 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
5892 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
5894 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
5895 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
5897 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
5898 int tried_pubkey_config
, tried_agent
, tried_keyb_inter
;
5899 int kbd_inter_running
;
5901 int num_prompts
, curr_prompt
, echo
;
5906 void *publickey_blob
;
5907 int publickey_bloblen
;
5908 unsigned char request
[5], *response
, *p
;
5912 char *pkblob
, *alg
, *commentp
;
5913 int pklen
, alglen
, commentlen
;
5914 int siglen
, retlen
, len
;
5915 char *q
, *agentreq
, *ret
;
5917 int num_env
, env_left
, env_ok
;
5918 struct Packet
*pktout
;
5920 crState(do_ssh2_authconn_state
);
5922 crBegin(ssh
->do_ssh2_authconn_crstate
);
5925 * Request userauth protocol, and await a response to it.
5927 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
5928 ssh2_pkt_addstring(s
->pktout
, "ssh-userauth");
5929 ssh2_pkt_send(ssh
, s
->pktout
);
5930 crWaitUntilV(pktin
);
5931 if (pktin
->type
!= SSH2_MSG_SERVICE_ACCEPT
) {
5932 bombout(("Server refused user authentication protocol"));
5937 * We repeat this whole loop, including the username prompt,
5938 * until we manage a successful authentication. If the user
5939 * types the wrong _password_, they can be sent back to the
5940 * beginning to try another username, if this is configured on.
5941 * (If they specify a username in the config, they are never
5942 * asked, even if they do give a wrong password.)
5944 * I think this best serves the needs of
5946 * - the people who have no configuration, no keys, and just
5947 * want to try repeated (username,password) pairs until they
5948 * type both correctly
5950 * - people who have keys and configuration but occasionally
5951 * need to fall back to passwords
5953 * - people with a key held in Pageant, who might not have
5954 * logged in to a particular machine before; so they want to
5955 * type a username, and then _either_ their key will be
5956 * accepted, _or_ they will type a password. If they mistype
5957 * the username they will want to be able to get back and
5960 s
->username
[0] = '\0';
5961 s
->got_username
= FALSE
;
5966 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
5968 * We got a username last time round this loop, and
5969 * with change_username turned off we don't try to get
5972 } else if (!*ssh
->cfg
.username
) {
5973 if (ssh_get_line
&& !ssh_getline_pw_only
) {
5974 if (!ssh_get_line("login as: ",
5975 s
->username
, sizeof(s
->username
), FALSE
)) {
5977 * get_line failed to get a username.
5980 logevent("No username provided. Abandoning session.");
5981 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5985 int ret
; /* need not be saved across crReturn */
5986 c_write_str(ssh
, "login as: ");
5988 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
5990 crWaitUntilV(!pktin
);
5991 ret
= process_userpass_input(ssh
, in
, inlen
);
5995 c_write_str(ssh
, "\r\n");
5997 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
6000 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
6001 s
->username
[sizeof(s
->username
)-1] = '\0';
6002 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
6003 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
6004 c_write_str(ssh
, stuff
);
6008 s
->got_username
= TRUE
;
6011 * Send an authentication request using method "none": (a)
6012 * just in case it succeeds, and (b) so that we know what
6013 * authentication methods we can usefully try next.
6015 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6017 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6018 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6019 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");/* service requested */
6020 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6021 ssh2_pkt_send(ssh
, s
->pktout
);
6022 s
->type
= AUTH_TYPE_NONE
;
6024 s
->we_are_in
= FALSE
;
6026 s
->tried_pubkey_config
= FALSE
;
6027 s
->tried_agent
= FALSE
;
6028 s
->tried_keyb_inter
= FALSE
;
6029 s
->kbd_inter_running
= FALSE
;
6030 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
6031 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
6033 logeventf(ssh
, "Reading private key file \"%.150s\"",
6034 filename_to_str(&ssh
->cfg
.keyfile
));
6035 keytype
= key_type(&ssh
->cfg
.keyfile
);
6036 if (keytype
== SSH_KEYTYPE_SSH2
) {
6038 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
6039 &s
->publickey_bloblen
, NULL
);
6042 logeventf(ssh
, "Unable to use this key file (%s)",
6043 key_type_to_str(keytype
));
6044 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
6046 filename_to_str(&ssh
->cfg
.keyfile
),
6047 key_type_to_str(keytype
));
6048 c_write_str(ssh
, msgbuf
);
6050 s
->publickey_blob
= NULL
;
6053 s
->publickey_blob
= NULL
;
6057 * Wait for the result of the last authentication request.
6060 crWaitUntilV(pktin
);
6061 while (pktin
->type
== SSH2_MSG_USERAUTH_BANNER
) {
6065 * Don't show the banner if we're operating in
6066 * non-verbose non-interactive mode. (It's probably
6067 * a script, which means nobody will read the
6068 * banner _anyway_, and moreover the printing of
6069 * the banner will screw up processing on the
6070 * output of (say) plink.)
6072 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
6073 ssh_pkt_getstring(pktin
, &banner
, &size
);
6075 c_write_untrusted(ssh
, banner
, size
);
6077 crWaitUntilV(pktin
);
6079 if (pktin
->type
== SSH2_MSG_USERAUTH_SUCCESS
) {
6080 logevent("Access granted");
6081 s
->we_are_in
= TRUE
;
6085 if (s
->kbd_inter_running
&&
6086 pktin
->type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6088 * This is either a further set-of-prompts packet
6089 * in keyboard-interactive authentication, or it's
6090 * the same one and we came back here with `gotit'
6091 * set. In the former case, we must reset the
6092 * curr_prompt variable.
6096 } else if (pktin
->type
!= SSH2_MSG_USERAUTH_FAILURE
) {
6097 bombout(("Strange packet received during authentication: type %d",
6105 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6106 * we can look at the string in it and know what we can
6107 * helpfully try next.
6109 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
) {
6112 ssh_pkt_getstring(pktin
, &methods
, &methlen
);
6113 s
->kbd_inter_running
= FALSE
;
6114 if (!ssh2_pkt_getbool(pktin
)) {
6116 * We have received an unequivocal Access
6117 * Denied. This can translate to a variety of
6120 * - if we'd just tried "none" authentication,
6121 * it's not worth printing anything at all
6123 * - if we'd just tried a public key _offer_,
6124 * the message should be "Server refused our
6125 * key" (or no message at all if the key
6126 * came from Pageant)
6128 * - if we'd just tried anything else, the
6129 * message really should be "Access denied".
6131 * Additionally, if we'd just tried password
6132 * authentication, we should break out of this
6133 * whole loop so as to go back to the username
6134 * prompt (iff we're configured to allow
6135 * username change attempts).
6137 if (s
->type
== AUTH_TYPE_NONE
) {
6139 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
6140 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
6141 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
6142 c_write_str(ssh
, "Server refused our key\r\n");
6143 logevent("Server refused public key");
6144 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
6145 /* server declined keyboard-interactive; ignore */
6147 c_write_str(ssh
, "Access denied\r\n");
6148 logevent("Access denied");
6149 if (s
->type
== AUTH_TYPE_PASSWORD
&&
6150 ssh
->cfg
.change_username
) {
6151 /* XXX perhaps we should allow
6152 * keyboard-interactive to do this too? */
6153 s
->we_are_in
= FALSE
;
6158 c_write_str(ssh
, "Further authentication required\r\n");
6159 logevent("Further authentication required");
6163 in_commasep_string("publickey", methods
, methlen
);
6165 in_commasep_string("password", methods
, methlen
);
6166 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
6167 in_commasep_string("keyboard-interactive", methods
, methlen
);
6171 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6175 * Most password/passphrase prompts will be
6176 * non-echoing, so we set this to 0 by default.
6177 * Exception is that some keyboard-interactive prompts
6178 * can be echoing, in which case we'll set this to 1.
6182 if (!s
->method
&& s
->can_pubkey
&&
6183 agent_exists() && !s
->tried_agent
) {
6185 * Attempt public-key authentication using Pageant.
6190 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6191 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6193 s
->tried_agent
= TRUE
;
6195 logevent("Pageant is running. Requesting keys.");
6197 /* Request the keys held by the agent. */
6198 PUT_32BIT(s
->request
, 1);
6199 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
6200 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
6201 ssh_agent_callback
, ssh
)) {
6205 bombout(("Unexpected data from server while"
6206 " waiting for agent response"));
6209 } while (pktin
|| inlen
> 0);
6210 r
= ssh
->agent_response
;
6211 s
->responselen
= ssh
->agent_response_len
;
6213 s
->response
= (unsigned char *) r
;
6214 if (s
->response
&& s
->responselen
>= 5 &&
6215 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
6216 s
->p
= s
->response
+ 5;
6217 s
->nkeys
= GET_32BIT(s
->p
);
6221 sprintf(buf
, "Pageant has %d SSH2 keys", s
->nkeys
);
6224 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
6229 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
6232 s
->pklen
= GET_32BIT(s
->p
);
6234 if (s
->publickey_blob
&&
6235 s
->pklen
== s
->publickey_bloblen
&&
6236 !memcmp(s
->p
, s
->publickey_blob
,
6237 s
->publickey_bloblen
)) {
6238 logevent("This key matches configured key file");
6239 s
->tried_pubkey_config
= 1;
6241 s
->pkblob
= (char *)s
->p
;
6243 s
->alglen
= GET_32BIT(s
->pkblob
);
6244 s
->alg
= s
->pkblob
+ 4;
6245 s
->commentlen
= GET_32BIT(s
->p
);
6247 s
->commentp
= (char *)s
->p
;
6248 s
->p
+= s
->commentlen
;
6249 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6250 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6251 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6252 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6253 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6254 ssh2_pkt_addstring_start(s
->pktout
);
6255 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6256 ssh2_pkt_addstring_start(s
->pktout
);
6257 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6258 ssh2_pkt_send(ssh
, s
->pktout
);
6260 crWaitUntilV(pktin
);
6261 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6262 logevent("Key refused");
6266 if (flags
& FLAG_VERBOSE
) {
6267 c_write_str(ssh
, "Authenticating with "
6269 c_write(ssh
, s
->commentp
, s
->commentlen
);
6270 c_write_str(ssh
, "\" from agent\r\n");
6274 * Server is willing to accept the key.
6275 * Construct a SIGN_REQUEST.
6277 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6278 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6279 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6280 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6281 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6282 ssh2_pkt_addstring_start(s
->pktout
);
6283 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6284 ssh2_pkt_addstring_start(s
->pktout
);
6285 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6287 s
->siglen
= s
->pktout
->length
- 5 + 4 + 20;
6288 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6290 s
->len
= 1; /* message type */
6291 s
->len
+= 4 + s
->pklen
; /* key blob */
6292 s
->len
+= 4 + s
->siglen
; /* data to sign */
6293 s
->len
+= 4; /* flags */
6294 s
->agentreq
= snewn(4 + s
->len
, char);
6295 PUT_32BIT(s
->agentreq
, s
->len
);
6296 s
->q
= s
->agentreq
+ 4;
6297 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
6298 PUT_32BIT(s
->q
, s
->pklen
);
6300 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
6302 PUT_32BIT(s
->q
, s
->siglen
);
6304 /* Now the data to be signed... */
6305 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6306 PUT_32BIT(s
->q
, 20);
6309 memcpy(s
->q
, ssh
->v2_session_id
, 20);
6311 memcpy(s
->q
, s
->pktout
->data
+ 5,
6312 s
->pktout
->length
- 5);
6313 s
->q
+= s
->pktout
->length
- 5;
6314 /* And finally the (zero) flags word. */
6316 if (!agent_query(s
->agentreq
, s
->len
+ 4,
6318 ssh_agent_callback
, ssh
)) {
6322 bombout(("Unexpected data from server"
6323 " while waiting for agent"
6327 } while (pktin
|| inlen
> 0);
6328 vret
= ssh
->agent_response
;
6329 s
->retlen
= ssh
->agent_response_len
;
6334 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
6335 logevent("Sending Pageant's response");
6336 ssh2_add_sigblob(ssh
, s
->pktout
,
6337 s
->pkblob
, s
->pklen
,
6339 GET_32BIT(s
->ret
+ 5));
6340 ssh2_pkt_send(ssh
, s
->pktout
);
6345 ("Pageant failed to answer challenge");
6356 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
6357 && !s
->tried_pubkey_config
) {
6358 unsigned char *pub_blob
;
6359 char *algorithm
, *comment
;
6362 s
->tried_pubkey_config
= TRUE
;
6364 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6365 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6368 * Try the public key supplied in the configuration.
6370 * First, offer the public blob to see if the server is
6371 * willing to accept it.
6374 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
6379 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6380 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6381 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6382 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6383 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6384 ssh2_pkt_addstring(s
->pktout
, algorithm
);
6385 ssh2_pkt_addstring_start(s
->pktout
);
6386 ssh2_pkt_addstring_data(s
->pktout
, (char *)pub_blob
,
6388 ssh2_pkt_send(ssh
, s
->pktout
);
6389 logevent("Offered public key");
6391 crWaitUntilV(pktin
);
6392 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6394 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
6395 continue; /* key refused; give up on it */
6398 logevent("Offer of public key accepted");
6400 * Actually attempt a serious authentication using
6403 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
6404 sprintf(s
->pwprompt
,
6405 "Passphrase for key \"%.100s\": ",
6411 if (flags
& FLAG_VERBOSE
) {
6412 c_write_str(ssh
, "Authenticating with public key \"");
6413 c_write_str(ssh
, comment
);
6414 c_write_str(ssh
, "\"\r\n");
6416 s
->method
= AUTH_PUBLICKEY_FILE
;
6420 if (!s
->method
&& s
->can_keyb_inter
&& !s
->tried_keyb_inter
) {
6421 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6422 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6423 s
->tried_keyb_inter
= TRUE
;
6425 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6426 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6428 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6429 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6430 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6431 ssh2_pkt_addstring(s
->pktout
, "keyboard-interactive"); /* method */
6432 ssh2_pkt_addstring(s
->pktout
, ""); /* lang */
6433 ssh2_pkt_addstring(s
->pktout
, "");
6434 ssh2_pkt_send(ssh
, s
->pktout
);
6436 crWaitUntilV(pktin
);
6437 if (pktin
->type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6438 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
)
6440 logevent("Keyboard-interactive authentication refused");
6441 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
6445 s
->kbd_inter_running
= TRUE
;
6449 if (s
->kbd_inter_running
) {
6450 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6451 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6452 s
->tried_keyb_inter
= TRUE
;
6454 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6455 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6457 if (s
->curr_prompt
== 0) {
6459 * We've got a fresh USERAUTH_INFO_REQUEST.
6460 * Display header data, and start going through
6463 char *name
, *inst
, *lang
;
6464 int name_len
, inst_len
, lang_len
;
6466 ssh_pkt_getstring(pktin
, &name
, &name_len
);
6467 ssh_pkt_getstring(pktin
, &inst
, &inst_len
);
6468 ssh_pkt_getstring(pktin
, &lang
, &lang_len
);
6470 c_write_untrusted(ssh
, name
, name_len
);
6471 c_write_str(ssh
, "\r\n");
6474 c_write_untrusted(ssh
, inst
, inst_len
);
6475 c_write_str(ssh
, "\r\n");
6477 s
->num_prompts
= ssh_pkt_getuint32(pktin
);
6481 * If there are prompts remaining in the packet,
6482 * display one and get a response.
6484 if (s
->curr_prompt
< s
->num_prompts
) {
6488 ssh_pkt_getstring(pktin
, &prompt
, &prompt_len
);
6489 if (prompt_len
> 0) {
6490 static const char trunc
[] = "<prompt truncated>: ";
6491 static const int prlen
= sizeof(s
->pwprompt
) -
6493 if (prompt_len
> prlen
) {
6494 memcpy(s
->pwprompt
, prompt
, prlen
);
6495 strcpy(s
->pwprompt
+ prlen
, trunc
);
6497 memcpy(s
->pwprompt
, prompt
, prompt_len
);
6498 s
->pwprompt
[prompt_len
] = '\0';
6502 "<server failed to send prompt>: ");
6504 s
->echo
= ssh2_pkt_getbool(pktin
);
6510 if (!s
->method
&& s
->can_passwd
) {
6511 s
->method
= AUTH_PASSWORD
;
6512 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6513 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
6514 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
6521 if (!ssh_get_line(s
->pwprompt
, s
->password
,
6522 sizeof(s
->password
), TRUE
)) {
6524 * get_line failed to get a password (for
6525 * example because one was supplied on the
6526 * command line which has already failed to
6529 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6530 ssh2_pkt_adduint32(s
->pktout
,SSH2_DISCONNECT_BY_APPLICATION
);
6531 ssh2_pkt_addstring(s
->pktout
, "No more passwords available"
6533 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6534 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6535 logevent("Unable to authenticate");
6536 connection_fatal(ssh
->frontend
,
6537 "Unable to authenticate");
6538 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6542 int ret
; /* need not be saved across crReturn */
6543 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
6546 setup_userpass_input(ssh
, s
->password
,
6547 sizeof(s
->password
), s
->echo
);
6549 crWaitUntilV(!pktin
);
6550 ret
= process_userpass_input(ssh
, in
, inlen
);
6554 c_write_str(ssh
, "\r\n");
6558 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
6560 * We have our passphrase. Now try the actual authentication.
6562 struct ssh2_userkey
*key
;
6563 const char *error
= NULL
;
6565 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
,
6567 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
6568 if (key
== SSH2_WRONG_PASSPHRASE
) {
6569 c_write_str(ssh
, "Wrong passphrase\r\n");
6570 s
->tried_pubkey_config
= FALSE
;
6572 c_write_str(ssh
, "Unable to load private key (");
6573 c_write_str(ssh
, error
);
6574 c_write_str(ssh
, ")\r\n");
6575 s
->tried_pubkey_config
= TRUE
;
6577 /* Send a spurious AUTH_NONE to return to the top. */
6578 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6579 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6580 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6581 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6582 ssh2_pkt_send(ssh
, s
->pktout
);
6583 s
->type
= AUTH_TYPE_NONE
;
6585 unsigned char *pkblob
, *sigblob
, *sigdata
;
6586 int pkblob_len
, sigblob_len
, sigdata_len
;
6590 * We have loaded the private key and the server
6591 * has announced that it's willing to accept it.
6592 * Hallelujah. Generate a signature and send it.
6594 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6595 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6596 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6597 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6598 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6599 ssh2_pkt_addstring(s
->pktout
, key
->alg
->name
);
6600 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
6601 ssh2_pkt_addstring_start(s
->pktout
);
6602 ssh2_pkt_addstring_data(s
->pktout
, (char *)pkblob
, pkblob_len
);
6605 * The data to be signed is:
6609 * followed by everything so far placed in the
6612 sigdata_len
= s
->pktout
->length
- 5 + 4 + 20;
6613 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6615 sigdata
= snewn(sigdata_len
, unsigned char);
6617 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6618 PUT_32BIT(sigdata
+p
, 20);
6621 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
6622 memcpy(sigdata
+p
, s
->pktout
->data
+ 5,
6623 s
->pktout
->length
- 5);
6624 p
+= s
->pktout
->length
- 5;
6625 assert(p
== sigdata_len
);
6626 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
6627 sigdata_len
, &sigblob_len
);
6628 ssh2_add_sigblob(ssh
, s
->pktout
, pkblob
, pkblob_len
,
6629 sigblob
, sigblob_len
);
6634 ssh2_pkt_send(ssh
, s
->pktout
);
6635 s
->type
= AUTH_TYPE_PUBLICKEY
;
6636 key
->alg
->freekey(key
->data
);
6638 } else if (s
->method
== AUTH_PASSWORD
) {
6640 * We send the password packet lumped tightly together with
6641 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
6642 * string long enough to make the total length of the two
6643 * packets constant. This should ensure that a passive
6644 * listener doing traffic analyis can't work out the length
6647 * For this to work, we need an assumption about the
6648 * maximum length of the password packet. I think 256 is
6649 * pretty conservative. Anyone using a password longer than
6650 * that probably doesn't have much to worry about from
6651 * people who find out how long their password is!
6653 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6654 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6655 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6656 ssh2_pkt_addstring(s
->pktout
, "password");
6657 ssh2_pkt_addbool(s
->pktout
, FALSE
);
6658 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6659 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6660 memset(s
->password
, 0, sizeof(s
->password
));
6661 end_log_omission(ssh
, s
->pktout
);
6662 ssh2_pkt_defer(ssh
, s
->pktout
);
6664 * We'll include a string that's an exact multiple of the
6665 * cipher block size. If the cipher is NULL for some
6666 * reason, we don't do this trick at all because we gain
6669 if (ssh
->cscipher
) {
6672 stringlen
= (256 - ssh
->deferred_len
);
6673 stringlen
+= ssh
->cscipher
->blksize
- 1;
6674 stringlen
-= (stringlen
% ssh
->cscipher
->blksize
);
6677 * Temporarily disable actual compression,
6678 * so we can guarantee to get this string
6679 * exactly the length we want it. The
6680 * compression-disabling routine should
6681 * return an integer indicating how many
6682 * bytes we should adjust our string length
6686 ssh
->cscomp
->disable_compression(ssh
->cs_comp_ctx
);
6688 s
->pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
6689 ssh2_pkt_addstring_start(s
->pktout
);
6690 for (i
= 0; i
< stringlen
; i
++) {
6691 char c
= (char) random_byte();
6692 ssh2_pkt_addstring_data(s
->pktout
, &c
, 1);
6694 ssh2_pkt_defer(ssh
, s
->pktout
);
6696 ssh_pkt_defersend(ssh
);
6697 logevent("Sent password");
6698 s
->type
= AUTH_TYPE_PASSWORD
;
6699 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
6700 if (s
->curr_prompt
== 0) {
6701 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
6702 ssh2_pkt_adduint32(s
->pktout
, s
->num_prompts
);
6704 if (s
->need_pw
) { /* only add pw if we just got one! */
6705 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6706 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6707 memset(s
->password
, 0, sizeof(s
->password
));
6708 end_log_omission(ssh
, s
->pktout
);
6711 if (s
->curr_prompt
>= s
->num_prompts
) {
6712 ssh2_pkt_send(ssh
, s
->pktout
);
6715 * If there are prompts remaining, we set
6716 * `gotit' so that we won't attempt to get
6717 * another packet. Then we go back round the
6718 * loop and will end up retrieving another
6719 * prompt out of the existing packet. Funky or
6724 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6726 c_write_str(ssh
, "No supported authentication methods"
6727 " left to try!\r\n");
6728 logevent("No supported authentications offered."
6730 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6731 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
6732 ssh2_pkt_addstring(s
->pktout
, "No supported authentication"
6733 " methods available");
6734 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6735 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6736 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6740 } while (!s
->we_are_in
);
6743 * Now we're authenticated for the connection protocol. The
6744 * connection protocol will automatically have started at this
6745 * point; there's no need to send SERVICE_REQUEST.
6748 ssh
->channels
= newtree234(ssh_channelcmp
);
6751 * Set up handlers for some connection protocol messages, so we
6752 * don't have to handle them repeatedly in this coroutine.
6754 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] =
6755 ssh2_msg_channel_window_adjust
;
6756 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] =
6757 ssh2_msg_global_request
;
6760 * Create the main session channel.
6762 if (!ssh
->cfg
.ssh_no_shell
) {
6763 ssh
->mainchan
= snew(struct ssh_channel
);
6764 ssh
->mainchan
->ssh
= ssh
;
6765 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
6766 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
6767 ssh2_pkt_addstring(s
->pktout
, "session");
6768 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->localid
);
6769 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6770 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
6771 ssh2_pkt_adduint32(s
->pktout
, 0x4000UL
); /* our max pkt size */
6772 ssh2_pkt_send(ssh
, s
->pktout
);
6773 crWaitUntilV(pktin
);
6774 if (pktin
->type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
6775 bombout(("Server refused to open a session"));
6777 /* FIXME: error data comes back in FAILURE packet */
6779 if (ssh_pkt_getuint32(pktin
) != ssh
->mainchan
->localid
) {
6780 bombout(("Server's channel confirmation cited wrong channel"));
6783 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(pktin
);
6784 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
6785 ssh
->mainchan
->closes
= 0;
6786 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
6787 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
6788 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
6789 add234(ssh
->channels
, ssh
->mainchan
);
6790 update_specials_menu(ssh
->frontend
);
6791 logevent("Opened channel for session");
6793 ssh
->mainchan
= NULL
;
6796 * Now we have a channel, make dispatch table entries for
6797 * general channel-based messages.
6799 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] =
6800 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] =
6801 ssh2_msg_channel_data
;
6802 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = ssh2_msg_channel_eof
;
6803 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = ssh2_msg_channel_close
;
6804 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] =
6805 ssh2_msg_channel_open_confirmation
;
6806 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] =
6807 ssh2_msg_channel_open_failure
;
6808 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] =
6809 ssh2_msg_channel_request
;
6810 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] =
6811 ssh2_msg_channel_open
;
6814 * Potentially enable X11 forwarding.
6816 if (ssh
->mainchan
&& ssh
->cfg
.x11_forward
) {
6817 char proto
[20], data
[64];
6818 logevent("Requesting X11 forwarding");
6819 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
6820 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
6821 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
6822 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6823 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6824 ssh2_pkt_addstring(s
->pktout
, "x11-req");
6825 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6826 ssh2_pkt_addbool(s
->pktout
, 0); /* many connections */
6827 ssh2_pkt_addstring(s
->pktout
, proto
);
6828 ssh2_pkt_addstring(s
->pktout
, data
);
6829 ssh2_pkt_adduint32(s
->pktout
, x11_get_screen_number(ssh
->cfg
.x11_display
));
6830 ssh2_pkt_send(ssh
, s
->pktout
);
6832 crWaitUntilV(pktin
);
6834 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6835 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6836 bombout(("Unexpected response to X11 forwarding request:"
6837 " packet type %d", pktin
->type
));
6840 logevent("X11 forwarding refused");
6842 logevent("X11 forwarding enabled");
6843 ssh
->X11_fwd_enabled
= TRUE
;
6848 * Enable port forwardings.
6850 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
6853 * Potentially enable agent forwarding.
6855 if (ssh
->mainchan
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
6856 logevent("Requesting OpenSSH-style agent forwarding");
6857 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6858 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6859 ssh2_pkt_addstring(s
->pktout
, "auth-agent-req@openssh.com");
6860 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6861 ssh2_pkt_send(ssh
, s
->pktout
);
6863 crWaitUntilV(pktin
);
6865 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6866 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6867 bombout(("Unexpected response to agent forwarding request:"
6868 " packet type %d", pktin
->type
));
6871 logevent("Agent forwarding refused");
6873 logevent("Agent forwarding enabled");
6874 ssh
->agentfwd_enabled
= TRUE
;
6879 * Now allocate a pty for the session.
6881 if (ssh
->mainchan
&& !ssh
->cfg
.nopty
) {
6882 /* Unpick the terminal-speed string. */
6883 /* XXX perhaps we should allow no speeds to be sent. */
6884 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
6885 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
6886 /* Build the pty request. */
6887 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6888 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
6889 ssh2_pkt_addstring(s
->pktout
, "pty-req");
6890 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6891 ssh2_pkt_addstring(s
->pktout
, ssh
->cfg
.termtype
);
6892 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_width
);
6893 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_height
);
6894 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel width */
6895 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel height */
6896 ssh2_pkt_addstring_start(s
->pktout
);
6897 ssh2_pkt_addbyte(s
->pktout
, 128); /* TTY_OP_ISPEED */
6898 ssh2_pkt_adduint32(s
->pktout
, ssh
->ispeed
);
6899 ssh2_pkt_addbyte(s
->pktout
, 129); /* TTY_OP_OSPEED */
6900 ssh2_pkt_adduint32(s
->pktout
, ssh
->ospeed
);
6901 ssh2_pkt_addstring_data(s
->pktout
, "\0", 1); /* TTY_OP_END */
6902 ssh2_pkt_send(ssh
, s
->pktout
);
6903 ssh
->state
= SSH_STATE_INTERMED
;
6905 crWaitUntilV(pktin
);
6907 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6908 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6909 bombout(("Unexpected response to pty request:"
6910 " packet type %d", pktin
->type
));
6913 c_write_str(ssh
, "Server refused to allocate pty\r\n");
6914 ssh
->editing
= ssh
->echoing
= 1;
6916 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
6917 ssh
->ospeed
, ssh
->ispeed
);
6920 ssh
->editing
= ssh
->echoing
= 1;
6924 * Send environment variables.
6926 * Simplest thing here is to send all the requests at once, and
6927 * then wait for a whole bunch of successes or failures.
6929 if (ssh
->mainchan
&& *ssh
->cfg
.environmt
) {
6930 char *e
= ssh
->cfg
.environmt
;
6931 char *var
, *varend
, *val
;
6937 while (*e
&& *e
!= '\t') e
++;
6939 if (*e
== '\t') e
++;
6944 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6945 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6946 ssh2_pkt_addstring(s
->pktout
, "env");
6947 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6948 ssh2_pkt_addstring_start(s
->pktout
);
6949 ssh2_pkt_addstring_data(s
->pktout
, var
, varend
-var
);
6950 ssh2_pkt_addstring(s
->pktout
, val
);
6951 ssh2_pkt_send(ssh
, s
->pktout
);
6956 logeventf(ssh
, "Sent %d environment variables", s
->num_env
);
6959 s
->env_left
= s
->num_env
;
6961 while (s
->env_left
> 0) {
6962 crWaitUntilV(pktin
);
6964 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6965 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6966 bombout(("Unexpected response to environment request:"
6967 " packet type %d", pktin
->type
));
6977 if (s
->env_ok
== s
->num_env
) {
6978 logevent("All environment variables successfully set");
6979 } else if (s
->env_ok
== 0) {
6980 logevent("All environment variables refused");
6981 c_write_str(ssh
, "Server refused to set environment variables\r\n");
6983 logeventf(ssh
, "%d environment variables refused",
6984 s
->num_env
- s
->env_ok
);
6985 c_write_str(ssh
, "Server refused to set all environment variables\r\n");
6990 * Start a shell or a remote command. We may have to attempt
6991 * this twice if the config data has provided a second choice
6994 if (ssh
->mainchan
) while (1) {
6998 if (ssh
->fallback_cmd
) {
6999 subsys
= ssh
->cfg
.ssh_subsys2
;
7000 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
7002 subsys
= ssh
->cfg
.ssh_subsys
;
7003 cmd
= ssh
->cfg
.remote_cmd_ptr
;
7006 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7007 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7009 ssh2_pkt_addstring(s
->pktout
, "subsystem");
7010 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7011 ssh2_pkt_addstring(s
->pktout
, cmd
);
7013 ssh2_pkt_addstring(s
->pktout
, "exec");
7014 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7015 ssh2_pkt_addstring(s
->pktout
, cmd
);
7017 ssh2_pkt_addstring(s
->pktout
, "shell");
7018 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7020 ssh2_pkt_send(ssh
, s
->pktout
);
7022 crWaitUntilV(pktin
);
7024 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7025 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7026 bombout(("Unexpected response to shell/command request:"
7027 " packet type %d", pktin
->type
));
7031 * We failed to start the command. If this is the
7032 * fallback command, we really are finished; if it's
7033 * not, and if the fallback command exists, try falling
7034 * back to it before complaining.
7036 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
7037 logevent("Primary command failed; attempting fallback");
7038 ssh
->fallback_cmd
= TRUE
;
7041 bombout(("Server refused to start a shell/command"));
7044 logevent("Started a shell/command");
7049 ssh
->state
= SSH_STATE_SESSION
;
7050 if (ssh
->size_needed
)
7051 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
7052 if (ssh
->eof_needed
)
7053 ssh_special(ssh
, TS_EOF
);
7059 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
7064 s
->try_send
= FALSE
;
7068 * _All_ the connection-layer packets we expect to
7069 * receive are now handled by the dispatch table.
7070 * Anything that reaches here must be bogus.
7073 bombout(("Strange packet received: type %d", pktin
->type
));
7075 } else if (ssh
->mainchan
) {
7077 * We have spare data. Add it to the channel buffer.
7079 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
7084 struct ssh_channel
*c
;
7086 * Try to send data on all channels if we can.
7088 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
7091 continue; /* don't send on closing channels */
7092 bufsize
= ssh2_try_send(c
);
7095 case CHAN_MAINSESSION
:
7096 /* stdin need not receive an unthrottle
7097 * notification since it will be polled */
7100 x11_unthrottle(c
->u
.x11
.s
);
7103 /* agent sockets are request/response and need no
7104 * buffer management */
7107 pfd_unthrottle(c
->u
.pfd
.s
);
7119 * Handlers for SSH2 messages that might arrive at any moment.
7121 void ssh2_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
7123 /* log reason code in disconnect message */
7125 int nowlen
, reason
, msglen
;
7127 reason
= ssh_pkt_getuint32(pktin
);
7128 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7130 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
7131 buf
= dupprintf("Received disconnect message (%s)",
7132 ssh2_disconnect_reasons
[reason
]);
7134 buf
= dupprintf("Received disconnect message (unknown"
7135 " type %d)", reason
);
7139 buf
= dupprintf("Disconnection message text: %n%.*s",
7140 &nowlen
, msglen
, msg
);
7142 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7144 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
7145 ssh2_disconnect_reasons
[reason
] : "unknown",
7150 void ssh2_msg_debug(Ssh ssh
, struct Packet
*pktin
)
7152 /* log the debug message */
7157 /* XXX maybe we should actually take notice of this */
7158 always_display
= ssh2_pkt_getbool(pktin
);
7159 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7161 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
7166 void ssh2_msg_something_unimplemented(Ssh ssh
, struct Packet
*pktin
)
7168 struct Packet
*pktout
;
7169 pktout
= ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
7170 ssh2_pkt_adduint32(pktout
, pktin
->sequence
);
7172 * UNIMPLEMENTED messages MUST appear in the same order as the
7173 * messages they respond to. Hence, never queue them.
7175 ssh2_pkt_send_noqueue(ssh
, pktout
);
7179 * Handle the top-level SSH2 protocol.
7181 static void ssh2_protocol_setup(Ssh ssh
)
7186 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7188 for (i
= 0; i
< 256; i
++)
7189 ssh
->packet_dispatch
[i
] = ssh2_msg_something_unimplemented
;
7192 * Any message we actually understand, we set to NULL so that
7193 * the coroutines will get it.
7195 ssh
->packet_dispatch
[SSH2_MSG_UNIMPLEMENTED
] = NULL
;
7196 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_REQUEST
] = NULL
;
7197 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_ACCEPT
] = NULL
;
7198 ssh
->packet_dispatch
[SSH2_MSG_KEXINIT
] = NULL
;
7199 ssh
->packet_dispatch
[SSH2_MSG_NEWKEYS
] = NULL
;
7200 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_INIT
] = NULL
;
7201 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_REPLY
] = NULL
;
7202 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7203 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7204 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_INIT
] = NULL
;
7205 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_REPLY
] = NULL
;
7206 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_REQUEST
] = NULL
;
7207 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_FAILURE
] = NULL
;
7208 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_SUCCESS
] = NULL
;
7209 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
7210 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_PK_OK
] = NULL
;
7211 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7212 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7213 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_INFO_RESPONSE
] = NULL
;
7214 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] = NULL
;
7215 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_SUCCESS
] = NULL
;
7216 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_FAILURE
] = NULL
;
7217 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] = NULL
;
7218 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] = NULL
;
7219 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] = NULL
;
7220 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] = NULL
;
7221 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] = NULL
;
7222 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] = NULL
;
7223 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = NULL
;
7224 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = NULL
;
7225 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] = NULL
;
7226 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_SUCCESS
] = NULL
;
7227 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_FAILURE
] = NULL
;
7230 * These special message types we install handlers for.
7232 ssh
->packet_dispatch
[SSH2_MSG_DISCONNECT
] = ssh2_msg_disconnect
;
7233 ssh
->packet_dispatch
[SSH2_MSG_IGNORE
] = ssh_msg_ignore
; /* shared with ssh1 */
7234 ssh
->packet_dispatch
[SSH2_MSG_DEBUG
] = ssh2_msg_debug
;
7237 static void ssh2_timer(void *ctx
, long now
)
7241 if (!ssh
->kex_in_progress
&& ssh
->cfg
.ssh_rekey_time
!= 0 &&
7242 now
- ssh
->next_rekey
>= 0) {
7243 do_ssh2_transport(ssh
, "Initiating key re-exchange (timeout)",
7248 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
7249 struct Packet
*pktin
)
7251 if (ssh
->state
== SSH_STATE_CLOSED
)
7255 ssh
->incoming_data_size
+= pktin
->encrypted_len
;
7256 if (!ssh
->kex_in_progress
&&
7257 ssh
->max_data_size
!= 0 &&
7258 ssh
->incoming_data_size
> ssh
->max_data_size
)
7259 do_ssh2_transport(ssh
, "Initiating key re-exchange "
7260 "(too much data received)", -1, NULL
);
7263 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
7264 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
7268 if (!ssh
->protocol_initial_phase_done
||
7269 (pktin
&& pktin
->type
>= 20 && pktin
->type
< 50)) {
7270 if (do_ssh2_transport(ssh
, in
, inlen
, pktin
) &&
7271 !ssh
->protocol_initial_phase_done
) {
7272 ssh
->protocol_initial_phase_done
= TRUE
;
7274 * Allow authconn to initialise itself.
7276 do_ssh2_authconn(ssh
, NULL
, 0, NULL
);
7279 do_ssh2_authconn(ssh
, in
, inlen
, pktin
);
7284 * Called to set up the connection.
7286 * Returns an error message, or NULL on success.
7288 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
7290 char *host
, int port
, char **realhost
, int nodelay
,
7296 ssh
= snew(struct ssh_tag
);
7297 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7298 ssh
->version
= 0; /* when not ready yet */
7301 ssh
->v1_cipher_ctx
= NULL
;
7302 ssh
->crcda_ctx
= NULL
;
7303 ssh
->cscipher
= NULL
;
7304 ssh
->cs_cipher_ctx
= NULL
;
7305 ssh
->sccipher
= NULL
;
7306 ssh
->sc_cipher_ctx
= NULL
;
7308 ssh
->cs_mac_ctx
= NULL
;
7310 ssh
->sc_mac_ctx
= NULL
;
7312 ssh
->cs_comp_ctx
= NULL
;
7314 ssh
->sc_comp_ctx
= NULL
;
7316 ssh
->kex_ctx
= NULL
;
7317 ssh
->hostkey
= NULL
;
7319 ssh
->state
= SSH_STATE_PREPACKET
;
7320 ssh
->size_needed
= FALSE
;
7321 ssh
->eof_needed
= FALSE
;
7324 ssh
->deferred_send_data
= NULL
;
7325 ssh
->deferred_len
= 0;
7326 ssh
->deferred_size
= 0;
7327 ssh
->fallback_cmd
= 0;
7329 ssh
->x11auth
= NULL
;
7330 ssh
->v1_compressing
= FALSE
;
7331 ssh
->v2_outgoing_sequence
= 0;
7332 ssh
->ssh1_rdpkt_crstate
= 0;
7333 ssh
->ssh2_rdpkt_crstate
= 0;
7334 ssh
->do_ssh_init_crstate
= 0;
7335 ssh
->ssh_gotdata_crstate
= 0;
7336 ssh
->do_ssh1_connection_crstate
= 0;
7337 ssh
->do_ssh1_login_crstate
= 0;
7338 ssh
->do_ssh2_transport_crstate
= 0;
7339 ssh
->do_ssh2_authconn_crstate
= 0;
7340 ssh
->do_ssh_init_state
= NULL
;
7341 ssh
->do_ssh1_login_state
= NULL
;
7342 ssh
->do_ssh2_transport_state
= NULL
;
7343 ssh
->do_ssh2_authconn_state
= NULL
;
7344 ssh
->mainchan
= NULL
;
7345 ssh
->throttled_all
= 0;
7346 ssh
->v1_stdout_throttling
= 0;
7348 ssh
->queuelen
= ssh
->queuesize
= 0;
7349 ssh
->queueing
= FALSE
;
7350 ssh
->qhead
= ssh
->qtail
= NULL
;
7352 *backend_handle
= ssh
;
7355 if (crypto_startup() == 0)
7356 return "Microsoft high encryption pack not installed!";
7359 ssh
->frontend
= frontend_handle
;
7360 ssh
->term_width
= ssh
->cfg
.width
;
7361 ssh
->term_height
= ssh
->cfg
.height
;
7363 ssh
->channels
= NULL
;
7364 ssh
->rportfwds
= NULL
;
7365 ssh
->portfwds
= NULL
;
7370 ssh
->v1_throttle_count
= 0;
7371 ssh
->overall_bufsize
= 0;
7372 ssh
->fallback_cmd
= 0;
7374 ssh
->protocol
= NULL
;
7376 ssh
->protocol_initial_phase_done
= FALSE
;
7380 ssh
->incoming_data_size
= ssh
->outgoing_data_size
=
7381 ssh
->deferred_data_size
= 0L;
7382 ssh
->max_data_size
= parse_blocksize(ssh
->cfg
.ssh_rekey_data
);
7383 ssh
->kex_in_progress
= FALSE
;
7385 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
7394 static void ssh_free(void *handle
)
7396 Ssh ssh
= (Ssh
) handle
;
7397 struct ssh_channel
*c
;
7398 struct ssh_rportfwd
*pf
;
7400 if (ssh
->v1_cipher_ctx
)
7401 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
7402 if (ssh
->cs_cipher_ctx
)
7403 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
7404 if (ssh
->sc_cipher_ctx
)
7405 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
7406 if (ssh
->cs_mac_ctx
)
7407 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
7408 if (ssh
->sc_mac_ctx
)
7409 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
7410 if (ssh
->cs_comp_ctx
) {
7412 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
7414 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
7416 if (ssh
->sc_comp_ctx
) {
7418 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
7420 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
7423 dh_cleanup(ssh
->kex_ctx
);
7424 sfree(ssh
->savedhost
);
7426 while (ssh
->queuelen
-- > 0)
7427 ssh_free_packet(ssh
->queue
[ssh
->queuelen
]);
7430 while (ssh
->qhead
) {
7431 struct queued_handler
*qh
= ssh
->qhead
;
7432 ssh
->qhead
= qh
->next
;
7435 ssh
->qhead
= ssh
->qtail
= NULL
;
7437 if (ssh
->channels
) {
7438 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
7441 if (c
->u
.x11
.s
!= NULL
)
7442 x11_close(c
->u
.x11
.s
);
7445 if (c
->u
.pfd
.s
!= NULL
)
7446 pfd_close(c
->u
.pfd
.s
);
7451 freetree234(ssh
->channels
);
7452 ssh
->channels
= NULL
;
7455 if (ssh
->rportfwds
) {
7456 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
7458 freetree234(ssh
->rportfwds
);
7459 ssh
->rportfwds
= NULL
;
7461 sfree(ssh
->deferred_send_data
);
7463 x11_free_auth(ssh
->x11auth
);
7464 sfree(ssh
->do_ssh_init_state
);
7465 sfree(ssh
->do_ssh1_login_state
);
7466 sfree(ssh
->do_ssh2_transport_state
);
7467 sfree(ssh
->do_ssh2_authconn_state
);
7468 if (ssh
->crcda_ctx
) {
7469 crcda_free_context(ssh
->crcda_ctx
);
7470 ssh
->crcda_ctx
= NULL
;
7474 expire_timer_context(ssh
);
7476 pinger_free(ssh
->pinger
);
7483 * Reconfigure the SSH backend.
7485 static void ssh_reconfig(void *handle
, Config
*cfg
)
7487 Ssh ssh
= (Ssh
) handle
;
7488 char *rekeying
= NULL
;
7489 unsigned long old_max_data_size
;
7491 pinger_reconfig(ssh
->pinger
, &ssh
->cfg
, cfg
);
7492 ssh_setup_portfwd(ssh
, cfg
);
7494 if (ssh
->cfg
.ssh_rekey_time
!= cfg
->ssh_rekey_time
&&
7495 cfg
->ssh_rekey_time
!= 0) {
7496 long new_next
= ssh
->last_rekey
+ cfg
->ssh_rekey_time
*60*TICKSPERSEC
;
7497 long now
= GETTICKCOUNT();
7499 if (new_next
- now
< 0) {
7500 rekeying
= "Initiating key re-exchange (timeout shortened)";
7502 ssh
->next_rekey
= schedule_timer(new_next
- now
, ssh2_timer
, ssh
);
7506 old_max_data_size
= ssh
->max_data_size
;
7507 ssh
->max_data_size
= parse_blocksize(cfg
->ssh_rekey_data
);
7508 if (old_max_data_size
!= ssh
->max_data_size
&&
7509 ssh
->max_data_size
!= 0) {
7510 if (ssh
->outgoing_data_size
> ssh
->max_data_size
||
7511 ssh
->incoming_data_size
> ssh
->max_data_size
)
7512 rekeying
= "Initiating key re-exchange (data limit lowered)";
7515 if (rekeying
&& !ssh
->kex_in_progress
) {
7516 do_ssh2_transport(ssh
, rekeying
, -1, NULL
);
7519 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7523 * Called to send data down the Telnet connection.
7525 static int ssh_send(void *handle
, char *buf
, int len
)
7527 Ssh ssh
= (Ssh
) handle
;
7529 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7532 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
7534 return ssh_sendbuffer(ssh
);
7538 * Called to query the current amount of buffered stdin data.
7540 static int ssh_sendbuffer(void *handle
)
7542 Ssh ssh
= (Ssh
) handle
;
7545 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7549 * If the SSH socket itself has backed up, add the total backup
7550 * size on that to any individual buffer on the stdin channel.
7553 if (ssh
->throttled_all
)
7554 override_value
= ssh
->overall_bufsize
;
7556 if (ssh
->version
== 1) {
7557 return override_value
;
7558 } else if (ssh
->version
== 2) {
7559 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
7560 return override_value
;
7562 return (override_value
+
7563 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
7570 * Called to set the size of the window from SSH's POV.
7572 static void ssh_size(void *handle
, int width
, int height
)
7574 Ssh ssh
= (Ssh
) handle
;
7575 struct Packet
*pktout
;
7577 ssh
->term_width
= width
;
7578 ssh
->term_height
= height
;
7580 switch (ssh
->state
) {
7581 case SSH_STATE_BEFORE_SIZE
:
7582 case SSH_STATE_PREPACKET
:
7583 case SSH_STATE_CLOSED
:
7584 break; /* do nothing */
7585 case SSH_STATE_INTERMED
:
7586 ssh
->size_needed
= TRUE
; /* buffer for later */
7588 case SSH_STATE_SESSION
:
7589 if (!ssh
->cfg
.nopty
) {
7590 if (ssh
->version
== 1) {
7591 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
7592 PKT_INT
, ssh
->term_height
,
7593 PKT_INT
, ssh
->term_width
,
7594 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
7595 } else if (ssh
->mainchan
) {
7596 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7597 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7598 ssh2_pkt_addstring(pktout
, "window-change");
7599 ssh2_pkt_addbool(pktout
, 0);
7600 ssh2_pkt_adduint32(pktout
, ssh
->term_width
);
7601 ssh2_pkt_adduint32(pktout
, ssh
->term_height
);
7602 ssh2_pkt_adduint32(pktout
, 0);
7603 ssh2_pkt_adduint32(pktout
, 0);
7604 ssh2_pkt_send(ssh
, pktout
);
7612 * Return a list of the special codes that make sense in this
7615 static const struct telnet_special
*ssh_get_specials(void *handle
)
7617 static const struct telnet_special ssh1_ignore_special
[] = {
7618 {"IGNORE message", TS_NOP
}
7620 static const struct telnet_special ssh2_transport_specials
[] = {
7621 {"IGNORE message", TS_NOP
},
7622 {"Repeat key exchange", TS_REKEY
},
7624 static const struct telnet_special ssh2_session_specials
[] = {
7627 /* These are the signal names defined by draft-ietf-secsh-connect-23.
7628 * They include all the ISO C signals, but are a subset of the POSIX
7629 * required signals. */
7630 {"SIGINT (Interrupt)", TS_SIGINT
},
7631 {"SIGTERM (Terminate)", TS_SIGTERM
},
7632 {"SIGKILL (Kill)", TS_SIGKILL
},
7633 {"SIGQUIT (Quit)", TS_SIGQUIT
},
7634 {"SIGHUP (Hangup)", TS_SIGHUP
},
7635 {"More signals", TS_SUBMENU
},
7636 {"SIGABRT", TS_SIGABRT
}, {"SIGALRM", TS_SIGALRM
},
7637 {"SIGFPE", TS_SIGFPE
}, {"SIGILL", TS_SIGILL
},
7638 {"SIGPIPE", TS_SIGPIPE
}, {"SIGSEGV", TS_SIGSEGV
},
7639 {"SIGUSR1", TS_SIGUSR1
}, {"SIGUSR2", TS_SIGUSR2
},
7642 static const struct telnet_special specials_end
[] = {
7645 /* XXX review this length for any changes: */
7646 static struct telnet_special ssh_specials
[lenof(ssh2_transport_specials
) +
7647 lenof(ssh2_session_specials
) +
7648 lenof(specials_end
)];
7649 Ssh ssh
= (Ssh
) handle
;
7651 #define ADD_SPECIALS(name) \
7653 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7654 memcpy(&ssh_specials[i], name, sizeof name); \
7658 if (ssh
->version
== 1) {
7659 /* Don't bother offering IGNORE if we've decided the remote
7660 * won't cope with it, since we wouldn't bother sending it if
7662 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7663 ADD_SPECIALS(ssh1_ignore_special
);
7664 } else if (ssh
->version
== 2) {
7665 ADD_SPECIALS(ssh2_transport_specials
);
7667 ADD_SPECIALS(ssh2_session_specials
);
7668 } /* else we're not ready yet */
7671 ADD_SPECIALS(specials_end
);
7672 return ssh_specials
;
7680 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7681 * can send an EOF and collect resulting output (e.g. `plink
7684 static void ssh_special(void *handle
, Telnet_Special code
)
7686 Ssh ssh
= (Ssh
) handle
;
7687 struct Packet
*pktout
;
7689 if (code
== TS_EOF
) {
7690 if (ssh
->state
!= SSH_STATE_SESSION
) {
7692 * Buffer the EOF in case we are pre-SESSION, so we can
7693 * send it as soon as we reach SESSION.
7696 ssh
->eof_needed
= TRUE
;
7699 if (ssh
->version
== 1) {
7700 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
7701 } else if (ssh
->mainchan
) {
7702 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
7703 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7704 ssh2_pkt_send(ssh
, pktout
);
7706 logevent("Sent EOF message");
7707 } else if (code
== TS_PING
|| code
== TS_NOP
) {
7708 if (ssh
->state
== SSH_STATE_CLOSED
7709 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7710 if (ssh
->version
== 1) {
7711 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7712 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
7714 pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
7715 ssh2_pkt_addstring_start(pktout
);
7716 ssh2_pkt_send_noqueue(ssh
, pktout
);
7718 } else if (code
== TS_REKEY
) {
7719 if (!ssh
->kex_in_progress
&& ssh
->version
== 2) {
7720 do_ssh2_transport(ssh
, "Initiating key re-exchange at"
7721 " user request", -1, NULL
);
7723 } else if (code
== TS_BRK
) {
7724 if (ssh
->state
== SSH_STATE_CLOSED
7725 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7726 if (ssh
->version
== 1) {
7727 logevent("Unable to send BREAK signal in SSH1");
7728 } else if (ssh
->mainchan
) {
7729 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7730 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7731 ssh2_pkt_addstring(pktout
, "break");
7732 ssh2_pkt_addbool(pktout
, 0);
7733 ssh2_pkt_adduint32(pktout
, 0); /* default break length */
7734 ssh2_pkt_send(ssh
, pktout
);
7737 /* Is is a POSIX signal? */
7738 char *signame
= NULL
;
7739 if (code
== TS_SIGABRT
) signame
= "ABRT";
7740 if (code
== TS_SIGALRM
) signame
= "ALRM";
7741 if (code
== TS_SIGFPE
) signame
= "FPE";
7742 if (code
== TS_SIGHUP
) signame
= "HUP";
7743 if (code
== TS_SIGILL
) signame
= "ILL";
7744 if (code
== TS_SIGINT
) signame
= "INT";
7745 if (code
== TS_SIGKILL
) signame
= "KILL";
7746 if (code
== TS_SIGPIPE
) signame
= "PIPE";
7747 if (code
== TS_SIGQUIT
) signame
= "QUIT";
7748 if (code
== TS_SIGSEGV
) signame
= "SEGV";
7749 if (code
== TS_SIGTERM
) signame
= "TERM";
7750 if (code
== TS_SIGUSR1
) signame
= "USR1";
7751 if (code
== TS_SIGUSR2
) signame
= "USR2";
7752 /* The SSH-2 protocol does in principle support arbitrary named
7753 * signals, including signame@domain, but we don't support those. */
7755 /* It's a signal. */
7756 if (ssh
->version
== 2 && ssh
->mainchan
) {
7757 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7758 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7759 ssh2_pkt_addstring(pktout
, "signal");
7760 ssh2_pkt_addbool(pktout
, 0);
7761 ssh2_pkt_addstring(pktout
, signame
);
7762 ssh2_pkt_send(ssh
, pktout
);
7763 logeventf(ssh
, "Sent signal SIG%s", signame
);
7766 /* Never heard of it. Do nothing */
7771 void *new_sock_channel(void *handle
, Socket s
)
7773 Ssh ssh
= (Ssh
) handle
;
7774 struct ssh_channel
*c
;
7775 c
= snew(struct ssh_channel
);
7779 c
->remoteid
= -1; /* to be set when open confirmed */
7780 c
->localid
= alloc_channel_id(ssh
);
7782 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
7784 bufchain_init(&c
->v
.v2
.outbuffer
);
7785 add234(ssh
->channels
, c
);
7791 * This is called when stdout/stderr (the entity to which
7792 * from_backend sends data) manages to clear some backlog.
7794 static void ssh_unthrottle(void *handle
, int bufsize
)
7796 Ssh ssh
= (Ssh
) handle
;
7797 if (ssh
->version
== 1) {
7798 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
7799 ssh
->v1_stdout_throttling
= 0;
7800 ssh1_throttle(ssh
, -1);
7803 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
7804 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
7808 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
7810 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
7812 struct Packet
*pktout
;
7814 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
7816 if (ssh
->version
== 1) {
7817 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
7818 PKT_INT
, c
->localid
,
7821 /* PKT_STR, <org:orgport>, */
7824 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
7825 ssh2_pkt_addstring(pktout
, "direct-tcpip");
7826 ssh2_pkt_adduint32(pktout
, c
->localid
);
7827 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7828 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);/* our window size */
7829 ssh2_pkt_adduint32(pktout
, 0x4000UL
); /* our max pkt size */
7830 ssh2_pkt_addstring(pktout
, hostname
);
7831 ssh2_pkt_adduint32(pktout
, port
);
7833 * We make up values for the originator data; partly it's
7834 * too much hassle to keep track, and partly I'm not
7835 * convinced the server should be told details like that
7836 * about my local network configuration.
7838 ssh2_pkt_addstring(pktout
, "client-side-connection");
7839 ssh2_pkt_adduint32(pktout
, 0);
7840 ssh2_pkt_send(ssh
, pktout
);
7844 static Socket
ssh_socket(void *handle
)
7846 Ssh ssh
= (Ssh
) handle
;
7850 static int ssh_sendok(void *handle
)
7852 Ssh ssh
= (Ssh
) handle
;
7853 return ssh
->send_ok
;
7856 static int ssh_ldisc(void *handle
, int option
)
7858 Ssh ssh
= (Ssh
) handle
;
7859 if (option
== LD_ECHO
)
7860 return ssh
->echoing
;
7861 if (option
== LD_EDIT
)
7862 return ssh
->editing
;
7866 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
7868 Ssh ssh
= (Ssh
) handle
;
7872 static void ssh_provide_logctx(void *handle
, void *logctx
)
7874 Ssh ssh
= (Ssh
) handle
;
7875 ssh
->logctx
= logctx
;
7878 static int ssh_return_exitcode(void *handle
)
7880 Ssh ssh
= (Ssh
) handle
;
7884 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
7888 * cfg_info for SSH is the currently running version of the
7889 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
7891 static int ssh_cfg_info(void *handle
)
7893 Ssh ssh
= (Ssh
) handle
;
7894 return ssh
->version
;
7898 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
7899 * that fails. This variable is the means by which scp.c can reach
7900 * into the SSH code and find out which one it got.
7902 extern int ssh_fallback_cmd(void *handle
)
7904 Ssh ssh
= (Ssh
) handle
;
7905 return ssh
->fallback_cmd
;
7908 Backend ssh_backend
= {
7918 ssh_return_exitcode
,