17 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
18 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
19 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
20 #define SSH1_CMSG_USER 4 /* 0x4 */
21 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
22 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
23 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
24 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
25 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
26 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
27 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
28 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
29 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
30 #define SSH1_SMSG_FAILURE 15 /* 0xf */
31 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
32 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
33 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
34 #define SSH1_CMSG_EOF 19 /* 0x13 */
35 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
36 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
37 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
38 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
39 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
40 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
41 #define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
42 #define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
43 #define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
44 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
45 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
46 #define SSH1_MSG_IGNORE 32 /* 0x20 */
47 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
48 #define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
49 #define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
50 #define SSH1_MSG_DEBUG 36 /* 0x24 */
51 #define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
52 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
53 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
54 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
55 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
56 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
57 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
59 #define SSH1_AUTH_TIS 5 /* 0x5 */
60 #define SSH1_AUTH_CCARD 16 /* 0x10 */
62 #define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
63 /* Mask for protoflags we will echo back to server if seen */
64 #define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
66 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
67 #define SSH2_MSG_IGNORE 2 /* 0x2 */
68 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
69 #define SSH2_MSG_DEBUG 4 /* 0x4 */
70 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
71 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
72 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
73 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
74 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
75 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
76 #define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
77 #define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
78 #define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
79 #define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
80 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
81 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
82 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
83 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
84 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
85 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
86 #define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
87 #define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
88 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
89 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
90 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
91 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
92 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
93 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
94 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
95 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
96 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
97 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
98 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
99 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
100 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
101 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
104 * Packet type contexts, so that ssh2_pkt_type can correctly decode
105 * the ambiguous type numbers back into the correct type strings.
107 #define SSH2_PKTCTX_DHGROUP1 0x0001
108 #define SSH2_PKTCTX_DHGEX 0x0002
109 #define SSH2_PKTCTX_PUBLICKEY 0x0010
110 #define SSH2_PKTCTX_PASSWORD 0x0020
111 #define SSH2_PKTCTX_KBDINTER 0x0040
112 #define SSH2_PKTCTX_AUTH_MASK 0x00F0
114 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
115 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
116 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
117 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
118 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
119 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
120 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
121 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
122 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
123 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
124 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
125 #define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
126 #define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
127 #define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
128 #define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
130 static const char *const ssh2_disconnect_reasons
[] = {
132 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
133 "SSH_DISCONNECT_PROTOCOL_ERROR",
134 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
135 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
136 "SSH_DISCONNECT_MAC_ERROR",
137 "SSH_DISCONNECT_COMPRESSION_ERROR",
138 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
139 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
140 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
141 "SSH_DISCONNECT_CONNECTION_LOST",
142 "SSH_DISCONNECT_BY_APPLICATION",
143 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
144 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
145 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
146 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
149 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
150 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
151 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
152 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
154 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
157 * Various remote-bug flags.
159 #define BUG_CHOKES_ON_SSH1_IGNORE 1
160 #define BUG_SSH2_HMAC 2
161 #define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
162 #define BUG_CHOKES_ON_RSA 8
163 #define BUG_SSH2_RSA_PADDING 16
164 #define BUG_SSH2_DERIVEKEY 32
165 #define BUG_SSH2_DH_GEX 64
166 #define BUG_SSH2_PK_SESSIONID 128
168 #define translate(x) if (type == x) return #x
169 #define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
170 static char *ssh1_pkt_type(int type
)
172 translate(SSH1_MSG_DISCONNECT
);
173 translate(SSH1_SMSG_PUBLIC_KEY
);
174 translate(SSH1_CMSG_SESSION_KEY
);
175 translate(SSH1_CMSG_USER
);
176 translate(SSH1_CMSG_AUTH_RSA
);
177 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE
);
178 translate(SSH1_CMSG_AUTH_RSA_RESPONSE
);
179 translate(SSH1_CMSG_AUTH_PASSWORD
);
180 translate(SSH1_CMSG_REQUEST_PTY
);
181 translate(SSH1_CMSG_WINDOW_SIZE
);
182 translate(SSH1_CMSG_EXEC_SHELL
);
183 translate(SSH1_CMSG_EXEC_CMD
);
184 translate(SSH1_SMSG_SUCCESS
);
185 translate(SSH1_SMSG_FAILURE
);
186 translate(SSH1_CMSG_STDIN_DATA
);
187 translate(SSH1_SMSG_STDOUT_DATA
);
188 translate(SSH1_SMSG_STDERR_DATA
);
189 translate(SSH1_CMSG_EOF
);
190 translate(SSH1_SMSG_EXIT_STATUS
);
191 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
);
192 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE
);
193 translate(SSH1_MSG_CHANNEL_DATA
);
194 translate(SSH1_MSG_CHANNEL_CLOSE
);
195 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
);
196 translate(SSH1_SMSG_X11_OPEN
);
197 translate(SSH1_CMSG_PORT_FORWARD_REQUEST
);
198 translate(SSH1_MSG_PORT_OPEN
);
199 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING
);
200 translate(SSH1_SMSG_AGENT_OPEN
);
201 translate(SSH1_MSG_IGNORE
);
202 translate(SSH1_CMSG_EXIT_CONFIRMATION
);
203 translate(SSH1_CMSG_X11_REQUEST_FORWARDING
);
204 translate(SSH1_CMSG_AUTH_RHOSTS_RSA
);
205 translate(SSH1_MSG_DEBUG
);
206 translate(SSH1_CMSG_REQUEST_COMPRESSION
);
207 translate(SSH1_CMSG_AUTH_TIS
);
208 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE
);
209 translate(SSH1_CMSG_AUTH_TIS_RESPONSE
);
210 translate(SSH1_CMSG_AUTH_CCARD
);
211 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE
);
212 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE
);
215 static char *ssh2_pkt_type(int pkt_ctx
, int type
)
217 translate(SSH2_MSG_DISCONNECT
);
218 translate(SSH2_MSG_IGNORE
);
219 translate(SSH2_MSG_UNIMPLEMENTED
);
220 translate(SSH2_MSG_DEBUG
);
221 translate(SSH2_MSG_SERVICE_REQUEST
);
222 translate(SSH2_MSG_SERVICE_ACCEPT
);
223 translate(SSH2_MSG_KEXINIT
);
224 translate(SSH2_MSG_NEWKEYS
);
225 translatec(SSH2_MSG_KEXDH_INIT
, SSH2_PKTCTX_DHGROUP1
);
226 translatec(SSH2_MSG_KEXDH_REPLY
, SSH2_PKTCTX_DHGROUP1
);
227 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST
, SSH2_PKTCTX_DHGEX
);
228 translatec(SSH2_MSG_KEX_DH_GEX_GROUP
, SSH2_PKTCTX_DHGEX
);
229 translatec(SSH2_MSG_KEX_DH_GEX_INIT
, SSH2_PKTCTX_DHGEX
);
230 translatec(SSH2_MSG_KEX_DH_GEX_REPLY
, SSH2_PKTCTX_DHGEX
);
231 translate(SSH2_MSG_USERAUTH_REQUEST
);
232 translate(SSH2_MSG_USERAUTH_FAILURE
);
233 translate(SSH2_MSG_USERAUTH_SUCCESS
);
234 translate(SSH2_MSG_USERAUTH_BANNER
);
235 translatec(SSH2_MSG_USERAUTH_PK_OK
, SSH2_PKTCTX_PUBLICKEY
);
236 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
, SSH2_PKTCTX_PASSWORD
);
237 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST
, SSH2_PKTCTX_KBDINTER
);
238 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE
, SSH2_PKTCTX_KBDINTER
);
239 translate(SSH2_MSG_GLOBAL_REQUEST
);
240 translate(SSH2_MSG_REQUEST_SUCCESS
);
241 translate(SSH2_MSG_REQUEST_FAILURE
);
242 translate(SSH2_MSG_CHANNEL_OPEN
);
243 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
244 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
245 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
246 translate(SSH2_MSG_CHANNEL_DATA
);
247 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA
);
248 translate(SSH2_MSG_CHANNEL_EOF
);
249 translate(SSH2_MSG_CHANNEL_CLOSE
);
250 translate(SSH2_MSG_CHANNEL_REQUEST
);
251 translate(SSH2_MSG_CHANNEL_SUCCESS
);
252 translate(SSH2_MSG_CHANNEL_FAILURE
);
258 #define GET_32BIT(cp) \
259 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
260 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
261 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
262 ((unsigned long)(unsigned char)(cp)[3]))
264 #define PUT_32BIT(cp, value) { \
265 (cp)[0] = (unsigned char)((value) >> 24); \
266 (cp)[1] = (unsigned char)((value) >> 16); \
267 (cp)[2] = (unsigned char)((value) >> 8); \
268 (cp)[3] = (unsigned char)(value); }
270 enum { PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
};
273 * Coroutine mechanics for the sillier bits of the code. If these
274 * macros look impenetrable to you, you might find it helpful to
277 * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
279 * which explains the theory behind these macros.
281 * In particular, if you are getting `case expression not constant'
282 * errors when building with MS Visual Studio, this is because MS's
283 * Edit and Continue debugging feature causes their compiler to
284 * violate ANSI C. To disable Edit and Continue debugging:
286 * - right-click ssh.c in the FileView
288 * - select the C/C++ tab and the General category
289 * - under `Debug info:', select anything _other_ than `Program
290 * Database for Edit and Continue'.
292 #define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
295 if (!ssh->t) ssh->t = snew(struct t); \
297 #define crFinish(z) } *crLine = 0; return (z); }
298 #define crFinishV } *crLine = 0; return; }
299 #define crReturn(z) \
301 *crLine =__LINE__; return (z); case __LINE__:;\
305 *crLine=__LINE__; return; case __LINE__:;\
307 #define crStop(z) do{ *crLine = 0; return (z); }while(0)
308 #define crStopV do{ *crLine = 0; return; }while(0)
309 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
310 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
312 typedef struct ssh_tag
*Ssh
;
314 static void ssh2_pkt_init(Ssh
, int pkt_type
);
315 static void ssh2_pkt_addbool(Ssh
, unsigned char value
);
316 static void ssh2_pkt_adduint32(Ssh
, unsigned long value
);
317 static void ssh2_pkt_addstring_start(Ssh
);
318 static void ssh2_pkt_addstring_str(Ssh
, char *data
);
319 static void ssh2_pkt_addstring_data(Ssh
, char *data
, int len
);
320 static void ssh2_pkt_addstring(Ssh
, char *data
);
321 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
);
322 static void ssh2_pkt_addmp(Ssh
, Bignum b
);
323 static int ssh2_pkt_construct(Ssh
);
324 static void ssh2_pkt_send(Ssh
);
325 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
326 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
329 * Buffer management constants. There are several of these for
330 * various different purposes:
332 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
333 * on a local data stream before we throttle the whole SSH
334 * connection (in SSH1 only). Throttling the whole connection is
335 * pretty drastic so we set this high in the hope it won't
338 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
339 * on the SSH connection itself before we defensively throttle
340 * _all_ local data streams. This is pretty drastic too (though
341 * thankfully unlikely in SSH2 since the window mechanism should
342 * ensure that the server never has any need to throttle its end
343 * of the connection), so we set this high as well.
345 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
349 #define SSH1_BUFFER_LIMIT 32768
350 #define SSH_MAX_BACKLOG 32768
351 #define OUR_V2_WINSIZE 16384
353 const static struct ssh_kex
*kex_algs
[] = {
354 &ssh_diffiehellman_gex
,
358 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
360 static void *nullmac_make_context(void)
364 static void nullmac_free_context(void *handle
)
367 static void nullmac_key(void *handle
, unsigned char *key
)
370 static void nullmac_generate(void *handle
, unsigned char *blk
, int len
,
374 static int nullmac_verify(void *handle
, unsigned char *blk
, int len
,
379 const static struct ssh_mac ssh_mac_none
= {
380 nullmac_make_context
, nullmac_free_context
, nullmac_key
,
381 nullmac_generate
, nullmac_verify
, "none", 0
383 const static struct ssh_mac
*macs
[] = {
384 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
386 const static struct ssh_mac
*buggymacs
[] = {
387 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
390 static void *ssh_comp_none_init(void)
394 static void ssh_comp_none_cleanup(void *handle
)
397 static int ssh_comp_none_block(void *handle
, unsigned char *block
, int len
,
398 unsigned char **outblock
, int *outlen
)
402 static int ssh_comp_none_disable(void *handle
)
406 const static struct ssh_compress ssh_comp_none
= {
408 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
409 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
410 ssh_comp_none_disable
, NULL
412 extern const struct ssh_compress ssh_zlib
;
413 const static struct ssh_compress
*compressions
[] = {
414 &ssh_zlib
, &ssh_comp_none
417 enum { /* channel types */
422 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
426 * 2-3-4 tree storing channels.
429 Ssh ssh
; /* pointer back to main context */
430 unsigned remoteid
, localid
;
433 * In SSH1, this value contains four bits:
435 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
436 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
437 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
438 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
440 * A channel is completely finished with when all four bits are set.
444 struct ssh1_data_channel
{
447 struct ssh2_data_channel
{
449 unsigned remwindow
, remmaxpkt
;
454 struct ssh_agent_channel
{
455 unsigned char *message
;
456 unsigned char msglen
[4];
457 int lensofar
, totallen
;
459 struct ssh_x11_channel
{
462 struct ssh_pfd_channel
{
469 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
470 * 2 use this structure in different ways, reflecting SSH 2's
471 * altogether saner approach to port forwarding.
473 * In SSH 1, you arrange a remote forwarding by sending the server
474 * the remote port number, and the local destination host:port.
475 * When a connection comes in, the server sends you back that
476 * host:port pair, and you connect to it. This is a ready-made
477 * security hole if you're not on the ball: a malicious server
478 * could send you back _any_ host:port pair, so if you trustingly
479 * connect to the address it gives you then you've just opened the
480 * entire inside of your corporate network just by connecting
481 * through it to a dodgy SSH server. Hence, we must store a list of
482 * host:port pairs we _are_ trying to forward to, and reject a
483 * connection request from the server if it's not in the list.
485 * In SSH 2, each side of the connection minds its own business and
486 * doesn't send unnecessary information to the other. You arrange a
487 * remote forwarding by sending the server just the remote port
488 * number. When a connection comes in, the server tells you which
489 * of its ports was connected to; and _you_ have to remember what
490 * local host:port pair went with that port number.
492 * Hence: in SSH 1 this structure stores host:port pairs we intend
493 * to allow connections to, and is indexed by those host:port
494 * pairs. In SSH 2 it stores a mapping from source port to
495 * destination host:port pair, and is indexed by source port.
497 struct ssh_rportfwd
{
498 unsigned sport
, dport
;
511 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
512 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
513 static void ssh_size(void *handle
, int width
, int height
);
514 static void ssh_special(void *handle
, Telnet_Special
);
515 static int ssh2_try_send(struct ssh_channel
*c
);
516 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
517 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
518 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
519 static int ssh_sendbuffer(void *handle
);
520 static void ssh_do_close(Ssh ssh
);
522 struct rdpkt1_state_tag
{
523 long len
, pad
, biglen
, to_read
;
524 unsigned long realcrc
, gotcrc
;
530 struct rdpkt2_state_tag
{
531 long len
, pad
, payload
, packetlen
, maclen
;
534 unsigned long incoming_sequence
;
538 const struct plug_function_table
*fn
;
539 /* the above field _must_ be first in the structure */
541 SHA_State exhash
, exhashbase
;
548 unsigned char session_key
[32];
550 int v1_remote_protoflags
;
551 int v1_local_protoflags
;
552 int agentfwd_enabled
;
555 const struct ssh_cipher
*cipher
;
558 const struct ssh2_cipher
*cscipher
, *sccipher
;
559 void *cs_cipher_ctx
, *sc_cipher_ctx
;
560 const struct ssh_mac
*csmac
, *scmac
;
561 void *cs_mac_ctx
, *sc_mac_ctx
;
562 const struct ssh_compress
*cscomp
, *sccomp
;
563 void *cs_comp_ctx
, *sc_comp_ctx
;
564 const struct ssh_kex
*kex
;
565 const struct ssh_signkey
*hostkey
;
566 unsigned char v2_session_id
[20];
572 int echoing
, editing
;
576 int ospeed
, ispeed
; /* temporaries */
577 int term_width
, term_height
;
579 tree234
*channels
; /* indexed by local id */
580 struct ssh_channel
*mainchan
; /* primary session channel */
587 SSH_STATE_BEFORE_SIZE
,
593 int size_needed
, eof_needed
;
596 struct Packet pktout
;
597 unsigned char *deferred_send_data
;
598 int deferred_len
, deferred_size
;
601 * Gross hack: pscp will try to start SFTP but fall back to
602 * scp1 if that fails. This variable is the means by which
603 * scp.c can reach into the SSH code and find out which one it
609 * Used for username and password input.
611 char *userpass_input_buffer
;
612 int userpass_input_buflen
;
613 int userpass_input_bufpos
;
614 int userpass_input_echo
;
616 char *portfwd_strptr
;
622 int v1_throttle_count
;
625 int v1_stdout_throttling
;
626 int v2_outgoing_sequence
;
628 int ssh1_rdpkt_crstate
;
629 int ssh2_rdpkt_crstate
;
630 int do_ssh_init_crstate
;
631 int ssh_gotdata_crstate
;
632 int ssh1_protocol_crstate
;
633 int do_ssh1_login_crstate
;
634 int do_ssh2_transport_crstate
;
635 int do_ssh2_authconn_crstate
;
637 void *do_ssh_init_state
;
638 void *do_ssh1_login_state
;
639 void *do_ssh2_transport_state
;
640 void *do_ssh2_authconn_state
;
642 struct rdpkt1_state_tag rdpkt1_state
;
643 struct rdpkt2_state_tag rdpkt2_state
;
645 void (*protocol
) (Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
646 int (*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
649 * We maintain a full _copy_ of a Config structure here, not
650 * merely a pointer to it. That way, when we're passed a new
651 * one for reconfiguration, we can check the differences and
652 * potentially reconfigure port forwardings etc in mid-session.
657 * Used to transfer data back from async agent callbacks.
659 void *agent_response
;
660 int agent_response_len
;
663 #define logevent(s) logevent(ssh->frontend, s)
665 /* logevent, only printf-formatted. */
666 static void logeventf(Ssh ssh
, const char *fmt
, ...)
672 buf
= dupvprintf(fmt
, ap
);
678 #define bombout(msg) \
680 char *text = dupprintf msg; \
683 connection_fatal(ssh->frontend, "%s", text); \
687 static int ssh_channelcmp(void *av
, void *bv
)
689 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
690 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
691 if (a
->localid
< b
->localid
)
693 if (a
->localid
> b
->localid
)
697 static int ssh_channelfind(void *av
, void *bv
)
699 unsigned *a
= (unsigned *) av
;
700 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
708 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
710 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
711 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
713 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
714 return i
< 0 ?
-1 : +1;
715 if (a
->dport
> b
->dport
)
717 if (a
->dport
< b
->dport
)
722 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
724 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
725 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
727 if (a
->sport
> b
->sport
)
729 if (a
->sport
< b
->sport
)
734 static int alloc_channel_id(Ssh ssh
)
736 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
737 unsigned low
, high
, mid
;
739 struct ssh_channel
*c
;
742 * First-fit allocation of channel numbers: always pick the
743 * lowest unused one. To do this, binary-search using the
744 * counted B-tree to find the largest channel ID which is in a
745 * contiguous sequence from the beginning. (Precisely
746 * everything in that sequence must have ID equal to its tree
747 * index plus CHANNEL_NUMBER_OFFSET.)
749 tsize
= count234(ssh
->channels
);
753 while (high
- low
> 1) {
754 mid
= (high
+ low
) / 2;
755 c
= index234(ssh
->channels
, mid
);
756 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
757 low
= mid
; /* this one is fine */
759 high
= mid
; /* this one is past it */
762 * Now low points to either -1, or the tree index of the
763 * largest ID in the initial sequence.
766 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
767 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
769 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
772 static void c_write(Ssh ssh
, const char *buf
, int len
)
774 if ((flags
& FLAG_STDERR
)) {
776 for (i
= 0; i
< len
; i
++)
778 fputc(buf
[i
], stderr
);
781 from_backend(ssh
->frontend
, 1, buf
, len
);
784 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
787 for (i
= 0; i
< len
; i
++) {
789 c_write(ssh
, "\r\n", 2);
790 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
791 c_write(ssh
, buf
+ i
, 1);
795 static void c_write_str(Ssh ssh
, const char *buf
)
797 c_write(ssh
, buf
, strlen(buf
));
801 * Collect incoming data in the incoming packet buffer.
802 * Decipher and verify the packet when it is completely read.
803 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
804 * Update the *data and *datalen variables.
805 * Return the additional nr of bytes needed, or 0 when
806 * a complete packet is available.
808 static int ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
810 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
812 crBegin(ssh
->ssh1_rdpkt_crstate
);
817 ssh
->pktin
.length
= 0;
819 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
820 while ((*datalen
) == 0)
822 st
->len
= (st
->len
<< 8) + **data
;
823 (*data
)++, (*datalen
)--;
826 st
->pad
= 8 - (st
->len
% 8);
827 st
->biglen
= st
->len
+ st
->pad
;
828 ssh
->pktin
.length
= st
->len
- 5;
830 if (st
->biglen
< 0) {
831 bombout(("Extremely large packet length from server suggests"
832 " data stream corruption"));
836 if (ssh
->pktin
.maxlen
< st
->biglen
) {
837 ssh
->pktin
.maxlen
= st
->biglen
;
838 ssh
->pktin
.data
= sresize(ssh
->pktin
.data
, st
->biglen
+ APIEXTRA
,
842 st
->to_read
= st
->biglen
;
843 st
->p
= ssh
->pktin
.data
;
844 while (st
->to_read
> 0) {
845 st
->chunk
= st
->to_read
;
846 while ((*datalen
) == 0)
847 crReturn(st
->to_read
);
848 if (st
->chunk
> (*datalen
))
849 st
->chunk
= (*datalen
);
850 memcpy(st
->p
, *data
, st
->chunk
);
852 *datalen
-= st
->chunk
;
854 st
->to_read
-= st
->chunk
;
857 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, ssh
->pktin
.data
,
859 bombout(("Network attack (CRC compensation) detected!"));
864 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, ssh
->pktin
.data
, st
->biglen
);
866 st
->realcrc
= crc32_compute(ssh
->pktin
.data
, st
->biglen
- 4);
867 st
->gotcrc
= GET_32BIT(ssh
->pktin
.data
+ st
->biglen
- 4);
868 if (st
->gotcrc
!= st
->realcrc
) {
869 bombout(("Incorrect CRC received on packet"));
873 ssh
->pktin
.body
= ssh
->pktin
.data
+ st
->pad
+ 1;
874 ssh
->pktin
.savedpos
= 0;
876 if (ssh
->v1_compressing
) {
877 unsigned char *decompblk
;
879 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
880 ssh
->pktin
.body
- 1, ssh
->pktin
.length
+ 1,
881 &decompblk
, &decomplen
)) {
882 bombout(("Zlib decompression encountered invalid data"));
886 if (ssh
->pktin
.maxlen
< st
->pad
+ decomplen
) {
887 ssh
->pktin
.maxlen
= st
->pad
+ decomplen
;
888 ssh
->pktin
.data
= sresize(ssh
->pktin
.data
,
889 ssh
->pktin
.maxlen
+ APIEXTRA
,
891 ssh
->pktin
.body
= ssh
->pktin
.data
+ st
->pad
+ 1;
894 memcpy(ssh
->pktin
.body
- 1, decompblk
, decomplen
);
896 ssh
->pktin
.length
= decomplen
- 1;
899 ssh
->pktin
.type
= ssh
->pktin
.body
[-1];
902 log_packet(ssh
->logctx
,
903 PKT_INCOMING
, ssh
->pktin
.type
,
904 ssh1_pkt_type(ssh
->pktin
.type
),
905 ssh
->pktin
.body
, ssh
->pktin
.length
);
907 if (ssh
->pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
908 ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
||
909 ssh
->pktin
.type
== SSH1_MSG_DEBUG
||
910 ssh
->pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
911 ssh
->pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
912 long stringlen
= GET_32BIT(ssh
->pktin
.body
);
913 if (stringlen
+ 4 != ssh
->pktin
.length
) {
914 bombout(("Received data packet with bogus string length"));
919 if (ssh
->pktin
.type
== SSH1_MSG_DEBUG
) {
920 /* log debug message */
922 int stringlen
= GET_32BIT(ssh
->pktin
.body
);
923 strcpy(buf
, "Remote debug message: ");
926 memcpy(buf
+ 8, ssh
->pktin
.body
+ 4, stringlen
);
927 buf
[8 + stringlen
] = '\0';
930 } else if (ssh
->pktin
.type
== SSH1_MSG_IGNORE
) {
935 if (ssh
->pktin
.type
== SSH1_MSG_DISCONNECT
) {
936 /* log reason code in disconnect message */
938 unsigned msglen
= GET_32BIT(ssh
->pktin
.body
);
940 strcpy(buf
, "Remote sent disconnect: ");
941 nowlen
= strlen(buf
);
942 if (msglen
> sizeof(buf
) - nowlen
- 1)
943 msglen
= sizeof(buf
) - nowlen
- 1;
944 memcpy(buf
+ nowlen
, ssh
->pktin
.body
+ 4, msglen
);
945 buf
[nowlen
+ msglen
] = '\0';
946 /* logevent(buf); (this is now done within the bombout macro) */
947 bombout(("Server sent disconnect message:\n\"%s\"", buf
+nowlen
));
954 static int ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
956 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
958 crBegin(ssh
->ssh2_rdpkt_crstate
);
962 ssh
->pktin
.length
= 0;
964 st
->cipherblk
= ssh
->sccipher
->blksize
;
967 if (st
->cipherblk
< 8)
970 if (ssh
->pktin
.maxlen
< st
->cipherblk
) {
971 ssh
->pktin
.maxlen
= st
->cipherblk
;
972 ssh
->pktin
.data
= sresize(ssh
->pktin
.data
, st
->cipherblk
+ APIEXTRA
,
977 * Acquire and decrypt the first block of the packet. This will
978 * contain the length and padding details.
980 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
981 while ((*datalen
) == 0)
982 crReturn(st
->cipherblk
- st
->i
);
983 ssh
->pktin
.data
[st
->i
] = *(*data
)++;
988 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
989 ssh
->pktin
.data
, st
->cipherblk
);
992 * Now get the length and padding figures.
994 st
->len
= GET_32BIT(ssh
->pktin
.data
);
995 st
->pad
= ssh
->pktin
.data
[4];
998 * _Completely_ silly lengths should be stomped on before they
999 * do us any more damage.
1001 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
1002 bombout(("Incoming packet was garbled on decryption"));
1007 * This enables us to deduce the payload length.
1009 st
->payload
= st
->len
- st
->pad
- 1;
1011 ssh
->pktin
.length
= st
->payload
+ 5;
1014 * So now we can work out the total packet length.
1016 st
->packetlen
= st
->len
+ 4;
1017 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1020 * Adjust memory allocation if packet is too big.
1022 if (ssh
->pktin
.maxlen
< st
->packetlen
+ st
->maclen
) {
1023 ssh
->pktin
.maxlen
= st
->packetlen
+ st
->maclen
;
1024 ssh
->pktin
.data
= sresize(ssh
->pktin
.data
,
1025 ssh
->pktin
.maxlen
+ APIEXTRA
,
1030 * Read and decrypt the remainder of the packet.
1032 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1034 while ((*datalen
) == 0)
1035 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
1036 ssh
->pktin
.data
[st
->i
] = *(*data
)++;
1039 /* Decrypt everything _except_ the MAC. */
1041 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1042 ssh
->pktin
.data
+ st
->cipherblk
,
1043 st
->packetlen
- st
->cipherblk
);
1049 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, ssh
->pktin
.data
, st
->len
+ 4,
1050 st
->incoming_sequence
)) {
1051 bombout(("Incorrect MAC received on packet"));
1054 st
->incoming_sequence
++; /* whether or not we MACed */
1057 * Decompress packet payload.
1060 unsigned char *newpayload
;
1063 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1064 ssh
->pktin
.data
+ 5, ssh
->pktin
.length
- 5,
1065 &newpayload
, &newlen
)) {
1066 if (ssh
->pktin
.maxlen
< newlen
+ 5) {
1067 ssh
->pktin
.maxlen
= newlen
+ 5;
1068 ssh
->pktin
.data
= sresize(ssh
->pktin
.data
,
1069 ssh
->pktin
.maxlen
+ APIEXTRA
,
1072 ssh
->pktin
.length
= 5 + newlen
;
1073 memcpy(ssh
->pktin
.data
+ 5, newpayload
, newlen
);
1078 ssh
->pktin
.savedpos
= 6;
1079 ssh
->pktin
.body
= ssh
->pktin
.data
;
1080 ssh
->pktin
.type
= ssh
->pktin
.data
[5];
1083 log_packet(ssh
->logctx
, PKT_INCOMING
, ssh
->pktin
.type
,
1084 ssh2_pkt_type(ssh
->pkt_ctx
, ssh
->pktin
.type
),
1085 ssh
->pktin
.data
+6, ssh
->pktin
.length
-6);
1087 switch (ssh
->pktin
.type
) {
1089 * These packets we must handle instantly.
1091 case SSH2_MSG_DISCONNECT
:
1093 /* log reason code in disconnect message */
1096 int reason
= GET_32BIT(ssh
->pktin
.data
+ 6);
1097 unsigned msglen
= GET_32BIT(ssh
->pktin
.data
+ 10);
1099 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
1100 buf
= dupprintf("Received disconnect message (%s)",
1101 ssh2_disconnect_reasons
[reason
]);
1103 buf
= dupprintf("Received disconnect message (unknown"
1104 " type %d)", reason
);
1108 buf
= dupprintf("Disconnection message text: %n%.*s",
1109 &nowlen
, msglen
, ssh
->pktin
.data
+ 14);
1111 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
1113 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
1114 ssh2_disconnect_reasons
[reason
] : "unknown",
1120 case SSH2_MSG_IGNORE
:
1122 case SSH2_MSG_DEBUG
:
1124 /* log the debug message */
1126 /* int display = ssh->pktin.body[6]; */
1127 int stringlen
= GET_32BIT(ssh
->pktin
.data
+7);
1129 strcpy(buf
, "Remote debug message: ");
1130 prefix
= strlen(buf
);
1131 if (stringlen
> (int)(sizeof(buf
)-prefix
-1))
1132 stringlen
= sizeof(buf
)-prefix
-1;
1133 memcpy(buf
+ prefix
, ssh
->pktin
.data
+ 11, stringlen
);
1134 buf
[prefix
+ stringlen
] = '\0';
1137 goto next_packet
; /* FIXME: print the debug message */
1140 * These packets we need do nothing about here.
1142 case SSH2_MSG_UNIMPLEMENTED
:
1143 case SSH2_MSG_SERVICE_REQUEST
:
1144 case SSH2_MSG_SERVICE_ACCEPT
:
1145 case SSH2_MSG_KEXINIT
:
1146 case SSH2_MSG_NEWKEYS
:
1147 case SSH2_MSG_KEXDH_INIT
:
1148 case SSH2_MSG_KEXDH_REPLY
:
1149 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1150 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1151 case SSH2_MSG_KEX_DH_GEX_INIT
:
1152 case SSH2_MSG_KEX_DH_GEX_REPLY
:
1153 case SSH2_MSG_USERAUTH_REQUEST
:
1154 case SSH2_MSG_USERAUTH_FAILURE
:
1155 case SSH2_MSG_USERAUTH_SUCCESS
:
1156 case SSH2_MSG_USERAUTH_BANNER
:
1157 case SSH2_MSG_USERAUTH_PK_OK
:
1158 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1159 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1160 case SSH2_MSG_USERAUTH_INFO_RESPONSE
:
1161 case SSH2_MSG_GLOBAL_REQUEST
:
1162 case SSH2_MSG_REQUEST_SUCCESS
:
1163 case SSH2_MSG_REQUEST_FAILURE
:
1164 case SSH2_MSG_CHANNEL_OPEN
:
1165 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
:
1166 case SSH2_MSG_CHANNEL_OPEN_FAILURE
:
1167 case SSH2_MSG_CHANNEL_WINDOW_ADJUST
:
1168 case SSH2_MSG_CHANNEL_DATA
:
1169 case SSH2_MSG_CHANNEL_EXTENDED_DATA
:
1170 case SSH2_MSG_CHANNEL_EOF
:
1171 case SSH2_MSG_CHANNEL_CLOSE
:
1172 case SSH2_MSG_CHANNEL_REQUEST
:
1173 case SSH2_MSG_CHANNEL_SUCCESS
:
1174 case SSH2_MSG_CHANNEL_FAILURE
:
1178 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1181 ssh2_pkt_init(ssh
, SSH2_MSG_UNIMPLEMENTED
);
1182 ssh2_pkt_adduint32(ssh
, st
->incoming_sequence
- 1);
1190 static void ssh1_pktout_size(Ssh ssh
, int len
)
1194 len
+= 5; /* type and CRC */
1195 pad
= 8 - (len
% 8);
1198 ssh
->pktout
.length
= len
- 5;
1199 if (ssh
->pktout
.maxlen
< biglen
) {
1200 ssh
->pktout
.maxlen
= biglen
;
1202 /* Allocate enough buffer space for extra block
1203 * for MS CryptEncrypt() */
1204 ssh
->pktout
.data
= sresize(ssh
->pktout
.data
, biglen
+ 12,
1207 ssh
->pktout
.data
= sresize(ssh
->pktout
.data
, biglen
+ 4,
1211 ssh
->pktout
.body
= ssh
->pktout
.data
+ 4 + pad
+ 1;
1214 static void s_wrpkt_start(Ssh ssh
, int type
, int len
)
1216 ssh1_pktout_size(ssh
, len
);
1217 ssh
->pktout
.type
= type
;
1220 static int s_wrpkt_prepare(Ssh ssh
)
1226 * XXX various versions of SC (including 8.8.4) screw up the
1227 * register allocation in this function and use the same register
1228 * (D6) for len and as a temporary, with predictable results. The
1229 * following sledgehammer prevents this.
1235 ssh
->pktout
.body
[-1] = ssh
->pktout
.type
;
1238 log_packet(ssh
->logctx
, PKT_OUTGOING
, ssh
->pktout
.type
,
1239 ssh1_pkt_type(ssh
->pktout
.type
),
1240 ssh
->pktout
.body
, ssh
->pktout
.length
);
1242 if (ssh
->v1_compressing
) {
1243 unsigned char *compblk
;
1245 zlib_compress_block(ssh
->cs_comp_ctx
,
1246 ssh
->pktout
.body
- 1, ssh
->pktout
.length
+ 1,
1247 &compblk
, &complen
);
1248 ssh1_pktout_size(ssh
, complen
- 1);
1249 memcpy(ssh
->pktout
.body
- 1, compblk
, complen
);
1253 len
= ssh
->pktout
.length
+ 5; /* type and CRC */
1254 pad
= 8 - (len
% 8);
1257 for (i
= 0; i
< pad
; i
++)
1258 ssh
->pktout
.data
[i
+ 4] = random_byte();
1259 crc
= crc32_compute(ssh
->pktout
.data
+ 4, biglen
- 4);
1260 PUT_32BIT(ssh
->pktout
.data
+ biglen
, crc
);
1261 PUT_32BIT(ssh
->pktout
.data
, len
);
1264 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, ssh
->pktout
.data
+ 4, biglen
);
1269 static void s_wrpkt(Ssh ssh
)
1272 len
= s_wrpkt_prepare(ssh
);
1273 backlog
= sk_write(ssh
->s
, (char *)ssh
->pktout
.data
, len
);
1274 if (backlog
> SSH_MAX_BACKLOG
)
1275 ssh_throttle_all(ssh
, 1, backlog
);
1278 static void s_wrpkt_defer(Ssh ssh
)
1281 len
= s_wrpkt_prepare(ssh
);
1282 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1283 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1284 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1288 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, ssh
->pktout
.data
, len
);
1289 ssh
->deferred_len
+= len
;
1293 * Construct a packet with the specified contents.
1295 static void construct_packet(Ssh ssh
, int pkttype
, va_list ap1
, va_list ap2
)
1297 unsigned char *p
, *argp
, argchar
;
1298 unsigned long argint
;
1299 int pktlen
, argtype
, arglen
;
1303 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1306 (void) va_arg(ap1
, int);
1310 (void) va_arg(ap1
, int);
1314 (void) va_arg(ap1
, unsigned char *);
1315 arglen
= va_arg(ap1
, int);
1319 argp
= va_arg(ap1
, unsigned char *);
1320 arglen
= strlen((char *)argp
);
1321 pktlen
+= 4 + arglen
;
1324 bn
= va_arg(ap1
, Bignum
);
1325 pktlen
+= ssh1_bignum_length(bn
);
1332 s_wrpkt_start(ssh
, pkttype
, pktlen
);
1333 p
= ssh
->pktout
.body
;
1335 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1338 argint
= va_arg(ap2
, int);
1339 PUT_32BIT(p
, argint
);
1343 argchar
= (unsigned char) va_arg(ap2
, int);
1348 argp
= va_arg(ap2
, unsigned char *);
1349 arglen
= va_arg(ap2
, int);
1350 memcpy(p
, argp
, arglen
);
1354 argp
= va_arg(ap2
, unsigned char *);
1355 arglen
= strlen((char *)argp
);
1356 PUT_32BIT(p
, arglen
);
1357 memcpy(p
+ 4, argp
, arglen
);
1361 bn
= va_arg(ap2
, Bignum
);
1362 p
+= ssh1_write_bignum(p
, bn
);
1368 static void send_packet(Ssh ssh
, int pkttype
, ...)
1371 va_start(ap1
, pkttype
);
1372 va_start(ap2
, pkttype
);
1373 construct_packet(ssh
, pkttype
, ap1
, ap2
);
1377 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1380 va_start(ap1
, pkttype
);
1381 va_start(ap2
, pkttype
);
1382 construct_packet(ssh
, pkttype
, ap1
, ap2
);
1386 static int ssh_versioncmp(char *a
, char *b
)
1389 unsigned long av
, bv
;
1391 av
= strtoul(a
, &ae
, 10);
1392 bv
= strtoul(b
, &be
, 10);
1394 return (av
< bv ?
-1 : +1);
1399 av
= strtoul(ae
, &ae
, 10);
1400 bv
= strtoul(be
, &be
, 10);
1402 return (av
< bv ?
-1 : +1);
1407 * Utility routines for putting an SSH-protocol `string' and
1408 * `uint32' into a SHA state.
1411 static void sha_string(SHA_State
* s
, void *str
, int len
)
1413 unsigned char lenblk
[4];
1414 PUT_32BIT(lenblk
, len
);
1415 SHA_Bytes(s
, lenblk
, 4);
1416 SHA_Bytes(s
, str
, len
);
1419 static void sha_uint32(SHA_State
* s
, unsigned i
)
1421 unsigned char intblk
[4];
1422 PUT_32BIT(intblk
, i
);
1423 SHA_Bytes(s
, intblk
, 4);
1427 * SSH2 packet construction functions.
1429 static void ssh2_pkt_ensure(Ssh ssh
, int length
)
1431 if (ssh
->pktout
.maxlen
< length
) {
1432 ssh
->pktout
.maxlen
= length
+ 256;
1433 ssh
->pktout
.data
= sresize(ssh
->pktout
.data
,
1434 ssh
->pktout
.maxlen
+ APIEXTRA
,
1436 if (!ssh
->pktout
.data
)
1437 fatalbox("Out of memory");
1440 static void ssh2_pkt_adddata(Ssh ssh
, void *data
, int len
)
1442 ssh
->pktout
.length
+= len
;
1443 ssh2_pkt_ensure(ssh
, ssh
->pktout
.length
);
1444 memcpy(ssh
->pktout
.data
+ ssh
->pktout
.length
- len
, data
, len
);
1446 static void ssh2_pkt_addbyte(Ssh ssh
, unsigned char byte
)
1448 ssh2_pkt_adddata(ssh
, &byte
, 1);
1450 static void ssh2_pkt_init(Ssh ssh
, int pkt_type
)
1452 ssh
->pktout
.length
= 5;
1453 ssh2_pkt_addbyte(ssh
, (unsigned char) pkt_type
);
1455 static void ssh2_pkt_addbool(Ssh ssh
, unsigned char value
)
1457 ssh2_pkt_adddata(ssh
, &value
, 1);
1459 static void ssh2_pkt_adduint32(Ssh ssh
, unsigned long value
)
1462 PUT_32BIT(x
, value
);
1463 ssh2_pkt_adddata(ssh
, x
, 4);
1465 static void ssh2_pkt_addstring_start(Ssh ssh
)
1467 ssh2_pkt_adduint32(ssh
, 0);
1468 ssh
->pktout
.savedpos
= ssh
->pktout
.length
;
1470 static void ssh2_pkt_addstring_str(Ssh ssh
, char *data
)
1472 ssh2_pkt_adddata(ssh
, data
, strlen(data
));
1473 PUT_32BIT(ssh
->pktout
.data
+ ssh
->pktout
.savedpos
- 4,
1474 ssh
->pktout
.length
- ssh
->pktout
.savedpos
);
1476 static void ssh2_pkt_addstring_data(Ssh ssh
, char *data
, int len
)
1478 ssh2_pkt_adddata(ssh
, data
, len
);
1479 PUT_32BIT(ssh
->pktout
.data
+ ssh
->pktout
.savedpos
- 4,
1480 ssh
->pktout
.length
- ssh
->pktout
.savedpos
);
1482 static void ssh2_pkt_addstring(Ssh ssh
, char *data
)
1484 ssh2_pkt_addstring_start(ssh
);
1485 ssh2_pkt_addstring_str(ssh
, data
);
1487 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1490 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1491 p
= snewn(n
+ 1, unsigned char);
1493 fatalbox("out of memory");
1495 for (i
= 1; i
<= n
; i
++)
1496 p
[i
] = bignum_byte(b
, n
- i
);
1498 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1500 memmove(p
, p
+ i
, n
+ 1 - i
);
1504 static void ssh2_pkt_addmp(Ssh ssh
, Bignum b
)
1508 p
= ssh2_mpint_fmt(b
, &len
);
1509 ssh2_pkt_addstring_start(ssh
);
1510 ssh2_pkt_addstring_data(ssh
, (char *)p
, len
);
1515 * Construct an SSH2 final-form packet: compress it, encrypt it,
1516 * put the MAC on it. Final packet, ready to be sent, is stored in
1517 * ssh->pktout.data. Total length is returned.
1519 static int ssh2_pkt_construct(Ssh ssh
)
1521 int cipherblk
, maclen
, padding
, i
;
1524 log_packet(ssh
->logctx
, PKT_OUTGOING
, ssh
->pktout
.data
[5],
1525 ssh2_pkt_type(ssh
->pkt_ctx
, ssh
->pktout
.data
[5]),
1526 ssh
->pktout
.data
+ 6, ssh
->pktout
.length
- 6);
1529 * Compress packet payload.
1532 unsigned char *newpayload
;
1535 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, ssh
->pktout
.data
+ 5,
1536 ssh
->pktout
.length
- 5,
1537 &newpayload
, &newlen
)) {
1538 ssh
->pktout
.length
= 5;
1539 ssh2_pkt_adddata(ssh
, newpayload
, newlen
);
1545 * Add padding. At least four bytes, and must also bring total
1546 * length (minus MAC) up to a multiple of the block size.
1548 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1549 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1552 (cipherblk
- (ssh
->pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
1553 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1554 ssh2_pkt_ensure(ssh
, ssh
->pktout
.length
+ padding
+ maclen
);
1555 ssh
->pktout
.data
[4] = padding
;
1556 for (i
= 0; i
< padding
; i
++)
1557 ssh
->pktout
.data
[ssh
->pktout
.length
+ i
] = random_byte();
1558 PUT_32BIT(ssh
->pktout
.data
, ssh
->pktout
.length
+ padding
- 4);
1560 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, ssh
->pktout
.data
,
1561 ssh
->pktout
.length
+ padding
,
1562 ssh
->v2_outgoing_sequence
);
1563 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1566 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1567 ssh
->pktout
.data
, ssh
->pktout
.length
+ padding
);
1569 /* Ready-to-send packet starts at ssh->pktout.data. We return length. */
1570 return ssh
->pktout
.length
+ padding
+ maclen
;
1574 * Construct and send an SSH2 packet immediately.
1576 static void ssh2_pkt_send(Ssh ssh
)
1580 len
= ssh2_pkt_construct(ssh
);
1581 backlog
= sk_write(ssh
->s
, (char *)ssh
->pktout
.data
, len
);
1582 if (backlog
> SSH_MAX_BACKLOG
)
1583 ssh_throttle_all(ssh
, 1, backlog
);
1587 * Construct an SSH2 packet and add it to a deferred data block.
1588 * Useful for sending multiple packets in a single sk_write() call,
1589 * to prevent a traffic-analysing listener from being able to work
1590 * out the length of any particular packet (such as the password
1593 * Note that because SSH2 sequence-numbers its packets, this can
1594 * NOT be used as an m4-style `defer' allowing packets to be
1595 * constructed in one order and sent in another.
1597 static void ssh2_pkt_defer(Ssh ssh
)
1599 int len
= ssh2_pkt_construct(ssh
);
1600 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1601 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1602 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1606 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, ssh
->pktout
.data
, len
);
1607 ssh
->deferred_len
+= len
;
1611 * Send the whole deferred data block constructed by
1612 * ssh2_pkt_defer() or SSH1's defer_packet().
1614 static void ssh_pkt_defersend(Ssh ssh
)
1617 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1619 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1620 sfree(ssh
->deferred_send_data
);
1621 ssh
->deferred_send_data
= NULL
;
1622 if (backlog
> SSH_MAX_BACKLOG
)
1623 ssh_throttle_all(ssh
, 1, backlog
);
1627 void bndebug(char *string
, Bignum b
)
1631 p
= ssh2_mpint_fmt(b
, &len
);
1632 debug(("%s", string
));
1633 for (i
= 0; i
< len
; i
++)
1634 debug((" %02x", p
[i
]));
1640 static void sha_mpint(SHA_State
* s
, Bignum b
)
1644 p
= ssh2_mpint_fmt(b
, &len
);
1645 sha_string(s
, p
, len
);
1650 * Packet decode functions for both SSH1 and SSH2.
1652 static unsigned long ssh_pkt_getuint32(Ssh ssh
)
1654 unsigned long value
;
1655 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< 4)
1656 return 0; /* arrgh, no way to decline (FIXME?) */
1657 value
= GET_32BIT(ssh
->pktin
.body
+ ssh
->pktin
.savedpos
);
1658 ssh
->pktin
.savedpos
+= 4;
1661 static int ssh2_pkt_getbool(Ssh ssh
)
1663 unsigned long value
;
1664 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< 1)
1665 return 0; /* arrgh, no way to decline (FIXME?) */
1666 value
= ssh
->pktin
.body
[ssh
->pktin
.savedpos
] != 0;
1667 ssh
->pktin
.savedpos
++;
1670 static void ssh_pkt_getstring(Ssh ssh
, char **p
, int *length
)
1675 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< 4)
1677 len
= GET_32BIT(ssh
->pktin
.body
+ ssh
->pktin
.savedpos
);
1681 ssh
->pktin
.savedpos
+= 4;
1682 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< *length
)
1684 *p
= (char *)(ssh
->pktin
.body
+ ssh
->pktin
.savedpos
);
1685 ssh
->pktin
.savedpos
+= *length
;
1687 static void *ssh_pkt_getdata(Ssh ssh
, int length
)
1689 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< length
)
1691 ssh
->pktin
.savedpos
+= length
;
1692 return ssh
->pktin
.body
+ (ssh
->pktin
.savedpos
- length
);
1694 static int ssh1_pkt_getrsakey(Ssh ssh
, struct RSAKey
*key
,
1695 unsigned char **keystr
)
1699 j
= makekey(ssh
->pktin
.body
+ ssh
->pktin
.savedpos
,
1700 ssh
->pktin
.length
- ssh
->pktin
.savedpos
,
1706 ssh
->pktin
.savedpos
+= j
;
1707 assert(ssh
->pktin
.savedpos
< ssh
->pktin
.length
);
1711 static Bignum
ssh1_pkt_getmp(Ssh ssh
)
1716 j
= ssh1_read_bignum(ssh
->pktin
.body
+ ssh
->pktin
.savedpos
,
1717 ssh
->pktin
.length
- ssh
->pktin
.savedpos
, &b
);
1722 ssh
->pktin
.savedpos
+= j
;
1725 static Bignum
ssh2_pkt_getmp(Ssh ssh
)
1731 ssh_pkt_getstring(ssh
, &p
, &length
);
1735 bombout(("internal error: Can't handle negative mpints"));
1738 b
= bignum_from_bytes((unsigned char *)p
, length
);
1743 * Helper function to add an SSH2 signature blob to a packet.
1744 * Expects to be shown the public key blob as well as the signature
1745 * blob. Normally works just like ssh2_pkt_addstring, but will
1746 * fiddle with the signature packet if necessary for
1747 * BUG_SSH2_RSA_PADDING.
1749 static void ssh2_add_sigblob(Ssh ssh
, void *pkblob_v
, int pkblob_len
,
1750 void *sigblob_v
, int sigblob_len
)
1752 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1753 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1755 /* dmemdump(pkblob, pkblob_len); */
1756 /* dmemdump(sigblob, sigblob_len); */
1759 * See if this is in fact an ssh-rsa signature and a buggy
1760 * server; otherwise we can just do this the easy way.
1762 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1763 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1764 int pos
, len
, siglen
;
1767 * Find the byte length of the modulus.
1770 pos
= 4+7; /* skip over "ssh-rsa" */
1771 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1772 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
1773 pos
+= 4; /* find modulus itself */
1774 while (len
> 0 && pkblob
[pos
] == 0)
1776 /* debug(("modulus length is %d\n", len)); */
1779 * Now find the signature integer.
1781 pos
= 4+7; /* skip over "ssh-rsa" */
1782 siglen
= GET_32BIT(sigblob
+pos
);
1783 /* debug(("signature length is %d\n", siglen)); */
1785 if (len
!= siglen
) {
1786 unsigned char newlen
[4];
1787 ssh2_pkt_addstring_start(ssh
);
1788 ssh2_pkt_addstring_data(ssh
, (char *)sigblob
, pos
);
1789 /* dmemdump(sigblob, pos); */
1790 pos
+= 4; /* point to start of actual sig */
1791 PUT_32BIT(newlen
, len
);
1792 ssh2_pkt_addstring_data(ssh
, (char *)newlen
, 4);
1793 /* dmemdump(newlen, 4); */
1795 while (len
-- > siglen
) {
1796 ssh2_pkt_addstring_data(ssh
, (char *)newlen
, 1);
1797 /* dmemdump(newlen, 1); */
1799 ssh2_pkt_addstring_data(ssh
, (char *)(sigblob
+pos
), siglen
);
1800 /* dmemdump(sigblob+pos, siglen); */
1804 /* Otherwise fall through and do it the easy way. */
1807 ssh2_pkt_addstring_start(ssh
);
1808 ssh2_pkt_addstring_data(ssh
, (char *)sigblob
, sigblob_len
);
1812 * Examine the remote side's version string and compare it against
1813 * a list of known buggy implementations.
1815 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
1817 char *imp
; /* pointer to implementation part */
1819 imp
+= strcspn(imp
, "-");
1821 imp
+= strcspn(imp
, "-");
1824 ssh
->remote_bugs
= 0;
1826 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
1827 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
1828 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
1829 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
1830 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
1831 !strcmp(imp
, "OSU_1.4alpha3")))) {
1833 * These versions don't support SSH1_MSG_IGNORE, so we have
1834 * to use a different defence against password length
1837 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
1838 logevent("We believe remote version has SSH1 ignore bug");
1841 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
1842 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
1843 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
1845 * These versions need a plain password sent; they can't
1846 * handle having a null and a random length of data after
1849 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
1850 logevent("We believe remote version needs a plain SSH1 password");
1853 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
1854 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
1855 (!strcmp(imp
, "Cisco-1.25")))) {
1857 * These versions apparently have no clue whatever about
1858 * RSA authentication and will panic and die if they see
1859 * an AUTH_RSA message.
1861 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
1862 logevent("We believe remote version can't handle RSA authentication");
1865 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
1866 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
1867 !wc_match("* VShell", imp
) &&
1868 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
1869 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
1870 wc_match("2.1 *", imp
)))) {
1872 * These versions have the HMAC bug.
1874 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
1875 logevent("We believe remote version has SSH2 HMAC bug");
1878 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
1879 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
1880 !wc_match("* VShell", imp
) &&
1881 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
1883 * These versions have the key-derivation bug (failing to
1884 * include the literal shared secret in the hashes that
1885 * generate the keys).
1887 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
1888 logevent("We believe remote version has SSH2 key-derivation bug");
1891 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
1892 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
1893 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
1894 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
1896 * These versions have the SSH2 RSA padding bug.
1898 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
1899 logevent("We believe remote version has SSH2 RSA padding bug");
1902 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
1903 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
1904 wc_match("OpenSSH_2.[0-2]*", imp
))) {
1906 * These versions have the SSH2 session-ID bug in
1907 * public-key authentication.
1909 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
1910 logevent("We believe remote version has SSH2 public-key-session-ID bug");
1913 if (ssh
->cfg
.sshbug_dhgex2
== FORCE_ON
) {
1915 * User specified the SSH2 DH GEX bug.
1917 ssh
->remote_bugs
|= BUG_SSH2_DH_GEX
;
1918 logevent("We believe remote version has SSH2 DH group exchange bug");
1922 static int do_ssh_init(Ssh ssh
, unsigned char c
)
1924 struct do_ssh_init_state
{
1932 crState(do_ssh_init_state
);
1934 crBegin(ssh
->do_ssh_init_crstate
);
1936 /* Search for the string "SSH-" in the input. */
1939 static const int transS
[] = { 1, 2, 2, 1 };
1940 static const int transH
[] = { 0, 0, 3, 0 };
1941 static const int transminus
[] = { 0, 0, 0, -1 };
1943 s
->i
= transS
[s
->i
];
1945 s
->i
= transH
[s
->i
];
1947 s
->i
= transminus
[s
->i
];
1952 crReturn(1); /* get another character */
1956 s
->vstring
= snewn(s
->vstrsize
, char);
1957 strcpy(s
->vstring
, "SSH-");
1961 crReturn(1); /* get another char */
1962 if (s
->vslen
>= s
->vstrsize
- 1) {
1964 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
1966 s
->vstring
[s
->vslen
++] = c
;
1969 s
->version
[s
->i
] = '\0';
1971 } else if (s
->i
< sizeof(s
->version
) - 1)
1972 s
->version
[s
->i
++] = c
;
1973 } else if (c
== '\012')
1977 ssh
->agentfwd_enabled
= FALSE
;
1978 ssh
->rdpkt2_state
.incoming_sequence
= 0;
1980 s
->vstring
[s
->vslen
] = 0;
1981 s
->vstring
[strcspn(s
->vstring
, "\r\n")] = '\0';/* remove EOL chars */
1984 vlog
= snewn(20 + s
->vslen
, char);
1985 sprintf(vlog
, "Server version: %s", s
->vstring
);
1989 ssh_detect_bugs(ssh
, s
->vstring
);
1992 * Decide which SSH protocol version to support.
1995 /* Anything strictly below "2.0" means protocol 1 is supported. */
1996 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
1997 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
1998 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2000 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2001 bombout(("SSH protocol version 1 required by user but not provided by server"));
2004 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2005 bombout(("SSH protocol version 2 required by user but not provided by server"));
2009 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2013 char verstring
[80], vlog
[100];
2014 sprintf(verstring
, "SSH-2.0-%s", sshver
);
2015 SHA_Init(&ssh
->exhashbase
);
2017 * Hash our version string and their version string.
2019 sha_string(&ssh
->exhashbase
, verstring
, strlen(verstring
));
2020 sha_string(&ssh
->exhashbase
, s
->vstring
, strcspn(s
->vstring
, "\r\n"));
2021 sprintf(vlog
, "We claim version: %s", verstring
);
2023 strcat(verstring
, "\012");
2024 logevent("Using SSH protocol version 2");
2025 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2026 ssh
->protocol
= ssh2_protocol
;
2028 ssh
->s_rdpkt
= ssh2_rdpkt
;
2033 char verstring
[80], vlog
[100];
2034 sprintf(verstring
, "SSH-%s-%s",
2035 (ssh_versioncmp(s
->version
, "1.5") <= 0 ? s
->version
: "1.5"),
2037 sprintf(vlog
, "We claim version: %s", verstring
);
2039 strcat(verstring
, "\012");
2041 logevent("Using SSH protocol version 1");
2042 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2043 ssh
->protocol
= ssh1_protocol
;
2045 ssh
->s_rdpkt
= ssh1_rdpkt
;
2047 update_specials_menu(ssh
->frontend
);
2048 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2055 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2057 crBegin(ssh
->ssh_gotdata_crstate
);
2060 * To begin with, feed the characters one by one to the
2061 * protocol initialisation / selection function do_ssh_init().
2062 * When that returns 0, we're done with the initial greeting
2063 * exchange and can move on to packet discipline.
2066 int ret
; /* need not be kept across crReturn */
2068 crReturnV
; /* more data please */
2069 ret
= do_ssh_init(ssh
, *data
);
2077 * We emerge from that loop when the initial negotiation is
2078 * over and we have selected an s_rdpkt function. Now pass
2079 * everything to s_rdpkt, and then pass the resulting packets
2080 * to the proper protocol handler.
2085 while (datalen
> 0) {
2086 if (ssh
->s_rdpkt(ssh
, &data
, &datalen
) == 0) {
2087 if (ssh
->state
== SSH_STATE_CLOSED
) {
2090 ssh
->protocol(ssh
, NULL
, 0, 1);
2091 if (ssh
->state
== SSH_STATE_CLOSED
) {
2101 static void ssh_do_close(Ssh ssh
)
2104 struct ssh_channel
*c
;
2106 ssh
->state
= SSH_STATE_CLOSED
;
2112 * Now we must shut down any port and X forwardings going
2113 * through this connection.
2115 if (ssh
->channels
) {
2116 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2119 x11_close(c
->u
.x11
.s
);
2122 pfd_close(c
->u
.pfd
.s
);
2125 del234(ssh
->channels
, c
);
2126 if (ssh
->version
== 2)
2127 bufchain_clear(&c
->v
.v2
.outbuffer
);
2133 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2136 Ssh ssh
= (Ssh
) plug
;
2139 /* A socket error has occurred. */
2140 logevent(error_msg
);
2141 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2143 /* Otherwise, the remote side closed the connection normally. */
2148 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2150 Ssh ssh
= (Ssh
) plug
;
2151 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2152 if (ssh
->state
== SSH_STATE_CLOSED
) {
2159 static void ssh_sent(Plug plug
, int bufsize
)
2161 Ssh ssh
= (Ssh
) plug
;
2163 * If the send backlog on the SSH socket itself clears, we
2164 * should unthrottle the whole world if it was throttled.
2166 if (bufsize
< SSH_MAX_BACKLOG
)
2167 ssh_throttle_all(ssh
, 0, bufsize
);
2171 * Connect to specified host and port.
2172 * Returns an error message, or NULL on success.
2173 * Also places the canonical host name into `realhost'. It must be
2174 * freed by the caller.
2176 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2177 char **realhost
, int nodelay
, int keepalive
)
2179 static const struct plug_function_table fn_table
= {
2189 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2190 if (!ssh
->savedhost
)
2191 fatalbox("Out of memory");
2192 strcpy(ssh
->savedhost
, host
);
2195 port
= 22; /* default ssh port */
2196 ssh
->savedport
= port
;
2201 logeventf(ssh
, "Looking up host \"%s\"", host
);
2202 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
);
2203 if ((err
= sk_addr_error(addr
)) != NULL
) {
2213 sk_getaddr(addr
, addrbuf
, 100);
2214 logeventf(ssh
, "Connecting to %s port %d", addrbuf
, port
);
2216 ssh
->fn
= &fn_table
;
2217 ssh
->s
= new_connection(addr
, *realhost
, port
,
2218 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2219 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2228 * Throttle or unthrottle the SSH connection.
2230 static void ssh1_throttle(Ssh ssh
, int adjust
)
2232 int old_count
= ssh
->v1_throttle_count
;
2233 ssh
->v1_throttle_count
+= adjust
;
2234 assert(ssh
->v1_throttle_count
>= 0);
2235 if (ssh
->v1_throttle_count
&& !old_count
) {
2236 sk_set_frozen(ssh
->s
, 1);
2237 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2238 sk_set_frozen(ssh
->s
, 0);
2243 * Throttle or unthrottle _all_ local data streams (for when sends
2244 * on the SSH connection itself back up).
2246 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2249 struct ssh_channel
*c
;
2251 if (enable
== ssh
->throttled_all
)
2253 ssh
->throttled_all
= enable
;
2254 ssh
->overall_bufsize
= bufsize
;
2257 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2259 case CHAN_MAINSESSION
:
2261 * This is treated separately, outside the switch.
2265 x11_override_throttle(c
->u
.x11
.s
, enable
);
2268 /* Agent channels require no buffer management. */
2271 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2278 * Username and password input, abstracted off into routines
2279 * reusable in several places - even between SSH1 and SSH2.
2282 /* Set up a username or password input loop on a given buffer. */
2283 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2285 ssh
->userpass_input_buffer
= buffer
;
2286 ssh
->userpass_input_buflen
= buflen
;
2287 ssh
->userpass_input_bufpos
= 0;
2288 ssh
->userpass_input_echo
= echo
;
2292 * Process some terminal data in the course of username/password
2293 * input. Returns >0 for success (line of input returned in
2294 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2295 * for inconclusive (keep waiting for more input please).
2297 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2302 switch (c
= *in
++) {
2305 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2306 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2311 if (ssh
->userpass_input_bufpos
> 0) {
2312 if (ssh
->userpass_input_echo
)
2313 c_write_str(ssh
, "\b \b");
2314 ssh
->userpass_input_bufpos
--;
2319 while (ssh
->userpass_input_bufpos
> 0) {
2320 if (ssh
->userpass_input_echo
)
2321 c_write_str(ssh
, "\b \b");
2322 ssh
->userpass_input_bufpos
--;
2331 * This simplistic check for printability is disabled
2332 * when we're doing password input, because some people
2333 * have control characters in their passwords.o
2335 if ((!ssh
->userpass_input_echo
||
2336 (c
>= ' ' && c
<= '~') ||
2337 ((unsigned char) c
>= 160))
2338 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2339 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2340 if (ssh
->userpass_input_echo
)
2341 c_write(ssh
, &c
, 1);
2349 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2351 Ssh ssh
= (Ssh
) sshv
;
2353 ssh
->agent_response
= reply
;
2354 ssh
->agent_response_len
= replylen
;
2356 if (ssh
->version
== 1)
2357 do_ssh1_login(ssh
, NULL
, -1, 0);
2359 do_ssh2_authconn(ssh
, NULL
, -1, 0);
2362 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2364 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2366 void *sentreply
= reply
;
2369 /* Fake SSH_AGENT_FAILURE. */
2370 sentreply
= "\0\0\0\1\5";
2373 if (ssh
->version
== 2) {
2374 ssh2_add_channel_data(c
, sentreply
, replylen
);
2377 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2378 PKT_INT
, c
->remoteid
,
2380 PKT_DATA
, sentreply
, replylen
,
2388 * Handle the key exchange and user authentication phases.
2390 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
2393 unsigned char cookie
[8], *ptr
;
2394 struct RSAKey servkey
, hostkey
;
2395 struct MD5Context md5c
;
2396 struct do_ssh1_login_state
{
2398 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2399 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2400 int tried_publickey
, tried_agent
;
2401 int tis_auth_refused
, ccard_auth_refused
;
2402 unsigned char session_id
[16];
2405 void *publickey_blob
;
2406 int publickey_bloblen
;
2412 unsigned char request
[5], *response
, *p
;
2421 crState(do_ssh1_login_state
);
2423 crBegin(ssh
->do_ssh1_login_crstate
);
2428 if (ssh
->pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
2429 bombout(("Public key packet not received"));
2433 logevent("Received public keys");
2435 ptr
= ssh_pkt_getdata(ssh
, 8);
2437 bombout(("SSH1 public key packet stopped before random cookie"));
2440 memcpy(cookie
, ptr
, 8);
2442 if (!ssh1_pkt_getrsakey(ssh
, &servkey
, &s
->keystr1
) ||
2443 !ssh1_pkt_getrsakey(ssh
, &hostkey
, &s
->keystr2
)) {
2444 bombout(("Failed to read SSH1 public keys from public key packet"));
2449 * Log the host key fingerprint.
2453 logevent("Host key fingerprint is:");
2454 strcpy(logmsg
, " ");
2455 hostkey
.comment
= NULL
;
2456 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2457 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2461 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(ssh
);
2462 s
->supported_ciphers_mask
= ssh_pkt_getuint32(ssh
);
2463 s
->supported_auths_mask
= ssh_pkt_getuint32(ssh
);
2465 ssh
->v1_local_protoflags
=
2466 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2467 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2470 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2471 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2472 MD5Update(&md5c
, cookie
, 8);
2473 MD5Final(s
->session_id
, &md5c
);
2475 for (i
= 0; i
< 32; i
++)
2476 ssh
->session_key
[i
] = random_byte();
2479 * Verify that the `bits' and `bytes' parameters match.
2481 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
2482 servkey
.bits
> servkey
.bytes
* 8) {
2483 bombout(("SSH1 public keys were badly formatted"));
2487 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2489 s
->rsabuf
= snewn(s
->len
, unsigned char);
2491 fatalbox("Out of memory");
2494 * Verify the host key.
2498 * First format the key into a string.
2500 int len
= rsastr_len(&hostkey
);
2501 char fingerprint
[100];
2502 char *keystr
= snewn(len
, char);
2504 fatalbox("Out of memory");
2505 rsastr_fmt(keystr
, &hostkey
);
2506 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2507 verify_ssh_host_key(ssh
->frontend
,
2508 ssh
->savedhost
, ssh
->savedport
, "rsa", keystr
,
2513 for (i
= 0; i
< 32; i
++) {
2514 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2516 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2519 if (hostkey
.bytes
> servkey
.bytes
) {
2520 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
2522 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2524 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2526 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2529 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2533 logevent("Encrypted session key");
2536 int cipher_chosen
= 0, warn
= 0;
2537 char *cipher_string
= NULL
;
2539 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2540 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
2541 if (next_cipher
== CIPHER_WARN
) {
2542 /* If/when we choose a cipher, warn about it */
2544 } else if (next_cipher
== CIPHER_AES
) {
2545 /* XXX Probably don't need to mention this. */
2546 logevent("AES not supported in SSH1, skipping");
2548 switch (next_cipher
) {
2549 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2550 cipher_string
= "3DES"; break;
2551 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2552 cipher_string
= "Blowfish"; break;
2553 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2554 cipher_string
= "single-DES"; break;
2556 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2560 if (!cipher_chosen
) {
2561 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2562 bombout(("Server violates SSH 1 protocol by not "
2563 "supporting 3DES encryption"));
2565 /* shouldn't happen */
2566 bombout(("No supported ciphers found"));
2570 /* Warn about chosen cipher if necessary. */
2572 askcipher(ssh
->frontend
, cipher_string
, 0);
2575 switch (s
->cipher_type
) {
2576 case SSH_CIPHER_3DES
:
2577 logevent("Using 3DES encryption");
2579 case SSH_CIPHER_DES
:
2580 logevent("Using single-DES encryption");
2582 case SSH_CIPHER_BLOWFISH
:
2583 logevent("Using Blowfish encryption");
2587 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
2588 PKT_CHAR
, s
->cipher_type
,
2589 PKT_DATA
, cookie
, 8,
2590 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
2591 PKT_DATA
, s
->rsabuf
, s
->len
,
2592 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
2594 logevent("Trying to enable encryption...");
2598 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2599 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
2601 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
2602 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
2603 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
2605 ssh
->crcda_ctx
= crcda_make_context();
2606 logevent("Installing CRC compensation attack detector");
2608 if (servkey
.modulus
) {
2609 sfree(servkey
.modulus
);
2610 servkey
.modulus
= NULL
;
2612 if (servkey
.exponent
) {
2613 sfree(servkey
.exponent
);
2614 servkey
.exponent
= NULL
;
2616 if (hostkey
.modulus
) {
2617 sfree(hostkey
.modulus
);
2618 hostkey
.modulus
= NULL
;
2620 if (hostkey
.exponent
) {
2621 sfree(hostkey
.exponent
);
2622 hostkey
.exponent
= NULL
;
2626 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2627 bombout(("Encryption not successfully enabled"));
2631 logevent("Successfully started encryption");
2635 if ((flags
& FLAG_INTERACTIVE
) && !*ssh
->cfg
.username
) {
2636 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2637 if (!ssh_get_line("login as: ",
2638 s
->username
, sizeof(s
->username
), FALSE
)) {
2640 * get_line failed to get a username.
2643 logevent("No username provided. Abandoning session.");
2644 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2648 int ret
; /* need not be kept over crReturn */
2649 c_write_str(ssh
, "login as: ");
2652 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
2654 crWaitUntil(!ispkt
);
2655 ret
= process_userpass_input(ssh
, in
, inlen
);
2659 c_write_str(ssh
, "\r\n");
2662 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
2663 s
->username
[sizeof(s
->username
)-1] = '\0';
2666 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
2668 char userlog
[22 + sizeof(s
->username
)];
2669 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
2671 if (flags
& FLAG_INTERACTIVE
&&
2672 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2673 strcat(userlog
, "\r\n");
2674 c_write_str(ssh
, userlog
);
2681 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2682 /* We must not attempt PK auth. Pretend we've already tried it. */
2683 s
->tried_publickey
= s
->tried_agent
= 1;
2685 s
->tried_publickey
= s
->tried_agent
= 0;
2687 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
2688 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
2689 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
2690 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
2691 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
2692 s
->publickey_blob
= NULL
;
2694 s
->publickey_blob
= NULL
;
2696 while (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
2697 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2699 if (agent_exists() && !s
->tried_agent
) {
2701 * Attempt RSA authentication using Pageant.
2707 logevent("Pageant is running. Requesting keys.");
2709 /* Request the keys held by the agent. */
2710 PUT_32BIT(s
->request
, 1);
2711 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2712 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
2713 ssh_agent_callback
, ssh
)) {
2717 bombout(("Unexpected data from server while waiting"
2718 " for agent response"));
2721 } while (ispkt
|| inlen
> 0);
2722 r
= ssh
->agent_response
;
2723 s
->responselen
= ssh
->agent_response_len
;
2725 s
->response
= (unsigned char *) r
;
2726 if (s
->response
&& s
->responselen
>= 5 &&
2727 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
2728 s
->p
= s
->response
+ 5;
2729 s
->nkeys
= GET_32BIT(s
->p
);
2733 sprintf(buf
, "Pageant has %d SSH1 keys", s
->nkeys
);
2736 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
2739 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
2742 if (s
->publickey_blob
&&
2743 !memcmp(s
->p
, s
->publickey_blob
,
2744 s
->publickey_bloblen
)) {
2745 logevent("This key matches configured key file");
2746 s
->tried_publickey
= 1;
2751 do { /* do while (0) to make breaking easy */
2752 n
= ssh1_read_bignum
2753 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
2758 n
= ssh1_read_bignum
2759 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
2764 if (s
->responselen
- (s
->p
-s
->response
) < 4)
2766 s
->commentlen
= GET_32BIT(s
->p
);
2768 if (s
->responselen
- (s
->p
-s
->response
) <
2771 s
->commentp
= (char *)s
->p
;
2772 s
->p
+= s
->commentlen
;
2776 logevent("Pageant key list packet was truncated");
2780 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
2781 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
2783 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2784 logevent("Key refused");
2787 logevent("Received RSA challenge");
2788 if ((s
->challenge
= ssh1_pkt_getmp(ssh
)) == NULL
) {
2789 bombout(("Server's RSA challenge was badly formatted"));
2794 char *agentreq
, *q
, *ret
;
2797 len
= 1 + 4; /* message type, bit count */
2798 len
+= ssh1_bignum_length(s
->key
.exponent
);
2799 len
+= ssh1_bignum_length(s
->key
.modulus
);
2800 len
+= ssh1_bignum_length(s
->challenge
);
2801 len
+= 16; /* session id */
2802 len
+= 4; /* response format */
2803 agentreq
= snewn(4 + len
, char);
2804 PUT_32BIT(agentreq
, len
);
2806 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
2807 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
2809 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
2810 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
2811 q
+= ssh1_write_bignum(q
, s
->challenge
);
2812 memcpy(q
, s
->session_id
, 16);
2814 PUT_32BIT(q
, 1); /* response format */
2815 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
2816 ssh_agent_callback
, ssh
)) {
2821 bombout(("Unexpected data from server"
2822 " while waiting for agent"
2826 } while (ispkt
|| inlen
> 0);
2827 vret
= ssh
->agent_response
;
2828 retlen
= ssh
->agent_response_len
;
2833 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
2834 logevent("Sending Pageant's response");
2835 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
2836 PKT_DATA
, ret
+ 5, 16,
2840 if (ssh
->pktin
.type
== SSH1_SMSG_SUCCESS
) {
2842 ("Pageant's response accepted");
2843 if (flags
& FLAG_VERBOSE
) {
2844 c_write_str(ssh
, "Authenticated using"
2846 c_write(ssh
, s
->commentp
,
2848 c_write_str(ssh
, "\" from agent\r\n");
2853 ("Pageant's response not accepted");
2856 ("Pageant failed to answer challenge");
2860 logevent("No reply received from Pageant");
2863 freebn(s
->key
.exponent
);
2864 freebn(s
->key
.modulus
);
2865 freebn(s
->challenge
);
2874 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
2875 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
2877 if (ssh
->cfg
.try_tis_auth
&&
2878 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
2879 !s
->tis_auth_refused
) {
2880 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
2881 logevent("Requested TIS authentication");
2882 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
2884 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
2885 logevent("TIS authentication declined");
2886 if (flags
& FLAG_INTERACTIVE
)
2887 c_write_str(ssh
, "TIS authentication refused.\r\n");
2888 s
->tis_auth_refused
= 1;
2894 ssh_pkt_getstring(ssh
, &challenge
, &challengelen
);
2896 bombout(("TIS challenge packet was badly formed"));
2899 logevent("Received TIS challenge");
2900 if (challengelen
> sizeof(s
->prompt
) - 1)
2901 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
2902 memcpy(s
->prompt
, challenge
, challengelen
);
2903 /* Prompt heuristic comes from OpenSSH */
2904 strncpy(s
->prompt
+ challengelen
,
2905 memchr(s
->prompt
, '\n', challengelen
) ?
2906 "": "\r\nResponse: ",
2907 (sizeof s
->prompt
) - challengelen
);
2908 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
2911 if (ssh
->cfg
.try_tis_auth
&&
2912 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
2913 !s
->ccard_auth_refused
) {
2914 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
2915 logevent("Requested CryptoCard authentication");
2916 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
2918 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
2919 logevent("CryptoCard authentication declined");
2920 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
2921 s
->ccard_auth_refused
= 1;
2927 ssh_pkt_getstring(ssh
, &challenge
, &challengelen
);
2929 bombout(("CryptoCard challenge packet was badly formed"));
2932 logevent("Received CryptoCard challenge");
2933 if (challengelen
> sizeof(s
->prompt
) - 1)
2934 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
2935 memcpy(s
->prompt
, challenge
, challengelen
);
2936 strncpy(s
->prompt
+ challengelen
,
2937 memchr(s
->prompt
, '\n', challengelen
) ?
2938 "" : "\r\nResponse: ",
2939 sizeof(s
->prompt
) - challengelen
);
2940 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
2943 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2944 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
2945 s
->username
, ssh
->savedhost
);
2947 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2948 char *comment
= NULL
;
2951 if (flags
& FLAG_VERBOSE
)
2952 c_write_str(ssh
, "Trying public key authentication.\r\n");
2953 logeventf(ssh
, "Trying public key \"%s\"",
2954 filename_to_str(&ssh
->cfg
.keyfile
));
2955 type
= key_type(&ssh
->cfg
.keyfile
);
2956 if (type
!= SSH_KEYTYPE_SSH1
) {
2957 sprintf(msgbuf
, "Key is of wrong type (%s)",
2958 key_type_to_str(type
));
2960 c_write_str(ssh
, msgbuf
);
2961 c_write_str(ssh
, "\r\n");
2962 s
->tried_publickey
= 1;
2965 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
2966 if (flags
& FLAG_VERBOSE
)
2967 c_write_str(ssh
, "No passphrase required.\r\n");
2970 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
2975 * Show password prompt, having first obtained it via a TIS
2976 * or CryptoCard exchange if we're doing TIS or CryptoCard
2980 if (!ssh_get_line(s
->prompt
, s
->password
,
2981 sizeof(s
->password
), TRUE
)) {
2983 * get_line failed to get a password (for example
2984 * because one was supplied on the command line
2985 * which has already failed to work). Terminate.
2987 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
2988 PKT_STR
, "No more passwords available to try",
2990 logevent("Unable to authenticate");
2991 connection_fatal(ssh
->frontend
, "Unable to authenticate");
2992 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2996 /* Prompt may have come from server. We've munged it a bit, so
2997 * we know it to be zero-terminated at least once. */
2998 int ret
; /* need not be saved over crReturn */
2999 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3002 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3004 crWaitUntil(!ispkt
);
3005 ret
= process_userpass_input(ssh
, in
, inlen
);
3009 c_write_str(ssh
, "\r\n");
3013 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3015 * Try public key authentication with the specified
3018 s
->tried_publickey
= 1;
3021 const char *error
= NULL
;
3022 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3025 c_write_str(ssh
, "Couldn't load private key from ");
3026 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3027 c_write_str(ssh
, " (");
3028 c_write_str(ssh
, error
);
3029 c_write_str(ssh
, ").\r\n");
3030 continue; /* go and try password */
3033 c_write_str(ssh
, "Wrong passphrase.\r\n");
3034 s
->tried_publickey
= 0;
3035 continue; /* try again */
3040 * Send a public key attempt.
3042 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3043 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3046 if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3047 c_write_str(ssh
, "Server refused our public key.\r\n");
3048 continue; /* go and try password */
3050 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3051 bombout(("Bizarre response to offer of public key"));
3057 unsigned char buffer
[32];
3058 Bignum challenge
, response
;
3060 if ((challenge
= ssh1_pkt_getmp(ssh
)) == NULL
) {
3061 bombout(("Server's RSA challenge was badly formatted"));
3064 response
= rsadecrypt(challenge
, &s
->key
);
3065 freebn(s
->key
.private_exponent
);/* burn the evidence */
3067 for (i
= 0; i
< 32; i
++) {
3068 buffer
[i
] = bignum_byte(response
, 31 - i
);
3072 MD5Update(&md5c
, buffer
, 32);
3073 MD5Update(&md5c
, s
->session_id
, 16);
3074 MD5Final(buffer
, &md5c
);
3076 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3077 PKT_DATA
, buffer
, 16, PKT_END
);
3084 if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3085 if (flags
& FLAG_VERBOSE
)
3086 c_write_str(ssh
, "Failed to authenticate with"
3087 " our public key.\r\n");
3088 continue; /* go and try password */
3089 } else if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
) {
3090 bombout(("Bizarre response to RSA authentication response"));
3094 break; /* we're through! */
3096 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3098 * Defence against traffic analysis: we send a
3099 * whole bunch of packets containing strings of
3100 * different lengths. One of these strings is the
3101 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3102 * The others are all random data in
3103 * SSH1_MSG_IGNORE packets. This way a passive
3104 * listener can't tell which is the password, and
3105 * hence can't deduce the password length.
3107 * Anybody with a password length greater than 16
3108 * bytes is going to have enough entropy in their
3109 * password that a listener won't find it _that_
3110 * much help to know how long it is. So what we'll
3113 * - if password length < 16, we send 15 packets
3114 * containing string lengths 1 through 15
3116 * - otherwise, we let N be the nearest multiple
3117 * of 8 below the password length, and send 8
3118 * packets containing string lengths N through
3119 * N+7. This won't obscure the order of
3120 * magnitude of the password length, but it will
3121 * introduce a bit of extra uncertainty.
3123 * A few servers (the old 1.2.18 through 1.2.22)
3124 * can't deal with SSH1_MSG_IGNORE. For these
3125 * servers, we need an alternative defence. We make
3126 * use of the fact that the password is interpreted
3127 * as a C string: so we can append a NUL, then some
3130 * One server (a Cisco one) can deal with neither
3131 * SSH1_MSG_IGNORE _nor_ a padded password string.
3132 * For this server we are left with no defences
3133 * against password length sniffing.
3135 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3137 * The server can deal with SSH1_MSG_IGNORE, so
3138 * we can use the primary defence.
3140 int bottom
, top
, pwlen
, i
;
3143 pwlen
= strlen(s
->password
);
3145 bottom
= 0; /* zero length passwords are OK! :-) */
3148 bottom
= pwlen
& ~7;
3152 assert(pwlen
>= bottom
&& pwlen
<= top
);
3154 randomstr
= snewn(top
+ 1, char);
3156 for (i
= bottom
; i
<= top
; i
++) {
3158 defer_packet(ssh
, s
->pwpkt_type
,
3159 PKT_STR
, s
->password
, PKT_END
);
3161 for (j
= 0; j
< i
; j
++) {
3163 randomstr
[j
] = random_byte();
3164 } while (randomstr
[j
] == '\0');
3166 randomstr
[i
] = '\0';
3167 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3168 PKT_STR
, randomstr
, PKT_END
);
3171 logevent("Sending password with camouflage packets");
3172 ssh_pkt_defersend(ssh
);
3175 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3177 * The server can't deal with SSH1_MSG_IGNORE
3178 * but can deal with padded passwords, so we
3179 * can use the secondary defence.
3185 len
= strlen(s
->password
);
3186 if (len
< sizeof(string
)) {
3188 strcpy(string
, s
->password
);
3189 len
++; /* cover the zero byte */
3190 while (len
< sizeof(string
)) {
3191 string
[len
++] = (char) random_byte();
3196 logevent("Sending length-padded password");
3197 send_packet(ssh
, s
->pwpkt_type
, PKT_INT
, len
,
3198 PKT_DATA
, ss
, len
, PKT_END
);
3201 * The server has _both_
3202 * BUG_CHOKES_ON_SSH1_IGNORE and
3203 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3204 * therefore nothing we can do.
3207 len
= strlen(s
->password
);
3208 logevent("Sending unpadded password");
3209 send_packet(ssh
, s
->pwpkt_type
, PKT_INT
, len
,
3210 PKT_DATA
, s
->password
, len
, PKT_END
);
3213 send_packet(ssh
, s
->pwpkt_type
, PKT_STR
, s
->password
, PKT_END
);
3216 logevent("Sent password");
3217 memset(s
->password
, 0, strlen(s
->password
));
3219 if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3220 if (flags
& FLAG_VERBOSE
)
3221 c_write_str(ssh
, "Access denied\r\n");
3222 logevent("Authentication refused");
3223 } else if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
) {
3224 bombout(("Strange packet received, type %d", ssh
->pktin
.type
));
3229 logevent("Authentication successful");
3234 void sshfwd_close(struct ssh_channel
*c
)
3238 if (ssh
->state
!= SSH_STATE_SESSION
) {
3239 assert(ssh
->state
== SSH_STATE_CLOSED
);
3243 if (c
&& !c
->closes
) {
3245 * If the channel's remoteid is -1, we have sent
3246 * CHANNEL_OPEN for this channel, but it hasn't even been
3247 * acknowledged by the server. So we must set a close flag
3248 * on it now, and then when the server acks the channel
3249 * open, we can close it then.
3251 if (((int)c
->remoteid
) != -1) {
3252 if (ssh
->version
== 1) {
3253 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3256 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_CLOSE
);
3257 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
3261 c
->closes
= 1; /* sent MSG_CLOSE */
3262 if (c
->type
== CHAN_X11
) {
3264 logevent("Forwarded X11 connection terminated");
3265 } else if (c
->type
== CHAN_SOCKDATA
||
3266 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3268 logevent("Forwarded port closed");
3273 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3277 if (ssh
->state
!= SSH_STATE_SESSION
) {
3278 assert(ssh
->state
== SSH_STATE_CLOSED
);
3282 if (ssh
->version
== 1) {
3283 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3284 PKT_INT
, c
->remoteid
,
3285 PKT_INT
, len
, PKT_DATA
, buf
, len
, PKT_END
);
3287 * In SSH1 we can return 0 here - implying that forwarded
3288 * connections are never individually throttled - because
3289 * the only circumstance that can cause throttling will be
3290 * the whole SSH connection backing up, in which case
3291 * _everything_ will be throttled as a whole.
3295 ssh2_add_channel_data(c
, buf
, len
);
3296 return ssh2_try_send(c
);
3300 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3304 if (ssh
->state
!= SSH_STATE_SESSION
) {
3305 assert(ssh
->state
== SSH_STATE_CLOSED
);
3309 if (ssh
->version
== 1) {
3310 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3311 c
->v
.v1
.throttling
= 0;
3312 ssh1_throttle(ssh
, -1);
3315 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3319 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
3321 crBegin(ssh
->ssh1_protocol_crstate
);
3325 while (!do_ssh1_login(ssh
, in
, inlen
, ispkt
)) {
3328 if (ssh
->state
== SSH_STATE_CLOSED
)
3331 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
3332 logevent("Requesting agent forwarding");
3333 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
3337 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3338 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3339 bombout(("Protocol confusion"));
3341 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3342 logevent("Agent forwarding refused");
3344 logevent("Agent forwarding enabled");
3345 ssh
->agentfwd_enabled
= TRUE
;
3349 if (ssh
->cfg
.x11_forward
) {
3350 char proto
[20], data
[64];
3351 logevent("Requesting X11 forwarding");
3352 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
3353 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
3354 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
3355 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
3356 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
3357 PKT_STR
, proto
, PKT_STR
, data
,
3358 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
3361 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
3362 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
3367 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3368 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3369 bombout(("Protocol confusion"));
3371 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3372 logevent("X11 forwarding refused");
3374 logevent("X11 forwarding enabled");
3375 ssh
->X11_fwd_enabled
= TRUE
;
3382 int sport
,dport
,sserv
,dserv
;
3383 char sports
[256], dports
[256], saddr
[256], host
[256];
3385 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3386 /* Add port forwardings. */
3387 ssh
->portfwd_strptr
= ssh
->cfg
.portfwd
;
3388 while (*ssh
->portfwd_strptr
) {
3389 type
= *ssh
->portfwd_strptr
++;
3392 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= '\t') {
3393 if (*ssh
->portfwd_strptr
== ':') {
3395 * We've seen a colon in the middle of the
3396 * source port number. This means that
3397 * everything we've seen until now is the
3398 * source _address_, so we'll move it into
3399 * saddr and start sports from the beginning
3402 ssh
->portfwd_strptr
++;
3404 strcpy(saddr
, sports
);
3407 if (n
< 255) sports
[n
++] = *ssh
->portfwd_strptr
++;
3411 if (*ssh
->portfwd_strptr
== '\t')
3412 ssh
->portfwd_strptr
++;
3414 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= ':') {
3415 if (n
< 255) host
[n
++] = *ssh
->portfwd_strptr
++;
3418 if (*ssh
->portfwd_strptr
== ':')
3419 ssh
->portfwd_strptr
++;
3421 while (*ssh
->portfwd_strptr
) {
3422 if (n
< 255) dports
[n
++] = *ssh
->portfwd_strptr
++;
3425 ssh
->portfwd_strptr
++;
3426 dport
= atoi(dports
);
3430 dport
= net_service_lookup(dports
);
3432 logeventf(ssh
, "Service lookup failed for"
3433 " destination port \"%s\"", dports
);
3437 while (*ssh
->portfwd_strptr
) ssh
->portfwd_strptr
++;
3439 ssh
->portfwd_strptr
++; /* eat the NUL and move to next one */
3441 sport
= atoi(sports
);
3445 sport
= net_service_lookup(sports
);
3447 logeventf(ssh
, "Service lookup failed for source"
3448 " port \"%s\"", sports
);
3451 if (sport
&& dport
) {
3453 pfd_addforward(host
, dport
, *saddr ? saddr
: NULL
,
3454 sport
, ssh
, &ssh
->cfg
);
3455 logeventf(ssh
, "Local port %.*s%.*s%.*s%.*s%d%.*s"
3456 " forwarding to %s:%.*s%.*s%d%.*s",
3457 (int)(*saddr?
strlen(saddr
):0), *saddr?saddr
:NULL
,
3458 (int)(*saddr?
1:0), ":",
3459 (int)(sserv ?
strlen(sports
) : 0), sports
,
3460 sserv
, "(", sport
, sserv
, ")",
3462 (int)(dserv ?
strlen(dports
) : 0), dports
,
3463 dserv
, "(", dport
, dserv
, ")");
3464 } else if (type
== 'D') {
3465 pfd_addforward(NULL
, -1, *saddr ? saddr
: NULL
,
3466 sport
, ssh
, &ssh
->cfg
);
3467 logeventf(ssh
, "Local port %.*s%.*s%.*s%.*s%d%.*s"
3468 " doing SOCKS dynamic forwarding",
3469 (int)(*saddr?
strlen(saddr
):0), *saddr?saddr
:NULL
,
3470 (int)(*saddr?
1:0), ":",
3471 (int)(sserv ?
strlen(sports
) : 0), sports
,
3472 sserv
, "(", sport
, sserv
, ")");
3474 struct ssh_rportfwd
*pf
;
3475 pf
= snew(struct ssh_rportfwd
);
3476 strcpy(pf
->dhost
, host
);
3480 "SSH1 cannot handle source address spec \"%s:%d\"; ignoring",
3483 if (add234(ssh
->rportfwds
, pf
) != pf
) {
3485 "Duplicate remote port forwarding to %s:%d",
3489 logeventf(ssh
, "Requesting remote port %.*s%.*s%d%.*s"
3490 " forward to %s:%.*s%.*s%d%.*s",
3491 (int)(sserv ?
strlen(sports
) : 0), sports
,
3492 sserv
, "(", sport
, sserv
, ")",
3494 (int)(dserv ?
strlen(dports
) : 0), dports
,
3495 dserv
, "(", dport
, dserv
, ")");
3496 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
3504 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3505 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3506 bombout(("Protocol confusion"));
3508 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3509 c_write_str(ssh
, "Server refused port"
3512 logevent("Remote port forwarding enabled");
3519 if (!ssh
->cfg
.nopty
) {
3520 /* Unpick the terminal-speed string. */
3521 /* XXX perhaps we should allow no speeds to be sent. */
3522 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
3523 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
3524 /* Send the pty request. */
3525 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
3526 PKT_STR
, ssh
->cfg
.termtype
,
3527 PKT_INT
, ssh
->term_height
,
3528 PKT_INT
, ssh
->term_width
,
3529 PKT_INT
, 0, PKT_INT
, 0, /* width,height in pixels */
3530 PKT_CHAR
, 192, PKT_INT
, ssh
->ispeed
, /* TTY_OP_ISPEED */
3531 PKT_CHAR
, 193, PKT_INT
, ssh
->ospeed
, /* TTY_OP_OSPEED */
3532 PKT_CHAR
, 0, PKT_END
);
3533 ssh
->state
= SSH_STATE_INTERMED
;
3537 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3538 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3539 bombout(("Protocol confusion"));
3541 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3542 c_write_str(ssh
, "Server refused to allocate pty\r\n");
3543 ssh
->editing
= ssh
->echoing
= 1;
3545 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
3546 ssh
->ospeed
, ssh
->ispeed
);
3548 ssh
->editing
= ssh
->echoing
= 1;
3551 if (ssh
->cfg
.compression
) {
3552 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
3556 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3557 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3558 bombout(("Protocol confusion"));
3560 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3561 c_write_str(ssh
, "Server refused to compress\r\n");
3563 logevent("Started compression");
3564 ssh
->v1_compressing
= TRUE
;
3565 ssh
->cs_comp_ctx
= zlib_compress_init();
3566 logevent("Initialised zlib (RFC1950) compression");
3567 ssh
->sc_comp_ctx
= zlib_decompress_init();
3568 logevent("Initialised zlib (RFC1950) decompression");
3572 * Start the shell or command.
3574 * Special case: if the first-choice command is an SSH2
3575 * subsystem (hence not usable here) and the second choice
3576 * exists, we fall straight back to that.
3579 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
3581 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
3582 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
3583 ssh
->fallback_cmd
= TRUE
;
3586 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
3588 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
3589 logevent("Started session");
3592 ssh
->state
= SSH_STATE_SESSION
;
3593 if (ssh
->size_needed
)
3594 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
3595 if (ssh
->eof_needed
)
3596 ssh_special(ssh
, TS_EOF
);
3599 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
3601 ssh
->channels
= newtree234(ssh_channelcmp
);
3605 if (ssh
->pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
3606 ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
3608 int stringlen
, bufsize
;
3610 ssh_pkt_getstring(ssh
, &string
, &stringlen
);
3611 if (string
== NULL
) {
3612 bombout(("Incoming terminal data packet was badly formed"));
3617 from_backend(ssh
->frontend
,
3618 ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
,
3620 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3621 ssh
->v1_stdout_throttling
= 1;
3622 ssh1_throttle(ssh
, +1);
3624 } else if (ssh
->pktin
.type
== SSH1_MSG_DISCONNECT
) {
3625 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3626 logevent("Received disconnect request");
3628 } else if (ssh
->pktin
.type
== SSH1_SMSG_X11_OPEN
) {
3629 /* Remote side is trying to open a channel to talk to our
3630 * X-Server. Give them back a local channel number. */
3631 struct ssh_channel
*c
;
3632 int remoteid
= ssh_pkt_getuint32(ssh
);
3634 logevent("Received X11 connect request");
3635 /* Refuse if X11 forwarding is disabled. */
3636 if (!ssh
->X11_fwd_enabled
) {
3637 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3638 PKT_INT
, remoteid
, PKT_END
);
3639 logevent("Rejected X11 connect request");
3641 c
= snew(struct ssh_channel
);
3644 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
3645 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
3646 logevent("Opening X11 forward connection failed");
3648 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3649 PKT_INT
, remoteid
, PKT_END
);
3652 ("Opening X11 forward connection succeeded");
3653 c
->remoteid
= remoteid
;
3654 c
->localid
= alloc_channel_id(ssh
);
3656 c
->v
.v1
.throttling
= 0;
3657 c
->type
= CHAN_X11
; /* identify channel type */
3658 add234(ssh
->channels
, c
);
3659 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3660 PKT_INT
, c
->remoteid
, PKT_INT
,
3661 c
->localid
, PKT_END
);
3662 logevent("Opened X11 forward channel");
3665 } else if (ssh
->pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
3666 /* Remote side is trying to open a channel to talk to our
3667 * agent. Give them back a local channel number. */
3668 struct ssh_channel
*c
;
3669 int remoteid
= ssh_pkt_getuint32(ssh
);
3671 /* Refuse if agent forwarding is disabled. */
3672 if (!ssh
->agentfwd_enabled
) {
3673 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3674 PKT_INT
, remoteid
, PKT_END
);
3676 c
= snew(struct ssh_channel
);
3678 c
->remoteid
= remoteid
;
3679 c
->localid
= alloc_channel_id(ssh
);
3681 c
->v
.v1
.throttling
= 0;
3682 c
->type
= CHAN_AGENT
; /* identify channel type */
3683 c
->u
.a
.lensofar
= 0;
3684 add234(ssh
->channels
, c
);
3685 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3686 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
3689 } else if (ssh
->pktin
.type
== SSH1_MSG_PORT_OPEN
) {
3690 /* Remote side is trying to open a channel to talk to a
3691 * forwarded port. Give them back a local channel number. */
3692 struct ssh_channel
*c
;
3693 struct ssh_rportfwd pf
;
3696 char *host
, buf
[1024];
3698 c
= snew(struct ssh_channel
);
3701 remoteid
= ssh_pkt_getuint32(ssh
);
3702 ssh_pkt_getstring(ssh
, &host
, &hostsize
);
3703 port
= ssh_pkt_getuint32(ssh
);
3705 if (hostsize
>= lenof(pf
.dhost
))
3706 hostsize
= lenof(pf
.dhost
)-1;
3707 memcpy(pf
.dhost
, host
, hostsize
);
3708 pf
.dhost
[hostsize
] = '\0';
3711 if (find234(ssh
->rportfwds
, &pf
, NULL
) == NULL
) {
3712 sprintf(buf
, "Rejected remote port open request for %s:%d",
3715 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3716 PKT_INT
, remoteid
, PKT_END
);
3718 sprintf(buf
, "Received remote port open request for %s:%d",
3721 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
3725 sprintf(buf
, "Port open failed: %s", e
);
3728 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3729 PKT_INT
, remoteid
, PKT_END
);
3731 c
->remoteid
= remoteid
;
3732 c
->localid
= alloc_channel_id(ssh
);
3734 c
->v
.v1
.throttling
= 0;
3735 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
3736 add234(ssh
->channels
, c
);
3737 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3738 PKT_INT
, c
->remoteid
, PKT_INT
,
3739 c
->localid
, PKT_END
);
3740 logevent("Forwarded port opened successfully");
3744 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
) {
3745 unsigned int remoteid
= ssh_pkt_getuint32(ssh
);
3746 unsigned int localid
= ssh_pkt_getuint32(ssh
);
3747 struct ssh_channel
*c
;
3749 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
3750 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3751 c
->remoteid
= localid
;
3752 c
->type
= CHAN_SOCKDATA
;
3753 c
->v
.v1
.throttling
= 0;
3754 pfd_confirm(c
->u
.pfd
.s
);
3757 if (c
&& c
->closes
) {
3759 * We have a pending close on this channel,
3760 * which we decided on before the server acked
3761 * the channel open. So now we know the
3762 * remoteid, we can close it again.
3764 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
3765 PKT_INT
, c
->remoteid
, PKT_END
);
3768 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_OPEN_FAILURE
) {
3769 unsigned int remoteid
= ssh_pkt_getuint32(ssh
);
3770 struct ssh_channel
*c
;
3772 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
3773 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3774 logevent("Forwarded connection refused by server");
3775 pfd_close(c
->u
.pfd
.s
);
3776 del234(ssh
->channels
, c
);
3780 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
3781 ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
3782 /* Remote side closes a channel. */
3783 unsigned i
= ssh_pkt_getuint32(ssh
);
3784 struct ssh_channel
*c
;
3785 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
3786 if (c
&& ((int)c
->remoteid
) != -1) {
3789 (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
3791 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
3792 logevent("Forwarded X11 connection terminated");
3793 assert(c
->u
.x11
.s
!= NULL
);
3794 x11_close(c
->u
.x11
.s
);
3797 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
3798 logevent("Forwarded port closed");
3799 assert(c
->u
.pfd
.s
!= NULL
);
3800 pfd_close(c
->u
.pfd
.s
);
3804 c
->closes
|= (closetype
<< 2); /* seen this message */
3805 if (!(c
->closes
& closetype
)) {
3806 send_packet(ssh
, ssh
->pktin
.type
, PKT_INT
, c
->remoteid
,
3808 c
->closes
|= closetype
; /* sent it too */
3811 if (c
->closes
== 15) {
3812 del234(ssh
->channels
, c
);
3816 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
3817 ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
3818 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
3822 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
3823 /* Data sent down one of our channels. */
3824 int i
= ssh_pkt_getuint32(ssh
);
3827 struct ssh_channel
*c
;
3829 ssh_pkt_getstring(ssh
, &p
, &len
);
3831 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
3836 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
3839 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
3842 /* Data for an agent message. Buffer it. */
3844 if (c
->u
.a
.lensofar
< 4) {
3845 int l
= min(4 - c
->u
.a
.lensofar
, len
);
3846 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
3850 c
->u
.a
.lensofar
+= l
;
3852 if (c
->u
.a
.lensofar
== 4) {
3854 4 + GET_32BIT(c
->u
.a
.msglen
);
3855 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
3857 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
3859 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
3861 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
3863 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
3867 c
->u
.a
.lensofar
+= l
;
3869 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
3872 if (agent_query(c
->u
.a
.message
,
3875 ssh_agentf_callback
, c
))
3876 ssh_agentf_callback(c
, reply
, replylen
);
3877 sfree(c
->u
.a
.message
);
3878 c
->u
.a
.lensofar
= 0;
3881 bufsize
= 0; /* agent channels never back up */
3884 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3885 c
->v
.v1
.throttling
= 1;
3886 ssh1_throttle(ssh
, +1);
3889 } else if (ssh
->pktin
.type
== SSH1_SMSG_SUCCESS
) {
3890 /* may be from EXEC_SHELL on some servers */
3891 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3892 /* may be from EXEC_SHELL on some servers
3893 * if no pty is available or in other odd cases. Ignore */
3894 } else if (ssh
->pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
3896 ssh
->exitcode
= ssh_pkt_getuint32(ssh
);
3897 sprintf(buf
, "Server sent command exit status %d",
3900 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
3902 * In case `helpful' firewalls or proxies tack
3903 * extra human-readable text on the end of the
3904 * session which we might mistake for another
3905 * encrypted packet, we close the session once
3906 * we've sent EXIT_CONFIRMATION.
3908 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3911 bombout(("Strange packet received: type %d", ssh
->pktin
.type
));
3916 int len
= min(inlen
, 512);
3917 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
,
3918 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
3929 * Utility routine for decoding comma-separated strings in KEXINIT.
3931 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
3934 if (!needle
|| !haystack
) /* protect against null pointers */
3936 needlen
= strlen(needle
);
3939 * Is it at the start of the string?
3941 if (haylen
>= needlen
&& /* haystack is long enough */
3942 !memcmp(needle
, haystack
, needlen
) && /* initial match */
3943 (haylen
== needlen
|| haystack
[needlen
] == ',')
3944 /* either , or EOS follows */
3948 * If not, search for the next comma and resume after that.
3949 * If no comma found, terminate.
3951 while (haylen
> 0 && *haystack
!= ',')
3952 haylen
--, haystack
++;
3955 haylen
--, haystack
++; /* skip over comma itself */
3960 * SSH2 key creation method.
3962 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
3963 unsigned char *sessid
, char chr
,
3964 unsigned char *keyspace
)
3967 /* First 20 bytes. */
3969 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
3971 SHA_Bytes(&s
, H
, 20);
3972 SHA_Bytes(&s
, &chr
, 1);
3973 SHA_Bytes(&s
, sessid
, 20);
3974 SHA_Final(&s
, keyspace
);
3975 /* Next 20 bytes. */
3977 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
3979 SHA_Bytes(&s
, H
, 20);
3980 SHA_Bytes(&s
, keyspace
, 20);
3981 SHA_Final(&s
, keyspace
+ 20);
3985 * Handle the SSH2 transport layer.
3987 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
3989 struct do_ssh2_transport_state
{
3990 int nbits
, pbits
, warn
;
3991 Bignum p
, g
, e
, f
, K
;
3992 int kex_init_value
, kex_reply_value
;
3993 const struct ssh_mac
**maclist
;
3995 const struct ssh2_cipher
*cscipher_tobe
;
3996 const struct ssh2_cipher
*sccipher_tobe
;
3997 const struct ssh_mac
*csmac_tobe
;
3998 const struct ssh_mac
*scmac_tobe
;
3999 const struct ssh_compress
*cscomp_tobe
;
4000 const struct ssh_compress
*sccomp_tobe
;
4001 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4002 int hostkeylen
, siglen
;
4003 void *hkey
; /* actual host key */
4004 unsigned char exchange_hash
[20];
4005 int n_preferred_ciphers
;
4006 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
4007 const struct ssh_compress
*preferred_comp
;
4010 crState(do_ssh2_transport_state
);
4012 crBegin(ssh
->do_ssh2_transport_crstate
);
4014 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
4015 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
4016 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
4024 * Set up the preferred ciphers. (NULL => warn below here)
4026 s
->n_preferred_ciphers
= 0;
4027 for (i
= 0; i
< CIPHER_MAX
; i
++) {
4028 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
4029 case CIPHER_BLOWFISH
:
4030 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
4033 if (ssh
->cfg
.ssh2_des_cbc
) {
4034 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
4038 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
4041 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
4044 /* Flag for later. Don't bother if it's the last in
4046 if (i
< CIPHER_MAX
- 1) {
4047 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
4055 * Set up preferred compression.
4057 if (ssh
->cfg
.compression
)
4058 s
->preferred_comp
= &ssh_zlib
;
4060 s
->preferred_comp
= &ssh_comp_none
;
4063 * Be prepared to work around the buggy MAC problem.
4065 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
4066 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
4068 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
4072 int i
, j
, cipherstr_started
;
4075 * Construct and send our key exchange packet.
4077 ssh2_pkt_init(ssh
, SSH2_MSG_KEXINIT
);
4078 for (i
= 0; i
< 16; i
++)
4079 ssh2_pkt_addbyte(ssh
, (unsigned char) random_byte());
4080 /* List key exchange algorithms. */
4081 ssh2_pkt_addstring_start(ssh
);
4082 for (i
= 0; i
< lenof(kex_algs
); i
++) {
4083 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
4084 (ssh
->remote_bugs
& BUG_SSH2_DH_GEX
))
4086 ssh2_pkt_addstring_str(ssh
, kex_algs
[i
]->name
);
4087 if (i
< lenof(kex_algs
) - 1)
4088 ssh2_pkt_addstring_str(ssh
, ",");
4090 /* List server host key algorithms. */
4091 ssh2_pkt_addstring_start(ssh
);
4092 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4093 ssh2_pkt_addstring_str(ssh
, hostkey_algs
[i
]->name
);
4094 if (i
< lenof(hostkey_algs
) - 1)
4095 ssh2_pkt_addstring_str(ssh
, ",");
4097 /* List client->server encryption algorithms. */
4098 ssh2_pkt_addstring_start(ssh
);
4099 cipherstr_started
= 0;
4100 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4101 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4102 if (!c
) continue; /* warning flag */
4103 for (j
= 0; j
< c
->nciphers
; j
++) {
4104 if (cipherstr_started
)
4105 ssh2_pkt_addstring_str(ssh
, ",");
4106 ssh2_pkt_addstring_str(ssh
, c
->list
[j
]->name
);
4107 cipherstr_started
= 1;
4110 /* List server->client encryption algorithms. */
4111 ssh2_pkt_addstring_start(ssh
);
4112 cipherstr_started
= 0;
4113 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4114 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4115 if (!c
) continue; /* warning flag */
4116 for (j
= 0; j
< c
->nciphers
; j
++) {
4117 if (cipherstr_started
)
4118 ssh2_pkt_addstring_str(ssh
, ",");
4119 ssh2_pkt_addstring_str(ssh
, c
->list
[j
]->name
);
4120 cipherstr_started
= 1;
4123 /* List client->server MAC algorithms. */
4124 ssh2_pkt_addstring_start(ssh
);
4125 for (i
= 0; i
< s
->nmacs
; i
++) {
4126 ssh2_pkt_addstring_str(ssh
, s
->maclist
[i
]->name
);
4127 if (i
< s
->nmacs
- 1)
4128 ssh2_pkt_addstring_str(ssh
, ",");
4130 /* List server->client MAC algorithms. */
4131 ssh2_pkt_addstring_start(ssh
);
4132 for (i
= 0; i
< s
->nmacs
; i
++) {
4133 ssh2_pkt_addstring_str(ssh
, s
->maclist
[i
]->name
);
4134 if (i
< s
->nmacs
- 1)
4135 ssh2_pkt_addstring_str(ssh
, ",");
4137 /* List client->server compression algorithms. */
4138 ssh2_pkt_addstring_start(ssh
);
4139 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4140 const struct ssh_compress
*c
=
4141 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4142 ssh2_pkt_addstring_str(ssh
, c
->name
);
4143 if (i
< lenof(compressions
))
4144 ssh2_pkt_addstring_str(ssh
, ",");
4146 /* List server->client compression algorithms. */
4147 ssh2_pkt_addstring_start(ssh
);
4148 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4149 const struct ssh_compress
*c
=
4150 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4151 ssh2_pkt_addstring_str(ssh
, c
->name
);
4152 if (i
< lenof(compressions
))
4153 ssh2_pkt_addstring_str(ssh
, ",");
4155 /* List client->server languages. Empty list. */
4156 ssh2_pkt_addstring_start(ssh
);
4157 /* List server->client languages. Empty list. */
4158 ssh2_pkt_addstring_start(ssh
);
4159 /* First KEX packet does _not_ follow, because we're not that brave. */
4160 ssh2_pkt_addbool(ssh
, FALSE
);
4162 ssh2_pkt_adduint32(ssh
, 0);
4165 ssh
->exhash
= ssh
->exhashbase
;
4166 sha_string(&ssh
->exhash
, ssh
->pktout
.data
+ 5, ssh
->pktout
.length
- 5);
4172 if (ssh
->pktin
.length
> 5)
4173 sha_string(&ssh
->exhash
, ssh
->pktin
.data
+ 5, ssh
->pktin
.length
- 5);
4176 * Now examine the other side's KEXINIT to see what we're up
4183 if (ssh
->pktin
.type
!= SSH2_MSG_KEXINIT
) {
4184 bombout(("expected key exchange packet from server"));
4188 ssh
->hostkey
= NULL
;
4189 s
->cscipher_tobe
= NULL
;
4190 s
->sccipher_tobe
= NULL
;
4191 s
->csmac_tobe
= NULL
;
4192 s
->scmac_tobe
= NULL
;
4193 s
->cscomp_tobe
= NULL
;
4194 s
->sccomp_tobe
= NULL
;
4195 ssh
->pktin
.savedpos
+= 16; /* skip garbage cookie */
4196 ssh_pkt_getstring(ssh
, &str
, &len
); /* key exchange algorithms */
4197 for (i
= 0; i
< lenof(kex_algs
); i
++) {
4198 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
4199 (ssh
->remote_bugs
& BUG_SSH2_DH_GEX
))
4201 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
4202 ssh
->kex
= kex_algs
[i
];
4206 ssh_pkt_getstring(ssh
, &str
, &len
); /* host key algorithms */
4207 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4208 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
4209 ssh
->hostkey
= hostkey_algs
[i
];
4213 ssh_pkt_getstring(ssh
, &str
, &len
); /* client->server cipher */
4215 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4216 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4220 for (j
= 0; j
< c
->nciphers
; j
++) {
4221 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4222 s
->cscipher_tobe
= c
->list
[j
];
4227 if (s
->cscipher_tobe
) {
4229 askcipher(ssh
->frontend
, s
->cscipher_tobe
->name
, 1);
4233 if (!s
->cscipher_tobe
) {
4234 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
4235 str ? str
: "(null)"));
4239 ssh_pkt_getstring(ssh
, &str
, &len
); /* server->client cipher */
4241 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4242 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4246 for (j
= 0; j
< c
->nciphers
; j
++) {
4247 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4248 s
->sccipher_tobe
= c
->list
[j
];
4253 if (s
->sccipher_tobe
) {
4255 askcipher(ssh
->frontend
, s
->sccipher_tobe
->name
, 2);
4259 if (!s
->sccipher_tobe
) {
4260 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
4261 str ? str
: "(null)"));
4265 ssh_pkt_getstring(ssh
, &str
, &len
); /* client->server mac */
4266 for (i
= 0; i
< s
->nmacs
; i
++) {
4267 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4268 s
->csmac_tobe
= s
->maclist
[i
];
4272 ssh_pkt_getstring(ssh
, &str
, &len
); /* server->client mac */
4273 for (i
= 0; i
< s
->nmacs
; i
++) {
4274 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4275 s
->scmac_tobe
= s
->maclist
[i
];
4279 ssh_pkt_getstring(ssh
, &str
, &len
); /* client->server compression */
4280 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4281 const struct ssh_compress
*c
=
4282 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4283 if (in_commasep_string(c
->name
, str
, len
)) {
4288 ssh_pkt_getstring(ssh
, &str
, &len
); /* server->client compression */
4289 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4290 const struct ssh_compress
*c
=
4291 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4292 if (in_commasep_string(c
->name
, str
, len
)) {
4300 * Work out the number of bits of key we will need from the key
4301 * exchange. We start with the maximum key length of either
4307 csbits
= s
->cscipher_tobe
->keylen
;
4308 scbits
= s
->sccipher_tobe
->keylen
;
4309 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
4311 /* The keys only have 160-bit entropy, since they're based on
4312 * a SHA-1 hash. So cap the key size at 160 bits. */
4317 * If we're doing Diffie-Hellman group exchange, start by
4318 * requesting a group.
4320 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4321 logevent("Doing Diffie-Hellman group exchange");
4322 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
4324 * Work out how big a DH group we will need to allow that
4327 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
4328 ssh2_pkt_init(ssh
, SSH2_MSG_KEX_DH_GEX_REQUEST
);
4329 ssh2_pkt_adduint32(ssh
, s
->pbits
);
4333 if (ssh
->pktin
.type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
4334 bombout(("expected key exchange group packet from server"));
4337 s
->p
= ssh2_pkt_getmp(ssh
);
4338 s
->g
= ssh2_pkt_getmp(ssh
);
4339 ssh
->kex_ctx
= dh_setup_group(s
->p
, s
->g
);
4340 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
4341 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
4343 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP1
;
4344 ssh
->kex_ctx
= dh_setup_group1();
4345 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
4346 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
4349 logevent("Doing Diffie-Hellman key exchange");
4351 * Now generate and send e for Diffie-Hellman.
4353 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
4354 ssh2_pkt_init(ssh
, s
->kex_init_value
);
4355 ssh2_pkt_addmp(ssh
, s
->e
);
4359 if (ssh
->pktin
.type
!= s
->kex_reply_value
) {
4360 bombout(("expected key exchange reply packet from server"));
4363 ssh_pkt_getstring(ssh
, &s
->hostkeydata
, &s
->hostkeylen
);
4364 s
->f
= ssh2_pkt_getmp(ssh
);
4365 ssh_pkt_getstring(ssh
, &s
->sigdata
, &s
->siglen
);
4367 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
4369 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
4370 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4371 sha_uint32(&ssh
->exhash
, s
->pbits
);
4372 sha_mpint(&ssh
->exhash
, s
->p
);
4373 sha_mpint(&ssh
->exhash
, s
->g
);
4375 sha_mpint(&ssh
->exhash
, s
->e
);
4376 sha_mpint(&ssh
->exhash
, s
->f
);
4377 sha_mpint(&ssh
->exhash
, s
->K
);
4378 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
4380 dh_cleanup(ssh
->kex_ctx
);
4381 ssh
->kex_ctx
= NULL
;
4384 debug(("Exchange hash is:\n"));
4385 dmemdump(s
->exchange_hash
, 20);
4388 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
4390 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
4391 (char *)s
->exchange_hash
, 20)) {
4392 bombout(("Server's host key did not match the signature supplied"));
4397 * Authenticate remote host: verify host key. (We've already
4398 * checked the signature of the exchange hash.)
4400 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
4401 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
4402 verify_ssh_host_key(ssh
->frontend
,
4403 ssh
->savedhost
, ssh
->savedport
, ssh
->hostkey
->keytype
,
4404 s
->keystr
, s
->fingerprint
);
4405 if (s
->first_kex
) { /* don't bother logging this in rekeys */
4406 logevent("Host key fingerprint is:");
4407 logevent(s
->fingerprint
);
4409 sfree(s
->fingerprint
);
4411 ssh
->hostkey
->freekey(s
->hkey
);
4414 * Send SSH2_MSG_NEWKEYS.
4416 ssh2_pkt_init(ssh
, SSH2_MSG_NEWKEYS
);
4420 * Expect SSH2_MSG_NEWKEYS from server.
4423 if (ssh
->pktin
.type
!= SSH2_MSG_NEWKEYS
) {
4424 bombout(("expected new-keys packet from server"));
4429 * Create and initialise session keys.
4431 if (ssh
->cs_cipher_ctx
)
4432 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
4433 ssh
->cscipher
= s
->cscipher_tobe
;
4434 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
4436 if (ssh
->sc_cipher_ctx
)
4437 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
4438 ssh
->sccipher
= s
->sccipher_tobe
;
4439 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
4441 if (ssh
->cs_mac_ctx
)
4442 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
4443 ssh
->csmac
= s
->csmac_tobe
;
4444 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
4446 if (ssh
->sc_mac_ctx
)
4447 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
4448 ssh
->scmac
= s
->scmac_tobe
;
4449 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
4451 if (ssh
->cs_comp_ctx
)
4452 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
4453 ssh
->cscomp
= s
->cscomp_tobe
;
4454 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
4456 if (ssh
->sc_comp_ctx
)
4457 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
4458 ssh
->sccomp
= s
->sccomp_tobe
;
4459 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
4462 * Set IVs after keys. Here we use the exchange hash from the
4463 * _first_ key exchange.
4466 unsigned char keyspace
[40];
4468 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
4469 sizeof(s
->exchange_hash
));
4470 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
4471 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
4472 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
4473 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
4474 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
4475 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
4476 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
4477 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
4478 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
4479 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
4480 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
4481 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
4483 logeventf(ssh
, "Initialised %.200s client->server encryption",
4484 ssh
->cscipher
->text_name
);
4485 logeventf(ssh
, "Initialised %.200s server->client encryption",
4486 ssh
->sccipher
->text_name
);
4487 if (ssh
->cscomp
->text_name
)
4488 logeventf(ssh
, "Initialised %s compression",
4489 ssh
->cscomp
->text_name
);
4490 if (ssh
->sccomp
->text_name
)
4491 logeventf(ssh
, "Initialised %s decompression",
4492 ssh
->sccomp
->text_name
);
4495 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4501 * If this is the first key exchange phase, we must pass the
4502 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
4503 * wants to see it but because it will need time to initialise
4504 * itself before it sees an actual packet. In subsequent key
4505 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
4506 * it would only confuse the layer above.
4508 if (!s
->first_kex
) {
4514 * Now we're encrypting. Begin returning 1 to the protocol main
4515 * function so that other things can run on top of the
4516 * transport. If we ever see a KEXINIT, we must go back to the
4519 while (!(ispkt
&& ssh
->pktin
.type
== SSH2_MSG_KEXINIT
)) {
4522 logevent("Server initiated key re-exchange");
4523 goto begin_key_exchange
;
4529 * Add data to an SSH2 channel output buffer.
4531 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
4534 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
4538 * Attempt to send data on an SSH2 channel.
4540 static int ssh2_try_send(struct ssh_channel
*c
)
4544 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
4547 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
4548 if ((unsigned)len
> c
->v
.v2
.remwindow
)
4549 len
= c
->v
.v2
.remwindow
;
4550 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
4551 len
= c
->v
.v2
.remmaxpkt
;
4552 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_DATA
);
4553 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
4554 ssh2_pkt_addstring_start(ssh
);
4555 ssh2_pkt_addstring_data(ssh
, data
, len
);
4557 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
4558 c
->v
.v2
.remwindow
-= len
;
4562 * After having sent as much data as we can, return the amount
4565 return bufchain_size(&c
->v
.v2
.outbuffer
);
4569 * Potentially enlarge the window on an SSH2 channel.
4571 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
4576 * Never send WINDOW_ADJUST for a channel that the remote side
4577 * already thinks it's closed; there's no point, since it won't
4578 * be sending any more data anyway.
4583 if (newwin
> c
->v
.v2
.locwindow
) {
4584 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4585 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
4586 ssh2_pkt_adduint32(ssh
, newwin
- c
->v
.v2
.locwindow
);
4588 c
->v
.v2
.locwindow
= newwin
;
4593 * Handle the SSH2 userauth and connection layers.
4595 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
4597 struct do_ssh2_authconn_state
{
4599 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
4601 AUTH_KEYBOARD_INTERACTIVE
4605 AUTH_TYPE_PUBLICKEY
,
4606 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
4607 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
4609 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
4610 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4612 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
4613 int tried_pubkey_config
, tried_agent
, tried_keyb_inter
;
4614 int kbd_inter_running
;
4616 int num_prompts
, curr_prompt
, echo
;
4621 void *publickey_blob
;
4622 int publickey_bloblen
;
4623 unsigned char request
[5], *response
, *p
;
4627 char *pkblob
, *alg
, *commentp
;
4628 int pklen
, alglen
, commentlen
;
4629 int siglen
, retlen
, len
;
4630 char *q
, *agentreq
, *ret
;
4633 crState(do_ssh2_authconn_state
);
4635 crBegin(ssh
->do_ssh2_authconn_crstate
);
4638 * Request userauth protocol, and await a response to it.
4640 ssh2_pkt_init(ssh
, SSH2_MSG_SERVICE_REQUEST
);
4641 ssh2_pkt_addstring(ssh
, "ssh-userauth");
4643 crWaitUntilV(ispkt
);
4644 if (ssh
->pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
4645 bombout(("Server refused user authentication protocol"));
4650 * We repeat this whole loop, including the username prompt,
4651 * until we manage a successful authentication. If the user
4652 * types the wrong _password_, they can be sent back to the
4653 * beginning to try another username, if this is configured on.
4654 * (If they specify a username in the config, they are never
4655 * asked, even if they do give a wrong password.)
4657 * I think this best serves the needs of
4659 * - the people who have no configuration, no keys, and just
4660 * want to try repeated (username,password) pairs until they
4661 * type both correctly
4663 * - people who have keys and configuration but occasionally
4664 * need to fall back to passwords
4666 * - people with a key held in Pageant, who might not have
4667 * logged in to a particular machine before; so they want to
4668 * type a username, and then _either_ their key will be
4669 * accepted, _or_ they will type a password. If they mistype
4670 * the username they will want to be able to get back and
4673 s
->username
[0] = '\0';
4674 s
->got_username
= FALSE
;
4679 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
4681 * We got a username last time round this loop, and
4682 * with change_username turned off we don't try to get
4685 } else if ((flags
& FLAG_INTERACTIVE
) && !*ssh
->cfg
.username
) {
4686 if (ssh_get_line
&& !ssh_getline_pw_only
) {
4687 if (!ssh_get_line("login as: ",
4688 s
->username
, sizeof(s
->username
), FALSE
)) {
4690 * get_line failed to get a username.
4693 logevent("No username provided. Abandoning session.");
4694 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4698 int ret
; /* need not be saved across crReturn */
4699 c_write_str(ssh
, "login as: ");
4701 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
4703 crWaitUntilV(!ispkt
);
4704 ret
= process_userpass_input(ssh
, in
, inlen
);
4708 c_write_str(ssh
, "\r\n");
4710 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
4713 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
4714 s
->username
[sizeof(s
->username
)-1] = '\0';
4715 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
4716 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
4717 c_write_str(ssh
, stuff
);
4721 s
->got_username
= TRUE
;
4724 * Send an authentication request using method "none": (a)
4725 * just in case it succeeds, and (b) so that we know what
4726 * authentication methods we can usefully try next.
4728 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4730 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4731 ssh2_pkt_addstring(ssh
, s
->username
);
4732 ssh2_pkt_addstring(ssh
, "ssh-connection");/* service requested */
4733 ssh2_pkt_addstring(ssh
, "none"); /* method */
4735 s
->type
= AUTH_TYPE_NONE
;
4737 s
->we_are_in
= FALSE
;
4739 s
->tried_pubkey_config
= FALSE
;
4740 s
->tried_agent
= FALSE
;
4741 s
->tried_keyb_inter
= FALSE
;
4742 s
->kbd_inter_running
= FALSE
;
4743 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
4744 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
4746 logeventf(ssh
, "Reading private key file \"%.150s\"",
4747 filename_to_str(&ssh
->cfg
.keyfile
));
4748 keytype
= key_type(&ssh
->cfg
.keyfile
);
4749 if (keytype
== SSH_KEYTYPE_SSH2
) {
4751 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
4752 &s
->publickey_bloblen
, NULL
);
4755 logeventf(ssh
, "Unable to use this key file (%s)",
4756 key_type_to_str(keytype
));
4757 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
4759 filename_to_str(&ssh
->cfg
.keyfile
),
4760 key_type_to_str(keytype
));
4761 c_write_str(ssh
, msgbuf
);
4763 s
->publickey_blob
= NULL
;
4766 s
->publickey_blob
= NULL
;
4770 * Wait for the result of the last authentication request.
4773 crWaitUntilV(ispkt
);
4774 while (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_BANNER
) {
4778 * Don't show the banner if we're operating in
4779 * non-verbose non-interactive mode. (It's probably
4780 * a script, which means nobody will read the
4781 * banner _anyway_, and moreover the printing of
4782 * the banner will screw up processing on the
4783 * output of (say) plink.)
4785 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
4786 ssh_pkt_getstring(ssh
, &banner
, &size
);
4788 c_write_untrusted(ssh
, banner
, size
);
4790 crWaitUntilV(ispkt
);
4792 if (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_SUCCESS
) {
4793 logevent("Access granted");
4794 s
->we_are_in
= TRUE
;
4798 if (s
->kbd_inter_running
&&
4799 ssh
->pktin
.type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4801 * This is either a further set-of-prompts packet
4802 * in keyboard-interactive authentication, or it's
4803 * the same one and we came back here with `gotit'
4804 * set. In the former case, we must reset the
4805 * curr_prompt variable.
4809 } else if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_FAILURE
) {
4810 bombout(("Strange packet received during authentication: type %d",
4818 * OK, we're now sitting on a USERAUTH_FAILURE message, so
4819 * we can look at the string in it and know what we can
4820 * helpfully try next.
4822 if (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
) {
4825 ssh_pkt_getstring(ssh
, &methods
, &methlen
);
4826 s
->kbd_inter_running
= FALSE
;
4827 if (!ssh2_pkt_getbool(ssh
)) {
4829 * We have received an unequivocal Access
4830 * Denied. This can translate to a variety of
4833 * - if we'd just tried "none" authentication,
4834 * it's not worth printing anything at all
4836 * - if we'd just tried a public key _offer_,
4837 * the message should be "Server refused our
4838 * key" (or no message at all if the key
4839 * came from Pageant)
4841 * - if we'd just tried anything else, the
4842 * message really should be "Access denied".
4844 * Additionally, if we'd just tried password
4845 * authentication, we should break out of this
4846 * whole loop so as to go back to the username
4849 if (s
->type
== AUTH_TYPE_NONE
) {
4851 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
4852 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
4853 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
4854 c_write_str(ssh
, "Server refused our key\r\n");
4855 logevent("Server refused public key");
4856 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
4857 /* server declined keyboard-interactive; ignore */
4859 c_write_str(ssh
, "Access denied\r\n");
4860 logevent("Access denied");
4861 if (s
->type
== AUTH_TYPE_PASSWORD
) {
4862 s
->we_are_in
= FALSE
;
4867 c_write_str(ssh
, "Further authentication required\r\n");
4868 logevent("Further authentication required");
4872 in_commasep_string("publickey", methods
, methlen
);
4874 in_commasep_string("password", methods
, methlen
);
4875 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
4876 in_commasep_string("keyboard-interactive", methods
, methlen
);
4880 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4884 * Most password/passphrase prompts will be
4885 * non-echoing, so we set this to 0 by default.
4886 * Exception is that some keyboard-interactive prompts
4887 * can be echoing, in which case we'll set this to 1.
4891 if (!s
->method
&& s
->can_pubkey
&&
4892 agent_exists() && !s
->tried_agent
) {
4894 * Attempt public-key authentication using Pageant.
4899 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4900 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4902 s
->tried_agent
= TRUE
;
4904 logevent("Pageant is running. Requesting keys.");
4906 /* Request the keys held by the agent. */
4907 PUT_32BIT(s
->request
, 1);
4908 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
4909 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
4910 ssh_agent_callback
, ssh
)) {
4914 bombout(("Unexpected data from server while"
4915 " waiting for agent response"));
4918 } while (ispkt
|| inlen
> 0);
4919 r
= ssh
->agent_response
;
4920 s
->responselen
= ssh
->agent_response_len
;
4922 s
->response
= (unsigned char *) r
;
4923 if (s
->response
&& s
->responselen
>= 5 &&
4924 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
4925 s
->p
= s
->response
+ 5;
4926 s
->nkeys
= GET_32BIT(s
->p
);
4930 sprintf(buf
, "Pageant has %d SSH2 keys", s
->nkeys
);
4933 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
4938 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
4941 s
->pklen
= GET_32BIT(s
->p
);
4943 if (s
->publickey_blob
&&
4944 s
->pklen
== s
->publickey_bloblen
&&
4945 !memcmp(s
->p
, s
->publickey_blob
,
4946 s
->publickey_bloblen
)) {
4947 logevent("This key matches configured key file");
4948 s
->tried_pubkey_config
= 1;
4950 s
->pkblob
= (char *)s
->p
;
4952 s
->alglen
= GET_32BIT(s
->pkblob
);
4953 s
->alg
= s
->pkblob
+ 4;
4954 s
->commentlen
= GET_32BIT(s
->p
);
4956 s
->commentp
= (char *)s
->p
;
4957 s
->p
+= s
->commentlen
;
4958 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4959 ssh2_pkt_addstring(ssh
, s
->username
);
4960 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4961 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
4962 ssh2_pkt_addbool(ssh
, FALSE
); /* no signature included */
4963 ssh2_pkt_addstring_start(ssh
);
4964 ssh2_pkt_addstring_data(ssh
, s
->alg
, s
->alglen
);
4965 ssh2_pkt_addstring_start(ssh
);
4966 ssh2_pkt_addstring_data(ssh
, s
->pkblob
, s
->pklen
);
4969 crWaitUntilV(ispkt
);
4970 if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4971 logevent("Key refused");
4975 if (flags
& FLAG_VERBOSE
) {
4976 c_write_str(ssh
, "Authenticating with "
4978 c_write(ssh
, s
->commentp
, s
->commentlen
);
4979 c_write_str(ssh
, "\" from agent\r\n");
4983 * Server is willing to accept the key.
4984 * Construct a SIGN_REQUEST.
4986 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4987 ssh2_pkt_addstring(ssh
, s
->username
);
4988 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4989 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
4990 ssh2_pkt_addbool(ssh
, TRUE
);
4991 ssh2_pkt_addstring_start(ssh
);
4992 ssh2_pkt_addstring_data(ssh
, s
->alg
, s
->alglen
);
4993 ssh2_pkt_addstring_start(ssh
);
4994 ssh2_pkt_addstring_data(ssh
, s
->pkblob
, s
->pklen
);
4996 s
->siglen
= ssh
->pktout
.length
- 5 + 4 + 20;
4997 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
4999 s
->len
= 1; /* message type */
5000 s
->len
+= 4 + s
->pklen
; /* key blob */
5001 s
->len
+= 4 + s
->siglen
; /* data to sign */
5002 s
->len
+= 4; /* flags */
5003 s
->agentreq
= snewn(4 + s
->len
, char);
5004 PUT_32BIT(s
->agentreq
, s
->len
);
5005 s
->q
= s
->agentreq
+ 4;
5006 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
5007 PUT_32BIT(s
->q
, s
->pklen
);
5009 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
5011 PUT_32BIT(s
->q
, s
->siglen
);
5013 /* Now the data to be signed... */
5014 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
5015 PUT_32BIT(s
->q
, 20);
5018 memcpy(s
->q
, ssh
->v2_session_id
, 20);
5020 memcpy(s
->q
, ssh
->pktout
.data
+ 5,
5021 ssh
->pktout
.length
- 5);
5022 s
->q
+= ssh
->pktout
.length
- 5;
5023 /* And finally the (zero) flags word. */
5025 if (!agent_query(s
->agentreq
, s
->len
+ 4,
5027 ssh_agent_callback
, ssh
)) {
5031 bombout(("Unexpected data from server"
5032 " while waiting for agent"
5036 } while (ispkt
|| inlen
> 0);
5037 vret
= ssh
->agent_response
;
5038 s
->retlen
= ssh
->agent_response_len
;
5043 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
5044 logevent("Sending Pageant's response");
5045 ssh2_add_sigblob(ssh
, s
->pkblob
, s
->pklen
,
5047 GET_32BIT(s
->ret
+ 5));
5053 ("Pageant failed to answer challenge");
5064 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
5065 && !s
->tried_pubkey_config
) {
5066 unsigned char *pub_blob
;
5067 char *algorithm
, *comment
;
5070 s
->tried_pubkey_config
= TRUE
;
5072 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5073 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
5076 * Try the public key supplied in the configuration.
5078 * First, offer the public blob to see if the server is
5079 * willing to accept it.
5082 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
5087 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
5088 ssh2_pkt_addstring(ssh
, s
->username
);
5089 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
5090 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
5091 ssh2_pkt_addbool(ssh
, FALSE
); /* no signature included */
5092 ssh2_pkt_addstring(ssh
, algorithm
);
5093 ssh2_pkt_addstring_start(ssh
);
5094 ssh2_pkt_addstring_data(ssh
, (char *)pub_blob
,
5097 logevent("Offered public key"); /* FIXME */
5099 crWaitUntilV(ispkt
);
5100 if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
5102 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
5103 continue; /* key refused; give up on it */
5106 logevent("Offer of public key accepted");
5108 * Actually attempt a serious authentication using
5111 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
5112 sprintf(s
->pwprompt
,
5113 "Passphrase for key \"%.100s\": ",
5119 if (flags
& FLAG_VERBOSE
) {
5120 c_write_str(ssh
, "Authenticating with public key \"");
5121 c_write_str(ssh
, comment
);
5122 c_write_str(ssh
, "\"\r\n");
5124 s
->method
= AUTH_PUBLICKEY_FILE
;
5128 if (!s
->method
&& s
->can_keyb_inter
&& !s
->tried_keyb_inter
) {
5129 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
5130 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
5131 s
->tried_keyb_inter
= TRUE
;
5133 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5134 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
5136 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
5137 ssh2_pkt_addstring(ssh
, s
->username
);
5138 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
5139 ssh2_pkt_addstring(ssh
, "keyboard-interactive"); /* method */
5140 ssh2_pkt_addstring(ssh
, ""); /* lang */
5141 ssh2_pkt_addstring(ssh
, "");
5144 crWaitUntilV(ispkt
);
5145 if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
5146 if (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
)
5148 logevent("Keyboard-interactive authentication refused");
5149 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
5153 s
->kbd_inter_running
= TRUE
;
5157 if (s
->kbd_inter_running
) {
5158 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
5159 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
5160 s
->tried_keyb_inter
= TRUE
;
5162 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5163 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
5165 if (s
->curr_prompt
== 0) {
5167 * We've got a fresh USERAUTH_INFO_REQUEST.
5168 * Display header data, and start going through
5171 char *name
, *inst
, *lang
;
5172 int name_len
, inst_len
, lang_len
;
5174 ssh_pkt_getstring(ssh
, &name
, &name_len
);
5175 ssh_pkt_getstring(ssh
, &inst
, &inst_len
);
5176 ssh_pkt_getstring(ssh
, &lang
, &lang_len
);
5178 c_write_untrusted(ssh
, name
, name_len
);
5179 c_write_str(ssh
, "\r\n");
5182 c_write_untrusted(ssh
, inst
, inst_len
);
5183 c_write_str(ssh
, "\r\n");
5185 s
->num_prompts
= ssh_pkt_getuint32(ssh
);
5189 * If there are prompts remaining in the packet,
5190 * display one and get a response.
5192 if (s
->curr_prompt
< s
->num_prompts
) {
5196 ssh_pkt_getstring(ssh
, &prompt
, &prompt_len
);
5197 if (prompt_len
> 0) {
5198 static const char trunc
[] = "<prompt truncated>: ";
5199 static const int prlen
= sizeof(s
->pwprompt
) -
5201 if (prompt_len
> prlen
) {
5202 memcpy(s
->pwprompt
, prompt
, prlen
);
5203 strcpy(s
->pwprompt
+ prlen
, trunc
);
5205 memcpy(s
->pwprompt
, prompt
, prompt_len
);
5206 s
->pwprompt
[prompt_len
] = '\0';
5210 "<server failed to send prompt>: ");
5212 s
->echo
= ssh2_pkt_getbool(ssh
);
5218 if (!s
->method
&& s
->can_passwd
) {
5219 s
->method
= AUTH_PASSWORD
;
5220 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5221 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
5222 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
5229 if (!ssh_get_line(s
->pwprompt
, s
->password
,
5230 sizeof(s
->password
), TRUE
)) {
5232 * get_line failed to get a password (for
5233 * example because one was supplied on the
5234 * command line which has already failed to
5237 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
5238 ssh2_pkt_adduint32(ssh
,SSH2_DISCONNECT_BY_APPLICATION
);
5239 ssh2_pkt_addstring(ssh
, "No more passwords available"
5241 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
5243 logevent("Unable to authenticate");
5244 connection_fatal(ssh
->frontend
,
5245 "Unable to authenticate");
5246 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5250 int ret
; /* need not be saved across crReturn */
5251 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
5254 setup_userpass_input(ssh
, s
->password
,
5255 sizeof(s
->password
), s
->echo
);
5257 crWaitUntilV(!ispkt
);
5258 ret
= process_userpass_input(ssh
, in
, inlen
);
5262 c_write_str(ssh
, "\r\n");
5266 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
5268 * We have our passphrase. Now try the actual authentication.
5270 struct ssh2_userkey
*key
;
5271 const char *error
= NULL
;
5273 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
,
5275 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
5276 if (key
== SSH2_WRONG_PASSPHRASE
) {
5277 c_write_str(ssh
, "Wrong passphrase\r\n");
5278 s
->tried_pubkey_config
= FALSE
;
5280 c_write_str(ssh
, "Unable to load private key (");
5281 c_write_str(ssh
, error
);
5282 c_write_str(ssh
, ")\r\n");
5283 s
->tried_pubkey_config
= TRUE
;
5285 /* Send a spurious AUTH_NONE to return to the top. */
5286 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
5287 ssh2_pkt_addstring(ssh
, s
->username
);
5288 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
5289 ssh2_pkt_addstring(ssh
, "none"); /* method */
5291 s
->type
= AUTH_TYPE_NONE
;
5293 unsigned char *pkblob
, *sigblob
, *sigdata
;
5294 int pkblob_len
, sigblob_len
, sigdata_len
;
5298 * We have loaded the private key and the server
5299 * has announced that it's willing to accept it.
5300 * Hallelujah. Generate a signature and send it.
5302 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
5303 ssh2_pkt_addstring(ssh
, s
->username
);
5304 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
5305 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
5306 ssh2_pkt_addbool(ssh
, TRUE
);
5307 ssh2_pkt_addstring(ssh
, key
->alg
->name
);
5308 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
5309 ssh2_pkt_addstring_start(ssh
);
5310 ssh2_pkt_addstring_data(ssh
, (char *)pkblob
, pkblob_len
);
5313 * The data to be signed is:
5317 * followed by everything so far placed in the
5320 sigdata_len
= ssh
->pktout
.length
- 5 + 4 + 20;
5321 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
5323 sigdata
= snewn(sigdata_len
, unsigned char);
5325 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
5326 PUT_32BIT(sigdata
+p
, 20);
5329 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
5330 memcpy(sigdata
+p
, ssh
->pktout
.data
+ 5,
5331 ssh
->pktout
.length
- 5);
5332 p
+= ssh
->pktout
.length
- 5;
5333 assert(p
== sigdata_len
);
5334 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
5335 sigdata_len
, &sigblob_len
);
5336 ssh2_add_sigblob(ssh
, pkblob
, pkblob_len
,
5337 sigblob
, sigblob_len
);
5343 s
->type
= AUTH_TYPE_PUBLICKEY
;
5344 key
->alg
->freekey(key
->data
);
5346 } else if (s
->method
== AUTH_PASSWORD
) {
5348 * We send the password packet lumped tightly together with
5349 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
5350 * string long enough to make the total length of the two
5351 * packets constant. This should ensure that a passive
5352 * listener doing traffic analyis can't work out the length
5355 * For this to work, we need an assumption about the
5356 * maximum length of the password packet. I think 256 is
5357 * pretty conservative. Anyone using a password longer than
5358 * that probably doesn't have much to worry about from
5359 * people who find out how long their password is!
5361 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
5362 ssh2_pkt_addstring(ssh
, s
->username
);
5363 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
5364 ssh2_pkt_addstring(ssh
, "password");
5365 ssh2_pkt_addbool(ssh
, FALSE
);
5366 ssh2_pkt_addstring(ssh
, s
->password
);
5367 memset(s
->password
, 0, sizeof(s
->password
));
5368 ssh2_pkt_defer(ssh
);
5370 * We'll include a string that's an exact multiple of the
5371 * cipher block size. If the cipher is NULL for some
5372 * reason, we don't do this trick at all because we gain
5375 if (ssh
->cscipher
) {
5378 stringlen
= (256 - ssh
->deferred_len
);
5379 stringlen
+= ssh
->cscipher
->blksize
- 1;
5380 stringlen
-= (stringlen
% ssh
->cscipher
->blksize
);
5383 * Temporarily disable actual compression,
5384 * so we can guarantee to get this string
5385 * exactly the length we want it. The
5386 * compression-disabling routine should
5387 * return an integer indicating how many
5388 * bytes we should adjust our string length
5392 ssh
->cscomp
->disable_compression(ssh
->cs_comp_ctx
);
5394 ssh2_pkt_init(ssh
, SSH2_MSG_IGNORE
);
5395 ssh2_pkt_addstring_start(ssh
);
5396 for (i
= 0; i
< stringlen
; i
++) {
5397 char c
= (char) random_byte();
5398 ssh2_pkt_addstring_data(ssh
, &c
, 1);
5400 ssh2_pkt_defer(ssh
);
5402 ssh_pkt_defersend(ssh
);
5403 logevent("Sent password");
5404 s
->type
= AUTH_TYPE_PASSWORD
;
5405 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
5406 if (s
->curr_prompt
== 0) {
5407 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_INFO_RESPONSE
);
5408 ssh2_pkt_adduint32(ssh
, s
->num_prompts
);
5410 if (s
->need_pw
) { /* only add pw if we just got one! */
5411 ssh2_pkt_addstring(ssh
, s
->password
);
5412 memset(s
->password
, 0, sizeof(s
->password
));
5415 if (s
->curr_prompt
>= s
->num_prompts
) {
5419 * If there are prompts remaining, we set
5420 * `gotit' so that we won't attempt to get
5421 * another packet. Then we go back round the
5422 * loop and will end up retrieving another
5423 * prompt out of the existing packet. Funky or
5428 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
5430 c_write_str(ssh
, "No supported authentication methods"
5431 " left to try!\r\n");
5432 logevent("No supported authentications offered."
5434 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
5435 ssh2_pkt_adduint32(ssh
, SSH2_DISCONNECT_BY_APPLICATION
);
5436 ssh2_pkt_addstring(ssh
, "No supported authentication"
5437 " methods available");
5438 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
5440 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5444 } while (!s
->we_are_in
);
5447 * Now we're authenticated for the connection protocol. The
5448 * connection protocol will automatically have started at this
5449 * point; there's no need to send SERVICE_REQUEST.
5453 * So now create a channel with a session in it.
5455 ssh
->channels
= newtree234(ssh_channelcmp
);
5456 ssh
->mainchan
= snew(struct ssh_channel
);
5457 ssh
->mainchan
->ssh
= ssh
;
5458 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
5459 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN
);
5460 ssh2_pkt_addstring(ssh
, "session");
5461 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->localid
);
5462 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5463 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
5464 ssh2_pkt_adduint32(ssh
, 0x4000UL
); /* our max pkt size */
5466 crWaitUntilV(ispkt
);
5467 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
5468 bombout(("Server refused to open a session"));
5470 /* FIXME: error data comes back in FAILURE packet */
5472 if (ssh_pkt_getuint32(ssh
) != ssh
->mainchan
->localid
) {
5473 bombout(("Server's channel confirmation cited wrong channel"));
5476 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(ssh
);
5477 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
5478 ssh
->mainchan
->closes
= 0;
5479 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(ssh
);
5480 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(ssh
);
5481 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
5482 add234(ssh
->channels
, ssh
->mainchan
);
5483 logevent("Opened channel for session");
5486 * Potentially enable X11 forwarding.
5488 if (ssh
->cfg
.x11_forward
) {
5489 char proto
[20], data
[64];
5490 logevent("Requesting X11 forwarding");
5491 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
5492 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
5493 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
5494 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5495 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
5496 ssh2_pkt_addstring(ssh
, "x11-req");
5497 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5498 ssh2_pkt_addbool(ssh
, 0); /* many connections */
5499 ssh2_pkt_addstring(ssh
, proto
);
5500 ssh2_pkt_addstring(ssh
, data
);
5501 ssh2_pkt_adduint32(ssh
, x11_get_screen_number(ssh
->cfg
.x11_display
));
5505 crWaitUntilV(ispkt
);
5506 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5507 unsigned i
= ssh_pkt_getuint32(ssh
);
5508 struct ssh_channel
*c
;
5509 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5511 continue; /* nonexistent channel */
5512 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
5514 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5516 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5517 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5518 bombout(("Unexpected response to X11 forwarding request:"
5519 " packet type %d", ssh
->pktin
.type
));
5522 logevent("X11 forwarding refused");
5524 logevent("X11 forwarding enabled");
5525 ssh
->X11_fwd_enabled
= TRUE
;
5530 * Enable port forwardings.
5535 int sport
,dport
,sserv
,dserv
;
5536 char sports
[256], dports
[256], saddr
[256], host
[256];
5538 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
5539 /* Add port forwardings. */
5540 ssh
->portfwd_strptr
= ssh
->cfg
.portfwd
;
5541 while (*ssh
->portfwd_strptr
) {
5542 type
= *ssh
->portfwd_strptr
++;
5545 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= '\t') {
5546 if (*ssh
->portfwd_strptr
== ':') {
5548 * We've seen a colon in the middle of the
5549 * source port number. This means that
5550 * everything we've seen until now is the
5551 * source _address_, so we'll move it into
5552 * saddr and start sports from the beginning
5555 ssh
->portfwd_strptr
++;
5557 strcpy(saddr
, sports
);
5560 if (n
< 255) sports
[n
++] = *ssh
->portfwd_strptr
++;
5564 if (*ssh
->portfwd_strptr
== '\t')
5565 ssh
->portfwd_strptr
++;
5567 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= ':') {
5568 if (n
< 255) host
[n
++] = *ssh
->portfwd_strptr
++;
5571 if (*ssh
->portfwd_strptr
== ':')
5572 ssh
->portfwd_strptr
++;
5574 while (*ssh
->portfwd_strptr
) {
5575 if (n
< 255) dports
[n
++] = *ssh
->portfwd_strptr
++;
5578 ssh
->portfwd_strptr
++;
5579 dport
= atoi(dports
);
5583 dport
= net_service_lookup(dports
);
5585 logeventf(ssh
, "Service lookup failed for destination"
5586 " port \"%s\"", dports
);
5590 while (*ssh
->portfwd_strptr
) ssh
->portfwd_strptr
++;
5592 ssh
->portfwd_strptr
++; /* eat the NUL and move to next one */
5594 sport
= atoi(sports
);
5598 sport
= net_service_lookup(sports
);
5600 logeventf(ssh
, "Service lookup failed for source"
5601 " port \"%s\"", sports
);
5604 if (sport
&& dport
) {
5606 pfd_addforward(host
, dport
, *saddr ? saddr
: NULL
,
5607 sport
, ssh
, &ssh
->cfg
);
5608 logeventf(ssh
, "Local port %.*s%.*s%.*s%.*s%d%.*s"
5609 " forwarding to %s:%.*s%.*s%d%.*s",
5610 (int)(*saddr?
strlen(saddr
):0), *saddr?saddr
:NULL
,
5611 (int)(*saddr?
1:0), ":",
5612 (int)(sserv ?
strlen(sports
) : 0), sports
,
5613 sserv
, "(", sport
, sserv
, ")",
5615 (int)(dserv ?
strlen(dports
) : 0), dports
,
5616 dserv
, "(", dport
, dserv
, ")");
5617 } else if (type
== 'D') {
5618 pfd_addforward(NULL
, -1, *saddr ? saddr
: NULL
,
5619 sport
, ssh
, &ssh
->cfg
);
5620 logeventf(ssh
, "Local port %.*s%.*s%.*s%.*s%d%.*s"
5621 " doing SOCKS dynamic forwarding",
5622 (int)(*saddr?
strlen(saddr
):0), *saddr?saddr
:NULL
,
5623 (int)(*saddr?
1:0), ":",
5624 (int)(sserv ?
strlen(sports
) : 0), sports
,
5625 sserv
, "(", sport
, sserv
, ")");
5627 struct ssh_rportfwd
*pf
;
5628 pf
= snew(struct ssh_rportfwd
);
5629 strcpy(pf
->dhost
, host
);
5632 if (add234(ssh
->rportfwds
, pf
) != pf
) {
5633 logeventf(ssh
, "Duplicate remote port forwarding"
5634 " to %s:%d", host
, dport
);
5637 logeventf(ssh
, "Requesting remote port "
5638 "%.*s%.*s%.*s%.*s%d%.*s"
5639 " forward to %s:%.*s%.*s%d%.*s",
5640 (int)(*saddr?
strlen(saddr
):0),
5642 (int)(*saddr?
1:0), ":",
5643 (int)(sserv ?
strlen(sports
) : 0), sports
,
5644 sserv
, "(", sport
, sserv
, ")",
5646 (int)(dserv ?
strlen(dports
) : 0), dports
,
5647 dserv
, "(", dport
, dserv
, ")");
5648 ssh2_pkt_init(ssh
, SSH2_MSG_GLOBAL_REQUEST
);
5649 ssh2_pkt_addstring(ssh
, "tcpip-forward");
5650 ssh2_pkt_addbool(ssh
, 1);/* want reply */
5652 ssh2_pkt_addstring(ssh
, saddr
);
5653 if (ssh
->cfg
.rport_acceptall
)
5654 ssh2_pkt_addstring(ssh
, "0.0.0.0");
5656 ssh2_pkt_addstring(ssh
, "127.0.0.1");
5657 ssh2_pkt_adduint32(ssh
, sport
);
5661 crWaitUntilV(ispkt
);
5662 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5663 unsigned i
= ssh_pkt_getuint32(ssh
);
5664 struct ssh_channel
*c
;
5665 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5667 continue;/* nonexistent channel */
5668 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
5670 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5672 if (ssh
->pktin
.type
!= SSH2_MSG_REQUEST_SUCCESS
) {
5673 if (ssh
->pktin
.type
!= SSH2_MSG_REQUEST_FAILURE
) {
5674 bombout(("Unexpected response to port "
5675 "forwarding request: packet type %d",
5679 logevent("Server refused this port forwarding");
5681 logevent("Remote port forwarding enabled");
5690 * Potentially enable agent forwarding.
5692 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
5693 logevent("Requesting OpenSSH-style agent forwarding");
5694 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5695 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
5696 ssh2_pkt_addstring(ssh
, "auth-agent-req@openssh.com");
5697 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5701 crWaitUntilV(ispkt
);
5702 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5703 unsigned i
= ssh_pkt_getuint32(ssh
);
5704 struct ssh_channel
*c
;
5705 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5707 continue; /* nonexistent channel */
5708 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
5710 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5712 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5713 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5714 bombout(("Unexpected response to agent forwarding request:"
5715 " packet type %d", ssh
->pktin
.type
));
5718 logevent("Agent forwarding refused");
5720 logevent("Agent forwarding enabled");
5721 ssh
->agentfwd_enabled
= TRUE
;
5726 * Now allocate a pty for the session.
5728 if (!ssh
->cfg
.nopty
) {
5729 /* Unpick the terminal-speed string. */
5730 /* XXX perhaps we should allow no speeds to be sent. */
5731 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
5732 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
5733 /* Build the pty request. */
5734 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5735 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
); /* recipient channel */
5736 ssh2_pkt_addstring(ssh
, "pty-req");
5737 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5738 ssh2_pkt_addstring(ssh
, ssh
->cfg
.termtype
);
5739 ssh2_pkt_adduint32(ssh
, ssh
->term_width
);
5740 ssh2_pkt_adduint32(ssh
, ssh
->term_height
);
5741 ssh2_pkt_adduint32(ssh
, 0); /* pixel width */
5742 ssh2_pkt_adduint32(ssh
, 0); /* pixel height */
5743 ssh2_pkt_addstring_start(ssh
);
5744 ssh2_pkt_addbyte(ssh
, 128); /* TTY_OP_ISPEED */
5745 ssh2_pkt_adduint32(ssh
, ssh
->ispeed
);
5746 ssh2_pkt_addbyte(ssh
, 129); /* TTY_OP_OSPEED */
5747 ssh2_pkt_adduint32(ssh
, ssh
->ospeed
);
5748 ssh2_pkt_addstring_data(ssh
, "\0", 1); /* TTY_OP_END */
5750 ssh
->state
= SSH_STATE_INTERMED
;
5753 crWaitUntilV(ispkt
);
5754 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5755 unsigned i
= ssh_pkt_getuint32(ssh
);
5756 struct ssh_channel
*c
;
5757 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5759 continue; /* nonexistent channel */
5760 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
5762 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5764 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5765 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5766 bombout(("Unexpected response to pty request:"
5767 " packet type %d", ssh
->pktin
.type
));
5770 c_write_str(ssh
, "Server refused to allocate pty\r\n");
5771 ssh
->editing
= ssh
->echoing
= 1;
5773 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
5774 ssh
->ospeed
, ssh
->ispeed
);
5777 ssh
->editing
= ssh
->echoing
= 1;
5781 * Start a shell or a remote command. We may have to attempt
5782 * this twice if the config data has provided a second choice
5789 if (ssh
->fallback_cmd
) {
5790 subsys
= ssh
->cfg
.ssh_subsys2
;
5791 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
5793 subsys
= ssh
->cfg
.ssh_subsys
;
5794 cmd
= ssh
->cfg
.remote_cmd_ptr
;
5797 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5798 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
); /* recipient channel */
5800 ssh2_pkt_addstring(ssh
, "subsystem");
5801 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5802 ssh2_pkt_addstring(ssh
, cmd
);
5804 ssh2_pkt_addstring(ssh
, "exec");
5805 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5806 ssh2_pkt_addstring(ssh
, cmd
);
5808 ssh2_pkt_addstring(ssh
, "shell");
5809 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5813 crWaitUntilV(ispkt
);
5814 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5815 unsigned i
= ssh_pkt_getuint32(ssh
);
5816 struct ssh_channel
*c
;
5817 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5819 continue; /* nonexistent channel */
5820 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
5822 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5823 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5824 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5825 bombout(("Unexpected response to shell/command request:"
5826 " packet type %d", ssh
->pktin
.type
));
5830 * We failed to start the command. If this is the
5831 * fallback command, we really are finished; if it's
5832 * not, and if the fallback command exists, try falling
5833 * back to it before complaining.
5835 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
5836 logevent("Primary command failed; attempting fallback");
5837 ssh
->fallback_cmd
= TRUE
;
5840 bombout(("Server refused to start a shell/command"));
5843 logevent("Started a shell/command");
5848 ssh
->state
= SSH_STATE_SESSION
;
5849 if (ssh
->size_needed
)
5850 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
5851 if (ssh
->eof_needed
)
5852 ssh_special(ssh
, TS_EOF
);
5858 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
5862 s
->try_send
= FALSE
;
5864 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
5865 ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
5868 unsigned i
= ssh_pkt_getuint32(ssh
);
5869 struct ssh_channel
*c
;
5870 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5872 continue; /* nonexistent channel */
5873 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5874 ssh_pkt_getuint32(ssh
) != SSH2_EXTENDED_DATA_STDERR
)
5875 continue; /* extended but not stderr */
5876 ssh_pkt_getstring(ssh
, &data
, &length
);
5879 c
->v
.v2
.locwindow
-= length
;
5881 case CHAN_MAINSESSION
:
5883 from_backend(ssh
->frontend
, ssh
->pktin
.type
==
5884 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5888 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5891 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5894 while (length
> 0) {
5895 if (c
->u
.a
.lensofar
< 4) {
5896 int l
= min(4 - c
->u
.a
.lensofar
, length
);
5897 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5901 c
->u
.a
.lensofar
+= l
;
5903 if (c
->u
.a
.lensofar
== 4) {
5905 4 + GET_32BIT(c
->u
.a
.msglen
);
5906 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
5908 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5910 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5912 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5914 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5918 c
->u
.a
.lensofar
+= l
;
5920 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5923 if (agent_query(c
->u
.a
.message
,
5926 ssh_agentf_callback
, c
))
5927 ssh_agentf_callback(c
, reply
, replylen
);
5928 sfree(c
->u
.a
.message
);
5929 c
->u
.a
.lensofar
= 0;
5936 * If we are not buffering too much data,
5937 * enlarge the window again at the remote side.
5939 if (bufsize
< OUR_V2_WINSIZE
)
5940 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5942 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
5943 unsigned i
= ssh_pkt_getuint32(ssh
);
5944 struct ssh_channel
*c
;
5946 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5948 continue; /* nonexistent channel */
5950 if (c
->type
== CHAN_X11
) {
5952 * Remote EOF on an X11 channel means we should
5953 * wrap up and close the channel ourselves.
5955 x11_close(c
->u
.x11
.s
);
5957 } else if (c
->type
== CHAN_AGENT
) {
5959 } else if (c
->type
== CHAN_SOCKDATA
) {
5960 pfd_close(c
->u
.pfd
.s
);
5963 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
5964 unsigned i
= ssh_pkt_getuint32(ssh
);
5965 struct ssh_channel
*c
;
5967 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5968 if (!c
|| ((int)c
->remoteid
) == -1) {
5969 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5970 c ?
"half-open" : "nonexistent", i
));
5973 /* Do pre-close processing on the channel. */
5975 case CHAN_MAINSESSION
:
5976 break; /* nothing to see here, move along */
5978 if (c
->u
.x11
.s
!= NULL
)
5979 x11_close(c
->u
.x11
.s
);
5986 if (c
->u
.pfd
.s
!= NULL
)
5987 pfd_close(c
->u
.pfd
.s
);
5991 if (c
->closes
== 0) {
5992 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_CLOSE
);
5993 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5996 del234(ssh
->channels
, c
);
5997 bufchain_clear(&c
->v
.v2
.outbuffer
);
6001 * See if that was the last channel left open.
6003 if (count234(ssh
->channels
) == 0) {
6004 logevent("All channels closed. Disconnecting");
6007 * We used to send SSH_MSG_DISCONNECT here,
6008 * because I'd believed that _every_ conforming
6009 * SSH2 connection had to end with a disconnect
6010 * being sent by at least one side; apparently
6011 * I was wrong and it's perfectly OK to
6012 * unceremoniously slam the connection shut
6013 * when you're done, and indeed OpenSSH feels
6014 * this is more polite than sending a
6015 * DISCONNECT. So now we don't.
6017 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
6018 ssh2_pkt_adduint32(ssh
, SSH2_DISCONNECT_BY_APPLICATION
);
6019 ssh2_pkt_addstring(ssh
, "All open channels closed");
6020 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
6023 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6026 continue; /* remote sends close; ignore (FIXME) */
6027 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
6028 unsigned i
= ssh_pkt_getuint32(ssh
);
6029 struct ssh_channel
*c
;
6030 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6031 if (!c
|| c
->closes
)
6032 continue; /* nonexistent or closing channel */
6033 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
6035 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
6036 unsigned i
= ssh_pkt_getuint32(ssh
);
6037 struct ssh_channel
*c
;
6038 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6040 continue; /* nonexistent channel */
6041 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
6042 continue; /* dunno why they're confirming this */
6043 c
->remoteid
= ssh_pkt_getuint32(ssh
);
6044 c
->type
= CHAN_SOCKDATA
;
6045 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(ssh
);
6046 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(ssh
);
6048 pfd_confirm(c
->u
.pfd
.s
);
6051 * We have a pending close on this channel,
6052 * which we decided on before the server acked
6053 * the channel open. So now we know the
6054 * remoteid, we can close it again.
6056 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_CLOSE
);
6057 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
6060 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_OPEN_FAILURE
) {
6061 unsigned i
= ssh_pkt_getuint32(ssh
);
6062 struct ssh_channel
*c
;
6063 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6065 continue; /* nonexistent channel */
6066 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
6067 continue; /* dunno why they're failing this */
6069 logevent("Forwarded connection refused by server");
6071 pfd_close(c
->u
.pfd
.s
);
6073 del234(ssh
->channels
, c
);
6075 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
6078 int typelen
, want_reply
;
6079 struct ssh_channel
*c
;
6081 localid
= ssh_pkt_getuint32(ssh
);
6082 ssh_pkt_getstring(ssh
, &type
, &typelen
);
6083 want_reply
= ssh2_pkt_getbool(ssh
);
6086 * First, check that the channel exists. Otherwise,
6087 * we can instantly disconnect with a rude message.
6089 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
6092 sprintf(buf
, "Received channel request for nonexistent"
6093 " channel %d", localid
);
6095 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
6096 ssh2_pkt_adduint32(ssh
, SSH2_DISCONNECT_BY_APPLICATION
);
6097 ssh2_pkt_addstring(ssh
, buf
);
6098 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
6100 connection_fatal(ssh
->frontend
, "%s", buf
);
6101 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6106 * Having got the channel number, we now look at
6107 * the request type string to see if it's something
6110 if (typelen
== 11 && !memcmp(type
, "exit-status", 11) &&
6111 c
== ssh
->mainchan
) {
6112 /* We recognise "exit-status" on the primary channel. */
6114 ssh
->exitcode
= ssh_pkt_getuint32(ssh
);
6115 sprintf(buf
, "Server sent command exit status %d",
6119 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_SUCCESS
);
6120 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
6125 * This is a channel request we don't know
6126 * about, so we now either ignore the request
6127 * or respond with CHANNEL_FAILURE, depending
6131 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_FAILURE
);
6132 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
6136 } else if (ssh
->pktin
.type
== SSH2_MSG_GLOBAL_REQUEST
) {
6138 int typelen
, want_reply
;
6140 ssh_pkt_getstring(ssh
, &type
, &typelen
);
6141 want_reply
= ssh2_pkt_getbool(ssh
);
6144 * We currently don't support any global requests
6145 * at all, so we either ignore the request or
6146 * respond with REQUEST_FAILURE, depending on
6150 ssh2_pkt_init(ssh
, SSH2_MSG_REQUEST_FAILURE
);
6153 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
6160 struct ssh_channel
*c
;
6161 unsigned remid
, winsize
, pktsize
;
6162 ssh_pkt_getstring(ssh
, &type
, &typelen
);
6163 c
= snew(struct ssh_channel
);
6166 remid
= ssh_pkt_getuint32(ssh
);
6167 winsize
= ssh_pkt_getuint32(ssh
);
6168 pktsize
= ssh_pkt_getuint32(ssh
);
6170 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
6173 ssh_pkt_getstring(ssh
, &peeraddr
, &peeraddrlen
);
6174 addrstr
= snewn(peeraddrlen
+1, char);
6175 memcpy(addrstr
, peeraddr
, peeraddrlen
);
6176 addrstr
[peeraddrlen
] = '\0';
6177 peerport
= ssh_pkt_getuint32(ssh
);
6179 logeventf(ssh
, "Received X11 connect request from %s:%d",
6182 if (!ssh
->X11_fwd_enabled
)
6183 error
= "X11 forwarding is not enabled";
6184 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
6185 ssh
->x11auth
, addrstr
, peerport
,
6186 &ssh
->cfg
) != NULL
) {
6187 error
= "Unable to open an X11 connection";
6189 logevent("Opening X11 forward connection succeeded");
6194 } else if (typelen
== 15 &&
6195 !memcmp(type
, "forwarded-tcpip", 15)) {
6196 struct ssh_rportfwd pf
, *realpf
;
6199 ssh_pkt_getstring(ssh
, &dummy
, &dummylen
);/* skip address */
6200 pf
.sport
= ssh_pkt_getuint32(ssh
);
6201 ssh_pkt_getstring(ssh
, &peeraddr
, &peeraddrlen
);
6202 peerport
= ssh_pkt_getuint32(ssh
);
6203 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
6204 logeventf(ssh
, "Received remote port %d open request "
6205 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
6206 if (realpf
== NULL
) {
6207 error
= "Remote port is not recognised";
6209 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
6213 logeventf(ssh
, "Attempting to forward remote port to "
6214 "%s:%d", realpf
->dhost
, realpf
->dport
);
6216 logeventf(ssh
, "Port open failed: %s", e
);
6217 error
= "Port open failed";
6219 logevent("Forwarded port opened successfully");
6220 c
->type
= CHAN_SOCKDATA
;
6223 } else if (typelen
== 22 &&
6224 !memcmp(type
, "auth-agent@openssh.com", 3)) {
6225 if (!ssh
->agentfwd_enabled
)
6226 error
= "Agent forwarding is not enabled";
6228 c
->type
= CHAN_AGENT
; /* identify channel type */
6229 c
->u
.a
.lensofar
= 0;
6232 error
= "Unsupported channel type requested";
6235 c
->remoteid
= remid
;
6237 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN_FAILURE
);
6238 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
6239 ssh2_pkt_adduint32(ssh
, SSH2_OPEN_CONNECT_FAILED
);
6240 ssh2_pkt_addstring(ssh
, error
);
6241 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
6243 logeventf(ssh
, "Rejected channel open: %s", error
);
6246 c
->localid
= alloc_channel_id(ssh
);
6248 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6249 c
->v
.v2
.remwindow
= winsize
;
6250 c
->v
.v2
.remmaxpkt
= pktsize
;
6251 bufchain_init(&c
->v
.v2
.outbuffer
);
6252 add234(ssh
->channels
, c
);
6253 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
6254 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
6255 ssh2_pkt_adduint32(ssh
, c
->localid
);
6256 ssh2_pkt_adduint32(ssh
, c
->v
.v2
.locwindow
);
6257 ssh2_pkt_adduint32(ssh
, 0x4000UL
); /* our max pkt size */
6261 bombout(("Strange packet received: type %d", ssh
->pktin
.type
));
6266 * We have spare data. Add it to the channel buffer.
6268 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
6273 struct ssh_channel
*c
;
6275 * Try to send data on all channels if we can.
6277 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
6280 continue; /* don't send on closing channels */
6281 bufsize
= ssh2_try_send(c
);
6284 case CHAN_MAINSESSION
:
6285 /* stdin need not receive an unthrottle
6286 * notification since it will be polled */
6289 x11_unthrottle(c
->u
.x11
.s
);
6292 /* agent sockets are request/response and need no
6293 * buffer management */
6296 pfd_unthrottle(c
->u
.pfd
.s
);
6308 * Handle the top-level SSH2 protocol.
6310 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
6312 if (do_ssh2_transport(ssh
, in
, inlen
, ispkt
) == 0)
6314 do_ssh2_authconn(ssh
, in
, inlen
, ispkt
);
6318 * Called to set up the connection.
6320 * Returns an error message, or NULL on success.
6322 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
6324 char *host
, int port
, char **realhost
, int nodelay
,
6330 ssh
= snew(struct ssh_tag
);
6331 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
6332 ssh
->version
= 0; /* when not ready yet */
6335 ssh
->v1_cipher_ctx
= NULL
;
6336 ssh
->crcda_ctx
= NULL
;
6337 ssh
->cscipher
= NULL
;
6338 ssh
->cs_cipher_ctx
= NULL
;
6339 ssh
->sccipher
= NULL
;
6340 ssh
->sc_cipher_ctx
= NULL
;
6342 ssh
->cs_mac_ctx
= NULL
;
6344 ssh
->sc_mac_ctx
= NULL
;
6346 ssh
->cs_comp_ctx
= NULL
;
6348 ssh
->sc_comp_ctx
= NULL
;
6350 ssh
->kex_ctx
= NULL
;
6351 ssh
->hostkey
= NULL
;
6353 ssh
->state
= SSH_STATE_PREPACKET
;
6354 ssh
->size_needed
= FALSE
;
6355 ssh
->eof_needed
= FALSE
;
6359 static const struct Packet empty
= { 0, 0, NULL
, NULL
, 0 };
6360 ssh
->pktin
= ssh
->pktout
= empty
;
6362 ssh
->deferred_send_data
= NULL
;
6363 ssh
->deferred_len
= 0;
6364 ssh
->deferred_size
= 0;
6365 ssh
->fallback_cmd
= 0;
6367 ssh
->x11auth
= NULL
;
6368 ssh
->v1_compressing
= FALSE
;
6369 ssh
->v2_outgoing_sequence
= 0;
6370 ssh
->ssh1_rdpkt_crstate
= 0;
6371 ssh
->ssh2_rdpkt_crstate
= 0;
6372 ssh
->do_ssh_init_crstate
= 0;
6373 ssh
->ssh_gotdata_crstate
= 0;
6374 ssh
->ssh1_protocol_crstate
= 0;
6375 ssh
->do_ssh1_login_crstate
= 0;
6376 ssh
->do_ssh2_transport_crstate
= 0;
6377 ssh
->do_ssh2_authconn_crstate
= 0;
6378 ssh
->do_ssh_init_state
= NULL
;
6379 ssh
->do_ssh1_login_state
= NULL
;
6380 ssh
->do_ssh2_transport_state
= NULL
;
6381 ssh
->do_ssh2_authconn_state
= NULL
;
6382 ssh
->mainchan
= NULL
;
6383 ssh
->throttled_all
= 0;
6384 ssh
->v1_stdout_throttling
= 0;
6386 *backend_handle
= ssh
;
6389 if (crypto_startup() == 0)
6390 return "Microsoft high encryption pack not installed!";
6393 ssh
->frontend
= frontend_handle
;
6394 ssh
->term_width
= ssh
->cfg
.width
;
6395 ssh
->term_height
= ssh
->cfg
.height
;
6397 ssh
->channels
= NULL
;
6398 ssh
->rportfwds
= NULL
;
6403 ssh
->v1_throttle_count
= 0;
6404 ssh
->overall_bufsize
= 0;
6405 ssh
->fallback_cmd
= 0;
6407 ssh
->protocol
= NULL
;
6409 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
6416 static void ssh_free(void *handle
)
6418 Ssh ssh
= (Ssh
) handle
;
6419 struct ssh_channel
*c
;
6420 struct ssh_rportfwd
*pf
;
6422 if (ssh
->v1_cipher_ctx
)
6423 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
6424 if (ssh
->cs_cipher_ctx
)
6425 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
6426 if (ssh
->sc_cipher_ctx
)
6427 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
6428 if (ssh
->cs_mac_ctx
)
6429 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
6430 if (ssh
->sc_mac_ctx
)
6431 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
6432 if (ssh
->cs_comp_ctx
) {
6434 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
6436 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
6438 if (ssh
->sc_comp_ctx
) {
6440 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
6442 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
6445 dh_cleanup(ssh
->kex_ctx
);
6446 sfree(ssh
->savedhost
);
6448 if (ssh
->channels
) {
6449 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
6452 if (c
->u
.x11
.s
!= NULL
)
6453 x11_close(c
->u
.x11
.s
);
6456 if (c
->u
.pfd
.s
!= NULL
)
6457 pfd_close(c
->u
.pfd
.s
);
6462 freetree234(ssh
->channels
);
6465 if (ssh
->rportfwds
) {
6466 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
6468 freetree234(ssh
->rportfwds
);
6470 sfree(ssh
->deferred_send_data
);
6472 x11_free_auth(ssh
->x11auth
);
6473 sfree(ssh
->do_ssh_init_state
);
6474 sfree(ssh
->do_ssh1_login_state
);
6475 sfree(ssh
->do_ssh2_transport_state
);
6476 sfree(ssh
->do_ssh2_authconn_state
);
6477 if (ssh
->pktout
.data
) {
6478 sfree(ssh
->pktout
.data
);
6479 ssh
->pktout
.data
= NULL
;
6481 if (ssh
->pktin
.data
) {
6482 sfree(ssh
->pktin
.data
);
6483 ssh
->pktin
.data
= NULL
;
6485 if (ssh
->crcda_ctx
) {
6486 crcda_free_context(ssh
->crcda_ctx
);
6487 ssh
->crcda_ctx
= NULL
;
6495 * Reconfigure the SSH backend.
6497 * Currently, this function does nothing very useful. In future,
6498 * however, we could do some handy things with it. For example, we
6499 * could make the port forwarding configurer active in the Change
6500 * Settings box, and this routine could close down existing
6501 * forwardings and open up new ones in response to changes.
6503 static void ssh_reconfig(void *handle
, Config
*cfg
)
6505 Ssh ssh
= (Ssh
) handle
;
6506 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
6510 * Called to send data down the Telnet connection.
6512 static int ssh_send(void *handle
, char *buf
, int len
)
6514 Ssh ssh
= (Ssh
) handle
;
6516 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
6519 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
6521 return ssh_sendbuffer(ssh
);
6525 * Called to query the current amount of buffered stdin data.
6527 static int ssh_sendbuffer(void *handle
)
6529 Ssh ssh
= (Ssh
) handle
;
6532 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
6536 * If the SSH socket itself has backed up, add the total backup
6537 * size on that to any individual buffer on the stdin channel.
6540 if (ssh
->throttled_all
)
6541 override_value
= ssh
->overall_bufsize
;
6543 if (ssh
->version
== 1) {
6544 return override_value
;
6545 } else if (ssh
->version
== 2) {
6546 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
6547 return override_value
;
6549 return (override_value
+
6550 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
6557 * Called to set the size of the window from SSH's POV.
6559 static void ssh_size(void *handle
, int width
, int height
)
6561 Ssh ssh
= (Ssh
) handle
;
6563 ssh
->term_width
= width
;
6564 ssh
->term_height
= height
;
6566 switch (ssh
->state
) {
6567 case SSH_STATE_BEFORE_SIZE
:
6568 case SSH_STATE_PREPACKET
:
6569 case SSH_STATE_CLOSED
:
6570 break; /* do nothing */
6571 case SSH_STATE_INTERMED
:
6572 ssh
->size_needed
= TRUE
; /* buffer for later */
6574 case SSH_STATE_SESSION
:
6575 if (!ssh
->cfg
.nopty
) {
6576 if (ssh
->version
== 1) {
6577 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
6578 PKT_INT
, ssh
->term_height
,
6579 PKT_INT
, ssh
->term_width
,
6580 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
6582 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
6583 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
6584 ssh2_pkt_addstring(ssh
, "window-change");
6585 ssh2_pkt_addbool(ssh
, 0);
6586 ssh2_pkt_adduint32(ssh
, ssh
->term_width
);
6587 ssh2_pkt_adduint32(ssh
, ssh
->term_height
);
6588 ssh2_pkt_adduint32(ssh
, 0);
6589 ssh2_pkt_adduint32(ssh
, 0);
6598 * Return a list of the special codes that make sense in this
6601 static const struct telnet_special
*ssh_get_specials(void *handle
)
6603 Ssh ssh
= (Ssh
) handle
;
6605 if (ssh
->version
== 1) {
6606 static const struct telnet_special ssh1_specials
[] = {
6607 {"IGNORE message", TS_NOP
},
6610 return ssh1_specials
;
6611 } else if (ssh
->version
== 2) {
6612 static const struct telnet_special ssh2_specials
[] = {
6614 {"IGNORE message", TS_NOP
},
6617 return ssh2_specials
;
6623 * Send Telnet special codes. TS_EOF is useful for `plink', so you
6624 * can send an EOF and collect resulting output (e.g. `plink
6627 static void ssh_special(void *handle
, Telnet_Special code
)
6629 Ssh ssh
= (Ssh
) handle
;
6631 if (code
== TS_EOF
) {
6632 if (ssh
->state
!= SSH_STATE_SESSION
) {
6634 * Buffer the EOF in case we are pre-SESSION, so we can
6635 * send it as soon as we reach SESSION.
6638 ssh
->eof_needed
= TRUE
;
6641 if (ssh
->version
== 1) {
6642 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
6644 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_EOF
);
6645 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
6648 logevent("Sent EOF message");
6649 } else if (code
== TS_PING
|| code
== TS_NOP
) {
6650 if (ssh
->state
== SSH_STATE_CLOSED
6651 || ssh
->state
== SSH_STATE_PREPACKET
) return;
6652 if (ssh
->version
== 1) {
6653 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
6654 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
6656 ssh2_pkt_init(ssh
, SSH2_MSG_IGNORE
);
6657 ssh2_pkt_addstring_start(ssh
);
6660 } else if (code
== TS_BRK
) {
6661 if (ssh
->state
== SSH_STATE_CLOSED
6662 || ssh
->state
== SSH_STATE_PREPACKET
) return;
6663 if (ssh
->version
== 1) {
6664 logevent("Unable to send BREAK signal in SSH1");
6666 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
6667 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
6668 ssh2_pkt_addstring(ssh
, "break");
6669 ssh2_pkt_addbool(ssh
, 0);
6670 ssh2_pkt_adduint32(ssh
, 0); /* default break length */
6678 void *new_sock_channel(void *handle
, Socket s
)
6680 Ssh ssh
= (Ssh
) handle
;
6681 struct ssh_channel
*c
;
6682 c
= snew(struct ssh_channel
);
6686 c
->remoteid
= -1; /* to be set when open confirmed */
6687 c
->localid
= alloc_channel_id(ssh
);
6689 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
6691 bufchain_init(&c
->v
.v2
.outbuffer
);
6692 add234(ssh
->channels
, c
);
6698 * This is called when stdout/stderr (the entity to which
6699 * from_backend sends data) manages to clear some backlog.
6701 static void ssh_unthrottle(void *handle
, int bufsize
)
6703 Ssh ssh
= (Ssh
) handle
;
6704 if (ssh
->version
== 1) {
6705 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
6706 ssh
->v1_stdout_throttling
= 0;
6707 ssh1_throttle(ssh
, -1);
6710 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
6711 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
6715 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
6717 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
6720 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
6722 if (ssh
->version
== 1) {
6723 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
6724 PKT_INT
, c
->localid
,
6727 //PKT_STR, <org:orgport>,
6730 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN
);
6731 ssh2_pkt_addstring(ssh
, "direct-tcpip");
6732 ssh2_pkt_adduint32(ssh
, c
->localid
);
6733 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6734 ssh2_pkt_adduint32(ssh
, c
->v
.v2
.locwindow
);/* our window size */
6735 ssh2_pkt_adduint32(ssh
, 0x4000UL
); /* our max pkt size */
6736 ssh2_pkt_addstring(ssh
, hostname
);
6737 ssh2_pkt_adduint32(ssh
, port
);
6739 * We make up values for the originator data; partly it's
6740 * too much hassle to keep track, and partly I'm not
6741 * convinced the server should be told details like that
6742 * about my local network configuration.
6744 ssh2_pkt_addstring(ssh
, "client-side-connection");
6745 ssh2_pkt_adduint32(ssh
, 0);
6751 static Socket
ssh_socket(void *handle
)
6753 Ssh ssh
= (Ssh
) handle
;
6757 static int ssh_sendok(void *handle
)
6759 Ssh ssh
= (Ssh
) handle
;
6760 return ssh
->send_ok
;
6763 static int ssh_ldisc(void *handle
, int option
)
6765 Ssh ssh
= (Ssh
) handle
;
6766 if (option
== LD_ECHO
)
6767 return ssh
->echoing
;
6768 if (option
== LD_EDIT
)
6769 return ssh
->editing
;
6773 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
6775 Ssh ssh
= (Ssh
) handle
;
6779 static void ssh_provide_logctx(void *handle
, void *logctx
)
6781 Ssh ssh
= (Ssh
) handle
;
6782 ssh
->logctx
= logctx
;
6785 static int ssh_return_exitcode(void *handle
)
6787 Ssh ssh
= (Ssh
) handle
;
6791 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
6795 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
6796 * that fails. This variable is the means by which scp.c can reach
6797 * into the SSH code and find out which one it got.
6799 extern int ssh_fallback_cmd(void *handle
)
6801 Ssh ssh
= (Ssh
) handle
;
6802 return ssh
->fallback_cmd
;
6805 Backend ssh_backend
= {
6815 ssh_return_exitcode
,