17 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
18 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
19 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
20 #define SSH1_CMSG_USER 4 /* 0x4 */
21 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
22 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
23 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
24 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
25 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
26 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
27 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
28 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
29 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
30 #define SSH1_SMSG_FAILURE 15 /* 0xf */
31 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
32 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
33 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
34 #define SSH1_CMSG_EOF 19 /* 0x13 */
35 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
36 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
37 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
38 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
39 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
40 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
41 #define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
42 #define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
43 #define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
44 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
45 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
46 #define SSH1_MSG_IGNORE 32 /* 0x20 */
47 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
48 #define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
49 #define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
50 #define SSH1_MSG_DEBUG 36 /* 0x24 */
51 #define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
52 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
53 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
54 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
55 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
56 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
57 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
59 #define SSH1_AUTH_TIS 5 /* 0x5 */
60 #define SSH1_AUTH_CCARD 16 /* 0x10 */
62 #define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
63 /* Mask for protoflags we will echo back to server if seen */
64 #define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
66 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
67 #define SSH2_MSG_IGNORE 2 /* 0x2 */
68 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
69 #define SSH2_MSG_DEBUG 4 /* 0x4 */
70 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
71 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
72 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
73 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
74 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
75 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
76 #define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
77 #define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
78 #define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
79 #define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
80 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
81 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
82 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
83 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
84 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
85 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
86 #define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
87 #define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
88 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
89 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
90 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
91 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
92 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
93 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
94 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
95 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
96 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
97 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
98 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
99 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
100 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
101 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
104 * Packet type contexts, so that ssh2_pkt_type can correctly decode
105 * the ambiguous type numbers back into the correct type strings.
107 #define SSH2_PKTCTX_DHGROUP1 0x0001
108 #define SSH2_PKTCTX_DHGEX 0x0002
109 #define SSH2_PKTCTX_PUBLICKEY 0x0010
110 #define SSH2_PKTCTX_PASSWORD 0x0020
111 #define SSH2_PKTCTX_KBDINTER 0x0040
112 #define SSH2_PKTCTX_AUTH_MASK 0x00F0
114 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
115 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
116 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
117 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
118 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
119 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
120 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
121 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
122 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
123 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
124 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
125 #define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
126 #define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
127 #define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
128 #define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
130 static const char *const ssh2_disconnect_reasons
[] = {
132 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
133 "SSH_DISCONNECT_PROTOCOL_ERROR",
134 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
135 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
136 "SSH_DISCONNECT_MAC_ERROR",
137 "SSH_DISCONNECT_COMPRESSION_ERROR",
138 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
139 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
140 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
141 "SSH_DISCONNECT_CONNECTION_LOST",
142 "SSH_DISCONNECT_BY_APPLICATION",
143 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
144 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
145 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
146 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
149 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
150 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
151 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
152 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
154 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
157 * Various remote-bug flags.
159 #define BUG_CHOKES_ON_SSH1_IGNORE 1
160 #define BUG_SSH2_HMAC 2
161 #define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
162 #define BUG_CHOKES_ON_RSA 8
163 #define BUG_SSH2_RSA_PADDING 16
164 #define BUG_SSH2_DERIVEKEY 32
165 #define BUG_SSH2_DH_GEX 64
166 #define BUG_SSH2_PK_SESSIONID 128
168 #define translate(x) if (type == x) return #x
169 #define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
170 static char *ssh1_pkt_type(int type
)
172 translate(SSH1_MSG_DISCONNECT
);
173 translate(SSH1_SMSG_PUBLIC_KEY
);
174 translate(SSH1_CMSG_SESSION_KEY
);
175 translate(SSH1_CMSG_USER
);
176 translate(SSH1_CMSG_AUTH_RSA
);
177 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE
);
178 translate(SSH1_CMSG_AUTH_RSA_RESPONSE
);
179 translate(SSH1_CMSG_AUTH_PASSWORD
);
180 translate(SSH1_CMSG_REQUEST_PTY
);
181 translate(SSH1_CMSG_WINDOW_SIZE
);
182 translate(SSH1_CMSG_EXEC_SHELL
);
183 translate(SSH1_CMSG_EXEC_CMD
);
184 translate(SSH1_SMSG_SUCCESS
);
185 translate(SSH1_SMSG_FAILURE
);
186 translate(SSH1_CMSG_STDIN_DATA
);
187 translate(SSH1_SMSG_STDOUT_DATA
);
188 translate(SSH1_SMSG_STDERR_DATA
);
189 translate(SSH1_CMSG_EOF
);
190 translate(SSH1_SMSG_EXIT_STATUS
);
191 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
);
192 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE
);
193 translate(SSH1_MSG_CHANNEL_DATA
);
194 translate(SSH1_MSG_CHANNEL_CLOSE
);
195 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
);
196 translate(SSH1_SMSG_X11_OPEN
);
197 translate(SSH1_CMSG_PORT_FORWARD_REQUEST
);
198 translate(SSH1_MSG_PORT_OPEN
);
199 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING
);
200 translate(SSH1_SMSG_AGENT_OPEN
);
201 translate(SSH1_MSG_IGNORE
);
202 translate(SSH1_CMSG_EXIT_CONFIRMATION
);
203 translate(SSH1_CMSG_X11_REQUEST_FORWARDING
);
204 translate(SSH1_CMSG_AUTH_RHOSTS_RSA
);
205 translate(SSH1_MSG_DEBUG
);
206 translate(SSH1_CMSG_REQUEST_COMPRESSION
);
207 translate(SSH1_CMSG_AUTH_TIS
);
208 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE
);
209 translate(SSH1_CMSG_AUTH_TIS_RESPONSE
);
210 translate(SSH1_CMSG_AUTH_CCARD
);
211 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE
);
212 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE
);
215 static char *ssh2_pkt_type(int pkt_ctx
, int type
)
217 translate(SSH2_MSG_DISCONNECT
);
218 translate(SSH2_MSG_IGNORE
);
219 translate(SSH2_MSG_UNIMPLEMENTED
);
220 translate(SSH2_MSG_DEBUG
);
221 translate(SSH2_MSG_SERVICE_REQUEST
);
222 translate(SSH2_MSG_SERVICE_ACCEPT
);
223 translate(SSH2_MSG_KEXINIT
);
224 translate(SSH2_MSG_NEWKEYS
);
225 translatec(SSH2_MSG_KEXDH_INIT
, SSH2_PKTCTX_DHGROUP1
);
226 translatec(SSH2_MSG_KEXDH_REPLY
, SSH2_PKTCTX_DHGROUP1
);
227 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST
, SSH2_PKTCTX_DHGEX
);
228 translatec(SSH2_MSG_KEX_DH_GEX_GROUP
, SSH2_PKTCTX_DHGEX
);
229 translatec(SSH2_MSG_KEX_DH_GEX_INIT
, SSH2_PKTCTX_DHGEX
);
230 translatec(SSH2_MSG_KEX_DH_GEX_REPLY
, SSH2_PKTCTX_DHGEX
);
231 translate(SSH2_MSG_USERAUTH_REQUEST
);
232 translate(SSH2_MSG_USERAUTH_FAILURE
);
233 translate(SSH2_MSG_USERAUTH_SUCCESS
);
234 translate(SSH2_MSG_USERAUTH_BANNER
);
235 translatec(SSH2_MSG_USERAUTH_PK_OK
, SSH2_PKTCTX_PUBLICKEY
);
236 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
, SSH2_PKTCTX_PASSWORD
);
237 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST
, SSH2_PKTCTX_KBDINTER
);
238 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE
, SSH2_PKTCTX_KBDINTER
);
239 translate(SSH2_MSG_GLOBAL_REQUEST
);
240 translate(SSH2_MSG_REQUEST_SUCCESS
);
241 translate(SSH2_MSG_REQUEST_FAILURE
);
242 translate(SSH2_MSG_CHANNEL_OPEN
);
243 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
244 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
245 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
246 translate(SSH2_MSG_CHANNEL_DATA
);
247 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA
);
248 translate(SSH2_MSG_CHANNEL_EOF
);
249 translate(SSH2_MSG_CHANNEL_CLOSE
);
250 translate(SSH2_MSG_CHANNEL_REQUEST
);
251 translate(SSH2_MSG_CHANNEL_SUCCESS
);
252 translate(SSH2_MSG_CHANNEL_FAILURE
);
258 #define GET_32BIT(cp) \
259 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
260 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
261 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
262 ((unsigned long)(unsigned char)(cp)[3]))
264 #define PUT_32BIT(cp, value) { \
265 (cp)[0] = (unsigned char)((value) >> 24); \
266 (cp)[1] = (unsigned char)((value) >> 16); \
267 (cp)[2] = (unsigned char)((value) >> 8); \
268 (cp)[3] = (unsigned char)(value); }
270 /* Enumeration values for fields in SSH-1 packets */
272 PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
,
273 /* These values are for communicating relevant semantics of
274 * fields to the packet logging code. */
275 PKTT_OTHER
, PKTT_PASSWORD
, PKTT_DATA
279 * Coroutine mechanics for the sillier bits of the code. If these
280 * macros look impenetrable to you, you might find it helpful to
283 * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
285 * which explains the theory behind these macros.
287 * In particular, if you are getting `case expression not constant'
288 * errors when building with MS Visual Studio, this is because MS's
289 * Edit and Continue debugging feature causes their compiler to
290 * violate ANSI C. To disable Edit and Continue debugging:
292 * - right-click ssh.c in the FileView
294 * - select the C/C++ tab and the General category
295 * - under `Debug info:', select anything _other_ than `Program
296 * Database for Edit and Continue'.
298 #define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
301 if (!ssh->t) ssh->t = snew(struct t); \
303 #define crFinish(z) } *crLine = 0; return (z); }
304 #define crFinishV } *crLine = 0; return; }
305 #define crReturn(z) \
307 *crLine =__LINE__; return (z); case __LINE__:;\
311 *crLine=__LINE__; return; case __LINE__:;\
313 #define crStop(z) do{ *crLine = 0; return (z); }while(0)
314 #define crStopV do{ *crLine = 0; return; }while(0)
315 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
316 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
318 typedef struct ssh_tag
*Ssh
;
320 static void ssh2_pkt_init(Ssh
, int pkt_type
);
321 static void ssh2_pkt_addbool(Ssh
, unsigned char value
);
322 static void ssh2_pkt_adduint32(Ssh
, unsigned long value
);
323 static void ssh2_pkt_addstring_start(Ssh
);
324 static void ssh2_pkt_addstring_str(Ssh
, char *data
);
325 static void ssh2_pkt_addstring_data(Ssh
, char *data
, int len
);
326 static void ssh2_pkt_addstring(Ssh
, char *data
);
327 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
);
328 static void ssh2_pkt_addmp(Ssh
, Bignum b
);
329 static int ssh2_pkt_construct(Ssh
);
330 static void ssh2_pkt_send(Ssh
);
331 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
332 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
335 * Buffer management constants. There are several of these for
336 * various different purposes:
338 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
339 * on a local data stream before we throttle the whole SSH
340 * connection (in SSH1 only). Throttling the whole connection is
341 * pretty drastic so we set this high in the hope it won't
344 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
345 * on the SSH connection itself before we defensively throttle
346 * _all_ local data streams. This is pretty drastic too (though
347 * thankfully unlikely in SSH2 since the window mechanism should
348 * ensure that the server never has any need to throttle its end
349 * of the connection), so we set this high as well.
351 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
355 #define SSH1_BUFFER_LIMIT 32768
356 #define SSH_MAX_BACKLOG 32768
357 #define OUR_V2_WINSIZE 16384
359 const static struct ssh_kex
*kex_algs
[] = {
360 &ssh_diffiehellman_gex
,
364 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
366 static void *nullmac_make_context(void)
370 static void nullmac_free_context(void *handle
)
373 static void nullmac_key(void *handle
, unsigned char *key
)
376 static void nullmac_generate(void *handle
, unsigned char *blk
, int len
,
380 static int nullmac_verify(void *handle
, unsigned char *blk
, int len
,
385 const static struct ssh_mac ssh_mac_none
= {
386 nullmac_make_context
, nullmac_free_context
, nullmac_key
,
387 nullmac_generate
, nullmac_verify
, "none", 0
389 const static struct ssh_mac
*macs
[] = {
390 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
392 const static struct ssh_mac
*buggymacs
[] = {
393 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
396 static void *ssh_comp_none_init(void)
400 static void ssh_comp_none_cleanup(void *handle
)
403 static int ssh_comp_none_block(void *handle
, unsigned char *block
, int len
,
404 unsigned char **outblock
, int *outlen
)
408 static int ssh_comp_none_disable(void *handle
)
412 const static struct ssh_compress ssh_comp_none
= {
414 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
415 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
416 ssh_comp_none_disable
, NULL
418 extern const struct ssh_compress ssh_zlib
;
419 const static struct ssh_compress
*compressions
[] = {
420 &ssh_zlib
, &ssh_comp_none
423 enum { /* channel types */
428 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
432 * 2-3-4 tree storing channels.
435 Ssh ssh
; /* pointer back to main context */
436 unsigned remoteid
, localid
;
439 * In SSH1, this value contains four bits:
441 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
442 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
443 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
444 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
446 * A channel is completely finished with when all four bits are set.
450 struct ssh1_data_channel
{
453 struct ssh2_data_channel
{
455 unsigned remwindow
, remmaxpkt
;
460 struct ssh_agent_channel
{
461 unsigned char *message
;
462 unsigned char msglen
[4];
463 unsigned lensofar
, totallen
;
465 struct ssh_x11_channel
{
468 struct ssh_pfd_channel
{
475 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
476 * 2 use this structure in different ways, reflecting SSH 2's
477 * altogether saner approach to port forwarding.
479 * In SSH 1, you arrange a remote forwarding by sending the server
480 * the remote port number, and the local destination host:port.
481 * When a connection comes in, the server sends you back that
482 * host:port pair, and you connect to it. This is a ready-made
483 * security hole if you're not on the ball: a malicious server
484 * could send you back _any_ host:port pair, so if you trustingly
485 * connect to the address it gives you then you've just opened the
486 * entire inside of your corporate network just by connecting
487 * through it to a dodgy SSH server. Hence, we must store a list of
488 * host:port pairs we _are_ trying to forward to, and reject a
489 * connection request from the server if it's not in the list.
491 * In SSH 2, each side of the connection minds its own business and
492 * doesn't send unnecessary information to the other. You arrange a
493 * remote forwarding by sending the server just the remote port
494 * number. When a connection comes in, the server tells you which
495 * of its ports was connected to; and _you_ have to remember what
496 * local host:port pair went with that port number.
498 * Hence: in SSH 1 this structure stores host:port pairs we intend
499 * to allow connections to, and is indexed by those host:port
500 * pairs. In SSH 2 it stores a mapping from source port to
501 * destination host:port pair, and is indexed by source port.
503 struct ssh_rportfwd
{
504 unsigned sport
, dport
;
517 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
518 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
519 static void ssh_size(void *handle
, int width
, int height
);
520 static void ssh_special(void *handle
, Telnet_Special
);
521 static int ssh2_try_send(struct ssh_channel
*c
);
522 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
523 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
524 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
525 static int ssh_sendbuffer(void *handle
);
526 static void ssh_do_close(Ssh ssh
);
527 static unsigned long ssh_pkt_getuint32(Ssh ssh
);
528 static int ssh2_pkt_getbool(Ssh ssh
);
529 static void ssh_pkt_getstring(Ssh ssh
, char **p
, int *length
);
531 struct rdpkt1_state_tag
{
532 long len
, pad
, biglen
, to_read
;
533 unsigned long realcrc
, gotcrc
;
539 struct rdpkt2_state_tag
{
540 long len
, pad
, payload
, packetlen
, maclen
;
543 unsigned long incoming_sequence
;
547 const struct plug_function_table
*fn
;
548 /* the above field _must_ be first in the structure */
550 SHA_State exhash
, exhashbase
;
557 unsigned char session_key
[32];
559 int v1_remote_protoflags
;
560 int v1_local_protoflags
;
561 int agentfwd_enabled
;
564 const struct ssh_cipher
*cipher
;
567 const struct ssh2_cipher
*cscipher
, *sccipher
;
568 void *cs_cipher_ctx
, *sc_cipher_ctx
;
569 const struct ssh_mac
*csmac
, *scmac
;
570 void *cs_mac_ctx
, *sc_mac_ctx
;
571 const struct ssh_compress
*cscomp
, *sccomp
;
572 void *cs_comp_ctx
, *sc_comp_ctx
;
573 const struct ssh_kex
*kex
;
574 const struct ssh_signkey
*hostkey
;
575 unsigned char v2_session_id
[20];
581 int echoing
, editing
;
585 int ospeed
, ispeed
; /* temporaries */
586 int term_width
, term_height
;
588 tree234
*channels
; /* indexed by local id */
589 struct ssh_channel
*mainchan
; /* primary session channel */
596 SSH_STATE_BEFORE_SIZE
,
602 int size_needed
, eof_needed
;
605 struct Packet pktout
;
606 unsigned char *deferred_send_data
;
607 int deferred_len
, deferred_size
;
610 * State associated with packet logging
614 struct logblank_t
*pktout_blanks
;
617 * Gross hack: pscp will try to start SFTP but fall back to
618 * scp1 if that fails. This variable is the means by which
619 * scp.c can reach into the SSH code and find out which one it
625 * Used for username and password input.
627 char *userpass_input_buffer
;
628 int userpass_input_buflen
;
629 int userpass_input_bufpos
;
630 int userpass_input_echo
;
632 char *portfwd_strptr
;
638 int v1_throttle_count
;
641 int v1_stdout_throttling
;
642 int v2_outgoing_sequence
;
644 int ssh1_rdpkt_crstate
;
645 int ssh2_rdpkt_crstate
;
646 int do_ssh_init_crstate
;
647 int ssh_gotdata_crstate
;
648 int ssh1_protocol_crstate
;
649 int do_ssh1_login_crstate
;
650 int do_ssh2_transport_crstate
;
651 int do_ssh2_authconn_crstate
;
653 void *do_ssh_init_state
;
654 void *do_ssh1_login_state
;
655 void *do_ssh2_transport_state
;
656 void *do_ssh2_authconn_state
;
658 struct rdpkt1_state_tag rdpkt1_state
;
659 struct rdpkt2_state_tag rdpkt2_state
;
661 void (*protocol
) (Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
662 int (*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
665 * We maintain a full _copy_ of a Config structure here, not
666 * merely a pointer to it. That way, when we're passed a new
667 * one for reconfiguration, we can check the differences and
668 * potentially reconfigure port forwardings etc in mid-session.
673 * Used to transfer data back from async agent callbacks.
675 void *agent_response
;
676 int agent_response_len
;
679 #define logevent(s) logevent(ssh->frontend, s)
681 /* logevent, only printf-formatted. */
682 static void logeventf(Ssh ssh
, const char *fmt
, ...)
688 buf
= dupvprintf(fmt
, ap
);
694 #define bombout(msg) \
696 char *text = dupprintf msg; \
699 connection_fatal(ssh->frontend, "%s", text); \
703 /* Functions to leave bits out of the SSH packet log file. */
705 static void dont_log_password(Ssh ssh
, int blanktype
)
707 if (ssh
->cfg
.logomitpass
)
708 ssh
->pktout_logmode
= blanktype
;
711 static void dont_log_data(Ssh ssh
, int blanktype
)
713 if (ssh
->cfg
.logomitdata
)
714 ssh
->pktout_logmode
= blanktype
;
717 static void end_log_omission(Ssh ssh
)
719 ssh
->pktout_logmode
= PKTLOG_EMIT
;
722 static int ssh_channelcmp(void *av
, void *bv
)
724 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
725 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
726 if (a
->localid
< b
->localid
)
728 if (a
->localid
> b
->localid
)
732 static int ssh_channelfind(void *av
, void *bv
)
734 unsigned *a
= (unsigned *) av
;
735 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
743 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
745 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
746 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
748 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
749 return i
< 0 ?
-1 : +1;
750 if (a
->dport
> b
->dport
)
752 if (a
->dport
< b
->dport
)
757 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
759 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
760 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
762 if (a
->sport
> b
->sport
)
764 if (a
->sport
< b
->sport
)
769 static int alloc_channel_id(Ssh ssh
)
771 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
772 unsigned low
, high
, mid
;
774 struct ssh_channel
*c
;
777 * First-fit allocation of channel numbers: always pick the
778 * lowest unused one. To do this, binary-search using the
779 * counted B-tree to find the largest channel ID which is in a
780 * contiguous sequence from the beginning. (Precisely
781 * everything in that sequence must have ID equal to its tree
782 * index plus CHANNEL_NUMBER_OFFSET.)
784 tsize
= count234(ssh
->channels
);
788 while (high
- low
> 1) {
789 mid
= (high
+ low
) / 2;
790 c
= index234(ssh
->channels
, mid
);
791 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
792 low
= mid
; /* this one is fine */
794 high
= mid
; /* this one is past it */
797 * Now low points to either -1, or the tree index of the
798 * largest ID in the initial sequence.
801 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
802 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
804 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
807 static void c_write(Ssh ssh
, const char *buf
, int len
)
809 if ((flags
& FLAG_STDERR
)) {
811 for (i
= 0; i
< len
; i
++)
813 fputc(buf
[i
], stderr
);
816 from_backend(ssh
->frontend
, 1, buf
, len
);
819 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
822 for (i
= 0; i
< len
; i
++) {
824 c_write(ssh
, "\r\n", 2);
825 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
826 c_write(ssh
, buf
+ i
, 1);
830 static void c_write_str(Ssh ssh
, const char *buf
)
832 c_write(ssh
, buf
, strlen(buf
));
836 * Collect incoming data in the incoming packet buffer.
837 * Decipher and verify the packet when it is completely read.
838 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
839 * Update the *data and *datalen variables.
840 * Return the additional nr of bytes needed, or 0 when
841 * a complete packet is available.
843 static int ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
845 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
847 crBegin(ssh
->ssh1_rdpkt_crstate
);
852 ssh
->pktin
.length
= 0;
854 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
855 while ((*datalen
) == 0)
857 st
->len
= (st
->len
<< 8) + **data
;
858 (*data
)++, (*datalen
)--;
861 st
->pad
= 8 - (st
->len
% 8);
862 st
->biglen
= st
->len
+ st
->pad
;
863 ssh
->pktin
.length
= st
->len
- 5;
865 if (st
->biglen
< 0) {
866 bombout(("Extremely large packet length from server suggests"
867 " data stream corruption"));
871 if (ssh
->pktin
.maxlen
< st
->biglen
) {
872 ssh
->pktin
.maxlen
= st
->biglen
;
873 ssh
->pktin
.data
= sresize(ssh
->pktin
.data
, st
->biglen
+ APIEXTRA
,
877 st
->to_read
= st
->biglen
;
878 st
->p
= ssh
->pktin
.data
;
879 while (st
->to_read
> 0) {
880 st
->chunk
= st
->to_read
;
881 while ((*datalen
) == 0)
882 crReturn(st
->to_read
);
883 if (st
->chunk
> (*datalen
))
884 st
->chunk
= (*datalen
);
885 memcpy(st
->p
, *data
, st
->chunk
);
887 *datalen
-= st
->chunk
;
889 st
->to_read
-= st
->chunk
;
892 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, ssh
->pktin
.data
,
894 bombout(("Network attack (CRC compensation) detected!"));
899 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, ssh
->pktin
.data
, st
->biglen
);
901 st
->realcrc
= crc32_compute(ssh
->pktin
.data
, st
->biglen
- 4);
902 st
->gotcrc
= GET_32BIT(ssh
->pktin
.data
+ st
->biglen
- 4);
903 if (st
->gotcrc
!= st
->realcrc
) {
904 bombout(("Incorrect CRC received on packet"));
908 ssh
->pktin
.body
= ssh
->pktin
.data
+ st
->pad
+ 1;
909 ssh
->pktin
.savedpos
= 0;
911 if (ssh
->v1_compressing
) {
912 unsigned char *decompblk
;
914 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
915 ssh
->pktin
.body
- 1, ssh
->pktin
.length
+ 1,
916 &decompblk
, &decomplen
)) {
917 bombout(("Zlib decompression encountered invalid data"));
921 if (ssh
->pktin
.maxlen
< st
->pad
+ decomplen
) {
922 ssh
->pktin
.maxlen
= st
->pad
+ decomplen
;
923 ssh
->pktin
.data
= sresize(ssh
->pktin
.data
,
924 ssh
->pktin
.maxlen
+ APIEXTRA
,
926 ssh
->pktin
.body
= ssh
->pktin
.data
+ st
->pad
+ 1;
929 memcpy(ssh
->pktin
.body
- 1, decompblk
, decomplen
);
931 ssh
->pktin
.length
= decomplen
- 1;
934 ssh
->pktin
.type
= ssh
->pktin
.body
[-1];
937 * Log incoming packet, possibly omitting sensitive fields.
941 struct logblank_t blank
;
942 if (ssh
->cfg
.logomitdata
) {
943 int do_blank
= FALSE
, blank_prefix
= 0;
944 /* "Session data" packets - omit the data field */
945 if ((ssh
->pktin
.type
== SSH1_SMSG_STDOUT_DATA
) ||
946 (ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
)) {
947 do_blank
= TRUE
; blank_prefix
= 0;
948 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
949 do_blank
= TRUE
; blank_prefix
= 4;
952 blank
.offset
= blank_prefix
;
953 blank
.len
= ssh
->pktin
.length
;
954 blank
.type
= PKTLOG_OMIT
;
958 log_packet(ssh
->logctx
,
959 PKT_INCOMING
, ssh
->pktin
.type
,
960 ssh1_pkt_type(ssh
->pktin
.type
),
961 ssh
->pktin
.body
, ssh
->pktin
.length
,
965 if (ssh
->pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
966 ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
||
967 ssh
->pktin
.type
== SSH1_MSG_DEBUG
||
968 ssh
->pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
969 ssh
->pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
970 long stringlen
= GET_32BIT(ssh
->pktin
.body
);
971 if (stringlen
+ 4 != ssh
->pktin
.length
) {
972 bombout(("Received data packet with bogus string length"));
977 if (ssh
->pktin
.type
== SSH1_MSG_DEBUG
) {
981 ssh_pkt_getstring(ssh
, &msg
, &msglen
);
982 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
987 } else if (ssh
->pktin
.type
== SSH1_MSG_IGNORE
) {
992 if (ssh
->pktin
.type
== SSH1_MSG_DISCONNECT
) {
993 /* log reason code in disconnect message */
997 ssh_pkt_getstring(ssh
, &msg
, &msglen
);
999 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen
, msg
));
1006 static int ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1008 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1010 crBegin(ssh
->ssh2_rdpkt_crstate
);
1013 ssh
->pktin
.type
= 0;
1014 ssh
->pktin
.length
= 0;
1016 st
->cipherblk
= ssh
->sccipher
->blksize
;
1019 if (st
->cipherblk
< 8)
1022 if (ssh
->pktin
.maxlen
< st
->cipherblk
) {
1023 ssh
->pktin
.maxlen
= st
->cipherblk
;
1024 ssh
->pktin
.data
= sresize(ssh
->pktin
.data
, st
->cipherblk
+ APIEXTRA
,
1029 * Acquire and decrypt the first block of the packet. This will
1030 * contain the length and padding details.
1032 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1033 while ((*datalen
) == 0)
1034 crReturn(st
->cipherblk
- st
->i
);
1035 ssh
->pktin
.data
[st
->i
] = *(*data
)++;
1040 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1041 ssh
->pktin
.data
, st
->cipherblk
);
1044 * Now get the length and padding figures.
1046 st
->len
= GET_32BIT(ssh
->pktin
.data
);
1047 st
->pad
= ssh
->pktin
.data
[4];
1050 * _Completely_ silly lengths should be stomped on before they
1051 * do us any more damage.
1053 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
1054 bombout(("Incoming packet was garbled on decryption"));
1059 * This enables us to deduce the payload length.
1061 st
->payload
= st
->len
- st
->pad
- 1;
1063 ssh
->pktin
.length
= st
->payload
+ 5;
1066 * So now we can work out the total packet length.
1068 st
->packetlen
= st
->len
+ 4;
1069 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1072 * Adjust memory allocation if packet is too big.
1074 if (ssh
->pktin
.maxlen
< st
->packetlen
+ st
->maclen
) {
1075 ssh
->pktin
.maxlen
= st
->packetlen
+ st
->maclen
;
1076 ssh
->pktin
.data
= sresize(ssh
->pktin
.data
,
1077 ssh
->pktin
.maxlen
+ APIEXTRA
,
1082 * Read and decrypt the remainder of the packet.
1084 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1086 while ((*datalen
) == 0)
1087 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
1088 ssh
->pktin
.data
[st
->i
] = *(*data
)++;
1091 /* Decrypt everything _except_ the MAC. */
1093 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1094 ssh
->pktin
.data
+ st
->cipherblk
,
1095 st
->packetlen
- st
->cipherblk
);
1101 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, ssh
->pktin
.data
, st
->len
+ 4,
1102 st
->incoming_sequence
)) {
1103 bombout(("Incorrect MAC received on packet"));
1106 st
->incoming_sequence
++; /* whether or not we MACed */
1109 * Decompress packet payload.
1112 unsigned char *newpayload
;
1115 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1116 ssh
->pktin
.data
+ 5, ssh
->pktin
.length
- 5,
1117 &newpayload
, &newlen
)) {
1118 if (ssh
->pktin
.maxlen
< newlen
+ 5) {
1119 ssh
->pktin
.maxlen
= newlen
+ 5;
1120 ssh
->pktin
.data
= sresize(ssh
->pktin
.data
,
1121 ssh
->pktin
.maxlen
+ APIEXTRA
,
1124 ssh
->pktin
.length
= 5 + newlen
;
1125 memcpy(ssh
->pktin
.data
+ 5, newpayload
, newlen
);
1130 ssh
->pktin
.savedpos
= 6;
1131 ssh
->pktin
.body
= ssh
->pktin
.data
;
1132 ssh
->pktin
.type
= ssh
->pktin
.data
[5];
1135 * Log incoming packet, possibly omitting sensitive fields.
1139 struct logblank_t blank
;
1140 if (ssh
->cfg
.logomitdata
) {
1141 int do_blank
= FALSE
, blank_prefix
= 0;
1142 /* "Session data" packets - omit the data field */
1143 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_DATA
) {
1144 do_blank
= TRUE
; blank_prefix
= 4;
1145 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1146 do_blank
= TRUE
; blank_prefix
= 8;
1149 blank
.offset
= blank_prefix
;
1150 blank
.len
= (ssh
->pktin
.length
-6) - blank_prefix
;
1151 blank
.type
= PKTLOG_OMIT
;
1155 log_packet(ssh
->logctx
, PKT_INCOMING
, ssh
->pktin
.type
,
1156 ssh2_pkt_type(ssh
->pkt_ctx
, ssh
->pktin
.type
),
1157 ssh
->pktin
.data
+6, ssh
->pktin
.length
-6,
1161 switch (ssh
->pktin
.type
) {
1163 * These packets we must handle instantly.
1165 case SSH2_MSG_DISCONNECT
:
1167 /* log reason code in disconnect message */
1169 int nowlen
, reason
, msglen
;
1171 reason
= ssh_pkt_getuint32(ssh
);
1172 ssh_pkt_getstring(ssh
, &msg
, &msglen
);
1174 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
1175 buf
= dupprintf("Received disconnect message (%s)",
1176 ssh2_disconnect_reasons
[reason
]);
1178 buf
= dupprintf("Received disconnect message (unknown"
1179 " type %d)", reason
);
1183 buf
= dupprintf("Disconnection message text: %n%.*s",
1184 &nowlen
, msglen
, msg
);
1186 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
1188 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
1189 ssh2_disconnect_reasons
[reason
] : "unknown",
1195 case SSH2_MSG_IGNORE
:
1197 case SSH2_MSG_DEBUG
:
1199 /* log the debug message */
1204 /* XXX maybe we should actually take notice of this */
1205 always_display
= ssh2_pkt_getbool(ssh
);
1206 ssh_pkt_getstring(ssh
, &msg
, &msglen
);
1208 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
1215 * These packets we need do nothing about here.
1217 case SSH2_MSG_UNIMPLEMENTED
:
1218 case SSH2_MSG_SERVICE_REQUEST
:
1219 case SSH2_MSG_SERVICE_ACCEPT
:
1220 case SSH2_MSG_KEXINIT
:
1221 case SSH2_MSG_NEWKEYS
:
1222 case SSH2_MSG_KEXDH_INIT
:
1223 case SSH2_MSG_KEXDH_REPLY
:
1224 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1225 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1226 case SSH2_MSG_KEX_DH_GEX_INIT
:
1227 case SSH2_MSG_KEX_DH_GEX_REPLY
:
1228 case SSH2_MSG_USERAUTH_REQUEST
:
1229 case SSH2_MSG_USERAUTH_FAILURE
:
1230 case SSH2_MSG_USERAUTH_SUCCESS
:
1231 case SSH2_MSG_USERAUTH_BANNER
:
1232 case SSH2_MSG_USERAUTH_PK_OK
:
1233 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1234 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1235 case SSH2_MSG_USERAUTH_INFO_RESPONSE
:
1236 case SSH2_MSG_GLOBAL_REQUEST
:
1237 case SSH2_MSG_REQUEST_SUCCESS
:
1238 case SSH2_MSG_REQUEST_FAILURE
:
1239 case SSH2_MSG_CHANNEL_OPEN
:
1240 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
:
1241 case SSH2_MSG_CHANNEL_OPEN_FAILURE
:
1242 case SSH2_MSG_CHANNEL_WINDOW_ADJUST
:
1243 case SSH2_MSG_CHANNEL_DATA
:
1244 case SSH2_MSG_CHANNEL_EXTENDED_DATA
:
1245 case SSH2_MSG_CHANNEL_EOF
:
1246 case SSH2_MSG_CHANNEL_CLOSE
:
1247 case SSH2_MSG_CHANNEL_REQUEST
:
1248 case SSH2_MSG_CHANNEL_SUCCESS
:
1249 case SSH2_MSG_CHANNEL_FAILURE
:
1253 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1256 ssh2_pkt_init(ssh
, SSH2_MSG_UNIMPLEMENTED
);
1257 ssh2_pkt_adduint32(ssh
, st
->incoming_sequence
- 1);
1265 static void ssh1_pktout_size(Ssh ssh
, int len
)
1269 len
+= 5; /* type and CRC */
1270 pad
= 8 - (len
% 8);
1273 ssh
->pktout
.length
= len
- 5;
1274 if (ssh
->pktout
.maxlen
< biglen
) {
1275 ssh
->pktout
.maxlen
= biglen
;
1277 /* Allocate enough buffer space for extra block
1278 * for MS CryptEncrypt() */
1279 ssh
->pktout
.data
= sresize(ssh
->pktout
.data
, biglen
+ 12,
1282 ssh
->pktout
.data
= sresize(ssh
->pktout
.data
, biglen
+ 4,
1286 ssh
->pktout
.body
= ssh
->pktout
.data
+ 4 + pad
+ 1;
1289 static void s_wrpkt_start(Ssh ssh
, int type
, int len
)
1291 ssh1_pktout_size(ssh
, len
);
1292 ssh
->pktout
.type
= type
;
1293 /* Initialise log omission state */
1294 ssh
->pktout_nblanks
= 0;
1295 ssh
->pktout_blanks
= NULL
;
1298 static int s_wrpkt_prepare(Ssh ssh
)
1304 * XXX various versions of SC (including 8.8.4) screw up the
1305 * register allocation in this function and use the same register
1306 * (D6) for len and as a temporary, with predictable results. The
1307 * following sledgehammer prevents this.
1313 ssh
->pktout
.body
[-1] = ssh
->pktout
.type
;
1316 log_packet(ssh
->logctx
, PKT_OUTGOING
, ssh
->pktout
.type
,
1317 ssh1_pkt_type(ssh
->pktout
.type
),
1318 ssh
->pktout
.body
, ssh
->pktout
.length
,
1319 ssh
->pktout_nblanks
, ssh
->pktout_blanks
);
1320 sfree(ssh
->pktout_blanks
); ssh
->pktout_blanks
= NULL
;
1321 ssh
->pktout_nblanks
= 0;
1323 if (ssh
->v1_compressing
) {
1324 unsigned char *compblk
;
1326 zlib_compress_block(ssh
->cs_comp_ctx
,
1327 ssh
->pktout
.body
- 1, ssh
->pktout
.length
+ 1,
1328 &compblk
, &complen
);
1329 ssh1_pktout_size(ssh
, complen
- 1);
1330 memcpy(ssh
->pktout
.body
- 1, compblk
, complen
);
1334 len
= ssh
->pktout
.length
+ 5; /* type and CRC */
1335 pad
= 8 - (len
% 8);
1338 for (i
= 0; i
< pad
; i
++)
1339 ssh
->pktout
.data
[i
+ 4] = random_byte();
1340 crc
= crc32_compute(ssh
->pktout
.data
+ 4, biglen
- 4);
1341 PUT_32BIT(ssh
->pktout
.data
+ biglen
, crc
);
1342 PUT_32BIT(ssh
->pktout
.data
, len
);
1345 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, ssh
->pktout
.data
+ 4, biglen
);
1350 static void s_wrpkt(Ssh ssh
)
1353 len
= s_wrpkt_prepare(ssh
);
1354 backlog
= sk_write(ssh
->s
, (char *)ssh
->pktout
.data
, len
);
1355 if (backlog
> SSH_MAX_BACKLOG
)
1356 ssh_throttle_all(ssh
, 1, backlog
);
1359 static void s_wrpkt_defer(Ssh ssh
)
1362 len
= s_wrpkt_prepare(ssh
);
1363 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1364 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1365 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1369 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, ssh
->pktout
.data
, len
);
1370 ssh
->deferred_len
+= len
;
1374 * Construct a packet with the specified contents.
1376 static void construct_packet(Ssh ssh
, int pkttype
, va_list ap1
, va_list ap2
)
1378 unsigned char *p
, *argp
, argchar
;
1379 unsigned long argint
;
1380 int pktlen
, argtype
, arglen
;
1384 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1387 (void) va_arg(ap1
, int);
1391 (void) va_arg(ap1
, int);
1395 (void) va_arg(ap1
, unsigned char *);
1396 arglen
= va_arg(ap1
, int);
1400 argp
= va_arg(ap1
, unsigned char *);
1401 arglen
= strlen((char *)argp
);
1402 pktlen
+= 4 + arglen
;
1405 bn
= va_arg(ap1
, Bignum
);
1406 pktlen
+= ssh1_bignum_length(bn
);
1411 /* ignore this pass */
1418 s_wrpkt_start(ssh
, pkttype
, pktlen
);
1419 p
= ssh
->pktout
.body
;
1421 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1422 int offset
= p
- ssh
->pktout
.body
, len
= 0;
1424 /* Actual fields in the packet */
1426 argint
= va_arg(ap2
, int);
1427 PUT_32BIT(p
, argint
);
1431 argchar
= (unsigned char) va_arg(ap2
, int);
1436 argp
= va_arg(ap2
, unsigned char *);
1437 arglen
= va_arg(ap2
, int);
1438 memcpy(p
, argp
, arglen
);
1442 argp
= va_arg(ap2
, unsigned char *);
1443 arglen
= strlen((char *)argp
);
1444 PUT_32BIT(p
, arglen
);
1445 memcpy(p
+ 4, argp
, arglen
);
1449 bn
= va_arg(ap2
, Bignum
);
1450 len
= ssh1_write_bignum(p
, bn
);
1452 /* Tokens for modifications to packet logging */
1454 dont_log_password(ssh
, PKTLOG_BLANK
);
1457 dont_log_data(ssh
, PKTLOG_OMIT
);
1460 end_log_omission(ssh
);
1464 /* Deal with logfile omission, if required. */
1465 if (len
&& (ssh
->pktout_logmode
!= PKTLOG_EMIT
)) {
1466 ssh
->pktout_nblanks
++;
1467 ssh
->pktout_blanks
= sresize(ssh
->pktout_blanks
,
1468 ssh
->pktout_nblanks
,
1470 ssh
->pktout_blanks
[ssh
->pktout_nblanks
-1].offset
= offset
;
1471 ssh
->pktout_blanks
[ssh
->pktout_nblanks
-1].len
= len
;
1472 ssh
->pktout_blanks
[ssh
->pktout_nblanks
-1].type
=
1473 ssh
->pktout_logmode
;
1478 static void send_packet(Ssh ssh
, int pkttype
, ...)
1481 va_start(ap1
, pkttype
);
1482 va_start(ap2
, pkttype
);
1483 construct_packet(ssh
, pkttype
, ap1
, ap2
);
1487 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1490 va_start(ap1
, pkttype
);
1491 va_start(ap2
, pkttype
);
1492 construct_packet(ssh
, pkttype
, ap1
, ap2
);
1496 static int ssh_versioncmp(char *a
, char *b
)
1499 unsigned long av
, bv
;
1501 av
= strtoul(a
, &ae
, 10);
1502 bv
= strtoul(b
, &be
, 10);
1504 return (av
< bv ?
-1 : +1);
1509 av
= strtoul(ae
, &ae
, 10);
1510 bv
= strtoul(be
, &be
, 10);
1512 return (av
< bv ?
-1 : +1);
1517 * Utility routines for putting an SSH-protocol `string' and
1518 * `uint32' into a SHA state.
1521 static void sha_string(SHA_State
* s
, void *str
, int len
)
1523 unsigned char lenblk
[4];
1524 PUT_32BIT(lenblk
, len
);
1525 SHA_Bytes(s
, lenblk
, 4);
1526 SHA_Bytes(s
, str
, len
);
1529 static void sha_uint32(SHA_State
* s
, unsigned i
)
1531 unsigned char intblk
[4];
1532 PUT_32BIT(intblk
, i
);
1533 SHA_Bytes(s
, intblk
, 4);
1537 * SSH2 packet construction functions.
1539 static void ssh2_pkt_ensure(Ssh ssh
, int length
)
1541 if (ssh
->pktout
.maxlen
< length
) {
1542 ssh
->pktout
.maxlen
= length
+ 256;
1543 ssh
->pktout
.data
= sresize(ssh
->pktout
.data
,
1544 ssh
->pktout
.maxlen
+ APIEXTRA
,
1546 if (!ssh
->pktout
.data
)
1547 fatalbox("Out of memory");
1550 static void ssh2_pkt_adddata(Ssh ssh
, void *data
, int len
)
1552 if (ssh
->pktout_logmode
!= PKTLOG_EMIT
) {
1553 ssh
->pktout_nblanks
++;
1554 ssh
->pktout_blanks
= sresize(ssh
->pktout_blanks
, ssh
->pktout_nblanks
,
1556 ssh
->pktout_blanks
[ssh
->pktout_nblanks
-1].offset
=
1557 ssh
->pktout
.length
- 6;
1558 ssh
->pktout_blanks
[ssh
->pktout_nblanks
-1].len
= len
;
1559 ssh
->pktout_blanks
[ssh
->pktout_nblanks
-1].type
= ssh
->pktout_logmode
;
1561 ssh
->pktout
.length
+= len
;
1562 ssh2_pkt_ensure(ssh
, ssh
->pktout
.length
);
1563 memcpy(ssh
->pktout
.data
+ ssh
->pktout
.length
- len
, data
, len
);
1565 static void ssh2_pkt_addbyte(Ssh ssh
, unsigned char byte
)
1567 ssh2_pkt_adddata(ssh
, &byte
, 1);
1569 static void ssh2_pkt_init(Ssh ssh
, int pkt_type
)
1571 ssh
->pktout
.length
= 5;
1572 ssh
->pktout_nblanks
= 0; ssh
->pktout_blanks
= NULL
;
1573 ssh2_pkt_addbyte(ssh
, (unsigned char) pkt_type
);
1575 static void ssh2_pkt_addbool(Ssh ssh
, unsigned char value
)
1577 ssh2_pkt_adddata(ssh
, &value
, 1);
1579 static void ssh2_pkt_adduint32(Ssh ssh
, unsigned long value
)
1582 PUT_32BIT(x
, value
);
1583 ssh2_pkt_adddata(ssh
, x
, 4);
1585 static void ssh2_pkt_addstring_start(Ssh ssh
)
1587 ssh2_pkt_adduint32(ssh
, 0);
1588 ssh
->pktout
.savedpos
= ssh
->pktout
.length
;
1590 static void ssh2_pkt_addstring_str(Ssh ssh
, char *data
)
1592 ssh2_pkt_adddata(ssh
, data
, strlen(data
));
1593 PUT_32BIT(ssh
->pktout
.data
+ ssh
->pktout
.savedpos
- 4,
1594 ssh
->pktout
.length
- ssh
->pktout
.savedpos
);
1596 static void ssh2_pkt_addstring_data(Ssh ssh
, char *data
, int len
)
1598 ssh2_pkt_adddata(ssh
, data
, len
);
1599 PUT_32BIT(ssh
->pktout
.data
+ ssh
->pktout
.savedpos
- 4,
1600 ssh
->pktout
.length
- ssh
->pktout
.savedpos
);
1602 static void ssh2_pkt_addstring(Ssh ssh
, char *data
)
1604 ssh2_pkt_addstring_start(ssh
);
1605 ssh2_pkt_addstring_str(ssh
, data
);
1607 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1610 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1611 p
= snewn(n
+ 1, unsigned char);
1613 fatalbox("out of memory");
1615 for (i
= 1; i
<= n
; i
++)
1616 p
[i
] = bignum_byte(b
, n
- i
);
1618 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1620 memmove(p
, p
+ i
, n
+ 1 - i
);
1624 static void ssh2_pkt_addmp(Ssh ssh
, Bignum b
)
1628 p
= ssh2_mpint_fmt(b
, &len
);
1629 ssh2_pkt_addstring_start(ssh
);
1630 ssh2_pkt_addstring_data(ssh
, (char *)p
, len
);
1635 * Construct an SSH2 final-form packet: compress it, encrypt it,
1636 * put the MAC on it. Final packet, ready to be sent, is stored in
1637 * ssh->pktout.data. Total length is returned.
1639 static int ssh2_pkt_construct(Ssh ssh
)
1641 int cipherblk
, maclen
, padding
, i
;
1644 log_packet(ssh
->logctx
, PKT_OUTGOING
, ssh
->pktout
.data
[5],
1645 ssh2_pkt_type(ssh
->pkt_ctx
, ssh
->pktout
.data
[5]),
1646 ssh
->pktout
.data
+ 6, ssh
->pktout
.length
- 6,
1647 ssh
->pktout_nblanks
, ssh
->pktout_blanks
);
1648 sfree(ssh
->pktout_blanks
); ssh
->pktout_blanks
= NULL
;
1649 ssh
->pktout_nblanks
= 0;
1652 * Compress packet payload.
1655 unsigned char *newpayload
;
1658 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, ssh
->pktout
.data
+ 5,
1659 ssh
->pktout
.length
- 5,
1660 &newpayload
, &newlen
)) {
1661 ssh
->pktout
.length
= 5;
1662 ssh2_pkt_adddata(ssh
, newpayload
, newlen
);
1668 * Add padding. At least four bytes, and must also bring total
1669 * length (minus MAC) up to a multiple of the block size.
1671 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1672 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1675 (cipherblk
- (ssh
->pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
1676 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1677 ssh2_pkt_ensure(ssh
, ssh
->pktout
.length
+ padding
+ maclen
);
1678 ssh
->pktout
.data
[4] = padding
;
1679 for (i
= 0; i
< padding
; i
++)
1680 ssh
->pktout
.data
[ssh
->pktout
.length
+ i
] = random_byte();
1681 PUT_32BIT(ssh
->pktout
.data
, ssh
->pktout
.length
+ padding
- 4);
1683 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, ssh
->pktout
.data
,
1684 ssh
->pktout
.length
+ padding
,
1685 ssh
->v2_outgoing_sequence
);
1686 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1689 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1690 ssh
->pktout
.data
, ssh
->pktout
.length
+ padding
);
1692 /* Ready-to-send packet starts at ssh->pktout.data. We return length. */
1693 return ssh
->pktout
.length
+ padding
+ maclen
;
1697 * Construct and send an SSH2 packet immediately.
1699 static void ssh2_pkt_send(Ssh ssh
)
1703 len
= ssh2_pkt_construct(ssh
);
1704 backlog
= sk_write(ssh
->s
, (char *)ssh
->pktout
.data
, len
);
1705 if (backlog
> SSH_MAX_BACKLOG
)
1706 ssh_throttle_all(ssh
, 1, backlog
);
1710 * Construct an SSH2 packet and add it to a deferred data block.
1711 * Useful for sending multiple packets in a single sk_write() call,
1712 * to prevent a traffic-analysing listener from being able to work
1713 * out the length of any particular packet (such as the password
1716 * Note that because SSH2 sequence-numbers its packets, this can
1717 * NOT be used as an m4-style `defer' allowing packets to be
1718 * constructed in one order and sent in another.
1720 static void ssh2_pkt_defer(Ssh ssh
)
1722 int len
= ssh2_pkt_construct(ssh
);
1723 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1724 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1725 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1729 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, ssh
->pktout
.data
, len
);
1730 ssh
->deferred_len
+= len
;
1734 * Send the whole deferred data block constructed by
1735 * ssh2_pkt_defer() or SSH1's defer_packet().
1737 static void ssh_pkt_defersend(Ssh ssh
)
1740 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1742 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1743 sfree(ssh
->deferred_send_data
);
1744 ssh
->deferred_send_data
= NULL
;
1745 if (backlog
> SSH_MAX_BACKLOG
)
1746 ssh_throttle_all(ssh
, 1, backlog
);
1750 void bndebug(char *string
, Bignum b
)
1754 p
= ssh2_mpint_fmt(b
, &len
);
1755 debug(("%s", string
));
1756 for (i
= 0; i
< len
; i
++)
1757 debug((" %02x", p
[i
]));
1763 static void sha_mpint(SHA_State
* s
, Bignum b
)
1767 p
= ssh2_mpint_fmt(b
, &len
);
1768 sha_string(s
, p
, len
);
1773 * Packet decode functions for both SSH1 and SSH2.
1775 static unsigned long ssh_pkt_getuint32(Ssh ssh
)
1777 unsigned long value
;
1778 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< 4)
1779 return 0; /* arrgh, no way to decline (FIXME?) */
1780 value
= GET_32BIT(ssh
->pktin
.body
+ ssh
->pktin
.savedpos
);
1781 ssh
->pktin
.savedpos
+= 4;
1784 static int ssh2_pkt_getbool(Ssh ssh
)
1786 unsigned long value
;
1787 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< 1)
1788 return 0; /* arrgh, no way to decline (FIXME?) */
1789 value
= ssh
->pktin
.body
[ssh
->pktin
.savedpos
] != 0;
1790 ssh
->pktin
.savedpos
++;
1793 static void ssh_pkt_getstring(Ssh ssh
, char **p
, int *length
)
1798 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< 4)
1800 len
= GET_32BIT(ssh
->pktin
.body
+ ssh
->pktin
.savedpos
);
1804 ssh
->pktin
.savedpos
+= 4;
1805 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< *length
)
1807 *p
= (char *)(ssh
->pktin
.body
+ ssh
->pktin
.savedpos
);
1808 ssh
->pktin
.savedpos
+= *length
;
1810 static void *ssh_pkt_getdata(Ssh ssh
, int length
)
1812 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< length
)
1814 ssh
->pktin
.savedpos
+= length
;
1815 return ssh
->pktin
.body
+ (ssh
->pktin
.savedpos
- length
);
1817 static int ssh1_pkt_getrsakey(Ssh ssh
, struct RSAKey
*key
,
1818 unsigned char **keystr
)
1822 j
= makekey(ssh
->pktin
.body
+ ssh
->pktin
.savedpos
,
1823 ssh
->pktin
.length
- ssh
->pktin
.savedpos
,
1829 ssh
->pktin
.savedpos
+= j
;
1830 assert(ssh
->pktin
.savedpos
< ssh
->pktin
.length
);
1834 static Bignum
ssh1_pkt_getmp(Ssh ssh
)
1839 j
= ssh1_read_bignum(ssh
->pktin
.body
+ ssh
->pktin
.savedpos
,
1840 ssh
->pktin
.length
- ssh
->pktin
.savedpos
, &b
);
1845 ssh
->pktin
.savedpos
+= j
;
1848 static Bignum
ssh2_pkt_getmp(Ssh ssh
)
1854 ssh_pkt_getstring(ssh
, &p
, &length
);
1858 bombout(("internal error: Can't handle negative mpints"));
1861 b
= bignum_from_bytes((unsigned char *)p
, length
);
1866 * Helper function to add an SSH2 signature blob to a packet.
1867 * Expects to be shown the public key blob as well as the signature
1868 * blob. Normally works just like ssh2_pkt_addstring, but will
1869 * fiddle with the signature packet if necessary for
1870 * BUG_SSH2_RSA_PADDING.
1872 static void ssh2_add_sigblob(Ssh ssh
, void *pkblob_v
, int pkblob_len
,
1873 void *sigblob_v
, int sigblob_len
)
1875 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1876 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1878 /* dmemdump(pkblob, pkblob_len); */
1879 /* dmemdump(sigblob, sigblob_len); */
1882 * See if this is in fact an ssh-rsa signature and a buggy
1883 * server; otherwise we can just do this the easy way.
1885 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1886 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1887 int pos
, len
, siglen
;
1890 * Find the byte length of the modulus.
1893 pos
= 4+7; /* skip over "ssh-rsa" */
1894 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1895 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
1896 pos
+= 4; /* find modulus itself */
1897 while (len
> 0 && pkblob
[pos
] == 0)
1899 /* debug(("modulus length is %d\n", len)); */
1902 * Now find the signature integer.
1904 pos
= 4+7; /* skip over "ssh-rsa" */
1905 siglen
= GET_32BIT(sigblob
+pos
);
1906 /* debug(("signature length is %d\n", siglen)); */
1908 if (len
!= siglen
) {
1909 unsigned char newlen
[4];
1910 ssh2_pkt_addstring_start(ssh
);
1911 ssh2_pkt_addstring_data(ssh
, (char *)sigblob
, pos
);
1912 /* dmemdump(sigblob, pos); */
1913 pos
+= 4; /* point to start of actual sig */
1914 PUT_32BIT(newlen
, len
);
1915 ssh2_pkt_addstring_data(ssh
, (char *)newlen
, 4);
1916 /* dmemdump(newlen, 4); */
1918 while (len
-- > siglen
) {
1919 ssh2_pkt_addstring_data(ssh
, (char *)newlen
, 1);
1920 /* dmemdump(newlen, 1); */
1922 ssh2_pkt_addstring_data(ssh
, (char *)(sigblob
+pos
), siglen
);
1923 /* dmemdump(sigblob+pos, siglen); */
1927 /* Otherwise fall through and do it the easy way. */
1930 ssh2_pkt_addstring_start(ssh
);
1931 ssh2_pkt_addstring_data(ssh
, (char *)sigblob
, sigblob_len
);
1935 * Examine the remote side's version string and compare it against
1936 * a list of known buggy implementations.
1938 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
1940 char *imp
; /* pointer to implementation part */
1942 imp
+= strcspn(imp
, "-");
1944 imp
+= strcspn(imp
, "-");
1947 ssh
->remote_bugs
= 0;
1949 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
1950 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
1951 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
1952 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
1953 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
1954 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
1956 * These versions don't support SSH1_MSG_IGNORE, so we have
1957 * to use a different defence against password length
1960 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
1961 logevent("We believe remote version has SSH1 ignore bug");
1964 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
1965 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
1966 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
1968 * These versions need a plain password sent; they can't
1969 * handle having a null and a random length of data after
1972 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
1973 logevent("We believe remote version needs a plain SSH1 password");
1976 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
1977 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
1978 (!strcmp(imp
, "Cisco-1.25")))) {
1980 * These versions apparently have no clue whatever about
1981 * RSA authentication and will panic and die if they see
1982 * an AUTH_RSA message.
1984 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
1985 logevent("We believe remote version can't handle RSA authentication");
1988 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
1989 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
1990 !wc_match("* VShell", imp
) &&
1991 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
1992 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
1993 wc_match("2.1 *", imp
)))) {
1995 * These versions have the HMAC bug.
1997 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
1998 logevent("We believe remote version has SSH2 HMAC bug");
2001 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2002 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2003 !wc_match("* VShell", imp
) &&
2004 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2006 * These versions have the key-derivation bug (failing to
2007 * include the literal shared secret in the hashes that
2008 * generate the keys).
2010 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2011 logevent("We believe remote version has SSH2 key-derivation bug");
2014 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2015 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2016 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2017 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2019 * These versions have the SSH2 RSA padding bug.
2021 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2022 logevent("We believe remote version has SSH2 RSA padding bug");
2025 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2026 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2027 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2029 * These versions have the SSH2 session-ID bug in
2030 * public-key authentication.
2032 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2033 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2036 if (ssh
->cfg
.sshbug_dhgex2
== FORCE_ON
) {
2038 * User specified the SSH2 DH GEX bug.
2040 ssh
->remote_bugs
|= BUG_SSH2_DH_GEX
;
2041 logevent("We believe remote version has SSH2 DH group exchange bug");
2045 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2047 struct do_ssh_init_state
{
2055 crState(do_ssh_init_state
);
2057 crBegin(ssh
->do_ssh_init_crstate
);
2059 /* Search for the string "SSH-" in the input. */
2062 static const int transS
[] = { 1, 2, 2, 1 };
2063 static const int transH
[] = { 0, 0, 3, 0 };
2064 static const int transminus
[] = { 0, 0, 0, -1 };
2066 s
->i
= transS
[s
->i
];
2068 s
->i
= transH
[s
->i
];
2070 s
->i
= transminus
[s
->i
];
2075 crReturn(1); /* get another character */
2079 s
->vstring
= snewn(s
->vstrsize
, char);
2080 strcpy(s
->vstring
, "SSH-");
2084 crReturn(1); /* get another char */
2085 if (s
->vslen
>= s
->vstrsize
- 1) {
2087 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2089 s
->vstring
[s
->vslen
++] = c
;
2092 s
->version
[s
->i
] = '\0';
2094 } else if (s
->i
< sizeof(s
->version
) - 1)
2095 s
->version
[s
->i
++] = c
;
2096 } else if (c
== '\012')
2100 ssh
->agentfwd_enabled
= FALSE
;
2101 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2103 s
->vstring
[s
->vslen
] = 0;
2104 s
->vstring
[strcspn(s
->vstring
, "\r\n")] = '\0';/* remove EOL chars */
2107 vlog
= snewn(20 + s
->vslen
, char);
2108 sprintf(vlog
, "Server version: %s", s
->vstring
);
2112 ssh_detect_bugs(ssh
, s
->vstring
);
2115 * Decide which SSH protocol version to support.
2118 /* Anything strictly below "2.0" means protocol 1 is supported. */
2119 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2120 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2121 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2123 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2124 bombout(("SSH protocol version 1 required by user but not provided by server"));
2127 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2128 bombout(("SSH protocol version 2 required by user but not provided by server"));
2132 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2136 char verstring
[80], vlog
[100];
2137 sprintf(verstring
, "SSH-2.0-%s", sshver
);
2138 SHA_Init(&ssh
->exhashbase
);
2140 * Hash our version string and their version string.
2142 sha_string(&ssh
->exhashbase
, verstring
, strlen(verstring
));
2143 sha_string(&ssh
->exhashbase
, s
->vstring
, strcspn(s
->vstring
, "\r\n"));
2144 sprintf(vlog
, "We claim version: %s", verstring
);
2146 strcat(verstring
, "\012");
2147 logevent("Using SSH protocol version 2");
2148 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2149 ssh
->protocol
= ssh2_protocol
;
2151 ssh
->s_rdpkt
= ssh2_rdpkt
;
2156 char verstring
[80], vlog
[100];
2157 sprintf(verstring
, "SSH-%s-%s",
2158 (ssh_versioncmp(s
->version
, "1.5") <= 0 ? s
->version
: "1.5"),
2160 sprintf(vlog
, "We claim version: %s", verstring
);
2162 strcat(verstring
, "\012");
2164 logevent("Using SSH protocol version 1");
2165 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2166 ssh
->protocol
= ssh1_protocol
;
2168 ssh
->s_rdpkt
= ssh1_rdpkt
;
2170 update_specials_menu(ssh
->frontend
);
2171 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2178 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2180 crBegin(ssh
->ssh_gotdata_crstate
);
2183 * To begin with, feed the characters one by one to the
2184 * protocol initialisation / selection function do_ssh_init().
2185 * When that returns 0, we're done with the initial greeting
2186 * exchange and can move on to packet discipline.
2189 int ret
; /* need not be kept across crReturn */
2191 crReturnV
; /* more data please */
2192 ret
= do_ssh_init(ssh
, *data
);
2200 * We emerge from that loop when the initial negotiation is
2201 * over and we have selected an s_rdpkt function. Now pass
2202 * everything to s_rdpkt, and then pass the resulting packets
2203 * to the proper protocol handler.
2208 while (datalen
> 0) {
2209 if (ssh
->s_rdpkt(ssh
, &data
, &datalen
) == 0) {
2210 if (ssh
->state
== SSH_STATE_CLOSED
) {
2213 ssh
->protocol(ssh
, NULL
, 0, 1);
2214 if (ssh
->state
== SSH_STATE_CLOSED
) {
2224 static void ssh_do_close(Ssh ssh
)
2227 struct ssh_channel
*c
;
2229 ssh
->state
= SSH_STATE_CLOSED
;
2235 * Now we must shut down any port and X forwardings going
2236 * through this connection.
2238 if (ssh
->channels
) {
2239 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2242 x11_close(c
->u
.x11
.s
);
2245 pfd_close(c
->u
.pfd
.s
);
2248 del234(ssh
->channels
, c
);
2249 if (ssh
->version
== 2)
2250 bufchain_clear(&c
->v
.v2
.outbuffer
);
2256 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2259 Ssh ssh
= (Ssh
) plug
;
2262 /* A socket error has occurred. */
2263 logevent(error_msg
);
2264 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2266 /* Otherwise, the remote side closed the connection normally. */
2271 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2273 Ssh ssh
= (Ssh
) plug
;
2274 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2275 if (ssh
->state
== SSH_STATE_CLOSED
) {
2282 static void ssh_sent(Plug plug
, int bufsize
)
2284 Ssh ssh
= (Ssh
) plug
;
2286 * If the send backlog on the SSH socket itself clears, we
2287 * should unthrottle the whole world if it was throttled.
2289 if (bufsize
< SSH_MAX_BACKLOG
)
2290 ssh_throttle_all(ssh
, 0, bufsize
);
2294 * Connect to specified host and port.
2295 * Returns an error message, or NULL on success.
2296 * Also places the canonical host name into `realhost'. It must be
2297 * freed by the caller.
2299 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2300 char **realhost
, int nodelay
, int keepalive
)
2302 static const struct plug_function_table fn_table
= {
2312 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2313 if (!ssh
->savedhost
)
2314 fatalbox("Out of memory");
2315 strcpy(ssh
->savedhost
, host
);
2318 port
= 22; /* default ssh port */
2319 ssh
->savedport
= port
;
2324 logeventf(ssh
, "Looking up host \"%s\"", host
);
2325 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
);
2326 if ((err
= sk_addr_error(addr
)) != NULL
) {
2336 sk_getaddr(addr
, addrbuf
, 100);
2337 logeventf(ssh
, "Connecting to %s port %d", addrbuf
, port
);
2339 ssh
->fn
= &fn_table
;
2340 ssh
->s
= new_connection(addr
, *realhost
, port
,
2341 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2342 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2351 * Throttle or unthrottle the SSH connection.
2353 static void ssh1_throttle(Ssh ssh
, int adjust
)
2355 int old_count
= ssh
->v1_throttle_count
;
2356 ssh
->v1_throttle_count
+= adjust
;
2357 assert(ssh
->v1_throttle_count
>= 0);
2358 if (ssh
->v1_throttle_count
&& !old_count
) {
2359 sk_set_frozen(ssh
->s
, 1);
2360 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2361 sk_set_frozen(ssh
->s
, 0);
2366 * Throttle or unthrottle _all_ local data streams (for when sends
2367 * on the SSH connection itself back up).
2369 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2372 struct ssh_channel
*c
;
2374 if (enable
== ssh
->throttled_all
)
2376 ssh
->throttled_all
= enable
;
2377 ssh
->overall_bufsize
= bufsize
;
2380 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2382 case CHAN_MAINSESSION
:
2384 * This is treated separately, outside the switch.
2388 x11_override_throttle(c
->u
.x11
.s
, enable
);
2391 /* Agent channels require no buffer management. */
2394 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2401 * Username and password input, abstracted off into routines
2402 * reusable in several places - even between SSH1 and SSH2.
2405 /* Set up a username or password input loop on a given buffer. */
2406 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2408 ssh
->userpass_input_buffer
= buffer
;
2409 ssh
->userpass_input_buflen
= buflen
;
2410 ssh
->userpass_input_bufpos
= 0;
2411 ssh
->userpass_input_echo
= echo
;
2415 * Process some terminal data in the course of username/password
2416 * input. Returns >0 for success (line of input returned in
2417 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2418 * for inconclusive (keep waiting for more input please).
2420 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2425 switch (c
= *in
++) {
2428 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2429 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2434 if (ssh
->userpass_input_bufpos
> 0) {
2435 if (ssh
->userpass_input_echo
)
2436 c_write_str(ssh
, "\b \b");
2437 ssh
->userpass_input_bufpos
--;
2442 while (ssh
->userpass_input_bufpos
> 0) {
2443 if (ssh
->userpass_input_echo
)
2444 c_write_str(ssh
, "\b \b");
2445 ssh
->userpass_input_bufpos
--;
2454 * This simplistic check for printability is disabled
2455 * when we're doing password input, because some people
2456 * have control characters in their passwords.o
2458 if ((!ssh
->userpass_input_echo
||
2459 (c
>= ' ' && c
<= '~') ||
2460 ((unsigned char) c
>= 160))
2461 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2462 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2463 if (ssh
->userpass_input_echo
)
2464 c_write(ssh
, &c
, 1);
2472 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2474 Ssh ssh
= (Ssh
) sshv
;
2476 ssh
->agent_response
= reply
;
2477 ssh
->agent_response_len
= replylen
;
2479 if (ssh
->version
== 1)
2480 do_ssh1_login(ssh
, NULL
, -1, 0);
2482 do_ssh2_authconn(ssh
, NULL
, -1, 0);
2485 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2487 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2489 void *sentreply
= reply
;
2492 /* Fake SSH_AGENT_FAILURE. */
2493 sentreply
= "\0\0\0\1\5";
2496 if (ssh
->version
== 2) {
2497 ssh2_add_channel_data(c
, sentreply
, replylen
);
2500 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2501 PKT_INT
, c
->remoteid
,
2504 PKT_DATA
, sentreply
, replylen
,
2513 * Handle the key exchange and user authentication phases.
2515 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
2518 unsigned char cookie
[8], *ptr
;
2519 struct RSAKey servkey
, hostkey
;
2520 struct MD5Context md5c
;
2521 struct do_ssh1_login_state
{
2523 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2524 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2525 int tried_publickey
, tried_agent
;
2526 int tis_auth_refused
, ccard_auth_refused
;
2527 unsigned char session_id
[16];
2530 void *publickey_blob
;
2531 int publickey_bloblen
;
2537 unsigned char request
[5], *response
, *p
;
2546 crState(do_ssh1_login_state
);
2548 crBegin(ssh
->do_ssh1_login_crstate
);
2553 if (ssh
->pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
2554 bombout(("Public key packet not received"));
2558 logevent("Received public keys");
2560 ptr
= ssh_pkt_getdata(ssh
, 8);
2562 bombout(("SSH1 public key packet stopped before random cookie"));
2565 memcpy(cookie
, ptr
, 8);
2567 if (!ssh1_pkt_getrsakey(ssh
, &servkey
, &s
->keystr1
) ||
2568 !ssh1_pkt_getrsakey(ssh
, &hostkey
, &s
->keystr2
)) {
2569 bombout(("Failed to read SSH1 public keys from public key packet"));
2574 * Log the host key fingerprint.
2578 logevent("Host key fingerprint is:");
2579 strcpy(logmsg
, " ");
2580 hostkey
.comment
= NULL
;
2581 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2582 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2586 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(ssh
);
2587 s
->supported_ciphers_mask
= ssh_pkt_getuint32(ssh
);
2588 s
->supported_auths_mask
= ssh_pkt_getuint32(ssh
);
2590 ssh
->v1_local_protoflags
=
2591 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2592 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2595 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2596 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2597 MD5Update(&md5c
, cookie
, 8);
2598 MD5Final(s
->session_id
, &md5c
);
2600 for (i
= 0; i
< 32; i
++)
2601 ssh
->session_key
[i
] = random_byte();
2604 * Verify that the `bits' and `bytes' parameters match.
2606 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
2607 servkey
.bits
> servkey
.bytes
* 8) {
2608 bombout(("SSH1 public keys were badly formatted"));
2612 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2614 s
->rsabuf
= snewn(s
->len
, unsigned char);
2616 fatalbox("Out of memory");
2619 * Verify the host key.
2623 * First format the key into a string.
2625 int len
= rsastr_len(&hostkey
);
2626 char fingerprint
[100];
2627 char *keystr
= snewn(len
, char);
2629 fatalbox("Out of memory");
2630 rsastr_fmt(keystr
, &hostkey
);
2631 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2632 verify_ssh_host_key(ssh
->frontend
,
2633 ssh
->savedhost
, ssh
->savedport
, "rsa", keystr
,
2638 for (i
= 0; i
< 32; i
++) {
2639 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2641 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2644 if (hostkey
.bytes
> servkey
.bytes
) {
2645 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
2647 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2649 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2651 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2654 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2658 logevent("Encrypted session key");
2661 int cipher_chosen
= 0, warn
= 0;
2662 char *cipher_string
= NULL
;
2664 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2665 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
2666 if (next_cipher
== CIPHER_WARN
) {
2667 /* If/when we choose a cipher, warn about it */
2669 } else if (next_cipher
== CIPHER_AES
) {
2670 /* XXX Probably don't need to mention this. */
2671 logevent("AES not supported in SSH1, skipping");
2673 switch (next_cipher
) {
2674 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2675 cipher_string
= "3DES"; break;
2676 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2677 cipher_string
= "Blowfish"; break;
2678 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2679 cipher_string
= "single-DES"; break;
2681 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2685 if (!cipher_chosen
) {
2686 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2687 bombout(("Server violates SSH 1 protocol by not "
2688 "supporting 3DES encryption"));
2690 /* shouldn't happen */
2691 bombout(("No supported ciphers found"));
2695 /* Warn about chosen cipher if necessary. */
2697 askcipher(ssh
->frontend
, cipher_string
, 0);
2700 switch (s
->cipher_type
) {
2701 case SSH_CIPHER_3DES
:
2702 logevent("Using 3DES encryption");
2704 case SSH_CIPHER_DES
:
2705 logevent("Using single-DES encryption");
2707 case SSH_CIPHER_BLOWFISH
:
2708 logevent("Using Blowfish encryption");
2712 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
2713 PKT_CHAR
, s
->cipher_type
,
2714 PKT_DATA
, cookie
, 8,
2715 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
2716 PKT_DATA
, s
->rsabuf
, s
->len
,
2717 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
2719 logevent("Trying to enable encryption...");
2723 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2724 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
2726 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
2727 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
2728 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
2730 ssh
->crcda_ctx
= crcda_make_context();
2731 logevent("Installing CRC compensation attack detector");
2733 if (servkey
.modulus
) {
2734 sfree(servkey
.modulus
);
2735 servkey
.modulus
= NULL
;
2737 if (servkey
.exponent
) {
2738 sfree(servkey
.exponent
);
2739 servkey
.exponent
= NULL
;
2741 if (hostkey
.modulus
) {
2742 sfree(hostkey
.modulus
);
2743 hostkey
.modulus
= NULL
;
2745 if (hostkey
.exponent
) {
2746 sfree(hostkey
.exponent
);
2747 hostkey
.exponent
= NULL
;
2751 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2752 bombout(("Encryption not successfully enabled"));
2756 logevent("Successfully started encryption");
2760 if ((flags
& FLAG_INTERACTIVE
) && !*ssh
->cfg
.username
) {
2761 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2762 if (!ssh_get_line("login as: ",
2763 s
->username
, sizeof(s
->username
), FALSE
)) {
2765 * get_line failed to get a username.
2768 logevent("No username provided. Abandoning session.");
2769 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2773 int ret
; /* need not be kept over crReturn */
2774 c_write_str(ssh
, "login as: ");
2777 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
2779 crWaitUntil(!ispkt
);
2780 ret
= process_userpass_input(ssh
, in
, inlen
);
2784 c_write_str(ssh
, "\r\n");
2787 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
2788 s
->username
[sizeof(s
->username
)-1] = '\0';
2791 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
2793 char userlog
[22 + sizeof(s
->username
)];
2794 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
2796 if (flags
& FLAG_INTERACTIVE
&&
2797 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2798 strcat(userlog
, "\r\n");
2799 c_write_str(ssh
, userlog
);
2806 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2807 /* We must not attempt PK auth. Pretend we've already tried it. */
2808 s
->tried_publickey
= s
->tried_agent
= 1;
2810 s
->tried_publickey
= s
->tried_agent
= 0;
2812 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
2813 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
2814 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
2815 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
2816 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
2817 s
->publickey_blob
= NULL
;
2819 s
->publickey_blob
= NULL
;
2821 while (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
2822 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2824 if (agent_exists() && !s
->tried_agent
) {
2826 * Attempt RSA authentication using Pageant.
2832 logevent("Pageant is running. Requesting keys.");
2834 /* Request the keys held by the agent. */
2835 PUT_32BIT(s
->request
, 1);
2836 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2837 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
2838 ssh_agent_callback
, ssh
)) {
2842 bombout(("Unexpected data from server while waiting"
2843 " for agent response"));
2846 } while (ispkt
|| inlen
> 0);
2847 r
= ssh
->agent_response
;
2848 s
->responselen
= ssh
->agent_response_len
;
2850 s
->response
= (unsigned char *) r
;
2851 if (s
->response
&& s
->responselen
>= 5 &&
2852 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
2853 s
->p
= s
->response
+ 5;
2854 s
->nkeys
= GET_32BIT(s
->p
);
2858 sprintf(buf
, "Pageant has %d SSH1 keys", s
->nkeys
);
2861 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
2864 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
2867 if (s
->publickey_blob
&&
2868 !memcmp(s
->p
, s
->publickey_blob
,
2869 s
->publickey_bloblen
)) {
2870 logevent("This key matches configured key file");
2871 s
->tried_publickey
= 1;
2876 do { /* do while (0) to make breaking easy */
2877 n
= ssh1_read_bignum
2878 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
2883 n
= ssh1_read_bignum
2884 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
2889 if (s
->responselen
- (s
->p
-s
->response
) < 4)
2891 s
->commentlen
= GET_32BIT(s
->p
);
2893 if (s
->responselen
- (s
->p
-s
->response
) <
2896 s
->commentp
= (char *)s
->p
;
2897 s
->p
+= s
->commentlen
;
2901 logevent("Pageant key list packet was truncated");
2905 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
2906 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
2908 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2909 logevent("Key refused");
2912 logevent("Received RSA challenge");
2913 if ((s
->challenge
= ssh1_pkt_getmp(ssh
)) == NULL
) {
2914 bombout(("Server's RSA challenge was badly formatted"));
2919 char *agentreq
, *q
, *ret
;
2922 len
= 1 + 4; /* message type, bit count */
2923 len
+= ssh1_bignum_length(s
->key
.exponent
);
2924 len
+= ssh1_bignum_length(s
->key
.modulus
);
2925 len
+= ssh1_bignum_length(s
->challenge
);
2926 len
+= 16; /* session id */
2927 len
+= 4; /* response format */
2928 agentreq
= snewn(4 + len
, char);
2929 PUT_32BIT(agentreq
, len
);
2931 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
2932 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
2934 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
2935 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
2936 q
+= ssh1_write_bignum(q
, s
->challenge
);
2937 memcpy(q
, s
->session_id
, 16);
2939 PUT_32BIT(q
, 1); /* response format */
2940 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
2941 ssh_agent_callback
, ssh
)) {
2946 bombout(("Unexpected data from server"
2947 " while waiting for agent"
2951 } while (ispkt
|| inlen
> 0);
2952 vret
= ssh
->agent_response
;
2953 retlen
= ssh
->agent_response_len
;
2958 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
2959 logevent("Sending Pageant's response");
2960 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
2961 PKT_DATA
, ret
+ 5, 16,
2965 if (ssh
->pktin
.type
== SSH1_SMSG_SUCCESS
) {
2967 ("Pageant's response accepted");
2968 if (flags
& FLAG_VERBOSE
) {
2969 c_write_str(ssh
, "Authenticated using"
2971 c_write(ssh
, s
->commentp
,
2973 c_write_str(ssh
, "\" from agent\r\n");
2978 ("Pageant's response not accepted");
2981 ("Pageant failed to answer challenge");
2985 logevent("No reply received from Pageant");
2988 freebn(s
->key
.exponent
);
2989 freebn(s
->key
.modulus
);
2990 freebn(s
->challenge
);
2999 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
3000 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
3002 if (ssh
->cfg
.try_tis_auth
&&
3003 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3004 !s
->tis_auth_refused
) {
3005 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3006 logevent("Requested TIS authentication");
3007 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3009 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3010 logevent("TIS authentication declined");
3011 if (flags
& FLAG_INTERACTIVE
)
3012 c_write_str(ssh
, "TIS authentication refused.\r\n");
3013 s
->tis_auth_refused
= 1;
3019 ssh_pkt_getstring(ssh
, &challenge
, &challengelen
);
3021 bombout(("TIS challenge packet was badly formed"));
3024 logevent("Received TIS challenge");
3025 if (challengelen
> sizeof(s
->prompt
) - 1)
3026 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3027 memcpy(s
->prompt
, challenge
, challengelen
);
3028 /* Prompt heuristic comes from OpenSSH */
3029 strncpy(s
->prompt
+ challengelen
,
3030 memchr(s
->prompt
, '\n', challengelen
) ?
3031 "": "\r\nResponse: ",
3032 (sizeof s
->prompt
) - challengelen
);
3033 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
3036 if (ssh
->cfg
.try_tis_auth
&&
3037 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3038 !s
->ccard_auth_refused
) {
3039 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3040 logevent("Requested CryptoCard authentication");
3041 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3043 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3044 logevent("CryptoCard authentication declined");
3045 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3046 s
->ccard_auth_refused
= 1;
3052 ssh_pkt_getstring(ssh
, &challenge
, &challengelen
);
3054 bombout(("CryptoCard challenge packet was badly formed"));
3057 logevent("Received CryptoCard challenge");
3058 if (challengelen
> sizeof(s
->prompt
) - 1)
3059 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3060 memcpy(s
->prompt
, challenge
, challengelen
);
3061 strncpy(s
->prompt
+ challengelen
,
3062 memchr(s
->prompt
, '\n', challengelen
) ?
3063 "" : "\r\nResponse: ",
3064 sizeof(s
->prompt
) - challengelen
);
3065 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
3068 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3069 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
3070 s
->username
, ssh
->savedhost
);
3072 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3073 char *comment
= NULL
;
3076 if (flags
& FLAG_VERBOSE
)
3077 c_write_str(ssh
, "Trying public key authentication.\r\n");
3078 logeventf(ssh
, "Trying public key \"%s\"",
3079 filename_to_str(&ssh
->cfg
.keyfile
));
3080 type
= key_type(&ssh
->cfg
.keyfile
);
3081 if (type
!= SSH_KEYTYPE_SSH1
) {
3082 sprintf(msgbuf
, "Key is of wrong type (%s)",
3083 key_type_to_str(type
));
3085 c_write_str(ssh
, msgbuf
);
3086 c_write_str(ssh
, "\r\n");
3087 s
->tried_publickey
= 1;
3090 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
3091 if (flags
& FLAG_VERBOSE
)
3092 c_write_str(ssh
, "No passphrase required.\r\n");
3095 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
3100 * Show password prompt, having first obtained it via a TIS
3101 * or CryptoCard exchange if we're doing TIS or CryptoCard
3105 if (!ssh_get_line(s
->prompt
, s
->password
,
3106 sizeof(s
->password
), TRUE
)) {
3108 * get_line failed to get a password (for example
3109 * because one was supplied on the command line
3110 * which has already failed to work). Terminate.
3112 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
3113 PKT_STR
, "No more passwords available to try",
3115 logevent("Unable to authenticate");
3116 connection_fatal(ssh
->frontend
, "Unable to authenticate");
3117 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3121 /* Prompt may have come from server. We've munged it a bit, so
3122 * we know it to be zero-terminated at least once. */
3123 int ret
; /* need not be saved over crReturn */
3124 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3127 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3129 crWaitUntil(!ispkt
);
3130 ret
= process_userpass_input(ssh
, in
, inlen
);
3134 c_write_str(ssh
, "\r\n");
3138 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3140 * Try public key authentication with the specified
3143 s
->tried_publickey
= 1;
3146 const char *error
= NULL
;
3147 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3150 c_write_str(ssh
, "Couldn't load private key from ");
3151 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3152 c_write_str(ssh
, " (");
3153 c_write_str(ssh
, error
);
3154 c_write_str(ssh
, ").\r\n");
3155 continue; /* go and try password */
3158 c_write_str(ssh
, "Wrong passphrase.\r\n");
3159 s
->tried_publickey
= 0;
3160 continue; /* try again */
3165 * Send a public key attempt.
3167 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3168 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3171 if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3172 c_write_str(ssh
, "Server refused our public key.\r\n");
3173 continue; /* go and try password */
3175 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3176 bombout(("Bizarre response to offer of public key"));
3182 unsigned char buffer
[32];
3183 Bignum challenge
, response
;
3185 if ((challenge
= ssh1_pkt_getmp(ssh
)) == NULL
) {
3186 bombout(("Server's RSA challenge was badly formatted"));
3189 response
= rsadecrypt(challenge
, &s
->key
);
3190 freebn(s
->key
.private_exponent
);/* burn the evidence */
3192 for (i
= 0; i
< 32; i
++) {
3193 buffer
[i
] = bignum_byte(response
, 31 - i
);
3197 MD5Update(&md5c
, buffer
, 32);
3198 MD5Update(&md5c
, s
->session_id
, 16);
3199 MD5Final(buffer
, &md5c
);
3201 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3202 PKT_DATA
, buffer
, 16, PKT_END
);
3209 if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3210 if (flags
& FLAG_VERBOSE
)
3211 c_write_str(ssh
, "Failed to authenticate with"
3212 " our public key.\r\n");
3213 continue; /* go and try password */
3214 } else if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
) {
3215 bombout(("Bizarre response to RSA authentication response"));
3219 break; /* we're through! */
3221 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3223 * Defence against traffic analysis: we send a
3224 * whole bunch of packets containing strings of
3225 * different lengths. One of these strings is the
3226 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3227 * The others are all random data in
3228 * SSH1_MSG_IGNORE packets. This way a passive
3229 * listener can't tell which is the password, and
3230 * hence can't deduce the password length.
3232 * Anybody with a password length greater than 16
3233 * bytes is going to have enough entropy in their
3234 * password that a listener won't find it _that_
3235 * much help to know how long it is. So what we'll
3238 * - if password length < 16, we send 15 packets
3239 * containing string lengths 1 through 15
3241 * - otherwise, we let N be the nearest multiple
3242 * of 8 below the password length, and send 8
3243 * packets containing string lengths N through
3244 * N+7. This won't obscure the order of
3245 * magnitude of the password length, but it will
3246 * introduce a bit of extra uncertainty.
3248 * A few servers (the old 1.2.18 through 1.2.22)
3249 * can't deal with SSH1_MSG_IGNORE. For these
3250 * servers, we need an alternative defence. We make
3251 * use of the fact that the password is interpreted
3252 * as a C string: so we can append a NUL, then some
3255 * One server (a Cisco one) can deal with neither
3256 * SSH1_MSG_IGNORE _nor_ a padded password string.
3257 * For this server we are left with no defences
3258 * against password length sniffing.
3260 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3262 * The server can deal with SSH1_MSG_IGNORE, so
3263 * we can use the primary defence.
3265 int bottom
, top
, pwlen
, i
;
3268 pwlen
= strlen(s
->password
);
3270 bottom
= 0; /* zero length passwords are OK! :-) */
3273 bottom
= pwlen
& ~7;
3277 assert(pwlen
>= bottom
&& pwlen
<= top
);
3279 randomstr
= snewn(top
+ 1, char);
3281 for (i
= bottom
; i
<= top
; i
++) {
3283 defer_packet(ssh
, s
->pwpkt_type
,
3284 PKTT_PASSWORD
, PKT_STR
, s
->password
,
3285 PKTT_OTHER
, PKT_END
);
3287 for (j
= 0; j
< i
; j
++) {
3289 randomstr
[j
] = random_byte();
3290 } while (randomstr
[j
] == '\0');
3292 randomstr
[i
] = '\0';
3293 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3294 PKT_STR
, randomstr
, PKT_END
);
3297 logevent("Sending password with camouflage packets");
3298 ssh_pkt_defersend(ssh
);
3301 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3303 * The server can't deal with SSH1_MSG_IGNORE
3304 * but can deal with padded passwords, so we
3305 * can use the secondary defence.
3311 len
= strlen(s
->password
);
3312 if (len
< sizeof(string
)) {
3314 strcpy(string
, s
->password
);
3315 len
++; /* cover the zero byte */
3316 while (len
< sizeof(string
)) {
3317 string
[len
++] = (char) random_byte();
3322 logevent("Sending length-padded password");
3323 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3324 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3325 PKTT_OTHER
, PKT_END
);
3328 * The server has _both_
3329 * BUG_CHOKES_ON_SSH1_IGNORE and
3330 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3331 * therefore nothing we can do.
3334 len
= strlen(s
->password
);
3335 logevent("Sending unpadded password");
3336 send_packet(ssh
, s
->pwpkt_type
,
3337 PKTT_PASSWORD
, PKT_INT
, len
,
3338 PKT_DATA
, s
->password
, len
,
3339 PKTT_OTHER
, PKT_END
);
3342 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3343 PKT_STR
, s
->password
, PKTT_OTHER
, PKT_END
);
3346 logevent("Sent password");
3347 memset(s
->password
, 0, strlen(s
->password
));
3349 if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3350 if (flags
& FLAG_VERBOSE
)
3351 c_write_str(ssh
, "Access denied\r\n");
3352 logevent("Authentication refused");
3353 } else if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
) {
3354 bombout(("Strange packet received, type %d", ssh
->pktin
.type
));
3359 logevent("Authentication successful");
3364 void sshfwd_close(struct ssh_channel
*c
)
3368 if (ssh
->state
!= SSH_STATE_SESSION
) {
3369 assert(ssh
->state
== SSH_STATE_CLOSED
);
3373 if (c
&& !c
->closes
) {
3375 * If the channel's remoteid is -1, we have sent
3376 * CHANNEL_OPEN for this channel, but it hasn't even been
3377 * acknowledged by the server. So we must set a close flag
3378 * on it now, and then when the server acks the channel
3379 * open, we can close it then.
3381 if (((int)c
->remoteid
) != -1) {
3382 if (ssh
->version
== 1) {
3383 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3386 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_CLOSE
);
3387 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
3391 c
->closes
= 1; /* sent MSG_CLOSE */
3392 if (c
->type
== CHAN_X11
) {
3394 logevent("Forwarded X11 connection terminated");
3395 } else if (c
->type
== CHAN_SOCKDATA
||
3396 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3398 logevent("Forwarded port closed");
3403 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3407 if (ssh
->state
!= SSH_STATE_SESSION
) {
3408 assert(ssh
->state
== SSH_STATE_CLOSED
);
3412 if (ssh
->version
== 1) {
3413 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3414 PKT_INT
, c
->remoteid
,
3416 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3417 PKTT_OTHER
, PKT_END
);
3419 * In SSH1 we can return 0 here - implying that forwarded
3420 * connections are never individually throttled - because
3421 * the only circumstance that can cause throttling will be
3422 * the whole SSH connection backing up, in which case
3423 * _everything_ will be throttled as a whole.
3427 ssh2_add_channel_data(c
, buf
, len
);
3428 return ssh2_try_send(c
);
3432 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3436 if (ssh
->state
!= SSH_STATE_SESSION
) {
3437 assert(ssh
->state
== SSH_STATE_CLOSED
);
3441 if (ssh
->version
== 1) {
3442 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3443 c
->v
.v1
.throttling
= 0;
3444 ssh1_throttle(ssh
, -1);
3447 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3451 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
3453 crBegin(ssh
->ssh1_protocol_crstate
);
3457 while (!do_ssh1_login(ssh
, in
, inlen
, ispkt
)) {
3460 if (ssh
->state
== SSH_STATE_CLOSED
)
3463 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
3464 logevent("Requesting agent forwarding");
3465 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
3469 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3470 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3471 bombout(("Protocol confusion"));
3473 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3474 logevent("Agent forwarding refused");
3476 logevent("Agent forwarding enabled");
3477 ssh
->agentfwd_enabled
= TRUE
;
3481 if (ssh
->cfg
.x11_forward
) {
3482 char proto
[20], data
[64];
3483 logevent("Requesting X11 forwarding");
3484 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
3485 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
3486 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
3487 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
3488 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
3489 PKT_STR
, proto
, PKT_STR
, data
,
3490 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
3493 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
3494 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
3499 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3500 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3501 bombout(("Protocol confusion"));
3503 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3504 logevent("X11 forwarding refused");
3506 logevent("X11 forwarding enabled");
3507 ssh
->X11_fwd_enabled
= TRUE
;
3514 int sport
,dport
,sserv
,dserv
;
3515 char sports
[256], dports
[256], saddr
[256], host
[256];
3517 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3518 /* Add port forwardings. */
3519 ssh
->portfwd_strptr
= ssh
->cfg
.portfwd
;
3520 while (*ssh
->portfwd_strptr
) {
3521 type
= *ssh
->portfwd_strptr
++;
3524 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= '\t') {
3525 if (*ssh
->portfwd_strptr
== ':') {
3527 * We've seen a colon in the middle of the
3528 * source port number. This means that
3529 * everything we've seen until now is the
3530 * source _address_, so we'll move it into
3531 * saddr and start sports from the beginning
3534 ssh
->portfwd_strptr
++;
3536 strcpy(saddr
, sports
);
3539 if (n
< 255) sports
[n
++] = *ssh
->portfwd_strptr
++;
3543 if (*ssh
->portfwd_strptr
== '\t')
3544 ssh
->portfwd_strptr
++;
3546 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= ':') {
3547 if (n
< 255) host
[n
++] = *ssh
->portfwd_strptr
++;
3550 if (*ssh
->portfwd_strptr
== ':')
3551 ssh
->portfwd_strptr
++;
3553 while (*ssh
->portfwd_strptr
) {
3554 if (n
< 255) dports
[n
++] = *ssh
->portfwd_strptr
++;
3557 ssh
->portfwd_strptr
++;
3558 dport
= atoi(dports
);
3562 dport
= net_service_lookup(dports
);
3564 logeventf(ssh
, "Service lookup failed for"
3565 " destination port \"%s\"", dports
);
3569 while (*ssh
->portfwd_strptr
) ssh
->portfwd_strptr
++;
3571 ssh
->portfwd_strptr
++; /* eat the NUL and move to next one */
3573 sport
= atoi(sports
);
3577 sport
= net_service_lookup(sports
);
3579 logeventf(ssh
, "Service lookup failed for source"
3580 " port \"%s\"", sports
);
3583 if (sport
&& dport
) {
3584 /* Set up a description of the source port. */
3585 static char *sportdesc
;
3586 sportdesc
= dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
3587 (int)(*saddr?
strlen(saddr
):0), *saddr?saddr
:NULL
,
3588 (int)(*saddr?
1:0), ":",
3589 (int)(sserv ?
strlen(sports
) : 0), sports
,
3590 sserv
, "(", sport
, sserv
, ")");
3592 /* Verbose description of the destination port */
3593 char *dportdesc
= dupprintf("%s:%.*s%.*s%d%.*s",
3595 (int)(dserv ?
strlen(dports
) : 0), dports
,
3596 dserv
, "(", dport
, dserv
, ")");
3597 const char *err
= pfd_addforward(host
, dport
,
3598 *saddr ? saddr
: NULL
,
3599 sport
, ssh
, &ssh
->cfg
);
3601 logeventf(ssh
, "Local port %s forward to %s"
3602 " failed: %s", sportdesc
, dportdesc
, err
);
3604 logeventf(ssh
, "Local port %s forwarding to %s",
3605 sportdesc
, dportdesc
);
3608 } else if (type
== 'D') {
3609 const char *err
= pfd_addforward(NULL
, -1,
3610 *saddr ? saddr
: NULL
,
3611 sport
, ssh
, &ssh
->cfg
);
3613 logeventf(ssh
, "Local port %s SOCKS dynamic forward"
3614 " setup failed: %s", sportdesc
, err
);
3616 logeventf(ssh
, "Local port %s doing SOCKS"
3617 " dynamic forwarding", sportdesc
);
3620 struct ssh_rportfwd
*pf
;
3621 pf
= snew(struct ssh_rportfwd
);
3622 strcpy(pf
->dhost
, host
);
3626 "SSH1 cannot handle source address spec \"%s:%d\"; ignoring",
3629 if (add234(ssh
->rportfwds
, pf
) != pf
) {
3631 "Duplicate remote port forwarding to %s:%d",
3635 logeventf(ssh
, "Requesting remote port %.*s%.*s%d%.*s"
3636 " forward to %s:%.*s%.*s%d%.*s",
3637 (int)(sserv ?
strlen(sports
) : 0), sports
,
3638 sserv
, "(", sport
, sserv
, ")",
3640 (int)(dserv ?
strlen(dports
) : 0), dports
,
3641 dserv
, "(", dport
, dserv
, ")");
3642 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
3650 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3651 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3652 bombout(("Protocol confusion"));
3654 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3655 c_write_str(ssh
, "Server refused port"
3658 logevent("Remote port forwarding enabled");
3666 if (!ssh
->cfg
.nopty
) {
3667 /* Unpick the terminal-speed string. */
3668 /* XXX perhaps we should allow no speeds to be sent. */
3669 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
3670 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
3671 /* Send the pty request. */
3672 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
3673 PKT_STR
, ssh
->cfg
.termtype
,
3674 PKT_INT
, ssh
->term_height
,
3675 PKT_INT
, ssh
->term_width
,
3676 PKT_INT
, 0, PKT_INT
, 0, /* width,height in pixels */
3677 PKT_CHAR
, 192, PKT_INT
, ssh
->ispeed
, /* TTY_OP_ISPEED */
3678 PKT_CHAR
, 193, PKT_INT
, ssh
->ospeed
, /* TTY_OP_OSPEED */
3679 PKT_CHAR
, 0, PKT_END
);
3680 ssh
->state
= SSH_STATE_INTERMED
;
3684 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3685 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3686 bombout(("Protocol confusion"));
3688 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3689 c_write_str(ssh
, "Server refused to allocate pty\r\n");
3690 ssh
->editing
= ssh
->echoing
= 1;
3692 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
3693 ssh
->ospeed
, ssh
->ispeed
);
3695 ssh
->editing
= ssh
->echoing
= 1;
3698 if (ssh
->cfg
.compression
) {
3699 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
3703 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3704 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3705 bombout(("Protocol confusion"));
3707 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3708 c_write_str(ssh
, "Server refused to compress\r\n");
3710 logevent("Started compression");
3711 ssh
->v1_compressing
= TRUE
;
3712 ssh
->cs_comp_ctx
= zlib_compress_init();
3713 logevent("Initialised zlib (RFC1950) compression");
3714 ssh
->sc_comp_ctx
= zlib_decompress_init();
3715 logevent("Initialised zlib (RFC1950) decompression");
3719 * Start the shell or command.
3721 * Special case: if the first-choice command is an SSH2
3722 * subsystem (hence not usable here) and the second choice
3723 * exists, we fall straight back to that.
3726 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
3728 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
3729 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
3730 ssh
->fallback_cmd
= TRUE
;
3733 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
3735 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
3736 logevent("Started session");
3739 ssh
->state
= SSH_STATE_SESSION
;
3740 if (ssh
->size_needed
)
3741 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
3742 if (ssh
->eof_needed
)
3743 ssh_special(ssh
, TS_EOF
);
3746 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
3748 ssh
->channels
= newtree234(ssh_channelcmp
);
3752 if (ssh
->pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
3753 ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
3755 int stringlen
, bufsize
;
3757 ssh_pkt_getstring(ssh
, &string
, &stringlen
);
3758 if (string
== NULL
) {
3759 bombout(("Incoming terminal data packet was badly formed"));
3764 from_backend(ssh
->frontend
,
3765 ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
,
3767 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3768 ssh
->v1_stdout_throttling
= 1;
3769 ssh1_throttle(ssh
, +1);
3771 } else if (ssh
->pktin
.type
== SSH1_MSG_DISCONNECT
) {
3772 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3773 logevent("Received disconnect request");
3775 } else if (ssh
->pktin
.type
== SSH1_SMSG_X11_OPEN
) {
3776 /* Remote side is trying to open a channel to talk to our
3777 * X-Server. Give them back a local channel number. */
3778 struct ssh_channel
*c
;
3779 int remoteid
= ssh_pkt_getuint32(ssh
);
3781 logevent("Received X11 connect request");
3782 /* Refuse if X11 forwarding is disabled. */
3783 if (!ssh
->X11_fwd_enabled
) {
3784 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3785 PKT_INT
, remoteid
, PKT_END
);
3786 logevent("Rejected X11 connect request");
3788 c
= snew(struct ssh_channel
);
3791 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
3792 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
3793 logevent("Opening X11 forward connection failed");
3795 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3796 PKT_INT
, remoteid
, PKT_END
);
3799 ("Opening X11 forward connection succeeded");
3800 c
->remoteid
= remoteid
;
3801 c
->localid
= alloc_channel_id(ssh
);
3803 c
->v
.v1
.throttling
= 0;
3804 c
->type
= CHAN_X11
; /* identify channel type */
3805 add234(ssh
->channels
, c
);
3806 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3807 PKT_INT
, c
->remoteid
, PKT_INT
,
3808 c
->localid
, PKT_END
);
3809 logevent("Opened X11 forward channel");
3812 } else if (ssh
->pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
3813 /* Remote side is trying to open a channel to talk to our
3814 * agent. Give them back a local channel number. */
3815 struct ssh_channel
*c
;
3816 int remoteid
= ssh_pkt_getuint32(ssh
);
3818 /* Refuse if agent forwarding is disabled. */
3819 if (!ssh
->agentfwd_enabled
) {
3820 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3821 PKT_INT
, remoteid
, PKT_END
);
3823 c
= snew(struct ssh_channel
);
3825 c
->remoteid
= remoteid
;
3826 c
->localid
= alloc_channel_id(ssh
);
3828 c
->v
.v1
.throttling
= 0;
3829 c
->type
= CHAN_AGENT
; /* identify channel type */
3830 c
->u
.a
.lensofar
= 0;
3831 add234(ssh
->channels
, c
);
3832 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3833 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
3836 } else if (ssh
->pktin
.type
== SSH1_MSG_PORT_OPEN
) {
3837 /* Remote side is trying to open a channel to talk to a
3838 * forwarded port. Give them back a local channel number. */
3839 struct ssh_channel
*c
;
3840 struct ssh_rportfwd pf
;
3843 char *host
, buf
[1024];
3845 c
= snew(struct ssh_channel
);
3848 remoteid
= ssh_pkt_getuint32(ssh
);
3849 ssh_pkt_getstring(ssh
, &host
, &hostsize
);
3850 port
= ssh_pkt_getuint32(ssh
);
3852 if (hostsize
>= lenof(pf
.dhost
))
3853 hostsize
= lenof(pf
.dhost
)-1;
3854 memcpy(pf
.dhost
, host
, hostsize
);
3855 pf
.dhost
[hostsize
] = '\0';
3858 if (find234(ssh
->rportfwds
, &pf
, NULL
) == NULL
) {
3859 sprintf(buf
, "Rejected remote port open request for %s:%d",
3862 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3863 PKT_INT
, remoteid
, PKT_END
);
3865 sprintf(buf
, "Received remote port open request for %s:%d",
3868 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
3872 sprintf(buf
, "Port open failed: %s", e
);
3875 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3876 PKT_INT
, remoteid
, PKT_END
);
3878 c
->remoteid
= remoteid
;
3879 c
->localid
= alloc_channel_id(ssh
);
3881 c
->v
.v1
.throttling
= 0;
3882 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
3883 add234(ssh
->channels
, c
);
3884 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3885 PKT_INT
, c
->remoteid
, PKT_INT
,
3886 c
->localid
, PKT_END
);
3887 logevent("Forwarded port opened successfully");
3891 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
) {
3892 unsigned int remoteid
= ssh_pkt_getuint32(ssh
);
3893 unsigned int localid
= ssh_pkt_getuint32(ssh
);
3894 struct ssh_channel
*c
;
3896 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
3897 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3898 c
->remoteid
= localid
;
3899 c
->type
= CHAN_SOCKDATA
;
3900 c
->v
.v1
.throttling
= 0;
3901 pfd_confirm(c
->u
.pfd
.s
);
3904 if (c
&& c
->closes
) {
3906 * We have a pending close on this channel,
3907 * which we decided on before the server acked
3908 * the channel open. So now we know the
3909 * remoteid, we can close it again.
3911 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
3912 PKT_INT
, c
->remoteid
, PKT_END
);
3915 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_OPEN_FAILURE
) {
3916 unsigned int remoteid
= ssh_pkt_getuint32(ssh
);
3917 struct ssh_channel
*c
;
3919 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
3920 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3921 logevent("Forwarded connection refused by server");
3922 pfd_close(c
->u
.pfd
.s
);
3923 del234(ssh
->channels
, c
);
3927 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
3928 ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
3929 /* Remote side closes a channel. */
3930 unsigned i
= ssh_pkt_getuint32(ssh
);
3931 struct ssh_channel
*c
;
3932 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
3933 if (c
&& ((int)c
->remoteid
) != -1) {
3936 (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
3938 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
3939 logevent("Forwarded X11 connection terminated");
3940 assert(c
->u
.x11
.s
!= NULL
);
3941 x11_close(c
->u
.x11
.s
);
3944 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
3945 logevent("Forwarded port closed");
3946 assert(c
->u
.pfd
.s
!= NULL
);
3947 pfd_close(c
->u
.pfd
.s
);
3951 c
->closes
|= (closetype
<< 2); /* seen this message */
3952 if (!(c
->closes
& closetype
)) {
3953 send_packet(ssh
, ssh
->pktin
.type
, PKT_INT
, c
->remoteid
,
3955 c
->closes
|= closetype
; /* sent it too */
3958 if (c
->closes
== 15) {
3959 del234(ssh
->channels
, c
);
3963 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
3964 ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
3965 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
3969 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
3970 /* Data sent down one of our channels. */
3971 int i
= ssh_pkt_getuint32(ssh
);
3974 struct ssh_channel
*c
;
3976 ssh_pkt_getstring(ssh
, &p
, &len
);
3978 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
3983 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
3986 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
3989 /* Data for an agent message. Buffer it. */
3991 if (c
->u
.a
.lensofar
< 4) {
3992 int l
= min(4 - c
->u
.a
.lensofar
, len
);
3993 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
3997 c
->u
.a
.lensofar
+= l
;
3999 if (c
->u
.a
.lensofar
== 4) {
4001 4 + GET_32BIT(c
->u
.a
.msglen
);
4002 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
4004 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
4006 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
4008 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
4010 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
4014 c
->u
.a
.lensofar
+= l
;
4016 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
4019 if (agent_query(c
->u
.a
.message
,
4022 ssh_agentf_callback
, c
))
4023 ssh_agentf_callback(c
, reply
, replylen
);
4024 sfree(c
->u
.a
.message
);
4025 c
->u
.a
.lensofar
= 0;
4028 bufsize
= 0; /* agent channels never back up */
4031 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4032 c
->v
.v1
.throttling
= 1;
4033 ssh1_throttle(ssh
, +1);
4036 } else if (ssh
->pktin
.type
== SSH1_SMSG_SUCCESS
) {
4037 /* may be from EXEC_SHELL on some servers */
4038 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
4039 /* may be from EXEC_SHELL on some servers
4040 * if no pty is available or in other odd cases. Ignore */
4041 } else if (ssh
->pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
4043 ssh
->exitcode
= ssh_pkt_getuint32(ssh
);
4044 sprintf(buf
, "Server sent command exit status %d",
4047 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
4049 * In case `helpful' firewalls or proxies tack
4050 * extra human-readable text on the end of the
4051 * session which we might mistake for another
4052 * encrypted packet, we close the session once
4053 * we've sent EXIT_CONFIRMATION.
4055 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4058 bombout(("Strange packet received: type %d", ssh
->pktin
.type
));
4063 int len
= min(inlen
, 512);
4064 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4065 PKT_INT
, len
, PKT_DATA
, in
, len
,
4066 PKTT_OTHER
, PKT_END
);
4077 * Utility routine for decoding comma-separated strings in KEXINIT.
4079 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
4082 if (!needle
|| !haystack
) /* protect against null pointers */
4084 needlen
= strlen(needle
);
4087 * Is it at the start of the string?
4089 if (haylen
>= needlen
&& /* haystack is long enough */
4090 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4091 (haylen
== needlen
|| haystack
[needlen
] == ',')
4092 /* either , or EOS follows */
4096 * If not, search for the next comma and resume after that.
4097 * If no comma found, terminate.
4099 while (haylen
> 0 && *haystack
!= ',')
4100 haylen
--, haystack
++;
4103 haylen
--, haystack
++; /* skip over comma itself */
4108 * SSH2 key creation method.
4110 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
4111 unsigned char *sessid
, char chr
,
4112 unsigned char *keyspace
)
4115 /* First 20 bytes. */
4117 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4119 SHA_Bytes(&s
, H
, 20);
4120 SHA_Bytes(&s
, &chr
, 1);
4121 SHA_Bytes(&s
, sessid
, 20);
4122 SHA_Final(&s
, keyspace
);
4123 /* Next 20 bytes. */
4125 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4127 SHA_Bytes(&s
, H
, 20);
4128 SHA_Bytes(&s
, keyspace
, 20);
4129 SHA_Final(&s
, keyspace
+ 20);
4133 * Handle the SSH2 transport layer.
4135 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
4137 struct do_ssh2_transport_state
{
4138 int nbits
, pbits
, warn
;
4139 Bignum p
, g
, e
, f
, K
;
4140 int kex_init_value
, kex_reply_value
;
4141 const struct ssh_mac
**maclist
;
4143 const struct ssh2_cipher
*cscipher_tobe
;
4144 const struct ssh2_cipher
*sccipher_tobe
;
4145 const struct ssh_mac
*csmac_tobe
;
4146 const struct ssh_mac
*scmac_tobe
;
4147 const struct ssh_compress
*cscomp_tobe
;
4148 const struct ssh_compress
*sccomp_tobe
;
4149 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4150 int hostkeylen
, siglen
;
4151 void *hkey
; /* actual host key */
4152 unsigned char exchange_hash
[20];
4153 int n_preferred_ciphers
;
4154 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
4155 const struct ssh_compress
*preferred_comp
;
4158 crState(do_ssh2_transport_state
);
4160 crBegin(ssh
->do_ssh2_transport_crstate
);
4162 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
4163 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
4164 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
4172 * Set up the preferred ciphers. (NULL => warn below here)
4174 s
->n_preferred_ciphers
= 0;
4175 for (i
= 0; i
< CIPHER_MAX
; i
++) {
4176 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
4177 case CIPHER_BLOWFISH
:
4178 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
4181 if (ssh
->cfg
.ssh2_des_cbc
) {
4182 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
4186 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
4189 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
4192 /* Flag for later. Don't bother if it's the last in
4194 if (i
< CIPHER_MAX
- 1) {
4195 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
4203 * Set up preferred compression.
4205 if (ssh
->cfg
.compression
)
4206 s
->preferred_comp
= &ssh_zlib
;
4208 s
->preferred_comp
= &ssh_comp_none
;
4211 * Be prepared to work around the buggy MAC problem.
4213 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
4214 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
4216 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
4220 int i
, j
, cipherstr_started
;
4223 * Construct and send our key exchange packet.
4225 ssh2_pkt_init(ssh
, SSH2_MSG_KEXINIT
);
4226 for (i
= 0; i
< 16; i
++)
4227 ssh2_pkt_addbyte(ssh
, (unsigned char) random_byte());
4228 /* List key exchange algorithms. */
4229 ssh2_pkt_addstring_start(ssh
);
4230 for (i
= 0; i
< lenof(kex_algs
); i
++) {
4231 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
4232 (ssh
->remote_bugs
& BUG_SSH2_DH_GEX
))
4234 ssh2_pkt_addstring_str(ssh
, kex_algs
[i
]->name
);
4235 if (i
< lenof(kex_algs
) - 1)
4236 ssh2_pkt_addstring_str(ssh
, ",");
4238 /* List server host key algorithms. */
4239 ssh2_pkt_addstring_start(ssh
);
4240 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4241 ssh2_pkt_addstring_str(ssh
, hostkey_algs
[i
]->name
);
4242 if (i
< lenof(hostkey_algs
) - 1)
4243 ssh2_pkt_addstring_str(ssh
, ",");
4245 /* List client->server encryption algorithms. */
4246 ssh2_pkt_addstring_start(ssh
);
4247 cipherstr_started
= 0;
4248 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4249 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4250 if (!c
) continue; /* warning flag */
4251 for (j
= 0; j
< c
->nciphers
; j
++) {
4252 if (cipherstr_started
)
4253 ssh2_pkt_addstring_str(ssh
, ",");
4254 ssh2_pkt_addstring_str(ssh
, c
->list
[j
]->name
);
4255 cipherstr_started
= 1;
4258 /* List server->client encryption algorithms. */
4259 ssh2_pkt_addstring_start(ssh
);
4260 cipherstr_started
= 0;
4261 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4262 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4263 if (!c
) continue; /* warning flag */
4264 for (j
= 0; j
< c
->nciphers
; j
++) {
4265 if (cipherstr_started
)
4266 ssh2_pkt_addstring_str(ssh
, ",");
4267 ssh2_pkt_addstring_str(ssh
, c
->list
[j
]->name
);
4268 cipherstr_started
= 1;
4271 /* List client->server MAC algorithms. */
4272 ssh2_pkt_addstring_start(ssh
);
4273 for (i
= 0; i
< s
->nmacs
; i
++) {
4274 ssh2_pkt_addstring_str(ssh
, s
->maclist
[i
]->name
);
4275 if (i
< s
->nmacs
- 1)
4276 ssh2_pkt_addstring_str(ssh
, ",");
4278 /* List server->client MAC algorithms. */
4279 ssh2_pkt_addstring_start(ssh
);
4280 for (i
= 0; i
< s
->nmacs
; i
++) {
4281 ssh2_pkt_addstring_str(ssh
, s
->maclist
[i
]->name
);
4282 if (i
< s
->nmacs
- 1)
4283 ssh2_pkt_addstring_str(ssh
, ",");
4285 /* List client->server compression algorithms. */
4286 ssh2_pkt_addstring_start(ssh
);
4287 assert(lenof(compressions
) > 1);
4288 ssh2_pkt_addstring_str(ssh
, s
->preferred_comp
->name
);
4289 for (i
= 0; i
< lenof(compressions
); i
++) {
4290 const struct ssh_compress
*c
= compressions
[i
];
4291 if (c
!= s
->preferred_comp
) {
4292 ssh2_pkt_addstring_str(ssh
, ",");
4293 ssh2_pkt_addstring_str(ssh
, c
->name
);
4296 /* List server->client compression algorithms. */
4297 ssh2_pkt_addstring_start(ssh
);
4298 assert(lenof(compressions
) > 1);
4299 ssh2_pkt_addstring_str(ssh
, s
->preferred_comp
->name
);
4300 for (i
= 0; i
< lenof(compressions
); i
++) {
4301 const struct ssh_compress
*c
= compressions
[i
];
4302 if (c
!= s
->preferred_comp
) {
4303 ssh2_pkt_addstring_str(ssh
, ",");
4304 ssh2_pkt_addstring_str(ssh
, c
->name
);
4307 /* List client->server languages. Empty list. */
4308 ssh2_pkt_addstring_start(ssh
);
4309 /* List server->client languages. Empty list. */
4310 ssh2_pkt_addstring_start(ssh
);
4311 /* First KEX packet does _not_ follow, because we're not that brave. */
4312 ssh2_pkt_addbool(ssh
, FALSE
);
4314 ssh2_pkt_adduint32(ssh
, 0);
4317 ssh
->exhash
= ssh
->exhashbase
;
4318 sha_string(&ssh
->exhash
, ssh
->pktout
.data
+ 5, ssh
->pktout
.length
- 5);
4324 if (ssh
->pktin
.length
> 5)
4325 sha_string(&ssh
->exhash
, ssh
->pktin
.data
+ 5, ssh
->pktin
.length
- 5);
4328 * Now examine the other side's KEXINIT to see what we're up
4335 if (ssh
->pktin
.type
!= SSH2_MSG_KEXINIT
) {
4336 bombout(("expected key exchange packet from server"));
4340 ssh
->hostkey
= NULL
;
4341 s
->cscipher_tobe
= NULL
;
4342 s
->sccipher_tobe
= NULL
;
4343 s
->csmac_tobe
= NULL
;
4344 s
->scmac_tobe
= NULL
;
4345 s
->cscomp_tobe
= NULL
;
4346 s
->sccomp_tobe
= NULL
;
4347 ssh
->pktin
.savedpos
+= 16; /* skip garbage cookie */
4348 ssh_pkt_getstring(ssh
, &str
, &len
); /* key exchange algorithms */
4349 for (i
= 0; i
< lenof(kex_algs
); i
++) {
4350 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
4351 (ssh
->remote_bugs
& BUG_SSH2_DH_GEX
))
4353 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
4354 ssh
->kex
= kex_algs
[i
];
4358 ssh_pkt_getstring(ssh
, &str
, &len
); /* host key algorithms */
4359 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4360 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
4361 ssh
->hostkey
= hostkey_algs
[i
];
4365 ssh_pkt_getstring(ssh
, &str
, &len
); /* client->server cipher */
4367 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4368 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4372 for (j
= 0; j
< c
->nciphers
; j
++) {
4373 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4374 s
->cscipher_tobe
= c
->list
[j
];
4379 if (s
->cscipher_tobe
) {
4381 askcipher(ssh
->frontend
, s
->cscipher_tobe
->name
, 1);
4385 if (!s
->cscipher_tobe
) {
4386 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
4387 str ? str
: "(null)"));
4391 ssh_pkt_getstring(ssh
, &str
, &len
); /* server->client cipher */
4393 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4394 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4398 for (j
= 0; j
< c
->nciphers
; j
++) {
4399 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4400 s
->sccipher_tobe
= c
->list
[j
];
4405 if (s
->sccipher_tobe
) {
4407 askcipher(ssh
->frontend
, s
->sccipher_tobe
->name
, 2);
4411 if (!s
->sccipher_tobe
) {
4412 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
4413 str ? str
: "(null)"));
4417 ssh_pkt_getstring(ssh
, &str
, &len
); /* client->server mac */
4418 for (i
= 0; i
< s
->nmacs
; i
++) {
4419 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4420 s
->csmac_tobe
= s
->maclist
[i
];
4424 ssh_pkt_getstring(ssh
, &str
, &len
); /* server->client mac */
4425 for (i
= 0; i
< s
->nmacs
; i
++) {
4426 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4427 s
->scmac_tobe
= s
->maclist
[i
];
4431 ssh_pkt_getstring(ssh
, &str
, &len
); /* client->server compression */
4432 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4433 const struct ssh_compress
*c
=
4434 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4435 if (in_commasep_string(c
->name
, str
, len
)) {
4440 ssh_pkt_getstring(ssh
, &str
, &len
); /* server->client compression */
4441 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4442 const struct ssh_compress
*c
=
4443 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4444 if (in_commasep_string(c
->name
, str
, len
)) {
4452 * Work out the number of bits of key we will need from the key
4453 * exchange. We start with the maximum key length of either
4459 csbits
= s
->cscipher_tobe
->keylen
;
4460 scbits
= s
->sccipher_tobe
->keylen
;
4461 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
4463 /* The keys only have 160-bit entropy, since they're based on
4464 * a SHA-1 hash. So cap the key size at 160 bits. */
4469 * If we're doing Diffie-Hellman group exchange, start by
4470 * requesting a group.
4472 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4473 logevent("Doing Diffie-Hellman group exchange");
4474 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
4476 * Work out how big a DH group we will need to allow that
4479 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
4480 ssh2_pkt_init(ssh
, SSH2_MSG_KEX_DH_GEX_REQUEST
);
4481 ssh2_pkt_adduint32(ssh
, s
->pbits
);
4485 if (ssh
->pktin
.type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
4486 bombout(("expected key exchange group packet from server"));
4489 s
->p
= ssh2_pkt_getmp(ssh
);
4490 s
->g
= ssh2_pkt_getmp(ssh
);
4491 ssh
->kex_ctx
= dh_setup_group(s
->p
, s
->g
);
4492 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
4493 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
4495 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP1
;
4496 ssh
->kex_ctx
= dh_setup_group1();
4497 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
4498 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
4501 logevent("Doing Diffie-Hellman key exchange");
4503 * Now generate and send e for Diffie-Hellman.
4505 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
4506 ssh2_pkt_init(ssh
, s
->kex_init_value
);
4507 ssh2_pkt_addmp(ssh
, s
->e
);
4511 if (ssh
->pktin
.type
!= s
->kex_reply_value
) {
4512 bombout(("expected key exchange reply packet from server"));
4515 ssh_pkt_getstring(ssh
, &s
->hostkeydata
, &s
->hostkeylen
);
4516 s
->f
= ssh2_pkt_getmp(ssh
);
4517 ssh_pkt_getstring(ssh
, &s
->sigdata
, &s
->siglen
);
4519 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
4521 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
4522 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4523 sha_uint32(&ssh
->exhash
, s
->pbits
);
4524 sha_mpint(&ssh
->exhash
, s
->p
);
4525 sha_mpint(&ssh
->exhash
, s
->g
);
4527 sha_mpint(&ssh
->exhash
, s
->e
);
4528 sha_mpint(&ssh
->exhash
, s
->f
);
4529 sha_mpint(&ssh
->exhash
, s
->K
);
4530 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
4532 dh_cleanup(ssh
->kex_ctx
);
4533 ssh
->kex_ctx
= NULL
;
4536 debug(("Exchange hash is:\n"));
4537 dmemdump(s
->exchange_hash
, 20);
4540 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
4542 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
4543 (char *)s
->exchange_hash
, 20)) {
4544 bombout(("Server's host key did not match the signature supplied"));
4549 * Authenticate remote host: verify host key. (We've already
4550 * checked the signature of the exchange hash.)
4552 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
4553 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
4554 verify_ssh_host_key(ssh
->frontend
,
4555 ssh
->savedhost
, ssh
->savedport
, ssh
->hostkey
->keytype
,
4556 s
->keystr
, s
->fingerprint
);
4557 if (s
->first_kex
) { /* don't bother logging this in rekeys */
4558 logevent("Host key fingerprint is:");
4559 logevent(s
->fingerprint
);
4561 sfree(s
->fingerprint
);
4563 ssh
->hostkey
->freekey(s
->hkey
);
4566 * Send SSH2_MSG_NEWKEYS.
4568 ssh2_pkt_init(ssh
, SSH2_MSG_NEWKEYS
);
4572 * Expect SSH2_MSG_NEWKEYS from server.
4575 if (ssh
->pktin
.type
!= SSH2_MSG_NEWKEYS
) {
4576 bombout(("expected new-keys packet from server"));
4581 * Create and initialise session keys.
4583 if (ssh
->cs_cipher_ctx
)
4584 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
4585 ssh
->cscipher
= s
->cscipher_tobe
;
4586 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
4588 if (ssh
->sc_cipher_ctx
)
4589 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
4590 ssh
->sccipher
= s
->sccipher_tobe
;
4591 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
4593 if (ssh
->cs_mac_ctx
)
4594 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
4595 ssh
->csmac
= s
->csmac_tobe
;
4596 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
4598 if (ssh
->sc_mac_ctx
)
4599 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
4600 ssh
->scmac
= s
->scmac_tobe
;
4601 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
4603 if (ssh
->cs_comp_ctx
)
4604 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
4605 ssh
->cscomp
= s
->cscomp_tobe
;
4606 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
4608 if (ssh
->sc_comp_ctx
)
4609 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
4610 ssh
->sccomp
= s
->sccomp_tobe
;
4611 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
4614 * Set IVs after keys. Here we use the exchange hash from the
4615 * _first_ key exchange.
4618 unsigned char keyspace
[40];
4620 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
4621 sizeof(s
->exchange_hash
));
4622 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
4623 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
4624 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
4625 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
4626 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
4627 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
4628 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
4629 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
4630 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
4631 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
4632 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
4633 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
4635 logeventf(ssh
, "Initialised %.200s client->server encryption",
4636 ssh
->cscipher
->text_name
);
4637 logeventf(ssh
, "Initialised %.200s server->client encryption",
4638 ssh
->sccipher
->text_name
);
4639 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
4640 ssh
->csmac
->text_name
);
4641 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
4642 ssh
->scmac
->text_name
);
4643 if (ssh
->cscomp
->text_name
)
4644 logeventf(ssh
, "Initialised %s compression",
4645 ssh
->cscomp
->text_name
);
4646 if (ssh
->sccomp
->text_name
)
4647 logeventf(ssh
, "Initialised %s decompression",
4648 ssh
->sccomp
->text_name
);
4651 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4657 * If this is the first key exchange phase, we must pass the
4658 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
4659 * wants to see it but because it will need time to initialise
4660 * itself before it sees an actual packet. In subsequent key
4661 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
4662 * it would only confuse the layer above.
4664 if (!s
->first_kex
) {
4670 * Now we're encrypting. Begin returning 1 to the protocol main
4671 * function so that other things can run on top of the
4672 * transport. If we ever see a KEXINIT, we must go back to the
4675 while (!(ispkt
&& ssh
->pktin
.type
== SSH2_MSG_KEXINIT
)) {
4678 logevent("Server initiated key re-exchange");
4679 goto begin_key_exchange
;
4685 * Add data to an SSH2 channel output buffer.
4687 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
4690 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
4694 * Attempt to send data on an SSH2 channel.
4696 static int ssh2_try_send(struct ssh_channel
*c
)
4700 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
4703 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
4704 if ((unsigned)len
> c
->v
.v2
.remwindow
)
4705 len
= c
->v
.v2
.remwindow
;
4706 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
4707 len
= c
->v
.v2
.remmaxpkt
;
4708 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_DATA
);
4709 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
4710 dont_log_data(ssh
, PKTLOG_OMIT
);
4711 ssh2_pkt_addstring_start(ssh
);
4712 ssh2_pkt_addstring_data(ssh
, data
, len
);
4713 end_log_omission(ssh
);
4715 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
4716 c
->v
.v2
.remwindow
-= len
;
4720 * After having sent as much data as we can, return the amount
4723 return bufchain_size(&c
->v
.v2
.outbuffer
);
4727 * Potentially enlarge the window on an SSH2 channel.
4729 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
4734 * Never send WINDOW_ADJUST for a channel that the remote side
4735 * already thinks it's closed; there's no point, since it won't
4736 * be sending any more data anyway.
4741 if (newwin
> c
->v
.v2
.locwindow
) {
4742 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4743 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
4744 ssh2_pkt_adduint32(ssh
, newwin
- c
->v
.v2
.locwindow
);
4746 c
->v
.v2
.locwindow
= newwin
;
4751 * Handle the SSH2 userauth and connection layers.
4753 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
4755 struct do_ssh2_authconn_state
{
4757 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
4759 AUTH_KEYBOARD_INTERACTIVE
4763 AUTH_TYPE_PUBLICKEY
,
4764 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
4765 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
4767 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
4768 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4770 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
4771 int tried_pubkey_config
, tried_agent
, tried_keyb_inter
;
4772 int kbd_inter_running
;
4774 int num_prompts
, curr_prompt
, echo
;
4779 void *publickey_blob
;
4780 int publickey_bloblen
;
4781 unsigned char request
[5], *response
, *p
;
4785 char *pkblob
, *alg
, *commentp
;
4786 int pklen
, alglen
, commentlen
;
4787 int siglen
, retlen
, len
;
4788 char *q
, *agentreq
, *ret
;
4790 int num_env
, env_left
, env_ok
;
4792 crState(do_ssh2_authconn_state
);
4794 crBegin(ssh
->do_ssh2_authconn_crstate
);
4797 * Request userauth protocol, and await a response to it.
4799 ssh2_pkt_init(ssh
, SSH2_MSG_SERVICE_REQUEST
);
4800 ssh2_pkt_addstring(ssh
, "ssh-userauth");
4802 crWaitUntilV(ispkt
);
4803 if (ssh
->pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
4804 bombout(("Server refused user authentication protocol"));
4809 * We repeat this whole loop, including the username prompt,
4810 * until we manage a successful authentication. If the user
4811 * types the wrong _password_, they can be sent back to the
4812 * beginning to try another username, if this is configured on.
4813 * (If they specify a username in the config, they are never
4814 * asked, even if they do give a wrong password.)
4816 * I think this best serves the needs of
4818 * - the people who have no configuration, no keys, and just
4819 * want to try repeated (username,password) pairs until they
4820 * type both correctly
4822 * - people who have keys and configuration but occasionally
4823 * need to fall back to passwords
4825 * - people with a key held in Pageant, who might not have
4826 * logged in to a particular machine before; so they want to
4827 * type a username, and then _either_ their key will be
4828 * accepted, _or_ they will type a password. If they mistype
4829 * the username they will want to be able to get back and
4832 s
->username
[0] = '\0';
4833 s
->got_username
= FALSE
;
4838 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
4840 * We got a username last time round this loop, and
4841 * with change_username turned off we don't try to get
4844 } else if ((flags
& FLAG_INTERACTIVE
) && !*ssh
->cfg
.username
) {
4845 if (ssh_get_line
&& !ssh_getline_pw_only
) {
4846 if (!ssh_get_line("login as: ",
4847 s
->username
, sizeof(s
->username
), FALSE
)) {
4849 * get_line failed to get a username.
4852 logevent("No username provided. Abandoning session.");
4853 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4857 int ret
; /* need not be saved across crReturn */
4858 c_write_str(ssh
, "login as: ");
4860 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
4862 crWaitUntilV(!ispkt
);
4863 ret
= process_userpass_input(ssh
, in
, inlen
);
4867 c_write_str(ssh
, "\r\n");
4869 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
4872 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
4873 s
->username
[sizeof(s
->username
)-1] = '\0';
4874 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
4875 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
4876 c_write_str(ssh
, stuff
);
4880 s
->got_username
= TRUE
;
4883 * Send an authentication request using method "none": (a)
4884 * just in case it succeeds, and (b) so that we know what
4885 * authentication methods we can usefully try next.
4887 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4889 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4890 ssh2_pkt_addstring(ssh
, s
->username
);
4891 ssh2_pkt_addstring(ssh
, "ssh-connection");/* service requested */
4892 ssh2_pkt_addstring(ssh
, "none"); /* method */
4894 s
->type
= AUTH_TYPE_NONE
;
4896 s
->we_are_in
= FALSE
;
4898 s
->tried_pubkey_config
= FALSE
;
4899 s
->tried_agent
= FALSE
;
4900 s
->tried_keyb_inter
= FALSE
;
4901 s
->kbd_inter_running
= FALSE
;
4902 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
4903 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
4905 logeventf(ssh
, "Reading private key file \"%.150s\"",
4906 filename_to_str(&ssh
->cfg
.keyfile
));
4907 keytype
= key_type(&ssh
->cfg
.keyfile
);
4908 if (keytype
== SSH_KEYTYPE_SSH2
) {
4910 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
4911 &s
->publickey_bloblen
, NULL
);
4914 logeventf(ssh
, "Unable to use this key file (%s)",
4915 key_type_to_str(keytype
));
4916 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
4918 filename_to_str(&ssh
->cfg
.keyfile
),
4919 key_type_to_str(keytype
));
4920 c_write_str(ssh
, msgbuf
);
4922 s
->publickey_blob
= NULL
;
4925 s
->publickey_blob
= NULL
;
4929 * Wait for the result of the last authentication request.
4932 crWaitUntilV(ispkt
);
4933 while (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_BANNER
) {
4937 * Don't show the banner if we're operating in
4938 * non-verbose non-interactive mode. (It's probably
4939 * a script, which means nobody will read the
4940 * banner _anyway_, and moreover the printing of
4941 * the banner will screw up processing on the
4942 * output of (say) plink.)
4944 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
4945 ssh_pkt_getstring(ssh
, &banner
, &size
);
4947 c_write_untrusted(ssh
, banner
, size
);
4949 crWaitUntilV(ispkt
);
4951 if (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_SUCCESS
) {
4952 logevent("Access granted");
4953 s
->we_are_in
= TRUE
;
4957 if (s
->kbd_inter_running
&&
4958 ssh
->pktin
.type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4960 * This is either a further set-of-prompts packet
4961 * in keyboard-interactive authentication, or it's
4962 * the same one and we came back here with `gotit'
4963 * set. In the former case, we must reset the
4964 * curr_prompt variable.
4968 } else if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_FAILURE
) {
4969 bombout(("Strange packet received during authentication: type %d",
4977 * OK, we're now sitting on a USERAUTH_FAILURE message, so
4978 * we can look at the string in it and know what we can
4979 * helpfully try next.
4981 if (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
) {
4984 ssh_pkt_getstring(ssh
, &methods
, &methlen
);
4985 s
->kbd_inter_running
= FALSE
;
4986 if (!ssh2_pkt_getbool(ssh
)) {
4988 * We have received an unequivocal Access
4989 * Denied. This can translate to a variety of
4992 * - if we'd just tried "none" authentication,
4993 * it's not worth printing anything at all
4995 * - if we'd just tried a public key _offer_,
4996 * the message should be "Server refused our
4997 * key" (or no message at all if the key
4998 * came from Pageant)
5000 * - if we'd just tried anything else, the
5001 * message really should be "Access denied".
5003 * Additionally, if we'd just tried password
5004 * authentication, we should break out of this
5005 * whole loop so as to go back to the username
5008 if (s
->type
== AUTH_TYPE_NONE
) {
5010 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
5011 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
5012 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
5013 c_write_str(ssh
, "Server refused our key\r\n");
5014 logevent("Server refused public key");
5015 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
5016 /* server declined keyboard-interactive; ignore */
5018 c_write_str(ssh
, "Access denied\r\n");
5019 logevent("Access denied");
5020 if (s
->type
== AUTH_TYPE_PASSWORD
) {
5021 s
->we_are_in
= FALSE
;
5026 c_write_str(ssh
, "Further authentication required\r\n");
5027 logevent("Further authentication required");
5031 in_commasep_string("publickey", methods
, methlen
);
5033 in_commasep_string("password", methods
, methlen
);
5034 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
5035 in_commasep_string("keyboard-interactive", methods
, methlen
);
5039 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5043 * Most password/passphrase prompts will be
5044 * non-echoing, so we set this to 0 by default.
5045 * Exception is that some keyboard-interactive prompts
5046 * can be echoing, in which case we'll set this to 1.
5050 if (!s
->method
&& s
->can_pubkey
&&
5051 agent_exists() && !s
->tried_agent
) {
5053 * Attempt public-key authentication using Pageant.
5058 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5059 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
5061 s
->tried_agent
= TRUE
;
5063 logevent("Pageant is running. Requesting keys.");
5065 /* Request the keys held by the agent. */
5066 PUT_32BIT(s
->request
, 1);
5067 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
5068 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
5069 ssh_agent_callback
, ssh
)) {
5073 bombout(("Unexpected data from server while"
5074 " waiting for agent response"));
5077 } while (ispkt
|| inlen
> 0);
5078 r
= ssh
->agent_response
;
5079 s
->responselen
= ssh
->agent_response_len
;
5081 s
->response
= (unsigned char *) r
;
5082 if (s
->response
&& s
->responselen
>= 5 &&
5083 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
5084 s
->p
= s
->response
+ 5;
5085 s
->nkeys
= GET_32BIT(s
->p
);
5089 sprintf(buf
, "Pageant has %d SSH2 keys", s
->nkeys
);
5092 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
5097 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
5100 s
->pklen
= GET_32BIT(s
->p
);
5102 if (s
->publickey_blob
&&
5103 s
->pklen
== s
->publickey_bloblen
&&
5104 !memcmp(s
->p
, s
->publickey_blob
,
5105 s
->publickey_bloblen
)) {
5106 logevent("This key matches configured key file");
5107 s
->tried_pubkey_config
= 1;
5109 s
->pkblob
= (char *)s
->p
;
5111 s
->alglen
= GET_32BIT(s
->pkblob
);
5112 s
->alg
= s
->pkblob
+ 4;
5113 s
->commentlen
= GET_32BIT(s
->p
);
5115 s
->commentp
= (char *)s
->p
;
5116 s
->p
+= s
->commentlen
;
5117 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
5118 ssh2_pkt_addstring(ssh
, s
->username
);
5119 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
5120 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
5121 ssh2_pkt_addbool(ssh
, FALSE
); /* no signature included */
5122 ssh2_pkt_addstring_start(ssh
);
5123 ssh2_pkt_addstring_data(ssh
, s
->alg
, s
->alglen
);
5124 ssh2_pkt_addstring_start(ssh
);
5125 ssh2_pkt_addstring_data(ssh
, s
->pkblob
, s
->pklen
);
5128 crWaitUntilV(ispkt
);
5129 if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
5130 logevent("Key refused");
5134 if (flags
& FLAG_VERBOSE
) {
5135 c_write_str(ssh
, "Authenticating with "
5137 c_write(ssh
, s
->commentp
, s
->commentlen
);
5138 c_write_str(ssh
, "\" from agent\r\n");
5142 * Server is willing to accept the key.
5143 * Construct a SIGN_REQUEST.
5145 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
5146 ssh2_pkt_addstring(ssh
, s
->username
);
5147 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
5148 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
5149 ssh2_pkt_addbool(ssh
, TRUE
);
5150 ssh2_pkt_addstring_start(ssh
);
5151 ssh2_pkt_addstring_data(ssh
, s
->alg
, s
->alglen
);
5152 ssh2_pkt_addstring_start(ssh
);
5153 ssh2_pkt_addstring_data(ssh
, s
->pkblob
, s
->pklen
);
5155 s
->siglen
= ssh
->pktout
.length
- 5 + 4 + 20;
5156 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
5158 s
->len
= 1; /* message type */
5159 s
->len
+= 4 + s
->pklen
; /* key blob */
5160 s
->len
+= 4 + s
->siglen
; /* data to sign */
5161 s
->len
+= 4; /* flags */
5162 s
->agentreq
= snewn(4 + s
->len
, char);
5163 PUT_32BIT(s
->agentreq
, s
->len
);
5164 s
->q
= s
->agentreq
+ 4;
5165 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
5166 PUT_32BIT(s
->q
, s
->pklen
);
5168 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
5170 PUT_32BIT(s
->q
, s
->siglen
);
5172 /* Now the data to be signed... */
5173 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
5174 PUT_32BIT(s
->q
, 20);
5177 memcpy(s
->q
, ssh
->v2_session_id
, 20);
5179 memcpy(s
->q
, ssh
->pktout
.data
+ 5,
5180 ssh
->pktout
.length
- 5);
5181 s
->q
+= ssh
->pktout
.length
- 5;
5182 /* And finally the (zero) flags word. */
5184 if (!agent_query(s
->agentreq
, s
->len
+ 4,
5186 ssh_agent_callback
, ssh
)) {
5190 bombout(("Unexpected data from server"
5191 " while waiting for agent"
5195 } while (ispkt
|| inlen
> 0);
5196 vret
= ssh
->agent_response
;
5197 s
->retlen
= ssh
->agent_response_len
;
5202 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
5203 logevent("Sending Pageant's response");
5204 ssh2_add_sigblob(ssh
, s
->pkblob
, s
->pklen
,
5206 GET_32BIT(s
->ret
+ 5));
5212 ("Pageant failed to answer challenge");
5223 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
5224 && !s
->tried_pubkey_config
) {
5225 unsigned char *pub_blob
;
5226 char *algorithm
, *comment
;
5229 s
->tried_pubkey_config
= TRUE
;
5231 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5232 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
5235 * Try the public key supplied in the configuration.
5237 * First, offer the public blob to see if the server is
5238 * willing to accept it.
5241 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
5246 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
5247 ssh2_pkt_addstring(ssh
, s
->username
);
5248 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
5249 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
5250 ssh2_pkt_addbool(ssh
, FALSE
); /* no signature included */
5251 ssh2_pkt_addstring(ssh
, algorithm
);
5252 ssh2_pkt_addstring_start(ssh
);
5253 ssh2_pkt_addstring_data(ssh
, (char *)pub_blob
,
5256 logevent("Offered public key");
5258 crWaitUntilV(ispkt
);
5259 if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
5261 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
5262 continue; /* key refused; give up on it */
5265 logevent("Offer of public key accepted");
5267 * Actually attempt a serious authentication using
5270 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
5271 sprintf(s
->pwprompt
,
5272 "Passphrase for key \"%.100s\": ",
5278 if (flags
& FLAG_VERBOSE
) {
5279 c_write_str(ssh
, "Authenticating with public key \"");
5280 c_write_str(ssh
, comment
);
5281 c_write_str(ssh
, "\"\r\n");
5283 s
->method
= AUTH_PUBLICKEY_FILE
;
5287 if (!s
->method
&& s
->can_keyb_inter
&& !s
->tried_keyb_inter
) {
5288 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
5289 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
5290 s
->tried_keyb_inter
= TRUE
;
5292 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5293 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
5295 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
5296 ssh2_pkt_addstring(ssh
, s
->username
);
5297 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
5298 ssh2_pkt_addstring(ssh
, "keyboard-interactive"); /* method */
5299 ssh2_pkt_addstring(ssh
, ""); /* lang */
5300 ssh2_pkt_addstring(ssh
, "");
5303 crWaitUntilV(ispkt
);
5304 if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
5305 if (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
)
5307 logevent("Keyboard-interactive authentication refused");
5308 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
5312 s
->kbd_inter_running
= TRUE
;
5316 if (s
->kbd_inter_running
) {
5317 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
5318 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
5319 s
->tried_keyb_inter
= TRUE
;
5321 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5322 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
5324 if (s
->curr_prompt
== 0) {
5326 * We've got a fresh USERAUTH_INFO_REQUEST.
5327 * Display header data, and start going through
5330 char *name
, *inst
, *lang
;
5331 int name_len
, inst_len
, lang_len
;
5333 ssh_pkt_getstring(ssh
, &name
, &name_len
);
5334 ssh_pkt_getstring(ssh
, &inst
, &inst_len
);
5335 ssh_pkt_getstring(ssh
, &lang
, &lang_len
);
5337 c_write_untrusted(ssh
, name
, name_len
);
5338 c_write_str(ssh
, "\r\n");
5341 c_write_untrusted(ssh
, inst
, inst_len
);
5342 c_write_str(ssh
, "\r\n");
5344 s
->num_prompts
= ssh_pkt_getuint32(ssh
);
5348 * If there are prompts remaining in the packet,
5349 * display one and get a response.
5351 if (s
->curr_prompt
< s
->num_prompts
) {
5355 ssh_pkt_getstring(ssh
, &prompt
, &prompt_len
);
5356 if (prompt_len
> 0) {
5357 static const char trunc
[] = "<prompt truncated>: ";
5358 static const int prlen
= sizeof(s
->pwprompt
) -
5360 if (prompt_len
> prlen
) {
5361 memcpy(s
->pwprompt
, prompt
, prlen
);
5362 strcpy(s
->pwprompt
+ prlen
, trunc
);
5364 memcpy(s
->pwprompt
, prompt
, prompt_len
);
5365 s
->pwprompt
[prompt_len
] = '\0';
5369 "<server failed to send prompt>: ");
5371 s
->echo
= ssh2_pkt_getbool(ssh
);
5377 if (!s
->method
&& s
->can_passwd
) {
5378 s
->method
= AUTH_PASSWORD
;
5379 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
5380 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
5381 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
5388 if (!ssh_get_line(s
->pwprompt
, s
->password
,
5389 sizeof(s
->password
), TRUE
)) {
5391 * get_line failed to get a password (for
5392 * example because one was supplied on the
5393 * command line which has already failed to
5396 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
5397 ssh2_pkt_adduint32(ssh
,SSH2_DISCONNECT_BY_APPLICATION
);
5398 ssh2_pkt_addstring(ssh
, "No more passwords available"
5400 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
5402 logevent("Unable to authenticate");
5403 connection_fatal(ssh
->frontend
,
5404 "Unable to authenticate");
5405 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5409 int ret
; /* need not be saved across crReturn */
5410 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
5413 setup_userpass_input(ssh
, s
->password
,
5414 sizeof(s
->password
), s
->echo
);
5416 crWaitUntilV(!ispkt
);
5417 ret
= process_userpass_input(ssh
, in
, inlen
);
5421 c_write_str(ssh
, "\r\n");
5425 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
5427 * We have our passphrase. Now try the actual authentication.
5429 struct ssh2_userkey
*key
;
5430 const char *error
= NULL
;
5432 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
,
5434 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
5435 if (key
== SSH2_WRONG_PASSPHRASE
) {
5436 c_write_str(ssh
, "Wrong passphrase\r\n");
5437 s
->tried_pubkey_config
= FALSE
;
5439 c_write_str(ssh
, "Unable to load private key (");
5440 c_write_str(ssh
, error
);
5441 c_write_str(ssh
, ")\r\n");
5442 s
->tried_pubkey_config
= TRUE
;
5444 /* Send a spurious AUTH_NONE to return to the top. */
5445 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
5446 ssh2_pkt_addstring(ssh
, s
->username
);
5447 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
5448 ssh2_pkt_addstring(ssh
, "none"); /* method */
5450 s
->type
= AUTH_TYPE_NONE
;
5452 unsigned char *pkblob
, *sigblob
, *sigdata
;
5453 int pkblob_len
, sigblob_len
, sigdata_len
;
5457 * We have loaded the private key and the server
5458 * has announced that it's willing to accept it.
5459 * Hallelujah. Generate a signature and send it.
5461 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
5462 ssh2_pkt_addstring(ssh
, s
->username
);
5463 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
5464 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
5465 ssh2_pkt_addbool(ssh
, TRUE
);
5466 ssh2_pkt_addstring(ssh
, key
->alg
->name
);
5467 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
5468 ssh2_pkt_addstring_start(ssh
);
5469 ssh2_pkt_addstring_data(ssh
, (char *)pkblob
, pkblob_len
);
5472 * The data to be signed is:
5476 * followed by everything so far placed in the
5479 sigdata_len
= ssh
->pktout
.length
- 5 + 4 + 20;
5480 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
5482 sigdata
= snewn(sigdata_len
, unsigned char);
5484 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
5485 PUT_32BIT(sigdata
+p
, 20);
5488 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
5489 memcpy(sigdata
+p
, ssh
->pktout
.data
+ 5,
5490 ssh
->pktout
.length
- 5);
5491 p
+= ssh
->pktout
.length
- 5;
5492 assert(p
== sigdata_len
);
5493 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
5494 sigdata_len
, &sigblob_len
);
5495 ssh2_add_sigblob(ssh
, pkblob
, pkblob_len
,
5496 sigblob
, sigblob_len
);
5502 s
->type
= AUTH_TYPE_PUBLICKEY
;
5503 key
->alg
->freekey(key
->data
);
5505 } else if (s
->method
== AUTH_PASSWORD
) {
5507 * We send the password packet lumped tightly together with
5508 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
5509 * string long enough to make the total length of the two
5510 * packets constant. This should ensure that a passive
5511 * listener doing traffic analyis can't work out the length
5514 * For this to work, we need an assumption about the
5515 * maximum length of the password packet. I think 256 is
5516 * pretty conservative. Anyone using a password longer than
5517 * that probably doesn't have much to worry about from
5518 * people who find out how long their password is!
5520 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
5521 ssh2_pkt_addstring(ssh
, s
->username
);
5522 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
5523 ssh2_pkt_addstring(ssh
, "password");
5524 ssh2_pkt_addbool(ssh
, FALSE
);
5525 dont_log_password(ssh
, PKTLOG_BLANK
);
5526 ssh2_pkt_addstring(ssh
, s
->password
);
5527 memset(s
->password
, 0, sizeof(s
->password
));
5528 end_log_omission(ssh
);
5529 ssh2_pkt_defer(ssh
);
5531 * We'll include a string that's an exact multiple of the
5532 * cipher block size. If the cipher is NULL for some
5533 * reason, we don't do this trick at all because we gain
5536 if (ssh
->cscipher
) {
5539 stringlen
= (256 - ssh
->deferred_len
);
5540 stringlen
+= ssh
->cscipher
->blksize
- 1;
5541 stringlen
-= (stringlen
% ssh
->cscipher
->blksize
);
5544 * Temporarily disable actual compression,
5545 * so we can guarantee to get this string
5546 * exactly the length we want it. The
5547 * compression-disabling routine should
5548 * return an integer indicating how many
5549 * bytes we should adjust our string length
5553 ssh
->cscomp
->disable_compression(ssh
->cs_comp_ctx
);
5555 ssh2_pkt_init(ssh
, SSH2_MSG_IGNORE
);
5556 ssh2_pkt_addstring_start(ssh
);
5557 for (i
= 0; i
< stringlen
; i
++) {
5558 char c
= (char) random_byte();
5559 ssh2_pkt_addstring_data(ssh
, &c
, 1);
5561 ssh2_pkt_defer(ssh
);
5563 ssh_pkt_defersend(ssh
);
5564 logevent("Sent password");
5565 s
->type
= AUTH_TYPE_PASSWORD
;
5566 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
5567 if (s
->curr_prompt
== 0) {
5568 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_INFO_RESPONSE
);
5569 ssh2_pkt_adduint32(ssh
, s
->num_prompts
);
5571 if (s
->need_pw
) { /* only add pw if we just got one! */
5572 dont_log_password(ssh
, PKTLOG_BLANK
);
5573 ssh2_pkt_addstring(ssh
, s
->password
);
5574 memset(s
->password
, 0, sizeof(s
->password
));
5575 end_log_omission(ssh
);
5578 if (s
->curr_prompt
>= s
->num_prompts
) {
5582 * If there are prompts remaining, we set
5583 * `gotit' so that we won't attempt to get
5584 * another packet. Then we go back round the
5585 * loop and will end up retrieving another
5586 * prompt out of the existing packet. Funky or
5591 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
5593 c_write_str(ssh
, "No supported authentication methods"
5594 " left to try!\r\n");
5595 logevent("No supported authentications offered."
5597 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
5598 ssh2_pkt_adduint32(ssh
, SSH2_DISCONNECT_BY_APPLICATION
);
5599 ssh2_pkt_addstring(ssh
, "No supported authentication"
5600 " methods available");
5601 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
5603 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5607 } while (!s
->we_are_in
);
5610 * Now we're authenticated for the connection protocol. The
5611 * connection protocol will automatically have started at this
5612 * point; there's no need to send SERVICE_REQUEST.
5615 ssh
->channels
= newtree234(ssh_channelcmp
);
5618 * Create the main session channel.
5620 if (!ssh
->cfg
.ssh_no_shell
) {
5621 ssh
->mainchan
= snew(struct ssh_channel
);
5622 ssh
->mainchan
->ssh
= ssh
;
5623 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
5624 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN
);
5625 ssh2_pkt_addstring(ssh
, "session");
5626 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->localid
);
5627 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5628 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
5629 ssh2_pkt_adduint32(ssh
, 0x4000UL
); /* our max pkt size */
5631 crWaitUntilV(ispkt
);
5632 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
5633 bombout(("Server refused to open a session"));
5635 /* FIXME: error data comes back in FAILURE packet */
5637 if (ssh_pkt_getuint32(ssh
) != ssh
->mainchan
->localid
) {
5638 bombout(("Server's channel confirmation cited wrong channel"));
5641 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(ssh
);
5642 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
5643 ssh
->mainchan
->closes
= 0;
5644 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(ssh
);
5645 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(ssh
);
5646 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
5647 add234(ssh
->channels
, ssh
->mainchan
);
5648 update_specials_menu(ssh
->frontend
);
5649 logevent("Opened channel for session");
5651 ssh
->mainchan
= NULL
;
5654 * Potentially enable X11 forwarding.
5656 if (ssh
->mainchan
&& ssh
->cfg
.x11_forward
) {
5657 char proto
[20], data
[64];
5658 logevent("Requesting X11 forwarding");
5659 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
5660 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
5661 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
5662 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5663 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
5664 ssh2_pkt_addstring(ssh
, "x11-req");
5665 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5666 ssh2_pkt_addbool(ssh
, 0); /* many connections */
5667 ssh2_pkt_addstring(ssh
, proto
);
5668 ssh2_pkt_addstring(ssh
, data
);
5669 ssh2_pkt_adduint32(ssh
, x11_get_screen_number(ssh
->cfg
.x11_display
));
5673 crWaitUntilV(ispkt
);
5674 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5675 unsigned i
= ssh_pkt_getuint32(ssh
);
5676 struct ssh_channel
*c
;
5677 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5679 continue; /* nonexistent channel */
5680 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
5682 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5684 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5685 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5686 bombout(("Unexpected response to X11 forwarding request:"
5687 " packet type %d", ssh
->pktin
.type
));
5690 logevent("X11 forwarding refused");
5692 logevent("X11 forwarding enabled");
5693 ssh
->X11_fwd_enabled
= TRUE
;
5698 * Enable port forwardings.
5703 int sport
,dport
,sserv
,dserv
;
5704 char sports
[256], dports
[256], saddr
[256], host
[256];
5706 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
5707 /* Add port forwardings. */
5708 ssh
->portfwd_strptr
= ssh
->cfg
.portfwd
;
5709 while (*ssh
->portfwd_strptr
) {
5710 type
= *ssh
->portfwd_strptr
++;
5713 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= '\t') {
5714 if (*ssh
->portfwd_strptr
== ':') {
5716 * We've seen a colon in the middle of the
5717 * source port number. This means that
5718 * everything we've seen until now is the
5719 * source _address_, so we'll move it into
5720 * saddr and start sports from the beginning
5723 ssh
->portfwd_strptr
++;
5725 strcpy(saddr
, sports
);
5728 if (n
< 255) sports
[n
++] = *ssh
->portfwd_strptr
++;
5732 if (*ssh
->portfwd_strptr
== '\t')
5733 ssh
->portfwd_strptr
++;
5735 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= ':') {
5736 if (n
< 255) host
[n
++] = *ssh
->portfwd_strptr
++;
5739 if (*ssh
->portfwd_strptr
== ':')
5740 ssh
->portfwd_strptr
++;
5742 while (*ssh
->portfwd_strptr
) {
5743 if (n
< 255) dports
[n
++] = *ssh
->portfwd_strptr
++;
5746 ssh
->portfwd_strptr
++;
5747 dport
= atoi(dports
);
5751 dport
= net_service_lookup(dports
);
5753 logeventf(ssh
, "Service lookup failed for destination"
5754 " port \"%s\"", dports
);
5758 while (*ssh
->portfwd_strptr
) ssh
->portfwd_strptr
++;
5760 ssh
->portfwd_strptr
++; /* eat the NUL and move to next one */
5762 sport
= atoi(sports
);
5766 sport
= net_service_lookup(sports
);
5768 logeventf(ssh
, "Service lookup failed for source"
5769 " port \"%s\"", sports
);
5772 if (sport
&& dport
) {
5773 /* Set up a description of the source port. */
5774 static char *sportdesc
;
5775 sportdesc
= dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
5776 (int)(*saddr?
strlen(saddr
):0), *saddr?saddr
:NULL
,
5777 (int)(*saddr?
1:0), ":",
5778 (int)(sserv ?
strlen(sports
) : 0), sports
,
5779 sserv
, "(", sport
, sserv
, ")");
5781 /* Verbose description of the destination port */
5782 char *dportdesc
= dupprintf("%s:%.*s%.*s%d%.*s",
5784 (int)(dserv ?
strlen(dports
) : 0), dports
,
5785 dserv
, "(", dport
, dserv
, ")");
5786 const char *err
= pfd_addforward(host
, dport
,
5787 *saddr ? saddr
: NULL
,
5788 sport
, ssh
, &ssh
->cfg
);
5790 logeventf(ssh
, "Local port %s forward to %s"
5791 " failed: %s", sportdesc
, dportdesc
, err
);
5793 logeventf(ssh
, "Local port %s forwarding to %s",
5794 sportdesc
, dportdesc
);
5797 } else if (type
== 'D') {
5798 const char *err
= pfd_addforward(NULL
, -1,
5799 *saddr ? saddr
: NULL
,
5800 sport
, ssh
, &ssh
->cfg
);
5802 logeventf(ssh
, "Local port %s SOCKS dynamic forward"
5803 " setup failed: %s", sportdesc
, err
);
5805 logeventf(ssh
, "Local port %s doing SOCKS"
5806 " dynamic forwarding", sportdesc
);
5809 struct ssh_rportfwd
*pf
;
5810 pf
= snew(struct ssh_rportfwd
);
5811 strcpy(pf
->dhost
, host
);
5814 if (add234(ssh
->rportfwds
, pf
) != pf
) {
5815 logeventf(ssh
, "Duplicate remote port forwarding"
5816 " to %s:%d", host
, dport
);
5819 logeventf(ssh
, "Requesting remote port %s"
5820 " forward to %s:%.*s%.*s%d%.*s",
5823 (int)(dserv ?
strlen(dports
) : 0), dports
,
5824 dserv
, "(", dport
, dserv
, ")");
5825 ssh2_pkt_init(ssh
, SSH2_MSG_GLOBAL_REQUEST
);
5826 ssh2_pkt_addstring(ssh
, "tcpip-forward");
5827 ssh2_pkt_addbool(ssh
, 1);/* want reply */
5829 ssh2_pkt_addstring(ssh
, saddr
);
5830 } else if (ssh
->cfg
.rport_acceptall
) {
5831 ssh2_pkt_addstring(ssh
, "0.0.0.0");
5833 ssh2_pkt_addstring(ssh
, "127.0.0.1");
5835 ssh2_pkt_adduint32(ssh
, sport
);
5839 crWaitUntilV(ispkt
);
5840 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5841 unsigned i
= ssh_pkt_getuint32(ssh
);
5842 struct ssh_channel
*c
;
5843 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5845 continue;/* nonexistent channel */
5846 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
5848 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5850 if (ssh
->pktin
.type
!= SSH2_MSG_REQUEST_SUCCESS
) {
5851 if (ssh
->pktin
.type
!= SSH2_MSG_REQUEST_FAILURE
) {
5852 bombout(("Unexpected response to port "
5853 "forwarding request: packet type %d",
5857 logevent("Server refused this port forwarding");
5859 logevent("Remote port forwarding enabled");
5869 * Potentially enable agent forwarding.
5871 if (ssh
->mainchan
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
5872 logevent("Requesting OpenSSH-style agent forwarding");
5873 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5874 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
5875 ssh2_pkt_addstring(ssh
, "auth-agent-req@openssh.com");
5876 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5880 crWaitUntilV(ispkt
);
5881 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5882 unsigned i
= ssh_pkt_getuint32(ssh
);
5883 struct ssh_channel
*c
;
5884 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5886 continue; /* nonexistent channel */
5887 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
5889 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5891 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5892 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5893 bombout(("Unexpected response to agent forwarding request:"
5894 " packet type %d", ssh
->pktin
.type
));
5897 logevent("Agent forwarding refused");
5899 logevent("Agent forwarding enabled");
5900 ssh
->agentfwd_enabled
= TRUE
;
5905 * Now allocate a pty for the session.
5907 if (ssh
->mainchan
&& !ssh
->cfg
.nopty
) {
5908 /* Unpick the terminal-speed string. */
5909 /* XXX perhaps we should allow no speeds to be sent. */
5910 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
5911 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
5912 /* Build the pty request. */
5913 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5914 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
); /* recipient channel */
5915 ssh2_pkt_addstring(ssh
, "pty-req");
5916 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5917 ssh2_pkt_addstring(ssh
, ssh
->cfg
.termtype
);
5918 ssh2_pkt_adduint32(ssh
, ssh
->term_width
);
5919 ssh2_pkt_adduint32(ssh
, ssh
->term_height
);
5920 ssh2_pkt_adduint32(ssh
, 0); /* pixel width */
5921 ssh2_pkt_adduint32(ssh
, 0); /* pixel height */
5922 ssh2_pkt_addstring_start(ssh
);
5923 ssh2_pkt_addbyte(ssh
, 128); /* TTY_OP_ISPEED */
5924 ssh2_pkt_adduint32(ssh
, ssh
->ispeed
);
5925 ssh2_pkt_addbyte(ssh
, 129); /* TTY_OP_OSPEED */
5926 ssh2_pkt_adduint32(ssh
, ssh
->ospeed
);
5927 ssh2_pkt_addstring_data(ssh
, "\0", 1); /* TTY_OP_END */
5929 ssh
->state
= SSH_STATE_INTERMED
;
5932 crWaitUntilV(ispkt
);
5933 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5934 unsigned i
= ssh_pkt_getuint32(ssh
);
5935 struct ssh_channel
*c
;
5936 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5938 continue; /* nonexistent channel */
5939 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
5941 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5943 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5944 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5945 bombout(("Unexpected response to pty request:"
5946 " packet type %d", ssh
->pktin
.type
));
5949 c_write_str(ssh
, "Server refused to allocate pty\r\n");
5950 ssh
->editing
= ssh
->echoing
= 1;
5952 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
5953 ssh
->ospeed
, ssh
->ispeed
);
5956 ssh
->editing
= ssh
->echoing
= 1;
5960 * Send environment variables.
5962 * Simplest thing here is to send all the requests at once, and
5963 * then wait for a whole bunch of successes or failures.
5965 if (ssh
->mainchan
&& *ssh
->cfg
.environmt
) {
5966 char *e
= ssh
->cfg
.environmt
;
5967 char *var
, *varend
, *val
;
5973 while (*e
&& *e
!= '\t') e
++;
5975 if (*e
== '\t') e
++;
5980 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5981 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
5982 ssh2_pkt_addstring(ssh
, "env");
5983 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5984 ssh2_pkt_addstring_start(ssh
);
5985 ssh2_pkt_addstring_data(ssh
, var
, varend
-var
);
5986 ssh2_pkt_addstring(ssh
, val
);
5992 logeventf(ssh
, "Sent %d environment variables", s
->num_env
);
5995 s
->env_left
= s
->num_env
;
5997 while (s
->env_left
> 0) {
5999 crWaitUntilV(ispkt
);
6000 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
6001 unsigned i
= ssh_pkt_getuint32(ssh
);
6002 struct ssh_channel
*c
;
6003 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6005 continue; /* nonexistent channel */
6006 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
6008 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
6010 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6011 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6012 bombout(("Unexpected response to environment request:"
6013 " packet type %d", ssh
->pktin
.type
));
6023 if (s
->env_ok
== s
->num_env
) {
6024 logevent("All environment variables successfully set");
6025 } else if (s
->env_ok
== 0) {
6026 logevent("All environment variables refused");
6027 c_write_str(ssh
, "Server refused to set environment variables\r\n");
6029 logeventf(ssh
, "%d environment variables refused",
6030 s
->num_env
- s
->env_ok
);
6031 c_write_str(ssh
, "Server refused to set all environment variables\r\n");
6036 * Start a shell or a remote command. We may have to attempt
6037 * this twice if the config data has provided a second choice
6040 if (ssh
->mainchan
) while (1) {
6044 if (ssh
->fallback_cmd
) {
6045 subsys
= ssh
->cfg
.ssh_subsys2
;
6046 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
6048 subsys
= ssh
->cfg
.ssh_subsys
;
6049 cmd
= ssh
->cfg
.remote_cmd_ptr
;
6052 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
6053 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
); /* recipient channel */
6055 ssh2_pkt_addstring(ssh
, "subsystem");
6056 ssh2_pkt_addbool(ssh
, 1); /* want reply */
6057 ssh2_pkt_addstring(ssh
, cmd
);
6059 ssh2_pkt_addstring(ssh
, "exec");
6060 ssh2_pkt_addbool(ssh
, 1); /* want reply */
6061 ssh2_pkt_addstring(ssh
, cmd
);
6063 ssh2_pkt_addstring(ssh
, "shell");
6064 ssh2_pkt_addbool(ssh
, 1); /* want reply */
6068 crWaitUntilV(ispkt
);
6069 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
6070 unsigned i
= ssh_pkt_getuint32(ssh
);
6071 struct ssh_channel
*c
;
6072 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6074 continue; /* nonexistent channel */
6075 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
6077 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
6078 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6079 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6080 bombout(("Unexpected response to shell/command request:"
6081 " packet type %d", ssh
->pktin
.type
));
6085 * We failed to start the command. If this is the
6086 * fallback command, we really are finished; if it's
6087 * not, and if the fallback command exists, try falling
6088 * back to it before complaining.
6090 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
6091 logevent("Primary command failed; attempting fallback");
6092 ssh
->fallback_cmd
= TRUE
;
6095 bombout(("Server refused to start a shell/command"));
6098 logevent("Started a shell/command");
6103 ssh
->state
= SSH_STATE_SESSION
;
6104 if (ssh
->size_needed
)
6105 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
6106 if (ssh
->eof_needed
)
6107 ssh_special(ssh
, TS_EOF
);
6113 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
6118 s
->try_send
= FALSE
;
6120 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
6121 ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
6124 unsigned i
= ssh_pkt_getuint32(ssh
);
6125 struct ssh_channel
*c
;
6126 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6128 continue; /* nonexistent channel */
6129 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
6130 ssh_pkt_getuint32(ssh
) != SSH2_EXTENDED_DATA_STDERR
)
6131 continue; /* extended but not stderr */
6132 ssh_pkt_getstring(ssh
, &data
, &length
);
6135 c
->v
.v2
.locwindow
-= length
;
6137 case CHAN_MAINSESSION
:
6139 from_backend(ssh
->frontend
, ssh
->pktin
.type
==
6140 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
6144 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
6147 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
6150 while (length
> 0) {
6151 if (c
->u
.a
.lensofar
< 4) {
6152 int l
= min(4 - c
->u
.a
.lensofar
, length
);
6153 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
6157 c
->u
.a
.lensofar
+= l
;
6159 if (c
->u
.a
.lensofar
== 4) {
6161 4 + GET_32BIT(c
->u
.a
.msglen
);
6162 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
6164 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
6166 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
6168 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
6170 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
6174 c
->u
.a
.lensofar
+= l
;
6176 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
6179 if (agent_query(c
->u
.a
.message
,
6182 ssh_agentf_callback
, c
))
6183 ssh_agentf_callback(c
, reply
, replylen
);
6184 sfree(c
->u
.a
.message
);
6185 c
->u
.a
.lensofar
= 0;
6192 * If we are not buffering too much data,
6193 * enlarge the window again at the remote side.
6195 if (bufsize
< OUR_V2_WINSIZE
)
6196 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
6198 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
6199 unsigned i
= ssh_pkt_getuint32(ssh
);
6200 struct ssh_channel
*c
;
6202 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6204 continue; /* nonexistent channel */
6206 if (c
->type
== CHAN_X11
) {
6208 * Remote EOF on an X11 channel means we should
6209 * wrap up and close the channel ourselves.
6211 x11_close(c
->u
.x11
.s
);
6213 } else if (c
->type
== CHAN_AGENT
) {
6215 } else if (c
->type
== CHAN_SOCKDATA
) {
6216 pfd_close(c
->u
.pfd
.s
);
6219 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
6220 unsigned i
= ssh_pkt_getuint32(ssh
);
6221 struct ssh_channel
*c
;
6223 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6224 if (!c
|| ((int)c
->remoteid
) == -1) {
6225 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
6226 c ?
"half-open" : "nonexistent", i
));
6229 /* Do pre-close processing on the channel. */
6231 case CHAN_MAINSESSION
:
6232 ssh
->mainchan
= NULL
;
6233 update_specials_menu(ssh
->frontend
);
6236 if (c
->u
.x11
.s
!= NULL
)
6237 x11_close(c
->u
.x11
.s
);
6244 if (c
->u
.pfd
.s
!= NULL
)
6245 pfd_close(c
->u
.pfd
.s
);
6249 if (c
->closes
== 0) {
6250 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_CLOSE
);
6251 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
6254 del234(ssh
->channels
, c
);
6255 bufchain_clear(&c
->v
.v2
.outbuffer
);
6259 * See if that was the last channel left open.
6260 * (This is only our termination condition if we're
6261 * not running in -N mode.)
6263 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
6264 logevent("All channels closed. Disconnecting");
6267 * We used to send SSH_MSG_DISCONNECT here,
6268 * because I'd believed that _every_ conforming
6269 * SSH2 connection had to end with a disconnect
6270 * being sent by at least one side; apparently
6271 * I was wrong and it's perfectly OK to
6272 * unceremoniously slam the connection shut
6273 * when you're done, and indeed OpenSSH feels
6274 * this is more polite than sending a
6275 * DISCONNECT. So now we don't.
6277 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
6278 ssh2_pkt_adduint32(ssh
, SSH2_DISCONNECT_BY_APPLICATION
);
6279 ssh2_pkt_addstring(ssh
, "All open channels closed");
6280 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
6283 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6286 continue; /* remote sends close; ignore (FIXME) */
6287 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
6288 unsigned i
= ssh_pkt_getuint32(ssh
);
6289 struct ssh_channel
*c
;
6290 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6291 if (!c
|| c
->closes
)
6292 continue; /* nonexistent or closing channel */
6293 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
6295 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
6296 unsigned i
= ssh_pkt_getuint32(ssh
);
6297 struct ssh_channel
*c
;
6298 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6300 continue; /* nonexistent channel */
6301 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
6302 continue; /* dunno why they're confirming this */
6303 c
->remoteid
= ssh_pkt_getuint32(ssh
);
6304 c
->type
= CHAN_SOCKDATA
;
6305 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(ssh
);
6306 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(ssh
);
6308 pfd_confirm(c
->u
.pfd
.s
);
6311 * We have a pending close on this channel,
6312 * which we decided on before the server acked
6313 * the channel open. So now we know the
6314 * remoteid, we can close it again.
6316 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_CLOSE
);
6317 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
6320 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_OPEN_FAILURE
) {
6321 static const char *const reasons
[] = {
6322 "<unknown reason code>",
6323 "Administratively prohibited",
6325 "Unknown channel type",
6326 "Resource shortage",
6328 unsigned i
= ssh_pkt_getuint32(ssh
);
6329 unsigned reason_code
;
6330 char *reason_string
;
6333 struct ssh_channel
*c
;
6334 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6336 continue; /* nonexistent channel */
6337 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
6338 continue; /* dunno why they're failing this */
6340 reason_code
= ssh_pkt_getuint32(ssh
);
6341 if (reason_code
>= lenof(reasons
))
6342 reason_code
= 0; /* ensure reasons[reason_code] in range */
6343 ssh_pkt_getstring(ssh
, &reason_string
, &reason_length
);
6344 message
= dupprintf("Forwarded connection refused by"
6345 " server: %s [%.*s]", reasons
[reason_code
],
6346 reason_length
, reason_string
);
6350 pfd_close(c
->u
.pfd
.s
);
6352 del234(ssh
->channels
, c
);
6354 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
6357 int typelen
, want_reply
;
6358 int reply
= SSH2_MSG_CHANNEL_FAILURE
; /* default */
6359 struct ssh_channel
*c
;
6361 localid
= ssh_pkt_getuint32(ssh
);
6362 ssh_pkt_getstring(ssh
, &type
, &typelen
);
6363 want_reply
= ssh2_pkt_getbool(ssh
);
6366 * First, check that the channel exists. Otherwise,
6367 * we can instantly disconnect with a rude message.
6369 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
6372 sprintf(buf
, "Received channel request for nonexistent"
6373 " channel %d", localid
);
6375 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
6376 ssh2_pkt_adduint32(ssh
, SSH2_DISCONNECT_BY_APPLICATION
);
6377 ssh2_pkt_addstring(ssh
, buf
);
6378 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
6380 connection_fatal(ssh
->frontend
, "%s", buf
);
6381 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6386 * Having got the channel number, we now look at
6387 * the request type string to see if it's something
6390 if (c
== ssh
->mainchan
) {
6392 * We recognise "exit-status" and "exit-signal" on
6393 * the primary channel.
6395 if (typelen
== 11 &&
6396 !memcmp(type
, "exit-status", 11)) {
6398 ssh
->exitcode
= ssh_pkt_getuint32(ssh
);
6399 logeventf(ssh
, "Server sent command exit status %d",
6401 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
6403 } else if (typelen
== 11 &&
6404 !memcmp(type
, "exit-signal", 11)) {
6406 int is_plausible
= TRUE
, is_int
= FALSE
;
6407 char *fmt_sig
= "", *fmt_msg
= "";
6409 int msglen
= 0, core
= FALSE
;
6410 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
6411 * provide an `int' for the signal, despite its
6412 * having been a `string' in the drafts since at
6413 * least 2001. (Fixed in session.c 1.147.) Try to
6414 * infer which we can safely parse it as. */
6416 unsigned char *p
= ssh
->pktin
.body
+
6417 ssh
->pktin
.savedpos
;
6418 long len
= ssh
->pktin
.length
- ssh
->pktin
.savedpos
;
6419 unsigned long num
= GET_32BIT(p
); /* what is it? */
6420 /* If it's 0, it hardly matters; assume string */
6424 int maybe_int
= FALSE
, maybe_str
= FALSE
;
6425 #define CHECK_HYPOTHESIS(offset, result) \
6428 if (q >= 0 && q+4 <= len) { \
6429 q = q + 4 + GET_32BIT(p+q); \
6430 if (q >= 0 && q+4 <= len && \
6431 (q = q + 4 + GET_32BIT(p+q)) && q == len) \
6435 CHECK_HYPOTHESIS(4+1, maybe_int
);
6436 CHECK_HYPOTHESIS(4+num
+1, maybe_str
);
6437 #undef CHECK_HYPOTHESIS
6438 if (maybe_int
&& !maybe_str
)
6440 else if (!maybe_int
&& maybe_str
)
6443 /* Crikey. Either or neither. Panic. */
6444 is_plausible
= FALSE
;
6449 /* Old non-standard OpenSSH. */
6450 int signum
= ssh_pkt_getuint32(ssh
);
6451 fmt_sig
= dupprintf(" %d", signum
);
6453 /* As per the drafts. */
6456 ssh_pkt_getstring(ssh
, &sig
, &siglen
);
6457 /* Signal name isn't supposed to be blank, but
6458 * let's cope gracefully if it is. */
6460 fmt_sig
= dupprintf(" \"%.*s\"",
6464 core
= ssh2_pkt_getbool(ssh
);
6465 ssh_pkt_getstring(ssh
, &msg
, &msglen
);
6467 fmt_msg
= dupprintf(" (\"%.*s\")", msglen
, msg
);
6469 /* ignore lang tag */
6470 } /* else don't attempt to parse */
6471 logeventf(ssh
, "Server exited on signal%s%s%s",
6472 fmt_sig
, core ?
" (core dumped)" : "",
6474 if (*fmt_sig
) sfree(fmt_sig
);
6475 if (*fmt_msg
) sfree(fmt_msg
);
6476 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
6481 * This is a channel request we don't know
6482 * about, so we now either ignore the request
6483 * or respond with CHANNEL_FAILURE, depending
6486 reply
= SSH2_MSG_CHANNEL_FAILURE
;
6489 ssh2_pkt_init(ssh
, reply
);
6490 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
6493 } else if (ssh
->pktin
.type
== SSH2_MSG_GLOBAL_REQUEST
) {
6495 int typelen
, want_reply
;
6497 ssh_pkt_getstring(ssh
, &type
, &typelen
);
6498 want_reply
= ssh2_pkt_getbool(ssh
);
6501 * We currently don't support any global requests
6502 * at all, so we either ignore the request or
6503 * respond with REQUEST_FAILURE, depending on
6507 ssh2_pkt_init(ssh
, SSH2_MSG_REQUEST_FAILURE
);
6510 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
6517 struct ssh_channel
*c
;
6518 unsigned remid
, winsize
, pktsize
;
6519 ssh_pkt_getstring(ssh
, &type
, &typelen
);
6520 c
= snew(struct ssh_channel
);
6523 remid
= ssh_pkt_getuint32(ssh
);
6524 winsize
= ssh_pkt_getuint32(ssh
);
6525 pktsize
= ssh_pkt_getuint32(ssh
);
6527 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
6530 ssh_pkt_getstring(ssh
, &peeraddr
, &peeraddrlen
);
6531 addrstr
= snewn(peeraddrlen
+1, char);
6532 memcpy(addrstr
, peeraddr
, peeraddrlen
);
6533 addrstr
[peeraddrlen
] = '\0';
6534 peerport
= ssh_pkt_getuint32(ssh
);
6536 logeventf(ssh
, "Received X11 connect request from %s:%d",
6539 if (!ssh
->X11_fwd_enabled
)
6540 error
= "X11 forwarding is not enabled";
6541 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
6542 ssh
->x11auth
, addrstr
, peerport
,
6543 &ssh
->cfg
) != NULL
) {
6544 error
= "Unable to open an X11 connection";
6546 logevent("Opening X11 forward connection succeeded");
6551 } else if (typelen
== 15 &&
6552 !memcmp(type
, "forwarded-tcpip", 15)) {
6553 struct ssh_rportfwd pf
, *realpf
;
6556 ssh_pkt_getstring(ssh
, &dummy
, &dummylen
);/* skip address */
6557 pf
.sport
= ssh_pkt_getuint32(ssh
);
6558 ssh_pkt_getstring(ssh
, &peeraddr
, &peeraddrlen
);
6559 peerport
= ssh_pkt_getuint32(ssh
);
6560 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
6561 logeventf(ssh
, "Received remote port %d open request "
6562 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
6563 if (realpf
== NULL
) {
6564 error
= "Remote port is not recognised";
6566 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
6570 logeventf(ssh
, "Attempting to forward remote port to "
6571 "%s:%d", realpf
->dhost
, realpf
->dport
);
6573 logeventf(ssh
, "Port open failed: %s", e
);
6574 error
= "Port open failed";
6576 logevent("Forwarded port opened successfully");
6577 c
->type
= CHAN_SOCKDATA
;
6580 } else if (typelen
== 22 &&
6581 !memcmp(type
, "auth-agent@openssh.com", 3)) {
6582 if (!ssh
->agentfwd_enabled
)
6583 error
= "Agent forwarding is not enabled";
6585 c
->type
= CHAN_AGENT
; /* identify channel type */
6586 c
->u
.a
.lensofar
= 0;
6589 error
= "Unsupported channel type requested";
6592 c
->remoteid
= remid
;
6594 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN_FAILURE
);
6595 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
6596 ssh2_pkt_adduint32(ssh
, SSH2_OPEN_CONNECT_FAILED
);
6597 ssh2_pkt_addstring(ssh
, error
);
6598 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
6600 logeventf(ssh
, "Rejected channel open: %s", error
);
6603 c
->localid
= alloc_channel_id(ssh
);
6605 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6606 c
->v
.v2
.remwindow
= winsize
;
6607 c
->v
.v2
.remmaxpkt
= pktsize
;
6608 bufchain_init(&c
->v
.v2
.outbuffer
);
6609 add234(ssh
->channels
, c
);
6610 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
6611 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
6612 ssh2_pkt_adduint32(ssh
, c
->localid
);
6613 ssh2_pkt_adduint32(ssh
, c
->v
.v2
.locwindow
);
6614 ssh2_pkt_adduint32(ssh
, 0x4000UL
); /* our max pkt size */
6618 bombout(("Strange packet received: type %d", ssh
->pktin
.type
));
6621 } else if (ssh
->mainchan
) {
6623 * We have spare data. Add it to the channel buffer.
6625 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
6630 struct ssh_channel
*c
;
6632 * Try to send data on all channels if we can.
6634 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
6637 continue; /* don't send on closing channels */
6638 bufsize
= ssh2_try_send(c
);
6641 case CHAN_MAINSESSION
:
6642 /* stdin need not receive an unthrottle
6643 * notification since it will be polled */
6646 x11_unthrottle(c
->u
.x11
.s
);
6649 /* agent sockets are request/response and need no
6650 * buffer management */
6653 pfd_unthrottle(c
->u
.pfd
.s
);
6665 * Handle the top-level SSH2 protocol.
6667 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
6669 if (do_ssh2_transport(ssh
, in
, inlen
, ispkt
) == 0)
6671 do_ssh2_authconn(ssh
, in
, inlen
, ispkt
);
6675 * Called to set up the connection.
6677 * Returns an error message, or NULL on success.
6679 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
6681 char *host
, int port
, char **realhost
, int nodelay
,
6687 ssh
= snew(struct ssh_tag
);
6688 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
6689 ssh
->version
= 0; /* when not ready yet */
6692 ssh
->v1_cipher_ctx
= NULL
;
6693 ssh
->crcda_ctx
= NULL
;
6694 ssh
->cscipher
= NULL
;
6695 ssh
->cs_cipher_ctx
= NULL
;
6696 ssh
->sccipher
= NULL
;
6697 ssh
->sc_cipher_ctx
= NULL
;
6699 ssh
->cs_mac_ctx
= NULL
;
6701 ssh
->sc_mac_ctx
= NULL
;
6703 ssh
->cs_comp_ctx
= NULL
;
6705 ssh
->sc_comp_ctx
= NULL
;
6707 ssh
->kex_ctx
= NULL
;
6708 ssh
->hostkey
= NULL
;
6710 ssh
->state
= SSH_STATE_PREPACKET
;
6711 ssh
->size_needed
= FALSE
;
6712 ssh
->eof_needed
= FALSE
;
6716 static const struct Packet empty
= { 0, 0, NULL
, NULL
, 0 };
6717 ssh
->pktin
= ssh
->pktout
= empty
;
6719 ssh
->deferred_send_data
= NULL
;
6720 ssh
->deferred_len
= 0;
6721 ssh
->deferred_size
= 0;
6722 ssh
->pktout_logmode
= PKTLOG_EMIT
;
6723 ssh
->pktout_nblanks
= 0;
6724 ssh
->pktout_blanks
= NULL
;
6725 ssh
->fallback_cmd
= 0;
6727 ssh
->x11auth
= NULL
;
6728 ssh
->v1_compressing
= FALSE
;
6729 ssh
->v2_outgoing_sequence
= 0;
6730 ssh
->ssh1_rdpkt_crstate
= 0;
6731 ssh
->ssh2_rdpkt_crstate
= 0;
6732 ssh
->do_ssh_init_crstate
= 0;
6733 ssh
->ssh_gotdata_crstate
= 0;
6734 ssh
->ssh1_protocol_crstate
= 0;
6735 ssh
->do_ssh1_login_crstate
= 0;
6736 ssh
->do_ssh2_transport_crstate
= 0;
6737 ssh
->do_ssh2_authconn_crstate
= 0;
6738 ssh
->do_ssh_init_state
= NULL
;
6739 ssh
->do_ssh1_login_state
= NULL
;
6740 ssh
->do_ssh2_transport_state
= NULL
;
6741 ssh
->do_ssh2_authconn_state
= NULL
;
6742 ssh
->mainchan
= NULL
;
6743 ssh
->throttled_all
= 0;
6744 ssh
->v1_stdout_throttling
= 0;
6746 *backend_handle
= ssh
;
6749 if (crypto_startup() == 0)
6750 return "Microsoft high encryption pack not installed!";
6753 ssh
->frontend
= frontend_handle
;
6754 ssh
->term_width
= ssh
->cfg
.width
;
6755 ssh
->term_height
= ssh
->cfg
.height
;
6757 ssh
->channels
= NULL
;
6758 ssh
->rportfwds
= NULL
;
6763 ssh
->v1_throttle_count
= 0;
6764 ssh
->overall_bufsize
= 0;
6765 ssh
->fallback_cmd
= 0;
6767 ssh
->protocol
= NULL
;
6769 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
6776 static void ssh_free(void *handle
)
6778 Ssh ssh
= (Ssh
) handle
;
6779 struct ssh_channel
*c
;
6780 struct ssh_rportfwd
*pf
;
6782 if (ssh
->v1_cipher_ctx
)
6783 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
6784 if (ssh
->cs_cipher_ctx
)
6785 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
6786 if (ssh
->sc_cipher_ctx
)
6787 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
6788 if (ssh
->cs_mac_ctx
)
6789 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
6790 if (ssh
->sc_mac_ctx
)
6791 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
6792 if (ssh
->cs_comp_ctx
) {
6794 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
6796 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
6798 if (ssh
->sc_comp_ctx
) {
6800 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
6802 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
6805 dh_cleanup(ssh
->kex_ctx
);
6806 sfree(ssh
->savedhost
);
6808 if (ssh
->channels
) {
6809 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
6812 if (c
->u
.x11
.s
!= NULL
)
6813 x11_close(c
->u
.x11
.s
);
6816 if (c
->u
.pfd
.s
!= NULL
)
6817 pfd_close(c
->u
.pfd
.s
);
6822 freetree234(ssh
->channels
);
6825 if (ssh
->rportfwds
) {
6826 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
6828 freetree234(ssh
->rportfwds
);
6830 sfree(ssh
->deferred_send_data
);
6832 x11_free_auth(ssh
->x11auth
);
6833 sfree(ssh
->do_ssh_init_state
);
6834 sfree(ssh
->do_ssh1_login_state
);
6835 sfree(ssh
->do_ssh2_transport_state
);
6836 sfree(ssh
->do_ssh2_authconn_state
);
6837 if (ssh
->pktout
.data
) {
6838 sfree(ssh
->pktout
.data
);
6839 ssh
->pktout
.data
= NULL
;
6841 if (ssh
->pktin
.data
) {
6842 sfree(ssh
->pktin
.data
);
6843 ssh
->pktin
.data
= NULL
;
6845 if (ssh
->crcda_ctx
) {
6846 crcda_free_context(ssh
->crcda_ctx
);
6847 ssh
->crcda_ctx
= NULL
;
6855 * Reconfigure the SSH backend.
6857 * Currently, this function does nothing very useful. In future,
6858 * however, we could do some handy things with it. For example, we
6859 * could make the port forwarding configurer active in the Change
6860 * Settings box, and this routine could close down existing
6861 * forwardings and open up new ones in response to changes.
6863 static void ssh_reconfig(void *handle
, Config
*cfg
)
6865 Ssh ssh
= (Ssh
) handle
;
6866 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
6870 * Called to send data down the Telnet connection.
6872 static int ssh_send(void *handle
, char *buf
, int len
)
6874 Ssh ssh
= (Ssh
) handle
;
6876 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
6879 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
6881 return ssh_sendbuffer(ssh
);
6885 * Called to query the current amount of buffered stdin data.
6887 static int ssh_sendbuffer(void *handle
)
6889 Ssh ssh
= (Ssh
) handle
;
6892 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
6896 * If the SSH socket itself has backed up, add the total backup
6897 * size on that to any individual buffer on the stdin channel.
6900 if (ssh
->throttled_all
)
6901 override_value
= ssh
->overall_bufsize
;
6903 if (ssh
->version
== 1) {
6904 return override_value
;
6905 } else if (ssh
->version
== 2) {
6906 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
6907 return override_value
;
6909 return (override_value
+
6910 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
6917 * Called to set the size of the window from SSH's POV.
6919 static void ssh_size(void *handle
, int width
, int height
)
6921 Ssh ssh
= (Ssh
) handle
;
6923 ssh
->term_width
= width
;
6924 ssh
->term_height
= height
;
6926 switch (ssh
->state
) {
6927 case SSH_STATE_BEFORE_SIZE
:
6928 case SSH_STATE_PREPACKET
:
6929 case SSH_STATE_CLOSED
:
6930 break; /* do nothing */
6931 case SSH_STATE_INTERMED
:
6932 ssh
->size_needed
= TRUE
; /* buffer for later */
6934 case SSH_STATE_SESSION
:
6935 if (!ssh
->cfg
.nopty
) {
6936 if (ssh
->version
== 1) {
6937 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
6938 PKT_INT
, ssh
->term_height
,
6939 PKT_INT
, ssh
->term_width
,
6940 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
6941 } else if (ssh
->mainchan
) {
6942 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
6943 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
6944 ssh2_pkt_addstring(ssh
, "window-change");
6945 ssh2_pkt_addbool(ssh
, 0);
6946 ssh2_pkt_adduint32(ssh
, ssh
->term_width
);
6947 ssh2_pkt_adduint32(ssh
, ssh
->term_height
);
6948 ssh2_pkt_adduint32(ssh
, 0);
6949 ssh2_pkt_adduint32(ssh
, 0);
6958 * Return a list of the special codes that make sense in this
6961 static const struct telnet_special
*ssh_get_specials(void *handle
)
6963 static const struct telnet_special ignore_special
[] = {
6964 {"IGNORE message", TS_NOP
},
6966 static const struct telnet_special ssh2_session_specials
[] = {
6969 /* These are the signal names defined by draft-ietf-secsh-connect-19.
6970 * They include all the ISO C signals, but are a subset of the POSIX
6971 * required signals. */
6972 {"SIGINT (Interrupt)", TS_SIGINT
},
6973 {"SIGTERM (Terminate)", TS_SIGTERM
},
6974 {"SIGKILL (Kill)", TS_SIGKILL
},
6975 {"SIGQUIT (Quit)", TS_SIGQUIT
},
6976 {"SIGHUP (Hangup)", TS_SIGHUP
},
6977 {"More signals", TS_SUBMENU
},
6978 {"SIGABRT", TS_SIGABRT
}, {"SIGALRM", TS_SIGALRM
},
6979 {"SIGFPE", TS_SIGFPE
}, {"SIGILL", TS_SIGILL
},
6980 {"SIGPIPE", TS_SIGPIPE
}, {"SIGSEGV", TS_SIGSEGV
},
6981 {"SIGUSR1", TS_SIGUSR1
}, {"SIGUSR2", TS_SIGUSR2
},
6984 static const struct telnet_special specials_end
[] = {
6987 static struct telnet_special ssh_specials
[lenof(ignore_special
) +
6988 lenof(ssh2_session_specials
) +
6989 lenof(specials_end
)];
6990 Ssh ssh
= (Ssh
) handle
;
6992 #define ADD_SPECIALS(name) \
6994 assert((i + lenof(name)) <= lenof(ssh_specials)); \
6995 memcpy(&ssh_specials[i], name, sizeof name); \
6999 if (ssh
->version
== 1) {
7000 /* Don't bother offering IGNORE if we've decided the remote
7001 * won't cope with it, since we wouldn't bother sending it if
7003 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7004 ADD_SPECIALS(ignore_special
);
7005 } else if (ssh
->version
== 2) {
7006 /* XXX add rekey, when implemented */
7007 ADD_SPECIALS(ignore_special
);
7009 ADD_SPECIALS(ssh2_session_specials
);
7010 } /* else we're not ready yet */
7013 ADD_SPECIALS(specials_end
);
7014 return ssh_specials
;
7022 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7023 * can send an EOF and collect resulting output (e.g. `plink
7026 static void ssh_special(void *handle
, Telnet_Special code
)
7028 Ssh ssh
= (Ssh
) handle
;
7030 if (code
== TS_EOF
) {
7031 if (ssh
->state
!= SSH_STATE_SESSION
) {
7033 * Buffer the EOF in case we are pre-SESSION, so we can
7034 * send it as soon as we reach SESSION.
7037 ssh
->eof_needed
= TRUE
;
7040 if (ssh
->version
== 1) {
7041 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
7042 } else if (ssh
->mainchan
) {
7043 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_EOF
);
7044 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
7047 logevent("Sent EOF message");
7048 } else if (code
== TS_PING
|| code
== TS_NOP
) {
7049 if (ssh
->state
== SSH_STATE_CLOSED
7050 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7051 if (ssh
->version
== 1) {
7052 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7053 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
7055 ssh2_pkt_init(ssh
, SSH2_MSG_IGNORE
);
7056 ssh2_pkt_addstring_start(ssh
);
7059 } else if (code
== TS_BRK
) {
7060 if (ssh
->state
== SSH_STATE_CLOSED
7061 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7062 if (ssh
->version
== 1) {
7063 logevent("Unable to send BREAK signal in SSH1");
7064 } else if (ssh
->mainchan
) {
7065 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
7066 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
7067 ssh2_pkt_addstring(ssh
, "break");
7068 ssh2_pkt_addbool(ssh
, 0);
7069 ssh2_pkt_adduint32(ssh
, 0); /* default break length */
7073 /* Is is a POSIX signal? */
7074 char *signame
= NULL
;
7075 if (code
== TS_SIGABRT
) signame
= "ABRT";
7076 if (code
== TS_SIGALRM
) signame
= "ALRM";
7077 if (code
== TS_SIGFPE
) signame
= "FPE";
7078 if (code
== TS_SIGHUP
) signame
= "HUP";
7079 if (code
== TS_SIGILL
) signame
= "ILL";
7080 if (code
== TS_SIGINT
) signame
= "INT";
7081 if (code
== TS_SIGKILL
) signame
= "KILL";
7082 if (code
== TS_SIGPIPE
) signame
= "PIPE";
7083 if (code
== TS_SIGQUIT
) signame
= "QUIT";
7084 if (code
== TS_SIGSEGV
) signame
= "SEGV";
7085 if (code
== TS_SIGTERM
) signame
= "TERM";
7086 if (code
== TS_SIGUSR1
) signame
= "USR1";
7087 if (code
== TS_SIGUSR2
) signame
= "USR2";
7088 /* The SSH-2 protocol does in principle support arbitrary named
7089 * signals, including signame@domain, but we don't support those. */
7091 /* It's a signal. */
7092 if (ssh
->version
== 2 && ssh
->mainchan
) {
7093 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
7094 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
7095 ssh2_pkt_addstring(ssh
, "signal");
7096 ssh2_pkt_addbool(ssh
, 0);
7097 ssh2_pkt_addstring(ssh
, signame
);
7099 logeventf(ssh
, "Sent signal SIG%s", signame
);
7102 /* Never heard of it. Do nothing */
7107 void *new_sock_channel(void *handle
, Socket s
)
7109 Ssh ssh
= (Ssh
) handle
;
7110 struct ssh_channel
*c
;
7111 c
= snew(struct ssh_channel
);
7115 c
->remoteid
= -1; /* to be set when open confirmed */
7116 c
->localid
= alloc_channel_id(ssh
);
7118 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
7120 bufchain_init(&c
->v
.v2
.outbuffer
);
7121 add234(ssh
->channels
, c
);
7127 * This is called when stdout/stderr (the entity to which
7128 * from_backend sends data) manages to clear some backlog.
7130 static void ssh_unthrottle(void *handle
, int bufsize
)
7132 Ssh ssh
= (Ssh
) handle
;
7133 if (ssh
->version
== 1) {
7134 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
7135 ssh
->v1_stdout_throttling
= 0;
7136 ssh1_throttle(ssh
, -1);
7139 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
7140 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
7144 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
7146 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
7149 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
7151 if (ssh
->version
== 1) {
7152 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
7153 PKT_INT
, c
->localid
,
7156 //PKT_STR, <org:orgport>,
7159 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN
);
7160 ssh2_pkt_addstring(ssh
, "direct-tcpip");
7161 ssh2_pkt_adduint32(ssh
, c
->localid
);
7162 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7163 ssh2_pkt_adduint32(ssh
, c
->v
.v2
.locwindow
);/* our window size */
7164 ssh2_pkt_adduint32(ssh
, 0x4000UL
); /* our max pkt size */
7165 ssh2_pkt_addstring(ssh
, hostname
);
7166 ssh2_pkt_adduint32(ssh
, port
);
7168 * We make up values for the originator data; partly it's
7169 * too much hassle to keep track, and partly I'm not
7170 * convinced the server should be told details like that
7171 * about my local network configuration.
7173 ssh2_pkt_addstring(ssh
, "client-side-connection");
7174 ssh2_pkt_adduint32(ssh
, 0);
7180 static Socket
ssh_socket(void *handle
)
7182 Ssh ssh
= (Ssh
) handle
;
7186 static int ssh_sendok(void *handle
)
7188 Ssh ssh
= (Ssh
) handle
;
7189 return ssh
->send_ok
;
7192 static int ssh_ldisc(void *handle
, int option
)
7194 Ssh ssh
= (Ssh
) handle
;
7195 if (option
== LD_ECHO
)
7196 return ssh
->echoing
;
7197 if (option
== LD_EDIT
)
7198 return ssh
->editing
;
7202 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
7204 Ssh ssh
= (Ssh
) handle
;
7208 static void ssh_provide_logctx(void *handle
, void *logctx
)
7210 Ssh ssh
= (Ssh
) handle
;
7211 ssh
->logctx
= logctx
;
7214 static int ssh_return_exitcode(void *handle
)
7216 Ssh ssh
= (Ssh
) handle
;
7220 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
7224 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
7225 * that fails. This variable is the means by which scp.c can reach
7226 * into the SSH code and find out which one it got.
7228 extern int ssh_fallback_cmd(void *handle
)
7230 Ssh ssh
= (Ssh
) handle
;
7231 return ssh
->fallback_cmd
;
7234 Backend ssh_backend
= {
7244 ssh_return_exitcode
,