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 int 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
);
528 struct rdpkt1_state_tag
{
529 long len
, pad
, biglen
, to_read
;
530 unsigned long realcrc
, gotcrc
;
536 struct rdpkt2_state_tag
{
537 long len
, pad
, payload
, packetlen
, maclen
;
540 unsigned long incoming_sequence
;
544 const struct plug_function_table
*fn
;
545 /* the above field _must_ be first in the structure */
547 SHA_State exhash
, exhashbase
;
554 unsigned char session_key
[32];
556 int v1_remote_protoflags
;
557 int v1_local_protoflags
;
558 int agentfwd_enabled
;
561 const struct ssh_cipher
*cipher
;
564 const struct ssh2_cipher
*cscipher
, *sccipher
;
565 void *cs_cipher_ctx
, *sc_cipher_ctx
;
566 const struct ssh_mac
*csmac
, *scmac
;
567 void *cs_mac_ctx
, *sc_mac_ctx
;
568 const struct ssh_compress
*cscomp
, *sccomp
;
569 void *cs_comp_ctx
, *sc_comp_ctx
;
570 const struct ssh_kex
*kex
;
571 const struct ssh_signkey
*hostkey
;
572 unsigned char v2_session_id
[20];
578 int echoing
, editing
;
582 int ospeed
, ispeed
; /* temporaries */
583 int term_width
, term_height
;
585 tree234
*channels
; /* indexed by local id */
586 struct ssh_channel
*mainchan
; /* primary session channel */
593 SSH_STATE_BEFORE_SIZE
,
599 int size_needed
, eof_needed
;
602 struct Packet pktout
;
603 unsigned char *deferred_send_data
;
604 int deferred_len
, deferred_size
;
607 * State associated with packet logging
611 struct logblank_t
*pktout_blanks
;
614 * Gross hack: pscp will try to start SFTP but fall back to
615 * scp1 if that fails. This variable is the means by which
616 * scp.c can reach into the SSH code and find out which one it
622 * Used for username and password input.
624 char *userpass_input_buffer
;
625 int userpass_input_buflen
;
626 int userpass_input_bufpos
;
627 int userpass_input_echo
;
629 char *portfwd_strptr
;
635 int v1_throttle_count
;
638 int v1_stdout_throttling
;
639 int v2_outgoing_sequence
;
641 int ssh1_rdpkt_crstate
;
642 int ssh2_rdpkt_crstate
;
643 int do_ssh_init_crstate
;
644 int ssh_gotdata_crstate
;
645 int ssh1_protocol_crstate
;
646 int do_ssh1_login_crstate
;
647 int do_ssh2_transport_crstate
;
648 int do_ssh2_authconn_crstate
;
650 void *do_ssh_init_state
;
651 void *do_ssh1_login_state
;
652 void *do_ssh2_transport_state
;
653 void *do_ssh2_authconn_state
;
655 struct rdpkt1_state_tag rdpkt1_state
;
656 struct rdpkt2_state_tag rdpkt2_state
;
658 void (*protocol
) (Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
659 int (*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
662 * We maintain a full _copy_ of a Config structure here, not
663 * merely a pointer to it. That way, when we're passed a new
664 * one for reconfiguration, we can check the differences and
665 * potentially reconfigure port forwardings etc in mid-session.
670 * Used to transfer data back from async agent callbacks.
672 void *agent_response
;
673 int agent_response_len
;
676 #define logevent(s) logevent(ssh->frontend, s)
678 /* logevent, only printf-formatted. */
679 static void logeventf(Ssh ssh
, const char *fmt
, ...)
685 buf
= dupvprintf(fmt
, ap
);
691 #define bombout(msg) \
693 char *text = dupprintf msg; \
696 connection_fatal(ssh->frontend, "%s", text); \
700 /* Functions to leave bits out of the SSH packet log file. */
702 static void dont_log_password(Ssh ssh
, int blanktype
)
704 if (ssh
->cfg
.logomitpass
)
705 ssh
->pktout_logmode
= blanktype
;
708 static void dont_log_data(Ssh ssh
, int blanktype
)
710 if (ssh
->cfg
.logomitdata
)
711 ssh
->pktout_logmode
= blanktype
;
714 static void end_log_omission(Ssh ssh
)
716 ssh
->pktout_logmode
= PKTLOG_EMIT
;
719 static int ssh_channelcmp(void *av
, void *bv
)
721 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
722 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
723 if (a
->localid
< b
->localid
)
725 if (a
->localid
> b
->localid
)
729 static int ssh_channelfind(void *av
, void *bv
)
731 unsigned *a
= (unsigned *) av
;
732 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
740 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
742 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
743 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
745 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
746 return i
< 0 ?
-1 : +1;
747 if (a
->dport
> b
->dport
)
749 if (a
->dport
< b
->dport
)
754 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
756 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
757 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
759 if (a
->sport
> b
->sport
)
761 if (a
->sport
< b
->sport
)
766 static int alloc_channel_id(Ssh ssh
)
768 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
769 unsigned low
, high
, mid
;
771 struct ssh_channel
*c
;
774 * First-fit allocation of channel numbers: always pick the
775 * lowest unused one. To do this, binary-search using the
776 * counted B-tree to find the largest channel ID which is in a
777 * contiguous sequence from the beginning. (Precisely
778 * everything in that sequence must have ID equal to its tree
779 * index plus CHANNEL_NUMBER_OFFSET.)
781 tsize
= count234(ssh
->channels
);
785 while (high
- low
> 1) {
786 mid
= (high
+ low
) / 2;
787 c
= index234(ssh
->channels
, mid
);
788 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
789 low
= mid
; /* this one is fine */
791 high
= mid
; /* this one is past it */
794 * Now low points to either -1, or the tree index of the
795 * largest ID in the initial sequence.
798 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
799 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
801 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
804 static void c_write(Ssh ssh
, const char *buf
, int len
)
806 if ((flags
& FLAG_STDERR
)) {
808 for (i
= 0; i
< len
; i
++)
810 fputc(buf
[i
], stderr
);
813 from_backend(ssh
->frontend
, 1, buf
, len
);
816 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
819 for (i
= 0; i
< len
; i
++) {
821 c_write(ssh
, "\r\n", 2);
822 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
823 c_write(ssh
, buf
+ i
, 1);
827 static void c_write_str(Ssh ssh
, const char *buf
)
829 c_write(ssh
, buf
, strlen(buf
));
833 * Collect incoming data in the incoming packet buffer.
834 * Decipher and verify the packet when it is completely read.
835 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
836 * Update the *data and *datalen variables.
837 * Return the additional nr of bytes needed, or 0 when
838 * a complete packet is available.
840 static int ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
842 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
844 crBegin(ssh
->ssh1_rdpkt_crstate
);
849 ssh
->pktin
.length
= 0;
851 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
852 while ((*datalen
) == 0)
854 st
->len
= (st
->len
<< 8) + **data
;
855 (*data
)++, (*datalen
)--;
858 st
->pad
= 8 - (st
->len
% 8);
859 st
->biglen
= st
->len
+ st
->pad
;
860 ssh
->pktin
.length
= st
->len
- 5;
862 if (st
->biglen
< 0) {
863 bombout(("Extremely large packet length from server suggests"
864 " data stream corruption"));
868 if (ssh
->pktin
.maxlen
< st
->biglen
) {
869 ssh
->pktin
.maxlen
= st
->biglen
;
870 ssh
->pktin
.data
= sresize(ssh
->pktin
.data
, st
->biglen
+ APIEXTRA
,
874 st
->to_read
= st
->biglen
;
875 st
->p
= ssh
->pktin
.data
;
876 while (st
->to_read
> 0) {
877 st
->chunk
= st
->to_read
;
878 while ((*datalen
) == 0)
879 crReturn(st
->to_read
);
880 if (st
->chunk
> (*datalen
))
881 st
->chunk
= (*datalen
);
882 memcpy(st
->p
, *data
, st
->chunk
);
884 *datalen
-= st
->chunk
;
886 st
->to_read
-= st
->chunk
;
889 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, ssh
->pktin
.data
,
891 bombout(("Network attack (CRC compensation) detected!"));
896 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, ssh
->pktin
.data
, st
->biglen
);
898 st
->realcrc
= crc32_compute(ssh
->pktin
.data
, st
->biglen
- 4);
899 st
->gotcrc
= GET_32BIT(ssh
->pktin
.data
+ st
->biglen
- 4);
900 if (st
->gotcrc
!= st
->realcrc
) {
901 bombout(("Incorrect CRC received on packet"));
905 ssh
->pktin
.body
= ssh
->pktin
.data
+ st
->pad
+ 1;
906 ssh
->pktin
.savedpos
= 0;
908 if (ssh
->v1_compressing
) {
909 unsigned char *decompblk
;
911 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
912 ssh
->pktin
.body
- 1, ssh
->pktin
.length
+ 1,
913 &decompblk
, &decomplen
)) {
914 bombout(("Zlib decompression encountered invalid data"));
918 if (ssh
->pktin
.maxlen
< st
->pad
+ decomplen
) {
919 ssh
->pktin
.maxlen
= st
->pad
+ decomplen
;
920 ssh
->pktin
.data
= sresize(ssh
->pktin
.data
,
921 ssh
->pktin
.maxlen
+ APIEXTRA
,
923 ssh
->pktin
.body
= ssh
->pktin
.data
+ st
->pad
+ 1;
926 memcpy(ssh
->pktin
.body
- 1, decompblk
, decomplen
);
928 ssh
->pktin
.length
= decomplen
- 1;
931 ssh
->pktin
.type
= ssh
->pktin
.body
[-1];
934 * Log incoming packet, possibly omitting sensitive fields.
938 struct logblank_t blank
;
939 if (ssh
->cfg
.logomitdata
) {
940 int do_blank
= FALSE
, blank_prefix
= 0;
941 /* "Session data" packets - omit the data field */
942 if ((ssh
->pktin
.type
== SSH1_SMSG_STDOUT_DATA
) ||
943 (ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
)) {
944 do_blank
= TRUE
; blank_prefix
= 0;
945 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
946 do_blank
= TRUE
; blank_prefix
= 4;
949 blank
.offset
= blank_prefix
;
950 blank
.len
= ssh
->pktin
.length
;
951 blank
.type
= PKTLOG_OMIT
;
955 log_packet(ssh
->logctx
,
956 PKT_INCOMING
, ssh
->pktin
.type
,
957 ssh1_pkt_type(ssh
->pktin
.type
),
958 ssh
->pktin
.body
, ssh
->pktin
.length
,
962 if (ssh
->pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
963 ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
||
964 ssh
->pktin
.type
== SSH1_MSG_DEBUG
||
965 ssh
->pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
966 ssh
->pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
967 long stringlen
= GET_32BIT(ssh
->pktin
.body
);
968 if (stringlen
+ 4 != ssh
->pktin
.length
) {
969 bombout(("Received data packet with bogus string length"));
974 if (ssh
->pktin
.type
== SSH1_MSG_DEBUG
) {
975 /* log debug message */
977 int stringlen
= GET_32BIT(ssh
->pktin
.body
);
978 strcpy(buf
, "Remote debug message: ");
981 memcpy(buf
+ 8, ssh
->pktin
.body
+ 4, stringlen
);
982 buf
[8 + stringlen
] = '\0';
985 } else if (ssh
->pktin
.type
== SSH1_MSG_IGNORE
) {
990 if (ssh
->pktin
.type
== SSH1_MSG_DISCONNECT
) {
991 /* log reason code in disconnect message */
993 unsigned msglen
= GET_32BIT(ssh
->pktin
.body
);
995 strcpy(buf
, "Remote sent disconnect: ");
996 nowlen
= strlen(buf
);
997 if (msglen
> sizeof(buf
) - nowlen
- 1)
998 msglen
= sizeof(buf
) - nowlen
- 1;
999 memcpy(buf
+ nowlen
, ssh
->pktin
.body
+ 4, msglen
);
1000 buf
[nowlen
+ msglen
] = '\0';
1001 /* logevent(buf); (this is now done within the bombout macro) */
1002 bombout(("Server sent disconnect message:\n\"%s\"", buf
+nowlen
));
1009 static int ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1011 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1013 crBegin(ssh
->ssh2_rdpkt_crstate
);
1016 ssh
->pktin
.type
= 0;
1017 ssh
->pktin
.length
= 0;
1019 st
->cipherblk
= ssh
->sccipher
->blksize
;
1022 if (st
->cipherblk
< 8)
1025 if (ssh
->pktin
.maxlen
< st
->cipherblk
) {
1026 ssh
->pktin
.maxlen
= st
->cipherblk
;
1027 ssh
->pktin
.data
= sresize(ssh
->pktin
.data
, st
->cipherblk
+ APIEXTRA
,
1032 * Acquire and decrypt the first block of the packet. This will
1033 * contain the length and padding details.
1035 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1036 while ((*datalen
) == 0)
1037 crReturn(st
->cipherblk
- st
->i
);
1038 ssh
->pktin
.data
[st
->i
] = *(*data
)++;
1043 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1044 ssh
->pktin
.data
, st
->cipherblk
);
1047 * Now get the length and padding figures.
1049 st
->len
= GET_32BIT(ssh
->pktin
.data
);
1050 st
->pad
= ssh
->pktin
.data
[4];
1053 * _Completely_ silly lengths should be stomped on before they
1054 * do us any more damage.
1056 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
1057 bombout(("Incoming packet was garbled on decryption"));
1062 * This enables us to deduce the payload length.
1064 st
->payload
= st
->len
- st
->pad
- 1;
1066 ssh
->pktin
.length
= st
->payload
+ 5;
1069 * So now we can work out the total packet length.
1071 st
->packetlen
= st
->len
+ 4;
1072 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1075 * Adjust memory allocation if packet is too big.
1077 if (ssh
->pktin
.maxlen
< st
->packetlen
+ st
->maclen
) {
1078 ssh
->pktin
.maxlen
= st
->packetlen
+ st
->maclen
;
1079 ssh
->pktin
.data
= sresize(ssh
->pktin
.data
,
1080 ssh
->pktin
.maxlen
+ APIEXTRA
,
1085 * Read and decrypt the remainder of the packet.
1087 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1089 while ((*datalen
) == 0)
1090 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
1091 ssh
->pktin
.data
[st
->i
] = *(*data
)++;
1094 /* Decrypt everything _except_ the MAC. */
1096 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1097 ssh
->pktin
.data
+ st
->cipherblk
,
1098 st
->packetlen
- st
->cipherblk
);
1104 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, ssh
->pktin
.data
, st
->len
+ 4,
1105 st
->incoming_sequence
)) {
1106 bombout(("Incorrect MAC received on packet"));
1109 st
->incoming_sequence
++; /* whether or not we MACed */
1112 * Decompress packet payload.
1115 unsigned char *newpayload
;
1118 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1119 ssh
->pktin
.data
+ 5, ssh
->pktin
.length
- 5,
1120 &newpayload
, &newlen
)) {
1121 if (ssh
->pktin
.maxlen
< newlen
+ 5) {
1122 ssh
->pktin
.maxlen
= newlen
+ 5;
1123 ssh
->pktin
.data
= sresize(ssh
->pktin
.data
,
1124 ssh
->pktin
.maxlen
+ APIEXTRA
,
1127 ssh
->pktin
.length
= 5 + newlen
;
1128 memcpy(ssh
->pktin
.data
+ 5, newpayload
, newlen
);
1133 ssh
->pktin
.savedpos
= 6;
1134 ssh
->pktin
.body
= ssh
->pktin
.data
;
1135 ssh
->pktin
.type
= ssh
->pktin
.data
[5];
1138 * Log incoming packet, possibly omitting sensitive fields.
1142 struct logblank_t blank
;
1143 if (ssh
->cfg
.logomitdata
) {
1144 int do_blank
= FALSE
, blank_prefix
= 0;
1145 /* "Session data" packets - omit the data field */
1146 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_DATA
) {
1147 do_blank
= TRUE
; blank_prefix
= 4;
1148 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1149 do_blank
= TRUE
; blank_prefix
= 8;
1152 blank
.offset
= blank_prefix
;
1153 blank
.len
= (ssh
->pktin
.length
-6) - blank_prefix
;
1154 blank
.type
= PKTLOG_OMIT
;
1158 log_packet(ssh
->logctx
, PKT_INCOMING
, ssh
->pktin
.type
,
1159 ssh2_pkt_type(ssh
->pkt_ctx
, ssh
->pktin
.type
),
1160 ssh
->pktin
.data
+6, ssh
->pktin
.length
-6,
1164 switch (ssh
->pktin
.type
) {
1166 * These packets we must handle instantly.
1168 case SSH2_MSG_DISCONNECT
:
1170 /* log reason code in disconnect message */
1173 int reason
= GET_32BIT(ssh
->pktin
.data
+ 6);
1174 unsigned msglen
= GET_32BIT(ssh
->pktin
.data
+ 10);
1176 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
1177 buf
= dupprintf("Received disconnect message (%s)",
1178 ssh2_disconnect_reasons
[reason
]);
1180 buf
= dupprintf("Received disconnect message (unknown"
1181 " type %d)", reason
);
1185 buf
= dupprintf("Disconnection message text: %n%.*s",
1186 &nowlen
, msglen
, ssh
->pktin
.data
+ 14);
1188 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
1190 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
1191 ssh2_disconnect_reasons
[reason
] : "unknown",
1197 case SSH2_MSG_IGNORE
:
1199 case SSH2_MSG_DEBUG
:
1201 /* log the debug message */
1203 /* int display = ssh->pktin.body[6]; */
1204 int stringlen
= GET_32BIT(ssh
->pktin
.data
+7);
1206 strcpy(buf
, "Remote debug message: ");
1207 prefix
= strlen(buf
);
1208 if (stringlen
> (int)(sizeof(buf
)-prefix
-1))
1209 stringlen
= sizeof(buf
)-prefix
-1;
1210 memcpy(buf
+ prefix
, ssh
->pktin
.data
+ 11, stringlen
);
1211 buf
[prefix
+ stringlen
] = '\0';
1214 goto next_packet
; /* FIXME: print the debug message */
1217 * These packets we need do nothing about here.
1219 case SSH2_MSG_UNIMPLEMENTED
:
1220 case SSH2_MSG_SERVICE_REQUEST
:
1221 case SSH2_MSG_SERVICE_ACCEPT
:
1222 case SSH2_MSG_KEXINIT
:
1223 case SSH2_MSG_NEWKEYS
:
1224 case SSH2_MSG_KEXDH_INIT
:
1225 case SSH2_MSG_KEXDH_REPLY
:
1226 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1227 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1228 case SSH2_MSG_KEX_DH_GEX_INIT
:
1229 case SSH2_MSG_KEX_DH_GEX_REPLY
:
1230 case SSH2_MSG_USERAUTH_REQUEST
:
1231 case SSH2_MSG_USERAUTH_FAILURE
:
1232 case SSH2_MSG_USERAUTH_SUCCESS
:
1233 case SSH2_MSG_USERAUTH_BANNER
:
1234 case SSH2_MSG_USERAUTH_PK_OK
:
1235 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1236 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1237 case SSH2_MSG_USERAUTH_INFO_RESPONSE
:
1238 case SSH2_MSG_GLOBAL_REQUEST
:
1239 case SSH2_MSG_REQUEST_SUCCESS
:
1240 case SSH2_MSG_REQUEST_FAILURE
:
1241 case SSH2_MSG_CHANNEL_OPEN
:
1242 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
:
1243 case SSH2_MSG_CHANNEL_OPEN_FAILURE
:
1244 case SSH2_MSG_CHANNEL_WINDOW_ADJUST
:
1245 case SSH2_MSG_CHANNEL_DATA
:
1246 case SSH2_MSG_CHANNEL_EXTENDED_DATA
:
1247 case SSH2_MSG_CHANNEL_EOF
:
1248 case SSH2_MSG_CHANNEL_CLOSE
:
1249 case SSH2_MSG_CHANNEL_REQUEST
:
1250 case SSH2_MSG_CHANNEL_SUCCESS
:
1251 case SSH2_MSG_CHANNEL_FAILURE
:
1255 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1258 ssh2_pkt_init(ssh
, SSH2_MSG_UNIMPLEMENTED
);
1259 ssh2_pkt_adduint32(ssh
, st
->incoming_sequence
- 1);
1267 static void ssh1_pktout_size(Ssh ssh
, int len
)
1271 len
+= 5; /* type and CRC */
1272 pad
= 8 - (len
% 8);
1275 ssh
->pktout
.length
= len
- 5;
1276 if (ssh
->pktout
.maxlen
< biglen
) {
1277 ssh
->pktout
.maxlen
= biglen
;
1279 /* Allocate enough buffer space for extra block
1280 * for MS CryptEncrypt() */
1281 ssh
->pktout
.data
= sresize(ssh
->pktout
.data
, biglen
+ 12,
1284 ssh
->pktout
.data
= sresize(ssh
->pktout
.data
, biglen
+ 4,
1288 ssh
->pktout
.body
= ssh
->pktout
.data
+ 4 + pad
+ 1;
1291 static void s_wrpkt_start(Ssh ssh
, int type
, int len
)
1293 ssh1_pktout_size(ssh
, len
);
1294 ssh
->pktout
.type
= type
;
1295 /* Initialise log omission state */
1296 ssh
->pktout_nblanks
= 0;
1297 ssh
->pktout_blanks
= NULL
;
1300 static int s_wrpkt_prepare(Ssh ssh
)
1306 * XXX various versions of SC (including 8.8.4) screw up the
1307 * register allocation in this function and use the same register
1308 * (D6) for len and as a temporary, with predictable results. The
1309 * following sledgehammer prevents this.
1315 ssh
->pktout
.body
[-1] = ssh
->pktout
.type
;
1318 log_packet(ssh
->logctx
, PKT_OUTGOING
, ssh
->pktout
.type
,
1319 ssh1_pkt_type(ssh
->pktout
.type
),
1320 ssh
->pktout
.body
, ssh
->pktout
.length
,
1321 ssh
->pktout_nblanks
, ssh
->pktout_blanks
);
1322 sfree(ssh
->pktout_blanks
); ssh
->pktout_blanks
= NULL
;
1323 ssh
->pktout_nblanks
= 0;
1325 if (ssh
->v1_compressing
) {
1326 unsigned char *compblk
;
1328 zlib_compress_block(ssh
->cs_comp_ctx
,
1329 ssh
->pktout
.body
- 1, ssh
->pktout
.length
+ 1,
1330 &compblk
, &complen
);
1331 ssh1_pktout_size(ssh
, complen
- 1);
1332 memcpy(ssh
->pktout
.body
- 1, compblk
, complen
);
1336 len
= ssh
->pktout
.length
+ 5; /* type and CRC */
1337 pad
= 8 - (len
% 8);
1340 for (i
= 0; i
< pad
; i
++)
1341 ssh
->pktout
.data
[i
+ 4] = random_byte();
1342 crc
= crc32_compute(ssh
->pktout
.data
+ 4, biglen
- 4);
1343 PUT_32BIT(ssh
->pktout
.data
+ biglen
, crc
);
1344 PUT_32BIT(ssh
->pktout
.data
, len
);
1347 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, ssh
->pktout
.data
+ 4, biglen
);
1352 static void s_wrpkt(Ssh ssh
)
1355 len
= s_wrpkt_prepare(ssh
);
1356 backlog
= sk_write(ssh
->s
, (char *)ssh
->pktout
.data
, len
);
1357 if (backlog
> SSH_MAX_BACKLOG
)
1358 ssh_throttle_all(ssh
, 1, backlog
);
1361 static void s_wrpkt_defer(Ssh ssh
)
1364 len
= s_wrpkt_prepare(ssh
);
1365 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1366 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1367 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1371 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, ssh
->pktout
.data
, len
);
1372 ssh
->deferred_len
+= len
;
1376 * Construct a packet with the specified contents.
1378 static void construct_packet(Ssh ssh
, int pkttype
, va_list ap1
, va_list ap2
)
1380 unsigned char *p
, *argp
, argchar
;
1381 unsigned long argint
;
1382 int pktlen
, argtype
, arglen
;
1386 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1389 (void) va_arg(ap1
, int);
1393 (void) va_arg(ap1
, int);
1397 (void) va_arg(ap1
, unsigned char *);
1398 arglen
= va_arg(ap1
, int);
1402 argp
= va_arg(ap1
, unsigned char *);
1403 arglen
= strlen((char *)argp
);
1404 pktlen
+= 4 + arglen
;
1407 bn
= va_arg(ap1
, Bignum
);
1408 pktlen
+= ssh1_bignum_length(bn
);
1413 /* ignore this pass */
1420 s_wrpkt_start(ssh
, pkttype
, pktlen
);
1421 p
= ssh
->pktout
.body
;
1423 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1424 int offset
= p
- ssh
->pktout
.body
, len
= 0;
1426 /* Actual fields in the packet */
1428 argint
= va_arg(ap2
, int);
1429 PUT_32BIT(p
, argint
);
1433 argchar
= (unsigned char) va_arg(ap2
, int);
1438 argp
= va_arg(ap2
, unsigned char *);
1439 arglen
= va_arg(ap2
, int);
1440 memcpy(p
, argp
, arglen
);
1444 argp
= va_arg(ap2
, unsigned char *);
1445 arglen
= strlen((char *)argp
);
1446 PUT_32BIT(p
, arglen
);
1447 memcpy(p
+ 4, argp
, arglen
);
1451 bn
= va_arg(ap2
, Bignum
);
1452 len
= ssh1_write_bignum(p
, bn
);
1454 /* Tokens for modifications to packet logging */
1456 dont_log_password(ssh
, PKTLOG_BLANK
);
1459 dont_log_data(ssh
, PKTLOG_OMIT
);
1462 end_log_omission(ssh
);
1466 /* Deal with logfile omission, if required. */
1467 if (len
&& (ssh
->pktout_logmode
!= PKTLOG_EMIT
)) {
1468 ssh
->pktout_nblanks
++;
1469 ssh
->pktout_blanks
= sresize(ssh
->pktout_blanks
,
1470 ssh
->pktout_nblanks
,
1472 ssh
->pktout_blanks
[ssh
->pktout_nblanks
-1].offset
= offset
;
1473 ssh
->pktout_blanks
[ssh
->pktout_nblanks
-1].len
= len
;
1474 ssh
->pktout_blanks
[ssh
->pktout_nblanks
-1].type
=
1475 ssh
->pktout_logmode
;
1480 static void send_packet(Ssh ssh
, int pkttype
, ...)
1483 va_start(ap1
, pkttype
);
1484 va_start(ap2
, pkttype
);
1485 construct_packet(ssh
, pkttype
, ap1
, ap2
);
1489 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1492 va_start(ap1
, pkttype
);
1493 va_start(ap2
, pkttype
);
1494 construct_packet(ssh
, pkttype
, ap1
, ap2
);
1498 static int ssh_versioncmp(char *a
, char *b
)
1501 unsigned long av
, bv
;
1503 av
= strtoul(a
, &ae
, 10);
1504 bv
= strtoul(b
, &be
, 10);
1506 return (av
< bv ?
-1 : +1);
1511 av
= strtoul(ae
, &ae
, 10);
1512 bv
= strtoul(be
, &be
, 10);
1514 return (av
< bv ?
-1 : +1);
1519 * Utility routines for putting an SSH-protocol `string' and
1520 * `uint32' into a SHA state.
1523 static void sha_string(SHA_State
* s
, void *str
, int len
)
1525 unsigned char lenblk
[4];
1526 PUT_32BIT(lenblk
, len
);
1527 SHA_Bytes(s
, lenblk
, 4);
1528 SHA_Bytes(s
, str
, len
);
1531 static void sha_uint32(SHA_State
* s
, unsigned i
)
1533 unsigned char intblk
[4];
1534 PUT_32BIT(intblk
, i
);
1535 SHA_Bytes(s
, intblk
, 4);
1539 * SSH2 packet construction functions.
1541 static void ssh2_pkt_ensure(Ssh ssh
, int length
)
1543 if (ssh
->pktout
.maxlen
< length
) {
1544 ssh
->pktout
.maxlen
= length
+ 256;
1545 ssh
->pktout
.data
= sresize(ssh
->pktout
.data
,
1546 ssh
->pktout
.maxlen
+ APIEXTRA
,
1548 if (!ssh
->pktout
.data
)
1549 fatalbox("Out of memory");
1552 static void ssh2_pkt_adddata(Ssh ssh
, void *data
, int len
)
1554 if (ssh
->pktout_logmode
!= PKTLOG_EMIT
) {
1555 ssh
->pktout_nblanks
++;
1556 ssh
->pktout_blanks
= sresize(ssh
->pktout_blanks
, ssh
->pktout_nblanks
,
1558 ssh
->pktout_blanks
[ssh
->pktout_nblanks
-1].offset
=
1559 ssh
->pktout
.length
- 6;
1560 ssh
->pktout_blanks
[ssh
->pktout_nblanks
-1].len
= len
;
1561 ssh
->pktout_blanks
[ssh
->pktout_nblanks
-1].type
= ssh
->pktout_logmode
;
1563 ssh
->pktout
.length
+= len
;
1564 ssh2_pkt_ensure(ssh
, ssh
->pktout
.length
);
1565 memcpy(ssh
->pktout
.data
+ ssh
->pktout
.length
- len
, data
, len
);
1567 static void ssh2_pkt_addbyte(Ssh ssh
, unsigned char byte
)
1569 ssh2_pkt_adddata(ssh
, &byte
, 1);
1571 static void ssh2_pkt_init(Ssh ssh
, int pkt_type
)
1573 ssh
->pktout
.length
= 5;
1574 ssh
->pktout_nblanks
= 0; ssh
->pktout_blanks
= NULL
;
1575 ssh2_pkt_addbyte(ssh
, (unsigned char) pkt_type
);
1577 static void ssh2_pkt_addbool(Ssh ssh
, unsigned char value
)
1579 ssh2_pkt_adddata(ssh
, &value
, 1);
1581 static void ssh2_pkt_adduint32(Ssh ssh
, unsigned long value
)
1584 PUT_32BIT(x
, value
);
1585 ssh2_pkt_adddata(ssh
, x
, 4);
1587 static void ssh2_pkt_addstring_start(Ssh ssh
)
1589 ssh2_pkt_adduint32(ssh
, 0);
1590 ssh
->pktout
.savedpos
= ssh
->pktout
.length
;
1592 static void ssh2_pkt_addstring_str(Ssh ssh
, char *data
)
1594 ssh2_pkt_adddata(ssh
, data
, strlen(data
));
1595 PUT_32BIT(ssh
->pktout
.data
+ ssh
->pktout
.savedpos
- 4,
1596 ssh
->pktout
.length
- ssh
->pktout
.savedpos
);
1598 static void ssh2_pkt_addstring_data(Ssh ssh
, char *data
, int len
)
1600 ssh2_pkt_adddata(ssh
, data
, len
);
1601 PUT_32BIT(ssh
->pktout
.data
+ ssh
->pktout
.savedpos
- 4,
1602 ssh
->pktout
.length
- ssh
->pktout
.savedpos
);
1604 static void ssh2_pkt_addstring(Ssh ssh
, char *data
)
1606 ssh2_pkt_addstring_start(ssh
);
1607 ssh2_pkt_addstring_str(ssh
, data
);
1609 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1612 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1613 p
= snewn(n
+ 1, unsigned char);
1615 fatalbox("out of memory");
1617 for (i
= 1; i
<= n
; i
++)
1618 p
[i
] = bignum_byte(b
, n
- i
);
1620 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1622 memmove(p
, p
+ i
, n
+ 1 - i
);
1626 static void ssh2_pkt_addmp(Ssh ssh
, Bignum b
)
1630 p
= ssh2_mpint_fmt(b
, &len
);
1631 ssh2_pkt_addstring_start(ssh
);
1632 ssh2_pkt_addstring_data(ssh
, (char *)p
, len
);
1637 * Construct an SSH2 final-form packet: compress it, encrypt it,
1638 * put the MAC on it. Final packet, ready to be sent, is stored in
1639 * ssh->pktout.data. Total length is returned.
1641 static int ssh2_pkt_construct(Ssh ssh
)
1643 int cipherblk
, maclen
, padding
, i
;
1646 log_packet(ssh
->logctx
, PKT_OUTGOING
, ssh
->pktout
.data
[5],
1647 ssh2_pkt_type(ssh
->pkt_ctx
, ssh
->pktout
.data
[5]),
1648 ssh
->pktout
.data
+ 6, ssh
->pktout
.length
- 6,
1649 ssh
->pktout_nblanks
, ssh
->pktout_blanks
);
1650 sfree(ssh
->pktout_blanks
); ssh
->pktout_blanks
= NULL
;
1651 ssh
->pktout_nblanks
= 0;
1654 * Compress packet payload.
1657 unsigned char *newpayload
;
1660 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, ssh
->pktout
.data
+ 5,
1661 ssh
->pktout
.length
- 5,
1662 &newpayload
, &newlen
)) {
1663 ssh
->pktout
.length
= 5;
1664 ssh2_pkt_adddata(ssh
, newpayload
, newlen
);
1670 * Add padding. At least four bytes, and must also bring total
1671 * length (minus MAC) up to a multiple of the block size.
1673 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1674 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1677 (cipherblk
- (ssh
->pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
1678 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1679 ssh2_pkt_ensure(ssh
, ssh
->pktout
.length
+ padding
+ maclen
);
1680 ssh
->pktout
.data
[4] = padding
;
1681 for (i
= 0; i
< padding
; i
++)
1682 ssh
->pktout
.data
[ssh
->pktout
.length
+ i
] = random_byte();
1683 PUT_32BIT(ssh
->pktout
.data
, ssh
->pktout
.length
+ padding
- 4);
1685 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, ssh
->pktout
.data
,
1686 ssh
->pktout
.length
+ padding
,
1687 ssh
->v2_outgoing_sequence
);
1688 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1691 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1692 ssh
->pktout
.data
, ssh
->pktout
.length
+ padding
);
1694 /* Ready-to-send packet starts at ssh->pktout.data. We return length. */
1695 return ssh
->pktout
.length
+ padding
+ maclen
;
1699 * Construct and send an SSH2 packet immediately.
1701 static void ssh2_pkt_send(Ssh ssh
)
1705 len
= ssh2_pkt_construct(ssh
);
1706 backlog
= sk_write(ssh
->s
, (char *)ssh
->pktout
.data
, len
);
1707 if (backlog
> SSH_MAX_BACKLOG
)
1708 ssh_throttle_all(ssh
, 1, backlog
);
1712 * Construct an SSH2 packet and add it to a deferred data block.
1713 * Useful for sending multiple packets in a single sk_write() call,
1714 * to prevent a traffic-analysing listener from being able to work
1715 * out the length of any particular packet (such as the password
1718 * Note that because SSH2 sequence-numbers its packets, this can
1719 * NOT be used as an m4-style `defer' allowing packets to be
1720 * constructed in one order and sent in another.
1722 static void ssh2_pkt_defer(Ssh ssh
)
1724 int len
= ssh2_pkt_construct(ssh
);
1725 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1726 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1727 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1731 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, ssh
->pktout
.data
, len
);
1732 ssh
->deferred_len
+= len
;
1736 * Send the whole deferred data block constructed by
1737 * ssh2_pkt_defer() or SSH1's defer_packet().
1739 static void ssh_pkt_defersend(Ssh ssh
)
1742 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1744 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1745 sfree(ssh
->deferred_send_data
);
1746 ssh
->deferred_send_data
= NULL
;
1747 if (backlog
> SSH_MAX_BACKLOG
)
1748 ssh_throttle_all(ssh
, 1, backlog
);
1752 void bndebug(char *string
, Bignum b
)
1756 p
= ssh2_mpint_fmt(b
, &len
);
1757 debug(("%s", string
));
1758 for (i
= 0; i
< len
; i
++)
1759 debug((" %02x", p
[i
]));
1765 static void sha_mpint(SHA_State
* s
, Bignum b
)
1769 p
= ssh2_mpint_fmt(b
, &len
);
1770 sha_string(s
, p
, len
);
1775 * Packet decode functions for both SSH1 and SSH2.
1777 static unsigned long ssh_pkt_getuint32(Ssh ssh
)
1779 unsigned long value
;
1780 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< 4)
1781 return 0; /* arrgh, no way to decline (FIXME?) */
1782 value
= GET_32BIT(ssh
->pktin
.body
+ ssh
->pktin
.savedpos
);
1783 ssh
->pktin
.savedpos
+= 4;
1786 static int ssh2_pkt_getbool(Ssh ssh
)
1788 unsigned long value
;
1789 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< 1)
1790 return 0; /* arrgh, no way to decline (FIXME?) */
1791 value
= ssh
->pktin
.body
[ssh
->pktin
.savedpos
] != 0;
1792 ssh
->pktin
.savedpos
++;
1795 static void ssh_pkt_getstring(Ssh ssh
, char **p
, int *length
)
1800 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< 4)
1802 len
= GET_32BIT(ssh
->pktin
.body
+ ssh
->pktin
.savedpos
);
1806 ssh
->pktin
.savedpos
+= 4;
1807 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< *length
)
1809 *p
= (char *)(ssh
->pktin
.body
+ ssh
->pktin
.savedpos
);
1810 ssh
->pktin
.savedpos
+= *length
;
1812 static void *ssh_pkt_getdata(Ssh ssh
, int length
)
1814 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< length
)
1816 ssh
->pktin
.savedpos
+= length
;
1817 return ssh
->pktin
.body
+ (ssh
->pktin
.savedpos
- length
);
1819 static int ssh1_pkt_getrsakey(Ssh ssh
, struct RSAKey
*key
,
1820 unsigned char **keystr
)
1824 j
= makekey(ssh
->pktin
.body
+ ssh
->pktin
.savedpos
,
1825 ssh
->pktin
.length
- ssh
->pktin
.savedpos
,
1831 ssh
->pktin
.savedpos
+= j
;
1832 assert(ssh
->pktin
.savedpos
< ssh
->pktin
.length
);
1836 static Bignum
ssh1_pkt_getmp(Ssh ssh
)
1841 j
= ssh1_read_bignum(ssh
->pktin
.body
+ ssh
->pktin
.savedpos
,
1842 ssh
->pktin
.length
- ssh
->pktin
.savedpos
, &b
);
1847 ssh
->pktin
.savedpos
+= j
;
1850 static Bignum
ssh2_pkt_getmp(Ssh ssh
)
1856 ssh_pkt_getstring(ssh
, &p
, &length
);
1860 bombout(("internal error: Can't handle negative mpints"));
1863 b
= bignum_from_bytes((unsigned char *)p
, length
);
1868 * Helper function to add an SSH2 signature blob to a packet.
1869 * Expects to be shown the public key blob as well as the signature
1870 * blob. Normally works just like ssh2_pkt_addstring, but will
1871 * fiddle with the signature packet if necessary for
1872 * BUG_SSH2_RSA_PADDING.
1874 static void ssh2_add_sigblob(Ssh ssh
, void *pkblob_v
, int pkblob_len
,
1875 void *sigblob_v
, int sigblob_len
)
1877 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1878 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1880 /* dmemdump(pkblob, pkblob_len); */
1881 /* dmemdump(sigblob, sigblob_len); */
1884 * See if this is in fact an ssh-rsa signature and a buggy
1885 * server; otherwise we can just do this the easy way.
1887 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1888 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1889 int pos
, len
, siglen
;
1892 * Find the byte length of the modulus.
1895 pos
= 4+7; /* skip over "ssh-rsa" */
1896 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1897 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
1898 pos
+= 4; /* find modulus itself */
1899 while (len
> 0 && pkblob
[pos
] == 0)
1901 /* debug(("modulus length is %d\n", len)); */
1904 * Now find the signature integer.
1906 pos
= 4+7; /* skip over "ssh-rsa" */
1907 siglen
= GET_32BIT(sigblob
+pos
);
1908 /* debug(("signature length is %d\n", siglen)); */
1910 if (len
!= siglen
) {
1911 unsigned char newlen
[4];
1912 ssh2_pkt_addstring_start(ssh
);
1913 ssh2_pkt_addstring_data(ssh
, (char *)sigblob
, pos
);
1914 /* dmemdump(sigblob, pos); */
1915 pos
+= 4; /* point to start of actual sig */
1916 PUT_32BIT(newlen
, len
);
1917 ssh2_pkt_addstring_data(ssh
, (char *)newlen
, 4);
1918 /* dmemdump(newlen, 4); */
1920 while (len
-- > siglen
) {
1921 ssh2_pkt_addstring_data(ssh
, (char *)newlen
, 1);
1922 /* dmemdump(newlen, 1); */
1924 ssh2_pkt_addstring_data(ssh
, (char *)(sigblob
+pos
), siglen
);
1925 /* dmemdump(sigblob+pos, siglen); */
1929 /* Otherwise fall through and do it the easy way. */
1932 ssh2_pkt_addstring_start(ssh
);
1933 ssh2_pkt_addstring_data(ssh
, (char *)sigblob
, sigblob_len
);
1937 * Examine the remote side's version string and compare it against
1938 * a list of known buggy implementations.
1940 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
1942 char *imp
; /* pointer to implementation part */
1944 imp
+= strcspn(imp
, "-");
1946 imp
+= strcspn(imp
, "-");
1949 ssh
->remote_bugs
= 0;
1951 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
1952 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
1953 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
1954 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
1955 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
1956 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
1958 * These versions don't support SSH1_MSG_IGNORE, so we have
1959 * to use a different defence against password length
1962 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
1963 logevent("We believe remote version has SSH1 ignore bug");
1966 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
1967 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
1968 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
1970 * These versions need a plain password sent; they can't
1971 * handle having a null and a random length of data after
1974 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
1975 logevent("We believe remote version needs a plain SSH1 password");
1978 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
1979 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
1980 (!strcmp(imp
, "Cisco-1.25")))) {
1982 * These versions apparently have no clue whatever about
1983 * RSA authentication and will panic and die if they see
1984 * an AUTH_RSA message.
1986 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
1987 logevent("We believe remote version can't handle RSA authentication");
1990 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
1991 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
1992 !wc_match("* VShell", imp
) &&
1993 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
1994 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
1995 wc_match("2.1 *", imp
)))) {
1997 * These versions have the HMAC bug.
1999 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
2000 logevent("We believe remote version has SSH2 HMAC bug");
2003 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2004 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2005 !wc_match("* VShell", imp
) &&
2006 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2008 * These versions have the key-derivation bug (failing to
2009 * include the literal shared secret in the hashes that
2010 * generate the keys).
2012 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2013 logevent("We believe remote version has SSH2 key-derivation bug");
2016 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2017 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2018 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2019 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2021 * These versions have the SSH2 RSA padding bug.
2023 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2024 logevent("We believe remote version has SSH2 RSA padding bug");
2027 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2028 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2029 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2031 * These versions have the SSH2 session-ID bug in
2032 * public-key authentication.
2034 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2035 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2038 if (ssh
->cfg
.sshbug_dhgex2
== FORCE_ON
) {
2040 * User specified the SSH2 DH GEX bug.
2042 ssh
->remote_bugs
|= BUG_SSH2_DH_GEX
;
2043 logevent("We believe remote version has SSH2 DH group exchange bug");
2047 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2049 struct do_ssh_init_state
{
2057 crState(do_ssh_init_state
);
2059 crBegin(ssh
->do_ssh_init_crstate
);
2061 /* Search for the string "SSH-" in the input. */
2064 static const int transS
[] = { 1, 2, 2, 1 };
2065 static const int transH
[] = { 0, 0, 3, 0 };
2066 static const int transminus
[] = { 0, 0, 0, -1 };
2068 s
->i
= transS
[s
->i
];
2070 s
->i
= transH
[s
->i
];
2072 s
->i
= transminus
[s
->i
];
2077 crReturn(1); /* get another character */
2081 s
->vstring
= snewn(s
->vstrsize
, char);
2082 strcpy(s
->vstring
, "SSH-");
2086 crReturn(1); /* get another char */
2087 if (s
->vslen
>= s
->vstrsize
- 1) {
2089 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2091 s
->vstring
[s
->vslen
++] = c
;
2094 s
->version
[s
->i
] = '\0';
2096 } else if (s
->i
< sizeof(s
->version
) - 1)
2097 s
->version
[s
->i
++] = c
;
2098 } else if (c
== '\012')
2102 ssh
->agentfwd_enabled
= FALSE
;
2103 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2105 s
->vstring
[s
->vslen
] = 0;
2106 s
->vstring
[strcspn(s
->vstring
, "\r\n")] = '\0';/* remove EOL chars */
2109 vlog
= snewn(20 + s
->vslen
, char);
2110 sprintf(vlog
, "Server version: %s", s
->vstring
);
2114 ssh_detect_bugs(ssh
, s
->vstring
);
2117 * Decide which SSH protocol version to support.
2120 /* Anything strictly below "2.0" means protocol 1 is supported. */
2121 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2122 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2123 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2125 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2126 bombout(("SSH protocol version 1 required by user but not provided by server"));
2129 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2130 bombout(("SSH protocol version 2 required by user but not provided by server"));
2134 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2138 char verstring
[80], vlog
[100];
2139 sprintf(verstring
, "SSH-2.0-%s", sshver
);
2140 SHA_Init(&ssh
->exhashbase
);
2142 * Hash our version string and their version string.
2144 sha_string(&ssh
->exhashbase
, verstring
, strlen(verstring
));
2145 sha_string(&ssh
->exhashbase
, s
->vstring
, strcspn(s
->vstring
, "\r\n"));
2146 sprintf(vlog
, "We claim version: %s", verstring
);
2148 strcat(verstring
, "\012");
2149 logevent("Using SSH protocol version 2");
2150 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2151 ssh
->protocol
= ssh2_protocol
;
2153 ssh
->s_rdpkt
= ssh2_rdpkt
;
2158 char verstring
[80], vlog
[100];
2159 sprintf(verstring
, "SSH-%s-%s",
2160 (ssh_versioncmp(s
->version
, "1.5") <= 0 ? s
->version
: "1.5"),
2162 sprintf(vlog
, "We claim version: %s", verstring
);
2164 strcat(verstring
, "\012");
2166 logevent("Using SSH protocol version 1");
2167 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2168 ssh
->protocol
= ssh1_protocol
;
2170 ssh
->s_rdpkt
= ssh1_rdpkt
;
2172 update_specials_menu(ssh
->frontend
);
2173 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2180 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2182 crBegin(ssh
->ssh_gotdata_crstate
);
2185 * To begin with, feed the characters one by one to the
2186 * protocol initialisation / selection function do_ssh_init().
2187 * When that returns 0, we're done with the initial greeting
2188 * exchange and can move on to packet discipline.
2191 int ret
; /* need not be kept across crReturn */
2193 crReturnV
; /* more data please */
2194 ret
= do_ssh_init(ssh
, *data
);
2202 * We emerge from that loop when the initial negotiation is
2203 * over and we have selected an s_rdpkt function. Now pass
2204 * everything to s_rdpkt, and then pass the resulting packets
2205 * to the proper protocol handler.
2210 while (datalen
> 0) {
2211 if (ssh
->s_rdpkt(ssh
, &data
, &datalen
) == 0) {
2212 if (ssh
->state
== SSH_STATE_CLOSED
) {
2215 ssh
->protocol(ssh
, NULL
, 0, 1);
2216 if (ssh
->state
== SSH_STATE_CLOSED
) {
2226 static void ssh_do_close(Ssh ssh
)
2229 struct ssh_channel
*c
;
2231 ssh
->state
= SSH_STATE_CLOSED
;
2237 * Now we must shut down any port and X forwardings going
2238 * through this connection.
2240 if (ssh
->channels
) {
2241 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2244 x11_close(c
->u
.x11
.s
);
2247 pfd_close(c
->u
.pfd
.s
);
2250 del234(ssh
->channels
, c
);
2251 if (ssh
->version
== 2)
2252 bufchain_clear(&c
->v
.v2
.outbuffer
);
2258 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2261 Ssh ssh
= (Ssh
) plug
;
2264 /* A socket error has occurred. */
2265 logevent(error_msg
);
2266 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2268 /* Otherwise, the remote side closed the connection normally. */
2273 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2275 Ssh ssh
= (Ssh
) plug
;
2276 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2277 if (ssh
->state
== SSH_STATE_CLOSED
) {
2284 static void ssh_sent(Plug plug
, int bufsize
)
2286 Ssh ssh
= (Ssh
) plug
;
2288 * If the send backlog on the SSH socket itself clears, we
2289 * should unthrottle the whole world if it was throttled.
2291 if (bufsize
< SSH_MAX_BACKLOG
)
2292 ssh_throttle_all(ssh
, 0, bufsize
);
2296 * Connect to specified host and port.
2297 * Returns an error message, or NULL on success.
2298 * Also places the canonical host name into `realhost'. It must be
2299 * freed by the caller.
2301 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2302 char **realhost
, int nodelay
, int keepalive
)
2304 static const struct plug_function_table fn_table
= {
2314 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2315 if (!ssh
->savedhost
)
2316 fatalbox("Out of memory");
2317 strcpy(ssh
->savedhost
, host
);
2320 port
= 22; /* default ssh port */
2321 ssh
->savedport
= port
;
2326 logeventf(ssh
, "Looking up host \"%s\"", host
);
2327 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
);
2328 if ((err
= sk_addr_error(addr
)) != NULL
) {
2338 sk_getaddr(addr
, addrbuf
, 100);
2339 logeventf(ssh
, "Connecting to %s port %d", addrbuf
, port
);
2341 ssh
->fn
= &fn_table
;
2342 ssh
->s
= new_connection(addr
, *realhost
, port
,
2343 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2344 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2353 * Throttle or unthrottle the SSH connection.
2355 static void ssh1_throttle(Ssh ssh
, int adjust
)
2357 int old_count
= ssh
->v1_throttle_count
;
2358 ssh
->v1_throttle_count
+= adjust
;
2359 assert(ssh
->v1_throttle_count
>= 0);
2360 if (ssh
->v1_throttle_count
&& !old_count
) {
2361 sk_set_frozen(ssh
->s
, 1);
2362 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2363 sk_set_frozen(ssh
->s
, 0);
2368 * Throttle or unthrottle _all_ local data streams (for when sends
2369 * on the SSH connection itself back up).
2371 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2374 struct ssh_channel
*c
;
2376 if (enable
== ssh
->throttled_all
)
2378 ssh
->throttled_all
= enable
;
2379 ssh
->overall_bufsize
= bufsize
;
2382 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2384 case CHAN_MAINSESSION
:
2386 * This is treated separately, outside the switch.
2390 x11_override_throttle(c
->u
.x11
.s
, enable
);
2393 /* Agent channels require no buffer management. */
2396 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2403 * Username and password input, abstracted off into routines
2404 * reusable in several places - even between SSH1 and SSH2.
2407 /* Set up a username or password input loop on a given buffer. */
2408 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2410 ssh
->userpass_input_buffer
= buffer
;
2411 ssh
->userpass_input_buflen
= buflen
;
2412 ssh
->userpass_input_bufpos
= 0;
2413 ssh
->userpass_input_echo
= echo
;
2417 * Process some terminal data in the course of username/password
2418 * input. Returns >0 for success (line of input returned in
2419 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2420 * for inconclusive (keep waiting for more input please).
2422 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2427 switch (c
= *in
++) {
2430 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2431 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2436 if (ssh
->userpass_input_bufpos
> 0) {
2437 if (ssh
->userpass_input_echo
)
2438 c_write_str(ssh
, "\b \b");
2439 ssh
->userpass_input_bufpos
--;
2444 while (ssh
->userpass_input_bufpos
> 0) {
2445 if (ssh
->userpass_input_echo
)
2446 c_write_str(ssh
, "\b \b");
2447 ssh
->userpass_input_bufpos
--;
2456 * This simplistic check for printability is disabled
2457 * when we're doing password input, because some people
2458 * have control characters in their passwords.o
2460 if ((!ssh
->userpass_input_echo
||
2461 (c
>= ' ' && c
<= '~') ||
2462 ((unsigned char) c
>= 160))
2463 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2464 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2465 if (ssh
->userpass_input_echo
)
2466 c_write(ssh
, &c
, 1);
2474 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2476 Ssh ssh
= (Ssh
) sshv
;
2478 ssh
->agent_response
= reply
;
2479 ssh
->agent_response_len
= replylen
;
2481 if (ssh
->version
== 1)
2482 do_ssh1_login(ssh
, NULL
, -1, 0);
2484 do_ssh2_authconn(ssh
, NULL
, -1, 0);
2487 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2489 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2491 void *sentreply
= reply
;
2494 /* Fake SSH_AGENT_FAILURE. */
2495 sentreply
= "\0\0\0\1\5";
2498 if (ssh
->version
== 2) {
2499 ssh2_add_channel_data(c
, sentreply
, replylen
);
2502 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2503 PKT_INT
, c
->remoteid
,
2506 PKT_DATA
, sentreply
, replylen
,
2515 * Handle the key exchange and user authentication phases.
2517 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
2520 unsigned char cookie
[8], *ptr
;
2521 struct RSAKey servkey
, hostkey
;
2522 struct MD5Context md5c
;
2523 struct do_ssh1_login_state
{
2525 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2526 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2527 int tried_publickey
, tried_agent
;
2528 int tis_auth_refused
, ccard_auth_refused
;
2529 unsigned char session_id
[16];
2532 void *publickey_blob
;
2533 int publickey_bloblen
;
2539 unsigned char request
[5], *response
, *p
;
2548 crState(do_ssh1_login_state
);
2550 crBegin(ssh
->do_ssh1_login_crstate
);
2555 if (ssh
->pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
2556 bombout(("Public key packet not received"));
2560 logevent("Received public keys");
2562 ptr
= ssh_pkt_getdata(ssh
, 8);
2564 bombout(("SSH1 public key packet stopped before random cookie"));
2567 memcpy(cookie
, ptr
, 8);
2569 if (!ssh1_pkt_getrsakey(ssh
, &servkey
, &s
->keystr1
) ||
2570 !ssh1_pkt_getrsakey(ssh
, &hostkey
, &s
->keystr2
)) {
2571 bombout(("Failed to read SSH1 public keys from public key packet"));
2576 * Log the host key fingerprint.
2580 logevent("Host key fingerprint is:");
2581 strcpy(logmsg
, " ");
2582 hostkey
.comment
= NULL
;
2583 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2584 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2588 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(ssh
);
2589 s
->supported_ciphers_mask
= ssh_pkt_getuint32(ssh
);
2590 s
->supported_auths_mask
= ssh_pkt_getuint32(ssh
);
2592 ssh
->v1_local_protoflags
=
2593 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2594 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2597 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2598 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2599 MD5Update(&md5c
, cookie
, 8);
2600 MD5Final(s
->session_id
, &md5c
);
2602 for (i
= 0; i
< 32; i
++)
2603 ssh
->session_key
[i
] = random_byte();
2606 * Verify that the `bits' and `bytes' parameters match.
2608 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
2609 servkey
.bits
> servkey
.bytes
* 8) {
2610 bombout(("SSH1 public keys were badly formatted"));
2614 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2616 s
->rsabuf
= snewn(s
->len
, unsigned char);
2618 fatalbox("Out of memory");
2621 * Verify the host key.
2625 * First format the key into a string.
2627 int len
= rsastr_len(&hostkey
);
2628 char fingerprint
[100];
2629 char *keystr
= snewn(len
, char);
2631 fatalbox("Out of memory");
2632 rsastr_fmt(keystr
, &hostkey
);
2633 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2634 verify_ssh_host_key(ssh
->frontend
,
2635 ssh
->savedhost
, ssh
->savedport
, "rsa", keystr
,
2640 for (i
= 0; i
< 32; i
++) {
2641 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2643 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2646 if (hostkey
.bytes
> servkey
.bytes
) {
2647 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
2649 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2651 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2653 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2656 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2660 logevent("Encrypted session key");
2663 int cipher_chosen
= 0, warn
= 0;
2664 char *cipher_string
= NULL
;
2666 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2667 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
2668 if (next_cipher
== CIPHER_WARN
) {
2669 /* If/when we choose a cipher, warn about it */
2671 } else if (next_cipher
== CIPHER_AES
) {
2672 /* XXX Probably don't need to mention this. */
2673 logevent("AES not supported in SSH1, skipping");
2675 switch (next_cipher
) {
2676 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2677 cipher_string
= "3DES"; break;
2678 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2679 cipher_string
= "Blowfish"; break;
2680 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2681 cipher_string
= "single-DES"; break;
2683 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2687 if (!cipher_chosen
) {
2688 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2689 bombout(("Server violates SSH 1 protocol by not "
2690 "supporting 3DES encryption"));
2692 /* shouldn't happen */
2693 bombout(("No supported ciphers found"));
2697 /* Warn about chosen cipher if necessary. */
2699 askcipher(ssh
->frontend
, cipher_string
, 0);
2702 switch (s
->cipher_type
) {
2703 case SSH_CIPHER_3DES
:
2704 logevent("Using 3DES encryption");
2706 case SSH_CIPHER_DES
:
2707 logevent("Using single-DES encryption");
2709 case SSH_CIPHER_BLOWFISH
:
2710 logevent("Using Blowfish encryption");
2714 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
2715 PKT_CHAR
, s
->cipher_type
,
2716 PKT_DATA
, cookie
, 8,
2717 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
2718 PKT_DATA
, s
->rsabuf
, s
->len
,
2719 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
2721 logevent("Trying to enable encryption...");
2725 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2726 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
2728 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
2729 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
2730 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
2732 ssh
->crcda_ctx
= crcda_make_context();
2733 logevent("Installing CRC compensation attack detector");
2735 if (servkey
.modulus
) {
2736 sfree(servkey
.modulus
);
2737 servkey
.modulus
= NULL
;
2739 if (servkey
.exponent
) {
2740 sfree(servkey
.exponent
);
2741 servkey
.exponent
= NULL
;
2743 if (hostkey
.modulus
) {
2744 sfree(hostkey
.modulus
);
2745 hostkey
.modulus
= NULL
;
2747 if (hostkey
.exponent
) {
2748 sfree(hostkey
.exponent
);
2749 hostkey
.exponent
= NULL
;
2753 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2754 bombout(("Encryption not successfully enabled"));
2758 logevent("Successfully started encryption");
2762 if ((flags
& FLAG_INTERACTIVE
) && !*ssh
->cfg
.username
) {
2763 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2764 if (!ssh_get_line("login as: ",
2765 s
->username
, sizeof(s
->username
), FALSE
)) {
2767 * get_line failed to get a username.
2770 logevent("No username provided. Abandoning session.");
2771 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2775 int ret
; /* need not be kept over crReturn */
2776 c_write_str(ssh
, "login as: ");
2779 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
2781 crWaitUntil(!ispkt
);
2782 ret
= process_userpass_input(ssh
, in
, inlen
);
2786 c_write_str(ssh
, "\r\n");
2789 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
2790 s
->username
[sizeof(s
->username
)-1] = '\0';
2793 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
2795 char userlog
[22 + sizeof(s
->username
)];
2796 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
2798 if (flags
& FLAG_INTERACTIVE
&&
2799 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2800 strcat(userlog
, "\r\n");
2801 c_write_str(ssh
, userlog
);
2808 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2809 /* We must not attempt PK auth. Pretend we've already tried it. */
2810 s
->tried_publickey
= s
->tried_agent
= 1;
2812 s
->tried_publickey
= s
->tried_agent
= 0;
2814 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
2815 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
2816 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
2817 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
2818 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
2819 s
->publickey_blob
= NULL
;
2821 s
->publickey_blob
= NULL
;
2823 while (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
2824 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2826 if (agent_exists() && !s
->tried_agent
) {
2828 * Attempt RSA authentication using Pageant.
2834 logevent("Pageant is running. Requesting keys.");
2836 /* Request the keys held by the agent. */
2837 PUT_32BIT(s
->request
, 1);
2838 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2839 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
2840 ssh_agent_callback
, ssh
)) {
2844 bombout(("Unexpected data from server while waiting"
2845 " for agent response"));
2848 } while (ispkt
|| inlen
> 0);
2849 r
= ssh
->agent_response
;
2850 s
->responselen
= ssh
->agent_response_len
;
2852 s
->response
= (unsigned char *) r
;
2853 if (s
->response
&& s
->responselen
>= 5 &&
2854 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
2855 s
->p
= s
->response
+ 5;
2856 s
->nkeys
= GET_32BIT(s
->p
);
2860 sprintf(buf
, "Pageant has %d SSH1 keys", s
->nkeys
);
2863 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
2866 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
2869 if (s
->publickey_blob
&&
2870 !memcmp(s
->p
, s
->publickey_blob
,
2871 s
->publickey_bloblen
)) {
2872 logevent("This key matches configured key file");
2873 s
->tried_publickey
= 1;
2878 do { /* do while (0) to make breaking easy */
2879 n
= ssh1_read_bignum
2880 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
2885 n
= ssh1_read_bignum
2886 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
2891 if (s
->responselen
- (s
->p
-s
->response
) < 4)
2893 s
->commentlen
= GET_32BIT(s
->p
);
2895 if (s
->responselen
- (s
->p
-s
->response
) <
2898 s
->commentp
= (char *)s
->p
;
2899 s
->p
+= s
->commentlen
;
2903 logevent("Pageant key list packet was truncated");
2907 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
2908 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
2910 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2911 logevent("Key refused");
2914 logevent("Received RSA challenge");
2915 if ((s
->challenge
= ssh1_pkt_getmp(ssh
)) == NULL
) {
2916 bombout(("Server's RSA challenge was badly formatted"));
2921 char *agentreq
, *q
, *ret
;
2924 len
= 1 + 4; /* message type, bit count */
2925 len
+= ssh1_bignum_length(s
->key
.exponent
);
2926 len
+= ssh1_bignum_length(s
->key
.modulus
);
2927 len
+= ssh1_bignum_length(s
->challenge
);
2928 len
+= 16; /* session id */
2929 len
+= 4; /* response format */
2930 agentreq
= snewn(4 + len
, char);
2931 PUT_32BIT(agentreq
, len
);
2933 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
2934 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
2936 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
2937 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
2938 q
+= ssh1_write_bignum(q
, s
->challenge
);
2939 memcpy(q
, s
->session_id
, 16);
2941 PUT_32BIT(q
, 1); /* response format */
2942 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
2943 ssh_agent_callback
, ssh
)) {
2948 bombout(("Unexpected data from server"
2949 " while waiting for agent"
2953 } while (ispkt
|| inlen
> 0);
2954 vret
= ssh
->agent_response
;
2955 retlen
= ssh
->agent_response_len
;
2960 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
2961 logevent("Sending Pageant's response");
2962 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
2963 PKT_DATA
, ret
+ 5, 16,
2967 if (ssh
->pktin
.type
== SSH1_SMSG_SUCCESS
) {
2969 ("Pageant's response accepted");
2970 if (flags
& FLAG_VERBOSE
) {
2971 c_write_str(ssh
, "Authenticated using"
2973 c_write(ssh
, s
->commentp
,
2975 c_write_str(ssh
, "\" from agent\r\n");
2980 ("Pageant's response not accepted");
2983 ("Pageant failed to answer challenge");
2987 logevent("No reply received from Pageant");
2990 freebn(s
->key
.exponent
);
2991 freebn(s
->key
.modulus
);
2992 freebn(s
->challenge
);
3001 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
3002 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
3004 if (ssh
->cfg
.try_tis_auth
&&
3005 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3006 !s
->tis_auth_refused
) {
3007 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3008 logevent("Requested TIS authentication");
3009 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3011 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3012 logevent("TIS authentication declined");
3013 if (flags
& FLAG_INTERACTIVE
)
3014 c_write_str(ssh
, "TIS authentication refused.\r\n");
3015 s
->tis_auth_refused
= 1;
3021 ssh_pkt_getstring(ssh
, &challenge
, &challengelen
);
3023 bombout(("TIS challenge packet was badly formed"));
3026 logevent("Received TIS challenge");
3027 if (challengelen
> sizeof(s
->prompt
) - 1)
3028 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3029 memcpy(s
->prompt
, challenge
, challengelen
);
3030 /* Prompt heuristic comes from OpenSSH */
3031 strncpy(s
->prompt
+ challengelen
,
3032 memchr(s
->prompt
, '\n', challengelen
) ?
3033 "": "\r\nResponse: ",
3034 (sizeof s
->prompt
) - challengelen
);
3035 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
3038 if (ssh
->cfg
.try_tis_auth
&&
3039 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3040 !s
->ccard_auth_refused
) {
3041 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3042 logevent("Requested CryptoCard authentication");
3043 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3045 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3046 logevent("CryptoCard authentication declined");
3047 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3048 s
->ccard_auth_refused
= 1;
3054 ssh_pkt_getstring(ssh
, &challenge
, &challengelen
);
3056 bombout(("CryptoCard challenge packet was badly formed"));
3059 logevent("Received CryptoCard challenge");
3060 if (challengelen
> sizeof(s
->prompt
) - 1)
3061 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3062 memcpy(s
->prompt
, challenge
, challengelen
);
3063 strncpy(s
->prompt
+ challengelen
,
3064 memchr(s
->prompt
, '\n', challengelen
) ?
3065 "" : "\r\nResponse: ",
3066 sizeof(s
->prompt
) - challengelen
);
3067 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
3070 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3071 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
3072 s
->username
, ssh
->savedhost
);
3074 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3075 char *comment
= NULL
;
3078 if (flags
& FLAG_VERBOSE
)
3079 c_write_str(ssh
, "Trying public key authentication.\r\n");
3080 logeventf(ssh
, "Trying public key \"%s\"",
3081 filename_to_str(&ssh
->cfg
.keyfile
));
3082 type
= key_type(&ssh
->cfg
.keyfile
);
3083 if (type
!= SSH_KEYTYPE_SSH1
) {
3084 sprintf(msgbuf
, "Key is of wrong type (%s)",
3085 key_type_to_str(type
));
3087 c_write_str(ssh
, msgbuf
);
3088 c_write_str(ssh
, "\r\n");
3089 s
->tried_publickey
= 1;
3092 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
3093 if (flags
& FLAG_VERBOSE
)
3094 c_write_str(ssh
, "No passphrase required.\r\n");
3097 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
3102 * Show password prompt, having first obtained it via a TIS
3103 * or CryptoCard exchange if we're doing TIS or CryptoCard
3107 if (!ssh_get_line(s
->prompt
, s
->password
,
3108 sizeof(s
->password
), TRUE
)) {
3110 * get_line failed to get a password (for example
3111 * because one was supplied on the command line
3112 * which has already failed to work). Terminate.
3114 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
3115 PKT_STR
, "No more passwords available to try",
3117 logevent("Unable to authenticate");
3118 connection_fatal(ssh
->frontend
, "Unable to authenticate");
3119 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3123 /* Prompt may have come from server. We've munged it a bit, so
3124 * we know it to be zero-terminated at least once. */
3125 int ret
; /* need not be saved over crReturn */
3126 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3129 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3131 crWaitUntil(!ispkt
);
3132 ret
= process_userpass_input(ssh
, in
, inlen
);
3136 c_write_str(ssh
, "\r\n");
3140 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3142 * Try public key authentication with the specified
3145 s
->tried_publickey
= 1;
3148 const char *error
= NULL
;
3149 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3152 c_write_str(ssh
, "Couldn't load private key from ");
3153 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3154 c_write_str(ssh
, " (");
3155 c_write_str(ssh
, error
);
3156 c_write_str(ssh
, ").\r\n");
3157 continue; /* go and try password */
3160 c_write_str(ssh
, "Wrong passphrase.\r\n");
3161 s
->tried_publickey
= 0;
3162 continue; /* try again */
3167 * Send a public key attempt.
3169 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3170 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3173 if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3174 c_write_str(ssh
, "Server refused our public key.\r\n");
3175 continue; /* go and try password */
3177 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3178 bombout(("Bizarre response to offer of public key"));
3184 unsigned char buffer
[32];
3185 Bignum challenge
, response
;
3187 if ((challenge
= ssh1_pkt_getmp(ssh
)) == NULL
) {
3188 bombout(("Server's RSA challenge was badly formatted"));
3191 response
= rsadecrypt(challenge
, &s
->key
);
3192 freebn(s
->key
.private_exponent
);/* burn the evidence */
3194 for (i
= 0; i
< 32; i
++) {
3195 buffer
[i
] = bignum_byte(response
, 31 - i
);
3199 MD5Update(&md5c
, buffer
, 32);
3200 MD5Update(&md5c
, s
->session_id
, 16);
3201 MD5Final(buffer
, &md5c
);
3203 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3204 PKT_DATA
, buffer
, 16, PKT_END
);
3211 if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3212 if (flags
& FLAG_VERBOSE
)
3213 c_write_str(ssh
, "Failed to authenticate with"
3214 " our public key.\r\n");
3215 continue; /* go and try password */
3216 } else if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
) {
3217 bombout(("Bizarre response to RSA authentication response"));
3221 break; /* we're through! */
3223 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3225 * Defence against traffic analysis: we send a
3226 * whole bunch of packets containing strings of
3227 * different lengths. One of these strings is the
3228 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3229 * The others are all random data in
3230 * SSH1_MSG_IGNORE packets. This way a passive
3231 * listener can't tell which is the password, and
3232 * hence can't deduce the password length.
3234 * Anybody with a password length greater than 16
3235 * bytes is going to have enough entropy in their
3236 * password that a listener won't find it _that_
3237 * much help to know how long it is. So what we'll
3240 * - if password length < 16, we send 15 packets
3241 * containing string lengths 1 through 15
3243 * - otherwise, we let N be the nearest multiple
3244 * of 8 below the password length, and send 8
3245 * packets containing string lengths N through
3246 * N+7. This won't obscure the order of
3247 * magnitude of the password length, but it will
3248 * introduce a bit of extra uncertainty.
3250 * A few servers (the old 1.2.18 through 1.2.22)
3251 * can't deal with SSH1_MSG_IGNORE. For these
3252 * servers, we need an alternative defence. We make
3253 * use of the fact that the password is interpreted
3254 * as a C string: so we can append a NUL, then some
3257 * One server (a Cisco one) can deal with neither
3258 * SSH1_MSG_IGNORE _nor_ a padded password string.
3259 * For this server we are left with no defences
3260 * against password length sniffing.
3262 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3264 * The server can deal with SSH1_MSG_IGNORE, so
3265 * we can use the primary defence.
3267 int bottom
, top
, pwlen
, i
;
3270 pwlen
= strlen(s
->password
);
3272 bottom
= 0; /* zero length passwords are OK! :-) */
3275 bottom
= pwlen
& ~7;
3279 assert(pwlen
>= bottom
&& pwlen
<= top
);
3281 randomstr
= snewn(top
+ 1, char);
3283 for (i
= bottom
; i
<= top
; i
++) {
3285 defer_packet(ssh
, s
->pwpkt_type
,
3286 PKTT_PASSWORD
, PKT_STR
, s
->password
,
3287 PKTT_OTHER
, PKT_END
);
3289 for (j
= 0; j
< i
; j
++) {
3291 randomstr
[j
] = random_byte();
3292 } while (randomstr
[j
] == '\0');
3294 randomstr
[i
] = '\0';
3295 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3296 PKT_STR
, randomstr
, PKT_END
);
3299 logevent("Sending password with camouflage packets");
3300 ssh_pkt_defersend(ssh
);
3303 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3305 * The server can't deal with SSH1_MSG_IGNORE
3306 * but can deal with padded passwords, so we
3307 * can use the secondary defence.
3313 len
= strlen(s
->password
);
3314 if (len
< sizeof(string
)) {
3316 strcpy(string
, s
->password
);
3317 len
++; /* cover the zero byte */
3318 while (len
< sizeof(string
)) {
3319 string
[len
++] = (char) random_byte();
3324 logevent("Sending length-padded password");
3325 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3326 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3327 PKTT_OTHER
, PKT_END
);
3330 * The server has _both_
3331 * BUG_CHOKES_ON_SSH1_IGNORE and
3332 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3333 * therefore nothing we can do.
3336 len
= strlen(s
->password
);
3337 logevent("Sending unpadded password");
3338 send_packet(ssh
, s
->pwpkt_type
,
3339 PKTT_PASSWORD
, PKT_INT
, len
,
3340 PKT_DATA
, s
->password
, len
,
3341 PKTT_OTHER
, PKT_END
);
3344 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3345 PKT_STR
, s
->password
, PKTT_OTHER
, PKT_END
);
3348 logevent("Sent password");
3349 memset(s
->password
, 0, strlen(s
->password
));
3351 if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3352 if (flags
& FLAG_VERBOSE
)
3353 c_write_str(ssh
, "Access denied\r\n");
3354 logevent("Authentication refused");
3355 } else if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
) {
3356 bombout(("Strange packet received, type %d", ssh
->pktin
.type
));
3361 logevent("Authentication successful");
3366 void sshfwd_close(struct ssh_channel
*c
)
3370 if (ssh
->state
!= SSH_STATE_SESSION
) {
3371 assert(ssh
->state
== SSH_STATE_CLOSED
);
3375 if (c
&& !c
->closes
) {
3377 * If the channel's remoteid is -1, we have sent
3378 * CHANNEL_OPEN for this channel, but it hasn't even been
3379 * acknowledged by the server. So we must set a close flag
3380 * on it now, and then when the server acks the channel
3381 * open, we can close it then.
3383 if (((int)c
->remoteid
) != -1) {
3384 if (ssh
->version
== 1) {
3385 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3388 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_CLOSE
);
3389 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
3393 c
->closes
= 1; /* sent MSG_CLOSE */
3394 if (c
->type
== CHAN_X11
) {
3396 logevent("Forwarded X11 connection terminated");
3397 } else if (c
->type
== CHAN_SOCKDATA
||
3398 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3400 logevent("Forwarded port closed");
3405 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3409 if (ssh
->state
!= SSH_STATE_SESSION
) {
3410 assert(ssh
->state
== SSH_STATE_CLOSED
);
3414 if (ssh
->version
== 1) {
3415 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3416 PKT_INT
, c
->remoteid
,
3418 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3419 PKTT_OTHER
, PKT_END
);
3421 * In SSH1 we can return 0 here - implying that forwarded
3422 * connections are never individually throttled - because
3423 * the only circumstance that can cause throttling will be
3424 * the whole SSH connection backing up, in which case
3425 * _everything_ will be throttled as a whole.
3429 ssh2_add_channel_data(c
, buf
, len
);
3430 return ssh2_try_send(c
);
3434 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3438 if (ssh
->state
!= SSH_STATE_SESSION
) {
3439 assert(ssh
->state
== SSH_STATE_CLOSED
);
3443 if (ssh
->version
== 1) {
3444 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3445 c
->v
.v1
.throttling
= 0;
3446 ssh1_throttle(ssh
, -1);
3449 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3453 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
3455 crBegin(ssh
->ssh1_protocol_crstate
);
3459 while (!do_ssh1_login(ssh
, in
, inlen
, ispkt
)) {
3462 if (ssh
->state
== SSH_STATE_CLOSED
)
3465 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
3466 logevent("Requesting agent forwarding");
3467 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
3471 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3472 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3473 bombout(("Protocol confusion"));
3475 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3476 logevent("Agent forwarding refused");
3478 logevent("Agent forwarding enabled");
3479 ssh
->agentfwd_enabled
= TRUE
;
3483 if (ssh
->cfg
.x11_forward
) {
3484 char proto
[20], data
[64];
3485 logevent("Requesting X11 forwarding");
3486 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
3487 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
3488 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
3489 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
3490 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
3491 PKT_STR
, proto
, PKT_STR
, data
,
3492 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
3495 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
3496 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
3501 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3502 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3503 bombout(("Protocol confusion"));
3505 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3506 logevent("X11 forwarding refused");
3508 logevent("X11 forwarding enabled");
3509 ssh
->X11_fwd_enabled
= TRUE
;
3516 int sport
,dport
,sserv
,dserv
;
3517 char sports
[256], dports
[256], saddr
[256], host
[256];
3519 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3520 /* Add port forwardings. */
3521 ssh
->portfwd_strptr
= ssh
->cfg
.portfwd
;
3522 while (*ssh
->portfwd_strptr
) {
3523 type
= *ssh
->portfwd_strptr
++;
3526 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= '\t') {
3527 if (*ssh
->portfwd_strptr
== ':') {
3529 * We've seen a colon in the middle of the
3530 * source port number. This means that
3531 * everything we've seen until now is the
3532 * source _address_, so we'll move it into
3533 * saddr and start sports from the beginning
3536 ssh
->portfwd_strptr
++;
3538 strcpy(saddr
, sports
);
3541 if (n
< 255) sports
[n
++] = *ssh
->portfwd_strptr
++;
3545 if (*ssh
->portfwd_strptr
== '\t')
3546 ssh
->portfwd_strptr
++;
3548 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= ':') {
3549 if (n
< 255) host
[n
++] = *ssh
->portfwd_strptr
++;
3552 if (*ssh
->portfwd_strptr
== ':')
3553 ssh
->portfwd_strptr
++;
3555 while (*ssh
->portfwd_strptr
) {
3556 if (n
< 255) dports
[n
++] = *ssh
->portfwd_strptr
++;
3559 ssh
->portfwd_strptr
++;
3560 dport
= atoi(dports
);
3564 dport
= net_service_lookup(dports
);
3566 logeventf(ssh
, "Service lookup failed for"
3567 " destination port \"%s\"", dports
);
3571 while (*ssh
->portfwd_strptr
) ssh
->portfwd_strptr
++;
3573 ssh
->portfwd_strptr
++; /* eat the NUL and move to next one */
3575 sport
= atoi(sports
);
3579 sport
= net_service_lookup(sports
);
3581 logeventf(ssh
, "Service lookup failed for source"
3582 " port \"%s\"", sports
);
3585 if (sport
&& dport
) {
3586 /* Set up a description of the source port. */
3587 char *sportdesc
= dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
3588 (int)(*saddr?
strlen(saddr
):0), *saddr?saddr
:NULL
,
3589 (int)(*saddr?
1:0), ":",
3590 (int)(sserv ?
strlen(sports
) : 0), sports
,
3591 sserv
, "(", sport
, sserv
, ")");
3593 /* Verbose description of the destination port */
3594 char *dportdesc
= dupprintf("%s:%.*s%.*s%d%.*s",
3596 (int)(dserv ?
strlen(dports
) : 0), dports
,
3597 dserv
, "(", dport
, dserv
, ")");
3598 const char *err
= pfd_addforward(host
, dport
,
3599 *saddr ? saddr
: NULL
,
3600 sport
, ssh
, &ssh
->cfg
);
3602 logeventf(ssh
, "Local port %s forward to %s"
3603 " failed: %s", sportdesc
, dportdesc
, err
);
3605 logeventf(ssh
, "Local port %s forwarding to %s",
3606 sportdesc
, dportdesc
);
3609 } else if (type
== 'D') {
3610 const char *err
= pfd_addforward(NULL
, -1,
3611 *saddr ? saddr
: NULL
,
3612 sport
, ssh
, &ssh
->cfg
);
3614 logeventf(ssh
, "Local port %s SOCKS dynamic forward"
3615 " setup failed: %s", sportdesc
, err
);
3617 logeventf(ssh
, "Local port %s doing SOCKS"
3618 " dynamic forwarding", sportdesc
);
3621 struct ssh_rportfwd
*pf
;
3622 pf
= snew(struct ssh_rportfwd
);
3623 strcpy(pf
->dhost
, host
);
3627 "SSH1 cannot handle source address spec \"%s:%d\"; ignoring",
3630 if (add234(ssh
->rportfwds
, pf
) != pf
) {
3632 "Duplicate remote port forwarding to %s:%d",
3636 logeventf(ssh
, "Requesting remote port %.*s%.*s%d%.*s"
3637 " forward to %s:%.*s%.*s%d%.*s",
3638 (int)(sserv ?
strlen(sports
) : 0), sports
,
3639 sserv
, "(", sport
, sserv
, ")",
3641 (int)(dserv ?
strlen(dports
) : 0), dports
,
3642 dserv
, "(", dport
, dserv
, ")");
3643 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
3651 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3652 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3653 bombout(("Protocol confusion"));
3655 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3656 c_write_str(ssh
, "Server refused port"
3659 logevent("Remote port forwarding enabled");
3667 if (!ssh
->cfg
.nopty
) {
3668 /* Unpick the terminal-speed string. */
3669 /* XXX perhaps we should allow no speeds to be sent. */
3670 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
3671 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
3672 /* Send the pty request. */
3673 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
3674 PKT_STR
, ssh
->cfg
.termtype
,
3675 PKT_INT
, ssh
->term_height
,
3676 PKT_INT
, ssh
->term_width
,
3677 PKT_INT
, 0, PKT_INT
, 0, /* width,height in pixels */
3678 PKT_CHAR
, 192, PKT_INT
, ssh
->ispeed
, /* TTY_OP_ISPEED */
3679 PKT_CHAR
, 193, PKT_INT
, ssh
->ospeed
, /* TTY_OP_OSPEED */
3680 PKT_CHAR
, 0, PKT_END
);
3681 ssh
->state
= SSH_STATE_INTERMED
;
3685 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3686 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3687 bombout(("Protocol confusion"));
3689 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3690 c_write_str(ssh
, "Server refused to allocate pty\r\n");
3691 ssh
->editing
= ssh
->echoing
= 1;
3693 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
3694 ssh
->ospeed
, ssh
->ispeed
);
3696 ssh
->editing
= ssh
->echoing
= 1;
3699 if (ssh
->cfg
.compression
) {
3700 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
3704 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3705 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3706 bombout(("Protocol confusion"));
3708 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3709 c_write_str(ssh
, "Server refused to compress\r\n");
3711 logevent("Started compression");
3712 ssh
->v1_compressing
= TRUE
;
3713 ssh
->cs_comp_ctx
= zlib_compress_init();
3714 logevent("Initialised zlib (RFC1950) compression");
3715 ssh
->sc_comp_ctx
= zlib_decompress_init();
3716 logevent("Initialised zlib (RFC1950) decompression");
3720 * Start the shell or command.
3722 * Special case: if the first-choice command is an SSH2
3723 * subsystem (hence not usable here) and the second choice
3724 * exists, we fall straight back to that.
3727 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
3729 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
3730 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
3731 ssh
->fallback_cmd
= TRUE
;
3734 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
3736 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
3737 logevent("Started session");
3740 ssh
->state
= SSH_STATE_SESSION
;
3741 if (ssh
->size_needed
)
3742 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
3743 if (ssh
->eof_needed
)
3744 ssh_special(ssh
, TS_EOF
);
3747 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
3749 ssh
->channels
= newtree234(ssh_channelcmp
);
3753 if (ssh
->pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
3754 ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
3756 int stringlen
, bufsize
;
3758 ssh_pkt_getstring(ssh
, &string
, &stringlen
);
3759 if (string
== NULL
) {
3760 bombout(("Incoming terminal data packet was badly formed"));
3765 from_backend(ssh
->frontend
,
3766 ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
,
3768 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3769 ssh
->v1_stdout_throttling
= 1;
3770 ssh1_throttle(ssh
, +1);
3772 } else if (ssh
->pktin
.type
== SSH1_MSG_DISCONNECT
) {
3773 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3774 logevent("Received disconnect request");
3776 } else if (ssh
->pktin
.type
== SSH1_SMSG_X11_OPEN
) {
3777 /* Remote side is trying to open a channel to talk to our
3778 * X-Server. Give them back a local channel number. */
3779 struct ssh_channel
*c
;
3780 int remoteid
= ssh_pkt_getuint32(ssh
);
3782 logevent("Received X11 connect request");
3783 /* Refuse if X11 forwarding is disabled. */
3784 if (!ssh
->X11_fwd_enabled
) {
3785 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3786 PKT_INT
, remoteid
, PKT_END
);
3787 logevent("Rejected X11 connect request");
3789 c
= snew(struct ssh_channel
);
3792 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
3793 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
3794 logevent("Opening X11 forward connection failed");
3796 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3797 PKT_INT
, remoteid
, PKT_END
);
3800 ("Opening X11 forward connection succeeded");
3801 c
->remoteid
= remoteid
;
3802 c
->localid
= alloc_channel_id(ssh
);
3804 c
->v
.v1
.throttling
= 0;
3805 c
->type
= CHAN_X11
; /* identify channel type */
3806 add234(ssh
->channels
, c
);
3807 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3808 PKT_INT
, c
->remoteid
, PKT_INT
,
3809 c
->localid
, PKT_END
);
3810 logevent("Opened X11 forward channel");
3813 } else if (ssh
->pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
3814 /* Remote side is trying to open a channel to talk to our
3815 * agent. Give them back a local channel number. */
3816 struct ssh_channel
*c
;
3817 int remoteid
= ssh_pkt_getuint32(ssh
);
3819 /* Refuse if agent forwarding is disabled. */
3820 if (!ssh
->agentfwd_enabled
) {
3821 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3822 PKT_INT
, remoteid
, PKT_END
);
3824 c
= snew(struct ssh_channel
);
3826 c
->remoteid
= remoteid
;
3827 c
->localid
= alloc_channel_id(ssh
);
3829 c
->v
.v1
.throttling
= 0;
3830 c
->type
= CHAN_AGENT
; /* identify channel type */
3831 c
->u
.a
.lensofar
= 0;
3832 add234(ssh
->channels
, c
);
3833 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3834 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
3837 } else if (ssh
->pktin
.type
== SSH1_MSG_PORT_OPEN
) {
3838 /* Remote side is trying to open a channel to talk to a
3839 * forwarded port. Give them back a local channel number. */
3840 struct ssh_channel
*c
;
3841 struct ssh_rportfwd pf
;
3844 char *host
, buf
[1024];
3846 c
= snew(struct ssh_channel
);
3849 remoteid
= ssh_pkt_getuint32(ssh
);
3850 ssh_pkt_getstring(ssh
, &host
, &hostsize
);
3851 port
= ssh_pkt_getuint32(ssh
);
3853 if (hostsize
>= lenof(pf
.dhost
))
3854 hostsize
= lenof(pf
.dhost
)-1;
3855 memcpy(pf
.dhost
, host
, hostsize
);
3856 pf
.dhost
[hostsize
] = '\0';
3859 if (find234(ssh
->rportfwds
, &pf
, NULL
) == NULL
) {
3860 sprintf(buf
, "Rejected remote port open request for %s:%d",
3863 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3864 PKT_INT
, remoteid
, PKT_END
);
3866 sprintf(buf
, "Received remote port open request for %s:%d",
3869 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
3873 sprintf(buf
, "Port open failed: %s", e
);
3876 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3877 PKT_INT
, remoteid
, PKT_END
);
3879 c
->remoteid
= remoteid
;
3880 c
->localid
= alloc_channel_id(ssh
);
3882 c
->v
.v1
.throttling
= 0;
3883 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
3884 add234(ssh
->channels
, c
);
3885 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3886 PKT_INT
, c
->remoteid
, PKT_INT
,
3887 c
->localid
, PKT_END
);
3888 logevent("Forwarded port opened successfully");
3892 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
) {
3893 unsigned int remoteid
= ssh_pkt_getuint32(ssh
);
3894 unsigned int localid
= ssh_pkt_getuint32(ssh
);
3895 struct ssh_channel
*c
;
3897 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
3898 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3899 c
->remoteid
= localid
;
3900 c
->type
= CHAN_SOCKDATA
;
3901 c
->v
.v1
.throttling
= 0;
3902 pfd_confirm(c
->u
.pfd
.s
);
3905 if (c
&& c
->closes
) {
3907 * We have a pending close on this channel,
3908 * which we decided on before the server acked
3909 * the channel open. So now we know the
3910 * remoteid, we can close it again.
3912 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
3913 PKT_INT
, c
->remoteid
, PKT_END
);
3916 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_OPEN_FAILURE
) {
3917 unsigned int remoteid
= ssh_pkt_getuint32(ssh
);
3918 struct ssh_channel
*c
;
3920 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
3921 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3922 logevent("Forwarded connection refused by server");
3923 pfd_close(c
->u
.pfd
.s
);
3924 del234(ssh
->channels
, c
);
3928 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
3929 ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
3930 /* Remote side closes a channel. */
3931 unsigned i
= ssh_pkt_getuint32(ssh
);
3932 struct ssh_channel
*c
;
3933 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
3934 if (c
&& ((int)c
->remoteid
) != -1) {
3937 (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
3939 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
3940 logevent("Forwarded X11 connection terminated");
3941 assert(c
->u
.x11
.s
!= NULL
);
3942 x11_close(c
->u
.x11
.s
);
3945 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
3946 logevent("Forwarded port closed");
3947 assert(c
->u
.pfd
.s
!= NULL
);
3948 pfd_close(c
->u
.pfd
.s
);
3952 c
->closes
|= (closetype
<< 2); /* seen this message */
3953 if (!(c
->closes
& closetype
)) {
3954 send_packet(ssh
, ssh
->pktin
.type
, PKT_INT
, c
->remoteid
,
3956 c
->closes
|= closetype
; /* sent it too */
3959 if (c
->closes
== 15) {
3960 del234(ssh
->channels
, c
);
3964 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
3965 ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
3966 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
3970 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
3971 /* Data sent down one of our channels. */
3972 int i
= ssh_pkt_getuint32(ssh
);
3975 struct ssh_channel
*c
;
3977 ssh_pkt_getstring(ssh
, &p
, &len
);
3979 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
3984 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
3987 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
3990 /* Data for an agent message. Buffer it. */
3992 if (c
->u
.a
.lensofar
< 4) {
3993 int l
= min(4 - c
->u
.a
.lensofar
, len
);
3994 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
3998 c
->u
.a
.lensofar
+= l
;
4000 if (c
->u
.a
.lensofar
== 4) {
4002 4 + GET_32BIT(c
->u
.a
.msglen
);
4003 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
4005 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
4007 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
4009 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
4011 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
4015 c
->u
.a
.lensofar
+= l
;
4017 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
4020 if (agent_query(c
->u
.a
.message
,
4023 ssh_agentf_callback
, c
))
4024 ssh_agentf_callback(c
, reply
, replylen
);
4025 sfree(c
->u
.a
.message
);
4026 c
->u
.a
.lensofar
= 0;
4029 bufsize
= 0; /* agent channels never back up */
4032 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4033 c
->v
.v1
.throttling
= 1;
4034 ssh1_throttle(ssh
, +1);
4037 } else if (ssh
->pktin
.type
== SSH1_SMSG_SUCCESS
) {
4038 /* may be from EXEC_SHELL on some servers */
4039 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
4040 /* may be from EXEC_SHELL on some servers
4041 * if no pty is available or in other odd cases. Ignore */
4042 } else if (ssh
->pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
4044 ssh
->exitcode
= ssh_pkt_getuint32(ssh
);
4045 sprintf(buf
, "Server sent command exit status %d",
4048 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
4050 * In case `helpful' firewalls or proxies tack
4051 * extra human-readable text on the end of the
4052 * session which we might mistake for another
4053 * encrypted packet, we close the session once
4054 * we've sent EXIT_CONFIRMATION.
4056 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4059 bombout(("Strange packet received: type %d", ssh
->pktin
.type
));
4064 int len
= min(inlen
, 512);
4065 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4066 PKT_INT
, len
, PKT_DATA
, in
, len
,
4067 PKTT_OTHER
, PKT_END
);
4078 * Utility routine for decoding comma-separated strings in KEXINIT.
4080 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
4083 if (!needle
|| !haystack
) /* protect against null pointers */
4085 needlen
= strlen(needle
);
4088 * Is it at the start of the string?
4090 if (haylen
>= needlen
&& /* haystack is long enough */
4091 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4092 (haylen
== needlen
|| haystack
[needlen
] == ',')
4093 /* either , or EOS follows */
4097 * If not, search for the next comma and resume after that.
4098 * If no comma found, terminate.
4100 while (haylen
> 0 && *haystack
!= ',')
4101 haylen
--, haystack
++;
4104 haylen
--, haystack
++; /* skip over comma itself */
4109 * SSH2 key creation method.
4111 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
4112 unsigned char *sessid
, char chr
,
4113 unsigned char *keyspace
)
4116 /* First 20 bytes. */
4118 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4120 SHA_Bytes(&s
, H
, 20);
4121 SHA_Bytes(&s
, &chr
, 1);
4122 SHA_Bytes(&s
, sessid
, 20);
4123 SHA_Final(&s
, keyspace
);
4124 /* Next 20 bytes. */
4126 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4128 SHA_Bytes(&s
, H
, 20);
4129 SHA_Bytes(&s
, keyspace
, 20);
4130 SHA_Final(&s
, keyspace
+ 20);
4134 * Handle the SSH2 transport layer.
4136 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
4138 struct do_ssh2_transport_state
{
4139 int nbits
, pbits
, warn
;
4140 Bignum p
, g
, e
, f
, K
;
4141 int kex_init_value
, kex_reply_value
;
4142 const struct ssh_mac
**maclist
;
4144 const struct ssh2_cipher
*cscipher_tobe
;
4145 const struct ssh2_cipher
*sccipher_tobe
;
4146 const struct ssh_mac
*csmac_tobe
;
4147 const struct ssh_mac
*scmac_tobe
;
4148 const struct ssh_compress
*cscomp_tobe
;
4149 const struct ssh_compress
*sccomp_tobe
;
4150 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4151 int hostkeylen
, siglen
;
4152 void *hkey
; /* actual host key */
4153 unsigned char exchange_hash
[20];
4154 int n_preferred_ciphers
;
4155 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
4156 const struct ssh_compress
*preferred_comp
;
4159 crState(do_ssh2_transport_state
);
4161 crBegin(ssh
->do_ssh2_transport_crstate
);
4163 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
4164 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
4165 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
4173 * Set up the preferred ciphers. (NULL => warn below here)
4175 s
->n_preferred_ciphers
= 0;
4176 for (i
= 0; i
< CIPHER_MAX
; i
++) {
4177 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
4178 case CIPHER_BLOWFISH
:
4179 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
4182 if (ssh
->cfg
.ssh2_des_cbc
) {
4183 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
4187 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
4190 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
4193 /* Flag for later. Don't bother if it's the last in
4195 if (i
< CIPHER_MAX
- 1) {
4196 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
4204 * Set up preferred compression.
4206 if (ssh
->cfg
.compression
)
4207 s
->preferred_comp
= &ssh_zlib
;
4209 s
->preferred_comp
= &ssh_comp_none
;
4212 * Be prepared to work around the buggy MAC problem.
4214 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
4215 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
4217 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
4221 int i
, j
, cipherstr_started
;
4224 * Construct and send our key exchange packet.
4226 ssh2_pkt_init(ssh
, SSH2_MSG_KEXINIT
);
4227 for (i
= 0; i
< 16; i
++)
4228 ssh2_pkt_addbyte(ssh
, (unsigned char) random_byte());
4229 /* List key exchange algorithms. */
4230 ssh2_pkt_addstring_start(ssh
);
4231 for (i
= 0; i
< lenof(kex_algs
); i
++) {
4232 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
4233 (ssh
->remote_bugs
& BUG_SSH2_DH_GEX
))
4235 ssh2_pkt_addstring_str(ssh
, kex_algs
[i
]->name
);
4236 if (i
< lenof(kex_algs
) - 1)
4237 ssh2_pkt_addstring_str(ssh
, ",");
4239 /* List server host key algorithms. */
4240 ssh2_pkt_addstring_start(ssh
);
4241 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4242 ssh2_pkt_addstring_str(ssh
, hostkey_algs
[i
]->name
);
4243 if (i
< lenof(hostkey_algs
) - 1)
4244 ssh2_pkt_addstring_str(ssh
, ",");
4246 /* List client->server encryption algorithms. */
4247 ssh2_pkt_addstring_start(ssh
);
4248 cipherstr_started
= 0;
4249 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4250 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4251 if (!c
) continue; /* warning flag */
4252 for (j
= 0; j
< c
->nciphers
; j
++) {
4253 if (cipherstr_started
)
4254 ssh2_pkt_addstring_str(ssh
, ",");
4255 ssh2_pkt_addstring_str(ssh
, c
->list
[j
]->name
);
4256 cipherstr_started
= 1;
4259 /* List server->client encryption algorithms. */
4260 ssh2_pkt_addstring_start(ssh
);
4261 cipherstr_started
= 0;
4262 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4263 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4264 if (!c
) continue; /* warning flag */
4265 for (j
= 0; j
< c
->nciphers
; j
++) {
4266 if (cipherstr_started
)
4267 ssh2_pkt_addstring_str(ssh
, ",");
4268 ssh2_pkt_addstring_str(ssh
, c
->list
[j
]->name
);
4269 cipherstr_started
= 1;
4272 /* List client->server MAC algorithms. */
4273 ssh2_pkt_addstring_start(ssh
);
4274 for (i
= 0; i
< s
->nmacs
; i
++) {
4275 ssh2_pkt_addstring_str(ssh
, s
->maclist
[i
]->name
);
4276 if (i
< s
->nmacs
- 1)
4277 ssh2_pkt_addstring_str(ssh
, ",");
4279 /* List server->client MAC algorithms. */
4280 ssh2_pkt_addstring_start(ssh
);
4281 for (i
= 0; i
< s
->nmacs
; i
++) {
4282 ssh2_pkt_addstring_str(ssh
, s
->maclist
[i
]->name
);
4283 if (i
< s
->nmacs
- 1)
4284 ssh2_pkt_addstring_str(ssh
, ",");
4286 /* List client->server compression algorithms. */
4287 ssh2_pkt_addstring_start(ssh
);
4288 assert(lenof(compressions
) > 1);
4289 ssh2_pkt_addstring_str(ssh
, s
->preferred_comp
->name
);
4290 for (i
= 0; i
< lenof(compressions
); i
++) {
4291 const struct ssh_compress
*c
= compressions
[i
];
4292 if (c
!= s
->preferred_comp
) {
4293 ssh2_pkt_addstring_str(ssh
, ",");
4294 ssh2_pkt_addstring_str(ssh
, c
->name
);
4297 /* List server->client compression algorithms. */
4298 ssh2_pkt_addstring_start(ssh
);
4299 assert(lenof(compressions
) > 1);
4300 ssh2_pkt_addstring_str(ssh
, s
->preferred_comp
->name
);
4301 for (i
= 0; i
< lenof(compressions
); i
++) {
4302 const struct ssh_compress
*c
= compressions
[i
];
4303 if (c
!= s
->preferred_comp
) {
4304 ssh2_pkt_addstring_str(ssh
, ",");
4305 ssh2_pkt_addstring_str(ssh
, c
->name
);
4308 /* List client->server languages. Empty list. */
4309 ssh2_pkt_addstring_start(ssh
);
4310 /* List server->client languages. Empty list. */
4311 ssh2_pkt_addstring_start(ssh
);
4312 /* First KEX packet does _not_ follow, because we're not that brave. */
4313 ssh2_pkt_addbool(ssh
, FALSE
);
4315 ssh2_pkt_adduint32(ssh
, 0);
4318 ssh
->exhash
= ssh
->exhashbase
;
4319 sha_string(&ssh
->exhash
, ssh
->pktout
.data
+ 5, ssh
->pktout
.length
- 5);
4325 if (ssh
->pktin
.length
> 5)
4326 sha_string(&ssh
->exhash
, ssh
->pktin
.data
+ 5, ssh
->pktin
.length
- 5);
4329 * Now examine the other side's KEXINIT to see what we're up
4336 if (ssh
->pktin
.type
!= SSH2_MSG_KEXINIT
) {
4337 bombout(("expected key exchange packet from server"));
4341 ssh
->hostkey
= NULL
;
4342 s
->cscipher_tobe
= NULL
;
4343 s
->sccipher_tobe
= NULL
;
4344 s
->csmac_tobe
= NULL
;
4345 s
->scmac_tobe
= NULL
;
4346 s
->cscomp_tobe
= NULL
;
4347 s
->sccomp_tobe
= NULL
;
4348 ssh
->pktin
.savedpos
+= 16; /* skip garbage cookie */
4349 ssh_pkt_getstring(ssh
, &str
, &len
); /* key exchange algorithms */
4350 for (i
= 0; i
< lenof(kex_algs
); i
++) {
4351 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
4352 (ssh
->remote_bugs
& BUG_SSH2_DH_GEX
))
4354 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
4355 ssh
->kex
= kex_algs
[i
];
4359 ssh_pkt_getstring(ssh
, &str
, &len
); /* host key algorithms */
4360 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4361 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
4362 ssh
->hostkey
= hostkey_algs
[i
];
4366 ssh_pkt_getstring(ssh
, &str
, &len
); /* client->server cipher */
4368 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4369 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4373 for (j
= 0; j
< c
->nciphers
; j
++) {
4374 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4375 s
->cscipher_tobe
= c
->list
[j
];
4380 if (s
->cscipher_tobe
) {
4382 askcipher(ssh
->frontend
, s
->cscipher_tobe
->name
, 1);
4386 if (!s
->cscipher_tobe
) {
4387 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
4388 str ? str
: "(null)"));
4392 ssh_pkt_getstring(ssh
, &str
, &len
); /* server->client cipher */
4394 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4395 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4399 for (j
= 0; j
< c
->nciphers
; j
++) {
4400 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4401 s
->sccipher_tobe
= c
->list
[j
];
4406 if (s
->sccipher_tobe
) {
4408 askcipher(ssh
->frontend
, s
->sccipher_tobe
->name
, 2);
4412 if (!s
->sccipher_tobe
) {
4413 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
4414 str ? str
: "(null)"));
4418 ssh_pkt_getstring(ssh
, &str
, &len
); /* client->server mac */
4419 for (i
= 0; i
< s
->nmacs
; i
++) {
4420 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4421 s
->csmac_tobe
= s
->maclist
[i
];
4425 ssh_pkt_getstring(ssh
, &str
, &len
); /* server->client mac */
4426 for (i
= 0; i
< s
->nmacs
; i
++) {
4427 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4428 s
->scmac_tobe
= s
->maclist
[i
];
4432 ssh_pkt_getstring(ssh
, &str
, &len
); /* client->server compression */
4433 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4434 const struct ssh_compress
*c
=
4435 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4436 if (in_commasep_string(c
->name
, str
, len
)) {
4441 ssh_pkt_getstring(ssh
, &str
, &len
); /* server->client compression */
4442 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4443 const struct ssh_compress
*c
=
4444 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4445 if (in_commasep_string(c
->name
, str
, len
)) {
4453 * Work out the number of bits of key we will need from the key
4454 * exchange. We start with the maximum key length of either
4460 csbits
= s
->cscipher_tobe
->keylen
;
4461 scbits
= s
->sccipher_tobe
->keylen
;
4462 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
4464 /* The keys only have 160-bit entropy, since they're based on
4465 * a SHA-1 hash. So cap the key size at 160 bits. */
4470 * If we're doing Diffie-Hellman group exchange, start by
4471 * requesting a group.
4473 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4474 logevent("Doing Diffie-Hellman group exchange");
4475 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
4477 * Work out how big a DH group we will need to allow that
4480 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
4481 ssh2_pkt_init(ssh
, SSH2_MSG_KEX_DH_GEX_REQUEST
);
4482 ssh2_pkt_adduint32(ssh
, s
->pbits
);
4486 if (ssh
->pktin
.type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
4487 bombout(("expected key exchange group packet from server"));
4490 s
->p
= ssh2_pkt_getmp(ssh
);
4491 s
->g
= ssh2_pkt_getmp(ssh
);
4492 ssh
->kex_ctx
= dh_setup_group(s
->p
, s
->g
);
4493 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
4494 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
4496 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP1
;
4497 ssh
->kex_ctx
= dh_setup_group1();
4498 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
4499 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
4502 logevent("Doing Diffie-Hellman key exchange");
4504 * Now generate and send e for Diffie-Hellman.
4506 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
4507 ssh2_pkt_init(ssh
, s
->kex_init_value
);
4508 ssh2_pkt_addmp(ssh
, s
->e
);
4512 if (ssh
->pktin
.type
!= s
->kex_reply_value
) {
4513 bombout(("expected key exchange reply packet from server"));
4516 ssh_pkt_getstring(ssh
, &s
->hostkeydata
, &s
->hostkeylen
);
4517 s
->f
= ssh2_pkt_getmp(ssh
);
4518 ssh_pkt_getstring(ssh
, &s
->sigdata
, &s
->siglen
);
4520 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
4522 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
4523 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4524 sha_uint32(&ssh
->exhash
, s
->pbits
);
4525 sha_mpint(&ssh
->exhash
, s
->p
);
4526 sha_mpint(&ssh
->exhash
, s
->g
);
4528 sha_mpint(&ssh
->exhash
, s
->e
);
4529 sha_mpint(&ssh
->exhash
, s
->f
);
4530 sha_mpint(&ssh
->exhash
, s
->K
);
4531 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
4533 dh_cleanup(ssh
->kex_ctx
);
4534 ssh
->kex_ctx
= NULL
;
4537 debug(("Exchange hash is:\n"));
4538 dmemdump(s
->exchange_hash
, 20);
4541 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
4543 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
4544 (char *)s
->exchange_hash
, 20)) {
4545 bombout(("Server's host key did not match the signature supplied"));
4550 * Authenticate remote host: verify host key. (We've already
4551 * checked the signature of the exchange hash.)
4553 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
4554 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
4555 verify_ssh_host_key(ssh
->frontend
,
4556 ssh
->savedhost
, ssh
->savedport
, ssh
->hostkey
->keytype
,
4557 s
->keystr
, s
->fingerprint
);
4558 if (s
->first_kex
) { /* don't bother logging this in rekeys */
4559 logevent("Host key fingerprint is:");
4560 logevent(s
->fingerprint
);
4562 sfree(s
->fingerprint
);
4564 ssh
->hostkey
->freekey(s
->hkey
);
4567 * Send SSH2_MSG_NEWKEYS.
4569 ssh2_pkt_init(ssh
, SSH2_MSG_NEWKEYS
);
4573 * Expect SSH2_MSG_NEWKEYS from server.
4576 if (ssh
->pktin
.type
!= SSH2_MSG_NEWKEYS
) {
4577 bombout(("expected new-keys packet from server"));
4582 * Create and initialise session keys.
4584 if (ssh
->cs_cipher_ctx
)
4585 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
4586 ssh
->cscipher
= s
->cscipher_tobe
;
4587 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
4589 if (ssh
->sc_cipher_ctx
)
4590 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
4591 ssh
->sccipher
= s
->sccipher_tobe
;
4592 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
4594 if (ssh
->cs_mac_ctx
)
4595 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
4596 ssh
->csmac
= s
->csmac_tobe
;
4597 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
4599 if (ssh
->sc_mac_ctx
)
4600 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
4601 ssh
->scmac
= s
->scmac_tobe
;
4602 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
4604 if (ssh
->cs_comp_ctx
)
4605 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
4606 ssh
->cscomp
= s
->cscomp_tobe
;
4607 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
4609 if (ssh
->sc_comp_ctx
)
4610 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
4611 ssh
->sccomp
= s
->sccomp_tobe
;
4612 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
4615 * Set IVs after keys. Here we use the exchange hash from the
4616 * _first_ key exchange.
4619 unsigned char keyspace
[40];
4621 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
4622 sizeof(s
->exchange_hash
));
4623 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
4624 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
4625 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
4626 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
4627 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
4628 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
4629 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
4630 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
4631 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
4632 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
4633 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
4634 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
4636 logeventf(ssh
, "Initialised %.200s client->server encryption",
4637 ssh
->cscipher
->text_name
);
4638 logeventf(ssh
, "Initialised %.200s server->client encryption",
4639 ssh
->sccipher
->text_name
);
4640 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
4641 ssh
->csmac
->text_name
);
4642 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
4643 ssh
->scmac
->text_name
);
4644 if (ssh
->cscomp
->text_name
)
4645 logeventf(ssh
, "Initialised %s compression",
4646 ssh
->cscomp
->text_name
);
4647 if (ssh
->sccomp
->text_name
)
4648 logeventf(ssh
, "Initialised %s decompression",
4649 ssh
->sccomp
->text_name
);
4652 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4658 * If this is the first key exchange phase, we must pass the
4659 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
4660 * wants to see it but because it will need time to initialise
4661 * itself before it sees an actual packet. In subsequent key
4662 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
4663 * it would only confuse the layer above.
4665 if (!s
->first_kex
) {
4671 * Now we're encrypting. Begin returning 1 to the protocol main
4672 * function so that other things can run on top of the
4673 * transport. If we ever see a KEXINIT, we must go back to the
4676 while (!(ispkt
&& ssh
->pktin
.type
== SSH2_MSG_KEXINIT
)) {
4679 logevent("Server initiated key re-exchange");
4680 goto begin_key_exchange
;
4686 * Add data to an SSH2 channel output buffer.
4688 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
4691 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
4695 * Attempt to send data on an SSH2 channel.
4697 static int ssh2_try_send(struct ssh_channel
*c
)
4701 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
4704 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
4705 if ((unsigned)len
> c
->v
.v2
.remwindow
)
4706 len
= c
->v
.v2
.remwindow
;
4707 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
4708 len
= c
->v
.v2
.remmaxpkt
;
4709 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_DATA
);
4710 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
4711 dont_log_data(ssh
, PKTLOG_OMIT
);
4712 ssh2_pkt_addstring_start(ssh
);
4713 ssh2_pkt_addstring_data(ssh
, data
, len
);
4714 end_log_omission(ssh
);
4716 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
4717 c
->v
.v2
.remwindow
-= len
;
4721 * After having sent as much data as we can, return the amount
4724 return bufchain_size(&c
->v
.v2
.outbuffer
);
4728 * Potentially enlarge the window on an SSH2 channel.
4730 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
4735 * Never send WINDOW_ADJUST for a channel that the remote side
4736 * already thinks it's closed; there's no point, since it won't
4737 * be sending any more data anyway.
4742 if (newwin
> c
->v
.v2
.locwindow
) {
4743 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4744 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
4745 ssh2_pkt_adduint32(ssh
, newwin
- c
->v
.v2
.locwindow
);
4747 c
->v
.v2
.locwindow
= newwin
;
4752 * Handle the SSH2 userauth and connection layers.
4754 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
4756 struct do_ssh2_authconn_state
{
4758 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
4760 AUTH_KEYBOARD_INTERACTIVE
4764 AUTH_TYPE_PUBLICKEY
,
4765 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
4766 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
4768 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
4769 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4771 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
4772 int tried_pubkey_config
, tried_agent
, tried_keyb_inter
;
4773 int kbd_inter_running
;
4775 int num_prompts
, curr_prompt
, echo
;
4780 void *publickey_blob
;
4781 int publickey_bloblen
;
4782 unsigned char request
[5], *response
, *p
;
4786 char *pkblob
, *alg
, *commentp
;
4787 int pklen
, alglen
, commentlen
;
4788 int siglen
, retlen
, len
;
4789 char *q
, *agentreq
, *ret
;
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"); /* FIXME */
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 logevent("Opened channel for session");
5650 ssh
->mainchan
= NULL
;
5653 * Potentially enable X11 forwarding.
5655 if (ssh
->mainchan
&& ssh
->cfg
.x11_forward
) {
5656 char proto
[20], data
[64];
5657 logevent("Requesting X11 forwarding");
5658 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
5659 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
5660 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
5661 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5662 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
5663 ssh2_pkt_addstring(ssh
, "x11-req");
5664 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5665 ssh2_pkt_addbool(ssh
, 0); /* many connections */
5666 ssh2_pkt_addstring(ssh
, proto
);
5667 ssh2_pkt_addstring(ssh
, data
);
5668 ssh2_pkt_adduint32(ssh
, x11_get_screen_number(ssh
->cfg
.x11_display
));
5672 crWaitUntilV(ispkt
);
5673 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5674 unsigned i
= ssh_pkt_getuint32(ssh
);
5675 struct ssh_channel
*c
;
5676 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5678 continue; /* nonexistent channel */
5679 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
5681 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5683 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5684 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5685 bombout(("Unexpected response to X11 forwarding request:"
5686 " packet type %d", ssh
->pktin
.type
));
5689 logevent("X11 forwarding refused");
5691 logevent("X11 forwarding enabled");
5692 ssh
->X11_fwd_enabled
= TRUE
;
5697 * Enable port forwardings.
5702 int sport
,dport
,sserv
,dserv
;
5703 char sports
[256], dports
[256], saddr
[256], host
[256];
5705 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
5706 /* Add port forwardings. */
5707 ssh
->portfwd_strptr
= ssh
->cfg
.portfwd
;
5708 while (*ssh
->portfwd_strptr
) {
5709 type
= *ssh
->portfwd_strptr
++;
5712 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= '\t') {
5713 if (*ssh
->portfwd_strptr
== ':') {
5715 * We've seen a colon in the middle of the
5716 * source port number. This means that
5717 * everything we've seen until now is the
5718 * source _address_, so we'll move it into
5719 * saddr and start sports from the beginning
5722 ssh
->portfwd_strptr
++;
5724 strcpy(saddr
, sports
);
5727 if (n
< 255) sports
[n
++] = *ssh
->portfwd_strptr
++;
5731 if (*ssh
->portfwd_strptr
== '\t')
5732 ssh
->portfwd_strptr
++;
5734 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= ':') {
5735 if (n
< 255) host
[n
++] = *ssh
->portfwd_strptr
++;
5738 if (*ssh
->portfwd_strptr
== ':')
5739 ssh
->portfwd_strptr
++;
5741 while (*ssh
->portfwd_strptr
) {
5742 if (n
< 255) dports
[n
++] = *ssh
->portfwd_strptr
++;
5745 ssh
->portfwd_strptr
++;
5746 dport
= atoi(dports
);
5750 dport
= net_service_lookup(dports
);
5752 logeventf(ssh
, "Service lookup failed for destination"
5753 " port \"%s\"", dports
);
5757 while (*ssh
->portfwd_strptr
) ssh
->portfwd_strptr
++;
5759 ssh
->portfwd_strptr
++; /* eat the NUL and move to next one */
5761 sport
= atoi(sports
);
5765 sport
= net_service_lookup(sports
);
5767 logeventf(ssh
, "Service lookup failed for source"
5768 " port \"%s\"", sports
);
5771 if (sport
&& dport
) {
5772 /* Set up a description of the source port. */
5773 char *sportdesc
= dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
5774 (int)(*saddr?
strlen(saddr
):0), *saddr?saddr
:NULL
,
5775 (int)(*saddr?
1:0), ":",
5776 (int)(sserv ?
strlen(sports
) : 0), sports
,
5777 sserv
, "(", sport
, sserv
, ")");
5779 /* Verbose description of the destination port */
5780 char *dportdesc
= dupprintf("%s:%.*s%.*s%d%.*s",
5782 (int)(dserv ?
strlen(dports
) : 0), dports
,
5783 dserv
, "(", dport
, dserv
, ")");
5784 const char *err
= pfd_addforward(host
, dport
,
5785 *saddr ? saddr
: NULL
,
5786 sport
, ssh
, &ssh
->cfg
);
5788 logeventf(ssh
, "Local port %s forward to %s"
5789 " failed: %s", sportdesc
, dportdesc
, err
);
5791 logeventf(ssh
, "Local port %s forwarding to %s",
5792 sportdesc
, dportdesc
);
5795 } else if (type
== 'D') {
5796 const char *err
= pfd_addforward(NULL
, -1,
5797 *saddr ? saddr
: NULL
,
5798 sport
, ssh
, &ssh
->cfg
);
5800 logeventf(ssh
, "Local port %s SOCKS dynamic forward"
5801 " setup failed: %s", sportdesc
, err
);
5803 logeventf(ssh
, "Local port %s doing SOCKS"
5804 " dynamic forwarding", sportdesc
);
5807 struct ssh_rportfwd
*pf
;
5808 pf
= snew(struct ssh_rportfwd
);
5809 strcpy(pf
->dhost
, host
);
5812 if (add234(ssh
->rportfwds
, pf
) != pf
) {
5813 logeventf(ssh
, "Duplicate remote port forwarding"
5814 " to %s:%d", host
, dport
);
5817 logeventf(ssh
, "Requesting remote port %s"
5818 " forward to %s:%.*s%.*s%d%.*s",
5821 (int)(dserv ?
strlen(dports
) : 0), dports
,
5822 dserv
, "(", dport
, dserv
, ")");
5823 ssh2_pkt_init(ssh
, SSH2_MSG_GLOBAL_REQUEST
);
5824 ssh2_pkt_addstring(ssh
, "tcpip-forward");
5825 ssh2_pkt_addbool(ssh
, 1);/* want reply */
5827 ssh2_pkt_addstring(ssh
, saddr
);
5828 if (ssh
->cfg
.rport_acceptall
)
5829 ssh2_pkt_addstring(ssh
, "0.0.0.0");
5831 ssh2_pkt_addstring(ssh
, "127.0.0.1");
5832 ssh2_pkt_adduint32(ssh
, sport
);
5836 crWaitUntilV(ispkt
);
5837 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5838 unsigned i
= ssh_pkt_getuint32(ssh
);
5839 struct ssh_channel
*c
;
5840 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5842 continue;/* nonexistent channel */
5843 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
5845 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5847 if (ssh
->pktin
.type
!= SSH2_MSG_REQUEST_SUCCESS
) {
5848 if (ssh
->pktin
.type
!= SSH2_MSG_REQUEST_FAILURE
) {
5849 bombout(("Unexpected response to port "
5850 "forwarding request: packet type %d",
5854 logevent("Server refused this port forwarding");
5856 logevent("Remote port forwarding enabled");
5866 * Potentially enable agent forwarding.
5868 if (ssh
->mainchan
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
5869 logevent("Requesting OpenSSH-style agent forwarding");
5870 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5871 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
5872 ssh2_pkt_addstring(ssh
, "auth-agent-req@openssh.com");
5873 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5877 crWaitUntilV(ispkt
);
5878 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5879 unsigned i
= ssh_pkt_getuint32(ssh
);
5880 struct ssh_channel
*c
;
5881 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5883 continue; /* nonexistent channel */
5884 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
5886 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5888 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5889 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5890 bombout(("Unexpected response to agent forwarding request:"
5891 " packet type %d", ssh
->pktin
.type
));
5894 logevent("Agent forwarding refused");
5896 logevent("Agent forwarding enabled");
5897 ssh
->agentfwd_enabled
= TRUE
;
5902 * Now allocate a pty for the session.
5904 if (ssh
->mainchan
&& !ssh
->cfg
.nopty
) {
5905 /* Unpick the terminal-speed string. */
5906 /* XXX perhaps we should allow no speeds to be sent. */
5907 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
5908 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
5909 /* Build the pty request. */
5910 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5911 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
); /* recipient channel */
5912 ssh2_pkt_addstring(ssh
, "pty-req");
5913 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5914 ssh2_pkt_addstring(ssh
, ssh
->cfg
.termtype
);
5915 ssh2_pkt_adduint32(ssh
, ssh
->term_width
);
5916 ssh2_pkt_adduint32(ssh
, ssh
->term_height
);
5917 ssh2_pkt_adduint32(ssh
, 0); /* pixel width */
5918 ssh2_pkt_adduint32(ssh
, 0); /* pixel height */
5919 ssh2_pkt_addstring_start(ssh
);
5920 ssh2_pkt_addbyte(ssh
, 128); /* TTY_OP_ISPEED */
5921 ssh2_pkt_adduint32(ssh
, ssh
->ispeed
);
5922 ssh2_pkt_addbyte(ssh
, 129); /* TTY_OP_OSPEED */
5923 ssh2_pkt_adduint32(ssh
, ssh
->ospeed
);
5924 ssh2_pkt_addstring_data(ssh
, "\0", 1); /* TTY_OP_END */
5926 ssh
->state
= SSH_STATE_INTERMED
;
5929 crWaitUntilV(ispkt
);
5930 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5931 unsigned i
= ssh_pkt_getuint32(ssh
);
5932 struct ssh_channel
*c
;
5933 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5935 continue; /* nonexistent channel */
5936 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
5938 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5940 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5941 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5942 bombout(("Unexpected response to pty request:"
5943 " packet type %d", ssh
->pktin
.type
));
5946 c_write_str(ssh
, "Server refused to allocate pty\r\n");
5947 ssh
->editing
= ssh
->echoing
= 1;
5949 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
5950 ssh
->ospeed
, ssh
->ispeed
);
5953 ssh
->editing
= ssh
->echoing
= 1;
5957 * Start a shell or a remote command. We may have to attempt
5958 * this twice if the config data has provided a second choice
5961 if (ssh
->mainchan
) while (1) {
5965 if (ssh
->fallback_cmd
) {
5966 subsys
= ssh
->cfg
.ssh_subsys2
;
5967 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
5969 subsys
= ssh
->cfg
.ssh_subsys
;
5970 cmd
= ssh
->cfg
.remote_cmd_ptr
;
5973 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5974 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
); /* recipient channel */
5976 ssh2_pkt_addstring(ssh
, "subsystem");
5977 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5978 ssh2_pkt_addstring(ssh
, cmd
);
5980 ssh2_pkt_addstring(ssh
, "exec");
5981 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5982 ssh2_pkt_addstring(ssh
, cmd
);
5984 ssh2_pkt_addstring(ssh
, "shell");
5985 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5989 crWaitUntilV(ispkt
);
5990 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5991 unsigned i
= ssh_pkt_getuint32(ssh
);
5992 struct ssh_channel
*c
;
5993 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5995 continue; /* nonexistent channel */
5996 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
5998 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5999 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6000 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6001 bombout(("Unexpected response to shell/command request:"
6002 " packet type %d", ssh
->pktin
.type
));
6006 * We failed to start the command. If this is the
6007 * fallback command, we really are finished; if it's
6008 * not, and if the fallback command exists, try falling
6009 * back to it before complaining.
6011 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
6012 logevent("Primary command failed; attempting fallback");
6013 ssh
->fallback_cmd
= TRUE
;
6016 bombout(("Server refused to start a shell/command"));
6019 logevent("Started a shell/command");
6024 ssh
->state
= SSH_STATE_SESSION
;
6025 if (ssh
->size_needed
)
6026 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
6027 if (ssh
->eof_needed
)
6028 ssh_special(ssh
, TS_EOF
);
6034 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
6039 s
->try_send
= FALSE
;
6041 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
6042 ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
6045 unsigned i
= ssh_pkt_getuint32(ssh
);
6046 struct ssh_channel
*c
;
6047 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6049 continue; /* nonexistent channel */
6050 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
6051 ssh_pkt_getuint32(ssh
) != SSH2_EXTENDED_DATA_STDERR
)
6052 continue; /* extended but not stderr */
6053 ssh_pkt_getstring(ssh
, &data
, &length
);
6056 c
->v
.v2
.locwindow
-= length
;
6058 case CHAN_MAINSESSION
:
6060 from_backend(ssh
->frontend
, ssh
->pktin
.type
==
6061 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
6065 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
6068 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
6071 while (length
> 0) {
6072 if (c
->u
.a
.lensofar
< 4) {
6073 int l
= min(4 - c
->u
.a
.lensofar
, length
);
6074 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
6078 c
->u
.a
.lensofar
+= l
;
6080 if (c
->u
.a
.lensofar
== 4) {
6082 4 + GET_32BIT(c
->u
.a
.msglen
);
6083 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
6085 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
6087 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
6089 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
6091 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
6095 c
->u
.a
.lensofar
+= l
;
6097 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
6100 if (agent_query(c
->u
.a
.message
,
6103 ssh_agentf_callback
, c
))
6104 ssh_agentf_callback(c
, reply
, replylen
);
6105 sfree(c
->u
.a
.message
);
6106 c
->u
.a
.lensofar
= 0;
6113 * If we are not buffering too much data,
6114 * enlarge the window again at the remote side.
6116 if (bufsize
< OUR_V2_WINSIZE
)
6117 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
6119 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
6120 unsigned i
= ssh_pkt_getuint32(ssh
);
6121 struct ssh_channel
*c
;
6123 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6125 continue; /* nonexistent channel */
6127 if (c
->type
== CHAN_X11
) {
6129 * Remote EOF on an X11 channel means we should
6130 * wrap up and close the channel ourselves.
6132 x11_close(c
->u
.x11
.s
);
6134 } else if (c
->type
== CHAN_AGENT
) {
6136 } else if (c
->type
== CHAN_SOCKDATA
) {
6137 pfd_close(c
->u
.pfd
.s
);
6140 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
6141 unsigned i
= ssh_pkt_getuint32(ssh
);
6142 struct ssh_channel
*c
;
6144 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6145 if (!c
|| ((int)c
->remoteid
) == -1) {
6146 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
6147 c ?
"half-open" : "nonexistent", i
));
6150 /* Do pre-close processing on the channel. */
6152 case CHAN_MAINSESSION
:
6153 break; /* nothing to see here, move along */
6155 if (c
->u
.x11
.s
!= NULL
)
6156 x11_close(c
->u
.x11
.s
);
6163 if (c
->u
.pfd
.s
!= NULL
)
6164 pfd_close(c
->u
.pfd
.s
);
6168 if (c
->closes
== 0) {
6169 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_CLOSE
);
6170 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
6173 del234(ssh
->channels
, c
);
6174 bufchain_clear(&c
->v
.v2
.outbuffer
);
6178 * See if that was the last channel left open.
6179 * (This is only our termination condition if we're
6180 * not running in -N mode.)
6182 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
6183 logevent("All channels closed. Disconnecting");
6186 * We used to send SSH_MSG_DISCONNECT here,
6187 * because I'd believed that _every_ conforming
6188 * SSH2 connection had to end with a disconnect
6189 * being sent by at least one side; apparently
6190 * I was wrong and it's perfectly OK to
6191 * unceremoniously slam the connection shut
6192 * when you're done, and indeed OpenSSH feels
6193 * this is more polite than sending a
6194 * DISCONNECT. So now we don't.
6196 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
6197 ssh2_pkt_adduint32(ssh
, SSH2_DISCONNECT_BY_APPLICATION
);
6198 ssh2_pkt_addstring(ssh
, "All open channels closed");
6199 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
6202 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6205 continue; /* remote sends close; ignore (FIXME) */
6206 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
6207 unsigned i
= ssh_pkt_getuint32(ssh
);
6208 struct ssh_channel
*c
;
6209 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6210 if (!c
|| c
->closes
)
6211 continue; /* nonexistent or closing channel */
6212 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(ssh
);
6214 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
6215 unsigned i
= ssh_pkt_getuint32(ssh
);
6216 struct ssh_channel
*c
;
6217 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6219 continue; /* nonexistent channel */
6220 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
6221 continue; /* dunno why they're confirming this */
6222 c
->remoteid
= ssh_pkt_getuint32(ssh
);
6223 c
->type
= CHAN_SOCKDATA
;
6224 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(ssh
);
6225 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(ssh
);
6227 pfd_confirm(c
->u
.pfd
.s
);
6230 * We have a pending close on this channel,
6231 * which we decided on before the server acked
6232 * the channel open. So now we know the
6233 * remoteid, we can close it again.
6235 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_CLOSE
);
6236 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
6239 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_OPEN_FAILURE
) {
6240 static const char *const reasons
[] = {
6241 "<unknown reason code>",
6242 "Administratively prohibited",
6244 "Unknown channel type",
6245 "Resource shortage",
6247 unsigned i
= ssh_pkt_getuint32(ssh
);
6248 unsigned reason_code
;
6249 char *reason_string
;
6252 struct ssh_channel
*c
;
6253 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
6255 continue; /* nonexistent channel */
6256 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
6257 continue; /* dunno why they're failing this */
6259 reason_code
= ssh_pkt_getuint32(ssh
);
6260 if (reason_code
>= lenof(reasons
))
6261 reason_code
= 0; /* ensure reasons[reason_code] in range */
6262 ssh_pkt_getstring(ssh
, &reason_string
, &reason_length
);
6263 message
= dupprintf("Forwarded connection refused by"
6264 " server: %s [%.*s]", reasons
[reason_code
],
6265 reason_length
, reason_string
);
6269 pfd_close(c
->u
.pfd
.s
);
6271 del234(ssh
->channels
, c
);
6273 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
6276 int typelen
, want_reply
;
6277 struct ssh_channel
*c
;
6279 localid
= ssh_pkt_getuint32(ssh
);
6280 ssh_pkt_getstring(ssh
, &type
, &typelen
);
6281 want_reply
= ssh2_pkt_getbool(ssh
);
6284 * First, check that the channel exists. Otherwise,
6285 * we can instantly disconnect with a rude message.
6287 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
6290 sprintf(buf
, "Received channel request for nonexistent"
6291 " channel %d", localid
);
6293 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
6294 ssh2_pkt_adduint32(ssh
, SSH2_DISCONNECT_BY_APPLICATION
);
6295 ssh2_pkt_addstring(ssh
, buf
);
6296 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
6298 connection_fatal(ssh
->frontend
, "%s", buf
);
6299 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6304 * Having got the channel number, we now look at
6305 * the request type string to see if it's something
6308 if (typelen
== 11 && !memcmp(type
, "exit-status", 11) &&
6309 c
== ssh
->mainchan
) {
6310 /* We recognise "exit-status" on the primary channel. */
6312 ssh
->exitcode
= ssh_pkt_getuint32(ssh
);
6313 sprintf(buf
, "Server sent command exit status %d",
6317 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_SUCCESS
);
6318 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
6323 * This is a channel request we don't know
6324 * about, so we now either ignore the request
6325 * or respond with CHANNEL_FAILURE, depending
6329 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_FAILURE
);
6330 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
6334 } else if (ssh
->pktin
.type
== SSH2_MSG_GLOBAL_REQUEST
) {
6336 int typelen
, want_reply
;
6338 ssh_pkt_getstring(ssh
, &type
, &typelen
);
6339 want_reply
= ssh2_pkt_getbool(ssh
);
6342 * We currently don't support any global requests
6343 * at all, so we either ignore the request or
6344 * respond with REQUEST_FAILURE, depending on
6348 ssh2_pkt_init(ssh
, SSH2_MSG_REQUEST_FAILURE
);
6351 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
6358 struct ssh_channel
*c
;
6359 unsigned remid
, winsize
, pktsize
;
6360 ssh_pkt_getstring(ssh
, &type
, &typelen
);
6361 c
= snew(struct ssh_channel
);
6364 remid
= ssh_pkt_getuint32(ssh
);
6365 winsize
= ssh_pkt_getuint32(ssh
);
6366 pktsize
= ssh_pkt_getuint32(ssh
);
6368 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
6371 ssh_pkt_getstring(ssh
, &peeraddr
, &peeraddrlen
);
6372 addrstr
= snewn(peeraddrlen
+1, char);
6373 memcpy(addrstr
, peeraddr
, peeraddrlen
);
6374 addrstr
[peeraddrlen
] = '\0';
6375 peerport
= ssh_pkt_getuint32(ssh
);
6377 logeventf(ssh
, "Received X11 connect request from %s:%d",
6380 if (!ssh
->X11_fwd_enabled
)
6381 error
= "X11 forwarding is not enabled";
6382 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
6383 ssh
->x11auth
, addrstr
, peerport
,
6384 &ssh
->cfg
) != NULL
) {
6385 error
= "Unable to open an X11 connection";
6387 logevent("Opening X11 forward connection succeeded");
6392 } else if (typelen
== 15 &&
6393 !memcmp(type
, "forwarded-tcpip", 15)) {
6394 struct ssh_rportfwd pf
, *realpf
;
6397 ssh_pkt_getstring(ssh
, &dummy
, &dummylen
);/* skip address */
6398 pf
.sport
= ssh_pkt_getuint32(ssh
);
6399 ssh_pkt_getstring(ssh
, &peeraddr
, &peeraddrlen
);
6400 peerport
= ssh_pkt_getuint32(ssh
);
6401 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
6402 logeventf(ssh
, "Received remote port %d open request "
6403 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
6404 if (realpf
== NULL
) {
6405 error
= "Remote port is not recognised";
6407 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
6411 logeventf(ssh
, "Attempting to forward remote port to "
6412 "%s:%d", realpf
->dhost
, realpf
->dport
);
6414 logeventf(ssh
, "Port open failed: %s", e
);
6415 error
= "Port open failed";
6417 logevent("Forwarded port opened successfully");
6418 c
->type
= CHAN_SOCKDATA
;
6421 } else if (typelen
== 22 &&
6422 !memcmp(type
, "auth-agent@openssh.com", 3)) {
6423 if (!ssh
->agentfwd_enabled
)
6424 error
= "Agent forwarding is not enabled";
6426 c
->type
= CHAN_AGENT
; /* identify channel type */
6427 c
->u
.a
.lensofar
= 0;
6430 error
= "Unsupported channel type requested";
6433 c
->remoteid
= remid
;
6435 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN_FAILURE
);
6436 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
6437 ssh2_pkt_adduint32(ssh
, SSH2_OPEN_CONNECT_FAILED
);
6438 ssh2_pkt_addstring(ssh
, error
);
6439 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
6441 logeventf(ssh
, "Rejected channel open: %s", error
);
6444 c
->localid
= alloc_channel_id(ssh
);
6446 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6447 c
->v
.v2
.remwindow
= winsize
;
6448 c
->v
.v2
.remmaxpkt
= pktsize
;
6449 bufchain_init(&c
->v
.v2
.outbuffer
);
6450 add234(ssh
->channels
, c
);
6451 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
6452 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
6453 ssh2_pkt_adduint32(ssh
, c
->localid
);
6454 ssh2_pkt_adduint32(ssh
, c
->v
.v2
.locwindow
);
6455 ssh2_pkt_adduint32(ssh
, 0x4000UL
); /* our max pkt size */
6459 bombout(("Strange packet received: type %d", ssh
->pktin
.type
));
6462 } else if (ssh
->mainchan
) {
6464 * We have spare data. Add it to the channel buffer.
6466 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
6471 struct ssh_channel
*c
;
6473 * Try to send data on all channels if we can.
6475 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
6478 continue; /* don't send on closing channels */
6479 bufsize
= ssh2_try_send(c
);
6482 case CHAN_MAINSESSION
:
6483 /* stdin need not receive an unthrottle
6484 * notification since it will be polled */
6487 x11_unthrottle(c
->u
.x11
.s
);
6490 /* agent sockets are request/response and need no
6491 * buffer management */
6494 pfd_unthrottle(c
->u
.pfd
.s
);
6506 * Handle the top-level SSH2 protocol.
6508 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
6510 if (do_ssh2_transport(ssh
, in
, inlen
, ispkt
) == 0)
6512 do_ssh2_authconn(ssh
, in
, inlen
, ispkt
);
6516 * Called to set up the connection.
6518 * Returns an error message, or NULL on success.
6520 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
6522 char *host
, int port
, char **realhost
, int nodelay
,
6528 ssh
= snew(struct ssh_tag
);
6529 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
6530 ssh
->version
= 0; /* when not ready yet */
6533 ssh
->v1_cipher_ctx
= NULL
;
6534 ssh
->crcda_ctx
= NULL
;
6535 ssh
->cscipher
= NULL
;
6536 ssh
->cs_cipher_ctx
= NULL
;
6537 ssh
->sccipher
= NULL
;
6538 ssh
->sc_cipher_ctx
= NULL
;
6540 ssh
->cs_mac_ctx
= NULL
;
6542 ssh
->sc_mac_ctx
= NULL
;
6544 ssh
->cs_comp_ctx
= NULL
;
6546 ssh
->sc_comp_ctx
= NULL
;
6548 ssh
->kex_ctx
= NULL
;
6549 ssh
->hostkey
= NULL
;
6551 ssh
->state
= SSH_STATE_PREPACKET
;
6552 ssh
->size_needed
= FALSE
;
6553 ssh
->eof_needed
= FALSE
;
6557 static const struct Packet empty
= { 0, 0, NULL
, NULL
, 0 };
6558 ssh
->pktin
= ssh
->pktout
= empty
;
6560 ssh
->deferred_send_data
= NULL
;
6561 ssh
->deferred_len
= 0;
6562 ssh
->deferred_size
= 0;
6563 ssh
->pktout_logmode
= PKTLOG_EMIT
;
6564 ssh
->pktout_nblanks
= 0;
6565 ssh
->pktout_blanks
= NULL
;
6566 ssh
->fallback_cmd
= 0;
6568 ssh
->x11auth
= NULL
;
6569 ssh
->v1_compressing
= FALSE
;
6570 ssh
->v2_outgoing_sequence
= 0;
6571 ssh
->ssh1_rdpkt_crstate
= 0;
6572 ssh
->ssh2_rdpkt_crstate
= 0;
6573 ssh
->do_ssh_init_crstate
= 0;
6574 ssh
->ssh_gotdata_crstate
= 0;
6575 ssh
->ssh1_protocol_crstate
= 0;
6576 ssh
->do_ssh1_login_crstate
= 0;
6577 ssh
->do_ssh2_transport_crstate
= 0;
6578 ssh
->do_ssh2_authconn_crstate
= 0;
6579 ssh
->do_ssh_init_state
= NULL
;
6580 ssh
->do_ssh1_login_state
= NULL
;
6581 ssh
->do_ssh2_transport_state
= NULL
;
6582 ssh
->do_ssh2_authconn_state
= NULL
;
6583 ssh
->mainchan
= NULL
;
6584 ssh
->throttled_all
= 0;
6585 ssh
->v1_stdout_throttling
= 0;
6587 *backend_handle
= ssh
;
6590 if (crypto_startup() == 0)
6591 return "Microsoft high encryption pack not installed!";
6594 ssh
->frontend
= frontend_handle
;
6595 ssh
->term_width
= ssh
->cfg
.width
;
6596 ssh
->term_height
= ssh
->cfg
.height
;
6598 ssh
->channels
= NULL
;
6599 ssh
->rportfwds
= NULL
;
6604 ssh
->v1_throttle_count
= 0;
6605 ssh
->overall_bufsize
= 0;
6606 ssh
->fallback_cmd
= 0;
6608 ssh
->protocol
= NULL
;
6610 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
6617 static void ssh_free(void *handle
)
6619 Ssh ssh
= (Ssh
) handle
;
6620 struct ssh_channel
*c
;
6621 struct ssh_rportfwd
*pf
;
6623 if (ssh
->v1_cipher_ctx
)
6624 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
6625 if (ssh
->cs_cipher_ctx
)
6626 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
6627 if (ssh
->sc_cipher_ctx
)
6628 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
6629 if (ssh
->cs_mac_ctx
)
6630 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
6631 if (ssh
->sc_mac_ctx
)
6632 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
6633 if (ssh
->cs_comp_ctx
) {
6635 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
6637 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
6639 if (ssh
->sc_comp_ctx
) {
6641 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
6643 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
6646 dh_cleanup(ssh
->kex_ctx
);
6647 sfree(ssh
->savedhost
);
6649 if (ssh
->channels
) {
6650 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
6653 if (c
->u
.x11
.s
!= NULL
)
6654 x11_close(c
->u
.x11
.s
);
6657 if (c
->u
.pfd
.s
!= NULL
)
6658 pfd_close(c
->u
.pfd
.s
);
6663 freetree234(ssh
->channels
);
6666 if (ssh
->rportfwds
) {
6667 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
6669 freetree234(ssh
->rportfwds
);
6671 sfree(ssh
->deferred_send_data
);
6673 x11_free_auth(ssh
->x11auth
);
6674 sfree(ssh
->do_ssh_init_state
);
6675 sfree(ssh
->do_ssh1_login_state
);
6676 sfree(ssh
->do_ssh2_transport_state
);
6677 sfree(ssh
->do_ssh2_authconn_state
);
6678 if (ssh
->pktout
.data
) {
6679 sfree(ssh
->pktout
.data
);
6680 ssh
->pktout
.data
= NULL
;
6682 if (ssh
->pktin
.data
) {
6683 sfree(ssh
->pktin
.data
);
6684 ssh
->pktin
.data
= NULL
;
6686 if (ssh
->crcda_ctx
) {
6687 crcda_free_context(ssh
->crcda_ctx
);
6688 ssh
->crcda_ctx
= NULL
;
6696 * Reconfigure the SSH backend.
6698 * Currently, this function does nothing very useful. In future,
6699 * however, we could do some handy things with it. For example, we
6700 * could make the port forwarding configurer active in the Change
6701 * Settings box, and this routine could close down existing
6702 * forwardings and open up new ones in response to changes.
6704 static void ssh_reconfig(void *handle
, Config
*cfg
)
6706 Ssh ssh
= (Ssh
) handle
;
6707 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
6711 * Called to send data down the Telnet connection.
6713 static int ssh_send(void *handle
, char *buf
, int len
)
6715 Ssh ssh
= (Ssh
) handle
;
6717 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
6720 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
6722 return ssh_sendbuffer(ssh
);
6726 * Called to query the current amount of buffered stdin data.
6728 static int ssh_sendbuffer(void *handle
)
6730 Ssh ssh
= (Ssh
) handle
;
6733 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
6737 * If the SSH socket itself has backed up, add the total backup
6738 * size on that to any individual buffer on the stdin channel.
6741 if (ssh
->throttled_all
)
6742 override_value
= ssh
->overall_bufsize
;
6744 if (ssh
->version
== 1) {
6745 return override_value
;
6746 } else if (ssh
->version
== 2) {
6747 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
6748 return override_value
;
6750 return (override_value
+
6751 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
6758 * Called to set the size of the window from SSH's POV.
6760 static void ssh_size(void *handle
, int width
, int height
)
6762 Ssh ssh
= (Ssh
) handle
;
6764 ssh
->term_width
= width
;
6765 ssh
->term_height
= height
;
6767 switch (ssh
->state
) {
6768 case SSH_STATE_BEFORE_SIZE
:
6769 case SSH_STATE_PREPACKET
:
6770 case SSH_STATE_CLOSED
:
6771 break; /* do nothing */
6772 case SSH_STATE_INTERMED
:
6773 ssh
->size_needed
= TRUE
; /* buffer for later */
6775 case SSH_STATE_SESSION
:
6776 if (!ssh
->cfg
.nopty
) {
6777 if (ssh
->version
== 1) {
6778 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
6779 PKT_INT
, ssh
->term_height
,
6780 PKT_INT
, ssh
->term_width
,
6781 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
6782 } else if (ssh
->mainchan
) {
6783 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
6784 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
6785 ssh2_pkt_addstring(ssh
, "window-change");
6786 ssh2_pkt_addbool(ssh
, 0);
6787 ssh2_pkt_adduint32(ssh
, ssh
->term_width
);
6788 ssh2_pkt_adduint32(ssh
, ssh
->term_height
);
6789 ssh2_pkt_adduint32(ssh
, 0);
6790 ssh2_pkt_adduint32(ssh
, 0);
6799 * Return a list of the special codes that make sense in this
6802 static const struct telnet_special
*ssh_get_specials(void *handle
)
6804 Ssh ssh
= (Ssh
) handle
;
6806 if (ssh
->version
== 1) {
6807 static const struct telnet_special ssh1_specials
[] = {
6808 {"IGNORE message", TS_NOP
},
6811 return ssh1_specials
;
6812 } else if (ssh
->version
== 2) {
6813 static const struct telnet_special ssh2_specials
[] = {
6815 {"IGNORE message", TS_NOP
},
6818 return ssh2_specials
;
6824 * Send Telnet special codes. TS_EOF is useful for `plink', so you
6825 * can send an EOF and collect resulting output (e.g. `plink
6828 static void ssh_special(void *handle
, Telnet_Special code
)
6830 Ssh ssh
= (Ssh
) handle
;
6832 if (code
== TS_EOF
) {
6833 if (ssh
->state
!= SSH_STATE_SESSION
) {
6835 * Buffer the EOF in case we are pre-SESSION, so we can
6836 * send it as soon as we reach SESSION.
6839 ssh
->eof_needed
= TRUE
;
6842 if (ssh
->version
== 1) {
6843 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
6844 } else if (ssh
->mainchan
) {
6845 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_EOF
);
6846 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
6849 logevent("Sent EOF message");
6850 } else if (code
== TS_PING
|| code
== TS_NOP
) {
6851 if (ssh
->state
== SSH_STATE_CLOSED
6852 || ssh
->state
== SSH_STATE_PREPACKET
) return;
6853 if (ssh
->version
== 1) {
6854 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
6855 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
6857 ssh2_pkt_init(ssh
, SSH2_MSG_IGNORE
);
6858 ssh2_pkt_addstring_start(ssh
);
6861 } else if (code
== TS_BRK
) {
6862 if (ssh
->state
== SSH_STATE_CLOSED
6863 || ssh
->state
== SSH_STATE_PREPACKET
) return;
6864 if (ssh
->version
== 1) {
6865 logevent("Unable to send BREAK signal in SSH1");
6866 } else if (ssh
->mainchan
) {
6867 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
6868 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
6869 ssh2_pkt_addstring(ssh
, "break");
6870 ssh2_pkt_addbool(ssh
, 0);
6871 ssh2_pkt_adduint32(ssh
, 0); /* default break length */
6879 void *new_sock_channel(void *handle
, Socket s
)
6881 Ssh ssh
= (Ssh
) handle
;
6882 struct ssh_channel
*c
;
6883 c
= snew(struct ssh_channel
);
6887 c
->remoteid
= -1; /* to be set when open confirmed */
6888 c
->localid
= alloc_channel_id(ssh
);
6890 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
6892 bufchain_init(&c
->v
.v2
.outbuffer
);
6893 add234(ssh
->channels
, c
);
6899 * This is called when stdout/stderr (the entity to which
6900 * from_backend sends data) manages to clear some backlog.
6902 static void ssh_unthrottle(void *handle
, int bufsize
)
6904 Ssh ssh
= (Ssh
) handle
;
6905 if (ssh
->version
== 1) {
6906 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
6907 ssh
->v1_stdout_throttling
= 0;
6908 ssh1_throttle(ssh
, -1);
6911 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
6912 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
6916 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
6918 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
6921 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
6923 if (ssh
->version
== 1) {
6924 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
6925 PKT_INT
, c
->localid
,
6928 //PKT_STR, <org:orgport>,
6931 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN
);
6932 ssh2_pkt_addstring(ssh
, "direct-tcpip");
6933 ssh2_pkt_adduint32(ssh
, c
->localid
);
6934 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6935 ssh2_pkt_adduint32(ssh
, c
->v
.v2
.locwindow
);/* our window size */
6936 ssh2_pkt_adduint32(ssh
, 0x4000UL
); /* our max pkt size */
6937 ssh2_pkt_addstring(ssh
, hostname
);
6938 ssh2_pkt_adduint32(ssh
, port
);
6940 * We make up values for the originator data; partly it's
6941 * too much hassle to keep track, and partly I'm not
6942 * convinced the server should be told details like that
6943 * about my local network configuration.
6945 ssh2_pkt_addstring(ssh
, "client-side-connection");
6946 ssh2_pkt_adduint32(ssh
, 0);
6952 static Socket
ssh_socket(void *handle
)
6954 Ssh ssh
= (Ssh
) handle
;
6958 static int ssh_sendok(void *handle
)
6960 Ssh ssh
= (Ssh
) handle
;
6961 return ssh
->send_ok
;
6964 static int ssh_ldisc(void *handle
, int option
)
6966 Ssh ssh
= (Ssh
) handle
;
6967 if (option
== LD_ECHO
)
6968 return ssh
->echoing
;
6969 if (option
== LD_EDIT
)
6970 return ssh
->editing
;
6974 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
6976 Ssh ssh
= (Ssh
) handle
;
6980 static void ssh_provide_logctx(void *handle
, void *logctx
)
6982 Ssh ssh
= (Ssh
) handle
;
6983 ssh
->logctx
= logctx
;
6986 static int ssh_return_exitcode(void *handle
)
6988 Ssh ssh
= (Ssh
) handle
;
6992 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
6996 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
6997 * that fails. This variable is the means by which scp.c can reach
6998 * into the SSH code and find out which one it got.
7000 extern int ssh_fallback_cmd(void *handle
)
7002 Ssh ssh
= (Ssh
) handle
;
7003 return ssh
->fallback_cmd
;
7006 Backend ssh_backend
= {
7016 ssh_return_exitcode
,