17 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
18 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
19 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
20 #define SSH1_CMSG_USER 4 /* 0x4 */
21 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
22 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
23 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
24 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
25 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
26 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
27 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
28 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
29 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
30 #define SSH1_SMSG_FAILURE 15 /* 0xf */
31 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
32 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
33 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
34 #define SSH1_CMSG_EOF 19 /* 0x13 */
35 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
36 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
37 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
38 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
39 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
40 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
41 #define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
42 #define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
43 #define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
44 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
45 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
46 #define SSH1_MSG_IGNORE 32 /* 0x20 */
47 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
48 #define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
49 #define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
50 #define SSH1_MSG_DEBUG 36 /* 0x24 */
51 #define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
52 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
53 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
54 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
55 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
56 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
57 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
59 #define SSH1_AUTH_TIS 5 /* 0x5 */
60 #define SSH1_AUTH_CCARD 16 /* 0x10 */
62 #define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
63 /* Mask for protoflags we will echo back to server if seen */
64 #define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
66 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
67 #define SSH2_MSG_IGNORE 2 /* 0x2 */
68 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
69 #define SSH2_MSG_DEBUG 4 /* 0x4 */
70 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
71 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
72 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
73 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
74 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
75 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
76 #define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
77 #define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
78 #define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
79 #define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
80 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
81 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
82 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
83 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
84 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
85 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
86 #define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
87 #define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
88 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
89 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
90 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
91 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
92 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
93 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
94 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
95 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
96 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
97 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
98 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
99 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
100 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
101 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
104 * Packet type contexts, so that ssh2_pkt_type can correctly decode
105 * the ambiguous type numbers back into the correct type strings.
107 #define SSH2_PKTCTX_DHGROUP 0x0001
108 #define SSH2_PKTCTX_DHGEX 0x0002
109 #define SSH2_PKTCTX_KEX_MASK 0x000F
110 #define SSH2_PKTCTX_PUBLICKEY 0x0010
111 #define SSH2_PKTCTX_PASSWORD 0x0020
112 #define SSH2_PKTCTX_KBDINTER 0x0040
113 #define SSH2_PKTCTX_AUTH_MASK 0x00F0
115 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
116 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
117 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
118 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
119 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
120 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
121 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
122 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
123 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
124 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
125 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
126 #define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
127 #define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
128 #define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
129 #define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
131 static const char *const ssh2_disconnect_reasons
[] = {
133 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
134 "SSH_DISCONNECT_PROTOCOL_ERROR",
135 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
136 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
137 "SSH_DISCONNECT_MAC_ERROR",
138 "SSH_DISCONNECT_COMPRESSION_ERROR",
139 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
140 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
141 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
142 "SSH_DISCONNECT_CONNECTION_LOST",
143 "SSH_DISCONNECT_BY_APPLICATION",
144 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
145 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
146 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
147 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
150 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
151 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
152 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
153 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
155 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
158 * Various remote-bug flags.
160 #define BUG_CHOKES_ON_SSH1_IGNORE 1
161 #define BUG_SSH2_HMAC 2
162 #define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
163 #define BUG_CHOKES_ON_RSA 8
164 #define BUG_SSH2_RSA_PADDING 16
165 #define BUG_SSH2_DERIVEKEY 32
166 #define BUG_SSH2_REKEY 64
167 #define BUG_SSH2_PK_SESSIONID 128
169 #define translate(x) if (type == x) return #x
170 #define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
171 static char *ssh1_pkt_type(int type
)
173 translate(SSH1_MSG_DISCONNECT
);
174 translate(SSH1_SMSG_PUBLIC_KEY
);
175 translate(SSH1_CMSG_SESSION_KEY
);
176 translate(SSH1_CMSG_USER
);
177 translate(SSH1_CMSG_AUTH_RSA
);
178 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE
);
179 translate(SSH1_CMSG_AUTH_RSA_RESPONSE
);
180 translate(SSH1_CMSG_AUTH_PASSWORD
);
181 translate(SSH1_CMSG_REQUEST_PTY
);
182 translate(SSH1_CMSG_WINDOW_SIZE
);
183 translate(SSH1_CMSG_EXEC_SHELL
);
184 translate(SSH1_CMSG_EXEC_CMD
);
185 translate(SSH1_SMSG_SUCCESS
);
186 translate(SSH1_SMSG_FAILURE
);
187 translate(SSH1_CMSG_STDIN_DATA
);
188 translate(SSH1_SMSG_STDOUT_DATA
);
189 translate(SSH1_SMSG_STDERR_DATA
);
190 translate(SSH1_CMSG_EOF
);
191 translate(SSH1_SMSG_EXIT_STATUS
);
192 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
);
193 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE
);
194 translate(SSH1_MSG_CHANNEL_DATA
);
195 translate(SSH1_MSG_CHANNEL_CLOSE
);
196 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
);
197 translate(SSH1_SMSG_X11_OPEN
);
198 translate(SSH1_CMSG_PORT_FORWARD_REQUEST
);
199 translate(SSH1_MSG_PORT_OPEN
);
200 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING
);
201 translate(SSH1_SMSG_AGENT_OPEN
);
202 translate(SSH1_MSG_IGNORE
);
203 translate(SSH1_CMSG_EXIT_CONFIRMATION
);
204 translate(SSH1_CMSG_X11_REQUEST_FORWARDING
);
205 translate(SSH1_CMSG_AUTH_RHOSTS_RSA
);
206 translate(SSH1_MSG_DEBUG
);
207 translate(SSH1_CMSG_REQUEST_COMPRESSION
);
208 translate(SSH1_CMSG_AUTH_TIS
);
209 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE
);
210 translate(SSH1_CMSG_AUTH_TIS_RESPONSE
);
211 translate(SSH1_CMSG_AUTH_CCARD
);
212 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE
);
213 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE
);
216 static char *ssh2_pkt_type(int pkt_ctx
, int type
)
218 translate(SSH2_MSG_DISCONNECT
);
219 translate(SSH2_MSG_IGNORE
);
220 translate(SSH2_MSG_UNIMPLEMENTED
);
221 translate(SSH2_MSG_DEBUG
);
222 translate(SSH2_MSG_SERVICE_REQUEST
);
223 translate(SSH2_MSG_SERVICE_ACCEPT
);
224 translate(SSH2_MSG_KEXINIT
);
225 translate(SSH2_MSG_NEWKEYS
);
226 translatec(SSH2_MSG_KEXDH_INIT
, SSH2_PKTCTX_DHGROUP
);
227 translatec(SSH2_MSG_KEXDH_REPLY
, SSH2_PKTCTX_DHGROUP
);
228 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST
, SSH2_PKTCTX_DHGEX
);
229 translatec(SSH2_MSG_KEX_DH_GEX_GROUP
, SSH2_PKTCTX_DHGEX
);
230 translatec(SSH2_MSG_KEX_DH_GEX_INIT
, SSH2_PKTCTX_DHGEX
);
231 translatec(SSH2_MSG_KEX_DH_GEX_REPLY
, SSH2_PKTCTX_DHGEX
);
232 translate(SSH2_MSG_USERAUTH_REQUEST
);
233 translate(SSH2_MSG_USERAUTH_FAILURE
);
234 translate(SSH2_MSG_USERAUTH_SUCCESS
);
235 translate(SSH2_MSG_USERAUTH_BANNER
);
236 translatec(SSH2_MSG_USERAUTH_PK_OK
, SSH2_PKTCTX_PUBLICKEY
);
237 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
, SSH2_PKTCTX_PASSWORD
);
238 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST
, SSH2_PKTCTX_KBDINTER
);
239 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE
, SSH2_PKTCTX_KBDINTER
);
240 translate(SSH2_MSG_GLOBAL_REQUEST
);
241 translate(SSH2_MSG_REQUEST_SUCCESS
);
242 translate(SSH2_MSG_REQUEST_FAILURE
);
243 translate(SSH2_MSG_CHANNEL_OPEN
);
244 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
245 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
246 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
247 translate(SSH2_MSG_CHANNEL_DATA
);
248 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA
);
249 translate(SSH2_MSG_CHANNEL_EOF
);
250 translate(SSH2_MSG_CHANNEL_CLOSE
);
251 translate(SSH2_MSG_CHANNEL_REQUEST
);
252 translate(SSH2_MSG_CHANNEL_SUCCESS
);
253 translate(SSH2_MSG_CHANNEL_FAILURE
);
259 /* Enumeration values for fields in SSH-1 packets */
261 PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
,
262 /* These values are for communicating relevant semantics of
263 * fields to the packet logging code. */
264 PKTT_OTHER
, PKTT_PASSWORD
, PKTT_DATA
268 * Coroutine mechanics for the sillier bits of the code. If these
269 * macros look impenetrable to you, you might find it helpful to
272 * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
274 * which explains the theory behind these macros.
276 * In particular, if you are getting `case expression not constant'
277 * errors when building with MS Visual Studio, this is because MS's
278 * Edit and Continue debugging feature causes their compiler to
279 * violate ANSI C. To disable Edit and Continue debugging:
281 * - right-click ssh.c in the FileView
283 * - select the C/C++ tab and the General category
284 * - under `Debug info:', select anything _other_ than `Program
285 * Database for Edit and Continue'.
287 #define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
290 if (!ssh->t) ssh->t = snew(struct t); \
292 #define crFinish(z) } *crLine = 0; return (z); }
293 #define crFinishV } *crLine = 0; return; }
294 #define crReturn(z) \
296 *crLine =__LINE__; return (z); case __LINE__:;\
300 *crLine=__LINE__; return; case __LINE__:;\
302 #define crStop(z) do{ *crLine = 0; return (z); }while(0)
303 #define crStopV do{ *crLine = 0; return; }while(0)
304 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
305 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
307 typedef struct ssh_tag
*Ssh
;
310 static struct Packet
*ssh2_pkt_init(int pkt_type
);
311 static void ssh2_pkt_addbool(struct Packet
*, unsigned char value
);
312 static void ssh2_pkt_adduint32(struct Packet
*, unsigned long value
);
313 static void ssh2_pkt_addstring_start(struct Packet
*);
314 static void ssh2_pkt_addstring_str(struct Packet
*, char *data
);
315 static void ssh2_pkt_addstring_data(struct Packet
*, char *data
, int len
);
316 static void ssh2_pkt_addstring(struct Packet
*, char *data
);
317 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
);
318 static void ssh2_pkt_addmp(struct Packet
*, Bignum b
);
319 static int ssh2_pkt_construct(Ssh
, struct Packet
*);
320 static void ssh2_pkt_send(Ssh
, struct Packet
*);
321 static void ssh2_pkt_send_noqueue(Ssh
, struct Packet
*);
322 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
323 struct Packet
*pktin
);
324 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
325 struct Packet
*pktin
);
328 * Buffer management constants. There are several of these for
329 * various different purposes:
331 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
332 * on a local data stream before we throttle the whole SSH
333 * connection (in SSH-1 only). Throttling the whole connection is
334 * pretty drastic so we set this high in the hope it won't
337 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
338 * on the SSH connection itself before we defensively throttle
339 * _all_ local data streams. This is pretty drastic too (though
340 * thankfully unlikely in SSH-2 since the window mechanism should
341 * ensure that the server never has any need to throttle its end
342 * of the connection), so we set this high as well.
344 * - OUR_V2_WINSIZE is the maximum window size we present on SSH-2
348 #define SSH1_BUFFER_LIMIT 32768
349 #define SSH_MAX_BACKLOG 32768
350 #define OUR_V2_WINSIZE 16384
351 #define OUR_V2_MAXPKT 0x4000UL
353 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
355 static void *nullmac_make_context(void)
359 static void nullmac_free_context(void *handle
)
362 static void nullmac_key(void *handle
, unsigned char *key
)
365 static void nullmac_generate(void *handle
, unsigned char *blk
, int len
,
369 static int nullmac_verify(void *handle
, unsigned char *blk
, int len
,
374 const static struct ssh_mac ssh_mac_none
= {
375 nullmac_make_context
, nullmac_free_context
, nullmac_key
,
376 nullmac_generate
, nullmac_verify
, "none", 0
378 const static struct ssh_mac
*macs
[] = {
379 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
381 const static struct ssh_mac
*buggymacs
[] = {
382 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
385 static void *ssh_comp_none_init(void)
389 static void ssh_comp_none_cleanup(void *handle
)
392 static int ssh_comp_none_block(void *handle
, unsigned char *block
, int len
,
393 unsigned char **outblock
, int *outlen
)
397 static int ssh_comp_none_disable(void *handle
)
401 const static struct ssh_compress ssh_comp_none
= {
403 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
404 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
405 ssh_comp_none_disable
, NULL
407 extern const struct ssh_compress ssh_zlib
;
408 const static struct ssh_compress
*compressions
[] = {
409 &ssh_zlib
, &ssh_comp_none
412 enum { /* channel types */
417 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
421 * 2-3-4 tree storing channels.
424 Ssh ssh
; /* pointer back to main context */
425 unsigned remoteid
, localid
;
427 /* True if we opened this channel but server hasn't confirmed. */
430 * In SSH-1, this value contains four bits:
432 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
433 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
434 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
435 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
437 * A channel is completely finished with when all four bits are set.
441 struct ssh1_data_channel
{
444 struct ssh2_data_channel
{
446 unsigned remwindow
, remmaxpkt
;
451 struct ssh_agent_channel
{
452 unsigned char *message
;
453 unsigned char msglen
[4];
454 unsigned lensofar
, totallen
;
456 struct ssh_x11_channel
{
459 struct ssh_pfd_channel
{
466 * 2-3-4 tree storing remote->local port forwardings. SSH-1 and SSH-2
467 * use this structure in different ways, reflecting SSH-2's
468 * altogether saner approach to port forwarding.
470 * In SSH-1, you arrange a remote forwarding by sending the server
471 * the remote port number, and the local destination host:port.
472 * When a connection comes in, the server sends you back that
473 * host:port pair, and you connect to it. This is a ready-made
474 * security hole if you're not on the ball: a malicious server
475 * could send you back _any_ host:port pair, so if you trustingly
476 * connect to the address it gives you then you've just opened the
477 * entire inside of your corporate network just by connecting
478 * through it to a dodgy SSH server. Hence, we must store a list of
479 * host:port pairs we _are_ trying to forward to, and reject a
480 * connection request from the server if it's not in the list.
482 * In SSH-2, each side of the connection minds its own business and
483 * doesn't send unnecessary information to the other. You arrange a
484 * remote forwarding by sending the server just the remote port
485 * number. When a connection comes in, the server tells you which
486 * of its ports was connected to; and _you_ have to remember what
487 * local host:port pair went with that port number.
489 * Hence, in SSH-1 this structure is indexed by destination
490 * host:port pair, whereas in SSH-2 it is indexed by source port.
492 struct ssh_portfwd
; /* forward declaration */
494 struct ssh_rportfwd
{
495 unsigned sport
, dport
;
498 struct ssh_portfwd
*pfrec
;
500 #define free_rportfwd(pf) ( \
501 ((pf) ? (sfree((pf)->sportdesc)) : (void)0 ), sfree(pf) )
504 * Separately to the rportfwd tree (which is for looking up port
505 * open requests from the server), a tree of _these_ structures is
506 * used to keep track of all the currently open port forwardings,
507 * so that we can reconfigure in mid-session if the user requests
511 enum { DESTROY
, KEEP
, CREATE
} status
;
513 unsigned sport
, dport
;
516 struct ssh_rportfwd
*remote
;
520 #define free_portfwd(pf) ( \
521 ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr), \
522 sfree((pf)->sserv), sfree((pf)->dserv)) : (void)0 ), sfree(pf) )
526 long forcepad
; /* Force padding to at least this length */
528 unsigned long sequence
;
533 long encrypted_len
; /* for SSH-2 total-size counting */
536 * State associated with packet logging
540 struct logblank_t
*blanks
;
543 static void ssh1_protocol(Ssh ssh
, void *vin
, int inlen
,
544 struct Packet
*pktin
);
545 static void ssh2_protocol(Ssh ssh
, void *vin
, int inlen
,
546 struct Packet
*pktin
);
547 static void ssh1_protocol_setup(Ssh ssh
);
548 static void ssh2_protocol_setup(Ssh ssh
);
549 static void ssh_size(void *handle
, int width
, int height
);
550 static void ssh_special(void *handle
, Telnet_Special
);
551 static int ssh2_try_send(struct ssh_channel
*c
);
552 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
553 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
554 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
555 static int ssh_sendbuffer(void *handle
);
556 static int ssh_do_close(Ssh ssh
, int notify_exit
);
557 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
);
558 static int ssh2_pkt_getbool(struct Packet
*pkt
);
559 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
);
560 static void ssh2_timer(void *ctx
, long now
);
561 static int do_ssh2_transport(Ssh ssh
, void *vin
, int inlen
,
562 struct Packet
*pktin
);
564 struct rdpkt1_state_tag
{
565 long len
, pad
, biglen
, to_read
;
566 unsigned long realcrc
, gotcrc
;
570 struct Packet
*pktin
;
573 struct rdpkt2_state_tag
{
574 long len
, pad
, payload
, packetlen
, maclen
;
577 unsigned long incoming_sequence
;
578 struct Packet
*pktin
;
581 typedef void (*handler_fn_t
)(Ssh ssh
, struct Packet
*pktin
);
582 typedef void (*chandler_fn_t
)(Ssh ssh
, struct Packet
*pktin
, void *ctx
);
584 struct queued_handler
;
585 struct queued_handler
{
587 chandler_fn_t handler
;
589 struct queued_handler
*next
;
593 const struct plug_function_table
*fn
;
594 /* the above field _must_ be first in the structure */
596 SHA_State exhash
, exhashbase
;
603 unsigned char session_key
[32];
605 int v1_remote_protoflags
;
606 int v1_local_protoflags
;
607 int agentfwd_enabled
;
610 const struct ssh_cipher
*cipher
;
613 const struct ssh2_cipher
*cscipher
, *sccipher
;
614 void *cs_cipher_ctx
, *sc_cipher_ctx
;
615 const struct ssh_mac
*csmac
, *scmac
;
616 void *cs_mac_ctx
, *sc_mac_ctx
;
617 const struct ssh_compress
*cscomp
, *sccomp
;
618 void *cs_comp_ctx
, *sc_comp_ctx
;
619 const struct ssh_kex
*kex
;
620 const struct ssh_signkey
*hostkey
;
621 unsigned char v2_session_id
[20];
627 int echoing
, editing
;
631 int ospeed
, ispeed
; /* temporaries */
632 int term_width
, term_height
;
634 tree234
*channels
; /* indexed by local id */
635 struct ssh_channel
*mainchan
; /* primary session channel */
639 tree234
*rportfwds
, *portfwds
;
643 SSH_STATE_BEFORE_SIZE
,
649 int size_needed
, eof_needed
;
651 struct Packet
**queue
;
652 int queuelen
, queuesize
;
654 unsigned char *deferred_send_data
;
655 int deferred_len
, deferred_size
;
658 * Gross hack: pscp will try to start SFTP but fall back to
659 * scp1 if that fails. This variable is the means by which
660 * scp.c can reach into the SSH code and find out which one it
666 * Used for username and password input.
668 char *userpass_input_buffer
;
669 int userpass_input_buflen
;
670 int userpass_input_bufpos
;
671 int userpass_input_echo
;
678 int v1_throttle_count
;
681 int v1_stdout_throttling
;
682 unsigned long v2_outgoing_sequence
;
684 int ssh1_rdpkt_crstate
;
685 int ssh2_rdpkt_crstate
;
686 int do_ssh_init_crstate
;
687 int ssh_gotdata_crstate
;
688 int do_ssh1_login_crstate
;
689 int do_ssh1_connection_crstate
;
690 int do_ssh2_transport_crstate
;
691 int do_ssh2_authconn_crstate
;
693 void *do_ssh_init_state
;
694 void *do_ssh1_login_state
;
695 void *do_ssh2_transport_state
;
696 void *do_ssh2_authconn_state
;
698 struct rdpkt1_state_tag rdpkt1_state
;
699 struct rdpkt2_state_tag rdpkt2_state
;
701 /* SSH-1 and SSH-2 use this for different things, but both use it */
702 int protocol_initial_phase_done
;
704 void (*protocol
) (Ssh ssh
, void *vin
, int inlen
,
706 struct Packet
*(*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
709 * We maintain a full _copy_ of a Config structure here, not
710 * merely a pointer to it. That way, when we're passed a new
711 * one for reconfiguration, we can check the differences and
712 * potentially reconfigure port forwardings etc in mid-session.
717 * Used to transfer data back from async callbacks.
719 void *agent_response
;
720 int agent_response_len
;
724 * The SSH connection can be set as `frozen', meaning we are
725 * not currently accepting incoming data from the network. This
726 * is slightly more serious than setting the _socket_ as
727 * frozen, because we may already have had data passed to us
728 * from the network which we need to delay processing until
729 * after the freeze is lifted, so we also need a bufchain to
733 bufchain queued_incoming_data
;
736 * Dispatch table for packet types that we may have to deal
739 handler_fn_t packet_dispatch
[256];
742 * Queues of one-off handler functions for success/failure
743 * indications from a request.
745 struct queued_handler
*qhead
, *qtail
;
748 * This module deals with sending keepalives.
753 * Track incoming and outgoing data sizes and time, for
756 unsigned long incoming_data_size
, outgoing_data_size
, deferred_data_size
;
757 unsigned long max_data_size
;
759 long next_rekey
, last_rekey
;
760 char *deferred_rekey_reason
; /* points to STATIC string; don't free */
763 #define logevent(s) logevent(ssh->frontend, s)
765 /* logevent, only printf-formatted. */
766 static void logeventf(Ssh ssh
, const char *fmt
, ...)
772 buf
= dupvprintf(fmt
, ap
);
778 #define bombout(msg) \
780 char *text = dupprintf msg; \
781 ssh_do_close(ssh, FALSE); \
783 connection_fatal(ssh->frontend, "%s", text); \
787 /* Functions to leave bits out of the SSH packet log file. */
789 static void dont_log_password(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
791 if (ssh
->cfg
.logomitpass
)
792 pkt
->logmode
= blanktype
;
795 static void dont_log_data(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
797 if (ssh
->cfg
.logomitdata
)
798 pkt
->logmode
= blanktype
;
801 static void end_log_omission(Ssh ssh
, struct Packet
*pkt
)
803 pkt
->logmode
= PKTLOG_EMIT
;
806 static int ssh_channelcmp(void *av
, void *bv
)
808 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
809 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
810 if (a
->localid
< b
->localid
)
812 if (a
->localid
> b
->localid
)
816 static int ssh_channelfind(void *av
, void *bv
)
818 unsigned *a
= (unsigned *) av
;
819 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
827 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
829 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
830 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
832 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
833 return i
< 0 ?
-1 : +1;
834 if (a
->dport
> b
->dport
)
836 if (a
->dport
< b
->dport
)
841 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
843 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
844 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
846 if (a
->sport
> b
->sport
)
848 if (a
->sport
< b
->sport
)
854 * Special form of strcmp which can cope with NULL inputs. NULL is
855 * defined to sort before even the empty string.
857 static int nullstrcmp(const char *a
, const char *b
)
859 if (a
== NULL
&& b
== NULL
)
868 static int ssh_portcmp(void *av
, void *bv
)
870 struct ssh_portfwd
*a
= (struct ssh_portfwd
*) av
;
871 struct ssh_portfwd
*b
= (struct ssh_portfwd
*) bv
;
873 if (a
->type
> b
->type
)
875 if (a
->type
< b
->type
)
877 if (a
->addressfamily
> b
->addressfamily
)
879 if (a
->addressfamily
< b
->addressfamily
)
881 if ( (i
= nullstrcmp(a
->saddr
, b
->saddr
)) != 0)
882 return i
< 0 ?
-1 : +1;
883 if (a
->sport
> b
->sport
)
885 if (a
->sport
< b
->sport
)
887 if (a
->type
!= 'D') {
888 if ( (i
= nullstrcmp(a
->daddr
, b
->daddr
)) != 0)
889 return i
< 0 ?
-1 : +1;
890 if (a
->dport
> b
->dport
)
892 if (a
->dport
< b
->dport
)
898 static int alloc_channel_id(Ssh ssh
)
900 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
901 unsigned low
, high
, mid
;
903 struct ssh_channel
*c
;
906 * First-fit allocation of channel numbers: always pick the
907 * lowest unused one. To do this, binary-search using the
908 * counted B-tree to find the largest channel ID which is in a
909 * contiguous sequence from the beginning. (Precisely
910 * everything in that sequence must have ID equal to its tree
911 * index plus CHANNEL_NUMBER_OFFSET.)
913 tsize
= count234(ssh
->channels
);
917 while (high
- low
> 1) {
918 mid
= (high
+ low
) / 2;
919 c
= index234(ssh
->channels
, mid
);
920 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
921 low
= mid
; /* this one is fine */
923 high
= mid
; /* this one is past it */
926 * Now low points to either -1, or the tree index of the
927 * largest ID in the initial sequence.
930 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
931 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
933 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
936 static void c_write(Ssh ssh
, const char *buf
, int len
)
938 if ((flags
& FLAG_STDERR
)) {
940 for (i
= 0; i
< len
; i
++)
942 fputc(buf
[i
], stderr
);
945 from_backend(ssh
->frontend
, 1, buf
, len
);
948 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
951 for (i
= 0; i
< len
; i
++) {
953 c_write(ssh
, "\r\n", 2);
954 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
955 c_write(ssh
, buf
+ i
, 1);
959 static void c_write_str(Ssh ssh
, const char *buf
)
961 c_write(ssh
, buf
, strlen(buf
));
964 static void ssh_free_packet(struct Packet
*pkt
)
969 static struct Packet
*ssh_new_packet(void)
971 struct Packet
*pkt
= snew(struct Packet
);
975 pkt
->logmode
= PKTLOG_EMIT
;
983 * Collect incoming data in the incoming packet buffer.
984 * Decipher and verify the packet when it is completely read.
985 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
986 * Update the *data and *datalen variables.
987 * Return a Packet structure when a packet is completed.
989 static struct Packet
*ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
991 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
993 crBegin(ssh
->ssh1_rdpkt_crstate
);
995 st
->pktin
= ssh_new_packet();
998 st
->pktin
->length
= 0;
1000 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
1001 while ((*datalen
) == 0)
1003 st
->len
= (st
->len
<< 8) + **data
;
1004 (*data
)++, (*datalen
)--;
1007 st
->pad
= 8 - (st
->len
% 8);
1008 st
->biglen
= st
->len
+ st
->pad
;
1009 st
->pktin
->length
= st
->len
- 5;
1011 if (st
->biglen
< 0) {
1012 bombout(("Extremely large packet length from server suggests"
1013 " data stream corruption"));
1014 ssh_free_packet(st
->pktin
);
1018 st
->pktin
->maxlen
= st
->biglen
;
1019 st
->pktin
->data
= snewn(st
->biglen
+ APIEXTRA
, unsigned char);
1021 st
->to_read
= st
->biglen
;
1022 st
->p
= st
->pktin
->data
;
1023 while (st
->to_read
> 0) {
1024 st
->chunk
= st
->to_read
;
1025 while ((*datalen
) == 0)
1027 if (st
->chunk
> (*datalen
))
1028 st
->chunk
= (*datalen
);
1029 memcpy(st
->p
, *data
, st
->chunk
);
1031 *datalen
-= st
->chunk
;
1033 st
->to_read
-= st
->chunk
;
1036 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, st
->pktin
->data
,
1037 st
->biglen
, NULL
)) {
1038 bombout(("Network attack (CRC compensation) detected!"));
1039 ssh_free_packet(st
->pktin
);
1044 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, st
->pktin
->data
, st
->biglen
);
1046 st
->realcrc
= crc32_compute(st
->pktin
->data
, st
->biglen
- 4);
1047 st
->gotcrc
= GET_32BIT(st
->pktin
->data
+ st
->biglen
- 4);
1048 if (st
->gotcrc
!= st
->realcrc
) {
1049 bombout(("Incorrect CRC received on packet"));
1050 ssh_free_packet(st
->pktin
);
1054 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1055 st
->pktin
->savedpos
= 0;
1057 if (ssh
->v1_compressing
) {
1058 unsigned char *decompblk
;
1060 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
1061 st
->pktin
->body
- 1, st
->pktin
->length
+ 1,
1062 &decompblk
, &decomplen
)) {
1063 bombout(("Zlib decompression encountered invalid data"));
1064 ssh_free_packet(st
->pktin
);
1068 if (st
->pktin
->maxlen
< st
->pad
+ decomplen
) {
1069 st
->pktin
->maxlen
= st
->pad
+ decomplen
;
1070 st
->pktin
->data
= sresize(st
->pktin
->data
,
1071 st
->pktin
->maxlen
+ APIEXTRA
,
1073 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1076 memcpy(st
->pktin
->body
- 1, decompblk
, decomplen
);
1078 st
->pktin
->length
= decomplen
- 1;
1081 st
->pktin
->type
= st
->pktin
->body
[-1];
1084 * Log incoming packet, possibly omitting sensitive fields.
1088 struct logblank_t blank
;
1089 if (ssh
->cfg
.logomitdata
) {
1090 int do_blank
= FALSE
, blank_prefix
= 0;
1091 /* "Session data" packets - omit the data field */
1092 if ((st
->pktin
->type
== SSH1_SMSG_STDOUT_DATA
) ||
1093 (st
->pktin
->type
== SSH1_SMSG_STDERR_DATA
)) {
1094 do_blank
= TRUE
; blank_prefix
= 0;
1095 } else if (st
->pktin
->type
== SSH1_MSG_CHANNEL_DATA
) {
1096 do_blank
= TRUE
; blank_prefix
= 4;
1099 blank
.offset
= blank_prefix
;
1100 blank
.len
= st
->pktin
->length
;
1101 blank
.type
= PKTLOG_OMIT
;
1105 log_packet(ssh
->logctx
,
1106 PKT_INCOMING
, st
->pktin
->type
,
1107 ssh1_pkt_type(st
->pktin
->type
),
1108 st
->pktin
->body
, st
->pktin
->length
,
1112 crFinish(st
->pktin
);
1115 static struct Packet
*ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1117 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1119 crBegin(ssh
->ssh2_rdpkt_crstate
);
1121 st
->pktin
= ssh_new_packet();
1123 st
->pktin
->type
= 0;
1124 st
->pktin
->length
= 0;
1126 st
->cipherblk
= ssh
->sccipher
->blksize
;
1129 if (st
->cipherblk
< 8)
1132 st
->pktin
->data
= snewn(st
->cipherblk
+ APIEXTRA
, unsigned char);
1135 * Acquire and decrypt the first block of the packet. This will
1136 * contain the length and padding details.
1138 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1139 while ((*datalen
) == 0)
1141 st
->pktin
->data
[st
->i
] = *(*data
)++;
1146 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1147 st
->pktin
->data
, st
->cipherblk
);
1150 * Now get the length and padding figures.
1152 st
->len
= GET_32BIT(st
->pktin
->data
);
1153 st
->pad
= st
->pktin
->data
[4];
1156 * _Completely_ silly lengths should be stomped on before they
1157 * do us any more damage.
1159 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
1160 bombout(("Incoming packet was garbled on decryption"));
1161 ssh_free_packet(st
->pktin
);
1166 * This enables us to deduce the payload length.
1168 st
->payload
= st
->len
- st
->pad
- 1;
1170 st
->pktin
->length
= st
->payload
+ 5;
1173 * So now we can work out the total packet length.
1175 st
->packetlen
= st
->len
+ 4;
1176 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1179 * Allocate memory for the rest of the packet.
1181 st
->pktin
->maxlen
= st
->packetlen
+ st
->maclen
;
1182 st
->pktin
->data
= sresize(st
->pktin
->data
,
1183 st
->pktin
->maxlen
+ APIEXTRA
,
1187 * Read and decrypt the remainder of the packet.
1189 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1191 while ((*datalen
) == 0)
1193 st
->pktin
->data
[st
->i
] = *(*data
)++;
1196 /* Decrypt everything _except_ the MAC. */
1198 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1199 st
->pktin
->data
+ st
->cipherblk
,
1200 st
->packetlen
- st
->cipherblk
);
1202 st
->pktin
->encrypted_len
= st
->packetlen
;
1208 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, st
->pktin
->data
, st
->len
+ 4,
1209 st
->incoming_sequence
)) {
1210 bombout(("Incorrect MAC received on packet"));
1211 ssh_free_packet(st
->pktin
);
1215 st
->pktin
->sequence
= st
->incoming_sequence
++;
1218 * Decompress packet payload.
1221 unsigned char *newpayload
;
1224 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1225 st
->pktin
->data
+ 5, st
->pktin
->length
- 5,
1226 &newpayload
, &newlen
)) {
1227 if (st
->pktin
->maxlen
< newlen
+ 5) {
1228 st
->pktin
->maxlen
= newlen
+ 5;
1229 st
->pktin
->data
= sresize(st
->pktin
->data
,
1230 st
->pktin
->maxlen
+ APIEXTRA
,
1233 st
->pktin
->length
= 5 + newlen
;
1234 memcpy(st
->pktin
->data
+ 5, newpayload
, newlen
);
1239 st
->pktin
->savedpos
= 6;
1240 st
->pktin
->body
= st
->pktin
->data
;
1241 st
->pktin
->type
= st
->pktin
->data
[5];
1244 * Log incoming packet, possibly omitting sensitive fields.
1248 struct logblank_t blank
;
1249 if (ssh
->cfg
.logomitdata
) {
1250 int do_blank
= FALSE
, blank_prefix
= 0;
1251 /* "Session data" packets - omit the data field */
1252 if (st
->pktin
->type
== SSH2_MSG_CHANNEL_DATA
) {
1253 do_blank
= TRUE
; blank_prefix
= 4;
1254 } else if (st
->pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1255 do_blank
= TRUE
; blank_prefix
= 8;
1258 blank
.offset
= blank_prefix
;
1259 blank
.len
= (st
->pktin
->length
-6) - blank_prefix
;
1260 blank
.type
= PKTLOG_OMIT
;
1264 log_packet(ssh
->logctx
, PKT_INCOMING
, st
->pktin
->type
,
1265 ssh2_pkt_type(ssh
->pkt_ctx
, st
->pktin
->type
),
1266 st
->pktin
->data
+6, st
->pktin
->length
-6,
1270 crFinish(st
->pktin
);
1273 static void ssh1_pktout_size(struct Packet
*pkt
, int len
)
1277 len
+= 5; /* type and CRC */
1278 pad
= 8 - (len
% 8);
1281 pkt
->length
= len
- 5;
1282 if (pkt
->maxlen
< biglen
) {
1283 pkt
->maxlen
= biglen
;
1284 pkt
->data
= sresize(pkt
->data
, biglen
+ 4 + APIEXTRA
, unsigned char);
1286 pkt
->body
= pkt
->data
+ 4 + pad
+ 1;
1289 static struct Packet
*s_wrpkt_start(int type
, int len
)
1291 struct Packet
*pkt
= ssh_new_packet();
1292 ssh1_pktout_size(pkt
, len
);
1294 /* Initialise log omission state */
1300 static int s_wrpkt_prepare(Ssh ssh
, struct Packet
*pkt
)
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 pkt
->body
[-1] = pkt
->type
;
1318 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->type
,
1319 ssh1_pkt_type(pkt
->type
),
1320 pkt
->body
, pkt
->length
,
1321 pkt
->nblanks
, pkt
->blanks
);
1322 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1325 if (ssh
->v1_compressing
) {
1326 unsigned char *compblk
;
1328 zlib_compress_block(ssh
->cs_comp_ctx
,
1329 pkt
->body
- 1, pkt
->length
+ 1,
1330 &compblk
, &complen
);
1331 ssh1_pktout_size(pkt
, complen
- 1);
1332 memcpy(pkt
->body
- 1, compblk
, complen
);
1336 len
= pkt
->length
+ 5; /* type and CRC */
1337 pad
= 8 - (len
% 8);
1340 for (i
= 0; i
< pad
; i
++)
1341 pkt
->data
[i
+ 4] = random_byte();
1342 crc
= crc32_compute(pkt
->data
+ 4, biglen
- 4);
1343 PUT_32BIT(pkt
->data
+ biglen
, crc
);
1344 PUT_32BIT(pkt
->data
, len
);
1347 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, pkt
->data
+ 4, biglen
);
1352 static void s_wrpkt(Ssh ssh
, struct Packet
*pkt
)
1355 len
= s_wrpkt_prepare(ssh
, pkt
);
1356 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1357 if (backlog
> SSH_MAX_BACKLOG
)
1358 ssh_throttle_all(ssh
, 1, backlog
);
1361 static void s_wrpkt_defer(Ssh ssh
, struct Packet
*pkt
)
1364 len
= s_wrpkt_prepare(ssh
, pkt
);
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
, pkt
->data
, len
);
1372 ssh
->deferred_len
+= len
;
1376 * Construct a packet with the specified contents.
1378 static struct Packet
*construct_packet(Ssh ssh
, int pkttype
,
1379 va_list ap1
, va_list ap2
)
1381 unsigned char *p
, *argp
, argchar
;
1382 unsigned long argint
;
1383 int pktlen
, argtype
, arglen
;
1388 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1391 (void) va_arg(ap1
, int);
1395 (void) va_arg(ap1
, int);
1399 (void) va_arg(ap1
, unsigned char *);
1400 arglen
= va_arg(ap1
, int);
1404 argp
= va_arg(ap1
, unsigned char *);
1405 arglen
= strlen((char *)argp
);
1406 pktlen
+= 4 + arglen
;
1409 bn
= va_arg(ap1
, Bignum
);
1410 pktlen
+= ssh1_bignum_length(bn
);
1415 /* ignore this pass */
1422 pkt
= s_wrpkt_start(pkttype
, pktlen
);
1425 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1426 int offset
= p
- pkt
->body
, len
= 0;
1428 /* Actual fields in the packet */
1430 argint
= va_arg(ap2
, int);
1431 PUT_32BIT(p
, argint
);
1435 argchar
= (unsigned char) va_arg(ap2
, int);
1440 argp
= va_arg(ap2
, unsigned char *);
1441 arglen
= va_arg(ap2
, int);
1442 memcpy(p
, argp
, arglen
);
1446 argp
= va_arg(ap2
, unsigned char *);
1447 arglen
= strlen((char *)argp
);
1448 PUT_32BIT(p
, arglen
);
1449 memcpy(p
+ 4, argp
, arglen
);
1453 bn
= va_arg(ap2
, Bignum
);
1454 len
= ssh1_write_bignum(p
, bn
);
1456 /* Tokens for modifications to packet logging */
1458 dont_log_password(ssh
, pkt
, PKTLOG_BLANK
);
1461 dont_log_data(ssh
, pkt
, PKTLOG_OMIT
);
1464 end_log_omission(ssh
, pkt
);
1468 /* Deal with logfile omission, if required. */
1469 if (len
&& (pkt
->logmode
!= PKTLOG_EMIT
)) {
1471 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
,
1473 pkt
->blanks
[pkt
->nblanks
-1].offset
= offset
;
1474 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1475 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1482 static void send_packet(Ssh ssh
, int pkttype
, ...)
1486 va_start(ap1
, pkttype
);
1487 va_start(ap2
, pkttype
);
1488 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1492 ssh_free_packet(pkt
);
1495 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1499 va_start(ap1
, pkttype
);
1500 va_start(ap2
, pkttype
);
1501 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1504 s_wrpkt_defer(ssh
, pkt
);
1505 ssh_free_packet(pkt
);
1508 static int ssh_versioncmp(char *a
, char *b
)
1511 unsigned long av
, bv
;
1513 av
= strtoul(a
, &ae
, 10);
1514 bv
= strtoul(b
, &be
, 10);
1516 return (av
< bv ?
-1 : +1);
1521 av
= strtoul(ae
, &ae
, 10);
1522 bv
= strtoul(be
, &be
, 10);
1524 return (av
< bv ?
-1 : +1);
1529 * Utility routines for putting an SSH-protocol `string' and
1530 * `uint32' into a SHA state.
1533 static void sha_string(SHA_State
* s
, void *str
, int len
)
1535 unsigned char lenblk
[4];
1536 PUT_32BIT(lenblk
, len
);
1537 SHA_Bytes(s
, lenblk
, 4);
1538 SHA_Bytes(s
, str
, len
);
1541 static void sha_uint32(SHA_State
* s
, unsigned i
)
1543 unsigned char intblk
[4];
1544 PUT_32BIT(intblk
, i
);
1545 SHA_Bytes(s
, intblk
, 4);
1549 * SSH-2 packet construction functions.
1551 static void ssh2_pkt_ensure(struct Packet
*pkt
, int length
)
1553 if (pkt
->maxlen
< length
) {
1554 pkt
->maxlen
= length
+ 256;
1555 pkt
->data
= sresize(pkt
->data
, pkt
->maxlen
+ APIEXTRA
, unsigned char);
1558 static void ssh2_pkt_adddata(struct Packet
*pkt
, void *data
, int len
)
1560 if (pkt
->logmode
!= PKTLOG_EMIT
) {
1562 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
, struct logblank_t
);
1563 pkt
->blanks
[pkt
->nblanks
-1].offset
= pkt
->length
- 6;
1564 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1565 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1568 ssh2_pkt_ensure(pkt
, pkt
->length
);
1569 memcpy(pkt
->data
+ pkt
->length
- len
, data
, len
);
1571 static void ssh2_pkt_addbyte(struct Packet
*pkt
, unsigned char byte
)
1573 ssh2_pkt_adddata(pkt
, &byte
, 1);
1575 static struct Packet
*ssh2_pkt_init(int pkt_type
)
1577 struct Packet
*pkt
= ssh_new_packet();
1580 ssh2_pkt_addbyte(pkt
, (unsigned char) pkt_type
);
1583 static void ssh2_pkt_addbool(struct Packet
*pkt
, unsigned char value
)
1585 ssh2_pkt_adddata(pkt
, &value
, 1);
1587 static void ssh2_pkt_adduint32(struct Packet
*pkt
, unsigned long value
)
1590 PUT_32BIT(x
, value
);
1591 ssh2_pkt_adddata(pkt
, x
, 4);
1593 static void ssh2_pkt_addstring_start(struct Packet
*pkt
)
1595 ssh2_pkt_adduint32(pkt
, 0);
1596 pkt
->savedpos
= pkt
->length
;
1598 static void ssh2_pkt_addstring_str(struct Packet
*pkt
, char *data
)
1600 ssh2_pkt_adddata(pkt
, data
, strlen(data
));
1601 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1603 static void ssh2_pkt_addstring_data(struct Packet
*pkt
, char *data
, int len
)
1605 ssh2_pkt_adddata(pkt
, data
, len
);
1606 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1608 static void ssh2_pkt_addstring(struct Packet
*pkt
, char *data
)
1610 ssh2_pkt_addstring_start(pkt
);
1611 ssh2_pkt_addstring_str(pkt
, data
);
1613 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1616 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1617 p
= snewn(n
+ 1, unsigned char);
1619 fatalbox("out of memory");
1621 for (i
= 1; i
<= n
; i
++)
1622 p
[i
] = bignum_byte(b
, n
- i
);
1624 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1626 memmove(p
, p
+ i
, n
+ 1 - i
);
1630 static void ssh2_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1634 p
= ssh2_mpint_fmt(b
, &len
);
1635 ssh2_pkt_addstring_start(pkt
);
1636 ssh2_pkt_addstring_data(pkt
, (char *)p
, len
);
1641 * Construct an SSH-2 final-form packet: compress it, encrypt it,
1642 * put the MAC on it. Final packet, ready to be sent, is stored in
1643 * pkt->data. Total length is returned.
1645 static int ssh2_pkt_construct(Ssh ssh
, struct Packet
*pkt
)
1647 int cipherblk
, maclen
, padding
, i
;
1650 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[5],
1651 ssh2_pkt_type(ssh
->pkt_ctx
, pkt
->data
[5]),
1652 pkt
->data
+ 6, pkt
->length
- 6,
1653 pkt
->nblanks
, pkt
->blanks
);
1654 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1658 * Compress packet payload.
1661 unsigned char *newpayload
;
1664 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, pkt
->data
+ 5,
1666 &newpayload
, &newlen
)) {
1668 ssh2_pkt_adddata(pkt
, newpayload
, newlen
);
1674 * Add padding. At least four bytes, and must also bring total
1675 * length (minus MAC) up to a multiple of the block size.
1676 * If pkt->forcepad is set, make sure the packet is at least that size
1679 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1680 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1682 if (pkt
->length
+ padding
< pkt
->forcepad
)
1683 padding
= pkt
->forcepad
- pkt
->length
;
1685 (cipherblk
- (pkt
->length
+ padding
) % cipherblk
) % cipherblk
;
1686 assert(padding
<= 255);
1687 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1688 ssh2_pkt_ensure(pkt
, pkt
->length
+ padding
+ maclen
);
1689 pkt
->data
[4] = padding
;
1690 for (i
= 0; i
< padding
; i
++)
1691 pkt
->data
[pkt
->length
+ i
] = random_byte();
1692 PUT_32BIT(pkt
->data
, pkt
->length
+ padding
- 4);
1694 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, pkt
->data
,
1695 pkt
->length
+ padding
,
1696 ssh
->v2_outgoing_sequence
);
1697 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1700 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1701 pkt
->data
, pkt
->length
+ padding
);
1703 pkt
->encrypted_len
= pkt
->length
+ padding
;
1705 /* Ready-to-send packet starts at pkt->data. We return length. */
1706 return pkt
->length
+ padding
+ maclen
;
1710 * Routines called from the main SSH code to send packets. There
1711 * are quite a few of these, because we have two separate
1712 * mechanisms for delaying the sending of packets:
1714 * - In order to send an IGNORE message and a password message in
1715 * a single fixed-length blob, we require the ability to
1716 * concatenate the encrypted forms of those two packets _into_ a
1717 * single blob and then pass it to our <network.h> transport
1718 * layer in one go. Hence, there's a deferment mechanism which
1719 * works after packet encryption.
1721 * - In order to avoid sending any connection-layer messages
1722 * during repeat key exchange, we have to queue up any such
1723 * outgoing messages _before_ they are encrypted (and in
1724 * particular before they're allocated sequence numbers), and
1725 * then send them once we've finished.
1727 * I call these mechanisms `defer' and `queue' respectively, so as
1728 * to distinguish them reasonably easily.
1730 * The functions send_noqueue() and defer_noqueue() free the packet
1731 * structure they are passed. Every outgoing packet goes through
1732 * precisely one of these functions in its life; packets passed to
1733 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1734 * these or get queued, and then when the queue is later emptied
1735 * the packets are all passed to defer_noqueue().
1739 * Send an SSH-2 packet immediately, without queuing or deferring.
1741 static void ssh2_pkt_send_noqueue(Ssh ssh
, struct Packet
*pkt
)
1745 len
= ssh2_pkt_construct(ssh
, pkt
);
1746 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1747 if (backlog
> SSH_MAX_BACKLOG
)
1748 ssh_throttle_all(ssh
, 1, backlog
);
1750 ssh
->outgoing_data_size
+= pkt
->encrypted_len
;
1751 if (!ssh
->kex_in_progress
&&
1752 ssh
->max_data_size
!= 0 &&
1753 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1754 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1756 ssh_free_packet(pkt
);
1760 * Defer an SSH-2 packet.
1762 static void ssh2_pkt_defer_noqueue(Ssh ssh
, struct Packet
*pkt
)
1764 int len
= ssh2_pkt_construct(ssh
, pkt
);
1765 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1766 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1767 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1771 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1772 ssh
->deferred_len
+= len
;
1773 ssh
->deferred_data_size
+= pkt
->encrypted_len
;
1774 ssh_free_packet(pkt
);
1778 * Queue an SSH-2 packet.
1780 static void ssh2_pkt_queue(Ssh ssh
, struct Packet
*pkt
)
1782 assert(ssh
->queueing
);
1784 if (ssh
->queuelen
>= ssh
->queuesize
) {
1785 ssh
->queuesize
= ssh
->queuelen
+ 32;
1786 ssh
->queue
= sresize(ssh
->queue
, ssh
->queuesize
, struct Packet
*);
1789 ssh
->queue
[ssh
->queuelen
++] = pkt
;
1793 * Either queue or send a packet, depending on whether queueing is
1796 static void ssh2_pkt_send(Ssh ssh
, struct Packet
*pkt
)
1799 ssh2_pkt_queue(ssh
, pkt
);
1801 ssh2_pkt_send_noqueue(ssh
, pkt
);
1806 * Either queue or defer a packet, depending on whether queueing is
1809 static void ssh2_pkt_defer(Ssh ssh
, struct Packet
*pkt
)
1812 ssh2_pkt_queue(ssh
, pkt
);
1814 ssh2_pkt_defer_noqueue(ssh
, pkt
);
1819 * Send the whole deferred data block constructed by
1820 * ssh2_pkt_defer() or SSH-1's defer_packet().
1822 * The expected use of the defer mechanism is that you call
1823 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1824 * not currently queueing, this simply sets up deferred_send_data
1825 * and then sends it. If we _are_ currently queueing, the calls to
1826 * ssh2_pkt_defer() put the deferred packets on to the queue
1827 * instead, and therefore ssh_pkt_defersend() has no deferred data
1828 * to send. Hence, there's no need to make it conditional on
1831 static void ssh_pkt_defersend(Ssh ssh
)
1834 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1836 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1837 sfree(ssh
->deferred_send_data
);
1838 ssh
->deferred_send_data
= NULL
;
1839 if (backlog
> SSH_MAX_BACKLOG
)
1840 ssh_throttle_all(ssh
, 1, backlog
);
1842 ssh
->outgoing_data_size
+= ssh
->deferred_data_size
;
1843 if (!ssh
->kex_in_progress
&&
1844 ssh
->max_data_size
!= 0 &&
1845 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1846 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1847 ssh
->deferred_data_size
= 0;
1851 * Send all queued SSH-2 packets. We send them by means of
1852 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1853 * packets that needed to be lumped together.
1855 static void ssh2_pkt_queuesend(Ssh ssh
)
1859 assert(!ssh
->queueing
);
1861 for (i
= 0; i
< ssh
->queuelen
; i
++)
1862 ssh2_pkt_defer_noqueue(ssh
, ssh
->queue
[i
]);
1865 ssh_pkt_defersend(ssh
);
1869 void bndebug(char *string
, Bignum b
)
1873 p
= ssh2_mpint_fmt(b
, &len
);
1874 debug(("%s", string
));
1875 for (i
= 0; i
< len
; i
++)
1876 debug((" %02x", p
[i
]));
1882 static void sha_mpint(SHA_State
* s
, Bignum b
)
1886 p
= ssh2_mpint_fmt(b
, &len
);
1887 sha_string(s
, p
, len
);
1892 * Packet decode functions for both SSH-1 and SSH-2.
1894 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
)
1896 unsigned long value
;
1897 if (pkt
->length
- pkt
->savedpos
< 4)
1898 return 0; /* arrgh, no way to decline (FIXME?) */
1899 value
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1903 static int ssh2_pkt_getbool(struct Packet
*pkt
)
1905 unsigned long value
;
1906 if (pkt
->length
- pkt
->savedpos
< 1)
1907 return 0; /* arrgh, no way to decline (FIXME?) */
1908 value
= pkt
->body
[pkt
->savedpos
] != 0;
1912 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
)
1917 if (pkt
->length
- pkt
->savedpos
< 4)
1919 len
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1924 if (pkt
->length
- pkt
->savedpos
< *length
)
1926 *p
= (char *)(pkt
->body
+ pkt
->savedpos
);
1927 pkt
->savedpos
+= *length
;
1929 static void *ssh_pkt_getdata(struct Packet
*pkt
, int length
)
1931 if (pkt
->length
- pkt
->savedpos
< length
)
1933 pkt
->savedpos
+= length
;
1934 return pkt
->body
+ (pkt
->savedpos
- length
);
1936 static int ssh1_pkt_getrsakey(struct Packet
*pkt
, struct RSAKey
*key
,
1937 unsigned char **keystr
)
1941 j
= makekey(pkt
->body
+ pkt
->savedpos
,
1942 pkt
->length
- pkt
->savedpos
,
1949 assert(pkt
->savedpos
< pkt
->length
);
1953 static Bignum
ssh1_pkt_getmp(struct Packet
*pkt
)
1958 j
= ssh1_read_bignum(pkt
->body
+ pkt
->savedpos
,
1959 pkt
->length
- pkt
->savedpos
, &b
);
1967 static Bignum
ssh2_pkt_getmp(struct Packet
*pkt
)
1973 ssh_pkt_getstring(pkt
, &p
, &length
);
1978 b
= bignum_from_bytes((unsigned char *)p
, length
);
1983 * Helper function to add an SSH-2 signature blob to a packet.
1984 * Expects to be shown the public key blob as well as the signature
1985 * blob. Normally works just like ssh2_pkt_addstring, but will
1986 * fiddle with the signature packet if necessary for
1987 * BUG_SSH2_RSA_PADDING.
1989 static void ssh2_add_sigblob(Ssh ssh
, struct Packet
*pkt
,
1990 void *pkblob_v
, int pkblob_len
,
1991 void *sigblob_v
, int sigblob_len
)
1993 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1994 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1996 /* dmemdump(pkblob, pkblob_len); */
1997 /* dmemdump(sigblob, sigblob_len); */
2000 * See if this is in fact an ssh-rsa signature and a buggy
2001 * server; otherwise we can just do this the easy way.
2003 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
2004 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
2005 int pos
, len
, siglen
;
2008 * Find the byte length of the modulus.
2011 pos
= 4+7; /* skip over "ssh-rsa" */
2012 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
2013 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
2014 pos
+= 4; /* find modulus itself */
2015 while (len
> 0 && pkblob
[pos
] == 0)
2017 /* debug(("modulus length is %d\n", len)); */
2020 * Now find the signature integer.
2022 pos
= 4+7; /* skip over "ssh-rsa" */
2023 siglen
= GET_32BIT(sigblob
+pos
);
2024 /* debug(("signature length is %d\n", siglen)); */
2026 if (len
!= siglen
) {
2027 unsigned char newlen
[4];
2028 ssh2_pkt_addstring_start(pkt
);
2029 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, pos
);
2030 /* dmemdump(sigblob, pos); */
2031 pos
+= 4; /* point to start of actual sig */
2032 PUT_32BIT(newlen
, len
);
2033 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 4);
2034 /* dmemdump(newlen, 4); */
2036 while (len
-- > siglen
) {
2037 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 1);
2038 /* dmemdump(newlen, 1); */
2040 ssh2_pkt_addstring_data(pkt
, (char *)(sigblob
+pos
), siglen
);
2041 /* dmemdump(sigblob+pos, siglen); */
2045 /* Otherwise fall through and do it the easy way. */
2048 ssh2_pkt_addstring_start(pkt
);
2049 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, sigblob_len
);
2053 * Examine the remote side's version string and compare it against
2054 * a list of known buggy implementations.
2056 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
2058 char *imp
; /* pointer to implementation part */
2060 imp
+= strcspn(imp
, "-");
2062 imp
+= strcspn(imp
, "-");
2065 ssh
->remote_bugs
= 0;
2067 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
2068 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
2069 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
2070 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
2071 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
2072 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
2074 * These versions don't support SSH1_MSG_IGNORE, so we have
2075 * to use a different defence against password length
2078 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
2079 logevent("We believe remote version has SSH-1 ignore bug");
2082 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
2083 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
2084 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
2086 * These versions need a plain password sent; they can't
2087 * handle having a null and a random length of data after
2090 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
2091 logevent("We believe remote version needs a plain SSH-1 password");
2094 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
2095 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
2096 (!strcmp(imp
, "Cisco-1.25")))) {
2098 * These versions apparently have no clue whatever about
2099 * RSA authentication and will panic and die if they see
2100 * an AUTH_RSA message.
2102 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
2103 logevent("We believe remote version can't handle SSH-1 RSA authentication");
2106 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
2107 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
2108 !wc_match("* VShell", imp
) &&
2109 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
2110 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
2111 wc_match("2.1 *", imp
)))) {
2113 * These versions have the HMAC bug.
2115 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
2116 logevent("We believe remote version has SSH-2 HMAC bug");
2119 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2120 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2121 !wc_match("* VShell", imp
) &&
2122 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2124 * These versions have the key-derivation bug (failing to
2125 * include the literal shared secret in the hashes that
2126 * generate the keys).
2128 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2129 logevent("We believe remote version has SSH-2 key-derivation bug");
2132 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2133 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2134 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2135 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2137 * These versions have the SSH-2 RSA padding bug.
2139 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2140 logevent("We believe remote version has SSH-2 RSA padding bug");
2143 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2144 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2145 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2147 * These versions have the SSH-2 session-ID bug in
2148 * public-key authentication.
2150 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2151 logevent("We believe remote version has SSH-2 public-key-session-ID bug");
2154 if (ssh
->cfg
.sshbug_rekey2
== FORCE_ON
||
2155 (ssh
->cfg
.sshbug_rekey2
== AUTO
&&
2156 (wc_match("OpenSSH_2.[0-4]*", imp
) ||
2157 wc_match("OpenSSH_2.5.[0-3]*", imp
) ||
2158 wc_match("Sun_SSH_1.0", imp
) ||
2159 wc_match("Sun_SSH_1.0.1", imp
)))) {
2161 * These versions have the SSH-2 rekey bug.
2163 ssh
->remote_bugs
|= BUG_SSH2_REKEY
;
2164 logevent("We believe remote version has SSH-2 rekey bug");
2169 * The `software version' part of an SSH version string is required
2170 * to contain no spaces or minus signs.
2172 static void ssh_fix_verstring(char *str
)
2174 /* Eat "SSH-<protoversion>-". */
2175 assert(*str
== 'S'); str
++;
2176 assert(*str
== 'S'); str
++;
2177 assert(*str
== 'H'); str
++;
2178 assert(*str
== '-'); str
++;
2179 while (*str
&& *str
!= '-') str
++;
2180 assert(*str
== '-'); str
++;
2182 /* Convert minus signs and spaces in the remaining string into
2185 if (*str
== '-' || *str
== ' ')
2191 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2193 struct do_ssh_init_state
{
2201 crState(do_ssh_init_state
);
2203 crBegin(ssh
->do_ssh_init_crstate
);
2205 /* Search for the string "SSH-" in the input. */
2208 static const int transS
[] = { 1, 2, 2, 1 };
2209 static const int transH
[] = { 0, 0, 3, 0 };
2210 static const int transminus
[] = { 0, 0, 0, -1 };
2212 s
->i
= transS
[s
->i
];
2214 s
->i
= transH
[s
->i
];
2216 s
->i
= transminus
[s
->i
];
2221 crReturn(1); /* get another character */
2225 s
->vstring
= snewn(s
->vstrsize
, char);
2226 strcpy(s
->vstring
, "SSH-");
2230 crReturn(1); /* get another char */
2231 if (s
->vslen
>= s
->vstrsize
- 1) {
2233 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2235 s
->vstring
[s
->vslen
++] = c
;
2238 s
->version
[s
->i
] = '\0';
2240 } else if (s
->i
< sizeof(s
->version
) - 1)
2241 s
->version
[s
->i
++] = c
;
2242 } else if (c
== '\012')
2246 ssh
->agentfwd_enabled
= FALSE
;
2247 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2249 s
->vstring
[s
->vslen
] = 0;
2250 s
->vstring
[strcspn(s
->vstring
, "\015\012")] = '\0';/* remove EOL chars */
2251 logeventf(ssh
, "Server version: %s", s
->vstring
);
2252 ssh_detect_bugs(ssh
, s
->vstring
);
2255 * Decide which SSH protocol version to support.
2258 /* Anything strictly below "2.0" means protocol 1 is supported. */
2259 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2260 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2261 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2263 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2264 bombout(("SSH protocol version 1 required by user but not provided by server"));
2267 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2268 bombout(("SSH protocol version 2 required by user but not provided by server"));
2275 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2277 * Construct a v2 version string.
2279 verstring
= dupprintf("SSH-2.0-%s\015\012", sshver
);
2283 * Construct a v1 version string.
2285 verstring
= dupprintf("SSH-%s-%s\012",
2286 (ssh_versioncmp(s
->version
, "1.5") <= 0 ?
2287 s
->version
: "1.5"),
2292 ssh_fix_verstring(verstring
);
2294 if (ssh
->version
== 2) {
2296 * Hash our version string and their version string.
2298 SHA_Init(&ssh
->exhashbase
);
2299 sha_string(&ssh
->exhashbase
, verstring
,
2300 strcspn(verstring
, "\015\012"));
2301 sha_string(&ssh
->exhashbase
, s
->vstring
,
2302 strcspn(s
->vstring
, "\015\012"));
2305 * Initialise SSH-2 protocol.
2307 ssh
->protocol
= ssh2_protocol
;
2308 ssh2_protocol_setup(ssh
);
2309 ssh
->s_rdpkt
= ssh2_rdpkt
;
2312 * Initialise SSH-1 protocol.
2314 ssh
->protocol
= ssh1_protocol
;
2315 ssh1_protocol_setup(ssh
);
2316 ssh
->s_rdpkt
= ssh1_rdpkt
;
2318 logeventf(ssh
, "We claim version: %.*s",
2319 strcspn(verstring
, "\015\012"), verstring
);
2320 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2324 logeventf(ssh
, "Using SSH protocol version %d", ssh
->version
);
2326 update_specials_menu(ssh
->frontend
);
2327 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2328 ssh
->pinger
= pinger_new(&ssh
->cfg
, &ssh_backend
, ssh
);
2335 static void ssh_process_incoming_data(Ssh ssh
,
2336 unsigned char **data
, int *datalen
)
2338 struct Packet
*pktin
= ssh
->s_rdpkt(ssh
, data
, datalen
);
2340 ssh
->protocol(ssh
, NULL
, 0, pktin
);
2341 ssh_free_packet(pktin
);
2345 static void ssh_queue_incoming_data(Ssh ssh
,
2346 unsigned char **data
, int *datalen
)
2348 bufchain_add(&ssh
->queued_incoming_data
, *data
, *datalen
);
2353 static void ssh_process_queued_incoming_data(Ssh ssh
)
2356 unsigned char *data
;
2359 while (!ssh
->frozen
&& bufchain_size(&ssh
->queued_incoming_data
)) {
2360 bufchain_prefix(&ssh
->queued_incoming_data
, &vdata
, &len
);
2364 while (!ssh
->frozen
&& len
> 0)
2365 ssh_process_incoming_data(ssh
, &data
, &len
);
2368 bufchain_consume(&ssh
->queued_incoming_data
, origlen
- len
);
2372 static void ssh_set_frozen(Ssh ssh
, int frozen
)
2375 sk_set_frozen(ssh
->s
, frozen
);
2376 ssh
->frozen
= frozen
;
2379 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2381 crBegin(ssh
->ssh_gotdata_crstate
);
2384 * To begin with, feed the characters one by one to the
2385 * protocol initialisation / selection function do_ssh_init().
2386 * When that returns 0, we're done with the initial greeting
2387 * exchange and can move on to packet discipline.
2390 int ret
; /* need not be kept across crReturn */
2392 crReturnV
; /* more data please */
2393 ret
= do_ssh_init(ssh
, *data
);
2401 * We emerge from that loop when the initial negotiation is
2402 * over and we have selected an s_rdpkt function. Now pass
2403 * everything to s_rdpkt, and then pass the resulting packets
2404 * to the proper protocol handler.
2410 * Process queued data if there is any.
2412 ssh_process_queued_incoming_data(ssh
);
2415 while (datalen
> 0) {
2417 ssh_queue_incoming_data(ssh
, &data
, &datalen
);
2419 ssh_process_incoming_data(ssh
, &data
, &datalen
);
2421 if (ssh
->state
== SSH_STATE_CLOSED
)
2429 static int ssh_do_close(Ssh ssh
, int notify_exit
)
2432 struct ssh_channel
*c
;
2434 ssh
->state
= SSH_STATE_CLOSED
;
2435 expire_timer_context(ssh
);
2440 notify_remote_exit(ssh
->frontend
);
2445 * Now we must shut down any port- and X-forwarded channels going
2446 * through this connection.
2448 if (ssh
->channels
) {
2449 while (NULL
!= (c
= index234(ssh
->channels
, 0))) {
2452 x11_close(c
->u
.x11
.s
);
2455 pfd_close(c
->u
.pfd
.s
);
2458 del234(ssh
->channels
, c
); /* moving next one to index 0 */
2459 if (ssh
->version
== 2)
2460 bufchain_clear(&c
->v
.v2
.outbuffer
);
2465 * Go through port-forwardings, and close any associated
2466 * listening sockets.
2468 if (ssh
->portfwds
) {
2469 struct ssh_portfwd
*pf
;
2470 while (NULL
!= (pf
= index234(ssh
->portfwds
, 0))) {
2471 /* Dispose of any listening socket. */
2473 pfd_terminate(pf
->local
);
2474 del234(ssh
->portfwds
, pf
); /* moving next one to index 0 */
2482 static void ssh_log(Plug plug
, int type
, SockAddr addr
, int port
,
2483 const char *error_msg
, int error_code
)
2485 Ssh ssh
= (Ssh
) plug
;
2486 char addrbuf
[256], *msg
;
2488 sk_getaddr(addr
, addrbuf
, lenof(addrbuf
));
2491 msg
= dupprintf("Connecting to %s port %d", addrbuf
, port
);
2493 msg
= dupprintf("Failed to connect to %s: %s", addrbuf
, error_msg
);
2499 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2502 Ssh ssh
= (Ssh
) plug
;
2503 int need_notify
= ssh_do_close(ssh
, FALSE
);
2505 if (!error_msg
&& !ssh
->close_expected
) {
2506 error_msg
= "Server unexpectedly closed network connection";
2510 notify_remote_exit(ssh
->frontend
);
2513 /* A socket error has occurred. */
2514 logevent(error_msg
);
2515 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2517 logevent("Server closed network connection");
2522 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2524 Ssh ssh
= (Ssh
) plug
;
2525 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2526 if (ssh
->state
== SSH_STATE_CLOSED
) {
2527 ssh_do_close(ssh
, TRUE
);
2533 static void ssh_sent(Plug plug
, int bufsize
)
2535 Ssh ssh
= (Ssh
) plug
;
2537 * If the send backlog on the SSH socket itself clears, we
2538 * should unthrottle the whole world if it was throttled.
2540 if (bufsize
< SSH_MAX_BACKLOG
)
2541 ssh_throttle_all(ssh
, 0, bufsize
);
2545 * Connect to specified host and port.
2546 * Returns an error message, or NULL on success.
2547 * Also places the canonical host name into `realhost'. It must be
2548 * freed by the caller.
2550 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2551 char **realhost
, int nodelay
, int keepalive
)
2553 static const struct plug_function_table fn_table
= {
2564 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2565 if (!ssh
->savedhost
)
2566 fatalbox("Out of memory");
2567 strcpy(ssh
->savedhost
, host
);
2570 port
= 22; /* default ssh port */
2571 ssh
->savedport
= port
;
2576 logeventf(ssh
, "Looking up host \"%s\"%s", host
,
2577 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV4 ?
" (IPv4)" :
2578 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV6 ?
" (IPv6)" : "")));
2579 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
,
2580 ssh
->cfg
.addressfamily
);
2581 if ((err
= sk_addr_error(addr
)) != NULL
) {
2589 ssh
->fn
= &fn_table
;
2590 ssh
->s
= new_connection(addr
, *realhost
, port
,
2591 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2592 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2594 notify_remote_exit(ssh
->frontend
);
2602 * Throttle or unthrottle the SSH connection.
2604 static void ssh1_throttle(Ssh ssh
, int adjust
)
2606 int old_count
= ssh
->v1_throttle_count
;
2607 ssh
->v1_throttle_count
+= adjust
;
2608 assert(ssh
->v1_throttle_count
>= 0);
2609 if (ssh
->v1_throttle_count
&& !old_count
) {
2610 ssh_set_frozen(ssh
, 1);
2611 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2612 ssh_set_frozen(ssh
, 0);
2617 * Throttle or unthrottle _all_ local data streams (for when sends
2618 * on the SSH connection itself back up).
2620 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2623 struct ssh_channel
*c
;
2625 if (enable
== ssh
->throttled_all
)
2627 ssh
->throttled_all
= enable
;
2628 ssh
->overall_bufsize
= bufsize
;
2631 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2633 case CHAN_MAINSESSION
:
2635 * This is treated separately, outside the switch.
2639 x11_override_throttle(c
->u
.x11
.s
, enable
);
2642 /* Agent channels require no buffer management. */
2645 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2652 * Username and password input, abstracted off into routines
2653 * reusable in several places - even between SSH-1 and SSH-2.
2656 /* Set up a username or password input loop on a given buffer. */
2657 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2659 ssh
->userpass_input_buffer
= buffer
;
2660 ssh
->userpass_input_buflen
= buflen
;
2661 ssh
->userpass_input_bufpos
= 0;
2662 ssh
->userpass_input_echo
= echo
;
2666 * Process some terminal data in the course of username/password
2667 * input. Returns >0 for success (line of input returned in
2668 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2669 * for inconclusive (keep waiting for more input please).
2671 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2676 switch (c
= *in
++) {
2679 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2680 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2685 if (ssh
->userpass_input_bufpos
> 0) {
2686 if (ssh
->userpass_input_echo
)
2687 c_write_str(ssh
, "\b \b");
2688 ssh
->userpass_input_bufpos
--;
2693 while (ssh
->userpass_input_bufpos
> 0) {
2694 if (ssh
->userpass_input_echo
)
2695 c_write_str(ssh
, "\b \b");
2696 ssh
->userpass_input_bufpos
--;
2705 * This simplistic check for printability is disabled
2706 * when we're doing password input, because some people
2707 * have control characters in their passwords.o
2709 if ((!ssh
->userpass_input_echo
||
2710 (c
>= ' ' && c
<= '~') ||
2711 ((unsigned char) c
>= 160))
2712 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2713 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2714 if (ssh
->userpass_input_echo
)
2715 c_write(ssh
, &c
, 1);
2723 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2725 Ssh ssh
= (Ssh
) sshv
;
2727 ssh
->agent_response
= reply
;
2728 ssh
->agent_response_len
= replylen
;
2730 if (ssh
->version
== 1)
2731 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2733 do_ssh2_authconn(ssh
, NULL
, -1, NULL
);
2736 static void ssh_dialog_callback(void *sshv
, int ret
)
2738 Ssh ssh
= (Ssh
) sshv
;
2740 ssh
->user_response
= ret
;
2742 if (ssh
->version
== 1)
2743 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2745 do_ssh2_transport(ssh
, NULL
, -1, NULL
);
2748 * This may have unfrozen the SSH connection, so do a
2751 ssh_process_queued_incoming_data(ssh
);
2754 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2756 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2758 void *sentreply
= reply
;
2761 /* Fake SSH_AGENT_FAILURE. */
2762 sentreply
= "\0\0\0\1\5";
2765 if (ssh
->version
== 2) {
2766 ssh2_add_channel_data(c
, sentreply
, replylen
);
2769 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2770 PKT_INT
, c
->remoteid
,
2773 PKT_DATA
, sentreply
, replylen
,
2782 * Handle the key exchange and user authentication phases.
2784 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
2785 struct Packet
*pktin
)
2788 unsigned char cookie
[8], *ptr
;
2789 struct RSAKey servkey
, hostkey
;
2790 struct MD5Context md5c
;
2791 struct do_ssh1_login_state
{
2793 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2794 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2795 int tried_publickey
, tried_agent
;
2796 int tis_auth_refused
, ccard_auth_refused
;
2797 unsigned char session_id
[16];
2800 void *publickey_blob
;
2801 int publickey_bloblen
;
2807 unsigned char request
[5], *response
, *p
;
2817 crState(do_ssh1_login_state
);
2819 crBegin(ssh
->do_ssh1_login_crstate
);
2824 if (pktin
->type
!= SSH1_SMSG_PUBLIC_KEY
) {
2825 bombout(("Public key packet not received"));
2829 logevent("Received public keys");
2831 ptr
= ssh_pkt_getdata(pktin
, 8);
2833 bombout(("SSH-1 public key packet stopped before random cookie"));
2836 memcpy(cookie
, ptr
, 8);
2838 if (!ssh1_pkt_getrsakey(pktin
, &servkey
, &s
->keystr1
) ||
2839 !ssh1_pkt_getrsakey(pktin
, &hostkey
, &s
->keystr2
)) {
2840 bombout(("Failed to read SSH-1 public keys from public key packet"));
2845 * Log the host key fingerprint.
2849 logevent("Host key fingerprint is:");
2850 strcpy(logmsg
, " ");
2851 hostkey
.comment
= NULL
;
2852 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2853 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2857 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(pktin
);
2858 s
->supported_ciphers_mask
= ssh_pkt_getuint32(pktin
);
2859 s
->supported_auths_mask
= ssh_pkt_getuint32(pktin
);
2861 ssh
->v1_local_protoflags
=
2862 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2863 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2866 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2867 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2868 MD5Update(&md5c
, cookie
, 8);
2869 MD5Final(s
->session_id
, &md5c
);
2871 for (i
= 0; i
< 32; i
++)
2872 ssh
->session_key
[i
] = random_byte();
2875 * Verify that the `bits' and `bytes' parameters match.
2877 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
2878 servkey
.bits
> servkey
.bytes
* 8) {
2879 bombout(("SSH-1 public keys were badly formatted"));
2883 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2885 s
->rsabuf
= snewn(s
->len
, unsigned char);
2887 fatalbox("Out of memory");
2890 * Verify the host key.
2894 * First format the key into a string.
2896 int len
= rsastr_len(&hostkey
);
2897 char fingerprint
[100];
2898 char *keystr
= snewn(len
, char);
2900 fatalbox("Out of memory");
2901 rsastr_fmt(keystr
, &hostkey
);
2902 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2904 ssh_set_frozen(ssh
, 1);
2905 s
->dlgret
= verify_ssh_host_key(ssh
->frontend
,
2906 ssh
->savedhost
, ssh
->savedport
,
2907 "rsa", keystr
, fingerprint
,
2908 ssh_dialog_callback
, ssh
);
2910 if (s
->dlgret
< 0) {
2914 bombout(("Unexpected data from server while waiting"
2915 " for user host key response"));
2918 } while (pktin
|| inlen
> 0);
2919 s
->dlgret
= ssh
->user_response
;
2921 ssh_set_frozen(ssh
, 0);
2923 if (s
->dlgret
== 0) {
2924 ssh
->close_expected
= TRUE
;
2925 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2930 for (i
= 0; i
< 32; i
++) {
2931 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2933 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2936 if (hostkey
.bytes
> servkey
.bytes
) {
2937 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
2939 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2941 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2943 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2946 bombout(("SSH-1 public key encryptions failed due to bad formatting"));
2950 logevent("Encrypted session key");
2953 int cipher_chosen
= 0, warn
= 0;
2954 char *cipher_string
= NULL
;
2956 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2957 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
2958 if (next_cipher
== CIPHER_WARN
) {
2959 /* If/when we choose a cipher, warn about it */
2961 } else if (next_cipher
== CIPHER_AES
) {
2962 /* XXX Probably don't need to mention this. */
2963 logevent("AES not supported in SSH-1, skipping");
2965 switch (next_cipher
) {
2966 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2967 cipher_string
= "3DES"; break;
2968 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2969 cipher_string
= "Blowfish"; break;
2970 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2971 cipher_string
= "single-DES"; break;
2973 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2977 if (!cipher_chosen
) {
2978 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2979 bombout(("Server violates SSH-1 protocol by not "
2980 "supporting 3DES encryption"));
2982 /* shouldn't happen */
2983 bombout(("No supported ciphers found"));
2987 /* Warn about chosen cipher if necessary. */
2989 ssh_set_frozen(ssh
, 1);
2990 s
->dlgret
= askalg(ssh
->frontend
, "cipher", cipher_string
,
2991 ssh_dialog_callback
, ssh
);
2992 if (s
->dlgret
< 0) {
2996 bombout(("Unexpected data from server while waiting"
2997 " for user response"));
3000 } while (pktin
|| inlen
> 0);
3001 s
->dlgret
= ssh
->user_response
;
3003 ssh_set_frozen(ssh
, 0);
3004 if (s
->dlgret
== 0) {
3005 ssh
->close_expected
= TRUE
;
3006 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3012 switch (s
->cipher_type
) {
3013 case SSH_CIPHER_3DES
:
3014 logevent("Using 3DES encryption");
3016 case SSH_CIPHER_DES
:
3017 logevent("Using single-DES encryption");
3019 case SSH_CIPHER_BLOWFISH
:
3020 logevent("Using Blowfish encryption");
3024 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
3025 PKT_CHAR
, s
->cipher_type
,
3026 PKT_DATA
, cookie
, 8,
3027 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
3028 PKT_DATA
, s
->rsabuf
, s
->len
,
3029 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
3031 logevent("Trying to enable encryption...");
3035 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
3036 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
3038 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
3039 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
3040 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
3042 ssh
->crcda_ctx
= crcda_make_context();
3043 logevent("Installing CRC compensation attack detector");
3045 if (servkey
.modulus
) {
3046 sfree(servkey
.modulus
);
3047 servkey
.modulus
= NULL
;
3049 if (servkey
.exponent
) {
3050 sfree(servkey
.exponent
);
3051 servkey
.exponent
= NULL
;
3053 if (hostkey
.modulus
) {
3054 sfree(hostkey
.modulus
);
3055 hostkey
.modulus
= NULL
;
3057 if (hostkey
.exponent
) {
3058 sfree(hostkey
.exponent
);
3059 hostkey
.exponent
= NULL
;
3063 if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3064 bombout(("Encryption not successfully enabled"));
3068 logevent("Successfully started encryption");
3072 if (!*ssh
->cfg
.username
) {
3073 if (ssh_get_line
&& !ssh_getline_pw_only
) {
3074 if (!ssh_get_line("login as: ",
3075 s
->username
, sizeof(s
->username
), FALSE
)) {
3077 * get_line failed to get a username.
3080 logevent("No username provided. Abandoning session.");
3081 ssh
->close_expected
= TRUE
;
3082 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3086 int ret
; /* need not be kept over crReturn */
3087 c_write_str(ssh
, "login as: ");
3090 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
3092 crWaitUntil(!pktin
);
3093 ret
= process_userpass_input(ssh
, in
, inlen
);
3097 c_write_str(ssh
, "\r\n");
3100 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
3101 s
->username
[sizeof(s
->username
)-1] = '\0';
3104 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
3106 char userlog
[22 + sizeof(s
->username
)];
3107 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
3109 if (flags
& FLAG_INTERACTIVE
&&
3110 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
3111 strcat(userlog
, "\r\n");
3112 c_write_str(ssh
, userlog
);
3119 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
3120 /* We must not attempt PK auth. Pretend we've already tried it. */
3121 s
->tried_publickey
= s
->tried_agent
= 1;
3123 s
->tried_publickey
= s
->tried_agent
= 0;
3125 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
3126 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
3127 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
3128 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
3129 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
3130 s
->publickey_blob
= NULL
;
3132 s
->publickey_blob
= NULL
;
3134 while (pktin
->type
== SSH1_SMSG_FAILURE
) {
3135 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
3137 if (agent_exists() && !s
->tried_agent
) {
3139 * Attempt RSA authentication using Pageant.
3145 logevent("Pageant is running. Requesting keys.");
3147 /* Request the keys held by the agent. */
3148 PUT_32BIT(s
->request
, 1);
3149 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
3150 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
3151 ssh_agent_callback
, ssh
)) {
3155 bombout(("Unexpected data from server while waiting"
3156 " for agent response"));
3159 } while (pktin
|| inlen
> 0);
3160 r
= ssh
->agent_response
;
3161 s
->responselen
= ssh
->agent_response_len
;
3163 s
->response
= (unsigned char *) r
;
3164 if (s
->response
&& s
->responselen
>= 5 &&
3165 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
3166 s
->p
= s
->response
+ 5;
3167 s
->nkeys
= GET_32BIT(s
->p
);
3169 logeventf(ssh
, "Pageant has %d SSH-1 keys", s
->nkeys
);
3170 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
3171 logeventf(ssh
, "Trying Pageant key #%d", s
->keyi
);
3172 if (s
->publickey_blob
&&
3173 !memcmp(s
->p
, s
->publickey_blob
,
3174 s
->publickey_bloblen
)) {
3175 logevent("This key matches configured key file");
3176 s
->tried_publickey
= 1;
3181 do { /* do while (0) to make breaking easy */
3182 n
= ssh1_read_bignum
3183 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3188 n
= ssh1_read_bignum
3189 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3194 if (s
->responselen
- (s
->p
-s
->response
) < 4)
3196 s
->commentlen
= GET_32BIT(s
->p
);
3198 if (s
->responselen
- (s
->p
-s
->response
) <
3201 s
->commentp
= (char *)s
->p
;
3202 s
->p
+= s
->commentlen
;
3206 logevent("Pageant key list packet was truncated");
3210 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3211 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3213 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3214 logevent("Key refused");
3217 logevent("Received RSA challenge");
3218 if ((s
->challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3219 bombout(("Server's RSA challenge was badly formatted"));
3224 char *agentreq
, *q
, *ret
;
3227 len
= 1 + 4; /* message type, bit count */
3228 len
+= ssh1_bignum_length(s
->key
.exponent
);
3229 len
+= ssh1_bignum_length(s
->key
.modulus
);
3230 len
+= ssh1_bignum_length(s
->challenge
);
3231 len
+= 16; /* session id */
3232 len
+= 4; /* response format */
3233 agentreq
= snewn(4 + len
, char);
3234 PUT_32BIT(agentreq
, len
);
3236 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
3237 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
3239 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
3240 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
3241 q
+= ssh1_write_bignum(q
, s
->challenge
);
3242 memcpy(q
, s
->session_id
, 16);
3244 PUT_32BIT(q
, 1); /* response format */
3245 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
3246 ssh_agent_callback
, ssh
)) {
3251 bombout(("Unexpected data from server"
3252 " while waiting for agent"
3256 } while (pktin
|| inlen
> 0);
3257 vret
= ssh
->agent_response
;
3258 retlen
= ssh
->agent_response_len
;
3263 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
3264 logevent("Sending Pageant's response");
3265 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3266 PKT_DATA
, ret
+ 5, 16,
3270 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
3272 ("Pageant's response accepted");
3273 if (flags
& FLAG_VERBOSE
) {
3274 c_write_str(ssh
, "Authenticated using"
3276 c_write(ssh
, s
->commentp
,
3278 c_write_str(ssh
, "\" from agent\r\n");
3283 ("Pageant's response not accepted");
3286 ("Pageant failed to answer challenge");
3290 logevent("No reply received from Pageant");
3293 freebn(s
->key
.exponent
);
3294 freebn(s
->key
.modulus
);
3295 freebn(s
->challenge
);
3304 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
3305 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
3307 if (ssh
->cfg
.try_tis_auth
&&
3308 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3309 !s
->tis_auth_refused
) {
3310 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3311 logevent("Requested TIS authentication");
3312 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3314 if (pktin
->type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3315 logevent("TIS authentication declined");
3316 if (flags
& FLAG_INTERACTIVE
)
3317 c_write_str(ssh
, "TIS authentication refused.\r\n");
3318 s
->tis_auth_refused
= 1;
3324 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3326 bombout(("TIS challenge packet was badly formed"));
3329 c_write_str(ssh
, "Using TIS authentication.\r\n");
3330 logevent("Received TIS challenge");
3331 if (challengelen
> sizeof(s
->prompt
) - 1)
3332 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3333 memcpy(s
->prompt
, challenge
, challengelen
);
3334 /* Prompt heuristic comes from OpenSSH */
3335 strncpy(s
->prompt
+ challengelen
,
3336 memchr(s
->prompt
, '\n', challengelen
) ?
3337 "": "\r\nResponse: ",
3338 (sizeof s
->prompt
) - challengelen
);
3339 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
3342 if (ssh
->cfg
.try_tis_auth
&&
3343 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3344 !s
->ccard_auth_refused
) {
3345 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3346 logevent("Requested CryptoCard authentication");
3347 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3349 if (pktin
->type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3350 logevent("CryptoCard authentication declined");
3351 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3352 s
->ccard_auth_refused
= 1;
3358 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3360 bombout(("CryptoCard challenge packet was badly formed"));
3363 c_write_str(ssh
, "Using CryptoCard authentication.\r\n");
3364 logevent("Received CryptoCard challenge");
3365 if (challengelen
> sizeof(s
->prompt
) - 1)
3366 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3367 memcpy(s
->prompt
, challenge
, challengelen
);
3368 strncpy(s
->prompt
+ challengelen
,
3369 memchr(s
->prompt
, '\n', challengelen
) ?
3370 "" : "\r\nResponse: ",
3371 sizeof(s
->prompt
) - challengelen
);
3372 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
3375 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3376 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
3377 s
->username
, ssh
->savedhost
);
3379 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3380 char *comment
= NULL
;
3382 if (flags
& FLAG_VERBOSE
)
3383 c_write_str(ssh
, "Trying public key authentication.\r\n");
3384 logeventf(ssh
, "Trying public key \"%s\"",
3385 filename_to_str(&ssh
->cfg
.keyfile
));
3386 type
= key_type(&ssh
->cfg
.keyfile
);
3387 if (type
!= SSH_KEYTYPE_SSH1
) {
3388 char *msg
= dupprintf("Key is of wrong type (%s)",
3389 key_type_to_str(type
));
3391 c_write_str(ssh
, msg
);
3392 c_write_str(ssh
, "\r\n");
3394 s
->tried_publickey
= 1;
3397 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
3398 if (flags
& FLAG_VERBOSE
)
3399 c_write_str(ssh
, "No passphrase required.\r\n");
3402 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
3407 * Show password prompt, having first obtained it via a TIS
3408 * or CryptoCard exchange if we're doing TIS or CryptoCard
3412 if (!ssh_get_line(s
->prompt
, s
->password
,
3413 sizeof(s
->password
), TRUE
)) {
3415 * get_line failed to get a password (for example
3416 * because one was supplied on the command line
3417 * which has already failed to work). Terminate.
3419 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
3420 PKT_STR
, "No more passwords available to try",
3422 logevent("Unable to authenticate");
3423 connection_fatal(ssh
->frontend
, "Unable to authenticate");
3424 ssh
->close_expected
= TRUE
;
3425 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3429 /* Prompt may have come from server. We've munged it a bit, so
3430 * we know it to be zero-terminated at least once. */
3431 int ret
; /* need not be saved over crReturn */
3432 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3435 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3437 crWaitUntil(!pktin
);
3438 ret
= process_userpass_input(ssh
, in
, inlen
);
3442 c_write_str(ssh
, "\r\n");
3446 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3448 * Try public key authentication with the specified
3451 s
->tried_publickey
= 1;
3454 const char *error
= NULL
;
3455 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3458 c_write_str(ssh
, "Couldn't load private key from ");
3459 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3460 c_write_str(ssh
, " (");
3461 c_write_str(ssh
, error
);
3462 c_write_str(ssh
, ").\r\n");
3463 continue; /* go and try password */
3466 c_write_str(ssh
, "Wrong passphrase.\r\n");
3467 s
->tried_publickey
= 0;
3468 continue; /* try again */
3473 * Send a public key attempt.
3475 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3476 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3479 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3480 c_write_str(ssh
, "Server refused our public key.\r\n");
3481 continue; /* go and try password */
3483 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3484 bombout(("Bizarre response to offer of public key"));
3490 unsigned char buffer
[32];
3491 Bignum challenge
, response
;
3493 if ((challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3494 bombout(("Server's RSA challenge was badly formatted"));
3497 response
= rsadecrypt(challenge
, &s
->key
);
3498 freebn(s
->key
.private_exponent
);/* burn the evidence */
3500 for (i
= 0; i
< 32; i
++) {
3501 buffer
[i
] = bignum_byte(response
, 31 - i
);
3505 MD5Update(&md5c
, buffer
, 32);
3506 MD5Update(&md5c
, s
->session_id
, 16);
3507 MD5Final(buffer
, &md5c
);
3509 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3510 PKT_DATA
, buffer
, 16, PKT_END
);
3517 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3518 if (flags
& FLAG_VERBOSE
)
3519 c_write_str(ssh
, "Failed to authenticate with"
3520 " our public key.\r\n");
3521 continue; /* go and try password */
3522 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3523 bombout(("Bizarre response to RSA authentication response"));
3527 break; /* we're through! */
3529 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3531 * Defence against traffic analysis: we send a
3532 * whole bunch of packets containing strings of
3533 * different lengths. One of these strings is the
3534 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3535 * The others are all random data in
3536 * SSH1_MSG_IGNORE packets. This way a passive
3537 * listener can't tell which is the password, and
3538 * hence can't deduce the password length.
3540 * Anybody with a password length greater than 16
3541 * bytes is going to have enough entropy in their
3542 * password that a listener won't find it _that_
3543 * much help to know how long it is. So what we'll
3546 * - if password length < 16, we send 15 packets
3547 * containing string lengths 1 through 15
3549 * - otherwise, we let N be the nearest multiple
3550 * of 8 below the password length, and send 8
3551 * packets containing string lengths N through
3552 * N+7. This won't obscure the order of
3553 * magnitude of the password length, but it will
3554 * introduce a bit of extra uncertainty.
3556 * A few servers (the old 1.2.18 through 1.2.22)
3557 * can't deal with SSH1_MSG_IGNORE. For these
3558 * servers, we need an alternative defence. We make
3559 * use of the fact that the password is interpreted
3560 * as a C string: so we can append a NUL, then some
3563 * One server (a Cisco one) can deal with neither
3564 * SSH1_MSG_IGNORE _nor_ a padded password string.
3565 * For this server we are left with no defences
3566 * against password length sniffing.
3568 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3570 * The server can deal with SSH1_MSG_IGNORE, so
3571 * we can use the primary defence.
3573 int bottom
, top
, pwlen
, i
;
3576 pwlen
= strlen(s
->password
);
3578 bottom
= 0; /* zero length passwords are OK! :-) */
3581 bottom
= pwlen
& ~7;
3585 assert(pwlen
>= bottom
&& pwlen
<= top
);
3587 randomstr
= snewn(top
+ 1, char);
3589 for (i
= bottom
; i
<= top
; i
++) {
3591 defer_packet(ssh
, s
->pwpkt_type
,
3592 PKTT_PASSWORD
, PKT_STR
, s
->password
,
3593 PKTT_OTHER
, PKT_END
);
3595 for (j
= 0; j
< i
; j
++) {
3597 randomstr
[j
] = random_byte();
3598 } while (randomstr
[j
] == '\0');
3600 randomstr
[i
] = '\0';
3601 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3602 PKT_STR
, randomstr
, PKT_END
);
3605 logevent("Sending password with camouflage packets");
3606 ssh_pkt_defersend(ssh
);
3609 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3611 * The server can't deal with SSH1_MSG_IGNORE
3612 * but can deal with padded passwords, so we
3613 * can use the secondary defence.
3619 len
= strlen(s
->password
);
3620 if (len
< sizeof(string
)) {
3622 strcpy(string
, s
->password
);
3623 len
++; /* cover the zero byte */
3624 while (len
< sizeof(string
)) {
3625 string
[len
++] = (char) random_byte();
3630 logevent("Sending length-padded password");
3631 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3632 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3633 PKTT_OTHER
, PKT_END
);
3636 * The server has _both_
3637 * BUG_CHOKES_ON_SSH1_IGNORE and
3638 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3639 * therefore nothing we can do.
3642 len
= strlen(s
->password
);
3643 logevent("Sending unpadded password");
3644 send_packet(ssh
, s
->pwpkt_type
,
3645 PKTT_PASSWORD
, PKT_INT
, len
,
3646 PKT_DATA
, s
->password
, len
,
3647 PKTT_OTHER
, PKT_END
);
3650 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3651 PKT_STR
, s
->password
, PKTT_OTHER
, PKT_END
);
3654 logevent("Sent password");
3655 memset(s
->password
, 0, strlen(s
->password
));
3657 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3658 if (flags
& FLAG_VERBOSE
)
3659 c_write_str(ssh
, "Access denied\r\n");
3660 logevent("Authentication refused");
3661 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3662 bombout(("Strange packet received, type %d", pktin
->type
));
3667 logevent("Authentication successful");
3672 void sshfwd_close(struct ssh_channel
*c
)
3676 if (ssh
->state
== SSH_STATE_CLOSED
)
3679 if (c
&& !c
->closes
) {
3681 * If halfopen is true, we have sent
3682 * CHANNEL_OPEN for this channel, but it hasn't even been
3683 * acknowledged by the server. So we must set a close flag
3684 * on it now, and then when the server acks the channel
3685 * open, we can close it then.
3688 if (ssh
->version
== 1) {
3689 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3692 struct Packet
*pktout
;
3693 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3694 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
3695 ssh2_pkt_send(ssh
, pktout
);
3698 c
->closes
= 1; /* sent MSG_CLOSE */
3699 if (c
->type
== CHAN_X11
) {
3701 logevent("Forwarded X11 connection terminated");
3702 } else if (c
->type
== CHAN_SOCKDATA
||
3703 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3705 logevent("Forwarded port closed");
3710 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3714 if (ssh
->state
== SSH_STATE_CLOSED
)
3717 if (ssh
->version
== 1) {
3718 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3719 PKT_INT
, c
->remoteid
,
3721 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3722 PKTT_OTHER
, PKT_END
);
3724 * In SSH-1 we can return 0 here - implying that forwarded
3725 * connections are never individually throttled - because
3726 * the only circumstance that can cause throttling will be
3727 * the whole SSH connection backing up, in which case
3728 * _everything_ will be throttled as a whole.
3732 ssh2_add_channel_data(c
, buf
, len
);
3733 return ssh2_try_send(c
);
3737 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3741 if (ssh
->state
== SSH_STATE_CLOSED
)
3744 if (ssh
->version
== 1) {
3745 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3746 c
->v
.v1
.throttling
= 0;
3747 ssh1_throttle(ssh
, -1);
3750 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3754 static void ssh_queueing_handler(Ssh ssh
, struct Packet
*pktin
)
3756 struct queued_handler
*qh
= ssh
->qhead
;
3760 assert(pktin
->type
== qh
->msg1
|| pktin
->type
== qh
->msg2
);
3763 assert(ssh
->packet_dispatch
[qh
->msg1
] == ssh_queueing_handler
);
3764 ssh
->packet_dispatch
[qh
->msg1
] = NULL
;
3767 assert(ssh
->packet_dispatch
[qh
->msg2
] == ssh_queueing_handler
);
3768 ssh
->packet_dispatch
[qh
->msg2
] = NULL
;
3772 ssh
->qhead
= qh
->next
;
3774 if (ssh
->qhead
->msg1
> 0) {
3775 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg1
] == NULL
);
3776 ssh
->packet_dispatch
[ssh
->qhead
->msg1
] = ssh_queueing_handler
;
3778 if (ssh
->qhead
->msg2
> 0) {
3779 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg2
] == NULL
);
3780 ssh
->packet_dispatch
[ssh
->qhead
->msg2
] = ssh_queueing_handler
;
3783 ssh
->qhead
= ssh
->qtail
= NULL
;
3784 ssh
->packet_dispatch
[pktin
->type
] = NULL
;
3787 qh
->handler(ssh
, pktin
, qh
->ctx
);
3792 static void ssh_queue_handler(Ssh ssh
, int msg1
, int msg2
,
3793 chandler_fn_t handler
, void *ctx
)
3795 struct queued_handler
*qh
;
3797 qh
= snew(struct queued_handler
);
3800 qh
->handler
= handler
;
3804 if (ssh
->qtail
== NULL
) {
3808 assert(ssh
->packet_dispatch
[qh
->msg1
] == NULL
);
3809 ssh
->packet_dispatch
[qh
->msg1
] = ssh_queueing_handler
;
3812 assert(ssh
->packet_dispatch
[qh
->msg2
] == NULL
);
3813 ssh
->packet_dispatch
[qh
->msg2
] = ssh_queueing_handler
;
3816 ssh
->qtail
->next
= qh
;
3821 static void ssh_rportfwd_succfail(Ssh ssh
, struct Packet
*pktin
, void *ctx
)
3823 struct ssh_rportfwd
*rpf
, *pf
= (struct ssh_rportfwd
*)ctx
;
3825 if (pktin
->type
== (ssh
->version
== 1 ? SSH1_SMSG_SUCCESS
:
3826 SSH2_MSG_REQUEST_SUCCESS
)) {
3827 logeventf(ssh
, "Remote port forwarding from %s enabled",
3830 logeventf(ssh
, "Remote port forwarding from %s refused",
3833 rpf
= del234(ssh
->rportfwds
, pf
);
3839 static void ssh_setup_portfwd(Ssh ssh
, const Config
*cfg
)
3841 const char *portfwd_strptr
= cfg
->portfwd
;
3842 struct ssh_portfwd
*epf
;
3845 if (!ssh
->portfwds
) {
3846 ssh
->portfwds
= newtree234(ssh_portcmp
);
3849 * Go through the existing port forwardings and tag them
3850 * with status==DESTROY. Any that we want to keep will be
3851 * re-enabled (status==KEEP) as we go through the
3852 * configuration and find out which bits are the same as
3855 struct ssh_portfwd
*epf
;
3857 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3858 epf
->status
= DESTROY
;
3861 while (*portfwd_strptr
) {
3862 char address_family
, type
;
3863 int sport
,dport
,sserv
,dserv
;
3864 char sports
[256], dports
[256], saddr
[256], host
[256];
3867 address_family
= 'A';
3869 if (*portfwd_strptr
== 'A' ||
3870 *portfwd_strptr
== '4' ||
3871 *portfwd_strptr
== '6')
3872 address_family
= *portfwd_strptr
++;
3873 if (*portfwd_strptr
== 'L' ||
3874 *portfwd_strptr
== 'R' ||
3875 *portfwd_strptr
== 'D')
3876 type
= *portfwd_strptr
++;
3881 while (*portfwd_strptr
&& *portfwd_strptr
!= '\t') {
3882 if (*portfwd_strptr
== ':') {
3884 * We've seen a colon in the middle of the
3885 * source port number. This means that
3886 * everything we've seen until now is the
3887 * source _address_, so we'll move it into
3888 * saddr and start sports from the beginning
3893 if (ssh
->version
== 1 && type
== 'R') {
3894 logeventf(ssh
, "SSH-1 cannot handle remote source address "
3895 "spec \"%s\"; ignoring", sports
);
3897 strcpy(saddr
, sports
);
3900 if (n
< lenof(sports
)-1) sports
[n
++] = *portfwd_strptr
++;
3904 if (*portfwd_strptr
== '\t')
3907 while (*portfwd_strptr
&& *portfwd_strptr
!= ':') {
3908 if (n
< lenof(host
)-1) host
[n
++] = *portfwd_strptr
++;
3911 if (*portfwd_strptr
== ':')
3914 while (*portfwd_strptr
) {
3915 if (n
< lenof(dports
)-1) dports
[n
++] = *portfwd_strptr
++;
3919 dport
= atoi(dports
);
3923 dport
= net_service_lookup(dports
);
3925 logeventf(ssh
, "Service lookup failed for destination"
3926 " port \"%s\"", dports
);
3930 while (*portfwd_strptr
) portfwd_strptr
++;
3934 portfwd_strptr
++; /* eat the NUL and move to next one */
3936 sport
= atoi(sports
);
3940 sport
= net_service_lookup(sports
);
3942 logeventf(ssh
, "Service lookup failed for source"
3943 " port \"%s\"", sports
);
3946 if (sport
&& dport
) {
3947 /* Set up a description of the source port. */
3948 struct ssh_portfwd
*pfrec
, *epfrec
;
3950 pfrec
= snew(struct ssh_portfwd
);
3952 pfrec
->saddr
= *saddr ?
dupstr(saddr
) : NULL
;
3953 pfrec
->sserv
= sserv ?
dupstr(sports
) : NULL
;
3954 pfrec
->sport
= sport
;
3955 pfrec
->daddr
= *host ?
dupstr(host
) : NULL
;
3956 pfrec
->dserv
= dserv ?
dupstr(dports
) : NULL
;
3957 pfrec
->dport
= dport
;
3958 pfrec
->local
= NULL
;
3959 pfrec
->remote
= NULL
;
3960 pfrec
->addressfamily
= (address_family
== '4' ? ADDRTYPE_IPV4
:
3961 address_family
== '6' ? ADDRTYPE_IPV6
:
3964 epfrec
= add234(ssh
->portfwds
, pfrec
);
3965 if (epfrec
!= pfrec
) {
3967 * We already have a port forwarding with precisely
3968 * these parameters. Hence, no need to do anything;
3969 * simply tag the existing one as KEEP.
3971 epfrec
->status
= KEEP
;
3972 free_portfwd(pfrec
);
3974 pfrec
->status
= CREATE
;
3980 * Now go through and destroy any port forwardings which were
3983 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3984 if (epf
->status
== DESTROY
) {
3987 message
= dupprintf("%s port forwarding from %s%s%d",
3988 epf
->type
== 'L' ?
"local" :
3989 epf
->type
== 'R' ?
"remote" : "dynamic",
3990 epf
->saddr ? epf
->saddr
: "",
3991 epf
->saddr ?
":" : "",
3994 if (epf
->type
!= 'D') {
3995 char *msg2
= dupprintf("%s to %s:%d", message
,
3996 epf
->daddr
, epf
->dport
);
4001 logeventf(ssh
, "Cancelling %s", message
);
4005 struct ssh_rportfwd
*rpf
= epf
->remote
;
4006 struct Packet
*pktout
;
4009 * Cancel the port forwarding at the server
4012 if (ssh
->version
== 1) {
4014 * We cannot cancel listening ports on the
4015 * server side in SSH-1! There's no message
4016 * to support it. Instead, we simply remove
4017 * the rportfwd record from the local end
4018 * so that any connections the server tries
4019 * to make on it are rejected.
4022 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
4023 ssh2_pkt_addstring(pktout
, "cancel-tcpip-forward");
4024 ssh2_pkt_addbool(pktout
, 0);/* _don't_ want reply */
4026 ssh2_pkt_addstring(pktout
, epf
->saddr
);
4027 } else if (ssh
->cfg
.rport_acceptall
) {
4028 /* XXX: ssh->cfg.rport_acceptall may not represent
4029 * what was used to open the original connection,
4030 * since it's reconfigurable. */
4031 ssh2_pkt_addstring(pktout
, "0.0.0.0");
4033 ssh2_pkt_addstring(pktout
, "127.0.0.1");
4035 ssh2_pkt_adduint32(pktout
, epf
->sport
);
4036 ssh2_pkt_send(ssh
, pktout
);
4039 del234(ssh
->rportfwds
, rpf
);
4041 } else if (epf
->local
) {
4042 pfd_terminate(epf
->local
);
4045 delpos234(ssh
->portfwds
, i
);
4047 i
--; /* so we don't skip one in the list */
4051 * And finally, set up any new port forwardings (status==CREATE).
4053 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
4054 if (epf
->status
== CREATE
) {
4055 char *sportdesc
, *dportdesc
;
4056 sportdesc
= dupprintf("%s%s%s%s%d%s",
4057 epf
->saddr ? epf
->saddr
: "",
4058 epf
->saddr ?
":" : "",
4059 epf
->sserv ? epf
->sserv
: "",
4060 epf
->sserv ?
"(" : "",
4062 epf
->sserv ?
")" : "");
4063 if (epf
->type
== 'D') {
4066 dportdesc
= dupprintf("%s:%s%s%d%s",
4068 epf
->dserv ? epf
->dserv
: "",
4069 epf
->dserv ?
"(" : "",
4071 epf
->dserv ?
")" : "");
4074 if (epf
->type
== 'L') {
4075 const char *err
= pfd_addforward(epf
->daddr
, epf
->dport
,
4076 epf
->saddr
, epf
->sport
,
4079 epf
->addressfamily
);
4081 logeventf(ssh
, "Local %sport %s forwarding to %s%s%s",
4082 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
4083 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
4084 sportdesc
, dportdesc
,
4085 err ?
" failed: " : "", err ? err
: "");
4086 } else if (epf
->type
== 'D') {
4087 const char *err
= pfd_addforward(NULL
, -1,
4088 epf
->saddr
, epf
->sport
,
4091 epf
->addressfamily
);
4093 logeventf(ssh
, "Local %sport %s SOCKS dynamic forwarding%s%s",
4094 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
4095 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
4097 err ?
" failed: " : "", err ? err
: "");
4099 struct ssh_rportfwd
*pf
;
4102 * Ensure the remote port forwardings tree exists.
4104 if (!ssh
->rportfwds
) {
4105 if (ssh
->version
== 1)
4106 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
4108 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
4111 pf
= snew(struct ssh_rportfwd
);
4112 strncpy(pf
->dhost
, epf
->daddr
, lenof(pf
->dhost
)-1);
4113 pf
->dhost
[lenof(pf
->dhost
)-1] = '\0';
4114 pf
->dport
= epf
->dport
;
4115 pf
->sport
= epf
->sport
;
4116 if (add234(ssh
->rportfwds
, pf
) != pf
) {
4117 logeventf(ssh
, "Duplicate remote port forwarding to %s:%d",
4118 epf
->daddr
, epf
->dport
);
4121 logeventf(ssh
, "Requesting remote port %s"
4122 " forward to %s", sportdesc
, dportdesc
);
4124 pf
->sportdesc
= sportdesc
;
4129 if (ssh
->version
== 1) {
4130 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
4131 PKT_INT
, epf
->sport
,
4132 PKT_STR
, epf
->daddr
,
4133 PKT_INT
, epf
->dport
,
4135 ssh_queue_handler(ssh
, SSH1_SMSG_SUCCESS
,
4137 ssh_rportfwd_succfail
, pf
);
4139 struct Packet
*pktout
;
4140 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
4141 ssh2_pkt_addstring(pktout
, "tcpip-forward");
4142 ssh2_pkt_addbool(pktout
, 1);/* want reply */
4144 ssh2_pkt_addstring(pktout
, epf
->saddr
);
4145 } else if (cfg
->rport_acceptall
) {
4146 ssh2_pkt_addstring(pktout
, "0.0.0.0");
4148 ssh2_pkt_addstring(pktout
, "127.0.0.1");
4150 ssh2_pkt_adduint32(pktout
, epf
->sport
);
4151 ssh2_pkt_send(ssh
, pktout
);
4153 ssh_queue_handler(ssh
, SSH2_MSG_REQUEST_SUCCESS
,
4154 SSH2_MSG_REQUEST_FAILURE
,
4155 ssh_rportfwd_succfail
, pf
);
4164 static void ssh1_smsg_stdout_stderr_data(Ssh ssh
, struct Packet
*pktin
)
4167 int stringlen
, bufsize
;
4169 ssh_pkt_getstring(pktin
, &string
, &stringlen
);
4170 if (string
== NULL
) {
4171 bombout(("Incoming terminal data packet was badly formed"));
4175 bufsize
= from_backend(ssh
->frontend
, pktin
->type
== SSH1_SMSG_STDERR_DATA
,
4177 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4178 ssh
->v1_stdout_throttling
= 1;
4179 ssh1_throttle(ssh
, +1);
4183 static void ssh1_smsg_x11_open(Ssh ssh
, struct Packet
*pktin
)
4185 /* Remote side is trying to open a channel to talk to our
4186 * X-Server. Give them back a local channel number. */
4187 struct ssh_channel
*c
;
4188 int remoteid
= ssh_pkt_getuint32(pktin
);
4190 logevent("Received X11 connect request");
4191 /* Refuse if X11 forwarding is disabled. */
4192 if (!ssh
->X11_fwd_enabled
) {
4193 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4194 PKT_INT
, remoteid
, PKT_END
);
4195 logevent("Rejected X11 connect request");
4197 c
= snew(struct ssh_channel
);
4200 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
4201 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
4202 logevent("Opening X11 forward connection failed");
4204 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4205 PKT_INT
, remoteid
, PKT_END
);
4208 ("Opening X11 forward connection succeeded");
4209 c
->remoteid
= remoteid
;
4210 c
->halfopen
= FALSE
;
4211 c
->localid
= alloc_channel_id(ssh
);
4213 c
->v
.v1
.throttling
= 0;
4214 c
->type
= CHAN_X11
; /* identify channel type */
4215 add234(ssh
->channels
, c
);
4216 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4217 PKT_INT
, c
->remoteid
, PKT_INT
,
4218 c
->localid
, PKT_END
);
4219 logevent("Opened X11 forward channel");
4224 static void ssh1_smsg_agent_open(Ssh ssh
, struct Packet
*pktin
)
4226 /* Remote side is trying to open a channel to talk to our
4227 * agent. Give them back a local channel number. */
4228 struct ssh_channel
*c
;
4229 int remoteid
= ssh_pkt_getuint32(pktin
);
4231 /* Refuse if agent forwarding is disabled. */
4232 if (!ssh
->agentfwd_enabled
) {
4233 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4234 PKT_INT
, remoteid
, PKT_END
);
4236 c
= snew(struct ssh_channel
);
4238 c
->remoteid
= remoteid
;
4239 c
->halfopen
= FALSE
;
4240 c
->localid
= alloc_channel_id(ssh
);
4242 c
->v
.v1
.throttling
= 0;
4243 c
->type
= CHAN_AGENT
; /* identify channel type */
4244 c
->u
.a
.lensofar
= 0;
4245 add234(ssh
->channels
, c
);
4246 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4247 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
4252 static void ssh1_msg_port_open(Ssh ssh
, struct Packet
*pktin
)
4254 /* Remote side is trying to open a channel to talk to a
4255 * forwarded port. Give them back a local channel number. */
4256 struct ssh_channel
*c
;
4257 struct ssh_rportfwd pf
, *pfp
;
4262 c
= snew(struct ssh_channel
);
4265 remoteid
= ssh_pkt_getuint32(pktin
);
4266 ssh_pkt_getstring(pktin
, &host
, &hostsize
);
4267 port
= ssh_pkt_getuint32(pktin
);
4269 if (hostsize
>= lenof(pf
.dhost
))
4270 hostsize
= lenof(pf
.dhost
)-1;
4271 memcpy(pf
.dhost
, host
, hostsize
);
4272 pf
.dhost
[hostsize
] = '\0';
4274 pfp
= find234(ssh
->rportfwds
, &pf
, NULL
);
4277 logeventf(ssh
, "Rejected remote port open request for %s:%d",
4279 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4280 PKT_INT
, remoteid
, PKT_END
);
4282 logeventf(ssh
, "Received remote port open request for %s:%d",
4284 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
4285 c
, &ssh
->cfg
, pfp
->pfrec
->addressfamily
);
4287 logeventf(ssh
, "Port open failed: %s", e
);
4289 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4290 PKT_INT
, remoteid
, PKT_END
);
4292 c
->remoteid
= remoteid
;
4293 c
->halfopen
= FALSE
;
4294 c
->localid
= alloc_channel_id(ssh
);
4296 c
->v
.v1
.throttling
= 0;
4297 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
4298 add234(ssh
->channels
, c
);
4299 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4300 PKT_INT
, c
->remoteid
, PKT_INT
,
4301 c
->localid
, PKT_END
);
4302 logevent("Forwarded port opened successfully");
4307 static void ssh1_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
4309 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4310 unsigned int localid
= ssh_pkt_getuint32(pktin
);
4311 struct ssh_channel
*c
;
4313 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4314 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4315 c
->remoteid
= localid
;
4316 c
->halfopen
= FALSE
;
4317 c
->type
= CHAN_SOCKDATA
;
4318 c
->v
.v1
.throttling
= 0;
4319 pfd_confirm(c
->u
.pfd
.s
);
4322 if (c
&& c
->closes
) {
4324 * We have a pending close on this channel,
4325 * which we decided on before the server acked
4326 * the channel open. So now we know the
4327 * remoteid, we can close it again.
4329 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
4330 PKT_INT
, c
->remoteid
, PKT_END
);
4334 static void ssh1_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
4336 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4337 struct ssh_channel
*c
;
4339 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4340 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4341 logevent("Forwarded connection refused by server");
4342 pfd_close(c
->u
.pfd
.s
);
4343 del234(ssh
->channels
, c
);
4348 static void ssh1_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
4350 /* Remote side closes a channel. */
4351 unsigned i
= ssh_pkt_getuint32(pktin
);
4352 struct ssh_channel
*c
;
4353 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4354 if (c
&& !c
->halfopen
) {
4357 (pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
4359 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
4360 logevent("Forwarded X11 connection terminated");
4361 assert(c
->u
.x11
.s
!= NULL
);
4362 x11_close(c
->u
.x11
.s
);
4365 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
4366 logevent("Forwarded port closed");
4367 assert(c
->u
.pfd
.s
!= NULL
);
4368 pfd_close(c
->u
.pfd
.s
);
4372 c
->closes
|= (closetype
<< 2); /* seen this message */
4373 if (!(c
->closes
& closetype
)) {
4374 send_packet(ssh
, pktin
->type
, PKT_INT
, c
->remoteid
,
4376 c
->closes
|= closetype
; /* sent it too */
4379 if (c
->closes
== 15) {
4380 del234(ssh
->channels
, c
);
4384 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4385 pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
4386 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
4391 static void ssh1_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
4393 /* Data sent down one of our channels. */
4394 int i
= ssh_pkt_getuint32(pktin
);
4397 struct ssh_channel
*c
;
4399 ssh_pkt_getstring(pktin
, &p
, &len
);
4401 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4406 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
4409 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
4412 /* Data for an agent message. Buffer it. */
4414 if (c
->u
.a
.lensofar
< 4) {
4415 unsigned int l
= min(4 - c
->u
.a
.lensofar
, len
);
4416 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
4420 c
->u
.a
.lensofar
+= l
;
4422 if (c
->u
.a
.lensofar
== 4) {
4424 4 + GET_32BIT(c
->u
.a
.msglen
);
4425 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
4427 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
4429 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
4431 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
4433 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
4437 c
->u
.a
.lensofar
+= l
;
4439 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
4442 if (agent_query(c
->u
.a
.message
,
4445 ssh_agentf_callback
, c
))
4446 ssh_agentf_callback(c
, reply
, replylen
);
4447 sfree(c
->u
.a
.message
);
4448 c
->u
.a
.lensofar
= 0;
4451 bufsize
= 0; /* agent channels never back up */
4454 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4455 c
->v
.v1
.throttling
= 1;
4456 ssh1_throttle(ssh
, +1);
4461 static void ssh1_smsg_exit_status(Ssh ssh
, struct Packet
*pktin
)
4463 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
4464 logeventf(ssh
, "Server sent command exit status %d", ssh
->exitcode
);
4465 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
4467 * In case `helpful' firewalls or proxies tack
4468 * extra human-readable text on the end of the
4469 * session which we might mistake for another
4470 * encrypted packet, we close the session once
4471 * we've sent EXIT_CONFIRMATION.
4473 ssh
->close_expected
= TRUE
;
4474 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4477 static void do_ssh1_connection(Ssh ssh
, unsigned char *in
, int inlen
,
4478 struct Packet
*pktin
)
4480 crBegin(ssh
->do_ssh1_connection_crstate
);
4482 ssh
->packet_dispatch
[SSH1_SMSG_STDOUT_DATA
] =
4483 ssh
->packet_dispatch
[SSH1_SMSG_STDERR_DATA
] =
4484 ssh1_smsg_stdout_stderr_data
;
4486 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
] =
4487 ssh1_msg_channel_open_confirmation
;
4488 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_FAILURE
] =
4489 ssh1_msg_channel_open_failure
;
4490 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE
] =
4491 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
] =
4492 ssh1_msg_channel_close
;
4493 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_DATA
] = ssh1_msg_channel_data
;
4494 ssh
->packet_dispatch
[SSH1_SMSG_EXIT_STATUS
] = ssh1_smsg_exit_status
;
4496 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
4497 logevent("Requesting agent forwarding");
4498 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
4502 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4503 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4504 bombout(("Protocol confusion"));
4506 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4507 logevent("Agent forwarding refused");
4509 logevent("Agent forwarding enabled");
4510 ssh
->agentfwd_enabled
= TRUE
;
4511 ssh
->packet_dispatch
[SSH1_SMSG_AGENT_OPEN
] = ssh1_smsg_agent_open
;
4515 if (ssh
->cfg
.x11_forward
) {
4516 char proto
[20], data
[64];
4517 logevent("Requesting X11 forwarding");
4518 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
4519 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
4520 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
4521 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
4522 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4523 PKT_STR
, proto
, PKT_STR
, data
,
4524 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
4527 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4528 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
4533 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4534 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4535 bombout(("Protocol confusion"));
4537 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4538 logevent("X11 forwarding refused");
4540 logevent("X11 forwarding enabled");
4541 ssh
->X11_fwd_enabled
= TRUE
;
4542 ssh
->packet_dispatch
[SSH1_SMSG_X11_OPEN
] = ssh1_smsg_x11_open
;
4546 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
4547 ssh
->packet_dispatch
[SSH1_MSG_PORT_OPEN
] = ssh1_msg_port_open
;
4549 if (!ssh
->cfg
.nopty
) {
4550 /* Unpick the terminal-speed string. */
4551 /* XXX perhaps we should allow no speeds to be sent. */
4552 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
4553 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
4554 /* Send the pty request. */
4555 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
4556 PKT_STR
, ssh
->cfg
.termtype
,
4557 PKT_INT
, ssh
->term_height
,
4558 PKT_INT
, ssh
->term_width
,
4559 PKT_INT
, 0, PKT_INT
, 0, /* width,height in pixels */
4560 PKT_CHAR
, 192, PKT_INT
, ssh
->ispeed
, /* TTY_OP_ISPEED */
4561 PKT_CHAR
, 193, PKT_INT
, ssh
->ospeed
, /* TTY_OP_OSPEED */
4562 PKT_CHAR
, 0, PKT_END
);
4563 ssh
->state
= SSH_STATE_INTERMED
;
4567 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4568 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4569 bombout(("Protocol confusion"));
4571 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4572 c_write_str(ssh
, "Server refused to allocate pty\r\n");
4573 ssh
->editing
= ssh
->echoing
= 1;
4575 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
4576 ssh
->ospeed
, ssh
->ispeed
);
4578 ssh
->editing
= ssh
->echoing
= 1;
4581 if (ssh
->cfg
.compression
) {
4582 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
4586 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4587 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4588 bombout(("Protocol confusion"));
4590 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4591 c_write_str(ssh
, "Server refused to compress\r\n");
4593 logevent("Started compression");
4594 ssh
->v1_compressing
= TRUE
;
4595 ssh
->cs_comp_ctx
= zlib_compress_init();
4596 logevent("Initialised zlib (RFC1950) compression");
4597 ssh
->sc_comp_ctx
= zlib_decompress_init();
4598 logevent("Initialised zlib (RFC1950) decompression");
4602 * Start the shell or command.
4604 * Special case: if the first-choice command is an SSH-2
4605 * subsystem (hence not usable here) and the second choice
4606 * exists, we fall straight back to that.
4609 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
4611 if (!cmd
) cmd
= ssh
->cfg
.remote_cmd
;
4613 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
4614 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
4615 ssh
->fallback_cmd
= TRUE
;
4618 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
4620 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
4621 logevent("Started session");
4624 ssh
->state
= SSH_STATE_SESSION
;
4625 if (ssh
->size_needed
)
4626 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
4627 if (ssh
->eof_needed
)
4628 ssh_special(ssh
, TS_EOF
);
4631 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
4633 ssh
->channels
= newtree234(ssh_channelcmp
);
4637 * By this point, most incoming packets are already being
4638 * handled by the dispatch table, and we need only pay
4639 * attention to the unusual ones.
4644 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
4645 /* may be from EXEC_SHELL on some servers */
4646 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4647 /* may be from EXEC_SHELL on some servers
4648 * if no pty is available or in other odd cases. Ignore */
4650 bombout(("Strange packet received: type %d", pktin
->type
));
4655 int len
= min(inlen
, 512);
4656 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4657 PKT_INT
, len
, PKT_DATA
, in
, len
,
4658 PKTT_OTHER
, PKT_END
);
4669 * Handle the top-level SSH-2 protocol.
4671 static void ssh1_msg_debug(Ssh ssh
, struct Packet
*pktin
)
4676 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4677 logeventf(ssh
, "Remote debug message: %.*s", msglen
, msg
);
4680 static void ssh1_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
4682 /* log reason code in disconnect message */
4686 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4687 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen
, msg
));
4690 static void ssh_msg_ignore(Ssh ssh
, struct Packet
*pktin
)
4692 /* Do nothing, because we're ignoring it! Duhh. */
4695 static void ssh1_protocol_setup(Ssh ssh
)
4700 * Most messages are handled by the coroutines.
4702 for (i
= 0; i
< 256; i
++)
4703 ssh
->packet_dispatch
[i
] = NULL
;
4706 * These special message types we install handlers for.
4708 ssh
->packet_dispatch
[SSH1_MSG_DISCONNECT
] = ssh1_msg_disconnect
;
4709 ssh
->packet_dispatch
[SSH1_MSG_IGNORE
] = ssh_msg_ignore
;
4710 ssh
->packet_dispatch
[SSH1_MSG_DEBUG
] = ssh1_msg_debug
;
4713 static void ssh1_protocol(Ssh ssh
, void *vin
, int inlen
,
4714 struct Packet
*pktin
)
4716 unsigned char *in
=(unsigned char*)vin
;
4717 if (ssh
->state
== SSH_STATE_CLOSED
)
4720 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
4721 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
4725 if (!ssh
->protocol_initial_phase_done
) {
4726 if (do_ssh1_login(ssh
, in
, inlen
, pktin
))
4727 ssh
->protocol_initial_phase_done
= TRUE
;
4732 do_ssh1_connection(ssh
, in
, inlen
, pktin
);
4736 * Utility routine for decoding comma-separated strings in KEXINIT.
4738 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
4741 if (!needle
|| !haystack
) /* protect against null pointers */
4743 needlen
= strlen(needle
);
4746 * Is it at the start of the string?
4748 if (haylen
>= needlen
&& /* haystack is long enough */
4749 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4750 (haylen
== needlen
|| haystack
[needlen
] == ',')
4751 /* either , or EOS follows */
4755 * If not, search for the next comma and resume after that.
4756 * If no comma found, terminate.
4758 while (haylen
> 0 && *haystack
!= ',')
4759 haylen
--, haystack
++;
4762 haylen
--, haystack
++; /* skip over comma itself */
4767 * Similar routine for checking whether we have the first string in a list.
4769 static int first_in_commasep_string(char *needle
, char *haystack
, int haylen
)
4772 if (!needle
|| !haystack
) /* protect against null pointers */
4774 needlen
= strlen(needle
);
4776 * Is it at the start of the string?
4778 if (haylen
>= needlen
&& /* haystack is long enough */
4779 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4780 (haylen
== needlen
|| haystack
[needlen
] == ',')
4781 /* either , or EOS follows */
4789 * SSH-2 key creation method.
4791 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
4792 unsigned char *sessid
, char chr
,
4793 unsigned char *keyspace
)
4796 /* First 20 bytes. */
4798 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4800 SHA_Bytes(&s
, H
, 20);
4801 SHA_Bytes(&s
, &chr
, 1);
4802 SHA_Bytes(&s
, sessid
, 20);
4803 SHA_Final(&s
, keyspace
);
4804 /* Next 20 bytes. */
4806 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4808 SHA_Bytes(&s
, H
, 20);
4809 SHA_Bytes(&s
, keyspace
, 20);
4810 SHA_Final(&s
, keyspace
+ 20);
4814 * Handle the SSH-2 transport layer.
4816 static int do_ssh2_transport(Ssh ssh
, void *vin
, int inlen
,
4817 struct Packet
*pktin
)
4819 unsigned char *in
= (unsigned char *)vin
;
4820 struct do_ssh2_transport_state
{
4821 int nbits
, pbits
, warn_kex
, warn_cscipher
, warn_sccipher
;
4822 Bignum p
, g
, e
, f
, K
;
4823 int kex_init_value
, kex_reply_value
;
4824 const struct ssh_mac
**maclist
;
4826 const struct ssh2_cipher
*cscipher_tobe
;
4827 const struct ssh2_cipher
*sccipher_tobe
;
4828 const struct ssh_mac
*csmac_tobe
;
4829 const struct ssh_mac
*scmac_tobe
;
4830 const struct ssh_compress
*cscomp_tobe
;
4831 const struct ssh_compress
*sccomp_tobe
;
4832 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4833 int hostkeylen
, siglen
;
4834 void *hkey
; /* actual host key */
4835 unsigned char exchange_hash
[20];
4836 int n_preferred_kex
;
4837 const struct ssh_kex
*preferred_kex
[KEX_MAX
];
4838 int n_preferred_ciphers
;
4839 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
4840 const struct ssh_compress
*preferred_comp
;
4841 int got_session_id
, activated_authconn
;
4842 struct Packet
*pktout
;
4847 crState(do_ssh2_transport_state
);
4849 crBegin(ssh
->do_ssh2_transport_crstate
);
4851 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
4852 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
4853 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
4855 s
->got_session_id
= s
->activated_authconn
= FALSE
;
4858 * Be prepared to work around the buggy MAC problem.
4860 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
4861 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
4863 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
4866 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_KEX_MASK
;
4868 int i
, j
, commalist_started
;
4871 * Set up the preferred key exchange. (NULL => warn below here)
4873 s
->n_preferred_kex
= 0;
4874 for (i
= 0; i
< KEX_MAX
; i
++) {
4875 switch (ssh
->cfg
.ssh_kexlist
[i
]) {
4877 s
->preferred_kex
[s
->n_preferred_kex
++] =
4878 &ssh_diffiehellman_gex
;
4881 s
->preferred_kex
[s
->n_preferred_kex
++] =
4882 &ssh_diffiehellman_group14
;
4885 s
->preferred_kex
[s
->n_preferred_kex
++] =
4886 &ssh_diffiehellman_group1
;
4889 /* Flag for later. Don't bother if it's the last in
4891 if (i
< KEX_MAX
- 1) {
4892 s
->preferred_kex
[s
->n_preferred_kex
++] = NULL
;
4899 * Set up the preferred ciphers. (NULL => warn below here)
4901 s
->n_preferred_ciphers
= 0;
4902 for (i
= 0; i
< CIPHER_MAX
; i
++) {
4903 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
4904 case CIPHER_BLOWFISH
:
4905 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
4908 if (ssh
->cfg
.ssh2_des_cbc
) {
4909 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
4913 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
4916 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
4918 case CIPHER_ARCFOUR
:
4919 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_arcfour
;
4922 /* Flag for later. Don't bother if it's the last in
4924 if (i
< CIPHER_MAX
- 1) {
4925 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
4932 * Set up preferred compression.
4934 if (ssh
->cfg
.compression
)
4935 s
->preferred_comp
= &ssh_zlib
;
4937 s
->preferred_comp
= &ssh_comp_none
;
4940 * Enable queueing of outgoing auth- or connection-layer
4941 * packets while we are in the middle of a key exchange.
4943 ssh
->queueing
= TRUE
;
4946 * Flag that KEX is in progress.
4948 ssh
->kex_in_progress
= TRUE
;
4951 * Construct and send our key exchange packet.
4953 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEXINIT
);
4954 for (i
= 0; i
< 16; i
++)
4955 ssh2_pkt_addbyte(s
->pktout
, (unsigned char) random_byte());
4956 /* List key exchange algorithms. */
4957 ssh2_pkt_addstring_start(s
->pktout
);
4958 commalist_started
= 0;
4959 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4960 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4961 if (!k
) continue; /* warning flag */
4962 if (commalist_started
)
4963 ssh2_pkt_addstring_str(s
->pktout
, ",");
4964 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_kex
[i
]->name
);
4965 commalist_started
= 1;
4967 /* List server host key algorithms. */
4968 ssh2_pkt_addstring_start(s
->pktout
);
4969 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4970 ssh2_pkt_addstring_str(s
->pktout
, hostkey_algs
[i
]->name
);
4971 if (i
< lenof(hostkey_algs
) - 1)
4972 ssh2_pkt_addstring_str(s
->pktout
, ",");
4974 /* List client->server encryption algorithms. */
4975 ssh2_pkt_addstring_start(s
->pktout
);
4976 commalist_started
= 0;
4977 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4978 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4979 if (!c
) continue; /* warning flag */
4980 for (j
= 0; j
< c
->nciphers
; j
++) {
4981 if (commalist_started
)
4982 ssh2_pkt_addstring_str(s
->pktout
, ",");
4983 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4984 commalist_started
= 1;
4987 /* List server->client encryption algorithms. */
4988 ssh2_pkt_addstring_start(s
->pktout
);
4989 commalist_started
= 0;
4990 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4991 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4992 if (!c
) continue; /* warning flag */
4993 for (j
= 0; j
< c
->nciphers
; j
++) {
4994 if (commalist_started
)
4995 ssh2_pkt_addstring_str(s
->pktout
, ",");
4996 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4997 commalist_started
= 1;
5000 /* List client->server MAC algorithms. */
5001 ssh2_pkt_addstring_start(s
->pktout
);
5002 for (i
= 0; i
< s
->nmacs
; i
++) {
5003 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
5004 if (i
< s
->nmacs
- 1)
5005 ssh2_pkt_addstring_str(s
->pktout
, ",");
5007 /* List server->client MAC algorithms. */
5008 ssh2_pkt_addstring_start(s
->pktout
);
5009 for (i
= 0; i
< s
->nmacs
; i
++) {
5010 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
5011 if (i
< s
->nmacs
- 1)
5012 ssh2_pkt_addstring_str(s
->pktout
, ",");
5014 /* List client->server compression algorithms. */
5015 ssh2_pkt_addstring_start(s
->pktout
);
5016 assert(lenof(compressions
) > 1);
5017 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
5018 for (i
= 0; i
< lenof(compressions
); i
++) {
5019 const struct ssh_compress
*c
= compressions
[i
];
5020 if (c
!= s
->preferred_comp
) {
5021 ssh2_pkt_addstring_str(s
->pktout
, ",");
5022 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
5025 /* List server->client compression algorithms. */
5026 ssh2_pkt_addstring_start(s
->pktout
);
5027 assert(lenof(compressions
) > 1);
5028 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
5029 for (i
= 0; i
< lenof(compressions
); i
++) {
5030 const struct ssh_compress
*c
= compressions
[i
];
5031 if (c
!= s
->preferred_comp
) {
5032 ssh2_pkt_addstring_str(s
->pktout
, ",");
5033 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
5036 /* List client->server languages. Empty list. */
5037 ssh2_pkt_addstring_start(s
->pktout
);
5038 /* List server->client languages. Empty list. */
5039 ssh2_pkt_addstring_start(s
->pktout
);
5040 /* First KEX packet does _not_ follow, because we're not that brave. */
5041 ssh2_pkt_addbool(s
->pktout
, FALSE
);
5043 ssh2_pkt_adduint32(s
->pktout
, 0);
5046 ssh
->exhash
= ssh
->exhashbase
;
5047 sha_string(&ssh
->exhash
, s
->pktout
->data
+ 5, s
->pktout
->length
- 5);
5049 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5053 if (pktin
->length
> 5)
5054 sha_string(&ssh
->exhash
, pktin
->data
+ 5, pktin
->length
- 5);
5057 * Now examine the other side's KEXINIT to see what we're up
5061 char *str
, *preferred
;
5064 if (pktin
->type
!= SSH2_MSG_KEXINIT
) {
5065 bombout(("expected key exchange packet from server"));
5069 ssh
->hostkey
= NULL
;
5070 s
->cscipher_tobe
= NULL
;
5071 s
->sccipher_tobe
= NULL
;
5072 s
->csmac_tobe
= NULL
;
5073 s
->scmac_tobe
= NULL
;
5074 s
->cscomp_tobe
= NULL
;
5075 s
->sccomp_tobe
= NULL
;
5076 s
->warn_kex
= s
->warn_cscipher
= s
->warn_sccipher
= FALSE
;
5078 pktin
->savedpos
+= 16; /* skip garbage cookie */
5079 ssh_pkt_getstring(pktin
, &str
, &len
); /* key exchange algorithms */
5082 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
5083 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
5087 if (!preferred
) preferred
= k
->name
;
5088 if (in_commasep_string(k
->name
, str
, len
))
5095 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
5096 str ? str
: "(null)"));
5100 * Note that the server's guess is considered wrong if it doesn't match
5101 * the first algorithm in our list, even if it's still the algorithm
5104 s
->guessok
= first_in_commasep_string(preferred
, str
, len
);
5105 ssh_pkt_getstring(pktin
, &str
, &len
); /* host key algorithms */
5106 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
5107 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
5108 ssh
->hostkey
= hostkey_algs
[i
];
5112 s
->guessok
= s
->guessok
&&
5113 first_in_commasep_string(hostkey_algs
[0]->name
, str
, len
);
5114 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server cipher */
5115 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5116 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5118 s
->warn_cscipher
= TRUE
;
5120 for (j
= 0; j
< c
->nciphers
; j
++) {
5121 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
5122 s
->cscipher_tobe
= c
->list
[j
];
5127 if (s
->cscipher_tobe
)
5130 if (!s
->cscipher_tobe
) {
5131 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
5132 str ? str
: "(null)"));
5136 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client cipher */
5137 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5138 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5140 s
->warn_sccipher
= TRUE
;
5142 for (j
= 0; j
< c
->nciphers
; j
++) {
5143 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
5144 s
->sccipher_tobe
= c
->list
[j
];
5149 if (s
->sccipher_tobe
)
5152 if (!s
->sccipher_tobe
) {
5153 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
5154 str ? str
: "(null)"));
5158 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server mac */
5159 for (i
= 0; i
< s
->nmacs
; i
++) {
5160 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5161 s
->csmac_tobe
= s
->maclist
[i
];
5165 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client mac */
5166 for (i
= 0; i
< s
->nmacs
; i
++) {
5167 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5168 s
->scmac_tobe
= s
->maclist
[i
];
5172 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server compression */
5173 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5174 const struct ssh_compress
*c
=
5175 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5176 if (in_commasep_string(c
->name
, str
, len
)) {
5181 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client compression */
5182 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5183 const struct ssh_compress
*c
=
5184 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5185 if (in_commasep_string(c
->name
, str
, len
)) {
5190 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server language */
5191 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client language */
5192 s
->ignorepkt
= ssh2_pkt_getbool(pktin
) && !s
->guessok
;
5195 ssh_set_frozen(ssh
, 1);
5196 s
->dlgret
= askalg(ssh
->frontend
, "key-exchange algorithm",
5198 ssh_dialog_callback
, ssh
);
5199 if (s
->dlgret
< 0) {
5203 bombout(("Unexpected data from server while"
5204 " waiting for user response"));
5207 } while (pktin
|| inlen
> 0);
5208 s
->dlgret
= ssh
->user_response
;
5210 ssh_set_frozen(ssh
, 0);
5211 if (s
->dlgret
== 0) {
5212 ssh
->close_expected
= TRUE
;
5213 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5218 if (s
->warn_cscipher
) {
5219 ssh_set_frozen(ssh
, 1);
5220 s
->dlgret
= askalg(ssh
->frontend
,
5221 "client-to-server cipher",
5222 s
->cscipher_tobe
->name
,
5223 ssh_dialog_callback
, ssh
);
5224 if (s
->dlgret
< 0) {
5228 bombout(("Unexpected data from server while"
5229 " waiting for user response"));
5232 } while (pktin
|| inlen
> 0);
5233 s
->dlgret
= ssh
->user_response
;
5235 ssh_set_frozen(ssh
, 0);
5236 if (s
->dlgret
== 0) {
5237 ssh
->close_expected
= TRUE
;
5238 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5243 if (s
->warn_sccipher
) {
5244 ssh_set_frozen(ssh
, 1);
5245 s
->dlgret
= askalg(ssh
->frontend
,
5246 "server-to-client cipher",
5247 s
->sccipher_tobe
->name
,
5248 ssh_dialog_callback
, ssh
);
5249 if (s
->dlgret
< 0) {
5253 bombout(("Unexpected data from server while"
5254 " waiting for user response"));
5257 } while (pktin
|| inlen
> 0);
5258 s
->dlgret
= ssh
->user_response
;
5260 ssh_set_frozen(ssh
, 0);
5261 if (s
->dlgret
== 0) {
5262 ssh
->close_expected
= TRUE
;
5263 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5268 if (s
->ignorepkt
) /* first_kex_packet_follows */
5269 crWaitUntil(pktin
); /* Ignore packet */
5273 * Work out the number of bits of key we will need from the key
5274 * exchange. We start with the maximum key length of either
5280 csbits
= s
->cscipher_tobe
->keylen
;
5281 scbits
= s
->sccipher_tobe
->keylen
;
5282 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
5284 /* The keys only have 160-bit entropy, since they're based on
5285 * a SHA-1 hash. So cap the key size at 160 bits. */
5290 * If we're doing Diffie-Hellman group exchange, start by
5291 * requesting a group.
5293 if (!ssh
->kex
->pdata
) {
5294 logevent("Doing Diffie-Hellman group exchange");
5295 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
5297 * Work out how big a DH group we will need to allow that
5300 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
5301 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
5302 ssh2_pkt_adduint32(s
->pktout
, s
->pbits
);
5303 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5306 if (pktin
->type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
5307 bombout(("expected key exchange group packet from server"));
5310 s
->p
= ssh2_pkt_getmp(pktin
);
5311 s
->g
= ssh2_pkt_getmp(pktin
);
5312 if (!s
->p
|| !s
->g
) {
5313 bombout(("unable to read mp-ints from incoming group packet"));
5316 ssh
->kex_ctx
= dh_setup_gex(s
->p
, s
->g
);
5317 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
5318 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
5320 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP
;
5321 ssh
->kex_ctx
= dh_setup_group(ssh
->kex
);
5322 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
5323 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
5324 logeventf(ssh
, "Using Diffie-Hellman with standard group \"%s\"",
5325 ssh
->kex
->groupname
);
5328 logevent("Doing Diffie-Hellman key exchange");
5330 * Now generate and send e for Diffie-Hellman.
5332 set_busy_status(ssh
->frontend
, BUSY_CPU
); /* this can take a while */
5333 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
5334 s
->pktout
= ssh2_pkt_init(s
->kex_init_value
);
5335 ssh2_pkt_addmp(s
->pktout
, s
->e
);
5336 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5338 set_busy_status(ssh
->frontend
, BUSY_WAITING
); /* wait for server */
5340 if (pktin
->type
!= s
->kex_reply_value
) {
5341 bombout(("expected key exchange reply packet from server"));
5344 set_busy_status(ssh
->frontend
, BUSY_CPU
); /* cogitate */
5345 ssh_pkt_getstring(pktin
, &s
->hostkeydata
, &s
->hostkeylen
);
5346 s
->f
= ssh2_pkt_getmp(pktin
);
5348 bombout(("unable to parse key exchange reply packet"));
5351 ssh_pkt_getstring(pktin
, &s
->sigdata
, &s
->siglen
);
5353 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
5355 /* We assume everything from now on will be quick, and it might
5356 * involve user interaction. */
5357 set_busy_status(ssh
->frontend
, BUSY_NOT
);
5359 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
5360 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5361 sha_uint32(&ssh
->exhash
, s
->pbits
);
5362 sha_mpint(&ssh
->exhash
, s
->p
);
5363 sha_mpint(&ssh
->exhash
, s
->g
);
5365 sha_mpint(&ssh
->exhash
, s
->e
);
5366 sha_mpint(&ssh
->exhash
, s
->f
);
5367 sha_mpint(&ssh
->exhash
, s
->K
);
5368 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
5370 dh_cleanup(ssh
->kex_ctx
);
5371 ssh
->kex_ctx
= NULL
;
5374 debug(("Exchange hash is:\n"));
5375 dmemdump(s
->exchange_hash
, 20);
5378 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
5380 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
5381 (char *)s
->exchange_hash
, 20)) {
5382 bombout(("Server's host key did not match the signature supplied"));
5387 * Authenticate remote host: verify host key. (We've already
5388 * checked the signature of the exchange hash.)
5390 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
5391 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
5392 ssh_set_frozen(ssh
, 1);
5393 s
->dlgret
= verify_ssh_host_key(ssh
->frontend
,
5394 ssh
->savedhost
, ssh
->savedport
,
5395 ssh
->hostkey
->keytype
, s
->keystr
,
5397 ssh_dialog_callback
, ssh
);
5398 if (s
->dlgret
< 0) {
5402 bombout(("Unexpected data from server while waiting"
5403 " for user host key response"));
5406 } while (pktin
|| inlen
> 0);
5407 s
->dlgret
= ssh
->user_response
;
5409 ssh_set_frozen(ssh
, 0);
5410 if (s
->dlgret
== 0) {
5411 ssh
->close_expected
= TRUE
;
5412 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5415 if (!s
->got_session_id
) { /* don't bother logging this in rekeys */
5416 logevent("Host key fingerprint is:");
5417 logevent(s
->fingerprint
);
5419 sfree(s
->fingerprint
);
5421 ssh
->hostkey
->freekey(s
->hkey
);
5424 * The exchange hash from the very first key exchange is also
5425 * the session id, used in session key construction and
5428 if (!s
->got_session_id
) {
5429 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
5430 sizeof(s
->exchange_hash
));
5431 s
->got_session_id
= TRUE
;
5435 * Send SSH2_MSG_NEWKEYS.
5437 s
->pktout
= ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
5438 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5439 ssh
->outgoing_data_size
= 0; /* start counting from here */
5442 * We've sent client NEWKEYS, so create and initialise
5443 * client-to-server session keys.
5445 if (ssh
->cs_cipher_ctx
)
5446 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
5447 ssh
->cscipher
= s
->cscipher_tobe
;
5448 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
5450 if (ssh
->cs_mac_ctx
)
5451 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
5452 ssh
->csmac
= s
->csmac_tobe
;
5453 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
5455 if (ssh
->cs_comp_ctx
)
5456 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
5457 ssh
->cscomp
= s
->cscomp_tobe
;
5458 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
5461 * Set IVs on client-to-server keys. Here we use the exchange
5462 * hash from the _first_ key exchange.
5465 unsigned char keyspace
[40];
5466 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
5467 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
5468 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
5469 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
5470 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
5471 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
5474 logeventf(ssh
, "Initialised %.200s client->server encryption",
5475 ssh
->cscipher
->text_name
);
5476 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
5477 ssh
->csmac
->text_name
);
5478 if (ssh
->cscomp
->text_name
)
5479 logeventf(ssh
, "Initialised %s compression",
5480 ssh
->cscomp
->text_name
);
5483 * Now our end of the key exchange is complete, we can send all
5484 * our queued higher-layer packets.
5486 ssh
->queueing
= FALSE
;
5487 ssh2_pkt_queuesend(ssh
);
5490 * Expect SSH2_MSG_NEWKEYS from server.
5493 if (pktin
->type
!= SSH2_MSG_NEWKEYS
) {
5494 bombout(("expected new-keys packet from server"));
5497 ssh
->incoming_data_size
= 0; /* start counting from here */
5500 * We've seen server NEWKEYS, so create and initialise
5501 * server-to-client session keys.
5503 if (ssh
->sc_cipher_ctx
)
5504 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
5505 ssh
->sccipher
= s
->sccipher_tobe
;
5506 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
5508 if (ssh
->sc_mac_ctx
)
5509 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
5510 ssh
->scmac
= s
->scmac_tobe
;
5511 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
5513 if (ssh
->sc_comp_ctx
)
5514 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
5515 ssh
->sccomp
= s
->sccomp_tobe
;
5516 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
5519 * Set IVs on server-to-client keys. Here we use the exchange
5520 * hash from the _first_ key exchange.
5523 unsigned char keyspace
[40];
5524 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
5525 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
5526 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
5527 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
5528 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
5529 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
5531 logeventf(ssh
, "Initialised %.200s server->client encryption",
5532 ssh
->sccipher
->text_name
);
5533 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
5534 ssh
->scmac
->text_name
);
5535 if (ssh
->sccomp
->text_name
)
5536 logeventf(ssh
, "Initialised %s decompression",
5537 ssh
->sccomp
->text_name
);
5540 * Free key exchange data.
5544 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5550 * Key exchange is over. Loop straight back round if we have a
5551 * deferred rekey reason.
5553 if (ssh
->deferred_rekey_reason
) {
5554 logevent(ssh
->deferred_rekey_reason
);
5556 ssh
->deferred_rekey_reason
= NULL
;
5557 goto begin_key_exchange
;
5561 * Otherwise, schedule a timer for our next rekey.
5563 ssh
->kex_in_progress
= FALSE
;
5564 ssh
->last_rekey
= GETTICKCOUNT();
5565 if (ssh
->cfg
.ssh_rekey_time
!= 0)
5566 ssh
->next_rekey
= schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5570 * If this is the first key exchange phase, we must pass the
5571 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5572 * wants to see it but because it will need time to initialise
5573 * itself before it sees an actual packet. In subsequent key
5574 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5575 * it would only confuse the layer above.
5577 if (s
->activated_authconn
) {
5580 s
->activated_authconn
= TRUE
;
5583 * Now we're encrypting. Begin returning 1 to the protocol main
5584 * function so that other things can run on top of the
5585 * transport. If we ever see a KEXINIT, we must go back to the
5588 * We _also_ go back to the start if we see pktin==NULL and
5589 * inlen==-1, because this is a special signal meaning
5590 * `initiate client-driven rekey', and `in' contains a message
5591 * giving the reason for the rekey.
5593 while (!((pktin
&& pktin
->type
== SSH2_MSG_KEXINIT
) ||
5594 (!pktin
&& inlen
== -1))) {
5599 logevent("Server initiated key re-exchange");
5602 * Special case: if the server bug is set that doesn't
5603 * allow rekeying, we give a different log message and
5604 * continue waiting. (If such a server _initiates_ a rekey,
5605 * we process it anyway!)
5607 if ((ssh
->remote_bugs
& BUG_SSH2_REKEY
)) {
5608 logeventf(ssh
, "Server bug prevents key re-exchange (%s)",
5610 /* Reset the counters, so that at least this message doesn't
5611 * hit the event log _too_ often. */
5612 ssh
->outgoing_data_size
= 0;
5613 ssh
->incoming_data_size
= 0;
5614 if (ssh
->cfg
.ssh_rekey_time
!= 0) {
5616 schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5619 goto wait_for_rekey
; /* this is utterly horrid */
5621 logeventf(ssh
, "Initiating key re-exchange (%s)", (char *)in
);
5624 goto begin_key_exchange
;
5630 * Add data to an SSH-2 channel output buffer.
5632 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
5635 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
5639 * Attempt to send data on an SSH-2 channel.
5641 static int ssh2_try_send(struct ssh_channel
*c
)
5644 struct Packet
*pktout
;
5646 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
5649 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
5650 if ((unsigned)len
> c
->v
.v2
.remwindow
)
5651 len
= c
->v
.v2
.remwindow
;
5652 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
5653 len
= c
->v
.v2
.remmaxpkt
;
5654 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
5655 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5656 dont_log_data(ssh
, pktout
, PKTLOG_OMIT
);
5657 ssh2_pkt_addstring_start(pktout
);
5658 ssh2_pkt_addstring_data(pktout
, data
, len
);
5659 end_log_omission(ssh
, pktout
);
5660 ssh2_pkt_send(ssh
, pktout
);
5661 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
5662 c
->v
.v2
.remwindow
-= len
;
5666 * After having sent as much data as we can, return the amount
5669 return bufchain_size(&c
->v
.v2
.outbuffer
);
5672 static void ssh2_try_send_and_unthrottle(struct ssh_channel
*c
)
5676 return; /* don't send on closing channels */
5677 bufsize
= ssh2_try_send(c
);
5680 case CHAN_MAINSESSION
:
5681 /* stdin need not receive an unthrottle
5682 * notification since it will be polled */
5685 x11_unthrottle(c
->u
.x11
.s
);
5688 /* agent sockets are request/response and need no
5689 * buffer management */
5692 pfd_unthrottle(c
->u
.pfd
.s
);
5699 * Potentially enlarge the window on an SSH-2 channel.
5701 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
5706 * Never send WINDOW_ADJUST for a channel that the remote side
5707 * already thinks it's closed; there's no point, since it won't
5708 * be sending any more data anyway.
5714 * Only send a WINDOW_ADJUST if there's significantly more window
5715 * available than the other end thinks there is. This saves us
5716 * sending a WINDOW_ADJUST for every character in a shell session.
5718 * "Significant" is arbitrarily defined as half the window size.
5720 if (newwin
> c
->v
.v2
.locwindow
* 2) {
5721 struct Packet
*pktout
;
5723 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5724 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5725 ssh2_pkt_adduint32(pktout
, newwin
- c
->v
.v2
.locwindow
);
5726 ssh2_pkt_send(ssh
, pktout
);
5727 c
->v
.v2
.locwindow
= newwin
;
5731 static void ssh2_msg_channel_window_adjust(Ssh ssh
, struct Packet
*pktin
)
5733 unsigned i
= ssh_pkt_getuint32(pktin
);
5734 struct ssh_channel
*c
;
5735 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5736 if (c
&& !c
->closes
) {
5737 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
5738 ssh2_try_send_and_unthrottle(c
);
5742 static void ssh2_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
5746 unsigned i
= ssh_pkt_getuint32(pktin
);
5747 struct ssh_channel
*c
;
5748 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5750 return; /* nonexistent channel */
5751 if (pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5752 ssh_pkt_getuint32(pktin
) != SSH2_EXTENDED_DATA_STDERR
)
5753 return; /* extended but not stderr */
5754 ssh_pkt_getstring(pktin
, &data
, &length
);
5757 c
->v
.v2
.locwindow
-= length
;
5759 case CHAN_MAINSESSION
:
5761 from_backend(ssh
->frontend
, pktin
->type
==
5762 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5766 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5769 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5772 while (length
> 0) {
5773 if (c
->u
.a
.lensofar
< 4) {
5774 unsigned int l
= min(4 - c
->u
.a
.lensofar
, length
);
5775 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5779 c
->u
.a
.lensofar
+= l
;
5781 if (c
->u
.a
.lensofar
== 4) {
5783 4 + GET_32BIT(c
->u
.a
.msglen
);
5784 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
5786 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5788 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5790 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5792 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5796 c
->u
.a
.lensofar
+= l
;
5798 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5801 if (agent_query(c
->u
.a
.message
,
5804 ssh_agentf_callback
, c
))
5805 ssh_agentf_callback(c
, reply
, replylen
);
5806 sfree(c
->u
.a
.message
);
5807 c
->u
.a
.lensofar
= 0;
5814 * If we are not buffering too much data,
5815 * enlarge the window again at the remote side.
5817 if (bufsize
< OUR_V2_WINSIZE
)
5818 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5822 static void ssh2_msg_channel_eof(Ssh ssh
, struct Packet
*pktin
)
5824 unsigned i
= ssh_pkt_getuint32(pktin
);
5825 struct ssh_channel
*c
;
5827 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5829 return; /* nonexistent channel */
5831 if (c
->type
== CHAN_X11
) {
5833 * Remote EOF on an X11 channel means we should
5834 * wrap up and close the channel ourselves.
5836 x11_close(c
->u
.x11
.s
);
5838 } else if (c
->type
== CHAN_AGENT
) {
5840 } else if (c
->type
== CHAN_SOCKDATA
) {
5841 pfd_close(c
->u
.pfd
.s
);
5846 static void ssh2_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
5848 unsigned i
= ssh_pkt_getuint32(pktin
);
5849 struct ssh_channel
*c
;
5850 struct Packet
*pktout
;
5852 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5853 if (!c
|| c
->halfopen
) {
5854 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5855 c ?
"half-open" : "nonexistent", i
));
5858 /* Do pre-close processing on the channel. */
5860 case CHAN_MAINSESSION
:
5861 ssh
->mainchan
= NULL
;
5862 update_specials_menu(ssh
->frontend
);
5865 if (c
->u
.x11
.s
!= NULL
)
5866 x11_close(c
->u
.x11
.s
);
5873 if (c
->u
.pfd
.s
!= NULL
)
5874 pfd_close(c
->u
.pfd
.s
);
5878 if (c
->closes
== 0) {
5879 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5880 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5881 ssh2_pkt_send(ssh
, pktout
);
5883 del234(ssh
->channels
, c
);
5884 bufchain_clear(&c
->v
.v2
.outbuffer
);
5888 * See if that was the last channel left open.
5889 * (This is only our termination condition if we're
5890 * not running in -N mode.)
5892 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
5893 logevent("All channels closed. Disconnecting");
5896 * We used to send SSH_MSG_DISCONNECT here,
5897 * because I'd believed that _every_ conforming
5898 * SSH-2 connection had to end with a disconnect
5899 * being sent by at least one side; apparently
5900 * I was wrong and it's perfectly OK to
5901 * unceremoniously slam the connection shut
5902 * when you're done, and indeed OpenSSH feels
5903 * this is more polite than sending a
5904 * DISCONNECT. So now we don't.
5906 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5907 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5908 ssh2_pkt_addstring(s
->pktout
, "All open channels closed");
5909 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
5910 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5912 ssh
->close_expected
= TRUE
;
5913 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5917 static void ssh2_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
5919 unsigned i
= ssh_pkt_getuint32(pktin
);
5920 struct ssh_channel
*c
;
5921 struct Packet
*pktout
;
5923 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5925 return; /* nonexistent channel */
5926 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5927 return; /* dunno why they're confirming this */
5928 c
->remoteid
= ssh_pkt_getuint32(pktin
);
5929 c
->halfopen
= FALSE
;
5930 c
->type
= CHAN_SOCKDATA
;
5931 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
5932 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
5934 pfd_confirm(c
->u
.pfd
.s
);
5937 * We have a pending close on this channel,
5938 * which we decided on before the server acked
5939 * the channel open. So now we know the
5940 * remoteid, we can close it again.
5942 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5943 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5944 ssh2_pkt_send(ssh
, pktout
);
5948 static void ssh2_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
5950 static const char *const reasons
[] = {
5951 "<unknown reason code>",
5952 "Administratively prohibited",
5954 "Unknown channel type",
5955 "Resource shortage",
5957 unsigned i
= ssh_pkt_getuint32(pktin
);
5958 unsigned reason_code
;
5959 char *reason_string
;
5961 struct ssh_channel
*c
;
5962 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5964 return; /* nonexistent channel */
5965 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5966 return; /* dunno why they're failing this */
5968 reason_code
= ssh_pkt_getuint32(pktin
);
5969 if (reason_code
>= lenof(reasons
))
5970 reason_code
= 0; /* ensure reasons[reason_code] in range */
5971 ssh_pkt_getstring(pktin
, &reason_string
, &reason_length
);
5972 logeventf(ssh
, "Forwarded connection refused by server: %s [%.*s]",
5973 reasons
[reason_code
], reason_length
, reason_string
);
5975 pfd_close(c
->u
.pfd
.s
);
5977 del234(ssh
->channels
, c
);
5981 static void ssh2_msg_channel_request(Ssh ssh
, struct Packet
*pktin
)
5985 int typelen
, want_reply
;
5986 int reply
= SSH2_MSG_CHANNEL_FAILURE
; /* default */
5987 struct ssh_channel
*c
;
5988 struct Packet
*pktout
;
5990 localid
= ssh_pkt_getuint32(pktin
);
5991 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5992 want_reply
= ssh2_pkt_getbool(pktin
);
5995 * First, check that the channel exists. Otherwise,
5996 * we can instantly disconnect with a rude message.
5998 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
6001 sprintf(buf
, "Received channel request for nonexistent"
6002 " channel %d", localid
);
6004 pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6005 ssh2_pkt_adduint32(pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
6006 ssh2_pkt_addstring(pktout
, buf
);
6007 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
6008 ssh2_pkt_send_noqueue(ssh
, pktout
);
6009 connection_fatal(ssh
->frontend
, "%s", buf
);
6010 ssh
->close_expected
= TRUE
;
6011 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6016 * Having got the channel number, we now look at
6017 * the request type string to see if it's something
6020 if (c
== ssh
->mainchan
) {
6022 * We recognise "exit-status" and "exit-signal" on
6023 * the primary channel.
6025 if (typelen
== 11 &&
6026 !memcmp(type
, "exit-status", 11)) {
6028 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
6029 logeventf(ssh
, "Server sent command exit status %d",
6031 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
6033 } else if (typelen
== 11 &&
6034 !memcmp(type
, "exit-signal", 11)) {
6036 int is_plausible
= TRUE
, is_int
= FALSE
;
6037 char *fmt_sig
= "", *fmt_msg
= "";
6039 int msglen
= 0, core
= FALSE
;
6040 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
6041 * provide an `int' for the signal, despite its
6042 * having been a `string' in the drafts since at
6043 * least 2001. (Fixed in session.c 1.147.) Try to
6044 * infer which we can safely parse it as. */
6046 unsigned char *p
= pktin
->body
+
6048 long len
= pktin
->length
- pktin
->savedpos
;
6049 unsigned long num
= GET_32BIT(p
); /* what is it? */
6050 /* If it's 0, it hardly matters; assume string */
6054 int maybe_int
= FALSE
, maybe_str
= FALSE
;
6055 #define CHECK_HYPOTHESIS(offset, result) \
6058 if (q >= 0 && q+4 <= len) { \
6059 q = q + 4 + GET_32BIT(p+q); \
6060 if (q >= 0 && q+4 <= len && \
6061 ((q = q + 4 + GET_32BIT(p+q))!= 0) && q == len) \
6065 CHECK_HYPOTHESIS(4+1, maybe_int
);
6066 CHECK_HYPOTHESIS(4+num
+1, maybe_str
);
6067 #undef CHECK_HYPOTHESIS
6068 if (maybe_int
&& !maybe_str
)
6070 else if (!maybe_int
&& maybe_str
)
6073 /* Crikey. Either or neither. Panic. */
6074 is_plausible
= FALSE
;
6079 /* Old non-standard OpenSSH. */
6080 int signum
= ssh_pkt_getuint32(pktin
);
6081 fmt_sig
= dupprintf(" %d", signum
);
6083 /* As per the drafts. */
6086 ssh_pkt_getstring(pktin
, &sig
, &siglen
);
6087 /* Signal name isn't supposed to be blank, but
6088 * let's cope gracefully if it is. */
6090 fmt_sig
= dupprintf(" \"%.*s\"",
6094 core
= ssh2_pkt_getbool(pktin
);
6095 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
6097 fmt_msg
= dupprintf(" (\"%.*s\")", msglen
, msg
);
6099 /* ignore lang tag */
6100 } /* else don't attempt to parse */
6101 logeventf(ssh
, "Server exited on signal%s%s%s",
6102 fmt_sig
, core ?
" (core dumped)" : "",
6104 if (*fmt_sig
) sfree(fmt_sig
);
6105 if (*fmt_msg
) sfree(fmt_msg
);
6106 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
6111 * This is a channel request we don't know
6112 * about, so we now either ignore the request
6113 * or respond with CHANNEL_FAILURE, depending
6116 reply
= SSH2_MSG_CHANNEL_FAILURE
;
6119 pktout
= ssh2_pkt_init(reply
);
6120 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6121 ssh2_pkt_send(ssh
, pktout
);
6125 static void ssh2_msg_global_request(Ssh ssh
, struct Packet
*pktin
)
6128 int typelen
, want_reply
;
6129 struct Packet
*pktout
;
6131 ssh_pkt_getstring(pktin
, &type
, &typelen
);
6132 want_reply
= ssh2_pkt_getbool(pktin
);
6135 * We currently don't support any global requests
6136 * at all, so we either ignore the request or
6137 * respond with REQUEST_FAILURE, depending on
6141 pktout
= ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
6142 ssh2_pkt_send(ssh
, pktout
);
6146 static void ssh2_msg_channel_open(Ssh ssh
, struct Packet
*pktin
)
6154 struct ssh_channel
*c
;
6155 unsigned remid
, winsize
, pktsize
;
6156 struct Packet
*pktout
;
6158 ssh_pkt_getstring(pktin
, &type
, &typelen
);
6159 c
= snew(struct ssh_channel
);
6162 remid
= ssh_pkt_getuint32(pktin
);
6163 winsize
= ssh_pkt_getuint32(pktin
);
6164 pktsize
= ssh_pkt_getuint32(pktin
);
6166 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
6169 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
6170 addrstr
= snewn(peeraddrlen
+1, char);
6171 memcpy(addrstr
, peeraddr
, peeraddrlen
);
6172 addrstr
[peeraddrlen
] = '\0';
6173 peerport
= ssh_pkt_getuint32(pktin
);
6175 logeventf(ssh
, "Received X11 connect request from %s:%d",
6178 if (!ssh
->X11_fwd_enabled
)
6179 error
= "X11 forwarding is not enabled";
6180 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
6181 ssh
->x11auth
, addrstr
, peerport
,
6182 &ssh
->cfg
) != NULL
) {
6183 error
= "Unable to open an X11 connection";
6185 logevent("Opening X11 forward connection succeeded");
6190 } else if (typelen
== 15 &&
6191 !memcmp(type
, "forwarded-tcpip", 15)) {
6192 struct ssh_rportfwd pf
, *realpf
;
6195 ssh_pkt_getstring(pktin
, &dummy
, &dummylen
);/* skip address */
6196 pf
.sport
= ssh_pkt_getuint32(pktin
);
6197 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
6198 peerport
= ssh_pkt_getuint32(pktin
);
6199 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
6200 logeventf(ssh
, "Received remote port %d open request "
6201 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
6202 if (realpf
== NULL
) {
6203 error
= "Remote port is not recognised";
6205 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
6209 realpf
->pfrec
->addressfamily
);
6210 logeventf(ssh
, "Attempting to forward remote port to "
6211 "%s:%d", realpf
->dhost
, realpf
->dport
);
6213 logeventf(ssh
, "Port open failed: %s", e
);
6214 error
= "Port open failed";
6216 logevent("Forwarded port opened successfully");
6217 c
->type
= CHAN_SOCKDATA
;
6220 } else if (typelen
== 22 &&
6221 !memcmp(type
, "auth-agent@openssh.com", 3)) {
6222 if (!ssh
->agentfwd_enabled
)
6223 error
= "Agent forwarding is not enabled";
6225 c
->type
= CHAN_AGENT
; /* identify channel type */
6226 c
->u
.a
.lensofar
= 0;
6229 error
= "Unsupported channel type requested";
6232 c
->remoteid
= remid
;
6233 c
->halfopen
= FALSE
;
6235 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
6236 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6237 ssh2_pkt_adduint32(pktout
, SSH2_OPEN_CONNECT_FAILED
);
6238 ssh2_pkt_addstring(pktout
, error
);
6239 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
6240 ssh2_pkt_send(ssh
, pktout
);
6241 logeventf(ssh
, "Rejected channel open: %s", error
);
6244 c
->localid
= alloc_channel_id(ssh
);
6246 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6247 c
->v
.v2
.remwindow
= winsize
;
6248 c
->v
.v2
.remmaxpkt
= pktsize
;
6249 bufchain_init(&c
->v
.v2
.outbuffer
);
6250 add234(ssh
->channels
, c
);
6251 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
6252 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6253 ssh2_pkt_adduint32(pktout
, c
->localid
);
6254 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);
6255 ssh2_pkt_adduint32(pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
6256 ssh2_pkt_send(ssh
, pktout
);
6261 * Handle the SSH-2 userauth and connection layers.
6263 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
6264 struct Packet
*pktin
)
6266 struct do_ssh2_authconn_state
{
6268 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
6270 AUTH_KEYBOARD_INTERACTIVE
6274 AUTH_TYPE_PUBLICKEY
,
6275 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
6276 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
6278 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
6279 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
6281 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
6282 int tried_pubkey_config
, tried_agent
;
6283 int kbd_inter_running
, kbd_inter_refused
;
6285 int num_prompts
, curr_prompt
, echo
;
6290 void *publickey_blob
;
6291 int publickey_bloblen
;
6292 unsigned char request
[5], *response
, *p
;
6296 char *pkblob
, *alg
, *commentp
;
6297 int pklen
, alglen
, commentlen
;
6298 int siglen
, retlen
, len
;
6299 char *q
, *agentreq
, *ret
;
6301 int num_env
, env_left
, env_ok
;
6302 struct Packet
*pktout
;
6304 crState(do_ssh2_authconn_state
);
6306 crBegin(ssh
->do_ssh2_authconn_crstate
);
6309 * Request userauth protocol, and await a response to it.
6311 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
6312 ssh2_pkt_addstring(s
->pktout
, "ssh-userauth");
6313 ssh2_pkt_send(ssh
, s
->pktout
);
6314 crWaitUntilV(pktin
);
6315 if (pktin
->type
!= SSH2_MSG_SERVICE_ACCEPT
) {
6316 bombout(("Server refused user authentication protocol"));
6321 * We repeat this whole loop, including the username prompt,
6322 * until we manage a successful authentication. If the user
6323 * types the wrong _password_, they can be sent back to the
6324 * beginning to try another username, if this is configured on.
6325 * (If they specify a username in the config, they are never
6326 * asked, even if they do give a wrong password.)
6328 * I think this best serves the needs of
6330 * - the people who have no configuration, no keys, and just
6331 * want to try repeated (username,password) pairs until they
6332 * type both correctly
6334 * - people who have keys and configuration but occasionally
6335 * need to fall back to passwords
6337 * - people with a key held in Pageant, who might not have
6338 * logged in to a particular machine before; so they want to
6339 * type a username, and then _either_ their key will be
6340 * accepted, _or_ they will type a password. If they mistype
6341 * the username they will want to be able to get back and
6344 s
->username
[0] = '\0';
6345 s
->got_username
= FALSE
;
6350 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
6352 * We got a username last time round this loop, and
6353 * with change_username turned off we don't try to get
6356 } else if (!*ssh
->cfg
.username
) {
6357 if (ssh_get_line
&& !ssh_getline_pw_only
) {
6358 if (!ssh_get_line("login as: ",
6359 s
->username
, sizeof(s
->username
), FALSE
)) {
6361 * get_line failed to get a username.
6364 logevent("No username provided. Abandoning session.");
6365 ssh
->close_expected
= TRUE
;
6366 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6370 int ret
; /* need not be saved across crReturn */
6371 c_write_str(ssh
, "login as: ");
6373 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
6375 crWaitUntilV(!pktin
);
6376 ret
= process_userpass_input(ssh
, in
, inlen
);
6380 c_write_str(ssh
, "\r\n");
6382 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
6385 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
6386 s
->username
[sizeof(s
->username
)-1] = '\0';
6387 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
6388 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
6389 c_write_str(ssh
, stuff
);
6393 s
->got_username
= TRUE
;
6396 * Send an authentication request using method "none": (a)
6397 * just in case it succeeds, and (b) so that we know what
6398 * authentication methods we can usefully try next.
6400 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6402 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6403 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6404 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");/* service requested */
6405 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6406 ssh2_pkt_send(ssh
, s
->pktout
);
6407 s
->type
= AUTH_TYPE_NONE
;
6409 s
->we_are_in
= FALSE
;
6411 s
->tried_pubkey_config
= FALSE
;
6412 s
->tried_agent
= FALSE
;
6413 s
->kbd_inter_running
= FALSE
;
6414 s
->kbd_inter_refused
= FALSE
;
6415 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
6416 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
6418 logeventf(ssh
, "Reading private key file \"%.150s\"",
6419 filename_to_str(&ssh
->cfg
.keyfile
));
6420 keytype
= key_type(&ssh
->cfg
.keyfile
);
6421 if (keytype
== SSH_KEYTYPE_SSH2
) {
6423 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
6424 &s
->publickey_bloblen
, NULL
);
6427 logeventf(ssh
, "Unable to use this key file (%s)",
6428 key_type_to_str(keytype
));
6429 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
6431 filename_to_str(&ssh
->cfg
.keyfile
),
6432 key_type_to_str(keytype
));
6433 c_write_str(ssh
, msgbuf
);
6435 s
->publickey_blob
= NULL
;
6438 s
->publickey_blob
= NULL
;
6442 * Wait for the result of the last authentication request.
6445 crWaitUntilV(pktin
);
6446 while (pktin
->type
== SSH2_MSG_USERAUTH_BANNER
) {
6450 * Don't show the banner if we're operating in
6451 * non-verbose non-interactive mode. (It's probably
6452 * a script, which means nobody will read the
6453 * banner _anyway_, and moreover the printing of
6454 * the banner will screw up processing on the
6455 * output of (say) plink.)
6457 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
6458 ssh_pkt_getstring(pktin
, &banner
, &size
);
6460 c_write_untrusted(ssh
, banner
, size
);
6462 crWaitUntilV(pktin
);
6464 if (pktin
->type
== SSH2_MSG_USERAUTH_SUCCESS
) {
6465 logevent("Access granted");
6466 s
->we_are_in
= TRUE
;
6470 if (s
->kbd_inter_running
&&
6471 pktin
->type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6473 * This is either a further set-of-prompts packet
6474 * in keyboard-interactive authentication, or it's
6475 * the same one and we came back here with `gotit'
6476 * set. In the former case, we must reset the
6477 * curr_prompt variable.
6481 } else if (pktin
->type
== SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
) {
6482 /* FIXME: perhaps we should support this? */
6483 bombout(("PASSWD_CHANGEREQ not yet supported"));
6485 } else if (pktin
->type
!= SSH2_MSG_USERAUTH_FAILURE
) {
6486 bombout(("Strange packet received during authentication: type %d",
6494 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6495 * we can look at the string in it and know what we can
6496 * helpfully try next.
6498 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
) {
6501 ssh_pkt_getstring(pktin
, &methods
, &methlen
);
6502 s
->kbd_inter_running
= FALSE
;
6503 if (!ssh2_pkt_getbool(pktin
)) {
6505 * We have received an unequivocal Access
6506 * Denied. This can translate to a variety of
6509 * - if we'd just tried "none" authentication,
6510 * it's not worth printing anything at all
6512 * - if we'd just tried a public key _offer_,
6513 * the message should be "Server refused our
6514 * key" (or no message at all if the key
6515 * came from Pageant)
6517 * - if we'd just tried anything else, the
6518 * message really should be "Access denied".
6520 * Additionally, if we'd just tried password
6521 * authentication, we should break out of this
6522 * whole loop so as to go back to the username
6523 * prompt (iff we're configured to allow
6524 * username change attempts).
6526 if (s
->type
== AUTH_TYPE_NONE
) {
6528 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
6529 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
6530 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
6531 c_write_str(ssh
, "Server refused our key\r\n");
6532 logevent("Server refused public key");
6533 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
6534 /* server declined keyboard-interactive; ignore */
6536 c_write_str(ssh
, "Access denied\r\n");
6537 logevent("Access denied");
6538 if (s
->type
== AUTH_TYPE_PASSWORD
&&
6539 ssh
->cfg
.change_username
) {
6540 /* XXX perhaps we should allow
6541 * keyboard-interactive to do this too? */
6542 s
->we_are_in
= FALSE
;
6547 c_write_str(ssh
, "Further authentication required\r\n");
6548 logevent("Further authentication required");
6552 in_commasep_string("publickey", methods
, methlen
);
6554 in_commasep_string("password", methods
, methlen
);
6555 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
6556 in_commasep_string("keyboard-interactive", methods
, methlen
);
6560 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6564 * Most password/passphrase prompts will be
6565 * non-echoing, so we set this to 0 by default.
6566 * Exception is that some keyboard-interactive prompts
6567 * can be echoing, in which case we'll set this to 1.
6571 if (!s
->method
&& s
->can_pubkey
&&
6572 agent_exists() && !s
->tried_agent
) {
6574 * Attempt public-key authentication using Pageant.
6579 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6580 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6582 s
->tried_agent
= TRUE
;
6584 logevent("Pageant is running. Requesting keys.");
6586 /* Request the keys held by the agent. */
6587 PUT_32BIT(s
->request
, 1);
6588 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
6589 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
6590 ssh_agent_callback
, ssh
)) {
6594 bombout(("Unexpected data from server while"
6595 " waiting for agent response"));
6598 } while (pktin
|| inlen
> 0);
6599 r
= ssh
->agent_response
;
6600 s
->responselen
= ssh
->agent_response_len
;
6602 s
->response
= (unsigned char *) r
;
6603 if (s
->response
&& s
->responselen
>= 5 &&
6604 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
6605 s
->p
= s
->response
+ 5;
6606 s
->nkeys
= GET_32BIT(s
->p
);
6608 logeventf(ssh
, "Pageant has %d SSH-2 keys", s
->nkeys
);
6609 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
6612 logeventf(ssh
, "Trying Pageant key #%d", s
->keyi
);
6613 s
->pklen
= GET_32BIT(s
->p
);
6615 if (s
->publickey_blob
&&
6616 s
->pklen
== s
->publickey_bloblen
&&
6617 !memcmp(s
->p
, s
->publickey_blob
,
6618 s
->publickey_bloblen
)) {
6619 logevent("This key matches configured key file");
6620 s
->tried_pubkey_config
= 1;
6622 s
->pkblob
= (char *)s
->p
;
6624 s
->alglen
= GET_32BIT(s
->pkblob
);
6625 s
->alg
= s
->pkblob
+ 4;
6626 s
->commentlen
= GET_32BIT(s
->p
);
6628 s
->commentp
= (char *)s
->p
;
6629 s
->p
+= s
->commentlen
;
6630 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6631 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6632 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6633 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6634 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6635 ssh2_pkt_addstring_start(s
->pktout
);
6636 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6637 ssh2_pkt_addstring_start(s
->pktout
);
6638 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6639 ssh2_pkt_send(ssh
, s
->pktout
);
6641 crWaitUntilV(pktin
);
6642 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6643 logevent("Key refused");
6647 if (flags
& FLAG_VERBOSE
) {
6648 c_write_str(ssh
, "Authenticating with "
6650 c_write(ssh
, s
->commentp
, s
->commentlen
);
6651 c_write_str(ssh
, "\" from agent\r\n");
6655 * Server is willing to accept the key.
6656 * Construct a SIGN_REQUEST.
6658 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6659 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6660 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6661 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6662 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6663 ssh2_pkt_addstring_start(s
->pktout
);
6664 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6665 ssh2_pkt_addstring_start(s
->pktout
);
6666 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6668 s
->siglen
= s
->pktout
->length
- 5 + 4 + 20;
6669 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6671 s
->len
= 1; /* message type */
6672 s
->len
+= 4 + s
->pklen
; /* key blob */
6673 s
->len
+= 4 + s
->siglen
; /* data to sign */
6674 s
->len
+= 4; /* flags */
6675 s
->agentreq
= snewn(4 + s
->len
, char);
6676 PUT_32BIT(s
->agentreq
, s
->len
);
6677 s
->q
= s
->agentreq
+ 4;
6678 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
6679 PUT_32BIT(s
->q
, s
->pklen
);
6681 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
6683 PUT_32BIT(s
->q
, s
->siglen
);
6685 /* Now the data to be signed... */
6686 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6687 PUT_32BIT(s
->q
, 20);
6690 memcpy(s
->q
, ssh
->v2_session_id
, 20);
6692 memcpy(s
->q
, s
->pktout
->data
+ 5,
6693 s
->pktout
->length
- 5);
6694 s
->q
+= s
->pktout
->length
- 5;
6695 /* And finally the (zero) flags word. */
6697 if (!agent_query(s
->agentreq
, s
->len
+ 4,
6699 ssh_agent_callback
, ssh
)) {
6703 bombout(("Unexpected data from server"
6704 " while waiting for agent"
6708 } while (pktin
|| inlen
> 0);
6709 vret
= ssh
->agent_response
;
6710 s
->retlen
= ssh
->agent_response_len
;
6715 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
6716 logevent("Sending Pageant's response");
6717 ssh2_add_sigblob(ssh
, s
->pktout
,
6718 s
->pkblob
, s
->pklen
,
6720 GET_32BIT(s
->ret
+ 5));
6721 ssh2_pkt_send(ssh
, s
->pktout
);
6726 ("Pageant failed to answer challenge");
6737 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
6738 && !s
->tried_pubkey_config
) {
6739 unsigned char *pub_blob
;
6740 char *algorithm
, *comment
;
6743 s
->tried_pubkey_config
= TRUE
;
6745 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6746 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6749 * Try the public key supplied in the configuration.
6751 * First, offer the public blob to see if the server is
6752 * willing to accept it.
6755 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
6760 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6761 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6762 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6763 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6764 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6765 ssh2_pkt_addstring(s
->pktout
, algorithm
);
6766 ssh2_pkt_addstring_start(s
->pktout
);
6767 ssh2_pkt_addstring_data(s
->pktout
, (char *)pub_blob
,
6769 ssh2_pkt_send(ssh
, s
->pktout
);
6770 logevent("Offered public key");
6772 crWaitUntilV(pktin
);
6773 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6775 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
6776 continue; /* key refused; give up on it */
6779 logevent("Offer of public key accepted");
6781 * Actually attempt a serious authentication using
6784 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
6785 sprintf(s
->pwprompt
,
6786 "Passphrase for key \"%.100s\": ",
6792 if (flags
& FLAG_VERBOSE
) {
6793 c_write_str(ssh
, "Authenticating with public key \"");
6794 c_write_str(ssh
, comment
);
6795 c_write_str(ssh
, "\"\r\n");
6797 s
->method
= AUTH_PUBLICKEY_FILE
;
6801 if (!s
->method
&& s
->can_keyb_inter
&& !s
->kbd_inter_refused
&&
6802 !s
->kbd_inter_running
) {
6803 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6804 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6806 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6807 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6809 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6810 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6811 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6812 ssh2_pkt_addstring(s
->pktout
, "keyboard-interactive"); /* method */
6813 ssh2_pkt_addstring(s
->pktout
, ""); /* lang */
6814 ssh2_pkt_addstring(s
->pktout
, "");
6815 ssh2_pkt_send(ssh
, s
->pktout
);
6817 crWaitUntilV(pktin
);
6818 if (pktin
->type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6819 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
)
6821 logevent("Keyboard-interactive authentication refused");
6822 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
6823 s
->kbd_inter_refused
= TRUE
; /* don't try it again */
6827 c_write_str(ssh
, "Using keyboard-interactive authentication.\r\n");
6828 s
->kbd_inter_running
= TRUE
;
6832 if (s
->kbd_inter_running
) {
6833 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6834 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6836 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6837 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6839 if (s
->curr_prompt
== 0) {
6841 * We've got a fresh USERAUTH_INFO_REQUEST.
6842 * Display header data, and start going through
6845 char *name
, *inst
, *lang
;
6846 int name_len
, inst_len
, lang_len
;
6848 ssh_pkt_getstring(pktin
, &name
, &name_len
);
6849 ssh_pkt_getstring(pktin
, &inst
, &inst_len
);
6850 ssh_pkt_getstring(pktin
, &lang
, &lang_len
);
6852 c_write_untrusted(ssh
, name
, name_len
);
6853 c_write_str(ssh
, "\r\n");
6856 c_write_untrusted(ssh
, inst
, inst_len
);
6857 c_write_str(ssh
, "\r\n");
6859 s
->num_prompts
= ssh_pkt_getuint32(pktin
);
6863 * If there are prompts remaining in the packet,
6864 * display one and get a response.
6866 if (s
->curr_prompt
< s
->num_prompts
) {
6870 ssh_pkt_getstring(pktin
, &prompt
, &prompt_len
);
6871 if (prompt_len
> 0) {
6872 static const char trunc
[] = "<prompt truncated>: ";
6873 static const int prlen
= sizeof(s
->pwprompt
) -
6875 if (prompt_len
> prlen
) {
6876 memcpy(s
->pwprompt
, prompt
, prlen
);
6877 strcpy(s
->pwprompt
+ prlen
, trunc
);
6879 memcpy(s
->pwprompt
, prompt
, prompt_len
);
6880 s
->pwprompt
[prompt_len
] = '\0';
6884 "<server failed to send prompt>: ");
6886 s
->echo
= ssh2_pkt_getbool(pktin
);
6892 if (!s
->method
&& s
->can_passwd
) {
6893 s
->method
= AUTH_PASSWORD
;
6894 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6895 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
6896 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
6903 if (!ssh_get_line(s
->pwprompt
, s
->password
,
6904 sizeof(s
->password
), TRUE
)) {
6906 * get_line failed to get a password (for
6907 * example because one was supplied on the
6908 * command line which has already failed to
6911 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6912 ssh2_pkt_adduint32(s
->pktout
,SSH2_DISCONNECT_BY_APPLICATION
);
6913 ssh2_pkt_addstring(s
->pktout
, "No more passwords available"
6915 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6916 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6917 logevent("Unable to authenticate");
6918 connection_fatal(ssh
->frontend
,
6919 "Unable to authenticate");
6920 ssh
->close_expected
= TRUE
;
6921 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6925 int ret
; /* need not be saved across crReturn */
6926 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
6929 setup_userpass_input(ssh
, s
->password
,
6930 sizeof(s
->password
), s
->echo
);
6932 crWaitUntilV(!pktin
);
6933 ret
= process_userpass_input(ssh
, in
, inlen
);
6937 c_write_str(ssh
, "\r\n");
6941 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
6943 * We have our passphrase. Now try the actual authentication.
6945 struct ssh2_userkey
*key
;
6946 const char *error
= NULL
;
6948 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
,
6950 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
6951 if (key
== SSH2_WRONG_PASSPHRASE
) {
6952 c_write_str(ssh
, "Wrong passphrase\r\n");
6953 s
->tried_pubkey_config
= FALSE
;
6955 c_write_str(ssh
, "Unable to load private key (");
6956 c_write_str(ssh
, error
);
6957 c_write_str(ssh
, ")\r\n");
6958 s
->tried_pubkey_config
= TRUE
;
6960 /* Send a spurious AUTH_NONE to return to the top. */
6961 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6962 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6963 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6964 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6965 ssh2_pkt_send(ssh
, s
->pktout
);
6966 s
->type
= AUTH_TYPE_NONE
;
6968 unsigned char *pkblob
, *sigblob
, *sigdata
;
6969 int pkblob_len
, sigblob_len
, sigdata_len
;
6973 * We have loaded the private key and the server
6974 * has announced that it's willing to accept it.
6975 * Hallelujah. Generate a signature and send it.
6977 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6978 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6979 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6980 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6981 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6982 ssh2_pkt_addstring(s
->pktout
, key
->alg
->name
);
6983 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
6984 ssh2_pkt_addstring_start(s
->pktout
);
6985 ssh2_pkt_addstring_data(s
->pktout
, (char *)pkblob
, pkblob_len
);
6988 * The data to be signed is:
6992 * followed by everything so far placed in the
6995 sigdata_len
= s
->pktout
->length
- 5 + 4 + 20;
6996 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6998 sigdata
= snewn(sigdata_len
, unsigned char);
7000 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
7001 PUT_32BIT(sigdata
+p
, 20);
7004 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
7005 memcpy(sigdata
+p
, s
->pktout
->data
+ 5,
7006 s
->pktout
->length
- 5);
7007 p
+= s
->pktout
->length
- 5;
7008 assert(p
== sigdata_len
);
7009 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
7010 sigdata_len
, &sigblob_len
);
7011 ssh2_add_sigblob(ssh
, s
->pktout
, pkblob
, pkblob_len
,
7012 sigblob
, sigblob_len
);
7017 ssh2_pkt_send(ssh
, s
->pktout
);
7018 s
->type
= AUTH_TYPE_PUBLICKEY
;
7019 key
->alg
->freekey(key
->data
);
7021 } else if (s
->method
== AUTH_PASSWORD
) {
7023 * We pad out the password packet to 256 bytes to make
7024 * it harder for an attacker to find the length of the
7027 * Anyone using a password longer than 256 bytes
7028 * probably doesn't have much to worry about from
7029 * people who find out how long their password is!
7031 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
7032 s
->pktout
->forcepad
= 256;
7033 ssh2_pkt_addstring(s
->pktout
, s
->username
);
7034 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
7035 ssh2_pkt_addstring(s
->pktout
, "password");
7036 ssh2_pkt_addbool(s
->pktout
, FALSE
);
7037 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
7038 ssh2_pkt_addstring(s
->pktout
, s
->password
);
7039 memset(s
->password
, 0, sizeof(s
->password
));
7040 end_log_omission(ssh
, s
->pktout
);
7041 ssh2_pkt_send(ssh
, s
->pktout
);
7042 logevent("Sent password");
7043 s
->type
= AUTH_TYPE_PASSWORD
;
7044 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
7045 if (s
->curr_prompt
== 0) {
7046 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
7047 s
->pktout
->forcepad
= 256;
7048 ssh2_pkt_adduint32(s
->pktout
, s
->num_prompts
);
7050 if (s
->need_pw
) { /* only add pw if we just got one! */
7051 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
7052 ssh2_pkt_addstring(s
->pktout
, s
->password
);
7053 memset(s
->password
, 0, sizeof(s
->password
));
7054 end_log_omission(ssh
, s
->pktout
);
7057 if (s
->curr_prompt
>= s
->num_prompts
) {
7058 ssh2_pkt_send(ssh
, s
->pktout
);
7061 * If there are prompts remaining, we set
7062 * `gotit' so that we won't attempt to get
7063 * another packet. Then we go back round the
7064 * loop and will end up retrieving another
7065 * prompt out of the existing packet. Funky or
7070 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
7072 c_write_str(ssh
, "No supported authentication methods"
7073 " left to try!\r\n");
7074 logevent("No supported authentications offered."
7076 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
7077 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
7078 ssh2_pkt_addstring(s
->pktout
, "No supported authentication"
7079 " methods available");
7080 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
7081 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
7082 ssh
->close_expected
= TRUE
;
7083 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
7087 } while (!s
->we_are_in
);
7090 * Now we're authenticated for the connection protocol. The
7091 * connection protocol will automatically have started at this
7092 * point; there's no need to send SERVICE_REQUEST.
7095 ssh
->channels
= newtree234(ssh_channelcmp
);
7098 * Set up handlers for some connection protocol messages, so we
7099 * don't have to handle them repeatedly in this coroutine.
7101 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] =
7102 ssh2_msg_channel_window_adjust
;
7103 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] =
7104 ssh2_msg_global_request
;
7107 * Create the main session channel.
7109 if (!ssh
->cfg
.ssh_no_shell
) {
7110 ssh
->mainchan
= snew(struct ssh_channel
);
7111 ssh
->mainchan
->ssh
= ssh
;
7112 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
7113 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
7114 ssh2_pkt_addstring(s
->pktout
, "session");
7115 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->localid
);
7116 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7117 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
7118 ssh2_pkt_adduint32(s
->pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
7119 ssh2_pkt_send(ssh
, s
->pktout
);
7120 crWaitUntilV(pktin
);
7121 if (pktin
->type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
7122 bombout(("Server refused to open a session"));
7124 /* FIXME: error data comes back in FAILURE packet */
7126 if (ssh_pkt_getuint32(pktin
) != ssh
->mainchan
->localid
) {
7127 bombout(("Server's channel confirmation cited wrong channel"));
7130 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(pktin
);
7131 ssh
->mainchan
->halfopen
= FALSE
;
7132 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
7133 ssh
->mainchan
->closes
= 0;
7134 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
7135 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
7136 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
7137 add234(ssh
->channels
, ssh
->mainchan
);
7138 update_specials_menu(ssh
->frontend
);
7139 logevent("Opened channel for session");
7141 ssh
->mainchan
= NULL
;
7144 * Now we have a channel, make dispatch table entries for
7145 * general channel-based messages.
7147 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] =
7148 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] =
7149 ssh2_msg_channel_data
;
7150 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = ssh2_msg_channel_eof
;
7151 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = ssh2_msg_channel_close
;
7152 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] =
7153 ssh2_msg_channel_open_confirmation
;
7154 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] =
7155 ssh2_msg_channel_open_failure
;
7156 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] =
7157 ssh2_msg_channel_request
;
7158 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] =
7159 ssh2_msg_channel_open
;
7162 * Potentially enable X11 forwarding.
7164 if (ssh
->mainchan
&& ssh
->cfg
.x11_forward
) {
7165 char proto
[20], data
[64];
7166 logevent("Requesting X11 forwarding");
7167 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
7168 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
7169 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
7170 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7171 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7172 ssh2_pkt_addstring(s
->pktout
, "x11-req");
7173 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7174 ssh2_pkt_addbool(s
->pktout
, 0); /* many connections */
7175 ssh2_pkt_addstring(s
->pktout
, proto
);
7176 ssh2_pkt_addstring(s
->pktout
, data
);
7177 ssh2_pkt_adduint32(s
->pktout
, x11_get_screen_number(ssh
->cfg
.x11_display
));
7178 ssh2_pkt_send(ssh
, s
->pktout
);
7180 crWaitUntilV(pktin
);
7182 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7183 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7184 bombout(("Unexpected response to X11 forwarding request:"
7185 " packet type %d", pktin
->type
));
7188 logevent("X11 forwarding refused");
7190 logevent("X11 forwarding enabled");
7191 ssh
->X11_fwd_enabled
= TRUE
;
7196 * Enable port forwardings.
7198 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
7201 * Potentially enable agent forwarding.
7203 if (ssh
->mainchan
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
7204 logevent("Requesting OpenSSH-style agent forwarding");
7205 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7206 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7207 ssh2_pkt_addstring(s
->pktout
, "auth-agent-req@openssh.com");
7208 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7209 ssh2_pkt_send(ssh
, s
->pktout
);
7211 crWaitUntilV(pktin
);
7213 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7214 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7215 bombout(("Unexpected response to agent forwarding request:"
7216 " packet type %d", pktin
->type
));
7219 logevent("Agent forwarding refused");
7221 logevent("Agent forwarding enabled");
7222 ssh
->agentfwd_enabled
= TRUE
;
7227 * Now allocate a pty for the session.
7229 if (ssh
->mainchan
&& !ssh
->cfg
.nopty
) {
7230 /* Unpick the terminal-speed string. */
7231 /* XXX perhaps we should allow no speeds to be sent. */
7232 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
7233 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
7234 /* Build the pty request. */
7235 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7236 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7237 ssh2_pkt_addstring(s
->pktout
, "pty-req");
7238 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7239 ssh2_pkt_addstring(s
->pktout
, ssh
->cfg
.termtype
);
7240 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_width
);
7241 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_height
);
7242 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel width */
7243 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel height */
7244 ssh2_pkt_addstring_start(s
->pktout
);
7245 ssh2_pkt_addbyte(s
->pktout
, 128); /* TTY_OP_ISPEED */
7246 ssh2_pkt_adduint32(s
->pktout
, ssh
->ispeed
);
7247 ssh2_pkt_addbyte(s
->pktout
, 129); /* TTY_OP_OSPEED */
7248 ssh2_pkt_adduint32(s
->pktout
, ssh
->ospeed
);
7249 ssh2_pkt_addstring_data(s
->pktout
, "\0", 1); /* TTY_OP_END */
7250 ssh2_pkt_send(ssh
, s
->pktout
);
7251 ssh
->state
= SSH_STATE_INTERMED
;
7253 crWaitUntilV(pktin
);
7255 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7256 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7257 bombout(("Unexpected response to pty request:"
7258 " packet type %d", pktin
->type
));
7261 c_write_str(ssh
, "Server refused to allocate pty\r\n");
7262 ssh
->editing
= ssh
->echoing
= 1;
7264 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
7265 ssh
->ospeed
, ssh
->ispeed
);
7268 ssh
->editing
= ssh
->echoing
= 1;
7272 * Send environment variables.
7274 * Simplest thing here is to send all the requests at once, and
7275 * then wait for a whole bunch of successes or failures.
7277 if (ssh
->mainchan
&& *ssh
->cfg
.environmt
) {
7278 char *e
= ssh
->cfg
.environmt
;
7279 char *var
, *varend
, *val
;
7285 while (*e
&& *e
!= '\t') e
++;
7287 if (*e
== '\t') e
++;
7292 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7293 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7294 ssh2_pkt_addstring(s
->pktout
, "env");
7295 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7296 ssh2_pkt_addstring_start(s
->pktout
);
7297 ssh2_pkt_addstring_data(s
->pktout
, var
, varend
-var
);
7298 ssh2_pkt_addstring(s
->pktout
, val
);
7299 ssh2_pkt_send(ssh
, s
->pktout
);
7304 logeventf(ssh
, "Sent %d environment variables", s
->num_env
);
7307 s
->env_left
= s
->num_env
;
7309 while (s
->env_left
> 0) {
7310 crWaitUntilV(pktin
);
7312 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7313 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7314 bombout(("Unexpected response to environment request:"
7315 " packet type %d", pktin
->type
));
7325 if (s
->env_ok
== s
->num_env
) {
7326 logevent("All environment variables successfully set");
7327 } else if (s
->env_ok
== 0) {
7328 logevent("All environment variables refused");
7329 c_write_str(ssh
, "Server refused to set environment variables\r\n");
7331 logeventf(ssh
, "%d environment variables refused",
7332 s
->num_env
- s
->env_ok
);
7333 c_write_str(ssh
, "Server refused to set all environment variables\r\n");
7338 * Start a shell or a remote command. We may have to attempt
7339 * this twice if the config data has provided a second choice
7342 if (ssh
->mainchan
) while (1) {
7346 if (ssh
->fallback_cmd
) {
7347 subsys
= ssh
->cfg
.ssh_subsys2
;
7348 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
7350 subsys
= ssh
->cfg
.ssh_subsys
;
7351 cmd
= ssh
->cfg
.remote_cmd_ptr
;
7352 if (!cmd
) cmd
= ssh
->cfg
.remote_cmd
;
7355 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7356 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7358 ssh2_pkt_addstring(s
->pktout
, "subsystem");
7359 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7360 ssh2_pkt_addstring(s
->pktout
, cmd
);
7362 ssh2_pkt_addstring(s
->pktout
, "exec");
7363 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7364 ssh2_pkt_addstring(s
->pktout
, cmd
);
7366 ssh2_pkt_addstring(s
->pktout
, "shell");
7367 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7369 ssh2_pkt_send(ssh
, s
->pktout
);
7371 crWaitUntilV(pktin
);
7373 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7374 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7375 bombout(("Unexpected response to shell/command request:"
7376 " packet type %d", pktin
->type
));
7380 * We failed to start the command. If this is the
7381 * fallback command, we really are finished; if it's
7382 * not, and if the fallback command exists, try falling
7383 * back to it before complaining.
7385 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
7386 logevent("Primary command failed; attempting fallback");
7387 ssh
->fallback_cmd
= TRUE
;
7390 bombout(("Server refused to start a shell/command"));
7393 logevent("Started a shell/command");
7398 ssh
->state
= SSH_STATE_SESSION
;
7399 if (ssh
->size_needed
)
7400 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
7401 if (ssh
->eof_needed
)
7402 ssh_special(ssh
, TS_EOF
);
7408 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
7413 s
->try_send
= FALSE
;
7417 * _All_ the connection-layer packets we expect to
7418 * receive are now handled by the dispatch table.
7419 * Anything that reaches here must be bogus.
7422 bombout(("Strange packet received: type %d", pktin
->type
));
7424 } else if (ssh
->mainchan
) {
7426 * We have spare data. Add it to the channel buffer.
7428 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
7433 struct ssh_channel
*c
;
7435 * Try to send data on all channels if we can.
7437 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++)
7438 ssh2_try_send_and_unthrottle(c
);
7446 * Handlers for SSH-2 messages that might arrive at any moment.
7448 static void ssh2_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
7450 /* log reason code in disconnect message */
7452 int nowlen
, reason
, msglen
;
7454 reason
= ssh_pkt_getuint32(pktin
);
7455 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7457 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
7458 buf
= dupprintf("Received disconnect message (%s)",
7459 ssh2_disconnect_reasons
[reason
]);
7461 buf
= dupprintf("Received disconnect message (unknown"
7462 " type %d)", reason
);
7466 buf
= dupprintf("Disconnection message text: %n%.*s",
7467 &nowlen
, msglen
, msg
);
7469 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7471 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
7472 ssh2_disconnect_reasons
[reason
] : "unknown",
7477 static void ssh2_msg_debug(Ssh ssh
, struct Packet
*pktin
)
7479 /* log the debug message */
7484 /* XXX maybe we should actually take notice of this */
7485 always_display
= ssh2_pkt_getbool(pktin
);
7486 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7488 logeventf(ssh
, "Remote debug message: %.*s", msglen
, msg
);
7491 static void ssh2_msg_something_unimplemented(Ssh ssh
, struct Packet
*pktin
)
7493 struct Packet
*pktout
;
7494 pktout
= ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
7495 ssh2_pkt_adduint32(pktout
, pktin
->sequence
);
7497 * UNIMPLEMENTED messages MUST appear in the same order as the
7498 * messages they respond to. Hence, never queue them.
7500 ssh2_pkt_send_noqueue(ssh
, pktout
);
7504 * Handle the top-level SSH-2 protocol.
7506 static void ssh2_protocol_setup(Ssh ssh
)
7511 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7513 for (i
= 0; i
< 256; i
++)
7514 ssh
->packet_dispatch
[i
] = ssh2_msg_something_unimplemented
;
7517 * Any message we actually understand, we set to NULL so that
7518 * the coroutines will get it.
7520 ssh
->packet_dispatch
[SSH2_MSG_UNIMPLEMENTED
] = NULL
;
7521 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_REQUEST
] = NULL
;
7522 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_ACCEPT
] = NULL
;
7523 ssh
->packet_dispatch
[SSH2_MSG_KEXINIT
] = NULL
;
7524 ssh
->packet_dispatch
[SSH2_MSG_NEWKEYS
] = NULL
;
7525 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_INIT
] = NULL
;
7526 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_REPLY
] = NULL
;
7527 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7528 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7529 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_INIT
] = NULL
;
7530 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_REPLY
] = NULL
;
7531 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_REQUEST
] = NULL
;
7532 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_FAILURE
] = NULL
;
7533 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_SUCCESS
] = NULL
;
7534 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
7535 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_PK_OK
] = NULL
;
7536 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7537 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7538 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_INFO_RESPONSE
] = NULL
;
7539 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] = NULL
;
7540 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_SUCCESS
] = NULL
;
7541 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_FAILURE
] = NULL
;
7542 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] = NULL
;
7543 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] = NULL
;
7544 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] = NULL
;
7545 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] = NULL
;
7546 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] = NULL
;
7547 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] = NULL
;
7548 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = NULL
;
7549 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = NULL
;
7550 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] = NULL
;
7551 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_SUCCESS
] = NULL
;
7552 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_FAILURE
] = NULL
;
7555 * These special message types we install handlers for.
7557 ssh
->packet_dispatch
[SSH2_MSG_DISCONNECT
] = ssh2_msg_disconnect
;
7558 ssh
->packet_dispatch
[SSH2_MSG_IGNORE
] = ssh_msg_ignore
; /* shared with SSH-1 */
7559 ssh
->packet_dispatch
[SSH2_MSG_DEBUG
] = ssh2_msg_debug
;
7562 static void ssh2_timer(void *ctx
, long now
)
7566 if (ssh
->state
== SSH_STATE_CLOSED
)
7569 if (!ssh
->kex_in_progress
&& ssh
->cfg
.ssh_rekey_time
!= 0 &&
7570 now
- ssh
->next_rekey
>= 0) {
7571 do_ssh2_transport(ssh
, "timeout", -1, NULL
);
7575 static void ssh2_protocol(Ssh ssh
, void *vin
, int inlen
,
7576 struct Packet
*pktin
)
7578 unsigned char *in
= (unsigned char *)vin
;
7579 if (ssh
->state
== SSH_STATE_CLOSED
)
7583 ssh
->incoming_data_size
+= pktin
->encrypted_len
;
7584 if (!ssh
->kex_in_progress
&&
7585 ssh
->max_data_size
!= 0 &&
7586 ssh
->incoming_data_size
> ssh
->max_data_size
)
7587 do_ssh2_transport(ssh
, "too much data received", -1, NULL
);
7590 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
7591 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
7595 if (!ssh
->protocol_initial_phase_done
||
7596 (pktin
&& pktin
->type
>= 20 && pktin
->type
< 50)) {
7597 if (do_ssh2_transport(ssh
, in
, inlen
, pktin
) &&
7598 !ssh
->protocol_initial_phase_done
) {
7599 ssh
->protocol_initial_phase_done
= TRUE
;
7601 * Allow authconn to initialise itself.
7603 do_ssh2_authconn(ssh
, NULL
, 0, NULL
);
7606 do_ssh2_authconn(ssh
, in
, inlen
, pktin
);
7611 * Called to set up the connection.
7613 * Returns an error message, or NULL on success.
7615 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
7617 char *host
, int port
, char **realhost
, int nodelay
,
7623 ssh
= snew(struct ssh_tag
);
7624 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7625 ssh
->version
= 0; /* when not ready yet */
7628 ssh
->v1_cipher_ctx
= NULL
;
7629 ssh
->crcda_ctx
= NULL
;
7630 ssh
->cscipher
= NULL
;
7631 ssh
->cs_cipher_ctx
= NULL
;
7632 ssh
->sccipher
= NULL
;
7633 ssh
->sc_cipher_ctx
= NULL
;
7635 ssh
->cs_mac_ctx
= NULL
;
7637 ssh
->sc_mac_ctx
= NULL
;
7639 ssh
->cs_comp_ctx
= NULL
;
7641 ssh
->sc_comp_ctx
= NULL
;
7643 ssh
->kex_ctx
= NULL
;
7644 ssh
->hostkey
= NULL
;
7646 ssh
->close_expected
= FALSE
;
7647 ssh
->state
= SSH_STATE_PREPACKET
;
7648 ssh
->size_needed
= FALSE
;
7649 ssh
->eof_needed
= FALSE
;
7652 ssh
->deferred_send_data
= NULL
;
7653 ssh
->deferred_len
= 0;
7654 ssh
->deferred_size
= 0;
7655 ssh
->fallback_cmd
= 0;
7657 ssh
->x11auth
= NULL
;
7658 ssh
->v1_compressing
= FALSE
;
7659 ssh
->v2_outgoing_sequence
= 0;
7660 ssh
->ssh1_rdpkt_crstate
= 0;
7661 ssh
->ssh2_rdpkt_crstate
= 0;
7662 ssh
->do_ssh_init_crstate
= 0;
7663 ssh
->ssh_gotdata_crstate
= 0;
7664 ssh
->do_ssh1_connection_crstate
= 0;
7665 ssh
->do_ssh1_login_crstate
= 0;
7666 ssh
->do_ssh2_transport_crstate
= 0;
7667 ssh
->do_ssh2_authconn_crstate
= 0;
7668 ssh
->do_ssh_init_state
= NULL
;
7669 ssh
->do_ssh1_login_state
= NULL
;
7670 ssh
->do_ssh2_transport_state
= NULL
;
7671 ssh
->do_ssh2_authconn_state
= NULL
;
7672 ssh
->mainchan
= NULL
;
7673 ssh
->throttled_all
= 0;
7674 ssh
->v1_stdout_throttling
= 0;
7676 ssh
->queuelen
= ssh
->queuesize
= 0;
7677 ssh
->queueing
= FALSE
;
7678 ssh
->qhead
= ssh
->qtail
= NULL
;
7679 ssh
->deferred_rekey_reason
= NULL
;
7680 bufchain_init(&ssh
->queued_incoming_data
);
7681 ssh
->frozen
= FALSE
;
7683 *backend_handle
= ssh
;
7686 if (crypto_startup() == 0)
7687 return "Microsoft high encryption pack not installed!";
7690 ssh
->frontend
= frontend_handle
;
7691 ssh
->term_width
= ssh
->cfg
.width
;
7692 ssh
->term_height
= ssh
->cfg
.height
;
7694 ssh
->channels
= NULL
;
7695 ssh
->rportfwds
= NULL
;
7696 ssh
->portfwds
= NULL
;
7701 ssh
->v1_throttle_count
= 0;
7702 ssh
->overall_bufsize
= 0;
7703 ssh
->fallback_cmd
= 0;
7705 ssh
->protocol
= NULL
;
7707 ssh
->protocol_initial_phase_done
= FALSE
;
7711 ssh
->incoming_data_size
= ssh
->outgoing_data_size
=
7712 ssh
->deferred_data_size
= 0L;
7713 ssh
->max_data_size
= parse_blocksize(ssh
->cfg
.ssh_rekey_data
);
7714 ssh
->kex_in_progress
= FALSE
;
7716 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
7725 static void ssh_free(void *handle
)
7727 Ssh ssh
= (Ssh
) handle
;
7728 struct ssh_channel
*c
;
7729 struct ssh_rportfwd
*pf
;
7731 if (ssh
->v1_cipher_ctx
)
7732 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
7733 if (ssh
->cs_cipher_ctx
)
7734 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
7735 if (ssh
->sc_cipher_ctx
)
7736 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
7737 if (ssh
->cs_mac_ctx
)
7738 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
7739 if (ssh
->sc_mac_ctx
)
7740 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
7741 if (ssh
->cs_comp_ctx
) {
7743 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
7745 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
7747 if (ssh
->sc_comp_ctx
) {
7749 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
7751 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
7754 dh_cleanup(ssh
->kex_ctx
);
7755 sfree(ssh
->savedhost
);
7757 while (ssh
->queuelen
-- > 0)
7758 ssh_free_packet(ssh
->queue
[ssh
->queuelen
]);
7761 while (ssh
->qhead
) {
7762 struct queued_handler
*qh
= ssh
->qhead
;
7763 ssh
->qhead
= qh
->next
;
7766 ssh
->qhead
= ssh
->qtail
= NULL
;
7768 if (ssh
->channels
) {
7769 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
7772 if (c
->u
.x11
.s
!= NULL
)
7773 x11_close(c
->u
.x11
.s
);
7776 if (c
->u
.pfd
.s
!= NULL
)
7777 pfd_close(c
->u
.pfd
.s
);
7782 freetree234(ssh
->channels
);
7783 ssh
->channels
= NULL
;
7786 if (ssh
->rportfwds
) {
7787 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
7789 freetree234(ssh
->rportfwds
);
7790 ssh
->rportfwds
= NULL
;
7792 sfree(ssh
->deferred_send_data
);
7794 x11_free_auth(ssh
->x11auth
);
7795 sfree(ssh
->do_ssh_init_state
);
7796 sfree(ssh
->do_ssh1_login_state
);
7797 sfree(ssh
->do_ssh2_transport_state
);
7798 sfree(ssh
->do_ssh2_authconn_state
);
7799 if (ssh
->crcda_ctx
) {
7800 crcda_free_context(ssh
->crcda_ctx
);
7801 ssh
->crcda_ctx
= NULL
;
7804 ssh_do_close(ssh
, TRUE
);
7805 expire_timer_context(ssh
);
7807 pinger_free(ssh
->pinger
);
7808 bufchain_clear(&ssh
->queued_incoming_data
);
7815 * Reconfigure the SSH backend.
7817 static void ssh_reconfig(void *handle
, Config
*cfg
)
7819 Ssh ssh
= (Ssh
) handle
;
7820 char *rekeying
= NULL
, rekey_mandatory
= FALSE
;
7821 unsigned long old_max_data_size
;
7823 pinger_reconfig(ssh
->pinger
, &ssh
->cfg
, cfg
);
7824 ssh_setup_portfwd(ssh
, cfg
);
7826 if (ssh
->cfg
.ssh_rekey_time
!= cfg
->ssh_rekey_time
&&
7827 cfg
->ssh_rekey_time
!= 0) {
7828 long new_next
= ssh
->last_rekey
+ cfg
->ssh_rekey_time
*60*TICKSPERSEC
;
7829 long now
= GETTICKCOUNT();
7831 if (new_next
- now
< 0) {
7832 rekeying
= "timeout shortened";
7834 ssh
->next_rekey
= schedule_timer(new_next
- now
, ssh2_timer
, ssh
);
7838 old_max_data_size
= ssh
->max_data_size
;
7839 ssh
->max_data_size
= parse_blocksize(cfg
->ssh_rekey_data
);
7840 if (old_max_data_size
!= ssh
->max_data_size
&&
7841 ssh
->max_data_size
!= 0) {
7842 if (ssh
->outgoing_data_size
> ssh
->max_data_size
||
7843 ssh
->incoming_data_size
> ssh
->max_data_size
)
7844 rekeying
= "data limit lowered";
7847 if (ssh
->cfg
.compression
!= cfg
->compression
) {
7848 rekeying
= "compression setting changed";
7849 rekey_mandatory
= TRUE
;
7852 if (ssh
->cfg
.ssh2_des_cbc
!= cfg
->ssh2_des_cbc
||
7853 memcmp(ssh
->cfg
.ssh_cipherlist
, cfg
->ssh_cipherlist
,
7854 sizeof(ssh
->cfg
.ssh_cipherlist
))) {
7855 rekeying
= "cipher settings changed";
7856 rekey_mandatory
= TRUE
;
7859 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7862 if (!ssh
->kex_in_progress
) {
7863 do_ssh2_transport(ssh
, rekeying
, -1, NULL
);
7864 } else if (rekey_mandatory
) {
7865 ssh
->deferred_rekey_reason
= rekeying
;
7871 * Called to send data down the Telnet connection.
7873 static int ssh_send(void *handle
, char *buf
, int len
)
7875 Ssh ssh
= (Ssh
) handle
;
7877 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7880 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
7882 return ssh_sendbuffer(ssh
);
7886 * Called to query the current amount of buffered stdin data.
7888 static int ssh_sendbuffer(void *handle
)
7890 Ssh ssh
= (Ssh
) handle
;
7893 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7897 * If the SSH socket itself has backed up, add the total backup
7898 * size on that to any individual buffer on the stdin channel.
7901 if (ssh
->throttled_all
)
7902 override_value
= ssh
->overall_bufsize
;
7904 if (ssh
->version
== 1) {
7905 return override_value
;
7906 } else if (ssh
->version
== 2) {
7907 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
7908 return override_value
;
7910 return (override_value
+
7911 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
7918 * Called to set the size of the window from SSH's POV.
7920 static void ssh_size(void *handle
, int width
, int height
)
7922 Ssh ssh
= (Ssh
) handle
;
7923 struct Packet
*pktout
;
7925 ssh
->term_width
= width
;
7926 ssh
->term_height
= height
;
7928 switch (ssh
->state
) {
7929 case SSH_STATE_BEFORE_SIZE
:
7930 case SSH_STATE_PREPACKET
:
7931 case SSH_STATE_CLOSED
:
7932 break; /* do nothing */
7933 case SSH_STATE_INTERMED
:
7934 ssh
->size_needed
= TRUE
; /* buffer for later */
7936 case SSH_STATE_SESSION
:
7937 if (!ssh
->cfg
.nopty
) {
7938 if (ssh
->version
== 1) {
7939 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
7940 PKT_INT
, ssh
->term_height
,
7941 PKT_INT
, ssh
->term_width
,
7942 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
7943 } else if (ssh
->mainchan
) {
7944 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7945 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7946 ssh2_pkt_addstring(pktout
, "window-change");
7947 ssh2_pkt_addbool(pktout
, 0);
7948 ssh2_pkt_adduint32(pktout
, ssh
->term_width
);
7949 ssh2_pkt_adduint32(pktout
, ssh
->term_height
);
7950 ssh2_pkt_adduint32(pktout
, 0);
7951 ssh2_pkt_adduint32(pktout
, 0);
7952 ssh2_pkt_send(ssh
, pktout
);
7960 * Return a list of the special codes that make sense in this
7963 static const struct telnet_special
*ssh_get_specials(void *handle
)
7965 static const struct telnet_special ssh1_ignore_special
[] = {
7966 {"IGNORE message", TS_NOP
}
7968 static const struct telnet_special ssh2_transport_specials
[] = {
7969 {"IGNORE message", TS_NOP
},
7970 {"Repeat key exchange", TS_REKEY
},
7972 static const struct telnet_special ssh2_session_specials
[] = {
7975 /* These are the signal names defined by draft-ietf-secsh-connect-23.
7976 * They include all the ISO C signals, but are a subset of the POSIX
7977 * required signals. */
7978 {"SIGINT (Interrupt)", TS_SIGINT
},
7979 {"SIGTERM (Terminate)", TS_SIGTERM
},
7980 {"SIGKILL (Kill)", TS_SIGKILL
},
7981 {"SIGQUIT (Quit)", TS_SIGQUIT
},
7982 {"SIGHUP (Hangup)", TS_SIGHUP
},
7983 {"More signals", TS_SUBMENU
},
7984 {"SIGABRT", TS_SIGABRT
}, {"SIGALRM", TS_SIGALRM
},
7985 {"SIGFPE", TS_SIGFPE
}, {"SIGILL", TS_SIGILL
},
7986 {"SIGPIPE", TS_SIGPIPE
}, {"SIGSEGV", TS_SIGSEGV
},
7987 {"SIGUSR1", TS_SIGUSR1
}, {"SIGUSR2", TS_SIGUSR2
},
7990 static const struct telnet_special specials_end
[] = {
7993 /* XXX review this length for any changes: */
7994 static struct telnet_special ssh_specials
[lenof(ssh2_transport_specials
) +
7995 lenof(ssh2_session_specials
) +
7996 lenof(specials_end
)];
7997 Ssh ssh
= (Ssh
) handle
;
7999 #define ADD_SPECIALS(name) \
8001 assert((i + lenof(name)) <= lenof(ssh_specials)); \
8002 memcpy(&ssh_specials[i], name, sizeof name); \
8006 if (ssh
->version
== 1) {
8007 /* Don't bother offering IGNORE if we've decided the remote
8008 * won't cope with it, since we wouldn't bother sending it if
8010 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
8011 ADD_SPECIALS(ssh1_ignore_special
);
8012 } else if (ssh
->version
== 2) {
8013 ADD_SPECIALS(ssh2_transport_specials
);
8015 ADD_SPECIALS(ssh2_session_specials
);
8016 } /* else we're not ready yet */
8019 ADD_SPECIALS(specials_end
);
8020 return ssh_specials
;
8028 * Send Telnet special codes. TS_EOF is useful for `plink', so you
8029 * can send an EOF and collect resulting output (e.g. `plink
8032 static void ssh_special(void *handle
, Telnet_Special code
)
8034 Ssh ssh
= (Ssh
) handle
;
8035 struct Packet
*pktout
;
8037 if (code
== TS_EOF
) {
8038 if (ssh
->state
!= SSH_STATE_SESSION
) {
8040 * Buffer the EOF in case we are pre-SESSION, so we can
8041 * send it as soon as we reach SESSION.
8044 ssh
->eof_needed
= TRUE
;
8047 if (ssh
->version
== 1) {
8048 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
8049 } else if (ssh
->mainchan
) {
8050 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
8051 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8052 ssh2_pkt_send(ssh
, pktout
);
8053 ssh
->send_ok
= 0; /* now stop trying to read from stdin */
8055 logevent("Sent EOF message");
8056 } else if (code
== TS_PING
|| code
== TS_NOP
) {
8057 if (ssh
->state
== SSH_STATE_CLOSED
8058 || ssh
->state
== SSH_STATE_PREPACKET
) return;
8059 if (ssh
->version
== 1) {
8060 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
8061 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
8063 pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
8064 ssh2_pkt_addstring_start(pktout
);
8065 ssh2_pkt_send_noqueue(ssh
, pktout
);
8067 } else if (code
== TS_REKEY
) {
8068 if (!ssh
->kex_in_progress
&& ssh
->version
== 2) {
8069 do_ssh2_transport(ssh
, "at user request", -1, NULL
);
8071 } else if (code
== TS_BRK
) {
8072 if (ssh
->state
== SSH_STATE_CLOSED
8073 || ssh
->state
== SSH_STATE_PREPACKET
) return;
8074 if (ssh
->version
== 1) {
8075 logevent("Unable to send BREAK signal in SSH-1");
8076 } else if (ssh
->mainchan
) {
8077 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
8078 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8079 ssh2_pkt_addstring(pktout
, "break");
8080 ssh2_pkt_addbool(pktout
, 0);
8081 ssh2_pkt_adduint32(pktout
, 0); /* default break length */
8082 ssh2_pkt_send(ssh
, pktout
);
8085 /* Is is a POSIX signal? */
8086 char *signame
= NULL
;
8087 if (code
== TS_SIGABRT
) signame
= "ABRT";
8088 if (code
== TS_SIGALRM
) signame
= "ALRM";
8089 if (code
== TS_SIGFPE
) signame
= "FPE";
8090 if (code
== TS_SIGHUP
) signame
= "HUP";
8091 if (code
== TS_SIGILL
) signame
= "ILL";
8092 if (code
== TS_SIGINT
) signame
= "INT";
8093 if (code
== TS_SIGKILL
) signame
= "KILL";
8094 if (code
== TS_SIGPIPE
) signame
= "PIPE";
8095 if (code
== TS_SIGQUIT
) signame
= "QUIT";
8096 if (code
== TS_SIGSEGV
) signame
= "SEGV";
8097 if (code
== TS_SIGTERM
) signame
= "TERM";
8098 if (code
== TS_SIGUSR1
) signame
= "USR1";
8099 if (code
== TS_SIGUSR2
) signame
= "USR2";
8100 /* The SSH-2 protocol does in principle support arbitrary named
8101 * signals, including signame@domain, but we don't support those. */
8103 /* It's a signal. */
8104 if (ssh
->version
== 2 && ssh
->mainchan
) {
8105 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
8106 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8107 ssh2_pkt_addstring(pktout
, "signal");
8108 ssh2_pkt_addbool(pktout
, 0);
8109 ssh2_pkt_addstring(pktout
, signame
);
8110 ssh2_pkt_send(ssh
, pktout
);
8111 logeventf(ssh
, "Sent signal SIG%s", signame
);
8114 /* Never heard of it. Do nothing */
8119 void *new_sock_channel(void *handle
, Socket s
)
8121 Ssh ssh
= (Ssh
) handle
;
8122 struct ssh_channel
*c
;
8123 c
= snew(struct ssh_channel
);
8128 c
->localid
= alloc_channel_id(ssh
);
8130 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
8132 bufchain_init(&c
->v
.v2
.outbuffer
);
8133 add234(ssh
->channels
, c
);
8139 * This is called when stdout/stderr (the entity to which
8140 * from_backend sends data) manages to clear some backlog.
8142 static void ssh_unthrottle(void *handle
, int bufsize
)
8144 Ssh ssh
= (Ssh
) handle
;
8145 if (ssh
->version
== 1) {
8146 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
8147 ssh
->v1_stdout_throttling
= 0;
8148 ssh1_throttle(ssh
, -1);
8151 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
8152 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
8156 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
8158 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
8160 struct Packet
*pktout
;
8162 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
8164 if (ssh
->version
== 1) {
8165 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
8166 PKT_INT
, c
->localid
,
8169 /* PKT_STR, <org:orgport>, */
8172 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
8173 ssh2_pkt_addstring(pktout
, "direct-tcpip");
8174 ssh2_pkt_adduint32(pktout
, c
->localid
);
8175 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
8176 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);/* our window size */
8177 ssh2_pkt_adduint32(pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
8178 ssh2_pkt_addstring(pktout
, hostname
);
8179 ssh2_pkt_adduint32(pktout
, port
);
8181 * We make up values for the originator data; partly it's
8182 * too much hassle to keep track, and partly I'm not
8183 * convinced the server should be told details like that
8184 * about my local network configuration.
8186 ssh2_pkt_addstring(pktout
, "client-side-connection");
8187 ssh2_pkt_adduint32(pktout
, 0);
8188 ssh2_pkt_send(ssh
, pktout
);
8192 static Socket
ssh_socket(void *handle
)
8194 Ssh ssh
= (Ssh
) handle
;
8198 static int ssh_sendok(void *handle
)
8200 Ssh ssh
= (Ssh
) handle
;
8201 return ssh
->send_ok
;
8204 static int ssh_ldisc(void *handle
, int option
)
8206 Ssh ssh
= (Ssh
) handle
;
8207 if (option
== LD_ECHO
)
8208 return ssh
->echoing
;
8209 if (option
== LD_EDIT
)
8210 return ssh
->editing
;
8214 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
8216 Ssh ssh
= (Ssh
) handle
;
8220 static void ssh_provide_logctx(void *handle
, void *logctx
)
8222 Ssh ssh
= (Ssh
) handle
;
8223 ssh
->logctx
= logctx
;
8226 static int ssh_return_exitcode(void *handle
)
8228 Ssh ssh
= (Ssh
) handle
;
8232 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
8236 * cfg_info for SSH is the currently running version of the
8237 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
8239 static int ssh_cfg_info(void *handle
)
8241 Ssh ssh
= (Ssh
) handle
;
8242 return ssh
->version
;
8246 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
8247 * that fails. This variable is the means by which scp.c can reach
8248 * into the SSH code and find out which one it got.
8250 extern int ssh_fallback_cmd(void *handle
)
8252 Ssh ssh
= (Ssh
) handle
;
8253 return ssh
->fallback_cmd
;
8256 Backend ssh_backend
= {
8266 ssh_return_exitcode
,