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
*ssh1_pkt_init(int pkt_type
);
311 static struct Packet
*ssh2_pkt_init(int pkt_type
);
312 static void ssh_pkt_ensure(struct Packet
*, int length
);
313 static void ssh_pkt_adddata(struct Packet
*, void *data
, int len
);
314 static void ssh_pkt_addbyte(struct Packet
*, unsigned char value
);
315 static void ssh2_pkt_addbool(struct Packet
*, unsigned char value
);
316 static void ssh_pkt_adduint32(struct Packet
*, unsigned long value
);
317 static void ssh_pkt_addstring_start(struct Packet
*);
318 static void ssh_pkt_addstring_str(struct Packet
*, char *data
);
319 static void ssh_pkt_addstring_data(struct Packet
*, char *data
, int len
);
320 static void ssh_pkt_addstring(struct Packet
*, char *data
);
321 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
);
322 static void ssh1_pkt_addmp(struct Packet
*, Bignum b
);
323 static void ssh2_pkt_addmp(struct Packet
*, Bignum b
);
324 static int ssh2_pkt_construct(Ssh
, struct Packet
*);
325 static void ssh2_pkt_send(Ssh
, struct Packet
*);
326 static void ssh2_pkt_send_noqueue(Ssh
, struct Packet
*);
327 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
328 struct Packet
*pktin
);
329 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
330 struct Packet
*pktin
);
333 * Buffer management constants. There are several of these for
334 * various different purposes:
336 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
337 * on a local data stream before we throttle the whole SSH
338 * connection (in SSH-1 only). Throttling the whole connection is
339 * pretty drastic so we set this high in the hope it won't
342 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
343 * on the SSH connection itself before we defensively throttle
344 * _all_ local data streams. This is pretty drastic too (though
345 * thankfully unlikely in SSH-2 since the window mechanism should
346 * ensure that the server never has any need to throttle its end
347 * of the connection), so we set this high as well.
349 * - OUR_V2_WINSIZE is the maximum window size we present on SSH-2
353 #define SSH1_BUFFER_LIMIT 32768
354 #define SSH_MAX_BACKLOG 32768
355 #define OUR_V2_WINSIZE 16384
356 #define OUR_V2_MAXPKT 0x4000UL
358 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
360 const static struct ssh_mac
*macs
[] = {
363 const static struct ssh_mac
*buggymacs
[] = {
364 &ssh_sha1_buggy
, &ssh_md5
367 static void *ssh_comp_none_init(void)
371 static void ssh_comp_none_cleanup(void *handle
)
374 static int ssh_comp_none_block(void *handle
, unsigned char *block
, int len
,
375 unsigned char **outblock
, int *outlen
)
379 static int ssh_comp_none_disable(void *handle
)
383 const static struct ssh_compress ssh_comp_none
= {
385 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
386 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
387 ssh_comp_none_disable
, NULL
389 extern const struct ssh_compress ssh_zlib
;
390 const static struct ssh_compress
*compressions
[] = {
391 &ssh_zlib
, &ssh_comp_none
394 enum { /* channel types */
399 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
403 * 2-3-4 tree storing channels.
406 Ssh ssh
; /* pointer back to main context */
407 unsigned remoteid
, localid
;
409 /* True if we opened this channel but server hasn't confirmed. */
412 * In SSH-1, this value contains four bits:
414 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
415 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
416 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
417 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
419 * A channel is completely finished with when all four bits are set.
423 struct ssh1_data_channel
{
426 struct ssh2_data_channel
{
428 unsigned remwindow
, remmaxpkt
;
433 struct ssh_agent_channel
{
434 unsigned char *message
;
435 unsigned char msglen
[4];
436 unsigned lensofar
, totallen
;
438 struct ssh_x11_channel
{
441 struct ssh_pfd_channel
{
448 * 2-3-4 tree storing remote->local port forwardings. SSH-1 and SSH-2
449 * use this structure in different ways, reflecting SSH-2's
450 * altogether saner approach to port forwarding.
452 * In SSH-1, you arrange a remote forwarding by sending the server
453 * the remote port number, and the local destination host:port.
454 * When a connection comes in, the server sends you back that
455 * host:port pair, and you connect to it. This is a ready-made
456 * security hole if you're not on the ball: a malicious server
457 * could send you back _any_ host:port pair, so if you trustingly
458 * connect to the address it gives you then you've just opened the
459 * entire inside of your corporate network just by connecting
460 * through it to a dodgy SSH server. Hence, we must store a list of
461 * host:port pairs we _are_ trying to forward to, and reject a
462 * connection request from the server if it's not in the list.
464 * In SSH-2, each side of the connection minds its own business and
465 * doesn't send unnecessary information to the other. You arrange a
466 * remote forwarding by sending the server just the remote port
467 * number. When a connection comes in, the server tells you which
468 * of its ports was connected to; and _you_ have to remember what
469 * local host:port pair went with that port number.
471 * Hence, in SSH-1 this structure is indexed by destination
472 * host:port pair, whereas in SSH-2 it is indexed by source port.
474 struct ssh_portfwd
; /* forward declaration */
476 struct ssh_rportfwd
{
477 unsigned sport
, dport
;
480 struct ssh_portfwd
*pfrec
;
482 #define free_rportfwd(pf) ( \
483 ((pf) ? (sfree((pf)->sportdesc)) : (void)0 ), sfree(pf) )
486 * Separately to the rportfwd tree (which is for looking up port
487 * open requests from the server), a tree of _these_ structures is
488 * used to keep track of all the currently open port forwardings,
489 * so that we can reconfigure in mid-session if the user requests
493 enum { DESTROY
, KEEP
, CREATE
} status
;
495 unsigned sport
, dport
;
498 struct ssh_rportfwd
*remote
;
502 #define free_portfwd(pf) ( \
503 ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr), \
504 sfree((pf)->sserv), sfree((pf)->dserv)) : (void)0 ), sfree(pf) )
507 long length
; /* length of `data' actually used */
508 long forcepad
; /* SSH-2: force padding to at least this length */
509 int type
; /* only used for incoming packets */
510 unsigned long sequence
; /* SSH-2 incoming sequence number */
511 unsigned char *data
; /* allocated storage */
512 unsigned char *body
; /* offset of payload within `data' */
513 long savedpos
; /* temporary index into `data' (for strings) */
514 long maxlen
; /* amount of storage allocated for `data' */
515 long encrypted_len
; /* for SSH-2 total-size counting */
518 * State associated with packet logging
522 struct logblank_t
*blanks
;
525 static void ssh1_protocol(Ssh ssh
, void *vin
, int inlen
,
526 struct Packet
*pktin
);
527 static void ssh2_protocol(Ssh ssh
, void *vin
, int inlen
,
528 struct Packet
*pktin
);
529 static void ssh1_protocol_setup(Ssh ssh
);
530 static void ssh2_protocol_setup(Ssh ssh
);
531 static void ssh_size(void *handle
, int width
, int height
);
532 static void ssh_special(void *handle
, Telnet_Special
);
533 static int ssh2_try_send(struct ssh_channel
*c
);
534 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
535 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
536 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
537 static int ssh_sendbuffer(void *handle
);
538 static int ssh_do_close(Ssh ssh
, int notify_exit
);
539 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
);
540 static int ssh2_pkt_getbool(struct Packet
*pkt
);
541 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
);
542 static void ssh2_timer(void *ctx
, long now
);
543 static int do_ssh2_transport(Ssh ssh
, void *vin
, int inlen
,
544 struct Packet
*pktin
);
546 struct rdpkt1_state_tag
{
547 long len
, pad
, biglen
, to_read
;
548 unsigned long realcrc
, gotcrc
;
552 struct Packet
*pktin
;
555 struct rdpkt2_state_tag
{
556 long len
, pad
, payload
, packetlen
, maclen
;
559 unsigned long incoming_sequence
;
560 struct Packet
*pktin
;
563 typedef void (*handler_fn_t
)(Ssh ssh
, struct Packet
*pktin
);
564 typedef void (*chandler_fn_t
)(Ssh ssh
, struct Packet
*pktin
, void *ctx
);
566 struct queued_handler
;
567 struct queued_handler
{
569 chandler_fn_t handler
;
571 struct queued_handler
*next
;
575 const struct plug_function_table
*fn
;
576 /* the above field _must_ be first in the structure */
578 SHA_State exhash
, exhashbase
;
585 unsigned char session_key
[32];
587 int v1_remote_protoflags
;
588 int v1_local_protoflags
;
589 int agentfwd_enabled
;
592 const struct ssh_cipher
*cipher
;
595 const struct ssh2_cipher
*cscipher
, *sccipher
;
596 void *cs_cipher_ctx
, *sc_cipher_ctx
;
597 const struct ssh_mac
*csmac
, *scmac
;
598 void *cs_mac_ctx
, *sc_mac_ctx
;
599 const struct ssh_compress
*cscomp
, *sccomp
;
600 void *cs_comp_ctx
, *sc_comp_ctx
;
601 const struct ssh_kex
*kex
;
602 const struct ssh_signkey
*hostkey
;
603 unsigned char v2_session_id
[20];
609 int echoing
, editing
;
613 int ospeed
, ispeed
; /* temporaries */
614 int term_width
, term_height
;
616 tree234
*channels
; /* indexed by local id */
617 struct ssh_channel
*mainchan
; /* primary session channel */
621 tree234
*rportfwds
, *portfwds
;
625 SSH_STATE_BEFORE_SIZE
,
631 int size_needed
, eof_needed
;
633 struct Packet
**queue
;
634 int queuelen
, queuesize
;
636 unsigned char *deferred_send_data
;
637 int deferred_len
, deferred_size
;
640 * Gross hack: pscp will try to start SFTP but fall back to
641 * scp1 if that fails. This variable is the means by which
642 * scp.c can reach into the SSH code and find out which one it
648 * Used for username and password input.
650 char *userpass_input_buffer
;
651 int userpass_input_buflen
;
652 int userpass_input_bufpos
;
653 int userpass_input_echo
;
660 int v1_throttle_count
;
663 int v1_stdout_throttling
;
664 unsigned long v2_outgoing_sequence
;
666 int ssh1_rdpkt_crstate
;
667 int ssh2_rdpkt_crstate
;
668 int do_ssh_init_crstate
;
669 int ssh_gotdata_crstate
;
670 int do_ssh1_login_crstate
;
671 int do_ssh1_connection_crstate
;
672 int do_ssh2_transport_crstate
;
673 int do_ssh2_authconn_crstate
;
675 void *do_ssh_init_state
;
676 void *do_ssh1_login_state
;
677 void *do_ssh2_transport_state
;
678 void *do_ssh2_authconn_state
;
680 struct rdpkt1_state_tag rdpkt1_state
;
681 struct rdpkt2_state_tag rdpkt2_state
;
683 /* SSH-1 and SSH-2 use this for different things, but both use it */
684 int protocol_initial_phase_done
;
686 void (*protocol
) (Ssh ssh
, void *vin
, int inlen
,
688 struct Packet
*(*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
691 * We maintain a full _copy_ of a Config structure here, not
692 * merely a pointer to it. That way, when we're passed a new
693 * one for reconfiguration, we can check the differences and
694 * potentially reconfigure port forwardings etc in mid-session.
699 * Used to transfer data back from async callbacks.
701 void *agent_response
;
702 int agent_response_len
;
706 * The SSH connection can be set as `frozen', meaning we are
707 * not currently accepting incoming data from the network. This
708 * is slightly more serious than setting the _socket_ as
709 * frozen, because we may already have had data passed to us
710 * from the network which we need to delay processing until
711 * after the freeze is lifted, so we also need a bufchain to
715 bufchain queued_incoming_data
;
718 * Dispatch table for packet types that we may have to deal
721 handler_fn_t packet_dispatch
[256];
724 * Queues of one-off handler functions for success/failure
725 * indications from a request.
727 struct queued_handler
*qhead
, *qtail
;
730 * This module deals with sending keepalives.
735 * Track incoming and outgoing data sizes and time, for
738 unsigned long incoming_data_size
, outgoing_data_size
, deferred_data_size
;
739 unsigned long max_data_size
;
741 long next_rekey
, last_rekey
;
742 char *deferred_rekey_reason
; /* points to STATIC string; don't free */
745 #define logevent(s) logevent(ssh->frontend, s)
747 /* logevent, only printf-formatted. */
748 static void logeventf(Ssh ssh
, const char *fmt
, ...)
754 buf
= dupvprintf(fmt
, ap
);
760 #define bombout(msg) \
762 char *text = dupprintf msg; \
763 ssh_do_close(ssh, FALSE); \
765 connection_fatal(ssh->frontend, "%s", text); \
769 /* Functions to leave bits out of the SSH packet log file. */
771 static void dont_log_password(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
773 if (ssh
->cfg
.logomitpass
)
774 pkt
->logmode
= blanktype
;
777 static void dont_log_data(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
779 if (ssh
->cfg
.logomitdata
)
780 pkt
->logmode
= blanktype
;
783 static void end_log_omission(Ssh ssh
, struct Packet
*pkt
)
785 pkt
->logmode
= PKTLOG_EMIT
;
788 static int ssh_channelcmp(void *av
, void *bv
)
790 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
791 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
792 if (a
->localid
< b
->localid
)
794 if (a
->localid
> b
->localid
)
798 static int ssh_channelfind(void *av
, void *bv
)
800 unsigned *a
= (unsigned *) av
;
801 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
809 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
811 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
812 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
814 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
815 return i
< 0 ?
-1 : +1;
816 if (a
->dport
> b
->dport
)
818 if (a
->dport
< b
->dport
)
823 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
825 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
826 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
828 if (a
->sport
> b
->sport
)
830 if (a
->sport
< b
->sport
)
836 * Special form of strcmp which can cope with NULL inputs. NULL is
837 * defined to sort before even the empty string.
839 static int nullstrcmp(const char *a
, const char *b
)
841 if (a
== NULL
&& b
== NULL
)
850 static int ssh_portcmp(void *av
, void *bv
)
852 struct ssh_portfwd
*a
= (struct ssh_portfwd
*) av
;
853 struct ssh_portfwd
*b
= (struct ssh_portfwd
*) bv
;
855 if (a
->type
> b
->type
)
857 if (a
->type
< b
->type
)
859 if (a
->addressfamily
> b
->addressfamily
)
861 if (a
->addressfamily
< b
->addressfamily
)
863 if ( (i
= nullstrcmp(a
->saddr
, b
->saddr
)) != 0)
864 return i
< 0 ?
-1 : +1;
865 if (a
->sport
> b
->sport
)
867 if (a
->sport
< b
->sport
)
869 if (a
->type
!= 'D') {
870 if ( (i
= nullstrcmp(a
->daddr
, b
->daddr
)) != 0)
871 return i
< 0 ?
-1 : +1;
872 if (a
->dport
> b
->dport
)
874 if (a
->dport
< b
->dport
)
880 static int alloc_channel_id(Ssh ssh
)
882 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
883 unsigned low
, high
, mid
;
885 struct ssh_channel
*c
;
888 * First-fit allocation of channel numbers: always pick the
889 * lowest unused one. To do this, binary-search using the
890 * counted B-tree to find the largest channel ID which is in a
891 * contiguous sequence from the beginning. (Precisely
892 * everything in that sequence must have ID equal to its tree
893 * index plus CHANNEL_NUMBER_OFFSET.)
895 tsize
= count234(ssh
->channels
);
899 while (high
- low
> 1) {
900 mid
= (high
+ low
) / 2;
901 c
= index234(ssh
->channels
, mid
);
902 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
903 low
= mid
; /* this one is fine */
905 high
= mid
; /* this one is past it */
908 * Now low points to either -1, or the tree index of the
909 * largest ID in the initial sequence.
912 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
913 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
915 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
918 static void c_write(Ssh ssh
, const char *buf
, int len
)
920 if ((flags
& FLAG_STDERR
)) {
922 for (i
= 0; i
< len
; i
++)
924 fputc(buf
[i
], stderr
);
927 from_backend(ssh
->frontend
, 1, buf
, len
);
930 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
933 for (i
= 0; i
< len
; i
++) {
935 c_write(ssh
, "\r\n", 2);
936 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
937 c_write(ssh
, buf
+ i
, 1);
941 static void c_write_str(Ssh ssh
, const char *buf
)
943 c_write(ssh
, buf
, strlen(buf
));
946 static void ssh_free_packet(struct Packet
*pkt
)
951 static struct Packet
*ssh_new_packet(void)
953 struct Packet
*pkt
= snew(struct Packet
);
955 pkt
->body
= pkt
->data
= NULL
;
957 pkt
->logmode
= PKTLOG_EMIT
;
965 * Collect incoming data in the incoming packet buffer.
966 * Decipher and verify the packet when it is completely read.
967 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
968 * Update the *data and *datalen variables.
969 * Return a Packet structure when a packet is completed.
971 static struct Packet
*ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
973 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
975 crBegin(ssh
->ssh1_rdpkt_crstate
);
977 st
->pktin
= ssh_new_packet();
980 st
->pktin
->length
= 0;
982 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
983 while ((*datalen
) == 0)
985 st
->len
= (st
->len
<< 8) + **data
;
986 (*data
)++, (*datalen
)--;
989 st
->pad
= 8 - (st
->len
% 8);
990 st
->biglen
= st
->len
+ st
->pad
;
991 st
->pktin
->length
= st
->len
- 5;
993 if (st
->biglen
< 0) {
994 bombout(("Extremely large packet length from server suggests"
995 " data stream corruption"));
996 ssh_free_packet(st
->pktin
);
1000 st
->pktin
->maxlen
= st
->biglen
;
1001 st
->pktin
->data
= snewn(st
->biglen
+ APIEXTRA
, unsigned char);
1003 st
->to_read
= st
->biglen
;
1004 st
->p
= st
->pktin
->data
;
1005 while (st
->to_read
> 0) {
1006 st
->chunk
= st
->to_read
;
1007 while ((*datalen
) == 0)
1009 if (st
->chunk
> (*datalen
))
1010 st
->chunk
= (*datalen
);
1011 memcpy(st
->p
, *data
, st
->chunk
);
1013 *datalen
-= st
->chunk
;
1015 st
->to_read
-= st
->chunk
;
1018 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, st
->pktin
->data
,
1019 st
->biglen
, NULL
)) {
1020 bombout(("Network attack (CRC compensation) detected!"));
1021 ssh_free_packet(st
->pktin
);
1026 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, st
->pktin
->data
, st
->biglen
);
1028 st
->realcrc
= crc32_compute(st
->pktin
->data
, st
->biglen
- 4);
1029 st
->gotcrc
= GET_32BIT(st
->pktin
->data
+ st
->biglen
- 4);
1030 if (st
->gotcrc
!= st
->realcrc
) {
1031 bombout(("Incorrect CRC received on packet"));
1032 ssh_free_packet(st
->pktin
);
1036 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1037 st
->pktin
->savedpos
= 0;
1039 if (ssh
->v1_compressing
) {
1040 unsigned char *decompblk
;
1042 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
1043 st
->pktin
->body
- 1, st
->pktin
->length
+ 1,
1044 &decompblk
, &decomplen
)) {
1045 bombout(("Zlib decompression encountered invalid data"));
1046 ssh_free_packet(st
->pktin
);
1050 if (st
->pktin
->maxlen
< st
->pad
+ decomplen
) {
1051 st
->pktin
->maxlen
= st
->pad
+ decomplen
;
1052 st
->pktin
->data
= sresize(st
->pktin
->data
,
1053 st
->pktin
->maxlen
+ APIEXTRA
,
1055 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1058 memcpy(st
->pktin
->body
- 1, decompblk
, decomplen
);
1060 st
->pktin
->length
= decomplen
- 1;
1063 st
->pktin
->type
= st
->pktin
->body
[-1];
1066 * Log incoming packet, possibly omitting sensitive fields.
1070 struct logblank_t blank
;
1071 if (ssh
->cfg
.logomitdata
) {
1072 int do_blank
= FALSE
, blank_prefix
= 0;
1073 /* "Session data" packets - omit the data field */
1074 if ((st
->pktin
->type
== SSH1_SMSG_STDOUT_DATA
) ||
1075 (st
->pktin
->type
== SSH1_SMSG_STDERR_DATA
)) {
1076 do_blank
= TRUE
; blank_prefix
= 0;
1077 } else if (st
->pktin
->type
== SSH1_MSG_CHANNEL_DATA
) {
1078 do_blank
= TRUE
; blank_prefix
= 4;
1081 blank
.offset
= blank_prefix
;
1082 blank
.len
= st
->pktin
->length
;
1083 blank
.type
= PKTLOG_OMIT
;
1087 log_packet(ssh
->logctx
,
1088 PKT_INCOMING
, st
->pktin
->type
,
1089 ssh1_pkt_type(st
->pktin
->type
),
1090 st
->pktin
->body
, st
->pktin
->length
,
1094 crFinish(st
->pktin
);
1097 static struct Packet
*ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1099 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1101 crBegin(ssh
->ssh2_rdpkt_crstate
);
1103 st
->pktin
= ssh_new_packet();
1105 st
->pktin
->type
= 0;
1106 st
->pktin
->length
= 0;
1108 st
->cipherblk
= ssh
->sccipher
->blksize
;
1111 if (st
->cipherblk
< 8)
1114 st
->pktin
->data
= snewn(st
->cipherblk
+ APIEXTRA
, unsigned char);
1117 * Acquire and decrypt the first block of the packet. This will
1118 * contain the length and padding details.
1120 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1121 while ((*datalen
) == 0)
1123 st
->pktin
->data
[st
->i
] = *(*data
)++;
1128 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1129 st
->pktin
->data
, st
->cipherblk
);
1132 * Now get the length and padding figures.
1134 st
->len
= GET_32BIT(st
->pktin
->data
);
1135 st
->pad
= st
->pktin
->data
[4];
1138 * _Completely_ silly lengths should be stomped on before they
1139 * do us any more damage.
1141 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
1142 bombout(("Incoming packet was garbled on decryption"));
1143 ssh_free_packet(st
->pktin
);
1148 * This enables us to deduce the payload length.
1150 st
->payload
= st
->len
- st
->pad
- 1;
1152 st
->pktin
->length
= st
->payload
+ 5;
1155 * So now we can work out the total packet length.
1157 st
->packetlen
= st
->len
+ 4;
1158 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1161 * Allocate memory for the rest of the packet.
1163 st
->pktin
->maxlen
= st
->packetlen
+ st
->maclen
;
1164 st
->pktin
->data
= sresize(st
->pktin
->data
,
1165 st
->pktin
->maxlen
+ APIEXTRA
,
1169 * Read and decrypt the remainder of the packet.
1171 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1173 while ((*datalen
) == 0)
1175 st
->pktin
->data
[st
->i
] = *(*data
)++;
1178 /* Decrypt everything _except_ the MAC. */
1180 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1181 st
->pktin
->data
+ st
->cipherblk
,
1182 st
->packetlen
- st
->cipherblk
);
1184 st
->pktin
->encrypted_len
= st
->packetlen
;
1190 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, st
->pktin
->data
, st
->len
+ 4,
1191 st
->incoming_sequence
)) {
1192 bombout(("Incorrect MAC received on packet"));
1193 ssh_free_packet(st
->pktin
);
1197 st
->pktin
->sequence
= st
->incoming_sequence
++;
1200 * Decompress packet payload.
1203 unsigned char *newpayload
;
1206 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1207 st
->pktin
->data
+ 5, st
->pktin
->length
- 5,
1208 &newpayload
, &newlen
)) {
1209 if (st
->pktin
->maxlen
< newlen
+ 5) {
1210 st
->pktin
->maxlen
= newlen
+ 5;
1211 st
->pktin
->data
= sresize(st
->pktin
->data
,
1212 st
->pktin
->maxlen
+ APIEXTRA
,
1215 st
->pktin
->length
= 5 + newlen
;
1216 memcpy(st
->pktin
->data
+ 5, newpayload
, newlen
);
1221 st
->pktin
->savedpos
= 6;
1222 st
->pktin
->body
= st
->pktin
->data
;
1223 st
->pktin
->type
= st
->pktin
->data
[5];
1226 * Log incoming packet, possibly omitting sensitive fields.
1230 struct logblank_t blank
;
1231 if (ssh
->cfg
.logomitdata
) {
1232 int do_blank
= FALSE
, blank_prefix
= 0;
1233 /* "Session data" packets - omit the data field */
1234 if (st
->pktin
->type
== SSH2_MSG_CHANNEL_DATA
) {
1235 do_blank
= TRUE
; blank_prefix
= 4;
1236 } else if (st
->pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1237 do_blank
= TRUE
; blank_prefix
= 8;
1240 blank
.offset
= blank_prefix
;
1241 blank
.len
= (st
->pktin
->length
-6) - blank_prefix
;
1242 blank
.type
= PKTLOG_OMIT
;
1246 log_packet(ssh
->logctx
, PKT_INCOMING
, st
->pktin
->type
,
1247 ssh2_pkt_type(ssh
->pkt_ctx
, st
->pktin
->type
),
1248 st
->pktin
->data
+6, st
->pktin
->length
-6,
1252 crFinish(st
->pktin
);
1255 static int s_wrpkt_prepare(Ssh ssh
, struct Packet
*pkt
, int *offset_p
)
1257 int pad
, biglen
, i
, pktoffs
;
1261 * XXX various versions of SC (including 8.8.4) screw up the
1262 * register allocation in this function and use the same register
1263 * (D6) for len and as a temporary, with predictable results. The
1264 * following sledgehammer prevents this.
1271 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[12],
1272 ssh1_pkt_type(pkt
->data
[12]),
1273 pkt
->body
, pkt
->length
- (pkt
->body
- pkt
->data
),
1274 pkt
->nblanks
, pkt
->blanks
);
1275 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1278 if (ssh
->v1_compressing
) {
1279 unsigned char *compblk
;
1281 zlib_compress_block(ssh
->cs_comp_ctx
,
1282 pkt
->data
+ 12, pkt
->length
- 12,
1283 &compblk
, &complen
);
1284 memcpy(pkt
->data
+ 12, compblk
, complen
);
1286 pkt
->length
= complen
+ 12;
1289 ssh_pkt_ensure(pkt
, pkt
->length
+ 4); /* space for CRC */
1291 len
= pkt
->length
- 4 - 8; /* len(type+data+CRC) */
1292 pad
= 8 - (len
% 8);
1294 biglen
= len
+ pad
; /* len(padding+type+data+CRC) */
1296 for (i
= pktoffs
; i
< 4+8; i
++)
1297 pkt
->data
[i
] = random_byte();
1298 crc
= crc32_compute(pkt
->data
+ pktoffs
+ 4, biglen
- 4); /* all ex len */
1299 PUT_32BIT(pkt
->data
+ pktoffs
+ 4 + biglen
- 4, crc
);
1300 PUT_32BIT(pkt
->data
+ pktoffs
, len
);
1303 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
,
1304 pkt
->data
+ pktoffs
+ 4, biglen
);
1306 if (offset_p
) *offset_p
= pktoffs
;
1307 return biglen
+ 4; /* len(length+padding+type+data+CRC) */
1310 static void s_wrpkt(Ssh ssh
, struct Packet
*pkt
)
1312 int len
, backlog
, offset
;
1313 len
= s_wrpkt_prepare(ssh
, pkt
, &offset
);
1314 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
+ offset
, len
);
1315 if (backlog
> SSH_MAX_BACKLOG
)
1316 ssh_throttle_all(ssh
, 1, backlog
);
1317 ssh_free_packet(pkt
);
1320 static void s_wrpkt_defer(Ssh ssh
, struct Packet
*pkt
)
1323 len
= s_wrpkt_prepare(ssh
, pkt
, &offset
);
1324 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1325 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1326 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1330 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
,
1331 pkt
->data
+ offset
, len
);
1332 ssh
->deferred_len
+= len
;
1333 ssh_free_packet(pkt
);
1337 * Construct a SSH-1 packet with the specified contents.
1338 * (This all-at-once interface used to be the only one, but now SSH-1
1339 * packets can also be constructed incrementally.)
1341 static struct Packet
*construct_packet(Ssh ssh
, int pkttype
, va_list ap
)
1347 pkt
= ssh1_pkt_init(pkttype
);
1349 while ((argtype
= va_arg(ap
, int)) != PKT_END
) {
1350 unsigned char *argp
, argchar
;
1351 unsigned long argint
;
1354 /* Actual fields in the packet */
1356 argint
= va_arg(ap
, int);
1357 ssh_pkt_adduint32(pkt
, argint
);
1360 argchar
= (unsigned char) va_arg(ap
, int);
1361 ssh_pkt_addbyte(pkt
, argchar
);
1364 argp
= va_arg(ap
, unsigned char *);
1365 arglen
= va_arg(ap
, int);
1366 ssh_pkt_adddata(pkt
, argp
, arglen
);
1369 argp
= va_arg(ap
, unsigned char *);
1370 ssh_pkt_addstring(pkt
, argp
);
1373 bn
= va_arg(ap
, Bignum
);
1374 ssh1_pkt_addmp(pkt
, bn
);
1376 /* Tokens for modifications to packet logging */
1378 dont_log_password(ssh
, pkt
, PKTLOG_BLANK
);
1381 dont_log_data(ssh
, pkt
, PKTLOG_OMIT
);
1384 end_log_omission(ssh
, pkt
);
1392 static void send_packet(Ssh ssh
, int pkttype
, ...)
1396 va_start(ap
, pkttype
);
1397 pkt
= construct_packet(ssh
, pkttype
, ap
);
1402 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1406 va_start(ap
, pkttype
);
1407 pkt
= construct_packet(ssh
, pkttype
, ap
);
1409 s_wrpkt_defer(ssh
, pkt
);
1412 static int ssh_versioncmp(char *a
, char *b
)
1415 unsigned long av
, bv
;
1417 av
= strtoul(a
, &ae
, 10);
1418 bv
= strtoul(b
, &be
, 10);
1420 return (av
< bv ?
-1 : +1);
1425 av
= strtoul(ae
, &ae
, 10);
1426 bv
= strtoul(be
, &be
, 10);
1428 return (av
< bv ?
-1 : +1);
1433 * Utility routines for putting an SSH-protocol `string' and
1434 * `uint32' into a SHA state.
1436 static void sha_string(SHA_State
* s
, void *str
, int len
)
1438 unsigned char lenblk
[4];
1439 PUT_32BIT(lenblk
, len
);
1440 SHA_Bytes(s
, lenblk
, 4);
1441 SHA_Bytes(s
, str
, len
);
1444 static void sha_uint32(SHA_State
* s
, unsigned i
)
1446 unsigned char intblk
[4];
1447 PUT_32BIT(intblk
, i
);
1448 SHA_Bytes(s
, intblk
, 4);
1452 * Packet construction functions. Mostly shared between SSH-1 and SSH-2.
1454 static void ssh_pkt_ensure(struct Packet
*pkt
, int length
)
1456 if (pkt
->maxlen
< length
) {
1457 unsigned char *body
= pkt
->body
;
1458 int offset
= body ? pkt
->data
- body
: 0;
1459 pkt
->maxlen
= length
+ 256;
1460 pkt
->data
= sresize(pkt
->data
, pkt
->maxlen
+ APIEXTRA
, unsigned char);
1461 if (body
) pkt
->body
= pkt
->data
+ offset
;
1464 static void ssh_pkt_adddata(struct Packet
*pkt
, void *data
, int len
)
1466 if (pkt
->logmode
!= PKTLOG_EMIT
) {
1468 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
, struct logblank_t
);
1470 pkt
->blanks
[pkt
->nblanks
-1].offset
= pkt
->length
-
1471 (pkt
->body
- pkt
->data
);
1472 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1473 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1476 ssh_pkt_ensure(pkt
, pkt
->length
);
1477 memcpy(pkt
->data
+ pkt
->length
- len
, data
, len
);
1479 static void ssh_pkt_addbyte(struct Packet
*pkt
, unsigned char byte
)
1481 ssh_pkt_adddata(pkt
, &byte
, 1);
1483 static void ssh2_pkt_addbool(struct Packet
*pkt
, unsigned char value
)
1485 ssh_pkt_adddata(pkt
, &value
, 1);
1487 static void ssh_pkt_adduint32(struct Packet
*pkt
, unsigned long value
)
1490 PUT_32BIT(x
, value
);
1491 ssh_pkt_adddata(pkt
, x
, 4);
1493 static void ssh_pkt_addstring_start(struct Packet
*pkt
)
1495 ssh_pkt_adduint32(pkt
, 0);
1496 pkt
->savedpos
= pkt
->length
;
1498 static void ssh_pkt_addstring_str(struct Packet
*pkt
, char *data
)
1500 ssh_pkt_adddata(pkt
, data
, strlen(data
));
1501 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1503 static void ssh_pkt_addstring_data(struct Packet
*pkt
, char *data
, int len
)
1505 ssh_pkt_adddata(pkt
, data
, len
);
1506 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1508 static void ssh_pkt_addstring(struct Packet
*pkt
, char *data
)
1510 ssh_pkt_addstring_start(pkt
);
1511 ssh_pkt_addstring_str(pkt
, data
);
1513 static void ssh1_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1515 int len
= ssh1_bignum_length(b
);
1516 unsigned char *data
= snewn(len
, char);
1517 (void) ssh1_write_bignum(data
, b
);
1518 ssh_pkt_adddata(pkt
, data
, len
);
1521 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1524 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1525 p
= snewn(n
+ 1, unsigned char);
1527 fatalbox("out of memory");
1529 for (i
= 1; i
<= n
; i
++)
1530 p
[i
] = bignum_byte(b
, n
- i
);
1532 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1534 memmove(p
, p
+ i
, n
+ 1 - i
);
1538 static void ssh2_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1542 p
= ssh2_mpint_fmt(b
, &len
);
1543 ssh_pkt_addstring_start(pkt
);
1544 ssh_pkt_addstring_data(pkt
, (char *)p
, len
);
1548 static struct Packet
*ssh1_pkt_init(int pkt_type
)
1550 struct Packet
*pkt
= ssh_new_packet();
1551 pkt
->length
= 4 + 8; /* space for length + max padding */
1552 ssh_pkt_addbyte(pkt
, pkt_type
);
1553 pkt
->body
= pkt
->data
+ pkt
->length
;
1557 /* For legacy code (SSH-1 and -2 packet construction used to be separate) */
1558 #define ssh2_pkt_ensure(pkt, length) ssh_pkt_ensure(pkt, length)
1559 #define ssh2_pkt_adddata(pkt, data, len) ssh_pkt_adddata(pkt, data, len)
1560 #define ssh2_pkt_addbyte(pkt, byte) ssh_pkt_addbyte(pkt, byte)
1561 #define ssh2_pkt_adduint32(pkt, value) ssh_pkt_adduint32(pkt, value)
1562 #define ssh2_pkt_addstring_start(pkt) ssh_pkt_addstring_start(pkt)
1563 #define ssh2_pkt_addstring_str(pkt, data) ssh_pkt_addstring_str(pkt, data)
1564 #define ssh2_pkt_addstring_data(pkt, data, len) ssh_pkt_addstring_data(pkt, data, len)
1565 #define ssh2_pkt_addstring(pkt, data) ssh_pkt_addstring(pkt, data)
1567 static struct Packet
*ssh2_pkt_init(int pkt_type
)
1569 struct Packet
*pkt
= ssh_new_packet();
1572 ssh_pkt_addbyte(pkt
, (unsigned char) pkt_type
);
1573 pkt
->body
= pkt
->data
+ pkt
->length
;
1578 * Construct an SSH-2 final-form packet: compress it, encrypt it,
1579 * put the MAC on it. Final packet, ready to be sent, is stored in
1580 * pkt->data. Total length is returned.
1582 static int ssh2_pkt_construct(Ssh ssh
, struct Packet
*pkt
)
1584 int cipherblk
, maclen
, padding
, i
;
1587 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[5],
1588 ssh2_pkt_type(ssh
->pkt_ctx
, pkt
->data
[5]),
1589 pkt
->body
, pkt
->length
- (pkt
->body
- pkt
->data
),
1590 pkt
->nblanks
, pkt
->blanks
);
1591 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1595 * Compress packet payload.
1598 unsigned char *newpayload
;
1601 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, pkt
->data
+ 5,
1603 &newpayload
, &newlen
)) {
1605 ssh2_pkt_adddata(pkt
, newpayload
, newlen
);
1611 * Add padding. At least four bytes, and must also bring total
1612 * length (minus MAC) up to a multiple of the block size.
1613 * If pkt->forcepad is set, make sure the packet is at least that size
1616 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1617 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1619 if (pkt
->length
+ padding
< pkt
->forcepad
)
1620 padding
= pkt
->forcepad
- pkt
->length
;
1622 (cipherblk
- (pkt
->length
+ padding
) % cipherblk
) % cipherblk
;
1623 assert(padding
<= 255);
1624 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1625 ssh2_pkt_ensure(pkt
, pkt
->length
+ padding
+ maclen
);
1626 pkt
->data
[4] = padding
;
1627 for (i
= 0; i
< padding
; i
++)
1628 pkt
->data
[pkt
->length
+ i
] = random_byte();
1629 PUT_32BIT(pkt
->data
, pkt
->length
+ padding
- 4);
1631 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, pkt
->data
,
1632 pkt
->length
+ padding
,
1633 ssh
->v2_outgoing_sequence
);
1634 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1637 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1638 pkt
->data
, pkt
->length
+ padding
);
1640 pkt
->encrypted_len
= pkt
->length
+ padding
;
1642 /* Ready-to-send packet starts at pkt->data. We return length. */
1643 return pkt
->length
+ padding
+ maclen
;
1647 * Routines called from the main SSH code to send packets. There
1648 * are quite a few of these, because we have two separate
1649 * mechanisms for delaying the sending of packets:
1651 * - In order to send an IGNORE message and a password message in
1652 * a single fixed-length blob, we require the ability to
1653 * concatenate the encrypted forms of those two packets _into_ a
1654 * single blob and then pass it to our <network.h> transport
1655 * layer in one go. Hence, there's a deferment mechanism which
1656 * works after packet encryption.
1658 * - In order to avoid sending any connection-layer messages
1659 * during repeat key exchange, we have to queue up any such
1660 * outgoing messages _before_ they are encrypted (and in
1661 * particular before they're allocated sequence numbers), and
1662 * then send them once we've finished.
1664 * I call these mechanisms `defer' and `queue' respectively, so as
1665 * to distinguish them reasonably easily.
1667 * The functions send_noqueue() and defer_noqueue() free the packet
1668 * structure they are passed. Every outgoing packet goes through
1669 * precisely one of these functions in its life; packets passed to
1670 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1671 * these or get queued, and then when the queue is later emptied
1672 * the packets are all passed to defer_noqueue().
1676 * Send an SSH-2 packet immediately, without queuing or deferring.
1678 static void ssh2_pkt_send_noqueue(Ssh ssh
, struct Packet
*pkt
)
1682 len
= ssh2_pkt_construct(ssh
, pkt
);
1683 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1684 if (backlog
> SSH_MAX_BACKLOG
)
1685 ssh_throttle_all(ssh
, 1, backlog
);
1687 ssh
->outgoing_data_size
+= pkt
->encrypted_len
;
1688 if (!ssh
->kex_in_progress
&&
1689 ssh
->max_data_size
!= 0 &&
1690 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1691 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1693 ssh_free_packet(pkt
);
1697 * Defer an SSH-2 packet.
1699 static void ssh2_pkt_defer_noqueue(Ssh ssh
, struct Packet
*pkt
)
1701 int len
= ssh2_pkt_construct(ssh
, pkt
);
1702 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1703 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1704 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1708 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1709 ssh
->deferred_len
+= len
;
1710 ssh
->deferred_data_size
+= pkt
->encrypted_len
;
1711 ssh_free_packet(pkt
);
1715 * Queue an SSH-2 packet.
1717 static void ssh2_pkt_queue(Ssh ssh
, struct Packet
*pkt
)
1719 assert(ssh
->queueing
);
1721 if (ssh
->queuelen
>= ssh
->queuesize
) {
1722 ssh
->queuesize
= ssh
->queuelen
+ 32;
1723 ssh
->queue
= sresize(ssh
->queue
, ssh
->queuesize
, struct Packet
*);
1726 ssh
->queue
[ssh
->queuelen
++] = pkt
;
1730 * Either queue or send a packet, depending on whether queueing is
1733 static void ssh2_pkt_send(Ssh ssh
, struct Packet
*pkt
)
1736 ssh2_pkt_queue(ssh
, pkt
);
1738 ssh2_pkt_send_noqueue(ssh
, pkt
);
1743 * Either queue or defer a packet, depending on whether queueing is
1746 static void ssh2_pkt_defer(Ssh ssh
, struct Packet
*pkt
)
1749 ssh2_pkt_queue(ssh
, pkt
);
1751 ssh2_pkt_defer_noqueue(ssh
, pkt
);
1756 * Send the whole deferred data block constructed by
1757 * ssh2_pkt_defer() or SSH-1's defer_packet().
1759 * The expected use of the defer mechanism is that you call
1760 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1761 * not currently queueing, this simply sets up deferred_send_data
1762 * and then sends it. If we _are_ currently queueing, the calls to
1763 * ssh2_pkt_defer() put the deferred packets on to the queue
1764 * instead, and therefore ssh_pkt_defersend() has no deferred data
1765 * to send. Hence, there's no need to make it conditional on
1768 static void ssh_pkt_defersend(Ssh ssh
)
1771 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1773 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1774 sfree(ssh
->deferred_send_data
);
1775 ssh
->deferred_send_data
= NULL
;
1776 if (backlog
> SSH_MAX_BACKLOG
)
1777 ssh_throttle_all(ssh
, 1, backlog
);
1779 ssh
->outgoing_data_size
+= ssh
->deferred_data_size
;
1780 if (!ssh
->kex_in_progress
&&
1781 ssh
->max_data_size
!= 0 &&
1782 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1783 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1784 ssh
->deferred_data_size
= 0;
1788 * Send all queued SSH-2 packets. We send them by means of
1789 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1790 * packets that needed to be lumped together.
1792 static void ssh2_pkt_queuesend(Ssh ssh
)
1796 assert(!ssh
->queueing
);
1798 for (i
= 0; i
< ssh
->queuelen
; i
++)
1799 ssh2_pkt_defer_noqueue(ssh
, ssh
->queue
[i
]);
1802 ssh_pkt_defersend(ssh
);
1806 void bndebug(char *string
, Bignum b
)
1810 p
= ssh2_mpint_fmt(b
, &len
);
1811 debug(("%s", string
));
1812 for (i
= 0; i
< len
; i
++)
1813 debug((" %02x", p
[i
]));
1819 static void sha_mpint(SHA_State
* s
, Bignum b
)
1823 p
= ssh2_mpint_fmt(b
, &len
);
1824 sha_string(s
, p
, len
);
1829 * Packet decode functions for both SSH-1 and SSH-2.
1831 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
)
1833 unsigned long value
;
1834 if (pkt
->length
- pkt
->savedpos
< 4)
1835 return 0; /* arrgh, no way to decline (FIXME?) */
1836 value
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1840 static int ssh2_pkt_getbool(struct Packet
*pkt
)
1842 unsigned long value
;
1843 if (pkt
->length
- pkt
->savedpos
< 1)
1844 return 0; /* arrgh, no way to decline (FIXME?) */
1845 value
= pkt
->body
[pkt
->savedpos
] != 0;
1849 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
)
1854 if (pkt
->length
- pkt
->savedpos
< 4)
1856 len
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1861 if (pkt
->length
- pkt
->savedpos
< *length
)
1863 *p
= (char *)(pkt
->body
+ pkt
->savedpos
);
1864 pkt
->savedpos
+= *length
;
1866 static void *ssh_pkt_getdata(struct Packet
*pkt
, int length
)
1868 if (pkt
->length
- pkt
->savedpos
< length
)
1870 pkt
->savedpos
+= length
;
1871 return pkt
->body
+ (pkt
->savedpos
- length
);
1873 static int ssh1_pkt_getrsakey(struct Packet
*pkt
, struct RSAKey
*key
,
1874 unsigned char **keystr
)
1878 j
= makekey(pkt
->body
+ pkt
->savedpos
,
1879 pkt
->length
- pkt
->savedpos
,
1886 assert(pkt
->savedpos
< pkt
->length
);
1890 static Bignum
ssh1_pkt_getmp(struct Packet
*pkt
)
1895 j
= ssh1_read_bignum(pkt
->body
+ pkt
->savedpos
,
1896 pkt
->length
- pkt
->savedpos
, &b
);
1904 static Bignum
ssh2_pkt_getmp(struct Packet
*pkt
)
1910 ssh_pkt_getstring(pkt
, &p
, &length
);
1915 b
= bignum_from_bytes((unsigned char *)p
, length
);
1920 * Helper function to add an SSH-2 signature blob to a packet.
1921 * Expects to be shown the public key blob as well as the signature
1922 * blob. Normally works just like ssh2_pkt_addstring, but will
1923 * fiddle with the signature packet if necessary for
1924 * BUG_SSH2_RSA_PADDING.
1926 static void ssh2_add_sigblob(Ssh ssh
, struct Packet
*pkt
,
1927 void *pkblob_v
, int pkblob_len
,
1928 void *sigblob_v
, int sigblob_len
)
1930 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1931 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1933 /* dmemdump(pkblob, pkblob_len); */
1934 /* dmemdump(sigblob, sigblob_len); */
1937 * See if this is in fact an ssh-rsa signature and a buggy
1938 * server; otherwise we can just do this the easy way.
1940 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1941 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1942 int pos
, len
, siglen
;
1945 * Find the byte length of the modulus.
1948 pos
= 4+7; /* skip over "ssh-rsa" */
1949 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1950 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
1951 pos
+= 4; /* find modulus itself */
1952 while (len
> 0 && pkblob
[pos
] == 0)
1954 /* debug(("modulus length is %d\n", len)); */
1957 * Now find the signature integer.
1959 pos
= 4+7; /* skip over "ssh-rsa" */
1960 siglen
= GET_32BIT(sigblob
+pos
);
1961 /* debug(("signature length is %d\n", siglen)); */
1963 if (len
!= siglen
) {
1964 unsigned char newlen
[4];
1965 ssh2_pkt_addstring_start(pkt
);
1966 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, pos
);
1967 /* dmemdump(sigblob, pos); */
1968 pos
+= 4; /* point to start of actual sig */
1969 PUT_32BIT(newlen
, len
);
1970 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 4);
1971 /* dmemdump(newlen, 4); */
1973 while (len
-- > siglen
) {
1974 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 1);
1975 /* dmemdump(newlen, 1); */
1977 ssh2_pkt_addstring_data(pkt
, (char *)(sigblob
+pos
), siglen
);
1978 /* dmemdump(sigblob+pos, siglen); */
1982 /* Otherwise fall through and do it the easy way. */
1985 ssh2_pkt_addstring_start(pkt
);
1986 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, sigblob_len
);
1990 * Examine the remote side's version string and compare it against
1991 * a list of known buggy implementations.
1993 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
1995 char *imp
; /* pointer to implementation part */
1997 imp
+= strcspn(imp
, "-");
1999 imp
+= strcspn(imp
, "-");
2002 ssh
->remote_bugs
= 0;
2004 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
2005 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
2006 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
2007 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
2008 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
2009 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
2011 * These versions don't support SSH1_MSG_IGNORE, so we have
2012 * to use a different defence against password length
2015 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
2016 logevent("We believe remote version has SSH-1 ignore bug");
2019 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
2020 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
2021 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
2023 * These versions need a plain password sent; they can't
2024 * handle having a null and a random length of data after
2027 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
2028 logevent("We believe remote version needs a plain SSH-1 password");
2031 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
2032 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
2033 (!strcmp(imp
, "Cisco-1.25")))) {
2035 * These versions apparently have no clue whatever about
2036 * RSA authentication and will panic and die if they see
2037 * an AUTH_RSA message.
2039 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
2040 logevent("We believe remote version can't handle SSH-1 RSA authentication");
2043 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
2044 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
2045 !wc_match("* VShell", imp
) &&
2046 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
2047 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
2048 wc_match("2.1 *", imp
)))) {
2050 * These versions have the HMAC bug.
2052 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
2053 logevent("We believe remote version has SSH-2 HMAC bug");
2056 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2057 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2058 !wc_match("* VShell", imp
) &&
2059 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2061 * These versions have the key-derivation bug (failing to
2062 * include the literal shared secret in the hashes that
2063 * generate the keys).
2065 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2066 logevent("We believe remote version has SSH-2 key-derivation bug");
2069 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2070 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2071 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2072 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2074 * These versions have the SSH-2 RSA padding bug.
2076 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2077 logevent("We believe remote version has SSH-2 RSA padding bug");
2080 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2081 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2082 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2084 * These versions have the SSH-2 session-ID bug in
2085 * public-key authentication.
2087 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2088 logevent("We believe remote version has SSH-2 public-key-session-ID bug");
2091 if (ssh
->cfg
.sshbug_rekey2
== FORCE_ON
||
2092 (ssh
->cfg
.sshbug_rekey2
== AUTO
&&
2093 (wc_match("OpenSSH_2.[0-4]*", imp
) ||
2094 wc_match("OpenSSH_2.5.[0-3]*", imp
) ||
2095 wc_match("Sun_SSH_1.0", imp
) ||
2096 wc_match("Sun_SSH_1.0.1", imp
)))) {
2098 * These versions have the SSH-2 rekey bug.
2100 ssh
->remote_bugs
|= BUG_SSH2_REKEY
;
2101 logevent("We believe remote version has SSH-2 rekey bug");
2106 * The `software version' part of an SSH version string is required
2107 * to contain no spaces or minus signs.
2109 static void ssh_fix_verstring(char *str
)
2111 /* Eat "SSH-<protoversion>-". */
2112 assert(*str
== 'S'); str
++;
2113 assert(*str
== 'S'); str
++;
2114 assert(*str
== 'H'); str
++;
2115 assert(*str
== '-'); str
++;
2116 while (*str
&& *str
!= '-') str
++;
2117 assert(*str
== '-'); str
++;
2119 /* Convert minus signs and spaces in the remaining string into
2122 if (*str
== '-' || *str
== ' ')
2128 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2130 struct do_ssh_init_state
{
2138 crState(do_ssh_init_state
);
2140 crBegin(ssh
->do_ssh_init_crstate
);
2142 /* Search for the string "SSH-" in the input. */
2145 static const int transS
[] = { 1, 2, 2, 1 };
2146 static const int transH
[] = { 0, 0, 3, 0 };
2147 static const int transminus
[] = { 0, 0, 0, -1 };
2149 s
->i
= transS
[s
->i
];
2151 s
->i
= transH
[s
->i
];
2153 s
->i
= transminus
[s
->i
];
2158 crReturn(1); /* get another character */
2162 s
->vstring
= snewn(s
->vstrsize
, char);
2163 strcpy(s
->vstring
, "SSH-");
2167 crReturn(1); /* get another char */
2168 if (s
->vslen
>= s
->vstrsize
- 1) {
2170 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2172 s
->vstring
[s
->vslen
++] = c
;
2175 s
->version
[s
->i
] = '\0';
2177 } else if (s
->i
< sizeof(s
->version
) - 1)
2178 s
->version
[s
->i
++] = c
;
2179 } else if (c
== '\012')
2183 ssh
->agentfwd_enabled
= FALSE
;
2184 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2186 s
->vstring
[s
->vslen
] = 0;
2187 s
->vstring
[strcspn(s
->vstring
, "\015\012")] = '\0';/* remove EOL chars */
2188 logeventf(ssh
, "Server version: %s", s
->vstring
);
2189 ssh_detect_bugs(ssh
, s
->vstring
);
2192 * Decide which SSH protocol version to support.
2195 /* Anything strictly below "2.0" means protocol 1 is supported. */
2196 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2197 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2198 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2200 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2201 bombout(("SSH protocol version 1 required by user but not provided by server"));
2204 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2205 bombout(("SSH protocol version 2 required by user but not provided by server"));
2212 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2214 * Construct a v2 version string.
2216 verstring
= dupprintf("SSH-2.0-%s\015\012", sshver
);
2220 * Construct a v1 version string.
2222 verstring
= dupprintf("SSH-%s-%s\012",
2223 (ssh_versioncmp(s
->version
, "1.5") <= 0 ?
2224 s
->version
: "1.5"),
2229 ssh_fix_verstring(verstring
);
2231 if (ssh
->version
== 2) {
2233 * Hash our version string and their version string.
2235 SHA_Init(&ssh
->exhashbase
);
2236 sha_string(&ssh
->exhashbase
, verstring
,
2237 strcspn(verstring
, "\015\012"));
2238 sha_string(&ssh
->exhashbase
, s
->vstring
,
2239 strcspn(s
->vstring
, "\015\012"));
2242 * Initialise SSH-2 protocol.
2244 ssh
->protocol
= ssh2_protocol
;
2245 ssh2_protocol_setup(ssh
);
2246 ssh
->s_rdpkt
= ssh2_rdpkt
;
2249 * Initialise SSH-1 protocol.
2251 ssh
->protocol
= ssh1_protocol
;
2252 ssh1_protocol_setup(ssh
);
2253 ssh
->s_rdpkt
= ssh1_rdpkt
;
2255 logeventf(ssh
, "We claim version: %.*s",
2256 strcspn(verstring
, "\015\012"), verstring
);
2257 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2261 logeventf(ssh
, "Using SSH protocol version %d", ssh
->version
);
2263 update_specials_menu(ssh
->frontend
);
2264 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2265 ssh
->pinger
= pinger_new(&ssh
->cfg
, &ssh_backend
, ssh
);
2272 static void ssh_process_incoming_data(Ssh ssh
,
2273 unsigned char **data
, int *datalen
)
2275 struct Packet
*pktin
= ssh
->s_rdpkt(ssh
, data
, datalen
);
2277 ssh
->protocol(ssh
, NULL
, 0, pktin
);
2278 ssh_free_packet(pktin
);
2282 static void ssh_queue_incoming_data(Ssh ssh
,
2283 unsigned char **data
, int *datalen
)
2285 bufchain_add(&ssh
->queued_incoming_data
, *data
, *datalen
);
2290 static void ssh_process_queued_incoming_data(Ssh ssh
)
2293 unsigned char *data
;
2296 while (!ssh
->frozen
&& bufchain_size(&ssh
->queued_incoming_data
)) {
2297 bufchain_prefix(&ssh
->queued_incoming_data
, &vdata
, &len
);
2301 while (!ssh
->frozen
&& len
> 0)
2302 ssh_process_incoming_data(ssh
, &data
, &len
);
2305 bufchain_consume(&ssh
->queued_incoming_data
, origlen
- len
);
2309 static void ssh_set_frozen(Ssh ssh
, int frozen
)
2312 sk_set_frozen(ssh
->s
, frozen
);
2313 ssh
->frozen
= frozen
;
2316 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2318 crBegin(ssh
->ssh_gotdata_crstate
);
2321 * To begin with, feed the characters one by one to the
2322 * protocol initialisation / selection function do_ssh_init().
2323 * When that returns 0, we're done with the initial greeting
2324 * exchange and can move on to packet discipline.
2327 int ret
; /* need not be kept across crReturn */
2329 crReturnV
; /* more data please */
2330 ret
= do_ssh_init(ssh
, *data
);
2338 * We emerge from that loop when the initial negotiation is
2339 * over and we have selected an s_rdpkt function. Now pass
2340 * everything to s_rdpkt, and then pass the resulting packets
2341 * to the proper protocol handler.
2347 * Process queued data if there is any.
2349 ssh_process_queued_incoming_data(ssh
);
2352 while (datalen
> 0) {
2354 ssh_queue_incoming_data(ssh
, &data
, &datalen
);
2356 ssh_process_incoming_data(ssh
, &data
, &datalen
);
2358 if (ssh
->state
== SSH_STATE_CLOSED
)
2366 static int ssh_do_close(Ssh ssh
, int notify_exit
)
2369 struct ssh_channel
*c
;
2371 ssh
->state
= SSH_STATE_CLOSED
;
2372 expire_timer_context(ssh
);
2377 notify_remote_exit(ssh
->frontend
);
2382 * Now we must shut down any port- and X-forwarded channels going
2383 * through this connection.
2385 if (ssh
->channels
) {
2386 while (NULL
!= (c
= index234(ssh
->channels
, 0))) {
2389 x11_close(c
->u
.x11
.s
);
2392 pfd_close(c
->u
.pfd
.s
);
2395 del234(ssh
->channels
, c
); /* moving next one to index 0 */
2396 if (ssh
->version
== 2)
2397 bufchain_clear(&c
->v
.v2
.outbuffer
);
2402 * Go through port-forwardings, and close any associated
2403 * listening sockets.
2405 if (ssh
->portfwds
) {
2406 struct ssh_portfwd
*pf
;
2407 while (NULL
!= (pf
= index234(ssh
->portfwds
, 0))) {
2408 /* Dispose of any listening socket. */
2410 pfd_terminate(pf
->local
);
2411 del234(ssh
->portfwds
, pf
); /* moving next one to index 0 */
2419 static void ssh_log(Plug plug
, int type
, SockAddr addr
, int port
,
2420 const char *error_msg
, int error_code
)
2422 Ssh ssh
= (Ssh
) plug
;
2423 char addrbuf
[256], *msg
;
2425 sk_getaddr(addr
, addrbuf
, lenof(addrbuf
));
2428 msg
= dupprintf("Connecting to %s port %d", addrbuf
, port
);
2430 msg
= dupprintf("Failed to connect to %s: %s", addrbuf
, error_msg
);
2436 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2439 Ssh ssh
= (Ssh
) plug
;
2440 int need_notify
= ssh_do_close(ssh
, FALSE
);
2442 if (!error_msg
&& !ssh
->close_expected
) {
2443 error_msg
= "Server unexpectedly closed network connection";
2447 notify_remote_exit(ssh
->frontend
);
2450 /* A socket error has occurred. */
2451 logevent(error_msg
);
2452 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2454 logevent("Server closed network connection");
2459 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2461 Ssh ssh
= (Ssh
) plug
;
2462 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2463 if (ssh
->state
== SSH_STATE_CLOSED
) {
2464 ssh_do_close(ssh
, TRUE
);
2470 static void ssh_sent(Plug plug
, int bufsize
)
2472 Ssh ssh
= (Ssh
) plug
;
2474 * If the send backlog on the SSH socket itself clears, we
2475 * should unthrottle the whole world if it was throttled.
2477 if (bufsize
< SSH_MAX_BACKLOG
)
2478 ssh_throttle_all(ssh
, 0, bufsize
);
2482 * Connect to specified host and port.
2483 * Returns an error message, or NULL on success.
2484 * Also places the canonical host name into `realhost'. It must be
2485 * freed by the caller.
2487 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2488 char **realhost
, int nodelay
, int keepalive
)
2490 static const struct plug_function_table fn_table
= {
2501 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2502 if (!ssh
->savedhost
)
2503 fatalbox("Out of memory");
2504 strcpy(ssh
->savedhost
, host
);
2507 port
= 22; /* default ssh port */
2508 ssh
->savedport
= port
;
2513 logeventf(ssh
, "Looking up host \"%s\"%s", host
,
2514 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV4 ?
" (IPv4)" :
2515 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV6 ?
" (IPv6)" : "")));
2516 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
,
2517 ssh
->cfg
.addressfamily
);
2518 if ((err
= sk_addr_error(addr
)) != NULL
) {
2526 ssh
->fn
= &fn_table
;
2527 ssh
->s
= new_connection(addr
, *realhost
, port
,
2528 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2529 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2531 notify_remote_exit(ssh
->frontend
);
2539 * Throttle or unthrottle the SSH connection.
2541 static void ssh1_throttle(Ssh ssh
, int adjust
)
2543 int old_count
= ssh
->v1_throttle_count
;
2544 ssh
->v1_throttle_count
+= adjust
;
2545 assert(ssh
->v1_throttle_count
>= 0);
2546 if (ssh
->v1_throttle_count
&& !old_count
) {
2547 ssh_set_frozen(ssh
, 1);
2548 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2549 ssh_set_frozen(ssh
, 0);
2554 * Throttle or unthrottle _all_ local data streams (for when sends
2555 * on the SSH connection itself back up).
2557 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2560 struct ssh_channel
*c
;
2562 if (enable
== ssh
->throttled_all
)
2564 ssh
->throttled_all
= enable
;
2565 ssh
->overall_bufsize
= bufsize
;
2568 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2570 case CHAN_MAINSESSION
:
2572 * This is treated separately, outside the switch.
2576 x11_override_throttle(c
->u
.x11
.s
, enable
);
2579 /* Agent channels require no buffer management. */
2582 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2589 * Username and password input, abstracted off into routines
2590 * reusable in several places - even between SSH-1 and SSH-2.
2593 /* Set up a username or password input loop on a given buffer. */
2594 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2596 ssh
->userpass_input_buffer
= buffer
;
2597 ssh
->userpass_input_buflen
= buflen
;
2598 ssh
->userpass_input_bufpos
= 0;
2599 ssh
->userpass_input_echo
= echo
;
2603 * Process some terminal data in the course of username/password
2604 * input. Returns >0 for success (line of input returned in
2605 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2606 * for inconclusive (keep waiting for more input please).
2608 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2613 switch (c
= *in
++) {
2616 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2617 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2622 if (ssh
->userpass_input_bufpos
> 0) {
2623 if (ssh
->userpass_input_echo
)
2624 c_write_str(ssh
, "\b \b");
2625 ssh
->userpass_input_bufpos
--;
2630 while (ssh
->userpass_input_bufpos
> 0) {
2631 if (ssh
->userpass_input_echo
)
2632 c_write_str(ssh
, "\b \b");
2633 ssh
->userpass_input_bufpos
--;
2642 * This simplistic check for printability is disabled
2643 * when we're doing password input, because some people
2644 * have control characters in their passwords.o
2646 if ((!ssh
->userpass_input_echo
||
2647 (c
>= ' ' && c
<= '~') ||
2648 ((unsigned char) c
>= 160))
2649 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2650 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2651 if (ssh
->userpass_input_echo
)
2652 c_write(ssh
, &c
, 1);
2660 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2662 Ssh ssh
= (Ssh
) sshv
;
2664 ssh
->agent_response
= reply
;
2665 ssh
->agent_response_len
= replylen
;
2667 if (ssh
->version
== 1)
2668 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2670 do_ssh2_authconn(ssh
, NULL
, -1, NULL
);
2673 static void ssh_dialog_callback(void *sshv
, int ret
)
2675 Ssh ssh
= (Ssh
) sshv
;
2677 ssh
->user_response
= ret
;
2679 if (ssh
->version
== 1)
2680 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2682 do_ssh2_transport(ssh
, NULL
, -1, NULL
);
2685 * This may have unfrozen the SSH connection, so do a
2688 ssh_process_queued_incoming_data(ssh
);
2691 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2693 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2695 void *sentreply
= reply
;
2698 /* Fake SSH_AGENT_FAILURE. */
2699 sentreply
= "\0\0\0\1\5";
2702 if (ssh
->version
== 2) {
2703 ssh2_add_channel_data(c
, sentreply
, replylen
);
2706 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2707 PKT_INT
, c
->remoteid
,
2710 PKT_DATA
, sentreply
, replylen
,
2719 * Handle the key exchange and user authentication phases.
2721 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
2722 struct Packet
*pktin
)
2725 unsigned char cookie
[8], *ptr
;
2726 struct RSAKey servkey
, hostkey
;
2727 struct MD5Context md5c
;
2728 struct do_ssh1_login_state
{
2730 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2731 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2732 int tried_publickey
, tried_agent
;
2733 int tis_auth_refused
, ccard_auth_refused
;
2734 unsigned char session_id
[16];
2737 void *publickey_blob
;
2738 int publickey_bloblen
;
2744 unsigned char request
[5], *response
, *p
;
2754 crState(do_ssh1_login_state
);
2756 crBegin(ssh
->do_ssh1_login_crstate
);
2761 if (pktin
->type
!= SSH1_SMSG_PUBLIC_KEY
) {
2762 bombout(("Public key packet not received"));
2766 logevent("Received public keys");
2768 ptr
= ssh_pkt_getdata(pktin
, 8);
2770 bombout(("SSH-1 public key packet stopped before random cookie"));
2773 memcpy(cookie
, ptr
, 8);
2775 if (!ssh1_pkt_getrsakey(pktin
, &servkey
, &s
->keystr1
) ||
2776 !ssh1_pkt_getrsakey(pktin
, &hostkey
, &s
->keystr2
)) {
2777 bombout(("Failed to read SSH-1 public keys from public key packet"));
2782 * Log the host key fingerprint.
2786 logevent("Host key fingerprint is:");
2787 strcpy(logmsg
, " ");
2788 hostkey
.comment
= NULL
;
2789 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2790 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2794 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(pktin
);
2795 s
->supported_ciphers_mask
= ssh_pkt_getuint32(pktin
);
2796 s
->supported_auths_mask
= ssh_pkt_getuint32(pktin
);
2798 ssh
->v1_local_protoflags
=
2799 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2800 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2803 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2804 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2805 MD5Update(&md5c
, cookie
, 8);
2806 MD5Final(s
->session_id
, &md5c
);
2808 for (i
= 0; i
< 32; i
++)
2809 ssh
->session_key
[i
] = random_byte();
2812 * Verify that the `bits' and `bytes' parameters match.
2814 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
2815 servkey
.bits
> servkey
.bytes
* 8) {
2816 bombout(("SSH-1 public keys were badly formatted"));
2820 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2822 s
->rsabuf
= snewn(s
->len
, unsigned char);
2824 fatalbox("Out of memory");
2827 * Verify the host key.
2831 * First format the key into a string.
2833 int len
= rsastr_len(&hostkey
);
2834 char fingerprint
[100];
2835 char *keystr
= snewn(len
, char);
2837 fatalbox("Out of memory");
2838 rsastr_fmt(keystr
, &hostkey
);
2839 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2841 ssh_set_frozen(ssh
, 1);
2842 s
->dlgret
= verify_ssh_host_key(ssh
->frontend
,
2843 ssh
->savedhost
, ssh
->savedport
,
2844 "rsa", keystr
, fingerprint
,
2845 ssh_dialog_callback
, ssh
);
2847 if (s
->dlgret
< 0) {
2851 bombout(("Unexpected data from server while waiting"
2852 " for user host key response"));
2855 } while (pktin
|| inlen
> 0);
2856 s
->dlgret
= ssh
->user_response
;
2858 ssh_set_frozen(ssh
, 0);
2860 if (s
->dlgret
== 0) {
2861 ssh
->close_expected
= TRUE
;
2862 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2867 for (i
= 0; i
< 32; i
++) {
2868 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2870 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2873 if (hostkey
.bytes
> servkey
.bytes
) {
2874 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
2876 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2878 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2880 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2883 bombout(("SSH-1 public key encryptions failed due to bad formatting"));
2887 logevent("Encrypted session key");
2890 int cipher_chosen
= 0, warn
= 0;
2891 char *cipher_string
= NULL
;
2893 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2894 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
2895 if (next_cipher
== CIPHER_WARN
) {
2896 /* If/when we choose a cipher, warn about it */
2898 } else if (next_cipher
== CIPHER_AES
) {
2899 /* XXX Probably don't need to mention this. */
2900 logevent("AES not supported in SSH-1, skipping");
2902 switch (next_cipher
) {
2903 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2904 cipher_string
= "3DES"; break;
2905 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2906 cipher_string
= "Blowfish"; break;
2907 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2908 cipher_string
= "single-DES"; break;
2910 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2914 if (!cipher_chosen
) {
2915 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2916 bombout(("Server violates SSH-1 protocol by not "
2917 "supporting 3DES encryption"));
2919 /* shouldn't happen */
2920 bombout(("No supported ciphers found"));
2924 /* Warn about chosen cipher if necessary. */
2926 ssh_set_frozen(ssh
, 1);
2927 s
->dlgret
= askalg(ssh
->frontend
, "cipher", cipher_string
,
2928 ssh_dialog_callback
, ssh
);
2929 if (s
->dlgret
< 0) {
2933 bombout(("Unexpected data from server while waiting"
2934 " for user response"));
2937 } while (pktin
|| inlen
> 0);
2938 s
->dlgret
= ssh
->user_response
;
2940 ssh_set_frozen(ssh
, 0);
2941 if (s
->dlgret
== 0) {
2942 ssh
->close_expected
= TRUE
;
2943 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2949 switch (s
->cipher_type
) {
2950 case SSH_CIPHER_3DES
:
2951 logevent("Using 3DES encryption");
2953 case SSH_CIPHER_DES
:
2954 logevent("Using single-DES encryption");
2956 case SSH_CIPHER_BLOWFISH
:
2957 logevent("Using Blowfish encryption");
2961 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
2962 PKT_CHAR
, s
->cipher_type
,
2963 PKT_DATA
, cookie
, 8,
2964 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
2965 PKT_DATA
, s
->rsabuf
, s
->len
,
2966 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
2968 logevent("Trying to enable encryption...");
2972 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2973 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
2975 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
2976 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
2977 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
2979 ssh
->crcda_ctx
= crcda_make_context();
2980 logevent("Installing CRC compensation attack detector");
2982 if (servkey
.modulus
) {
2983 sfree(servkey
.modulus
);
2984 servkey
.modulus
= NULL
;
2986 if (servkey
.exponent
) {
2987 sfree(servkey
.exponent
);
2988 servkey
.exponent
= NULL
;
2990 if (hostkey
.modulus
) {
2991 sfree(hostkey
.modulus
);
2992 hostkey
.modulus
= NULL
;
2994 if (hostkey
.exponent
) {
2995 sfree(hostkey
.exponent
);
2996 hostkey
.exponent
= NULL
;
3000 if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3001 bombout(("Encryption not successfully enabled"));
3005 logevent("Successfully started encryption");
3009 if (!*ssh
->cfg
.username
) {
3010 if (ssh_get_line
&& !ssh_getline_pw_only
) {
3011 if (!ssh_get_line("login as: ",
3012 s
->username
, sizeof(s
->username
), FALSE
)) {
3014 * get_line failed to get a username.
3017 logevent("No username provided. Abandoning session.");
3018 ssh
->close_expected
= TRUE
;
3019 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3023 int ret
; /* need not be kept over crReturn */
3024 c_write_str(ssh
, "login as: ");
3027 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
3029 crWaitUntil(!pktin
);
3030 ret
= process_userpass_input(ssh
, in
, inlen
);
3034 c_write_str(ssh
, "\r\n");
3037 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
3038 s
->username
[sizeof(s
->username
)-1] = '\0';
3041 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
3043 char userlog
[22 + sizeof(s
->username
)];
3044 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
3046 if (flags
& FLAG_INTERACTIVE
&&
3047 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
3048 strcat(userlog
, "\r\n");
3049 c_write_str(ssh
, userlog
);
3056 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
3057 /* We must not attempt PK auth. Pretend we've already tried it. */
3058 s
->tried_publickey
= s
->tried_agent
= 1;
3060 s
->tried_publickey
= s
->tried_agent
= 0;
3062 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
3063 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
3064 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
3065 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
3066 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
3067 s
->publickey_blob
= NULL
;
3069 s
->publickey_blob
= NULL
;
3071 while (pktin
->type
== SSH1_SMSG_FAILURE
) {
3072 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
3074 if (agent_exists() && !s
->tried_agent
) {
3076 * Attempt RSA authentication using Pageant.
3082 logevent("Pageant is running. Requesting keys.");
3084 /* Request the keys held by the agent. */
3085 PUT_32BIT(s
->request
, 1);
3086 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
3087 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
3088 ssh_agent_callback
, ssh
)) {
3092 bombout(("Unexpected data from server while waiting"
3093 " for agent response"));
3096 } while (pktin
|| inlen
> 0);
3097 r
= ssh
->agent_response
;
3098 s
->responselen
= ssh
->agent_response_len
;
3100 s
->response
= (unsigned char *) r
;
3101 if (s
->response
&& s
->responselen
>= 5 &&
3102 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
3103 s
->p
= s
->response
+ 5;
3104 s
->nkeys
= GET_32BIT(s
->p
);
3106 logeventf(ssh
, "Pageant has %d SSH-1 keys", s
->nkeys
);
3107 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
3108 logeventf(ssh
, "Trying Pageant key #%d", s
->keyi
);
3109 if (s
->publickey_blob
&&
3110 !memcmp(s
->p
, s
->publickey_blob
,
3111 s
->publickey_bloblen
)) {
3112 logevent("This key matches configured key file");
3113 s
->tried_publickey
= 1;
3118 do { /* do while (0) to make breaking easy */
3119 n
= ssh1_read_bignum
3120 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3125 n
= ssh1_read_bignum
3126 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3131 if (s
->responselen
- (s
->p
-s
->response
) < 4)
3133 s
->commentlen
= GET_32BIT(s
->p
);
3135 if (s
->responselen
- (s
->p
-s
->response
) <
3138 s
->commentp
= (char *)s
->p
;
3139 s
->p
+= s
->commentlen
;
3143 logevent("Pageant key list packet was truncated");
3147 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3148 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3150 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3151 logevent("Key refused");
3154 logevent("Received RSA challenge");
3155 if ((s
->challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3156 bombout(("Server's RSA challenge was badly formatted"));
3161 char *agentreq
, *q
, *ret
;
3164 len
= 1 + 4; /* message type, bit count */
3165 len
+= ssh1_bignum_length(s
->key
.exponent
);
3166 len
+= ssh1_bignum_length(s
->key
.modulus
);
3167 len
+= ssh1_bignum_length(s
->challenge
);
3168 len
+= 16; /* session id */
3169 len
+= 4; /* response format */
3170 agentreq
= snewn(4 + len
, char);
3171 PUT_32BIT(agentreq
, len
);
3173 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
3174 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
3176 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
3177 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
3178 q
+= ssh1_write_bignum(q
, s
->challenge
);
3179 memcpy(q
, s
->session_id
, 16);
3181 PUT_32BIT(q
, 1); /* response format */
3182 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
3183 ssh_agent_callback
, ssh
)) {
3188 bombout(("Unexpected data from server"
3189 " while waiting for agent"
3193 } while (pktin
|| inlen
> 0);
3194 vret
= ssh
->agent_response
;
3195 retlen
= ssh
->agent_response_len
;
3200 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
3201 logevent("Sending Pageant's response");
3202 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3203 PKT_DATA
, ret
+ 5, 16,
3207 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
3209 ("Pageant's response accepted");
3210 if (flags
& FLAG_VERBOSE
) {
3211 c_write_str(ssh
, "Authenticated using"
3213 c_write(ssh
, s
->commentp
,
3215 c_write_str(ssh
, "\" from agent\r\n");
3220 ("Pageant's response not accepted");
3223 ("Pageant failed to answer challenge");
3227 logevent("No reply received from Pageant");
3230 freebn(s
->key
.exponent
);
3231 freebn(s
->key
.modulus
);
3232 freebn(s
->challenge
);
3241 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
3242 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
3244 if (ssh
->cfg
.try_tis_auth
&&
3245 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3246 !s
->tis_auth_refused
) {
3247 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3248 logevent("Requested TIS authentication");
3249 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3251 if (pktin
->type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3252 logevent("TIS authentication declined");
3253 if (flags
& FLAG_INTERACTIVE
)
3254 c_write_str(ssh
, "TIS authentication refused.\r\n");
3255 s
->tis_auth_refused
= 1;
3261 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3263 bombout(("TIS challenge packet was badly formed"));
3266 c_write_str(ssh
, "Using TIS authentication.\r\n");
3267 logevent("Received TIS challenge");
3268 if (challengelen
> sizeof(s
->prompt
) - 1)
3269 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3270 memcpy(s
->prompt
, challenge
, challengelen
);
3271 /* Prompt heuristic comes from OpenSSH */
3272 strncpy(s
->prompt
+ challengelen
,
3273 memchr(s
->prompt
, '\n', challengelen
) ?
3274 "": "\r\nResponse: ",
3275 (sizeof s
->prompt
) - challengelen
);
3276 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
3279 if (ssh
->cfg
.try_tis_auth
&&
3280 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3281 !s
->ccard_auth_refused
) {
3282 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3283 logevent("Requested CryptoCard authentication");
3284 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3286 if (pktin
->type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3287 logevent("CryptoCard authentication declined");
3288 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3289 s
->ccard_auth_refused
= 1;
3295 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3297 bombout(("CryptoCard challenge packet was badly formed"));
3300 c_write_str(ssh
, "Using CryptoCard authentication.\r\n");
3301 logevent("Received CryptoCard challenge");
3302 if (challengelen
> sizeof(s
->prompt
) - 1)
3303 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3304 memcpy(s
->prompt
, challenge
, challengelen
);
3305 strncpy(s
->prompt
+ challengelen
,
3306 memchr(s
->prompt
, '\n', challengelen
) ?
3307 "" : "\r\nResponse: ",
3308 sizeof(s
->prompt
) - challengelen
);
3309 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
3312 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3313 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
3314 s
->username
, ssh
->savedhost
);
3316 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3317 char *comment
= NULL
;
3319 if (flags
& FLAG_VERBOSE
)
3320 c_write_str(ssh
, "Trying public key authentication.\r\n");
3321 logeventf(ssh
, "Trying public key \"%s\"",
3322 filename_to_str(&ssh
->cfg
.keyfile
));
3323 type
= key_type(&ssh
->cfg
.keyfile
);
3324 if (type
!= SSH_KEYTYPE_SSH1
) {
3325 char *msg
= dupprintf("Key is of wrong type (%s)",
3326 key_type_to_str(type
));
3328 c_write_str(ssh
, msg
);
3329 c_write_str(ssh
, "\r\n");
3331 s
->tried_publickey
= 1;
3334 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
3335 if (flags
& FLAG_VERBOSE
)
3336 c_write_str(ssh
, "No passphrase required.\r\n");
3339 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
3344 * Show password prompt, having first obtained it via a TIS
3345 * or CryptoCard exchange if we're doing TIS or CryptoCard
3349 if (!ssh_get_line(s
->prompt
, s
->password
,
3350 sizeof(s
->password
), TRUE
)) {
3352 * get_line failed to get a password (for example
3353 * because one was supplied on the command line
3354 * which has already failed to work). Terminate.
3356 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
3357 PKT_STR
, "No more passwords available to try",
3359 logevent("Unable to authenticate");
3360 connection_fatal(ssh
->frontend
, "Unable to authenticate");
3361 ssh
->close_expected
= TRUE
;
3362 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3366 /* Prompt may have come from server. We've munged it a bit, so
3367 * we know it to be zero-terminated at least once. */
3368 int ret
; /* need not be saved over crReturn */
3369 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3372 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3374 crWaitUntil(!pktin
);
3375 ret
= process_userpass_input(ssh
, in
, inlen
);
3379 c_write_str(ssh
, "\r\n");
3383 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3385 * Try public key authentication with the specified
3388 s
->tried_publickey
= 1;
3391 const char *error
= NULL
;
3392 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3395 c_write_str(ssh
, "Couldn't load private key from ");
3396 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3397 c_write_str(ssh
, " (");
3398 c_write_str(ssh
, error
);
3399 c_write_str(ssh
, ").\r\n");
3400 continue; /* go and try password */
3403 c_write_str(ssh
, "Wrong passphrase.\r\n");
3404 s
->tried_publickey
= 0;
3405 continue; /* try again */
3410 * Send a public key attempt.
3412 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3413 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3416 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3417 c_write_str(ssh
, "Server refused our public key.\r\n");
3418 continue; /* go and try password */
3420 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3421 bombout(("Bizarre response to offer of public key"));
3427 unsigned char buffer
[32];
3428 Bignum challenge
, response
;
3430 if ((challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3431 bombout(("Server's RSA challenge was badly formatted"));
3434 response
= rsadecrypt(challenge
, &s
->key
);
3435 freebn(s
->key
.private_exponent
);/* burn the evidence */
3437 for (i
= 0; i
< 32; i
++) {
3438 buffer
[i
] = bignum_byte(response
, 31 - i
);
3442 MD5Update(&md5c
, buffer
, 32);
3443 MD5Update(&md5c
, s
->session_id
, 16);
3444 MD5Final(buffer
, &md5c
);
3446 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3447 PKT_DATA
, buffer
, 16, PKT_END
);
3454 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3455 if (flags
& FLAG_VERBOSE
)
3456 c_write_str(ssh
, "Failed to authenticate with"
3457 " our public key.\r\n");
3458 continue; /* go and try password */
3459 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3460 bombout(("Bizarre response to RSA authentication response"));
3464 break; /* we're through! */
3466 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3468 * Defence against traffic analysis: we send a
3469 * whole bunch of packets containing strings of
3470 * different lengths. One of these strings is the
3471 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3472 * The others are all random data in
3473 * SSH1_MSG_IGNORE packets. This way a passive
3474 * listener can't tell which is the password, and
3475 * hence can't deduce the password length.
3477 * Anybody with a password length greater than 16
3478 * bytes is going to have enough entropy in their
3479 * password that a listener won't find it _that_
3480 * much help to know how long it is. So what we'll
3483 * - if password length < 16, we send 15 packets
3484 * containing string lengths 1 through 15
3486 * - otherwise, we let N be the nearest multiple
3487 * of 8 below the password length, and send 8
3488 * packets containing string lengths N through
3489 * N+7. This won't obscure the order of
3490 * magnitude of the password length, but it will
3491 * introduce a bit of extra uncertainty.
3493 * A few servers (the old 1.2.18 through 1.2.22)
3494 * can't deal with SSH1_MSG_IGNORE. For these
3495 * servers, we need an alternative defence. We make
3496 * use of the fact that the password is interpreted
3497 * as a C string: so we can append a NUL, then some
3500 * One server (a Cisco one) can deal with neither
3501 * SSH1_MSG_IGNORE _nor_ a padded password string.
3502 * For this server we are left with no defences
3503 * against password length sniffing.
3505 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3507 * The server can deal with SSH1_MSG_IGNORE, so
3508 * we can use the primary defence.
3510 int bottom
, top
, pwlen
, i
;
3513 pwlen
= strlen(s
->password
);
3515 bottom
= 0; /* zero length passwords are OK! :-) */
3518 bottom
= pwlen
& ~7;
3522 assert(pwlen
>= bottom
&& pwlen
<= top
);
3524 randomstr
= snewn(top
+ 1, char);
3526 for (i
= bottom
; i
<= top
; i
++) {
3528 defer_packet(ssh
, s
->pwpkt_type
,
3529 PKTT_PASSWORD
, PKT_STR
, s
->password
,
3530 PKTT_OTHER
, PKT_END
);
3532 for (j
= 0; j
< i
; j
++) {
3534 randomstr
[j
] = random_byte();
3535 } while (randomstr
[j
] == '\0');
3537 randomstr
[i
] = '\0';
3538 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3539 PKT_STR
, randomstr
, PKT_END
);
3542 logevent("Sending password with camouflage packets");
3543 ssh_pkt_defersend(ssh
);
3546 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3548 * The server can't deal with SSH1_MSG_IGNORE
3549 * but can deal with padded passwords, so we
3550 * can use the secondary defence.
3556 len
= strlen(s
->password
);
3557 if (len
< sizeof(string
)) {
3559 strcpy(string
, s
->password
);
3560 len
++; /* cover the zero byte */
3561 while (len
< sizeof(string
)) {
3562 string
[len
++] = (char) random_byte();
3567 logevent("Sending length-padded password");
3568 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3569 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3570 PKTT_OTHER
, PKT_END
);
3573 * The server has _both_
3574 * BUG_CHOKES_ON_SSH1_IGNORE and
3575 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3576 * therefore nothing we can do.
3579 len
= strlen(s
->password
);
3580 logevent("Sending unpadded password");
3581 send_packet(ssh
, s
->pwpkt_type
,
3582 PKTT_PASSWORD
, PKT_INT
, len
,
3583 PKT_DATA
, s
->password
, len
,
3584 PKTT_OTHER
, PKT_END
);
3587 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3588 PKT_STR
, s
->password
, PKTT_OTHER
, PKT_END
);
3591 logevent("Sent password");
3592 memset(s
->password
, 0, strlen(s
->password
));
3594 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3595 if (flags
& FLAG_VERBOSE
)
3596 c_write_str(ssh
, "Access denied\r\n");
3597 logevent("Authentication refused");
3598 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3599 bombout(("Strange packet received, type %d", pktin
->type
));
3604 logevent("Authentication successful");
3609 void sshfwd_close(struct ssh_channel
*c
)
3613 if (ssh
->state
== SSH_STATE_CLOSED
)
3616 if (c
&& !c
->closes
) {
3618 * If halfopen is true, we have sent
3619 * CHANNEL_OPEN for this channel, but it hasn't even been
3620 * acknowledged by the server. So we must set a close flag
3621 * on it now, and then when the server acks the channel
3622 * open, we can close it then.
3625 if (ssh
->version
== 1) {
3626 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3629 struct Packet
*pktout
;
3630 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3631 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
3632 ssh2_pkt_send(ssh
, pktout
);
3635 c
->closes
= 1; /* sent MSG_CLOSE */
3636 if (c
->type
== CHAN_X11
) {
3638 logevent("Forwarded X11 connection terminated");
3639 } else if (c
->type
== CHAN_SOCKDATA
||
3640 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3642 logevent("Forwarded port closed");
3647 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3651 if (ssh
->state
== SSH_STATE_CLOSED
)
3654 if (ssh
->version
== 1) {
3655 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3656 PKT_INT
, c
->remoteid
,
3658 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3659 PKTT_OTHER
, PKT_END
);
3661 * In SSH-1 we can return 0 here - implying that forwarded
3662 * connections are never individually throttled - because
3663 * the only circumstance that can cause throttling will be
3664 * the whole SSH connection backing up, in which case
3665 * _everything_ will be throttled as a whole.
3669 ssh2_add_channel_data(c
, buf
, len
);
3670 return ssh2_try_send(c
);
3674 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3678 if (ssh
->state
== SSH_STATE_CLOSED
)
3681 if (ssh
->version
== 1) {
3682 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3683 c
->v
.v1
.throttling
= 0;
3684 ssh1_throttle(ssh
, -1);
3687 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3691 static void ssh_queueing_handler(Ssh ssh
, struct Packet
*pktin
)
3693 struct queued_handler
*qh
= ssh
->qhead
;
3697 assert(pktin
->type
== qh
->msg1
|| pktin
->type
== qh
->msg2
);
3700 assert(ssh
->packet_dispatch
[qh
->msg1
] == ssh_queueing_handler
);
3701 ssh
->packet_dispatch
[qh
->msg1
] = NULL
;
3704 assert(ssh
->packet_dispatch
[qh
->msg2
] == ssh_queueing_handler
);
3705 ssh
->packet_dispatch
[qh
->msg2
] = NULL
;
3709 ssh
->qhead
= qh
->next
;
3711 if (ssh
->qhead
->msg1
> 0) {
3712 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg1
] == NULL
);
3713 ssh
->packet_dispatch
[ssh
->qhead
->msg1
] = ssh_queueing_handler
;
3715 if (ssh
->qhead
->msg2
> 0) {
3716 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg2
] == NULL
);
3717 ssh
->packet_dispatch
[ssh
->qhead
->msg2
] = ssh_queueing_handler
;
3720 ssh
->qhead
= ssh
->qtail
= NULL
;
3721 ssh
->packet_dispatch
[pktin
->type
] = NULL
;
3724 qh
->handler(ssh
, pktin
, qh
->ctx
);
3729 static void ssh_queue_handler(Ssh ssh
, int msg1
, int msg2
,
3730 chandler_fn_t handler
, void *ctx
)
3732 struct queued_handler
*qh
;
3734 qh
= snew(struct queued_handler
);
3737 qh
->handler
= handler
;
3741 if (ssh
->qtail
== NULL
) {
3745 assert(ssh
->packet_dispatch
[qh
->msg1
] == NULL
);
3746 ssh
->packet_dispatch
[qh
->msg1
] = ssh_queueing_handler
;
3749 assert(ssh
->packet_dispatch
[qh
->msg2
] == NULL
);
3750 ssh
->packet_dispatch
[qh
->msg2
] = ssh_queueing_handler
;
3753 ssh
->qtail
->next
= qh
;
3758 static void ssh_rportfwd_succfail(Ssh ssh
, struct Packet
*pktin
, void *ctx
)
3760 struct ssh_rportfwd
*rpf
, *pf
= (struct ssh_rportfwd
*)ctx
;
3762 if (pktin
->type
== (ssh
->version
== 1 ? SSH1_SMSG_SUCCESS
:
3763 SSH2_MSG_REQUEST_SUCCESS
)) {
3764 logeventf(ssh
, "Remote port forwarding from %s enabled",
3767 logeventf(ssh
, "Remote port forwarding from %s refused",
3770 rpf
= del234(ssh
->rportfwds
, pf
);
3776 static void ssh_setup_portfwd(Ssh ssh
, const Config
*cfg
)
3778 const char *portfwd_strptr
= cfg
->portfwd
;
3779 struct ssh_portfwd
*epf
;
3782 if (!ssh
->portfwds
) {
3783 ssh
->portfwds
= newtree234(ssh_portcmp
);
3786 * Go through the existing port forwardings and tag them
3787 * with status==DESTROY. Any that we want to keep will be
3788 * re-enabled (status==KEEP) as we go through the
3789 * configuration and find out which bits are the same as
3792 struct ssh_portfwd
*epf
;
3794 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3795 epf
->status
= DESTROY
;
3798 while (*portfwd_strptr
) {
3799 char address_family
, type
;
3800 int sport
,dport
,sserv
,dserv
;
3801 char sports
[256], dports
[256], saddr
[256], host
[256];
3804 address_family
= 'A';
3806 if (*portfwd_strptr
== 'A' ||
3807 *portfwd_strptr
== '4' ||
3808 *portfwd_strptr
== '6')
3809 address_family
= *portfwd_strptr
++;
3810 if (*portfwd_strptr
== 'L' ||
3811 *portfwd_strptr
== 'R' ||
3812 *portfwd_strptr
== 'D')
3813 type
= *portfwd_strptr
++;
3818 while (*portfwd_strptr
&& *portfwd_strptr
!= '\t') {
3819 if (*portfwd_strptr
== ':') {
3821 * We've seen a colon in the middle of the
3822 * source port number. This means that
3823 * everything we've seen until now is the
3824 * source _address_, so we'll move it into
3825 * saddr and start sports from the beginning
3830 if (ssh
->version
== 1 && type
== 'R') {
3831 logeventf(ssh
, "SSH-1 cannot handle remote source address "
3832 "spec \"%s\"; ignoring", sports
);
3834 strcpy(saddr
, sports
);
3837 if (n
< lenof(sports
)-1) sports
[n
++] = *portfwd_strptr
++;
3841 if (*portfwd_strptr
== '\t')
3844 while (*portfwd_strptr
&& *portfwd_strptr
!= ':') {
3845 if (n
< lenof(host
)-1) host
[n
++] = *portfwd_strptr
++;
3848 if (*portfwd_strptr
== ':')
3851 while (*portfwd_strptr
) {
3852 if (n
< lenof(dports
)-1) dports
[n
++] = *portfwd_strptr
++;
3856 dport
= atoi(dports
);
3860 dport
= net_service_lookup(dports
);
3862 logeventf(ssh
, "Service lookup failed for destination"
3863 " port \"%s\"", dports
);
3867 while (*portfwd_strptr
) portfwd_strptr
++;
3871 portfwd_strptr
++; /* eat the NUL and move to next one */
3873 sport
= atoi(sports
);
3877 sport
= net_service_lookup(sports
);
3879 logeventf(ssh
, "Service lookup failed for source"
3880 " port \"%s\"", sports
);
3883 if (sport
&& dport
) {
3884 /* Set up a description of the source port. */
3885 struct ssh_portfwd
*pfrec
, *epfrec
;
3887 pfrec
= snew(struct ssh_portfwd
);
3889 pfrec
->saddr
= *saddr ?
dupstr(saddr
) : NULL
;
3890 pfrec
->sserv
= sserv ?
dupstr(sports
) : NULL
;
3891 pfrec
->sport
= sport
;
3892 pfrec
->daddr
= *host ?
dupstr(host
) : NULL
;
3893 pfrec
->dserv
= dserv ?
dupstr(dports
) : NULL
;
3894 pfrec
->dport
= dport
;
3895 pfrec
->local
= NULL
;
3896 pfrec
->remote
= NULL
;
3897 pfrec
->addressfamily
= (address_family
== '4' ? ADDRTYPE_IPV4
:
3898 address_family
== '6' ? ADDRTYPE_IPV6
:
3901 epfrec
= add234(ssh
->portfwds
, pfrec
);
3902 if (epfrec
!= pfrec
) {
3904 * We already have a port forwarding with precisely
3905 * these parameters. Hence, no need to do anything;
3906 * simply tag the existing one as KEEP.
3908 epfrec
->status
= KEEP
;
3909 free_portfwd(pfrec
);
3911 pfrec
->status
= CREATE
;
3917 * Now go through and destroy any port forwardings which were
3920 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3921 if (epf
->status
== DESTROY
) {
3924 message
= dupprintf("%s port forwarding from %s%s%d",
3925 epf
->type
== 'L' ?
"local" :
3926 epf
->type
== 'R' ?
"remote" : "dynamic",
3927 epf
->saddr ? epf
->saddr
: "",
3928 epf
->saddr ?
":" : "",
3931 if (epf
->type
!= 'D') {
3932 char *msg2
= dupprintf("%s to %s:%d", message
,
3933 epf
->daddr
, epf
->dport
);
3938 logeventf(ssh
, "Cancelling %s", message
);
3942 struct ssh_rportfwd
*rpf
= epf
->remote
;
3943 struct Packet
*pktout
;
3946 * Cancel the port forwarding at the server
3949 if (ssh
->version
== 1) {
3951 * We cannot cancel listening ports on the
3952 * server side in SSH-1! There's no message
3953 * to support it. Instead, we simply remove
3954 * the rportfwd record from the local end
3955 * so that any connections the server tries
3956 * to make on it are rejected.
3959 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
3960 ssh2_pkt_addstring(pktout
, "cancel-tcpip-forward");
3961 ssh2_pkt_addbool(pktout
, 0);/* _don't_ want reply */
3963 ssh2_pkt_addstring(pktout
, epf
->saddr
);
3964 } else if (ssh
->cfg
.rport_acceptall
) {
3965 /* XXX: ssh->cfg.rport_acceptall may not represent
3966 * what was used to open the original connection,
3967 * since it's reconfigurable. */
3968 ssh2_pkt_addstring(pktout
, "0.0.0.0");
3970 ssh2_pkt_addstring(pktout
, "127.0.0.1");
3972 ssh2_pkt_adduint32(pktout
, epf
->sport
);
3973 ssh2_pkt_send(ssh
, pktout
);
3976 del234(ssh
->rportfwds
, rpf
);
3978 } else if (epf
->local
) {
3979 pfd_terminate(epf
->local
);
3982 delpos234(ssh
->portfwds
, i
);
3984 i
--; /* so we don't skip one in the list */
3988 * And finally, set up any new port forwardings (status==CREATE).
3990 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3991 if (epf
->status
== CREATE
) {
3992 char *sportdesc
, *dportdesc
;
3993 sportdesc
= dupprintf("%s%s%s%s%d%s",
3994 epf
->saddr ? epf
->saddr
: "",
3995 epf
->saddr ?
":" : "",
3996 epf
->sserv ? epf
->sserv
: "",
3997 epf
->sserv ?
"(" : "",
3999 epf
->sserv ?
")" : "");
4000 if (epf
->type
== 'D') {
4003 dportdesc
= dupprintf("%s:%s%s%d%s",
4005 epf
->dserv ? epf
->dserv
: "",
4006 epf
->dserv ?
"(" : "",
4008 epf
->dserv ?
")" : "");
4011 if (epf
->type
== 'L') {
4012 const char *err
= pfd_addforward(epf
->daddr
, epf
->dport
,
4013 epf
->saddr
, epf
->sport
,
4016 epf
->addressfamily
);
4018 logeventf(ssh
, "Local %sport %s forwarding to %s%s%s",
4019 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
4020 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
4021 sportdesc
, dportdesc
,
4022 err ?
" failed: " : "", err ? err
: "");
4023 } else if (epf
->type
== 'D') {
4024 const char *err
= pfd_addforward(NULL
, -1,
4025 epf
->saddr
, epf
->sport
,
4028 epf
->addressfamily
);
4030 logeventf(ssh
, "Local %sport %s SOCKS dynamic forwarding%s%s",
4031 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
4032 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
4034 err ?
" failed: " : "", err ? err
: "");
4036 struct ssh_rportfwd
*pf
;
4039 * Ensure the remote port forwardings tree exists.
4041 if (!ssh
->rportfwds
) {
4042 if (ssh
->version
== 1)
4043 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
4045 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
4048 pf
= snew(struct ssh_rportfwd
);
4049 strncpy(pf
->dhost
, epf
->daddr
, lenof(pf
->dhost
)-1);
4050 pf
->dhost
[lenof(pf
->dhost
)-1] = '\0';
4051 pf
->dport
= epf
->dport
;
4052 pf
->sport
= epf
->sport
;
4053 if (add234(ssh
->rportfwds
, pf
) != pf
) {
4054 logeventf(ssh
, "Duplicate remote port forwarding to %s:%d",
4055 epf
->daddr
, epf
->dport
);
4058 logeventf(ssh
, "Requesting remote port %s"
4059 " forward to %s", sportdesc
, dportdesc
);
4061 pf
->sportdesc
= sportdesc
;
4066 if (ssh
->version
== 1) {
4067 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
4068 PKT_INT
, epf
->sport
,
4069 PKT_STR
, epf
->daddr
,
4070 PKT_INT
, epf
->dport
,
4072 ssh_queue_handler(ssh
, SSH1_SMSG_SUCCESS
,
4074 ssh_rportfwd_succfail
, pf
);
4076 struct Packet
*pktout
;
4077 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
4078 ssh2_pkt_addstring(pktout
, "tcpip-forward");
4079 ssh2_pkt_addbool(pktout
, 1);/* want reply */
4081 ssh2_pkt_addstring(pktout
, epf
->saddr
);
4082 } else if (cfg
->rport_acceptall
) {
4083 ssh2_pkt_addstring(pktout
, "0.0.0.0");
4085 ssh2_pkt_addstring(pktout
, "127.0.0.1");
4087 ssh2_pkt_adduint32(pktout
, epf
->sport
);
4088 ssh2_pkt_send(ssh
, pktout
);
4090 ssh_queue_handler(ssh
, SSH2_MSG_REQUEST_SUCCESS
,
4091 SSH2_MSG_REQUEST_FAILURE
,
4092 ssh_rportfwd_succfail
, pf
);
4101 static void ssh1_smsg_stdout_stderr_data(Ssh ssh
, struct Packet
*pktin
)
4104 int stringlen
, bufsize
;
4106 ssh_pkt_getstring(pktin
, &string
, &stringlen
);
4107 if (string
== NULL
) {
4108 bombout(("Incoming terminal data packet was badly formed"));
4112 bufsize
= from_backend(ssh
->frontend
, pktin
->type
== SSH1_SMSG_STDERR_DATA
,
4114 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4115 ssh
->v1_stdout_throttling
= 1;
4116 ssh1_throttle(ssh
, +1);
4120 static void ssh1_smsg_x11_open(Ssh ssh
, struct Packet
*pktin
)
4122 /* Remote side is trying to open a channel to talk to our
4123 * X-Server. Give them back a local channel number. */
4124 struct ssh_channel
*c
;
4125 int remoteid
= ssh_pkt_getuint32(pktin
);
4127 logevent("Received X11 connect request");
4128 /* Refuse if X11 forwarding is disabled. */
4129 if (!ssh
->X11_fwd_enabled
) {
4130 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4131 PKT_INT
, remoteid
, PKT_END
);
4132 logevent("Rejected X11 connect request");
4134 c
= snew(struct ssh_channel
);
4137 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
4138 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
4139 logevent("Opening X11 forward connection failed");
4141 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4142 PKT_INT
, remoteid
, PKT_END
);
4145 ("Opening X11 forward connection succeeded");
4146 c
->remoteid
= remoteid
;
4147 c
->halfopen
= FALSE
;
4148 c
->localid
= alloc_channel_id(ssh
);
4150 c
->v
.v1
.throttling
= 0;
4151 c
->type
= CHAN_X11
; /* identify channel type */
4152 add234(ssh
->channels
, c
);
4153 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4154 PKT_INT
, c
->remoteid
, PKT_INT
,
4155 c
->localid
, PKT_END
);
4156 logevent("Opened X11 forward channel");
4161 static void ssh1_smsg_agent_open(Ssh ssh
, struct Packet
*pktin
)
4163 /* Remote side is trying to open a channel to talk to our
4164 * agent. Give them back a local channel number. */
4165 struct ssh_channel
*c
;
4166 int remoteid
= ssh_pkt_getuint32(pktin
);
4168 /* Refuse if agent forwarding is disabled. */
4169 if (!ssh
->agentfwd_enabled
) {
4170 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4171 PKT_INT
, remoteid
, PKT_END
);
4173 c
= snew(struct ssh_channel
);
4175 c
->remoteid
= remoteid
;
4176 c
->halfopen
= FALSE
;
4177 c
->localid
= alloc_channel_id(ssh
);
4179 c
->v
.v1
.throttling
= 0;
4180 c
->type
= CHAN_AGENT
; /* identify channel type */
4181 c
->u
.a
.lensofar
= 0;
4182 add234(ssh
->channels
, c
);
4183 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4184 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
4189 static void ssh1_msg_port_open(Ssh ssh
, struct Packet
*pktin
)
4191 /* Remote side is trying to open a channel to talk to a
4192 * forwarded port. Give them back a local channel number. */
4193 struct ssh_channel
*c
;
4194 struct ssh_rportfwd pf
, *pfp
;
4199 c
= snew(struct ssh_channel
);
4202 remoteid
= ssh_pkt_getuint32(pktin
);
4203 ssh_pkt_getstring(pktin
, &host
, &hostsize
);
4204 port
= ssh_pkt_getuint32(pktin
);
4206 if (hostsize
>= lenof(pf
.dhost
))
4207 hostsize
= lenof(pf
.dhost
)-1;
4208 memcpy(pf
.dhost
, host
, hostsize
);
4209 pf
.dhost
[hostsize
] = '\0';
4211 pfp
= find234(ssh
->rportfwds
, &pf
, NULL
);
4214 logeventf(ssh
, "Rejected remote port open request for %s:%d",
4216 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4217 PKT_INT
, remoteid
, PKT_END
);
4219 logeventf(ssh
, "Received remote port open request for %s:%d",
4221 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
4222 c
, &ssh
->cfg
, pfp
->pfrec
->addressfamily
);
4224 logeventf(ssh
, "Port open failed: %s", e
);
4226 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4227 PKT_INT
, remoteid
, PKT_END
);
4229 c
->remoteid
= remoteid
;
4230 c
->halfopen
= FALSE
;
4231 c
->localid
= alloc_channel_id(ssh
);
4233 c
->v
.v1
.throttling
= 0;
4234 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
4235 add234(ssh
->channels
, c
);
4236 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4237 PKT_INT
, c
->remoteid
, PKT_INT
,
4238 c
->localid
, PKT_END
);
4239 logevent("Forwarded port opened successfully");
4244 static void ssh1_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
4246 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4247 unsigned int localid
= ssh_pkt_getuint32(pktin
);
4248 struct ssh_channel
*c
;
4250 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4251 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4252 c
->remoteid
= localid
;
4253 c
->halfopen
= FALSE
;
4254 c
->type
= CHAN_SOCKDATA
;
4255 c
->v
.v1
.throttling
= 0;
4256 pfd_confirm(c
->u
.pfd
.s
);
4259 if (c
&& c
->closes
) {
4261 * We have a pending close on this channel,
4262 * which we decided on before the server acked
4263 * the channel open. So now we know the
4264 * remoteid, we can close it again.
4266 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
4267 PKT_INT
, c
->remoteid
, PKT_END
);
4271 static void ssh1_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
4273 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4274 struct ssh_channel
*c
;
4276 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4277 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4278 logevent("Forwarded connection refused by server");
4279 pfd_close(c
->u
.pfd
.s
);
4280 del234(ssh
->channels
, c
);
4285 static void ssh1_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
4287 /* Remote side closes a channel. */
4288 unsigned i
= ssh_pkt_getuint32(pktin
);
4289 struct ssh_channel
*c
;
4290 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4291 if (c
&& !c
->halfopen
) {
4294 (pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
4296 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
4297 logevent("Forwarded X11 connection terminated");
4298 assert(c
->u
.x11
.s
!= NULL
);
4299 x11_close(c
->u
.x11
.s
);
4302 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
4303 logevent("Forwarded port closed");
4304 assert(c
->u
.pfd
.s
!= NULL
);
4305 pfd_close(c
->u
.pfd
.s
);
4309 c
->closes
|= (closetype
<< 2); /* seen this message */
4310 if (!(c
->closes
& closetype
)) {
4311 send_packet(ssh
, pktin
->type
, PKT_INT
, c
->remoteid
,
4313 c
->closes
|= closetype
; /* sent it too */
4316 if (c
->closes
== 15) {
4317 del234(ssh
->channels
, c
);
4321 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4322 pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
4323 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
4328 static void ssh1_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
4330 /* Data sent down one of our channels. */
4331 int i
= ssh_pkt_getuint32(pktin
);
4334 struct ssh_channel
*c
;
4336 ssh_pkt_getstring(pktin
, &p
, &len
);
4338 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4343 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
4346 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
4349 /* Data for an agent message. Buffer it. */
4351 if (c
->u
.a
.lensofar
< 4) {
4352 unsigned int l
= min(4 - c
->u
.a
.lensofar
, len
);
4353 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
4357 c
->u
.a
.lensofar
+= l
;
4359 if (c
->u
.a
.lensofar
== 4) {
4361 4 + GET_32BIT(c
->u
.a
.msglen
);
4362 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
4364 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
4366 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
4368 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
4370 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
4374 c
->u
.a
.lensofar
+= l
;
4376 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
4379 if (agent_query(c
->u
.a
.message
,
4382 ssh_agentf_callback
, c
))
4383 ssh_agentf_callback(c
, reply
, replylen
);
4384 sfree(c
->u
.a
.message
);
4385 c
->u
.a
.lensofar
= 0;
4388 bufsize
= 0; /* agent channels never back up */
4391 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4392 c
->v
.v1
.throttling
= 1;
4393 ssh1_throttle(ssh
, +1);
4398 static void ssh1_smsg_exit_status(Ssh ssh
, struct Packet
*pktin
)
4400 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
4401 logeventf(ssh
, "Server sent command exit status %d", ssh
->exitcode
);
4402 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
4404 * In case `helpful' firewalls or proxies tack
4405 * extra human-readable text on the end of the
4406 * session which we might mistake for another
4407 * encrypted packet, we close the session once
4408 * we've sent EXIT_CONFIRMATION.
4410 ssh
->close_expected
= TRUE
;
4411 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4414 static void do_ssh1_connection(Ssh ssh
, unsigned char *in
, int inlen
,
4415 struct Packet
*pktin
)
4417 crBegin(ssh
->do_ssh1_connection_crstate
);
4419 ssh
->packet_dispatch
[SSH1_SMSG_STDOUT_DATA
] =
4420 ssh
->packet_dispatch
[SSH1_SMSG_STDERR_DATA
] =
4421 ssh1_smsg_stdout_stderr_data
;
4423 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
] =
4424 ssh1_msg_channel_open_confirmation
;
4425 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_FAILURE
] =
4426 ssh1_msg_channel_open_failure
;
4427 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE
] =
4428 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
] =
4429 ssh1_msg_channel_close
;
4430 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_DATA
] = ssh1_msg_channel_data
;
4431 ssh
->packet_dispatch
[SSH1_SMSG_EXIT_STATUS
] = ssh1_smsg_exit_status
;
4433 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
4434 logevent("Requesting agent forwarding");
4435 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
4439 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4440 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4441 bombout(("Protocol confusion"));
4443 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4444 logevent("Agent forwarding refused");
4446 logevent("Agent forwarding enabled");
4447 ssh
->agentfwd_enabled
= TRUE
;
4448 ssh
->packet_dispatch
[SSH1_SMSG_AGENT_OPEN
] = ssh1_smsg_agent_open
;
4452 if (ssh
->cfg
.x11_forward
) {
4453 char proto
[20], data
[64];
4454 logevent("Requesting X11 forwarding");
4455 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
4456 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
4457 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
4458 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
4459 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4460 PKT_STR
, proto
, PKT_STR
, data
,
4461 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
4464 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4465 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
4470 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4471 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4472 bombout(("Protocol confusion"));
4474 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4475 logevent("X11 forwarding refused");
4477 logevent("X11 forwarding enabled");
4478 ssh
->X11_fwd_enabled
= TRUE
;
4479 ssh
->packet_dispatch
[SSH1_SMSG_X11_OPEN
] = ssh1_smsg_x11_open
;
4483 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
4484 ssh
->packet_dispatch
[SSH1_MSG_PORT_OPEN
] = ssh1_msg_port_open
;
4486 if (!ssh
->cfg
.nopty
) {
4487 /* Unpick the terminal-speed string. */
4488 /* XXX perhaps we should allow no speeds to be sent. */
4489 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
4490 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
4491 /* Send the pty request. */
4492 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
4493 PKT_STR
, ssh
->cfg
.termtype
,
4494 PKT_INT
, ssh
->term_height
,
4495 PKT_INT
, ssh
->term_width
,
4496 PKT_INT
, 0, PKT_INT
, 0, /* width,height in pixels */
4497 PKT_CHAR
, 192, PKT_INT
, ssh
->ispeed
, /* TTY_OP_ISPEED */
4498 PKT_CHAR
, 193, PKT_INT
, ssh
->ospeed
, /* TTY_OP_OSPEED */
4499 PKT_CHAR
, 0, PKT_END
);
4500 ssh
->state
= SSH_STATE_INTERMED
;
4504 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4505 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4506 bombout(("Protocol confusion"));
4508 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4509 c_write_str(ssh
, "Server refused to allocate pty\r\n");
4510 ssh
->editing
= ssh
->echoing
= 1;
4512 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
4513 ssh
->ospeed
, ssh
->ispeed
);
4515 ssh
->editing
= ssh
->echoing
= 1;
4518 if (ssh
->cfg
.compression
) {
4519 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
4523 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4524 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4525 bombout(("Protocol confusion"));
4527 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4528 c_write_str(ssh
, "Server refused to compress\r\n");
4530 logevent("Started compression");
4531 ssh
->v1_compressing
= TRUE
;
4532 ssh
->cs_comp_ctx
= zlib_compress_init();
4533 logevent("Initialised zlib (RFC1950) compression");
4534 ssh
->sc_comp_ctx
= zlib_decompress_init();
4535 logevent("Initialised zlib (RFC1950) decompression");
4539 * Start the shell or command.
4541 * Special case: if the first-choice command is an SSH-2
4542 * subsystem (hence not usable here) and the second choice
4543 * exists, we fall straight back to that.
4546 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
4548 if (!cmd
) cmd
= ssh
->cfg
.remote_cmd
;
4550 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
4551 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
4552 ssh
->fallback_cmd
= TRUE
;
4555 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
4557 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
4558 logevent("Started session");
4561 ssh
->state
= SSH_STATE_SESSION
;
4562 if (ssh
->size_needed
)
4563 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
4564 if (ssh
->eof_needed
)
4565 ssh_special(ssh
, TS_EOF
);
4568 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
4570 ssh
->channels
= newtree234(ssh_channelcmp
);
4574 * By this point, most incoming packets are already being
4575 * handled by the dispatch table, and we need only pay
4576 * attention to the unusual ones.
4581 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
4582 /* may be from EXEC_SHELL on some servers */
4583 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4584 /* may be from EXEC_SHELL on some servers
4585 * if no pty is available or in other odd cases. Ignore */
4587 bombout(("Strange packet received: type %d", pktin
->type
));
4592 int len
= min(inlen
, 512);
4593 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4594 PKT_INT
, len
, PKT_DATA
, in
, len
,
4595 PKTT_OTHER
, PKT_END
);
4606 * Handle the top-level SSH-2 protocol.
4608 static void ssh1_msg_debug(Ssh ssh
, struct Packet
*pktin
)
4613 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4614 logeventf(ssh
, "Remote debug message: %.*s", msglen
, msg
);
4617 static void ssh1_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
4619 /* log reason code in disconnect message */
4623 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4624 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen
, msg
));
4627 static void ssh_msg_ignore(Ssh ssh
, struct Packet
*pktin
)
4629 /* Do nothing, because we're ignoring it! Duhh. */
4632 static void ssh1_protocol_setup(Ssh ssh
)
4637 * Most messages are handled by the coroutines.
4639 for (i
= 0; i
< 256; i
++)
4640 ssh
->packet_dispatch
[i
] = NULL
;
4643 * These special message types we install handlers for.
4645 ssh
->packet_dispatch
[SSH1_MSG_DISCONNECT
] = ssh1_msg_disconnect
;
4646 ssh
->packet_dispatch
[SSH1_MSG_IGNORE
] = ssh_msg_ignore
;
4647 ssh
->packet_dispatch
[SSH1_MSG_DEBUG
] = ssh1_msg_debug
;
4650 static void ssh1_protocol(Ssh ssh
, void *vin
, int inlen
,
4651 struct Packet
*pktin
)
4653 unsigned char *in
=(unsigned char*)vin
;
4654 if (ssh
->state
== SSH_STATE_CLOSED
)
4657 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
4658 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
4662 if (!ssh
->protocol_initial_phase_done
) {
4663 if (do_ssh1_login(ssh
, in
, inlen
, pktin
))
4664 ssh
->protocol_initial_phase_done
= TRUE
;
4669 do_ssh1_connection(ssh
, in
, inlen
, pktin
);
4673 * Utility routine for decoding comma-separated strings in KEXINIT.
4675 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
4678 if (!needle
|| !haystack
) /* protect against null pointers */
4680 needlen
= strlen(needle
);
4683 * Is it at the start of the string?
4685 if (haylen
>= needlen
&& /* haystack is long enough */
4686 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4687 (haylen
== needlen
|| haystack
[needlen
] == ',')
4688 /* either , or EOS follows */
4692 * If not, search for the next comma and resume after that.
4693 * If no comma found, terminate.
4695 while (haylen
> 0 && *haystack
!= ',')
4696 haylen
--, haystack
++;
4699 haylen
--, haystack
++; /* skip over comma itself */
4704 * Similar routine for checking whether we have the first string in a list.
4706 static int first_in_commasep_string(char *needle
, char *haystack
, int haylen
)
4709 if (!needle
|| !haystack
) /* protect against null pointers */
4711 needlen
= strlen(needle
);
4713 * Is it at the start of the string?
4715 if (haylen
>= needlen
&& /* haystack is long enough */
4716 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4717 (haylen
== needlen
|| haystack
[needlen
] == ',')
4718 /* either , or EOS follows */
4726 * SSH-2 key creation method.
4728 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
4729 unsigned char *sessid
, char chr
,
4730 unsigned char *keyspace
)
4733 /* First 20 bytes. */
4735 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4737 SHA_Bytes(&s
, H
, 20);
4738 SHA_Bytes(&s
, &chr
, 1);
4739 SHA_Bytes(&s
, sessid
, 20);
4740 SHA_Final(&s
, keyspace
);
4741 /* Next 20 bytes. */
4743 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4745 SHA_Bytes(&s
, H
, 20);
4746 SHA_Bytes(&s
, keyspace
, 20);
4747 SHA_Final(&s
, keyspace
+ 20);
4751 * Handle the SSH-2 transport layer.
4753 static int do_ssh2_transport(Ssh ssh
, void *vin
, int inlen
,
4754 struct Packet
*pktin
)
4756 unsigned char *in
= (unsigned char *)vin
;
4757 struct do_ssh2_transport_state
{
4758 int nbits
, pbits
, warn_kex
, warn_cscipher
, warn_sccipher
;
4759 Bignum p
, g
, e
, f
, K
;
4760 int kex_init_value
, kex_reply_value
;
4761 const struct ssh_mac
**maclist
;
4763 const struct ssh2_cipher
*cscipher_tobe
;
4764 const struct ssh2_cipher
*sccipher_tobe
;
4765 const struct ssh_mac
*csmac_tobe
;
4766 const struct ssh_mac
*scmac_tobe
;
4767 const struct ssh_compress
*cscomp_tobe
;
4768 const struct ssh_compress
*sccomp_tobe
;
4769 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4770 int hostkeylen
, siglen
;
4771 void *hkey
; /* actual host key */
4772 unsigned char exchange_hash
[20];
4773 int n_preferred_kex
;
4774 const struct ssh_kex
*preferred_kex
[KEX_MAX
];
4775 int n_preferred_ciphers
;
4776 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
4777 const struct ssh_compress
*preferred_comp
;
4778 int got_session_id
, activated_authconn
;
4779 struct Packet
*pktout
;
4784 crState(do_ssh2_transport_state
);
4786 crBegin(ssh
->do_ssh2_transport_crstate
);
4788 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
4789 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
4790 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
4792 s
->got_session_id
= s
->activated_authconn
= FALSE
;
4795 * Be prepared to work around the buggy MAC problem.
4797 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
4798 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
4800 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
4803 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_KEX_MASK
;
4805 int i
, j
, commalist_started
;
4808 * Set up the preferred key exchange. (NULL => warn below here)
4810 s
->n_preferred_kex
= 0;
4811 for (i
= 0; i
< KEX_MAX
; i
++) {
4812 switch (ssh
->cfg
.ssh_kexlist
[i
]) {
4814 s
->preferred_kex
[s
->n_preferred_kex
++] =
4815 &ssh_diffiehellman_gex
;
4818 s
->preferred_kex
[s
->n_preferred_kex
++] =
4819 &ssh_diffiehellman_group14
;
4822 s
->preferred_kex
[s
->n_preferred_kex
++] =
4823 &ssh_diffiehellman_group1
;
4826 /* Flag for later. Don't bother if it's the last in
4828 if (i
< KEX_MAX
- 1) {
4829 s
->preferred_kex
[s
->n_preferred_kex
++] = NULL
;
4836 * Set up the preferred ciphers. (NULL => warn below here)
4838 s
->n_preferred_ciphers
= 0;
4839 for (i
= 0; i
< CIPHER_MAX
; i
++) {
4840 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
4841 case CIPHER_BLOWFISH
:
4842 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
4845 if (ssh
->cfg
.ssh2_des_cbc
) {
4846 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
4850 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
4853 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
4855 case CIPHER_ARCFOUR
:
4856 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_arcfour
;
4859 /* Flag for later. Don't bother if it's the last in
4861 if (i
< CIPHER_MAX
- 1) {
4862 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
4869 * Set up preferred compression.
4871 if (ssh
->cfg
.compression
)
4872 s
->preferred_comp
= &ssh_zlib
;
4874 s
->preferred_comp
= &ssh_comp_none
;
4877 * Enable queueing of outgoing auth- or connection-layer
4878 * packets while we are in the middle of a key exchange.
4880 ssh
->queueing
= TRUE
;
4883 * Flag that KEX is in progress.
4885 ssh
->kex_in_progress
= TRUE
;
4888 * Construct and send our key exchange packet.
4890 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEXINIT
);
4891 for (i
= 0; i
< 16; i
++)
4892 ssh2_pkt_addbyte(s
->pktout
, (unsigned char) random_byte());
4893 /* List key exchange algorithms. */
4894 ssh2_pkt_addstring_start(s
->pktout
);
4895 commalist_started
= 0;
4896 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4897 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4898 if (!k
) continue; /* warning flag */
4899 if (commalist_started
)
4900 ssh2_pkt_addstring_str(s
->pktout
, ",");
4901 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_kex
[i
]->name
);
4902 commalist_started
= 1;
4904 /* List server host key algorithms. */
4905 ssh2_pkt_addstring_start(s
->pktout
);
4906 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4907 ssh2_pkt_addstring_str(s
->pktout
, hostkey_algs
[i
]->name
);
4908 if (i
< lenof(hostkey_algs
) - 1)
4909 ssh2_pkt_addstring_str(s
->pktout
, ",");
4911 /* List client->server encryption algorithms. */
4912 ssh2_pkt_addstring_start(s
->pktout
);
4913 commalist_started
= 0;
4914 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4915 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4916 if (!c
) continue; /* warning flag */
4917 for (j
= 0; j
< c
->nciphers
; j
++) {
4918 if (commalist_started
)
4919 ssh2_pkt_addstring_str(s
->pktout
, ",");
4920 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4921 commalist_started
= 1;
4924 /* List server->client encryption algorithms. */
4925 ssh2_pkt_addstring_start(s
->pktout
);
4926 commalist_started
= 0;
4927 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4928 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4929 if (!c
) continue; /* warning flag */
4930 for (j
= 0; j
< c
->nciphers
; j
++) {
4931 if (commalist_started
)
4932 ssh2_pkt_addstring_str(s
->pktout
, ",");
4933 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4934 commalist_started
= 1;
4937 /* List client->server MAC algorithms. */
4938 ssh2_pkt_addstring_start(s
->pktout
);
4939 for (i
= 0; i
< s
->nmacs
; i
++) {
4940 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4941 if (i
< s
->nmacs
- 1)
4942 ssh2_pkt_addstring_str(s
->pktout
, ",");
4944 /* List server->client MAC algorithms. */
4945 ssh2_pkt_addstring_start(s
->pktout
);
4946 for (i
= 0; i
< s
->nmacs
; i
++) {
4947 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4948 if (i
< s
->nmacs
- 1)
4949 ssh2_pkt_addstring_str(s
->pktout
, ",");
4951 /* List client->server compression algorithms. */
4952 ssh2_pkt_addstring_start(s
->pktout
);
4953 assert(lenof(compressions
) > 1);
4954 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4955 for (i
= 0; i
< lenof(compressions
); i
++) {
4956 const struct ssh_compress
*c
= compressions
[i
];
4957 if (c
!= s
->preferred_comp
) {
4958 ssh2_pkt_addstring_str(s
->pktout
, ",");
4959 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4962 /* List server->client compression algorithms. */
4963 ssh2_pkt_addstring_start(s
->pktout
);
4964 assert(lenof(compressions
) > 1);
4965 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4966 for (i
= 0; i
< lenof(compressions
); i
++) {
4967 const struct ssh_compress
*c
= compressions
[i
];
4968 if (c
!= s
->preferred_comp
) {
4969 ssh2_pkt_addstring_str(s
->pktout
, ",");
4970 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4973 /* List client->server languages. Empty list. */
4974 ssh2_pkt_addstring_start(s
->pktout
);
4975 /* List server->client languages. Empty list. */
4976 ssh2_pkt_addstring_start(s
->pktout
);
4977 /* First KEX packet does _not_ follow, because we're not that brave. */
4978 ssh2_pkt_addbool(s
->pktout
, FALSE
);
4980 ssh2_pkt_adduint32(s
->pktout
, 0);
4983 ssh
->exhash
= ssh
->exhashbase
;
4984 sha_string(&ssh
->exhash
, s
->pktout
->data
+ 5, s
->pktout
->length
- 5);
4986 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
4990 if (pktin
->length
> 5)
4991 sha_string(&ssh
->exhash
, pktin
->data
+ 5, pktin
->length
- 5);
4994 * Now examine the other side's KEXINIT to see what we're up
4998 char *str
, *preferred
;
5001 if (pktin
->type
!= SSH2_MSG_KEXINIT
) {
5002 bombout(("expected key exchange packet from server"));
5006 ssh
->hostkey
= NULL
;
5007 s
->cscipher_tobe
= NULL
;
5008 s
->sccipher_tobe
= NULL
;
5009 s
->csmac_tobe
= NULL
;
5010 s
->scmac_tobe
= NULL
;
5011 s
->cscomp_tobe
= NULL
;
5012 s
->sccomp_tobe
= NULL
;
5013 s
->warn_kex
= s
->warn_cscipher
= s
->warn_sccipher
= FALSE
;
5015 pktin
->savedpos
+= 16; /* skip garbage cookie */
5016 ssh_pkt_getstring(pktin
, &str
, &len
); /* key exchange algorithms */
5019 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
5020 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
5024 if (!preferred
) preferred
= k
->name
;
5025 if (in_commasep_string(k
->name
, str
, len
))
5032 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
5033 str ? str
: "(null)"));
5037 * Note that the server's guess is considered wrong if it doesn't match
5038 * the first algorithm in our list, even if it's still the algorithm
5041 s
->guessok
= first_in_commasep_string(preferred
, str
, len
);
5042 ssh_pkt_getstring(pktin
, &str
, &len
); /* host key algorithms */
5043 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
5044 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
5045 ssh
->hostkey
= hostkey_algs
[i
];
5049 s
->guessok
= s
->guessok
&&
5050 first_in_commasep_string(hostkey_algs
[0]->name
, str
, len
);
5051 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server cipher */
5052 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5053 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5055 s
->warn_cscipher
= TRUE
;
5057 for (j
= 0; j
< c
->nciphers
; j
++) {
5058 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
5059 s
->cscipher_tobe
= c
->list
[j
];
5064 if (s
->cscipher_tobe
)
5067 if (!s
->cscipher_tobe
) {
5068 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
5069 str ? str
: "(null)"));
5073 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client cipher */
5074 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5075 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5077 s
->warn_sccipher
= TRUE
;
5079 for (j
= 0; j
< c
->nciphers
; j
++) {
5080 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
5081 s
->sccipher_tobe
= c
->list
[j
];
5086 if (s
->sccipher_tobe
)
5089 if (!s
->sccipher_tobe
) {
5090 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
5091 str ? str
: "(null)"));
5095 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server mac */
5096 for (i
= 0; i
< s
->nmacs
; i
++) {
5097 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5098 s
->csmac_tobe
= s
->maclist
[i
];
5102 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client mac */
5103 for (i
= 0; i
< s
->nmacs
; i
++) {
5104 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5105 s
->scmac_tobe
= s
->maclist
[i
];
5109 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server compression */
5110 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5111 const struct ssh_compress
*c
=
5112 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5113 if (in_commasep_string(c
->name
, str
, len
)) {
5118 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client compression */
5119 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5120 const struct ssh_compress
*c
=
5121 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5122 if (in_commasep_string(c
->name
, str
, len
)) {
5127 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server language */
5128 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client language */
5129 s
->ignorepkt
= ssh2_pkt_getbool(pktin
) && !s
->guessok
;
5132 ssh_set_frozen(ssh
, 1);
5133 s
->dlgret
= askalg(ssh
->frontend
, "key-exchange algorithm",
5135 ssh_dialog_callback
, ssh
);
5136 if (s
->dlgret
< 0) {
5140 bombout(("Unexpected data from server while"
5141 " waiting for user response"));
5144 } while (pktin
|| inlen
> 0);
5145 s
->dlgret
= ssh
->user_response
;
5147 ssh_set_frozen(ssh
, 0);
5148 if (s
->dlgret
== 0) {
5149 ssh
->close_expected
= TRUE
;
5150 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5155 if (s
->warn_cscipher
) {
5156 ssh_set_frozen(ssh
, 1);
5157 s
->dlgret
= askalg(ssh
->frontend
,
5158 "client-to-server cipher",
5159 s
->cscipher_tobe
->name
,
5160 ssh_dialog_callback
, ssh
);
5161 if (s
->dlgret
< 0) {
5165 bombout(("Unexpected data from server while"
5166 " waiting for user response"));
5169 } while (pktin
|| inlen
> 0);
5170 s
->dlgret
= ssh
->user_response
;
5172 ssh_set_frozen(ssh
, 0);
5173 if (s
->dlgret
== 0) {
5174 ssh
->close_expected
= TRUE
;
5175 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5180 if (s
->warn_sccipher
) {
5181 ssh_set_frozen(ssh
, 1);
5182 s
->dlgret
= askalg(ssh
->frontend
,
5183 "server-to-client cipher",
5184 s
->sccipher_tobe
->name
,
5185 ssh_dialog_callback
, ssh
);
5186 if (s
->dlgret
< 0) {
5190 bombout(("Unexpected data from server while"
5191 " waiting for user response"));
5194 } while (pktin
|| inlen
> 0);
5195 s
->dlgret
= ssh
->user_response
;
5197 ssh_set_frozen(ssh
, 0);
5198 if (s
->dlgret
== 0) {
5199 ssh
->close_expected
= TRUE
;
5200 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5205 if (s
->ignorepkt
) /* first_kex_packet_follows */
5206 crWaitUntil(pktin
); /* Ignore packet */
5210 * Work out the number of bits of key we will need from the key
5211 * exchange. We start with the maximum key length of either
5217 csbits
= s
->cscipher_tobe
->keylen
;
5218 scbits
= s
->sccipher_tobe
->keylen
;
5219 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
5221 /* The keys only have 160-bit entropy, since they're based on
5222 * a SHA-1 hash. So cap the key size at 160 bits. */
5227 * If we're doing Diffie-Hellman group exchange, start by
5228 * requesting a group.
5230 if (!ssh
->kex
->pdata
) {
5231 logevent("Doing Diffie-Hellman group exchange");
5232 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
5234 * Work out how big a DH group we will need to allow that
5237 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
5238 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
5239 ssh2_pkt_adduint32(s
->pktout
, s
->pbits
);
5240 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5243 if (pktin
->type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
5244 bombout(("expected key exchange group packet from server"));
5247 s
->p
= ssh2_pkt_getmp(pktin
);
5248 s
->g
= ssh2_pkt_getmp(pktin
);
5249 if (!s
->p
|| !s
->g
) {
5250 bombout(("unable to read mp-ints from incoming group packet"));
5253 ssh
->kex_ctx
= dh_setup_gex(s
->p
, s
->g
);
5254 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
5255 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
5257 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP
;
5258 ssh
->kex_ctx
= dh_setup_group(ssh
->kex
);
5259 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
5260 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
5261 logeventf(ssh
, "Using Diffie-Hellman with standard group \"%s\"",
5262 ssh
->kex
->groupname
);
5265 logevent("Doing Diffie-Hellman key exchange");
5267 * Now generate and send e for Diffie-Hellman.
5269 set_busy_status(ssh
->frontend
, BUSY_CPU
); /* this can take a while */
5270 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
5271 s
->pktout
= ssh2_pkt_init(s
->kex_init_value
);
5272 ssh2_pkt_addmp(s
->pktout
, s
->e
);
5273 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5275 set_busy_status(ssh
->frontend
, BUSY_WAITING
); /* wait for server */
5277 if (pktin
->type
!= s
->kex_reply_value
) {
5278 bombout(("expected key exchange reply packet from server"));
5281 set_busy_status(ssh
->frontend
, BUSY_CPU
); /* cogitate */
5282 ssh_pkt_getstring(pktin
, &s
->hostkeydata
, &s
->hostkeylen
);
5283 s
->f
= ssh2_pkt_getmp(pktin
);
5285 bombout(("unable to parse key exchange reply packet"));
5288 ssh_pkt_getstring(pktin
, &s
->sigdata
, &s
->siglen
);
5290 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
5292 /* We assume everything from now on will be quick, and it might
5293 * involve user interaction. */
5294 set_busy_status(ssh
->frontend
, BUSY_NOT
);
5296 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
5297 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5298 sha_uint32(&ssh
->exhash
, s
->pbits
);
5299 sha_mpint(&ssh
->exhash
, s
->p
);
5300 sha_mpint(&ssh
->exhash
, s
->g
);
5302 sha_mpint(&ssh
->exhash
, s
->e
);
5303 sha_mpint(&ssh
->exhash
, s
->f
);
5304 sha_mpint(&ssh
->exhash
, s
->K
);
5305 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
5307 dh_cleanup(ssh
->kex_ctx
);
5308 ssh
->kex_ctx
= NULL
;
5311 debug(("Exchange hash is:\n"));
5312 dmemdump(s
->exchange_hash
, 20);
5315 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
5317 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
5318 (char *)s
->exchange_hash
, 20)) {
5319 bombout(("Server's host key did not match the signature supplied"));
5324 * Authenticate remote host: verify host key. (We've already
5325 * checked the signature of the exchange hash.)
5327 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
5328 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
5329 ssh_set_frozen(ssh
, 1);
5330 s
->dlgret
= verify_ssh_host_key(ssh
->frontend
,
5331 ssh
->savedhost
, ssh
->savedport
,
5332 ssh
->hostkey
->keytype
, s
->keystr
,
5334 ssh_dialog_callback
, ssh
);
5335 if (s
->dlgret
< 0) {
5339 bombout(("Unexpected data from server while waiting"
5340 " for user host key response"));
5343 } while (pktin
|| inlen
> 0);
5344 s
->dlgret
= ssh
->user_response
;
5346 ssh_set_frozen(ssh
, 0);
5347 if (s
->dlgret
== 0) {
5348 ssh
->close_expected
= TRUE
;
5349 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5352 if (!s
->got_session_id
) { /* don't bother logging this in rekeys */
5353 logevent("Host key fingerprint is:");
5354 logevent(s
->fingerprint
);
5356 sfree(s
->fingerprint
);
5358 ssh
->hostkey
->freekey(s
->hkey
);
5361 * The exchange hash from the very first key exchange is also
5362 * the session id, used in session key construction and
5365 if (!s
->got_session_id
) {
5366 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
5367 sizeof(s
->exchange_hash
));
5368 s
->got_session_id
= TRUE
;
5372 * Send SSH2_MSG_NEWKEYS.
5374 s
->pktout
= ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
5375 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5376 ssh
->outgoing_data_size
= 0; /* start counting from here */
5379 * We've sent client NEWKEYS, so create and initialise
5380 * client-to-server session keys.
5382 if (ssh
->cs_cipher_ctx
)
5383 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
5384 ssh
->cscipher
= s
->cscipher_tobe
;
5385 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
5387 if (ssh
->cs_mac_ctx
)
5388 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
5389 ssh
->csmac
= s
->csmac_tobe
;
5390 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
5392 if (ssh
->cs_comp_ctx
)
5393 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
5394 ssh
->cscomp
= s
->cscomp_tobe
;
5395 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
5398 * Set IVs on client-to-server keys. Here we use the exchange
5399 * hash from the _first_ key exchange.
5402 unsigned char keyspace
[40];
5403 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
5404 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
5405 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
5406 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
5407 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
5408 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
5411 logeventf(ssh
, "Initialised %.200s client->server encryption",
5412 ssh
->cscipher
->text_name
);
5413 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
5414 ssh
->csmac
->text_name
);
5415 if (ssh
->cscomp
->text_name
)
5416 logeventf(ssh
, "Initialised %s compression",
5417 ssh
->cscomp
->text_name
);
5420 * Now our end of the key exchange is complete, we can send all
5421 * our queued higher-layer packets.
5423 ssh
->queueing
= FALSE
;
5424 ssh2_pkt_queuesend(ssh
);
5427 * Expect SSH2_MSG_NEWKEYS from server.
5430 if (pktin
->type
!= SSH2_MSG_NEWKEYS
) {
5431 bombout(("expected new-keys packet from server"));
5434 ssh
->incoming_data_size
= 0; /* start counting from here */
5437 * We've seen server NEWKEYS, so create and initialise
5438 * server-to-client session keys.
5440 if (ssh
->sc_cipher_ctx
)
5441 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
5442 ssh
->sccipher
= s
->sccipher_tobe
;
5443 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
5445 if (ssh
->sc_mac_ctx
)
5446 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
5447 ssh
->scmac
= s
->scmac_tobe
;
5448 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
5450 if (ssh
->sc_comp_ctx
)
5451 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
5452 ssh
->sccomp
= s
->sccomp_tobe
;
5453 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
5456 * Set IVs on server-to-client keys. Here we use the exchange
5457 * hash from the _first_ key exchange.
5460 unsigned char keyspace
[40];
5461 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
5462 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
5463 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
5464 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
5465 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
5466 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
5468 logeventf(ssh
, "Initialised %.200s server->client encryption",
5469 ssh
->sccipher
->text_name
);
5470 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
5471 ssh
->scmac
->text_name
);
5472 if (ssh
->sccomp
->text_name
)
5473 logeventf(ssh
, "Initialised %s decompression",
5474 ssh
->sccomp
->text_name
);
5477 * Free key exchange data.
5481 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5487 * Key exchange is over. Loop straight back round if we have a
5488 * deferred rekey reason.
5490 if (ssh
->deferred_rekey_reason
) {
5491 logevent(ssh
->deferred_rekey_reason
);
5493 ssh
->deferred_rekey_reason
= NULL
;
5494 goto begin_key_exchange
;
5498 * Otherwise, schedule a timer for our next rekey.
5500 ssh
->kex_in_progress
= FALSE
;
5501 ssh
->last_rekey
= GETTICKCOUNT();
5502 if (ssh
->cfg
.ssh_rekey_time
!= 0)
5503 ssh
->next_rekey
= schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5507 * If this is the first key exchange phase, we must pass the
5508 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5509 * wants to see it but because it will need time to initialise
5510 * itself before it sees an actual packet. In subsequent key
5511 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5512 * it would only confuse the layer above.
5514 if (s
->activated_authconn
) {
5517 s
->activated_authconn
= TRUE
;
5520 * Now we're encrypting. Begin returning 1 to the protocol main
5521 * function so that other things can run on top of the
5522 * transport. If we ever see a KEXINIT, we must go back to the
5525 * We _also_ go back to the start if we see pktin==NULL and
5526 * inlen==-1, because this is a special signal meaning
5527 * `initiate client-driven rekey', and `in' contains a message
5528 * giving the reason for the rekey.
5530 while (!((pktin
&& pktin
->type
== SSH2_MSG_KEXINIT
) ||
5531 (!pktin
&& inlen
== -1))) {
5536 logevent("Server initiated key re-exchange");
5539 * Special case: if the server bug is set that doesn't
5540 * allow rekeying, we give a different log message and
5541 * continue waiting. (If such a server _initiates_ a rekey,
5542 * we process it anyway!)
5544 if ((ssh
->remote_bugs
& BUG_SSH2_REKEY
)) {
5545 logeventf(ssh
, "Server bug prevents key re-exchange (%s)",
5547 /* Reset the counters, so that at least this message doesn't
5548 * hit the event log _too_ often. */
5549 ssh
->outgoing_data_size
= 0;
5550 ssh
->incoming_data_size
= 0;
5551 if (ssh
->cfg
.ssh_rekey_time
!= 0) {
5553 schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5556 goto wait_for_rekey
; /* this is utterly horrid */
5558 logeventf(ssh
, "Initiating key re-exchange (%s)", (char *)in
);
5561 goto begin_key_exchange
;
5567 * Add data to an SSH-2 channel output buffer.
5569 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
5572 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
5576 * Attempt to send data on an SSH-2 channel.
5578 static int ssh2_try_send(struct ssh_channel
*c
)
5581 struct Packet
*pktout
;
5583 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
5586 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
5587 if ((unsigned)len
> c
->v
.v2
.remwindow
)
5588 len
= c
->v
.v2
.remwindow
;
5589 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
5590 len
= c
->v
.v2
.remmaxpkt
;
5591 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
5592 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5593 dont_log_data(ssh
, pktout
, PKTLOG_OMIT
);
5594 ssh2_pkt_addstring_start(pktout
);
5595 ssh2_pkt_addstring_data(pktout
, data
, len
);
5596 end_log_omission(ssh
, pktout
);
5597 ssh2_pkt_send(ssh
, pktout
);
5598 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
5599 c
->v
.v2
.remwindow
-= len
;
5603 * After having sent as much data as we can, return the amount
5606 return bufchain_size(&c
->v
.v2
.outbuffer
);
5609 static void ssh2_try_send_and_unthrottle(struct ssh_channel
*c
)
5613 return; /* don't send on closing channels */
5614 bufsize
= ssh2_try_send(c
);
5617 case CHAN_MAINSESSION
:
5618 /* stdin need not receive an unthrottle
5619 * notification since it will be polled */
5622 x11_unthrottle(c
->u
.x11
.s
);
5625 /* agent sockets are request/response and need no
5626 * buffer management */
5629 pfd_unthrottle(c
->u
.pfd
.s
);
5636 * Potentially enlarge the window on an SSH-2 channel.
5638 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
5643 * Never send WINDOW_ADJUST for a channel that the remote side
5644 * already thinks it's closed; there's no point, since it won't
5645 * be sending any more data anyway.
5651 * Only send a WINDOW_ADJUST if there's significantly more window
5652 * available than the other end thinks there is. This saves us
5653 * sending a WINDOW_ADJUST for every character in a shell session.
5655 * "Significant" is arbitrarily defined as half the window size.
5657 if (newwin
> c
->v
.v2
.locwindow
* 2) {
5658 struct Packet
*pktout
;
5660 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5661 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5662 ssh2_pkt_adduint32(pktout
, newwin
- c
->v
.v2
.locwindow
);
5663 ssh2_pkt_send(ssh
, pktout
);
5664 c
->v
.v2
.locwindow
= newwin
;
5668 static void ssh2_msg_channel_window_adjust(Ssh ssh
, struct Packet
*pktin
)
5670 unsigned i
= ssh_pkt_getuint32(pktin
);
5671 struct ssh_channel
*c
;
5672 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5673 if (c
&& !c
->closes
) {
5674 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
5675 ssh2_try_send_and_unthrottle(c
);
5679 static void ssh2_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
5683 unsigned i
= ssh_pkt_getuint32(pktin
);
5684 struct ssh_channel
*c
;
5685 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5687 return; /* nonexistent channel */
5688 if (pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5689 ssh_pkt_getuint32(pktin
) != SSH2_EXTENDED_DATA_STDERR
)
5690 return; /* extended but not stderr */
5691 ssh_pkt_getstring(pktin
, &data
, &length
);
5694 c
->v
.v2
.locwindow
-= length
;
5696 case CHAN_MAINSESSION
:
5698 from_backend(ssh
->frontend
, pktin
->type
==
5699 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5703 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5706 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5709 while (length
> 0) {
5710 if (c
->u
.a
.lensofar
< 4) {
5711 unsigned int l
= min(4 - c
->u
.a
.lensofar
, length
);
5712 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5716 c
->u
.a
.lensofar
+= l
;
5718 if (c
->u
.a
.lensofar
== 4) {
5720 4 + GET_32BIT(c
->u
.a
.msglen
);
5721 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
5723 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5725 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5727 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5729 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5733 c
->u
.a
.lensofar
+= l
;
5735 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5738 if (agent_query(c
->u
.a
.message
,
5741 ssh_agentf_callback
, c
))
5742 ssh_agentf_callback(c
, reply
, replylen
);
5743 sfree(c
->u
.a
.message
);
5744 c
->u
.a
.lensofar
= 0;
5751 * If we are not buffering too much data,
5752 * enlarge the window again at the remote side.
5754 if (bufsize
< OUR_V2_WINSIZE
)
5755 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5759 static void ssh2_msg_channel_eof(Ssh ssh
, struct Packet
*pktin
)
5761 unsigned i
= ssh_pkt_getuint32(pktin
);
5762 struct ssh_channel
*c
;
5764 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5766 return; /* nonexistent channel */
5768 if (c
->type
== CHAN_X11
) {
5770 * Remote EOF on an X11 channel means we should
5771 * wrap up and close the channel ourselves.
5773 x11_close(c
->u
.x11
.s
);
5775 } else if (c
->type
== CHAN_AGENT
) {
5777 } else if (c
->type
== CHAN_SOCKDATA
) {
5778 pfd_close(c
->u
.pfd
.s
);
5783 static void ssh2_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
5785 unsigned i
= ssh_pkt_getuint32(pktin
);
5786 struct ssh_channel
*c
;
5787 struct Packet
*pktout
;
5789 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5790 if (!c
|| c
->halfopen
) {
5791 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5792 c ?
"half-open" : "nonexistent", i
));
5795 /* Do pre-close processing on the channel. */
5797 case CHAN_MAINSESSION
:
5798 ssh
->mainchan
= NULL
;
5799 update_specials_menu(ssh
->frontend
);
5802 if (c
->u
.x11
.s
!= NULL
)
5803 x11_close(c
->u
.x11
.s
);
5810 if (c
->u
.pfd
.s
!= NULL
)
5811 pfd_close(c
->u
.pfd
.s
);
5815 if (c
->closes
== 0) {
5816 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5817 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5818 ssh2_pkt_send(ssh
, pktout
);
5820 del234(ssh
->channels
, c
);
5821 bufchain_clear(&c
->v
.v2
.outbuffer
);
5825 * See if that was the last channel left open.
5826 * (This is only our termination condition if we're
5827 * not running in -N mode.)
5829 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
5830 logevent("All channels closed. Disconnecting");
5833 * We used to send SSH_MSG_DISCONNECT here,
5834 * because I'd believed that _every_ conforming
5835 * SSH-2 connection had to end with a disconnect
5836 * being sent by at least one side; apparently
5837 * I was wrong and it's perfectly OK to
5838 * unceremoniously slam the connection shut
5839 * when you're done, and indeed OpenSSH feels
5840 * this is more polite than sending a
5841 * DISCONNECT. So now we don't.
5843 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5844 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5845 ssh2_pkt_addstring(s
->pktout
, "All open channels closed");
5846 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
5847 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5849 ssh
->close_expected
= TRUE
;
5850 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5854 static void ssh2_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
5856 unsigned i
= ssh_pkt_getuint32(pktin
);
5857 struct ssh_channel
*c
;
5858 struct Packet
*pktout
;
5860 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5862 return; /* nonexistent channel */
5863 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5864 return; /* dunno why they're confirming this */
5865 c
->remoteid
= ssh_pkt_getuint32(pktin
);
5866 c
->halfopen
= FALSE
;
5867 c
->type
= CHAN_SOCKDATA
;
5868 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
5869 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
5871 pfd_confirm(c
->u
.pfd
.s
);
5874 * We have a pending close on this channel,
5875 * which we decided on before the server acked
5876 * the channel open. So now we know the
5877 * remoteid, we can close it again.
5879 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5880 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5881 ssh2_pkt_send(ssh
, pktout
);
5885 static void ssh2_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
5887 static const char *const reasons
[] = {
5888 "<unknown reason code>",
5889 "Administratively prohibited",
5891 "Unknown channel type",
5892 "Resource shortage",
5894 unsigned i
= ssh_pkt_getuint32(pktin
);
5895 unsigned reason_code
;
5896 char *reason_string
;
5898 struct ssh_channel
*c
;
5899 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5901 return; /* nonexistent channel */
5902 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5903 return; /* dunno why they're failing this */
5905 reason_code
= ssh_pkt_getuint32(pktin
);
5906 if (reason_code
>= lenof(reasons
))
5907 reason_code
= 0; /* ensure reasons[reason_code] in range */
5908 ssh_pkt_getstring(pktin
, &reason_string
, &reason_length
);
5909 logeventf(ssh
, "Forwarded connection refused by server: %s [%.*s]",
5910 reasons
[reason_code
], reason_length
, reason_string
);
5912 pfd_close(c
->u
.pfd
.s
);
5914 del234(ssh
->channels
, c
);
5918 static void ssh2_msg_channel_request(Ssh ssh
, struct Packet
*pktin
)
5922 int typelen
, want_reply
;
5923 int reply
= SSH2_MSG_CHANNEL_FAILURE
; /* default */
5924 struct ssh_channel
*c
;
5925 struct Packet
*pktout
;
5927 localid
= ssh_pkt_getuint32(pktin
);
5928 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5929 want_reply
= ssh2_pkt_getbool(pktin
);
5932 * First, check that the channel exists. Otherwise,
5933 * we can instantly disconnect with a rude message.
5935 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
5938 sprintf(buf
, "Received channel request for nonexistent"
5939 " channel %d", localid
);
5941 pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5942 ssh2_pkt_adduint32(pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5943 ssh2_pkt_addstring(pktout
, buf
);
5944 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5945 ssh2_pkt_send_noqueue(ssh
, pktout
);
5946 connection_fatal(ssh
->frontend
, "%s", buf
);
5947 ssh
->close_expected
= TRUE
;
5948 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5953 * Having got the channel number, we now look at
5954 * the request type string to see if it's something
5957 if (c
== ssh
->mainchan
) {
5959 * We recognise "exit-status" and "exit-signal" on
5960 * the primary channel.
5962 if (typelen
== 11 &&
5963 !memcmp(type
, "exit-status", 11)) {
5965 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
5966 logeventf(ssh
, "Server sent command exit status %d",
5968 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5970 } else if (typelen
== 11 &&
5971 !memcmp(type
, "exit-signal", 11)) {
5973 int is_plausible
= TRUE
, is_int
= FALSE
;
5974 char *fmt_sig
= "", *fmt_msg
= "";
5976 int msglen
= 0, core
= FALSE
;
5977 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
5978 * provide an `int' for the signal, despite its
5979 * having been a `string' in the drafts since at
5980 * least 2001. (Fixed in session.c 1.147.) Try to
5981 * infer which we can safely parse it as. */
5983 unsigned char *p
= pktin
->body
+
5985 long len
= pktin
->length
- pktin
->savedpos
;
5986 unsigned long num
= GET_32BIT(p
); /* what is it? */
5987 /* If it's 0, it hardly matters; assume string */
5991 int maybe_int
= FALSE
, maybe_str
= FALSE
;
5992 #define CHECK_HYPOTHESIS(offset, result) \
5995 if (q >= 0 && q+4 <= len) { \
5996 q = q + 4 + GET_32BIT(p+q); \
5997 if (q >= 0 && q+4 <= len && \
5998 ((q = q + 4 + GET_32BIT(p+q))!= 0) && q == len) \
6002 CHECK_HYPOTHESIS(4+1, maybe_int
);
6003 CHECK_HYPOTHESIS(4+num
+1, maybe_str
);
6004 #undef CHECK_HYPOTHESIS
6005 if (maybe_int
&& !maybe_str
)
6007 else if (!maybe_int
&& maybe_str
)
6010 /* Crikey. Either or neither. Panic. */
6011 is_plausible
= FALSE
;
6016 /* Old non-standard OpenSSH. */
6017 int signum
= ssh_pkt_getuint32(pktin
);
6018 fmt_sig
= dupprintf(" %d", signum
);
6020 /* As per the drafts. */
6023 ssh_pkt_getstring(pktin
, &sig
, &siglen
);
6024 /* Signal name isn't supposed to be blank, but
6025 * let's cope gracefully if it is. */
6027 fmt_sig
= dupprintf(" \"%.*s\"",
6031 core
= ssh2_pkt_getbool(pktin
);
6032 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
6034 fmt_msg
= dupprintf(" (\"%.*s\")", msglen
, msg
);
6036 /* ignore lang tag */
6037 } /* else don't attempt to parse */
6038 logeventf(ssh
, "Server exited on signal%s%s%s",
6039 fmt_sig
, core ?
" (core dumped)" : "",
6041 if (*fmt_sig
) sfree(fmt_sig
);
6042 if (*fmt_msg
) sfree(fmt_msg
);
6043 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
6048 * This is a channel request we don't know
6049 * about, so we now either ignore the request
6050 * or respond with CHANNEL_FAILURE, depending
6053 reply
= SSH2_MSG_CHANNEL_FAILURE
;
6056 pktout
= ssh2_pkt_init(reply
);
6057 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6058 ssh2_pkt_send(ssh
, pktout
);
6062 static void ssh2_msg_global_request(Ssh ssh
, struct Packet
*pktin
)
6065 int typelen
, want_reply
;
6066 struct Packet
*pktout
;
6068 ssh_pkt_getstring(pktin
, &type
, &typelen
);
6069 want_reply
= ssh2_pkt_getbool(pktin
);
6072 * We currently don't support any global requests
6073 * at all, so we either ignore the request or
6074 * respond with REQUEST_FAILURE, depending on
6078 pktout
= ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
6079 ssh2_pkt_send(ssh
, pktout
);
6083 static void ssh2_msg_channel_open(Ssh ssh
, struct Packet
*pktin
)
6091 struct ssh_channel
*c
;
6092 unsigned remid
, winsize
, pktsize
;
6093 struct Packet
*pktout
;
6095 ssh_pkt_getstring(pktin
, &type
, &typelen
);
6096 c
= snew(struct ssh_channel
);
6099 remid
= ssh_pkt_getuint32(pktin
);
6100 winsize
= ssh_pkt_getuint32(pktin
);
6101 pktsize
= ssh_pkt_getuint32(pktin
);
6103 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
6106 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
6107 addrstr
= snewn(peeraddrlen
+1, char);
6108 memcpy(addrstr
, peeraddr
, peeraddrlen
);
6109 addrstr
[peeraddrlen
] = '\0';
6110 peerport
= ssh_pkt_getuint32(pktin
);
6112 logeventf(ssh
, "Received X11 connect request from %s:%d",
6115 if (!ssh
->X11_fwd_enabled
)
6116 error
= "X11 forwarding is not enabled";
6117 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
6118 ssh
->x11auth
, addrstr
, peerport
,
6119 &ssh
->cfg
) != NULL
) {
6120 error
= "Unable to open an X11 connection";
6122 logevent("Opening X11 forward connection succeeded");
6127 } else if (typelen
== 15 &&
6128 !memcmp(type
, "forwarded-tcpip", 15)) {
6129 struct ssh_rportfwd pf
, *realpf
;
6132 ssh_pkt_getstring(pktin
, &dummy
, &dummylen
);/* skip address */
6133 pf
.sport
= ssh_pkt_getuint32(pktin
);
6134 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
6135 peerport
= ssh_pkt_getuint32(pktin
);
6136 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
6137 logeventf(ssh
, "Received remote port %d open request "
6138 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
6139 if (realpf
== NULL
) {
6140 error
= "Remote port is not recognised";
6142 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
6146 realpf
->pfrec
->addressfamily
);
6147 logeventf(ssh
, "Attempting to forward remote port to "
6148 "%s:%d", realpf
->dhost
, realpf
->dport
);
6150 logeventf(ssh
, "Port open failed: %s", e
);
6151 error
= "Port open failed";
6153 logevent("Forwarded port opened successfully");
6154 c
->type
= CHAN_SOCKDATA
;
6157 } else if (typelen
== 22 &&
6158 !memcmp(type
, "auth-agent@openssh.com", 3)) {
6159 if (!ssh
->agentfwd_enabled
)
6160 error
= "Agent forwarding is not enabled";
6162 c
->type
= CHAN_AGENT
; /* identify channel type */
6163 c
->u
.a
.lensofar
= 0;
6166 error
= "Unsupported channel type requested";
6169 c
->remoteid
= remid
;
6170 c
->halfopen
= FALSE
;
6172 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
6173 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6174 ssh2_pkt_adduint32(pktout
, SSH2_OPEN_CONNECT_FAILED
);
6175 ssh2_pkt_addstring(pktout
, error
);
6176 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
6177 ssh2_pkt_send(ssh
, pktout
);
6178 logeventf(ssh
, "Rejected channel open: %s", error
);
6181 c
->localid
= alloc_channel_id(ssh
);
6183 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6184 c
->v
.v2
.remwindow
= winsize
;
6185 c
->v
.v2
.remmaxpkt
= pktsize
;
6186 bufchain_init(&c
->v
.v2
.outbuffer
);
6187 add234(ssh
->channels
, c
);
6188 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
6189 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6190 ssh2_pkt_adduint32(pktout
, c
->localid
);
6191 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);
6192 ssh2_pkt_adduint32(pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
6193 ssh2_pkt_send(ssh
, pktout
);
6198 * Handle the SSH-2 userauth and connection layers.
6200 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
6201 struct Packet
*pktin
)
6203 struct do_ssh2_authconn_state
{
6205 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
6207 AUTH_KEYBOARD_INTERACTIVE
6211 AUTH_TYPE_PUBLICKEY
,
6212 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
6213 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
6215 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
6216 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
6218 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
6219 int tried_pubkey_config
, tried_agent
;
6220 int kbd_inter_running
, kbd_inter_refused
;
6222 int num_prompts
, curr_prompt
, echo
;
6227 void *publickey_blob
;
6228 int publickey_bloblen
;
6229 unsigned char request
[5], *response
, *p
;
6233 char *pkblob
, *alg
, *commentp
;
6234 int pklen
, alglen
, commentlen
;
6235 int siglen
, retlen
, len
;
6236 char *q
, *agentreq
, *ret
;
6238 int num_env
, env_left
, env_ok
;
6239 struct Packet
*pktout
;
6241 crState(do_ssh2_authconn_state
);
6243 crBegin(ssh
->do_ssh2_authconn_crstate
);
6246 * Request userauth protocol, and await a response to it.
6248 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
6249 ssh2_pkt_addstring(s
->pktout
, "ssh-userauth");
6250 ssh2_pkt_send(ssh
, s
->pktout
);
6251 crWaitUntilV(pktin
);
6252 if (pktin
->type
!= SSH2_MSG_SERVICE_ACCEPT
) {
6253 bombout(("Server refused user authentication protocol"));
6258 * We repeat this whole loop, including the username prompt,
6259 * until we manage a successful authentication. If the user
6260 * types the wrong _password_, they can be sent back to the
6261 * beginning to try another username, if this is configured on.
6262 * (If they specify a username in the config, they are never
6263 * asked, even if they do give a wrong password.)
6265 * I think this best serves the needs of
6267 * - the people who have no configuration, no keys, and just
6268 * want to try repeated (username,password) pairs until they
6269 * type both correctly
6271 * - people who have keys and configuration but occasionally
6272 * need to fall back to passwords
6274 * - people with a key held in Pageant, who might not have
6275 * logged in to a particular machine before; so they want to
6276 * type a username, and then _either_ their key will be
6277 * accepted, _or_ they will type a password. If they mistype
6278 * the username they will want to be able to get back and
6281 s
->username
[0] = '\0';
6282 s
->got_username
= FALSE
;
6287 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
6289 * We got a username last time round this loop, and
6290 * with change_username turned off we don't try to get
6293 } else if (!*ssh
->cfg
.username
) {
6294 if (ssh_get_line
&& !ssh_getline_pw_only
) {
6295 if (!ssh_get_line("login as: ",
6296 s
->username
, sizeof(s
->username
), FALSE
)) {
6298 * get_line failed to get a username.
6301 logevent("No username provided. Abandoning session.");
6302 ssh
->close_expected
= TRUE
;
6303 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6307 int ret
; /* need not be saved across crReturn */
6308 c_write_str(ssh
, "login as: ");
6310 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
6312 crWaitUntilV(!pktin
);
6313 ret
= process_userpass_input(ssh
, in
, inlen
);
6317 c_write_str(ssh
, "\r\n");
6319 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
6322 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
6323 s
->username
[sizeof(s
->username
)-1] = '\0';
6324 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
6325 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
6326 c_write_str(ssh
, stuff
);
6330 s
->got_username
= TRUE
;
6333 * Send an authentication request using method "none": (a)
6334 * just in case it succeeds, and (b) so that we know what
6335 * authentication methods we can usefully try next.
6337 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6339 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6340 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6341 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");/* service requested */
6342 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6343 ssh2_pkt_send(ssh
, s
->pktout
);
6344 s
->type
= AUTH_TYPE_NONE
;
6346 s
->we_are_in
= FALSE
;
6348 s
->tried_pubkey_config
= FALSE
;
6349 s
->tried_agent
= FALSE
;
6350 s
->kbd_inter_running
= FALSE
;
6351 s
->kbd_inter_refused
= FALSE
;
6352 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
6353 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
6355 logeventf(ssh
, "Reading private key file \"%.150s\"",
6356 filename_to_str(&ssh
->cfg
.keyfile
));
6357 keytype
= key_type(&ssh
->cfg
.keyfile
);
6358 if (keytype
== SSH_KEYTYPE_SSH2
) {
6360 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
6361 &s
->publickey_bloblen
, NULL
);
6364 logeventf(ssh
, "Unable to use this key file (%s)",
6365 key_type_to_str(keytype
));
6366 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
6368 filename_to_str(&ssh
->cfg
.keyfile
),
6369 key_type_to_str(keytype
));
6370 c_write_str(ssh
, msgbuf
);
6372 s
->publickey_blob
= NULL
;
6375 s
->publickey_blob
= NULL
;
6379 * Wait for the result of the last authentication request.
6382 crWaitUntilV(pktin
);
6383 while (pktin
->type
== SSH2_MSG_USERAUTH_BANNER
) {
6387 * Don't show the banner if we're operating in
6388 * non-verbose non-interactive mode. (It's probably
6389 * a script, which means nobody will read the
6390 * banner _anyway_, and moreover the printing of
6391 * the banner will screw up processing on the
6392 * output of (say) plink.)
6394 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
6395 ssh_pkt_getstring(pktin
, &banner
, &size
);
6397 c_write_untrusted(ssh
, banner
, size
);
6399 crWaitUntilV(pktin
);
6401 if (pktin
->type
== SSH2_MSG_USERAUTH_SUCCESS
) {
6402 logevent("Access granted");
6403 s
->we_are_in
= TRUE
;
6407 if (s
->kbd_inter_running
&&
6408 pktin
->type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6410 * This is either a further set-of-prompts packet
6411 * in keyboard-interactive authentication, or it's
6412 * the same one and we came back here with `gotit'
6413 * set. In the former case, we must reset the
6414 * curr_prompt variable.
6418 } else if (pktin
->type
== SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
) {
6419 /* FIXME: perhaps we should support this? */
6420 bombout(("PASSWD_CHANGEREQ not yet supported"));
6422 } else if (pktin
->type
!= SSH2_MSG_USERAUTH_FAILURE
) {
6423 bombout(("Strange packet received during authentication: type %d",
6431 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6432 * we can look at the string in it and know what we can
6433 * helpfully try next.
6435 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
) {
6438 ssh_pkt_getstring(pktin
, &methods
, &methlen
);
6439 s
->kbd_inter_running
= FALSE
;
6440 if (!ssh2_pkt_getbool(pktin
)) {
6442 * We have received an unequivocal Access
6443 * Denied. This can translate to a variety of
6446 * - if we'd just tried "none" authentication,
6447 * it's not worth printing anything at all
6449 * - if we'd just tried a public key _offer_,
6450 * the message should be "Server refused our
6451 * key" (or no message at all if the key
6452 * came from Pageant)
6454 * - if we'd just tried anything else, the
6455 * message really should be "Access denied".
6457 * Additionally, if we'd just tried password
6458 * authentication, we should break out of this
6459 * whole loop so as to go back to the username
6460 * prompt (iff we're configured to allow
6461 * username change attempts).
6463 if (s
->type
== AUTH_TYPE_NONE
) {
6465 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
6466 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
6467 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
6468 c_write_str(ssh
, "Server refused our key\r\n");
6469 logevent("Server refused public key");
6470 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
6471 /* server declined keyboard-interactive; ignore */
6473 c_write_str(ssh
, "Access denied\r\n");
6474 logevent("Access denied");
6475 if (s
->type
== AUTH_TYPE_PASSWORD
&&
6476 ssh
->cfg
.change_username
) {
6477 /* XXX perhaps we should allow
6478 * keyboard-interactive to do this too? */
6479 s
->we_are_in
= FALSE
;
6484 c_write_str(ssh
, "Further authentication required\r\n");
6485 logevent("Further authentication required");
6489 in_commasep_string("publickey", methods
, methlen
);
6491 in_commasep_string("password", methods
, methlen
);
6492 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
6493 in_commasep_string("keyboard-interactive", methods
, methlen
);
6497 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6501 * Most password/passphrase prompts will be
6502 * non-echoing, so we set this to 0 by default.
6503 * Exception is that some keyboard-interactive prompts
6504 * can be echoing, in which case we'll set this to 1.
6508 if (!s
->method
&& s
->can_pubkey
&&
6509 agent_exists() && !s
->tried_agent
) {
6511 * Attempt public-key authentication using Pageant.
6516 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6517 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6519 s
->tried_agent
= TRUE
;
6521 logevent("Pageant is running. Requesting keys.");
6523 /* Request the keys held by the agent. */
6524 PUT_32BIT(s
->request
, 1);
6525 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
6526 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
6527 ssh_agent_callback
, ssh
)) {
6531 bombout(("Unexpected data from server while"
6532 " waiting for agent response"));
6535 } while (pktin
|| inlen
> 0);
6536 r
= ssh
->agent_response
;
6537 s
->responselen
= ssh
->agent_response_len
;
6539 s
->response
= (unsigned char *) r
;
6540 if (s
->response
&& s
->responselen
>= 5 &&
6541 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
6542 s
->p
= s
->response
+ 5;
6543 s
->nkeys
= GET_32BIT(s
->p
);
6545 logeventf(ssh
, "Pageant has %d SSH-2 keys", s
->nkeys
);
6546 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
6549 logeventf(ssh
, "Trying Pageant key #%d", s
->keyi
);
6550 s
->pklen
= GET_32BIT(s
->p
);
6552 if (s
->publickey_blob
&&
6553 s
->pklen
== s
->publickey_bloblen
&&
6554 !memcmp(s
->p
, s
->publickey_blob
,
6555 s
->publickey_bloblen
)) {
6556 logevent("This key matches configured key file");
6557 s
->tried_pubkey_config
= 1;
6559 s
->pkblob
= (char *)s
->p
;
6561 s
->alglen
= GET_32BIT(s
->pkblob
);
6562 s
->alg
= s
->pkblob
+ 4;
6563 s
->commentlen
= GET_32BIT(s
->p
);
6565 s
->commentp
= (char *)s
->p
;
6566 s
->p
+= s
->commentlen
;
6567 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6568 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6569 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6570 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6571 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6572 ssh2_pkt_addstring_start(s
->pktout
);
6573 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6574 ssh2_pkt_addstring_start(s
->pktout
);
6575 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6576 ssh2_pkt_send(ssh
, s
->pktout
);
6578 crWaitUntilV(pktin
);
6579 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6580 logevent("Key refused");
6584 if (flags
& FLAG_VERBOSE
) {
6585 c_write_str(ssh
, "Authenticating with "
6587 c_write(ssh
, s
->commentp
, s
->commentlen
);
6588 c_write_str(ssh
, "\" from agent\r\n");
6592 * Server is willing to accept the key.
6593 * Construct a SIGN_REQUEST.
6595 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6596 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6597 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6598 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6599 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6600 ssh2_pkt_addstring_start(s
->pktout
);
6601 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6602 ssh2_pkt_addstring_start(s
->pktout
);
6603 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6605 s
->siglen
= s
->pktout
->length
- 5 + 4 + 20;
6606 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6608 s
->len
= 1; /* message type */
6609 s
->len
+= 4 + s
->pklen
; /* key blob */
6610 s
->len
+= 4 + s
->siglen
; /* data to sign */
6611 s
->len
+= 4; /* flags */
6612 s
->agentreq
= snewn(4 + s
->len
, char);
6613 PUT_32BIT(s
->agentreq
, s
->len
);
6614 s
->q
= s
->agentreq
+ 4;
6615 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
6616 PUT_32BIT(s
->q
, s
->pklen
);
6618 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
6620 PUT_32BIT(s
->q
, s
->siglen
);
6622 /* Now the data to be signed... */
6623 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6624 PUT_32BIT(s
->q
, 20);
6627 memcpy(s
->q
, ssh
->v2_session_id
, 20);
6629 memcpy(s
->q
, s
->pktout
->data
+ 5,
6630 s
->pktout
->length
- 5);
6631 s
->q
+= s
->pktout
->length
- 5;
6632 /* And finally the (zero) flags word. */
6634 if (!agent_query(s
->agentreq
, s
->len
+ 4,
6636 ssh_agent_callback
, ssh
)) {
6640 bombout(("Unexpected data from server"
6641 " while waiting for agent"
6645 } while (pktin
|| inlen
> 0);
6646 vret
= ssh
->agent_response
;
6647 s
->retlen
= ssh
->agent_response_len
;
6652 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
6653 logevent("Sending Pageant's response");
6654 ssh2_add_sigblob(ssh
, s
->pktout
,
6655 s
->pkblob
, s
->pklen
,
6657 GET_32BIT(s
->ret
+ 5));
6658 ssh2_pkt_send(ssh
, s
->pktout
);
6663 ("Pageant failed to answer challenge");
6674 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
6675 && !s
->tried_pubkey_config
) {
6676 unsigned char *pub_blob
;
6677 char *algorithm
, *comment
;
6680 s
->tried_pubkey_config
= TRUE
;
6682 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6683 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6686 * Try the public key supplied in the configuration.
6688 * First, offer the public blob to see if the server is
6689 * willing to accept it.
6692 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
6697 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6698 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6699 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6700 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6701 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6702 ssh2_pkt_addstring(s
->pktout
, algorithm
);
6703 ssh2_pkt_addstring_start(s
->pktout
);
6704 ssh2_pkt_addstring_data(s
->pktout
, (char *)pub_blob
,
6706 ssh2_pkt_send(ssh
, s
->pktout
);
6707 logevent("Offered public key");
6709 crWaitUntilV(pktin
);
6710 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6712 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
6713 continue; /* key refused; give up on it */
6716 logevent("Offer of public key accepted");
6718 * Actually attempt a serious authentication using
6721 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
6722 sprintf(s
->pwprompt
,
6723 "Passphrase for key \"%.100s\": ",
6729 if (flags
& FLAG_VERBOSE
) {
6730 c_write_str(ssh
, "Authenticating with public key \"");
6731 c_write_str(ssh
, comment
);
6732 c_write_str(ssh
, "\"\r\n");
6734 s
->method
= AUTH_PUBLICKEY_FILE
;
6738 if (!s
->method
&& s
->can_keyb_inter
&& !s
->kbd_inter_refused
&&
6739 !s
->kbd_inter_running
) {
6740 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6741 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6743 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6744 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6746 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6747 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6748 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6749 ssh2_pkt_addstring(s
->pktout
, "keyboard-interactive"); /* method */
6750 ssh2_pkt_addstring(s
->pktout
, ""); /* lang */
6751 ssh2_pkt_addstring(s
->pktout
, "");
6752 ssh2_pkt_send(ssh
, s
->pktout
);
6754 crWaitUntilV(pktin
);
6755 if (pktin
->type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6756 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
)
6758 logevent("Keyboard-interactive authentication refused");
6759 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
6760 s
->kbd_inter_refused
= TRUE
; /* don't try it again */
6764 c_write_str(ssh
, "Using keyboard-interactive authentication.\r\n");
6765 s
->kbd_inter_running
= TRUE
;
6769 if (s
->kbd_inter_running
) {
6770 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6771 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6773 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6774 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6776 if (s
->curr_prompt
== 0) {
6778 * We've got a fresh USERAUTH_INFO_REQUEST.
6779 * Display header data, and start going through
6782 char *name
, *inst
, *lang
;
6783 int name_len
, inst_len
, lang_len
;
6785 ssh_pkt_getstring(pktin
, &name
, &name_len
);
6786 ssh_pkt_getstring(pktin
, &inst
, &inst_len
);
6787 ssh_pkt_getstring(pktin
, &lang
, &lang_len
);
6789 c_write_untrusted(ssh
, name
, name_len
);
6790 c_write_str(ssh
, "\r\n");
6793 c_write_untrusted(ssh
, inst
, inst_len
);
6794 c_write_str(ssh
, "\r\n");
6796 s
->num_prompts
= ssh_pkt_getuint32(pktin
);
6800 * If there are prompts remaining in the packet,
6801 * display one and get a response.
6803 if (s
->curr_prompt
< s
->num_prompts
) {
6807 ssh_pkt_getstring(pktin
, &prompt
, &prompt_len
);
6808 if (prompt_len
> 0) {
6809 static const char trunc
[] = "<prompt truncated>: ";
6810 static const int prlen
= sizeof(s
->pwprompt
) -
6812 if (prompt_len
> prlen
) {
6813 memcpy(s
->pwprompt
, prompt
, prlen
);
6814 strcpy(s
->pwprompt
+ prlen
, trunc
);
6816 memcpy(s
->pwprompt
, prompt
, prompt_len
);
6817 s
->pwprompt
[prompt_len
] = '\0';
6821 "<server failed to send prompt>: ");
6823 s
->echo
= ssh2_pkt_getbool(pktin
);
6829 if (!s
->method
&& s
->can_passwd
) {
6830 s
->method
= AUTH_PASSWORD
;
6831 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6832 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
6833 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
6840 if (!ssh_get_line(s
->pwprompt
, s
->password
,
6841 sizeof(s
->password
), TRUE
)) {
6843 * get_line failed to get a password (for
6844 * example because one was supplied on the
6845 * command line which has already failed to
6848 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6849 ssh2_pkt_adduint32(s
->pktout
,SSH2_DISCONNECT_BY_APPLICATION
);
6850 ssh2_pkt_addstring(s
->pktout
, "No more passwords available"
6852 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6853 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6854 logevent("Unable to authenticate");
6855 connection_fatal(ssh
->frontend
,
6856 "Unable to authenticate");
6857 ssh
->close_expected
= TRUE
;
6858 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6862 int ret
; /* need not be saved across crReturn */
6863 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
6866 setup_userpass_input(ssh
, s
->password
,
6867 sizeof(s
->password
), s
->echo
);
6869 crWaitUntilV(!pktin
);
6870 ret
= process_userpass_input(ssh
, in
, inlen
);
6874 c_write_str(ssh
, "\r\n");
6878 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
6880 * We have our passphrase. Now try the actual authentication.
6882 struct ssh2_userkey
*key
;
6883 const char *error
= NULL
;
6885 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
,
6887 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
6888 if (key
== SSH2_WRONG_PASSPHRASE
) {
6889 c_write_str(ssh
, "Wrong passphrase\r\n");
6890 s
->tried_pubkey_config
= FALSE
;
6892 c_write_str(ssh
, "Unable to load private key (");
6893 c_write_str(ssh
, error
);
6894 c_write_str(ssh
, ")\r\n");
6895 s
->tried_pubkey_config
= TRUE
;
6897 /* Send a spurious AUTH_NONE to return to the top. */
6898 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6899 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6900 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6901 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6902 ssh2_pkt_send(ssh
, s
->pktout
);
6903 s
->type
= AUTH_TYPE_NONE
;
6905 unsigned char *pkblob
, *sigblob
, *sigdata
;
6906 int pkblob_len
, sigblob_len
, sigdata_len
;
6910 * We have loaded the private key and the server
6911 * has announced that it's willing to accept it.
6912 * Hallelujah. Generate a signature and send it.
6914 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6915 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6916 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6917 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6918 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6919 ssh2_pkt_addstring(s
->pktout
, key
->alg
->name
);
6920 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
6921 ssh2_pkt_addstring_start(s
->pktout
);
6922 ssh2_pkt_addstring_data(s
->pktout
, (char *)pkblob
, pkblob_len
);
6925 * The data to be signed is:
6929 * followed by everything so far placed in the
6932 sigdata_len
= s
->pktout
->length
- 5 + 4 + 20;
6933 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6935 sigdata
= snewn(sigdata_len
, unsigned char);
6937 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6938 PUT_32BIT(sigdata
+p
, 20);
6941 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
6942 memcpy(sigdata
+p
, s
->pktout
->data
+ 5,
6943 s
->pktout
->length
- 5);
6944 p
+= s
->pktout
->length
- 5;
6945 assert(p
== sigdata_len
);
6946 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
6947 sigdata_len
, &sigblob_len
);
6948 ssh2_add_sigblob(ssh
, s
->pktout
, pkblob
, pkblob_len
,
6949 sigblob
, sigblob_len
);
6954 ssh2_pkt_send(ssh
, s
->pktout
);
6955 s
->type
= AUTH_TYPE_PUBLICKEY
;
6956 key
->alg
->freekey(key
->data
);
6958 } else if (s
->method
== AUTH_PASSWORD
) {
6960 * We pad out the password packet to 256 bytes to make
6961 * it harder for an attacker to find the length of the
6964 * Anyone using a password longer than 256 bytes
6965 * probably doesn't have much to worry about from
6966 * people who find out how long their password is!
6968 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6969 s
->pktout
->forcepad
= 256;
6970 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6971 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6972 ssh2_pkt_addstring(s
->pktout
, "password");
6973 ssh2_pkt_addbool(s
->pktout
, FALSE
);
6974 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6975 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6976 memset(s
->password
, 0, sizeof(s
->password
));
6977 end_log_omission(ssh
, s
->pktout
);
6978 ssh2_pkt_send(ssh
, s
->pktout
);
6979 logevent("Sent password");
6980 s
->type
= AUTH_TYPE_PASSWORD
;
6981 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
6982 if (s
->curr_prompt
== 0) {
6983 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
6984 s
->pktout
->forcepad
= 256;
6985 ssh2_pkt_adduint32(s
->pktout
, s
->num_prompts
);
6987 if (s
->need_pw
) { /* only add pw if we just got one! */
6988 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6989 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6990 memset(s
->password
, 0, sizeof(s
->password
));
6991 end_log_omission(ssh
, s
->pktout
);
6994 if (s
->curr_prompt
>= s
->num_prompts
) {
6995 ssh2_pkt_send(ssh
, s
->pktout
);
6998 * If there are prompts remaining, we set
6999 * `gotit' so that we won't attempt to get
7000 * another packet. Then we go back round the
7001 * loop and will end up retrieving another
7002 * prompt out of the existing packet. Funky or
7007 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
7009 c_write_str(ssh
, "No supported authentication methods"
7010 " left to try!\r\n");
7011 logevent("No supported authentications offered."
7013 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
7014 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
7015 ssh2_pkt_addstring(s
->pktout
, "No supported authentication"
7016 " methods available");
7017 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
7018 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
7019 ssh
->close_expected
= TRUE
;
7020 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
7024 } while (!s
->we_are_in
);
7027 * Now we're authenticated for the connection protocol. The
7028 * connection protocol will automatically have started at this
7029 * point; there's no need to send SERVICE_REQUEST.
7032 ssh
->channels
= newtree234(ssh_channelcmp
);
7035 * Set up handlers for some connection protocol messages, so we
7036 * don't have to handle them repeatedly in this coroutine.
7038 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] =
7039 ssh2_msg_channel_window_adjust
;
7040 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] =
7041 ssh2_msg_global_request
;
7044 * Create the main session channel.
7046 if (!ssh
->cfg
.ssh_no_shell
) {
7047 ssh
->mainchan
= snew(struct ssh_channel
);
7048 ssh
->mainchan
->ssh
= ssh
;
7049 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
7050 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
7051 ssh2_pkt_addstring(s
->pktout
, "session");
7052 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->localid
);
7053 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7054 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
7055 ssh2_pkt_adduint32(s
->pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
7056 ssh2_pkt_send(ssh
, s
->pktout
);
7057 crWaitUntilV(pktin
);
7058 if (pktin
->type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
7059 bombout(("Server refused to open a session"));
7061 /* FIXME: error data comes back in FAILURE packet */
7063 if (ssh_pkt_getuint32(pktin
) != ssh
->mainchan
->localid
) {
7064 bombout(("Server's channel confirmation cited wrong channel"));
7067 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(pktin
);
7068 ssh
->mainchan
->halfopen
= FALSE
;
7069 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
7070 ssh
->mainchan
->closes
= 0;
7071 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
7072 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
7073 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
7074 add234(ssh
->channels
, ssh
->mainchan
);
7075 update_specials_menu(ssh
->frontend
);
7076 logevent("Opened channel for session");
7078 ssh
->mainchan
= NULL
;
7081 * Now we have a channel, make dispatch table entries for
7082 * general channel-based messages.
7084 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] =
7085 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] =
7086 ssh2_msg_channel_data
;
7087 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = ssh2_msg_channel_eof
;
7088 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = ssh2_msg_channel_close
;
7089 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] =
7090 ssh2_msg_channel_open_confirmation
;
7091 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] =
7092 ssh2_msg_channel_open_failure
;
7093 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] =
7094 ssh2_msg_channel_request
;
7095 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] =
7096 ssh2_msg_channel_open
;
7099 * Potentially enable X11 forwarding.
7101 if (ssh
->mainchan
&& ssh
->cfg
.x11_forward
) {
7102 char proto
[20], data
[64];
7103 logevent("Requesting X11 forwarding");
7104 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
7105 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
7106 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
7107 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7108 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7109 ssh2_pkt_addstring(s
->pktout
, "x11-req");
7110 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7111 ssh2_pkt_addbool(s
->pktout
, 0); /* many connections */
7112 ssh2_pkt_addstring(s
->pktout
, proto
);
7113 ssh2_pkt_addstring(s
->pktout
, data
);
7114 ssh2_pkt_adduint32(s
->pktout
, x11_get_screen_number(ssh
->cfg
.x11_display
));
7115 ssh2_pkt_send(ssh
, s
->pktout
);
7117 crWaitUntilV(pktin
);
7119 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7120 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7121 bombout(("Unexpected response to X11 forwarding request:"
7122 " packet type %d", pktin
->type
));
7125 logevent("X11 forwarding refused");
7127 logevent("X11 forwarding enabled");
7128 ssh
->X11_fwd_enabled
= TRUE
;
7133 * Enable port forwardings.
7135 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
7138 * Potentially enable agent forwarding.
7140 if (ssh
->mainchan
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
7141 logevent("Requesting OpenSSH-style agent forwarding");
7142 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7143 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7144 ssh2_pkt_addstring(s
->pktout
, "auth-agent-req@openssh.com");
7145 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7146 ssh2_pkt_send(ssh
, s
->pktout
);
7148 crWaitUntilV(pktin
);
7150 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7151 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7152 bombout(("Unexpected response to agent forwarding request:"
7153 " packet type %d", pktin
->type
));
7156 logevent("Agent forwarding refused");
7158 logevent("Agent forwarding enabled");
7159 ssh
->agentfwd_enabled
= TRUE
;
7164 * Now allocate a pty for the session.
7166 if (ssh
->mainchan
&& !ssh
->cfg
.nopty
) {
7167 /* Unpick the terminal-speed string. */
7168 /* XXX perhaps we should allow no speeds to be sent. */
7169 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
7170 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
7171 /* Build the pty request. */
7172 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7173 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7174 ssh2_pkt_addstring(s
->pktout
, "pty-req");
7175 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7176 ssh2_pkt_addstring(s
->pktout
, ssh
->cfg
.termtype
);
7177 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_width
);
7178 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_height
);
7179 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel width */
7180 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel height */
7181 ssh2_pkt_addstring_start(s
->pktout
);
7182 ssh2_pkt_addbyte(s
->pktout
, 128); /* TTY_OP_ISPEED */
7183 ssh2_pkt_adduint32(s
->pktout
, ssh
->ispeed
);
7184 ssh2_pkt_addbyte(s
->pktout
, 129); /* TTY_OP_OSPEED */
7185 ssh2_pkt_adduint32(s
->pktout
, ssh
->ospeed
);
7186 ssh2_pkt_addstring_data(s
->pktout
, "\0", 1); /* TTY_OP_END */
7187 ssh2_pkt_send(ssh
, s
->pktout
);
7188 ssh
->state
= SSH_STATE_INTERMED
;
7190 crWaitUntilV(pktin
);
7192 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7193 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7194 bombout(("Unexpected response to pty request:"
7195 " packet type %d", pktin
->type
));
7198 c_write_str(ssh
, "Server refused to allocate pty\r\n");
7199 ssh
->editing
= ssh
->echoing
= 1;
7201 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
7202 ssh
->ospeed
, ssh
->ispeed
);
7205 ssh
->editing
= ssh
->echoing
= 1;
7209 * Send environment variables.
7211 * Simplest thing here is to send all the requests at once, and
7212 * then wait for a whole bunch of successes or failures.
7214 if (ssh
->mainchan
&& *ssh
->cfg
.environmt
) {
7215 char *e
= ssh
->cfg
.environmt
;
7216 char *var
, *varend
, *val
;
7222 while (*e
&& *e
!= '\t') e
++;
7224 if (*e
== '\t') e
++;
7229 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7230 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7231 ssh2_pkt_addstring(s
->pktout
, "env");
7232 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7233 ssh2_pkt_addstring_start(s
->pktout
);
7234 ssh2_pkt_addstring_data(s
->pktout
, var
, varend
-var
);
7235 ssh2_pkt_addstring(s
->pktout
, val
);
7236 ssh2_pkt_send(ssh
, s
->pktout
);
7241 logeventf(ssh
, "Sent %d environment variables", s
->num_env
);
7244 s
->env_left
= s
->num_env
;
7246 while (s
->env_left
> 0) {
7247 crWaitUntilV(pktin
);
7249 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7250 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7251 bombout(("Unexpected response to environment request:"
7252 " packet type %d", pktin
->type
));
7262 if (s
->env_ok
== s
->num_env
) {
7263 logevent("All environment variables successfully set");
7264 } else if (s
->env_ok
== 0) {
7265 logevent("All environment variables refused");
7266 c_write_str(ssh
, "Server refused to set environment variables\r\n");
7268 logeventf(ssh
, "%d environment variables refused",
7269 s
->num_env
- s
->env_ok
);
7270 c_write_str(ssh
, "Server refused to set all environment variables\r\n");
7275 * Start a shell or a remote command. We may have to attempt
7276 * this twice if the config data has provided a second choice
7279 if (ssh
->mainchan
) while (1) {
7283 if (ssh
->fallback_cmd
) {
7284 subsys
= ssh
->cfg
.ssh_subsys2
;
7285 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
7287 subsys
= ssh
->cfg
.ssh_subsys
;
7288 cmd
= ssh
->cfg
.remote_cmd_ptr
;
7289 if (!cmd
) cmd
= ssh
->cfg
.remote_cmd
;
7292 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7293 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7295 ssh2_pkt_addstring(s
->pktout
, "subsystem");
7296 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7297 ssh2_pkt_addstring(s
->pktout
, cmd
);
7299 ssh2_pkt_addstring(s
->pktout
, "exec");
7300 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7301 ssh2_pkt_addstring(s
->pktout
, cmd
);
7303 ssh2_pkt_addstring(s
->pktout
, "shell");
7304 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7306 ssh2_pkt_send(ssh
, s
->pktout
);
7308 crWaitUntilV(pktin
);
7310 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7311 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7312 bombout(("Unexpected response to shell/command request:"
7313 " packet type %d", pktin
->type
));
7317 * We failed to start the command. If this is the
7318 * fallback command, we really are finished; if it's
7319 * not, and if the fallback command exists, try falling
7320 * back to it before complaining.
7322 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
7323 logevent("Primary command failed; attempting fallback");
7324 ssh
->fallback_cmd
= TRUE
;
7327 bombout(("Server refused to start a shell/command"));
7330 logevent("Started a shell/command");
7335 ssh
->state
= SSH_STATE_SESSION
;
7336 if (ssh
->size_needed
)
7337 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
7338 if (ssh
->eof_needed
)
7339 ssh_special(ssh
, TS_EOF
);
7345 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
7350 s
->try_send
= FALSE
;
7354 * _All_ the connection-layer packets we expect to
7355 * receive are now handled by the dispatch table.
7356 * Anything that reaches here must be bogus.
7359 bombout(("Strange packet received: type %d", pktin
->type
));
7361 } else if (ssh
->mainchan
) {
7363 * We have spare data. Add it to the channel buffer.
7365 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
7370 struct ssh_channel
*c
;
7372 * Try to send data on all channels if we can.
7374 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++)
7375 ssh2_try_send_and_unthrottle(c
);
7383 * Handlers for SSH-2 messages that might arrive at any moment.
7385 static void ssh2_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
7387 /* log reason code in disconnect message */
7389 int nowlen
, reason
, msglen
;
7391 reason
= ssh_pkt_getuint32(pktin
);
7392 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7394 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
7395 buf
= dupprintf("Received disconnect message (%s)",
7396 ssh2_disconnect_reasons
[reason
]);
7398 buf
= dupprintf("Received disconnect message (unknown"
7399 " type %d)", reason
);
7403 buf
= dupprintf("Disconnection message text: %n%.*s",
7404 &nowlen
, msglen
, msg
);
7406 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7408 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
7409 ssh2_disconnect_reasons
[reason
] : "unknown",
7414 static void ssh2_msg_debug(Ssh ssh
, struct Packet
*pktin
)
7416 /* log the debug message */
7421 /* XXX maybe we should actually take notice of this */
7422 always_display
= ssh2_pkt_getbool(pktin
);
7423 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7425 logeventf(ssh
, "Remote debug message: %.*s", msglen
, msg
);
7428 static void ssh2_msg_something_unimplemented(Ssh ssh
, struct Packet
*pktin
)
7430 struct Packet
*pktout
;
7431 pktout
= ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
7432 ssh2_pkt_adduint32(pktout
, pktin
->sequence
);
7434 * UNIMPLEMENTED messages MUST appear in the same order as the
7435 * messages they respond to. Hence, never queue them.
7437 ssh2_pkt_send_noqueue(ssh
, pktout
);
7441 * Handle the top-level SSH-2 protocol.
7443 static void ssh2_protocol_setup(Ssh ssh
)
7448 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7450 for (i
= 0; i
< 256; i
++)
7451 ssh
->packet_dispatch
[i
] = ssh2_msg_something_unimplemented
;
7454 * Any message we actually understand, we set to NULL so that
7455 * the coroutines will get it.
7457 ssh
->packet_dispatch
[SSH2_MSG_UNIMPLEMENTED
] = NULL
;
7458 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_REQUEST
] = NULL
;
7459 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_ACCEPT
] = NULL
;
7460 ssh
->packet_dispatch
[SSH2_MSG_KEXINIT
] = NULL
;
7461 ssh
->packet_dispatch
[SSH2_MSG_NEWKEYS
] = NULL
;
7462 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_INIT
] = NULL
;
7463 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_REPLY
] = NULL
;
7464 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7465 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7466 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_INIT
] = NULL
;
7467 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_REPLY
] = NULL
;
7468 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_REQUEST
] = NULL
;
7469 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_FAILURE
] = NULL
;
7470 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_SUCCESS
] = NULL
;
7471 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
7472 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_PK_OK
] = NULL
;
7473 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7474 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7475 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_INFO_RESPONSE
] = NULL
;
7476 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] = NULL
;
7477 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_SUCCESS
] = NULL
;
7478 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_FAILURE
] = NULL
;
7479 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] = NULL
;
7480 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] = NULL
;
7481 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] = NULL
;
7482 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] = NULL
;
7483 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] = NULL
;
7484 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] = NULL
;
7485 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = NULL
;
7486 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = NULL
;
7487 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] = NULL
;
7488 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_SUCCESS
] = NULL
;
7489 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_FAILURE
] = NULL
;
7492 * These special message types we install handlers for.
7494 ssh
->packet_dispatch
[SSH2_MSG_DISCONNECT
] = ssh2_msg_disconnect
;
7495 ssh
->packet_dispatch
[SSH2_MSG_IGNORE
] = ssh_msg_ignore
; /* shared with SSH-1 */
7496 ssh
->packet_dispatch
[SSH2_MSG_DEBUG
] = ssh2_msg_debug
;
7499 static void ssh2_timer(void *ctx
, long now
)
7503 if (ssh
->state
== SSH_STATE_CLOSED
)
7506 if (!ssh
->kex_in_progress
&& ssh
->cfg
.ssh_rekey_time
!= 0 &&
7507 now
- ssh
->next_rekey
>= 0) {
7508 do_ssh2_transport(ssh
, "timeout", -1, NULL
);
7512 static void ssh2_protocol(Ssh ssh
, void *vin
, int inlen
,
7513 struct Packet
*pktin
)
7515 unsigned char *in
= (unsigned char *)vin
;
7516 if (ssh
->state
== SSH_STATE_CLOSED
)
7520 ssh
->incoming_data_size
+= pktin
->encrypted_len
;
7521 if (!ssh
->kex_in_progress
&&
7522 ssh
->max_data_size
!= 0 &&
7523 ssh
->incoming_data_size
> ssh
->max_data_size
)
7524 do_ssh2_transport(ssh
, "too much data received", -1, NULL
);
7527 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
7528 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
7532 if (!ssh
->protocol_initial_phase_done
||
7533 (pktin
&& pktin
->type
>= 20 && pktin
->type
< 50)) {
7534 if (do_ssh2_transport(ssh
, in
, inlen
, pktin
) &&
7535 !ssh
->protocol_initial_phase_done
) {
7536 ssh
->protocol_initial_phase_done
= TRUE
;
7538 * Allow authconn to initialise itself.
7540 do_ssh2_authconn(ssh
, NULL
, 0, NULL
);
7543 do_ssh2_authconn(ssh
, in
, inlen
, pktin
);
7548 * Called to set up the connection.
7550 * Returns an error message, or NULL on success.
7552 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
7554 char *host
, int port
, char **realhost
, int nodelay
,
7560 ssh
= snew(struct ssh_tag
);
7561 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7562 ssh
->version
= 0; /* when not ready yet */
7565 ssh
->v1_cipher_ctx
= NULL
;
7566 ssh
->crcda_ctx
= NULL
;
7567 ssh
->cscipher
= NULL
;
7568 ssh
->cs_cipher_ctx
= NULL
;
7569 ssh
->sccipher
= NULL
;
7570 ssh
->sc_cipher_ctx
= NULL
;
7572 ssh
->cs_mac_ctx
= NULL
;
7574 ssh
->sc_mac_ctx
= NULL
;
7576 ssh
->cs_comp_ctx
= NULL
;
7578 ssh
->sc_comp_ctx
= NULL
;
7580 ssh
->kex_ctx
= NULL
;
7581 ssh
->hostkey
= NULL
;
7583 ssh
->close_expected
= FALSE
;
7584 ssh
->state
= SSH_STATE_PREPACKET
;
7585 ssh
->size_needed
= FALSE
;
7586 ssh
->eof_needed
= FALSE
;
7589 ssh
->deferred_send_data
= NULL
;
7590 ssh
->deferred_len
= 0;
7591 ssh
->deferred_size
= 0;
7592 ssh
->fallback_cmd
= 0;
7594 ssh
->x11auth
= NULL
;
7595 ssh
->v1_compressing
= FALSE
;
7596 ssh
->v2_outgoing_sequence
= 0;
7597 ssh
->ssh1_rdpkt_crstate
= 0;
7598 ssh
->ssh2_rdpkt_crstate
= 0;
7599 ssh
->do_ssh_init_crstate
= 0;
7600 ssh
->ssh_gotdata_crstate
= 0;
7601 ssh
->do_ssh1_connection_crstate
= 0;
7602 ssh
->do_ssh1_login_crstate
= 0;
7603 ssh
->do_ssh2_transport_crstate
= 0;
7604 ssh
->do_ssh2_authconn_crstate
= 0;
7605 ssh
->do_ssh_init_state
= NULL
;
7606 ssh
->do_ssh1_login_state
= NULL
;
7607 ssh
->do_ssh2_transport_state
= NULL
;
7608 ssh
->do_ssh2_authconn_state
= NULL
;
7609 ssh
->mainchan
= NULL
;
7610 ssh
->throttled_all
= 0;
7611 ssh
->v1_stdout_throttling
= 0;
7613 ssh
->queuelen
= ssh
->queuesize
= 0;
7614 ssh
->queueing
= FALSE
;
7615 ssh
->qhead
= ssh
->qtail
= NULL
;
7616 ssh
->deferred_rekey_reason
= NULL
;
7617 bufchain_init(&ssh
->queued_incoming_data
);
7618 ssh
->frozen
= FALSE
;
7620 *backend_handle
= ssh
;
7623 if (crypto_startup() == 0)
7624 return "Microsoft high encryption pack not installed!";
7627 ssh
->frontend
= frontend_handle
;
7628 ssh
->term_width
= ssh
->cfg
.width
;
7629 ssh
->term_height
= ssh
->cfg
.height
;
7631 ssh
->channels
= NULL
;
7632 ssh
->rportfwds
= NULL
;
7633 ssh
->portfwds
= NULL
;
7638 ssh
->v1_throttle_count
= 0;
7639 ssh
->overall_bufsize
= 0;
7640 ssh
->fallback_cmd
= 0;
7642 ssh
->protocol
= NULL
;
7644 ssh
->protocol_initial_phase_done
= FALSE
;
7648 ssh
->incoming_data_size
= ssh
->outgoing_data_size
=
7649 ssh
->deferred_data_size
= 0L;
7650 ssh
->max_data_size
= parse_blocksize(ssh
->cfg
.ssh_rekey_data
);
7651 ssh
->kex_in_progress
= FALSE
;
7653 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
7662 static void ssh_free(void *handle
)
7664 Ssh ssh
= (Ssh
) handle
;
7665 struct ssh_channel
*c
;
7666 struct ssh_rportfwd
*pf
;
7668 if (ssh
->v1_cipher_ctx
)
7669 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
7670 if (ssh
->cs_cipher_ctx
)
7671 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
7672 if (ssh
->sc_cipher_ctx
)
7673 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
7674 if (ssh
->cs_mac_ctx
)
7675 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
7676 if (ssh
->sc_mac_ctx
)
7677 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
7678 if (ssh
->cs_comp_ctx
) {
7680 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
7682 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
7684 if (ssh
->sc_comp_ctx
) {
7686 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
7688 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
7691 dh_cleanup(ssh
->kex_ctx
);
7692 sfree(ssh
->savedhost
);
7694 while (ssh
->queuelen
-- > 0)
7695 ssh_free_packet(ssh
->queue
[ssh
->queuelen
]);
7698 while (ssh
->qhead
) {
7699 struct queued_handler
*qh
= ssh
->qhead
;
7700 ssh
->qhead
= qh
->next
;
7703 ssh
->qhead
= ssh
->qtail
= NULL
;
7705 if (ssh
->channels
) {
7706 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
7709 if (c
->u
.x11
.s
!= NULL
)
7710 x11_close(c
->u
.x11
.s
);
7713 if (c
->u
.pfd
.s
!= NULL
)
7714 pfd_close(c
->u
.pfd
.s
);
7719 freetree234(ssh
->channels
);
7720 ssh
->channels
= NULL
;
7723 if (ssh
->rportfwds
) {
7724 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
7726 freetree234(ssh
->rportfwds
);
7727 ssh
->rportfwds
= NULL
;
7729 sfree(ssh
->deferred_send_data
);
7731 x11_free_auth(ssh
->x11auth
);
7732 sfree(ssh
->do_ssh_init_state
);
7733 sfree(ssh
->do_ssh1_login_state
);
7734 sfree(ssh
->do_ssh2_transport_state
);
7735 sfree(ssh
->do_ssh2_authconn_state
);
7736 if (ssh
->crcda_ctx
) {
7737 crcda_free_context(ssh
->crcda_ctx
);
7738 ssh
->crcda_ctx
= NULL
;
7741 ssh_do_close(ssh
, TRUE
);
7742 expire_timer_context(ssh
);
7744 pinger_free(ssh
->pinger
);
7745 bufchain_clear(&ssh
->queued_incoming_data
);
7752 * Reconfigure the SSH backend.
7754 static void ssh_reconfig(void *handle
, Config
*cfg
)
7756 Ssh ssh
= (Ssh
) handle
;
7757 char *rekeying
= NULL
, rekey_mandatory
= FALSE
;
7758 unsigned long old_max_data_size
;
7760 pinger_reconfig(ssh
->pinger
, &ssh
->cfg
, cfg
);
7761 ssh_setup_portfwd(ssh
, cfg
);
7763 if (ssh
->cfg
.ssh_rekey_time
!= cfg
->ssh_rekey_time
&&
7764 cfg
->ssh_rekey_time
!= 0) {
7765 long new_next
= ssh
->last_rekey
+ cfg
->ssh_rekey_time
*60*TICKSPERSEC
;
7766 long now
= GETTICKCOUNT();
7768 if (new_next
- now
< 0) {
7769 rekeying
= "timeout shortened";
7771 ssh
->next_rekey
= schedule_timer(new_next
- now
, ssh2_timer
, ssh
);
7775 old_max_data_size
= ssh
->max_data_size
;
7776 ssh
->max_data_size
= parse_blocksize(cfg
->ssh_rekey_data
);
7777 if (old_max_data_size
!= ssh
->max_data_size
&&
7778 ssh
->max_data_size
!= 0) {
7779 if (ssh
->outgoing_data_size
> ssh
->max_data_size
||
7780 ssh
->incoming_data_size
> ssh
->max_data_size
)
7781 rekeying
= "data limit lowered";
7784 if (ssh
->cfg
.compression
!= cfg
->compression
) {
7785 rekeying
= "compression setting changed";
7786 rekey_mandatory
= TRUE
;
7789 if (ssh
->cfg
.ssh2_des_cbc
!= cfg
->ssh2_des_cbc
||
7790 memcmp(ssh
->cfg
.ssh_cipherlist
, cfg
->ssh_cipherlist
,
7791 sizeof(ssh
->cfg
.ssh_cipherlist
))) {
7792 rekeying
= "cipher settings changed";
7793 rekey_mandatory
= TRUE
;
7796 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7799 if (!ssh
->kex_in_progress
) {
7800 do_ssh2_transport(ssh
, rekeying
, -1, NULL
);
7801 } else if (rekey_mandatory
) {
7802 ssh
->deferred_rekey_reason
= rekeying
;
7808 * Called to send data down the Telnet connection.
7810 static int ssh_send(void *handle
, char *buf
, int len
)
7812 Ssh ssh
= (Ssh
) handle
;
7814 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7817 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
7819 return ssh_sendbuffer(ssh
);
7823 * Called to query the current amount of buffered stdin data.
7825 static int ssh_sendbuffer(void *handle
)
7827 Ssh ssh
= (Ssh
) handle
;
7830 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7834 * If the SSH socket itself has backed up, add the total backup
7835 * size on that to any individual buffer on the stdin channel.
7838 if (ssh
->throttled_all
)
7839 override_value
= ssh
->overall_bufsize
;
7841 if (ssh
->version
== 1) {
7842 return override_value
;
7843 } else if (ssh
->version
== 2) {
7844 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
7845 return override_value
;
7847 return (override_value
+
7848 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
7855 * Called to set the size of the window from SSH's POV.
7857 static void ssh_size(void *handle
, int width
, int height
)
7859 Ssh ssh
= (Ssh
) handle
;
7860 struct Packet
*pktout
;
7862 ssh
->term_width
= width
;
7863 ssh
->term_height
= height
;
7865 switch (ssh
->state
) {
7866 case SSH_STATE_BEFORE_SIZE
:
7867 case SSH_STATE_PREPACKET
:
7868 case SSH_STATE_CLOSED
:
7869 break; /* do nothing */
7870 case SSH_STATE_INTERMED
:
7871 ssh
->size_needed
= TRUE
; /* buffer for later */
7873 case SSH_STATE_SESSION
:
7874 if (!ssh
->cfg
.nopty
) {
7875 if (ssh
->version
== 1) {
7876 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
7877 PKT_INT
, ssh
->term_height
,
7878 PKT_INT
, ssh
->term_width
,
7879 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
7880 } else if (ssh
->mainchan
) {
7881 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7882 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7883 ssh2_pkt_addstring(pktout
, "window-change");
7884 ssh2_pkt_addbool(pktout
, 0);
7885 ssh2_pkt_adduint32(pktout
, ssh
->term_width
);
7886 ssh2_pkt_adduint32(pktout
, ssh
->term_height
);
7887 ssh2_pkt_adduint32(pktout
, 0);
7888 ssh2_pkt_adduint32(pktout
, 0);
7889 ssh2_pkt_send(ssh
, pktout
);
7897 * Return a list of the special codes that make sense in this
7900 static const struct telnet_special
*ssh_get_specials(void *handle
)
7902 static const struct telnet_special ssh1_ignore_special
[] = {
7903 {"IGNORE message", TS_NOP
}
7905 static const struct telnet_special ssh2_transport_specials
[] = {
7906 {"IGNORE message", TS_NOP
},
7907 {"Repeat key exchange", TS_REKEY
},
7909 static const struct telnet_special ssh2_session_specials
[] = {
7912 /* These are the signal names defined by draft-ietf-secsh-connect-23.
7913 * They include all the ISO C signals, but are a subset of the POSIX
7914 * required signals. */
7915 {"SIGINT (Interrupt)", TS_SIGINT
},
7916 {"SIGTERM (Terminate)", TS_SIGTERM
},
7917 {"SIGKILL (Kill)", TS_SIGKILL
},
7918 {"SIGQUIT (Quit)", TS_SIGQUIT
},
7919 {"SIGHUP (Hangup)", TS_SIGHUP
},
7920 {"More signals", TS_SUBMENU
},
7921 {"SIGABRT", TS_SIGABRT
}, {"SIGALRM", TS_SIGALRM
},
7922 {"SIGFPE", TS_SIGFPE
}, {"SIGILL", TS_SIGILL
},
7923 {"SIGPIPE", TS_SIGPIPE
}, {"SIGSEGV", TS_SIGSEGV
},
7924 {"SIGUSR1", TS_SIGUSR1
}, {"SIGUSR2", TS_SIGUSR2
},
7927 static const struct telnet_special specials_end
[] = {
7930 /* XXX review this length for any changes: */
7931 static struct telnet_special ssh_specials
[lenof(ssh2_transport_specials
) +
7932 lenof(ssh2_session_specials
) +
7933 lenof(specials_end
)];
7934 Ssh ssh
= (Ssh
) handle
;
7936 #define ADD_SPECIALS(name) \
7938 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7939 memcpy(&ssh_specials[i], name, sizeof name); \
7943 if (ssh
->version
== 1) {
7944 /* Don't bother offering IGNORE if we've decided the remote
7945 * won't cope with it, since we wouldn't bother sending it if
7947 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7948 ADD_SPECIALS(ssh1_ignore_special
);
7949 } else if (ssh
->version
== 2) {
7950 ADD_SPECIALS(ssh2_transport_specials
);
7952 ADD_SPECIALS(ssh2_session_specials
);
7953 } /* else we're not ready yet */
7956 ADD_SPECIALS(specials_end
);
7957 return ssh_specials
;
7965 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7966 * can send an EOF and collect resulting output (e.g. `plink
7969 static void ssh_special(void *handle
, Telnet_Special code
)
7971 Ssh ssh
= (Ssh
) handle
;
7972 struct Packet
*pktout
;
7974 if (code
== TS_EOF
) {
7975 if (ssh
->state
!= SSH_STATE_SESSION
) {
7977 * Buffer the EOF in case we are pre-SESSION, so we can
7978 * send it as soon as we reach SESSION.
7981 ssh
->eof_needed
= TRUE
;
7984 if (ssh
->version
== 1) {
7985 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
7986 } else if (ssh
->mainchan
) {
7987 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
7988 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7989 ssh2_pkt_send(ssh
, pktout
);
7990 ssh
->send_ok
= 0; /* now stop trying to read from stdin */
7992 logevent("Sent EOF message");
7993 } else if (code
== TS_PING
|| code
== TS_NOP
) {
7994 if (ssh
->state
== SSH_STATE_CLOSED
7995 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7996 if (ssh
->version
== 1) {
7997 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7998 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
8000 pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
8001 ssh2_pkt_addstring_start(pktout
);
8002 ssh2_pkt_send_noqueue(ssh
, pktout
);
8004 } else if (code
== TS_REKEY
) {
8005 if (!ssh
->kex_in_progress
&& ssh
->version
== 2) {
8006 do_ssh2_transport(ssh
, "at user request", -1, NULL
);
8008 } else if (code
== TS_BRK
) {
8009 if (ssh
->state
== SSH_STATE_CLOSED
8010 || ssh
->state
== SSH_STATE_PREPACKET
) return;
8011 if (ssh
->version
== 1) {
8012 logevent("Unable to send BREAK signal in SSH-1");
8013 } else if (ssh
->mainchan
) {
8014 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
8015 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8016 ssh2_pkt_addstring(pktout
, "break");
8017 ssh2_pkt_addbool(pktout
, 0);
8018 ssh2_pkt_adduint32(pktout
, 0); /* default break length */
8019 ssh2_pkt_send(ssh
, pktout
);
8022 /* Is is a POSIX signal? */
8023 char *signame
= NULL
;
8024 if (code
== TS_SIGABRT
) signame
= "ABRT";
8025 if (code
== TS_SIGALRM
) signame
= "ALRM";
8026 if (code
== TS_SIGFPE
) signame
= "FPE";
8027 if (code
== TS_SIGHUP
) signame
= "HUP";
8028 if (code
== TS_SIGILL
) signame
= "ILL";
8029 if (code
== TS_SIGINT
) signame
= "INT";
8030 if (code
== TS_SIGKILL
) signame
= "KILL";
8031 if (code
== TS_SIGPIPE
) signame
= "PIPE";
8032 if (code
== TS_SIGQUIT
) signame
= "QUIT";
8033 if (code
== TS_SIGSEGV
) signame
= "SEGV";
8034 if (code
== TS_SIGTERM
) signame
= "TERM";
8035 if (code
== TS_SIGUSR1
) signame
= "USR1";
8036 if (code
== TS_SIGUSR2
) signame
= "USR2";
8037 /* The SSH-2 protocol does in principle support arbitrary named
8038 * signals, including signame@domain, but we don't support those. */
8040 /* It's a signal. */
8041 if (ssh
->version
== 2 && ssh
->mainchan
) {
8042 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
8043 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8044 ssh2_pkt_addstring(pktout
, "signal");
8045 ssh2_pkt_addbool(pktout
, 0);
8046 ssh2_pkt_addstring(pktout
, signame
);
8047 ssh2_pkt_send(ssh
, pktout
);
8048 logeventf(ssh
, "Sent signal SIG%s", signame
);
8051 /* Never heard of it. Do nothing */
8056 void *new_sock_channel(void *handle
, Socket s
)
8058 Ssh ssh
= (Ssh
) handle
;
8059 struct ssh_channel
*c
;
8060 c
= snew(struct ssh_channel
);
8065 c
->localid
= alloc_channel_id(ssh
);
8067 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
8069 bufchain_init(&c
->v
.v2
.outbuffer
);
8070 add234(ssh
->channels
, c
);
8076 * This is called when stdout/stderr (the entity to which
8077 * from_backend sends data) manages to clear some backlog.
8079 static void ssh_unthrottle(void *handle
, int bufsize
)
8081 Ssh ssh
= (Ssh
) handle
;
8082 if (ssh
->version
== 1) {
8083 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
8084 ssh
->v1_stdout_throttling
= 0;
8085 ssh1_throttle(ssh
, -1);
8088 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
8089 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
8093 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
8095 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
8097 struct Packet
*pktout
;
8099 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
8101 if (ssh
->version
== 1) {
8102 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
8103 PKT_INT
, c
->localid
,
8106 /* PKT_STR, <org:orgport>, */
8109 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
8110 ssh2_pkt_addstring(pktout
, "direct-tcpip");
8111 ssh2_pkt_adduint32(pktout
, c
->localid
);
8112 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
8113 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);/* our window size */
8114 ssh2_pkt_adduint32(pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
8115 ssh2_pkt_addstring(pktout
, hostname
);
8116 ssh2_pkt_adduint32(pktout
, port
);
8118 * We make up values for the originator data; partly it's
8119 * too much hassle to keep track, and partly I'm not
8120 * convinced the server should be told details like that
8121 * about my local network configuration.
8123 ssh2_pkt_addstring(pktout
, "client-side-connection");
8124 ssh2_pkt_adduint32(pktout
, 0);
8125 ssh2_pkt_send(ssh
, pktout
);
8129 static Socket
ssh_socket(void *handle
)
8131 Ssh ssh
= (Ssh
) handle
;
8135 static int ssh_sendok(void *handle
)
8137 Ssh ssh
= (Ssh
) handle
;
8138 return ssh
->send_ok
;
8141 static int ssh_ldisc(void *handle
, int option
)
8143 Ssh ssh
= (Ssh
) handle
;
8144 if (option
== LD_ECHO
)
8145 return ssh
->echoing
;
8146 if (option
== LD_EDIT
)
8147 return ssh
->editing
;
8151 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
8153 Ssh ssh
= (Ssh
) handle
;
8157 static void ssh_provide_logctx(void *handle
, void *logctx
)
8159 Ssh ssh
= (Ssh
) handle
;
8160 ssh
->logctx
= logctx
;
8163 static int ssh_return_exitcode(void *handle
)
8165 Ssh ssh
= (Ssh
) handle
;
8169 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
8173 * cfg_info for SSH is the currently running version of the
8174 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
8176 static int ssh_cfg_info(void *handle
)
8178 Ssh ssh
= (Ssh
) handle
;
8179 return ssh
->version
;
8183 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
8184 * that fails. This variable is the means by which scp.c can reach
8185 * into the SSH code and find out which one it got.
8187 extern int ssh_fallback_cmd(void *handle
)
8189 Ssh ssh
= (Ssh
) handle
;
8190 return ssh
->fallback_cmd
;
8193 Backend ssh_backend
= {
8203 ssh_return_exitcode
,