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 #define GET_32BIT(cp) \
260 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
261 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
262 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
263 ((unsigned long)(unsigned char)(cp)[3]))
265 #define PUT_32BIT(cp, value) { \
266 (cp)[0] = (unsigned char)((value) >> 24); \
267 (cp)[1] = (unsigned char)((value) >> 16); \
268 (cp)[2] = (unsigned char)((value) >> 8); \
269 (cp)[3] = (unsigned char)(value); }
271 /* Enumeration values for fields in SSH-1 packets */
273 PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
,
274 /* These values are for communicating relevant semantics of
275 * fields to the packet logging code. */
276 PKTT_OTHER
, PKTT_PASSWORD
, PKTT_DATA
280 * Coroutine mechanics for the sillier bits of the code. If these
281 * macros look impenetrable to you, you might find it helpful to
284 * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
286 * which explains the theory behind these macros.
288 * In particular, if you are getting `case expression not constant'
289 * errors when building with MS Visual Studio, this is because MS's
290 * Edit and Continue debugging feature causes their compiler to
291 * violate ANSI C. To disable Edit and Continue debugging:
293 * - right-click ssh.c in the FileView
295 * - select the C/C++ tab and the General category
296 * - under `Debug info:', select anything _other_ than `Program
297 * Database for Edit and Continue'.
299 #define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
302 if (!ssh->t) ssh->t = snew(struct t); \
304 #define crFinish(z) } *crLine = 0; return (z); }
305 #define crFinishV } *crLine = 0; return; }
306 #define crReturn(z) \
308 *crLine =__LINE__; return (z); case __LINE__:;\
312 *crLine=__LINE__; return; case __LINE__:;\
314 #define crStop(z) do{ *crLine = 0; return (z); }while(0)
315 #define crStopV do{ *crLine = 0; return; }while(0)
316 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
317 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
319 typedef struct ssh_tag
*Ssh
;
322 static struct Packet
*ssh2_pkt_init(int pkt_type
);
323 static void ssh2_pkt_addbool(struct Packet
*, unsigned char value
);
324 static void ssh2_pkt_adduint32(struct Packet
*, unsigned long value
);
325 static void ssh2_pkt_addstring_start(struct Packet
*);
326 static void ssh2_pkt_addstring_str(struct Packet
*, char *data
);
327 static void ssh2_pkt_addstring_data(struct Packet
*, char *data
, int len
);
328 static void ssh2_pkt_addstring(struct Packet
*, char *data
);
329 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
);
330 static void ssh2_pkt_addmp(struct Packet
*, Bignum b
);
331 static int ssh2_pkt_construct(Ssh
, struct Packet
*);
332 static void ssh2_pkt_send(Ssh
, struct Packet
*);
333 static void ssh2_pkt_send_noqueue(Ssh
, struct Packet
*);
334 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
335 struct Packet
*pktin
);
336 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
337 struct Packet
*pktin
);
340 * Buffer management constants. There are several of these for
341 * various different purposes:
343 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
344 * on a local data stream before we throttle the whole SSH
345 * connection (in SSH1 only). Throttling the whole connection is
346 * pretty drastic so we set this high in the hope it won't
349 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
350 * on the SSH connection itself before we defensively throttle
351 * _all_ local data streams. This is pretty drastic too (though
352 * thankfully unlikely in SSH2 since the window mechanism should
353 * ensure that the server never has any need to throttle its end
354 * of the connection), so we set this high as well.
356 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
360 #define SSH1_BUFFER_LIMIT 32768
361 #define SSH_MAX_BACKLOG 32768
362 #define OUR_V2_WINSIZE 16384
363 #define OUR_V2_MAXPKT 0x4000UL
365 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
367 static void *nullmac_make_context(void)
371 static void nullmac_free_context(void *handle
)
374 static void nullmac_key(void *handle
, unsigned char *key
)
377 static void nullmac_generate(void *handle
, unsigned char *blk
, int len
,
381 static int nullmac_verify(void *handle
, unsigned char *blk
, int len
,
386 const static struct ssh_mac ssh_mac_none
= {
387 nullmac_make_context
, nullmac_free_context
, nullmac_key
,
388 nullmac_generate
, nullmac_verify
, "none", 0
390 const static struct ssh_mac
*macs
[] = {
391 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
393 const static struct ssh_mac
*buggymacs
[] = {
394 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
397 static void *ssh_comp_none_init(void)
401 static void ssh_comp_none_cleanup(void *handle
)
404 static int ssh_comp_none_block(void *handle
, unsigned char *block
, int len
,
405 unsigned char **outblock
, int *outlen
)
409 static int ssh_comp_none_disable(void *handle
)
413 const static struct ssh_compress ssh_comp_none
= {
415 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
416 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
417 ssh_comp_none_disable
, NULL
419 extern const struct ssh_compress ssh_zlib
;
420 const static struct ssh_compress
*compressions
[] = {
421 &ssh_zlib
, &ssh_comp_none
424 enum { /* channel types */
429 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
433 * 2-3-4 tree storing channels.
436 Ssh ssh
; /* pointer back to main context */
437 unsigned remoteid
, localid
;
440 * In SSH1, this value contains four bits:
442 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
443 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
444 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
445 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
447 * A channel is completely finished with when all four bits are set.
451 struct ssh1_data_channel
{
454 struct ssh2_data_channel
{
456 unsigned remwindow
, remmaxpkt
;
461 struct ssh_agent_channel
{
462 unsigned char *message
;
463 unsigned char msglen
[4];
464 unsigned lensofar
, totallen
;
466 struct ssh_x11_channel
{
469 struct ssh_pfd_channel
{
476 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
477 * 2 use this structure in different ways, reflecting SSH 2's
478 * altogether saner approach to port forwarding.
480 * In SSH 1, you arrange a remote forwarding by sending the server
481 * the remote port number, and the local destination host:port.
482 * When a connection comes in, the server sends you back that
483 * host:port pair, and you connect to it. This is a ready-made
484 * security hole if you're not on the ball: a malicious server
485 * could send you back _any_ host:port pair, so if you trustingly
486 * connect to the address it gives you then you've just opened the
487 * entire inside of your corporate network just by connecting
488 * through it to a dodgy SSH server. Hence, we must store a list of
489 * host:port pairs we _are_ trying to forward to, and reject a
490 * connection request from the server if it's not in the list.
492 * In SSH 2, each side of the connection minds its own business and
493 * doesn't send unnecessary information to the other. You arrange a
494 * remote forwarding by sending the server just the remote port
495 * number. When a connection comes in, the server tells you which
496 * of its ports was connected to; and _you_ have to remember what
497 * local host:port pair went with that port number.
499 * Hence, in SSH 1 this structure is indexed by destination
500 * host:port pair, whereas in SSH 2 it is indexed by source port.
502 struct ssh_portfwd
; /* forward declaration */
504 struct ssh_rportfwd
{
505 unsigned sport
, dport
;
508 struct ssh_portfwd
*pfrec
;
510 #define free_rportfwd(pf) ( \
511 ((pf) ? (sfree((pf)->sportdesc)) : (void)0 ), sfree(pf) )
514 * Separately to the rportfwd tree (which is for looking up port
515 * open requests from the server), a tree of _these_ structures is
516 * used to keep track of all the currently open port forwardings,
517 * so that we can reconfigure in mid-session if the user requests
521 enum { DESTROY
, KEEP
, CREATE
} status
;
523 unsigned sport
, dport
;
526 struct ssh_rportfwd
*remote
;
530 #define free_portfwd(pf) ( \
531 ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr), \
532 sfree((pf)->sserv), sfree((pf)->dserv)) : (void)0 ), sfree(pf) )
536 long forcepad
; /* Force padding to at least this length */
538 unsigned long sequence
;
543 long encrypted_len
; /* for SSH2 total-size counting */
546 * State associated with packet logging
550 struct logblank_t
*blanks
;
553 static void ssh1_protocol(Ssh ssh
, void *vin
, int inlen
,
554 struct Packet
*pktin
);
555 static void ssh2_protocol(Ssh ssh
, void *vin
, int inlen
,
556 struct Packet
*pktin
);
557 static void ssh1_protocol_setup(Ssh ssh
);
558 static void ssh2_protocol_setup(Ssh ssh
);
559 static void ssh_size(void *handle
, int width
, int height
);
560 static void ssh_special(void *handle
, Telnet_Special
);
561 static int ssh2_try_send(struct ssh_channel
*c
);
562 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
563 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
564 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
565 static int ssh_sendbuffer(void *handle
);
566 static int ssh_do_close(Ssh ssh
, int notify_exit
);
567 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
);
568 static int ssh2_pkt_getbool(struct Packet
*pkt
);
569 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
);
570 static void ssh2_timer(void *ctx
, long now
);
571 static int do_ssh2_transport(Ssh ssh
, void *vin
, int inlen
,
572 struct Packet
*pktin
);
574 struct rdpkt1_state_tag
{
575 long len
, pad
, biglen
, to_read
;
576 unsigned long realcrc
, gotcrc
;
580 struct Packet
*pktin
;
583 struct rdpkt2_state_tag
{
584 long len
, pad
, payload
, packetlen
, maclen
;
587 unsigned long incoming_sequence
;
588 struct Packet
*pktin
;
591 typedef void (*handler_fn_t
)(Ssh ssh
, struct Packet
*pktin
);
592 typedef void (*chandler_fn_t
)(Ssh ssh
, struct Packet
*pktin
, void *ctx
);
594 struct queued_handler
;
595 struct queued_handler
{
597 chandler_fn_t handler
;
599 struct queued_handler
*next
;
603 const struct plug_function_table
*fn
;
604 /* the above field _must_ be first in the structure */
606 SHA_State exhash
, exhashbase
;
613 unsigned char session_key
[32];
615 int v1_remote_protoflags
;
616 int v1_local_protoflags
;
617 int agentfwd_enabled
;
620 const struct ssh_cipher
*cipher
;
623 const struct ssh2_cipher
*cscipher
, *sccipher
;
624 void *cs_cipher_ctx
, *sc_cipher_ctx
;
625 const struct ssh_mac
*csmac
, *scmac
;
626 void *cs_mac_ctx
, *sc_mac_ctx
;
627 const struct ssh_compress
*cscomp
, *sccomp
;
628 void *cs_comp_ctx
, *sc_comp_ctx
;
629 const struct ssh_kex
*kex
;
630 const struct ssh_signkey
*hostkey
;
631 unsigned char v2_session_id
[20];
637 int echoing
, editing
;
641 int ospeed
, ispeed
; /* temporaries */
642 int term_width
, term_height
;
644 tree234
*channels
; /* indexed by local id */
645 struct ssh_channel
*mainchan
; /* primary session channel */
649 tree234
*rportfwds
, *portfwds
;
653 SSH_STATE_BEFORE_SIZE
,
659 int size_needed
, eof_needed
;
661 struct Packet
**queue
;
662 int queuelen
, queuesize
;
664 unsigned char *deferred_send_data
;
665 int deferred_len
, deferred_size
;
668 * Gross hack: pscp will try to start SFTP but fall back to
669 * scp1 if that fails. This variable is the means by which
670 * scp.c can reach into the SSH code and find out which one it
676 * Used for username and password input.
678 char *userpass_input_buffer
;
679 int userpass_input_buflen
;
680 int userpass_input_bufpos
;
681 int userpass_input_echo
;
688 int v1_throttle_count
;
691 int v1_stdout_throttling
;
692 int v2_outgoing_sequence
;
694 int ssh1_rdpkt_crstate
;
695 int ssh2_rdpkt_crstate
;
696 int do_ssh_init_crstate
;
697 int ssh_gotdata_crstate
;
698 int do_ssh1_login_crstate
;
699 int do_ssh1_connection_crstate
;
700 int do_ssh2_transport_crstate
;
701 int do_ssh2_authconn_crstate
;
703 void *do_ssh_init_state
;
704 void *do_ssh1_login_state
;
705 void *do_ssh2_transport_state
;
706 void *do_ssh2_authconn_state
;
708 struct rdpkt1_state_tag rdpkt1_state
;
709 struct rdpkt2_state_tag rdpkt2_state
;
711 /* ssh1 and ssh2 use this for different things, but both use it */
712 int protocol_initial_phase_done
;
714 void (*protocol
) (Ssh ssh
, void *vin
, int inlen
,
716 struct Packet
*(*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
719 * We maintain a full _copy_ of a Config structure here, not
720 * merely a pointer to it. That way, when we're passed a new
721 * one for reconfiguration, we can check the differences and
722 * potentially reconfigure port forwardings etc in mid-session.
727 * Used to transfer data back from async agent callbacks.
729 void *agent_response
;
730 int agent_response_len
;
733 * Dispatch table for packet types that we may have to deal
736 handler_fn_t packet_dispatch
[256];
739 * Queues of one-off handler functions for success/failure
740 * indications from a request.
742 struct queued_handler
*qhead
, *qtail
;
745 * This module deals with sending keepalives.
750 * Track incoming and outgoing data sizes and time, for
753 unsigned long incoming_data_size
, outgoing_data_size
, deferred_data_size
;
754 unsigned long max_data_size
;
756 long next_rekey
, last_rekey
;
757 char *deferred_rekey_reason
; /* points to STATIC string; don't free */
760 #define logevent(s) logevent(ssh->frontend, s)
762 /* logevent, only printf-formatted. */
763 static void logeventf(Ssh ssh
, const char *fmt
, ...)
769 buf
= dupvprintf(fmt
, ap
);
775 #define bombout(msg) \
777 char *text = dupprintf msg; \
778 ssh_do_close(ssh, FALSE); \
780 connection_fatal(ssh->frontend, "%s", text); \
784 /* Functions to leave bits out of the SSH packet log file. */
786 static void dont_log_password(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
788 if (ssh
->cfg
.logomitpass
)
789 pkt
->logmode
= blanktype
;
792 static void dont_log_data(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
794 if (ssh
->cfg
.logomitdata
)
795 pkt
->logmode
= blanktype
;
798 static void end_log_omission(Ssh ssh
, struct Packet
*pkt
)
800 pkt
->logmode
= PKTLOG_EMIT
;
803 static int ssh_channelcmp(void *av
, void *bv
)
805 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
806 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
807 if (a
->localid
< b
->localid
)
809 if (a
->localid
> b
->localid
)
813 static int ssh_channelfind(void *av
, void *bv
)
815 unsigned *a
= (unsigned *) av
;
816 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
824 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
826 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
827 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
829 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
830 return i
< 0 ?
-1 : +1;
831 if (a
->dport
> b
->dport
)
833 if (a
->dport
< b
->dport
)
838 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
840 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
841 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
843 if (a
->sport
> b
->sport
)
845 if (a
->sport
< b
->sport
)
851 * Special form of strcmp which can cope with NULL inputs. NULL is
852 * defined to sort before even the empty string.
854 static int nullstrcmp(const char *a
, const char *b
)
856 if (a
== NULL
&& b
== NULL
)
865 static int ssh_portcmp(void *av
, void *bv
)
867 struct ssh_portfwd
*a
= (struct ssh_portfwd
*) av
;
868 struct ssh_portfwd
*b
= (struct ssh_portfwd
*) bv
;
870 if (a
->type
> b
->type
)
872 if (a
->type
< b
->type
)
874 if (a
->addressfamily
> b
->addressfamily
)
876 if (a
->addressfamily
< b
->addressfamily
)
878 if ( (i
= nullstrcmp(a
->saddr
, b
->saddr
)) != 0)
879 return i
< 0 ?
-1 : +1;
880 if (a
->sport
> b
->sport
)
882 if (a
->sport
< b
->sport
)
884 if (a
->type
!= 'D') {
885 if ( (i
= nullstrcmp(a
->daddr
, b
->daddr
)) != 0)
886 return i
< 0 ?
-1 : +1;
887 if (a
->dport
> b
->dport
)
889 if (a
->dport
< b
->dport
)
895 static int alloc_channel_id(Ssh ssh
)
897 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
898 unsigned low
, high
, mid
;
900 struct ssh_channel
*c
;
903 * First-fit allocation of channel numbers: always pick the
904 * lowest unused one. To do this, binary-search using the
905 * counted B-tree to find the largest channel ID which is in a
906 * contiguous sequence from the beginning. (Precisely
907 * everything in that sequence must have ID equal to its tree
908 * index plus CHANNEL_NUMBER_OFFSET.)
910 tsize
= count234(ssh
->channels
);
914 while (high
- low
> 1) {
915 mid
= (high
+ low
) / 2;
916 c
= index234(ssh
->channels
, mid
);
917 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
918 low
= mid
; /* this one is fine */
920 high
= mid
; /* this one is past it */
923 * Now low points to either -1, or the tree index of the
924 * largest ID in the initial sequence.
927 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
928 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
930 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
933 static void c_write(Ssh ssh
, const char *buf
, int len
)
935 if ((flags
& FLAG_STDERR
)) {
937 for (i
= 0; i
< len
; i
++)
939 fputc(buf
[i
], stderr
);
942 from_backend(ssh
->frontend
, 1, buf
, len
);
945 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
948 for (i
= 0; i
< len
; i
++) {
950 c_write(ssh
, "\r\n", 2);
951 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
952 c_write(ssh
, buf
+ i
, 1);
956 static void c_write_str(Ssh ssh
, const char *buf
)
958 c_write(ssh
, buf
, strlen(buf
));
961 static void ssh_free_packet(struct Packet
*pkt
)
966 static struct Packet
*ssh_new_packet(void)
968 struct Packet
*pkt
= snew(struct Packet
);
972 pkt
->logmode
= PKTLOG_EMIT
;
980 * Collect incoming data in the incoming packet buffer.
981 * Decipher and verify the packet when it is completely read.
982 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
983 * Update the *data and *datalen variables.
984 * Return a Packet structure when a packet is completed.
986 static struct Packet
*ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
988 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
990 crBegin(ssh
->ssh1_rdpkt_crstate
);
992 st
->pktin
= ssh_new_packet();
995 st
->pktin
->length
= 0;
997 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
998 while ((*datalen
) == 0)
1000 st
->len
= (st
->len
<< 8) + **data
;
1001 (*data
)++, (*datalen
)--;
1004 st
->pad
= 8 - (st
->len
% 8);
1005 st
->biglen
= st
->len
+ st
->pad
;
1006 st
->pktin
->length
= st
->len
- 5;
1008 if (st
->biglen
< 0) {
1009 bombout(("Extremely large packet length from server suggests"
1010 " data stream corruption"));
1011 ssh_free_packet(st
->pktin
);
1015 st
->pktin
->maxlen
= st
->biglen
;
1016 st
->pktin
->data
= snewn(st
->biglen
+ APIEXTRA
, unsigned char);
1018 st
->to_read
= st
->biglen
;
1019 st
->p
= st
->pktin
->data
;
1020 while (st
->to_read
> 0) {
1021 st
->chunk
= st
->to_read
;
1022 while ((*datalen
) == 0)
1024 if (st
->chunk
> (*datalen
))
1025 st
->chunk
= (*datalen
);
1026 memcpy(st
->p
, *data
, st
->chunk
);
1028 *datalen
-= st
->chunk
;
1030 st
->to_read
-= st
->chunk
;
1033 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, st
->pktin
->data
,
1034 st
->biglen
, NULL
)) {
1035 bombout(("Network attack (CRC compensation) detected!"));
1036 ssh_free_packet(st
->pktin
);
1041 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, st
->pktin
->data
, st
->biglen
);
1043 st
->realcrc
= crc32_compute(st
->pktin
->data
, st
->biglen
- 4);
1044 st
->gotcrc
= GET_32BIT(st
->pktin
->data
+ st
->biglen
- 4);
1045 if (st
->gotcrc
!= st
->realcrc
) {
1046 bombout(("Incorrect CRC received on packet"));
1047 ssh_free_packet(st
->pktin
);
1051 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1052 st
->pktin
->savedpos
= 0;
1054 if (ssh
->v1_compressing
) {
1055 unsigned char *decompblk
;
1057 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
1058 st
->pktin
->body
- 1, st
->pktin
->length
+ 1,
1059 &decompblk
, &decomplen
)) {
1060 bombout(("Zlib decompression encountered invalid data"));
1061 ssh_free_packet(st
->pktin
);
1065 if (st
->pktin
->maxlen
< st
->pad
+ decomplen
) {
1066 st
->pktin
->maxlen
= st
->pad
+ decomplen
;
1067 st
->pktin
->data
= sresize(st
->pktin
->data
,
1068 st
->pktin
->maxlen
+ APIEXTRA
,
1070 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1073 memcpy(st
->pktin
->body
- 1, decompblk
, decomplen
);
1075 st
->pktin
->length
= decomplen
- 1;
1078 st
->pktin
->type
= st
->pktin
->body
[-1];
1081 * Log incoming packet, possibly omitting sensitive fields.
1085 struct logblank_t blank
;
1086 if (ssh
->cfg
.logomitdata
) {
1087 int do_blank
= FALSE
, blank_prefix
= 0;
1088 /* "Session data" packets - omit the data field */
1089 if ((st
->pktin
->type
== SSH1_SMSG_STDOUT_DATA
) ||
1090 (st
->pktin
->type
== SSH1_SMSG_STDERR_DATA
)) {
1091 do_blank
= TRUE
; blank_prefix
= 0;
1092 } else if (st
->pktin
->type
== SSH1_MSG_CHANNEL_DATA
) {
1093 do_blank
= TRUE
; blank_prefix
= 4;
1096 blank
.offset
= blank_prefix
;
1097 blank
.len
= st
->pktin
->length
;
1098 blank
.type
= PKTLOG_OMIT
;
1102 log_packet(ssh
->logctx
,
1103 PKT_INCOMING
, st
->pktin
->type
,
1104 ssh1_pkt_type(st
->pktin
->type
),
1105 st
->pktin
->body
, st
->pktin
->length
,
1109 crFinish(st
->pktin
);
1112 static struct Packet
*ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1114 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1116 crBegin(ssh
->ssh2_rdpkt_crstate
);
1118 st
->pktin
= ssh_new_packet();
1120 st
->pktin
->type
= 0;
1121 st
->pktin
->length
= 0;
1123 st
->cipherblk
= ssh
->sccipher
->blksize
;
1126 if (st
->cipherblk
< 8)
1129 st
->pktin
->data
= snewn(st
->cipherblk
+ APIEXTRA
, unsigned char);
1132 * Acquire and decrypt the first block of the packet. This will
1133 * contain the length and padding details.
1135 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1136 while ((*datalen
) == 0)
1138 st
->pktin
->data
[st
->i
] = *(*data
)++;
1143 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1144 st
->pktin
->data
, st
->cipherblk
);
1147 * Now get the length and padding figures.
1149 st
->len
= GET_32BIT(st
->pktin
->data
);
1150 st
->pad
= st
->pktin
->data
[4];
1153 * _Completely_ silly lengths should be stomped on before they
1154 * do us any more damage.
1156 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
1157 bombout(("Incoming packet was garbled on decryption"));
1158 ssh_free_packet(st
->pktin
);
1163 * This enables us to deduce the payload length.
1165 st
->payload
= st
->len
- st
->pad
- 1;
1167 st
->pktin
->length
= st
->payload
+ 5;
1170 * So now we can work out the total packet length.
1172 st
->packetlen
= st
->len
+ 4;
1173 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1176 * Allocate memory for the rest of the packet.
1178 st
->pktin
->maxlen
= st
->packetlen
+ st
->maclen
;
1179 st
->pktin
->data
= sresize(st
->pktin
->data
,
1180 st
->pktin
->maxlen
+ APIEXTRA
,
1184 * Read and decrypt the remainder of the packet.
1186 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1188 while ((*datalen
) == 0)
1190 st
->pktin
->data
[st
->i
] = *(*data
)++;
1193 /* Decrypt everything _except_ the MAC. */
1195 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1196 st
->pktin
->data
+ st
->cipherblk
,
1197 st
->packetlen
- st
->cipherblk
);
1199 st
->pktin
->encrypted_len
= st
->packetlen
;
1205 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, st
->pktin
->data
, st
->len
+ 4,
1206 st
->incoming_sequence
)) {
1207 bombout(("Incorrect MAC received on packet"));
1208 ssh_free_packet(st
->pktin
);
1212 st
->pktin
->sequence
= st
->incoming_sequence
++;
1215 * Decompress packet payload.
1218 unsigned char *newpayload
;
1221 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1222 st
->pktin
->data
+ 5, st
->pktin
->length
- 5,
1223 &newpayload
, &newlen
)) {
1224 if (st
->pktin
->maxlen
< newlen
+ 5) {
1225 st
->pktin
->maxlen
= newlen
+ 5;
1226 st
->pktin
->data
= sresize(st
->pktin
->data
,
1227 st
->pktin
->maxlen
+ APIEXTRA
,
1230 st
->pktin
->length
= 5 + newlen
;
1231 memcpy(st
->pktin
->data
+ 5, newpayload
, newlen
);
1236 st
->pktin
->savedpos
= 6;
1237 st
->pktin
->body
= st
->pktin
->data
;
1238 st
->pktin
->type
= st
->pktin
->data
[5];
1241 * Log incoming packet, possibly omitting sensitive fields.
1245 struct logblank_t blank
;
1246 if (ssh
->cfg
.logomitdata
) {
1247 int do_blank
= FALSE
, blank_prefix
= 0;
1248 /* "Session data" packets - omit the data field */
1249 if (st
->pktin
->type
== SSH2_MSG_CHANNEL_DATA
) {
1250 do_blank
= TRUE
; blank_prefix
= 4;
1251 } else if (st
->pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1252 do_blank
= TRUE
; blank_prefix
= 8;
1255 blank
.offset
= blank_prefix
;
1256 blank
.len
= (st
->pktin
->length
-6) - blank_prefix
;
1257 blank
.type
= PKTLOG_OMIT
;
1261 log_packet(ssh
->logctx
, PKT_INCOMING
, st
->pktin
->type
,
1262 ssh2_pkt_type(ssh
->pkt_ctx
, st
->pktin
->type
),
1263 st
->pktin
->data
+6, st
->pktin
->length
-6,
1267 crFinish(st
->pktin
);
1270 static void ssh1_pktout_size(struct Packet
*pkt
, int len
)
1274 len
+= 5; /* type and CRC */
1275 pad
= 8 - (len
% 8);
1278 pkt
->length
= len
- 5;
1279 if (pkt
->maxlen
< biglen
) {
1280 pkt
->maxlen
= biglen
;
1281 pkt
->data
= sresize(pkt
->data
, biglen
+ 4 + APIEXTRA
, unsigned char);
1283 pkt
->body
= pkt
->data
+ 4 + pad
+ 1;
1286 static struct Packet
*s_wrpkt_start(int type
, int len
)
1288 struct Packet
*pkt
= ssh_new_packet();
1289 ssh1_pktout_size(pkt
, len
);
1291 /* Initialise log omission state */
1297 static int s_wrpkt_prepare(Ssh ssh
, struct Packet
*pkt
)
1303 * XXX various versions of SC (including 8.8.4) screw up the
1304 * register allocation in this function and use the same register
1305 * (D6) for len and as a temporary, with predictable results. The
1306 * following sledgehammer prevents this.
1312 pkt
->body
[-1] = pkt
->type
;
1315 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->type
,
1316 ssh1_pkt_type(pkt
->type
),
1317 pkt
->body
, pkt
->length
,
1318 pkt
->nblanks
, pkt
->blanks
);
1319 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1322 if (ssh
->v1_compressing
) {
1323 unsigned char *compblk
;
1325 zlib_compress_block(ssh
->cs_comp_ctx
,
1326 pkt
->body
- 1, pkt
->length
+ 1,
1327 &compblk
, &complen
);
1328 ssh1_pktout_size(pkt
, complen
- 1);
1329 memcpy(pkt
->body
- 1, compblk
, complen
);
1333 len
= pkt
->length
+ 5; /* type and CRC */
1334 pad
= 8 - (len
% 8);
1337 for (i
= 0; i
< pad
; i
++)
1338 pkt
->data
[i
+ 4] = random_byte();
1339 crc
= crc32_compute(pkt
->data
+ 4, biglen
- 4);
1340 PUT_32BIT(pkt
->data
+ biglen
, crc
);
1341 PUT_32BIT(pkt
->data
, len
);
1344 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, pkt
->data
+ 4, biglen
);
1349 static void s_wrpkt(Ssh ssh
, struct Packet
*pkt
)
1352 len
= s_wrpkt_prepare(ssh
, pkt
);
1353 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1354 if (backlog
> SSH_MAX_BACKLOG
)
1355 ssh_throttle_all(ssh
, 1, backlog
);
1358 static void s_wrpkt_defer(Ssh ssh
, struct Packet
*pkt
)
1361 len
= s_wrpkt_prepare(ssh
, pkt
);
1362 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1363 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1364 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1368 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1369 ssh
->deferred_len
+= len
;
1373 * Construct a packet with the specified contents.
1375 static struct Packet
*construct_packet(Ssh ssh
, int pkttype
,
1376 va_list ap1
, va_list ap2
)
1378 unsigned char *p
, *argp
, argchar
;
1379 unsigned long argint
;
1380 int pktlen
, argtype
, arglen
;
1385 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1388 (void) va_arg(ap1
, int);
1392 (void) va_arg(ap1
, int);
1396 (void) va_arg(ap1
, unsigned char *);
1397 arglen
= va_arg(ap1
, int);
1401 argp
= va_arg(ap1
, unsigned char *);
1402 arglen
= strlen((char *)argp
);
1403 pktlen
+= 4 + arglen
;
1406 bn
= va_arg(ap1
, Bignum
);
1407 pktlen
+= ssh1_bignum_length(bn
);
1412 /* ignore this pass */
1419 pkt
= s_wrpkt_start(pkttype
, pktlen
);
1422 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1423 int offset
= p
- pkt
->body
, len
= 0;
1425 /* Actual fields in the packet */
1427 argint
= va_arg(ap2
, int);
1428 PUT_32BIT(p
, argint
);
1432 argchar
= (unsigned char) va_arg(ap2
, int);
1437 argp
= va_arg(ap2
, unsigned char *);
1438 arglen
= va_arg(ap2
, int);
1439 memcpy(p
, argp
, arglen
);
1443 argp
= va_arg(ap2
, unsigned char *);
1444 arglen
= strlen((char *)argp
);
1445 PUT_32BIT(p
, arglen
);
1446 memcpy(p
+ 4, argp
, arglen
);
1450 bn
= va_arg(ap2
, Bignum
);
1451 len
= ssh1_write_bignum(p
, bn
);
1453 /* Tokens for modifications to packet logging */
1455 dont_log_password(ssh
, pkt
, PKTLOG_BLANK
);
1458 dont_log_data(ssh
, pkt
, PKTLOG_OMIT
);
1461 end_log_omission(ssh
, pkt
);
1465 /* Deal with logfile omission, if required. */
1466 if (len
&& (pkt
->logmode
!= PKTLOG_EMIT
)) {
1468 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
,
1470 pkt
->blanks
[pkt
->nblanks
-1].offset
= offset
;
1471 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1472 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1479 static void send_packet(Ssh ssh
, int pkttype
, ...)
1483 va_start(ap1
, pkttype
);
1484 va_start(ap2
, pkttype
);
1485 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1489 ssh_free_packet(pkt
);
1492 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1496 va_start(ap1
, pkttype
);
1497 va_start(ap2
, pkttype
);
1498 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1501 s_wrpkt_defer(ssh
, pkt
);
1502 ssh_free_packet(pkt
);
1505 static int ssh_versioncmp(char *a
, char *b
)
1508 unsigned long av
, bv
;
1510 av
= strtoul(a
, &ae
, 10);
1511 bv
= strtoul(b
, &be
, 10);
1513 return (av
< bv ?
-1 : +1);
1518 av
= strtoul(ae
, &ae
, 10);
1519 bv
= strtoul(be
, &be
, 10);
1521 return (av
< bv ?
-1 : +1);
1526 * Utility routines for putting an SSH-protocol `string' and
1527 * `uint32' into a SHA state.
1530 static void sha_string(SHA_State
* s
, void *str
, int len
)
1532 unsigned char lenblk
[4];
1533 PUT_32BIT(lenblk
, len
);
1534 SHA_Bytes(s
, lenblk
, 4);
1535 SHA_Bytes(s
, str
, len
);
1538 static void sha_uint32(SHA_State
* s
, unsigned i
)
1540 unsigned char intblk
[4];
1541 PUT_32BIT(intblk
, i
);
1542 SHA_Bytes(s
, intblk
, 4);
1546 * SSH2 packet construction functions.
1548 static void ssh2_pkt_ensure(struct Packet
*pkt
, int length
)
1550 if (pkt
->maxlen
< length
) {
1551 pkt
->maxlen
= length
+ 256;
1552 pkt
->data
= sresize(pkt
->data
, pkt
->maxlen
+ APIEXTRA
, unsigned char);
1555 static void ssh2_pkt_adddata(struct Packet
*pkt
, void *data
, int len
)
1557 if (pkt
->logmode
!= PKTLOG_EMIT
) {
1559 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
, struct logblank_t
);
1560 pkt
->blanks
[pkt
->nblanks
-1].offset
= pkt
->length
- 6;
1561 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1562 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1565 ssh2_pkt_ensure(pkt
, pkt
->length
);
1566 memcpy(pkt
->data
+ pkt
->length
- len
, data
, len
);
1568 static void ssh2_pkt_addbyte(struct Packet
*pkt
, unsigned char byte
)
1570 ssh2_pkt_adddata(pkt
, &byte
, 1);
1572 static struct Packet
*ssh2_pkt_init(int pkt_type
)
1574 struct Packet
*pkt
= ssh_new_packet();
1577 ssh2_pkt_addbyte(pkt
, (unsigned char) pkt_type
);
1580 static void ssh2_pkt_addbool(struct Packet
*pkt
, unsigned char value
)
1582 ssh2_pkt_adddata(pkt
, &value
, 1);
1584 static void ssh2_pkt_adduint32(struct Packet
*pkt
, unsigned long value
)
1587 PUT_32BIT(x
, value
);
1588 ssh2_pkt_adddata(pkt
, x
, 4);
1590 static void ssh2_pkt_addstring_start(struct Packet
*pkt
)
1592 ssh2_pkt_adduint32(pkt
, 0);
1593 pkt
->savedpos
= pkt
->length
;
1595 static void ssh2_pkt_addstring_str(struct Packet
*pkt
, char *data
)
1597 ssh2_pkt_adddata(pkt
, data
, strlen(data
));
1598 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1600 static void ssh2_pkt_addstring_data(struct Packet
*pkt
, char *data
, int len
)
1602 ssh2_pkt_adddata(pkt
, data
, len
);
1603 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1605 static void ssh2_pkt_addstring(struct Packet
*pkt
, char *data
)
1607 ssh2_pkt_addstring_start(pkt
);
1608 ssh2_pkt_addstring_str(pkt
, data
);
1610 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1613 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1614 p
= snewn(n
+ 1, unsigned char);
1616 fatalbox("out of memory");
1618 for (i
= 1; i
<= n
; i
++)
1619 p
[i
] = bignum_byte(b
, n
- i
);
1621 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1623 memmove(p
, p
+ i
, n
+ 1 - i
);
1627 static void ssh2_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1631 p
= ssh2_mpint_fmt(b
, &len
);
1632 ssh2_pkt_addstring_start(pkt
);
1633 ssh2_pkt_addstring_data(pkt
, (char *)p
, len
);
1638 * Construct an SSH2 final-form packet: compress it, encrypt it,
1639 * put the MAC on it. Final packet, ready to be sent, is stored in
1640 * pkt->data. Total length is returned.
1642 static int ssh2_pkt_construct(Ssh ssh
, struct Packet
*pkt
)
1644 int cipherblk
, maclen
, padding
, i
;
1647 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[5],
1648 ssh2_pkt_type(ssh
->pkt_ctx
, pkt
->data
[5]),
1649 pkt
->data
+ 6, pkt
->length
- 6,
1650 pkt
->nblanks
, pkt
->blanks
);
1651 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1655 * Compress packet payload.
1658 unsigned char *newpayload
;
1661 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, pkt
->data
+ 5,
1663 &newpayload
, &newlen
)) {
1665 ssh2_pkt_adddata(pkt
, newpayload
, newlen
);
1671 * Add padding. At least four bytes, and must also bring total
1672 * length (minus MAC) up to a multiple of the block size.
1673 * If pkt->forcepad is set, make sure the packet is at least that size
1676 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1677 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1679 if (pkt
->length
+ padding
< pkt
->forcepad
)
1680 padding
= pkt
->forcepad
- pkt
->length
;
1682 (cipherblk
- (pkt
->length
+ padding
) % cipherblk
) % cipherblk
;
1683 assert(padding
<= 255);
1684 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1685 ssh2_pkt_ensure(pkt
, pkt
->length
+ padding
+ maclen
);
1686 pkt
->data
[4] = padding
;
1687 for (i
= 0; i
< padding
; i
++)
1688 pkt
->data
[pkt
->length
+ i
] = random_byte();
1689 PUT_32BIT(pkt
->data
, pkt
->length
+ padding
- 4);
1691 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, pkt
->data
,
1692 pkt
->length
+ padding
,
1693 ssh
->v2_outgoing_sequence
);
1694 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1697 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1698 pkt
->data
, pkt
->length
+ padding
);
1700 pkt
->encrypted_len
= pkt
->length
+ padding
;
1702 /* Ready-to-send packet starts at pkt->data. We return length. */
1703 return pkt
->length
+ padding
+ maclen
;
1707 * Routines called from the main SSH code to send packets. There
1708 * are quite a few of these, because we have two separate
1709 * mechanisms for delaying the sending of packets:
1711 * - In order to send an IGNORE message and a password message in
1712 * a single fixed-length blob, we require the ability to
1713 * concatenate the encrypted forms of those two packets _into_ a
1714 * single blob and then pass it to our <network.h> transport
1715 * layer in one go. Hence, there's a deferment mechanism which
1716 * works after packet encryption.
1718 * - In order to avoid sending any connection-layer messages
1719 * during repeat key exchange, we have to queue up any such
1720 * outgoing messages _before_ they are encrypted (and in
1721 * particular before they're allocated sequence numbers), and
1722 * then send them once we've finished.
1724 * I call these mechanisms `defer' and `queue' respectively, so as
1725 * to distinguish them reasonably easily.
1727 * The functions send_noqueue() and defer_noqueue() free the packet
1728 * structure they are passed. Every outgoing packet goes through
1729 * precisely one of these functions in its life; packets passed to
1730 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1731 * these or get queued, and then when the queue is later emptied
1732 * the packets are all passed to defer_noqueue().
1736 * Send an SSH2 packet immediately, without queuing or deferring.
1738 static void ssh2_pkt_send_noqueue(Ssh ssh
, struct Packet
*pkt
)
1742 len
= ssh2_pkt_construct(ssh
, pkt
);
1743 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1744 if (backlog
> SSH_MAX_BACKLOG
)
1745 ssh_throttle_all(ssh
, 1, backlog
);
1747 ssh
->outgoing_data_size
+= pkt
->encrypted_len
;
1748 if (!ssh
->kex_in_progress
&&
1749 ssh
->max_data_size
!= 0 &&
1750 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1751 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1753 ssh_free_packet(pkt
);
1757 * Defer an SSH2 packet.
1759 static void ssh2_pkt_defer_noqueue(Ssh ssh
, struct Packet
*pkt
)
1761 int len
= ssh2_pkt_construct(ssh
, pkt
);
1762 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1763 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1764 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1768 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1769 ssh
->deferred_len
+= len
;
1770 ssh
->deferred_data_size
+= pkt
->encrypted_len
;
1771 ssh_free_packet(pkt
);
1775 * Queue an SSH2 packet.
1777 static void ssh2_pkt_queue(Ssh ssh
, struct Packet
*pkt
)
1779 assert(ssh
->queueing
);
1781 if (ssh
->queuelen
>= ssh
->queuesize
) {
1782 ssh
->queuesize
= ssh
->queuelen
+ 32;
1783 ssh
->queue
= sresize(ssh
->queue
, ssh
->queuesize
, struct Packet
*);
1786 ssh
->queue
[ssh
->queuelen
++] = pkt
;
1790 * Either queue or send a packet, depending on whether queueing is
1793 static void ssh2_pkt_send(Ssh ssh
, struct Packet
*pkt
)
1796 ssh2_pkt_queue(ssh
, pkt
);
1798 ssh2_pkt_send_noqueue(ssh
, pkt
);
1803 * Either queue or defer a packet, depending on whether queueing is
1806 static void ssh2_pkt_defer(Ssh ssh
, struct Packet
*pkt
)
1809 ssh2_pkt_queue(ssh
, pkt
);
1811 ssh2_pkt_defer_noqueue(ssh
, pkt
);
1816 * Send the whole deferred data block constructed by
1817 * ssh2_pkt_defer() or SSH1's defer_packet().
1819 * The expected use of the defer mechanism is that you call
1820 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1821 * not currently queueing, this simply sets up deferred_send_data
1822 * and then sends it. If we _are_ currently queueing, the calls to
1823 * ssh2_pkt_defer() put the deferred packets on to the queue
1824 * instead, and therefore ssh_pkt_defersend() has no deferred data
1825 * to send. Hence, there's no need to make it conditional on
1828 static void ssh_pkt_defersend(Ssh ssh
)
1831 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1833 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1834 sfree(ssh
->deferred_send_data
);
1835 ssh
->deferred_send_data
= NULL
;
1836 if (backlog
> SSH_MAX_BACKLOG
)
1837 ssh_throttle_all(ssh
, 1, backlog
);
1839 ssh
->outgoing_data_size
+= ssh
->deferred_data_size
;
1840 if (!ssh
->kex_in_progress
&&
1841 ssh
->max_data_size
!= 0 &&
1842 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1843 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1844 ssh
->deferred_data_size
= 0;
1848 * Send all queued SSH2 packets. We send them by means of
1849 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1850 * packets that needed to be lumped together.
1852 static void ssh2_pkt_queuesend(Ssh ssh
)
1856 assert(!ssh
->queueing
);
1858 for (i
= 0; i
< ssh
->queuelen
; i
++)
1859 ssh2_pkt_defer_noqueue(ssh
, ssh
->queue
[i
]);
1862 ssh_pkt_defersend(ssh
);
1866 void bndebug(char *string
, Bignum b
)
1870 p
= ssh2_mpint_fmt(b
, &len
);
1871 debug(("%s", string
));
1872 for (i
= 0; i
< len
; i
++)
1873 debug((" %02x", p
[i
]));
1879 static void sha_mpint(SHA_State
* s
, Bignum b
)
1883 p
= ssh2_mpint_fmt(b
, &len
);
1884 sha_string(s
, p
, len
);
1889 * Packet decode functions for both SSH1 and SSH2.
1891 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
)
1893 unsigned long value
;
1894 if (pkt
->length
- pkt
->savedpos
< 4)
1895 return 0; /* arrgh, no way to decline (FIXME?) */
1896 value
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1900 static int ssh2_pkt_getbool(struct Packet
*pkt
)
1902 unsigned long value
;
1903 if (pkt
->length
- pkt
->savedpos
< 1)
1904 return 0; /* arrgh, no way to decline (FIXME?) */
1905 value
= pkt
->body
[pkt
->savedpos
] != 0;
1909 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
)
1914 if (pkt
->length
- pkt
->savedpos
< 4)
1916 len
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1921 if (pkt
->length
- pkt
->savedpos
< *length
)
1923 *p
= (char *)(pkt
->body
+ pkt
->savedpos
);
1924 pkt
->savedpos
+= *length
;
1926 static void *ssh_pkt_getdata(struct Packet
*pkt
, int length
)
1928 if (pkt
->length
- pkt
->savedpos
< length
)
1930 pkt
->savedpos
+= length
;
1931 return pkt
->body
+ (pkt
->savedpos
- length
);
1933 static int ssh1_pkt_getrsakey(struct Packet
*pkt
, struct RSAKey
*key
,
1934 unsigned char **keystr
)
1938 j
= makekey(pkt
->body
+ pkt
->savedpos
,
1939 pkt
->length
- pkt
->savedpos
,
1946 assert(pkt
->savedpos
< pkt
->length
);
1950 static Bignum
ssh1_pkt_getmp(struct Packet
*pkt
)
1955 j
= ssh1_read_bignum(pkt
->body
+ pkt
->savedpos
,
1956 pkt
->length
- pkt
->savedpos
, &b
);
1964 static Bignum
ssh2_pkt_getmp(struct Packet
*pkt
)
1970 ssh_pkt_getstring(pkt
, &p
, &length
);
1975 b
= bignum_from_bytes((unsigned char *)p
, length
);
1980 * Helper function to add an SSH2 signature blob to a packet.
1981 * Expects to be shown the public key blob as well as the signature
1982 * blob. Normally works just like ssh2_pkt_addstring, but will
1983 * fiddle with the signature packet if necessary for
1984 * BUG_SSH2_RSA_PADDING.
1986 static void ssh2_add_sigblob(Ssh ssh
, struct Packet
*pkt
,
1987 void *pkblob_v
, int pkblob_len
,
1988 void *sigblob_v
, int sigblob_len
)
1990 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1991 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1993 /* dmemdump(pkblob, pkblob_len); */
1994 /* dmemdump(sigblob, sigblob_len); */
1997 * See if this is in fact an ssh-rsa signature and a buggy
1998 * server; otherwise we can just do this the easy way.
2000 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
2001 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
2002 int pos
, len
, siglen
;
2005 * Find the byte length of the modulus.
2008 pos
= 4+7; /* skip over "ssh-rsa" */
2009 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
2010 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
2011 pos
+= 4; /* find modulus itself */
2012 while (len
> 0 && pkblob
[pos
] == 0)
2014 /* debug(("modulus length is %d\n", len)); */
2017 * Now find the signature integer.
2019 pos
= 4+7; /* skip over "ssh-rsa" */
2020 siglen
= GET_32BIT(sigblob
+pos
);
2021 /* debug(("signature length is %d\n", siglen)); */
2023 if (len
!= siglen
) {
2024 unsigned char newlen
[4];
2025 ssh2_pkt_addstring_start(pkt
);
2026 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, pos
);
2027 /* dmemdump(sigblob, pos); */
2028 pos
+= 4; /* point to start of actual sig */
2029 PUT_32BIT(newlen
, len
);
2030 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 4);
2031 /* dmemdump(newlen, 4); */
2033 while (len
-- > siglen
) {
2034 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 1);
2035 /* dmemdump(newlen, 1); */
2037 ssh2_pkt_addstring_data(pkt
, (char *)(sigblob
+pos
), siglen
);
2038 /* dmemdump(sigblob+pos, siglen); */
2042 /* Otherwise fall through and do it the easy way. */
2045 ssh2_pkt_addstring_start(pkt
);
2046 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, sigblob_len
);
2050 * Examine the remote side's version string and compare it against
2051 * a list of known buggy implementations.
2053 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
2055 char *imp
; /* pointer to implementation part */
2057 imp
+= strcspn(imp
, "-");
2059 imp
+= strcspn(imp
, "-");
2062 ssh
->remote_bugs
= 0;
2064 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
2065 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
2066 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
2067 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
2068 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
2069 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
2071 * These versions don't support SSH1_MSG_IGNORE, so we have
2072 * to use a different defence against password length
2075 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
2076 logevent("We believe remote version has SSH1 ignore bug");
2079 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
2080 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
2081 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
2083 * These versions need a plain password sent; they can't
2084 * handle having a null and a random length of data after
2087 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
2088 logevent("We believe remote version needs a plain SSH1 password");
2091 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
2092 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
2093 (!strcmp(imp
, "Cisco-1.25")))) {
2095 * These versions apparently have no clue whatever about
2096 * RSA authentication and will panic and die if they see
2097 * an AUTH_RSA message.
2099 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
2100 logevent("We believe remote version can't handle RSA authentication");
2103 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
2104 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
2105 !wc_match("* VShell", imp
) &&
2106 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
2107 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
2108 wc_match("2.1 *", imp
)))) {
2110 * These versions have the HMAC bug.
2112 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
2113 logevent("We believe remote version has SSH2 HMAC bug");
2116 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2117 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2118 !wc_match("* VShell", imp
) &&
2119 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2121 * These versions have the key-derivation bug (failing to
2122 * include the literal shared secret in the hashes that
2123 * generate the keys).
2125 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2126 logevent("We believe remote version has SSH2 key-derivation bug");
2129 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2130 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2131 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2132 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2134 * These versions have the SSH2 RSA padding bug.
2136 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2137 logevent("We believe remote version has SSH2 RSA padding bug");
2140 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2141 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2142 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2144 * These versions have the SSH2 session-ID bug in
2145 * public-key authentication.
2147 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2148 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2151 if (ssh
->cfg
.sshbug_rekey2
== FORCE_ON
||
2152 (ssh
->cfg
.sshbug_rekey2
== AUTO
&&
2153 (wc_match("OpenSSH_2.[0-4]*", imp
) ||
2154 wc_match("OpenSSH_2.5.[0-3]*", imp
) ||
2155 wc_match("Sun_SSH_1.0", imp
) ||
2156 wc_match("Sun_SSH_1.0.1", imp
)))) {
2158 * These versions have the SSH2 rekey bug.
2160 ssh
->remote_bugs
|= BUG_SSH2_REKEY
;
2161 logevent("We believe remote version has SSH2 rekey bug");
2166 * The `software version' part of an SSH version string is required
2167 * to contain no spaces or minus signs.
2169 static void ssh_fix_verstring(char *str
)
2171 /* Eat "SSH-<protoversion>-". */
2172 assert(*str
== 'S'); str
++;
2173 assert(*str
== 'S'); str
++;
2174 assert(*str
== 'H'); str
++;
2175 assert(*str
== '-'); str
++;
2176 while (*str
&& *str
!= '-') str
++;
2177 assert(*str
== '-'); str
++;
2179 /* Convert minus signs and spaces in the remaining string into
2182 if (*str
== '-' || *str
== ' ')
2188 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2190 struct do_ssh_init_state
{
2198 crState(do_ssh_init_state
);
2200 crBegin(ssh
->do_ssh_init_crstate
);
2202 /* Search for the string "SSH-" in the input. */
2205 static const int transS
[] = { 1, 2, 2, 1 };
2206 static const int transH
[] = { 0, 0, 3, 0 };
2207 static const int transminus
[] = { 0, 0, 0, -1 };
2209 s
->i
= transS
[s
->i
];
2211 s
->i
= transH
[s
->i
];
2213 s
->i
= transminus
[s
->i
];
2218 crReturn(1); /* get another character */
2222 s
->vstring
= snewn(s
->vstrsize
, char);
2223 strcpy(s
->vstring
, "SSH-");
2227 crReturn(1); /* get another char */
2228 if (s
->vslen
>= s
->vstrsize
- 1) {
2230 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2232 s
->vstring
[s
->vslen
++] = c
;
2235 s
->version
[s
->i
] = '\0';
2237 } else if (s
->i
< sizeof(s
->version
) - 1)
2238 s
->version
[s
->i
++] = c
;
2239 } else if (c
== '\012')
2243 ssh
->agentfwd_enabled
= FALSE
;
2244 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2246 s
->vstring
[s
->vslen
] = 0;
2247 s
->vstring
[strcspn(s
->vstring
, "\015\012")] = '\0';/* remove EOL chars */
2250 vlog
= snewn(20 + s
->vslen
, char);
2251 sprintf(vlog
, "Server version: %s", s
->vstring
);
2255 ssh_detect_bugs(ssh
, s
->vstring
);
2258 * Decide which SSH protocol version to support.
2261 /* Anything strictly below "2.0" means protocol 1 is supported. */
2262 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2263 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2264 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2266 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2267 bombout(("SSH protocol version 1 required by user but not provided by server"));
2270 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2271 bombout(("SSH protocol version 2 required by user but not provided by server"));
2278 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2280 * Construct a v2 version string.
2282 verstring
= dupprintf("SSH-2.0-%s\015\012", sshver
);
2286 * Construct a v1 version string.
2288 verstring
= dupprintf("SSH-%s-%s\012",
2289 (ssh_versioncmp(s
->version
, "1.5") <= 0 ?
2290 s
->version
: "1.5"),
2295 ssh_fix_verstring(verstring
);
2297 if (ssh
->version
== 2) {
2299 * Hash our version string and their version string.
2301 SHA_Init(&ssh
->exhashbase
);
2302 sha_string(&ssh
->exhashbase
, verstring
,
2303 strcspn(verstring
, "\015\012"));
2304 sha_string(&ssh
->exhashbase
, s
->vstring
,
2305 strcspn(s
->vstring
, "\015\012"));
2308 * Initialise SSHv2 protocol.
2310 ssh
->protocol
= ssh2_protocol
;
2311 ssh2_protocol_setup(ssh
);
2312 ssh
->s_rdpkt
= ssh2_rdpkt
;
2315 * Initialise SSHv1 protocol.
2317 ssh
->protocol
= ssh1_protocol
;
2318 ssh1_protocol_setup(ssh
);
2319 ssh
->s_rdpkt
= ssh1_rdpkt
;
2321 logeventf(ssh
, "We claim version: %.*s",
2322 strcspn(verstring
, "\015\012"), verstring
);
2323 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2327 logeventf(ssh
, "Using SSH protocol version %d", ssh
->version
);
2329 update_specials_menu(ssh
->frontend
);
2330 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2331 ssh
->pinger
= pinger_new(&ssh
->cfg
, &ssh_backend
, ssh
);
2338 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2340 crBegin(ssh
->ssh_gotdata_crstate
);
2343 * To begin with, feed the characters one by one to the
2344 * protocol initialisation / selection function do_ssh_init().
2345 * When that returns 0, we're done with the initial greeting
2346 * exchange and can move on to packet discipline.
2349 int ret
; /* need not be kept across crReturn */
2351 crReturnV
; /* more data please */
2352 ret
= do_ssh_init(ssh
, *data
);
2360 * We emerge from that loop when the initial negotiation is
2361 * over and we have selected an s_rdpkt function. Now pass
2362 * everything to s_rdpkt, and then pass the resulting packets
2363 * to the proper protocol handler.
2368 while (datalen
> 0) {
2369 struct Packet
*pktin
= ssh
->s_rdpkt(ssh
, &data
, &datalen
);
2371 ssh
->protocol(ssh
, NULL
, 0, pktin
);
2372 ssh_free_packet(pktin
);
2374 if (ssh
->state
== SSH_STATE_CLOSED
)
2382 static int ssh_do_close(Ssh ssh
, int notify_exit
)
2385 struct ssh_channel
*c
;
2387 ssh
->state
= SSH_STATE_CLOSED
;
2392 notify_remote_exit(ssh
->frontend
);
2397 * Now we must shut down any port and X forwardings going
2398 * through this connection.
2400 if (ssh
->channels
) {
2401 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2404 x11_close(c
->u
.x11
.s
);
2407 pfd_close(c
->u
.pfd
.s
);
2410 del234(ssh
->channels
, c
);
2411 if (ssh
->version
== 2)
2412 bufchain_clear(&c
->v
.v2
.outbuffer
);
2420 static void ssh_log(Plug plug
, int type
, SockAddr addr
, int port
,
2421 const char *error_msg
, int error_code
)
2423 Ssh ssh
= (Ssh
) plug
;
2424 char addrbuf
[256], *msg
;
2426 sk_getaddr(addr
, addrbuf
, lenof(addrbuf
));
2429 msg
= dupprintf("Connecting to %s port %d", addrbuf
, port
);
2431 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 /* A socket error has occurred. */
2448 logevent(error_msg
);
2449 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2451 logevent("Server closed network connection");
2454 notify_remote_exit(ssh
->frontend
);
2458 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2460 Ssh ssh
= (Ssh
) plug
;
2461 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2462 if (ssh
->state
== SSH_STATE_CLOSED
) {
2463 ssh_do_close(ssh
, TRUE
);
2469 static void ssh_sent(Plug plug
, int bufsize
)
2471 Ssh ssh
= (Ssh
) plug
;
2473 * If the send backlog on the SSH socket itself clears, we
2474 * should unthrottle the whole world if it was throttled.
2476 if (bufsize
< SSH_MAX_BACKLOG
)
2477 ssh_throttle_all(ssh
, 0, bufsize
);
2481 * Connect to specified host and port.
2482 * Returns an error message, or NULL on success.
2483 * Also places the canonical host name into `realhost'. It must be
2484 * freed by the caller.
2486 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2487 char **realhost
, int nodelay
, int keepalive
)
2489 static const struct plug_function_table fn_table
= {
2500 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2501 if (!ssh
->savedhost
)
2502 fatalbox("Out of memory");
2503 strcpy(ssh
->savedhost
, host
);
2506 port
= 22; /* default ssh port */
2507 ssh
->savedport
= port
;
2512 logeventf(ssh
, "Looking up host \"%s\"%s", host
,
2513 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV4 ?
" (IPv4)" :
2514 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV6 ?
" (IPv6)" : "")));
2515 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
,
2516 ssh
->cfg
.addressfamily
);
2517 if ((err
= sk_addr_error(addr
)) != NULL
) {
2525 ssh
->fn
= &fn_table
;
2526 ssh
->s
= new_connection(addr
, *realhost
, port
,
2527 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2528 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2530 notify_remote_exit(ssh
->frontend
);
2538 * Throttle or unthrottle the SSH connection.
2540 static void ssh1_throttle(Ssh ssh
, int adjust
)
2542 int old_count
= ssh
->v1_throttle_count
;
2543 ssh
->v1_throttle_count
+= adjust
;
2544 assert(ssh
->v1_throttle_count
>= 0);
2545 if (ssh
->v1_throttle_count
&& !old_count
) {
2546 sk_set_frozen(ssh
->s
, 1);
2547 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2548 sk_set_frozen(ssh
->s
, 0);
2553 * Throttle or unthrottle _all_ local data streams (for when sends
2554 * on the SSH connection itself back up).
2556 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2559 struct ssh_channel
*c
;
2561 if (enable
== ssh
->throttled_all
)
2563 ssh
->throttled_all
= enable
;
2564 ssh
->overall_bufsize
= bufsize
;
2567 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2569 case CHAN_MAINSESSION
:
2571 * This is treated separately, outside the switch.
2575 x11_override_throttle(c
->u
.x11
.s
, enable
);
2578 /* Agent channels require no buffer management. */
2581 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2588 * Username and password input, abstracted off into routines
2589 * reusable in several places - even between SSH1 and SSH2.
2592 /* Set up a username or password input loop on a given buffer. */
2593 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2595 ssh
->userpass_input_buffer
= buffer
;
2596 ssh
->userpass_input_buflen
= buflen
;
2597 ssh
->userpass_input_bufpos
= 0;
2598 ssh
->userpass_input_echo
= echo
;
2602 * Process some terminal data in the course of username/password
2603 * input. Returns >0 for success (line of input returned in
2604 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2605 * for inconclusive (keep waiting for more input please).
2607 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2612 switch (c
= *in
++) {
2615 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2616 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2621 if (ssh
->userpass_input_bufpos
> 0) {
2622 if (ssh
->userpass_input_echo
)
2623 c_write_str(ssh
, "\b \b");
2624 ssh
->userpass_input_bufpos
--;
2629 while (ssh
->userpass_input_bufpos
> 0) {
2630 if (ssh
->userpass_input_echo
)
2631 c_write_str(ssh
, "\b \b");
2632 ssh
->userpass_input_bufpos
--;
2641 * This simplistic check for printability is disabled
2642 * when we're doing password input, because some people
2643 * have control characters in their passwords.o
2645 if ((!ssh
->userpass_input_echo
||
2646 (c
>= ' ' && c
<= '~') ||
2647 ((unsigned char) c
>= 160))
2648 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2649 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2650 if (ssh
->userpass_input_echo
)
2651 c_write(ssh
, &c
, 1);
2659 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2661 Ssh ssh
= (Ssh
) sshv
;
2663 ssh
->agent_response
= reply
;
2664 ssh
->agent_response_len
= replylen
;
2666 if (ssh
->version
== 1)
2667 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2669 do_ssh2_authconn(ssh
, NULL
, -1, NULL
);
2672 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2674 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2676 void *sentreply
= reply
;
2679 /* Fake SSH_AGENT_FAILURE. */
2680 sentreply
= "\0\0\0\1\5";
2683 if (ssh
->version
== 2) {
2684 ssh2_add_channel_data(c
, sentreply
, replylen
);
2687 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2688 PKT_INT
, c
->remoteid
,
2691 PKT_DATA
, sentreply
, replylen
,
2700 * Handle the key exchange and user authentication phases.
2702 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
2703 struct Packet
*pktin
)
2706 unsigned char cookie
[8], *ptr
;
2707 struct RSAKey servkey
, hostkey
;
2708 struct MD5Context md5c
;
2709 struct do_ssh1_login_state
{
2711 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2712 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2713 int tried_publickey
, tried_agent
;
2714 int tis_auth_refused
, ccard_auth_refused
;
2715 unsigned char session_id
[16];
2718 void *publickey_blob
;
2719 int publickey_bloblen
;
2725 unsigned char request
[5], *response
, *p
;
2734 crState(do_ssh1_login_state
);
2736 crBegin(ssh
->do_ssh1_login_crstate
);
2741 if (pktin
->type
!= SSH1_SMSG_PUBLIC_KEY
) {
2742 bombout(("Public key packet not received"));
2746 logevent("Received public keys");
2748 ptr
= ssh_pkt_getdata(pktin
, 8);
2750 bombout(("SSH1 public key packet stopped before random cookie"));
2753 memcpy(cookie
, ptr
, 8);
2755 if (!ssh1_pkt_getrsakey(pktin
, &servkey
, &s
->keystr1
) ||
2756 !ssh1_pkt_getrsakey(pktin
, &hostkey
, &s
->keystr2
)) {
2757 bombout(("Failed to read SSH1 public keys from public key packet"));
2762 * Log the host key fingerprint.
2766 logevent("Host key fingerprint is:");
2767 strcpy(logmsg
, " ");
2768 hostkey
.comment
= NULL
;
2769 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2770 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2774 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(pktin
);
2775 s
->supported_ciphers_mask
= ssh_pkt_getuint32(pktin
);
2776 s
->supported_auths_mask
= ssh_pkt_getuint32(pktin
);
2778 ssh
->v1_local_protoflags
=
2779 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2780 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2783 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2784 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2785 MD5Update(&md5c
, cookie
, 8);
2786 MD5Final(s
->session_id
, &md5c
);
2788 for (i
= 0; i
< 32; i
++)
2789 ssh
->session_key
[i
] = random_byte();
2792 * Verify that the `bits' and `bytes' parameters match.
2794 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
2795 servkey
.bits
> servkey
.bytes
* 8) {
2796 bombout(("SSH1 public keys were badly formatted"));
2800 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2802 s
->rsabuf
= snewn(s
->len
, unsigned char);
2804 fatalbox("Out of memory");
2807 * Verify the host key.
2811 * First format the key into a string.
2813 int len
= rsastr_len(&hostkey
);
2814 char fingerprint
[100];
2815 char *keystr
= snewn(len
, char);
2817 fatalbox("Out of memory");
2818 rsastr_fmt(keystr
, &hostkey
);
2819 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2820 verify_ssh_host_key(ssh
->frontend
,
2821 ssh
->savedhost
, ssh
->savedport
, "rsa", keystr
,
2826 for (i
= 0; i
< 32; i
++) {
2827 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2829 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2832 if (hostkey
.bytes
> servkey
.bytes
) {
2833 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
2835 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2837 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2839 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2842 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2846 logevent("Encrypted session key");
2849 int cipher_chosen
= 0, warn
= 0;
2850 char *cipher_string
= NULL
;
2852 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2853 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
2854 if (next_cipher
== CIPHER_WARN
) {
2855 /* If/when we choose a cipher, warn about it */
2857 } else if (next_cipher
== CIPHER_AES
) {
2858 /* XXX Probably don't need to mention this. */
2859 logevent("AES not supported in SSH1, skipping");
2861 switch (next_cipher
) {
2862 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2863 cipher_string
= "3DES"; break;
2864 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2865 cipher_string
= "Blowfish"; break;
2866 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2867 cipher_string
= "single-DES"; break;
2869 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2873 if (!cipher_chosen
) {
2874 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2875 bombout(("Server violates SSH 1 protocol by not "
2876 "supporting 3DES encryption"));
2878 /* shouldn't happen */
2879 bombout(("No supported ciphers found"));
2883 /* Warn about chosen cipher if necessary. */
2885 sk_set_frozen(ssh
->s
, 1);
2886 askalg(ssh
->frontend
, "cipher", cipher_string
);
2887 sk_set_frozen(ssh
->s
, 0);
2891 switch (s
->cipher_type
) {
2892 case SSH_CIPHER_3DES
:
2893 logevent("Using 3DES encryption");
2895 case SSH_CIPHER_DES
:
2896 logevent("Using single-DES encryption");
2898 case SSH_CIPHER_BLOWFISH
:
2899 logevent("Using Blowfish encryption");
2903 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
2904 PKT_CHAR
, s
->cipher_type
,
2905 PKT_DATA
, cookie
, 8,
2906 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
2907 PKT_DATA
, s
->rsabuf
, s
->len
,
2908 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
2910 logevent("Trying to enable encryption...");
2914 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2915 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
2917 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
2918 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
2919 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
2921 ssh
->crcda_ctx
= crcda_make_context();
2922 logevent("Installing CRC compensation attack detector");
2924 if (servkey
.modulus
) {
2925 sfree(servkey
.modulus
);
2926 servkey
.modulus
= NULL
;
2928 if (servkey
.exponent
) {
2929 sfree(servkey
.exponent
);
2930 servkey
.exponent
= NULL
;
2932 if (hostkey
.modulus
) {
2933 sfree(hostkey
.modulus
);
2934 hostkey
.modulus
= NULL
;
2936 if (hostkey
.exponent
) {
2937 sfree(hostkey
.exponent
);
2938 hostkey
.exponent
= NULL
;
2942 if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
2943 bombout(("Encryption not successfully enabled"));
2947 logevent("Successfully started encryption");
2951 if (!*ssh
->cfg
.username
) {
2952 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2953 if (!ssh_get_line("login as: ",
2954 s
->username
, sizeof(s
->username
), FALSE
)) {
2956 * get_line failed to get a username.
2959 logevent("No username provided. Abandoning session.");
2960 ssh
->close_expected
= TRUE
;
2961 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2965 int ret
; /* need not be kept over crReturn */
2966 c_write_str(ssh
, "login as: ");
2969 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
2971 crWaitUntil(!pktin
);
2972 ret
= process_userpass_input(ssh
, in
, inlen
);
2976 c_write_str(ssh
, "\r\n");
2979 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
2980 s
->username
[sizeof(s
->username
)-1] = '\0';
2983 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
2985 char userlog
[22 + sizeof(s
->username
)];
2986 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
2988 if (flags
& FLAG_INTERACTIVE
&&
2989 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2990 strcat(userlog
, "\r\n");
2991 c_write_str(ssh
, userlog
);
2998 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2999 /* We must not attempt PK auth. Pretend we've already tried it. */
3000 s
->tried_publickey
= s
->tried_agent
= 1;
3002 s
->tried_publickey
= s
->tried_agent
= 0;
3004 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
3005 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
3006 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
3007 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
3008 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
3009 s
->publickey_blob
= NULL
;
3011 s
->publickey_blob
= NULL
;
3013 while (pktin
->type
== SSH1_SMSG_FAILURE
) {
3014 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
3016 if (agent_exists() && !s
->tried_agent
) {
3018 * Attempt RSA authentication using Pageant.
3024 logevent("Pageant is running. Requesting keys.");
3026 /* Request the keys held by the agent. */
3027 PUT_32BIT(s
->request
, 1);
3028 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
3029 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
3030 ssh_agent_callback
, ssh
)) {
3034 bombout(("Unexpected data from server while waiting"
3035 " for agent response"));
3038 } while (pktin
|| inlen
> 0);
3039 r
= ssh
->agent_response
;
3040 s
->responselen
= ssh
->agent_response_len
;
3042 s
->response
= (unsigned char *) r
;
3043 if (s
->response
&& s
->responselen
>= 5 &&
3044 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
3045 s
->p
= s
->response
+ 5;
3046 s
->nkeys
= GET_32BIT(s
->p
);
3050 sprintf(buf
, "Pageant has %d SSH1 keys", s
->nkeys
);
3053 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
3056 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
3059 if (s
->publickey_blob
&&
3060 !memcmp(s
->p
, s
->publickey_blob
,
3061 s
->publickey_bloblen
)) {
3062 logevent("This key matches configured key file");
3063 s
->tried_publickey
= 1;
3068 do { /* do while (0) to make breaking easy */
3069 n
= ssh1_read_bignum
3070 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3075 n
= ssh1_read_bignum
3076 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3081 if (s
->responselen
- (s
->p
-s
->response
) < 4)
3083 s
->commentlen
= GET_32BIT(s
->p
);
3085 if (s
->responselen
- (s
->p
-s
->response
) <
3088 s
->commentp
= (char *)s
->p
;
3089 s
->p
+= s
->commentlen
;
3093 logevent("Pageant key list packet was truncated");
3097 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3098 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3100 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3101 logevent("Key refused");
3104 logevent("Received RSA challenge");
3105 if ((s
->challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3106 bombout(("Server's RSA challenge was badly formatted"));
3111 char *agentreq
, *q
, *ret
;
3114 len
= 1 + 4; /* message type, bit count */
3115 len
+= ssh1_bignum_length(s
->key
.exponent
);
3116 len
+= ssh1_bignum_length(s
->key
.modulus
);
3117 len
+= ssh1_bignum_length(s
->challenge
);
3118 len
+= 16; /* session id */
3119 len
+= 4; /* response format */
3120 agentreq
= snewn(4 + len
, char);
3121 PUT_32BIT(agentreq
, len
);
3123 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
3124 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
3126 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
3127 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
3128 q
+= ssh1_write_bignum(q
, s
->challenge
);
3129 memcpy(q
, s
->session_id
, 16);
3131 PUT_32BIT(q
, 1); /* response format */
3132 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
3133 ssh_agent_callback
, ssh
)) {
3138 bombout(("Unexpected data from server"
3139 " while waiting for agent"
3143 } while (pktin
|| inlen
> 0);
3144 vret
= ssh
->agent_response
;
3145 retlen
= ssh
->agent_response_len
;
3150 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
3151 logevent("Sending Pageant's response");
3152 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3153 PKT_DATA
, ret
+ 5, 16,
3157 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
3159 ("Pageant's response accepted");
3160 if (flags
& FLAG_VERBOSE
) {
3161 c_write_str(ssh
, "Authenticated using"
3163 c_write(ssh
, s
->commentp
,
3165 c_write_str(ssh
, "\" from agent\r\n");
3170 ("Pageant's response not accepted");
3173 ("Pageant failed to answer challenge");
3177 logevent("No reply received from Pageant");
3180 freebn(s
->key
.exponent
);
3181 freebn(s
->key
.modulus
);
3182 freebn(s
->challenge
);
3191 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
3192 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
3194 if (ssh
->cfg
.try_tis_auth
&&
3195 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3196 !s
->tis_auth_refused
) {
3197 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3198 logevent("Requested TIS authentication");
3199 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3201 if (pktin
->type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3202 logevent("TIS authentication declined");
3203 if (flags
& FLAG_INTERACTIVE
)
3204 c_write_str(ssh
, "TIS authentication refused.\r\n");
3205 s
->tis_auth_refused
= 1;
3211 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3213 bombout(("TIS challenge packet was badly formed"));
3216 logevent("Received TIS challenge");
3217 if (challengelen
> sizeof(s
->prompt
) - 1)
3218 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3219 memcpy(s
->prompt
, challenge
, challengelen
);
3220 /* Prompt heuristic comes from OpenSSH */
3221 strncpy(s
->prompt
+ challengelen
,
3222 memchr(s
->prompt
, '\n', challengelen
) ?
3223 "": "\r\nResponse: ",
3224 (sizeof s
->prompt
) - challengelen
);
3225 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
3228 if (ssh
->cfg
.try_tis_auth
&&
3229 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3230 !s
->ccard_auth_refused
) {
3231 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3232 logevent("Requested CryptoCard authentication");
3233 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3235 if (pktin
->type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3236 logevent("CryptoCard authentication declined");
3237 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3238 s
->ccard_auth_refused
= 1;
3244 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3246 bombout(("CryptoCard challenge packet was badly formed"));
3249 logevent("Received CryptoCard challenge");
3250 if (challengelen
> sizeof(s
->prompt
) - 1)
3251 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3252 memcpy(s
->prompt
, challenge
, challengelen
);
3253 strncpy(s
->prompt
+ challengelen
,
3254 memchr(s
->prompt
, '\n', challengelen
) ?
3255 "" : "\r\nResponse: ",
3256 sizeof(s
->prompt
) - challengelen
);
3257 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
3260 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3261 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
3262 s
->username
, ssh
->savedhost
);
3264 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3265 char *comment
= NULL
;
3268 if (flags
& FLAG_VERBOSE
)
3269 c_write_str(ssh
, "Trying public key authentication.\r\n");
3270 logeventf(ssh
, "Trying public key \"%s\"",
3271 filename_to_str(&ssh
->cfg
.keyfile
));
3272 type
= key_type(&ssh
->cfg
.keyfile
);
3273 if (type
!= SSH_KEYTYPE_SSH1
) {
3274 sprintf(msgbuf
, "Key is of wrong type (%s)",
3275 key_type_to_str(type
));
3277 c_write_str(ssh
, msgbuf
);
3278 c_write_str(ssh
, "\r\n");
3279 s
->tried_publickey
= 1;
3282 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
3283 if (flags
& FLAG_VERBOSE
)
3284 c_write_str(ssh
, "No passphrase required.\r\n");
3287 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
3292 * Show password prompt, having first obtained it via a TIS
3293 * or CryptoCard exchange if we're doing TIS or CryptoCard
3297 if (!ssh_get_line(s
->prompt
, s
->password
,
3298 sizeof(s
->password
), TRUE
)) {
3300 * get_line failed to get a password (for example
3301 * because one was supplied on the command line
3302 * which has already failed to work). Terminate.
3304 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
3305 PKT_STR
, "No more passwords available to try",
3307 logevent("Unable to authenticate");
3308 connection_fatal(ssh
->frontend
, "Unable to authenticate");
3309 ssh
->close_expected
= TRUE
;
3310 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3314 /* Prompt may have come from server. We've munged it a bit, so
3315 * we know it to be zero-terminated at least once. */
3316 int ret
; /* need not be saved over crReturn */
3317 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3320 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3322 crWaitUntil(!pktin
);
3323 ret
= process_userpass_input(ssh
, in
, inlen
);
3327 c_write_str(ssh
, "\r\n");
3331 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3333 * Try public key authentication with the specified
3336 s
->tried_publickey
= 1;
3339 const char *error
= NULL
;
3340 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3343 c_write_str(ssh
, "Couldn't load private key from ");
3344 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3345 c_write_str(ssh
, " (");
3346 c_write_str(ssh
, error
);
3347 c_write_str(ssh
, ").\r\n");
3348 continue; /* go and try password */
3351 c_write_str(ssh
, "Wrong passphrase.\r\n");
3352 s
->tried_publickey
= 0;
3353 continue; /* try again */
3358 * Send a public key attempt.
3360 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3361 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3364 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3365 c_write_str(ssh
, "Server refused our public key.\r\n");
3366 continue; /* go and try password */
3368 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3369 bombout(("Bizarre response to offer of public key"));
3375 unsigned char buffer
[32];
3376 Bignum challenge
, response
;
3378 if ((challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3379 bombout(("Server's RSA challenge was badly formatted"));
3382 response
= rsadecrypt(challenge
, &s
->key
);
3383 freebn(s
->key
.private_exponent
);/* burn the evidence */
3385 for (i
= 0; i
< 32; i
++) {
3386 buffer
[i
] = bignum_byte(response
, 31 - i
);
3390 MD5Update(&md5c
, buffer
, 32);
3391 MD5Update(&md5c
, s
->session_id
, 16);
3392 MD5Final(buffer
, &md5c
);
3394 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3395 PKT_DATA
, buffer
, 16, PKT_END
);
3402 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3403 if (flags
& FLAG_VERBOSE
)
3404 c_write_str(ssh
, "Failed to authenticate with"
3405 " our public key.\r\n");
3406 continue; /* go and try password */
3407 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3408 bombout(("Bizarre response to RSA authentication response"));
3412 break; /* we're through! */
3414 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3416 * Defence against traffic analysis: we send a
3417 * whole bunch of packets containing strings of
3418 * different lengths. One of these strings is the
3419 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3420 * The others are all random data in
3421 * SSH1_MSG_IGNORE packets. This way a passive
3422 * listener can't tell which is the password, and
3423 * hence can't deduce the password length.
3425 * Anybody with a password length greater than 16
3426 * bytes is going to have enough entropy in their
3427 * password that a listener won't find it _that_
3428 * much help to know how long it is. So what we'll
3431 * - if password length < 16, we send 15 packets
3432 * containing string lengths 1 through 15
3434 * - otherwise, we let N be the nearest multiple
3435 * of 8 below the password length, and send 8
3436 * packets containing string lengths N through
3437 * N+7. This won't obscure the order of
3438 * magnitude of the password length, but it will
3439 * introduce a bit of extra uncertainty.
3441 * A few servers (the old 1.2.18 through 1.2.22)
3442 * can't deal with SSH1_MSG_IGNORE. For these
3443 * servers, we need an alternative defence. We make
3444 * use of the fact that the password is interpreted
3445 * as a C string: so we can append a NUL, then some
3448 * One server (a Cisco one) can deal with neither
3449 * SSH1_MSG_IGNORE _nor_ a padded password string.
3450 * For this server we are left with no defences
3451 * against password length sniffing.
3453 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3455 * The server can deal with SSH1_MSG_IGNORE, so
3456 * we can use the primary defence.
3458 int bottom
, top
, pwlen
, i
;
3461 pwlen
= strlen(s
->password
);
3463 bottom
= 0; /* zero length passwords are OK! :-) */
3466 bottom
= pwlen
& ~7;
3470 assert(pwlen
>= bottom
&& pwlen
<= top
);
3472 randomstr
= snewn(top
+ 1, char);
3474 for (i
= bottom
; i
<= top
; i
++) {
3476 defer_packet(ssh
, s
->pwpkt_type
,
3477 PKTT_PASSWORD
, PKT_STR
, s
->password
,
3478 PKTT_OTHER
, PKT_END
);
3480 for (j
= 0; j
< i
; j
++) {
3482 randomstr
[j
] = random_byte();
3483 } while (randomstr
[j
] == '\0');
3485 randomstr
[i
] = '\0';
3486 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3487 PKT_STR
, randomstr
, PKT_END
);
3490 logevent("Sending password with camouflage packets");
3491 ssh_pkt_defersend(ssh
);
3494 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3496 * The server can't deal with SSH1_MSG_IGNORE
3497 * but can deal with padded passwords, so we
3498 * can use the secondary defence.
3504 len
= strlen(s
->password
);
3505 if (len
< sizeof(string
)) {
3507 strcpy(string
, s
->password
);
3508 len
++; /* cover the zero byte */
3509 while (len
< sizeof(string
)) {
3510 string
[len
++] = (char) random_byte();
3515 logevent("Sending length-padded password");
3516 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3517 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3518 PKTT_OTHER
, PKT_END
);
3521 * The server has _both_
3522 * BUG_CHOKES_ON_SSH1_IGNORE and
3523 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3524 * therefore nothing we can do.
3527 len
= strlen(s
->password
);
3528 logevent("Sending unpadded password");
3529 send_packet(ssh
, s
->pwpkt_type
,
3530 PKTT_PASSWORD
, PKT_INT
, len
,
3531 PKT_DATA
, s
->password
, len
,
3532 PKTT_OTHER
, PKT_END
);
3535 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3536 PKT_STR
, s
->password
, PKTT_OTHER
, PKT_END
);
3539 logevent("Sent password");
3540 memset(s
->password
, 0, strlen(s
->password
));
3542 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3543 if (flags
& FLAG_VERBOSE
)
3544 c_write_str(ssh
, "Access denied\r\n");
3545 logevent("Authentication refused");
3546 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3547 bombout(("Strange packet received, type %d", pktin
->type
));
3552 logevent("Authentication successful");
3557 void sshfwd_close(struct ssh_channel
*c
)
3561 if (ssh
->state
!= SSH_STATE_SESSION
) {
3562 assert(ssh
->state
== SSH_STATE_CLOSED
);
3566 if (c
&& !c
->closes
) {
3568 * If the channel's remoteid is -1, we have sent
3569 * CHANNEL_OPEN for this channel, but it hasn't even been
3570 * acknowledged by the server. So we must set a close flag
3571 * on it now, and then when the server acks the channel
3572 * open, we can close it then.
3574 if (((int)c
->remoteid
) != -1) {
3575 if (ssh
->version
== 1) {
3576 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3579 struct Packet
*pktout
;
3580 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3581 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
3582 ssh2_pkt_send(ssh
, pktout
);
3585 c
->closes
= 1; /* sent MSG_CLOSE */
3586 if (c
->type
== CHAN_X11
) {
3588 logevent("Forwarded X11 connection terminated");
3589 } else if (c
->type
== CHAN_SOCKDATA
||
3590 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3592 logevent("Forwarded port closed");
3597 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3601 if (ssh
->state
!= SSH_STATE_SESSION
) {
3602 assert(ssh
->state
== SSH_STATE_CLOSED
);
3606 if (ssh
->version
== 1) {
3607 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3608 PKT_INT
, c
->remoteid
,
3610 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3611 PKTT_OTHER
, PKT_END
);
3613 * In SSH1 we can return 0 here - implying that forwarded
3614 * connections are never individually throttled - because
3615 * the only circumstance that can cause throttling will be
3616 * the whole SSH connection backing up, in which case
3617 * _everything_ will be throttled as a whole.
3621 ssh2_add_channel_data(c
, buf
, len
);
3622 return ssh2_try_send(c
);
3626 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3630 if (ssh
->state
!= SSH_STATE_SESSION
) {
3631 assert(ssh
->state
== SSH_STATE_CLOSED
);
3635 if (ssh
->version
== 1) {
3636 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3637 c
->v
.v1
.throttling
= 0;
3638 ssh1_throttle(ssh
, -1);
3641 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3645 static void ssh_queueing_handler(Ssh ssh
, struct Packet
*pktin
)
3647 struct queued_handler
*qh
= ssh
->qhead
;
3651 assert(pktin
->type
== qh
->msg1
|| pktin
->type
== qh
->msg2
);
3654 assert(ssh
->packet_dispatch
[qh
->msg1
] == ssh_queueing_handler
);
3655 ssh
->packet_dispatch
[qh
->msg1
] = NULL
;
3658 assert(ssh
->packet_dispatch
[qh
->msg2
] == ssh_queueing_handler
);
3659 ssh
->packet_dispatch
[qh
->msg2
] = NULL
;
3663 ssh
->qhead
= qh
->next
;
3665 if (ssh
->qhead
->msg1
> 0) {
3666 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg1
] == NULL
);
3667 ssh
->packet_dispatch
[ssh
->qhead
->msg1
] = ssh_queueing_handler
;
3669 if (ssh
->qhead
->msg2
> 0) {
3670 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg2
] == NULL
);
3671 ssh
->packet_dispatch
[ssh
->qhead
->msg2
] = ssh_queueing_handler
;
3674 ssh
->qhead
= ssh
->qtail
= NULL
;
3675 ssh
->packet_dispatch
[pktin
->type
] = NULL
;
3678 qh
->handler(ssh
, pktin
, qh
->ctx
);
3683 static void ssh_queue_handler(Ssh ssh
, int msg1
, int msg2
,
3684 chandler_fn_t handler
, void *ctx
)
3686 struct queued_handler
*qh
;
3688 qh
= snew(struct queued_handler
);
3691 qh
->handler
= handler
;
3695 if (ssh
->qtail
== NULL
) {
3699 assert(ssh
->packet_dispatch
[qh
->msg1
] == NULL
);
3700 ssh
->packet_dispatch
[qh
->msg1
] = ssh_queueing_handler
;
3703 assert(ssh
->packet_dispatch
[qh
->msg2
] == NULL
);
3704 ssh
->packet_dispatch
[qh
->msg2
] = ssh_queueing_handler
;
3707 ssh
->qtail
->next
= qh
;
3712 static void ssh_rportfwd_succfail(Ssh ssh
, struct Packet
*pktin
, void *ctx
)
3714 struct ssh_rportfwd
*rpf
, *pf
= (struct ssh_rportfwd
*)ctx
;
3716 if (pktin
->type
== (ssh
->version
== 1 ? SSH1_SMSG_SUCCESS
:
3717 SSH2_MSG_REQUEST_SUCCESS
)) {
3718 logeventf(ssh
, "Remote port forwarding from %s enabled",
3721 logeventf(ssh
, "Remote port forwarding from %s refused",
3724 rpf
= del234(ssh
->rportfwds
, pf
);
3730 static void ssh_setup_portfwd(Ssh ssh
, const Config
*cfg
)
3732 const char *portfwd_strptr
= cfg
->portfwd
;
3733 struct ssh_portfwd
*epf
;
3736 if (!ssh
->portfwds
) {
3737 ssh
->portfwds
= newtree234(ssh_portcmp
);
3740 * Go through the existing port forwardings and tag them
3741 * with status==DESTROY. Any that we want to keep will be
3742 * re-enabled (status==KEEP) as we go through the
3743 * configuration and find out which bits are the same as
3746 struct ssh_portfwd
*epf
;
3748 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3749 epf
->status
= DESTROY
;
3752 while (*portfwd_strptr
) {
3753 char address_family
, type
;
3754 int sport
,dport
,sserv
,dserv
;
3755 char sports
[256], dports
[256], saddr
[256], host
[256];
3758 address_family
= 'A';
3760 if (*portfwd_strptr
== 'A' ||
3761 *portfwd_strptr
== '4' ||
3762 *portfwd_strptr
== '6')
3763 address_family
= *portfwd_strptr
++;
3764 if (*portfwd_strptr
== 'L' ||
3765 *portfwd_strptr
== 'R' ||
3766 *portfwd_strptr
== 'D')
3767 type
= *portfwd_strptr
++;
3772 while (*portfwd_strptr
&& *portfwd_strptr
!= '\t') {
3773 if (*portfwd_strptr
== ':') {
3775 * We've seen a colon in the middle of the
3776 * source port number. This means that
3777 * everything we've seen until now is the
3778 * source _address_, so we'll move it into
3779 * saddr and start sports from the beginning
3784 if (ssh
->version
== 1 && type
== 'R') {
3785 logeventf(ssh
, "SSH1 cannot handle remote source address "
3786 "spec \"%s\"; ignoring", sports
);
3788 strcpy(saddr
, sports
);
3791 if (n
< 255) sports
[n
++] = *portfwd_strptr
++;
3795 if (*portfwd_strptr
== '\t')
3798 while (*portfwd_strptr
&& *portfwd_strptr
!= ':') {
3799 if (n
< 255) host
[n
++] = *portfwd_strptr
++;
3802 if (*portfwd_strptr
== ':')
3805 while (*portfwd_strptr
) {
3806 if (n
< 255) dports
[n
++] = *portfwd_strptr
++;
3810 dport
= atoi(dports
);
3814 dport
= net_service_lookup(dports
);
3816 logeventf(ssh
, "Service lookup failed for destination"
3817 " port \"%s\"", dports
);
3821 while (*portfwd_strptr
) portfwd_strptr
++;
3823 portfwd_strptr
++; /* eat the NUL and move to next one */
3825 sport
= atoi(sports
);
3829 sport
= net_service_lookup(sports
);
3831 logeventf(ssh
, "Service lookup failed for source"
3832 " port \"%s\"", sports
);
3835 if (sport
&& dport
) {
3836 /* Set up a description of the source port. */
3837 struct ssh_portfwd
*pfrec
, *epfrec
;
3839 pfrec
= snew(struct ssh_portfwd
);
3841 pfrec
->saddr
= *saddr ?
dupstr(saddr
) : NULL
;
3842 pfrec
->sserv
= sserv ?
dupstr(sports
) : NULL
;
3843 pfrec
->sport
= sport
;
3844 pfrec
->daddr
= *host ?
dupstr(host
) : NULL
;
3845 pfrec
->dserv
= dserv ?
dupstr(dports
) : NULL
;
3846 pfrec
->dport
= dport
;
3847 pfrec
->local
= NULL
;
3848 pfrec
->remote
= NULL
;
3849 pfrec
->addressfamily
= (address_family
== '4' ? ADDRTYPE_IPV4
:
3850 address_family
== '6' ? ADDRTYPE_IPV6
:
3853 epfrec
= add234(ssh
->portfwds
, pfrec
);
3854 if (epfrec
!= pfrec
) {
3856 * We already have a port forwarding with precisely
3857 * these parameters. Hence, no need to do anything;
3858 * simply tag the existing one as KEEP.
3860 epfrec
->status
= KEEP
;
3861 free_portfwd(pfrec
);
3863 pfrec
->status
= CREATE
;
3869 * Now go through and destroy any port forwardings which were
3872 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3873 if (epf
->status
== DESTROY
) {
3876 message
= dupprintf("%s port forwarding from %s%s%d",
3877 epf
->type
== 'L' ?
"local" :
3878 epf
->type
== 'R' ?
"remote" : "dynamic",
3879 epf
->saddr ? epf
->saddr
: "",
3880 epf
->saddr ?
":" : "",
3883 if (epf
->type
!= 'D') {
3884 char *msg2
= dupprintf("%s to %s:%d", message
,
3885 epf
->daddr
, epf
->dport
);
3890 logeventf(ssh
, "Cancelling %s", message
);
3894 struct ssh_rportfwd
*rpf
= epf
->remote
;
3895 struct Packet
*pktout
;
3898 * Cancel the port forwarding at the server
3901 if (ssh
->version
== 1) {
3903 * We cannot cancel listening ports on the
3904 * server side in SSH1! There's no message
3905 * to support it. Instead, we simply remove
3906 * the rportfwd record from the local end
3907 * so that any connections the server tries
3908 * to make on it are rejected.
3911 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
3912 ssh2_pkt_addstring(pktout
, "cancel-tcpip-forward");
3913 ssh2_pkt_addbool(pktout
, 0);/* _don't_ want reply */
3915 ssh2_pkt_addstring(pktout
, epf
->saddr
);
3916 } else if (ssh
->cfg
.rport_acceptall
) {
3917 ssh2_pkt_addstring(pktout
, "0.0.0.0");
3919 ssh2_pkt_addstring(pktout
, "127.0.0.1");
3921 ssh2_pkt_adduint32(pktout
, epf
->sport
);
3922 ssh2_pkt_send(ssh
, pktout
);
3925 del234(ssh
->rportfwds
, rpf
);
3927 } else if (epf
->local
) {
3928 pfd_terminate(epf
->local
);
3931 delpos234(ssh
->portfwds
, i
);
3933 i
--; /* so we don't skip one in the list */
3937 * And finally, set up any new port forwardings (status==CREATE).
3939 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3940 if (epf
->status
== CREATE
) {
3941 char *sportdesc
, *dportdesc
;
3942 sportdesc
= dupprintf("%s%s%s%s%d%s",
3943 epf
->saddr ? epf
->saddr
: "",
3944 epf
->saddr ?
":" : "",
3945 epf
->sserv ? epf
->sserv
: "",
3946 epf
->sserv ?
"(" : "",
3948 epf
->sserv ?
")" : "");
3949 if (epf
->type
== 'D') {
3952 dportdesc
= dupprintf("%s:%s%s%d%s",
3954 epf
->dserv ? epf
->dserv
: "",
3955 epf
->dserv ?
"(" : "",
3957 epf
->dserv ?
")" : "");
3960 if (epf
->type
== 'L') {
3961 const char *err
= pfd_addforward(epf
->daddr
, epf
->dport
,
3962 epf
->saddr
, epf
->sport
,
3965 epf
->addressfamily
);
3967 logeventf(ssh
, "Local %sport %s forwarding to %s%s%s",
3968 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
3969 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
3970 sportdesc
, dportdesc
,
3971 err ?
" failed: " : "", err ? err
: "");
3972 } else if (epf
->type
== 'D') {
3973 const char *err
= pfd_addforward(NULL
, -1,
3974 epf
->saddr
, epf
->sport
,
3977 epf
->addressfamily
);
3979 logeventf(ssh
, "Local %sport %s SOCKS dynamic forwarding%s%s",
3980 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
3981 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
3983 err ?
" failed: " : "", err ? err
: "");
3985 struct ssh_rportfwd
*pf
;
3988 * Ensure the remote port forwardings tree exists.
3990 if (!ssh
->rportfwds
) {
3991 if (ssh
->version
== 1)
3992 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3994 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
3997 pf
= snew(struct ssh_rportfwd
);
3998 strncpy(pf
->dhost
, epf
->daddr
, lenof(pf
->dhost
)-1);
3999 pf
->dhost
[lenof(pf
->dhost
)-1] = '\0';
4000 pf
->dport
= epf
->dport
;
4001 pf
->sport
= epf
->sport
;
4002 if (add234(ssh
->rportfwds
, pf
) != pf
) {
4003 logeventf(ssh
, "Duplicate remote port forwarding to %s:%d",
4004 epf
->daddr
, epf
->dport
);
4007 logeventf(ssh
, "Requesting remote port %s"
4008 " forward to %s", sportdesc
, dportdesc
);
4010 pf
->sportdesc
= sportdesc
;
4015 if (ssh
->version
== 1) {
4016 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
4017 PKT_INT
, epf
->sport
,
4018 PKT_STR
, epf
->daddr
,
4019 PKT_INT
, epf
->dport
,
4021 ssh_queue_handler(ssh
, SSH1_SMSG_SUCCESS
,
4023 ssh_rportfwd_succfail
, pf
);
4025 struct Packet
*pktout
;
4026 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
4027 ssh2_pkt_addstring(pktout
, "tcpip-forward");
4028 ssh2_pkt_addbool(pktout
, 1);/* want reply */
4030 ssh2_pkt_addstring(pktout
, epf
->saddr
);
4031 } else if (ssh
->cfg
.rport_acceptall
) {
4032 ssh2_pkt_addstring(pktout
, "0.0.0.0");
4034 ssh2_pkt_addstring(pktout
, "127.0.0.1");
4036 ssh2_pkt_adduint32(pktout
, epf
->sport
);
4037 ssh2_pkt_send(ssh
, pktout
);
4039 ssh_queue_handler(ssh
, SSH2_MSG_REQUEST_SUCCESS
,
4040 SSH2_MSG_REQUEST_FAILURE
,
4041 ssh_rportfwd_succfail
, pf
);
4050 static void ssh1_smsg_stdout_stderr_data(Ssh ssh
, struct Packet
*pktin
)
4053 int stringlen
, bufsize
;
4055 ssh_pkt_getstring(pktin
, &string
, &stringlen
);
4056 if (string
== NULL
) {
4057 bombout(("Incoming terminal data packet was badly formed"));
4061 bufsize
= from_backend(ssh
->frontend
, pktin
->type
== SSH1_SMSG_STDERR_DATA
,
4063 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4064 ssh
->v1_stdout_throttling
= 1;
4065 ssh1_throttle(ssh
, +1);
4069 static void ssh1_smsg_x11_open(Ssh ssh
, struct Packet
*pktin
)
4071 /* Remote side is trying to open a channel to talk to our
4072 * X-Server. Give them back a local channel number. */
4073 struct ssh_channel
*c
;
4074 int remoteid
= ssh_pkt_getuint32(pktin
);
4076 logevent("Received X11 connect request");
4077 /* Refuse if X11 forwarding is disabled. */
4078 if (!ssh
->X11_fwd_enabled
) {
4079 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4080 PKT_INT
, remoteid
, PKT_END
);
4081 logevent("Rejected X11 connect request");
4083 c
= snew(struct ssh_channel
);
4086 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
4087 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
4088 logevent("Opening X11 forward connection failed");
4090 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4091 PKT_INT
, remoteid
, PKT_END
);
4094 ("Opening X11 forward connection succeeded");
4095 c
->remoteid
= remoteid
;
4096 c
->localid
= alloc_channel_id(ssh
);
4098 c
->v
.v1
.throttling
= 0;
4099 c
->type
= CHAN_X11
; /* identify channel type */
4100 add234(ssh
->channels
, c
);
4101 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4102 PKT_INT
, c
->remoteid
, PKT_INT
,
4103 c
->localid
, PKT_END
);
4104 logevent("Opened X11 forward channel");
4109 static void ssh1_smsg_agent_open(Ssh ssh
, struct Packet
*pktin
)
4111 /* Remote side is trying to open a channel to talk to our
4112 * agent. Give them back a local channel number. */
4113 struct ssh_channel
*c
;
4114 int remoteid
= ssh_pkt_getuint32(pktin
);
4116 /* Refuse if agent forwarding is disabled. */
4117 if (!ssh
->agentfwd_enabled
) {
4118 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4119 PKT_INT
, remoteid
, PKT_END
);
4121 c
= snew(struct ssh_channel
);
4123 c
->remoteid
= remoteid
;
4124 c
->localid
= alloc_channel_id(ssh
);
4126 c
->v
.v1
.throttling
= 0;
4127 c
->type
= CHAN_AGENT
; /* identify channel type */
4128 c
->u
.a
.lensofar
= 0;
4129 add234(ssh
->channels
, c
);
4130 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4131 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
4136 static void ssh1_msg_port_open(Ssh ssh
, struct Packet
*pktin
)
4138 /* Remote side is trying to open a channel to talk to a
4139 * forwarded port. Give them back a local channel number. */
4140 struct ssh_channel
*c
;
4141 struct ssh_rportfwd pf
, *pfp
;
4144 char *host
, buf
[1024];
4146 c
= snew(struct ssh_channel
);
4149 remoteid
= ssh_pkt_getuint32(pktin
);
4150 ssh_pkt_getstring(pktin
, &host
, &hostsize
);
4151 port
= ssh_pkt_getuint32(pktin
);
4153 if (hostsize
>= lenof(pf
.dhost
))
4154 hostsize
= lenof(pf
.dhost
)-1;
4155 memcpy(pf
.dhost
, host
, hostsize
);
4156 pf
.dhost
[hostsize
] = '\0';
4158 pfp
= find234(ssh
->rportfwds
, &pf
, NULL
);
4161 sprintf(buf
, "Rejected remote port open request for %s:%d",
4164 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4165 PKT_INT
, remoteid
, PKT_END
);
4167 sprintf(buf
, "Received remote port open request for %s:%d",
4170 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
4171 c
, &ssh
->cfg
, pfp
->pfrec
->addressfamily
);
4174 sprintf(buf
, "Port open failed: %s", e
);
4177 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4178 PKT_INT
, remoteid
, PKT_END
);
4180 c
->remoteid
= remoteid
;
4181 c
->localid
= alloc_channel_id(ssh
);
4183 c
->v
.v1
.throttling
= 0;
4184 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
4185 add234(ssh
->channels
, c
);
4186 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4187 PKT_INT
, c
->remoteid
, PKT_INT
,
4188 c
->localid
, PKT_END
);
4189 logevent("Forwarded port opened successfully");
4194 static void ssh1_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
4196 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4197 unsigned int localid
= ssh_pkt_getuint32(pktin
);
4198 struct ssh_channel
*c
;
4200 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4201 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4202 c
->remoteid
= localid
;
4203 c
->type
= CHAN_SOCKDATA
;
4204 c
->v
.v1
.throttling
= 0;
4205 pfd_confirm(c
->u
.pfd
.s
);
4208 if (c
&& c
->closes
) {
4210 * We have a pending close on this channel,
4211 * which we decided on before the server acked
4212 * the channel open. So now we know the
4213 * remoteid, we can close it again.
4215 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
4216 PKT_INT
, c
->remoteid
, PKT_END
);
4220 static void ssh1_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
4222 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4223 struct ssh_channel
*c
;
4225 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4226 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4227 logevent("Forwarded connection refused by server");
4228 pfd_close(c
->u
.pfd
.s
);
4229 del234(ssh
->channels
, c
);
4234 static void ssh1_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
4236 /* Remote side closes a channel. */
4237 unsigned i
= ssh_pkt_getuint32(pktin
);
4238 struct ssh_channel
*c
;
4239 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4240 if (c
&& ((int)c
->remoteid
) != -1) {
4243 (pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
4245 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
4246 logevent("Forwarded X11 connection terminated");
4247 assert(c
->u
.x11
.s
!= NULL
);
4248 x11_close(c
->u
.x11
.s
);
4251 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
4252 logevent("Forwarded port closed");
4253 assert(c
->u
.pfd
.s
!= NULL
);
4254 pfd_close(c
->u
.pfd
.s
);
4258 c
->closes
|= (closetype
<< 2); /* seen this message */
4259 if (!(c
->closes
& closetype
)) {
4260 send_packet(ssh
, pktin
->type
, PKT_INT
, c
->remoteid
,
4262 c
->closes
|= closetype
; /* sent it too */
4265 if (c
->closes
== 15) {
4266 del234(ssh
->channels
, c
);
4270 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4271 pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
4272 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
4277 static void ssh1_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
4279 /* Data sent down one of our channels. */
4280 int i
= ssh_pkt_getuint32(pktin
);
4283 struct ssh_channel
*c
;
4285 ssh_pkt_getstring(pktin
, &p
, &len
);
4287 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4292 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
4295 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
4298 /* Data for an agent message. Buffer it. */
4300 if (c
->u
.a
.lensofar
< 4) {
4301 unsigned int l
= min(4 - c
->u
.a
.lensofar
, len
);
4302 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
4306 c
->u
.a
.lensofar
+= l
;
4308 if (c
->u
.a
.lensofar
== 4) {
4310 4 + GET_32BIT(c
->u
.a
.msglen
);
4311 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
4313 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
4315 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
4317 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
4319 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
4323 c
->u
.a
.lensofar
+= l
;
4325 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
4328 if (agent_query(c
->u
.a
.message
,
4331 ssh_agentf_callback
, c
))
4332 ssh_agentf_callback(c
, reply
, replylen
);
4333 sfree(c
->u
.a
.message
);
4334 c
->u
.a
.lensofar
= 0;
4337 bufsize
= 0; /* agent channels never back up */
4340 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4341 c
->v
.v1
.throttling
= 1;
4342 ssh1_throttle(ssh
, +1);
4347 static void ssh1_smsg_exit_status(Ssh ssh
, struct Packet
*pktin
)
4350 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
4351 sprintf(buf
, "Server sent command exit status %d",
4354 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
4356 * In case `helpful' firewalls or proxies tack
4357 * extra human-readable text on the end of the
4358 * session which we might mistake for another
4359 * encrypted packet, we close the session once
4360 * we've sent EXIT_CONFIRMATION.
4362 ssh
->close_expected
= TRUE
;
4363 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4366 static void do_ssh1_connection(Ssh ssh
, unsigned char *in
, int inlen
,
4367 struct Packet
*pktin
)
4369 crBegin(ssh
->do_ssh1_connection_crstate
);
4371 ssh
->packet_dispatch
[SSH1_SMSG_STDOUT_DATA
] =
4372 ssh
->packet_dispatch
[SSH1_SMSG_STDERR_DATA
] =
4373 ssh1_smsg_stdout_stderr_data
;
4375 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
] =
4376 ssh1_msg_channel_open_confirmation
;
4377 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_FAILURE
] =
4378 ssh1_msg_channel_open_failure
;
4379 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE
] =
4380 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
] =
4381 ssh1_msg_channel_close
;
4382 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_DATA
] = ssh1_msg_channel_data
;
4383 ssh
->packet_dispatch
[SSH1_SMSG_EXIT_STATUS
] = ssh1_smsg_exit_status
;
4385 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
4386 logevent("Requesting agent forwarding");
4387 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
4391 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4392 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4393 bombout(("Protocol confusion"));
4395 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4396 logevent("Agent forwarding refused");
4398 logevent("Agent forwarding enabled");
4399 ssh
->agentfwd_enabled
= TRUE
;
4400 ssh
->packet_dispatch
[SSH1_SMSG_AGENT_OPEN
] = ssh1_smsg_agent_open
;
4404 if (ssh
->cfg
.x11_forward
) {
4405 char proto
[20], data
[64];
4406 logevent("Requesting X11 forwarding");
4407 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
4408 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
4409 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
4410 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
4411 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4412 PKT_STR
, proto
, PKT_STR
, data
,
4413 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
4416 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4417 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
4422 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4423 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4424 bombout(("Protocol confusion"));
4426 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4427 logevent("X11 forwarding refused");
4429 logevent("X11 forwarding enabled");
4430 ssh
->X11_fwd_enabled
= TRUE
;
4431 ssh
->packet_dispatch
[SSH1_SMSG_X11_OPEN
] = ssh1_smsg_x11_open
;
4435 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
4436 ssh
->packet_dispatch
[SSH1_MSG_PORT_OPEN
] = ssh1_msg_port_open
;
4438 if (!ssh
->cfg
.nopty
) {
4439 /* Unpick the terminal-speed string. */
4440 /* XXX perhaps we should allow no speeds to be sent. */
4441 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
4442 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
4443 /* Send the pty request. */
4444 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
4445 PKT_STR
, ssh
->cfg
.termtype
,
4446 PKT_INT
, ssh
->term_height
,
4447 PKT_INT
, ssh
->term_width
,
4448 PKT_INT
, 0, PKT_INT
, 0, /* width,height in pixels */
4449 PKT_CHAR
, 192, PKT_INT
, ssh
->ispeed
, /* TTY_OP_ISPEED */
4450 PKT_CHAR
, 193, PKT_INT
, ssh
->ospeed
, /* TTY_OP_OSPEED */
4451 PKT_CHAR
, 0, PKT_END
);
4452 ssh
->state
= SSH_STATE_INTERMED
;
4456 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4457 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4458 bombout(("Protocol confusion"));
4460 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4461 c_write_str(ssh
, "Server refused to allocate pty\r\n");
4462 ssh
->editing
= ssh
->echoing
= 1;
4464 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
4465 ssh
->ospeed
, ssh
->ispeed
);
4467 ssh
->editing
= ssh
->echoing
= 1;
4470 if (ssh
->cfg
.compression
) {
4471 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
4475 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4476 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4477 bombout(("Protocol confusion"));
4479 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4480 c_write_str(ssh
, "Server refused to compress\r\n");
4482 logevent("Started compression");
4483 ssh
->v1_compressing
= TRUE
;
4484 ssh
->cs_comp_ctx
= zlib_compress_init();
4485 logevent("Initialised zlib (RFC1950) compression");
4486 ssh
->sc_comp_ctx
= zlib_decompress_init();
4487 logevent("Initialised zlib (RFC1950) decompression");
4491 * Start the shell or command.
4493 * Special case: if the first-choice command is an SSH2
4494 * subsystem (hence not usable here) and the second choice
4495 * exists, we fall straight back to that.
4498 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
4500 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
4501 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
4502 ssh
->fallback_cmd
= TRUE
;
4505 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
4507 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
4508 logevent("Started session");
4511 ssh
->state
= SSH_STATE_SESSION
;
4512 if (ssh
->size_needed
)
4513 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
4514 if (ssh
->eof_needed
)
4515 ssh_special(ssh
, TS_EOF
);
4518 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
4520 ssh
->channels
= newtree234(ssh_channelcmp
);
4524 * By this point, most incoming packets are already being
4525 * handled by the dispatch table, and we need only pay
4526 * attention to the unusual ones.
4531 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
4532 /* may be from EXEC_SHELL on some servers */
4533 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4534 /* may be from EXEC_SHELL on some servers
4535 * if no pty is available or in other odd cases. Ignore */
4537 bombout(("Strange packet received: type %d", pktin
->type
));
4542 int len
= min(inlen
, 512);
4543 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4544 PKT_INT
, len
, PKT_DATA
, in
, len
,
4545 PKTT_OTHER
, PKT_END
);
4556 * Handle the top-level SSH2 protocol.
4558 static void ssh1_msg_debug(Ssh ssh
, struct Packet
*pktin
)
4563 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4564 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
4569 static void ssh1_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
4571 /* log reason code in disconnect message */
4575 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4576 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen
, msg
));
4579 void ssh_msg_ignore(Ssh ssh
, struct Packet
*pktin
)
4581 /* Do nothing, because we're ignoring it! Duhh. */
4584 static void ssh1_protocol_setup(Ssh ssh
)
4589 * Most messages are handled by the coroutines.
4591 for (i
= 0; i
< 256; i
++)
4592 ssh
->packet_dispatch
[i
] = NULL
;
4595 * These special message types we install handlers for.
4597 ssh
->packet_dispatch
[SSH1_MSG_DISCONNECT
] = ssh1_msg_disconnect
;
4598 ssh
->packet_dispatch
[SSH1_MSG_IGNORE
] = ssh_msg_ignore
;
4599 ssh
->packet_dispatch
[SSH1_MSG_DEBUG
] = ssh1_msg_debug
;
4602 static void ssh1_protocol(Ssh ssh
, void *vin
, int inlen
,
4603 struct Packet
*pktin
)
4605 unsigned char *in
=(unsigned char*)vin
;
4606 if (ssh
->state
== SSH_STATE_CLOSED
)
4609 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
4610 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
4614 if (!ssh
->protocol_initial_phase_done
) {
4615 if (do_ssh1_login(ssh
, in
, inlen
, pktin
))
4616 ssh
->protocol_initial_phase_done
= TRUE
;
4621 do_ssh1_connection(ssh
, in
, inlen
, pktin
);
4625 * Utility routine for decoding comma-separated strings in KEXINIT.
4627 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
4630 if (!needle
|| !haystack
) /* protect against null pointers */
4632 needlen
= strlen(needle
);
4635 * Is it at the start of the string?
4637 if (haylen
>= needlen
&& /* haystack is long enough */
4638 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4639 (haylen
== needlen
|| haystack
[needlen
] == ',')
4640 /* either , or EOS follows */
4644 * If not, search for the next comma and resume after that.
4645 * If no comma found, terminate.
4647 while (haylen
> 0 && *haystack
!= ',')
4648 haylen
--, haystack
++;
4651 haylen
--, haystack
++; /* skip over comma itself */
4656 * SSH2 key creation method.
4658 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
4659 unsigned char *sessid
, char chr
,
4660 unsigned char *keyspace
)
4663 /* First 20 bytes. */
4665 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4667 SHA_Bytes(&s
, H
, 20);
4668 SHA_Bytes(&s
, &chr
, 1);
4669 SHA_Bytes(&s
, sessid
, 20);
4670 SHA_Final(&s
, keyspace
);
4671 /* Next 20 bytes. */
4673 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4675 SHA_Bytes(&s
, H
, 20);
4676 SHA_Bytes(&s
, keyspace
, 20);
4677 SHA_Final(&s
, keyspace
+ 20);
4681 * Handle the SSH2 transport layer.
4683 static int do_ssh2_transport(Ssh ssh
, void *vin
, int inlen
,
4684 struct Packet
*pktin
)
4686 unsigned char *in
= (unsigned char *)vin
;
4687 struct do_ssh2_transport_state
{
4688 int nbits
, pbits
, warn
;
4689 Bignum p
, g
, e
, f
, K
;
4690 int kex_init_value
, kex_reply_value
;
4691 const struct ssh_mac
**maclist
;
4693 const struct ssh2_cipher
*cscipher_tobe
;
4694 const struct ssh2_cipher
*sccipher_tobe
;
4695 const struct ssh_mac
*csmac_tobe
;
4696 const struct ssh_mac
*scmac_tobe
;
4697 const struct ssh_compress
*cscomp_tobe
;
4698 const struct ssh_compress
*sccomp_tobe
;
4699 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4700 int hostkeylen
, siglen
;
4701 void *hkey
; /* actual host key */
4702 unsigned char exchange_hash
[20];
4703 int n_preferred_kex
;
4704 const struct ssh_kex
*preferred_kex
[KEX_MAX
];
4705 int n_preferred_ciphers
;
4706 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
4707 const struct ssh_compress
*preferred_comp
;
4708 int got_session_id
, activated_authconn
;
4709 struct Packet
*pktout
;
4711 crState(do_ssh2_transport_state
);
4713 crBegin(ssh
->do_ssh2_transport_crstate
);
4715 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
4716 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
4717 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
4719 s
->got_session_id
= s
->activated_authconn
= FALSE
;
4722 * Be prepared to work around the buggy MAC problem.
4724 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
4725 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
4727 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
4730 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_KEX_MASK
;
4732 int i
, j
, commalist_started
;
4735 * Set up the preferred key exchange. (NULL => warn below here)
4737 s
->n_preferred_kex
= 0;
4738 for (i
= 0; i
< KEX_MAX
; i
++) {
4739 switch (ssh
->cfg
.ssh_kexlist
[i
]) {
4741 s
->preferred_kex
[s
->n_preferred_kex
++] =
4742 &ssh_diffiehellman_gex
;
4745 s
->preferred_kex
[s
->n_preferred_kex
++] =
4746 &ssh_diffiehellman_group14
;
4749 s
->preferred_kex
[s
->n_preferred_kex
++] =
4750 &ssh_diffiehellman_group1
;
4753 /* Flag for later. Don't bother if it's the last in
4755 if (i
< KEX_MAX
- 1) {
4756 s
->preferred_kex
[s
->n_preferred_kex
++] = NULL
;
4763 * Set up the preferred ciphers. (NULL => warn below here)
4765 s
->n_preferred_ciphers
= 0;
4766 for (i
= 0; i
< CIPHER_MAX
; i
++) {
4767 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
4768 case CIPHER_BLOWFISH
:
4769 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
4772 if (ssh
->cfg
.ssh2_des_cbc
) {
4773 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
4777 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
4780 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
4783 /* Flag for later. Don't bother if it's the last in
4785 if (i
< CIPHER_MAX
- 1) {
4786 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
4793 * Set up preferred compression.
4795 if (ssh
->cfg
.compression
)
4796 s
->preferred_comp
= &ssh_zlib
;
4798 s
->preferred_comp
= &ssh_comp_none
;
4801 * Enable queueing of outgoing auth- or connection-layer
4802 * packets while we are in the middle of a key exchange.
4804 ssh
->queueing
= TRUE
;
4807 * Flag that KEX is in progress.
4809 ssh
->kex_in_progress
= TRUE
;
4812 * Construct and send our key exchange packet.
4814 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEXINIT
);
4815 for (i
= 0; i
< 16; i
++)
4816 ssh2_pkt_addbyte(s
->pktout
, (unsigned char) random_byte());
4817 /* List key exchange algorithms. */
4818 ssh2_pkt_addstring_start(s
->pktout
);
4819 commalist_started
= 0;
4820 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4821 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4822 if (!k
) continue; /* warning flag */
4823 if (commalist_started
)
4824 ssh2_pkt_addstring_str(s
->pktout
, ",");
4825 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_kex
[i
]->name
);
4826 commalist_started
= 1;
4828 /* List server host key algorithms. */
4829 ssh2_pkt_addstring_start(s
->pktout
);
4830 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4831 ssh2_pkt_addstring_str(s
->pktout
, hostkey_algs
[i
]->name
);
4832 if (i
< lenof(hostkey_algs
) - 1)
4833 ssh2_pkt_addstring_str(s
->pktout
, ",");
4835 /* List client->server encryption algorithms. */
4836 ssh2_pkt_addstring_start(s
->pktout
);
4837 commalist_started
= 0;
4838 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4839 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4840 if (!c
) continue; /* warning flag */
4841 for (j
= 0; j
< c
->nciphers
; j
++) {
4842 if (commalist_started
)
4843 ssh2_pkt_addstring_str(s
->pktout
, ",");
4844 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4845 commalist_started
= 1;
4848 /* List server->client encryption algorithms. */
4849 ssh2_pkt_addstring_start(s
->pktout
);
4850 commalist_started
= 0;
4851 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4852 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4853 if (!c
) continue; /* warning flag */
4854 for (j
= 0; j
< c
->nciphers
; j
++) {
4855 if (commalist_started
)
4856 ssh2_pkt_addstring_str(s
->pktout
, ",");
4857 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4858 commalist_started
= 1;
4861 /* List client->server MAC algorithms. */
4862 ssh2_pkt_addstring_start(s
->pktout
);
4863 for (i
= 0; i
< s
->nmacs
; i
++) {
4864 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4865 if (i
< s
->nmacs
- 1)
4866 ssh2_pkt_addstring_str(s
->pktout
, ",");
4868 /* List server->client MAC algorithms. */
4869 ssh2_pkt_addstring_start(s
->pktout
);
4870 for (i
= 0; i
< s
->nmacs
; i
++) {
4871 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4872 if (i
< s
->nmacs
- 1)
4873 ssh2_pkt_addstring_str(s
->pktout
, ",");
4875 /* List client->server compression algorithms. */
4876 ssh2_pkt_addstring_start(s
->pktout
);
4877 assert(lenof(compressions
) > 1);
4878 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4879 for (i
= 0; i
< lenof(compressions
); i
++) {
4880 const struct ssh_compress
*c
= compressions
[i
];
4881 if (c
!= s
->preferred_comp
) {
4882 ssh2_pkt_addstring_str(s
->pktout
, ",");
4883 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4886 /* List server->client compression algorithms. */
4887 ssh2_pkt_addstring_start(s
->pktout
);
4888 assert(lenof(compressions
) > 1);
4889 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4890 for (i
= 0; i
< lenof(compressions
); i
++) {
4891 const struct ssh_compress
*c
= compressions
[i
];
4892 if (c
!= s
->preferred_comp
) {
4893 ssh2_pkt_addstring_str(s
->pktout
, ",");
4894 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4897 /* List client->server languages. Empty list. */
4898 ssh2_pkt_addstring_start(s
->pktout
);
4899 /* List server->client languages. Empty list. */
4900 ssh2_pkt_addstring_start(s
->pktout
);
4901 /* First KEX packet does _not_ follow, because we're not that brave. */
4902 ssh2_pkt_addbool(s
->pktout
, FALSE
);
4904 ssh2_pkt_adduint32(s
->pktout
, 0);
4907 ssh
->exhash
= ssh
->exhashbase
;
4908 sha_string(&ssh
->exhash
, s
->pktout
->data
+ 5, s
->pktout
->length
- 5);
4910 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
4914 if (pktin
->length
> 5)
4915 sha_string(&ssh
->exhash
, pktin
->data
+ 5, pktin
->length
- 5);
4918 * Now examine the other side's KEXINIT to see what we're up
4925 if (pktin
->type
!= SSH2_MSG_KEXINIT
) {
4926 bombout(("expected key exchange packet from server"));
4930 ssh
->hostkey
= NULL
;
4931 s
->cscipher_tobe
= NULL
;
4932 s
->sccipher_tobe
= NULL
;
4933 s
->csmac_tobe
= NULL
;
4934 s
->scmac_tobe
= NULL
;
4935 s
->cscomp_tobe
= NULL
;
4936 s
->sccomp_tobe
= NULL
;
4937 pktin
->savedpos
+= 16; /* skip garbage cookie */
4938 ssh_pkt_getstring(pktin
, &str
, &len
); /* key exchange algorithms */
4940 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4941 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4944 } else if (in_commasep_string(k
->name
, str
, len
)) {
4949 sk_set_frozen(ssh
->s
, 1);
4950 askalg(ssh
->frontend
, "key-exchange algorithm",
4952 sk_set_frozen(ssh
->s
, 0);
4958 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
4959 str ? str
: "(null)"));
4962 ssh_pkt_getstring(pktin
, &str
, &len
); /* host key algorithms */
4963 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4964 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
4965 ssh
->hostkey
= hostkey_algs
[i
];
4969 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server cipher */
4971 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4972 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4976 for (j
= 0; j
< c
->nciphers
; j
++) {
4977 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4978 s
->cscipher_tobe
= c
->list
[j
];
4983 if (s
->cscipher_tobe
) {
4985 sk_set_frozen(ssh
->s
, 1);
4986 askalg(ssh
->frontend
, "client-to-server cipher",
4987 s
->cscipher_tobe
->name
);
4988 sk_set_frozen(ssh
->s
, 0);
4993 if (!s
->cscipher_tobe
) {
4994 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
4995 str ? str
: "(null)"));
4999 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client cipher */
5001 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5002 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5006 for (j
= 0; j
< c
->nciphers
; j
++) {
5007 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
5008 s
->sccipher_tobe
= c
->list
[j
];
5013 if (s
->sccipher_tobe
) {
5015 sk_set_frozen(ssh
->s
, 1);
5016 askalg(ssh
->frontend
, "server-to-client cipher",
5017 s
->sccipher_tobe
->name
);
5018 sk_set_frozen(ssh
->s
, 0);
5023 if (!s
->sccipher_tobe
) {
5024 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
5025 str ? str
: "(null)"));
5029 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server mac */
5030 for (i
= 0; i
< s
->nmacs
; i
++) {
5031 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5032 s
->csmac_tobe
= s
->maclist
[i
];
5036 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client mac */
5037 for (i
= 0; i
< s
->nmacs
; i
++) {
5038 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5039 s
->scmac_tobe
= s
->maclist
[i
];
5043 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server compression */
5044 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5045 const struct ssh_compress
*c
=
5046 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5047 if (in_commasep_string(c
->name
, str
, len
)) {
5052 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client compression */
5053 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5054 const struct ssh_compress
*c
=
5055 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5056 if (in_commasep_string(c
->name
, str
, len
)) {
5064 * Work out the number of bits of key we will need from the key
5065 * exchange. We start with the maximum key length of either
5071 csbits
= s
->cscipher_tobe
->keylen
;
5072 scbits
= s
->sccipher_tobe
->keylen
;
5073 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
5075 /* The keys only have 160-bit entropy, since they're based on
5076 * a SHA-1 hash. So cap the key size at 160 bits. */
5081 * If we're doing Diffie-Hellman group exchange, start by
5082 * requesting a group.
5084 if (!ssh
->kex
->pdata
) {
5085 logevent("Doing Diffie-Hellman group exchange");
5086 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
5088 * Work out how big a DH group we will need to allow that
5091 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
5092 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
5093 ssh2_pkt_adduint32(s
->pktout
, s
->pbits
);
5094 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5097 if (pktin
->type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
5098 bombout(("expected key exchange group packet from server"));
5101 s
->p
= ssh2_pkt_getmp(pktin
);
5102 s
->g
= ssh2_pkt_getmp(pktin
);
5103 if (!s
->p
|| !s
->g
) {
5104 bombout(("unable to read mp-ints from incoming group packet"));
5107 ssh
->kex_ctx
= dh_setup_gex(s
->p
, s
->g
);
5108 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
5109 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
5111 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP
;
5112 ssh
->kex_ctx
= dh_setup_group(ssh
->kex
);
5113 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
5114 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
5115 logeventf(ssh
, "Using Diffie-Hellman with standard group \"%s\"",
5116 ssh
->kex
->groupname
);
5119 logevent("Doing Diffie-Hellman key exchange");
5121 * Now generate and send e for Diffie-Hellman.
5123 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
5124 s
->pktout
= ssh2_pkt_init(s
->kex_init_value
);
5125 ssh2_pkt_addmp(s
->pktout
, s
->e
);
5126 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5129 if (pktin
->type
!= s
->kex_reply_value
) {
5130 bombout(("expected key exchange reply packet from server"));
5133 ssh_pkt_getstring(pktin
, &s
->hostkeydata
, &s
->hostkeylen
);
5134 s
->f
= ssh2_pkt_getmp(pktin
);
5136 bombout(("unable to parse key exchange reply packet"));
5139 ssh_pkt_getstring(pktin
, &s
->sigdata
, &s
->siglen
);
5141 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
5143 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
5144 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5145 sha_uint32(&ssh
->exhash
, s
->pbits
);
5146 sha_mpint(&ssh
->exhash
, s
->p
);
5147 sha_mpint(&ssh
->exhash
, s
->g
);
5149 sha_mpint(&ssh
->exhash
, s
->e
);
5150 sha_mpint(&ssh
->exhash
, s
->f
);
5151 sha_mpint(&ssh
->exhash
, s
->K
);
5152 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
5154 dh_cleanup(ssh
->kex_ctx
);
5155 ssh
->kex_ctx
= NULL
;
5158 debug(("Exchange hash is:\n"));
5159 dmemdump(s
->exchange_hash
, 20);
5162 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
5164 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
5165 (char *)s
->exchange_hash
, 20)) {
5166 bombout(("Server's host key did not match the signature supplied"));
5171 * Authenticate remote host: verify host key. (We've already
5172 * checked the signature of the exchange hash.)
5174 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
5175 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
5176 sk_set_frozen(ssh
->s
, 1);
5177 verify_ssh_host_key(ssh
->frontend
,
5178 ssh
->savedhost
, ssh
->savedport
, ssh
->hostkey
->keytype
,
5179 s
->keystr
, s
->fingerprint
);
5180 sk_set_frozen(ssh
->s
, 0);
5181 if (!s
->got_session_id
) { /* don't bother logging this in rekeys */
5182 logevent("Host key fingerprint is:");
5183 logevent(s
->fingerprint
);
5185 sfree(s
->fingerprint
);
5187 ssh
->hostkey
->freekey(s
->hkey
);
5190 * The exchange hash from the very first key exchange is also
5191 * the session id, used in session key construction and
5194 if (!s
->got_session_id
) {
5195 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
5196 sizeof(s
->exchange_hash
));
5197 s
->got_session_id
= TRUE
;
5201 * Send SSH2_MSG_NEWKEYS.
5203 s
->pktout
= ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
5204 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5205 ssh
->outgoing_data_size
= 0; /* start counting from here */
5208 * We've sent client NEWKEYS, so create and initialise
5209 * client-to-server session keys.
5211 if (ssh
->cs_cipher_ctx
)
5212 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
5213 ssh
->cscipher
= s
->cscipher_tobe
;
5214 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
5216 if (ssh
->cs_mac_ctx
)
5217 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
5218 ssh
->csmac
= s
->csmac_tobe
;
5219 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
5221 if (ssh
->cs_comp_ctx
)
5222 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
5223 ssh
->cscomp
= s
->cscomp_tobe
;
5224 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
5227 * Set IVs on client-to-server keys. Here we use the exchange
5228 * hash from the _first_ key exchange.
5231 unsigned char keyspace
[40];
5232 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
5233 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
5234 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
5235 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
5236 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
5237 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
5240 logeventf(ssh
, "Initialised %.200s client->server encryption",
5241 ssh
->cscipher
->text_name
);
5242 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
5243 ssh
->csmac
->text_name
);
5244 if (ssh
->cscomp
->text_name
)
5245 logeventf(ssh
, "Initialised %s compression",
5246 ssh
->cscomp
->text_name
);
5249 * Now our end of the key exchange is complete, we can send all
5250 * our queued higher-layer packets.
5252 ssh
->queueing
= FALSE
;
5253 ssh2_pkt_queuesend(ssh
);
5256 * Expect SSH2_MSG_NEWKEYS from server.
5259 if (pktin
->type
!= SSH2_MSG_NEWKEYS
) {
5260 bombout(("expected new-keys packet from server"));
5263 ssh
->incoming_data_size
= 0; /* start counting from here */
5266 * We've seen server NEWKEYS, so create and initialise
5267 * server-to-client session keys.
5269 if (ssh
->sc_cipher_ctx
)
5270 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
5271 ssh
->sccipher
= s
->sccipher_tobe
;
5272 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
5274 if (ssh
->sc_mac_ctx
)
5275 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
5276 ssh
->scmac
= s
->scmac_tobe
;
5277 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
5279 if (ssh
->sc_comp_ctx
)
5280 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
5281 ssh
->sccomp
= s
->sccomp_tobe
;
5282 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
5285 * Set IVs on server-to-client keys. Here we use the exchange
5286 * hash from the _first_ key exchange.
5289 unsigned char keyspace
[40];
5290 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
5291 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
5292 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
5293 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
5294 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
5295 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
5297 logeventf(ssh
, "Initialised %.200s server->client encryption",
5298 ssh
->sccipher
->text_name
);
5299 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
5300 ssh
->scmac
->text_name
);
5301 if (ssh
->sccomp
->text_name
)
5302 logeventf(ssh
, "Initialised %s decompression",
5303 ssh
->sccomp
->text_name
);
5306 * Free key exchange data.
5310 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5316 * Key exchange is over. Loop straight back round if we have a
5317 * deferred rekey reason.
5319 if (ssh
->deferred_rekey_reason
) {
5320 logevent(ssh
->deferred_rekey_reason
);
5322 ssh
->deferred_rekey_reason
= NULL
;
5323 goto begin_key_exchange
;
5327 * Otherwise, schedule a timer for our next rekey.
5329 ssh
->kex_in_progress
= FALSE
;
5330 ssh
->last_rekey
= GETTICKCOUNT();
5331 if (ssh
->cfg
.ssh_rekey_time
!= 0)
5332 ssh
->next_rekey
= schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5336 * If this is the first key exchange phase, we must pass the
5337 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5338 * wants to see it but because it will need time to initialise
5339 * itself before it sees an actual packet. In subsequent key
5340 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5341 * it would only confuse the layer above.
5343 if (s
->activated_authconn
) {
5346 s
->activated_authconn
= TRUE
;
5349 * Now we're encrypting. Begin returning 1 to the protocol main
5350 * function so that other things can run on top of the
5351 * transport. If we ever see a KEXINIT, we must go back to the
5354 * We _also_ go back to the start if we see pktin==NULL and
5355 * inlen==-1, because this is a special signal meaning
5356 * `initiate client-driven rekey', and `in' contains a message
5357 * giving the reason for the rekey.
5359 while (!((pktin
&& pktin
->type
== SSH2_MSG_KEXINIT
) ||
5360 (!pktin
&& inlen
== -1))) {
5365 logevent("Server initiated key re-exchange");
5368 * Special case: if the server bug is set that doesn't
5369 * allow rekeying, we give a different log message and
5370 * continue waiting. (If such a server _initiates_ a rekey,
5371 * we process it anyway!)
5373 if ((ssh
->remote_bugs
& BUG_SSH2_REKEY
)) {
5374 logeventf(ssh
, "Server bug prevents key re-exchange (%s)",
5376 /* Reset the counters, so that at least this message doesn't
5377 * hit the event log _too_ often. */
5378 ssh
->outgoing_data_size
= 0;
5379 ssh
->incoming_data_size
= 0;
5380 if (ssh
->cfg
.ssh_rekey_time
!= 0) {
5382 schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5385 goto wait_for_rekey
; /* this is utterly horrid */
5387 logeventf(ssh
, "Initiating key re-exchange (%s)", (char *)in
);
5390 goto begin_key_exchange
;
5396 * Add data to an SSH2 channel output buffer.
5398 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
5401 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
5405 * Attempt to send data on an SSH2 channel.
5407 static int ssh2_try_send(struct ssh_channel
*c
)
5410 struct Packet
*pktout
;
5412 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
5415 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
5416 if ((unsigned)len
> c
->v
.v2
.remwindow
)
5417 len
= c
->v
.v2
.remwindow
;
5418 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
5419 len
= c
->v
.v2
.remmaxpkt
;
5420 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
5421 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5422 dont_log_data(ssh
, pktout
, PKTLOG_OMIT
);
5423 ssh2_pkt_addstring_start(pktout
);
5424 ssh2_pkt_addstring_data(pktout
, data
, len
);
5425 end_log_omission(ssh
, pktout
);
5426 ssh2_pkt_send(ssh
, pktout
);
5427 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
5428 c
->v
.v2
.remwindow
-= len
;
5432 * After having sent as much data as we can, return the amount
5435 return bufchain_size(&c
->v
.v2
.outbuffer
);
5439 * Potentially enlarge the window on an SSH2 channel.
5441 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
5446 * Never send WINDOW_ADJUST for a channel that the remote side
5447 * already thinks it's closed; there's no point, since it won't
5448 * be sending any more data anyway.
5454 * Only send a WINDOW_ADJUST if there's significantly more window
5455 * available than the other end thinks there is. This saves us
5456 * sending a WINDOW_ADJUST for every character in a shell session.
5458 * "Significant" is arbitrarily defined as half the window size.
5460 if (newwin
> c
->v
.v2
.locwindow
* 2) {
5461 struct Packet
*pktout
;
5463 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5464 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5465 ssh2_pkt_adduint32(pktout
, newwin
- c
->v
.v2
.locwindow
);
5466 ssh2_pkt_send(ssh
, pktout
);
5467 c
->v
.v2
.locwindow
= newwin
;
5471 static void ssh2_msg_channel_window_adjust(Ssh ssh
, struct Packet
*pktin
)
5473 unsigned i
= ssh_pkt_getuint32(pktin
);
5474 struct ssh_channel
*c
;
5475 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5476 if (c
&& !c
->closes
)
5477 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
5480 static void ssh2_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
5484 unsigned i
= ssh_pkt_getuint32(pktin
);
5485 struct ssh_channel
*c
;
5486 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5488 return; /* nonexistent channel */
5489 if (pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5490 ssh_pkt_getuint32(pktin
) != SSH2_EXTENDED_DATA_STDERR
)
5491 return; /* extended but not stderr */
5492 ssh_pkt_getstring(pktin
, &data
, &length
);
5495 c
->v
.v2
.locwindow
-= length
;
5497 case CHAN_MAINSESSION
:
5499 from_backend(ssh
->frontend
, pktin
->type
==
5500 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5504 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5507 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5510 while (length
> 0) {
5511 if (c
->u
.a
.lensofar
< 4) {
5512 unsigned int l
= min(4 - c
->u
.a
.lensofar
, length
);
5513 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5517 c
->u
.a
.lensofar
+= l
;
5519 if (c
->u
.a
.lensofar
== 4) {
5521 4 + GET_32BIT(c
->u
.a
.msglen
);
5522 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
5524 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5526 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5528 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5530 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5534 c
->u
.a
.lensofar
+= l
;
5536 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5539 if (agent_query(c
->u
.a
.message
,
5542 ssh_agentf_callback
, c
))
5543 ssh_agentf_callback(c
, reply
, replylen
);
5544 sfree(c
->u
.a
.message
);
5545 c
->u
.a
.lensofar
= 0;
5552 * If we are not buffering too much data,
5553 * enlarge the window again at the remote side.
5555 if (bufsize
< OUR_V2_WINSIZE
)
5556 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5560 static void ssh2_msg_channel_eof(Ssh ssh
, struct Packet
*pktin
)
5562 unsigned i
= ssh_pkt_getuint32(pktin
);
5563 struct ssh_channel
*c
;
5565 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5567 return; /* nonexistent channel */
5569 if (c
->type
== CHAN_X11
) {
5571 * Remote EOF on an X11 channel means we should
5572 * wrap up and close the channel ourselves.
5574 x11_close(c
->u
.x11
.s
);
5576 } else if (c
->type
== CHAN_AGENT
) {
5578 } else if (c
->type
== CHAN_SOCKDATA
) {
5579 pfd_close(c
->u
.pfd
.s
);
5584 static void ssh2_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
5586 unsigned i
= ssh_pkt_getuint32(pktin
);
5587 struct ssh_channel
*c
;
5588 struct Packet
*pktout
;
5590 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5591 if (!c
|| ((int)c
->remoteid
) == -1) {
5592 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5593 c ?
"half-open" : "nonexistent", i
));
5596 /* Do pre-close processing on the channel. */
5598 case CHAN_MAINSESSION
:
5599 ssh
->mainchan
= NULL
;
5600 update_specials_menu(ssh
->frontend
);
5603 if (c
->u
.x11
.s
!= NULL
)
5604 x11_close(c
->u
.x11
.s
);
5611 if (c
->u
.pfd
.s
!= NULL
)
5612 pfd_close(c
->u
.pfd
.s
);
5616 if (c
->closes
== 0) {
5617 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5618 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5619 ssh2_pkt_send(ssh
, pktout
);
5621 del234(ssh
->channels
, c
);
5622 bufchain_clear(&c
->v
.v2
.outbuffer
);
5626 * See if that was the last channel left open.
5627 * (This is only our termination condition if we're
5628 * not running in -N mode.)
5630 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
5631 logevent("All channels closed. Disconnecting");
5634 * We used to send SSH_MSG_DISCONNECT here,
5635 * because I'd believed that _every_ conforming
5636 * SSH2 connection had to end with a disconnect
5637 * being sent by at least one side; apparently
5638 * I was wrong and it's perfectly OK to
5639 * unceremoniously slam the connection shut
5640 * when you're done, and indeed OpenSSH feels
5641 * this is more polite than sending a
5642 * DISCONNECT. So now we don't.
5644 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5645 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5646 ssh2_pkt_addstring(s
->pktout
, "All open channels closed");
5647 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
5648 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5650 ssh
->close_expected
= TRUE
;
5651 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5655 static void ssh2_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
5657 unsigned i
= ssh_pkt_getuint32(pktin
);
5658 struct ssh_channel
*c
;
5659 struct Packet
*pktout
;
5661 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5663 return; /* nonexistent channel */
5664 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5665 return; /* dunno why they're confirming this */
5666 c
->remoteid
= ssh_pkt_getuint32(pktin
);
5667 c
->type
= CHAN_SOCKDATA
;
5668 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
5669 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
5671 pfd_confirm(c
->u
.pfd
.s
);
5674 * We have a pending close on this channel,
5675 * which we decided on before the server acked
5676 * the channel open. So now we know the
5677 * remoteid, we can close it again.
5679 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5680 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5681 ssh2_pkt_send(ssh
, pktout
);
5685 static void ssh2_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
5687 static const char *const reasons
[] = {
5688 "<unknown reason code>",
5689 "Administratively prohibited",
5691 "Unknown channel type",
5692 "Resource shortage",
5694 unsigned i
= ssh_pkt_getuint32(pktin
);
5695 unsigned reason_code
;
5696 char *reason_string
;
5699 struct ssh_channel
*c
;
5700 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5702 return; /* nonexistent channel */
5703 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5704 return; /* dunno why they're failing this */
5706 reason_code
= ssh_pkt_getuint32(pktin
);
5707 if (reason_code
>= lenof(reasons
))
5708 reason_code
= 0; /* ensure reasons[reason_code] in range */
5709 ssh_pkt_getstring(pktin
, &reason_string
, &reason_length
);
5710 message
= dupprintf("Forwarded connection refused by"
5711 " server: %s [%.*s]", reasons
[reason_code
],
5712 reason_length
, reason_string
);
5716 pfd_close(c
->u
.pfd
.s
);
5718 del234(ssh
->channels
, c
);
5722 static void ssh2_msg_channel_request(Ssh ssh
, struct Packet
*pktin
)
5726 int typelen
, want_reply
;
5727 int reply
= SSH2_MSG_CHANNEL_FAILURE
; /* default */
5728 struct ssh_channel
*c
;
5729 struct Packet
*pktout
;
5731 localid
= ssh_pkt_getuint32(pktin
);
5732 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5733 want_reply
= ssh2_pkt_getbool(pktin
);
5736 * First, check that the channel exists. Otherwise,
5737 * we can instantly disconnect with a rude message.
5739 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
5742 sprintf(buf
, "Received channel request for nonexistent"
5743 " channel %d", localid
);
5745 pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5746 ssh2_pkt_adduint32(pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5747 ssh2_pkt_addstring(pktout
, buf
);
5748 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5749 ssh2_pkt_send_noqueue(ssh
, pktout
);
5750 connection_fatal(ssh
->frontend
, "%s", buf
);
5751 ssh
->close_expected
= TRUE
;
5752 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5757 * Having got the channel number, we now look at
5758 * the request type string to see if it's something
5761 if (c
== ssh
->mainchan
) {
5763 * We recognise "exit-status" and "exit-signal" on
5764 * the primary channel.
5766 if (typelen
== 11 &&
5767 !memcmp(type
, "exit-status", 11)) {
5769 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
5770 logeventf(ssh
, "Server sent command exit status %d",
5772 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5774 } else if (typelen
== 11 &&
5775 !memcmp(type
, "exit-signal", 11)) {
5777 int is_plausible
= TRUE
, is_int
= FALSE
;
5778 char *fmt_sig
= "", *fmt_msg
= "";
5780 int msglen
= 0, core
= FALSE
;
5781 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
5782 * provide an `int' for the signal, despite its
5783 * having been a `string' in the drafts since at
5784 * least 2001. (Fixed in session.c 1.147.) Try to
5785 * infer which we can safely parse it as. */
5787 unsigned char *p
= pktin
->body
+
5789 long len
= pktin
->length
- pktin
->savedpos
;
5790 unsigned long num
= GET_32BIT(p
); /* what is it? */
5791 /* If it's 0, it hardly matters; assume string */
5795 int maybe_int
= FALSE
, maybe_str
= FALSE
;
5796 #define CHECK_HYPOTHESIS(offset, result) \
5799 if (q >= 0 && q+4 <= len) { \
5800 q = q + 4 + GET_32BIT(p+q); \
5801 if (q >= 0 && q+4 <= len && \
5802 ((q = q + 4 + GET_32BIT(p+q))!= 0) && q == len) \
5806 CHECK_HYPOTHESIS(4+1, maybe_int
);
5807 CHECK_HYPOTHESIS(4+num
+1, maybe_str
);
5808 #undef CHECK_HYPOTHESIS
5809 if (maybe_int
&& !maybe_str
)
5811 else if (!maybe_int
&& maybe_str
)
5814 /* Crikey. Either or neither. Panic. */
5815 is_plausible
= FALSE
;
5820 /* Old non-standard OpenSSH. */
5821 int signum
= ssh_pkt_getuint32(pktin
);
5822 fmt_sig
= dupprintf(" %d", signum
);
5824 /* As per the drafts. */
5827 ssh_pkt_getstring(pktin
, &sig
, &siglen
);
5828 /* Signal name isn't supposed to be blank, but
5829 * let's cope gracefully if it is. */
5831 fmt_sig
= dupprintf(" \"%.*s\"",
5835 core
= ssh2_pkt_getbool(pktin
);
5836 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
5838 fmt_msg
= dupprintf(" (\"%.*s\")", msglen
, msg
);
5840 /* ignore lang tag */
5841 } /* else don't attempt to parse */
5842 logeventf(ssh
, "Server exited on signal%s%s%s",
5843 fmt_sig
, core ?
" (core dumped)" : "",
5845 if (*fmt_sig
) sfree(fmt_sig
);
5846 if (*fmt_msg
) sfree(fmt_msg
);
5847 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5852 * This is a channel request we don't know
5853 * about, so we now either ignore the request
5854 * or respond with CHANNEL_FAILURE, depending
5857 reply
= SSH2_MSG_CHANNEL_FAILURE
;
5860 pktout
= ssh2_pkt_init(reply
);
5861 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5862 ssh2_pkt_send(ssh
, pktout
);
5866 static void ssh2_msg_global_request(Ssh ssh
, struct Packet
*pktin
)
5869 int typelen
, want_reply
;
5870 struct Packet
*pktout
;
5872 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5873 want_reply
= ssh2_pkt_getbool(pktin
);
5876 * We currently don't support any global requests
5877 * at all, so we either ignore the request or
5878 * respond with REQUEST_FAILURE, depending on
5882 pktout
= ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
5883 ssh2_pkt_send(ssh
, pktout
);
5887 static void ssh2_msg_channel_open(Ssh ssh
, struct Packet
*pktin
)
5895 struct ssh_channel
*c
;
5896 unsigned remid
, winsize
, pktsize
;
5897 struct Packet
*pktout
;
5899 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5900 c
= snew(struct ssh_channel
);
5903 remid
= ssh_pkt_getuint32(pktin
);
5904 winsize
= ssh_pkt_getuint32(pktin
);
5905 pktsize
= ssh_pkt_getuint32(pktin
);
5907 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5910 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5911 addrstr
= snewn(peeraddrlen
+1, char);
5912 memcpy(addrstr
, peeraddr
, peeraddrlen
);
5913 addrstr
[peeraddrlen
] = '\0';
5914 peerport
= ssh_pkt_getuint32(pktin
);
5916 logeventf(ssh
, "Received X11 connect request from %s:%d",
5919 if (!ssh
->X11_fwd_enabled
)
5920 error
= "X11 forwarding is not enabled";
5921 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
5922 ssh
->x11auth
, addrstr
, peerport
,
5923 &ssh
->cfg
) != NULL
) {
5924 error
= "Unable to open an X11 connection";
5926 logevent("Opening X11 forward connection succeeded");
5931 } else if (typelen
== 15 &&
5932 !memcmp(type
, "forwarded-tcpip", 15)) {
5933 struct ssh_rportfwd pf
, *realpf
;
5936 ssh_pkt_getstring(pktin
, &dummy
, &dummylen
);/* skip address */
5937 pf
.sport
= ssh_pkt_getuint32(pktin
);
5938 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5939 peerport
= ssh_pkt_getuint32(pktin
);
5940 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
5941 logeventf(ssh
, "Received remote port %d open request "
5942 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
5943 if (realpf
== NULL
) {
5944 error
= "Remote port is not recognised";
5946 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
5950 realpf
->pfrec
->addressfamily
);
5951 logeventf(ssh
, "Attempting to forward remote port to "
5952 "%s:%d", realpf
->dhost
, realpf
->dport
);
5954 logeventf(ssh
, "Port open failed: %s", e
);
5955 error
= "Port open failed";
5957 logevent("Forwarded port opened successfully");
5958 c
->type
= CHAN_SOCKDATA
;
5961 } else if (typelen
== 22 &&
5962 !memcmp(type
, "auth-agent@openssh.com", 3)) {
5963 if (!ssh
->agentfwd_enabled
)
5964 error
= "Agent forwarding is not enabled";
5966 c
->type
= CHAN_AGENT
; /* identify channel type */
5967 c
->u
.a
.lensofar
= 0;
5970 error
= "Unsupported channel type requested";
5973 c
->remoteid
= remid
;
5975 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
5976 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5977 ssh2_pkt_adduint32(pktout
, SSH2_OPEN_CONNECT_FAILED
);
5978 ssh2_pkt_addstring(pktout
, error
);
5979 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5980 ssh2_pkt_send(ssh
, pktout
);
5981 logeventf(ssh
, "Rejected channel open: %s", error
);
5984 c
->localid
= alloc_channel_id(ssh
);
5986 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5987 c
->v
.v2
.remwindow
= winsize
;
5988 c
->v
.v2
.remmaxpkt
= pktsize
;
5989 bufchain_init(&c
->v
.v2
.outbuffer
);
5990 add234(ssh
->channels
, c
);
5991 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
5992 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5993 ssh2_pkt_adduint32(pktout
, c
->localid
);
5994 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);
5995 ssh2_pkt_adduint32(pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
5996 ssh2_pkt_send(ssh
, pktout
);
6001 * Handle the SSH2 userauth and connection layers.
6003 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
6004 struct Packet
*pktin
)
6006 struct do_ssh2_authconn_state
{
6008 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
6010 AUTH_KEYBOARD_INTERACTIVE
6014 AUTH_TYPE_PUBLICKEY
,
6015 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
6016 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
6018 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
6019 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
6021 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
6022 int tried_pubkey_config
, tried_agent
;
6023 int kbd_inter_running
, kbd_inter_refused
;
6025 int num_prompts
, curr_prompt
, echo
;
6030 void *publickey_blob
;
6031 int publickey_bloblen
;
6032 unsigned char request
[5], *response
, *p
;
6036 char *pkblob
, *alg
, *commentp
;
6037 int pklen
, alglen
, commentlen
;
6038 int siglen
, retlen
, len
;
6039 char *q
, *agentreq
, *ret
;
6041 int num_env
, env_left
, env_ok
;
6042 struct Packet
*pktout
;
6044 crState(do_ssh2_authconn_state
);
6046 crBegin(ssh
->do_ssh2_authconn_crstate
);
6049 * Request userauth protocol, and await a response to it.
6051 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
6052 ssh2_pkt_addstring(s
->pktout
, "ssh-userauth");
6053 ssh2_pkt_send(ssh
, s
->pktout
);
6054 crWaitUntilV(pktin
);
6055 if (pktin
->type
!= SSH2_MSG_SERVICE_ACCEPT
) {
6056 bombout(("Server refused user authentication protocol"));
6061 * We repeat this whole loop, including the username prompt,
6062 * until we manage a successful authentication. If the user
6063 * types the wrong _password_, they can be sent back to the
6064 * beginning to try another username, if this is configured on.
6065 * (If they specify a username in the config, they are never
6066 * asked, even if they do give a wrong password.)
6068 * I think this best serves the needs of
6070 * - the people who have no configuration, no keys, and just
6071 * want to try repeated (username,password) pairs until they
6072 * type both correctly
6074 * - people who have keys and configuration but occasionally
6075 * need to fall back to passwords
6077 * - people with a key held in Pageant, who might not have
6078 * logged in to a particular machine before; so they want to
6079 * type a username, and then _either_ their key will be
6080 * accepted, _or_ they will type a password. If they mistype
6081 * the username they will want to be able to get back and
6084 s
->username
[0] = '\0';
6085 s
->got_username
= FALSE
;
6090 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
6092 * We got a username last time round this loop, and
6093 * with change_username turned off we don't try to get
6096 } else if (!*ssh
->cfg
.username
) {
6097 if (ssh_get_line
&& !ssh_getline_pw_only
) {
6098 if (!ssh_get_line("login as: ",
6099 s
->username
, sizeof(s
->username
), FALSE
)) {
6101 * get_line failed to get a username.
6104 logevent("No username provided. Abandoning session.");
6105 ssh
->close_expected
= TRUE
;
6106 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6110 int ret
; /* need not be saved across crReturn */
6111 c_write_str(ssh
, "login as: ");
6113 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
6115 crWaitUntilV(!pktin
);
6116 ret
= process_userpass_input(ssh
, in
, inlen
);
6120 c_write_str(ssh
, "\r\n");
6122 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
6125 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
6126 s
->username
[sizeof(s
->username
)-1] = '\0';
6127 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
6128 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
6129 c_write_str(ssh
, stuff
);
6133 s
->got_username
= TRUE
;
6136 * Send an authentication request using method "none": (a)
6137 * just in case it succeeds, and (b) so that we know what
6138 * authentication methods we can usefully try next.
6140 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6142 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6143 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6144 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");/* service requested */
6145 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6146 ssh2_pkt_send(ssh
, s
->pktout
);
6147 s
->type
= AUTH_TYPE_NONE
;
6149 s
->we_are_in
= FALSE
;
6151 s
->tried_pubkey_config
= FALSE
;
6152 s
->tried_agent
= FALSE
;
6153 s
->kbd_inter_running
= FALSE
;
6154 s
->kbd_inter_refused
= FALSE
;
6155 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
6156 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
6158 logeventf(ssh
, "Reading private key file \"%.150s\"",
6159 filename_to_str(&ssh
->cfg
.keyfile
));
6160 keytype
= key_type(&ssh
->cfg
.keyfile
);
6161 if (keytype
== SSH_KEYTYPE_SSH2
) {
6163 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
6164 &s
->publickey_bloblen
, NULL
);
6167 logeventf(ssh
, "Unable to use this key file (%s)",
6168 key_type_to_str(keytype
));
6169 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
6171 filename_to_str(&ssh
->cfg
.keyfile
),
6172 key_type_to_str(keytype
));
6173 c_write_str(ssh
, msgbuf
);
6175 s
->publickey_blob
= NULL
;
6178 s
->publickey_blob
= NULL
;
6182 * Wait for the result of the last authentication request.
6185 crWaitUntilV(pktin
);
6186 while (pktin
->type
== SSH2_MSG_USERAUTH_BANNER
) {
6190 * Don't show the banner if we're operating in
6191 * non-verbose non-interactive mode. (It's probably
6192 * a script, which means nobody will read the
6193 * banner _anyway_, and moreover the printing of
6194 * the banner will screw up processing on the
6195 * output of (say) plink.)
6197 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
6198 ssh_pkt_getstring(pktin
, &banner
, &size
);
6200 c_write_untrusted(ssh
, banner
, size
);
6202 crWaitUntilV(pktin
);
6204 if (pktin
->type
== SSH2_MSG_USERAUTH_SUCCESS
) {
6205 logevent("Access granted");
6206 s
->we_are_in
= TRUE
;
6210 if (s
->kbd_inter_running
&&
6211 pktin
->type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6213 * This is either a further set-of-prompts packet
6214 * in keyboard-interactive authentication, or it's
6215 * the same one and we came back here with `gotit'
6216 * set. In the former case, we must reset the
6217 * curr_prompt variable.
6221 } else if (pktin
->type
== SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
) {
6222 /* FIXME: perhaps we should support this? */
6223 bombout(("PASSWD_CHANGEREQ not yet supported"));
6225 } else if (pktin
->type
!= SSH2_MSG_USERAUTH_FAILURE
) {
6226 bombout(("Strange packet received during authentication: type %d",
6234 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6235 * we can look at the string in it and know what we can
6236 * helpfully try next.
6238 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
) {
6241 ssh_pkt_getstring(pktin
, &methods
, &methlen
);
6242 s
->kbd_inter_running
= FALSE
;
6243 if (!ssh2_pkt_getbool(pktin
)) {
6245 * We have received an unequivocal Access
6246 * Denied. This can translate to a variety of
6249 * - if we'd just tried "none" authentication,
6250 * it's not worth printing anything at all
6252 * - if we'd just tried a public key _offer_,
6253 * the message should be "Server refused our
6254 * key" (or no message at all if the key
6255 * came from Pageant)
6257 * - if we'd just tried anything else, the
6258 * message really should be "Access denied".
6260 * Additionally, if we'd just tried password
6261 * authentication, we should break out of this
6262 * whole loop so as to go back to the username
6263 * prompt (iff we're configured to allow
6264 * username change attempts).
6266 if (s
->type
== AUTH_TYPE_NONE
) {
6268 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
6269 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
6270 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
6271 c_write_str(ssh
, "Server refused our key\r\n");
6272 logevent("Server refused public key");
6273 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
6274 /* server declined keyboard-interactive; ignore */
6276 c_write_str(ssh
, "Access denied\r\n");
6277 logevent("Access denied");
6278 if (s
->type
== AUTH_TYPE_PASSWORD
&&
6279 ssh
->cfg
.change_username
) {
6280 /* XXX perhaps we should allow
6281 * keyboard-interactive to do this too? */
6282 s
->we_are_in
= FALSE
;
6287 c_write_str(ssh
, "Further authentication required\r\n");
6288 logevent("Further authentication required");
6292 in_commasep_string("publickey", methods
, methlen
);
6294 in_commasep_string("password", methods
, methlen
);
6295 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
6296 in_commasep_string("keyboard-interactive", methods
, methlen
);
6300 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6304 * Most password/passphrase prompts will be
6305 * non-echoing, so we set this to 0 by default.
6306 * Exception is that some keyboard-interactive prompts
6307 * can be echoing, in which case we'll set this to 1.
6311 if (!s
->method
&& s
->can_pubkey
&&
6312 agent_exists() && !s
->tried_agent
) {
6314 * Attempt public-key authentication using Pageant.
6319 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6320 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6322 s
->tried_agent
= TRUE
;
6324 logevent("Pageant is running. Requesting keys.");
6326 /* Request the keys held by the agent. */
6327 PUT_32BIT(s
->request
, 1);
6328 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
6329 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
6330 ssh_agent_callback
, ssh
)) {
6334 bombout(("Unexpected data from server while"
6335 " waiting for agent response"));
6338 } while (pktin
|| inlen
> 0);
6339 r
= ssh
->agent_response
;
6340 s
->responselen
= ssh
->agent_response_len
;
6342 s
->response
= (unsigned char *) r
;
6343 if (s
->response
&& s
->responselen
>= 5 &&
6344 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
6345 s
->p
= s
->response
+ 5;
6346 s
->nkeys
= GET_32BIT(s
->p
);
6350 sprintf(buf
, "Pageant has %d SSH2 keys", s
->nkeys
);
6353 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
6358 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
6361 s
->pklen
= GET_32BIT(s
->p
);
6363 if (s
->publickey_blob
&&
6364 s
->pklen
== s
->publickey_bloblen
&&
6365 !memcmp(s
->p
, s
->publickey_blob
,
6366 s
->publickey_bloblen
)) {
6367 logevent("This key matches configured key file");
6368 s
->tried_pubkey_config
= 1;
6370 s
->pkblob
= (char *)s
->p
;
6372 s
->alglen
= GET_32BIT(s
->pkblob
);
6373 s
->alg
= s
->pkblob
+ 4;
6374 s
->commentlen
= GET_32BIT(s
->p
);
6376 s
->commentp
= (char *)s
->p
;
6377 s
->p
+= s
->commentlen
;
6378 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6379 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6380 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6381 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6382 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6383 ssh2_pkt_addstring_start(s
->pktout
);
6384 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6385 ssh2_pkt_addstring_start(s
->pktout
);
6386 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6387 ssh2_pkt_send(ssh
, s
->pktout
);
6389 crWaitUntilV(pktin
);
6390 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6391 logevent("Key refused");
6395 if (flags
& FLAG_VERBOSE
) {
6396 c_write_str(ssh
, "Authenticating with "
6398 c_write(ssh
, s
->commentp
, s
->commentlen
);
6399 c_write_str(ssh
, "\" from agent\r\n");
6403 * Server is willing to accept the key.
6404 * Construct a SIGN_REQUEST.
6406 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6407 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6408 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6409 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6410 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6411 ssh2_pkt_addstring_start(s
->pktout
);
6412 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6413 ssh2_pkt_addstring_start(s
->pktout
);
6414 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6416 s
->siglen
= s
->pktout
->length
- 5 + 4 + 20;
6417 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6419 s
->len
= 1; /* message type */
6420 s
->len
+= 4 + s
->pklen
; /* key blob */
6421 s
->len
+= 4 + s
->siglen
; /* data to sign */
6422 s
->len
+= 4; /* flags */
6423 s
->agentreq
= snewn(4 + s
->len
, char);
6424 PUT_32BIT(s
->agentreq
, s
->len
);
6425 s
->q
= s
->agentreq
+ 4;
6426 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
6427 PUT_32BIT(s
->q
, s
->pklen
);
6429 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
6431 PUT_32BIT(s
->q
, s
->siglen
);
6433 /* Now the data to be signed... */
6434 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6435 PUT_32BIT(s
->q
, 20);
6438 memcpy(s
->q
, ssh
->v2_session_id
, 20);
6440 memcpy(s
->q
, s
->pktout
->data
+ 5,
6441 s
->pktout
->length
- 5);
6442 s
->q
+= s
->pktout
->length
- 5;
6443 /* And finally the (zero) flags word. */
6445 if (!agent_query(s
->agentreq
, s
->len
+ 4,
6447 ssh_agent_callback
, ssh
)) {
6451 bombout(("Unexpected data from server"
6452 " while waiting for agent"
6456 } while (pktin
|| inlen
> 0);
6457 vret
= ssh
->agent_response
;
6458 s
->retlen
= ssh
->agent_response_len
;
6463 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
6464 logevent("Sending Pageant's response");
6465 ssh2_add_sigblob(ssh
, s
->pktout
,
6466 s
->pkblob
, s
->pklen
,
6468 GET_32BIT(s
->ret
+ 5));
6469 ssh2_pkt_send(ssh
, s
->pktout
);
6474 ("Pageant failed to answer challenge");
6485 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
6486 && !s
->tried_pubkey_config
) {
6487 unsigned char *pub_blob
;
6488 char *algorithm
, *comment
;
6491 s
->tried_pubkey_config
= TRUE
;
6493 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6494 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6497 * Try the public key supplied in the configuration.
6499 * First, offer the public blob to see if the server is
6500 * willing to accept it.
6503 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
6508 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6509 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6510 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6511 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6512 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6513 ssh2_pkt_addstring(s
->pktout
, algorithm
);
6514 ssh2_pkt_addstring_start(s
->pktout
);
6515 ssh2_pkt_addstring_data(s
->pktout
, (char *)pub_blob
,
6517 ssh2_pkt_send(ssh
, s
->pktout
);
6518 logevent("Offered public key");
6520 crWaitUntilV(pktin
);
6521 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6523 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
6524 continue; /* key refused; give up on it */
6527 logevent("Offer of public key accepted");
6529 * Actually attempt a serious authentication using
6532 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
6533 sprintf(s
->pwprompt
,
6534 "Passphrase for key \"%.100s\": ",
6540 if (flags
& FLAG_VERBOSE
) {
6541 c_write_str(ssh
, "Authenticating with public key \"");
6542 c_write_str(ssh
, comment
);
6543 c_write_str(ssh
, "\"\r\n");
6545 s
->method
= AUTH_PUBLICKEY_FILE
;
6549 if (!s
->method
&& s
->can_keyb_inter
&& !s
->kbd_inter_refused
&&
6550 !s
->kbd_inter_running
) {
6551 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6552 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6554 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6555 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6557 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6558 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6559 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6560 ssh2_pkt_addstring(s
->pktout
, "keyboard-interactive"); /* method */
6561 ssh2_pkt_addstring(s
->pktout
, ""); /* lang */
6562 ssh2_pkt_addstring(s
->pktout
, "");
6563 ssh2_pkt_send(ssh
, s
->pktout
);
6565 crWaitUntilV(pktin
);
6566 if (pktin
->type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6567 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
)
6569 logevent("Keyboard-interactive authentication refused");
6570 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
6571 s
->kbd_inter_refused
= TRUE
; /* don't try it again */
6575 s
->kbd_inter_running
= TRUE
;
6579 if (s
->kbd_inter_running
) {
6580 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6581 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6583 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6584 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6586 if (s
->curr_prompt
== 0) {
6588 * We've got a fresh USERAUTH_INFO_REQUEST.
6589 * Display header data, and start going through
6592 char *name
, *inst
, *lang
;
6593 int name_len
, inst_len
, lang_len
;
6595 ssh_pkt_getstring(pktin
, &name
, &name_len
);
6596 ssh_pkt_getstring(pktin
, &inst
, &inst_len
);
6597 ssh_pkt_getstring(pktin
, &lang
, &lang_len
);
6599 c_write_untrusted(ssh
, name
, name_len
);
6600 c_write_str(ssh
, "\r\n");
6603 c_write_untrusted(ssh
, inst
, inst_len
);
6604 c_write_str(ssh
, "\r\n");
6606 s
->num_prompts
= ssh_pkt_getuint32(pktin
);
6610 * If there are prompts remaining in the packet,
6611 * display one and get a response.
6613 if (s
->curr_prompt
< s
->num_prompts
) {
6617 ssh_pkt_getstring(pktin
, &prompt
, &prompt_len
);
6618 if (prompt_len
> 0) {
6619 static const char trunc
[] = "<prompt truncated>: ";
6620 static const int prlen
= sizeof(s
->pwprompt
) -
6622 if (prompt_len
> prlen
) {
6623 memcpy(s
->pwprompt
, prompt
, prlen
);
6624 strcpy(s
->pwprompt
+ prlen
, trunc
);
6626 memcpy(s
->pwprompt
, prompt
, prompt_len
);
6627 s
->pwprompt
[prompt_len
] = '\0';
6631 "<server failed to send prompt>: ");
6633 s
->echo
= ssh2_pkt_getbool(pktin
);
6639 if (!s
->method
&& s
->can_passwd
) {
6640 s
->method
= AUTH_PASSWORD
;
6641 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6642 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
6643 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
6650 if (!ssh_get_line(s
->pwprompt
, s
->password
,
6651 sizeof(s
->password
), TRUE
)) {
6653 * get_line failed to get a password (for
6654 * example because one was supplied on the
6655 * command line which has already failed to
6658 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6659 ssh2_pkt_adduint32(s
->pktout
,SSH2_DISCONNECT_BY_APPLICATION
);
6660 ssh2_pkt_addstring(s
->pktout
, "No more passwords available"
6662 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6663 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6664 logevent("Unable to authenticate");
6665 connection_fatal(ssh
->frontend
,
6666 "Unable to authenticate");
6667 ssh
->close_expected
= TRUE
;
6668 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6672 int ret
; /* need not be saved across crReturn */
6673 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
6676 setup_userpass_input(ssh
, s
->password
,
6677 sizeof(s
->password
), s
->echo
);
6679 crWaitUntilV(!pktin
);
6680 ret
= process_userpass_input(ssh
, in
, inlen
);
6684 c_write_str(ssh
, "\r\n");
6688 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
6690 * We have our passphrase. Now try the actual authentication.
6692 struct ssh2_userkey
*key
;
6693 const char *error
= NULL
;
6695 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
,
6697 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
6698 if (key
== SSH2_WRONG_PASSPHRASE
) {
6699 c_write_str(ssh
, "Wrong passphrase\r\n");
6700 s
->tried_pubkey_config
= FALSE
;
6702 c_write_str(ssh
, "Unable to load private key (");
6703 c_write_str(ssh
, error
);
6704 c_write_str(ssh
, ")\r\n");
6705 s
->tried_pubkey_config
= TRUE
;
6707 /* Send a spurious AUTH_NONE to return to the top. */
6708 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6709 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6710 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6711 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6712 ssh2_pkt_send(ssh
, s
->pktout
);
6713 s
->type
= AUTH_TYPE_NONE
;
6715 unsigned char *pkblob
, *sigblob
, *sigdata
;
6716 int pkblob_len
, sigblob_len
, sigdata_len
;
6720 * We have loaded the private key and the server
6721 * has announced that it's willing to accept it.
6722 * Hallelujah. Generate a signature and send it.
6724 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6725 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6726 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6727 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6728 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6729 ssh2_pkt_addstring(s
->pktout
, key
->alg
->name
);
6730 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
6731 ssh2_pkt_addstring_start(s
->pktout
);
6732 ssh2_pkt_addstring_data(s
->pktout
, (char *)pkblob
, pkblob_len
);
6735 * The data to be signed is:
6739 * followed by everything so far placed in the
6742 sigdata_len
= s
->pktout
->length
- 5 + 4 + 20;
6743 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6745 sigdata
= snewn(sigdata_len
, unsigned char);
6747 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6748 PUT_32BIT(sigdata
+p
, 20);
6751 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
6752 memcpy(sigdata
+p
, s
->pktout
->data
+ 5,
6753 s
->pktout
->length
- 5);
6754 p
+= s
->pktout
->length
- 5;
6755 assert(p
== sigdata_len
);
6756 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
6757 sigdata_len
, &sigblob_len
);
6758 ssh2_add_sigblob(ssh
, s
->pktout
, pkblob
, pkblob_len
,
6759 sigblob
, sigblob_len
);
6764 ssh2_pkt_send(ssh
, s
->pktout
);
6765 s
->type
= AUTH_TYPE_PUBLICKEY
;
6766 key
->alg
->freekey(key
->data
);
6768 } else if (s
->method
== AUTH_PASSWORD
) {
6770 * We pad out the password packet to 256 bytes to make
6771 * it harder for an attacker to find the length of the
6774 * Anyone using a password longer than 256 bytes
6775 * probably doesn't have much to worry about from
6776 * people who find out how long their password is!
6778 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6779 s
->pktout
->forcepad
= 256;
6780 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6781 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6782 ssh2_pkt_addstring(s
->pktout
, "password");
6783 ssh2_pkt_addbool(s
->pktout
, FALSE
);
6784 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6785 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6786 memset(s
->password
, 0, sizeof(s
->password
));
6787 end_log_omission(ssh
, s
->pktout
);
6788 ssh2_pkt_send(ssh
, s
->pktout
);
6789 logevent("Sent password");
6790 s
->type
= AUTH_TYPE_PASSWORD
;
6791 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
6792 if (s
->curr_prompt
== 0) {
6793 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
6794 ssh2_pkt_adduint32(s
->pktout
, s
->num_prompts
);
6796 if (s
->need_pw
) { /* only add pw if we just got one! */
6797 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6798 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6799 memset(s
->password
, 0, sizeof(s
->password
));
6800 end_log_omission(ssh
, s
->pktout
);
6803 if (s
->curr_prompt
>= s
->num_prompts
) {
6804 ssh2_pkt_send(ssh
, s
->pktout
);
6807 * If there are prompts remaining, we set
6808 * `gotit' so that we won't attempt to get
6809 * another packet. Then we go back round the
6810 * loop and will end up retrieving another
6811 * prompt out of the existing packet. Funky or
6816 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6818 c_write_str(ssh
, "No supported authentication methods"
6819 " left to try!\r\n");
6820 logevent("No supported authentications offered."
6822 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6823 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
6824 ssh2_pkt_addstring(s
->pktout
, "No supported authentication"
6825 " methods available");
6826 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6827 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6828 ssh
->close_expected
= TRUE
;
6829 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6833 } while (!s
->we_are_in
);
6836 * Now we're authenticated for the connection protocol. The
6837 * connection protocol will automatically have started at this
6838 * point; there's no need to send SERVICE_REQUEST.
6841 ssh
->channels
= newtree234(ssh_channelcmp
);
6844 * Set up handlers for some connection protocol messages, so we
6845 * don't have to handle them repeatedly in this coroutine.
6847 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] =
6848 ssh2_msg_channel_window_adjust
;
6849 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] =
6850 ssh2_msg_global_request
;
6853 * Create the main session channel.
6855 if (!ssh
->cfg
.ssh_no_shell
) {
6856 ssh
->mainchan
= snew(struct ssh_channel
);
6857 ssh
->mainchan
->ssh
= ssh
;
6858 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
6859 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
6860 ssh2_pkt_addstring(s
->pktout
, "session");
6861 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->localid
);
6862 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6863 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
6864 ssh2_pkt_adduint32(s
->pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
6865 ssh2_pkt_send(ssh
, s
->pktout
);
6866 crWaitUntilV(pktin
);
6867 if (pktin
->type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
6868 bombout(("Server refused to open a session"));
6870 /* FIXME: error data comes back in FAILURE packet */
6872 if (ssh_pkt_getuint32(pktin
) != ssh
->mainchan
->localid
) {
6873 bombout(("Server's channel confirmation cited wrong channel"));
6876 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(pktin
);
6877 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
6878 ssh
->mainchan
->closes
= 0;
6879 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
6880 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
6881 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
6882 add234(ssh
->channels
, ssh
->mainchan
);
6883 update_specials_menu(ssh
->frontend
);
6884 logevent("Opened channel for session");
6886 ssh
->mainchan
= NULL
;
6889 * Now we have a channel, make dispatch table entries for
6890 * general channel-based messages.
6892 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] =
6893 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] =
6894 ssh2_msg_channel_data
;
6895 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = ssh2_msg_channel_eof
;
6896 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = ssh2_msg_channel_close
;
6897 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] =
6898 ssh2_msg_channel_open_confirmation
;
6899 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] =
6900 ssh2_msg_channel_open_failure
;
6901 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] =
6902 ssh2_msg_channel_request
;
6903 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] =
6904 ssh2_msg_channel_open
;
6907 * Potentially enable X11 forwarding.
6909 if (ssh
->mainchan
&& ssh
->cfg
.x11_forward
) {
6910 char proto
[20], data
[64];
6911 logevent("Requesting X11 forwarding");
6912 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
6913 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
6914 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
6915 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6916 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6917 ssh2_pkt_addstring(s
->pktout
, "x11-req");
6918 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6919 ssh2_pkt_addbool(s
->pktout
, 0); /* many connections */
6920 ssh2_pkt_addstring(s
->pktout
, proto
);
6921 ssh2_pkt_addstring(s
->pktout
, data
);
6922 ssh2_pkt_adduint32(s
->pktout
, x11_get_screen_number(ssh
->cfg
.x11_display
));
6923 ssh2_pkt_send(ssh
, s
->pktout
);
6925 crWaitUntilV(pktin
);
6927 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6928 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6929 bombout(("Unexpected response to X11 forwarding request:"
6930 " packet type %d", pktin
->type
));
6933 logevent("X11 forwarding refused");
6935 logevent("X11 forwarding enabled");
6936 ssh
->X11_fwd_enabled
= TRUE
;
6941 * Enable port forwardings.
6943 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
6946 * Potentially enable agent forwarding.
6948 if (ssh
->mainchan
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
6949 logevent("Requesting OpenSSH-style agent forwarding");
6950 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6951 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6952 ssh2_pkt_addstring(s
->pktout
, "auth-agent-req@openssh.com");
6953 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6954 ssh2_pkt_send(ssh
, s
->pktout
);
6956 crWaitUntilV(pktin
);
6958 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6959 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6960 bombout(("Unexpected response to agent forwarding request:"
6961 " packet type %d", pktin
->type
));
6964 logevent("Agent forwarding refused");
6966 logevent("Agent forwarding enabled");
6967 ssh
->agentfwd_enabled
= TRUE
;
6972 * Now allocate a pty for the session.
6974 if (ssh
->mainchan
&& !ssh
->cfg
.nopty
) {
6975 /* Unpick the terminal-speed string. */
6976 /* XXX perhaps we should allow no speeds to be sent. */
6977 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
6978 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
6979 /* Build the pty request. */
6980 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6981 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
6982 ssh2_pkt_addstring(s
->pktout
, "pty-req");
6983 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6984 ssh2_pkt_addstring(s
->pktout
, ssh
->cfg
.termtype
);
6985 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_width
);
6986 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_height
);
6987 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel width */
6988 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel height */
6989 ssh2_pkt_addstring_start(s
->pktout
);
6990 ssh2_pkt_addbyte(s
->pktout
, 128); /* TTY_OP_ISPEED */
6991 ssh2_pkt_adduint32(s
->pktout
, ssh
->ispeed
);
6992 ssh2_pkt_addbyte(s
->pktout
, 129); /* TTY_OP_OSPEED */
6993 ssh2_pkt_adduint32(s
->pktout
, ssh
->ospeed
);
6994 ssh2_pkt_addstring_data(s
->pktout
, "\0", 1); /* TTY_OP_END */
6995 ssh2_pkt_send(ssh
, s
->pktout
);
6996 ssh
->state
= SSH_STATE_INTERMED
;
6998 crWaitUntilV(pktin
);
7000 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7001 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7002 bombout(("Unexpected response to pty request:"
7003 " packet type %d", pktin
->type
));
7006 c_write_str(ssh
, "Server refused to allocate pty\r\n");
7007 ssh
->editing
= ssh
->echoing
= 1;
7009 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
7010 ssh
->ospeed
, ssh
->ispeed
);
7013 ssh
->editing
= ssh
->echoing
= 1;
7017 * Send environment variables.
7019 * Simplest thing here is to send all the requests at once, and
7020 * then wait for a whole bunch of successes or failures.
7022 if (ssh
->mainchan
&& *ssh
->cfg
.environmt
) {
7023 char *e
= ssh
->cfg
.environmt
;
7024 char *var
, *varend
, *val
;
7030 while (*e
&& *e
!= '\t') e
++;
7032 if (*e
== '\t') e
++;
7037 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7038 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7039 ssh2_pkt_addstring(s
->pktout
, "env");
7040 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7041 ssh2_pkt_addstring_start(s
->pktout
);
7042 ssh2_pkt_addstring_data(s
->pktout
, var
, varend
-var
);
7043 ssh2_pkt_addstring(s
->pktout
, val
);
7044 ssh2_pkt_send(ssh
, s
->pktout
);
7049 logeventf(ssh
, "Sent %d environment variables", s
->num_env
);
7052 s
->env_left
= s
->num_env
;
7054 while (s
->env_left
> 0) {
7055 crWaitUntilV(pktin
);
7057 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7058 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7059 bombout(("Unexpected response to environment request:"
7060 " packet type %d", pktin
->type
));
7070 if (s
->env_ok
== s
->num_env
) {
7071 logevent("All environment variables successfully set");
7072 } else if (s
->env_ok
== 0) {
7073 logevent("All environment variables refused");
7074 c_write_str(ssh
, "Server refused to set environment variables\r\n");
7076 logeventf(ssh
, "%d environment variables refused",
7077 s
->num_env
- s
->env_ok
);
7078 c_write_str(ssh
, "Server refused to set all environment variables\r\n");
7083 * Start a shell or a remote command. We may have to attempt
7084 * this twice if the config data has provided a second choice
7087 if (ssh
->mainchan
) while (1) {
7091 if (ssh
->fallback_cmd
) {
7092 subsys
= ssh
->cfg
.ssh_subsys2
;
7093 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
7095 subsys
= ssh
->cfg
.ssh_subsys
;
7096 cmd
= ssh
->cfg
.remote_cmd_ptr
;
7099 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7100 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7102 ssh2_pkt_addstring(s
->pktout
, "subsystem");
7103 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7104 ssh2_pkt_addstring(s
->pktout
, cmd
);
7106 ssh2_pkt_addstring(s
->pktout
, "exec");
7107 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7108 ssh2_pkt_addstring(s
->pktout
, cmd
);
7110 ssh2_pkt_addstring(s
->pktout
, "shell");
7111 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7113 ssh2_pkt_send(ssh
, s
->pktout
);
7115 crWaitUntilV(pktin
);
7117 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7118 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7119 bombout(("Unexpected response to shell/command request:"
7120 " packet type %d", pktin
->type
));
7124 * We failed to start the command. If this is the
7125 * fallback command, we really are finished; if it's
7126 * not, and if the fallback command exists, try falling
7127 * back to it before complaining.
7129 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
7130 logevent("Primary command failed; attempting fallback");
7131 ssh
->fallback_cmd
= TRUE
;
7134 bombout(("Server refused to start a shell/command"));
7137 logevent("Started a shell/command");
7142 ssh
->state
= SSH_STATE_SESSION
;
7143 if (ssh
->size_needed
)
7144 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
7145 if (ssh
->eof_needed
)
7146 ssh_special(ssh
, TS_EOF
);
7152 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
7157 s
->try_send
= FALSE
;
7161 * _All_ the connection-layer packets we expect to
7162 * receive are now handled by the dispatch table.
7163 * Anything that reaches here must be bogus.
7166 bombout(("Strange packet received: type %d", pktin
->type
));
7168 } else if (ssh
->mainchan
) {
7170 * We have spare data. Add it to the channel buffer.
7172 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
7177 struct ssh_channel
*c
;
7179 * Try to send data on all channels if we can.
7181 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
7184 continue; /* don't send on closing channels */
7185 bufsize
= ssh2_try_send(c
);
7188 case CHAN_MAINSESSION
:
7189 /* stdin need not receive an unthrottle
7190 * notification since it will be polled */
7193 x11_unthrottle(c
->u
.x11
.s
);
7196 /* agent sockets are request/response and need no
7197 * buffer management */
7200 pfd_unthrottle(c
->u
.pfd
.s
);
7212 * Handlers for SSH2 messages that might arrive at any moment.
7214 void ssh2_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
7216 /* log reason code in disconnect message */
7218 int nowlen
, reason
, msglen
;
7220 reason
= ssh_pkt_getuint32(pktin
);
7221 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7223 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
7224 buf
= dupprintf("Received disconnect message (%s)",
7225 ssh2_disconnect_reasons
[reason
]);
7227 buf
= dupprintf("Received disconnect message (unknown"
7228 " type %d)", reason
);
7232 buf
= dupprintf("Disconnection message text: %n%.*s",
7233 &nowlen
, msglen
, msg
);
7235 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7237 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
7238 ssh2_disconnect_reasons
[reason
] : "unknown",
7243 void ssh2_msg_debug(Ssh ssh
, struct Packet
*pktin
)
7245 /* log the debug message */
7250 /* XXX maybe we should actually take notice of this */
7251 always_display
= ssh2_pkt_getbool(pktin
);
7252 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7254 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
7259 void ssh2_msg_something_unimplemented(Ssh ssh
, struct Packet
*pktin
)
7261 struct Packet
*pktout
;
7262 pktout
= ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
7263 ssh2_pkt_adduint32(pktout
, pktin
->sequence
);
7265 * UNIMPLEMENTED messages MUST appear in the same order as the
7266 * messages they respond to. Hence, never queue them.
7268 ssh2_pkt_send_noqueue(ssh
, pktout
);
7272 * Handle the top-level SSH2 protocol.
7274 static void ssh2_protocol_setup(Ssh ssh
)
7279 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7281 for (i
= 0; i
< 256; i
++)
7282 ssh
->packet_dispatch
[i
] = ssh2_msg_something_unimplemented
;
7285 * Any message we actually understand, we set to NULL so that
7286 * the coroutines will get it.
7288 ssh
->packet_dispatch
[SSH2_MSG_UNIMPLEMENTED
] = NULL
;
7289 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_REQUEST
] = NULL
;
7290 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_ACCEPT
] = NULL
;
7291 ssh
->packet_dispatch
[SSH2_MSG_KEXINIT
] = NULL
;
7292 ssh
->packet_dispatch
[SSH2_MSG_NEWKEYS
] = NULL
;
7293 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_INIT
] = NULL
;
7294 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_REPLY
] = NULL
;
7295 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7296 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7297 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_INIT
] = NULL
;
7298 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_REPLY
] = NULL
;
7299 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_REQUEST
] = NULL
;
7300 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_FAILURE
] = NULL
;
7301 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_SUCCESS
] = NULL
;
7302 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
7303 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_PK_OK
] = NULL
;
7304 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7305 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7306 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_INFO_RESPONSE
] = NULL
;
7307 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] = NULL
;
7308 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_SUCCESS
] = NULL
;
7309 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_FAILURE
] = NULL
;
7310 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] = NULL
;
7311 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] = NULL
;
7312 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] = NULL
;
7313 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] = NULL
;
7314 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] = NULL
;
7315 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] = NULL
;
7316 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = NULL
;
7317 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = NULL
;
7318 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] = NULL
;
7319 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_SUCCESS
] = NULL
;
7320 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_FAILURE
] = NULL
;
7323 * These special message types we install handlers for.
7325 ssh
->packet_dispatch
[SSH2_MSG_DISCONNECT
] = ssh2_msg_disconnect
;
7326 ssh
->packet_dispatch
[SSH2_MSG_IGNORE
] = ssh_msg_ignore
; /* shared with ssh1 */
7327 ssh
->packet_dispatch
[SSH2_MSG_DEBUG
] = ssh2_msg_debug
;
7330 static void ssh2_timer(void *ctx
, long now
)
7334 if (!ssh
->kex_in_progress
&& ssh
->cfg
.ssh_rekey_time
!= 0 &&
7335 now
- ssh
->next_rekey
>= 0) {
7336 do_ssh2_transport(ssh
, "timeout", -1, NULL
);
7340 static void ssh2_protocol(Ssh ssh
, void *vin
, int inlen
,
7341 struct Packet
*pktin
)
7343 unsigned char *in
= (unsigned char *)vin
;
7344 if (ssh
->state
== SSH_STATE_CLOSED
)
7348 ssh
->incoming_data_size
+= pktin
->encrypted_len
;
7349 if (!ssh
->kex_in_progress
&&
7350 ssh
->max_data_size
!= 0 &&
7351 ssh
->incoming_data_size
> ssh
->max_data_size
)
7352 do_ssh2_transport(ssh
, "too much data received", -1, NULL
);
7355 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
7356 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
7360 if (!ssh
->protocol_initial_phase_done
||
7361 (pktin
&& pktin
->type
>= 20 && pktin
->type
< 50)) {
7362 if (do_ssh2_transport(ssh
, in
, inlen
, pktin
) &&
7363 !ssh
->protocol_initial_phase_done
) {
7364 ssh
->protocol_initial_phase_done
= TRUE
;
7366 * Allow authconn to initialise itself.
7368 do_ssh2_authconn(ssh
, NULL
, 0, NULL
);
7371 do_ssh2_authconn(ssh
, in
, inlen
, pktin
);
7376 * Called to set up the connection.
7378 * Returns an error message, or NULL on success.
7380 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
7382 char *host
, int port
, char **realhost
, int nodelay
,
7388 ssh
= snew(struct ssh_tag
);
7389 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7390 ssh
->version
= 0; /* when not ready yet */
7393 ssh
->v1_cipher_ctx
= NULL
;
7394 ssh
->crcda_ctx
= NULL
;
7395 ssh
->cscipher
= NULL
;
7396 ssh
->cs_cipher_ctx
= NULL
;
7397 ssh
->sccipher
= NULL
;
7398 ssh
->sc_cipher_ctx
= NULL
;
7400 ssh
->cs_mac_ctx
= NULL
;
7402 ssh
->sc_mac_ctx
= NULL
;
7404 ssh
->cs_comp_ctx
= NULL
;
7406 ssh
->sc_comp_ctx
= NULL
;
7408 ssh
->kex_ctx
= NULL
;
7409 ssh
->hostkey
= NULL
;
7411 ssh
->close_expected
= FALSE
;
7412 ssh
->state
= SSH_STATE_PREPACKET
;
7413 ssh
->size_needed
= FALSE
;
7414 ssh
->eof_needed
= FALSE
;
7417 ssh
->deferred_send_data
= NULL
;
7418 ssh
->deferred_len
= 0;
7419 ssh
->deferred_size
= 0;
7420 ssh
->fallback_cmd
= 0;
7422 ssh
->x11auth
= NULL
;
7423 ssh
->v1_compressing
= FALSE
;
7424 ssh
->v2_outgoing_sequence
= 0;
7425 ssh
->ssh1_rdpkt_crstate
= 0;
7426 ssh
->ssh2_rdpkt_crstate
= 0;
7427 ssh
->do_ssh_init_crstate
= 0;
7428 ssh
->ssh_gotdata_crstate
= 0;
7429 ssh
->do_ssh1_connection_crstate
= 0;
7430 ssh
->do_ssh1_login_crstate
= 0;
7431 ssh
->do_ssh2_transport_crstate
= 0;
7432 ssh
->do_ssh2_authconn_crstate
= 0;
7433 ssh
->do_ssh_init_state
= NULL
;
7434 ssh
->do_ssh1_login_state
= NULL
;
7435 ssh
->do_ssh2_transport_state
= NULL
;
7436 ssh
->do_ssh2_authconn_state
= NULL
;
7437 ssh
->mainchan
= NULL
;
7438 ssh
->throttled_all
= 0;
7439 ssh
->v1_stdout_throttling
= 0;
7441 ssh
->queuelen
= ssh
->queuesize
= 0;
7442 ssh
->queueing
= FALSE
;
7443 ssh
->qhead
= ssh
->qtail
= NULL
;
7444 ssh
->deferred_rekey_reason
= NULL
;
7446 *backend_handle
= ssh
;
7449 if (crypto_startup() == 0)
7450 return "Microsoft high encryption pack not installed!";
7453 ssh
->frontend
= frontend_handle
;
7454 ssh
->term_width
= ssh
->cfg
.width
;
7455 ssh
->term_height
= ssh
->cfg
.height
;
7457 ssh
->channels
= NULL
;
7458 ssh
->rportfwds
= NULL
;
7459 ssh
->portfwds
= NULL
;
7464 ssh
->v1_throttle_count
= 0;
7465 ssh
->overall_bufsize
= 0;
7466 ssh
->fallback_cmd
= 0;
7468 ssh
->protocol
= NULL
;
7470 ssh
->protocol_initial_phase_done
= FALSE
;
7474 ssh
->incoming_data_size
= ssh
->outgoing_data_size
=
7475 ssh
->deferred_data_size
= 0L;
7476 ssh
->max_data_size
= parse_blocksize(ssh
->cfg
.ssh_rekey_data
);
7477 ssh
->kex_in_progress
= FALSE
;
7479 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
7488 static void ssh_free(void *handle
)
7490 Ssh ssh
= (Ssh
) handle
;
7491 struct ssh_channel
*c
;
7492 struct ssh_rportfwd
*pf
;
7494 if (ssh
->v1_cipher_ctx
)
7495 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
7496 if (ssh
->cs_cipher_ctx
)
7497 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
7498 if (ssh
->sc_cipher_ctx
)
7499 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
7500 if (ssh
->cs_mac_ctx
)
7501 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
7502 if (ssh
->sc_mac_ctx
)
7503 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
7504 if (ssh
->cs_comp_ctx
) {
7506 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
7508 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
7510 if (ssh
->sc_comp_ctx
) {
7512 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
7514 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
7517 dh_cleanup(ssh
->kex_ctx
);
7518 sfree(ssh
->savedhost
);
7520 while (ssh
->queuelen
-- > 0)
7521 ssh_free_packet(ssh
->queue
[ssh
->queuelen
]);
7524 while (ssh
->qhead
) {
7525 struct queued_handler
*qh
= ssh
->qhead
;
7526 ssh
->qhead
= qh
->next
;
7529 ssh
->qhead
= ssh
->qtail
= NULL
;
7531 if (ssh
->channels
) {
7532 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
7535 if (c
->u
.x11
.s
!= NULL
)
7536 x11_close(c
->u
.x11
.s
);
7539 if (c
->u
.pfd
.s
!= NULL
)
7540 pfd_close(c
->u
.pfd
.s
);
7545 freetree234(ssh
->channels
);
7546 ssh
->channels
= NULL
;
7549 if (ssh
->rportfwds
) {
7550 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
7552 freetree234(ssh
->rportfwds
);
7553 ssh
->rportfwds
= NULL
;
7555 sfree(ssh
->deferred_send_data
);
7557 x11_free_auth(ssh
->x11auth
);
7558 sfree(ssh
->do_ssh_init_state
);
7559 sfree(ssh
->do_ssh1_login_state
);
7560 sfree(ssh
->do_ssh2_transport_state
);
7561 sfree(ssh
->do_ssh2_authconn_state
);
7562 if (ssh
->crcda_ctx
) {
7563 crcda_free_context(ssh
->crcda_ctx
);
7564 ssh
->crcda_ctx
= NULL
;
7567 ssh_do_close(ssh
, TRUE
);
7568 expire_timer_context(ssh
);
7570 pinger_free(ssh
->pinger
);
7577 * Reconfigure the SSH backend.
7579 static void ssh_reconfig(void *handle
, Config
*cfg
)
7581 Ssh ssh
= (Ssh
) handle
;
7582 char *rekeying
= NULL
, rekey_mandatory
= FALSE
;
7583 unsigned long old_max_data_size
;
7585 pinger_reconfig(ssh
->pinger
, &ssh
->cfg
, cfg
);
7586 ssh_setup_portfwd(ssh
, cfg
);
7588 if (ssh
->cfg
.ssh_rekey_time
!= cfg
->ssh_rekey_time
&&
7589 cfg
->ssh_rekey_time
!= 0) {
7590 long new_next
= ssh
->last_rekey
+ cfg
->ssh_rekey_time
*60*TICKSPERSEC
;
7591 long now
= GETTICKCOUNT();
7593 if (new_next
- now
< 0) {
7594 rekeying
= "timeout shortened";
7596 ssh
->next_rekey
= schedule_timer(new_next
- now
, ssh2_timer
, ssh
);
7600 old_max_data_size
= ssh
->max_data_size
;
7601 ssh
->max_data_size
= parse_blocksize(cfg
->ssh_rekey_data
);
7602 if (old_max_data_size
!= ssh
->max_data_size
&&
7603 ssh
->max_data_size
!= 0) {
7604 if (ssh
->outgoing_data_size
> ssh
->max_data_size
||
7605 ssh
->incoming_data_size
> ssh
->max_data_size
)
7606 rekeying
= "data limit lowered";
7609 if (ssh
->cfg
.compression
!= cfg
->compression
) {
7610 rekeying
= "compression setting changed";
7611 rekey_mandatory
= TRUE
;
7614 if (ssh
->cfg
.ssh2_des_cbc
!= cfg
->ssh2_des_cbc
||
7615 memcmp(ssh
->cfg
.ssh_cipherlist
, cfg
->ssh_cipherlist
,
7616 sizeof(ssh
->cfg
.ssh_cipherlist
))) {
7617 rekeying
= "cipher settings changed";
7618 rekey_mandatory
= TRUE
;
7621 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7624 if (!ssh
->kex_in_progress
) {
7625 do_ssh2_transport(ssh
, rekeying
, -1, NULL
);
7626 } else if (rekey_mandatory
) {
7627 ssh
->deferred_rekey_reason
= rekeying
;
7633 * Called to send data down the Telnet connection.
7635 static int ssh_send(void *handle
, char *buf
, int len
)
7637 Ssh ssh
= (Ssh
) handle
;
7639 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7642 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
7644 return ssh_sendbuffer(ssh
);
7648 * Called to query the current amount of buffered stdin data.
7650 static int ssh_sendbuffer(void *handle
)
7652 Ssh ssh
= (Ssh
) handle
;
7655 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7659 * If the SSH socket itself has backed up, add the total backup
7660 * size on that to any individual buffer on the stdin channel.
7663 if (ssh
->throttled_all
)
7664 override_value
= ssh
->overall_bufsize
;
7666 if (ssh
->version
== 1) {
7667 return override_value
;
7668 } else if (ssh
->version
== 2) {
7669 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
7670 return override_value
;
7672 return (override_value
+
7673 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
7680 * Called to set the size of the window from SSH's POV.
7682 static void ssh_size(void *handle
, int width
, int height
)
7684 Ssh ssh
= (Ssh
) handle
;
7685 struct Packet
*pktout
;
7687 ssh
->term_width
= width
;
7688 ssh
->term_height
= height
;
7690 switch (ssh
->state
) {
7691 case SSH_STATE_BEFORE_SIZE
:
7692 case SSH_STATE_PREPACKET
:
7693 case SSH_STATE_CLOSED
:
7694 break; /* do nothing */
7695 case SSH_STATE_INTERMED
:
7696 ssh
->size_needed
= TRUE
; /* buffer for later */
7698 case SSH_STATE_SESSION
:
7699 if (!ssh
->cfg
.nopty
) {
7700 if (ssh
->version
== 1) {
7701 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
7702 PKT_INT
, ssh
->term_height
,
7703 PKT_INT
, ssh
->term_width
,
7704 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
7705 } else if (ssh
->mainchan
) {
7706 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7707 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7708 ssh2_pkt_addstring(pktout
, "window-change");
7709 ssh2_pkt_addbool(pktout
, 0);
7710 ssh2_pkt_adduint32(pktout
, ssh
->term_width
);
7711 ssh2_pkt_adduint32(pktout
, ssh
->term_height
);
7712 ssh2_pkt_adduint32(pktout
, 0);
7713 ssh2_pkt_adduint32(pktout
, 0);
7714 ssh2_pkt_send(ssh
, pktout
);
7722 * Return a list of the special codes that make sense in this
7725 static const struct telnet_special
*ssh_get_specials(void *handle
)
7727 static const struct telnet_special ssh1_ignore_special
[] = {
7728 {"IGNORE message", TS_NOP
}
7730 static const struct telnet_special ssh2_transport_specials
[] = {
7731 {"IGNORE message", TS_NOP
},
7732 {"Repeat key exchange", TS_REKEY
},
7734 static const struct telnet_special ssh2_session_specials
[] = {
7737 /* These are the signal names defined by draft-ietf-secsh-connect-23.
7738 * They include all the ISO C signals, but are a subset of the POSIX
7739 * required signals. */
7740 {"SIGINT (Interrupt)", TS_SIGINT
},
7741 {"SIGTERM (Terminate)", TS_SIGTERM
},
7742 {"SIGKILL (Kill)", TS_SIGKILL
},
7743 {"SIGQUIT (Quit)", TS_SIGQUIT
},
7744 {"SIGHUP (Hangup)", TS_SIGHUP
},
7745 {"More signals", TS_SUBMENU
},
7746 {"SIGABRT", TS_SIGABRT
}, {"SIGALRM", TS_SIGALRM
},
7747 {"SIGFPE", TS_SIGFPE
}, {"SIGILL", TS_SIGILL
},
7748 {"SIGPIPE", TS_SIGPIPE
}, {"SIGSEGV", TS_SIGSEGV
},
7749 {"SIGUSR1", TS_SIGUSR1
}, {"SIGUSR2", TS_SIGUSR2
},
7752 static const struct telnet_special specials_end
[] = {
7755 /* XXX review this length for any changes: */
7756 static struct telnet_special ssh_specials
[lenof(ssh2_transport_specials
) +
7757 lenof(ssh2_session_specials
) +
7758 lenof(specials_end
)];
7759 Ssh ssh
= (Ssh
) handle
;
7761 #define ADD_SPECIALS(name) \
7763 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7764 memcpy(&ssh_specials[i], name, sizeof name); \
7768 if (ssh
->version
== 1) {
7769 /* Don't bother offering IGNORE if we've decided the remote
7770 * won't cope with it, since we wouldn't bother sending it if
7772 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7773 ADD_SPECIALS(ssh1_ignore_special
);
7774 } else if (ssh
->version
== 2) {
7775 ADD_SPECIALS(ssh2_transport_specials
);
7777 ADD_SPECIALS(ssh2_session_specials
);
7778 } /* else we're not ready yet */
7781 ADD_SPECIALS(specials_end
);
7782 return ssh_specials
;
7790 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7791 * can send an EOF and collect resulting output (e.g. `plink
7794 static void ssh_special(void *handle
, Telnet_Special code
)
7796 Ssh ssh
= (Ssh
) handle
;
7797 struct Packet
*pktout
;
7799 if (code
== TS_EOF
) {
7800 if (ssh
->state
!= SSH_STATE_SESSION
) {
7802 * Buffer the EOF in case we are pre-SESSION, so we can
7803 * send it as soon as we reach SESSION.
7806 ssh
->eof_needed
= TRUE
;
7809 if (ssh
->version
== 1) {
7810 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
7811 } else if (ssh
->mainchan
) {
7812 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
7813 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7814 ssh2_pkt_send(ssh
, pktout
);
7816 logevent("Sent EOF message");
7817 } else if (code
== TS_PING
|| code
== TS_NOP
) {
7818 if (ssh
->state
== SSH_STATE_CLOSED
7819 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7820 if (ssh
->version
== 1) {
7821 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7822 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
7824 pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
7825 ssh2_pkt_addstring_start(pktout
);
7826 ssh2_pkt_send_noqueue(ssh
, pktout
);
7828 } else if (code
== TS_REKEY
) {
7829 if (!ssh
->kex_in_progress
&& ssh
->version
== 2) {
7830 do_ssh2_transport(ssh
, "at user request", -1, NULL
);
7832 } else if (code
== TS_BRK
) {
7833 if (ssh
->state
== SSH_STATE_CLOSED
7834 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7835 if (ssh
->version
== 1) {
7836 logevent("Unable to send BREAK signal in SSH1");
7837 } else if (ssh
->mainchan
) {
7838 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7839 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7840 ssh2_pkt_addstring(pktout
, "break");
7841 ssh2_pkt_addbool(pktout
, 0);
7842 ssh2_pkt_adduint32(pktout
, 0); /* default break length */
7843 ssh2_pkt_send(ssh
, pktout
);
7846 /* Is is a POSIX signal? */
7847 char *signame
= NULL
;
7848 if (code
== TS_SIGABRT
) signame
= "ABRT";
7849 if (code
== TS_SIGALRM
) signame
= "ALRM";
7850 if (code
== TS_SIGFPE
) signame
= "FPE";
7851 if (code
== TS_SIGHUP
) signame
= "HUP";
7852 if (code
== TS_SIGILL
) signame
= "ILL";
7853 if (code
== TS_SIGINT
) signame
= "INT";
7854 if (code
== TS_SIGKILL
) signame
= "KILL";
7855 if (code
== TS_SIGPIPE
) signame
= "PIPE";
7856 if (code
== TS_SIGQUIT
) signame
= "QUIT";
7857 if (code
== TS_SIGSEGV
) signame
= "SEGV";
7858 if (code
== TS_SIGTERM
) signame
= "TERM";
7859 if (code
== TS_SIGUSR1
) signame
= "USR1";
7860 if (code
== TS_SIGUSR2
) signame
= "USR2";
7861 /* The SSH-2 protocol does in principle support arbitrary named
7862 * signals, including signame@domain, but we don't support those. */
7864 /* It's a signal. */
7865 if (ssh
->version
== 2 && ssh
->mainchan
) {
7866 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7867 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7868 ssh2_pkt_addstring(pktout
, "signal");
7869 ssh2_pkt_addbool(pktout
, 0);
7870 ssh2_pkt_addstring(pktout
, signame
);
7871 ssh2_pkt_send(ssh
, pktout
);
7872 logeventf(ssh
, "Sent signal SIG%s", signame
);
7875 /* Never heard of it. Do nothing */
7880 void *new_sock_channel(void *handle
, Socket s
)
7882 Ssh ssh
= (Ssh
) handle
;
7883 struct ssh_channel
*c
;
7884 c
= snew(struct ssh_channel
);
7888 c
->remoteid
= -1; /* to be set when open confirmed */
7889 c
->localid
= alloc_channel_id(ssh
);
7891 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
7893 bufchain_init(&c
->v
.v2
.outbuffer
);
7894 add234(ssh
->channels
, c
);
7900 * This is called when stdout/stderr (the entity to which
7901 * from_backend sends data) manages to clear some backlog.
7903 static void ssh_unthrottle(void *handle
, int bufsize
)
7905 Ssh ssh
= (Ssh
) handle
;
7906 if (ssh
->version
== 1) {
7907 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
7908 ssh
->v1_stdout_throttling
= 0;
7909 ssh1_throttle(ssh
, -1);
7912 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
7913 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
7917 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
7919 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
7921 struct Packet
*pktout
;
7923 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
7925 if (ssh
->version
== 1) {
7926 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
7927 PKT_INT
, c
->localid
,
7930 /* PKT_STR, <org:orgport>, */
7933 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
7934 ssh2_pkt_addstring(pktout
, "direct-tcpip");
7935 ssh2_pkt_adduint32(pktout
, c
->localid
);
7936 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7937 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);/* our window size */
7938 ssh2_pkt_adduint32(pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
7939 ssh2_pkt_addstring(pktout
, hostname
);
7940 ssh2_pkt_adduint32(pktout
, port
);
7942 * We make up values for the originator data; partly it's
7943 * too much hassle to keep track, and partly I'm not
7944 * convinced the server should be told details like that
7945 * about my local network configuration.
7947 ssh2_pkt_addstring(pktout
, "client-side-connection");
7948 ssh2_pkt_adduint32(pktout
, 0);
7949 ssh2_pkt_send(ssh
, pktout
);
7953 static Socket
ssh_socket(void *handle
)
7955 Ssh ssh
= (Ssh
) handle
;
7959 static int ssh_sendok(void *handle
)
7961 Ssh ssh
= (Ssh
) handle
;
7962 return ssh
->send_ok
;
7965 static int ssh_ldisc(void *handle
, int option
)
7967 Ssh ssh
= (Ssh
) handle
;
7968 if (option
== LD_ECHO
)
7969 return ssh
->echoing
;
7970 if (option
== LD_EDIT
)
7971 return ssh
->editing
;
7975 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
7977 Ssh ssh
= (Ssh
) handle
;
7981 static void ssh_provide_logctx(void *handle
, void *logctx
)
7983 Ssh ssh
= (Ssh
) handle
;
7984 ssh
->logctx
= logctx
;
7987 static int ssh_return_exitcode(void *handle
)
7989 Ssh ssh
= (Ssh
) handle
;
7993 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
7997 * cfg_info for SSH is the currently running version of the
7998 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
8000 static int ssh_cfg_info(void *handle
)
8002 Ssh ssh
= (Ssh
) handle
;
8003 return ssh
->version
;
8007 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
8008 * that fails. This variable is the means by which scp.c can reach
8009 * into the SSH code and find out which one it got.
8011 extern int ssh_fallback_cmd(void *handle
)
8013 Ssh ssh
= (Ssh
) handle
;
8014 return ssh
->fallback_cmd
;
8017 Backend ssh_backend
= {
8027 ssh_return_exitcode
,