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 /* 64 was BUG_SSH2_DH_GEX, now spare */
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
364 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
366 static void *nullmac_make_context(void)
370 static void nullmac_free_context(void *handle
)
373 static void nullmac_key(void *handle
, unsigned char *key
)
376 static void nullmac_generate(void *handle
, unsigned char *blk
, int len
,
380 static int nullmac_verify(void *handle
, unsigned char *blk
, int len
,
385 const static struct ssh_mac ssh_mac_none
= {
386 nullmac_make_context
, nullmac_free_context
, nullmac_key
,
387 nullmac_generate
, nullmac_verify
, "none", 0
389 const static struct ssh_mac
*macs
[] = {
390 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
392 const static struct ssh_mac
*buggymacs
[] = {
393 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
396 static void *ssh_comp_none_init(void)
400 static void ssh_comp_none_cleanup(void *handle
)
403 static int ssh_comp_none_block(void *handle
, unsigned char *block
, int len
,
404 unsigned char **outblock
, int *outlen
)
408 static int ssh_comp_none_disable(void *handle
)
412 const static struct ssh_compress ssh_comp_none
= {
414 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
415 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
416 ssh_comp_none_disable
, NULL
418 extern const struct ssh_compress ssh_zlib
;
419 const static struct ssh_compress
*compressions
[] = {
420 &ssh_zlib
, &ssh_comp_none
423 enum { /* channel types */
428 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
432 * 2-3-4 tree storing channels.
435 Ssh ssh
; /* pointer back to main context */
436 unsigned remoteid
, localid
;
439 * In SSH1, this value contains four bits:
441 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
442 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
443 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
444 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
446 * A channel is completely finished with when all four bits are set.
450 struct ssh1_data_channel
{
453 struct ssh2_data_channel
{
455 unsigned remwindow
, remmaxpkt
;
460 struct ssh_agent_channel
{
461 unsigned char *message
;
462 unsigned char msglen
[4];
463 unsigned lensofar
, totallen
;
465 struct ssh_x11_channel
{
468 struct ssh_pfd_channel
{
475 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
476 * 2 use this structure in different ways, reflecting SSH 2's
477 * altogether saner approach to port forwarding.
479 * In SSH 1, you arrange a remote forwarding by sending the server
480 * the remote port number, and the local destination host:port.
481 * When a connection comes in, the server sends you back that
482 * host:port pair, and you connect to it. This is a ready-made
483 * security hole if you're not on the ball: a malicious server
484 * could send you back _any_ host:port pair, so if you trustingly
485 * connect to the address it gives you then you've just opened the
486 * entire inside of your corporate network just by connecting
487 * through it to a dodgy SSH server. Hence, we must store a list of
488 * host:port pairs we _are_ trying to forward to, and reject a
489 * connection request from the server if it's not in the list.
491 * In SSH 2, each side of the connection minds its own business and
492 * doesn't send unnecessary information to the other. You arrange a
493 * remote forwarding by sending the server just the remote port
494 * number. When a connection comes in, the server tells you which
495 * of its ports was connected to; and _you_ have to remember what
496 * local host:port pair went with that port number.
498 * Hence, in SSH 1 this structure is indexed by destination
499 * host:port pair, whereas in SSH 2 it is indexed by source port.
501 struct ssh_portfwd
; /* forward declaration */
503 struct ssh_rportfwd
{
504 unsigned sport
, dport
;
507 struct ssh_portfwd
*pfrec
;
509 #define free_rportfwd(pf) ( \
510 ((pf) ? (sfree((pf)->sportdesc)) : (void)0 ), sfree(pf) )
513 * Separately to the rportfwd tree (which is for looking up port
514 * open requests from the server), a tree of _these_ structures is
515 * used to keep track of all the currently open port forwardings,
516 * so that we can reconfigure in mid-session if the user requests
520 enum { DESTROY
, KEEP
, CREATE
} status
;
522 unsigned sport
, dport
;
525 struct ssh_rportfwd
*remote
;
529 #define free_portfwd(pf) ( \
530 ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr), \
531 sfree((pf)->sserv), sfree((pf)->dserv)) : (void)0 ), sfree(pf) )
536 unsigned long sequence
;
541 long encrypted_len
; /* for SSH2 total-size counting */
544 * State associated with packet logging
548 struct logblank_t
*blanks
;
551 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
552 struct Packet
*pktin
);
553 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
554 struct Packet
*pktin
);
555 static void ssh1_protocol_setup(Ssh ssh
);
556 static void ssh2_protocol_setup(Ssh ssh
);
557 static void ssh_size(void *handle
, int width
, int height
);
558 static void ssh_special(void *handle
, Telnet_Special
);
559 static int ssh2_try_send(struct ssh_channel
*c
);
560 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
561 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
562 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
563 static int ssh_sendbuffer(void *handle
);
564 static void ssh_do_close(Ssh ssh
);
565 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
);
566 static int ssh2_pkt_getbool(struct Packet
*pkt
);
567 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
);
568 static void ssh2_timer(void *ctx
, long now
);
569 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
,
570 struct Packet
*pktin
);
572 struct rdpkt1_state_tag
{
573 long len
, pad
, biglen
, to_read
;
574 unsigned long realcrc
, gotcrc
;
578 struct Packet
*pktin
;
581 struct rdpkt2_state_tag
{
582 long len
, pad
, payload
, packetlen
, maclen
;
585 unsigned long incoming_sequence
;
586 struct Packet
*pktin
;
589 typedef void (*handler_fn_t
)(Ssh ssh
, struct Packet
*pktin
);
590 typedef void (*chandler_fn_t
)(Ssh ssh
, struct Packet
*pktin
, void *ctx
);
592 struct queued_handler
;
593 struct queued_handler
{
595 chandler_fn_t handler
;
597 struct queued_handler
*next
;
601 const struct plug_function_table
*fn
;
602 /* the above field _must_ be first in the structure */
604 SHA_State exhash
, exhashbase
;
611 unsigned char session_key
[32];
613 int v1_remote_protoflags
;
614 int v1_local_protoflags
;
615 int agentfwd_enabled
;
618 const struct ssh_cipher
*cipher
;
621 const struct ssh2_cipher
*cscipher
, *sccipher
;
622 void *cs_cipher_ctx
, *sc_cipher_ctx
;
623 const struct ssh_mac
*csmac
, *scmac
;
624 void *cs_mac_ctx
, *sc_mac_ctx
;
625 const struct ssh_compress
*cscomp
, *sccomp
;
626 void *cs_comp_ctx
, *sc_comp_ctx
;
627 const struct ssh_kex
*kex
;
628 const struct ssh_signkey
*hostkey
;
629 unsigned char v2_session_id
[20];
635 int echoing
, editing
;
639 int ospeed
, ispeed
; /* temporaries */
640 int term_width
, term_height
;
642 tree234
*channels
; /* indexed by local id */
643 struct ssh_channel
*mainchan
; /* primary session channel */
646 tree234
*rportfwds
, *portfwds
;
650 SSH_STATE_BEFORE_SIZE
,
656 int size_needed
, eof_needed
;
658 struct Packet
**queue
;
659 int queuelen
, queuesize
;
661 unsigned char *deferred_send_data
;
662 int deferred_len
, deferred_size
;
665 * Gross hack: pscp will try to start SFTP but fall back to
666 * scp1 if that fails. This variable is the means by which
667 * scp.c can reach into the SSH code and find out which one it
673 * Used for username and password input.
675 char *userpass_input_buffer
;
676 int userpass_input_buflen
;
677 int userpass_input_bufpos
;
678 int userpass_input_echo
;
685 int v1_throttle_count
;
688 int v1_stdout_throttling
;
689 int v2_outgoing_sequence
;
691 int ssh1_rdpkt_crstate
;
692 int ssh2_rdpkt_crstate
;
693 int do_ssh_init_crstate
;
694 int ssh_gotdata_crstate
;
695 int do_ssh1_login_crstate
;
696 int do_ssh1_connection_crstate
;
697 int do_ssh2_transport_crstate
;
698 int do_ssh2_authconn_crstate
;
700 void *do_ssh_init_state
;
701 void *do_ssh1_login_state
;
702 void *do_ssh2_transport_state
;
703 void *do_ssh2_authconn_state
;
705 struct rdpkt1_state_tag rdpkt1_state
;
706 struct rdpkt2_state_tag rdpkt2_state
;
708 /* ssh1 and ssh2 use this for different things, but both use it */
709 int protocol_initial_phase_done
;
711 void (*protocol
) (Ssh ssh
, unsigned char *in
, int inlen
,
713 struct Packet
*(*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
716 * We maintain a full _copy_ of a Config structure here, not
717 * merely a pointer to it. That way, when we're passed a new
718 * one for reconfiguration, we can check the differences and
719 * potentially reconfigure port forwardings etc in mid-session.
724 * Used to transfer data back from async agent callbacks.
726 void *agent_response
;
727 int agent_response_len
;
730 * Dispatch table for packet types that we may have to deal
733 handler_fn_t packet_dispatch
[256];
736 * Queues of one-off handler functions for success/failure
737 * indications from a request.
739 struct queued_handler
*qhead
, *qtail
;
742 * This module deals with sending keepalives.
747 * Track incoming and outgoing data sizes and time, for
750 unsigned long incoming_data_size
, outgoing_data_size
, deferred_data_size
;
751 unsigned long max_data_size
;
753 long next_rekey
, last_rekey
;
754 char *deferred_rekey_reason
; /* points to STATIC string; don't free */
757 #define logevent(s) logevent(ssh->frontend, s)
759 /* logevent, only printf-formatted. */
760 static void logeventf(Ssh ssh
, const char *fmt
, ...)
766 buf
= dupvprintf(fmt
, ap
);
772 #define bombout(msg) \
774 char *text = dupprintf msg; \
777 connection_fatal(ssh->frontend, "%s", text); \
781 /* Functions to leave bits out of the SSH packet log file. */
783 static void dont_log_password(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
785 if (ssh
->cfg
.logomitpass
)
786 pkt
->logmode
= blanktype
;
789 static void dont_log_data(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
791 if (ssh
->cfg
.logomitdata
)
792 pkt
->logmode
= blanktype
;
795 static void end_log_omission(Ssh ssh
, struct Packet
*pkt
)
797 pkt
->logmode
= PKTLOG_EMIT
;
800 static int ssh_channelcmp(void *av
, void *bv
)
802 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
803 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
804 if (a
->localid
< b
->localid
)
806 if (a
->localid
> b
->localid
)
810 static int ssh_channelfind(void *av
, void *bv
)
812 unsigned *a
= (unsigned *) av
;
813 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
821 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
823 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
824 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
826 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
827 return i
< 0 ?
-1 : +1;
828 if (a
->dport
> b
->dport
)
830 if (a
->dport
< b
->dport
)
835 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
837 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
838 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
840 if (a
->sport
> b
->sport
)
842 if (a
->sport
< b
->sport
)
848 * Special form of strcmp which can cope with NULL inputs. NULL is
849 * defined to sort before even the empty string.
851 static int nullstrcmp(const char *a
, const char *b
)
853 if (a
== NULL
&& b
== NULL
)
862 static int ssh_portcmp(void *av
, void *bv
)
864 struct ssh_portfwd
*a
= (struct ssh_portfwd
*) av
;
865 struct ssh_portfwd
*b
= (struct ssh_portfwd
*) bv
;
867 if (a
->type
> b
->type
)
869 if (a
->type
< b
->type
)
871 if (a
->addressfamily
> b
->addressfamily
)
873 if (a
->addressfamily
< b
->addressfamily
)
875 if ( (i
= nullstrcmp(a
->saddr
, b
->saddr
)) != 0)
876 return i
< 0 ?
-1 : +1;
877 if (a
->sport
> b
->sport
)
879 if (a
->sport
< b
->sport
)
881 if (a
->type
!= 'D') {
882 if ( (i
= nullstrcmp(a
->daddr
, b
->daddr
)) != 0)
883 return i
< 0 ?
-1 : +1;
884 if (a
->dport
> b
->dport
)
886 if (a
->dport
< b
->dport
)
892 static int alloc_channel_id(Ssh ssh
)
894 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
895 unsigned low
, high
, mid
;
897 struct ssh_channel
*c
;
900 * First-fit allocation of channel numbers: always pick the
901 * lowest unused one. To do this, binary-search using the
902 * counted B-tree to find the largest channel ID which is in a
903 * contiguous sequence from the beginning. (Precisely
904 * everything in that sequence must have ID equal to its tree
905 * index plus CHANNEL_NUMBER_OFFSET.)
907 tsize
= count234(ssh
->channels
);
911 while (high
- low
> 1) {
912 mid
= (high
+ low
) / 2;
913 c
= index234(ssh
->channels
, mid
);
914 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
915 low
= mid
; /* this one is fine */
917 high
= mid
; /* this one is past it */
920 * Now low points to either -1, or the tree index of the
921 * largest ID in the initial sequence.
924 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
925 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
927 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
930 static void c_write(Ssh ssh
, const char *buf
, int len
)
932 if ((flags
& FLAG_STDERR
)) {
934 for (i
= 0; i
< len
; i
++)
936 fputc(buf
[i
], stderr
);
939 from_backend(ssh
->frontend
, 1, buf
, len
);
942 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
945 for (i
= 0; i
< len
; i
++) {
947 c_write(ssh
, "\r\n", 2);
948 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
949 c_write(ssh
, buf
+ i
, 1);
953 static void c_write_str(Ssh ssh
, const char *buf
)
955 c_write(ssh
, buf
, strlen(buf
));
958 static void ssh_free_packet(struct Packet
*pkt
)
963 static struct Packet
*ssh_new_packet(void)
965 struct Packet
*pkt
= snew(struct Packet
);
969 pkt
->logmode
= PKTLOG_EMIT
;
977 * Collect incoming data in the incoming packet buffer.
978 * Decipher and verify the packet when it is completely read.
979 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
980 * Update the *data and *datalen variables.
981 * Return a Packet structure when a packet is completed.
983 static struct Packet
*ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
985 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
987 crBegin(ssh
->ssh1_rdpkt_crstate
);
989 st
->pktin
= ssh_new_packet();
992 st
->pktin
->length
= 0;
994 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
995 while ((*datalen
) == 0)
997 st
->len
= (st
->len
<< 8) + **data
;
998 (*data
)++, (*datalen
)--;
1001 st
->pad
= 8 - (st
->len
% 8);
1002 st
->biglen
= st
->len
+ st
->pad
;
1003 st
->pktin
->length
= st
->len
- 5;
1005 if (st
->biglen
< 0) {
1006 bombout(("Extremely large packet length from server suggests"
1007 " data stream corruption"));
1008 ssh_free_packet(st
->pktin
);
1012 st
->pktin
->maxlen
= st
->biglen
;
1013 st
->pktin
->data
= snewn(st
->biglen
+ APIEXTRA
, unsigned char);
1015 st
->to_read
= st
->biglen
;
1016 st
->p
= st
->pktin
->data
;
1017 while (st
->to_read
> 0) {
1018 st
->chunk
= st
->to_read
;
1019 while ((*datalen
) == 0)
1021 if (st
->chunk
> (*datalen
))
1022 st
->chunk
= (*datalen
);
1023 memcpy(st
->p
, *data
, st
->chunk
);
1025 *datalen
-= st
->chunk
;
1027 st
->to_read
-= st
->chunk
;
1030 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, st
->pktin
->data
,
1031 st
->biglen
, NULL
)) {
1032 bombout(("Network attack (CRC compensation) detected!"));
1033 ssh_free_packet(st
->pktin
);
1038 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, st
->pktin
->data
, st
->biglen
);
1040 st
->realcrc
= crc32_compute(st
->pktin
->data
, st
->biglen
- 4);
1041 st
->gotcrc
= GET_32BIT(st
->pktin
->data
+ st
->biglen
- 4);
1042 if (st
->gotcrc
!= st
->realcrc
) {
1043 bombout(("Incorrect CRC received on packet"));
1044 ssh_free_packet(st
->pktin
);
1048 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1049 st
->pktin
->savedpos
= 0;
1051 if (ssh
->v1_compressing
) {
1052 unsigned char *decompblk
;
1054 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
1055 st
->pktin
->body
- 1, st
->pktin
->length
+ 1,
1056 &decompblk
, &decomplen
)) {
1057 bombout(("Zlib decompression encountered invalid data"));
1058 ssh_free_packet(st
->pktin
);
1062 if (st
->pktin
->maxlen
< st
->pad
+ decomplen
) {
1063 st
->pktin
->maxlen
= st
->pad
+ decomplen
;
1064 st
->pktin
->data
= sresize(st
->pktin
->data
,
1065 st
->pktin
->maxlen
+ APIEXTRA
,
1067 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1070 memcpy(st
->pktin
->body
- 1, decompblk
, decomplen
);
1072 st
->pktin
->length
= decomplen
- 1;
1075 st
->pktin
->type
= st
->pktin
->body
[-1];
1078 * Log incoming packet, possibly omitting sensitive fields.
1082 struct logblank_t blank
;
1083 if (ssh
->cfg
.logomitdata
) {
1084 int do_blank
= FALSE
, blank_prefix
= 0;
1085 /* "Session data" packets - omit the data field */
1086 if ((st
->pktin
->type
== SSH1_SMSG_STDOUT_DATA
) ||
1087 (st
->pktin
->type
== SSH1_SMSG_STDERR_DATA
)) {
1088 do_blank
= TRUE
; blank_prefix
= 0;
1089 } else if (st
->pktin
->type
== SSH1_MSG_CHANNEL_DATA
) {
1090 do_blank
= TRUE
; blank_prefix
= 4;
1093 blank
.offset
= blank_prefix
;
1094 blank
.len
= st
->pktin
->length
;
1095 blank
.type
= PKTLOG_OMIT
;
1099 log_packet(ssh
->logctx
,
1100 PKT_INCOMING
, st
->pktin
->type
,
1101 ssh1_pkt_type(st
->pktin
->type
),
1102 st
->pktin
->body
, st
->pktin
->length
,
1106 crFinish(st
->pktin
);
1109 static struct Packet
*ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1111 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1113 crBegin(ssh
->ssh2_rdpkt_crstate
);
1115 st
->pktin
= ssh_new_packet();
1117 st
->pktin
->type
= 0;
1118 st
->pktin
->length
= 0;
1120 st
->cipherblk
= ssh
->sccipher
->blksize
;
1123 if (st
->cipherblk
< 8)
1126 st
->pktin
->data
= snewn(st
->cipherblk
+ APIEXTRA
, unsigned char);
1129 * Acquire and decrypt the first block of the packet. This will
1130 * contain the length and padding details.
1132 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1133 while ((*datalen
) == 0)
1135 st
->pktin
->data
[st
->i
] = *(*data
)++;
1140 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1141 st
->pktin
->data
, st
->cipherblk
);
1144 * Now get the length and padding figures.
1146 st
->len
= GET_32BIT(st
->pktin
->data
);
1147 st
->pad
= st
->pktin
->data
[4];
1150 * _Completely_ silly lengths should be stomped on before they
1151 * do us any more damage.
1153 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
1154 bombout(("Incoming packet was garbled on decryption"));
1155 ssh_free_packet(st
->pktin
);
1160 * This enables us to deduce the payload length.
1162 st
->payload
= st
->len
- st
->pad
- 1;
1164 st
->pktin
->length
= st
->payload
+ 5;
1167 * So now we can work out the total packet length.
1169 st
->packetlen
= st
->len
+ 4;
1170 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1173 * Allocate memory for the rest of the packet.
1175 st
->pktin
->maxlen
= st
->packetlen
+ st
->maclen
;
1176 st
->pktin
->data
= sresize(st
->pktin
->data
,
1177 st
->pktin
->maxlen
+ APIEXTRA
,
1181 * Read and decrypt the remainder of the packet.
1183 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1185 while ((*datalen
) == 0)
1187 st
->pktin
->data
[st
->i
] = *(*data
)++;
1190 /* Decrypt everything _except_ the MAC. */
1192 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1193 st
->pktin
->data
+ st
->cipherblk
,
1194 st
->packetlen
- st
->cipherblk
);
1196 st
->pktin
->encrypted_len
= st
->packetlen
;
1202 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, st
->pktin
->data
, st
->len
+ 4,
1203 st
->incoming_sequence
)) {
1204 bombout(("Incorrect MAC received on packet"));
1205 ssh_free_packet(st
->pktin
);
1209 st
->pktin
->sequence
= st
->incoming_sequence
++;
1212 * Decompress packet payload.
1215 unsigned char *newpayload
;
1218 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1219 st
->pktin
->data
+ 5, st
->pktin
->length
- 5,
1220 &newpayload
, &newlen
)) {
1221 if (st
->pktin
->maxlen
< newlen
+ 5) {
1222 st
->pktin
->maxlen
= newlen
+ 5;
1223 st
->pktin
->data
= sresize(st
->pktin
->data
,
1224 st
->pktin
->maxlen
+ APIEXTRA
,
1227 st
->pktin
->length
= 5 + newlen
;
1228 memcpy(st
->pktin
->data
+ 5, newpayload
, newlen
);
1233 st
->pktin
->savedpos
= 6;
1234 st
->pktin
->body
= st
->pktin
->data
;
1235 st
->pktin
->type
= st
->pktin
->data
[5];
1238 * Log incoming packet, possibly omitting sensitive fields.
1242 struct logblank_t blank
;
1243 if (ssh
->cfg
.logomitdata
) {
1244 int do_blank
= FALSE
, blank_prefix
= 0;
1245 /* "Session data" packets - omit the data field */
1246 if (st
->pktin
->type
== SSH2_MSG_CHANNEL_DATA
) {
1247 do_blank
= TRUE
; blank_prefix
= 4;
1248 } else if (st
->pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1249 do_blank
= TRUE
; blank_prefix
= 8;
1252 blank
.offset
= blank_prefix
;
1253 blank
.len
= (st
->pktin
->length
-6) - blank_prefix
;
1254 blank
.type
= PKTLOG_OMIT
;
1258 log_packet(ssh
->logctx
, PKT_INCOMING
, st
->pktin
->type
,
1259 ssh2_pkt_type(ssh
->pkt_ctx
, st
->pktin
->type
),
1260 st
->pktin
->data
+6, st
->pktin
->length
-6,
1264 crFinish(st
->pktin
);
1267 static void ssh1_pktout_size(struct Packet
*pkt
, int len
)
1271 len
+= 5; /* type and CRC */
1272 pad
= 8 - (len
% 8);
1275 pkt
->length
= len
- 5;
1276 if (pkt
->maxlen
< biglen
) {
1277 pkt
->maxlen
= biglen
;
1278 pkt
->data
= sresize(pkt
->data
, biglen
+ 4 + APIEXTRA
, unsigned char);
1280 pkt
->body
= pkt
->data
+ 4 + pad
+ 1;
1283 static struct Packet
*s_wrpkt_start(int type
, int len
)
1285 struct Packet
*pkt
= ssh_new_packet();
1286 ssh1_pktout_size(pkt
, len
);
1288 /* Initialise log omission state */
1294 static int s_wrpkt_prepare(Ssh ssh
, struct Packet
*pkt
)
1300 * XXX various versions of SC (including 8.8.4) screw up the
1301 * register allocation in this function and use the same register
1302 * (D6) for len and as a temporary, with predictable results. The
1303 * following sledgehammer prevents this.
1309 pkt
->body
[-1] = pkt
->type
;
1312 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->type
,
1313 ssh1_pkt_type(pkt
->type
),
1314 pkt
->body
, pkt
->length
,
1315 pkt
->nblanks
, pkt
->blanks
);
1316 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1319 if (ssh
->v1_compressing
) {
1320 unsigned char *compblk
;
1322 zlib_compress_block(ssh
->cs_comp_ctx
,
1323 pkt
->body
- 1, pkt
->length
+ 1,
1324 &compblk
, &complen
);
1325 ssh1_pktout_size(pkt
, complen
- 1);
1326 memcpy(pkt
->body
- 1, compblk
, complen
);
1330 len
= pkt
->length
+ 5; /* type and CRC */
1331 pad
= 8 - (len
% 8);
1334 for (i
= 0; i
< pad
; i
++)
1335 pkt
->data
[i
+ 4] = random_byte();
1336 crc
= crc32_compute(pkt
->data
+ 4, biglen
- 4);
1337 PUT_32BIT(pkt
->data
+ biglen
, crc
);
1338 PUT_32BIT(pkt
->data
, len
);
1341 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, pkt
->data
+ 4, biglen
);
1346 static void s_wrpkt(Ssh ssh
, struct Packet
*pkt
)
1349 len
= s_wrpkt_prepare(ssh
, pkt
);
1350 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1351 if (backlog
> SSH_MAX_BACKLOG
)
1352 ssh_throttle_all(ssh
, 1, backlog
);
1355 static void s_wrpkt_defer(Ssh ssh
, struct Packet
*pkt
)
1358 len
= s_wrpkt_prepare(ssh
, pkt
);
1359 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1360 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1361 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1365 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1366 ssh
->deferred_len
+= len
;
1370 * Construct a packet with the specified contents.
1372 static struct Packet
*construct_packet(Ssh ssh
, int pkttype
,
1373 va_list ap1
, va_list ap2
)
1375 unsigned char *p
, *argp
, argchar
;
1376 unsigned long argint
;
1377 int pktlen
, argtype
, arglen
;
1382 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1385 (void) va_arg(ap1
, int);
1389 (void) va_arg(ap1
, int);
1393 (void) va_arg(ap1
, unsigned char *);
1394 arglen
= va_arg(ap1
, int);
1398 argp
= va_arg(ap1
, unsigned char *);
1399 arglen
= strlen((char *)argp
);
1400 pktlen
+= 4 + arglen
;
1403 bn
= va_arg(ap1
, Bignum
);
1404 pktlen
+= ssh1_bignum_length(bn
);
1409 /* ignore this pass */
1416 pkt
= s_wrpkt_start(pkttype
, pktlen
);
1419 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1420 int offset
= p
- pkt
->body
, len
= 0;
1422 /* Actual fields in the packet */
1424 argint
= va_arg(ap2
, int);
1425 PUT_32BIT(p
, argint
);
1429 argchar
= (unsigned char) va_arg(ap2
, int);
1434 argp
= va_arg(ap2
, unsigned char *);
1435 arglen
= va_arg(ap2
, int);
1436 memcpy(p
, argp
, arglen
);
1440 argp
= va_arg(ap2
, unsigned char *);
1441 arglen
= strlen((char *)argp
);
1442 PUT_32BIT(p
, arglen
);
1443 memcpy(p
+ 4, argp
, arglen
);
1447 bn
= va_arg(ap2
, Bignum
);
1448 len
= ssh1_write_bignum(p
, bn
);
1450 /* Tokens for modifications to packet logging */
1452 dont_log_password(ssh
, pkt
, PKTLOG_BLANK
);
1455 dont_log_data(ssh
, pkt
, PKTLOG_OMIT
);
1458 end_log_omission(ssh
, pkt
);
1462 /* Deal with logfile omission, if required. */
1463 if (len
&& (pkt
->logmode
!= PKTLOG_EMIT
)) {
1465 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
,
1467 pkt
->blanks
[pkt
->nblanks
-1].offset
= offset
;
1468 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1469 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1476 static void send_packet(Ssh ssh
, int pkttype
, ...)
1480 va_start(ap1
, pkttype
);
1481 va_start(ap2
, pkttype
);
1482 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1486 ssh_free_packet(pkt
);
1489 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1493 va_start(ap1
, pkttype
);
1494 va_start(ap2
, pkttype
);
1495 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1498 s_wrpkt_defer(ssh
, pkt
);
1499 ssh_free_packet(pkt
);
1502 static int ssh_versioncmp(char *a
, char *b
)
1505 unsigned long av
, bv
;
1507 av
= strtoul(a
, &ae
, 10);
1508 bv
= strtoul(b
, &be
, 10);
1510 return (av
< bv ?
-1 : +1);
1515 av
= strtoul(ae
, &ae
, 10);
1516 bv
= strtoul(be
, &be
, 10);
1518 return (av
< bv ?
-1 : +1);
1523 * Utility routines for putting an SSH-protocol `string' and
1524 * `uint32' into a SHA state.
1527 static void sha_string(SHA_State
* s
, void *str
, int len
)
1529 unsigned char lenblk
[4];
1530 PUT_32BIT(lenblk
, len
);
1531 SHA_Bytes(s
, lenblk
, 4);
1532 SHA_Bytes(s
, str
, len
);
1535 static void sha_uint32(SHA_State
* s
, unsigned i
)
1537 unsigned char intblk
[4];
1538 PUT_32BIT(intblk
, i
);
1539 SHA_Bytes(s
, intblk
, 4);
1543 * SSH2 packet construction functions.
1545 static void ssh2_pkt_ensure(struct Packet
*pkt
, int length
)
1547 if (pkt
->maxlen
< length
) {
1548 pkt
->maxlen
= length
+ 256;
1549 pkt
->data
= sresize(pkt
->data
, pkt
->maxlen
+ APIEXTRA
, unsigned char);
1552 static void ssh2_pkt_adddata(struct Packet
*pkt
, void *data
, int len
)
1554 if (pkt
->logmode
!= PKTLOG_EMIT
) {
1556 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
, struct logblank_t
);
1557 pkt
->blanks
[pkt
->nblanks
-1].offset
= pkt
->length
- 6;
1558 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1559 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1562 ssh2_pkt_ensure(pkt
, pkt
->length
);
1563 memcpy(pkt
->data
+ pkt
->length
- len
, data
, len
);
1565 static void ssh2_pkt_addbyte(struct Packet
*pkt
, unsigned char byte
)
1567 ssh2_pkt_adddata(pkt
, &byte
, 1);
1569 static struct Packet
*ssh2_pkt_init(int pkt_type
)
1571 struct Packet
*pkt
= ssh_new_packet();
1573 ssh2_pkt_addbyte(pkt
, (unsigned char) pkt_type
);
1576 static void ssh2_pkt_addbool(struct Packet
*pkt
, unsigned char value
)
1578 ssh2_pkt_adddata(pkt
, &value
, 1);
1580 static void ssh2_pkt_adduint32(struct Packet
*pkt
, unsigned long value
)
1583 PUT_32BIT(x
, value
);
1584 ssh2_pkt_adddata(pkt
, x
, 4);
1586 static void ssh2_pkt_addstring_start(struct Packet
*pkt
)
1588 ssh2_pkt_adduint32(pkt
, 0);
1589 pkt
->savedpos
= pkt
->length
;
1591 static void ssh2_pkt_addstring_str(struct Packet
*pkt
, char *data
)
1593 ssh2_pkt_adddata(pkt
, data
, strlen(data
));
1594 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1596 static void ssh2_pkt_addstring_data(struct Packet
*pkt
, char *data
, int len
)
1598 ssh2_pkt_adddata(pkt
, data
, len
);
1599 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1601 static void ssh2_pkt_addstring(struct Packet
*pkt
, char *data
)
1603 ssh2_pkt_addstring_start(pkt
);
1604 ssh2_pkt_addstring_str(pkt
, data
);
1606 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1609 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1610 p
= snewn(n
+ 1, unsigned char);
1612 fatalbox("out of memory");
1614 for (i
= 1; i
<= n
; i
++)
1615 p
[i
] = bignum_byte(b
, n
- i
);
1617 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1619 memmove(p
, p
+ i
, n
+ 1 - i
);
1623 static void ssh2_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1627 p
= ssh2_mpint_fmt(b
, &len
);
1628 ssh2_pkt_addstring_start(pkt
);
1629 ssh2_pkt_addstring_data(pkt
, (char *)p
, len
);
1634 * Construct an SSH2 final-form packet: compress it, encrypt it,
1635 * put the MAC on it. Final packet, ready to be sent, is stored in
1636 * pkt->data. Total length is returned.
1638 static int ssh2_pkt_construct(Ssh ssh
, struct Packet
*pkt
)
1640 int cipherblk
, maclen
, padding
, i
;
1643 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[5],
1644 ssh2_pkt_type(ssh
->pkt_ctx
, pkt
->data
[5]),
1645 pkt
->data
+ 6, pkt
->length
- 6,
1646 pkt
->nblanks
, pkt
->blanks
);
1647 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1651 * Compress packet payload.
1654 unsigned char *newpayload
;
1657 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, pkt
->data
+ 5,
1659 &newpayload
, &newlen
)) {
1661 ssh2_pkt_adddata(pkt
, newpayload
, newlen
);
1667 * Add padding. At least four bytes, and must also bring total
1668 * length (minus MAC) up to a multiple of the block size.
1670 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1671 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1674 (cipherblk
- (pkt
->length
+ padding
) % cipherblk
) % cipherblk
;
1675 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1676 ssh2_pkt_ensure(pkt
, pkt
->length
+ padding
+ maclen
);
1677 pkt
->data
[4] = padding
;
1678 for (i
= 0; i
< padding
; i
++)
1679 pkt
->data
[pkt
->length
+ i
] = random_byte();
1680 PUT_32BIT(pkt
->data
, pkt
->length
+ padding
- 4);
1682 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, pkt
->data
,
1683 pkt
->length
+ padding
,
1684 ssh
->v2_outgoing_sequence
);
1685 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1688 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1689 pkt
->data
, pkt
->length
+ padding
);
1691 pkt
->encrypted_len
= pkt
->length
+ padding
;
1693 /* Ready-to-send packet starts at pkt->data. We return length. */
1694 return pkt
->length
+ padding
+ maclen
;
1698 * Routines called from the main SSH code to send packets. There
1699 * are quite a few of these, because we have two separate
1700 * mechanisms for delaying the sending of packets:
1702 * - In order to send an IGNORE message and a password message in
1703 * a single fixed-length blob, we require the ability to
1704 * concatenate the encrypted forms of those two packets _into_ a
1705 * single blob and then pass it to our <network.h> transport
1706 * layer in one go. Hence, there's a deferment mechanism which
1707 * works after packet encryption.
1709 * - In order to avoid sending any connection-layer messages
1710 * during repeat key exchange, we have to queue up any such
1711 * outgoing messages _before_ they are encrypted (and in
1712 * particular before they're allocated sequence numbers), and
1713 * then send them once we've finished.
1715 * I call these mechanisms `defer' and `queue' respectively, so as
1716 * to distinguish them reasonably easily.
1718 * The functions send_noqueue() and defer_noqueue() free the packet
1719 * structure they are passed. Every outgoing packet goes through
1720 * precisely one of these functions in its life; packets passed to
1721 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1722 * these or get queued, and then when the queue is later emptied
1723 * the packets are all passed to defer_noqueue().
1727 * Send an SSH2 packet immediately, without queuing or deferring.
1729 static void ssh2_pkt_send_noqueue(Ssh ssh
, struct Packet
*pkt
)
1733 len
= ssh2_pkt_construct(ssh
, pkt
);
1734 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1735 if (backlog
> SSH_MAX_BACKLOG
)
1736 ssh_throttle_all(ssh
, 1, backlog
);
1738 ssh
->outgoing_data_size
+= pkt
->encrypted_len
;
1739 if (!ssh
->kex_in_progress
&&
1740 ssh
->max_data_size
!= 0 &&
1741 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1742 do_ssh2_transport(ssh
, "Initiating key re-exchange "
1743 "(too much data sent)", -1, NULL
);
1745 ssh_free_packet(pkt
);
1749 * Defer an SSH2 packet.
1751 static void ssh2_pkt_defer_noqueue(Ssh ssh
, struct Packet
*pkt
)
1753 int len
= ssh2_pkt_construct(ssh
, pkt
);
1754 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1755 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1756 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1760 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1761 ssh
->deferred_len
+= len
;
1762 ssh
->deferred_data_size
+= pkt
->encrypted_len
;
1763 ssh_free_packet(pkt
);
1767 * Queue an SSH2 packet.
1769 static void ssh2_pkt_queue(Ssh ssh
, struct Packet
*pkt
)
1771 assert(ssh
->queueing
);
1773 if (ssh
->queuelen
>= ssh
->queuesize
) {
1774 ssh
->queuesize
= ssh
->queuelen
+ 32;
1775 ssh
->queue
= sresize(ssh
->queue
, ssh
->queuesize
, struct Packet
*);
1778 ssh
->queue
[ssh
->queuelen
++] = pkt
;
1782 * Either queue or send a packet, depending on whether queueing is
1785 static void ssh2_pkt_send(Ssh ssh
, struct Packet
*pkt
)
1788 ssh2_pkt_queue(ssh
, pkt
);
1790 ssh2_pkt_send_noqueue(ssh
, pkt
);
1794 * Either queue or defer a packet, depending on whether queueing is
1797 static void ssh2_pkt_defer(Ssh ssh
, struct Packet
*pkt
)
1800 ssh2_pkt_queue(ssh
, pkt
);
1802 ssh2_pkt_defer_noqueue(ssh
, pkt
);
1806 * Send the whole deferred data block constructed by
1807 * ssh2_pkt_defer() or SSH1's defer_packet().
1809 * The expected use of the defer mechanism is that you call
1810 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1811 * not currently queueing, this simply sets up deferred_send_data
1812 * and then sends it. If we _are_ currently queueing, the calls to
1813 * ssh2_pkt_defer() put the deferred packets on to the queue
1814 * instead, and therefore ssh_pkt_defersend() has no deferred data
1815 * to send. Hence, there's no need to make it conditional on
1818 static void ssh_pkt_defersend(Ssh ssh
)
1821 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1823 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1824 sfree(ssh
->deferred_send_data
);
1825 ssh
->deferred_send_data
= NULL
;
1826 if (backlog
> SSH_MAX_BACKLOG
)
1827 ssh_throttle_all(ssh
, 1, backlog
);
1829 ssh
->outgoing_data_size
+= ssh
->deferred_data_size
;
1830 if (!ssh
->kex_in_progress
&&
1831 ssh
->max_data_size
!= 0 &&
1832 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1833 do_ssh2_transport(ssh
, "Initiating key re-exchange "
1834 "(too much data sent)", -1, NULL
);
1835 ssh
->deferred_data_size
= 0;
1839 * Send all queued SSH2 packets. We send them by means of
1840 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1841 * packets that needed to be lumped together.
1843 static void ssh2_pkt_queuesend(Ssh ssh
)
1847 assert(!ssh
->queueing
);
1849 for (i
= 0; i
< ssh
->queuelen
; i
++)
1850 ssh2_pkt_defer_noqueue(ssh
, ssh
->queue
[i
]);
1853 ssh_pkt_defersend(ssh
);
1857 void bndebug(char *string
, Bignum b
)
1861 p
= ssh2_mpint_fmt(b
, &len
);
1862 debug(("%s", string
));
1863 for (i
= 0; i
< len
; i
++)
1864 debug((" %02x", p
[i
]));
1870 static void sha_mpint(SHA_State
* s
, Bignum b
)
1874 p
= ssh2_mpint_fmt(b
, &len
);
1875 sha_string(s
, p
, len
);
1880 * Packet decode functions for both SSH1 and SSH2.
1882 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
)
1884 unsigned long value
;
1885 if (pkt
->length
- pkt
->savedpos
< 4)
1886 return 0; /* arrgh, no way to decline (FIXME?) */
1887 value
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1891 static int ssh2_pkt_getbool(struct Packet
*pkt
)
1893 unsigned long value
;
1894 if (pkt
->length
- pkt
->savedpos
< 1)
1895 return 0; /* arrgh, no way to decline (FIXME?) */
1896 value
= pkt
->body
[pkt
->savedpos
] != 0;
1900 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
)
1905 if (pkt
->length
- pkt
->savedpos
< 4)
1907 len
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1912 if (pkt
->length
- pkt
->savedpos
< *length
)
1914 *p
= (char *)(pkt
->body
+ pkt
->savedpos
);
1915 pkt
->savedpos
+= *length
;
1917 static void *ssh_pkt_getdata(struct Packet
*pkt
, int length
)
1919 if (pkt
->length
- pkt
->savedpos
< length
)
1921 pkt
->savedpos
+= length
;
1922 return pkt
->body
+ (pkt
->savedpos
- length
);
1924 static int ssh1_pkt_getrsakey(struct Packet
*pkt
, struct RSAKey
*key
,
1925 unsigned char **keystr
)
1929 j
= makekey(pkt
->body
+ pkt
->savedpos
,
1930 pkt
->length
- pkt
->savedpos
,
1937 assert(pkt
->savedpos
< pkt
->length
);
1941 static Bignum
ssh1_pkt_getmp(struct Packet
*pkt
)
1946 j
= ssh1_read_bignum(pkt
->body
+ pkt
->savedpos
,
1947 pkt
->length
- pkt
->savedpos
, &b
);
1955 static Bignum
ssh2_pkt_getmp(struct Packet
*pkt
)
1961 ssh_pkt_getstring(pkt
, &p
, &length
);
1966 b
= bignum_from_bytes((unsigned char *)p
, length
);
1971 * Helper function to add an SSH2 signature blob to a packet.
1972 * Expects to be shown the public key blob as well as the signature
1973 * blob. Normally works just like ssh2_pkt_addstring, but will
1974 * fiddle with the signature packet if necessary for
1975 * BUG_SSH2_RSA_PADDING.
1977 static void ssh2_add_sigblob(Ssh ssh
, struct Packet
*pkt
,
1978 void *pkblob_v
, int pkblob_len
,
1979 void *sigblob_v
, int sigblob_len
)
1981 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1982 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1984 /* dmemdump(pkblob, pkblob_len); */
1985 /* dmemdump(sigblob, sigblob_len); */
1988 * See if this is in fact an ssh-rsa signature and a buggy
1989 * server; otherwise we can just do this the easy way.
1991 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1992 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1993 int pos
, len
, siglen
;
1996 * Find the byte length of the modulus.
1999 pos
= 4+7; /* skip over "ssh-rsa" */
2000 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
2001 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
2002 pos
+= 4; /* find modulus itself */
2003 while (len
> 0 && pkblob
[pos
] == 0)
2005 /* debug(("modulus length is %d\n", len)); */
2008 * Now find the signature integer.
2010 pos
= 4+7; /* skip over "ssh-rsa" */
2011 siglen
= GET_32BIT(sigblob
+pos
);
2012 /* debug(("signature length is %d\n", siglen)); */
2014 if (len
!= siglen
) {
2015 unsigned char newlen
[4];
2016 ssh2_pkt_addstring_start(pkt
);
2017 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, pos
);
2018 /* dmemdump(sigblob, pos); */
2019 pos
+= 4; /* point to start of actual sig */
2020 PUT_32BIT(newlen
, len
);
2021 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 4);
2022 /* dmemdump(newlen, 4); */
2024 while (len
-- > siglen
) {
2025 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 1);
2026 /* dmemdump(newlen, 1); */
2028 ssh2_pkt_addstring_data(pkt
, (char *)(sigblob
+pos
), siglen
);
2029 /* dmemdump(sigblob+pos, siglen); */
2033 /* Otherwise fall through and do it the easy way. */
2036 ssh2_pkt_addstring_start(pkt
);
2037 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, sigblob_len
);
2041 * Examine the remote side's version string and compare it against
2042 * a list of known buggy implementations.
2044 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
2046 char *imp
; /* pointer to implementation part */
2048 imp
+= strcspn(imp
, "-");
2050 imp
+= strcspn(imp
, "-");
2053 ssh
->remote_bugs
= 0;
2055 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
2056 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
2057 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
2058 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
2059 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
2060 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
2062 * These versions don't support SSH1_MSG_IGNORE, so we have
2063 * to use a different defence against password length
2066 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
2067 logevent("We believe remote version has SSH1 ignore bug");
2070 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
2071 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
2072 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
2074 * These versions need a plain password sent; they can't
2075 * handle having a null and a random length of data after
2078 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
2079 logevent("We believe remote version needs a plain SSH1 password");
2082 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
2083 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
2084 (!strcmp(imp
, "Cisco-1.25")))) {
2086 * These versions apparently have no clue whatever about
2087 * RSA authentication and will panic and die if they see
2088 * an AUTH_RSA message.
2090 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
2091 logevent("We believe remote version can't handle RSA authentication");
2094 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
2095 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
2096 !wc_match("* VShell", imp
) &&
2097 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
2098 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
2099 wc_match("2.1 *", imp
)))) {
2101 * These versions have the HMAC bug.
2103 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
2104 logevent("We believe remote version has SSH2 HMAC bug");
2107 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2108 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2109 !wc_match("* VShell", imp
) &&
2110 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2112 * These versions have the key-derivation bug (failing to
2113 * include the literal shared secret in the hashes that
2114 * generate the keys).
2116 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2117 logevent("We believe remote version has SSH2 key-derivation bug");
2120 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2121 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2122 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2123 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2125 * These versions have the SSH2 RSA padding bug.
2127 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2128 logevent("We believe remote version has SSH2 RSA padding bug");
2131 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2132 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2133 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2135 * These versions have the SSH2 session-ID bug in
2136 * public-key authentication.
2138 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2139 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2144 * The `software version' part of an SSH version string is required
2145 * to contain no spaces or minus signs.
2147 static void ssh_fix_verstring(char *str
)
2149 /* Eat "SSH-<protoversion>-". */
2150 assert(*str
== 'S'); str
++;
2151 assert(*str
== 'S'); str
++;
2152 assert(*str
== 'H'); str
++;
2153 assert(*str
== '-'); str
++;
2154 while (*str
&& *str
!= '-') str
++;
2155 assert(*str
== '-'); str
++;
2157 /* Convert minus signs and spaces in the remaining string into
2160 if (*str
== '-' || *str
== ' ')
2166 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2168 struct do_ssh_init_state
{
2176 crState(do_ssh_init_state
);
2178 crBegin(ssh
->do_ssh_init_crstate
);
2180 /* Search for the string "SSH-" in the input. */
2183 static const int transS
[] = { 1, 2, 2, 1 };
2184 static const int transH
[] = { 0, 0, 3, 0 };
2185 static const int transminus
[] = { 0, 0, 0, -1 };
2187 s
->i
= transS
[s
->i
];
2189 s
->i
= transH
[s
->i
];
2191 s
->i
= transminus
[s
->i
];
2196 crReturn(1); /* get another character */
2200 s
->vstring
= snewn(s
->vstrsize
, char);
2201 strcpy(s
->vstring
, "SSH-");
2205 crReturn(1); /* get another char */
2206 if (s
->vslen
>= s
->vstrsize
- 1) {
2208 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2210 s
->vstring
[s
->vslen
++] = c
;
2213 s
->version
[s
->i
] = '\0';
2215 } else if (s
->i
< sizeof(s
->version
) - 1)
2216 s
->version
[s
->i
++] = c
;
2217 } else if (c
== '\012')
2221 ssh
->agentfwd_enabled
= FALSE
;
2222 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2224 s
->vstring
[s
->vslen
] = 0;
2225 s
->vstring
[strcspn(s
->vstring
, "\015\012")] = '\0';/* remove EOL chars */
2228 vlog
= snewn(20 + s
->vslen
, char);
2229 sprintf(vlog
, "Server version: %s", s
->vstring
);
2233 ssh_detect_bugs(ssh
, s
->vstring
);
2236 * Decide which SSH protocol version to support.
2239 /* Anything strictly below "2.0" means protocol 1 is supported. */
2240 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2241 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2242 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2244 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2245 bombout(("SSH protocol version 1 required by user but not provided by server"));
2248 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2249 bombout(("SSH protocol version 2 required by user but not provided by server"));
2256 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2258 * Construct a v2 version string.
2260 verstring
= dupprintf("SSH-2.0-%s\015\012", sshver
);
2264 * Construct a v1 version string.
2266 verstring
= dupprintf("SSH-%s-%s\012",
2267 (ssh_versioncmp(s
->version
, "1.5") <= 0 ?
2268 s
->version
: "1.5"),
2273 ssh_fix_verstring(verstring
);
2275 if (ssh
->version
== 2) {
2277 * Hash our version string and their version string.
2279 SHA_Init(&ssh
->exhashbase
);
2280 sha_string(&ssh
->exhashbase
, verstring
,
2281 strcspn(verstring
, "\015\012"));
2282 sha_string(&ssh
->exhashbase
, s
->vstring
,
2283 strcspn(s
->vstring
, "\015\012"));
2286 * Initialise SSHv2 protocol.
2288 ssh
->protocol
= ssh2_protocol
;
2289 ssh2_protocol_setup(ssh
);
2290 ssh
->s_rdpkt
= ssh2_rdpkt
;
2293 * Initialise SSHv1 protocol.
2295 ssh
->protocol
= ssh1_protocol
;
2296 ssh1_protocol_setup(ssh
);
2297 ssh
->s_rdpkt
= ssh1_rdpkt
;
2299 logeventf(ssh
, "We claim version: %.*s",
2300 strcspn(verstring
, "\015\012"), verstring
);
2301 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2305 logeventf(ssh
, "Using SSH protocol version %d", ssh
->version
);
2307 update_specials_menu(ssh
->frontend
);
2308 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2309 ssh
->pinger
= pinger_new(&ssh
->cfg
, &ssh_backend
, ssh
);
2316 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2318 crBegin(ssh
->ssh_gotdata_crstate
);
2321 * To begin with, feed the characters one by one to the
2322 * protocol initialisation / selection function do_ssh_init().
2323 * When that returns 0, we're done with the initial greeting
2324 * exchange and can move on to packet discipline.
2327 int ret
; /* need not be kept across crReturn */
2329 crReturnV
; /* more data please */
2330 ret
= do_ssh_init(ssh
, *data
);
2338 * We emerge from that loop when the initial negotiation is
2339 * over and we have selected an s_rdpkt function. Now pass
2340 * everything to s_rdpkt, and then pass the resulting packets
2341 * to the proper protocol handler.
2346 while (datalen
> 0) {
2347 struct Packet
*pktin
= ssh
->s_rdpkt(ssh
, &data
, &datalen
);
2349 ssh
->protocol(ssh
, NULL
, 0, pktin
);
2350 ssh_free_packet(pktin
);
2352 if (ssh
->state
== SSH_STATE_CLOSED
)
2360 static void ssh_do_close(Ssh ssh
)
2363 struct ssh_channel
*c
;
2365 ssh
->state
= SSH_STATE_CLOSED
;
2369 notify_remote_exit(ssh
->frontend
);
2372 * Now we must shut down any port and X forwardings going
2373 * through this connection.
2375 if (ssh
->channels
) {
2376 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2379 x11_close(c
->u
.x11
.s
);
2382 pfd_close(c
->u
.pfd
.s
);
2385 del234(ssh
->channels
, c
);
2386 if (ssh
->version
== 2)
2387 bufchain_clear(&c
->v
.v2
.outbuffer
);
2393 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2396 Ssh ssh
= (Ssh
) plug
;
2399 /* A socket error has occurred. */
2400 logevent(error_msg
);
2401 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2403 /* Otherwise, the remote side closed the connection normally. */
2408 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2410 Ssh ssh
= (Ssh
) plug
;
2411 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2412 if (ssh
->state
== SSH_STATE_CLOSED
) {
2419 static void ssh_sent(Plug plug
, int bufsize
)
2421 Ssh ssh
= (Ssh
) plug
;
2423 * If the send backlog on the SSH socket itself clears, we
2424 * should unthrottle the whole world if it was throttled.
2426 if (bufsize
< SSH_MAX_BACKLOG
)
2427 ssh_throttle_all(ssh
, 0, bufsize
);
2431 * Connect to specified host and port.
2432 * Returns an error message, or NULL on success.
2433 * Also places the canonical host name into `realhost'. It must be
2434 * freed by the caller.
2436 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2437 char **realhost
, int nodelay
, int keepalive
)
2439 static const struct plug_function_table fn_table
= {
2449 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2450 if (!ssh
->savedhost
)
2451 fatalbox("Out of memory");
2452 strcpy(ssh
->savedhost
, host
);
2455 port
= 22; /* default ssh port */
2456 ssh
->savedport
= port
;
2461 logeventf(ssh
, "Looking up host \"%s\"%s", host
,
2462 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV4 ?
" (IPv4)" :
2463 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV6 ?
" (IPv6)" : "")));
2464 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
,
2465 ssh
->cfg
.addressfamily
);
2466 if ((err
= sk_addr_error(addr
)) != NULL
) {
2476 sk_getaddr(addr
, addrbuf
, 100);
2477 logeventf(ssh
, "Connecting to %s port %d", addrbuf
, port
);
2479 ssh
->fn
= &fn_table
;
2480 ssh
->s
= new_connection(addr
, *realhost
, port
,
2481 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2482 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2484 notify_remote_exit(ssh
->frontend
);
2492 * Throttle or unthrottle the SSH connection.
2494 static void ssh1_throttle(Ssh ssh
, int adjust
)
2496 int old_count
= ssh
->v1_throttle_count
;
2497 ssh
->v1_throttle_count
+= adjust
;
2498 assert(ssh
->v1_throttle_count
>= 0);
2499 if (ssh
->v1_throttle_count
&& !old_count
) {
2500 sk_set_frozen(ssh
->s
, 1);
2501 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2502 sk_set_frozen(ssh
->s
, 0);
2507 * Throttle or unthrottle _all_ local data streams (for when sends
2508 * on the SSH connection itself back up).
2510 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2513 struct ssh_channel
*c
;
2515 if (enable
== ssh
->throttled_all
)
2517 ssh
->throttled_all
= enable
;
2518 ssh
->overall_bufsize
= bufsize
;
2521 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2523 case CHAN_MAINSESSION
:
2525 * This is treated separately, outside the switch.
2529 x11_override_throttle(c
->u
.x11
.s
, enable
);
2532 /* Agent channels require no buffer management. */
2535 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2542 * Username and password input, abstracted off into routines
2543 * reusable in several places - even between SSH1 and SSH2.
2546 /* Set up a username or password input loop on a given buffer. */
2547 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2549 ssh
->userpass_input_buffer
= buffer
;
2550 ssh
->userpass_input_buflen
= buflen
;
2551 ssh
->userpass_input_bufpos
= 0;
2552 ssh
->userpass_input_echo
= echo
;
2556 * Process some terminal data in the course of username/password
2557 * input. Returns >0 for success (line of input returned in
2558 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2559 * for inconclusive (keep waiting for more input please).
2561 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2566 switch (c
= *in
++) {
2569 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2570 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2575 if (ssh
->userpass_input_bufpos
> 0) {
2576 if (ssh
->userpass_input_echo
)
2577 c_write_str(ssh
, "\b \b");
2578 ssh
->userpass_input_bufpos
--;
2583 while (ssh
->userpass_input_bufpos
> 0) {
2584 if (ssh
->userpass_input_echo
)
2585 c_write_str(ssh
, "\b \b");
2586 ssh
->userpass_input_bufpos
--;
2595 * This simplistic check for printability is disabled
2596 * when we're doing password input, because some people
2597 * have control characters in their passwords.o
2599 if ((!ssh
->userpass_input_echo
||
2600 (c
>= ' ' && c
<= '~') ||
2601 ((unsigned char) c
>= 160))
2602 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2603 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2604 if (ssh
->userpass_input_echo
)
2605 c_write(ssh
, &c
, 1);
2613 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2615 Ssh ssh
= (Ssh
) sshv
;
2617 ssh
->agent_response
= reply
;
2618 ssh
->agent_response_len
= replylen
;
2620 if (ssh
->version
== 1)
2621 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2623 do_ssh2_authconn(ssh
, NULL
, -1, NULL
);
2626 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2628 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2630 void *sentreply
= reply
;
2633 /* Fake SSH_AGENT_FAILURE. */
2634 sentreply
= "\0\0\0\1\5";
2637 if (ssh
->version
== 2) {
2638 ssh2_add_channel_data(c
, sentreply
, replylen
);
2641 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2642 PKT_INT
, c
->remoteid
,
2645 PKT_DATA
, sentreply
, replylen
,
2654 * Handle the key exchange and user authentication phases.
2656 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
2657 struct Packet
*pktin
)
2660 unsigned char cookie
[8], *ptr
;
2661 struct RSAKey servkey
, hostkey
;
2662 struct MD5Context md5c
;
2663 struct do_ssh1_login_state
{
2665 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2666 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2667 int tried_publickey
, tried_agent
;
2668 int tis_auth_refused
, ccard_auth_refused
;
2669 unsigned char session_id
[16];
2672 void *publickey_blob
;
2673 int publickey_bloblen
;
2679 unsigned char request
[5], *response
, *p
;
2688 crState(do_ssh1_login_state
);
2690 crBegin(ssh
->do_ssh1_login_crstate
);
2695 if (pktin
->type
!= SSH1_SMSG_PUBLIC_KEY
) {
2696 bombout(("Public key packet not received"));
2700 logevent("Received public keys");
2702 ptr
= ssh_pkt_getdata(pktin
, 8);
2704 bombout(("SSH1 public key packet stopped before random cookie"));
2707 memcpy(cookie
, ptr
, 8);
2709 if (!ssh1_pkt_getrsakey(pktin
, &servkey
, &s
->keystr1
) ||
2710 !ssh1_pkt_getrsakey(pktin
, &hostkey
, &s
->keystr2
)) {
2711 bombout(("Failed to read SSH1 public keys from public key packet"));
2716 * Log the host key fingerprint.
2720 logevent("Host key fingerprint is:");
2721 strcpy(logmsg
, " ");
2722 hostkey
.comment
= NULL
;
2723 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2724 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2728 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(pktin
);
2729 s
->supported_ciphers_mask
= ssh_pkt_getuint32(pktin
);
2730 s
->supported_auths_mask
= ssh_pkt_getuint32(pktin
);
2732 ssh
->v1_local_protoflags
=
2733 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2734 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2737 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2738 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2739 MD5Update(&md5c
, cookie
, 8);
2740 MD5Final(s
->session_id
, &md5c
);
2742 for (i
= 0; i
< 32; i
++)
2743 ssh
->session_key
[i
] = random_byte();
2746 * Verify that the `bits' and `bytes' parameters match.
2748 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
2749 servkey
.bits
> servkey
.bytes
* 8) {
2750 bombout(("SSH1 public keys were badly formatted"));
2754 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2756 s
->rsabuf
= snewn(s
->len
, unsigned char);
2758 fatalbox("Out of memory");
2761 * Verify the host key.
2765 * First format the key into a string.
2767 int len
= rsastr_len(&hostkey
);
2768 char fingerprint
[100];
2769 char *keystr
= snewn(len
, char);
2771 fatalbox("Out of memory");
2772 rsastr_fmt(keystr
, &hostkey
);
2773 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2774 verify_ssh_host_key(ssh
->frontend
,
2775 ssh
->savedhost
, ssh
->savedport
, "rsa", keystr
,
2780 for (i
= 0; i
< 32; i
++) {
2781 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2783 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2786 if (hostkey
.bytes
> servkey
.bytes
) {
2787 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
2789 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2791 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2793 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2796 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2800 logevent("Encrypted session key");
2803 int cipher_chosen
= 0, warn
= 0;
2804 char *cipher_string
= NULL
;
2806 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2807 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
2808 if (next_cipher
== CIPHER_WARN
) {
2809 /* If/when we choose a cipher, warn about it */
2811 } else if (next_cipher
== CIPHER_AES
) {
2812 /* XXX Probably don't need to mention this. */
2813 logevent("AES not supported in SSH1, skipping");
2815 switch (next_cipher
) {
2816 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2817 cipher_string
= "3DES"; break;
2818 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2819 cipher_string
= "Blowfish"; break;
2820 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2821 cipher_string
= "single-DES"; break;
2823 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2827 if (!cipher_chosen
) {
2828 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2829 bombout(("Server violates SSH 1 protocol by not "
2830 "supporting 3DES encryption"));
2832 /* shouldn't happen */
2833 bombout(("No supported ciphers found"));
2837 /* Warn about chosen cipher if necessary. */
2839 sk_set_frozen(ssh
->s
, 1);
2840 askalg(ssh
->frontend
, "cipher", cipher_string
);
2841 sk_set_frozen(ssh
->s
, 0);
2845 switch (s
->cipher_type
) {
2846 case SSH_CIPHER_3DES
:
2847 logevent("Using 3DES encryption");
2849 case SSH_CIPHER_DES
:
2850 logevent("Using single-DES encryption");
2852 case SSH_CIPHER_BLOWFISH
:
2853 logevent("Using Blowfish encryption");
2857 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
2858 PKT_CHAR
, s
->cipher_type
,
2859 PKT_DATA
, cookie
, 8,
2860 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
2861 PKT_DATA
, s
->rsabuf
, s
->len
,
2862 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
2864 logevent("Trying to enable encryption...");
2868 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2869 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
2871 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
2872 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
2873 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
2875 ssh
->crcda_ctx
= crcda_make_context();
2876 logevent("Installing CRC compensation attack detector");
2878 if (servkey
.modulus
) {
2879 sfree(servkey
.modulus
);
2880 servkey
.modulus
= NULL
;
2882 if (servkey
.exponent
) {
2883 sfree(servkey
.exponent
);
2884 servkey
.exponent
= NULL
;
2886 if (hostkey
.modulus
) {
2887 sfree(hostkey
.modulus
);
2888 hostkey
.modulus
= NULL
;
2890 if (hostkey
.exponent
) {
2891 sfree(hostkey
.exponent
);
2892 hostkey
.exponent
= NULL
;
2896 if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
2897 bombout(("Encryption not successfully enabled"));
2901 logevent("Successfully started encryption");
2905 if (!*ssh
->cfg
.username
) {
2906 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2907 if (!ssh_get_line("login as: ",
2908 s
->username
, sizeof(s
->username
), FALSE
)) {
2910 * get_line failed to get a username.
2913 logevent("No username provided. Abandoning session.");
2914 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2918 int ret
; /* need not be kept over crReturn */
2919 c_write_str(ssh
, "login as: ");
2922 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
2924 crWaitUntil(!pktin
);
2925 ret
= process_userpass_input(ssh
, in
, inlen
);
2929 c_write_str(ssh
, "\r\n");
2932 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
2933 s
->username
[sizeof(s
->username
)-1] = '\0';
2936 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
2938 char userlog
[22 + sizeof(s
->username
)];
2939 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
2941 if (flags
& FLAG_INTERACTIVE
&&
2942 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2943 strcat(userlog
, "\r\n");
2944 c_write_str(ssh
, userlog
);
2951 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2952 /* We must not attempt PK auth. Pretend we've already tried it. */
2953 s
->tried_publickey
= s
->tried_agent
= 1;
2955 s
->tried_publickey
= s
->tried_agent
= 0;
2957 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
2958 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
2959 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
2960 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
2961 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
2962 s
->publickey_blob
= NULL
;
2964 s
->publickey_blob
= NULL
;
2966 while (pktin
->type
== SSH1_SMSG_FAILURE
) {
2967 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2969 if (agent_exists() && !s
->tried_agent
) {
2971 * Attempt RSA authentication using Pageant.
2977 logevent("Pageant is running. Requesting keys.");
2979 /* Request the keys held by the agent. */
2980 PUT_32BIT(s
->request
, 1);
2981 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2982 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
2983 ssh_agent_callback
, ssh
)) {
2987 bombout(("Unexpected data from server while waiting"
2988 " for agent response"));
2991 } while (pktin
|| inlen
> 0);
2992 r
= ssh
->agent_response
;
2993 s
->responselen
= ssh
->agent_response_len
;
2995 s
->response
= (unsigned char *) r
;
2996 if (s
->response
&& s
->responselen
>= 5 &&
2997 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
2998 s
->p
= s
->response
+ 5;
2999 s
->nkeys
= GET_32BIT(s
->p
);
3003 sprintf(buf
, "Pageant has %d SSH1 keys", s
->nkeys
);
3006 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
3009 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
3012 if (s
->publickey_blob
&&
3013 !memcmp(s
->p
, s
->publickey_blob
,
3014 s
->publickey_bloblen
)) {
3015 logevent("This key matches configured key file");
3016 s
->tried_publickey
= 1;
3021 do { /* do while (0) to make breaking easy */
3022 n
= ssh1_read_bignum
3023 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3028 n
= ssh1_read_bignum
3029 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3034 if (s
->responselen
- (s
->p
-s
->response
) < 4)
3036 s
->commentlen
= GET_32BIT(s
->p
);
3038 if (s
->responselen
- (s
->p
-s
->response
) <
3041 s
->commentp
= (char *)s
->p
;
3042 s
->p
+= s
->commentlen
;
3046 logevent("Pageant key list packet was truncated");
3050 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3051 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3053 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3054 logevent("Key refused");
3057 logevent("Received RSA challenge");
3058 if ((s
->challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3059 bombout(("Server's RSA challenge was badly formatted"));
3064 char *agentreq
, *q
, *ret
;
3067 len
= 1 + 4; /* message type, bit count */
3068 len
+= ssh1_bignum_length(s
->key
.exponent
);
3069 len
+= ssh1_bignum_length(s
->key
.modulus
);
3070 len
+= ssh1_bignum_length(s
->challenge
);
3071 len
+= 16; /* session id */
3072 len
+= 4; /* response format */
3073 agentreq
= snewn(4 + len
, char);
3074 PUT_32BIT(agentreq
, len
);
3076 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
3077 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
3079 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
3080 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
3081 q
+= ssh1_write_bignum(q
, s
->challenge
);
3082 memcpy(q
, s
->session_id
, 16);
3084 PUT_32BIT(q
, 1); /* response format */
3085 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
3086 ssh_agent_callback
, ssh
)) {
3091 bombout(("Unexpected data from server"
3092 " while waiting for agent"
3096 } while (pktin
|| inlen
> 0);
3097 vret
= ssh
->agent_response
;
3098 retlen
= ssh
->agent_response_len
;
3103 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
3104 logevent("Sending Pageant's response");
3105 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3106 PKT_DATA
, ret
+ 5, 16,
3110 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
3112 ("Pageant's response accepted");
3113 if (flags
& FLAG_VERBOSE
) {
3114 c_write_str(ssh
, "Authenticated using"
3116 c_write(ssh
, s
->commentp
,
3118 c_write_str(ssh
, "\" from agent\r\n");
3123 ("Pageant's response not accepted");
3126 ("Pageant failed to answer challenge");
3130 logevent("No reply received from Pageant");
3133 freebn(s
->key
.exponent
);
3134 freebn(s
->key
.modulus
);
3135 freebn(s
->challenge
);
3144 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
3145 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
3147 if (ssh
->cfg
.try_tis_auth
&&
3148 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3149 !s
->tis_auth_refused
) {
3150 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3151 logevent("Requested TIS authentication");
3152 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3154 if (pktin
->type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3155 logevent("TIS authentication declined");
3156 if (flags
& FLAG_INTERACTIVE
)
3157 c_write_str(ssh
, "TIS authentication refused.\r\n");
3158 s
->tis_auth_refused
= 1;
3164 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3166 bombout(("TIS challenge packet was badly formed"));
3169 logevent("Received TIS challenge");
3170 if (challengelen
> sizeof(s
->prompt
) - 1)
3171 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3172 memcpy(s
->prompt
, challenge
, challengelen
);
3173 /* Prompt heuristic comes from OpenSSH */
3174 strncpy(s
->prompt
+ challengelen
,
3175 memchr(s
->prompt
, '\n', challengelen
) ?
3176 "": "\r\nResponse: ",
3177 (sizeof s
->prompt
) - challengelen
);
3178 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
3181 if (ssh
->cfg
.try_tis_auth
&&
3182 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3183 !s
->ccard_auth_refused
) {
3184 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3185 logevent("Requested CryptoCard authentication");
3186 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3188 if (pktin
->type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3189 logevent("CryptoCard authentication declined");
3190 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3191 s
->ccard_auth_refused
= 1;
3197 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3199 bombout(("CryptoCard challenge packet was badly formed"));
3202 logevent("Received CryptoCard challenge");
3203 if (challengelen
> sizeof(s
->prompt
) - 1)
3204 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3205 memcpy(s
->prompt
, challenge
, challengelen
);
3206 strncpy(s
->prompt
+ challengelen
,
3207 memchr(s
->prompt
, '\n', challengelen
) ?
3208 "" : "\r\nResponse: ",
3209 sizeof(s
->prompt
) - challengelen
);
3210 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
3213 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3214 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
3215 s
->username
, ssh
->savedhost
);
3217 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3218 char *comment
= NULL
;
3221 if (flags
& FLAG_VERBOSE
)
3222 c_write_str(ssh
, "Trying public key authentication.\r\n");
3223 logeventf(ssh
, "Trying public key \"%s\"",
3224 filename_to_str(&ssh
->cfg
.keyfile
));
3225 type
= key_type(&ssh
->cfg
.keyfile
);
3226 if (type
!= SSH_KEYTYPE_SSH1
) {
3227 sprintf(msgbuf
, "Key is of wrong type (%s)",
3228 key_type_to_str(type
));
3230 c_write_str(ssh
, msgbuf
);
3231 c_write_str(ssh
, "\r\n");
3232 s
->tried_publickey
= 1;
3235 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
3236 if (flags
& FLAG_VERBOSE
)
3237 c_write_str(ssh
, "No passphrase required.\r\n");
3240 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
3245 * Show password prompt, having first obtained it via a TIS
3246 * or CryptoCard exchange if we're doing TIS or CryptoCard
3250 if (!ssh_get_line(s
->prompt
, s
->password
,
3251 sizeof(s
->password
), TRUE
)) {
3253 * get_line failed to get a password (for example
3254 * because one was supplied on the command line
3255 * which has already failed to work). Terminate.
3257 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
3258 PKT_STR
, "No more passwords available to try",
3260 logevent("Unable to authenticate");
3261 connection_fatal(ssh
->frontend
, "Unable to authenticate");
3262 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3266 /* Prompt may have come from server. We've munged it a bit, so
3267 * we know it to be zero-terminated at least once. */
3268 int ret
; /* need not be saved over crReturn */
3269 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3272 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3274 crWaitUntil(!pktin
);
3275 ret
= process_userpass_input(ssh
, in
, inlen
);
3279 c_write_str(ssh
, "\r\n");
3283 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3285 * Try public key authentication with the specified
3288 s
->tried_publickey
= 1;
3291 const char *error
= NULL
;
3292 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3295 c_write_str(ssh
, "Couldn't load private key from ");
3296 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3297 c_write_str(ssh
, " (");
3298 c_write_str(ssh
, error
);
3299 c_write_str(ssh
, ").\r\n");
3300 continue; /* go and try password */
3303 c_write_str(ssh
, "Wrong passphrase.\r\n");
3304 s
->tried_publickey
= 0;
3305 continue; /* try again */
3310 * Send a public key attempt.
3312 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3313 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3316 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3317 c_write_str(ssh
, "Server refused our public key.\r\n");
3318 continue; /* go and try password */
3320 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3321 bombout(("Bizarre response to offer of public key"));
3327 unsigned char buffer
[32];
3328 Bignum challenge
, response
;
3330 if ((challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3331 bombout(("Server's RSA challenge was badly formatted"));
3334 response
= rsadecrypt(challenge
, &s
->key
);
3335 freebn(s
->key
.private_exponent
);/* burn the evidence */
3337 for (i
= 0; i
< 32; i
++) {
3338 buffer
[i
] = bignum_byte(response
, 31 - i
);
3342 MD5Update(&md5c
, buffer
, 32);
3343 MD5Update(&md5c
, s
->session_id
, 16);
3344 MD5Final(buffer
, &md5c
);
3346 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3347 PKT_DATA
, buffer
, 16, PKT_END
);
3354 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3355 if (flags
& FLAG_VERBOSE
)
3356 c_write_str(ssh
, "Failed to authenticate with"
3357 " our public key.\r\n");
3358 continue; /* go and try password */
3359 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3360 bombout(("Bizarre response to RSA authentication response"));
3364 break; /* we're through! */
3366 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3368 * Defence against traffic analysis: we send a
3369 * whole bunch of packets containing strings of
3370 * different lengths. One of these strings is the
3371 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3372 * The others are all random data in
3373 * SSH1_MSG_IGNORE packets. This way a passive
3374 * listener can't tell which is the password, and
3375 * hence can't deduce the password length.
3377 * Anybody with a password length greater than 16
3378 * bytes is going to have enough entropy in their
3379 * password that a listener won't find it _that_
3380 * much help to know how long it is. So what we'll
3383 * - if password length < 16, we send 15 packets
3384 * containing string lengths 1 through 15
3386 * - otherwise, we let N be the nearest multiple
3387 * of 8 below the password length, and send 8
3388 * packets containing string lengths N through
3389 * N+7. This won't obscure the order of
3390 * magnitude of the password length, but it will
3391 * introduce a bit of extra uncertainty.
3393 * A few servers (the old 1.2.18 through 1.2.22)
3394 * can't deal with SSH1_MSG_IGNORE. For these
3395 * servers, we need an alternative defence. We make
3396 * use of the fact that the password is interpreted
3397 * as a C string: so we can append a NUL, then some
3400 * One server (a Cisco one) can deal with neither
3401 * SSH1_MSG_IGNORE _nor_ a padded password string.
3402 * For this server we are left with no defences
3403 * against password length sniffing.
3405 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3407 * The server can deal with SSH1_MSG_IGNORE, so
3408 * we can use the primary defence.
3410 int bottom
, top
, pwlen
, i
;
3413 pwlen
= strlen(s
->password
);
3415 bottom
= 0; /* zero length passwords are OK! :-) */
3418 bottom
= pwlen
& ~7;
3422 assert(pwlen
>= bottom
&& pwlen
<= top
);
3424 randomstr
= snewn(top
+ 1, char);
3426 for (i
= bottom
; i
<= top
; i
++) {
3428 defer_packet(ssh
, s
->pwpkt_type
,
3429 PKTT_PASSWORD
, PKT_STR
, s
->password
,
3430 PKTT_OTHER
, PKT_END
);
3432 for (j
= 0; j
< i
; j
++) {
3434 randomstr
[j
] = random_byte();
3435 } while (randomstr
[j
] == '\0');
3437 randomstr
[i
] = '\0';
3438 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3439 PKT_STR
, randomstr
, PKT_END
);
3442 logevent("Sending password with camouflage packets");
3443 ssh_pkt_defersend(ssh
);
3446 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3448 * The server can't deal with SSH1_MSG_IGNORE
3449 * but can deal with padded passwords, so we
3450 * can use the secondary defence.
3456 len
= strlen(s
->password
);
3457 if (len
< sizeof(string
)) {
3459 strcpy(string
, s
->password
);
3460 len
++; /* cover the zero byte */
3461 while (len
< sizeof(string
)) {
3462 string
[len
++] = (char) random_byte();
3467 logevent("Sending length-padded password");
3468 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3469 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3470 PKTT_OTHER
, PKT_END
);
3473 * The server has _both_
3474 * BUG_CHOKES_ON_SSH1_IGNORE and
3475 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3476 * therefore nothing we can do.
3479 len
= strlen(s
->password
);
3480 logevent("Sending unpadded password");
3481 send_packet(ssh
, s
->pwpkt_type
,
3482 PKTT_PASSWORD
, PKT_INT
, len
,
3483 PKT_DATA
, s
->password
, len
,
3484 PKTT_OTHER
, PKT_END
);
3487 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3488 PKT_STR
, s
->password
, PKTT_OTHER
, PKT_END
);
3491 logevent("Sent password");
3492 memset(s
->password
, 0, strlen(s
->password
));
3494 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3495 if (flags
& FLAG_VERBOSE
)
3496 c_write_str(ssh
, "Access denied\r\n");
3497 logevent("Authentication refused");
3498 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3499 bombout(("Strange packet received, type %d", pktin
->type
));
3504 logevent("Authentication successful");
3509 void sshfwd_close(struct ssh_channel
*c
)
3513 if (ssh
->state
!= SSH_STATE_SESSION
) {
3514 assert(ssh
->state
== SSH_STATE_CLOSED
);
3518 if (c
&& !c
->closes
) {
3520 * If the channel's remoteid is -1, we have sent
3521 * CHANNEL_OPEN for this channel, but it hasn't even been
3522 * acknowledged by the server. So we must set a close flag
3523 * on it now, and then when the server acks the channel
3524 * open, we can close it then.
3526 if (((int)c
->remoteid
) != -1) {
3527 if (ssh
->version
== 1) {
3528 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3531 struct Packet
*pktout
;
3532 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3533 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
3534 ssh2_pkt_send(ssh
, pktout
);
3537 c
->closes
= 1; /* sent MSG_CLOSE */
3538 if (c
->type
== CHAN_X11
) {
3540 logevent("Forwarded X11 connection terminated");
3541 } else if (c
->type
== CHAN_SOCKDATA
||
3542 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3544 logevent("Forwarded port closed");
3549 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3553 if (ssh
->state
!= SSH_STATE_SESSION
) {
3554 assert(ssh
->state
== SSH_STATE_CLOSED
);
3558 if (ssh
->version
== 1) {
3559 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3560 PKT_INT
, c
->remoteid
,
3562 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3563 PKTT_OTHER
, PKT_END
);
3565 * In SSH1 we can return 0 here - implying that forwarded
3566 * connections are never individually throttled - because
3567 * the only circumstance that can cause throttling will be
3568 * the whole SSH connection backing up, in which case
3569 * _everything_ will be throttled as a whole.
3573 ssh2_add_channel_data(c
, buf
, len
);
3574 return ssh2_try_send(c
);
3578 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3582 if (ssh
->state
!= SSH_STATE_SESSION
) {
3583 assert(ssh
->state
== SSH_STATE_CLOSED
);
3587 if (ssh
->version
== 1) {
3588 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3589 c
->v
.v1
.throttling
= 0;
3590 ssh1_throttle(ssh
, -1);
3593 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3597 static void ssh_queueing_handler(Ssh ssh
, struct Packet
*pktin
)
3599 struct queued_handler
*qh
= ssh
->qhead
;
3603 assert(pktin
->type
== qh
->msg1
|| pktin
->type
== qh
->msg2
);
3606 assert(ssh
->packet_dispatch
[qh
->msg1
] == ssh_queueing_handler
);
3607 ssh
->packet_dispatch
[qh
->msg1
] = NULL
;
3610 assert(ssh
->packet_dispatch
[qh
->msg2
] == ssh_queueing_handler
);
3611 ssh
->packet_dispatch
[qh
->msg2
] = NULL
;
3615 ssh
->qhead
= qh
->next
;
3617 if (ssh
->qhead
->msg1
> 0) {
3618 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg1
] == NULL
);
3619 ssh
->packet_dispatch
[ssh
->qhead
->msg1
] = ssh_queueing_handler
;
3621 if (ssh
->qhead
->msg2
> 0) {
3622 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg2
] == NULL
);
3623 ssh
->packet_dispatch
[ssh
->qhead
->msg2
] = ssh_queueing_handler
;
3626 ssh
->qhead
= ssh
->qtail
= NULL
;
3627 ssh
->packet_dispatch
[pktin
->type
] = NULL
;
3630 qh
->handler(ssh
, pktin
, qh
->ctx
);
3635 static void ssh_queue_handler(Ssh ssh
, int msg1
, int msg2
,
3636 chandler_fn_t handler
, void *ctx
)
3638 struct queued_handler
*qh
;
3640 qh
= snew(struct queued_handler
);
3643 qh
->handler
= handler
;
3647 if (ssh
->qtail
== NULL
) {
3651 assert(ssh
->packet_dispatch
[qh
->msg1
] == NULL
);
3652 ssh
->packet_dispatch
[qh
->msg1
] = ssh_queueing_handler
;
3655 assert(ssh
->packet_dispatch
[qh
->msg2
] == NULL
);
3656 ssh
->packet_dispatch
[qh
->msg2
] = ssh_queueing_handler
;
3659 ssh
->qtail
->next
= qh
;
3664 static void ssh_rportfwd_succfail(Ssh ssh
, struct Packet
*pktin
, void *ctx
)
3666 struct ssh_rportfwd
*rpf
, *pf
= (struct ssh_rportfwd
*)ctx
;
3668 if (pktin
->type
== (ssh
->version
== 1 ? SSH1_SMSG_SUCCESS
:
3669 SSH2_MSG_REQUEST_SUCCESS
)) {
3670 logeventf(ssh
, "Remote port forwarding from %s enabled",
3673 logeventf(ssh
, "Remote port forwarding from %s refused",
3676 rpf
= del234(ssh
->rportfwds
, pf
);
3682 static void ssh_setup_portfwd(Ssh ssh
, const Config
*cfg
)
3684 const char *portfwd_strptr
= cfg
->portfwd
;
3685 struct ssh_portfwd
*epf
;
3688 if (!ssh
->portfwds
) {
3689 ssh
->portfwds
= newtree234(ssh_portcmp
);
3692 * Go through the existing port forwardings and tag them
3693 * with status==DESTROY. Any that we want to keep will be
3694 * re-enabled (status==KEEP) as we go through the
3695 * configuration and find out which bits are the same as
3698 struct ssh_portfwd
*epf
;
3700 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3701 epf
->status
= DESTROY
;
3704 while (*portfwd_strptr
) {
3705 char address_family
, type
;
3706 int sport
,dport
,sserv
,dserv
;
3707 char sports
[256], dports
[256], saddr
[256], host
[256];
3710 address_family
= 'A';
3712 if (*portfwd_strptr
== 'A' ||
3713 *portfwd_strptr
== '4' ||
3714 *portfwd_strptr
== '6')
3715 address_family
= *portfwd_strptr
++;
3716 if (*portfwd_strptr
== 'L' ||
3717 *portfwd_strptr
== 'R' ||
3718 *portfwd_strptr
== 'D')
3719 type
= *portfwd_strptr
++;
3724 while (*portfwd_strptr
&& *portfwd_strptr
!= '\t') {
3725 if (*portfwd_strptr
== ':') {
3727 * We've seen a colon in the middle of the
3728 * source port number. This means that
3729 * everything we've seen until now is the
3730 * source _address_, so we'll move it into
3731 * saddr and start sports from the beginning
3736 if (ssh
->version
== 1 && type
== 'R') {
3737 logeventf(ssh
, "SSH1 cannot handle remote source address "
3738 "spec \"%s\"; ignoring", sports
);
3740 strcpy(saddr
, sports
);
3743 if (n
< 255) sports
[n
++] = *portfwd_strptr
++;
3747 if (*portfwd_strptr
== '\t')
3750 while (*portfwd_strptr
&& *portfwd_strptr
!= ':') {
3751 if (n
< 255) host
[n
++] = *portfwd_strptr
++;
3754 if (*portfwd_strptr
== ':')
3757 while (*portfwd_strptr
) {
3758 if (n
< 255) dports
[n
++] = *portfwd_strptr
++;
3762 dport
= atoi(dports
);
3766 dport
= net_service_lookup(dports
);
3768 logeventf(ssh
, "Service lookup failed for destination"
3769 " port \"%s\"", dports
);
3773 while (*portfwd_strptr
) portfwd_strptr
++;
3775 portfwd_strptr
++; /* eat the NUL and move to next one */
3777 sport
= atoi(sports
);
3781 sport
= net_service_lookup(sports
);
3783 logeventf(ssh
, "Service lookup failed for source"
3784 " port \"%s\"", sports
);
3787 if (sport
&& dport
) {
3788 /* Set up a description of the source port. */
3789 struct ssh_portfwd
*pfrec
, *epfrec
;
3791 pfrec
= snew(struct ssh_portfwd
);
3793 pfrec
->saddr
= *saddr ?
dupstr(saddr
) : NULL
;
3794 pfrec
->sserv
= sserv ?
dupstr(sports
) : NULL
;
3795 pfrec
->sport
= sport
;
3796 pfrec
->daddr
= *host ?
dupstr(host
) : NULL
;
3797 pfrec
->dserv
= dserv ?
dupstr(dports
) : NULL
;
3798 pfrec
->dport
= dport
;
3799 pfrec
->local
= NULL
;
3800 pfrec
->remote
= NULL
;
3801 pfrec
->addressfamily
= (address_family
== '4' ? ADDRTYPE_IPV4
:
3802 address_family
== '6' ? ADDRTYPE_IPV6
:
3805 epfrec
= add234(ssh
->portfwds
, pfrec
);
3806 if (epfrec
!= pfrec
) {
3808 * We already have a port forwarding with precisely
3809 * these parameters. Hence, no need to do anything;
3810 * simply tag the existing one as KEEP.
3812 epfrec
->status
= KEEP
;
3813 free_portfwd(pfrec
);
3815 pfrec
->status
= CREATE
;
3821 * Now go through and destroy any port forwardings which were
3824 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3825 if (epf
->status
== DESTROY
) {
3828 message
= dupprintf("%s port forwarding from %s%s%d",
3829 epf
->type
== 'L' ?
"local" :
3830 epf
->type
== 'R' ?
"remote" : "dynamic",
3831 epf
->saddr ? epf
->saddr
: "",
3832 epf
->saddr ?
":" : "",
3835 if (epf
->type
!= 'D') {
3836 char *msg2
= dupprintf("%s to %s:%d", message
,
3837 epf
->daddr
, epf
->dport
);
3842 logeventf(ssh
, "Cancelling %s", message
);
3846 struct ssh_rportfwd
*rpf
= epf
->remote
;
3847 struct Packet
*pktout
;
3850 * Cancel the port forwarding at the server
3853 if (ssh
->version
== 1) {
3855 * We cannot cancel listening ports on the
3856 * server side in SSH1! There's no message
3857 * to support it. Instead, we simply remove
3858 * the rportfwd record from the local end
3859 * so that any connections the server tries
3860 * to make on it are rejected.
3863 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
3864 ssh2_pkt_addstring(pktout
, "cancel-tcpip-forward");
3865 ssh2_pkt_addbool(pktout
, 0);/* _don't_ want reply */
3867 ssh2_pkt_addstring(pktout
, epf
->saddr
);
3868 } else if (ssh
->cfg
.rport_acceptall
) {
3869 ssh2_pkt_addstring(pktout
, "0.0.0.0");
3871 ssh2_pkt_addstring(pktout
, "127.0.0.1");
3873 ssh2_pkt_adduint32(pktout
, epf
->sport
);
3874 ssh2_pkt_send(ssh
, pktout
);
3877 del234(ssh
->rportfwds
, rpf
);
3879 } else if (epf
->local
) {
3880 pfd_terminate(epf
->local
);
3883 delpos234(ssh
->portfwds
, i
);
3885 i
--; /* so we don't skip one in the list */
3889 * And finally, set up any new port forwardings (status==CREATE).
3891 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3892 if (epf
->status
== CREATE
) {
3893 char *sportdesc
, *dportdesc
;
3894 sportdesc
= dupprintf("%s%s%s%s%d%s",
3895 epf
->saddr ? epf
->saddr
: "",
3896 epf
->saddr ?
":" : "",
3897 epf
->sserv ? epf
->sserv
: "",
3898 epf
->sserv ?
"(" : "",
3900 epf
->sserv ?
")" : "");
3901 if (epf
->type
== 'D') {
3904 dportdesc
= dupprintf("%s:%s%s%d%s",
3906 epf
->dserv ? epf
->dserv
: "",
3907 epf
->dserv ?
"(" : "",
3909 epf
->dserv ?
")" : "");
3912 if (epf
->type
== 'L') {
3913 const char *err
= pfd_addforward(epf
->daddr
, epf
->dport
,
3914 epf
->saddr
, epf
->sport
,
3917 epf
->addressfamily
);
3919 logeventf(ssh
, "Local %sport %s forwarding to %s%s%s",
3920 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
3921 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
3922 sportdesc
, dportdesc
,
3923 err ?
" failed: " : "", err ? err
: "");
3924 } else if (epf
->type
== 'D') {
3925 const char *err
= pfd_addforward(NULL
, -1,
3926 epf
->saddr
, epf
->sport
,
3929 epf
->addressfamily
);
3931 logeventf(ssh
, "Local %sport %s SOCKS dynamic forwarding%s%s",
3932 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
3933 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
3935 err ?
" failed: " : "", err ? err
: "");
3937 struct ssh_rportfwd
*pf
;
3940 * Ensure the remote port forwardings tree exists.
3942 if (!ssh
->rportfwds
) {
3943 if (ssh
->version
== 1)
3944 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3946 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
3949 pf
= snew(struct ssh_rportfwd
);
3950 strncpy(pf
->dhost
, epf
->daddr
, lenof(pf
->dhost
)-1);
3951 pf
->dhost
[lenof(pf
->dhost
)-1] = '\0';
3952 pf
->dport
= epf
->dport
;
3953 pf
->sport
= epf
->sport
;
3954 if (add234(ssh
->rportfwds
, pf
) != pf
) {
3955 logeventf(ssh
, "Duplicate remote port forwarding to %s:%d",
3956 epf
->daddr
, epf
->dport
);
3959 logeventf(ssh
, "Requesting remote port %s"
3960 " forward to %s", sportdesc
, dportdesc
);
3962 pf
->sportdesc
= sportdesc
;
3967 if (ssh
->version
== 1) {
3968 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
3969 PKT_INT
, epf
->sport
,
3970 PKT_STR
, epf
->daddr
,
3971 PKT_INT
, epf
->dport
,
3973 ssh_queue_handler(ssh
, SSH1_SMSG_SUCCESS
,
3975 ssh_rportfwd_succfail
, pf
);
3977 struct Packet
*pktout
;
3978 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
3979 ssh2_pkt_addstring(pktout
, "tcpip-forward");
3980 ssh2_pkt_addbool(pktout
, 1);/* want reply */
3982 ssh2_pkt_addstring(pktout
, epf
->saddr
);
3983 } else if (ssh
->cfg
.rport_acceptall
) {
3984 ssh2_pkt_addstring(pktout
, "0.0.0.0");
3986 ssh2_pkt_addstring(pktout
, "127.0.0.1");
3988 ssh2_pkt_adduint32(pktout
, epf
->sport
);
3989 ssh2_pkt_send(ssh
, pktout
);
3991 ssh_queue_handler(ssh
, SSH2_MSG_REQUEST_SUCCESS
,
3992 SSH2_MSG_REQUEST_FAILURE
,
3993 ssh_rportfwd_succfail
, pf
);
4002 static void ssh1_smsg_stdout_stderr_data(Ssh ssh
, struct Packet
*pktin
)
4005 int stringlen
, bufsize
;
4007 ssh_pkt_getstring(pktin
, &string
, &stringlen
);
4008 if (string
== NULL
) {
4009 bombout(("Incoming terminal data packet was badly formed"));
4013 bufsize
= from_backend(ssh
->frontend
, pktin
->type
== SSH1_SMSG_STDERR_DATA
,
4015 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4016 ssh
->v1_stdout_throttling
= 1;
4017 ssh1_throttle(ssh
, +1);
4021 static void ssh1_smsg_x11_open(Ssh ssh
, struct Packet
*pktin
)
4023 /* Remote side is trying to open a channel to talk to our
4024 * X-Server. Give them back a local channel number. */
4025 struct ssh_channel
*c
;
4026 int remoteid
= ssh_pkt_getuint32(pktin
);
4028 logevent("Received X11 connect request");
4029 /* Refuse if X11 forwarding is disabled. */
4030 if (!ssh
->X11_fwd_enabled
) {
4031 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4032 PKT_INT
, remoteid
, PKT_END
);
4033 logevent("Rejected X11 connect request");
4035 c
= snew(struct ssh_channel
);
4038 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
4039 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
4040 logevent("Opening X11 forward connection failed");
4042 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4043 PKT_INT
, remoteid
, PKT_END
);
4046 ("Opening X11 forward connection succeeded");
4047 c
->remoteid
= remoteid
;
4048 c
->localid
= alloc_channel_id(ssh
);
4050 c
->v
.v1
.throttling
= 0;
4051 c
->type
= CHAN_X11
; /* identify channel type */
4052 add234(ssh
->channels
, c
);
4053 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4054 PKT_INT
, c
->remoteid
, PKT_INT
,
4055 c
->localid
, PKT_END
);
4056 logevent("Opened X11 forward channel");
4061 static void ssh1_smsg_agent_open(Ssh ssh
, struct Packet
*pktin
)
4063 /* Remote side is trying to open a channel to talk to our
4064 * agent. Give them back a local channel number. */
4065 struct ssh_channel
*c
;
4066 int remoteid
= ssh_pkt_getuint32(pktin
);
4068 /* Refuse if agent forwarding is disabled. */
4069 if (!ssh
->agentfwd_enabled
) {
4070 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4071 PKT_INT
, remoteid
, PKT_END
);
4073 c
= snew(struct ssh_channel
);
4075 c
->remoteid
= remoteid
;
4076 c
->localid
= alloc_channel_id(ssh
);
4078 c
->v
.v1
.throttling
= 0;
4079 c
->type
= CHAN_AGENT
; /* identify channel type */
4080 c
->u
.a
.lensofar
= 0;
4081 add234(ssh
->channels
, c
);
4082 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4083 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
4088 static void ssh1_msg_port_open(Ssh ssh
, struct Packet
*pktin
)
4090 /* Remote side is trying to open a channel to talk to a
4091 * forwarded port. Give them back a local channel number. */
4092 struct ssh_channel
*c
;
4093 struct ssh_rportfwd pf
, *pfp
;
4096 char *host
, buf
[1024];
4098 c
= snew(struct ssh_channel
);
4101 remoteid
= ssh_pkt_getuint32(pktin
);
4102 ssh_pkt_getstring(pktin
, &host
, &hostsize
);
4103 port
= ssh_pkt_getuint32(pktin
);
4105 if (hostsize
>= lenof(pf
.dhost
))
4106 hostsize
= lenof(pf
.dhost
)-1;
4107 memcpy(pf
.dhost
, host
, hostsize
);
4108 pf
.dhost
[hostsize
] = '\0';
4110 pfp
= find234(ssh
->rportfwds
, &pf
, NULL
);
4113 sprintf(buf
, "Rejected remote port open request for %s:%d",
4116 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4117 PKT_INT
, remoteid
, PKT_END
);
4119 sprintf(buf
, "Received remote port open request for %s:%d",
4122 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
4123 c
, &ssh
->cfg
, pfp
->pfrec
->addressfamily
);
4126 sprintf(buf
, "Port open failed: %s", e
);
4129 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4130 PKT_INT
, remoteid
, PKT_END
);
4132 c
->remoteid
= remoteid
;
4133 c
->localid
= alloc_channel_id(ssh
);
4135 c
->v
.v1
.throttling
= 0;
4136 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
4137 add234(ssh
->channels
, c
);
4138 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4139 PKT_INT
, c
->remoteid
, PKT_INT
,
4140 c
->localid
, PKT_END
);
4141 logevent("Forwarded port opened successfully");
4146 static void ssh1_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
4148 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4149 unsigned int localid
= ssh_pkt_getuint32(pktin
);
4150 struct ssh_channel
*c
;
4152 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4153 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4154 c
->remoteid
= localid
;
4155 c
->type
= CHAN_SOCKDATA
;
4156 c
->v
.v1
.throttling
= 0;
4157 pfd_confirm(c
->u
.pfd
.s
);
4160 if (c
&& c
->closes
) {
4162 * We have a pending close on this channel,
4163 * which we decided on before the server acked
4164 * the channel open. So now we know the
4165 * remoteid, we can close it again.
4167 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
4168 PKT_INT
, c
->remoteid
, PKT_END
);
4172 static void ssh1_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
4174 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4175 struct ssh_channel
*c
;
4177 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4178 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4179 logevent("Forwarded connection refused by server");
4180 pfd_close(c
->u
.pfd
.s
);
4181 del234(ssh
->channels
, c
);
4186 static void ssh1_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
4188 /* Remote side closes a channel. */
4189 unsigned i
= ssh_pkt_getuint32(pktin
);
4190 struct ssh_channel
*c
;
4191 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4192 if (c
&& ((int)c
->remoteid
) != -1) {
4195 (pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
4197 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
4198 logevent("Forwarded X11 connection terminated");
4199 assert(c
->u
.x11
.s
!= NULL
);
4200 x11_close(c
->u
.x11
.s
);
4203 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
4204 logevent("Forwarded port closed");
4205 assert(c
->u
.pfd
.s
!= NULL
);
4206 pfd_close(c
->u
.pfd
.s
);
4210 c
->closes
|= (closetype
<< 2); /* seen this message */
4211 if (!(c
->closes
& closetype
)) {
4212 send_packet(ssh
, pktin
->type
, PKT_INT
, c
->remoteid
,
4214 c
->closes
|= closetype
; /* sent it too */
4217 if (c
->closes
== 15) {
4218 del234(ssh
->channels
, c
);
4222 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4223 pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
4224 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
4229 static void ssh1_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
4231 /* Data sent down one of our channels. */
4232 int i
= ssh_pkt_getuint32(pktin
);
4235 struct ssh_channel
*c
;
4237 ssh_pkt_getstring(pktin
, &p
, &len
);
4239 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4244 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
4247 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
4250 /* Data for an agent message. Buffer it. */
4252 if (c
->u
.a
.lensofar
< 4) {
4253 unsigned int l
= min(4 - c
->u
.a
.lensofar
, len
);
4254 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
4258 c
->u
.a
.lensofar
+= l
;
4260 if (c
->u
.a
.lensofar
== 4) {
4262 4 + GET_32BIT(c
->u
.a
.msglen
);
4263 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
4265 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
4267 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
4269 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
4271 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
4275 c
->u
.a
.lensofar
+= l
;
4277 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
4280 if (agent_query(c
->u
.a
.message
,
4283 ssh_agentf_callback
, c
))
4284 ssh_agentf_callback(c
, reply
, replylen
);
4285 sfree(c
->u
.a
.message
);
4286 c
->u
.a
.lensofar
= 0;
4289 bufsize
= 0; /* agent channels never back up */
4292 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4293 c
->v
.v1
.throttling
= 1;
4294 ssh1_throttle(ssh
, +1);
4299 static void ssh1_smsg_exit_status(Ssh ssh
, struct Packet
*pktin
)
4302 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
4303 sprintf(buf
, "Server sent command exit status %d",
4306 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
4308 * In case `helpful' firewalls or proxies tack
4309 * extra human-readable text on the end of the
4310 * session which we might mistake for another
4311 * encrypted packet, we close the session once
4312 * we've sent EXIT_CONFIRMATION.
4314 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4317 static void do_ssh1_connection(Ssh ssh
, unsigned char *in
, int inlen
,
4318 struct Packet
*pktin
)
4320 crBegin(ssh
->do_ssh1_connection_crstate
);
4322 ssh
->packet_dispatch
[SSH1_SMSG_STDOUT_DATA
] =
4323 ssh
->packet_dispatch
[SSH1_SMSG_STDERR_DATA
] =
4324 ssh1_smsg_stdout_stderr_data
;
4326 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
] =
4327 ssh1_msg_channel_open_confirmation
;
4328 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_FAILURE
] =
4329 ssh1_msg_channel_open_failure
;
4330 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE
] =
4331 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
] =
4332 ssh1_msg_channel_close
;
4333 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_DATA
] = ssh1_msg_channel_data
;
4334 ssh
->packet_dispatch
[SSH1_SMSG_EXIT_STATUS
] = ssh1_smsg_exit_status
;
4336 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
4337 logevent("Requesting agent forwarding");
4338 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
4342 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4343 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4344 bombout(("Protocol confusion"));
4346 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4347 logevent("Agent forwarding refused");
4349 logevent("Agent forwarding enabled");
4350 ssh
->agentfwd_enabled
= TRUE
;
4351 ssh
->packet_dispatch
[SSH1_SMSG_AGENT_OPEN
] = ssh1_smsg_agent_open
;
4355 if (ssh
->cfg
.x11_forward
) {
4356 char proto
[20], data
[64];
4357 logevent("Requesting X11 forwarding");
4358 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
4359 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
4360 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
4361 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
4362 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4363 PKT_STR
, proto
, PKT_STR
, data
,
4364 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
4367 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4368 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
4373 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4374 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4375 bombout(("Protocol confusion"));
4377 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4378 logevent("X11 forwarding refused");
4380 logevent("X11 forwarding enabled");
4381 ssh
->X11_fwd_enabled
= TRUE
;
4382 ssh
->packet_dispatch
[SSH1_SMSG_X11_OPEN
] = ssh1_smsg_x11_open
;
4386 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
4387 ssh
->packet_dispatch
[SSH1_MSG_PORT_OPEN
] = ssh1_msg_port_open
;
4389 if (!ssh
->cfg
.nopty
) {
4390 /* Unpick the terminal-speed string. */
4391 /* XXX perhaps we should allow no speeds to be sent. */
4392 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
4393 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
4394 /* Send the pty request. */
4395 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
4396 PKT_STR
, ssh
->cfg
.termtype
,
4397 PKT_INT
, ssh
->term_height
,
4398 PKT_INT
, ssh
->term_width
,
4399 PKT_INT
, 0, PKT_INT
, 0, /* width,height in pixels */
4400 PKT_CHAR
, 192, PKT_INT
, ssh
->ispeed
, /* TTY_OP_ISPEED */
4401 PKT_CHAR
, 193, PKT_INT
, ssh
->ospeed
, /* TTY_OP_OSPEED */
4402 PKT_CHAR
, 0, PKT_END
);
4403 ssh
->state
= SSH_STATE_INTERMED
;
4407 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4408 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4409 bombout(("Protocol confusion"));
4411 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4412 c_write_str(ssh
, "Server refused to allocate pty\r\n");
4413 ssh
->editing
= ssh
->echoing
= 1;
4415 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
4416 ssh
->ospeed
, ssh
->ispeed
);
4418 ssh
->editing
= ssh
->echoing
= 1;
4421 if (ssh
->cfg
.compression
) {
4422 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
4426 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4427 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4428 bombout(("Protocol confusion"));
4430 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4431 c_write_str(ssh
, "Server refused to compress\r\n");
4433 logevent("Started compression");
4434 ssh
->v1_compressing
= TRUE
;
4435 ssh
->cs_comp_ctx
= zlib_compress_init();
4436 logevent("Initialised zlib (RFC1950) compression");
4437 ssh
->sc_comp_ctx
= zlib_decompress_init();
4438 logevent("Initialised zlib (RFC1950) decompression");
4442 * Start the shell or command.
4444 * Special case: if the first-choice command is an SSH2
4445 * subsystem (hence not usable here) and the second choice
4446 * exists, we fall straight back to that.
4449 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
4451 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
4452 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
4453 ssh
->fallback_cmd
= TRUE
;
4456 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
4458 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
4459 logevent("Started session");
4462 ssh
->state
= SSH_STATE_SESSION
;
4463 if (ssh
->size_needed
)
4464 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
4465 if (ssh
->eof_needed
)
4466 ssh_special(ssh
, TS_EOF
);
4469 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
4471 ssh
->channels
= newtree234(ssh_channelcmp
);
4475 * By this point, most incoming packets are already being
4476 * handled by the dispatch table, and we need only pay
4477 * attention to the unusual ones.
4482 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
4483 /* may be from EXEC_SHELL on some servers */
4484 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4485 /* may be from EXEC_SHELL on some servers
4486 * if no pty is available or in other odd cases. Ignore */
4488 bombout(("Strange packet received: type %d", pktin
->type
));
4493 int len
= min(inlen
, 512);
4494 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4495 PKT_INT
, len
, PKT_DATA
, in
, len
,
4496 PKTT_OTHER
, PKT_END
);
4507 * Handle the top-level SSH2 protocol.
4509 static void ssh1_msg_debug(Ssh ssh
, struct Packet
*pktin
)
4514 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4515 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
4520 static void ssh1_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
4522 /* log reason code in disconnect message */
4526 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4527 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen
, msg
));
4530 void ssh_msg_ignore(Ssh ssh
, struct Packet
*pktin
)
4532 /* Do nothing, because we're ignoring it! Duhh. */
4535 static void ssh1_protocol_setup(Ssh ssh
)
4540 * Most messages are handled by the coroutines.
4542 for (i
= 0; i
< 256; i
++)
4543 ssh
->packet_dispatch
[i
] = NULL
;
4546 * These special message types we install handlers for.
4548 ssh
->packet_dispatch
[SSH1_MSG_DISCONNECT
] = ssh1_msg_disconnect
;
4549 ssh
->packet_dispatch
[SSH1_MSG_IGNORE
] = ssh_msg_ignore
;
4550 ssh
->packet_dispatch
[SSH1_MSG_DEBUG
] = ssh1_msg_debug
;
4553 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
4554 struct Packet
*pktin
)
4556 if (ssh
->state
== SSH_STATE_CLOSED
)
4559 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
4560 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
4564 if (!ssh
->protocol_initial_phase_done
) {
4565 if (do_ssh1_login(ssh
, in
, inlen
, pktin
))
4566 ssh
->protocol_initial_phase_done
= TRUE
;
4571 do_ssh1_connection(ssh
, in
, inlen
, pktin
);
4575 * Utility routine for decoding comma-separated strings in KEXINIT.
4577 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
4580 if (!needle
|| !haystack
) /* protect against null pointers */
4582 needlen
= strlen(needle
);
4585 * Is it at the start of the string?
4587 if (haylen
>= needlen
&& /* haystack is long enough */
4588 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4589 (haylen
== needlen
|| haystack
[needlen
] == ',')
4590 /* either , or EOS follows */
4594 * If not, search for the next comma and resume after that.
4595 * If no comma found, terminate.
4597 while (haylen
> 0 && *haystack
!= ',')
4598 haylen
--, haystack
++;
4601 haylen
--, haystack
++; /* skip over comma itself */
4606 * SSH2 key creation method.
4608 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
4609 unsigned char *sessid
, char chr
,
4610 unsigned char *keyspace
)
4613 /* First 20 bytes. */
4615 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4617 SHA_Bytes(&s
, H
, 20);
4618 SHA_Bytes(&s
, &chr
, 1);
4619 SHA_Bytes(&s
, sessid
, 20);
4620 SHA_Final(&s
, keyspace
);
4621 /* Next 20 bytes. */
4623 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4625 SHA_Bytes(&s
, H
, 20);
4626 SHA_Bytes(&s
, keyspace
, 20);
4627 SHA_Final(&s
, keyspace
+ 20);
4631 * Handle the SSH2 transport layer.
4633 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
,
4634 struct Packet
*pktin
)
4636 struct do_ssh2_transport_state
{
4637 int nbits
, pbits
, warn
;
4638 Bignum p
, g
, e
, f
, K
;
4639 int kex_init_value
, kex_reply_value
;
4640 const struct ssh_mac
**maclist
;
4642 const struct ssh2_cipher
*cscipher_tobe
;
4643 const struct ssh2_cipher
*sccipher_tobe
;
4644 const struct ssh_mac
*csmac_tobe
;
4645 const struct ssh_mac
*scmac_tobe
;
4646 const struct ssh_compress
*cscomp_tobe
;
4647 const struct ssh_compress
*sccomp_tobe
;
4648 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4649 int hostkeylen
, siglen
;
4650 void *hkey
; /* actual host key */
4651 unsigned char exchange_hash
[20];
4652 int n_preferred_kex
;
4653 const struct ssh_kex
*preferred_kex
[KEX_MAX
];
4654 int n_preferred_ciphers
;
4655 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
4656 const struct ssh_compress
*preferred_comp
;
4657 int got_session_id
, activated_authconn
;
4658 struct Packet
*pktout
;
4660 crState(do_ssh2_transport_state
);
4662 crBegin(ssh
->do_ssh2_transport_crstate
);
4664 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
4665 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
4666 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
4668 s
->got_session_id
= s
->activated_authconn
= FALSE
;
4671 * Be prepared to work around the buggy MAC problem.
4673 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
4674 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
4676 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
4679 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_KEX_MASK
;
4681 int i
, j
, commalist_started
;
4684 * Set up the preferred key exchange. (NULL => warn below here)
4686 s
->n_preferred_kex
= 0;
4687 for (i
= 0; i
< KEX_MAX
; i
++) {
4688 switch (ssh
->cfg
.ssh_kexlist
[i
]) {
4690 s
->preferred_kex
[s
->n_preferred_kex
++] =
4691 &ssh_diffiehellman_gex
;
4694 s
->preferred_kex
[s
->n_preferred_kex
++] =
4695 &ssh_diffiehellman_group14
;
4698 s
->preferred_kex
[s
->n_preferred_kex
++] =
4699 &ssh_diffiehellman_group1
;
4702 /* Flag for later. Don't bother if it's the last in
4704 if (i
< KEX_MAX
- 1) {
4705 s
->preferred_kex
[s
->n_preferred_kex
++] = NULL
;
4712 * Set up the preferred ciphers. (NULL => warn below here)
4714 s
->n_preferred_ciphers
= 0;
4715 for (i
= 0; i
< CIPHER_MAX
; i
++) {
4716 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
4717 case CIPHER_BLOWFISH
:
4718 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
4721 if (ssh
->cfg
.ssh2_des_cbc
) {
4722 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
4726 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
4729 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
4732 /* Flag for later. Don't bother if it's the last in
4734 if (i
< CIPHER_MAX
- 1) {
4735 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
4742 * Set up preferred compression.
4744 if (ssh
->cfg
.compression
)
4745 s
->preferred_comp
= &ssh_zlib
;
4747 s
->preferred_comp
= &ssh_comp_none
;
4750 * Enable queueing of outgoing auth- or connection-layer
4751 * packets while we are in the middle of a key exchange.
4753 ssh
->queueing
= TRUE
;
4756 * Flag that KEX is in progress.
4758 ssh
->kex_in_progress
= TRUE
;
4761 * Construct and send our key exchange packet.
4763 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEXINIT
);
4764 for (i
= 0; i
< 16; i
++)
4765 ssh2_pkt_addbyte(s
->pktout
, (unsigned char) random_byte());
4766 /* List key exchange algorithms. */
4767 ssh2_pkt_addstring_start(s
->pktout
);
4768 commalist_started
= 0;
4769 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4770 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4771 if (!k
) continue; /* warning flag */
4772 if (commalist_started
)
4773 ssh2_pkt_addstring_str(s
->pktout
, ",");
4774 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_kex
[i
]->name
);
4775 commalist_started
= 1;
4777 /* List server host key algorithms. */
4778 ssh2_pkt_addstring_start(s
->pktout
);
4779 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4780 ssh2_pkt_addstring_str(s
->pktout
, hostkey_algs
[i
]->name
);
4781 if (i
< lenof(hostkey_algs
) - 1)
4782 ssh2_pkt_addstring_str(s
->pktout
, ",");
4784 /* List client->server encryption algorithms. */
4785 ssh2_pkt_addstring_start(s
->pktout
);
4786 commalist_started
= 0;
4787 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4788 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4789 if (!c
) continue; /* warning flag */
4790 for (j
= 0; j
< c
->nciphers
; j
++) {
4791 if (commalist_started
)
4792 ssh2_pkt_addstring_str(s
->pktout
, ",");
4793 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4794 commalist_started
= 1;
4797 /* List server->client encryption algorithms. */
4798 ssh2_pkt_addstring_start(s
->pktout
);
4799 commalist_started
= 0;
4800 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4801 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4802 if (!c
) continue; /* warning flag */
4803 for (j
= 0; j
< c
->nciphers
; j
++) {
4804 if (commalist_started
)
4805 ssh2_pkt_addstring_str(s
->pktout
, ",");
4806 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4807 commalist_started
= 1;
4810 /* List client->server MAC algorithms. */
4811 ssh2_pkt_addstring_start(s
->pktout
);
4812 for (i
= 0; i
< s
->nmacs
; i
++) {
4813 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4814 if (i
< s
->nmacs
- 1)
4815 ssh2_pkt_addstring_str(s
->pktout
, ",");
4817 /* List server->client MAC algorithms. */
4818 ssh2_pkt_addstring_start(s
->pktout
);
4819 for (i
= 0; i
< s
->nmacs
; i
++) {
4820 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4821 if (i
< s
->nmacs
- 1)
4822 ssh2_pkt_addstring_str(s
->pktout
, ",");
4824 /* List client->server compression algorithms. */
4825 ssh2_pkt_addstring_start(s
->pktout
);
4826 assert(lenof(compressions
) > 1);
4827 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4828 for (i
= 0; i
< lenof(compressions
); i
++) {
4829 const struct ssh_compress
*c
= compressions
[i
];
4830 if (c
!= s
->preferred_comp
) {
4831 ssh2_pkt_addstring_str(s
->pktout
, ",");
4832 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4835 /* List server->client compression algorithms. */
4836 ssh2_pkt_addstring_start(s
->pktout
);
4837 assert(lenof(compressions
) > 1);
4838 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4839 for (i
= 0; i
< lenof(compressions
); i
++) {
4840 const struct ssh_compress
*c
= compressions
[i
];
4841 if (c
!= s
->preferred_comp
) {
4842 ssh2_pkt_addstring_str(s
->pktout
, ",");
4843 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4846 /* List client->server languages. Empty list. */
4847 ssh2_pkt_addstring_start(s
->pktout
);
4848 /* List server->client languages. Empty list. */
4849 ssh2_pkt_addstring_start(s
->pktout
);
4850 /* First KEX packet does _not_ follow, because we're not that brave. */
4851 ssh2_pkt_addbool(s
->pktout
, FALSE
);
4853 ssh2_pkt_adduint32(s
->pktout
, 0);
4856 ssh
->exhash
= ssh
->exhashbase
;
4857 sha_string(&ssh
->exhash
, s
->pktout
->data
+ 5, s
->pktout
->length
- 5);
4859 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
4863 if (pktin
->length
> 5)
4864 sha_string(&ssh
->exhash
, pktin
->data
+ 5, pktin
->length
- 5);
4867 * Now examine the other side's KEXINIT to see what we're up
4874 if (pktin
->type
!= SSH2_MSG_KEXINIT
) {
4875 bombout(("expected key exchange packet from server"));
4879 ssh
->hostkey
= NULL
;
4880 s
->cscipher_tobe
= NULL
;
4881 s
->sccipher_tobe
= NULL
;
4882 s
->csmac_tobe
= NULL
;
4883 s
->scmac_tobe
= NULL
;
4884 s
->cscomp_tobe
= NULL
;
4885 s
->sccomp_tobe
= NULL
;
4886 pktin
->savedpos
+= 16; /* skip garbage cookie */
4887 ssh_pkt_getstring(pktin
, &str
, &len
); /* key exchange algorithms */
4889 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4890 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4893 } else if (in_commasep_string(k
->name
, str
, len
)) {
4898 sk_set_frozen(ssh
->s
, 1);
4899 askalg(ssh
->frontend
, "key-exchange algorithm",
4901 sk_set_frozen(ssh
->s
, 0);
4907 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
4908 str ? str
: "(null)"));
4911 ssh_pkt_getstring(pktin
, &str
, &len
); /* host key algorithms */
4912 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4913 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
4914 ssh
->hostkey
= hostkey_algs
[i
];
4918 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server cipher */
4920 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4921 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4925 for (j
= 0; j
< c
->nciphers
; j
++) {
4926 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4927 s
->cscipher_tobe
= c
->list
[j
];
4932 if (s
->cscipher_tobe
) {
4934 sk_set_frozen(ssh
->s
, 1);
4935 askalg(ssh
->frontend
, "client-to-server cipher",
4936 s
->cscipher_tobe
->name
);
4937 sk_set_frozen(ssh
->s
, 0);
4942 if (!s
->cscipher_tobe
) {
4943 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
4944 str ? str
: "(null)"));
4948 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client cipher */
4950 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4951 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4955 for (j
= 0; j
< c
->nciphers
; j
++) {
4956 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4957 s
->sccipher_tobe
= c
->list
[j
];
4962 if (s
->sccipher_tobe
) {
4964 sk_set_frozen(ssh
->s
, 1);
4965 askalg(ssh
->frontend
, "server-to-client cipher",
4966 s
->sccipher_tobe
->name
);
4967 sk_set_frozen(ssh
->s
, 0);
4972 if (!s
->sccipher_tobe
) {
4973 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
4974 str ? str
: "(null)"));
4978 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server mac */
4979 for (i
= 0; i
< s
->nmacs
; i
++) {
4980 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4981 s
->csmac_tobe
= s
->maclist
[i
];
4985 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client mac */
4986 for (i
= 0; i
< s
->nmacs
; i
++) {
4987 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4988 s
->scmac_tobe
= s
->maclist
[i
];
4992 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server compression */
4993 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
4994 const struct ssh_compress
*c
=
4995 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
4996 if (in_commasep_string(c
->name
, str
, len
)) {
5001 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client compression */
5002 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5003 const struct ssh_compress
*c
=
5004 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5005 if (in_commasep_string(c
->name
, str
, len
)) {
5013 * Work out the number of bits of key we will need from the key
5014 * exchange. We start with the maximum key length of either
5020 csbits
= s
->cscipher_tobe
->keylen
;
5021 scbits
= s
->sccipher_tobe
->keylen
;
5022 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
5024 /* The keys only have 160-bit entropy, since they're based on
5025 * a SHA-1 hash. So cap the key size at 160 bits. */
5030 * If we're doing Diffie-Hellman group exchange, start by
5031 * requesting a group.
5033 if (!ssh
->kex
->pdata
) {
5034 logevent("Doing Diffie-Hellman group exchange");
5035 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
5037 * Work out how big a DH group we will need to allow that
5040 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
5041 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
5042 ssh2_pkt_adduint32(s
->pktout
, s
->pbits
);
5043 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5046 if (pktin
->type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
5047 bombout(("expected key exchange group packet from server"));
5050 s
->p
= ssh2_pkt_getmp(pktin
);
5051 s
->g
= ssh2_pkt_getmp(pktin
);
5052 if (!s
->p
|| !s
->g
) {
5053 bombout(("unable to read mp-ints from incoming group packet"));
5056 ssh
->kex_ctx
= dh_setup_gex(s
->p
, s
->g
);
5057 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
5058 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
5060 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP
;
5061 ssh
->kex_ctx
= dh_setup_group(ssh
->kex
);
5062 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
5063 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
5064 logeventf(ssh
, "Using Diffie-Hellman with standard group \"%s\"",
5065 ssh
->kex
->groupname
);
5068 logevent("Doing Diffie-Hellman key exchange");
5070 * Now generate and send e for Diffie-Hellman.
5072 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
5073 s
->pktout
= ssh2_pkt_init(s
->kex_init_value
);
5074 ssh2_pkt_addmp(s
->pktout
, s
->e
);
5075 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5078 if (pktin
->type
!= s
->kex_reply_value
) {
5079 bombout(("expected key exchange reply packet from server"));
5082 ssh_pkt_getstring(pktin
, &s
->hostkeydata
, &s
->hostkeylen
);
5083 s
->f
= ssh2_pkt_getmp(pktin
);
5085 bombout(("unable to parse key exchange reply packet"));
5088 ssh_pkt_getstring(pktin
, &s
->sigdata
, &s
->siglen
);
5090 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
5092 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
5093 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5094 sha_uint32(&ssh
->exhash
, s
->pbits
);
5095 sha_mpint(&ssh
->exhash
, s
->p
);
5096 sha_mpint(&ssh
->exhash
, s
->g
);
5098 sha_mpint(&ssh
->exhash
, s
->e
);
5099 sha_mpint(&ssh
->exhash
, s
->f
);
5100 sha_mpint(&ssh
->exhash
, s
->K
);
5101 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
5103 dh_cleanup(ssh
->kex_ctx
);
5104 ssh
->kex_ctx
= NULL
;
5107 debug(("Exchange hash is:\n"));
5108 dmemdump(s
->exchange_hash
, 20);
5111 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
5113 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
5114 (char *)s
->exchange_hash
, 20)) {
5115 bombout(("Server's host key did not match the signature supplied"));
5120 * Authenticate remote host: verify host key. (We've already
5121 * checked the signature of the exchange hash.)
5123 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
5124 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
5125 sk_set_frozen(ssh
->s
, 1);
5126 verify_ssh_host_key(ssh
->frontend
,
5127 ssh
->savedhost
, ssh
->savedport
, ssh
->hostkey
->keytype
,
5128 s
->keystr
, s
->fingerprint
);
5129 sk_set_frozen(ssh
->s
, 0);
5130 if (!s
->got_session_id
) { /* don't bother logging this in rekeys */
5131 logevent("Host key fingerprint is:");
5132 logevent(s
->fingerprint
);
5134 sfree(s
->fingerprint
);
5136 ssh
->hostkey
->freekey(s
->hkey
);
5139 * The exchange hash from the very first key exchange is also
5140 * the session id, used in session key construction and
5143 if (!s
->got_session_id
) {
5144 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
5145 sizeof(s
->exchange_hash
));
5146 s
->got_session_id
= TRUE
;
5150 * Send SSH2_MSG_NEWKEYS.
5152 s
->pktout
= ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
5153 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5154 ssh
->outgoing_data_size
= 0; /* start counting from here */
5157 * We've sent client NEWKEYS, so create and initialise
5158 * client-to-server session keys.
5160 if (ssh
->cs_cipher_ctx
)
5161 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
5162 ssh
->cscipher
= s
->cscipher_tobe
;
5163 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
5165 if (ssh
->cs_mac_ctx
)
5166 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
5167 ssh
->csmac
= s
->csmac_tobe
;
5168 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
5170 if (ssh
->cs_comp_ctx
)
5171 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
5172 ssh
->cscomp
= s
->cscomp_tobe
;
5173 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
5176 * Set IVs on client-to-server keys. Here we use the exchange
5177 * hash from the _first_ key exchange.
5180 unsigned char keyspace
[40];
5181 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
5182 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
5183 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
5184 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
5185 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
5186 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
5189 logeventf(ssh
, "Initialised %.200s client->server encryption",
5190 ssh
->cscipher
->text_name
);
5191 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
5192 ssh
->csmac
->text_name
);
5193 if (ssh
->cscomp
->text_name
)
5194 logeventf(ssh
, "Initialised %s compression",
5195 ssh
->cscomp
->text_name
);
5198 * Now our end of the key exchange is complete, we can send all
5199 * our queued higher-layer packets.
5201 ssh
->queueing
= FALSE
;
5202 ssh2_pkt_queuesend(ssh
);
5205 * Expect SSH2_MSG_NEWKEYS from server.
5208 if (pktin
->type
!= SSH2_MSG_NEWKEYS
) {
5209 bombout(("expected new-keys packet from server"));
5212 ssh
->incoming_data_size
= 0; /* start counting from here */
5215 * We've seen server NEWKEYS, so create and initialise
5216 * server-to-client session keys.
5218 if (ssh
->sc_cipher_ctx
)
5219 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
5220 ssh
->sccipher
= s
->sccipher_tobe
;
5221 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
5223 if (ssh
->sc_mac_ctx
)
5224 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
5225 ssh
->scmac
= s
->scmac_tobe
;
5226 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
5228 if (ssh
->sc_comp_ctx
)
5229 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
5230 ssh
->sccomp
= s
->sccomp_tobe
;
5231 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
5234 * Set IVs on server-to-client keys. Here we use the exchange
5235 * hash from the _first_ key exchange.
5238 unsigned char keyspace
[40];
5239 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
5240 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
5241 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
5242 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
5243 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
5244 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
5246 logeventf(ssh
, "Initialised %.200s server->client encryption",
5247 ssh
->sccipher
->text_name
);
5248 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
5249 ssh
->scmac
->text_name
);
5250 if (ssh
->sccomp
->text_name
)
5251 logeventf(ssh
, "Initialised %s decompression",
5252 ssh
->sccomp
->text_name
);
5255 * Free key exchange data.
5259 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5265 * Key exchange is over. Loop straight back round if we have a
5266 * deferred rekey reason.
5268 if (ssh
->deferred_rekey_reason
) {
5269 logevent(ssh
->deferred_rekey_reason
);
5271 ssh
->deferred_rekey_reason
= NULL
;
5272 goto begin_key_exchange
;
5276 * Otherwise, schedule a timer for our next rekey.
5278 ssh
->kex_in_progress
= FALSE
;
5279 ssh
->last_rekey
= GETTICKCOUNT();
5280 if (ssh
->cfg
.ssh_rekey_time
!= 0)
5281 ssh
->next_rekey
= schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5285 * If this is the first key exchange phase, we must pass the
5286 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5287 * wants to see it but because it will need time to initialise
5288 * itself before it sees an actual packet. In subsequent key
5289 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5290 * it would only confuse the layer above.
5292 if (s
->activated_authconn
) {
5295 s
->activated_authconn
= TRUE
;
5298 * Now we're encrypting. Begin returning 1 to the protocol main
5299 * function so that other things can run on top of the
5300 * transport. If we ever see a KEXINIT, we must go back to the
5303 * We _also_ go back to the start if we see pktin==NULL and
5304 * inlen==-1, because this is a special signal meaning
5305 * `initiate client-driven rekey', and `in' contains a message
5306 * giving the reason for the rekey.
5308 while (!((pktin
&& pktin
->type
== SSH2_MSG_KEXINIT
) ||
5309 (!pktin
&& inlen
== -1))) {
5313 logevent("Server initiated key re-exchange");
5315 logevent((char *)in
);
5317 goto begin_key_exchange
;
5323 * Add data to an SSH2 channel output buffer.
5325 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
5328 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
5332 * Attempt to send data on an SSH2 channel.
5334 static int ssh2_try_send(struct ssh_channel
*c
)
5337 struct Packet
*pktout
;
5339 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
5342 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
5343 if ((unsigned)len
> c
->v
.v2
.remwindow
)
5344 len
= c
->v
.v2
.remwindow
;
5345 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
5346 len
= c
->v
.v2
.remmaxpkt
;
5347 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
5348 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5349 dont_log_data(ssh
, pktout
, PKTLOG_OMIT
);
5350 ssh2_pkt_addstring_start(pktout
);
5351 ssh2_pkt_addstring_data(pktout
, data
, len
);
5352 end_log_omission(ssh
, pktout
);
5353 ssh2_pkt_send(ssh
, pktout
);
5354 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
5355 c
->v
.v2
.remwindow
-= len
;
5359 * After having sent as much data as we can, return the amount
5362 return bufchain_size(&c
->v
.v2
.outbuffer
);
5366 * Potentially enlarge the window on an SSH2 channel.
5368 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
5373 * Never send WINDOW_ADJUST for a channel that the remote side
5374 * already thinks it's closed; there's no point, since it won't
5375 * be sending any more data anyway.
5380 if (newwin
> c
->v
.v2
.locwindow
) {
5381 struct Packet
*pktout
;
5383 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5384 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5385 ssh2_pkt_adduint32(pktout
, newwin
- c
->v
.v2
.locwindow
);
5386 ssh2_pkt_send(ssh
, pktout
);
5387 c
->v
.v2
.locwindow
= newwin
;
5391 static void ssh2_msg_channel_window_adjust(Ssh ssh
, struct Packet
*pktin
)
5393 unsigned i
= ssh_pkt_getuint32(pktin
);
5394 struct ssh_channel
*c
;
5395 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5396 if (c
&& !c
->closes
)
5397 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
5400 static void ssh2_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
5403 unsigned int length
;
5404 unsigned i
= ssh_pkt_getuint32(pktin
);
5405 struct ssh_channel
*c
;
5406 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5408 return; /* nonexistent channel */
5409 if (pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5410 ssh_pkt_getuint32(pktin
) != SSH2_EXTENDED_DATA_STDERR
)
5411 return; /* extended but not stderr */
5412 ssh_pkt_getstring(pktin
, &data
, &length
);
5415 c
->v
.v2
.locwindow
-= length
;
5417 case CHAN_MAINSESSION
:
5419 from_backend(ssh
->frontend
, pktin
->type
==
5420 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5424 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5427 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5430 while (length
> 0) {
5431 if (c
->u
.a
.lensofar
< 4) {
5432 unsigned int l
= min(4 - c
->u
.a
.lensofar
, length
);
5433 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5437 c
->u
.a
.lensofar
+= l
;
5439 if (c
->u
.a
.lensofar
== 4) {
5441 4 + GET_32BIT(c
->u
.a
.msglen
);
5442 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
5444 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5446 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5448 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5450 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5454 c
->u
.a
.lensofar
+= l
;
5456 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5459 if (agent_query(c
->u
.a
.message
,
5462 ssh_agentf_callback
, c
))
5463 ssh_agentf_callback(c
, reply
, replylen
);
5464 sfree(c
->u
.a
.message
);
5465 c
->u
.a
.lensofar
= 0;
5472 * If we are not buffering too much data,
5473 * enlarge the window again at the remote side.
5475 if (bufsize
< OUR_V2_WINSIZE
)
5476 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5480 static void ssh2_msg_channel_eof(Ssh ssh
, struct Packet
*pktin
)
5482 unsigned i
= ssh_pkt_getuint32(pktin
);
5483 struct ssh_channel
*c
;
5485 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5487 return; /* nonexistent channel */
5489 if (c
->type
== CHAN_X11
) {
5491 * Remote EOF on an X11 channel means we should
5492 * wrap up and close the channel ourselves.
5494 x11_close(c
->u
.x11
.s
);
5496 } else if (c
->type
== CHAN_AGENT
) {
5498 } else if (c
->type
== CHAN_SOCKDATA
) {
5499 pfd_close(c
->u
.pfd
.s
);
5504 static void ssh2_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
5506 unsigned i
= ssh_pkt_getuint32(pktin
);
5507 struct ssh_channel
*c
;
5508 struct Packet
*pktout
;
5510 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5511 if (!c
|| ((int)c
->remoteid
) == -1) {
5512 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5513 c ?
"half-open" : "nonexistent", i
));
5516 /* Do pre-close processing on the channel. */
5518 case CHAN_MAINSESSION
:
5519 ssh
->mainchan
= NULL
;
5520 update_specials_menu(ssh
->frontend
);
5523 if (c
->u
.x11
.s
!= NULL
)
5524 x11_close(c
->u
.x11
.s
);
5531 if (c
->u
.pfd
.s
!= NULL
)
5532 pfd_close(c
->u
.pfd
.s
);
5536 if (c
->closes
== 0) {
5537 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5538 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5539 ssh2_pkt_send(ssh
, pktout
);
5541 del234(ssh
->channels
, c
);
5542 bufchain_clear(&c
->v
.v2
.outbuffer
);
5546 * See if that was the last channel left open.
5547 * (This is only our termination condition if we're
5548 * not running in -N mode.)
5550 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
5551 logevent("All channels closed. Disconnecting");
5554 * We used to send SSH_MSG_DISCONNECT here,
5555 * because I'd believed that _every_ conforming
5556 * SSH2 connection had to end with a disconnect
5557 * being sent by at least one side; apparently
5558 * I was wrong and it's perfectly OK to
5559 * unceremoniously slam the connection shut
5560 * when you're done, and indeed OpenSSH feels
5561 * this is more polite than sending a
5562 * DISCONNECT. So now we don't.
5564 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5565 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5566 ssh2_pkt_addstring(s
->pktout
, "All open channels closed");
5567 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
5568 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5570 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5574 static void ssh2_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
5576 unsigned i
= ssh_pkt_getuint32(pktin
);
5577 struct ssh_channel
*c
;
5578 struct Packet
*pktout
;
5580 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5582 return; /* nonexistent channel */
5583 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5584 return; /* dunno why they're confirming this */
5585 c
->remoteid
= ssh_pkt_getuint32(pktin
);
5586 c
->type
= CHAN_SOCKDATA
;
5587 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
5588 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
5590 pfd_confirm(c
->u
.pfd
.s
);
5593 * We have a pending close on this channel,
5594 * which we decided on before the server acked
5595 * the channel open. So now we know the
5596 * remoteid, we can close it again.
5598 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5599 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5600 ssh2_pkt_send(ssh
, pktout
);
5604 static void ssh2_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
5606 static const char *const reasons
[] = {
5607 "<unknown reason code>",
5608 "Administratively prohibited",
5610 "Unknown channel type",
5611 "Resource shortage",
5613 unsigned i
= ssh_pkt_getuint32(pktin
);
5614 unsigned reason_code
;
5615 char *reason_string
;
5618 struct ssh_channel
*c
;
5619 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5621 return; /* nonexistent channel */
5622 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5623 return; /* dunno why they're failing this */
5625 reason_code
= ssh_pkt_getuint32(pktin
);
5626 if (reason_code
>= lenof(reasons
))
5627 reason_code
= 0; /* ensure reasons[reason_code] in range */
5628 ssh_pkt_getstring(pktin
, &reason_string
, &reason_length
);
5629 message
= dupprintf("Forwarded connection refused by"
5630 " server: %s [%.*s]", reasons
[reason_code
],
5631 reason_length
, reason_string
);
5635 pfd_close(c
->u
.pfd
.s
);
5637 del234(ssh
->channels
, c
);
5641 static void ssh2_msg_channel_request(Ssh ssh
, struct Packet
*pktin
)
5645 int typelen
, want_reply
;
5646 int reply
= SSH2_MSG_CHANNEL_FAILURE
; /* default */
5647 struct ssh_channel
*c
;
5648 struct Packet
*pktout
;
5650 localid
= ssh_pkt_getuint32(pktin
);
5651 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5652 want_reply
= ssh2_pkt_getbool(pktin
);
5655 * First, check that the channel exists. Otherwise,
5656 * we can instantly disconnect with a rude message.
5658 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
5661 sprintf(buf
, "Received channel request for nonexistent"
5662 " channel %d", localid
);
5664 pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5665 ssh2_pkt_adduint32(pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5666 ssh2_pkt_addstring(pktout
, buf
);
5667 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5668 ssh2_pkt_send_noqueue(ssh
, pktout
);
5669 connection_fatal(ssh
->frontend
, "%s", buf
);
5670 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5675 * Having got the channel number, we now look at
5676 * the request type string to see if it's something
5679 if (c
== ssh
->mainchan
) {
5681 * We recognise "exit-status" and "exit-signal" on
5682 * the primary channel.
5684 if (typelen
== 11 &&
5685 !memcmp(type
, "exit-status", 11)) {
5687 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
5688 logeventf(ssh
, "Server sent command exit status %d",
5690 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5692 } else if (typelen
== 11 &&
5693 !memcmp(type
, "exit-signal", 11)) {
5695 int is_plausible
= TRUE
, is_int
= FALSE
;
5696 char *fmt_sig
= "", *fmt_msg
= "";
5698 int msglen
= 0, core
= FALSE
;
5699 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
5700 * provide an `int' for the signal, despite its
5701 * having been a `string' in the drafts since at
5702 * least 2001. (Fixed in session.c 1.147.) Try to
5703 * infer which we can safely parse it as. */
5705 unsigned char *p
= pktin
->body
+
5707 long len
= pktin
->length
- pktin
->savedpos
;
5708 unsigned long num
= GET_32BIT(p
); /* what is it? */
5709 /* If it's 0, it hardly matters; assume string */
5713 int maybe_int
= FALSE
, maybe_str
= FALSE
;
5714 #define CHECK_HYPOTHESIS(offset, result) \
5717 if (q >= 0 && q+4 <= len) { \
5718 q = q + 4 + GET_32BIT(p+q); \
5719 if (q >= 0 && q+4 <= len && \
5720 (q = q + 4 + GET_32BIT(p+q)) && q == len) \
5724 CHECK_HYPOTHESIS(4+1, maybe_int
);
5725 CHECK_HYPOTHESIS(4+num
+1, maybe_str
);
5726 #undef CHECK_HYPOTHESIS
5727 if (maybe_int
&& !maybe_str
)
5729 else if (!maybe_int
&& maybe_str
)
5732 /* Crikey. Either or neither. Panic. */
5733 is_plausible
= FALSE
;
5738 /* Old non-standard OpenSSH. */
5739 int signum
= ssh_pkt_getuint32(pktin
);
5740 fmt_sig
= dupprintf(" %d", signum
);
5742 /* As per the drafts. */
5745 ssh_pkt_getstring(pktin
, &sig
, &siglen
);
5746 /* Signal name isn't supposed to be blank, but
5747 * let's cope gracefully if it is. */
5749 fmt_sig
= dupprintf(" \"%.*s\"",
5753 core
= ssh2_pkt_getbool(pktin
);
5754 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
5756 fmt_msg
= dupprintf(" (\"%.*s\")", msglen
, msg
);
5758 /* ignore lang tag */
5759 } /* else don't attempt to parse */
5760 logeventf(ssh
, "Server exited on signal%s%s%s",
5761 fmt_sig
, core ?
" (core dumped)" : "",
5763 if (*fmt_sig
) sfree(fmt_sig
);
5764 if (*fmt_msg
) sfree(fmt_msg
);
5765 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5770 * This is a channel request we don't know
5771 * about, so we now either ignore the request
5772 * or respond with CHANNEL_FAILURE, depending
5775 reply
= SSH2_MSG_CHANNEL_FAILURE
;
5778 pktout
= ssh2_pkt_init(reply
);
5779 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5780 ssh2_pkt_send(ssh
, pktout
);
5784 static void ssh2_msg_global_request(Ssh ssh
, struct Packet
*pktin
)
5787 int typelen
, want_reply
;
5788 struct Packet
*pktout
;
5790 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5791 want_reply
= ssh2_pkt_getbool(pktin
);
5794 * We currently don't support any global requests
5795 * at all, so we either ignore the request or
5796 * respond with REQUEST_FAILURE, depending on
5800 pktout
= ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
5801 ssh2_pkt_send(ssh
, pktout
);
5805 static void ssh2_msg_channel_open(Ssh ssh
, struct Packet
*pktin
)
5813 struct ssh_channel
*c
;
5814 unsigned remid
, winsize
, pktsize
;
5815 struct Packet
*pktout
;
5817 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5818 c
= snew(struct ssh_channel
);
5821 remid
= ssh_pkt_getuint32(pktin
);
5822 winsize
= ssh_pkt_getuint32(pktin
);
5823 pktsize
= ssh_pkt_getuint32(pktin
);
5825 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5828 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5829 addrstr
= snewn(peeraddrlen
+1, char);
5830 memcpy(addrstr
, peeraddr
, peeraddrlen
);
5831 addrstr
[peeraddrlen
] = '\0';
5832 peerport
= ssh_pkt_getuint32(pktin
);
5834 logeventf(ssh
, "Received X11 connect request from %s:%d",
5837 if (!ssh
->X11_fwd_enabled
)
5838 error
= "X11 forwarding is not enabled";
5839 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
5840 ssh
->x11auth
, addrstr
, peerport
,
5841 &ssh
->cfg
) != NULL
) {
5842 error
= "Unable to open an X11 connection";
5844 logevent("Opening X11 forward connection succeeded");
5849 } else if (typelen
== 15 &&
5850 !memcmp(type
, "forwarded-tcpip", 15)) {
5851 struct ssh_rportfwd pf
, *realpf
;
5854 ssh_pkt_getstring(pktin
, &dummy
, &dummylen
);/* skip address */
5855 pf
.sport
= ssh_pkt_getuint32(pktin
);
5856 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5857 peerport
= ssh_pkt_getuint32(pktin
);
5858 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
5859 logeventf(ssh
, "Received remote port %d open request "
5860 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
5861 if (realpf
== NULL
) {
5862 error
= "Remote port is not recognised";
5864 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
5868 realpf
->pfrec
->addressfamily
);
5869 logeventf(ssh
, "Attempting to forward remote port to "
5870 "%s:%d", realpf
->dhost
, realpf
->dport
);
5872 logeventf(ssh
, "Port open failed: %s", e
);
5873 error
= "Port open failed";
5875 logevent("Forwarded port opened successfully");
5876 c
->type
= CHAN_SOCKDATA
;
5879 } else if (typelen
== 22 &&
5880 !memcmp(type
, "auth-agent@openssh.com", 3)) {
5881 if (!ssh
->agentfwd_enabled
)
5882 error
= "Agent forwarding is not enabled";
5884 c
->type
= CHAN_AGENT
; /* identify channel type */
5885 c
->u
.a
.lensofar
= 0;
5888 error
= "Unsupported channel type requested";
5891 c
->remoteid
= remid
;
5893 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
5894 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5895 ssh2_pkt_adduint32(pktout
, SSH2_OPEN_CONNECT_FAILED
);
5896 ssh2_pkt_addstring(pktout
, error
);
5897 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5898 ssh2_pkt_send(ssh
, pktout
);
5899 logeventf(ssh
, "Rejected channel open: %s", error
);
5902 c
->localid
= alloc_channel_id(ssh
);
5904 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5905 c
->v
.v2
.remwindow
= winsize
;
5906 c
->v
.v2
.remmaxpkt
= pktsize
;
5907 bufchain_init(&c
->v
.v2
.outbuffer
);
5908 add234(ssh
->channels
, c
);
5909 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
5910 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5911 ssh2_pkt_adduint32(pktout
, c
->localid
);
5912 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);
5913 ssh2_pkt_adduint32(pktout
, 0x4000UL
); /* our max pkt size */
5914 ssh2_pkt_send(ssh
, pktout
);
5919 * Handle the SSH2 userauth and connection layers.
5921 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
5922 struct Packet
*pktin
)
5924 struct do_ssh2_authconn_state
{
5926 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
5928 AUTH_KEYBOARD_INTERACTIVE
5932 AUTH_TYPE_PUBLICKEY
,
5933 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
5934 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
5936 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
5937 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
5939 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
5940 int tried_pubkey_config
, tried_agent
;
5941 int kbd_inter_running
, kbd_inter_refused
;
5943 int num_prompts
, curr_prompt
, echo
;
5948 void *publickey_blob
;
5949 int publickey_bloblen
;
5950 unsigned char request
[5], *response
, *p
;
5954 char *pkblob
, *alg
, *commentp
;
5955 int pklen
, alglen
, commentlen
;
5956 int siglen
, retlen
, len
;
5957 char *q
, *agentreq
, *ret
;
5959 int num_env
, env_left
, env_ok
;
5960 struct Packet
*pktout
;
5962 crState(do_ssh2_authconn_state
);
5964 crBegin(ssh
->do_ssh2_authconn_crstate
);
5967 * Request userauth protocol, and await a response to it.
5969 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
5970 ssh2_pkt_addstring(s
->pktout
, "ssh-userauth");
5971 ssh2_pkt_send(ssh
, s
->pktout
);
5972 crWaitUntilV(pktin
);
5973 if (pktin
->type
!= SSH2_MSG_SERVICE_ACCEPT
) {
5974 bombout(("Server refused user authentication protocol"));
5979 * We repeat this whole loop, including the username prompt,
5980 * until we manage a successful authentication. If the user
5981 * types the wrong _password_, they can be sent back to the
5982 * beginning to try another username, if this is configured on.
5983 * (If they specify a username in the config, they are never
5984 * asked, even if they do give a wrong password.)
5986 * I think this best serves the needs of
5988 * - the people who have no configuration, no keys, and just
5989 * want to try repeated (username,password) pairs until they
5990 * type both correctly
5992 * - people who have keys and configuration but occasionally
5993 * need to fall back to passwords
5995 * - people with a key held in Pageant, who might not have
5996 * logged in to a particular machine before; so they want to
5997 * type a username, and then _either_ their key will be
5998 * accepted, _or_ they will type a password. If they mistype
5999 * the username they will want to be able to get back and
6002 s
->username
[0] = '\0';
6003 s
->got_username
= FALSE
;
6008 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
6010 * We got a username last time round this loop, and
6011 * with change_username turned off we don't try to get
6014 } else if (!*ssh
->cfg
.username
) {
6015 if (ssh_get_line
&& !ssh_getline_pw_only
) {
6016 if (!ssh_get_line("login as: ",
6017 s
->username
, sizeof(s
->username
), FALSE
)) {
6019 * get_line failed to get a username.
6022 logevent("No username provided. Abandoning session.");
6023 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6027 int ret
; /* need not be saved across crReturn */
6028 c_write_str(ssh
, "login as: ");
6030 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
6032 crWaitUntilV(!pktin
);
6033 ret
= process_userpass_input(ssh
, in
, inlen
);
6037 c_write_str(ssh
, "\r\n");
6039 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
6042 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
6043 s
->username
[sizeof(s
->username
)-1] = '\0';
6044 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
6045 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
6046 c_write_str(ssh
, stuff
);
6050 s
->got_username
= TRUE
;
6053 * Send an authentication request using method "none": (a)
6054 * just in case it succeeds, and (b) so that we know what
6055 * authentication methods we can usefully try next.
6057 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6059 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6060 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6061 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");/* service requested */
6062 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6063 ssh2_pkt_send(ssh
, s
->pktout
);
6064 s
->type
= AUTH_TYPE_NONE
;
6066 s
->we_are_in
= FALSE
;
6068 s
->tried_pubkey_config
= FALSE
;
6069 s
->tried_agent
= FALSE
;
6070 s
->kbd_inter_running
= FALSE
;
6071 s
->kbd_inter_refused
= FALSE
;
6072 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
6073 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
6075 logeventf(ssh
, "Reading private key file \"%.150s\"",
6076 filename_to_str(&ssh
->cfg
.keyfile
));
6077 keytype
= key_type(&ssh
->cfg
.keyfile
);
6078 if (keytype
== SSH_KEYTYPE_SSH2
) {
6080 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
6081 &s
->publickey_bloblen
, NULL
);
6084 logeventf(ssh
, "Unable to use this key file (%s)",
6085 key_type_to_str(keytype
));
6086 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
6088 filename_to_str(&ssh
->cfg
.keyfile
),
6089 key_type_to_str(keytype
));
6090 c_write_str(ssh
, msgbuf
);
6092 s
->publickey_blob
= NULL
;
6095 s
->publickey_blob
= NULL
;
6099 * Wait for the result of the last authentication request.
6102 crWaitUntilV(pktin
);
6103 while (pktin
->type
== SSH2_MSG_USERAUTH_BANNER
) {
6107 * Don't show the banner if we're operating in
6108 * non-verbose non-interactive mode. (It's probably
6109 * a script, which means nobody will read the
6110 * banner _anyway_, and moreover the printing of
6111 * the banner will screw up processing on the
6112 * output of (say) plink.)
6114 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
6115 ssh_pkt_getstring(pktin
, &banner
, &size
);
6117 c_write_untrusted(ssh
, banner
, size
);
6119 crWaitUntilV(pktin
);
6121 if (pktin
->type
== SSH2_MSG_USERAUTH_SUCCESS
) {
6122 logevent("Access granted");
6123 s
->we_are_in
= TRUE
;
6127 if (s
->kbd_inter_running
&&
6128 pktin
->type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6130 * This is either a further set-of-prompts packet
6131 * in keyboard-interactive authentication, or it's
6132 * the same one and we came back here with `gotit'
6133 * set. In the former case, we must reset the
6134 * curr_prompt variable.
6138 } else if (pktin
->type
== SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
) {
6139 /* FIXME: perhaps we should support this? */
6140 bombout(("PASSWD_CHANGEREQ not yet supported"));
6142 } else if (pktin
->type
!= SSH2_MSG_USERAUTH_FAILURE
) {
6143 bombout(("Strange packet received during authentication: type %d",
6151 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6152 * we can look at the string in it and know what we can
6153 * helpfully try next.
6155 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
) {
6158 ssh_pkt_getstring(pktin
, &methods
, &methlen
);
6159 s
->kbd_inter_running
= FALSE
;
6160 if (!ssh2_pkt_getbool(pktin
)) {
6162 * We have received an unequivocal Access
6163 * Denied. This can translate to a variety of
6166 * - if we'd just tried "none" authentication,
6167 * it's not worth printing anything at all
6169 * - if we'd just tried a public key _offer_,
6170 * the message should be "Server refused our
6171 * key" (or no message at all if the key
6172 * came from Pageant)
6174 * - if we'd just tried anything else, the
6175 * message really should be "Access denied".
6177 * Additionally, if we'd just tried password
6178 * authentication, we should break out of this
6179 * whole loop so as to go back to the username
6180 * prompt (iff we're configured to allow
6181 * username change attempts).
6183 if (s
->type
== AUTH_TYPE_NONE
) {
6185 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
6186 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
6187 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
6188 c_write_str(ssh
, "Server refused our key\r\n");
6189 logevent("Server refused public key");
6190 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
6191 /* server declined keyboard-interactive; ignore */
6193 c_write_str(ssh
, "Access denied\r\n");
6194 logevent("Access denied");
6195 if (s
->type
== AUTH_TYPE_PASSWORD
&&
6196 ssh
->cfg
.change_username
) {
6197 /* XXX perhaps we should allow
6198 * keyboard-interactive to do this too? */
6199 s
->we_are_in
= FALSE
;
6204 c_write_str(ssh
, "Further authentication required\r\n");
6205 logevent("Further authentication required");
6209 in_commasep_string("publickey", methods
, methlen
);
6211 in_commasep_string("password", methods
, methlen
);
6212 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
6213 in_commasep_string("keyboard-interactive", methods
, methlen
);
6217 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6221 * Most password/passphrase prompts will be
6222 * non-echoing, so we set this to 0 by default.
6223 * Exception is that some keyboard-interactive prompts
6224 * can be echoing, in which case we'll set this to 1.
6228 if (!s
->method
&& s
->can_pubkey
&&
6229 agent_exists() && !s
->tried_agent
) {
6231 * Attempt public-key authentication using Pageant.
6236 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6237 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6239 s
->tried_agent
= TRUE
;
6241 logevent("Pageant is running. Requesting keys.");
6243 /* Request the keys held by the agent. */
6244 PUT_32BIT(s
->request
, 1);
6245 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
6246 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
6247 ssh_agent_callback
, ssh
)) {
6251 bombout(("Unexpected data from server while"
6252 " waiting for agent response"));
6255 } while (pktin
|| inlen
> 0);
6256 r
= ssh
->agent_response
;
6257 s
->responselen
= ssh
->agent_response_len
;
6259 s
->response
= (unsigned char *) r
;
6260 if (s
->response
&& s
->responselen
>= 5 &&
6261 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
6262 s
->p
= s
->response
+ 5;
6263 s
->nkeys
= GET_32BIT(s
->p
);
6267 sprintf(buf
, "Pageant has %d SSH2 keys", s
->nkeys
);
6270 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
6275 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
6278 s
->pklen
= GET_32BIT(s
->p
);
6280 if (s
->publickey_blob
&&
6281 s
->pklen
== s
->publickey_bloblen
&&
6282 !memcmp(s
->p
, s
->publickey_blob
,
6283 s
->publickey_bloblen
)) {
6284 logevent("This key matches configured key file");
6285 s
->tried_pubkey_config
= 1;
6287 s
->pkblob
= (char *)s
->p
;
6289 s
->alglen
= GET_32BIT(s
->pkblob
);
6290 s
->alg
= s
->pkblob
+ 4;
6291 s
->commentlen
= GET_32BIT(s
->p
);
6293 s
->commentp
= (char *)s
->p
;
6294 s
->p
+= s
->commentlen
;
6295 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6296 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6297 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6298 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6299 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6300 ssh2_pkt_addstring_start(s
->pktout
);
6301 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6302 ssh2_pkt_addstring_start(s
->pktout
);
6303 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6304 ssh2_pkt_send(ssh
, s
->pktout
);
6306 crWaitUntilV(pktin
);
6307 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6308 logevent("Key refused");
6312 if (flags
& FLAG_VERBOSE
) {
6313 c_write_str(ssh
, "Authenticating with "
6315 c_write(ssh
, s
->commentp
, s
->commentlen
);
6316 c_write_str(ssh
, "\" from agent\r\n");
6320 * Server is willing to accept the key.
6321 * Construct a SIGN_REQUEST.
6323 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6324 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6325 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6326 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6327 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6328 ssh2_pkt_addstring_start(s
->pktout
);
6329 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6330 ssh2_pkt_addstring_start(s
->pktout
);
6331 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6333 s
->siglen
= s
->pktout
->length
- 5 + 4 + 20;
6334 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6336 s
->len
= 1; /* message type */
6337 s
->len
+= 4 + s
->pklen
; /* key blob */
6338 s
->len
+= 4 + s
->siglen
; /* data to sign */
6339 s
->len
+= 4; /* flags */
6340 s
->agentreq
= snewn(4 + s
->len
, char);
6341 PUT_32BIT(s
->agentreq
, s
->len
);
6342 s
->q
= s
->agentreq
+ 4;
6343 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
6344 PUT_32BIT(s
->q
, s
->pklen
);
6346 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
6348 PUT_32BIT(s
->q
, s
->siglen
);
6350 /* Now the data to be signed... */
6351 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6352 PUT_32BIT(s
->q
, 20);
6355 memcpy(s
->q
, ssh
->v2_session_id
, 20);
6357 memcpy(s
->q
, s
->pktout
->data
+ 5,
6358 s
->pktout
->length
- 5);
6359 s
->q
+= s
->pktout
->length
- 5;
6360 /* And finally the (zero) flags word. */
6362 if (!agent_query(s
->agentreq
, s
->len
+ 4,
6364 ssh_agent_callback
, ssh
)) {
6368 bombout(("Unexpected data from server"
6369 " while waiting for agent"
6373 } while (pktin
|| inlen
> 0);
6374 vret
= ssh
->agent_response
;
6375 s
->retlen
= ssh
->agent_response_len
;
6380 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
6381 logevent("Sending Pageant's response");
6382 ssh2_add_sigblob(ssh
, s
->pktout
,
6383 s
->pkblob
, s
->pklen
,
6385 GET_32BIT(s
->ret
+ 5));
6386 ssh2_pkt_send(ssh
, s
->pktout
);
6391 ("Pageant failed to answer challenge");
6402 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
6403 && !s
->tried_pubkey_config
) {
6404 unsigned char *pub_blob
;
6405 char *algorithm
, *comment
;
6408 s
->tried_pubkey_config
= TRUE
;
6410 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6411 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6414 * Try the public key supplied in the configuration.
6416 * First, offer the public blob to see if the server is
6417 * willing to accept it.
6420 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
6425 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6426 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6427 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6428 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6429 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6430 ssh2_pkt_addstring(s
->pktout
, algorithm
);
6431 ssh2_pkt_addstring_start(s
->pktout
);
6432 ssh2_pkt_addstring_data(s
->pktout
, (char *)pub_blob
,
6434 ssh2_pkt_send(ssh
, s
->pktout
);
6435 logevent("Offered public key");
6437 crWaitUntilV(pktin
);
6438 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6440 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
6441 continue; /* key refused; give up on it */
6444 logevent("Offer of public key accepted");
6446 * Actually attempt a serious authentication using
6449 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
6450 sprintf(s
->pwprompt
,
6451 "Passphrase for key \"%.100s\": ",
6457 if (flags
& FLAG_VERBOSE
) {
6458 c_write_str(ssh
, "Authenticating with public key \"");
6459 c_write_str(ssh
, comment
);
6460 c_write_str(ssh
, "\"\r\n");
6462 s
->method
= AUTH_PUBLICKEY_FILE
;
6466 if (!s
->method
&& s
->can_keyb_inter
&& !s
->kbd_inter_refused
&&
6467 !s
->kbd_inter_running
) {
6468 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6469 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6471 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6472 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6474 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6475 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6476 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6477 ssh2_pkt_addstring(s
->pktout
, "keyboard-interactive"); /* method */
6478 ssh2_pkt_addstring(s
->pktout
, ""); /* lang */
6479 ssh2_pkt_addstring(s
->pktout
, "");
6480 ssh2_pkt_send(ssh
, s
->pktout
);
6482 crWaitUntilV(pktin
);
6483 if (pktin
->type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6484 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
)
6486 logevent("Keyboard-interactive authentication refused");
6487 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
6488 s
->kbd_inter_refused
= TRUE
; /* don't try it again */
6492 s
->kbd_inter_running
= TRUE
;
6496 if (s
->kbd_inter_running
) {
6497 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6498 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6500 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6501 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6503 if (s
->curr_prompt
== 0) {
6505 * We've got a fresh USERAUTH_INFO_REQUEST.
6506 * Display header data, and start going through
6509 char *name
, *inst
, *lang
;
6510 int name_len
, inst_len
, lang_len
;
6512 ssh_pkt_getstring(pktin
, &name
, &name_len
);
6513 ssh_pkt_getstring(pktin
, &inst
, &inst_len
);
6514 ssh_pkt_getstring(pktin
, &lang
, &lang_len
);
6516 c_write_untrusted(ssh
, name
, name_len
);
6517 c_write_str(ssh
, "\r\n");
6520 c_write_untrusted(ssh
, inst
, inst_len
);
6521 c_write_str(ssh
, "\r\n");
6523 s
->num_prompts
= ssh_pkt_getuint32(pktin
);
6527 * If there are prompts remaining in the packet,
6528 * display one and get a response.
6530 if (s
->curr_prompt
< s
->num_prompts
) {
6534 ssh_pkt_getstring(pktin
, &prompt
, &prompt_len
);
6535 if (prompt_len
> 0) {
6536 static const char trunc
[] = "<prompt truncated>: ";
6537 static const int prlen
= sizeof(s
->pwprompt
) -
6539 if (prompt_len
> prlen
) {
6540 memcpy(s
->pwprompt
, prompt
, prlen
);
6541 strcpy(s
->pwprompt
+ prlen
, trunc
);
6543 memcpy(s
->pwprompt
, prompt
, prompt_len
);
6544 s
->pwprompt
[prompt_len
] = '\0';
6548 "<server failed to send prompt>: ");
6550 s
->echo
= ssh2_pkt_getbool(pktin
);
6556 if (!s
->method
&& s
->can_passwd
) {
6557 s
->method
= AUTH_PASSWORD
;
6558 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6559 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
6560 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
6567 if (!ssh_get_line(s
->pwprompt
, s
->password
,
6568 sizeof(s
->password
), TRUE
)) {
6570 * get_line failed to get a password (for
6571 * example because one was supplied on the
6572 * command line which has already failed to
6575 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6576 ssh2_pkt_adduint32(s
->pktout
,SSH2_DISCONNECT_BY_APPLICATION
);
6577 ssh2_pkt_addstring(s
->pktout
, "No more passwords available"
6579 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6580 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6581 logevent("Unable to authenticate");
6582 connection_fatal(ssh
->frontend
,
6583 "Unable to authenticate");
6584 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6588 int ret
; /* need not be saved across crReturn */
6589 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
6592 setup_userpass_input(ssh
, s
->password
,
6593 sizeof(s
->password
), s
->echo
);
6595 crWaitUntilV(!pktin
);
6596 ret
= process_userpass_input(ssh
, in
, inlen
);
6600 c_write_str(ssh
, "\r\n");
6604 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
6606 * We have our passphrase. Now try the actual authentication.
6608 struct ssh2_userkey
*key
;
6609 const char *error
= NULL
;
6611 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
,
6613 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
6614 if (key
== SSH2_WRONG_PASSPHRASE
) {
6615 c_write_str(ssh
, "Wrong passphrase\r\n");
6616 s
->tried_pubkey_config
= FALSE
;
6618 c_write_str(ssh
, "Unable to load private key (");
6619 c_write_str(ssh
, error
);
6620 c_write_str(ssh
, ")\r\n");
6621 s
->tried_pubkey_config
= TRUE
;
6623 /* Send a spurious AUTH_NONE to return to the top. */
6624 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6625 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6626 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6627 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6628 ssh2_pkt_send(ssh
, s
->pktout
);
6629 s
->type
= AUTH_TYPE_NONE
;
6631 unsigned char *pkblob
, *sigblob
, *sigdata
;
6632 int pkblob_len
, sigblob_len
, sigdata_len
;
6636 * We have loaded the private key and the server
6637 * has announced that it's willing to accept it.
6638 * Hallelujah. Generate a signature and send it.
6640 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6641 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6642 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6643 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6644 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6645 ssh2_pkt_addstring(s
->pktout
, key
->alg
->name
);
6646 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
6647 ssh2_pkt_addstring_start(s
->pktout
);
6648 ssh2_pkt_addstring_data(s
->pktout
, (char *)pkblob
, pkblob_len
);
6651 * The data to be signed is:
6655 * followed by everything so far placed in the
6658 sigdata_len
= s
->pktout
->length
- 5 + 4 + 20;
6659 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6661 sigdata
= snewn(sigdata_len
, unsigned char);
6663 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6664 PUT_32BIT(sigdata
+p
, 20);
6667 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
6668 memcpy(sigdata
+p
, s
->pktout
->data
+ 5,
6669 s
->pktout
->length
- 5);
6670 p
+= s
->pktout
->length
- 5;
6671 assert(p
== sigdata_len
);
6672 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
6673 sigdata_len
, &sigblob_len
);
6674 ssh2_add_sigblob(ssh
, s
->pktout
, pkblob
, pkblob_len
,
6675 sigblob
, sigblob_len
);
6680 ssh2_pkt_send(ssh
, s
->pktout
);
6681 s
->type
= AUTH_TYPE_PUBLICKEY
;
6682 key
->alg
->freekey(key
->data
);
6684 } else if (s
->method
== AUTH_PASSWORD
) {
6686 * We send the password packet lumped tightly together with
6687 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
6688 * string long enough to make the total length of the two
6689 * packets constant. This should ensure that a passive
6690 * listener doing traffic analyis can't work out the length
6693 * For this to work, we need an assumption about the
6694 * maximum length of the password packet. I think 256 is
6695 * pretty conservative. Anyone using a password longer than
6696 * that probably doesn't have much to worry about from
6697 * people who find out how long their password is!
6699 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6700 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6701 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6702 ssh2_pkt_addstring(s
->pktout
, "password");
6703 ssh2_pkt_addbool(s
->pktout
, FALSE
);
6704 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6705 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6706 memset(s
->password
, 0, sizeof(s
->password
));
6707 end_log_omission(ssh
, s
->pktout
);
6708 ssh2_pkt_defer(ssh
, s
->pktout
);
6710 * We'll include a string that's an exact multiple of the
6711 * cipher block size. If the cipher is NULL for some
6712 * reason, we don't do this trick at all because we gain
6715 if (ssh
->cscipher
) {
6718 stringlen
= (256 - ssh
->deferred_len
);
6719 stringlen
+= ssh
->cscipher
->blksize
- 1;
6720 stringlen
-= (stringlen
% ssh
->cscipher
->blksize
);
6723 * Temporarily disable actual compression,
6724 * so we can guarantee to get this string
6725 * exactly the length we want it. The
6726 * compression-disabling routine should
6727 * return an integer indicating how many
6728 * bytes we should adjust our string length
6732 ssh
->cscomp
->disable_compression(ssh
->cs_comp_ctx
);
6734 s
->pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
6735 ssh2_pkt_addstring_start(s
->pktout
);
6736 for (i
= 0; i
< stringlen
; i
++) {
6737 char c
= (char) random_byte();
6738 ssh2_pkt_addstring_data(s
->pktout
, &c
, 1);
6740 ssh2_pkt_defer(ssh
, s
->pktout
);
6742 ssh_pkt_defersend(ssh
);
6743 logevent("Sent password");
6744 s
->type
= AUTH_TYPE_PASSWORD
;
6745 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
6746 if (s
->curr_prompt
== 0) {
6747 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
6748 ssh2_pkt_adduint32(s
->pktout
, s
->num_prompts
);
6750 if (s
->need_pw
) { /* only add pw if we just got one! */
6751 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6752 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6753 memset(s
->password
, 0, sizeof(s
->password
));
6754 end_log_omission(ssh
, s
->pktout
);
6757 if (s
->curr_prompt
>= s
->num_prompts
) {
6758 ssh2_pkt_send(ssh
, s
->pktout
);
6761 * If there are prompts remaining, we set
6762 * `gotit' so that we won't attempt to get
6763 * another packet. Then we go back round the
6764 * loop and will end up retrieving another
6765 * prompt out of the existing packet. Funky or
6770 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6772 c_write_str(ssh
, "No supported authentication methods"
6773 " left to try!\r\n");
6774 logevent("No supported authentications offered."
6776 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6777 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
6778 ssh2_pkt_addstring(s
->pktout
, "No supported authentication"
6779 " methods available");
6780 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6781 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6782 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6786 } while (!s
->we_are_in
);
6789 * Now we're authenticated for the connection protocol. The
6790 * connection protocol will automatically have started at this
6791 * point; there's no need to send SERVICE_REQUEST.
6794 ssh
->channels
= newtree234(ssh_channelcmp
);
6797 * Set up handlers for some connection protocol messages, so we
6798 * don't have to handle them repeatedly in this coroutine.
6800 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] =
6801 ssh2_msg_channel_window_adjust
;
6802 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] =
6803 ssh2_msg_global_request
;
6806 * Create the main session channel.
6808 if (!ssh
->cfg
.ssh_no_shell
) {
6809 ssh
->mainchan
= snew(struct ssh_channel
);
6810 ssh
->mainchan
->ssh
= ssh
;
6811 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
6812 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
6813 ssh2_pkt_addstring(s
->pktout
, "session");
6814 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->localid
);
6815 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6816 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
6817 ssh2_pkt_adduint32(s
->pktout
, 0x4000UL
); /* our max pkt size */
6818 ssh2_pkt_send(ssh
, s
->pktout
);
6819 crWaitUntilV(pktin
);
6820 if (pktin
->type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
6821 bombout(("Server refused to open a session"));
6823 /* FIXME: error data comes back in FAILURE packet */
6825 if (ssh_pkt_getuint32(pktin
) != ssh
->mainchan
->localid
) {
6826 bombout(("Server's channel confirmation cited wrong channel"));
6829 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(pktin
);
6830 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
6831 ssh
->mainchan
->closes
= 0;
6832 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
6833 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
6834 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
6835 add234(ssh
->channels
, ssh
->mainchan
);
6836 update_specials_menu(ssh
->frontend
);
6837 logevent("Opened channel for session");
6839 ssh
->mainchan
= NULL
;
6842 * Now we have a channel, make dispatch table entries for
6843 * general channel-based messages.
6845 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] =
6846 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] =
6847 ssh2_msg_channel_data
;
6848 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = ssh2_msg_channel_eof
;
6849 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = ssh2_msg_channel_close
;
6850 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] =
6851 ssh2_msg_channel_open_confirmation
;
6852 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] =
6853 ssh2_msg_channel_open_failure
;
6854 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] =
6855 ssh2_msg_channel_request
;
6856 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] =
6857 ssh2_msg_channel_open
;
6860 * Potentially enable X11 forwarding.
6862 if (ssh
->mainchan
&& ssh
->cfg
.x11_forward
) {
6863 char proto
[20], data
[64];
6864 logevent("Requesting X11 forwarding");
6865 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
6866 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
6867 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
6868 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6869 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6870 ssh2_pkt_addstring(s
->pktout
, "x11-req");
6871 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6872 ssh2_pkt_addbool(s
->pktout
, 0); /* many connections */
6873 ssh2_pkt_addstring(s
->pktout
, proto
);
6874 ssh2_pkt_addstring(s
->pktout
, data
);
6875 ssh2_pkt_adduint32(s
->pktout
, x11_get_screen_number(ssh
->cfg
.x11_display
));
6876 ssh2_pkt_send(ssh
, s
->pktout
);
6878 crWaitUntilV(pktin
);
6880 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6881 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6882 bombout(("Unexpected response to X11 forwarding request:"
6883 " packet type %d", pktin
->type
));
6886 logevent("X11 forwarding refused");
6888 logevent("X11 forwarding enabled");
6889 ssh
->X11_fwd_enabled
= TRUE
;
6894 * Enable port forwardings.
6896 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
6899 * Potentially enable agent forwarding.
6901 if (ssh
->mainchan
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
6902 logevent("Requesting OpenSSH-style agent forwarding");
6903 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6904 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6905 ssh2_pkt_addstring(s
->pktout
, "auth-agent-req@openssh.com");
6906 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6907 ssh2_pkt_send(ssh
, s
->pktout
);
6909 crWaitUntilV(pktin
);
6911 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6912 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6913 bombout(("Unexpected response to agent forwarding request:"
6914 " packet type %d", pktin
->type
));
6917 logevent("Agent forwarding refused");
6919 logevent("Agent forwarding enabled");
6920 ssh
->agentfwd_enabled
= TRUE
;
6925 * Now allocate a pty for the session.
6927 if (ssh
->mainchan
&& !ssh
->cfg
.nopty
) {
6928 /* Unpick the terminal-speed string. */
6929 /* XXX perhaps we should allow no speeds to be sent. */
6930 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
6931 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
6932 /* Build the pty request. */
6933 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6934 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
6935 ssh2_pkt_addstring(s
->pktout
, "pty-req");
6936 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6937 ssh2_pkt_addstring(s
->pktout
, ssh
->cfg
.termtype
);
6938 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_width
);
6939 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_height
);
6940 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel width */
6941 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel height */
6942 ssh2_pkt_addstring_start(s
->pktout
);
6943 ssh2_pkt_addbyte(s
->pktout
, 128); /* TTY_OP_ISPEED */
6944 ssh2_pkt_adduint32(s
->pktout
, ssh
->ispeed
);
6945 ssh2_pkt_addbyte(s
->pktout
, 129); /* TTY_OP_OSPEED */
6946 ssh2_pkt_adduint32(s
->pktout
, ssh
->ospeed
);
6947 ssh2_pkt_addstring_data(s
->pktout
, "\0", 1); /* TTY_OP_END */
6948 ssh2_pkt_send(ssh
, s
->pktout
);
6949 ssh
->state
= SSH_STATE_INTERMED
;
6951 crWaitUntilV(pktin
);
6953 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6954 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6955 bombout(("Unexpected response to pty request:"
6956 " packet type %d", pktin
->type
));
6959 c_write_str(ssh
, "Server refused to allocate pty\r\n");
6960 ssh
->editing
= ssh
->echoing
= 1;
6962 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
6963 ssh
->ospeed
, ssh
->ispeed
);
6966 ssh
->editing
= ssh
->echoing
= 1;
6970 * Send environment variables.
6972 * Simplest thing here is to send all the requests at once, and
6973 * then wait for a whole bunch of successes or failures.
6975 if (ssh
->mainchan
&& *ssh
->cfg
.environmt
) {
6976 char *e
= ssh
->cfg
.environmt
;
6977 char *var
, *varend
, *val
;
6983 while (*e
&& *e
!= '\t') e
++;
6985 if (*e
== '\t') e
++;
6990 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6991 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6992 ssh2_pkt_addstring(s
->pktout
, "env");
6993 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6994 ssh2_pkt_addstring_start(s
->pktout
);
6995 ssh2_pkt_addstring_data(s
->pktout
, var
, varend
-var
);
6996 ssh2_pkt_addstring(s
->pktout
, val
);
6997 ssh2_pkt_send(ssh
, s
->pktout
);
7002 logeventf(ssh
, "Sent %d environment variables", s
->num_env
);
7005 s
->env_left
= s
->num_env
;
7007 while (s
->env_left
> 0) {
7008 crWaitUntilV(pktin
);
7010 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7011 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7012 bombout(("Unexpected response to environment request:"
7013 " packet type %d", pktin
->type
));
7023 if (s
->env_ok
== s
->num_env
) {
7024 logevent("All environment variables successfully set");
7025 } else if (s
->env_ok
== 0) {
7026 logevent("All environment variables refused");
7027 c_write_str(ssh
, "Server refused to set environment variables\r\n");
7029 logeventf(ssh
, "%d environment variables refused",
7030 s
->num_env
- s
->env_ok
);
7031 c_write_str(ssh
, "Server refused to set all environment variables\r\n");
7036 * Start a shell or a remote command. We may have to attempt
7037 * this twice if the config data has provided a second choice
7040 if (ssh
->mainchan
) while (1) {
7044 if (ssh
->fallback_cmd
) {
7045 subsys
= ssh
->cfg
.ssh_subsys2
;
7046 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
7048 subsys
= ssh
->cfg
.ssh_subsys
;
7049 cmd
= ssh
->cfg
.remote_cmd_ptr
;
7052 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7053 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7055 ssh2_pkt_addstring(s
->pktout
, "subsystem");
7056 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7057 ssh2_pkt_addstring(s
->pktout
, cmd
);
7059 ssh2_pkt_addstring(s
->pktout
, "exec");
7060 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7061 ssh2_pkt_addstring(s
->pktout
, cmd
);
7063 ssh2_pkt_addstring(s
->pktout
, "shell");
7064 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7066 ssh2_pkt_send(ssh
, s
->pktout
);
7068 crWaitUntilV(pktin
);
7070 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7071 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7072 bombout(("Unexpected response to shell/command request:"
7073 " packet type %d", pktin
->type
));
7077 * We failed to start the command. If this is the
7078 * fallback command, we really are finished; if it's
7079 * not, and if the fallback command exists, try falling
7080 * back to it before complaining.
7082 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
7083 logevent("Primary command failed; attempting fallback");
7084 ssh
->fallback_cmd
= TRUE
;
7087 bombout(("Server refused to start a shell/command"));
7090 logevent("Started a shell/command");
7095 ssh
->state
= SSH_STATE_SESSION
;
7096 if (ssh
->size_needed
)
7097 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
7098 if (ssh
->eof_needed
)
7099 ssh_special(ssh
, TS_EOF
);
7105 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
7110 s
->try_send
= FALSE
;
7114 * _All_ the connection-layer packets we expect to
7115 * receive are now handled by the dispatch table.
7116 * Anything that reaches here must be bogus.
7119 bombout(("Strange packet received: type %d", pktin
->type
));
7121 } else if (ssh
->mainchan
) {
7123 * We have spare data. Add it to the channel buffer.
7125 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
7130 struct ssh_channel
*c
;
7132 * Try to send data on all channels if we can.
7134 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
7137 continue; /* don't send on closing channels */
7138 bufsize
= ssh2_try_send(c
);
7141 case CHAN_MAINSESSION
:
7142 /* stdin need not receive an unthrottle
7143 * notification since it will be polled */
7146 x11_unthrottle(c
->u
.x11
.s
);
7149 /* agent sockets are request/response and need no
7150 * buffer management */
7153 pfd_unthrottle(c
->u
.pfd
.s
);
7165 * Handlers for SSH2 messages that might arrive at any moment.
7167 void ssh2_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
7169 /* log reason code in disconnect message */
7171 int nowlen
, reason
, msglen
;
7173 reason
= ssh_pkt_getuint32(pktin
);
7174 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7176 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
7177 buf
= dupprintf("Received disconnect message (%s)",
7178 ssh2_disconnect_reasons
[reason
]);
7180 buf
= dupprintf("Received disconnect message (unknown"
7181 " type %d)", reason
);
7185 buf
= dupprintf("Disconnection message text: %n%.*s",
7186 &nowlen
, msglen
, msg
);
7188 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7190 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
7191 ssh2_disconnect_reasons
[reason
] : "unknown",
7196 void ssh2_msg_debug(Ssh ssh
, struct Packet
*pktin
)
7198 /* log the debug message */
7203 /* XXX maybe we should actually take notice of this */
7204 always_display
= ssh2_pkt_getbool(pktin
);
7205 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7207 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
7212 void ssh2_msg_something_unimplemented(Ssh ssh
, struct Packet
*pktin
)
7214 struct Packet
*pktout
;
7215 pktout
= ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
7216 ssh2_pkt_adduint32(pktout
, pktin
->sequence
);
7218 * UNIMPLEMENTED messages MUST appear in the same order as the
7219 * messages they respond to. Hence, never queue them.
7221 ssh2_pkt_send_noqueue(ssh
, pktout
);
7225 * Handle the top-level SSH2 protocol.
7227 static void ssh2_protocol_setup(Ssh ssh
)
7232 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7234 for (i
= 0; i
< 256; i
++)
7235 ssh
->packet_dispatch
[i
] = ssh2_msg_something_unimplemented
;
7238 * Any message we actually understand, we set to NULL so that
7239 * the coroutines will get it.
7241 ssh
->packet_dispatch
[SSH2_MSG_UNIMPLEMENTED
] = NULL
;
7242 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_REQUEST
] = NULL
;
7243 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_ACCEPT
] = NULL
;
7244 ssh
->packet_dispatch
[SSH2_MSG_KEXINIT
] = NULL
;
7245 ssh
->packet_dispatch
[SSH2_MSG_NEWKEYS
] = NULL
;
7246 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_INIT
] = NULL
;
7247 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_REPLY
] = NULL
;
7248 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7249 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7250 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_INIT
] = NULL
;
7251 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_REPLY
] = NULL
;
7252 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_REQUEST
] = NULL
;
7253 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_FAILURE
] = NULL
;
7254 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_SUCCESS
] = NULL
;
7255 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
7256 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_PK_OK
] = NULL
;
7257 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7258 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7259 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_INFO_RESPONSE
] = NULL
;
7260 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] = NULL
;
7261 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_SUCCESS
] = NULL
;
7262 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_FAILURE
] = NULL
;
7263 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] = NULL
;
7264 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] = NULL
;
7265 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] = NULL
;
7266 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] = NULL
;
7267 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] = NULL
;
7268 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] = NULL
;
7269 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = NULL
;
7270 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = NULL
;
7271 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] = NULL
;
7272 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_SUCCESS
] = NULL
;
7273 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_FAILURE
] = NULL
;
7276 * These special message types we install handlers for.
7278 ssh
->packet_dispatch
[SSH2_MSG_DISCONNECT
] = ssh2_msg_disconnect
;
7279 ssh
->packet_dispatch
[SSH2_MSG_IGNORE
] = ssh_msg_ignore
; /* shared with ssh1 */
7280 ssh
->packet_dispatch
[SSH2_MSG_DEBUG
] = ssh2_msg_debug
;
7283 static void ssh2_timer(void *ctx
, long now
)
7287 if (!ssh
->kex_in_progress
&& ssh
->cfg
.ssh_rekey_time
!= 0 &&
7288 now
- ssh
->next_rekey
>= 0) {
7289 do_ssh2_transport(ssh
, "Initiating key re-exchange (timeout)",
7294 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
7295 struct Packet
*pktin
)
7297 if (ssh
->state
== SSH_STATE_CLOSED
)
7301 ssh
->incoming_data_size
+= pktin
->encrypted_len
;
7302 if (!ssh
->kex_in_progress
&&
7303 ssh
->max_data_size
!= 0 &&
7304 ssh
->incoming_data_size
> ssh
->max_data_size
)
7305 do_ssh2_transport(ssh
, "Initiating key re-exchange "
7306 "(too much data received)", -1, NULL
);
7309 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
7310 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
7314 if (!ssh
->protocol_initial_phase_done
||
7315 (pktin
&& pktin
->type
>= 20 && pktin
->type
< 50)) {
7316 if (do_ssh2_transport(ssh
, in
, inlen
, pktin
) &&
7317 !ssh
->protocol_initial_phase_done
) {
7318 ssh
->protocol_initial_phase_done
= TRUE
;
7320 * Allow authconn to initialise itself.
7322 do_ssh2_authconn(ssh
, NULL
, 0, NULL
);
7325 do_ssh2_authconn(ssh
, in
, inlen
, pktin
);
7330 * Called to set up the connection.
7332 * Returns an error message, or NULL on success.
7334 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
7336 char *host
, int port
, char **realhost
, int nodelay
,
7342 ssh
= snew(struct ssh_tag
);
7343 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7344 ssh
->version
= 0; /* when not ready yet */
7347 ssh
->v1_cipher_ctx
= NULL
;
7348 ssh
->crcda_ctx
= NULL
;
7349 ssh
->cscipher
= NULL
;
7350 ssh
->cs_cipher_ctx
= NULL
;
7351 ssh
->sccipher
= NULL
;
7352 ssh
->sc_cipher_ctx
= NULL
;
7354 ssh
->cs_mac_ctx
= NULL
;
7356 ssh
->sc_mac_ctx
= NULL
;
7358 ssh
->cs_comp_ctx
= NULL
;
7360 ssh
->sc_comp_ctx
= NULL
;
7362 ssh
->kex_ctx
= NULL
;
7363 ssh
->hostkey
= NULL
;
7365 ssh
->state
= SSH_STATE_PREPACKET
;
7366 ssh
->size_needed
= FALSE
;
7367 ssh
->eof_needed
= FALSE
;
7370 ssh
->deferred_send_data
= NULL
;
7371 ssh
->deferred_len
= 0;
7372 ssh
->deferred_size
= 0;
7373 ssh
->fallback_cmd
= 0;
7375 ssh
->x11auth
= NULL
;
7376 ssh
->v1_compressing
= FALSE
;
7377 ssh
->v2_outgoing_sequence
= 0;
7378 ssh
->ssh1_rdpkt_crstate
= 0;
7379 ssh
->ssh2_rdpkt_crstate
= 0;
7380 ssh
->do_ssh_init_crstate
= 0;
7381 ssh
->ssh_gotdata_crstate
= 0;
7382 ssh
->do_ssh1_connection_crstate
= 0;
7383 ssh
->do_ssh1_login_crstate
= 0;
7384 ssh
->do_ssh2_transport_crstate
= 0;
7385 ssh
->do_ssh2_authconn_crstate
= 0;
7386 ssh
->do_ssh_init_state
= NULL
;
7387 ssh
->do_ssh1_login_state
= NULL
;
7388 ssh
->do_ssh2_transport_state
= NULL
;
7389 ssh
->do_ssh2_authconn_state
= NULL
;
7390 ssh
->mainchan
= NULL
;
7391 ssh
->throttled_all
= 0;
7392 ssh
->v1_stdout_throttling
= 0;
7394 ssh
->queuelen
= ssh
->queuesize
= 0;
7395 ssh
->queueing
= FALSE
;
7396 ssh
->qhead
= ssh
->qtail
= NULL
;
7397 ssh
->deferred_rekey_reason
= NULL
;
7399 *backend_handle
= ssh
;
7402 if (crypto_startup() == 0)
7403 return "Microsoft high encryption pack not installed!";
7406 ssh
->frontend
= frontend_handle
;
7407 ssh
->term_width
= ssh
->cfg
.width
;
7408 ssh
->term_height
= ssh
->cfg
.height
;
7410 ssh
->channels
= NULL
;
7411 ssh
->rportfwds
= NULL
;
7412 ssh
->portfwds
= NULL
;
7417 ssh
->v1_throttle_count
= 0;
7418 ssh
->overall_bufsize
= 0;
7419 ssh
->fallback_cmd
= 0;
7421 ssh
->protocol
= NULL
;
7423 ssh
->protocol_initial_phase_done
= FALSE
;
7427 ssh
->incoming_data_size
= ssh
->outgoing_data_size
=
7428 ssh
->deferred_data_size
= 0L;
7429 ssh
->max_data_size
= parse_blocksize(ssh
->cfg
.ssh_rekey_data
);
7430 ssh
->kex_in_progress
= FALSE
;
7432 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
7441 static void ssh_free(void *handle
)
7443 Ssh ssh
= (Ssh
) handle
;
7444 struct ssh_channel
*c
;
7445 struct ssh_rportfwd
*pf
;
7447 if (ssh
->v1_cipher_ctx
)
7448 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
7449 if (ssh
->cs_cipher_ctx
)
7450 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
7451 if (ssh
->sc_cipher_ctx
)
7452 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
7453 if (ssh
->cs_mac_ctx
)
7454 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
7455 if (ssh
->sc_mac_ctx
)
7456 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
7457 if (ssh
->cs_comp_ctx
) {
7459 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
7461 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
7463 if (ssh
->sc_comp_ctx
) {
7465 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
7467 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
7470 dh_cleanup(ssh
->kex_ctx
);
7471 sfree(ssh
->savedhost
);
7473 while (ssh
->queuelen
-- > 0)
7474 ssh_free_packet(ssh
->queue
[ssh
->queuelen
]);
7477 while (ssh
->qhead
) {
7478 struct queued_handler
*qh
= ssh
->qhead
;
7479 ssh
->qhead
= qh
->next
;
7482 ssh
->qhead
= ssh
->qtail
= NULL
;
7484 if (ssh
->channels
) {
7485 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
7488 if (c
->u
.x11
.s
!= NULL
)
7489 x11_close(c
->u
.x11
.s
);
7492 if (c
->u
.pfd
.s
!= NULL
)
7493 pfd_close(c
->u
.pfd
.s
);
7498 freetree234(ssh
->channels
);
7499 ssh
->channels
= NULL
;
7502 if (ssh
->rportfwds
) {
7503 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
7505 freetree234(ssh
->rportfwds
);
7506 ssh
->rportfwds
= NULL
;
7508 sfree(ssh
->deferred_send_data
);
7510 x11_free_auth(ssh
->x11auth
);
7511 sfree(ssh
->do_ssh_init_state
);
7512 sfree(ssh
->do_ssh1_login_state
);
7513 sfree(ssh
->do_ssh2_transport_state
);
7514 sfree(ssh
->do_ssh2_authconn_state
);
7515 if (ssh
->crcda_ctx
) {
7516 crcda_free_context(ssh
->crcda_ctx
);
7517 ssh
->crcda_ctx
= NULL
;
7521 expire_timer_context(ssh
);
7523 pinger_free(ssh
->pinger
);
7530 * Reconfigure the SSH backend.
7532 static void ssh_reconfig(void *handle
, Config
*cfg
)
7534 Ssh ssh
= (Ssh
) handle
;
7535 char *rekeying
= NULL
, rekey_mandatory
= FALSE
;
7536 unsigned long old_max_data_size
;
7538 pinger_reconfig(ssh
->pinger
, &ssh
->cfg
, cfg
);
7539 ssh_setup_portfwd(ssh
, cfg
);
7541 if (ssh
->cfg
.ssh_rekey_time
!= cfg
->ssh_rekey_time
&&
7542 cfg
->ssh_rekey_time
!= 0) {
7543 long new_next
= ssh
->last_rekey
+ cfg
->ssh_rekey_time
*60*TICKSPERSEC
;
7544 long now
= GETTICKCOUNT();
7546 if (new_next
- now
< 0) {
7547 rekeying
= "Initiating key re-exchange (timeout shortened)";
7549 ssh
->next_rekey
= schedule_timer(new_next
- now
, ssh2_timer
, ssh
);
7553 old_max_data_size
= ssh
->max_data_size
;
7554 ssh
->max_data_size
= parse_blocksize(cfg
->ssh_rekey_data
);
7555 if (old_max_data_size
!= ssh
->max_data_size
&&
7556 ssh
->max_data_size
!= 0) {
7557 if (ssh
->outgoing_data_size
> ssh
->max_data_size
||
7558 ssh
->incoming_data_size
> ssh
->max_data_size
)
7559 rekeying
= "Initiating key re-exchange (data limit lowered)";
7562 if (ssh
->cfg
.compression
!= cfg
->compression
) {
7563 rekeying
= "Initiating key re-exchange (compression setting changed)";
7564 rekey_mandatory
= TRUE
;
7567 if (ssh
->cfg
.ssh2_des_cbc
!= cfg
->ssh2_des_cbc
||
7568 memcmp(ssh
->cfg
.ssh_cipherlist
, cfg
->ssh_cipherlist
,
7569 sizeof(ssh
->cfg
.ssh_cipherlist
))) {
7570 rekeying
= "Initiating key re-exchange (cipher settings changed)";
7571 rekey_mandatory
= TRUE
;
7574 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7577 if (!ssh
->kex_in_progress
) {
7578 do_ssh2_transport(ssh
, rekeying
, -1, NULL
);
7579 } else if (rekey_mandatory
) {
7580 ssh
->deferred_rekey_reason
= rekeying
;
7586 * Called to send data down the Telnet connection.
7588 static int ssh_send(void *handle
, char *buf
, int len
)
7590 Ssh ssh
= (Ssh
) handle
;
7592 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7595 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
7597 return ssh_sendbuffer(ssh
);
7601 * Called to query the current amount of buffered stdin data.
7603 static int ssh_sendbuffer(void *handle
)
7605 Ssh ssh
= (Ssh
) handle
;
7608 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7612 * If the SSH socket itself has backed up, add the total backup
7613 * size on that to any individual buffer on the stdin channel.
7616 if (ssh
->throttled_all
)
7617 override_value
= ssh
->overall_bufsize
;
7619 if (ssh
->version
== 1) {
7620 return override_value
;
7621 } else if (ssh
->version
== 2) {
7622 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
7623 return override_value
;
7625 return (override_value
+
7626 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
7633 * Called to set the size of the window from SSH's POV.
7635 static void ssh_size(void *handle
, int width
, int height
)
7637 Ssh ssh
= (Ssh
) handle
;
7638 struct Packet
*pktout
;
7640 ssh
->term_width
= width
;
7641 ssh
->term_height
= height
;
7643 switch (ssh
->state
) {
7644 case SSH_STATE_BEFORE_SIZE
:
7645 case SSH_STATE_PREPACKET
:
7646 case SSH_STATE_CLOSED
:
7647 break; /* do nothing */
7648 case SSH_STATE_INTERMED
:
7649 ssh
->size_needed
= TRUE
; /* buffer for later */
7651 case SSH_STATE_SESSION
:
7652 if (!ssh
->cfg
.nopty
) {
7653 if (ssh
->version
== 1) {
7654 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
7655 PKT_INT
, ssh
->term_height
,
7656 PKT_INT
, ssh
->term_width
,
7657 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
7658 } else if (ssh
->mainchan
) {
7659 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7660 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7661 ssh2_pkt_addstring(pktout
, "window-change");
7662 ssh2_pkt_addbool(pktout
, 0);
7663 ssh2_pkt_adduint32(pktout
, ssh
->term_width
);
7664 ssh2_pkt_adduint32(pktout
, ssh
->term_height
);
7665 ssh2_pkt_adduint32(pktout
, 0);
7666 ssh2_pkt_adduint32(pktout
, 0);
7667 ssh2_pkt_send(ssh
, pktout
);
7675 * Return a list of the special codes that make sense in this
7678 static const struct telnet_special
*ssh_get_specials(void *handle
)
7680 static const struct telnet_special ssh1_ignore_special
[] = {
7681 {"IGNORE message", TS_NOP
}
7683 static const struct telnet_special ssh2_transport_specials
[] = {
7684 {"IGNORE message", TS_NOP
},
7685 {"Repeat key exchange", TS_REKEY
},
7687 static const struct telnet_special ssh2_session_specials
[] = {
7690 /* These are the signal names defined by draft-ietf-secsh-connect-23.
7691 * They include all the ISO C signals, but are a subset of the POSIX
7692 * required signals. */
7693 {"SIGINT (Interrupt)", TS_SIGINT
},
7694 {"SIGTERM (Terminate)", TS_SIGTERM
},
7695 {"SIGKILL (Kill)", TS_SIGKILL
},
7696 {"SIGQUIT (Quit)", TS_SIGQUIT
},
7697 {"SIGHUP (Hangup)", TS_SIGHUP
},
7698 {"More signals", TS_SUBMENU
},
7699 {"SIGABRT", TS_SIGABRT
}, {"SIGALRM", TS_SIGALRM
},
7700 {"SIGFPE", TS_SIGFPE
}, {"SIGILL", TS_SIGILL
},
7701 {"SIGPIPE", TS_SIGPIPE
}, {"SIGSEGV", TS_SIGSEGV
},
7702 {"SIGUSR1", TS_SIGUSR1
}, {"SIGUSR2", TS_SIGUSR2
},
7705 static const struct telnet_special specials_end
[] = {
7708 /* XXX review this length for any changes: */
7709 static struct telnet_special ssh_specials
[lenof(ssh2_transport_specials
) +
7710 lenof(ssh2_session_specials
) +
7711 lenof(specials_end
)];
7712 Ssh ssh
= (Ssh
) handle
;
7714 #define ADD_SPECIALS(name) \
7716 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7717 memcpy(&ssh_specials[i], name, sizeof name); \
7721 if (ssh
->version
== 1) {
7722 /* Don't bother offering IGNORE if we've decided the remote
7723 * won't cope with it, since we wouldn't bother sending it if
7725 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7726 ADD_SPECIALS(ssh1_ignore_special
);
7727 } else if (ssh
->version
== 2) {
7728 ADD_SPECIALS(ssh2_transport_specials
);
7730 ADD_SPECIALS(ssh2_session_specials
);
7731 } /* else we're not ready yet */
7734 ADD_SPECIALS(specials_end
);
7735 return ssh_specials
;
7743 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7744 * can send an EOF and collect resulting output (e.g. `plink
7747 static void ssh_special(void *handle
, Telnet_Special code
)
7749 Ssh ssh
= (Ssh
) handle
;
7750 struct Packet
*pktout
;
7752 if (code
== TS_EOF
) {
7753 if (ssh
->state
!= SSH_STATE_SESSION
) {
7755 * Buffer the EOF in case we are pre-SESSION, so we can
7756 * send it as soon as we reach SESSION.
7759 ssh
->eof_needed
= TRUE
;
7762 if (ssh
->version
== 1) {
7763 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
7764 } else if (ssh
->mainchan
) {
7765 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
7766 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7767 ssh2_pkt_send(ssh
, pktout
);
7769 logevent("Sent EOF message");
7770 } else if (code
== TS_PING
|| code
== TS_NOP
) {
7771 if (ssh
->state
== SSH_STATE_CLOSED
7772 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7773 if (ssh
->version
== 1) {
7774 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7775 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
7777 pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
7778 ssh2_pkt_addstring_start(pktout
);
7779 ssh2_pkt_send_noqueue(ssh
, pktout
);
7781 } else if (code
== TS_REKEY
) {
7782 if (!ssh
->kex_in_progress
&& ssh
->version
== 2) {
7783 do_ssh2_transport(ssh
, "Initiating key re-exchange at"
7784 " user request", -1, NULL
);
7786 } else if (code
== TS_BRK
) {
7787 if (ssh
->state
== SSH_STATE_CLOSED
7788 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7789 if (ssh
->version
== 1) {
7790 logevent("Unable to send BREAK signal in SSH1");
7791 } else if (ssh
->mainchan
) {
7792 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7793 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7794 ssh2_pkt_addstring(pktout
, "break");
7795 ssh2_pkt_addbool(pktout
, 0);
7796 ssh2_pkt_adduint32(pktout
, 0); /* default break length */
7797 ssh2_pkt_send(ssh
, pktout
);
7800 /* Is is a POSIX signal? */
7801 char *signame
= NULL
;
7802 if (code
== TS_SIGABRT
) signame
= "ABRT";
7803 if (code
== TS_SIGALRM
) signame
= "ALRM";
7804 if (code
== TS_SIGFPE
) signame
= "FPE";
7805 if (code
== TS_SIGHUP
) signame
= "HUP";
7806 if (code
== TS_SIGILL
) signame
= "ILL";
7807 if (code
== TS_SIGINT
) signame
= "INT";
7808 if (code
== TS_SIGKILL
) signame
= "KILL";
7809 if (code
== TS_SIGPIPE
) signame
= "PIPE";
7810 if (code
== TS_SIGQUIT
) signame
= "QUIT";
7811 if (code
== TS_SIGSEGV
) signame
= "SEGV";
7812 if (code
== TS_SIGTERM
) signame
= "TERM";
7813 if (code
== TS_SIGUSR1
) signame
= "USR1";
7814 if (code
== TS_SIGUSR2
) signame
= "USR2";
7815 /* The SSH-2 protocol does in principle support arbitrary named
7816 * signals, including signame@domain, but we don't support those. */
7818 /* It's a signal. */
7819 if (ssh
->version
== 2 && ssh
->mainchan
) {
7820 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7821 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7822 ssh2_pkt_addstring(pktout
, "signal");
7823 ssh2_pkt_addbool(pktout
, 0);
7824 ssh2_pkt_addstring(pktout
, signame
);
7825 ssh2_pkt_send(ssh
, pktout
);
7826 logeventf(ssh
, "Sent signal SIG%s", signame
);
7829 /* Never heard of it. Do nothing */
7834 void *new_sock_channel(void *handle
, Socket s
)
7836 Ssh ssh
= (Ssh
) handle
;
7837 struct ssh_channel
*c
;
7838 c
= snew(struct ssh_channel
);
7842 c
->remoteid
= -1; /* to be set when open confirmed */
7843 c
->localid
= alloc_channel_id(ssh
);
7845 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
7847 bufchain_init(&c
->v
.v2
.outbuffer
);
7848 add234(ssh
->channels
, c
);
7854 * This is called when stdout/stderr (the entity to which
7855 * from_backend sends data) manages to clear some backlog.
7857 static void ssh_unthrottle(void *handle
, int bufsize
)
7859 Ssh ssh
= (Ssh
) handle
;
7860 if (ssh
->version
== 1) {
7861 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
7862 ssh
->v1_stdout_throttling
= 0;
7863 ssh1_throttle(ssh
, -1);
7866 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
7867 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
7871 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
7873 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
7875 struct Packet
*pktout
;
7877 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
7879 if (ssh
->version
== 1) {
7880 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
7881 PKT_INT
, c
->localid
,
7884 /* PKT_STR, <org:orgport>, */
7887 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
7888 ssh2_pkt_addstring(pktout
, "direct-tcpip");
7889 ssh2_pkt_adduint32(pktout
, c
->localid
);
7890 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7891 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);/* our window size */
7892 ssh2_pkt_adduint32(pktout
, 0x4000UL
); /* our max pkt size */
7893 ssh2_pkt_addstring(pktout
, hostname
);
7894 ssh2_pkt_adduint32(pktout
, port
);
7896 * We make up values for the originator data; partly it's
7897 * too much hassle to keep track, and partly I'm not
7898 * convinced the server should be told details like that
7899 * about my local network configuration.
7901 ssh2_pkt_addstring(pktout
, "client-side-connection");
7902 ssh2_pkt_adduint32(pktout
, 0);
7903 ssh2_pkt_send(ssh
, pktout
);
7907 static Socket
ssh_socket(void *handle
)
7909 Ssh ssh
= (Ssh
) handle
;
7913 static int ssh_sendok(void *handle
)
7915 Ssh ssh
= (Ssh
) handle
;
7916 return ssh
->send_ok
;
7919 static int ssh_ldisc(void *handle
, int option
)
7921 Ssh ssh
= (Ssh
) handle
;
7922 if (option
== LD_ECHO
)
7923 return ssh
->echoing
;
7924 if (option
== LD_EDIT
)
7925 return ssh
->editing
;
7929 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
7931 Ssh ssh
= (Ssh
) handle
;
7935 static void ssh_provide_logctx(void *handle
, void *logctx
)
7937 Ssh ssh
= (Ssh
) handle
;
7938 ssh
->logctx
= logctx
;
7941 static int ssh_return_exitcode(void *handle
)
7943 Ssh ssh
= (Ssh
) handle
;
7947 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
7951 * cfg_info for SSH is the currently running version of the
7952 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
7954 static int ssh_cfg_info(void *handle
)
7956 Ssh ssh
= (Ssh
) handle
;
7957 return ssh
->version
;
7961 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
7962 * that fails. This variable is the means by which scp.c can reach
7963 * into the SSH code and find out which one it got.
7965 extern int ssh_fallback_cmd(void *handle
)
7967 Ssh ssh
= (Ssh
) handle
;
7968 return ssh
->fallback_cmd
;
7971 Backend ssh_backend
= {
7981 ssh_return_exitcode
,