17 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
18 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
19 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
20 #define SSH1_CMSG_USER 4 /* 0x4 */
21 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
22 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
23 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
24 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
25 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
26 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
27 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
28 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
29 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
30 #define SSH1_SMSG_FAILURE 15 /* 0xf */
31 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
32 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
33 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
34 #define SSH1_CMSG_EOF 19 /* 0x13 */
35 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
36 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
37 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
38 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
39 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
40 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
41 #define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
42 #define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
43 #define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
44 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
45 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
46 #define SSH1_MSG_IGNORE 32 /* 0x20 */
47 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
48 #define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
49 #define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
50 #define SSH1_MSG_DEBUG 36 /* 0x24 */
51 #define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
52 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
53 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
54 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
55 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
56 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
57 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
59 #define SSH1_AUTH_TIS 5 /* 0x5 */
60 #define SSH1_AUTH_CCARD 16 /* 0x10 */
62 #define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
63 /* Mask for protoflags we will echo back to server if seen */
64 #define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
66 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
67 #define SSH2_MSG_IGNORE 2 /* 0x2 */
68 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
69 #define SSH2_MSG_DEBUG 4 /* 0x4 */
70 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
71 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
72 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
73 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
74 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
75 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
76 #define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
77 #define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
78 #define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
79 #define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
80 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
81 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
82 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
83 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
84 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
85 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
86 #define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
87 #define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
88 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
89 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
90 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
91 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
92 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
93 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
94 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
95 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
96 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
97 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
98 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
99 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
100 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
101 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
104 * Packet type contexts, so that ssh2_pkt_type can correctly decode
105 * the ambiguous type numbers back into the correct type strings.
107 #define SSH2_PKTCTX_DHGROUP 0x0001
108 #define SSH2_PKTCTX_DHGEX 0x0002
109 #define SSH2_PKTCTX_KEX_MASK 0x000F
110 #define SSH2_PKTCTX_PUBLICKEY 0x0010
111 #define SSH2_PKTCTX_PASSWORD 0x0020
112 #define SSH2_PKTCTX_KBDINTER 0x0040
113 #define SSH2_PKTCTX_AUTH_MASK 0x00F0
115 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
116 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
117 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
118 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
119 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
120 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
121 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
122 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
123 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
124 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
125 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
126 #define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
127 #define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
128 #define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
129 #define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
131 static const char *const ssh2_disconnect_reasons
[] = {
133 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
134 "SSH_DISCONNECT_PROTOCOL_ERROR",
135 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
136 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
137 "SSH_DISCONNECT_MAC_ERROR",
138 "SSH_DISCONNECT_COMPRESSION_ERROR",
139 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
140 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
141 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
142 "SSH_DISCONNECT_CONNECTION_LOST",
143 "SSH_DISCONNECT_BY_APPLICATION",
144 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
145 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
146 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
147 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
150 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
151 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
152 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
153 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
155 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
158 * Various remote-bug flags.
160 #define BUG_CHOKES_ON_SSH1_IGNORE 1
161 #define BUG_SSH2_HMAC 2
162 #define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
163 #define BUG_CHOKES_ON_RSA 8
164 #define BUG_SSH2_RSA_PADDING 16
165 #define BUG_SSH2_DERIVEKEY 32
166 #define BUG_SSH2_REKEY 64
167 #define BUG_SSH2_PK_SESSIONID 128
169 #define translate(x) if (type == x) return #x
170 #define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
171 static char *ssh1_pkt_type(int type
)
173 translate(SSH1_MSG_DISCONNECT
);
174 translate(SSH1_SMSG_PUBLIC_KEY
);
175 translate(SSH1_CMSG_SESSION_KEY
);
176 translate(SSH1_CMSG_USER
);
177 translate(SSH1_CMSG_AUTH_RSA
);
178 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE
);
179 translate(SSH1_CMSG_AUTH_RSA_RESPONSE
);
180 translate(SSH1_CMSG_AUTH_PASSWORD
);
181 translate(SSH1_CMSG_REQUEST_PTY
);
182 translate(SSH1_CMSG_WINDOW_SIZE
);
183 translate(SSH1_CMSG_EXEC_SHELL
);
184 translate(SSH1_CMSG_EXEC_CMD
);
185 translate(SSH1_SMSG_SUCCESS
);
186 translate(SSH1_SMSG_FAILURE
);
187 translate(SSH1_CMSG_STDIN_DATA
);
188 translate(SSH1_SMSG_STDOUT_DATA
);
189 translate(SSH1_SMSG_STDERR_DATA
);
190 translate(SSH1_CMSG_EOF
);
191 translate(SSH1_SMSG_EXIT_STATUS
);
192 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
);
193 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE
);
194 translate(SSH1_MSG_CHANNEL_DATA
);
195 translate(SSH1_MSG_CHANNEL_CLOSE
);
196 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
);
197 translate(SSH1_SMSG_X11_OPEN
);
198 translate(SSH1_CMSG_PORT_FORWARD_REQUEST
);
199 translate(SSH1_MSG_PORT_OPEN
);
200 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING
);
201 translate(SSH1_SMSG_AGENT_OPEN
);
202 translate(SSH1_MSG_IGNORE
);
203 translate(SSH1_CMSG_EXIT_CONFIRMATION
);
204 translate(SSH1_CMSG_X11_REQUEST_FORWARDING
);
205 translate(SSH1_CMSG_AUTH_RHOSTS_RSA
);
206 translate(SSH1_MSG_DEBUG
);
207 translate(SSH1_CMSG_REQUEST_COMPRESSION
);
208 translate(SSH1_CMSG_AUTH_TIS
);
209 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE
);
210 translate(SSH1_CMSG_AUTH_TIS_RESPONSE
);
211 translate(SSH1_CMSG_AUTH_CCARD
);
212 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE
);
213 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE
);
216 static char *ssh2_pkt_type(int pkt_ctx
, int type
)
218 translate(SSH2_MSG_DISCONNECT
);
219 translate(SSH2_MSG_IGNORE
);
220 translate(SSH2_MSG_UNIMPLEMENTED
);
221 translate(SSH2_MSG_DEBUG
);
222 translate(SSH2_MSG_SERVICE_REQUEST
);
223 translate(SSH2_MSG_SERVICE_ACCEPT
);
224 translate(SSH2_MSG_KEXINIT
);
225 translate(SSH2_MSG_NEWKEYS
);
226 translatec(SSH2_MSG_KEXDH_INIT
, SSH2_PKTCTX_DHGROUP
);
227 translatec(SSH2_MSG_KEXDH_REPLY
, SSH2_PKTCTX_DHGROUP
);
228 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST
, SSH2_PKTCTX_DHGEX
);
229 translatec(SSH2_MSG_KEX_DH_GEX_GROUP
, SSH2_PKTCTX_DHGEX
);
230 translatec(SSH2_MSG_KEX_DH_GEX_INIT
, SSH2_PKTCTX_DHGEX
);
231 translatec(SSH2_MSG_KEX_DH_GEX_REPLY
, SSH2_PKTCTX_DHGEX
);
232 translate(SSH2_MSG_USERAUTH_REQUEST
);
233 translate(SSH2_MSG_USERAUTH_FAILURE
);
234 translate(SSH2_MSG_USERAUTH_SUCCESS
);
235 translate(SSH2_MSG_USERAUTH_BANNER
);
236 translatec(SSH2_MSG_USERAUTH_PK_OK
, SSH2_PKTCTX_PUBLICKEY
);
237 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
, SSH2_PKTCTX_PASSWORD
);
238 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST
, SSH2_PKTCTX_KBDINTER
);
239 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE
, SSH2_PKTCTX_KBDINTER
);
240 translate(SSH2_MSG_GLOBAL_REQUEST
);
241 translate(SSH2_MSG_REQUEST_SUCCESS
);
242 translate(SSH2_MSG_REQUEST_FAILURE
);
243 translate(SSH2_MSG_CHANNEL_OPEN
);
244 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
245 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
246 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
247 translate(SSH2_MSG_CHANNEL_DATA
);
248 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA
);
249 translate(SSH2_MSG_CHANNEL_EOF
);
250 translate(SSH2_MSG_CHANNEL_CLOSE
);
251 translate(SSH2_MSG_CHANNEL_REQUEST
);
252 translate(SSH2_MSG_CHANNEL_SUCCESS
);
253 translate(SSH2_MSG_CHANNEL_FAILURE
);
259 #define GET_32BIT(cp) \
260 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
261 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
262 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
263 ((unsigned long)(unsigned char)(cp)[3]))
265 #define PUT_32BIT(cp, value) { \
266 (cp)[0] = (unsigned char)((value) >> 24); \
267 (cp)[1] = (unsigned char)((value) >> 16); \
268 (cp)[2] = (unsigned char)((value) >> 8); \
269 (cp)[3] = (unsigned char)(value); }
271 /* Enumeration values for fields in SSH-1 packets */
273 PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
,
274 /* These values are for communicating relevant semantics of
275 * fields to the packet logging code. */
276 PKTT_OTHER
, PKTT_PASSWORD
, PKTT_DATA
280 * Coroutine mechanics for the sillier bits of the code. If these
281 * macros look impenetrable to you, you might find it helpful to
284 * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
286 * which explains the theory behind these macros.
288 * In particular, if you are getting `case expression not constant'
289 * errors when building with MS Visual Studio, this is because MS's
290 * Edit and Continue debugging feature causes their compiler to
291 * violate ANSI C. To disable Edit and Continue debugging:
293 * - right-click ssh.c in the FileView
295 * - select the C/C++ tab and the General category
296 * - under `Debug info:', select anything _other_ than `Program
297 * Database for Edit and Continue'.
299 #define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
302 if (!ssh->t) ssh->t = snew(struct t); \
304 #define crFinish(z) } *crLine = 0; return (z); }
305 #define crFinishV } *crLine = 0; return; }
306 #define crReturn(z) \
308 *crLine =__LINE__; return (z); case __LINE__:;\
312 *crLine=__LINE__; return; case __LINE__:;\
314 #define crStop(z) do{ *crLine = 0; return (z); }while(0)
315 #define crStopV do{ *crLine = 0; return; }while(0)
316 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
317 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
319 typedef struct ssh_tag
*Ssh
;
322 static struct Packet
*ssh2_pkt_init(int pkt_type
);
323 static void ssh2_pkt_addbool(struct Packet
*, unsigned char value
);
324 static void ssh2_pkt_adduint32(struct Packet
*, unsigned long value
);
325 static void ssh2_pkt_addstring_start(struct Packet
*);
326 static void ssh2_pkt_addstring_str(struct Packet
*, char *data
);
327 static void ssh2_pkt_addstring_data(struct Packet
*, char *data
, int len
);
328 static void ssh2_pkt_addstring(struct Packet
*, char *data
);
329 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
);
330 static void ssh2_pkt_addmp(struct Packet
*, Bignum b
);
331 static int ssh2_pkt_construct(Ssh
, struct Packet
*);
332 static void ssh2_pkt_send(Ssh
, struct Packet
*);
333 static void ssh2_pkt_send_noqueue(Ssh
, struct Packet
*);
334 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
335 struct Packet
*pktin
);
336 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
337 struct Packet
*pktin
);
340 * Buffer management constants. There are several of these for
341 * various different purposes:
343 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
344 * on a local data stream before we throttle the whole SSH
345 * connection (in SSH1 only). Throttling the whole connection is
346 * pretty drastic so we set this high in the hope it won't
349 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
350 * on the SSH connection itself before we defensively throttle
351 * _all_ local data streams. This is pretty drastic too (though
352 * thankfully unlikely in SSH2 since the window mechanism should
353 * ensure that the server never has any need to throttle its end
354 * of the connection), so we set this high as well.
356 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
360 #define SSH1_BUFFER_LIMIT 32768
361 #define SSH_MAX_BACKLOG 32768
362 #define OUR_V2_WINSIZE 16384
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 int ssh_do_close(Ssh ssh
, int notify_exit
);
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 */
647 tree234
*rportfwds
, *portfwds
;
651 SSH_STATE_BEFORE_SIZE
,
657 int size_needed
, eof_needed
;
659 struct Packet
**queue
;
660 int queuelen
, queuesize
;
662 unsigned char *deferred_send_data
;
663 int deferred_len
, deferred_size
;
666 * Gross hack: pscp will try to start SFTP but fall back to
667 * scp1 if that fails. This variable is the means by which
668 * scp.c can reach into the SSH code and find out which one it
674 * Used for username and password input.
676 char *userpass_input_buffer
;
677 int userpass_input_buflen
;
678 int userpass_input_bufpos
;
679 int userpass_input_echo
;
686 int v1_throttle_count
;
689 int v1_stdout_throttling
;
690 int v2_outgoing_sequence
;
692 int ssh1_rdpkt_crstate
;
693 int ssh2_rdpkt_crstate
;
694 int do_ssh_init_crstate
;
695 int ssh_gotdata_crstate
;
696 int do_ssh1_login_crstate
;
697 int do_ssh1_connection_crstate
;
698 int do_ssh2_transport_crstate
;
699 int do_ssh2_authconn_crstate
;
701 void *do_ssh_init_state
;
702 void *do_ssh1_login_state
;
703 void *do_ssh2_transport_state
;
704 void *do_ssh2_authconn_state
;
706 struct rdpkt1_state_tag rdpkt1_state
;
707 struct rdpkt2_state_tag rdpkt2_state
;
709 /* ssh1 and ssh2 use this for different things, but both use it */
710 int protocol_initial_phase_done
;
712 void (*protocol
) (Ssh ssh
, unsigned char *in
, int inlen
,
714 struct Packet
*(*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
717 * We maintain a full _copy_ of a Config structure here, not
718 * merely a pointer to it. That way, when we're passed a new
719 * one for reconfiguration, we can check the differences and
720 * potentially reconfigure port forwardings etc in mid-session.
725 * Used to transfer data back from async agent callbacks.
727 void *agent_response
;
728 int agent_response_len
;
731 * Dispatch table for packet types that we may have to deal
734 handler_fn_t packet_dispatch
[256];
737 * Queues of one-off handler functions for success/failure
738 * indications from a request.
740 struct queued_handler
*qhead
, *qtail
;
743 * This module deals with sending keepalives.
748 * Track incoming and outgoing data sizes and time, for
751 unsigned long incoming_data_size
, outgoing_data_size
, deferred_data_size
;
752 unsigned long max_data_size
;
754 long next_rekey
, last_rekey
;
755 char *deferred_rekey_reason
; /* points to STATIC string; don't free */
758 #define logevent(s) logevent(ssh->frontend, s)
760 /* logevent, only printf-formatted. */
761 static void logeventf(Ssh ssh
, const char *fmt
, ...)
767 buf
= dupvprintf(fmt
, ap
);
773 #define bombout(msg) \
775 char *text = dupprintf msg; \
776 ssh_do_close(ssh, FALSE); \
778 connection_fatal(ssh->frontend, "%s", text); \
782 /* Functions to leave bits out of the SSH packet log file. */
784 static void dont_log_password(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
786 if (ssh
->cfg
.logomitpass
)
787 pkt
->logmode
= blanktype
;
790 static void dont_log_data(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
792 if (ssh
->cfg
.logomitdata
)
793 pkt
->logmode
= blanktype
;
796 static void end_log_omission(Ssh ssh
, struct Packet
*pkt
)
798 pkt
->logmode
= PKTLOG_EMIT
;
801 static int ssh_channelcmp(void *av
, void *bv
)
803 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
804 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
805 if (a
->localid
< b
->localid
)
807 if (a
->localid
> b
->localid
)
811 static int ssh_channelfind(void *av
, void *bv
)
813 unsigned *a
= (unsigned *) av
;
814 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
822 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
824 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
825 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
827 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
828 return i
< 0 ?
-1 : +1;
829 if (a
->dport
> b
->dport
)
831 if (a
->dport
< b
->dport
)
836 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
838 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
839 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
841 if (a
->sport
> b
->sport
)
843 if (a
->sport
< b
->sport
)
849 * Special form of strcmp which can cope with NULL inputs. NULL is
850 * defined to sort before even the empty string.
852 static int nullstrcmp(const char *a
, const char *b
)
854 if (a
== NULL
&& b
== NULL
)
863 static int ssh_portcmp(void *av
, void *bv
)
865 struct ssh_portfwd
*a
= (struct ssh_portfwd
*) av
;
866 struct ssh_portfwd
*b
= (struct ssh_portfwd
*) bv
;
868 if (a
->type
> b
->type
)
870 if (a
->type
< b
->type
)
872 if (a
->addressfamily
> b
->addressfamily
)
874 if (a
->addressfamily
< b
->addressfamily
)
876 if ( (i
= nullstrcmp(a
->saddr
, b
->saddr
)) != 0)
877 return i
< 0 ?
-1 : +1;
878 if (a
->sport
> b
->sport
)
880 if (a
->sport
< b
->sport
)
882 if (a
->type
!= 'D') {
883 if ( (i
= nullstrcmp(a
->daddr
, b
->daddr
)) != 0)
884 return i
< 0 ?
-1 : +1;
885 if (a
->dport
> b
->dport
)
887 if (a
->dport
< b
->dport
)
893 static int alloc_channel_id(Ssh ssh
)
895 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
896 unsigned low
, high
, mid
;
898 struct ssh_channel
*c
;
901 * First-fit allocation of channel numbers: always pick the
902 * lowest unused one. To do this, binary-search using the
903 * counted B-tree to find the largest channel ID which is in a
904 * contiguous sequence from the beginning. (Precisely
905 * everything in that sequence must have ID equal to its tree
906 * index plus CHANNEL_NUMBER_OFFSET.)
908 tsize
= count234(ssh
->channels
);
912 while (high
- low
> 1) {
913 mid
= (high
+ low
) / 2;
914 c
= index234(ssh
->channels
, mid
);
915 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
916 low
= mid
; /* this one is fine */
918 high
= mid
; /* this one is past it */
921 * Now low points to either -1, or the tree index of the
922 * largest ID in the initial sequence.
925 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
926 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
928 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
931 static void c_write(Ssh ssh
, const char *buf
, int len
)
933 if ((flags
& FLAG_STDERR
)) {
935 for (i
= 0; i
< len
; i
++)
937 fputc(buf
[i
], stderr
);
940 from_backend(ssh
->frontend
, 1, buf
, len
);
943 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
946 for (i
= 0; i
< len
; i
++) {
948 c_write(ssh
, "\r\n", 2);
949 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
950 c_write(ssh
, buf
+ i
, 1);
954 static void c_write_str(Ssh ssh
, const char *buf
)
956 c_write(ssh
, buf
, strlen(buf
));
959 static void ssh_free_packet(struct Packet
*pkt
)
964 static struct Packet
*ssh_new_packet(void)
966 struct Packet
*pkt
= snew(struct Packet
);
970 pkt
->logmode
= PKTLOG_EMIT
;
978 * Collect incoming data in the incoming packet buffer.
979 * Decipher and verify the packet when it is completely read.
980 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
981 * Update the *data and *datalen variables.
982 * Return a Packet structure when a packet is completed.
984 static struct Packet
*ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
986 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
988 crBegin(ssh
->ssh1_rdpkt_crstate
);
990 st
->pktin
= ssh_new_packet();
993 st
->pktin
->length
= 0;
995 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
996 while ((*datalen
) == 0)
998 st
->len
= (st
->len
<< 8) + **data
;
999 (*data
)++, (*datalen
)--;
1002 st
->pad
= 8 - (st
->len
% 8);
1003 st
->biglen
= st
->len
+ st
->pad
;
1004 st
->pktin
->length
= st
->len
- 5;
1006 if (st
->biglen
< 0) {
1007 bombout(("Extremely large packet length from server suggests"
1008 " data stream corruption"));
1009 ssh_free_packet(st
->pktin
);
1013 st
->pktin
->maxlen
= st
->biglen
;
1014 st
->pktin
->data
= snewn(st
->biglen
+ APIEXTRA
, unsigned char);
1016 st
->to_read
= st
->biglen
;
1017 st
->p
= st
->pktin
->data
;
1018 while (st
->to_read
> 0) {
1019 st
->chunk
= st
->to_read
;
1020 while ((*datalen
) == 0)
1022 if (st
->chunk
> (*datalen
))
1023 st
->chunk
= (*datalen
);
1024 memcpy(st
->p
, *data
, st
->chunk
);
1026 *datalen
-= st
->chunk
;
1028 st
->to_read
-= st
->chunk
;
1031 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, st
->pktin
->data
,
1032 st
->biglen
, NULL
)) {
1033 bombout(("Network attack (CRC compensation) detected!"));
1034 ssh_free_packet(st
->pktin
);
1039 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, st
->pktin
->data
, st
->biglen
);
1041 st
->realcrc
= crc32_compute(st
->pktin
->data
, st
->biglen
- 4);
1042 st
->gotcrc
= GET_32BIT(st
->pktin
->data
+ st
->biglen
- 4);
1043 if (st
->gotcrc
!= st
->realcrc
) {
1044 bombout(("Incorrect CRC received on packet"));
1045 ssh_free_packet(st
->pktin
);
1049 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1050 st
->pktin
->savedpos
= 0;
1052 if (ssh
->v1_compressing
) {
1053 unsigned char *decompblk
;
1055 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
1056 st
->pktin
->body
- 1, st
->pktin
->length
+ 1,
1057 &decompblk
, &decomplen
)) {
1058 bombout(("Zlib decompression encountered invalid data"));
1059 ssh_free_packet(st
->pktin
);
1063 if (st
->pktin
->maxlen
< st
->pad
+ decomplen
) {
1064 st
->pktin
->maxlen
= st
->pad
+ decomplen
;
1065 st
->pktin
->data
= sresize(st
->pktin
->data
,
1066 st
->pktin
->maxlen
+ APIEXTRA
,
1068 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1071 memcpy(st
->pktin
->body
- 1, decompblk
, decomplen
);
1073 st
->pktin
->length
= decomplen
- 1;
1076 st
->pktin
->type
= st
->pktin
->body
[-1];
1079 * Log incoming packet, possibly omitting sensitive fields.
1083 struct logblank_t blank
;
1084 if (ssh
->cfg
.logomitdata
) {
1085 int do_blank
= FALSE
, blank_prefix
= 0;
1086 /* "Session data" packets - omit the data field */
1087 if ((st
->pktin
->type
== SSH1_SMSG_STDOUT_DATA
) ||
1088 (st
->pktin
->type
== SSH1_SMSG_STDERR_DATA
)) {
1089 do_blank
= TRUE
; blank_prefix
= 0;
1090 } else if (st
->pktin
->type
== SSH1_MSG_CHANNEL_DATA
) {
1091 do_blank
= TRUE
; blank_prefix
= 4;
1094 blank
.offset
= blank_prefix
;
1095 blank
.len
= st
->pktin
->length
;
1096 blank
.type
= PKTLOG_OMIT
;
1100 log_packet(ssh
->logctx
,
1101 PKT_INCOMING
, st
->pktin
->type
,
1102 ssh1_pkt_type(st
->pktin
->type
),
1103 st
->pktin
->body
, st
->pktin
->length
,
1107 crFinish(st
->pktin
);
1110 static struct Packet
*ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1112 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1114 crBegin(ssh
->ssh2_rdpkt_crstate
);
1116 st
->pktin
= ssh_new_packet();
1118 st
->pktin
->type
= 0;
1119 st
->pktin
->length
= 0;
1121 st
->cipherblk
= ssh
->sccipher
->blksize
;
1124 if (st
->cipherblk
< 8)
1127 st
->pktin
->data
= snewn(st
->cipherblk
+ APIEXTRA
, unsigned char);
1130 * Acquire and decrypt the first block of the packet. This will
1131 * contain the length and padding details.
1133 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1134 while ((*datalen
) == 0)
1136 st
->pktin
->data
[st
->i
] = *(*data
)++;
1141 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1142 st
->pktin
->data
, st
->cipherblk
);
1145 * Now get the length and padding figures.
1147 st
->len
= GET_32BIT(st
->pktin
->data
);
1148 st
->pad
= st
->pktin
->data
[4];
1151 * _Completely_ silly lengths should be stomped on before they
1152 * do us any more damage.
1154 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
1155 bombout(("Incoming packet was garbled on decryption"));
1156 ssh_free_packet(st
->pktin
);
1161 * This enables us to deduce the payload length.
1163 st
->payload
= st
->len
- st
->pad
- 1;
1165 st
->pktin
->length
= st
->payload
+ 5;
1168 * So now we can work out the total packet length.
1170 st
->packetlen
= st
->len
+ 4;
1171 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1174 * Allocate memory for the rest of the packet.
1176 st
->pktin
->maxlen
= st
->packetlen
+ st
->maclen
;
1177 st
->pktin
->data
= sresize(st
->pktin
->data
,
1178 st
->pktin
->maxlen
+ APIEXTRA
,
1182 * Read and decrypt the remainder of the packet.
1184 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1186 while ((*datalen
) == 0)
1188 st
->pktin
->data
[st
->i
] = *(*data
)++;
1191 /* Decrypt everything _except_ the MAC. */
1193 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1194 st
->pktin
->data
+ st
->cipherblk
,
1195 st
->packetlen
- st
->cipherblk
);
1197 st
->pktin
->encrypted_len
= st
->packetlen
;
1203 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, st
->pktin
->data
, st
->len
+ 4,
1204 st
->incoming_sequence
)) {
1205 bombout(("Incorrect MAC received on packet"));
1206 ssh_free_packet(st
->pktin
);
1210 st
->pktin
->sequence
= st
->incoming_sequence
++;
1213 * Decompress packet payload.
1216 unsigned char *newpayload
;
1219 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1220 st
->pktin
->data
+ 5, st
->pktin
->length
- 5,
1221 &newpayload
, &newlen
)) {
1222 if (st
->pktin
->maxlen
< newlen
+ 5) {
1223 st
->pktin
->maxlen
= newlen
+ 5;
1224 st
->pktin
->data
= sresize(st
->pktin
->data
,
1225 st
->pktin
->maxlen
+ APIEXTRA
,
1228 st
->pktin
->length
= 5 + newlen
;
1229 memcpy(st
->pktin
->data
+ 5, newpayload
, newlen
);
1234 st
->pktin
->savedpos
= 6;
1235 st
->pktin
->body
= st
->pktin
->data
;
1236 st
->pktin
->type
= st
->pktin
->data
[5];
1239 * Log incoming packet, possibly omitting sensitive fields.
1243 struct logblank_t blank
;
1244 if (ssh
->cfg
.logomitdata
) {
1245 int do_blank
= FALSE
, blank_prefix
= 0;
1246 /* "Session data" packets - omit the data field */
1247 if (st
->pktin
->type
== SSH2_MSG_CHANNEL_DATA
) {
1248 do_blank
= TRUE
; blank_prefix
= 4;
1249 } else if (st
->pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1250 do_blank
= TRUE
; blank_prefix
= 8;
1253 blank
.offset
= blank_prefix
;
1254 blank
.len
= (st
->pktin
->length
-6) - blank_prefix
;
1255 blank
.type
= PKTLOG_OMIT
;
1259 log_packet(ssh
->logctx
, PKT_INCOMING
, st
->pktin
->type
,
1260 ssh2_pkt_type(ssh
->pkt_ctx
, st
->pktin
->type
),
1261 st
->pktin
->data
+6, st
->pktin
->length
-6,
1265 crFinish(st
->pktin
);
1268 static void ssh1_pktout_size(struct Packet
*pkt
, int len
)
1272 len
+= 5; /* type and CRC */
1273 pad
= 8 - (len
% 8);
1276 pkt
->length
= len
- 5;
1277 if (pkt
->maxlen
< biglen
) {
1278 pkt
->maxlen
= biglen
;
1279 pkt
->data
= sresize(pkt
->data
, biglen
+ 4 + APIEXTRA
, unsigned char);
1281 pkt
->body
= pkt
->data
+ 4 + pad
+ 1;
1284 static struct Packet
*s_wrpkt_start(int type
, int len
)
1286 struct Packet
*pkt
= ssh_new_packet();
1287 ssh1_pktout_size(pkt
, len
);
1289 /* Initialise log omission state */
1295 static int s_wrpkt_prepare(Ssh ssh
, struct Packet
*pkt
)
1301 * XXX various versions of SC (including 8.8.4) screw up the
1302 * register allocation in this function and use the same register
1303 * (D6) for len and as a temporary, with predictable results. The
1304 * following sledgehammer prevents this.
1310 pkt
->body
[-1] = pkt
->type
;
1313 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->type
,
1314 ssh1_pkt_type(pkt
->type
),
1315 pkt
->body
, pkt
->length
,
1316 pkt
->nblanks
, pkt
->blanks
);
1317 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1320 if (ssh
->v1_compressing
) {
1321 unsigned char *compblk
;
1323 zlib_compress_block(ssh
->cs_comp_ctx
,
1324 pkt
->body
- 1, pkt
->length
+ 1,
1325 &compblk
, &complen
);
1326 ssh1_pktout_size(pkt
, complen
- 1);
1327 memcpy(pkt
->body
- 1, compblk
, complen
);
1331 len
= pkt
->length
+ 5; /* type and CRC */
1332 pad
= 8 - (len
% 8);
1335 for (i
= 0; i
< pad
; i
++)
1336 pkt
->data
[i
+ 4] = random_byte();
1337 crc
= crc32_compute(pkt
->data
+ 4, biglen
- 4);
1338 PUT_32BIT(pkt
->data
+ biglen
, crc
);
1339 PUT_32BIT(pkt
->data
, len
);
1342 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, pkt
->data
+ 4, biglen
);
1347 static void s_wrpkt(Ssh ssh
, struct Packet
*pkt
)
1350 len
= s_wrpkt_prepare(ssh
, pkt
);
1351 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1352 if (backlog
> SSH_MAX_BACKLOG
)
1353 ssh_throttle_all(ssh
, 1, backlog
);
1356 static void s_wrpkt_defer(Ssh ssh
, struct Packet
*pkt
)
1359 len
= s_wrpkt_prepare(ssh
, pkt
);
1360 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1361 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1362 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1366 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1367 ssh
->deferred_len
+= len
;
1371 * Construct a packet with the specified contents.
1373 static struct Packet
*construct_packet(Ssh ssh
, int pkttype
,
1374 va_list ap1
, va_list ap2
)
1376 unsigned char *p
, *argp
, argchar
;
1377 unsigned long argint
;
1378 int pktlen
, argtype
, arglen
;
1383 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1386 (void) va_arg(ap1
, int);
1390 (void) va_arg(ap1
, int);
1394 (void) va_arg(ap1
, unsigned char *);
1395 arglen
= va_arg(ap1
, int);
1399 argp
= va_arg(ap1
, unsigned char *);
1400 arglen
= strlen((char *)argp
);
1401 pktlen
+= 4 + arglen
;
1404 bn
= va_arg(ap1
, Bignum
);
1405 pktlen
+= ssh1_bignum_length(bn
);
1410 /* ignore this pass */
1417 pkt
= s_wrpkt_start(pkttype
, pktlen
);
1420 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1421 int offset
= p
- pkt
->body
, len
= 0;
1423 /* Actual fields in the packet */
1425 argint
= va_arg(ap2
, int);
1426 PUT_32BIT(p
, argint
);
1430 argchar
= (unsigned char) va_arg(ap2
, int);
1435 argp
= va_arg(ap2
, unsigned char *);
1436 arglen
= va_arg(ap2
, int);
1437 memcpy(p
, argp
, arglen
);
1441 argp
= va_arg(ap2
, unsigned char *);
1442 arglen
= strlen((char *)argp
);
1443 PUT_32BIT(p
, arglen
);
1444 memcpy(p
+ 4, argp
, arglen
);
1448 bn
= va_arg(ap2
, Bignum
);
1449 len
= ssh1_write_bignum(p
, bn
);
1451 /* Tokens for modifications to packet logging */
1453 dont_log_password(ssh
, pkt
, PKTLOG_BLANK
);
1456 dont_log_data(ssh
, pkt
, PKTLOG_OMIT
);
1459 end_log_omission(ssh
, pkt
);
1463 /* Deal with logfile omission, if required. */
1464 if (len
&& (pkt
->logmode
!= PKTLOG_EMIT
)) {
1466 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
,
1468 pkt
->blanks
[pkt
->nblanks
-1].offset
= offset
;
1469 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1470 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1477 static void send_packet(Ssh ssh
, int pkttype
, ...)
1481 va_start(ap1
, pkttype
);
1482 va_start(ap2
, pkttype
);
1483 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1487 ssh_free_packet(pkt
);
1490 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1494 va_start(ap1
, pkttype
);
1495 va_start(ap2
, pkttype
);
1496 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1499 s_wrpkt_defer(ssh
, pkt
);
1500 ssh_free_packet(pkt
);
1503 static int ssh_versioncmp(char *a
, char *b
)
1506 unsigned long av
, bv
;
1508 av
= strtoul(a
, &ae
, 10);
1509 bv
= strtoul(b
, &be
, 10);
1511 return (av
< bv ?
-1 : +1);
1516 av
= strtoul(ae
, &ae
, 10);
1517 bv
= strtoul(be
, &be
, 10);
1519 return (av
< bv ?
-1 : +1);
1524 * Utility routines for putting an SSH-protocol `string' and
1525 * `uint32' into a SHA state.
1528 static void sha_string(SHA_State
* s
, void *str
, int len
)
1530 unsigned char lenblk
[4];
1531 PUT_32BIT(lenblk
, len
);
1532 SHA_Bytes(s
, lenblk
, 4);
1533 SHA_Bytes(s
, str
, len
);
1536 static void sha_uint32(SHA_State
* s
, unsigned i
)
1538 unsigned char intblk
[4];
1539 PUT_32BIT(intblk
, i
);
1540 SHA_Bytes(s
, intblk
, 4);
1544 * SSH2 packet construction functions.
1546 static void ssh2_pkt_ensure(struct Packet
*pkt
, int length
)
1548 if (pkt
->maxlen
< length
) {
1549 pkt
->maxlen
= length
+ 256;
1550 pkt
->data
= sresize(pkt
->data
, pkt
->maxlen
+ APIEXTRA
, unsigned char);
1553 static void ssh2_pkt_adddata(struct Packet
*pkt
, void *data
, int len
)
1555 if (pkt
->logmode
!= PKTLOG_EMIT
) {
1557 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
, struct logblank_t
);
1558 pkt
->blanks
[pkt
->nblanks
-1].offset
= pkt
->length
- 6;
1559 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1560 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1563 ssh2_pkt_ensure(pkt
, pkt
->length
);
1564 memcpy(pkt
->data
+ pkt
->length
- len
, data
, len
);
1566 static void ssh2_pkt_addbyte(struct Packet
*pkt
, unsigned char byte
)
1568 ssh2_pkt_adddata(pkt
, &byte
, 1);
1570 static struct Packet
*ssh2_pkt_init(int pkt_type
)
1572 struct Packet
*pkt
= ssh_new_packet();
1574 ssh2_pkt_addbyte(pkt
, (unsigned char) pkt_type
);
1577 static void ssh2_pkt_addbool(struct Packet
*pkt
, unsigned char value
)
1579 ssh2_pkt_adddata(pkt
, &value
, 1);
1581 static void ssh2_pkt_adduint32(struct Packet
*pkt
, unsigned long value
)
1584 PUT_32BIT(x
, value
);
1585 ssh2_pkt_adddata(pkt
, x
, 4);
1587 static void ssh2_pkt_addstring_start(struct Packet
*pkt
)
1589 ssh2_pkt_adduint32(pkt
, 0);
1590 pkt
->savedpos
= pkt
->length
;
1592 static void ssh2_pkt_addstring_str(struct Packet
*pkt
, char *data
)
1594 ssh2_pkt_adddata(pkt
, data
, strlen(data
));
1595 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1597 static void ssh2_pkt_addstring_data(struct Packet
*pkt
, char *data
, int len
)
1599 ssh2_pkt_adddata(pkt
, data
, len
);
1600 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1602 static void ssh2_pkt_addstring(struct Packet
*pkt
, char *data
)
1604 ssh2_pkt_addstring_start(pkt
);
1605 ssh2_pkt_addstring_str(pkt
, data
);
1607 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1610 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1611 p
= snewn(n
+ 1, unsigned char);
1613 fatalbox("out of memory");
1615 for (i
= 1; i
<= n
; i
++)
1616 p
[i
] = bignum_byte(b
, n
- i
);
1618 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1620 memmove(p
, p
+ i
, n
+ 1 - i
);
1624 static void ssh2_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1628 p
= ssh2_mpint_fmt(b
, &len
);
1629 ssh2_pkt_addstring_start(pkt
);
1630 ssh2_pkt_addstring_data(pkt
, (char *)p
, len
);
1635 * Construct an SSH2 final-form packet: compress it, encrypt it,
1636 * put the MAC on it. Final packet, ready to be sent, is stored in
1637 * pkt->data. Total length is returned.
1639 static int ssh2_pkt_construct(Ssh ssh
, struct Packet
*pkt
)
1641 int cipherblk
, maclen
, padding
, i
;
1644 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[5],
1645 ssh2_pkt_type(ssh
->pkt_ctx
, pkt
->data
[5]),
1646 pkt
->data
+ 6, pkt
->length
- 6,
1647 pkt
->nblanks
, pkt
->blanks
);
1648 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1652 * Compress packet payload.
1655 unsigned char *newpayload
;
1658 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, pkt
->data
+ 5,
1660 &newpayload
, &newlen
)) {
1662 ssh2_pkt_adddata(pkt
, newpayload
, newlen
);
1668 * Add padding. At least four bytes, and must also bring total
1669 * length (minus MAC) up to a multiple of the block size.
1671 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1672 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1675 (cipherblk
- (pkt
->length
+ padding
) % cipherblk
) % cipherblk
;
1676 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1677 ssh2_pkt_ensure(pkt
, pkt
->length
+ padding
+ maclen
);
1678 pkt
->data
[4] = padding
;
1679 for (i
= 0; i
< padding
; i
++)
1680 pkt
->data
[pkt
->length
+ i
] = random_byte();
1681 PUT_32BIT(pkt
->data
, pkt
->length
+ padding
- 4);
1683 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, pkt
->data
,
1684 pkt
->length
+ padding
,
1685 ssh
->v2_outgoing_sequence
);
1686 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1689 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1690 pkt
->data
, pkt
->length
+ padding
);
1692 pkt
->encrypted_len
= pkt
->length
+ padding
;
1694 /* Ready-to-send packet starts at pkt->data. We return length. */
1695 return pkt
->length
+ padding
+ maclen
;
1699 * Routines called from the main SSH code to send packets. There
1700 * are quite a few of these, because we have two separate
1701 * mechanisms for delaying the sending of packets:
1703 * - In order to send an IGNORE message and a password message in
1704 * a single fixed-length blob, we require the ability to
1705 * concatenate the encrypted forms of those two packets _into_ a
1706 * single blob and then pass it to our <network.h> transport
1707 * layer in one go. Hence, there's a deferment mechanism which
1708 * works after packet encryption.
1710 * - In order to avoid sending any connection-layer messages
1711 * during repeat key exchange, we have to queue up any such
1712 * outgoing messages _before_ they are encrypted (and in
1713 * particular before they're allocated sequence numbers), and
1714 * then send them once we've finished.
1716 * I call these mechanisms `defer' and `queue' respectively, so as
1717 * to distinguish them reasonably easily.
1719 * The functions send_noqueue() and defer_noqueue() free the packet
1720 * structure they are passed. Every outgoing packet goes through
1721 * precisely one of these functions in its life; packets passed to
1722 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1723 * these or get queued, and then when the queue is later emptied
1724 * the packets are all passed to defer_noqueue().
1728 * Send an SSH2 packet immediately, without queuing or deferring.
1730 static void ssh2_pkt_send_noqueue(Ssh ssh
, struct Packet
*pkt
)
1734 len
= ssh2_pkt_construct(ssh
, pkt
);
1735 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1736 if (backlog
> SSH_MAX_BACKLOG
)
1737 ssh_throttle_all(ssh
, 1, backlog
);
1739 ssh
->outgoing_data_size
+= pkt
->encrypted_len
;
1740 if (!ssh
->kex_in_progress
&&
1741 ssh
->max_data_size
!= 0 &&
1742 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1743 do_ssh2_transport(ssh
, "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
, "too much data sent", -1, NULL
);
1834 ssh
->deferred_data_size
= 0;
1838 * Send all queued SSH2 packets. We send them by means of
1839 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1840 * packets that needed to be lumped together.
1842 static void ssh2_pkt_queuesend(Ssh ssh
)
1846 assert(!ssh
->queueing
);
1848 for (i
= 0; i
< ssh
->queuelen
; i
++)
1849 ssh2_pkt_defer_noqueue(ssh
, ssh
->queue
[i
]);
1852 ssh_pkt_defersend(ssh
);
1856 void bndebug(char *string
, Bignum b
)
1860 p
= ssh2_mpint_fmt(b
, &len
);
1861 debug(("%s", string
));
1862 for (i
= 0; i
< len
; i
++)
1863 debug((" %02x", p
[i
]));
1869 static void sha_mpint(SHA_State
* s
, Bignum b
)
1873 p
= ssh2_mpint_fmt(b
, &len
);
1874 sha_string(s
, p
, len
);
1879 * Packet decode functions for both SSH1 and SSH2.
1881 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
)
1883 unsigned long value
;
1884 if (pkt
->length
- pkt
->savedpos
< 4)
1885 return 0; /* arrgh, no way to decline (FIXME?) */
1886 value
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1890 static int ssh2_pkt_getbool(struct Packet
*pkt
)
1892 unsigned long value
;
1893 if (pkt
->length
- pkt
->savedpos
< 1)
1894 return 0; /* arrgh, no way to decline (FIXME?) */
1895 value
= pkt
->body
[pkt
->savedpos
] != 0;
1899 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
)
1904 if (pkt
->length
- pkt
->savedpos
< 4)
1906 len
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1911 if (pkt
->length
- pkt
->savedpos
< *length
)
1913 *p
= (char *)(pkt
->body
+ pkt
->savedpos
);
1914 pkt
->savedpos
+= *length
;
1916 static void *ssh_pkt_getdata(struct Packet
*pkt
, int length
)
1918 if (pkt
->length
- pkt
->savedpos
< length
)
1920 pkt
->savedpos
+= length
;
1921 return pkt
->body
+ (pkt
->savedpos
- length
);
1923 static int ssh1_pkt_getrsakey(struct Packet
*pkt
, struct RSAKey
*key
,
1924 unsigned char **keystr
)
1928 j
= makekey(pkt
->body
+ pkt
->savedpos
,
1929 pkt
->length
- pkt
->savedpos
,
1936 assert(pkt
->savedpos
< pkt
->length
);
1940 static Bignum
ssh1_pkt_getmp(struct Packet
*pkt
)
1945 j
= ssh1_read_bignum(pkt
->body
+ pkt
->savedpos
,
1946 pkt
->length
- pkt
->savedpos
, &b
);
1954 static Bignum
ssh2_pkt_getmp(struct Packet
*pkt
)
1960 ssh_pkt_getstring(pkt
, &p
, &length
);
1965 b
= bignum_from_bytes((unsigned char *)p
, length
);
1970 * Helper function to add an SSH2 signature blob to a packet.
1971 * Expects to be shown the public key blob as well as the signature
1972 * blob. Normally works just like ssh2_pkt_addstring, but will
1973 * fiddle with the signature packet if necessary for
1974 * BUG_SSH2_RSA_PADDING.
1976 static void ssh2_add_sigblob(Ssh ssh
, struct Packet
*pkt
,
1977 void *pkblob_v
, int pkblob_len
,
1978 void *sigblob_v
, int sigblob_len
)
1980 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1981 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1983 /* dmemdump(pkblob, pkblob_len); */
1984 /* dmemdump(sigblob, sigblob_len); */
1987 * See if this is in fact an ssh-rsa signature and a buggy
1988 * server; otherwise we can just do this the easy way.
1990 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1991 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1992 int pos
, len
, siglen
;
1995 * Find the byte length of the modulus.
1998 pos
= 4+7; /* skip over "ssh-rsa" */
1999 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
2000 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
2001 pos
+= 4; /* find modulus itself */
2002 while (len
> 0 && pkblob
[pos
] == 0)
2004 /* debug(("modulus length is %d\n", len)); */
2007 * Now find the signature integer.
2009 pos
= 4+7; /* skip over "ssh-rsa" */
2010 siglen
= GET_32BIT(sigblob
+pos
);
2011 /* debug(("signature length is %d\n", siglen)); */
2013 if (len
!= siglen
) {
2014 unsigned char newlen
[4];
2015 ssh2_pkt_addstring_start(pkt
);
2016 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, pos
);
2017 /* dmemdump(sigblob, pos); */
2018 pos
+= 4; /* point to start of actual sig */
2019 PUT_32BIT(newlen
, len
);
2020 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 4);
2021 /* dmemdump(newlen, 4); */
2023 while (len
-- > siglen
) {
2024 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 1);
2025 /* dmemdump(newlen, 1); */
2027 ssh2_pkt_addstring_data(pkt
, (char *)(sigblob
+pos
), siglen
);
2028 /* dmemdump(sigblob+pos, siglen); */
2032 /* Otherwise fall through and do it the easy way. */
2035 ssh2_pkt_addstring_start(pkt
);
2036 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, sigblob_len
);
2040 * Examine the remote side's version string and compare it against
2041 * a list of known buggy implementations.
2043 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
2045 char *imp
; /* pointer to implementation part */
2047 imp
+= strcspn(imp
, "-");
2049 imp
+= strcspn(imp
, "-");
2052 ssh
->remote_bugs
= 0;
2054 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
2055 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
2056 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
2057 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
2058 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
2059 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
2061 * These versions don't support SSH1_MSG_IGNORE, so we have
2062 * to use a different defence against password length
2065 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
2066 logevent("We believe remote version has SSH1 ignore bug");
2069 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
2070 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
2071 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
2073 * These versions need a plain password sent; they can't
2074 * handle having a null and a random length of data after
2077 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
2078 logevent("We believe remote version needs a plain SSH1 password");
2081 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
2082 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
2083 (!strcmp(imp
, "Cisco-1.25")))) {
2085 * These versions apparently have no clue whatever about
2086 * RSA authentication and will panic and die if they see
2087 * an AUTH_RSA message.
2089 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
2090 logevent("We believe remote version can't handle RSA authentication");
2093 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
2094 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
2095 !wc_match("* VShell", imp
) &&
2096 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
2097 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
2098 wc_match("2.1 *", imp
)))) {
2100 * These versions have the HMAC bug.
2102 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
2103 logevent("We believe remote version has SSH2 HMAC bug");
2106 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2107 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2108 !wc_match("* VShell", imp
) &&
2109 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2111 * These versions have the key-derivation bug (failing to
2112 * include the literal shared secret in the hashes that
2113 * generate the keys).
2115 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2116 logevent("We believe remote version has SSH2 key-derivation bug");
2119 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2120 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2121 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2122 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2124 * These versions have the SSH2 RSA padding bug.
2126 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2127 logevent("We believe remote version has SSH2 RSA padding bug");
2130 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2131 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2132 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2134 * These versions have the SSH2 session-ID bug in
2135 * public-key authentication.
2137 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2138 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2141 if (ssh
->cfg
.sshbug_rekey2
== FORCE_ON
||
2142 (ssh
->cfg
.sshbug_rekey2
== AUTO
&&
2143 (wc_match("OpenSSH_2.[0-4]*", imp
) ||
2144 wc_match("OpenSSH_2.5.[0-3]*", imp
) ||
2145 wc_match("Sun_SSH_1.0", imp
) ||
2146 wc_match("Sun_SSH_1.0.1", imp
)))) {
2148 * These versions have the SSH2 rekey bug.
2150 ssh
->remote_bugs
|= BUG_SSH2_REKEY
;
2151 logevent("We believe remote version has SSH2 rekey bug");
2156 * The `software version' part of an SSH version string is required
2157 * to contain no spaces or minus signs.
2159 static void ssh_fix_verstring(char *str
)
2161 /* Eat "SSH-<protoversion>-". */
2162 assert(*str
== 'S'); str
++;
2163 assert(*str
== 'S'); str
++;
2164 assert(*str
== 'H'); str
++;
2165 assert(*str
== '-'); str
++;
2166 while (*str
&& *str
!= '-') str
++;
2167 assert(*str
== '-'); str
++;
2169 /* Convert minus signs and spaces in the remaining string into
2172 if (*str
== '-' || *str
== ' ')
2178 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2180 struct do_ssh_init_state
{
2188 crState(do_ssh_init_state
);
2190 crBegin(ssh
->do_ssh_init_crstate
);
2192 /* Search for the string "SSH-" in the input. */
2195 static const int transS
[] = { 1, 2, 2, 1 };
2196 static const int transH
[] = { 0, 0, 3, 0 };
2197 static const int transminus
[] = { 0, 0, 0, -1 };
2199 s
->i
= transS
[s
->i
];
2201 s
->i
= transH
[s
->i
];
2203 s
->i
= transminus
[s
->i
];
2208 crReturn(1); /* get another character */
2212 s
->vstring
= snewn(s
->vstrsize
, char);
2213 strcpy(s
->vstring
, "SSH-");
2217 crReturn(1); /* get another char */
2218 if (s
->vslen
>= s
->vstrsize
- 1) {
2220 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2222 s
->vstring
[s
->vslen
++] = c
;
2225 s
->version
[s
->i
] = '\0';
2227 } else if (s
->i
< sizeof(s
->version
) - 1)
2228 s
->version
[s
->i
++] = c
;
2229 } else if (c
== '\012')
2233 ssh
->agentfwd_enabled
= FALSE
;
2234 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2236 s
->vstring
[s
->vslen
] = 0;
2237 s
->vstring
[strcspn(s
->vstring
, "\015\012")] = '\0';/* remove EOL chars */
2240 vlog
= snewn(20 + s
->vslen
, char);
2241 sprintf(vlog
, "Server version: %s", s
->vstring
);
2245 ssh_detect_bugs(ssh
, s
->vstring
);
2248 * Decide which SSH protocol version to support.
2251 /* Anything strictly below "2.0" means protocol 1 is supported. */
2252 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2253 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2254 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2256 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2257 bombout(("SSH protocol version 1 required by user but not provided by server"));
2260 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2261 bombout(("SSH protocol version 2 required by user but not provided by server"));
2268 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2270 * Construct a v2 version string.
2272 verstring
= dupprintf("SSH-2.0-%s\015\012", sshver
);
2276 * Construct a v1 version string.
2278 verstring
= dupprintf("SSH-%s-%s\012",
2279 (ssh_versioncmp(s
->version
, "1.5") <= 0 ?
2280 s
->version
: "1.5"),
2285 ssh_fix_verstring(verstring
);
2287 if (ssh
->version
== 2) {
2289 * Hash our version string and their version string.
2291 SHA_Init(&ssh
->exhashbase
);
2292 sha_string(&ssh
->exhashbase
, verstring
,
2293 strcspn(verstring
, "\015\012"));
2294 sha_string(&ssh
->exhashbase
, s
->vstring
,
2295 strcspn(s
->vstring
, "\015\012"));
2298 * Initialise SSHv2 protocol.
2300 ssh
->protocol
= ssh2_protocol
;
2301 ssh2_protocol_setup(ssh
);
2302 ssh
->s_rdpkt
= ssh2_rdpkt
;
2305 * Initialise SSHv1 protocol.
2307 ssh
->protocol
= ssh1_protocol
;
2308 ssh1_protocol_setup(ssh
);
2309 ssh
->s_rdpkt
= ssh1_rdpkt
;
2311 logeventf(ssh
, "We claim version: %.*s",
2312 strcspn(verstring
, "\015\012"), verstring
);
2313 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2317 logeventf(ssh
, "Using SSH protocol version %d", ssh
->version
);
2319 update_specials_menu(ssh
->frontend
);
2320 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2321 ssh
->pinger
= pinger_new(&ssh
->cfg
, &ssh_backend
, ssh
);
2328 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2330 crBegin(ssh
->ssh_gotdata_crstate
);
2333 * To begin with, feed the characters one by one to the
2334 * protocol initialisation / selection function do_ssh_init().
2335 * When that returns 0, we're done with the initial greeting
2336 * exchange and can move on to packet discipline.
2339 int ret
; /* need not be kept across crReturn */
2341 crReturnV
; /* more data please */
2342 ret
= do_ssh_init(ssh
, *data
);
2350 * We emerge from that loop when the initial negotiation is
2351 * over and we have selected an s_rdpkt function. Now pass
2352 * everything to s_rdpkt, and then pass the resulting packets
2353 * to the proper protocol handler.
2358 while (datalen
> 0) {
2359 struct Packet
*pktin
= ssh
->s_rdpkt(ssh
, &data
, &datalen
);
2361 ssh
->protocol(ssh
, NULL
, 0, pktin
);
2362 ssh_free_packet(pktin
);
2364 if (ssh
->state
== SSH_STATE_CLOSED
)
2372 static int ssh_do_close(Ssh ssh
, int notify_exit
)
2375 struct ssh_channel
*c
;
2377 ssh
->state
= SSH_STATE_CLOSED
;
2382 notify_remote_exit(ssh
->frontend
);
2387 * Now we must shut down any port and X forwardings going
2388 * through this connection.
2390 if (ssh
->channels
) {
2391 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2394 x11_close(c
->u
.x11
.s
);
2397 pfd_close(c
->u
.pfd
.s
);
2400 del234(ssh
->channels
, c
);
2401 if (ssh
->version
== 2)
2402 bufchain_clear(&c
->v
.v2
.outbuffer
);
2410 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2413 Ssh ssh
= (Ssh
) plug
;
2414 int need_notify
= ssh_do_close(ssh
, FALSE
);
2416 if (!error_msg
&& !ssh
->close_expected
) {
2417 error_msg
= "Server unexpectedly closed network connection";
2421 /* A socket error has occurred. */
2422 logevent(error_msg
);
2423 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2425 logevent("Server closed network connection");
2428 notify_remote_exit(ssh
->frontend
);
2432 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2434 Ssh ssh
= (Ssh
) plug
;
2435 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2436 if (ssh
->state
== SSH_STATE_CLOSED
) {
2437 ssh_do_close(ssh
, TRUE
);
2443 static void ssh_sent(Plug plug
, int bufsize
)
2445 Ssh ssh
= (Ssh
) plug
;
2447 * If the send backlog on the SSH socket itself clears, we
2448 * should unthrottle the whole world if it was throttled.
2450 if (bufsize
< SSH_MAX_BACKLOG
)
2451 ssh_throttle_all(ssh
, 0, bufsize
);
2455 * Connect to specified host and port.
2456 * Returns an error message, or NULL on success.
2457 * Also places the canonical host name into `realhost'. It must be
2458 * freed by the caller.
2460 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2461 char **realhost
, int nodelay
, int keepalive
)
2463 static const struct plug_function_table fn_table
= {
2473 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2474 if (!ssh
->savedhost
)
2475 fatalbox("Out of memory");
2476 strcpy(ssh
->savedhost
, host
);
2479 port
= 22; /* default ssh port */
2480 ssh
->savedport
= port
;
2485 logeventf(ssh
, "Looking up host \"%s\"%s", host
,
2486 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV4 ?
" (IPv4)" :
2487 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV6 ?
" (IPv6)" : "")));
2488 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
,
2489 ssh
->cfg
.addressfamily
);
2490 if ((err
= sk_addr_error(addr
)) != NULL
) {
2500 sk_getaddr(addr
, addrbuf
, 100);
2501 logeventf(ssh
, "Connecting to %s port %d", addrbuf
, port
);
2503 ssh
->fn
= &fn_table
;
2504 ssh
->s
= new_connection(addr
, *realhost
, port
,
2505 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2506 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2508 notify_remote_exit(ssh
->frontend
);
2516 * Throttle or unthrottle the SSH connection.
2518 static void ssh1_throttle(Ssh ssh
, int adjust
)
2520 int old_count
= ssh
->v1_throttle_count
;
2521 ssh
->v1_throttle_count
+= adjust
;
2522 assert(ssh
->v1_throttle_count
>= 0);
2523 if (ssh
->v1_throttle_count
&& !old_count
) {
2524 sk_set_frozen(ssh
->s
, 1);
2525 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2526 sk_set_frozen(ssh
->s
, 0);
2531 * Throttle or unthrottle _all_ local data streams (for when sends
2532 * on the SSH connection itself back up).
2534 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2537 struct ssh_channel
*c
;
2539 if (enable
== ssh
->throttled_all
)
2541 ssh
->throttled_all
= enable
;
2542 ssh
->overall_bufsize
= bufsize
;
2545 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2547 case CHAN_MAINSESSION
:
2549 * This is treated separately, outside the switch.
2553 x11_override_throttle(c
->u
.x11
.s
, enable
);
2556 /* Agent channels require no buffer management. */
2559 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2566 * Username and password input, abstracted off into routines
2567 * reusable in several places - even between SSH1 and SSH2.
2570 /* Set up a username or password input loop on a given buffer. */
2571 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2573 ssh
->userpass_input_buffer
= buffer
;
2574 ssh
->userpass_input_buflen
= buflen
;
2575 ssh
->userpass_input_bufpos
= 0;
2576 ssh
->userpass_input_echo
= echo
;
2580 * Process some terminal data in the course of username/password
2581 * input. Returns >0 for success (line of input returned in
2582 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2583 * for inconclusive (keep waiting for more input please).
2585 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2590 switch (c
= *in
++) {
2593 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2594 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2599 if (ssh
->userpass_input_bufpos
> 0) {
2600 if (ssh
->userpass_input_echo
)
2601 c_write_str(ssh
, "\b \b");
2602 ssh
->userpass_input_bufpos
--;
2607 while (ssh
->userpass_input_bufpos
> 0) {
2608 if (ssh
->userpass_input_echo
)
2609 c_write_str(ssh
, "\b \b");
2610 ssh
->userpass_input_bufpos
--;
2619 * This simplistic check for printability is disabled
2620 * when we're doing password input, because some people
2621 * have control characters in their passwords.o
2623 if ((!ssh
->userpass_input_echo
||
2624 (c
>= ' ' && c
<= '~') ||
2625 ((unsigned char) c
>= 160))
2626 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2627 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2628 if (ssh
->userpass_input_echo
)
2629 c_write(ssh
, &c
, 1);
2637 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2639 Ssh ssh
= (Ssh
) sshv
;
2641 ssh
->agent_response
= reply
;
2642 ssh
->agent_response_len
= replylen
;
2644 if (ssh
->version
== 1)
2645 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2647 do_ssh2_authconn(ssh
, NULL
, -1, NULL
);
2650 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2652 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2654 void *sentreply
= reply
;
2657 /* Fake SSH_AGENT_FAILURE. */
2658 sentreply
= "\0\0\0\1\5";
2661 if (ssh
->version
== 2) {
2662 ssh2_add_channel_data(c
, sentreply
, replylen
);
2665 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2666 PKT_INT
, c
->remoteid
,
2669 PKT_DATA
, sentreply
, replylen
,
2678 * Handle the key exchange and user authentication phases.
2680 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
2681 struct Packet
*pktin
)
2684 unsigned char cookie
[8], *ptr
;
2685 struct RSAKey servkey
, hostkey
;
2686 struct MD5Context md5c
;
2687 struct do_ssh1_login_state
{
2689 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2690 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2691 int tried_publickey
, tried_agent
;
2692 int tis_auth_refused
, ccard_auth_refused
;
2693 unsigned char session_id
[16];
2696 void *publickey_blob
;
2697 int publickey_bloblen
;
2703 unsigned char request
[5], *response
, *p
;
2712 crState(do_ssh1_login_state
);
2714 crBegin(ssh
->do_ssh1_login_crstate
);
2719 if (pktin
->type
!= SSH1_SMSG_PUBLIC_KEY
) {
2720 bombout(("Public key packet not received"));
2724 logevent("Received public keys");
2726 ptr
= ssh_pkt_getdata(pktin
, 8);
2728 bombout(("SSH1 public key packet stopped before random cookie"));
2731 memcpy(cookie
, ptr
, 8);
2733 if (!ssh1_pkt_getrsakey(pktin
, &servkey
, &s
->keystr1
) ||
2734 !ssh1_pkt_getrsakey(pktin
, &hostkey
, &s
->keystr2
)) {
2735 bombout(("Failed to read SSH1 public keys from public key packet"));
2740 * Log the host key fingerprint.
2744 logevent("Host key fingerprint is:");
2745 strcpy(logmsg
, " ");
2746 hostkey
.comment
= NULL
;
2747 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2748 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2752 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(pktin
);
2753 s
->supported_ciphers_mask
= ssh_pkt_getuint32(pktin
);
2754 s
->supported_auths_mask
= ssh_pkt_getuint32(pktin
);
2756 ssh
->v1_local_protoflags
=
2757 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2758 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2761 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2762 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2763 MD5Update(&md5c
, cookie
, 8);
2764 MD5Final(s
->session_id
, &md5c
);
2766 for (i
= 0; i
< 32; i
++)
2767 ssh
->session_key
[i
] = random_byte();
2770 * Verify that the `bits' and `bytes' parameters match.
2772 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
2773 servkey
.bits
> servkey
.bytes
* 8) {
2774 bombout(("SSH1 public keys were badly formatted"));
2778 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2780 s
->rsabuf
= snewn(s
->len
, unsigned char);
2782 fatalbox("Out of memory");
2785 * Verify the host key.
2789 * First format the key into a string.
2791 int len
= rsastr_len(&hostkey
);
2792 char fingerprint
[100];
2793 char *keystr
= snewn(len
, char);
2795 fatalbox("Out of memory");
2796 rsastr_fmt(keystr
, &hostkey
);
2797 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2798 verify_ssh_host_key(ssh
->frontend
,
2799 ssh
->savedhost
, ssh
->savedport
, "rsa", keystr
,
2804 for (i
= 0; i
< 32; i
++) {
2805 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2807 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2810 if (hostkey
.bytes
> servkey
.bytes
) {
2811 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
2813 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2815 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2817 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2820 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2824 logevent("Encrypted session key");
2827 int cipher_chosen
= 0, warn
= 0;
2828 char *cipher_string
= NULL
;
2830 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2831 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
2832 if (next_cipher
== CIPHER_WARN
) {
2833 /* If/when we choose a cipher, warn about it */
2835 } else if (next_cipher
== CIPHER_AES
) {
2836 /* XXX Probably don't need to mention this. */
2837 logevent("AES not supported in SSH1, skipping");
2839 switch (next_cipher
) {
2840 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2841 cipher_string
= "3DES"; break;
2842 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2843 cipher_string
= "Blowfish"; break;
2844 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2845 cipher_string
= "single-DES"; break;
2847 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2851 if (!cipher_chosen
) {
2852 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2853 bombout(("Server violates SSH 1 protocol by not "
2854 "supporting 3DES encryption"));
2856 /* shouldn't happen */
2857 bombout(("No supported ciphers found"));
2861 /* Warn about chosen cipher if necessary. */
2863 sk_set_frozen(ssh
->s
, 1);
2864 askalg(ssh
->frontend
, "cipher", cipher_string
);
2865 sk_set_frozen(ssh
->s
, 0);
2869 switch (s
->cipher_type
) {
2870 case SSH_CIPHER_3DES
:
2871 logevent("Using 3DES encryption");
2873 case SSH_CIPHER_DES
:
2874 logevent("Using single-DES encryption");
2876 case SSH_CIPHER_BLOWFISH
:
2877 logevent("Using Blowfish encryption");
2881 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
2882 PKT_CHAR
, s
->cipher_type
,
2883 PKT_DATA
, cookie
, 8,
2884 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
2885 PKT_DATA
, s
->rsabuf
, s
->len
,
2886 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
2888 logevent("Trying to enable encryption...");
2892 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2893 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
2895 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
2896 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
2897 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
2899 ssh
->crcda_ctx
= crcda_make_context();
2900 logevent("Installing CRC compensation attack detector");
2902 if (servkey
.modulus
) {
2903 sfree(servkey
.modulus
);
2904 servkey
.modulus
= NULL
;
2906 if (servkey
.exponent
) {
2907 sfree(servkey
.exponent
);
2908 servkey
.exponent
= NULL
;
2910 if (hostkey
.modulus
) {
2911 sfree(hostkey
.modulus
);
2912 hostkey
.modulus
= NULL
;
2914 if (hostkey
.exponent
) {
2915 sfree(hostkey
.exponent
);
2916 hostkey
.exponent
= NULL
;
2920 if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
2921 bombout(("Encryption not successfully enabled"));
2925 logevent("Successfully started encryption");
2929 if (!*ssh
->cfg
.username
) {
2930 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2931 if (!ssh_get_line("login as: ",
2932 s
->username
, sizeof(s
->username
), FALSE
)) {
2934 * get_line failed to get a username.
2937 logevent("No username provided. Abandoning session.");
2938 ssh
->close_expected
= TRUE
;
2939 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2943 int ret
; /* need not be kept over crReturn */
2944 c_write_str(ssh
, "login as: ");
2947 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
2949 crWaitUntil(!pktin
);
2950 ret
= process_userpass_input(ssh
, in
, inlen
);
2954 c_write_str(ssh
, "\r\n");
2957 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
2958 s
->username
[sizeof(s
->username
)-1] = '\0';
2961 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
2963 char userlog
[22 + sizeof(s
->username
)];
2964 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
2966 if (flags
& FLAG_INTERACTIVE
&&
2967 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2968 strcat(userlog
, "\r\n");
2969 c_write_str(ssh
, userlog
);
2976 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2977 /* We must not attempt PK auth. Pretend we've already tried it. */
2978 s
->tried_publickey
= s
->tried_agent
= 1;
2980 s
->tried_publickey
= s
->tried_agent
= 0;
2982 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
2983 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
2984 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
2985 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
2986 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
2987 s
->publickey_blob
= NULL
;
2989 s
->publickey_blob
= NULL
;
2991 while (pktin
->type
== SSH1_SMSG_FAILURE
) {
2992 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2994 if (agent_exists() && !s
->tried_agent
) {
2996 * Attempt RSA authentication using Pageant.
3002 logevent("Pageant is running. Requesting keys.");
3004 /* Request the keys held by the agent. */
3005 PUT_32BIT(s
->request
, 1);
3006 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
3007 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
3008 ssh_agent_callback
, ssh
)) {
3012 bombout(("Unexpected data from server while waiting"
3013 " for agent response"));
3016 } while (pktin
|| inlen
> 0);
3017 r
= ssh
->agent_response
;
3018 s
->responselen
= ssh
->agent_response_len
;
3020 s
->response
= (unsigned char *) r
;
3021 if (s
->response
&& s
->responselen
>= 5 &&
3022 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
3023 s
->p
= s
->response
+ 5;
3024 s
->nkeys
= GET_32BIT(s
->p
);
3028 sprintf(buf
, "Pageant has %d SSH1 keys", s
->nkeys
);
3031 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
3034 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
3037 if (s
->publickey_blob
&&
3038 !memcmp(s
->p
, s
->publickey_blob
,
3039 s
->publickey_bloblen
)) {
3040 logevent("This key matches configured key file");
3041 s
->tried_publickey
= 1;
3046 do { /* do while (0) to make breaking easy */
3047 n
= ssh1_read_bignum
3048 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3053 n
= ssh1_read_bignum
3054 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3059 if (s
->responselen
- (s
->p
-s
->response
) < 4)
3061 s
->commentlen
= GET_32BIT(s
->p
);
3063 if (s
->responselen
- (s
->p
-s
->response
) <
3066 s
->commentp
= (char *)s
->p
;
3067 s
->p
+= s
->commentlen
;
3071 logevent("Pageant key list packet was truncated");
3075 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3076 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3078 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3079 logevent("Key refused");
3082 logevent("Received RSA challenge");
3083 if ((s
->challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3084 bombout(("Server's RSA challenge was badly formatted"));
3089 char *agentreq
, *q
, *ret
;
3092 len
= 1 + 4; /* message type, bit count */
3093 len
+= ssh1_bignum_length(s
->key
.exponent
);
3094 len
+= ssh1_bignum_length(s
->key
.modulus
);
3095 len
+= ssh1_bignum_length(s
->challenge
);
3096 len
+= 16; /* session id */
3097 len
+= 4; /* response format */
3098 agentreq
= snewn(4 + len
, char);
3099 PUT_32BIT(agentreq
, len
);
3101 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
3102 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
3104 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
3105 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
3106 q
+= ssh1_write_bignum(q
, s
->challenge
);
3107 memcpy(q
, s
->session_id
, 16);
3109 PUT_32BIT(q
, 1); /* response format */
3110 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
3111 ssh_agent_callback
, ssh
)) {
3116 bombout(("Unexpected data from server"
3117 " while waiting for agent"
3121 } while (pktin
|| inlen
> 0);
3122 vret
= ssh
->agent_response
;
3123 retlen
= ssh
->agent_response_len
;
3128 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
3129 logevent("Sending Pageant's response");
3130 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3131 PKT_DATA
, ret
+ 5, 16,
3135 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
3137 ("Pageant's response accepted");
3138 if (flags
& FLAG_VERBOSE
) {
3139 c_write_str(ssh
, "Authenticated using"
3141 c_write(ssh
, s
->commentp
,
3143 c_write_str(ssh
, "\" from agent\r\n");
3148 ("Pageant's response not accepted");
3151 ("Pageant failed to answer challenge");
3155 logevent("No reply received from Pageant");
3158 freebn(s
->key
.exponent
);
3159 freebn(s
->key
.modulus
);
3160 freebn(s
->challenge
);
3169 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
3170 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
3172 if (ssh
->cfg
.try_tis_auth
&&
3173 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3174 !s
->tis_auth_refused
) {
3175 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3176 logevent("Requested TIS authentication");
3177 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3179 if (pktin
->type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3180 logevent("TIS authentication declined");
3181 if (flags
& FLAG_INTERACTIVE
)
3182 c_write_str(ssh
, "TIS authentication refused.\r\n");
3183 s
->tis_auth_refused
= 1;
3189 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3191 bombout(("TIS challenge packet was badly formed"));
3194 logevent("Received TIS challenge");
3195 if (challengelen
> sizeof(s
->prompt
) - 1)
3196 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3197 memcpy(s
->prompt
, challenge
, challengelen
);
3198 /* Prompt heuristic comes from OpenSSH */
3199 strncpy(s
->prompt
+ challengelen
,
3200 memchr(s
->prompt
, '\n', challengelen
) ?
3201 "": "\r\nResponse: ",
3202 (sizeof s
->prompt
) - challengelen
);
3203 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
3206 if (ssh
->cfg
.try_tis_auth
&&
3207 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3208 !s
->ccard_auth_refused
) {
3209 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3210 logevent("Requested CryptoCard authentication");
3211 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3213 if (pktin
->type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3214 logevent("CryptoCard authentication declined");
3215 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3216 s
->ccard_auth_refused
= 1;
3222 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3224 bombout(("CryptoCard challenge packet was badly formed"));
3227 logevent("Received CryptoCard challenge");
3228 if (challengelen
> sizeof(s
->prompt
) - 1)
3229 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3230 memcpy(s
->prompt
, challenge
, challengelen
);
3231 strncpy(s
->prompt
+ challengelen
,
3232 memchr(s
->prompt
, '\n', challengelen
) ?
3233 "" : "\r\nResponse: ",
3234 sizeof(s
->prompt
) - challengelen
);
3235 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
3238 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3239 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
3240 s
->username
, ssh
->savedhost
);
3242 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3243 char *comment
= NULL
;
3246 if (flags
& FLAG_VERBOSE
)
3247 c_write_str(ssh
, "Trying public key authentication.\r\n");
3248 logeventf(ssh
, "Trying public key \"%s\"",
3249 filename_to_str(&ssh
->cfg
.keyfile
));
3250 type
= key_type(&ssh
->cfg
.keyfile
);
3251 if (type
!= SSH_KEYTYPE_SSH1
) {
3252 sprintf(msgbuf
, "Key is of wrong type (%s)",
3253 key_type_to_str(type
));
3255 c_write_str(ssh
, msgbuf
);
3256 c_write_str(ssh
, "\r\n");
3257 s
->tried_publickey
= 1;
3260 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
3261 if (flags
& FLAG_VERBOSE
)
3262 c_write_str(ssh
, "No passphrase required.\r\n");
3265 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
3270 * Show password prompt, having first obtained it via a TIS
3271 * or CryptoCard exchange if we're doing TIS or CryptoCard
3275 if (!ssh_get_line(s
->prompt
, s
->password
,
3276 sizeof(s
->password
), TRUE
)) {
3278 * get_line failed to get a password (for example
3279 * because one was supplied on the command line
3280 * which has already failed to work). Terminate.
3282 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
3283 PKT_STR
, "No more passwords available to try",
3285 logevent("Unable to authenticate");
3286 connection_fatal(ssh
->frontend
, "Unable to authenticate");
3287 ssh
->close_expected
= TRUE
;
3288 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3292 /* Prompt may have come from server. We've munged it a bit, so
3293 * we know it to be zero-terminated at least once. */
3294 int ret
; /* need not be saved over crReturn */
3295 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3298 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3300 crWaitUntil(!pktin
);
3301 ret
= process_userpass_input(ssh
, in
, inlen
);
3305 c_write_str(ssh
, "\r\n");
3309 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3311 * Try public key authentication with the specified
3314 s
->tried_publickey
= 1;
3317 const char *error
= NULL
;
3318 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3321 c_write_str(ssh
, "Couldn't load private key from ");
3322 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3323 c_write_str(ssh
, " (");
3324 c_write_str(ssh
, error
);
3325 c_write_str(ssh
, ").\r\n");
3326 continue; /* go and try password */
3329 c_write_str(ssh
, "Wrong passphrase.\r\n");
3330 s
->tried_publickey
= 0;
3331 continue; /* try again */
3336 * Send a public key attempt.
3338 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3339 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3342 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3343 c_write_str(ssh
, "Server refused our public key.\r\n");
3344 continue; /* go and try password */
3346 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3347 bombout(("Bizarre response to offer of public key"));
3353 unsigned char buffer
[32];
3354 Bignum challenge
, response
;
3356 if ((challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3357 bombout(("Server's RSA challenge was badly formatted"));
3360 response
= rsadecrypt(challenge
, &s
->key
);
3361 freebn(s
->key
.private_exponent
);/* burn the evidence */
3363 for (i
= 0; i
< 32; i
++) {
3364 buffer
[i
] = bignum_byte(response
, 31 - i
);
3368 MD5Update(&md5c
, buffer
, 32);
3369 MD5Update(&md5c
, s
->session_id
, 16);
3370 MD5Final(buffer
, &md5c
);
3372 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3373 PKT_DATA
, buffer
, 16, PKT_END
);
3380 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3381 if (flags
& FLAG_VERBOSE
)
3382 c_write_str(ssh
, "Failed to authenticate with"
3383 " our public key.\r\n");
3384 continue; /* go and try password */
3385 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3386 bombout(("Bizarre response to RSA authentication response"));
3390 break; /* we're through! */
3392 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3394 * Defence against traffic analysis: we send a
3395 * whole bunch of packets containing strings of
3396 * different lengths. One of these strings is the
3397 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3398 * The others are all random data in
3399 * SSH1_MSG_IGNORE packets. This way a passive
3400 * listener can't tell which is the password, and
3401 * hence can't deduce the password length.
3403 * Anybody with a password length greater than 16
3404 * bytes is going to have enough entropy in their
3405 * password that a listener won't find it _that_
3406 * much help to know how long it is. So what we'll
3409 * - if password length < 16, we send 15 packets
3410 * containing string lengths 1 through 15
3412 * - otherwise, we let N be the nearest multiple
3413 * of 8 below the password length, and send 8
3414 * packets containing string lengths N through
3415 * N+7. This won't obscure the order of
3416 * magnitude of the password length, but it will
3417 * introduce a bit of extra uncertainty.
3419 * A few servers (the old 1.2.18 through 1.2.22)
3420 * can't deal with SSH1_MSG_IGNORE. For these
3421 * servers, we need an alternative defence. We make
3422 * use of the fact that the password is interpreted
3423 * as a C string: so we can append a NUL, then some
3426 * One server (a Cisco one) can deal with neither
3427 * SSH1_MSG_IGNORE _nor_ a padded password string.
3428 * For this server we are left with no defences
3429 * against password length sniffing.
3431 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3433 * The server can deal with SSH1_MSG_IGNORE, so
3434 * we can use the primary defence.
3436 int bottom
, top
, pwlen
, i
;
3439 pwlen
= strlen(s
->password
);
3441 bottom
= 0; /* zero length passwords are OK! :-) */
3444 bottom
= pwlen
& ~7;
3448 assert(pwlen
>= bottom
&& pwlen
<= top
);
3450 randomstr
= snewn(top
+ 1, char);
3452 for (i
= bottom
; i
<= top
; i
++) {
3454 defer_packet(ssh
, s
->pwpkt_type
,
3455 PKTT_PASSWORD
, PKT_STR
, s
->password
,
3456 PKTT_OTHER
, PKT_END
);
3458 for (j
= 0; j
< i
; j
++) {
3460 randomstr
[j
] = random_byte();
3461 } while (randomstr
[j
] == '\0');
3463 randomstr
[i
] = '\0';
3464 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3465 PKT_STR
, randomstr
, PKT_END
);
3468 logevent("Sending password with camouflage packets");
3469 ssh_pkt_defersend(ssh
);
3472 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3474 * The server can't deal with SSH1_MSG_IGNORE
3475 * but can deal with padded passwords, so we
3476 * can use the secondary defence.
3482 len
= strlen(s
->password
);
3483 if (len
< sizeof(string
)) {
3485 strcpy(string
, s
->password
);
3486 len
++; /* cover the zero byte */
3487 while (len
< sizeof(string
)) {
3488 string
[len
++] = (char) random_byte();
3493 logevent("Sending length-padded password");
3494 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3495 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3496 PKTT_OTHER
, PKT_END
);
3499 * The server has _both_
3500 * BUG_CHOKES_ON_SSH1_IGNORE and
3501 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3502 * therefore nothing we can do.
3505 len
= strlen(s
->password
);
3506 logevent("Sending unpadded password");
3507 send_packet(ssh
, s
->pwpkt_type
,
3508 PKTT_PASSWORD
, PKT_INT
, len
,
3509 PKT_DATA
, s
->password
, len
,
3510 PKTT_OTHER
, PKT_END
);
3513 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3514 PKT_STR
, s
->password
, PKTT_OTHER
, PKT_END
);
3517 logevent("Sent password");
3518 memset(s
->password
, 0, strlen(s
->password
));
3520 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3521 if (flags
& FLAG_VERBOSE
)
3522 c_write_str(ssh
, "Access denied\r\n");
3523 logevent("Authentication refused");
3524 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3525 bombout(("Strange packet received, type %d", pktin
->type
));
3530 logevent("Authentication successful");
3535 void sshfwd_close(struct ssh_channel
*c
)
3539 if (ssh
->state
!= SSH_STATE_SESSION
) {
3540 assert(ssh
->state
== SSH_STATE_CLOSED
);
3544 if (c
&& !c
->closes
) {
3546 * If the channel's remoteid is -1, we have sent
3547 * CHANNEL_OPEN for this channel, but it hasn't even been
3548 * acknowledged by the server. So we must set a close flag
3549 * on it now, and then when the server acks the channel
3550 * open, we can close it then.
3552 if (((int)c
->remoteid
) != -1) {
3553 if (ssh
->version
== 1) {
3554 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3557 struct Packet
*pktout
;
3558 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3559 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
3560 ssh2_pkt_send(ssh
, pktout
);
3563 c
->closes
= 1; /* sent MSG_CLOSE */
3564 if (c
->type
== CHAN_X11
) {
3566 logevent("Forwarded X11 connection terminated");
3567 } else if (c
->type
== CHAN_SOCKDATA
||
3568 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3570 logevent("Forwarded port closed");
3575 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3579 if (ssh
->state
!= SSH_STATE_SESSION
) {
3580 assert(ssh
->state
== SSH_STATE_CLOSED
);
3584 if (ssh
->version
== 1) {
3585 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3586 PKT_INT
, c
->remoteid
,
3588 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3589 PKTT_OTHER
, PKT_END
);
3591 * In SSH1 we can return 0 here - implying that forwarded
3592 * connections are never individually throttled - because
3593 * the only circumstance that can cause throttling will be
3594 * the whole SSH connection backing up, in which case
3595 * _everything_ will be throttled as a whole.
3599 ssh2_add_channel_data(c
, buf
, len
);
3600 return ssh2_try_send(c
);
3604 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3608 if (ssh
->state
!= SSH_STATE_SESSION
) {
3609 assert(ssh
->state
== SSH_STATE_CLOSED
);
3613 if (ssh
->version
== 1) {
3614 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3615 c
->v
.v1
.throttling
= 0;
3616 ssh1_throttle(ssh
, -1);
3619 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3623 static void ssh_queueing_handler(Ssh ssh
, struct Packet
*pktin
)
3625 struct queued_handler
*qh
= ssh
->qhead
;
3629 assert(pktin
->type
== qh
->msg1
|| pktin
->type
== qh
->msg2
);
3632 assert(ssh
->packet_dispatch
[qh
->msg1
] == ssh_queueing_handler
);
3633 ssh
->packet_dispatch
[qh
->msg1
] = NULL
;
3636 assert(ssh
->packet_dispatch
[qh
->msg2
] == ssh_queueing_handler
);
3637 ssh
->packet_dispatch
[qh
->msg2
] = NULL
;
3641 ssh
->qhead
= qh
->next
;
3643 if (ssh
->qhead
->msg1
> 0) {
3644 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg1
] == NULL
);
3645 ssh
->packet_dispatch
[ssh
->qhead
->msg1
] = ssh_queueing_handler
;
3647 if (ssh
->qhead
->msg2
> 0) {
3648 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg2
] == NULL
);
3649 ssh
->packet_dispatch
[ssh
->qhead
->msg2
] = ssh_queueing_handler
;
3652 ssh
->qhead
= ssh
->qtail
= NULL
;
3653 ssh
->packet_dispatch
[pktin
->type
] = NULL
;
3656 qh
->handler(ssh
, pktin
, qh
->ctx
);
3661 static void ssh_queue_handler(Ssh ssh
, int msg1
, int msg2
,
3662 chandler_fn_t handler
, void *ctx
)
3664 struct queued_handler
*qh
;
3666 qh
= snew(struct queued_handler
);
3669 qh
->handler
= handler
;
3673 if (ssh
->qtail
== NULL
) {
3677 assert(ssh
->packet_dispatch
[qh
->msg1
] == NULL
);
3678 ssh
->packet_dispatch
[qh
->msg1
] = ssh_queueing_handler
;
3681 assert(ssh
->packet_dispatch
[qh
->msg2
] == NULL
);
3682 ssh
->packet_dispatch
[qh
->msg2
] = ssh_queueing_handler
;
3685 ssh
->qtail
->next
= qh
;
3690 static void ssh_rportfwd_succfail(Ssh ssh
, struct Packet
*pktin
, void *ctx
)
3692 struct ssh_rportfwd
*rpf
, *pf
= (struct ssh_rportfwd
*)ctx
;
3694 if (pktin
->type
== (ssh
->version
== 1 ? SSH1_SMSG_SUCCESS
:
3695 SSH2_MSG_REQUEST_SUCCESS
)) {
3696 logeventf(ssh
, "Remote port forwarding from %s enabled",
3699 logeventf(ssh
, "Remote port forwarding from %s refused",
3702 rpf
= del234(ssh
->rportfwds
, pf
);
3708 static void ssh_setup_portfwd(Ssh ssh
, const Config
*cfg
)
3710 const char *portfwd_strptr
= cfg
->portfwd
;
3711 struct ssh_portfwd
*epf
;
3714 if (!ssh
->portfwds
) {
3715 ssh
->portfwds
= newtree234(ssh_portcmp
);
3718 * Go through the existing port forwardings and tag them
3719 * with status==DESTROY. Any that we want to keep will be
3720 * re-enabled (status==KEEP) as we go through the
3721 * configuration and find out which bits are the same as
3724 struct ssh_portfwd
*epf
;
3726 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3727 epf
->status
= DESTROY
;
3730 while (*portfwd_strptr
) {
3731 char address_family
, type
;
3732 int sport
,dport
,sserv
,dserv
;
3733 char sports
[256], dports
[256], saddr
[256], host
[256];
3736 address_family
= 'A';
3738 if (*portfwd_strptr
== 'A' ||
3739 *portfwd_strptr
== '4' ||
3740 *portfwd_strptr
== '6')
3741 address_family
= *portfwd_strptr
++;
3742 if (*portfwd_strptr
== 'L' ||
3743 *portfwd_strptr
== 'R' ||
3744 *portfwd_strptr
== 'D')
3745 type
= *portfwd_strptr
++;
3750 while (*portfwd_strptr
&& *portfwd_strptr
!= '\t') {
3751 if (*portfwd_strptr
== ':') {
3753 * We've seen a colon in the middle of the
3754 * source port number. This means that
3755 * everything we've seen until now is the
3756 * source _address_, so we'll move it into
3757 * saddr and start sports from the beginning
3762 if (ssh
->version
== 1 && type
== 'R') {
3763 logeventf(ssh
, "SSH1 cannot handle remote source address "
3764 "spec \"%s\"; ignoring", sports
);
3766 strcpy(saddr
, sports
);
3769 if (n
< 255) sports
[n
++] = *portfwd_strptr
++;
3773 if (*portfwd_strptr
== '\t')
3776 while (*portfwd_strptr
&& *portfwd_strptr
!= ':') {
3777 if (n
< 255) host
[n
++] = *portfwd_strptr
++;
3780 if (*portfwd_strptr
== ':')
3783 while (*portfwd_strptr
) {
3784 if (n
< 255) dports
[n
++] = *portfwd_strptr
++;
3788 dport
= atoi(dports
);
3792 dport
= net_service_lookup(dports
);
3794 logeventf(ssh
, "Service lookup failed for destination"
3795 " port \"%s\"", dports
);
3799 while (*portfwd_strptr
) portfwd_strptr
++;
3801 portfwd_strptr
++; /* eat the NUL and move to next one */
3803 sport
= atoi(sports
);
3807 sport
= net_service_lookup(sports
);
3809 logeventf(ssh
, "Service lookup failed for source"
3810 " port \"%s\"", sports
);
3813 if (sport
&& dport
) {
3814 /* Set up a description of the source port. */
3815 struct ssh_portfwd
*pfrec
, *epfrec
;
3817 pfrec
= snew(struct ssh_portfwd
);
3819 pfrec
->saddr
= *saddr ?
dupstr(saddr
) : NULL
;
3820 pfrec
->sserv
= sserv ?
dupstr(sports
) : NULL
;
3821 pfrec
->sport
= sport
;
3822 pfrec
->daddr
= *host ?
dupstr(host
) : NULL
;
3823 pfrec
->dserv
= dserv ?
dupstr(dports
) : NULL
;
3824 pfrec
->dport
= dport
;
3825 pfrec
->local
= NULL
;
3826 pfrec
->remote
= NULL
;
3827 pfrec
->addressfamily
= (address_family
== '4' ? ADDRTYPE_IPV4
:
3828 address_family
== '6' ? ADDRTYPE_IPV6
:
3831 epfrec
= add234(ssh
->portfwds
, pfrec
);
3832 if (epfrec
!= pfrec
) {
3834 * We already have a port forwarding with precisely
3835 * these parameters. Hence, no need to do anything;
3836 * simply tag the existing one as KEEP.
3838 epfrec
->status
= KEEP
;
3839 free_portfwd(pfrec
);
3841 pfrec
->status
= CREATE
;
3847 * Now go through and destroy any port forwardings which were
3850 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3851 if (epf
->status
== DESTROY
) {
3854 message
= dupprintf("%s port forwarding from %s%s%d",
3855 epf
->type
== 'L' ?
"local" :
3856 epf
->type
== 'R' ?
"remote" : "dynamic",
3857 epf
->saddr ? epf
->saddr
: "",
3858 epf
->saddr ?
":" : "",
3861 if (epf
->type
!= 'D') {
3862 char *msg2
= dupprintf("%s to %s:%d", message
,
3863 epf
->daddr
, epf
->dport
);
3868 logeventf(ssh
, "Cancelling %s", message
);
3872 struct ssh_rportfwd
*rpf
= epf
->remote
;
3873 struct Packet
*pktout
;
3876 * Cancel the port forwarding at the server
3879 if (ssh
->version
== 1) {
3881 * We cannot cancel listening ports on the
3882 * server side in SSH1! There's no message
3883 * to support it. Instead, we simply remove
3884 * the rportfwd record from the local end
3885 * so that any connections the server tries
3886 * to make on it are rejected.
3889 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
3890 ssh2_pkt_addstring(pktout
, "cancel-tcpip-forward");
3891 ssh2_pkt_addbool(pktout
, 0);/* _don't_ want reply */
3893 ssh2_pkt_addstring(pktout
, epf
->saddr
);
3894 } else if (ssh
->cfg
.rport_acceptall
) {
3895 ssh2_pkt_addstring(pktout
, "0.0.0.0");
3897 ssh2_pkt_addstring(pktout
, "127.0.0.1");
3899 ssh2_pkt_adduint32(pktout
, epf
->sport
);
3900 ssh2_pkt_send(ssh
, pktout
);
3903 del234(ssh
->rportfwds
, rpf
);
3905 } else if (epf
->local
) {
3906 pfd_terminate(epf
->local
);
3909 delpos234(ssh
->portfwds
, i
);
3911 i
--; /* so we don't skip one in the list */
3915 * And finally, set up any new port forwardings (status==CREATE).
3917 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3918 if (epf
->status
== CREATE
) {
3919 char *sportdesc
, *dportdesc
;
3920 sportdesc
= dupprintf("%s%s%s%s%d%s",
3921 epf
->saddr ? epf
->saddr
: "",
3922 epf
->saddr ?
":" : "",
3923 epf
->sserv ? epf
->sserv
: "",
3924 epf
->sserv ?
"(" : "",
3926 epf
->sserv ?
")" : "");
3927 if (epf
->type
== 'D') {
3930 dportdesc
= dupprintf("%s:%s%s%d%s",
3932 epf
->dserv ? epf
->dserv
: "",
3933 epf
->dserv ?
"(" : "",
3935 epf
->dserv ?
")" : "");
3938 if (epf
->type
== 'L') {
3939 const char *err
= pfd_addforward(epf
->daddr
, epf
->dport
,
3940 epf
->saddr
, epf
->sport
,
3943 epf
->addressfamily
);
3945 logeventf(ssh
, "Local %sport %s forwarding to %s%s%s",
3946 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
3947 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
3948 sportdesc
, dportdesc
,
3949 err ?
" failed: " : "", err ? err
: "");
3950 } else if (epf
->type
== 'D') {
3951 const char *err
= pfd_addforward(NULL
, -1,
3952 epf
->saddr
, epf
->sport
,
3955 epf
->addressfamily
);
3957 logeventf(ssh
, "Local %sport %s SOCKS dynamic forwarding%s%s",
3958 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
3959 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
3961 err ?
" failed: " : "", err ? err
: "");
3963 struct ssh_rportfwd
*pf
;
3966 * Ensure the remote port forwardings tree exists.
3968 if (!ssh
->rportfwds
) {
3969 if (ssh
->version
== 1)
3970 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3972 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
3975 pf
= snew(struct ssh_rportfwd
);
3976 strncpy(pf
->dhost
, epf
->daddr
, lenof(pf
->dhost
)-1);
3977 pf
->dhost
[lenof(pf
->dhost
)-1] = '\0';
3978 pf
->dport
= epf
->dport
;
3979 pf
->sport
= epf
->sport
;
3980 if (add234(ssh
->rportfwds
, pf
) != pf
) {
3981 logeventf(ssh
, "Duplicate remote port forwarding to %s:%d",
3982 epf
->daddr
, epf
->dport
);
3985 logeventf(ssh
, "Requesting remote port %s"
3986 " forward to %s", sportdesc
, dportdesc
);
3988 pf
->sportdesc
= sportdesc
;
3993 if (ssh
->version
== 1) {
3994 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
3995 PKT_INT
, epf
->sport
,
3996 PKT_STR
, epf
->daddr
,
3997 PKT_INT
, epf
->dport
,
3999 ssh_queue_handler(ssh
, SSH1_SMSG_SUCCESS
,
4001 ssh_rportfwd_succfail
, pf
);
4003 struct Packet
*pktout
;
4004 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
4005 ssh2_pkt_addstring(pktout
, "tcpip-forward");
4006 ssh2_pkt_addbool(pktout
, 1);/* want reply */
4008 ssh2_pkt_addstring(pktout
, epf
->saddr
);
4009 } else if (ssh
->cfg
.rport_acceptall
) {
4010 ssh2_pkt_addstring(pktout
, "0.0.0.0");
4012 ssh2_pkt_addstring(pktout
, "127.0.0.1");
4014 ssh2_pkt_adduint32(pktout
, epf
->sport
);
4015 ssh2_pkt_send(ssh
, pktout
);
4017 ssh_queue_handler(ssh
, SSH2_MSG_REQUEST_SUCCESS
,
4018 SSH2_MSG_REQUEST_FAILURE
,
4019 ssh_rportfwd_succfail
, pf
);
4028 static void ssh1_smsg_stdout_stderr_data(Ssh ssh
, struct Packet
*pktin
)
4031 int stringlen
, bufsize
;
4033 ssh_pkt_getstring(pktin
, &string
, &stringlen
);
4034 if (string
== NULL
) {
4035 bombout(("Incoming terminal data packet was badly formed"));
4039 bufsize
= from_backend(ssh
->frontend
, pktin
->type
== SSH1_SMSG_STDERR_DATA
,
4041 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4042 ssh
->v1_stdout_throttling
= 1;
4043 ssh1_throttle(ssh
, +1);
4047 static void ssh1_smsg_x11_open(Ssh ssh
, struct Packet
*pktin
)
4049 /* Remote side is trying to open a channel to talk to our
4050 * X-Server. Give them back a local channel number. */
4051 struct ssh_channel
*c
;
4052 int remoteid
= ssh_pkt_getuint32(pktin
);
4054 logevent("Received X11 connect request");
4055 /* Refuse if X11 forwarding is disabled. */
4056 if (!ssh
->X11_fwd_enabled
) {
4057 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4058 PKT_INT
, remoteid
, PKT_END
);
4059 logevent("Rejected X11 connect request");
4061 c
= snew(struct ssh_channel
);
4064 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
4065 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
4066 logevent("Opening X11 forward connection failed");
4068 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4069 PKT_INT
, remoteid
, PKT_END
);
4072 ("Opening X11 forward connection succeeded");
4073 c
->remoteid
= remoteid
;
4074 c
->localid
= alloc_channel_id(ssh
);
4076 c
->v
.v1
.throttling
= 0;
4077 c
->type
= CHAN_X11
; /* identify channel type */
4078 add234(ssh
->channels
, c
);
4079 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4080 PKT_INT
, c
->remoteid
, PKT_INT
,
4081 c
->localid
, PKT_END
);
4082 logevent("Opened X11 forward channel");
4087 static void ssh1_smsg_agent_open(Ssh ssh
, struct Packet
*pktin
)
4089 /* Remote side is trying to open a channel to talk to our
4090 * agent. Give them back a local channel number. */
4091 struct ssh_channel
*c
;
4092 int remoteid
= ssh_pkt_getuint32(pktin
);
4094 /* Refuse if agent forwarding is disabled. */
4095 if (!ssh
->agentfwd_enabled
) {
4096 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4097 PKT_INT
, remoteid
, PKT_END
);
4099 c
= snew(struct ssh_channel
);
4101 c
->remoteid
= remoteid
;
4102 c
->localid
= alloc_channel_id(ssh
);
4104 c
->v
.v1
.throttling
= 0;
4105 c
->type
= CHAN_AGENT
; /* identify channel type */
4106 c
->u
.a
.lensofar
= 0;
4107 add234(ssh
->channels
, c
);
4108 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4109 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
4114 static void ssh1_msg_port_open(Ssh ssh
, struct Packet
*pktin
)
4116 /* Remote side is trying to open a channel to talk to a
4117 * forwarded port. Give them back a local channel number. */
4118 struct ssh_channel
*c
;
4119 struct ssh_rportfwd pf
, *pfp
;
4122 char *host
, buf
[1024];
4124 c
= snew(struct ssh_channel
);
4127 remoteid
= ssh_pkt_getuint32(pktin
);
4128 ssh_pkt_getstring(pktin
, &host
, &hostsize
);
4129 port
= ssh_pkt_getuint32(pktin
);
4131 if (hostsize
>= lenof(pf
.dhost
))
4132 hostsize
= lenof(pf
.dhost
)-1;
4133 memcpy(pf
.dhost
, host
, hostsize
);
4134 pf
.dhost
[hostsize
] = '\0';
4136 pfp
= find234(ssh
->rportfwds
, &pf
, NULL
);
4139 sprintf(buf
, "Rejected remote port open request for %s:%d",
4142 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4143 PKT_INT
, remoteid
, PKT_END
);
4145 sprintf(buf
, "Received remote port open request for %s:%d",
4148 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
4149 c
, &ssh
->cfg
, pfp
->pfrec
->addressfamily
);
4152 sprintf(buf
, "Port open failed: %s", e
);
4155 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4156 PKT_INT
, remoteid
, PKT_END
);
4158 c
->remoteid
= remoteid
;
4159 c
->localid
= alloc_channel_id(ssh
);
4161 c
->v
.v1
.throttling
= 0;
4162 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
4163 add234(ssh
->channels
, c
);
4164 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4165 PKT_INT
, c
->remoteid
, PKT_INT
,
4166 c
->localid
, PKT_END
);
4167 logevent("Forwarded port opened successfully");
4172 static void ssh1_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
4174 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4175 unsigned int localid
= ssh_pkt_getuint32(pktin
);
4176 struct ssh_channel
*c
;
4178 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4179 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4180 c
->remoteid
= localid
;
4181 c
->type
= CHAN_SOCKDATA
;
4182 c
->v
.v1
.throttling
= 0;
4183 pfd_confirm(c
->u
.pfd
.s
);
4186 if (c
&& c
->closes
) {
4188 * We have a pending close on this channel,
4189 * which we decided on before the server acked
4190 * the channel open. So now we know the
4191 * remoteid, we can close it again.
4193 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
4194 PKT_INT
, c
->remoteid
, PKT_END
);
4198 static void ssh1_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
4200 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4201 struct ssh_channel
*c
;
4203 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4204 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4205 logevent("Forwarded connection refused by server");
4206 pfd_close(c
->u
.pfd
.s
);
4207 del234(ssh
->channels
, c
);
4212 static void ssh1_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
4214 /* Remote side closes a channel. */
4215 unsigned i
= ssh_pkt_getuint32(pktin
);
4216 struct ssh_channel
*c
;
4217 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4218 if (c
&& ((int)c
->remoteid
) != -1) {
4221 (pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
4223 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
4224 logevent("Forwarded X11 connection terminated");
4225 assert(c
->u
.x11
.s
!= NULL
);
4226 x11_close(c
->u
.x11
.s
);
4229 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
4230 logevent("Forwarded port closed");
4231 assert(c
->u
.pfd
.s
!= NULL
);
4232 pfd_close(c
->u
.pfd
.s
);
4236 c
->closes
|= (closetype
<< 2); /* seen this message */
4237 if (!(c
->closes
& closetype
)) {
4238 send_packet(ssh
, pktin
->type
, PKT_INT
, c
->remoteid
,
4240 c
->closes
|= closetype
; /* sent it too */
4243 if (c
->closes
== 15) {
4244 del234(ssh
->channels
, c
);
4248 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4249 pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
4250 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
4255 static void ssh1_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
4257 /* Data sent down one of our channels. */
4258 int i
= ssh_pkt_getuint32(pktin
);
4261 struct ssh_channel
*c
;
4263 ssh_pkt_getstring(pktin
, &p
, &len
);
4265 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4270 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
4273 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
4276 /* Data for an agent message. Buffer it. */
4278 if (c
->u
.a
.lensofar
< 4) {
4279 unsigned int l
= min(4 - c
->u
.a
.lensofar
, len
);
4280 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
4284 c
->u
.a
.lensofar
+= l
;
4286 if (c
->u
.a
.lensofar
== 4) {
4288 4 + GET_32BIT(c
->u
.a
.msglen
);
4289 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
4291 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
4293 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
4295 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
4297 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
4301 c
->u
.a
.lensofar
+= l
;
4303 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
4306 if (agent_query(c
->u
.a
.message
,
4309 ssh_agentf_callback
, c
))
4310 ssh_agentf_callback(c
, reply
, replylen
);
4311 sfree(c
->u
.a
.message
);
4312 c
->u
.a
.lensofar
= 0;
4315 bufsize
= 0; /* agent channels never back up */
4318 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4319 c
->v
.v1
.throttling
= 1;
4320 ssh1_throttle(ssh
, +1);
4325 static void ssh1_smsg_exit_status(Ssh ssh
, struct Packet
*pktin
)
4328 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
4329 sprintf(buf
, "Server sent command exit status %d",
4332 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
4334 * In case `helpful' firewalls or proxies tack
4335 * extra human-readable text on the end of the
4336 * session which we might mistake for another
4337 * encrypted packet, we close the session once
4338 * we've sent EXIT_CONFIRMATION.
4340 ssh
->close_expected
= TRUE
;
4341 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4344 static void do_ssh1_connection(Ssh ssh
, unsigned char *in
, int inlen
,
4345 struct Packet
*pktin
)
4347 crBegin(ssh
->do_ssh1_connection_crstate
);
4349 ssh
->packet_dispatch
[SSH1_SMSG_STDOUT_DATA
] =
4350 ssh
->packet_dispatch
[SSH1_SMSG_STDERR_DATA
] =
4351 ssh1_smsg_stdout_stderr_data
;
4353 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
] =
4354 ssh1_msg_channel_open_confirmation
;
4355 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_FAILURE
] =
4356 ssh1_msg_channel_open_failure
;
4357 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE
] =
4358 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
] =
4359 ssh1_msg_channel_close
;
4360 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_DATA
] = ssh1_msg_channel_data
;
4361 ssh
->packet_dispatch
[SSH1_SMSG_EXIT_STATUS
] = ssh1_smsg_exit_status
;
4363 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
4364 logevent("Requesting agent forwarding");
4365 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
4369 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4370 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4371 bombout(("Protocol confusion"));
4373 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4374 logevent("Agent forwarding refused");
4376 logevent("Agent forwarding enabled");
4377 ssh
->agentfwd_enabled
= TRUE
;
4378 ssh
->packet_dispatch
[SSH1_SMSG_AGENT_OPEN
] = ssh1_smsg_agent_open
;
4382 if (ssh
->cfg
.x11_forward
) {
4383 char proto
[20], data
[64];
4384 logevent("Requesting X11 forwarding");
4385 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
4386 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
4387 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
4388 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
4389 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4390 PKT_STR
, proto
, PKT_STR
, data
,
4391 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
4394 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4395 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
4400 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4401 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4402 bombout(("Protocol confusion"));
4404 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4405 logevent("X11 forwarding refused");
4407 logevent("X11 forwarding enabled");
4408 ssh
->X11_fwd_enabled
= TRUE
;
4409 ssh
->packet_dispatch
[SSH1_SMSG_X11_OPEN
] = ssh1_smsg_x11_open
;
4413 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
4414 ssh
->packet_dispatch
[SSH1_MSG_PORT_OPEN
] = ssh1_msg_port_open
;
4416 if (!ssh
->cfg
.nopty
) {
4417 /* Unpick the terminal-speed string. */
4418 /* XXX perhaps we should allow no speeds to be sent. */
4419 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
4420 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
4421 /* Send the pty request. */
4422 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
4423 PKT_STR
, ssh
->cfg
.termtype
,
4424 PKT_INT
, ssh
->term_height
,
4425 PKT_INT
, ssh
->term_width
,
4426 PKT_INT
, 0, PKT_INT
, 0, /* width,height in pixels */
4427 PKT_CHAR
, 192, PKT_INT
, ssh
->ispeed
, /* TTY_OP_ISPEED */
4428 PKT_CHAR
, 193, PKT_INT
, ssh
->ospeed
, /* TTY_OP_OSPEED */
4429 PKT_CHAR
, 0, PKT_END
);
4430 ssh
->state
= SSH_STATE_INTERMED
;
4434 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4435 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4436 bombout(("Protocol confusion"));
4438 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4439 c_write_str(ssh
, "Server refused to allocate pty\r\n");
4440 ssh
->editing
= ssh
->echoing
= 1;
4442 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
4443 ssh
->ospeed
, ssh
->ispeed
);
4445 ssh
->editing
= ssh
->echoing
= 1;
4448 if (ssh
->cfg
.compression
) {
4449 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
4453 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4454 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4455 bombout(("Protocol confusion"));
4457 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4458 c_write_str(ssh
, "Server refused to compress\r\n");
4460 logevent("Started compression");
4461 ssh
->v1_compressing
= TRUE
;
4462 ssh
->cs_comp_ctx
= zlib_compress_init();
4463 logevent("Initialised zlib (RFC1950) compression");
4464 ssh
->sc_comp_ctx
= zlib_decompress_init();
4465 logevent("Initialised zlib (RFC1950) decompression");
4469 * Start the shell or command.
4471 * Special case: if the first-choice command is an SSH2
4472 * subsystem (hence not usable here) and the second choice
4473 * exists, we fall straight back to that.
4476 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
4478 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
4479 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
4480 ssh
->fallback_cmd
= TRUE
;
4483 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
4485 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
4486 logevent("Started session");
4489 ssh
->state
= SSH_STATE_SESSION
;
4490 if (ssh
->size_needed
)
4491 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
4492 if (ssh
->eof_needed
)
4493 ssh_special(ssh
, TS_EOF
);
4496 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
4498 ssh
->channels
= newtree234(ssh_channelcmp
);
4502 * By this point, most incoming packets are already being
4503 * handled by the dispatch table, and we need only pay
4504 * attention to the unusual ones.
4509 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
4510 /* may be from EXEC_SHELL on some servers */
4511 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4512 /* may be from EXEC_SHELL on some servers
4513 * if no pty is available or in other odd cases. Ignore */
4515 bombout(("Strange packet received: type %d", pktin
->type
));
4520 int len
= min(inlen
, 512);
4521 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4522 PKT_INT
, len
, PKT_DATA
, in
, len
,
4523 PKTT_OTHER
, PKT_END
);
4534 * Handle the top-level SSH2 protocol.
4536 static void ssh1_msg_debug(Ssh ssh
, struct Packet
*pktin
)
4541 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4542 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
4547 static void ssh1_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
4549 /* log reason code in disconnect message */
4553 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4554 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen
, msg
));
4557 void ssh_msg_ignore(Ssh ssh
, struct Packet
*pktin
)
4559 /* Do nothing, because we're ignoring it! Duhh. */
4562 static void ssh1_protocol_setup(Ssh ssh
)
4567 * Most messages are handled by the coroutines.
4569 for (i
= 0; i
< 256; i
++)
4570 ssh
->packet_dispatch
[i
] = NULL
;
4573 * These special message types we install handlers for.
4575 ssh
->packet_dispatch
[SSH1_MSG_DISCONNECT
] = ssh1_msg_disconnect
;
4576 ssh
->packet_dispatch
[SSH1_MSG_IGNORE
] = ssh_msg_ignore
;
4577 ssh
->packet_dispatch
[SSH1_MSG_DEBUG
] = ssh1_msg_debug
;
4580 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
4581 struct Packet
*pktin
)
4583 if (ssh
->state
== SSH_STATE_CLOSED
)
4586 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
4587 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
4591 if (!ssh
->protocol_initial_phase_done
) {
4592 if (do_ssh1_login(ssh
, in
, inlen
, pktin
))
4593 ssh
->protocol_initial_phase_done
= TRUE
;
4598 do_ssh1_connection(ssh
, in
, inlen
, pktin
);
4602 * Utility routine for decoding comma-separated strings in KEXINIT.
4604 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
4607 if (!needle
|| !haystack
) /* protect against null pointers */
4609 needlen
= strlen(needle
);
4612 * Is it at the start of the string?
4614 if (haylen
>= needlen
&& /* haystack is long enough */
4615 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4616 (haylen
== needlen
|| haystack
[needlen
] == ',')
4617 /* either , or EOS follows */
4621 * If not, search for the next comma and resume after that.
4622 * If no comma found, terminate.
4624 while (haylen
> 0 && *haystack
!= ',')
4625 haylen
--, haystack
++;
4628 haylen
--, haystack
++; /* skip over comma itself */
4633 * SSH2 key creation method.
4635 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
4636 unsigned char *sessid
, char chr
,
4637 unsigned char *keyspace
)
4640 /* First 20 bytes. */
4642 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4644 SHA_Bytes(&s
, H
, 20);
4645 SHA_Bytes(&s
, &chr
, 1);
4646 SHA_Bytes(&s
, sessid
, 20);
4647 SHA_Final(&s
, keyspace
);
4648 /* Next 20 bytes. */
4650 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4652 SHA_Bytes(&s
, H
, 20);
4653 SHA_Bytes(&s
, keyspace
, 20);
4654 SHA_Final(&s
, keyspace
+ 20);
4658 * Handle the SSH2 transport layer.
4660 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
,
4661 struct Packet
*pktin
)
4663 struct do_ssh2_transport_state
{
4664 int nbits
, pbits
, warn
;
4665 Bignum p
, g
, e
, f
, K
;
4666 int kex_init_value
, kex_reply_value
;
4667 const struct ssh_mac
**maclist
;
4669 const struct ssh2_cipher
*cscipher_tobe
;
4670 const struct ssh2_cipher
*sccipher_tobe
;
4671 const struct ssh_mac
*csmac_tobe
;
4672 const struct ssh_mac
*scmac_tobe
;
4673 const struct ssh_compress
*cscomp_tobe
;
4674 const struct ssh_compress
*sccomp_tobe
;
4675 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4676 int hostkeylen
, siglen
;
4677 void *hkey
; /* actual host key */
4678 unsigned char exchange_hash
[20];
4679 int n_preferred_kex
;
4680 const struct ssh_kex
*preferred_kex
[KEX_MAX
];
4681 int n_preferred_ciphers
;
4682 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
4683 const struct ssh_compress
*preferred_comp
;
4684 int got_session_id
, activated_authconn
;
4685 struct Packet
*pktout
;
4687 crState(do_ssh2_transport_state
);
4689 crBegin(ssh
->do_ssh2_transport_crstate
);
4691 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
4692 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
4693 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
4695 s
->got_session_id
= s
->activated_authconn
= FALSE
;
4698 * Be prepared to work around the buggy MAC problem.
4700 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
4701 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
4703 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
4706 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_KEX_MASK
;
4708 int i
, j
, commalist_started
;
4711 * Set up the preferred key exchange. (NULL => warn below here)
4713 s
->n_preferred_kex
= 0;
4714 for (i
= 0; i
< KEX_MAX
; i
++) {
4715 switch (ssh
->cfg
.ssh_kexlist
[i
]) {
4717 s
->preferred_kex
[s
->n_preferred_kex
++] =
4718 &ssh_diffiehellman_gex
;
4721 s
->preferred_kex
[s
->n_preferred_kex
++] =
4722 &ssh_diffiehellman_group14
;
4725 s
->preferred_kex
[s
->n_preferred_kex
++] =
4726 &ssh_diffiehellman_group1
;
4729 /* Flag for later. Don't bother if it's the last in
4731 if (i
< KEX_MAX
- 1) {
4732 s
->preferred_kex
[s
->n_preferred_kex
++] = NULL
;
4739 * Set up the preferred ciphers. (NULL => warn below here)
4741 s
->n_preferred_ciphers
= 0;
4742 for (i
= 0; i
< CIPHER_MAX
; i
++) {
4743 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
4744 case CIPHER_BLOWFISH
:
4745 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
4748 if (ssh
->cfg
.ssh2_des_cbc
) {
4749 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
4753 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
4756 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
4759 /* Flag for later. Don't bother if it's the last in
4761 if (i
< CIPHER_MAX
- 1) {
4762 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
4769 * Set up preferred compression.
4771 if (ssh
->cfg
.compression
)
4772 s
->preferred_comp
= &ssh_zlib
;
4774 s
->preferred_comp
= &ssh_comp_none
;
4777 * Enable queueing of outgoing auth- or connection-layer
4778 * packets while we are in the middle of a key exchange.
4780 ssh
->queueing
= TRUE
;
4783 * Flag that KEX is in progress.
4785 ssh
->kex_in_progress
= TRUE
;
4788 * Construct and send our key exchange packet.
4790 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEXINIT
);
4791 for (i
= 0; i
< 16; i
++)
4792 ssh2_pkt_addbyte(s
->pktout
, (unsigned char) random_byte());
4793 /* List key exchange algorithms. */
4794 ssh2_pkt_addstring_start(s
->pktout
);
4795 commalist_started
= 0;
4796 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4797 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4798 if (!k
) continue; /* warning flag */
4799 if (commalist_started
)
4800 ssh2_pkt_addstring_str(s
->pktout
, ",");
4801 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_kex
[i
]->name
);
4802 commalist_started
= 1;
4804 /* List server host key algorithms. */
4805 ssh2_pkt_addstring_start(s
->pktout
);
4806 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4807 ssh2_pkt_addstring_str(s
->pktout
, hostkey_algs
[i
]->name
);
4808 if (i
< lenof(hostkey_algs
) - 1)
4809 ssh2_pkt_addstring_str(s
->pktout
, ",");
4811 /* List client->server encryption algorithms. */
4812 ssh2_pkt_addstring_start(s
->pktout
);
4813 commalist_started
= 0;
4814 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4815 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4816 if (!c
) continue; /* warning flag */
4817 for (j
= 0; j
< c
->nciphers
; j
++) {
4818 if (commalist_started
)
4819 ssh2_pkt_addstring_str(s
->pktout
, ",");
4820 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4821 commalist_started
= 1;
4824 /* List server->client encryption algorithms. */
4825 ssh2_pkt_addstring_start(s
->pktout
);
4826 commalist_started
= 0;
4827 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4828 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4829 if (!c
) continue; /* warning flag */
4830 for (j
= 0; j
< c
->nciphers
; j
++) {
4831 if (commalist_started
)
4832 ssh2_pkt_addstring_str(s
->pktout
, ",");
4833 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4834 commalist_started
= 1;
4837 /* List client->server MAC algorithms. */
4838 ssh2_pkt_addstring_start(s
->pktout
);
4839 for (i
= 0; i
< s
->nmacs
; i
++) {
4840 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4841 if (i
< s
->nmacs
- 1)
4842 ssh2_pkt_addstring_str(s
->pktout
, ",");
4844 /* List server->client MAC algorithms. */
4845 ssh2_pkt_addstring_start(s
->pktout
);
4846 for (i
= 0; i
< s
->nmacs
; i
++) {
4847 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4848 if (i
< s
->nmacs
- 1)
4849 ssh2_pkt_addstring_str(s
->pktout
, ",");
4851 /* List client->server compression algorithms. */
4852 ssh2_pkt_addstring_start(s
->pktout
);
4853 assert(lenof(compressions
) > 1);
4854 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4855 for (i
= 0; i
< lenof(compressions
); i
++) {
4856 const struct ssh_compress
*c
= compressions
[i
];
4857 if (c
!= s
->preferred_comp
) {
4858 ssh2_pkt_addstring_str(s
->pktout
, ",");
4859 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4862 /* List server->client compression algorithms. */
4863 ssh2_pkt_addstring_start(s
->pktout
);
4864 assert(lenof(compressions
) > 1);
4865 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4866 for (i
= 0; i
< lenof(compressions
); i
++) {
4867 const struct ssh_compress
*c
= compressions
[i
];
4868 if (c
!= s
->preferred_comp
) {
4869 ssh2_pkt_addstring_str(s
->pktout
, ",");
4870 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4873 /* List client->server languages. Empty list. */
4874 ssh2_pkt_addstring_start(s
->pktout
);
4875 /* List server->client languages. Empty list. */
4876 ssh2_pkt_addstring_start(s
->pktout
);
4877 /* First KEX packet does _not_ follow, because we're not that brave. */
4878 ssh2_pkt_addbool(s
->pktout
, FALSE
);
4880 ssh2_pkt_adduint32(s
->pktout
, 0);
4883 ssh
->exhash
= ssh
->exhashbase
;
4884 sha_string(&ssh
->exhash
, s
->pktout
->data
+ 5, s
->pktout
->length
- 5);
4886 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
4890 if (pktin
->length
> 5)
4891 sha_string(&ssh
->exhash
, pktin
->data
+ 5, pktin
->length
- 5);
4894 * Now examine the other side's KEXINIT to see what we're up
4901 if (pktin
->type
!= SSH2_MSG_KEXINIT
) {
4902 bombout(("expected key exchange packet from server"));
4906 ssh
->hostkey
= NULL
;
4907 s
->cscipher_tobe
= NULL
;
4908 s
->sccipher_tobe
= NULL
;
4909 s
->csmac_tobe
= NULL
;
4910 s
->scmac_tobe
= NULL
;
4911 s
->cscomp_tobe
= NULL
;
4912 s
->sccomp_tobe
= NULL
;
4913 pktin
->savedpos
+= 16; /* skip garbage cookie */
4914 ssh_pkt_getstring(pktin
, &str
, &len
); /* key exchange algorithms */
4916 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4917 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4920 } else if (in_commasep_string(k
->name
, str
, len
)) {
4925 sk_set_frozen(ssh
->s
, 1);
4926 askalg(ssh
->frontend
, "key-exchange algorithm",
4928 sk_set_frozen(ssh
->s
, 0);
4934 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
4935 str ? str
: "(null)"));
4938 ssh_pkt_getstring(pktin
, &str
, &len
); /* host key algorithms */
4939 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4940 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
4941 ssh
->hostkey
= hostkey_algs
[i
];
4945 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server cipher */
4947 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4948 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4952 for (j
= 0; j
< c
->nciphers
; j
++) {
4953 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4954 s
->cscipher_tobe
= c
->list
[j
];
4959 if (s
->cscipher_tobe
) {
4961 sk_set_frozen(ssh
->s
, 1);
4962 askalg(ssh
->frontend
, "client-to-server cipher",
4963 s
->cscipher_tobe
->name
);
4964 sk_set_frozen(ssh
->s
, 0);
4969 if (!s
->cscipher_tobe
) {
4970 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
4971 str ? str
: "(null)"));
4975 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client cipher */
4977 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4978 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4982 for (j
= 0; j
< c
->nciphers
; j
++) {
4983 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4984 s
->sccipher_tobe
= c
->list
[j
];
4989 if (s
->sccipher_tobe
) {
4991 sk_set_frozen(ssh
->s
, 1);
4992 askalg(ssh
->frontend
, "server-to-client cipher",
4993 s
->sccipher_tobe
->name
);
4994 sk_set_frozen(ssh
->s
, 0);
4999 if (!s
->sccipher_tobe
) {
5000 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
5001 str ? str
: "(null)"));
5005 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server mac */
5006 for (i
= 0; i
< s
->nmacs
; i
++) {
5007 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5008 s
->csmac_tobe
= s
->maclist
[i
];
5012 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client mac */
5013 for (i
= 0; i
< s
->nmacs
; i
++) {
5014 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5015 s
->scmac_tobe
= s
->maclist
[i
];
5019 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server compression */
5020 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5021 const struct ssh_compress
*c
=
5022 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5023 if (in_commasep_string(c
->name
, str
, len
)) {
5028 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client compression */
5029 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5030 const struct ssh_compress
*c
=
5031 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5032 if (in_commasep_string(c
->name
, str
, len
)) {
5040 * Work out the number of bits of key we will need from the key
5041 * exchange. We start with the maximum key length of either
5047 csbits
= s
->cscipher_tobe
->keylen
;
5048 scbits
= s
->sccipher_tobe
->keylen
;
5049 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
5051 /* The keys only have 160-bit entropy, since they're based on
5052 * a SHA-1 hash. So cap the key size at 160 bits. */
5057 * If we're doing Diffie-Hellman group exchange, start by
5058 * requesting a group.
5060 if (!ssh
->kex
->pdata
) {
5061 logevent("Doing Diffie-Hellman group exchange");
5062 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
5064 * Work out how big a DH group we will need to allow that
5067 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
5068 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
5069 ssh2_pkt_adduint32(s
->pktout
, s
->pbits
);
5070 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5073 if (pktin
->type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
5074 bombout(("expected key exchange group packet from server"));
5077 s
->p
= ssh2_pkt_getmp(pktin
);
5078 s
->g
= ssh2_pkt_getmp(pktin
);
5079 if (!s
->p
|| !s
->g
) {
5080 bombout(("unable to read mp-ints from incoming group packet"));
5083 ssh
->kex_ctx
= dh_setup_gex(s
->p
, s
->g
);
5084 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
5085 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
5087 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP
;
5088 ssh
->kex_ctx
= dh_setup_group(ssh
->kex
);
5089 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
5090 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
5091 logeventf(ssh
, "Using Diffie-Hellman with standard group \"%s\"",
5092 ssh
->kex
->groupname
);
5095 logevent("Doing Diffie-Hellman key exchange");
5097 * Now generate and send e for Diffie-Hellman.
5099 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
5100 s
->pktout
= ssh2_pkt_init(s
->kex_init_value
);
5101 ssh2_pkt_addmp(s
->pktout
, s
->e
);
5102 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5105 if (pktin
->type
!= s
->kex_reply_value
) {
5106 bombout(("expected key exchange reply packet from server"));
5109 ssh_pkt_getstring(pktin
, &s
->hostkeydata
, &s
->hostkeylen
);
5110 s
->f
= ssh2_pkt_getmp(pktin
);
5112 bombout(("unable to parse key exchange reply packet"));
5115 ssh_pkt_getstring(pktin
, &s
->sigdata
, &s
->siglen
);
5117 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
5119 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
5120 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5121 sha_uint32(&ssh
->exhash
, s
->pbits
);
5122 sha_mpint(&ssh
->exhash
, s
->p
);
5123 sha_mpint(&ssh
->exhash
, s
->g
);
5125 sha_mpint(&ssh
->exhash
, s
->e
);
5126 sha_mpint(&ssh
->exhash
, s
->f
);
5127 sha_mpint(&ssh
->exhash
, s
->K
);
5128 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
5130 dh_cleanup(ssh
->kex_ctx
);
5131 ssh
->kex_ctx
= NULL
;
5134 debug(("Exchange hash is:\n"));
5135 dmemdump(s
->exchange_hash
, 20);
5138 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
5140 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
5141 (char *)s
->exchange_hash
, 20)) {
5142 bombout(("Server's host key did not match the signature supplied"));
5147 * Authenticate remote host: verify host key. (We've already
5148 * checked the signature of the exchange hash.)
5150 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
5151 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
5152 sk_set_frozen(ssh
->s
, 1);
5153 verify_ssh_host_key(ssh
->frontend
,
5154 ssh
->savedhost
, ssh
->savedport
, ssh
->hostkey
->keytype
,
5155 s
->keystr
, s
->fingerprint
);
5156 sk_set_frozen(ssh
->s
, 0);
5157 if (!s
->got_session_id
) { /* don't bother logging this in rekeys */
5158 logevent("Host key fingerprint is:");
5159 logevent(s
->fingerprint
);
5161 sfree(s
->fingerprint
);
5163 ssh
->hostkey
->freekey(s
->hkey
);
5166 * The exchange hash from the very first key exchange is also
5167 * the session id, used in session key construction and
5170 if (!s
->got_session_id
) {
5171 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
5172 sizeof(s
->exchange_hash
));
5173 s
->got_session_id
= TRUE
;
5177 * Send SSH2_MSG_NEWKEYS.
5179 s
->pktout
= ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
5180 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5181 ssh
->outgoing_data_size
= 0; /* start counting from here */
5184 * We've sent client NEWKEYS, so create and initialise
5185 * client-to-server session keys.
5187 if (ssh
->cs_cipher_ctx
)
5188 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
5189 ssh
->cscipher
= s
->cscipher_tobe
;
5190 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
5192 if (ssh
->cs_mac_ctx
)
5193 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
5194 ssh
->csmac
= s
->csmac_tobe
;
5195 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
5197 if (ssh
->cs_comp_ctx
)
5198 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
5199 ssh
->cscomp
= s
->cscomp_tobe
;
5200 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
5203 * Set IVs on client-to-server keys. Here we use the exchange
5204 * hash from the _first_ key exchange.
5207 unsigned char keyspace
[40];
5208 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
5209 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
5210 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
5211 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
5212 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
5213 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
5216 logeventf(ssh
, "Initialised %.200s client->server encryption",
5217 ssh
->cscipher
->text_name
);
5218 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
5219 ssh
->csmac
->text_name
);
5220 if (ssh
->cscomp
->text_name
)
5221 logeventf(ssh
, "Initialised %s compression",
5222 ssh
->cscomp
->text_name
);
5225 * Now our end of the key exchange is complete, we can send all
5226 * our queued higher-layer packets.
5228 ssh
->queueing
= FALSE
;
5229 ssh2_pkt_queuesend(ssh
);
5232 * Expect SSH2_MSG_NEWKEYS from server.
5235 if (pktin
->type
!= SSH2_MSG_NEWKEYS
) {
5236 bombout(("expected new-keys packet from server"));
5239 ssh
->incoming_data_size
= 0; /* start counting from here */
5242 * We've seen server NEWKEYS, so create and initialise
5243 * server-to-client session keys.
5245 if (ssh
->sc_cipher_ctx
)
5246 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
5247 ssh
->sccipher
= s
->sccipher_tobe
;
5248 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
5250 if (ssh
->sc_mac_ctx
)
5251 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
5252 ssh
->scmac
= s
->scmac_tobe
;
5253 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
5255 if (ssh
->sc_comp_ctx
)
5256 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
5257 ssh
->sccomp
= s
->sccomp_tobe
;
5258 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
5261 * Set IVs on server-to-client keys. Here we use the exchange
5262 * hash from the _first_ key exchange.
5265 unsigned char keyspace
[40];
5266 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
5267 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
5268 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
5269 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
5270 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
5271 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
5273 logeventf(ssh
, "Initialised %.200s server->client encryption",
5274 ssh
->sccipher
->text_name
);
5275 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
5276 ssh
->scmac
->text_name
);
5277 if (ssh
->sccomp
->text_name
)
5278 logeventf(ssh
, "Initialised %s decompression",
5279 ssh
->sccomp
->text_name
);
5282 * Free key exchange data.
5286 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5292 * Key exchange is over. Loop straight back round if we have a
5293 * deferred rekey reason.
5295 if (ssh
->deferred_rekey_reason
) {
5296 logevent(ssh
->deferred_rekey_reason
);
5298 ssh
->deferred_rekey_reason
= NULL
;
5299 goto begin_key_exchange
;
5303 * Otherwise, schedule a timer for our next rekey.
5305 ssh
->kex_in_progress
= FALSE
;
5306 ssh
->last_rekey
= GETTICKCOUNT();
5307 if (ssh
->cfg
.ssh_rekey_time
!= 0)
5308 ssh
->next_rekey
= schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5312 * If this is the first key exchange phase, we must pass the
5313 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5314 * wants to see it but because it will need time to initialise
5315 * itself before it sees an actual packet. In subsequent key
5316 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5317 * it would only confuse the layer above.
5319 if (s
->activated_authconn
) {
5322 s
->activated_authconn
= TRUE
;
5325 * Now we're encrypting. Begin returning 1 to the protocol main
5326 * function so that other things can run on top of the
5327 * transport. If we ever see a KEXINIT, we must go back to the
5330 * We _also_ go back to the start if we see pktin==NULL and
5331 * inlen==-1, because this is a special signal meaning
5332 * `initiate client-driven rekey', and `in' contains a message
5333 * giving the reason for the rekey.
5335 while (!((pktin
&& pktin
->type
== SSH2_MSG_KEXINIT
) ||
5336 (!pktin
&& inlen
== -1))) {
5341 logevent("Server initiated key re-exchange");
5344 * Special case: if the server bug is set that doesn't
5345 * allow rekeying, we give a different log message and
5346 * continue waiting. (If such a server _initiates_ a rekey,
5347 * we process it anyway!)
5349 if ((ssh
->remote_bugs
& BUG_SSH2_REKEY
)) {
5350 logeventf(ssh
, "Server bug prevents key re-exchange (%s)",
5352 /* Reset the counters, so that at least this message doesn't
5353 * hit the event log _too_ often. */
5354 ssh
->outgoing_data_size
= 0;
5355 ssh
->incoming_data_size
= 0;
5356 if (ssh
->cfg
.ssh_rekey_time
!= 0) {
5358 schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5361 goto wait_for_rekey
; /* this is utterly horrid */
5363 logeventf(ssh
, "Initiating key re-exchange (%s)", (char *)in
);
5366 goto begin_key_exchange
;
5372 * Add data to an SSH2 channel output buffer.
5374 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
5377 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
5381 * Attempt to send data on an SSH2 channel.
5383 static int ssh2_try_send(struct ssh_channel
*c
)
5386 struct Packet
*pktout
;
5388 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
5391 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
5392 if ((unsigned)len
> c
->v
.v2
.remwindow
)
5393 len
= c
->v
.v2
.remwindow
;
5394 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
5395 len
= c
->v
.v2
.remmaxpkt
;
5396 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
5397 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5398 dont_log_data(ssh
, pktout
, PKTLOG_OMIT
);
5399 ssh2_pkt_addstring_start(pktout
);
5400 ssh2_pkt_addstring_data(pktout
, data
, len
);
5401 end_log_omission(ssh
, pktout
);
5402 ssh2_pkt_send(ssh
, pktout
);
5403 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
5404 c
->v
.v2
.remwindow
-= len
;
5408 * After having sent as much data as we can, return the amount
5411 return bufchain_size(&c
->v
.v2
.outbuffer
);
5415 * Potentially enlarge the window on an SSH2 channel.
5417 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
5422 * Never send WINDOW_ADJUST for a channel that the remote side
5423 * already thinks it's closed; there's no point, since it won't
5424 * be sending any more data anyway.
5429 if (newwin
> c
->v
.v2
.locwindow
) {
5430 struct Packet
*pktout
;
5432 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5433 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5434 ssh2_pkt_adduint32(pktout
, newwin
- c
->v
.v2
.locwindow
);
5435 ssh2_pkt_send(ssh
, pktout
);
5436 c
->v
.v2
.locwindow
= newwin
;
5440 static void ssh2_msg_channel_window_adjust(Ssh ssh
, struct Packet
*pktin
)
5442 unsigned i
= ssh_pkt_getuint32(pktin
);
5443 struct ssh_channel
*c
;
5444 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5445 if (c
&& !c
->closes
)
5446 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
5449 static void ssh2_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
5452 unsigned int length
;
5453 unsigned i
= ssh_pkt_getuint32(pktin
);
5454 struct ssh_channel
*c
;
5455 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5457 return; /* nonexistent channel */
5458 if (pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5459 ssh_pkt_getuint32(pktin
) != SSH2_EXTENDED_DATA_STDERR
)
5460 return; /* extended but not stderr */
5461 ssh_pkt_getstring(pktin
, &data
, &length
);
5464 c
->v
.v2
.locwindow
-= length
;
5466 case CHAN_MAINSESSION
:
5468 from_backend(ssh
->frontend
, pktin
->type
==
5469 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5473 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5476 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5479 while (length
> 0) {
5480 if (c
->u
.a
.lensofar
< 4) {
5481 unsigned int l
= min(4 - c
->u
.a
.lensofar
, length
);
5482 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5486 c
->u
.a
.lensofar
+= l
;
5488 if (c
->u
.a
.lensofar
== 4) {
5490 4 + GET_32BIT(c
->u
.a
.msglen
);
5491 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
5493 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5495 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5497 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5499 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5503 c
->u
.a
.lensofar
+= l
;
5505 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5508 if (agent_query(c
->u
.a
.message
,
5511 ssh_agentf_callback
, c
))
5512 ssh_agentf_callback(c
, reply
, replylen
);
5513 sfree(c
->u
.a
.message
);
5514 c
->u
.a
.lensofar
= 0;
5521 * If we are not buffering too much data,
5522 * enlarge the window again at the remote side.
5524 if (bufsize
< OUR_V2_WINSIZE
)
5525 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5529 static void ssh2_msg_channel_eof(Ssh ssh
, struct Packet
*pktin
)
5531 unsigned i
= ssh_pkt_getuint32(pktin
);
5532 struct ssh_channel
*c
;
5534 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5536 return; /* nonexistent channel */
5538 if (c
->type
== CHAN_X11
) {
5540 * Remote EOF on an X11 channel means we should
5541 * wrap up and close the channel ourselves.
5543 x11_close(c
->u
.x11
.s
);
5545 } else if (c
->type
== CHAN_AGENT
) {
5547 } else if (c
->type
== CHAN_SOCKDATA
) {
5548 pfd_close(c
->u
.pfd
.s
);
5553 static void ssh2_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
5555 unsigned i
= ssh_pkt_getuint32(pktin
);
5556 struct ssh_channel
*c
;
5557 struct Packet
*pktout
;
5559 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5560 if (!c
|| ((int)c
->remoteid
) == -1) {
5561 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5562 c ?
"half-open" : "nonexistent", i
));
5565 /* Do pre-close processing on the channel. */
5567 case CHAN_MAINSESSION
:
5568 ssh
->mainchan
= NULL
;
5569 update_specials_menu(ssh
->frontend
);
5572 if (c
->u
.x11
.s
!= NULL
)
5573 x11_close(c
->u
.x11
.s
);
5580 if (c
->u
.pfd
.s
!= NULL
)
5581 pfd_close(c
->u
.pfd
.s
);
5585 if (c
->closes
== 0) {
5586 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5587 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5588 ssh2_pkt_send(ssh
, pktout
);
5590 del234(ssh
->channels
, c
);
5591 bufchain_clear(&c
->v
.v2
.outbuffer
);
5595 * See if that was the last channel left open.
5596 * (This is only our termination condition if we're
5597 * not running in -N mode.)
5599 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
5600 logevent("All channels closed. Disconnecting");
5603 * We used to send SSH_MSG_DISCONNECT here,
5604 * because I'd believed that _every_ conforming
5605 * SSH2 connection had to end with a disconnect
5606 * being sent by at least one side; apparently
5607 * I was wrong and it's perfectly OK to
5608 * unceremoniously slam the connection shut
5609 * when you're done, and indeed OpenSSH feels
5610 * this is more polite than sending a
5611 * DISCONNECT. So now we don't.
5613 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5614 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5615 ssh2_pkt_addstring(s
->pktout
, "All open channels closed");
5616 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
5617 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5619 ssh
->close_expected
= TRUE
;
5620 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5624 static void ssh2_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
5626 unsigned i
= ssh_pkt_getuint32(pktin
);
5627 struct ssh_channel
*c
;
5628 struct Packet
*pktout
;
5630 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5632 return; /* nonexistent channel */
5633 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5634 return; /* dunno why they're confirming this */
5635 c
->remoteid
= ssh_pkt_getuint32(pktin
);
5636 c
->type
= CHAN_SOCKDATA
;
5637 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
5638 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
5640 pfd_confirm(c
->u
.pfd
.s
);
5643 * We have a pending close on this channel,
5644 * which we decided on before the server acked
5645 * the channel open. So now we know the
5646 * remoteid, we can close it again.
5648 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5649 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5650 ssh2_pkt_send(ssh
, pktout
);
5654 static void ssh2_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
5656 static const char *const reasons
[] = {
5657 "<unknown reason code>",
5658 "Administratively prohibited",
5660 "Unknown channel type",
5661 "Resource shortage",
5663 unsigned i
= ssh_pkt_getuint32(pktin
);
5664 unsigned reason_code
;
5665 char *reason_string
;
5668 struct ssh_channel
*c
;
5669 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5671 return; /* nonexistent channel */
5672 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5673 return; /* dunno why they're failing this */
5675 reason_code
= ssh_pkt_getuint32(pktin
);
5676 if (reason_code
>= lenof(reasons
))
5677 reason_code
= 0; /* ensure reasons[reason_code] in range */
5678 ssh_pkt_getstring(pktin
, &reason_string
, &reason_length
);
5679 message
= dupprintf("Forwarded connection refused by"
5680 " server: %s [%.*s]", reasons
[reason_code
],
5681 reason_length
, reason_string
);
5685 pfd_close(c
->u
.pfd
.s
);
5687 del234(ssh
->channels
, c
);
5691 static void ssh2_msg_channel_request(Ssh ssh
, struct Packet
*pktin
)
5695 int typelen
, want_reply
;
5696 int reply
= SSH2_MSG_CHANNEL_FAILURE
; /* default */
5697 struct ssh_channel
*c
;
5698 struct Packet
*pktout
;
5700 localid
= ssh_pkt_getuint32(pktin
);
5701 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5702 want_reply
= ssh2_pkt_getbool(pktin
);
5705 * First, check that the channel exists. Otherwise,
5706 * we can instantly disconnect with a rude message.
5708 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
5711 sprintf(buf
, "Received channel request for nonexistent"
5712 " channel %d", localid
);
5714 pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5715 ssh2_pkt_adduint32(pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5716 ssh2_pkt_addstring(pktout
, buf
);
5717 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5718 ssh2_pkt_send_noqueue(ssh
, pktout
);
5719 connection_fatal(ssh
->frontend
, "%s", buf
);
5720 ssh
->close_expected
= TRUE
;
5721 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5726 * Having got the channel number, we now look at
5727 * the request type string to see if it's something
5730 if (c
== ssh
->mainchan
) {
5732 * We recognise "exit-status" and "exit-signal" on
5733 * the primary channel.
5735 if (typelen
== 11 &&
5736 !memcmp(type
, "exit-status", 11)) {
5738 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
5739 logeventf(ssh
, "Server sent command exit status %d",
5741 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5743 } else if (typelen
== 11 &&
5744 !memcmp(type
, "exit-signal", 11)) {
5746 int is_plausible
= TRUE
, is_int
= FALSE
;
5747 char *fmt_sig
= "", *fmt_msg
= "";
5749 int msglen
= 0, core
= FALSE
;
5750 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
5751 * provide an `int' for the signal, despite its
5752 * having been a `string' in the drafts since at
5753 * least 2001. (Fixed in session.c 1.147.) Try to
5754 * infer which we can safely parse it as. */
5756 unsigned char *p
= pktin
->body
+
5758 long len
= pktin
->length
- pktin
->savedpos
;
5759 unsigned long num
= GET_32BIT(p
); /* what is it? */
5760 /* If it's 0, it hardly matters; assume string */
5764 int maybe_int
= FALSE
, maybe_str
= FALSE
;
5765 #define CHECK_HYPOTHESIS(offset, result) \
5768 if (q >= 0 && q+4 <= len) { \
5769 q = q + 4 + GET_32BIT(p+q); \
5770 if (q >= 0 && q+4 <= len && \
5771 (q = q + 4 + GET_32BIT(p+q)) && q == len) \
5775 CHECK_HYPOTHESIS(4+1, maybe_int
);
5776 CHECK_HYPOTHESIS(4+num
+1, maybe_str
);
5777 #undef CHECK_HYPOTHESIS
5778 if (maybe_int
&& !maybe_str
)
5780 else if (!maybe_int
&& maybe_str
)
5783 /* Crikey. Either or neither. Panic. */
5784 is_plausible
= FALSE
;
5789 /* Old non-standard OpenSSH. */
5790 int signum
= ssh_pkt_getuint32(pktin
);
5791 fmt_sig
= dupprintf(" %d", signum
);
5793 /* As per the drafts. */
5796 ssh_pkt_getstring(pktin
, &sig
, &siglen
);
5797 /* Signal name isn't supposed to be blank, but
5798 * let's cope gracefully if it is. */
5800 fmt_sig
= dupprintf(" \"%.*s\"",
5804 core
= ssh2_pkt_getbool(pktin
);
5805 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
5807 fmt_msg
= dupprintf(" (\"%.*s\")", msglen
, msg
);
5809 /* ignore lang tag */
5810 } /* else don't attempt to parse */
5811 logeventf(ssh
, "Server exited on signal%s%s%s",
5812 fmt_sig
, core ?
" (core dumped)" : "",
5814 if (*fmt_sig
) sfree(fmt_sig
);
5815 if (*fmt_msg
) sfree(fmt_msg
);
5816 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5821 * This is a channel request we don't know
5822 * about, so we now either ignore the request
5823 * or respond with CHANNEL_FAILURE, depending
5826 reply
= SSH2_MSG_CHANNEL_FAILURE
;
5829 pktout
= ssh2_pkt_init(reply
);
5830 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5831 ssh2_pkt_send(ssh
, pktout
);
5835 static void ssh2_msg_global_request(Ssh ssh
, struct Packet
*pktin
)
5838 int typelen
, want_reply
;
5839 struct Packet
*pktout
;
5841 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5842 want_reply
= ssh2_pkt_getbool(pktin
);
5845 * We currently don't support any global requests
5846 * at all, so we either ignore the request or
5847 * respond with REQUEST_FAILURE, depending on
5851 pktout
= ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
5852 ssh2_pkt_send(ssh
, pktout
);
5856 static void ssh2_msg_channel_open(Ssh ssh
, struct Packet
*pktin
)
5864 struct ssh_channel
*c
;
5865 unsigned remid
, winsize
, pktsize
;
5866 struct Packet
*pktout
;
5868 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5869 c
= snew(struct ssh_channel
);
5872 remid
= ssh_pkt_getuint32(pktin
);
5873 winsize
= ssh_pkt_getuint32(pktin
);
5874 pktsize
= ssh_pkt_getuint32(pktin
);
5876 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5879 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5880 addrstr
= snewn(peeraddrlen
+1, char);
5881 memcpy(addrstr
, peeraddr
, peeraddrlen
);
5882 addrstr
[peeraddrlen
] = '\0';
5883 peerport
= ssh_pkt_getuint32(pktin
);
5885 logeventf(ssh
, "Received X11 connect request from %s:%d",
5888 if (!ssh
->X11_fwd_enabled
)
5889 error
= "X11 forwarding is not enabled";
5890 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
5891 ssh
->x11auth
, addrstr
, peerport
,
5892 &ssh
->cfg
) != NULL
) {
5893 error
= "Unable to open an X11 connection";
5895 logevent("Opening X11 forward connection succeeded");
5900 } else if (typelen
== 15 &&
5901 !memcmp(type
, "forwarded-tcpip", 15)) {
5902 struct ssh_rportfwd pf
, *realpf
;
5905 ssh_pkt_getstring(pktin
, &dummy
, &dummylen
);/* skip address */
5906 pf
.sport
= ssh_pkt_getuint32(pktin
);
5907 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5908 peerport
= ssh_pkt_getuint32(pktin
);
5909 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
5910 logeventf(ssh
, "Received remote port %d open request "
5911 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
5912 if (realpf
== NULL
) {
5913 error
= "Remote port is not recognised";
5915 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
5919 realpf
->pfrec
->addressfamily
);
5920 logeventf(ssh
, "Attempting to forward remote port to "
5921 "%s:%d", realpf
->dhost
, realpf
->dport
);
5923 logeventf(ssh
, "Port open failed: %s", e
);
5924 error
= "Port open failed";
5926 logevent("Forwarded port opened successfully");
5927 c
->type
= CHAN_SOCKDATA
;
5930 } else if (typelen
== 22 &&
5931 !memcmp(type
, "auth-agent@openssh.com", 3)) {
5932 if (!ssh
->agentfwd_enabled
)
5933 error
= "Agent forwarding is not enabled";
5935 c
->type
= CHAN_AGENT
; /* identify channel type */
5936 c
->u
.a
.lensofar
= 0;
5939 error
= "Unsupported channel type requested";
5942 c
->remoteid
= remid
;
5944 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
5945 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5946 ssh2_pkt_adduint32(pktout
, SSH2_OPEN_CONNECT_FAILED
);
5947 ssh2_pkt_addstring(pktout
, error
);
5948 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5949 ssh2_pkt_send(ssh
, pktout
);
5950 logeventf(ssh
, "Rejected channel open: %s", error
);
5953 c
->localid
= alloc_channel_id(ssh
);
5955 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5956 c
->v
.v2
.remwindow
= winsize
;
5957 c
->v
.v2
.remmaxpkt
= pktsize
;
5958 bufchain_init(&c
->v
.v2
.outbuffer
);
5959 add234(ssh
->channels
, c
);
5960 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
5961 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5962 ssh2_pkt_adduint32(pktout
, c
->localid
);
5963 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);
5964 ssh2_pkt_adduint32(pktout
, 0x4000UL
); /* our max pkt size */
5965 ssh2_pkt_send(ssh
, pktout
);
5970 * Handle the SSH2 userauth and connection layers.
5972 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
5973 struct Packet
*pktin
)
5975 struct do_ssh2_authconn_state
{
5977 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
5979 AUTH_KEYBOARD_INTERACTIVE
5983 AUTH_TYPE_PUBLICKEY
,
5984 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
5985 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
5987 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
5988 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
5990 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
5991 int tried_pubkey_config
, tried_agent
;
5992 int kbd_inter_running
, kbd_inter_refused
;
5994 int num_prompts
, curr_prompt
, echo
;
5999 void *publickey_blob
;
6000 int publickey_bloblen
;
6001 unsigned char request
[5], *response
, *p
;
6005 char *pkblob
, *alg
, *commentp
;
6006 int pklen
, alglen
, commentlen
;
6007 int siglen
, retlen
, len
;
6008 char *q
, *agentreq
, *ret
;
6010 int num_env
, env_left
, env_ok
;
6011 struct Packet
*pktout
;
6013 crState(do_ssh2_authconn_state
);
6015 crBegin(ssh
->do_ssh2_authconn_crstate
);
6018 * Request userauth protocol, and await a response to it.
6020 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
6021 ssh2_pkt_addstring(s
->pktout
, "ssh-userauth");
6022 ssh2_pkt_send(ssh
, s
->pktout
);
6023 crWaitUntilV(pktin
);
6024 if (pktin
->type
!= SSH2_MSG_SERVICE_ACCEPT
) {
6025 bombout(("Server refused user authentication protocol"));
6030 * We repeat this whole loop, including the username prompt,
6031 * until we manage a successful authentication. If the user
6032 * types the wrong _password_, they can be sent back to the
6033 * beginning to try another username, if this is configured on.
6034 * (If they specify a username in the config, they are never
6035 * asked, even if they do give a wrong password.)
6037 * I think this best serves the needs of
6039 * - the people who have no configuration, no keys, and just
6040 * want to try repeated (username,password) pairs until they
6041 * type both correctly
6043 * - people who have keys and configuration but occasionally
6044 * need to fall back to passwords
6046 * - people with a key held in Pageant, who might not have
6047 * logged in to a particular machine before; so they want to
6048 * type a username, and then _either_ their key will be
6049 * accepted, _or_ they will type a password. If they mistype
6050 * the username they will want to be able to get back and
6053 s
->username
[0] = '\0';
6054 s
->got_username
= FALSE
;
6059 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
6061 * We got a username last time round this loop, and
6062 * with change_username turned off we don't try to get
6065 } else if (!*ssh
->cfg
.username
) {
6066 if (ssh_get_line
&& !ssh_getline_pw_only
) {
6067 if (!ssh_get_line("login as: ",
6068 s
->username
, sizeof(s
->username
), FALSE
)) {
6070 * get_line failed to get a username.
6073 logevent("No username provided. Abandoning session.");
6074 ssh
->close_expected
= TRUE
;
6075 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6079 int ret
; /* need not be saved across crReturn */
6080 c_write_str(ssh
, "login as: ");
6082 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
6084 crWaitUntilV(!pktin
);
6085 ret
= process_userpass_input(ssh
, in
, inlen
);
6089 c_write_str(ssh
, "\r\n");
6091 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
6094 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
6095 s
->username
[sizeof(s
->username
)-1] = '\0';
6096 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
6097 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
6098 c_write_str(ssh
, stuff
);
6102 s
->got_username
= TRUE
;
6105 * Send an authentication request using method "none": (a)
6106 * just in case it succeeds, and (b) so that we know what
6107 * authentication methods we can usefully try next.
6109 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6111 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6112 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6113 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");/* service requested */
6114 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6115 ssh2_pkt_send(ssh
, s
->pktout
);
6116 s
->type
= AUTH_TYPE_NONE
;
6118 s
->we_are_in
= FALSE
;
6120 s
->tried_pubkey_config
= FALSE
;
6121 s
->tried_agent
= FALSE
;
6122 s
->kbd_inter_running
= FALSE
;
6123 s
->kbd_inter_refused
= FALSE
;
6124 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
6125 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
6127 logeventf(ssh
, "Reading private key file \"%.150s\"",
6128 filename_to_str(&ssh
->cfg
.keyfile
));
6129 keytype
= key_type(&ssh
->cfg
.keyfile
);
6130 if (keytype
== SSH_KEYTYPE_SSH2
) {
6132 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
6133 &s
->publickey_bloblen
, NULL
);
6136 logeventf(ssh
, "Unable to use this key file (%s)",
6137 key_type_to_str(keytype
));
6138 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
6140 filename_to_str(&ssh
->cfg
.keyfile
),
6141 key_type_to_str(keytype
));
6142 c_write_str(ssh
, msgbuf
);
6144 s
->publickey_blob
= NULL
;
6147 s
->publickey_blob
= NULL
;
6151 * Wait for the result of the last authentication request.
6154 crWaitUntilV(pktin
);
6155 while (pktin
->type
== SSH2_MSG_USERAUTH_BANNER
) {
6159 * Don't show the banner if we're operating in
6160 * non-verbose non-interactive mode. (It's probably
6161 * a script, which means nobody will read the
6162 * banner _anyway_, and moreover the printing of
6163 * the banner will screw up processing on the
6164 * output of (say) plink.)
6166 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
6167 ssh_pkt_getstring(pktin
, &banner
, &size
);
6169 c_write_untrusted(ssh
, banner
, size
);
6171 crWaitUntilV(pktin
);
6173 if (pktin
->type
== SSH2_MSG_USERAUTH_SUCCESS
) {
6174 logevent("Access granted");
6175 s
->we_are_in
= TRUE
;
6179 if (s
->kbd_inter_running
&&
6180 pktin
->type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6182 * This is either a further set-of-prompts packet
6183 * in keyboard-interactive authentication, or it's
6184 * the same one and we came back here with `gotit'
6185 * set. In the former case, we must reset the
6186 * curr_prompt variable.
6190 } else if (pktin
->type
== SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
) {
6191 /* FIXME: perhaps we should support this? */
6192 bombout(("PASSWD_CHANGEREQ not yet supported"));
6194 } else if (pktin
->type
!= SSH2_MSG_USERAUTH_FAILURE
) {
6195 bombout(("Strange packet received during authentication: type %d",
6203 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6204 * we can look at the string in it and know what we can
6205 * helpfully try next.
6207 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
) {
6210 ssh_pkt_getstring(pktin
, &methods
, &methlen
);
6211 s
->kbd_inter_running
= FALSE
;
6212 if (!ssh2_pkt_getbool(pktin
)) {
6214 * We have received an unequivocal Access
6215 * Denied. This can translate to a variety of
6218 * - if we'd just tried "none" authentication,
6219 * it's not worth printing anything at all
6221 * - if we'd just tried a public key _offer_,
6222 * the message should be "Server refused our
6223 * key" (or no message at all if the key
6224 * came from Pageant)
6226 * - if we'd just tried anything else, the
6227 * message really should be "Access denied".
6229 * Additionally, if we'd just tried password
6230 * authentication, we should break out of this
6231 * whole loop so as to go back to the username
6232 * prompt (iff we're configured to allow
6233 * username change attempts).
6235 if (s
->type
== AUTH_TYPE_NONE
) {
6237 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
6238 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
6239 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
6240 c_write_str(ssh
, "Server refused our key\r\n");
6241 logevent("Server refused public key");
6242 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
6243 /* server declined keyboard-interactive; ignore */
6245 c_write_str(ssh
, "Access denied\r\n");
6246 logevent("Access denied");
6247 if (s
->type
== AUTH_TYPE_PASSWORD
&&
6248 ssh
->cfg
.change_username
) {
6249 /* XXX perhaps we should allow
6250 * keyboard-interactive to do this too? */
6251 s
->we_are_in
= FALSE
;
6256 c_write_str(ssh
, "Further authentication required\r\n");
6257 logevent("Further authentication required");
6261 in_commasep_string("publickey", methods
, methlen
);
6263 in_commasep_string("password", methods
, methlen
);
6264 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
6265 in_commasep_string("keyboard-interactive", methods
, methlen
);
6269 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6273 * Most password/passphrase prompts will be
6274 * non-echoing, so we set this to 0 by default.
6275 * Exception is that some keyboard-interactive prompts
6276 * can be echoing, in which case we'll set this to 1.
6280 if (!s
->method
&& s
->can_pubkey
&&
6281 agent_exists() && !s
->tried_agent
) {
6283 * Attempt public-key authentication using Pageant.
6288 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6289 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6291 s
->tried_agent
= TRUE
;
6293 logevent("Pageant is running. Requesting keys.");
6295 /* Request the keys held by the agent. */
6296 PUT_32BIT(s
->request
, 1);
6297 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
6298 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
6299 ssh_agent_callback
, ssh
)) {
6303 bombout(("Unexpected data from server while"
6304 " waiting for agent response"));
6307 } while (pktin
|| inlen
> 0);
6308 r
= ssh
->agent_response
;
6309 s
->responselen
= ssh
->agent_response_len
;
6311 s
->response
= (unsigned char *) r
;
6312 if (s
->response
&& s
->responselen
>= 5 &&
6313 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
6314 s
->p
= s
->response
+ 5;
6315 s
->nkeys
= GET_32BIT(s
->p
);
6319 sprintf(buf
, "Pageant has %d SSH2 keys", s
->nkeys
);
6322 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
6327 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
6330 s
->pklen
= GET_32BIT(s
->p
);
6332 if (s
->publickey_blob
&&
6333 s
->pklen
== s
->publickey_bloblen
&&
6334 !memcmp(s
->p
, s
->publickey_blob
,
6335 s
->publickey_bloblen
)) {
6336 logevent("This key matches configured key file");
6337 s
->tried_pubkey_config
= 1;
6339 s
->pkblob
= (char *)s
->p
;
6341 s
->alglen
= GET_32BIT(s
->pkblob
);
6342 s
->alg
= s
->pkblob
+ 4;
6343 s
->commentlen
= GET_32BIT(s
->p
);
6345 s
->commentp
= (char *)s
->p
;
6346 s
->p
+= s
->commentlen
;
6347 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6348 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6349 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6350 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6351 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6352 ssh2_pkt_addstring_start(s
->pktout
);
6353 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6354 ssh2_pkt_addstring_start(s
->pktout
);
6355 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6356 ssh2_pkt_send(ssh
, s
->pktout
);
6358 crWaitUntilV(pktin
);
6359 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6360 logevent("Key refused");
6364 if (flags
& FLAG_VERBOSE
) {
6365 c_write_str(ssh
, "Authenticating with "
6367 c_write(ssh
, s
->commentp
, s
->commentlen
);
6368 c_write_str(ssh
, "\" from agent\r\n");
6372 * Server is willing to accept the key.
6373 * Construct a SIGN_REQUEST.
6375 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6376 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6377 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6378 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6379 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6380 ssh2_pkt_addstring_start(s
->pktout
);
6381 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6382 ssh2_pkt_addstring_start(s
->pktout
);
6383 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6385 s
->siglen
= s
->pktout
->length
- 5 + 4 + 20;
6386 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6388 s
->len
= 1; /* message type */
6389 s
->len
+= 4 + s
->pklen
; /* key blob */
6390 s
->len
+= 4 + s
->siglen
; /* data to sign */
6391 s
->len
+= 4; /* flags */
6392 s
->agentreq
= snewn(4 + s
->len
, char);
6393 PUT_32BIT(s
->agentreq
, s
->len
);
6394 s
->q
= s
->agentreq
+ 4;
6395 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
6396 PUT_32BIT(s
->q
, s
->pklen
);
6398 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
6400 PUT_32BIT(s
->q
, s
->siglen
);
6402 /* Now the data to be signed... */
6403 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6404 PUT_32BIT(s
->q
, 20);
6407 memcpy(s
->q
, ssh
->v2_session_id
, 20);
6409 memcpy(s
->q
, s
->pktout
->data
+ 5,
6410 s
->pktout
->length
- 5);
6411 s
->q
+= s
->pktout
->length
- 5;
6412 /* And finally the (zero) flags word. */
6414 if (!agent_query(s
->agentreq
, s
->len
+ 4,
6416 ssh_agent_callback
, ssh
)) {
6420 bombout(("Unexpected data from server"
6421 " while waiting for agent"
6425 } while (pktin
|| inlen
> 0);
6426 vret
= ssh
->agent_response
;
6427 s
->retlen
= ssh
->agent_response_len
;
6432 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
6433 logevent("Sending Pageant's response");
6434 ssh2_add_sigblob(ssh
, s
->pktout
,
6435 s
->pkblob
, s
->pklen
,
6437 GET_32BIT(s
->ret
+ 5));
6438 ssh2_pkt_send(ssh
, s
->pktout
);
6443 ("Pageant failed to answer challenge");
6454 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
6455 && !s
->tried_pubkey_config
) {
6456 unsigned char *pub_blob
;
6457 char *algorithm
, *comment
;
6460 s
->tried_pubkey_config
= TRUE
;
6462 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6463 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6466 * Try the public key supplied in the configuration.
6468 * First, offer the public blob to see if the server is
6469 * willing to accept it.
6472 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
6477 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6478 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6479 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6480 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6481 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6482 ssh2_pkt_addstring(s
->pktout
, algorithm
);
6483 ssh2_pkt_addstring_start(s
->pktout
);
6484 ssh2_pkt_addstring_data(s
->pktout
, (char *)pub_blob
,
6486 ssh2_pkt_send(ssh
, s
->pktout
);
6487 logevent("Offered public key");
6489 crWaitUntilV(pktin
);
6490 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6492 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
6493 continue; /* key refused; give up on it */
6496 logevent("Offer of public key accepted");
6498 * Actually attempt a serious authentication using
6501 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
6502 sprintf(s
->pwprompt
,
6503 "Passphrase for key \"%.100s\": ",
6509 if (flags
& FLAG_VERBOSE
) {
6510 c_write_str(ssh
, "Authenticating with public key \"");
6511 c_write_str(ssh
, comment
);
6512 c_write_str(ssh
, "\"\r\n");
6514 s
->method
= AUTH_PUBLICKEY_FILE
;
6518 if (!s
->method
&& s
->can_keyb_inter
&& !s
->kbd_inter_refused
&&
6519 !s
->kbd_inter_running
) {
6520 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6521 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6523 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6524 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6526 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6527 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6528 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6529 ssh2_pkt_addstring(s
->pktout
, "keyboard-interactive"); /* method */
6530 ssh2_pkt_addstring(s
->pktout
, ""); /* lang */
6531 ssh2_pkt_addstring(s
->pktout
, "");
6532 ssh2_pkt_send(ssh
, s
->pktout
);
6534 crWaitUntilV(pktin
);
6535 if (pktin
->type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6536 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
)
6538 logevent("Keyboard-interactive authentication refused");
6539 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
6540 s
->kbd_inter_refused
= TRUE
; /* don't try it again */
6544 s
->kbd_inter_running
= TRUE
;
6548 if (s
->kbd_inter_running
) {
6549 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6550 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6552 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6553 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6555 if (s
->curr_prompt
== 0) {
6557 * We've got a fresh USERAUTH_INFO_REQUEST.
6558 * Display header data, and start going through
6561 char *name
, *inst
, *lang
;
6562 int name_len
, inst_len
, lang_len
;
6564 ssh_pkt_getstring(pktin
, &name
, &name_len
);
6565 ssh_pkt_getstring(pktin
, &inst
, &inst_len
);
6566 ssh_pkt_getstring(pktin
, &lang
, &lang_len
);
6568 c_write_untrusted(ssh
, name
, name_len
);
6569 c_write_str(ssh
, "\r\n");
6572 c_write_untrusted(ssh
, inst
, inst_len
);
6573 c_write_str(ssh
, "\r\n");
6575 s
->num_prompts
= ssh_pkt_getuint32(pktin
);
6579 * If there are prompts remaining in the packet,
6580 * display one and get a response.
6582 if (s
->curr_prompt
< s
->num_prompts
) {
6586 ssh_pkt_getstring(pktin
, &prompt
, &prompt_len
);
6587 if (prompt_len
> 0) {
6588 static const char trunc
[] = "<prompt truncated>: ";
6589 static const int prlen
= sizeof(s
->pwprompt
) -
6591 if (prompt_len
> prlen
) {
6592 memcpy(s
->pwprompt
, prompt
, prlen
);
6593 strcpy(s
->pwprompt
+ prlen
, trunc
);
6595 memcpy(s
->pwprompt
, prompt
, prompt_len
);
6596 s
->pwprompt
[prompt_len
] = '\0';
6600 "<server failed to send prompt>: ");
6602 s
->echo
= ssh2_pkt_getbool(pktin
);
6608 if (!s
->method
&& s
->can_passwd
) {
6609 s
->method
= AUTH_PASSWORD
;
6610 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6611 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
6612 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
6619 if (!ssh_get_line(s
->pwprompt
, s
->password
,
6620 sizeof(s
->password
), TRUE
)) {
6622 * get_line failed to get a password (for
6623 * example because one was supplied on the
6624 * command line which has already failed to
6627 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6628 ssh2_pkt_adduint32(s
->pktout
,SSH2_DISCONNECT_BY_APPLICATION
);
6629 ssh2_pkt_addstring(s
->pktout
, "No more passwords available"
6631 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6632 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6633 logevent("Unable to authenticate");
6634 connection_fatal(ssh
->frontend
,
6635 "Unable to authenticate");
6636 ssh
->close_expected
= TRUE
;
6637 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6641 int ret
; /* need not be saved across crReturn */
6642 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
6645 setup_userpass_input(ssh
, s
->password
,
6646 sizeof(s
->password
), s
->echo
);
6648 crWaitUntilV(!pktin
);
6649 ret
= process_userpass_input(ssh
, in
, inlen
);
6653 c_write_str(ssh
, "\r\n");
6657 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
6659 * We have our passphrase. Now try the actual authentication.
6661 struct ssh2_userkey
*key
;
6662 const char *error
= NULL
;
6664 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
,
6666 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
6667 if (key
== SSH2_WRONG_PASSPHRASE
) {
6668 c_write_str(ssh
, "Wrong passphrase\r\n");
6669 s
->tried_pubkey_config
= FALSE
;
6671 c_write_str(ssh
, "Unable to load private key (");
6672 c_write_str(ssh
, error
);
6673 c_write_str(ssh
, ")\r\n");
6674 s
->tried_pubkey_config
= TRUE
;
6676 /* Send a spurious AUTH_NONE to return to the top. */
6677 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6678 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6679 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6680 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6681 ssh2_pkt_send(ssh
, s
->pktout
);
6682 s
->type
= AUTH_TYPE_NONE
;
6684 unsigned char *pkblob
, *sigblob
, *sigdata
;
6685 int pkblob_len
, sigblob_len
, sigdata_len
;
6689 * We have loaded the private key and the server
6690 * has announced that it's willing to accept it.
6691 * Hallelujah. Generate a signature and send it.
6693 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6694 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6695 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6696 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6697 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6698 ssh2_pkt_addstring(s
->pktout
, key
->alg
->name
);
6699 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
6700 ssh2_pkt_addstring_start(s
->pktout
);
6701 ssh2_pkt_addstring_data(s
->pktout
, (char *)pkblob
, pkblob_len
);
6704 * The data to be signed is:
6708 * followed by everything so far placed in the
6711 sigdata_len
= s
->pktout
->length
- 5 + 4 + 20;
6712 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6714 sigdata
= snewn(sigdata_len
, unsigned char);
6716 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6717 PUT_32BIT(sigdata
+p
, 20);
6720 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
6721 memcpy(sigdata
+p
, s
->pktout
->data
+ 5,
6722 s
->pktout
->length
- 5);
6723 p
+= s
->pktout
->length
- 5;
6724 assert(p
== sigdata_len
);
6725 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
6726 sigdata_len
, &sigblob_len
);
6727 ssh2_add_sigblob(ssh
, s
->pktout
, pkblob
, pkblob_len
,
6728 sigblob
, sigblob_len
);
6733 ssh2_pkt_send(ssh
, s
->pktout
);
6734 s
->type
= AUTH_TYPE_PUBLICKEY
;
6735 key
->alg
->freekey(key
->data
);
6737 } else if (s
->method
== AUTH_PASSWORD
) {
6739 * We send the password packet lumped tightly together with
6740 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
6741 * string long enough to make the total length of the two
6742 * packets constant. This should ensure that a passive
6743 * listener doing traffic analyis can't work out the length
6746 * For this to work, we need an assumption about the
6747 * maximum length of the password packet. I think 256 is
6748 * pretty conservative. Anyone using a password longer than
6749 * that probably doesn't have much to worry about from
6750 * people who find out how long their password is!
6752 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6753 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6754 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6755 ssh2_pkt_addstring(s
->pktout
, "password");
6756 ssh2_pkt_addbool(s
->pktout
, FALSE
);
6757 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6758 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6759 memset(s
->password
, 0, sizeof(s
->password
));
6760 end_log_omission(ssh
, s
->pktout
);
6761 ssh2_pkt_defer(ssh
, s
->pktout
);
6763 * We'll include a string that's an exact multiple of the
6764 * cipher block size. If the cipher is NULL for some
6765 * reason, we don't do this trick at all because we gain
6768 if (ssh
->cscipher
) {
6771 stringlen
= (256 - ssh
->deferred_len
);
6772 stringlen
+= ssh
->cscipher
->blksize
- 1;
6773 stringlen
-= (stringlen
% ssh
->cscipher
->blksize
);
6776 * Temporarily disable actual compression,
6777 * so we can guarantee to get this string
6778 * exactly the length we want it. The
6779 * compression-disabling routine should
6780 * return an integer indicating how many
6781 * bytes we should adjust our string length
6785 ssh
->cscomp
->disable_compression(ssh
->cs_comp_ctx
);
6787 s
->pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
6788 ssh2_pkt_addstring_start(s
->pktout
);
6789 for (i
= 0; i
< stringlen
; i
++) {
6790 char c
= (char) random_byte();
6791 ssh2_pkt_addstring_data(s
->pktout
, &c
, 1);
6793 ssh2_pkt_defer(ssh
, s
->pktout
);
6795 ssh_pkt_defersend(ssh
);
6796 logevent("Sent password");
6797 s
->type
= AUTH_TYPE_PASSWORD
;
6798 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
6799 if (s
->curr_prompt
== 0) {
6800 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
6801 ssh2_pkt_adduint32(s
->pktout
, s
->num_prompts
);
6803 if (s
->need_pw
) { /* only add pw if we just got one! */
6804 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6805 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6806 memset(s
->password
, 0, sizeof(s
->password
));
6807 end_log_omission(ssh
, s
->pktout
);
6810 if (s
->curr_prompt
>= s
->num_prompts
) {
6811 ssh2_pkt_send(ssh
, s
->pktout
);
6814 * If there are prompts remaining, we set
6815 * `gotit' so that we won't attempt to get
6816 * another packet. Then we go back round the
6817 * loop and will end up retrieving another
6818 * prompt out of the existing packet. Funky or
6823 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6825 c_write_str(ssh
, "No supported authentication methods"
6826 " left to try!\r\n");
6827 logevent("No supported authentications offered."
6829 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6830 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
6831 ssh2_pkt_addstring(s
->pktout
, "No supported authentication"
6832 " methods available");
6833 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6834 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6835 ssh
->close_expected
= TRUE
;
6836 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6840 } while (!s
->we_are_in
);
6843 * Now we're authenticated for the connection protocol. The
6844 * connection protocol will automatically have started at this
6845 * point; there's no need to send SERVICE_REQUEST.
6848 ssh
->channels
= newtree234(ssh_channelcmp
);
6851 * Set up handlers for some connection protocol messages, so we
6852 * don't have to handle them repeatedly in this coroutine.
6854 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] =
6855 ssh2_msg_channel_window_adjust
;
6856 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] =
6857 ssh2_msg_global_request
;
6860 * Create the main session channel.
6862 if (!ssh
->cfg
.ssh_no_shell
) {
6863 ssh
->mainchan
= snew(struct ssh_channel
);
6864 ssh
->mainchan
->ssh
= ssh
;
6865 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
6866 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
6867 ssh2_pkt_addstring(s
->pktout
, "session");
6868 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->localid
);
6869 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6870 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
6871 ssh2_pkt_adduint32(s
->pktout
, 0x4000UL
); /* our max pkt size */
6872 ssh2_pkt_send(ssh
, s
->pktout
);
6873 crWaitUntilV(pktin
);
6874 if (pktin
->type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
6875 bombout(("Server refused to open a session"));
6877 /* FIXME: error data comes back in FAILURE packet */
6879 if (ssh_pkt_getuint32(pktin
) != ssh
->mainchan
->localid
) {
6880 bombout(("Server's channel confirmation cited wrong channel"));
6883 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(pktin
);
6884 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
6885 ssh
->mainchan
->closes
= 0;
6886 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
6887 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
6888 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
6889 add234(ssh
->channels
, ssh
->mainchan
);
6890 update_specials_menu(ssh
->frontend
);
6891 logevent("Opened channel for session");
6893 ssh
->mainchan
= NULL
;
6896 * Now we have a channel, make dispatch table entries for
6897 * general channel-based messages.
6899 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] =
6900 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] =
6901 ssh2_msg_channel_data
;
6902 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = ssh2_msg_channel_eof
;
6903 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = ssh2_msg_channel_close
;
6904 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] =
6905 ssh2_msg_channel_open_confirmation
;
6906 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] =
6907 ssh2_msg_channel_open_failure
;
6908 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] =
6909 ssh2_msg_channel_request
;
6910 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] =
6911 ssh2_msg_channel_open
;
6914 * Potentially enable X11 forwarding.
6916 if (ssh
->mainchan
&& ssh
->cfg
.x11_forward
) {
6917 char proto
[20], data
[64];
6918 logevent("Requesting X11 forwarding");
6919 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
6920 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
6921 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
6922 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6923 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6924 ssh2_pkt_addstring(s
->pktout
, "x11-req");
6925 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6926 ssh2_pkt_addbool(s
->pktout
, 0); /* many connections */
6927 ssh2_pkt_addstring(s
->pktout
, proto
);
6928 ssh2_pkt_addstring(s
->pktout
, data
);
6929 ssh2_pkt_adduint32(s
->pktout
, x11_get_screen_number(ssh
->cfg
.x11_display
));
6930 ssh2_pkt_send(ssh
, s
->pktout
);
6932 crWaitUntilV(pktin
);
6934 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6935 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6936 bombout(("Unexpected response to X11 forwarding request:"
6937 " packet type %d", pktin
->type
));
6940 logevent("X11 forwarding refused");
6942 logevent("X11 forwarding enabled");
6943 ssh
->X11_fwd_enabled
= TRUE
;
6948 * Enable port forwardings.
6950 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
6953 * Potentially enable agent forwarding.
6955 if (ssh
->mainchan
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
6956 logevent("Requesting OpenSSH-style agent forwarding");
6957 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6958 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6959 ssh2_pkt_addstring(s
->pktout
, "auth-agent-req@openssh.com");
6960 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6961 ssh2_pkt_send(ssh
, s
->pktout
);
6963 crWaitUntilV(pktin
);
6965 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6966 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6967 bombout(("Unexpected response to agent forwarding request:"
6968 " packet type %d", pktin
->type
));
6971 logevent("Agent forwarding refused");
6973 logevent("Agent forwarding enabled");
6974 ssh
->agentfwd_enabled
= TRUE
;
6979 * Now allocate a pty for the session.
6981 if (ssh
->mainchan
&& !ssh
->cfg
.nopty
) {
6982 /* Unpick the terminal-speed string. */
6983 /* XXX perhaps we should allow no speeds to be sent. */
6984 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
6985 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
6986 /* Build the pty request. */
6987 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6988 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
6989 ssh2_pkt_addstring(s
->pktout
, "pty-req");
6990 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6991 ssh2_pkt_addstring(s
->pktout
, ssh
->cfg
.termtype
);
6992 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_width
);
6993 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_height
);
6994 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel width */
6995 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel height */
6996 ssh2_pkt_addstring_start(s
->pktout
);
6997 ssh2_pkt_addbyte(s
->pktout
, 128); /* TTY_OP_ISPEED */
6998 ssh2_pkt_adduint32(s
->pktout
, ssh
->ispeed
);
6999 ssh2_pkt_addbyte(s
->pktout
, 129); /* TTY_OP_OSPEED */
7000 ssh2_pkt_adduint32(s
->pktout
, ssh
->ospeed
);
7001 ssh2_pkt_addstring_data(s
->pktout
, "\0", 1); /* TTY_OP_END */
7002 ssh2_pkt_send(ssh
, s
->pktout
);
7003 ssh
->state
= SSH_STATE_INTERMED
;
7005 crWaitUntilV(pktin
);
7007 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7008 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7009 bombout(("Unexpected response to pty request:"
7010 " packet type %d", pktin
->type
));
7013 c_write_str(ssh
, "Server refused to allocate pty\r\n");
7014 ssh
->editing
= ssh
->echoing
= 1;
7016 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
7017 ssh
->ospeed
, ssh
->ispeed
);
7020 ssh
->editing
= ssh
->echoing
= 1;
7024 * Send environment variables.
7026 * Simplest thing here is to send all the requests at once, and
7027 * then wait for a whole bunch of successes or failures.
7029 if (ssh
->mainchan
&& *ssh
->cfg
.environmt
) {
7030 char *e
= ssh
->cfg
.environmt
;
7031 char *var
, *varend
, *val
;
7037 while (*e
&& *e
!= '\t') e
++;
7039 if (*e
== '\t') e
++;
7044 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7045 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7046 ssh2_pkt_addstring(s
->pktout
, "env");
7047 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7048 ssh2_pkt_addstring_start(s
->pktout
);
7049 ssh2_pkt_addstring_data(s
->pktout
, var
, varend
-var
);
7050 ssh2_pkt_addstring(s
->pktout
, val
);
7051 ssh2_pkt_send(ssh
, s
->pktout
);
7056 logeventf(ssh
, "Sent %d environment variables", s
->num_env
);
7059 s
->env_left
= s
->num_env
;
7061 while (s
->env_left
> 0) {
7062 crWaitUntilV(pktin
);
7064 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7065 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7066 bombout(("Unexpected response to environment request:"
7067 " packet type %d", pktin
->type
));
7077 if (s
->env_ok
== s
->num_env
) {
7078 logevent("All environment variables successfully set");
7079 } else if (s
->env_ok
== 0) {
7080 logevent("All environment variables refused");
7081 c_write_str(ssh
, "Server refused to set environment variables\r\n");
7083 logeventf(ssh
, "%d environment variables refused",
7084 s
->num_env
- s
->env_ok
);
7085 c_write_str(ssh
, "Server refused to set all environment variables\r\n");
7090 * Start a shell or a remote command. We may have to attempt
7091 * this twice if the config data has provided a second choice
7094 if (ssh
->mainchan
) while (1) {
7098 if (ssh
->fallback_cmd
) {
7099 subsys
= ssh
->cfg
.ssh_subsys2
;
7100 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
7102 subsys
= ssh
->cfg
.ssh_subsys
;
7103 cmd
= ssh
->cfg
.remote_cmd_ptr
;
7106 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7107 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7109 ssh2_pkt_addstring(s
->pktout
, "subsystem");
7110 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7111 ssh2_pkt_addstring(s
->pktout
, cmd
);
7113 ssh2_pkt_addstring(s
->pktout
, "exec");
7114 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7115 ssh2_pkt_addstring(s
->pktout
, cmd
);
7117 ssh2_pkt_addstring(s
->pktout
, "shell");
7118 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7120 ssh2_pkt_send(ssh
, s
->pktout
);
7122 crWaitUntilV(pktin
);
7124 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7125 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7126 bombout(("Unexpected response to shell/command request:"
7127 " packet type %d", pktin
->type
));
7131 * We failed to start the command. If this is the
7132 * fallback command, we really are finished; if it's
7133 * not, and if the fallback command exists, try falling
7134 * back to it before complaining.
7136 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
7137 logevent("Primary command failed; attempting fallback");
7138 ssh
->fallback_cmd
= TRUE
;
7141 bombout(("Server refused to start a shell/command"));
7144 logevent("Started a shell/command");
7149 ssh
->state
= SSH_STATE_SESSION
;
7150 if (ssh
->size_needed
)
7151 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
7152 if (ssh
->eof_needed
)
7153 ssh_special(ssh
, TS_EOF
);
7159 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
7164 s
->try_send
= FALSE
;
7168 * _All_ the connection-layer packets we expect to
7169 * receive are now handled by the dispatch table.
7170 * Anything that reaches here must be bogus.
7173 bombout(("Strange packet received: type %d", pktin
->type
));
7175 } else if (ssh
->mainchan
) {
7177 * We have spare data. Add it to the channel buffer.
7179 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
7184 struct ssh_channel
*c
;
7186 * Try to send data on all channels if we can.
7188 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
7191 continue; /* don't send on closing channels */
7192 bufsize
= ssh2_try_send(c
);
7195 case CHAN_MAINSESSION
:
7196 /* stdin need not receive an unthrottle
7197 * notification since it will be polled */
7200 x11_unthrottle(c
->u
.x11
.s
);
7203 /* agent sockets are request/response and need no
7204 * buffer management */
7207 pfd_unthrottle(c
->u
.pfd
.s
);
7219 * Handlers for SSH2 messages that might arrive at any moment.
7221 void ssh2_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
7223 /* log reason code in disconnect message */
7225 int nowlen
, reason
, msglen
;
7227 reason
= ssh_pkt_getuint32(pktin
);
7228 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7230 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
7231 buf
= dupprintf("Received disconnect message (%s)",
7232 ssh2_disconnect_reasons
[reason
]);
7234 buf
= dupprintf("Received disconnect message (unknown"
7235 " type %d)", reason
);
7239 buf
= dupprintf("Disconnection message text: %n%.*s",
7240 &nowlen
, msglen
, msg
);
7242 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7244 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
7245 ssh2_disconnect_reasons
[reason
] : "unknown",
7250 void ssh2_msg_debug(Ssh ssh
, struct Packet
*pktin
)
7252 /* log the debug message */
7257 /* XXX maybe we should actually take notice of this */
7258 always_display
= ssh2_pkt_getbool(pktin
);
7259 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7261 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
7266 void ssh2_msg_something_unimplemented(Ssh ssh
, struct Packet
*pktin
)
7268 struct Packet
*pktout
;
7269 pktout
= ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
7270 ssh2_pkt_adduint32(pktout
, pktin
->sequence
);
7272 * UNIMPLEMENTED messages MUST appear in the same order as the
7273 * messages they respond to. Hence, never queue them.
7275 ssh2_pkt_send_noqueue(ssh
, pktout
);
7279 * Handle the top-level SSH2 protocol.
7281 static void ssh2_protocol_setup(Ssh ssh
)
7286 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7288 for (i
= 0; i
< 256; i
++)
7289 ssh
->packet_dispatch
[i
] = ssh2_msg_something_unimplemented
;
7292 * Any message we actually understand, we set to NULL so that
7293 * the coroutines will get it.
7295 ssh
->packet_dispatch
[SSH2_MSG_UNIMPLEMENTED
] = NULL
;
7296 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_REQUEST
] = NULL
;
7297 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_ACCEPT
] = NULL
;
7298 ssh
->packet_dispatch
[SSH2_MSG_KEXINIT
] = NULL
;
7299 ssh
->packet_dispatch
[SSH2_MSG_NEWKEYS
] = NULL
;
7300 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_INIT
] = NULL
;
7301 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_REPLY
] = NULL
;
7302 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7303 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7304 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_INIT
] = NULL
;
7305 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_REPLY
] = NULL
;
7306 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_REQUEST
] = NULL
;
7307 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_FAILURE
] = NULL
;
7308 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_SUCCESS
] = NULL
;
7309 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
7310 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_PK_OK
] = NULL
;
7311 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7312 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7313 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_INFO_RESPONSE
] = NULL
;
7314 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] = NULL
;
7315 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_SUCCESS
] = NULL
;
7316 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_FAILURE
] = NULL
;
7317 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] = NULL
;
7318 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] = NULL
;
7319 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] = NULL
;
7320 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] = NULL
;
7321 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] = NULL
;
7322 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] = NULL
;
7323 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = NULL
;
7324 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = NULL
;
7325 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] = NULL
;
7326 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_SUCCESS
] = NULL
;
7327 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_FAILURE
] = NULL
;
7330 * These special message types we install handlers for.
7332 ssh
->packet_dispatch
[SSH2_MSG_DISCONNECT
] = ssh2_msg_disconnect
;
7333 ssh
->packet_dispatch
[SSH2_MSG_IGNORE
] = ssh_msg_ignore
; /* shared with ssh1 */
7334 ssh
->packet_dispatch
[SSH2_MSG_DEBUG
] = ssh2_msg_debug
;
7337 static void ssh2_timer(void *ctx
, long now
)
7341 if (!ssh
->kex_in_progress
&& ssh
->cfg
.ssh_rekey_time
!= 0 &&
7342 now
- ssh
->next_rekey
>= 0) {
7343 do_ssh2_transport(ssh
, "timeout", -1, NULL
);
7347 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
7348 struct Packet
*pktin
)
7350 if (ssh
->state
== SSH_STATE_CLOSED
)
7354 ssh
->incoming_data_size
+= pktin
->encrypted_len
;
7355 if (!ssh
->kex_in_progress
&&
7356 ssh
->max_data_size
!= 0 &&
7357 ssh
->incoming_data_size
> ssh
->max_data_size
)
7358 do_ssh2_transport(ssh
, "too much data received", -1, NULL
);
7361 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
7362 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
7366 if (!ssh
->protocol_initial_phase_done
||
7367 (pktin
&& pktin
->type
>= 20 && pktin
->type
< 50)) {
7368 if (do_ssh2_transport(ssh
, in
, inlen
, pktin
) &&
7369 !ssh
->protocol_initial_phase_done
) {
7370 ssh
->protocol_initial_phase_done
= TRUE
;
7372 * Allow authconn to initialise itself.
7374 do_ssh2_authconn(ssh
, NULL
, 0, NULL
);
7377 do_ssh2_authconn(ssh
, in
, inlen
, pktin
);
7382 * Called to set up the connection.
7384 * Returns an error message, or NULL on success.
7386 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
7388 char *host
, int port
, char **realhost
, int nodelay
,
7394 ssh
= snew(struct ssh_tag
);
7395 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7396 ssh
->version
= 0; /* when not ready yet */
7399 ssh
->v1_cipher_ctx
= NULL
;
7400 ssh
->crcda_ctx
= NULL
;
7401 ssh
->cscipher
= NULL
;
7402 ssh
->cs_cipher_ctx
= NULL
;
7403 ssh
->sccipher
= NULL
;
7404 ssh
->sc_cipher_ctx
= NULL
;
7406 ssh
->cs_mac_ctx
= NULL
;
7408 ssh
->sc_mac_ctx
= NULL
;
7410 ssh
->cs_comp_ctx
= NULL
;
7412 ssh
->sc_comp_ctx
= NULL
;
7414 ssh
->kex_ctx
= NULL
;
7415 ssh
->hostkey
= NULL
;
7417 ssh
->close_expected
= FALSE
;
7418 ssh
->state
= SSH_STATE_PREPACKET
;
7419 ssh
->size_needed
= FALSE
;
7420 ssh
->eof_needed
= FALSE
;
7423 ssh
->deferred_send_data
= NULL
;
7424 ssh
->deferred_len
= 0;
7425 ssh
->deferred_size
= 0;
7426 ssh
->fallback_cmd
= 0;
7428 ssh
->x11auth
= NULL
;
7429 ssh
->v1_compressing
= FALSE
;
7430 ssh
->v2_outgoing_sequence
= 0;
7431 ssh
->ssh1_rdpkt_crstate
= 0;
7432 ssh
->ssh2_rdpkt_crstate
= 0;
7433 ssh
->do_ssh_init_crstate
= 0;
7434 ssh
->ssh_gotdata_crstate
= 0;
7435 ssh
->do_ssh1_connection_crstate
= 0;
7436 ssh
->do_ssh1_login_crstate
= 0;
7437 ssh
->do_ssh2_transport_crstate
= 0;
7438 ssh
->do_ssh2_authconn_crstate
= 0;
7439 ssh
->do_ssh_init_state
= NULL
;
7440 ssh
->do_ssh1_login_state
= NULL
;
7441 ssh
->do_ssh2_transport_state
= NULL
;
7442 ssh
->do_ssh2_authconn_state
= NULL
;
7443 ssh
->mainchan
= NULL
;
7444 ssh
->throttled_all
= 0;
7445 ssh
->v1_stdout_throttling
= 0;
7447 ssh
->queuelen
= ssh
->queuesize
= 0;
7448 ssh
->queueing
= FALSE
;
7449 ssh
->qhead
= ssh
->qtail
= NULL
;
7450 ssh
->deferred_rekey_reason
= NULL
;
7452 *backend_handle
= ssh
;
7455 if (crypto_startup() == 0)
7456 return "Microsoft high encryption pack not installed!";
7459 ssh
->frontend
= frontend_handle
;
7460 ssh
->term_width
= ssh
->cfg
.width
;
7461 ssh
->term_height
= ssh
->cfg
.height
;
7463 ssh
->channels
= NULL
;
7464 ssh
->rportfwds
= NULL
;
7465 ssh
->portfwds
= NULL
;
7470 ssh
->v1_throttle_count
= 0;
7471 ssh
->overall_bufsize
= 0;
7472 ssh
->fallback_cmd
= 0;
7474 ssh
->protocol
= NULL
;
7476 ssh
->protocol_initial_phase_done
= FALSE
;
7480 ssh
->incoming_data_size
= ssh
->outgoing_data_size
=
7481 ssh
->deferred_data_size
= 0L;
7482 ssh
->max_data_size
= parse_blocksize(ssh
->cfg
.ssh_rekey_data
);
7483 ssh
->kex_in_progress
= FALSE
;
7485 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
7494 static void ssh_free(void *handle
)
7496 Ssh ssh
= (Ssh
) handle
;
7497 struct ssh_channel
*c
;
7498 struct ssh_rportfwd
*pf
;
7500 if (ssh
->v1_cipher_ctx
)
7501 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
7502 if (ssh
->cs_cipher_ctx
)
7503 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
7504 if (ssh
->sc_cipher_ctx
)
7505 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
7506 if (ssh
->cs_mac_ctx
)
7507 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
7508 if (ssh
->sc_mac_ctx
)
7509 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
7510 if (ssh
->cs_comp_ctx
) {
7512 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
7514 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
7516 if (ssh
->sc_comp_ctx
) {
7518 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
7520 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
7523 dh_cleanup(ssh
->kex_ctx
);
7524 sfree(ssh
->savedhost
);
7526 while (ssh
->queuelen
-- > 0)
7527 ssh_free_packet(ssh
->queue
[ssh
->queuelen
]);
7530 while (ssh
->qhead
) {
7531 struct queued_handler
*qh
= ssh
->qhead
;
7532 ssh
->qhead
= qh
->next
;
7535 ssh
->qhead
= ssh
->qtail
= NULL
;
7537 if (ssh
->channels
) {
7538 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
7541 if (c
->u
.x11
.s
!= NULL
)
7542 x11_close(c
->u
.x11
.s
);
7545 if (c
->u
.pfd
.s
!= NULL
)
7546 pfd_close(c
->u
.pfd
.s
);
7551 freetree234(ssh
->channels
);
7552 ssh
->channels
= NULL
;
7555 if (ssh
->rportfwds
) {
7556 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
7558 freetree234(ssh
->rportfwds
);
7559 ssh
->rportfwds
= NULL
;
7561 sfree(ssh
->deferred_send_data
);
7563 x11_free_auth(ssh
->x11auth
);
7564 sfree(ssh
->do_ssh_init_state
);
7565 sfree(ssh
->do_ssh1_login_state
);
7566 sfree(ssh
->do_ssh2_transport_state
);
7567 sfree(ssh
->do_ssh2_authconn_state
);
7568 if (ssh
->crcda_ctx
) {
7569 crcda_free_context(ssh
->crcda_ctx
);
7570 ssh
->crcda_ctx
= NULL
;
7573 ssh_do_close(ssh
, TRUE
);
7574 expire_timer_context(ssh
);
7576 pinger_free(ssh
->pinger
);
7583 * Reconfigure the SSH backend.
7585 static void ssh_reconfig(void *handle
, Config
*cfg
)
7587 Ssh ssh
= (Ssh
) handle
;
7588 char *rekeying
= NULL
, rekey_mandatory
= FALSE
;
7589 unsigned long old_max_data_size
;
7591 pinger_reconfig(ssh
->pinger
, &ssh
->cfg
, cfg
);
7592 ssh_setup_portfwd(ssh
, cfg
);
7594 if (ssh
->cfg
.ssh_rekey_time
!= cfg
->ssh_rekey_time
&&
7595 cfg
->ssh_rekey_time
!= 0) {
7596 long new_next
= ssh
->last_rekey
+ cfg
->ssh_rekey_time
*60*TICKSPERSEC
;
7597 long now
= GETTICKCOUNT();
7599 if (new_next
- now
< 0) {
7600 rekeying
= "timeout shortened";
7602 ssh
->next_rekey
= schedule_timer(new_next
- now
, ssh2_timer
, ssh
);
7606 old_max_data_size
= ssh
->max_data_size
;
7607 ssh
->max_data_size
= parse_blocksize(cfg
->ssh_rekey_data
);
7608 if (old_max_data_size
!= ssh
->max_data_size
&&
7609 ssh
->max_data_size
!= 0) {
7610 if (ssh
->outgoing_data_size
> ssh
->max_data_size
||
7611 ssh
->incoming_data_size
> ssh
->max_data_size
)
7612 rekeying
= "data limit lowered";
7615 if (ssh
->cfg
.compression
!= cfg
->compression
) {
7616 rekeying
= "compression setting changed";
7617 rekey_mandatory
= TRUE
;
7620 if (ssh
->cfg
.ssh2_des_cbc
!= cfg
->ssh2_des_cbc
||
7621 memcmp(ssh
->cfg
.ssh_cipherlist
, cfg
->ssh_cipherlist
,
7622 sizeof(ssh
->cfg
.ssh_cipherlist
))) {
7623 rekeying
= "cipher settings changed";
7624 rekey_mandatory
= TRUE
;
7627 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7630 if (!ssh
->kex_in_progress
) {
7631 do_ssh2_transport(ssh
, rekeying
, -1, NULL
);
7632 } else if (rekey_mandatory
) {
7633 ssh
->deferred_rekey_reason
= rekeying
;
7639 * Called to send data down the Telnet connection.
7641 static int ssh_send(void *handle
, char *buf
, int len
)
7643 Ssh ssh
= (Ssh
) handle
;
7645 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7648 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
7650 return ssh_sendbuffer(ssh
);
7654 * Called to query the current amount of buffered stdin data.
7656 static int ssh_sendbuffer(void *handle
)
7658 Ssh ssh
= (Ssh
) handle
;
7661 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7665 * If the SSH socket itself has backed up, add the total backup
7666 * size on that to any individual buffer on the stdin channel.
7669 if (ssh
->throttled_all
)
7670 override_value
= ssh
->overall_bufsize
;
7672 if (ssh
->version
== 1) {
7673 return override_value
;
7674 } else if (ssh
->version
== 2) {
7675 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
7676 return override_value
;
7678 return (override_value
+
7679 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
7686 * Called to set the size of the window from SSH's POV.
7688 static void ssh_size(void *handle
, int width
, int height
)
7690 Ssh ssh
= (Ssh
) handle
;
7691 struct Packet
*pktout
;
7693 ssh
->term_width
= width
;
7694 ssh
->term_height
= height
;
7696 switch (ssh
->state
) {
7697 case SSH_STATE_BEFORE_SIZE
:
7698 case SSH_STATE_PREPACKET
:
7699 case SSH_STATE_CLOSED
:
7700 break; /* do nothing */
7701 case SSH_STATE_INTERMED
:
7702 ssh
->size_needed
= TRUE
; /* buffer for later */
7704 case SSH_STATE_SESSION
:
7705 if (!ssh
->cfg
.nopty
) {
7706 if (ssh
->version
== 1) {
7707 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
7708 PKT_INT
, ssh
->term_height
,
7709 PKT_INT
, ssh
->term_width
,
7710 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
7711 } else if (ssh
->mainchan
) {
7712 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7713 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7714 ssh2_pkt_addstring(pktout
, "window-change");
7715 ssh2_pkt_addbool(pktout
, 0);
7716 ssh2_pkt_adduint32(pktout
, ssh
->term_width
);
7717 ssh2_pkt_adduint32(pktout
, ssh
->term_height
);
7718 ssh2_pkt_adduint32(pktout
, 0);
7719 ssh2_pkt_adduint32(pktout
, 0);
7720 ssh2_pkt_send(ssh
, pktout
);
7728 * Return a list of the special codes that make sense in this
7731 static const struct telnet_special
*ssh_get_specials(void *handle
)
7733 static const struct telnet_special ssh1_ignore_special
[] = {
7734 {"IGNORE message", TS_NOP
}
7736 static const struct telnet_special ssh2_transport_specials
[] = {
7737 {"IGNORE message", TS_NOP
},
7738 {"Repeat key exchange", TS_REKEY
},
7740 static const struct telnet_special ssh2_session_specials
[] = {
7743 /* These are the signal names defined by draft-ietf-secsh-connect-23.
7744 * They include all the ISO C signals, but are a subset of the POSIX
7745 * required signals. */
7746 {"SIGINT (Interrupt)", TS_SIGINT
},
7747 {"SIGTERM (Terminate)", TS_SIGTERM
},
7748 {"SIGKILL (Kill)", TS_SIGKILL
},
7749 {"SIGQUIT (Quit)", TS_SIGQUIT
},
7750 {"SIGHUP (Hangup)", TS_SIGHUP
},
7751 {"More signals", TS_SUBMENU
},
7752 {"SIGABRT", TS_SIGABRT
}, {"SIGALRM", TS_SIGALRM
},
7753 {"SIGFPE", TS_SIGFPE
}, {"SIGILL", TS_SIGILL
},
7754 {"SIGPIPE", TS_SIGPIPE
}, {"SIGSEGV", TS_SIGSEGV
},
7755 {"SIGUSR1", TS_SIGUSR1
}, {"SIGUSR2", TS_SIGUSR2
},
7758 static const struct telnet_special specials_end
[] = {
7761 /* XXX review this length for any changes: */
7762 static struct telnet_special ssh_specials
[lenof(ssh2_transport_specials
) +
7763 lenof(ssh2_session_specials
) +
7764 lenof(specials_end
)];
7765 Ssh ssh
= (Ssh
) handle
;
7767 #define ADD_SPECIALS(name) \
7769 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7770 memcpy(&ssh_specials[i], name, sizeof name); \
7774 if (ssh
->version
== 1) {
7775 /* Don't bother offering IGNORE if we've decided the remote
7776 * won't cope with it, since we wouldn't bother sending it if
7778 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7779 ADD_SPECIALS(ssh1_ignore_special
);
7780 } else if (ssh
->version
== 2) {
7781 ADD_SPECIALS(ssh2_transport_specials
);
7783 ADD_SPECIALS(ssh2_session_specials
);
7784 } /* else we're not ready yet */
7787 ADD_SPECIALS(specials_end
);
7788 return ssh_specials
;
7796 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7797 * can send an EOF and collect resulting output (e.g. `plink
7800 static void ssh_special(void *handle
, Telnet_Special code
)
7802 Ssh ssh
= (Ssh
) handle
;
7803 struct Packet
*pktout
;
7805 if (code
== TS_EOF
) {
7806 if (ssh
->state
!= SSH_STATE_SESSION
) {
7808 * Buffer the EOF in case we are pre-SESSION, so we can
7809 * send it as soon as we reach SESSION.
7812 ssh
->eof_needed
= TRUE
;
7815 if (ssh
->version
== 1) {
7816 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
7817 } else if (ssh
->mainchan
) {
7818 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
7819 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7820 ssh2_pkt_send(ssh
, pktout
);
7822 logevent("Sent EOF message");
7823 } else if (code
== TS_PING
|| code
== TS_NOP
) {
7824 if (ssh
->state
== SSH_STATE_CLOSED
7825 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7826 if (ssh
->version
== 1) {
7827 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7828 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
7830 pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
7831 ssh2_pkt_addstring_start(pktout
);
7832 ssh2_pkt_send_noqueue(ssh
, pktout
);
7834 } else if (code
== TS_REKEY
) {
7835 if (!ssh
->kex_in_progress
&& ssh
->version
== 2) {
7836 do_ssh2_transport(ssh
, "at user request", -1, NULL
);
7838 } else if (code
== TS_BRK
) {
7839 if (ssh
->state
== SSH_STATE_CLOSED
7840 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7841 if (ssh
->version
== 1) {
7842 logevent("Unable to send BREAK signal in SSH1");
7843 } else if (ssh
->mainchan
) {
7844 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7845 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7846 ssh2_pkt_addstring(pktout
, "break");
7847 ssh2_pkt_addbool(pktout
, 0);
7848 ssh2_pkt_adduint32(pktout
, 0); /* default break length */
7849 ssh2_pkt_send(ssh
, pktout
);
7852 /* Is is a POSIX signal? */
7853 char *signame
= NULL
;
7854 if (code
== TS_SIGABRT
) signame
= "ABRT";
7855 if (code
== TS_SIGALRM
) signame
= "ALRM";
7856 if (code
== TS_SIGFPE
) signame
= "FPE";
7857 if (code
== TS_SIGHUP
) signame
= "HUP";
7858 if (code
== TS_SIGILL
) signame
= "ILL";
7859 if (code
== TS_SIGINT
) signame
= "INT";
7860 if (code
== TS_SIGKILL
) signame
= "KILL";
7861 if (code
== TS_SIGPIPE
) signame
= "PIPE";
7862 if (code
== TS_SIGQUIT
) signame
= "QUIT";
7863 if (code
== TS_SIGSEGV
) signame
= "SEGV";
7864 if (code
== TS_SIGTERM
) signame
= "TERM";
7865 if (code
== TS_SIGUSR1
) signame
= "USR1";
7866 if (code
== TS_SIGUSR2
) signame
= "USR2";
7867 /* The SSH-2 protocol does in principle support arbitrary named
7868 * signals, including signame@domain, but we don't support those. */
7870 /* It's a signal. */
7871 if (ssh
->version
== 2 && ssh
->mainchan
) {
7872 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7873 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7874 ssh2_pkt_addstring(pktout
, "signal");
7875 ssh2_pkt_addbool(pktout
, 0);
7876 ssh2_pkt_addstring(pktout
, signame
);
7877 ssh2_pkt_send(ssh
, pktout
);
7878 logeventf(ssh
, "Sent signal SIG%s", signame
);
7881 /* Never heard of it. Do nothing */
7886 void *new_sock_channel(void *handle
, Socket s
)
7888 Ssh ssh
= (Ssh
) handle
;
7889 struct ssh_channel
*c
;
7890 c
= snew(struct ssh_channel
);
7894 c
->remoteid
= -1; /* to be set when open confirmed */
7895 c
->localid
= alloc_channel_id(ssh
);
7897 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
7899 bufchain_init(&c
->v
.v2
.outbuffer
);
7900 add234(ssh
->channels
, c
);
7906 * This is called when stdout/stderr (the entity to which
7907 * from_backend sends data) manages to clear some backlog.
7909 static void ssh_unthrottle(void *handle
, int bufsize
)
7911 Ssh ssh
= (Ssh
) handle
;
7912 if (ssh
->version
== 1) {
7913 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
7914 ssh
->v1_stdout_throttling
= 0;
7915 ssh1_throttle(ssh
, -1);
7918 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
7919 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
7923 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
7925 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
7927 struct Packet
*pktout
;
7929 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
7931 if (ssh
->version
== 1) {
7932 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
7933 PKT_INT
, c
->localid
,
7936 /* PKT_STR, <org:orgport>, */
7939 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
7940 ssh2_pkt_addstring(pktout
, "direct-tcpip");
7941 ssh2_pkt_adduint32(pktout
, c
->localid
);
7942 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7943 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);/* our window size */
7944 ssh2_pkt_adduint32(pktout
, 0x4000UL
); /* our max pkt size */
7945 ssh2_pkt_addstring(pktout
, hostname
);
7946 ssh2_pkt_adduint32(pktout
, port
);
7948 * We make up values for the originator data; partly it's
7949 * too much hassle to keep track, and partly I'm not
7950 * convinced the server should be told details like that
7951 * about my local network configuration.
7953 ssh2_pkt_addstring(pktout
, "client-side-connection");
7954 ssh2_pkt_adduint32(pktout
, 0);
7955 ssh2_pkt_send(ssh
, pktout
);
7959 static Socket
ssh_socket(void *handle
)
7961 Ssh ssh
= (Ssh
) handle
;
7965 static int ssh_sendok(void *handle
)
7967 Ssh ssh
= (Ssh
) handle
;
7968 return ssh
->send_ok
;
7971 static int ssh_ldisc(void *handle
, int option
)
7973 Ssh ssh
= (Ssh
) handle
;
7974 if (option
== LD_ECHO
)
7975 return ssh
->echoing
;
7976 if (option
== LD_EDIT
)
7977 return ssh
->editing
;
7981 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
7983 Ssh ssh
= (Ssh
) handle
;
7987 static void ssh_provide_logctx(void *handle
, void *logctx
)
7989 Ssh ssh
= (Ssh
) handle
;
7990 ssh
->logctx
= logctx
;
7993 static int ssh_return_exitcode(void *handle
)
7995 Ssh ssh
= (Ssh
) handle
;
7999 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
8003 * cfg_info for SSH is the currently running version of the
8004 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
8006 static int ssh_cfg_info(void *handle
)
8008 Ssh ssh
= (Ssh
) handle
;
8009 return ssh
->version
;
8013 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
8014 * that fails. This variable is the means by which scp.c can reach
8015 * into the SSH code and find out which one it got.
8017 extern int ssh_fallback_cmd(void *handle
)
8019 Ssh ssh
= (Ssh
) handle
;
8020 return ssh
->fallback_cmd
;
8023 Backend ssh_backend
= {
8033 ssh_return_exitcode
,