18 #define logevent(s) { logevent(s); \
19 if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \
20 fprintf(stderr, "%s\n", s); }
22 #define bombout(msg) ( ssh_state = SSH_STATE_CLOSED, sk_close(s), \
23 s = NULL, connection_fatal msg )
25 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
26 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
27 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
28 #define SSH1_CMSG_USER 4 /* 0x4 */
29 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
30 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
31 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
32 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
33 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
34 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
35 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
36 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
37 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
38 #define SSH1_SMSG_FAILURE 15 /* 0xf */
39 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
40 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
41 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
42 #define SSH1_CMSG_EOF 19 /* 0x13 */
43 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
44 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
45 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
46 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
47 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
48 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
49 #define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
50 #define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
51 #define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
52 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
53 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
54 #define SSH1_MSG_IGNORE 32 /* 0x20 */
55 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
56 #define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
57 #define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
58 #define SSH1_MSG_DEBUG 36 /* 0x24 */
59 #define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
60 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
61 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
62 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
63 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
64 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
65 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
67 #define SSH1_AUTH_TIS 5 /* 0x5 */
68 #define SSH1_AUTH_CCARD 16 /* 0x10 */
70 #define SSH_AGENTC_REQUEST_RSA_IDENTITIES 1 /* 0x1 */
71 #define SSH_AGENT_RSA_IDENTITIES_ANSWER 2 /* 0x2 */
72 #define SSH_AGENTC_RSA_CHALLENGE 3 /* 0x3 */
73 #define SSH_AGENT_RSA_RESPONSE 4 /* 0x4 */
74 #define SSH_AGENT_FAILURE 5 /* 0x5 */
75 #define SSH_AGENT_SUCCESS 6 /* 0x6 */
76 #define SSH_AGENTC_ADD_RSA_IDENTITY 7 /* 0x7 */
77 #define SSH_AGENTC_REMOVE_RSA_IDENTITY 8 /* 0x8 */
79 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
80 #define SSH2_MSG_IGNORE 2 /* 0x2 */
81 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
82 #define SSH2_MSG_DEBUG 4 /* 0x4 */
83 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
84 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
85 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
86 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
87 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
88 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
89 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
90 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
91 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
92 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
93 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
94 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
95 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
96 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
97 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
98 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
99 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
100 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
101 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
102 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
103 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
104 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
105 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
106 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
107 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
108 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
110 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
111 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
112 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
113 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
114 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
115 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
116 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
117 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
118 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
119 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
120 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
122 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
123 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
124 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
125 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
127 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
129 #define GET_32BIT(cp) \
130 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
131 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
132 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
133 ((unsigned long)(unsigned char)(cp)[3]))
135 #define PUT_32BIT(cp, value) { \
136 (cp)[0] = (unsigned char)((value) >> 24); \
137 (cp)[1] = (unsigned char)((value) >> 16); \
138 (cp)[2] = (unsigned char)((value) >> 8); \
139 (cp)[3] = (unsigned char)(value); }
141 enum { PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
};
143 /* Coroutine mechanics for the sillier bits of the code */
144 #define crBegin1 static int crLine = 0;
145 #define crBegin2 switch(crLine) { case 0:;
146 #define crBegin crBegin1; crBegin2;
147 #define crFinish(z) } crLine = 0; return (z)
148 #define crFinishV } crLine = 0; return
149 #define crReturn(z) \
151 crLine=__LINE__; return (z); case __LINE__:;\
155 crLine=__LINE__; return; case __LINE__:;\
157 #define crStop(z) do{ crLine = 0; return (z); }while(0)
158 #define crStopV do{ crLine = 0; return; }while(0)
159 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
160 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
162 extern const struct ssh_cipher ssh_3des
;
163 extern const struct ssh_cipher ssh_3des_ssh2
;
164 extern const struct ssh_cipher ssh_des
;
165 extern const struct ssh_cipher ssh_blowfish_ssh1
;
166 extern const struct ssh_cipher ssh_blowfish_ssh2
;
168 extern char *x11_init (Socket
*, char *, void *);
169 extern void x11_close (Socket
);
170 extern void x11_send (Socket
, char *, int);
171 extern void x11_invent_auth(char *, int, char *, int);
174 * Ciphers for SSH2. We miss out single-DES because it isn't
175 * supported; also 3DES and Blowfish are both done differently from
176 * SSH1. (3DES uses outer chaining; Blowfish has the opposite
177 * endianness and different-sized keys.)
179 const static struct ssh_cipher
*ciphers
[] = { &ssh_blowfish_ssh2
, &ssh_3des_ssh2
};
181 extern const struct ssh_kex ssh_diffiehellman
;
182 const static struct ssh_kex
*kex_algs
[] = { &ssh_diffiehellman
};
184 extern const struct ssh_signkey ssh_dss
;
185 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_dss
};
187 extern const struct ssh_mac ssh_md5
, ssh_sha1
, ssh_sha1_buggy
;
189 static void nullmac_key(unsigned char *key
) { }
190 static void nullmac_generate(unsigned char *blk
, int len
, unsigned long seq
) { }
191 static int nullmac_verify(unsigned char *blk
, int len
, unsigned long seq
) { return 1; }
192 const static struct ssh_mac ssh_mac_none
= {
193 nullmac_key
, nullmac_key
, nullmac_generate
, nullmac_verify
, "none", 0
195 const static struct ssh_mac
*macs
[] = {
196 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
};
197 const static struct ssh_mac
*buggymacs
[] = {
198 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
};
200 static void ssh_comp_none_init(void) { }
201 static int ssh_comp_none_block(unsigned char *block
, int len
,
202 unsigned char **outblock
, int *outlen
) {
205 const static struct ssh_compress ssh_comp_none
= {
207 ssh_comp_none_init
, ssh_comp_none_block
,
208 ssh_comp_none_init
, ssh_comp_none_block
210 extern const struct ssh_compress ssh_zlib
;
211 const static struct ssh_compress
*compressions
[] = {
212 &ssh_zlib
, &ssh_comp_none
};
214 enum { /* channel types */
221 * 2-3-4 tree storing channels.
224 unsigned remoteid
, localid
;
227 struct ssh2_data_channel
{
228 unsigned char *outbuffer
;
229 unsigned outbuflen
, outbufsize
;
230 unsigned remwindow
, remmaxpkt
;
233 struct ssh_agent_channel
{
234 unsigned char *message
;
235 unsigned char msglen
[4];
236 int lensofar
, totallen
;
238 struct ssh_x11_channel
{
253 static SHA_State exhash
, exhashbase
;
255 static Socket s
= NULL
;
257 static unsigned char session_key
[32];
258 static int ssh1_compressing
;
259 static int ssh_agentfwd_enabled
;
260 static int ssh_X11_fwd_enabled
;
261 static const struct ssh_cipher
*cipher
= NULL
;
262 static const struct ssh_cipher
*cscipher
= NULL
;
263 static const struct ssh_cipher
*sccipher
= NULL
;
264 static const struct ssh_mac
*csmac
= NULL
;
265 static const struct ssh_mac
*scmac
= NULL
;
266 static const struct ssh_compress
*cscomp
= NULL
;
267 static const struct ssh_compress
*sccomp
= NULL
;
268 static const struct ssh_kex
*kex
= NULL
;
269 static const struct ssh_signkey
*hostkey
= NULL
;
270 int (*ssh_get_password
)(const char *prompt
, char *str
, int maxlen
) = NULL
;
272 static char *savedhost
;
273 static int savedport
;
274 static int ssh_send_ok
;
275 static int ssh_echoing
, ssh_editing
;
277 static tree234
*ssh_channels
; /* indexed by local id */
278 static struct ssh_channel
*mainchan
; /* primary session channel */
282 SSH_STATE_BEFORE_SIZE
,
286 } ssh_state
= SSH_STATE_PREPACKET
;
288 static int size_needed
= FALSE
, eof_needed
= FALSE
;
290 static struct Packet pktin
= { 0, 0, NULL
, NULL
, 0 };
291 static struct Packet pktout
= { 0, 0, NULL
, NULL
, 0 };
293 static int ssh_version
;
294 static void (*ssh_protocol
)(unsigned char *in
, int inlen
, int ispkt
);
295 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
);
296 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
);
297 static void ssh_size(void);
298 static void ssh_special (Telnet_Special
);
299 static void ssh2_try_send(struct ssh_channel
*c
);
300 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
302 static int (*s_rdpkt
)(unsigned char **data
, int *datalen
);
304 static struct rdpkt1_state_tag
{
305 long len
, pad
, biglen
, to_read
;
306 unsigned long realcrc
, gotcrc
;
312 static struct rdpkt2_state_tag
{
313 long len
, pad
, payload
, packetlen
, maclen
;
316 unsigned long incoming_sequence
;
319 static int ssh_channelcmp(void *av
, void *bv
) {
320 struct ssh_channel
*a
= (struct ssh_channel
*)av
;
321 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
322 if (a
->localid
< b
->localid
) return -1;
323 if (a
->localid
> b
->localid
) return +1;
326 static int ssh_channelfind(void *av
, void *bv
) {
327 unsigned *a
= (unsigned *)av
;
328 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
329 if (*a
< b
->localid
) return -1;
330 if (*a
> b
->localid
) return +1;
334 static void c_write (char *buf
, int len
) {
335 if ((flags
& FLAG_STDERR
)) {
337 for (i
= 0; i
< len
; i
++)
339 fputc(buf
[i
], stderr
);
342 from_backend(1, buf
, len
);
346 * Collect incoming data in the incoming packet buffer.
347 * Decipher and verify the packet when it is completely read.
348 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
349 * Update the *data and *datalen variables.
350 * Return the additional nr of bytes needed, or 0 when
351 * a complete packet is available.
353 static int ssh1_rdpkt(unsigned char **data
, int *datalen
)
355 struct rdpkt1_state_tag
*st
= &rdpkt1_state
;
364 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
365 while ((*datalen
) == 0)
367 st
->len
= (st
->len
<< 8) + **data
;
368 (*data
)++, (*datalen
)--;
372 if (st
->len
== 0x52656d6f) { /* "Remo"te server has closed ... */
373 st
->len
= 0x300; /* big enough to carry to end */
377 st
->pad
= 8 - (st
->len
% 8);
378 st
->biglen
= st
->len
+ st
->pad
;
379 pktin
.length
= st
->len
- 5;
381 if (pktin
.maxlen
< st
->biglen
) {
382 pktin
.maxlen
= st
->biglen
;
383 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->biglen
+APIEXTRA
) :
384 srealloc(pktin
.data
, st
->biglen
+APIEXTRA
));
386 fatalbox("Out of memory");
389 st
->to_read
= st
->biglen
;
391 while (st
->to_read
> 0) {
392 st
->chunk
= st
->to_read
;
393 while ((*datalen
) == 0)
394 crReturn(st
->to_read
);
395 if (st
->chunk
> (*datalen
))
396 st
->chunk
= (*datalen
);
397 memcpy(st
->p
, *data
, st
->chunk
);
399 *datalen
-= st
->chunk
;
401 st
->to_read
-= st
->chunk
;
405 cipher
->decrypt(pktin
.data
, st
->biglen
);
407 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
408 for (st
->i
= 0; st
->i
< st
->biglen
; st
->i
++)
409 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
413 st
->realcrc
= crc32(pktin
.data
, st
->biglen
-4);
414 st
->gotcrc
= GET_32BIT(pktin
.data
+st
->biglen
-4);
415 if (st
->gotcrc
!= st
->realcrc
) {
416 bombout(("Incorrect CRC received on packet"));
420 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
422 if (ssh1_compressing
) {
423 unsigned char *decompblk
;
427 debug(("Packet payload pre-decompression:\n"));
428 for (i
= -1; i
< pktin
.length
; i
++)
429 debug((" %02x", (unsigned char)pktin
.body
[i
]));
432 zlib_decompress_block(pktin
.body
-1, pktin
.length
+1,
433 &decompblk
, &decomplen
);
435 if (pktin
.maxlen
< st
->pad
+ decomplen
) {
436 pktin
.maxlen
= st
->pad
+ decomplen
;
437 pktin
.data
= srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
);
438 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
440 fatalbox("Out of memory");
443 memcpy(pktin
.body
-1, decompblk
, decomplen
);
445 pktin
.length
= decomplen
-1;
447 debug(("Packet payload post-decompression:\n"));
448 for (i
= -1; i
< pktin
.length
; i
++)
449 debug((" %02x", (unsigned char)pktin
.body
[i
]));
454 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
455 pktin
.type
== SSH1_SMSG_STDERR_DATA
||
456 pktin
.type
== SSH1_MSG_DEBUG
||
457 pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
458 pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
459 long strlen
= GET_32BIT(pktin
.body
);
460 if (strlen
+ 4 != pktin
.length
) {
461 bombout(("Received data packet with bogus string length"));
466 pktin
.type
= pktin
.body
[-1];
468 if (pktin
.type
== SSH1_MSG_DEBUG
) {
469 /* log debug message */
471 int strlen
= GET_32BIT(pktin
.body
);
472 strcpy(buf
, "Remote: ");
473 if (strlen
> 70) strlen
= 70;
474 memcpy(buf
+8, pktin
.body
+4, strlen
);
475 buf
[8+strlen
] = '\0';
478 } else if (pktin
.type
== SSH1_MSG_IGNORE
) {
486 static int ssh2_rdpkt(unsigned char **data
, int *datalen
)
488 struct rdpkt2_state_tag
*st
= &rdpkt2_state
;
496 st
->cipherblk
= sccipher
->blksize
;
499 if (st
->cipherblk
< 8)
502 if (pktin
.maxlen
< st
->cipherblk
) {
503 pktin
.maxlen
= st
->cipherblk
;
504 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->cipherblk
+APIEXTRA
) :
505 srealloc(pktin
.data
, st
->cipherblk
+APIEXTRA
));
507 fatalbox("Out of memory");
511 * Acquire and decrypt the first block of the packet. This will
512 * contain the length and padding details.
514 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
515 while ((*datalen
) == 0)
516 crReturn(st
->cipherblk
-st
->i
);
517 pktin
.data
[st
->i
] = *(*data
)++;
521 if (!memcmp(pktin
.data
, "Remo", 4)) {/* "Remo"te server has closed ... */
526 sccipher
->decrypt(pktin
.data
, st
->cipherblk
);
529 * Now get the length and padding figures.
531 st
->len
= GET_32BIT(pktin
.data
);
532 st
->pad
= pktin
.data
[4];
535 * This enables us to deduce the payload length.
537 st
->payload
= st
->len
- st
->pad
- 1;
539 pktin
.length
= st
->payload
+ 5;
542 * So now we can work out the total packet length.
544 st
->packetlen
= st
->len
+ 4;
545 st
->maclen
= scmac ? scmac
->len
: 0;
548 * Adjust memory allocation if packet is too big.
550 if (pktin
.maxlen
< st
->packetlen
+st
->maclen
) {
551 pktin
.maxlen
= st
->packetlen
+st
->maclen
;
552 pktin
.data
= (pktin
.data
== NULL ?
smalloc(pktin
.maxlen
+APIEXTRA
) :
553 srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
555 fatalbox("Out of memory");
559 * Read and decrypt the remainder of the packet.
561 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
; st
->i
++) {
562 while ((*datalen
) == 0)
563 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
564 pktin
.data
[st
->i
] = *(*data
)++;
567 /* Decrypt everything _except_ the MAC. */
569 sccipher
->decrypt(pktin
.data
+ st
->cipherblk
,
570 st
->packetlen
- st
->cipherblk
);
573 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
574 for (st
->i
= 0; st
->i
< st
->packetlen
; st
->i
++)
575 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
582 if (scmac
&& !scmac
->verify(pktin
.data
, st
->len
+4, st
->incoming_sequence
)) {
583 bombout(("Incorrect MAC received on packet"));
586 st
->incoming_sequence
++; /* whether or not we MACed */
589 * Decompress packet payload.
592 unsigned char *newpayload
;
594 if (sccomp
&& sccomp
->decompress(pktin
.data
+5, pktin
.length
-5,
595 &newpayload
, &newlen
)) {
596 if (pktin
.maxlen
< newlen
+5) {
597 pktin
.maxlen
= newlen
+5;
598 pktin
.data
= (pktin
.data
== NULL ?
smalloc(pktin
.maxlen
+APIEXTRA
) :
599 srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
601 fatalbox("Out of memory");
603 pktin
.length
= 5 + newlen
;
604 memcpy(pktin
.data
+5, newpayload
, newlen
);
606 debug(("Post-decompression payload:\r\n"));
607 for (st
->i
= 0; st
->i
< newlen
; st
->i
++)
608 debug((" %02x", (unsigned char)pktin
.data
[5+st
->i
]));
617 pktin
.type
= pktin
.data
[5];
619 if (pktin
.type
== SSH2_MSG_IGNORE
|| pktin
.type
== SSH2_MSG_DEBUG
)
620 goto next_packet
; /* FIXME: print DEBUG message */
625 static void ssh1_pktout_size(int len
) {
628 len
+= 5; /* type and CRC */
632 pktout
.length
= len
-5;
633 if (pktout
.maxlen
< biglen
) {
634 pktout
.maxlen
= biglen
;
636 /* Allocate enough buffer space for extra block
637 * for MS CryptEncrypt() */
638 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+12) :
639 srealloc(pktout
.data
, biglen
+12));
641 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+4) :
642 srealloc(pktout
.data
, biglen
+4));
645 fatalbox("Out of memory");
647 pktout
.body
= pktout
.data
+4+pad
+1;
650 static void s_wrpkt_start(int type
, int len
) {
651 ssh1_pktout_size(len
);
655 static void s_wrpkt(void) {
656 int pad
, len
, biglen
, i
;
659 pktout
.body
[-1] = pktout
.type
;
661 if (ssh1_compressing
) {
662 unsigned char *compblk
;
665 debug(("Packet payload pre-compression:\n"));
666 for (i
= -1; i
< pktout
.length
; i
++)
667 debug((" %02x", (unsigned char)pktout
.body
[i
]));
670 zlib_compress_block(pktout
.body
-1, pktout
.length
+1,
672 ssh1_pktout_size(complen
-1);
673 memcpy(pktout
.body
-1, compblk
, complen
);
676 debug(("Packet payload post-compression:\n"));
677 for (i
= -1; i
< pktout
.length
; i
++)
678 debug((" %02x", (unsigned char)pktout
.body
[i
]));
683 len
= pktout
.length
+ 5; /* type and CRC */
687 for (i
=0; i
<pad
; i
++)
688 pktout
.data
[i
+4] = random_byte();
689 crc
= crc32(pktout
.data
+4, biglen
-4);
690 PUT_32BIT(pktout
.data
+biglen
, crc
);
691 PUT_32BIT(pktout
.data
, len
);
694 debug(("Sending packet len=%d\r\n", biglen
+4));
695 for (i
= 0; i
< biglen
+4; i
++)
696 debug((" %02x", (unsigned char)pktout
.data
[i
]));
700 cipher
->encrypt(pktout
.data
+4, biglen
);
702 sk_write(s
, pktout
.data
, biglen
+4);
706 * Construct a packet with the specified contents and
707 * send it to the server.
709 static void send_packet(int pkttype
, ...)
712 unsigned char *p
, *argp
, argchar
;
713 unsigned long argint
;
714 int pktlen
, argtype
, arglen
;
718 va_start(args
, pkttype
);
719 while ((argtype
= va_arg(args
, int)) != PKT_END
) {
722 (void) va_arg(args
, int);
726 (void) va_arg(args
, char);
730 (void) va_arg(args
, unsigned char *);
731 arglen
= va_arg(args
, int);
735 argp
= va_arg(args
, unsigned char *);
736 arglen
= strlen(argp
);
737 pktlen
+= 4 + arglen
;
740 bn
= va_arg(args
, Bignum
);
741 pktlen
+= ssh1_bignum_length(bn
);
749 s_wrpkt_start(pkttype
, pktlen
);
752 va_start(args
, pkttype
);
753 while ((argtype
= va_arg(args
, int)) != PKT_END
) {
756 argint
= va_arg(args
, int);
757 PUT_32BIT(p
, argint
);
761 argchar
= va_arg(args
, unsigned char);
766 argp
= va_arg(args
, unsigned char *);
767 arglen
= va_arg(args
, int);
768 memcpy(p
, argp
, arglen
);
772 argp
= va_arg(args
, unsigned char *);
773 arglen
= strlen(argp
);
774 PUT_32BIT(p
, arglen
);
775 memcpy(p
+ 4, argp
, arglen
);
779 bn
= va_arg(args
, Bignum
);
780 p
+= ssh1_write_bignum(p
, bn
);
789 static int ssh_versioncmp(char *a
, char *b
) {
791 unsigned long av
, bv
;
793 av
= strtoul(a
, &ae
, 10);
794 bv
= strtoul(b
, &be
, 10);
795 if (av
!= bv
) return (av
< bv ?
-1 : +1);
796 if (*ae
== '.') ae
++;
797 if (*be
== '.') be
++;
798 av
= strtoul(ae
, &ae
, 10);
799 bv
= strtoul(be
, &be
, 10);
800 if (av
!= bv
) return (av
< bv ?
-1 : +1);
806 * Utility routine for putting an SSH-protocol `string' into a SHA
810 static void sha_string(SHA_State
*s
, void *str
, int len
) {
811 unsigned char lenblk
[4];
812 PUT_32BIT(lenblk
, len
);
813 SHA_Bytes(s
, lenblk
, 4);
814 SHA_Bytes(s
, str
, len
);
818 * SSH2 packet construction functions.
820 static void ssh2_pkt_ensure(int length
) {
821 if (pktout
.maxlen
< length
) {
822 pktout
.maxlen
= length
+ 256;
823 pktout
.data
= (pktout
.data
== NULL ?
smalloc(pktout
.maxlen
+APIEXTRA
) :
824 srealloc(pktout
.data
, pktout
.maxlen
+APIEXTRA
));
826 fatalbox("Out of memory");
829 static void ssh2_pkt_adddata(void *data
, int len
) {
830 pktout
.length
+= len
;
831 ssh2_pkt_ensure(pktout
.length
);
832 memcpy(pktout
.data
+pktout
.length
-len
, data
, len
);
834 static void ssh2_pkt_addbyte(unsigned char byte
) {
835 ssh2_pkt_adddata(&byte
, 1);
837 static void ssh2_pkt_init(int pkt_type
) {
839 ssh2_pkt_addbyte((unsigned char)pkt_type
);
841 static void ssh2_pkt_addbool(unsigned char value
) {
842 ssh2_pkt_adddata(&value
, 1);
844 static void ssh2_pkt_adduint32(unsigned long value
) {
847 ssh2_pkt_adddata(x
, 4);
849 static void ssh2_pkt_addstring_start(void) {
850 ssh2_pkt_adduint32(0);
851 pktout
.savedpos
= pktout
.length
;
853 static void ssh2_pkt_addstring_str(char *data
) {
854 ssh2_pkt_adddata(data
, strlen(data
));
855 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
856 pktout
.length
- pktout
.savedpos
);
858 static void ssh2_pkt_addstring_data(char *data
, int len
) {
859 ssh2_pkt_adddata(data
, len
);
860 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
861 pktout
.length
- pktout
.savedpos
);
863 static void ssh2_pkt_addstring(char *data
) {
864 ssh2_pkt_addstring_start();
865 ssh2_pkt_addstring_str(data
);
867 static char *ssh2_mpint_fmt(Bignum b
, int *len
) {
870 p
= smalloc(n
* 2 + 1);
872 fatalbox("out of memory");
874 for (i
= 0; i
< n
; i
++) {
875 p
[i
*2+1] = (b
[n
-i
] >> 8) & 0xFF;
876 p
[i
*2+2] = (b
[n
-i
] ) & 0xFF;
879 while (p
[i
] == 0 && (p
[i
+1] & 0x80) == 0)
881 memmove(p
, p
+i
, n
*2+1-i
);
885 static void ssh2_pkt_addmp(Bignum b
) {
888 p
= ssh2_mpint_fmt(b
, &len
);
889 ssh2_pkt_addstring_start();
890 ssh2_pkt_addstring_data(p
, len
);
893 static void ssh2_pkt_send(void) {
894 int cipherblk
, maclen
, padding
, i
;
895 static unsigned long outgoing_sequence
= 0;
898 * Compress packet payload.
901 debug(("Pre-compression payload:\r\n"));
902 for (i
= 5; i
< pktout
.length
; i
++)
903 debug((" %02x", (unsigned char)pktout
.data
[i
]));
907 unsigned char *newpayload
;
909 if (cscomp
&& cscomp
->compress(pktout
.data
+5, pktout
.length
-5,
910 &newpayload
, &newlen
)) {
912 ssh2_pkt_adddata(newpayload
, newlen
);
918 * Add padding. At least four bytes, and must also bring total
919 * length (minus MAC) up to a multiple of the block size.
921 cipherblk
= cipher ? cipher
->blksize
: 8; /* block size */
922 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
924 padding
+= (cipherblk
- (pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
925 maclen
= csmac ? csmac
->len
: 0;
926 ssh2_pkt_ensure(pktout
.length
+ padding
+ maclen
);
927 pktout
.data
[4] = padding
;
928 for (i
= 0; i
< padding
; i
++)
929 pktout
.data
[pktout
.length
+ i
] = random_byte();
930 PUT_32BIT(pktout
.data
, pktout
.length
+ padding
- 4);
932 csmac
->generate(pktout
.data
, pktout
.length
+ padding
,
934 outgoing_sequence
++; /* whether or not we MACed */
937 debug(("Sending packet len=%d\r\n", pktout
.length
+padding
));
938 for (i
= 0; i
< pktout
.length
+padding
; i
++)
939 debug((" %02x", (unsigned char)pktout
.data
[i
]));
944 cscipher
->encrypt(pktout
.data
, pktout
.length
+ padding
);
946 sk_write(s
, pktout
.data
, pktout
.length
+ padding
+ maclen
);
950 void bndebug(char *string
, Bignum b
) {
953 p
= ssh2_mpint_fmt(b
, &len
);
954 debug(("%s", string
));
955 for (i
= 0; i
< len
; i
++)
956 debug((" %02x", p
[i
]));
962 static void sha_mpint(SHA_State
*s
, Bignum b
) {
965 p
= ssh2_mpint_fmt(b
, &len
);
966 sha_string(s
, p
, len
);
971 * SSH2 packet decode functions.
973 static unsigned long ssh2_pkt_getuint32(void) {
975 if (pktin
.length
- pktin
.savedpos
< 4)
976 return 0; /* arrgh, no way to decline (FIXME?) */
977 value
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
981 static void ssh2_pkt_getstring(char **p
, int *length
) {
983 if (pktin
.length
- pktin
.savedpos
< 4)
985 *length
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
987 if (pktin
.length
- pktin
.savedpos
< *length
)
989 *p
= pktin
.data
+pktin
.savedpos
;
990 pktin
.savedpos
+= *length
;
992 static Bignum
ssh2_pkt_getmp(void) {
997 ssh2_pkt_getstring(&p
, &length
);
1001 bombout(("internal error: Can't handle negative mpints"));
1004 b
= newbn((length
+1)/2);
1005 for (i
= 0; i
< length
; i
++) {
1008 b
[j
/2+1] |= ((unsigned char)p
[i
]) << 8;
1010 b
[j
/2+1] |= ((unsigned char)p
[i
]);
1012 while (b
[0] > 1 && b
[b
[0]] == 0) b
[0]--;
1016 static int do_ssh_init(unsigned char c
) {
1018 static char version
[10];
1019 static char vstring
[80];
1020 static char vlog
[sizeof(vstring
)+20];
1025 /* Search for the string "SSH-" in the input. */
1028 static const int transS
[] = { 1, 2, 2, 1 };
1029 static const int transH
[] = { 0, 0, 3, 0 };
1030 static const int transminus
[] = { 0, 0, 0, -1 };
1031 if (c
== 'S') i
= transS
[i
];
1032 else if (c
== 'H') i
= transH
[i
];
1033 else if (c
== '-') i
= transminus
[i
];
1037 crReturn(1); /* get another character */
1040 strcpy(vstring
, "SSH-");
1044 crReturn(1); /* get another char */
1045 if (vsp
< vstring
+sizeof(vstring
)-1)
1051 } else if (i
< sizeof(version
)-1)
1058 ssh_agentfwd_enabled
= FALSE
;
1059 rdpkt2_state
.incoming_sequence
= 0;
1062 sprintf(vlog
, "Server version: %s", vstring
);
1063 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1067 * Server version "1.99" means we can choose whether we use v1
1068 * or v2 protocol. Choice is based on cfg.sshprot.
1070 if (ssh_versioncmp(version
, cfg
.sshprot
== 1 ?
"2.0" : "1.99") >= 0) {
1072 * This is a v2 server. Begin v2 protocol.
1074 char *verstring
= "SSH-2.0-PuTTY";
1075 SHA_Init(&exhashbase
);
1077 * Hash our version string and their version string.
1079 sha_string(&exhashbase
, verstring
, strlen(verstring
));
1080 sha_string(&exhashbase
, vstring
, strcspn(vstring
, "\r\n"));
1081 sprintf(vstring
, "%s\n", verstring
);
1082 sprintf(vlog
, "We claim version: %s", verstring
);
1084 logevent("Using SSH protocol version 2");
1085 sk_write(s
, vstring
, strlen(vstring
));
1086 ssh_protocol
= ssh2_protocol
;
1088 s_rdpkt
= ssh2_rdpkt
;
1091 * This is a v1 server. Begin v1 protocol.
1093 sprintf(vstring
, "SSH-%s-PuTTY\n",
1094 (ssh_versioncmp(version
, "1.5") <= 0 ? version
: "1.5"));
1095 sprintf(vlog
, "We claim version: %s", vstring
);
1096 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1098 logevent("Using SSH protocol version 1");
1099 sk_write(s
, vstring
, strlen(vstring
));
1100 ssh_protocol
= ssh1_protocol
;
1102 s_rdpkt
= ssh1_rdpkt
;
1104 ssh_state
= SSH_STATE_BEFORE_SIZE
;
1109 static void ssh_gotdata(unsigned char *data
, int datalen
)
1114 * To begin with, feed the characters one by one to the
1115 * protocol initialisation / selection function do_ssh_init().
1116 * When that returns 0, we're done with the initial greeting
1117 * exchange and can move on to packet discipline.
1122 crReturnV
; /* more data please */
1123 ret
= do_ssh_init(*data
);
1130 * We emerge from that loop when the initial negotiation is
1131 * over and we have selected an s_rdpkt function. Now pass
1132 * everything to s_rdpkt, and then pass the resulting packets
1133 * to the proper protocol handler.
1138 while (datalen
> 0) {
1139 if ( s_rdpkt(&data
, &datalen
) == 0 ) {
1140 ssh_protocol(NULL
, 0, 1);
1141 if (ssh_state
== SSH_STATE_CLOSED
) {
1151 static int ssh_receive(Socket skt
, int urgent
, char *data
, int len
) {
1153 /* A socket error has occurred. */
1154 connection_fatal(data
);
1158 /* Connection has closed. */
1159 ssh_state
= SSH_STATE_CLOSED
;
1164 ssh_gotdata (data
, len
);
1165 if (ssh_state
== SSH_STATE_CLOSED
) {
1176 * Connect to specified host and port.
1177 * Returns an error message, or NULL on success.
1178 * Also places the canonical host name into `realhost'.
1180 static char *connect_to_host(char *host
, int port
, char **realhost
)
1189 savedhost
= smalloc(1+strlen(host
));
1191 fatalbox("Out of memory");
1192 strcpy(savedhost
, host
);
1195 port
= 22; /* default ssh port */
1208 addr
= sk_namelookup(host
, realhost
);
1209 if ( (err
= sk_addr_error(addr
)) )
1219 s
= sk_new(addr
, port
, 0, ssh_receive
);
1220 if ( (err
= sk_socket_error(s
)) )
1224 sk_write(s
, "connect ", 8);
1225 sk_write(s
, FWhost
, strlen(FWhost
));
1228 sprintf(buf
, " %d\n", FWport
);
1229 sk_write(s
, buf
, strlen(buf
));
1237 * Handle the key exchange and user authentication phases.
1239 static int do_ssh1_login(unsigned char *in
, int inlen
, int ispkt
)
1242 unsigned char *rsabuf
, *keystr1
, *keystr2
;
1243 unsigned char cookie
[8];
1244 struct RSAKey servkey
, hostkey
;
1245 struct MD5Context md5c
;
1246 static unsigned long supported_ciphers_mask
, supported_auths_mask
;
1247 static int tried_publickey
;
1248 static unsigned char session_id
[16];
1250 static char username
[100];
1254 if (!ispkt
) crWaitUntil(ispkt
);
1256 if (pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
1257 bombout(("Public key packet not received"));
1261 logevent("Received public keys");
1263 memcpy(cookie
, pktin
.body
, 8);
1265 i
= makekey(pktin
.body
+8, &servkey
, &keystr1
, 0);
1266 j
= makekey(pktin
.body
+8+i
, &hostkey
, &keystr2
, 0);
1269 * Log the host key fingerprint.
1273 logevent("Host key fingerprint is:");
1274 strcpy(logmsg
, " ");
1275 hostkey
.comment
= NULL
;
1276 rsa_fingerprint(logmsg
+strlen(logmsg
), sizeof(logmsg
)-strlen(logmsg
),
1281 supported_ciphers_mask
= GET_32BIT(pktin
.body
+12+i
+j
);
1282 supported_auths_mask
= GET_32BIT(pktin
.body
+16+i
+j
);
1285 MD5Update(&md5c
, keystr2
, hostkey
.bytes
);
1286 MD5Update(&md5c
, keystr1
, servkey
.bytes
);
1287 MD5Update(&md5c
, pktin
.body
, 8);
1288 MD5Final(session_id
, &md5c
);
1290 for (i
=0; i
<32; i
++)
1291 session_key
[i
] = random_byte();
1293 len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
1295 rsabuf
= smalloc(len
);
1297 fatalbox("Out of memory");
1300 * Verify the host key.
1304 * First format the key into a string.
1306 int len
= rsastr_len(&hostkey
);
1307 char fingerprint
[100];
1308 char *keystr
= smalloc(len
);
1310 fatalbox("Out of memory");
1311 rsastr_fmt(keystr
, &hostkey
);
1312 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
1313 verify_ssh_host_key(savedhost
, savedport
, "rsa", keystr
, fingerprint
);
1317 for (i
=0; i
<32; i
++) {
1318 rsabuf
[i
] = session_key
[i
];
1320 rsabuf
[i
] ^= session_id
[i
];
1323 if (hostkey
.bytes
> servkey
.bytes
) {
1324 rsaencrypt(rsabuf
, 32, &servkey
);
1325 rsaencrypt(rsabuf
, servkey
.bytes
, &hostkey
);
1327 rsaencrypt(rsabuf
, 32, &hostkey
);
1328 rsaencrypt(rsabuf
, hostkey
.bytes
, &servkey
);
1331 logevent("Encrypted session key");
1333 cipher_type
= cfg
.cipher
== CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH
:
1334 cfg
.cipher
== CIPHER_DES ? SSH_CIPHER_DES
:
1336 if ((supported_ciphers_mask
& (1 << cipher_type
)) == 0) {
1337 c_write("Selected cipher not supported, falling back to 3DES\r\n", 53);
1338 cipher_type
= SSH_CIPHER_3DES
;
1340 switch (cipher_type
) {
1341 case SSH_CIPHER_3DES
: logevent("Using 3DES encryption"); break;
1342 case SSH_CIPHER_DES
: logevent("Using single-DES encryption"); break;
1343 case SSH_CIPHER_BLOWFISH
: logevent("Using Blowfish encryption"); break;
1346 send_packet(SSH1_CMSG_SESSION_KEY
,
1347 PKT_CHAR
, cipher_type
,
1348 PKT_DATA
, cookie
, 8,
1349 PKT_CHAR
, (len
*8) >> 8, PKT_CHAR
, (len
*8) & 0xFF,
1350 PKT_DATA
, rsabuf
, len
,
1354 logevent("Trying to enable encryption...");
1358 cipher
= cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
1359 cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
1361 cipher
->sesskey(session_key
);
1365 if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1366 bombout(("Encryption not successfully enabled"));
1370 logevent("Successfully started encryption");
1376 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
1377 c_write("login as: ", 10);
1380 crWaitUntil(!ispkt
);
1381 while (inlen
--) switch (c
= *in
++) {
1388 c_write("\b \b", 3);
1394 c_write("\b \b", 3);
1403 if (((c
>= ' ' && c
<= '~') ||
1404 ((unsigned char)c
>= 160)) && pos
< 40) {
1405 username
[pos
++] = c
;
1412 username
[strcspn(username
, "\n\r")] = '\0';
1414 strncpy(username
, cfg
.username
, 99);
1415 username
[99] = '\0';
1418 send_packet(SSH1_CMSG_USER
, PKT_STR
, username
, PKT_END
);
1420 char userlog
[22+sizeof(username
)];
1421 sprintf(userlog
, "Sent username \"%s\"", username
);
1423 if (flags
& FLAG_INTERACTIVE
&&
1424 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
1425 strcat(userlog
, "\r\n");
1426 c_write(userlog
, strlen(userlog
));
1433 tried_publickey
= 0;
1435 while (pktin
.type
== SSH1_SMSG_FAILURE
) {
1436 static char password
[100];
1437 static char prompt
[200];
1440 static int pwpkt_type
;
1442 * Show password prompt, having first obtained it via a TIS
1443 * or CryptoCard exchange if we're doing TIS or CryptoCard
1446 pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
1447 if (agent_exists()) {
1449 * Attempt RSA authentication using Pageant.
1451 static unsigned char request
[5], *response
, *p
;
1452 static int responselen
;
1453 static int i
, nkeys
;
1454 static int authed
= FALSE
;
1457 logevent("Pageant is running. Requesting keys.");
1459 /* Request the keys held by the agent. */
1460 PUT_32BIT(request
, 1);
1461 request
[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES
;
1462 agent_query(request
, 5, &r
, &responselen
);
1463 response
= (unsigned char *)r
;
1466 nkeys
= GET_32BIT(p
); p
+= 4;
1467 { char buf
[64]; sprintf(buf
, "Pageant has %d keys", nkeys
);
1469 for (i
= 0; i
< nkeys
; i
++) {
1470 static struct RSAKey key
;
1471 static Bignum challenge
;
1472 static char *commentp
;
1473 static int commentlen
;
1475 { char buf
[64]; sprintf(buf
, "Trying Pageant key #%d", i
);
1478 p
+= ssh1_read_bignum(p
, &key
.exponent
);
1479 p
+= ssh1_read_bignum(p
, &key
.modulus
);
1480 commentlen
= GET_32BIT(p
); p
+= 4;
1481 commentp
= p
; p
+= commentlen
;
1482 send_packet(SSH1_CMSG_AUTH_RSA
,
1483 PKT_BIGNUM
, key
.modulus
, PKT_END
);
1485 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1486 logevent("Key refused");
1489 logevent("Received RSA challenge");
1490 ssh1_read_bignum(pktin
.body
, &challenge
);
1492 char *agentreq
, *q
, *ret
;
1494 len
= 1 + 4; /* message type, bit count */
1495 len
+= ssh1_bignum_length(key
.exponent
);
1496 len
+= ssh1_bignum_length(key
.modulus
);
1497 len
+= ssh1_bignum_length(challenge
);
1498 len
+= 16; /* session id */
1499 len
+= 4; /* response format */
1500 agentreq
= smalloc(4 + len
);
1501 PUT_32BIT(agentreq
, len
);
1503 *q
++ = SSH_AGENTC_RSA_CHALLENGE
;
1504 PUT_32BIT(q
, ssh1_bignum_bitcount(key
.modulus
));
1506 q
+= ssh1_write_bignum(q
, key
.exponent
);
1507 q
+= ssh1_write_bignum(q
, key
.modulus
);
1508 q
+= ssh1_write_bignum(q
, challenge
);
1509 memcpy(q
, session_id
, 16); q
+= 16;
1510 PUT_32BIT(q
, 1); /* response format */
1511 agent_query(agentreq
, len
+4, &ret
, &retlen
);
1514 if (ret
[4] == SSH_AGENT_RSA_RESPONSE
) {
1515 logevent("Sending Pageant's response");
1516 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1517 PKT_DATA
, ret
+5, 16, PKT_END
);
1520 if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
1521 logevent("Pageant's response accepted");
1522 if (flags
& FLAG_VERBOSE
) {
1523 c_write("Authenticated using RSA key \"",
1525 c_write(commentp
, commentlen
);
1526 c_write("\" from agent\r\n", 14);
1530 logevent("Pageant's response not accepted");
1532 logevent("Pageant failed to answer challenge");
1536 logevent("No reply received from Pageant");
1539 freebn(key
.exponent
);
1540 freebn(key
.modulus
);
1549 if (*cfg
.keyfile
&& !tried_publickey
)
1550 pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
1552 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1554 (supported_auths_mask
& (1<<SSH1_AUTH_TIS
))) {
1555 pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
1556 logevent("Requested TIS authentication");
1557 send_packet(SSH1_CMSG_AUTH_TIS
, PKT_END
);
1559 if (pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
1560 logevent("TIS authentication declined");
1561 if (flags
& FLAG_INTERACTIVE
)
1562 c_write("TIS authentication refused.\r\n", 29);
1564 int challengelen
= ((pktin
.body
[0] << 24) |
1565 (pktin
.body
[1] << 16) |
1566 (pktin
.body
[2] << 8) |
1568 logevent("Received TIS challenge");
1569 if (challengelen
> sizeof(prompt
)-1)
1570 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1571 memcpy(prompt
, pktin
.body
+4, challengelen
);
1572 prompt
[challengelen
] = '\0';
1575 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1577 (supported_auths_mask
& (1<<SSH1_AUTH_CCARD
))) {
1578 pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
1579 logevent("Requested CryptoCard authentication");
1580 send_packet(SSH1_CMSG_AUTH_CCARD
, PKT_END
);
1582 if (pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
1583 logevent("CryptoCard authentication declined");
1584 c_write("CryptoCard authentication refused.\r\n", 29);
1586 int challengelen
= ((pktin
.body
[0] << 24) |
1587 (pktin
.body
[1] << 16) |
1588 (pktin
.body
[2] << 8) |
1590 logevent("Received CryptoCard challenge");
1591 if (challengelen
> sizeof(prompt
)-1)
1592 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1593 memcpy(prompt
, pktin
.body
+4, challengelen
);
1594 strncpy(prompt
+ challengelen
, "\r\nResponse : ",
1595 sizeof(prompt
)-challengelen
);
1596 prompt
[sizeof(prompt
)-1] = '\0';
1599 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
1600 sprintf(prompt
, "%.90s@%.90s's password: ",
1601 username
, savedhost
);
1603 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1604 char *comment
= NULL
;
1605 if (flags
& FLAG_VERBOSE
)
1606 c_write("Trying public key authentication.\r\n", 35);
1607 if (!rsakey_encrypted(cfg
.keyfile
, &comment
)) {
1608 if (flags
& FLAG_VERBOSE
)
1609 c_write("No passphrase required.\r\n", 25);
1612 sprintf(prompt
, "Passphrase for key \"%.100s\": ", comment
);
1616 if (ssh_get_password
) {
1617 if (!ssh_get_password(prompt
, password
, sizeof(password
))) {
1619 * get_password failed to get a password (for
1620 * example because one was supplied on the command
1621 * line which has already failed to work).
1624 logevent("No more passwords to try");
1625 ssh_state
= SSH_STATE_CLOSED
;
1629 c_write(prompt
, strlen(prompt
));
1633 crWaitUntil(!ispkt
);
1634 while (inlen
--) switch (c
= *in
++) {
1651 if (((c
>= ' ' && c
<= '~') ||
1652 ((unsigned char)c
>= 160)) && pos
< sizeof(password
))
1653 password
[pos
++] = c
;
1661 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1663 * Try public key authentication with the specified
1666 static struct RSAKey pubkey
;
1667 static Bignum challenge
, response
;
1669 static unsigned char buffer
[32];
1671 tried_publickey
= 1;
1672 i
= loadrsakey(cfg
.keyfile
, &pubkey
, NULL
, password
);
1674 c_write("Couldn't load public key from ", 30);
1675 c_write(cfg
.keyfile
, strlen(cfg
.keyfile
));
1676 c_write(".\r\n", 3);
1677 continue; /* go and try password */
1680 c_write("Wrong passphrase.\r\n", 19);
1681 tried_publickey
= 0;
1682 continue; /* try again */
1686 * Send a public key attempt.
1688 send_packet(SSH1_CMSG_AUTH_RSA
,
1689 PKT_BIGNUM
, pubkey
.modulus
, PKT_END
);
1692 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1693 c_write("Server refused our public key.\r\n", 32);
1694 continue; /* go and try password */
1696 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1697 bombout(("Bizarre response to offer of public key"));
1700 ssh1_read_bignum(pktin
.body
, &challenge
);
1701 response
= rsadecrypt(challenge
, &pubkey
);
1702 freebn(pubkey
.private_exponent
); /* burn the evidence */
1704 for (i
= 0; i
< 32; i
+= 2) {
1705 buffer
[i
] = response
[16-i
/2] >> 8;
1706 buffer
[i
+1] = response
[16-i
/2] & 0xFF;
1710 MD5Update(&md5c
, buffer
, 32);
1711 MD5Update(&md5c
, session_id
, 16);
1712 MD5Final(buffer
, &md5c
);
1714 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1715 PKT_DATA
, buffer
, 16, PKT_END
);
1718 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1719 if (flags
& FLAG_VERBOSE
)
1720 c_write("Failed to authenticate with our public key.\r\n",
1722 continue; /* go and try password */
1723 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1724 bombout(("Bizarre response to RSA authentication response"));
1728 break; /* we're through! */
1730 send_packet(pwpkt_type
, PKT_STR
, password
, PKT_END
);
1732 logevent("Sent password");
1733 memset(password
, 0, strlen(password
));
1735 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1736 if (flags
& FLAG_VERBOSE
)
1737 c_write("Access denied\r\n", 15);
1738 logevent("Authentication refused");
1739 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
1740 logevent("Received disconnect request");
1741 ssh_state
= SSH_STATE_CLOSED
;
1743 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1744 bombout(("Strange packet received, type %d", pktin
.type
));
1749 logevent("Authentication successful");
1754 void sshfwd_close(struct ssh_channel
*c
) {
1756 if (ssh_version
== 1) {
1757 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
, PKT_END
);
1759 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
1760 ssh2_pkt_adduint32(c
->remoteid
);
1764 if (c
->type
== CHAN_X11
) {
1766 logevent("X11 connection terminated");
1771 void sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
) {
1772 if (ssh_version
== 1) {
1773 send_packet(SSH1_MSG_CHANNEL_DATA
,
1774 PKT_INT
, c
->remoteid
,
1779 ssh2_add_channel_data(c
, buf
, len
);
1784 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
) {
1789 while (!do_ssh1_login(in
, inlen
, ispkt
)) {
1792 if (ssh_state
== SSH_STATE_CLOSED
)
1795 if (cfg
.agentfwd
&& agent_exists()) {
1796 logevent("Requesting agent forwarding");
1797 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
1798 do { crReturnV
; } while (!ispkt
);
1799 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1800 bombout(("Protocol confusion"));
1802 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1803 logevent("Agent forwarding refused");
1805 logevent("Agent forwarding enabled");
1806 ssh_agentfwd_enabled
= TRUE
;
1810 if (cfg
.x11_forward
) {
1811 char proto
[20], data
[64];
1812 logevent("Requesting X11 forwarding");
1813 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
1814 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
1815 PKT_STR
, proto
, PKT_STR
, data
,
1818 do { crReturnV
; } while (!ispkt
);
1819 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1820 bombout(("Protocol confusion"));
1822 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1823 logevent("X11 forwarding refused");
1825 logevent("X11 forwarding enabled");
1826 ssh_X11_fwd_enabled
= TRUE
;
1831 send_packet(SSH1_CMSG_REQUEST_PTY
,
1832 PKT_STR
, cfg
.termtype
,
1833 PKT_INT
, rows
, PKT_INT
, cols
,
1834 PKT_INT
, 0, PKT_INT
, 0,
1837 ssh_state
= SSH_STATE_INTERMED
;
1838 do { crReturnV
; } while (!ispkt
);
1839 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1840 bombout(("Protocol confusion"));
1842 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1843 c_write("Server refused to allocate pty\r\n", 32);
1844 ssh_editing
= ssh_echoing
= 1;
1846 logevent("Allocated pty");
1848 ssh_editing
= ssh_echoing
= 1;
1851 if (cfg
.compression
) {
1852 send_packet(SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
1853 do { crReturnV
; } while (!ispkt
);
1854 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1855 bombout(("Protocol confusion"));
1857 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1858 c_write("Server refused to compress\r\n", 32);
1860 logevent("Started compression");
1861 ssh1_compressing
= TRUE
;
1862 zlib_compress_init();
1863 zlib_decompress_init();
1866 if (*cfg
.remote_cmd
)
1867 send_packet(SSH1_CMSG_EXEC_CMD
, PKT_STR
, cfg
.remote_cmd
, PKT_END
);
1869 send_packet(SSH1_CMSG_EXEC_SHELL
, PKT_END
);
1870 logevent("Started session");
1872 ssh_state
= SSH_STATE_SESSION
;
1876 ssh_special(TS_EOF
);
1878 ldisc_send(NULL
, 0); /* cause ldisc to notice changes */
1880 ssh_channels
= newtree234(ssh_channelcmp
);
1884 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
1885 pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
1886 long len
= GET_32BIT(pktin
.body
);
1887 from_backend(pktin
.type
== SSH1_SMSG_STDERR_DATA
,
1889 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
1890 ssh_state
= SSH_STATE_CLOSED
;
1891 logevent("Received disconnect request");
1893 } else if (pktin
.type
== SSH1_SMSG_X11_OPEN
) {
1894 /* Remote side is trying to open a channel to talk to our
1895 * X-Server. Give them back a local channel number. */
1897 struct ssh_channel
*c
, *d
;
1900 logevent("Received X11 connect request");
1901 /* Refuse if X11 forwarding is disabled. */
1902 if (!ssh_X11_fwd_enabled
) {
1903 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
1904 PKT_INT
, GET_32BIT(pktin
.body
),
1906 logevent("Rejected X11 connect request");
1908 c
= smalloc(sizeof(struct ssh_channel
));
1910 if ( x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
1911 logevent("opening X11 forward connection failed");
1913 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
1914 PKT_INT
, GET_32BIT(pktin
.body
),
1917 logevent("opening X11 forward connection succeeded");
1918 for (i
=1, d
= first234(ssh_channels
, &e
); d
; d
= next234(&e
)) {
1920 break; /* found a free number */
1923 c
->remoteid
= GET_32BIT(pktin
.body
);
1926 c
->type
= CHAN_X11
; /* identify channel type */
1927 add234(ssh_channels
, c
);
1928 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
1929 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
1931 logevent("Opened X11 forward channel");
1934 } else if (pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
1935 /* Remote side is trying to open a channel to talk to our
1936 * agent. Give them back a local channel number. */
1938 struct ssh_channel
*c
;
1941 /* Refuse if agent forwarding is disabled. */
1942 if (!ssh_agentfwd_enabled
) {
1943 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
1944 PKT_INT
, GET_32BIT(pktin
.body
),
1948 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
)) {
1950 break; /* found a free number */
1953 c
= smalloc(sizeof(struct ssh_channel
));
1954 c
->remoteid
= GET_32BIT(pktin
.body
);
1957 c
->type
= CHAN_AGENT
; /* identify channel type */
1958 c
->u
.a
.lensofar
= 0;
1959 add234(ssh_channels
, c
);
1960 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
1961 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
1964 } else if (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
1965 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
1966 /* Remote side closes a channel. */
1967 unsigned i
= GET_32BIT(pktin
.body
);
1968 struct ssh_channel
*c
;
1969 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
1972 closetype
= (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
1973 send_packet(pktin
.type
, PKT_INT
, c
->remoteid
, PKT_END
);
1974 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
1975 logevent("X11 connection closed");
1976 assert(c
->u
.x11
.s
!= NULL
);
1977 x11_close(c
->u
.x11
.s
);
1980 c
->closes
|= closetype
;
1981 if (c
->closes
== 3) {
1982 del234(ssh_channels
, c
);
1986 } else if (pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
1987 /* Data sent down one of our channels. */
1988 int i
= GET_32BIT(pktin
.body
);
1989 int len
= GET_32BIT(pktin
.body
+4);
1990 unsigned char *p
= pktin
.body
+8;
1991 struct ssh_channel
*c
;
1992 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
1996 x11_send(c
->u
.x11
.s
, p
, len
);
1999 /* Data for an agent message. Buffer it. */
2001 if (c
->u
.a
.lensofar
< 4) {
2002 int l
= min(4 - c
->u
.a
.lensofar
, len
);
2003 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
, l
);
2004 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
2006 if (c
->u
.a
.lensofar
== 4) {
2007 c
->u
.a
.totallen
= 4 + GET_32BIT(c
->u
.a
.msglen
);
2008 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
2009 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
2011 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
2012 int l
= min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
, len
);
2013 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
, l
);
2014 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
2016 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
2017 void *reply
, *sentreply
;
2019 agent_query(c
->u
.a
.message
, c
->u
.a
.totallen
,
2024 /* Fake SSH_AGENT_FAILURE. */
2025 sentreply
= "\0\0\0\1\5";
2028 send_packet(SSH1_MSG_CHANNEL_DATA
,
2029 PKT_INT
, c
->remoteid
,
2031 PKT_DATA
, sentreply
, replylen
,
2035 sfree(c
->u
.a
.message
);
2036 c
->u
.a
.lensofar
= 0;
2042 } else if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
2043 /* may be from EXEC_SHELL on some servers */
2044 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2045 /* may be from EXEC_SHELL on some servers
2046 * if no pty is available or in other odd cases. Ignore */
2047 } else if (pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
2048 send_packet(SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
2050 bombout(("Strange packet received: type %d", pktin
.type
));
2055 int len
= min(inlen
, 512);
2056 send_packet(SSH1_CMSG_STDIN_DATA
,
2057 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
2068 * Utility routine for decoding comma-separated strings in KEXINIT.
2070 static int in_commasep_string(char *needle
, char *haystack
, int haylen
) {
2071 int needlen
= strlen(needle
);
2074 * Is it at the start of the string?
2076 if (haylen
>= needlen
&& /* haystack is long enough */
2077 !memcmp(needle
, haystack
, needlen
) && /* initial match */
2078 (haylen
== needlen
|| haystack
[needlen
] == ',')
2079 /* either , or EOS follows */
2083 * If not, search for the next comma and resume after that.
2084 * If no comma found, terminate.
2086 while (haylen
> 0 && *haystack
!= ',')
2087 haylen
--, haystack
++;
2090 haylen
--, haystack
++; /* skip over comma itself */
2095 * SSH2 key creation method.
2097 static void ssh2_mkkey(Bignum K
, char *H
, char chr
, char *keyspace
) {
2099 /* First 20 bytes. */
2102 SHA_Bytes(&s
, H
, 20);
2103 SHA_Bytes(&s
, &chr
, 1);
2104 SHA_Bytes(&s
, H
, 20);
2105 SHA_Final(&s
, keyspace
);
2106 /* Next 20 bytes. */
2109 SHA_Bytes(&s
, H
, 20);
2110 SHA_Bytes(&s
, keyspace
, 20);
2111 SHA_Final(&s
, keyspace
+20);
2115 * Handle the SSH2 transport layer.
2117 static int do_ssh2_transport(unsigned char *in
, int inlen
, int ispkt
)
2121 static Bignum e
, f
, K
;
2122 static const struct ssh_mac
**maclist
;
2124 static const struct ssh_cipher
*cscipher_tobe
= NULL
;
2125 static const struct ssh_cipher
*sccipher_tobe
= NULL
;
2126 static const struct ssh_mac
*csmac_tobe
= NULL
;
2127 static const struct ssh_mac
*scmac_tobe
= NULL
;
2128 static const struct ssh_compress
*cscomp_tobe
= NULL
;
2129 static const struct ssh_compress
*sccomp_tobe
= NULL
;
2130 static char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
2131 static int hostkeylen
, siglen
;
2132 static void *hkey
; /* actual host key */
2133 static unsigned char exchange_hash
[20];
2134 static unsigned char keyspace
[40];
2135 static const struct ssh_cipher
*preferred_cipher
;
2136 static const struct ssh_compress
*preferred_comp
;
2137 static int first_kex
;
2144 * Set up the preferred cipher and compression.
2146 if (cfg
.cipher
== CIPHER_BLOWFISH
) {
2147 preferred_cipher
= &ssh_blowfish_ssh2
;
2148 } else if (cfg
.cipher
== CIPHER_DES
) {
2149 logevent("Single DES not supported in SSH2; using 3DES");
2150 preferred_cipher
= &ssh_3des_ssh2
;
2151 } else if (cfg
.cipher
== CIPHER_3DES
) {
2152 preferred_cipher
= &ssh_3des_ssh2
;
2154 /* Shouldn't happen, but we do want to initialise to _something_. */
2155 preferred_cipher
= &ssh_3des_ssh2
;
2157 if (cfg
.compression
)
2158 preferred_comp
= &ssh_zlib
;
2160 preferred_comp
= &ssh_comp_none
;
2163 * Be prepared to work around the buggy MAC problem.
2166 maclist
= buggymacs
, nmacs
= lenof(buggymacs
);
2168 maclist
= macs
, nmacs
= lenof(macs
);
2172 * Construct and send our key exchange packet.
2174 ssh2_pkt_init(SSH2_MSG_KEXINIT
);
2175 for (i
= 0; i
< 16; i
++)
2176 ssh2_pkt_addbyte((unsigned char)random_byte());
2177 /* List key exchange algorithms. */
2178 ssh2_pkt_addstring_start();
2179 for (i
= 0; i
< lenof(kex_algs
); i
++) {
2180 ssh2_pkt_addstring_str(kex_algs
[i
]->name
);
2181 if (i
< lenof(kex_algs
)-1)
2182 ssh2_pkt_addstring_str(",");
2184 /* List server host key algorithms. */
2185 ssh2_pkt_addstring_start();
2186 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
2187 ssh2_pkt_addstring_str(hostkey_algs
[i
]->name
);
2188 if (i
< lenof(hostkey_algs
)-1)
2189 ssh2_pkt_addstring_str(",");
2191 /* List client->server encryption algorithms. */
2192 ssh2_pkt_addstring_start();
2193 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2194 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2195 ssh2_pkt_addstring_str(c
->name
);
2196 if (i
< lenof(ciphers
))
2197 ssh2_pkt_addstring_str(",");
2199 /* List server->client encryption algorithms. */
2200 ssh2_pkt_addstring_start();
2201 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2202 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2203 ssh2_pkt_addstring_str(c
->name
);
2204 if (i
< lenof(ciphers
))
2205 ssh2_pkt_addstring_str(",");
2207 /* List client->server MAC algorithms. */
2208 ssh2_pkt_addstring_start();
2209 for (i
= 0; i
< nmacs
; i
++) {
2210 ssh2_pkt_addstring_str(maclist
[i
]->name
);
2212 ssh2_pkt_addstring_str(",");
2214 /* List server->client MAC algorithms. */
2215 ssh2_pkt_addstring_start();
2216 for (i
= 0; i
< nmacs
; i
++) {
2217 ssh2_pkt_addstring_str(maclist
[i
]->name
);
2219 ssh2_pkt_addstring_str(",");
2221 /* List client->server compression algorithms. */
2222 ssh2_pkt_addstring_start();
2223 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2224 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2225 ssh2_pkt_addstring_str(c
->name
);
2226 if (i
< lenof(compressions
))
2227 ssh2_pkt_addstring_str(",");
2229 /* List server->client compression algorithms. */
2230 ssh2_pkt_addstring_start();
2231 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2232 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2233 ssh2_pkt_addstring_str(c
->name
);
2234 if (i
< lenof(compressions
))
2235 ssh2_pkt_addstring_str(",");
2237 /* List client->server languages. Empty list. */
2238 ssh2_pkt_addstring_start();
2239 /* List server->client languages. Empty list. */
2240 ssh2_pkt_addstring_start();
2241 /* First KEX packet does _not_ follow, because we're not that brave. */
2242 ssh2_pkt_addbool(FALSE
);
2244 ssh2_pkt_adduint32(0);
2246 exhash
= exhashbase
;
2247 sha_string(&exhash
, pktout
.data
+5, pktout
.length
-5);
2251 if (!ispkt
) crWaitUntil(ispkt
);
2252 sha_string(&exhash
, pktin
.data
+5, pktin
.length
-5);
2255 * Now examine the other side's KEXINIT to see what we're up
2258 if (pktin
.type
!= SSH2_MSG_KEXINIT
) {
2259 bombout(("expected key exchange packet from server"));
2262 kex
= NULL
; hostkey
= NULL
; cscipher_tobe
= NULL
; sccipher_tobe
= NULL
;
2263 csmac_tobe
= NULL
; scmac_tobe
= NULL
; cscomp_tobe
= NULL
; sccomp_tobe
= NULL
;
2264 pktin
.savedpos
+= 16; /* skip garbage cookie */
2265 ssh2_pkt_getstring(&str
, &len
); /* key exchange algorithms */
2266 for (i
= 0; i
< lenof(kex_algs
); i
++) {
2267 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
2272 ssh2_pkt_getstring(&str
, &len
); /* host key algorithms */
2273 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
2274 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
2275 hostkey
= hostkey_algs
[i
];
2279 ssh2_pkt_getstring(&str
, &len
); /* client->server cipher */
2280 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2281 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2282 if (in_commasep_string(c
->name
, str
, len
)) {
2287 ssh2_pkt_getstring(&str
, &len
); /* server->client cipher */
2288 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2289 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2290 if (in_commasep_string(c
->name
, str
, len
)) {
2295 ssh2_pkt_getstring(&str
, &len
); /* client->server mac */
2296 for (i
= 0; i
< nmacs
; i
++) {
2297 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2298 csmac_tobe
= maclist
[i
];
2302 ssh2_pkt_getstring(&str
, &len
); /* server->client mac */
2303 for (i
= 0; i
< nmacs
; i
++) {
2304 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2305 scmac_tobe
= maclist
[i
];
2309 ssh2_pkt_getstring(&str
, &len
); /* client->server compression */
2310 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2311 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2312 if (in_commasep_string(c
->name
, str
, len
)) {
2317 ssh2_pkt_getstring(&str
, &len
); /* server->client compression */
2318 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2319 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2320 if (in_commasep_string(c
->name
, str
, len
)) {
2327 * Currently we only support Diffie-Hellman and DSS, so let's
2328 * bomb out if those aren't selected.
2330 if (kex
!= &ssh_diffiehellman
|| hostkey
!= &ssh_dss
) {
2331 bombout(("internal fault: chaos in SSH 2 transport layer"));
2336 * Now we begin the fun. Generate and send e for Diffie-Hellman.
2339 ssh2_pkt_init(SSH2_MSG_KEXDH_INIT
);
2344 if (pktin
.type
!= SSH2_MSG_KEXDH_REPLY
) {
2345 bombout(("expected key exchange packet from server"));
2348 ssh2_pkt_getstring(&hostkeydata
, &hostkeylen
);
2349 f
= ssh2_pkt_getmp();
2350 ssh2_pkt_getstring(&sigdata
, &siglen
);
2354 sha_string(&exhash
, hostkeydata
, hostkeylen
);
2355 sha_mpint(&exhash
, e
);
2356 sha_mpint(&exhash
, f
);
2357 sha_mpint(&exhash
, K
);
2358 SHA_Final(&exhash
, exchange_hash
);
2361 debug(("Exchange hash is:\r\n"));
2362 for (i
= 0; i
< 20; i
++)
2363 debug((" %02x", exchange_hash
[i
]));
2367 hkey
= hostkey
->newkey(hostkeydata
, hostkeylen
);
2368 if (!hostkey
->verifysig(hkey
, sigdata
, siglen
, exchange_hash
, 20)) {
2369 bombout(("Server failed host key check"));
2374 * Expect SSH2_MSG_NEWKEYS from server.
2377 if (pktin
.type
!= SSH2_MSG_NEWKEYS
) {
2378 bombout(("expected new-keys packet from server"));
2383 * Authenticate remote host: verify host key. (We've already
2384 * checked the signature of the exchange hash.)
2386 keystr
= hostkey
->fmtkey(hkey
);
2387 fingerprint
= hostkey
->fingerprint(hkey
);
2388 verify_ssh_host_key(savedhost
, savedport
, hostkey
->keytype
,
2389 keystr
, fingerprint
);
2390 logevent("Host key fingerprint is:");
2391 logevent(fingerprint
);
2394 hostkey
->freekey(hkey
);
2397 * Send SSH2_MSG_NEWKEYS.
2399 ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
2403 * Create and initialise session keys.
2405 cscipher
= cscipher_tobe
;
2406 sccipher
= sccipher_tobe
;
2409 cscomp
= cscomp_tobe
;
2410 sccomp
= sccomp_tobe
;
2411 cscomp
->compress_init();
2412 sccomp
->decompress_init();
2414 * Set IVs after keys.
2416 ssh2_mkkey(K
, exchange_hash
, 'C', keyspace
); cscipher
->setcskey(keyspace
);
2417 ssh2_mkkey(K
, exchange_hash
, 'D', keyspace
); sccipher
->setsckey(keyspace
);
2418 ssh2_mkkey(K
, exchange_hash
, 'A', keyspace
); cscipher
->setcsiv(keyspace
);
2419 ssh2_mkkey(K
, exchange_hash
, 'B', keyspace
); sccipher
->setsciv(keyspace
);
2420 ssh2_mkkey(K
, exchange_hash
, 'E', keyspace
); csmac
->setcskey(keyspace
);
2421 ssh2_mkkey(K
, exchange_hash
, 'F', keyspace
); scmac
->setsckey(keyspace
);
2424 * If this is the first key exchange phase, we must pass the
2425 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
2426 * wants to see it but because it will need time to initialise
2427 * itself before it sees an actual packet. In subsequent key
2428 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
2429 * it would only confuse the layer above.
2437 * Now we're encrypting. Begin returning 1 to the protocol main
2438 * function so that other things can run on top of the
2439 * transport. If we ever see a KEXINIT, we must go back to the
2444 } while (!(ispkt
&& pktin
.type
== SSH2_MSG_KEXINIT
));
2445 goto begin_key_exchange
;
2451 * Add data to an SSH2 channel output buffer.
2453 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
) {
2454 if (c
->v2
.outbufsize
<
2455 c
->v2
.outbuflen
+ len
) {
2457 c
->v2
.outbuflen
+ len
+ 1024;
2458 c
->v2
.outbuffer
= srealloc(c
->v2
.outbuffer
,
2461 memcpy(c
->v2
.outbuffer
+ c
->v2
.outbuflen
,
2463 c
->v2
.outbuflen
+= len
;
2467 * Attempt to send data on an SSH2 channel.
2469 static void ssh2_try_send(struct ssh_channel
*c
) {
2470 while (c
->v2
.remwindow
> 0 &&
2471 c
->v2
.outbuflen
> 0) {
2472 unsigned len
= c
->v2
.remwindow
;
2473 if (len
> c
->v2
.outbuflen
)
2474 len
= c
->v2
.outbuflen
;
2475 if (len
> c
->v2
.remmaxpkt
)
2476 len
= c
->v2
.remmaxpkt
;
2477 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
2478 ssh2_pkt_adduint32(c
->remoteid
);
2479 ssh2_pkt_addstring_start();
2480 ssh2_pkt_addstring_data(c
->v2
.outbuffer
, len
);
2482 c
->v2
.outbuflen
-= len
;
2483 memmove(c
->v2
.outbuffer
, c
->v2
.outbuffer
+len
,
2485 c
->v2
.remwindow
-= len
;
2490 * Handle the SSH2 userauth and connection layers.
2492 static void do_ssh2_authconn(unsigned char *in
, int inlen
, int ispkt
)
2494 static unsigned long remote_winsize
;
2495 static unsigned long remote_maxpkt
;
2500 * Request userauth protocol, and await a response to it.
2502 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
2503 ssh2_pkt_addstring("ssh-userauth");
2505 crWaitUntilV(ispkt
);
2506 if (pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
2507 bombout(("Server refused user authentication protocol"));
2512 * FIXME: currently we support only password authentication.
2513 * (This places us technically in violation of the SSH2 spec.
2514 * We must fix this.)
2518 * Get a username and a password.
2520 static char username
[100];
2521 static char password
[100];
2525 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
2526 c_write("login as: ", 10);
2529 crWaitUntilV(!ispkt
);
2530 while (inlen
--) switch (c
= *in
++) {
2537 c_write("\b \b", 3);
2543 c_write("\b \b", 3);
2552 if (((c
>= ' ' && c
<= '~') ||
2553 ((unsigned char)c
>= 160)) && pos
< 40) {
2554 username
[pos
++] = c
;
2561 username
[strcspn(username
, "\n\r")] = '\0';
2564 strncpy(username
, cfg
.username
, 99);
2565 username
[99] = '\0';
2566 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
2567 sprintf(stuff
, "Using username \"%s\".\r\n", username
);
2568 c_write(stuff
, strlen(stuff
));
2572 if (ssh_get_password
) {
2574 sprintf(prompt
, "%.90s@%.90s's password: ", username
, savedhost
);
2575 if (!ssh_get_password(prompt
, password
, sizeof(password
))) {
2577 * get_password failed to get a password (for
2578 * example because one was supplied on the command
2579 * line which has already failed to work).
2582 logevent("No more passwords to try");
2583 ssh_state
= SSH_STATE_CLOSED
;
2587 c_write("password: ", 10);
2592 crWaitUntilV(!ispkt
);
2593 while (inlen
--) switch (c
= *in
++) {
2610 if (((c
>= ' ' && c
<= '~') ||
2611 ((unsigned char)c
>= 160)) && pos
< 40)
2612 password
[pos
++] = c
;
2619 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
2620 ssh2_pkt_addstring(username
);
2621 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2622 ssh2_pkt_addstring("password");
2623 ssh2_pkt_addbool(FALSE
);
2624 ssh2_pkt_addstring(password
);
2627 crWaitUntilV(ispkt
);
2628 if (pktin
.type
!= SSH2_MSG_USERAUTH_SUCCESS
) {
2629 c_write("Access denied\r\n", 15);
2630 logevent("Authentication refused");
2636 * Now we're authenticated for the connection protocol. The
2637 * connection protocol will automatically have started at this
2638 * point; there's no need to send SERVICE_REQUEST.
2642 * So now create a channel with a session in it.
2644 mainchan
= smalloc(sizeof(struct ssh_channel
));
2645 mainchan
->localid
= 100; /* as good as any */
2646 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
2647 ssh2_pkt_addstring("session");
2648 ssh2_pkt_adduint32(mainchan
->localid
);
2649 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
2650 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
2652 crWaitUntilV(ispkt
);
2653 if (pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
2654 bombout(("Server refused to open a session"));
2656 /* FIXME: error data comes back in FAILURE packet */
2658 if (ssh2_pkt_getuint32() != mainchan
->localid
) {
2659 bombout(("Server's channel confirmation cited wrong channel"));
2662 mainchan
->remoteid
= ssh2_pkt_getuint32();
2663 mainchan
->type
= CHAN_MAINSESSION
;
2664 mainchan
->closes
= 0;
2665 mainchan
->v2
.remwindow
= ssh2_pkt_getuint32();
2666 mainchan
->v2
.remmaxpkt
= ssh2_pkt_getuint32();
2667 mainchan
->v2
.outbuffer
= NULL
;
2668 mainchan
->v2
.outbuflen
= mainchan
->v2
.outbufsize
= 0;
2669 ssh_channels
= newtree234(ssh_channelcmp
);
2670 add234(ssh_channels
, mainchan
);
2671 logevent("Opened channel for session");
2674 * Potentially enable X11 forwarding.
2676 if (cfg
.x11_forward
) {
2677 char proto
[20], data
[64];
2678 logevent("Requesting X11 forwarding");
2679 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
2680 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2681 ssh2_pkt_adduint32(mainchan
->remoteid
);
2682 ssh2_pkt_addstring("x11-req");
2683 ssh2_pkt_addbool(1); /* want reply */
2684 ssh2_pkt_addbool(0); /* many connections */
2685 ssh2_pkt_addstring(proto
);
2686 ssh2_pkt_addstring(data
);
2687 ssh2_pkt_adduint32(0); /* screen number */
2691 crWaitUntilV(ispkt
);
2692 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2693 unsigned i
= ssh2_pkt_getuint32();
2694 struct ssh_channel
*c
;
2695 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2697 continue; /* nonexistent channel */
2698 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2700 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2702 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2703 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2704 bombout(("Server got confused by X11 forwarding request"));
2707 logevent("X11 forwarding refused");
2709 logevent("X11 forwarding enabled");
2710 ssh_X11_fwd_enabled
= TRUE
;
2715 * Now allocate a pty for the session.
2718 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2719 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
2720 ssh2_pkt_addstring("pty-req");
2721 ssh2_pkt_addbool(1); /* want reply */
2722 ssh2_pkt_addstring(cfg
.termtype
);
2723 ssh2_pkt_adduint32(cols
);
2724 ssh2_pkt_adduint32(rows
);
2725 ssh2_pkt_adduint32(0); /* pixel width */
2726 ssh2_pkt_adduint32(0); /* pixel height */
2727 ssh2_pkt_addstring_start();
2728 ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
2730 ssh_state
= SSH_STATE_INTERMED
;
2733 crWaitUntilV(ispkt
);
2734 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2735 unsigned i
= ssh2_pkt_getuint32();
2736 struct ssh_channel
*c
;
2737 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2739 continue; /* nonexistent channel */
2740 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2742 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2744 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2745 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2746 bombout(("Server got confused by pty request"));
2749 c_write("Server refused to allocate pty\r\n", 32);
2750 ssh_editing
= ssh_echoing
= 1;
2752 logevent("Allocated pty");
2755 ssh_editing
= ssh_echoing
= 1;
2759 * Start a shell or a remote command.
2761 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2762 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
2763 if (*cfg
.remote_cmd
) {
2764 ssh2_pkt_addstring("exec");
2765 ssh2_pkt_addbool(1); /* want reply */
2766 ssh2_pkt_addstring(cfg
.remote_cmd
);
2768 ssh2_pkt_addstring("shell");
2769 ssh2_pkt_addbool(1); /* want reply */
2773 crWaitUntilV(ispkt
);
2774 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2775 unsigned i
= ssh2_pkt_getuint32();
2776 struct ssh_channel
*c
;
2777 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2779 continue; /* nonexistent channel */
2780 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2782 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2783 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2784 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2785 bombout(("Server got confused by shell/command request"));
2788 bombout(("Server refused to start a shell/command"));
2791 logevent("Started a shell/command");
2794 ssh_state
= SSH_STATE_SESSION
;
2798 ssh_special(TS_EOF
);
2803 ldisc_send(NULL
, 0); /* cause ldisc to notice changes */
2806 static int try_send
;
2810 if (pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
2811 pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
2814 unsigned i
= ssh2_pkt_getuint32();
2815 struct ssh_channel
*c
;
2816 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2818 continue; /* nonexistent channel */
2819 if (pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
2820 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR
)
2821 continue; /* extended but not stderr */
2822 ssh2_pkt_getstring(&data
, &length
);
2825 case CHAN_MAINSESSION
:
2826 from_backend(pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
,
2830 x11_send(c
->u
.x11
.s
, data
, length
);
2834 * Enlarge the window again at the remote
2835 * side, just in case it ever runs down and
2836 * they fail to send us any more data.
2838 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2839 ssh2_pkt_adduint32(c
->remoteid
);
2840 ssh2_pkt_adduint32(length
);
2843 } else if (pktin
.type
== SSH2_MSG_DISCONNECT
) {
2844 ssh_state
= SSH_STATE_CLOSED
;
2845 logevent("Received disconnect message");
2847 } else if (pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
2848 continue; /* exit status et al; ignore (FIXME?) */
2849 } else if (pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
2850 unsigned i
= ssh2_pkt_getuint32();
2851 struct ssh_channel
*c
;
2853 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2855 continue; /* nonexistent channel */
2857 if (c
->type
== CHAN_X11
) {
2859 * Remote EOF on an X11 channel means we should
2860 * wrap up and close the channel ourselves.
2862 x11_close(c
->u
.x11
.s
);
2865 } else if (pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
2866 unsigned i
= ssh2_pkt_getuint32();
2867 struct ssh_channel
*c
;
2870 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2872 continue; /* nonexistent channel */
2873 if (c
->closes
== 0) {
2874 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
2875 ssh2_pkt_adduint32(c
->remoteid
);
2878 /* Do pre-close processing on the channel. */
2880 case CHAN_MAINSESSION
:
2881 break; /* nothing to see here, move along */
2885 del234(ssh_channels
, c
);
2886 sfree(c
->v2
.outbuffer
);
2890 * See if that was the last channel left open.
2892 c
= first234(ssh_channels
, &e
);
2894 logevent("All channels closed. Disconnecting");
2895 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
2896 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
2897 ssh2_pkt_addstring("All open channels closed");
2898 ssh2_pkt_addstring("en"); /* language tag */
2900 ssh_state
= SSH_STATE_CLOSED
;
2903 continue; /* remote sends close; ignore (FIXME) */
2904 } else if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2905 unsigned i
= ssh2_pkt_getuint32();
2906 struct ssh_channel
*c
;
2907 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2909 continue; /* nonexistent channel */
2910 mainchan
->v2
.remwindow
+= ssh2_pkt_getuint32();
2912 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
2916 struct ssh_channel
*c
;
2917 ssh2_pkt_getstring(&type
, &typelen
);
2918 c
= smalloc(sizeof(struct ssh_channel
));
2920 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
2921 if (!ssh_X11_fwd_enabled
)
2922 error
= "X11 forwarding is not enabled";
2923 else if ( x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
2924 error
= "Unable to open an X11 connection";
2929 error
= "Unsupported channel type requested";
2932 c
->remoteid
= ssh2_pkt_getuint32();
2934 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
2935 ssh2_pkt_adduint32(c
->remoteid
);
2936 ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED
);
2937 ssh2_pkt_addstring(error
);
2938 ssh2_pkt_addstring("en"); /* language tag */
2942 struct ssh_channel
*d
;
2946 for (i
=1, d
= first234(ssh_channels
, &e
); d
;
2949 break; /* found a free number */
2954 c
->v2
.remwindow
= ssh2_pkt_getuint32();
2955 c
->v2
.remmaxpkt
= ssh2_pkt_getuint32();
2956 c
->v2
.outbuffer
= NULL
;
2957 c
->v2
.outbuflen
= c
->v2
.outbufsize
= 0;
2958 add234(ssh_channels
, c
);
2959 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
2960 ssh2_pkt_adduint32(c
->remoteid
);
2961 ssh2_pkt_adduint32(c
->localid
);
2962 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
2963 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
2967 bombout(("Strange packet received: type %d", pktin
.type
));
2972 * We have spare data. Add it to the channel buffer.
2974 ssh2_add_channel_data(mainchan
, in
, inlen
);
2979 struct ssh_channel
*c
;
2981 * Try to send data on all channels if we can.
2983 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
))
2992 * Handle the top-level SSH2 protocol.
2994 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
)
2996 if (do_ssh2_transport(in
, inlen
, ispkt
) == 0)
2998 do_ssh2_authconn(in
, inlen
, ispkt
);
3002 * Called to set up the connection.
3004 * Returns an error message, or NULL on success.
3006 static char *ssh_init (char *host
, int port
, char **realhost
) {
3010 if(crypto_startup() == 0)
3011 return "Microsoft high encryption pack not installed!";
3018 p
= connect_to_host(host
, port
, realhost
);
3026 * Called to send data down the Telnet connection.
3028 static void ssh_send (char *buf
, int len
) {
3029 if (s
== NULL
|| ssh_protocol
== NULL
)
3032 ssh_protocol(buf
, len
, 0);
3036 * Called to set the size of the window from SSH's POV.
3038 static void ssh_size(void) {
3039 switch (ssh_state
) {
3040 case SSH_STATE_BEFORE_SIZE
:
3041 case SSH_STATE_PREPACKET
:
3042 case SSH_STATE_CLOSED
:
3043 break; /* do nothing */
3044 case SSH_STATE_INTERMED
:
3045 size_needed
= TRUE
; /* buffer for later */
3047 case SSH_STATE_SESSION
:
3049 if (ssh_version
== 1) {
3050 send_packet(SSH1_CMSG_WINDOW_SIZE
,
3051 PKT_INT
, rows
, PKT_INT
, cols
,
3052 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
3054 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
3055 ssh2_pkt_adduint32(mainchan
->remoteid
);
3056 ssh2_pkt_addstring("window-change");
3057 ssh2_pkt_addbool(0);
3058 ssh2_pkt_adduint32(cols
);
3059 ssh2_pkt_adduint32(rows
);
3060 ssh2_pkt_adduint32(0);
3061 ssh2_pkt_adduint32(0);
3070 * Send Telnet special codes. TS_EOF is useful for `plink', so you
3071 * can send an EOF and collect resulting output (e.g. `plink
3074 static void ssh_special (Telnet_Special code
) {
3075 if (code
== TS_EOF
) {
3076 if (ssh_state
!= SSH_STATE_SESSION
) {
3078 * Buffer the EOF in case we are pre-SESSION, so we can
3079 * send it as soon as we reach SESSION.
3085 if (ssh_version
== 1) {
3086 send_packet(SSH1_CMSG_EOF
, PKT_END
);
3088 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
3089 ssh2_pkt_adduint32(mainchan
->remoteid
);
3092 logevent("Sent EOF message");
3093 } else if (code
== TS_PING
) {
3094 if (ssh_state
== SSH_STATE_CLOSED
|| ssh_state
== SSH_STATE_PREPACKET
)
3096 if (ssh_version
== 1) {
3097 send_packet(SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
3099 ssh2_pkt_init(SSH2_MSG_IGNORE
);
3100 ssh2_pkt_addstring_start();
3108 static Socket
ssh_socket(void) { return s
; }
3110 static int ssh_sendok(void) { return ssh_send_ok
; }
3112 static int ssh_ldisc(int option
) {
3113 if (option
== LD_ECHO
) return ssh_echoing
;
3114 if (option
== LD_EDIT
) return ssh_editing
;
3118 Backend ssh_backend
= {