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, \
23 (s ? sk_close(s), s = NULL : 0), \
24 connection_fatal msg )
26 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
27 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
28 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
29 #define SSH1_CMSG_USER 4 /* 0x4 */
30 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
31 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
32 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
33 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
34 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
35 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
36 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
37 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
38 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
39 #define SSH1_SMSG_FAILURE 15 /* 0xf */
40 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
41 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
42 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
43 #define SSH1_CMSG_EOF 19 /* 0x13 */
44 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
45 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
46 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
47 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
48 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
49 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
50 #define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
51 #define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
52 #define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
53 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
54 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
55 #define SSH1_MSG_IGNORE 32 /* 0x20 */
56 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
57 #define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
58 #define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
59 #define SSH1_MSG_DEBUG 36 /* 0x24 */
60 #define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
61 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
62 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
63 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
64 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
65 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
66 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
68 #define SSH1_AUTH_TIS 5 /* 0x5 */
69 #define SSH1_AUTH_CCARD 16 /* 0x10 */
71 #define SSH_AGENTC_REQUEST_RSA_IDENTITIES 1 /* 0x1 */
72 #define SSH_AGENT_RSA_IDENTITIES_ANSWER 2 /* 0x2 */
73 #define SSH_AGENTC_RSA_CHALLENGE 3 /* 0x3 */
74 #define SSH_AGENT_RSA_RESPONSE 4 /* 0x4 */
75 #define SSH_AGENT_FAILURE 5 /* 0x5 */
76 #define SSH_AGENT_SUCCESS 6 /* 0x6 */
77 #define SSH_AGENTC_ADD_RSA_IDENTITY 7 /* 0x7 */
78 #define SSH_AGENTC_REMOVE_RSA_IDENTITY 8 /* 0x8 */
80 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
81 #define SSH2_MSG_IGNORE 2 /* 0x2 */
82 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
83 #define SSH2_MSG_DEBUG 4 /* 0x4 */
84 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
85 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
86 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
87 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
88 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
89 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
90 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
91 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
92 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
93 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
94 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
95 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
96 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
97 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
98 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
99 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
100 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
101 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
102 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
103 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
104 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
105 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
106 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
107 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
108 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
109 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
111 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
112 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
113 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
114 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
115 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
116 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
117 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
118 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
119 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
120 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
121 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
123 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
124 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
125 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
126 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
128 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
130 #define GET_32BIT(cp) \
131 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
132 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
133 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
134 ((unsigned long)(unsigned char)(cp)[3]))
136 #define PUT_32BIT(cp, value) { \
137 (cp)[0] = (unsigned char)((value) >> 24); \
138 (cp)[1] = (unsigned char)((value) >> 16); \
139 (cp)[2] = (unsigned char)((value) >> 8); \
140 (cp)[3] = (unsigned char)(value); }
142 enum { PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
};
144 /* Coroutine mechanics for the sillier bits of the code */
145 #define crBegin1 static int crLine = 0;
146 #define crBegin2 switch(crLine) { case 0:;
147 #define crBegin crBegin1; crBegin2;
148 #define crFinish(z) } crLine = 0; return (z)
149 #define crFinishV } crLine = 0; return
150 #define crReturn(z) \
152 crLine=__LINE__; return (z); case __LINE__:;\
156 crLine=__LINE__; return; case __LINE__:;\
158 #define crStop(z) do{ crLine = 0; return (z); }while(0)
159 #define crStopV do{ crLine = 0; return; }while(0)
160 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
161 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
163 extern const struct ssh_cipher ssh_3des
;
164 extern const struct ssh_cipher ssh_3des_ssh2
;
165 extern const struct ssh_cipher ssh_des
;
166 extern const struct ssh_cipher ssh_blowfish_ssh1
;
167 extern const struct ssh_cipher ssh_blowfish_ssh2
;
169 extern char *x11_init (Socket
*, char *, void *);
170 extern void x11_close (Socket
);
171 extern void x11_send (Socket
, char *, int);
172 extern void x11_invent_auth(char *, int, char *, int);
175 * Ciphers for SSH2. We miss out single-DES because it isn't
176 * supported; also 3DES and Blowfish are both done differently from
177 * SSH1. (3DES uses outer chaining; Blowfish has the opposite
178 * endianness and different-sized keys.)
180 const static struct ssh_cipher
*ciphers
[] = { &ssh_blowfish_ssh2
, &ssh_3des_ssh2
};
182 extern const struct ssh_kex ssh_diffiehellman
;
183 const static struct ssh_kex
*kex_algs
[] = { &ssh_diffiehellman
};
185 extern const struct ssh_signkey ssh_dss
;
186 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_dss
};
188 extern const struct ssh_mac ssh_md5
, ssh_sha1
, ssh_sha1_buggy
;
190 static void nullmac_key(unsigned char *key
) { }
191 static void nullmac_generate(unsigned char *blk
, int len
, unsigned long seq
) { }
192 static int nullmac_verify(unsigned char *blk
, int len
, unsigned long seq
) { return 1; }
193 const static struct ssh_mac ssh_mac_none
= {
194 nullmac_key
, nullmac_key
, nullmac_generate
, nullmac_verify
, "none", 0
196 const static struct ssh_mac
*macs
[] = {
197 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
};
198 const static struct ssh_mac
*buggymacs
[] = {
199 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
};
201 static void ssh_comp_none_init(void) { }
202 static int ssh_comp_none_block(unsigned char *block
, int len
,
203 unsigned char **outblock
, int *outlen
) {
206 const static struct ssh_compress ssh_comp_none
= {
208 ssh_comp_none_init
, ssh_comp_none_block
,
209 ssh_comp_none_init
, ssh_comp_none_block
211 extern const struct ssh_compress ssh_zlib
;
212 const static struct ssh_compress
*compressions
[] = {
213 &ssh_zlib
, &ssh_comp_none
};
215 enum { /* channel types */
222 * 2-3-4 tree storing channels.
225 unsigned remoteid
, localid
;
228 struct ssh2_data_channel
{
229 unsigned char *outbuffer
;
230 unsigned outbuflen
, outbufsize
;
231 unsigned remwindow
, remmaxpkt
;
234 struct ssh_agent_channel
{
235 unsigned char *message
;
236 unsigned char msglen
[4];
237 int lensofar
, totallen
;
239 struct ssh_x11_channel
{
254 static SHA_State exhash
, exhashbase
;
256 static Socket s
= NULL
;
258 static unsigned char session_key
[32];
259 static int ssh1_compressing
;
260 static int ssh_agentfwd_enabled
;
261 static int ssh_X11_fwd_enabled
;
262 static const struct ssh_cipher
*cipher
= NULL
;
263 static const struct ssh_cipher
*cscipher
= NULL
;
264 static const struct ssh_cipher
*sccipher
= NULL
;
265 static const struct ssh_mac
*csmac
= NULL
;
266 static const struct ssh_mac
*scmac
= NULL
;
267 static const struct ssh_compress
*cscomp
= NULL
;
268 static const struct ssh_compress
*sccomp
= NULL
;
269 static const struct ssh_kex
*kex
= NULL
;
270 static const struct ssh_signkey
*hostkey
= NULL
;
271 int (*ssh_get_password
)(const char *prompt
, char *str
, int maxlen
) = NULL
;
273 static char *savedhost
;
274 static int savedport
;
275 static int ssh_send_ok
;
276 static int ssh_echoing
, ssh_editing
;
278 static tree234
*ssh_channels
; /* indexed by local id */
279 static struct ssh_channel
*mainchan
; /* primary session channel */
283 SSH_STATE_BEFORE_SIZE
,
287 } ssh_state
= SSH_STATE_PREPACKET
;
289 static int size_needed
= FALSE
, eof_needed
= FALSE
;
291 static struct Packet pktin
= { 0, 0, NULL
, NULL
, 0 };
292 static struct Packet pktout
= { 0, 0, NULL
, NULL
, 0 };
293 static unsigned char *deferred_send_data
= NULL
;
294 static int deferred_len
= 0, deferred_size
= 0;
296 static int ssh_version
;
297 static void (*ssh_protocol
)(unsigned char *in
, int inlen
, int ispkt
);
298 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
);
299 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
);
300 static void ssh_size(void);
301 static void ssh_special (Telnet_Special
);
302 static void ssh2_try_send(struct ssh_channel
*c
);
303 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
305 static int (*s_rdpkt
)(unsigned char **data
, int *datalen
);
307 static struct rdpkt1_state_tag
{
308 long len
, pad
, biglen
, to_read
;
309 unsigned long realcrc
, gotcrc
;
315 static struct rdpkt2_state_tag
{
316 long len
, pad
, payload
, packetlen
, maclen
;
319 unsigned long incoming_sequence
;
322 static int ssh_channelcmp(void *av
, void *bv
) {
323 struct ssh_channel
*a
= (struct ssh_channel
*)av
;
324 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
325 if (a
->localid
< b
->localid
) return -1;
326 if (a
->localid
> b
->localid
) return +1;
329 static int ssh_channelfind(void *av
, void *bv
) {
330 unsigned *a
= (unsigned *)av
;
331 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
332 if (*a
< b
->localid
) return -1;
333 if (*a
> b
->localid
) return +1;
337 static void c_write (char *buf
, int len
) {
338 if ((flags
& FLAG_STDERR
)) {
340 for (i
= 0; i
< len
; i
++)
342 fputc(buf
[i
], stderr
);
345 from_backend(1, buf
, len
);
349 * Collect incoming data in the incoming packet buffer.
350 * Decipher and verify the packet when it is completely read.
351 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
352 * Update the *data and *datalen variables.
353 * Return the additional nr of bytes needed, or 0 when
354 * a complete packet is available.
356 static int ssh1_rdpkt(unsigned char **data
, int *datalen
)
358 struct rdpkt1_state_tag
*st
= &rdpkt1_state
;
367 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
368 while ((*datalen
) == 0)
370 st
->len
= (st
->len
<< 8) + **data
;
371 (*data
)++, (*datalen
)--;
375 if (st
->len
== 0x52656d6f) { /* "Remo"te server has closed ... */
376 st
->len
= 0x300; /* big enough to carry to end */
380 st
->pad
= 8 - (st
->len
% 8);
381 st
->biglen
= st
->len
+ st
->pad
;
382 pktin
.length
= st
->len
- 5;
384 if (pktin
.maxlen
< st
->biglen
) {
385 pktin
.maxlen
= st
->biglen
;
386 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->biglen
+APIEXTRA
) :
387 srealloc(pktin
.data
, st
->biglen
+APIEXTRA
));
389 fatalbox("Out of memory");
392 st
->to_read
= st
->biglen
;
394 while (st
->to_read
> 0) {
395 st
->chunk
= st
->to_read
;
396 while ((*datalen
) == 0)
397 crReturn(st
->to_read
);
398 if (st
->chunk
> (*datalen
))
399 st
->chunk
= (*datalen
);
400 memcpy(st
->p
, *data
, st
->chunk
);
402 *datalen
-= st
->chunk
;
404 st
->to_read
-= st
->chunk
;
408 cipher
->decrypt(pktin
.data
, st
->biglen
);
410 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
411 for (st
->i
= 0; st
->i
< st
->biglen
; st
->i
++)
412 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
416 st
->realcrc
= crc32(pktin
.data
, st
->biglen
-4);
417 st
->gotcrc
= GET_32BIT(pktin
.data
+st
->biglen
-4);
418 if (st
->gotcrc
!= st
->realcrc
) {
419 bombout(("Incorrect CRC received on packet"));
423 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
425 if (ssh1_compressing
) {
426 unsigned char *decompblk
;
430 debug(("Packet payload pre-decompression:\n"));
431 for (i
= -1; i
< pktin
.length
; i
++)
432 debug((" %02x", (unsigned char)pktin
.body
[i
]));
435 zlib_decompress_block(pktin
.body
-1, pktin
.length
+1,
436 &decompblk
, &decomplen
);
438 if (pktin
.maxlen
< st
->pad
+ decomplen
) {
439 pktin
.maxlen
= st
->pad
+ decomplen
;
440 pktin
.data
= srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
);
441 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
443 fatalbox("Out of memory");
446 memcpy(pktin
.body
-1, decompblk
, decomplen
);
448 pktin
.length
= decomplen
-1;
450 debug(("Packet payload post-decompression:\n"));
451 for (i
= -1; i
< pktin
.length
; i
++)
452 debug((" %02x", (unsigned char)pktin
.body
[i
]));
457 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
458 pktin
.type
== SSH1_SMSG_STDERR_DATA
||
459 pktin
.type
== SSH1_MSG_DEBUG
||
460 pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
461 pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
462 long strlen
= GET_32BIT(pktin
.body
);
463 if (strlen
+ 4 != pktin
.length
) {
464 bombout(("Received data packet with bogus string length"));
469 pktin
.type
= pktin
.body
[-1];
471 if (pktin
.type
== SSH1_MSG_DEBUG
) {
472 /* log debug message */
474 int strlen
= GET_32BIT(pktin
.body
);
475 strcpy(buf
, "Remote: ");
476 if (strlen
> 70) strlen
= 70;
477 memcpy(buf
+8, pktin
.body
+4, strlen
);
478 buf
[8+strlen
] = '\0';
481 } else if (pktin
.type
== SSH1_MSG_IGNORE
) {
489 static int ssh2_rdpkt(unsigned char **data
, int *datalen
)
491 struct rdpkt2_state_tag
*st
= &rdpkt2_state
;
499 st
->cipherblk
= sccipher
->blksize
;
502 if (st
->cipherblk
< 8)
505 if (pktin
.maxlen
< st
->cipherblk
) {
506 pktin
.maxlen
= st
->cipherblk
;
507 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->cipherblk
+APIEXTRA
) :
508 srealloc(pktin
.data
, st
->cipherblk
+APIEXTRA
));
510 fatalbox("Out of memory");
514 * Acquire and decrypt the first block of the packet. This will
515 * contain the length and padding details.
517 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
518 while ((*datalen
) == 0)
519 crReturn(st
->cipherblk
-st
->i
);
520 pktin
.data
[st
->i
] = *(*data
)++;
524 if (!memcmp(pktin
.data
, "Remo", 4)) {/* "Remo"te server has closed ... */
529 sccipher
->decrypt(pktin
.data
, st
->cipherblk
);
532 * Now get the length and padding figures.
534 st
->len
= GET_32BIT(pktin
.data
);
535 st
->pad
= pktin
.data
[4];
538 * This enables us to deduce the payload length.
540 st
->payload
= st
->len
- st
->pad
- 1;
542 pktin
.length
= st
->payload
+ 5;
545 * So now we can work out the total packet length.
547 st
->packetlen
= st
->len
+ 4;
548 st
->maclen
= scmac ? scmac
->len
: 0;
551 * Adjust memory allocation if packet is too big.
553 if (pktin
.maxlen
< st
->packetlen
+st
->maclen
) {
554 pktin
.maxlen
= st
->packetlen
+st
->maclen
;
555 pktin
.data
= (pktin
.data
== NULL ?
smalloc(pktin
.maxlen
+APIEXTRA
) :
556 srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
558 fatalbox("Out of memory");
562 * Read and decrypt the remainder of the packet.
564 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
; st
->i
++) {
565 while ((*datalen
) == 0)
566 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
567 pktin
.data
[st
->i
] = *(*data
)++;
570 /* Decrypt everything _except_ the MAC. */
572 sccipher
->decrypt(pktin
.data
+ st
->cipherblk
,
573 st
->packetlen
- st
->cipherblk
);
576 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
577 for (st
->i
= 0; st
->i
< st
->packetlen
; st
->i
++)
578 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
585 if (scmac
&& !scmac
->verify(pktin
.data
, st
->len
+4, st
->incoming_sequence
)) {
586 bombout(("Incorrect MAC received on packet"));
589 st
->incoming_sequence
++; /* whether or not we MACed */
592 * Decompress packet payload.
595 unsigned char *newpayload
;
597 if (sccomp
&& sccomp
->decompress(pktin
.data
+5, pktin
.length
-5,
598 &newpayload
, &newlen
)) {
599 if (pktin
.maxlen
< newlen
+5) {
600 pktin
.maxlen
= newlen
+5;
601 pktin
.data
= (pktin
.data
== NULL ?
smalloc(pktin
.maxlen
+APIEXTRA
) :
602 srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
604 fatalbox("Out of memory");
606 pktin
.length
= 5 + newlen
;
607 memcpy(pktin
.data
+5, newpayload
, newlen
);
609 debug(("Post-decompression payload:\r\n"));
610 for (st
->i
= 0; st
->i
< newlen
; st
->i
++)
611 debug((" %02x", (unsigned char)pktin
.data
[5+st
->i
]));
620 pktin
.type
= pktin
.data
[5];
622 if (pktin
.type
== SSH2_MSG_IGNORE
|| pktin
.type
== SSH2_MSG_DEBUG
)
623 goto next_packet
; /* FIXME: print DEBUG message */
628 static void ssh1_pktout_size(int len
) {
631 len
+= 5; /* type and CRC */
635 pktout
.length
= len
-5;
636 if (pktout
.maxlen
< biglen
) {
637 pktout
.maxlen
= biglen
;
639 /* Allocate enough buffer space for extra block
640 * for MS CryptEncrypt() */
641 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+12) :
642 srealloc(pktout
.data
, biglen
+12));
644 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+4) :
645 srealloc(pktout
.data
, biglen
+4));
648 fatalbox("Out of memory");
650 pktout
.body
= pktout
.data
+4+pad
+1;
653 static void s_wrpkt_start(int type
, int len
) {
654 ssh1_pktout_size(len
);
658 static void s_wrpkt(void) {
659 int pad
, len
, biglen
, i
;
662 pktout
.body
[-1] = pktout
.type
;
664 if (ssh1_compressing
) {
665 unsigned char *compblk
;
668 debug(("Packet payload pre-compression:\n"));
669 for (i
= -1; i
< pktout
.length
; i
++)
670 debug((" %02x", (unsigned char)pktout
.body
[i
]));
673 zlib_compress_block(pktout
.body
-1, pktout
.length
+1,
675 ssh1_pktout_size(complen
-1);
676 memcpy(pktout
.body
-1, compblk
, complen
);
679 debug(("Packet payload post-compression:\n"));
680 for (i
= -1; i
< pktout
.length
; i
++)
681 debug((" %02x", (unsigned char)pktout
.body
[i
]));
686 len
= pktout
.length
+ 5; /* type and CRC */
690 for (i
=0; i
<pad
; i
++)
691 pktout
.data
[i
+4] = random_byte();
692 crc
= crc32(pktout
.data
+4, biglen
-4);
693 PUT_32BIT(pktout
.data
+biglen
, crc
);
694 PUT_32BIT(pktout
.data
, len
);
697 debug(("Sending packet len=%d\r\n", biglen
+4));
698 for (i
= 0; i
< biglen
+4; i
++)
699 debug((" %02x", (unsigned char)pktout
.data
[i
]));
703 cipher
->encrypt(pktout
.data
+4, biglen
);
705 sk_write(s
, pktout
.data
, biglen
+4);
709 * Construct a packet with the specified contents and
710 * send it to the server.
712 static void send_packet(int pkttype
, ...)
715 unsigned char *p
, *argp
, argchar
;
716 unsigned long argint
;
717 int pktlen
, argtype
, arglen
;
721 va_start(args
, pkttype
);
722 while ((argtype
= va_arg(args
, int)) != PKT_END
) {
725 (void) va_arg(args
, int);
729 (void) va_arg(args
, char);
733 (void) va_arg(args
, unsigned char *);
734 arglen
= va_arg(args
, int);
738 argp
= va_arg(args
, unsigned char *);
739 arglen
= strlen(argp
);
740 pktlen
+= 4 + arglen
;
743 bn
= va_arg(args
, Bignum
);
744 pktlen
+= ssh1_bignum_length(bn
);
752 s_wrpkt_start(pkttype
, pktlen
);
755 va_start(args
, pkttype
);
756 while ((argtype
= va_arg(args
, int)) != PKT_END
) {
759 argint
= va_arg(args
, int);
760 PUT_32BIT(p
, argint
);
764 argchar
= va_arg(args
, unsigned char);
769 argp
= va_arg(args
, unsigned char *);
770 arglen
= va_arg(args
, int);
771 memcpy(p
, argp
, arglen
);
775 argp
= va_arg(args
, unsigned char *);
776 arglen
= strlen(argp
);
777 PUT_32BIT(p
, arglen
);
778 memcpy(p
+ 4, argp
, arglen
);
782 bn
= va_arg(args
, Bignum
);
783 p
+= ssh1_write_bignum(p
, bn
);
792 static int ssh_versioncmp(char *a
, char *b
) {
794 unsigned long av
, bv
;
796 av
= strtoul(a
, &ae
, 10);
797 bv
= strtoul(b
, &be
, 10);
798 if (av
!= bv
) return (av
< bv ?
-1 : +1);
799 if (*ae
== '.') ae
++;
800 if (*be
== '.') be
++;
801 av
= strtoul(ae
, &ae
, 10);
802 bv
= strtoul(be
, &be
, 10);
803 if (av
!= bv
) return (av
< bv ?
-1 : +1);
809 * Utility routine for putting an SSH-protocol `string' into a SHA
813 static void sha_string(SHA_State
*s
, void *str
, int len
) {
814 unsigned char lenblk
[4];
815 PUT_32BIT(lenblk
, len
);
816 SHA_Bytes(s
, lenblk
, 4);
817 SHA_Bytes(s
, str
, len
);
821 * SSH2 packet construction functions.
823 static void ssh2_pkt_ensure(int length
) {
824 if (pktout
.maxlen
< length
) {
825 pktout
.maxlen
= length
+ 256;
826 pktout
.data
= (pktout
.data
== NULL ?
smalloc(pktout
.maxlen
+APIEXTRA
) :
827 srealloc(pktout
.data
, pktout
.maxlen
+APIEXTRA
));
829 fatalbox("Out of memory");
832 static void ssh2_pkt_adddata(void *data
, int len
) {
833 pktout
.length
+= len
;
834 ssh2_pkt_ensure(pktout
.length
);
835 memcpy(pktout
.data
+pktout
.length
-len
, data
, len
);
837 static void ssh2_pkt_addbyte(unsigned char byte
) {
838 ssh2_pkt_adddata(&byte
, 1);
840 static void ssh2_pkt_init(int pkt_type
) {
842 ssh2_pkt_addbyte((unsigned char)pkt_type
);
844 static void ssh2_pkt_addbool(unsigned char value
) {
845 ssh2_pkt_adddata(&value
, 1);
847 static void ssh2_pkt_adduint32(unsigned long value
) {
850 ssh2_pkt_adddata(x
, 4);
852 static void ssh2_pkt_addstring_start(void) {
853 ssh2_pkt_adduint32(0);
854 pktout
.savedpos
= pktout
.length
;
856 static void ssh2_pkt_addstring_str(char *data
) {
857 ssh2_pkt_adddata(data
, strlen(data
));
858 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
859 pktout
.length
- pktout
.savedpos
);
861 static void ssh2_pkt_addstring_data(char *data
, int len
) {
862 ssh2_pkt_adddata(data
, len
);
863 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
864 pktout
.length
- pktout
.savedpos
);
866 static void ssh2_pkt_addstring(char *data
) {
867 ssh2_pkt_addstring_start();
868 ssh2_pkt_addstring_str(data
);
870 static char *ssh2_mpint_fmt(Bignum b
, int *len
) {
872 int i
, n
= (ssh1_bignum_bitcount(b
)+7)/8;
875 fatalbox("out of memory");
877 for (i
= 1; i
<= n
; i
++)
878 p
[i
] = bignum_byte(b
, n
-i
);
880 while (i
<= n
&& p
[i
] == 0 && (p
[i
+1] & 0x80) == 0)
882 memmove(p
, p
+i
, n
+1-i
);
886 static void ssh2_pkt_addmp(Bignum b
) {
889 p
= ssh2_mpint_fmt(b
, &len
);
890 ssh2_pkt_addstring_start();
891 ssh2_pkt_addstring_data(p
, len
);
896 * Construct an SSH2 final-form packet: compress it, encrypt it,
897 * put the MAC on it. Final packet, ready to be sent, is stored in
898 * pktout.data. Total length is returned.
900 static int ssh2_pkt_construct(void) {
901 int cipherblk
, maclen
, padding
, i
;
902 static unsigned long outgoing_sequence
= 0;
905 * Compress packet payload.
908 debug(("Pre-compression payload:\r\n"));
909 for (i
= 5; i
< pktout
.length
; i
++)
910 debug((" %02x", (unsigned char)pktout
.data
[i
]));
914 unsigned char *newpayload
;
916 if (cscomp
&& cscomp
->compress(pktout
.data
+5, pktout
.length
-5,
917 &newpayload
, &newlen
)) {
919 ssh2_pkt_adddata(newpayload
, newlen
);
925 * Add padding. At least four bytes, and must also bring total
926 * length (minus MAC) up to a multiple of the block size.
928 cipherblk
= cipher ? cipher
->blksize
: 8; /* block size */
929 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
931 padding
+= (cipherblk
- (pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
932 maclen
= csmac ? csmac
->len
: 0;
933 ssh2_pkt_ensure(pktout
.length
+ padding
+ maclen
);
934 pktout
.data
[4] = padding
;
935 for (i
= 0; i
< padding
; i
++)
936 pktout
.data
[pktout
.length
+ i
] = random_byte();
937 PUT_32BIT(pktout
.data
, pktout
.length
+ padding
- 4);
939 csmac
->generate(pktout
.data
, pktout
.length
+ padding
,
941 outgoing_sequence
++; /* whether or not we MACed */
944 debug(("Sending packet len=%d\r\n", pktout
.length
+padding
));
945 for (i
= 0; i
< pktout
.length
+padding
; i
++)
946 debug((" %02x", (unsigned char)pktout
.data
[i
]));
951 cscipher
->encrypt(pktout
.data
, pktout
.length
+ padding
);
953 /* Ready-to-send packet starts at pktout.data. We return length. */
954 return pktout
.length
+ padding
+ maclen
;
958 * Construct and send an SSH2 packet immediately.
960 static void ssh2_pkt_send(void) {
961 int len
= ssh2_pkt_construct();
962 sk_write(s
, pktout
.data
, len
);
966 * Construct an SSH2 packet and add it to a deferred data block.
967 * Useful for sending multiple packets in a single sk_write() call,
968 * to prevent a traffic-analysing listener from being able to work
969 * out the length of any particular packet (such as the password
972 * Note that because SSH2 sequence-numbers its packets, this can
973 * NOT be used as an m4-style `defer' allowing packets to be
974 * constructed in one order and sent in another.
976 static void ssh2_pkt_defer(void) {
977 int len
= ssh2_pkt_construct();
978 if (deferred_len
+ len
> deferred_size
) {
979 deferred_size
= deferred_len
+ len
+ 128;
980 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
982 memcpy(deferred_send_data
+deferred_len
, pktout
.data
, len
);
987 * Send the whole deferred data block constructed by
990 static void ssh2_pkt_defersend(void) {
991 sk_write(s
, deferred_send_data
, deferred_len
);
992 deferred_len
= deferred_size
= 0;
993 sfree(deferred_send_data
);
994 deferred_send_data
= NULL
;
998 void bndebug(char *string
, Bignum b
) {
1001 p
= ssh2_mpint_fmt(b
, &len
);
1002 debug(("%s", string
));
1003 for (i
= 0; i
< len
; i
++)
1004 debug((" %02x", p
[i
]));
1010 static void sha_mpint(SHA_State
*s
, Bignum b
) {
1013 p
= ssh2_mpint_fmt(b
, &len
);
1014 sha_string(s
, p
, len
);
1019 * SSH2 packet decode functions.
1021 static unsigned long ssh2_pkt_getuint32(void) {
1022 unsigned long value
;
1023 if (pktin
.length
- pktin
.savedpos
< 4)
1024 return 0; /* arrgh, no way to decline (FIXME?) */
1025 value
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
1026 pktin
.savedpos
+= 4;
1029 static void ssh2_pkt_getstring(char **p
, int *length
) {
1031 if (pktin
.length
- pktin
.savedpos
< 4)
1033 *length
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
1034 pktin
.savedpos
+= 4;
1035 if (pktin
.length
- pktin
.savedpos
< *length
)
1037 *p
= pktin
.data
+pktin
.savedpos
;
1038 pktin
.savedpos
+= *length
;
1040 static Bignum
ssh2_pkt_getmp(void) {
1045 ssh2_pkt_getstring(&p
, &length
);
1049 bombout(("internal error: Can't handle negative mpints"));
1052 b
= bignum_from_bytes(p
, length
);
1056 static int do_ssh_init(unsigned char c
) {
1058 static char version
[10];
1059 static char vstring
[80];
1060 static char vlog
[sizeof(vstring
)+20];
1065 /* Search for the string "SSH-" in the input. */
1068 static const int transS
[] = { 1, 2, 2, 1 };
1069 static const int transH
[] = { 0, 0, 3, 0 };
1070 static const int transminus
[] = { 0, 0, 0, -1 };
1071 if (c
== 'S') i
= transS
[i
];
1072 else if (c
== 'H') i
= transH
[i
];
1073 else if (c
== '-') i
= transminus
[i
];
1077 crReturn(1); /* get another character */
1080 strcpy(vstring
, "SSH-");
1084 crReturn(1); /* get another char */
1085 if (vsp
< vstring
+sizeof(vstring
)-1)
1091 } else if (i
< sizeof(version
)-1)
1098 ssh_agentfwd_enabled
= FALSE
;
1099 rdpkt2_state
.incoming_sequence
= 0;
1102 sprintf(vlog
, "Server version: %s", vstring
);
1103 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1107 * Server version "1.99" means we can choose whether we use v1
1108 * or v2 protocol. Choice is based on cfg.sshprot.
1110 if (ssh_versioncmp(version
, cfg
.sshprot
== 1 ?
"2.0" : "1.99") >= 0) {
1112 * This is a v2 server. Begin v2 protocol.
1114 char *verstring
= "SSH-2.0-PuTTY";
1115 SHA_Init(&exhashbase
);
1117 * Hash our version string and their version string.
1119 sha_string(&exhashbase
, verstring
, strlen(verstring
));
1120 sha_string(&exhashbase
, vstring
, strcspn(vstring
, "\r\n"));
1121 sprintf(vstring
, "%s\n", verstring
);
1122 sprintf(vlog
, "We claim version: %s", verstring
);
1124 logevent("Using SSH protocol version 2");
1125 sk_write(s
, vstring
, strlen(vstring
));
1126 ssh_protocol
= ssh2_protocol
;
1128 s_rdpkt
= ssh2_rdpkt
;
1131 * This is a v1 server. Begin v1 protocol.
1133 sprintf(vstring
, "SSH-%s-PuTTY\n",
1134 (ssh_versioncmp(version
, "1.5") <= 0 ? version
: "1.5"));
1135 sprintf(vlog
, "We claim version: %s", vstring
);
1136 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1138 logevent("Using SSH protocol version 1");
1139 sk_write(s
, vstring
, strlen(vstring
));
1140 ssh_protocol
= ssh1_protocol
;
1142 s_rdpkt
= ssh1_rdpkt
;
1144 ssh_state
= SSH_STATE_BEFORE_SIZE
;
1149 static void ssh_gotdata(unsigned char *data
, int datalen
)
1154 * To begin with, feed the characters one by one to the
1155 * protocol initialisation / selection function do_ssh_init().
1156 * When that returns 0, we're done with the initial greeting
1157 * exchange and can move on to packet discipline.
1162 crReturnV
; /* more data please */
1163 ret
= do_ssh_init(*data
);
1170 * We emerge from that loop when the initial negotiation is
1171 * over and we have selected an s_rdpkt function. Now pass
1172 * everything to s_rdpkt, and then pass the resulting packets
1173 * to the proper protocol handler.
1178 while (datalen
> 0) {
1179 if ( s_rdpkt(&data
, &datalen
) == 0 ) {
1180 ssh_protocol(NULL
, 0, 1);
1181 if (ssh_state
== SSH_STATE_CLOSED
) {
1191 static int ssh_receive(Socket skt
, int urgent
, char *data
, int len
) {
1193 /* A socket error has occurred. */
1194 ssh_state
= SSH_STATE_CLOSED
;
1197 connection_fatal(data
);
1200 /* Connection has closed. */
1201 ssh_state
= SSH_STATE_CLOSED
;
1206 ssh_gotdata (data
, len
);
1207 if (ssh_state
== SSH_STATE_CLOSED
) {
1218 * Connect to specified host and port.
1219 * Returns an error message, or NULL on success.
1220 * Also places the canonical host name into `realhost'.
1222 static char *connect_to_host(char *host
, int port
, char **realhost
)
1231 savedhost
= smalloc(1+strlen(host
));
1233 fatalbox("Out of memory");
1234 strcpy(savedhost
, host
);
1237 port
= 22; /* default ssh port */
1250 addr
= sk_namelookup(host
, realhost
);
1251 if ( (err
= sk_addr_error(addr
)) )
1261 s
= sk_new(addr
, port
, 0, 1, ssh_receive
);
1262 if ( (err
= sk_socket_error(s
)) )
1266 sk_write(s
, "connect ", 8);
1267 sk_write(s
, FWhost
, strlen(FWhost
));
1270 sprintf(buf
, " %d\n", FWport
);
1271 sk_write(s
, buf
, strlen(buf
));
1279 * Handle the key exchange and user authentication phases.
1281 static int do_ssh1_login(unsigned char *in
, int inlen
, int ispkt
)
1284 unsigned char *rsabuf
, *keystr1
, *keystr2
;
1285 unsigned char cookie
[8];
1286 struct RSAKey servkey
, hostkey
;
1287 struct MD5Context md5c
;
1288 static unsigned long supported_ciphers_mask
, supported_auths_mask
;
1289 static int tried_publickey
;
1290 static unsigned char session_id
[16];
1292 static char username
[100];
1296 if (!ispkt
) crWaitUntil(ispkt
);
1298 if (pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
1299 bombout(("Public key packet not received"));
1303 logevent("Received public keys");
1305 memcpy(cookie
, pktin
.body
, 8);
1307 i
= makekey(pktin
.body
+8, &servkey
, &keystr1
, 0);
1308 j
= makekey(pktin
.body
+8+i
, &hostkey
, &keystr2
, 0);
1311 * Log the host key fingerprint.
1315 logevent("Host key fingerprint is:");
1316 strcpy(logmsg
, " ");
1317 hostkey
.comment
= NULL
;
1318 rsa_fingerprint(logmsg
+strlen(logmsg
), sizeof(logmsg
)-strlen(logmsg
),
1323 supported_ciphers_mask
= GET_32BIT(pktin
.body
+12+i
+j
);
1324 supported_auths_mask
= GET_32BIT(pktin
.body
+16+i
+j
);
1327 MD5Update(&md5c
, keystr2
, hostkey
.bytes
);
1328 MD5Update(&md5c
, keystr1
, servkey
.bytes
);
1329 MD5Update(&md5c
, pktin
.body
, 8);
1330 MD5Final(session_id
, &md5c
);
1332 for (i
=0; i
<32; i
++)
1333 session_key
[i
] = random_byte();
1335 len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
1337 rsabuf
= smalloc(len
);
1339 fatalbox("Out of memory");
1342 * Verify the host key.
1346 * First format the key into a string.
1348 int len
= rsastr_len(&hostkey
);
1349 char fingerprint
[100];
1350 char *keystr
= smalloc(len
);
1352 fatalbox("Out of memory");
1353 rsastr_fmt(keystr
, &hostkey
);
1354 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
1355 verify_ssh_host_key(savedhost
, savedport
, "rsa", keystr
, fingerprint
);
1359 for (i
=0; i
<32; i
++) {
1360 rsabuf
[i
] = session_key
[i
];
1362 rsabuf
[i
] ^= session_id
[i
];
1365 if (hostkey
.bytes
> servkey
.bytes
) {
1366 rsaencrypt(rsabuf
, 32, &servkey
);
1367 rsaencrypt(rsabuf
, servkey
.bytes
, &hostkey
);
1369 rsaencrypt(rsabuf
, 32, &hostkey
);
1370 rsaencrypt(rsabuf
, hostkey
.bytes
, &servkey
);
1373 logevent("Encrypted session key");
1375 cipher_type
= cfg
.cipher
== CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH
:
1376 cfg
.cipher
== CIPHER_DES ? SSH_CIPHER_DES
:
1378 if ((supported_ciphers_mask
& (1 << cipher_type
)) == 0) {
1379 c_write("Selected cipher not supported, falling back to 3DES\r\n", 53);
1380 cipher_type
= SSH_CIPHER_3DES
;
1382 switch (cipher_type
) {
1383 case SSH_CIPHER_3DES
: logevent("Using 3DES encryption"); break;
1384 case SSH_CIPHER_DES
: logevent("Using single-DES encryption"); break;
1385 case SSH_CIPHER_BLOWFISH
: logevent("Using Blowfish encryption"); break;
1388 send_packet(SSH1_CMSG_SESSION_KEY
,
1389 PKT_CHAR
, cipher_type
,
1390 PKT_DATA
, cookie
, 8,
1391 PKT_CHAR
, (len
*8) >> 8, PKT_CHAR
, (len
*8) & 0xFF,
1392 PKT_DATA
, rsabuf
, len
,
1396 logevent("Trying to enable encryption...");
1400 cipher
= cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
1401 cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
1403 cipher
->sesskey(session_key
);
1407 if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1408 bombout(("Encryption not successfully enabled"));
1412 logevent("Successfully started encryption");
1418 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
1419 c_write("login as: ", 10);
1422 crWaitUntil(!ispkt
);
1423 while (inlen
--) switch (c
= *in
++) {
1430 c_write("\b \b", 3);
1436 c_write("\b \b", 3);
1445 if (((c
>= ' ' && c
<= '~') ||
1446 ((unsigned char)c
>= 160)) && pos
< 40) {
1447 username
[pos
++] = c
;
1454 username
[strcspn(username
, "\n\r")] = '\0';
1456 strncpy(username
, cfg
.username
, 99);
1457 username
[99] = '\0';
1460 send_packet(SSH1_CMSG_USER
, PKT_STR
, username
, PKT_END
);
1462 char userlog
[22+sizeof(username
)];
1463 sprintf(userlog
, "Sent username \"%s\"", username
);
1465 if (flags
& FLAG_INTERACTIVE
&&
1466 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
1467 strcat(userlog
, "\r\n");
1468 c_write(userlog
, strlen(userlog
));
1475 tried_publickey
= 0;
1477 while (pktin
.type
== SSH1_SMSG_FAILURE
) {
1478 static char password
[100];
1479 static char prompt
[200];
1482 static int pwpkt_type
;
1484 * Show password prompt, having first obtained it via a TIS
1485 * or CryptoCard exchange if we're doing TIS or CryptoCard
1488 pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
1489 if (agent_exists()) {
1491 * Attempt RSA authentication using Pageant.
1493 static unsigned char request
[5], *response
, *p
;
1494 static int responselen
;
1495 static int i
, nkeys
;
1496 static int authed
= FALSE
;
1499 logevent("Pageant is running. Requesting keys.");
1501 /* Request the keys held by the agent. */
1502 PUT_32BIT(request
, 1);
1503 request
[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES
;
1504 agent_query(request
, 5, &r
, &responselen
);
1505 response
= (unsigned char *)r
;
1508 nkeys
= GET_32BIT(p
); p
+= 4;
1509 { char buf
[64]; sprintf(buf
, "Pageant has %d keys", nkeys
);
1511 for (i
= 0; i
< nkeys
; i
++) {
1512 static struct RSAKey key
;
1513 static Bignum challenge
;
1514 static char *commentp
;
1515 static int commentlen
;
1517 { char buf
[64]; sprintf(buf
, "Trying Pageant key #%d", i
);
1520 p
+= ssh1_read_bignum(p
, &key
.exponent
);
1521 p
+= ssh1_read_bignum(p
, &key
.modulus
);
1522 commentlen
= GET_32BIT(p
); p
+= 4;
1523 commentp
= p
; p
+= commentlen
;
1524 send_packet(SSH1_CMSG_AUTH_RSA
,
1525 PKT_BIGNUM
, key
.modulus
, PKT_END
);
1527 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1528 logevent("Key refused");
1531 logevent("Received RSA challenge");
1532 ssh1_read_bignum(pktin
.body
, &challenge
);
1534 char *agentreq
, *q
, *ret
;
1536 len
= 1 + 4; /* message type, bit count */
1537 len
+= ssh1_bignum_length(key
.exponent
);
1538 len
+= ssh1_bignum_length(key
.modulus
);
1539 len
+= ssh1_bignum_length(challenge
);
1540 len
+= 16; /* session id */
1541 len
+= 4; /* response format */
1542 agentreq
= smalloc(4 + len
);
1543 PUT_32BIT(agentreq
, len
);
1545 *q
++ = SSH_AGENTC_RSA_CHALLENGE
;
1546 PUT_32BIT(q
, ssh1_bignum_bitcount(key
.modulus
));
1548 q
+= ssh1_write_bignum(q
, key
.exponent
);
1549 q
+= ssh1_write_bignum(q
, key
.modulus
);
1550 q
+= ssh1_write_bignum(q
, challenge
);
1551 memcpy(q
, session_id
, 16); q
+= 16;
1552 PUT_32BIT(q
, 1); /* response format */
1553 agent_query(agentreq
, len
+4, &ret
, &retlen
);
1556 if (ret
[4] == SSH_AGENT_RSA_RESPONSE
) {
1557 logevent("Sending Pageant's response");
1558 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1559 PKT_DATA
, ret
+5, 16, PKT_END
);
1562 if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
1563 logevent("Pageant's response accepted");
1564 if (flags
& FLAG_VERBOSE
) {
1565 c_write("Authenticated using RSA key \"",
1567 c_write(commentp
, commentlen
);
1568 c_write("\" from agent\r\n", 14);
1572 logevent("Pageant's response not accepted");
1574 logevent("Pageant failed to answer challenge");
1578 logevent("No reply received from Pageant");
1581 freebn(key
.exponent
);
1582 freebn(key
.modulus
);
1591 if (*cfg
.keyfile
&& !tried_publickey
)
1592 pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
1594 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1596 (supported_auths_mask
& (1<<SSH1_AUTH_TIS
))) {
1597 pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
1598 logevent("Requested TIS authentication");
1599 send_packet(SSH1_CMSG_AUTH_TIS
, PKT_END
);
1601 if (pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
1602 logevent("TIS authentication declined");
1603 if (flags
& FLAG_INTERACTIVE
)
1604 c_write("TIS authentication refused.\r\n", 29);
1606 int challengelen
= ((pktin
.body
[0] << 24) |
1607 (pktin
.body
[1] << 16) |
1608 (pktin
.body
[2] << 8) |
1610 logevent("Received TIS challenge");
1611 if (challengelen
> sizeof(prompt
)-1)
1612 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1613 memcpy(prompt
, pktin
.body
+4, challengelen
);
1614 prompt
[challengelen
] = '\0';
1617 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1619 (supported_auths_mask
& (1<<SSH1_AUTH_CCARD
))) {
1620 pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
1621 logevent("Requested CryptoCard authentication");
1622 send_packet(SSH1_CMSG_AUTH_CCARD
, PKT_END
);
1624 if (pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
1625 logevent("CryptoCard authentication declined");
1626 c_write("CryptoCard authentication refused.\r\n", 29);
1628 int challengelen
= ((pktin
.body
[0] << 24) |
1629 (pktin
.body
[1] << 16) |
1630 (pktin
.body
[2] << 8) |
1632 logevent("Received CryptoCard challenge");
1633 if (challengelen
> sizeof(prompt
)-1)
1634 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1635 memcpy(prompt
, pktin
.body
+4, challengelen
);
1636 strncpy(prompt
+ challengelen
, "\r\nResponse : ",
1637 sizeof(prompt
)-challengelen
);
1638 prompt
[sizeof(prompt
)-1] = '\0';
1641 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
1642 sprintf(prompt
, "%.90s@%.90s's password: ",
1643 username
, savedhost
);
1645 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1646 char *comment
= NULL
;
1647 if (flags
& FLAG_VERBOSE
)
1648 c_write("Trying public key authentication.\r\n", 35);
1649 if (!rsakey_encrypted(cfg
.keyfile
, &comment
)) {
1650 if (flags
& FLAG_VERBOSE
)
1651 c_write("No passphrase required.\r\n", 25);
1654 sprintf(prompt
, "Passphrase for key \"%.100s\": ", comment
);
1658 if (ssh_get_password
) {
1659 if (!ssh_get_password(prompt
, password
, sizeof(password
))) {
1661 * get_password failed to get a password (for
1662 * example because one was supplied on the command
1663 * line which has already failed to work).
1666 logevent("No more passwords to try");
1667 ssh_state
= SSH_STATE_CLOSED
;
1671 c_write(prompt
, strlen(prompt
));
1675 crWaitUntil(!ispkt
);
1676 while (inlen
--) switch (c
= *in
++) {
1693 if (((c
>= ' ' && c
<= '~') ||
1694 ((unsigned char)c
>= 160)) && pos
< sizeof(password
))
1695 password
[pos
++] = c
;
1703 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1705 * Try public key authentication with the specified
1708 static struct RSAKey pubkey
;
1709 static Bignum challenge
, response
;
1711 static unsigned char buffer
[32];
1713 tried_publickey
= 1;
1714 i
= loadrsakey(cfg
.keyfile
, &pubkey
, NULL
, password
);
1716 c_write("Couldn't load public key from ", 30);
1717 c_write(cfg
.keyfile
, strlen(cfg
.keyfile
));
1718 c_write(".\r\n", 3);
1719 continue; /* go and try password */
1722 c_write("Wrong passphrase.\r\n", 19);
1723 tried_publickey
= 0;
1724 continue; /* try again */
1728 * Send a public key attempt.
1730 send_packet(SSH1_CMSG_AUTH_RSA
,
1731 PKT_BIGNUM
, pubkey
.modulus
, PKT_END
);
1734 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1735 c_write("Server refused our public key.\r\n", 32);
1736 continue; /* go and try password */
1738 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1739 bombout(("Bizarre response to offer of public key"));
1742 ssh1_read_bignum(pktin
.body
, &challenge
);
1743 response
= rsadecrypt(challenge
, &pubkey
);
1744 freebn(pubkey
.private_exponent
); /* burn the evidence */
1746 for (i
= 0; i
< 32; i
++) {
1747 buffer
[i
] = bignum_byte(response
, 31-i
);
1751 MD5Update(&md5c
, buffer
, 32);
1752 MD5Update(&md5c
, session_id
, 16);
1753 MD5Final(buffer
, &md5c
);
1755 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1756 PKT_DATA
, buffer
, 16, PKT_END
);
1759 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1760 if (flags
& FLAG_VERBOSE
)
1761 c_write("Failed to authenticate with our public key.\r\n",
1763 continue; /* go and try password */
1764 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1765 bombout(("Bizarre response to RSA authentication response"));
1769 break; /* we're through! */
1771 send_packet(pwpkt_type
, PKT_STR
, password
, PKT_END
);
1773 logevent("Sent password");
1774 memset(password
, 0, strlen(password
));
1776 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1777 if (flags
& FLAG_VERBOSE
)
1778 c_write("Access denied\r\n", 15);
1779 logevent("Authentication refused");
1780 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
1781 logevent("Received disconnect request");
1782 ssh_state
= SSH_STATE_CLOSED
;
1784 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1785 bombout(("Strange packet received, type %d", pktin
.type
));
1790 logevent("Authentication successful");
1795 void sshfwd_close(struct ssh_channel
*c
) {
1797 if (ssh_version
== 1) {
1798 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
, PKT_END
);
1800 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
1801 ssh2_pkt_adduint32(c
->remoteid
);
1805 if (c
->type
== CHAN_X11
) {
1807 logevent("X11 connection terminated");
1812 void sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
) {
1813 if (ssh_version
== 1) {
1814 send_packet(SSH1_MSG_CHANNEL_DATA
,
1815 PKT_INT
, c
->remoteid
,
1820 ssh2_add_channel_data(c
, buf
, len
);
1825 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
) {
1830 while (!do_ssh1_login(in
, inlen
, ispkt
)) {
1833 if (ssh_state
== SSH_STATE_CLOSED
)
1836 if (cfg
.agentfwd
&& agent_exists()) {
1837 logevent("Requesting agent forwarding");
1838 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
1839 do { crReturnV
; } while (!ispkt
);
1840 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1841 bombout(("Protocol confusion"));
1843 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1844 logevent("Agent forwarding refused");
1846 logevent("Agent forwarding enabled");
1847 ssh_agentfwd_enabled
= TRUE
;
1851 if (cfg
.x11_forward
) {
1852 char proto
[20], data
[64];
1853 logevent("Requesting X11 forwarding");
1854 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
1855 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
1856 PKT_STR
, proto
, PKT_STR
, data
,
1859 do { crReturnV
; } while (!ispkt
);
1860 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1861 bombout(("Protocol confusion"));
1863 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1864 logevent("X11 forwarding refused");
1866 logevent("X11 forwarding enabled");
1867 ssh_X11_fwd_enabled
= TRUE
;
1872 send_packet(SSH1_CMSG_REQUEST_PTY
,
1873 PKT_STR
, cfg
.termtype
,
1874 PKT_INT
, rows
, PKT_INT
, cols
,
1875 PKT_INT
, 0, PKT_INT
, 0,
1878 ssh_state
= SSH_STATE_INTERMED
;
1879 do { crReturnV
; } while (!ispkt
);
1880 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1881 bombout(("Protocol confusion"));
1883 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1884 c_write("Server refused to allocate pty\r\n", 32);
1885 ssh_editing
= ssh_echoing
= 1;
1887 logevent("Allocated pty");
1889 ssh_editing
= ssh_echoing
= 1;
1892 if (cfg
.compression
) {
1893 send_packet(SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
1894 do { crReturnV
; } while (!ispkt
);
1895 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1896 bombout(("Protocol confusion"));
1898 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1899 c_write("Server refused to compress\r\n", 32);
1901 logevent("Started compression");
1902 ssh1_compressing
= TRUE
;
1903 zlib_compress_init();
1904 zlib_decompress_init();
1907 if (*cfg
.remote_cmd
)
1908 send_packet(SSH1_CMSG_EXEC_CMD
, PKT_STR
, cfg
.remote_cmd
, PKT_END
);
1910 send_packet(SSH1_CMSG_EXEC_SHELL
, PKT_END
);
1911 logevent("Started session");
1913 ssh_state
= SSH_STATE_SESSION
;
1917 ssh_special(TS_EOF
);
1919 ldisc_send(NULL
, 0); /* cause ldisc to notice changes */
1921 ssh_channels
= newtree234(ssh_channelcmp
);
1925 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
1926 pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
1927 long len
= GET_32BIT(pktin
.body
);
1928 from_backend(pktin
.type
== SSH1_SMSG_STDERR_DATA
,
1930 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
1931 ssh_state
= SSH_STATE_CLOSED
;
1932 logevent("Received disconnect request");
1934 } else if (pktin
.type
== SSH1_SMSG_X11_OPEN
) {
1935 /* Remote side is trying to open a channel to talk to our
1936 * X-Server. Give them back a local channel number. */
1938 struct ssh_channel
*c
, *d
;
1941 logevent("Received X11 connect request");
1942 /* Refuse if X11 forwarding is disabled. */
1943 if (!ssh_X11_fwd_enabled
) {
1944 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
1945 PKT_INT
, GET_32BIT(pktin
.body
),
1947 logevent("Rejected X11 connect request");
1949 c
= smalloc(sizeof(struct ssh_channel
));
1951 if ( x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
1952 logevent("opening X11 forward connection failed");
1954 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
1955 PKT_INT
, GET_32BIT(pktin
.body
),
1958 logevent("opening X11 forward connection succeeded");
1959 for (i
=1, d
= first234(ssh_channels
, &e
); d
; d
= next234(&e
)) {
1961 break; /* found a free number */
1964 c
->remoteid
= GET_32BIT(pktin
.body
);
1967 c
->type
= CHAN_X11
; /* identify channel type */
1968 add234(ssh_channels
, c
);
1969 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
1970 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
1972 logevent("Opened X11 forward channel");
1975 } else if (pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
1976 /* Remote side is trying to open a channel to talk to our
1977 * agent. Give them back a local channel number. */
1979 struct ssh_channel
*c
;
1982 /* Refuse if agent forwarding is disabled. */
1983 if (!ssh_agentfwd_enabled
) {
1984 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
1985 PKT_INT
, GET_32BIT(pktin
.body
),
1989 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
)) {
1991 break; /* found a free number */
1994 c
= smalloc(sizeof(struct ssh_channel
));
1995 c
->remoteid
= GET_32BIT(pktin
.body
);
1998 c
->type
= CHAN_AGENT
; /* identify channel type */
1999 c
->u
.a
.lensofar
= 0;
2000 add234(ssh_channels
, c
);
2001 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
2002 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
2005 } else if (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
2006 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
2007 /* Remote side closes a channel. */
2008 unsigned i
= GET_32BIT(pktin
.body
);
2009 struct ssh_channel
*c
;
2010 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2013 closetype
= (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
2014 send_packet(pktin
.type
, PKT_INT
, c
->remoteid
, PKT_END
);
2015 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
2016 logevent("X11 connection closed");
2017 assert(c
->u
.x11
.s
!= NULL
);
2018 x11_close(c
->u
.x11
.s
);
2021 c
->closes
|= closetype
;
2022 if (c
->closes
== 3) {
2023 del234(ssh_channels
, c
);
2027 } else if (pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
2028 /* Data sent down one of our channels. */
2029 int i
= GET_32BIT(pktin
.body
);
2030 int len
= GET_32BIT(pktin
.body
+4);
2031 unsigned char *p
= pktin
.body
+8;
2032 struct ssh_channel
*c
;
2033 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2037 x11_send(c
->u
.x11
.s
, p
, len
);
2040 /* Data for an agent message. Buffer it. */
2042 if (c
->u
.a
.lensofar
< 4) {
2043 int l
= min(4 - c
->u
.a
.lensofar
, len
);
2044 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
, l
);
2045 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
2047 if (c
->u
.a
.lensofar
== 4) {
2048 c
->u
.a
.totallen
= 4 + GET_32BIT(c
->u
.a
.msglen
);
2049 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
2050 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
2052 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
2053 int l
= min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
, len
);
2054 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
, l
);
2055 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
2057 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
2058 void *reply
, *sentreply
;
2060 agent_query(c
->u
.a
.message
, c
->u
.a
.totallen
,
2065 /* Fake SSH_AGENT_FAILURE. */
2066 sentreply
= "\0\0\0\1\5";
2069 send_packet(SSH1_MSG_CHANNEL_DATA
,
2070 PKT_INT
, c
->remoteid
,
2072 PKT_DATA
, sentreply
, replylen
,
2076 sfree(c
->u
.a
.message
);
2077 c
->u
.a
.lensofar
= 0;
2083 } else if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
2084 /* may be from EXEC_SHELL on some servers */
2085 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2086 /* may be from EXEC_SHELL on some servers
2087 * if no pty is available or in other odd cases. Ignore */
2088 } else if (pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
2089 send_packet(SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
2091 bombout(("Strange packet received: type %d", pktin
.type
));
2096 int len
= min(inlen
, 512);
2097 send_packet(SSH1_CMSG_STDIN_DATA
,
2098 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
2109 * Utility routine for decoding comma-separated strings in KEXINIT.
2111 static int in_commasep_string(char *needle
, char *haystack
, int haylen
) {
2112 int needlen
= strlen(needle
);
2115 * Is it at the start of the string?
2117 if (haylen
>= needlen
&& /* haystack is long enough */
2118 !memcmp(needle
, haystack
, needlen
) && /* initial match */
2119 (haylen
== needlen
|| haystack
[needlen
] == ',')
2120 /* either , or EOS follows */
2124 * If not, search for the next comma and resume after that.
2125 * If no comma found, terminate.
2127 while (haylen
> 0 && *haystack
!= ',')
2128 haylen
--, haystack
++;
2131 haylen
--, haystack
++; /* skip over comma itself */
2136 * SSH2 key creation method.
2138 static void ssh2_mkkey(Bignum K
, char *H
, char *sessid
, char chr
, char *keyspace
) {
2140 /* First 20 bytes. */
2143 SHA_Bytes(&s
, H
, 20);
2144 SHA_Bytes(&s
, &chr
, 1);
2145 SHA_Bytes(&s
, sessid
, 20);
2146 SHA_Final(&s
, keyspace
);
2147 /* Next 20 bytes. */
2150 SHA_Bytes(&s
, H
, 20);
2151 SHA_Bytes(&s
, keyspace
, 20);
2152 SHA_Final(&s
, keyspace
+20);
2156 * Handle the SSH2 transport layer.
2158 static int do_ssh2_transport(unsigned char *in
, int inlen
, int ispkt
)
2162 static Bignum e
, f
, K
;
2163 static const struct ssh_mac
**maclist
;
2165 static const struct ssh_cipher
*cscipher_tobe
= NULL
;
2166 static const struct ssh_cipher
*sccipher_tobe
= NULL
;
2167 static const struct ssh_mac
*csmac_tobe
= NULL
;
2168 static const struct ssh_mac
*scmac_tobe
= NULL
;
2169 static const struct ssh_compress
*cscomp_tobe
= NULL
;
2170 static const struct ssh_compress
*sccomp_tobe
= NULL
;
2171 static char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
2172 static int hostkeylen
, siglen
;
2173 static void *hkey
; /* actual host key */
2174 static unsigned char exchange_hash
[20];
2175 static unsigned char first_exchange_hash
[20];
2176 static unsigned char keyspace
[40];
2177 static const struct ssh_cipher
*preferred_cipher
;
2178 static const struct ssh_compress
*preferred_comp
;
2179 static int first_kex
;
2186 * Set up the preferred cipher and compression.
2188 if (cfg
.cipher
== CIPHER_BLOWFISH
) {
2189 preferred_cipher
= &ssh_blowfish_ssh2
;
2190 } else if (cfg
.cipher
== CIPHER_DES
) {
2191 logevent("Single DES not supported in SSH2; using 3DES");
2192 preferred_cipher
= &ssh_3des_ssh2
;
2193 } else if (cfg
.cipher
== CIPHER_3DES
) {
2194 preferred_cipher
= &ssh_3des_ssh2
;
2196 /* Shouldn't happen, but we do want to initialise to _something_. */
2197 preferred_cipher
= &ssh_3des_ssh2
;
2199 if (cfg
.compression
)
2200 preferred_comp
= &ssh_zlib
;
2202 preferred_comp
= &ssh_comp_none
;
2205 * Be prepared to work around the buggy MAC problem.
2208 maclist
= buggymacs
, nmacs
= lenof(buggymacs
);
2210 maclist
= macs
, nmacs
= lenof(macs
);
2214 * Construct and send our key exchange packet.
2216 ssh2_pkt_init(SSH2_MSG_KEXINIT
);
2217 for (i
= 0; i
< 16; i
++)
2218 ssh2_pkt_addbyte((unsigned char)random_byte());
2219 /* List key exchange algorithms. */
2220 ssh2_pkt_addstring_start();
2221 for (i
= 0; i
< lenof(kex_algs
); i
++) {
2222 ssh2_pkt_addstring_str(kex_algs
[i
]->name
);
2223 if (i
< lenof(kex_algs
)-1)
2224 ssh2_pkt_addstring_str(",");
2226 /* List server host key algorithms. */
2227 ssh2_pkt_addstring_start();
2228 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
2229 ssh2_pkt_addstring_str(hostkey_algs
[i
]->name
);
2230 if (i
< lenof(hostkey_algs
)-1)
2231 ssh2_pkt_addstring_str(",");
2233 /* List client->server encryption algorithms. */
2234 ssh2_pkt_addstring_start();
2235 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2236 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2237 ssh2_pkt_addstring_str(c
->name
);
2238 if (i
< lenof(ciphers
))
2239 ssh2_pkt_addstring_str(",");
2241 /* List server->client encryption algorithms. */
2242 ssh2_pkt_addstring_start();
2243 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2244 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2245 ssh2_pkt_addstring_str(c
->name
);
2246 if (i
< lenof(ciphers
))
2247 ssh2_pkt_addstring_str(",");
2249 /* List client->server MAC algorithms. */
2250 ssh2_pkt_addstring_start();
2251 for (i
= 0; i
< nmacs
; i
++) {
2252 ssh2_pkt_addstring_str(maclist
[i
]->name
);
2254 ssh2_pkt_addstring_str(",");
2256 /* List server->client MAC algorithms. */
2257 ssh2_pkt_addstring_start();
2258 for (i
= 0; i
< nmacs
; i
++) {
2259 ssh2_pkt_addstring_str(maclist
[i
]->name
);
2261 ssh2_pkt_addstring_str(",");
2263 /* List client->server compression algorithms. */
2264 ssh2_pkt_addstring_start();
2265 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2266 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2267 ssh2_pkt_addstring_str(c
->name
);
2268 if (i
< lenof(compressions
))
2269 ssh2_pkt_addstring_str(",");
2271 /* List server->client compression algorithms. */
2272 ssh2_pkt_addstring_start();
2273 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2274 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2275 ssh2_pkt_addstring_str(c
->name
);
2276 if (i
< lenof(compressions
))
2277 ssh2_pkt_addstring_str(",");
2279 /* List client->server languages. Empty list. */
2280 ssh2_pkt_addstring_start();
2281 /* List server->client languages. Empty list. */
2282 ssh2_pkt_addstring_start();
2283 /* First KEX packet does _not_ follow, because we're not that brave. */
2284 ssh2_pkt_addbool(FALSE
);
2286 ssh2_pkt_adduint32(0);
2288 exhash
= exhashbase
;
2289 sha_string(&exhash
, pktout
.data
+5, pktout
.length
-5);
2293 if (!ispkt
) crWaitUntil(ispkt
);
2294 sha_string(&exhash
, pktin
.data
+5, pktin
.length
-5);
2297 * Now examine the other side's KEXINIT to see what we're up
2300 if (pktin
.type
!= SSH2_MSG_KEXINIT
) {
2301 bombout(("expected key exchange packet from server"));
2304 kex
= NULL
; hostkey
= NULL
; cscipher_tobe
= NULL
; sccipher_tobe
= NULL
;
2305 csmac_tobe
= NULL
; scmac_tobe
= NULL
; cscomp_tobe
= NULL
; sccomp_tobe
= NULL
;
2306 pktin
.savedpos
+= 16; /* skip garbage cookie */
2307 ssh2_pkt_getstring(&str
, &len
); /* key exchange algorithms */
2308 for (i
= 0; i
< lenof(kex_algs
); i
++) {
2309 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
2314 ssh2_pkt_getstring(&str
, &len
); /* host key algorithms */
2315 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
2316 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
2317 hostkey
= hostkey_algs
[i
];
2321 ssh2_pkt_getstring(&str
, &len
); /* client->server cipher */
2322 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2323 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2324 if (in_commasep_string(c
->name
, str
, len
)) {
2329 ssh2_pkt_getstring(&str
, &len
); /* server->client cipher */
2330 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2331 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2332 if (in_commasep_string(c
->name
, str
, len
)) {
2337 ssh2_pkt_getstring(&str
, &len
); /* client->server mac */
2338 for (i
= 0; i
< nmacs
; i
++) {
2339 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2340 csmac_tobe
= maclist
[i
];
2344 ssh2_pkt_getstring(&str
, &len
); /* server->client mac */
2345 for (i
= 0; i
< nmacs
; i
++) {
2346 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2347 scmac_tobe
= maclist
[i
];
2351 ssh2_pkt_getstring(&str
, &len
); /* client->server compression */
2352 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2353 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2354 if (in_commasep_string(c
->name
, str
, len
)) {
2359 ssh2_pkt_getstring(&str
, &len
); /* server->client compression */
2360 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2361 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2362 if (in_commasep_string(c
->name
, str
, len
)) {
2369 * Currently we only support Diffie-Hellman and DSS, so let's
2370 * bomb out if those aren't selected.
2372 if (kex
!= &ssh_diffiehellman
|| hostkey
!= &ssh_dss
) {
2373 bombout(("internal fault: chaos in SSH 2 transport layer"));
2378 * Now we begin the fun. Generate and send e for Diffie-Hellman.
2383 ssh2_pkt_init(SSH2_MSG_KEXDH_INIT
);
2388 if (pktin
.type
!= SSH2_MSG_KEXDH_REPLY
) {
2389 bombout(("expected key exchange packet from server"));
2392 ssh2_pkt_getstring(&hostkeydata
, &hostkeylen
);
2393 f
= ssh2_pkt_getmp();
2394 ssh2_pkt_getstring(&sigdata
, &siglen
);
2398 sha_string(&exhash
, hostkeydata
, hostkeylen
);
2399 sha_mpint(&exhash
, e
);
2400 sha_mpint(&exhash
, f
);
2401 sha_mpint(&exhash
, K
);
2402 SHA_Final(&exhash
, exchange_hash
);
2407 debug(("Exchange hash is:\r\n"));
2408 for (i
= 0; i
< 20; i
++)
2409 debug((" %02x", exchange_hash
[i
]));
2413 hkey
= hostkey
->newkey(hostkeydata
, hostkeylen
);
2414 if (!hostkey
->verifysig(hkey
, sigdata
, siglen
, exchange_hash
, 20)) {
2415 bombout(("Server failed host key check"));
2420 * Expect SSH2_MSG_NEWKEYS from server.
2423 if (pktin
.type
!= SSH2_MSG_NEWKEYS
) {
2424 bombout(("expected new-keys packet from server"));
2429 * Authenticate remote host: verify host key. (We've already
2430 * checked the signature of the exchange hash.)
2432 keystr
= hostkey
->fmtkey(hkey
);
2433 fingerprint
= hostkey
->fingerprint(hkey
);
2434 verify_ssh_host_key(savedhost
, savedport
, hostkey
->keytype
,
2435 keystr
, fingerprint
);
2436 if (first_kex
) { /* don't bother logging this in rekeys */
2437 logevent("Host key fingerprint is:");
2438 logevent(fingerprint
);
2442 hostkey
->freekey(hkey
);
2445 * Send SSH2_MSG_NEWKEYS.
2447 ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
2451 * Create and initialise session keys.
2453 cscipher
= cscipher_tobe
;
2454 sccipher
= sccipher_tobe
;
2457 cscomp
= cscomp_tobe
;
2458 sccomp
= sccomp_tobe
;
2459 cscomp
->compress_init();
2460 sccomp
->decompress_init();
2462 * Set IVs after keys. Here we use the exchange hash from the
2463 * _first_ key exchange.
2466 memcpy(first_exchange_hash
, exchange_hash
, sizeof(exchange_hash
));
2467 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'C', keyspace
);
2468 cscipher
->setcskey(keyspace
);
2469 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'D', keyspace
);
2470 sccipher
->setsckey(keyspace
);
2471 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'A', keyspace
);
2472 cscipher
->setcsiv(keyspace
);
2473 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'B', keyspace
);
2474 sccipher
->setsciv(keyspace
);
2475 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'E', keyspace
);
2476 csmac
->setcskey(keyspace
);
2477 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'F', keyspace
);
2478 scmac
->setsckey(keyspace
);
2481 * If this is the first key exchange phase, we must pass the
2482 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
2483 * wants to see it but because it will need time to initialise
2484 * itself before it sees an actual packet. In subsequent key
2485 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
2486 * it would only confuse the layer above.
2494 * Now we're encrypting. Begin returning 1 to the protocol main
2495 * function so that other things can run on top of the
2496 * transport. If we ever see a KEXINIT, we must go back to the
2499 while (!(ispkt
&& pktin
.type
== SSH2_MSG_KEXINIT
)) {
2502 logevent("Server initiated key re-exchange");
2503 goto begin_key_exchange
;
2509 * Add data to an SSH2 channel output buffer.
2511 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
) {
2512 if (c
->v2
.outbufsize
<
2513 c
->v2
.outbuflen
+ len
) {
2515 c
->v2
.outbuflen
+ len
+ 1024;
2516 c
->v2
.outbuffer
= srealloc(c
->v2
.outbuffer
,
2519 memcpy(c
->v2
.outbuffer
+ c
->v2
.outbuflen
,
2521 c
->v2
.outbuflen
+= len
;
2525 * Attempt to send data on an SSH2 channel.
2527 static void ssh2_try_send(struct ssh_channel
*c
) {
2528 while (c
->v2
.remwindow
> 0 &&
2529 c
->v2
.outbuflen
> 0) {
2530 unsigned len
= c
->v2
.remwindow
;
2531 if (len
> c
->v2
.outbuflen
)
2532 len
= c
->v2
.outbuflen
;
2533 if (len
> c
->v2
.remmaxpkt
)
2534 len
= c
->v2
.remmaxpkt
;
2535 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
2536 ssh2_pkt_adduint32(c
->remoteid
);
2537 ssh2_pkt_addstring_start();
2538 ssh2_pkt_addstring_data(c
->v2
.outbuffer
, len
);
2540 c
->v2
.outbuflen
-= len
;
2541 memmove(c
->v2
.outbuffer
, c
->v2
.outbuffer
+len
,
2543 c
->v2
.remwindow
-= len
;
2548 * Handle the SSH2 userauth and connection layers.
2550 static void do_ssh2_authconn(unsigned char *in
, int inlen
, int ispkt
)
2552 static unsigned long remote_winsize
;
2553 static unsigned long remote_maxpkt
;
2558 * Request userauth protocol, and await a response to it.
2560 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
2561 ssh2_pkt_addstring("ssh-userauth");
2563 crWaitUntilV(ispkt
);
2564 if (pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
2565 bombout(("Server refused user authentication protocol"));
2570 * FIXME: currently we support only password authentication.
2571 * (This places us technically in violation of the SSH2 spec.
2572 * We must fix this.)
2576 * Get a username and a password.
2578 static char username
[100];
2579 static char password
[100];
2583 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
2584 c_write("login as: ", 10);
2587 crWaitUntilV(!ispkt
);
2588 while (inlen
--) switch (c
= *in
++) {
2595 c_write("\b \b", 3);
2601 c_write("\b \b", 3);
2610 if (((c
>= ' ' && c
<= '~') ||
2611 ((unsigned char)c
>= 160)) && pos
< 40) {
2612 username
[pos
++] = c
;
2619 username
[strcspn(username
, "\n\r")] = '\0';
2622 strncpy(username
, cfg
.username
, 99);
2623 username
[99] = '\0';
2624 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
2625 sprintf(stuff
, "Using username \"%s\".\r\n", username
);
2626 c_write(stuff
, strlen(stuff
));
2630 if (ssh_get_password
) {
2632 sprintf(prompt
, "%.90s@%.90s's password: ", username
, savedhost
);
2633 if (!ssh_get_password(prompt
, password
, sizeof(password
))) {
2635 * get_password failed to get a password (for
2636 * example because one was supplied on the command
2637 * line which has already failed to work).
2640 logevent("No more passwords to try");
2641 ssh_state
= SSH_STATE_CLOSED
;
2645 c_write("password: ", 10);
2650 crWaitUntilV(!ispkt
);
2651 while (inlen
--) switch (c
= *in
++) {
2668 if (((c
>= ' ' && c
<= '~') ||
2669 ((unsigned char)c
>= 160)) && pos
< 40)
2670 password
[pos
++] = c
;
2678 * We send the password packet lumped tightly together with
2679 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
2680 * string long enough to make the total length of the two
2681 * packets constant. This should ensure that a passive
2682 * listener doing traffic analyis can't work out the length
2685 * For this to work, we need an assumption about the
2686 * maximum length of the password packet. I think 256 is
2687 * pretty conservative. Anyone using a password longer than
2688 * that probably doesn't have much to worry about from
2689 * people who find out how long their password is!
2691 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
2692 ssh2_pkt_addstring(username
);
2693 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2694 ssh2_pkt_addstring("password");
2695 ssh2_pkt_addbool(FALSE
);
2696 ssh2_pkt_addstring(password
);
2699 * We'll include a string that's an exact multiple of the
2700 * cipher block size. If the cipher is NULL for some
2701 * reason, we don't do this trick at all because we gain
2706 ssh2_pkt_init(SSH2_MSG_IGNORE
);
2707 ssh2_pkt_addstring_start();
2708 for (i
= deferred_len
; i
<= 256; i
+= cscipher
->blksize
) {
2709 for (j
= 0; j
< cscipher
->blksize
; j
++) {
2710 char c
= (char)random_byte();
2711 ssh2_pkt_addstring_data(&c
, 1);
2716 ssh2_pkt_defersend();
2718 crWaitUntilV(ispkt
);
2719 if (pktin
.type
!= SSH2_MSG_USERAUTH_SUCCESS
) {
2720 c_write("Access denied\r\n", 15);
2721 logevent("Authentication refused");
2727 * Now we're authenticated for the connection protocol. The
2728 * connection protocol will automatically have started at this
2729 * point; there's no need to send SERVICE_REQUEST.
2733 * So now create a channel with a session in it.
2735 mainchan
= smalloc(sizeof(struct ssh_channel
));
2736 mainchan
->localid
= 100; /* as good as any */
2737 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
2738 ssh2_pkt_addstring("session");
2739 ssh2_pkt_adduint32(mainchan
->localid
);
2740 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
2741 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
2743 crWaitUntilV(ispkt
);
2744 if (pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
2745 bombout(("Server refused to open a session"));
2747 /* FIXME: error data comes back in FAILURE packet */
2749 if (ssh2_pkt_getuint32() != mainchan
->localid
) {
2750 bombout(("Server's channel confirmation cited wrong channel"));
2753 mainchan
->remoteid
= ssh2_pkt_getuint32();
2754 mainchan
->type
= CHAN_MAINSESSION
;
2755 mainchan
->closes
= 0;
2756 mainchan
->v2
.remwindow
= ssh2_pkt_getuint32();
2757 mainchan
->v2
.remmaxpkt
= ssh2_pkt_getuint32();
2758 mainchan
->v2
.outbuffer
= NULL
;
2759 mainchan
->v2
.outbuflen
= mainchan
->v2
.outbufsize
= 0;
2760 ssh_channels
= newtree234(ssh_channelcmp
);
2761 add234(ssh_channels
, mainchan
);
2762 logevent("Opened channel for session");
2765 * Potentially enable X11 forwarding.
2767 if (cfg
.x11_forward
) {
2768 char proto
[20], data
[64];
2769 logevent("Requesting X11 forwarding");
2770 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
2771 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2772 ssh2_pkt_adduint32(mainchan
->remoteid
);
2773 ssh2_pkt_addstring("x11-req");
2774 ssh2_pkt_addbool(1); /* want reply */
2775 ssh2_pkt_addbool(0); /* many connections */
2776 ssh2_pkt_addstring(proto
);
2777 ssh2_pkt_addstring(data
);
2778 ssh2_pkt_adduint32(0); /* screen number */
2782 crWaitUntilV(ispkt
);
2783 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2784 unsigned i
= ssh2_pkt_getuint32();
2785 struct ssh_channel
*c
;
2786 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2788 continue; /* nonexistent channel */
2789 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2791 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2793 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2794 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2795 bombout(("Server got confused by X11 forwarding request"));
2798 logevent("X11 forwarding refused");
2800 logevent("X11 forwarding enabled");
2801 ssh_X11_fwd_enabled
= TRUE
;
2806 * Now allocate a pty for the session.
2809 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2810 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
2811 ssh2_pkt_addstring("pty-req");
2812 ssh2_pkt_addbool(1); /* want reply */
2813 ssh2_pkt_addstring(cfg
.termtype
);
2814 ssh2_pkt_adduint32(cols
);
2815 ssh2_pkt_adduint32(rows
);
2816 ssh2_pkt_adduint32(0); /* pixel width */
2817 ssh2_pkt_adduint32(0); /* pixel height */
2818 ssh2_pkt_addstring_start();
2819 ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
2821 ssh_state
= SSH_STATE_INTERMED
;
2824 crWaitUntilV(ispkt
);
2825 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2826 unsigned i
= ssh2_pkt_getuint32();
2827 struct ssh_channel
*c
;
2828 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2830 continue; /* nonexistent channel */
2831 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2833 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2835 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2836 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2837 bombout(("Server got confused by pty request"));
2840 c_write("Server refused to allocate pty\r\n", 32);
2841 ssh_editing
= ssh_echoing
= 1;
2843 logevent("Allocated pty");
2846 ssh_editing
= ssh_echoing
= 1;
2850 * Start a shell or a remote command.
2852 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2853 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
2854 if (cfg
.ssh_subsys
) {
2855 ssh2_pkt_addstring("subsystem");
2856 ssh2_pkt_addbool(1); /* want reply */
2857 ssh2_pkt_addstring(cfg
.remote_cmd
);
2858 } else if (*cfg
.remote_cmd
) {
2859 ssh2_pkt_addstring("exec");
2860 ssh2_pkt_addbool(1); /* want reply */
2861 ssh2_pkt_addstring(cfg
.remote_cmd
);
2863 ssh2_pkt_addstring("shell");
2864 ssh2_pkt_addbool(1); /* want reply */
2868 crWaitUntilV(ispkt
);
2869 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2870 unsigned i
= ssh2_pkt_getuint32();
2871 struct ssh_channel
*c
;
2872 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2874 continue; /* nonexistent channel */
2875 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2877 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2878 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2879 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2880 bombout(("Server got confused by shell/command request"));
2883 bombout(("Server refused to start a shell/command"));
2886 logevent("Started a shell/command");
2889 ssh_state
= SSH_STATE_SESSION
;
2893 ssh_special(TS_EOF
);
2898 ldisc_send(NULL
, 0); /* cause ldisc to notice changes */
2901 static int try_send
;
2905 if (pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
2906 pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
2909 unsigned i
= ssh2_pkt_getuint32();
2910 struct ssh_channel
*c
;
2911 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2913 continue; /* nonexistent channel */
2914 if (pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
2915 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR
)
2916 continue; /* extended but not stderr */
2917 ssh2_pkt_getstring(&data
, &length
);
2920 case CHAN_MAINSESSION
:
2921 from_backend(pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
,
2925 x11_send(c
->u
.x11
.s
, data
, length
);
2929 * Enlarge the window again at the remote
2930 * side, just in case it ever runs down and
2931 * they fail to send us any more data.
2933 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2934 ssh2_pkt_adduint32(c
->remoteid
);
2935 ssh2_pkt_adduint32(length
);
2938 } else if (pktin
.type
== SSH2_MSG_DISCONNECT
) {
2939 ssh_state
= SSH_STATE_CLOSED
;
2940 logevent("Received disconnect message");
2942 } else if (pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
2943 continue; /* exit status et al; ignore (FIXME?) */
2944 } else if (pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
2945 unsigned i
= ssh2_pkt_getuint32();
2946 struct ssh_channel
*c
;
2948 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2950 continue; /* nonexistent channel */
2952 if (c
->type
== CHAN_X11
) {
2954 * Remote EOF on an X11 channel means we should
2955 * wrap up and close the channel ourselves.
2957 x11_close(c
->u
.x11
.s
);
2960 } else if (pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
2961 unsigned i
= ssh2_pkt_getuint32();
2962 struct ssh_channel
*c
;
2965 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2967 continue; /* nonexistent channel */
2968 if (c
->closes
== 0) {
2969 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
2970 ssh2_pkt_adduint32(c
->remoteid
);
2973 /* Do pre-close processing on the channel. */
2975 case CHAN_MAINSESSION
:
2976 break; /* nothing to see here, move along */
2980 del234(ssh_channels
, c
);
2981 sfree(c
->v2
.outbuffer
);
2985 * See if that was the last channel left open.
2987 c
= first234(ssh_channels
, &e
);
2989 logevent("All channels closed. Disconnecting");
2990 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
2991 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
2992 ssh2_pkt_addstring("All open channels closed");
2993 ssh2_pkt_addstring("en"); /* language tag */
2995 ssh_state
= SSH_STATE_CLOSED
;
2998 continue; /* remote sends close; ignore (FIXME) */
2999 } else if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
3000 unsigned i
= ssh2_pkt_getuint32();
3001 struct ssh_channel
*c
;
3002 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3004 continue; /* nonexistent channel */
3005 mainchan
->v2
.remwindow
+= ssh2_pkt_getuint32();
3007 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
3011 struct ssh_channel
*c
;
3012 ssh2_pkt_getstring(&type
, &typelen
);
3013 c
= smalloc(sizeof(struct ssh_channel
));
3015 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
3016 if (!ssh_X11_fwd_enabled
)
3017 error
= "X11 forwarding is not enabled";
3018 else if ( x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
3019 error
= "Unable to open an X11 connection";
3024 error
= "Unsupported channel type requested";
3027 c
->remoteid
= ssh2_pkt_getuint32();
3029 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
3030 ssh2_pkt_adduint32(c
->remoteid
);
3031 ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED
);
3032 ssh2_pkt_addstring(error
);
3033 ssh2_pkt_addstring("en"); /* language tag */
3037 struct ssh_channel
*d
;
3041 for (i
=1, d
= first234(ssh_channels
, &e
); d
;
3044 break; /* found a free number */
3049 c
->v2
.remwindow
= ssh2_pkt_getuint32();
3050 c
->v2
.remmaxpkt
= ssh2_pkt_getuint32();
3051 c
->v2
.outbuffer
= NULL
;
3052 c
->v2
.outbuflen
= c
->v2
.outbufsize
= 0;
3053 add234(ssh_channels
, c
);
3054 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
3055 ssh2_pkt_adduint32(c
->remoteid
);
3056 ssh2_pkt_adduint32(c
->localid
);
3057 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
3058 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
3062 bombout(("Strange packet received: type %d", pktin
.type
));
3067 * We have spare data. Add it to the channel buffer.
3069 ssh2_add_channel_data(mainchan
, in
, inlen
);
3074 struct ssh_channel
*c
;
3076 * Try to send data on all channels if we can.
3078 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
))
3087 * Handle the top-level SSH2 protocol.
3089 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
)
3091 if (do_ssh2_transport(in
, inlen
, ispkt
) == 0)
3093 do_ssh2_authconn(in
, inlen
, ispkt
);
3097 * Called to set up the connection.
3099 * Returns an error message, or NULL on success.
3101 static char *ssh_init (char *host
, int port
, char **realhost
) {
3105 if(crypto_startup() == 0)
3106 return "Microsoft high encryption pack not installed!";
3113 p
= connect_to_host(host
, port
, realhost
);
3121 * Called to send data down the Telnet connection.
3123 static void ssh_send (char *buf
, int len
) {
3124 if (s
== NULL
|| ssh_protocol
== NULL
)
3127 ssh_protocol(buf
, len
, 0);
3131 * Called to set the size of the window from SSH's POV.
3133 static void ssh_size(void) {
3134 switch (ssh_state
) {
3135 case SSH_STATE_BEFORE_SIZE
:
3136 case SSH_STATE_PREPACKET
:
3137 case SSH_STATE_CLOSED
:
3138 break; /* do nothing */
3139 case SSH_STATE_INTERMED
:
3140 size_needed
= TRUE
; /* buffer for later */
3142 case SSH_STATE_SESSION
:
3144 if (ssh_version
== 1) {
3145 send_packet(SSH1_CMSG_WINDOW_SIZE
,
3146 PKT_INT
, rows
, PKT_INT
, cols
,
3147 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
3149 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
3150 ssh2_pkt_adduint32(mainchan
->remoteid
);
3151 ssh2_pkt_addstring("window-change");
3152 ssh2_pkt_addbool(0);
3153 ssh2_pkt_adduint32(cols
);
3154 ssh2_pkt_adduint32(rows
);
3155 ssh2_pkt_adduint32(0);
3156 ssh2_pkt_adduint32(0);
3165 * Send Telnet special codes. TS_EOF is useful for `plink', so you
3166 * can send an EOF and collect resulting output (e.g. `plink
3169 static void ssh_special (Telnet_Special code
) {
3170 if (code
== TS_EOF
) {
3171 if (ssh_state
!= SSH_STATE_SESSION
) {
3173 * Buffer the EOF in case we are pre-SESSION, so we can
3174 * send it as soon as we reach SESSION.
3180 if (ssh_version
== 1) {
3181 send_packet(SSH1_CMSG_EOF
, PKT_END
);
3183 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
3184 ssh2_pkt_adduint32(mainchan
->remoteid
);
3187 logevent("Sent EOF message");
3188 } else if (code
== TS_PING
) {
3189 if (ssh_state
== SSH_STATE_CLOSED
|| ssh_state
== SSH_STATE_PREPACKET
)
3191 if (ssh_version
== 1) {
3192 send_packet(SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
3194 ssh2_pkt_init(SSH2_MSG_IGNORE
);
3195 ssh2_pkt_addstring_start();
3203 static Socket
ssh_socket(void) { return s
; }
3205 static int ssh_sendok(void) { return ssh_send_ok
; }
3207 static int ssh_ldisc(int option
) {
3208 if (option
== LD_ECHO
) return ssh_echoing
;
3209 if (option
== LD_EDIT
) return ssh_editing
;
3213 Backend ssh_backend
= {