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_KEX_DH_GEX_REQUEST 30 /* 0x1e */
91 #define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
92 #define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
93 #define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
94 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
95 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
96 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
97 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
98 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
99 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
100 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
101 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
102 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
103 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
104 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
105 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
106 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
107 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
108 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
109 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
110 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
111 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
112 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
113 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
115 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
116 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
117 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
118 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
119 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
120 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
121 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
122 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
123 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
124 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
125 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
127 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
128 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
129 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
130 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
132 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
134 #define GET_32BIT(cp) \
135 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
136 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
137 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
138 ((unsigned long)(unsigned char)(cp)[3]))
140 #define PUT_32BIT(cp, value) { \
141 (cp)[0] = (unsigned char)((value) >> 24); \
142 (cp)[1] = (unsigned char)((value) >> 16); \
143 (cp)[2] = (unsigned char)((value) >> 8); \
144 (cp)[3] = (unsigned char)(value); }
146 enum { PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
};
148 /* Coroutine mechanics for the sillier bits of the code */
149 #define crBegin1 static int crLine = 0;
150 #define crBegin2 switch(crLine) { case 0:;
151 #define crBegin crBegin1; crBegin2;
152 #define crFinish(z) } crLine = 0; return (z)
153 #define crFinishV } crLine = 0; return
154 #define crReturn(z) \
156 crLine=__LINE__; return (z); case __LINE__:;\
160 crLine=__LINE__; return; case __LINE__:;\
162 #define crStop(z) do{ crLine = 0; return (z); }while(0)
163 #define crStopV do{ crLine = 0; return; }while(0)
164 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
165 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
167 extern const struct ssh_cipher ssh_3des
;
168 extern const struct ssh2_ciphers ssh2_3des
;
169 extern const struct ssh_cipher ssh_des
;
170 extern const struct ssh2_ciphers ssh2_aes
;
171 extern const struct ssh_cipher ssh_blowfish_ssh1
;
172 extern const struct ssh2_ciphers ssh2_blowfish
;
174 extern char *x11_init (Socket
*, char *, void *);
175 extern void x11_close (Socket
);
176 extern void x11_send (Socket
, char *, int);
177 extern void x11_invent_auth(char *, int, char *, int);
180 * Ciphers for SSH2. We miss out single-DES because it isn't
181 * supported; also 3DES and Blowfish are both done differently from
182 * SSH1. (3DES uses outer chaining; Blowfish has the opposite
183 * endianness and different-sized keys.)
185 const static struct ssh2_ciphers
*ciphers
[] = {
191 extern const struct ssh_kex ssh_diffiehellman
;
192 extern const struct ssh_kex ssh_diffiehellman_gex
;
193 const static struct ssh_kex
*kex_algs
[] = {
194 #ifdef DO_DIFFIE_HELLMAN_GEX
195 &ssh_diffiehellman_gex
,
197 &ssh_diffiehellman
};
199 extern const struct ssh_signkey ssh_dss
;
200 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_dss
};
202 extern const struct ssh_mac ssh_md5
, ssh_sha1
, ssh_sha1_buggy
;
204 static void nullmac_key(unsigned char *key
) { }
205 static void nullmac_generate(unsigned char *blk
, int len
, unsigned long seq
) { }
206 static int nullmac_verify(unsigned char *blk
, int len
, unsigned long seq
) { return 1; }
207 const static struct ssh_mac ssh_mac_none
= {
208 nullmac_key
, nullmac_key
, nullmac_generate
, nullmac_verify
, "none", 0
210 const static struct ssh_mac
*macs
[] = {
211 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
};
212 const static struct ssh_mac
*buggymacs
[] = {
213 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
};
215 static void ssh_comp_none_init(void) { }
216 static int ssh_comp_none_block(unsigned char *block
, int len
,
217 unsigned char **outblock
, int *outlen
) {
220 const static struct ssh_compress ssh_comp_none
= {
222 ssh_comp_none_init
, ssh_comp_none_block
,
223 ssh_comp_none_init
, ssh_comp_none_block
225 extern const struct ssh_compress ssh_zlib
;
226 const static struct ssh_compress
*compressions
[] = {
227 &ssh_zlib
, &ssh_comp_none
};
229 enum { /* channel types */
236 * 2-3-4 tree storing channels.
239 unsigned remoteid
, localid
;
242 struct ssh2_data_channel
{
243 unsigned char *outbuffer
;
244 unsigned outbuflen
, outbufsize
;
245 unsigned remwindow
, remmaxpkt
;
248 struct ssh_agent_channel
{
249 unsigned char *message
;
250 unsigned char msglen
[4];
251 int lensofar
, totallen
;
253 struct ssh_x11_channel
{
268 static SHA_State exhash
, exhashbase
;
270 static Socket s
= NULL
;
272 static unsigned char session_key
[32];
273 static int ssh1_compressing
;
274 static int ssh_agentfwd_enabled
;
275 static int ssh_X11_fwd_enabled
;
276 static const struct ssh_cipher
*cipher
= NULL
;
277 static const struct ssh2_cipher
*cscipher
= NULL
;
278 static const struct ssh2_cipher
*sccipher
= NULL
;
279 static const struct ssh_mac
*csmac
= NULL
;
280 static const struct ssh_mac
*scmac
= NULL
;
281 static const struct ssh_compress
*cscomp
= NULL
;
282 static const struct ssh_compress
*sccomp
= NULL
;
283 static const struct ssh_kex
*kex
= NULL
;
284 static const struct ssh_signkey
*hostkey
= NULL
;
285 int (*ssh_get_password
)(const char *prompt
, char *str
, int maxlen
) = NULL
;
287 static char *savedhost
;
288 static int savedport
;
289 static int ssh_send_ok
;
290 static int ssh_echoing
, ssh_editing
;
292 static tree234
*ssh_channels
; /* indexed by local id */
293 static struct ssh_channel
*mainchan
; /* primary session channel */
297 SSH_STATE_BEFORE_SIZE
,
301 } ssh_state
= SSH_STATE_PREPACKET
;
303 static int size_needed
= FALSE
, eof_needed
= FALSE
;
305 static struct Packet pktin
= { 0, 0, NULL
, NULL
, 0 };
306 static struct Packet pktout
= { 0, 0, NULL
, NULL
, 0 };
307 static unsigned char *deferred_send_data
= NULL
;
308 static int deferred_len
= 0, deferred_size
= 0;
310 static int ssh_version
;
311 static void (*ssh_protocol
)(unsigned char *in
, int inlen
, int ispkt
);
312 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
);
313 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
);
314 static void ssh_size(void);
315 static void ssh_special (Telnet_Special
);
316 static void ssh2_try_send(struct ssh_channel
*c
);
317 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
319 static int (*s_rdpkt
)(unsigned char **data
, int *datalen
);
321 static struct rdpkt1_state_tag
{
322 long len
, pad
, biglen
, to_read
;
323 unsigned long realcrc
, gotcrc
;
329 static struct rdpkt2_state_tag
{
330 long len
, pad
, payload
, packetlen
, maclen
;
333 unsigned long incoming_sequence
;
336 static int ssh_channelcmp(void *av
, void *bv
) {
337 struct ssh_channel
*a
= (struct ssh_channel
*)av
;
338 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
339 if (a
->localid
< b
->localid
) return -1;
340 if (a
->localid
> b
->localid
) return +1;
343 static int ssh_channelfind(void *av
, void *bv
) {
344 unsigned *a
= (unsigned *)av
;
345 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
346 if (*a
< b
->localid
) return -1;
347 if (*a
> b
->localid
) return +1;
351 static void c_write (char *buf
, int len
) {
352 if ((flags
& FLAG_STDERR
)) {
354 for (i
= 0; i
< len
; i
++)
356 fputc(buf
[i
], stderr
);
359 from_backend(1, buf
, len
);
363 * Collect incoming data in the incoming packet buffer.
364 * Decipher and verify the packet when it is completely read.
365 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
366 * Update the *data and *datalen variables.
367 * Return the additional nr of bytes needed, or 0 when
368 * a complete packet is available.
370 static int ssh1_rdpkt(unsigned char **data
, int *datalen
)
372 struct rdpkt1_state_tag
*st
= &rdpkt1_state
;
381 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
382 while ((*datalen
) == 0)
384 st
->len
= (st
->len
<< 8) + **data
;
385 (*data
)++, (*datalen
)--;
389 if (st
->len
== 0x52656d6f) { /* "Remo"te server has closed ... */
390 st
->len
= 0x300; /* big enough to carry to end */
394 st
->pad
= 8 - (st
->len
% 8);
395 st
->biglen
= st
->len
+ st
->pad
;
396 pktin
.length
= st
->len
- 5;
398 if (pktin
.maxlen
< st
->biglen
) {
399 pktin
.maxlen
= st
->biglen
;
400 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->biglen
+APIEXTRA
) :
401 srealloc(pktin
.data
, st
->biglen
+APIEXTRA
));
403 fatalbox("Out of memory");
406 st
->to_read
= st
->biglen
;
408 while (st
->to_read
> 0) {
409 st
->chunk
= st
->to_read
;
410 while ((*datalen
) == 0)
411 crReturn(st
->to_read
);
412 if (st
->chunk
> (*datalen
))
413 st
->chunk
= (*datalen
);
414 memcpy(st
->p
, *data
, st
->chunk
);
416 *datalen
-= st
->chunk
;
418 st
->to_read
-= st
->chunk
;
422 cipher
->decrypt(pktin
.data
, st
->biglen
);
424 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
425 for (st
->i
= 0; st
->i
< st
->biglen
; st
->i
++)
426 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
430 st
->realcrc
= crc32(pktin
.data
, st
->biglen
-4);
431 st
->gotcrc
= GET_32BIT(pktin
.data
+st
->biglen
-4);
432 if (st
->gotcrc
!= st
->realcrc
) {
433 bombout(("Incorrect CRC received on packet"));
437 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
439 if (ssh1_compressing
) {
440 unsigned char *decompblk
;
444 debug(("Packet payload pre-decompression:\n"));
445 for (i
= -1; i
< pktin
.length
; i
++)
446 debug((" %02x", (unsigned char)pktin
.body
[i
]));
449 zlib_decompress_block(pktin
.body
-1, pktin
.length
+1,
450 &decompblk
, &decomplen
);
452 if (pktin
.maxlen
< st
->pad
+ decomplen
) {
453 pktin
.maxlen
= st
->pad
+ decomplen
;
454 pktin
.data
= srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
);
455 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
457 fatalbox("Out of memory");
460 memcpy(pktin
.body
-1, decompblk
, decomplen
);
462 pktin
.length
= decomplen
-1;
464 debug(("Packet payload post-decompression:\n"));
465 for (i
= -1; i
< pktin
.length
; i
++)
466 debug((" %02x", (unsigned char)pktin
.body
[i
]));
471 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
472 pktin
.type
== SSH1_SMSG_STDERR_DATA
||
473 pktin
.type
== SSH1_MSG_DEBUG
||
474 pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
475 pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
476 long strlen
= GET_32BIT(pktin
.body
);
477 if (strlen
+ 4 != pktin
.length
) {
478 bombout(("Received data packet with bogus string length"));
483 pktin
.type
= pktin
.body
[-1];
485 if (pktin
.type
== SSH1_MSG_DEBUG
) {
486 /* log debug message */
488 int strlen
= GET_32BIT(pktin
.body
);
489 strcpy(buf
, "Remote: ");
490 if (strlen
> 70) strlen
= 70;
491 memcpy(buf
+8, pktin
.body
+4, strlen
);
492 buf
[8+strlen
] = '\0';
495 } else if (pktin
.type
== SSH1_MSG_IGNORE
) {
503 static int ssh2_rdpkt(unsigned char **data
, int *datalen
)
505 struct rdpkt2_state_tag
*st
= &rdpkt2_state
;
513 st
->cipherblk
= sccipher
->blksize
;
516 if (st
->cipherblk
< 8)
519 if (pktin
.maxlen
< st
->cipherblk
) {
520 pktin
.maxlen
= st
->cipherblk
;
521 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->cipherblk
+APIEXTRA
) :
522 srealloc(pktin
.data
, st
->cipherblk
+APIEXTRA
));
524 fatalbox("Out of memory");
528 * Acquire and decrypt the first block of the packet. This will
529 * contain the length and padding details.
531 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
532 while ((*datalen
) == 0)
533 crReturn(st
->cipherblk
-st
->i
);
534 pktin
.data
[st
->i
] = *(*data
)++;
538 if (!memcmp(pktin
.data
, "Remo", 4)) {/* "Remo"te server has closed ... */
543 sccipher
->decrypt(pktin
.data
, st
->cipherblk
);
546 * Now get the length and padding figures.
548 st
->len
= GET_32BIT(pktin
.data
);
549 st
->pad
= pktin
.data
[4];
552 * This enables us to deduce the payload length.
554 st
->payload
= st
->len
- st
->pad
- 1;
556 pktin
.length
= st
->payload
+ 5;
559 * So now we can work out the total packet length.
561 st
->packetlen
= st
->len
+ 4;
562 st
->maclen
= scmac ? scmac
->len
: 0;
565 * Adjust memory allocation if packet is too big.
567 if (pktin
.maxlen
< st
->packetlen
+st
->maclen
) {
568 pktin
.maxlen
= st
->packetlen
+st
->maclen
;
569 pktin
.data
= (pktin
.data
== NULL ?
smalloc(pktin
.maxlen
+APIEXTRA
) :
570 srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
572 fatalbox("Out of memory");
576 * Read and decrypt the remainder of the packet.
578 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
; st
->i
++) {
579 while ((*datalen
) == 0)
580 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
581 pktin
.data
[st
->i
] = *(*data
)++;
584 /* Decrypt everything _except_ the MAC. */
586 sccipher
->decrypt(pktin
.data
+ st
->cipherblk
,
587 st
->packetlen
- st
->cipherblk
);
590 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
591 for (st
->i
= 0; st
->i
< st
->packetlen
; st
->i
++)
592 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
599 if (scmac
&& !scmac
->verify(pktin
.data
, st
->len
+4, st
->incoming_sequence
)) {
600 bombout(("Incorrect MAC received on packet"));
603 st
->incoming_sequence
++; /* whether or not we MACed */
606 * Decompress packet payload.
609 unsigned char *newpayload
;
611 if (sccomp
&& sccomp
->decompress(pktin
.data
+5, pktin
.length
-5,
612 &newpayload
, &newlen
)) {
613 if (pktin
.maxlen
< newlen
+5) {
614 pktin
.maxlen
= newlen
+5;
615 pktin
.data
= (pktin
.data
== NULL ?
smalloc(pktin
.maxlen
+APIEXTRA
) :
616 srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
618 fatalbox("Out of memory");
620 pktin
.length
= 5 + newlen
;
621 memcpy(pktin
.data
+5, newpayload
, newlen
);
623 debug(("Post-decompression payload:\r\n"));
624 for (st
->i
= 0; st
->i
< newlen
; st
->i
++)
625 debug((" %02x", (unsigned char)pktin
.data
[5+st
->i
]));
634 pktin
.type
= pktin
.data
[5];
636 if (pktin
.type
== SSH2_MSG_IGNORE
|| pktin
.type
== SSH2_MSG_DEBUG
)
637 goto next_packet
; /* FIXME: print DEBUG message */
642 static void ssh1_pktout_size(int len
) {
645 len
+= 5; /* type and CRC */
649 pktout
.length
= len
-5;
650 if (pktout
.maxlen
< biglen
) {
651 pktout
.maxlen
= biglen
;
653 /* Allocate enough buffer space for extra block
654 * for MS CryptEncrypt() */
655 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+12) :
656 srealloc(pktout
.data
, biglen
+12));
658 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+4) :
659 srealloc(pktout
.data
, biglen
+4));
662 fatalbox("Out of memory");
664 pktout
.body
= pktout
.data
+4+pad
+1;
667 static void s_wrpkt_start(int type
, int len
) {
668 ssh1_pktout_size(len
);
672 static void s_wrpkt(void) {
673 int pad
, len
, biglen
, i
;
676 pktout
.body
[-1] = pktout
.type
;
678 if (ssh1_compressing
) {
679 unsigned char *compblk
;
682 debug(("Packet payload pre-compression:\n"));
683 for (i
= -1; i
< pktout
.length
; i
++)
684 debug((" %02x", (unsigned char)pktout
.body
[i
]));
687 zlib_compress_block(pktout
.body
-1, pktout
.length
+1,
689 ssh1_pktout_size(complen
-1);
690 memcpy(pktout
.body
-1, compblk
, complen
);
693 debug(("Packet payload post-compression:\n"));
694 for (i
= -1; i
< pktout
.length
; i
++)
695 debug((" %02x", (unsigned char)pktout
.body
[i
]));
700 len
= pktout
.length
+ 5; /* type and CRC */
704 for (i
=0; i
<pad
; i
++)
705 pktout
.data
[i
+4] = random_byte();
706 crc
= crc32(pktout
.data
+4, biglen
-4);
707 PUT_32BIT(pktout
.data
+biglen
, crc
);
708 PUT_32BIT(pktout
.data
, len
);
711 debug(("Sending packet len=%d\r\n", biglen
+4));
712 for (i
= 0; i
< biglen
+4; i
++)
713 debug((" %02x", (unsigned char)pktout
.data
[i
]));
717 cipher
->encrypt(pktout
.data
+4, biglen
);
719 sk_write(s
, pktout
.data
, biglen
+4);
723 * Construct a packet with the specified contents and
724 * send it to the server.
726 static void send_packet(int pkttype
, ...)
729 unsigned char *p
, *argp
, argchar
;
730 unsigned long argint
;
731 int pktlen
, argtype
, arglen
;
735 va_start(args
, pkttype
);
736 while ((argtype
= va_arg(args
, int)) != PKT_END
) {
739 (void) va_arg(args
, int);
743 (void) va_arg(args
, char);
747 (void) va_arg(args
, unsigned char *);
748 arglen
= va_arg(args
, int);
752 argp
= va_arg(args
, unsigned char *);
753 arglen
= strlen(argp
);
754 pktlen
+= 4 + arglen
;
757 bn
= va_arg(args
, Bignum
);
758 pktlen
+= ssh1_bignum_length(bn
);
766 s_wrpkt_start(pkttype
, pktlen
);
769 va_start(args
, pkttype
);
770 while ((argtype
= va_arg(args
, int)) != PKT_END
) {
773 argint
= va_arg(args
, int);
774 PUT_32BIT(p
, argint
);
778 argchar
= va_arg(args
, unsigned char);
783 argp
= va_arg(args
, unsigned char *);
784 arglen
= va_arg(args
, int);
785 memcpy(p
, argp
, arglen
);
789 argp
= va_arg(args
, unsigned char *);
790 arglen
= strlen(argp
);
791 PUT_32BIT(p
, arglen
);
792 memcpy(p
+ 4, argp
, arglen
);
796 bn
= va_arg(args
, Bignum
);
797 p
+= ssh1_write_bignum(p
, bn
);
806 static int ssh_versioncmp(char *a
, char *b
) {
808 unsigned long av
, bv
;
810 av
= strtoul(a
, &ae
, 10);
811 bv
= strtoul(b
, &be
, 10);
812 if (av
!= bv
) return (av
< bv ?
-1 : +1);
813 if (*ae
== '.') ae
++;
814 if (*be
== '.') be
++;
815 av
= strtoul(ae
, &ae
, 10);
816 bv
= strtoul(be
, &be
, 10);
817 if (av
!= bv
) return (av
< bv ?
-1 : +1);
823 * Utility routines for putting an SSH-protocol `string' and
824 * `uint32' into a SHA state.
827 static void sha_string(SHA_State
*s
, void *str
, int len
) {
828 unsigned char lenblk
[4];
829 PUT_32BIT(lenblk
, len
);
830 SHA_Bytes(s
, lenblk
, 4);
831 SHA_Bytes(s
, str
, len
);
834 static void sha_uint32(SHA_State
*s
, unsigned i
) {
835 unsigned char intblk
[4];
836 PUT_32BIT(intblk
, i
);
837 SHA_Bytes(s
, intblk
, 4);
841 * SSH2 packet construction functions.
843 static void ssh2_pkt_ensure(int length
) {
844 if (pktout
.maxlen
< length
) {
845 pktout
.maxlen
= length
+ 256;
846 pktout
.data
= (pktout
.data
== NULL ?
smalloc(pktout
.maxlen
+APIEXTRA
) :
847 srealloc(pktout
.data
, pktout
.maxlen
+APIEXTRA
));
849 fatalbox("Out of memory");
852 static void ssh2_pkt_adddata(void *data
, int len
) {
853 pktout
.length
+= len
;
854 ssh2_pkt_ensure(pktout
.length
);
855 memcpy(pktout
.data
+pktout
.length
-len
, data
, len
);
857 static void ssh2_pkt_addbyte(unsigned char byte
) {
858 ssh2_pkt_adddata(&byte
, 1);
860 static void ssh2_pkt_init(int pkt_type
) {
862 ssh2_pkt_addbyte((unsigned char)pkt_type
);
864 static void ssh2_pkt_addbool(unsigned char value
) {
865 ssh2_pkt_adddata(&value
, 1);
867 static void ssh2_pkt_adduint32(unsigned long value
) {
870 ssh2_pkt_adddata(x
, 4);
872 static void ssh2_pkt_addstring_start(void) {
873 ssh2_pkt_adduint32(0);
874 pktout
.savedpos
= pktout
.length
;
876 static void ssh2_pkt_addstring_str(char *data
) {
877 ssh2_pkt_adddata(data
, strlen(data
));
878 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
879 pktout
.length
- pktout
.savedpos
);
881 static void ssh2_pkt_addstring_data(char *data
, int len
) {
882 ssh2_pkt_adddata(data
, len
);
883 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
884 pktout
.length
- pktout
.savedpos
);
886 static void ssh2_pkt_addstring(char *data
) {
887 ssh2_pkt_addstring_start();
888 ssh2_pkt_addstring_str(data
);
890 static char *ssh2_mpint_fmt(Bignum b
, int *len
) {
892 int i
, n
= (ssh1_bignum_bitcount(b
)+7)/8;
895 fatalbox("out of memory");
897 for (i
= 1; i
<= n
; i
++)
898 p
[i
] = bignum_byte(b
, n
-i
);
900 while (i
<= n
&& p
[i
] == 0 && (p
[i
+1] & 0x80) == 0)
902 memmove(p
, p
+i
, n
+1-i
);
906 static void ssh2_pkt_addmp(Bignum b
) {
909 p
= ssh2_mpint_fmt(b
, &len
);
910 ssh2_pkt_addstring_start();
911 ssh2_pkt_addstring_data(p
, len
);
916 * Construct an SSH2 final-form packet: compress it, encrypt it,
917 * put the MAC on it. Final packet, ready to be sent, is stored in
918 * pktout.data. Total length is returned.
920 static int ssh2_pkt_construct(void) {
921 int cipherblk
, maclen
, padding
, i
;
922 static unsigned long outgoing_sequence
= 0;
925 * Compress packet payload.
928 debug(("Pre-compression payload:\r\n"));
929 for (i
= 5; i
< pktout
.length
; i
++)
930 debug((" %02x", (unsigned char)pktout
.data
[i
]));
934 unsigned char *newpayload
;
936 if (cscomp
&& cscomp
->compress(pktout
.data
+5, pktout
.length
-5,
937 &newpayload
, &newlen
)) {
939 ssh2_pkt_adddata(newpayload
, newlen
);
945 * Add padding. At least four bytes, and must also bring total
946 * length (minus MAC) up to a multiple of the block size.
948 cipherblk
= cscipher ? cscipher
->blksize
: 8; /* block size */
949 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
951 padding
+= (cipherblk
- (pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
952 maclen
= csmac ? csmac
->len
: 0;
953 ssh2_pkt_ensure(pktout
.length
+ padding
+ maclen
);
954 pktout
.data
[4] = padding
;
955 for (i
= 0; i
< padding
; i
++)
956 pktout
.data
[pktout
.length
+ i
] = random_byte();
957 PUT_32BIT(pktout
.data
, pktout
.length
+ padding
- 4);
959 csmac
->generate(pktout
.data
, pktout
.length
+ padding
,
961 outgoing_sequence
++; /* whether or not we MACed */
964 debug(("Sending packet len=%d\r\n", pktout
.length
+padding
));
965 for (i
= 0; i
< pktout
.length
+padding
; i
++)
966 debug((" %02x", (unsigned char)pktout
.data
[i
]));
971 cscipher
->encrypt(pktout
.data
, pktout
.length
+ padding
);
973 /* Ready-to-send packet starts at pktout.data. We return length. */
974 return pktout
.length
+ padding
+ maclen
;
978 * Construct and send an SSH2 packet immediately.
980 static void ssh2_pkt_send(void) {
981 int len
= ssh2_pkt_construct();
982 sk_write(s
, pktout
.data
, len
);
986 * Construct an SSH2 packet and add it to a deferred data block.
987 * Useful for sending multiple packets in a single sk_write() call,
988 * to prevent a traffic-analysing listener from being able to work
989 * out the length of any particular packet (such as the password
992 * Note that because SSH2 sequence-numbers its packets, this can
993 * NOT be used as an m4-style `defer' allowing packets to be
994 * constructed in one order and sent in another.
996 static void ssh2_pkt_defer(void) {
997 int len
= ssh2_pkt_construct();
998 if (deferred_len
+ len
> deferred_size
) {
999 deferred_size
= deferred_len
+ len
+ 128;
1000 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
1002 memcpy(deferred_send_data
+deferred_len
, pktout
.data
, len
);
1003 deferred_len
+= len
;
1007 * Send the whole deferred data block constructed by
1010 static void ssh2_pkt_defersend(void) {
1011 sk_write(s
, deferred_send_data
, deferred_len
);
1012 deferred_len
= deferred_size
= 0;
1013 sfree(deferred_send_data
);
1014 deferred_send_data
= NULL
;
1018 void bndebug(char *string
, Bignum b
) {
1021 p
= ssh2_mpint_fmt(b
, &len
);
1022 debug(("%s", string
));
1023 for (i
= 0; i
< len
; i
++)
1024 debug((" %02x", p
[i
]));
1030 static void sha_mpint(SHA_State
*s
, Bignum b
) {
1033 p
= ssh2_mpint_fmt(b
, &len
);
1034 sha_string(s
, p
, len
);
1039 * SSH2 packet decode functions.
1041 static unsigned long ssh2_pkt_getuint32(void) {
1042 unsigned long value
;
1043 if (pktin
.length
- pktin
.savedpos
< 4)
1044 return 0; /* arrgh, no way to decline (FIXME?) */
1045 value
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
1046 pktin
.savedpos
+= 4;
1049 static void ssh2_pkt_getstring(char **p
, int *length
) {
1051 if (pktin
.length
- pktin
.savedpos
< 4)
1053 *length
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
1054 pktin
.savedpos
+= 4;
1055 if (pktin
.length
- pktin
.savedpos
< *length
)
1057 *p
= pktin
.data
+pktin
.savedpos
;
1058 pktin
.savedpos
+= *length
;
1060 static Bignum
ssh2_pkt_getmp(void) {
1065 ssh2_pkt_getstring(&p
, &length
);
1069 bombout(("internal error: Can't handle negative mpints"));
1072 b
= bignum_from_bytes(p
, length
);
1076 static int do_ssh_init(unsigned char c
) {
1078 static char version
[10];
1079 static char vstring
[80];
1080 static char vlog
[sizeof(vstring
)+20];
1085 /* Search for the string "SSH-" in the input. */
1088 static const int transS
[] = { 1, 2, 2, 1 };
1089 static const int transH
[] = { 0, 0, 3, 0 };
1090 static const int transminus
[] = { 0, 0, 0, -1 };
1091 if (c
== 'S') i
= transS
[i
];
1092 else if (c
== 'H') i
= transH
[i
];
1093 else if (c
== '-') i
= transminus
[i
];
1097 crReturn(1); /* get another character */
1100 strcpy(vstring
, "SSH-");
1104 crReturn(1); /* get another char */
1105 if (vsp
< vstring
+sizeof(vstring
)-1)
1111 } else if (i
< sizeof(version
)-1)
1118 ssh_agentfwd_enabled
= FALSE
;
1119 rdpkt2_state
.incoming_sequence
= 0;
1122 sprintf(vlog
, "Server version: %s", vstring
);
1123 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1127 * Server version "1.99" means we can choose whether we use v1
1128 * or v2 protocol. Choice is based on cfg.sshprot.
1130 if (ssh_versioncmp(version
, cfg
.sshprot
== 1 ?
"2.0" : "1.99") >= 0) {
1132 * This is a v2 server. Begin v2 protocol.
1134 char *verstring
= "SSH-2.0-PuTTY";
1135 SHA_Init(&exhashbase
);
1137 * Hash our version string and their version string.
1139 sha_string(&exhashbase
, verstring
, strlen(verstring
));
1140 sha_string(&exhashbase
, vstring
, strcspn(vstring
, "\r\n"));
1141 sprintf(vstring
, "%s\n", verstring
);
1142 sprintf(vlog
, "We claim version: %s", verstring
);
1144 logevent("Using SSH protocol version 2");
1145 sk_write(s
, vstring
, strlen(vstring
));
1146 ssh_protocol
= ssh2_protocol
;
1148 s_rdpkt
= ssh2_rdpkt
;
1151 * This is a v1 server. Begin v1 protocol.
1153 sprintf(vstring
, "SSH-%s-PuTTY\n",
1154 (ssh_versioncmp(version
, "1.5") <= 0 ? version
: "1.5"));
1155 sprintf(vlog
, "We claim version: %s", vstring
);
1156 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1158 logevent("Using SSH protocol version 1");
1159 sk_write(s
, vstring
, strlen(vstring
));
1160 ssh_protocol
= ssh1_protocol
;
1162 s_rdpkt
= ssh1_rdpkt
;
1164 ssh_state
= SSH_STATE_BEFORE_SIZE
;
1169 static void ssh_gotdata(unsigned char *data
, int datalen
)
1174 * To begin with, feed the characters one by one to the
1175 * protocol initialisation / selection function do_ssh_init().
1176 * When that returns 0, we're done with the initial greeting
1177 * exchange and can move on to packet discipline.
1182 crReturnV
; /* more data please */
1183 ret
= do_ssh_init(*data
);
1190 * We emerge from that loop when the initial negotiation is
1191 * over and we have selected an s_rdpkt function. Now pass
1192 * everything to s_rdpkt, and then pass the resulting packets
1193 * to the proper protocol handler.
1198 while (datalen
> 0) {
1199 if ( s_rdpkt(&data
, &datalen
) == 0 ) {
1200 ssh_protocol(NULL
, 0, 1);
1201 if (ssh_state
== SSH_STATE_CLOSED
) {
1211 static int ssh_receive(Socket skt
, int urgent
, char *data
, int len
) {
1213 /* A socket error has occurred. */
1214 ssh_state
= SSH_STATE_CLOSED
;
1217 connection_fatal(data
);
1220 /* Connection has closed. */
1221 ssh_state
= SSH_STATE_CLOSED
;
1226 ssh_gotdata (data
, len
);
1227 if (ssh_state
== SSH_STATE_CLOSED
) {
1238 * Connect to specified host and port.
1239 * Returns an error message, or NULL on success.
1240 * Also places the canonical host name into `realhost'.
1242 static char *connect_to_host(char *host
, int port
, char **realhost
)
1251 savedhost
= smalloc(1+strlen(host
));
1253 fatalbox("Out of memory");
1254 strcpy(savedhost
, host
);
1257 port
= 22; /* default ssh port */
1270 addr
= sk_namelookup(host
, realhost
);
1271 if ( (err
= sk_addr_error(addr
)) )
1281 s
= sk_new(addr
, port
, 0, 1, ssh_receive
);
1282 if ( (err
= sk_socket_error(s
)) )
1286 sk_write(s
, "connect ", 8);
1287 sk_write(s
, FWhost
, strlen(FWhost
));
1290 sprintf(buf
, " %d\n", FWport
);
1291 sk_write(s
, buf
, strlen(buf
));
1299 * Handle the key exchange and user authentication phases.
1301 static int do_ssh1_login(unsigned char *in
, int inlen
, int ispkt
)
1304 unsigned char *rsabuf
, *keystr1
, *keystr2
;
1305 unsigned char cookie
[8];
1306 struct RSAKey servkey
, hostkey
;
1307 struct MD5Context md5c
;
1308 static unsigned long supported_ciphers_mask
, supported_auths_mask
;
1309 static int tried_publickey
;
1310 static unsigned char session_id
[16];
1312 static char username
[100];
1316 if (!ispkt
) crWaitUntil(ispkt
);
1318 if (pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
1319 bombout(("Public key packet not received"));
1323 logevent("Received public keys");
1325 memcpy(cookie
, pktin
.body
, 8);
1327 i
= makekey(pktin
.body
+8, &servkey
, &keystr1
, 0);
1328 j
= makekey(pktin
.body
+8+i
, &hostkey
, &keystr2
, 0);
1331 * Log the host key fingerprint.
1335 logevent("Host key fingerprint is:");
1336 strcpy(logmsg
, " ");
1337 hostkey
.comment
= NULL
;
1338 rsa_fingerprint(logmsg
+strlen(logmsg
), sizeof(logmsg
)-strlen(logmsg
),
1343 supported_ciphers_mask
= GET_32BIT(pktin
.body
+12+i
+j
);
1344 supported_auths_mask
= GET_32BIT(pktin
.body
+16+i
+j
);
1347 MD5Update(&md5c
, keystr2
, hostkey
.bytes
);
1348 MD5Update(&md5c
, keystr1
, servkey
.bytes
);
1349 MD5Update(&md5c
, pktin
.body
, 8);
1350 MD5Final(session_id
, &md5c
);
1352 for (i
=0; i
<32; i
++)
1353 session_key
[i
] = random_byte();
1355 len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
1357 rsabuf
= smalloc(len
);
1359 fatalbox("Out of memory");
1362 * Verify the host key.
1366 * First format the key into a string.
1368 int len
= rsastr_len(&hostkey
);
1369 char fingerprint
[100];
1370 char *keystr
= smalloc(len
);
1372 fatalbox("Out of memory");
1373 rsastr_fmt(keystr
, &hostkey
);
1374 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
1375 verify_ssh_host_key(savedhost
, savedport
, "rsa", keystr
, fingerprint
);
1379 for (i
=0; i
<32; i
++) {
1380 rsabuf
[i
] = session_key
[i
];
1382 rsabuf
[i
] ^= session_id
[i
];
1385 if (hostkey
.bytes
> servkey
.bytes
) {
1386 rsaencrypt(rsabuf
, 32, &servkey
);
1387 rsaencrypt(rsabuf
, servkey
.bytes
, &hostkey
);
1389 rsaencrypt(rsabuf
, 32, &hostkey
);
1390 rsaencrypt(rsabuf
, hostkey
.bytes
, &servkey
);
1393 logevent("Encrypted session key");
1395 switch (cfg
.cipher
) {
1396 case CIPHER_BLOWFISH
: cipher_type
= SSH_CIPHER_BLOWFISH
; break;
1397 case CIPHER_DES
: cipher_type
= SSH_CIPHER_DES
; break;
1398 case CIPHER_3DES
: cipher_type
= SSH_CIPHER_3DES
; break;
1400 c_write("AES not supported in SSH1, falling back to 3DES\r\n", 49);
1401 cipher_type
= SSH_CIPHER_3DES
;
1404 if ((supported_ciphers_mask
& (1 << cipher_type
)) == 0) {
1405 c_write("Selected cipher not supported, falling back to 3DES\r\n", 53);
1406 cipher_type
= SSH_CIPHER_3DES
;
1408 switch (cipher_type
) {
1409 case SSH_CIPHER_3DES
: logevent("Using 3DES encryption"); break;
1410 case SSH_CIPHER_DES
: logevent("Using single-DES encryption"); break;
1411 case SSH_CIPHER_BLOWFISH
: logevent("Using Blowfish encryption"); break;
1414 send_packet(SSH1_CMSG_SESSION_KEY
,
1415 PKT_CHAR
, cipher_type
,
1416 PKT_DATA
, cookie
, 8,
1417 PKT_CHAR
, (len
*8) >> 8, PKT_CHAR
, (len
*8) & 0xFF,
1418 PKT_DATA
, rsabuf
, len
,
1422 logevent("Trying to enable encryption...");
1426 cipher
= cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
1427 cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
1429 cipher
->sesskey(session_key
);
1433 if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1434 bombout(("Encryption not successfully enabled"));
1438 logevent("Successfully started encryption");
1444 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
1445 c_write("login as: ", 10);
1448 crWaitUntil(!ispkt
);
1449 while (inlen
--) switch (c
= *in
++) {
1456 c_write("\b \b", 3);
1462 c_write("\b \b", 3);
1471 if (((c
>= ' ' && c
<= '~') ||
1472 ((unsigned char)c
>= 160)) && pos
< 40) {
1473 username
[pos
++] = c
;
1480 username
[strcspn(username
, "\n\r")] = '\0';
1482 strncpy(username
, cfg
.username
, 99);
1483 username
[99] = '\0';
1486 send_packet(SSH1_CMSG_USER
, PKT_STR
, username
, PKT_END
);
1488 char userlog
[22+sizeof(username
)];
1489 sprintf(userlog
, "Sent username \"%s\"", username
);
1491 if (flags
& FLAG_INTERACTIVE
&&
1492 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
1493 strcat(userlog
, "\r\n");
1494 c_write(userlog
, strlen(userlog
));
1501 tried_publickey
= 0;
1503 while (pktin
.type
== SSH1_SMSG_FAILURE
) {
1504 static char password
[100];
1505 static char prompt
[200];
1508 static int pwpkt_type
;
1510 * Show password prompt, having first obtained it via a TIS
1511 * or CryptoCard exchange if we're doing TIS or CryptoCard
1514 pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
1515 if (agent_exists()) {
1517 * Attempt RSA authentication using Pageant.
1519 static unsigned char request
[5], *response
, *p
;
1520 static int responselen
;
1521 static int i
, nkeys
;
1522 static int authed
= FALSE
;
1525 logevent("Pageant is running. Requesting keys.");
1527 /* Request the keys held by the agent. */
1528 PUT_32BIT(request
, 1);
1529 request
[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES
;
1530 agent_query(request
, 5, &r
, &responselen
);
1531 response
= (unsigned char *)r
;
1534 nkeys
= GET_32BIT(p
); p
+= 4;
1535 { char buf
[64]; sprintf(buf
, "Pageant has %d keys", nkeys
);
1537 for (i
= 0; i
< nkeys
; i
++) {
1538 static struct RSAKey key
;
1539 static Bignum challenge
;
1540 static char *commentp
;
1541 static int commentlen
;
1543 { char buf
[64]; sprintf(buf
, "Trying Pageant key #%d", i
);
1546 p
+= ssh1_read_bignum(p
, &key
.exponent
);
1547 p
+= ssh1_read_bignum(p
, &key
.modulus
);
1548 commentlen
= GET_32BIT(p
); p
+= 4;
1549 commentp
= p
; p
+= commentlen
;
1550 send_packet(SSH1_CMSG_AUTH_RSA
,
1551 PKT_BIGNUM
, key
.modulus
, PKT_END
);
1553 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1554 logevent("Key refused");
1557 logevent("Received RSA challenge");
1558 ssh1_read_bignum(pktin
.body
, &challenge
);
1560 char *agentreq
, *q
, *ret
;
1562 len
= 1 + 4; /* message type, bit count */
1563 len
+= ssh1_bignum_length(key
.exponent
);
1564 len
+= ssh1_bignum_length(key
.modulus
);
1565 len
+= ssh1_bignum_length(challenge
);
1566 len
+= 16; /* session id */
1567 len
+= 4; /* response format */
1568 agentreq
= smalloc(4 + len
);
1569 PUT_32BIT(agentreq
, len
);
1571 *q
++ = SSH_AGENTC_RSA_CHALLENGE
;
1572 PUT_32BIT(q
, ssh1_bignum_bitcount(key
.modulus
));
1574 q
+= ssh1_write_bignum(q
, key
.exponent
);
1575 q
+= ssh1_write_bignum(q
, key
.modulus
);
1576 q
+= ssh1_write_bignum(q
, challenge
);
1577 memcpy(q
, session_id
, 16); q
+= 16;
1578 PUT_32BIT(q
, 1); /* response format */
1579 agent_query(agentreq
, len
+4, &ret
, &retlen
);
1582 if (ret
[4] == SSH_AGENT_RSA_RESPONSE
) {
1583 logevent("Sending Pageant's response");
1584 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1585 PKT_DATA
, ret
+5, 16, PKT_END
);
1588 if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
1589 logevent("Pageant's response accepted");
1590 if (flags
& FLAG_VERBOSE
) {
1591 c_write("Authenticated using RSA key \"",
1593 c_write(commentp
, commentlen
);
1594 c_write("\" from agent\r\n", 14);
1598 logevent("Pageant's response not accepted");
1600 logevent("Pageant failed to answer challenge");
1604 logevent("No reply received from Pageant");
1607 freebn(key
.exponent
);
1608 freebn(key
.modulus
);
1617 if (*cfg
.keyfile
&& !tried_publickey
)
1618 pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
1620 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1622 (supported_auths_mask
& (1<<SSH1_AUTH_TIS
))) {
1623 pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
1624 logevent("Requested TIS authentication");
1625 send_packet(SSH1_CMSG_AUTH_TIS
, PKT_END
);
1627 if (pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
1628 logevent("TIS authentication declined");
1629 if (flags
& FLAG_INTERACTIVE
)
1630 c_write("TIS authentication refused.\r\n", 29);
1632 int challengelen
= ((pktin
.body
[0] << 24) |
1633 (pktin
.body
[1] << 16) |
1634 (pktin
.body
[2] << 8) |
1636 logevent("Received TIS challenge");
1637 if (challengelen
> sizeof(prompt
)-1)
1638 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1639 memcpy(prompt
, pktin
.body
+4, challengelen
);
1640 prompt
[challengelen
] = '\0';
1643 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1645 (supported_auths_mask
& (1<<SSH1_AUTH_CCARD
))) {
1646 pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
1647 logevent("Requested CryptoCard authentication");
1648 send_packet(SSH1_CMSG_AUTH_CCARD
, PKT_END
);
1650 if (pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
1651 logevent("CryptoCard authentication declined");
1652 c_write("CryptoCard authentication refused.\r\n", 29);
1654 int challengelen
= ((pktin
.body
[0] << 24) |
1655 (pktin
.body
[1] << 16) |
1656 (pktin
.body
[2] << 8) |
1658 logevent("Received CryptoCard challenge");
1659 if (challengelen
> sizeof(prompt
)-1)
1660 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1661 memcpy(prompt
, pktin
.body
+4, challengelen
);
1662 strncpy(prompt
+ challengelen
, "\r\nResponse : ",
1663 sizeof(prompt
)-challengelen
);
1664 prompt
[sizeof(prompt
)-1] = '\0';
1667 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
1668 sprintf(prompt
, "%.90s@%.90s's password: ",
1669 username
, savedhost
);
1671 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1672 char *comment
= NULL
;
1673 if (flags
& FLAG_VERBOSE
)
1674 c_write("Trying public key authentication.\r\n", 35);
1675 if (!rsakey_encrypted(cfg
.keyfile
, &comment
)) {
1676 if (flags
& FLAG_VERBOSE
)
1677 c_write("No passphrase required.\r\n", 25);
1680 sprintf(prompt
, "Passphrase for key \"%.100s\": ", comment
);
1684 if (ssh_get_password
) {
1685 if (!ssh_get_password(prompt
, password
, sizeof(password
))) {
1687 * get_password failed to get a password (for
1688 * example because one was supplied on the command
1689 * line which has already failed to work).
1692 logevent("No more passwords to try");
1693 ssh_state
= SSH_STATE_CLOSED
;
1697 c_write(prompt
, strlen(prompt
));
1701 crWaitUntil(!ispkt
);
1702 while (inlen
--) switch (c
= *in
++) {
1719 if (((c
>= ' ' && c
<= '~') ||
1720 ((unsigned char)c
>= 160)) && pos
< sizeof(password
))
1721 password
[pos
++] = c
;
1729 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1731 * Try public key authentication with the specified
1734 static struct RSAKey pubkey
;
1735 static Bignum challenge
, response
;
1737 static unsigned char buffer
[32];
1739 tried_publickey
= 1;
1740 i
= loadrsakey(cfg
.keyfile
, &pubkey
, NULL
, password
);
1742 c_write("Couldn't load public key from ", 30);
1743 c_write(cfg
.keyfile
, strlen(cfg
.keyfile
));
1744 c_write(".\r\n", 3);
1745 continue; /* go and try password */
1748 c_write("Wrong passphrase.\r\n", 19);
1749 tried_publickey
= 0;
1750 continue; /* try again */
1754 * Send a public key attempt.
1756 send_packet(SSH1_CMSG_AUTH_RSA
,
1757 PKT_BIGNUM
, pubkey
.modulus
, PKT_END
);
1760 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1761 c_write("Server refused our public key.\r\n", 32);
1762 continue; /* go and try password */
1764 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1765 bombout(("Bizarre response to offer of public key"));
1768 ssh1_read_bignum(pktin
.body
, &challenge
);
1769 response
= rsadecrypt(challenge
, &pubkey
);
1770 freebn(pubkey
.private_exponent
); /* burn the evidence */
1772 for (i
= 0; i
< 32; i
++) {
1773 buffer
[i
] = bignum_byte(response
, 31-i
);
1777 MD5Update(&md5c
, buffer
, 32);
1778 MD5Update(&md5c
, session_id
, 16);
1779 MD5Final(buffer
, &md5c
);
1781 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1782 PKT_DATA
, buffer
, 16, PKT_END
);
1785 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1786 if (flags
& FLAG_VERBOSE
)
1787 c_write("Failed to authenticate with our public key.\r\n",
1789 continue; /* go and try password */
1790 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1791 bombout(("Bizarre response to RSA authentication response"));
1795 break; /* we're through! */
1797 send_packet(pwpkt_type
, PKT_STR
, password
, PKT_END
);
1799 logevent("Sent password");
1800 memset(password
, 0, strlen(password
));
1802 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1803 if (flags
& FLAG_VERBOSE
)
1804 c_write("Access denied\r\n", 15);
1805 logevent("Authentication refused");
1806 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
1807 logevent("Received disconnect request");
1808 ssh_state
= SSH_STATE_CLOSED
;
1810 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1811 bombout(("Strange packet received, type %d", pktin
.type
));
1816 logevent("Authentication successful");
1821 void sshfwd_close(struct ssh_channel
*c
) {
1823 if (ssh_version
== 1) {
1824 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
, PKT_END
);
1826 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
1827 ssh2_pkt_adduint32(c
->remoteid
);
1831 if (c
->type
== CHAN_X11
) {
1833 logevent("X11 connection terminated");
1838 void sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
) {
1839 if (ssh_version
== 1) {
1840 send_packet(SSH1_MSG_CHANNEL_DATA
,
1841 PKT_INT
, c
->remoteid
,
1846 ssh2_add_channel_data(c
, buf
, len
);
1851 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
) {
1856 while (!do_ssh1_login(in
, inlen
, ispkt
)) {
1859 if (ssh_state
== SSH_STATE_CLOSED
)
1862 if (cfg
.agentfwd
&& agent_exists()) {
1863 logevent("Requesting agent forwarding");
1864 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
1865 do { crReturnV
; } while (!ispkt
);
1866 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1867 bombout(("Protocol confusion"));
1869 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1870 logevent("Agent forwarding refused");
1872 logevent("Agent forwarding enabled");
1873 ssh_agentfwd_enabled
= TRUE
;
1877 if (cfg
.x11_forward
) {
1878 char proto
[20], data
[64];
1879 logevent("Requesting X11 forwarding");
1880 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
1881 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
1882 PKT_STR
, proto
, PKT_STR
, data
,
1885 do { crReturnV
; } while (!ispkt
);
1886 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1887 bombout(("Protocol confusion"));
1889 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1890 logevent("X11 forwarding refused");
1892 logevent("X11 forwarding enabled");
1893 ssh_X11_fwd_enabled
= TRUE
;
1898 send_packet(SSH1_CMSG_REQUEST_PTY
,
1899 PKT_STR
, cfg
.termtype
,
1900 PKT_INT
, rows
, PKT_INT
, cols
,
1901 PKT_INT
, 0, PKT_INT
, 0,
1904 ssh_state
= SSH_STATE_INTERMED
;
1905 do { crReturnV
; } while (!ispkt
);
1906 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1907 bombout(("Protocol confusion"));
1909 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1910 c_write("Server refused to allocate pty\r\n", 32);
1911 ssh_editing
= ssh_echoing
= 1;
1913 logevent("Allocated pty");
1915 ssh_editing
= ssh_echoing
= 1;
1918 if (cfg
.compression
) {
1919 send_packet(SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
1920 do { crReturnV
; } while (!ispkt
);
1921 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1922 bombout(("Protocol confusion"));
1924 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1925 c_write("Server refused to compress\r\n", 32);
1927 logevent("Started compression");
1928 ssh1_compressing
= TRUE
;
1929 zlib_compress_init();
1930 zlib_decompress_init();
1933 if (*cfg
.remote_cmd
)
1934 send_packet(SSH1_CMSG_EXEC_CMD
, PKT_STR
, cfg
.remote_cmd
, PKT_END
);
1936 send_packet(SSH1_CMSG_EXEC_SHELL
, PKT_END
);
1937 logevent("Started session");
1939 ssh_state
= SSH_STATE_SESSION
;
1943 ssh_special(TS_EOF
);
1945 ldisc_send(NULL
, 0); /* cause ldisc to notice changes */
1947 ssh_channels
= newtree234(ssh_channelcmp
);
1951 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
1952 pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
1953 long len
= GET_32BIT(pktin
.body
);
1954 from_backend(pktin
.type
== SSH1_SMSG_STDERR_DATA
,
1956 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
1957 ssh_state
= SSH_STATE_CLOSED
;
1958 logevent("Received disconnect request");
1960 } else if (pktin
.type
== SSH1_SMSG_X11_OPEN
) {
1961 /* Remote side is trying to open a channel to talk to our
1962 * X-Server. Give them back a local channel number. */
1964 struct ssh_channel
*c
, *d
;
1967 logevent("Received X11 connect request");
1968 /* Refuse if X11 forwarding is disabled. */
1969 if (!ssh_X11_fwd_enabled
) {
1970 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
1971 PKT_INT
, GET_32BIT(pktin
.body
),
1973 logevent("Rejected X11 connect request");
1975 c
= smalloc(sizeof(struct ssh_channel
));
1977 if ( x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
1978 logevent("opening X11 forward connection failed");
1980 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
1981 PKT_INT
, GET_32BIT(pktin
.body
),
1984 logevent("opening X11 forward connection succeeded");
1985 for (i
=1, d
= first234(ssh_channels
, &e
); d
; d
= next234(&e
)) {
1987 break; /* found a free number */
1990 c
->remoteid
= GET_32BIT(pktin
.body
);
1993 c
->type
= CHAN_X11
; /* identify channel type */
1994 add234(ssh_channels
, c
);
1995 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
1996 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
1998 logevent("Opened X11 forward channel");
2001 } else if (pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
2002 /* Remote side is trying to open a channel to talk to our
2003 * agent. Give them back a local channel number. */
2005 struct ssh_channel
*c
;
2008 /* Refuse if agent forwarding is disabled. */
2009 if (!ssh_agentfwd_enabled
) {
2010 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
2011 PKT_INT
, GET_32BIT(pktin
.body
),
2015 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
)) {
2017 break; /* found a free number */
2020 c
= smalloc(sizeof(struct ssh_channel
));
2021 c
->remoteid
= GET_32BIT(pktin
.body
);
2024 c
->type
= CHAN_AGENT
; /* identify channel type */
2025 c
->u
.a
.lensofar
= 0;
2026 add234(ssh_channels
, c
);
2027 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
2028 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
2031 } else if (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
2032 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
2033 /* Remote side closes a channel. */
2034 unsigned i
= GET_32BIT(pktin
.body
);
2035 struct ssh_channel
*c
;
2036 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2039 closetype
= (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
2040 send_packet(pktin
.type
, PKT_INT
, c
->remoteid
, PKT_END
);
2041 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
2042 logevent("X11 connection closed");
2043 assert(c
->u
.x11
.s
!= NULL
);
2044 x11_close(c
->u
.x11
.s
);
2047 c
->closes
|= closetype
;
2048 if (c
->closes
== 3) {
2049 del234(ssh_channels
, c
);
2053 } else if (pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
2054 /* Data sent down one of our channels. */
2055 int i
= GET_32BIT(pktin
.body
);
2056 int len
= GET_32BIT(pktin
.body
+4);
2057 unsigned char *p
= pktin
.body
+8;
2058 struct ssh_channel
*c
;
2059 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2063 x11_send(c
->u
.x11
.s
, p
, len
);
2066 /* Data for an agent message. Buffer it. */
2068 if (c
->u
.a
.lensofar
< 4) {
2069 int l
= min(4 - c
->u
.a
.lensofar
, len
);
2070 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
, l
);
2071 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
2073 if (c
->u
.a
.lensofar
== 4) {
2074 c
->u
.a
.totallen
= 4 + GET_32BIT(c
->u
.a
.msglen
);
2075 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
2076 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
2078 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
2079 int l
= min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
, len
);
2080 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
, l
);
2081 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
2083 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
2084 void *reply
, *sentreply
;
2086 agent_query(c
->u
.a
.message
, c
->u
.a
.totallen
,
2091 /* Fake SSH_AGENT_FAILURE. */
2092 sentreply
= "\0\0\0\1\5";
2095 send_packet(SSH1_MSG_CHANNEL_DATA
,
2096 PKT_INT
, c
->remoteid
,
2098 PKT_DATA
, sentreply
, replylen
,
2102 sfree(c
->u
.a
.message
);
2103 c
->u
.a
.lensofar
= 0;
2109 } else if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
2110 /* may be from EXEC_SHELL on some servers */
2111 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2112 /* may be from EXEC_SHELL on some servers
2113 * if no pty is available or in other odd cases. Ignore */
2114 } else if (pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
2115 send_packet(SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
2117 bombout(("Strange packet received: type %d", pktin
.type
));
2122 int len
= min(inlen
, 512);
2123 send_packet(SSH1_CMSG_STDIN_DATA
,
2124 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
2135 * Utility routine for decoding comma-separated strings in KEXINIT.
2137 static int in_commasep_string(char *needle
, char *haystack
, int haylen
) {
2138 int needlen
= strlen(needle
);
2141 * Is it at the start of the string?
2143 if (haylen
>= needlen
&& /* haystack is long enough */
2144 !memcmp(needle
, haystack
, needlen
) && /* initial match */
2145 (haylen
== needlen
|| haystack
[needlen
] == ',')
2146 /* either , or EOS follows */
2150 * If not, search for the next comma and resume after that.
2151 * If no comma found, terminate.
2153 while (haylen
> 0 && *haystack
!= ',')
2154 haylen
--, haystack
++;
2157 haylen
--, haystack
++; /* skip over comma itself */
2162 * SSH2 key creation method.
2164 static void ssh2_mkkey(Bignum K
, char *H
, char *sessid
, char chr
, char *keyspace
) {
2166 /* First 20 bytes. */
2169 SHA_Bytes(&s
, H
, 20);
2170 SHA_Bytes(&s
, &chr
, 1);
2171 SHA_Bytes(&s
, sessid
, 20);
2172 SHA_Final(&s
, keyspace
);
2173 /* Next 20 bytes. */
2176 SHA_Bytes(&s
, H
, 20);
2177 SHA_Bytes(&s
, keyspace
, 20);
2178 SHA_Final(&s
, keyspace
+20);
2182 * Handle the SSH2 transport layer.
2184 static int do_ssh2_transport(unsigned char *in
, int inlen
, int ispkt
)
2186 static int i
, j
, len
, nbits
;
2188 static Bignum p
, g
, e
, f
, K
;
2189 static int kex_init_value
, kex_reply_value
;
2190 static const struct ssh_mac
**maclist
;
2192 static const struct ssh2_cipher
*cscipher_tobe
= NULL
;
2193 static const struct ssh2_cipher
*sccipher_tobe
= NULL
;
2194 static const struct ssh_mac
*csmac_tobe
= NULL
;
2195 static const struct ssh_mac
*scmac_tobe
= NULL
;
2196 static const struct ssh_compress
*cscomp_tobe
= NULL
;
2197 static const struct ssh_compress
*sccomp_tobe
= NULL
;
2198 static char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
2199 static int hostkeylen
, siglen
;
2200 static void *hkey
; /* actual host key */
2201 static unsigned char exchange_hash
[20];
2202 static unsigned char first_exchange_hash
[20];
2203 static unsigned char keyspace
[40];
2204 static const struct ssh2_ciphers
*preferred_cipher
;
2205 static const struct ssh_compress
*preferred_comp
;
2206 static int first_kex
;
2213 * Set up the preferred cipher and compression.
2215 if (cfg
.cipher
== CIPHER_BLOWFISH
) {
2216 preferred_cipher
= &ssh2_blowfish
;
2217 } else if (cfg
.cipher
== CIPHER_DES
) {
2218 logevent("Single DES not supported in SSH2; using 3DES");
2219 preferred_cipher
= &ssh2_3des
;
2220 } else if (cfg
.cipher
== CIPHER_3DES
) {
2221 preferred_cipher
= &ssh2_3des
;
2222 } else if (cfg
.cipher
== CIPHER_AES
) {
2223 preferred_cipher
= &ssh2_aes
;
2225 /* Shouldn't happen, but we do want to initialise to _something_. */
2226 preferred_cipher
= &ssh2_3des
;
2228 if (cfg
.compression
)
2229 preferred_comp
= &ssh_zlib
;
2231 preferred_comp
= &ssh_comp_none
;
2234 * Be prepared to work around the buggy MAC problem.
2237 maclist
= buggymacs
, nmacs
= lenof(buggymacs
);
2239 maclist
= macs
, nmacs
= lenof(macs
);
2243 * Construct and send our key exchange packet.
2245 ssh2_pkt_init(SSH2_MSG_KEXINIT
);
2246 for (i
= 0; i
< 16; i
++)
2247 ssh2_pkt_addbyte((unsigned char)random_byte());
2248 /* List key exchange algorithms. */
2249 ssh2_pkt_addstring_start();
2250 for (i
= 0; i
< lenof(kex_algs
); i
++) {
2251 ssh2_pkt_addstring_str(kex_algs
[i
]->name
);
2252 if (i
< lenof(kex_algs
)-1)
2253 ssh2_pkt_addstring_str(",");
2255 /* List server host key algorithms. */
2256 ssh2_pkt_addstring_start();
2257 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
2258 ssh2_pkt_addstring_str(hostkey_algs
[i
]->name
);
2259 if (i
< lenof(hostkey_algs
)-1)
2260 ssh2_pkt_addstring_str(",");
2262 /* List client->server encryption algorithms. */
2263 ssh2_pkt_addstring_start();
2264 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2265 const struct ssh2_ciphers
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2266 for (j
= 0; j
< c
->nciphers
; j
++) {
2267 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
2268 if (i
< lenof(ciphers
) || j
< c
->nciphers
-1)
2269 ssh2_pkt_addstring_str(",");
2272 /* List server->client encryption algorithms. */
2273 ssh2_pkt_addstring_start();
2274 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2275 const struct ssh2_ciphers
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2276 for (j
= 0; j
< c
->nciphers
; j
++) {
2277 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
2278 if (i
< lenof(ciphers
) || j
< c
->nciphers
-1)
2279 ssh2_pkt_addstring_str(",");
2282 /* List client->server MAC algorithms. */
2283 ssh2_pkt_addstring_start();
2284 for (i
= 0; i
< nmacs
; i
++) {
2285 ssh2_pkt_addstring_str(maclist
[i
]->name
);
2287 ssh2_pkt_addstring_str(",");
2289 /* List server->client MAC algorithms. */
2290 ssh2_pkt_addstring_start();
2291 for (i
= 0; i
< nmacs
; i
++) {
2292 ssh2_pkt_addstring_str(maclist
[i
]->name
);
2294 ssh2_pkt_addstring_str(",");
2296 /* List client->server compression algorithms. */
2297 ssh2_pkt_addstring_start();
2298 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2299 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2300 ssh2_pkt_addstring_str(c
->name
);
2301 if (i
< lenof(compressions
))
2302 ssh2_pkt_addstring_str(",");
2304 /* List server->client compression algorithms. */
2305 ssh2_pkt_addstring_start();
2306 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2307 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2308 ssh2_pkt_addstring_str(c
->name
);
2309 if (i
< lenof(compressions
))
2310 ssh2_pkt_addstring_str(",");
2312 /* List client->server languages. Empty list. */
2313 ssh2_pkt_addstring_start();
2314 /* List server->client languages. Empty list. */
2315 ssh2_pkt_addstring_start();
2316 /* First KEX packet does _not_ follow, because we're not that brave. */
2317 ssh2_pkt_addbool(FALSE
);
2319 ssh2_pkt_adduint32(0);
2321 exhash
= exhashbase
;
2322 sha_string(&exhash
, pktout
.data
+5, pktout
.length
-5);
2326 if (!ispkt
) crWaitUntil(ispkt
);
2327 sha_string(&exhash
, pktin
.data
+5, pktin
.length
-5);
2330 * Now examine the other side's KEXINIT to see what we're up
2333 if (pktin
.type
!= SSH2_MSG_KEXINIT
) {
2334 bombout(("expected key exchange packet from server"));
2337 kex
= NULL
; hostkey
= NULL
; cscipher_tobe
= NULL
; sccipher_tobe
= NULL
;
2338 csmac_tobe
= NULL
; scmac_tobe
= NULL
; cscomp_tobe
= NULL
; sccomp_tobe
= NULL
;
2339 pktin
.savedpos
+= 16; /* skip garbage cookie */
2340 ssh2_pkt_getstring(&str
, &len
); /* key exchange algorithms */
2341 for (i
= 0; i
< lenof(kex_algs
); i
++) {
2342 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
2347 ssh2_pkt_getstring(&str
, &len
); /* host key algorithms */
2348 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
2349 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
2350 hostkey
= hostkey_algs
[i
];
2354 ssh2_pkt_getstring(&str
, &len
); /* client->server cipher */
2355 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2356 const struct ssh2_ciphers
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2357 for (j
= 0; j
< c
->nciphers
; j
++) {
2358 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
2359 cscipher_tobe
= c
->list
[j
];
2366 ssh2_pkt_getstring(&str
, &len
); /* server->client cipher */
2367 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2368 const struct ssh2_ciphers
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2369 for (j
= 0; j
< c
->nciphers
; j
++) {
2370 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
2371 sccipher_tobe
= c
->list
[j
];
2378 ssh2_pkt_getstring(&str
, &len
); /* client->server mac */
2379 for (i
= 0; i
< nmacs
; i
++) {
2380 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2381 csmac_tobe
= maclist
[i
];
2385 ssh2_pkt_getstring(&str
, &len
); /* server->client mac */
2386 for (i
= 0; i
< nmacs
; i
++) {
2387 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2388 scmac_tobe
= maclist
[i
];
2392 ssh2_pkt_getstring(&str
, &len
); /* client->server compression */
2393 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2394 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2395 if (in_commasep_string(c
->name
, str
, len
)) {
2400 ssh2_pkt_getstring(&str
, &len
); /* server->client compression */
2401 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2402 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2403 if (in_commasep_string(c
->name
, str
, len
)) {
2410 * If we're doing Diffie-Hellman group exchange, start by
2411 * requesting a group.
2413 if (kex
== &ssh_diffiehellman_gex
) {
2416 logevent("Doing Diffie-Hellman group exchange");
2418 * Work out number of bits. We start with the maximum key
2419 * length of either cipher...
2421 csbits
= cscipher_tobe
->keylen
;
2422 scbits
= sccipher_tobe
->keylen
;
2423 nbits
= (csbits
> scbits ? csbits
: scbits
);
2424 /* The keys only have 160-bit entropy, since they're based on
2425 * a SHA-1 hash. So cap the key size at 160 bits. */
2426 if (nbits
> 160) nbits
= 160;
2428 * ... and then work out how big a DH group we will need to
2429 * allow that much data.
2431 nbits
= 512 << ((nbits
-1) / 64);
2432 ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
2433 ssh2_pkt_adduint32(nbits
);
2437 if (pktin
.type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
2438 bombout(("expected key exchange group packet from server"));
2441 p
= ssh2_pkt_getmp();
2442 g
= ssh2_pkt_getmp();
2443 dh_setup_group(p
, g
);
2444 kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
2445 kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
2448 kex_init_value
= SSH2_MSG_KEXDH_INIT
;
2449 kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
2452 logevent("Doing Diffie-Hellman key exchange");
2454 * Now generate and send e for Diffie-Hellman.
2457 ssh2_pkt_init(kex_init_value
);
2462 if (pktin
.type
!= kex_reply_value
) {
2463 bombout(("expected key exchange reply packet from server"));
2466 ssh2_pkt_getstring(&hostkeydata
, &hostkeylen
);
2467 f
= ssh2_pkt_getmp();
2468 ssh2_pkt_getstring(&sigdata
, &siglen
);
2472 sha_string(&exhash
, hostkeydata
, hostkeylen
);
2473 if (kex
== &ssh_diffiehellman_gex
) {
2474 sha_uint32(&exhash
, nbits
);
2475 sha_mpint(&exhash
, p
);
2476 sha_mpint(&exhash
, g
);
2478 sha_mpint(&exhash
, e
);
2479 sha_mpint(&exhash
, f
);
2480 sha_mpint(&exhash
, K
);
2481 SHA_Final(&exhash
, exchange_hash
);
2486 debug(("Exchange hash is:\r\n"));
2487 for (i
= 0; i
< 20; i
++)
2488 debug((" %02x", exchange_hash
[i
]));
2492 hkey
= hostkey
->newkey(hostkeydata
, hostkeylen
);
2493 if (!hostkey
->verifysig(hkey
, sigdata
, siglen
, exchange_hash
, 20)) {
2494 bombout(("Server failed host key check"));
2499 * Expect SSH2_MSG_NEWKEYS from server.
2502 if (pktin
.type
!= SSH2_MSG_NEWKEYS
) {
2503 bombout(("expected new-keys packet from server"));
2508 * Authenticate remote host: verify host key. (We've already
2509 * checked the signature of the exchange hash.)
2511 keystr
= hostkey
->fmtkey(hkey
);
2512 fingerprint
= hostkey
->fingerprint(hkey
);
2513 verify_ssh_host_key(savedhost
, savedport
, hostkey
->keytype
,
2514 keystr
, fingerprint
);
2515 if (first_kex
) { /* don't bother logging this in rekeys */
2516 logevent("Host key fingerprint is:");
2517 logevent(fingerprint
);
2521 hostkey
->freekey(hkey
);
2524 * Send SSH2_MSG_NEWKEYS.
2526 ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
2530 * Create and initialise session keys.
2532 cscipher
= cscipher_tobe
;
2533 sccipher
= sccipher_tobe
;
2536 cscomp
= cscomp_tobe
;
2537 sccomp
= sccomp_tobe
;
2538 cscomp
->compress_init();
2539 sccomp
->decompress_init();
2541 * Set IVs after keys. Here we use the exchange hash from the
2542 * _first_ key exchange.
2545 memcpy(first_exchange_hash
, exchange_hash
, sizeof(exchange_hash
));
2546 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'C', keyspace
);
2547 cscipher
->setcskey(keyspace
);
2548 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'D', keyspace
);
2549 sccipher
->setsckey(keyspace
);
2550 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'A', keyspace
);
2551 cscipher
->setcsiv(keyspace
);
2552 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'B', keyspace
);
2553 sccipher
->setsciv(keyspace
);
2554 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'E', keyspace
);
2555 csmac
->setcskey(keyspace
);
2556 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'F', keyspace
);
2557 scmac
->setsckey(keyspace
);
2560 * If this is the first key exchange phase, we must pass the
2561 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
2562 * wants to see it but because it will need time to initialise
2563 * itself before it sees an actual packet. In subsequent key
2564 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
2565 * it would only confuse the layer above.
2573 * Now we're encrypting. Begin returning 1 to the protocol main
2574 * function so that other things can run on top of the
2575 * transport. If we ever see a KEXINIT, we must go back to the
2578 while (!(ispkt
&& pktin
.type
== SSH2_MSG_KEXINIT
)) {
2581 logevent("Server initiated key re-exchange");
2582 goto begin_key_exchange
;
2588 * Add data to an SSH2 channel output buffer.
2590 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
) {
2591 if (c
->v2
.outbufsize
<
2592 c
->v2
.outbuflen
+ len
) {
2594 c
->v2
.outbuflen
+ len
+ 1024;
2595 c
->v2
.outbuffer
= srealloc(c
->v2
.outbuffer
,
2598 memcpy(c
->v2
.outbuffer
+ c
->v2
.outbuflen
,
2600 c
->v2
.outbuflen
+= len
;
2604 * Attempt to send data on an SSH2 channel.
2606 static void ssh2_try_send(struct ssh_channel
*c
) {
2607 while (c
->v2
.remwindow
> 0 &&
2608 c
->v2
.outbuflen
> 0) {
2609 unsigned len
= c
->v2
.remwindow
;
2610 if (len
> c
->v2
.outbuflen
)
2611 len
= c
->v2
.outbuflen
;
2612 if (len
> c
->v2
.remmaxpkt
)
2613 len
= c
->v2
.remmaxpkt
;
2614 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
2615 ssh2_pkt_adduint32(c
->remoteid
);
2616 ssh2_pkt_addstring_start();
2617 ssh2_pkt_addstring_data(c
->v2
.outbuffer
, len
);
2619 c
->v2
.outbuflen
-= len
;
2620 memmove(c
->v2
.outbuffer
, c
->v2
.outbuffer
+len
,
2622 c
->v2
.remwindow
-= len
;
2627 * Handle the SSH2 userauth and connection layers.
2629 static void do_ssh2_authconn(unsigned char *in
, int inlen
, int ispkt
)
2631 static unsigned long remote_winsize
;
2632 static unsigned long remote_maxpkt
;
2637 * Request userauth protocol, and await a response to it.
2639 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
2640 ssh2_pkt_addstring("ssh-userauth");
2642 crWaitUntilV(ispkt
);
2643 if (pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
2644 bombout(("Server refused user authentication protocol"));
2649 * FIXME: currently we support only password authentication.
2650 * (This places us technically in violation of the SSH2 spec.
2651 * We must fix this.)
2655 * Get a username and a password.
2657 static char username
[100];
2658 static char password
[100];
2662 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
2663 c_write("login as: ", 10);
2666 crWaitUntilV(!ispkt
);
2667 while (inlen
--) switch (c
= *in
++) {
2674 c_write("\b \b", 3);
2680 c_write("\b \b", 3);
2689 if (((c
>= ' ' && c
<= '~') ||
2690 ((unsigned char)c
>= 160)) && pos
< 40) {
2691 username
[pos
++] = c
;
2698 username
[strcspn(username
, "\n\r")] = '\0';
2701 strncpy(username
, cfg
.username
, 99);
2702 username
[99] = '\0';
2703 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
2704 sprintf(stuff
, "Using username \"%s\".\r\n", username
);
2705 c_write(stuff
, strlen(stuff
));
2709 if (ssh_get_password
) {
2711 sprintf(prompt
, "%.90s@%.90s's password: ", username
, savedhost
);
2712 if (!ssh_get_password(prompt
, password
, sizeof(password
))) {
2714 * get_password failed to get a password (for
2715 * example because one was supplied on the command
2716 * line which has already failed to work).
2719 logevent("No more passwords to try");
2720 ssh_state
= SSH_STATE_CLOSED
;
2724 c_write("password: ", 10);
2729 crWaitUntilV(!ispkt
);
2730 while (inlen
--) switch (c
= *in
++) {
2747 if (((c
>= ' ' && c
<= '~') ||
2748 ((unsigned char)c
>= 160)) && pos
< 40)
2749 password
[pos
++] = c
;
2757 * We send the password packet lumped tightly together with
2758 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
2759 * string long enough to make the total length of the two
2760 * packets constant. This should ensure that a passive
2761 * listener doing traffic analyis can't work out the length
2764 * For this to work, we need an assumption about the
2765 * maximum length of the password packet. I think 256 is
2766 * pretty conservative. Anyone using a password longer than
2767 * that probably doesn't have much to worry about from
2768 * people who find out how long their password is!
2770 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
2771 ssh2_pkt_addstring(username
);
2772 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2773 ssh2_pkt_addstring("password");
2774 ssh2_pkt_addbool(FALSE
);
2775 ssh2_pkt_addstring(password
);
2778 * We'll include a string that's an exact multiple of the
2779 * cipher block size. If the cipher is NULL for some
2780 * reason, we don't do this trick at all because we gain
2785 ssh2_pkt_init(SSH2_MSG_IGNORE
);
2786 ssh2_pkt_addstring_start();
2787 for (i
= deferred_len
; i
<= 256; i
+= cscipher
->blksize
) {
2788 for (j
= 0; j
< cscipher
->blksize
; j
++) {
2789 char c
= (char)random_byte();
2790 ssh2_pkt_addstring_data(&c
, 1);
2795 ssh2_pkt_defersend();
2797 crWaitUntilV(ispkt
);
2798 if (pktin
.type
!= SSH2_MSG_USERAUTH_SUCCESS
) {
2799 c_write("Access denied\r\n", 15);
2800 logevent("Authentication refused");
2806 * Now we're authenticated for the connection protocol. The
2807 * connection protocol will automatically have started at this
2808 * point; there's no need to send SERVICE_REQUEST.
2812 * So now create a channel with a session in it.
2814 mainchan
= smalloc(sizeof(struct ssh_channel
));
2815 mainchan
->localid
= 100; /* as good as any */
2816 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
2817 ssh2_pkt_addstring("session");
2818 ssh2_pkt_adduint32(mainchan
->localid
);
2819 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
2820 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
2822 crWaitUntilV(ispkt
);
2823 if (pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
2824 bombout(("Server refused to open a session"));
2826 /* FIXME: error data comes back in FAILURE packet */
2828 if (ssh2_pkt_getuint32() != mainchan
->localid
) {
2829 bombout(("Server's channel confirmation cited wrong channel"));
2832 mainchan
->remoteid
= ssh2_pkt_getuint32();
2833 mainchan
->type
= CHAN_MAINSESSION
;
2834 mainchan
->closes
= 0;
2835 mainchan
->v2
.remwindow
= ssh2_pkt_getuint32();
2836 mainchan
->v2
.remmaxpkt
= ssh2_pkt_getuint32();
2837 mainchan
->v2
.outbuffer
= NULL
;
2838 mainchan
->v2
.outbuflen
= mainchan
->v2
.outbufsize
= 0;
2839 ssh_channels
= newtree234(ssh_channelcmp
);
2840 add234(ssh_channels
, mainchan
);
2841 logevent("Opened channel for session");
2844 * Potentially enable X11 forwarding.
2846 if (cfg
.x11_forward
) {
2847 char proto
[20], data
[64];
2848 logevent("Requesting X11 forwarding");
2849 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
2850 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2851 ssh2_pkt_adduint32(mainchan
->remoteid
);
2852 ssh2_pkt_addstring("x11-req");
2853 ssh2_pkt_addbool(1); /* want reply */
2854 ssh2_pkt_addbool(0); /* many connections */
2855 ssh2_pkt_addstring(proto
);
2856 ssh2_pkt_addstring(data
);
2857 ssh2_pkt_adduint32(0); /* screen number */
2861 crWaitUntilV(ispkt
);
2862 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2863 unsigned i
= ssh2_pkt_getuint32();
2864 struct ssh_channel
*c
;
2865 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2867 continue; /* nonexistent channel */
2868 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2870 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2872 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2873 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2874 bombout(("Server got confused by X11 forwarding request"));
2877 logevent("X11 forwarding refused");
2879 logevent("X11 forwarding enabled");
2880 ssh_X11_fwd_enabled
= TRUE
;
2885 * Now allocate a pty for the session.
2888 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2889 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
2890 ssh2_pkt_addstring("pty-req");
2891 ssh2_pkt_addbool(1); /* want reply */
2892 ssh2_pkt_addstring(cfg
.termtype
);
2893 ssh2_pkt_adduint32(cols
);
2894 ssh2_pkt_adduint32(rows
);
2895 ssh2_pkt_adduint32(0); /* pixel width */
2896 ssh2_pkt_adduint32(0); /* pixel height */
2897 ssh2_pkt_addstring_start();
2898 ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
2900 ssh_state
= SSH_STATE_INTERMED
;
2903 crWaitUntilV(ispkt
);
2904 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 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2912 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2914 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2915 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2916 bombout(("Server got confused by pty request"));
2919 c_write("Server refused to allocate pty\r\n", 32);
2920 ssh_editing
= ssh_echoing
= 1;
2922 logevent("Allocated pty");
2925 ssh_editing
= ssh_echoing
= 1;
2929 * Start a shell or a remote command.
2931 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2932 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
2933 if (cfg
.ssh_subsys
) {
2934 ssh2_pkt_addstring("subsystem");
2935 ssh2_pkt_addbool(1); /* want reply */
2936 ssh2_pkt_addstring(cfg
.remote_cmd
);
2937 } else if (*cfg
.remote_cmd
) {
2938 ssh2_pkt_addstring("exec");
2939 ssh2_pkt_addbool(1); /* want reply */
2940 ssh2_pkt_addstring(cfg
.remote_cmd
);
2942 ssh2_pkt_addstring("shell");
2943 ssh2_pkt_addbool(1); /* want reply */
2947 crWaitUntilV(ispkt
);
2948 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2949 unsigned i
= ssh2_pkt_getuint32();
2950 struct ssh_channel
*c
;
2951 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2953 continue; /* nonexistent channel */
2954 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2956 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2957 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2958 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2959 bombout(("Server got confused by shell/command request"));
2962 bombout(("Server refused to start a shell/command"));
2965 logevent("Started a shell/command");
2968 ssh_state
= SSH_STATE_SESSION
;
2972 ssh_special(TS_EOF
);
2977 ldisc_send(NULL
, 0); /* cause ldisc to notice changes */
2980 static int try_send
;
2984 if (pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
2985 pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
2988 unsigned i
= ssh2_pkt_getuint32();
2989 struct ssh_channel
*c
;
2990 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2992 continue; /* nonexistent channel */
2993 if (pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
2994 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR
)
2995 continue; /* extended but not stderr */
2996 ssh2_pkt_getstring(&data
, &length
);
2999 case CHAN_MAINSESSION
:
3000 from_backend(pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
,
3004 x11_send(c
->u
.x11
.s
, data
, length
);
3008 * Enlarge the window again at the remote
3009 * side, just in case it ever runs down and
3010 * they fail to send us any more data.
3012 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
3013 ssh2_pkt_adduint32(c
->remoteid
);
3014 ssh2_pkt_adduint32(length
);
3017 } else if (pktin
.type
== SSH2_MSG_DISCONNECT
) {
3018 ssh_state
= SSH_STATE_CLOSED
;
3019 logevent("Received disconnect message");
3021 } else if (pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
3022 continue; /* exit status et al; ignore (FIXME?) */
3023 } else if (pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
3024 unsigned i
= ssh2_pkt_getuint32();
3025 struct ssh_channel
*c
;
3027 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3029 continue; /* nonexistent channel */
3031 if (c
->type
== CHAN_X11
) {
3033 * Remote EOF on an X11 channel means we should
3034 * wrap up and close the channel ourselves.
3036 x11_close(c
->u
.x11
.s
);
3039 } else if (pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
3040 unsigned i
= ssh2_pkt_getuint32();
3041 struct ssh_channel
*c
;
3044 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3046 continue; /* nonexistent channel */
3047 if (c
->closes
== 0) {
3048 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3049 ssh2_pkt_adduint32(c
->remoteid
);
3052 /* Do pre-close processing on the channel. */
3054 case CHAN_MAINSESSION
:
3055 break; /* nothing to see here, move along */
3059 del234(ssh_channels
, c
);
3060 sfree(c
->v2
.outbuffer
);
3064 * See if that was the last channel left open.
3066 c
= first234(ssh_channels
, &e
);
3068 logevent("All channels closed. Disconnecting");
3069 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
3070 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
3071 ssh2_pkt_addstring("All open channels closed");
3072 ssh2_pkt_addstring("en"); /* language tag */
3074 ssh_state
= SSH_STATE_CLOSED
;
3077 continue; /* remote sends close; ignore (FIXME) */
3078 } else if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
3079 unsigned i
= ssh2_pkt_getuint32();
3080 struct ssh_channel
*c
;
3081 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3083 continue; /* nonexistent channel */
3084 mainchan
->v2
.remwindow
+= ssh2_pkt_getuint32();
3086 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
3090 struct ssh_channel
*c
;
3091 ssh2_pkt_getstring(&type
, &typelen
);
3092 c
= smalloc(sizeof(struct ssh_channel
));
3094 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
3095 if (!ssh_X11_fwd_enabled
)
3096 error
= "X11 forwarding is not enabled";
3097 else if ( x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
3098 error
= "Unable to open an X11 connection";
3103 error
= "Unsupported channel type requested";
3106 c
->remoteid
= ssh2_pkt_getuint32();
3108 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
3109 ssh2_pkt_adduint32(c
->remoteid
);
3110 ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED
);
3111 ssh2_pkt_addstring(error
);
3112 ssh2_pkt_addstring("en"); /* language tag */
3116 struct ssh_channel
*d
;
3120 for (i
=1, d
= first234(ssh_channels
, &e
); d
;
3123 break; /* found a free number */
3128 c
->v2
.remwindow
= ssh2_pkt_getuint32();
3129 c
->v2
.remmaxpkt
= ssh2_pkt_getuint32();
3130 c
->v2
.outbuffer
= NULL
;
3131 c
->v2
.outbuflen
= c
->v2
.outbufsize
= 0;
3132 add234(ssh_channels
, c
);
3133 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
3134 ssh2_pkt_adduint32(c
->remoteid
);
3135 ssh2_pkt_adduint32(c
->localid
);
3136 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
3137 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
3141 bombout(("Strange packet received: type %d", pktin
.type
));
3146 * We have spare data. Add it to the channel buffer.
3148 ssh2_add_channel_data(mainchan
, in
, inlen
);
3153 struct ssh_channel
*c
;
3155 * Try to send data on all channels if we can.
3157 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
))
3166 * Handle the top-level SSH2 protocol.
3168 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
)
3170 if (do_ssh2_transport(in
, inlen
, ispkt
) == 0)
3172 do_ssh2_authconn(in
, inlen
, ispkt
);
3176 * Called to set up the connection.
3178 * Returns an error message, or NULL on success.
3180 static char *ssh_init (char *host
, int port
, char **realhost
) {
3184 if(crypto_startup() == 0)
3185 return "Microsoft high encryption pack not installed!";
3192 p
= connect_to_host(host
, port
, realhost
);
3200 * Called to send data down the Telnet connection.
3202 static void ssh_send (char *buf
, int len
) {
3203 if (s
== NULL
|| ssh_protocol
== NULL
)
3206 ssh_protocol(buf
, len
, 0);
3210 * Called to set the size of the window from SSH's POV.
3212 static void ssh_size(void) {
3213 switch (ssh_state
) {
3214 case SSH_STATE_BEFORE_SIZE
:
3215 case SSH_STATE_PREPACKET
:
3216 case SSH_STATE_CLOSED
:
3217 break; /* do nothing */
3218 case SSH_STATE_INTERMED
:
3219 size_needed
= TRUE
; /* buffer for later */
3221 case SSH_STATE_SESSION
:
3223 if (ssh_version
== 1) {
3224 send_packet(SSH1_CMSG_WINDOW_SIZE
,
3225 PKT_INT
, rows
, PKT_INT
, cols
,
3226 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
3228 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
3229 ssh2_pkt_adduint32(mainchan
->remoteid
);
3230 ssh2_pkt_addstring("window-change");
3231 ssh2_pkt_addbool(0);
3232 ssh2_pkt_adduint32(cols
);
3233 ssh2_pkt_adduint32(rows
);
3234 ssh2_pkt_adduint32(0);
3235 ssh2_pkt_adduint32(0);
3244 * Send Telnet special codes. TS_EOF is useful for `plink', so you
3245 * can send an EOF and collect resulting output (e.g. `plink
3248 static void ssh_special (Telnet_Special code
) {
3249 if (code
== TS_EOF
) {
3250 if (ssh_state
!= SSH_STATE_SESSION
) {
3252 * Buffer the EOF in case we are pre-SESSION, so we can
3253 * send it as soon as we reach SESSION.
3259 if (ssh_version
== 1) {
3260 send_packet(SSH1_CMSG_EOF
, PKT_END
);
3262 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
3263 ssh2_pkt_adduint32(mainchan
->remoteid
);
3266 logevent("Sent EOF message");
3267 } else if (code
== TS_PING
) {
3268 if (ssh_state
== SSH_STATE_CLOSED
|| ssh_state
== SSH_STATE_PREPACKET
)
3270 if (ssh_version
== 1) {
3271 send_packet(SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
3273 ssh2_pkt_init(SSH2_MSG_IGNORE
);
3274 ssh2_pkt_addstring_start();
3282 static Socket
ssh_socket(void) { return s
; }
3284 static int ssh_sendok(void) { return ssh_send_ok
; }
3286 static int ssh_ldisc(int option
) {
3287 if (option
== LD_ECHO
) return ssh_echoing
;
3288 if (option
== LD_EDIT
) return ssh_editing
;
3292 Backend ssh_backend
= {