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Enable PuTTY command line to deal with "user@host" format
[u/mdw/putty] / ssh.c
CommitLineData
374330e2 1#include <stdio.h>
2#include <stdlib.h>
fb09bf1c 3#include <stdarg.h>
4#include <assert.h>
4d331a77 5#ifndef AUTO_WINSOCK
6#ifdef WINSOCK_TWO
7#include <winsock2.h>
8#else
374330e2 9#include <winsock.h>
4d331a77 10#endif
11#endif
374330e2 12
13#include "putty.h"
dacbd0e8 14#include "tree234.h"
fb09bf1c 15#include "ssh.h"
16#include "scp.h"
374330e2 17
18#ifndef FALSE
19#define FALSE 0
20#endif
21#ifndef TRUE
22#define TRUE 1
23#endif
24
fb09bf1c 25#define logevent(s) { logevent(s); \
67779be7 26 if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \
fb09bf1c 27 fprintf(stderr, "%s\n", s); }
28
8d5de777 29#define bombout(msg) ( ssh_state == SSH_STATE_CLOSED, closesocket(s), \
30 s = INVALID_SOCKET, connection_fatal msg )
31
d211621f 32#define SSH1_MSG_DISCONNECT 1 /* 0x1 */
33#define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
34#define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
35#define SSH1_CMSG_USER 4 /* 0x4 */
36#define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
37#define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
38#define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
39#define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
40#define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
41#define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
42#define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
43#define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
44#define SSH1_SMSG_SUCCESS 14 /* 0xe */
45#define SSH1_SMSG_FAILURE 15 /* 0xf */
46#define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
47#define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
48#define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
49#define SSH1_CMSG_EOF 19 /* 0x13 */
50#define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
51#define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
52#define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
53#define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
54#define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
55#define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
56#define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
57#define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
58#define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
59#define SSH1_MSG_IGNORE 32 /* 0x20 */
60#define SSH1_MSG_DEBUG 36 /* 0x24 */
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 */
67
68#define SSH1_AUTH_TIS 5 /* 0x5 */
69#define SSH1_AUTH_CCARD 16 /* 0x10 */
70
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 */
79
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 */
110
111#define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
112#define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
113#define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
114#define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
115
116#define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
fb09bf1c 117
118#define GET_32BIT(cp) \
119 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
120 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
121 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
122 ((unsigned long)(unsigned char)(cp)[3]))
123
124#define PUT_32BIT(cp, value) { \
125 (cp)[0] = (unsigned char)((value) >> 24); \
126 (cp)[1] = (unsigned char)((value) >> 16); \
127 (cp)[2] = (unsigned char)((value) >> 8); \
128 (cp)[3] = (unsigned char)(value); }
129
7cca0d81 130enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM };
972a41c8 131
374330e2 132/* Coroutine mechanics for the sillier bits of the code */
133#define crBegin1 static int crLine = 0;
134#define crBegin2 switch(crLine) { case 0:;
135#define crBegin crBegin1; crBegin2;
136#define crFinish(z) } crLine = 0; return (z)
137#define crFinishV } crLine = 0; return
138#define crReturn(z) \
139 do {\
140 crLine=__LINE__; return (z); case __LINE__:;\
141 } while (0)
142#define crReturnV \
143 do {\
144 crLine=__LINE__; return; case __LINE__:;\
145 } while (0)
146#define crStop(z) do{ crLine = 0; return (z); }while(0)
147#define crStopV do{ crLine = 0; return; }while(0)
fb09bf1c 148#define crWaitUntil(c) do { crReturn(0); } while (!(c))
7cca0d81 149#define crWaitUntilV(c) do { crReturnV; } while (!(c))
374330e2 150
e5574168 151extern struct ssh_cipher ssh_3des;
033b4cef 152extern struct ssh_cipher ssh_3des_ssh2;
e5574168 153extern struct ssh_cipher ssh_des;
5e8358ad 154extern struct ssh_cipher ssh_blowfish_ssh1;
155extern struct ssh_cipher ssh_blowfish_ssh2;
e5574168 156
5e8358ad 157/*
158 * Ciphers for SSH2. We miss out single-DES because it isn't
159 * supported; also 3DES and Blowfish are both done differently from
160 * SSH1. (3DES uses outer chaining; Blowfish has the opposite
161 * endianness and different-sized keys.)
162 *
163 * The first entry in this array is set up to be whatever the user
164 * asks for as a cipher. Thereafter there is a fixed preference
165 * order of fallback ciphers.
166 */
167struct ssh_cipher *ciphers[] = { NULL, &ssh_blowfish_ssh2, &ssh_3des_ssh2 };
e5574168 168
169extern struct ssh_kex ssh_diffiehellman;
170struct ssh_kex *kex_algs[] = { &ssh_diffiehellman };
171
172extern struct ssh_hostkey ssh_dss;
173struct ssh_hostkey *hostkey_algs[] = { &ssh_dss };
174
175extern struct ssh_mac ssh_sha1;
176
dacbd0e8 177static SHA_State exhash;
e5574168 178
d39f364a 179static void nullmac_key(unsigned char *key) { }
e5574168 180static void nullmac_generate(unsigned char *blk, int len, unsigned long seq) { }
181static int nullmac_verify(unsigned char *blk, int len, unsigned long seq) { return 1; }
182struct ssh_mac ssh_mac_none = {
d39f364a 183 nullmac_key, nullmac_key, nullmac_generate, nullmac_verify, "none", 0
e5574168 184};
185struct ssh_mac *macs[] = { &ssh_sha1, &ssh_mac_none };
186
187struct ssh_compress ssh_comp_none = {
188 "none"
189};
190struct ssh_compress *compressions[] = { &ssh_comp_none };
191
374330e2 192static SOCKET s = INVALID_SOCKET;
193
194static unsigned char session_key[32];
195static struct ssh_cipher *cipher = NULL;
e5574168 196static struct ssh_cipher *cscipher = NULL;
197static struct ssh_cipher *sccipher = NULL;
198static struct ssh_mac *csmac = NULL;
199static struct ssh_mac *scmac = NULL;
200static struct ssh_compress *cscomp = NULL;
201static struct ssh_compress *sccomp = NULL;
202static struct ssh_kex *kex = NULL;
203static struct ssh_hostkey *hostkey = NULL;
85ee8208 204int (*ssh_get_password)(const char *prompt, char *str, int maxlen) = NULL;
374330e2 205
206static char *savedhost;
8ccc75b0 207static int ssh_send_ok;
374330e2 208
dacbd0e8 209/*
210 * 2-3-4 tree storing channels.
211 */
212struct ssh_channel {
d211621f 213 unsigned remoteid, localid;
dacbd0e8 214 int type;
215 int closes;
216 union {
217 struct ssh_agent_channel {
218 unsigned char *message;
219 unsigned char msglen[4];
220 int lensofar, totallen;
221 } a;
d211621f 222 struct ssh2_data_channel {
223 unsigned char *outbuffer;
224 unsigned outbuflen, outbufsize;
225 unsigned remwindow, remmaxpkt;
226 } v2;
dacbd0e8 227 } u;
228};
229static tree234 *ssh_channels; /* indexed by local id */
230static int ssh_channelcmp(void *av, void *bv) {
231 struct ssh_channel *a = (struct ssh_channel *)av;
232 struct ssh_channel *b = (struct ssh_channel *)bv;
233 if (a->localid < b->localid) return -1;
234 if (a->localid > b->localid) return +1;
235 return 0;
236}
237static int ssh_channelfind(void *av, void *bv) {
d211621f 238 unsigned *a = (unsigned *)av;
dacbd0e8 239 struct ssh_channel *b = (struct ssh_channel *)bv;
240 if (*a < b->localid) return -1;
241 if (*a > b->localid) return +1;
242 return 0;
243}
244
d211621f 245static struct ssh_channel *mainchan; /* primary session channel */
246
374330e2 247static enum {
248 SSH_STATE_BEFORE_SIZE,
249 SSH_STATE_INTERMED,
21248260 250 SSH_STATE_SESSION,
251 SSH_STATE_CLOSED
374330e2 252} ssh_state = SSH_STATE_BEFORE_SIZE;
253
254static int size_needed = FALSE;
255
256static void s_write (char *buf, int len) {
257 while (len > 0) {
258 int i = send (s, buf, len, 0);
4017be6d 259 noise_ultralight(i);
8d5de777 260 if (i <= 0) {
261 bombout(("Lost connection while sending"));
262 return;
263 }
374330e2 264 if (i > 0)
265 len -= i, buf += i;
266 }
267}
268
269static int s_read (char *buf, int len) {
270 int ret = 0;
271 while (len > 0) {
272 int i = recv (s, buf, len, 0);
4017be6d 273 noise_ultralight(i);
374330e2 274 if (i > 0)
275 len -= i, buf += i, ret += i;
276 else
277 return i;
278 }
279 return ret;
280}
281
282static void c_write (char *buf, int len) {
67779be7 283 if ((flags & FLAG_STDERR)) {
4017be6d 284 int i;
285 for (i = 0; i < len; i++)
286 if (buf[i] != '\r')
287 fputc(buf[i], stderr);
fb09bf1c 288 return;
289 }
c9def1b8 290 while (len--)
291 c_write1(*buf++);
374330e2 292}
293
294struct Packet {
295 long length;
296 int type;
374330e2 297 unsigned char *data;
298 unsigned char *body;
e5574168 299 long savedpos;
374330e2 300 long maxlen;
301};
302
fb09bf1c 303static struct Packet pktin = { 0, 0, NULL, NULL, 0 };
304static struct Packet pktout = { 0, 0, NULL, NULL, 0 };
374330e2 305
6abbf9e3 306static int ssh_version;
e5574168 307static void (*ssh_protocol)(unsigned char *in, int inlen, int ispkt);
308static void ssh1_protocol(unsigned char *in, int inlen, int ispkt);
309static void ssh2_protocol(unsigned char *in, int inlen, int ispkt);
374330e2 310static void ssh_size(void);
311
e5574168 312static int (*s_rdpkt)(unsigned char **data, int *datalen);
fb09bf1c 313
314/*
315 * Collect incoming data in the incoming packet buffer.
e5574168 316 * Decipher and verify the packet when it is completely read.
317 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
fb09bf1c 318 * Update the *data and *datalen variables.
319 * Return the additional nr of bytes needed, or 0 when
320 * a complete packet is available.
321 */
e5574168 322static int ssh1_rdpkt(unsigned char **data, int *datalen)
fb09bf1c 323{
324 static long len, pad, biglen, to_read;
572f871e 325 static unsigned long realcrc, gotcrc;
fb09bf1c 326 static unsigned char *p;
327 static int i;
374330e2 328
329 crBegin;
374330e2 330
fb09bf1c 331next_packet:
37508af4 332
fb09bf1c 333 pktin.type = 0;
334 pktin.length = 0;
374330e2 335
fb09bf1c 336 for (i = len = 0; i < 4; i++) {
337 while ((*datalen) == 0)
338 crReturn(4-i);
339 len = (len << 8) + **data;
340 (*data)++, (*datalen)--;
341 }
374330e2 342
fb09bf1c 343#ifdef FWHACK
344 if (len == 0x52656d6f) { /* "Remo"te server has closed ... */
345 len = 0x300; /* big enough to carry to end */
346 }
347#endif
374330e2 348
fb09bf1c 349 pad = 8 - (len % 8);
350 biglen = len + pad;
351 pktin.length = len - 5;
352
353 if (pktin.maxlen < biglen) {
354 pktin.maxlen = biglen;
e5574168 355 pktin.data = (pktin.data == NULL ? malloc(biglen+APIEXTRA) :
356 realloc(pktin.data, biglen+APIEXTRA));
fb09bf1c 357 if (!pktin.data)
358 fatalbox("Out of memory");
359 }
374330e2 360
fb09bf1c 361 to_read = biglen;
362 p = pktin.data;
363 while (to_read > 0) {
364 static int chunk;
365 chunk = to_read;
366 while ((*datalen) == 0)
367 crReturn(to_read);
368 if (chunk > (*datalen))
369 chunk = (*datalen);
370 memcpy(p, *data, chunk);
371 *data += chunk;
372 *datalen -= chunk;
373 p += chunk;
374 to_read -= chunk;
375 }
374330e2 376
fb09bf1c 377 if (cipher)
378 cipher->decrypt(pktin.data, biglen);
374330e2 379
fb09bf1c 380 pktin.type = pktin.data[pad];
381 pktin.body = pktin.data + pad + 1;
374330e2 382
fb09bf1c 383 realcrc = crc32(pktin.data, biglen-4);
384 gotcrc = GET_32BIT(pktin.data+biglen-4);
385 if (gotcrc != realcrc) {
8d5de777 386 bombout(("Incorrect CRC received on packet"));
387 crReturn(0);
fb09bf1c 388 }
572f871e 389
e5574168 390 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
391 pktin.type == SSH1_SMSG_STDERR_DATA ||
392 pktin.type == SSH1_MSG_DEBUG ||
18515c51 393 pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE ||
394 pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
fb09bf1c 395 long strlen = GET_32BIT(pktin.body);
8d5de777 396 if (strlen + 4 != pktin.length) {
397 bombout(("Received data packet with bogus string length"));
398 crReturn(0);
399 }
fb09bf1c 400 }
401
e5574168 402 if (pktin.type == SSH1_MSG_DEBUG) {
fb09bf1c 403 /* log debug message */
404 char buf[80];
405 int strlen = GET_32BIT(pktin.body);
406 strcpy(buf, "Remote: ");
407 if (strlen > 70) strlen = 70;
408 memcpy(buf+8, pktin.body+4, strlen);
409 buf[8+strlen] = '\0';
410 logevent(buf);
411 goto next_packet;
e5574168 412 } else if (pktin.type == SSH1_MSG_IGNORE) {
fb09bf1c 413 /* do nothing */
414 goto next_packet;
415 }
416
417 crFinish(0);
418}
419
e5574168 420static int ssh2_rdpkt(unsigned char **data, int *datalen)
421{
422 static long len, pad, payload, packetlen, maclen;
423 static int i;
424 static int cipherblk;
425 static unsigned long incoming_sequence = 0;
426
427 crBegin;
428
429next_packet:
430
431 pktin.type = 0;
432 pktin.length = 0;
433
434 if (cipher)
435 cipherblk = cipher->blksize;
436 else
437 cipherblk = 8;
438 if (cipherblk < 8)
439 cipherblk = 8;
440
441 if (pktin.maxlen < cipherblk) {
442 pktin.maxlen = cipherblk;
443 pktin.data = (pktin.data == NULL ? malloc(cipherblk+APIEXTRA) :
444 realloc(pktin.data, cipherblk+APIEXTRA));
445 if (!pktin.data)
446 fatalbox("Out of memory");
447 }
448
449 /*
450 * Acquire and decrypt the first block of the packet. This will
451 * contain the length and padding details.
452 */
453 for (i = len = 0; i < cipherblk; i++) {
454 while ((*datalen) == 0)
455 crReturn(cipherblk-i);
456 pktin.data[i] = *(*data)++;
457 (*datalen)--;
458 }
459#ifdef FWHACK
460 if (!memcmp(pktin.data, "Remo", 4)) {/* "Remo"te server has closed ... */
461 /* FIXME */
462 }
463#endif
464 if (sccipher)
465 sccipher->decrypt(pktin.data, cipherblk);
466
467 /*
468 * Now get the length and padding figures.
469 */
470 len = GET_32BIT(pktin.data);
471 pad = pktin.data[4];
472
473 /*
474 * This enables us to deduce the payload length.
475 */
476 payload = len - pad - 1;
477
478 pktin.length = payload + 5;
479
480 /*
481 * So now we can work out the total packet length.
482 */
483 packetlen = len + 4;
484 maclen = scmac ? scmac->len : 0;
485
486 /*
487 * Adjust memory allocation if packet is too big.
488 */
59dcd2a8 489 if (pktin.maxlen < packetlen+maclen) {
490 pktin.maxlen = packetlen+maclen;
491 pktin.data = (pktin.data == NULL ? malloc(pktin.maxlen+APIEXTRA) :
492 realloc(pktin.data, pktin.maxlen+APIEXTRA));
e5574168 493 if (!pktin.data)
494 fatalbox("Out of memory");
495 }
496
497 /*
498 * Read and decrypt the remainder of the packet.
499 */
500 for (i = cipherblk; i < packetlen + maclen; i++) {
501 while ((*datalen) == 0)
502 crReturn(packetlen + maclen - i);
503 pktin.data[i] = *(*data)++;
504 (*datalen)--;
505 }
506 /* Decrypt everything _except_ the MAC. */
507 if (sccipher)
508 sccipher->decrypt(pktin.data + cipherblk, packetlen - cipherblk);
509
7cca0d81 510#if 0
d39f364a 511 debug(("Got packet len=%d pad=%d\r\n", len, pad));
512 for (i = 0; i < packetlen; i++)
513 debug((" %02x", (unsigned char)pktin.data[i]));
514 debug(("\r\n"));
7cca0d81 515#endif
d39f364a 516
e5574168 517 /*
518 * Check the MAC.
519 */
8d5de777 520 if (scmac && !scmac->verify(pktin.data, len+4, incoming_sequence)) {
521 bombout(("Incorrect MAC received on packet"));
522 crReturn(0);
523 }
033b4cef 524 incoming_sequence++; /* whether or not we MACed */
e5574168 525
526 pktin.savedpos = 6;
527 pktin.type = pktin.data[5];
e5574168 528
7cca0d81 529 if (pktin.type == SSH2_MSG_IGNORE || pktin.type == SSH2_MSG_DEBUG)
530 goto next_packet; /* FIXME: print DEBUG message */
e5574168 531
532 crFinish(0);
533}
534
fb09bf1c 535static void ssh_gotdata(unsigned char *data, int datalen)
536{
537 while (datalen > 0) {
85ee8208 538 if ( s_rdpkt(&data, &datalen) == 0 ) {
374330e2 539 ssh_protocol(NULL, 0, 1);
85ee8208 540 if (ssh_state == SSH_STATE_CLOSED) {
541 return;
542 }
543 }
374330e2 544 }
374330e2 545}
546
fb09bf1c 547
374330e2 548static void s_wrpkt_start(int type, int len) {
549 int pad, biglen;
550
551 len += 5; /* type and CRC */
552 pad = 8 - (len%8);
553 biglen = len + pad;
554
555 pktout.length = len-5;
556 if (pktout.maxlen < biglen) {
557 pktout.maxlen = biglen;
8f203108 558#ifdef MSCRYPTOAPI
fb09bf1c 559 /* Allocate enough buffer space for extra block
8f203108 560 * for MS CryptEncrypt() */
fb09bf1c 561 pktout.data = (pktout.data == NULL ? malloc(biglen+12) :
562 realloc(pktout.data, biglen+12));
8f203108 563#else
c1f5f956 564 pktout.data = (pktout.data == NULL ? malloc(biglen+4) :
565 realloc(pktout.data, biglen+4));
8f203108 566#endif
374330e2 567 if (!pktout.data)
568 fatalbox("Out of memory");
569 }
570
571 pktout.type = type;
572 pktout.body = pktout.data+4+pad+1;
573}
574
575static void s_wrpkt(void) {
576 int pad, len, biglen, i;
577 unsigned long crc;
578
579 len = pktout.length + 5; /* type and CRC */
580 pad = 8 - (len%8);
581 biglen = len + pad;
582
583 pktout.body[-1] = pktout.type;
584 for (i=0; i<pad; i++)
585 pktout.data[i+4] = random_byte();
586 crc = crc32(pktout.data+4, biglen-4);
fb09bf1c 587 PUT_32BIT(pktout.data+biglen, crc);
588 PUT_32BIT(pktout.data, len);
374330e2 589
590 if (cipher)
591 cipher->encrypt(pktout.data+4, biglen);
592
593 s_write(pktout.data, biglen+4);
594}
595
fb09bf1c 596/*
597 * Construct a packet with the specified contents and
598 * send it to the server.
599 */
600static void send_packet(int pkttype, ...)
601{
602 va_list args;
603 unsigned char *p, *argp, argchar;
604 unsigned long argint;
605 int pktlen, argtype, arglen;
7cca0d81 606 Bignum bn;
fb09bf1c 607
608 pktlen = 0;
609 va_start(args, pkttype);
610 while ((argtype = va_arg(args, int)) != PKT_END) {
611 switch (argtype) {
612 case PKT_INT:
613 (void) va_arg(args, int);
614 pktlen += 4;
615 break;
616 case PKT_CHAR:
617 (void) va_arg(args, char);
618 pktlen++;
619 break;
620 case PKT_DATA:
621 (void) va_arg(args, unsigned char *);
622 arglen = va_arg(args, int);
623 pktlen += arglen;
624 break;
625 case PKT_STR:
626 argp = va_arg(args, unsigned char *);
627 arglen = strlen(argp);
628 pktlen += 4 + arglen;
629 break;
7cca0d81 630 case PKT_BIGNUM:
631 bn = va_arg(args, Bignum);
5c58ad2d 632 pktlen += ssh1_bignum_length(bn);
7cca0d81 633 break;
fb09bf1c 634 default:
635 assert(0);
636 }
637 }
638 va_end(args);
639
640 s_wrpkt_start(pkttype, pktlen);
641 p = pktout.body;
642
643 va_start(args, pkttype);
644 while ((argtype = va_arg(args, int)) != PKT_END) {
645 switch (argtype) {
646 case PKT_INT:
647 argint = va_arg(args, int);
648 PUT_32BIT(p, argint);
649 p += 4;
650 break;
651 case PKT_CHAR:
652 argchar = va_arg(args, unsigned char);
653 *p = argchar;
654 p++;
655 break;
656 case PKT_DATA:
657 argp = va_arg(args, unsigned char *);
658 arglen = va_arg(args, int);
659 memcpy(p, argp, arglen);
660 p += arglen;
661 break;
662 case PKT_STR:
663 argp = va_arg(args, unsigned char *);
664 arglen = strlen(argp);
665 PUT_32BIT(p, arglen);
666 memcpy(p + 4, argp, arglen);
667 p += 4 + arglen;
668 break;
7cca0d81 669 case PKT_BIGNUM:
670 bn = va_arg(args, Bignum);
5c58ad2d 671 p += ssh1_write_bignum(p, bn);
7cca0d81 672 break;
fb09bf1c 673 }
674 }
675 va_end(args);
676
677 s_wrpkt();
678}
679
680
681/*
682 * Connect to specified host and port.
683 * Returns an error message, or NULL on success.
684 * Also places the canonical host name into `realhost'.
685 */
686static char *connect_to_host(char *host, int port, char **realhost)
687{
688 SOCKADDR_IN addr;
689 struct hostent *h;
690 unsigned long a;
691#ifdef FWHACK
692 char *FWhost;
693 int FWport;
694#endif
695
696 savedhost = malloc(1+strlen(host));
697 if (!savedhost)
698 fatalbox("Out of memory");
699 strcpy(savedhost, host);
700
701 if (port < 0)
702 port = 22; /* default ssh port */
703
704#ifdef FWHACK
705 FWhost = host;
706 FWport = port;
707 host = FWSTR;
708 port = 23;
709#endif
710
711 /*
712 * Try to find host.
713 */
714 if ( (a = inet_addr(host)) == (unsigned long) INADDR_NONE) {
715 if ( (h = gethostbyname(host)) == NULL)
716 switch (WSAGetLastError()) {
717 case WSAENETDOWN: return "Network is down";
718 case WSAHOST_NOT_FOUND: case WSANO_DATA:
719 return "Host does not exist";
720 case WSATRY_AGAIN: return "Host not found";
721 default: return "gethostbyname: unknown error";
722 }
723 memcpy (&a, h->h_addr, sizeof(a));
724 *realhost = h->h_name;
725 } else
726 *realhost = host;
727#ifdef FWHACK
728 *realhost = FWhost;
729#endif
730 a = ntohl(a);
731
732 /*
733 * Open socket.
734 */
735 s = socket(AF_INET, SOCK_STREAM, 0);
736 if (s == INVALID_SOCKET)
737 switch (WSAGetLastError()) {
738 case WSAENETDOWN: return "Network is down";
739 case WSAEAFNOSUPPORT: return "TCP/IP support not present";
740 default: return "socket(): unknown error";
741 }
742
743 /*
744 * Bind to local address.
745 */
746 addr.sin_family = AF_INET;
747 addr.sin_addr.s_addr = htonl(INADDR_ANY);
748 addr.sin_port = htons(0);
749 if (bind (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
750 switch (WSAGetLastError()) {
751 case WSAENETDOWN: return "Network is down";
752 default: return "bind(): unknown error";
753 }
754
755 /*
756 * Connect to remote address.
757 */
758 addr.sin_addr.s_addr = htonl(a);
759 addr.sin_port = htons((short)port);
760 if (connect (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
761 switch (WSAGetLastError()) {
762 case WSAENETDOWN: return "Network is down";
763 case WSAECONNREFUSED: return "Connection refused";
764 case WSAENETUNREACH: return "Network is unreachable";
765 case WSAEHOSTUNREACH: return "No route to host";
766 default: return "connect(): unknown error";
767 }
768
769#ifdef FWHACK
770 send(s, "connect ", 8, 0);
771 send(s, FWhost, strlen(FWhost), 0);
772 {
773 char buf[20];
774 sprintf(buf, " %d\n", FWport);
775 send (s, buf, strlen(buf), 0);
776 }
777#endif
778
779 return NULL;
780}
781
9697bfd2 782static int ssh_versioncmp(char *a, char *b) {
783 char *ae, *be;
784 unsigned long av, bv;
785
43aa02a7 786 av = strtoul(a, &ae, 10);
787 bv = strtoul(b, &be, 10);
9697bfd2 788 if (av != bv) return (av < bv ? -1 : +1);
789 if (*ae == '.') ae++;
790 if (*be == '.') be++;
43aa02a7 791 av = strtoul(ae, &ae, 10);
792 bv = strtoul(be, &be, 10);
9697bfd2 793 if (av != bv) return (av < bv ? -1 : +1);
794 return 0;
795}
796
e5574168 797
798/*
799 * Utility routine for putting an SSH-protocol `string' into a SHA
800 * state.
801 */
802#include <stdio.h>
803void sha_string(SHA_State *s, void *str, int len) {
804 unsigned char lenblk[4];
e5574168 805 PUT_32BIT(lenblk, len);
e5574168 806 SHA_Bytes(s, lenblk, 4);
e5574168 807 SHA_Bytes(s, str, len);
808}
809
7cca0d81 810/*
811 * SSH2 packet construction functions.
812 */
813void ssh2_pkt_adddata(void *data, int len) {
814 pktout.length += len;
815 if (pktout.maxlen < pktout.length) {
816 pktout.maxlen = pktout.length + 256;
817 pktout.data = (pktout.data == NULL ? malloc(pktout.maxlen+APIEXTRA) :
818 realloc(pktout.data, pktout.maxlen+APIEXTRA));
819 if (!pktout.data)
820 fatalbox("Out of memory");
821 }
822 memcpy(pktout.data+pktout.length-len, data, len);
823}
824void ssh2_pkt_addbyte(unsigned char byte) {
825 ssh2_pkt_adddata(&byte, 1);
826}
827void ssh2_pkt_init(int pkt_type) {
828 pktout.length = 5;
829 ssh2_pkt_addbyte((unsigned char)pkt_type);
830}
831void ssh2_pkt_addbool(unsigned char value) {
832 ssh2_pkt_adddata(&value, 1);
833}
834void ssh2_pkt_adduint32(unsigned long value) {
835 unsigned char x[4];
836 PUT_32BIT(x, value);
837 ssh2_pkt_adddata(x, 4);
838}
839void ssh2_pkt_addstring_start(void) {
840 ssh2_pkt_adduint32(0);
841 pktout.savedpos = pktout.length;
842}
843void ssh2_pkt_addstring_str(char *data) {
844 ssh2_pkt_adddata(data, strlen(data));
845 PUT_32BIT(pktout.data + pktout.savedpos - 4,
846 pktout.length - pktout.savedpos);
847}
848void ssh2_pkt_addstring_data(char *data, int len) {
849 ssh2_pkt_adddata(data, len);
850 PUT_32BIT(pktout.data + pktout.savedpos - 4,
851 pktout.length - pktout.savedpos);
852}
853void ssh2_pkt_addstring(char *data) {
854 ssh2_pkt_addstring_start();
855 ssh2_pkt_addstring_str(data);
856}
857char *ssh2_mpint_fmt(Bignum b, int *len) {
858 unsigned char *p;
859 int i, n = b[0];
860 p = malloc(n * 2 + 1);
861 if (!p)
862 fatalbox("out of memory");
863 p[0] = 0;
864 for (i = 0; i < n; i++) {
865 p[i*2+1] = (b[n-i] >> 8) & 0xFF;
866 p[i*2+2] = (b[n-i] ) & 0xFF;
867 }
868 i = 0;
869 while (p[i] == 0 && (p[i+1] & 0x80) == 0)
870 i++;
871 memmove(p, p+i, n*2+1-i);
872 *len = n*2+1-i;
873 return p;
874}
875void ssh2_pkt_addmp(Bignum b) {
876 unsigned char *p;
877 int len;
878 p = ssh2_mpint_fmt(b, &len);
879 ssh2_pkt_addstring_start();
880 ssh2_pkt_addstring_data(p, len);
881 free(p);
882}
883void ssh2_pkt_send(void) {
884 int cipherblk, maclen, padding, i;
885 static unsigned long outgoing_sequence = 0;
886
887 /*
888 * Add padding. At least four bytes, and must also bring total
889 * length (minus MAC) up to a multiple of the block size.
890 */
891 cipherblk = cipher ? cipher->blksize : 8; /* block size */
892 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
893 padding = 4;
894 padding += (cipherblk - (pktout.length + padding) % cipherblk) % cipherblk;
895 pktout.data[4] = padding;
896 for (i = 0; i < padding; i++)
897 pktout.data[pktout.length + i] = random_byte();
898 PUT_32BIT(pktout.data, pktout.length + padding - 4);
899 if (csmac)
900 csmac->generate(pktout.data, pktout.length + padding,
901 outgoing_sequence);
902 outgoing_sequence++; /* whether or not we MACed */
903
904#if 0
905 debug(("Sending packet len=%d\r\n", pktout.length+padding));
906 for (i = 0; i < pktout.length+padding; i++)
907 debug((" %02x", (unsigned char)pktout.data[i]));
908 debug(("\r\n"));
909#endif
910
911 if (cscipher)
912 cscipher->encrypt(pktout.data, pktout.length + padding);
913 maclen = csmac ? csmac->len : 0;
914
915 s_write(pktout.data, pktout.length + padding + maclen);
916}
917
918#if 0
919void bndebug(char *string, Bignum b) {
920 unsigned char *p;
921 int i, len;
922 p = ssh2_mpint_fmt(b, &len);
923 debug(("%s", string));
924 for (i = 0; i < len; i++)
925 debug((" %02x", p[i]));
926 debug(("\r\n"));
927 free(p);
928}
929#endif
930
931void sha_mpint(SHA_State *s, Bignum b) {
932 unsigned char *p;
933 int len;
934 p = ssh2_mpint_fmt(b, &len);
935 sha_string(s, p, len);
936 free(p);
937}
938
939/*
940 * SSH2 packet decode functions.
941 */
942unsigned long ssh2_pkt_getuint32(void) {
943 unsigned long value;
944 if (pktin.length - pktin.savedpos < 4)
945 return 0; /* arrgh, no way to decline (FIXME?) */
946 value = GET_32BIT(pktin.data+pktin.savedpos);
947 pktin.savedpos += 4;
948 return value;
949}
950void ssh2_pkt_getstring(char **p, int *length) {
951 *p = NULL;
952 if (pktin.length - pktin.savedpos < 4)
953 return;
954 *length = GET_32BIT(pktin.data+pktin.savedpos);
955 pktin.savedpos += 4;
956 if (pktin.length - pktin.savedpos < *length)
957 return;
958 *p = pktin.data+pktin.savedpos;
959 pktin.savedpos += *length;
960}
961Bignum ssh2_pkt_getmp(void) {
962 char *p;
963 int i, j, length;
964 Bignum b;
965
966 ssh2_pkt_getstring(&p, &length);
967 if (!p)
968 return NULL;
8d5de777 969 if (p[0] & 0x80) {
970 bombout(("internal error: Can't handle negative mpints"));
971 return NULL;
972 }
7cca0d81 973 b = newbn((length+1)/2);
974 for (i = 0; i < length; i++) {
975 j = length - 1 - i;
976 if (j & 1)
977 b[j/2+1] |= ((unsigned char)p[i]) << 8;
978 else
979 b[j/2+1] |= ((unsigned char)p[i]);
980 }
981 return b;
982}
983
374330e2 984static int do_ssh_init(void) {
c5e9c988 985 char c, *vsp;
374330e2 986 char version[10];
c5e9c988 987 char vstring[80];
988 char vlog[sizeof(vstring)+20];
374330e2 989 int i;
990
991#ifdef FWHACK
992 i = 0;
993 while (s_read(&c, 1) == 1) {
994 if (c == 'S' && i < 2) i++;
995 else if (c == 'S' && i == 2) i = 2;
996 else if (c == 'H' && i == 2) break;
997 else i = 0;
998 }
999#else
1000 if (s_read(&c,1) != 1 || c != 'S') return 0;
1001 if (s_read(&c,1) != 1 || c != 'S') return 0;
1002 if (s_read(&c,1) != 1 || c != 'H') return 0;
1003#endif
c5e9c988 1004 strcpy(vstring, "SSH-");
1005 vsp = vstring+4;
374330e2 1006 if (s_read(&c,1) != 1 || c != '-') return 0;
1007 i = 0;
1008 while (1) {
1009 if (s_read(&c,1) != 1)
1010 return 0;
c5e9c988 1011 if (vsp < vstring+sizeof(vstring)-1)
1012 *vsp++ = c;
374330e2 1013 if (i >= 0) {
1014 if (c == '-') {
1015 version[i] = '\0';
1016 i = -1;
1017 } else if (i < sizeof(version)-1)
1018 version[i++] = c;
1019 }
1020 else if (c == '\n')
1021 break;
1022 }
1023
c5e9c988 1024 *vsp = 0;
1025 sprintf(vlog, "Server version: %s", vstring);
1026 vlog[strcspn(vlog, "\r\n")] = '\0';
1027 logevent(vlog);
1028
adf799dd 1029 /*
1030 * Server version "1.99" means we can choose whether we use v1
1031 * or v2 protocol. Choice is based on cfg.sshprot.
1032 */
1033 if (ssh_versioncmp(version, cfg.sshprot == 1 ? "2.0" : "1.99") >= 0) {
e5574168 1034 /*
1035 * This is a v2 server. Begin v2 protocol.
1036 */
1037 char *verstring = "SSH-2.0-PuTTY";
1038 SHA_Init(&exhash);
1039 /*
1040 * Hash our version string and their version string.
1041 */
1042 sha_string(&exhash, verstring, strlen(verstring));
1043 sha_string(&exhash, vstring, strcspn(vstring, "\r\n"));
1044 sprintf(vstring, "%s\n", verstring);
1045 sprintf(vlog, "We claim version: %s", verstring);
1046 logevent(vlog);
1047 logevent("Using SSH protocol version 2");
1048 s_write(vstring, strlen(vstring));
1049 ssh_protocol = ssh2_protocol;
6abbf9e3 1050 ssh_version = 2;
e5574168 1051 s_rdpkt = ssh2_rdpkt;
1052 } else {
1053 /*
1054 * This is a v1 server. Begin v1 protocol.
1055 */
1056 sprintf(vstring, "SSH-%s-PuTTY\n",
1057 (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5"));
1058 sprintf(vlog, "We claim version: %s", vstring);
1059 vlog[strcspn(vlog, "\r\n")] = '\0';
1060 logevent(vlog);
1061 logevent("Using SSH protocol version 1");
1062 s_write(vstring, strlen(vstring));
1063 ssh_protocol = ssh1_protocol;
6abbf9e3 1064 ssh_version = 1;
e5574168 1065 s_rdpkt = ssh1_rdpkt;
1066 }
8ccc75b0 1067 ssh_send_ok = 0;
fef97f43 1068 return 1;
374330e2 1069}
1070
fb09bf1c 1071/*
1072 * Handle the key exchange and user authentication phases.
1073 */
e5574168 1074static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
fb09bf1c 1075{
374330e2 1076 int i, j, len;
374330e2 1077 unsigned char *rsabuf, *keystr1, *keystr2;
1078 unsigned char cookie[8];
1079 struct RSAKey servkey, hostkey;
1080 struct MD5Context md5c;
ccbfb941 1081 static unsigned long supported_ciphers_mask, supported_auths_mask;
7cca0d81 1082 static int tried_publickey;
1083 static unsigned char session_id[16];
bea1ef5f 1084 int cipher_type;
374330e2 1085
374330e2 1086 crBegin;
1087
fb09bf1c 1088 if (!ispkt) crWaitUntil(ispkt);
374330e2 1089
8d5de777 1090 if (pktin.type != SSH1_SMSG_PUBLIC_KEY) {
1091 bombout(("Public key packet not received"));
1092 crReturn(0);
1093 }
374330e2 1094
c5e9c988 1095 logevent("Received public keys");
374330e2 1096
c5e9c988 1097 memcpy(cookie, pktin.body, 8);
374330e2 1098
7cca0d81 1099 i = makekey(pktin.body+8, &servkey, &keystr1, 0);
1100 j = makekey(pktin.body+8+i, &hostkey, &keystr2, 0);
374330e2 1101
c5e9c988 1102 /*
1103 * Hash the host key and print the hash in the log box. Just as
1104 * a last resort in case the registry's host key checking is
1105 * compromised, we'll allow the user some ability to verify
1106 * host keys by eye.
1107 */
1108 MD5Init(&md5c);
1109 MD5Update(&md5c, keystr2, hostkey.bytes);
1110 MD5Final(session_id, &md5c);
1111 {
1112 char logmsg[80];
1113 int i;
1114 logevent("Host key MD5 is:");
1115 strcpy(logmsg, " ");
1116 for (i = 0; i < 16; i++)
1117 sprintf(logmsg+strlen(logmsg), "%02x", session_id[i]);
1118 logevent(logmsg);
1119 }
1120
fb09bf1c 1121 supported_ciphers_mask = GET_32BIT(pktin.body+12+i+j);
1122 supported_auths_mask = GET_32BIT(pktin.body+16+i+j);
bea1ef5f 1123
c5e9c988 1124 MD5Init(&md5c);
374330e2 1125 MD5Update(&md5c, keystr2, hostkey.bytes);
1126 MD5Update(&md5c, keystr1, servkey.bytes);
1127 MD5Update(&md5c, pktin.body, 8);
374330e2 1128 MD5Final(session_id, &md5c);
1129
1130 for (i=0; i<32; i++)
1131 session_key[i] = random_byte();
1132
1133 len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
1134
1135 rsabuf = malloc(len);
1136 if (!rsabuf)
1137 fatalbox("Out of memory");
1138
89ee5268 1139 /*
1140 * Verify the host key.
1141 */
1142 {
1143 /*
1144 * First format the key into a string.
1145 */
1146 int len = rsastr_len(&hostkey);
1147 char *keystr = malloc(len);
1148 if (!keystr)
1149 fatalbox("Out of memory");
1150 rsastr_fmt(keystr, &hostkey);
1151 verify_ssh_host_key(savedhost, keystr);
1152 free(keystr);
1153 }
374330e2 1154
1155 for (i=0; i<32; i++) {
1156 rsabuf[i] = session_key[i];
1157 if (i < 16)
1158 rsabuf[i] ^= session_id[i];
1159 }
1160
1161 if (hostkey.bytes > servkey.bytes) {
1162 rsaencrypt(rsabuf, 32, &servkey);
1163 rsaencrypt(rsabuf, servkey.bytes, &hostkey);
1164 } else {
1165 rsaencrypt(rsabuf, 32, &hostkey);
1166 rsaencrypt(rsabuf, hostkey.bytes, &servkey);
1167 }
1168
c5e9c988 1169 logevent("Encrypted session key");
1170
bea1ef5f 1171 cipher_type = cfg.cipher == CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH :
9697bfd2 1172 cfg.cipher == CIPHER_DES ? SSH_CIPHER_DES :
bea1ef5f 1173 SSH_CIPHER_3DES;
1174 if ((supported_ciphers_mask & (1 << cipher_type)) == 0) {
1175 c_write("Selected cipher not supported, falling back to 3DES\r\n", 53);
1176 cipher_type = SSH_CIPHER_3DES;
1177 }
c5e9c988 1178 switch (cipher_type) {
1179 case SSH_CIPHER_3DES: logevent("Using 3DES encryption"); break;
1180 case SSH_CIPHER_DES: logevent("Using single-DES encryption"); break;
1181 case SSH_CIPHER_BLOWFISH: logevent("Using Blowfish encryption"); break;
1182 }
bea1ef5f 1183
e5574168 1184 send_packet(SSH1_CMSG_SESSION_KEY,
fb09bf1c 1185 PKT_CHAR, cipher_type,
1186 PKT_DATA, cookie, 8,
1187 PKT_CHAR, (len*8) >> 8, PKT_CHAR, (len*8) & 0xFF,
1188 PKT_DATA, rsabuf, len,
1189 PKT_INT, 0,
1190 PKT_END);
1191
c5e9c988 1192 logevent("Trying to enable encryption...");
374330e2 1193
1194 free(rsabuf);
1195
5e8358ad 1196 cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
9697bfd2 1197 cipher_type == SSH_CIPHER_DES ? &ssh_des :
bea1ef5f 1198 &ssh_3des;
374330e2 1199 cipher->sesskey(session_key);
1200
fb09bf1c 1201 crWaitUntil(ispkt);
374330e2 1202
8d5de777 1203 if (pktin.type != SSH1_SMSG_SUCCESS) {
1204 bombout(("Encryption not successfully enabled"));
1205 crReturn(0);
1206 }
374330e2 1207
c5e9c988 1208 logevent("Successfully started encryption");
1209
374330e2 1210 fflush(stdout);
1211 {
1212 static char username[100];
1213 static int pos = 0;
1214 static char c;
67779be7 1215 if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
374330e2 1216 c_write("login as: ", 10);
67779be7 1217 ssh_send_ok = 1;
374330e2 1218 while (pos >= 0) {
fb09bf1c 1219 crWaitUntil(!ispkt);
374330e2 1220 while (inlen--) switch (c = *in++) {
1221 case 10: case 13:
1222 username[pos] = 0;
1223 pos = -1;
1224 break;
1225 case 8: case 127:
1226 if (pos > 0) {
1227 c_write("\b \b", 3);
1228 pos--;
1229 }
1230 break;
1231 case 21: case 27:
1232 while (pos > 0) {
1233 c_write("\b \b", 3);
1234 pos--;
1235 }
1236 break;
1237 case 3: case 4:
1238 random_save_seed();
1239 exit(0);
1240 break;
1241 default:
40d24aa6 1242 if (((c >= ' ' && c <= '~') ||
1243 ((unsigned char)c >= 160)) && pos < 40) {
374330e2 1244 username[pos++] = c;
1245 c_write(&c, 1);
1246 }
1247 break;
1248 }
1249 }
1250 c_write("\r\n", 2);
1251 username[strcspn(username, "\n\r")] = '\0';
1252 } else {
1253 char stuff[200];
1254 strncpy(username, cfg.username, 99);
1255 username[99] = '\0';
67779be7 1256 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
fb09bf1c 1257 sprintf(stuff, "Sent username \"%s\".\r\n", username);
4017be6d 1258 c_write(stuff, strlen(stuff));
fb09bf1c 1259 }
374330e2 1260 }
fb09bf1c 1261
e5574168 1262 send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END);
c5e9c988 1263 {
1264 char userlog[20+sizeof(username)];
1265 sprintf(userlog, "Sent username \"%s\"", username);
1266 logevent(userlog);
1267 }
374330e2 1268 }
1269
fb09bf1c 1270 crWaitUntil(ispkt);
374330e2 1271
7cca0d81 1272 tried_publickey = 0;
1273
e5574168 1274 while (pktin.type == SSH1_SMSG_FAILURE) {
374330e2 1275 static char password[100];
1276 static int pos;
1277 static char c;
ccbfb941 1278 static int pwpkt_type;
ccbfb941 1279 /*
1280 * Show password prompt, having first obtained it via a TIS
18515c51 1281 * or CryptoCard exchange if we're doing TIS or CryptoCard
1282 * authentication.
ccbfb941 1283 */
e5574168 1284 pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
5c58ad2d 1285 if (agent_exists()) {
1286 /*
1287 * Attempt RSA authentication using Pageant.
1288 */
1289 static unsigned char request[5], *response, *p;
1290 static int responselen;
1291 static int i, nkeys;
1292 static int authed = FALSE;
1293 void *r;
1294
1295 logevent("Pageant is running. Requesting keys.");
1296
1297 /* Request the keys held by the agent. */
1298 PUT_32BIT(request, 1);
1299 request[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES;
1300 agent_query(request, 5, &r, &responselen);
1301 response = (unsigned char *)r;
1302 if (response) {
1303 p = response + 5;
1304 nkeys = GET_32BIT(p); p += 4;
1305 { char buf[64]; sprintf(buf, "Pageant has %d keys", nkeys);
1306 logevent(buf); }
1307 for (i = 0; i < nkeys; i++) {
1308 static struct RSAKey key;
1309 static Bignum challenge;
b8bb811a 1310 static char *commentp;
1311 static int commentlen;
5c58ad2d 1312
1313 { char buf[64]; sprintf(buf, "Trying Pageant key #%d", i);
1314 logevent(buf); }
1315 p += 4;
1316 p += ssh1_read_bignum(p, &key.exponent);
1317 p += ssh1_read_bignum(p, &key.modulus);
b8bb811a 1318 commentlen = GET_32BIT(p); p += 4;
1319 commentp = p; p += commentlen;
5c58ad2d 1320 send_packet(SSH1_CMSG_AUTH_RSA,
1321 PKT_BIGNUM, key.modulus, PKT_END);
1322 crWaitUntil(ispkt);
1323 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
1324 logevent("Key refused");
1325 continue;
1326 }
1327 logevent("Received RSA challenge");
1328 ssh1_read_bignum(pktin.body, &challenge);
1329 {
1330 char *agentreq, *q, *ret;
1331 int len, retlen;
1332 len = 1 + 4; /* message type, bit count */
1333 len += ssh1_bignum_length(key.exponent);
1334 len += ssh1_bignum_length(key.modulus);
1335 len += ssh1_bignum_length(challenge);
1336 len += 16; /* session id */
1337 len += 4; /* response format */
1338 agentreq = malloc(4 + len);
1339 PUT_32BIT(agentreq, len);
1340 q = agentreq + 4;
1341 *q++ = SSH_AGENTC_RSA_CHALLENGE;
1342 PUT_32BIT(q, ssh1_bignum_bitcount(key.modulus));
1343 q += 4;
1344 q += ssh1_write_bignum(q, key.exponent);
1345 q += ssh1_write_bignum(q, key.modulus);
1346 q += ssh1_write_bignum(q, challenge);
1347 memcpy(q, session_id, 16); q += 16;
1348 PUT_32BIT(q, 1); /* response format */
1349 agent_query(agentreq, len+4, &ret, &retlen);
1350 free(agentreq);
1351 if (ret) {
1352 if (ret[4] == SSH_AGENT_RSA_RESPONSE) {
1353 logevent("Sending Pageant's response");
1354 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
1355 PKT_DATA, ret+5, 16, PKT_END);
1356 free(ret);
1357 crWaitUntil(ispkt);
1358 if (pktin.type == SSH1_SMSG_SUCCESS) {
1359 logevent("Pageant's response accepted");
b8bb811a 1360 c_write("Authenticated using RSA key \"",
1361 29);
1362 c_write(commentp, commentlen);
1363 c_write("\" from agent\r\n", 14);
5c58ad2d 1364 authed = TRUE;
1365 } else
1366 logevent("Pageant's response not accepted");
1367 } else {
1368 logevent("Pageant failed to answer challenge");
1369 free(ret);
1370 }
1371 } else {
1372 logevent("No reply received from Pageant");
1373 }
1374 }
1375 freebn(key.exponent);
1376 freebn(key.modulus);
1377 freebn(challenge);
1378 if (authed)
1379 break;
1380 }
1381 }
1382 if (authed)
1383 break;
1384 }
7cca0d81 1385 if (*cfg.keyfile && !tried_publickey)
1386 pwpkt_type = SSH1_CMSG_AUTH_RSA;
fb09bf1c 1387
67779be7 1388 if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD &&
1389 !(flags & FLAG_INTERACTIVE)) {
fb09bf1c 1390 char prompt[200];
1391 sprintf(prompt, "%s@%s's password: ", cfg.username, savedhost);
85ee8208 1392 if (!ssh_get_password(prompt, password, sizeof(password))) {
1393 /*
1394 * get_password failed to get a password (for
1395 * example because one was supplied on the command
1396 * line which has already failed to work).
1397 * Terminate.
1398 */
1399 logevent("No more passwords to try");
1400 ssh_state = SSH_STATE_CLOSED;
1401 crReturn(1);
1402 }
fb09bf1c 1403 } else {
1404
7cca0d81 1405 if (pktin.type == SSH1_SMSG_FAILURE &&
1406 cfg.try_tis_auth &&
1407 (supported_auths_mask & (1<<SSH1_AUTH_TIS))) {
1408 pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
1409 logevent("Requested TIS authentication");
1410 send_packet(SSH1_CMSG_AUTH_TIS, PKT_END);
1411 crWaitUntil(ispkt);
1412 if (pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
1413 logevent("TIS authentication declined");
1414 c_write("TIS authentication refused.\r\n", 29);
1415 } else {
1416 int challengelen = ((pktin.body[0] << 24) |
1417 (pktin.body[1] << 16) |
1418 (pktin.body[2] << 8) |
1419 (pktin.body[3]));
1420 logevent("Received TIS challenge");
1421 c_write(pktin.body+4, challengelen);
1422 }
1423 }
18515c51 1424 if (pktin.type == SSH1_SMSG_FAILURE &&
1425 cfg.try_tis_auth &&
1426 (supported_auths_mask & (1<<SSH1_AUTH_CCARD))) {
1427 pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
1428 logevent("Requested CryptoCard authentication");
1429 send_packet(SSH1_CMSG_AUTH_CCARD, PKT_END);
1430 crWaitUntil(ispkt);
1431 if (pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
1432 logevent("CryptoCard authentication declined");
1433 c_write("CryptoCard authentication refused.\r\n", 29);
1434 } else {
1435 int challengelen = ((pktin.body[0] << 24) |
1436 (pktin.body[1] << 16) |
1437 (pktin.body[2] << 8) |
1438 (pktin.body[3]));
1439 logevent("Received CryptoCard challenge");
1440 c_write(pktin.body+4, challengelen);
1441 c_write("\r\nResponse : ", 13);
1442 }
1443 }
7cca0d81 1444 if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD)
1445 c_write("password: ", 10);
1446 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
4017be6d 1447 if (flags & FLAG_VERBOSE)
1448 c_write("Trying public key authentication.\r\n", 35);
7cca0d81 1449 if (!rsakey_encrypted(cfg.keyfile)) {
4017be6d 1450 if (flags & FLAG_VERBOSE)
1451 c_write("No passphrase required.\r\n", 25);
7cca0d81 1452 goto tryauth;
1453 }
1454 c_write("passphrase: ", 12);
ccbfb941 1455 }
ccbfb941 1456
7cca0d81 1457 pos = 0;
67779be7 1458 ssh_send_ok = 1;
7cca0d81 1459 while (pos >= 0) {
1460 crWaitUntil(!ispkt);
1461 while (inlen--) switch (c = *in++) {
1462 case 10: case 13:
1463 password[pos] = 0;
1464 pos = -1;
1465 break;
1466 case 8: case 127:
1467 if (pos > 0)
1468 pos--;
1469 break;
1470 case 21: case 27:
1471 pos = 0;
1472 break;
1473 case 3: case 4:
1474 random_save_seed();
1475 exit(0);
1476 break;
1477 default:
1478 if (((c >= ' ' && c <= '~') ||
1479 ((unsigned char)c >= 160)) && pos < sizeof(password))
1480 password[pos++] = c;
1481 break;
1482 }
1483 }
1484 c_write("\r\n", 2);
fb09bf1c 1485
1486 }
1487
7cca0d81 1488 tryauth:
1489 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
1490 /*
1491 * Try public key authentication with the specified
1492 * key file.
1493 */
1494 static struct RSAKey pubkey;
1495 static Bignum challenge, response;
1496 static int i;
1497 static unsigned char buffer[32];
1498
1499 tried_publickey = 1;
1500 i = loadrsakey(cfg.keyfile, &pubkey, password);
1501 if (i == 0) {
1502 c_write("Couldn't load public key from ", 30);
1503 c_write(cfg.keyfile, strlen(cfg.keyfile));
1504 c_write(".\r\n", 3);
1505 continue; /* go and try password */
1506 }
1507 if (i == -1) {
1508 c_write("Wrong passphrase.\r\n", 19);
1509 tried_publickey = 0;
1510 continue; /* try again */
1511 }
1512
1513 /*
1514 * Send a public key attempt.
1515 */
1516 send_packet(SSH1_CMSG_AUTH_RSA,
1517 PKT_BIGNUM, pubkey.modulus, PKT_END);
1518
1519 crWaitUntil(ispkt);
1520 if (pktin.type == SSH1_SMSG_FAILURE) {
4017be6d 1521 if (flags & FLAG_VERBOSE)
1522 c_write("Server refused our public key.\r\n", 32);
7cca0d81 1523 continue; /* go and try password */
1524 }
8d5de777 1525 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
1526 bombout(("Bizarre response to offer of public key"));
1527 crReturn(0);
1528 }
7cca0d81 1529 ssh1_read_bignum(pktin.body, &challenge);
1530 response = rsadecrypt(challenge, &pubkey);
1531 freebn(pubkey.private_exponent); /* burn the evidence */
1532
1533 for (i = 0; i < 32; i += 2) {
1534 buffer[i] = response[16-i/2] >> 8;
1535 buffer[i+1] = response[16-i/2] & 0xFF;
1536 }
1537
1538 MD5Init(&md5c);
1539 MD5Update(&md5c, buffer, 32);
1540 MD5Update(&md5c, session_id, 16);
1541 MD5Final(buffer, &md5c);
1542
1543 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
1544 PKT_DATA, buffer, 16, PKT_END);
1545
1546 crWaitUntil(ispkt);
1547 if (pktin.type == SSH1_SMSG_FAILURE) {
4017be6d 1548 if (flags & FLAG_VERBOSE)
1549 c_write("Failed to authenticate with our public key.\r\n",
1550 45);
7cca0d81 1551 continue; /* go and try password */
1552 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
8d5de777 1553 bombout(("Bizarre response to RSA authentication response"));
1554 crReturn(0);
7cca0d81 1555 }
1556
1557 break; /* we're through! */
1558 } else {
1559 send_packet(pwpkt_type, PKT_STR, password, PKT_END);
1560 }
c5e9c988 1561 logevent("Sent password");
374330e2 1562 memset(password, 0, strlen(password));
fb09bf1c 1563 crWaitUntil(ispkt);
e5574168 1564 if (pktin.type == SSH1_SMSG_FAILURE) {
4017be6d 1565 if (flags & FLAG_VERBOSE)
1566 c_write("Access denied\r\n", 15);
c5e9c988 1567 logevent("Authentication refused");
e5574168 1568 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
fb09bf1c 1569 logevent("Received disconnect request");
85ee8208 1570 ssh_state = SSH_STATE_CLOSED;
1571 crReturn(1);
e5574168 1572 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
8d5de777 1573 bombout(("Strange packet received, type %d", pktin.type));
1574 crReturn(0);
374330e2 1575 }
1576 }
1577
c5e9c988 1578 logevent("Authentication successful");
1579
fb09bf1c 1580 crFinish(1);
1581}
1582
e5574168 1583static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) {
fb09bf1c 1584 crBegin;
1585
1586 random_init();
1587
e5574168 1588 while (!do_ssh1_login(in, inlen, ispkt)) {
fb09bf1c 1589 crReturnV;
85ee8208 1590 }
1591 if (ssh_state == SSH_STATE_CLOSED)
1592 crReturnV;
fb09bf1c 1593
979310f1 1594 if (cfg.agentfwd && agent_exists()) {
dacbd0e8 1595 logevent("Requesting agent forwarding");
1596 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
1597 do { crReturnV; } while (!ispkt);
1598 if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
8d5de777 1599 bombout(("Protocol confusion"));
1600 crReturnV;
dacbd0e8 1601 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1602 logevent("Agent forwarding refused");
1603 } else
1604 logevent("Agent forwarding enabled");
1605 }
1606
fef97f43 1607 if (!cfg.nopty) {
e5574168 1608 send_packet(SSH1_CMSG_REQUEST_PTY,
fb09bf1c 1609 PKT_STR, cfg.termtype,
1610 PKT_INT, rows, PKT_INT, cols,
1611 PKT_INT, 0, PKT_INT, 0,
1612 PKT_CHAR, 0,
1613 PKT_END);
fef97f43 1614 ssh_state = SSH_STATE_INTERMED;
1615 do { crReturnV; } while (!ispkt);
e5574168 1616 if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
8d5de777 1617 bombout(("Protocol confusion"));
1618 crReturnV;
e5574168 1619 } else if (pktin.type == SSH1_SMSG_FAILURE) {
fef97f43 1620 c_write("Server refused to allocate pty\r\n", 32);
1621 }
c5e9c988 1622 logevent("Allocated pty");
374330e2 1623 }
1624
6abbf9e3 1625 if (*cfg.remote_cmd)
1626 send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cfg.remote_cmd, PKT_END);
1627 else
1628 send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END);
c5e9c988 1629 logevent("Started session");
374330e2 1630
1631 ssh_state = SSH_STATE_SESSION;
1632 if (size_needed)
1633 ssh_size();
1634
8ccc75b0 1635 ssh_send_ok = 1;
dacbd0e8 1636 ssh_channels = newtree234(ssh_channelcmp);
6f34e365 1637 begin_session();
374330e2 1638 while (1) {
1639 crReturnV;
1640 if (ispkt) {
e5574168 1641 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
1642 pktin.type == SSH1_SMSG_STDERR_DATA) {
fb09bf1c 1643 long len = GET_32BIT(pktin.body);
1644 c_write(pktin.body+4, len);
e5574168 1645 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
21248260 1646 ssh_state = SSH_STATE_CLOSED;
c5e9c988 1647 logevent("Received disconnect request");
dacbd0e8 1648 } else if (pktin.type == SSH1_SMSG_AGENT_OPEN) {
1649 /* Remote side is trying to open a channel to talk to our
1650 * agent. Give them back a local channel number. */
d211621f 1651 unsigned i = 1;
dacbd0e8 1652 struct ssh_channel *c;
1653 enum234 e;
1654 for (c = first234(ssh_channels, &e); c; c = next234(&e)) {
1655 if (c->localid > i)
1656 break; /* found a free number */
1657 i = c->localid + 1;
1658 }
1659 c = malloc(sizeof(struct ssh_channel));
1660 c->remoteid = GET_32BIT(pktin.body);
1661 c->localid = i;
b8bb811a 1662 c->closes = 0;
dacbd0e8 1663 c->type = SSH1_SMSG_AGENT_OPEN; /* identify channel type */
1664 add234(ssh_channels, c);
1665 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
1666 PKT_INT, c->remoteid, PKT_INT, c->localid,
1667 PKT_END);
1668 } else if (pktin.type == SSH1_MSG_CHANNEL_CLOSE ||
1669 pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
1670 /* Remote side closes a channel. */
d211621f 1671 unsigned i = GET_32BIT(pktin.body);
dacbd0e8 1672 struct ssh_channel *c;
1673 c = find234(ssh_channels, &i, ssh_channelfind);
1674 if (c) {
1675 int closetype;
1676 closetype = (pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
1677 send_packet(pktin.type, PKT_INT, c->remoteid, PKT_END);
1678 c->closes |= closetype;
1679 if (c->closes == 3) {
1680 del234(ssh_channels, c);
1681 free(c);
1682 }
1683 }
1684 } else if (pktin.type == SSH1_MSG_CHANNEL_DATA) {
1685 /* Data sent down one of our channels. */
1686 int i = GET_32BIT(pktin.body);
1687 int len = GET_32BIT(pktin.body+4);
1688 unsigned char *p = pktin.body+8;
1689 struct ssh_channel *c;
1690 c = find234(ssh_channels, &i, ssh_channelfind);
1691 if (c) {
1692 switch(c->type) {
1693 case SSH1_SMSG_AGENT_OPEN:
1694 /* Data for an agent message. Buffer it. */
1695 while (len > 0) {
1696 if (c->u.a.lensofar < 4) {
1697 int l = min(4 - c->u.a.lensofar, len);
1698 memcpy(c->u.a.msglen + c->u.a.lensofar, p, l);
1699 p += l; len -= l; c->u.a.lensofar += l;
1700 }
1701 if (c->u.a.lensofar == 4) {
1702 c->u.a.totallen = 4 + GET_32BIT(c->u.a.msglen);
1703 c->u.a.message = malloc(c->u.a.totallen);
1704 memcpy(c->u.a.message, c->u.a.msglen, 4);
1705 }
1706 if (c->u.a.lensofar >= 4 && len > 0) {
1707 int l = min(c->u.a.totallen - c->u.a.lensofar, len);
1708 memcpy(c->u.a.message + c->u.a.lensofar, p, l);
1709 p += l; len -= l; c->u.a.lensofar += l;
1710 }
1711 if (c->u.a.lensofar == c->u.a.totallen) {
1712 void *reply, *sentreply;
1713 int replylen;
1714 agent_query(c->u.a.message, c->u.a.totallen,
1715 &reply, &replylen);
1716 if (reply)
1717 sentreply = reply;
1718 else {
1719 /* Fake SSH_AGENT_FAILURE. */
1720 sentreply = "\0\0\0\1\5";
1721 replylen = 5;
1722 }
1723 send_packet(SSH1_MSG_CHANNEL_DATA,
1724 PKT_INT, c->remoteid,
1725 PKT_INT, replylen,
1726 PKT_DATA, sentreply, replylen,
1727 PKT_END);
1728 if (reply)
1729 free(reply);
1730 free(c->u.a.message);
1731 c->u.a.lensofar = 0;
1732 }
1733 }
1734 break;
1735 }
1736 }
e5574168 1737 } else if (pktin.type == SSH1_SMSG_SUCCESS) {
972a41c8 1738 /* may be from EXEC_SHELL on some servers */
e5574168 1739 } else if (pktin.type == SSH1_SMSG_FAILURE) {
972a41c8 1740 /* may be from EXEC_SHELL on some servers
374330e2 1741 * if no pty is available or in other odd cases. Ignore */
e5574168 1742 } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) {
1743 send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
374330e2 1744 } else {
8d5de777 1745 bombout(("Strange packet received: type %d", pktin.type));
1746 crReturnV;
374330e2 1747 }
1748 } else {
e5574168 1749 send_packet(SSH1_CMSG_STDIN_DATA,
fb09bf1c 1750 PKT_INT, inlen, PKT_DATA, in, inlen, PKT_END);
374330e2 1751 }
1752 }
1753
1754 crFinishV;
1755}
1756
1757/*
e5574168 1758 * Utility routine for decoding comma-separated strings in KEXINIT.
1759 */
1760int in_commasep_string(char *needle, char *haystack, int haylen) {
1761 int needlen = strlen(needle);
1762 while (1) {
1763 /*
1764 * Is it at the start of the string?
1765 */
1766 if (haylen >= needlen && /* haystack is long enough */
1767 !memcmp(needle, haystack, needlen) && /* initial match */
1768 (haylen == needlen || haystack[needlen] == ',')
1769 /* either , or EOS follows */
1770 )
1771 return 1;
1772 /*
1773 * If not, search for the next comma and resume after that.
1774 * If no comma found, terminate.
1775 */
1776 while (haylen > 0 && *haystack != ',')
1777 haylen--, haystack++;
1778 if (haylen == 0)
1779 return 0;
1780 haylen--, haystack++; /* skip over comma itself */
1781 }
1782}
1783
1784/*
d39f364a 1785 * SSH2 key creation method.
1786 */
1787void ssh2_mkkey(Bignum K, char *H, char chr, char *keyspace) {
1788 SHA_State s;
1789 /* First 20 bytes. */
1790 SHA_Init(&s);
1791 sha_mpint(&s, K);
1792 SHA_Bytes(&s, H, 20);
1793 SHA_Bytes(&s, &chr, 1);
1794 SHA_Bytes(&s, H, 20);
1795 SHA_Final(&s, keyspace);
1796 /* Next 20 bytes. */
1797 SHA_Init(&s);
1798 sha_mpint(&s, K);
1799 SHA_Bytes(&s, H, 20);
1800 SHA_Bytes(&s, keyspace, 20);
1801 SHA_Final(&s, keyspace+20);
1802}
1803
1804/*
7cca0d81 1805 * Handle the SSH2 transport layer.
e5574168 1806 */
7cca0d81 1807static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt)
e5574168 1808{
1809 static int i, len;
1810 static char *str;
1811 static Bignum e, f, K;
1812 static struct ssh_cipher *cscipher_tobe = NULL;
1813 static struct ssh_cipher *sccipher_tobe = NULL;
1814 static struct ssh_mac *csmac_tobe = NULL;
1815 static struct ssh_mac *scmac_tobe = NULL;
1816 static struct ssh_compress *cscomp_tobe = NULL;
1817 static struct ssh_compress *sccomp_tobe = NULL;
7cca0d81 1818 static char *hostkeydata, *sigdata, *keystr;
e5574168 1819 static int hostkeylen, siglen;
1820 static unsigned char exchange_hash[20];
d39f364a 1821 static unsigned char keyspace[40];
e5574168 1822
1823 crBegin;
7cca0d81 1824 random_init();
e5574168 1825
5e8358ad 1826 /*
1827 * Set up the preferred cipher.
1828 */
1829 if (cfg.cipher == CIPHER_BLOWFISH) {
1830 ciphers[0] = &ssh_blowfish_ssh2;
1831 } else if (cfg.cipher == CIPHER_DES) {
1832 logevent("Single DES not supported in SSH2; using 3DES");
1833 ciphers[0] = &ssh_3des_ssh2;
1834 } else if (cfg.cipher == CIPHER_3DES) {
1835 ciphers[0] = &ssh_3des_ssh2;
1836 } else {
1837 /* Shouldn't happen, but we do want to initialise to _something_. */
1838 ciphers[0] = &ssh_3des_ssh2;
1839 }
1840
7cca0d81 1841 begin_key_exchange:
e5574168 1842 /*
1843 * Construct and send our key exchange packet.
1844 */
1845 ssh2_pkt_init(SSH2_MSG_KEXINIT);
1846 for (i = 0; i < 16; i++)
1847 ssh2_pkt_addbyte((unsigned char)random_byte());
1848 /* List key exchange algorithms. */
1849 ssh2_pkt_addstring_start();
1850 for (i = 0; i < lenof(kex_algs); i++) {
1851 ssh2_pkt_addstring_str(kex_algs[i]->name);
1852 if (i < lenof(kex_algs)-1)
1853 ssh2_pkt_addstring_str(",");
1854 }
1855 /* List server host key algorithms. */
1856 ssh2_pkt_addstring_start();
1857 for (i = 0; i < lenof(hostkey_algs); i++) {
1858 ssh2_pkt_addstring_str(hostkey_algs[i]->name);
1859 if (i < lenof(hostkey_algs)-1)
1860 ssh2_pkt_addstring_str(",");
1861 }
1862 /* List client->server encryption algorithms. */
1863 ssh2_pkt_addstring_start();
1864 for (i = 0; i < lenof(ciphers); i++) {
1865 ssh2_pkt_addstring_str(ciphers[i]->name);
1866 if (i < lenof(ciphers)-1)
1867 ssh2_pkt_addstring_str(",");
1868 }
1869 /* List server->client encryption algorithms. */
1870 ssh2_pkt_addstring_start();
1871 for (i = 0; i < lenof(ciphers); i++) {
1872 ssh2_pkt_addstring_str(ciphers[i]->name);
1873 if (i < lenof(ciphers)-1)
1874 ssh2_pkt_addstring_str(",");
1875 }
1876 /* List client->server MAC algorithms. */
1877 ssh2_pkt_addstring_start();
1878 for (i = 0; i < lenof(macs); i++) {
1879 ssh2_pkt_addstring_str(macs[i]->name);
1880 if (i < lenof(macs)-1)
1881 ssh2_pkt_addstring_str(",");
1882 }
1883 /* List server->client MAC algorithms. */
1884 ssh2_pkt_addstring_start();
1885 for (i = 0; i < lenof(macs); i++) {
1886 ssh2_pkt_addstring_str(macs[i]->name);
1887 if (i < lenof(macs)-1)
1888 ssh2_pkt_addstring_str(",");
1889 }
1890 /* List client->server compression algorithms. */
1891 ssh2_pkt_addstring_start();
1892 for (i = 0; i < lenof(compressions); i++) {
1893 ssh2_pkt_addstring_str(compressions[i]->name);
1894 if (i < lenof(compressions)-1)
1895 ssh2_pkt_addstring_str(",");
1896 }
1897 /* List server->client compression algorithms. */
1898 ssh2_pkt_addstring_start();
1899 for (i = 0; i < lenof(compressions); i++) {
1900 ssh2_pkt_addstring_str(compressions[i]->name);
1901 if (i < lenof(compressions)-1)
1902 ssh2_pkt_addstring_str(",");
1903 }
1904 /* List client->server languages. Empty list. */
1905 ssh2_pkt_addstring_start();
1906 /* List server->client languages. Empty list. */
1907 ssh2_pkt_addstring_start();
1908 /* First KEX packet does _not_ follow, because we're not that brave. */
1909 ssh2_pkt_addbool(FALSE);
1910 /* Reserved. */
1911 ssh2_pkt_adduint32(0);
1912 sha_string(&exhash, pktout.data+5, pktout.length-5);
1913 ssh2_pkt_send();
1914
1915 if (!ispkt) crWaitUntil(ispkt);
1916 sha_string(&exhash, pktin.data+5, pktin.length-5);
1917
1918 /*
1919 * Now examine the other side's KEXINIT to see what we're up
1920 * to.
1921 */
7cca0d81 1922 if (pktin.type != SSH2_MSG_KEXINIT) {
8d5de777 1923 bombout(("expected key exchange packet from server"));
1924 crReturn(0);
7cca0d81 1925 }
e5574168 1926 kex = NULL; hostkey = NULL; cscipher_tobe = NULL; sccipher_tobe = NULL;
1927 csmac_tobe = NULL; scmac_tobe = NULL; cscomp_tobe = NULL; sccomp_tobe = NULL;
1928 pktin.savedpos += 16; /* skip garbage cookie */
1929 ssh2_pkt_getstring(&str, &len); /* key exchange algorithms */
1930 for (i = 0; i < lenof(kex_algs); i++) {
1931 if (in_commasep_string(kex_algs[i]->name, str, len)) {
1932 kex = kex_algs[i];
1933 break;
1934 }
1935 }
1936 ssh2_pkt_getstring(&str, &len); /* host key algorithms */
1937 for (i = 0; i < lenof(hostkey_algs); i++) {
1938 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
1939 hostkey = hostkey_algs[i];
1940 break;
1941 }
1942 }
1943 ssh2_pkt_getstring(&str, &len); /* client->server cipher */
1944 for (i = 0; i < lenof(ciphers); i++) {
1945 if (in_commasep_string(ciphers[i]->name, str, len)) {
1946 cscipher_tobe = ciphers[i];
1947 break;
1948 }
1949 }
1950 ssh2_pkt_getstring(&str, &len); /* server->client cipher */
1951 for (i = 0; i < lenof(ciphers); i++) {
1952 if (in_commasep_string(ciphers[i]->name, str, len)) {
1953 sccipher_tobe = ciphers[i];
1954 break;
1955 }
1956 }
1957 ssh2_pkt_getstring(&str, &len); /* client->server mac */
1958 for (i = 0; i < lenof(macs); i++) {
1959 if (in_commasep_string(macs[i]->name, str, len)) {
1960 csmac_tobe = macs[i];
1961 break;
1962 }
1963 }
1964 ssh2_pkt_getstring(&str, &len); /* server->client mac */
1965 for (i = 0; i < lenof(macs); i++) {
1966 if (in_commasep_string(macs[i]->name, str, len)) {
1967 scmac_tobe = macs[i];
1968 break;
1969 }
1970 }
1971 ssh2_pkt_getstring(&str, &len); /* client->server compression */
1972 for (i = 0; i < lenof(compressions); i++) {
1973 if (in_commasep_string(compressions[i]->name, str, len)) {
1974 cscomp_tobe = compressions[i];
1975 break;
1976 }
1977 }
1978 ssh2_pkt_getstring(&str, &len); /* server->client compression */
1979 for (i = 0; i < lenof(compressions); i++) {
1980 if (in_commasep_string(compressions[i]->name, str, len)) {
1981 sccomp_tobe = compressions[i];
1982 break;
1983 }
1984 }
e5574168 1985
1986 /*
1987 * Currently we only support Diffie-Hellman and DSS, so let's
1988 * bomb out if those aren't selected.
1989 */
8d5de777 1990 if (kex != &ssh_diffiehellman || hostkey != &ssh_dss) {
1991 bombout(("internal fault: chaos in SSH 2 transport layer"));
1992 crReturn(0);
1993 }
e5574168 1994
1995 /*
1996 * Now we begin the fun. Generate and send e for Diffie-Hellman.
1997 */
1998 e = dh_create_e();
e5574168 1999 ssh2_pkt_init(SSH2_MSG_KEXDH_INIT);
2000 ssh2_pkt_addmp(e);
2001 ssh2_pkt_send();
2002
2003 crWaitUntil(ispkt);
7cca0d81 2004 if (pktin.type != SSH2_MSG_KEXDH_REPLY) {
8d5de777 2005 bombout(("expected key exchange packet from server"));
2006 crReturn(0);
7cca0d81 2007 }
e5574168 2008 ssh2_pkt_getstring(&hostkeydata, &hostkeylen);
2009 f = ssh2_pkt_getmp();
e5574168 2010 ssh2_pkt_getstring(&sigdata, &siglen);
2011
2012 K = dh_find_K(f);
e5574168 2013
2014 sha_string(&exhash, hostkeydata, hostkeylen);
2015 sha_mpint(&exhash, e);
2016 sha_mpint(&exhash, f);
2017 sha_mpint(&exhash, K);
2018 SHA_Final(&exhash, exchange_hash);
2019
7cca0d81 2020#if 0
e5574168 2021 debug(("Exchange hash is:\r\n"));
2022 for (i = 0; i < 20; i++)
2023 debug((" %02x", exchange_hash[i]));
2024 debug(("\r\n"));
7cca0d81 2025#endif
2026
2027 hostkey->setkey(hostkeydata, hostkeylen);
8d5de777 2028 if (!hostkey->verifysig(sigdata, siglen, exchange_hash, 20)) {
2029 bombout(("Server failed host key check"));
2030 crReturn(0);
2031 }
e5574168 2032
2033 /*
7cca0d81 2034 * Expect SSH2_MSG_NEWKEYS from server.
d39f364a 2035 */
7cca0d81 2036 crWaitUntil(ispkt);
8d5de777 2037 if (pktin.type != SSH2_MSG_NEWKEYS) {
2038 bombout(("expected new-keys packet from server"));
2039 crReturn(0);
2040 }
d39f364a 2041
2042 /*
7cca0d81 2043 * Authenticate remote host: verify host key. (We've already
2044 * checked the signature of the exchange hash.)
e5574168 2045 */
7cca0d81 2046 keystr = hostkey->fmtkey();
2047 verify_ssh_host_key(savedhost, keystr);
2048 free(keystr);
d39f364a 2049
2050 /*
7cca0d81 2051 * Send SSH2_MSG_NEWKEYS.
d39f364a 2052 */
2053 ssh2_pkt_init(SSH2_MSG_NEWKEYS);
2054 ssh2_pkt_send();
d39f364a 2055
2056 /*
2057 * Create and initialise session keys.
2058 */
2059 cscipher = cscipher_tobe;
2060 sccipher = sccipher_tobe;
2061 csmac = csmac_tobe;
2062 scmac = scmac_tobe;
2063 cscomp = cscomp_tobe;
2064 sccomp = sccomp_tobe;
2065 /*
2066 * Set IVs after keys.
2067 */
2068 ssh2_mkkey(K, exchange_hash, 'C', keyspace); cscipher->setcskey(keyspace);
2069 ssh2_mkkey(K, exchange_hash, 'D', keyspace); cscipher->setsckey(keyspace);
2070 ssh2_mkkey(K, exchange_hash, 'A', keyspace); cscipher->setcsiv(keyspace);
2071 ssh2_mkkey(K, exchange_hash, 'B', keyspace); sccipher->setsciv(keyspace);
2072 ssh2_mkkey(K, exchange_hash, 'E', keyspace); csmac->setcskey(keyspace);
2073 ssh2_mkkey(K, exchange_hash, 'F', keyspace); scmac->setsckey(keyspace);
2074
033b4cef 2075 /*
7cca0d81 2076 * Now we're encrypting. Begin returning 1 to the protocol main
2077 * function so that other things can run on top of the
2078 * transport. If we ever see a KEXINIT, we must go back to the
2079 * start.
033b4cef 2080 */
7cca0d81 2081 do {
2082 crReturn(1);
2083 } while (!(ispkt && pktin.type == SSH2_MSG_KEXINIT));
2084 goto begin_key_exchange;
e5574168 2085
2086 crFinish(1);
2087}
2088
7cca0d81 2089/*
2090 * Handle the SSH2 userauth and connection layers.
2091 */
2092static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
2093{
7cca0d81 2094 static unsigned long remote_winsize;
2095 static unsigned long remote_maxpkt;
2096
e5574168 2097 crBegin;
2098
7cca0d81 2099 /*
2100 * Request userauth protocol, and await a response to it.
2101 */
2102 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
2103 ssh2_pkt_addstring("ssh-userauth");
2104 ssh2_pkt_send();
2105 crWaitUntilV(ispkt);
8d5de777 2106 if (pktin.type != SSH2_MSG_SERVICE_ACCEPT) {
2107 bombout(("Server refused user authentication protocol"));
2108 crReturnV;
2109 }
7cca0d81 2110
2111 /*
2112 * FIXME: currently we support only password authentication.
2113 * (This places us technically in violation of the SSH2 spec.
2114 * We must fix this.)
2115 */
2116 while (1) {
2117 /*
2118 * Get a username and a password.
2119 */
2120 static char username[100];
2121 static char password[100];
2122 static int pos = 0;
2123 static char c;
e5574168 2124
67779be7 2125 if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
7cca0d81 2126 c_write("login as: ", 10);
67779be7 2127 ssh_send_ok = 1;
7cca0d81 2128 while (pos >= 0) {
2129 crWaitUntilV(!ispkt);
2130 while (inlen--) switch (c = *in++) {
2131 case 10: case 13:
2132 username[pos] = 0;
2133 pos = -1;
2134 break;
2135 case 8: case 127:
2136 if (pos > 0) {
2137 c_write("\b \b", 3);
2138 pos--;
2139 }
2140 break;
2141 case 21: case 27:
2142 while (pos > 0) {
2143 c_write("\b \b", 3);
2144 pos--;
2145 }
2146 break;
2147 case 3: case 4:
2148 random_save_seed();
2149 exit(0);
2150 break;
2151 default:
2152 if (((c >= ' ' && c <= '~') ||
2153 ((unsigned char)c >= 160)) && pos < 40) {
2154 username[pos++] = c;
2155 c_write(&c, 1);
2156 }
2157 break;
2158 }
2159 }
2160 c_write("\r\n", 2);
2161 username[strcspn(username, "\n\r")] = '\0';
2162 } else {
2163 char stuff[200];
2164 strncpy(username, cfg.username, 99);
2165 username[99] = '\0';
67779be7 2166 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
7cca0d81 2167 sprintf(stuff, "Using username \"%s\".\r\n", username);
2168 c_write(stuff, strlen(stuff));
2169 }
2170 }
2171
67779be7 2172 if (!(flags & FLAG_INTERACTIVE)) {
7cca0d81 2173 char prompt[200];
2174 sprintf(prompt, "%s@%s's password: ", cfg.username, savedhost);
2175 if (!ssh_get_password(prompt, password, sizeof(password))) {
2176 /*
2177 * get_password failed to get a password (for
2178 * example because one was supplied on the command
2179 * line which has already failed to work).
2180 * Terminate.
2181 */
2182 logevent("No more passwords to try");
2183 ssh_state = SSH_STATE_CLOSED;
2184 crReturnV;
2185 }
2186 } else {
2187 c_write("password: ", 10);
67779be7 2188 ssh_send_ok = 1;
7cca0d81 2189
2190 pos = 0;
2191 while (pos >= 0) {
2192 crWaitUntilV(!ispkt);
2193 while (inlen--) switch (c = *in++) {
2194 case 10: case 13:
2195 password[pos] = 0;
2196 pos = -1;
2197 break;
2198 case 8: case 127:
2199 if (pos > 0)
2200 pos--;
2201 break;
2202 case 21: case 27:
2203 pos = 0;
2204 break;
2205 case 3: case 4:
2206 random_save_seed();
2207 exit(0);
2208 break;
2209 default:
2210 if (((c >= ' ' && c <= '~') ||
2211 ((unsigned char)c >= 160)) && pos < 40)
2212 password[pos++] = c;
2213 break;
2214 }
2215 }
2216 c_write("\r\n", 2);
2217 }
2218
2219 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
2220 ssh2_pkt_addstring(username);
2221 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2222 ssh2_pkt_addstring("password");
2223 ssh2_pkt_addbool(FALSE);
2224 ssh2_pkt_addstring(password);
2225 ssh2_pkt_send();
2226
2227 crWaitUntilV(ispkt);
2228 if (pktin.type != SSH2_MSG_USERAUTH_SUCCESS) {
2229 c_write("Access denied\r\n", 15);
2230 logevent("Authentication refused");
2231 } else
2232 break;
2233 }
2234
2235 /*
2236 * Now we're authenticated for the connection protocol. The
2237 * connection protocol will automatically have started at this
2238 * point; there's no need to send SERVICE_REQUEST.
2239 */
2240
2241 /*
2242 * So now create a channel with a session in it.
2243 */
d211621f 2244 mainchan = malloc(sizeof(struct ssh_channel));
2245 mainchan->localid = 100; /* as good as any */
7cca0d81 2246 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
2247 ssh2_pkt_addstring("session");
d211621f 2248 ssh2_pkt_adduint32(mainchan->localid);
2249 ssh2_pkt_adduint32(0x7FFFFFFFUL); /* our window size */
2250 ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
7cca0d81 2251 ssh2_pkt_send();
2252 crWaitUntilV(ispkt);
2253 if (pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
8d5de777 2254 bombout(("Server refused to open a session"));
2255 crReturnV;
7cca0d81 2256 /* FIXME: error data comes back in FAILURE packet */
2257 }
d211621f 2258 if (ssh2_pkt_getuint32() != mainchan->localid) {
8d5de777 2259 bombout(("Server's channel confirmation cited wrong channel"));
2260 crReturnV;
7cca0d81 2261 }
d211621f 2262 mainchan->remoteid = ssh2_pkt_getuint32();
2263 mainchan->u.v2.remwindow = ssh2_pkt_getuint32();
2264 mainchan->u.v2.remmaxpkt = ssh2_pkt_getuint32();
2265 mainchan->u.v2.outbuffer = NULL;
2266 mainchan->u.v2.outbuflen = mainchan->u.v2.outbufsize = 0;
7cca0d81 2267 logevent("Opened channel for session");
2268
2269 /*
2270 * Now allocate a pty for the session.
2271 */
67779be7 2272 if (!cfg.nopty) {
2273 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
2274 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
2275 ssh2_pkt_addstring("pty-req");
2276 ssh2_pkt_addbool(1); /* want reply */
2277 ssh2_pkt_addstring(cfg.termtype);
2278 ssh2_pkt_adduint32(cols);
2279 ssh2_pkt_adduint32(rows);
2280 ssh2_pkt_adduint32(0); /* pixel width */
2281 ssh2_pkt_adduint32(0); /* pixel height */
2282 ssh2_pkt_addstring_start();
2283 ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
2284 ssh2_pkt_send();
7cca0d81 2285
67779be7 2286 do {
2287 crWaitUntilV(ispkt);
2288 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2289 /* FIXME: be able to handle other channels here */
2290 if (ssh2_pkt_getuint32() != mainchan->localid)
2291 continue; /* wrong channel */
2292 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2293 }
2294 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
7cca0d81 2295
67779be7 2296 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
2297 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
8d5de777 2298 bombout(("Server got confused by pty request"));
2299 crReturnV;
67779be7 2300 }
2301 c_write("Server refused to allocate pty\r\n", 32);
2302 } else {
2303 logevent("Allocated pty");
7cca0d81 2304 }
7cca0d81 2305 }
2306
2307 /*
67779be7 2308 * Start a shell or a remote command.
7cca0d81 2309 */
2310 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
d211621f 2311 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
67779be7 2312 if (*cfg.remote_cmd) {
2313 ssh2_pkt_addstring("exec");
2314 ssh2_pkt_addbool(1); /* want reply */
2315 ssh2_pkt_addstring(cfg.remote_cmd);
2316 } else {
2317 ssh2_pkt_addstring("shell");
2318 ssh2_pkt_addbool(1); /* want reply */
2319 }
7cca0d81 2320 ssh2_pkt_send();
d211621f 2321 do {
7cca0d81 2322 crWaitUntilV(ispkt);
d211621f 2323 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2324 /* FIXME: be able to handle other channels here */
2325 if (ssh2_pkt_getuint32() != mainchan->localid)
2326 continue; /* wrong channel */
2327 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2328 }
7cca0d81 2329 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2330 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
2331 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
8d5de777 2332 bombout(("Server got confused by shell/command request"));
2333 crReturnV;
7cca0d81 2334 }
8d5de777 2335 bombout(("Server refused to start a shell/command"));
2336 crReturnV;
7cca0d81 2337 } else {
8d5de777 2338 logevent("Started a shell/command");
7cca0d81 2339 }
2340
2341 /*
2342 * Transfer data!
2343 */
8ccc75b0 2344 ssh_send_ok = 1;
6f34e365 2345 begin_session();
7cca0d81 2346 while (1) {
d211621f 2347 static int try_send;
e5574168 2348 crReturnV;
d211621f 2349 try_send = FALSE;
7cca0d81 2350 if (ispkt) {
2351 if (pktin.type == SSH2_MSG_CHANNEL_DATA ||
2352 pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
2353 char *data;
2354 int length;
d211621f 2355 /* FIXME: be able to handle other channels here */
2356 if (ssh2_pkt_getuint32() != mainchan->localid)
7cca0d81 2357 continue; /* wrong channel */
2358 if (pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
2359 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR)
2360 continue; /* extended but not stderr */
2361 ssh2_pkt_getstring(&data, &length);
d211621f 2362 if (data) {
7cca0d81 2363 c_write(data, length);
d211621f 2364 /*
2365 * Enlarge the window again at the remote side,
2366 * just in case it ever runs down and they fail
2367 * to send us any more data.
2368 */
2369 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2370 ssh2_pkt_adduint32(mainchan->remoteid);
2371 ssh2_pkt_adduint32(length);
2372 ssh2_pkt_send();
2373 }
7cca0d81 2374 } else if (pktin.type == SSH2_MSG_DISCONNECT) {
2375 ssh_state = SSH_STATE_CLOSED;
d211621f 2376 logevent("Received disconnect message");
7cca0d81 2377 } else if (pktin.type == SSH2_MSG_CHANNEL_REQUEST) {
2378 continue; /* exit status et al; ignore (FIXME?) */
d211621f 2379 } else if (pktin.type == SSH2_MSG_CHANNEL_EOF) {
2380 continue; /* remote sends EOF; ignore */
2381 } else if (pktin.type == SSH2_MSG_CHANNEL_CLOSE) {
2382 /* FIXME: be able to handle other channels here */
2383 if (ssh2_pkt_getuint32() != mainchan->localid)
2384 continue; /* wrong channel */
2385 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
2386 ssh2_pkt_adduint32(mainchan->remoteid);
2387 ssh2_pkt_send();
2388 /* FIXME: mark the channel as closed */
2389 if (1 /* FIXME: "all channels are closed" */) {
2390 logevent("All channels closed. Disconnecting");
2391 ssh2_pkt_init(SSH2_MSG_DISCONNECT);
2392 ssh2_pkt_send();
2393 }
2394 continue; /* remote sends close; ignore (FIXME) */
7cca0d81 2395 } else if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
d211621f 2396 /* FIXME: be able to handle other channels here */
2397 if (ssh2_pkt_getuint32() != mainchan->localid)
2398 continue; /* wrong channel */
2399 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2400 try_send = TRUE;
7cca0d81 2401 } else {
8d5de777 2402 bombout(("Strange packet received: type %d", pktin.type));
2403 crReturnV;
7cca0d81 2404 }
2405 } else {
d211621f 2406 /*
2407 * We have spare data. Add it to the channel buffer.
2408 */
2409 if (mainchan->u.v2.outbufsize <
2410 mainchan->u.v2.outbuflen + inlen) {
2411 mainchan->u.v2.outbufsize =
2412 mainchan->u.v2.outbuflen + inlen + 1024;
2413 mainchan->u.v2.outbuffer = srealloc(mainchan->u.v2.outbuffer,
2414 mainchan->u.v2.outbufsize);
2415 }
2416 memcpy(mainchan->u.v2.outbuffer + mainchan->u.v2.outbuflen,
2417 in, inlen);
2418 mainchan->u.v2.outbuflen += inlen;
2419 try_send = TRUE;
7cca0d81 2420 }
d211621f 2421 if (try_send) {
2422 /*
2423 * Try to send data on the channel if we can. (FIXME:
2424 * on _all_ channels.)
2425 */
2426 while (mainchan->u.v2.remwindow > 0 &&
2427 mainchan->u.v2.outbuflen > 0) {
2428 unsigned len = mainchan->u.v2.remwindow;
2429 if (len > mainchan->u.v2.outbuflen)
2430 len = mainchan->u.v2.outbuflen;
2431 if (len > mainchan->u.v2.remmaxpkt)
2432 len = mainchan->u.v2.remmaxpkt;
2433 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
2434 ssh2_pkt_adduint32(mainchan->remoteid);
2435 ssh2_pkt_addstring_start();
2436 ssh2_pkt_addstring_data(mainchan->u.v2.outbuffer, len);
2437 ssh2_pkt_send();
2438 mainchan->u.v2.outbuflen -= len;
2439 memmove(mainchan->u.v2.outbuffer, mainchan->u.v2.outbuffer+len,
2440 mainchan->u.v2.outbuflen);
2441 mainchan->u.v2.remwindow -= len;
2442 }
2443 }
e5574168 2444 }
2445
2446 crFinishV;
2447}
2448
2449/*
7cca0d81 2450 * Handle the top-level SSH2 protocol.
2451 */
2452static void ssh2_protocol(unsigned char *in, int inlen, int ispkt)
2453{
2454 if (do_ssh2_transport(in, inlen, ispkt) == 0)
2455 return;
2456 do_ssh2_authconn(in, inlen, ispkt);
2457}
2458
2459/*
374330e2 2460 * Called to set up the connection. Will arrange for WM_NETEVENT
2461 * messages to be passed to the specified window, whose window
2462 * procedure should then call telnet_msg().
2463 *
2464 * Returns an error message, or NULL on success.
374330e2 2465 */
2466static char *ssh_init (HWND hwnd, char *host, int port, char **realhost) {
fb09bf1c 2467 char *p;
8f203108 2468
2469#ifdef MSCRYPTOAPI
2470 if(crypto_startup() == 0)
2471 return "Microsoft high encryption pack not installed!";
2472#endif
374330e2 2473
fb09bf1c 2474 p = connect_to_host(host, port, realhost);
2475 if (p != NULL)
2476 return p;
374330e2 2477
2478 if (!do_ssh_init())
2479 return "Protocol initialisation error";
2480
4017be6d 2481 if (hwnd && WSAAsyncSelect (s, hwnd, WM_NETEVENT, FD_READ | FD_CLOSE) == SOCKET_ERROR)
374330e2 2482 switch (WSAGetLastError()) {
2483 case WSAENETDOWN: return "Network is down";
2484 default: return "WSAAsyncSelect(): unknown error";
2485 }
2486
2487 return NULL;
2488}
2489
2490/*
2491 * Process a WM_NETEVENT message. Will return 0 if the connection
2492 * has closed, or <0 for a socket error.
2493 */
2494static int ssh_msg (WPARAM wParam, LPARAM lParam) {
2495 int ret;
2496 char buf[256];
2497
8ce72d2c 2498 /*
2499 * Because reading less than the whole of the available pending
2500 * data can generate an FD_READ event, we need to allow for the
2501 * possibility that FD_READ may arrive with FD_CLOSE already in
2502 * the queue; so it's possible that we can get here even with s
2503 * invalid. If so, we return 1 and don't worry about it.
2504 */
2505 if (s == INVALID_SOCKET)
2506 return 1;
374330e2 2507
8d5de777 2508 if (WSAGETSELECTERROR(lParam) != 0) {
2509 closesocket(s);
2510 s = INVALID_SOCKET;
374330e2 2511 return -WSAGETSELECTERROR(lParam);
8d5de777 2512 }
374330e2 2513
2514 switch (WSAGETSELECTEVENT(lParam)) {
2515 case FD_READ:
8ce72d2c 2516 case FD_CLOSE:
374330e2 2517 ret = recv(s, buf, sizeof(buf), 0);
2518 if (ret < 0 && WSAGetLastError() == WSAEWOULDBLOCK)
2519 return 1;
8d5de777 2520 if (ret < 0) { /* any _other_ error */
2521 closesocket(s);
2522 s = INVALID_SOCKET;
374330e2 2523 return -10000-WSAGetLastError();
8d5de777 2524 }
374330e2 2525 if (ret == 0) {
2526 s = INVALID_SOCKET;
8ce72d2c 2527 return 0;
374330e2 2528 }
2529 ssh_gotdata (buf, ret);
85ee8208 2530 if (ssh_state == SSH_STATE_CLOSED) {
2531 closesocket(s);
2532 s = INVALID_SOCKET;
2533 return 0;
2534 }
374330e2 2535 return 1;
374330e2 2536 }
2537 return 1; /* shouldn't happen, but WTF */
2538}
2539
2540/*
2541 * Called to send data down the Telnet connection.
2542 */
2543static void ssh_send (char *buf, int len) {
2544 if (s == INVALID_SOCKET)
2545 return;
2546
2547 ssh_protocol(buf, len, 0);
2548}
2549
2550/*
2551 * Called to set the size of the window from Telnet's POV.
2552 */
2553static void ssh_size(void) {
2554 switch (ssh_state) {
2555 case SSH_STATE_BEFORE_SIZE:
21248260 2556 case SSH_STATE_CLOSED:
374330e2 2557 break; /* do nothing */
2558 case SSH_STATE_INTERMED:
2559 size_needed = TRUE; /* buffer for later */
2560 break;
2561 case SSH_STATE_SESSION:
fef97f43 2562 if (!cfg.nopty) {
e5574168 2563 send_packet(SSH1_CMSG_WINDOW_SIZE,
fb09bf1c 2564 PKT_INT, rows, PKT_INT, cols,
2565 PKT_INT, 0, PKT_INT, 0, PKT_END);
fef97f43 2566 }
374330e2 2567 }
2568}
2569
2570/*
6abbf9e3 2571 * Send Telnet special codes. TS_EOF is useful for `plink', so you
2572 * can send an EOF and collect resulting output (e.g. `plink
2573 * hostname sort').
374330e2 2574 */
2575static void ssh_special (Telnet_Special code) {
6abbf9e3 2576 if (code == TS_EOF) {
67779be7 2577 if (ssh_version == 1) {
6abbf9e3 2578 send_packet(SSH1_CMSG_EOF, PKT_END);
2579 } else {
2580 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
d211621f 2581 ssh2_pkt_adduint32(mainchan->remoteid);
6abbf9e3 2582 ssh2_pkt_send();
2583 }
67779be7 2584 logevent("Sent EOF message");
6abbf9e3 2585 } else {
2586 /* do nothing */
2587 }
374330e2 2588}
2589
fb09bf1c 2590
2591/*
2592 * Read and decrypt one incoming SSH packet.
2593 * (only used by pSCP)
2594 */
2595static void get_packet(void)
2596{
2597 unsigned char buf[4096], *p;
2598 long to_read;
2599 int len;
2600
fb09bf1c 2601 p = NULL;
2602 len = 0;
2603
2604 while ((to_read = s_rdpkt(&p, &len)) > 0) {
2605 if (to_read > sizeof(buf)) to_read = sizeof(buf);
2606 len = s_read(buf, to_read);
2607 if (len != to_read) {
2608 closesocket(s);
2609 s = INVALID_SOCKET;
2610 return;
2611 }
2612 p = buf;
2613 }
2614
2615 assert(len == 0);
2616}
2617
2618/*
2619 * Receive a block of data over the SSH link. Block until
2620 * all data is available. Return nr of bytes read (0 if lost connection).
2621 * (only used by pSCP)
2622 */
2623int ssh_scp_recv(unsigned char *buf, int len)
2624{
2625 static int pending_input_len = 0;
2626 static unsigned char *pending_input_ptr;
2627 int to_read = len;
2628
fb09bf1c 2629 if (pending_input_len >= to_read) {
2630 memcpy(buf, pending_input_ptr, to_read);
2631 pending_input_ptr += to_read;
2632 pending_input_len -= to_read;
2633 return len;
2634 }
2635
2636 if (pending_input_len > 0) {
2637 memcpy(buf, pending_input_ptr, pending_input_len);
2638 buf += pending_input_len;
2639 to_read -= pending_input_len;
2640 pending_input_len = 0;
2641 }
2642
2643 if (s == INVALID_SOCKET)
2644 return 0;
2645 while (to_read > 0) {
2646 get_packet();
2647 if (s == INVALID_SOCKET)
2648 return 0;
e5574168 2649 if (pktin.type == SSH1_SMSG_STDOUT_DATA) {
fb09bf1c 2650 int plen = GET_32BIT(pktin.body);
2651 if (plen <= to_read) {
2652 memcpy(buf, pktin.body + 4, plen);
2653 buf += plen;
2654 to_read -= plen;
2655 } else {
2656 memcpy(buf, pktin.body + 4, to_read);
2657 pending_input_len = plen - to_read;
2658 pending_input_ptr = pktin.body + 4 + to_read;
2659 to_read = 0;
2660 }
e5574168 2661 } else if (pktin.type == SSH1_SMSG_STDERR_DATA) {
fb09bf1c 2662 int plen = GET_32BIT(pktin.body);
2663 fwrite(pktin.body + 4, plen, 1, stderr);
e5574168 2664 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
fb09bf1c 2665 logevent("Received disconnect request");
e5574168 2666 } else if (pktin.type == SSH1_SMSG_SUCCESS ||
2667 pktin.type == SSH1_SMSG_FAILURE) {
fb09bf1c 2668 /* ignore */
e5574168 2669 } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) {
fb09bf1c 2670 char logbuf[100];
2671 sprintf(logbuf, "Remote exit status: %d", GET_32BIT(pktin.body));
2672 logevent(logbuf);
e5574168 2673 send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
fb09bf1c 2674 logevent("Closing connection");
2675 closesocket(s);
2676 s = INVALID_SOCKET;
2677 } else {
8d5de777 2678 bombout(("Strange packet received: type %d", pktin.type));
2679 return 0;
fb09bf1c 2680 }
2681 }
2682
2683 return len;
2684}
2685
2686/*
2687 * Send a block of data over the SSH link.
2688 * Block until all data is sent.
2689 * (only used by pSCP)
2690 */
2691void ssh_scp_send(unsigned char *buf, int len)
2692{
fb09bf1c 2693 if (s == INVALID_SOCKET)
2694 return;
e5574168 2695 send_packet(SSH1_CMSG_STDIN_DATA,
fb09bf1c 2696 PKT_INT, len, PKT_DATA, buf, len, PKT_END);
2697}
2698
2699/*
2700 * Send an EOF notification to the server.
2701 * (only used by pSCP)
2702 */
2703void ssh_scp_send_eof(void)
2704{
fb09bf1c 2705 if (s == INVALID_SOCKET)
2706 return;
e5574168 2707 send_packet(SSH1_CMSG_EOF, PKT_END);
fb09bf1c 2708}
2709
2710/*
2711 * Set up the connection, login on the remote host and
2712 * start execution of a command.
2713 * Returns an error message, or NULL on success.
2714 * (only used by pSCP)
2715 */
2716char *ssh_scp_init(char *host, int port, char *cmd, char **realhost)
2717{
2718 char buf[160], *p;
2719
fb09bf1c 2720#ifdef MSCRYPTOAPI
2721 if (crypto_startup() == 0)
2722 return "Microsoft high encryption pack not installed!";
2723#endif
2724
2725 p = connect_to_host(host, port, realhost);
2726 if (p != NULL)
2727 return p;
2728
2729 random_init();
2730
2731 if (!do_ssh_init())
2732 return "Protocol initialisation error";
2733
2734 /* Exchange keys and login */
2735 do {
2736 get_packet();
2737 if (s == INVALID_SOCKET)
2738 return "Connection closed by remote host";
e5574168 2739 } while (!do_ssh1_login(NULL, 0, 1));
85ee8208 2740
2741 if (ssh_state == SSH_STATE_CLOSED) {
2742 closesocket(s);
2743 s = INVALID_SOCKET;
2744 return "Session initialisation error";
2745 }
fb09bf1c 2746
2747 /* Execute command */
2748 sprintf(buf, "Sending command: %.100s", cmd);
2749 logevent(buf);
e5574168 2750 send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
fb09bf1c 2751
2752 return NULL;
2753}
2754
8ccc75b0 2755static SOCKET ssh_socket(void) { return s; }
2756
2757static int ssh_sendok(void) { return ssh_send_ok; }
fb09bf1c 2758
374330e2 2759Backend ssh_backend = {
2760 ssh_init,
2761 ssh_msg,
2762 ssh_send,
2763 ssh_size,
4017be6d 2764 ssh_special,
8ccc75b0 2765 ssh_socket,
2766 ssh_sendok
374330e2 2767};
Local modifications for Simon Tatham's `PuTTY' SSH client and terminal emulator