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 extern const struct ssh_signkey ssh_rsa;
201 const static struct ssh_signkey *hostkey_algs[] = { &ssh_rsa, &ssh_dss };
203 extern const struct ssh_mac ssh_md5, ssh_sha1, ssh_sha1_buggy;
205 static void nullmac_key(unsigned char *key) { }
206 static void nullmac_generate(unsigned char *blk, int len, unsigned long seq) { }
207 static int nullmac_verify(unsigned char *blk, int len, unsigned long seq) { return 1; }
208 const static struct ssh_mac ssh_mac_none = {
209 nullmac_key, nullmac_key, nullmac_generate, nullmac_verify, "none", 0
211 const static struct ssh_mac *macs[] = {
212 &ssh_sha1, &ssh_md5, &ssh_mac_none };
213 const static struct ssh_mac *buggymacs[] = {
214 &ssh_sha1_buggy, &ssh_md5, &ssh_mac_none };
216 static void ssh_comp_none_init(void) { }
217 static int ssh_comp_none_block(unsigned char *block, int len,
218 unsigned char **outblock, int *outlen) {
221 const static struct ssh_compress ssh_comp_none = {
223 ssh_comp_none_init, ssh_comp_none_block,
224 ssh_comp_none_init, ssh_comp_none_block
226 extern const struct ssh_compress ssh_zlib;
227 const static struct ssh_compress *compressions[] = {
228 &ssh_zlib, &ssh_comp_none };
230 enum { /* channel types */
237 * 2-3-4 tree storing channels.
240 unsigned remoteid, localid;
243 struct ssh2_data_channel {
244 unsigned char *outbuffer;
245 unsigned outbuflen, outbufsize;
246 unsigned remwindow, remmaxpkt;
249 struct ssh_agent_channel {
250 unsigned char *message;
251 unsigned char msglen[4];
252 int lensofar, totallen;
254 struct ssh_x11_channel {
269 static SHA_State exhash, exhashbase;
271 static Socket s = NULL;
273 static unsigned char session_key[32];
274 static int ssh1_compressing;
275 static int ssh_agentfwd_enabled;
276 static int ssh_X11_fwd_enabled;
277 static const struct ssh_cipher *cipher = NULL;
278 static const struct ssh2_cipher *cscipher = NULL;
279 static const struct ssh2_cipher *sccipher = NULL;
280 static const struct ssh_mac *csmac = NULL;
281 static const struct ssh_mac *scmac = NULL;
282 static const struct ssh_compress *cscomp = NULL;
283 static const struct ssh_compress *sccomp = NULL;
284 static const struct ssh_kex *kex = NULL;
285 static const struct ssh_signkey *hostkey = NULL;
286 int (*ssh_get_password)(const char *prompt, char *str, int maxlen) = NULL;
288 static char *savedhost;
289 static int savedport;
290 static int ssh_send_ok;
291 static int ssh_echoing, ssh_editing;
293 static tree234 *ssh_channels; /* indexed by local id */
294 static struct ssh_channel *mainchan; /* primary session channel */
298 SSH_STATE_BEFORE_SIZE,
302 } ssh_state = SSH_STATE_PREPACKET;
304 static int size_needed = FALSE, eof_needed = FALSE;
306 static struct Packet pktin = { 0, 0, NULL, NULL, 0 };
307 static struct Packet pktout = { 0, 0, NULL, NULL, 0 };
308 static unsigned char *deferred_send_data = NULL;
309 static int deferred_len = 0, deferred_size = 0;
311 static int ssh_version;
312 static void (*ssh_protocol)(unsigned char *in, int inlen, int ispkt);
313 static void ssh1_protocol(unsigned char *in, int inlen, int ispkt);
314 static void ssh2_protocol(unsigned char *in, int inlen, int ispkt);
315 static void ssh_size(void);
316 static void ssh_special (Telnet_Special);
317 static void ssh2_try_send(struct ssh_channel *c);
318 static void ssh2_add_channel_data(struct ssh_channel *c, char *buf, int len);
320 static int (*s_rdpkt)(unsigned char **data, int *datalen);
322 static struct rdpkt1_state_tag {
323 long len, pad, biglen, to_read;
324 unsigned long realcrc, gotcrc;
330 static struct rdpkt2_state_tag {
331 long len, pad, payload, packetlen, maclen;
334 unsigned long incoming_sequence;
337 static int ssh_channelcmp(void *av, void *bv) {
338 struct ssh_channel *a = (struct ssh_channel *)av;
339 struct ssh_channel *b = (struct ssh_channel *)bv;
340 if (a->localid < b->localid) return -1;
341 if (a->localid > b->localid) return +1;
344 static int ssh_channelfind(void *av, void *bv) {
345 unsigned *a = (unsigned *)av;
346 struct ssh_channel *b = (struct ssh_channel *)bv;
347 if (*a < b->localid) return -1;
348 if (*a > b->localid) return +1;
352 static void c_write (char *buf, int len) {
353 if ((flags & FLAG_STDERR)) {
355 for (i = 0; i < len; i++)
357 fputc(buf[i], stderr);
360 from_backend(1, buf, len);
364 * Collect incoming data in the incoming packet buffer.
365 * Decipher and verify the packet when it is completely read.
366 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
367 * Update the *data and *datalen variables.
368 * Return the additional nr of bytes needed, or 0 when
369 * a complete packet is available.
371 static int ssh1_rdpkt(unsigned char **data, int *datalen)
373 struct rdpkt1_state_tag *st = &rdpkt1_state;
382 for (st->i = st->len = 0; st->i < 4; st->i++) {
383 while ((*datalen) == 0)
385 st->len = (st->len << 8) + **data;
386 (*data)++, (*datalen)--;
390 if (st->len == 0x52656d6f) { /* "Remo"te server has closed ... */
391 st->len = 0x300; /* big enough to carry to end */
395 st->pad = 8 - (st->len % 8);
396 st->biglen = st->len + st->pad;
397 pktin.length = st->len - 5;
399 if (pktin.maxlen < st->biglen) {
400 pktin.maxlen = st->biglen;
401 pktin.data = (pktin.data == NULL ? smalloc(st->biglen+APIEXTRA) :
402 srealloc(pktin.data, st->biglen+APIEXTRA));
404 fatalbox("Out of memory");
407 st->to_read = st->biglen;
409 while (st->to_read > 0) {
410 st->chunk = st->to_read;
411 while ((*datalen) == 0)
412 crReturn(st->to_read);
413 if (st->chunk > (*datalen))
414 st->chunk = (*datalen);
415 memcpy(st->p, *data, st->chunk);
417 *datalen -= st->chunk;
419 st->to_read -= st->chunk;
423 cipher->decrypt(pktin.data, st->biglen);
425 debug(("Got packet len=%d pad=%d\r\n", st->len, st->pad));
426 for (st->i = 0; st->i < st->biglen; st->i++)
427 debug((" %02x", (unsigned char)pktin.data[st->i]));
431 st->realcrc = crc32(pktin.data, st->biglen-4);
432 st->gotcrc = GET_32BIT(pktin.data+st->biglen-4);
433 if (st->gotcrc != st->realcrc) {
434 bombout(("Incorrect CRC received on packet"));
438 pktin.body = pktin.data + st->pad + 1;
440 if (ssh1_compressing) {
441 unsigned char *decompblk;
445 debug(("Packet payload pre-decompression:\n"));
446 for (i = -1; i < pktin.length; i++)
447 debug((" %02x", (unsigned char)pktin.body[i]));
450 zlib_decompress_block(pktin.body-1, pktin.length+1,
451 &decompblk, &decomplen);
453 if (pktin.maxlen < st->pad + decomplen) {
454 pktin.maxlen = st->pad + decomplen;
455 pktin.data = srealloc(pktin.data, pktin.maxlen+APIEXTRA);
456 pktin.body = pktin.data + st->pad + 1;
458 fatalbox("Out of memory");
461 memcpy(pktin.body-1, decompblk, decomplen);
463 pktin.length = decomplen-1;
465 debug(("Packet payload post-decompression:\n"));
466 for (i = -1; i < pktin.length; i++)
467 debug((" %02x", (unsigned char)pktin.body[i]));
472 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
473 pktin.type == SSH1_SMSG_STDERR_DATA ||
474 pktin.type == SSH1_MSG_DEBUG ||
475 pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE ||
476 pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
477 long strlen = GET_32BIT(pktin.body);
478 if (strlen + 4 != pktin.length) {
479 bombout(("Received data packet with bogus string length"));
484 pktin.type = pktin.body[-1];
486 if (pktin.type == SSH1_MSG_DEBUG) {
487 /* log debug message */
489 int strlen = GET_32BIT(pktin.body);
490 strcpy(buf, "Remote: ");
491 if (strlen > 70) strlen = 70;
492 memcpy(buf+8, pktin.body+4, strlen);
493 buf[8+strlen] = '\0';
496 } else if (pktin.type == SSH1_MSG_IGNORE) {
504 static int ssh2_rdpkt(unsigned char **data, int *datalen)
506 struct rdpkt2_state_tag *st = &rdpkt2_state;
514 st->cipherblk = sccipher->blksize;
517 if (st->cipherblk < 8)
520 if (pktin.maxlen < st->cipherblk) {
521 pktin.maxlen = st->cipherblk;
522 pktin.data = (pktin.data == NULL ? smalloc(st->cipherblk+APIEXTRA) :
523 srealloc(pktin.data, st->cipherblk+APIEXTRA));
525 fatalbox("Out of memory");
529 * Acquire and decrypt the first block of the packet. This will
530 * contain the length and padding details.
532 for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
533 while ((*datalen) == 0)
534 crReturn(st->cipherblk-st->i);
535 pktin.data[st->i] = *(*data)++;
539 if (!memcmp(pktin.data, "Remo", 4)) {/* "Remo"te server has closed ... */
544 sccipher->decrypt(pktin.data, st->cipherblk);
547 * Now get the length and padding figures.
549 st->len = GET_32BIT(pktin.data);
550 st->pad = pktin.data[4];
553 * This enables us to deduce the payload length.
555 st->payload = st->len - st->pad - 1;
557 pktin.length = st->payload + 5;
560 * So now we can work out the total packet length.
562 st->packetlen = st->len + 4;
563 st->maclen = scmac ? scmac->len : 0;
566 * Adjust memory allocation if packet is too big.
568 if (pktin.maxlen < st->packetlen+st->maclen) {
569 pktin.maxlen = st->packetlen+st->maclen;
570 pktin.data = (pktin.data == NULL ? smalloc(pktin.maxlen+APIEXTRA) :
571 srealloc(pktin.data, pktin.maxlen+APIEXTRA));
573 fatalbox("Out of memory");
577 * Read and decrypt the remainder of the packet.
579 for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen; st->i++) {
580 while ((*datalen) == 0)
581 crReturn(st->packetlen + st->maclen - st->i);
582 pktin.data[st->i] = *(*data)++;
585 /* Decrypt everything _except_ the MAC. */
587 sccipher->decrypt(pktin.data + st->cipherblk,
588 st->packetlen - st->cipherblk);
591 debug(("Got packet len=%d pad=%d\r\n", st->len, st->pad));
592 for (st->i = 0; st->i < st->packetlen; st->i++)
593 debug((" %02x", (unsigned char)pktin.data[st->i]));
600 if (scmac && !scmac->verify(pktin.data, st->len+4, st->incoming_sequence)) {
601 bombout(("Incorrect MAC received on packet"));
604 st->incoming_sequence++; /* whether or not we MACed */
607 * Decompress packet payload.
610 unsigned char *newpayload;
612 if (sccomp && sccomp->decompress(pktin.data+5, pktin.length-5,
613 &newpayload, &newlen)) {
614 if (pktin.maxlen < newlen+5) {
615 pktin.maxlen = newlen+5;
616 pktin.data = (pktin.data == NULL ? smalloc(pktin.maxlen+APIEXTRA) :
617 srealloc(pktin.data, pktin.maxlen+APIEXTRA));
619 fatalbox("Out of memory");
621 pktin.length = 5 + newlen;
622 memcpy(pktin.data+5, newpayload, newlen);
624 debug(("Post-decompression payload:\r\n"));
625 for (st->i = 0; st->i < newlen; st->i++)
626 debug((" %02x", (unsigned char)pktin.data[5+st->i]));
635 pktin.type = pktin.data[5];
637 if (pktin.type == SSH2_MSG_IGNORE || pktin.type == SSH2_MSG_DEBUG)
638 goto next_packet; /* FIXME: print DEBUG message */
643 static void ssh1_pktout_size(int len) {
646 len += 5; /* type and CRC */
650 pktout.length = len-5;
651 if (pktout.maxlen < biglen) {
652 pktout.maxlen = biglen;
654 /* Allocate enough buffer space for extra block
655 * for MS CryptEncrypt() */
656 pktout.data = (pktout.data == NULL ? smalloc(biglen+12) :
657 srealloc(pktout.data, biglen+12));
659 pktout.data = (pktout.data == NULL ? smalloc(biglen+4) :
660 srealloc(pktout.data, biglen+4));
663 fatalbox("Out of memory");
665 pktout.body = pktout.data+4+pad+1;
668 static void s_wrpkt_start(int type, int len) {
669 ssh1_pktout_size(len);
673 static void s_wrpkt(void) {
674 int pad, len, biglen, i;
677 pktout.body[-1] = pktout.type;
679 if (ssh1_compressing) {
680 unsigned char *compblk;
683 debug(("Packet payload pre-compression:\n"));
684 for (i = -1; i < pktout.length; i++)
685 debug((" %02x", (unsigned char)pktout.body[i]));
688 zlib_compress_block(pktout.body-1, pktout.length+1,
690 ssh1_pktout_size(complen-1);
691 memcpy(pktout.body-1, compblk, complen);
694 debug(("Packet payload post-compression:\n"));
695 for (i = -1; i < pktout.length; i++)
696 debug((" %02x", (unsigned char)pktout.body[i]));
701 len = pktout.length + 5; /* type and CRC */
705 for (i=0; i<pad; i++)
706 pktout.data[i+4] = random_byte();
707 crc = crc32(pktout.data+4, biglen-4);
708 PUT_32BIT(pktout.data+biglen, crc);
709 PUT_32BIT(pktout.data, len);
712 debug(("Sending packet len=%d\r\n", biglen+4));
713 for (i = 0; i < biglen+4; i++)
714 debug((" %02x", (unsigned char)pktout.data[i]));
718 cipher->encrypt(pktout.data+4, biglen);
720 sk_write(s, pktout.data, biglen+4);
724 * Construct a packet with the specified contents and
725 * send it to the server.
727 static void send_packet(int pkttype, ...)
730 unsigned char *p, *argp, argchar;
731 unsigned long argint;
732 int pktlen, argtype, arglen;
736 va_start(args, pkttype);
737 while ((argtype = va_arg(args, int)) != PKT_END) {
740 (void) va_arg(args, int);
744 (void) va_arg(args, char);
748 (void) va_arg(args, unsigned char *);
749 arglen = va_arg(args, int);
753 argp = va_arg(args, unsigned char *);
754 arglen = strlen(argp);
755 pktlen += 4 + arglen;
758 bn = va_arg(args, Bignum);
759 pktlen += ssh1_bignum_length(bn);
767 s_wrpkt_start(pkttype, pktlen);
770 va_start(args, pkttype);
771 while ((argtype = va_arg(args, int)) != PKT_END) {
774 argint = va_arg(args, int);
775 PUT_32BIT(p, argint);
779 argchar = va_arg(args, unsigned char);
784 argp = va_arg(args, unsigned char *);
785 arglen = va_arg(args, int);
786 memcpy(p, argp, arglen);
790 argp = va_arg(args, unsigned char *);
791 arglen = strlen(argp);
792 PUT_32BIT(p, arglen);
793 memcpy(p + 4, argp, arglen);
797 bn = va_arg(args, Bignum);
798 p += ssh1_write_bignum(p, bn);
807 static int ssh_versioncmp(char *a, char *b) {
809 unsigned long av, bv;
811 av = strtoul(a, &ae, 10);
812 bv = strtoul(b, &be, 10);
813 if (av != bv) return (av < bv ? -1 : +1);
814 if (*ae == '.') ae++;
815 if (*be == '.') be++;
816 av = strtoul(ae, &ae, 10);
817 bv = strtoul(be, &be, 10);
818 if (av != bv) return (av < bv ? -1 : +1);
824 * Utility routines for putting an SSH-protocol `string' and
825 * `uint32' into a SHA state.
828 static void sha_string(SHA_State *s, void *str, int len) {
829 unsigned char lenblk[4];
830 PUT_32BIT(lenblk, len);
831 SHA_Bytes(s, lenblk, 4);
832 SHA_Bytes(s, str, len);
835 static void sha_uint32(SHA_State *s, unsigned i) {
836 unsigned char intblk[4];
837 PUT_32BIT(intblk, i);
838 SHA_Bytes(s, intblk, 4);
842 * SSH2 packet construction functions.
844 static void ssh2_pkt_ensure(int length) {
845 if (pktout.maxlen < length) {
846 pktout.maxlen = length + 256;
847 pktout.data = (pktout.data == NULL ? smalloc(pktout.maxlen+APIEXTRA) :
848 srealloc(pktout.data, pktout.maxlen+APIEXTRA));
850 fatalbox("Out of memory");
853 static void ssh2_pkt_adddata(void *data, int len) {
854 pktout.length += len;
855 ssh2_pkt_ensure(pktout.length);
856 memcpy(pktout.data+pktout.length-len, data, len);
858 static void ssh2_pkt_addbyte(unsigned char byte) {
859 ssh2_pkt_adddata(&byte, 1);
861 static void ssh2_pkt_init(int pkt_type) {
863 ssh2_pkt_addbyte((unsigned char)pkt_type);
865 static void ssh2_pkt_addbool(unsigned char value) {
866 ssh2_pkt_adddata(&value, 1);
868 static void ssh2_pkt_adduint32(unsigned long value) {
871 ssh2_pkt_adddata(x, 4);
873 static void ssh2_pkt_addstring_start(void) {
874 ssh2_pkt_adduint32(0);
875 pktout.savedpos = pktout.length;
877 static void ssh2_pkt_addstring_str(char *data) {
878 ssh2_pkt_adddata(data, strlen(data));
879 PUT_32BIT(pktout.data + pktout.savedpos - 4,
880 pktout.length - pktout.savedpos);
882 static void ssh2_pkt_addstring_data(char *data, int len) {
883 ssh2_pkt_adddata(data, len);
884 PUT_32BIT(pktout.data + pktout.savedpos - 4,
885 pktout.length - pktout.savedpos);
887 static void ssh2_pkt_addstring(char *data) {
888 ssh2_pkt_addstring_start();
889 ssh2_pkt_addstring_str(data);
891 static char *ssh2_mpint_fmt(Bignum b, int *len) {
893 int i, n = (ssh1_bignum_bitcount(b)+7)/8;
896 fatalbox("out of memory");
898 for (i = 1; i <= n; i++)
899 p[i] = bignum_byte(b, n-i);
901 while (i <= n && p[i] == 0 && (p[i+1] & 0x80) == 0)
903 memmove(p, p+i, n+1-i);
907 static void ssh2_pkt_addmp(Bignum b) {
910 p = ssh2_mpint_fmt(b, &len);
911 ssh2_pkt_addstring_start();
912 ssh2_pkt_addstring_data(p, len);
917 * Construct an SSH2 final-form packet: compress it, encrypt it,
918 * put the MAC on it. Final packet, ready to be sent, is stored in
919 * pktout.data. Total length is returned.
921 static int ssh2_pkt_construct(void) {
922 int cipherblk, maclen, padding, i;
923 static unsigned long outgoing_sequence = 0;
926 * Compress packet payload.
929 debug(("Pre-compression payload:\r\n"));
930 for (i = 5; i < pktout.length; i++)
931 debug((" %02x", (unsigned char)pktout.data[i]));
935 unsigned char *newpayload;
937 if (cscomp && cscomp->compress(pktout.data+5, pktout.length-5,
938 &newpayload, &newlen)) {
940 ssh2_pkt_adddata(newpayload, newlen);
946 * Add padding. At least four bytes, and must also bring total
947 * length (minus MAC) up to a multiple of the block size.
949 cipherblk = cscipher ? cscipher->blksize : 8; /* block size */
950 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
952 padding += (cipherblk - (pktout.length + padding) % cipherblk) % cipherblk;
953 maclen = csmac ? csmac->len : 0;
954 ssh2_pkt_ensure(pktout.length + padding + maclen);
955 pktout.data[4] = padding;
956 for (i = 0; i < padding; i++)
957 pktout.data[pktout.length + i] = random_byte();
958 PUT_32BIT(pktout.data, pktout.length + padding - 4);
960 csmac->generate(pktout.data, pktout.length + padding,
962 outgoing_sequence++; /* whether or not we MACed */
965 debug(("Sending packet len=%d\r\n", pktout.length+padding));
966 for (i = 0; i < pktout.length+padding; i++)
967 debug((" %02x", (unsigned char)pktout.data[i]));
972 cscipher->encrypt(pktout.data, pktout.length + padding);
974 /* Ready-to-send packet starts at pktout.data. We return length. */
975 return pktout.length + padding + maclen;
979 * Construct and send an SSH2 packet immediately.
981 static void ssh2_pkt_send(void) {
982 int len = ssh2_pkt_construct();
983 sk_write(s, pktout.data, len);
987 * Construct an SSH2 packet and add it to a deferred data block.
988 * Useful for sending multiple packets in a single sk_write() call,
989 * to prevent a traffic-analysing listener from being able to work
990 * out the length of any particular packet (such as the password
993 * Note that because SSH2 sequence-numbers its packets, this can
994 * NOT be used as an m4-style `defer' allowing packets to be
995 * constructed in one order and sent in another.
997 static void ssh2_pkt_defer(void) {
998 int len = ssh2_pkt_construct();
999 if (deferred_len + len > deferred_size) {
1000 deferred_size = deferred_len + len + 128;
1001 deferred_send_data = srealloc(deferred_send_data, deferred_size);
1003 memcpy(deferred_send_data+deferred_len, pktout.data, len);
1004 deferred_len += len;
1008 * Send the whole deferred data block constructed by
1011 static void ssh2_pkt_defersend(void) {
1012 sk_write(s, deferred_send_data, deferred_len);
1013 deferred_len = deferred_size = 0;
1014 sfree(deferred_send_data);
1015 deferred_send_data = NULL;
1019 void bndebug(char *string, Bignum b) {
1022 p = ssh2_mpint_fmt(b, &len);
1023 debug(("%s", string));
1024 for (i = 0; i < len; i++)
1025 debug((" %02x", p[i]));
1031 static void sha_mpint(SHA_State *s, Bignum b) {
1034 p = ssh2_mpint_fmt(b, &len);
1035 sha_string(s, p, len);
1040 * SSH2 packet decode functions.
1042 static unsigned long ssh2_pkt_getuint32(void) {
1043 unsigned long value;
1044 if (pktin.length - pktin.savedpos < 4)
1045 return 0; /* arrgh, no way to decline (FIXME?) */
1046 value = GET_32BIT(pktin.data+pktin.savedpos);
1047 pktin.savedpos += 4;
1050 static void ssh2_pkt_getstring(char **p, int *length) {
1052 if (pktin.length - pktin.savedpos < 4)
1054 *length = GET_32BIT(pktin.data+pktin.savedpos);
1055 pktin.savedpos += 4;
1056 if (pktin.length - pktin.savedpos < *length)
1058 *p = pktin.data+pktin.savedpos;
1059 pktin.savedpos += *length;
1061 static Bignum ssh2_pkt_getmp(void) {
1066 ssh2_pkt_getstring(&p, &length);
1070 bombout(("internal error: Can't handle negative mpints"));
1073 b = bignum_from_bytes(p, length);
1077 static int do_ssh_init(unsigned char c) {
1079 static char version[10];
1080 static char vstring[80];
1081 static char vlog[sizeof(vstring)+20];
1086 /* Search for the string "SSH-" in the input. */
1089 static const int transS[] = { 1, 2, 2, 1 };
1090 static const int transH[] = { 0, 0, 3, 0 };
1091 static const int transminus[] = { 0, 0, 0, -1 };
1092 if (c == 'S') i = transS[i];
1093 else if (c == 'H') i = transH[i];
1094 else if (c == '-') i = transminus[i];
1098 crReturn(1); /* get another character */
1101 strcpy(vstring, "SSH-");
1105 crReturn(1); /* get another char */
1106 if (vsp < vstring+sizeof(vstring)-1)
1112 } else if (i < sizeof(version)-1)
1119 ssh_agentfwd_enabled = FALSE;
1120 rdpkt2_state.incoming_sequence = 0;
1123 sprintf(vlog, "Server version: %s", vstring);
1124 vlog[strcspn(vlog, "\r\n")] = '\0';
1128 * Server version "1.99" means we can choose whether we use v1
1129 * or v2 protocol. Choice is based on cfg.sshprot.
1131 if (ssh_versioncmp(version, cfg.sshprot == 1 ? "2.0" : "1.99") >= 0) {
1133 * This is a v2 server. Begin v2 protocol.
1135 char *verstring = "SSH-2.0-PuTTY";
1136 SHA_Init(&exhashbase);
1138 * Hash our version string and their version string.
1140 sha_string(&exhashbase, verstring, strlen(verstring));
1141 sha_string(&exhashbase, vstring, strcspn(vstring, "\r\n"));
1142 sprintf(vstring, "%s\n", verstring);
1143 sprintf(vlog, "We claim version: %s", verstring);
1145 logevent("Using SSH protocol version 2");
1146 sk_write(s, vstring, strlen(vstring));
1147 ssh_protocol = ssh2_protocol;
1149 s_rdpkt = ssh2_rdpkt;
1152 * This is a v1 server. Begin v1 protocol.
1154 sprintf(vstring, "SSH-%s-PuTTY\n",
1155 (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5"));
1156 sprintf(vlog, "We claim version: %s", vstring);
1157 vlog[strcspn(vlog, "\r\n")] = '\0';
1159 logevent("Using SSH protocol version 1");
1160 sk_write(s, vstring, strlen(vstring));
1161 ssh_protocol = ssh1_protocol;
1163 s_rdpkt = ssh1_rdpkt;
1165 ssh_state = SSH_STATE_BEFORE_SIZE;
1170 static void ssh_gotdata(unsigned char *data, int datalen)
1175 * To begin with, feed the characters one by one to the
1176 * protocol initialisation / selection function do_ssh_init().
1177 * When that returns 0, we're done with the initial greeting
1178 * exchange and can move on to packet discipline.
1183 crReturnV; /* more data please */
1184 ret = do_ssh_init(*data);
1191 * We emerge from that loop when the initial negotiation is
1192 * over and we have selected an s_rdpkt function. Now pass
1193 * everything to s_rdpkt, and then pass the resulting packets
1194 * to the proper protocol handler.
1199 while (datalen > 0) {
1200 if ( s_rdpkt(&data, &datalen) == 0 ) {
1201 ssh_protocol(NULL, 0, 1);
1202 if (ssh_state == SSH_STATE_CLOSED) {
1212 static int ssh_receive(Socket skt, int urgent, char *data, int len) {
1214 /* A socket error has occurred. */
1215 ssh_state = SSH_STATE_CLOSED;
1218 connection_fatal(data);
1221 /* Connection has closed. */
1222 ssh_state = SSH_STATE_CLOSED;
1227 ssh_gotdata (data, len);
1228 if (ssh_state == SSH_STATE_CLOSED) {
1239 * Connect to specified host and port.
1240 * Returns an error message, or NULL on success.
1241 * Also places the canonical host name into `realhost'.
1243 static char *connect_to_host(char *host, int port, char **realhost)
1252 savedhost = smalloc(1+strlen(host));
1254 fatalbox("Out of memory");
1255 strcpy(savedhost, host);
1258 port = 22; /* default ssh port */
1271 addr = sk_namelookup(host, realhost);
1272 if ( (err = sk_addr_error(addr)) )
1282 s = sk_new(addr, port, 0, 1, ssh_receive);
1283 if ( (err = sk_socket_error(s)) )
1287 sk_write(s, "connect ", 8);
1288 sk_write(s, FWhost, strlen(FWhost));
1291 sprintf(buf, " %d\n", FWport);
1292 sk_write(s, buf, strlen(buf));
1300 * Handle the key exchange and user authentication phases.
1302 static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
1305 unsigned char *rsabuf, *keystr1, *keystr2;
1306 unsigned char cookie[8];
1307 struct RSAKey servkey, hostkey;
1308 struct MD5Context md5c;
1309 static unsigned long supported_ciphers_mask, supported_auths_mask;
1310 static int tried_publickey;
1311 static unsigned char session_id[16];
1313 static char username[100];
1317 if (!ispkt) crWaitUntil(ispkt);
1319 if (pktin.type != SSH1_SMSG_PUBLIC_KEY) {
1320 bombout(("Public key packet not received"));
1324 logevent("Received public keys");
1326 memcpy(cookie, pktin.body, 8);
1328 i = makekey(pktin.body+8, &servkey, &keystr1, 0);
1329 j = makekey(pktin.body+8+i, &hostkey, &keystr2, 0);
1332 * Log the host key fingerprint.
1336 logevent("Host key fingerprint is:");
1337 strcpy(logmsg, " ");
1338 hostkey.comment = NULL;
1339 rsa_fingerprint(logmsg+strlen(logmsg), sizeof(logmsg)-strlen(logmsg),
1344 supported_ciphers_mask = GET_32BIT(pktin.body+12+i+j);
1345 supported_auths_mask = GET_32BIT(pktin.body+16+i+j);
1348 MD5Update(&md5c, keystr2, hostkey.bytes);
1349 MD5Update(&md5c, keystr1, servkey.bytes);
1350 MD5Update(&md5c, pktin.body, 8);
1351 MD5Final(session_id, &md5c);
1353 for (i=0; i<32; i++)
1354 session_key[i] = random_byte();
1356 len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
1358 rsabuf = smalloc(len);
1360 fatalbox("Out of memory");
1363 * Verify the host key.
1367 * First format the key into a string.
1369 int len = rsastr_len(&hostkey);
1370 char fingerprint[100];
1371 char *keystr = smalloc(len);
1373 fatalbox("Out of memory");
1374 rsastr_fmt(keystr, &hostkey);
1375 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
1376 verify_ssh_host_key(savedhost, savedport, "rsa", keystr, fingerprint);
1380 for (i=0; i<32; i++) {
1381 rsabuf[i] = session_key[i];
1383 rsabuf[i] ^= session_id[i];
1386 if (hostkey.bytes > servkey.bytes) {
1387 rsaencrypt(rsabuf, 32, &servkey);
1388 rsaencrypt(rsabuf, servkey.bytes, &hostkey);
1390 rsaencrypt(rsabuf, 32, &hostkey);
1391 rsaencrypt(rsabuf, hostkey.bytes, &servkey);
1394 logevent("Encrypted session key");
1396 switch (cfg.cipher) {
1397 case CIPHER_BLOWFISH: cipher_type = SSH_CIPHER_BLOWFISH; break;
1398 case CIPHER_DES: cipher_type = SSH_CIPHER_DES; break;
1399 case CIPHER_3DES: cipher_type = SSH_CIPHER_3DES; break;
1401 c_write("AES not supported in SSH1, falling back to 3DES\r\n", 49);
1402 cipher_type = SSH_CIPHER_3DES;
1405 if ((supported_ciphers_mask & (1 << cipher_type)) == 0) {
1406 c_write("Selected cipher not supported, falling back to 3DES\r\n", 53);
1407 cipher_type = SSH_CIPHER_3DES;
1409 switch (cipher_type) {
1410 case SSH_CIPHER_3DES: logevent("Using 3DES encryption"); break;
1411 case SSH_CIPHER_DES: logevent("Using single-DES encryption"); break;
1412 case SSH_CIPHER_BLOWFISH: logevent("Using Blowfish encryption"); break;
1415 send_packet(SSH1_CMSG_SESSION_KEY,
1416 PKT_CHAR, cipher_type,
1417 PKT_DATA, cookie, 8,
1418 PKT_CHAR, (len*8) >> 8, PKT_CHAR, (len*8) & 0xFF,
1419 PKT_DATA, rsabuf, len,
1423 logevent("Trying to enable encryption...");
1427 cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
1428 cipher_type == SSH_CIPHER_DES ? &ssh_des :
1430 cipher->sesskey(session_key);
1434 if (pktin.type != SSH1_SMSG_SUCCESS) {
1435 bombout(("Encryption not successfully enabled"));
1439 logevent("Successfully started encryption");
1445 if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
1446 c_write("login as: ", 10);
1449 crWaitUntil(!ispkt);
1450 while (inlen--) switch (c = *in++) {
1457 c_write("\b \b", 3);
1463 c_write("\b \b", 3);
1472 if (((c >= ' ' && c <= '~') ||
1473 ((unsigned char)c >= 160)) && pos < 40) {
1474 username[pos++] = c;
1481 username[strcspn(username, "\n\r")] = '\0';
1483 strncpy(username, cfg.username, 99);
1484 username[99] = '\0';
1487 send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END);
1489 char userlog[22+sizeof(username)];
1490 sprintf(userlog, "Sent username \"%s\"", username);
1492 if (flags & FLAG_INTERACTIVE &&
1493 (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
1494 strcat(userlog, "\r\n");
1495 c_write(userlog, strlen(userlog));
1502 tried_publickey = 0;
1504 while (pktin.type == SSH1_SMSG_FAILURE) {
1505 static char password[100];
1506 static char prompt[200];
1509 static int pwpkt_type;
1511 * Show password prompt, having first obtained it via a TIS
1512 * or CryptoCard exchange if we're doing TIS or CryptoCard
1515 pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
1516 if (agent_exists()) {
1518 * Attempt RSA authentication using Pageant.
1520 static unsigned char request[5], *response, *p;
1521 static int responselen;
1522 static int i, nkeys;
1523 static int authed = FALSE;
1526 logevent("Pageant is running. Requesting keys.");
1528 /* Request the keys held by the agent. */
1529 PUT_32BIT(request, 1);
1530 request[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES;
1531 agent_query(request, 5, &r, &responselen);
1532 response = (unsigned char *)r;
1535 nkeys = GET_32BIT(p); p += 4;
1536 { char buf[64]; sprintf(buf, "Pageant has %d keys", nkeys);
1538 for (i = 0; i < nkeys; i++) {
1539 static struct RSAKey key;
1540 static Bignum challenge;
1541 static char *commentp;
1542 static int commentlen;
1544 { char buf[64]; sprintf(buf, "Trying Pageant key #%d", i);
1547 p += ssh1_read_bignum(p, &key.exponent);
1548 p += ssh1_read_bignum(p, &key.modulus);
1549 commentlen = GET_32BIT(p); p += 4;
1550 commentp = p; p += commentlen;
1551 send_packet(SSH1_CMSG_AUTH_RSA,
1552 PKT_BIGNUM, key.modulus, PKT_END);
1554 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
1555 logevent("Key refused");
1558 logevent("Received RSA challenge");
1559 ssh1_read_bignum(pktin.body, &challenge);
1561 char *agentreq, *q, *ret;
1563 len = 1 + 4; /* message type, bit count */
1564 len += ssh1_bignum_length(key.exponent);
1565 len += ssh1_bignum_length(key.modulus);
1566 len += ssh1_bignum_length(challenge);
1567 len += 16; /* session id */
1568 len += 4; /* response format */
1569 agentreq = smalloc(4 + len);
1570 PUT_32BIT(agentreq, len);
1572 *q++ = SSH_AGENTC_RSA_CHALLENGE;
1573 PUT_32BIT(q, ssh1_bignum_bitcount(key.modulus));
1575 q += ssh1_write_bignum(q, key.exponent);
1576 q += ssh1_write_bignum(q, key.modulus);
1577 q += ssh1_write_bignum(q, challenge);
1578 memcpy(q, session_id, 16); q += 16;
1579 PUT_32BIT(q, 1); /* response format */
1580 agent_query(agentreq, len+4, &ret, &retlen);
1583 if (ret[4] == SSH_AGENT_RSA_RESPONSE) {
1584 logevent("Sending Pageant's response");
1585 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
1586 PKT_DATA, ret+5, 16, PKT_END);
1589 if (pktin.type == SSH1_SMSG_SUCCESS) {
1590 logevent("Pageant's response accepted");
1591 if (flags & FLAG_VERBOSE) {
1592 c_write("Authenticated using RSA key \"",
1594 c_write(commentp, commentlen);
1595 c_write("\" from agent\r\n", 14);
1599 logevent("Pageant's response not accepted");
1601 logevent("Pageant failed to answer challenge");
1605 logevent("No reply received from Pageant");
1608 freebn(key.exponent);
1609 freebn(key.modulus);
1618 if (*cfg.keyfile && !tried_publickey)
1619 pwpkt_type = SSH1_CMSG_AUTH_RSA;
1621 if (pktin.type == SSH1_SMSG_FAILURE &&
1623 (supported_auths_mask & (1<<SSH1_AUTH_TIS))) {
1624 pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
1625 logevent("Requested TIS authentication");
1626 send_packet(SSH1_CMSG_AUTH_TIS, PKT_END);
1628 if (pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
1629 logevent("TIS authentication declined");
1630 if (flags & FLAG_INTERACTIVE)
1631 c_write("TIS authentication refused.\r\n", 29);
1633 int challengelen = ((pktin.body[0] << 24) |
1634 (pktin.body[1] << 16) |
1635 (pktin.body[2] << 8) |
1637 logevent("Received TIS challenge");
1638 if (challengelen > sizeof(prompt)-1)
1639 challengelen = sizeof(prompt)-1; /* prevent overrun */
1640 memcpy(prompt, pktin.body+4, challengelen);
1641 prompt[challengelen] = '\0';
1644 if (pktin.type == SSH1_SMSG_FAILURE &&
1646 (supported_auths_mask & (1<<SSH1_AUTH_CCARD))) {
1647 pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
1648 logevent("Requested CryptoCard authentication");
1649 send_packet(SSH1_CMSG_AUTH_CCARD, PKT_END);
1651 if (pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
1652 logevent("CryptoCard authentication declined");
1653 c_write("CryptoCard authentication refused.\r\n", 29);
1655 int challengelen = ((pktin.body[0] << 24) |
1656 (pktin.body[1] << 16) |
1657 (pktin.body[2] << 8) |
1659 logevent("Received CryptoCard challenge");
1660 if (challengelen > sizeof(prompt)-1)
1661 challengelen = sizeof(prompt)-1; /* prevent overrun */
1662 memcpy(prompt, pktin.body+4, challengelen);
1663 strncpy(prompt + challengelen, "\r\nResponse : ",
1664 sizeof(prompt)-challengelen);
1665 prompt[sizeof(prompt)-1] = '\0';
1668 if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
1669 sprintf(prompt, "%.90s@%.90s's password: ",
1670 username, savedhost);
1672 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
1673 char *comment = NULL;
1674 if (flags & FLAG_VERBOSE)
1675 c_write("Trying public key authentication.\r\n", 35);
1676 if (!rsakey_encrypted(cfg.keyfile, &comment)) {
1677 if (flags & FLAG_VERBOSE)
1678 c_write("No passphrase required.\r\n", 25);
1681 sprintf(prompt, "Passphrase for key \"%.100s\": ", comment);
1685 if (ssh_get_password) {
1686 if (!ssh_get_password(prompt, password, sizeof(password))) {
1688 * get_password failed to get a password (for
1689 * example because one was supplied on the command
1690 * line which has already failed to work).
1693 logevent("No more passwords to try");
1694 ssh_state = SSH_STATE_CLOSED;
1698 c_write(prompt, strlen(prompt));
1702 crWaitUntil(!ispkt);
1703 while (inlen--) switch (c = *in++) {
1720 if (((c >= ' ' && c <= '~') ||
1721 ((unsigned char)c >= 160)) && pos < sizeof(password))
1722 password[pos++] = c;
1730 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
1732 * Try public key authentication with the specified
1735 static struct RSAKey pubkey;
1736 static Bignum challenge, response;
1738 static unsigned char buffer[32];
1740 tried_publickey = 1;
1741 i = loadrsakey(cfg.keyfile, &pubkey, NULL, password);
1743 c_write("Couldn't load public key from ", 30);
1744 c_write(cfg.keyfile, strlen(cfg.keyfile));
1745 c_write(".\r\n", 3);
1746 continue; /* go and try password */
1749 c_write("Wrong passphrase.\r\n", 19);
1750 tried_publickey = 0;
1751 continue; /* try again */
1755 * Send a public key attempt.
1757 send_packet(SSH1_CMSG_AUTH_RSA,
1758 PKT_BIGNUM, pubkey.modulus, PKT_END);
1761 if (pktin.type == SSH1_SMSG_FAILURE) {
1762 c_write("Server refused our public key.\r\n", 32);
1763 continue; /* go and try password */
1765 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
1766 bombout(("Bizarre response to offer of public key"));
1769 ssh1_read_bignum(pktin.body, &challenge);
1770 response = rsadecrypt(challenge, &pubkey);
1771 freebn(pubkey.private_exponent); /* burn the evidence */
1773 for (i = 0; i < 32; i++) {
1774 buffer[i] = bignum_byte(response, 31-i);
1778 MD5Update(&md5c, buffer, 32);
1779 MD5Update(&md5c, session_id, 16);
1780 MD5Final(buffer, &md5c);
1782 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
1783 PKT_DATA, buffer, 16, PKT_END);
1786 if (pktin.type == SSH1_SMSG_FAILURE) {
1787 if (flags & FLAG_VERBOSE)
1788 c_write("Failed to authenticate with our public key.\r\n",
1790 continue; /* go and try password */
1791 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
1792 bombout(("Bizarre response to RSA authentication response"));
1796 break; /* we're through! */
1798 send_packet(pwpkt_type, PKT_STR, password, PKT_END);
1800 logevent("Sent password");
1801 memset(password, 0, strlen(password));
1803 if (pktin.type == SSH1_SMSG_FAILURE) {
1804 if (flags & FLAG_VERBOSE)
1805 c_write("Access denied\r\n", 15);
1806 logevent("Authentication refused");
1807 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
1808 logevent("Received disconnect request");
1809 ssh_state = SSH_STATE_CLOSED;
1811 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
1812 bombout(("Strange packet received, type %d", pktin.type));
1817 logevent("Authentication successful");
1822 void sshfwd_close(struct ssh_channel *c) {
1824 if (ssh_version == 1) {
1825 send_packet(SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid, PKT_END);
1827 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
1828 ssh2_pkt_adduint32(c->remoteid);
1832 if (c->type == CHAN_X11) {
1834 logevent("X11 connection terminated");
1839 void sshfwd_write(struct ssh_channel *c, char *buf, int len) {
1840 if (ssh_version == 1) {
1841 send_packet(SSH1_MSG_CHANNEL_DATA,
1842 PKT_INT, c->remoteid,
1847 ssh2_add_channel_data(c, buf, len);
1852 static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) {
1857 while (!do_ssh1_login(in, inlen, ispkt)) {
1860 if (ssh_state == SSH_STATE_CLOSED)
1863 if (cfg.agentfwd && agent_exists()) {
1864 logevent("Requesting agent forwarding");
1865 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
1866 do { crReturnV; } while (!ispkt);
1867 if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
1868 bombout(("Protocol confusion"));
1870 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1871 logevent("Agent forwarding refused");
1873 logevent("Agent forwarding enabled");
1874 ssh_agentfwd_enabled = TRUE;
1878 if (cfg.x11_forward) {
1879 char proto[20], data[64];
1880 logevent("Requesting X11 forwarding");
1881 x11_invent_auth(proto, sizeof(proto), data, sizeof(data));
1882 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING,
1883 PKT_STR, proto, PKT_STR, data,
1886 do { crReturnV; } while (!ispkt);
1887 if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
1888 bombout(("Protocol confusion"));
1890 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1891 logevent("X11 forwarding refused");
1893 logevent("X11 forwarding enabled");
1894 ssh_X11_fwd_enabled = TRUE;
1899 send_packet(SSH1_CMSG_REQUEST_PTY,
1900 PKT_STR, cfg.termtype,
1901 PKT_INT, rows, PKT_INT, cols,
1902 PKT_INT, 0, PKT_INT, 0,
1905 ssh_state = SSH_STATE_INTERMED;
1906 do { crReturnV; } while (!ispkt);
1907 if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
1908 bombout(("Protocol confusion"));
1910 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1911 c_write("Server refused to allocate pty\r\n", 32);
1912 ssh_editing = ssh_echoing = 1;
1914 logevent("Allocated pty");
1916 ssh_editing = ssh_echoing = 1;
1919 if (cfg.compression) {
1920 send_packet(SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END);
1921 do { crReturnV; } while (!ispkt);
1922 if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
1923 bombout(("Protocol confusion"));
1925 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1926 c_write("Server refused to compress\r\n", 32);
1928 logevent("Started compression");
1929 ssh1_compressing = TRUE;
1930 zlib_compress_init();
1931 zlib_decompress_init();
1934 if (*cfg.remote_cmd)
1935 send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cfg.remote_cmd, PKT_END);
1937 send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END);
1938 logevent("Started session");
1940 ssh_state = SSH_STATE_SESSION;
1944 ssh_special(TS_EOF);
1946 ldisc_send(NULL, 0); /* cause ldisc to notice changes */
1948 ssh_channels = newtree234(ssh_channelcmp);
1952 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
1953 pktin.type == SSH1_SMSG_STDERR_DATA) {
1954 long len = GET_32BIT(pktin.body);
1955 from_backend(pktin.type == SSH1_SMSG_STDERR_DATA,
1957 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
1958 ssh_state = SSH_STATE_CLOSED;
1959 logevent("Received disconnect request");
1961 } else if (pktin.type == SSH1_SMSG_X11_OPEN) {
1962 /* Remote side is trying to open a channel to talk to our
1963 * X-Server. Give them back a local channel number. */
1965 struct ssh_channel *c, *d;
1968 logevent("Received X11 connect request");
1969 /* Refuse if X11 forwarding is disabled. */
1970 if (!ssh_X11_fwd_enabled) {
1971 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE,
1972 PKT_INT, GET_32BIT(pktin.body),
1974 logevent("Rejected X11 connect request");
1976 c = smalloc(sizeof(struct ssh_channel));
1978 if ( x11_init(&c->u.x11.s, cfg.x11_display, c) != NULL ) {
1979 logevent("opening X11 forward connection failed");
1981 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE,
1982 PKT_INT, GET_32BIT(pktin.body),
1985 logevent("opening X11 forward connection succeeded");
1986 for (i=1, d = first234(ssh_channels, &e); d; d = next234(&e)) {
1988 break; /* found a free number */
1991 c->remoteid = GET_32BIT(pktin.body);
1994 c->type = CHAN_X11; /* identify channel type */
1995 add234(ssh_channels, c);
1996 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
1997 PKT_INT, c->remoteid, PKT_INT, c->localid,
1999 logevent("Opened X11 forward channel");
2002 } else if (pktin.type == SSH1_SMSG_AGENT_OPEN) {
2003 /* Remote side is trying to open a channel to talk to our
2004 * agent. Give them back a local channel number. */
2006 struct ssh_channel *c;
2009 /* Refuse if agent forwarding is disabled. */
2010 if (!ssh_agentfwd_enabled) {
2011 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE,
2012 PKT_INT, GET_32BIT(pktin.body),
2016 for (c = first234(ssh_channels, &e); c; c = next234(&e)) {
2018 break; /* found a free number */
2021 c = smalloc(sizeof(struct ssh_channel));
2022 c->remoteid = GET_32BIT(pktin.body);
2025 c->type = CHAN_AGENT; /* identify channel type */
2026 c->u.a.lensofar = 0;
2027 add234(ssh_channels, c);
2028 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
2029 PKT_INT, c->remoteid, PKT_INT, c->localid,
2032 } else if (pktin.type == SSH1_MSG_CHANNEL_CLOSE ||
2033 pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
2034 /* Remote side closes a channel. */
2035 unsigned i = GET_32BIT(pktin.body);
2036 struct ssh_channel *c;
2037 c = find234(ssh_channels, &i, ssh_channelfind);
2040 closetype = (pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
2041 send_packet(pktin.type, PKT_INT, c->remoteid, PKT_END);
2042 if ((c->closes == 0) && (c->type == CHAN_X11)) {
2043 logevent("X11 connection closed");
2044 assert(c->u.x11.s != NULL);
2045 x11_close(c->u.x11.s);
2048 c->closes |= closetype;
2049 if (c->closes == 3) {
2050 del234(ssh_channels, c);
2054 } else if (pktin.type == SSH1_MSG_CHANNEL_DATA) {
2055 /* Data sent down one of our channels. */
2056 int i = GET_32BIT(pktin.body);
2057 int len = GET_32BIT(pktin.body+4);
2058 unsigned char *p = pktin.body+8;
2059 struct ssh_channel *c;
2060 c = find234(ssh_channels, &i, ssh_channelfind);
2064 x11_send(c->u.x11.s, p, len);
2067 /* Data for an agent message. Buffer it. */
2069 if (c->u.a.lensofar < 4) {
2070 int l = min(4 - c->u.a.lensofar, len);
2071 memcpy(c->u.a.msglen + c->u.a.lensofar, p, l);
2072 p += l; len -= l; c->u.a.lensofar += l;
2074 if (c->u.a.lensofar == 4) {
2075 c->u.a.totallen = 4 + GET_32BIT(c->u.a.msglen);
2076 c->u.a.message = smalloc(c->u.a.totallen);
2077 memcpy(c->u.a.message, c->u.a.msglen, 4);
2079 if (c->u.a.lensofar >= 4 && len > 0) {
2080 int l = min(c->u.a.totallen - c->u.a.lensofar, len);
2081 memcpy(c->u.a.message + c->u.a.lensofar, p, l);
2082 p += l; len -= l; c->u.a.lensofar += l;
2084 if (c->u.a.lensofar == c->u.a.totallen) {
2085 void *reply, *sentreply;
2087 agent_query(c->u.a.message, c->u.a.totallen,
2092 /* Fake SSH_AGENT_FAILURE. */
2093 sentreply = "\0\0\0\1\5";
2096 send_packet(SSH1_MSG_CHANNEL_DATA,
2097 PKT_INT, c->remoteid,
2099 PKT_DATA, sentreply, replylen,
2103 sfree(c->u.a.message);
2104 c->u.a.lensofar = 0;
2110 } else if (pktin.type == SSH1_SMSG_SUCCESS) {
2111 /* may be from EXEC_SHELL on some servers */
2112 } else if (pktin.type == SSH1_SMSG_FAILURE) {
2113 /* may be from EXEC_SHELL on some servers
2114 * if no pty is available or in other odd cases. Ignore */
2115 } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) {
2116 send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
2118 bombout(("Strange packet received: type %d", pktin.type));
2123 int len = min(inlen, 512);
2124 send_packet(SSH1_CMSG_STDIN_DATA,
2125 PKT_INT, len, PKT_DATA, in, len, PKT_END);
2136 * Utility routine for decoding comma-separated strings in KEXINIT.
2138 static int in_commasep_string(char *needle, char *haystack, int haylen) {
2139 int needlen = strlen(needle);
2142 * Is it at the start of the string?
2144 if (haylen >= needlen && /* haystack is long enough */
2145 !memcmp(needle, haystack, needlen) && /* initial match */
2146 (haylen == needlen || haystack[needlen] == ',')
2147 /* either , or EOS follows */
2151 * If not, search for the next comma and resume after that.
2152 * If no comma found, terminate.
2154 while (haylen > 0 && *haystack != ',')
2155 haylen--, haystack++;
2158 haylen--, haystack++; /* skip over comma itself */
2163 * SSH2 key creation method.
2165 static void ssh2_mkkey(Bignum K, char *H, char *sessid, char chr, char *keyspace) {
2167 /* First 20 bytes. */
2170 SHA_Bytes(&s, H, 20);
2171 SHA_Bytes(&s, &chr, 1);
2172 SHA_Bytes(&s, sessid, 20);
2173 SHA_Final(&s, keyspace);
2174 /* Next 20 bytes. */
2177 SHA_Bytes(&s, H, 20);
2178 SHA_Bytes(&s, keyspace, 20);
2179 SHA_Final(&s, keyspace+20);
2183 * Handle the SSH2 transport layer.
2185 static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt)
2187 static int i, j, len, nbits;
2189 static Bignum p, g, e, f, K;
2190 static int kex_init_value, kex_reply_value;
2191 static const struct ssh_mac **maclist;
2193 static const struct ssh2_cipher *cscipher_tobe = NULL;
2194 static const struct ssh2_cipher *sccipher_tobe = NULL;
2195 static const struct ssh_mac *csmac_tobe = NULL;
2196 static const struct ssh_mac *scmac_tobe = NULL;
2197 static const struct ssh_compress *cscomp_tobe = NULL;
2198 static const struct ssh_compress *sccomp_tobe = NULL;
2199 static char *hostkeydata, *sigdata, *keystr, *fingerprint;
2200 static int hostkeylen, siglen;
2201 static void *hkey; /* actual host key */
2202 static unsigned char exchange_hash[20];
2203 static unsigned char first_exchange_hash[20];
2204 static unsigned char keyspace[40];
2205 static const struct ssh2_ciphers *preferred_cipher;
2206 static const struct ssh_compress *preferred_comp;
2207 static int first_kex;
2214 * Set up the preferred cipher and compression.
2216 if (cfg.cipher == CIPHER_BLOWFISH) {
2217 preferred_cipher = &ssh2_blowfish;
2218 } else if (cfg.cipher == CIPHER_DES) {
2219 logevent("Single DES not supported in SSH2; using 3DES");
2220 preferred_cipher = &ssh2_3des;
2221 } else if (cfg.cipher == CIPHER_3DES) {
2222 preferred_cipher = &ssh2_3des;
2223 } else if (cfg.cipher == CIPHER_AES) {
2224 preferred_cipher = &ssh2_aes;
2226 /* Shouldn't happen, but we do want to initialise to _something_. */
2227 preferred_cipher = &ssh2_3des;
2229 if (cfg.compression)
2230 preferred_comp = &ssh_zlib;
2232 preferred_comp = &ssh_comp_none;
2235 * Be prepared to work around the buggy MAC problem.
2238 maclist = buggymacs, nmacs = lenof(buggymacs);
2240 maclist = macs, nmacs = lenof(macs);
2244 * Construct and send our key exchange packet.
2246 ssh2_pkt_init(SSH2_MSG_KEXINIT);
2247 for (i = 0; i < 16; i++)
2248 ssh2_pkt_addbyte((unsigned char)random_byte());
2249 /* List key exchange algorithms. */
2250 ssh2_pkt_addstring_start();
2251 for (i = 0; i < lenof(kex_algs); i++) {
2252 ssh2_pkt_addstring_str(kex_algs[i]->name);
2253 if (i < lenof(kex_algs)-1)
2254 ssh2_pkt_addstring_str(",");
2256 /* List server host key algorithms. */
2257 ssh2_pkt_addstring_start();
2258 for (i = 0; i < lenof(hostkey_algs); i++) {
2259 ssh2_pkt_addstring_str(hostkey_algs[i]->name);
2260 if (i < lenof(hostkey_algs)-1)
2261 ssh2_pkt_addstring_str(",");
2263 /* List client->server encryption algorithms. */
2264 ssh2_pkt_addstring_start();
2265 for (i = 0; i < lenof(ciphers)+1; i++) {
2266 const struct ssh2_ciphers *c = i==0 ? preferred_cipher : ciphers[i-1];
2267 for (j = 0; j < c->nciphers; j++) {
2268 ssh2_pkt_addstring_str(c->list[j]->name);
2269 if (i < lenof(ciphers) || j < c->nciphers-1)
2270 ssh2_pkt_addstring_str(",");
2273 /* List server->client encryption algorithms. */
2274 ssh2_pkt_addstring_start();
2275 for (i = 0; i < lenof(ciphers)+1; i++) {
2276 const struct ssh2_ciphers *c = i==0 ? preferred_cipher : ciphers[i-1];
2277 for (j = 0; j < c->nciphers; j++) {
2278 ssh2_pkt_addstring_str(c->list[j]->name);
2279 if (i < lenof(ciphers) || j < c->nciphers-1)
2280 ssh2_pkt_addstring_str(",");
2283 /* List client->server MAC algorithms. */
2284 ssh2_pkt_addstring_start();
2285 for (i = 0; i < nmacs; i++) {
2286 ssh2_pkt_addstring_str(maclist[i]->name);
2288 ssh2_pkt_addstring_str(",");
2290 /* List server->client MAC algorithms. */
2291 ssh2_pkt_addstring_start();
2292 for (i = 0; i < nmacs; i++) {
2293 ssh2_pkt_addstring_str(maclist[i]->name);
2295 ssh2_pkt_addstring_str(",");
2297 /* List client->server compression algorithms. */
2298 ssh2_pkt_addstring_start();
2299 for (i = 0; i < lenof(compressions)+1; i++) {
2300 const struct ssh_compress *c = i==0 ? preferred_comp : compressions[i-1];
2301 ssh2_pkt_addstring_str(c->name);
2302 if (i < lenof(compressions))
2303 ssh2_pkt_addstring_str(",");
2305 /* List server->client compression algorithms. */
2306 ssh2_pkt_addstring_start();
2307 for (i = 0; i < lenof(compressions)+1; i++) {
2308 const struct ssh_compress *c = i==0 ? preferred_comp : compressions[i-1];
2309 ssh2_pkt_addstring_str(c->name);
2310 if (i < lenof(compressions))
2311 ssh2_pkt_addstring_str(",");
2313 /* List client->server languages. Empty list. */
2314 ssh2_pkt_addstring_start();
2315 /* List server->client languages. Empty list. */
2316 ssh2_pkt_addstring_start();
2317 /* First KEX packet does _not_ follow, because we're not that brave. */
2318 ssh2_pkt_addbool(FALSE);
2320 ssh2_pkt_adduint32(0);
2322 exhash = exhashbase;
2323 sha_string(&exhash, pktout.data+5, pktout.length-5);
2327 if (!ispkt) crWaitUntil(ispkt);
2328 sha_string(&exhash, pktin.data+5, pktin.length-5);
2331 * Now examine the other side's KEXINIT to see what we're up
2334 if (pktin.type != SSH2_MSG_KEXINIT) {
2335 bombout(("expected key exchange packet from server"));
2338 kex = NULL; hostkey = NULL; cscipher_tobe = NULL; sccipher_tobe = NULL;
2339 csmac_tobe = NULL; scmac_tobe = NULL; cscomp_tobe = NULL; sccomp_tobe = NULL;
2340 pktin.savedpos += 16; /* skip garbage cookie */
2341 ssh2_pkt_getstring(&str, &len); /* key exchange algorithms */
2342 for (i = 0; i < lenof(kex_algs); i++) {
2343 if (in_commasep_string(kex_algs[i]->name, str, len)) {
2348 ssh2_pkt_getstring(&str, &len); /* host key algorithms */
2349 for (i = 0; i < lenof(hostkey_algs); i++) {
2350 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
2351 hostkey = hostkey_algs[i];
2355 ssh2_pkt_getstring(&str, &len); /* client->server cipher */
2356 for (i = 0; i < lenof(ciphers)+1; i++) {
2357 const struct ssh2_ciphers *c = i==0 ? preferred_cipher : ciphers[i-1];
2358 for (j = 0; j < c->nciphers; j++) {
2359 if (in_commasep_string(c->list[j]->name, str, len)) {
2360 cscipher_tobe = c->list[j];
2367 ssh2_pkt_getstring(&str, &len); /* server->client cipher */
2368 for (i = 0; i < lenof(ciphers)+1; i++) {
2369 const struct ssh2_ciphers *c = i==0 ? preferred_cipher : ciphers[i-1];
2370 for (j = 0; j < c->nciphers; j++) {
2371 if (in_commasep_string(c->list[j]->name, str, len)) {
2372 sccipher_tobe = c->list[j];
2379 ssh2_pkt_getstring(&str, &len); /* client->server mac */
2380 for (i = 0; i < nmacs; i++) {
2381 if (in_commasep_string(maclist[i]->name, str, len)) {
2382 csmac_tobe = maclist[i];
2386 ssh2_pkt_getstring(&str, &len); /* server->client mac */
2387 for (i = 0; i < nmacs; i++) {
2388 if (in_commasep_string(maclist[i]->name, str, len)) {
2389 scmac_tobe = maclist[i];
2393 ssh2_pkt_getstring(&str, &len); /* client->server compression */
2394 for (i = 0; i < lenof(compressions)+1; i++) {
2395 const struct ssh_compress *c = i==0 ? preferred_comp : compressions[i-1];
2396 if (in_commasep_string(c->name, str, len)) {
2401 ssh2_pkt_getstring(&str, &len); /* server->client compression */
2402 for (i = 0; i < lenof(compressions)+1; i++) {
2403 const struct ssh_compress *c = i==0 ? preferred_comp : compressions[i-1];
2404 if (in_commasep_string(c->name, str, len)) {
2411 * If we're doing Diffie-Hellman group exchange, start by
2412 * requesting a group.
2414 if (kex == &ssh_diffiehellman_gex) {
2417 logevent("Doing Diffie-Hellman group exchange");
2419 * Work out number of bits. We start with the maximum key
2420 * length of either cipher...
2422 csbits = cscipher_tobe->keylen;
2423 scbits = sccipher_tobe->keylen;
2424 nbits = (csbits > scbits ? csbits : scbits);
2425 /* The keys only have 160-bit entropy, since they're based on
2426 * a SHA-1 hash. So cap the key size at 160 bits. */
2427 if (nbits > 160) nbits = 160;
2429 * ... and then work out how big a DH group we will need to
2430 * allow that much data.
2432 nbits = 512 << ((nbits-1) / 64);
2433 ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST);
2434 ssh2_pkt_adduint32(nbits);
2438 if (pktin.type != SSH2_MSG_KEX_DH_GEX_GROUP) {
2439 bombout(("expected key exchange group packet from server"));
2442 p = ssh2_pkt_getmp();
2443 g = ssh2_pkt_getmp();
2444 dh_setup_group(p, g);
2445 kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
2446 kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
2449 kex_init_value = SSH2_MSG_KEXDH_INIT;
2450 kex_reply_value = SSH2_MSG_KEXDH_REPLY;
2453 logevent("Doing Diffie-Hellman key exchange");
2455 * Now generate and send e for Diffie-Hellman.
2458 ssh2_pkt_init(kex_init_value);
2463 if (pktin.type != kex_reply_value) {
2464 bombout(("expected key exchange reply packet from server"));
2467 ssh2_pkt_getstring(&hostkeydata, &hostkeylen);
2468 f = ssh2_pkt_getmp();
2469 ssh2_pkt_getstring(&sigdata, &siglen);
2473 sha_string(&exhash, hostkeydata, hostkeylen);
2474 if (kex == &ssh_diffiehellman_gex) {
2475 sha_uint32(&exhash, nbits);
2476 sha_mpint(&exhash, p);
2477 sha_mpint(&exhash, g);
2479 sha_mpint(&exhash, e);
2480 sha_mpint(&exhash, f);
2481 sha_mpint(&exhash, K);
2482 SHA_Final(&exhash, exchange_hash);
2487 debug(("Exchange hash is:\r\n"));
2488 for (i = 0; i < 20; i++)
2489 debug((" %02x", exchange_hash[i]));
2493 hkey = hostkey->newkey(hostkeydata, hostkeylen);
2494 if (!hostkey->verifysig(hkey, sigdata, siglen, exchange_hash, 20)) {
2495 bombout(("Server failed host key check"));
2500 * Expect SSH2_MSG_NEWKEYS from server.
2503 if (pktin.type != SSH2_MSG_NEWKEYS) {
2504 bombout(("expected new-keys packet from server"));
2509 * Authenticate remote host: verify host key. (We've already
2510 * checked the signature of the exchange hash.)
2512 keystr = hostkey->fmtkey(hkey);
2513 fingerprint = hostkey->fingerprint(hkey);
2514 verify_ssh_host_key(savedhost, savedport, hostkey->keytype,
2515 keystr, fingerprint);
2516 if (first_kex) { /* don't bother logging this in rekeys */
2517 logevent("Host key fingerprint is:");
2518 logevent(fingerprint);
2522 hostkey->freekey(hkey);
2525 * Send SSH2_MSG_NEWKEYS.
2527 ssh2_pkt_init(SSH2_MSG_NEWKEYS);
2531 * Create and initialise session keys.
2533 cscipher = cscipher_tobe;
2534 sccipher = sccipher_tobe;
2537 cscomp = cscomp_tobe;
2538 sccomp = sccomp_tobe;
2539 cscomp->compress_init();
2540 sccomp->decompress_init();
2542 * Set IVs after keys. Here we use the exchange hash from the
2543 * _first_ key exchange.
2546 memcpy(first_exchange_hash, exchange_hash, sizeof(exchange_hash));
2547 ssh2_mkkey(K, exchange_hash, first_exchange_hash, 'C', keyspace);
2548 cscipher->setcskey(keyspace);
2549 ssh2_mkkey(K, exchange_hash, first_exchange_hash, 'D', keyspace);
2550 sccipher->setsckey(keyspace);
2551 ssh2_mkkey(K, exchange_hash, first_exchange_hash, 'A', keyspace);
2552 cscipher->setcsiv(keyspace);
2553 ssh2_mkkey(K, exchange_hash, first_exchange_hash, 'B', keyspace);
2554 sccipher->setsciv(keyspace);
2555 ssh2_mkkey(K, exchange_hash, first_exchange_hash, 'E', keyspace);
2556 csmac->setcskey(keyspace);
2557 ssh2_mkkey(K, exchange_hash, first_exchange_hash, 'F', keyspace);
2558 scmac->setsckey(keyspace);
2561 * If this is the first key exchange phase, we must pass the
2562 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
2563 * wants to see it but because it will need time to initialise
2564 * itself before it sees an actual packet. In subsequent key
2565 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
2566 * it would only confuse the layer above.
2574 * Now we're encrypting. Begin returning 1 to the protocol main
2575 * function so that other things can run on top of the
2576 * transport. If we ever see a KEXINIT, we must go back to the
2579 while (!(ispkt && pktin.type == SSH2_MSG_KEXINIT)) {
2582 logevent("Server initiated key re-exchange");
2583 goto begin_key_exchange;
2589 * Add data to an SSH2 channel output buffer.
2591 static void ssh2_add_channel_data(struct ssh_channel *c, char *buf, int len) {
2592 if (c->v2.outbufsize <
2593 c->v2.outbuflen + len) {
2595 c->v2.outbuflen + len + 1024;
2596 c->v2.outbuffer = srealloc(c->v2.outbuffer,
2599 memcpy(c->v2.outbuffer + c->v2.outbuflen,
2601 c->v2.outbuflen += len;
2605 * Attempt to send data on an SSH2 channel.
2607 static void ssh2_try_send(struct ssh_channel *c) {
2608 while (c->v2.remwindow > 0 &&
2609 c->v2.outbuflen > 0) {
2610 unsigned len = c->v2.remwindow;
2611 if (len > c->v2.outbuflen)
2612 len = c->v2.outbuflen;
2613 if (len > c->v2.remmaxpkt)
2614 len = c->v2.remmaxpkt;
2615 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
2616 ssh2_pkt_adduint32(c->remoteid);
2617 ssh2_pkt_addstring_start();
2618 ssh2_pkt_addstring_data(c->v2.outbuffer, len);
2620 c->v2.outbuflen -= len;
2621 memmove(c->v2.outbuffer, c->v2.outbuffer+len,
2623 c->v2.remwindow -= len;
2628 * Handle the SSH2 userauth and connection layers.
2630 static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
2632 static unsigned long remote_winsize;
2633 static unsigned long remote_maxpkt;
2638 * Request userauth protocol, and await a response to it.
2640 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
2641 ssh2_pkt_addstring("ssh-userauth");
2643 crWaitUntilV(ispkt);
2644 if (pktin.type != SSH2_MSG_SERVICE_ACCEPT) {
2645 bombout(("Server refused user authentication protocol"));
2650 * FIXME: currently we support only password authentication.
2651 * (This places us technically in violation of the SSH2 spec.
2652 * We must fix this.)
2656 * Get a username and a password.
2658 static char username[100];
2659 static char password[100];
2663 if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
2664 c_write("login as: ", 10);
2667 crWaitUntilV(!ispkt);
2668 while (inlen--) switch (c = *in++) {
2675 c_write("\b \b", 3);
2681 c_write("\b \b", 3);
2690 if (((c >= ' ' && c <= '~') ||
2691 ((unsigned char)c >= 160)) && pos < 40) {
2692 username[pos++] = c;
2699 username[strcspn(username, "\n\r")] = '\0';
2702 strncpy(username, cfg.username, 99);
2703 username[99] = '\0';
2704 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
2705 sprintf(stuff, "Using username \"%s\".\r\n", username);
2706 c_write(stuff, strlen(stuff));
2710 if (ssh_get_password) {
2712 sprintf(prompt, "%.90s@%.90s's password: ", username, savedhost);
2713 if (!ssh_get_password(prompt, password, sizeof(password))) {
2715 * get_password failed to get a password (for
2716 * example because one was supplied on the command
2717 * line which has already failed to work).
2720 logevent("No more passwords to try");
2721 ssh_state = SSH_STATE_CLOSED;
2725 c_write("password: ", 10);
2730 crWaitUntilV(!ispkt);
2731 while (inlen--) switch (c = *in++) {
2748 if (((c >= ' ' && c <= '~') ||
2749 ((unsigned char)c >= 160)) && pos < 40)
2750 password[pos++] = c;
2758 * We send the password packet lumped tightly together with
2759 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
2760 * string long enough to make the total length of the two
2761 * packets constant. This should ensure that a passive
2762 * listener doing traffic analyis can't work out the length
2765 * For this to work, we need an assumption about the
2766 * maximum length of the password packet. I think 256 is
2767 * pretty conservative. Anyone using a password longer than
2768 * that probably doesn't have much to worry about from
2769 * people who find out how long their password is!
2771 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
2772 ssh2_pkt_addstring(username);
2773 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2774 ssh2_pkt_addstring("password");
2775 ssh2_pkt_addbool(FALSE);
2776 ssh2_pkt_addstring(password);
2779 * We'll include a string that's an exact multiple of the
2780 * cipher block size. If the cipher is NULL for some
2781 * reason, we don't do this trick at all because we gain
2786 ssh2_pkt_init(SSH2_MSG_IGNORE);
2787 ssh2_pkt_addstring_start();
2788 for (i = deferred_len; i <= 256; i += cscipher->blksize) {
2789 for (j = 0; j < cscipher->blksize; j++) {
2790 char c = (char)random_byte();
2791 ssh2_pkt_addstring_data(&c, 1);
2796 ssh2_pkt_defersend();
2798 crWaitUntilV(ispkt);
2799 if (pktin.type != SSH2_MSG_USERAUTH_SUCCESS) {
2800 c_write("Access denied\r\n", 15);
2801 logevent("Authentication refused");
2807 * Now we're authenticated for the connection protocol. The
2808 * connection protocol will automatically have started at this
2809 * point; there's no need to send SERVICE_REQUEST.
2813 * So now create a channel with a session in it.
2815 mainchan = smalloc(sizeof(struct ssh_channel));
2816 mainchan->localid = 100; /* as good as any */
2817 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
2818 ssh2_pkt_addstring("session");
2819 ssh2_pkt_adduint32(mainchan->localid);
2820 ssh2_pkt_adduint32(0x8000UL); /* our window size */
2821 ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
2823 crWaitUntilV(ispkt);
2824 if (pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
2825 bombout(("Server refused to open a session"));
2827 /* FIXME: error data comes back in FAILURE packet */
2829 if (ssh2_pkt_getuint32() != mainchan->localid) {
2830 bombout(("Server's channel confirmation cited wrong channel"));
2833 mainchan->remoteid = ssh2_pkt_getuint32();
2834 mainchan->type = CHAN_MAINSESSION;
2835 mainchan->closes = 0;
2836 mainchan->v2.remwindow = ssh2_pkt_getuint32();
2837 mainchan->v2.remmaxpkt = ssh2_pkt_getuint32();
2838 mainchan->v2.outbuffer = NULL;
2839 mainchan->v2.outbuflen = mainchan->v2.outbufsize = 0;
2840 ssh_channels = newtree234(ssh_channelcmp);
2841 add234(ssh_channels, mainchan);
2842 logevent("Opened channel for session");
2845 * Potentially enable X11 forwarding.
2847 if (cfg.x11_forward) {
2848 char proto[20], data[64];
2849 logevent("Requesting X11 forwarding");
2850 x11_invent_auth(proto, sizeof(proto), data, sizeof(data));
2851 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
2852 ssh2_pkt_adduint32(mainchan->remoteid);
2853 ssh2_pkt_addstring("x11-req");
2854 ssh2_pkt_addbool(1); /* want reply */
2855 ssh2_pkt_addbool(0); /* many connections */
2856 ssh2_pkt_addstring(proto);
2857 ssh2_pkt_addstring(data);
2858 ssh2_pkt_adduint32(0); /* screen number */
2862 crWaitUntilV(ispkt);
2863 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2864 unsigned i = ssh2_pkt_getuint32();
2865 struct ssh_channel *c;
2866 c = find234(ssh_channels, &i, ssh_channelfind);
2868 continue; /* nonexistent channel */
2869 c->v2.remwindow += ssh2_pkt_getuint32();
2871 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2873 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
2874 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
2875 bombout(("Server got confused by X11 forwarding request"));
2878 logevent("X11 forwarding refused");
2880 logevent("X11 forwarding enabled");
2881 ssh_X11_fwd_enabled = TRUE;
2886 * Now allocate a pty for the session.
2889 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
2890 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
2891 ssh2_pkt_addstring("pty-req");
2892 ssh2_pkt_addbool(1); /* want reply */
2893 ssh2_pkt_addstring(cfg.termtype);
2894 ssh2_pkt_adduint32(cols);
2895 ssh2_pkt_adduint32(rows);
2896 ssh2_pkt_adduint32(0); /* pixel width */
2897 ssh2_pkt_adduint32(0); /* pixel height */
2898 ssh2_pkt_addstring_start();
2899 ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
2901 ssh_state = SSH_STATE_INTERMED;
2904 crWaitUntilV(ispkt);
2905 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2906 unsigned i = ssh2_pkt_getuint32();
2907 struct ssh_channel *c;
2908 c = find234(ssh_channels, &i, ssh_channelfind);
2910 continue; /* nonexistent channel */
2911 c->v2.remwindow += ssh2_pkt_getuint32();
2913 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2915 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
2916 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
2917 bombout(("Server got confused by pty request"));
2920 c_write("Server refused to allocate pty\r\n", 32);
2921 ssh_editing = ssh_echoing = 1;
2923 logevent("Allocated pty");
2926 ssh_editing = ssh_echoing = 1;
2930 * Start a shell or a remote command.
2932 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
2933 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
2934 if (cfg.ssh_subsys) {
2935 ssh2_pkt_addstring("subsystem");
2936 ssh2_pkt_addbool(1); /* want reply */
2937 ssh2_pkt_addstring(cfg.remote_cmd);
2938 } else if (*cfg.remote_cmd) {
2939 ssh2_pkt_addstring("exec");
2940 ssh2_pkt_addbool(1); /* want reply */
2941 ssh2_pkt_addstring(cfg.remote_cmd);
2943 ssh2_pkt_addstring("shell");
2944 ssh2_pkt_addbool(1); /* want reply */
2948 crWaitUntilV(ispkt);
2949 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2950 unsigned i = ssh2_pkt_getuint32();
2951 struct ssh_channel *c;
2952 c = find234(ssh_channels, &i, ssh_channelfind);
2954 continue; /* nonexistent channel */
2955 c->v2.remwindow += ssh2_pkt_getuint32();
2957 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2958 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
2959 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
2960 bombout(("Server got confused by shell/command request"));
2963 bombout(("Server refused to start a shell/command"));
2966 logevent("Started a shell/command");
2969 ssh_state = SSH_STATE_SESSION;
2973 ssh_special(TS_EOF);
2978 ldisc_send(NULL, 0); /* cause ldisc to notice changes */
2981 static int try_send;
2985 if (pktin.type == SSH2_MSG_CHANNEL_DATA ||
2986 pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
2989 unsigned i = ssh2_pkt_getuint32();
2990 struct ssh_channel *c;
2991 c = find234(ssh_channels, &i, ssh_channelfind);
2993 continue; /* nonexistent channel */
2994 if (pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
2995 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR)
2996 continue; /* extended but not stderr */
2997 ssh2_pkt_getstring(&data, &length);
3000 case CHAN_MAINSESSION:
3001 from_backend(pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA,
3005 x11_send(c->u.x11.s, data, length);
3009 * Enlarge the window again at the remote
3010 * side, just in case it ever runs down and
3011 * they fail to send us any more data.
3013 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
3014 ssh2_pkt_adduint32(c->remoteid);
3015 ssh2_pkt_adduint32(length);
3018 } else if (pktin.type == SSH2_MSG_DISCONNECT) {
3019 ssh_state = SSH_STATE_CLOSED;
3020 logevent("Received disconnect message");
3022 } else if (pktin.type == SSH2_MSG_CHANNEL_REQUEST) {
3023 continue; /* exit status et al; ignore (FIXME?) */
3024 } else if (pktin.type == SSH2_MSG_CHANNEL_EOF) {
3025 unsigned i = ssh2_pkt_getuint32();
3026 struct ssh_channel *c;
3028 c = find234(ssh_channels, &i, ssh_channelfind);
3030 continue; /* nonexistent channel */
3032 if (c->type == CHAN_X11) {
3034 * Remote EOF on an X11 channel means we should
3035 * wrap up and close the channel ourselves.
3037 x11_close(c->u.x11.s);
3040 } else if (pktin.type == SSH2_MSG_CHANNEL_CLOSE) {
3041 unsigned i = ssh2_pkt_getuint32();
3042 struct ssh_channel *c;
3045 c = find234(ssh_channels, &i, ssh_channelfind);
3047 continue; /* nonexistent channel */
3048 if (c->closes == 0) {
3049 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
3050 ssh2_pkt_adduint32(c->remoteid);
3053 /* Do pre-close processing on the channel. */
3055 case CHAN_MAINSESSION:
3056 break; /* nothing to see here, move along */
3060 del234(ssh_channels, c);
3061 sfree(c->v2.outbuffer);
3065 * See if that was the last channel left open.
3067 c = first234(ssh_channels, &e);
3069 logevent("All channels closed. Disconnecting");
3070 ssh2_pkt_init(SSH2_MSG_DISCONNECT);
3071 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION);
3072 ssh2_pkt_addstring("All open channels closed");
3073 ssh2_pkt_addstring("en"); /* language tag */
3075 ssh_state = SSH_STATE_CLOSED;
3078 continue; /* remote sends close; ignore (FIXME) */
3079 } else if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
3080 unsigned i = ssh2_pkt_getuint32();
3081 struct ssh_channel *c;
3082 c = find234(ssh_channels, &i, ssh_channelfind);
3084 continue; /* nonexistent channel */
3085 mainchan->v2.remwindow += ssh2_pkt_getuint32();
3087 } else if (pktin.type == SSH2_MSG_CHANNEL_OPEN) {
3091 struct ssh_channel *c;
3092 ssh2_pkt_getstring(&type, &typelen);
3093 c = smalloc(sizeof(struct ssh_channel));
3095 if (typelen == 3 && !memcmp(type, "x11", 3)) {
3096 if (!ssh_X11_fwd_enabled)
3097 error = "X11 forwarding is not enabled";
3098 else if ( x11_init(&c->u.x11.s, cfg.x11_display, c) != NULL ) {
3099 error = "Unable to open an X11 connection";
3104 error = "Unsupported channel type requested";
3107 c->remoteid = ssh2_pkt_getuint32();
3109 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE);
3110 ssh2_pkt_adduint32(c->remoteid);
3111 ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED);
3112 ssh2_pkt_addstring(error);
3113 ssh2_pkt_addstring("en"); /* language tag */
3117 struct ssh_channel *d;
3121 for (i=1, d = first234(ssh_channels, &e); d;
3124 break; /* found a free number */
3129 c->v2.remwindow = ssh2_pkt_getuint32();
3130 c->v2.remmaxpkt = ssh2_pkt_getuint32();
3131 c->v2.outbuffer = NULL;
3132 c->v2.outbuflen = c->v2.outbufsize = 0;
3133 add234(ssh_channels, c);
3134 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
3135 ssh2_pkt_adduint32(c->remoteid);
3136 ssh2_pkt_adduint32(c->localid);
3137 ssh2_pkt_adduint32(0x8000UL); /* our window size */
3138 ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
3142 bombout(("Strange packet received: type %d", pktin.type));
3147 * We have spare data. Add it to the channel buffer.
3149 ssh2_add_channel_data(mainchan, in, inlen);
3154 struct ssh_channel *c;
3156 * Try to send data on all channels if we can.
3158 for (c = first234(ssh_channels, &e); c; c = next234(&e))
3167 * Handle the top-level SSH2 protocol.
3169 static void ssh2_protocol(unsigned char *in, int inlen, int ispkt)
3171 if (do_ssh2_transport(in, inlen, ispkt) == 0)
3173 do_ssh2_authconn(in, inlen, ispkt);
3177 * Called to set up the connection.
3179 * Returns an error message, or NULL on success.
3181 static char *ssh_init (char *host, int port, char **realhost) {
3185 if(crypto_startup() == 0)
3186 return "Microsoft high encryption pack not installed!";
3193 p = connect_to_host(host, port, realhost);
3201 * Called to send data down the Telnet connection.
3203 static void ssh_send (char *buf, int len) {
3204 if (s == NULL || ssh_protocol == NULL)
3207 ssh_protocol(buf, len, 0);
3211 * Called to set the size of the window from SSH's POV.
3213 static void ssh_size(void) {
3214 switch (ssh_state) {
3215 case SSH_STATE_BEFORE_SIZE:
3216 case SSH_STATE_PREPACKET:
3217 case SSH_STATE_CLOSED:
3218 break; /* do nothing */
3219 case SSH_STATE_INTERMED:
3220 size_needed = TRUE; /* buffer for later */
3222 case SSH_STATE_SESSION:
3224 if (ssh_version == 1) {
3225 send_packet(SSH1_CMSG_WINDOW_SIZE,
3226 PKT_INT, rows, PKT_INT, cols,
3227 PKT_INT, 0, PKT_INT, 0, PKT_END);
3229 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
3230 ssh2_pkt_adduint32(mainchan->remoteid);
3231 ssh2_pkt_addstring("window-change");
3232 ssh2_pkt_addbool(0);
3233 ssh2_pkt_adduint32(cols);
3234 ssh2_pkt_adduint32(rows);
3235 ssh2_pkt_adduint32(0);
3236 ssh2_pkt_adduint32(0);
3245 * Send Telnet special codes. TS_EOF is useful for `plink', so you
3246 * can send an EOF and collect resulting output (e.g. `plink
3249 static void ssh_special (Telnet_Special code) {
3250 if (code == TS_EOF) {
3251 if (ssh_state != SSH_STATE_SESSION) {
3253 * Buffer the EOF in case we are pre-SESSION, so we can
3254 * send it as soon as we reach SESSION.
3260 if (ssh_version == 1) {
3261 send_packet(SSH1_CMSG_EOF, PKT_END);
3263 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
3264 ssh2_pkt_adduint32(mainchan->remoteid);
3267 logevent("Sent EOF message");
3268 } else if (code == TS_PING) {
3269 if (ssh_state == SSH_STATE_CLOSED || ssh_state == SSH_STATE_PREPACKET)
3271 if (ssh_version == 1) {
3272 send_packet(SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
3274 ssh2_pkt_init(SSH2_MSG_IGNORE);
3275 ssh2_pkt_addstring_start();
3283 static Socket ssh_socket(void) { return s; }
3285 static int ssh_sendok(void) { return ssh_send_ok; }
3287 static int ssh_ldisc(int option) {
3288 if (option == LD_ECHO) return ssh_echoing;
3289 if (option == LD_EDIT) return ssh_editing;
3293 Backend ssh_backend = {