18 #define logevent(s) { logevent(s); \
19 if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \
20 fprintf(stderr, "%s\n", s); }
22 #define bombout(msg) ( ssh_state = SSH_STATE_CLOSED, sk_close(s), \
23 s = NULL, connection_fatal msg )
25 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
26 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
27 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
28 #define SSH1_CMSG_USER 4 /* 0x4 */
29 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
30 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
31 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
32 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
33 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
34 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
35 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
36 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
37 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
38 #define SSH1_SMSG_FAILURE 15 /* 0xf */
39 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
40 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
41 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
42 #define SSH1_CMSG_EOF 19 /* 0x13 */
43 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
44 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
45 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
46 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
47 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
48 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
49 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
50 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
51 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
52 #define SSH1_MSG_IGNORE 32 /* 0x20 */
53 #define SSH1_MSG_DEBUG 36 /* 0x24 */
54 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
55 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
56 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
57 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
58 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
59 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
61 #define SSH1_AUTH_TIS 5 /* 0x5 */
62 #define SSH1_AUTH_CCARD 16 /* 0x10 */
64 #define SSH_AGENTC_REQUEST_RSA_IDENTITIES 1 /* 0x1 */
65 #define SSH_AGENT_RSA_IDENTITIES_ANSWER 2 /* 0x2 */
66 #define SSH_AGENTC_RSA_CHALLENGE 3 /* 0x3 */
67 #define SSH_AGENT_RSA_RESPONSE 4 /* 0x4 */
68 #define SSH_AGENT_FAILURE 5 /* 0x5 */
69 #define SSH_AGENT_SUCCESS 6 /* 0x6 */
70 #define SSH_AGENTC_ADD_RSA_IDENTITY 7 /* 0x7 */
71 #define SSH_AGENTC_REMOVE_RSA_IDENTITY 8 /* 0x8 */
73 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
74 #define SSH2_MSG_IGNORE 2 /* 0x2 */
75 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
76 #define SSH2_MSG_DEBUG 4 /* 0x4 */
77 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
78 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
79 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
80 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
81 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
82 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
83 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
84 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
85 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
86 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
87 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
88 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
89 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
90 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
91 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
92 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
93 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
94 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
95 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
96 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
97 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
98 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
99 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
100 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
101 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
102 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
104 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
105 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
106 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
107 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
109 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
111 #define GET_32BIT(cp) \
112 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
113 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
114 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
115 ((unsigned long)(unsigned char)(cp)[3]))
117 #define PUT_32BIT(cp, value) { \
118 (cp)[0] = (unsigned char)((value) >> 24); \
119 (cp)[1] = (unsigned char)((value) >> 16); \
120 (cp)[2] = (unsigned char)((value) >> 8); \
121 (cp)[3] = (unsigned char)(value); }
123 enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM };
125 /* Coroutine mechanics for the sillier bits of the code */
126 #define crBegin1 static int crLine = 0;
127 #define crBegin2 switch(crLine) { case 0:;
128 #define crBegin crBegin1; crBegin2;
129 #define crFinish(z) } crLine = 0; return (z)
130 #define crFinishV } crLine = 0; return
131 #define crReturn(z) \
133 crLine=__LINE__; return (z); case __LINE__:;\
137 crLine=__LINE__; return; case __LINE__:;\
139 #define crStop(z) do{ crLine = 0; return (z); }while(0)
140 #define crStopV do{ crLine = 0; return; }while(0)
141 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
142 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
144 extern const struct ssh_cipher ssh_3des;
145 extern const struct ssh_cipher ssh_3des_ssh2;
146 extern const struct ssh_cipher ssh_des;
147 extern const struct ssh_cipher ssh_blowfish_ssh1;
148 extern const struct ssh_cipher ssh_blowfish_ssh2;
151 * Ciphers for SSH2. We miss out single-DES because it isn't
152 * supported; also 3DES and Blowfish are both done differently from
153 * SSH1. (3DES uses outer chaining; Blowfish has the opposite
154 * endianness and different-sized keys.)
156 const static struct ssh_cipher *ciphers[] = { &ssh_blowfish_ssh2, &ssh_3des_ssh2 };
158 extern const struct ssh_kex ssh_diffiehellman;
159 const static struct ssh_kex *kex_algs[] = { &ssh_diffiehellman };
161 extern const struct ssh_hostkey ssh_dss;
162 const static struct ssh_hostkey *hostkey_algs[] = { &ssh_dss };
164 extern const struct ssh_mac ssh_md5, ssh_sha1, ssh_sha1_buggy;
166 static void nullmac_key(unsigned char *key) { }
167 static void nullmac_generate(unsigned char *blk, int len, unsigned long seq) { }
168 static int nullmac_verify(unsigned char *blk, int len, unsigned long seq) { return 1; }
169 const static struct ssh_mac ssh_mac_none = {
170 nullmac_key, nullmac_key, nullmac_generate, nullmac_verify, "none", 0
172 const static struct ssh_mac *macs[] = {
173 &ssh_sha1, &ssh_md5, &ssh_mac_none };
174 const static struct ssh_mac *buggymacs[] = {
175 &ssh_sha1_buggy, &ssh_md5, &ssh_mac_none };
177 const static struct ssh_compress ssh_comp_none = {
180 const static struct ssh_compress *compressions[] = { &ssh_comp_none };
183 * 2-3-4 tree storing channels.
186 unsigned remoteid, localid;
190 struct ssh_agent_channel {
191 unsigned char *message;
192 unsigned char msglen[4];
193 int lensofar, totallen;
195 struct ssh2_data_channel {
196 unsigned char *outbuffer;
197 unsigned outbuflen, outbufsize;
198 unsigned remwindow, remmaxpkt;
212 static SHA_State exhash;
214 static Socket s = NULL;
216 static unsigned char session_key[32];
217 static const struct ssh_cipher *cipher = NULL;
218 static const struct ssh_cipher *cscipher = NULL;
219 static const struct ssh_cipher *sccipher = NULL;
220 static const struct ssh_mac *csmac = NULL;
221 static const struct ssh_mac *scmac = NULL;
222 static const struct ssh_compress *cscomp = NULL;
223 static const struct ssh_compress *sccomp = NULL;
224 static const struct ssh_kex *kex = NULL;
225 static const struct ssh_hostkey *hostkey = NULL;
226 int (*ssh_get_password)(const char *prompt, char *str, int maxlen) = NULL;
228 static char *savedhost;
229 static int savedport;
230 static int ssh_send_ok;
232 static tree234 *ssh_channels; /* indexed by local id */
233 static struct ssh_channel *mainchan; /* primary session channel */
236 SSH_STATE_BEFORE_SIZE,
240 } ssh_state = SSH_STATE_BEFORE_SIZE;
242 static int size_needed = FALSE;
244 static struct Packet pktin = { 0, 0, NULL, NULL, 0 };
245 static struct Packet pktout = { 0, 0, NULL, NULL, 0 };
247 static int ssh_version;
248 static void (*ssh_protocol)(unsigned char *in, int inlen, int ispkt);
249 static void ssh1_protocol(unsigned char *in, int inlen, int ispkt);
250 static void ssh2_protocol(unsigned char *in, int inlen, int ispkt);
251 static void ssh_size(void);
253 static int (*s_rdpkt)(unsigned char **data, int *datalen);
255 static struct rdpkt1_state_tag {
256 long len, pad, biglen, to_read;
257 unsigned long realcrc, gotcrc;
263 static struct rdpkt2_state_tag {
264 long len, pad, payload, packetlen, maclen;
267 unsigned long incoming_sequence;
270 static int ssh_channelcmp(void *av, void *bv) {
271 struct ssh_channel *a = (struct ssh_channel *)av;
272 struct ssh_channel *b = (struct ssh_channel *)bv;
273 if (a->localid < b->localid) return -1;
274 if (a->localid > b->localid) return +1;
277 static int ssh_channelfind(void *av, void *bv) {
278 unsigned *a = (unsigned *)av;
279 struct ssh_channel *b = (struct ssh_channel *)bv;
280 if (*a < b->localid) return -1;
281 if (*a > b->localid) return +1;
285 static void c_write (char *buf, int len) {
286 if ((flags & FLAG_STDERR)) {
288 for (i = 0; i < len; i++)
290 fputc(buf[i], stderr);
293 from_backend(1, buf, len);
297 * Collect incoming data in the incoming packet buffer.
298 * Decipher and verify the packet when it is completely read.
299 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
300 * Update the *data and *datalen variables.
301 * Return the additional nr of bytes needed, or 0 when
302 * a complete packet is available.
304 static int ssh1_rdpkt(unsigned char **data, int *datalen)
306 struct rdpkt1_state_tag *st = &rdpkt1_state;
315 for (st->i = st->len = 0; st->i < 4; st->i++) {
316 while ((*datalen) == 0)
318 st->len = (st->len << 8) + **data;
319 (*data)++, (*datalen)--;
323 if (st->len == 0x52656d6f) { /* "Remo"te server has closed ... */
324 st->len = 0x300; /* big enough to carry to end */
328 st->pad = 8 - (st->len % 8);
329 st->biglen = st->len + st->pad;
330 pktin.length = st->len - 5;
332 if (pktin.maxlen < st->biglen) {
333 pktin.maxlen = st->biglen;
334 pktin.data = (pktin.data == NULL ? malloc(st->biglen+APIEXTRA) :
335 realloc(pktin.data, st->biglen+APIEXTRA));
337 fatalbox("Out of memory");
340 st->to_read = st->biglen;
342 while (st->to_read > 0) {
343 st->chunk = st->to_read;
344 while ((*datalen) == 0)
345 crReturn(st->to_read);
346 if (st->chunk > (*datalen))
347 st->chunk = (*datalen);
348 memcpy(st->p, *data, st->chunk);
350 *datalen -= st->chunk;
352 st->to_read -= st->chunk;
356 cipher->decrypt(pktin.data, st->biglen);
358 debug(("Got packet len=%d pad=%d\r\n", st->len, st->pad));
359 for (st->i = 0; st->i < st->biglen; st->i++)
360 debug((" %02x", (unsigned char)pktin.data[st->i]));
364 pktin.type = pktin.data[st->pad];
365 pktin.body = pktin.data + st->pad + 1;
367 st->realcrc = crc32(pktin.data, st->biglen-4);
368 st->gotcrc = GET_32BIT(pktin.data+st->biglen-4);
369 if (st->gotcrc != st->realcrc) {
370 bombout(("Incorrect CRC received on packet"));
374 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
375 pktin.type == SSH1_SMSG_STDERR_DATA ||
376 pktin.type == SSH1_MSG_DEBUG ||
377 pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE ||
378 pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
379 long strlen = GET_32BIT(pktin.body);
380 if (strlen + 4 != pktin.length) {
381 bombout(("Received data packet with bogus string length"));
386 if (pktin.type == SSH1_MSG_DEBUG) {
387 /* log debug message */
389 int strlen = GET_32BIT(pktin.body);
390 strcpy(buf, "Remote: ");
391 if (strlen > 70) strlen = 70;
392 memcpy(buf+8, pktin.body+4, strlen);
393 buf[8+strlen] = '\0';
396 } else if (pktin.type == SSH1_MSG_IGNORE) {
404 static int ssh2_rdpkt(unsigned char **data, int *datalen)
406 struct rdpkt2_state_tag *st = &rdpkt2_state;
414 st->cipherblk = sccipher->blksize;
417 if (st->cipherblk < 8)
420 if (pktin.maxlen < st->cipherblk) {
421 pktin.maxlen = st->cipherblk;
422 pktin.data = (pktin.data == NULL ? malloc(st->cipherblk+APIEXTRA) :
423 realloc(pktin.data, st->cipherblk+APIEXTRA));
425 fatalbox("Out of memory");
429 * Acquire and decrypt the first block of the packet. This will
430 * contain the length and padding details.
432 for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
433 while ((*datalen) == 0)
434 crReturn(st->cipherblk-st->i);
435 pktin.data[st->i] = *(*data)++;
439 if (!memcmp(pktin.data, "Remo", 4)) {/* "Remo"te server has closed ... */
444 sccipher->decrypt(pktin.data, st->cipherblk);
447 * Now get the length and padding figures.
449 st->len = GET_32BIT(pktin.data);
450 st->pad = pktin.data[4];
453 * This enables us to deduce the payload length.
455 st->payload = st->len - st->pad - 1;
457 pktin.length = st->payload + 5;
460 * So now we can work out the total packet length.
462 st->packetlen = st->len + 4;
463 st->maclen = scmac ? scmac->len : 0;
466 * Adjust memory allocation if packet is too big.
468 if (pktin.maxlen < st->packetlen+st->maclen) {
469 pktin.maxlen = st->packetlen+st->maclen;
470 pktin.data = (pktin.data == NULL ? malloc(pktin.maxlen+APIEXTRA) :
471 realloc(pktin.data, pktin.maxlen+APIEXTRA));
473 fatalbox("Out of memory");
477 * Read and decrypt the remainder of the packet.
479 for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen; st->i++) {
480 while ((*datalen) == 0)
481 crReturn(st->packetlen + st->maclen - st->i);
482 pktin.data[st->i] = *(*data)++;
485 /* Decrypt everything _except_ the MAC. */
487 sccipher->decrypt(pktin.data + st->cipherblk,
488 st->packetlen - st->cipherblk);
491 debug(("Got packet len=%d pad=%d\r\n", st->len, st->pad));
492 for (st->i = 0; st->i < st->packetlen; st->i++)
493 debug((" %02x", (unsigned char)pktin.data[st->i]));
500 if (scmac && !scmac->verify(pktin.data, st->len+4, st->incoming_sequence)) {
501 bombout(("Incorrect MAC received on packet"));
504 st->incoming_sequence++; /* whether or not we MACed */
507 pktin.type = pktin.data[5];
509 if (pktin.type == SSH2_MSG_IGNORE || pktin.type == SSH2_MSG_DEBUG)
510 goto next_packet; /* FIXME: print DEBUG message */
515 static void s_wrpkt_start(int type, int len) {
518 len += 5; /* type and CRC */
522 pktout.length = len-5;
523 if (pktout.maxlen < biglen) {
524 pktout.maxlen = biglen;
526 /* Allocate enough buffer space for extra block
527 * for MS CryptEncrypt() */
528 pktout.data = (pktout.data == NULL ? malloc(biglen+12) :
529 realloc(pktout.data, biglen+12));
531 pktout.data = (pktout.data == NULL ? malloc(biglen+4) :
532 realloc(pktout.data, biglen+4));
535 fatalbox("Out of memory");
539 pktout.body = pktout.data+4+pad+1;
542 static void s_wrpkt(void) {
543 int pad, len, biglen, i;
546 len = pktout.length + 5; /* type and CRC */
550 pktout.body[-1] = pktout.type;
551 for (i=0; i<pad; i++)
552 pktout.data[i+4] = random_byte();
553 crc = crc32(pktout.data+4, biglen-4);
554 PUT_32BIT(pktout.data+biglen, crc);
555 PUT_32BIT(pktout.data, len);
558 debug(("Sending packet len=%d\r\n", biglen+4));
559 for (i = 0; i < biglen+4; i++)
560 debug((" %02x", (unsigned char)pktout.data[i]));
564 cipher->encrypt(pktout.data+4, biglen);
566 sk_write(s, pktout.data, biglen+4);
570 * Construct a packet with the specified contents and
571 * send it to the server.
573 static void send_packet(int pkttype, ...)
576 unsigned char *p, *argp, argchar;
577 unsigned long argint;
578 int pktlen, argtype, arglen;
582 va_start(args, pkttype);
583 while ((argtype = va_arg(args, int)) != PKT_END) {
586 (void) va_arg(args, int);
590 (void) va_arg(args, char);
594 (void) va_arg(args, unsigned char *);
595 arglen = va_arg(args, int);
599 argp = va_arg(args, unsigned char *);
600 arglen = strlen(argp);
601 pktlen += 4 + arglen;
604 bn = va_arg(args, Bignum);
605 pktlen += ssh1_bignum_length(bn);
613 s_wrpkt_start(pkttype, pktlen);
616 va_start(args, pkttype);
617 while ((argtype = va_arg(args, int)) != PKT_END) {
620 argint = va_arg(args, int);
621 PUT_32BIT(p, argint);
625 argchar = va_arg(args, unsigned char);
630 argp = va_arg(args, unsigned char *);
631 arglen = va_arg(args, int);
632 memcpy(p, argp, arglen);
636 argp = va_arg(args, unsigned char *);
637 arglen = strlen(argp);
638 PUT_32BIT(p, arglen);
639 memcpy(p + 4, argp, arglen);
643 bn = va_arg(args, Bignum);
644 p += ssh1_write_bignum(p, bn);
653 static int ssh_versioncmp(char *a, char *b) {
655 unsigned long av, bv;
657 av = strtoul(a, &ae, 10);
658 bv = strtoul(b, &be, 10);
659 if (av != bv) return (av < bv ? -1 : +1);
660 if (*ae == '.') ae++;
661 if (*be == '.') be++;
662 av = strtoul(ae, &ae, 10);
663 bv = strtoul(be, &be, 10);
664 if (av != bv) return (av < bv ? -1 : +1);
670 * Utility routine for putting an SSH-protocol `string' into a SHA
674 static void sha_string(SHA_State *s, void *str, int len) {
675 unsigned char lenblk[4];
676 PUT_32BIT(lenblk, len);
677 SHA_Bytes(s, lenblk, 4);
678 SHA_Bytes(s, str, len);
682 * SSH2 packet construction functions.
684 static void ssh2_pkt_adddata(void *data, int len) {
685 pktout.length += len;
686 if (pktout.maxlen < pktout.length) {
687 pktout.maxlen = pktout.length + 256;
688 pktout.data = (pktout.data == NULL ? malloc(pktout.maxlen+APIEXTRA) :
689 realloc(pktout.data, pktout.maxlen+APIEXTRA));
691 fatalbox("Out of memory");
693 memcpy(pktout.data+pktout.length-len, data, len);
695 static void ssh2_pkt_addbyte(unsigned char byte) {
696 ssh2_pkt_adddata(&byte, 1);
698 static void ssh2_pkt_init(int pkt_type) {
700 ssh2_pkt_addbyte((unsigned char)pkt_type);
702 static void ssh2_pkt_addbool(unsigned char value) {
703 ssh2_pkt_adddata(&value, 1);
705 static void ssh2_pkt_adduint32(unsigned long value) {
708 ssh2_pkt_adddata(x, 4);
710 static void ssh2_pkt_addstring_start(void) {
711 ssh2_pkt_adduint32(0);
712 pktout.savedpos = pktout.length;
714 static void ssh2_pkt_addstring_str(char *data) {
715 ssh2_pkt_adddata(data, strlen(data));
716 PUT_32BIT(pktout.data + pktout.savedpos - 4,
717 pktout.length - pktout.savedpos);
719 static void ssh2_pkt_addstring_data(char *data, int len) {
720 ssh2_pkt_adddata(data, len);
721 PUT_32BIT(pktout.data + pktout.savedpos - 4,
722 pktout.length - pktout.savedpos);
724 static void ssh2_pkt_addstring(char *data) {
725 ssh2_pkt_addstring_start();
726 ssh2_pkt_addstring_str(data);
728 static char *ssh2_mpint_fmt(Bignum b, int *len) {
731 p = malloc(n * 2 + 1);
733 fatalbox("out of memory");
735 for (i = 0; i < n; i++) {
736 p[i*2+1] = (b[n-i] >> 8) & 0xFF;
737 p[i*2+2] = (b[n-i] ) & 0xFF;
740 while (p[i] == 0 && (p[i+1] & 0x80) == 0)
742 memmove(p, p+i, n*2+1-i);
746 static void ssh2_pkt_addmp(Bignum b) {
749 p = ssh2_mpint_fmt(b, &len);
750 ssh2_pkt_addstring_start();
751 ssh2_pkt_addstring_data(p, len);
754 static void ssh2_pkt_send(void) {
755 int cipherblk, maclen, padding, i;
756 static unsigned long outgoing_sequence = 0;
759 * Add padding. At least four bytes, and must also bring total
760 * length (minus MAC) up to a multiple of the block size.
762 cipherblk = cipher ? cipher->blksize : 8; /* block size */
763 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
765 padding += (cipherblk - (pktout.length + padding) % cipherblk) % cipherblk;
766 pktout.data[4] = padding;
767 for (i = 0; i < padding; i++)
768 pktout.data[pktout.length + i] = random_byte();
769 PUT_32BIT(pktout.data, pktout.length + padding - 4);
771 csmac->generate(pktout.data, pktout.length + padding,
773 outgoing_sequence++; /* whether or not we MACed */
776 debug(("Sending packet len=%d\r\n", pktout.length+padding));
777 for (i = 0; i < pktout.length+padding; i++)
778 debug((" %02x", (unsigned char)pktout.data[i]));
783 cscipher->encrypt(pktout.data, pktout.length + padding);
784 maclen = csmac ? csmac->len : 0;
786 sk_write(s, pktout.data, pktout.length + padding + maclen);
790 void bndebug(char *string, Bignum b) {
793 p = ssh2_mpint_fmt(b, &len);
794 debug(("%s", string));
795 for (i = 0; i < len; i++)
796 debug((" %02x", p[i]));
802 static void sha_mpint(SHA_State *s, Bignum b) {
805 p = ssh2_mpint_fmt(b, &len);
806 sha_string(s, p, len);
811 * SSH2 packet decode functions.
813 static unsigned long ssh2_pkt_getuint32(void) {
815 if (pktin.length - pktin.savedpos < 4)
816 return 0; /* arrgh, no way to decline (FIXME?) */
817 value = GET_32BIT(pktin.data+pktin.savedpos);
821 static void ssh2_pkt_getstring(char **p, int *length) {
823 if (pktin.length - pktin.savedpos < 4)
825 *length = GET_32BIT(pktin.data+pktin.savedpos);
827 if (pktin.length - pktin.savedpos < *length)
829 *p = pktin.data+pktin.savedpos;
830 pktin.savedpos += *length;
832 static Bignum ssh2_pkt_getmp(void) {
837 ssh2_pkt_getstring(&p, &length);
841 bombout(("internal error: Can't handle negative mpints"));
844 b = newbn((length+1)/2);
845 for (i = 0; i < length; i++) {
848 b[j/2+1] |= ((unsigned char)p[i]) << 8;
850 b[j/2+1] |= ((unsigned char)p[i]);
855 static int do_ssh_init(unsigned char c) {
857 static char version[10];
858 static char vstring[80];
859 static char vlog[sizeof(vstring)+20];
864 /* Search for the string "SSH-" in the input. */
867 static const int transS[] = { 1, 2, 2, 1 };
868 static const int transH[] = { 0, 0, 3, 0 };
869 static const int transminus[] = { 0, 0, 0, -1 };
870 if (c == 'S') i = transS[i];
871 else if (c == 'H') i = transH[i];
872 else if (c == '-') i = transminus[i];
876 crReturn(1); /* get another character */
879 strcpy(vstring, "SSH-");
883 crReturn(1); /* get another char */
884 if (vsp < vstring+sizeof(vstring)-1)
890 } else if (i < sizeof(version)-1)
897 rdpkt2_state.incoming_sequence = 0;
900 sprintf(vlog, "Server version: %s", vstring);
901 vlog[strcspn(vlog, "\r\n")] = '\0';
905 * Server version "1.99" means we can choose whether we use v1
906 * or v2 protocol. Choice is based on cfg.sshprot.
908 if (ssh_versioncmp(version, cfg.sshprot == 1 ? "2.0" : "1.99") >= 0) {
910 * This is a v2 server. Begin v2 protocol.
912 char *verstring = "SSH-2.0-PuTTY";
915 * Hash our version string and their version string.
917 sha_string(&exhash, verstring, strlen(verstring));
918 sha_string(&exhash, vstring, strcspn(vstring, "\r\n"));
919 sprintf(vstring, "%s\n", verstring);
920 sprintf(vlog, "We claim version: %s", verstring);
922 logevent("Using SSH protocol version 2");
923 sk_write(s, vstring, strlen(vstring));
924 ssh_protocol = ssh2_protocol;
926 s_rdpkt = ssh2_rdpkt;
929 * This is a v1 server. Begin v1 protocol.
931 sprintf(vstring, "SSH-%s-PuTTY\n",
932 (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5"));
933 sprintf(vlog, "We claim version: %s", vstring);
934 vlog[strcspn(vlog, "\r\n")] = '\0';
936 logevent("Using SSH protocol version 1");
937 sk_write(s, vstring, strlen(vstring));
938 ssh_protocol = ssh1_protocol;
940 s_rdpkt = ssh1_rdpkt;
946 static void ssh_gotdata(unsigned char *data, int datalen)
951 * To begin with, feed the characters one by one to the
952 * protocol initialisation / selection function do_ssh_init().
953 * When that returns 0, we're done with the initial greeting
954 * exchange and can move on to packet discipline.
959 crReturnV; /* more data please */
960 ret = do_ssh_init(*data);
967 * We emerge from that loop when the initial negotiation is
968 * over and we have selected an s_rdpkt function. Now pass
969 * everything to s_rdpkt, and then pass the resulting packets
970 * to the proper protocol handler.
975 while (datalen > 0) {
976 if ( s_rdpkt(&data, &datalen) == 0 ) {
977 ssh_protocol(NULL, 0, 1);
978 if (ssh_state == SSH_STATE_CLOSED) {
988 static int ssh_receive(Socket s, int urgent, char *data, int len) {
990 /* Connection has closed. */
995 ssh_gotdata (data, len);
996 if (ssh_state == SSH_STATE_CLOSED) {
1007 * Connect to specified host and port.
1008 * Returns an error message, or NULL on success.
1009 * Also places the canonical host name into `realhost'.
1011 static char *connect_to_host(char *host, int port, char **realhost)
1020 savedhost = malloc(1+strlen(host));
1022 fatalbox("Out of memory");
1023 strcpy(savedhost, host);
1026 port = 22; /* default ssh port */
1039 addr = sk_namelookup(host, realhost);
1040 if ( (err = sk_addr_error(addr)) )
1050 s = sk_new(addr, port, ssh_receive);
1051 if ( (err = sk_socket_error(s)) )
1055 sk_write(s, "connect ", 8);
1056 sk_write(s, FWhost, strlen(FWhost));
1059 sprintf(buf, " %d\n", FWport);
1060 sk_write(s, buf, strlen(buf));
1068 * Handle the key exchange and user authentication phases.
1070 static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
1073 unsigned char *rsabuf, *keystr1, *keystr2;
1074 unsigned char cookie[8];
1075 struct RSAKey servkey, hostkey;
1076 struct MD5Context md5c;
1077 static unsigned long supported_ciphers_mask, supported_auths_mask;
1078 static int tried_publickey;
1079 static unsigned char session_id[16];
1081 static char username[100];
1085 if (!ispkt) crWaitUntil(ispkt);
1087 if (pktin.type != SSH1_SMSG_PUBLIC_KEY) {
1088 bombout(("Public key packet not received"));
1092 logevent("Received public keys");
1094 memcpy(cookie, pktin.body, 8);
1096 i = makekey(pktin.body+8, &servkey, &keystr1, 0);
1097 j = makekey(pktin.body+8+i, &hostkey, &keystr2, 0);
1100 * Log the host key fingerprint.
1104 logevent("Host key fingerprint is:");
1105 strcpy(logmsg, " ");
1106 hostkey.comment = NULL;
1107 rsa_fingerprint(logmsg+strlen(logmsg), sizeof(logmsg)-strlen(logmsg),
1112 supported_ciphers_mask = GET_32BIT(pktin.body+12+i+j);
1113 supported_auths_mask = GET_32BIT(pktin.body+16+i+j);
1116 MD5Update(&md5c, keystr2, hostkey.bytes);
1117 MD5Update(&md5c, keystr1, servkey.bytes);
1118 MD5Update(&md5c, pktin.body, 8);
1119 MD5Final(session_id, &md5c);
1121 for (i=0; i<32; i++)
1122 session_key[i] = random_byte();
1124 len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
1126 rsabuf = malloc(len);
1128 fatalbox("Out of memory");
1131 * Verify the host key.
1135 * First format the key into a string.
1137 int len = rsastr_len(&hostkey);
1138 char fingerprint[100];
1139 char *keystr = malloc(len);
1141 fatalbox("Out of memory");
1142 rsastr_fmt(keystr, &hostkey);
1143 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
1144 verify_ssh_host_key(savedhost, savedport, "rsa", keystr, fingerprint);
1148 for (i=0; i<32; i++) {
1149 rsabuf[i] = session_key[i];
1151 rsabuf[i] ^= session_id[i];
1154 if (hostkey.bytes > servkey.bytes) {
1155 rsaencrypt(rsabuf, 32, &servkey);
1156 rsaencrypt(rsabuf, servkey.bytes, &hostkey);
1158 rsaencrypt(rsabuf, 32, &hostkey);
1159 rsaencrypt(rsabuf, hostkey.bytes, &servkey);
1162 logevent("Encrypted session key");
1164 cipher_type = cfg.cipher == CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH :
1165 cfg.cipher == CIPHER_DES ? SSH_CIPHER_DES :
1167 if ((supported_ciphers_mask & (1 << cipher_type)) == 0) {
1168 c_write("Selected cipher not supported, falling back to 3DES\r\n", 53);
1169 cipher_type = SSH_CIPHER_3DES;
1171 switch (cipher_type) {
1172 case SSH_CIPHER_3DES: logevent("Using 3DES encryption"); break;
1173 case SSH_CIPHER_DES: logevent("Using single-DES encryption"); break;
1174 case SSH_CIPHER_BLOWFISH: logevent("Using Blowfish encryption"); break;
1177 send_packet(SSH1_CMSG_SESSION_KEY,
1178 PKT_CHAR, cipher_type,
1179 PKT_DATA, cookie, 8,
1180 PKT_CHAR, (len*8) >> 8, PKT_CHAR, (len*8) & 0xFF,
1181 PKT_DATA, rsabuf, len,
1185 logevent("Trying to enable encryption...");
1189 cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
1190 cipher_type == SSH_CIPHER_DES ? &ssh_des :
1192 cipher->sesskey(session_key);
1196 if (pktin.type != SSH1_SMSG_SUCCESS) {
1197 bombout(("Encryption not successfully enabled"));
1201 logevent("Successfully started encryption");
1207 if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
1208 c_write("login as: ", 10);
1211 crWaitUntil(!ispkt);
1212 while (inlen--) switch (c = *in++) {
1219 c_write("\b \b", 3);
1225 c_write("\b \b", 3);
1234 if (((c >= ' ' && c <= '~') ||
1235 ((unsigned char)c >= 160)) && pos < 40) {
1236 username[pos++] = c;
1243 username[strcspn(username, "\n\r")] = '\0';
1246 strncpy(username, cfg.username, 99);
1247 username[99] = '\0';
1248 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
1249 sprintf(stuff, "Sent username \"%s\".\r\n", username);
1250 c_write(stuff, strlen(stuff));
1254 send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END);
1256 char userlog[20+sizeof(username)];
1257 sprintf(userlog, "Sent username \"%s\"", username);
1264 tried_publickey = 0;
1266 while (pktin.type == SSH1_SMSG_FAILURE) {
1267 static char password[100];
1268 static char prompt[200];
1271 static int pwpkt_type;
1273 * Show password prompt, having first obtained it via a TIS
1274 * or CryptoCard exchange if we're doing TIS or CryptoCard
1277 pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
1278 if (agent_exists()) {
1280 * Attempt RSA authentication using Pageant.
1282 static unsigned char request[5], *response, *p;
1283 static int responselen;
1284 static int i, nkeys;
1285 static int authed = FALSE;
1288 logevent("Pageant is running. Requesting keys.");
1290 /* Request the keys held by the agent. */
1291 PUT_32BIT(request, 1);
1292 request[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES;
1293 agent_query(request, 5, &r, &responselen);
1294 response = (unsigned char *)r;
1297 nkeys = GET_32BIT(p); p += 4;
1298 { char buf[64]; sprintf(buf, "Pageant has %d keys", nkeys);
1300 for (i = 0; i < nkeys; i++) {
1301 static struct RSAKey key;
1302 static Bignum challenge;
1303 static char *commentp;
1304 static int commentlen;
1306 { char buf[64]; sprintf(buf, "Trying Pageant key #%d", i);
1309 p += ssh1_read_bignum(p, &key.exponent);
1310 p += ssh1_read_bignum(p, &key.modulus);
1311 commentlen = GET_32BIT(p); p += 4;
1312 commentp = p; p += commentlen;
1313 send_packet(SSH1_CMSG_AUTH_RSA,
1314 PKT_BIGNUM, key.modulus, PKT_END);
1316 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
1317 logevent("Key refused");
1320 logevent("Received RSA challenge");
1321 ssh1_read_bignum(pktin.body, &challenge);
1323 char *agentreq, *q, *ret;
1325 len = 1 + 4; /* message type, bit count */
1326 len += ssh1_bignum_length(key.exponent);
1327 len += ssh1_bignum_length(key.modulus);
1328 len += ssh1_bignum_length(challenge);
1329 len += 16; /* session id */
1330 len += 4; /* response format */
1331 agentreq = malloc(4 + len);
1332 PUT_32BIT(agentreq, len);
1334 *q++ = SSH_AGENTC_RSA_CHALLENGE;
1335 PUT_32BIT(q, ssh1_bignum_bitcount(key.modulus));
1337 q += ssh1_write_bignum(q, key.exponent);
1338 q += ssh1_write_bignum(q, key.modulus);
1339 q += ssh1_write_bignum(q, challenge);
1340 memcpy(q, session_id, 16); q += 16;
1341 PUT_32BIT(q, 1); /* response format */
1342 agent_query(agentreq, len+4, &ret, &retlen);
1345 if (ret[4] == SSH_AGENT_RSA_RESPONSE) {
1346 logevent("Sending Pageant's response");
1347 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
1348 PKT_DATA, ret+5, 16, PKT_END);
1351 if (pktin.type == SSH1_SMSG_SUCCESS) {
1352 logevent("Pageant's response accepted");
1353 if (flags & FLAG_VERBOSE) {
1354 c_write("Authenticated using RSA key \"",
1356 c_write(commentp, commentlen);
1357 c_write("\" from agent\r\n", 14);
1361 logevent("Pageant's response not accepted");
1363 logevent("Pageant failed to answer challenge");
1367 logevent("No reply received from Pageant");
1370 freebn(key.exponent);
1371 freebn(key.modulus);
1380 if (*cfg.keyfile && !tried_publickey)
1381 pwpkt_type = SSH1_CMSG_AUTH_RSA;
1383 if (pktin.type == SSH1_SMSG_FAILURE &&
1385 (supported_auths_mask & (1<<SSH1_AUTH_TIS))) {
1386 pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
1387 logevent("Requested TIS authentication");
1388 send_packet(SSH1_CMSG_AUTH_TIS, PKT_END);
1390 if (pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
1391 logevent("TIS authentication declined");
1392 if (flags & FLAG_INTERACTIVE)
1393 c_write("TIS authentication refused.\r\n", 29);
1395 int challengelen = ((pktin.body[0] << 24) |
1396 (pktin.body[1] << 16) |
1397 (pktin.body[2] << 8) |
1399 logevent("Received TIS challenge");
1400 if (challengelen > sizeof(prompt)-1)
1401 challengelen = sizeof(prompt)-1; /* prevent overrun */
1402 memcpy(prompt, pktin.body+4, challengelen);
1403 prompt[challengelen] = '\0';
1406 if (pktin.type == SSH1_SMSG_FAILURE &&
1408 (supported_auths_mask & (1<<SSH1_AUTH_CCARD))) {
1409 pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
1410 logevent("Requested CryptoCard authentication");
1411 send_packet(SSH1_CMSG_AUTH_CCARD, PKT_END);
1413 if (pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
1414 logevent("CryptoCard authentication declined");
1415 c_write("CryptoCard authentication refused.\r\n", 29);
1417 int challengelen = ((pktin.body[0] << 24) |
1418 (pktin.body[1] << 16) |
1419 (pktin.body[2] << 8) |
1421 logevent("Received CryptoCard challenge");
1422 if (challengelen > sizeof(prompt)-1)
1423 challengelen = sizeof(prompt)-1; /* prevent overrun */
1424 memcpy(prompt, pktin.body+4, challengelen);
1425 strncpy(prompt + challengelen, "\r\nResponse : ",
1426 sizeof(prompt)-challengelen);
1427 prompt[sizeof(prompt)-1] = '\0';
1430 if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
1431 sprintf(prompt, "%.90s@%.90s's password: ",
1432 username, savedhost);
1434 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
1435 char *comment = NULL;
1436 if (flags & FLAG_VERBOSE)
1437 c_write("Trying public key authentication.\r\n", 35);
1438 if (!rsakey_encrypted(cfg.keyfile, &comment)) {
1439 if (flags & FLAG_VERBOSE)
1440 c_write("No passphrase required.\r\n", 25);
1443 sprintf(prompt, "Passphrase for key \"%.100s\": ", comment);
1447 if (ssh_get_password) {
1448 if (!ssh_get_password(prompt, password, sizeof(password))) {
1450 * get_password failed to get a password (for
1451 * example because one was supplied on the command
1452 * line which has already failed to work).
1455 logevent("No more passwords to try");
1456 ssh_state = SSH_STATE_CLOSED;
1460 c_write(prompt, strlen(prompt));
1464 crWaitUntil(!ispkt);
1465 while (inlen--) switch (c = *in++) {
1482 if (((c >= ' ' && c <= '~') ||
1483 ((unsigned char)c >= 160)) && pos < sizeof(password))
1484 password[pos++] = c;
1492 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
1494 * Try public key authentication with the specified
1497 static struct RSAKey pubkey;
1498 static Bignum challenge, response;
1500 static unsigned char buffer[32];
1502 tried_publickey = 1;
1503 i = loadrsakey(cfg.keyfile, &pubkey, NULL, password);
1505 c_write("Couldn't load public key from ", 30);
1506 c_write(cfg.keyfile, strlen(cfg.keyfile));
1507 c_write(".\r\n", 3);
1508 continue; /* go and try password */
1511 c_write("Wrong passphrase.\r\n", 19);
1512 tried_publickey = 0;
1513 continue; /* try again */
1517 * Send a public key attempt.
1519 send_packet(SSH1_CMSG_AUTH_RSA,
1520 PKT_BIGNUM, pubkey.modulus, PKT_END);
1523 if (pktin.type == SSH1_SMSG_FAILURE) {
1524 c_write("Server refused our public key.\r\n", 32);
1525 continue; /* go and try password */
1527 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
1528 bombout(("Bizarre response to offer of public key"));
1531 ssh1_read_bignum(pktin.body, &challenge);
1532 response = rsadecrypt(challenge, &pubkey);
1533 freebn(pubkey.private_exponent); /* burn the evidence */
1535 for (i = 0; i < 32; i += 2) {
1536 buffer[i] = response[16-i/2] >> 8;
1537 buffer[i+1] = response[16-i/2] & 0xFF;
1541 MD5Update(&md5c, buffer, 32);
1542 MD5Update(&md5c, session_id, 16);
1543 MD5Final(buffer, &md5c);
1545 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
1546 PKT_DATA, buffer, 16, PKT_END);
1549 if (pktin.type == SSH1_SMSG_FAILURE) {
1550 if (flags & FLAG_VERBOSE)
1551 c_write("Failed to authenticate with our public key.\r\n",
1553 continue; /* go and try password */
1554 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
1555 bombout(("Bizarre response to RSA authentication response"));
1559 break; /* we're through! */
1561 send_packet(pwpkt_type, PKT_STR, password, PKT_END);
1563 logevent("Sent password");
1564 memset(password, 0, strlen(password));
1566 if (pktin.type == SSH1_SMSG_FAILURE) {
1567 if (flags & FLAG_VERBOSE)
1568 c_write("Access denied\r\n", 15);
1569 logevent("Authentication refused");
1570 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
1571 logevent("Received disconnect request");
1572 ssh_state = SSH_STATE_CLOSED;
1574 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
1575 bombout(("Strange packet received, type %d", pktin.type));
1580 logevent("Authentication successful");
1585 static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) {
1590 while (!do_ssh1_login(in, inlen, ispkt)) {
1593 if (ssh_state == SSH_STATE_CLOSED)
1596 if (cfg.agentfwd && agent_exists()) {
1597 logevent("Requesting agent forwarding");
1598 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
1599 do { crReturnV; } while (!ispkt);
1600 if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
1601 bombout(("Protocol confusion"));
1603 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1604 logevent("Agent forwarding refused");
1606 logevent("Agent forwarding enabled");
1610 send_packet(SSH1_CMSG_REQUEST_PTY,
1611 PKT_STR, cfg.termtype,
1612 PKT_INT, rows, PKT_INT, cols,
1613 PKT_INT, 0, PKT_INT, 0,
1616 ssh_state = SSH_STATE_INTERMED;
1617 do { crReturnV; } while (!ispkt);
1618 if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
1619 bombout(("Protocol confusion"));
1621 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1622 c_write("Server refused to allocate pty\r\n", 32);
1624 logevent("Allocated pty");
1627 if (*cfg.remote_cmd)
1628 send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cfg.remote_cmd, PKT_END);
1630 send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END);
1631 logevent("Started session");
1633 ssh_state = SSH_STATE_SESSION;
1638 ssh_channels = newtree234(ssh_channelcmp);
1643 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
1644 pktin.type == SSH1_SMSG_STDERR_DATA) {
1645 long len = GET_32BIT(pktin.body);
1646 from_backend(pktin.type == SSH1_SMSG_STDERR_DATA,
1648 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
1649 ssh_state = SSH_STATE_CLOSED;
1650 logevent("Received disconnect request");
1652 } else if (pktin.type == SSH1_SMSG_AGENT_OPEN) {
1653 /* Remote side is trying to open a channel to talk to our
1654 * agent. Give them back a local channel number. */
1656 struct ssh_channel *c;
1658 for (c = first234(ssh_channels, &e); c; c = next234(&e)) {
1660 break; /* found a free number */
1663 c = malloc(sizeof(struct ssh_channel));
1664 c->remoteid = GET_32BIT(pktin.body);
1667 c->type = SSH1_SMSG_AGENT_OPEN; /* identify channel type */
1668 c->u.a.lensofar = 0;
1669 add234(ssh_channels, c);
1670 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
1671 PKT_INT, c->remoteid, PKT_INT, c->localid,
1673 } else if (pktin.type == SSH1_MSG_CHANNEL_CLOSE ||
1674 pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
1675 /* Remote side closes a channel. */
1676 unsigned i = GET_32BIT(pktin.body);
1677 struct ssh_channel *c;
1678 c = find234(ssh_channels, &i, ssh_channelfind);
1681 closetype = (pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
1682 send_packet(pktin.type, PKT_INT, c->remoteid, PKT_END);
1683 c->closes |= closetype;
1684 if (c->closes == 3) {
1685 del234(ssh_channels, c);
1689 } else if (pktin.type == SSH1_MSG_CHANNEL_DATA) {
1690 /* Data sent down one of our channels. */
1691 int i = GET_32BIT(pktin.body);
1692 int len = GET_32BIT(pktin.body+4);
1693 unsigned char *p = pktin.body+8;
1694 struct ssh_channel *c;
1695 c = find234(ssh_channels, &i, ssh_channelfind);
1698 case SSH1_SMSG_AGENT_OPEN:
1699 /* Data for an agent message. Buffer it. */
1701 if (c->u.a.lensofar < 4) {
1702 int l = min(4 - c->u.a.lensofar, len);
1703 memcpy(c->u.a.msglen + c->u.a.lensofar, p, l);
1704 p += l; len -= l; c->u.a.lensofar += l;
1706 if (c->u.a.lensofar == 4) {
1707 c->u.a.totallen = 4 + GET_32BIT(c->u.a.msglen);
1708 c->u.a.message = malloc(c->u.a.totallen);
1709 memcpy(c->u.a.message, c->u.a.msglen, 4);
1711 if (c->u.a.lensofar >= 4 && len > 0) {
1712 int l = min(c->u.a.totallen - c->u.a.lensofar, len);
1713 memcpy(c->u.a.message + c->u.a.lensofar, p, l);
1714 p += l; len -= l; c->u.a.lensofar += l;
1716 if (c->u.a.lensofar == c->u.a.totallen) {
1717 void *reply, *sentreply;
1719 agent_query(c->u.a.message, c->u.a.totallen,
1724 /* Fake SSH_AGENT_FAILURE. */
1725 sentreply = "\0\0\0\1\5";
1728 send_packet(SSH1_MSG_CHANNEL_DATA,
1729 PKT_INT, c->remoteid,
1731 PKT_DATA, sentreply, replylen,
1735 free(c->u.a.message);
1736 c->u.a.lensofar = 0;
1742 } else if (pktin.type == SSH1_SMSG_SUCCESS) {
1743 /* may be from EXEC_SHELL on some servers */
1744 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1745 /* may be from EXEC_SHELL on some servers
1746 * if no pty is available or in other odd cases. Ignore */
1747 } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) {
1748 send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
1750 bombout(("Strange packet received: type %d", pktin.type));
1755 int len = min(inlen, 512);
1756 send_packet(SSH1_CMSG_STDIN_DATA,
1757 PKT_INT, len, PKT_DATA, in, len, PKT_END);
1768 * Utility routine for decoding comma-separated strings in KEXINIT.
1770 static int in_commasep_string(char *needle, char *haystack, int haylen) {
1771 int needlen = strlen(needle);
1774 * Is it at the start of the string?
1776 if (haylen >= needlen && /* haystack is long enough */
1777 !memcmp(needle, haystack, needlen) && /* initial match */
1778 (haylen == needlen || haystack[needlen] == ',')
1779 /* either , or EOS follows */
1783 * If not, search for the next comma and resume after that.
1784 * If no comma found, terminate.
1786 while (haylen > 0 && *haystack != ',')
1787 haylen--, haystack++;
1790 haylen--, haystack++; /* skip over comma itself */
1795 * SSH2 key creation method.
1797 static void ssh2_mkkey(Bignum K, char *H, char chr, char *keyspace) {
1799 /* First 20 bytes. */
1802 SHA_Bytes(&s, H, 20);
1803 SHA_Bytes(&s, &chr, 1);
1804 SHA_Bytes(&s, H, 20);
1805 SHA_Final(&s, keyspace);
1806 /* Next 20 bytes. */
1809 SHA_Bytes(&s, H, 20);
1810 SHA_Bytes(&s, keyspace, 20);
1811 SHA_Final(&s, keyspace+20);
1815 * Handle the SSH2 transport layer.
1817 static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt)
1821 static Bignum e, f, K;
1822 static const struct ssh_mac **maclist;
1824 static const struct ssh_cipher *cscipher_tobe = NULL;
1825 static const struct ssh_cipher *sccipher_tobe = NULL;
1826 static const struct ssh_mac *csmac_tobe = NULL;
1827 static const struct ssh_mac *scmac_tobe = NULL;
1828 static const struct ssh_compress *cscomp_tobe = NULL;
1829 static const struct ssh_compress *sccomp_tobe = NULL;
1830 static char *hostkeydata, *sigdata, *keystr, *fingerprint;
1831 static int hostkeylen, siglen;
1832 static unsigned char exchange_hash[20];
1833 static unsigned char keyspace[40];
1834 static const struct ssh_cipher *preferred_cipher;
1840 * Set up the preferred cipher.
1842 if (cfg.cipher == CIPHER_BLOWFISH) {
1843 preferred_cipher = &ssh_blowfish_ssh2;
1844 } else if (cfg.cipher == CIPHER_DES) {
1845 logevent("Single DES not supported in SSH2; using 3DES");
1846 preferred_cipher = &ssh_3des_ssh2;
1847 } else if (cfg.cipher == CIPHER_3DES) {
1848 preferred_cipher = &ssh_3des_ssh2;
1850 /* Shouldn't happen, but we do want to initialise to _something_. */
1851 preferred_cipher = &ssh_3des_ssh2;
1855 * Be prepared to work around the buggy MAC problem.
1858 maclist = buggymacs, nmacs = lenof(buggymacs);
1860 maclist = macs, nmacs = lenof(macs);
1864 * Construct and send our key exchange packet.
1866 ssh2_pkt_init(SSH2_MSG_KEXINIT);
1867 for (i = 0; i < 16; i++)
1868 ssh2_pkt_addbyte((unsigned char)random_byte());
1869 /* List key exchange algorithms. */
1870 ssh2_pkt_addstring_start();
1871 for (i = 0; i < lenof(kex_algs); i++) {
1872 ssh2_pkt_addstring_str(kex_algs[i]->name);
1873 if (i < lenof(kex_algs)-1)
1874 ssh2_pkt_addstring_str(",");
1876 /* List server host key algorithms. */
1877 ssh2_pkt_addstring_start();
1878 for (i = 0; i < lenof(hostkey_algs); i++) {
1879 ssh2_pkt_addstring_str(hostkey_algs[i]->name);
1880 if (i < lenof(hostkey_algs)-1)
1881 ssh2_pkt_addstring_str(",");
1883 /* List client->server encryption algorithms. */
1884 ssh2_pkt_addstring_start();
1885 for (i = 0; i < lenof(ciphers)+1; i++) {
1886 const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
1887 ssh2_pkt_addstring_str(c->name);
1888 if (i < lenof(ciphers))
1889 ssh2_pkt_addstring_str(",");
1891 /* List server->client encryption algorithms. */
1892 ssh2_pkt_addstring_start();
1893 for (i = 0; i < lenof(ciphers)+1; i++) {
1894 const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
1895 ssh2_pkt_addstring_str(c->name);
1896 if (i < lenof(ciphers))
1897 ssh2_pkt_addstring_str(",");
1899 /* List client->server MAC algorithms. */
1900 ssh2_pkt_addstring_start();
1901 for (i = 0; i < nmacs; i++) {
1902 ssh2_pkt_addstring_str(maclist[i]->name);
1904 ssh2_pkt_addstring_str(",");
1906 /* List server->client MAC algorithms. */
1907 ssh2_pkt_addstring_start();
1908 for (i = 0; i < nmacs; i++) {
1909 ssh2_pkt_addstring_str(maclist[i]->name);
1911 ssh2_pkt_addstring_str(",");
1913 /* List client->server compression algorithms. */
1914 ssh2_pkt_addstring_start();
1915 for (i = 0; i < lenof(compressions); i++) {
1916 ssh2_pkt_addstring_str(compressions[i]->name);
1917 if (i < lenof(compressions)-1)
1918 ssh2_pkt_addstring_str(",");
1920 /* List server->client compression algorithms. */
1921 ssh2_pkt_addstring_start();
1922 for (i = 0; i < lenof(compressions); i++) {
1923 ssh2_pkt_addstring_str(compressions[i]->name);
1924 if (i < lenof(compressions)-1)
1925 ssh2_pkt_addstring_str(",");
1927 /* List client->server languages. Empty list. */
1928 ssh2_pkt_addstring_start();
1929 /* List server->client languages. Empty list. */
1930 ssh2_pkt_addstring_start();
1931 /* First KEX packet does _not_ follow, because we're not that brave. */
1932 ssh2_pkt_addbool(FALSE);
1934 ssh2_pkt_adduint32(0);
1935 sha_string(&exhash, pktout.data+5, pktout.length-5);
1938 if (!ispkt) crWaitUntil(ispkt);
1939 sha_string(&exhash, pktin.data+5, pktin.length-5);
1942 * Now examine the other side's KEXINIT to see what we're up
1945 if (pktin.type != SSH2_MSG_KEXINIT) {
1946 bombout(("expected key exchange packet from server"));
1949 kex = NULL; hostkey = NULL; cscipher_tobe = NULL; sccipher_tobe = NULL;
1950 csmac_tobe = NULL; scmac_tobe = NULL; cscomp_tobe = NULL; sccomp_tobe = NULL;
1951 pktin.savedpos += 16; /* skip garbage cookie */
1952 ssh2_pkt_getstring(&str, &len); /* key exchange algorithms */
1953 for (i = 0; i < lenof(kex_algs); i++) {
1954 if (in_commasep_string(kex_algs[i]->name, str, len)) {
1959 ssh2_pkt_getstring(&str, &len); /* host key algorithms */
1960 for (i = 0; i < lenof(hostkey_algs); i++) {
1961 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
1962 hostkey = hostkey_algs[i];
1966 ssh2_pkt_getstring(&str, &len); /* client->server cipher */
1967 for (i = 0; i < lenof(ciphers)+1; i++) {
1968 const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
1969 if (in_commasep_string(c->name, str, len)) {
1974 ssh2_pkt_getstring(&str, &len); /* server->client cipher */
1975 for (i = 0; i < lenof(ciphers)+1; i++) {
1976 const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
1977 if (in_commasep_string(c->name, str, len)) {
1982 ssh2_pkt_getstring(&str, &len); /* client->server mac */
1983 for (i = 0; i < nmacs; i++) {
1984 if (in_commasep_string(maclist[i]->name, str, len)) {
1985 csmac_tobe = maclist[i];
1989 ssh2_pkt_getstring(&str, &len); /* server->client mac */
1990 for (i = 0; i < nmacs; i++) {
1991 if (in_commasep_string(maclist[i]->name, str, len)) {
1992 scmac_tobe = maclist[i];
1996 ssh2_pkt_getstring(&str, &len); /* client->server compression */
1997 for (i = 0; i < lenof(compressions); i++) {
1998 if (in_commasep_string(compressions[i]->name, str, len)) {
1999 cscomp_tobe = compressions[i];
2003 ssh2_pkt_getstring(&str, &len); /* server->client compression */
2004 for (i = 0; i < lenof(compressions); i++) {
2005 if (in_commasep_string(compressions[i]->name, str, len)) {
2006 sccomp_tobe = compressions[i];
2012 * Currently we only support Diffie-Hellman and DSS, so let's
2013 * bomb out if those aren't selected.
2015 if (kex != &ssh_diffiehellman || hostkey != &ssh_dss) {
2016 bombout(("internal fault: chaos in SSH 2 transport layer"));
2021 * Now we begin the fun. Generate and send e for Diffie-Hellman.
2024 ssh2_pkt_init(SSH2_MSG_KEXDH_INIT);
2029 if (pktin.type != SSH2_MSG_KEXDH_REPLY) {
2030 bombout(("expected key exchange packet from server"));
2033 ssh2_pkt_getstring(&hostkeydata, &hostkeylen);
2034 f = ssh2_pkt_getmp();
2035 ssh2_pkt_getstring(&sigdata, &siglen);
2039 sha_string(&exhash, hostkeydata, hostkeylen);
2040 sha_mpint(&exhash, e);
2041 sha_mpint(&exhash, f);
2042 sha_mpint(&exhash, K);
2043 SHA_Final(&exhash, exchange_hash);
2046 debug(("Exchange hash is:\r\n"));
2047 for (i = 0; i < 20; i++)
2048 debug((" %02x", exchange_hash[i]));
2052 hostkey->setkey(hostkeydata, hostkeylen);
2053 if (!hostkey->verifysig(sigdata, siglen, exchange_hash, 20)) {
2054 bombout(("Server failed host key check"));
2059 * Expect SSH2_MSG_NEWKEYS from server.
2062 if (pktin.type != SSH2_MSG_NEWKEYS) {
2063 bombout(("expected new-keys packet from server"));
2068 * Authenticate remote host: verify host key. (We've already
2069 * checked the signature of the exchange hash.)
2071 keystr = hostkey->fmtkey();
2072 fingerprint = hostkey->fingerprint();
2073 verify_ssh_host_key(savedhost, savedport, hostkey->keytype,
2074 keystr, fingerprint);
2075 logevent("Host key fingerprint is:");
2076 logevent(fingerprint);
2081 * Send SSH2_MSG_NEWKEYS.
2083 ssh2_pkt_init(SSH2_MSG_NEWKEYS);
2087 * Create and initialise session keys.
2089 cscipher = cscipher_tobe;
2090 sccipher = sccipher_tobe;
2093 cscomp = cscomp_tobe;
2094 sccomp = sccomp_tobe;
2096 * Set IVs after keys.
2098 ssh2_mkkey(K, exchange_hash, 'C', keyspace); cscipher->setcskey(keyspace);
2099 ssh2_mkkey(K, exchange_hash, 'D', keyspace); cscipher->setsckey(keyspace);
2100 ssh2_mkkey(K, exchange_hash, 'A', keyspace); cscipher->setcsiv(keyspace);
2101 ssh2_mkkey(K, exchange_hash, 'B', keyspace); sccipher->setsciv(keyspace);
2102 ssh2_mkkey(K, exchange_hash, 'E', keyspace); csmac->setcskey(keyspace);
2103 ssh2_mkkey(K, exchange_hash, 'F', keyspace); scmac->setsckey(keyspace);
2106 * Now we're encrypting. Begin returning 1 to the protocol main
2107 * function so that other things can run on top of the
2108 * transport. If we ever see a KEXINIT, we must go back to the
2113 } while (!(ispkt && pktin.type == SSH2_MSG_KEXINIT));
2114 goto begin_key_exchange;
2120 * Handle the SSH2 userauth and connection layers.
2122 static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
2124 static unsigned long remote_winsize;
2125 static unsigned long remote_maxpkt;
2130 * Request userauth protocol, and await a response to it.
2132 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
2133 ssh2_pkt_addstring("ssh-userauth");
2135 crWaitUntilV(ispkt);
2136 if (pktin.type != SSH2_MSG_SERVICE_ACCEPT) {
2137 bombout(("Server refused user authentication protocol"));
2142 * FIXME: currently we support only password authentication.
2143 * (This places us technically in violation of the SSH2 spec.
2144 * We must fix this.)
2148 * Get a username and a password.
2150 static char username[100];
2151 static char password[100];
2155 if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
2156 c_write("login as: ", 10);
2159 crWaitUntilV(!ispkt);
2160 while (inlen--) switch (c = *in++) {
2167 c_write("\b \b", 3);
2173 c_write("\b \b", 3);
2182 if (((c >= ' ' && c <= '~') ||
2183 ((unsigned char)c >= 160)) && pos < 40) {
2184 username[pos++] = c;
2191 username[strcspn(username, "\n\r")] = '\0';
2194 strncpy(username, cfg.username, 99);
2195 username[99] = '\0';
2196 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
2197 sprintf(stuff, "Using username \"%s\".\r\n", username);
2198 c_write(stuff, strlen(stuff));
2202 if (ssh_get_password) {
2204 sprintf(prompt, "%.90s@%.90s's password: ", username, savedhost);
2205 if (!ssh_get_password(prompt, password, sizeof(password))) {
2207 * get_password failed to get a password (for
2208 * example because one was supplied on the command
2209 * line which has already failed to work).
2212 logevent("No more passwords to try");
2213 ssh_state = SSH_STATE_CLOSED;
2217 c_write("password: ", 10);
2222 crWaitUntilV(!ispkt);
2223 while (inlen--) switch (c = *in++) {
2240 if (((c >= ' ' && c <= '~') ||
2241 ((unsigned char)c >= 160)) && pos < 40)
2242 password[pos++] = c;
2249 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
2250 ssh2_pkt_addstring(username);
2251 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2252 ssh2_pkt_addstring("password");
2253 ssh2_pkt_addbool(FALSE);
2254 ssh2_pkt_addstring(password);
2257 crWaitUntilV(ispkt);
2258 if (pktin.type != SSH2_MSG_USERAUTH_SUCCESS) {
2259 c_write("Access denied\r\n", 15);
2260 logevent("Authentication refused");
2266 * Now we're authenticated for the connection protocol. The
2267 * connection protocol will automatically have started at this
2268 * point; there's no need to send SERVICE_REQUEST.
2272 * So now create a channel with a session in it.
2274 mainchan = malloc(sizeof(struct ssh_channel));
2275 mainchan->localid = 100; /* as good as any */
2276 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
2277 ssh2_pkt_addstring("session");
2278 ssh2_pkt_adduint32(mainchan->localid);
2279 ssh2_pkt_adduint32(0x8000UL); /* our window size */
2280 ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
2282 crWaitUntilV(ispkt);
2283 if (pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
2284 bombout(("Server refused to open a session"));
2286 /* FIXME: error data comes back in FAILURE packet */
2288 if (ssh2_pkt_getuint32() != mainchan->localid) {
2289 bombout(("Server's channel confirmation cited wrong channel"));
2292 mainchan->remoteid = ssh2_pkt_getuint32();
2293 mainchan->u.v2.remwindow = ssh2_pkt_getuint32();
2294 mainchan->u.v2.remmaxpkt = ssh2_pkt_getuint32();
2295 mainchan->u.v2.outbuffer = NULL;
2296 mainchan->u.v2.outbuflen = mainchan->u.v2.outbufsize = 0;
2297 logevent("Opened channel for session");
2300 * Now allocate a pty for the session.
2303 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
2304 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
2305 ssh2_pkt_addstring("pty-req");
2306 ssh2_pkt_addbool(1); /* want reply */
2307 ssh2_pkt_addstring(cfg.termtype);
2308 ssh2_pkt_adduint32(cols);
2309 ssh2_pkt_adduint32(rows);
2310 ssh2_pkt_adduint32(0); /* pixel width */
2311 ssh2_pkt_adduint32(0); /* pixel height */
2312 ssh2_pkt_addstring_start();
2313 ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
2315 ssh_state = SSH_STATE_INTERMED;
2318 crWaitUntilV(ispkt);
2319 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2320 /* FIXME: be able to handle other channels here */
2321 if (ssh2_pkt_getuint32() != mainchan->localid)
2322 continue; /* wrong channel */
2323 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2325 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2327 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
2328 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
2329 bombout(("Server got confused by pty request"));
2332 c_write("Server refused to allocate pty\r\n", 32);
2334 logevent("Allocated pty");
2339 * Start a shell or a remote command.
2341 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
2342 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
2343 if (*cfg.remote_cmd) {
2344 ssh2_pkt_addstring("exec");
2345 ssh2_pkt_addbool(1); /* want reply */
2346 ssh2_pkt_addstring(cfg.remote_cmd);
2348 ssh2_pkt_addstring("shell");
2349 ssh2_pkt_addbool(1); /* want reply */
2353 crWaitUntilV(ispkt);
2354 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2355 /* FIXME: be able to handle other channels here */
2356 if (ssh2_pkt_getuint32() != mainchan->localid)
2357 continue; /* wrong channel */
2358 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2360 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2361 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
2362 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
2363 bombout(("Server got confused by shell/command request"));
2366 bombout(("Server refused to start a shell/command"));
2369 logevent("Started a shell/command");
2372 ssh_state = SSH_STATE_SESSION;
2382 static int try_send;
2386 if (pktin.type == SSH2_MSG_CHANNEL_DATA ||
2387 pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
2390 /* FIXME: be able to handle other channels here */
2391 if (ssh2_pkt_getuint32() != mainchan->localid)
2392 continue; /* wrong channel */
2393 if (pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
2394 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR)
2395 continue; /* extended but not stderr */
2396 ssh2_pkt_getstring(&data, &length);
2398 from_backend(pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA,
2401 * Enlarge the window again at the remote side,
2402 * just in case it ever runs down and they fail
2403 * to send us any more data.
2405 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2406 ssh2_pkt_adduint32(mainchan->remoteid);
2407 ssh2_pkt_adduint32(length);
2410 } else if (pktin.type == SSH2_MSG_DISCONNECT) {
2411 ssh_state = SSH_STATE_CLOSED;
2412 logevent("Received disconnect message");
2414 } else if (pktin.type == SSH2_MSG_CHANNEL_REQUEST) {
2415 continue; /* exit status et al; ignore (FIXME?) */
2416 } else if (pktin.type == SSH2_MSG_CHANNEL_EOF) {
2417 continue; /* remote sends EOF; ignore */
2418 } else if (pktin.type == SSH2_MSG_CHANNEL_CLOSE) {
2419 /* FIXME: be able to handle other channels here */
2420 if (ssh2_pkt_getuint32() != mainchan->localid)
2421 continue; /* wrong channel */
2422 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
2423 ssh2_pkt_adduint32(mainchan->remoteid);
2425 /* FIXME: mark the channel as closed */
2426 if (1 /* FIXME: "all channels are closed" */) {
2427 logevent("All channels closed. Disconnecting");
2428 ssh2_pkt_init(SSH2_MSG_DISCONNECT);
2430 ssh_state = SSH_STATE_CLOSED;
2433 continue; /* remote sends close; ignore (FIXME) */
2434 } else if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2435 /* FIXME: be able to handle other channels here */
2436 if (ssh2_pkt_getuint32() != mainchan->localid)
2437 continue; /* wrong channel */
2438 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2441 bombout(("Strange packet received: type %d", pktin.type));
2446 * We have spare data. Add it to the channel buffer.
2448 if (mainchan->u.v2.outbufsize <
2449 mainchan->u.v2.outbuflen + inlen) {
2450 mainchan->u.v2.outbufsize =
2451 mainchan->u.v2.outbuflen + inlen + 1024;
2452 mainchan->u.v2.outbuffer = srealloc(mainchan->u.v2.outbuffer,
2453 mainchan->u.v2.outbufsize);
2455 memcpy(mainchan->u.v2.outbuffer + mainchan->u.v2.outbuflen,
2457 mainchan->u.v2.outbuflen += inlen;
2462 * Try to send data on the channel if we can. (FIXME:
2463 * on _all_ channels.)
2465 while (mainchan->u.v2.remwindow > 0 &&
2466 mainchan->u.v2.outbuflen > 0) {
2467 unsigned len = mainchan->u.v2.remwindow;
2468 if (len > mainchan->u.v2.outbuflen)
2469 len = mainchan->u.v2.outbuflen;
2470 if (len > mainchan->u.v2.remmaxpkt)
2471 len = mainchan->u.v2.remmaxpkt;
2472 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
2473 ssh2_pkt_adduint32(mainchan->remoteid);
2474 ssh2_pkt_addstring_start();
2475 ssh2_pkt_addstring_data(mainchan->u.v2.outbuffer, len);
2477 mainchan->u.v2.outbuflen -= len;
2478 memmove(mainchan->u.v2.outbuffer, mainchan->u.v2.outbuffer+len,
2479 mainchan->u.v2.outbuflen);
2480 mainchan->u.v2.remwindow -= len;
2489 * Handle the top-level SSH2 protocol.
2491 static void ssh2_protocol(unsigned char *in, int inlen, int ispkt)
2493 if (do_ssh2_transport(in, inlen, ispkt) == 0)
2495 do_ssh2_authconn(in, inlen, ispkt);
2499 * Called to set up the connection.
2501 * Returns an error message, or NULL on success.
2503 static char *ssh_init (char *host, int port, char **realhost) {
2507 if(crypto_startup() == 0)
2508 return "Microsoft high encryption pack not installed!";
2513 p = connect_to_host(host, port, realhost);
2521 * Called to send data down the Telnet connection.
2523 static void ssh_send (char *buf, int len) {
2527 ssh_protocol(buf, len, 0);
2531 * Called to set the size of the window from SSH's POV.
2533 static void ssh_size(void) {
2534 switch (ssh_state) {
2535 case SSH_STATE_BEFORE_SIZE:
2536 case SSH_STATE_CLOSED:
2537 break; /* do nothing */
2538 case SSH_STATE_INTERMED:
2539 size_needed = TRUE; /* buffer for later */
2541 case SSH_STATE_SESSION:
2543 if (ssh_version == 1) {
2544 send_packet(SSH1_CMSG_WINDOW_SIZE,
2545 PKT_INT, rows, PKT_INT, cols,
2546 PKT_INT, 0, PKT_INT, 0, PKT_END);
2548 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
2549 ssh2_pkt_adduint32(mainchan->remoteid);
2550 ssh2_pkt_addstring("window-change");
2551 ssh2_pkt_addbool(0);
2552 ssh2_pkt_adduint32(cols);
2553 ssh2_pkt_adduint32(rows);
2554 ssh2_pkt_adduint32(0);
2555 ssh2_pkt_adduint32(0);
2563 * Send Telnet special codes. TS_EOF is useful for `plink', so you
2564 * can send an EOF and collect resulting output (e.g. `plink
2567 static void ssh_special (Telnet_Special code) {
2568 if (code == TS_EOF) {
2569 if (ssh_version == 1) {
2570 send_packet(SSH1_CMSG_EOF, PKT_END);
2572 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
2573 ssh2_pkt_adduint32(mainchan->remoteid);
2576 logevent("Sent EOF message");
2577 } else if (code == TS_PING) {
2578 if (ssh_version == 1) {
2579 send_packet(SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
2581 ssh2_pkt_init(SSH2_MSG_IGNORE);
2582 ssh2_pkt_addstring_start();
2590 static Socket ssh_socket(void) { return s; }
2592 static int ssh_sendok(void) { return ssh_send_ok; }
2594 Backend ssh_backend = {