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]);
852 while (b[0] > 1 && b[b[0]] == 0) b[0]--;
856 static int do_ssh_init(unsigned char c) {
858 static char version[10];
859 static char vstring[80];
860 static char vlog[sizeof(vstring)+20];
865 /* Search for the string "SSH-" in the input. */
868 static const int transS[] = { 1, 2, 2, 1 };
869 static const int transH[] = { 0, 0, 3, 0 };
870 static const int transminus[] = { 0, 0, 0, -1 };
871 if (c == 'S') i = transS[i];
872 else if (c == 'H') i = transH[i];
873 else if (c == '-') i = transminus[i];
877 crReturn(1); /* get another character */
880 strcpy(vstring, "SSH-");
884 crReturn(1); /* get another char */
885 if (vsp < vstring+sizeof(vstring)-1)
891 } else if (i < sizeof(version)-1)
898 rdpkt2_state.incoming_sequence = 0;
901 sprintf(vlog, "Server version: %s", vstring);
902 vlog[strcspn(vlog, "\r\n")] = '\0';
906 * Server version "1.99" means we can choose whether we use v1
907 * or v2 protocol. Choice is based on cfg.sshprot.
909 if (ssh_versioncmp(version, cfg.sshprot == 1 ? "2.0" : "1.99") >= 0) {
911 * This is a v2 server. Begin v2 protocol.
913 char *verstring = "SSH-2.0-PuTTY";
916 * Hash our version string and their version string.
918 sha_string(&exhash, verstring, strlen(verstring));
919 sha_string(&exhash, vstring, strcspn(vstring, "\r\n"));
920 sprintf(vstring, "%s\n", verstring);
921 sprintf(vlog, "We claim version: %s", verstring);
923 logevent("Using SSH protocol version 2");
924 sk_write(s, vstring, strlen(vstring));
925 ssh_protocol = ssh2_protocol;
927 s_rdpkt = ssh2_rdpkt;
930 * This is a v1 server. Begin v1 protocol.
932 sprintf(vstring, "SSH-%s-PuTTY\n",
933 (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5"));
934 sprintf(vlog, "We claim version: %s", vstring);
935 vlog[strcspn(vlog, "\r\n")] = '\0';
937 logevent("Using SSH protocol version 1");
938 sk_write(s, vstring, strlen(vstring));
939 ssh_protocol = ssh1_protocol;
941 s_rdpkt = ssh1_rdpkt;
947 static void ssh_gotdata(unsigned char *data, int datalen)
952 * To begin with, feed the characters one by one to the
953 * protocol initialisation / selection function do_ssh_init().
954 * When that returns 0, we're done with the initial greeting
955 * exchange and can move on to packet discipline.
960 crReturnV; /* more data please */
961 ret = do_ssh_init(*data);
968 * We emerge from that loop when the initial negotiation is
969 * over and we have selected an s_rdpkt function. Now pass
970 * everything to s_rdpkt, and then pass the resulting packets
971 * to the proper protocol handler.
976 while (datalen > 0) {
977 if ( s_rdpkt(&data, &datalen) == 0 ) {
978 ssh_protocol(NULL, 0, 1);
979 if (ssh_state == SSH_STATE_CLOSED) {
989 static int ssh_receive(Socket s, int urgent, char *data, int len) {
991 /* Connection has closed. */
996 ssh_gotdata (data, len);
997 if (ssh_state == SSH_STATE_CLOSED) {
1008 * Connect to specified host and port.
1009 * Returns an error message, or NULL on success.
1010 * Also places the canonical host name into `realhost'.
1012 static char *connect_to_host(char *host, int port, char **realhost)
1021 savedhost = malloc(1+strlen(host));
1023 fatalbox("Out of memory");
1024 strcpy(savedhost, host);
1027 port = 22; /* default ssh port */
1040 addr = sk_namelookup(host, realhost);
1041 if ( (err = sk_addr_error(addr)) )
1051 s = sk_new(addr, port, ssh_receive);
1052 if ( (err = sk_socket_error(s)) )
1056 sk_write(s, "connect ", 8);
1057 sk_write(s, FWhost, strlen(FWhost));
1060 sprintf(buf, " %d\n", FWport);
1061 sk_write(s, buf, strlen(buf));
1069 * Handle the key exchange and user authentication phases.
1071 static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
1074 unsigned char *rsabuf, *keystr1, *keystr2;
1075 unsigned char cookie[8];
1076 struct RSAKey servkey, hostkey;
1077 struct MD5Context md5c;
1078 static unsigned long supported_ciphers_mask, supported_auths_mask;
1079 static int tried_publickey;
1080 static unsigned char session_id[16];
1082 static char username[100];
1086 if (!ispkt) crWaitUntil(ispkt);
1088 if (pktin.type != SSH1_SMSG_PUBLIC_KEY) {
1089 bombout(("Public key packet not received"));
1093 logevent("Received public keys");
1095 memcpy(cookie, pktin.body, 8);
1097 i = makekey(pktin.body+8, &servkey, &keystr1, 0);
1098 j = makekey(pktin.body+8+i, &hostkey, &keystr2, 0);
1101 * Log the host key fingerprint.
1105 logevent("Host key fingerprint is:");
1106 strcpy(logmsg, " ");
1107 hostkey.comment = NULL;
1108 rsa_fingerprint(logmsg+strlen(logmsg), sizeof(logmsg)-strlen(logmsg),
1113 supported_ciphers_mask = GET_32BIT(pktin.body+12+i+j);
1114 supported_auths_mask = GET_32BIT(pktin.body+16+i+j);
1117 MD5Update(&md5c, keystr2, hostkey.bytes);
1118 MD5Update(&md5c, keystr1, servkey.bytes);
1119 MD5Update(&md5c, pktin.body, 8);
1120 MD5Final(session_id, &md5c);
1122 for (i=0; i<32; i++)
1123 session_key[i] = random_byte();
1125 len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
1127 rsabuf = malloc(len);
1129 fatalbox("Out of memory");
1132 * Verify the host key.
1136 * First format the key into a string.
1138 int len = rsastr_len(&hostkey);
1139 char fingerprint[100];
1140 char *keystr = malloc(len);
1142 fatalbox("Out of memory");
1143 rsastr_fmt(keystr, &hostkey);
1144 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
1145 verify_ssh_host_key(savedhost, savedport, "rsa", keystr, fingerprint);
1149 for (i=0; i<32; i++) {
1150 rsabuf[i] = session_key[i];
1152 rsabuf[i] ^= session_id[i];
1155 if (hostkey.bytes > servkey.bytes) {
1156 rsaencrypt(rsabuf, 32, &servkey);
1157 rsaencrypt(rsabuf, servkey.bytes, &hostkey);
1159 rsaencrypt(rsabuf, 32, &hostkey);
1160 rsaencrypt(rsabuf, hostkey.bytes, &servkey);
1163 logevent("Encrypted session key");
1165 cipher_type = cfg.cipher == CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH :
1166 cfg.cipher == CIPHER_DES ? SSH_CIPHER_DES :
1168 if ((supported_ciphers_mask & (1 << cipher_type)) == 0) {
1169 c_write("Selected cipher not supported, falling back to 3DES\r\n", 53);
1170 cipher_type = SSH_CIPHER_3DES;
1172 switch (cipher_type) {
1173 case SSH_CIPHER_3DES: logevent("Using 3DES encryption"); break;
1174 case SSH_CIPHER_DES: logevent("Using single-DES encryption"); break;
1175 case SSH_CIPHER_BLOWFISH: logevent("Using Blowfish encryption"); break;
1178 send_packet(SSH1_CMSG_SESSION_KEY,
1179 PKT_CHAR, cipher_type,
1180 PKT_DATA, cookie, 8,
1181 PKT_CHAR, (len*8) >> 8, PKT_CHAR, (len*8) & 0xFF,
1182 PKT_DATA, rsabuf, len,
1186 logevent("Trying to enable encryption...");
1190 cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
1191 cipher_type == SSH_CIPHER_DES ? &ssh_des :
1193 cipher->sesskey(session_key);
1197 if (pktin.type != SSH1_SMSG_SUCCESS) {
1198 bombout(("Encryption not successfully enabled"));
1202 logevent("Successfully started encryption");
1208 if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
1209 c_write("login as: ", 10);
1212 crWaitUntil(!ispkt);
1213 while (inlen--) switch (c = *in++) {
1220 c_write("\b \b", 3);
1226 c_write("\b \b", 3);
1235 if (((c >= ' ' && c <= '~') ||
1236 ((unsigned char)c >= 160)) && pos < 40) {
1237 username[pos++] = c;
1244 username[strcspn(username, "\n\r")] = '\0';
1247 strncpy(username, cfg.username, 99);
1248 username[99] = '\0';
1249 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
1250 sprintf(stuff, "Sent username \"%s\".\r\n", username);
1251 c_write(stuff, strlen(stuff));
1255 send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END);
1257 char userlog[20+sizeof(username)];
1258 sprintf(userlog, "Sent username \"%s\"", username);
1265 tried_publickey = 0;
1267 while (pktin.type == SSH1_SMSG_FAILURE) {
1268 static char password[100];
1269 static char prompt[200];
1272 static int pwpkt_type;
1274 * Show password prompt, having first obtained it via a TIS
1275 * or CryptoCard exchange if we're doing TIS or CryptoCard
1278 pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
1279 if (agent_exists()) {
1281 * Attempt RSA authentication using Pageant.
1283 static unsigned char request[5], *response, *p;
1284 static int responselen;
1285 static int i, nkeys;
1286 static int authed = FALSE;
1289 logevent("Pageant is running. Requesting keys.");
1291 /* Request the keys held by the agent. */
1292 PUT_32BIT(request, 1);
1293 request[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES;
1294 agent_query(request, 5, &r, &responselen);
1295 response = (unsigned char *)r;
1298 nkeys = GET_32BIT(p); p += 4;
1299 { char buf[64]; sprintf(buf, "Pageant has %d keys", nkeys);
1301 for (i = 0; i < nkeys; i++) {
1302 static struct RSAKey key;
1303 static Bignum challenge;
1304 static char *commentp;
1305 static int commentlen;
1307 { char buf[64]; sprintf(buf, "Trying Pageant key #%d", i);
1310 p += ssh1_read_bignum(p, &key.exponent);
1311 p += ssh1_read_bignum(p, &key.modulus);
1312 commentlen = GET_32BIT(p); p += 4;
1313 commentp = p; p += commentlen;
1314 send_packet(SSH1_CMSG_AUTH_RSA,
1315 PKT_BIGNUM, key.modulus, PKT_END);
1317 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
1318 logevent("Key refused");
1321 logevent("Received RSA challenge");
1322 ssh1_read_bignum(pktin.body, &challenge);
1324 char *agentreq, *q, *ret;
1326 len = 1 + 4; /* message type, bit count */
1327 len += ssh1_bignum_length(key.exponent);
1328 len += ssh1_bignum_length(key.modulus);
1329 len += ssh1_bignum_length(challenge);
1330 len += 16; /* session id */
1331 len += 4; /* response format */
1332 agentreq = malloc(4 + len);
1333 PUT_32BIT(agentreq, len);
1335 *q++ = SSH_AGENTC_RSA_CHALLENGE;
1336 PUT_32BIT(q, ssh1_bignum_bitcount(key.modulus));
1338 q += ssh1_write_bignum(q, key.exponent);
1339 q += ssh1_write_bignum(q, key.modulus);
1340 q += ssh1_write_bignum(q, challenge);
1341 memcpy(q, session_id, 16); q += 16;
1342 PUT_32BIT(q, 1); /* response format */
1343 agent_query(agentreq, len+4, &ret, &retlen);
1346 if (ret[4] == SSH_AGENT_RSA_RESPONSE) {
1347 logevent("Sending Pageant's response");
1348 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
1349 PKT_DATA, ret+5, 16, PKT_END);
1352 if (pktin.type == SSH1_SMSG_SUCCESS) {
1353 logevent("Pageant's response accepted");
1354 if (flags & FLAG_VERBOSE) {
1355 c_write("Authenticated using RSA key \"",
1357 c_write(commentp, commentlen);
1358 c_write("\" from agent\r\n", 14);
1362 logevent("Pageant's response not accepted");
1364 logevent("Pageant failed to answer challenge");
1368 logevent("No reply received from Pageant");
1371 freebn(key.exponent);
1372 freebn(key.modulus);
1381 if (*cfg.keyfile && !tried_publickey)
1382 pwpkt_type = SSH1_CMSG_AUTH_RSA;
1384 if (pktin.type == SSH1_SMSG_FAILURE &&
1386 (supported_auths_mask & (1<<SSH1_AUTH_TIS))) {
1387 pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
1388 logevent("Requested TIS authentication");
1389 send_packet(SSH1_CMSG_AUTH_TIS, PKT_END);
1391 if (pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
1392 logevent("TIS authentication declined");
1393 if (flags & FLAG_INTERACTIVE)
1394 c_write("TIS authentication refused.\r\n", 29);
1396 int challengelen = ((pktin.body[0] << 24) |
1397 (pktin.body[1] << 16) |
1398 (pktin.body[2] << 8) |
1400 logevent("Received TIS challenge");
1401 if (challengelen > sizeof(prompt)-1)
1402 challengelen = sizeof(prompt)-1; /* prevent overrun */
1403 memcpy(prompt, pktin.body+4, challengelen);
1404 prompt[challengelen] = '\0';
1407 if (pktin.type == SSH1_SMSG_FAILURE &&
1409 (supported_auths_mask & (1<<SSH1_AUTH_CCARD))) {
1410 pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
1411 logevent("Requested CryptoCard authentication");
1412 send_packet(SSH1_CMSG_AUTH_CCARD, PKT_END);
1414 if (pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
1415 logevent("CryptoCard authentication declined");
1416 c_write("CryptoCard authentication refused.\r\n", 29);
1418 int challengelen = ((pktin.body[0] << 24) |
1419 (pktin.body[1] << 16) |
1420 (pktin.body[2] << 8) |
1422 logevent("Received CryptoCard challenge");
1423 if (challengelen > sizeof(prompt)-1)
1424 challengelen = sizeof(prompt)-1; /* prevent overrun */
1425 memcpy(prompt, pktin.body+4, challengelen);
1426 strncpy(prompt + challengelen, "\r\nResponse : ",
1427 sizeof(prompt)-challengelen);
1428 prompt[sizeof(prompt)-1] = '\0';
1431 if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
1432 sprintf(prompt, "%.90s@%.90s's password: ",
1433 username, savedhost);
1435 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
1436 char *comment = NULL;
1437 if (flags & FLAG_VERBOSE)
1438 c_write("Trying public key authentication.\r\n", 35);
1439 if (!rsakey_encrypted(cfg.keyfile, &comment)) {
1440 if (flags & FLAG_VERBOSE)
1441 c_write("No passphrase required.\r\n", 25);
1444 sprintf(prompt, "Passphrase for key \"%.100s\": ", comment);
1448 if (ssh_get_password) {
1449 if (!ssh_get_password(prompt, password, sizeof(password))) {
1451 * get_password failed to get a password (for
1452 * example because one was supplied on the command
1453 * line which has already failed to work).
1456 logevent("No more passwords to try");
1457 ssh_state = SSH_STATE_CLOSED;
1461 c_write(prompt, strlen(prompt));
1465 crWaitUntil(!ispkt);
1466 while (inlen--) switch (c = *in++) {
1483 if (((c >= ' ' && c <= '~') ||
1484 ((unsigned char)c >= 160)) && pos < sizeof(password))
1485 password[pos++] = c;
1493 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
1495 * Try public key authentication with the specified
1498 static struct RSAKey pubkey;
1499 static Bignum challenge, response;
1501 static unsigned char buffer[32];
1503 tried_publickey = 1;
1504 i = loadrsakey(cfg.keyfile, &pubkey, NULL, password);
1506 c_write("Couldn't load public key from ", 30);
1507 c_write(cfg.keyfile, strlen(cfg.keyfile));
1508 c_write(".\r\n", 3);
1509 continue; /* go and try password */
1512 c_write("Wrong passphrase.\r\n", 19);
1513 tried_publickey = 0;
1514 continue; /* try again */
1518 * Send a public key attempt.
1520 send_packet(SSH1_CMSG_AUTH_RSA,
1521 PKT_BIGNUM, pubkey.modulus, PKT_END);
1524 if (pktin.type == SSH1_SMSG_FAILURE) {
1525 c_write("Server refused our public key.\r\n", 32);
1526 continue; /* go and try password */
1528 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
1529 bombout(("Bizarre response to offer of public key"));
1532 ssh1_read_bignum(pktin.body, &challenge);
1533 response = rsadecrypt(challenge, &pubkey);
1534 freebn(pubkey.private_exponent); /* burn the evidence */
1536 for (i = 0; i < 32; i += 2) {
1537 buffer[i] = response[16-i/2] >> 8;
1538 buffer[i+1] = response[16-i/2] & 0xFF;
1542 MD5Update(&md5c, buffer, 32);
1543 MD5Update(&md5c, session_id, 16);
1544 MD5Final(buffer, &md5c);
1546 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
1547 PKT_DATA, buffer, 16, PKT_END);
1550 if (pktin.type == SSH1_SMSG_FAILURE) {
1551 if (flags & FLAG_VERBOSE)
1552 c_write("Failed to authenticate with our public key.\r\n",
1554 continue; /* go and try password */
1555 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
1556 bombout(("Bizarre response to RSA authentication response"));
1560 break; /* we're through! */
1562 send_packet(pwpkt_type, PKT_STR, password, PKT_END);
1564 logevent("Sent password");
1565 memset(password, 0, strlen(password));
1567 if (pktin.type == SSH1_SMSG_FAILURE) {
1568 if (flags & FLAG_VERBOSE)
1569 c_write("Access denied\r\n", 15);
1570 logevent("Authentication refused");
1571 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
1572 logevent("Received disconnect request");
1573 ssh_state = SSH_STATE_CLOSED;
1575 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
1576 bombout(("Strange packet received, type %d", pktin.type));
1581 logevent("Authentication successful");
1586 static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) {
1591 while (!do_ssh1_login(in, inlen, ispkt)) {
1594 if (ssh_state == SSH_STATE_CLOSED)
1597 if (cfg.agentfwd && agent_exists()) {
1598 logevent("Requesting agent forwarding");
1599 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
1600 do { crReturnV; } while (!ispkt);
1601 if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
1602 bombout(("Protocol confusion"));
1604 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1605 logevent("Agent forwarding refused");
1607 logevent("Agent forwarding enabled");
1611 send_packet(SSH1_CMSG_REQUEST_PTY,
1612 PKT_STR, cfg.termtype,
1613 PKT_INT, rows, PKT_INT, cols,
1614 PKT_INT, 0, PKT_INT, 0,
1617 ssh_state = SSH_STATE_INTERMED;
1618 do { crReturnV; } while (!ispkt);
1619 if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
1620 bombout(("Protocol confusion"));
1622 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1623 c_write("Server refused to allocate pty\r\n", 32);
1625 logevent("Allocated pty");
1628 if (*cfg.remote_cmd)
1629 send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cfg.remote_cmd, PKT_END);
1631 send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END);
1632 logevent("Started session");
1634 ssh_state = SSH_STATE_SESSION;
1639 ssh_channels = newtree234(ssh_channelcmp);
1644 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
1645 pktin.type == SSH1_SMSG_STDERR_DATA) {
1646 long len = GET_32BIT(pktin.body);
1647 from_backend(pktin.type == SSH1_SMSG_STDERR_DATA,
1649 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
1650 ssh_state = SSH_STATE_CLOSED;
1651 logevent("Received disconnect request");
1653 } else if (pktin.type == SSH1_SMSG_AGENT_OPEN) {
1654 /* Remote side is trying to open a channel to talk to our
1655 * agent. Give them back a local channel number. */
1657 struct ssh_channel *c;
1659 for (c = first234(ssh_channels, &e); c; c = next234(&e)) {
1661 break; /* found a free number */
1664 c = malloc(sizeof(struct ssh_channel));
1665 c->remoteid = GET_32BIT(pktin.body);
1668 c->type = SSH1_SMSG_AGENT_OPEN; /* identify channel type */
1669 c->u.a.lensofar = 0;
1670 add234(ssh_channels, c);
1671 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
1672 PKT_INT, c->remoteid, PKT_INT, c->localid,
1674 } else if (pktin.type == SSH1_MSG_CHANNEL_CLOSE ||
1675 pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
1676 /* Remote side closes a channel. */
1677 unsigned i = GET_32BIT(pktin.body);
1678 struct ssh_channel *c;
1679 c = find234(ssh_channels, &i, ssh_channelfind);
1682 closetype = (pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
1683 send_packet(pktin.type, PKT_INT, c->remoteid, PKT_END);
1684 c->closes |= closetype;
1685 if (c->closes == 3) {
1686 del234(ssh_channels, c);
1690 } else if (pktin.type == SSH1_MSG_CHANNEL_DATA) {
1691 /* Data sent down one of our channels. */
1692 int i = GET_32BIT(pktin.body);
1693 int len = GET_32BIT(pktin.body+4);
1694 unsigned char *p = pktin.body+8;
1695 struct ssh_channel *c;
1696 c = find234(ssh_channels, &i, ssh_channelfind);
1699 case SSH1_SMSG_AGENT_OPEN:
1700 /* Data for an agent message. Buffer it. */
1702 if (c->u.a.lensofar < 4) {
1703 int l = min(4 - c->u.a.lensofar, len);
1704 memcpy(c->u.a.msglen + c->u.a.lensofar, p, l);
1705 p += l; len -= l; c->u.a.lensofar += l;
1707 if (c->u.a.lensofar == 4) {
1708 c->u.a.totallen = 4 + GET_32BIT(c->u.a.msglen);
1709 c->u.a.message = malloc(c->u.a.totallen);
1710 memcpy(c->u.a.message, c->u.a.msglen, 4);
1712 if (c->u.a.lensofar >= 4 && len > 0) {
1713 int l = min(c->u.a.totallen - c->u.a.lensofar, len);
1714 memcpy(c->u.a.message + c->u.a.lensofar, p, l);
1715 p += l; len -= l; c->u.a.lensofar += l;
1717 if (c->u.a.lensofar == c->u.a.totallen) {
1718 void *reply, *sentreply;
1720 agent_query(c->u.a.message, c->u.a.totallen,
1725 /* Fake SSH_AGENT_FAILURE. */
1726 sentreply = "\0\0\0\1\5";
1729 send_packet(SSH1_MSG_CHANNEL_DATA,
1730 PKT_INT, c->remoteid,
1732 PKT_DATA, sentreply, replylen,
1736 free(c->u.a.message);
1737 c->u.a.lensofar = 0;
1743 } else if (pktin.type == SSH1_SMSG_SUCCESS) {
1744 /* may be from EXEC_SHELL on some servers */
1745 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1746 /* may be from EXEC_SHELL on some servers
1747 * if no pty is available or in other odd cases. Ignore */
1748 } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) {
1749 send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
1751 bombout(("Strange packet received: type %d", pktin.type));
1756 int len = min(inlen, 512);
1757 send_packet(SSH1_CMSG_STDIN_DATA,
1758 PKT_INT, len, PKT_DATA, in, len, PKT_END);
1769 * Utility routine for decoding comma-separated strings in KEXINIT.
1771 static int in_commasep_string(char *needle, char *haystack, int haylen) {
1772 int needlen = strlen(needle);
1775 * Is it at the start of the string?
1777 if (haylen >= needlen && /* haystack is long enough */
1778 !memcmp(needle, haystack, needlen) && /* initial match */
1779 (haylen == needlen || haystack[needlen] == ',')
1780 /* either , or EOS follows */
1784 * If not, search for the next comma and resume after that.
1785 * If no comma found, terminate.
1787 while (haylen > 0 && *haystack != ',')
1788 haylen--, haystack++;
1791 haylen--, haystack++; /* skip over comma itself */
1796 * SSH2 key creation method.
1798 static void ssh2_mkkey(Bignum K, char *H, char chr, char *keyspace) {
1800 /* First 20 bytes. */
1803 SHA_Bytes(&s, H, 20);
1804 SHA_Bytes(&s, &chr, 1);
1805 SHA_Bytes(&s, H, 20);
1806 SHA_Final(&s, keyspace);
1807 /* Next 20 bytes. */
1810 SHA_Bytes(&s, H, 20);
1811 SHA_Bytes(&s, keyspace, 20);
1812 SHA_Final(&s, keyspace+20);
1816 * Handle the SSH2 transport layer.
1818 static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt)
1822 static Bignum e, f, K;
1823 static const struct ssh_mac **maclist;
1825 static const struct ssh_cipher *cscipher_tobe = NULL;
1826 static const struct ssh_cipher *sccipher_tobe = NULL;
1827 static const struct ssh_mac *csmac_tobe = NULL;
1828 static const struct ssh_mac *scmac_tobe = NULL;
1829 static const struct ssh_compress *cscomp_tobe = NULL;
1830 static const struct ssh_compress *sccomp_tobe = NULL;
1831 static char *hostkeydata, *sigdata, *keystr, *fingerprint;
1832 static int hostkeylen, siglen;
1833 static unsigned char exchange_hash[20];
1834 static unsigned char keyspace[40];
1835 static const struct ssh_cipher *preferred_cipher;
1841 * Set up the preferred cipher.
1843 if (cfg.cipher == CIPHER_BLOWFISH) {
1844 preferred_cipher = &ssh_blowfish_ssh2;
1845 } else if (cfg.cipher == CIPHER_DES) {
1846 logevent("Single DES not supported in SSH2; using 3DES");
1847 preferred_cipher = &ssh_3des_ssh2;
1848 } else if (cfg.cipher == CIPHER_3DES) {
1849 preferred_cipher = &ssh_3des_ssh2;
1851 /* Shouldn't happen, but we do want to initialise to _something_. */
1852 preferred_cipher = &ssh_3des_ssh2;
1856 * Be prepared to work around the buggy MAC problem.
1859 maclist = buggymacs, nmacs = lenof(buggymacs);
1861 maclist = macs, nmacs = lenof(macs);
1865 * Construct and send our key exchange packet.
1867 ssh2_pkt_init(SSH2_MSG_KEXINIT);
1868 for (i = 0; i < 16; i++)
1869 ssh2_pkt_addbyte((unsigned char)random_byte());
1870 /* List key exchange algorithms. */
1871 ssh2_pkt_addstring_start();
1872 for (i = 0; i < lenof(kex_algs); i++) {
1873 ssh2_pkt_addstring_str(kex_algs[i]->name);
1874 if (i < lenof(kex_algs)-1)
1875 ssh2_pkt_addstring_str(",");
1877 /* List server host key algorithms. */
1878 ssh2_pkt_addstring_start();
1879 for (i = 0; i < lenof(hostkey_algs); i++) {
1880 ssh2_pkt_addstring_str(hostkey_algs[i]->name);
1881 if (i < lenof(hostkey_algs)-1)
1882 ssh2_pkt_addstring_str(",");
1884 /* List client->server encryption algorithms. */
1885 ssh2_pkt_addstring_start();
1886 for (i = 0; i < lenof(ciphers)+1; i++) {
1887 const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
1888 ssh2_pkt_addstring_str(c->name);
1889 if (i < lenof(ciphers))
1890 ssh2_pkt_addstring_str(",");
1892 /* List server->client encryption algorithms. */
1893 ssh2_pkt_addstring_start();
1894 for (i = 0; i < lenof(ciphers)+1; i++) {
1895 const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
1896 ssh2_pkt_addstring_str(c->name);
1897 if (i < lenof(ciphers))
1898 ssh2_pkt_addstring_str(",");
1900 /* List client->server MAC algorithms. */
1901 ssh2_pkt_addstring_start();
1902 for (i = 0; i < nmacs; i++) {
1903 ssh2_pkt_addstring_str(maclist[i]->name);
1905 ssh2_pkt_addstring_str(",");
1907 /* List server->client MAC algorithms. */
1908 ssh2_pkt_addstring_start();
1909 for (i = 0; i < nmacs; i++) {
1910 ssh2_pkt_addstring_str(maclist[i]->name);
1912 ssh2_pkt_addstring_str(",");
1914 /* List client->server compression algorithms. */
1915 ssh2_pkt_addstring_start();
1916 for (i = 0; i < lenof(compressions); i++) {
1917 ssh2_pkt_addstring_str(compressions[i]->name);
1918 if (i < lenof(compressions)-1)
1919 ssh2_pkt_addstring_str(",");
1921 /* List server->client compression algorithms. */
1922 ssh2_pkt_addstring_start();
1923 for (i = 0; i < lenof(compressions); i++) {
1924 ssh2_pkt_addstring_str(compressions[i]->name);
1925 if (i < lenof(compressions)-1)
1926 ssh2_pkt_addstring_str(",");
1928 /* List client->server languages. Empty list. */
1929 ssh2_pkt_addstring_start();
1930 /* List server->client languages. Empty list. */
1931 ssh2_pkt_addstring_start();
1932 /* First KEX packet does _not_ follow, because we're not that brave. */
1933 ssh2_pkt_addbool(FALSE);
1935 ssh2_pkt_adduint32(0);
1936 sha_string(&exhash, pktout.data+5, pktout.length-5);
1939 if (!ispkt) crWaitUntil(ispkt);
1940 sha_string(&exhash, pktin.data+5, pktin.length-5);
1943 * Now examine the other side's KEXINIT to see what we're up
1946 if (pktin.type != SSH2_MSG_KEXINIT) {
1947 bombout(("expected key exchange packet from server"));
1950 kex = NULL; hostkey = NULL; cscipher_tobe = NULL; sccipher_tobe = NULL;
1951 csmac_tobe = NULL; scmac_tobe = NULL; cscomp_tobe = NULL; sccomp_tobe = NULL;
1952 pktin.savedpos += 16; /* skip garbage cookie */
1953 ssh2_pkt_getstring(&str, &len); /* key exchange algorithms */
1954 for (i = 0; i < lenof(kex_algs); i++) {
1955 if (in_commasep_string(kex_algs[i]->name, str, len)) {
1960 ssh2_pkt_getstring(&str, &len); /* host key algorithms */
1961 for (i = 0; i < lenof(hostkey_algs); i++) {
1962 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
1963 hostkey = hostkey_algs[i];
1967 ssh2_pkt_getstring(&str, &len); /* client->server cipher */
1968 for (i = 0; i < lenof(ciphers)+1; i++) {
1969 const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
1970 if (in_commasep_string(c->name, str, len)) {
1975 ssh2_pkt_getstring(&str, &len); /* server->client cipher */
1976 for (i = 0; i < lenof(ciphers)+1; i++) {
1977 const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
1978 if (in_commasep_string(c->name, str, len)) {
1983 ssh2_pkt_getstring(&str, &len); /* client->server mac */
1984 for (i = 0; i < nmacs; i++) {
1985 if (in_commasep_string(maclist[i]->name, str, len)) {
1986 csmac_tobe = maclist[i];
1990 ssh2_pkt_getstring(&str, &len); /* server->client mac */
1991 for (i = 0; i < nmacs; i++) {
1992 if (in_commasep_string(maclist[i]->name, str, len)) {
1993 scmac_tobe = maclist[i];
1997 ssh2_pkt_getstring(&str, &len); /* client->server compression */
1998 for (i = 0; i < lenof(compressions); i++) {
1999 if (in_commasep_string(compressions[i]->name, str, len)) {
2000 cscomp_tobe = compressions[i];
2004 ssh2_pkt_getstring(&str, &len); /* server->client compression */
2005 for (i = 0; i < lenof(compressions); i++) {
2006 if (in_commasep_string(compressions[i]->name, str, len)) {
2007 sccomp_tobe = compressions[i];
2013 * Currently we only support Diffie-Hellman and DSS, so let's
2014 * bomb out if those aren't selected.
2016 if (kex != &ssh_diffiehellman || hostkey != &ssh_dss) {
2017 bombout(("internal fault: chaos in SSH 2 transport layer"));
2022 * Now we begin the fun. Generate and send e for Diffie-Hellman.
2025 ssh2_pkt_init(SSH2_MSG_KEXDH_INIT);
2030 if (pktin.type != SSH2_MSG_KEXDH_REPLY) {
2031 bombout(("expected key exchange packet from server"));
2034 ssh2_pkt_getstring(&hostkeydata, &hostkeylen);
2035 f = ssh2_pkt_getmp();
2036 ssh2_pkt_getstring(&sigdata, &siglen);
2040 sha_string(&exhash, hostkeydata, hostkeylen);
2041 sha_mpint(&exhash, e);
2042 sha_mpint(&exhash, f);
2043 sha_mpint(&exhash, K);
2044 SHA_Final(&exhash, exchange_hash);
2047 debug(("Exchange hash is:\r\n"));
2048 for (i = 0; i < 20; i++)
2049 debug((" %02x", exchange_hash[i]));
2053 hostkey->setkey(hostkeydata, hostkeylen);
2054 if (!hostkey->verifysig(sigdata, siglen, exchange_hash, 20)) {
2055 bombout(("Server failed host key check"));
2060 * Expect SSH2_MSG_NEWKEYS from server.
2063 if (pktin.type != SSH2_MSG_NEWKEYS) {
2064 bombout(("expected new-keys packet from server"));
2069 * Authenticate remote host: verify host key. (We've already
2070 * checked the signature of the exchange hash.)
2072 keystr = hostkey->fmtkey();
2073 fingerprint = hostkey->fingerprint();
2074 verify_ssh_host_key(savedhost, savedport, hostkey->keytype,
2075 keystr, fingerprint);
2076 logevent("Host key fingerprint is:");
2077 logevent(fingerprint);
2082 * Send SSH2_MSG_NEWKEYS.
2084 ssh2_pkt_init(SSH2_MSG_NEWKEYS);
2088 * Create and initialise session keys.
2090 cscipher = cscipher_tobe;
2091 sccipher = sccipher_tobe;
2094 cscomp = cscomp_tobe;
2095 sccomp = sccomp_tobe;
2097 * Set IVs after keys.
2099 ssh2_mkkey(K, exchange_hash, 'C', keyspace); cscipher->setcskey(keyspace);
2100 ssh2_mkkey(K, exchange_hash, 'D', keyspace); cscipher->setsckey(keyspace);
2101 ssh2_mkkey(K, exchange_hash, 'A', keyspace); cscipher->setcsiv(keyspace);
2102 ssh2_mkkey(K, exchange_hash, 'B', keyspace); sccipher->setsciv(keyspace);
2103 ssh2_mkkey(K, exchange_hash, 'E', keyspace); csmac->setcskey(keyspace);
2104 ssh2_mkkey(K, exchange_hash, 'F', keyspace); scmac->setsckey(keyspace);
2107 * Now we're encrypting. Begin returning 1 to the protocol main
2108 * function so that other things can run on top of the
2109 * transport. If we ever see a KEXINIT, we must go back to the
2114 } while (!(ispkt && pktin.type == SSH2_MSG_KEXINIT));
2115 goto begin_key_exchange;
2121 * Handle the SSH2 userauth and connection layers.
2123 static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
2125 static unsigned long remote_winsize;
2126 static unsigned long remote_maxpkt;
2131 * Request userauth protocol, and await a response to it.
2133 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
2134 ssh2_pkt_addstring("ssh-userauth");
2136 crWaitUntilV(ispkt);
2137 if (pktin.type != SSH2_MSG_SERVICE_ACCEPT) {
2138 bombout(("Server refused user authentication protocol"));
2143 * FIXME: currently we support only password authentication.
2144 * (This places us technically in violation of the SSH2 spec.
2145 * We must fix this.)
2149 * Get a username and a password.
2151 static char username[100];
2152 static char password[100];
2156 if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
2157 c_write("login as: ", 10);
2160 crWaitUntilV(!ispkt);
2161 while (inlen--) switch (c = *in++) {
2168 c_write("\b \b", 3);
2174 c_write("\b \b", 3);
2183 if (((c >= ' ' && c <= '~') ||
2184 ((unsigned char)c >= 160)) && pos < 40) {
2185 username[pos++] = c;
2192 username[strcspn(username, "\n\r")] = '\0';
2195 strncpy(username, cfg.username, 99);
2196 username[99] = '\0';
2197 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
2198 sprintf(stuff, "Using username \"%s\".\r\n", username);
2199 c_write(stuff, strlen(stuff));
2203 if (ssh_get_password) {
2205 sprintf(prompt, "%.90s@%.90s's password: ", username, savedhost);
2206 if (!ssh_get_password(prompt, password, sizeof(password))) {
2208 * get_password failed to get a password (for
2209 * example because one was supplied on the command
2210 * line which has already failed to work).
2213 logevent("No more passwords to try");
2214 ssh_state = SSH_STATE_CLOSED;
2218 c_write("password: ", 10);
2223 crWaitUntilV(!ispkt);
2224 while (inlen--) switch (c = *in++) {
2241 if (((c >= ' ' && c <= '~') ||
2242 ((unsigned char)c >= 160)) && pos < 40)
2243 password[pos++] = c;
2250 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
2251 ssh2_pkt_addstring(username);
2252 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2253 ssh2_pkt_addstring("password");
2254 ssh2_pkt_addbool(FALSE);
2255 ssh2_pkt_addstring(password);
2258 crWaitUntilV(ispkt);
2259 if (pktin.type != SSH2_MSG_USERAUTH_SUCCESS) {
2260 c_write("Access denied\r\n", 15);
2261 logevent("Authentication refused");
2267 * Now we're authenticated for the connection protocol. The
2268 * connection protocol will automatically have started at this
2269 * point; there's no need to send SERVICE_REQUEST.
2273 * So now create a channel with a session in it.
2275 mainchan = malloc(sizeof(struct ssh_channel));
2276 mainchan->localid = 100; /* as good as any */
2277 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
2278 ssh2_pkt_addstring("session");
2279 ssh2_pkt_adduint32(mainchan->localid);
2280 ssh2_pkt_adduint32(0x8000UL); /* our window size */
2281 ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
2283 crWaitUntilV(ispkt);
2284 if (pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
2285 bombout(("Server refused to open a session"));
2287 /* FIXME: error data comes back in FAILURE packet */
2289 if (ssh2_pkt_getuint32() != mainchan->localid) {
2290 bombout(("Server's channel confirmation cited wrong channel"));
2293 mainchan->remoteid = ssh2_pkt_getuint32();
2294 mainchan->u.v2.remwindow = ssh2_pkt_getuint32();
2295 mainchan->u.v2.remmaxpkt = ssh2_pkt_getuint32();
2296 mainchan->u.v2.outbuffer = NULL;
2297 mainchan->u.v2.outbuflen = mainchan->u.v2.outbufsize = 0;
2298 logevent("Opened channel for session");
2301 * Now allocate a pty for the session.
2304 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
2305 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
2306 ssh2_pkt_addstring("pty-req");
2307 ssh2_pkt_addbool(1); /* want reply */
2308 ssh2_pkt_addstring(cfg.termtype);
2309 ssh2_pkt_adduint32(cols);
2310 ssh2_pkt_adduint32(rows);
2311 ssh2_pkt_adduint32(0); /* pixel width */
2312 ssh2_pkt_adduint32(0); /* pixel height */
2313 ssh2_pkt_addstring_start();
2314 ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
2316 ssh_state = SSH_STATE_INTERMED;
2319 crWaitUntilV(ispkt);
2320 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2321 /* FIXME: be able to handle other channels here */
2322 if (ssh2_pkt_getuint32() != mainchan->localid)
2323 continue; /* wrong channel */
2324 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2326 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2328 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
2329 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
2330 bombout(("Server got confused by pty request"));
2333 c_write("Server refused to allocate pty\r\n", 32);
2335 logevent("Allocated pty");
2340 * Start a shell or a remote command.
2342 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
2343 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
2344 if (*cfg.remote_cmd) {
2345 ssh2_pkt_addstring("exec");
2346 ssh2_pkt_addbool(1); /* want reply */
2347 ssh2_pkt_addstring(cfg.remote_cmd);
2349 ssh2_pkt_addstring("shell");
2350 ssh2_pkt_addbool(1); /* want reply */
2354 crWaitUntilV(ispkt);
2355 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2356 /* FIXME: be able to handle other channels here */
2357 if (ssh2_pkt_getuint32() != mainchan->localid)
2358 continue; /* wrong channel */
2359 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2361 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2362 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
2363 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
2364 bombout(("Server got confused by shell/command request"));
2367 bombout(("Server refused to start a shell/command"));
2370 logevent("Started a shell/command");
2373 ssh_state = SSH_STATE_SESSION;
2383 static int try_send;
2387 if (pktin.type == SSH2_MSG_CHANNEL_DATA ||
2388 pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
2391 /* FIXME: be able to handle other channels here */
2392 if (ssh2_pkt_getuint32() != mainchan->localid)
2393 continue; /* wrong channel */
2394 if (pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
2395 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR)
2396 continue; /* extended but not stderr */
2397 ssh2_pkt_getstring(&data, &length);
2399 from_backend(pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA,
2402 * Enlarge the window again at the remote side,
2403 * just in case it ever runs down and they fail
2404 * to send us any more data.
2406 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2407 ssh2_pkt_adduint32(mainchan->remoteid);
2408 ssh2_pkt_adduint32(length);
2411 } else if (pktin.type == SSH2_MSG_DISCONNECT) {
2412 ssh_state = SSH_STATE_CLOSED;
2413 logevent("Received disconnect message");
2415 } else if (pktin.type == SSH2_MSG_CHANNEL_REQUEST) {
2416 continue; /* exit status et al; ignore (FIXME?) */
2417 } else if (pktin.type == SSH2_MSG_CHANNEL_EOF) {
2418 continue; /* remote sends EOF; ignore */
2419 } else if (pktin.type == SSH2_MSG_CHANNEL_CLOSE) {
2420 /* FIXME: be able to handle other channels here */
2421 if (ssh2_pkt_getuint32() != mainchan->localid)
2422 continue; /* wrong channel */
2423 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
2424 ssh2_pkt_adduint32(mainchan->remoteid);
2426 /* FIXME: mark the channel as closed */
2427 if (1 /* FIXME: "all channels are closed" */) {
2428 logevent("All channels closed. Disconnecting");
2429 ssh2_pkt_init(SSH2_MSG_DISCONNECT);
2431 ssh_state = SSH_STATE_CLOSED;
2434 continue; /* remote sends close; ignore (FIXME) */
2435 } else if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2436 /* FIXME: be able to handle other channels here */
2437 if (ssh2_pkt_getuint32() != mainchan->localid)
2438 continue; /* wrong channel */
2439 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2442 bombout(("Strange packet received: type %d", pktin.type));
2447 * We have spare data. Add it to the channel buffer.
2449 if (mainchan->u.v2.outbufsize <
2450 mainchan->u.v2.outbuflen + inlen) {
2451 mainchan->u.v2.outbufsize =
2452 mainchan->u.v2.outbuflen + inlen + 1024;
2453 mainchan->u.v2.outbuffer = srealloc(mainchan->u.v2.outbuffer,
2454 mainchan->u.v2.outbufsize);
2456 memcpy(mainchan->u.v2.outbuffer + mainchan->u.v2.outbuflen,
2458 mainchan->u.v2.outbuflen += inlen;
2463 * Try to send data on the channel if we can. (FIXME:
2464 * on _all_ channels.)
2466 while (mainchan->u.v2.remwindow > 0 &&
2467 mainchan->u.v2.outbuflen > 0) {
2468 unsigned len = mainchan->u.v2.remwindow;
2469 if (len > mainchan->u.v2.outbuflen)
2470 len = mainchan->u.v2.outbuflen;
2471 if (len > mainchan->u.v2.remmaxpkt)
2472 len = mainchan->u.v2.remmaxpkt;
2473 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
2474 ssh2_pkt_adduint32(mainchan->remoteid);
2475 ssh2_pkt_addstring_start();
2476 ssh2_pkt_addstring_data(mainchan->u.v2.outbuffer, len);
2478 mainchan->u.v2.outbuflen -= len;
2479 memmove(mainchan->u.v2.outbuffer, mainchan->u.v2.outbuffer+len,
2480 mainchan->u.v2.outbuflen);
2481 mainchan->u.v2.remwindow -= len;
2490 * Handle the top-level SSH2 protocol.
2492 static void ssh2_protocol(unsigned char *in, int inlen, int ispkt)
2494 if (do_ssh2_transport(in, inlen, ispkt) == 0)
2496 do_ssh2_authconn(in, inlen, ispkt);
2500 * Called to set up the connection.
2502 * Returns an error message, or NULL on success.
2504 static char *ssh_init (char *host, int port, char **realhost) {
2508 if(crypto_startup() == 0)
2509 return "Microsoft high encryption pack not installed!";
2514 p = connect_to_host(host, port, realhost);
2522 * Called to send data down the Telnet connection.
2524 static void ssh_send (char *buf, int len) {
2528 ssh_protocol(buf, len, 0);
2532 * Called to set the size of the window from SSH's POV.
2534 static void ssh_size(void) {
2535 switch (ssh_state) {
2536 case SSH_STATE_BEFORE_SIZE:
2537 case SSH_STATE_CLOSED:
2538 break; /* do nothing */
2539 case SSH_STATE_INTERMED:
2540 size_needed = TRUE; /* buffer for later */
2542 case SSH_STATE_SESSION:
2544 if (ssh_version == 1) {
2545 send_packet(SSH1_CMSG_WINDOW_SIZE,
2546 PKT_INT, rows, PKT_INT, cols,
2547 PKT_INT, 0, PKT_INT, 0, PKT_END);
2549 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
2550 ssh2_pkt_adduint32(mainchan->remoteid);
2551 ssh2_pkt_addstring("window-change");
2552 ssh2_pkt_addbool(0);
2553 ssh2_pkt_adduint32(cols);
2554 ssh2_pkt_adduint32(rows);
2555 ssh2_pkt_adduint32(0);
2556 ssh2_pkt_adduint32(0);
2564 * Send Telnet special codes. TS_EOF is useful for `plink', so you
2565 * can send an EOF and collect resulting output (e.g. `plink
2568 static void ssh_special (Telnet_Special code) {
2569 if (code == TS_EOF) {
2570 if (ssh_version == 1) {
2571 send_packet(SSH1_CMSG_EOF, PKT_END);
2573 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
2574 ssh2_pkt_adduint32(mainchan->remoteid);
2577 logevent("Sent EOF message");
2578 } else if (code == TS_PING) {
2579 if (ssh_version == 1) {
2580 send_packet(SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
2582 ssh2_pkt_init(SSH2_MSG_IGNORE);
2583 ssh2_pkt_addstring_start();
2591 static Socket ssh_socket(void) { return s; }
2593 static int ssh_sendok(void) { return ssh_send_ok; }
2595 Backend ssh_backend = {