24 #define logevent(s) { logevent(s); \
25 if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \
26 fprintf(stderr, "%s\n", s); }
28 #define bombout(msg) ( ssh_state == SSH_STATE_CLOSED, closesocket(s), \
29 s = INVALID_SOCKET, connection_fatal msg )
31 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
32 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
33 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
34 #define SSH1_CMSG_USER 4 /* 0x4 */
35 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
36 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
37 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
38 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
39 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
40 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
41 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
42 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
43 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
44 #define SSH1_SMSG_FAILURE 15 /* 0xf */
45 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
46 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
47 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
48 #define SSH1_CMSG_EOF 19 /* 0x13 */
49 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
50 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
51 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
52 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
53 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
54 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
55 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
56 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
57 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
58 #define SSH1_MSG_IGNORE 32 /* 0x20 */
59 #define SSH1_MSG_DEBUG 36 /* 0x24 */
60 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
61 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
62 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
63 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
64 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
65 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
67 #define SSH1_AUTH_TIS 5 /* 0x5 */
68 #define SSH1_AUTH_CCARD 16 /* 0x10 */
70 #define SSH_AGENTC_REQUEST_RSA_IDENTITIES 1 /* 0x1 */
71 #define SSH_AGENT_RSA_IDENTITIES_ANSWER 2 /* 0x2 */
72 #define SSH_AGENTC_RSA_CHALLENGE 3 /* 0x3 */
73 #define SSH_AGENT_RSA_RESPONSE 4 /* 0x4 */
74 #define SSH_AGENT_FAILURE 5 /* 0x5 */
75 #define SSH_AGENT_SUCCESS 6 /* 0x6 */
76 #define SSH_AGENTC_ADD_RSA_IDENTITY 7 /* 0x7 */
77 #define SSH_AGENTC_REMOVE_RSA_IDENTITY 8 /* 0x8 */
79 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
80 #define SSH2_MSG_IGNORE 2 /* 0x2 */
81 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
82 #define SSH2_MSG_DEBUG 4 /* 0x4 */
83 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
84 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
85 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
86 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
87 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
88 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
89 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
90 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
91 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
92 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
93 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
94 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
95 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
96 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
97 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
98 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
99 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
100 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
101 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
102 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
103 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
104 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
105 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
106 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
107 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
108 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
110 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
111 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
112 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
113 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
115 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
117 #define GET_32BIT(cp) \
118 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
119 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
120 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
121 ((unsigned long)(unsigned char)(cp)[3]))
123 #define PUT_32BIT(cp, value) { \
124 (cp)[0] = (unsigned char)((value) >> 24); \
125 (cp)[1] = (unsigned char)((value) >> 16); \
126 (cp)[2] = (unsigned char)((value) >> 8); \
127 (cp)[3] = (unsigned char)(value); }
129 enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM };
131 /* Coroutine mechanics for the sillier bits of the code */
132 #define crBegin1 static int crLine = 0;
133 #define crBegin2 switch(crLine) { case 0:;
134 #define crBegin crBegin1; crBegin2;
135 #define crFinish(z) } crLine = 0; return (z)
136 #define crFinishV } crLine = 0; return
137 #define crReturn(z) \
139 crLine=__LINE__; return (z); case __LINE__:;\
143 crLine=__LINE__; return; case __LINE__:;\
145 #define crStop(z) do{ crLine = 0; return (z); }while(0)
146 #define crStopV do{ crLine = 0; return; }while(0)
147 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
148 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
150 extern struct ssh_cipher ssh_3des;
151 extern struct ssh_cipher ssh_3des_ssh2;
152 extern struct ssh_cipher ssh_des;
153 extern struct ssh_cipher ssh_blowfish_ssh1;
154 extern struct ssh_cipher ssh_blowfish_ssh2;
157 * Ciphers for SSH2. We miss out single-DES because it isn't
158 * supported; also 3DES and Blowfish are both done differently from
159 * SSH1. (3DES uses outer chaining; Blowfish has the opposite
160 * endianness and different-sized keys.)
162 * The first entry in this array is set up to be whatever the user
163 * asks for as a cipher. Thereafter there is a fixed preference
164 * order of fallback ciphers.
166 struct ssh_cipher *ciphers[] = { NULL, &ssh_blowfish_ssh2, &ssh_3des_ssh2 };
168 extern struct ssh_kex ssh_diffiehellman;
169 struct ssh_kex *kex_algs[] = { &ssh_diffiehellman };
171 extern struct ssh_hostkey ssh_dss;
172 struct ssh_hostkey *hostkey_algs[] = { &ssh_dss };
174 extern struct ssh_mac ssh_sha1;
176 static SHA_State exhash;
178 static void nullmac_key(unsigned char *key) { }
179 static void nullmac_generate(unsigned char *blk, int len, unsigned long seq) { }
180 static int nullmac_verify(unsigned char *blk, int len, unsigned long seq) { return 1; }
181 struct ssh_mac ssh_mac_none = {
182 nullmac_key, nullmac_key, nullmac_generate, nullmac_verify, "none", 0
184 struct ssh_mac *macs[] = { &ssh_sha1, &ssh_mac_none };
186 struct ssh_compress ssh_comp_none = {
189 struct ssh_compress *compressions[] = { &ssh_comp_none };
191 static SOCKET s = INVALID_SOCKET;
193 static unsigned char session_key[32];
194 static struct ssh_cipher *cipher = NULL;
195 static struct ssh_cipher *cscipher = NULL;
196 static struct ssh_cipher *sccipher = NULL;
197 static struct ssh_mac *csmac = NULL;
198 static struct ssh_mac *scmac = NULL;
199 static struct ssh_compress *cscomp = NULL;
200 static struct ssh_compress *sccomp = NULL;
201 static struct ssh_kex *kex = NULL;
202 static struct ssh_hostkey *hostkey = NULL;
203 int (*ssh_get_password)(const char *prompt, char *str, int maxlen) = NULL;
205 static char *savedhost;
206 static int savedport;
207 static int ssh_send_ok;
210 * 2-3-4 tree storing channels.
213 unsigned remoteid, localid;
217 struct ssh_agent_channel {
218 unsigned char *message;
219 unsigned char msglen[4];
220 int lensofar, totallen;
222 struct ssh2_data_channel {
223 unsigned char *outbuffer;
224 unsigned outbuflen, outbufsize;
225 unsigned remwindow, remmaxpkt;
229 static tree234 *ssh_channels; /* indexed by local id */
230 static int ssh_channelcmp(void *av, void *bv) {
231 struct ssh_channel *a = (struct ssh_channel *)av;
232 struct ssh_channel *b = (struct ssh_channel *)bv;
233 if (a->localid < b->localid) return -1;
234 if (a->localid > b->localid) return +1;
237 static int ssh_channelfind(void *av, void *bv) {
238 unsigned *a = (unsigned *)av;
239 struct ssh_channel *b = (struct ssh_channel *)bv;
240 if (*a < b->localid) return -1;
241 if (*a > b->localid) return +1;
245 static struct ssh_channel *mainchan; /* primary session channel */
248 SSH_STATE_BEFORE_SIZE,
252 } ssh_state = SSH_STATE_BEFORE_SIZE;
254 static int size_needed = FALSE;
256 static void s_write (char *buf, int len) {
258 int i = send (s, buf, len, 0);
261 bombout(("Lost connection while sending"));
269 static int s_read (char *buf, int len) {
272 int i = recv (s, buf, len, 0);
275 len -= i, buf += i, ret += i;
282 static void c_write (char *buf, int len) {
283 if ((flags & FLAG_STDERR)) {
285 for (i = 0; i < len; i++)
287 fputc(buf[i], stderr);
294 static void c_writedata (char *buf, int len) {
308 static struct Packet pktin = { 0, 0, NULL, NULL, 0 };
309 static struct Packet pktout = { 0, 0, NULL, NULL, 0 };
311 static int ssh_version;
312 static void (*ssh_protocol)(unsigned char *in, int inlen, int ispkt);
313 static void ssh1_protocol(unsigned char *in, int inlen, int ispkt);
314 static void ssh2_protocol(unsigned char *in, int inlen, int ispkt);
315 static void ssh_size(void);
317 static int (*s_rdpkt)(unsigned char **data, int *datalen);
320 * Collect incoming data in the incoming packet buffer.
321 * Decipher and verify the packet when it is completely read.
322 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
323 * Update the *data and *datalen variables.
324 * Return the additional nr of bytes needed, or 0 when
325 * a complete packet is available.
327 static int ssh1_rdpkt(unsigned char **data, int *datalen)
329 static long len, pad, biglen, to_read;
330 static unsigned long realcrc, gotcrc;
331 static unsigned char *p;
341 for (i = len = 0; i < 4; i++) {
342 while ((*datalen) == 0)
344 len = (len << 8) + **data;
345 (*data)++, (*datalen)--;
349 if (len == 0x52656d6f) { /* "Remo"te server has closed ... */
350 len = 0x300; /* big enough to carry to end */
356 pktin.length = len - 5;
358 if (pktin.maxlen < biglen) {
359 pktin.maxlen = biglen;
360 pktin.data = (pktin.data == NULL ? malloc(biglen+APIEXTRA) :
361 realloc(pktin.data, biglen+APIEXTRA));
363 fatalbox("Out of memory");
368 while (to_read > 0) {
371 while ((*datalen) == 0)
373 if (chunk > (*datalen))
375 memcpy(p, *data, chunk);
383 cipher->decrypt(pktin.data, biglen);
385 pktin.type = pktin.data[pad];
386 pktin.body = pktin.data + pad + 1;
388 realcrc = crc32(pktin.data, biglen-4);
389 gotcrc = GET_32BIT(pktin.data+biglen-4);
390 if (gotcrc != realcrc) {
391 bombout(("Incorrect CRC received on packet"));
395 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
396 pktin.type == SSH1_SMSG_STDERR_DATA ||
397 pktin.type == SSH1_MSG_DEBUG ||
398 pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE ||
399 pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
400 long strlen = GET_32BIT(pktin.body);
401 if (strlen + 4 != pktin.length) {
402 bombout(("Received data packet with bogus string length"));
407 if (pktin.type == SSH1_MSG_DEBUG) {
408 /* log debug message */
410 int strlen = GET_32BIT(pktin.body);
411 strcpy(buf, "Remote: ");
412 if (strlen > 70) strlen = 70;
413 memcpy(buf+8, pktin.body+4, strlen);
414 buf[8+strlen] = '\0';
417 } else if (pktin.type == SSH1_MSG_IGNORE) {
425 static int ssh2_rdpkt(unsigned char **data, int *datalen)
427 static long len, pad, payload, packetlen, maclen;
429 static int cipherblk;
430 static unsigned long incoming_sequence = 0;
440 cipherblk = cipher->blksize;
446 if (pktin.maxlen < cipherblk) {
447 pktin.maxlen = cipherblk;
448 pktin.data = (pktin.data == NULL ? malloc(cipherblk+APIEXTRA) :
449 realloc(pktin.data, cipherblk+APIEXTRA));
451 fatalbox("Out of memory");
455 * Acquire and decrypt the first block of the packet. This will
456 * contain the length and padding details.
458 for (i = len = 0; i < cipherblk; i++) {
459 while ((*datalen) == 0)
460 crReturn(cipherblk-i);
461 pktin.data[i] = *(*data)++;
465 if (!memcmp(pktin.data, "Remo", 4)) {/* "Remo"te server has closed ... */
470 sccipher->decrypt(pktin.data, cipherblk);
473 * Now get the length and padding figures.
475 len = GET_32BIT(pktin.data);
479 * This enables us to deduce the payload length.
481 payload = len - pad - 1;
483 pktin.length = payload + 5;
486 * So now we can work out the total packet length.
489 maclen = scmac ? scmac->len : 0;
492 * Adjust memory allocation if packet is too big.
494 if (pktin.maxlen < packetlen+maclen) {
495 pktin.maxlen = packetlen+maclen;
496 pktin.data = (pktin.data == NULL ? malloc(pktin.maxlen+APIEXTRA) :
497 realloc(pktin.data, pktin.maxlen+APIEXTRA));
499 fatalbox("Out of memory");
503 * Read and decrypt the remainder of the packet.
505 for (i = cipherblk; i < packetlen + maclen; i++) {
506 while ((*datalen) == 0)
507 crReturn(packetlen + maclen - i);
508 pktin.data[i] = *(*data)++;
511 /* Decrypt everything _except_ the MAC. */
513 sccipher->decrypt(pktin.data + cipherblk, packetlen - cipherblk);
516 debug(("Got packet len=%d pad=%d\r\n", len, pad));
517 for (i = 0; i < packetlen; i++)
518 debug((" %02x", (unsigned char)pktin.data[i]));
525 if (scmac && !scmac->verify(pktin.data, len+4, incoming_sequence)) {
526 bombout(("Incorrect MAC received on packet"));
529 incoming_sequence++; /* whether or not we MACed */
532 pktin.type = pktin.data[5];
534 if (pktin.type == SSH2_MSG_IGNORE || pktin.type == SSH2_MSG_DEBUG)
535 goto next_packet; /* FIXME: print DEBUG message */
540 static void ssh_gotdata(unsigned char *data, int datalen)
542 while (datalen > 0) {
543 if ( s_rdpkt(&data, &datalen) == 0 ) {
544 ssh_protocol(NULL, 0, 1);
545 if (ssh_state == SSH_STATE_CLOSED) {
553 static void s_wrpkt_start(int type, int len) {
556 len += 5; /* type and CRC */
560 pktout.length = len-5;
561 if (pktout.maxlen < biglen) {
562 pktout.maxlen = biglen;
564 /* Allocate enough buffer space for extra block
565 * for MS CryptEncrypt() */
566 pktout.data = (pktout.data == NULL ? malloc(biglen+12) :
567 realloc(pktout.data, biglen+12));
569 pktout.data = (pktout.data == NULL ? malloc(biglen+4) :
570 realloc(pktout.data, biglen+4));
573 fatalbox("Out of memory");
577 pktout.body = pktout.data+4+pad+1;
580 static void s_wrpkt(void) {
581 int pad, len, biglen, i;
584 len = pktout.length + 5; /* type and CRC */
588 pktout.body[-1] = pktout.type;
589 for (i=0; i<pad; i++)
590 pktout.data[i+4] = random_byte();
591 crc = crc32(pktout.data+4, biglen-4);
592 PUT_32BIT(pktout.data+biglen, crc);
593 PUT_32BIT(pktout.data, len);
596 cipher->encrypt(pktout.data+4, biglen);
598 s_write(pktout.data, biglen+4);
602 * Construct a packet with the specified contents and
603 * send it to the server.
605 static void send_packet(int pkttype, ...)
608 unsigned char *p, *argp, argchar;
609 unsigned long argint;
610 int pktlen, argtype, arglen;
614 va_start(args, pkttype);
615 while ((argtype = va_arg(args, int)) != PKT_END) {
618 (void) va_arg(args, int);
622 (void) va_arg(args, char);
626 (void) va_arg(args, unsigned char *);
627 arglen = va_arg(args, int);
631 argp = va_arg(args, unsigned char *);
632 arglen = strlen(argp);
633 pktlen += 4 + arglen;
636 bn = va_arg(args, Bignum);
637 pktlen += ssh1_bignum_length(bn);
645 s_wrpkt_start(pkttype, pktlen);
648 va_start(args, pkttype);
649 while ((argtype = va_arg(args, int)) != PKT_END) {
652 argint = va_arg(args, int);
653 PUT_32BIT(p, argint);
657 argchar = va_arg(args, unsigned char);
662 argp = va_arg(args, unsigned char *);
663 arglen = va_arg(args, int);
664 memcpy(p, argp, arglen);
668 argp = va_arg(args, unsigned char *);
669 arglen = strlen(argp);
670 PUT_32BIT(p, arglen);
671 memcpy(p + 4, argp, arglen);
675 bn = va_arg(args, Bignum);
676 p += ssh1_write_bignum(p, bn);
687 * Connect to specified host and port.
688 * Returns an error message, or NULL on success.
689 * Also places the canonical host name into `realhost'.
691 static char *connect_to_host(char *host, int port, char **realhost)
701 savedhost = malloc(1+strlen(host));
703 fatalbox("Out of memory");
704 strcpy(savedhost, host);
707 port = 22; /* default ssh port */
720 if ( (a = inet_addr(host)) == (unsigned long) INADDR_NONE) {
721 if ( (h = gethostbyname(host)) == NULL)
722 switch (WSAGetLastError()) {
723 case WSAENETDOWN: return "Network is down";
724 case WSAHOST_NOT_FOUND: case WSANO_DATA:
725 return "Host does not exist";
726 case WSATRY_AGAIN: return "Host not found";
727 default: return "gethostbyname: unknown error";
729 memcpy (&a, h->h_addr, sizeof(a));
730 *realhost = h->h_name;
741 s = socket(AF_INET, SOCK_STREAM, 0);
742 if (s == INVALID_SOCKET)
743 switch (WSAGetLastError()) {
744 case WSAENETDOWN: return "Network is down";
745 case WSAEAFNOSUPPORT: return "TCP/IP support not present";
746 default: return "socket(): unknown error";
750 * Bind to local address.
752 addr.sin_family = AF_INET;
753 addr.sin_addr.s_addr = htonl(INADDR_ANY);
754 addr.sin_port = htons(0);
755 if (bind (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
756 switch (WSAGetLastError()) {
757 case WSAENETDOWN: return "Network is down";
758 default: return "bind(): unknown error";
762 * Connect to remote address.
764 addr.sin_addr.s_addr = htonl(a);
765 addr.sin_port = htons((short)port);
766 if (connect (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
767 switch (WSAGetLastError()) {
768 case WSAENETDOWN: return "Network is down";
769 case WSAECONNREFUSED: return "Connection refused";
770 case WSAENETUNREACH: return "Network is unreachable";
771 case WSAEHOSTUNREACH: return "No route to host";
772 default: return "connect(): unknown error";
776 send(s, "connect ", 8, 0);
777 send(s, FWhost, strlen(FWhost), 0);
780 sprintf(buf, " %d\n", FWport);
781 send (s, buf, strlen(buf), 0);
788 static int ssh_versioncmp(char *a, char *b) {
790 unsigned long av, bv;
792 av = strtoul(a, &ae, 10);
793 bv = strtoul(b, &be, 10);
794 if (av != bv) return (av < bv ? -1 : +1);
795 if (*ae == '.') ae++;
796 if (*be == '.') be++;
797 av = strtoul(ae, &ae, 10);
798 bv = strtoul(be, &be, 10);
799 if (av != bv) return (av < bv ? -1 : +1);
805 * Utility routine for putting an SSH-protocol `string' into a SHA
809 void sha_string(SHA_State *s, void *str, int len) {
810 unsigned char lenblk[4];
811 PUT_32BIT(lenblk, len);
812 SHA_Bytes(s, lenblk, 4);
813 SHA_Bytes(s, str, len);
817 * SSH2 packet construction functions.
819 void ssh2_pkt_adddata(void *data, int len) {
820 pktout.length += len;
821 if (pktout.maxlen < pktout.length) {
822 pktout.maxlen = pktout.length + 256;
823 pktout.data = (pktout.data == NULL ? malloc(pktout.maxlen+APIEXTRA) :
824 realloc(pktout.data, pktout.maxlen+APIEXTRA));
826 fatalbox("Out of memory");
828 memcpy(pktout.data+pktout.length-len, data, len);
830 void ssh2_pkt_addbyte(unsigned char byte) {
831 ssh2_pkt_adddata(&byte, 1);
833 void ssh2_pkt_init(int pkt_type) {
835 ssh2_pkt_addbyte((unsigned char)pkt_type);
837 void ssh2_pkt_addbool(unsigned char value) {
838 ssh2_pkt_adddata(&value, 1);
840 void ssh2_pkt_adduint32(unsigned long value) {
843 ssh2_pkt_adddata(x, 4);
845 void ssh2_pkt_addstring_start(void) {
846 ssh2_pkt_adduint32(0);
847 pktout.savedpos = pktout.length;
849 void ssh2_pkt_addstring_str(char *data) {
850 ssh2_pkt_adddata(data, strlen(data));
851 PUT_32BIT(pktout.data + pktout.savedpos - 4,
852 pktout.length - pktout.savedpos);
854 void ssh2_pkt_addstring_data(char *data, int len) {
855 ssh2_pkt_adddata(data, len);
856 PUT_32BIT(pktout.data + pktout.savedpos - 4,
857 pktout.length - pktout.savedpos);
859 void ssh2_pkt_addstring(char *data) {
860 ssh2_pkt_addstring_start();
861 ssh2_pkt_addstring_str(data);
863 char *ssh2_mpint_fmt(Bignum b, int *len) {
866 p = malloc(n * 2 + 1);
868 fatalbox("out of memory");
870 for (i = 0; i < n; i++) {
871 p[i*2+1] = (b[n-i] >> 8) & 0xFF;
872 p[i*2+2] = (b[n-i] ) & 0xFF;
875 while (p[i] == 0 && (p[i+1] & 0x80) == 0)
877 memmove(p, p+i, n*2+1-i);
881 void ssh2_pkt_addmp(Bignum b) {
884 p = ssh2_mpint_fmt(b, &len);
885 ssh2_pkt_addstring_start();
886 ssh2_pkt_addstring_data(p, len);
889 void ssh2_pkt_send(void) {
890 int cipherblk, maclen, padding, i;
891 static unsigned long outgoing_sequence = 0;
894 * Add padding. At least four bytes, and must also bring total
895 * length (minus MAC) up to a multiple of the block size.
897 cipherblk = cipher ? cipher->blksize : 8; /* block size */
898 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
900 padding += (cipherblk - (pktout.length + padding) % cipherblk) % cipherblk;
901 pktout.data[4] = padding;
902 for (i = 0; i < padding; i++)
903 pktout.data[pktout.length + i] = random_byte();
904 PUT_32BIT(pktout.data, pktout.length + padding - 4);
906 csmac->generate(pktout.data, pktout.length + padding,
908 outgoing_sequence++; /* whether or not we MACed */
911 debug(("Sending packet len=%d\r\n", pktout.length+padding));
912 for (i = 0; i < pktout.length+padding; i++)
913 debug((" %02x", (unsigned char)pktout.data[i]));
918 cscipher->encrypt(pktout.data, pktout.length + padding);
919 maclen = csmac ? csmac->len : 0;
921 s_write(pktout.data, pktout.length + padding + maclen);
925 void bndebug(char *string, Bignum b) {
928 p = ssh2_mpint_fmt(b, &len);
929 debug(("%s", string));
930 for (i = 0; i < len; i++)
931 debug((" %02x", p[i]));
937 void sha_mpint(SHA_State *s, Bignum b) {
940 p = ssh2_mpint_fmt(b, &len);
941 sha_string(s, p, len);
946 * SSH2 packet decode functions.
948 unsigned long ssh2_pkt_getuint32(void) {
950 if (pktin.length - pktin.savedpos < 4)
951 return 0; /* arrgh, no way to decline (FIXME?) */
952 value = GET_32BIT(pktin.data+pktin.savedpos);
956 void ssh2_pkt_getstring(char **p, int *length) {
958 if (pktin.length - pktin.savedpos < 4)
960 *length = GET_32BIT(pktin.data+pktin.savedpos);
962 if (pktin.length - pktin.savedpos < *length)
964 *p = pktin.data+pktin.savedpos;
965 pktin.savedpos += *length;
967 Bignum ssh2_pkt_getmp(void) {
972 ssh2_pkt_getstring(&p, &length);
976 bombout(("internal error: Can't handle negative mpints"));
979 b = newbn((length+1)/2);
980 for (i = 0; i < length; i++) {
983 b[j/2+1] |= ((unsigned char)p[i]) << 8;
985 b[j/2+1] |= ((unsigned char)p[i]);
990 static int do_ssh_init(void) {
994 char vlog[sizeof(vstring)+20];
999 while (s_read(&c, 1) == 1) {
1000 if (c == 'S' && i < 2) i++;
1001 else if (c == 'S' && i == 2) i = 2;
1002 else if (c == 'H' && i == 2) break;
1006 if (s_read(&c,1) != 1 || c != 'S') return 0;
1007 if (s_read(&c,1) != 1 || c != 'S') return 0;
1008 if (s_read(&c,1) != 1 || c != 'H') return 0;
1010 strcpy(vstring, "SSH-");
1012 if (s_read(&c,1) != 1 || c != '-') return 0;
1015 if (s_read(&c,1) != 1)
1017 if (vsp < vstring+sizeof(vstring)-1)
1023 } else if (i < sizeof(version)-1)
1031 sprintf(vlog, "Server version: %s", vstring);
1032 vlog[strcspn(vlog, "\r\n")] = '\0';
1036 * Server version "1.99" means we can choose whether we use v1
1037 * or v2 protocol. Choice is based on cfg.sshprot.
1039 if (ssh_versioncmp(version, cfg.sshprot == 1 ? "2.0" : "1.99") >= 0) {
1041 * This is a v2 server. Begin v2 protocol.
1043 char *verstring = "SSH-2.0-PuTTY";
1046 * Hash our version string and their version string.
1048 sha_string(&exhash, verstring, strlen(verstring));
1049 sha_string(&exhash, vstring, strcspn(vstring, "\r\n"));
1050 sprintf(vstring, "%s\n", verstring);
1051 sprintf(vlog, "We claim version: %s", verstring);
1053 logevent("Using SSH protocol version 2");
1054 s_write(vstring, strlen(vstring));
1055 ssh_protocol = ssh2_protocol;
1057 s_rdpkt = ssh2_rdpkt;
1060 * This is a v1 server. Begin v1 protocol.
1062 sprintf(vstring, "SSH-%s-PuTTY\n",
1063 (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5"));
1064 sprintf(vlog, "We claim version: %s", vstring);
1065 vlog[strcspn(vlog, "\r\n")] = '\0';
1067 logevent("Using SSH protocol version 1");
1068 s_write(vstring, strlen(vstring));
1069 ssh_protocol = ssh1_protocol;
1071 s_rdpkt = ssh1_rdpkt;
1078 * Handle the key exchange and user authentication phases.
1080 static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
1083 unsigned char *rsabuf, *keystr1, *keystr2;
1084 unsigned char cookie[8];
1085 struct RSAKey servkey, hostkey;
1086 struct MD5Context md5c;
1087 static unsigned long supported_ciphers_mask, supported_auths_mask;
1088 static int tried_publickey;
1089 static unsigned char session_id[16];
1094 if (!ispkt) crWaitUntil(ispkt);
1096 if (pktin.type != SSH1_SMSG_PUBLIC_KEY) {
1097 bombout(("Public key packet not received"));
1101 logevent("Received public keys");
1103 memcpy(cookie, pktin.body, 8);
1105 i = makekey(pktin.body+8, &servkey, &keystr1, 0);
1106 j = makekey(pktin.body+8+i, &hostkey, &keystr2, 0);
1109 * Log the host key fingerprint.
1113 logevent("Host key fingerprint is:");
1114 strcpy(logmsg, " ");
1115 hostkey.comment = NULL;
1116 rsa_fingerprint(logmsg+strlen(logmsg), sizeof(logmsg)-strlen(logmsg),
1121 supported_ciphers_mask = GET_32BIT(pktin.body+12+i+j);
1122 supported_auths_mask = GET_32BIT(pktin.body+16+i+j);
1125 MD5Update(&md5c, keystr2, hostkey.bytes);
1126 MD5Update(&md5c, keystr1, servkey.bytes);
1127 MD5Update(&md5c, pktin.body, 8);
1128 MD5Final(session_id, &md5c);
1130 for (i=0; i<32; i++)
1131 session_key[i] = random_byte();
1133 len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
1135 rsabuf = malloc(len);
1137 fatalbox("Out of memory");
1140 * Verify the host key.
1144 * First format the key into a string.
1146 int len = rsastr_len(&hostkey);
1147 char fingerprint[100];
1148 char *keystr = malloc(len);
1150 fatalbox("Out of memory");
1151 rsastr_fmt(keystr, &hostkey);
1152 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
1153 verify_ssh_host_key(savedhost, savedport, "rsa", keystr, fingerprint);
1157 for (i=0; i<32; i++) {
1158 rsabuf[i] = session_key[i];
1160 rsabuf[i] ^= session_id[i];
1163 if (hostkey.bytes > servkey.bytes) {
1164 rsaencrypt(rsabuf, 32, &servkey);
1165 rsaencrypt(rsabuf, servkey.bytes, &hostkey);
1167 rsaencrypt(rsabuf, 32, &hostkey);
1168 rsaencrypt(rsabuf, hostkey.bytes, &servkey);
1171 logevent("Encrypted session key");
1173 cipher_type = cfg.cipher == CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH :
1174 cfg.cipher == CIPHER_DES ? SSH_CIPHER_DES :
1176 if ((supported_ciphers_mask & (1 << cipher_type)) == 0) {
1177 c_write("Selected cipher not supported, falling back to 3DES\r\n", 53);
1178 cipher_type = SSH_CIPHER_3DES;
1180 switch (cipher_type) {
1181 case SSH_CIPHER_3DES: logevent("Using 3DES encryption"); break;
1182 case SSH_CIPHER_DES: logevent("Using single-DES encryption"); break;
1183 case SSH_CIPHER_BLOWFISH: logevent("Using Blowfish encryption"); break;
1186 send_packet(SSH1_CMSG_SESSION_KEY,
1187 PKT_CHAR, cipher_type,
1188 PKT_DATA, cookie, 8,
1189 PKT_CHAR, (len*8) >> 8, PKT_CHAR, (len*8) & 0xFF,
1190 PKT_DATA, rsabuf, len,
1194 logevent("Trying to enable encryption...");
1198 cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
1199 cipher_type == SSH_CIPHER_DES ? &ssh_des :
1201 cipher->sesskey(session_key);
1205 if (pktin.type != SSH1_SMSG_SUCCESS) {
1206 bombout(("Encryption not successfully enabled"));
1210 logevent("Successfully started encryption");
1214 static char username[100];
1217 if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
1218 c_write("login as: ", 10);
1221 crWaitUntil(!ispkt);
1222 while (inlen--) switch (c = *in++) {
1229 c_write("\b \b", 3);
1235 c_write("\b \b", 3);
1244 if (((c >= ' ' && c <= '~') ||
1245 ((unsigned char)c >= 160)) && pos < 40) {
1246 username[pos++] = c;
1253 username[strcspn(username, "\n\r")] = '\0';
1256 strncpy(username, cfg.username, 99);
1257 username[99] = '\0';
1258 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
1259 sprintf(stuff, "Sent username \"%s\".\r\n", username);
1260 c_write(stuff, strlen(stuff));
1264 send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END);
1266 char userlog[20+sizeof(username)];
1267 sprintf(userlog, "Sent username \"%s\"", username);
1274 tried_publickey = 0;
1276 while (pktin.type == SSH1_SMSG_FAILURE) {
1277 static char password[100];
1278 static char prompt[200];
1281 static int pwpkt_type;
1283 * Show password prompt, having first obtained it via a TIS
1284 * or CryptoCard exchange if we're doing TIS or CryptoCard
1287 pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
1288 if (agent_exists()) {
1290 * Attempt RSA authentication using Pageant.
1292 static unsigned char request[5], *response, *p;
1293 static int responselen;
1294 static int i, nkeys;
1295 static int authed = FALSE;
1298 logevent("Pageant is running. Requesting keys.");
1300 /* Request the keys held by the agent. */
1301 PUT_32BIT(request, 1);
1302 request[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES;
1303 agent_query(request, 5, &r, &responselen);
1304 response = (unsigned char *)r;
1307 nkeys = GET_32BIT(p); p += 4;
1308 { char buf[64]; sprintf(buf, "Pageant has %d keys", nkeys);
1310 for (i = 0; i < nkeys; i++) {
1311 static struct RSAKey key;
1312 static Bignum challenge;
1313 static char *commentp;
1314 static int commentlen;
1316 { char buf[64]; sprintf(buf, "Trying Pageant key #%d", i);
1319 p += ssh1_read_bignum(p, &key.exponent);
1320 p += ssh1_read_bignum(p, &key.modulus);
1321 commentlen = GET_32BIT(p); p += 4;
1322 commentp = p; p += commentlen;
1323 send_packet(SSH1_CMSG_AUTH_RSA,
1324 PKT_BIGNUM, key.modulus, PKT_END);
1326 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
1327 logevent("Key refused");
1330 logevent("Received RSA challenge");
1331 ssh1_read_bignum(pktin.body, &challenge);
1333 char *agentreq, *q, *ret;
1335 len = 1 + 4; /* message type, bit count */
1336 len += ssh1_bignum_length(key.exponent);
1337 len += ssh1_bignum_length(key.modulus);
1338 len += ssh1_bignum_length(challenge);
1339 len += 16; /* session id */
1340 len += 4; /* response format */
1341 agentreq = malloc(4 + len);
1342 PUT_32BIT(agentreq, len);
1344 *q++ = SSH_AGENTC_RSA_CHALLENGE;
1345 PUT_32BIT(q, ssh1_bignum_bitcount(key.modulus));
1347 q += ssh1_write_bignum(q, key.exponent);
1348 q += ssh1_write_bignum(q, key.modulus);
1349 q += ssh1_write_bignum(q, challenge);
1350 memcpy(q, session_id, 16); q += 16;
1351 PUT_32BIT(q, 1); /* response format */
1352 agent_query(agentreq, len+4, &ret, &retlen);
1355 if (ret[4] == SSH_AGENT_RSA_RESPONSE) {
1356 logevent("Sending Pageant's response");
1357 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
1358 PKT_DATA, ret+5, 16, PKT_END);
1361 if (pktin.type == SSH1_SMSG_SUCCESS) {
1362 logevent("Pageant's response accepted");
1363 if (flags & FLAG_VERBOSE) {
1364 c_write("Authenticated using RSA key \"",
1366 c_write(commentp, commentlen);
1367 c_write("\" from agent\r\n", 14);
1371 logevent("Pageant's response not accepted");
1373 logevent("Pageant failed to answer challenge");
1377 logevent("No reply received from Pageant");
1380 freebn(key.exponent);
1381 freebn(key.modulus);
1390 if (*cfg.keyfile && !tried_publickey)
1391 pwpkt_type = SSH1_CMSG_AUTH_RSA;
1393 if (pktin.type == SSH1_SMSG_FAILURE &&
1395 (supported_auths_mask & (1<<SSH1_AUTH_TIS))) {
1396 pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
1397 logevent("Requested TIS authentication");
1398 send_packet(SSH1_CMSG_AUTH_TIS, PKT_END);
1400 if (pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
1401 logevent("TIS authentication declined");
1402 if (flags & FLAG_INTERACTIVE)
1403 c_write("TIS authentication refused.\r\n", 29);
1405 int challengelen = ((pktin.body[0] << 24) |
1406 (pktin.body[1] << 16) |
1407 (pktin.body[2] << 8) |
1409 logevent("Received TIS challenge");
1410 if (challengelen > sizeof(prompt)-1)
1411 challengelen = sizeof(prompt)-1; /* prevent overrun */
1412 memcpy(prompt, pktin.body+4, challengelen);
1413 prompt[challengelen] = '\0';
1416 if (pktin.type == SSH1_SMSG_FAILURE &&
1418 (supported_auths_mask & (1<<SSH1_AUTH_CCARD))) {
1419 pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
1420 logevent("Requested CryptoCard authentication");
1421 send_packet(SSH1_CMSG_AUTH_CCARD, PKT_END);
1423 if (pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
1424 logevent("CryptoCard authentication declined");
1425 c_write("CryptoCard authentication refused.\r\n", 29);
1427 int challengelen = ((pktin.body[0] << 24) |
1428 (pktin.body[1] << 16) |
1429 (pktin.body[2] << 8) |
1431 logevent("Received CryptoCard challenge");
1432 if (challengelen > sizeof(prompt)-1)
1433 challengelen = sizeof(prompt)-1; /* prevent overrun */
1434 memcpy(prompt, pktin.body+4, challengelen);
1435 strncpy(prompt + challengelen, "\r\nResponse : ",
1436 sizeof(prompt)-challengelen);
1437 prompt[sizeof(prompt)-1] = '\0';
1440 if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
1441 sprintf(prompt, "%.90s@%.90s's password: ",
1442 cfg.username, savedhost);
1444 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
1445 char *comment = NULL;
1446 if (flags & FLAG_VERBOSE)
1447 c_write("Trying public key authentication.\r\n", 35);
1448 if (!rsakey_encrypted(cfg.keyfile, &comment)) {
1449 if (flags & FLAG_VERBOSE)
1450 c_write("No passphrase required.\r\n", 25);
1453 sprintf(prompt, "Passphrase for key \"%.100s\": ", comment);
1457 if (!(flags & FLAG_INTERACTIVE)) {
1458 if (!ssh_get_password(prompt, password, sizeof(password))) {
1460 * get_password failed to get a password (for
1461 * example because one was supplied on the command
1462 * line which has already failed to work).
1465 logevent("No more passwords to try");
1466 ssh_state = SSH_STATE_CLOSED;
1470 c_write(prompt, strlen(prompt));
1474 crWaitUntil(!ispkt);
1475 while (inlen--) switch (c = *in++) {
1492 if (((c >= ' ' && c <= '~') ||
1493 ((unsigned char)c >= 160)) && pos < sizeof(password))
1494 password[pos++] = c;
1502 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
1504 * Try public key authentication with the specified
1507 static struct RSAKey pubkey;
1508 static Bignum challenge, response;
1510 static unsigned char buffer[32];
1512 tried_publickey = 1;
1513 i = loadrsakey(cfg.keyfile, &pubkey, password);
1515 c_write("Couldn't load public key from ", 30);
1516 c_write(cfg.keyfile, strlen(cfg.keyfile));
1517 c_write(".\r\n", 3);
1518 continue; /* go and try password */
1521 c_write("Wrong passphrase.\r\n", 19);
1522 tried_publickey = 0;
1523 continue; /* try again */
1527 * Send a public key attempt.
1529 send_packet(SSH1_CMSG_AUTH_RSA,
1530 PKT_BIGNUM, pubkey.modulus, PKT_END);
1533 if (pktin.type == SSH1_SMSG_FAILURE) {
1534 c_write("Server refused our public key.\r\n", 32);
1535 continue; /* go and try password */
1537 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
1538 bombout(("Bizarre response to offer of public key"));
1541 ssh1_read_bignum(pktin.body, &challenge);
1542 response = rsadecrypt(challenge, &pubkey);
1543 freebn(pubkey.private_exponent); /* burn the evidence */
1545 for (i = 0; i < 32; i += 2) {
1546 buffer[i] = response[16-i/2] >> 8;
1547 buffer[i+1] = response[16-i/2] & 0xFF;
1551 MD5Update(&md5c, buffer, 32);
1552 MD5Update(&md5c, session_id, 16);
1553 MD5Final(buffer, &md5c);
1555 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
1556 PKT_DATA, buffer, 16, PKT_END);
1559 if (pktin.type == SSH1_SMSG_FAILURE) {
1560 if (flags & FLAG_VERBOSE)
1561 c_write("Failed to authenticate with our public key.\r\n",
1563 continue; /* go and try password */
1564 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
1565 bombout(("Bizarre response to RSA authentication response"));
1569 break; /* we're through! */
1571 send_packet(pwpkt_type, PKT_STR, password, PKT_END);
1573 logevent("Sent password");
1574 memset(password, 0, strlen(password));
1576 if (pktin.type == SSH1_SMSG_FAILURE) {
1577 if (flags & FLAG_VERBOSE)
1578 c_write("Access denied\r\n", 15);
1579 logevent("Authentication refused");
1580 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
1581 logevent("Received disconnect request");
1582 ssh_state = SSH_STATE_CLOSED;
1584 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
1585 bombout(("Strange packet received, type %d", pktin.type));
1590 logevent("Authentication successful");
1595 static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) {
1600 while (!do_ssh1_login(in, inlen, ispkt)) {
1603 if (ssh_state == SSH_STATE_CLOSED)
1606 if (cfg.agentfwd && agent_exists()) {
1607 logevent("Requesting agent forwarding");
1608 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
1609 do { crReturnV; } while (!ispkt);
1610 if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
1611 bombout(("Protocol confusion"));
1613 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1614 logevent("Agent forwarding refused");
1616 logevent("Agent forwarding enabled");
1620 send_packet(SSH1_CMSG_REQUEST_PTY,
1621 PKT_STR, cfg.termtype,
1622 PKT_INT, rows, PKT_INT, cols,
1623 PKT_INT, 0, PKT_INT, 0,
1626 ssh_state = SSH_STATE_INTERMED;
1627 do { crReturnV; } while (!ispkt);
1628 if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
1629 bombout(("Protocol confusion"));
1631 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1632 c_write("Server refused to allocate pty\r\n", 32);
1634 logevent("Allocated pty");
1637 if (*cfg.remote_cmd)
1638 send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cfg.remote_cmd, PKT_END);
1640 send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END);
1641 logevent("Started session");
1643 ssh_state = SSH_STATE_SESSION;
1648 ssh_channels = newtree234(ssh_channelcmp);
1653 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
1654 pktin.type == SSH1_SMSG_STDERR_DATA) {
1655 long len = GET_32BIT(pktin.body);
1656 c_writedata(pktin.body+4, len);
1657 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
1658 ssh_state = SSH_STATE_CLOSED;
1659 logevent("Received disconnect request");
1660 } else if (pktin.type == SSH1_SMSG_AGENT_OPEN) {
1661 /* Remote side is trying to open a channel to talk to our
1662 * agent. Give them back a local channel number. */
1664 struct ssh_channel *c;
1666 for (c = first234(ssh_channels, &e); c; c = next234(&e)) {
1668 break; /* found a free number */
1671 c = malloc(sizeof(struct ssh_channel));
1672 c->remoteid = GET_32BIT(pktin.body);
1675 c->type = SSH1_SMSG_AGENT_OPEN; /* identify channel type */
1676 c->u.a.lensofar = 0;
1677 add234(ssh_channels, c);
1678 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
1679 PKT_INT, c->remoteid, PKT_INT, c->localid,
1681 } else if (pktin.type == SSH1_MSG_CHANNEL_CLOSE ||
1682 pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
1683 /* Remote side closes a channel. */
1684 unsigned i = GET_32BIT(pktin.body);
1685 struct ssh_channel *c;
1686 c = find234(ssh_channels, &i, ssh_channelfind);
1689 closetype = (pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
1690 send_packet(pktin.type, PKT_INT, c->remoteid, PKT_END);
1691 c->closes |= closetype;
1692 if (c->closes == 3) {
1693 del234(ssh_channels, c);
1697 } else if (pktin.type == SSH1_MSG_CHANNEL_DATA) {
1698 /* Data sent down one of our channels. */
1699 int i = GET_32BIT(pktin.body);
1700 int len = GET_32BIT(pktin.body+4);
1701 unsigned char *p = pktin.body+8;
1702 struct ssh_channel *c;
1703 c = find234(ssh_channels, &i, ssh_channelfind);
1706 case SSH1_SMSG_AGENT_OPEN:
1707 /* Data for an agent message. Buffer it. */
1709 if (c->u.a.lensofar < 4) {
1710 int l = min(4 - c->u.a.lensofar, len);
1711 memcpy(c->u.a.msglen + c->u.a.lensofar, p, l);
1712 p += l; len -= l; c->u.a.lensofar += l;
1714 if (c->u.a.lensofar == 4) {
1715 c->u.a.totallen = 4 + GET_32BIT(c->u.a.msglen);
1716 c->u.a.message = malloc(c->u.a.totallen);
1717 memcpy(c->u.a.message, c->u.a.msglen, 4);
1719 if (c->u.a.lensofar >= 4 && len > 0) {
1720 int l = min(c->u.a.totallen - c->u.a.lensofar, len);
1721 memcpy(c->u.a.message + c->u.a.lensofar, p, l);
1722 p += l; len -= l; c->u.a.lensofar += l;
1724 if (c->u.a.lensofar == c->u.a.totallen) {
1725 void *reply, *sentreply;
1727 agent_query(c->u.a.message, c->u.a.totallen,
1732 /* Fake SSH_AGENT_FAILURE. */
1733 sentreply = "\0\0\0\1\5";
1736 send_packet(SSH1_MSG_CHANNEL_DATA,
1737 PKT_INT, c->remoteid,
1739 PKT_DATA, sentreply, replylen,
1743 free(c->u.a.message);
1744 c->u.a.lensofar = 0;
1750 } else if (pktin.type == SSH1_SMSG_SUCCESS) {
1751 /* may be from EXEC_SHELL on some servers */
1752 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1753 /* may be from EXEC_SHELL on some servers
1754 * if no pty is available or in other odd cases. Ignore */
1755 } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) {
1756 send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
1758 bombout(("Strange packet received: type %d", pktin.type));
1762 send_packet(SSH1_CMSG_STDIN_DATA,
1763 PKT_INT, inlen, PKT_DATA, in, inlen, PKT_END);
1771 * Utility routine for decoding comma-separated strings in KEXINIT.
1773 int in_commasep_string(char *needle, char *haystack, int haylen) {
1774 int needlen = strlen(needle);
1777 * Is it at the start of the string?
1779 if (haylen >= needlen && /* haystack is long enough */
1780 !memcmp(needle, haystack, needlen) && /* initial match */
1781 (haylen == needlen || haystack[needlen] == ',')
1782 /* either , or EOS follows */
1786 * If not, search for the next comma and resume after that.
1787 * If no comma found, terminate.
1789 while (haylen > 0 && *haystack != ',')
1790 haylen--, haystack++;
1793 haylen--, haystack++; /* skip over comma itself */
1798 * SSH2 key creation method.
1800 void ssh2_mkkey(Bignum K, char *H, char chr, char *keyspace) {
1802 /* First 20 bytes. */
1805 SHA_Bytes(&s, H, 20);
1806 SHA_Bytes(&s, &chr, 1);
1807 SHA_Bytes(&s, H, 20);
1808 SHA_Final(&s, keyspace);
1809 /* Next 20 bytes. */
1812 SHA_Bytes(&s, H, 20);
1813 SHA_Bytes(&s, keyspace, 20);
1814 SHA_Final(&s, keyspace+20);
1818 * Handle the SSH2 transport layer.
1820 static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt)
1824 static Bignum e, f, K;
1825 static struct ssh_cipher *cscipher_tobe = NULL;
1826 static struct ssh_cipher *sccipher_tobe = NULL;
1827 static struct ssh_mac *csmac_tobe = NULL;
1828 static struct ssh_mac *scmac_tobe = NULL;
1829 static struct ssh_compress *cscomp_tobe = NULL;
1830 static 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];
1840 * Set up the preferred cipher.
1842 if (cfg.cipher == CIPHER_BLOWFISH) {
1843 ciphers[0] = &ssh_blowfish_ssh2;
1844 } else if (cfg.cipher == CIPHER_DES) {
1845 logevent("Single DES not supported in SSH2; using 3DES");
1846 ciphers[0] = &ssh_3des_ssh2;
1847 } else if (cfg.cipher == CIPHER_3DES) {
1848 ciphers[0] = &ssh_3des_ssh2;
1850 /* Shouldn't happen, but we do want to initialise to _something_. */
1851 ciphers[0] = &ssh_3des_ssh2;
1856 * Construct and send our key exchange packet.
1858 ssh2_pkt_init(SSH2_MSG_KEXINIT);
1859 for (i = 0; i < 16; i++)
1860 ssh2_pkt_addbyte((unsigned char)random_byte());
1861 /* List key exchange algorithms. */
1862 ssh2_pkt_addstring_start();
1863 for (i = 0; i < lenof(kex_algs); i++) {
1864 ssh2_pkt_addstring_str(kex_algs[i]->name);
1865 if (i < lenof(kex_algs)-1)
1866 ssh2_pkt_addstring_str(",");
1868 /* List server host key algorithms. */
1869 ssh2_pkt_addstring_start();
1870 for (i = 0; i < lenof(hostkey_algs); i++) {
1871 ssh2_pkt_addstring_str(hostkey_algs[i]->name);
1872 if (i < lenof(hostkey_algs)-1)
1873 ssh2_pkt_addstring_str(",");
1875 /* List client->server encryption algorithms. */
1876 ssh2_pkt_addstring_start();
1877 for (i = 0; i < lenof(ciphers); i++) {
1878 ssh2_pkt_addstring_str(ciphers[i]->name);
1879 if (i < lenof(ciphers)-1)
1880 ssh2_pkt_addstring_str(",");
1882 /* List server->client encryption algorithms. */
1883 ssh2_pkt_addstring_start();
1884 for (i = 0; i < lenof(ciphers); i++) {
1885 ssh2_pkt_addstring_str(ciphers[i]->name);
1886 if (i < lenof(ciphers)-1)
1887 ssh2_pkt_addstring_str(",");
1889 /* List client->server MAC algorithms. */
1890 ssh2_pkt_addstring_start();
1891 for (i = 0; i < lenof(macs); i++) {
1892 ssh2_pkt_addstring_str(macs[i]->name);
1893 if (i < lenof(macs)-1)
1894 ssh2_pkt_addstring_str(",");
1896 /* List server->client MAC algorithms. */
1897 ssh2_pkt_addstring_start();
1898 for (i = 0; i < lenof(macs); i++) {
1899 ssh2_pkt_addstring_str(macs[i]->name);
1900 if (i < lenof(macs)-1)
1901 ssh2_pkt_addstring_str(",");
1903 /* List client->server compression algorithms. */
1904 ssh2_pkt_addstring_start();
1905 for (i = 0; i < lenof(compressions); i++) {
1906 ssh2_pkt_addstring_str(compressions[i]->name);
1907 if (i < lenof(compressions)-1)
1908 ssh2_pkt_addstring_str(",");
1910 /* List server->client compression algorithms. */
1911 ssh2_pkt_addstring_start();
1912 for (i = 0; i < lenof(compressions); i++) {
1913 ssh2_pkt_addstring_str(compressions[i]->name);
1914 if (i < lenof(compressions)-1)
1915 ssh2_pkt_addstring_str(",");
1917 /* List client->server languages. Empty list. */
1918 ssh2_pkt_addstring_start();
1919 /* List server->client languages. Empty list. */
1920 ssh2_pkt_addstring_start();
1921 /* First KEX packet does _not_ follow, because we're not that brave. */
1922 ssh2_pkt_addbool(FALSE);
1924 ssh2_pkt_adduint32(0);
1925 sha_string(&exhash, pktout.data+5, pktout.length-5);
1928 if (!ispkt) crWaitUntil(ispkt);
1929 sha_string(&exhash, pktin.data+5, pktin.length-5);
1932 * Now examine the other side's KEXINIT to see what we're up
1935 if (pktin.type != SSH2_MSG_KEXINIT) {
1936 bombout(("expected key exchange packet from server"));
1939 kex = NULL; hostkey = NULL; cscipher_tobe = NULL; sccipher_tobe = NULL;
1940 csmac_tobe = NULL; scmac_tobe = NULL; cscomp_tobe = NULL; sccomp_tobe = NULL;
1941 pktin.savedpos += 16; /* skip garbage cookie */
1942 ssh2_pkt_getstring(&str, &len); /* key exchange algorithms */
1943 for (i = 0; i < lenof(kex_algs); i++) {
1944 if (in_commasep_string(kex_algs[i]->name, str, len)) {
1949 ssh2_pkt_getstring(&str, &len); /* host key algorithms */
1950 for (i = 0; i < lenof(hostkey_algs); i++) {
1951 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
1952 hostkey = hostkey_algs[i];
1956 ssh2_pkt_getstring(&str, &len); /* client->server cipher */
1957 for (i = 0; i < lenof(ciphers); i++) {
1958 if (in_commasep_string(ciphers[i]->name, str, len)) {
1959 cscipher_tobe = ciphers[i];
1963 ssh2_pkt_getstring(&str, &len); /* server->client cipher */
1964 for (i = 0; i < lenof(ciphers); i++) {
1965 if (in_commasep_string(ciphers[i]->name, str, len)) {
1966 sccipher_tobe = ciphers[i];
1970 ssh2_pkt_getstring(&str, &len); /* client->server mac */
1971 for (i = 0; i < lenof(macs); i++) {
1972 if (in_commasep_string(macs[i]->name, str, len)) {
1973 csmac_tobe = macs[i];
1977 ssh2_pkt_getstring(&str, &len); /* server->client mac */
1978 for (i = 0; i < lenof(macs); i++) {
1979 if (in_commasep_string(macs[i]->name, str, len)) {
1980 scmac_tobe = macs[i];
1984 ssh2_pkt_getstring(&str, &len); /* client->server compression */
1985 for (i = 0; i < lenof(compressions); i++) {
1986 if (in_commasep_string(compressions[i]->name, str, len)) {
1987 cscomp_tobe = compressions[i];
1991 ssh2_pkt_getstring(&str, &len); /* server->client compression */
1992 for (i = 0; i < lenof(compressions); i++) {
1993 if (in_commasep_string(compressions[i]->name, str, len)) {
1994 sccomp_tobe = compressions[i];
2000 * Currently we only support Diffie-Hellman and DSS, so let's
2001 * bomb out if those aren't selected.
2003 if (kex != &ssh_diffiehellman || hostkey != &ssh_dss) {
2004 bombout(("internal fault: chaos in SSH 2 transport layer"));
2009 * Now we begin the fun. Generate and send e for Diffie-Hellman.
2012 ssh2_pkt_init(SSH2_MSG_KEXDH_INIT);
2017 if (pktin.type != SSH2_MSG_KEXDH_REPLY) {
2018 bombout(("expected key exchange packet from server"));
2021 ssh2_pkt_getstring(&hostkeydata, &hostkeylen);
2022 f = ssh2_pkt_getmp();
2023 ssh2_pkt_getstring(&sigdata, &siglen);
2027 sha_string(&exhash, hostkeydata, hostkeylen);
2028 sha_mpint(&exhash, e);
2029 sha_mpint(&exhash, f);
2030 sha_mpint(&exhash, K);
2031 SHA_Final(&exhash, exchange_hash);
2034 debug(("Exchange hash is:\r\n"));
2035 for (i = 0; i < 20; i++)
2036 debug((" %02x", exchange_hash[i]));
2040 hostkey->setkey(hostkeydata, hostkeylen);
2041 if (!hostkey->verifysig(sigdata, siglen, exchange_hash, 20)) {
2042 bombout(("Server failed host key check"));
2047 * Expect SSH2_MSG_NEWKEYS from server.
2050 if (pktin.type != SSH2_MSG_NEWKEYS) {
2051 bombout(("expected new-keys packet from server"));
2056 * Authenticate remote host: verify host key. (We've already
2057 * checked the signature of the exchange hash.)
2059 keystr = hostkey->fmtkey();
2060 fingerprint = hostkey->fingerprint();
2061 verify_ssh_host_key(savedhost, savedport, hostkey->keytype,
2062 keystr, fingerprint);
2063 logevent("Host key fingerprint is:");
2064 logevent(fingerprint);
2069 * Send SSH2_MSG_NEWKEYS.
2071 ssh2_pkt_init(SSH2_MSG_NEWKEYS);
2075 * Create and initialise session keys.
2077 cscipher = cscipher_tobe;
2078 sccipher = sccipher_tobe;
2081 cscomp = cscomp_tobe;
2082 sccomp = sccomp_tobe;
2084 * Set IVs after keys.
2086 ssh2_mkkey(K, exchange_hash, 'C', keyspace); cscipher->setcskey(keyspace);
2087 ssh2_mkkey(K, exchange_hash, 'D', keyspace); cscipher->setsckey(keyspace);
2088 ssh2_mkkey(K, exchange_hash, 'A', keyspace); cscipher->setcsiv(keyspace);
2089 ssh2_mkkey(K, exchange_hash, 'B', keyspace); sccipher->setsciv(keyspace);
2090 ssh2_mkkey(K, exchange_hash, 'E', keyspace); csmac->setcskey(keyspace);
2091 ssh2_mkkey(K, exchange_hash, 'F', keyspace); scmac->setsckey(keyspace);
2094 * Now we're encrypting. Begin returning 1 to the protocol main
2095 * function so that other things can run on top of the
2096 * transport. If we ever see a KEXINIT, we must go back to the
2101 } while (!(ispkt && pktin.type == SSH2_MSG_KEXINIT));
2102 goto begin_key_exchange;
2108 * Handle the SSH2 userauth and connection layers.
2110 static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
2112 static unsigned long remote_winsize;
2113 static unsigned long remote_maxpkt;
2118 * Request userauth protocol, and await a response to it.
2120 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
2121 ssh2_pkt_addstring("ssh-userauth");
2123 crWaitUntilV(ispkt);
2124 if (pktin.type != SSH2_MSG_SERVICE_ACCEPT) {
2125 bombout(("Server refused user authentication protocol"));
2130 * FIXME: currently we support only password authentication.
2131 * (This places us technically in violation of the SSH2 spec.
2132 * We must fix this.)
2136 * Get a username and a password.
2138 static char username[100];
2139 static char password[100];
2143 if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
2144 c_write("login as: ", 10);
2147 crWaitUntilV(!ispkt);
2148 while (inlen--) switch (c = *in++) {
2155 c_write("\b \b", 3);
2161 c_write("\b \b", 3);
2170 if (((c >= ' ' && c <= '~') ||
2171 ((unsigned char)c >= 160)) && pos < 40) {
2172 username[pos++] = c;
2179 username[strcspn(username, "\n\r")] = '\0';
2182 strncpy(username, cfg.username, 99);
2183 username[99] = '\0';
2184 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
2185 sprintf(stuff, "Using username \"%s\".\r\n", username);
2186 c_write(stuff, strlen(stuff));
2190 if (!(flags & FLAG_INTERACTIVE)) {
2192 sprintf(prompt, "%.90s@%.90s's password: ", cfg.username, savedhost);
2193 if (!ssh_get_password(prompt, password, sizeof(password))) {
2195 * get_password failed to get a password (for
2196 * example because one was supplied on the command
2197 * line which has already failed to work).
2200 logevent("No more passwords to try");
2201 ssh_state = SSH_STATE_CLOSED;
2205 c_write("password: ", 10);
2210 crWaitUntilV(!ispkt);
2211 while (inlen--) switch (c = *in++) {
2228 if (((c >= ' ' && c <= '~') ||
2229 ((unsigned char)c >= 160)) && pos < 40)
2230 password[pos++] = c;
2237 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
2238 ssh2_pkt_addstring(username);
2239 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2240 ssh2_pkt_addstring("password");
2241 ssh2_pkt_addbool(FALSE);
2242 ssh2_pkt_addstring(password);
2245 crWaitUntilV(ispkt);
2246 if (pktin.type != SSH2_MSG_USERAUTH_SUCCESS) {
2247 c_write("Access denied\r\n", 15);
2248 logevent("Authentication refused");
2254 * Now we're authenticated for the connection protocol. The
2255 * connection protocol will automatically have started at this
2256 * point; there's no need to send SERVICE_REQUEST.
2260 * So now create a channel with a session in it.
2262 mainchan = malloc(sizeof(struct ssh_channel));
2263 mainchan->localid = 100; /* as good as any */
2264 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
2265 ssh2_pkt_addstring("session");
2266 ssh2_pkt_adduint32(mainchan->localid);
2267 ssh2_pkt_adduint32(0x7FFFFFFFUL); /* our window size */
2268 ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
2270 crWaitUntilV(ispkt);
2271 if (pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
2272 bombout(("Server refused to open a session"));
2274 /* FIXME: error data comes back in FAILURE packet */
2276 if (ssh2_pkt_getuint32() != mainchan->localid) {
2277 bombout(("Server's channel confirmation cited wrong channel"));
2280 mainchan->remoteid = ssh2_pkt_getuint32();
2281 mainchan->u.v2.remwindow = ssh2_pkt_getuint32();
2282 mainchan->u.v2.remmaxpkt = ssh2_pkt_getuint32();
2283 mainchan->u.v2.outbuffer = NULL;
2284 mainchan->u.v2.outbuflen = mainchan->u.v2.outbufsize = 0;
2285 logevent("Opened channel for session");
2288 * Now allocate a pty for the session.
2291 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
2292 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
2293 ssh2_pkt_addstring("pty-req");
2294 ssh2_pkt_addbool(1); /* want reply */
2295 ssh2_pkt_addstring(cfg.termtype);
2296 ssh2_pkt_adduint32(cols);
2297 ssh2_pkt_adduint32(rows);
2298 ssh2_pkt_adduint32(0); /* pixel width */
2299 ssh2_pkt_adduint32(0); /* pixel height */
2300 ssh2_pkt_addstring_start();
2301 ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
2305 crWaitUntilV(ispkt);
2306 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2307 /* FIXME: be able to handle other channels here */
2308 if (ssh2_pkt_getuint32() != mainchan->localid)
2309 continue; /* wrong channel */
2310 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2312 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2314 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
2315 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
2316 bombout(("Server got confused by pty request"));
2319 c_write("Server refused to allocate pty\r\n", 32);
2321 logevent("Allocated pty");
2326 * Start a shell or a remote command.
2328 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
2329 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
2330 if (*cfg.remote_cmd) {
2331 ssh2_pkt_addstring("exec");
2332 ssh2_pkt_addbool(1); /* want reply */
2333 ssh2_pkt_addstring(cfg.remote_cmd);
2335 ssh2_pkt_addstring("shell");
2336 ssh2_pkt_addbool(1); /* want reply */
2340 crWaitUntilV(ispkt);
2341 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2342 /* FIXME: be able to handle other channels here */
2343 if (ssh2_pkt_getuint32() != mainchan->localid)
2344 continue; /* wrong channel */
2345 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2347 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2348 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
2349 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
2350 bombout(("Server got confused by shell/command request"));
2353 bombout(("Server refused to start a shell/command"));
2356 logevent("Started a shell/command");
2365 static int try_send;
2369 if (pktin.type == SSH2_MSG_CHANNEL_DATA ||
2370 pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
2373 /* FIXME: be able to handle other channels here */
2374 if (ssh2_pkt_getuint32() != mainchan->localid)
2375 continue; /* wrong channel */
2376 if (pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
2377 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR)
2378 continue; /* extended but not stderr */
2379 ssh2_pkt_getstring(&data, &length);
2381 c_writedata(data, length);
2383 * Enlarge the window again at the remote side,
2384 * just in case it ever runs down and they fail
2385 * to send us any more data.
2387 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2388 ssh2_pkt_adduint32(mainchan->remoteid);
2389 ssh2_pkt_adduint32(length);
2392 } else if (pktin.type == SSH2_MSG_DISCONNECT) {
2393 ssh_state = SSH_STATE_CLOSED;
2394 logevent("Received disconnect message");
2395 } else if (pktin.type == SSH2_MSG_CHANNEL_REQUEST) {
2396 continue; /* exit status et al; ignore (FIXME?) */
2397 } else if (pktin.type == SSH2_MSG_CHANNEL_EOF) {
2398 continue; /* remote sends EOF; ignore */
2399 } else if (pktin.type == SSH2_MSG_CHANNEL_CLOSE) {
2400 /* FIXME: be able to handle other channels here */
2401 if (ssh2_pkt_getuint32() != mainchan->localid)
2402 continue; /* wrong channel */
2403 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
2404 ssh2_pkt_adduint32(mainchan->remoteid);
2406 /* FIXME: mark the channel as closed */
2407 if (1 /* FIXME: "all channels are closed" */) {
2408 logevent("All channels closed. Disconnecting");
2409 ssh2_pkt_init(SSH2_MSG_DISCONNECT);
2412 continue; /* remote sends close; ignore (FIXME) */
2413 } else if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2414 /* FIXME: be able to handle other channels here */
2415 if (ssh2_pkt_getuint32() != mainchan->localid)
2416 continue; /* wrong channel */
2417 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2420 bombout(("Strange packet received: type %d", pktin.type));
2425 * We have spare data. Add it to the channel buffer.
2427 if (mainchan->u.v2.outbufsize <
2428 mainchan->u.v2.outbuflen + inlen) {
2429 mainchan->u.v2.outbufsize =
2430 mainchan->u.v2.outbuflen + inlen + 1024;
2431 mainchan->u.v2.outbuffer = srealloc(mainchan->u.v2.outbuffer,
2432 mainchan->u.v2.outbufsize);
2434 memcpy(mainchan->u.v2.outbuffer + mainchan->u.v2.outbuflen,
2436 mainchan->u.v2.outbuflen += inlen;
2441 * Try to send data on the channel if we can. (FIXME:
2442 * on _all_ channels.)
2444 while (mainchan->u.v2.remwindow > 0 &&
2445 mainchan->u.v2.outbuflen > 0) {
2446 unsigned len = mainchan->u.v2.remwindow;
2447 if (len > mainchan->u.v2.outbuflen)
2448 len = mainchan->u.v2.outbuflen;
2449 if (len > mainchan->u.v2.remmaxpkt)
2450 len = mainchan->u.v2.remmaxpkt;
2451 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
2452 ssh2_pkt_adduint32(mainchan->remoteid);
2453 ssh2_pkt_addstring_start();
2454 ssh2_pkt_addstring_data(mainchan->u.v2.outbuffer, len);
2456 mainchan->u.v2.outbuflen -= len;
2457 memmove(mainchan->u.v2.outbuffer, mainchan->u.v2.outbuffer+len,
2458 mainchan->u.v2.outbuflen);
2459 mainchan->u.v2.remwindow -= len;
2468 * Handle the top-level SSH2 protocol.
2470 static void ssh2_protocol(unsigned char *in, int inlen, int ispkt)
2472 if (do_ssh2_transport(in, inlen, ispkt) == 0)
2474 do_ssh2_authconn(in, inlen, ispkt);
2478 * Called to set up the connection. Will arrange for WM_NETEVENT
2479 * messages to be passed to the specified window, whose window
2480 * procedure should then call telnet_msg().
2482 * Returns an error message, or NULL on success.
2484 static char *ssh_init (HWND hwnd, char *host, int port, char **realhost) {
2488 if(crypto_startup() == 0)
2489 return "Microsoft high encryption pack not installed!";
2492 p = connect_to_host(host, port, realhost);
2497 return "Protocol initialisation error";
2499 if (hwnd && WSAAsyncSelect (s, hwnd, WM_NETEVENT, FD_READ | FD_CLOSE) == SOCKET_ERROR)
2500 switch (WSAGetLastError()) {
2501 case WSAENETDOWN: return "Network is down";
2502 default: return "WSAAsyncSelect(): unknown error";
2509 * Process a WM_NETEVENT message. Will return 0 if the connection
2510 * has closed, or <0 for a socket error.
2512 static int ssh_msg (WPARAM wParam, LPARAM lParam) {
2517 * Because reading less than the whole of the available pending
2518 * data can generate an FD_READ event, we need to allow for the
2519 * possibility that FD_READ may arrive with FD_CLOSE already in
2520 * the queue; so it's possible that we can get here even with s
2521 * invalid. If so, we return 1 and don't worry about it.
2523 if (s == INVALID_SOCKET)
2526 if (WSAGETSELECTERROR(lParam) != 0) {
2529 return -WSAGETSELECTERROR(lParam);
2532 switch (WSAGETSELECTEVENT(lParam)) {
2535 ret = recv(s, buf, sizeof(buf), 0);
2536 if (ret < 0 && WSAGetLastError() == WSAEWOULDBLOCK)
2538 if (ret < 0) { /* any _other_ error */
2541 return -10000-WSAGetLastError();
2547 ssh_gotdata (buf, ret);
2548 if (ssh_state == SSH_STATE_CLOSED) {
2555 return 1; /* shouldn't happen, but WTF */
2559 * Called to send data down the Telnet connection.
2561 static void ssh_send (char *buf, int len) {
2562 if (s == INVALID_SOCKET)
2565 ssh_protocol(buf, len, 0);
2569 * Called to set the size of the window from Telnet's POV.
2571 static void ssh_size(void) {
2572 switch (ssh_state) {
2573 case SSH_STATE_BEFORE_SIZE:
2574 case SSH_STATE_CLOSED:
2575 break; /* do nothing */
2576 case SSH_STATE_INTERMED:
2577 size_needed = TRUE; /* buffer for later */
2579 case SSH_STATE_SESSION:
2581 send_packet(SSH1_CMSG_WINDOW_SIZE,
2582 PKT_INT, rows, PKT_INT, cols,
2583 PKT_INT, 0, PKT_INT, 0, PKT_END);
2589 * Send Telnet special codes. TS_EOF is useful for `plink', so you
2590 * can send an EOF and collect resulting output (e.g. `plink
2593 static void ssh_special (Telnet_Special code) {
2594 if (code == TS_EOF) {
2595 if (ssh_version == 1) {
2596 send_packet(SSH1_CMSG_EOF, PKT_END);
2598 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
2599 ssh2_pkt_adduint32(mainchan->remoteid);
2602 logevent("Sent EOF message");
2608 static SOCKET ssh_socket(void) { return s; }
2610 static int ssh_sendok(void) { return ssh_send_ok; }
2612 Backend ssh_backend = {