25 #define logevent(s) { logevent(s); \
26 if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \
27 fprintf(stderr, "%s\n", s); }
29 #define bombout(msg) ( ssh_state == SSH_STATE_CLOSED, closesocket(s), \
30 s = INVALID_SOCKET, connection_fatal msg )
32 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
33 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
34 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
35 #define SSH1_CMSG_USER 4 /* 0x4 */
36 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
37 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
38 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
39 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
40 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
41 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
42 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
43 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
44 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
45 #define SSH1_SMSG_FAILURE 15 /* 0xf */
46 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
47 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
48 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
49 #define SSH1_CMSG_EOF 19 /* 0x13 */
50 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
51 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
52 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
53 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
54 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
55 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
56 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
57 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
58 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
59 #define SSH1_MSG_IGNORE 32 /* 0x20 */
60 #define SSH1_MSG_DEBUG 36 /* 0x24 */
61 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
62 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
63 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
64 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
65 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
66 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
68 #define SSH1_AUTH_TIS 5 /* 0x5 */
69 #define SSH1_AUTH_CCARD 16 /* 0x10 */
71 #define SSH_AGENTC_REQUEST_RSA_IDENTITIES 1 /* 0x1 */
72 #define SSH_AGENT_RSA_IDENTITIES_ANSWER 2 /* 0x2 */
73 #define SSH_AGENTC_RSA_CHALLENGE 3 /* 0x3 */
74 #define SSH_AGENT_RSA_RESPONSE 4 /* 0x4 */
75 #define SSH_AGENT_FAILURE 5 /* 0x5 */
76 #define SSH_AGENT_SUCCESS 6 /* 0x6 */
77 #define SSH_AGENTC_ADD_RSA_IDENTITY 7 /* 0x7 */
78 #define SSH_AGENTC_REMOVE_RSA_IDENTITY 8 /* 0x8 */
80 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
81 #define SSH2_MSG_IGNORE 2 /* 0x2 */
82 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
83 #define SSH2_MSG_DEBUG 4 /* 0x4 */
84 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
85 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
86 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
87 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
88 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
89 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
90 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
91 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
92 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
93 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
94 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
95 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
96 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
97 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
98 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
99 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
100 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
101 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
102 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
103 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
104 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
105 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
106 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
107 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
108 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
109 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
111 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
112 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
113 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
114 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
116 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
118 #define GET_32BIT(cp) \
119 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
120 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
121 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
122 ((unsigned long)(unsigned char)(cp)[3]))
124 #define PUT_32BIT(cp, value) { \
125 (cp)[0] = (unsigned char)((value) >> 24); \
126 (cp)[1] = (unsigned char)((value) >> 16); \
127 (cp)[2] = (unsigned char)((value) >> 8); \
128 (cp)[3] = (unsigned char)(value); }
130 enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM };
132 /* Coroutine mechanics for the sillier bits of the code */
133 #define crBegin1 static int crLine = 0;
134 #define crBegin2 switch(crLine) { case 0:;
135 #define crBegin crBegin1; crBegin2;
136 #define crFinish(z) } crLine = 0; return (z)
137 #define crFinishV } crLine = 0; return
138 #define crReturn(z) \
140 crLine=__LINE__; return (z); case __LINE__:;\
144 crLine=__LINE__; return; case __LINE__:;\
146 #define crStop(z) do{ crLine = 0; return (z); }while(0)
147 #define crStopV do{ crLine = 0; return; }while(0)
148 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
149 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
151 extern struct ssh_cipher ssh_3des;
152 extern struct ssh_cipher ssh_3des_ssh2;
153 extern struct ssh_cipher ssh_des;
154 extern struct ssh_cipher ssh_blowfish_ssh1;
155 extern struct ssh_cipher ssh_blowfish_ssh2;
158 * Ciphers for SSH2. We miss out single-DES because it isn't
159 * supported; also 3DES and Blowfish are both done differently from
160 * SSH1. (3DES uses outer chaining; Blowfish has the opposite
161 * endianness and different-sized keys.)
163 * The first entry in this array is set up to be whatever the user
164 * asks for as a cipher. Thereafter there is a fixed preference
165 * order of fallback ciphers.
167 struct ssh_cipher *ciphers[] = { NULL, &ssh_blowfish_ssh2, &ssh_3des_ssh2 };
169 extern struct ssh_kex ssh_diffiehellman;
170 struct ssh_kex *kex_algs[] = { &ssh_diffiehellman };
172 extern struct ssh_hostkey ssh_dss;
173 struct ssh_hostkey *hostkey_algs[] = { &ssh_dss };
175 extern struct ssh_mac ssh_sha1;
177 static SHA_State exhash;
179 static void nullmac_key(unsigned char *key) { }
180 static void nullmac_generate(unsigned char *blk, int len, unsigned long seq) { }
181 static int nullmac_verify(unsigned char *blk, int len, unsigned long seq) { return 1; }
182 struct ssh_mac ssh_mac_none = {
183 nullmac_key, nullmac_key, nullmac_generate, nullmac_verify, "none", 0
185 struct ssh_mac *macs[] = { &ssh_sha1, &ssh_mac_none };
187 struct ssh_compress ssh_comp_none = {
190 struct ssh_compress *compressions[] = { &ssh_comp_none };
192 static SOCKET s = INVALID_SOCKET;
194 static unsigned char session_key[32];
195 static struct ssh_cipher *cipher = NULL;
196 static struct ssh_cipher *cscipher = NULL;
197 static struct ssh_cipher *sccipher = NULL;
198 static struct ssh_mac *csmac = NULL;
199 static struct ssh_mac *scmac = NULL;
200 static struct ssh_compress *cscomp = NULL;
201 static struct ssh_compress *sccomp = NULL;
202 static struct ssh_kex *kex = NULL;
203 static struct ssh_hostkey *hostkey = NULL;
204 int (*ssh_get_password)(const char *prompt, char *str, int maxlen) = NULL;
206 static char *savedhost;
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);
303 static struct Packet pktin = { 0, 0, NULL, NULL, 0 };
304 static struct Packet pktout = { 0, 0, NULL, NULL, 0 };
306 static int ssh_version;
307 static void (*ssh_protocol)(unsigned char *in, int inlen, int ispkt);
308 static void ssh1_protocol(unsigned char *in, int inlen, int ispkt);
309 static void ssh2_protocol(unsigned char *in, int inlen, int ispkt);
310 static void ssh_size(void);
312 static int (*s_rdpkt)(unsigned char **data, int *datalen);
315 * Collect incoming data in the incoming packet buffer.
316 * Decipher and verify the packet when it is completely read.
317 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
318 * Update the *data and *datalen variables.
319 * Return the additional nr of bytes needed, or 0 when
320 * a complete packet is available.
322 static int ssh1_rdpkt(unsigned char **data, int *datalen)
324 static long len, pad, biglen, to_read;
325 static unsigned long realcrc, gotcrc;
326 static unsigned char *p;
336 for (i = len = 0; i < 4; i++) {
337 while ((*datalen) == 0)
339 len = (len << 8) + **data;
340 (*data)++, (*datalen)--;
344 if (len == 0x52656d6f) { /* "Remo"te server has closed ... */
345 len = 0x300; /* big enough to carry to end */
351 pktin.length = len - 5;
353 if (pktin.maxlen < biglen) {
354 pktin.maxlen = biglen;
355 pktin.data = (pktin.data == NULL ? malloc(biglen+APIEXTRA) :
356 realloc(pktin.data, biglen+APIEXTRA));
358 fatalbox("Out of memory");
363 while (to_read > 0) {
366 while ((*datalen) == 0)
368 if (chunk > (*datalen))
370 memcpy(p, *data, chunk);
378 cipher->decrypt(pktin.data, biglen);
380 pktin.type = pktin.data[pad];
381 pktin.body = pktin.data + pad + 1;
383 realcrc = crc32(pktin.data, biglen-4);
384 gotcrc = GET_32BIT(pktin.data+biglen-4);
385 if (gotcrc != realcrc) {
386 bombout(("Incorrect CRC received on packet"));
390 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
391 pktin.type == SSH1_SMSG_STDERR_DATA ||
392 pktin.type == SSH1_MSG_DEBUG ||
393 pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE ||
394 pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
395 long strlen = GET_32BIT(pktin.body);
396 if (strlen + 4 != pktin.length) {
397 bombout(("Received data packet with bogus string length"));
402 if (pktin.type == SSH1_MSG_DEBUG) {
403 /* log debug message */
405 int strlen = GET_32BIT(pktin.body);
406 strcpy(buf, "Remote: ");
407 if (strlen > 70) strlen = 70;
408 memcpy(buf+8, pktin.body+4, strlen);
409 buf[8+strlen] = '\0';
412 } else if (pktin.type == SSH1_MSG_IGNORE) {
420 static int ssh2_rdpkt(unsigned char **data, int *datalen)
422 static long len, pad, payload, packetlen, maclen;
424 static int cipherblk;
425 static unsigned long incoming_sequence = 0;
435 cipherblk = cipher->blksize;
441 if (pktin.maxlen < cipherblk) {
442 pktin.maxlen = cipherblk;
443 pktin.data = (pktin.data == NULL ? malloc(cipherblk+APIEXTRA) :
444 realloc(pktin.data, cipherblk+APIEXTRA));
446 fatalbox("Out of memory");
450 * Acquire and decrypt the first block of the packet. This will
451 * contain the length and padding details.
453 for (i = len = 0; i < cipherblk; i++) {
454 while ((*datalen) == 0)
455 crReturn(cipherblk-i);
456 pktin.data[i] = *(*data)++;
460 if (!memcmp(pktin.data, "Remo", 4)) {/* "Remo"te server has closed ... */
465 sccipher->decrypt(pktin.data, cipherblk);
468 * Now get the length and padding figures.
470 len = GET_32BIT(pktin.data);
474 * This enables us to deduce the payload length.
476 payload = len - pad - 1;
478 pktin.length = payload + 5;
481 * So now we can work out the total packet length.
484 maclen = scmac ? scmac->len : 0;
487 * Adjust memory allocation if packet is too big.
489 if (pktin.maxlen < packetlen+maclen) {
490 pktin.maxlen = packetlen+maclen;
491 pktin.data = (pktin.data == NULL ? malloc(pktin.maxlen+APIEXTRA) :
492 realloc(pktin.data, pktin.maxlen+APIEXTRA));
494 fatalbox("Out of memory");
498 * Read and decrypt the remainder of the packet.
500 for (i = cipherblk; i < packetlen + maclen; i++) {
501 while ((*datalen) == 0)
502 crReturn(packetlen + maclen - i);
503 pktin.data[i] = *(*data)++;
506 /* Decrypt everything _except_ the MAC. */
508 sccipher->decrypt(pktin.data + cipherblk, packetlen - cipherblk);
511 debug(("Got packet len=%d pad=%d\r\n", len, pad));
512 for (i = 0; i < packetlen; i++)
513 debug((" %02x", (unsigned char)pktin.data[i]));
520 if (scmac && !scmac->verify(pktin.data, len+4, incoming_sequence)) {
521 bombout(("Incorrect MAC received on packet"));
524 incoming_sequence++; /* whether or not we MACed */
527 pktin.type = pktin.data[5];
529 if (pktin.type == SSH2_MSG_IGNORE || pktin.type == SSH2_MSG_DEBUG)
530 goto next_packet; /* FIXME: print DEBUG message */
535 static void ssh_gotdata(unsigned char *data, int datalen)
537 while (datalen > 0) {
538 if ( s_rdpkt(&data, &datalen) == 0 ) {
539 ssh_protocol(NULL, 0, 1);
540 if (ssh_state == SSH_STATE_CLOSED) {
548 static void s_wrpkt_start(int type, int len) {
551 len += 5; /* type and CRC */
555 pktout.length = len-5;
556 if (pktout.maxlen < biglen) {
557 pktout.maxlen = biglen;
559 /* Allocate enough buffer space for extra block
560 * for MS CryptEncrypt() */
561 pktout.data = (pktout.data == NULL ? malloc(biglen+12) :
562 realloc(pktout.data, biglen+12));
564 pktout.data = (pktout.data == NULL ? malloc(biglen+4) :
565 realloc(pktout.data, biglen+4));
568 fatalbox("Out of memory");
572 pktout.body = pktout.data+4+pad+1;
575 static void s_wrpkt(void) {
576 int pad, len, biglen, i;
579 len = pktout.length + 5; /* type and CRC */
583 pktout.body[-1] = pktout.type;
584 for (i=0; i<pad; i++)
585 pktout.data[i+4] = random_byte();
586 crc = crc32(pktout.data+4, biglen-4);
587 PUT_32BIT(pktout.data+biglen, crc);
588 PUT_32BIT(pktout.data, len);
591 cipher->encrypt(pktout.data+4, biglen);
593 s_write(pktout.data, biglen+4);
597 * Construct a packet with the specified contents and
598 * send it to the server.
600 static void send_packet(int pkttype, ...)
603 unsigned char *p, *argp, argchar;
604 unsigned long argint;
605 int pktlen, argtype, arglen;
609 va_start(args, pkttype);
610 while ((argtype = va_arg(args, int)) != PKT_END) {
613 (void) va_arg(args, int);
617 (void) va_arg(args, char);
621 (void) va_arg(args, unsigned char *);
622 arglen = va_arg(args, int);
626 argp = va_arg(args, unsigned char *);
627 arglen = strlen(argp);
628 pktlen += 4 + arglen;
631 bn = va_arg(args, Bignum);
632 pktlen += ssh1_bignum_length(bn);
640 s_wrpkt_start(pkttype, pktlen);
643 va_start(args, pkttype);
644 while ((argtype = va_arg(args, int)) != PKT_END) {
647 argint = va_arg(args, int);
648 PUT_32BIT(p, argint);
652 argchar = va_arg(args, unsigned char);
657 argp = va_arg(args, unsigned char *);
658 arglen = va_arg(args, int);
659 memcpy(p, argp, arglen);
663 argp = va_arg(args, unsigned char *);
664 arglen = strlen(argp);
665 PUT_32BIT(p, arglen);
666 memcpy(p + 4, argp, arglen);
670 bn = va_arg(args, Bignum);
671 p += ssh1_write_bignum(p, bn);
682 * Connect to specified host and port.
683 * Returns an error message, or NULL on success.
684 * Also places the canonical host name into `realhost'.
686 static char *connect_to_host(char *host, int port, char **realhost)
696 savedhost = malloc(1+strlen(host));
698 fatalbox("Out of memory");
699 strcpy(savedhost, host);
702 port = 22; /* default ssh port */
714 if ( (a = inet_addr(host)) == (unsigned long) INADDR_NONE) {
715 if ( (h = gethostbyname(host)) == NULL)
716 switch (WSAGetLastError()) {
717 case WSAENETDOWN: return "Network is down";
718 case WSAHOST_NOT_FOUND: case WSANO_DATA:
719 return "Host does not exist";
720 case WSATRY_AGAIN: return "Host not found";
721 default: return "gethostbyname: unknown error";
723 memcpy (&a, h->h_addr, sizeof(a));
724 *realhost = h->h_name;
735 s = socket(AF_INET, SOCK_STREAM, 0);
736 if (s == INVALID_SOCKET)
737 switch (WSAGetLastError()) {
738 case WSAENETDOWN: return "Network is down";
739 case WSAEAFNOSUPPORT: return "TCP/IP support not present";
740 default: return "socket(): unknown error";
744 * Bind to local address.
746 addr.sin_family = AF_INET;
747 addr.sin_addr.s_addr = htonl(INADDR_ANY);
748 addr.sin_port = htons(0);
749 if (bind (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
750 switch (WSAGetLastError()) {
751 case WSAENETDOWN: return "Network is down";
752 default: return "bind(): unknown error";
756 * Connect to remote address.
758 addr.sin_addr.s_addr = htonl(a);
759 addr.sin_port = htons((short)port);
760 if (connect (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
761 switch (WSAGetLastError()) {
762 case WSAENETDOWN: return "Network is down";
763 case WSAECONNREFUSED: return "Connection refused";
764 case WSAENETUNREACH: return "Network is unreachable";
765 case WSAEHOSTUNREACH: return "No route to host";
766 default: return "connect(): unknown error";
770 send(s, "connect ", 8, 0);
771 send(s, FWhost, strlen(FWhost), 0);
774 sprintf(buf, " %d\n", FWport);
775 send (s, buf, strlen(buf), 0);
782 static int ssh_versioncmp(char *a, char *b) {
784 unsigned long av, bv;
786 av = strtoul(a, &ae, 10);
787 bv = strtoul(b, &be, 10);
788 if (av != bv) return (av < bv ? -1 : +1);
789 if (*ae == '.') ae++;
790 if (*be == '.') be++;
791 av = strtoul(ae, &ae, 10);
792 bv = strtoul(be, &be, 10);
793 if (av != bv) return (av < bv ? -1 : +1);
799 * Utility routine for putting an SSH-protocol `string' into a SHA
803 void sha_string(SHA_State *s, void *str, int len) {
804 unsigned char lenblk[4];
805 PUT_32BIT(lenblk, len);
806 SHA_Bytes(s, lenblk, 4);
807 SHA_Bytes(s, str, len);
811 * SSH2 packet construction functions.
813 void ssh2_pkt_adddata(void *data, int len) {
814 pktout.length += len;
815 if (pktout.maxlen < pktout.length) {
816 pktout.maxlen = pktout.length + 256;
817 pktout.data = (pktout.data == NULL ? malloc(pktout.maxlen+APIEXTRA) :
818 realloc(pktout.data, pktout.maxlen+APIEXTRA));
820 fatalbox("Out of memory");
822 memcpy(pktout.data+pktout.length-len, data, len);
824 void ssh2_pkt_addbyte(unsigned char byte) {
825 ssh2_pkt_adddata(&byte, 1);
827 void ssh2_pkt_init(int pkt_type) {
829 ssh2_pkt_addbyte((unsigned char)pkt_type);
831 void ssh2_pkt_addbool(unsigned char value) {
832 ssh2_pkt_adddata(&value, 1);
834 void ssh2_pkt_adduint32(unsigned long value) {
837 ssh2_pkt_adddata(x, 4);
839 void ssh2_pkt_addstring_start(void) {
840 ssh2_pkt_adduint32(0);
841 pktout.savedpos = pktout.length;
843 void ssh2_pkt_addstring_str(char *data) {
844 ssh2_pkt_adddata(data, strlen(data));
845 PUT_32BIT(pktout.data + pktout.savedpos - 4,
846 pktout.length - pktout.savedpos);
848 void ssh2_pkt_addstring_data(char *data, int len) {
849 ssh2_pkt_adddata(data, len);
850 PUT_32BIT(pktout.data + pktout.savedpos - 4,
851 pktout.length - pktout.savedpos);
853 void ssh2_pkt_addstring(char *data) {
854 ssh2_pkt_addstring_start();
855 ssh2_pkt_addstring_str(data);
857 char *ssh2_mpint_fmt(Bignum b, int *len) {
860 p = malloc(n * 2 + 1);
862 fatalbox("out of memory");
864 for (i = 0; i < n; i++) {
865 p[i*2+1] = (b[n-i] >> 8) & 0xFF;
866 p[i*2+2] = (b[n-i] ) & 0xFF;
869 while (p[i] == 0 && (p[i+1] & 0x80) == 0)
871 memmove(p, p+i, n*2+1-i);
875 void ssh2_pkt_addmp(Bignum b) {
878 p = ssh2_mpint_fmt(b, &len);
879 ssh2_pkt_addstring_start();
880 ssh2_pkt_addstring_data(p, len);
883 void ssh2_pkt_send(void) {
884 int cipherblk, maclen, padding, i;
885 static unsigned long outgoing_sequence = 0;
888 * Add padding. At least four bytes, and must also bring total
889 * length (minus MAC) up to a multiple of the block size.
891 cipherblk = cipher ? cipher->blksize : 8; /* block size */
892 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
894 padding += (cipherblk - (pktout.length + padding) % cipherblk) % cipherblk;
895 pktout.data[4] = padding;
896 for (i = 0; i < padding; i++)
897 pktout.data[pktout.length + i] = random_byte();
898 PUT_32BIT(pktout.data, pktout.length + padding - 4);
900 csmac->generate(pktout.data, pktout.length + padding,
902 outgoing_sequence++; /* whether or not we MACed */
905 debug(("Sending packet len=%d\r\n", pktout.length+padding));
906 for (i = 0; i < pktout.length+padding; i++)
907 debug((" %02x", (unsigned char)pktout.data[i]));
912 cscipher->encrypt(pktout.data, pktout.length + padding);
913 maclen = csmac ? csmac->len : 0;
915 s_write(pktout.data, pktout.length + padding + maclen);
919 void bndebug(char *string, Bignum b) {
922 p = ssh2_mpint_fmt(b, &len);
923 debug(("%s", string));
924 for (i = 0; i < len; i++)
925 debug((" %02x", p[i]));
931 void sha_mpint(SHA_State *s, Bignum b) {
934 p = ssh2_mpint_fmt(b, &len);
935 sha_string(s, p, len);
940 * SSH2 packet decode functions.
942 unsigned long ssh2_pkt_getuint32(void) {
944 if (pktin.length - pktin.savedpos < 4)
945 return 0; /* arrgh, no way to decline (FIXME?) */
946 value = GET_32BIT(pktin.data+pktin.savedpos);
950 void ssh2_pkt_getstring(char **p, int *length) {
952 if (pktin.length - pktin.savedpos < 4)
954 *length = GET_32BIT(pktin.data+pktin.savedpos);
956 if (pktin.length - pktin.savedpos < *length)
958 *p = pktin.data+pktin.savedpos;
959 pktin.savedpos += *length;
961 Bignum ssh2_pkt_getmp(void) {
966 ssh2_pkt_getstring(&p, &length);
970 bombout(("internal error: Can't handle negative mpints"));
973 b = newbn((length+1)/2);
974 for (i = 0; i < length; i++) {
977 b[j/2+1] |= ((unsigned char)p[i]) << 8;
979 b[j/2+1] |= ((unsigned char)p[i]);
984 static int do_ssh_init(void) {
988 char vlog[sizeof(vstring)+20];
993 while (s_read(&c, 1) == 1) {
994 if (c == 'S' && i < 2) i++;
995 else if (c == 'S' && i == 2) i = 2;
996 else if (c == 'H' && i == 2) break;
1000 if (s_read(&c,1) != 1 || c != 'S') return 0;
1001 if (s_read(&c,1) != 1 || c != 'S') return 0;
1002 if (s_read(&c,1) != 1 || c != 'H') return 0;
1004 strcpy(vstring, "SSH-");
1006 if (s_read(&c,1) != 1 || c != '-') return 0;
1009 if (s_read(&c,1) != 1)
1011 if (vsp < vstring+sizeof(vstring)-1)
1017 } else if (i < sizeof(version)-1)
1025 sprintf(vlog, "Server version: %s", vstring);
1026 vlog[strcspn(vlog, "\r\n")] = '\0';
1030 * Server version "1.99" means we can choose whether we use v1
1031 * or v2 protocol. Choice is based on cfg.sshprot.
1033 if (ssh_versioncmp(version, cfg.sshprot == 1 ? "2.0" : "1.99") >= 0) {
1035 * This is a v2 server. Begin v2 protocol.
1037 char *verstring = "SSH-2.0-PuTTY";
1040 * Hash our version string and their version string.
1042 sha_string(&exhash, verstring, strlen(verstring));
1043 sha_string(&exhash, vstring, strcspn(vstring, "\r\n"));
1044 sprintf(vstring, "%s\n", verstring);
1045 sprintf(vlog, "We claim version: %s", verstring);
1047 logevent("Using SSH protocol version 2");
1048 s_write(vstring, strlen(vstring));
1049 ssh_protocol = ssh2_protocol;
1051 s_rdpkt = ssh2_rdpkt;
1054 * This is a v1 server. Begin v1 protocol.
1056 sprintf(vstring, "SSH-%s-PuTTY\n",
1057 (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5"));
1058 sprintf(vlog, "We claim version: %s", vstring);
1059 vlog[strcspn(vlog, "\r\n")] = '\0';
1061 logevent("Using SSH protocol version 1");
1062 s_write(vstring, strlen(vstring));
1063 ssh_protocol = ssh1_protocol;
1065 s_rdpkt = ssh1_rdpkt;
1072 * Handle the key exchange and user authentication phases.
1074 static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
1077 unsigned char *rsabuf, *keystr1, *keystr2;
1078 unsigned char cookie[8];
1079 struct RSAKey servkey, hostkey;
1080 struct MD5Context md5c;
1081 static unsigned long supported_ciphers_mask, supported_auths_mask;
1082 static int tried_publickey;
1083 static unsigned char session_id[16];
1088 if (!ispkt) crWaitUntil(ispkt);
1090 if (pktin.type != SSH1_SMSG_PUBLIC_KEY) {
1091 bombout(("Public key packet not received"));
1095 logevent("Received public keys");
1097 memcpy(cookie, pktin.body, 8);
1099 i = makekey(pktin.body+8, &servkey, &keystr1, 0);
1100 j = makekey(pktin.body+8+i, &hostkey, &keystr2, 0);
1103 * Hash the host key and print the hash in the log box. Just as
1104 * a last resort in case the registry's host key checking is
1105 * compromised, we'll allow the user some ability to verify
1109 MD5Update(&md5c, keystr2, hostkey.bytes);
1110 MD5Final(session_id, &md5c);
1114 logevent("Host key MD5 is:");
1115 strcpy(logmsg, " ");
1116 for (i = 0; i < 16; i++)
1117 sprintf(logmsg+strlen(logmsg), "%02x", session_id[i]);
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 *keystr = malloc(len);
1149 fatalbox("Out of memory");
1150 rsastr_fmt(keystr, &hostkey);
1151 verify_ssh_host_key(savedhost, keystr);
1155 for (i=0; i<32; i++) {
1156 rsabuf[i] = session_key[i];
1158 rsabuf[i] ^= session_id[i];
1161 if (hostkey.bytes > servkey.bytes) {
1162 rsaencrypt(rsabuf, 32, &servkey);
1163 rsaencrypt(rsabuf, servkey.bytes, &hostkey);
1165 rsaencrypt(rsabuf, 32, &hostkey);
1166 rsaencrypt(rsabuf, hostkey.bytes, &servkey);
1169 logevent("Encrypted session key");
1171 cipher_type = cfg.cipher == CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH :
1172 cfg.cipher == CIPHER_DES ? SSH_CIPHER_DES :
1174 if ((supported_ciphers_mask & (1 << cipher_type)) == 0) {
1175 c_write("Selected cipher not supported, falling back to 3DES\r\n", 53);
1176 cipher_type = SSH_CIPHER_3DES;
1178 switch (cipher_type) {
1179 case SSH_CIPHER_3DES: logevent("Using 3DES encryption"); break;
1180 case SSH_CIPHER_DES: logevent("Using single-DES encryption"); break;
1181 case SSH_CIPHER_BLOWFISH: logevent("Using Blowfish encryption"); break;
1184 send_packet(SSH1_CMSG_SESSION_KEY,
1185 PKT_CHAR, cipher_type,
1186 PKT_DATA, cookie, 8,
1187 PKT_CHAR, (len*8) >> 8, PKT_CHAR, (len*8) & 0xFF,
1188 PKT_DATA, rsabuf, len,
1192 logevent("Trying to enable encryption...");
1196 cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
1197 cipher_type == SSH_CIPHER_DES ? &ssh_des :
1199 cipher->sesskey(session_key);
1203 if (pktin.type != SSH1_SMSG_SUCCESS) {
1204 bombout(("Encryption not successfully enabled"));
1208 logevent("Successfully started encryption");
1212 static char username[100];
1215 if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
1216 c_write("login as: ", 10);
1219 crWaitUntil(!ispkt);
1220 while (inlen--) switch (c = *in++) {
1227 c_write("\b \b", 3);
1233 c_write("\b \b", 3);
1242 if (((c >= ' ' && c <= '~') ||
1243 ((unsigned char)c >= 160)) && pos < 40) {
1244 username[pos++] = c;
1251 username[strcspn(username, "\n\r")] = '\0';
1254 strncpy(username, cfg.username, 99);
1255 username[99] = '\0';
1256 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
1257 sprintf(stuff, "Sent username \"%s\".\r\n", username);
1258 c_write(stuff, strlen(stuff));
1262 send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END);
1264 char userlog[20+sizeof(username)];
1265 sprintf(userlog, "Sent username \"%s\"", username);
1272 tried_publickey = 0;
1274 while (pktin.type == SSH1_SMSG_FAILURE) {
1275 static char password[100];
1278 static int pwpkt_type;
1280 * Show password prompt, having first obtained it via a TIS
1281 * or CryptoCard exchange if we're doing TIS or CryptoCard
1284 pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
1285 if (agent_exists()) {
1287 * Attempt RSA authentication using Pageant.
1289 static unsigned char request[5], *response, *p;
1290 static int responselen;
1291 static int i, nkeys;
1292 static int authed = FALSE;
1295 logevent("Pageant is running. Requesting keys.");
1297 /* Request the keys held by the agent. */
1298 PUT_32BIT(request, 1);
1299 request[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES;
1300 agent_query(request, 5, &r, &responselen);
1301 response = (unsigned char *)r;
1304 nkeys = GET_32BIT(p); p += 4;
1305 { char buf[64]; sprintf(buf, "Pageant has %d keys", nkeys);
1307 for (i = 0; i < nkeys; i++) {
1308 static struct RSAKey key;
1309 static Bignum challenge;
1310 static char *commentp;
1311 static int commentlen;
1313 { char buf[64]; sprintf(buf, "Trying Pageant key #%d", i);
1316 p += ssh1_read_bignum(p, &key.exponent);
1317 p += ssh1_read_bignum(p, &key.modulus);
1318 commentlen = GET_32BIT(p); p += 4;
1319 commentp = p; p += commentlen;
1320 send_packet(SSH1_CMSG_AUTH_RSA,
1321 PKT_BIGNUM, key.modulus, PKT_END);
1323 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
1324 logevent("Key refused");
1327 logevent("Received RSA challenge");
1328 ssh1_read_bignum(pktin.body, &challenge);
1330 char *agentreq, *q, *ret;
1332 len = 1 + 4; /* message type, bit count */
1333 len += ssh1_bignum_length(key.exponent);
1334 len += ssh1_bignum_length(key.modulus);
1335 len += ssh1_bignum_length(challenge);
1336 len += 16; /* session id */
1337 len += 4; /* response format */
1338 agentreq = malloc(4 + len);
1339 PUT_32BIT(agentreq, len);
1341 *q++ = SSH_AGENTC_RSA_CHALLENGE;
1342 PUT_32BIT(q, ssh1_bignum_bitcount(key.modulus));
1344 q += ssh1_write_bignum(q, key.exponent);
1345 q += ssh1_write_bignum(q, key.modulus);
1346 q += ssh1_write_bignum(q, challenge);
1347 memcpy(q, session_id, 16); q += 16;
1348 PUT_32BIT(q, 1); /* response format */
1349 agent_query(agentreq, len+4, &ret, &retlen);
1352 if (ret[4] == SSH_AGENT_RSA_RESPONSE) {
1353 logevent("Sending Pageant's response");
1354 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
1355 PKT_DATA, ret+5, 16, PKT_END);
1358 if (pktin.type == SSH1_SMSG_SUCCESS) {
1359 logevent("Pageant's response accepted");
1360 c_write("Authenticated using RSA key \"",
1362 c_write(commentp, commentlen);
1363 c_write("\" from agent\r\n", 14);
1366 logevent("Pageant's response not accepted");
1368 logevent("Pageant failed to answer challenge");
1372 logevent("No reply received from Pageant");
1375 freebn(key.exponent);
1376 freebn(key.modulus);
1385 if (*cfg.keyfile && !tried_publickey)
1386 pwpkt_type = SSH1_CMSG_AUTH_RSA;
1388 if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD &&
1389 !(flags & FLAG_INTERACTIVE)) {
1391 sprintf(prompt, "%s@%s's password: ", cfg.username, savedhost);
1392 if (!ssh_get_password(prompt, password, sizeof(password))) {
1394 * get_password failed to get a password (for
1395 * example because one was supplied on the command
1396 * line which has already failed to work).
1399 logevent("No more passwords to try");
1400 ssh_state = SSH_STATE_CLOSED;
1405 if (pktin.type == SSH1_SMSG_FAILURE &&
1407 (supported_auths_mask & (1<<SSH1_AUTH_TIS))) {
1408 pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
1409 logevent("Requested TIS authentication");
1410 send_packet(SSH1_CMSG_AUTH_TIS, PKT_END);
1412 if (pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
1413 logevent("TIS authentication declined");
1414 c_write("TIS authentication refused.\r\n", 29);
1416 int challengelen = ((pktin.body[0] << 24) |
1417 (pktin.body[1] << 16) |
1418 (pktin.body[2] << 8) |
1420 logevent("Received TIS challenge");
1421 c_write(pktin.body+4, challengelen);
1424 if (pktin.type == SSH1_SMSG_FAILURE &&
1426 (supported_auths_mask & (1<<SSH1_AUTH_CCARD))) {
1427 pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
1428 logevent("Requested CryptoCard authentication");
1429 send_packet(SSH1_CMSG_AUTH_CCARD, PKT_END);
1431 if (pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
1432 logevent("CryptoCard authentication declined");
1433 c_write("CryptoCard authentication refused.\r\n", 29);
1435 int challengelen = ((pktin.body[0] << 24) |
1436 (pktin.body[1] << 16) |
1437 (pktin.body[2] << 8) |
1439 logevent("Received CryptoCard challenge");
1440 c_write(pktin.body+4, challengelen);
1441 c_write("\r\nResponse : ", 13);
1444 if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD)
1445 c_write("password: ", 10);
1446 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
1447 if (flags & FLAG_VERBOSE)
1448 c_write("Trying public key authentication.\r\n", 35);
1449 if (!rsakey_encrypted(cfg.keyfile)) {
1450 if (flags & FLAG_VERBOSE)
1451 c_write("No passphrase required.\r\n", 25);
1454 c_write("passphrase: ", 12);
1460 crWaitUntil(!ispkt);
1461 while (inlen--) switch (c = *in++) {
1478 if (((c >= ' ' && c <= '~') ||
1479 ((unsigned char)c >= 160)) && pos < sizeof(password))
1480 password[pos++] = c;
1489 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
1491 * Try public key authentication with the specified
1494 static struct RSAKey pubkey;
1495 static Bignum challenge, response;
1497 static unsigned char buffer[32];
1499 tried_publickey = 1;
1500 i = loadrsakey(cfg.keyfile, &pubkey, password);
1502 c_write("Couldn't load public key from ", 30);
1503 c_write(cfg.keyfile, strlen(cfg.keyfile));
1504 c_write(".\r\n", 3);
1505 continue; /* go and try password */
1508 c_write("Wrong passphrase.\r\n", 19);
1509 tried_publickey = 0;
1510 continue; /* try again */
1514 * Send a public key attempt.
1516 send_packet(SSH1_CMSG_AUTH_RSA,
1517 PKT_BIGNUM, pubkey.modulus, PKT_END);
1520 if (pktin.type == SSH1_SMSG_FAILURE) {
1521 if (flags & FLAG_VERBOSE)
1522 c_write("Server refused our public key.\r\n", 32);
1523 continue; /* go and try password */
1525 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
1526 bombout(("Bizarre response to offer of public key"));
1529 ssh1_read_bignum(pktin.body, &challenge);
1530 response = rsadecrypt(challenge, &pubkey);
1531 freebn(pubkey.private_exponent); /* burn the evidence */
1533 for (i = 0; i < 32; i += 2) {
1534 buffer[i] = response[16-i/2] >> 8;
1535 buffer[i+1] = response[16-i/2] & 0xFF;
1539 MD5Update(&md5c, buffer, 32);
1540 MD5Update(&md5c, session_id, 16);
1541 MD5Final(buffer, &md5c);
1543 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
1544 PKT_DATA, buffer, 16, PKT_END);
1547 if (pktin.type == SSH1_SMSG_FAILURE) {
1548 if (flags & FLAG_VERBOSE)
1549 c_write("Failed to authenticate with our public key.\r\n",
1551 continue; /* go and try password */
1552 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
1553 bombout(("Bizarre response to RSA authentication response"));
1557 break; /* we're through! */
1559 send_packet(pwpkt_type, PKT_STR, password, PKT_END);
1561 logevent("Sent password");
1562 memset(password, 0, strlen(password));
1564 if (pktin.type == SSH1_SMSG_FAILURE) {
1565 if (flags & FLAG_VERBOSE)
1566 c_write("Access denied\r\n", 15);
1567 logevent("Authentication refused");
1568 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
1569 logevent("Received disconnect request");
1570 ssh_state = SSH_STATE_CLOSED;
1572 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
1573 bombout(("Strange packet received, type %d", pktin.type));
1578 logevent("Authentication successful");
1583 static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) {
1588 while (!do_ssh1_login(in, inlen, ispkt)) {
1591 if (ssh_state == SSH_STATE_CLOSED)
1594 if (cfg.agentfwd && agent_exists()) {
1595 logevent("Requesting agent forwarding");
1596 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
1597 do { crReturnV; } while (!ispkt);
1598 if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
1599 bombout(("Protocol confusion"));
1601 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1602 logevent("Agent forwarding refused");
1604 logevent("Agent forwarding enabled");
1608 send_packet(SSH1_CMSG_REQUEST_PTY,
1609 PKT_STR, cfg.termtype,
1610 PKT_INT, rows, PKT_INT, cols,
1611 PKT_INT, 0, PKT_INT, 0,
1614 ssh_state = SSH_STATE_INTERMED;
1615 do { crReturnV; } while (!ispkt);
1616 if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
1617 bombout(("Protocol confusion"));
1619 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1620 c_write("Server refused to allocate pty\r\n", 32);
1622 logevent("Allocated pty");
1625 if (*cfg.remote_cmd)
1626 send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cfg.remote_cmd, PKT_END);
1628 send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END);
1629 logevent("Started session");
1631 ssh_state = SSH_STATE_SESSION;
1636 ssh_channels = newtree234(ssh_channelcmp);
1641 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
1642 pktin.type == SSH1_SMSG_STDERR_DATA) {
1643 long len = GET_32BIT(pktin.body);
1644 c_write(pktin.body+4, len);
1645 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
1646 ssh_state = SSH_STATE_CLOSED;
1647 logevent("Received disconnect request");
1648 } else if (pktin.type == SSH1_SMSG_AGENT_OPEN) {
1649 /* Remote side is trying to open a channel to talk to our
1650 * agent. Give them back a local channel number. */
1652 struct ssh_channel *c;
1654 for (c = first234(ssh_channels, &e); c; c = next234(&e)) {
1656 break; /* found a free number */
1659 c = malloc(sizeof(struct ssh_channel));
1660 c->remoteid = GET_32BIT(pktin.body);
1663 c->type = SSH1_SMSG_AGENT_OPEN; /* identify channel type */
1664 add234(ssh_channels, c);
1665 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
1666 PKT_INT, c->remoteid, PKT_INT, c->localid,
1668 } else if (pktin.type == SSH1_MSG_CHANNEL_CLOSE ||
1669 pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
1670 /* Remote side closes a channel. */
1671 unsigned i = GET_32BIT(pktin.body);
1672 struct ssh_channel *c;
1673 c = find234(ssh_channels, &i, ssh_channelfind);
1676 closetype = (pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
1677 send_packet(pktin.type, PKT_INT, c->remoteid, PKT_END);
1678 c->closes |= closetype;
1679 if (c->closes == 3) {
1680 del234(ssh_channels, c);
1684 } else if (pktin.type == SSH1_MSG_CHANNEL_DATA) {
1685 /* Data sent down one of our channels. */
1686 int i = GET_32BIT(pktin.body);
1687 int len = GET_32BIT(pktin.body+4);
1688 unsigned char *p = pktin.body+8;
1689 struct ssh_channel *c;
1690 c = find234(ssh_channels, &i, ssh_channelfind);
1693 case SSH1_SMSG_AGENT_OPEN:
1694 /* Data for an agent message. Buffer it. */
1696 if (c->u.a.lensofar < 4) {
1697 int l = min(4 - c->u.a.lensofar, len);
1698 memcpy(c->u.a.msglen + c->u.a.lensofar, p, l);
1699 p += l; len -= l; c->u.a.lensofar += l;
1701 if (c->u.a.lensofar == 4) {
1702 c->u.a.totallen = 4 + GET_32BIT(c->u.a.msglen);
1703 c->u.a.message = malloc(c->u.a.totallen);
1704 memcpy(c->u.a.message, c->u.a.msglen, 4);
1706 if (c->u.a.lensofar >= 4 && len > 0) {
1707 int l = min(c->u.a.totallen - c->u.a.lensofar, len);
1708 memcpy(c->u.a.message + c->u.a.lensofar, p, l);
1709 p += l; len -= l; c->u.a.lensofar += l;
1711 if (c->u.a.lensofar == c->u.a.totallen) {
1712 void *reply, *sentreply;
1714 agent_query(c->u.a.message, c->u.a.totallen,
1719 /* Fake SSH_AGENT_FAILURE. */
1720 sentreply = "\0\0\0\1\5";
1723 send_packet(SSH1_MSG_CHANNEL_DATA,
1724 PKT_INT, c->remoteid,
1726 PKT_DATA, sentreply, replylen,
1730 free(c->u.a.message);
1731 c->u.a.lensofar = 0;
1737 } else if (pktin.type == SSH1_SMSG_SUCCESS) {
1738 /* may be from EXEC_SHELL on some servers */
1739 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1740 /* may be from EXEC_SHELL on some servers
1741 * if no pty is available or in other odd cases. Ignore */
1742 } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) {
1743 send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
1745 bombout(("Strange packet received: type %d", pktin.type));
1749 send_packet(SSH1_CMSG_STDIN_DATA,
1750 PKT_INT, inlen, PKT_DATA, in, inlen, PKT_END);
1758 * Utility routine for decoding comma-separated strings in KEXINIT.
1760 int in_commasep_string(char *needle, char *haystack, int haylen) {
1761 int needlen = strlen(needle);
1764 * Is it at the start of the string?
1766 if (haylen >= needlen && /* haystack is long enough */
1767 !memcmp(needle, haystack, needlen) && /* initial match */
1768 (haylen == needlen || haystack[needlen] == ',')
1769 /* either , or EOS follows */
1773 * If not, search for the next comma and resume after that.
1774 * If no comma found, terminate.
1776 while (haylen > 0 && *haystack != ',')
1777 haylen--, haystack++;
1780 haylen--, haystack++; /* skip over comma itself */
1785 * SSH2 key creation method.
1787 void ssh2_mkkey(Bignum K, char *H, char chr, char *keyspace) {
1789 /* First 20 bytes. */
1792 SHA_Bytes(&s, H, 20);
1793 SHA_Bytes(&s, &chr, 1);
1794 SHA_Bytes(&s, H, 20);
1795 SHA_Final(&s, keyspace);
1796 /* Next 20 bytes. */
1799 SHA_Bytes(&s, H, 20);
1800 SHA_Bytes(&s, keyspace, 20);
1801 SHA_Final(&s, keyspace+20);
1805 * Handle the SSH2 transport layer.
1807 static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt)
1811 static Bignum e, f, K;
1812 static struct ssh_cipher *cscipher_tobe = NULL;
1813 static struct ssh_cipher *sccipher_tobe = NULL;
1814 static struct ssh_mac *csmac_tobe = NULL;
1815 static struct ssh_mac *scmac_tobe = NULL;
1816 static struct ssh_compress *cscomp_tobe = NULL;
1817 static struct ssh_compress *sccomp_tobe = NULL;
1818 static char *hostkeydata, *sigdata, *keystr;
1819 static int hostkeylen, siglen;
1820 static unsigned char exchange_hash[20];
1821 static unsigned char keyspace[40];
1827 * Set up the preferred cipher.
1829 if (cfg.cipher == CIPHER_BLOWFISH) {
1830 ciphers[0] = &ssh_blowfish_ssh2;
1831 } else if (cfg.cipher == CIPHER_DES) {
1832 logevent("Single DES not supported in SSH2; using 3DES");
1833 ciphers[0] = &ssh_3des_ssh2;
1834 } else if (cfg.cipher == CIPHER_3DES) {
1835 ciphers[0] = &ssh_3des_ssh2;
1837 /* Shouldn't happen, but we do want to initialise to _something_. */
1838 ciphers[0] = &ssh_3des_ssh2;
1843 * Construct and send our key exchange packet.
1845 ssh2_pkt_init(SSH2_MSG_KEXINIT);
1846 for (i = 0; i < 16; i++)
1847 ssh2_pkt_addbyte((unsigned char)random_byte());
1848 /* List key exchange algorithms. */
1849 ssh2_pkt_addstring_start();
1850 for (i = 0; i < lenof(kex_algs); i++) {
1851 ssh2_pkt_addstring_str(kex_algs[i]->name);
1852 if (i < lenof(kex_algs)-1)
1853 ssh2_pkt_addstring_str(",");
1855 /* List server host key algorithms. */
1856 ssh2_pkt_addstring_start();
1857 for (i = 0; i < lenof(hostkey_algs); i++) {
1858 ssh2_pkt_addstring_str(hostkey_algs[i]->name);
1859 if (i < lenof(hostkey_algs)-1)
1860 ssh2_pkt_addstring_str(",");
1862 /* List client->server encryption algorithms. */
1863 ssh2_pkt_addstring_start();
1864 for (i = 0; i < lenof(ciphers); i++) {
1865 ssh2_pkt_addstring_str(ciphers[i]->name);
1866 if (i < lenof(ciphers)-1)
1867 ssh2_pkt_addstring_str(",");
1869 /* List server->client encryption algorithms. */
1870 ssh2_pkt_addstring_start();
1871 for (i = 0; i < lenof(ciphers); i++) {
1872 ssh2_pkt_addstring_str(ciphers[i]->name);
1873 if (i < lenof(ciphers)-1)
1874 ssh2_pkt_addstring_str(",");
1876 /* List client->server MAC algorithms. */
1877 ssh2_pkt_addstring_start();
1878 for (i = 0; i < lenof(macs); i++) {
1879 ssh2_pkt_addstring_str(macs[i]->name);
1880 if (i < lenof(macs)-1)
1881 ssh2_pkt_addstring_str(",");
1883 /* List server->client MAC algorithms. */
1884 ssh2_pkt_addstring_start();
1885 for (i = 0; i < lenof(macs); i++) {
1886 ssh2_pkt_addstring_str(macs[i]->name);
1887 if (i < lenof(macs)-1)
1888 ssh2_pkt_addstring_str(",");
1890 /* List client->server compression algorithms. */
1891 ssh2_pkt_addstring_start();
1892 for (i = 0; i < lenof(compressions); i++) {
1893 ssh2_pkt_addstring_str(compressions[i]->name);
1894 if (i < lenof(compressions)-1)
1895 ssh2_pkt_addstring_str(",");
1897 /* List server->client compression algorithms. */
1898 ssh2_pkt_addstring_start();
1899 for (i = 0; i < lenof(compressions); i++) {
1900 ssh2_pkt_addstring_str(compressions[i]->name);
1901 if (i < lenof(compressions)-1)
1902 ssh2_pkt_addstring_str(",");
1904 /* List client->server languages. Empty list. */
1905 ssh2_pkt_addstring_start();
1906 /* List server->client languages. Empty list. */
1907 ssh2_pkt_addstring_start();
1908 /* First KEX packet does _not_ follow, because we're not that brave. */
1909 ssh2_pkt_addbool(FALSE);
1911 ssh2_pkt_adduint32(0);
1912 sha_string(&exhash, pktout.data+5, pktout.length-5);
1915 if (!ispkt) crWaitUntil(ispkt);
1916 sha_string(&exhash, pktin.data+5, pktin.length-5);
1919 * Now examine the other side's KEXINIT to see what we're up
1922 if (pktin.type != SSH2_MSG_KEXINIT) {
1923 bombout(("expected key exchange packet from server"));
1926 kex = NULL; hostkey = NULL; cscipher_tobe = NULL; sccipher_tobe = NULL;
1927 csmac_tobe = NULL; scmac_tobe = NULL; cscomp_tobe = NULL; sccomp_tobe = NULL;
1928 pktin.savedpos += 16; /* skip garbage cookie */
1929 ssh2_pkt_getstring(&str, &len); /* key exchange algorithms */
1930 for (i = 0; i < lenof(kex_algs); i++) {
1931 if (in_commasep_string(kex_algs[i]->name, str, len)) {
1936 ssh2_pkt_getstring(&str, &len); /* host key algorithms */
1937 for (i = 0; i < lenof(hostkey_algs); i++) {
1938 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
1939 hostkey = hostkey_algs[i];
1943 ssh2_pkt_getstring(&str, &len); /* client->server cipher */
1944 for (i = 0; i < lenof(ciphers); i++) {
1945 if (in_commasep_string(ciphers[i]->name, str, len)) {
1946 cscipher_tobe = ciphers[i];
1950 ssh2_pkt_getstring(&str, &len); /* server->client cipher */
1951 for (i = 0; i < lenof(ciphers); i++) {
1952 if (in_commasep_string(ciphers[i]->name, str, len)) {
1953 sccipher_tobe = ciphers[i];
1957 ssh2_pkt_getstring(&str, &len); /* client->server mac */
1958 for (i = 0; i < lenof(macs); i++) {
1959 if (in_commasep_string(macs[i]->name, str, len)) {
1960 csmac_tobe = macs[i];
1964 ssh2_pkt_getstring(&str, &len); /* server->client mac */
1965 for (i = 0; i < lenof(macs); i++) {
1966 if (in_commasep_string(macs[i]->name, str, len)) {
1967 scmac_tobe = macs[i];
1971 ssh2_pkt_getstring(&str, &len); /* client->server compression */
1972 for (i = 0; i < lenof(compressions); i++) {
1973 if (in_commasep_string(compressions[i]->name, str, len)) {
1974 cscomp_tobe = compressions[i];
1978 ssh2_pkt_getstring(&str, &len); /* server->client compression */
1979 for (i = 0; i < lenof(compressions); i++) {
1980 if (in_commasep_string(compressions[i]->name, str, len)) {
1981 sccomp_tobe = compressions[i];
1987 * Currently we only support Diffie-Hellman and DSS, so let's
1988 * bomb out if those aren't selected.
1990 if (kex != &ssh_diffiehellman || hostkey != &ssh_dss) {
1991 bombout(("internal fault: chaos in SSH 2 transport layer"));
1996 * Now we begin the fun. Generate and send e for Diffie-Hellman.
1999 ssh2_pkt_init(SSH2_MSG_KEXDH_INIT);
2004 if (pktin.type != SSH2_MSG_KEXDH_REPLY) {
2005 bombout(("expected key exchange packet from server"));
2008 ssh2_pkt_getstring(&hostkeydata, &hostkeylen);
2009 f = ssh2_pkt_getmp();
2010 ssh2_pkt_getstring(&sigdata, &siglen);
2014 sha_string(&exhash, hostkeydata, hostkeylen);
2015 sha_mpint(&exhash, e);
2016 sha_mpint(&exhash, f);
2017 sha_mpint(&exhash, K);
2018 SHA_Final(&exhash, exchange_hash);
2021 debug(("Exchange hash is:\r\n"));
2022 for (i = 0; i < 20; i++)
2023 debug((" %02x", exchange_hash[i]));
2027 hostkey->setkey(hostkeydata, hostkeylen);
2028 if (!hostkey->verifysig(sigdata, siglen, exchange_hash, 20)) {
2029 bombout(("Server failed host key check"));
2034 * Expect SSH2_MSG_NEWKEYS from server.
2037 if (pktin.type != SSH2_MSG_NEWKEYS) {
2038 bombout(("expected new-keys packet from server"));
2043 * Authenticate remote host: verify host key. (We've already
2044 * checked the signature of the exchange hash.)
2046 keystr = hostkey->fmtkey();
2047 verify_ssh_host_key(savedhost, keystr);
2051 * Send SSH2_MSG_NEWKEYS.
2053 ssh2_pkt_init(SSH2_MSG_NEWKEYS);
2057 * Create and initialise session keys.
2059 cscipher = cscipher_tobe;
2060 sccipher = sccipher_tobe;
2063 cscomp = cscomp_tobe;
2064 sccomp = sccomp_tobe;
2066 * Set IVs after keys.
2068 ssh2_mkkey(K, exchange_hash, 'C', keyspace); cscipher->setcskey(keyspace);
2069 ssh2_mkkey(K, exchange_hash, 'D', keyspace); cscipher->setsckey(keyspace);
2070 ssh2_mkkey(K, exchange_hash, 'A', keyspace); cscipher->setcsiv(keyspace);
2071 ssh2_mkkey(K, exchange_hash, 'B', keyspace); sccipher->setsciv(keyspace);
2072 ssh2_mkkey(K, exchange_hash, 'E', keyspace); csmac->setcskey(keyspace);
2073 ssh2_mkkey(K, exchange_hash, 'F', keyspace); scmac->setsckey(keyspace);
2076 * Now we're encrypting. Begin returning 1 to the protocol main
2077 * function so that other things can run on top of the
2078 * transport. If we ever see a KEXINIT, we must go back to the
2083 } while (!(ispkt && pktin.type == SSH2_MSG_KEXINIT));
2084 goto begin_key_exchange;
2090 * Handle the SSH2 userauth and connection layers.
2092 static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
2094 static unsigned long remote_winsize;
2095 static unsigned long remote_maxpkt;
2100 * Request userauth protocol, and await a response to it.
2102 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
2103 ssh2_pkt_addstring("ssh-userauth");
2105 crWaitUntilV(ispkt);
2106 if (pktin.type != SSH2_MSG_SERVICE_ACCEPT) {
2107 bombout(("Server refused user authentication protocol"));
2112 * FIXME: currently we support only password authentication.
2113 * (This places us technically in violation of the SSH2 spec.
2114 * We must fix this.)
2118 * Get a username and a password.
2120 static char username[100];
2121 static char password[100];
2125 if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
2126 c_write("login as: ", 10);
2129 crWaitUntilV(!ispkt);
2130 while (inlen--) switch (c = *in++) {
2137 c_write("\b \b", 3);
2143 c_write("\b \b", 3);
2152 if (((c >= ' ' && c <= '~') ||
2153 ((unsigned char)c >= 160)) && pos < 40) {
2154 username[pos++] = c;
2161 username[strcspn(username, "\n\r")] = '\0';
2164 strncpy(username, cfg.username, 99);
2165 username[99] = '\0';
2166 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
2167 sprintf(stuff, "Using username \"%s\".\r\n", username);
2168 c_write(stuff, strlen(stuff));
2172 if (!(flags & FLAG_INTERACTIVE)) {
2174 sprintf(prompt, "%s@%s's password: ", cfg.username, savedhost);
2175 if (!ssh_get_password(prompt, password, sizeof(password))) {
2177 * get_password failed to get a password (for
2178 * example because one was supplied on the command
2179 * line which has already failed to work).
2182 logevent("No more passwords to try");
2183 ssh_state = SSH_STATE_CLOSED;
2187 c_write("password: ", 10);
2192 crWaitUntilV(!ispkt);
2193 while (inlen--) switch (c = *in++) {
2210 if (((c >= ' ' && c <= '~') ||
2211 ((unsigned char)c >= 160)) && pos < 40)
2212 password[pos++] = c;
2219 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
2220 ssh2_pkt_addstring(username);
2221 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2222 ssh2_pkt_addstring("password");
2223 ssh2_pkt_addbool(FALSE);
2224 ssh2_pkt_addstring(password);
2227 crWaitUntilV(ispkt);
2228 if (pktin.type != SSH2_MSG_USERAUTH_SUCCESS) {
2229 c_write("Access denied\r\n", 15);
2230 logevent("Authentication refused");
2236 * Now we're authenticated for the connection protocol. The
2237 * connection protocol will automatically have started at this
2238 * point; there's no need to send SERVICE_REQUEST.
2242 * So now create a channel with a session in it.
2244 mainchan = malloc(sizeof(struct ssh_channel));
2245 mainchan->localid = 100; /* as good as any */
2246 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
2247 ssh2_pkt_addstring("session");
2248 ssh2_pkt_adduint32(mainchan->localid);
2249 ssh2_pkt_adduint32(0x7FFFFFFFUL); /* our window size */
2250 ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
2252 crWaitUntilV(ispkt);
2253 if (pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
2254 bombout(("Server refused to open a session"));
2256 /* FIXME: error data comes back in FAILURE packet */
2258 if (ssh2_pkt_getuint32() != mainchan->localid) {
2259 bombout(("Server's channel confirmation cited wrong channel"));
2262 mainchan->remoteid = ssh2_pkt_getuint32();
2263 mainchan->u.v2.remwindow = ssh2_pkt_getuint32();
2264 mainchan->u.v2.remmaxpkt = ssh2_pkt_getuint32();
2265 mainchan->u.v2.outbuffer = NULL;
2266 mainchan->u.v2.outbuflen = mainchan->u.v2.outbufsize = 0;
2267 logevent("Opened channel for session");
2270 * Now allocate a pty for the session.
2273 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
2274 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
2275 ssh2_pkt_addstring("pty-req");
2276 ssh2_pkt_addbool(1); /* want reply */
2277 ssh2_pkt_addstring(cfg.termtype);
2278 ssh2_pkt_adduint32(cols);
2279 ssh2_pkt_adduint32(rows);
2280 ssh2_pkt_adduint32(0); /* pixel width */
2281 ssh2_pkt_adduint32(0); /* pixel height */
2282 ssh2_pkt_addstring_start();
2283 ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
2287 crWaitUntilV(ispkt);
2288 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2289 /* FIXME: be able to handle other channels here */
2290 if (ssh2_pkt_getuint32() != mainchan->localid)
2291 continue; /* wrong channel */
2292 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2294 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2296 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
2297 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
2298 bombout(("Server got confused by pty request"));
2301 c_write("Server refused to allocate pty\r\n", 32);
2303 logevent("Allocated pty");
2308 * Start a shell or a remote command.
2310 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
2311 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
2312 if (*cfg.remote_cmd) {
2313 ssh2_pkt_addstring("exec");
2314 ssh2_pkt_addbool(1); /* want reply */
2315 ssh2_pkt_addstring(cfg.remote_cmd);
2317 ssh2_pkt_addstring("shell");
2318 ssh2_pkt_addbool(1); /* want reply */
2322 crWaitUntilV(ispkt);
2323 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2324 /* FIXME: be able to handle other channels here */
2325 if (ssh2_pkt_getuint32() != mainchan->localid)
2326 continue; /* wrong channel */
2327 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2329 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2330 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
2331 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
2332 bombout(("Server got confused by shell/command request"));
2335 bombout(("Server refused to start a shell/command"));
2338 logevent("Started a shell/command");
2347 static int try_send;
2351 if (pktin.type == SSH2_MSG_CHANNEL_DATA ||
2352 pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
2355 /* FIXME: be able to handle other channels here */
2356 if (ssh2_pkt_getuint32() != mainchan->localid)
2357 continue; /* wrong channel */
2358 if (pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
2359 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR)
2360 continue; /* extended but not stderr */
2361 ssh2_pkt_getstring(&data, &length);
2363 c_write(data, length);
2365 * Enlarge the window again at the remote side,
2366 * just in case it ever runs down and they fail
2367 * to send us any more data.
2369 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2370 ssh2_pkt_adduint32(mainchan->remoteid);
2371 ssh2_pkt_adduint32(length);
2374 } else if (pktin.type == SSH2_MSG_DISCONNECT) {
2375 ssh_state = SSH_STATE_CLOSED;
2376 logevent("Received disconnect message");
2377 } else if (pktin.type == SSH2_MSG_CHANNEL_REQUEST) {
2378 continue; /* exit status et al; ignore (FIXME?) */
2379 } else if (pktin.type == SSH2_MSG_CHANNEL_EOF) {
2380 continue; /* remote sends EOF; ignore */
2381 } else if (pktin.type == SSH2_MSG_CHANNEL_CLOSE) {
2382 /* FIXME: be able to handle other channels here */
2383 if (ssh2_pkt_getuint32() != mainchan->localid)
2384 continue; /* wrong channel */
2385 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
2386 ssh2_pkt_adduint32(mainchan->remoteid);
2388 /* FIXME: mark the channel as closed */
2389 if (1 /* FIXME: "all channels are closed" */) {
2390 logevent("All channels closed. Disconnecting");
2391 ssh2_pkt_init(SSH2_MSG_DISCONNECT);
2394 continue; /* remote sends close; ignore (FIXME) */
2395 } else if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2396 /* FIXME: be able to handle other channels here */
2397 if (ssh2_pkt_getuint32() != mainchan->localid)
2398 continue; /* wrong channel */
2399 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2402 bombout(("Strange packet received: type %d", pktin.type));
2407 * We have spare data. Add it to the channel buffer.
2409 if (mainchan->u.v2.outbufsize <
2410 mainchan->u.v2.outbuflen + inlen) {
2411 mainchan->u.v2.outbufsize =
2412 mainchan->u.v2.outbuflen + inlen + 1024;
2413 mainchan->u.v2.outbuffer = srealloc(mainchan->u.v2.outbuffer,
2414 mainchan->u.v2.outbufsize);
2416 memcpy(mainchan->u.v2.outbuffer + mainchan->u.v2.outbuflen,
2418 mainchan->u.v2.outbuflen += inlen;
2423 * Try to send data on the channel if we can. (FIXME:
2424 * on _all_ channels.)
2426 while (mainchan->u.v2.remwindow > 0 &&
2427 mainchan->u.v2.outbuflen > 0) {
2428 unsigned len = mainchan->u.v2.remwindow;
2429 if (len > mainchan->u.v2.outbuflen)
2430 len = mainchan->u.v2.outbuflen;
2431 if (len > mainchan->u.v2.remmaxpkt)
2432 len = mainchan->u.v2.remmaxpkt;
2433 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
2434 ssh2_pkt_adduint32(mainchan->remoteid);
2435 ssh2_pkt_addstring_start();
2436 ssh2_pkt_addstring_data(mainchan->u.v2.outbuffer, len);
2438 mainchan->u.v2.outbuflen -= len;
2439 memmove(mainchan->u.v2.outbuffer, mainchan->u.v2.outbuffer+len,
2440 mainchan->u.v2.outbuflen);
2441 mainchan->u.v2.remwindow -= len;
2450 * Handle the top-level SSH2 protocol.
2452 static void ssh2_protocol(unsigned char *in, int inlen, int ispkt)
2454 if (do_ssh2_transport(in, inlen, ispkt) == 0)
2456 do_ssh2_authconn(in, inlen, ispkt);
2460 * Called to set up the connection. Will arrange for WM_NETEVENT
2461 * messages to be passed to the specified window, whose window
2462 * procedure should then call telnet_msg().
2464 * Returns an error message, or NULL on success.
2466 static char *ssh_init (HWND hwnd, char *host, int port, char **realhost) {
2470 if(crypto_startup() == 0)
2471 return "Microsoft high encryption pack not installed!";
2474 p = connect_to_host(host, port, realhost);
2479 return "Protocol initialisation error";
2481 if (hwnd && WSAAsyncSelect (s, hwnd, WM_NETEVENT, FD_READ | FD_CLOSE) == SOCKET_ERROR)
2482 switch (WSAGetLastError()) {
2483 case WSAENETDOWN: return "Network is down";
2484 default: return "WSAAsyncSelect(): unknown error";
2491 * Process a WM_NETEVENT message. Will return 0 if the connection
2492 * has closed, or <0 for a socket error.
2494 static int ssh_msg (WPARAM wParam, LPARAM lParam) {
2499 * Because reading less than the whole of the available pending
2500 * data can generate an FD_READ event, we need to allow for the
2501 * possibility that FD_READ may arrive with FD_CLOSE already in
2502 * the queue; so it's possible that we can get here even with s
2503 * invalid. If so, we return 1 and don't worry about it.
2505 if (s == INVALID_SOCKET)
2508 if (WSAGETSELECTERROR(lParam) != 0) {
2511 return -WSAGETSELECTERROR(lParam);
2514 switch (WSAGETSELECTEVENT(lParam)) {
2517 ret = recv(s, buf, sizeof(buf), 0);
2518 if (ret < 0 && WSAGetLastError() == WSAEWOULDBLOCK)
2520 if (ret < 0) { /* any _other_ error */
2523 return -10000-WSAGetLastError();
2529 ssh_gotdata (buf, ret);
2530 if (ssh_state == SSH_STATE_CLOSED) {
2537 return 1; /* shouldn't happen, but WTF */
2541 * Called to send data down the Telnet connection.
2543 static void ssh_send (char *buf, int len) {
2544 if (s == INVALID_SOCKET)
2547 ssh_protocol(buf, len, 0);
2551 * Called to set the size of the window from Telnet's POV.
2553 static void ssh_size(void) {
2554 switch (ssh_state) {
2555 case SSH_STATE_BEFORE_SIZE:
2556 case SSH_STATE_CLOSED:
2557 break; /* do nothing */
2558 case SSH_STATE_INTERMED:
2559 size_needed = TRUE; /* buffer for later */
2561 case SSH_STATE_SESSION:
2563 send_packet(SSH1_CMSG_WINDOW_SIZE,
2564 PKT_INT, rows, PKT_INT, cols,
2565 PKT_INT, 0, PKT_INT, 0, PKT_END);
2571 * Send Telnet special codes. TS_EOF is useful for `plink', so you
2572 * can send an EOF and collect resulting output (e.g. `plink
2575 static void ssh_special (Telnet_Special code) {
2576 if (code == TS_EOF) {
2577 if (ssh_version == 1) {
2578 send_packet(SSH1_CMSG_EOF, PKT_END);
2580 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
2581 ssh2_pkt_adduint32(mainchan->remoteid);
2584 logevent("Sent EOF message");
2592 * Read and decrypt one incoming SSH packet.
2593 * (only used by pSCP)
2595 static void get_packet(void)
2597 unsigned char buf[4096], *p;
2604 while ((to_read = s_rdpkt(&p, &len)) > 0) {
2605 if (to_read > sizeof(buf)) to_read = sizeof(buf);
2606 len = s_read(buf, to_read);
2607 if (len != to_read) {
2619 * Receive a block of data over the SSH link. Block until
2620 * all data is available. Return nr of bytes read (0 if lost connection).
2621 * (only used by pSCP)
2623 int ssh_scp_recv(unsigned char *buf, int len)
2625 static int pending_input_len = 0;
2626 static unsigned char *pending_input_ptr;
2629 if (pending_input_len >= to_read) {
2630 memcpy(buf, pending_input_ptr, to_read);
2631 pending_input_ptr += to_read;
2632 pending_input_len -= to_read;
2636 if (pending_input_len > 0) {
2637 memcpy(buf, pending_input_ptr, pending_input_len);
2638 buf += pending_input_len;
2639 to_read -= pending_input_len;
2640 pending_input_len = 0;
2643 if (s == INVALID_SOCKET)
2645 while (to_read > 0) {
2647 if (s == INVALID_SOCKET)
2649 if (pktin.type == SSH1_SMSG_STDOUT_DATA) {
2650 int plen = GET_32BIT(pktin.body);
2651 if (plen <= to_read) {
2652 memcpy(buf, pktin.body + 4, plen);
2656 memcpy(buf, pktin.body + 4, to_read);
2657 pending_input_len = plen - to_read;
2658 pending_input_ptr = pktin.body + 4 + to_read;
2661 } else if (pktin.type == SSH1_SMSG_STDERR_DATA) {
2662 int plen = GET_32BIT(pktin.body);
2663 fwrite(pktin.body + 4, plen, 1, stderr);
2664 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
2665 logevent("Received disconnect request");
2666 } else if (pktin.type == SSH1_SMSG_SUCCESS ||
2667 pktin.type == SSH1_SMSG_FAILURE) {
2669 } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) {
2671 sprintf(logbuf, "Remote exit status: %d", GET_32BIT(pktin.body));
2673 send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
2674 logevent("Closing connection");
2678 bombout(("Strange packet received: type %d", pktin.type));
2687 * Send a block of data over the SSH link.
2688 * Block until all data is sent.
2689 * (only used by pSCP)
2691 void ssh_scp_send(unsigned char *buf, int len)
2693 if (s == INVALID_SOCKET)
2695 send_packet(SSH1_CMSG_STDIN_DATA,
2696 PKT_INT, len, PKT_DATA, buf, len, PKT_END);
2700 * Send an EOF notification to the server.
2701 * (only used by pSCP)
2703 void ssh_scp_send_eof(void)
2705 if (s == INVALID_SOCKET)
2707 send_packet(SSH1_CMSG_EOF, PKT_END);
2711 * Set up the connection, login on the remote host and
2712 * start execution of a command.
2713 * Returns an error message, or NULL on success.
2714 * (only used by pSCP)
2716 char *ssh_scp_init(char *host, int port, char *cmd, char **realhost)
2721 if (crypto_startup() == 0)
2722 return "Microsoft high encryption pack not installed!";
2725 p = connect_to_host(host, port, realhost);
2732 return "Protocol initialisation error";
2734 /* Exchange keys and login */
2737 if (s == INVALID_SOCKET)
2738 return "Connection closed by remote host";
2739 } while (!do_ssh1_login(NULL, 0, 1));
2741 if (ssh_state == SSH_STATE_CLOSED) {
2744 return "Session initialisation error";
2747 /* Execute command */
2748 sprintf(buf, "Sending command: %.100s", cmd);
2750 send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
2755 static SOCKET ssh_socket(void) { return s; }
2757 static int ssh_sendok(void) { return ssh_send_ok; }
2759 Backend ssh_backend = {