374330e2 |
1 | #include <stdio.h> |
2 | #include <stdlib.h> |
fb09bf1c |
3 | #include <stdarg.h> |
4 | #include <assert.h> |
4d331a77 |
5 | #ifndef AUTO_WINSOCK |
6 | #ifdef WINSOCK_TWO |
7 | #include <winsock2.h> |
8 | #else |
374330e2 |
9 | #include <winsock.h> |
4d331a77 |
10 | #endif |
11 | #endif |
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12 | |
13 | #include "putty.h" |
dacbd0e8 |
14 | #include "tree234.h" |
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15 | #include "ssh.h" |
374330e2 |
16 | |
17 | #ifndef FALSE |
18 | #define FALSE 0 |
19 | #endif |
20 | #ifndef TRUE |
21 | #define TRUE 1 |
22 | #endif |
23 | |
fb09bf1c |
24 | #define logevent(s) { logevent(s); \ |
67779be7 |
25 | if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \ |
fb09bf1c |
26 | fprintf(stderr, "%s\n", s); } |
27 | |
cf6e59d6 |
28 | #define bombout(msg) ( ssh_state = SSH_STATE_CLOSED, closesocket(s), \ |
8d5de777 |
29 | s = INVALID_SOCKET, connection_fatal msg ) |
30 | |
d211621f |
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 */ |
66 | |
67 | #define SSH1_AUTH_TIS 5 /* 0x5 */ |
68 | #define SSH1_AUTH_CCARD 16 /* 0x10 */ |
69 | |
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 */ |
78 | |
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 */ |
109 | |
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 */ |
114 | |
115 | #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */ |
fb09bf1c |
116 | |
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])) |
122 | |
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); } |
128 | |
7cca0d81 |
129 | enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM }; |
972a41c8 |
130 | |
374330e2 |
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) \ |
138 | do {\ |
139 | crLine=__LINE__; return (z); case __LINE__:;\ |
140 | } while (0) |
141 | #define crReturnV \ |
142 | do {\ |
143 | crLine=__LINE__; return; case __LINE__:;\ |
144 | } while (0) |
145 | #define crStop(z) do{ crLine = 0; return (z); }while(0) |
146 | #define crStopV do{ crLine = 0; return; }while(0) |
fb09bf1c |
147 | #define crWaitUntil(c) do { crReturn(0); } while (!(c)) |
7cca0d81 |
148 | #define crWaitUntilV(c) do { crReturnV; } while (!(c)) |
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149 | |
57476f6b |
150 | extern const struct ssh_cipher ssh_3des; |
151 | extern const struct ssh_cipher ssh_3des_ssh2; |
152 | extern const struct ssh_cipher ssh_des; |
153 | extern const struct ssh_cipher ssh_blowfish_ssh1; |
154 | extern const struct ssh_cipher ssh_blowfish_ssh2; |
e5574168 |
155 | |
5e8358ad |
156 | /* |
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.) |
5e8358ad |
161 | */ |
57476f6b |
162 | const static struct ssh_cipher *ciphers[] = { &ssh_blowfish_ssh2, &ssh_3des_ssh2 }; |
e5574168 |
163 | |
57476f6b |
164 | extern const struct ssh_kex ssh_diffiehellman; |
165 | const static struct ssh_kex *kex_algs[] = { &ssh_diffiehellman }; |
e5574168 |
166 | |
57476f6b |
167 | extern const struct ssh_hostkey ssh_dss; |
168 | const static struct ssh_hostkey *hostkey_algs[] = { &ssh_dss }; |
e5574168 |
169 | |
8b2715b2 |
170 | extern const struct ssh_mac ssh_md5, ssh_sha1, ssh_sha1_buggy; |
e5574168 |
171 | |
d39f364a |
172 | static void nullmac_key(unsigned char *key) { } |
e5574168 |
173 | static void nullmac_generate(unsigned char *blk, int len, unsigned long seq) { } |
174 | static int nullmac_verify(unsigned char *blk, int len, unsigned long seq) { return 1; } |
57476f6b |
175 | const static struct ssh_mac ssh_mac_none = { |
d39f364a |
176 | nullmac_key, nullmac_key, nullmac_generate, nullmac_verify, "none", 0 |
e5574168 |
177 | }; |
8b2715b2 |
178 | const static struct ssh_mac *macs[] = { |
179 | &ssh_sha1, &ssh_md5, &ssh_mac_none }; |
180 | const static struct ssh_mac *buggymacs[] = { |
181 | &ssh_sha1_buggy, &ssh_md5, &ssh_mac_none }; |
e5574168 |
182 | |
57476f6b |
183 | const static struct ssh_compress ssh_comp_none = { |
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184 | "none" |
185 | }; |
57476f6b |
186 | const static struct ssh_compress *compressions[] = { &ssh_comp_none }; |
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187 | |
dacbd0e8 |
188 | /* |
189 | * 2-3-4 tree storing channels. |
190 | */ |
191 | struct ssh_channel { |
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192 | unsigned remoteid, localid; |
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193 | int type; |
194 | int closes; |
195 | union { |
196 | struct ssh_agent_channel { |
197 | unsigned char *message; |
198 | unsigned char msglen[4]; |
199 | int lensofar, totallen; |
200 | } a; |
d211621f |
201 | struct ssh2_data_channel { |
202 | unsigned char *outbuffer; |
203 | unsigned outbuflen, outbufsize; |
204 | unsigned remwindow, remmaxpkt; |
205 | } v2; |
dacbd0e8 |
206 | } u; |
207 | }; |
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208 | |
209 | struct Packet { |
210 | long length; |
211 | int type; |
212 | unsigned char *data; |
213 | unsigned char *body; |
214 | long savedpos; |
215 | long maxlen; |
216 | }; |
217 | |
218 | static SHA_State exhash; |
219 | |
220 | static SOCKET s = INVALID_SOCKET; |
221 | |
222 | static unsigned char session_key[32]; |
223 | static const struct ssh_cipher *cipher = NULL; |
224 | static const struct ssh_cipher *cscipher = NULL; |
225 | static const struct ssh_cipher *sccipher = NULL; |
226 | static const struct ssh_mac *csmac = NULL; |
227 | static const struct ssh_mac *scmac = NULL; |
228 | static const struct ssh_compress *cscomp = NULL; |
229 | static const struct ssh_compress *sccomp = NULL; |
230 | static const struct ssh_kex *kex = NULL; |
231 | static const struct ssh_hostkey *hostkey = NULL; |
232 | int (*ssh_get_password)(const char *prompt, char *str, int maxlen) = NULL; |
233 | |
234 | static char *savedhost; |
235 | static int savedport; |
236 | static int ssh_send_ok; |
237 | |
dacbd0e8 |
238 | static tree234 *ssh_channels; /* indexed by local id */ |
57476f6b |
239 | static struct ssh_channel *mainchan; /* primary session channel */ |
240 | |
241 | static enum { |
242 | SSH_STATE_BEFORE_SIZE, |
243 | SSH_STATE_INTERMED, |
244 | SSH_STATE_SESSION, |
245 | SSH_STATE_CLOSED |
246 | } ssh_state = SSH_STATE_BEFORE_SIZE; |
247 | |
248 | static int size_needed = FALSE; |
249 | |
250 | static struct Packet pktin = { 0, 0, NULL, NULL, 0 }; |
251 | static struct Packet pktout = { 0, 0, NULL, NULL, 0 }; |
252 | |
253 | static int ssh_version; |
254 | static void (*ssh_protocol)(unsigned char *in, int inlen, int ispkt); |
255 | static void ssh1_protocol(unsigned char *in, int inlen, int ispkt); |
256 | static void ssh2_protocol(unsigned char *in, int inlen, int ispkt); |
257 | static void ssh_size(void); |
258 | |
259 | static int (*s_rdpkt)(unsigned char **data, int *datalen); |
260 | |
261 | static struct rdpkt1_state_tag { |
262 | long len, pad, biglen, to_read; |
263 | unsigned long realcrc, gotcrc; |
264 | unsigned char *p; |
265 | int i; |
266 | int chunk; |
267 | } rdpkt1_state; |
268 | |
960e736a |
269 | static struct rdpkt2_state_tag { |
270 | long len, pad, payload, packetlen, maclen; |
271 | int i; |
272 | int cipherblk; |
273 | unsigned long incoming_sequence; |
274 | } rdpkt2_state; |
275 | |
dacbd0e8 |
276 | static int ssh_channelcmp(void *av, void *bv) { |
277 | struct ssh_channel *a = (struct ssh_channel *)av; |
278 | struct ssh_channel *b = (struct ssh_channel *)bv; |
279 | if (a->localid < b->localid) return -1; |
280 | if (a->localid > b->localid) return +1; |
281 | return 0; |
282 | } |
283 | static int ssh_channelfind(void *av, void *bv) { |
d211621f |
284 | unsigned *a = (unsigned *)av; |
dacbd0e8 |
285 | struct ssh_channel *b = (struct ssh_channel *)bv; |
286 | if (*a < b->localid) return -1; |
287 | if (*a > b->localid) return +1; |
288 | return 0; |
289 | } |
290 | |
374330e2 |
291 | static void s_write (char *buf, int len) { |
292 | while (len > 0) { |
293 | int i = send (s, buf, len, 0); |
4017be6d |
294 | noise_ultralight(i); |
8d5de777 |
295 | if (i <= 0) { |
296 | bombout(("Lost connection while sending")); |
297 | return; |
298 | } |
374330e2 |
299 | if (i > 0) |
300 | len -= i, buf += i; |
301 | } |
302 | } |
303 | |
304 | static int s_read (char *buf, int len) { |
305 | int ret = 0; |
306 | while (len > 0) { |
307 | int i = recv (s, buf, len, 0); |
4017be6d |
308 | noise_ultralight(i); |
374330e2 |
309 | if (i > 0) |
310 | len -= i, buf += i, ret += i; |
311 | else |
312 | return i; |
313 | } |
314 | return ret; |
315 | } |
316 | |
317 | static void c_write (char *buf, int len) { |
67779be7 |
318 | if ((flags & FLAG_STDERR)) { |
4017be6d |
319 | int i; |
320 | for (i = 0; i < len; i++) |
321 | if (buf[i] != '\r') |
322 | fputc(buf[i], stderr); |
fb09bf1c |
323 | return; |
324 | } |
fe50e814 |
325 | from_backend(1, buf, len); |
3bdaf79d |
326 | } |
327 | |
fb09bf1c |
328 | /* |
329 | * Collect incoming data in the incoming packet buffer. |
e5574168 |
330 | * Decipher and verify the packet when it is completely read. |
331 | * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets. |
fb09bf1c |
332 | * Update the *data and *datalen variables. |
333 | * Return the additional nr of bytes needed, or 0 when |
334 | * a complete packet is available. |
335 | */ |
e5574168 |
336 | static int ssh1_rdpkt(unsigned char **data, int *datalen) |
fb09bf1c |
337 | { |
57476f6b |
338 | struct rdpkt1_state_tag *st = &rdpkt1_state; |
374330e2 |
339 | |
340 | crBegin; |
374330e2 |
341 | |
fb09bf1c |
342 | next_packet: |
37508af4 |
343 | |
fb09bf1c |
344 | pktin.type = 0; |
345 | pktin.length = 0; |
374330e2 |
346 | |
57476f6b |
347 | for (st->i = st->len = 0; st->i < 4; st->i++) { |
fb09bf1c |
348 | while ((*datalen) == 0) |
57476f6b |
349 | crReturn(4-st->i); |
350 | st->len = (st->len << 8) + **data; |
fb09bf1c |
351 | (*data)++, (*datalen)--; |
352 | } |
374330e2 |
353 | |
fb09bf1c |
354 | #ifdef FWHACK |
57476f6b |
355 | if (st->len == 0x52656d6f) { /* "Remo"te server has closed ... */ |
356 | st->len = 0x300; /* big enough to carry to end */ |
fb09bf1c |
357 | } |
358 | #endif |
374330e2 |
359 | |
57476f6b |
360 | st->pad = 8 - (st->len % 8); |
361 | st->biglen = st->len + st->pad; |
362 | pktin.length = st->len - 5; |
fb09bf1c |
363 | |
57476f6b |
364 | if (pktin.maxlen < st->biglen) { |
365 | pktin.maxlen = st->biglen; |
366 | pktin.data = (pktin.data == NULL ? malloc(st->biglen+APIEXTRA) : |
367 | realloc(pktin.data, st->biglen+APIEXTRA)); |
fb09bf1c |
368 | if (!pktin.data) |
369 | fatalbox("Out of memory"); |
370 | } |
374330e2 |
371 | |
57476f6b |
372 | st->to_read = st->biglen; |
373 | st->p = pktin.data; |
374 | while (st->to_read > 0) { |
375 | st->chunk = st->to_read; |
fb09bf1c |
376 | while ((*datalen) == 0) |
57476f6b |
377 | crReturn(st->to_read); |
378 | if (st->chunk > (*datalen)) |
379 | st->chunk = (*datalen); |
380 | memcpy(st->p, *data, st->chunk); |
381 | *data += st->chunk; |
382 | *datalen -= st->chunk; |
383 | st->p += st->chunk; |
384 | st->to_read -= st->chunk; |
fb09bf1c |
385 | } |
374330e2 |
386 | |
fb09bf1c |
387 | if (cipher) |
57476f6b |
388 | cipher->decrypt(pktin.data, st->biglen); |
698a5108 |
389 | #if 0 |
390 | debug(("Got packet len=%d pad=%d\r\n", st->len, st->pad)); |
391 | for (st->i = 0; st->i < st->biglen; st->i++) |
392 | debug((" %02x", (unsigned char)pktin.data[st->i])); |
393 | debug(("\r\n")); |
394 | #endif |
374330e2 |
395 | |
57476f6b |
396 | pktin.type = pktin.data[st->pad]; |
397 | pktin.body = pktin.data + st->pad + 1; |
374330e2 |
398 | |
57476f6b |
399 | st->realcrc = crc32(pktin.data, st->biglen-4); |
400 | st->gotcrc = GET_32BIT(pktin.data+st->biglen-4); |
401 | if (st->gotcrc != st->realcrc) { |
8d5de777 |
402 | bombout(("Incorrect CRC received on packet")); |
403 | crReturn(0); |
fb09bf1c |
404 | } |
572f871e |
405 | |
e5574168 |
406 | if (pktin.type == SSH1_SMSG_STDOUT_DATA || |
407 | pktin.type == SSH1_SMSG_STDERR_DATA || |
408 | pktin.type == SSH1_MSG_DEBUG || |
18515c51 |
409 | pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE || |
410 | pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) { |
fb09bf1c |
411 | long strlen = GET_32BIT(pktin.body); |
8d5de777 |
412 | if (strlen + 4 != pktin.length) { |
413 | bombout(("Received data packet with bogus string length")); |
414 | crReturn(0); |
415 | } |
fb09bf1c |
416 | } |
417 | |
e5574168 |
418 | if (pktin.type == SSH1_MSG_DEBUG) { |
fb09bf1c |
419 | /* log debug message */ |
420 | char buf[80]; |
421 | int strlen = GET_32BIT(pktin.body); |
422 | strcpy(buf, "Remote: "); |
423 | if (strlen > 70) strlen = 70; |
424 | memcpy(buf+8, pktin.body+4, strlen); |
425 | buf[8+strlen] = '\0'; |
426 | logevent(buf); |
427 | goto next_packet; |
e5574168 |
428 | } else if (pktin.type == SSH1_MSG_IGNORE) { |
fb09bf1c |
429 | /* do nothing */ |
430 | goto next_packet; |
431 | } |
432 | |
433 | crFinish(0); |
434 | } |
435 | |
e5574168 |
436 | static int ssh2_rdpkt(unsigned char **data, int *datalen) |
437 | { |
960e736a |
438 | struct rdpkt2_state_tag *st = &rdpkt2_state; |
e5574168 |
439 | |
440 | crBegin; |
441 | |
442 | next_packet: |
e5574168 |
443 | pktin.type = 0; |
444 | pktin.length = 0; |
960e736a |
445 | if (sccipher) |
446 | st->cipherblk = sccipher->blksize; |
e5574168 |
447 | else |
960e736a |
448 | st->cipherblk = 8; |
449 | if (st->cipherblk < 8) |
450 | st->cipherblk = 8; |
451 | |
452 | if (pktin.maxlen < st->cipherblk) { |
453 | pktin.maxlen = st->cipherblk; |
454 | pktin.data = (pktin.data == NULL ? malloc(st->cipherblk+APIEXTRA) : |
455 | realloc(pktin.data, st->cipherblk+APIEXTRA)); |
e5574168 |
456 | if (!pktin.data) |
457 | fatalbox("Out of memory"); |
458 | } |
459 | |
460 | /* |
461 | * Acquire and decrypt the first block of the packet. This will |
462 | * contain the length and padding details. |
463 | */ |
960e736a |
464 | for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) { |
e5574168 |
465 | while ((*datalen) == 0) |
960e736a |
466 | crReturn(st->cipherblk-st->i); |
467 | pktin.data[st->i] = *(*data)++; |
e5574168 |
468 | (*datalen)--; |
469 | } |
470 | #ifdef FWHACK |
471 | if (!memcmp(pktin.data, "Remo", 4)) {/* "Remo"te server has closed ... */ |
472 | /* FIXME */ |
473 | } |
474 | #endif |
475 | if (sccipher) |
960e736a |
476 | sccipher->decrypt(pktin.data, st->cipherblk); |
e5574168 |
477 | |
478 | /* |
479 | * Now get the length and padding figures. |
480 | */ |
960e736a |
481 | st->len = GET_32BIT(pktin.data); |
482 | st->pad = pktin.data[4]; |
e5574168 |
483 | |
484 | /* |
485 | * This enables us to deduce the payload length. |
486 | */ |
960e736a |
487 | st->payload = st->len - st->pad - 1; |
e5574168 |
488 | |
960e736a |
489 | pktin.length = st->payload + 5; |
e5574168 |
490 | |
491 | /* |
492 | * So now we can work out the total packet length. |
493 | */ |
960e736a |
494 | st->packetlen = st->len + 4; |
495 | st->maclen = scmac ? scmac->len : 0; |
e5574168 |
496 | |
497 | /* |
498 | * Adjust memory allocation if packet is too big. |
499 | */ |
960e736a |
500 | if (pktin.maxlen < st->packetlen+st->maclen) { |
501 | pktin.maxlen = st->packetlen+st->maclen; |
59dcd2a8 |
502 | pktin.data = (pktin.data == NULL ? malloc(pktin.maxlen+APIEXTRA) : |
503 | realloc(pktin.data, pktin.maxlen+APIEXTRA)); |
e5574168 |
504 | if (!pktin.data) |
505 | fatalbox("Out of memory"); |
506 | } |
507 | |
508 | /* |
509 | * Read and decrypt the remainder of the packet. |
510 | */ |
960e736a |
511 | for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen; st->i++) { |
e5574168 |
512 | while ((*datalen) == 0) |
960e736a |
513 | crReturn(st->packetlen + st->maclen - st->i); |
514 | pktin.data[st->i] = *(*data)++; |
e5574168 |
515 | (*datalen)--; |
516 | } |
517 | /* Decrypt everything _except_ the MAC. */ |
518 | if (sccipher) |
960e736a |
519 | sccipher->decrypt(pktin.data + st->cipherblk, |
520 | st->packetlen - st->cipherblk); |
e5574168 |
521 | |
7cca0d81 |
522 | #if 0 |
960e736a |
523 | debug(("Got packet len=%d pad=%d\r\n", st->len, st->pad)); |
524 | for (st->i = 0; st->i < st->packetlen; st->i++) |
525 | debug((" %02x", (unsigned char)pktin.data[st->i])); |
d39f364a |
526 | debug(("\r\n")); |
7cca0d81 |
527 | #endif |
d39f364a |
528 | |
e5574168 |
529 | /* |
530 | * Check the MAC. |
531 | */ |
960e736a |
532 | if (scmac && !scmac->verify(pktin.data, st->len+4, st->incoming_sequence)) { |
8d5de777 |
533 | bombout(("Incorrect MAC received on packet")); |
534 | crReturn(0); |
535 | } |
960e736a |
536 | st->incoming_sequence++; /* whether or not we MACed */ |
e5574168 |
537 | |
538 | pktin.savedpos = 6; |
539 | pktin.type = pktin.data[5]; |
e5574168 |
540 | |
7cca0d81 |
541 | if (pktin.type == SSH2_MSG_IGNORE || pktin.type == SSH2_MSG_DEBUG) |
542 | goto next_packet; /* FIXME: print DEBUG message */ |
e5574168 |
543 | |
544 | crFinish(0); |
545 | } |
546 | |
fb09bf1c |
547 | static void ssh_gotdata(unsigned char *data, int datalen) |
548 | { |
549 | while (datalen > 0) { |
85ee8208 |
550 | if ( s_rdpkt(&data, &datalen) == 0 ) { |
374330e2 |
551 | ssh_protocol(NULL, 0, 1); |
85ee8208 |
552 | if (ssh_state == SSH_STATE_CLOSED) { |
553 | return; |
554 | } |
555 | } |
374330e2 |
556 | } |
374330e2 |
557 | } |
558 | |
fb09bf1c |
559 | |
374330e2 |
560 | static void s_wrpkt_start(int type, int len) { |
561 | int pad, biglen; |
562 | |
563 | len += 5; /* type and CRC */ |
564 | pad = 8 - (len%8); |
565 | biglen = len + pad; |
566 | |
567 | pktout.length = len-5; |
568 | if (pktout.maxlen < biglen) { |
569 | pktout.maxlen = biglen; |
8f203108 |
570 | #ifdef MSCRYPTOAPI |
fb09bf1c |
571 | /* Allocate enough buffer space for extra block |
8f203108 |
572 | * for MS CryptEncrypt() */ |
fb09bf1c |
573 | pktout.data = (pktout.data == NULL ? malloc(biglen+12) : |
574 | realloc(pktout.data, biglen+12)); |
8f203108 |
575 | #else |
c1f5f956 |
576 | pktout.data = (pktout.data == NULL ? malloc(biglen+4) : |
577 | realloc(pktout.data, biglen+4)); |
8f203108 |
578 | #endif |
374330e2 |
579 | if (!pktout.data) |
580 | fatalbox("Out of memory"); |
581 | } |
582 | |
583 | pktout.type = type; |
584 | pktout.body = pktout.data+4+pad+1; |
585 | } |
586 | |
587 | static void s_wrpkt(void) { |
588 | int pad, len, biglen, i; |
589 | unsigned long crc; |
590 | |
591 | len = pktout.length + 5; /* type and CRC */ |
592 | pad = 8 - (len%8); |
593 | biglen = len + pad; |
594 | |
595 | pktout.body[-1] = pktout.type; |
596 | for (i=0; i<pad; i++) |
597 | pktout.data[i+4] = random_byte(); |
598 | crc = crc32(pktout.data+4, biglen-4); |
fb09bf1c |
599 | PUT_32BIT(pktout.data+biglen, crc); |
600 | PUT_32BIT(pktout.data, len); |
374330e2 |
601 | |
698a5108 |
602 | #if 0 |
603 | debug(("Sending packet len=%d\r\n", biglen+4)); |
604 | for (i = 0; i < biglen+4; i++) |
605 | debug((" %02x", (unsigned char)pktout.data[i])); |
606 | debug(("\r\n")); |
607 | #endif |
374330e2 |
608 | if (cipher) |
609 | cipher->encrypt(pktout.data+4, biglen); |
610 | |
611 | s_write(pktout.data, biglen+4); |
612 | } |
613 | |
fb09bf1c |
614 | /* |
615 | * Construct a packet with the specified contents and |
616 | * send it to the server. |
617 | */ |
618 | static void send_packet(int pkttype, ...) |
619 | { |
620 | va_list args; |
621 | unsigned char *p, *argp, argchar; |
622 | unsigned long argint; |
623 | int pktlen, argtype, arglen; |
7cca0d81 |
624 | Bignum bn; |
fb09bf1c |
625 | |
626 | pktlen = 0; |
627 | va_start(args, pkttype); |
628 | while ((argtype = va_arg(args, int)) != PKT_END) { |
629 | switch (argtype) { |
630 | case PKT_INT: |
631 | (void) va_arg(args, int); |
632 | pktlen += 4; |
633 | break; |
634 | case PKT_CHAR: |
635 | (void) va_arg(args, char); |
636 | pktlen++; |
637 | break; |
638 | case PKT_DATA: |
639 | (void) va_arg(args, unsigned char *); |
640 | arglen = va_arg(args, int); |
641 | pktlen += arglen; |
642 | break; |
643 | case PKT_STR: |
644 | argp = va_arg(args, unsigned char *); |
645 | arglen = strlen(argp); |
646 | pktlen += 4 + arglen; |
647 | break; |
7cca0d81 |
648 | case PKT_BIGNUM: |
649 | bn = va_arg(args, Bignum); |
5c58ad2d |
650 | pktlen += ssh1_bignum_length(bn); |
7cca0d81 |
651 | break; |
fb09bf1c |
652 | default: |
653 | assert(0); |
654 | } |
655 | } |
656 | va_end(args); |
657 | |
658 | s_wrpkt_start(pkttype, pktlen); |
659 | p = pktout.body; |
660 | |
661 | va_start(args, pkttype); |
662 | while ((argtype = va_arg(args, int)) != PKT_END) { |
663 | switch (argtype) { |
664 | case PKT_INT: |
665 | argint = va_arg(args, int); |
666 | PUT_32BIT(p, argint); |
667 | p += 4; |
668 | break; |
669 | case PKT_CHAR: |
670 | argchar = va_arg(args, unsigned char); |
671 | *p = argchar; |
672 | p++; |
673 | break; |
674 | case PKT_DATA: |
675 | argp = va_arg(args, unsigned char *); |
676 | arglen = va_arg(args, int); |
677 | memcpy(p, argp, arglen); |
678 | p += arglen; |
679 | break; |
680 | case PKT_STR: |
681 | argp = va_arg(args, unsigned char *); |
682 | arglen = strlen(argp); |
683 | PUT_32BIT(p, arglen); |
684 | memcpy(p + 4, argp, arglen); |
685 | p += 4 + arglen; |
686 | break; |
7cca0d81 |
687 | case PKT_BIGNUM: |
688 | bn = va_arg(args, Bignum); |
5c58ad2d |
689 | p += ssh1_write_bignum(p, bn); |
7cca0d81 |
690 | break; |
fb09bf1c |
691 | } |
692 | } |
693 | va_end(args); |
694 | |
695 | s_wrpkt(); |
696 | } |
697 | |
698 | |
699 | /* |
700 | * Connect to specified host and port. |
701 | * Returns an error message, or NULL on success. |
702 | * Also places the canonical host name into `realhost'. |
703 | */ |
704 | static char *connect_to_host(char *host, int port, char **realhost) |
705 | { |
706 | SOCKADDR_IN addr; |
707 | struct hostent *h; |
708 | unsigned long a; |
709 | #ifdef FWHACK |
710 | char *FWhost; |
711 | int FWport; |
712 | #endif |
713 | |
714 | savedhost = malloc(1+strlen(host)); |
715 | if (!savedhost) |
716 | fatalbox("Out of memory"); |
717 | strcpy(savedhost, host); |
718 | |
719 | if (port < 0) |
720 | port = 22; /* default ssh port */ |
d4857987 |
721 | savedport = port; |
fb09bf1c |
722 | |
723 | #ifdef FWHACK |
724 | FWhost = host; |
725 | FWport = port; |
726 | host = FWSTR; |
727 | port = 23; |
728 | #endif |
729 | |
730 | /* |
731 | * Try to find host. |
732 | */ |
733 | if ( (a = inet_addr(host)) == (unsigned long) INADDR_NONE) { |
734 | if ( (h = gethostbyname(host)) == NULL) |
735 | switch (WSAGetLastError()) { |
736 | case WSAENETDOWN: return "Network is down"; |
737 | case WSAHOST_NOT_FOUND: case WSANO_DATA: |
738 | return "Host does not exist"; |
739 | case WSATRY_AGAIN: return "Host not found"; |
740 | default: return "gethostbyname: unknown error"; |
741 | } |
742 | memcpy (&a, h->h_addr, sizeof(a)); |
743 | *realhost = h->h_name; |
744 | } else |
745 | *realhost = host; |
746 | #ifdef FWHACK |
747 | *realhost = FWhost; |
748 | #endif |
749 | a = ntohl(a); |
750 | |
751 | /* |
752 | * Open socket. |
753 | */ |
754 | s = socket(AF_INET, SOCK_STREAM, 0); |
755 | if (s == INVALID_SOCKET) |
756 | switch (WSAGetLastError()) { |
757 | case WSAENETDOWN: return "Network is down"; |
758 | case WSAEAFNOSUPPORT: return "TCP/IP support not present"; |
759 | default: return "socket(): unknown error"; |
760 | } |
761 | |
762 | /* |
763 | * Bind to local address. |
764 | */ |
765 | addr.sin_family = AF_INET; |
766 | addr.sin_addr.s_addr = htonl(INADDR_ANY); |
767 | addr.sin_port = htons(0); |
768 | if (bind (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR) |
769 | switch (WSAGetLastError()) { |
770 | case WSAENETDOWN: return "Network is down"; |
771 | default: return "bind(): unknown error"; |
772 | } |
773 | |
774 | /* |
775 | * Connect to remote address. |
776 | */ |
777 | addr.sin_addr.s_addr = htonl(a); |
778 | addr.sin_port = htons((short)port); |
779 | if (connect (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR) |
780 | switch (WSAGetLastError()) { |
781 | case WSAENETDOWN: return "Network is down"; |
782 | case WSAECONNREFUSED: return "Connection refused"; |
783 | case WSAENETUNREACH: return "Network is unreachable"; |
784 | case WSAEHOSTUNREACH: return "No route to host"; |
785 | default: return "connect(): unknown error"; |
786 | } |
787 | |
788 | #ifdef FWHACK |
789 | send(s, "connect ", 8, 0); |
790 | send(s, FWhost, strlen(FWhost), 0); |
791 | { |
792 | char buf[20]; |
793 | sprintf(buf, " %d\n", FWport); |
794 | send (s, buf, strlen(buf), 0); |
795 | } |
796 | #endif |
797 | |
798 | return NULL; |
799 | } |
800 | |
9697bfd2 |
801 | static int ssh_versioncmp(char *a, char *b) { |
802 | char *ae, *be; |
803 | unsigned long av, bv; |
804 | |
43aa02a7 |
805 | av = strtoul(a, &ae, 10); |
806 | bv = strtoul(b, &be, 10); |
9697bfd2 |
807 | if (av != bv) return (av < bv ? -1 : +1); |
808 | if (*ae == '.') ae++; |
809 | if (*be == '.') be++; |
43aa02a7 |
810 | av = strtoul(ae, &ae, 10); |
811 | bv = strtoul(be, &be, 10); |
9697bfd2 |
812 | if (av != bv) return (av < bv ? -1 : +1); |
813 | return 0; |
814 | } |
815 | |
e5574168 |
816 | |
817 | /* |
818 | * Utility routine for putting an SSH-protocol `string' into a SHA |
819 | * state. |
820 | */ |
821 | #include <stdio.h> |
75cab814 |
822 | static void sha_string(SHA_State *s, void *str, int len) { |
e5574168 |
823 | unsigned char lenblk[4]; |
e5574168 |
824 | PUT_32BIT(lenblk, len); |
e5574168 |
825 | SHA_Bytes(s, lenblk, 4); |
e5574168 |
826 | SHA_Bytes(s, str, len); |
827 | } |
828 | |
7cca0d81 |
829 | /* |
830 | * SSH2 packet construction functions. |
831 | */ |
75cab814 |
832 | static void ssh2_pkt_adddata(void *data, int len) { |
7cca0d81 |
833 | pktout.length += len; |
834 | if (pktout.maxlen < pktout.length) { |
835 | pktout.maxlen = pktout.length + 256; |
836 | pktout.data = (pktout.data == NULL ? malloc(pktout.maxlen+APIEXTRA) : |
837 | realloc(pktout.data, pktout.maxlen+APIEXTRA)); |
838 | if (!pktout.data) |
839 | fatalbox("Out of memory"); |
840 | } |
841 | memcpy(pktout.data+pktout.length-len, data, len); |
842 | } |
75cab814 |
843 | static void ssh2_pkt_addbyte(unsigned char byte) { |
7cca0d81 |
844 | ssh2_pkt_adddata(&byte, 1); |
845 | } |
75cab814 |
846 | static void ssh2_pkt_init(int pkt_type) { |
7cca0d81 |
847 | pktout.length = 5; |
848 | ssh2_pkt_addbyte((unsigned char)pkt_type); |
849 | } |
75cab814 |
850 | static void ssh2_pkt_addbool(unsigned char value) { |
7cca0d81 |
851 | ssh2_pkt_adddata(&value, 1); |
852 | } |
75cab814 |
853 | static void ssh2_pkt_adduint32(unsigned long value) { |
7cca0d81 |
854 | unsigned char x[4]; |
855 | PUT_32BIT(x, value); |
856 | ssh2_pkt_adddata(x, 4); |
857 | } |
75cab814 |
858 | static void ssh2_pkt_addstring_start(void) { |
7cca0d81 |
859 | ssh2_pkt_adduint32(0); |
860 | pktout.savedpos = pktout.length; |
861 | } |
75cab814 |
862 | static void ssh2_pkt_addstring_str(char *data) { |
7cca0d81 |
863 | ssh2_pkt_adddata(data, strlen(data)); |
864 | PUT_32BIT(pktout.data + pktout.savedpos - 4, |
865 | pktout.length - pktout.savedpos); |
866 | } |
75cab814 |
867 | static void ssh2_pkt_addstring_data(char *data, int len) { |
7cca0d81 |
868 | ssh2_pkt_adddata(data, len); |
869 | PUT_32BIT(pktout.data + pktout.savedpos - 4, |
870 | pktout.length - pktout.savedpos); |
871 | } |
75cab814 |
872 | static void ssh2_pkt_addstring(char *data) { |
7cca0d81 |
873 | ssh2_pkt_addstring_start(); |
874 | ssh2_pkt_addstring_str(data); |
875 | } |
75cab814 |
876 | static char *ssh2_mpint_fmt(Bignum b, int *len) { |
7cca0d81 |
877 | unsigned char *p; |
878 | int i, n = b[0]; |
879 | p = malloc(n * 2 + 1); |
880 | if (!p) |
881 | fatalbox("out of memory"); |
882 | p[0] = 0; |
883 | for (i = 0; i < n; i++) { |
884 | p[i*2+1] = (b[n-i] >> 8) & 0xFF; |
885 | p[i*2+2] = (b[n-i] ) & 0xFF; |
886 | } |
887 | i = 0; |
888 | while (p[i] == 0 && (p[i+1] & 0x80) == 0) |
889 | i++; |
890 | memmove(p, p+i, n*2+1-i); |
891 | *len = n*2+1-i; |
892 | return p; |
893 | } |
75cab814 |
894 | static void ssh2_pkt_addmp(Bignum b) { |
7cca0d81 |
895 | unsigned char *p; |
896 | int len; |
897 | p = ssh2_mpint_fmt(b, &len); |
898 | ssh2_pkt_addstring_start(); |
899 | ssh2_pkt_addstring_data(p, len); |
900 | free(p); |
901 | } |
75cab814 |
902 | static void ssh2_pkt_send(void) { |
7cca0d81 |
903 | int cipherblk, maclen, padding, i; |
904 | static unsigned long outgoing_sequence = 0; |
905 | |
906 | /* |
907 | * Add padding. At least four bytes, and must also bring total |
908 | * length (minus MAC) up to a multiple of the block size. |
909 | */ |
910 | cipherblk = cipher ? cipher->blksize : 8; /* block size */ |
911 | cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */ |
912 | padding = 4; |
913 | padding += (cipherblk - (pktout.length + padding) % cipherblk) % cipherblk; |
914 | pktout.data[4] = padding; |
915 | for (i = 0; i < padding; i++) |
916 | pktout.data[pktout.length + i] = random_byte(); |
917 | PUT_32BIT(pktout.data, pktout.length + padding - 4); |
918 | if (csmac) |
919 | csmac->generate(pktout.data, pktout.length + padding, |
920 | outgoing_sequence); |
921 | outgoing_sequence++; /* whether or not we MACed */ |
922 | |
923 | #if 0 |
924 | debug(("Sending packet len=%d\r\n", pktout.length+padding)); |
925 | for (i = 0; i < pktout.length+padding; i++) |
926 | debug((" %02x", (unsigned char)pktout.data[i])); |
927 | debug(("\r\n")); |
928 | #endif |
929 | |
930 | if (cscipher) |
931 | cscipher->encrypt(pktout.data, pktout.length + padding); |
932 | maclen = csmac ? csmac->len : 0; |
933 | |
934 | s_write(pktout.data, pktout.length + padding + maclen); |
935 | } |
936 | |
937 | #if 0 |
938 | void bndebug(char *string, Bignum b) { |
939 | unsigned char *p; |
940 | int i, len; |
941 | p = ssh2_mpint_fmt(b, &len); |
942 | debug(("%s", string)); |
943 | for (i = 0; i < len; i++) |
944 | debug((" %02x", p[i])); |
945 | debug(("\r\n")); |
946 | free(p); |
947 | } |
948 | #endif |
949 | |
75cab814 |
950 | static void sha_mpint(SHA_State *s, Bignum b) { |
7cca0d81 |
951 | unsigned char *p; |
952 | int len; |
953 | p = ssh2_mpint_fmt(b, &len); |
954 | sha_string(s, p, len); |
955 | free(p); |
956 | } |
957 | |
958 | /* |
959 | * SSH2 packet decode functions. |
960 | */ |
75cab814 |
961 | static unsigned long ssh2_pkt_getuint32(void) { |
7cca0d81 |
962 | unsigned long value; |
963 | if (pktin.length - pktin.savedpos < 4) |
964 | return 0; /* arrgh, no way to decline (FIXME?) */ |
965 | value = GET_32BIT(pktin.data+pktin.savedpos); |
966 | pktin.savedpos += 4; |
967 | return value; |
968 | } |
75cab814 |
969 | static void ssh2_pkt_getstring(char **p, int *length) { |
7cca0d81 |
970 | *p = NULL; |
971 | if (pktin.length - pktin.savedpos < 4) |
972 | return; |
973 | *length = GET_32BIT(pktin.data+pktin.savedpos); |
974 | pktin.savedpos += 4; |
975 | if (pktin.length - pktin.savedpos < *length) |
976 | return; |
977 | *p = pktin.data+pktin.savedpos; |
978 | pktin.savedpos += *length; |
979 | } |
75cab814 |
980 | static Bignum ssh2_pkt_getmp(void) { |
7cca0d81 |
981 | char *p; |
982 | int i, j, length; |
983 | Bignum b; |
984 | |
985 | ssh2_pkt_getstring(&p, &length); |
986 | if (!p) |
987 | return NULL; |
8d5de777 |
988 | if (p[0] & 0x80) { |
989 | bombout(("internal error: Can't handle negative mpints")); |
990 | return NULL; |
991 | } |
7cca0d81 |
992 | b = newbn((length+1)/2); |
993 | for (i = 0; i < length; i++) { |
994 | j = length - 1 - i; |
995 | if (j & 1) |
996 | b[j/2+1] |= ((unsigned char)p[i]) << 8; |
997 | else |
998 | b[j/2+1] |= ((unsigned char)p[i]); |
999 | } |
1000 | return b; |
1001 | } |
1002 | |
374330e2 |
1003 | static int do_ssh_init(void) { |
c5e9c988 |
1004 | char c, *vsp; |
374330e2 |
1005 | char version[10]; |
c5e9c988 |
1006 | char vstring[80]; |
1007 | char vlog[sizeof(vstring)+20]; |
374330e2 |
1008 | int i; |
1009 | |
1010 | #ifdef FWHACK |
1011 | i = 0; |
1012 | while (s_read(&c, 1) == 1) { |
1013 | if (c == 'S' && i < 2) i++; |
1014 | else if (c == 'S' && i == 2) i = 2; |
1015 | else if (c == 'H' && i == 2) break; |
1016 | else i = 0; |
1017 | } |
1018 | #else |
1019 | if (s_read(&c,1) != 1 || c != 'S') return 0; |
1020 | if (s_read(&c,1) != 1 || c != 'S') return 0; |
1021 | if (s_read(&c,1) != 1 || c != 'H') return 0; |
1022 | #endif |
c5e9c988 |
1023 | strcpy(vstring, "SSH-"); |
1024 | vsp = vstring+4; |
374330e2 |
1025 | if (s_read(&c,1) != 1 || c != '-') return 0; |
1026 | i = 0; |
1027 | while (1) { |
1028 | if (s_read(&c,1) != 1) |
1029 | return 0; |
c5e9c988 |
1030 | if (vsp < vstring+sizeof(vstring)-1) |
1031 | *vsp++ = c; |
374330e2 |
1032 | if (i >= 0) { |
1033 | if (c == '-') { |
1034 | version[i] = '\0'; |
1035 | i = -1; |
1036 | } else if (i < sizeof(version)-1) |
1037 | version[i++] = c; |
1038 | } |
1039 | else if (c == '\n') |
1040 | break; |
1041 | } |
1042 | |
960e736a |
1043 | rdpkt2_state.incoming_sequence = 0; |
1044 | |
c5e9c988 |
1045 | *vsp = 0; |
1046 | sprintf(vlog, "Server version: %s", vstring); |
1047 | vlog[strcspn(vlog, "\r\n")] = '\0'; |
1048 | logevent(vlog); |
1049 | |
adf799dd |
1050 | /* |
1051 | * Server version "1.99" means we can choose whether we use v1 |
1052 | * or v2 protocol. Choice is based on cfg.sshprot. |
1053 | */ |
1054 | if (ssh_versioncmp(version, cfg.sshprot == 1 ? "2.0" : "1.99") >= 0) { |
e5574168 |
1055 | /* |
1056 | * This is a v2 server. Begin v2 protocol. |
1057 | */ |
1058 | char *verstring = "SSH-2.0-PuTTY"; |
1059 | SHA_Init(&exhash); |
1060 | /* |
1061 | * Hash our version string and their version string. |
1062 | */ |
1063 | sha_string(&exhash, verstring, strlen(verstring)); |
1064 | sha_string(&exhash, vstring, strcspn(vstring, "\r\n")); |
1065 | sprintf(vstring, "%s\n", verstring); |
1066 | sprintf(vlog, "We claim version: %s", verstring); |
1067 | logevent(vlog); |
1068 | logevent("Using SSH protocol version 2"); |
1069 | s_write(vstring, strlen(vstring)); |
1070 | ssh_protocol = ssh2_protocol; |
6abbf9e3 |
1071 | ssh_version = 2; |
e5574168 |
1072 | s_rdpkt = ssh2_rdpkt; |
1073 | } else { |
1074 | /* |
1075 | * This is a v1 server. Begin v1 protocol. |
1076 | */ |
1077 | sprintf(vstring, "SSH-%s-PuTTY\n", |
1078 | (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5")); |
1079 | sprintf(vlog, "We claim version: %s", vstring); |
1080 | vlog[strcspn(vlog, "\r\n")] = '\0'; |
1081 | logevent(vlog); |
1082 | logevent("Using SSH protocol version 1"); |
1083 | s_write(vstring, strlen(vstring)); |
1084 | ssh_protocol = ssh1_protocol; |
6abbf9e3 |
1085 | ssh_version = 1; |
e5574168 |
1086 | s_rdpkt = ssh1_rdpkt; |
1087 | } |
8ccc75b0 |
1088 | ssh_send_ok = 0; |
fef97f43 |
1089 | return 1; |
374330e2 |
1090 | } |
1091 | |
fb09bf1c |
1092 | /* |
1093 | * Handle the key exchange and user authentication phases. |
1094 | */ |
e5574168 |
1095 | static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) |
fb09bf1c |
1096 | { |
374330e2 |
1097 | int i, j, len; |
374330e2 |
1098 | unsigned char *rsabuf, *keystr1, *keystr2; |
1099 | unsigned char cookie[8]; |
1100 | struct RSAKey servkey, hostkey; |
1101 | struct MD5Context md5c; |
ccbfb941 |
1102 | static unsigned long supported_ciphers_mask, supported_auths_mask; |
7cca0d81 |
1103 | static int tried_publickey; |
1104 | static unsigned char session_id[16]; |
bea1ef5f |
1105 | int cipher_type; |
b585ec46 |
1106 | static char username[100]; |
374330e2 |
1107 | |
374330e2 |
1108 | crBegin; |
1109 | |
fb09bf1c |
1110 | if (!ispkt) crWaitUntil(ispkt); |
374330e2 |
1111 | |
8d5de777 |
1112 | if (pktin.type != SSH1_SMSG_PUBLIC_KEY) { |
1113 | bombout(("Public key packet not received")); |
1114 | crReturn(0); |
1115 | } |
374330e2 |
1116 | |
c5e9c988 |
1117 | logevent("Received public keys"); |
374330e2 |
1118 | |
c5e9c988 |
1119 | memcpy(cookie, pktin.body, 8); |
374330e2 |
1120 | |
7cca0d81 |
1121 | i = makekey(pktin.body+8, &servkey, &keystr1, 0); |
1122 | j = makekey(pktin.body+8+i, &hostkey, &keystr2, 0); |
374330e2 |
1123 | |
c5e9c988 |
1124 | /* |
1c2a93c4 |
1125 | * Log the host key fingerprint. |
c5e9c988 |
1126 | */ |
c5e9c988 |
1127 | { |
1128 | char logmsg[80]; |
1c2a93c4 |
1129 | logevent("Host key fingerprint is:"); |
c5e9c988 |
1130 | strcpy(logmsg, " "); |
1c2a93c4 |
1131 | hostkey.comment = NULL; |
1132 | rsa_fingerprint(logmsg+strlen(logmsg), sizeof(logmsg)-strlen(logmsg), |
1133 | &hostkey); |
c5e9c988 |
1134 | logevent(logmsg); |
1135 | } |
1136 | |
fb09bf1c |
1137 | supported_ciphers_mask = GET_32BIT(pktin.body+12+i+j); |
1138 | supported_auths_mask = GET_32BIT(pktin.body+16+i+j); |
bea1ef5f |
1139 | |
c5e9c988 |
1140 | MD5Init(&md5c); |
374330e2 |
1141 | MD5Update(&md5c, keystr2, hostkey.bytes); |
1142 | MD5Update(&md5c, keystr1, servkey.bytes); |
1143 | MD5Update(&md5c, pktin.body, 8); |
374330e2 |
1144 | MD5Final(session_id, &md5c); |
1145 | |
1146 | for (i=0; i<32; i++) |
1147 | session_key[i] = random_byte(); |
1148 | |
1149 | len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes); |
1150 | |
1151 | rsabuf = malloc(len); |
1152 | if (!rsabuf) |
1153 | fatalbox("Out of memory"); |
1154 | |
89ee5268 |
1155 | /* |
1156 | * Verify the host key. |
1157 | */ |
1158 | { |
1159 | /* |
1160 | * First format the key into a string. |
1161 | */ |
1162 | int len = rsastr_len(&hostkey); |
d5859615 |
1163 | char fingerprint[100]; |
89ee5268 |
1164 | char *keystr = malloc(len); |
1165 | if (!keystr) |
1166 | fatalbox("Out of memory"); |
1167 | rsastr_fmt(keystr, &hostkey); |
d5859615 |
1168 | rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey); |
d4857987 |
1169 | verify_ssh_host_key(savedhost, savedport, "rsa", keystr, fingerprint); |
89ee5268 |
1170 | free(keystr); |
1171 | } |
374330e2 |
1172 | |
1173 | for (i=0; i<32; i++) { |
1174 | rsabuf[i] = session_key[i]; |
1175 | if (i < 16) |
1176 | rsabuf[i] ^= session_id[i]; |
1177 | } |
1178 | |
1179 | if (hostkey.bytes > servkey.bytes) { |
1180 | rsaencrypt(rsabuf, 32, &servkey); |
1181 | rsaencrypt(rsabuf, servkey.bytes, &hostkey); |
1182 | } else { |
1183 | rsaencrypt(rsabuf, 32, &hostkey); |
1184 | rsaencrypt(rsabuf, hostkey.bytes, &servkey); |
1185 | } |
1186 | |
c5e9c988 |
1187 | logevent("Encrypted session key"); |
1188 | |
bea1ef5f |
1189 | cipher_type = cfg.cipher == CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH : |
9697bfd2 |
1190 | cfg.cipher == CIPHER_DES ? SSH_CIPHER_DES : |
bea1ef5f |
1191 | SSH_CIPHER_3DES; |
1192 | if ((supported_ciphers_mask & (1 << cipher_type)) == 0) { |
1193 | c_write("Selected cipher not supported, falling back to 3DES\r\n", 53); |
1194 | cipher_type = SSH_CIPHER_3DES; |
1195 | } |
c5e9c988 |
1196 | switch (cipher_type) { |
1197 | case SSH_CIPHER_3DES: logevent("Using 3DES encryption"); break; |
1198 | case SSH_CIPHER_DES: logevent("Using single-DES encryption"); break; |
1199 | case SSH_CIPHER_BLOWFISH: logevent("Using Blowfish encryption"); break; |
1200 | } |
bea1ef5f |
1201 | |
e5574168 |
1202 | send_packet(SSH1_CMSG_SESSION_KEY, |
fb09bf1c |
1203 | PKT_CHAR, cipher_type, |
1204 | PKT_DATA, cookie, 8, |
1205 | PKT_CHAR, (len*8) >> 8, PKT_CHAR, (len*8) & 0xFF, |
1206 | PKT_DATA, rsabuf, len, |
1207 | PKT_INT, 0, |
1208 | PKT_END); |
1209 | |
c5e9c988 |
1210 | logevent("Trying to enable encryption..."); |
374330e2 |
1211 | |
1212 | free(rsabuf); |
1213 | |
5e8358ad |
1214 | cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 : |
9697bfd2 |
1215 | cipher_type == SSH_CIPHER_DES ? &ssh_des : |
bea1ef5f |
1216 | &ssh_3des; |
374330e2 |
1217 | cipher->sesskey(session_key); |
1218 | |
fb09bf1c |
1219 | crWaitUntil(ispkt); |
374330e2 |
1220 | |
8d5de777 |
1221 | if (pktin.type != SSH1_SMSG_SUCCESS) { |
1222 | bombout(("Encryption not successfully enabled")); |
1223 | crReturn(0); |
1224 | } |
374330e2 |
1225 | |
c5e9c988 |
1226 | logevent("Successfully started encryption"); |
1227 | |
374330e2 |
1228 | fflush(stdout); |
1229 | { |
374330e2 |
1230 | static int pos = 0; |
1231 | static char c; |
67779be7 |
1232 | if ((flags & FLAG_INTERACTIVE) && !*cfg.username) { |
374330e2 |
1233 | c_write("login as: ", 10); |
67779be7 |
1234 | ssh_send_ok = 1; |
374330e2 |
1235 | while (pos >= 0) { |
fb09bf1c |
1236 | crWaitUntil(!ispkt); |
374330e2 |
1237 | while (inlen--) switch (c = *in++) { |
1238 | case 10: case 13: |
1239 | username[pos] = 0; |
1240 | pos = -1; |
1241 | break; |
1242 | case 8: case 127: |
1243 | if (pos > 0) { |
1244 | c_write("\b \b", 3); |
1245 | pos--; |
1246 | } |
1247 | break; |
1248 | case 21: case 27: |
1249 | while (pos > 0) { |
1250 | c_write("\b \b", 3); |
1251 | pos--; |
1252 | } |
1253 | break; |
1254 | case 3: case 4: |
1255 | random_save_seed(); |
1256 | exit(0); |
1257 | break; |
1258 | default: |
40d24aa6 |
1259 | if (((c >= ' ' && c <= '~') || |
1260 | ((unsigned char)c >= 160)) && pos < 40) { |
374330e2 |
1261 | username[pos++] = c; |
1262 | c_write(&c, 1); |
1263 | } |
1264 | break; |
1265 | } |
1266 | } |
1267 | c_write("\r\n", 2); |
1268 | username[strcspn(username, "\n\r")] = '\0'; |
1269 | } else { |
1270 | char stuff[200]; |
1271 | strncpy(username, cfg.username, 99); |
1272 | username[99] = '\0'; |
67779be7 |
1273 | if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) { |
fb09bf1c |
1274 | sprintf(stuff, "Sent username \"%s\".\r\n", username); |
4017be6d |
1275 | c_write(stuff, strlen(stuff)); |
fb09bf1c |
1276 | } |
374330e2 |
1277 | } |
fb09bf1c |
1278 | |
e5574168 |
1279 | send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END); |
c5e9c988 |
1280 | { |
1281 | char userlog[20+sizeof(username)]; |
1282 | sprintf(userlog, "Sent username \"%s\"", username); |
1283 | logevent(userlog); |
1284 | } |
374330e2 |
1285 | } |
1286 | |
fb09bf1c |
1287 | crWaitUntil(ispkt); |
374330e2 |
1288 | |
7cca0d81 |
1289 | tried_publickey = 0; |
1290 | |
e5574168 |
1291 | while (pktin.type == SSH1_SMSG_FAILURE) { |
374330e2 |
1292 | static char password[100]; |
a52f067e |
1293 | static char prompt[200]; |
374330e2 |
1294 | static int pos; |
1295 | static char c; |
ccbfb941 |
1296 | static int pwpkt_type; |
ccbfb941 |
1297 | /* |
1298 | * Show password prompt, having first obtained it via a TIS |
18515c51 |
1299 | * or CryptoCard exchange if we're doing TIS or CryptoCard |
1300 | * authentication. |
ccbfb941 |
1301 | */ |
e5574168 |
1302 | pwpkt_type = SSH1_CMSG_AUTH_PASSWORD; |
5c58ad2d |
1303 | if (agent_exists()) { |
1304 | /* |
1305 | * Attempt RSA authentication using Pageant. |
1306 | */ |
1307 | static unsigned char request[5], *response, *p; |
1308 | static int responselen; |
1309 | static int i, nkeys; |
1310 | static int authed = FALSE; |
1311 | void *r; |
1312 | |
1313 | logevent("Pageant is running. Requesting keys."); |
1314 | |
1315 | /* Request the keys held by the agent. */ |
1316 | PUT_32BIT(request, 1); |
1317 | request[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES; |
1318 | agent_query(request, 5, &r, &responselen); |
1319 | response = (unsigned char *)r; |
1320 | if (response) { |
1321 | p = response + 5; |
1322 | nkeys = GET_32BIT(p); p += 4; |
1323 | { char buf[64]; sprintf(buf, "Pageant has %d keys", nkeys); |
1324 | logevent(buf); } |
1325 | for (i = 0; i < nkeys; i++) { |
1326 | static struct RSAKey key; |
1327 | static Bignum challenge; |
b8bb811a |
1328 | static char *commentp; |
1329 | static int commentlen; |
5c58ad2d |
1330 | |
1331 | { char buf[64]; sprintf(buf, "Trying Pageant key #%d", i); |
1332 | logevent(buf); } |
1333 | p += 4; |
1334 | p += ssh1_read_bignum(p, &key.exponent); |
1335 | p += ssh1_read_bignum(p, &key.modulus); |
b8bb811a |
1336 | commentlen = GET_32BIT(p); p += 4; |
1337 | commentp = p; p += commentlen; |
5c58ad2d |
1338 | send_packet(SSH1_CMSG_AUTH_RSA, |
1339 | PKT_BIGNUM, key.modulus, PKT_END); |
1340 | crWaitUntil(ispkt); |
1341 | if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) { |
1342 | logevent("Key refused"); |
1343 | continue; |
1344 | } |
1345 | logevent("Received RSA challenge"); |
1346 | ssh1_read_bignum(pktin.body, &challenge); |
1347 | { |
1348 | char *agentreq, *q, *ret; |
1349 | int len, retlen; |
1350 | len = 1 + 4; /* message type, bit count */ |
1351 | len += ssh1_bignum_length(key.exponent); |
1352 | len += ssh1_bignum_length(key.modulus); |
1353 | len += ssh1_bignum_length(challenge); |
1354 | len += 16; /* session id */ |
1355 | len += 4; /* response format */ |
1356 | agentreq = malloc(4 + len); |
1357 | PUT_32BIT(agentreq, len); |
1358 | q = agentreq + 4; |
1359 | *q++ = SSH_AGENTC_RSA_CHALLENGE; |
1360 | PUT_32BIT(q, ssh1_bignum_bitcount(key.modulus)); |
1361 | q += 4; |
1362 | q += ssh1_write_bignum(q, key.exponent); |
1363 | q += ssh1_write_bignum(q, key.modulus); |
1364 | q += ssh1_write_bignum(q, challenge); |
1365 | memcpy(q, session_id, 16); q += 16; |
1366 | PUT_32BIT(q, 1); /* response format */ |
1367 | agent_query(agentreq, len+4, &ret, &retlen); |
1368 | free(agentreq); |
1369 | if (ret) { |
1370 | if (ret[4] == SSH_AGENT_RSA_RESPONSE) { |
1371 | logevent("Sending Pageant's response"); |
1372 | send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE, |
1373 | PKT_DATA, ret+5, 16, PKT_END); |
1374 | free(ret); |
1375 | crWaitUntil(ispkt); |
1376 | if (pktin.type == SSH1_SMSG_SUCCESS) { |
1377 | logevent("Pageant's response accepted"); |
c4fa2fce |
1378 | if (flags & FLAG_VERBOSE) { |
1379 | c_write("Authenticated using RSA key \"", |
1380 | 29); |
1381 | c_write(commentp, commentlen); |
1382 | c_write("\" from agent\r\n", 14); |
1383 | } |
5c58ad2d |
1384 | authed = TRUE; |
1385 | } else |
1386 | logevent("Pageant's response not accepted"); |
1387 | } else { |
1388 | logevent("Pageant failed to answer challenge"); |
1389 | free(ret); |
1390 | } |
1391 | } else { |
1392 | logevent("No reply received from Pageant"); |
1393 | } |
1394 | } |
1395 | freebn(key.exponent); |
1396 | freebn(key.modulus); |
1397 | freebn(challenge); |
1398 | if (authed) |
1399 | break; |
1400 | } |
1401 | } |
1402 | if (authed) |
1403 | break; |
1404 | } |
7cca0d81 |
1405 | if (*cfg.keyfile && !tried_publickey) |
1406 | pwpkt_type = SSH1_CMSG_AUTH_RSA; |
fb09bf1c |
1407 | |
a52f067e |
1408 | if (pktin.type == SSH1_SMSG_FAILURE && |
1409 | cfg.try_tis_auth && |
1410 | (supported_auths_mask & (1<<SSH1_AUTH_TIS))) { |
1411 | pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE; |
1412 | logevent("Requested TIS authentication"); |
1413 | send_packet(SSH1_CMSG_AUTH_TIS, PKT_END); |
1414 | crWaitUntil(ispkt); |
1415 | if (pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) { |
1416 | logevent("TIS authentication declined"); |
1417 | if (flags & FLAG_INTERACTIVE) |
1418 | c_write("TIS authentication refused.\r\n", 29); |
1419 | } else { |
1420 | int challengelen = ((pktin.body[0] << 24) | |
1421 | (pktin.body[1] << 16) | |
1422 | (pktin.body[2] << 8) | |
1423 | (pktin.body[3])); |
1424 | logevent("Received TIS challenge"); |
1425 | if (challengelen > sizeof(prompt)-1) |
1426 | challengelen = sizeof(prompt)-1; /* prevent overrun */ |
1427 | memcpy(prompt, pktin.body+4, challengelen); |
1428 | prompt[challengelen] = '\0'; |
1429 | } |
1430 | } |
1431 | if (pktin.type == SSH1_SMSG_FAILURE && |
1432 | cfg.try_tis_auth && |
1433 | (supported_auths_mask & (1<<SSH1_AUTH_CCARD))) { |
1434 | pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE; |
1435 | logevent("Requested CryptoCard authentication"); |
1436 | send_packet(SSH1_CMSG_AUTH_CCARD, PKT_END); |
1437 | crWaitUntil(ispkt); |
1438 | if (pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) { |
1439 | logevent("CryptoCard authentication declined"); |
1440 | c_write("CryptoCard authentication refused.\r\n", 29); |
1441 | } else { |
1442 | int challengelen = ((pktin.body[0] << 24) | |
1443 | (pktin.body[1] << 16) | |
1444 | (pktin.body[2] << 8) | |
1445 | (pktin.body[3])); |
1446 | logevent("Received CryptoCard challenge"); |
1447 | if (challengelen > sizeof(prompt)-1) |
1448 | challengelen = sizeof(prompt)-1; /* prevent overrun */ |
1449 | memcpy(prompt, pktin.body+4, challengelen); |
1450 | strncpy(prompt + challengelen, "\r\nResponse : ", |
1451 | sizeof(prompt)-challengelen); |
1452 | prompt[sizeof(prompt)-1] = '\0'; |
1453 | } |
1454 | } |
1455 | if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) { |
1456 | sprintf(prompt, "%.90s@%.90s's password: ", |
b585ec46 |
1457 | username, savedhost); |
a52f067e |
1458 | } |
1459 | if (pwpkt_type == SSH1_CMSG_AUTH_RSA) { |
1460 | char *comment = NULL; |
1461 | if (flags & FLAG_VERBOSE) |
1462 | c_write("Trying public key authentication.\r\n", 35); |
1463 | if (!rsakey_encrypted(cfg.keyfile, &comment)) { |
1464 | if (flags & FLAG_VERBOSE) |
1465 | c_write("No passphrase required.\r\n", 25); |
1466 | goto tryauth; |
1467 | } |
1468 | sprintf(prompt, "Passphrase for key \"%.100s\": ", comment); |
1469 | free(comment); |
1470 | } |
1471 | |
d8426c54 |
1472 | if (ssh_get_password) { |
85ee8208 |
1473 | if (!ssh_get_password(prompt, password, sizeof(password))) { |
1474 | /* |
1475 | * get_password failed to get a password (for |
1476 | * example because one was supplied on the command |
1477 | * line which has already failed to work). |
1478 | * Terminate. |
1479 | */ |
1480 | logevent("No more passwords to try"); |
1481 | ssh_state = SSH_STATE_CLOSED; |
1482 | crReturn(1); |
1483 | } |
fb09bf1c |
1484 | } else { |
a52f067e |
1485 | c_write(prompt, strlen(prompt)); |
7cca0d81 |
1486 | pos = 0; |
67779be7 |
1487 | ssh_send_ok = 1; |
7cca0d81 |
1488 | while (pos >= 0) { |
1489 | crWaitUntil(!ispkt); |
1490 | while (inlen--) switch (c = *in++) { |
1491 | case 10: case 13: |
1492 | password[pos] = 0; |
1493 | pos = -1; |
1494 | break; |
1495 | case 8: case 127: |
1496 | if (pos > 0) |
1497 | pos--; |
1498 | break; |
1499 | case 21: case 27: |
1500 | pos = 0; |
1501 | break; |
1502 | case 3: case 4: |
1503 | random_save_seed(); |
1504 | exit(0); |
1505 | break; |
1506 | default: |
1507 | if (((c >= ' ' && c <= '~') || |
1508 | ((unsigned char)c >= 160)) && pos < sizeof(password)) |
1509 | password[pos++] = c; |
1510 | break; |
1511 | } |
1512 | } |
1513 | c_write("\r\n", 2); |
a52f067e |
1514 | } |
fb09bf1c |
1515 | |
7cca0d81 |
1516 | tryauth: |
1517 | if (pwpkt_type == SSH1_CMSG_AUTH_RSA) { |
1518 | /* |
1519 | * Try public key authentication with the specified |
1520 | * key file. |
1521 | */ |
1522 | static struct RSAKey pubkey; |
1523 | static Bignum challenge, response; |
1524 | static int i; |
1525 | static unsigned char buffer[32]; |
1526 | |
1527 | tried_publickey = 1; |
6e522441 |
1528 | i = loadrsakey(cfg.keyfile, &pubkey, NULL, password); |
7cca0d81 |
1529 | if (i == 0) { |
1530 | c_write("Couldn't load public key from ", 30); |
1531 | c_write(cfg.keyfile, strlen(cfg.keyfile)); |
1532 | c_write(".\r\n", 3); |
1533 | continue; /* go and try password */ |
1534 | } |
1535 | if (i == -1) { |
1536 | c_write("Wrong passphrase.\r\n", 19); |
1537 | tried_publickey = 0; |
1538 | continue; /* try again */ |
1539 | } |
1540 | |
1541 | /* |
1542 | * Send a public key attempt. |
1543 | */ |
1544 | send_packet(SSH1_CMSG_AUTH_RSA, |
1545 | PKT_BIGNUM, pubkey.modulus, PKT_END); |
1546 | |
1547 | crWaitUntil(ispkt); |
1548 | if (pktin.type == SSH1_SMSG_FAILURE) { |
a52f067e |
1549 | c_write("Server refused our public key.\r\n", 32); |
7cca0d81 |
1550 | continue; /* go and try password */ |
1551 | } |
8d5de777 |
1552 | if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) { |
1553 | bombout(("Bizarre response to offer of public key")); |
1554 | crReturn(0); |
1555 | } |
7cca0d81 |
1556 | ssh1_read_bignum(pktin.body, &challenge); |
1557 | response = rsadecrypt(challenge, &pubkey); |
1558 | freebn(pubkey.private_exponent); /* burn the evidence */ |
1559 | |
1560 | for (i = 0; i < 32; i += 2) { |
1561 | buffer[i] = response[16-i/2] >> 8; |
1562 | buffer[i+1] = response[16-i/2] & 0xFF; |
1563 | } |
1564 | |
1565 | MD5Init(&md5c); |
1566 | MD5Update(&md5c, buffer, 32); |
1567 | MD5Update(&md5c, session_id, 16); |
1568 | MD5Final(buffer, &md5c); |
1569 | |
1570 | send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE, |
1571 | PKT_DATA, buffer, 16, PKT_END); |
1572 | |
1573 | crWaitUntil(ispkt); |
1574 | if (pktin.type == SSH1_SMSG_FAILURE) { |
4017be6d |
1575 | if (flags & FLAG_VERBOSE) |
1576 | c_write("Failed to authenticate with our public key.\r\n", |
1577 | 45); |
7cca0d81 |
1578 | continue; /* go and try password */ |
1579 | } else if (pktin.type != SSH1_SMSG_SUCCESS) { |
8d5de777 |
1580 | bombout(("Bizarre response to RSA authentication response")); |
1581 | crReturn(0); |
7cca0d81 |
1582 | } |
1583 | |
1584 | break; /* we're through! */ |
1585 | } else { |
1586 | send_packet(pwpkt_type, PKT_STR, password, PKT_END); |
1587 | } |
c5e9c988 |
1588 | logevent("Sent password"); |
374330e2 |
1589 | memset(password, 0, strlen(password)); |
fb09bf1c |
1590 | crWaitUntil(ispkt); |
e5574168 |
1591 | if (pktin.type == SSH1_SMSG_FAILURE) { |
4017be6d |
1592 | if (flags & FLAG_VERBOSE) |
1593 | c_write("Access denied\r\n", 15); |
c5e9c988 |
1594 | logevent("Authentication refused"); |
e5574168 |
1595 | } else if (pktin.type == SSH1_MSG_DISCONNECT) { |
fb09bf1c |
1596 | logevent("Received disconnect request"); |
85ee8208 |
1597 | ssh_state = SSH_STATE_CLOSED; |
1598 | crReturn(1); |
e5574168 |
1599 | } else if (pktin.type != SSH1_SMSG_SUCCESS) { |
8d5de777 |
1600 | bombout(("Strange packet received, type %d", pktin.type)); |
1601 | crReturn(0); |
374330e2 |
1602 | } |
1603 | } |
1604 | |
c5e9c988 |
1605 | logevent("Authentication successful"); |
1606 | |
fb09bf1c |
1607 | crFinish(1); |
1608 | } |
1609 | |
e5574168 |
1610 | static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) { |
fb09bf1c |
1611 | crBegin; |
1612 | |
1613 | random_init(); |
1614 | |
e5574168 |
1615 | while (!do_ssh1_login(in, inlen, ispkt)) { |
fb09bf1c |
1616 | crReturnV; |
85ee8208 |
1617 | } |
1618 | if (ssh_state == SSH_STATE_CLOSED) |
1619 | crReturnV; |
fb09bf1c |
1620 | |
979310f1 |
1621 | if (cfg.agentfwd && agent_exists()) { |
dacbd0e8 |
1622 | logevent("Requesting agent forwarding"); |
1623 | send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END); |
1624 | do { crReturnV; } while (!ispkt); |
1625 | if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) { |
8d5de777 |
1626 | bombout(("Protocol confusion")); |
1627 | crReturnV; |
dacbd0e8 |
1628 | } else if (pktin.type == SSH1_SMSG_FAILURE) { |
1629 | logevent("Agent forwarding refused"); |
1630 | } else |
1631 | logevent("Agent forwarding enabled"); |
1632 | } |
1633 | |
fef97f43 |
1634 | if (!cfg.nopty) { |
e5574168 |
1635 | send_packet(SSH1_CMSG_REQUEST_PTY, |
fb09bf1c |
1636 | PKT_STR, cfg.termtype, |
1637 | PKT_INT, rows, PKT_INT, cols, |
1638 | PKT_INT, 0, PKT_INT, 0, |
1639 | PKT_CHAR, 0, |
1640 | PKT_END); |
fef97f43 |
1641 | ssh_state = SSH_STATE_INTERMED; |
1642 | do { crReturnV; } while (!ispkt); |
e5574168 |
1643 | if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) { |
8d5de777 |
1644 | bombout(("Protocol confusion")); |
1645 | crReturnV; |
e5574168 |
1646 | } else if (pktin.type == SSH1_SMSG_FAILURE) { |
fef97f43 |
1647 | c_write("Server refused to allocate pty\r\n", 32); |
1648 | } |
c5e9c988 |
1649 | logevent("Allocated pty"); |
374330e2 |
1650 | } |
1651 | |
6abbf9e3 |
1652 | if (*cfg.remote_cmd) |
1653 | send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cfg.remote_cmd, PKT_END); |
1654 | else |
1655 | send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END); |
c5e9c988 |
1656 | logevent("Started session"); |
374330e2 |
1657 | |
1658 | ssh_state = SSH_STATE_SESSION; |
1659 | if (size_needed) |
1660 | ssh_size(); |
1661 | |
8ccc75b0 |
1662 | ssh_send_ok = 1; |
dacbd0e8 |
1663 | ssh_channels = newtree234(ssh_channelcmp); |
6f34e365 |
1664 | begin_session(); |
374330e2 |
1665 | while (1) { |
1666 | crReturnV; |
1667 | if (ispkt) { |
e5574168 |
1668 | if (pktin.type == SSH1_SMSG_STDOUT_DATA || |
1669 | pktin.type == SSH1_SMSG_STDERR_DATA) { |
fb09bf1c |
1670 | long len = GET_32BIT(pktin.body); |
fe50e814 |
1671 | from_backend(pktin.type == SSH1_SMSG_STDERR_DATA, |
1672 | pktin.body+4, len); |
e5574168 |
1673 | } else if (pktin.type == SSH1_MSG_DISCONNECT) { |
21248260 |
1674 | ssh_state = SSH_STATE_CLOSED; |
c5e9c988 |
1675 | logevent("Received disconnect request"); |
dacbd0e8 |
1676 | } else if (pktin.type == SSH1_SMSG_AGENT_OPEN) { |
1677 | /* Remote side is trying to open a channel to talk to our |
1678 | * agent. Give them back a local channel number. */ |
d211621f |
1679 | unsigned i = 1; |
dacbd0e8 |
1680 | struct ssh_channel *c; |
1681 | enum234 e; |
1682 | for (c = first234(ssh_channels, &e); c; c = next234(&e)) { |
1683 | if (c->localid > i) |
1684 | break; /* found a free number */ |
1685 | i = c->localid + 1; |
1686 | } |
1687 | c = malloc(sizeof(struct ssh_channel)); |
1688 | c->remoteid = GET_32BIT(pktin.body); |
1689 | c->localid = i; |
b8bb811a |
1690 | c->closes = 0; |
dacbd0e8 |
1691 | c->type = SSH1_SMSG_AGENT_OPEN; /* identify channel type */ |
bb487ce2 |
1692 | c->u.a.lensofar = 0; |
dacbd0e8 |
1693 | add234(ssh_channels, c); |
1694 | send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION, |
1695 | PKT_INT, c->remoteid, PKT_INT, c->localid, |
1696 | PKT_END); |
1697 | } else if (pktin.type == SSH1_MSG_CHANNEL_CLOSE || |
1698 | pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) { |
1699 | /* Remote side closes a channel. */ |
d211621f |
1700 | unsigned i = GET_32BIT(pktin.body); |
dacbd0e8 |
1701 | struct ssh_channel *c; |
1702 | c = find234(ssh_channels, &i, ssh_channelfind); |
1703 | if (c) { |
1704 | int closetype; |
1705 | closetype = (pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2); |
1706 | send_packet(pktin.type, PKT_INT, c->remoteid, PKT_END); |
1707 | c->closes |= closetype; |
1708 | if (c->closes == 3) { |
1709 | del234(ssh_channels, c); |
1710 | free(c); |
1711 | } |
1712 | } |
1713 | } else if (pktin.type == SSH1_MSG_CHANNEL_DATA) { |
1714 | /* Data sent down one of our channels. */ |
1715 | int i = GET_32BIT(pktin.body); |
1716 | int len = GET_32BIT(pktin.body+4); |
1717 | unsigned char *p = pktin.body+8; |
1718 | struct ssh_channel *c; |
1719 | c = find234(ssh_channels, &i, ssh_channelfind); |
1720 | if (c) { |
1721 | switch(c->type) { |
1722 | case SSH1_SMSG_AGENT_OPEN: |
1723 | /* Data for an agent message. Buffer it. */ |
1724 | while (len > 0) { |
1725 | if (c->u.a.lensofar < 4) { |
1726 | int l = min(4 - c->u.a.lensofar, len); |
1727 | memcpy(c->u.a.msglen + c->u.a.lensofar, p, l); |
1728 | p += l; len -= l; c->u.a.lensofar += l; |
1729 | } |
1730 | if (c->u.a.lensofar == 4) { |
1731 | c->u.a.totallen = 4 + GET_32BIT(c->u.a.msglen); |
1732 | c->u.a.message = malloc(c->u.a.totallen); |
1733 | memcpy(c->u.a.message, c->u.a.msglen, 4); |
1734 | } |
1735 | if (c->u.a.lensofar >= 4 && len > 0) { |
1736 | int l = min(c->u.a.totallen - c->u.a.lensofar, len); |
1737 | memcpy(c->u.a.message + c->u.a.lensofar, p, l); |
1738 | p += l; len -= l; c->u.a.lensofar += l; |
1739 | } |
1740 | if (c->u.a.lensofar == c->u.a.totallen) { |
1741 | void *reply, *sentreply; |
1742 | int replylen; |
1743 | agent_query(c->u.a.message, c->u.a.totallen, |
1744 | &reply, &replylen); |
1745 | if (reply) |
1746 | sentreply = reply; |
1747 | else { |
1748 | /* Fake SSH_AGENT_FAILURE. */ |
1749 | sentreply = "\0\0\0\1\5"; |
1750 | replylen = 5; |
1751 | } |
1752 | send_packet(SSH1_MSG_CHANNEL_DATA, |
1753 | PKT_INT, c->remoteid, |
1754 | PKT_INT, replylen, |
1755 | PKT_DATA, sentreply, replylen, |
1756 | PKT_END); |
1757 | if (reply) |
1758 | free(reply); |
1759 | free(c->u.a.message); |
1760 | c->u.a.lensofar = 0; |
1761 | } |
1762 | } |
1763 | break; |
1764 | } |
1765 | } |
e5574168 |
1766 | } else if (pktin.type == SSH1_SMSG_SUCCESS) { |
972a41c8 |
1767 | /* may be from EXEC_SHELL on some servers */ |
e5574168 |
1768 | } else if (pktin.type == SSH1_SMSG_FAILURE) { |
972a41c8 |
1769 | /* may be from EXEC_SHELL on some servers |
374330e2 |
1770 | * if no pty is available or in other odd cases. Ignore */ |
e5574168 |
1771 | } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) { |
1772 | send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END); |
374330e2 |
1773 | } else { |
8d5de777 |
1774 | bombout(("Strange packet received: type %d", pktin.type)); |
1775 | crReturnV; |
374330e2 |
1776 | } |
1777 | } else { |
e5574168 |
1778 | send_packet(SSH1_CMSG_STDIN_DATA, |
fb09bf1c |
1779 | PKT_INT, inlen, PKT_DATA, in, inlen, PKT_END); |
374330e2 |
1780 | } |
1781 | } |
1782 | |
1783 | crFinishV; |
1784 | } |
1785 | |
1786 | /* |
e5574168 |
1787 | * Utility routine for decoding comma-separated strings in KEXINIT. |
1788 | */ |
75cab814 |
1789 | static int in_commasep_string(char *needle, char *haystack, int haylen) { |
e5574168 |
1790 | int needlen = strlen(needle); |
1791 | while (1) { |
1792 | /* |
1793 | * Is it at the start of the string? |
1794 | */ |
1795 | if (haylen >= needlen && /* haystack is long enough */ |
1796 | !memcmp(needle, haystack, needlen) && /* initial match */ |
1797 | (haylen == needlen || haystack[needlen] == ',') |
1798 | /* either , or EOS follows */ |
1799 | ) |
1800 | return 1; |
1801 | /* |
1802 | * If not, search for the next comma and resume after that. |
1803 | * If no comma found, terminate. |
1804 | */ |
1805 | while (haylen > 0 && *haystack != ',') |
1806 | haylen--, haystack++; |
1807 | if (haylen == 0) |
1808 | return 0; |
1809 | haylen--, haystack++; /* skip over comma itself */ |
1810 | } |
1811 | } |
1812 | |
1813 | /* |
d39f364a |
1814 | * SSH2 key creation method. |
1815 | */ |
75cab814 |
1816 | static void ssh2_mkkey(Bignum K, char *H, char chr, char *keyspace) { |
d39f364a |
1817 | SHA_State s; |
1818 | /* First 20 bytes. */ |
1819 | SHA_Init(&s); |
1820 | sha_mpint(&s, K); |
1821 | SHA_Bytes(&s, H, 20); |
1822 | SHA_Bytes(&s, &chr, 1); |
1823 | SHA_Bytes(&s, H, 20); |
1824 | SHA_Final(&s, keyspace); |
1825 | /* Next 20 bytes. */ |
1826 | SHA_Init(&s); |
1827 | sha_mpint(&s, K); |
1828 | SHA_Bytes(&s, H, 20); |
1829 | SHA_Bytes(&s, keyspace, 20); |
1830 | SHA_Final(&s, keyspace+20); |
1831 | } |
1832 | |
1833 | /* |
7cca0d81 |
1834 | * Handle the SSH2 transport layer. |
e5574168 |
1835 | */ |
7cca0d81 |
1836 | static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt) |
e5574168 |
1837 | { |
1838 | static int i, len; |
1839 | static char *str; |
1840 | static Bignum e, f, K; |
7591b9ff |
1841 | static const struct ssh_mac **maclist; |
8b2715b2 |
1842 | static int nmacs; |
57476f6b |
1843 | static const struct ssh_cipher *cscipher_tobe = NULL; |
1844 | static const struct ssh_cipher *sccipher_tobe = NULL; |
1845 | static const struct ssh_mac *csmac_tobe = NULL; |
1846 | static const struct ssh_mac *scmac_tobe = NULL; |
1847 | static const struct ssh_compress *cscomp_tobe = NULL; |
1848 | static const struct ssh_compress *sccomp_tobe = NULL; |
d5859615 |
1849 | static char *hostkeydata, *sigdata, *keystr, *fingerprint; |
e5574168 |
1850 | static int hostkeylen, siglen; |
1851 | static unsigned char exchange_hash[20]; |
d39f364a |
1852 | static unsigned char keyspace[40]; |
57476f6b |
1853 | static const struct ssh_cipher *preferred_cipher; |
e5574168 |
1854 | |
1855 | crBegin; |
7cca0d81 |
1856 | random_init(); |
e5574168 |
1857 | |
5e8358ad |
1858 | /* |
1859 | * Set up the preferred cipher. |
1860 | */ |
1861 | if (cfg.cipher == CIPHER_BLOWFISH) { |
57476f6b |
1862 | preferred_cipher = &ssh_blowfish_ssh2; |
5e8358ad |
1863 | } else if (cfg.cipher == CIPHER_DES) { |
1864 | logevent("Single DES not supported in SSH2; using 3DES"); |
57476f6b |
1865 | preferred_cipher = &ssh_3des_ssh2; |
5e8358ad |
1866 | } else if (cfg.cipher == CIPHER_3DES) { |
57476f6b |
1867 | preferred_cipher = &ssh_3des_ssh2; |
5e8358ad |
1868 | } else { |
1869 | /* Shouldn't happen, but we do want to initialise to _something_. */ |
57476f6b |
1870 | preferred_cipher = &ssh_3des_ssh2; |
5e8358ad |
1871 | } |
1872 | |
7591b9ff |
1873 | /* |
1874 | * Be prepared to work around the buggy MAC problem. |
1875 | */ |
1876 | if (cfg.buggymac) |
8b2715b2 |
1877 | maclist = buggymacs, nmacs = lenof(buggymacs); |
7591b9ff |
1878 | else |
8b2715b2 |
1879 | maclist = macs, nmacs = lenof(macs); |
7591b9ff |
1880 | |
7cca0d81 |
1881 | begin_key_exchange: |
e5574168 |
1882 | /* |
1883 | * Construct and send our key exchange packet. |
1884 | */ |
1885 | ssh2_pkt_init(SSH2_MSG_KEXINIT); |
1886 | for (i = 0; i < 16; i++) |
1887 | ssh2_pkt_addbyte((unsigned char)random_byte()); |
1888 | /* List key exchange algorithms. */ |
1889 | ssh2_pkt_addstring_start(); |
1890 | for (i = 0; i < lenof(kex_algs); i++) { |
1891 | ssh2_pkt_addstring_str(kex_algs[i]->name); |
1892 | if (i < lenof(kex_algs)-1) |
1893 | ssh2_pkt_addstring_str(","); |
1894 | } |
1895 | /* List server host key algorithms. */ |
1896 | ssh2_pkt_addstring_start(); |
1897 | for (i = 0; i < lenof(hostkey_algs); i++) { |
1898 | ssh2_pkt_addstring_str(hostkey_algs[i]->name); |
1899 | if (i < lenof(hostkey_algs)-1) |
1900 | ssh2_pkt_addstring_str(","); |
1901 | } |
1902 | /* List client->server encryption algorithms. */ |
1903 | ssh2_pkt_addstring_start(); |
729e54b4 |
1904 | for (i = 0; i < lenof(ciphers)+1; i++) { |
1905 | const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1]; |
57476f6b |
1906 | ssh2_pkt_addstring_str(c->name); |
729e54b4 |
1907 | if (i < lenof(ciphers)) |
e5574168 |
1908 | ssh2_pkt_addstring_str(","); |
1909 | } |
1910 | /* List server->client encryption algorithms. */ |
1911 | ssh2_pkt_addstring_start(); |
729e54b4 |
1912 | for (i = 0; i < lenof(ciphers)+1; i++) { |
1913 | const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1]; |
57476f6b |
1914 | ssh2_pkt_addstring_str(c->name); |
729e54b4 |
1915 | if (i < lenof(ciphers)) |
e5574168 |
1916 | ssh2_pkt_addstring_str(","); |
1917 | } |
1918 | /* List client->server MAC algorithms. */ |
1919 | ssh2_pkt_addstring_start(); |
8b2715b2 |
1920 | for (i = 0; i < nmacs; i++) { |
7591b9ff |
1921 | ssh2_pkt_addstring_str(maclist[i]->name); |
8b2715b2 |
1922 | if (i < nmacs-1) |
e5574168 |
1923 | ssh2_pkt_addstring_str(","); |
1924 | } |
1925 | /* List server->client MAC algorithms. */ |
1926 | ssh2_pkt_addstring_start(); |
8b2715b2 |
1927 | for (i = 0; i < nmacs; i++) { |
7591b9ff |
1928 | ssh2_pkt_addstring_str(maclist[i]->name); |
8b2715b2 |
1929 | if (i < nmacs-1) |
e5574168 |
1930 | ssh2_pkt_addstring_str(","); |
1931 | } |
1932 | /* List client->server compression algorithms. */ |
1933 | ssh2_pkt_addstring_start(); |
1934 | for (i = 0; i < lenof(compressions); i++) { |
1935 | ssh2_pkt_addstring_str(compressions[i]->name); |
1936 | if (i < lenof(compressions)-1) |
1937 | ssh2_pkt_addstring_str(","); |
1938 | } |
1939 | /* List server->client compression algorithms. */ |
1940 | ssh2_pkt_addstring_start(); |
1941 | for (i = 0; i < lenof(compressions); i++) { |
1942 | ssh2_pkt_addstring_str(compressions[i]->name); |
1943 | if (i < lenof(compressions)-1) |
1944 | ssh2_pkt_addstring_str(","); |
1945 | } |
1946 | /* List client->server languages. Empty list. */ |
1947 | ssh2_pkt_addstring_start(); |
1948 | /* List server->client languages. Empty list. */ |
1949 | ssh2_pkt_addstring_start(); |
1950 | /* First KEX packet does _not_ follow, because we're not that brave. */ |
1951 | ssh2_pkt_addbool(FALSE); |
1952 | /* Reserved. */ |
1953 | ssh2_pkt_adduint32(0); |
1954 | sha_string(&exhash, pktout.data+5, pktout.length-5); |
1955 | ssh2_pkt_send(); |
1956 | |
1957 | if (!ispkt) crWaitUntil(ispkt); |
1958 | sha_string(&exhash, pktin.data+5, pktin.length-5); |
1959 | |
1960 | /* |
1961 | * Now examine the other side's KEXINIT to see what we're up |
1962 | * to. |
1963 | */ |
7cca0d81 |
1964 | if (pktin.type != SSH2_MSG_KEXINIT) { |
8d5de777 |
1965 | bombout(("expected key exchange packet from server")); |
1966 | crReturn(0); |
7cca0d81 |
1967 | } |
e5574168 |
1968 | kex = NULL; hostkey = NULL; cscipher_tobe = NULL; sccipher_tobe = NULL; |
1969 | csmac_tobe = NULL; scmac_tobe = NULL; cscomp_tobe = NULL; sccomp_tobe = NULL; |
1970 | pktin.savedpos += 16; /* skip garbage cookie */ |
1971 | ssh2_pkt_getstring(&str, &len); /* key exchange algorithms */ |
1972 | for (i = 0; i < lenof(kex_algs); i++) { |
1973 | if (in_commasep_string(kex_algs[i]->name, str, len)) { |
1974 | kex = kex_algs[i]; |
1975 | break; |
1976 | } |
1977 | } |
1978 | ssh2_pkt_getstring(&str, &len); /* host key algorithms */ |
1979 | for (i = 0; i < lenof(hostkey_algs); i++) { |
1980 | if (in_commasep_string(hostkey_algs[i]->name, str, len)) { |
1981 | hostkey = hostkey_algs[i]; |
1982 | break; |
1983 | } |
1984 | } |
1985 | ssh2_pkt_getstring(&str, &len); /* client->server cipher */ |
729e54b4 |
1986 | for (i = 0; i < lenof(ciphers)+1; i++) { |
1987 | const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1]; |
57476f6b |
1988 | if (in_commasep_string(c->name, str, len)) { |
729e54b4 |
1989 | cscipher_tobe = c; |
e5574168 |
1990 | break; |
1991 | } |
1992 | } |
1993 | ssh2_pkt_getstring(&str, &len); /* server->client cipher */ |
729e54b4 |
1994 | for (i = 0; i < lenof(ciphers)+1; i++) { |
1995 | const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1]; |
57476f6b |
1996 | if (in_commasep_string(c->name, str, len)) { |
729e54b4 |
1997 | sccipher_tobe = c; |
e5574168 |
1998 | break; |
1999 | } |
2000 | } |
2001 | ssh2_pkt_getstring(&str, &len); /* client->server mac */ |
8b2715b2 |
2002 | for (i = 0; i < nmacs; i++) { |
7591b9ff |
2003 | if (in_commasep_string(maclist[i]->name, str, len)) { |
2004 | csmac_tobe = maclist[i]; |
e5574168 |
2005 | break; |
2006 | } |
2007 | } |
2008 | ssh2_pkt_getstring(&str, &len); /* server->client mac */ |
8b2715b2 |
2009 | for (i = 0; i < nmacs; i++) { |
7591b9ff |
2010 | if (in_commasep_string(maclist[i]->name, str, len)) { |
2011 | scmac_tobe = maclist[i]; |
e5574168 |
2012 | break; |
2013 | } |
2014 | } |
2015 | ssh2_pkt_getstring(&str, &len); /* client->server compression */ |
2016 | for (i = 0; i < lenof(compressions); i++) { |
2017 | if (in_commasep_string(compressions[i]->name, str, len)) { |
2018 | cscomp_tobe = compressions[i]; |
2019 | break; |
2020 | } |
2021 | } |
2022 | ssh2_pkt_getstring(&str, &len); /* server->client compression */ |
2023 | for (i = 0; i < lenof(compressions); i++) { |
2024 | if (in_commasep_string(compressions[i]->name, str, len)) { |
2025 | sccomp_tobe = compressions[i]; |
2026 | break; |
2027 | } |
2028 | } |
e5574168 |
2029 | |
2030 | /* |
2031 | * Currently we only support Diffie-Hellman and DSS, so let's |
2032 | * bomb out if those aren't selected. |
2033 | */ |
8d5de777 |
2034 | if (kex != &ssh_diffiehellman || hostkey != &ssh_dss) { |
2035 | bombout(("internal fault: chaos in SSH 2 transport layer")); |
2036 | crReturn(0); |
2037 | } |
e5574168 |
2038 | |
2039 | /* |
2040 | * Now we begin the fun. Generate and send e for Diffie-Hellman. |
2041 | */ |
2042 | e = dh_create_e(); |
e5574168 |
2043 | ssh2_pkt_init(SSH2_MSG_KEXDH_INIT); |
2044 | ssh2_pkt_addmp(e); |
2045 | ssh2_pkt_send(); |
2046 | |
2047 | crWaitUntil(ispkt); |
7cca0d81 |
2048 | if (pktin.type != SSH2_MSG_KEXDH_REPLY) { |
8d5de777 |
2049 | bombout(("expected key exchange packet from server")); |
2050 | crReturn(0); |
7cca0d81 |
2051 | } |
e5574168 |
2052 | ssh2_pkt_getstring(&hostkeydata, &hostkeylen); |
2053 | f = ssh2_pkt_getmp(); |
e5574168 |
2054 | ssh2_pkt_getstring(&sigdata, &siglen); |
2055 | |
2056 | K = dh_find_K(f); |
e5574168 |
2057 | |
2058 | sha_string(&exhash, hostkeydata, hostkeylen); |
2059 | sha_mpint(&exhash, e); |
2060 | sha_mpint(&exhash, f); |
2061 | sha_mpint(&exhash, K); |
2062 | SHA_Final(&exhash, exchange_hash); |
2063 | |
7cca0d81 |
2064 | #if 0 |
e5574168 |
2065 | debug(("Exchange hash is:\r\n")); |
2066 | for (i = 0; i < 20; i++) |
2067 | debug((" %02x", exchange_hash[i])); |
2068 | debug(("\r\n")); |
7cca0d81 |
2069 | #endif |
2070 | |
2071 | hostkey->setkey(hostkeydata, hostkeylen); |
8d5de777 |
2072 | if (!hostkey->verifysig(sigdata, siglen, exchange_hash, 20)) { |
2073 | bombout(("Server failed host key check")); |
2074 | crReturn(0); |
2075 | } |
e5574168 |
2076 | |
2077 | /* |
7cca0d81 |
2078 | * Expect SSH2_MSG_NEWKEYS from server. |
d39f364a |
2079 | */ |
7cca0d81 |
2080 | crWaitUntil(ispkt); |
8d5de777 |
2081 | if (pktin.type != SSH2_MSG_NEWKEYS) { |
2082 | bombout(("expected new-keys packet from server")); |
2083 | crReturn(0); |
2084 | } |
d39f364a |
2085 | |
2086 | /* |
7cca0d81 |
2087 | * Authenticate remote host: verify host key. (We've already |
2088 | * checked the signature of the exchange hash.) |
e5574168 |
2089 | */ |
7cca0d81 |
2090 | keystr = hostkey->fmtkey(); |
d5859615 |
2091 | fingerprint = hostkey->fingerprint(); |
d4857987 |
2092 | verify_ssh_host_key(savedhost, savedport, hostkey->keytype, |
2093 | keystr, fingerprint); |
d5859615 |
2094 | logevent("Host key fingerprint is:"); |
2095 | logevent(fingerprint); |
2096 | free(fingerprint); |
7cca0d81 |
2097 | free(keystr); |
d39f364a |
2098 | |
2099 | /* |
7cca0d81 |
2100 | * Send SSH2_MSG_NEWKEYS. |
d39f364a |
2101 | */ |
2102 | ssh2_pkt_init(SSH2_MSG_NEWKEYS); |
2103 | ssh2_pkt_send(); |
d39f364a |
2104 | |
2105 | /* |
2106 | * Create and initialise session keys. |
2107 | */ |
2108 | cscipher = cscipher_tobe; |
2109 | sccipher = sccipher_tobe; |
2110 | csmac = csmac_tobe; |
2111 | scmac = scmac_tobe; |
2112 | cscomp = cscomp_tobe; |
2113 | sccomp = sccomp_tobe; |
2114 | /* |
2115 | * Set IVs after keys. |
2116 | */ |
2117 | ssh2_mkkey(K, exchange_hash, 'C', keyspace); cscipher->setcskey(keyspace); |
2118 | ssh2_mkkey(K, exchange_hash, 'D', keyspace); cscipher->setsckey(keyspace); |
2119 | ssh2_mkkey(K, exchange_hash, 'A', keyspace); cscipher->setcsiv(keyspace); |
2120 | ssh2_mkkey(K, exchange_hash, 'B', keyspace); sccipher->setsciv(keyspace); |
2121 | ssh2_mkkey(K, exchange_hash, 'E', keyspace); csmac->setcskey(keyspace); |
2122 | ssh2_mkkey(K, exchange_hash, 'F', keyspace); scmac->setsckey(keyspace); |
2123 | |
033b4cef |
2124 | /* |
7cca0d81 |
2125 | * Now we're encrypting. Begin returning 1 to the protocol main |
2126 | * function so that other things can run on top of the |
2127 | * transport. If we ever see a KEXINIT, we must go back to the |
2128 | * start. |
033b4cef |
2129 | */ |
7cca0d81 |
2130 | do { |
2131 | crReturn(1); |
2132 | } while (!(ispkt && pktin.type == SSH2_MSG_KEXINIT)); |
2133 | goto begin_key_exchange; |
e5574168 |
2134 | |
2135 | crFinish(1); |
2136 | } |
2137 | |
7cca0d81 |
2138 | /* |
2139 | * Handle the SSH2 userauth and connection layers. |
2140 | */ |
2141 | static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) |
2142 | { |
7cca0d81 |
2143 | static unsigned long remote_winsize; |
2144 | static unsigned long remote_maxpkt; |
2145 | |
e5574168 |
2146 | crBegin; |
2147 | |
7cca0d81 |
2148 | /* |
2149 | * Request userauth protocol, and await a response to it. |
2150 | */ |
2151 | ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST); |
2152 | ssh2_pkt_addstring("ssh-userauth"); |
2153 | ssh2_pkt_send(); |
2154 | crWaitUntilV(ispkt); |
8d5de777 |
2155 | if (pktin.type != SSH2_MSG_SERVICE_ACCEPT) { |
2156 | bombout(("Server refused user authentication protocol")); |
2157 | crReturnV; |
2158 | } |
7cca0d81 |
2159 | |
2160 | /* |
2161 | * FIXME: currently we support only password authentication. |
2162 | * (This places us technically in violation of the SSH2 spec. |
2163 | * We must fix this.) |
2164 | */ |
2165 | while (1) { |
2166 | /* |
2167 | * Get a username and a password. |
2168 | */ |
2169 | static char username[100]; |
2170 | static char password[100]; |
2171 | static int pos = 0; |
2172 | static char c; |
e5574168 |
2173 | |
67779be7 |
2174 | if ((flags & FLAG_INTERACTIVE) && !*cfg.username) { |
7cca0d81 |
2175 | c_write("login as: ", 10); |
67779be7 |
2176 | ssh_send_ok = 1; |
7cca0d81 |
2177 | while (pos >= 0) { |
2178 | crWaitUntilV(!ispkt); |
2179 | while (inlen--) switch (c = *in++) { |
2180 | case 10: case 13: |
2181 | username[pos] = 0; |
2182 | pos = -1; |
2183 | break; |
2184 | case 8: case 127: |
2185 | if (pos > 0) { |
2186 | c_write("\b \b", 3); |
2187 | pos--; |
2188 | } |
2189 | break; |
2190 | case 21: case 27: |
2191 | while (pos > 0) { |
2192 | c_write("\b \b", 3); |
2193 | pos--; |
2194 | } |
2195 | break; |
2196 | case 3: case 4: |
2197 | random_save_seed(); |
2198 | exit(0); |
2199 | break; |
2200 | default: |
2201 | if (((c >= ' ' && c <= '~') || |
2202 | ((unsigned char)c >= 160)) && pos < 40) { |
2203 | username[pos++] = c; |
2204 | c_write(&c, 1); |
2205 | } |
2206 | break; |
2207 | } |
2208 | } |
2209 | c_write("\r\n", 2); |
2210 | username[strcspn(username, "\n\r")] = '\0'; |
2211 | } else { |
2212 | char stuff[200]; |
2213 | strncpy(username, cfg.username, 99); |
2214 | username[99] = '\0'; |
67779be7 |
2215 | if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) { |
7cca0d81 |
2216 | sprintf(stuff, "Using username \"%s\".\r\n", username); |
2217 | c_write(stuff, strlen(stuff)); |
2218 | } |
2219 | } |
2220 | |
d8426c54 |
2221 | if (ssh_get_password) { |
7cca0d81 |
2222 | char prompt[200]; |
b585ec46 |
2223 | sprintf(prompt, "%.90s@%.90s's password: ", username, savedhost); |
7cca0d81 |
2224 | if (!ssh_get_password(prompt, password, sizeof(password))) { |
2225 | /* |
2226 | * get_password failed to get a password (for |
2227 | * example because one was supplied on the command |
2228 | * line which has already failed to work). |
2229 | * Terminate. |
2230 | */ |
2231 | logevent("No more passwords to try"); |
2232 | ssh_state = SSH_STATE_CLOSED; |
2233 | crReturnV; |
2234 | } |
2235 | } else { |
2236 | c_write("password: ", 10); |
67779be7 |
2237 | ssh_send_ok = 1; |
7cca0d81 |
2238 | |
2239 | pos = 0; |
2240 | while (pos >= 0) { |
2241 | crWaitUntilV(!ispkt); |
2242 | while (inlen--) switch (c = *in++) { |
2243 | case 10: case 13: |
2244 | password[pos] = 0; |
2245 | pos = -1; |
2246 | break; |
2247 | case 8: case 127: |
2248 | if (pos > 0) |
2249 | pos--; |
2250 | break; |
2251 | case 21: case 27: |
2252 | pos = 0; |
2253 | break; |
2254 | case 3: case 4: |
2255 | random_save_seed(); |
2256 | exit(0); |
2257 | break; |
2258 | default: |
2259 | if (((c >= ' ' && c <= '~') || |
2260 | ((unsigned char)c >= 160)) && pos < 40) |
2261 | password[pos++] = c; |
2262 | break; |
2263 | } |
2264 | } |
2265 | c_write("\r\n", 2); |
2266 | } |
2267 | |
2268 | ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST); |
2269 | ssh2_pkt_addstring(username); |
2270 | ssh2_pkt_addstring("ssh-connection"); /* service requested */ |
2271 | ssh2_pkt_addstring("password"); |
2272 | ssh2_pkt_addbool(FALSE); |
2273 | ssh2_pkt_addstring(password); |
2274 | ssh2_pkt_send(); |
2275 | |
2276 | crWaitUntilV(ispkt); |
2277 | if (pktin.type != SSH2_MSG_USERAUTH_SUCCESS) { |
2278 | c_write("Access denied\r\n", 15); |
2279 | logevent("Authentication refused"); |
2280 | } else |
2281 | break; |
2282 | } |
2283 | |
2284 | /* |
2285 | * Now we're authenticated for the connection protocol. The |
2286 | * connection protocol will automatically have started at this |
2287 | * point; there's no need to send SERVICE_REQUEST. |
2288 | */ |
2289 | |
2290 | /* |
2291 | * So now create a channel with a session in it. |
2292 | */ |
d211621f |
2293 | mainchan = malloc(sizeof(struct ssh_channel)); |
2294 | mainchan->localid = 100; /* as good as any */ |
7cca0d81 |
2295 | ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN); |
2296 | ssh2_pkt_addstring("session"); |
d211621f |
2297 | ssh2_pkt_adduint32(mainchan->localid); |
cf6e59d6 |
2298 | ssh2_pkt_adduint32(0x8000UL); /* our window size */ |
d211621f |
2299 | ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */ |
7cca0d81 |
2300 | ssh2_pkt_send(); |
2301 | crWaitUntilV(ispkt); |
2302 | if (pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) { |
8d5de777 |
2303 | bombout(("Server refused to open a session")); |
2304 | crReturnV; |
7cca0d81 |
2305 | /* FIXME: error data comes back in FAILURE packet */ |
2306 | } |
d211621f |
2307 | if (ssh2_pkt_getuint32() != mainchan->localid) { |
8d5de777 |
2308 | bombout(("Server's channel confirmation cited wrong channel")); |
2309 | crReturnV; |
7cca0d81 |
2310 | } |
d211621f |
2311 | mainchan->remoteid = ssh2_pkt_getuint32(); |
2312 | mainchan->u.v2.remwindow = ssh2_pkt_getuint32(); |
2313 | mainchan->u.v2.remmaxpkt = ssh2_pkt_getuint32(); |
2314 | mainchan->u.v2.outbuffer = NULL; |
2315 | mainchan->u.v2.outbuflen = mainchan->u.v2.outbufsize = 0; |
7cca0d81 |
2316 | logevent("Opened channel for session"); |
2317 | |
2318 | /* |
2319 | * Now allocate a pty for the session. |
2320 | */ |
67779be7 |
2321 | if (!cfg.nopty) { |
2322 | ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST); |
2323 | ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */ |
2324 | ssh2_pkt_addstring("pty-req"); |
2325 | ssh2_pkt_addbool(1); /* want reply */ |
2326 | ssh2_pkt_addstring(cfg.termtype); |
2327 | ssh2_pkt_adduint32(cols); |
2328 | ssh2_pkt_adduint32(rows); |
2329 | ssh2_pkt_adduint32(0); /* pixel width */ |
2330 | ssh2_pkt_adduint32(0); /* pixel height */ |
2331 | ssh2_pkt_addstring_start(); |
2332 | ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */ |
2333 | ssh2_pkt_send(); |
7cca0d81 |
2334 | |
67779be7 |
2335 | do { |
2336 | crWaitUntilV(ispkt); |
2337 | if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) { |
2338 | /* FIXME: be able to handle other channels here */ |
2339 | if (ssh2_pkt_getuint32() != mainchan->localid) |
2340 | continue; /* wrong channel */ |
2341 | mainchan->u.v2.remwindow += ssh2_pkt_getuint32(); |
2342 | } |
2343 | } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST); |
7cca0d81 |
2344 | |
67779be7 |
2345 | if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) { |
2346 | if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) { |
8d5de777 |
2347 | bombout(("Server got confused by pty request")); |
2348 | crReturnV; |
67779be7 |
2349 | } |
2350 | c_write("Server refused to allocate pty\r\n", 32); |
2351 | } else { |
2352 | logevent("Allocated pty"); |
7cca0d81 |
2353 | } |
7cca0d81 |
2354 | } |
2355 | |
2356 | /* |
67779be7 |
2357 | * Start a shell or a remote command. |
7cca0d81 |
2358 | */ |
2359 | ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST); |
d211621f |
2360 | ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */ |
67779be7 |
2361 | if (*cfg.remote_cmd) { |
2362 | ssh2_pkt_addstring("exec"); |
2363 | ssh2_pkt_addbool(1); /* want reply */ |
2364 | ssh2_pkt_addstring(cfg.remote_cmd); |
2365 | } else { |
2366 | ssh2_pkt_addstring("shell"); |
2367 | ssh2_pkt_addbool(1); /* want reply */ |
2368 | } |
7cca0d81 |
2369 | ssh2_pkt_send(); |
d211621f |
2370 | do { |
7cca0d81 |
2371 | crWaitUntilV(ispkt); |
d211621f |
2372 | if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) { |
2373 | /* FIXME: be able to handle other channels here */ |
2374 | if (ssh2_pkt_getuint32() != mainchan->localid) |
2375 | continue; /* wrong channel */ |
2376 | mainchan->u.v2.remwindow += ssh2_pkt_getuint32(); |
2377 | } |
7cca0d81 |
2378 | } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST); |
2379 | if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) { |
2380 | if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) { |
8d5de777 |
2381 | bombout(("Server got confused by shell/command request")); |
2382 | crReturnV; |
7cca0d81 |
2383 | } |
8d5de777 |
2384 | bombout(("Server refused to start a shell/command")); |
2385 | crReturnV; |
7cca0d81 |
2386 | } else { |
8d5de777 |
2387 | logevent("Started a shell/command"); |
7cca0d81 |
2388 | } |
2389 | |
2390 | /* |
2391 | * Transfer data! |
2392 | */ |
8ccc75b0 |
2393 | ssh_send_ok = 1; |
6f34e365 |
2394 | begin_session(); |
7cca0d81 |
2395 | while (1) { |
d211621f |
2396 | static int try_send; |
e5574168 |
2397 | crReturnV; |
d211621f |
2398 | try_send = FALSE; |
7cca0d81 |
2399 | if (ispkt) { |
2400 | if (pktin.type == SSH2_MSG_CHANNEL_DATA || |
2401 | pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) { |
2402 | char *data; |
2403 | int length; |
d211621f |
2404 | /* FIXME: be able to handle other channels here */ |
2405 | if (ssh2_pkt_getuint32() != mainchan->localid) |
7cca0d81 |
2406 | continue; /* wrong channel */ |
2407 | if (pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA && |
2408 | ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR) |
2409 | continue; /* extended but not stderr */ |
2410 | ssh2_pkt_getstring(&data, &length); |
d211621f |
2411 | if (data) { |
fe50e814 |
2412 | from_backend(pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA, |
2413 | data, length); |
d211621f |
2414 | /* |
2415 | * Enlarge the window again at the remote side, |
2416 | * just in case it ever runs down and they fail |
2417 | * to send us any more data. |
2418 | */ |
2419 | ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST); |
2420 | ssh2_pkt_adduint32(mainchan->remoteid); |
2421 | ssh2_pkt_adduint32(length); |
2422 | ssh2_pkt_send(); |
2423 | } |
7cca0d81 |
2424 | } else if (pktin.type == SSH2_MSG_DISCONNECT) { |
2425 | ssh_state = SSH_STATE_CLOSED; |
d211621f |
2426 | logevent("Received disconnect message"); |
7cca0d81 |
2427 | } else if (pktin.type == SSH2_MSG_CHANNEL_REQUEST) { |
2428 | continue; /* exit status et al; ignore (FIXME?) */ |
d211621f |
2429 | } else if (pktin.type == SSH2_MSG_CHANNEL_EOF) { |
2430 | continue; /* remote sends EOF; ignore */ |
2431 | } else if (pktin.type == SSH2_MSG_CHANNEL_CLOSE) { |
2432 | /* FIXME: be able to handle other channels here */ |
2433 | if (ssh2_pkt_getuint32() != mainchan->localid) |
2434 | continue; /* wrong channel */ |
2435 | ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE); |
2436 | ssh2_pkt_adduint32(mainchan->remoteid); |
2437 | ssh2_pkt_send(); |
2438 | /* FIXME: mark the channel as closed */ |
2439 | if (1 /* FIXME: "all channels are closed" */) { |
2440 | logevent("All channels closed. Disconnecting"); |
2441 | ssh2_pkt_init(SSH2_MSG_DISCONNECT); |
2442 | ssh2_pkt_send(); |
cf6e59d6 |
2443 | ssh_state = SSH_STATE_CLOSED; |
2444 | closesocket(s); |
2445 | s = INVALID_SOCKET; |
d211621f |
2446 | } |
2447 | continue; /* remote sends close; ignore (FIXME) */ |
7cca0d81 |
2448 | } else if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) { |
d211621f |
2449 | /* FIXME: be able to handle other channels here */ |
2450 | if (ssh2_pkt_getuint32() != mainchan->localid) |
2451 | continue; /* wrong channel */ |
2452 | mainchan->u.v2.remwindow += ssh2_pkt_getuint32(); |
2453 | try_send = TRUE; |
7cca0d81 |
2454 | } else { |
8d5de777 |
2455 | bombout(("Strange packet received: type %d", pktin.type)); |
2456 | crReturnV; |
7cca0d81 |
2457 | } |
2458 | } else { |
d211621f |
2459 | /* |
2460 | * We have spare data. Add it to the channel buffer. |
2461 | */ |
2462 | if (mainchan->u.v2.outbufsize < |
2463 | mainchan->u.v2.outbuflen + inlen) { |
2464 | mainchan->u.v2.outbufsize = |
2465 | mainchan->u.v2.outbuflen + inlen + 1024; |
2466 | mainchan->u.v2.outbuffer = srealloc(mainchan->u.v2.outbuffer, |
2467 | mainchan->u.v2.outbufsize); |
2468 | } |
2469 | memcpy(mainchan->u.v2.outbuffer + mainchan->u.v2.outbuflen, |
2470 | in, inlen); |
2471 | mainchan->u.v2.outbuflen += inlen; |
2472 | try_send = TRUE; |
7cca0d81 |
2473 | } |
d211621f |
2474 | if (try_send) { |
2475 | /* |
2476 | * Try to send data on the channel if we can. (FIXME: |
2477 | * on _all_ channels.) |
2478 | */ |
2479 | while (mainchan->u.v2.remwindow > 0 && |
2480 | mainchan->u.v2.outbuflen > 0) { |
2481 | unsigned len = mainchan->u.v2.remwindow; |
2482 | if (len > mainchan->u.v2.outbuflen) |
2483 | len = mainchan->u.v2.outbuflen; |
2484 | if (len > mainchan->u.v2.remmaxpkt) |
2485 | len = mainchan->u.v2.remmaxpkt; |
2486 | ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA); |
2487 | ssh2_pkt_adduint32(mainchan->remoteid); |
2488 | ssh2_pkt_addstring_start(); |
2489 | ssh2_pkt_addstring_data(mainchan->u.v2.outbuffer, len); |
2490 | ssh2_pkt_send(); |
2491 | mainchan->u.v2.outbuflen -= len; |
2492 | memmove(mainchan->u.v2.outbuffer, mainchan->u.v2.outbuffer+len, |
2493 | mainchan->u.v2.outbuflen); |
2494 | mainchan->u.v2.remwindow -= len; |
2495 | } |
2496 | } |
e5574168 |
2497 | } |
2498 | |
2499 | crFinishV; |
2500 | } |
2501 | |
2502 | /* |
7cca0d81 |
2503 | * Handle the top-level SSH2 protocol. |
2504 | */ |
2505 | static void ssh2_protocol(unsigned char *in, int inlen, int ispkt) |
2506 | { |
2507 | if (do_ssh2_transport(in, inlen, ispkt) == 0) |
2508 | return; |
2509 | do_ssh2_authconn(in, inlen, ispkt); |
2510 | } |
2511 | |
2512 | /* |
374330e2 |
2513 | * Called to set up the connection. Will arrange for WM_NETEVENT |
2514 | * messages to be passed to the specified window, whose window |
2515 | * procedure should then call telnet_msg(). |
2516 | * |
2517 | * Returns an error message, or NULL on success. |
374330e2 |
2518 | */ |
2519 | static char *ssh_init (HWND hwnd, char *host, int port, char **realhost) { |
fb09bf1c |
2520 | char *p; |
8f203108 |
2521 | |
2522 | #ifdef MSCRYPTOAPI |
2523 | if(crypto_startup() == 0) |
2524 | return "Microsoft high encryption pack not installed!"; |
2525 | #endif |
374330e2 |
2526 | |
fb09bf1c |
2527 | p = connect_to_host(host, port, realhost); |
2528 | if (p != NULL) |
2529 | return p; |
374330e2 |
2530 | |
2531 | if (!do_ssh_init()) |
2532 | return "Protocol initialisation error"; |
2533 | |
4017be6d |
2534 | if (hwnd && WSAAsyncSelect (s, hwnd, WM_NETEVENT, FD_READ | FD_CLOSE) == SOCKET_ERROR) |
374330e2 |
2535 | switch (WSAGetLastError()) { |
2536 | case WSAENETDOWN: return "Network is down"; |
2537 | default: return "WSAAsyncSelect(): unknown error"; |
2538 | } |
2539 | |
2540 | return NULL; |
2541 | } |
2542 | |
2543 | /* |
2544 | * Process a WM_NETEVENT message. Will return 0 if the connection |
2545 | * has closed, or <0 for a socket error. |
2546 | */ |
2547 | static int ssh_msg (WPARAM wParam, LPARAM lParam) { |
2548 | int ret; |
2549 | char buf[256]; |
2550 | |
8ce72d2c |
2551 | /* |
2552 | * Because reading less than the whole of the available pending |
2553 | * data can generate an FD_READ event, we need to allow for the |
2554 | * possibility that FD_READ may arrive with FD_CLOSE already in |
2555 | * the queue; so it's possible that we can get here even with s |
2556 | * invalid. If so, we return 1 and don't worry about it. |
2557 | */ |
2558 | if (s == INVALID_SOCKET) |
2559 | return 1; |
374330e2 |
2560 | |
8d5de777 |
2561 | if (WSAGETSELECTERROR(lParam) != 0) { |
2562 | closesocket(s); |
2563 | s = INVALID_SOCKET; |
374330e2 |
2564 | return -WSAGETSELECTERROR(lParam); |
8d5de777 |
2565 | } |
374330e2 |
2566 | |
2567 | switch (WSAGETSELECTEVENT(lParam)) { |
2568 | case FD_READ: |
8ce72d2c |
2569 | case FD_CLOSE: |
374330e2 |
2570 | ret = recv(s, buf, sizeof(buf), 0); |
2571 | if (ret < 0 && WSAGetLastError() == WSAEWOULDBLOCK) |
2572 | return 1; |
8d5de777 |
2573 | if (ret < 0) { /* any _other_ error */ |
2574 | closesocket(s); |
2575 | s = INVALID_SOCKET; |
374330e2 |
2576 | return -10000-WSAGetLastError(); |
8d5de777 |
2577 | } |
374330e2 |
2578 | if (ret == 0) { |
2579 | s = INVALID_SOCKET; |
8ce72d2c |
2580 | return 0; |
374330e2 |
2581 | } |
2582 | ssh_gotdata (buf, ret); |
85ee8208 |
2583 | if (ssh_state == SSH_STATE_CLOSED) { |
2584 | closesocket(s); |
2585 | s = INVALID_SOCKET; |
2586 | return 0; |
2587 | } |
374330e2 |
2588 | return 1; |
374330e2 |
2589 | } |
2590 | return 1; /* shouldn't happen, but WTF */ |
2591 | } |
2592 | |
2593 | /* |
2594 | * Called to send data down the Telnet connection. |
2595 | */ |
2596 | static void ssh_send (char *buf, int len) { |
2597 | if (s == INVALID_SOCKET) |
2598 | return; |
2599 | |
2600 | ssh_protocol(buf, len, 0); |
2601 | } |
2602 | |
2603 | /* |
2604 | * Called to set the size of the window from Telnet's POV. |
2605 | */ |
2606 | static void ssh_size(void) { |
2607 | switch (ssh_state) { |
2608 | case SSH_STATE_BEFORE_SIZE: |
21248260 |
2609 | case SSH_STATE_CLOSED: |
374330e2 |
2610 | break; /* do nothing */ |
2611 | case SSH_STATE_INTERMED: |
2612 | size_needed = TRUE; /* buffer for later */ |
2613 | break; |
2614 | case SSH_STATE_SESSION: |
fef97f43 |
2615 | if (!cfg.nopty) { |
e5574168 |
2616 | send_packet(SSH1_CMSG_WINDOW_SIZE, |
fb09bf1c |
2617 | PKT_INT, rows, PKT_INT, cols, |
2618 | PKT_INT, 0, PKT_INT, 0, PKT_END); |
fef97f43 |
2619 | } |
374330e2 |
2620 | } |
2621 | } |
2622 | |
2623 | /* |
6abbf9e3 |
2624 | * Send Telnet special codes. TS_EOF is useful for `plink', so you |
2625 | * can send an EOF and collect resulting output (e.g. `plink |
2626 | * hostname sort'). |
374330e2 |
2627 | */ |
2628 | static void ssh_special (Telnet_Special code) { |
6abbf9e3 |
2629 | if (code == TS_EOF) { |
67779be7 |
2630 | if (ssh_version == 1) { |
6abbf9e3 |
2631 | send_packet(SSH1_CMSG_EOF, PKT_END); |
2632 | } else { |
2633 | ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF); |
d211621f |
2634 | ssh2_pkt_adduint32(mainchan->remoteid); |
6abbf9e3 |
2635 | ssh2_pkt_send(); |
2636 | } |
67779be7 |
2637 | logevent("Sent EOF message"); |
ec55b220 |
2638 | } else if (code == TS_PING) { |
2639 | if (ssh_version == 1) { |
2640 | send_packet(SSH1_MSG_IGNORE, PKT_STR, "", PKT_END); |
2641 | } else { |
2642 | ssh2_pkt_init(SSH2_MSG_IGNORE); |
2643 | ssh2_pkt_addstring_start(); |
2644 | ssh2_pkt_send(); |
2645 | } |
6abbf9e3 |
2646 | } else { |
2647 | /* do nothing */ |
2648 | } |
374330e2 |
2649 | } |
2650 | |
8ccc75b0 |
2651 | static SOCKET ssh_socket(void) { return s; } |
2652 | |
2653 | static int ssh_sendok(void) { return ssh_send_ok; } |
fb09bf1c |
2654 | |
374330e2 |
2655 | Backend ssh_backend = { |
2656 | ssh_init, |
2657 | ssh_msg, |
2658 | ssh_send, |
2659 | ssh_size, |
4017be6d |
2660 | ssh_special, |
8ccc75b0 |
2661 | ssh_socket, |
97db3be4 |
2662 | ssh_sendok, |
2663 | 22 |
374330e2 |
2664 | }; |