374330e2 |
1 | #include <stdio.h> |
2 | #include <stdlib.h> |
fb09bf1c |
3 | #include <stdarg.h> |
4 | #include <assert.h> |
374330e2 |
5 | #include <winsock.h> |
6 | |
7 | #include "putty.h" |
dacbd0e8 |
8 | #include "tree234.h" |
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9 | #include "ssh.h" |
10 | #include "scp.h" |
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11 | |
12 | #ifndef FALSE |
13 | #define FALSE 0 |
14 | #endif |
15 | #ifndef TRUE |
16 | #define TRUE 1 |
17 | #endif |
18 | |
fb09bf1c |
19 | #define logevent(s) { logevent(s); \ |
4017be6d |
20 | if (!(flags & FLAG_CONNECTION) && (flags & FLAG_VERBOSE)) \ |
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21 | fprintf(stderr, "%s\n", s); } |
22 | |
e5574168 |
23 | #define SSH1_MSG_DISCONNECT 1 |
24 | #define SSH1_SMSG_PUBLIC_KEY 2 |
25 | #define SSH1_CMSG_SESSION_KEY 3 |
26 | #define SSH1_CMSG_USER 4 |
7cca0d81 |
27 | #define SSH1_CMSG_AUTH_RSA 6 |
28 | #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 |
29 | #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 |
e5574168 |
30 | #define SSH1_CMSG_AUTH_PASSWORD 9 |
31 | #define SSH1_CMSG_REQUEST_PTY 10 |
32 | #define SSH1_CMSG_WINDOW_SIZE 11 |
33 | #define SSH1_CMSG_EXEC_SHELL 12 |
34 | #define SSH1_CMSG_EXEC_CMD 13 |
35 | #define SSH1_SMSG_SUCCESS 14 |
36 | #define SSH1_SMSG_FAILURE 15 |
37 | #define SSH1_CMSG_STDIN_DATA 16 |
38 | #define SSH1_SMSG_STDOUT_DATA 17 |
39 | #define SSH1_SMSG_STDERR_DATA 18 |
40 | #define SSH1_CMSG_EOF 19 |
41 | #define SSH1_SMSG_EXIT_STATUS 20 |
dacbd0e8 |
42 | #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 |
43 | #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 |
44 | #define SSH1_MSG_CHANNEL_DATA 23 |
45 | #define SSH1_MSG_CHANNEL_CLOSE 24 |
46 | #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 |
47 | #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 |
48 | #define SSH1_SMSG_AGENT_OPEN 31 |
e5574168 |
49 | #define SSH1_CMSG_EXIT_CONFIRMATION 33 |
50 | #define SSH1_MSG_IGNORE 32 |
51 | #define SSH1_MSG_DEBUG 36 |
52 | #define SSH1_CMSG_AUTH_TIS 39 |
53 | #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 |
54 | #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 |
18515c51 |
55 | #define SSH1_CMSG_AUTH_CCARD 70 |
56 | #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 |
57 | #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 |
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58 | |
59 | #define SSH1_AUTH_TIS 5 |
18515c51 |
60 | #define SSH1_AUTH_CCARD 16 |
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61 | |
5c58ad2d |
62 | #define SSH_AGENTC_REQUEST_RSA_IDENTITIES 1 |
63 | #define SSH_AGENT_RSA_IDENTITIES_ANSWER 2 |
64 | #define SSH_AGENTC_RSA_CHALLENGE 3 |
65 | #define SSH_AGENT_RSA_RESPONSE 4 |
66 | #define SSH_AGENT_FAILURE 5 |
67 | #define SSH_AGENT_SUCCESS 6 |
68 | #define SSH_AGENTC_ADD_RSA_IDENTITY 7 |
69 | #define SSH_AGENTC_REMOVE_RSA_IDENTITY 8 |
70 | |
e5574168 |
71 | #define SSH2_MSG_DISCONNECT 1 |
72 | #define SSH2_MSG_IGNORE 2 |
73 | #define SSH2_MSG_UNIMPLEMENTED 3 |
74 | #define SSH2_MSG_DEBUG 4 |
75 | #define SSH2_MSG_SERVICE_REQUEST 5 |
76 | #define SSH2_MSG_SERVICE_ACCEPT 6 |
77 | #define SSH2_MSG_KEXINIT 20 |
78 | #define SSH2_MSG_NEWKEYS 21 |
79 | #define SSH2_MSG_KEXDH_INIT 30 |
80 | #define SSH2_MSG_KEXDH_REPLY 31 |
7cca0d81 |
81 | #define SSH2_MSG_USERAUTH_REQUEST 50 |
82 | #define SSH2_MSG_USERAUTH_FAILURE 51 |
83 | #define SSH2_MSG_USERAUTH_SUCCESS 52 |
84 | #define SSH2_MSG_USERAUTH_BANNER 53 |
85 | #define SSH2_MSG_USERAUTH_PK_OK 60 |
86 | #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 |
87 | #define SSH2_MSG_GLOBAL_REQUEST 80 |
88 | #define SSH2_MSG_REQUEST_SUCCESS 81 |
89 | #define SSH2_MSG_REQUEST_FAILURE 82 |
90 | #define SSH2_MSG_CHANNEL_OPEN 90 |
91 | #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 |
92 | #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 |
93 | #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 |
94 | #define SSH2_MSG_CHANNEL_DATA 94 |
95 | #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 |
96 | #define SSH2_MSG_CHANNEL_EOF 96 |
97 | #define SSH2_MSG_CHANNEL_CLOSE 97 |
98 | #define SSH2_MSG_CHANNEL_REQUEST 98 |
99 | #define SSH2_MSG_CHANNEL_SUCCESS 99 |
100 | #define SSH2_MSG_CHANNEL_FAILURE 100 |
101 | |
102 | #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 |
103 | #define SSH2_OPEN_CONNECT_FAILED 2 |
104 | #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 |
105 | #define SSH2_OPEN_RESOURCE_SHORTAGE 4 |
106 | #define SSH2_EXTENDED_DATA_STDERR 1 |
fb09bf1c |
107 | |
108 | #define GET_32BIT(cp) \ |
109 | (((unsigned long)(unsigned char)(cp)[0] << 24) | \ |
110 | ((unsigned long)(unsigned char)(cp)[1] << 16) | \ |
111 | ((unsigned long)(unsigned char)(cp)[2] << 8) | \ |
112 | ((unsigned long)(unsigned char)(cp)[3])) |
113 | |
114 | #define PUT_32BIT(cp, value) { \ |
115 | (cp)[0] = (unsigned char)((value) >> 24); \ |
116 | (cp)[1] = (unsigned char)((value) >> 16); \ |
117 | (cp)[2] = (unsigned char)((value) >> 8); \ |
118 | (cp)[3] = (unsigned char)(value); } |
119 | |
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120 | enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM }; |
972a41c8 |
121 | |
374330e2 |
122 | /* Coroutine mechanics for the sillier bits of the code */ |
123 | #define crBegin1 static int crLine = 0; |
124 | #define crBegin2 switch(crLine) { case 0:; |
125 | #define crBegin crBegin1; crBegin2; |
126 | #define crFinish(z) } crLine = 0; return (z) |
127 | #define crFinishV } crLine = 0; return |
128 | #define crReturn(z) \ |
129 | do {\ |
130 | crLine=__LINE__; return (z); case __LINE__:;\ |
131 | } while (0) |
132 | #define crReturnV \ |
133 | do {\ |
134 | crLine=__LINE__; return; case __LINE__:;\ |
135 | } while (0) |
136 | #define crStop(z) do{ crLine = 0; return (z); }while(0) |
137 | #define crStopV do{ crLine = 0; return; }while(0) |
fb09bf1c |
138 | #define crWaitUntil(c) do { crReturn(0); } while (!(c)) |
7cca0d81 |
139 | #define crWaitUntilV(c) do { crReturnV; } while (!(c)) |
374330e2 |
140 | |
e5574168 |
141 | extern struct ssh_cipher ssh_3des; |
033b4cef |
142 | extern struct ssh_cipher ssh_3des_ssh2; |
e5574168 |
143 | extern struct ssh_cipher ssh_des; |
144 | extern struct ssh_cipher ssh_blowfish; |
145 | |
146 | /* for ssh 2; we miss out single-DES because it isn't supported */ |
033b4cef |
147 | struct ssh_cipher *ciphers[] = { &ssh_3des_ssh2, &ssh_blowfish }; |
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148 | |
149 | extern struct ssh_kex ssh_diffiehellman; |
150 | struct ssh_kex *kex_algs[] = { &ssh_diffiehellman }; |
151 | |
152 | extern struct ssh_hostkey ssh_dss; |
153 | struct ssh_hostkey *hostkey_algs[] = { &ssh_dss }; |
154 | |
155 | extern struct ssh_mac ssh_sha1; |
156 | |
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157 | static SHA_State exhash; |
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158 | |
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159 | static void nullmac_key(unsigned char *key) { } |
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160 | static void nullmac_generate(unsigned char *blk, int len, unsigned long seq) { } |
161 | static int nullmac_verify(unsigned char *blk, int len, unsigned long seq) { return 1; } |
162 | struct ssh_mac ssh_mac_none = { |
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163 | nullmac_key, nullmac_key, nullmac_generate, nullmac_verify, "none", 0 |
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164 | }; |
165 | struct ssh_mac *macs[] = { &ssh_sha1, &ssh_mac_none }; |
166 | |
167 | struct ssh_compress ssh_comp_none = { |
168 | "none" |
169 | }; |
170 | struct ssh_compress *compressions[] = { &ssh_comp_none }; |
171 | |
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172 | static SOCKET s = INVALID_SOCKET; |
173 | |
174 | static unsigned char session_key[32]; |
175 | static struct ssh_cipher *cipher = NULL; |
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176 | static struct ssh_cipher *cscipher = NULL; |
177 | static struct ssh_cipher *sccipher = NULL; |
178 | static struct ssh_mac *csmac = NULL; |
179 | static struct ssh_mac *scmac = NULL; |
180 | static struct ssh_compress *cscomp = NULL; |
181 | static struct ssh_compress *sccomp = NULL; |
182 | static struct ssh_kex *kex = NULL; |
183 | static struct ssh_hostkey *hostkey = NULL; |
85ee8208 |
184 | int (*ssh_get_password)(const char *prompt, char *str, int maxlen) = NULL; |
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185 | |
186 | static char *savedhost; |
8ccc75b0 |
187 | static int ssh_send_ok; |
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188 | |
dacbd0e8 |
189 | /* |
190 | * 2-3-4 tree storing channels. |
191 | */ |
192 | struct ssh_channel { |
193 | int remoteid, localid; |
194 | int type; |
195 | int closes; |
196 | union { |
197 | struct ssh_agent_channel { |
198 | unsigned char *message; |
199 | unsigned char msglen[4]; |
200 | int lensofar, totallen; |
201 | } a; |
202 | } u; |
203 | }; |
204 | static tree234 *ssh_channels; /* indexed by local id */ |
205 | static int ssh_channelcmp(void *av, void *bv) { |
206 | struct ssh_channel *a = (struct ssh_channel *)av; |
207 | struct ssh_channel *b = (struct ssh_channel *)bv; |
208 | if (a->localid < b->localid) return -1; |
209 | if (a->localid > b->localid) return +1; |
210 | return 0; |
211 | } |
212 | static int ssh_channelfind(void *av, void *bv) { |
213 | int *a = (int *)av; |
214 | struct ssh_channel *b = (struct ssh_channel *)bv; |
215 | if (*a < b->localid) return -1; |
216 | if (*a > b->localid) return +1; |
217 | return 0; |
218 | } |
219 | |
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220 | static enum { |
221 | SSH_STATE_BEFORE_SIZE, |
222 | SSH_STATE_INTERMED, |
21248260 |
223 | SSH_STATE_SESSION, |
224 | SSH_STATE_CLOSED |
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225 | } ssh_state = SSH_STATE_BEFORE_SIZE; |
226 | |
227 | static int size_needed = FALSE; |
228 | |
229 | static void s_write (char *buf, int len) { |
230 | while (len > 0) { |
231 | int i = send (s, buf, len, 0); |
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232 | noise_ultralight(i); |
233 | if (i <= 0) |
234 | fatalbox("Lost connection while sending"); |
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235 | if (i > 0) |
236 | len -= i, buf += i; |
237 | } |
238 | } |
239 | |
240 | static int s_read (char *buf, int len) { |
241 | int ret = 0; |
242 | while (len > 0) { |
243 | int i = recv (s, buf, len, 0); |
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244 | noise_ultralight(i); |
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245 | if (i > 0) |
246 | len -= i, buf += i, ret += i; |
247 | else |
248 | return i; |
249 | } |
250 | return ret; |
251 | } |
252 | |
253 | static void c_write (char *buf, int len) { |
4017be6d |
254 | if (!(flags & FLAG_CONNECTION)) { |
255 | int i; |
256 | for (i = 0; i < len; i++) |
257 | if (buf[i] != '\r') |
258 | fputc(buf[i], stderr); |
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259 | return; |
260 | } |
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261 | while (len--) |
262 | c_write1(*buf++); |
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263 | } |
264 | |
265 | struct Packet { |
266 | long length; |
267 | int type; |
374330e2 |
268 | unsigned char *data; |
269 | unsigned char *body; |
e5574168 |
270 | long savedpos; |
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271 | long maxlen; |
272 | }; |
273 | |
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274 | static struct Packet pktin = { 0, 0, NULL, NULL, 0 }; |
275 | static struct Packet pktout = { 0, 0, NULL, NULL, 0 }; |
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276 | |
6abbf9e3 |
277 | static int ssh_version; |
e5574168 |
278 | static void (*ssh_protocol)(unsigned char *in, int inlen, int ispkt); |
279 | static void ssh1_protocol(unsigned char *in, int inlen, int ispkt); |
280 | static void ssh2_protocol(unsigned char *in, int inlen, int ispkt); |
374330e2 |
281 | static void ssh_size(void); |
282 | |
e5574168 |
283 | static int (*s_rdpkt)(unsigned char **data, int *datalen); |
fb09bf1c |
284 | |
285 | /* |
286 | * Collect incoming data in the incoming packet buffer. |
e5574168 |
287 | * Decipher and verify the packet when it is completely read. |
288 | * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets. |
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289 | * Update the *data and *datalen variables. |
290 | * Return the additional nr of bytes needed, or 0 when |
291 | * a complete packet is available. |
292 | */ |
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293 | static int ssh1_rdpkt(unsigned char **data, int *datalen) |
fb09bf1c |
294 | { |
295 | static long len, pad, biglen, to_read; |
572f871e |
296 | static unsigned long realcrc, gotcrc; |
fb09bf1c |
297 | static unsigned char *p; |
298 | static int i; |
374330e2 |
299 | |
300 | crBegin; |
374330e2 |
301 | |
fb09bf1c |
302 | next_packet: |
37508af4 |
303 | |
fb09bf1c |
304 | pktin.type = 0; |
305 | pktin.length = 0; |
374330e2 |
306 | |
fb09bf1c |
307 | for (i = len = 0; i < 4; i++) { |
308 | while ((*datalen) == 0) |
309 | crReturn(4-i); |
310 | len = (len << 8) + **data; |
311 | (*data)++, (*datalen)--; |
312 | } |
374330e2 |
313 | |
fb09bf1c |
314 | #ifdef FWHACK |
315 | if (len == 0x52656d6f) { /* "Remo"te server has closed ... */ |
316 | len = 0x300; /* big enough to carry to end */ |
317 | } |
318 | #endif |
374330e2 |
319 | |
fb09bf1c |
320 | pad = 8 - (len % 8); |
321 | biglen = len + pad; |
322 | pktin.length = len - 5; |
323 | |
324 | if (pktin.maxlen < biglen) { |
325 | pktin.maxlen = biglen; |
e5574168 |
326 | pktin.data = (pktin.data == NULL ? malloc(biglen+APIEXTRA) : |
327 | realloc(pktin.data, biglen+APIEXTRA)); |
fb09bf1c |
328 | if (!pktin.data) |
329 | fatalbox("Out of memory"); |
330 | } |
374330e2 |
331 | |
fb09bf1c |
332 | to_read = biglen; |
333 | p = pktin.data; |
334 | while (to_read > 0) { |
335 | static int chunk; |
336 | chunk = to_read; |
337 | while ((*datalen) == 0) |
338 | crReturn(to_read); |
339 | if (chunk > (*datalen)) |
340 | chunk = (*datalen); |
341 | memcpy(p, *data, chunk); |
342 | *data += chunk; |
343 | *datalen -= chunk; |
344 | p += chunk; |
345 | to_read -= chunk; |
346 | } |
374330e2 |
347 | |
fb09bf1c |
348 | if (cipher) |
349 | cipher->decrypt(pktin.data, biglen); |
374330e2 |
350 | |
fb09bf1c |
351 | pktin.type = pktin.data[pad]; |
352 | pktin.body = pktin.data + pad + 1; |
374330e2 |
353 | |
fb09bf1c |
354 | realcrc = crc32(pktin.data, biglen-4); |
355 | gotcrc = GET_32BIT(pktin.data+biglen-4); |
356 | if (gotcrc != realcrc) { |
357 | fatalbox("Incorrect CRC received on packet"); |
358 | } |
572f871e |
359 | |
e5574168 |
360 | if (pktin.type == SSH1_SMSG_STDOUT_DATA || |
361 | pktin.type == SSH1_SMSG_STDERR_DATA || |
362 | pktin.type == SSH1_MSG_DEBUG || |
18515c51 |
363 | pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE || |
364 | pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) { |
fb09bf1c |
365 | long strlen = GET_32BIT(pktin.body); |
366 | if (strlen + 4 != pktin.length) |
367 | fatalbox("Received data packet with bogus string length"); |
368 | } |
369 | |
e5574168 |
370 | if (pktin.type == SSH1_MSG_DEBUG) { |
fb09bf1c |
371 | /* log debug message */ |
372 | char buf[80]; |
373 | int strlen = GET_32BIT(pktin.body); |
374 | strcpy(buf, "Remote: "); |
375 | if (strlen > 70) strlen = 70; |
376 | memcpy(buf+8, pktin.body+4, strlen); |
377 | buf[8+strlen] = '\0'; |
378 | logevent(buf); |
379 | goto next_packet; |
e5574168 |
380 | } else if (pktin.type == SSH1_MSG_IGNORE) { |
fb09bf1c |
381 | /* do nothing */ |
382 | goto next_packet; |
383 | } |
384 | |
385 | crFinish(0); |
386 | } |
387 | |
e5574168 |
388 | static int ssh2_rdpkt(unsigned char **data, int *datalen) |
389 | { |
390 | static long len, pad, payload, packetlen, maclen; |
391 | static int i; |
392 | static int cipherblk; |
393 | static unsigned long incoming_sequence = 0; |
394 | |
395 | crBegin; |
396 | |
397 | next_packet: |
398 | |
399 | pktin.type = 0; |
400 | pktin.length = 0; |
401 | |
402 | if (cipher) |
403 | cipherblk = cipher->blksize; |
404 | else |
405 | cipherblk = 8; |
406 | if (cipherblk < 8) |
407 | cipherblk = 8; |
408 | |
409 | if (pktin.maxlen < cipherblk) { |
410 | pktin.maxlen = cipherblk; |
411 | pktin.data = (pktin.data == NULL ? malloc(cipherblk+APIEXTRA) : |
412 | realloc(pktin.data, cipherblk+APIEXTRA)); |
413 | if (!pktin.data) |
414 | fatalbox("Out of memory"); |
415 | } |
416 | |
417 | /* |
418 | * Acquire and decrypt the first block of the packet. This will |
419 | * contain the length and padding details. |
420 | */ |
421 | for (i = len = 0; i < cipherblk; i++) { |
422 | while ((*datalen) == 0) |
423 | crReturn(cipherblk-i); |
424 | pktin.data[i] = *(*data)++; |
425 | (*datalen)--; |
426 | } |
427 | #ifdef FWHACK |
428 | if (!memcmp(pktin.data, "Remo", 4)) {/* "Remo"te server has closed ... */ |
429 | /* FIXME */ |
430 | } |
431 | #endif |
432 | if (sccipher) |
433 | sccipher->decrypt(pktin.data, cipherblk); |
434 | |
435 | /* |
436 | * Now get the length and padding figures. |
437 | */ |
438 | len = GET_32BIT(pktin.data); |
439 | pad = pktin.data[4]; |
440 | |
441 | /* |
442 | * This enables us to deduce the payload length. |
443 | */ |
444 | payload = len - pad - 1; |
445 | |
446 | pktin.length = payload + 5; |
447 | |
448 | /* |
449 | * So now we can work out the total packet length. |
450 | */ |
451 | packetlen = len + 4; |
452 | maclen = scmac ? scmac->len : 0; |
453 | |
454 | /* |
455 | * Adjust memory allocation if packet is too big. |
456 | */ |
59dcd2a8 |
457 | if (pktin.maxlen < packetlen+maclen) { |
458 | pktin.maxlen = packetlen+maclen; |
459 | pktin.data = (pktin.data == NULL ? malloc(pktin.maxlen+APIEXTRA) : |
460 | realloc(pktin.data, pktin.maxlen+APIEXTRA)); |
e5574168 |
461 | if (!pktin.data) |
462 | fatalbox("Out of memory"); |
463 | } |
464 | |
465 | /* |
466 | * Read and decrypt the remainder of the packet. |
467 | */ |
468 | for (i = cipherblk; i < packetlen + maclen; i++) { |
469 | while ((*datalen) == 0) |
470 | crReturn(packetlen + maclen - i); |
471 | pktin.data[i] = *(*data)++; |
472 | (*datalen)--; |
473 | } |
474 | /* Decrypt everything _except_ the MAC. */ |
475 | if (sccipher) |
476 | sccipher->decrypt(pktin.data + cipherblk, packetlen - cipherblk); |
477 | |
7cca0d81 |
478 | #if 0 |
d39f364a |
479 | debug(("Got packet len=%d pad=%d\r\n", len, pad)); |
480 | for (i = 0; i < packetlen; i++) |
481 | debug((" %02x", (unsigned char)pktin.data[i])); |
482 | debug(("\r\n")); |
7cca0d81 |
483 | #endif |
d39f364a |
484 | |
e5574168 |
485 | /* |
486 | * Check the MAC. |
487 | */ |
033b4cef |
488 | if (scmac && !scmac->verify(pktin.data, len+4, incoming_sequence)) |
e5574168 |
489 | fatalbox("Incorrect MAC received on packet"); |
033b4cef |
490 | incoming_sequence++; /* whether or not we MACed */ |
e5574168 |
491 | |
492 | pktin.savedpos = 6; |
493 | pktin.type = pktin.data[5]; |
e5574168 |
494 | |
7cca0d81 |
495 | if (pktin.type == SSH2_MSG_IGNORE || pktin.type == SSH2_MSG_DEBUG) |
496 | goto next_packet; /* FIXME: print DEBUG message */ |
e5574168 |
497 | |
498 | crFinish(0); |
499 | } |
500 | |
fb09bf1c |
501 | static void ssh_gotdata(unsigned char *data, int datalen) |
502 | { |
503 | while (datalen > 0) { |
85ee8208 |
504 | if ( s_rdpkt(&data, &datalen) == 0 ) { |
374330e2 |
505 | ssh_protocol(NULL, 0, 1); |
85ee8208 |
506 | if (ssh_state == SSH_STATE_CLOSED) { |
507 | return; |
508 | } |
509 | } |
374330e2 |
510 | } |
374330e2 |
511 | } |
512 | |
fb09bf1c |
513 | |
374330e2 |
514 | static void s_wrpkt_start(int type, int len) { |
515 | int pad, biglen; |
516 | |
517 | len += 5; /* type and CRC */ |
518 | pad = 8 - (len%8); |
519 | biglen = len + pad; |
520 | |
521 | pktout.length = len-5; |
522 | if (pktout.maxlen < biglen) { |
523 | pktout.maxlen = biglen; |
8f203108 |
524 | #ifdef MSCRYPTOAPI |
fb09bf1c |
525 | /* Allocate enough buffer space for extra block |
8f203108 |
526 | * for MS CryptEncrypt() */ |
fb09bf1c |
527 | pktout.data = (pktout.data == NULL ? malloc(biglen+12) : |
528 | realloc(pktout.data, biglen+12)); |
8f203108 |
529 | #else |
c1f5f956 |
530 | pktout.data = (pktout.data == NULL ? malloc(biglen+4) : |
531 | realloc(pktout.data, biglen+4)); |
8f203108 |
532 | #endif |
374330e2 |
533 | if (!pktout.data) |
534 | fatalbox("Out of memory"); |
535 | } |
536 | |
537 | pktout.type = type; |
538 | pktout.body = pktout.data+4+pad+1; |
539 | } |
540 | |
541 | static void s_wrpkt(void) { |
542 | int pad, len, biglen, i; |
543 | unsigned long crc; |
544 | |
545 | len = pktout.length + 5; /* type and CRC */ |
546 | pad = 8 - (len%8); |
547 | biglen = len + pad; |
548 | |
549 | pktout.body[-1] = pktout.type; |
550 | for (i=0; i<pad; i++) |
551 | pktout.data[i+4] = random_byte(); |
552 | crc = crc32(pktout.data+4, biglen-4); |
fb09bf1c |
553 | PUT_32BIT(pktout.data+biglen, crc); |
554 | PUT_32BIT(pktout.data, len); |
374330e2 |
555 | |
556 | if (cipher) |
557 | cipher->encrypt(pktout.data+4, biglen); |
558 | |
559 | s_write(pktout.data, biglen+4); |
560 | } |
561 | |
fb09bf1c |
562 | /* |
563 | * Construct a packet with the specified contents and |
564 | * send it to the server. |
565 | */ |
566 | static void send_packet(int pkttype, ...) |
567 | { |
568 | va_list args; |
569 | unsigned char *p, *argp, argchar; |
570 | unsigned long argint; |
571 | int pktlen, argtype, arglen; |
7cca0d81 |
572 | Bignum bn; |
fb09bf1c |
573 | |
574 | pktlen = 0; |
575 | va_start(args, pkttype); |
576 | while ((argtype = va_arg(args, int)) != PKT_END) { |
577 | switch (argtype) { |
578 | case PKT_INT: |
579 | (void) va_arg(args, int); |
580 | pktlen += 4; |
581 | break; |
582 | case PKT_CHAR: |
583 | (void) va_arg(args, char); |
584 | pktlen++; |
585 | break; |
586 | case PKT_DATA: |
587 | (void) va_arg(args, unsigned char *); |
588 | arglen = va_arg(args, int); |
589 | pktlen += arglen; |
590 | break; |
591 | case PKT_STR: |
592 | argp = va_arg(args, unsigned char *); |
593 | arglen = strlen(argp); |
594 | pktlen += 4 + arglen; |
595 | break; |
7cca0d81 |
596 | case PKT_BIGNUM: |
597 | bn = va_arg(args, Bignum); |
5c58ad2d |
598 | pktlen += ssh1_bignum_length(bn); |
7cca0d81 |
599 | break; |
fb09bf1c |
600 | default: |
601 | assert(0); |
602 | } |
603 | } |
604 | va_end(args); |
605 | |
606 | s_wrpkt_start(pkttype, pktlen); |
607 | p = pktout.body; |
608 | |
609 | va_start(args, pkttype); |
610 | while ((argtype = va_arg(args, int)) != PKT_END) { |
611 | switch (argtype) { |
612 | case PKT_INT: |
613 | argint = va_arg(args, int); |
614 | PUT_32BIT(p, argint); |
615 | p += 4; |
616 | break; |
617 | case PKT_CHAR: |
618 | argchar = va_arg(args, unsigned char); |
619 | *p = argchar; |
620 | p++; |
621 | break; |
622 | case PKT_DATA: |
623 | argp = va_arg(args, unsigned char *); |
624 | arglen = va_arg(args, int); |
625 | memcpy(p, argp, arglen); |
626 | p += arglen; |
627 | break; |
628 | case PKT_STR: |
629 | argp = va_arg(args, unsigned char *); |
630 | arglen = strlen(argp); |
631 | PUT_32BIT(p, arglen); |
632 | memcpy(p + 4, argp, arglen); |
633 | p += 4 + arglen; |
634 | break; |
7cca0d81 |
635 | case PKT_BIGNUM: |
636 | bn = va_arg(args, Bignum); |
5c58ad2d |
637 | p += ssh1_write_bignum(p, bn); |
7cca0d81 |
638 | break; |
fb09bf1c |
639 | } |
640 | } |
641 | va_end(args); |
642 | |
643 | s_wrpkt(); |
644 | } |
645 | |
646 | |
647 | /* |
648 | * Connect to specified host and port. |
649 | * Returns an error message, or NULL on success. |
650 | * Also places the canonical host name into `realhost'. |
651 | */ |
652 | static char *connect_to_host(char *host, int port, char **realhost) |
653 | { |
654 | SOCKADDR_IN addr; |
655 | struct hostent *h; |
656 | unsigned long a; |
657 | #ifdef FWHACK |
658 | char *FWhost; |
659 | int FWport; |
660 | #endif |
661 | |
662 | savedhost = malloc(1+strlen(host)); |
663 | if (!savedhost) |
664 | fatalbox("Out of memory"); |
665 | strcpy(savedhost, host); |
666 | |
667 | if (port < 0) |
668 | port = 22; /* default ssh port */ |
669 | |
670 | #ifdef FWHACK |
671 | FWhost = host; |
672 | FWport = port; |
673 | host = FWSTR; |
674 | port = 23; |
675 | #endif |
676 | |
677 | /* |
678 | * Try to find host. |
679 | */ |
680 | if ( (a = inet_addr(host)) == (unsigned long) INADDR_NONE) { |
681 | if ( (h = gethostbyname(host)) == NULL) |
682 | switch (WSAGetLastError()) { |
683 | case WSAENETDOWN: return "Network is down"; |
684 | case WSAHOST_NOT_FOUND: case WSANO_DATA: |
685 | return "Host does not exist"; |
686 | case WSATRY_AGAIN: return "Host not found"; |
687 | default: return "gethostbyname: unknown error"; |
688 | } |
689 | memcpy (&a, h->h_addr, sizeof(a)); |
690 | *realhost = h->h_name; |
691 | } else |
692 | *realhost = host; |
693 | #ifdef FWHACK |
694 | *realhost = FWhost; |
695 | #endif |
696 | a = ntohl(a); |
697 | |
698 | /* |
699 | * Open socket. |
700 | */ |
701 | s = socket(AF_INET, SOCK_STREAM, 0); |
702 | if (s == INVALID_SOCKET) |
703 | switch (WSAGetLastError()) { |
704 | case WSAENETDOWN: return "Network is down"; |
705 | case WSAEAFNOSUPPORT: return "TCP/IP support not present"; |
706 | default: return "socket(): unknown error"; |
707 | } |
708 | |
709 | /* |
710 | * Bind to local address. |
711 | */ |
712 | addr.sin_family = AF_INET; |
713 | addr.sin_addr.s_addr = htonl(INADDR_ANY); |
714 | addr.sin_port = htons(0); |
715 | if (bind (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR) |
716 | switch (WSAGetLastError()) { |
717 | case WSAENETDOWN: return "Network is down"; |
718 | default: return "bind(): unknown error"; |
719 | } |
720 | |
721 | /* |
722 | * Connect to remote address. |
723 | */ |
724 | addr.sin_addr.s_addr = htonl(a); |
725 | addr.sin_port = htons((short)port); |
726 | if (connect (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR) |
727 | switch (WSAGetLastError()) { |
728 | case WSAENETDOWN: return "Network is down"; |
729 | case WSAECONNREFUSED: return "Connection refused"; |
730 | case WSAENETUNREACH: return "Network is unreachable"; |
731 | case WSAEHOSTUNREACH: return "No route to host"; |
732 | default: return "connect(): unknown error"; |
733 | } |
734 | |
735 | #ifdef FWHACK |
736 | send(s, "connect ", 8, 0); |
737 | send(s, FWhost, strlen(FWhost), 0); |
738 | { |
739 | char buf[20]; |
740 | sprintf(buf, " %d\n", FWport); |
741 | send (s, buf, strlen(buf), 0); |
742 | } |
743 | #endif |
744 | |
745 | return NULL; |
746 | } |
747 | |
9697bfd2 |
748 | static int ssh_versioncmp(char *a, char *b) { |
749 | char *ae, *be; |
750 | unsigned long av, bv; |
751 | |
43aa02a7 |
752 | av = strtoul(a, &ae, 10); |
753 | bv = strtoul(b, &be, 10); |
9697bfd2 |
754 | if (av != bv) return (av < bv ? -1 : +1); |
755 | if (*ae == '.') ae++; |
756 | if (*be == '.') be++; |
43aa02a7 |
757 | av = strtoul(ae, &ae, 10); |
758 | bv = strtoul(be, &be, 10); |
9697bfd2 |
759 | if (av != bv) return (av < bv ? -1 : +1); |
760 | return 0; |
761 | } |
762 | |
e5574168 |
763 | |
764 | /* |
765 | * Utility routine for putting an SSH-protocol `string' into a SHA |
766 | * state. |
767 | */ |
768 | #include <stdio.h> |
769 | void sha_string(SHA_State *s, void *str, int len) { |
770 | unsigned char lenblk[4]; |
e5574168 |
771 | PUT_32BIT(lenblk, len); |
e5574168 |
772 | SHA_Bytes(s, lenblk, 4); |
e5574168 |
773 | SHA_Bytes(s, str, len); |
774 | } |
775 | |
7cca0d81 |
776 | /* |
777 | * SSH2 packet construction functions. |
778 | */ |
779 | void ssh2_pkt_adddata(void *data, int len) { |
780 | pktout.length += len; |
781 | if (pktout.maxlen < pktout.length) { |
782 | pktout.maxlen = pktout.length + 256; |
783 | pktout.data = (pktout.data == NULL ? malloc(pktout.maxlen+APIEXTRA) : |
784 | realloc(pktout.data, pktout.maxlen+APIEXTRA)); |
785 | if (!pktout.data) |
786 | fatalbox("Out of memory"); |
787 | } |
788 | memcpy(pktout.data+pktout.length-len, data, len); |
789 | } |
790 | void ssh2_pkt_addbyte(unsigned char byte) { |
791 | ssh2_pkt_adddata(&byte, 1); |
792 | } |
793 | void ssh2_pkt_init(int pkt_type) { |
794 | pktout.length = 5; |
795 | ssh2_pkt_addbyte((unsigned char)pkt_type); |
796 | } |
797 | void ssh2_pkt_addbool(unsigned char value) { |
798 | ssh2_pkt_adddata(&value, 1); |
799 | } |
800 | void ssh2_pkt_adduint32(unsigned long value) { |
801 | unsigned char x[4]; |
802 | PUT_32BIT(x, value); |
803 | ssh2_pkt_adddata(x, 4); |
804 | } |
805 | void ssh2_pkt_addstring_start(void) { |
806 | ssh2_pkt_adduint32(0); |
807 | pktout.savedpos = pktout.length; |
808 | } |
809 | void ssh2_pkt_addstring_str(char *data) { |
810 | ssh2_pkt_adddata(data, strlen(data)); |
811 | PUT_32BIT(pktout.data + pktout.savedpos - 4, |
812 | pktout.length - pktout.savedpos); |
813 | } |
814 | void ssh2_pkt_addstring_data(char *data, int len) { |
815 | ssh2_pkt_adddata(data, len); |
816 | PUT_32BIT(pktout.data + pktout.savedpos - 4, |
817 | pktout.length - pktout.savedpos); |
818 | } |
819 | void ssh2_pkt_addstring(char *data) { |
820 | ssh2_pkt_addstring_start(); |
821 | ssh2_pkt_addstring_str(data); |
822 | } |
823 | char *ssh2_mpint_fmt(Bignum b, int *len) { |
824 | unsigned char *p; |
825 | int i, n = b[0]; |
826 | p = malloc(n * 2 + 1); |
827 | if (!p) |
828 | fatalbox("out of memory"); |
829 | p[0] = 0; |
830 | for (i = 0; i < n; i++) { |
831 | p[i*2+1] = (b[n-i] >> 8) & 0xFF; |
832 | p[i*2+2] = (b[n-i] ) & 0xFF; |
833 | } |
834 | i = 0; |
835 | while (p[i] == 0 && (p[i+1] & 0x80) == 0) |
836 | i++; |
837 | memmove(p, p+i, n*2+1-i); |
838 | *len = n*2+1-i; |
839 | return p; |
840 | } |
841 | void ssh2_pkt_addmp(Bignum b) { |
842 | unsigned char *p; |
843 | int len; |
844 | p = ssh2_mpint_fmt(b, &len); |
845 | ssh2_pkt_addstring_start(); |
846 | ssh2_pkt_addstring_data(p, len); |
847 | free(p); |
848 | } |
849 | void ssh2_pkt_send(void) { |
850 | int cipherblk, maclen, padding, i; |
851 | static unsigned long outgoing_sequence = 0; |
852 | |
853 | /* |
854 | * Add padding. At least four bytes, and must also bring total |
855 | * length (minus MAC) up to a multiple of the block size. |
856 | */ |
857 | cipherblk = cipher ? cipher->blksize : 8; /* block size */ |
858 | cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */ |
859 | padding = 4; |
860 | padding += (cipherblk - (pktout.length + padding) % cipherblk) % cipherblk; |
861 | pktout.data[4] = padding; |
862 | for (i = 0; i < padding; i++) |
863 | pktout.data[pktout.length + i] = random_byte(); |
864 | PUT_32BIT(pktout.data, pktout.length + padding - 4); |
865 | if (csmac) |
866 | csmac->generate(pktout.data, pktout.length + padding, |
867 | outgoing_sequence); |
868 | outgoing_sequence++; /* whether or not we MACed */ |
869 | |
870 | #if 0 |
871 | debug(("Sending packet len=%d\r\n", pktout.length+padding)); |
872 | for (i = 0; i < pktout.length+padding; i++) |
873 | debug((" %02x", (unsigned char)pktout.data[i])); |
874 | debug(("\r\n")); |
875 | #endif |
876 | |
877 | if (cscipher) |
878 | cscipher->encrypt(pktout.data, pktout.length + padding); |
879 | maclen = csmac ? csmac->len : 0; |
880 | |
881 | s_write(pktout.data, pktout.length + padding + maclen); |
882 | } |
883 | |
884 | #if 0 |
885 | void bndebug(char *string, Bignum b) { |
886 | unsigned char *p; |
887 | int i, len; |
888 | p = ssh2_mpint_fmt(b, &len); |
889 | debug(("%s", string)); |
890 | for (i = 0; i < len; i++) |
891 | debug((" %02x", p[i])); |
892 | debug(("\r\n")); |
893 | free(p); |
894 | } |
895 | #endif |
896 | |
897 | void sha_mpint(SHA_State *s, Bignum b) { |
898 | unsigned char *p; |
899 | int len; |
900 | p = ssh2_mpint_fmt(b, &len); |
901 | sha_string(s, p, len); |
902 | free(p); |
903 | } |
904 | |
905 | /* |
906 | * SSH2 packet decode functions. |
907 | */ |
908 | unsigned long ssh2_pkt_getuint32(void) { |
909 | unsigned long value; |
910 | if (pktin.length - pktin.savedpos < 4) |
911 | return 0; /* arrgh, no way to decline (FIXME?) */ |
912 | value = GET_32BIT(pktin.data+pktin.savedpos); |
913 | pktin.savedpos += 4; |
914 | return value; |
915 | } |
916 | void ssh2_pkt_getstring(char **p, int *length) { |
917 | *p = NULL; |
918 | if (pktin.length - pktin.savedpos < 4) |
919 | return; |
920 | *length = GET_32BIT(pktin.data+pktin.savedpos); |
921 | pktin.savedpos += 4; |
922 | if (pktin.length - pktin.savedpos < *length) |
923 | return; |
924 | *p = pktin.data+pktin.savedpos; |
925 | pktin.savedpos += *length; |
926 | } |
927 | Bignum ssh2_pkt_getmp(void) { |
928 | char *p; |
929 | int i, j, length; |
930 | Bignum b; |
931 | |
932 | ssh2_pkt_getstring(&p, &length); |
933 | if (!p) |
934 | return NULL; |
935 | if (p[0] & 0x80) |
936 | fatalbox("internal error: Can't handle negative mpints"); |
937 | b = newbn((length+1)/2); |
938 | for (i = 0; i < length; i++) { |
939 | j = length - 1 - i; |
940 | if (j & 1) |
941 | b[j/2+1] |= ((unsigned char)p[i]) << 8; |
942 | else |
943 | b[j/2+1] |= ((unsigned char)p[i]); |
944 | } |
945 | return b; |
946 | } |
947 | |
374330e2 |
948 | static int do_ssh_init(void) { |
c5e9c988 |
949 | char c, *vsp; |
374330e2 |
950 | char version[10]; |
c5e9c988 |
951 | char vstring[80]; |
952 | char vlog[sizeof(vstring)+20]; |
374330e2 |
953 | int i; |
954 | |
955 | #ifdef FWHACK |
956 | i = 0; |
957 | while (s_read(&c, 1) == 1) { |
958 | if (c == 'S' && i < 2) i++; |
959 | else if (c == 'S' && i == 2) i = 2; |
960 | else if (c == 'H' && i == 2) break; |
961 | else i = 0; |
962 | } |
963 | #else |
964 | if (s_read(&c,1) != 1 || c != 'S') return 0; |
965 | if (s_read(&c,1) != 1 || c != 'S') return 0; |
966 | if (s_read(&c,1) != 1 || c != 'H') return 0; |
967 | #endif |
c5e9c988 |
968 | strcpy(vstring, "SSH-"); |
969 | vsp = vstring+4; |
374330e2 |
970 | if (s_read(&c,1) != 1 || c != '-') return 0; |
971 | i = 0; |
972 | while (1) { |
973 | if (s_read(&c,1) != 1) |
974 | return 0; |
c5e9c988 |
975 | if (vsp < vstring+sizeof(vstring)-1) |
976 | *vsp++ = c; |
374330e2 |
977 | if (i >= 0) { |
978 | if (c == '-') { |
979 | version[i] = '\0'; |
980 | i = -1; |
981 | } else if (i < sizeof(version)-1) |
982 | version[i++] = c; |
983 | } |
984 | else if (c == '\n') |
985 | break; |
986 | } |
987 | |
c5e9c988 |
988 | *vsp = 0; |
989 | sprintf(vlog, "Server version: %s", vstring); |
990 | vlog[strcspn(vlog, "\r\n")] = '\0'; |
991 | logevent(vlog); |
992 | |
adf799dd |
993 | /* |
994 | * Server version "1.99" means we can choose whether we use v1 |
995 | * or v2 protocol. Choice is based on cfg.sshprot. |
996 | */ |
997 | if (ssh_versioncmp(version, cfg.sshprot == 1 ? "2.0" : "1.99") >= 0) { |
e5574168 |
998 | /* |
999 | * This is a v2 server. Begin v2 protocol. |
1000 | */ |
1001 | char *verstring = "SSH-2.0-PuTTY"; |
1002 | SHA_Init(&exhash); |
1003 | /* |
1004 | * Hash our version string and their version string. |
1005 | */ |
1006 | sha_string(&exhash, verstring, strlen(verstring)); |
1007 | sha_string(&exhash, vstring, strcspn(vstring, "\r\n")); |
1008 | sprintf(vstring, "%s\n", verstring); |
1009 | sprintf(vlog, "We claim version: %s", verstring); |
1010 | logevent(vlog); |
1011 | logevent("Using SSH protocol version 2"); |
1012 | s_write(vstring, strlen(vstring)); |
1013 | ssh_protocol = ssh2_protocol; |
6abbf9e3 |
1014 | ssh_version = 2; |
e5574168 |
1015 | s_rdpkt = ssh2_rdpkt; |
1016 | } else { |
1017 | /* |
1018 | * This is a v1 server. Begin v1 protocol. |
1019 | */ |
1020 | sprintf(vstring, "SSH-%s-PuTTY\n", |
1021 | (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5")); |
1022 | sprintf(vlog, "We claim version: %s", vstring); |
1023 | vlog[strcspn(vlog, "\r\n")] = '\0'; |
1024 | logevent(vlog); |
1025 | logevent("Using SSH protocol version 1"); |
1026 | s_write(vstring, strlen(vstring)); |
1027 | ssh_protocol = ssh1_protocol; |
6abbf9e3 |
1028 | ssh_version = 1; |
e5574168 |
1029 | s_rdpkt = ssh1_rdpkt; |
1030 | } |
8ccc75b0 |
1031 | ssh_send_ok = 0; |
fef97f43 |
1032 | return 1; |
374330e2 |
1033 | } |
1034 | |
fb09bf1c |
1035 | /* |
1036 | * Handle the key exchange and user authentication phases. |
1037 | */ |
e5574168 |
1038 | static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) |
fb09bf1c |
1039 | { |
374330e2 |
1040 | int i, j, len; |
374330e2 |
1041 | unsigned char *rsabuf, *keystr1, *keystr2; |
1042 | unsigned char cookie[8]; |
1043 | struct RSAKey servkey, hostkey; |
1044 | struct MD5Context md5c; |
ccbfb941 |
1045 | static unsigned long supported_ciphers_mask, supported_auths_mask; |
7cca0d81 |
1046 | static int tried_publickey; |
1047 | static unsigned char session_id[16]; |
bea1ef5f |
1048 | int cipher_type; |
374330e2 |
1049 | |
374330e2 |
1050 | crBegin; |
1051 | |
fb09bf1c |
1052 | if (!ispkt) crWaitUntil(ispkt); |
374330e2 |
1053 | |
e5574168 |
1054 | if (pktin.type != SSH1_SMSG_PUBLIC_KEY) |
374330e2 |
1055 | fatalbox("Public key packet not received"); |
1056 | |
c5e9c988 |
1057 | logevent("Received public keys"); |
374330e2 |
1058 | |
c5e9c988 |
1059 | memcpy(cookie, pktin.body, 8); |
374330e2 |
1060 | |
7cca0d81 |
1061 | i = makekey(pktin.body+8, &servkey, &keystr1, 0); |
1062 | j = makekey(pktin.body+8+i, &hostkey, &keystr2, 0); |
374330e2 |
1063 | |
c5e9c988 |
1064 | /* |
1065 | * Hash the host key and print the hash in the log box. Just as |
1066 | * a last resort in case the registry's host key checking is |
1067 | * compromised, we'll allow the user some ability to verify |
1068 | * host keys by eye. |
1069 | */ |
1070 | MD5Init(&md5c); |
1071 | MD5Update(&md5c, keystr2, hostkey.bytes); |
1072 | MD5Final(session_id, &md5c); |
1073 | { |
1074 | char logmsg[80]; |
1075 | int i; |
1076 | logevent("Host key MD5 is:"); |
1077 | strcpy(logmsg, " "); |
1078 | for (i = 0; i < 16; i++) |
1079 | sprintf(logmsg+strlen(logmsg), "%02x", session_id[i]); |
1080 | logevent(logmsg); |
1081 | } |
1082 | |
fb09bf1c |
1083 | supported_ciphers_mask = GET_32BIT(pktin.body+12+i+j); |
1084 | supported_auths_mask = GET_32BIT(pktin.body+16+i+j); |
bea1ef5f |
1085 | |
c5e9c988 |
1086 | MD5Init(&md5c); |
374330e2 |
1087 | MD5Update(&md5c, keystr2, hostkey.bytes); |
1088 | MD5Update(&md5c, keystr1, servkey.bytes); |
1089 | MD5Update(&md5c, pktin.body, 8); |
374330e2 |
1090 | MD5Final(session_id, &md5c); |
1091 | |
1092 | for (i=0; i<32; i++) |
1093 | session_key[i] = random_byte(); |
1094 | |
1095 | len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes); |
1096 | |
1097 | rsabuf = malloc(len); |
1098 | if (!rsabuf) |
1099 | fatalbox("Out of memory"); |
1100 | |
89ee5268 |
1101 | /* |
1102 | * Verify the host key. |
1103 | */ |
1104 | { |
1105 | /* |
1106 | * First format the key into a string. |
1107 | */ |
1108 | int len = rsastr_len(&hostkey); |
1109 | char *keystr = malloc(len); |
1110 | if (!keystr) |
1111 | fatalbox("Out of memory"); |
1112 | rsastr_fmt(keystr, &hostkey); |
1113 | verify_ssh_host_key(savedhost, keystr); |
1114 | free(keystr); |
1115 | } |
374330e2 |
1116 | |
1117 | for (i=0; i<32; i++) { |
1118 | rsabuf[i] = session_key[i]; |
1119 | if (i < 16) |
1120 | rsabuf[i] ^= session_id[i]; |
1121 | } |
1122 | |
1123 | if (hostkey.bytes > servkey.bytes) { |
1124 | rsaencrypt(rsabuf, 32, &servkey); |
1125 | rsaencrypt(rsabuf, servkey.bytes, &hostkey); |
1126 | } else { |
1127 | rsaencrypt(rsabuf, 32, &hostkey); |
1128 | rsaencrypt(rsabuf, hostkey.bytes, &servkey); |
1129 | } |
1130 | |
c5e9c988 |
1131 | logevent("Encrypted session key"); |
1132 | |
bea1ef5f |
1133 | cipher_type = cfg.cipher == CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH : |
9697bfd2 |
1134 | cfg.cipher == CIPHER_DES ? SSH_CIPHER_DES : |
bea1ef5f |
1135 | SSH_CIPHER_3DES; |
1136 | if ((supported_ciphers_mask & (1 << cipher_type)) == 0) { |
1137 | c_write("Selected cipher not supported, falling back to 3DES\r\n", 53); |
1138 | cipher_type = SSH_CIPHER_3DES; |
1139 | } |
c5e9c988 |
1140 | switch (cipher_type) { |
1141 | case SSH_CIPHER_3DES: logevent("Using 3DES encryption"); break; |
1142 | case SSH_CIPHER_DES: logevent("Using single-DES encryption"); break; |
1143 | case SSH_CIPHER_BLOWFISH: logevent("Using Blowfish encryption"); break; |
1144 | } |
bea1ef5f |
1145 | |
e5574168 |
1146 | send_packet(SSH1_CMSG_SESSION_KEY, |
fb09bf1c |
1147 | PKT_CHAR, cipher_type, |
1148 | PKT_DATA, cookie, 8, |
1149 | PKT_CHAR, (len*8) >> 8, PKT_CHAR, (len*8) & 0xFF, |
1150 | PKT_DATA, rsabuf, len, |
1151 | PKT_INT, 0, |
1152 | PKT_END); |
1153 | |
c5e9c988 |
1154 | logevent("Trying to enable encryption..."); |
374330e2 |
1155 | |
1156 | free(rsabuf); |
1157 | |
bea1ef5f |
1158 | cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish : |
9697bfd2 |
1159 | cipher_type == SSH_CIPHER_DES ? &ssh_des : |
bea1ef5f |
1160 | &ssh_3des; |
374330e2 |
1161 | cipher->sesskey(session_key); |
1162 | |
fb09bf1c |
1163 | crWaitUntil(ispkt); |
374330e2 |
1164 | |
e5574168 |
1165 | if (pktin.type != SSH1_SMSG_SUCCESS) |
374330e2 |
1166 | fatalbox("Encryption not successfully enabled"); |
1167 | |
c5e9c988 |
1168 | logevent("Successfully started encryption"); |
1169 | |
374330e2 |
1170 | fflush(stdout); |
1171 | { |
1172 | static char username[100]; |
1173 | static int pos = 0; |
1174 | static char c; |
5c58ad2d |
1175 | if ((flags & FLAG_CONNECTION) && !*cfg.username) { |
374330e2 |
1176 | c_write("login as: ", 10); |
1177 | while (pos >= 0) { |
fb09bf1c |
1178 | crWaitUntil(!ispkt); |
374330e2 |
1179 | while (inlen--) switch (c = *in++) { |
1180 | case 10: case 13: |
1181 | username[pos] = 0; |
1182 | pos = -1; |
1183 | break; |
1184 | case 8: case 127: |
1185 | if (pos > 0) { |
1186 | c_write("\b \b", 3); |
1187 | pos--; |
1188 | } |
1189 | break; |
1190 | case 21: case 27: |
1191 | while (pos > 0) { |
1192 | c_write("\b \b", 3); |
1193 | pos--; |
1194 | } |
1195 | break; |
1196 | case 3: case 4: |
1197 | random_save_seed(); |
1198 | exit(0); |
1199 | break; |
1200 | default: |
40d24aa6 |
1201 | if (((c >= ' ' && c <= '~') || |
1202 | ((unsigned char)c >= 160)) && pos < 40) { |
374330e2 |
1203 | username[pos++] = c; |
1204 | c_write(&c, 1); |
1205 | } |
1206 | break; |
1207 | } |
1208 | } |
1209 | c_write("\r\n", 2); |
1210 | username[strcspn(username, "\n\r")] = '\0'; |
1211 | } else { |
1212 | char stuff[200]; |
1213 | strncpy(username, cfg.username, 99); |
1214 | username[99] = '\0'; |
4017be6d |
1215 | if (flags & FLAG_VERBOSE) { |
fb09bf1c |
1216 | sprintf(stuff, "Sent username \"%s\".\r\n", username); |
4017be6d |
1217 | c_write(stuff, strlen(stuff)); |
fb09bf1c |
1218 | } |
374330e2 |
1219 | } |
fb09bf1c |
1220 | |
e5574168 |
1221 | send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END); |
c5e9c988 |
1222 | { |
1223 | char userlog[20+sizeof(username)]; |
1224 | sprintf(userlog, "Sent username \"%s\"", username); |
1225 | logevent(userlog); |
1226 | } |
374330e2 |
1227 | } |
1228 | |
fb09bf1c |
1229 | crWaitUntil(ispkt); |
374330e2 |
1230 | |
7cca0d81 |
1231 | tried_publickey = 0; |
1232 | |
e5574168 |
1233 | while (pktin.type == SSH1_SMSG_FAILURE) { |
374330e2 |
1234 | static char password[100]; |
1235 | static int pos; |
1236 | static char c; |
ccbfb941 |
1237 | static int pwpkt_type; |
ccbfb941 |
1238 | /* |
1239 | * Show password prompt, having first obtained it via a TIS |
18515c51 |
1240 | * or CryptoCard exchange if we're doing TIS or CryptoCard |
1241 | * authentication. |
ccbfb941 |
1242 | */ |
e5574168 |
1243 | pwpkt_type = SSH1_CMSG_AUTH_PASSWORD; |
5c58ad2d |
1244 | if (agent_exists()) { |
1245 | /* |
1246 | * Attempt RSA authentication using Pageant. |
1247 | */ |
1248 | static unsigned char request[5], *response, *p; |
1249 | static int responselen; |
1250 | static int i, nkeys; |
1251 | static int authed = FALSE; |
1252 | void *r; |
1253 | |
1254 | logevent("Pageant is running. Requesting keys."); |
1255 | |
1256 | /* Request the keys held by the agent. */ |
1257 | PUT_32BIT(request, 1); |
1258 | request[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES; |
1259 | agent_query(request, 5, &r, &responselen); |
1260 | response = (unsigned char *)r; |
1261 | if (response) { |
1262 | p = response + 5; |
1263 | nkeys = GET_32BIT(p); p += 4; |
1264 | { char buf[64]; sprintf(buf, "Pageant has %d keys", nkeys); |
1265 | logevent(buf); } |
1266 | for (i = 0; i < nkeys; i++) { |
1267 | static struct RSAKey key; |
1268 | static Bignum challenge; |
b8bb811a |
1269 | static char *commentp; |
1270 | static int commentlen; |
5c58ad2d |
1271 | |
1272 | { char buf[64]; sprintf(buf, "Trying Pageant key #%d", i); |
1273 | logevent(buf); } |
1274 | p += 4; |
1275 | p += ssh1_read_bignum(p, &key.exponent); |
1276 | p += ssh1_read_bignum(p, &key.modulus); |
b8bb811a |
1277 | commentlen = GET_32BIT(p); p += 4; |
1278 | commentp = p; p += commentlen; |
5c58ad2d |
1279 | send_packet(SSH1_CMSG_AUTH_RSA, |
1280 | PKT_BIGNUM, key.modulus, PKT_END); |
1281 | crWaitUntil(ispkt); |
1282 | if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) { |
1283 | logevent("Key refused"); |
1284 | continue; |
1285 | } |
1286 | logevent("Received RSA challenge"); |
1287 | ssh1_read_bignum(pktin.body, &challenge); |
1288 | { |
1289 | char *agentreq, *q, *ret; |
1290 | int len, retlen; |
1291 | len = 1 + 4; /* message type, bit count */ |
1292 | len += ssh1_bignum_length(key.exponent); |
1293 | len += ssh1_bignum_length(key.modulus); |
1294 | len += ssh1_bignum_length(challenge); |
1295 | len += 16; /* session id */ |
1296 | len += 4; /* response format */ |
1297 | agentreq = malloc(4 + len); |
1298 | PUT_32BIT(agentreq, len); |
1299 | q = agentreq + 4; |
1300 | *q++ = SSH_AGENTC_RSA_CHALLENGE; |
1301 | PUT_32BIT(q, ssh1_bignum_bitcount(key.modulus)); |
1302 | q += 4; |
1303 | q += ssh1_write_bignum(q, key.exponent); |
1304 | q += ssh1_write_bignum(q, key.modulus); |
1305 | q += ssh1_write_bignum(q, challenge); |
1306 | memcpy(q, session_id, 16); q += 16; |
1307 | PUT_32BIT(q, 1); /* response format */ |
1308 | agent_query(agentreq, len+4, &ret, &retlen); |
1309 | free(agentreq); |
1310 | if (ret) { |
1311 | if (ret[4] == SSH_AGENT_RSA_RESPONSE) { |
1312 | logevent("Sending Pageant's response"); |
1313 | send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE, |
1314 | PKT_DATA, ret+5, 16, PKT_END); |
1315 | free(ret); |
1316 | crWaitUntil(ispkt); |
1317 | if (pktin.type == SSH1_SMSG_SUCCESS) { |
1318 | logevent("Pageant's response accepted"); |
b8bb811a |
1319 | c_write("Authenticated using RSA key \"", |
1320 | 29); |
1321 | c_write(commentp, commentlen); |
1322 | c_write("\" from agent\r\n", 14); |
5c58ad2d |
1323 | authed = TRUE; |
1324 | } else |
1325 | logevent("Pageant's response not accepted"); |
1326 | } else { |
1327 | logevent("Pageant failed to answer challenge"); |
1328 | free(ret); |
1329 | } |
1330 | } else { |
1331 | logevent("No reply received from Pageant"); |
1332 | } |
1333 | } |
1334 | freebn(key.exponent); |
1335 | freebn(key.modulus); |
1336 | freebn(challenge); |
1337 | if (authed) |
1338 | break; |
1339 | } |
1340 | } |
1341 | if (authed) |
1342 | break; |
1343 | } |
7cca0d81 |
1344 | if (*cfg.keyfile && !tried_publickey) |
1345 | pwpkt_type = SSH1_CMSG_AUTH_RSA; |
fb09bf1c |
1346 | |
4017be6d |
1347 | if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD && !FLAG_WINDOWED) { |
fb09bf1c |
1348 | char prompt[200]; |
1349 | sprintf(prompt, "%s@%s's password: ", cfg.username, savedhost); |
85ee8208 |
1350 | if (!ssh_get_password(prompt, password, sizeof(password))) { |
1351 | /* |
1352 | * get_password failed to get a password (for |
1353 | * example because one was supplied on the command |
1354 | * line which has already failed to work). |
1355 | * Terminate. |
1356 | */ |
1357 | logevent("No more passwords to try"); |
1358 | ssh_state = SSH_STATE_CLOSED; |
1359 | crReturn(1); |
1360 | } |
fb09bf1c |
1361 | } else { |
1362 | |
7cca0d81 |
1363 | if (pktin.type == SSH1_SMSG_FAILURE && |
1364 | cfg.try_tis_auth && |
1365 | (supported_auths_mask & (1<<SSH1_AUTH_TIS))) { |
1366 | pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE; |
1367 | logevent("Requested TIS authentication"); |
1368 | send_packet(SSH1_CMSG_AUTH_TIS, PKT_END); |
1369 | crWaitUntil(ispkt); |
1370 | if (pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) { |
1371 | logevent("TIS authentication declined"); |
1372 | c_write("TIS authentication refused.\r\n", 29); |
1373 | } else { |
1374 | int challengelen = ((pktin.body[0] << 24) | |
1375 | (pktin.body[1] << 16) | |
1376 | (pktin.body[2] << 8) | |
1377 | (pktin.body[3])); |
1378 | logevent("Received TIS challenge"); |
1379 | c_write(pktin.body+4, challengelen); |
1380 | } |
1381 | } |
18515c51 |
1382 | if (pktin.type == SSH1_SMSG_FAILURE && |
1383 | cfg.try_tis_auth && |
1384 | (supported_auths_mask & (1<<SSH1_AUTH_CCARD))) { |
1385 | pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE; |
1386 | logevent("Requested CryptoCard authentication"); |
1387 | send_packet(SSH1_CMSG_AUTH_CCARD, PKT_END); |
1388 | crWaitUntil(ispkt); |
1389 | if (pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) { |
1390 | logevent("CryptoCard authentication declined"); |
1391 | c_write("CryptoCard authentication refused.\r\n", 29); |
1392 | } else { |
1393 | int challengelen = ((pktin.body[0] << 24) | |
1394 | (pktin.body[1] << 16) | |
1395 | (pktin.body[2] << 8) | |
1396 | (pktin.body[3])); |
1397 | logevent("Received CryptoCard challenge"); |
1398 | c_write(pktin.body+4, challengelen); |
1399 | c_write("\r\nResponse : ", 13); |
1400 | } |
1401 | } |
7cca0d81 |
1402 | if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) |
1403 | c_write("password: ", 10); |
1404 | if (pwpkt_type == SSH1_CMSG_AUTH_RSA) { |
4017be6d |
1405 | if (flags & FLAG_VERBOSE) |
1406 | c_write("Trying public key authentication.\r\n", 35); |
7cca0d81 |
1407 | if (!rsakey_encrypted(cfg.keyfile)) { |
4017be6d |
1408 | if (flags & FLAG_VERBOSE) |
1409 | c_write("No passphrase required.\r\n", 25); |
7cca0d81 |
1410 | goto tryauth; |
1411 | } |
1412 | c_write("passphrase: ", 12); |
ccbfb941 |
1413 | } |
ccbfb941 |
1414 | |
7cca0d81 |
1415 | pos = 0; |
1416 | while (pos >= 0) { |
1417 | crWaitUntil(!ispkt); |
1418 | while (inlen--) switch (c = *in++) { |
1419 | case 10: case 13: |
1420 | password[pos] = 0; |
1421 | pos = -1; |
1422 | break; |
1423 | case 8: case 127: |
1424 | if (pos > 0) |
1425 | pos--; |
1426 | break; |
1427 | case 21: case 27: |
1428 | pos = 0; |
1429 | break; |
1430 | case 3: case 4: |
1431 | random_save_seed(); |
1432 | exit(0); |
1433 | break; |
1434 | default: |
1435 | if (((c >= ' ' && c <= '~') || |
1436 | ((unsigned char)c >= 160)) && pos < sizeof(password)) |
1437 | password[pos++] = c; |
1438 | break; |
1439 | } |
1440 | } |
1441 | c_write("\r\n", 2); |
fb09bf1c |
1442 | |
1443 | } |
1444 | |
7cca0d81 |
1445 | tryauth: |
1446 | if (pwpkt_type == SSH1_CMSG_AUTH_RSA) { |
1447 | /* |
1448 | * Try public key authentication with the specified |
1449 | * key file. |
1450 | */ |
1451 | static struct RSAKey pubkey; |
1452 | static Bignum challenge, response; |
1453 | static int i; |
1454 | static unsigned char buffer[32]; |
1455 | |
1456 | tried_publickey = 1; |
1457 | i = loadrsakey(cfg.keyfile, &pubkey, password); |
1458 | if (i == 0) { |
1459 | c_write("Couldn't load public key from ", 30); |
1460 | c_write(cfg.keyfile, strlen(cfg.keyfile)); |
1461 | c_write(".\r\n", 3); |
1462 | continue; /* go and try password */ |
1463 | } |
1464 | if (i == -1) { |
1465 | c_write("Wrong passphrase.\r\n", 19); |
1466 | tried_publickey = 0; |
1467 | continue; /* try again */ |
1468 | } |
1469 | |
1470 | /* |
1471 | * Send a public key attempt. |
1472 | */ |
1473 | send_packet(SSH1_CMSG_AUTH_RSA, |
1474 | PKT_BIGNUM, pubkey.modulus, PKT_END); |
1475 | |
1476 | crWaitUntil(ispkt); |
1477 | if (pktin.type == SSH1_SMSG_FAILURE) { |
4017be6d |
1478 | if (flags & FLAG_VERBOSE) |
1479 | c_write("Server refused our public key.\r\n", 32); |
7cca0d81 |
1480 | continue; /* go and try password */ |
1481 | } |
1482 | if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) |
1483 | fatalbox("Bizarre response to offer of public key"); |
1484 | ssh1_read_bignum(pktin.body, &challenge); |
1485 | response = rsadecrypt(challenge, &pubkey); |
1486 | freebn(pubkey.private_exponent); /* burn the evidence */ |
1487 | |
1488 | for (i = 0; i < 32; i += 2) { |
1489 | buffer[i] = response[16-i/2] >> 8; |
1490 | buffer[i+1] = response[16-i/2] & 0xFF; |
1491 | } |
1492 | |
1493 | MD5Init(&md5c); |
1494 | MD5Update(&md5c, buffer, 32); |
1495 | MD5Update(&md5c, session_id, 16); |
1496 | MD5Final(buffer, &md5c); |
1497 | |
1498 | send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE, |
1499 | PKT_DATA, buffer, 16, PKT_END); |
1500 | |
1501 | crWaitUntil(ispkt); |
1502 | if (pktin.type == SSH1_SMSG_FAILURE) { |
4017be6d |
1503 | if (flags & FLAG_VERBOSE) |
1504 | c_write("Failed to authenticate with our public key.\r\n", |
1505 | 45); |
7cca0d81 |
1506 | continue; /* go and try password */ |
1507 | } else if (pktin.type != SSH1_SMSG_SUCCESS) { |
1508 | fatalbox("Bizarre response to RSA authentication response"); |
1509 | } |
1510 | |
1511 | break; /* we're through! */ |
1512 | } else { |
1513 | send_packet(pwpkt_type, PKT_STR, password, PKT_END); |
1514 | } |
c5e9c988 |
1515 | logevent("Sent password"); |
374330e2 |
1516 | memset(password, 0, strlen(password)); |
fb09bf1c |
1517 | crWaitUntil(ispkt); |
e5574168 |
1518 | if (pktin.type == SSH1_SMSG_FAILURE) { |
4017be6d |
1519 | if (flags & FLAG_VERBOSE) |
1520 | c_write("Access denied\r\n", 15); |
c5e9c988 |
1521 | logevent("Authentication refused"); |
e5574168 |
1522 | } else if (pktin.type == SSH1_MSG_DISCONNECT) { |
fb09bf1c |
1523 | logevent("Received disconnect request"); |
85ee8208 |
1524 | ssh_state = SSH_STATE_CLOSED; |
1525 | crReturn(1); |
e5574168 |
1526 | } else if (pktin.type != SSH1_SMSG_SUCCESS) { |
374330e2 |
1527 | fatalbox("Strange packet received, type %d", pktin.type); |
1528 | } |
1529 | } |
1530 | |
c5e9c988 |
1531 | logevent("Authentication successful"); |
1532 | |
fb09bf1c |
1533 | crFinish(1); |
1534 | } |
1535 | |
e5574168 |
1536 | static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) { |
fb09bf1c |
1537 | crBegin; |
1538 | |
1539 | random_init(); |
1540 | |
e5574168 |
1541 | while (!do_ssh1_login(in, inlen, ispkt)) { |
fb09bf1c |
1542 | crReturnV; |
85ee8208 |
1543 | } |
1544 | if (ssh_state == SSH_STATE_CLOSED) |
1545 | crReturnV; |
fb09bf1c |
1546 | |
979310f1 |
1547 | if (cfg.agentfwd && agent_exists()) { |
dacbd0e8 |
1548 | logevent("Requesting agent forwarding"); |
1549 | send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END); |
1550 | do { crReturnV; } while (!ispkt); |
1551 | if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) { |
1552 | fatalbox("Protocol confusion"); |
1553 | } else if (pktin.type == SSH1_SMSG_FAILURE) { |
1554 | logevent("Agent forwarding refused"); |
1555 | } else |
1556 | logevent("Agent forwarding enabled"); |
1557 | } |
1558 | |
fef97f43 |
1559 | if (!cfg.nopty) { |
e5574168 |
1560 | send_packet(SSH1_CMSG_REQUEST_PTY, |
fb09bf1c |
1561 | PKT_STR, cfg.termtype, |
1562 | PKT_INT, rows, PKT_INT, cols, |
1563 | PKT_INT, 0, PKT_INT, 0, |
1564 | PKT_CHAR, 0, |
1565 | PKT_END); |
fef97f43 |
1566 | ssh_state = SSH_STATE_INTERMED; |
1567 | do { crReturnV; } while (!ispkt); |
e5574168 |
1568 | if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) { |
fef97f43 |
1569 | fatalbox("Protocol confusion"); |
e5574168 |
1570 | } else if (pktin.type == SSH1_SMSG_FAILURE) { |
fef97f43 |
1571 | c_write("Server refused to allocate pty\r\n", 32); |
1572 | } |
c5e9c988 |
1573 | logevent("Allocated pty"); |
374330e2 |
1574 | } |
1575 | |
6abbf9e3 |
1576 | if (*cfg.remote_cmd) |
1577 | send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cfg.remote_cmd, PKT_END); |
1578 | else |
1579 | send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END); |
c5e9c988 |
1580 | logevent("Started session"); |
374330e2 |
1581 | |
1582 | ssh_state = SSH_STATE_SESSION; |
1583 | if (size_needed) |
1584 | ssh_size(); |
1585 | |
8ccc75b0 |
1586 | ssh_send_ok = 1; |
dacbd0e8 |
1587 | ssh_channels = newtree234(ssh_channelcmp); |
374330e2 |
1588 | while (1) { |
1589 | crReturnV; |
1590 | if (ispkt) { |
e5574168 |
1591 | if (pktin.type == SSH1_SMSG_STDOUT_DATA || |
1592 | pktin.type == SSH1_SMSG_STDERR_DATA) { |
fb09bf1c |
1593 | long len = GET_32BIT(pktin.body); |
1594 | c_write(pktin.body+4, len); |
e5574168 |
1595 | } else if (pktin.type == SSH1_MSG_DISCONNECT) { |
21248260 |
1596 | ssh_state = SSH_STATE_CLOSED; |
c5e9c988 |
1597 | logevent("Received disconnect request"); |
dacbd0e8 |
1598 | } else if (pktin.type == SSH1_SMSG_AGENT_OPEN) { |
1599 | /* Remote side is trying to open a channel to talk to our |
1600 | * agent. Give them back a local channel number. */ |
1601 | int i = 1; |
1602 | struct ssh_channel *c; |
1603 | enum234 e; |
1604 | for (c = first234(ssh_channels, &e); c; c = next234(&e)) { |
1605 | if (c->localid > i) |
1606 | break; /* found a free number */ |
1607 | i = c->localid + 1; |
1608 | } |
1609 | c = malloc(sizeof(struct ssh_channel)); |
1610 | c->remoteid = GET_32BIT(pktin.body); |
1611 | c->localid = i; |
b8bb811a |
1612 | c->closes = 0; |
dacbd0e8 |
1613 | c->type = SSH1_SMSG_AGENT_OPEN; /* identify channel type */ |
1614 | add234(ssh_channels, c); |
1615 | send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION, |
1616 | PKT_INT, c->remoteid, PKT_INT, c->localid, |
1617 | PKT_END); |
1618 | } else if (pktin.type == SSH1_MSG_CHANNEL_CLOSE || |
1619 | pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) { |
1620 | /* Remote side closes a channel. */ |
1621 | int i = GET_32BIT(pktin.body); |
1622 | struct ssh_channel *c; |
1623 | c = find234(ssh_channels, &i, ssh_channelfind); |
1624 | if (c) { |
1625 | int closetype; |
1626 | closetype = (pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2); |
1627 | send_packet(pktin.type, PKT_INT, c->remoteid, PKT_END); |
1628 | c->closes |= closetype; |
1629 | if (c->closes == 3) { |
1630 | del234(ssh_channels, c); |
1631 | free(c); |
1632 | } |
1633 | } |
1634 | } else if (pktin.type == SSH1_MSG_CHANNEL_DATA) { |
1635 | /* Data sent down one of our channels. */ |
1636 | int i = GET_32BIT(pktin.body); |
1637 | int len = GET_32BIT(pktin.body+4); |
1638 | unsigned char *p = pktin.body+8; |
1639 | struct ssh_channel *c; |
1640 | c = find234(ssh_channels, &i, ssh_channelfind); |
1641 | if (c) { |
1642 | switch(c->type) { |
1643 | case SSH1_SMSG_AGENT_OPEN: |
1644 | /* Data for an agent message. Buffer it. */ |
1645 | while (len > 0) { |
1646 | if (c->u.a.lensofar < 4) { |
1647 | int l = min(4 - c->u.a.lensofar, len); |
1648 | memcpy(c->u.a.msglen + c->u.a.lensofar, p, l); |
1649 | p += l; len -= l; c->u.a.lensofar += l; |
1650 | } |
1651 | if (c->u.a.lensofar == 4) { |
1652 | c->u.a.totallen = 4 + GET_32BIT(c->u.a.msglen); |
1653 | c->u.a.message = malloc(c->u.a.totallen); |
1654 | memcpy(c->u.a.message, c->u.a.msglen, 4); |
1655 | } |
1656 | if (c->u.a.lensofar >= 4 && len > 0) { |
1657 | int l = min(c->u.a.totallen - c->u.a.lensofar, len); |
1658 | memcpy(c->u.a.message + c->u.a.lensofar, p, l); |
1659 | p += l; len -= l; c->u.a.lensofar += l; |
1660 | } |
1661 | if (c->u.a.lensofar == c->u.a.totallen) { |
1662 | void *reply, *sentreply; |
1663 | int replylen; |
1664 | agent_query(c->u.a.message, c->u.a.totallen, |
1665 | &reply, &replylen); |
1666 | if (reply) |
1667 | sentreply = reply; |
1668 | else { |
1669 | /* Fake SSH_AGENT_FAILURE. */ |
1670 | sentreply = "\0\0\0\1\5"; |
1671 | replylen = 5; |
1672 | } |
1673 | send_packet(SSH1_MSG_CHANNEL_DATA, |
1674 | PKT_INT, c->remoteid, |
1675 | PKT_INT, replylen, |
1676 | PKT_DATA, sentreply, replylen, |
1677 | PKT_END); |
1678 | if (reply) |
1679 | free(reply); |
1680 | free(c->u.a.message); |
1681 | c->u.a.lensofar = 0; |
1682 | } |
1683 | } |
1684 | break; |
1685 | } |
1686 | } |
e5574168 |
1687 | } else if (pktin.type == SSH1_SMSG_SUCCESS) { |
972a41c8 |
1688 | /* may be from EXEC_SHELL on some servers */ |
e5574168 |
1689 | } else if (pktin.type == SSH1_SMSG_FAILURE) { |
972a41c8 |
1690 | /* may be from EXEC_SHELL on some servers |
374330e2 |
1691 | * if no pty is available or in other odd cases. Ignore */ |
e5574168 |
1692 | } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) { |
1693 | send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END); |
374330e2 |
1694 | } else { |
1695 | fatalbox("Strange packet received: type %d", pktin.type); |
1696 | } |
1697 | } else { |
e5574168 |
1698 | send_packet(SSH1_CMSG_STDIN_DATA, |
fb09bf1c |
1699 | PKT_INT, inlen, PKT_DATA, in, inlen, PKT_END); |
374330e2 |
1700 | } |
1701 | } |
1702 | |
1703 | crFinishV; |
1704 | } |
1705 | |
1706 | /* |
e5574168 |
1707 | * Utility routine for decoding comma-separated strings in KEXINIT. |
1708 | */ |
1709 | int in_commasep_string(char *needle, char *haystack, int haylen) { |
1710 | int needlen = strlen(needle); |
1711 | while (1) { |
1712 | /* |
1713 | * Is it at the start of the string? |
1714 | */ |
1715 | if (haylen >= needlen && /* haystack is long enough */ |
1716 | !memcmp(needle, haystack, needlen) && /* initial match */ |
1717 | (haylen == needlen || haystack[needlen] == ',') |
1718 | /* either , or EOS follows */ |
1719 | ) |
1720 | return 1; |
1721 | /* |
1722 | * If not, search for the next comma and resume after that. |
1723 | * If no comma found, terminate. |
1724 | */ |
1725 | while (haylen > 0 && *haystack != ',') |
1726 | haylen--, haystack++; |
1727 | if (haylen == 0) |
1728 | return 0; |
1729 | haylen--, haystack++; /* skip over comma itself */ |
1730 | } |
1731 | } |
1732 | |
1733 | /* |
d39f364a |
1734 | * SSH2 key creation method. |
1735 | */ |
1736 | void ssh2_mkkey(Bignum K, char *H, char chr, char *keyspace) { |
1737 | SHA_State s; |
1738 | /* First 20 bytes. */ |
1739 | SHA_Init(&s); |
1740 | sha_mpint(&s, K); |
1741 | SHA_Bytes(&s, H, 20); |
1742 | SHA_Bytes(&s, &chr, 1); |
1743 | SHA_Bytes(&s, H, 20); |
1744 | SHA_Final(&s, keyspace); |
1745 | /* Next 20 bytes. */ |
1746 | SHA_Init(&s); |
1747 | sha_mpint(&s, K); |
1748 | SHA_Bytes(&s, H, 20); |
1749 | SHA_Bytes(&s, keyspace, 20); |
1750 | SHA_Final(&s, keyspace+20); |
1751 | } |
1752 | |
1753 | /* |
7cca0d81 |
1754 | * Handle the SSH2 transport layer. |
e5574168 |
1755 | */ |
7cca0d81 |
1756 | static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt) |
e5574168 |
1757 | { |
1758 | static int i, len; |
1759 | static char *str; |
1760 | static Bignum e, f, K; |
1761 | static struct ssh_cipher *cscipher_tobe = NULL; |
1762 | static struct ssh_cipher *sccipher_tobe = NULL; |
1763 | static struct ssh_mac *csmac_tobe = NULL; |
1764 | static struct ssh_mac *scmac_tobe = NULL; |
1765 | static struct ssh_compress *cscomp_tobe = NULL; |
1766 | static struct ssh_compress *sccomp_tobe = NULL; |
7cca0d81 |
1767 | static char *hostkeydata, *sigdata, *keystr; |
e5574168 |
1768 | static int hostkeylen, siglen; |
1769 | static unsigned char exchange_hash[20]; |
d39f364a |
1770 | static unsigned char keyspace[40]; |
e5574168 |
1771 | |
1772 | crBegin; |
7cca0d81 |
1773 | random_init(); |
e5574168 |
1774 | |
7cca0d81 |
1775 | begin_key_exchange: |
e5574168 |
1776 | /* |
1777 | * Construct and send our key exchange packet. |
1778 | */ |
1779 | ssh2_pkt_init(SSH2_MSG_KEXINIT); |
1780 | for (i = 0; i < 16; i++) |
1781 | ssh2_pkt_addbyte((unsigned char)random_byte()); |
1782 | /* List key exchange algorithms. */ |
1783 | ssh2_pkt_addstring_start(); |
1784 | for (i = 0; i < lenof(kex_algs); i++) { |
1785 | ssh2_pkt_addstring_str(kex_algs[i]->name); |
1786 | if (i < lenof(kex_algs)-1) |
1787 | ssh2_pkt_addstring_str(","); |
1788 | } |
1789 | /* List server host key algorithms. */ |
1790 | ssh2_pkt_addstring_start(); |
1791 | for (i = 0; i < lenof(hostkey_algs); i++) { |
1792 | ssh2_pkt_addstring_str(hostkey_algs[i]->name); |
1793 | if (i < lenof(hostkey_algs)-1) |
1794 | ssh2_pkt_addstring_str(","); |
1795 | } |
1796 | /* List client->server encryption algorithms. */ |
1797 | ssh2_pkt_addstring_start(); |
1798 | for (i = 0; i < lenof(ciphers); i++) { |
1799 | ssh2_pkt_addstring_str(ciphers[i]->name); |
1800 | if (i < lenof(ciphers)-1) |
1801 | ssh2_pkt_addstring_str(","); |
1802 | } |
1803 | /* List server->client encryption algorithms. */ |
1804 | ssh2_pkt_addstring_start(); |
1805 | for (i = 0; i < lenof(ciphers); i++) { |
1806 | ssh2_pkt_addstring_str(ciphers[i]->name); |
1807 | if (i < lenof(ciphers)-1) |
1808 | ssh2_pkt_addstring_str(","); |
1809 | } |
1810 | /* List client->server MAC algorithms. */ |
1811 | ssh2_pkt_addstring_start(); |
1812 | for (i = 0; i < lenof(macs); i++) { |
1813 | ssh2_pkt_addstring_str(macs[i]->name); |
1814 | if (i < lenof(macs)-1) |
1815 | ssh2_pkt_addstring_str(","); |
1816 | } |
1817 | /* List server->client MAC algorithms. */ |
1818 | ssh2_pkt_addstring_start(); |
1819 | for (i = 0; i < lenof(macs); i++) { |
1820 | ssh2_pkt_addstring_str(macs[i]->name); |
1821 | if (i < lenof(macs)-1) |
1822 | ssh2_pkt_addstring_str(","); |
1823 | } |
1824 | /* List client->server compression algorithms. */ |
1825 | ssh2_pkt_addstring_start(); |
1826 | for (i = 0; i < lenof(compressions); i++) { |
1827 | ssh2_pkt_addstring_str(compressions[i]->name); |
1828 | if (i < lenof(compressions)-1) |
1829 | ssh2_pkt_addstring_str(","); |
1830 | } |
1831 | /* List server->client compression algorithms. */ |
1832 | ssh2_pkt_addstring_start(); |
1833 | for (i = 0; i < lenof(compressions); i++) { |
1834 | ssh2_pkt_addstring_str(compressions[i]->name); |
1835 | if (i < lenof(compressions)-1) |
1836 | ssh2_pkt_addstring_str(","); |
1837 | } |
1838 | /* List client->server languages. Empty list. */ |
1839 | ssh2_pkt_addstring_start(); |
1840 | /* List server->client languages. Empty list. */ |
1841 | ssh2_pkt_addstring_start(); |
1842 | /* First KEX packet does _not_ follow, because we're not that brave. */ |
1843 | ssh2_pkt_addbool(FALSE); |
1844 | /* Reserved. */ |
1845 | ssh2_pkt_adduint32(0); |
1846 | sha_string(&exhash, pktout.data+5, pktout.length-5); |
1847 | ssh2_pkt_send(); |
1848 | |
1849 | if (!ispkt) crWaitUntil(ispkt); |
1850 | sha_string(&exhash, pktin.data+5, pktin.length-5); |
1851 | |
1852 | /* |
1853 | * Now examine the other side's KEXINIT to see what we're up |
1854 | * to. |
1855 | */ |
7cca0d81 |
1856 | if (pktin.type != SSH2_MSG_KEXINIT) { |
e5574168 |
1857 | fatalbox("expected key exchange packet from server"); |
7cca0d81 |
1858 | } |
e5574168 |
1859 | kex = NULL; hostkey = NULL; cscipher_tobe = NULL; sccipher_tobe = NULL; |
1860 | csmac_tobe = NULL; scmac_tobe = NULL; cscomp_tobe = NULL; sccomp_tobe = NULL; |
1861 | pktin.savedpos += 16; /* skip garbage cookie */ |
1862 | ssh2_pkt_getstring(&str, &len); /* key exchange algorithms */ |
1863 | for (i = 0; i < lenof(kex_algs); i++) { |
1864 | if (in_commasep_string(kex_algs[i]->name, str, len)) { |
1865 | kex = kex_algs[i]; |
1866 | break; |
1867 | } |
1868 | } |
1869 | ssh2_pkt_getstring(&str, &len); /* host key algorithms */ |
1870 | for (i = 0; i < lenof(hostkey_algs); i++) { |
1871 | if (in_commasep_string(hostkey_algs[i]->name, str, len)) { |
1872 | hostkey = hostkey_algs[i]; |
1873 | break; |
1874 | } |
1875 | } |
1876 | ssh2_pkt_getstring(&str, &len); /* client->server cipher */ |
1877 | for (i = 0; i < lenof(ciphers); i++) { |
1878 | if (in_commasep_string(ciphers[i]->name, str, len)) { |
1879 | cscipher_tobe = ciphers[i]; |
1880 | break; |
1881 | } |
1882 | } |
1883 | ssh2_pkt_getstring(&str, &len); /* server->client cipher */ |
1884 | for (i = 0; i < lenof(ciphers); i++) { |
1885 | if (in_commasep_string(ciphers[i]->name, str, len)) { |
1886 | sccipher_tobe = ciphers[i]; |
1887 | break; |
1888 | } |
1889 | } |
1890 | ssh2_pkt_getstring(&str, &len); /* client->server mac */ |
1891 | for (i = 0; i < lenof(macs); i++) { |
1892 | if (in_commasep_string(macs[i]->name, str, len)) { |
1893 | csmac_tobe = macs[i]; |
1894 | break; |
1895 | } |
1896 | } |
1897 | ssh2_pkt_getstring(&str, &len); /* server->client mac */ |
1898 | for (i = 0; i < lenof(macs); i++) { |
1899 | if (in_commasep_string(macs[i]->name, str, len)) { |
1900 | scmac_tobe = macs[i]; |
1901 | break; |
1902 | } |
1903 | } |
1904 | ssh2_pkt_getstring(&str, &len); /* client->server compression */ |
1905 | for (i = 0; i < lenof(compressions); i++) { |
1906 | if (in_commasep_string(compressions[i]->name, str, len)) { |
1907 | cscomp_tobe = compressions[i]; |
1908 | break; |
1909 | } |
1910 | } |
1911 | ssh2_pkt_getstring(&str, &len); /* server->client compression */ |
1912 | for (i = 0; i < lenof(compressions); i++) { |
1913 | if (in_commasep_string(compressions[i]->name, str, len)) { |
1914 | sccomp_tobe = compressions[i]; |
1915 | break; |
1916 | } |
1917 | } |
e5574168 |
1918 | |
1919 | /* |
1920 | * Currently we only support Diffie-Hellman and DSS, so let's |
1921 | * bomb out if those aren't selected. |
1922 | */ |
1923 | if (kex != &ssh_diffiehellman || hostkey != &ssh_dss) |
1924 | fatalbox("internal fault: chaos in SSH 2 transport layer"); |
1925 | |
1926 | /* |
1927 | * Now we begin the fun. Generate and send e for Diffie-Hellman. |
1928 | */ |
1929 | e = dh_create_e(); |
e5574168 |
1930 | ssh2_pkt_init(SSH2_MSG_KEXDH_INIT); |
1931 | ssh2_pkt_addmp(e); |
1932 | ssh2_pkt_send(); |
1933 | |
1934 | crWaitUntil(ispkt); |
7cca0d81 |
1935 | if (pktin.type != SSH2_MSG_KEXDH_REPLY) { |
e5574168 |
1936 | fatalbox("expected key exchange packet from server"); |
7cca0d81 |
1937 | } |
e5574168 |
1938 | ssh2_pkt_getstring(&hostkeydata, &hostkeylen); |
1939 | f = ssh2_pkt_getmp(); |
e5574168 |
1940 | ssh2_pkt_getstring(&sigdata, &siglen); |
1941 | |
1942 | K = dh_find_K(f); |
e5574168 |
1943 | |
1944 | sha_string(&exhash, hostkeydata, hostkeylen); |
1945 | sha_mpint(&exhash, e); |
1946 | sha_mpint(&exhash, f); |
1947 | sha_mpint(&exhash, K); |
1948 | SHA_Final(&exhash, exchange_hash); |
1949 | |
7cca0d81 |
1950 | #if 0 |
e5574168 |
1951 | debug(("Exchange hash is:\r\n")); |
1952 | for (i = 0; i < 20; i++) |
1953 | debug((" %02x", exchange_hash[i])); |
1954 | debug(("\r\n")); |
7cca0d81 |
1955 | #endif |
1956 | |
1957 | hostkey->setkey(hostkeydata, hostkeylen); |
1958 | if (!hostkey->verifysig(sigdata, siglen, exchange_hash, 20)) |
1959 | fatalbox("Server failed host key check"); |
e5574168 |
1960 | |
1961 | /* |
7cca0d81 |
1962 | * Expect SSH2_MSG_NEWKEYS from server. |
d39f364a |
1963 | */ |
7cca0d81 |
1964 | crWaitUntil(ispkt); |
1965 | if (pktin.type != SSH2_MSG_NEWKEYS) |
1966 | fatalbox("expected new-keys packet from server"); |
d39f364a |
1967 | |
1968 | /* |
7cca0d81 |
1969 | * Authenticate remote host: verify host key. (We've already |
1970 | * checked the signature of the exchange hash.) |
e5574168 |
1971 | */ |
7cca0d81 |
1972 | keystr = hostkey->fmtkey(); |
1973 | verify_ssh_host_key(savedhost, keystr); |
1974 | free(keystr); |
d39f364a |
1975 | |
1976 | /* |
7cca0d81 |
1977 | * Send SSH2_MSG_NEWKEYS. |
d39f364a |
1978 | */ |
1979 | ssh2_pkt_init(SSH2_MSG_NEWKEYS); |
1980 | ssh2_pkt_send(); |
d39f364a |
1981 | |
1982 | /* |
1983 | * Create and initialise session keys. |
1984 | */ |
1985 | cscipher = cscipher_tobe; |
1986 | sccipher = sccipher_tobe; |
1987 | csmac = csmac_tobe; |
1988 | scmac = scmac_tobe; |
1989 | cscomp = cscomp_tobe; |
1990 | sccomp = sccomp_tobe; |
1991 | /* |
1992 | * Set IVs after keys. |
1993 | */ |
1994 | ssh2_mkkey(K, exchange_hash, 'C', keyspace); cscipher->setcskey(keyspace); |
1995 | ssh2_mkkey(K, exchange_hash, 'D', keyspace); cscipher->setsckey(keyspace); |
1996 | ssh2_mkkey(K, exchange_hash, 'A', keyspace); cscipher->setcsiv(keyspace); |
1997 | ssh2_mkkey(K, exchange_hash, 'B', keyspace); sccipher->setsciv(keyspace); |
1998 | ssh2_mkkey(K, exchange_hash, 'E', keyspace); csmac->setcskey(keyspace); |
1999 | ssh2_mkkey(K, exchange_hash, 'F', keyspace); scmac->setsckey(keyspace); |
2000 | |
033b4cef |
2001 | /* |
7cca0d81 |
2002 | * Now we're encrypting. Begin returning 1 to the protocol main |
2003 | * function so that other things can run on top of the |
2004 | * transport. If we ever see a KEXINIT, we must go back to the |
2005 | * start. |
033b4cef |
2006 | */ |
7cca0d81 |
2007 | do { |
2008 | crReturn(1); |
2009 | } while (!(ispkt && pktin.type == SSH2_MSG_KEXINIT)); |
2010 | goto begin_key_exchange; |
e5574168 |
2011 | |
2012 | crFinish(1); |
2013 | } |
2014 | |
7cca0d81 |
2015 | /* |
6abbf9e3 |
2016 | * SSH2: remote identifier for the main session channel. |
2017 | */ |
2018 | static unsigned long ssh_remote_channel; |
2019 | |
2020 | /* |
7cca0d81 |
2021 | * Handle the SSH2 userauth and connection layers. |
2022 | */ |
2023 | static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) |
2024 | { |
7cca0d81 |
2025 | static unsigned long remote_winsize; |
2026 | static unsigned long remote_maxpkt; |
2027 | |
e5574168 |
2028 | crBegin; |
2029 | |
7cca0d81 |
2030 | /* |
2031 | * Request userauth protocol, and await a response to it. |
2032 | */ |
2033 | ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST); |
2034 | ssh2_pkt_addstring("ssh-userauth"); |
2035 | ssh2_pkt_send(); |
2036 | crWaitUntilV(ispkt); |
2037 | if (pktin.type != SSH2_MSG_SERVICE_ACCEPT) |
2038 | fatalbox("Server refused user authentication protocol"); |
2039 | |
2040 | /* |
2041 | * FIXME: currently we support only password authentication. |
2042 | * (This places us technically in violation of the SSH2 spec. |
2043 | * We must fix this.) |
2044 | */ |
2045 | while (1) { |
2046 | /* |
2047 | * Get a username and a password. |
2048 | */ |
2049 | static char username[100]; |
2050 | static char password[100]; |
2051 | static int pos = 0; |
2052 | static char c; |
e5574168 |
2053 | |
4017be6d |
2054 | if ((flags & FLAG_CONNECTION) && !*cfg.username) { |
7cca0d81 |
2055 | c_write("login as: ", 10); |
2056 | while (pos >= 0) { |
2057 | crWaitUntilV(!ispkt); |
2058 | while (inlen--) switch (c = *in++) { |
2059 | case 10: case 13: |
2060 | username[pos] = 0; |
2061 | pos = -1; |
2062 | break; |
2063 | case 8: case 127: |
2064 | if (pos > 0) { |
2065 | c_write("\b \b", 3); |
2066 | pos--; |
2067 | } |
2068 | break; |
2069 | case 21: case 27: |
2070 | while (pos > 0) { |
2071 | c_write("\b \b", 3); |
2072 | pos--; |
2073 | } |
2074 | break; |
2075 | case 3: case 4: |
2076 | random_save_seed(); |
2077 | exit(0); |
2078 | break; |
2079 | default: |
2080 | if (((c >= ' ' && c <= '~') || |
2081 | ((unsigned char)c >= 160)) && pos < 40) { |
2082 | username[pos++] = c; |
2083 | c_write(&c, 1); |
2084 | } |
2085 | break; |
2086 | } |
2087 | } |
2088 | c_write("\r\n", 2); |
2089 | username[strcspn(username, "\n\r")] = '\0'; |
2090 | } else { |
2091 | char stuff[200]; |
2092 | strncpy(username, cfg.username, 99); |
2093 | username[99] = '\0'; |
4017be6d |
2094 | if (flags & FLAG_VERBOSE) { |
7cca0d81 |
2095 | sprintf(stuff, "Using username \"%s\".\r\n", username); |
2096 | c_write(stuff, strlen(stuff)); |
2097 | } |
2098 | } |
2099 | |
4017be6d |
2100 | if (!(flags & FLAG_WINDOWED)) { |
7cca0d81 |
2101 | char prompt[200]; |
2102 | sprintf(prompt, "%s@%s's password: ", cfg.username, savedhost); |
2103 | if (!ssh_get_password(prompt, password, sizeof(password))) { |
2104 | /* |
2105 | * get_password failed to get a password (for |
2106 | * example because one was supplied on the command |
2107 | * line which has already failed to work). |
2108 | * Terminate. |
2109 | */ |
2110 | logevent("No more passwords to try"); |
2111 | ssh_state = SSH_STATE_CLOSED; |
2112 | crReturnV; |
2113 | } |
2114 | } else { |
2115 | c_write("password: ", 10); |
2116 | |
2117 | pos = 0; |
2118 | while (pos >= 0) { |
2119 | crWaitUntilV(!ispkt); |
2120 | while (inlen--) switch (c = *in++) { |
2121 | case 10: case 13: |
2122 | password[pos] = 0; |
2123 | pos = -1; |
2124 | break; |
2125 | case 8: case 127: |
2126 | if (pos > 0) |
2127 | pos--; |
2128 | break; |
2129 | case 21: case 27: |
2130 | pos = 0; |
2131 | break; |
2132 | case 3: case 4: |
2133 | random_save_seed(); |
2134 | exit(0); |
2135 | break; |
2136 | default: |
2137 | if (((c >= ' ' && c <= '~') || |
2138 | ((unsigned char)c >= 160)) && pos < 40) |
2139 | password[pos++] = c; |
2140 | break; |
2141 | } |
2142 | } |
2143 | c_write("\r\n", 2); |
2144 | } |
2145 | |
2146 | ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST); |
2147 | ssh2_pkt_addstring(username); |
2148 | ssh2_pkt_addstring("ssh-connection"); /* service requested */ |
2149 | ssh2_pkt_addstring("password"); |
2150 | ssh2_pkt_addbool(FALSE); |
2151 | ssh2_pkt_addstring(password); |
2152 | ssh2_pkt_send(); |
2153 | |
2154 | crWaitUntilV(ispkt); |
2155 | if (pktin.type != SSH2_MSG_USERAUTH_SUCCESS) { |
2156 | c_write("Access denied\r\n", 15); |
2157 | logevent("Authentication refused"); |
2158 | } else |
2159 | break; |
2160 | } |
2161 | |
2162 | /* |
2163 | * Now we're authenticated for the connection protocol. The |
2164 | * connection protocol will automatically have started at this |
2165 | * point; there's no need to send SERVICE_REQUEST. |
2166 | */ |
2167 | |
2168 | /* |
2169 | * So now create a channel with a session in it. |
2170 | */ |
2171 | ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN); |
2172 | ssh2_pkt_addstring("session"); |
2173 | ssh2_pkt_adduint32(100); /* as good as any */ |
59dcd2a8 |
2174 | ssh2_pkt_adduint32(0x7FFFFFFFUL); /* very big window which we ignore */ |
2175 | ssh2_pkt_adduint32(0x7FFFFFFFUL); /* very big max pkt size */ |
7cca0d81 |
2176 | ssh2_pkt_send(); |
2177 | crWaitUntilV(ispkt); |
2178 | if (pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) { |
2179 | fatalbox("Server refused to open a session"); |
2180 | /* FIXME: error data comes back in FAILURE packet */ |
2181 | } |
2182 | if (ssh2_pkt_getuint32() != 100) { |
2183 | fatalbox("Server's channel confirmation cited wrong channel"); |
2184 | } |
6abbf9e3 |
2185 | ssh_remote_channel = ssh2_pkt_getuint32(); |
7cca0d81 |
2186 | remote_winsize = ssh2_pkt_getuint32(); |
2187 | remote_maxpkt = ssh2_pkt_getuint32(); |
2188 | logevent("Opened channel for session"); |
2189 | |
2190 | /* |
2191 | * Now allocate a pty for the session. |
2192 | */ |
2193 | ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST); |
6abbf9e3 |
2194 | ssh2_pkt_adduint32(ssh_remote_channel); /* recipient channel */ |
7cca0d81 |
2195 | ssh2_pkt_addstring("pty-req"); |
2196 | ssh2_pkt_addbool(1); /* want reply */ |
2197 | ssh2_pkt_addstring(cfg.termtype); |
2198 | ssh2_pkt_adduint32(cols); |
2199 | ssh2_pkt_adduint32(rows); |
2200 | ssh2_pkt_adduint32(0); /* pixel width */ |
2201 | ssh2_pkt_adduint32(0); /* pixel height */ |
2202 | ssh2_pkt_addstring_start(); |
2203 | ssh2_pkt_addstring_data("\0", 1); /* TTY_OP_END, no special options */ |
2204 | ssh2_pkt_send(); |
2205 | |
2206 | do { /* FIXME: pay attention to these */ |
2207 | crWaitUntilV(ispkt); |
2208 | } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST); |
2209 | |
2210 | if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) { |
2211 | if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) { |
2212 | fatalbox("Server got confused by pty request"); |
2213 | } |
2214 | c_write("Server refused to allocate pty\r\n", 32); |
2215 | } else { |
2216 | logevent("Allocated pty"); |
2217 | } |
2218 | |
2219 | /* |
2220 | * Start a shell. |
2221 | */ |
2222 | ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST); |
6abbf9e3 |
2223 | ssh2_pkt_adduint32(ssh_remote_channel); /* recipient channel */ |
7cca0d81 |
2224 | ssh2_pkt_addstring("shell"); |
2225 | ssh2_pkt_addbool(1); /* want reply */ |
2226 | ssh2_pkt_send(); |
2227 | do { /* FIXME: pay attention to these */ |
2228 | crWaitUntilV(ispkt); |
2229 | } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST); |
2230 | if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) { |
2231 | if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) { |
2232 | fatalbox("Server got confused by shell request"); |
2233 | } |
2234 | fatalbox("Server refused to start a shell"); |
2235 | } else { |
2236 | logevent("Started a shell"); |
2237 | } |
2238 | |
2239 | /* |
2240 | * Transfer data! |
2241 | */ |
8ccc75b0 |
2242 | ssh_send_ok = 1; |
7cca0d81 |
2243 | while (1) { |
e5574168 |
2244 | crReturnV; |
7cca0d81 |
2245 | if (ispkt) { |
2246 | if (pktin.type == SSH2_MSG_CHANNEL_DATA || |
2247 | pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) { |
2248 | char *data; |
2249 | int length; |
2250 | if (ssh2_pkt_getuint32() != 100) |
2251 | continue; /* wrong channel */ |
2252 | if (pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA && |
2253 | ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR) |
2254 | continue; /* extended but not stderr */ |
2255 | ssh2_pkt_getstring(&data, &length); |
2256 | if (data) |
2257 | c_write(data, length); |
2258 | } else if (pktin.type == SSH2_MSG_DISCONNECT) { |
2259 | ssh_state = SSH_STATE_CLOSED; |
2260 | logevent("Received disconnect request"); |
2261 | } else if (pktin.type == SSH2_MSG_CHANNEL_REQUEST) { |
2262 | continue; /* exit status et al; ignore (FIXME?) */ |
2263 | } else if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) { |
2264 | continue; /* ignore for now (FIXME!) */ |
2265 | } else { |
2266 | fatalbox("Strange packet received: type %d", pktin.type); |
2267 | } |
2268 | } else { |
2269 | /* FIXME: for now, ignore window size */ |
2270 | ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA); |
6abbf9e3 |
2271 | ssh2_pkt_adduint32(ssh_remote_channel); |
7cca0d81 |
2272 | ssh2_pkt_addstring_start(); |
2273 | ssh2_pkt_addstring_data(in, inlen); |
2274 | ssh2_pkt_send(); |
2275 | } |
e5574168 |
2276 | } |
2277 | |
2278 | crFinishV; |
2279 | } |
2280 | |
2281 | /* |
7cca0d81 |
2282 | * Handle the top-level SSH2 protocol. |
2283 | */ |
2284 | static void ssh2_protocol(unsigned char *in, int inlen, int ispkt) |
2285 | { |
2286 | if (do_ssh2_transport(in, inlen, ispkt) == 0) |
2287 | return; |
2288 | do_ssh2_authconn(in, inlen, ispkt); |
2289 | } |
2290 | |
2291 | /* |
374330e2 |
2292 | * Called to set up the connection. Will arrange for WM_NETEVENT |
2293 | * messages to be passed to the specified window, whose window |
2294 | * procedure should then call telnet_msg(). |
2295 | * |
2296 | * Returns an error message, or NULL on success. |
374330e2 |
2297 | */ |
2298 | static char *ssh_init (HWND hwnd, char *host, int port, char **realhost) { |
fb09bf1c |
2299 | char *p; |
8f203108 |
2300 | |
2301 | #ifdef MSCRYPTOAPI |
2302 | if(crypto_startup() == 0) |
2303 | return "Microsoft high encryption pack not installed!"; |
2304 | #endif |
374330e2 |
2305 | |
fb09bf1c |
2306 | p = connect_to_host(host, port, realhost); |
2307 | if (p != NULL) |
2308 | return p; |
374330e2 |
2309 | |
2310 | if (!do_ssh_init()) |
2311 | return "Protocol initialisation error"; |
2312 | |
4017be6d |
2313 | if (hwnd && WSAAsyncSelect (s, hwnd, WM_NETEVENT, FD_READ | FD_CLOSE) == SOCKET_ERROR) |
374330e2 |
2314 | switch (WSAGetLastError()) { |
2315 | case WSAENETDOWN: return "Network is down"; |
2316 | default: return "WSAAsyncSelect(): unknown error"; |
2317 | } |
2318 | |
2319 | return NULL; |
2320 | } |
2321 | |
2322 | /* |
2323 | * Process a WM_NETEVENT message. Will return 0 if the connection |
2324 | * has closed, or <0 for a socket error. |
2325 | */ |
2326 | static int ssh_msg (WPARAM wParam, LPARAM lParam) { |
2327 | int ret; |
2328 | char buf[256]; |
2329 | |
8ce72d2c |
2330 | /* |
2331 | * Because reading less than the whole of the available pending |
2332 | * data can generate an FD_READ event, we need to allow for the |
2333 | * possibility that FD_READ may arrive with FD_CLOSE already in |
2334 | * the queue; so it's possible that we can get here even with s |
2335 | * invalid. If so, we return 1 and don't worry about it. |
2336 | */ |
2337 | if (s == INVALID_SOCKET) |
2338 | return 1; |
374330e2 |
2339 | |
2340 | if (WSAGETSELECTERROR(lParam) != 0) |
2341 | return -WSAGETSELECTERROR(lParam); |
2342 | |
2343 | switch (WSAGETSELECTEVENT(lParam)) { |
2344 | case FD_READ: |
8ce72d2c |
2345 | case FD_CLOSE: |
374330e2 |
2346 | ret = recv(s, buf, sizeof(buf), 0); |
2347 | if (ret < 0 && WSAGetLastError() == WSAEWOULDBLOCK) |
2348 | return 1; |
2349 | if (ret < 0) /* any _other_ error */ |
2350 | return -10000-WSAGetLastError(); |
2351 | if (ret == 0) { |
2352 | s = INVALID_SOCKET; |
8ce72d2c |
2353 | return 0; |
374330e2 |
2354 | } |
2355 | ssh_gotdata (buf, ret); |
85ee8208 |
2356 | if (ssh_state == SSH_STATE_CLOSED) { |
2357 | closesocket(s); |
2358 | s = INVALID_SOCKET; |
2359 | return 0; |
2360 | } |
374330e2 |
2361 | return 1; |
374330e2 |
2362 | } |
2363 | return 1; /* shouldn't happen, but WTF */ |
2364 | } |
2365 | |
2366 | /* |
2367 | * Called to send data down the Telnet connection. |
2368 | */ |
2369 | static void ssh_send (char *buf, int len) { |
2370 | if (s == INVALID_SOCKET) |
2371 | return; |
2372 | |
2373 | ssh_protocol(buf, len, 0); |
2374 | } |
2375 | |
2376 | /* |
2377 | * Called to set the size of the window from Telnet's POV. |
2378 | */ |
2379 | static void ssh_size(void) { |
2380 | switch (ssh_state) { |
2381 | case SSH_STATE_BEFORE_SIZE: |
21248260 |
2382 | case SSH_STATE_CLOSED: |
374330e2 |
2383 | break; /* do nothing */ |
2384 | case SSH_STATE_INTERMED: |
2385 | size_needed = TRUE; /* buffer for later */ |
2386 | break; |
2387 | case SSH_STATE_SESSION: |
fef97f43 |
2388 | if (!cfg.nopty) { |
e5574168 |
2389 | send_packet(SSH1_CMSG_WINDOW_SIZE, |
fb09bf1c |
2390 | PKT_INT, rows, PKT_INT, cols, |
2391 | PKT_INT, 0, PKT_INT, 0, PKT_END); |
fef97f43 |
2392 | } |
374330e2 |
2393 | } |
2394 | } |
2395 | |
2396 | /* |
6abbf9e3 |
2397 | * Send Telnet special codes. TS_EOF is useful for `plink', so you |
2398 | * can send an EOF and collect resulting output (e.g. `plink |
2399 | * hostname sort'). |
374330e2 |
2400 | */ |
2401 | static void ssh_special (Telnet_Special code) { |
6abbf9e3 |
2402 | if (code == TS_EOF) { |
2403 | if (ssh_version = 1) { |
2404 | send_packet(SSH1_CMSG_EOF, PKT_END); |
2405 | } else { |
2406 | ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF); |
2407 | ssh2_pkt_adduint32(ssh_remote_channel); |
2408 | ssh2_pkt_send(); |
2409 | } |
2410 | } else { |
2411 | /* do nothing */ |
2412 | } |
374330e2 |
2413 | } |
2414 | |
fb09bf1c |
2415 | |
2416 | /* |
2417 | * Read and decrypt one incoming SSH packet. |
2418 | * (only used by pSCP) |
2419 | */ |
2420 | static void get_packet(void) |
2421 | { |
2422 | unsigned char buf[4096], *p; |
2423 | long to_read; |
2424 | int len; |
2425 | |
fb09bf1c |
2426 | p = NULL; |
2427 | len = 0; |
2428 | |
2429 | while ((to_read = s_rdpkt(&p, &len)) > 0) { |
2430 | if (to_read > sizeof(buf)) to_read = sizeof(buf); |
2431 | len = s_read(buf, to_read); |
2432 | if (len != to_read) { |
2433 | closesocket(s); |
2434 | s = INVALID_SOCKET; |
2435 | return; |
2436 | } |
2437 | p = buf; |
2438 | } |
2439 | |
2440 | assert(len == 0); |
2441 | } |
2442 | |
2443 | /* |
2444 | * Receive a block of data over the SSH link. Block until |
2445 | * all data is available. Return nr of bytes read (0 if lost connection). |
2446 | * (only used by pSCP) |
2447 | */ |
2448 | int ssh_scp_recv(unsigned char *buf, int len) |
2449 | { |
2450 | static int pending_input_len = 0; |
2451 | static unsigned char *pending_input_ptr; |
2452 | int to_read = len; |
2453 | |
fb09bf1c |
2454 | if (pending_input_len >= to_read) { |
2455 | memcpy(buf, pending_input_ptr, to_read); |
2456 | pending_input_ptr += to_read; |
2457 | pending_input_len -= to_read; |
2458 | return len; |
2459 | } |
2460 | |
2461 | if (pending_input_len > 0) { |
2462 | memcpy(buf, pending_input_ptr, pending_input_len); |
2463 | buf += pending_input_len; |
2464 | to_read -= pending_input_len; |
2465 | pending_input_len = 0; |
2466 | } |
2467 | |
2468 | if (s == INVALID_SOCKET) |
2469 | return 0; |
2470 | while (to_read > 0) { |
2471 | get_packet(); |
2472 | if (s == INVALID_SOCKET) |
2473 | return 0; |
e5574168 |
2474 | if (pktin.type == SSH1_SMSG_STDOUT_DATA) { |
fb09bf1c |
2475 | int plen = GET_32BIT(pktin.body); |
2476 | if (plen <= to_read) { |
2477 | memcpy(buf, pktin.body + 4, plen); |
2478 | buf += plen; |
2479 | to_read -= plen; |
2480 | } else { |
2481 | memcpy(buf, pktin.body + 4, to_read); |
2482 | pending_input_len = plen - to_read; |
2483 | pending_input_ptr = pktin.body + 4 + to_read; |
2484 | to_read = 0; |
2485 | } |
e5574168 |
2486 | } else if (pktin.type == SSH1_SMSG_STDERR_DATA) { |
fb09bf1c |
2487 | int plen = GET_32BIT(pktin.body); |
2488 | fwrite(pktin.body + 4, plen, 1, stderr); |
e5574168 |
2489 | } else if (pktin.type == SSH1_MSG_DISCONNECT) { |
fb09bf1c |
2490 | logevent("Received disconnect request"); |
e5574168 |
2491 | } else if (pktin.type == SSH1_SMSG_SUCCESS || |
2492 | pktin.type == SSH1_SMSG_FAILURE) { |
fb09bf1c |
2493 | /* ignore */ |
e5574168 |
2494 | } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) { |
fb09bf1c |
2495 | char logbuf[100]; |
2496 | sprintf(logbuf, "Remote exit status: %d", GET_32BIT(pktin.body)); |
2497 | logevent(logbuf); |
e5574168 |
2498 | send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END); |
fb09bf1c |
2499 | logevent("Closing connection"); |
2500 | closesocket(s); |
2501 | s = INVALID_SOCKET; |
2502 | } else { |
2503 | fatalbox("Strange packet received: type %d", pktin.type); |
2504 | } |
2505 | } |
2506 | |
2507 | return len; |
2508 | } |
2509 | |
2510 | /* |
2511 | * Send a block of data over the SSH link. |
2512 | * Block until all data is sent. |
2513 | * (only used by pSCP) |
2514 | */ |
2515 | void ssh_scp_send(unsigned char *buf, int len) |
2516 | { |
fb09bf1c |
2517 | if (s == INVALID_SOCKET) |
2518 | return; |
e5574168 |
2519 | send_packet(SSH1_CMSG_STDIN_DATA, |
fb09bf1c |
2520 | PKT_INT, len, PKT_DATA, buf, len, PKT_END); |
2521 | } |
2522 | |
2523 | /* |
2524 | * Send an EOF notification to the server. |
2525 | * (only used by pSCP) |
2526 | */ |
2527 | void ssh_scp_send_eof(void) |
2528 | { |
fb09bf1c |
2529 | if (s == INVALID_SOCKET) |
2530 | return; |
e5574168 |
2531 | send_packet(SSH1_CMSG_EOF, PKT_END); |
fb09bf1c |
2532 | } |
2533 | |
2534 | /* |
2535 | * Set up the connection, login on the remote host and |
2536 | * start execution of a command. |
2537 | * Returns an error message, or NULL on success. |
2538 | * (only used by pSCP) |
2539 | */ |
2540 | char *ssh_scp_init(char *host, int port, char *cmd, char **realhost) |
2541 | { |
2542 | char buf[160], *p; |
2543 | |
fb09bf1c |
2544 | #ifdef MSCRYPTOAPI |
2545 | if (crypto_startup() == 0) |
2546 | return "Microsoft high encryption pack not installed!"; |
2547 | #endif |
2548 | |
2549 | p = connect_to_host(host, port, realhost); |
2550 | if (p != NULL) |
2551 | return p; |
2552 | |
2553 | random_init(); |
2554 | |
2555 | if (!do_ssh_init()) |
2556 | return "Protocol initialisation error"; |
2557 | |
2558 | /* Exchange keys and login */ |
2559 | do { |
2560 | get_packet(); |
2561 | if (s == INVALID_SOCKET) |
2562 | return "Connection closed by remote host"; |
e5574168 |
2563 | } while (!do_ssh1_login(NULL, 0, 1)); |
85ee8208 |
2564 | |
2565 | if (ssh_state == SSH_STATE_CLOSED) { |
2566 | closesocket(s); |
2567 | s = INVALID_SOCKET; |
2568 | return "Session initialisation error"; |
2569 | } |
fb09bf1c |
2570 | |
2571 | /* Execute command */ |
2572 | sprintf(buf, "Sending command: %.100s", cmd); |
2573 | logevent(buf); |
e5574168 |
2574 | send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END); |
fb09bf1c |
2575 | |
2576 | return NULL; |
2577 | } |
2578 | |
8ccc75b0 |
2579 | static SOCKET ssh_socket(void) { return s; } |
2580 | |
2581 | static int ssh_sendok(void) { return ssh_send_ok; } |
fb09bf1c |
2582 | |
374330e2 |
2583 | Backend ssh_backend = { |
2584 | ssh_init, |
2585 | ssh_msg, |
2586 | ssh_send, |
2587 | ssh_size, |
4017be6d |
2588 | ssh_special, |
8ccc75b0 |
2589 | ssh_socket, |
2590 | ssh_sendok |
374330e2 |
2591 | }; |