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1 | #include <stdio.h> |
2 | #include <stdlib.h> |
fb09bf1c |
3 | #include <stdarg.h> |
4 | #include <assert.h> |
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5 | #include <winsock.h> |
6 | |
7 | #include "putty.h" |
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8 | #include "ssh.h" |
9 | #include "scp.h" |
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10 | |
11 | #ifndef FALSE |
12 | #define FALSE 0 |
13 | #endif |
14 | #ifndef TRUE |
15 | #define TRUE 1 |
16 | #endif |
17 | |
fb09bf1c |
18 | #define logevent(s) { logevent(s); \ |
19 | if (IS_SCP && (scp_flags & SCP_VERBOSE) != 0) \ |
20 | fprintf(stderr, "%s\n", s); } |
21 | |
e5574168 |
22 | #define SSH1_MSG_DISCONNECT 1 |
23 | #define SSH1_SMSG_PUBLIC_KEY 2 |
24 | #define SSH1_CMSG_SESSION_KEY 3 |
25 | #define SSH1_CMSG_USER 4 |
26 | #define SSH1_CMSG_AUTH_PASSWORD 9 |
27 | #define SSH1_CMSG_REQUEST_PTY 10 |
28 | #define SSH1_CMSG_WINDOW_SIZE 11 |
29 | #define SSH1_CMSG_EXEC_SHELL 12 |
30 | #define SSH1_CMSG_EXEC_CMD 13 |
31 | #define SSH1_SMSG_SUCCESS 14 |
32 | #define SSH1_SMSG_FAILURE 15 |
33 | #define SSH1_CMSG_STDIN_DATA 16 |
34 | #define SSH1_SMSG_STDOUT_DATA 17 |
35 | #define SSH1_SMSG_STDERR_DATA 18 |
36 | #define SSH1_CMSG_EOF 19 |
37 | #define SSH1_SMSG_EXIT_STATUS 20 |
38 | #define SSH1_CMSG_EXIT_CONFIRMATION 33 |
39 | #define SSH1_MSG_IGNORE 32 |
40 | #define SSH1_MSG_DEBUG 36 |
41 | #define SSH1_CMSG_AUTH_TIS 39 |
42 | #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 |
43 | #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 |
44 | |
45 | #define SSH1_AUTH_TIS 5 |
46 | |
47 | #define SSH2_MSG_DISCONNECT 1 |
48 | #define SSH2_MSG_IGNORE 2 |
49 | #define SSH2_MSG_UNIMPLEMENTED 3 |
50 | #define SSH2_MSG_DEBUG 4 |
51 | #define SSH2_MSG_SERVICE_REQUEST 5 |
52 | #define SSH2_MSG_SERVICE_ACCEPT 6 |
53 | #define SSH2_MSG_KEXINIT 20 |
54 | #define SSH2_MSG_NEWKEYS 21 |
55 | #define SSH2_MSG_KEXDH_INIT 30 |
56 | #define SSH2_MSG_KEXDH_REPLY 31 |
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57 | |
58 | #define GET_32BIT(cp) \ |
59 | (((unsigned long)(unsigned char)(cp)[0] << 24) | \ |
60 | ((unsigned long)(unsigned char)(cp)[1] << 16) | \ |
61 | ((unsigned long)(unsigned char)(cp)[2] << 8) | \ |
62 | ((unsigned long)(unsigned char)(cp)[3])) |
63 | |
64 | #define PUT_32BIT(cp, value) { \ |
65 | (cp)[0] = (unsigned char)((value) >> 24); \ |
66 | (cp)[1] = (unsigned char)((value) >> 16); \ |
67 | (cp)[2] = (unsigned char)((value) >> 8); \ |
68 | (cp)[3] = (unsigned char)(value); } |
69 | |
70 | enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR }; |
972a41c8 |
71 | |
374330e2 |
72 | /* Coroutine mechanics for the sillier bits of the code */ |
73 | #define crBegin1 static int crLine = 0; |
74 | #define crBegin2 switch(crLine) { case 0:; |
75 | #define crBegin crBegin1; crBegin2; |
76 | #define crFinish(z) } crLine = 0; return (z) |
77 | #define crFinishV } crLine = 0; return |
78 | #define crReturn(z) \ |
79 | do {\ |
80 | crLine=__LINE__; return (z); case __LINE__:;\ |
81 | } while (0) |
82 | #define crReturnV \ |
83 | do {\ |
84 | crLine=__LINE__; return; case __LINE__:;\ |
85 | } while (0) |
86 | #define crStop(z) do{ crLine = 0; return (z); }while(0) |
87 | #define crStopV do{ crLine = 0; return; }while(0) |
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88 | #define crWaitUntil(c) do { crReturn(0); } while (!(c)) |
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89 | |
e5574168 |
90 | extern struct ssh_cipher ssh_3des; |
033b4cef |
91 | extern struct ssh_cipher ssh_3des_ssh2; |
e5574168 |
92 | extern struct ssh_cipher ssh_des; |
93 | extern struct ssh_cipher ssh_blowfish; |
94 | |
95 | /* for ssh 2; we miss out single-DES because it isn't supported */ |
033b4cef |
96 | struct ssh_cipher *ciphers[] = { &ssh_3des_ssh2, &ssh_blowfish }; |
e5574168 |
97 | |
98 | extern struct ssh_kex ssh_diffiehellman; |
99 | struct ssh_kex *kex_algs[] = { &ssh_diffiehellman }; |
100 | |
101 | extern struct ssh_hostkey ssh_dss; |
102 | struct ssh_hostkey *hostkey_algs[] = { &ssh_dss }; |
103 | |
104 | extern struct ssh_mac ssh_sha1; |
105 | |
106 | SHA_State exhash; |
107 | |
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108 | static void nullmac_key(unsigned char *key) { } |
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109 | static void nullmac_generate(unsigned char *blk, int len, unsigned long seq) { } |
110 | static int nullmac_verify(unsigned char *blk, int len, unsigned long seq) { return 1; } |
111 | struct ssh_mac ssh_mac_none = { |
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112 | nullmac_key, nullmac_key, nullmac_generate, nullmac_verify, "none", 0 |
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113 | }; |
114 | struct ssh_mac *macs[] = { &ssh_sha1, &ssh_mac_none }; |
115 | |
116 | struct ssh_compress ssh_comp_none = { |
117 | "none" |
118 | }; |
119 | struct ssh_compress *compressions[] = { &ssh_comp_none }; |
120 | |
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121 | static SOCKET s = INVALID_SOCKET; |
122 | |
123 | static unsigned char session_key[32]; |
124 | static struct ssh_cipher *cipher = NULL; |
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125 | static struct ssh_cipher *cscipher = NULL; |
126 | static struct ssh_cipher *sccipher = NULL; |
127 | static struct ssh_mac *csmac = NULL; |
128 | static struct ssh_mac *scmac = NULL; |
129 | static struct ssh_compress *cscomp = NULL; |
130 | static struct ssh_compress *sccomp = NULL; |
131 | static struct ssh_kex *kex = NULL; |
132 | static struct ssh_hostkey *hostkey = NULL; |
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133 | int scp_flags = 0; |
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134 | int (*ssh_get_password)(const char *prompt, char *str, int maxlen) = NULL; |
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135 | |
136 | static char *savedhost; |
137 | |
138 | static enum { |
139 | SSH_STATE_BEFORE_SIZE, |
140 | SSH_STATE_INTERMED, |
21248260 |
141 | SSH_STATE_SESSION, |
142 | SSH_STATE_CLOSED |
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143 | } ssh_state = SSH_STATE_BEFORE_SIZE; |
144 | |
145 | static int size_needed = FALSE; |
146 | |
147 | static void s_write (char *buf, int len) { |
148 | while (len > 0) { |
149 | int i = send (s, buf, len, 0); |
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150 | if (IS_SCP) { |
151 | noise_ultralight(i); |
152 | if (i <= 0) |
153 | fatalbox("Lost connection while sending"); |
154 | } |
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155 | if (i > 0) |
156 | len -= i, buf += i; |
157 | } |
158 | } |
159 | |
160 | static int s_read (char *buf, int len) { |
161 | int ret = 0; |
162 | while (len > 0) { |
163 | int i = recv (s, buf, len, 0); |
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164 | if (IS_SCP) |
165 | noise_ultralight(i); |
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166 | if (i > 0) |
167 | len -= i, buf += i, ret += i; |
168 | else |
169 | return i; |
170 | } |
171 | return ret; |
172 | } |
173 | |
174 | static void c_write (char *buf, int len) { |
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175 | if (IS_SCP) { |
176 | if (len > 0 && buf[len-1] == '\n') len--; |
177 | if (len > 0 && buf[len-1] == '\r') len--; |
178 | if (len > 0) { fwrite(buf, len, 1, stderr); fputc('\n', stderr); } |
179 | return; |
180 | } |
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181 | while (len--) |
182 | c_write1(*buf++); |
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183 | } |
184 | |
185 | struct Packet { |
186 | long length; |
187 | int type; |
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188 | unsigned char *data; |
189 | unsigned char *body; |
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190 | long savedpos; |
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191 | long maxlen; |
192 | }; |
193 | |
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194 | static struct Packet pktin = { 0, 0, NULL, NULL, 0 }; |
195 | static struct Packet pktout = { 0, 0, NULL, NULL, 0 }; |
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196 | |
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197 | static void (*ssh_protocol)(unsigned char *in, int inlen, int ispkt); |
198 | static void ssh1_protocol(unsigned char *in, int inlen, int ispkt); |
199 | static void ssh2_protocol(unsigned char *in, int inlen, int ispkt); |
374330e2 |
200 | static void ssh_size(void); |
201 | |
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202 | static int (*s_rdpkt)(unsigned char **data, int *datalen); |
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203 | |
204 | /* |
205 | * Collect incoming data in the incoming packet buffer. |
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206 | * Decipher and verify the packet when it is completely read. |
207 | * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets. |
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208 | * Update the *data and *datalen variables. |
209 | * Return the additional nr of bytes needed, or 0 when |
210 | * a complete packet is available. |
211 | */ |
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212 | static int ssh1_rdpkt(unsigned char **data, int *datalen) |
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213 | { |
214 | static long len, pad, biglen, to_read; |
572f871e |
215 | static unsigned long realcrc, gotcrc; |
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216 | static unsigned char *p; |
217 | static int i; |
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218 | |
219 | crBegin; |
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220 | |
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221 | next_packet: |
37508af4 |
222 | |
fb09bf1c |
223 | pktin.type = 0; |
224 | pktin.length = 0; |
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225 | |
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226 | for (i = len = 0; i < 4; i++) { |
227 | while ((*datalen) == 0) |
228 | crReturn(4-i); |
229 | len = (len << 8) + **data; |
230 | (*data)++, (*datalen)--; |
231 | } |
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232 | |
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233 | #ifdef FWHACK |
234 | if (len == 0x52656d6f) { /* "Remo"te server has closed ... */ |
235 | len = 0x300; /* big enough to carry to end */ |
236 | } |
237 | #endif |
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238 | |
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239 | pad = 8 - (len % 8); |
240 | biglen = len + pad; |
241 | pktin.length = len - 5; |
242 | |
243 | if (pktin.maxlen < biglen) { |
244 | pktin.maxlen = biglen; |
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245 | pktin.data = (pktin.data == NULL ? malloc(biglen+APIEXTRA) : |
246 | realloc(pktin.data, biglen+APIEXTRA)); |
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247 | if (!pktin.data) |
248 | fatalbox("Out of memory"); |
249 | } |
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250 | |
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251 | to_read = biglen; |
252 | p = pktin.data; |
253 | while (to_read > 0) { |
254 | static int chunk; |
255 | chunk = to_read; |
256 | while ((*datalen) == 0) |
257 | crReturn(to_read); |
258 | if (chunk > (*datalen)) |
259 | chunk = (*datalen); |
260 | memcpy(p, *data, chunk); |
261 | *data += chunk; |
262 | *datalen -= chunk; |
263 | p += chunk; |
264 | to_read -= chunk; |
265 | } |
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266 | |
fb09bf1c |
267 | if (cipher) |
268 | cipher->decrypt(pktin.data, biglen); |
374330e2 |
269 | |
fb09bf1c |
270 | pktin.type = pktin.data[pad]; |
271 | pktin.body = pktin.data + pad + 1; |
374330e2 |
272 | |
fb09bf1c |
273 | realcrc = crc32(pktin.data, biglen-4); |
274 | gotcrc = GET_32BIT(pktin.data+biglen-4); |
275 | if (gotcrc != realcrc) { |
276 | fatalbox("Incorrect CRC received on packet"); |
277 | } |
572f871e |
278 | |
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279 | if (pktin.type == SSH1_SMSG_STDOUT_DATA || |
280 | pktin.type == SSH1_SMSG_STDERR_DATA || |
281 | pktin.type == SSH1_MSG_DEBUG || |
282 | pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE) { |
fb09bf1c |
283 | long strlen = GET_32BIT(pktin.body); |
284 | if (strlen + 4 != pktin.length) |
285 | fatalbox("Received data packet with bogus string length"); |
286 | } |
287 | |
e5574168 |
288 | if (pktin.type == SSH1_MSG_DEBUG) { |
fb09bf1c |
289 | /* log debug message */ |
290 | char buf[80]; |
291 | int strlen = GET_32BIT(pktin.body); |
292 | strcpy(buf, "Remote: "); |
293 | if (strlen > 70) strlen = 70; |
294 | memcpy(buf+8, pktin.body+4, strlen); |
295 | buf[8+strlen] = '\0'; |
296 | logevent(buf); |
297 | goto next_packet; |
e5574168 |
298 | } else if (pktin.type == SSH1_MSG_IGNORE) { |
fb09bf1c |
299 | /* do nothing */ |
300 | goto next_packet; |
301 | } |
302 | |
303 | crFinish(0); |
304 | } |
305 | |
e5574168 |
306 | static int ssh2_rdpkt(unsigned char **data, int *datalen) |
307 | { |
308 | static long len, pad, payload, packetlen, maclen; |
309 | static int i; |
310 | static int cipherblk; |
311 | static unsigned long incoming_sequence = 0; |
312 | |
313 | crBegin; |
314 | |
315 | next_packet: |
316 | |
317 | pktin.type = 0; |
318 | pktin.length = 0; |
319 | |
320 | if (cipher) |
321 | cipherblk = cipher->blksize; |
322 | else |
323 | cipherblk = 8; |
324 | if (cipherblk < 8) |
325 | cipherblk = 8; |
326 | |
327 | if (pktin.maxlen < cipherblk) { |
328 | pktin.maxlen = cipherblk; |
329 | pktin.data = (pktin.data == NULL ? malloc(cipherblk+APIEXTRA) : |
330 | realloc(pktin.data, cipherblk+APIEXTRA)); |
331 | if (!pktin.data) |
332 | fatalbox("Out of memory"); |
333 | } |
334 | |
335 | /* |
336 | * Acquire and decrypt the first block of the packet. This will |
337 | * contain the length and padding details. |
338 | */ |
339 | for (i = len = 0; i < cipherblk; i++) { |
340 | while ((*datalen) == 0) |
341 | crReturn(cipherblk-i); |
342 | pktin.data[i] = *(*data)++; |
343 | (*datalen)--; |
344 | } |
345 | #ifdef FWHACK |
346 | if (!memcmp(pktin.data, "Remo", 4)) {/* "Remo"te server has closed ... */ |
347 | /* FIXME */ |
348 | } |
349 | #endif |
d39f364a |
350 | debug(("Got initblk:")); |
351 | for (i = 0; i < cipherblk; i++) |
352 | debug((" %02x", (unsigned char)pktin.data[i])); |
353 | debug(("\r\n")); |
e5574168 |
354 | if (sccipher) |
355 | sccipher->decrypt(pktin.data, cipherblk); |
d39f364a |
356 | debug(("Decrypted initblk:")); |
357 | for (i = 0; i < cipherblk; i++) |
358 | debug((" %02x", (unsigned char)pktin.data[i])); |
359 | debug(("\r\n")); |
e5574168 |
360 | |
361 | /* |
362 | * Now get the length and padding figures. |
363 | */ |
364 | len = GET_32BIT(pktin.data); |
365 | pad = pktin.data[4]; |
366 | |
367 | /* |
368 | * This enables us to deduce the payload length. |
369 | */ |
370 | payload = len - pad - 1; |
371 | |
372 | pktin.length = payload + 5; |
373 | |
374 | /* |
375 | * So now we can work out the total packet length. |
376 | */ |
377 | packetlen = len + 4; |
378 | maclen = scmac ? scmac->len : 0; |
379 | |
380 | /* |
381 | * Adjust memory allocation if packet is too big. |
382 | */ |
383 | if (pktin.maxlen < packetlen) { |
384 | pktin.maxlen = packetlen; |
385 | pktin.data = (pktin.data == NULL ? malloc(packetlen+APIEXTRA) : |
386 | realloc(pktin.data, packetlen+APIEXTRA)); |
387 | if (!pktin.data) |
388 | fatalbox("Out of memory"); |
389 | } |
390 | |
391 | /* |
392 | * Read and decrypt the remainder of the packet. |
393 | */ |
394 | for (i = cipherblk; i < packetlen + maclen; i++) { |
395 | while ((*datalen) == 0) |
396 | crReturn(packetlen + maclen - i); |
397 | pktin.data[i] = *(*data)++; |
398 | (*datalen)--; |
399 | } |
400 | /* Decrypt everything _except_ the MAC. */ |
401 | if (sccipher) |
402 | sccipher->decrypt(pktin.data + cipherblk, packetlen - cipherblk); |
403 | |
d39f364a |
404 | debug(("Got packet len=%d pad=%d\r\n", len, pad)); |
405 | for (i = 0; i < packetlen; i++) |
406 | debug((" %02x", (unsigned char)pktin.data[i])); |
407 | debug(("\r\n")); |
408 | |
e5574168 |
409 | /* |
410 | * Check the MAC. |
411 | */ |
033b4cef |
412 | if (scmac && !scmac->verify(pktin.data, len+4, incoming_sequence)) |
e5574168 |
413 | fatalbox("Incorrect MAC received on packet"); |
033b4cef |
414 | incoming_sequence++; /* whether or not we MACed */ |
e5574168 |
415 | |
416 | pktin.savedpos = 6; |
417 | pktin.type = pktin.data[5]; |
e5574168 |
418 | |
419 | /* |
420 | * FIXME: handle IGNORE and DEBUG messages. |
421 | */ |
422 | |
423 | crFinish(0); |
424 | } |
425 | |
fb09bf1c |
426 | static void ssh_gotdata(unsigned char *data, int datalen) |
427 | { |
428 | while (datalen > 0) { |
85ee8208 |
429 | if ( s_rdpkt(&data, &datalen) == 0 ) { |
374330e2 |
430 | ssh_protocol(NULL, 0, 1); |
85ee8208 |
431 | if (ssh_state == SSH_STATE_CLOSED) { |
432 | return; |
433 | } |
434 | } |
374330e2 |
435 | } |
374330e2 |
436 | } |
437 | |
fb09bf1c |
438 | |
374330e2 |
439 | static void s_wrpkt_start(int type, int len) { |
440 | int pad, biglen; |
441 | |
442 | len += 5; /* type and CRC */ |
443 | pad = 8 - (len%8); |
444 | biglen = len + pad; |
445 | |
446 | pktout.length = len-5; |
447 | if (pktout.maxlen < biglen) { |
448 | pktout.maxlen = biglen; |
8f203108 |
449 | #ifdef MSCRYPTOAPI |
fb09bf1c |
450 | /* Allocate enough buffer space for extra block |
8f203108 |
451 | * for MS CryptEncrypt() */ |
fb09bf1c |
452 | pktout.data = (pktout.data == NULL ? malloc(biglen+12) : |
453 | realloc(pktout.data, biglen+12)); |
8f203108 |
454 | #else |
c1f5f956 |
455 | pktout.data = (pktout.data == NULL ? malloc(biglen+4) : |
456 | realloc(pktout.data, biglen+4)); |
8f203108 |
457 | #endif |
374330e2 |
458 | if (!pktout.data) |
459 | fatalbox("Out of memory"); |
460 | } |
461 | |
462 | pktout.type = type; |
463 | pktout.body = pktout.data+4+pad+1; |
464 | } |
465 | |
466 | static void s_wrpkt(void) { |
467 | int pad, len, biglen, i; |
468 | unsigned long crc; |
469 | |
470 | len = pktout.length + 5; /* type and CRC */ |
471 | pad = 8 - (len%8); |
472 | biglen = len + pad; |
473 | |
474 | pktout.body[-1] = pktout.type; |
475 | for (i=0; i<pad; i++) |
476 | pktout.data[i+4] = random_byte(); |
477 | crc = crc32(pktout.data+4, biglen-4); |
fb09bf1c |
478 | PUT_32BIT(pktout.data+biglen, crc); |
479 | PUT_32BIT(pktout.data, len); |
374330e2 |
480 | |
481 | if (cipher) |
482 | cipher->encrypt(pktout.data+4, biglen); |
483 | |
484 | s_write(pktout.data, biglen+4); |
485 | } |
486 | |
fb09bf1c |
487 | /* |
488 | * Construct a packet with the specified contents and |
489 | * send it to the server. |
490 | */ |
491 | static void send_packet(int pkttype, ...) |
492 | { |
493 | va_list args; |
494 | unsigned char *p, *argp, argchar; |
495 | unsigned long argint; |
496 | int pktlen, argtype, arglen; |
497 | |
498 | pktlen = 0; |
499 | va_start(args, pkttype); |
500 | while ((argtype = va_arg(args, int)) != PKT_END) { |
501 | switch (argtype) { |
502 | case PKT_INT: |
503 | (void) va_arg(args, int); |
504 | pktlen += 4; |
505 | break; |
506 | case PKT_CHAR: |
507 | (void) va_arg(args, char); |
508 | pktlen++; |
509 | break; |
510 | case PKT_DATA: |
511 | (void) va_arg(args, unsigned char *); |
512 | arglen = va_arg(args, int); |
513 | pktlen += arglen; |
514 | break; |
515 | case PKT_STR: |
516 | argp = va_arg(args, unsigned char *); |
517 | arglen = strlen(argp); |
518 | pktlen += 4 + arglen; |
519 | break; |
520 | default: |
521 | assert(0); |
522 | } |
523 | } |
524 | va_end(args); |
525 | |
526 | s_wrpkt_start(pkttype, pktlen); |
527 | p = pktout.body; |
528 | |
529 | va_start(args, pkttype); |
530 | while ((argtype = va_arg(args, int)) != PKT_END) { |
531 | switch (argtype) { |
532 | case PKT_INT: |
533 | argint = va_arg(args, int); |
534 | PUT_32BIT(p, argint); |
535 | p += 4; |
536 | break; |
537 | case PKT_CHAR: |
538 | argchar = va_arg(args, unsigned char); |
539 | *p = argchar; |
540 | p++; |
541 | break; |
542 | case PKT_DATA: |
543 | argp = va_arg(args, unsigned char *); |
544 | arglen = va_arg(args, int); |
545 | memcpy(p, argp, arglen); |
546 | p += arglen; |
547 | break; |
548 | case PKT_STR: |
549 | argp = va_arg(args, unsigned char *); |
550 | arglen = strlen(argp); |
551 | PUT_32BIT(p, arglen); |
552 | memcpy(p + 4, argp, arglen); |
553 | p += 4 + arglen; |
554 | break; |
555 | } |
556 | } |
557 | va_end(args); |
558 | |
559 | s_wrpkt(); |
560 | } |
561 | |
562 | |
563 | /* |
564 | * Connect to specified host and port. |
565 | * Returns an error message, or NULL on success. |
566 | * Also places the canonical host name into `realhost'. |
567 | */ |
568 | static char *connect_to_host(char *host, int port, char **realhost) |
569 | { |
570 | SOCKADDR_IN addr; |
571 | struct hostent *h; |
572 | unsigned long a; |
573 | #ifdef FWHACK |
574 | char *FWhost; |
575 | int FWport; |
576 | #endif |
577 | |
578 | savedhost = malloc(1+strlen(host)); |
579 | if (!savedhost) |
580 | fatalbox("Out of memory"); |
581 | strcpy(savedhost, host); |
582 | |
583 | if (port < 0) |
584 | port = 22; /* default ssh port */ |
585 | |
586 | #ifdef FWHACK |
587 | FWhost = host; |
588 | FWport = port; |
589 | host = FWSTR; |
590 | port = 23; |
591 | #endif |
592 | |
593 | /* |
594 | * Try to find host. |
595 | */ |
596 | if ( (a = inet_addr(host)) == (unsigned long) INADDR_NONE) { |
597 | if ( (h = gethostbyname(host)) == NULL) |
598 | switch (WSAGetLastError()) { |
599 | case WSAENETDOWN: return "Network is down"; |
600 | case WSAHOST_NOT_FOUND: case WSANO_DATA: |
601 | return "Host does not exist"; |
602 | case WSATRY_AGAIN: return "Host not found"; |
603 | default: return "gethostbyname: unknown error"; |
604 | } |
605 | memcpy (&a, h->h_addr, sizeof(a)); |
606 | *realhost = h->h_name; |
607 | } else |
608 | *realhost = host; |
609 | #ifdef FWHACK |
610 | *realhost = FWhost; |
611 | #endif |
612 | a = ntohl(a); |
613 | |
614 | /* |
615 | * Open socket. |
616 | */ |
617 | s = socket(AF_INET, SOCK_STREAM, 0); |
618 | if (s == INVALID_SOCKET) |
619 | switch (WSAGetLastError()) { |
620 | case WSAENETDOWN: return "Network is down"; |
621 | case WSAEAFNOSUPPORT: return "TCP/IP support not present"; |
622 | default: return "socket(): unknown error"; |
623 | } |
624 | |
625 | /* |
626 | * Bind to local address. |
627 | */ |
628 | addr.sin_family = AF_INET; |
629 | addr.sin_addr.s_addr = htonl(INADDR_ANY); |
630 | addr.sin_port = htons(0); |
631 | if (bind (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR) |
632 | switch (WSAGetLastError()) { |
633 | case WSAENETDOWN: return "Network is down"; |
634 | default: return "bind(): unknown error"; |
635 | } |
636 | |
637 | /* |
638 | * Connect to remote address. |
639 | */ |
640 | addr.sin_addr.s_addr = htonl(a); |
641 | addr.sin_port = htons((short)port); |
642 | if (connect (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR) |
643 | switch (WSAGetLastError()) { |
644 | case WSAENETDOWN: return "Network is down"; |
645 | case WSAECONNREFUSED: return "Connection refused"; |
646 | case WSAENETUNREACH: return "Network is unreachable"; |
647 | case WSAEHOSTUNREACH: return "No route to host"; |
648 | default: return "connect(): unknown error"; |
649 | } |
650 | |
651 | #ifdef FWHACK |
652 | send(s, "connect ", 8, 0); |
653 | send(s, FWhost, strlen(FWhost), 0); |
654 | { |
655 | char buf[20]; |
656 | sprintf(buf, " %d\n", FWport); |
657 | send (s, buf, strlen(buf), 0); |
658 | } |
659 | #endif |
660 | |
661 | return NULL; |
662 | } |
663 | |
9697bfd2 |
664 | static int ssh_versioncmp(char *a, char *b) { |
665 | char *ae, *be; |
666 | unsigned long av, bv; |
667 | |
43aa02a7 |
668 | av = strtoul(a, &ae, 10); |
669 | bv = strtoul(b, &be, 10); |
9697bfd2 |
670 | if (av != bv) return (av < bv ? -1 : +1); |
671 | if (*ae == '.') ae++; |
672 | if (*be == '.') be++; |
43aa02a7 |
673 | av = strtoul(ae, &ae, 10); |
674 | bv = strtoul(be, &be, 10); |
9697bfd2 |
675 | if (av != bv) return (av < bv ? -1 : +1); |
676 | return 0; |
677 | } |
678 | |
e5574168 |
679 | |
680 | /* |
681 | * Utility routine for putting an SSH-protocol `string' into a SHA |
682 | * state. |
683 | */ |
684 | #include <stdio.h> |
685 | void sha_string(SHA_State *s, void *str, int len) { |
686 | unsigned char lenblk[4]; |
687 | static FILE *fp; |
688 | PUT_32BIT(lenblk, len); |
689 | if (!fp) fp = fopen("h:\\statham\\windows\\putty\\data","wb"); |
690 | fwrite(lenblk, 4, 1, fp); |
691 | SHA_Bytes(s, lenblk, 4); |
692 | fwrite(str, len, 1, fp); |
693 | fflush(fp); |
694 | SHA_Bytes(s, str, len); |
695 | } |
696 | |
374330e2 |
697 | static int do_ssh_init(void) { |
c5e9c988 |
698 | char c, *vsp; |
374330e2 |
699 | char version[10]; |
c5e9c988 |
700 | char vstring[80]; |
701 | char vlog[sizeof(vstring)+20]; |
374330e2 |
702 | int i; |
703 | |
704 | #ifdef FWHACK |
705 | i = 0; |
706 | while (s_read(&c, 1) == 1) { |
707 | if (c == 'S' && i < 2) i++; |
708 | else if (c == 'S' && i == 2) i = 2; |
709 | else if (c == 'H' && i == 2) break; |
710 | else i = 0; |
711 | } |
712 | #else |
713 | if (s_read(&c,1) != 1 || c != 'S') return 0; |
714 | if (s_read(&c,1) != 1 || c != 'S') return 0; |
715 | if (s_read(&c,1) != 1 || c != 'H') return 0; |
716 | #endif |
c5e9c988 |
717 | strcpy(vstring, "SSH-"); |
718 | vsp = vstring+4; |
374330e2 |
719 | if (s_read(&c,1) != 1 || c != '-') return 0; |
720 | i = 0; |
721 | while (1) { |
722 | if (s_read(&c,1) != 1) |
723 | return 0; |
c5e9c988 |
724 | if (vsp < vstring+sizeof(vstring)-1) |
725 | *vsp++ = c; |
374330e2 |
726 | if (i >= 0) { |
727 | if (c == '-') { |
728 | version[i] = '\0'; |
729 | i = -1; |
730 | } else if (i < sizeof(version)-1) |
731 | version[i++] = c; |
732 | } |
733 | else if (c == '\n') |
734 | break; |
735 | } |
736 | |
c5e9c988 |
737 | *vsp = 0; |
738 | sprintf(vlog, "Server version: %s", vstring); |
739 | vlog[strcspn(vlog, "\r\n")] = '\0'; |
740 | logevent(vlog); |
741 | |
e5574168 |
742 | if (ssh_versioncmp(version, "1.99") >= 0) { |
743 | /* |
744 | * This is a v2 server. Begin v2 protocol. |
745 | */ |
746 | char *verstring = "SSH-2.0-PuTTY"; |
747 | SHA_Init(&exhash); |
748 | /* |
749 | * Hash our version string and their version string. |
750 | */ |
751 | sha_string(&exhash, verstring, strlen(verstring)); |
752 | sha_string(&exhash, vstring, strcspn(vstring, "\r\n")); |
753 | sprintf(vstring, "%s\n", verstring); |
754 | sprintf(vlog, "We claim version: %s", verstring); |
755 | logevent(vlog); |
756 | logevent("Using SSH protocol version 2"); |
757 | s_write(vstring, strlen(vstring)); |
758 | ssh_protocol = ssh2_protocol; |
759 | s_rdpkt = ssh2_rdpkt; |
760 | } else { |
761 | /* |
762 | * This is a v1 server. Begin v1 protocol. |
763 | */ |
764 | sprintf(vstring, "SSH-%s-PuTTY\n", |
765 | (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5")); |
766 | sprintf(vlog, "We claim version: %s", vstring); |
767 | vlog[strcspn(vlog, "\r\n")] = '\0'; |
768 | logevent(vlog); |
769 | logevent("Using SSH protocol version 1"); |
770 | s_write(vstring, strlen(vstring)); |
771 | ssh_protocol = ssh1_protocol; |
772 | s_rdpkt = ssh1_rdpkt; |
773 | } |
fef97f43 |
774 | return 1; |
374330e2 |
775 | } |
776 | |
fb09bf1c |
777 | /* |
778 | * Handle the key exchange and user authentication phases. |
779 | */ |
e5574168 |
780 | static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) |
fb09bf1c |
781 | { |
374330e2 |
782 | int i, j, len; |
783 | unsigned char session_id[16]; |
784 | unsigned char *rsabuf, *keystr1, *keystr2; |
785 | unsigned char cookie[8]; |
786 | struct RSAKey servkey, hostkey; |
787 | struct MD5Context md5c; |
ccbfb941 |
788 | static unsigned long supported_ciphers_mask, supported_auths_mask; |
bea1ef5f |
789 | int cipher_type; |
374330e2 |
790 | |
374330e2 |
791 | crBegin; |
792 | |
fb09bf1c |
793 | if (!ispkt) crWaitUntil(ispkt); |
374330e2 |
794 | |
e5574168 |
795 | if (pktin.type != SSH1_SMSG_PUBLIC_KEY) |
374330e2 |
796 | fatalbox("Public key packet not received"); |
797 | |
c5e9c988 |
798 | logevent("Received public keys"); |
374330e2 |
799 | |
c5e9c988 |
800 | memcpy(cookie, pktin.body, 8); |
374330e2 |
801 | |
802 | i = makekey(pktin.body+8, &servkey, &keystr1); |
374330e2 |
803 | j = makekey(pktin.body+8+i, &hostkey, &keystr2); |
804 | |
c5e9c988 |
805 | /* |
806 | * Hash the host key and print the hash in the log box. Just as |
807 | * a last resort in case the registry's host key checking is |
808 | * compromised, we'll allow the user some ability to verify |
809 | * host keys by eye. |
810 | */ |
811 | MD5Init(&md5c); |
812 | MD5Update(&md5c, keystr2, hostkey.bytes); |
813 | MD5Final(session_id, &md5c); |
814 | { |
815 | char logmsg[80]; |
816 | int i; |
817 | logevent("Host key MD5 is:"); |
818 | strcpy(logmsg, " "); |
819 | for (i = 0; i < 16; i++) |
820 | sprintf(logmsg+strlen(logmsg), "%02x", session_id[i]); |
821 | logevent(logmsg); |
822 | } |
823 | |
fb09bf1c |
824 | supported_ciphers_mask = GET_32BIT(pktin.body+12+i+j); |
825 | supported_auths_mask = GET_32BIT(pktin.body+16+i+j); |
bea1ef5f |
826 | |
c5e9c988 |
827 | MD5Init(&md5c); |
374330e2 |
828 | MD5Update(&md5c, keystr2, hostkey.bytes); |
829 | MD5Update(&md5c, keystr1, servkey.bytes); |
830 | MD5Update(&md5c, pktin.body, 8); |
374330e2 |
831 | MD5Final(session_id, &md5c); |
832 | |
833 | for (i=0; i<32; i++) |
834 | session_key[i] = random_byte(); |
835 | |
836 | len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes); |
837 | |
838 | rsabuf = malloc(len); |
839 | if (!rsabuf) |
840 | fatalbox("Out of memory"); |
841 | |
89ee5268 |
842 | /* |
843 | * Verify the host key. |
844 | */ |
845 | { |
846 | /* |
847 | * First format the key into a string. |
848 | */ |
849 | int len = rsastr_len(&hostkey); |
850 | char *keystr = malloc(len); |
851 | if (!keystr) |
852 | fatalbox("Out of memory"); |
853 | rsastr_fmt(keystr, &hostkey); |
854 | verify_ssh_host_key(savedhost, keystr); |
855 | free(keystr); |
856 | } |
374330e2 |
857 | |
858 | for (i=0; i<32; i++) { |
859 | rsabuf[i] = session_key[i]; |
860 | if (i < 16) |
861 | rsabuf[i] ^= session_id[i]; |
862 | } |
863 | |
864 | if (hostkey.bytes > servkey.bytes) { |
865 | rsaencrypt(rsabuf, 32, &servkey); |
866 | rsaencrypt(rsabuf, servkey.bytes, &hostkey); |
867 | } else { |
868 | rsaencrypt(rsabuf, 32, &hostkey); |
869 | rsaencrypt(rsabuf, hostkey.bytes, &servkey); |
870 | } |
871 | |
c5e9c988 |
872 | logevent("Encrypted session key"); |
873 | |
bea1ef5f |
874 | cipher_type = cfg.cipher == CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH : |
9697bfd2 |
875 | cfg.cipher == CIPHER_DES ? SSH_CIPHER_DES : |
bea1ef5f |
876 | SSH_CIPHER_3DES; |
877 | if ((supported_ciphers_mask & (1 << cipher_type)) == 0) { |
878 | c_write("Selected cipher not supported, falling back to 3DES\r\n", 53); |
879 | cipher_type = SSH_CIPHER_3DES; |
880 | } |
c5e9c988 |
881 | switch (cipher_type) { |
882 | case SSH_CIPHER_3DES: logevent("Using 3DES encryption"); break; |
883 | case SSH_CIPHER_DES: logevent("Using single-DES encryption"); break; |
884 | case SSH_CIPHER_BLOWFISH: logevent("Using Blowfish encryption"); break; |
885 | } |
bea1ef5f |
886 | |
e5574168 |
887 | send_packet(SSH1_CMSG_SESSION_KEY, |
fb09bf1c |
888 | PKT_CHAR, cipher_type, |
889 | PKT_DATA, cookie, 8, |
890 | PKT_CHAR, (len*8) >> 8, PKT_CHAR, (len*8) & 0xFF, |
891 | PKT_DATA, rsabuf, len, |
892 | PKT_INT, 0, |
893 | PKT_END); |
894 | |
c5e9c988 |
895 | logevent("Trying to enable encryption..."); |
374330e2 |
896 | |
897 | free(rsabuf); |
898 | |
bea1ef5f |
899 | cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish : |
9697bfd2 |
900 | cipher_type == SSH_CIPHER_DES ? &ssh_des : |
bea1ef5f |
901 | &ssh_3des; |
374330e2 |
902 | cipher->sesskey(session_key); |
903 | |
fb09bf1c |
904 | crWaitUntil(ispkt); |
374330e2 |
905 | |
e5574168 |
906 | if (pktin.type != SSH1_SMSG_SUCCESS) |
374330e2 |
907 | fatalbox("Encryption not successfully enabled"); |
908 | |
c5e9c988 |
909 | logevent("Successfully started encryption"); |
910 | |
374330e2 |
911 | fflush(stdout); |
912 | { |
913 | static char username[100]; |
914 | static int pos = 0; |
915 | static char c; |
fb09bf1c |
916 | if (!IS_SCP && !*cfg.username) { |
374330e2 |
917 | c_write("login as: ", 10); |
918 | while (pos >= 0) { |
fb09bf1c |
919 | crWaitUntil(!ispkt); |
374330e2 |
920 | while (inlen--) switch (c = *in++) { |
921 | case 10: case 13: |
922 | username[pos] = 0; |
923 | pos = -1; |
924 | break; |
925 | case 8: case 127: |
926 | if (pos > 0) { |
927 | c_write("\b \b", 3); |
928 | pos--; |
929 | } |
930 | break; |
931 | case 21: case 27: |
932 | while (pos > 0) { |
933 | c_write("\b \b", 3); |
934 | pos--; |
935 | } |
936 | break; |
937 | case 3: case 4: |
938 | random_save_seed(); |
939 | exit(0); |
940 | break; |
941 | default: |
40d24aa6 |
942 | if (((c >= ' ' && c <= '~') || |
943 | ((unsigned char)c >= 160)) && pos < 40) { |
374330e2 |
944 | username[pos++] = c; |
945 | c_write(&c, 1); |
946 | } |
947 | break; |
948 | } |
949 | } |
950 | c_write("\r\n", 2); |
951 | username[strcspn(username, "\n\r")] = '\0'; |
952 | } else { |
953 | char stuff[200]; |
954 | strncpy(username, cfg.username, 99); |
955 | username[99] = '\0'; |
fb09bf1c |
956 | if (!IS_SCP) { |
957 | sprintf(stuff, "Sent username \"%s\".\r\n", username); |
958 | c_write(stuff, strlen(stuff)); |
959 | } |
374330e2 |
960 | } |
fb09bf1c |
961 | |
e5574168 |
962 | send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END); |
c5e9c988 |
963 | { |
964 | char userlog[20+sizeof(username)]; |
965 | sprintf(userlog, "Sent username \"%s\"", username); |
966 | logevent(userlog); |
967 | } |
374330e2 |
968 | } |
969 | |
fb09bf1c |
970 | crWaitUntil(ispkt); |
374330e2 |
971 | |
e5574168 |
972 | while (pktin.type == SSH1_SMSG_FAILURE) { |
374330e2 |
973 | static char password[100]; |
974 | static int pos; |
975 | static char c; |
ccbfb941 |
976 | static int pwpkt_type; |
977 | |
978 | /* |
979 | * Show password prompt, having first obtained it via a TIS |
980 | * exchange if we're doing TIS authentication. |
981 | */ |
e5574168 |
982 | pwpkt_type = SSH1_CMSG_AUTH_PASSWORD; |
fb09bf1c |
983 | |
984 | if (IS_SCP) { |
985 | char prompt[200]; |
986 | sprintf(prompt, "%s@%s's password: ", cfg.username, savedhost); |
85ee8208 |
987 | if (!ssh_get_password(prompt, password, sizeof(password))) { |
988 | /* |
989 | * get_password failed to get a password (for |
990 | * example because one was supplied on the command |
991 | * line which has already failed to work). |
992 | * Terminate. |
993 | */ |
994 | logevent("No more passwords to try"); |
995 | ssh_state = SSH_STATE_CLOSED; |
996 | crReturn(1); |
997 | } |
fb09bf1c |
998 | } else { |
999 | |
e5574168 |
1000 | if (pktin.type == SSH1_SMSG_FAILURE && |
ccbfb941 |
1001 | cfg.try_tis_auth && |
e5574168 |
1002 | (supported_auths_mask & (1<<SSH1_AUTH_TIS))) { |
1003 | pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE; |
c5e9c988 |
1004 | logevent("Requested TIS authentication"); |
e5574168 |
1005 | send_packet(SSH1_CMSG_AUTH_TIS, PKT_END); |
fb09bf1c |
1006 | crWaitUntil(ispkt); |
e5574168 |
1007 | if (pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) { |
c5e9c988 |
1008 | logevent("TIS authentication declined"); |
ccbfb941 |
1009 | c_write("TIS authentication refused.\r\n", 29); |
1010 | } else { |
1011 | int challengelen = ((pktin.body[0] << 24) | |
1012 | (pktin.body[1] << 16) | |
1013 | (pktin.body[2] << 8) | |
1014 | (pktin.body[3])); |
c5e9c988 |
1015 | logevent("Received TIS challenge"); |
ccbfb941 |
1016 | c_write(pktin.body+4, challengelen); |
1017 | } |
1018 | } |
e5574168 |
1019 | if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) |
ccbfb941 |
1020 | c_write("password: ", 10); |
1021 | |
374330e2 |
1022 | pos = 0; |
1023 | while (pos >= 0) { |
fb09bf1c |
1024 | crWaitUntil(!ispkt); |
374330e2 |
1025 | while (inlen--) switch (c = *in++) { |
1026 | case 10: case 13: |
1027 | password[pos] = 0; |
1028 | pos = -1; |
1029 | break; |
1030 | case 8: case 127: |
1031 | if (pos > 0) |
1032 | pos--; |
1033 | break; |
1034 | case 21: case 27: |
1035 | pos = 0; |
1036 | break; |
1037 | case 3: case 4: |
1038 | random_save_seed(); |
1039 | exit(0); |
1040 | break; |
1041 | default: |
40d24aa6 |
1042 | if (((c >= ' ' && c <= '~') || |
1043 | ((unsigned char)c >= 160)) && pos < 40) |
374330e2 |
1044 | password[pos++] = c; |
1045 | break; |
1046 | } |
1047 | } |
1048 | c_write("\r\n", 2); |
fb09bf1c |
1049 | |
1050 | } |
1051 | |
1052 | send_packet(pwpkt_type, PKT_STR, password, PKT_END); |
c5e9c988 |
1053 | logevent("Sent password"); |
374330e2 |
1054 | memset(password, 0, strlen(password)); |
fb09bf1c |
1055 | crWaitUntil(ispkt); |
e5574168 |
1056 | if (pktin.type == SSH1_SMSG_FAILURE) { |
374330e2 |
1057 | c_write("Access denied\r\n", 15); |
c5e9c988 |
1058 | logevent("Authentication refused"); |
e5574168 |
1059 | } else if (pktin.type == SSH1_MSG_DISCONNECT) { |
fb09bf1c |
1060 | logevent("Received disconnect request"); |
85ee8208 |
1061 | ssh_state = SSH_STATE_CLOSED; |
1062 | crReturn(1); |
e5574168 |
1063 | } else if (pktin.type != SSH1_SMSG_SUCCESS) { |
374330e2 |
1064 | fatalbox("Strange packet received, type %d", pktin.type); |
1065 | } |
1066 | } |
1067 | |
c5e9c988 |
1068 | logevent("Authentication successful"); |
1069 | |
fb09bf1c |
1070 | crFinish(1); |
1071 | } |
1072 | |
e5574168 |
1073 | static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) { |
fb09bf1c |
1074 | crBegin; |
1075 | |
1076 | random_init(); |
1077 | |
e5574168 |
1078 | while (!do_ssh1_login(in, inlen, ispkt)) { |
fb09bf1c |
1079 | crReturnV; |
85ee8208 |
1080 | } |
1081 | if (ssh_state == SSH_STATE_CLOSED) |
1082 | crReturnV; |
fb09bf1c |
1083 | |
fef97f43 |
1084 | if (!cfg.nopty) { |
e5574168 |
1085 | send_packet(SSH1_CMSG_REQUEST_PTY, |
fb09bf1c |
1086 | PKT_STR, cfg.termtype, |
1087 | PKT_INT, rows, PKT_INT, cols, |
1088 | PKT_INT, 0, PKT_INT, 0, |
1089 | PKT_CHAR, 0, |
1090 | PKT_END); |
fef97f43 |
1091 | ssh_state = SSH_STATE_INTERMED; |
1092 | do { crReturnV; } while (!ispkt); |
e5574168 |
1093 | if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) { |
fef97f43 |
1094 | fatalbox("Protocol confusion"); |
e5574168 |
1095 | } else if (pktin.type == SSH1_SMSG_FAILURE) { |
fef97f43 |
1096 | c_write("Server refused to allocate pty\r\n", 32); |
1097 | } |
c5e9c988 |
1098 | logevent("Allocated pty"); |
374330e2 |
1099 | } |
1100 | |
e5574168 |
1101 | send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END); |
c5e9c988 |
1102 | logevent("Started session"); |
374330e2 |
1103 | |
1104 | ssh_state = SSH_STATE_SESSION; |
1105 | if (size_needed) |
1106 | ssh_size(); |
1107 | |
1108 | while (1) { |
1109 | crReturnV; |
1110 | if (ispkt) { |
e5574168 |
1111 | if (pktin.type == SSH1_SMSG_STDOUT_DATA || |
1112 | pktin.type == SSH1_SMSG_STDERR_DATA) { |
fb09bf1c |
1113 | long len = GET_32BIT(pktin.body); |
1114 | c_write(pktin.body+4, len); |
e5574168 |
1115 | } else if (pktin.type == SSH1_MSG_DISCONNECT) { |
21248260 |
1116 | ssh_state = SSH_STATE_CLOSED; |
c5e9c988 |
1117 | logevent("Received disconnect request"); |
e5574168 |
1118 | } else if (pktin.type == SSH1_SMSG_SUCCESS) { |
972a41c8 |
1119 | /* may be from EXEC_SHELL on some servers */ |
e5574168 |
1120 | } else if (pktin.type == SSH1_SMSG_FAILURE) { |
972a41c8 |
1121 | /* may be from EXEC_SHELL on some servers |
374330e2 |
1122 | * if no pty is available or in other odd cases. Ignore */ |
e5574168 |
1123 | } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) { |
1124 | send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END); |
374330e2 |
1125 | } else { |
1126 | fatalbox("Strange packet received: type %d", pktin.type); |
1127 | } |
1128 | } else { |
e5574168 |
1129 | send_packet(SSH1_CMSG_STDIN_DATA, |
fb09bf1c |
1130 | PKT_INT, inlen, PKT_DATA, in, inlen, PKT_END); |
374330e2 |
1131 | } |
1132 | } |
1133 | |
1134 | crFinishV; |
1135 | } |
1136 | |
1137 | /* |
e5574168 |
1138 | * SSH2 packet construction functions. |
1139 | */ |
1140 | void ssh2_pkt_adddata(void *data, int len) { |
1141 | pktout.length += len; |
1142 | if (pktout.maxlen < pktout.length) { |
1143 | pktout.maxlen = pktout.length + 256; |
1144 | pktout.data = (pktout.data == NULL ? malloc(pktout.maxlen+APIEXTRA) : |
1145 | realloc(pktout.data, pktout.maxlen+APIEXTRA)); |
1146 | if (!pktout.data) |
1147 | fatalbox("Out of memory"); |
1148 | } |
1149 | memcpy(pktout.data+pktout.length-len, data, len); |
1150 | } |
1151 | void ssh2_pkt_addbyte(unsigned char byte) { |
1152 | ssh2_pkt_adddata(&byte, 1); |
1153 | } |
1154 | void ssh2_pkt_init(int pkt_type) { |
1155 | pktout.length = 5; |
1156 | ssh2_pkt_addbyte((unsigned char)pkt_type); |
1157 | } |
1158 | void ssh2_pkt_addbool(unsigned char value) { |
1159 | ssh2_pkt_adddata(&value, 1); |
1160 | } |
1161 | void ssh2_pkt_adduint32(unsigned long value) { |
1162 | unsigned char x[4]; |
1163 | PUT_32BIT(x, value); |
1164 | ssh2_pkt_adddata(x, 4); |
1165 | } |
1166 | void ssh2_pkt_addstring_start(void) { |
1167 | ssh2_pkt_adduint32(0); |
1168 | pktout.savedpos = pktout.length; |
1169 | } |
1170 | void ssh2_pkt_addstring_str(char *data) { |
1171 | ssh2_pkt_adddata(data, strlen(data)); |
1172 | PUT_32BIT(pktout.data + pktout.savedpos - 4, |
1173 | pktout.length - pktout.savedpos); |
1174 | } |
1175 | void ssh2_pkt_addstring_data(char *data, int len) { |
1176 | ssh2_pkt_adddata(data, len); |
1177 | PUT_32BIT(pktout.data + pktout.savedpos - 4, |
1178 | pktout.length - pktout.savedpos); |
1179 | } |
1180 | void ssh2_pkt_addstring(char *data) { |
1181 | ssh2_pkt_addstring_start(); |
1182 | ssh2_pkt_addstring_str(data); |
1183 | } |
1184 | char *ssh2_mpint_fmt(Bignum b, int *len) { |
1185 | unsigned char *p; |
1186 | int i, n = b[0]; |
1187 | p = malloc(n * 2 + 1); |
1188 | if (!p) |
1189 | fatalbox("out of memory"); |
1190 | p[0] = 0; |
1191 | for (i = 0; i < n; i++) { |
1192 | p[i*2+1] = (b[n-i] >> 8) & 0xFF; |
1193 | p[i*2+2] = (b[n-i] ) & 0xFF; |
1194 | } |
1195 | i = 0; |
1196 | while (p[i] == 0 && (p[i+1] & 0x80) == 0) |
1197 | i++; |
1198 | memmove(p, p+i, n*2+1-i); |
1199 | *len = n*2+1-i; |
1200 | return p; |
1201 | } |
1202 | void ssh2_pkt_addmp(Bignum b) { |
1203 | unsigned char *p; |
1204 | int len; |
1205 | p = ssh2_mpint_fmt(b, &len); |
1206 | ssh2_pkt_addstring_start(); |
1207 | ssh2_pkt_addstring_data(p, len); |
1208 | free(p); |
1209 | } |
1210 | void ssh2_pkt_send(void) { |
1211 | int cipherblk, maclen, padding, i; |
033b4cef |
1212 | static unsigned long outgoing_sequence = 0; |
e5574168 |
1213 | |
1214 | /* |
1215 | * Add padding. At least four bytes, and must also bring total |
1216 | * length (minus MAC) up to a multiple of the block size. |
1217 | */ |
1218 | cipherblk = cipher ? cipher->blksize : 8; /* block size */ |
1219 | cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */ |
1220 | padding = 4; |
1221 | padding += (cipherblk - (pktout.length + padding) % cipherblk) % cipherblk; |
1222 | pktout.data[4] = padding; |
1223 | for (i = 0; i < padding; i++) |
1224 | pktout.data[pktout.length + i] = random_byte(); |
1225 | PUT_32BIT(pktout.data, pktout.length + padding - 4); |
1226 | if (csmac) |
033b4cef |
1227 | csmac->generate(pktout.data, pktout.length + padding, |
1228 | outgoing_sequence); |
1229 | outgoing_sequence++; /* whether or not we MACed */ |
e5574168 |
1230 | if (cscipher) |
1231 | cscipher->encrypt(pktout.data, pktout.length + padding); |
1232 | maclen = csmac ? csmac->len : 0; |
1233 | #if 0 |
1234 | debug(("Sending packet len=%d\r\n", pktout.length+padding+maclen)); |
1235 | for (i = 0; i < pktout.length+padding+maclen; i++) |
1236 | debug((" %02x", (unsigned char)pktout.data[i])); |
1237 | debug(("\r\n")); |
1238 | #endif |
1239 | s_write(pktout.data, pktout.length + padding + maclen); |
1240 | } |
1241 | |
1242 | void sha_mpint(SHA_State *s, Bignum b) { |
1243 | unsigned char *p; |
1244 | int len; |
1245 | p = ssh2_mpint_fmt(b, &len); |
1246 | sha_string(s, p, len); |
1247 | free(p); |
1248 | } |
1249 | |
1250 | /* |
1251 | * SSH2 packet decode functions. |
1252 | */ |
1253 | void ssh2_pkt_getstring(char **p, int *length) { |
1254 | *p = NULL; |
1255 | if (pktin.length - pktin.savedpos < 4) |
1256 | return; |
1257 | *length = GET_32BIT(pktin.data+pktin.savedpos); |
1258 | pktin.savedpos += 4; |
1259 | if (pktin.length - pktin.savedpos < *length) |
1260 | return; |
1261 | *p = pktin.data+pktin.savedpos; |
1262 | pktin.savedpos += *length; |
1263 | } |
1264 | Bignum ssh2_pkt_getmp(void) { |
1265 | char *p; |
1266 | int i, j, length; |
1267 | Bignum b; |
1268 | |
1269 | ssh2_pkt_getstring(&p, &length); |
1270 | if (!p) |
1271 | return NULL; |
1272 | if (p[0] & 0x80) |
1273 | fatalbox("internal error: Can't handle negative mpints"); |
1274 | b = newbn((length+1)/2); |
1275 | for (i = 0; i < length; i++) { |
1276 | j = length - 1 - i; |
1277 | if (j & 1) |
1278 | b[j/2+1] |= ((unsigned char)p[i]) << 8; |
1279 | else |
1280 | b[j/2+1] |= ((unsigned char)p[i]); |
1281 | } |
1282 | return b; |
1283 | } |
1284 | |
1285 | void bndebug(char *string, Bignum b) { |
1286 | unsigned char *p; |
1287 | int i, len; |
1288 | p = ssh2_mpint_fmt(b, &len); |
1289 | debug(("%s", string)); |
1290 | for (i = 0; i < len; i++) |
1291 | debug((" %02x", p[i])); |
1292 | debug(("\r\n")); |
1293 | free(p); |
1294 | } |
1295 | |
1296 | /* |
1297 | * Utility routine for decoding comma-separated strings in KEXINIT. |
1298 | */ |
1299 | int in_commasep_string(char *needle, char *haystack, int haylen) { |
1300 | int needlen = strlen(needle); |
1301 | while (1) { |
1302 | /* |
1303 | * Is it at the start of the string? |
1304 | */ |
1305 | if (haylen >= needlen && /* haystack is long enough */ |
1306 | !memcmp(needle, haystack, needlen) && /* initial match */ |
1307 | (haylen == needlen || haystack[needlen] == ',') |
1308 | /* either , or EOS follows */ |
1309 | ) |
1310 | return 1; |
1311 | /* |
1312 | * If not, search for the next comma and resume after that. |
1313 | * If no comma found, terminate. |
1314 | */ |
1315 | while (haylen > 0 && *haystack != ',') |
1316 | haylen--, haystack++; |
1317 | if (haylen == 0) |
1318 | return 0; |
1319 | haylen--, haystack++; /* skip over comma itself */ |
1320 | } |
1321 | } |
1322 | |
1323 | /* |
d39f364a |
1324 | * SSH2 key creation method. |
1325 | */ |
1326 | void ssh2_mkkey(Bignum K, char *H, char chr, char *keyspace) { |
1327 | SHA_State s; |
1328 | /* First 20 bytes. */ |
1329 | SHA_Init(&s); |
1330 | sha_mpint(&s, K); |
1331 | SHA_Bytes(&s, H, 20); |
1332 | SHA_Bytes(&s, &chr, 1); |
1333 | SHA_Bytes(&s, H, 20); |
1334 | SHA_Final(&s, keyspace); |
1335 | /* Next 20 bytes. */ |
1336 | SHA_Init(&s); |
1337 | sha_mpint(&s, K); |
1338 | SHA_Bytes(&s, H, 20); |
1339 | SHA_Bytes(&s, keyspace, 20); |
1340 | SHA_Final(&s, keyspace+20); |
1341 | } |
1342 | |
1343 | /* |
e5574168 |
1344 | * Handle the SSH2 key exchange phase. |
1345 | */ |
1346 | static int do_ssh2_kex(unsigned char *in, int inlen, int ispkt) |
1347 | { |
1348 | static int i, len; |
1349 | static char *str; |
1350 | static Bignum e, f, K; |
1351 | static struct ssh_cipher *cscipher_tobe = NULL; |
1352 | static struct ssh_cipher *sccipher_tobe = NULL; |
1353 | static struct ssh_mac *csmac_tobe = NULL; |
1354 | static struct ssh_mac *scmac_tobe = NULL; |
1355 | static struct ssh_compress *cscomp_tobe = NULL; |
1356 | static struct ssh_compress *sccomp_tobe = NULL; |
1357 | static char *hostkeydata, *sigdata; |
1358 | static int hostkeylen, siglen; |
1359 | static unsigned char exchange_hash[20]; |
d39f364a |
1360 | static unsigned char keyspace[40]; |
e5574168 |
1361 | |
1362 | crBegin; |
1363 | |
1364 | /* |
1365 | * Construct and send our key exchange packet. |
1366 | */ |
1367 | ssh2_pkt_init(SSH2_MSG_KEXINIT); |
1368 | for (i = 0; i < 16; i++) |
1369 | ssh2_pkt_addbyte((unsigned char)random_byte()); |
1370 | /* List key exchange algorithms. */ |
1371 | ssh2_pkt_addstring_start(); |
1372 | for (i = 0; i < lenof(kex_algs); i++) { |
1373 | ssh2_pkt_addstring_str(kex_algs[i]->name); |
1374 | if (i < lenof(kex_algs)-1) |
1375 | ssh2_pkt_addstring_str(","); |
1376 | } |
1377 | /* List server host key algorithms. */ |
1378 | ssh2_pkt_addstring_start(); |
1379 | for (i = 0; i < lenof(hostkey_algs); i++) { |
1380 | ssh2_pkt_addstring_str(hostkey_algs[i]->name); |
1381 | if (i < lenof(hostkey_algs)-1) |
1382 | ssh2_pkt_addstring_str(","); |
1383 | } |
1384 | /* List client->server encryption algorithms. */ |
1385 | ssh2_pkt_addstring_start(); |
1386 | for (i = 0; i < lenof(ciphers); i++) { |
1387 | ssh2_pkt_addstring_str(ciphers[i]->name); |
1388 | if (i < lenof(ciphers)-1) |
1389 | ssh2_pkt_addstring_str(","); |
1390 | } |
1391 | /* List server->client encryption algorithms. */ |
1392 | ssh2_pkt_addstring_start(); |
1393 | for (i = 0; i < lenof(ciphers); i++) { |
1394 | ssh2_pkt_addstring_str(ciphers[i]->name); |
1395 | if (i < lenof(ciphers)-1) |
1396 | ssh2_pkt_addstring_str(","); |
1397 | } |
1398 | /* List client->server MAC algorithms. */ |
1399 | ssh2_pkt_addstring_start(); |
1400 | for (i = 0; i < lenof(macs); i++) { |
1401 | ssh2_pkt_addstring_str(macs[i]->name); |
1402 | if (i < lenof(macs)-1) |
1403 | ssh2_pkt_addstring_str(","); |
1404 | } |
1405 | /* List server->client MAC algorithms. */ |
1406 | ssh2_pkt_addstring_start(); |
1407 | for (i = 0; i < lenof(macs); i++) { |
1408 | ssh2_pkt_addstring_str(macs[i]->name); |
1409 | if (i < lenof(macs)-1) |
1410 | ssh2_pkt_addstring_str(","); |
1411 | } |
1412 | /* List client->server compression algorithms. */ |
1413 | ssh2_pkt_addstring_start(); |
1414 | for (i = 0; i < lenof(compressions); i++) { |
1415 | ssh2_pkt_addstring_str(compressions[i]->name); |
1416 | if (i < lenof(compressions)-1) |
1417 | ssh2_pkt_addstring_str(","); |
1418 | } |
1419 | /* List server->client compression algorithms. */ |
1420 | ssh2_pkt_addstring_start(); |
1421 | for (i = 0; i < lenof(compressions); i++) { |
1422 | ssh2_pkt_addstring_str(compressions[i]->name); |
1423 | if (i < lenof(compressions)-1) |
1424 | ssh2_pkt_addstring_str(","); |
1425 | } |
1426 | /* List client->server languages. Empty list. */ |
1427 | ssh2_pkt_addstring_start(); |
1428 | /* List server->client languages. Empty list. */ |
1429 | ssh2_pkt_addstring_start(); |
1430 | /* First KEX packet does _not_ follow, because we're not that brave. */ |
1431 | ssh2_pkt_addbool(FALSE); |
1432 | /* Reserved. */ |
1433 | ssh2_pkt_adduint32(0); |
1434 | sha_string(&exhash, pktout.data+5, pktout.length-5); |
1435 | ssh2_pkt_send(); |
1436 | |
1437 | if (!ispkt) crWaitUntil(ispkt); |
1438 | sha_string(&exhash, pktin.data+5, pktin.length-5); |
1439 | |
1440 | /* |
1441 | * Now examine the other side's KEXINIT to see what we're up |
1442 | * to. |
1443 | */ |
1444 | if (pktin.type != SSH2_MSG_KEXINIT) |
1445 | fatalbox("expected key exchange packet from server"); |
1446 | kex = NULL; hostkey = NULL; cscipher_tobe = NULL; sccipher_tobe = NULL; |
1447 | csmac_tobe = NULL; scmac_tobe = NULL; cscomp_tobe = NULL; sccomp_tobe = NULL; |
1448 | pktin.savedpos += 16; /* skip garbage cookie */ |
1449 | ssh2_pkt_getstring(&str, &len); /* key exchange algorithms */ |
1450 | for (i = 0; i < lenof(kex_algs); i++) { |
1451 | if (in_commasep_string(kex_algs[i]->name, str, len)) { |
1452 | kex = kex_algs[i]; |
1453 | break; |
1454 | } |
1455 | } |
1456 | ssh2_pkt_getstring(&str, &len); /* host key algorithms */ |
1457 | for (i = 0; i < lenof(hostkey_algs); i++) { |
1458 | if (in_commasep_string(hostkey_algs[i]->name, str, len)) { |
1459 | hostkey = hostkey_algs[i]; |
1460 | break; |
1461 | } |
1462 | } |
1463 | ssh2_pkt_getstring(&str, &len); /* client->server cipher */ |
1464 | for (i = 0; i < lenof(ciphers); i++) { |
1465 | if (in_commasep_string(ciphers[i]->name, str, len)) { |
1466 | cscipher_tobe = ciphers[i]; |
1467 | break; |
1468 | } |
1469 | } |
1470 | ssh2_pkt_getstring(&str, &len); /* server->client cipher */ |
1471 | for (i = 0; i < lenof(ciphers); i++) { |
1472 | if (in_commasep_string(ciphers[i]->name, str, len)) { |
1473 | sccipher_tobe = ciphers[i]; |
1474 | break; |
1475 | } |
1476 | } |
1477 | ssh2_pkt_getstring(&str, &len); /* client->server mac */ |
1478 | for (i = 0; i < lenof(macs); i++) { |
1479 | if (in_commasep_string(macs[i]->name, str, len)) { |
1480 | csmac_tobe = macs[i]; |
1481 | break; |
1482 | } |
1483 | } |
1484 | ssh2_pkt_getstring(&str, &len); /* server->client mac */ |
1485 | for (i = 0; i < lenof(macs); i++) { |
1486 | if (in_commasep_string(macs[i]->name, str, len)) { |
1487 | scmac_tobe = macs[i]; |
1488 | break; |
1489 | } |
1490 | } |
1491 | ssh2_pkt_getstring(&str, &len); /* client->server compression */ |
1492 | for (i = 0; i < lenof(compressions); i++) { |
1493 | if (in_commasep_string(compressions[i]->name, str, len)) { |
1494 | cscomp_tobe = compressions[i]; |
1495 | break; |
1496 | } |
1497 | } |
1498 | ssh2_pkt_getstring(&str, &len); /* server->client compression */ |
1499 | for (i = 0; i < lenof(compressions); i++) { |
1500 | if (in_commasep_string(compressions[i]->name, str, len)) { |
1501 | sccomp_tobe = compressions[i]; |
1502 | break; |
1503 | } |
1504 | } |
1505 | debug(("key exchange is %s\r\n", kex ? kex->name : NULL)); |
1506 | debug(("host key alg is %s\r\n", hostkey ? hostkey->name : NULL)); |
1507 | debug(("cscipher alg is %s\r\n", cscipher_tobe ? cscipher_tobe->name : NULL)); |
1508 | debug(("sccipher alg is %s\r\n", sccipher_tobe ? sccipher_tobe->name : NULL)); |
1509 | debug(("csmac alg is %s\r\n", csmac_tobe ? csmac_tobe->name : NULL)); |
1510 | debug(("scmac alg is %s\r\n", scmac_tobe ? scmac_tobe->name : NULL)); |
1511 | debug(("cscomp alg is %s\r\n", cscomp_tobe ? cscomp_tobe->name : NULL)); |
1512 | debug(("sccomp alg is %s\r\n", sccomp_tobe ? sccomp_tobe->name : NULL)); |
1513 | |
1514 | /* |
1515 | * Currently we only support Diffie-Hellman and DSS, so let's |
1516 | * bomb out if those aren't selected. |
1517 | */ |
1518 | if (kex != &ssh_diffiehellman || hostkey != &ssh_dss) |
1519 | fatalbox("internal fault: chaos in SSH 2 transport layer"); |
1520 | |
1521 | /* |
1522 | * Now we begin the fun. Generate and send e for Diffie-Hellman. |
1523 | */ |
1524 | e = dh_create_e(); |
1525 | bndebug("e=", e); |
1526 | ssh2_pkt_init(SSH2_MSG_KEXDH_INIT); |
1527 | ssh2_pkt_addmp(e); |
1528 | ssh2_pkt_send(); |
1529 | |
1530 | crWaitUntil(ispkt); |
1531 | if (pktin.type != SSH2_MSG_KEXDH_REPLY) |
1532 | fatalbox("expected key exchange packet from server"); |
1533 | ssh2_pkt_getstring(&hostkeydata, &hostkeylen); |
1534 | f = ssh2_pkt_getmp(); |
1535 | bndebug("f=", f); |
1536 | ssh2_pkt_getstring(&sigdata, &siglen); |
1537 | |
1538 | K = dh_find_K(f); |
1539 | bndebug("K=", K); |
1540 | |
1541 | sha_string(&exhash, hostkeydata, hostkeylen); |
1542 | sha_mpint(&exhash, e); |
1543 | sha_mpint(&exhash, f); |
1544 | sha_mpint(&exhash, K); |
1545 | SHA_Final(&exhash, exchange_hash); |
1546 | |
1547 | debug(("Exchange hash is:\r\n")); |
1548 | for (i = 0; i < 20; i++) |
1549 | debug((" %02x", exchange_hash[i])); |
1550 | debug(("\r\n")); |
1551 | |
1552 | /* |
d39f364a |
1553 | * FIXME: verify host key. This bit will be moderately |
1554 | * unpleasant, because of having to rewrite it to work |
1555 | * alongside the old scheme. |
1556 | */ |
1557 | |
1558 | /* |
1559 | * FIXME: verify signature of exchange hash. |
e5574168 |
1560 | */ |
d39f364a |
1561 | |
1562 | /* |
1563 | * Send SSH2_MSG_NEWKEYS. Expect it from server. |
1564 | */ |
1565 | ssh2_pkt_init(SSH2_MSG_NEWKEYS); |
1566 | ssh2_pkt_send(); |
1567 | crWaitUntil(ispkt); |
1568 | if (pktin.type != SSH2_MSG_NEWKEYS) |
1569 | fatalbox("expected new-keys packet from server"); |
1570 | |
1571 | /* |
1572 | * Create and initialise session keys. |
1573 | */ |
1574 | cscipher = cscipher_tobe; |
1575 | sccipher = sccipher_tobe; |
1576 | csmac = csmac_tobe; |
1577 | scmac = scmac_tobe; |
1578 | cscomp = cscomp_tobe; |
1579 | sccomp = sccomp_tobe; |
1580 | /* |
1581 | * Set IVs after keys. |
1582 | */ |
1583 | ssh2_mkkey(K, exchange_hash, 'C', keyspace); cscipher->setcskey(keyspace); |
1584 | ssh2_mkkey(K, exchange_hash, 'D', keyspace); cscipher->setsckey(keyspace); |
1585 | ssh2_mkkey(K, exchange_hash, 'A', keyspace); cscipher->setcsiv(keyspace); |
1586 | ssh2_mkkey(K, exchange_hash, 'B', keyspace); sccipher->setsciv(keyspace); |
1587 | ssh2_mkkey(K, exchange_hash, 'E', keyspace); csmac->setcskey(keyspace); |
1588 | ssh2_mkkey(K, exchange_hash, 'F', keyspace); scmac->setsckey(keyspace); |
1589 | |
033b4cef |
1590 | /* |
1591 | * Now we're encrypting. Send a test packet (FIXME). |
1592 | */ |
1593 | crWaitUntil(!ispkt); |
1594 | ssh2_pkt_init(SSH2_MSG_IGNORE); |
1595 | ssh2_pkt_addstring("oo-er"); |
1596 | ssh2_pkt_send(); |
1597 | |
e5574168 |
1598 | crWaitUntil(0); |
1599 | |
1600 | crFinish(1); |
1601 | } |
1602 | |
1603 | static void ssh2_protocol(unsigned char *in, int inlen, int ispkt) { |
1604 | crBegin; |
1605 | |
1606 | random_init(); |
1607 | |
1608 | while (!do_ssh2_kex(in, inlen, ispkt)) { |
1609 | crReturnV; |
1610 | } |
1611 | |
1612 | crFinishV; |
1613 | } |
1614 | |
1615 | /* |
374330e2 |
1616 | * Called to set up the connection. Will arrange for WM_NETEVENT |
1617 | * messages to be passed to the specified window, whose window |
1618 | * procedure should then call telnet_msg(). |
1619 | * |
1620 | * Returns an error message, or NULL on success. |
374330e2 |
1621 | */ |
1622 | static char *ssh_init (HWND hwnd, char *host, int port, char **realhost) { |
fb09bf1c |
1623 | char *p; |
8f203108 |
1624 | |
1625 | #ifdef MSCRYPTOAPI |
1626 | if(crypto_startup() == 0) |
1627 | return "Microsoft high encryption pack not installed!"; |
1628 | #endif |
374330e2 |
1629 | |
fb09bf1c |
1630 | p = connect_to_host(host, port, realhost); |
1631 | if (p != NULL) |
1632 | return p; |
374330e2 |
1633 | |
1634 | if (!do_ssh_init()) |
1635 | return "Protocol initialisation error"; |
1636 | |
1637 | if (WSAAsyncSelect (s, hwnd, WM_NETEVENT, FD_READ | FD_CLOSE) == SOCKET_ERROR) |
1638 | switch (WSAGetLastError()) { |
1639 | case WSAENETDOWN: return "Network is down"; |
1640 | default: return "WSAAsyncSelect(): unknown error"; |
1641 | } |
1642 | |
1643 | return NULL; |
1644 | } |
1645 | |
1646 | /* |
1647 | * Process a WM_NETEVENT message. Will return 0 if the connection |
1648 | * has closed, or <0 for a socket error. |
1649 | */ |
1650 | static int ssh_msg (WPARAM wParam, LPARAM lParam) { |
1651 | int ret; |
1652 | char buf[256]; |
1653 | |
8ce72d2c |
1654 | /* |
1655 | * Because reading less than the whole of the available pending |
1656 | * data can generate an FD_READ event, we need to allow for the |
1657 | * possibility that FD_READ may arrive with FD_CLOSE already in |
1658 | * the queue; so it's possible that we can get here even with s |
1659 | * invalid. If so, we return 1 and don't worry about it. |
1660 | */ |
1661 | if (s == INVALID_SOCKET) |
1662 | return 1; |
374330e2 |
1663 | |
1664 | if (WSAGETSELECTERROR(lParam) != 0) |
1665 | return -WSAGETSELECTERROR(lParam); |
1666 | |
1667 | switch (WSAGETSELECTEVENT(lParam)) { |
1668 | case FD_READ: |
8ce72d2c |
1669 | case FD_CLOSE: |
374330e2 |
1670 | ret = recv(s, buf, sizeof(buf), 0); |
1671 | if (ret < 0 && WSAGetLastError() == WSAEWOULDBLOCK) |
1672 | return 1; |
1673 | if (ret < 0) /* any _other_ error */ |
1674 | return -10000-WSAGetLastError(); |
1675 | if (ret == 0) { |
1676 | s = INVALID_SOCKET; |
8ce72d2c |
1677 | return 0; |
374330e2 |
1678 | } |
1679 | ssh_gotdata (buf, ret); |
85ee8208 |
1680 | if (ssh_state == SSH_STATE_CLOSED) { |
1681 | closesocket(s); |
1682 | s = INVALID_SOCKET; |
1683 | return 0; |
1684 | } |
374330e2 |
1685 | return 1; |
374330e2 |
1686 | } |
1687 | return 1; /* shouldn't happen, but WTF */ |
1688 | } |
1689 | |
1690 | /* |
1691 | * Called to send data down the Telnet connection. |
1692 | */ |
1693 | static void ssh_send (char *buf, int len) { |
1694 | if (s == INVALID_SOCKET) |
1695 | return; |
1696 | |
1697 | ssh_protocol(buf, len, 0); |
1698 | } |
1699 | |
1700 | /* |
1701 | * Called to set the size of the window from Telnet's POV. |
1702 | */ |
1703 | static void ssh_size(void) { |
1704 | switch (ssh_state) { |
1705 | case SSH_STATE_BEFORE_SIZE: |
21248260 |
1706 | case SSH_STATE_CLOSED: |
374330e2 |
1707 | break; /* do nothing */ |
1708 | case SSH_STATE_INTERMED: |
1709 | size_needed = TRUE; /* buffer for later */ |
1710 | break; |
1711 | case SSH_STATE_SESSION: |
fef97f43 |
1712 | if (!cfg.nopty) { |
e5574168 |
1713 | send_packet(SSH1_CMSG_WINDOW_SIZE, |
fb09bf1c |
1714 | PKT_INT, rows, PKT_INT, cols, |
1715 | PKT_INT, 0, PKT_INT, 0, PKT_END); |
fef97f43 |
1716 | } |
374330e2 |
1717 | } |
1718 | } |
1719 | |
1720 | /* |
1721 | * (Send Telnet special codes) |
1722 | */ |
1723 | static void ssh_special (Telnet_Special code) { |
1724 | /* do nothing */ |
1725 | } |
1726 | |
fb09bf1c |
1727 | |
1728 | /* |
1729 | * Read and decrypt one incoming SSH packet. |
1730 | * (only used by pSCP) |
1731 | */ |
1732 | static void get_packet(void) |
1733 | { |
1734 | unsigned char buf[4096], *p; |
1735 | long to_read; |
1736 | int len; |
1737 | |
1738 | assert(IS_SCP); |
1739 | |
1740 | p = NULL; |
1741 | len = 0; |
1742 | |
1743 | while ((to_read = s_rdpkt(&p, &len)) > 0) { |
1744 | if (to_read > sizeof(buf)) to_read = sizeof(buf); |
1745 | len = s_read(buf, to_read); |
1746 | if (len != to_read) { |
1747 | closesocket(s); |
1748 | s = INVALID_SOCKET; |
1749 | return; |
1750 | } |
1751 | p = buf; |
1752 | } |
1753 | |
1754 | assert(len == 0); |
1755 | } |
1756 | |
1757 | /* |
1758 | * Receive a block of data over the SSH link. Block until |
1759 | * all data is available. Return nr of bytes read (0 if lost connection). |
1760 | * (only used by pSCP) |
1761 | */ |
1762 | int ssh_scp_recv(unsigned char *buf, int len) |
1763 | { |
1764 | static int pending_input_len = 0; |
1765 | static unsigned char *pending_input_ptr; |
1766 | int to_read = len; |
1767 | |
1768 | assert(IS_SCP); |
1769 | |
1770 | if (pending_input_len >= to_read) { |
1771 | memcpy(buf, pending_input_ptr, to_read); |
1772 | pending_input_ptr += to_read; |
1773 | pending_input_len -= to_read; |
1774 | return len; |
1775 | } |
1776 | |
1777 | if (pending_input_len > 0) { |
1778 | memcpy(buf, pending_input_ptr, pending_input_len); |
1779 | buf += pending_input_len; |
1780 | to_read -= pending_input_len; |
1781 | pending_input_len = 0; |
1782 | } |
1783 | |
1784 | if (s == INVALID_SOCKET) |
1785 | return 0; |
1786 | while (to_read > 0) { |
1787 | get_packet(); |
1788 | if (s == INVALID_SOCKET) |
1789 | return 0; |
e5574168 |
1790 | if (pktin.type == SSH1_SMSG_STDOUT_DATA) { |
fb09bf1c |
1791 | int plen = GET_32BIT(pktin.body); |
1792 | if (plen <= to_read) { |
1793 | memcpy(buf, pktin.body + 4, plen); |
1794 | buf += plen; |
1795 | to_read -= plen; |
1796 | } else { |
1797 | memcpy(buf, pktin.body + 4, to_read); |
1798 | pending_input_len = plen - to_read; |
1799 | pending_input_ptr = pktin.body + 4 + to_read; |
1800 | to_read = 0; |
1801 | } |
e5574168 |
1802 | } else if (pktin.type == SSH1_SMSG_STDERR_DATA) { |
fb09bf1c |
1803 | int plen = GET_32BIT(pktin.body); |
1804 | fwrite(pktin.body + 4, plen, 1, stderr); |
e5574168 |
1805 | } else if (pktin.type == SSH1_MSG_DISCONNECT) { |
fb09bf1c |
1806 | logevent("Received disconnect request"); |
e5574168 |
1807 | } else if (pktin.type == SSH1_SMSG_SUCCESS || |
1808 | pktin.type == SSH1_SMSG_FAILURE) { |
fb09bf1c |
1809 | /* ignore */ |
e5574168 |
1810 | } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) { |
fb09bf1c |
1811 | char logbuf[100]; |
1812 | sprintf(logbuf, "Remote exit status: %d", GET_32BIT(pktin.body)); |
1813 | logevent(logbuf); |
e5574168 |
1814 | send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END); |
fb09bf1c |
1815 | logevent("Closing connection"); |
1816 | closesocket(s); |
1817 | s = INVALID_SOCKET; |
1818 | } else { |
1819 | fatalbox("Strange packet received: type %d", pktin.type); |
1820 | } |
1821 | } |
1822 | |
1823 | return len; |
1824 | } |
1825 | |
1826 | /* |
1827 | * Send a block of data over the SSH link. |
1828 | * Block until all data is sent. |
1829 | * (only used by pSCP) |
1830 | */ |
1831 | void ssh_scp_send(unsigned char *buf, int len) |
1832 | { |
1833 | assert(IS_SCP); |
1834 | if (s == INVALID_SOCKET) |
1835 | return; |
e5574168 |
1836 | send_packet(SSH1_CMSG_STDIN_DATA, |
fb09bf1c |
1837 | PKT_INT, len, PKT_DATA, buf, len, PKT_END); |
1838 | } |
1839 | |
1840 | /* |
1841 | * Send an EOF notification to the server. |
1842 | * (only used by pSCP) |
1843 | */ |
1844 | void ssh_scp_send_eof(void) |
1845 | { |
1846 | assert(IS_SCP); |
1847 | if (s == INVALID_SOCKET) |
1848 | return; |
e5574168 |
1849 | send_packet(SSH1_CMSG_EOF, PKT_END); |
fb09bf1c |
1850 | } |
1851 | |
1852 | /* |
1853 | * Set up the connection, login on the remote host and |
1854 | * start execution of a command. |
1855 | * Returns an error message, or NULL on success. |
1856 | * (only used by pSCP) |
1857 | */ |
1858 | char *ssh_scp_init(char *host, int port, char *cmd, char **realhost) |
1859 | { |
1860 | char buf[160], *p; |
1861 | |
1862 | assert(IS_SCP); |
1863 | |
1864 | #ifdef MSCRYPTOAPI |
1865 | if (crypto_startup() == 0) |
1866 | return "Microsoft high encryption pack not installed!"; |
1867 | #endif |
1868 | |
1869 | p = connect_to_host(host, port, realhost); |
1870 | if (p != NULL) |
1871 | return p; |
1872 | |
1873 | random_init(); |
1874 | |
1875 | if (!do_ssh_init()) |
1876 | return "Protocol initialisation error"; |
1877 | |
1878 | /* Exchange keys and login */ |
1879 | do { |
1880 | get_packet(); |
1881 | if (s == INVALID_SOCKET) |
1882 | return "Connection closed by remote host"; |
e5574168 |
1883 | } while (!do_ssh1_login(NULL, 0, 1)); |
85ee8208 |
1884 | |
1885 | if (ssh_state == SSH_STATE_CLOSED) { |
1886 | closesocket(s); |
1887 | s = INVALID_SOCKET; |
1888 | return "Session initialisation error"; |
1889 | } |
fb09bf1c |
1890 | |
1891 | /* Execute command */ |
1892 | sprintf(buf, "Sending command: %.100s", cmd); |
1893 | logevent(buf); |
e5574168 |
1894 | send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END); |
fb09bf1c |
1895 | |
1896 | return NULL; |
1897 | } |
1898 | |
1899 | |
374330e2 |
1900 | Backend ssh_backend = { |
1901 | ssh_init, |
1902 | ssh_msg, |
1903 | ssh_send, |
1904 | ssh_size, |
1905 | ssh_special |
1906 | }; |
fb09bf1c |
1907 | |