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