1 |
/* |
2 |
rdesktop: A Remote Desktop Protocol client. |
3 |
Protocol services - RDP encryption and licensing |
4 |
Copyright (C) Matthew Chapman 1999-2002 |
5 |
|
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This program is free software; you can redistribute it and/or modify |
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it under the terms of the GNU General Public License as published by |
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the Free Software Foundation; either version 2 of the License, or |
9 |
(at your option) any later version. |
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|
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This program is distributed in the hope that it will be useful, |
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but WITHOUT ANY WARRANTY; without even the implied warranty of |
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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GNU General Public License for more details. |
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|
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You should have received a copy of the GNU General Public License |
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along with this program; if not, write to the Free Software |
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Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
19 |
*/ |
20 |
|
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#include "rdesktop.h" |
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|
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#ifdef WITH_OPENSSL |
24 |
#include <openssl/rc4.h> |
25 |
#include <openssl/md5.h> |
26 |
#include <openssl/sha.h> |
27 |
#include <openssl/bn.h> |
28 |
#else |
29 |
#include "crypto/rc4.h" |
30 |
#include "crypto/md5.h" |
31 |
#include "crypto/sha.h" |
32 |
#include "crypto/bn.h" |
33 |
#endif |
34 |
|
35 |
extern char hostname[16]; |
36 |
extern int width; |
37 |
extern int height; |
38 |
extern int keylayout; |
39 |
extern BOOL encryption; |
40 |
extern BOOL licence_issued; |
41 |
extern int server_bpp; |
42 |
|
43 |
static int rc4_key_len; |
44 |
static RC4_KEY rc4_decrypt_key; |
45 |
static RC4_KEY rc4_encrypt_key; |
46 |
|
47 |
static uint8 sec_sign_key[16]; |
48 |
static uint8 sec_decrypt_key[16]; |
49 |
static uint8 sec_encrypt_key[16]; |
50 |
static uint8 sec_decrypt_update_key[16]; |
51 |
static uint8 sec_encrypt_update_key[16]; |
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static uint8 sec_crypted_random[SEC_MODULUS_SIZE]; |
53 |
|
54 |
/* |
55 |
* General purpose 48-byte transformation, using two 32-byte salts (generally, |
56 |
* a client and server salt) and a global salt value used for padding. |
57 |
* Both SHA1 and MD5 algorithms are used. |
58 |
*/ |
59 |
void |
60 |
sec_hash_48(uint8 * out, uint8 * in, uint8 * salt1, uint8 * salt2, uint8 salt) |
61 |
{ |
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uint8 shasig[20]; |
63 |
uint8 pad[4]; |
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SHA_CTX sha; |
65 |
MD5_CTX md5; |
66 |
int i; |
67 |
|
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for (i = 0; i < 3; i++) |
69 |
{ |
70 |
memset(pad, salt + i, i + 1); |
71 |
|
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SHA1_Init(&sha); |
73 |
SHA1_Update(&sha, pad, i + 1); |
74 |
SHA1_Update(&sha, in, 48); |
75 |
SHA1_Update(&sha, salt1, 32); |
76 |
SHA1_Update(&sha, salt2, 32); |
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SHA1_Final(shasig, &sha); |
78 |
|
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MD5_Init(&md5); |
80 |
MD5_Update(&md5, in, 48); |
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MD5_Update(&md5, shasig, 20); |
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MD5_Final(&out[i * 16], &md5); |
83 |
} |
84 |
} |
85 |
|
86 |
/* |
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* Weaker 16-byte transformation, also using two 32-byte salts, but |
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* only using a single round of MD5. |
89 |
*/ |
90 |
void |
91 |
sec_hash_16(uint8 * out, uint8 * in, uint8 * salt1, uint8 * salt2) |
92 |
{ |
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MD5_CTX md5; |
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|
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MD5_Init(&md5); |
96 |
MD5_Update(&md5, in, 16); |
97 |
MD5_Update(&md5, salt1, 32); |
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MD5_Update(&md5, salt2, 32); |
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MD5_Final(out, &md5); |
100 |
} |
101 |
|
102 |
/* Reduce key entropy from 64 to 40 bits */ |
103 |
static void |
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sec_make_40bit(uint8 * key) |
105 |
{ |
106 |
key[0] = 0xd1; |
107 |
key[1] = 0x26; |
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key[2] = 0x9e; |
109 |
} |
110 |
|
111 |
/* Generate a session key and RC4 keys, given client and server randoms */ |
112 |
static void |
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sec_generate_keys(uint8 * client_key, uint8 * server_key, int rc4_key_size) |
114 |
{ |
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uint8 session_key[48]; |
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uint8 temp_hash[48]; |
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uint8 input[48]; |
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|
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/* Construct input data to hash */ |
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memcpy(input, client_key, 24); |
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memcpy(input + 24, server_key, 24); |
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|
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/* Generate session key - two rounds of sec_hash_48 */ |
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sec_hash_48(temp_hash, input, client_key, server_key, 65); |
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sec_hash_48(session_key, temp_hash, client_key, server_key, 88); |
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|
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/* Store first 16 bytes of session key, for generating signatures */ |
128 |
memcpy(sec_sign_key, session_key, 16); |
129 |
|
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/* Generate RC4 keys */ |
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sec_hash_16(sec_decrypt_key, &session_key[16], client_key, server_key); |
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sec_hash_16(sec_encrypt_key, &session_key[32], client_key, server_key); |
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|
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if (rc4_key_size == 1) |
135 |
{ |
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DEBUG(("40-bit encryption enabled\n")); |
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sec_make_40bit(sec_sign_key); |
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sec_make_40bit(sec_decrypt_key); |
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sec_make_40bit(sec_encrypt_key); |
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rc4_key_len = 8; |
141 |
} |
142 |
else |
143 |
{ |
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DEBUG(("128-bit encryption enabled\n")); |
145 |
rc4_key_len = 16; |
146 |
} |
147 |
|
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/* Save initial RC4 keys as update keys */ |
149 |
memcpy(sec_decrypt_update_key, sec_decrypt_key, 16); |
150 |
memcpy(sec_encrypt_update_key, sec_encrypt_key, 16); |
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|
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/* Initialise RC4 state arrays */ |
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RC4_set_key(&rc4_decrypt_key, rc4_key_len, sec_decrypt_key); |
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RC4_set_key(&rc4_encrypt_key, rc4_key_len, sec_encrypt_key); |
155 |
} |
156 |
|
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static uint8 pad_54[40] = { |
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54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, |
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54, 54, 54, |
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54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, |
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54, 54, 54 |
162 |
}; |
163 |
|
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static uint8 pad_92[48] = { |
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92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, |
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92, 92, 92, 92, 92, 92, 92, |
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92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, |
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92, 92, 92, 92, 92, 92, 92 |
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}; |
170 |
|
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/* Output a uint32 into a buffer (little-endian) */ |
172 |
void |
173 |
buf_out_uint32(uint8 * buffer, uint32 value) |
174 |
{ |
175 |
buffer[0] = (value) & 0xff; |
176 |
buffer[1] = (value >> 8) & 0xff; |
177 |
buffer[2] = (value >> 16) & 0xff; |
178 |
buffer[3] = (value >> 24) & 0xff; |
179 |
} |
180 |
|
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/* Generate a signature hash, using a combination of SHA1 and MD5 */ |
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void |
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sec_sign(uint8 * signature, int siglen, uint8 * session_key, int keylen, uint8 * data, int datalen) |
184 |
{ |
185 |
uint8 shasig[20]; |
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uint8 md5sig[16]; |
187 |
uint8 lenhdr[4]; |
188 |
SHA_CTX sha; |
189 |
MD5_CTX md5; |
190 |
|
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buf_out_uint32(lenhdr, datalen); |
192 |
|
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SHA1_Init(&sha); |
194 |
SHA1_Update(&sha, session_key, keylen); |
195 |
SHA1_Update(&sha, pad_54, 40); |
196 |
SHA1_Update(&sha, lenhdr, 4); |
197 |
SHA1_Update(&sha, data, datalen); |
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SHA1_Final(shasig, &sha); |
199 |
|
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MD5_Init(&md5); |
201 |
MD5_Update(&md5, session_key, keylen); |
202 |
MD5_Update(&md5, pad_92, 48); |
203 |
MD5_Update(&md5, shasig, 20); |
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MD5_Final(md5sig, &md5); |
205 |
|
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memcpy(signature, md5sig, siglen); |
207 |
} |
208 |
|
209 |
/* Update an encryption key - similar to the signing process */ |
210 |
static void |
211 |
sec_update(uint8 * key, uint8 * update_key) |
212 |
{ |
213 |
uint8 shasig[20]; |
214 |
SHA_CTX sha; |
215 |
MD5_CTX md5; |
216 |
RC4_KEY update; |
217 |
|
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SHA1_Init(&sha); |
219 |
SHA1_Update(&sha, update_key, rc4_key_len); |
220 |
SHA1_Update(&sha, pad_54, 40); |
221 |
SHA1_Update(&sha, key, rc4_key_len); |
222 |
SHA1_Final(shasig, &sha); |
223 |
|
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MD5_Init(&md5); |
225 |
MD5_Update(&md5, update_key, rc4_key_len); |
226 |
MD5_Update(&md5, pad_92, 48); |
227 |
MD5_Update(&md5, shasig, 20); |
228 |
MD5_Final(key, &md5); |
229 |
|
230 |
RC4_set_key(&update, rc4_key_len, key); |
231 |
RC4(&update, rc4_key_len, key, key); |
232 |
|
233 |
if (rc4_key_len == 8) |
234 |
sec_make_40bit(key); |
235 |
} |
236 |
|
237 |
/* Encrypt data using RC4 */ |
238 |
static void |
239 |
sec_encrypt(uint8 * data, int length) |
240 |
{ |
241 |
static int use_count; |
242 |
|
243 |
if (use_count == 4096) |
244 |
{ |
245 |
sec_update(sec_encrypt_key, sec_encrypt_update_key); |
246 |
RC4_set_key(&rc4_encrypt_key, rc4_key_len, sec_encrypt_key); |
247 |
use_count = 0; |
248 |
} |
249 |
|
250 |
RC4(&rc4_encrypt_key, length, data, data); |
251 |
use_count++; |
252 |
} |
253 |
|
254 |
/* Decrypt data using RC4 */ |
255 |
static void |
256 |
sec_decrypt(uint8 * data, int length) |
257 |
{ |
258 |
static int use_count; |
259 |
|
260 |
if (use_count == 4096) |
261 |
{ |
262 |
sec_update(sec_decrypt_key, sec_decrypt_update_key); |
263 |
RC4_set_key(&rc4_decrypt_key, rc4_key_len, sec_decrypt_key); |
264 |
use_count = 0; |
265 |
} |
266 |
|
267 |
RC4(&rc4_decrypt_key, length, data, data); |
268 |
use_count++; |
269 |
} |
270 |
|
271 |
static void |
272 |
reverse(uint8 * p, int len) |
273 |
{ |
274 |
int i, j; |
275 |
uint8 temp; |
276 |
|
277 |
for (i = 0, j = len - 1; i < j; i++, j--) |
278 |
{ |
279 |
temp = p[i]; |
280 |
p[i] = p[j]; |
281 |
p[j] = temp; |
282 |
} |
283 |
} |
284 |
|
285 |
/* Perform an RSA public key encryption operation */ |
286 |
static void |
287 |
sec_rsa_encrypt(uint8 * out, uint8 * in, int len, uint8 * modulus, uint8 * exponent) |
288 |
{ |
289 |
BN_CTX *ctx; |
290 |
BIGNUM mod, exp, x, y; |
291 |
uint8 inr[SEC_MODULUS_SIZE]; |
292 |
int outlen; |
293 |
|
294 |
reverse(modulus, SEC_MODULUS_SIZE); |
295 |
reverse(exponent, SEC_EXPONENT_SIZE); |
296 |
memcpy(inr, in, len); |
297 |
reverse(inr, len); |
298 |
|
299 |
ctx = BN_CTX_new(); |
300 |
BN_init(&mod); |
301 |
BN_init(&exp); |
302 |
BN_init(&x); |
303 |
BN_init(&y); |
304 |
|
305 |
BN_bin2bn(modulus, SEC_MODULUS_SIZE, &mod); |
306 |
BN_bin2bn(exponent, SEC_EXPONENT_SIZE, &exp); |
307 |
BN_bin2bn(inr, len, &x); |
308 |
BN_mod_exp(&y, &x, &exp, &mod, ctx); |
309 |
outlen = BN_bn2bin(&y, out); |
310 |
reverse(out, outlen); |
311 |
if (outlen < SEC_MODULUS_SIZE) |
312 |
memset(out + outlen, 0, SEC_MODULUS_SIZE - outlen); |
313 |
|
314 |
BN_free(&y); |
315 |
BN_clear_free(&x); |
316 |
BN_free(&exp); |
317 |
BN_free(&mod); |
318 |
BN_CTX_free(ctx); |
319 |
} |
320 |
|
321 |
/* Initialise secure transport packet */ |
322 |
STREAM |
323 |
sec_init(uint32 flags, int maxlen) |
324 |
{ |
325 |
int hdrlen; |
326 |
STREAM s; |
327 |
|
328 |
if (!licence_issued) |
329 |
hdrlen = (flags & SEC_ENCRYPT) ? 12 : 4; |
330 |
else |
331 |
hdrlen = (flags & SEC_ENCRYPT) ? 12 : 0; |
332 |
s = mcs_init(maxlen + hdrlen); |
333 |
s_push_layer(s, sec_hdr, hdrlen); |
334 |
|
335 |
return s; |
336 |
} |
337 |
|
338 |
/* Transmit secure transport packet */ |
339 |
void |
340 |
sec_send(STREAM s, uint32 flags) |
341 |
{ |
342 |
int datalen; |
343 |
|
344 |
s_pop_layer(s, sec_hdr); |
345 |
if (!licence_issued || (flags & SEC_ENCRYPT)) |
346 |
out_uint32_le(s, flags); |
347 |
|
348 |
if (flags & SEC_ENCRYPT) |
349 |
{ |
350 |
flags &= ~SEC_ENCRYPT; |
351 |
datalen = s->end - s->p - 8; |
352 |
|
353 |
#if WITH_DEBUG |
354 |
DEBUG(("Sending encrypted packet:\n")); |
355 |
hexdump(s->p + 8, datalen); |
356 |
#endif |
357 |
|
358 |
sec_sign(s->p, 8, sec_sign_key, rc4_key_len, s->p + 8, datalen); |
359 |
sec_encrypt(s->p + 8, datalen); |
360 |
} |
361 |
|
362 |
mcs_send(s); |
363 |
} |
364 |
|
365 |
/* Transfer the client random to the server */ |
366 |
static void |
367 |
sec_establish_key(void) |
368 |
{ |
369 |
uint32 length = SEC_MODULUS_SIZE + SEC_PADDING_SIZE; |
370 |
uint32 flags = SEC_CLIENT_RANDOM; |
371 |
STREAM s; |
372 |
|
373 |
s = sec_init(flags, 76); |
374 |
|
375 |
out_uint32_le(s, length); |
376 |
out_uint8p(s, sec_crypted_random, SEC_MODULUS_SIZE); |
377 |
out_uint8s(s, SEC_PADDING_SIZE); |
378 |
|
379 |
s_mark_end(s); |
380 |
sec_send(s, flags); |
381 |
} |
382 |
|
383 |
/* Output connect initial data blob */ |
384 |
static void |
385 |
sec_out_mcs_data(STREAM s) |
386 |
{ |
387 |
int hostlen = 2 * strlen(hostname); |
388 |
|
389 |
if (hostlen > 30) |
390 |
hostlen = 30; |
391 |
|
392 |
out_uint16_be(s, 5); /* unknown */ |
393 |
out_uint16_be(s, 0x14); |
394 |
out_uint8(s, 0x7c); |
395 |
out_uint16_be(s, 1); |
396 |
|
397 |
out_uint16_be(s, (158 | 0x8000)); /* remaining length */ |
398 |
|
399 |
out_uint16_be(s, 8); /* length? */ |
400 |
out_uint16_be(s, 16); |
401 |
out_uint8(s, 0); |
402 |
out_uint16_le(s, 0xc001); |
403 |
out_uint8(s, 0); |
404 |
|
405 |
out_uint32_le(s, 0x61637544); /* "Duca" ?! */ |
406 |
out_uint16_be(s, (144 | 0x8000)); /* remaining length */ |
407 |
|
408 |
/* Client information */ |
409 |
out_uint16_le(s, SEC_TAG_CLI_INFO); |
410 |
out_uint16_le(s, 136); /* length */ |
411 |
out_uint16_le(s, 1); |
412 |
out_uint16_le(s, 8); |
413 |
out_uint16_le(s, width); |
414 |
out_uint16_le(s, height); |
415 |
out_uint16_le(s, 0xca01); |
416 |
out_uint16_le(s, 0xaa03); |
417 |
out_uint32_le(s, keylayout); |
418 |
out_uint32_le(s, 419); /* client build? we are 419 compatible :-) */ |
419 |
|
420 |
/* Unicode name of client, padded to 32 bytes */ |
421 |
rdp_out_unistr(s, hostname, hostlen); |
422 |
out_uint8s(s, 30 - hostlen); |
423 |
|
424 |
out_uint32_le(s, 4); |
425 |
out_uint32(s, 0); |
426 |
out_uint32_le(s, 12); |
427 |
out_uint8s(s, 64); /* reserved? 4 + 12 doublewords */ |
428 |
|
429 |
switch (server_bpp) |
430 |
{ |
431 |
case 8: |
432 |
out_uint16_le(s, 0xca01); |
433 |
break; |
434 |
case 15: |
435 |
out_uint16_le(s, 0xca02); |
436 |
break; |
437 |
case 16: |
438 |
out_uint16_le(s, 0xca03); |
439 |
break; |
440 |
case 24: |
441 |
out_uint16_le(s, 0xca04); |
442 |
break; |
443 |
} |
444 |
out_uint16(s, 0); |
445 |
|
446 |
/* Client encryption settings */ |
447 |
out_uint16_le(s, SEC_TAG_CLI_CRYPT); |
448 |
out_uint16_le(s, 8); /* length */ |
449 |
out_uint32_le(s, encryption ? 0x3 : 0); /* encryption supported, 128-bit supported */ |
450 |
s_mark_end(s); |
451 |
} |
452 |
|
453 |
/* Parse a public key structure */ |
454 |
static BOOL |
455 |
sec_parse_public_key(STREAM s, uint8 ** modulus, uint8 ** exponent) |
456 |
{ |
457 |
uint32 magic, modulus_len; |
458 |
|
459 |
in_uint32_le(s, magic); |
460 |
if (magic != SEC_RSA_MAGIC) |
461 |
{ |
462 |
error("RSA magic 0x%x\n", magic); |
463 |
return False; |
464 |
} |
465 |
|
466 |
in_uint32_le(s, modulus_len); |
467 |
if (modulus_len != SEC_MODULUS_SIZE + SEC_PADDING_SIZE) |
468 |
{ |
469 |
error("modulus len 0x%x\n", modulus_len); |
470 |
return False; |
471 |
} |
472 |
|
473 |
in_uint8s(s, 8); /* modulus_bits, unknown */ |
474 |
in_uint8p(s, *exponent, SEC_EXPONENT_SIZE); |
475 |
in_uint8p(s, *modulus, SEC_MODULUS_SIZE); |
476 |
in_uint8s(s, SEC_PADDING_SIZE); |
477 |
|
478 |
return s_check(s); |
479 |
} |
480 |
|
481 |
/* Parse a crypto information structure */ |
482 |
static BOOL |
483 |
sec_parse_crypt_info(STREAM s, uint32 * rc4_key_size, |
484 |
uint8 ** server_random, uint8 ** modulus, uint8 ** exponent) |
485 |
{ |
486 |
uint32 crypt_level, random_len, rsa_info_len; |
487 |
uint16 tag, length; |
488 |
uint8 *next_tag, *end; |
489 |
|
490 |
in_uint32_le(s, *rc4_key_size); /* 1 = 40-bit, 2 = 128-bit */ |
491 |
in_uint32_le(s, crypt_level); /* 1 = low, 2 = medium, 3 = high */ |
492 |
if (crypt_level == 0) /* no encryptation */ |
493 |
return False; |
494 |
in_uint32_le(s, random_len); |
495 |
in_uint32_le(s, rsa_info_len); |
496 |
|
497 |
if (random_len != SEC_RANDOM_SIZE) |
498 |
{ |
499 |
error("random len %d\n", random_len); |
500 |
return False; |
501 |
} |
502 |
|
503 |
in_uint8p(s, *server_random, random_len); |
504 |
|
505 |
/* RSA info */ |
506 |
end = s->p + rsa_info_len; |
507 |
if (end > s->end) |
508 |
return False; |
509 |
|
510 |
in_uint8s(s, 12); /* unknown */ |
511 |
|
512 |
while (s->p < end) |
513 |
{ |
514 |
in_uint16_le(s, tag); |
515 |
in_uint16_le(s, length); |
516 |
|
517 |
next_tag = s->p + length; |
518 |
|
519 |
switch (tag) |
520 |
{ |
521 |
case SEC_TAG_PUBKEY: |
522 |
if (!sec_parse_public_key(s, modulus, exponent)) |
523 |
return False; |
524 |
|
525 |
break; |
526 |
|
527 |
case SEC_TAG_KEYSIG: |
528 |
/* Is this a Microsoft key that we just got? */ |
529 |
/* Care factor: zero! */ |
530 |
break; |
531 |
|
532 |
default: |
533 |
unimpl("crypt tag 0x%x\n", tag); |
534 |
} |
535 |
|
536 |
s->p = next_tag; |
537 |
} |
538 |
|
539 |
return s_check_end(s); |
540 |
} |
541 |
|
542 |
/* Process crypto information blob */ |
543 |
static void |
544 |
sec_process_crypt_info(STREAM s) |
545 |
{ |
546 |
uint8 *server_random, *modulus, *exponent; |
547 |
uint8 client_random[SEC_RANDOM_SIZE]; |
548 |
uint32 rc4_key_size; |
549 |
|
550 |
if (!sec_parse_crypt_info(s, &rc4_key_size, &server_random, &modulus, &exponent)) |
551 |
return; |
552 |
|
553 |
/* Generate a client random, and hence determine encryption keys */ |
554 |
generate_random(client_random); |
555 |
sec_rsa_encrypt(sec_crypted_random, client_random, SEC_RANDOM_SIZE, modulus, exponent); |
556 |
sec_generate_keys(client_random, server_random, rc4_key_size); |
557 |
} |
558 |
|
559 |
/* Process connect response data blob */ |
560 |
static void |
561 |
sec_process_mcs_data(STREAM s) |
562 |
{ |
563 |
uint16 tag, length; |
564 |
uint8 *next_tag; |
565 |
uint8 len; |
566 |
|
567 |
in_uint8s(s, 21); /* header */ |
568 |
in_uint8(s, len); |
569 |
if (len & 0x80) |
570 |
in_uint8(s, len); |
571 |
|
572 |
while (s->p < s->end) |
573 |
{ |
574 |
in_uint16_le(s, tag); |
575 |
in_uint16_le(s, length); |
576 |
|
577 |
if (length <= 4) |
578 |
return; |
579 |
|
580 |
next_tag = s->p + length - 4; |
581 |
|
582 |
switch (tag) |
583 |
{ |
584 |
case SEC_TAG_SRV_INFO: |
585 |
case SEC_TAG_SRV_3: |
586 |
break; |
587 |
|
588 |
case SEC_TAG_SRV_CRYPT: |
589 |
sec_process_crypt_info(s); |
590 |
break; |
591 |
|
592 |
default: |
593 |
unimpl("response tag 0x%x\n", tag); |
594 |
} |
595 |
|
596 |
s->p = next_tag; |
597 |
} |
598 |
} |
599 |
|
600 |
/* Receive secure transport packet */ |
601 |
STREAM |
602 |
sec_recv(void) |
603 |
{ |
604 |
uint32 sec_flags; |
605 |
STREAM s; |
606 |
|
607 |
while ((s = mcs_recv()) != NULL) |
608 |
{ |
609 |
if (encryption || !licence_issued) |
610 |
{ |
611 |
in_uint32_le(s, sec_flags); |
612 |
|
613 |
if (sec_flags & SEC_LICENCE_NEG) |
614 |
{ |
615 |
licence_process(s); |
616 |
continue; |
617 |
} |
618 |
|
619 |
if (sec_flags & SEC_ENCRYPT) |
620 |
{ |
621 |
in_uint8s(s, 8); /* signature */ |
622 |
sec_decrypt(s->p, s->end - s->p); |
623 |
} |
624 |
} |
625 |
|
626 |
return s; |
627 |
} |
628 |
|
629 |
return NULL; |
630 |
} |
631 |
|
632 |
/* Establish a secure connection */ |
633 |
BOOL |
634 |
sec_connect(char *server) |
635 |
{ |
636 |
struct stream mcs_data; |
637 |
|
638 |
/* We exchange some RDP data during the MCS-Connect */ |
639 |
mcs_data.size = 512; |
640 |
mcs_data.p = mcs_data.data = xmalloc(mcs_data.size); |
641 |
sec_out_mcs_data(&mcs_data); |
642 |
|
643 |
if (!mcs_connect(server, &mcs_data)) |
644 |
return False; |
645 |
|
646 |
sec_process_mcs_data(&mcs_data); |
647 |
if (encryption) |
648 |
sec_establish_key(); |
649 |
xfree(mcs_data.data); |
650 |
return True; |
651 |
} |
652 |
|
653 |
/* Disconnect a connection */ |
654 |
void |
655 |
sec_disconnect(void) |
656 |
{ |
657 |
mcs_disconnect(); |
658 |
} |