1 |
/* |
/* -*- c-basic-offset: 8 -*- |
2 |
rdesktop: A Remote Desktop Protocol client. |
rdesktop: A Remote Desktop Protocol client. |
3 |
Protocol services - RDP encryption and licensing |
Protocol services - RDP encryption and licensing |
4 |
Copyright (C) Matthew Chapman 1999-2001 |
Copyright (C) Matthew Chapman 1999-2002 |
5 |
|
|
6 |
This program is free software; you can redistribute it and/or modify |
This program is free software; you can redistribute it and/or modify |
7 |
it under the terms of the GNU General Public License as published by |
it under the terms of the GNU General Public License as published by |
25 |
#include <openssl/md5.h> |
#include <openssl/md5.h> |
26 |
#include <openssl/sha.h> |
#include <openssl/sha.h> |
27 |
#include <openssl/bn.h> |
#include <openssl/bn.h> |
28 |
|
#include <openssl/x509v3.h> |
29 |
#else |
#else |
30 |
#include "crypto/rc4.h" |
#include "crypto/rc4.h" |
31 |
#include "crypto/md5.h" |
#include "crypto/md5.h" |
38 |
extern int height; |
extern int height; |
39 |
extern int keylayout; |
extern int keylayout; |
40 |
extern BOOL encryption; |
extern BOOL encryption; |
41 |
extern BOOL licence_issued; |
extern BOOL g_licence_issued; |
42 |
|
extern BOOL use_rdp5; |
43 |
|
extern int server_bpp; |
44 |
|
|
45 |
static int rc4_key_len; |
static int rc4_key_len; |
46 |
static RC4_KEY rc4_decrypt_key; |
static RC4_KEY rc4_decrypt_key; |
47 |
static RC4_KEY rc4_encrypt_key; |
static RC4_KEY rc4_encrypt_key; |
48 |
|
static RSA *server_public_key; |
49 |
|
|
50 |
static uint8 sec_sign_key[16]; |
static uint8 sec_sign_key[16]; |
51 |
static uint8 sec_decrypt_key[16]; |
static uint8 sec_decrypt_key[16]; |
54 |
static uint8 sec_encrypt_update_key[16]; |
static uint8 sec_encrypt_update_key[16]; |
55 |
static uint8 sec_crypted_random[SEC_MODULUS_SIZE]; |
static uint8 sec_crypted_random[SEC_MODULUS_SIZE]; |
56 |
|
|
57 |
|
uint16 server_rdp_version = 0; |
58 |
|
|
59 |
/* |
/* |
60 |
* General purpose 48-byte transformation, using two 32-byte salts (generally, |
* General purpose 48-byte transformation, using two 32-byte salts (generally, |
61 |
* a client and server salt) and a global salt value used for padding. |
* a client and server salt) and a global salt value used for padding. |
133 |
memcpy(sec_sign_key, session_key, 16); |
memcpy(sec_sign_key, session_key, 16); |
134 |
|
|
135 |
/* Generate RC4 keys */ |
/* Generate RC4 keys */ |
136 |
sec_hash_16(sec_decrypt_key, &session_key[16], client_key, |
sec_hash_16(sec_decrypt_key, &session_key[16], client_key, server_key); |
137 |
server_key); |
sec_hash_16(sec_encrypt_key, &session_key[32], client_key, server_key); |
|
sec_hash_16(sec_encrypt_key, &session_key[32], client_key, |
|
|
server_key); |
|
138 |
|
|
139 |
if (rc4_key_size == 1) |
if (rc4_key_size == 1) |
140 |
{ |
{ |
146 |
} |
} |
147 |
else |
else |
148 |
{ |
{ |
149 |
DEBUG(("128-bit encryption enabled\n")); |
DEBUG(("rc_4_key_size == %d, 128-bit encryption enabled\n", rc4_key_size)); |
150 |
rc4_key_len = 16; |
rc4_key_len = 16; |
151 |
} |
} |
152 |
|
|
185 |
|
|
186 |
/* Generate a signature hash, using a combination of SHA1 and MD5 */ |
/* Generate a signature hash, using a combination of SHA1 and MD5 */ |
187 |
void |
void |
188 |
sec_sign(uint8 * signature, int siglen, uint8 * session_key, int keylen, |
sec_sign(uint8 * signature, int siglen, uint8 * session_key, int keylen, uint8 * data, int datalen) |
|
uint8 * data, int datalen) |
|
189 |
{ |
{ |
190 |
uint8 shasig[20]; |
uint8 shasig[20]; |
191 |
uint8 md5sig[16]; |
uint8 md5sig[16]; |
257 |
} |
} |
258 |
|
|
259 |
/* Decrypt data using RC4 */ |
/* Decrypt data using RC4 */ |
260 |
static void |
void |
261 |
sec_decrypt(uint8 * data, int length) |
sec_decrypt(uint8 * data, int length) |
262 |
{ |
{ |
263 |
static int use_count; |
static int use_count; |
289 |
|
|
290 |
/* Perform an RSA public key encryption operation */ |
/* Perform an RSA public key encryption operation */ |
291 |
static void |
static void |
292 |
sec_rsa_encrypt(uint8 * out, uint8 * in, int len, |
sec_rsa_encrypt(uint8 * out, uint8 * in, int len, uint8 * modulus, uint8 * exponent) |
|
uint8 * modulus, uint8 * exponent) |
|
293 |
{ |
{ |
294 |
BN_CTX ctx; |
BN_CTX *ctx; |
295 |
BIGNUM mod, exp, x, y; |
BIGNUM mod, exp, x, y; |
296 |
uint8 inr[SEC_MODULUS_SIZE]; |
uint8 inr[SEC_MODULUS_SIZE]; |
297 |
int outlen; |
int outlen; |
301 |
memcpy(inr, in, len); |
memcpy(inr, in, len); |
302 |
reverse(inr, len); |
reverse(inr, len); |
303 |
|
|
304 |
BN_CTX_init(&ctx); |
ctx = BN_CTX_new(); |
305 |
BN_init(&mod); |
BN_init(&mod); |
306 |
BN_init(&exp); |
BN_init(&exp); |
307 |
BN_init(&x); |
BN_init(&x); |
310 |
BN_bin2bn(modulus, SEC_MODULUS_SIZE, &mod); |
BN_bin2bn(modulus, SEC_MODULUS_SIZE, &mod); |
311 |
BN_bin2bn(exponent, SEC_EXPONENT_SIZE, &exp); |
BN_bin2bn(exponent, SEC_EXPONENT_SIZE, &exp); |
312 |
BN_bin2bn(inr, len, &x); |
BN_bin2bn(inr, len, &x); |
313 |
BN_mod_exp(&y, &x, &exp, &mod, &ctx); |
BN_mod_exp(&y, &x, &exp, &mod, ctx); |
314 |
outlen = BN_bn2bin(&y, out); |
outlen = BN_bn2bin(&y, out); |
315 |
reverse(out, outlen); |
reverse(out, outlen); |
316 |
if (outlen < SEC_MODULUS_SIZE) |
if (outlen < SEC_MODULUS_SIZE) |
320 |
BN_clear_free(&x); |
BN_clear_free(&x); |
321 |
BN_free(&exp); |
BN_free(&exp); |
322 |
BN_free(&mod); |
BN_free(&mod); |
323 |
BN_CTX_free(&ctx); |
BN_CTX_free(ctx); |
324 |
} |
} |
325 |
|
|
326 |
/* Initialise secure transport packet */ |
/* Initialise secure transport packet */ |
330 |
int hdrlen; |
int hdrlen; |
331 |
STREAM s; |
STREAM s; |
332 |
|
|
333 |
if (!licence_issued) |
if (!g_licence_issued) |
334 |
hdrlen = (flags & SEC_ENCRYPT) ? 12 : 4; |
hdrlen = (flags & SEC_ENCRYPT) ? 12 : 4; |
335 |
else |
else |
336 |
hdrlen = (flags & SEC_ENCRYPT) ? 12 : 0; |
hdrlen = (flags & SEC_ENCRYPT) ? 12 : 0; |
347 |
int datalen; |
int datalen; |
348 |
|
|
349 |
s_pop_layer(s, sec_hdr); |
s_pop_layer(s, sec_hdr); |
350 |
if (!licence_issued || (flags & SEC_ENCRYPT)) |
if (!g_licence_issued || (flags & SEC_ENCRYPT)) |
351 |
out_uint32_le(s, flags); |
out_uint32_le(s, flags); |
352 |
|
|
353 |
if (flags & SEC_ENCRYPT) |
if (flags & SEC_ENCRYPT) |
360 |
hexdump(s->p + 8, datalen); |
hexdump(s->p + 8, datalen); |
361 |
#endif |
#endif |
362 |
|
|
363 |
sec_sign(s->p, 8, sec_sign_key, rc4_key_len, s->p + 8, |
sec_sign(s->p, 8, sec_sign_key, rc4_key_len, s->p + 8, datalen); |
|
datalen); |
|
364 |
sec_encrypt(s->p + 8, datalen); |
sec_encrypt(s->p + 8, datalen); |
365 |
} |
} |
366 |
|
|
369 |
|
|
370 |
/* Transfer the client random to the server */ |
/* Transfer the client random to the server */ |
371 |
static void |
static void |
372 |
sec_establish_key() |
sec_establish_key(void) |
373 |
{ |
{ |
374 |
uint32 length = SEC_MODULUS_SIZE + SEC_PADDING_SIZE; |
uint32 length = SEC_MODULUS_SIZE + SEC_PADDING_SIZE; |
375 |
uint32 flags = SEC_CLIENT_RANDOM; |
uint32 flags = SEC_CLIENT_RANDOM; |
390 |
sec_out_mcs_data(STREAM s) |
sec_out_mcs_data(STREAM s) |
391 |
{ |
{ |
392 |
int hostlen = 2 * strlen(hostname); |
int hostlen = 2 * strlen(hostname); |
393 |
|
int length = 158 + 76 + 12 + 4 + 20; |
394 |
|
|
395 |
|
if (hostlen > 30) |
396 |
|
hostlen = 30; |
397 |
|
|
398 |
out_uint16_be(s, 5); /* unknown */ |
out_uint16_be(s, 5); /* unknown */ |
399 |
out_uint16_be(s, 0x14); |
out_uint16_be(s, 0x14); |
400 |
out_uint8(s, 0x7c); |
out_uint8(s, 0x7c); |
401 |
out_uint16_be(s, 1); |
out_uint16_be(s, 1); |
402 |
|
|
403 |
out_uint16_be(s, (158 | 0x8000)); /* remaining length */ |
out_uint16_be(s, (length | 0x8000)); /* remaining length */ |
404 |
|
|
405 |
out_uint16_be(s, 8); /* length? */ |
out_uint16_be(s, 8); /* length? */ |
406 |
out_uint16_be(s, 16); |
out_uint16_be(s, 16); |
409 |
out_uint8(s, 0); |
out_uint8(s, 0); |
410 |
|
|
411 |
out_uint32_le(s, 0x61637544); /* "Duca" ?! */ |
out_uint32_le(s, 0x61637544); /* "Duca" ?! */ |
412 |
out_uint16_be(s, (144 | 0x8000)); /* remaining length */ |
out_uint16_be(s, ((length - 14) | 0x8000)); /* remaining length */ |
413 |
|
|
414 |
/* Client information */ |
/* Client information */ |
415 |
out_uint16_le(s, SEC_TAG_CLI_INFO); |
out_uint16_le(s, SEC_TAG_CLI_INFO); |
416 |
out_uint16_le(s, 136); /* length */ |
out_uint16_le(s, 212); /* length */ |
417 |
out_uint16_le(s, 1); |
out_uint16_le(s, use_rdp5 ? 4 : 1); /* RDP version. 1 == RDP4, 4 == RDP5. */ |
418 |
out_uint16_le(s, 8); |
out_uint16_le(s, 8); |
419 |
out_uint16_le(s, width); |
out_uint16_le(s, width); |
420 |
out_uint16_le(s, height); |
out_uint16_le(s, height); |
421 |
out_uint16_le(s, 0xca01); |
out_uint16_le(s, 0xca01); |
422 |
out_uint16_le(s, 0xaa03); |
out_uint16_le(s, 0xaa03); |
423 |
out_uint32_le(s, keylayout); |
out_uint32_le(s, keylayout); |
424 |
out_uint32_le(s, 419); /* client build? we are 419 compatible :-) */ |
out_uint32_le(s, 2600); /* Client build. We are now 2600 compatible :-) */ |
425 |
|
|
426 |
/* Unicode name of client, padded to 32 bytes */ |
/* Unicode name of client, padded to 32 bytes */ |
427 |
rdp_out_unistr(s, hostname, hostlen); |
rdp_out_unistr(s, hostname, hostlen); |
432 |
out_uint32_le(s, 12); |
out_uint32_le(s, 12); |
433 |
out_uint8s(s, 64); /* reserved? 4 + 12 doublewords */ |
out_uint8s(s, 64); /* reserved? 4 + 12 doublewords */ |
434 |
|
|
435 |
out_uint16(s, 0xca01); |
switch (server_bpp) |
436 |
out_uint16(s, 0); |
{ |
437 |
|
case 8: |
438 |
|
out_uint16_le(s, 0xca01); |
439 |
|
break; |
440 |
|
case 15: |
441 |
|
out_uint16_le(s, 0xca02); |
442 |
|
break; |
443 |
|
case 16: |
444 |
|
out_uint16_le(s, 0xca03); |
445 |
|
break; |
446 |
|
case 24: |
447 |
|
out_uint16_le(s, 0xca04); |
448 |
|
break; |
449 |
|
} |
450 |
|
out_uint16_le(s, 1); |
451 |
|
|
452 |
|
out_uint32(s, 0); |
453 |
|
out_uint8(s, server_bpp); |
454 |
|
out_uint16_le(s, 0x0700); |
455 |
|
out_uint8(s, 0); |
456 |
|
out_uint32_le(s, 1); |
457 |
|
out_uint8s(s, 64); /* End of client info */ |
458 |
|
|
459 |
|
out_uint16_le(s, SEC_TAG_CLI_4); |
460 |
|
out_uint16_le(s, 12); |
461 |
|
out_uint32_le(s, 9); |
462 |
|
out_uint32(s, 0); |
463 |
|
|
464 |
/* Client encryption settings */ |
/* Client encryption settings */ |
465 |
out_uint16_le(s, SEC_TAG_CLI_CRYPT); |
out_uint16_le(s, SEC_TAG_CLI_CRYPT); |
466 |
out_uint16(s, 8); /* length */ |
out_uint16_le(s, 12); /* length */ |
467 |
out_uint32_le(s, encryption ? 0x3 : 0); /* encryption supported, 128-bit supported */ |
out_uint32_le(s, encryption ? 0x3 : 0); /* encryption supported, 128-bit supported */ |
468 |
|
out_uint32(s, 0); /* Unknown */ |
469 |
|
|
470 |
|
out_uint16_le(s, SEC_TAG_CLI_CHANNELS); |
471 |
|
out_uint16_le(s, 20); /* length */ |
472 |
|
out_uint32_le(s, 1); /* number of virtual channels */ |
473 |
|
out_uint8p(s, "cliprdr", 8); /* name padded to 8(?) */ |
474 |
|
out_uint16(s, 0); |
475 |
|
out_uint16_le(s, 0xc0a0); /* Flags. Rumours tell this is documented in MSDN. */ |
476 |
|
|
477 |
s_mark_end(s); |
s_mark_end(s); |
478 |
} |
} |
479 |
|
|
505 |
return s_check(s); |
return s_check(s); |
506 |
} |
} |
507 |
|
|
508 |
|
static BOOL |
509 |
|
sec_parse_x509_key(X509 * cert) |
510 |
|
{ |
511 |
|
EVP_PKEY *epk = NULL; |
512 |
|
/* By some reason, Microsoft sets the OID of the Public RSA key to |
513 |
|
the oid for "MD5 with RSA Encryption" instead of "RSA Encryption" |
514 |
|
|
515 |
|
Kudos to Richard Levitte for the following (. intiutive .) |
516 |
|
lines of code that resets the OID and let's us extract the key. */ |
517 |
|
if (OBJ_obj2nid(cert->cert_info->key->algor->algorithm) == NID_md5WithRSAEncryption) |
518 |
|
{ |
519 |
|
DEBUG_RDP5(("Re-setting algorithm type to RSA in server certificate\n")); |
520 |
|
cert->cert_info->key->algor->algorithm = OBJ_nid2obj(NID_rsaEncryption); |
521 |
|
} |
522 |
|
epk = X509_get_pubkey(cert); |
523 |
|
if (NULL == epk) |
524 |
|
{ |
525 |
|
error("Failed to extract public key from certificate\n"); |
526 |
|
return False; |
527 |
|
} |
528 |
|
|
529 |
|
server_public_key = (RSA *) epk->pkey.ptr; |
530 |
|
|
531 |
|
return True; |
532 |
|
} |
533 |
|
|
534 |
|
|
535 |
/* Parse a crypto information structure */ |
/* Parse a crypto information structure */ |
536 |
static BOOL |
static BOOL |
537 |
sec_parse_crypt_info(STREAM s, uint32 * rc4_key_size, |
sec_parse_crypt_info(STREAM s, uint32 * rc4_key_size, |
538 |
uint8 ** server_random, uint8 ** modulus, |
uint8 ** server_random, uint8 ** modulus, uint8 ** exponent) |
|
uint8 ** exponent) |
|
539 |
{ |
{ |
540 |
uint32 crypt_level, random_len, rsa_info_len; |
uint32 crypt_level, random_len, rsa_info_len; |
541 |
|
uint32 cacert_len, cert_len, flags; |
542 |
|
X509 *cacert, *server_cert; |
543 |
uint16 tag, length; |
uint16 tag, length; |
544 |
uint8 *next_tag, *end; |
uint8 *next_tag, *end; |
545 |
|
|
546 |
in_uint32_le(s, *rc4_key_size); /* 1 = 40-bit, 2 = 128-bit */ |
in_uint32_le(s, *rc4_key_size); /* 1 = 40-bit, 2 = 128-bit */ |
547 |
in_uint32_le(s, crypt_level); /* 1 = low, 2 = medium, 3 = high */ |
in_uint32_le(s, crypt_level); /* 1 = low, 2 = medium, 3 = high */ |
548 |
|
if (crypt_level == 0) /* no encryption */ |
549 |
|
return False; |
550 |
in_uint32_le(s, random_len); |
in_uint32_le(s, random_len); |
551 |
in_uint32_le(s, rsa_info_len); |
in_uint32_le(s, rsa_info_len); |
552 |
|
|
553 |
if (random_len != SEC_RANDOM_SIZE) |
if (random_len != SEC_RANDOM_SIZE) |
554 |
{ |
{ |
555 |
error("random len %d\n", random_len); |
error("random len %d, expected %d\n", random_len, SEC_RANDOM_SIZE); |
556 |
return False; |
return False; |
557 |
} |
} |
558 |
|
|
563 |
if (end > s->end) |
if (end > s->end) |
564 |
return False; |
return False; |
565 |
|
|
566 |
in_uint8s(s, 12); /* unknown */ |
in_uint32_le(s, flags); /* 1 = RDP4-style, 0x80000002 = X.509 */ |
567 |
|
if (flags & 1) |
568 |
|
{ |
569 |
|
DEBUG_RDP5(("We're going for the RDP4-style encryption\n")); |
570 |
|
in_uint8s(s, 8); /* unknown */ |
571 |
|
|
572 |
|
while (s->p < end) |
573 |
|
{ |
574 |
|
in_uint16_le(s, tag); |
575 |
|
in_uint16_le(s, length); |
576 |
|
|
577 |
|
next_tag = s->p + length; |
578 |
|
|
579 |
|
switch (tag) |
580 |
|
{ |
581 |
|
case SEC_TAG_PUBKEY: |
582 |
|
if (!sec_parse_public_key(s, modulus, exponent)) |
583 |
|
return False; |
584 |
|
DEBUG_RDP5(("Got Public key, RDP4-style\n")); |
585 |
|
|
586 |
|
break; |
587 |
|
|
588 |
|
case SEC_TAG_KEYSIG: |
589 |
|
/* Is this a Microsoft key that we just got? */ |
590 |
|
/* Care factor: zero! */ |
591 |
|
/* Actually, it would probably be a good idea to check if the public key is signed with this key, and then store this |
592 |
|
key as a known key of the hostname. This would prevent some MITM-attacks. */ |
593 |
|
break; |
594 |
|
|
595 |
|
default: |
596 |
|
unimpl("crypt tag 0x%x\n", tag); |
597 |
|
} |
598 |
|
|
599 |
while (s->p < end) |
s->p = next_tag; |
600 |
|
} |
601 |
|
} |
602 |
|
else |
603 |
{ |
{ |
604 |
in_uint16_le(s, tag); |
DEBUG_RDP5(("We're going for the RDP5-style encryption\n")); |
605 |
in_uint16_le(s, length); |
in_uint8s(s, 4); /* Number of certificates */ |
606 |
|
|
607 |
next_tag = s->p + length; |
/* Do da funky X.509 stuffy |
608 |
|
|
609 |
switch (tag) |
"How did I find out about this? I looked up and saw a |
610 |
|
bright light and when I came to I had a scar on my forehead |
611 |
|
and knew about X.500" |
612 |
|
- Peter Gutman in a early version of |
613 |
|
http://www.cs.auckland.ac.nz/~pgut001/pubs/x509guide.txt |
614 |
|
*/ |
615 |
|
|
616 |
|
in_uint32_le(s, cacert_len); |
617 |
|
cacert = d2i_X509(NULL, &(s->p), cacert_len); |
618 |
|
/* Note: We don't need to move s->p here - d2i_X509 is |
619 |
|
"kind" enough to do it for us */ |
620 |
|
if (NULL == cacert) |
621 |
{ |
{ |
622 |
case SEC_TAG_PUBKEY: |
error("Couldn't load CA Certificate from server\n"); |
623 |
if (!sec_parse_public_key |
return False; |
624 |
(s, modulus, exponent)) |
} |
|
return False; |
|
625 |
|
|
626 |
break; |
/* Currently, we don't use the CA Certificate. |
627 |
|
FIXME: |
628 |
|
*) Verify the server certificate (server_cert) with the |
629 |
|
CA certificate. |
630 |
|
*) Store the CA Certificate with the hostname of the |
631 |
|
server we are connecting to as key, and compare it |
632 |
|
when we connect the next time, in order to prevent |
633 |
|
MITM-attacks. |
634 |
|
*/ |
635 |
|
|
636 |
|
in_uint32_le(s, cert_len); |
637 |
|
server_cert = d2i_X509(NULL, &(s->p), cert_len); |
638 |
|
if (NULL == server_cert) |
639 |
|
{ |
640 |
|
error("Couldn't load Certificate from server\n"); |
641 |
|
return False; |
642 |
|
} |
643 |
|
|
644 |
case SEC_TAG_KEYSIG: |
in_uint8s(s, 16); /* Padding */ |
|
/* Is this a Microsoft key that we just got? */ |
|
|
/* Care factor: zero! */ |
|
|
break; |
|
645 |
|
|
646 |
default: |
/* Note: Verifying the server certificate must be done here, |
647 |
unimpl("crypt tag 0x%x\n", tag); |
before sec_parse_public_key since we'll have to apply |
648 |
} |
serious violence to the key after this */ |
649 |
|
|
650 |
s->p = next_tag; |
if (!sec_parse_x509_key(server_cert)) |
651 |
|
{ |
652 |
|
DEBUG_RDP5(("Didn't parse X509 correctly\n")); |
653 |
|
return False; |
654 |
|
} |
655 |
|
return True; /* There's some garbage here we don't care about */ |
656 |
} |
} |
|
|
|
657 |
return s_check_end(s); |
return s_check_end(s); |
658 |
} |
} |
659 |
|
|
664 |
uint8 *server_random, *modulus, *exponent; |
uint8 *server_random, *modulus, *exponent; |
665 |
uint8 client_random[SEC_RANDOM_SIZE]; |
uint8 client_random[SEC_RANDOM_SIZE]; |
666 |
uint32 rc4_key_size; |
uint32 rc4_key_size; |
667 |
|
uint8 inr[SEC_MODULUS_SIZE]; |
668 |
|
|
669 |
if (!sec_parse_crypt_info(s, &rc4_key_size, &server_random, |
if (!sec_parse_crypt_info(s, &rc4_key_size, &server_random, &modulus, &exponent)) |
670 |
&modulus, &exponent)) |
{ |
671 |
|
DEBUG(("Failed to parse crypt info\n")); |
672 |
return; |
return; |
673 |
|
} |
674 |
|
|
675 |
|
DEBUG(("Generating client random\n")); |
676 |
|
// This is what the MS client do: |
677 |
|
memset(inr, 0, SEC_RANDOM_SIZE); |
678 |
|
/* *ARIGL!* Plaintext attack, anyone? |
679 |
|
I tried doing: |
680 |
|
generate_random(inr); |
681 |
|
..but that generates connection errors now and then (yes, |
682 |
|
"now and then". Something like 0 to 3 attempts needed before a |
683 |
|
successful connection. Nice. Not! |
684 |
|
*/ |
685 |
|
|
|
/* Generate a client random, and hence determine encryption keys */ |
|
686 |
generate_random(client_random); |
generate_random(client_random); |
687 |
sec_rsa_encrypt(sec_crypted_random, client_random, |
if (NULL != server_public_key) |
688 |
SEC_RANDOM_SIZE, modulus, exponent); |
{ /* Which means we should use |
689 |
|
RDP5-style encryption */ |
690 |
|
|
691 |
|
memcpy(inr + SEC_RANDOM_SIZE, client_random, SEC_RANDOM_SIZE); |
692 |
|
reverse(inr + SEC_RANDOM_SIZE, SEC_RANDOM_SIZE); |
693 |
|
|
694 |
|
RSA_public_encrypt(SEC_MODULUS_SIZE, |
695 |
|
inr, sec_crypted_random, server_public_key, RSA_NO_PADDING); |
696 |
|
|
697 |
|
reverse(sec_crypted_random, SEC_MODULUS_SIZE); |
698 |
|
|
699 |
|
} |
700 |
|
else |
701 |
|
{ /* RDP4-style encryption */ |
702 |
|
sec_rsa_encrypt(sec_crypted_random, |
703 |
|
client_random, SEC_RANDOM_SIZE, modulus, exponent); |
704 |
|
} |
705 |
sec_generate_keys(client_random, server_random, rc4_key_size); |
sec_generate_keys(client_random, server_random, rc4_key_size); |
706 |
} |
} |
707 |
|
|
708 |
/* Process connect response data blob */ |
|
709 |
|
/* Process SRV_INFO, find RDP version supported by server */ |
710 |
static void |
static void |
711 |
|
sec_process_srv_info(STREAM s) |
712 |
|
{ |
713 |
|
in_uint16_le(s, server_rdp_version); |
714 |
|
DEBUG_RDP5(("Server RDP version is %d\n", server_rdp_version)); |
715 |
|
} |
716 |
|
|
717 |
|
|
718 |
|
/* Process connect response data blob */ |
719 |
|
void |
720 |
sec_process_mcs_data(STREAM s) |
sec_process_mcs_data(STREAM s) |
721 |
{ |
{ |
722 |
uint16 tag, length; |
uint16 tag, length; |
723 |
uint8 *next_tag; |
uint8 *next_tag; |
724 |
|
uint8 len; |
725 |
|
|
726 |
in_uint8s(s, 23); /* header */ |
in_uint8s(s, 21); /* header (T.124 stuff, probably) */ |
727 |
|
in_uint8(s, len); |
728 |
|
if (len & 0x80) |
729 |
|
in_uint8(s, len); |
730 |
|
|
731 |
while (s->p < s->end) |
while (s->p < s->end) |
732 |
{ |
{ |
741 |
switch (tag) |
switch (tag) |
742 |
{ |
{ |
743 |
case SEC_TAG_SRV_INFO: |
case SEC_TAG_SRV_INFO: |
744 |
|
sec_process_srv_info(s); |
745 |
|
break; |
746 |
|
|
747 |
case SEC_TAG_SRV_3: |
case SEC_TAG_SRV_3: |
748 |
break; |
break; |
749 |
|
|
761 |
|
|
762 |
/* Receive secure transport packet */ |
/* Receive secure transport packet */ |
763 |
STREAM |
STREAM |
764 |
sec_recv() |
sec_recv(void) |
765 |
{ |
{ |
766 |
uint32 sec_flags; |
uint32 sec_flags; |
767 |
|
uint16 channel; |
768 |
STREAM s; |
STREAM s; |
769 |
|
|
770 |
while ((s = mcs_recv()) != NULL) |
while ((s = mcs_recv(&channel)) != NULL) |
771 |
{ |
{ |
772 |
if (encryption || !licence_issued) |
if (encryption || !g_licence_issued) |
773 |
{ |
{ |
774 |
in_uint32_le(s, sec_flags); |
in_uint32_le(s, sec_flags); |
775 |
|
|
776 |
if (sec_flags & SEC_LICENCE_NEG) |
if (sec_flags & SEC_LICENCE_NEG) |
777 |
{ |
{ |
778 |
|
if (sec_flags & SEC_ENCRYPT) { |
779 |
|
DEBUG_RDP5(("Encrypted license detected\n")); |
780 |
|
} |
781 |
licence_process(s); |
licence_process(s); |
782 |
continue; |
continue; |
783 |
} |
} |
789 |
} |
} |
790 |
} |
} |
791 |
|
|
792 |
return s; |
if (MCS_GLOBAL_CHANNEL == channel) |
793 |
|
{ |
794 |
|
return s; |
795 |
|
} |
796 |
|
else |
797 |
|
rdp5_process_channel(s, channel); |
798 |
|
|
799 |
} |
} |
800 |
|
|
801 |
return NULL; |
return NULL; |
803 |
|
|
804 |
/* Establish a secure connection */ |
/* Establish a secure connection */ |
805 |
BOOL |
BOOL |
806 |
sec_connect(char *server) |
sec_connect(char *server, char *username) |
807 |
{ |
{ |
808 |
struct stream mcs_data; |
struct stream mcs_data; |
809 |
|
|
810 |
/* We exchange some RDP data during the MCS-Connect */ |
/* We exchange some RDP data during the MCS-Connect */ |
811 |
mcs_data.size = 512; |
mcs_data.size = 512; |
812 |
mcs_data.p = mcs_data.data = xmalloc(mcs_data.size); |
mcs_data.p = mcs_data.data = (uint8*)xmalloc(mcs_data.size); |
813 |
sec_out_mcs_data(&mcs_data); |
sec_out_mcs_data(&mcs_data); |
814 |
|
|
815 |
if (!mcs_connect(server, &mcs_data)) |
if (!mcs_connect(server, &mcs_data, username)) |
816 |
return False; |
return False; |
817 |
|
|
818 |
sec_process_mcs_data(&mcs_data); |
// sec_process_mcs_data(&mcs_data); |
819 |
if (encryption) |
if (encryption) |
820 |
sec_establish_key(); |
sec_establish_key(); |
821 |
|
xfree(mcs_data.data); |
822 |
return True; |
return True; |
823 |
} |
} |
824 |
|
|
825 |
/* Disconnect a connection */ |
/* Disconnect a connection */ |
826 |
void |
void |
827 |
sec_disconnect() |
sec_disconnect(void) |
828 |
{ |
{ |
829 |
mcs_disconnect(); |
mcs_disconnect(); |
830 |
} |
} |