1 |
/* -*- c-basic-offset: 8 -*- |
/* -*- 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 1999-2005 |
Copyright (C) Matthew Chapman 1999-2007 |
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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 |
19 |
*/ |
*/ |
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#include "rdesktop.h" |
#include "rdesktop.h" |
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#include "ssl.h" |
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#include <openssl/rc4.h> |
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#include <openssl/md5.h> |
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#include <openssl/sha.h> |
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#include <openssl/bn.h> |
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#include <openssl/x509v3.h> |
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24 |
extern char g_hostname[16]; |
extern char g_hostname[16]; |
25 |
extern int g_width; |
extern int g_width; |
26 |
extern int g_height; |
extern int g_height; |
27 |
extern int g_keylayout; |
extern unsigned int g_keylayout; |
28 |
extern int g_keyboard_type; |
extern int g_keyboard_type; |
29 |
extern int g_keyboard_subtype; |
extern int g_keyboard_subtype; |
30 |
extern int g_keyboard_functionkeys; |
extern int g_keyboard_functionkeys; |
31 |
extern BOOL g_encryption; |
extern RD_BOOL g_encryption; |
32 |
extern BOOL g_licence_issued; |
extern RD_BOOL g_licence_issued; |
33 |
extern BOOL g_use_rdp5; |
extern RD_BOOL g_use_rdp5; |
34 |
extern BOOL g_console_session; |
extern RD_BOOL g_console_session; |
35 |
extern int g_server_bpp; |
extern int g_server_depth; |
36 |
extern uint16 mcs_userid; |
extern uint16 mcs_userid; |
37 |
extern VCHANNEL g_channels[]; |
extern VCHANNEL g_channels[]; |
38 |
extern unsigned int g_num_channels; |
extern unsigned int g_num_channels; |
39 |
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40 |
static int rc4_key_len; |
static int rc4_key_len; |
41 |
static RC4_KEY rc4_decrypt_key; |
static SSL_RC4 rc4_decrypt_key; |
42 |
static RC4_KEY rc4_encrypt_key; |
static SSL_RC4 rc4_encrypt_key; |
43 |
static RSA *server_public_key; |
static uint32 server_public_key_len; |
44 |
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45 |
static uint8 sec_sign_key[16]; |
static uint8 sec_sign_key[16]; |
46 |
static uint8 sec_decrypt_key[16]; |
static uint8 sec_decrypt_key[16]; |
47 |
static uint8 sec_encrypt_key[16]; |
static uint8 sec_encrypt_key[16]; |
48 |
static uint8 sec_decrypt_update_key[16]; |
static uint8 sec_decrypt_update_key[16]; |
49 |
static uint8 sec_encrypt_update_key[16]; |
static uint8 sec_encrypt_update_key[16]; |
50 |
static uint8 sec_crypted_random[SEC_MODULUS_SIZE]; |
static uint8 sec_crypted_random[SEC_MAX_MODULUS_SIZE]; |
51 |
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uint16 g_server_rdp_version = 0; |
uint16 g_server_rdp_version = 0; |
53 |
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54 |
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/* These values must be available to reset state - Session Directory */ |
55 |
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static int sec_encrypt_use_count = 0; |
56 |
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static int sec_decrypt_use_count = 0; |
57 |
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58 |
/* |
/* |
59 |
* I believe this is based on SSLv3 with the following differences: |
* I believe this is based on SSLv3 with the following differences: |
60 |
* MAC algorithm (5.2.3.1) uses only 32-bit length in place of seq_num/type/length fields |
* MAC algorithm (5.2.3.1) uses only 32-bit length in place of seq_num/type/length fields |
74 |
{ |
{ |
75 |
uint8 shasig[20]; |
uint8 shasig[20]; |
76 |
uint8 pad[4]; |
uint8 pad[4]; |
77 |
SHA_CTX sha; |
SSL_SHA1 sha1; |
78 |
MD5_CTX md5; |
SSL_MD5 md5; |
79 |
int i; |
int i; |
80 |
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81 |
for (i = 0; i < 3; i++) |
for (i = 0; i < 3; i++) |
82 |
{ |
{ |
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memset(pad, salt + i, i + 1); |
memset(pad, salt + i, i + 1); |
84 |
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85 |
SHA1_Init(&sha); |
ssl_sha1_init(&sha1); |
86 |
SHA1_Update(&sha, pad, i + 1); |
ssl_sha1_update(&sha1, pad, i + 1); |
87 |
SHA1_Update(&sha, in, 48); |
ssl_sha1_update(&sha1, in, 48); |
88 |
SHA1_Update(&sha, salt1, 32); |
ssl_sha1_update(&sha1, salt1, 32); |
89 |
SHA1_Update(&sha, salt2, 32); |
ssl_sha1_update(&sha1, salt2, 32); |
90 |
SHA1_Final(shasig, &sha); |
ssl_sha1_final(&sha1, shasig); |
91 |
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MD5_Init(&md5); |
ssl_md5_init(&md5); |
93 |
MD5_Update(&md5, in, 48); |
ssl_md5_update(&md5, in, 48); |
94 |
MD5_Update(&md5, shasig, 20); |
ssl_md5_update(&md5, shasig, 20); |
95 |
MD5_Final(&out[i * 16], &md5); |
ssl_md5_final(&md5, &out[i * 16]); |
96 |
} |
} |
97 |
} |
} |
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void |
void |
103 |
sec_hash_16(uint8 * out, uint8 * in, uint8 * salt1, uint8 * salt2) |
sec_hash_16(uint8 * out, uint8 * in, uint8 * salt1, uint8 * salt2) |
104 |
{ |
{ |
105 |
MD5_CTX md5; |
SSL_MD5 md5; |
106 |
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107 |
MD5_Init(&md5); |
ssl_md5_init(&md5); |
108 |
MD5_Update(&md5, in, 16); |
ssl_md5_update(&md5, in, 16); |
109 |
MD5_Update(&md5, salt1, 32); |
ssl_md5_update(&md5, salt1, 32); |
110 |
MD5_Update(&md5, salt2, 32); |
ssl_md5_update(&md5, salt2, 32); |
111 |
MD5_Final(out, &md5); |
ssl_md5_final(&md5, out); |
112 |
} |
} |
113 |
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/* Reduce key entropy from 64 to 40 bits */ |
/* Reduce key entropy from 64 to 40 bits */ |
197 |
uint8 shasig[20]; |
uint8 shasig[20]; |
198 |
uint8 md5sig[16]; |
uint8 md5sig[16]; |
199 |
uint8 lenhdr[4]; |
uint8 lenhdr[4]; |
200 |
SHA_CTX sha; |
SSL_SHA1 sha1; |
201 |
MD5_CTX md5; |
SSL_MD5 md5; |
202 |
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203 |
buf_out_uint32(lenhdr, datalen); |
buf_out_uint32(lenhdr, datalen); |
204 |
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205 |
SHA1_Init(&sha); |
ssl_sha1_init(&sha1); |
206 |
SHA1_Update(&sha, session_key, keylen); |
ssl_sha1_update(&sha1, session_key, keylen); |
207 |
SHA1_Update(&sha, pad_54, 40); |
ssl_sha1_update(&sha1, pad_54, 40); |
208 |
SHA1_Update(&sha, lenhdr, 4); |
ssl_sha1_update(&sha1, lenhdr, 4); |
209 |
SHA1_Update(&sha, data, datalen); |
ssl_sha1_update(&sha1, data, datalen); |
210 |
SHA1_Final(shasig, &sha); |
ssl_sha1_final(&sha1, shasig); |
211 |
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MD5_Init(&md5); |
ssl_md5_init(&md5); |
213 |
MD5_Update(&md5, session_key, keylen); |
ssl_md5_update(&md5, session_key, keylen); |
214 |
MD5_Update(&md5, pad_92, 48); |
ssl_md5_update(&md5, pad_92, 48); |
215 |
MD5_Update(&md5, shasig, 20); |
ssl_md5_update(&md5, shasig, 20); |
216 |
MD5_Final(md5sig, &md5); |
ssl_md5_final(&md5, md5sig); |
217 |
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218 |
memcpy(signature, md5sig, siglen); |
memcpy(signature, md5sig, siglen); |
219 |
} |
} |
223 |
sec_update(uint8 * key, uint8 * update_key) |
sec_update(uint8 * key, uint8 * update_key) |
224 |
{ |
{ |
225 |
uint8 shasig[20]; |
uint8 shasig[20]; |
226 |
SHA_CTX sha; |
SSL_SHA1 sha1; |
227 |
MD5_CTX md5; |
SSL_MD5 md5; |
228 |
RC4_KEY update; |
SSL_RC4 update; |
229 |
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230 |
SHA1_Init(&sha); |
ssl_sha1_init(&sha1); |
231 |
SHA1_Update(&sha, update_key, rc4_key_len); |
ssl_sha1_update(&sha1, update_key, rc4_key_len); |
232 |
SHA1_Update(&sha, pad_54, 40); |
ssl_sha1_update(&sha1, pad_54, 40); |
233 |
SHA1_Update(&sha, key, rc4_key_len); |
ssl_sha1_update(&sha1, key, rc4_key_len); |
234 |
SHA1_Final(shasig, &sha); |
ssl_sha1_final(&sha1, shasig); |
235 |
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236 |
MD5_Init(&md5); |
ssl_md5_init(&md5); |
237 |
MD5_Update(&md5, update_key, rc4_key_len); |
ssl_md5_update(&md5, update_key, rc4_key_len); |
238 |
MD5_Update(&md5, pad_92, 48); |
ssl_md5_update(&md5, pad_92, 48); |
239 |
MD5_Update(&md5, shasig, 20); |
ssl_md5_update(&md5, shasig, 20); |
240 |
MD5_Final(key, &md5); |
ssl_md5_final(&md5, key); |
241 |
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RC4_set_key(&update, rc4_key_len, key); |
ssl_rc4_set_key(&update, key, rc4_key_len); |
243 |
RC4(&update, rc4_key_len, key, key); |
ssl_rc4_crypt(&update, key, key, rc4_key_len); |
244 |
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245 |
if (rc4_key_len == 8) |
if (rc4_key_len == 8) |
246 |
sec_make_40bit(key); |
sec_make_40bit(key); |
250 |
static void |
static void |
251 |
sec_encrypt(uint8 * data, int length) |
sec_encrypt(uint8 * data, int length) |
252 |
{ |
{ |
253 |
static int use_count; |
if (sec_encrypt_use_count == 4096) |
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if (use_count == 4096) |
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{ |
{ |
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sec_update(sec_encrypt_key, sec_encrypt_update_key); |
sec_update(sec_encrypt_key, sec_encrypt_update_key); |
256 |
RC4_set_key(&rc4_encrypt_key, rc4_key_len, sec_encrypt_key); |
ssl_rc4_set_key(&rc4_encrypt_key, sec_encrypt_key, rc4_key_len); |
257 |
use_count = 0; |
sec_encrypt_use_count = 0; |
258 |
} |
} |
259 |
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RC4(&rc4_encrypt_key, length, data, data); |
ssl_rc4_crypt(&rc4_encrypt_key, data, data, length); |
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use_count++; |
sec_encrypt_use_count++; |
262 |
} |
} |
263 |
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264 |
/* Decrypt data using RC4 */ |
/* Decrypt data using RC4 */ |
265 |
void |
void |
266 |
sec_decrypt(uint8 * data, int length) |
sec_decrypt(uint8 * data, int length) |
267 |
{ |
{ |
268 |
static int use_count; |
if (sec_decrypt_use_count == 4096) |
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if (use_count == 4096) |
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{ |
{ |
270 |
sec_update(sec_decrypt_key, sec_decrypt_update_key); |
sec_update(sec_decrypt_key, sec_decrypt_update_key); |
271 |
RC4_set_key(&rc4_decrypt_key, rc4_key_len, sec_decrypt_key); |
ssl_rc4_set_key(&rc4_decrypt_key, sec_decrypt_key, rc4_key_len); |
272 |
use_count = 0; |
sec_decrypt_use_count = 0; |
273 |
} |
} |
274 |
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275 |
RC4(&rc4_decrypt_key, length, data, data); |
ssl_rc4_crypt(&rc4_decrypt_key, data, data, length); |
276 |
use_count++; |
sec_decrypt_use_count++; |
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} |
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static void |
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reverse(uint8 * p, int len) |
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{ |
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int i, j; |
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uint8 temp; |
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for (i = 0, j = len - 1; i < j; i++, j--) |
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{ |
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temp = p[i]; |
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p[i] = p[j]; |
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p[j] = temp; |
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} |
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277 |
} |
} |
278 |
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/* Perform an RSA public key encryption operation */ |
/* Perform an RSA public key encryption operation */ |
280 |
static void |
static void |
281 |
sec_rsa_encrypt(uint8 * out, uint8 * in, int len, uint8 * modulus, uint8 * exponent) |
sec_rsa_encrypt(uint8 * out, uint8 * in, int len, uint32 modulus_size, uint8 * modulus, |
282 |
|
uint8 * exponent) |
283 |
{ |
{ |
284 |
BN_CTX *ctx; |
ssl_rsa_encrypt(out, in, len, modulus_size, modulus, exponent); |
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BIGNUM mod, exp, x, y; |
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uint8 inr[SEC_MODULUS_SIZE]; |
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int outlen; |
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reverse(modulus, SEC_MODULUS_SIZE); |
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reverse(exponent, SEC_EXPONENT_SIZE); |
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memcpy(inr, in, len); |
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reverse(inr, len); |
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ctx = BN_CTX_new(); |
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BN_init(&mod); |
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BN_init(&exp); |
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BN_init(&x); |
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BN_init(&y); |
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BN_bin2bn(modulus, SEC_MODULUS_SIZE, &mod); |
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BN_bin2bn(exponent, SEC_EXPONENT_SIZE, &exp); |
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BN_bin2bn(inr, len, &x); |
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BN_mod_exp(&y, &x, &exp, &mod, ctx); |
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outlen = BN_bn2bin(&y, out); |
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reverse(out, outlen); |
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if (outlen < SEC_MODULUS_SIZE) |
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memset(out + outlen, 0, SEC_MODULUS_SIZE - outlen); |
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BN_free(&y); |
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BN_clear_free(&x); |
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BN_free(&exp); |
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BN_free(&mod); |
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BN_CTX_free(ctx); |
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285 |
} |
} |
286 |
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287 |
/* Initialise secure transport packet */ |
/* Initialise secure transport packet */ |
307 |
{ |
{ |
308 |
int datalen; |
int datalen; |
309 |
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310 |
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#ifdef WITH_SCARD |
311 |
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scard_lock(SCARD_LOCK_SEC); |
312 |
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#endif |
313 |
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314 |
s_pop_layer(s, sec_hdr); |
s_pop_layer(s, sec_hdr); |
315 |
if (!g_licence_issued || (flags & SEC_ENCRYPT)) |
if (!g_licence_issued || (flags & SEC_ENCRYPT)) |
316 |
out_uint32_le(s, flags); |
out_uint32_le(s, flags); |
330 |
} |
} |
331 |
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332 |
mcs_send_to_channel(s, channel); |
mcs_send_to_channel(s, channel); |
333 |
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334 |
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#ifdef WITH_SCARD |
335 |
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scard_unlock(SCARD_LOCK_SEC); |
336 |
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#endif |
337 |
} |
} |
338 |
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339 |
/* Transmit secure transport packet */ |
/* Transmit secure transport packet */ |
349 |
static void |
static void |
350 |
sec_establish_key(void) |
sec_establish_key(void) |
351 |
{ |
{ |
352 |
uint32 length = SEC_MODULUS_SIZE + SEC_PADDING_SIZE; |
uint32 length = server_public_key_len + SEC_PADDING_SIZE; |
353 |
uint32 flags = SEC_CLIENT_RANDOM; |
uint32 flags = SEC_CLIENT_RANDOM; |
354 |
STREAM s; |
STREAM s; |
355 |
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356 |
s = sec_init(flags, 76); |
s = sec_init(flags, length + 4); |
357 |
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|
358 |
out_uint32_le(s, length); |
out_uint32_le(s, length); |
359 |
out_uint8p(s, sec_crypted_random, SEC_MODULUS_SIZE); |
out_uint8p(s, sec_crypted_random, server_public_key_len); |
360 |
out_uint8s(s, SEC_PADDING_SIZE); |
out_uint8s(s, SEC_PADDING_SIZE); |
361 |
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362 |
s_mark_end(s); |
s_mark_end(s); |
420 |
out_uint16_le(s, 1); |
out_uint16_le(s, 1); |
421 |
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422 |
out_uint32(s, 0); |
out_uint32(s, 0); |
423 |
out_uint8(s, g_server_bpp); |
out_uint8(s, g_server_depth); |
424 |
out_uint16_le(s, 0x0700); |
out_uint16_le(s, 0x0700); |
425 |
out_uint8(s, 0); |
out_uint8(s, 0); |
426 |
out_uint32_le(s, 1); |
out_uint32_le(s, 1); |
455 |
} |
} |
456 |
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|
457 |
/* Parse a public key structure */ |
/* Parse a public key structure */ |
458 |
static BOOL |
static RD_BOOL |
459 |
sec_parse_public_key(STREAM s, uint8 ** modulus, uint8 ** exponent) |
sec_parse_public_key(STREAM s, uint8 * modulus, uint8 * exponent) |
460 |
{ |
{ |
461 |
uint32 magic, modulus_len; |
uint32 magic, modulus_len; |
462 |
|
|
468 |
} |
} |
469 |
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|
470 |
in_uint32_le(s, modulus_len); |
in_uint32_le(s, modulus_len); |
471 |
if (modulus_len != SEC_MODULUS_SIZE + SEC_PADDING_SIZE) |
modulus_len -= SEC_PADDING_SIZE; |
472 |
|
if ((modulus_len < SEC_MODULUS_SIZE) || (modulus_len > SEC_MAX_MODULUS_SIZE)) |
473 |
{ |
{ |
474 |
error("modulus len 0x%x\n", modulus_len); |
error("Bad server public key size (%u bits)\n", modulus_len * 8); |
475 |
return False; |
return False; |
476 |
} |
} |
477 |
|
|
478 |
in_uint8s(s, 8); /* modulus_bits, unknown */ |
in_uint8s(s, 8); /* modulus_bits, unknown */ |
479 |
in_uint8p(s, *exponent, SEC_EXPONENT_SIZE); |
in_uint8a(s, exponent, SEC_EXPONENT_SIZE); |
480 |
in_uint8p(s, *modulus, SEC_MODULUS_SIZE); |
in_uint8a(s, modulus, modulus_len); |
481 |
in_uint8s(s, SEC_PADDING_SIZE); |
in_uint8s(s, SEC_PADDING_SIZE); |
482 |
|
server_public_key_len = modulus_len; |
483 |
|
|
484 |
return s_check(s); |
return s_check(s); |
485 |
} |
} |
486 |
|
|
487 |
static BOOL |
/* Parse a public signature structure */ |
488 |
sec_parse_x509_key(X509 * cert) |
static RD_BOOL |
489 |
{ |
sec_parse_public_sig(STREAM s, uint32 len, uint8 * modulus, uint8 * exponent) |
490 |
EVP_PKEY *epk = NULL; |
{ |
491 |
/* By some reason, Microsoft sets the OID of the Public RSA key to |
uint8 signature[SEC_MAX_MODULUS_SIZE]; |
492 |
the oid for "MD5 with RSA Encryption" instead of "RSA Encryption" |
uint32 sig_len; |
493 |
|
|
494 |
Kudos to Richard Levitte for the following (. intiutive .) |
if (len != 72) |
495 |
lines of code that resets the OID and let's us extract the key. */ |
{ |
496 |
if (OBJ_obj2nid(cert->cert_info->key->algor->algorithm) == NID_md5WithRSAEncryption) |
return True; |
497 |
{ |
} |
498 |
DEBUG_RDP5(("Re-setting algorithm type to RSA in server certificate\n")); |
memset(signature, 0, sizeof(signature)); |
499 |
cert->cert_info->key->algor->algorithm = OBJ_nid2obj(NID_rsaEncryption); |
sig_len = len - 8; |
500 |
} |
in_uint8a(s, signature, sig_len); |
501 |
epk = X509_get_pubkey(cert); |
return ssl_sig_ok(exponent, SEC_EXPONENT_SIZE, modulus, server_public_key_len, |
502 |
if (NULL == epk) |
signature, sig_len); |
|
{ |
|
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error("Failed to extract public key from certificate\n"); |
|
|
return False; |
|
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} |
|
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server_public_key = (RSA *) epk->pkey.ptr; |
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return True; |
|
503 |
} |
} |
504 |
|
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|
|
|
505 |
/* Parse a crypto information structure */ |
/* Parse a crypto information structure */ |
506 |
static BOOL |
static RD_BOOL |
507 |
sec_parse_crypt_info(STREAM s, uint32 * rc4_key_size, |
sec_parse_crypt_info(STREAM s, uint32 * rc4_key_size, |
508 |
uint8 ** server_random, uint8 ** modulus, uint8 ** exponent) |
uint8 ** server_random, uint8 * modulus, uint8 * exponent) |
509 |
{ |
{ |
510 |
uint32 crypt_level, random_len, rsa_info_len; |
uint32 crypt_level, random_len, rsa_info_len; |
511 |
uint32 cacert_len, cert_len, flags; |
uint32 cacert_len, cert_len, flags; |
512 |
X509 *cacert, *server_cert; |
SSL_CERT *cacert, *server_cert; |
513 |
|
SSL_RKEY *server_public_key; |
514 |
uint16 tag, length; |
uint16 tag, length; |
515 |
uint8 *next_tag, *end; |
uint8 *next_tag, *end; |
516 |
|
|
557 |
break; |
break; |
558 |
|
|
559 |
case SEC_TAG_KEYSIG: |
case SEC_TAG_KEYSIG: |
560 |
/* Is this a Microsoft key that we just got? */ |
if (!sec_parse_public_sig(s, length, modulus, exponent)) |
561 |
/* Care factor: zero! */ |
return False; |
|
/* Actually, it would probably be a good idea to check if the public key is signed with this key, and then store this |
|
|
key as a known key of the hostname. This would prevent some MITM-attacks. */ |
|
562 |
break; |
break; |
563 |
|
|
564 |
default: |
default: |
574 |
|
|
575 |
DEBUG_RDP5(("We're going for the RDP5-style encryption\n")); |
DEBUG_RDP5(("We're going for the RDP5-style encryption\n")); |
576 |
in_uint32_le(s, certcount); /* Number of certificates */ |
in_uint32_le(s, certcount); /* Number of certificates */ |
|
|
|
577 |
if (certcount < 2) |
if (certcount < 2) |
578 |
{ |
{ |
579 |
error("Server didn't send enough X509 certificates\n"); |
error("Server didn't send enough X509 certificates\n"); |
580 |
return False; |
return False; |
581 |
} |
} |
|
|
|
582 |
for (; certcount > 2; certcount--) |
for (; certcount > 2; certcount--) |
583 |
{ /* ignore all the certificates between the root and the signing CA */ |
{ /* ignore all the certificates between the root and the signing CA */ |
584 |
uint32 ignorelen; |
uint32 ignorelen; |
585 |
X509 *ignorecert; |
SSL_CERT *ignorecert; |
586 |
|
|
587 |
DEBUG_RDP5(("Ignored certs left: %d\n", certcount)); |
DEBUG_RDP5(("Ignored certs left: %d\n", certcount)); |
|
|
|
588 |
in_uint32_le(s, ignorelen); |
in_uint32_le(s, ignorelen); |
589 |
DEBUG_RDP5(("Ignored Certificate length is %d\n", ignorelen)); |
DEBUG_RDP5(("Ignored Certificate length is %d\n", ignorelen)); |
590 |
ignorecert = d2i_X509(NULL, &(s->p), ignorelen); |
ignorecert = ssl_cert_read(s->p, ignorelen); |
591 |
|
in_uint8s(s, ignorelen); |
592 |
if (ignorecert == NULL) |
if (ignorecert == NULL) |
593 |
{ /* XXX: error out? */ |
{ /* XXX: error out? */ |
594 |
DEBUG_RDP5(("got a bad cert: this will probably screw up the rest of the communication\n")); |
DEBUG_RDP5(("got a bad cert: this will probably screw up the rest of the communication\n")); |
596 |
|
|
597 |
#ifdef WITH_DEBUG_RDP5 |
#ifdef WITH_DEBUG_RDP5 |
598 |
DEBUG_RDP5(("cert #%d (ignored):\n", certcount)); |
DEBUG_RDP5(("cert #%d (ignored):\n", certcount)); |
599 |
X509_print_fp(stdout, ignorecert); |
ssl_cert_print_fp(stdout, ignorecert); |
600 |
#endif |
#endif |
601 |
} |
} |
602 |
|
/* Do da funky X.509 stuffy |
|
/* Do da funky X.509 stuffy |
|
603 |
|
|
604 |
"How did I find out about this? I looked up and saw a |
"How did I find out about this? I looked up and saw a |
605 |
bright light and when I came to I had a scar on my forehead |
bright light and when I came to I had a scar on my forehead |
607 |
- Peter Gutman in a early version of |
- Peter Gutman in a early version of |
608 |
http://www.cs.auckland.ac.nz/~pgut001/pubs/x509guide.txt |
http://www.cs.auckland.ac.nz/~pgut001/pubs/x509guide.txt |
609 |
*/ |
*/ |
|
|
|
610 |
in_uint32_le(s, cacert_len); |
in_uint32_le(s, cacert_len); |
611 |
DEBUG_RDP5(("CA Certificate length is %d\n", cacert_len)); |
DEBUG_RDP5(("CA Certificate length is %d\n", cacert_len)); |
612 |
cacert = d2i_X509(NULL, &(s->p), cacert_len); |
cacert = ssl_cert_read(s->p, cacert_len); |
613 |
/* Note: We don't need to move s->p here - d2i_X509 is |
in_uint8s(s, cacert_len); |
|
"kind" enough to do it for us */ |
|
614 |
if (NULL == cacert) |
if (NULL == cacert) |
615 |
{ |
{ |
616 |
error("Couldn't load CA Certificate from server\n"); |
error("Couldn't load CA Certificate from server\n"); |
617 |
return False; |
return False; |
618 |
} |
} |
|
|
|
|
/* Currently, we don't use the CA Certificate. |
|
|
FIXME: |
|
|
*) Verify the server certificate (server_cert) with the |
|
|
CA certificate. |
|
|
*) Store the CA Certificate with the hostname of the |
|
|
server we are connecting to as key, and compare it |
|
|
when we connect the next time, in order to prevent |
|
|
MITM-attacks. |
|
|
*/ |
|
|
|
|
619 |
in_uint32_le(s, cert_len); |
in_uint32_le(s, cert_len); |
620 |
DEBUG_RDP5(("Certificate length is %d\n", cert_len)); |
DEBUG_RDP5(("Certificate length is %d\n", cert_len)); |
621 |
server_cert = d2i_X509(NULL, &(s->p), cert_len); |
server_cert = ssl_cert_read(s->p, cert_len); |
622 |
|
in_uint8s(s, cert_len); |
623 |
if (NULL == server_cert) |
if (NULL == server_cert) |
624 |
{ |
{ |
625 |
|
ssl_cert_free(cacert); |
626 |
error("Couldn't load Certificate from server\n"); |
error("Couldn't load Certificate from server\n"); |
627 |
return False; |
return False; |
628 |
} |
} |
629 |
|
if (!ssl_certs_ok(server_cert, cacert)) |
630 |
|
{ |
631 |
|
ssl_cert_free(server_cert); |
632 |
|
ssl_cert_free(cacert); |
633 |
|
error("Security error CA Certificate invalid\n"); |
634 |
|
return False; |
635 |
|
} |
636 |
|
ssl_cert_free(cacert); |
637 |
in_uint8s(s, 16); /* Padding */ |
in_uint8s(s, 16); /* Padding */ |
638 |
|
server_public_key = ssl_cert_to_rkey(server_cert, &server_public_key_len); |
639 |
/* Note: Verifying the server certificate must be done here, |
if (NULL == server_public_key) |
|
before sec_parse_public_key since we'll have to apply |
|
|
serious violence to the key after this */ |
|
|
|
|
|
if (!sec_parse_x509_key(server_cert)) |
|
640 |
{ |
{ |
641 |
DEBUG_RDP5(("Didn't parse X509 correctly\n")); |
DEBUG_RDP5(("Didn't parse X509 correctly\n")); |
642 |
|
ssl_cert_free(server_cert); |
643 |
|
return False; |
644 |
|
} |
645 |
|
ssl_cert_free(server_cert); |
646 |
|
if ((server_public_key_len < SEC_MODULUS_SIZE) || |
647 |
|
(server_public_key_len > SEC_MAX_MODULUS_SIZE)) |
648 |
|
{ |
649 |
|
error("Bad server public key size (%u bits)\n", server_public_key_len * 8); |
650 |
|
ssl_rkey_free(server_public_key); |
651 |
return False; |
return False; |
652 |
} |
} |
653 |
|
if (ssl_rkey_get_exp_mod(server_public_key, exponent, SEC_EXPONENT_SIZE, |
654 |
|
modulus, SEC_MAX_MODULUS_SIZE) != 0) |
655 |
|
{ |
656 |
|
error("Problem extracting RSA exponent, modulus"); |
657 |
|
ssl_rkey_free(server_public_key); |
658 |
|
return False; |
659 |
|
} |
660 |
|
ssl_rkey_free(server_public_key); |
661 |
return True; /* There's some garbage here we don't care about */ |
return True; /* There's some garbage here we don't care about */ |
662 |
} |
} |
663 |
return s_check_end(s); |
return s_check_end(s); |
667 |
static void |
static void |
668 |
sec_process_crypt_info(STREAM s) |
sec_process_crypt_info(STREAM s) |
669 |
{ |
{ |
670 |
uint8 *server_random, *modulus, *exponent; |
uint8 *server_random = NULL; |
671 |
uint8 client_random[SEC_RANDOM_SIZE]; |
uint8 client_random[SEC_RANDOM_SIZE]; |
672 |
|
uint8 modulus[SEC_MAX_MODULUS_SIZE]; |
673 |
|
uint8 exponent[SEC_EXPONENT_SIZE]; |
674 |
uint32 rc4_key_size; |
uint32 rc4_key_size; |
|
uint8 inr[SEC_MODULUS_SIZE]; |
|
675 |
|
|
676 |
if (!sec_parse_crypt_info(s, &rc4_key_size, &server_random, &modulus, &exponent)) |
memset(modulus, 0, sizeof(modulus)); |
677 |
|
memset(exponent, 0, sizeof(exponent)); |
678 |
|
if (!sec_parse_crypt_info(s, &rc4_key_size, &server_random, modulus, exponent)) |
679 |
{ |
{ |
680 |
DEBUG(("Failed to parse crypt info\n")); |
DEBUG(("Failed to parse crypt info\n")); |
681 |
return; |
return; |
682 |
} |
} |
|
|
|
683 |
DEBUG(("Generating client random\n")); |
DEBUG(("Generating client random\n")); |
|
/* Generate a client random, and hence determine encryption keys */ |
|
|
/* This is what the MS client do: */ |
|
|
memset(inr, 0, SEC_RANDOM_SIZE); |
|
|
/* *ARIGL!* Plaintext attack, anyone? |
|
|
I tried doing: |
|
|
generate_random(inr); |
|
|
..but that generates connection errors now and then (yes, |
|
|
"now and then". Something like 0 to 3 attempts needed before a |
|
|
successful connection. Nice. Not! |
|
|
*/ |
|
|
|
|
684 |
generate_random(client_random); |
generate_random(client_random); |
685 |
if (NULL != server_public_key) |
sec_rsa_encrypt(sec_crypted_random, client_random, SEC_RANDOM_SIZE, |
686 |
{ /* Which means we should use |
server_public_key_len, modulus, exponent); |
|
RDP5-style encryption */ |
|
|
|
|
|
memcpy(inr + SEC_RANDOM_SIZE, client_random, SEC_RANDOM_SIZE); |
|
|
reverse(inr + SEC_RANDOM_SIZE, SEC_RANDOM_SIZE); |
|
|
|
|
|
RSA_public_encrypt(SEC_MODULUS_SIZE, |
|
|
inr, sec_crypted_random, server_public_key, RSA_NO_PADDING); |
|
|
|
|
|
reverse(sec_crypted_random, SEC_MODULUS_SIZE); |
|
|
|
|
|
} |
|
|
else |
|
|
{ /* RDP4-style encryption */ |
|
|
sec_rsa_encrypt(sec_crypted_random, |
|
|
client_random, SEC_RANDOM_SIZE, modulus, exponent); |
|
|
} |
|
687 |
sec_generate_keys(client_random, server_random, rc4_key_size); |
sec_generate_keys(client_random, server_random, rc4_key_size); |
688 |
} |
} |
689 |
|
|
697 |
if (1 == g_server_rdp_version) |
if (1 == g_server_rdp_version) |
698 |
{ |
{ |
699 |
g_use_rdp5 = 0; |
g_use_rdp5 = 0; |
700 |
g_server_bpp = 8; |
g_server_depth = 8; |
701 |
} |
} |
702 |
} |
} |
703 |
|
|
786 |
licence_process(s); |
licence_process(s); |
787 |
continue; |
continue; |
788 |
} |
} |
789 |
|
|
790 |
|
if (sec_flags & 0x0400) /* SEC_REDIRECT_ENCRYPT */ |
791 |
|
{ |
792 |
|
uint8 swapbyte; |
793 |
|
|
794 |
|
in_uint8s(s, 8); /* signature */ |
795 |
|
sec_decrypt(s->p, s->end - s->p); |
796 |
|
|
797 |
|
/* Check for a redirect packet, starts with 00 04 */ |
798 |
|
if (s->p[0] == 0 && s->p[1] == 4) |
799 |
|
{ |
800 |
|
/* for some reason the PDU and the length seem to be swapped. |
801 |
|
This isn't good, but we're going to do a byte for byte |
802 |
|
swap. So the first foure value appear as: 00 04 XX YY, |
803 |
|
where XX YY is the little endian length. We're going to |
804 |
|
use 04 00 as the PDU type, so after our swap this will look |
805 |
|
like: XX YY 04 00 */ |
806 |
|
swapbyte = s->p[0]; |
807 |
|
s->p[0] = s->p[2]; |
808 |
|
s->p[2] = swapbyte; |
809 |
|
|
810 |
|
swapbyte = s->p[1]; |
811 |
|
s->p[1] = s->p[3]; |
812 |
|
s->p[3] = swapbyte; |
813 |
|
|
814 |
|
swapbyte = s->p[2]; |
815 |
|
s->p[2] = s->p[3]; |
816 |
|
s->p[3] = swapbyte; |
817 |
|
} |
818 |
|
#ifdef WITH_DEBUG |
819 |
|
/* warning! this debug statement will show passwords in the clear! */ |
820 |
|
hexdump(s->p, s->end - s->p); |
821 |
|
#endif |
822 |
|
} |
823 |
|
|
824 |
} |
} |
825 |
|
|
826 |
if (channel != MCS_GLOBAL_CHANNEL) |
if (channel != MCS_GLOBAL_CHANNEL) |
837 |
} |
} |
838 |
|
|
839 |
/* Establish a secure connection */ |
/* Establish a secure connection */ |
840 |
BOOL |
RD_BOOL |
841 |
sec_connect(char *server, char *username) |
sec_connect(char *server, char *username) |
842 |
{ |
{ |
843 |
struct stream mcs_data; |
struct stream mcs_data; |
857 |
return True; |
return True; |
858 |
} |
} |
859 |
|
|
860 |
|
/* Establish a secure connection */ |
861 |
|
RD_BOOL |
862 |
|
sec_reconnect(char *server) |
863 |
|
{ |
864 |
|
struct stream mcs_data; |
865 |
|
|
866 |
|
/* We exchange some RDP data during the MCS-Connect */ |
867 |
|
mcs_data.size = 512; |
868 |
|
mcs_data.p = mcs_data.data = (uint8 *) xmalloc(mcs_data.size); |
869 |
|
sec_out_mcs_data(&mcs_data); |
870 |
|
|
871 |
|
if (!mcs_reconnect(server, &mcs_data)) |
872 |
|
return False; |
873 |
|
|
874 |
|
/* sec_process_mcs_data(&mcs_data); */ |
875 |
|
if (g_encryption) |
876 |
|
sec_establish_key(); |
877 |
|
xfree(mcs_data.data); |
878 |
|
return True; |
879 |
|
} |
880 |
|
|
881 |
/* Disconnect a connection */ |
/* Disconnect a connection */ |
882 |
void |
void |
883 |
sec_disconnect(void) |
sec_disconnect(void) |
884 |
{ |
{ |
885 |
mcs_disconnect(); |
mcs_disconnect(); |
886 |
} |
} |
887 |
|
|
888 |
|
/* reset the state of the sec layer */ |
889 |
|
void |
890 |
|
sec_reset_state(void) |
891 |
|
{ |
892 |
|
g_server_rdp_version = 0; |
893 |
|
sec_encrypt_use_count = 0; |
894 |
|
sec_decrypt_use_count = 0; |
895 |
|
mcs_reset_state(); |
896 |
|
} |