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libfreerdp/core/security.c
1
21#include <freerdp/config.h>
22
23#include "settings.h"
24#include "security.h"
25
26#include <freerdp/log.h>
27#include <winpr/crypto.h>
28
29#define TAG FREERDP_TAG("core")
30
31static const BYTE A[] = { 'A' };
32static const BYTE BB[] = { 'B', 'B' };
33static const BYTE CCC[] = { 'C', 'C', 'C' };
34
35/* 0x36 repeated 40 times */
36static const BYTE pad1[40] = { "\x36\x36\x36\x36\x36\x36\x36\x36"
37 "\x36\x36\x36\x36\x36\x36\x36\x36"
38 "\x36\x36\x36\x36\x36\x36\x36\x36"
39 "\x36\x36\x36\x36\x36\x36\x36\x36"
40 "\x36\x36\x36\x36\x36\x36\x36\x36" };
41
42/* 0x5C repeated 48 times */
43static const BYTE pad2[48] = { "\x5C\x5C\x5C\x5C\x5C\x5C\x5C\x5C"
44 "\x5C\x5C\x5C\x5C\x5C\x5C\x5C\x5C"
45 "\x5C\x5C\x5C\x5C\x5C\x5C\x5C\x5C"
46 "\x5C\x5C\x5C\x5C\x5C\x5C\x5C\x5C"
47 "\x5C\x5C\x5C\x5C\x5C\x5C\x5C\x5C"
48 "\x5C\x5C\x5C\x5C\x5C\x5C\x5C\x5C" };
49
50static const BYTE fips_reverse_table[256] = {
51 0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0, 0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0,
52 0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8, 0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8,
53 0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4, 0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4,
54 0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec, 0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc,
55 0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2, 0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2,
56 0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea, 0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa,
57 0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6, 0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6,
58 0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee, 0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe,
59 0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1, 0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1,
60 0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9, 0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9,
61 0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5, 0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5,
62 0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed, 0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd,
63 0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3, 0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3,
64 0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb, 0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb,
65 0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7, 0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7,
66 0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef, 0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff
67};
68
69static const BYTE fips_oddparity_table[256] = {
70 0x01, 0x01, 0x02, 0x02, 0x04, 0x04, 0x07, 0x07, 0x08, 0x08, 0x0b, 0x0b, 0x0d, 0x0d, 0x0e, 0x0e,
71 0x10, 0x10, 0x13, 0x13, 0x15, 0x15, 0x16, 0x16, 0x19, 0x19, 0x1a, 0x1a, 0x1c, 0x1c, 0x1f, 0x1f,
72 0x20, 0x20, 0x23, 0x23, 0x25, 0x25, 0x26, 0x26, 0x29, 0x29, 0x2a, 0x2a, 0x2c, 0x2c, 0x2f, 0x2f,
73 0x31, 0x31, 0x32, 0x32, 0x34, 0x34, 0x37, 0x37, 0x38, 0x38, 0x3b, 0x3b, 0x3d, 0x3d, 0x3e, 0x3e,
74 0x40, 0x40, 0x43, 0x43, 0x45, 0x45, 0x46, 0x46, 0x49, 0x49, 0x4a, 0x4a, 0x4c, 0x4c, 0x4f, 0x4f,
75 0x51, 0x51, 0x52, 0x52, 0x54, 0x54, 0x57, 0x57, 0x58, 0x58, 0x5b, 0x5b, 0x5d, 0x5d, 0x5e, 0x5e,
76 0x61, 0x61, 0x62, 0x62, 0x64, 0x64, 0x67, 0x67, 0x68, 0x68, 0x6b, 0x6b, 0x6d, 0x6d, 0x6e, 0x6e,
77 0x70, 0x70, 0x73, 0x73, 0x75, 0x75, 0x76, 0x76, 0x79, 0x79, 0x7a, 0x7a, 0x7c, 0x7c, 0x7f, 0x7f,
78 0x80, 0x80, 0x83, 0x83, 0x85, 0x85, 0x86, 0x86, 0x89, 0x89, 0x8a, 0x8a, 0x8c, 0x8c, 0x8f, 0x8f,
79 0x91, 0x91, 0x92, 0x92, 0x94, 0x94, 0x97, 0x97, 0x98, 0x98, 0x9b, 0x9b, 0x9d, 0x9d, 0x9e, 0x9e,
80 0xa1, 0xa1, 0xa2, 0xa2, 0xa4, 0xa4, 0xa7, 0xa7, 0xa8, 0xa8, 0xab, 0xab, 0xad, 0xad, 0xae, 0xae,
81 0xb0, 0xb0, 0xb3, 0xb3, 0xb5, 0xb5, 0xb6, 0xb6, 0xb9, 0xb9, 0xba, 0xba, 0xbc, 0xbc, 0xbf, 0xbf,
82 0xc1, 0xc1, 0xc2, 0xc2, 0xc4, 0xc4, 0xc7, 0xc7, 0xc8, 0xc8, 0xcb, 0xcb, 0xcd, 0xcd, 0xce, 0xce,
83 0xd0, 0xd0, 0xd3, 0xd3, 0xd5, 0xd5, 0xd6, 0xd6, 0xd9, 0xd9, 0xda, 0xda, 0xdc, 0xdc, 0xdf, 0xdf,
84 0xe0, 0xe0, 0xe3, 0xe3, 0xe5, 0xe5, 0xe6, 0xe6, 0xe9, 0xe9, 0xea, 0xea, 0xec, 0xec, 0xef, 0xef,
85 0xf1, 0xf1, 0xf2, 0xf2, 0xf4, 0xf4, 0xf7, 0xf7, 0xf8, 0xf8, 0xfb, 0xfb, 0xfd, 0xfd, 0xfe, 0xfe
86};
87
88static BOOL security_salted_hash(const BYTE* salt, size_t salt_len, const BYTE* input,
89 size_t length, const BYTE* salt1, size_t salt1_len,
90 const BYTE* salt2, size_t salt2_len, BYTE* output, size_t out_len)
91{
92 WINPR_DIGEST_CTX* sha1 = NULL;
93 WINPR_DIGEST_CTX* md5 = NULL;
94 BYTE sha1_digest[WINPR_SHA1_DIGEST_LENGTH] = { 0 };
95 BOOL result = FALSE;
96
97 /* SaltedHash(Salt, Input, Salt1, Salt2) = MD5(S + SHA1(Input + Salt + Salt1 + Salt2)) */
98 WINPR_ASSERT(out_len >= WINPR_MD5_DIGEST_LENGTH);
99
100 /* SHA1_Digest = SHA1(Input + Salt + Salt1 + Salt2) */
101 if (!(sha1 = winpr_Digest_New()))
102 goto out;
103
104 if (!winpr_Digest_Init(sha1, WINPR_MD_SHA1))
105 goto out;
106
107 if (!winpr_Digest_Update(sha1, input, length)) /* Input */
108 goto out;
109
110 WINPR_ASSERT(salt_len == 48);
111 if (!winpr_Digest_Update(sha1, salt, salt_len)) /* Salt (48 bytes) */
112 goto out;
113
114 WINPR_ASSERT(salt1_len == 32);
115 if (!winpr_Digest_Update(sha1, salt1, salt1_len)) /* Salt1 (32 bytes) */
116 goto out;
117
118 WINPR_ASSERT(salt2_len == 32);
119 if (!winpr_Digest_Update(sha1, salt2, salt2_len)) /* Salt2 (32 bytes) */
120 goto out;
121
122 if (!winpr_Digest_Final(sha1, sha1_digest, sizeof(sha1_digest)))
123 goto out;
124
125 /* SaltedHash(Salt, Input, Salt1, Salt2) = MD5(S + SHA1_Digest) */
126 if (!(md5 = winpr_Digest_New()))
127 goto out;
128
129 /* Allow FIPS override for use of MD5 here, this is used for creating hashes of the
130 * premaster_secret and master_secret */
131 /* used for RDP licensing as described in MS-RDPELE. This is for RDP licensing packets */
132 /* which will already be encrypted under FIPS, so the use of MD5 here is not for sensitive data
133 * protection. */
134 if (!winpr_Digest_Init_Allow_FIPS(md5, WINPR_MD_MD5))
135 goto out;
136
137 if (!winpr_Digest_Update(md5, salt, 48)) /* Salt (48 bytes) */
138 goto out;
139
140 if (!winpr_Digest_Update(md5, sha1_digest, sizeof(sha1_digest))) /* SHA1_Digest */
141 goto out;
142
143 if (!winpr_Digest_Final(md5, output, out_len))
144 goto out;
145
146 result = TRUE;
147out:
148 winpr_Digest_Free(sha1);
149 winpr_Digest_Free(md5);
150 return result;
151}
152
153static BOOL security_premaster_hash(const BYTE* input, size_t length, const BYTE* premaster_secret,
154 size_t pre_len, const BYTE* client_random, size_t client_len,
155 const BYTE* server_random, size_t server_len, BYTE* output,
156 size_t out_len)
157{
158 /* PremasterHash(Input) = SaltedHash(PremasterSecret, Input, ClientRandom, ServerRandom) */
159 return security_salted_hash(premaster_secret, pre_len, input, length, client_random, client_len,
160 server_random, server_len, output, out_len);
161}
162
163BOOL security_master_secret(const BYTE* premaster_secret, size_t pre_len, const BYTE* client_random,
164 size_t client_len, const BYTE* server_random, size_t server_len,
165 BYTE* output, size_t out_len)
166{
167 /* MasterSecret = PremasterHash('A') + PremasterHash('BB') + PremasterHash('CCC') */
168 WINPR_ASSERT(out_len >= 32);
169 return security_premaster_hash(A, sizeof(A), premaster_secret, pre_len, client_random,
170 client_len, server_random, server_len, &output[0], out_len) &&
171 security_premaster_hash(BB, sizeof(BB), premaster_secret, pre_len, client_random,
172 client_len, server_random, server_len, &output[16],
173 out_len - 16) &&
174 security_premaster_hash(CCC, sizeof(CCC), premaster_secret, pre_len, client_random,
175 client_len, server_random, server_len, &output[32],
176 out_len - 32);
177}
178
179static BOOL security_master_hash(const BYTE* input, size_t length, const BYTE* master_secret,
180 size_t master_len, const BYTE* client_random, size_t client_len,
181 const BYTE* server_random, size_t server_len, BYTE* output,
182 size_t out_len)
183{
184 /* MasterHash(Input) = SaltedHash(MasterSecret, Input, ServerRandom, ClientRandom) */
185 return security_salted_hash(master_secret, master_len, input, length, server_random, server_len,
186 client_random, client_len, output, out_len);
187}
188
189BOOL security_session_key_blob(const BYTE* master_secret, size_t master_len,
190 const BYTE* client_random, size_t client_len,
191 const BYTE* server_random, size_t server_len, BYTE* output,
192 size_t out_len)
193{
194 /* MasterHash = MasterHash('A') + MasterHash('BB') + MasterHash('CCC') */
195 WINPR_ASSERT(out_len >= 32);
196 return security_master_hash(A, sizeof(A), master_secret, master_len, client_random, client_len,
197 server_random, server_len, &output[0], 16) &&
198 security_master_hash(BB, sizeof(BB), master_secret, master_len, client_random,
199 client_len, server_random, server_len, &output[16], 16) &&
200 security_master_hash(CCC, sizeof(CCC), master_secret, master_len, client_random,
201 client_len, server_random, server_len, &output[32], out_len - 32);
202}
203
204void security_mac_salt_key(const BYTE* session_key_blob, WINPR_ATTR_UNUSED size_t session_len,
205 WINPR_ATTR_UNUSED const BYTE* client_random,
206 WINPR_ATTR_UNUSED size_t client_len,
207 WINPR_ATTR_UNUSED const BYTE* server_random,
208 WINPR_ATTR_UNUSED size_t server_len, BYTE* output,
209 WINPR_ATTR_UNUSED size_t out_len)
210{
211 /* MacSaltKey = First128Bits(SessionKeyBlob) */
212 WINPR_ASSERT(out_len >= 16);
213 WINPR_ASSERT(session_len >= 16);
214 memcpy(output, session_key_blob, 16);
215}
216
217static BOOL security_md5_16_32_32(const BYTE* in0, const BYTE* in1, const BYTE* in2, BYTE* output,
218 size_t out_len)
219{
220 WINPR_DIGEST_CTX* md5 = NULL;
221 BOOL result = FALSE;
222
223 WINPR_ASSERT(WINPR_MD5_DIGEST_LENGTH <= out_len);
224
225 if (!(md5 = winpr_Digest_New()))
226 return FALSE;
227
228 if (!winpr_Digest_Init(md5, WINPR_MD_MD5))
229 goto out;
230
231 if (!winpr_Digest_Update(md5, in0, 16))
232 goto out;
233
234 if (!winpr_Digest_Update(md5, in1, 32))
235 goto out;
236
237 if (!winpr_Digest_Update(md5, in2, 32))
238 goto out;
239
240 if (!winpr_Digest_Final(md5, output, out_len))
241 goto out;
242
243 result = TRUE;
244out:
245 winpr_Digest_Free(md5);
246 return result;
247}
248
249static BOOL security_md5_16_32_32_Allow_FIPS(const BYTE* in0, const BYTE* in1, const BYTE* in2,
250 BYTE* output, size_t out_len)
251{
252 WINPR_DIGEST_CTX* md5 = NULL;
253 BOOL result = FALSE;
254
255 WINPR_ASSERT(out_len >= WINPR_MD5_DIGEST_LENGTH);
256
257 if (!(md5 = winpr_Digest_New()))
258 return FALSE;
259 if (!winpr_Digest_Init_Allow_FIPS(md5, WINPR_MD_MD5))
260 goto out;
261 if (!winpr_Digest_Update(md5, in0, 16))
262 goto out;
263 if (!winpr_Digest_Update(md5, in1, 32))
264 goto out;
265 if (!winpr_Digest_Update(md5, in2, 32))
266 goto out;
267 if (!winpr_Digest_Final(md5, output, out_len))
268 goto out;
269
270 result = TRUE;
271out:
272 winpr_Digest_Free(md5);
273 return result;
274}
275
276BOOL security_licensing_encryption_key(const BYTE* session_key_blob, size_t session_len,
277 const BYTE* client_random, size_t client_len,
278 const BYTE* server_random, size_t server_len, BYTE* output,
279 size_t out_len)
280{
281 if (session_len < 16)
282 return FALSE;
283 if (client_len < 32)
284 return FALSE;
285 if (server_len < 32)
286 return FALSE;
287 /* LicensingEncryptionKey = MD5(Second128Bits(SessionKeyBlob) + ClientRandom + ServerRandom))
288 * Allow FIPS use of MD5 here, this is just used for creating the licensing encryption key as
289 * described in MS-RDPELE. This is for RDP licensing packets which will already be encrypted
290 * under FIPS, so the use of MD5 here is not for sensitive data protection. */
291 return security_md5_16_32_32_Allow_FIPS(&session_key_blob[16], client_random, server_random,
292 output, out_len);
293}
294
295static void security_UINT32_le(BYTE* output, WINPR_ATTR_UNUSED size_t out_len, UINT32 value)
296{
297 WINPR_ASSERT(output);
298 WINPR_ASSERT(out_len >= 4);
299 output[0] = (value)&0xFF;
300 output[1] = (value >> 8) & 0xFF;
301 output[2] = (value >> 16) & 0xFF;
302 output[3] = (value >> 24) & 0xFF;
303}
304
305BOOL security_mac_data(const BYTE* mac_salt_key, size_t mac_salt_key_length, const BYTE* data,
306 size_t length, BYTE* output, size_t output_length)
307{
308 WINPR_DIGEST_CTX* sha1 = NULL;
309 WINPR_DIGEST_CTX* md5 = NULL;
310 BYTE length_le[4] = { 0 };
311 BYTE sha1_digest[WINPR_SHA1_DIGEST_LENGTH] = { 0 };
312 BOOL result = FALSE;
313
314 WINPR_ASSERT(length <= UINT32_MAX);
315 WINPR_ASSERT(mac_salt_key_length == WINPR_MD5_DIGEST_LENGTH);
316 WINPR_ASSERT(output_length == WINPR_MD5_DIGEST_LENGTH);
317
318 /* MacData = MD5(MacSaltKey + pad2 + SHA1(MacSaltKey + pad1 + length + data)) */
319 security_UINT32_le(length_le, sizeof(length_le),
320 (UINT32)length); /* length must be little-endian */
321
322 /* SHA1_Digest = SHA1(MacSaltKey + pad1 + length + data) */
323 if (!(sha1 = winpr_Digest_New()))
324 goto out;
325
326 if (!winpr_Digest_Init(sha1, WINPR_MD_SHA1))
327 goto out;
328
329 if (!winpr_Digest_Update(sha1, mac_salt_key, mac_salt_key_length)) /* MacSaltKey */
330 goto out;
331
332 if (!winpr_Digest_Update(sha1, pad1, sizeof(pad1))) /* pad1 */
333 goto out;
334
335 if (!winpr_Digest_Update(sha1, length_le, sizeof(length_le))) /* length */
336 goto out;
337
338 if (!winpr_Digest_Update(sha1, data, length)) /* data */
339 goto out;
340
341 if (!winpr_Digest_Final(sha1, sha1_digest, sizeof(sha1_digest)))
342 goto out;
343
344 /* MacData = MD5(MacSaltKey + pad2 + SHA1_Digest) */
345 if (!(md5 = winpr_Digest_New()))
346 goto out;
347
348 /* Allow FIPS override for use of MD5 here, this is only used for creating the MACData field of
349 * the */
350 /* Client Platform Challenge Response packet (from MS-RDPELE section 2.2.2.5). This is for RDP
351 * licensing packets */
352 /* which will already be encrypted under FIPS, so the use of MD5 here is not for sensitive data
353 * protection. */
354 if (!winpr_Digest_Init_Allow_FIPS(md5, WINPR_MD_MD5))
355 goto out;
356
357 if (!winpr_Digest_Update(md5, mac_salt_key, 16)) /* MacSaltKey */
358 goto out;
359
360 if (!winpr_Digest_Update(md5, pad2, sizeof(pad2))) /* pad2 */
361 goto out;
362
363 if (!winpr_Digest_Update(md5, sha1_digest, sizeof(sha1_digest))) /* SHA1_Digest */
364 goto out;
365
366 if (!winpr_Digest_Final(md5, output, output_length))
367 goto out;
368
369 result = TRUE;
370out:
371 if (!result)
372 WLog_ERR(TAG, "failed to create security mac");
373 winpr_Digest_Free(sha1);
374 winpr_Digest_Free(md5);
375 return result;
376}
377
378BOOL security_mac_signature(rdpRdp* rdp, const BYTE* data, UINT32 length, BYTE* output,
379 size_t out_len)
380{
381 WINPR_DIGEST_CTX* sha1 = NULL;
382 WINPR_DIGEST_CTX* md5 = NULL;
383 BYTE length_le[4] = { 0 };
384 BYTE md5_digest[WINPR_MD5_DIGEST_LENGTH] = { 0 };
385 BYTE sha1_digest[WINPR_SHA1_DIGEST_LENGTH] = { 0 };
386 BOOL result = FALSE;
387
388 WINPR_ASSERT(rdp);
389 WINPR_ASSERT(data || (length == 0));
390 WINPR_ASSERT(output);
391 WINPR_ASSERT(out_len >= 8);
392 if (out_len < 8)
393 return FALSE;
394
395 security_UINT32_le(length_le, sizeof(length_le), length); /* length must be little-endian */
396
397 /* SHA1_Digest = SHA1(MACKeyN + pad1 + length + data) */
398 if (!(sha1 = winpr_Digest_New()))
399 goto out;
400
401 if (!winpr_Digest_Init(sha1, WINPR_MD_SHA1))
402 goto out;
403
404 if (!winpr_Digest_Update(sha1, rdp->sign_key, rdp->rc4_key_len)) /* MacKeyN */
405 goto out;
406
407 if (!winpr_Digest_Update(sha1, pad1, sizeof(pad1))) /* pad1 */
408 goto out;
409
410 if (!winpr_Digest_Update(sha1, length_le, sizeof(length_le))) /* length */
411 goto out;
412
413 if (!winpr_Digest_Update(sha1, data, length)) /* data */
414 goto out;
415
416 if (!winpr_Digest_Final(sha1, sha1_digest, sizeof(sha1_digest)))
417 goto out;
418
419 /* MACSignature = First64Bits(MD5(MACKeyN + pad2 + SHA1_Digest)) */
420 if (!(md5 = winpr_Digest_New()))
421 goto out;
422
423 if (!winpr_Digest_Init(md5, WINPR_MD_MD5))
424 goto out;
425
426 if (!winpr_Digest_Update(md5, rdp->sign_key, rdp->rc4_key_len)) /* MacKeyN */
427 goto out;
428
429 if (!winpr_Digest_Update(md5, pad2, sizeof(pad2))) /* pad2 */
430 goto out;
431
432 if (!winpr_Digest_Update(md5, sha1_digest, sizeof(sha1_digest))) /* SHA1_Digest */
433 goto out;
434
435 if (!winpr_Digest_Final(md5, md5_digest, sizeof(md5_digest)))
436 goto out;
437
438 memcpy(output, md5_digest, 8);
439 result = TRUE;
440out:
441 if (!result)
442 WLog_WARN(TAG, "security mac generation failed");
443 winpr_Digest_Free(sha1);
444 winpr_Digest_Free(md5);
445 return result;
446}
447
448BOOL security_salted_mac_signature(rdpRdp* rdp, const BYTE* data, UINT32 length, BOOL encryption,
449 BYTE* output, size_t out_len)
450{
451 WINPR_DIGEST_CTX* sha1 = NULL;
452 WINPR_DIGEST_CTX* md5 = NULL;
453 BYTE length_le[4] = { 0 };
454 BYTE use_count_le[4] = { 0 };
455 BYTE md5_digest[WINPR_MD5_DIGEST_LENGTH] = { 0 };
456 BYTE sha1_digest[WINPR_SHA1_DIGEST_LENGTH] = { 0 };
457 BOOL result = FALSE;
458
459 WINPR_ASSERT(rdp);
460 WINPR_ASSERT(data || (length == 0));
461 WINPR_ASSERT(output);
462 WINPR_ASSERT(out_len >= 8);
463 if (out_len < 8)
464 return FALSE;
465
466 security_UINT32_le(length_le, sizeof(length_le), length); /* length must be little-endian */
467
468 if (encryption)
469 {
470 security_UINT32_le(use_count_le, sizeof(use_count_le), rdp->encrypt_checksum_use_count);
471 }
472 else
473 {
474 /*
475 * We calculate checksum on plain text, so we must have already
476 * decrypt it, which means decrypt_checksum_use_count is off by one.
477 */
478 security_UINT32_le(use_count_le, sizeof(use_count_le),
479 rdp->decrypt_checksum_use_count - 1u);
480 }
481
482 /* SHA1_Digest = SHA1(MACKeyN + pad1 + length + data) */
483 if (!(sha1 = winpr_Digest_New()))
484 goto out;
485
486 if (!winpr_Digest_Init(sha1, WINPR_MD_SHA1))
487 goto out;
488
489 if (!winpr_Digest_Update(sha1, rdp->sign_key, rdp->rc4_key_len)) /* MacKeyN */
490 goto out;
491
492 if (!winpr_Digest_Update(sha1, pad1, sizeof(pad1))) /* pad1 */
493 goto out;
494
495 if (!winpr_Digest_Update(sha1, length_le, sizeof(length_le))) /* length */
496 goto out;
497
498 if (!winpr_Digest_Update(sha1, data, length)) /* data */
499 goto out;
500
501 if (!winpr_Digest_Update(sha1, use_count_le, sizeof(use_count_le))) /* encryptionCount */
502 goto out;
503
504 if (!winpr_Digest_Final(sha1, sha1_digest, sizeof(sha1_digest)))
505 goto out;
506
507 /* MACSignature = First64Bits(MD5(MACKeyN + pad2 + SHA1_Digest)) */
508 if (!(md5 = winpr_Digest_New()))
509 goto out;
510
511 if (!winpr_Digest_Init(md5, WINPR_MD_MD5))
512 goto out;
513
514 if (!winpr_Digest_Update(md5, rdp->sign_key, rdp->rc4_key_len)) /* MacKeyN */
515 goto out;
516
517 if (!winpr_Digest_Update(md5, pad2, sizeof(pad2))) /* pad2 */
518 goto out;
519
520 if (!winpr_Digest_Update(md5, sha1_digest, sizeof(sha1_digest))) /* SHA1_Digest */
521 goto out;
522
523 if (!winpr_Digest_Final(md5, md5_digest, sizeof(md5_digest)))
524 goto out;
525
526 memcpy(output, md5_digest, 8);
527 result = TRUE;
528out:
529 if (!result)
530 WLog_WARN(TAG, "security mac signature generation failed");
531
532 winpr_Digest_Free(sha1);
533 winpr_Digest_Free(md5);
534 return result;
535}
536
537static BOOL security_A(const BYTE* master_secret, size_t master_len, const BYTE* client_random,
538 size_t client_len, const BYTE* server_random, size_t server_len,
539 BYTE* output, size_t out_len)
540{
541 WINPR_ASSERT(out_len >= 32);
542
543 return security_premaster_hash(A, sizeof(A), master_secret, master_len, client_random,
544 client_len, server_random, server_len, &output[0], 16) &&
545 security_premaster_hash(BB, sizeof(BB), master_secret, master_len, client_random,
546 client_len, server_random, server_len, &output[16], 16) &&
547 security_premaster_hash(CCC, sizeof(CCC), master_secret, master_len, client_random,
548 client_len, server_random, server_len, &output[32],
549 out_len - 32);
550}
551
552static BOOL security_X(const BYTE* master_secret, size_t master_len, const BYTE* client_random,
553 size_t client_len, const BYTE* server_random, size_t server_len,
554 BYTE* output, size_t out_len)
555{
556 const BYTE X[] = { 'X' };
557 const BYTE YY[] = { 'Y', 'Y' };
558 const BYTE ZZZ[] = { 'Z', 'Z', 'Z' };
559
560 WINPR_ASSERT(out_len >= 32);
561
562 return security_premaster_hash(X, sizeof(X), master_secret, master_len, client_random,
563 client_len, server_random, server_len, &output[0], 16) &&
564 security_premaster_hash(YY, sizeof(YY), master_secret, master_len, client_random,
565 client_len, server_random, server_len, &output[16], 16) &&
566 security_premaster_hash(ZZZ, sizeof(ZZZ), master_secret, master_len, client_random,
567 client_len, server_random, server_len, &output[32],
568 out_len - 32);
569}
570
571static void fips_expand_key_bits(const BYTE* in, WINPR_ATTR_UNUSED size_t in_len, BYTE* out,
572 WINPR_ATTR_UNUSED size_t out_len)
573{
574 BYTE buf[21] = { 0 };
575
576 WINPR_ASSERT(in);
577 WINPR_ASSERT(in_len >= sizeof(buf));
578
579 WINPR_ASSERT(out);
580 WINPR_ASSERT(out_len >= 24);
581
582 /* reverse every byte in the key */
583 for (size_t i = 0; i < sizeof(buf); i++)
584 buf[i] = fips_reverse_table[in[i]];
585
586 /* insert a zero-bit after every 7th bit */
587 size_t b = 0;
588 for (size_t i = 0; i < 24; i++, b += 7)
589 {
590 const size_t p = b / 8;
591 const size_t r = b % 8;
592
593 WINPR_ASSERT(p < sizeof(buf));
594 if (r <= 1)
595 {
596 out[i] = (buf[p] << r) & 0xfe;
597 }
598 else
599 {
600 WINPR_ASSERT(p + 1 < sizeof(buf));
601 /* c is accumulator */
602 BYTE c = (BYTE)(buf[p] << r) & 0xFF;
603 c |= buf[p + 1] >> (8 - r);
604 out[i] = c & 0xfe;
605 }
606 }
607
608 /* reverse every byte */
609 /* alter lsb so the byte has odd parity */
610 for (size_t i = 0; i < 24; i++)
611 out[i] = fips_oddparity_table[fips_reverse_table[out[i]]];
612}
613
614BOOL security_establish_keys(rdpRdp* rdp)
615{
616 BYTE pre_master_secret[48] = { 0 };
617 BYTE master_secret[48] = { 0 };
618 BYTE session_key_blob[48] = { 0 };
619 BYTE salt[] = { 0xD1, 0x26, 0x9E }; /* 40 bits: 3 bytes, 56 bits: 1 byte */
620 BOOL status = FALSE;
621
622 WINPR_ASSERT(rdp);
623 const rdpSettings* settings = rdp->settings;
624 WINPR_ASSERT(settings);
625
626 const BYTE* server_random = freerdp_settings_get_pointer(settings, FreeRDP_ServerRandom);
627 const BYTE* client_random = freerdp_settings_get_pointer(settings, FreeRDP_ClientRandom);
628 WINPR_ASSERT(client_random);
629 WINPR_ASSERT(server_random);
630
631 const UINT32 ClientRandomLength =
632 freerdp_settings_get_uint32(settings, FreeRDP_ClientRandomLength);
633 const UINT32 ServerRandomLength =
634 freerdp_settings_get_uint32(settings, FreeRDP_ServerRandomLength);
635 WINPR_ASSERT(ClientRandomLength == 32);
636 WINPR_ASSERT(ServerRandomLength == 32);
637
638 if (settings->EncryptionMethods == ENCRYPTION_METHOD_FIPS)
639 {
640 BYTE client_encrypt_key_t[WINPR_SHA1_DIGEST_LENGTH + 1] = { 0 };
641 BYTE client_decrypt_key_t[WINPR_SHA1_DIGEST_LENGTH + 1] = { 0 };
642 WINPR_DIGEST_CTX* sha1 = winpr_Digest_New();
643 if (!sha1)
644 return FALSE;
645
646 if (!winpr_Digest_Init(sha1, WINPR_MD_SHA1) ||
647 !winpr_Digest_Update(sha1, client_random + 16, 16) ||
648 !winpr_Digest_Update(sha1, server_random + 16, 16) ||
649 !winpr_Digest_Final(sha1, client_encrypt_key_t, sizeof(client_encrypt_key_t)))
650 {
651 winpr_Digest_Free(sha1);
652 return FALSE;
653 }
654
655 client_encrypt_key_t[20] = client_encrypt_key_t[0];
656
657 if (!winpr_Digest_Init(sha1, WINPR_MD_SHA1) ||
658 !winpr_Digest_Update(sha1, client_random, 16) ||
659 !winpr_Digest_Update(sha1, server_random, 16) ||
660 !winpr_Digest_Final(sha1, client_decrypt_key_t, sizeof(client_decrypt_key_t)))
661 {
662 winpr_Digest_Free(sha1);
663 return FALSE;
664 }
665
666 client_decrypt_key_t[20] = client_decrypt_key_t[0];
667
668 if (!winpr_Digest_Init(sha1, WINPR_MD_SHA1) ||
669 !winpr_Digest_Update(sha1, client_decrypt_key_t, WINPR_SHA1_DIGEST_LENGTH) ||
670 !winpr_Digest_Update(sha1, client_encrypt_key_t, WINPR_SHA1_DIGEST_LENGTH) ||
671 !winpr_Digest_Final(sha1, rdp->fips_sign_key, WINPR_SHA1_DIGEST_LENGTH))
672 {
673 winpr_Digest_Free(sha1);
674 return FALSE;
675 }
676
677 winpr_Digest_Free(sha1);
678
679 if (settings->ServerMode)
680 {
681 fips_expand_key_bits(client_encrypt_key_t, sizeof(client_encrypt_key_t),
682 rdp->fips_decrypt_key, sizeof(rdp->fips_decrypt_key));
683 fips_expand_key_bits(client_decrypt_key_t, sizeof(client_decrypt_key_t),
684 rdp->fips_encrypt_key, sizeof(rdp->fips_encrypt_key));
685 }
686 else
687 {
688 fips_expand_key_bits(client_encrypt_key_t, sizeof(client_encrypt_key_t),
689 rdp->fips_encrypt_key, sizeof(rdp->fips_encrypt_key));
690 fips_expand_key_bits(client_decrypt_key_t, sizeof(client_decrypt_key_t),
691 rdp->fips_decrypt_key, sizeof(rdp->fips_decrypt_key));
692 }
693 }
694
695 memcpy(pre_master_secret, client_random, 24);
696 memcpy(pre_master_secret + 24, server_random, 24);
697
698 if (!security_A(pre_master_secret, sizeof(pre_master_secret), client_random, ClientRandomLength,
699 server_random, ServerRandomLength, master_secret, sizeof(master_secret)) ||
700 !security_X(master_secret, sizeof(master_secret), client_random, ClientRandomLength,
701 server_random, ServerRandomLength, session_key_blob, sizeof(session_key_blob)))
702 {
703 return FALSE;
704 }
705
706 memcpy(rdp->sign_key, session_key_blob, 16);
707
708 if (settings->ServerMode)
709 {
710 status = security_md5_16_32_32(&session_key_blob[16], client_random, server_random,
711 rdp->encrypt_key, sizeof(rdp->encrypt_key));
712 status &= security_md5_16_32_32(&session_key_blob[32], client_random, server_random,
713 rdp->decrypt_key, sizeof(rdp->decrypt_key));
714 }
715 else
716 {
717 /* Allow FIPS use of MD5 here, this is just used for generation of the SessionKeyBlob as
718 * described in MS-RDPELE. */
719 /* This is for RDP licensing packets which will already be encrypted under FIPS, so the use
720 * of MD5 here is not */
721 /* for sensitive data protection. */
722 status =
723 security_md5_16_32_32_Allow_FIPS(&session_key_blob[16], client_random, server_random,
724 rdp->decrypt_key, sizeof(rdp->decrypt_key));
725 status &=
726 security_md5_16_32_32_Allow_FIPS(&session_key_blob[32], client_random, server_random,
727 rdp->encrypt_key, sizeof(rdp->encrypt_key));
728 }
729
730 if (!status)
731 return FALSE;
732
733 if (settings->EncryptionMethods == ENCRYPTION_METHOD_40BIT)
734 {
735 memcpy(rdp->sign_key, salt, 3);
736 memcpy(rdp->decrypt_key, salt, 3);
737 memcpy(rdp->encrypt_key, salt, 3);
738 rdp->rc4_key_len = 8;
739 }
740 else if (settings->EncryptionMethods == ENCRYPTION_METHOD_56BIT)
741 {
742 memcpy(rdp->sign_key, salt, 1);
743 memcpy(rdp->decrypt_key, salt, 1);
744 memcpy(rdp->encrypt_key, salt, 1);
745 rdp->rc4_key_len = 8;
746 }
747 else if (settings->EncryptionMethods == ENCRYPTION_METHOD_128BIT)
748 {
749 rdp->rc4_key_len = 16;
750 }
751
752 if (!security_lock(rdp))
753 return FALSE;
754 memcpy(rdp->decrypt_update_key, rdp->decrypt_key, 16);
755 memcpy(rdp->encrypt_update_key, rdp->encrypt_key, 16);
756 rdp->decrypt_use_count = 0;
757 rdp->decrypt_checksum_use_count = 0;
758 rdp->encrypt_use_count = 0;
759 rdp->encrypt_checksum_use_count = 0;
760
761 return security_unlock(rdp);
762}
763
764static BOOL security_key_update(BYTE* key, BYTE* update_key, size_t key_len, rdpRdp* rdp)
765{
766 BYTE sha1h[WINPR_SHA1_DIGEST_LENGTH] = { 0 };
767 WINPR_DIGEST_CTX* sha1 = NULL;
768 WINPR_DIGEST_CTX* md5 = NULL;
769 WINPR_RC4_CTX* rc4 = NULL;
770 BYTE salt[] = { 0xD1, 0x26, 0x9E }; /* 40 bits: 3 bytes, 56 bits: 1 byte */
771 BOOL result = FALSE;
772 WLog_DBG(TAG, "updating RDP key");
773
774 if (!(sha1 = winpr_Digest_New()))
775 goto out;
776
777 if (!winpr_Digest_Init(sha1, WINPR_MD_SHA1))
778 goto out;
779
780 if (!winpr_Digest_Update(sha1, update_key, key_len))
781 goto out;
782
783 if (!winpr_Digest_Update(sha1, pad1, sizeof(pad1)))
784 goto out;
785
786 if (!winpr_Digest_Update(sha1, key, key_len))
787 goto out;
788
789 if (!winpr_Digest_Final(sha1, sha1h, sizeof(sha1h)))
790 goto out;
791
792 if (!(md5 = winpr_Digest_New()))
793 goto out;
794
795 if (!winpr_Digest_Init(md5, WINPR_MD_MD5))
796 goto out;
797
798 if (!winpr_Digest_Update(md5, update_key, key_len))
799 goto out;
800
801 if (!winpr_Digest_Update(md5, pad2, sizeof(pad2)))
802 goto out;
803
804 if (!winpr_Digest_Update(md5, sha1h, sizeof(sha1h)))
805 goto out;
806
807 if (!winpr_Digest_Final(md5, key, WINPR_MD5_DIGEST_LENGTH))
808 goto out;
809
810 if (!(rc4 = winpr_RC4_New(key, key_len)))
811 goto out;
812
813 if (!winpr_RC4_Update(rc4, key_len, key, key))
814 goto out;
815
816 if (rdp->settings->EncryptionMethods == ENCRYPTION_METHOD_40BIT)
817 memcpy(key, salt, 3);
818 else if (rdp->settings->EncryptionMethods == ENCRYPTION_METHOD_56BIT)
819 memcpy(key, salt, 1);
820
821 result = TRUE;
822out:
823 winpr_Digest_Free(sha1);
824 winpr_Digest_Free(md5);
825 winpr_RC4_Free(rc4);
826 return result;
827}
828
829BOOL security_encrypt(BYTE* data, size_t length, rdpRdp* rdp)
830{
831 BOOL rc = FALSE;
832
833 WINPR_ASSERT(rdp);
834 if (!rdp->rc4_encrypt_key)
835 {
836 WLog_ERR(TAG, "rdp->rc4_encrypt_key=%p", rdp->rc4_encrypt_key);
837 goto fail;
838 }
839
840 if (rdp->encrypt_use_count >= 4096)
841 {
842 if (!security_key_update(rdp->encrypt_key, rdp->encrypt_update_key, rdp->rc4_key_len, rdp))
843 goto fail;
844
845 if (!rdp_reset_rc4_encrypt_keys(rdp))
846 goto fail;
847 }
848
849 if (!winpr_RC4_Update(rdp->rc4_encrypt_key, length, data, data))
850 goto fail;
851
852 rdp->encrypt_use_count++;
853 rdp->encrypt_checksum_use_count++;
854 rc = TRUE;
855fail:
856 return rc;
857}
858
859BOOL security_decrypt(BYTE* data, size_t length, rdpRdp* rdp)
860{
861 BOOL rc = FALSE;
862
863 WINPR_ASSERT(data || (length == 0));
864 WINPR_ASSERT(rdp);
865
866 if (!rdp->rc4_decrypt_key)
867 {
868 WLog_ERR(TAG, "rdp->rc4_decrypt_key=%p", rdp->rc4_decrypt_key);
869 goto fail;
870 }
871
872 if (rdp->decrypt_use_count >= 4096)
873 {
874 if (!security_key_update(rdp->decrypt_key, rdp->decrypt_update_key, rdp->rc4_key_len, rdp))
875 goto fail;
876
877 if (!rdp_reset_rc4_decrypt_keys(rdp))
878 goto fail;
879 }
880
881 if (!winpr_RC4_Update(rdp->rc4_decrypt_key, length, data, data))
882 goto fail;
883
884 rdp->decrypt_use_count += 1;
885 rdp->decrypt_checksum_use_count++;
886 rc = TRUE;
887fail:
888 if (!rc)
889 WLog_WARN(TAG, "Failed to decrypt security");
890 return rc;
891}
892
893BOOL security_hmac_signature(const BYTE* data, size_t length, BYTE* output, size_t out_len,
894 rdpRdp* rdp)
895{
896 BYTE buf[WINPR_SHA1_DIGEST_LENGTH] = { 0 };
897 BYTE use_count_le[4] = { 0 };
898 WINPR_HMAC_CTX* hmac = NULL;
899 BOOL result = FALSE;
900
901 WINPR_ASSERT(rdp);
902 WINPR_ASSERT(output);
903 if (out_len < 8)
904 return FALSE;
905
906 security_UINT32_le(use_count_le, sizeof(use_count_le), rdp->encrypt_use_count);
907
908 if (!(hmac = winpr_HMAC_New()))
909 return FALSE;
910
911 if (!winpr_HMAC_Init(hmac, WINPR_MD_SHA1, rdp->fips_sign_key, WINPR_SHA1_DIGEST_LENGTH))
912 goto out;
913
914 if (!winpr_HMAC_Update(hmac, data, length))
915 goto out;
916
917 if (!winpr_HMAC_Update(hmac, use_count_le, 4))
918 goto out;
919
920 if (!winpr_HMAC_Final(hmac, buf, WINPR_SHA1_DIGEST_LENGTH))
921 goto out;
922
923 memmove(output, buf, 8);
924 result = TRUE;
925out:
926 winpr_HMAC_Free(hmac);
927 return result;
928}
929
930BOOL security_fips_encrypt(BYTE* data, size_t length, rdpRdp* rdp)
931{
932 BOOL rc = FALSE;
933 size_t olen = 0;
934
935 if (!winpr_Cipher_Update(rdp->fips_encrypt, data, length, data, &olen))
936 goto fail;
937
938 rdp->encrypt_use_count++;
939 rc = TRUE;
940fail:
941 return rc;
942}
943
944BOOL security_fips_decrypt(BYTE* data, size_t length, rdpRdp* rdp)
945{
946 size_t olen = 0;
947
948 if (!rdp || !rdp->fips_decrypt)
949 {
950 WLog_ERR(TAG, "rdp=%p, rdp->fips_decrypt=%p", rdp, rdp ? rdp->fips_decrypt : NULL);
951 return FALSE;
952 }
953
954 if (!winpr_Cipher_Update(rdp->fips_decrypt, data, length, data, &olen))
955 return FALSE;
956
957 return TRUE;
958}
959
960BOOL security_fips_check_signature(const BYTE* data, size_t length, const BYTE* sig, size_t sig_len,
961 rdpRdp* rdp)
962{
963 BYTE buf[WINPR_SHA1_DIGEST_LENGTH] = { 0 };
964 BYTE use_count_le[4] = { 0 };
965 WINPR_HMAC_CTX* hmac = NULL;
966 BOOL result = FALSE;
967
968 security_UINT32_le(use_count_le, sizeof(use_count_le), rdp->decrypt_use_count++);
969
970 if (!(hmac = winpr_HMAC_New()))
971 goto out;
972
973 if (!winpr_HMAC_Init(hmac, WINPR_MD_SHA1, rdp->fips_sign_key, WINPR_SHA1_DIGEST_LENGTH))
974 goto out;
975
976 if (!winpr_HMAC_Update(hmac, data, length))
977 goto out;
978
979 if (!winpr_HMAC_Update(hmac, use_count_le, 4))
980 goto out;
981
982 if (!winpr_HMAC_Final(hmac, buf, WINPR_SHA1_DIGEST_LENGTH))
983 goto out;
984
985 if ((sig_len >= 8) && (memcmp(sig, buf, 8) == 0))
986 result = TRUE;
987
988out:
989 if (!result)
990 WLog_WARN(TAG, "signature check failed");
991 winpr_HMAC_Free(hmac);
992 return result;
993}
994
995BOOL security_lock(rdpRdp* rdp)
996{
997 WINPR_ASSERT(rdp);
998 EnterCriticalSection(&rdp->critical);
999 return TRUE;
1000}
1001
1002BOOL security_unlock(rdpRdp* rdp)
1003{
1004 WINPR_ASSERT(rdp);
1005 LeaveCriticalSection(&rdp->critical);
1006 return TRUE;
1007}
freerdp_settings_get_uint32
FREERDP_API UINT32 freerdp_settings_get_uint32(const rdpSettings *settings, FreeRDP_Settings_Keys_UInt32 id)
Returns a UINT32 settings value.
freerdp_settings_get_pointer
FREERDP_API const void * freerdp_settings_get_pointer(const rdpSettings *settings, FreeRDP_Settings_Keys_Pointer id)
Returns a immutable pointer settings value.
Definition common/settings.c:1332