1 /*
2 * WPA Supplicant / shared MSCHAPV2 helper functions / RFC 2433 / RFC 2759
3 * Copyright (c) 2004-2012, Jouni Malinen <j@w1.fi>
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9 #include "includes.h"
10
11 #include "common.h"
12 #include "sha1.h"
13 #include "ms_funcs.h"
14 #include "crypto.h"
15
16 /**
17 * utf8_to_ucs2 - Convert UTF-8 string to UCS-2 encoding
18 * @utf8_string: UTF-8 string (IN)
19 * @utf8_string_len: Length of utf8_string (IN)
20 * @ucs2_buffer: UCS-2 buffer (OUT)
21 * @ucs2_buffer_size: Length of UCS-2 buffer (IN)
22 * @ucs2_string_size: Number of 2-byte words in the resulting UCS-2 string
23 * Returns: 0 on success, -1 on failure
24 */
utf8_to_ucs2(const u8 * utf8_string,size_t utf8_string_len,u8 * ucs2_buffer,size_t ucs2_buffer_size,size_t * ucs2_string_size)25 static int utf8_to_ucs2(const u8 *utf8_string, size_t utf8_string_len,
26 u8 *ucs2_buffer, size_t ucs2_buffer_size,
27 size_t *ucs2_string_size)
28 {
29 size_t i, j;
30
31 for (i = 0, j = 0; i < utf8_string_len; i++) {
32 u8 c = utf8_string[i];
33 if (j >= ucs2_buffer_size) {
34 /* input too long */
35 return -1;
36 }
37 if (c <= 0x7F) {
38 WPA_PUT_LE16(ucs2_buffer + j, c);
39 j += 2;
40 } else if (i == utf8_string_len - 1 ||
41 j >= ucs2_buffer_size - 1) {
42 /* incomplete surrogate */
43 return -1;
44 } else {
45 u8 c2 = utf8_string[++i];
46 if ((c & 0xE0) == 0xC0) {
47 /* two-byte encoding */
48 WPA_PUT_LE16(ucs2_buffer + j,
49 ((c & 0x1F) << 6) | (c2 & 0x3F));
50 j += 2;
51 } else if (i == utf8_string_len - 1 ||
52 j >= ucs2_buffer_size - 1) {
53 /* incomplete surrogate */
54 return -1;
55 } else {
56 /* three-byte encoding */
57 u8 c3 = utf8_string[++i];
58 WPA_PUT_LE16(ucs2_buffer + j,
59 ((c & 0xF) << 12) |
60 ((c2 & 0x3F) << 6) | (c3 & 0x3F));
61 j += 2;
62 }
63 }
64 }
65
66 if (ucs2_string_size)
67 *ucs2_string_size = j / 2;
68 return 0;
69 }
70
71
72 /**
73 * challenge_hash - ChallengeHash() - RFC 2759, Sect. 8.2
74 * @peer_challenge: 16-octet PeerChallenge (IN)
75 * @auth_challenge: 16-octet AuthenticatorChallenge (IN)
76 * @username: 0-to-256-char UserName (IN)
77 * @username_len: Length of username
78 * @challenge: 8-octet Challenge (OUT)
79 * Returns: 0 on success, -1 on failure
80 */
challenge_hash(const u8 * peer_challenge,const u8 * auth_challenge,const u8 * username,size_t username_len,u8 * challenge)81 int challenge_hash(const u8 *peer_challenge, const u8 *auth_challenge,
82 const u8 *username, size_t username_len, u8 *challenge)
83 {
84 u8 hash[SHA1_MAC_LEN];
85 const unsigned char *addr[3];
86 size_t len[3];
87
88 addr[0] = peer_challenge;
89 len[0] = 16;
90 addr[1] = auth_challenge;
91 len[1] = 16;
92 addr[2] = username;
93 len[2] = username_len;
94
95 if (sha1_vector(3, addr, len, hash))
96 return -1;
97 os_memcpy(challenge, hash, 8);
98 return 0;
99 }
100
101
102 /**
103 * nt_password_hash - NtPasswordHash() - RFC 2759, Sect. 8.3
104 * @password: 0-to-256-unicode-char Password (IN; UTF-8)
105 * @password_len: Length of password
106 * @password_hash: 16-octet PasswordHash (OUT)
107 * Returns: 0 on success, -1 on failure
108 */
nt_password_hash(const u8 * password,size_t password_len,u8 * password_hash)109 int nt_password_hash(const u8 *password, size_t password_len,
110 u8 *password_hash)
111 {
112 u8 buf[512], *pos;
113 size_t len, max_len;
114
115 max_len = sizeof(buf);
116 if (utf8_to_ucs2(password, password_len, buf, max_len, &len) < 0)
117 return -1;
118
119 len *= 2;
120 pos = buf;
121 return md4_vector(1, (const u8 **) &pos, &len, password_hash);
122 }
123
124
125 /**
126 * hash_nt_password_hash - HashNtPasswordHash() - RFC 2759, Sect. 8.4
127 * @password_hash: 16-octet PasswordHash (IN)
128 * @password_hash_hash: 16-octet PasswordHashHash (OUT)
129 * Returns: 0 on success, -1 on failure
130 */
hash_nt_password_hash(const u8 * password_hash,u8 * password_hash_hash)131 int hash_nt_password_hash(const u8 *password_hash, u8 *password_hash_hash)
132 {
133 size_t len = 16;
134 return md4_vector(1, &password_hash, &len, password_hash_hash);
135 }
136
137
138 /**
139 * challenge_response - ChallengeResponse() - RFC 2759, Sect. 8.5
140 * @challenge: 8-octet Challenge (IN)
141 * @password_hash: 16-octet PasswordHash (IN)
142 * @response: 24-octet Response (OUT)
143 */
challenge_response(const u8 * challenge,const u8 * password_hash,u8 * response)144 void challenge_response(const u8 *challenge, const u8 *password_hash,
145 u8 *response)
146 {
147 u8 zpwd[7];
148 des_encrypt(challenge, password_hash, response);
149 des_encrypt(challenge, password_hash + 7, response + 8);
150 zpwd[0] = password_hash[14];
151 zpwd[1] = password_hash[15];
152 os_memset(zpwd + 2, 0, 5);
153 des_encrypt(challenge, zpwd, response + 16);
154 }
155
156
157 /**
158 * generate_nt_response - GenerateNTResponse() - RFC 2759, Sect. 8.1
159 * @auth_challenge: 16-octet AuthenticatorChallenge (IN)
160 * @peer_challenge: 16-octet PeerChallenge (IN)
161 * @username: 0-to-256-char UserName (IN)
162 * @username_len: Length of username
163 * @password: 0-to-256-unicode-char Password (IN; UTF-8)
164 * @password_len: Length of password
165 * @response: 24-octet Response (OUT)
166 * Returns: 0 on success, -1 on failure
167 */
generate_nt_response(const u8 * auth_challenge,const u8 * peer_challenge,const u8 * username,size_t username_len,const u8 * password,size_t password_len,u8 * response)168 int generate_nt_response(const u8 *auth_challenge, const u8 *peer_challenge,
169 const u8 *username, size_t username_len,
170 const u8 *password, size_t password_len,
171 u8 *response)
172 {
173 u8 challenge[8];
174 u8 password_hash[16];
175
176 if (challenge_hash(peer_challenge, auth_challenge, username,
177 username_len, challenge) ||
178 nt_password_hash(password, password_len, password_hash))
179 return -1;
180 challenge_response(challenge, password_hash, response);
181 return 0;
182 }
183
184
185 /**
186 * generate_nt_response_pwhash - GenerateNTResponse() - RFC 2759, Sect. 8.1
187 * @auth_challenge: 16-octet AuthenticatorChallenge (IN)
188 * @peer_challenge: 16-octet PeerChallenge (IN)
189 * @username: 0-to-256-char UserName (IN)
190 * @username_len: Length of username
191 * @password_hash: 16-octet PasswordHash (IN)
192 * @response: 24-octet Response (OUT)
193 * Returns: 0 on success, -1 on failure
194 */
generate_nt_response_pwhash(const u8 * auth_challenge,const u8 * peer_challenge,const u8 * username,size_t username_len,const u8 * password_hash,u8 * response)195 int generate_nt_response_pwhash(const u8 *auth_challenge,
196 const u8 *peer_challenge,
197 const u8 *username, size_t username_len,
198 const u8 *password_hash,
199 u8 *response)
200 {
201 u8 challenge[8];
202
203 if (challenge_hash(peer_challenge, auth_challenge,
204 username, username_len,
205 challenge))
206 return -1;
207 challenge_response(challenge, password_hash, response);
208 return 0;
209 }
210
211
212 /**
213 * generate_authenticator_response_pwhash - GenerateAuthenticatorResponse() - RFC 2759, Sect. 8.7
214 * @password_hash: 16-octet PasswordHash (IN)
215 * @nt_response: 24-octet NT-Response (IN)
216 * @peer_challenge: 16-octet PeerChallenge (IN)
217 * @auth_challenge: 16-octet AuthenticatorChallenge (IN)
218 * @username: 0-to-256-char UserName (IN)
219 * @username_len: Length of username
220 * @response: 20-octet AuthenticatorResponse (OUT) (note: this value is usually
221 * encoded as a 42-octet ASCII string (S=hexdump_of_response)
222 * Returns: 0 on success, -1 on failure
223 */
generate_authenticator_response_pwhash(const u8 * password_hash,const u8 * peer_challenge,const u8 * auth_challenge,const u8 * username,size_t username_len,const u8 * nt_response,u8 * response)224 int generate_authenticator_response_pwhash(
225 const u8 *password_hash,
226 const u8 *peer_challenge, const u8 *auth_challenge,
227 const u8 *username, size_t username_len,
228 const u8 *nt_response, u8 *response)
229 {
230 static const u8 magic1[39] = {
231 0x4D, 0x61, 0x67, 0x69, 0x63, 0x20, 0x73, 0x65, 0x72, 0x76,
232 0x65, 0x72, 0x20, 0x74, 0x6F, 0x20, 0x63, 0x6C, 0x69, 0x65,
233 0x6E, 0x74, 0x20, 0x73, 0x69, 0x67, 0x6E, 0x69, 0x6E, 0x67,
234 0x20, 0x63, 0x6F, 0x6E, 0x73, 0x74, 0x61, 0x6E, 0x74
235 };
236 static const u8 magic2[41] = {
237 0x50, 0x61, 0x64, 0x20, 0x74, 0x6F, 0x20, 0x6D, 0x61, 0x6B,
238 0x65, 0x20, 0x69, 0x74, 0x20, 0x64, 0x6F, 0x20, 0x6D, 0x6F,
239 0x72, 0x65, 0x20, 0x74, 0x68, 0x61, 0x6E, 0x20, 0x6F, 0x6E,
240 0x65, 0x20, 0x69, 0x74, 0x65, 0x72, 0x61, 0x74, 0x69, 0x6F,
241 0x6E
242 };
243
244 u8 password_hash_hash[16], challenge[8];
245 const unsigned char *addr1[3];
246 const size_t len1[3] = { 16, 24, sizeof(magic1) };
247 const unsigned char *addr2[3];
248 const size_t len2[3] = { SHA1_MAC_LEN, 8, sizeof(magic2) };
249
250 addr1[0] = password_hash_hash;
251 addr1[1] = nt_response;
252 addr1[2] = magic1;
253
254 addr2[0] = response;
255 addr2[1] = challenge;
256 addr2[2] = magic2;
257
258 if (hash_nt_password_hash(password_hash, password_hash_hash) ||
259 sha1_vector(3, addr1, len1, response) ||
260 challenge_hash(peer_challenge, auth_challenge, username,
261 username_len, challenge))
262 return -1;
263 return sha1_vector(3, addr2, len2, response);
264 }
265
266
267 /**
268 * generate_authenticator_response - GenerateAuthenticatorResponse() - RFC 2759, Sect. 8.7
269 * @password: 0-to-256-unicode-char Password (IN; UTF-8)
270 * @password_len: Length of password
271 * @nt_response: 24-octet NT-Response (IN)
272 * @peer_challenge: 16-octet PeerChallenge (IN)
273 * @auth_challenge: 16-octet AuthenticatorChallenge (IN)
274 * @username: 0-to-256-char UserName (IN)
275 * @username_len: Length of username
276 * @response: 20-octet AuthenticatorResponse (OUT) (note: this value is usually
277 * encoded as a 42-octet ASCII string (S=hexdump_of_response)
278 * Returns: 0 on success, -1 on failure
279 */
generate_authenticator_response(const u8 * password,size_t password_len,const u8 * peer_challenge,const u8 * auth_challenge,const u8 * username,size_t username_len,const u8 * nt_response,u8 * response)280 int generate_authenticator_response(const u8 *password, size_t password_len,
281 const u8 *peer_challenge,
282 const u8 *auth_challenge,
283 const u8 *username, size_t username_len,
284 const u8 *nt_response, u8 *response)
285 {
286 u8 password_hash[16];
287 if (nt_password_hash(password, password_len, password_hash))
288 return -1;
289 return generate_authenticator_response_pwhash(
290 password_hash, peer_challenge, auth_challenge,
291 username, username_len, nt_response, response);
292 }
293
294
295 /**
296 * nt_challenge_response - NtChallengeResponse() - RFC 2433, Sect. A.5
297 * @challenge: 8-octet Challenge (IN)
298 * @password: 0-to-256-unicode-char Password (IN; UTF-8)
299 * @password_len: Length of password
300 * @response: 24-octet Response (OUT)
301 * Returns: 0 on success, -1 on failure
302 */
nt_challenge_response(const u8 * challenge,const u8 * password,size_t password_len,u8 * response)303 int nt_challenge_response(const u8 *challenge, const u8 *password,
304 size_t password_len, u8 *response)
305 {
306 u8 password_hash[16];
307 if (nt_password_hash(password, password_len, password_hash))
308 return -1;
309 challenge_response(challenge, password_hash, response);
310 return 0;
311 }
312
313
314 /**
315 * get_master_key - GetMasterKey() - RFC 3079, Sect. 3.4
316 * @password_hash_hash: 16-octet PasswordHashHash (IN)
317 * @nt_response: 24-octet NTResponse (IN)
318 * @master_key: 16-octet MasterKey (OUT)
319 * Returns: 0 on success, -1 on failure
320 */
get_master_key(const u8 * password_hash_hash,const u8 * nt_response,u8 * master_key)321 int get_master_key(const u8 *password_hash_hash, const u8 *nt_response,
322 u8 *master_key)
323 {
324 static const u8 magic1[27] = {
325 0x54, 0x68, 0x69, 0x73, 0x20, 0x69, 0x73, 0x20, 0x74,
326 0x68, 0x65, 0x20, 0x4d, 0x50, 0x50, 0x45, 0x20, 0x4d,
327 0x61, 0x73, 0x74, 0x65, 0x72, 0x20, 0x4b, 0x65, 0x79
328 };
329 const unsigned char *addr[3];
330 const size_t len[3] = { 16, 24, sizeof(magic1) };
331 u8 hash[SHA1_MAC_LEN];
332
333 addr[0] = password_hash_hash;
334 addr[1] = nt_response;
335 addr[2] = magic1;
336
337 if (sha1_vector(3, addr, len, hash))
338 return -1;
339 os_memcpy(master_key, hash, 16);
340 return 0;
341 }
342
343
344 /**
345 * get_asymetric_start_key - GetAsymetricStartKey() - RFC 3079, Sect. 3.4
346 * @master_key: 16-octet MasterKey (IN)
347 * @session_key: 8-to-16 octet SessionKey (OUT)
348 * @session_key_len: SessionKeyLength (Length of session_key) (IN)
349 * @is_send: IsSend (IN, BOOLEAN)
350 * @is_server: IsServer (IN, BOOLEAN)
351 * Returns: 0 on success, -1 on failure
352 */
get_asymetric_start_key(const u8 * master_key,u8 * session_key,size_t session_key_len,int is_send,int is_server)353 int get_asymetric_start_key(const u8 *master_key, u8 *session_key,
354 size_t session_key_len, int is_send,
355 int is_server)
356 {
357 static const u8 magic2[84] = {
358 0x4f, 0x6e, 0x20, 0x74, 0x68, 0x65, 0x20, 0x63, 0x6c, 0x69,
359 0x65, 0x6e, 0x74, 0x20, 0x73, 0x69, 0x64, 0x65, 0x2c, 0x20,
360 0x74, 0x68, 0x69, 0x73, 0x20, 0x69, 0x73, 0x20, 0x74, 0x68,
361 0x65, 0x20, 0x73, 0x65, 0x6e, 0x64, 0x20, 0x6b, 0x65, 0x79,
362 0x3b, 0x20, 0x6f, 0x6e, 0x20, 0x74, 0x68, 0x65, 0x20, 0x73,
363 0x65, 0x72, 0x76, 0x65, 0x72, 0x20, 0x73, 0x69, 0x64, 0x65,
364 0x2c, 0x20, 0x69, 0x74, 0x20, 0x69, 0x73, 0x20, 0x74, 0x68,
365 0x65, 0x20, 0x72, 0x65, 0x63, 0x65, 0x69, 0x76, 0x65, 0x20,
366 0x6b, 0x65, 0x79, 0x2e
367 };
368 static const u8 magic3[84] = {
369 0x4f, 0x6e, 0x20, 0x74, 0x68, 0x65, 0x20, 0x63, 0x6c, 0x69,
370 0x65, 0x6e, 0x74, 0x20, 0x73, 0x69, 0x64, 0x65, 0x2c, 0x20,
371 0x74, 0x68, 0x69, 0x73, 0x20, 0x69, 0x73, 0x20, 0x74, 0x68,
372 0x65, 0x20, 0x72, 0x65, 0x63, 0x65, 0x69, 0x76, 0x65, 0x20,
373 0x6b, 0x65, 0x79, 0x3b, 0x20, 0x6f, 0x6e, 0x20, 0x74, 0x68,
374 0x65, 0x20, 0x73, 0x65, 0x72, 0x76, 0x65, 0x72, 0x20, 0x73,
375 0x69, 0x64, 0x65, 0x2c, 0x20, 0x69, 0x74, 0x20, 0x69, 0x73,
376 0x20, 0x74, 0x68, 0x65, 0x20, 0x73, 0x65, 0x6e, 0x64, 0x20,
377 0x6b, 0x65, 0x79, 0x2e
378 };
379 static const u8 shs_pad1[40] = {
380 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
381 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
382 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
383 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
384 };
385
386 static const u8 shs_pad2[40] = {
387 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2,
388 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2,
389 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2,
390 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2, 0xf2
391 };
392 u8 digest[SHA1_MAC_LEN];
393 const unsigned char *addr[4];
394 const size_t len[4] = { 16, 40, 84, 40 };
395
396 addr[0] = master_key;
397 addr[1] = shs_pad1;
398 if (is_send) {
399 addr[2] = is_server ? magic3 : magic2;
400 } else {
401 addr[2] = is_server ? magic2 : magic3;
402 }
403 addr[3] = shs_pad2;
404
405 if (sha1_vector(4, addr, len, digest))
406 return -1;
407
408 if (session_key_len > SHA1_MAC_LEN)
409 session_key_len = SHA1_MAC_LEN;
410 os_memcpy(session_key, digest, session_key_len);
411 return 0;
412 }
413
414
415 #ifndef CONFIG_NO_RC4
416
417 #define PWBLOCK_LEN 516
418
419 /**
420 * encrypt_pw_block_with_password_hash - EncryptPwBlockWithPasswordHash() - RFC 2759, Sect. 8.10
421 * @password: 0-to-256-unicode-char Password (IN; UTF-8)
422 * @password_len: Length of password
423 * @password_hash: 16-octet PasswordHash (IN)
424 * @pw_block: 516-byte PwBlock (OUT)
425 * Returns: 0 on success, -1 on failure
426 */
encrypt_pw_block_with_password_hash(const u8 * password,size_t password_len,const u8 * password_hash,u8 * pw_block)427 int encrypt_pw_block_with_password_hash(
428 const u8 *password, size_t password_len,
429 const u8 *password_hash, u8 *pw_block)
430 {
431 size_t ucs2_len, offset;
432 u8 *pos;
433
434 os_memset(pw_block, 0, PWBLOCK_LEN);
435
436 if (utf8_to_ucs2(password, password_len, pw_block, 512, &ucs2_len) < 0
437 || ucs2_len > 256)
438 return -1;
439
440 offset = (256 - ucs2_len) * 2;
441 if (offset != 0) {
442 os_memmove(pw_block + offset, pw_block, ucs2_len * 2);
443 if (os_get_random(pw_block, offset) < 0)
444 return -1;
445 }
446 /*
447 * PasswordLength is 4 octets, but since the maximum password length is
448 * 256, only first two (in little endian byte order) can be non-zero.
449 */
450 pos = &pw_block[2 * 256];
451 WPA_PUT_LE16(pos, password_len * 2);
452 rc4_skip(password_hash, 16, 0, pw_block, PWBLOCK_LEN);
453 return 0;
454 }
455
456
457 /**
458 * new_password_encrypted_with_old_nt_password_hash - NewPasswordEncryptedWithOldNtPasswordHash() - RFC 2759, Sect. 8.9
459 * @new_password: 0-to-256-unicode-char NewPassword (IN; UTF-8)
460 * @new_password_len: Length of new_password
461 * @old_password: 0-to-256-unicode-char OldPassword (IN; UTF-8)
462 * @old_password_len: Length of old_password
463 * @encrypted_pw_block: 516-octet EncryptedPwBlock (OUT)
464 * Returns: 0 on success, -1 on failure
465 */
new_password_encrypted_with_old_nt_password_hash(const u8 * new_password,size_t new_password_len,const u8 * old_password,size_t old_password_len,u8 * encrypted_pw_block)466 int new_password_encrypted_with_old_nt_password_hash(
467 const u8 *new_password, size_t new_password_len,
468 const u8 *old_password, size_t old_password_len,
469 u8 *encrypted_pw_block)
470 {
471 u8 password_hash[16];
472
473 if (nt_password_hash(old_password, old_password_len, password_hash))
474 return -1;
475 if (encrypt_pw_block_with_password_hash(new_password, new_password_len,
476 password_hash,
477 encrypted_pw_block))
478 return -1;
479 return 0;
480 }
481
482 #endif /* CONFIG_NO_RC4 */
483
484
485 /**
486 * nt_password_hash_encrypted_with_block - NtPasswordHashEncryptedWithBlock() - RFC 2759, Sect 8.13
487 * @password_hash: 16-octer PasswordHash (IN)
488 * @block: 16-octet Block (IN)
489 * @cypher: 16-octer Cypher (OUT)
490 */
nt_password_hash_encrypted_with_block(const u8 * password_hash,const u8 * block,u8 * cypher)491 void nt_password_hash_encrypted_with_block(const u8 *password_hash,
492 const u8 *block, u8 *cypher)
493 {
494 des_encrypt(password_hash, block, cypher);
495 des_encrypt(password_hash + 8, block + 7, cypher + 8);
496 }
497
498
499 /**
500 * old_nt_password_hash_encrypted_with_new_nt_password_hash - OldNtPasswordHashEncryptedWithNewNtPasswordHash() - RFC 2759, Sect. 8.12
501 * @new_password: 0-to-256-unicode-char NewPassword (IN; UTF-8)
502 * @new_password_len: Length of new_password
503 * @old_password: 0-to-256-unicode-char OldPassword (IN; UTF-8)
504 * @old_password_len: Length of old_password
505 * @encrypted_password_hash: 16-octet EncryptedPasswordHash (OUT)
506 * Returns: 0 on success, -1 on failure
507 */
old_nt_password_hash_encrypted_with_new_nt_password_hash(const u8 * new_password,size_t new_password_len,const u8 * old_password,size_t old_password_len,u8 * encrypted_password_hash)508 int old_nt_password_hash_encrypted_with_new_nt_password_hash(
509 const u8 *new_password, size_t new_password_len,
510 const u8 *old_password, size_t old_password_len,
511 u8 *encrypted_password_hash)
512 {
513 u8 old_password_hash[16], new_password_hash[16];
514
515 if (nt_password_hash(old_password, old_password_len,
516 old_password_hash) ||
517 nt_password_hash(new_password, new_password_len,
518 new_password_hash))
519 return -1;
520 nt_password_hash_encrypted_with_block(old_password_hash,
521 new_password_hash,
522 encrypted_password_hash);
523 return 0;
524 }
525