2 * chap_ms.c - Microsoft MS-CHAP compatible implementation.
4 * Copyright (c) 1995 Eric Rosenquist, Strata Software Limited.
5 * http://www.strataware.com/
9 * Redistribution and use in source and binary forms are permitted
10 * provided that the above copyright notice and this paragraph are
11 * duplicated in all such forms and that any documentation,
12 * advertising materials, and other materials related to such
13 * distribution and use acknowledge that the software was developed
14 * by Eric Rosenquist. The name of the author may not be used to
15 * endorse or promote products derived from this software without
16 * specific prior written permission.
18 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
20 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
24 * Modifications by Lauri Pesonen / lpesonen@clinet.fi, april 1997
26 * Implemented LANManager type password response to MS-CHAP challenges.
27 * Now pppd provides both NT style and LANMan style blocks, and the
28 * prefered is set by option "ms-lanman". Default is to use NT.
29 * The hash text (StdText) was taken from Win95 RASAPI32.DLL.
31 * You should also use DOMAIN\\USERNAME as described in README.MSCHAP80
35 static char rcsid[] = "$Id: chap_ms.c,v 1.7 1998/03/25 03:08:14 paulus Exp $";
43 #include <sys/types.h>
61 u_char LANManResp[24];
63 u_char UseNT; /* If 1, ignore the LANMan response field */
65 /* We use MS_CHAP_RESPONSE_LEN, rather than sizeof(MS_ChapResponse),
66 in case this struct gets padded. */
69 static void ChallengeResponse __P((u_char *, u_char *, u_char *));
70 static void DesEncrypt __P((u_char *, u_char *, u_char *));
71 static void MakeKey __P((u_char *, u_char *));
72 static u_char Get7Bits __P((u_char *, int));
73 static void ChapMS_NT __P((char *, int, char *, int, MS_ChapResponse *));
75 static void ChapMS_LANMan __P((char *, int, char *, int, MS_ChapResponse *));
79 static void Expand __P((u_char *, u_char *));
80 static void Collapse __P((u_char *, u_char *));
84 ChallengeResponse(challenge, pwHash, response)
85 u_char *challenge; /* IN 8 octets */
86 u_char *pwHash; /* IN 16 octets */
87 u_char *response; /* OUT 24 octets */
89 char ZPasswordHash[21];
91 BZERO(ZPasswordHash, sizeof(ZPasswordHash));
92 BCOPY(pwHash, ZPasswordHash, MD4_SIGNATURE_SIZE);
95 log_packet(ZPasswordHash, sizeof(ZPasswordHash), "ChallengeResponse - ZPasswordHash", LOG_DEBUG);
98 DesEncrypt(challenge, ZPasswordHash + 0, response + 0);
99 DesEncrypt(challenge, ZPasswordHash + 7, response + 8);
100 DesEncrypt(challenge, ZPasswordHash + 14, response + 16);
103 log_packet(response, 24, "ChallengeResponse - response", LOG_DEBUG);
110 DesEncrypt(clear, key, cipher)
111 u_char *clear; /* IN 8 octets */
112 u_char *key; /* IN 7 octets */
113 u_char *cipher; /* OUT 8 octets */
116 u_char crypt_key[66];
117 u_char des_input[66];
119 MakeKey(key, des_key);
121 Expand(des_key, crypt_key);
125 CHAPDEBUG((LOG_INFO, "DesEncrypt: 8 octet input : %02X%02X%02X%02X%02X%02X%02X%02X",
126 clear[0], clear[1], clear[2], clear[3], clear[4], clear[5], clear[6], clear[7]));
129 Expand(clear, des_input);
130 encrypt(des_input, 0);
131 Collapse(des_input, cipher);
134 CHAPDEBUG((LOG_INFO, "DesEncrypt: 8 octet output: %02X%02X%02X%02X%02X%02X%02X%02X",
135 cipher[0], cipher[1], cipher[2], cipher[3], cipher[4], cipher[5], cipher[6], cipher[7]));
139 #else /* USE_CRYPT */
142 DesEncrypt(clear, key, cipher)
143 u_char *clear; /* IN 8 octets */
144 u_char *key; /* IN 7 octets */
145 u_char *cipher; /* OUT 8 octets */
148 des_key_schedule key_schedule;
150 MakeKey(key, des_key);
152 des_set_key(&des_key, key_schedule);
155 CHAPDEBUG((LOG_INFO, "DesEncrypt: 8 octet input : %02X%02X%02X%02X%02X%02X%02X%02X",
156 clear[0], clear[1], clear[2], clear[3], clear[4], clear[5], clear[6], clear[7]));
159 des_ecb_encrypt((des_cblock *)clear, (des_cblock *)cipher, key_schedule, 1);
162 CHAPDEBUG((LOG_INFO, "DesEncrypt: 8 octet output: %02X%02X%02X%02X%02X%02X%02X%02X",
163 cipher[0], cipher[1], cipher[2], cipher[3], cipher[4], cipher[5], cipher[6], cipher[7]));
167 #endif /* USE_CRYPT */
170 static u_char Get7Bits(input, startBit)
174 register unsigned int word;
176 word = (unsigned)input[startBit / 8] << 8;
177 word |= (unsigned)input[startBit / 8 + 1];
179 word >>= 15 - (startBit % 8 + 7);
186 /* in == 8-byte string (expanded version of the 56-bit key)
187 * out == 64-byte string where each byte is either 1 or 0
188 * Note that the low-order "bit" is always ignored by by setkey()
190 static void Expand(in, out)
197 for(i = 0; i < 64; in++){
199 for(j = 7; j >= 0; j--)
200 *out++ = (c >> j) & 01;
205 /* The inverse of Expand
207 static void Collapse(in, out)
215 for (i = 0; i < 64; i += 8, out++) {
217 for (j = 7; j >= 0; j--, in++)
224 static void MakeKey(key, des_key)
225 u_char *key; /* IN 56 bit DES key missing parity bits */
226 u_char *des_key; /* OUT 64 bit DES key with parity bits added */
228 des_key[0] = Get7Bits(key, 0);
229 des_key[1] = Get7Bits(key, 7);
230 des_key[2] = Get7Bits(key, 14);
231 des_key[3] = Get7Bits(key, 21);
232 des_key[4] = Get7Bits(key, 28);
233 des_key[5] = Get7Bits(key, 35);
234 des_key[6] = Get7Bits(key, 42);
235 des_key[7] = Get7Bits(key, 49);
238 des_set_odd_parity((des_cblock *)des_key);
242 CHAPDEBUG((LOG_INFO, "MakeKey: 56-bit input : %02X%02X%02X%02X%02X%02X%02X",
243 key[0], key[1], key[2], key[3], key[4], key[5], key[6]));
244 CHAPDEBUG((LOG_INFO, "MakeKey: 64-bit output: %02X%02X%02X%02X%02X%02X%02X%02X",
245 des_key[0], des_key[1], des_key[2], des_key[3], des_key[4], des_key[5], des_key[6], des_key[7]));
250 ChapMS_NT(rchallenge, rchallenge_len, secret, secret_len, response)
255 MS_ChapResponse *response;
259 u_char hash[MD4_SIGNATURE_SIZE];
260 u_char unicodePassword[MAX_NT_PASSWORD * 2];
262 /* Initialize the Unicode version of the secret (== password). */
263 /* This implicitly supports 8-bit ISO8859/1 characters. */
264 BZERO(unicodePassword, sizeof(unicodePassword));
265 for (i = 0; i < secret_len; i++)
266 unicodePassword[i * 2] = (u_char)secret[i];
268 MD4Init(&md4Context);
269 MD4Update(&md4Context, unicodePassword, secret_len * 2 * 8); /* Unicode is 2 bytes/char, *8 for bit count */
271 MD4Final(hash, &md4Context); /* Tell MD4 we're done */
273 ChallengeResponse(rchallenge, hash, response->NTResp);
277 static u_char *StdText = (u_char *)"KGS!@#$%"; /* key from rasapi32.dll */
280 ChapMS_LANMan(rchallenge, rchallenge_len, secret, secret_len, response)
285 MS_ChapResponse *response;
288 u_char UcasePassword[MAX_NT_PASSWORD]; /* max is actually 14 */
289 u_char PasswordHash[MD4_SIGNATURE_SIZE];
291 /* LANMan password is case insensitive */
292 BZERO(UcasePassword, sizeof(UcasePassword));
293 for (i = 0; i < secret_len; i++)
294 UcasePassword[i] = (u_char)toupper(secret[i]);
295 DesEncrypt( StdText, UcasePassword + 0, PasswordHash + 0 );
296 DesEncrypt( StdText, UcasePassword + 7, PasswordHash + 8 );
297 ChallengeResponse(rchallenge, PasswordHash, response->LANManResp);
302 ChapMS(cstate, rchallenge, rchallenge_len, secret, secret_len)
309 MS_ChapResponse response;
311 extern int ms_lanman;
315 CHAPDEBUG((LOG_INFO, "ChapMS: secret is '%.*s'", secret_len, secret));
317 BZERO(&response, sizeof(response));
319 /* Calculate both always */
320 ChapMS_NT(rchallenge, rchallenge_len, secret, secret_len, &response);
323 ChapMS_LANMan(rchallenge, rchallenge_len, secret, secret_len, &response);
325 /* prefered method is set by option */
326 response.UseNT = !ms_lanman;
331 BCOPY(&response, cstate->response, MS_CHAP_RESPONSE_LEN);
332 cstate->resp_length = MS_CHAP_RESPONSE_LEN;