xref: /netbsd-src/external/bsd/openldap/dist/contrib/slapd-modules/passwd/apr1.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /*	$NetBSD: apr1.c,v 1.1.1.1 2014/05/28 09:58:28 tron Exp $	*/
2 
3 /* $OpenLDAP$ */
4 /*
5  * This file is derived from OpenLDAP Software. All of the modifications to
6  * OpenLDAP Software represented in the following file were developed by
7  * Devin J. Pohly <djpohly@gmail.com>. I have not assigned rights and/or
8  * interest in this work to any party.
9  *
10  * The extensions to OpenLDAP Software herein are subject to the following
11  * notice:
12  *
13  * Copyright 2011 Devin J. Pohly
14  * Portions Copyright 2011 Howard Chu
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted only as authorized by the OpenLDAP Public
17  * License.
18  *
19  * A portion of this code is used in accordance with the Beer-ware License,
20  * revision 42, as noted.
21  *
22  */
23 #include <lber.h>
24 #include <lber_pvt.h>
25 #include "lutil.h"
26 #include "lutil_md5.h"
27 #include <ac/string.h>
28 
29 #include <assert.h>
30 
31 /* the only difference between this and straight PHK is the magic */
32 static LUTIL_PASSWD_CHK_FUNC chk_apr1;
33 static LUTIL_PASSWD_HASH_FUNC hash_apr1;
34 static const struct berval scheme_apr1 = BER_BVC("{APR1}");
35 static const struct berval magic_apr1 = BER_BVC("$apr1$");
36 
37 static LUTIL_PASSWD_CHK_FUNC chk_bsdmd5;
38 static LUTIL_PASSWD_HASH_FUNC hash_bsdmd5;
39 static const struct berval scheme_bsdmd5 = BER_BVC("{BSDMD5}");
40 static const struct berval magic_bsdmd5 = BER_BVC("$1$");
41 
42 static const unsigned char apr64[] =
43 	"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
44 
45 #define APR_SALT_SIZE	8
46 
47 /* The algorithm implemented in this function was created by Poul-Henning
48  * Kamp and released under the following license:
49  * ----------------------------------------------------------------------------
50  * "THE BEER-WARE LICENSE" (Revision 42):
51  * <phk@FreeBSD.ORG> wrote this file. As long as you retain this notice you
52  * can do whatever you want with this stuff. If we meet some day, and you think
53  * this stuff is worth it, you can buy me a beer in return Poul-Henning Kamp
54  * ----------------------------------------------------------------------------
55  */
56 static void do_phk_hash(
57 	const struct berval *passwd,
58 	const struct berval *salt,
59 	const struct berval *magic,
60 	unsigned char *digest)
61 {
62 	lutil_MD5_CTX ctx, ctx1;
63 	int n;
64 
65 	/* Start hashing */
66 	lutil_MD5Init(&ctx);
67 	lutil_MD5Update(&ctx, (const unsigned char *) passwd->bv_val, passwd->bv_len);
68 	lutil_MD5Update(&ctx, (const unsigned char *) magic->bv_val, magic->bv_len);
69 	lutil_MD5Update(&ctx, (const unsigned char *) salt->bv_val, salt->bv_len);
70 	/* Inner hash */
71 	lutil_MD5Init(&ctx1);
72 	lutil_MD5Update(&ctx1, (const unsigned char *) passwd->bv_val, passwd->bv_len);
73 	lutil_MD5Update(&ctx1, (const unsigned char *) salt->bv_val, salt->bv_len);
74 	lutil_MD5Update(&ctx1, (const unsigned char *) passwd->bv_val, passwd->bv_len);
75 	lutil_MD5Final(digest, &ctx1);
76 	/* Nom start mixing things up */
77 	for (n = passwd->bv_len; n > 0; n -= LUTIL_MD5_BYTES)
78 		lutil_MD5Update(&ctx, digest,
79 				(n > LUTIL_MD5_BYTES ? LUTIL_MD5_BYTES : n));
80 	memset(digest, 0, LUTIL_MD5_BYTES);
81 	/* Curiouser and curiouser... */
82 	for (n = passwd->bv_len; n; n >>= 1)
83 		if (n & 1)
84 			lutil_MD5Update(&ctx, digest, 1);
85 		else
86 			lutil_MD5Update(&ctx, (const unsigned char *) passwd->bv_val, 1);
87 	lutil_MD5Final(digest, &ctx);
88 	/*
89 	 * Repeatedly hash things into the final value. This was originally
90 	 * intended to slow the algorithm down.
91 	 */
92 	for (n = 0; n < 1000; n++) {
93 		lutil_MD5Init(&ctx1);
94 		if (n & 1)
95 			lutil_MD5Update(&ctx1,
96 				(const unsigned char *) passwd->bv_val, passwd->bv_len);
97 		else
98 			lutil_MD5Update(&ctx1, digest, LUTIL_MD5_BYTES);
99 
100 		if (n % 3)
101 			lutil_MD5Update(&ctx1,
102 				(const unsigned char *) salt->bv_val, salt->bv_len);
103 		if (n % 7)
104 			lutil_MD5Update(&ctx1,
105 				(const unsigned char *) passwd->bv_val, passwd->bv_len);
106 
107 		if (n & 1)
108 			lutil_MD5Update(&ctx1, digest, LUTIL_MD5_BYTES);
109 		else
110 			lutil_MD5Update(&ctx1,
111 				(const unsigned char *) passwd->bv_val, passwd->bv_len);
112 		lutil_MD5Final(digest, &ctx1);
113 	}
114 }
115 
116 static int chk_phk(
117 	const struct berval *magic,
118 	const struct berval *passwd,
119 	const struct berval *cred,
120 	const char **text)
121 {
122 	unsigned char digest[LUTIL_MD5_BYTES];
123 	unsigned char *orig_pass;
124 	int rc, n;
125 	struct berval salt;
126 
127 	/* safety check */
128 	n = LUTIL_BASE64_DECODE_LEN(passwd->bv_len);
129 	if (n <= sizeof(digest))
130 		return LUTIL_PASSWD_ERR;
131 
132 	/* base64 un-encode password hash */
133 	orig_pass = (unsigned char *) ber_memalloc((size_t) (n + 1));
134 
135 	if (orig_pass == NULL)
136 		return LUTIL_PASSWD_ERR;
137 
138 	rc = lutil_b64_pton(passwd->bv_val, orig_pass, passwd->bv_len);
139 
140 	if (rc <= (int) sizeof(digest)) {
141 		ber_memfree(orig_pass);
142 		return LUTIL_PASSWD_ERR;
143 	}
144 
145 	salt.bv_val = (char *) &orig_pass[sizeof(digest)];
146 	salt.bv_len = rc - sizeof(digest);
147 
148 	do_phk_hash(cred, magic, &salt, digest);
149 
150 	if (text)
151 		*text = NULL;
152 
153 	/* compare */
154 	rc = memcmp((char *) orig_pass, (char *) digest, sizeof(digest));
155 	ber_memfree(orig_pass);
156 	return rc ?  LUTIL_PASSWD_ERR : LUTIL_PASSWD_OK;
157 }
158 
159 static int chk_apr1(
160 	const struct berval *scheme,
161 	const struct berval *passwd,
162 	const struct berval *cred,
163 	const char **text)
164 {
165 	return chk_phk(&magic_apr1, passwd, cred, text);
166 }
167 
168 static int chk_bsdmd5(
169 	const struct berval *scheme,
170 	const struct berval *passwd,
171 	const struct berval *cred,
172 	const char **text)
173 {
174 	return chk_phk(&magic_bsdmd5, passwd, cred, text);
175 }
176 
177 static int hash_phk(
178 	const struct berval *scheme,
179 	const struct berval *magic,
180 	const struct berval *passwd,
181 	struct berval *hash,
182 	const char **text)
183 {
184 	unsigned char digest_buf[LUTIL_MD5_BYTES];
185 	char salt_buf[APR_SALT_SIZE];
186 	struct berval digest;
187 	struct berval salt;
188 	int n;
189 
190 	digest.bv_val = (char *) digest_buf;
191 	digest.bv_len = sizeof(digest_buf);
192 	salt.bv_val = salt_buf;
193 	salt.bv_len = APR_SALT_SIZE;
194 
195 	/* generate random salt */
196 	if (lutil_entropy( (unsigned char *) salt.bv_val, salt.bv_len) < 0)
197 		return LUTIL_PASSWD_ERR;
198 	/* limit it to characters in the 64-char set */
199 	for (n = 0; n < salt.bv_len; n++)
200 		salt.bv_val[n] = apr64[salt.bv_val[n] % (sizeof(apr64) - 1)];
201 
202 	do_phk_hash(passwd, magic, &salt, digest_buf);
203 
204 	if (text)
205 		*text = NULL;
206 
207 	return lutil_passwd_string64(scheme, &digest, hash, &salt);
208 }
209 
210 static int hash_apr1(
211 	const struct berval *scheme,
212 	const struct berval *passwd,
213 	struct berval *hash,
214 	const char **text)
215 {
216 	return hash_phk(scheme, &magic_apr1, passwd, hash, text);
217 }
218 
219 static int hash_bsdmd5(
220 	const struct berval *scheme,
221 	const struct berval *passwd,
222 	struct berval *hash,
223 	const char **text)
224 {
225 	return hash_phk(scheme, &magic_bsdmd5, passwd, hash, text);
226 }
227 
228 int init_module(int argc, char *argv[]) {
229 	int rc;
230 	rc = lutil_passwd_add((struct berval *) &scheme_apr1, chk_apr1, hash_apr1);
231 	if ( !rc )
232 		rc = lutil_passwd_add((struct berval *) &scheme_bsdmd5,
233 			chk_bsdmd5, hash_bsdmd5);
234 	return rc;
235 }
236