1 /*
2 * Copyright (c) 2010
3 * The DragonFly Project. All rights reserved.
4 *
5 * This code is derived from software contributed to The DragonFly Project
6 * by Nolan Lum <nol888@gmail.com>
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the
17 * distribution.
18 * 3. Neither the name of The DragonFly Project nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific, prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
26 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
27 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
28 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
29 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
30 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
31 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
32 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 #include <sys/types.h>
37 #include <string.h>
38
39 #include "crypt.h"
40 #include "local.h"
41
42 /*
43 * New password crypt.
44 */
45
46 #define SHA256_SIZE 32
47
48 char*
crypt_deprecated_sha256(const char * pw,const char * salt)49 crypt_deprecated_sha256(const char *pw, const char *salt)
50 {
51 /*
52 * Magic constant (prefix) used to run over the password data.
53 *
54 * XXX:
55 *
56 * A bug below (sizeof instead of strlen) mandates the extra data after
57 * the closing $. This data is what just happened to be (consistently
58 * miraculously) on the stack following magic on 64-bit.
59 */
60 static const char *magic = "$3$\0sha5";
61
62 static char passwd[120], *p;
63 static const char *sp, *ep;
64 unsigned char final[SHA256_SIZE];
65 int sl;
66 struct sha256_ctx ctx;
67 unsigned long l;
68
69 /* Refine the salt. */
70 sp = salt;
71
72 /* If it starts with the magic string, then skip that. */
73 if (!strncmp(sp, magic, strlen(magic)))
74 sp += strlen(magic);
75
76 /* Stop at the first '$', max 8 chars. */
77 for (ep = sp; *ep && *ep != '$' && ep < (sp + 8); ep++)
78 continue;
79
80 /* Get the actual salt length. */
81 sl = ep - sp;
82
83 __crypt__sha256_init_ctx(&ctx);
84
85 /* Hash in the password first. */
86 __crypt__sha256_process_bytes(pw, strlen(pw), &ctx);
87
88 /*
89 * Then the magic string
90 *
91 * XXX: sizeof instead of strlen, must retain
92 */
93 __crypt__sha256_process_bytes(magic, sizeof(magic), &ctx);
94
95 /* Then the raw salt. */
96 __crypt__sha256_process_bytes(sp, sl, &ctx);
97
98 /* Finish and create the output string. */
99 __crypt__sha256_finish_ctx(&ctx, final);
100 strcpy(passwd, magic);
101 strncat(passwd, sp, sl);
102 strcat(passwd, "$");
103
104 p = passwd + strlen(passwd);
105
106 l = (final[ 0] << 16) | (final[11] << 8) | final[21];
107 _crypt_to64(p, l, 4); p += 4;
108 l = (final[ 1] << 16) | (final[12] << 8) | final[22];
109 _crypt_to64(p, l, 4); p += 4;
110 l = (final[ 2] << 16) | (final[13] << 8) | final[23];
111 _crypt_to64(p, l, 4); p += 4;
112 l = (final[ 3] << 16) | (final[14] << 8) | final[24];
113 _crypt_to64(p, l, 4); p += 4;
114 l = (final[ 4] << 16) | (final[15] << 8) | final[25];
115 _crypt_to64(p, l, 4); p += 4;
116 l = (final[ 5] << 16) | (final[16] << 8) | final[26];
117 _crypt_to64(p, l, 4); p += 4;
118 l = (final[ 6] << 16) | (final[17] << 8) | final[27];
119 _crypt_to64(p, l, 4); p += 4;
120 l = (final[ 7] << 16) | (final[18] << 8) | final[28];
121 _crypt_to64(p, l, 4); p += 4;
122 l = (final[ 8] << 16) | (final[19] << 8) | final[29];
123 _crypt_to64(p, l, 4); p += 4;
124 l = (final[ 9] << 16) | (final[20] << 8) | final[30];
125 _crypt_to64(p, l, 4); p += 4;
126 l = (final[10] << 16) | (final[31] << 8);
127 _crypt_to64(p, l, 4); p += 4;
128 *p = '\0';
129
130 /* Clear memory. */
131 memset(final, 0, sizeof(final));
132
133 return (passwd);
134 }
135