1 /*
2 * ----------------------------------------------------------------------------
3 * "THE BEER-WARE LICENSE" (Revision 42):
4 * <phk@login.dknet.dk> wrote this file. As long as you retain this
5 * notice you can do whatever you want with this stuff. If we meet some
6 * day, and you think this stuff is worth it, you can buy me a beer in
7 * return. Poul-Henning Kamp
8 * ----------------------------------------------------------------------------
9 */
10
11 #include "includes.h"
12
13 #if defined(HAVE_MD5_PASSWORDS) && !defined(HAVE_MD5_CRYPT)
14 #include <sys/types.h>
15
16 #include <string.h>
17
18 #include <openssl/md5.h>
19
20 /* 0 ... 63 => ascii - 64 */
21 static unsigned char itoa64[] =
22 "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
23
24 static char *magic = "$1$";
25
26 static char *
to64(unsigned long v,int n)27 to64(unsigned long v, int n)
28 {
29 static char buf[5];
30 char *s = buf;
31
32 if (n > 4)
33 return (NULL);
34
35 memset(buf, '\0', sizeof(buf));
36 while (--n >= 0) {
37 *s++ = itoa64[v&0x3f];
38 v >>= 6;
39 }
40
41 return (buf);
42 }
43
44 int
is_md5_salt(const char * salt)45 is_md5_salt(const char *salt)
46 {
47 return (strncmp(salt, magic, strlen(magic)) == 0);
48 }
49
50 char *
md5_crypt(const char * pw,const char * salt)51 md5_crypt(const char *pw, const char *salt)
52 {
53 static char passwd[120], salt_copy[9], *p;
54 static const char *sp, *ep;
55 unsigned char final[16];
56 int sl, pl, i, j;
57 MD5_CTX ctx, ctx1;
58 unsigned long l;
59
60 /* Refine the Salt first */
61 sp = salt;
62
63 /* If it starts with the magic string, then skip that */
64 if(strncmp(sp, magic, strlen(magic)) == 0)
65 sp += strlen(magic);
66
67 /* It stops at the first '$', max 8 chars */
68 for (ep = sp; *ep != '$'; ep++) {
69 if (*ep == '\0' || ep >= (sp + 8))
70 return (NULL);
71 }
72
73 /* get the length of the true salt */
74 sl = ep - sp;
75
76 /* Stash the salt */
77 memcpy(salt_copy, sp, sl);
78 salt_copy[sl] = '\0';
79
80 MD5_Init(&ctx);
81
82 /* The password first, since that is what is most unknown */
83 MD5_Update(&ctx, pw, strlen(pw));
84
85 /* Then our magic string */
86 MD5_Update(&ctx, magic, strlen(magic));
87
88 /* Then the raw salt */
89 MD5_Update(&ctx, sp, sl);
90
91 /* Then just as many characters of the MD5(pw, salt, pw) */
92 MD5_Init(&ctx1);
93 MD5_Update(&ctx1, pw, strlen(pw));
94 MD5_Update(&ctx1, sp, sl);
95 MD5_Update(&ctx1, pw, strlen(pw));
96 MD5_Final(final, &ctx1);
97
98 for(pl = strlen(pw); pl > 0; pl -= 16)
99 MD5_Update(&ctx, final, pl > 16 ? 16 : pl);
100
101 /* Don't leave anything around in vm they could use. */
102 memset(final, '\0', sizeof final);
103
104 /* Then something really weird... */
105 for (j = 0, i = strlen(pw); i != 0; i >>= 1)
106 if (i & 1)
107 MD5_Update(&ctx, final + j, 1);
108 else
109 MD5_Update(&ctx, pw + j, 1);
110
111 /* Now make the output string */
112 snprintf(passwd, sizeof(passwd), "%s%s$", magic, salt_copy);
113
114 MD5_Final(final, &ctx);
115
116 /*
117 * and now, just to make sure things don't run too fast
118 * On a 60 Mhz Pentium this takes 34 msec, so you would
119 * need 30 seconds to build a 1000 entry dictionary...
120 */
121 for(i = 0; i < 1000; i++) {
122 MD5_Init(&ctx1);
123 if (i & 1)
124 MD5_Update(&ctx1, pw, strlen(pw));
125 else
126 MD5_Update(&ctx1, final, 16);
127
128 if (i % 3)
129 MD5_Update(&ctx1, sp, sl);
130
131 if (i % 7)
132 MD5_Update(&ctx1, pw, strlen(pw));
133
134 if (i & 1)
135 MD5_Update(&ctx1, final, 16);
136 else
137 MD5_Update(&ctx1, pw, strlen(pw));
138
139 MD5_Final(final, &ctx1);
140 }
141
142 p = passwd + strlen(passwd);
143
144 l = (final[ 0]<<16) | (final[ 6]<<8) | final[12];
145 strlcat(passwd, to64(l, 4), sizeof(passwd));
146 l = (final[ 1]<<16) | (final[ 7]<<8) | final[13];
147 strlcat(passwd, to64(l, 4), sizeof(passwd));
148 l = (final[ 2]<<16) | (final[ 8]<<8) | final[14];
149 strlcat(passwd, to64(l, 4), sizeof(passwd));
150 l = (final[ 3]<<16) | (final[ 9]<<8) | final[15];
151 strlcat(passwd, to64(l, 4), sizeof(passwd));
152 l = (final[ 4]<<16) | (final[10]<<8) | final[ 5];
153 strlcat(passwd, to64(l, 4), sizeof(passwd));
154 l = final[11] ;
155 strlcat(passwd, to64(l, 2), sizeof(passwd));
156
157 /* Don't leave anything around in vm they could use. */
158 memset(final, 0, sizeof(final));
159 memset(salt_copy, 0, sizeof(salt_copy));
160 memset(&ctx, 0, sizeof(ctx));
161 memset(&ctx1, 0, sizeof(ctx1));
162 (void)to64(0, 4);
163
164 return (passwd);
165 }
166
167 #endif /* defined(HAVE_MD5_PASSWORDS) && !defined(HAVE_MD5_CRYPT) */
168