2 * ----------------------------------------------------------------------------
3 * "THE BEER-WARE LICENSE" (Revision 42):
4 * <phk@login.dknet.dk> wrote this file. As long as you retain this notice you
5 * can do whatever you want with this stuff. If we meet some day, and you think
6 * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
7 * ----------------------------------------------------------------------------
9 * $FreeBSD: src/lib/libcrypt/crypt-md5.c,v 1.5.2.1 2001/05/24 12:20:02 markm Exp $
10 * $DragonFly: src/lib/libcrypt/crypt-md5.c,v 1.3 2005/08/04 17:27:09 drhodus Exp $
25 crypt_md5(const char *pw, const char *salt)
27 static char *magic = "$1$"; /*
28 * This string is magic for
29 * this algorithm. Having
30 * it this way, we can get
33 static char passwd[120], *p;
34 static const char *sp,*ep;
35 unsigned char final[MD5_SIZE];
40 /* Refine the Salt first */
43 /* If it starts with the magic string, then skip that */
44 if(!strncmp(sp,magic,strlen(magic)))
47 /* It stops at the first '$', max 8 chars */
48 for(ep=sp;*ep && *ep != '$' && ep < (sp+8);ep++)
51 /* get the length of the true salt */
56 /* The password first, since that is what is most unknown */
57 MD5Update(&ctx,pw,strlen(pw));
59 /* Then our magic string */
60 MD5Update(&ctx,magic,strlen(magic));
62 /* Then the raw salt */
63 MD5Update(&ctx,sp,sl);
65 /* Then just as many characters of the MD5(pw,salt,pw) */
67 MD5Update(&ctx1,pw,strlen(pw));
68 MD5Update(&ctx1,sp,sl);
69 MD5Update(&ctx1,pw,strlen(pw));
70 MD5Final(final,&ctx1);
71 for(pl = strlen(pw); pl > 0; pl -= MD5_SIZE)
72 MD5Update(&ctx,final,pl>MD5_SIZE ? MD5_SIZE : pl);
74 /* Don't leave anything around in vm they could use. */
75 memset(final,0,sizeof final);
77 /* Then something really weird... */
78 for (i = strlen(pw); i ; i >>= 1)
80 MD5Update(&ctx, final, 1);
82 MD5Update(&ctx, pw, 1);
84 /* Now make the output string */
86 strncat(passwd,sp,sl);
92 * and now, just to make sure things don't run too fast
93 * On a 60 Mhz Pentium this takes 34 msec, so you would
94 * need 30 seconds to build a 1000 entry dictionary...
99 MD5Update(&ctx1,pw,strlen(pw));
101 MD5Update(&ctx1,final,MD5_SIZE);
104 MD5Update(&ctx1,sp,sl);
107 MD5Update(&ctx1,pw,strlen(pw));
110 MD5Update(&ctx1,final,MD5_SIZE);
112 MD5Update(&ctx1,pw,strlen(pw));
113 MD5Final(final,&ctx1);
116 p = passwd + strlen(passwd);
118 l = (final[ 0]<<16) | (final[ 6]<<8) | final[12];
119 _crypt_to64(p,l,4); p += 4;
120 l = (final[ 1]<<16) | (final[ 7]<<8) | final[13];
121 _crypt_to64(p,l,4); p += 4;
122 l = (final[ 2]<<16) | (final[ 8]<<8) | final[14];
123 _crypt_to64(p,l,4); p += 4;
124 l = (final[ 3]<<16) | (final[ 9]<<8) | final[15];
125 _crypt_to64(p,l,4); p += 4;
126 l = (final[ 4]<<16) | (final[10]<<8) | final[ 5];
127 _crypt_to64(p,l,4); p += 4;
129 _crypt_to64(p,l,2); p += 2;
132 /* Don't leave anything around in vm they could use. */
133 memset(final,0,sizeof final);