4 * ----------------------------------------------------------------------------
5 * "THE BEER-WARE LICENSE" (Revision 42):
6 * <phk@login.dknet.dk> wrote this file. As long as you retain this notice you
7 * can do whatever you want with this stuff. If we meet some day, and you think
8 * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
9 * ----------------------------------------------------------------------------
11 * Origin: Id: crypt.c,v 1.3 1995/05/30 05:42:22 rgrimes Exp
18 static unsigned char itoa64[] = /* 0 ... 63 => ascii - 64 */
19 "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
21 static void to64(char *s, unsigned long v, int n)
24 *s++ = itoa64[v & 0x3f];
32 * Use MD5 for what it is best at...
35 char *MD5Name(crypt_md5)(const char *pw, const char *salt)
37 const char *magic = "$1$";
38 /* This string is magic for this algorithm. Having
39 * it this way, we can get get better later on */
40 static char passwd[120], *p;
41 static const char *sp, *ep;
42 unsigned char final[16];
47 /* Refine the Salt first */
50 /* If it starts with the magic string, then skip that */
51 if (!strncmp(sp, magic, strlen(magic)))
54 /* It stops at the first '$', max 8 chars */
55 for (ep = sp; *ep && *ep != '$' && ep < (sp + 8); ep++)
58 /* get the length of the true salt */
61 MD5Name(MD5Init)(&ctx);
63 /* The password first, since that is what is most unknown */
64 MD5Name(MD5Update)(&ctx,(unsigned const char *)pw,strlen(pw));
66 /* Then our magic string */
67 MD5Name(MD5Update)(&ctx,(unsigned const char *)magic,strlen(magic));
69 /* Then the raw salt */
70 MD5Name(MD5Update)(&ctx,(unsigned const char *)sp,sl);
72 /* Then just as many characters of the MD5(pw,salt,pw) */
73 MD5Name(MD5Init)(&ctx1);
74 MD5Name(MD5Update)(&ctx1,(unsigned const char *)pw,strlen(pw));
75 MD5Name(MD5Update)(&ctx1,(unsigned const char *)sp,sl);
76 MD5Name(MD5Update)(&ctx1,(unsigned const char *)pw,strlen(pw));
77 MD5Name(MD5Final)(final,&ctx1);
78 for (pl = strlen(pw); pl > 0; pl -= 16)
79 MD5Name(MD5Update)(&ctx,(unsigned const char *)final,pl>16 ? 16 : pl);
81 /* Don't leave anything around in vm they could use. */
82 memset(final, 0, sizeof final);
84 /* Then something really weird... */
85 for (j = 0, i = strlen(pw); i; i >>= 1)
87 MD5Name(MD5Update)(&ctx, (unsigned const char *)final+j, 1);
89 MD5Name(MD5Update)(&ctx, (unsigned const char *)pw+j, 1);
91 /* Now make the output string */
92 strcpy(passwd, magic);
93 strncat(passwd, sp, sl);
96 MD5Name(MD5Final)(final,&ctx);
99 * and now, just to make sure things don't run too fast
100 * On a 60 Mhz Pentium this takes 34 msec, so you would
101 * need 30 seconds to build a 1000 entry dictionary...
103 for (i = 0; i < 1000; i++) {
104 MD5Name(MD5Init)(&ctx1);
106 MD5Name(MD5Update)(&ctx1,(unsigned const char *)pw,strlen(pw));
108 MD5Name(MD5Update)(&ctx1,(unsigned const char *)final,16);
111 MD5Name(MD5Update)(&ctx1,(unsigned const char *)sp,sl);
114 MD5Name(MD5Update)(&ctx1,(unsigned const char *)pw,strlen(pw));
117 MD5Name(MD5Update)(&ctx1,(unsigned const char *)final,16);
119 MD5Name(MD5Update)(&ctx1,(unsigned const char *)pw,strlen(pw));
120 MD5Name(MD5Final)(final,&ctx1);
123 p = passwd + strlen(passwd);
125 l = (final[0] << 16) | (final[6] << 8) | final[12];
128 l = (final[1] << 16) | (final[7] << 8) | final[13];
131 l = (final[2] << 16) | (final[8] << 8) | final[14];
134 l = (final[3] << 16) | (final[9] << 8) | final[15];
137 l = (final[4] << 16) | (final[10] << 8) | final[5];
145 /* Don't leave anything around in vm they could use. */
146 memset(final, 0, sizeof final);