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
19 static unsigned char itoa64[] = /* 0 ... 63 => ascii - 64 */
20 "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
22 static void to64(char *s, unsigned long v, int n)
25 *s++ = itoa64[v & 0x3f];
33 * Use MD5 for what it is best at...
36 char *MD5Name(crypt_md5)(const char *pw, const char *salt)
38 const char *magic = "$1$";
39 /* This string is magic for this algorithm. Having
40 * it this way, we can get get better later on */
43 unsigned char final[16];
48 /* Refine the Salt first */
51 /* TODO: now that we're using malloc'ed memory, get rid of the
52 strange constant buffer size. */
55 /* If it starts with the magic string, then skip that */
56 if (!strncmp(sp, magic, strlen(magic)))
59 /* It stops at the first '$', max 8 chars */
60 for (ep = sp; *ep && *ep != '$' && ep < (sp + 8); ep++)
63 /* get the length of the true salt */
66 MD5Name(MD5Init)(&ctx);
68 /* The password first, since that is what is most unknown */
69 MD5Name(MD5Update)(&ctx,(unsigned const char *)pw,strlen(pw));
71 /* Then our magic string */
72 MD5Name(MD5Update)(&ctx,(unsigned const char *)magic,strlen(magic));
74 /* Then the raw salt */
75 MD5Name(MD5Update)(&ctx,(unsigned const char *)sp,sl);
77 /* Then just as many characters of the MD5(pw,salt,pw) */
78 MD5Name(MD5Init)(&ctx1);
79 MD5Name(MD5Update)(&ctx1,(unsigned const char *)pw,strlen(pw));
80 MD5Name(MD5Update)(&ctx1,(unsigned const char *)sp,sl);
81 MD5Name(MD5Update)(&ctx1,(unsigned const char *)pw,strlen(pw));
82 MD5Name(MD5Final)(final,&ctx1);
83 for (pl = strlen(pw); pl > 0; pl -= 16)
84 MD5Name(MD5Update)(&ctx,(unsigned const char *)final,pl>16 ? 16 : pl);
86 /* Don't leave anything around in vm they could use. */
87 memset(final, 0, sizeof final);
89 /* Then something really weird... */
90 for (j = 0, i = strlen(pw); i; i >>= 1)
92 MD5Name(MD5Update)(&ctx, (unsigned const char *)final+j, 1);
94 MD5Name(MD5Update)(&ctx, (unsigned const char *)pw+j, 1);
96 /* Now make the output string */
97 strcpy(passwd, magic);
98 strncat(passwd, sp, sl);
101 MD5Name(MD5Final)(final,&ctx);
104 * and now, just to make sure things don't run too fast
105 * On a 60 Mhz Pentium this takes 34 msec, so you would
106 * need 30 seconds to build a 1000 entry dictionary...
108 for (i = 0; i < 1000; i++) {
109 MD5Name(MD5Init)(&ctx1);
111 MD5Name(MD5Update)(&ctx1,(unsigned const char *)pw,strlen(pw));
113 MD5Name(MD5Update)(&ctx1,(unsigned const char *)final,16);
116 MD5Name(MD5Update)(&ctx1,(unsigned const char *)sp,sl);
119 MD5Name(MD5Update)(&ctx1,(unsigned const char *)pw,strlen(pw));
122 MD5Name(MD5Update)(&ctx1,(unsigned const char *)final,16);
124 MD5Name(MD5Update)(&ctx1,(unsigned const char *)pw,strlen(pw));
125 MD5Name(MD5Final)(final,&ctx1);
128 p = passwd + strlen(passwd);
130 l = (final[0] << 16) | (final[6] << 8) | final[12];
133 l = (final[1] << 16) | (final[7] << 8) | final[13];
136 l = (final[2] << 16) | (final[8] << 8) | final[14];
139 l = (final[3] << 16) | (final[9] << 8) | final[15];
142 l = (final[4] << 16) | (final[10] << 8) | final[5];
150 /* Don't leave anything around in vm they could use. */
151 memset(final, 0, sizeof final);