helpers/basic_auth/NCSA/crypt_md5.cc

   1 /*
   2  * Shamelessly stolen from linux-pam, and adopted to work with
   3  * OpenSSL md5 implementation and any magic string
   4  *
   5  * Origin2: md5_crypt.c,v 1.1.1.1 2000/01/03 17:34:46 gafton Exp
   6  *
   7  * ----------------------------------------------------------------------------
   8  * "THE BEER-WARE LICENSE" (Revision 42):
   9  * <phk@login.dknet.dk> wrote this file.  As long as you retain this notice you
  10  * can do whatever you want with this stuff. If we meet some day, and you think
  11  * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
  12  * ----------------------------------------------------------------------------
  13  *
  14  * Origin: Id: crypt.c,v 1.3 1995/05/30 05:42:22 rgrimes Exp
  15  *
  16  */
  17 #include "squid.h"
  18
  19 #if HAVE_STRING_H
  20 #include <string.h>
  21 #endif
  22 #if HAVE_STDIO_H
  23 #include <stdio.h>
  24 #endif
  25
  26 #include "crypt_md5.h"
  27 #include "md5.h"
  28
  29 static unsigned char itoa64[] = /* 0 ... 63 => ascii - 64 */
  30     "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
  31
  32 static void md5to64(char *s, unsigned long v, int n)
  33 {
  34     while (--n >= 0) {
  35         *s = itoa64[v & 0x3f];
  36         ++s;
  37         v >>= 6;
  38     }
  39 }
  40
  41 /*
  42  * MD5 hash a password
  43  *
  44  * Use MD5 for what it is best at...
  45  *
  46  * If salt begins with $ then it is assumed to be on the form
  47  *   $magic$salt$...
  48  * If not the normal UNIX magic $1$ is used.
  49  */
  50
  51 char *crypt_md5(const char *pw, const char *salt)
  52 {
  53     const char *magic = "$1$";
  54     int magiclen = 3;
  55     static char passwd[120], *p;
  56     static const char *sp, *ep;
  57     unsigned char final[16];
  58     int sl, pl, i, j;
  59     SquidMD5_CTX ctx, ctx1;
  60     unsigned long l;
  61
  62     if (*salt == '$') {
  63         magic = salt;
  64         ++salt;
  65         while (*salt && *salt != '$')
  66             ++salt;
  67         if (*salt == '$') {
  68             ++salt;
  69             magiclen = salt - magic;
  70         } else {
  71             salt = magic;
  72             magic = "$1$";
  73         }
  74     }
  75
  76     /* Refine the Salt first */
  77     sp = salt;
  78
  79     /* It stops at the first '$', max 8 chars */
  80     for (ep = sp; *ep && *ep != '$' && ep < (sp + 8); ++ep)
  81         continue;
  82
  83     /* get the length of the true salt */
  84     sl = ep - sp;
  85
  86     SquidMD5Init(&ctx);
  87
  88     /* The password first, since that is what is most unknown */
  89     SquidMD5Update(&ctx, (unsigned const char *) pw, strlen(pw));
  90
  91     /* Then our magic string */
  92     SquidMD5Update(&ctx, (unsigned const char *) magic, magiclen);
  93
  94     /* Then the raw salt */
  95     SquidMD5Update(&ctx, (unsigned const char *) sp, sl);
  96
  97     /* Then just as many characters of the MD5(pw,salt,pw) */
  98     SquidMD5Init(&ctx1);
  99     SquidMD5Update(&ctx1, (unsigned const char *) pw, strlen(pw));
 100     SquidMD5Update(&ctx1, (unsigned const char *) sp, sl);
 101     SquidMD5Update(&ctx1, (unsigned const char *) pw, strlen(pw));
 102     SquidMD5Final(final, &ctx1);
 103     for (pl = strlen(pw); pl > 0; pl -= 16)
 104         SquidMD5Update(&ctx, (unsigned const char *) final, pl > 16 ? 16 : pl);
 105
 106     /* Don't leave anything around in vm they could use. */
 107     memset(final, 0, sizeof final);
 108
 109     /* Then something really weird... */
 110     for (j = 0, i = strlen(pw); i; i >>= 1)
 111         if (i & 1)
 112             SquidMD5Update(&ctx, (unsigned const char *) final + j, 1);
 113         else
 114             SquidMD5Update(&ctx, (unsigned const char *) pw + j, 1);
 115
 116     /* Now make the output string */
 117     memset(passwd, 0, sizeof(passwd));
 118     strncat(passwd, magic, magiclen);
 119     strncat(passwd, sp, sl);
 120     strcat(passwd, "$");
 121
 122     SquidMD5Final(final, &ctx);
 123
 124     /*
 125      * and now, just to make sure things don't run too fast
 126      * On a 60 Mhz Pentium this takes 34 msec, so you would
 127      * need 30 seconds to build a 1000 entry dictionary...
 128      */
 129     for (i = 0; i < 1000; ++i) {
 130         SquidMD5Init(&ctx1);
 131         if (i & 1)
 132             SquidMD5Update(&ctx1, (unsigned const char *) pw, strlen(pw));
 133         else
 134             SquidMD5Update(&ctx1, (unsigned const char *) final, 16);
 135
 136         if (i % 3)
 137             SquidMD5Update(&ctx1, (unsigned const char *) sp, sl);
 138
 139         if (i % 7)
 140             SquidMD5Update(&ctx1, (unsigned const char *) pw, strlen(pw));
 141
 142         if (i & 1)
 143             SquidMD5Update(&ctx1, (unsigned const char *) final, 16);
 144         else
 145             SquidMD5Update(&ctx1, (unsigned const char *) pw, strlen(pw));
 146         SquidMD5Final(final, &ctx1);
 147     }
 148
 149     p = passwd + strlen(passwd);
 150
 151     l = (final[0] << 16) | (final[6] << 8) | final[12];
 152     md5to64(p, l, 4);
 153     p += 4;
 154     l = (final[1] << 16) | (final[7] << 8) | final[13];
 155     md5to64(p, l, 4);
 156     p += 4;
 157     l = (final[2] << 16) | (final[8] << 8) | final[14];
 158     md5to64(p, l, 4);
 159     p += 4;
 160     l = (final[3] << 16) | (final[9] << 8) | final[15];
 161     md5to64(p, l, 4);
 162     p += 4;
 163     l = (final[4] << 16) | (final[10] << 8) | final[5];
 164     md5to64(p, l, 4);
 165     p += 4;
 166     l = final[11];
 167     md5to64(p, l, 2);
 168     p += 2;
 169     *p = '\0';
 170
 171     /* Don't leave anything around in vm they could use. */
 172     memset(final, 0, sizeof final);
 173
 174     return passwd;
 175 }
 176
 177 /* Created by Ramon de Carvalho <ramondecarvalho@yahoo.com.br>
 178    Refined by Rodrigo Rubira Branco <rodrigo@kernelhacking.com>
 179 */
 180 char *md5sum(const char *s)
 181 {
 182     static unsigned char digest[16];
 183     SquidMD5_CTX ctx;
 184     int idx;
 185     static char sum[33];
 186
 187     memset(digest,0,16);
 188
 189     SquidMD5Init(&ctx);
 190     SquidMD5Update(&ctx,(const unsigned char *)s,strlen(s));
 191     SquidMD5Final(digest,&ctx);
 192
 193     for (idx=0; idx<16; ++idx)
 194         snprintf(&sum[idx*2],(33-(idx*2)),"%02x",digest[idx]);
 195
 196     sum[32]='\0';
 197
 198     /* Don't leave anything around in vm they could use. */
 199     memset(digest, 0, sizeof digest);
 200
 201     return sum;
 202 }
 203