Mercurial > dovecot > core-2.2
view src/auth/password-scheme-md5crypt.c @ 20419:0dc214cf2e30
auth-policy: Add policy implementation
author | Aki Tuomi <aki.tuomi@dovecot.fi> |
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date | Fri, 03 Jun 2016 20:21:42 +0300 |
parents | 47add4b664af |
children |
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/* * ---------------------------------------------------------------------------- * "THE BEER-WARE LICENSE" (Revision 42): * <phk@login.dknet.dk> wrote this file. As long as you retain this notice you * can do whatever you want with this stuff. If we meet some day, and you think * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp * ---------------------------------------------------------------------------- */ /* * Ported from FreeBSD to Linux, only minimal changes. --marekm */ /* * Adapted from shadow-19990607 by Tudor Bosman, tudorb@jm.nu */ #include "lib.h" #include "safe-memset.h" #include "str.h" #include "md5.h" #include "password-scheme.h" static unsigned char itoa64[] = /* 0 ... 63 => ascii - 64 */ "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; static char magic[] = "$1$"; /* * This string is magic for * this algorithm. Having * it this way, we can get * get better later on */ static void to64(string_t *str, unsigned long v, int n) { while (--n >= 0) { str_append_c(str, itoa64[v&0x3f]); v >>= 6; } } /* * UNIX password * * Use MD5 for what it is best at... */ const char *password_generate_md5_crypt(const char *pw, const char *salt) { const char *sp,*ep; unsigned char final[MD5_RESULTLEN]; int sl,pl,i,j; struct md5_context ctx,ctx1; unsigned long l; string_t *passwd; size_t pw_len = strlen(pw); /* Refine the Salt first */ sp = salt; /* If it starts with the magic string, then skip that */ if (strncmp(sp, magic, sizeof(magic)-1) == 0) sp += sizeof(magic)-1; /* It stops at the first '$', max 8 chars */ for(ep=sp;*ep && *ep != '$' && ep < (sp+8);ep++) continue; /* get the length of the true salt */ sl = ep - sp; md5_init(&ctx); /* The password first, since that is what is most unknown */ md5_update(&ctx,pw,pw_len); /* Then our magic string */ md5_update(&ctx,magic,sizeof(magic)-1); /* Then the raw salt */ md5_update(&ctx,sp,sl); /* Then just as many characters of the MD5(pw,salt,pw) */ md5_init(&ctx1); md5_update(&ctx1,pw,pw_len); md5_update(&ctx1,sp,sl); md5_update(&ctx1,pw,pw_len); md5_final(&ctx1,final); for(pl = pw_len; pl > 0; pl -= MD5_RESULTLEN) md5_update(&ctx,final,pl>MD5_RESULTLEN ? MD5_RESULTLEN : pl); /* Don't leave anything around in vm they could use. */ safe_memset(final, 0, sizeof(final)); /* Then something really weird... */ for (j=0,i = pw_len; i ; i >>= 1) if(i&1) md5_update(&ctx, final+j, 1); else md5_update(&ctx, pw+j, 1); /* Now make the output string */ passwd = t_str_new(sl + 64); str_append(passwd, magic); str_append_n(passwd, sp, sl); str_append_c(passwd, '$'); md5_final(&ctx,final); /* * and now, just to make sure things don't run too fast * On a 60 Mhz Pentium this takes 34 msec, so you would * need 30 seconds to build a 1000 entry dictionary... */ for(i=0;i<1000;i++) { md5_init(&ctx1); if(i & 1) md5_update(&ctx1,pw,pw_len); else md5_update(&ctx1,final,MD5_RESULTLEN); if(i % 3) md5_update(&ctx1,sp,sl); if(i % 7) md5_update(&ctx1,pw,pw_len); if(i & 1) md5_update(&ctx1,final,MD5_RESULTLEN); else md5_update(&ctx1,pw,pw_len); md5_final(&ctx1,final); } l = (final[ 0]<<16) | (final[ 6]<<8) | final[12]; to64(passwd,l,4); l = (final[ 1]<<16) | (final[ 7]<<8) | final[13]; to64(passwd,l,4); l = (final[ 2]<<16) | (final[ 8]<<8) | final[14]; to64(passwd,l,4); l = (final[ 3]<<16) | (final[ 9]<<8) | final[15]; to64(passwd,l,4); l = (final[ 4]<<16) | (final[10]<<8) | final[ 5]; to64(passwd,l,4); l = final[11] ; to64(passwd,l,2); /* Don't leave anything around in vm they could use. */ safe_memset(final, 0, sizeof(final)); return str_c(passwd); }