234 lines
6.9 KiB
C
234 lines
6.9 KiB
C
/*
|
|
* IRC - Internet Relay Chat, ircd/ircd_crypt_smd5.c
|
|
* Copyright (C) 2002 hikari
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 1, or (at your option)
|
|
* any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
*/
|
|
|
|
/**
|
|
* @file
|
|
* @brief Routines for Salted MD5 passwords
|
|
* @version $Id: ircd_crypt_smd5.c 1334 2005-03-20 16:06:30Z entrope $
|
|
*
|
|
* ircd_crypt_smd5 is largely taken from md5_crypt.c from the Linux PAM
|
|
* source code. it's been modified to fit in with ircu and some of the
|
|
* unneeded code has been removed. the source file md5_crypt.c has the
|
|
* following license, so if any of our opers or admins are in Denmark
|
|
* they better go buy them a drink ;) -- hikari
|
|
*
|
|
* ----------------------------------------------------------------------------
|
|
* "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
|
|
* ----------------------------------------------------------------------------
|
|
*
|
|
*/
|
|
#include "config.h"
|
|
#include "ircd_crypt.h"
|
|
#include "ircd_crypt_smd5.h"
|
|
#include "ircd_log.h"
|
|
#include "ircd_md5.h"
|
|
#include "s_debug.h"
|
|
#include "ircd_alloc.h"
|
|
|
|
/* #include <assert.h> -- Now using assert in ircd_log.h */
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
|
|
static unsigned char itoa64[] = /* 0 ... 63 => ascii - 64 */
|
|
"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
|
|
|
|
/** Converts a binary value into a BASE64 encoded string.
|
|
* @param s Pointer to the output string
|
|
* @param v The unsigned long we're working on
|
|
* @param n The number of bytes we're working with
|
|
*
|
|
* This is used to produce the normal MD5 hash everyone is familiar with.
|
|
* It takes the value v and converts n bytes of it it into an ASCII string in
|
|
* 6-bit chunks, the resulting string is put at the address pointed to by s.
|
|
*
|
|
*/
|
|
static void to64(char *s, unsigned long v, int n)
|
|
{
|
|
while (--n >= 0) {
|
|
*s++ = itoa64[v & 0x3f];
|
|
v >>= 6;
|
|
}
|
|
}
|
|
|
|
/** Produces a Salted MD5 crypt of a password using the supplied salt
|
|
* @param key The password we're encrypting
|
|
* @param salt The salt we're using to encrypt it
|
|
* @return The Salted MD5 password of key and salt
|
|
*
|
|
* Erm does exactly what the brief comment says. If you think I'm writing a
|
|
* description of how MD5 works, you have another think coming. Go and read
|
|
* Applied Cryptography by Bruce Schneier. The only difference is we use a
|
|
* salt at the beginning of the password to perturb it so that the same password
|
|
* doesn't always produce the same hash.
|
|
*
|
|
*/
|
|
const char* ircd_crypt_smd5(const char* key, const char* salt)
|
|
{
|
|
const char *magic = "$1$";
|
|
static char passwd[120];
|
|
char *p;
|
|
const char *sp, *ep;
|
|
unsigned char final[16];
|
|
int sl, pl, i, j;
|
|
MD5_CTX ctx, ctx1;
|
|
unsigned long l;
|
|
|
|
assert(NULL != key);
|
|
assert(NULL != salt);
|
|
|
|
Debug((DEBUG_DEBUG, "ircd_crypt_smd5: key = %s", key));
|
|
Debug((DEBUG_DEBUG, "ircd_crypt_smd5: salt = %s", salt));
|
|
|
|
/* Refine the Salt first */
|
|
ep = sp = salt;
|
|
|
|
for (ep = sp; *ep && *ep != '$' && ep < (sp + 8); ep++)
|
|
continue;
|
|
|
|
/* get the length of the true salt */
|
|
sl = ep - sp;
|
|
|
|
MD5Init(&ctx);
|
|
|
|
/* The password first, since that is what is most unknown */
|
|
MD5Update(&ctx,(unsigned const char *)key,strlen(key));
|
|
|
|
/* Then our magic string */
|
|
MD5Update(&ctx,(unsigned const char *)magic,strlen(magic));
|
|
|
|
/* Then the raw salt */
|
|
MD5Update(&ctx,(unsigned const char *)sp,sl);
|
|
|
|
/* Then just as many characters of the MD5(key,salt,key) */
|
|
MD5Init(&ctx1);
|
|
MD5Update(&ctx1,(unsigned const char *)key,strlen(key));
|
|
MD5Update(&ctx1,(unsigned const char *)sp,sl);
|
|
MD5Update(&ctx1,(unsigned const char *)key,strlen(key));
|
|
MD5Final(final,&ctx1);
|
|
for (pl = strlen(key); pl > 0; pl -= 16)
|
|
MD5Update(&ctx,(unsigned const char *)final,pl>16 ? 16 : pl);
|
|
|
|
/* Don't leave anything around in vm they could use. */
|
|
memset(final, 0, sizeof final);
|
|
|
|
/* Then something really weird... */
|
|
for (j = 0, i = strlen(key); i; i >>= 1)
|
|
if (i & 1)
|
|
MD5Update(&ctx, (unsigned const char *)final+j, 1);
|
|
else
|
|
MD5Update(&ctx, (unsigned const char *)key+j, 1);
|
|
|
|
/* Now make the output string. */
|
|
memset(passwd, 0, 120);
|
|
strncpy(passwd, sp, sl);
|
|
strcat(passwd, "$");
|
|
|
|
MD5Final(final,&ctx);
|
|
|
|
/*
|
|
* 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++) {
|
|
MD5Init(&ctx1);
|
|
|
|
if (i & 1)
|
|
MD5Update(&ctx1,(unsigned const char *)key,strlen(key));
|
|
else
|
|
MD5Update(&ctx1,(unsigned const char *)final,16);
|
|
|
|
if (i % 3)
|
|
MD5Update(&ctx1,(unsigned const char *)sp,sl);
|
|
|
|
if (i % 7)
|
|
MD5Update(&ctx1,(unsigned const char *)key,strlen(key));
|
|
|
|
if (i & 1)
|
|
MD5Update(&ctx1,(unsigned const char *)final,16);
|
|
else
|
|
MD5Update(&ctx1,(unsigned const char *)key,strlen(key));
|
|
|
|
MD5Final(final,&ctx1);
|
|
}
|
|
|
|
p = passwd + strlen(passwd);
|
|
|
|
Debug((DEBUG_DEBUG, "passwd = %s", passwd));
|
|
|
|
/* Turn the encrypted binary data into a BASE64 encoded string we can read
|
|
* and display -- hikari */
|
|
l = (final[0] << 16) | (final[6] << 8) | final[12];
|
|
to64(p, l, 4);
|
|
p += 4;
|
|
l = (final[1] << 16) | (final[7] << 8) | final[13];
|
|
to64(p, l, 4);
|
|
p += 4;
|
|
l = (final[2] << 16) | (final[8] << 8) | final[14];
|
|
to64(p, l, 4);
|
|
p += 4;
|
|
l = (final[3] << 16) | (final[9] << 8) | final[15];
|
|
to64(p, l, 4);
|
|
p += 4;
|
|
l = (final[4] << 16) | (final[10] << 8) | final[5];
|
|
to64(p, l, 4);
|
|
p += 4;
|
|
l = final[11];
|
|
to64(p, l, 2);
|
|
p += 2;
|
|
*p = '\0';
|
|
|
|
/* Don't leave anything around in vm they could use. */
|
|
memset(final, 0, sizeof final);
|
|
|
|
return passwd;
|
|
}
|
|
|
|
/* end borrowed code */
|
|
|
|
/** Register ourself with the list of crypt mechanisms
|
|
* Registers the SMD5 mechanism in the list of available crypt mechanisms. When
|
|
* we're modular this will be the entry function for the module.
|
|
*
|
|
*/
|
|
void ircd_register_crypt_smd5(void)
|
|
{
|
|
crypt_mech_t* crypt_mech;
|
|
|
|
if ((crypt_mech = (crypt_mech_t*)MyMalloc(sizeof(crypt_mech_t))) == NULL)
|
|
{
|
|
Debug((DEBUG_MALLOC, "Could not allocate space for crypt_smd5"));
|
|
return;
|
|
}
|
|
|
|
crypt_mech->mechname = "smd5";
|
|
crypt_mech->shortname = "crypt_smd5";
|
|
crypt_mech->description = "Salted MD5 password hash mechanism.";
|
|
crypt_mech->crypt_function = &ircd_crypt_smd5;
|
|
crypt_mech->crypt_token = "$SMD5$";
|
|
crypt_mech->crypt_token_size = 6 ;
|
|
|
|
ircd_crypt_register_mech(crypt_mech);
|
|
|
|
return;
|
|
}
|