text: /*
   * ----------------------------------------------------------------------------
   * "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
   * ----------------------------------------------------------------------------
   *
   * $FreeBSD: src/lib/libcrypt/crypt-md5.c,v 1.5.2.1 2001/05/24 12:20:02 markm Exp $
   */
  
  #include <unistd.h>
  #include <stdio.h>
  #include <string.h>
  #include <err.h>
  
  #include "crypt.h"
  
  #define MD5Init		_libcrypt_MD5Init
  #define MD5Final	_libcrypt_MD5Final
  #define MD5Pad		_libcrypt_MD5Pad
  #define MD5Transform	_libcrypt_MD5Transform
  #define MD5Update	_libcrypt_MD5Update
  #define WITH_OPENSSL
  #include "private_md5.h"
  
  /* magic sizes, moved out from crypt.h */
  #define MD5_SIZE 16
  
  /*
   * UNIX password
   */
  
  char *
  crypt_md5(const char *pw, const char *salt)
  {
  	static const char *magic = "$1$";	/*
  					 * This string is magic for
  					 * this algorithm.  Having
  					 * it this way, we can get
  					 * get better later on
  					 */
  	static char     passwd[120], *p;
  	static const char *sp,*ep;
  	unsigned char	final[MD5_SIZE];
  	int sl,pl,i;
  	MD5_CTX	ctx,ctx1;
  	unsigned long l;
  
  	/* Refine the Salt first */
  	sp = salt;
  
  	/* If it starts with the magic string, then skip that */
  	if(!strncmp(sp,magic,strlen(magic)))
  		sp += strlen(magic);
  
  	/* 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;
  
  	MD5Init(&ctx);
  
  	/* The password first, since that is what is most unknown */
  	MD5Update(&ctx,pw,strlen(pw));
  
  	/* Then our magic string */
  	MD5Update(&ctx,magic,strlen(magic));
  
  	/* Then the raw salt */
  	MD5Update(&ctx,sp,sl);
  
  	/* Then just as many characters of the MD5(pw,salt,pw) */
  	MD5Init(&ctx1);
  	MD5Update(&ctx1,pw,strlen(pw));
  	MD5Update(&ctx1,sp,sl);
  	MD5Update(&ctx1,pw,strlen(pw));
  	MD5Final(final,&ctx1);
  	for(pl = strlen(pw); pl > 0; pl -= MD5_SIZE)
  		MD5Update(&ctx,final,pl>MD5_SIZE ? MD5_SIZE : pl);
  
  	/* Don't leave anything around in vm they could use. */
  	memset(final,0,sizeof final);
  
  	/* Then something really weird... */
  	for (i = strlen(pw); i ; i >>= 1)
  		if(i&1)
  		    MD5Update(&ctx, final, 1);
  		else
  		    MD5Update(&ctx, pw, 1);
  
  	/* Now make the output string */
  	strcpy(passwd,magic);
  	strncat(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,pw,strlen(pw));
  		else
  			MD5Update(&ctx1,final,MD5_SIZE);
  
  		if(i % 3)
  			MD5Update(&ctx1,sp,sl);
  
  		if(i % 7)
  			MD5Update(&ctx1,pw,strlen(pw));
  
  		if(i & 1)
  			MD5Update(&ctx1,final,MD5_SIZE);
  		else
  			MD5Update(&ctx1,pw,strlen(pw));
  		MD5Final(final,&ctx1);
  	}
  
  	p = passwd + strlen(passwd);
  
  	l = (final[ 0]<<16) | (final[ 6]<<8) | final[12];
  	_crypt_to64(p,l,4); p += 4;
  	l = (final[ 1]<<16) | (final[ 7]<<8) | final[13];
  	_crypt_to64(p,l,4); p += 4;
  	l = (final[ 2]<<16) | (final[ 8]<<8) | final[14];
  	_crypt_to64(p,l,4); p += 4;
  	l = (final[ 3]<<16) | (final[ 9]<<8) | final[15];
  	_crypt_to64(p,l,4); p += 4;
  	l = (final[ 4]<<16) | (final[10]<<8) | final[ 5];
  	_crypt_to64(p,l,4); p += 4;
  	l =                    final[11]                ;
  	_crypt_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;
  }
  
  