/* crypto/des/fcrypt.c */
/* Copyright (C) 1995-1997 Eric Young (eay@mincom.oz.au)
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young (eay@mincom.oz.au).
 * The implementation was written so as to conform with Netscapes SSL.
 * 
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson (tjh@mincom.oz.au).
 * 
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young (eay@mincom.oz.au)"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from 
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson (tjh@mincom.oz.au)"
 * 
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * 
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */

#include <stdio.h>

/* Eric Young.
 * This version of crypt has been developed from my MIT compatable
 * DES library.
 * The library is available at pub/Crypto/DES at ftp.psy.uq.oz.au
 * eay@mincom.oz.au or eay@psych.psy.uq.oz.au
 */

/* Modification by Jens Kupferschmidt (Cu)
 * I have included directive PARA for shared memory computers.
 * I have included a directive LONGCRYPT to using this routine to cipher
 * passwords with more then 8 bytes like HP-UX 10.x it used. The MAXPLEN
 * definition is the maximum of lenght of password and can changed. I have
 * defined 24.
 */

#define FCRYPT_MOD(R,u,t,E0,E1,tmp) \
	u=R>>16; \
	t=R^u; \
	u=t&E0; t=t&E1; \
	tmp=(u<<16); u^=R^s[S  ]; u^=tmp; \
	tmp=(t<<16); t^=R^s[S+1]; t^=tmp

#define DES_FCRYPT
#include "des_locl.h"
#undef DES_FCRYPT

#undef PERM_OP
#define PERM_OP(a,b,t,n,m) ((t)=((((a)>>(n))^(b))&(m)),\
	(b)^=(t),\
	(a)^=((t)<<(n)))

#undef HPERM_OP
#define HPERM_OP(a,t,n,m) ((t)=((((a)<<(16-(n)))^(a))&(m)),\
	(a)=(a)^(t)^(t>>(16-(n))))\

#ifdef PARA
#define STATIC
#else
#define STATIC	static
#endif

/* It is really only FreeBSD that still suffers from MD5 based crypts */
#ifdef __FreeBSD__
#define MD5_CRYPT_SUPPORT 1
#endif
#if     MD5_CRYPT_SUPPORT
/*
 * ----------------------------------------------------------------------------
 * "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
 * ----------------------------------------------------------------------------
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <md5.h>

static unsigned char itoa64[] =		/* 0 ... 63 => ascii - 64 */
	"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";

static void
to64(s, v, n)
	char *s;
	unsigned long v;
	int n;
{
	while (--n >= 0) {
		*s++ = itoa64[v&0x3f];
		v >>= 6;
	}
}

/*
 * UNIX password
 *
 * Use MD5 for what it is best at...
 */

static
char *
crypt_md5(pw, salt)
	register const char *pw;
	register const char *salt;
{
	static 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[16];
	int sl,pl,i,j;
	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 -= 16)
		MD5Update(&ctx,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(pw); i ; i >>= 1)
		if(i&1)
		    MD5Update(&ctx, final+j, 1);
		else
		    MD5Update(&ctx, pw+j, 1);

	/* Now make the output string */
	snprintf (passwd, sizeof(passwd),
		  "%s%.*s$", magic, sl, sp);

	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,16);

		if(i % 3)
			MD5Update(&ctx1,sp,sl);

		if(i % 7)
			MD5Update(&ctx1,pw,strlen(pw));

		if(i & 1)
			MD5Update(&ctx1,final,16);
		else
			MD5Update(&ctx1,pw,strlen(pw));
		MD5Final(final,&ctx1);
	}

	p = passwd + strlen(passwd);

	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;
}
#endif /* MD5_CRYPT_SUPPORT */

#ifndef NOPROTO

STATIC int fcrypt_body(DES_LONG *out0, DES_LONG *out1,
	des_key_schedule ks, DES_LONG Eswap0, DES_LONG Eswap1);

#else

STATIC int fcrypt_body();

#endif

/* Added more values to handle illegal salt values the way normal
 * crypt() implementations do.  The patch was sent by 
 * Bjorn Gronvall <bg@sics.se>
 */
static unsigned const char con_salt[128]={
0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,
0xDA,0xDB,0xDC,0xDD,0xDE,0xDF,0xE0,0xE1,
0xE2,0xE3,0xE4,0xE5,0xE6,0xE7,0xE8,0xE9,
0xEA,0xEB,0xEC,0xED,0xEE,0xEF,0xF0,0xF1,
0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,
0xFA,0xFB,0xFC,0xFD,0xFE,0xFF,0x00,0x01,
0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,
0x0A,0x0B,0x05,0x06,0x07,0x08,0x09,0x0A,
0x0B,0x0C,0x0D,0x0E,0x0F,0x10,0x11,0x12,
0x13,0x14,0x15,0x16,0x17,0x18,0x19,0x1A,
0x1B,0x1C,0x1D,0x1E,0x1F,0x20,0x21,0x22,
0x23,0x24,0x25,0x20,0x21,0x22,0x23,0x24,
0x25,0x26,0x27,0x28,0x29,0x2A,0x2B,0x2C,
0x2D,0x2E,0x2F,0x30,0x31,0x32,0x33,0x34,
0x35,0x36,0x37,0x38,0x39,0x3A,0x3B,0x3C,
0x3D,0x3E,0x3F,0x40,0x41,0x42,0x43,0x44,
};

static unsigned const char cov_2char[64]={
0x2E,0x2F,0x30,0x31,0x32,0x33,0x34,0x35,
0x36,0x37,0x38,0x39,0x41,0x42,0x43,0x44,
0x45,0x46,0x47,0x48,0x49,0x4A,0x4B,0x4C,
0x4D,0x4E,0x4F,0x50,0x51,0x52,0x53,0x54,
0x55,0x56,0x57,0x58,0x59,0x5A,0x61,0x62,
0x63,0x64,0x65,0x66,0x67,0x68,0x69,0x6A,
0x6B,0x6C,0x6D,0x6E,0x6F,0x70,0x71,0x72,
0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7A
};

#ifndef NOPROTO
#ifdef PERL5
char *des_crypt(const char *buf,const char *salt);
#else
char *crypt(const char *buf,const char *salt);
#endif
#else
#ifdef PERL5
char *des_crypt();
#else
char *crypt();
#endif
#endif

#ifdef PERL5
char *des_crypt(buf,salt)
#else
char *crypt(buf,salt)
#endif
const char *buf;
const char *salt;
	{
	static char buff[14];

#if     MD5_CRYPT_SUPPORT
	if (!strncmp(salt, "$1$", 3))
		return crypt_md5(buf, salt);
#endif

	return(des_fcrypt(buf,salt,buff));
	}


char *des_fcrypt(buf,salt,ret)
const char *buf;
const char *salt;
char *ret;
	{
	unsigned int i,j,x,y;
	DES_LONG Eswap0,Eswap1;
	DES_LONG out[2],ll;
	des_cblock key;
	des_key_schedule ks;
	unsigned char bb[9];
	unsigned char *b=bb;
	unsigned char c,u;

	/* eay 25/08/92
	 * If you call crypt("pwd","*") as often happens when you
	 * have * as the pwd field in /etc/passwd, the function
	 * returns *\0XXXXXXXXX
	 * The \0 makes the string look like * so the pwd "*" would
	 * crypt to "*".  This was found when replacing the crypt in
	 * our shared libraries.  People found that the disbled
	 * accounts effectivly had no passwd :-(. */
	x=ret[0]=((salt[0] == '\0')?'A':salt[0]);
	Eswap0=con_salt[x]<<2;
	x=ret[1]=((salt[1] == '\0')?'A':salt[1]);
	Eswap1=con_salt[x]<<6;

/* EAY
r=strlen(buf);
r=(r+7)/8;
*/
	for (i=0; i<8; i++)
		{
		c= *(buf++);
		if (!c) break;
		key[i]=(c<<1);
		}
	for (; i<8; i++)
		key[i]=0;

	des_set_key((des_cblock *)(key),ks);
	fcrypt_body(&(out[0]),&(out[1]),ks,Eswap0,Eswap1);

	ll=out[0]; l2c(ll,b);
	ll=out[1]; l2c(ll,b);
	y=0;
	u=0x80;
	bb[8]=0;
	for (i=2; i<13; i++)
		{
		c=0;
		for (j=0; j<6; j++)
			{
			c<<=1;
			if (bb[y] & u) c|=1;
			u>>=1;
			if (!u)
				{
				y++;
				u=0x80;
				}
			}
		ret[i]=cov_2char[c];
		}
	ret[13]='\0';
	return(ret);
	}

STATIC int fcrypt_body(out0, out1, ks, Eswap0, Eswap1)
DES_LONG *out0;
DES_LONG *out1;
des_key_schedule ks;
DES_LONG Eswap0;
DES_LONG Eswap1;
	{
	register DES_LONG l,r,t,u;
#ifdef DES_PTR
	register unsigned char *des_SP=(unsigned char *)des_SPtrans;
#endif
	register DES_LONG *s;
	register int j;
	register DES_LONG E0,E1;

	l=0;
	r=0;

	s=(DES_LONG *)ks;
	E0=Eswap0;
	E1=Eswap1;

	for (j=0; j<25; j++)
		{
#ifdef DES_UNROLL
		register int i;

		for (i=0; i<32; i+=8)
			{
			D_ENCRYPT(l,r,i+0); /*  1 */
			D_ENCRYPT(r,l,i+2); /*  2 */
			D_ENCRYPT(l,r,i+4); /*  3 */
			D_ENCRYPT(r,l,i+6); /*  4 */
			}
#else
		D_ENCRYPT(l,r, 0); /*  1 */
		D_ENCRYPT(r,l, 2); /*  2 */
		D_ENCRYPT(l,r, 4); /*  3 */
		D_ENCRYPT(r,l, 6); /*  4 */
		D_ENCRYPT(l,r, 8); /*  5 */
		D_ENCRYPT(r,l,10); /*  6 */
		D_ENCRYPT(l,r,12); /*  7 */
		D_ENCRYPT(r,l,14); /*  8 */
		D_ENCRYPT(l,r,16); /*  9 */
		D_ENCRYPT(r,l,18); /*  10 */
		D_ENCRYPT(l,r,20); /*  11 */
		D_ENCRYPT(r,l,22); /*  12 */
		D_ENCRYPT(l,r,24); /*  13 */
		D_ENCRYPT(r,l,26); /*  14 */
		D_ENCRYPT(l,r,28); /*  15 */
		D_ENCRYPT(r,l,30); /*  16 */
#endif
		t=l;
		l=r;
		r=t;
		}
	l=ROTATE(l,3)&0xffffffffL;
	r=ROTATE(r,3)&0xffffffffL;

	PERM_OP(l,r,t, 1,0x55555555L);
	PERM_OP(r,l,t, 8,0x00ff00ffL);
	PERM_OP(l,r,t, 2,0x33333333L);
	PERM_OP(r,l,t,16,0x0000ffffL);
	PERM_OP(l,r,t, 4,0x0f0f0f0fL);

	*out0=r;
	*out1=l;
	return(0);
	}