PC World Komputer 1998 July & August/Pcwk78a98.iso/Wtestowe/Clico/UNIX/SAMBA/SOURCE/SAMBA.TAR/samba-1.9.17/source/smbencrypt.c

C/C++ Source or Header | 1997-05-08 | 5KB | 197 lines

#ifdef SMB_PASSWD
/*
   Unix SMB/Netbios implementation.
   Version 1.9.
   SMB parameters and setup
   Copyright (C) Andrew Tridgell 1992-1997
   Modified by Jeremy Allison 1995.

   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 2 of the License, 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.
*/

#include "includes.h"
#include "des.h"
#include "md4.h"

extern int DEBUGLEVEL;

#include "byteorder.h"

void str_to_key(uchar *str,uchar *key)
{
  void des_set_odd_parity(des_cblock *);
  int i;

  key[0] = str[0]>>1;
  key[1] = ((str[0]&0x01)<<6) | (str[1]>>2);
  key[2] = ((str[1]&0x03)<<5) | (str[2]>>3);
  key[3] = ((str[2]&0x07)<<4) | (str[3]>>4);
  key[4] = ((str[3]&0x0F)<<3) | (str[4]>>5);
  key[5] = ((str[4]&0x1F)<<2) | (str[5]>>6);
  key[6] = ((str[5]&0x3F)<<1) | (str[6]>>7);
  key[7] = str[6]&0x7F;
  for (i=0;i<8;i++) {
    key[i] = (key[i]<<1);
  }
  des_set_odd_parity((des_cblock *)key);
}

void D1(uchar *k, uchar *d, uchar *out)
{
  des_key_schedule ks;
  des_cblock deskey;

  str_to_key(k,(uchar *)deskey);
#ifdef __FreeBSD__
  des_set_key(&deskey,ks);
#else /* __FreeBSD__ */
  des_set_key((des_cblock *)deskey,ks);
#endif /* __FreeBsd */
  des_ecb_encrypt((des_cblock *)d,(des_cblock *)out, ks, DES_DECRYPT);
}

void E1(uchar *k, uchar *d, uchar *out)
{
  des_key_schedule ks;
  des_cblock deskey;

  str_to_key(k,(uchar *)deskey);
#ifdef __FreeBSD__
  des_set_key(&deskey,ks);
#else /* __FreeBsd__ */
  des_set_key((des_cblock *)deskey,ks);
#endif /* __FreeBsd__ */
  des_ecb_encrypt((des_cblock *)d,(des_cblock *)out, ks, DES_ENCRYPT);
}

void E_P16(uchar *p14,uchar *p16)
{
  uchar sp7[7];
  /* the following constant makes us compatible with other
  implementations. Note that publishing this constant does not reduce the
  security of the encryption mechanism */
  uchar sp8[] = {0xAA,0xD3,0xB4,0x35,0xB5,0x14,0x4,0xEE};
  uchar x[8];

  memset(sp7,'\0',7);

  D1(sp7, sp8, x);
  E1(p14, x, p16);
  E1(p14+7, x, p16+8);
}

void E_P24(uchar *p21, uchar *c8, uchar *p24)
{
  E1(p21, c8, p24);
  E1(p21+7, c8, p24+8);
  E1(p21+14, c8, p24+16);
}


/*
   This implements the X/Open SMB password encryption
   It takes a password, a 8 byte "crypt key" and puts 24 bytes of
   encrypted password into p24 */
void SMBencrypt(uchar *passwd, uchar *c8, uchar *p24)
{
  uchar p14[15], p21[21];

  memset(p21,'\0',21);
  memset(p14,'\0',14);
  StrnCpy((char *)p14,(char *)passwd,14);

  strupper((char *)p14);
  E_P16(p14, p21);
  E_P24(p21, c8, p24);
}

/* Routines for Windows NT MD4 Hash functions. */
static int _my_wcslen(int16 *str)
{
    int len = 0;
    while(*str++ != 0)
        len++;
    return len;
}

/*
 * Convert a string into an NT UNICODE string.
 * Note that regardless of processor type
 * this must be in intel (little-endian)
 * format.
 */

static int _my_mbstowcs(int16 *dst, uchar *src, int len)
{
    int i;
    int16 val;

    for(i = 0; i < len; i++) {
        val = *src;
        SSVAL(dst,0,val);
        dst++;
        src++;
        if(val == 0)
            break;
    }
    return i;
}

/*
 * Creates the MD4 Hash of the users password in NT UNICODE.
 */

void E_md4hash(uchar *passwd, uchar *p16)
{
    int i, len;
    int16 wpwd[129];
    MDstruct MD;

    /* Password cannot be longer than 128 characters */
    len = strlen((char *)passwd);
    if(len > 128)
        len = 128;
    /* Password must be converted to NT unicode */
    _my_mbstowcs( wpwd, passwd, len);
    wpwd[len] = 0; /* Ensure string is null terminated */
    /* Calculate length in bytes */
    len = _my_wcslen(wpwd) * sizeof(int16);

    MDbegin(&MD);
    for(i = 0; i + 64 <= len; i += 64)
        MDupdate(&MD,wpwd + (i/2), 512);
    MDupdate(&MD,wpwd + (i/2),(len-i)*8);
    SIVAL(p16,0,MD.buffer[0]);
    SIVAL(p16,4,MD.buffer[1]);
    SIVAL(p16,8,MD.buffer[2]);
    SIVAL(p16,12,MD.buffer[3]);
}

/* Does the NT MD4 hash then des encryption. */

void SMBNTencrypt(uchar *passwd, uchar *c8, uchar *p24)
{
    uchar p21[21];

    memset(p21,'\0',21);

    E_md4hash(passwd, p21);
    E_P24(p21, c8, p24);
}

#else
 void smbencrypt_dummy(void){}
#endif