sfhashfcn.h

   1 /****************************************************************************
   2  *
   3  * Copyright (C) 2003-2009 Sourcefire, Inc.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License Version 2 as
   7  * published by the Free Software Foundation.  You may not use, modify or
   8  * distribute this program under any other version of the GNU General
   9  * Public License.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  *
  20  ****************************************************************************/
  21
  22 /*
  23         sfhashfcn.h
  24 */
  25 #ifndef SFHASHFCN_INCLUDE
  26 #define SFHASHFCN_INCLUDE
  27
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include <stdio.h>
  31 #include <time.h>
  32
  33 #define rot(x,k) (((x)<<(k)) | ((x)>>(32-(k))))
  34
  35 #define mix(a,b,c) \
  36 { \
  37   a -= c;  a ^= rot(c, 4);  c += b; \
  38   b -= a;  b ^= rot(a, 6);  a += c; \
  39   c -= b;  c ^= rot(b, 8);  b += a; \
  40   a -= c;  a ^= rot(c,16);  c += b; \
  41   b -= a;  b ^= rot(a,19);  a += c; \
  42   c -= b;  c ^= rot(b, 4);  b += a; \
  43 }
  44
  45 #define final(a,b,c) \
  46 { \
  47   c ^= b; c -= rot(b,14); \
  48   a ^= c; a -= rot(c,11); \
  49   b ^= a; b -= rot(a,25); \
  50   c ^= b; c -= rot(b,16); \
  51   a ^= c; a -= rot(c,4);  \
  52   b ^= a; b -= rot(a,14); \
  53   c ^= b; c -= rot(b,24); \
  54 }
  55
  56 typedef struct _SFHASHFCN {
  57
  58  unsigned seed;
  59  unsigned scale;
  60  unsigned hardener;
  61  unsigned (*hash_fcn)(struct _SFHASHFCN * p,
  62                       unsigned char *d,
  63                       int n );
  64  int      (*keycmp_fcn)( const void *s1,
  65                          const void *s2,
  66                          size_t n);
  67 } SFHASHFCN;
  68
  69 SFHASHFCN * sfhashfcn_new( int nrows );
  70 void sfhashfcn_free( SFHASHFCN * p );
  71 void sfhashfcn_static( SFHASHFCN * p );
  72
  73 unsigned sfhashfcn_hash( SFHASHFCN * p, unsigned char *d, int n );
  74
  75 int sfhashfcn_set_keyops( SFHASHFCN * p,
  76                           unsigned (*hash_fcn)( SFHASHFCN * p,
  77                                                 unsigned char *d,
  78                                                 int n),
  79                           int (*keycmp_fcn)( const void *s1,
  80                                              const void *s2,
  81                                              size_t n));
  82
  83
  84
  85 #endif