chiark - git - mdw - catacomb/blob - ghash-def.h

   1 /* -*-c-*-
   2  *
   3  * $Id: ghash-def.h,v 1.4 2000/07/15 10:00:58 mdw Exp $
   4  *
   5  * Definitions for generic hash interface
   6  *
   7  * (c) 1999 Straylight/Edgeware
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of Catacomb.
  13  *
  14  * Catacomb is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU Library General Public License as
  16  * published by the Free Software Foundation; either version 2 of the
  17  * License, or (at your option) any later version.
  18  *
  19  * Catacomb is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU Library General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU Library General Public
  25  * License along with Catacomb; if not, write to the Free
  26  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  27  * MA 02111-1307, USA.
  28  */
  29
  30 /*----- Revision history --------------------------------------------------*
  31  *
  32  * $Log: ghash-def.h,v $
  33  * Revision 1.4  2000/07/15 10:00:58  mdw
  34  * New generic hash operation for copying hash contexts.
  35  *
  36  * Revision 1.3  2000/07/02 18:27:42  mdw
  37  * (ghash->ops->done): Interface change.  Passing in a null buffer pointer
  38  * uses a buffer internal to the ghash object.  The operation returns the
  39  * address of the buffer it used.  Clients of generic hashes no longer need
  40  * to use dynamically allocated memory for hash results.
  41  *
  42  * Revision 1.2  2000/06/17 11:22:03  mdw
  43  * Use secure arena for memory allocation.  Minor changes in the generic
  44  * hash interface.
  45  *
  46  * Revision 1.1  1999/12/10 23:21:37  mdw
  47  * Generic interface.
  48  *
  49  */
  50
  51 #ifndef CATACOMB_GHASH_DEF_H
  52 #define CATACOMB_GHASH_DEF_H
  53
  54 #ifdef __cplusplus
  55   extern "C" {
  56 #endif
  57
  58 /*----- Header files ------------------------------------------------------*/
  59
  60 #include <mLib/bits.h>
  61 #include <mLib/sub.h>
  62
  63 #ifndef CATACOMB_ARENA_H
  64 #  include "arena.h"
  65 #endif
  66
  67 #ifndef CATACOMB_GHASH_H
  68 #  include "ghash.h"
  69 #endif
  70
  71 /*----- Generic hash function interface -----------------------------------*/
  72
  73 /* --- @GHASH_DEF@ --- *
  74  *
  75  * Arguments:   @PRE, pre@ = prefixes for hash function
  76  *
  77  * Use:         Defines the generic hash instance.
  78  */
  79
  80 #define GHASH_DEF(PRE, pre)                                             \
  81                                                                         \
  82 static const ghash_ops gops;                                            \
  83                                                                         \
  84 typedef struct gctx {                                                   \
  85   ghash h;                                                              \
  86   pre##_ctx c;                                                          \
  87   octet buf[PRE##_HASHSZ];                                              \
  88 } gctx;                                                                 \
  89                                                                         \
  90 static ghash *ghinit(void)                                              \
  91 {                                                                       \
  92   gctx *g = S_CREATE(gctx);                                             \
  93   g->h.ops = &gops;                                                     \
  94   pre##_init(&g->c);                                                    \
  95   return (&g->h);                                                       \
  96 }                                                                       \
  97                                                                         \
  98 static void ghhash(ghash *h, const void *p, size_t sz)                  \
  99 {                                                                       \
 100   gctx *g = (gctx *)h;                                                  \
 101   pre##_hash(&g->c, p, sz);                                             \
 102 }                                                                       \
 103                                                                         \
 104 static octet *ghdone(ghash *h, void *buf)                               \
 105 {                                                                       \
 106   gctx *g = (gctx *)h;                                                  \
 107   if (!buf)                                                             \
 108     buf = g->buf;                                                       \
 109   pre##_done(&g->c, buf);                                               \
 110   return (buf);                                                         \
 111 }                                                                       \
 112                                                                         \
 113 static void ghdestroy(ghash *h)                                         \
 114 {                                                                       \
 115   gctx *g = (gctx *)h;                                                  \
 116   S_DESTROY(g);                                                         \
 117 }                                                                       \
 118                                                                         \
 119 static ghash *ghcopy(ghash *h)                                          \
 120 {                                                                       \
 121   gctx *g = (gctx *)h;                                                  \
 122   gctx *gg = S_CREATE(gctx);                                            \
 123   memcpy(gg, g, sizeof(gctx));                                          \
 124   return (&gg->h);                                                      \
 125 }                                                                       \
 126                                                                         \
 127 static const ghash_ops gops =                                           \
 128   { &pre, ghhash, ghdone, ghdestroy, ghcopy };                          \
 129 const gchash pre = { #pre, PRE##_HASHSZ, ghinit };
 130
 131 /*----- That's all, folks -------------------------------------------------*/
 132
 133 #ifdef __cplusplus
 134   }
 135 #endif
 136
 137 #endif