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   1 /* -*-c-*-
   2  *
   3  * $Id: ghash-def.h,v 1.5 2001/01/25 21:39:58 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 1.5  2001/01/25 21:39:58  mdw
  34  * Burn the hash context when it's done with, for paranoia's sake.
  35  *
  36  * Revision 1.4  2000/07/15 10:00:58  mdw
  37  * New generic hash operation for copying hash contexts.
  38  *
  39  * Revision 1.3  2000/07/02 18:27:42  mdw
  40  * (ghash->ops->done): Interface change.  Passing in a null buffer pointer
  41  * uses a buffer internal to the ghash object.  The operation returns the
  42  * address of the buffer it used.  Clients of generic hashes no longer need
  43  * to use dynamically allocated memory for hash results.
  44  *
  45  * Revision 1.2  2000/06/17 11:22:03  mdw
  46  * Use secure arena for memory allocation.  Minor changes in the generic
  47  * hash interface.
  48  *
  49  * Revision 1.1  1999/12/10 23:21:37  mdw
  50  * Generic interface.
  51  *
  52  */
  53
  54 #ifndef CATACOMB_GHASH_DEF_H
  55 #define CATACOMB_GHASH_DEF_H
  56
  57 #ifdef __cplusplus
  58   extern "C" {
  59 #endif
  60
  61 /*----- Header files ------------------------------------------------------*/
  62
  63 #include <mLib/bits.h>
  64 #include <mLib/sub.h>
  65
  66 #ifndef CATACOMB_ARENA_H
  67 #  include "arena.h"
  68 #endif
  69
  70 #ifndef CATACOMB_GHASH_H
  71 #  include "ghash.h"
  72 #endif
  73
  74 #ifndef CATACOMB_PARANOIA_H
  75 #  include "paranoia.h"
  76 #endif
  77
  78 /*----- Generic hash function interface -----------------------------------*/
  79
  80 /* --- @GHASH_DEF@ --- *
  81  *
  82  * Arguments:   @PRE, pre@ = prefixes for hash function
  83  *
  84  * Use:         Defines the generic hash instance.
  85  */
  86
  87 #define GHASH_DEF(PRE, pre)                                             \
  88                                                                         \
  89 static const ghash_ops gops;                                            \
  90                                                                         \
  91 typedef struct gctx {                                                   \
  92   ghash h;                                                              \
  93   pre##_ctx c;                                                          \
  94   octet buf[PRE##_HASHSZ];                                              \
  95 } gctx;                                                                 \
  96                                                                         \
  97 static ghash *ghinit(void)                                              \
  98 {                                                                       \
  99   gctx *g = S_CREATE(gctx);                                             \
 100   g->h.ops = &gops;                                                     \
 101   pre##_init(&g->c);                                                    \
 102   return (&g->h);                                                       \
 103 }                                                                       \
 104                                                                         \
 105 static void ghhash(ghash *h, const void *p, size_t sz)                  \
 106 {                                                                       \
 107   gctx *g = (gctx *)h;                                                  \
 108   pre##_hash(&g->c, p, sz);                                             \
 109 }                                                                       \
 110                                                                         \
 111 static octet *ghdone(ghash *h, void *buf)                               \
 112 {                                                                       \
 113   gctx *g = (gctx *)h;                                                  \
 114   if (!buf)                                                             \
 115     buf = g->buf;                                                       \
 116   pre##_done(&g->c, buf);                                               \
 117   return (buf);                                                         \
 118 }                                                                       \
 119                                                                         \
 120 static void ghdestroy(ghash *h)                                         \
 121 {                                                                       \
 122   gctx *g = (gctx *)h;                                                  \
 123   BURN(*g);                                                             \
 124   S_DESTROY(g);                                                         \
 125 }                                                                       \
 126                                                                         \
 127 static ghash *ghcopy(ghash *h)                                          \
 128 {                                                                       \
 129   gctx *g = (gctx *)h;                                                  \
 130   gctx *gg = S_CREATE(gctx);                                            \
 131   memcpy(gg, g, sizeof(gctx));                                          \
 132   return (&gg->h);                                                      \
 133 }                                                                       \
 134                                                                         \
 135 static const ghash_ops gops =                                           \
 136   { &pre, ghhash, ghdone, ghdestroy, ghcopy };                          \
 137 const gchash pre = { #pre, PRE##_HASHSZ, ghinit };
 138
 139 /*----- That's all, folks -------------------------------------------------*/
 140
 141 #ifdef __cplusplus
 142   }
 143 #endif
 144
 145 #endif