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   1 /* -*-c-*-
   2  *
   3  * $Id: hmac-def.h,v 1.1 1999/12/10 23:16:40 mdw Exp $
   4  *
   5  * Definitions for HMAC and NMAC
   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: hmac-def.h,v $
  33  * Revision 1.1  1999/12/10 23:16:40  mdw
  34  * Split mode macros into interface and implementation.
  35  *
  36  */
  37
  38 #ifndef CATACOMB_HMAC_DEF_H
  39 #define CATACOMB_HMAC_DEF_H
  40
  41 #ifdef __cplusplus
  42   extern "C" {
  43 #endif
  44
  45 /*----- Header files ------------------------------------------------------*/
  46
  47 #include <stdlib.h>
  48 #include <string.h>
  49
  50 #include <mLib/bits.h>
  51 #include <mLib/sub.h>
  52
  53 #ifndef CATACOMB_GMAC_H
  54 #  include "gmac.h"
  55 #endif
  56
  57 #ifndef CATACOMB_PARANOIA_H
  58 #  include "paranoia.h"
  59 #endif
  60
  61 /*----- Macros ------------------------------------------------------------*/
  62
  63 /* --- @HMAC_DEF@ --- *
  64  *
  65  * Arguments:   @PRE@, @pre@ = prefixes for the underlying hash function
  66  *
  67  * Use:         Creates implementations for the HMAC and NMAC functions.
  68  */
  69
  70 #define HMAC_DEF(PRE, pre)                                              \
  71                                                                         \
  72 /* --- @pre_nmacinit@ --- *                                             \
  73  *                                                                      \
  74  * Arguments:   @pre_macctx *key@ = pointer to a MAC key object         \
  75  *              @const void *ok@ = pointer to outer hash init vector    \
  76  *              @const void *ik@ = pointer to inner hash init vector    \
  77  *                                                                      \
  78  * Returns:     ---                                                     \
  79  *                                                                      \
  80  * Use:         Initializes a MAC key for doing NMAC hashing.           \
  81  */                                                                     \
  82                                                                         \
  83 void pre##_nmacinit(pre##_mackey *key, const void *ok, const void *ik)  \
  84 {                                                                       \
  85   memcpy(key->ochain, ok, PRE##_HASHSZ);                                \
  86   memcpy(key->ichain, ik, PRE##_HASHSZ);                                \
  87   key->ocount = key->icount = 0;                                        \
  88 }                                                                       \
  89                                                                         \
  90 /* --- @pre_hmacinit@ --- *                                             \
  91  *                                                                      \
  92  * Arguments:   @pre_mackey *key@ = pointer to MAC key object           \
  93  *              @const void *k@ = pointer to key to use                 \
  94  *              @size_t sz@ = size of key data                          \
  95  *                                                                      \
  96  * Returns:     ---                                                     \
  97  *                                                                      \
  98  * Use:         Initializes a MAC key for doing HMAC hashing.  Keys     \
  99  *              longer than the hash function's output size aren't very \
 100  *              useful, but are accepted.  Keys longer than the hash's  \
 101  *              block size are also accepted; they are hashed before    \
 102  *              use, as specified in RFC2104.                           \
 103  */                                                                     \
 104                                                                         \
 105 void pre##_hmacinit(pre##_mackey *key, const void *k, size_t sz)        \
 106 {                                                                       \
 107   int i;                                                                \
 108   const octet *kbuf = k;                                                \
 109   pre##_ctx ctx;                                                        \
 110   octet buf[PRE##_HASHSZ];                                              \
 111                                                                         \
 112   if (sz > PRE##_BUFSZ) {                                               \
 113     pre##_init(&ctx);                                                   \
 114     pre##_hash(&ctx, k, sz);                                            \
 115     pre##_done(&ctx, buf);                                              \
 116     kbuf = buf;                                                         \
 117     sz = PRE##_HASHSZ;                                                  \
 118   }                                                                     \
 119                                                                         \
 120   pre##_init(&ctx);                                                     \
 121   memset(ctx.buf, 0x5c, PRE##_BUFSZ);                                   \
 122   for (i = 0; i < sz; i++)                                              \
 123     ctx.buf[i] ^= kbuf[i];                                              \
 124   pre##_compress(&ctx, ctx.buf);                                        \
 125   pre##_state(&ctx, key->ochain);                                       \
 126                                                                         \
 127   pre##_init(&ctx);                                                     \
 128   memset(ctx.buf, 0x36, PRE##_BUFSZ);                                   \
 129   for (i = 0; i < sz; i++)                                              \
 130     ctx.buf[i] ^= kbuf[i];                                              \
 131   pre##_compress(&ctx, ctx.buf);                                        \
 132   pre##_state(&ctx, key->ichain);                                       \
 133                                                                         \
 134   key->ocount = key->icount = PRE##_BUFSZ;                              \
 135   BURN(ctx);                                                            \
 136 }                                                                       \
 137                                                                         \
 138 /* --- @pre_macinit@ --- *                                              \
 139  *                                                                      \
 140  * Arguments:   @pre_macctx *ctx@ = pointer to MAC context block        \
 141  *              @const pre_mackey *key@ = pointer to MAC key block      \
 142  *                                                                      \
 143  * Returns:     ---                                                     \
 144  *                                                                      \
 145  * Use:         Instantiates a MAC context from a key block.            \
 146  */                                                                     \
 147                                                                         \
 148 void pre##_macinit(pre##_macctx *ctx, const pre##_mackey *key)          \
 149 {                                                                       \
 150   memcpy(ctx->chain, key->ochain, PRE##_HASHSZ);                        \
 151   ctx->count = key->ocount;                                             \
 152   pre##_set(&ctx->ctx, key->ichain, key->icount);                       \
 153 }                                                                       \
 154                                                                         \
 155 /* --- @pre_machash@ --- *                                              \
 156  *                                                                      \
 157  * Arguments:   @pre_macctx *ctx@ = pointer to MAC context block        \
 158  *              @const void *buf@ = pointer to buffer                   \
 159  *              @size_t sz@ = size of the buffer                        \
 160  *                                                                      \
 161  * Returns:     ---                                                     \
 162  *                                                                      \
 163  * Use:         Hashes a buffer.                                        \
 164  */                                                                     \
 165                                                                         \
 166 void pre##_machash(pre##_macctx *ctx, const void *buf, size_t sz)       \
 167 {                                                                       \
 168   pre##_hash(&ctx->ctx, buf, sz);                                       \
 169 }                                                                       \
 170                                                                         \
 171 /* --- @pre_macdone@ --- *                                              \
 172  *                                                                      \
 173  * Arguments:   @pre_macctx *ctx@ = pointer to MAC context block        \
 174  *              @void *mac@ = pointer to buffer to receive MAC          \
 175  *                                                                      \
 176  * Returns:     ---                                                     \
 177  *                                                                      \
 178  * Use:         Returns the result of a MAC computation.                \
 179  */                                                                     \
 180                                                                         \
 181 void pre##_macdone(pre##_macctx *ctx, void *mac)                        \
 182 {                                                                       \
 183   pre##_done(&ctx->ctx, mac);                                           \
 184   pre##_set(&ctx->ctx, ctx->chain, ctx->count);                         \
 185   pre##_hash(&ctx->ctx, mac, PRE##_HASHSZ);                             \
 186   pre##_done(&ctx->ctx, mac);                                           \
 187 }                                                                       \
 188                                                                         \
 189 /* --- Generic MAC interface --- */                                     \
 190                                                                         \
 191 static const gmac_ops gkops;                                            \
 192 static const ghash_ops gops;                                            \
 193                                                                         \
 194 typedef struct gkctx {                                                  \
 195   gmac m;                                                               \
 196   pre##_mackey k;                                                       \
 197 } gkctx;                                                                \
 198                                                                         \
 199 typedef struct gctx {                                                   \
 200   ghash h;                                                              \
 201   pre##_macctx c;                                                       \
 202 } gctx;                                                                 \
 203                                                                         \
 204 static ghash *gkinit(gmac *m)                                           \
 205 {                                                                       \
 206   gkctx *gk = (gkctx *)m;                                               \
 207   gctx *g = CREATE(gctx);                                               \
 208   g->h.ops = &gops;                                                     \
 209   pre##_macinit(&g->c, &gk->k);                                         \
 210   return (&g->h);                                                       \
 211 }                                                                       \
 212                                                                         \
 213 static gmac *gkey(const void *k, size_t sz)                             \
 214 {                                                                       \
 215   gkctx *gk = CREATE(gkctx);                                            \
 216   gk->m.ops = &gkops;                                                   \
 217   pre##_hmacinit(&gk->k, k, sz);                                        \
 218   return (&gk->m);                                                      \
 219 }                                                                       \
 220                                                                         \
 221 static void ghhash(ghash *h, const void *p, size_t sz)                  \
 222 {                                                                       \
 223   gctx *g = (gctx *)h;                                                  \
 224   pre##_machash(&g->c, p, sz);                                          \
 225 }                                                                       \
 226                                                                         \
 227 static void ghdone(ghash *h, void *buf)                                 \
 228 {                                                                       \
 229   gctx *g = (gctx *)h;                                                  \
 230   pre##_macdone(&g->c, buf);                                            \
 231 }                                                                       \
 232                                                                         \
 233 static void ghdestroy(ghash *h)                                         \
 234 {                                                                       \
 235   gctx *g = (gctx *)h;                                                  \
 236   DESTROY(g);                                                           \
 237 }                                                                       \
 238                                                                         \
 239 static void gkdestroy(gmac *m)                                          \
 240 {                                                                       \
 241   gkctx *gk = (gkctx *)m;                                               \
 242   DESTROY(gk);                                                          \
 243 }                                                                       \
 244                                                                         \
 245 const gcmac pre##_hmac = { { #pre "-hmac", PRE##_HASHSZ }, gkey };      \
 246 static const gmac_ops gkops = { &pre##_hmac.b, gkinit, gkdestroy };     \
 247 static const ghash_ops gops =                                           \
 248   { &pre##_hmac.b, ghhash, ghdone, ghdestroy };                         \
 249                                                                         \
 250 HMAC_TEST(PRE, pre)
 251
 252 /* --- @HMAC_TEST@ --- *
 253  *
 254  * Arguments:   @PRE@, @pre@ = prefixes for hash-specfic definitions
 255  *
 256  * Use:         Standard test rig for MAC functions.
 257  */
 258
 259 #ifdef TEST_RIG
 260
 261 #include <stdio.h>
 262
 263 #include <mLib/dstr.h>
 264 #include <mLib/quis.h>
 265 #include <mLib/testrig.h>
 266
 267 #define HMAC_TEST(PRE, pre)                                             \
 268                                                                         \
 269 static int macverify(dstr *v)                                           \
 270 {                                                                       \
 271   pre##_macctx cctx;                                                    \
 272   pre##_mackey ckey;                                                    \
 273   int ok = 1;                                                           \
 274   int i;                                                                \
 275   octet *p;                                                             \
 276   int szs[] = { 1, 7, 192, -1, 0 }, *ip;                                \
 277   size_t csz;                                                           \
 278   dstr d;                                                               \
 279                                                                         \
 280   dstr_create(&d);                                                      \
 281   dstr_ensure(&d, PRE##_HASHSZ);                                        \
 282   d.len = PRE##_HASHSZ;                                                 \
 283                                                                         \
 284   pre##_hmacinit(&ckey, v[1].buf, v[1].len);                            \
 285                                                                         \
 286   for (ip = szs; *ip; ip++) {                                           \
 287     i = *ip;                                                            \
 288     csz = v[0].len;                                                     \
 289     if (i == -1)                                                        \
 290       i = csz;                                                          \
 291     if (i > csz)                                                        \
 292       continue;                                                         \
 293     p = (octet *)v[0].buf;                                              \
 294     pre##_macinit(&cctx, &ckey);                                        \
 295     while (csz) {                                                       \
 296       if (i > csz)                                                      \
 297         i = csz;                                                        \
 298       pre##_machash(&cctx, p, i);                                       \
 299       p += i;                                                           \
 300       csz -= i;                                                         \
 301     }                                                                   \
 302     pre##_macdone(&cctx, d.buf);                                        \
 303     if (memcmp(d.buf, v[2].buf, PRE##_HASHSZ) != 0) {                   \
 304       printf("\nfail:\n\tstep = %i\n\tinput = `%s'\n\tkey = ",          \
 305              *ip, v[0].buf);                                            \
 306       type_hex.dump(&v[1], stdout);                                     \
 307       fputs("\n\texpected = ", stdout);                                 \
 308       type_hex.dump(&v[2], stdout);                                     \
 309       fputs("\n\tcomputed = ", stdout);                                 \
 310       type_hex.dump(&d, stdout);                                        \
 311       putchar('\n');                                                    \
 312       ok = 0;                                                           \
 313     }                                                                   \
 314   }                                                                     \
 315                                                                         \
 316   dstr_destroy(&d);                                                     \
 317   return (ok);                                                          \
 318 }                                                                       \
 319                                                                         \
 320 static test_chunk macdefs[] = {                                         \
 321   { #pre "-hmac", macverify,                                            \
 322     { &type_string, &type_hex, &type_hex, 0 } },                        \
 323   { 0, 0, { 0 } }                                                       \
 324 };                                                                      \
 325                                                                         \
 326 int main(int argc, char *argv[])                                        \
 327 {                                                                       \
 328   ego(argv[0]);                                                         \
 329   test_run(argc, argv, macdefs, SRCDIR"/tests/" #pre);                  \
 330   return (0);                                                           \
 331 }
 332
 333 #else
 334 #  define HMAC_TEST(PRE, pre)
 335 #endif
 336
 337 /*----- That's all, folks -------------------------------------------------*/
 338
 339 #ifdef __cplusplus
 340   }
 341 #endif
 342
 343 #endif