camellia-crypt-internal.c

   1 /* camellia-crypt-internal.c
   2  *
   3  * Copyright (C) 2006,2007
   4  * NTT (Nippon Telegraph and Telephone Corporation).
   5  *
   6  * Copyright (C) 2010 Niels Möller
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with this library; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  21  */
  22
  23 /*
  24  * Algorithm Specification
  25  *  http://info.isl.ntt.co.jp/crypt/eng/camellia/specifications.html
  26  */
  27
  28 /* Based on camellia.c ver 1.2.0, see
  29    http://info.isl.ntt.co.jp/crypt/eng/camellia/dl/camellia-LGPL-1.2.0.tar.gz.
  30  */
  31 #if HAVE_CONFIG_H
  32 # include "config.h"
  33 #endif
  34
  35 #include <assert.h>
  36
  37 #include "camellia-internal.h"
  38
  39 #include "macros.h"
  40
  41 #define CAMELLIA_FL(x, k) do {                  \
  42   uint32_t __xl, __xr, __kl, __kr, __t;         \
  43   __xl = (x) >> 32;                             \
  44   __xr = (x) & 0xffffffff;                      \
  45   __kl = (k) >> 32;                             \
  46   __kr = (k) & 0xffffffff;                      \
  47   __t = __xl & __kl;                            \
  48   __xr ^= ROL32(1, __t);                        \
  49   __xl ^= (__xr | __kr);                        \
  50   (x) = ((uint64_t) __xl << 32) | __xr;         \
  51 } while (0)
  52
  53 #define CAMELLIA_FLINV(x, k) do {               \
  54   uint32_t __xl, __xr, __kl, __kr, __t;         \
  55   __xl = (x) >> 32;                             \
  56   __xr = (x) & 0xffffffff;                      \
  57   __kl = (k) >> 32;                             \
  58   __kr = (k) & 0xffffffff;                      \
  59   __xl ^= (__xr | __kr);                        \
  60   __t = __xl & __kl;                            \
  61   __xr ^= ROL32(1, __t);                        \
  62   (x) = ((uint64_t) __xl << 32) | __xr;         \
  63 } while (0)
  64
  65 #define CAMELLIA_ROUNDSM(T, x, k, y) do {                       \
  66     uint32_t __il, __ir;                                        \
  67     __ir                                                        \
  68       = T->sp1110[(x) & 0xff]                           \
  69       ^ T->sp0222[((x) >> 24) & 0xff]                   \
  70       ^ T->sp3033[((x) >> 16) & 0xff]                   \
  71       ^ T->sp4404[((x) >> 8) & 0xff];                   \
  72     /* ir == (t6^t7^t8),(t5^t7^t8),(t5^t6^t8),(t5^t6^t7) */     \
  73     __il                                                        \
  74       = T->sp1110[ (x) >> 56]                           \
  75       ^ T->sp0222[((x) >> 48) & 0xff]                   \
  76       ^ T->sp3033[((x) >> 40) & 0xff]                   \
  77       ^ T->sp4404[((x) >> 32) & 0xff];                  \
  78     /* il == (t1^t3^t4),(t1^t2^t4),(t1^t2^t3),(t2^t3^t4) */     \
  79     __il ^= (k) >> 32;                                          \
  80     __ir ^= (k) & 0xffffffff;                                   \
  81     __ir ^= __il;                                               \
  82     /* ir == (t1^t3^t4^t6^t7^t8),(t1^t2^t4^t5^t7^t8),           \
  83              (t1^t2^t3^t5^t6^t8),(t2^t3^t4^t5^t6^t7)            \
  84           == y1,y2,y3,y4 */                                     \
  85     __il = ROL32(24, __il);                                     \
  86     /* il == (t2^t3^t4),(t1^t3^t4),(t1^t2^t4),(t1^t2^t3) */     \
  87     __il ^= __ir;                                               \
  88     /* il == (t1^t2^t6^t7^t8),(t2^t3^t5^t7^t8),                 \
  89              (t3^t4^t5^t6^t8),(t1^t4^t5^t6^t7)                  \
  90           == y5,y6,y7,y8 */                                     \
  91     y ^= ((uint64_t) __ir << 32) | __il;                        \
  92   } while (0)
  93
  94 void
  95 _camellia_crypt(const struct camellia_ctx *ctx,
  96                 const struct camellia_table *T,
  97                 unsigned length, uint8_t *dst,
  98                 const uint8_t *src)
  99 {
 100   FOR_BLOCKS(length, dst, src, CAMELLIA_BLOCK_SIZE)
 101     {
 102       uint64_t i0,i1;
 103       unsigned i;
 104
 105       i0 = READ_UINT64(src);
 106       i1 = READ_UINT64(src +  8);
 107
 108       /* pre whitening but absorb kw2*/
 109       i0 ^= ctx->keys[0];
 110
 111       /* main iteration */
 112
 113       CAMELLIA_ROUNDSM(T, i0,ctx->keys[1], i1);
 114       CAMELLIA_ROUNDSM(T, i1,ctx->keys[2], i0);
 115       CAMELLIA_ROUNDSM(T, i0,ctx->keys[3], i1);
 116       CAMELLIA_ROUNDSM(T, i1,ctx->keys[4], i0);
 117       CAMELLIA_ROUNDSM(T, i0,ctx->keys[5], i1);
 118       CAMELLIA_ROUNDSM(T, i1,ctx->keys[6], i0);
 119
 120       for (i = 0; i < ctx->nkeys - 8; i+= 8)
 121         {
 122           CAMELLIA_FL(i0, ctx->keys[i+7]);
 123           CAMELLIA_FLINV(i1, ctx->keys[i+8]);
 124
 125           CAMELLIA_ROUNDSM(T, i0,ctx->keys[i+9], i1);
 126           CAMELLIA_ROUNDSM(T, i1,ctx->keys[i+10], i0);
 127           CAMELLIA_ROUNDSM(T, i0,ctx->keys[i+11], i1);
 128           CAMELLIA_ROUNDSM(T, i1,ctx->keys[i+12], i0);
 129           CAMELLIA_ROUNDSM(T, i0,ctx->keys[i+13], i1);
 130           CAMELLIA_ROUNDSM(T, i1,ctx->keys[i+14], i0);
 131         }
 132
 133       /* post whitening but kw4 */
 134       i1 ^= ctx->keys[i+7];
 135
 136       WRITE_UINT64(dst     , i1);
 137       WRITE_UINT64(dst +  8, i0);
 138     }
 139 }