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camellia-set-encrypt-key.c
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* camellia-set-encrypt-key.c (camellia_set_encrypt_key): Reintroduce CAMELLIA_F_HALF_INV, for 32-bit machines. * camellia-crypt-internal.c (CAMELLIA_ROUNDSM): Two variants, differing in where addition of the key is done. * x86/camellia-crypt-internal.asm: Moved addition of key. Rev: nettle/ChangeLog:1.110 Rev: nettle/camellia-crypt-internal.c:1.4 Rev: nettle/camellia-set-encrypt-key.c:1.6
camellia-set-encrypt-key.c 9.19 KiB
/* camellia-set-encrypt-key.c
*
* Key setup for the camellia block cipher.
*/
/*
* Copyright (C) 2006,2007
* NTT (Nippon Telegraph and Telephone Corporation).
*
* Copyright (C) 2010 Niels Mller
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/*
* Algorithm Specification
* http://info.isl.ntt.co.jp/crypt/eng/camellia/specifications.html
*/
/* Based on camellia.c ver 1.2.0, see
http://info.isl.ntt.co.jp/crypt/eng/camellia/dl/camellia-LGPL-1.2.0.tar.gz.
*/
#if HAVE_CONFIG_H
# include "config.h"
#endif
#include <assert.h>
#include <limits.h>
#include "camellia-internal.h"
#include "macros.h"
/* key constants */
#define SIGMA1 0xA09E667F3BCC908BULL
#define SIGMA2 0xB67AE8584CAA73B2ULL
#define SIGMA3 0xC6EF372FE94F82BEULL
#define SIGMA4 0x54FF53A5F1D36F1CULL
#define SIGMA5 0x10E527FADE682D1DULL
#define SIGMA6 0xB05688C2B3E6C1FDULL
#define CAMELLIA_SP1110(INDEX) (_nettle_camellia_table.sp1110[(int)(INDEX)])
#define CAMELLIA_SP0222(INDEX) (_nettle_camellia_table.sp0222[(int)(INDEX)])
#define CAMELLIA_SP3033(INDEX) (_nettle_camellia_table.sp3033[(int)(INDEX)])
#define CAMELLIA_SP4404(INDEX) (_nettle_camellia_table.sp4404[(int)(INDEX)])
#define CAMELLIA_F(x, k, y) do { \
uint32_t __yl, __yr; \
uint64_t __i = (x) ^ (k); \
__yl \
= CAMELLIA_SP1110( __i & 0xff) \
^ CAMELLIA_SP0222((__i >> 24) & 0xff) \
^ CAMELLIA_SP3033((__i >> 16) & 0xff) \
^ CAMELLIA_SP4404((__i >> 8) & 0xff); \
__yr \
= CAMELLIA_SP1110( __i >> 56) \
^ CAMELLIA_SP0222((__i >> 48) & 0xff) \
^ CAMELLIA_SP3033((__i >> 40) & 0xff) \ ^ CAMELLIA_SP4404((__i >> 32) & 0xff); \
__yl ^= __yr; \
__yr = ROL32(24, __yr); \
__yr ^= __yl; \
(y) = ((uint64_t) __yl << 32) | __yr; \
} while (0)
#if ! HAVE_NATIVE_64_BIT
#define CAMELLIA_F_HALF_INV(x) do { \
uint32_t __t, __w; \
__t = (x) >> 32; \
__w = __t ^(x); \
__w = ROL32(8, __w); \
(x) = ((uint64_t) __w << 32) | (__t ^ __w); \
} while (0)
#endif
void
camellia_set_encrypt_key(struct camellia_ctx *ctx,
unsigned length, const uint8_t *key)
{
uint64_t k0, k1;
uint64_t subkey[34];
uint64_t w, kw2, kw4;
uint32_t dw, tl, tr;
unsigned i;
k0 = READ_UINT64(key);
k1 = READ_UINT64(key + 8);
if (length == 16)
{
ctx->nkeys = 24;
/**
* generate KL dependent subkeys
*/
subkey[0] = k0; subkey[1] = k1;
ROL128(15, k0, k1);
subkey[4] = k0; subkey[5] = k1;
ROL128(30, k0, k1);
subkey[10] = k0; subkey[11] = k1;
ROL128(15, k0, k1);
subkey[13] = k1;
ROL128(17, k0, k1);
subkey[16] = k0; subkey[17] = k1;
ROL128(17, k0, k1);
subkey[18] = k0; subkey[19] = k1;
ROL128(17, k0, k1);
subkey[22] = k0; subkey[23] = k1;
/* generate KA. D1 is k0, d2 is k1. */
/* FIXME: Make notation match the spec better. */
/* For the 128-bit case, KR = 0, the construction of KA reduces to:
D1 = KL >> 64;
W = KL & MASK64;
D2 = F(D1, Sigma1);
W = D2 ^ W
D1 = F(W, Sigma2)
D2 = D2 ^ F(D1, Sigma3);
D1 = D1 ^ F(D2, Sigma4);
KA = (D1 << 64) | D2;
*/
k0 = subkey[0]; w = subkey[1];
CAMELLIA_F(k0, SIGMA1, k1);
w ^= k1;
CAMELLIA_F(w, SIGMA2, k0);
CAMELLIA_F(k0, SIGMA3, w); k1 ^= w;
CAMELLIA_F(k1, SIGMA4, w);
k0 ^= w;
/* generate KA dependent subkeys */
subkey[2] = k0; subkey[3] = k1;
ROL128(15, k0, k1);
subkey[6] = k0; subkey[7] = k1;
ROL128(15, k0, k1);
subkey[8] = k0; subkey[9] = k1;
ROL128(15, k0, k1);
subkey[12] = k0;
ROL128(15, k0, k1);
subkey[14] = k0; subkey[15] = k1;
ROL128(34, k0, k1);
subkey[20] = k0; subkey[21] = k1;
ROL128(17, k0, k1);
subkey[24] = k0; subkey[25] = k1;
}
else
{
uint64_t k2, k3;
ctx->nkeys = 32;
k2 = READ_UINT64(key + 16);
if (length == 24)
k3 = ~k2;
else
{
assert (length == 32);
k3 = READ_UINT64(key + 24);
}
/* generate KL dependent subkeys */
subkey[0] = k0; subkey[1] = k1;
ROL128(45, k0, k1);
subkey[12] = k0; subkey[13] = k1;
ROL128(15, k0, k1);
subkey[16] = k0; subkey[17] = k1;
ROL128(17, k0, k1);
subkey[22] = k0; subkey[23] = k1;
ROL128(34, k0, k1);
subkey[30] = k0; subkey[31] = k1;
/* generate KR dependent subkeys */
ROL128(15, k2, k3);
subkey[4] = k2; subkey[5] = k3;
ROL128(15, k2, k3);
subkey[8] = k2; subkey[9] = k3;
ROL128(30, k2, k3);
subkey[18] = k2; subkey[19] = k3;
ROL128(34, k2, k3);
subkey[26] = k2; subkey[27] = k3;
ROL128(34, k2, k3);
/* generate KA */
/* The construction of KA is done as
D1 = (KL ^ KR) >> 64
D2 = (KL ^ KR) & MASK64
W = F(D1, SIGMA1)
D2 = D2 ^ W
D1 = F(D2, SIGMA2) ^ (KR >> 64)
D2 = F(D1, SIGMA3) ^ W ^ (KR & MASK64)
D1 = D1 ^ F(W, SIGMA2)
D2 = D2 ^ F(D1, SIGMA3)
D1 = D1 ^ F(D2, SIGMA4)
*/
k0 = subkey[0] ^ k2; k1 = subkey[1] ^ k3;
CAMELLIA_F(k0, SIGMA1, w);
k1 ^= w;
CAMELLIA_F(k1, SIGMA2, k0);
k0 ^= k2;
CAMELLIA_F(k0, SIGMA3, k1);
k1 ^= w ^ k3;
CAMELLIA_F(k1, SIGMA4, w);
k0 ^= w;
/* generate KB */
k2 ^= k0; k3 ^= k1;
CAMELLIA_F(k2, SIGMA5, w);
k3 ^= w;
CAMELLIA_F(k3, SIGMA6, w);
k2 ^= w;
/* generate KA dependent subkeys */
ROL128(15, k0, k1);
subkey[6] = k0; subkey[7] = k1;
ROL128(30, k0, k1);
subkey[14] = k0; subkey[15] = k1;
ROL128(32, k0, k1);
subkey[24] = k0; subkey[25] = k1;
ROL128(17, k0, k1);
subkey[28] = k0; subkey[29] = k1;
/* generate KB dependent subkeys */
subkey[2] = k2; subkey[3] = k3;
ROL128(30, k2, k3);
subkey[10] = k2; subkey[11] = k3;
ROL128(30, k2, k3);
subkey[20] = k2; subkey[21] = k3;
ROL128(51, k2, k3);
subkey[32] = k2; subkey[33] = k3;
}
/* At this point, the subkey array contains the subkeys as described
in the spec, 26 for short keys and 34 for large keys. */
/* absorb kw2 to other subkeys */
kw2 = subkey[1];
subkey[3] ^= kw2;
subkey[5] ^= kw2;
subkey[7] ^= kw2;
for (i = 8; i < ctx->nkeys; i += 8)
{
/* FIXME: gcc for x86_32 is smart enough to fetch the 32 low bits
and xor the result into the 32 high bits, but it still generates
worse code than for explicit 32-bit operations. */
kw2 ^= (kw2 & ~subkey[i+1]) << 32;
dw = (kw2 & subkey[i+1]) >> 32; kw2 ^= ROL32(1, dw);
subkey[i+3] ^= kw2;
subkey[i+5] ^= kw2;
subkey[i+7] ^= kw2;
}
subkey[i] ^= kw2;
/* absorb kw4 to other subkeys */
kw4 = subkey[ctx->nkeys + 1];
for (i = ctx->nkeys - 8; i > 0; i -= 8)
{
subkey[i+6] ^= kw4; subkey[i+4] ^= kw4;
subkey[i+2] ^= kw4;
kw4 ^= (kw4 & ~subkey[i]) << 32;
dw = (kw4 & subkey[i]) >> 32; kw4 ^= ROL32(1, dw);
}
subkey[6] ^= kw4;
subkey[4] ^= kw4;
subkey[2] ^= kw4;
subkey[0] ^= kw4;
/* key XOR is end of F-function */
ctx->keys[0] = subkey[0] ^ subkey[2];
ctx->keys[1] = subkey[3];
ctx->keys[2] = subkey[2] ^ subkey[4];
ctx->keys[3] = subkey[3] ^ subkey[5];
ctx->keys[4] = subkey[4] ^ subkey[6];
ctx->keys[5] = subkey[5] ^ subkey[7];
for (i = 8; i < ctx->nkeys; i += 8)
{
tl = (subkey[i+2] >> 32) ^ (subkey[i+2] & ~subkey[i]);
dw = tl & (subkey[i] >> 32);
tr = subkey[i+2] ^ ROL32(1, dw);
ctx->keys[i-2] = subkey[i-2] ^ ( ((uint64_t) tl << 32) | tr);
ctx->keys[i-1] = subkey[i];
ctx->keys[i] = subkey[i+1];
tl = (subkey[i-1] >> 32) ^ (subkey[i-1] & ~subkey[i+1]);
dw = tl & (subkey[i+1] >> 32);
tr = subkey[i-1] ^ ROL32(1, dw);
ctx->keys[i+1] = subkey[i+3] ^ ( ((uint64_t) tl << 32) | tr);
ctx->keys[i+2] = subkey[i+2] ^ subkey[i+4];
ctx->keys[i+3] = subkey[i+3] ^ subkey[i+5];
ctx->keys[i+4] = subkey[i+4] ^ subkey[i+6];
ctx->keys[i+5] = subkey[i+5] ^ subkey[i+7];
}
ctx->keys[i-2] = subkey[i-2];
ctx->keys[i-1] = subkey[i] ^ subkey[i-1];
#if !HAVE_NATIVE_64_BIT
for (i = 0; i < ctx->nkeys; i += 8)
{
/* apply the inverse of the last half of F-function */
CAMELLIA_F_HALF_INV(ctx->keys[i+1]);
CAMELLIA_F_HALF_INV(ctx->keys[i+2]);
CAMELLIA_F_HALF_INV(ctx->keys[i+3]);
CAMELLIA_F_HALF_INV(ctx->keys[i+4]);
CAMELLIA_F_HALF_INV(ctx->keys[i+5]);
CAMELLIA_F_HALF_INV(ctx->keys[i+6]);
}
#endif
}