linux-hardened/crypto/serpent_generic.c
Arnd Bergmann c871c10e4e crypto: serpent - improve __serpent_setkey with UBSAN
When UBSAN is enabled, we get a very large stack frame for
__serpent_setkey, when the register allocator ends up using more registers
than it has, and has to spill temporary values to the stack. The code
was originally optimized for in-order x86-32 CPU implementations using
older compilers, but it now runs into a highly suboptimal case on all
CPU architectures, as seen by this warning:

crypto/serpent_generic.c: In function '__serpent_setkey':
crypto/serpent_generic.c:436:1: error: the frame size of 2720 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]

Disabling -fsanitize=alignment would avoid that warning, presumably the
option turns off a optimization step that is required for getting the
register allocation right, but there is no easy way to do that on gcc-7
(gcc-8 introduces a function attribute for this).

I tried to figure out a way to modify the source code instead, and noticed
that the two stages of the setkey() function (keyiter and sbox) each are
fine by themselves, but not when combined into one function. Splitting
out the entire sbox into a separate function also happens to work fine
with all compilers I tried (arm, arm64 and x86).

The setkey function uses a strange way to handle offsets into the key
array, using both negative and positive index values, as well as adjusting
the array pointer back and forth. I have checked that this actually
makes no difference to modern compilers, but I left that untouched
to make the patch easier to review and to keep the code closer to
the reference implementation.

Link: https://patchwork.kernel.org/patch/9189575/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-08-09 20:17:54 +08:00

675 lines
21 KiB
C

/*
* Cryptographic API.
*
* Serpent Cipher Algorithm.
*
* Copyright (C) 2002 Dag Arne Osvik <osvik@ii.uib.no>
* 2003 Herbert Valerio Riedel <hvr@gnu.org>
*
* Added tnepres support:
* Ruben Jesus Garcia Hernandez <ruben@ugr.es>, 18.10.2004
* Based on code by hvr
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <asm/byteorder.h>
#include <linux/crypto.h>
#include <linux/types.h>
#include <crypto/serpent.h>
/* Key is padded to the maximum of 256 bits before round key generation.
* Any key length <= 256 bits (32 bytes) is allowed by the algorithm.
*/
#define PHI 0x9e3779b9UL
#define keyiter(a, b, c, d, i, j) \
({ b ^= d; b ^= c; b ^= a; b ^= PHI ^ i; b = rol32(b, 11); k[j] = b; })
#define loadkeys(x0, x1, x2, x3, i) \
({ x0 = k[i]; x1 = k[i+1]; x2 = k[i+2]; x3 = k[i+3]; })
#define storekeys(x0, x1, x2, x3, i) \
({ k[i] = x0; k[i+1] = x1; k[i+2] = x2; k[i+3] = x3; })
#define store_and_load_keys(x0, x1, x2, x3, s, l) \
({ storekeys(x0, x1, x2, x3, s); loadkeys(x0, x1, x2, x3, l); })
#define K(x0, x1, x2, x3, i) ({ \
x3 ^= k[4*(i)+3]; x2 ^= k[4*(i)+2]; \
x1 ^= k[4*(i)+1]; x0 ^= k[4*(i)+0]; \
})
#define LK(x0, x1, x2, x3, x4, i) ({ \
x0 = rol32(x0, 13);\
x2 = rol32(x2, 3); x1 ^= x0; x4 = x0 << 3; \
x3 ^= x2; x1 ^= x2; \
x1 = rol32(x1, 1); x3 ^= x4; \
x3 = rol32(x3, 7); x4 = x1; \
x0 ^= x1; x4 <<= 7; x2 ^= x3; \
x0 ^= x3; x2 ^= x4; x3 ^= k[4*i+3]; \
x1 ^= k[4*i+1]; x0 = rol32(x0, 5); x2 = rol32(x2, 22);\
x0 ^= k[4*i+0]; x2 ^= k[4*i+2]; \
})
#define KL(x0, x1, x2, x3, x4, i) ({ \
x0 ^= k[4*i+0]; x1 ^= k[4*i+1]; x2 ^= k[4*i+2]; \
x3 ^= k[4*i+3]; x0 = ror32(x0, 5); x2 = ror32(x2, 22);\
x4 = x1; x2 ^= x3; x0 ^= x3; \
x4 <<= 7; x0 ^= x1; x1 = ror32(x1, 1); \
x2 ^= x4; x3 = ror32(x3, 7); x4 = x0 << 3; \
x1 ^= x0; x3 ^= x4; x0 = ror32(x0, 13);\
x1 ^= x2; x3 ^= x2; x2 = ror32(x2, 3); \
})
#define S0(x0, x1, x2, x3, x4) ({ \
x4 = x3; \
x3 |= x0; x0 ^= x4; x4 ^= x2; \
x4 = ~x4; x3 ^= x1; x1 &= x0; \
x1 ^= x4; x2 ^= x0; x0 ^= x3; \
x4 |= x0; x0 ^= x2; x2 &= x1; \
x3 ^= x2; x1 = ~x1; x2 ^= x4; \
x1 ^= x2; \
})
#define S1(x0, x1, x2, x3, x4) ({ \
x4 = x1; \
x1 ^= x0; x0 ^= x3; x3 = ~x3; \
x4 &= x1; x0 |= x1; x3 ^= x2; \
x0 ^= x3; x1 ^= x3; x3 ^= x4; \
x1 |= x4; x4 ^= x2; x2 &= x0; \
x2 ^= x1; x1 |= x0; x0 = ~x0; \
x0 ^= x2; x4 ^= x1; \
})
#define S2(x0, x1, x2, x3, x4) ({ \
x3 = ~x3; \
x1 ^= x0; x4 = x0; x0 &= x2; \
x0 ^= x3; x3 |= x4; x2 ^= x1; \
x3 ^= x1; x1 &= x0; x0 ^= x2; \
x2 &= x3; x3 |= x1; x0 = ~x0; \
x3 ^= x0; x4 ^= x0; x0 ^= x2; \
x1 |= x2; \
})
#define S3(x0, x1, x2, x3, x4) ({ \
x4 = x1; \
x1 ^= x3; x3 |= x0; x4 &= x0; \
x0 ^= x2; x2 ^= x1; x1 &= x3; \
x2 ^= x3; x0 |= x4; x4 ^= x3; \
x1 ^= x0; x0 &= x3; x3 &= x4; \
x3 ^= x2; x4 |= x1; x2 &= x1; \
x4 ^= x3; x0 ^= x3; x3 ^= x2; \
})
#define S4(x0, x1, x2, x3, x4) ({ \
x4 = x3; \
x3 &= x0; x0 ^= x4; \
x3 ^= x2; x2 |= x4; x0 ^= x1; \
x4 ^= x3; x2 |= x0; \
x2 ^= x1; x1 &= x0; \
x1 ^= x4; x4 &= x2; x2 ^= x3; \
x4 ^= x0; x3 |= x1; x1 = ~x1; \
x3 ^= x0; \
})
#define S5(x0, x1, x2, x3, x4) ({ \
x4 = x1; x1 |= x0; \
x2 ^= x1; x3 = ~x3; x4 ^= x0; \
x0 ^= x2; x1 &= x4; x4 |= x3; \
x4 ^= x0; x0 &= x3; x1 ^= x3; \
x3 ^= x2; x0 ^= x1; x2 &= x4; \
x1 ^= x2; x2 &= x0; \
x3 ^= x2; \
})
#define S6(x0, x1, x2, x3, x4) ({ \
x4 = x1; \
x3 ^= x0; x1 ^= x2; x2 ^= x0; \
x0 &= x3; x1 |= x3; x4 = ~x4; \
x0 ^= x1; x1 ^= x2; \
x3 ^= x4; x4 ^= x0; x2 &= x0; \
x4 ^= x1; x2 ^= x3; x3 &= x1; \
x3 ^= x0; x1 ^= x2; \
})
#define S7(x0, x1, x2, x3, x4) ({ \
x1 = ~x1; \
x4 = x1; x0 = ~x0; x1 &= x2; \
x1 ^= x3; x3 |= x4; x4 ^= x2; \
x2 ^= x3; x3 ^= x0; x0 |= x1; \
x2 &= x0; x0 ^= x4; x4 ^= x3; \
x3 &= x0; x4 ^= x1; \
x2 ^= x4; x3 ^= x1; x4 |= x0; \
x4 ^= x1; \
})
#define SI0(x0, x1, x2, x3, x4) ({ \
x4 = x3; x1 ^= x0; \
x3 |= x1; x4 ^= x1; x0 = ~x0; \
x2 ^= x3; x3 ^= x0; x0 &= x1; \
x0 ^= x2; x2 &= x3; x3 ^= x4; \
x2 ^= x3; x1 ^= x3; x3 &= x0; \
x1 ^= x0; x0 ^= x2; x4 ^= x3; \
})
#define SI1(x0, x1, x2, x3, x4) ({ \
x1 ^= x3; x4 = x0; \
x0 ^= x2; x2 = ~x2; x4 |= x1; \
x4 ^= x3; x3 &= x1; x1 ^= x2; \
x2 &= x4; x4 ^= x1; x1 |= x3; \
x3 ^= x0; x2 ^= x0; x0 |= x4; \
x2 ^= x4; x1 ^= x0; \
x4 ^= x1; \
})
#define SI2(x0, x1, x2, x3, x4) ({ \
x2 ^= x1; x4 = x3; x3 = ~x3; \
x3 |= x2; x2 ^= x4; x4 ^= x0; \
x3 ^= x1; x1 |= x2; x2 ^= x0; \
x1 ^= x4; x4 |= x3; x2 ^= x3; \
x4 ^= x2; x2 &= x1; \
x2 ^= x3; x3 ^= x4; x4 ^= x0; \
})
#define SI3(x0, x1, x2, x3, x4) ({ \
x2 ^= x1; \
x4 = x1; x1 &= x2; \
x1 ^= x0; x0 |= x4; x4 ^= x3; \
x0 ^= x3; x3 |= x1; x1 ^= x2; \
x1 ^= x3; x0 ^= x2; x2 ^= x3; \
x3 &= x1; x1 ^= x0; x0 &= x2; \
x4 ^= x3; x3 ^= x0; x0 ^= x1; \
})
#define SI4(x0, x1, x2, x3, x4) ({ \
x2 ^= x3; x4 = x0; x0 &= x1; \
x0 ^= x2; x2 |= x3; x4 = ~x4; \
x1 ^= x0; x0 ^= x2; x2 &= x4; \
x2 ^= x0; x0 |= x4; \
x0 ^= x3; x3 &= x2; \
x4 ^= x3; x3 ^= x1; x1 &= x0; \
x4 ^= x1; x0 ^= x3; \
})
#define SI5(x0, x1, x2, x3, x4) ({ \
x4 = x1; x1 |= x2; \
x2 ^= x4; x1 ^= x3; x3 &= x4; \
x2 ^= x3; x3 |= x0; x0 = ~x0; \
x3 ^= x2; x2 |= x0; x4 ^= x1; \
x2 ^= x4; x4 &= x0; x0 ^= x1; \
x1 ^= x3; x0 &= x2; x2 ^= x3; \
x0 ^= x2; x2 ^= x4; x4 ^= x3; \
})
#define SI6(x0, x1, x2, x3, x4) ({ \
x0 ^= x2; \
x4 = x0; x0 &= x3; x2 ^= x3; \
x0 ^= x2; x3 ^= x1; x2 |= x4; \
x2 ^= x3; x3 &= x0; x0 = ~x0; \
x3 ^= x1; x1 &= x2; x4 ^= x0; \
x3 ^= x4; x4 ^= x2; x0 ^= x1; \
x2 ^= x0; \
})
#define SI7(x0, x1, x2, x3, x4) ({ \
x4 = x3; x3 &= x0; x0 ^= x2; \
x2 |= x4; x4 ^= x1; x0 = ~x0; \
x1 |= x3; x4 ^= x0; x0 &= x2; \
x0 ^= x1; x1 &= x2; x3 ^= x2; \
x4 ^= x3; x2 &= x3; x3 |= x0; \
x1 ^= x4; x3 ^= x4; x4 &= x0; \
x4 ^= x2; \
})
static void __serpent_setkey_sbox(u32 r0, u32 r1, u32 r2, u32 r3, u32 r4, u32 *k)
{
k += 100;
S3(r3, r4, r0, r1, r2); store_and_load_keys(r1, r2, r4, r3, 28, 24);
S4(r1, r2, r4, r3, r0); store_and_load_keys(r2, r4, r3, r0, 24, 20);
S5(r2, r4, r3, r0, r1); store_and_load_keys(r1, r2, r4, r0, 20, 16);
S6(r1, r2, r4, r0, r3); store_and_load_keys(r4, r3, r2, r0, 16, 12);
S7(r4, r3, r2, r0, r1); store_and_load_keys(r1, r2, r0, r4, 12, 8);
S0(r1, r2, r0, r4, r3); store_and_load_keys(r0, r2, r4, r1, 8, 4);
S1(r0, r2, r4, r1, r3); store_and_load_keys(r3, r4, r1, r0, 4, 0);
S2(r3, r4, r1, r0, r2); store_and_load_keys(r2, r4, r3, r0, 0, -4);
S3(r2, r4, r3, r0, r1); store_and_load_keys(r0, r1, r4, r2, -4, -8);
S4(r0, r1, r4, r2, r3); store_and_load_keys(r1, r4, r2, r3, -8, -12);
S5(r1, r4, r2, r3, r0); store_and_load_keys(r0, r1, r4, r3, -12, -16);
S6(r0, r1, r4, r3, r2); store_and_load_keys(r4, r2, r1, r3, -16, -20);
S7(r4, r2, r1, r3, r0); store_and_load_keys(r0, r1, r3, r4, -20, -24);
S0(r0, r1, r3, r4, r2); store_and_load_keys(r3, r1, r4, r0, -24, -28);
k -= 50;
S1(r3, r1, r4, r0, r2); store_and_load_keys(r2, r4, r0, r3, 22, 18);
S2(r2, r4, r0, r3, r1); store_and_load_keys(r1, r4, r2, r3, 18, 14);
S3(r1, r4, r2, r3, r0); store_and_load_keys(r3, r0, r4, r1, 14, 10);
S4(r3, r0, r4, r1, r2); store_and_load_keys(r0, r4, r1, r2, 10, 6);
S5(r0, r4, r1, r2, r3); store_and_load_keys(r3, r0, r4, r2, 6, 2);
S6(r3, r0, r4, r2, r1); store_and_load_keys(r4, r1, r0, r2, 2, -2);
S7(r4, r1, r0, r2, r3); store_and_load_keys(r3, r0, r2, r4, -2, -6);
S0(r3, r0, r2, r4, r1); store_and_load_keys(r2, r0, r4, r3, -6, -10);
S1(r2, r0, r4, r3, r1); store_and_load_keys(r1, r4, r3, r2, -10, -14);
S2(r1, r4, r3, r2, r0); store_and_load_keys(r0, r4, r1, r2, -14, -18);
S3(r0, r4, r1, r2, r3); store_and_load_keys(r2, r3, r4, r0, -18, -22);
k -= 50;
S4(r2, r3, r4, r0, r1); store_and_load_keys(r3, r4, r0, r1, 28, 24);
S5(r3, r4, r0, r1, r2); store_and_load_keys(r2, r3, r4, r1, 24, 20);
S6(r2, r3, r4, r1, r0); store_and_load_keys(r4, r0, r3, r1, 20, 16);
S7(r4, r0, r3, r1, r2); store_and_load_keys(r2, r3, r1, r4, 16, 12);
S0(r2, r3, r1, r4, r0); store_and_load_keys(r1, r3, r4, r2, 12, 8);
S1(r1, r3, r4, r2, r0); store_and_load_keys(r0, r4, r2, r1, 8, 4);
S2(r0, r4, r2, r1, r3); store_and_load_keys(r3, r4, r0, r1, 4, 0);
S3(r3, r4, r0, r1, r2); storekeys(r1, r2, r4, r3, 0);
}
int __serpent_setkey(struct serpent_ctx *ctx, const u8 *key,
unsigned int keylen)
{
u32 *k = ctx->expkey;
u8 *k8 = (u8 *)k;
u32 r0, r1, r2, r3, r4;
int i;
/* Copy key, add padding */
for (i = 0; i < keylen; ++i)
k8[i] = key[i];
if (i < SERPENT_MAX_KEY_SIZE)
k8[i++] = 1;
while (i < SERPENT_MAX_KEY_SIZE)
k8[i++] = 0;
/* Expand key using polynomial */
r0 = le32_to_cpu(k[3]);
r1 = le32_to_cpu(k[4]);
r2 = le32_to_cpu(k[5]);
r3 = le32_to_cpu(k[6]);
r4 = le32_to_cpu(k[7]);
keyiter(le32_to_cpu(k[0]), r0, r4, r2, 0, 0);
keyiter(le32_to_cpu(k[1]), r1, r0, r3, 1, 1);
keyiter(le32_to_cpu(k[2]), r2, r1, r4, 2, 2);
keyiter(le32_to_cpu(k[3]), r3, r2, r0, 3, 3);
keyiter(le32_to_cpu(k[4]), r4, r3, r1, 4, 4);
keyiter(le32_to_cpu(k[5]), r0, r4, r2, 5, 5);
keyiter(le32_to_cpu(k[6]), r1, r0, r3, 6, 6);
keyiter(le32_to_cpu(k[7]), r2, r1, r4, 7, 7);
keyiter(k[0], r3, r2, r0, 8, 8);
keyiter(k[1], r4, r3, r1, 9, 9);
keyiter(k[2], r0, r4, r2, 10, 10);
keyiter(k[3], r1, r0, r3, 11, 11);
keyiter(k[4], r2, r1, r4, 12, 12);
keyiter(k[5], r3, r2, r0, 13, 13);
keyiter(k[6], r4, r3, r1, 14, 14);
keyiter(k[7], r0, r4, r2, 15, 15);
keyiter(k[8], r1, r0, r3, 16, 16);
keyiter(k[9], r2, r1, r4, 17, 17);
keyiter(k[10], r3, r2, r0, 18, 18);
keyiter(k[11], r4, r3, r1, 19, 19);
keyiter(k[12], r0, r4, r2, 20, 20);
keyiter(k[13], r1, r0, r3, 21, 21);
keyiter(k[14], r2, r1, r4, 22, 22);
keyiter(k[15], r3, r2, r0, 23, 23);
keyiter(k[16], r4, r3, r1, 24, 24);
keyiter(k[17], r0, r4, r2, 25, 25);
keyiter(k[18], r1, r0, r3, 26, 26);
keyiter(k[19], r2, r1, r4, 27, 27);
keyiter(k[20], r3, r2, r0, 28, 28);
keyiter(k[21], r4, r3, r1, 29, 29);
keyiter(k[22], r0, r4, r2, 30, 30);
keyiter(k[23], r1, r0, r3, 31, 31);
k += 50;
keyiter(k[-26], r2, r1, r4, 32, -18);
keyiter(k[-25], r3, r2, r0, 33, -17);
keyiter(k[-24], r4, r3, r1, 34, -16);
keyiter(k[-23], r0, r4, r2, 35, -15);
keyiter(k[-22], r1, r0, r3, 36, -14);
keyiter(k[-21], r2, r1, r4, 37, -13);
keyiter(k[-20], r3, r2, r0, 38, -12);
keyiter(k[-19], r4, r3, r1, 39, -11);
keyiter(k[-18], r0, r4, r2, 40, -10);
keyiter(k[-17], r1, r0, r3, 41, -9);
keyiter(k[-16], r2, r1, r4, 42, -8);
keyiter(k[-15], r3, r2, r0, 43, -7);
keyiter(k[-14], r4, r3, r1, 44, -6);
keyiter(k[-13], r0, r4, r2, 45, -5);
keyiter(k[-12], r1, r0, r3, 46, -4);
keyiter(k[-11], r2, r1, r4, 47, -3);
keyiter(k[-10], r3, r2, r0, 48, -2);
keyiter(k[-9], r4, r3, r1, 49, -1);
keyiter(k[-8], r0, r4, r2, 50, 0);
keyiter(k[-7], r1, r0, r3, 51, 1);
keyiter(k[-6], r2, r1, r4, 52, 2);
keyiter(k[-5], r3, r2, r0, 53, 3);
keyiter(k[-4], r4, r3, r1, 54, 4);
keyiter(k[-3], r0, r4, r2, 55, 5);
keyiter(k[-2], r1, r0, r3, 56, 6);
keyiter(k[-1], r2, r1, r4, 57, 7);
keyiter(k[0], r3, r2, r0, 58, 8);
keyiter(k[1], r4, r3, r1, 59, 9);
keyiter(k[2], r0, r4, r2, 60, 10);
keyiter(k[3], r1, r0, r3, 61, 11);
keyiter(k[4], r2, r1, r4, 62, 12);
keyiter(k[5], r3, r2, r0, 63, 13);
keyiter(k[6], r4, r3, r1, 64, 14);
keyiter(k[7], r0, r4, r2, 65, 15);
keyiter(k[8], r1, r0, r3, 66, 16);
keyiter(k[9], r2, r1, r4, 67, 17);
keyiter(k[10], r3, r2, r0, 68, 18);
keyiter(k[11], r4, r3, r1, 69, 19);
keyiter(k[12], r0, r4, r2, 70, 20);
keyiter(k[13], r1, r0, r3, 71, 21);
keyiter(k[14], r2, r1, r4, 72, 22);
keyiter(k[15], r3, r2, r0, 73, 23);
keyiter(k[16], r4, r3, r1, 74, 24);
keyiter(k[17], r0, r4, r2, 75, 25);
keyiter(k[18], r1, r0, r3, 76, 26);
keyiter(k[19], r2, r1, r4, 77, 27);
keyiter(k[20], r3, r2, r0, 78, 28);
keyiter(k[21], r4, r3, r1, 79, 29);
keyiter(k[22], r0, r4, r2, 80, 30);
keyiter(k[23], r1, r0, r3, 81, 31);
k += 50;
keyiter(k[-26], r2, r1, r4, 82, -18);
keyiter(k[-25], r3, r2, r0, 83, -17);
keyiter(k[-24], r4, r3, r1, 84, -16);
keyiter(k[-23], r0, r4, r2, 85, -15);
keyiter(k[-22], r1, r0, r3, 86, -14);
keyiter(k[-21], r2, r1, r4, 87, -13);
keyiter(k[-20], r3, r2, r0, 88, -12);
keyiter(k[-19], r4, r3, r1, 89, -11);
keyiter(k[-18], r0, r4, r2, 90, -10);
keyiter(k[-17], r1, r0, r3, 91, -9);
keyiter(k[-16], r2, r1, r4, 92, -8);
keyiter(k[-15], r3, r2, r0, 93, -7);
keyiter(k[-14], r4, r3, r1, 94, -6);
keyiter(k[-13], r0, r4, r2, 95, -5);
keyiter(k[-12], r1, r0, r3, 96, -4);
keyiter(k[-11], r2, r1, r4, 97, -3);
keyiter(k[-10], r3, r2, r0, 98, -2);
keyiter(k[-9], r4, r3, r1, 99, -1);
keyiter(k[-8], r0, r4, r2, 100, 0);
keyiter(k[-7], r1, r0, r3, 101, 1);
keyiter(k[-6], r2, r1, r4, 102, 2);
keyiter(k[-5], r3, r2, r0, 103, 3);
keyiter(k[-4], r4, r3, r1, 104, 4);
keyiter(k[-3], r0, r4, r2, 105, 5);
keyiter(k[-2], r1, r0, r3, 106, 6);
keyiter(k[-1], r2, r1, r4, 107, 7);
keyiter(k[0], r3, r2, r0, 108, 8);
keyiter(k[1], r4, r3, r1, 109, 9);
keyiter(k[2], r0, r4, r2, 110, 10);
keyiter(k[3], r1, r0, r3, 111, 11);
keyiter(k[4], r2, r1, r4, 112, 12);
keyiter(k[5], r3, r2, r0, 113, 13);
keyiter(k[6], r4, r3, r1, 114, 14);
keyiter(k[7], r0, r4, r2, 115, 15);
keyiter(k[8], r1, r0, r3, 116, 16);
keyiter(k[9], r2, r1, r4, 117, 17);
keyiter(k[10], r3, r2, r0, 118, 18);
keyiter(k[11], r4, r3, r1, 119, 19);
keyiter(k[12], r0, r4, r2, 120, 20);
keyiter(k[13], r1, r0, r3, 121, 21);
keyiter(k[14], r2, r1, r4, 122, 22);
keyiter(k[15], r3, r2, r0, 123, 23);
keyiter(k[16], r4, r3, r1, 124, 24);
keyiter(k[17], r0, r4, r2, 125, 25);
keyiter(k[18], r1, r0, r3, 126, 26);
keyiter(k[19], r2, r1, r4, 127, 27);
keyiter(k[20], r3, r2, r0, 128, 28);
keyiter(k[21], r4, r3, r1, 129, 29);
keyiter(k[22], r0, r4, r2, 130, 30);
keyiter(k[23], r1, r0, r3, 131, 31);
/* Apply S-boxes */
__serpent_setkey_sbox(r0, r1, r2, r3, r4, ctx->expkey);
return 0;
}
EXPORT_SYMBOL_GPL(__serpent_setkey);
int serpent_setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
{
return __serpent_setkey(crypto_tfm_ctx(tfm), key, keylen);
}
EXPORT_SYMBOL_GPL(serpent_setkey);
void __serpent_encrypt(struct serpent_ctx *ctx, u8 *dst, const u8 *src)
{
const u32 *k = ctx->expkey;
const __le32 *s = (const __le32 *)src;
__le32 *d = (__le32 *)dst;
u32 r0, r1, r2, r3, r4;
/*
* Note: The conversions between u8* and u32* might cause trouble
* on architectures with stricter alignment rules than x86
*/
r0 = le32_to_cpu(s[0]);
r1 = le32_to_cpu(s[1]);
r2 = le32_to_cpu(s[2]);
r3 = le32_to_cpu(s[3]);
K(r0, r1, r2, r3, 0);
S0(r0, r1, r2, r3, r4); LK(r2, r1, r3, r0, r4, 1);
S1(r2, r1, r3, r0, r4); LK(r4, r3, r0, r2, r1, 2);
S2(r4, r3, r0, r2, r1); LK(r1, r3, r4, r2, r0, 3);
S3(r1, r3, r4, r2, r0); LK(r2, r0, r3, r1, r4, 4);
S4(r2, r0, r3, r1, r4); LK(r0, r3, r1, r4, r2, 5);
S5(r0, r3, r1, r4, r2); LK(r2, r0, r3, r4, r1, 6);
S6(r2, r0, r3, r4, r1); LK(r3, r1, r0, r4, r2, 7);
S7(r3, r1, r0, r4, r2); LK(r2, r0, r4, r3, r1, 8);
S0(r2, r0, r4, r3, r1); LK(r4, r0, r3, r2, r1, 9);
S1(r4, r0, r3, r2, r1); LK(r1, r3, r2, r4, r0, 10);
S2(r1, r3, r2, r4, r0); LK(r0, r3, r1, r4, r2, 11);
S3(r0, r3, r1, r4, r2); LK(r4, r2, r3, r0, r1, 12);
S4(r4, r2, r3, r0, r1); LK(r2, r3, r0, r1, r4, 13);
S5(r2, r3, r0, r1, r4); LK(r4, r2, r3, r1, r0, 14);
S6(r4, r2, r3, r1, r0); LK(r3, r0, r2, r1, r4, 15);
S7(r3, r0, r2, r1, r4); LK(r4, r2, r1, r3, r0, 16);
S0(r4, r2, r1, r3, r0); LK(r1, r2, r3, r4, r0, 17);
S1(r1, r2, r3, r4, r0); LK(r0, r3, r4, r1, r2, 18);
S2(r0, r3, r4, r1, r2); LK(r2, r3, r0, r1, r4, 19);
S3(r2, r3, r0, r1, r4); LK(r1, r4, r3, r2, r0, 20);
S4(r1, r4, r3, r2, r0); LK(r4, r3, r2, r0, r1, 21);
S5(r4, r3, r2, r0, r1); LK(r1, r4, r3, r0, r2, 22);
S6(r1, r4, r3, r0, r2); LK(r3, r2, r4, r0, r1, 23);
S7(r3, r2, r4, r0, r1); LK(r1, r4, r0, r3, r2, 24);
S0(r1, r4, r0, r3, r2); LK(r0, r4, r3, r1, r2, 25);
S1(r0, r4, r3, r1, r2); LK(r2, r3, r1, r0, r4, 26);
S2(r2, r3, r1, r0, r4); LK(r4, r3, r2, r0, r1, 27);
S3(r4, r3, r2, r0, r1); LK(r0, r1, r3, r4, r2, 28);
S4(r0, r1, r3, r4, r2); LK(r1, r3, r4, r2, r0, 29);
S5(r1, r3, r4, r2, r0); LK(r0, r1, r3, r2, r4, 30);
S6(r0, r1, r3, r2, r4); LK(r3, r4, r1, r2, r0, 31);
S7(r3, r4, r1, r2, r0); K(r0, r1, r2, r3, 32);
d[0] = cpu_to_le32(r0);
d[1] = cpu_to_le32(r1);
d[2] = cpu_to_le32(r2);
d[3] = cpu_to_le32(r3);
}
EXPORT_SYMBOL_GPL(__serpent_encrypt);
static void serpent_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
struct serpent_ctx *ctx = crypto_tfm_ctx(tfm);
__serpent_encrypt(ctx, dst, src);
}
void __serpent_decrypt(struct serpent_ctx *ctx, u8 *dst, const u8 *src)
{
const u32 *k = ctx->expkey;
const __le32 *s = (const __le32 *)src;
__le32 *d = (__le32 *)dst;
u32 r0, r1, r2, r3, r4;
r0 = le32_to_cpu(s[0]);
r1 = le32_to_cpu(s[1]);
r2 = le32_to_cpu(s[2]);
r3 = le32_to_cpu(s[3]);
K(r0, r1, r2, r3, 32);
SI7(r0, r1, r2, r3, r4); KL(r1, r3, r0, r4, r2, 31);
SI6(r1, r3, r0, r4, r2); KL(r0, r2, r4, r1, r3, 30);
SI5(r0, r2, r4, r1, r3); KL(r2, r3, r0, r4, r1, 29);
SI4(r2, r3, r0, r4, r1); KL(r2, r0, r1, r4, r3, 28);
SI3(r2, r0, r1, r4, r3); KL(r1, r2, r3, r4, r0, 27);
SI2(r1, r2, r3, r4, r0); KL(r2, r0, r4, r3, r1, 26);
SI1(r2, r0, r4, r3, r1); KL(r1, r0, r4, r3, r2, 25);
SI0(r1, r0, r4, r3, r2); KL(r4, r2, r0, r1, r3, 24);
SI7(r4, r2, r0, r1, r3); KL(r2, r1, r4, r3, r0, 23);
SI6(r2, r1, r4, r3, r0); KL(r4, r0, r3, r2, r1, 22);
SI5(r4, r0, r3, r2, r1); KL(r0, r1, r4, r3, r2, 21);
SI4(r0, r1, r4, r3, r2); KL(r0, r4, r2, r3, r1, 20);
SI3(r0, r4, r2, r3, r1); KL(r2, r0, r1, r3, r4, 19);
SI2(r2, r0, r1, r3, r4); KL(r0, r4, r3, r1, r2, 18);
SI1(r0, r4, r3, r1, r2); KL(r2, r4, r3, r1, r0, 17);
SI0(r2, r4, r3, r1, r0); KL(r3, r0, r4, r2, r1, 16);
SI7(r3, r0, r4, r2, r1); KL(r0, r2, r3, r1, r4, 15);
SI6(r0, r2, r3, r1, r4); KL(r3, r4, r1, r0, r2, 14);
SI5(r3, r4, r1, r0, r2); KL(r4, r2, r3, r1, r0, 13);
SI4(r4, r2, r3, r1, r0); KL(r4, r3, r0, r1, r2, 12);
SI3(r4, r3, r0, r1, r2); KL(r0, r4, r2, r1, r3, 11);
SI2(r0, r4, r2, r1, r3); KL(r4, r3, r1, r2, r0, 10);
SI1(r4, r3, r1, r2, r0); KL(r0, r3, r1, r2, r4, 9);
SI0(r0, r3, r1, r2, r4); KL(r1, r4, r3, r0, r2, 8);
SI7(r1, r4, r3, r0, r2); KL(r4, r0, r1, r2, r3, 7);
SI6(r4, r0, r1, r2, r3); KL(r1, r3, r2, r4, r0, 6);
SI5(r1, r3, r2, r4, r0); KL(r3, r0, r1, r2, r4, 5);
SI4(r3, r0, r1, r2, r4); KL(r3, r1, r4, r2, r0, 4);
SI3(r3, r1, r4, r2, r0); KL(r4, r3, r0, r2, r1, 3);
SI2(r4, r3, r0, r2, r1); KL(r3, r1, r2, r0, r4, 2);
SI1(r3, r1, r2, r0, r4); KL(r4, r1, r2, r0, r3, 1);
SI0(r4, r1, r2, r0, r3); K(r2, r3, r1, r4, 0);
d[0] = cpu_to_le32(r2);
d[1] = cpu_to_le32(r3);
d[2] = cpu_to_le32(r1);
d[3] = cpu_to_le32(r4);
}
EXPORT_SYMBOL_GPL(__serpent_decrypt);
static void serpent_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
struct serpent_ctx *ctx = crypto_tfm_ctx(tfm);
__serpent_decrypt(ctx, dst, src);
}
static int tnepres_setkey(struct crypto_tfm *tfm, const u8 *key,
unsigned int keylen)
{
u8 rev_key[SERPENT_MAX_KEY_SIZE];
int i;
for (i = 0; i < keylen; ++i)
rev_key[keylen - i - 1] = key[i];
return serpent_setkey(tfm, rev_key, keylen);
}
static void tnepres_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
const u32 * const s = (const u32 * const)src;
u32 * const d = (u32 * const)dst;
u32 rs[4], rd[4];
rs[0] = swab32(s[3]);
rs[1] = swab32(s[2]);
rs[2] = swab32(s[1]);
rs[3] = swab32(s[0]);
serpent_encrypt(tfm, (u8 *)rd, (u8 *)rs);
d[0] = swab32(rd[3]);
d[1] = swab32(rd[2]);
d[2] = swab32(rd[1]);
d[3] = swab32(rd[0]);
}
static void tnepres_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
const u32 * const s = (const u32 * const)src;
u32 * const d = (u32 * const)dst;
u32 rs[4], rd[4];
rs[0] = swab32(s[3]);
rs[1] = swab32(s[2]);
rs[2] = swab32(s[1]);
rs[3] = swab32(s[0]);
serpent_decrypt(tfm, (u8 *)rd, (u8 *)rs);
d[0] = swab32(rd[3]);
d[1] = swab32(rd[2]);
d[2] = swab32(rd[1]);
d[3] = swab32(rd[0]);
}
static struct crypto_alg srp_algs[2] = { {
.cra_name = "serpent",
.cra_driver_name = "serpent-generic",
.cra_priority = 100,
.cra_flags = CRYPTO_ALG_TYPE_CIPHER,
.cra_blocksize = SERPENT_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct serpent_ctx),
.cra_alignmask = 3,
.cra_module = THIS_MODULE,
.cra_u = { .cipher = {
.cia_min_keysize = SERPENT_MIN_KEY_SIZE,
.cia_max_keysize = SERPENT_MAX_KEY_SIZE,
.cia_setkey = serpent_setkey,
.cia_encrypt = serpent_encrypt,
.cia_decrypt = serpent_decrypt } }
}, {
.cra_name = "tnepres",
.cra_flags = CRYPTO_ALG_TYPE_CIPHER,
.cra_blocksize = SERPENT_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct serpent_ctx),
.cra_alignmask = 3,
.cra_module = THIS_MODULE,
.cra_u = { .cipher = {
.cia_min_keysize = SERPENT_MIN_KEY_SIZE,
.cia_max_keysize = SERPENT_MAX_KEY_SIZE,
.cia_setkey = tnepres_setkey,
.cia_encrypt = tnepres_encrypt,
.cia_decrypt = tnepres_decrypt } }
} };
static int __init serpent_mod_init(void)
{
return crypto_register_algs(srp_algs, ARRAY_SIZE(srp_algs));
}
static void __exit serpent_mod_fini(void)
{
crypto_unregister_algs(srp_algs, ARRAY_SIZE(srp_algs));
}
module_init(serpent_mod_init);
module_exit(serpent_mod_fini);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Serpent and tnepres (kerneli compatible serpent reversed) Cipher Algorithm");
MODULE_AUTHOR("Dag Arne Osvik <osvik@ii.uib.no>");
MODULE_ALIAS_CRYPTO("tnepres");
MODULE_ALIAS_CRYPTO("serpent");
MODULE_ALIAS_CRYPTO("serpent-generic");