linux-brain/crypto/cast6_generic.c
Kees Cook eeb0899e00 crypto: x86 - Regularize glue function prototypes
commit 9c1e8836edbbaf3656bc07437b59c04be034ac4e upstream.

The crypto glue performed function prototype casting via macros to make
indirect calls to assembly routines. Instead of performing casts at the
call sites (which trips Control Flow Integrity prototype checking), switch
each prototype to a common standard set of arguments which allows the
removal of the existing macros. In order to keep pointer math unchanged,
internal casting between u128 pointers and u8 pointers is added.

Co-developed-by: João Moreira <joao.moreira@intel.com>
Signed-off-by: João Moreira <joao.moreira@intel.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Ard Biesheuvel <ardb@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-20 10:39:47 +01:00

290 lines
9.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/* Kernel cryptographic api.
* cast6.c - Cast6 cipher algorithm [rfc2612].
*
* CAST-256 (*cast6*) is a DES like Substitution-Permutation Network (SPN)
* cryptosystem built upon the CAST-128 (*cast5*) [rfc2144] encryption
* algorithm.
*
* Copyright (C) 2003 Kartikey Mahendra Bhatt <kartik_me@hotmail.com>.
*/
#include <asm/byteorder.h>
#include <linux/init.h>
#include <linux/crypto.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/types.h>
#include <crypto/cast6.h>
#define s1 cast_s1
#define s2 cast_s2
#define s3 cast_s3
#define s4 cast_s4
#define F1(D, r, m) ((I = ((m) + (D))), (I = rol32(I, (r))), \
(((s1[I >> 24] ^ s2[(I>>16)&0xff]) - s3[(I>>8)&0xff]) + s4[I&0xff]))
#define F2(D, r, m) ((I = ((m) ^ (D))), (I = rol32(I, (r))), \
(((s1[I >> 24] - s2[(I>>16)&0xff]) + s3[(I>>8)&0xff]) ^ s4[I&0xff]))
#define F3(D, r, m) ((I = ((m) - (D))), (I = rol32(I, (r))), \
(((s1[I >> 24] + s2[(I>>16)&0xff]) ^ s3[(I>>8)&0xff]) - s4[I&0xff]))
static const u32 Tm[24][8] = {
{ 0x5a827999, 0xc95c653a, 0x383650db, 0xa7103c7c, 0x15ea281d,
0x84c413be, 0xf39dff5f, 0x6277eb00 } ,
{ 0xd151d6a1, 0x402bc242, 0xaf05ade3, 0x1ddf9984, 0x8cb98525,
0xfb9370c6, 0x6a6d5c67, 0xd9474808 } ,
{ 0x482133a9, 0xb6fb1f4a, 0x25d50aeb, 0x94aef68c, 0x0388e22d,
0x7262cdce, 0xe13cb96f, 0x5016a510 } ,
{ 0xbef090b1, 0x2dca7c52, 0x9ca467f3, 0x0b7e5394, 0x7a583f35,
0xe9322ad6, 0x580c1677, 0xc6e60218 } ,
{ 0x35bfedb9, 0xa499d95a, 0x1373c4fb, 0x824db09c, 0xf1279c3d,
0x600187de, 0xcedb737f, 0x3db55f20 } ,
{ 0xac8f4ac1, 0x1b693662, 0x8a432203, 0xf91d0da4, 0x67f6f945,
0xd6d0e4e6, 0x45aad087, 0xb484bc28 } ,
{ 0x235ea7c9, 0x9238936a, 0x01127f0b, 0x6fec6aac, 0xdec6564d,
0x4da041ee, 0xbc7a2d8f, 0x2b541930 } ,
{ 0x9a2e04d1, 0x0907f072, 0x77e1dc13, 0xe6bbc7b4, 0x5595b355,
0xc46f9ef6, 0x33498a97, 0xa2237638 } ,
{ 0x10fd61d9, 0x7fd74d7a, 0xeeb1391b, 0x5d8b24bc, 0xcc65105d,
0x3b3efbfe, 0xaa18e79f, 0x18f2d340 } ,
{ 0x87ccbee1, 0xf6a6aa82, 0x65809623, 0xd45a81c4, 0x43346d65,
0xb20e5906, 0x20e844a7, 0x8fc23048 } ,
{ 0xfe9c1be9, 0x6d76078a, 0xdc4ff32b, 0x4b29decc, 0xba03ca6d,
0x28ddb60e, 0x97b7a1af, 0x06918d50 } ,
{ 0x756b78f1, 0xe4456492, 0x531f5033, 0xc1f93bd4, 0x30d32775,
0x9fad1316, 0x0e86feb7, 0x7d60ea58 } ,
{ 0xec3ad5f9, 0x5b14c19a, 0xc9eead3b, 0x38c898dc, 0xa7a2847d,
0x167c701e, 0x85565bbf, 0xf4304760 } ,
{ 0x630a3301, 0xd1e41ea2, 0x40be0a43, 0xaf97f5e4, 0x1e71e185,
0x8d4bcd26, 0xfc25b8c7, 0x6affa468 } ,
{ 0xd9d99009, 0x48b37baa, 0xb78d674b, 0x266752ec, 0x95413e8d,
0x041b2a2e, 0x72f515cf, 0xe1cf0170 } ,
{ 0x50a8ed11, 0xbf82d8b2, 0x2e5cc453, 0x9d36aff4, 0x0c109b95,
0x7aea8736, 0xe9c472d7, 0x589e5e78 } ,
{ 0xc7784a19, 0x365235ba, 0xa52c215b, 0x14060cfc, 0x82dff89d,
0xf1b9e43e, 0x6093cfdf, 0xcf6dbb80 } ,
{ 0x3e47a721, 0xad2192c2, 0x1bfb7e63, 0x8ad56a04, 0xf9af55a5,
0x68894146, 0xd7632ce7, 0x463d1888 } ,
{ 0xb5170429, 0x23f0efca, 0x92cadb6b, 0x01a4c70c, 0x707eb2ad,
0xdf589e4e, 0x4e3289ef, 0xbd0c7590 } ,
{ 0x2be66131, 0x9ac04cd2, 0x099a3873, 0x78742414, 0xe74e0fb5,
0x5627fb56, 0xc501e6f7, 0x33dbd298 } ,
{ 0xa2b5be39, 0x118fa9da, 0x8069957b, 0xef43811c, 0x5e1d6cbd,
0xccf7585e, 0x3bd143ff, 0xaaab2fa0 } ,
{ 0x19851b41, 0x885f06e2, 0xf738f283, 0x6612de24, 0xd4ecc9c5,
0x43c6b566, 0xb2a0a107, 0x217a8ca8 } ,
{ 0x90547849, 0xff2e63ea, 0x6e084f8b, 0xdce23b2c, 0x4bbc26cd,
0xba96126e, 0x296ffe0f, 0x9849e9b0 } ,
{ 0x0723d551, 0x75fdc0f2, 0xe4d7ac93, 0x53b19834, 0xc28b83d5,
0x31656f76, 0xa03f5b17, 0x0f1946b8 }
};
static const u8 Tr[4][8] = {
{ 0x13, 0x04, 0x15, 0x06, 0x17, 0x08, 0x19, 0x0a } ,
{ 0x1b, 0x0c, 0x1d, 0x0e, 0x1f, 0x10, 0x01, 0x12 } ,
{ 0x03, 0x14, 0x05, 0x16, 0x07, 0x18, 0x09, 0x1a } ,
{ 0x0b, 0x1c, 0x0d, 0x1e, 0x0f, 0x00, 0x11, 0x02 }
};
/* forward octave */
static inline void W(u32 *key, unsigned int i)
{
u32 I;
key[6] ^= F1(key[7], Tr[i % 4][0], Tm[i][0]);
key[5] ^= F2(key[6], Tr[i % 4][1], Tm[i][1]);
key[4] ^= F3(key[5], Tr[i % 4][2], Tm[i][2]);
key[3] ^= F1(key[4], Tr[i % 4][3], Tm[i][3]);
key[2] ^= F2(key[3], Tr[i % 4][4], Tm[i][4]);
key[1] ^= F3(key[2], Tr[i % 4][5], Tm[i][5]);
key[0] ^= F1(key[1], Tr[i % 4][6], Tm[i][6]);
key[7] ^= F2(key[0], Tr[i % 4][7], Tm[i][7]);
}
int __cast6_setkey(struct cast6_ctx *c, const u8 *in_key,
unsigned key_len, u32 *flags)
{
int i;
u32 key[8];
__be32 p_key[8]; /* padded key */
if (key_len % 4 != 0) {
*flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
return -EINVAL;
}
memset(p_key, 0, 32);
memcpy(p_key, in_key, key_len);
key[0] = be32_to_cpu(p_key[0]); /* A */
key[1] = be32_to_cpu(p_key[1]); /* B */
key[2] = be32_to_cpu(p_key[2]); /* C */
key[3] = be32_to_cpu(p_key[3]); /* D */
key[4] = be32_to_cpu(p_key[4]); /* E */
key[5] = be32_to_cpu(p_key[5]); /* F */
key[6] = be32_to_cpu(p_key[6]); /* G */
key[7] = be32_to_cpu(p_key[7]); /* H */
for (i = 0; i < 12; i++) {
W(key, 2 * i);
W(key, 2 * i + 1);
c->Kr[i][0] = key[0] & 0x1f;
c->Kr[i][1] = key[2] & 0x1f;
c->Kr[i][2] = key[4] & 0x1f;
c->Kr[i][3] = key[6] & 0x1f;
c->Km[i][0] = key[7];
c->Km[i][1] = key[5];
c->Km[i][2] = key[3];
c->Km[i][3] = key[1];
}
return 0;
}
EXPORT_SYMBOL_GPL(__cast6_setkey);
int cast6_setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
{
return __cast6_setkey(crypto_tfm_ctx(tfm), key, keylen,
&tfm->crt_flags);
}
EXPORT_SYMBOL_GPL(cast6_setkey);
/*forward quad round*/
static inline void Q(u32 *block, const u8 *Kr, const u32 *Km)
{
u32 I;
block[2] ^= F1(block[3], Kr[0], Km[0]);
block[1] ^= F2(block[2], Kr[1], Km[1]);
block[0] ^= F3(block[1], Kr[2], Km[2]);
block[3] ^= F1(block[0], Kr[3], Km[3]);
}
/*reverse quad round*/
static inline void QBAR(u32 *block, const u8 *Kr, const u32 *Km)
{
u32 I;
block[3] ^= F1(block[0], Kr[3], Km[3]);
block[0] ^= F3(block[1], Kr[2], Km[2]);
block[1] ^= F2(block[2], Kr[1], Km[1]);
block[2] ^= F1(block[3], Kr[0], Km[0]);
}
void __cast6_encrypt(const void *ctx, u8 *outbuf, const u8 *inbuf)
{
const struct cast6_ctx *c = ctx;
const __be32 *src = (const __be32 *)inbuf;
__be32 *dst = (__be32 *)outbuf;
u32 block[4];
const u32 *Km;
const u8 *Kr;
block[0] = be32_to_cpu(src[0]);
block[1] = be32_to_cpu(src[1]);
block[2] = be32_to_cpu(src[2]);
block[3] = be32_to_cpu(src[3]);
Km = c->Km[0]; Kr = c->Kr[0]; Q(block, Kr, Km);
Km = c->Km[1]; Kr = c->Kr[1]; Q(block, Kr, Km);
Km = c->Km[2]; Kr = c->Kr[2]; Q(block, Kr, Km);
Km = c->Km[3]; Kr = c->Kr[3]; Q(block, Kr, Km);
Km = c->Km[4]; Kr = c->Kr[4]; Q(block, Kr, Km);
Km = c->Km[5]; Kr = c->Kr[5]; Q(block, Kr, Km);
Km = c->Km[6]; Kr = c->Kr[6]; QBAR(block, Kr, Km);
Km = c->Km[7]; Kr = c->Kr[7]; QBAR(block, Kr, Km);
Km = c->Km[8]; Kr = c->Kr[8]; QBAR(block, Kr, Km);
Km = c->Km[9]; Kr = c->Kr[9]; QBAR(block, Kr, Km);
Km = c->Km[10]; Kr = c->Kr[10]; QBAR(block, Kr, Km);
Km = c->Km[11]; Kr = c->Kr[11]; QBAR(block, Kr, Km);
dst[0] = cpu_to_be32(block[0]);
dst[1] = cpu_to_be32(block[1]);
dst[2] = cpu_to_be32(block[2]);
dst[3] = cpu_to_be32(block[3]);
}
EXPORT_SYMBOL_GPL(__cast6_encrypt);
static void cast6_encrypt(struct crypto_tfm *tfm, u8 *outbuf, const u8 *inbuf)
{
__cast6_encrypt(crypto_tfm_ctx(tfm), outbuf, inbuf);
}
void __cast6_decrypt(const void *ctx, u8 *outbuf, const u8 *inbuf)
{
const struct cast6_ctx *c = ctx;
const __be32 *src = (const __be32 *)inbuf;
__be32 *dst = (__be32 *)outbuf;
u32 block[4];
const u32 *Km;
const u8 *Kr;
block[0] = be32_to_cpu(src[0]);
block[1] = be32_to_cpu(src[1]);
block[2] = be32_to_cpu(src[2]);
block[3] = be32_to_cpu(src[3]);
Km = c->Km[11]; Kr = c->Kr[11]; Q(block, Kr, Km);
Km = c->Km[10]; Kr = c->Kr[10]; Q(block, Kr, Km);
Km = c->Km[9]; Kr = c->Kr[9]; Q(block, Kr, Km);
Km = c->Km[8]; Kr = c->Kr[8]; Q(block, Kr, Km);
Km = c->Km[7]; Kr = c->Kr[7]; Q(block, Kr, Km);
Km = c->Km[6]; Kr = c->Kr[6]; Q(block, Kr, Km);
Km = c->Km[5]; Kr = c->Kr[5]; QBAR(block, Kr, Km);
Km = c->Km[4]; Kr = c->Kr[4]; QBAR(block, Kr, Km);
Km = c->Km[3]; Kr = c->Kr[3]; QBAR(block, Kr, Km);
Km = c->Km[2]; Kr = c->Kr[2]; QBAR(block, Kr, Km);
Km = c->Km[1]; Kr = c->Kr[1]; QBAR(block, Kr, Km);
Km = c->Km[0]; Kr = c->Kr[0]; QBAR(block, Kr, Km);
dst[0] = cpu_to_be32(block[0]);
dst[1] = cpu_to_be32(block[1]);
dst[2] = cpu_to_be32(block[2]);
dst[3] = cpu_to_be32(block[3]);
}
EXPORT_SYMBOL_GPL(__cast6_decrypt);
static void cast6_decrypt(struct crypto_tfm *tfm, u8 *outbuf, const u8 *inbuf)
{
__cast6_decrypt(crypto_tfm_ctx(tfm), outbuf, inbuf);
}
static struct crypto_alg alg = {
.cra_name = "cast6",
.cra_driver_name = "cast6-generic",
.cra_priority = 100,
.cra_flags = CRYPTO_ALG_TYPE_CIPHER,
.cra_blocksize = CAST6_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct cast6_ctx),
.cra_alignmask = 3,
.cra_module = THIS_MODULE,
.cra_u = {
.cipher = {
.cia_min_keysize = CAST6_MIN_KEY_SIZE,
.cia_max_keysize = CAST6_MAX_KEY_SIZE,
.cia_setkey = cast6_setkey,
.cia_encrypt = cast6_encrypt,
.cia_decrypt = cast6_decrypt}
}
};
static int __init cast6_mod_init(void)
{
return crypto_register_alg(&alg);
}
static void __exit cast6_mod_fini(void)
{
crypto_unregister_alg(&alg);
}
subsys_initcall(cast6_mod_init);
module_exit(cast6_mod_fini);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Cast6 Cipher Algorithm");
MODULE_ALIAS_CRYPTO("cast6");
MODULE_ALIAS_CRYPTO("cast6-generic");