crypto: x86/twofish - drop CTR mode implementation

Twofish in CTR mode is never used by the kernel directly, and is highly
unlikely to be relied upon by dm-crypt or algif_skcipher. So let's drop
the accelerated CTR mode implementation, and instead, rely on the CTR
template and the bare cipher.

Acked-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Ard Biesheuvel 2021-01-05 17:47:58 +01:00 committed by Herbert Xu
parent 7a6623cc68
commit f43dcaf2c9
5 changed files with 2 additions and 147 deletions

View File

@ -374,30 +374,3 @@ SYM_FUNC_START(twofish_cbc_dec_8way)
FRAME_END
ret;
SYM_FUNC_END(twofish_cbc_dec_8way)
SYM_FUNC_START(twofish_ctr_8way)
/* input:
* %rdi: ctx, CTX
* %rsi: dst
* %rdx: src
* %rcx: iv (little endian, 128bit)
*/
FRAME_BEGIN
pushq %r12;
movq %rsi, %r11;
movq %rdx, %r12;
load_ctr_8way(%rcx, .Lbswap128_mask, RA1, RB1, RC1, RD1, RA2, RB2, RC2,
RD2, RX0, RX1, RY0);
call __twofish_enc_blk8;
store_ctr_8way(%r12, %r11, RC1, RD1, RA1, RB1, RC2, RD2, RA2, RB2);
popq %r12;
FRAME_END
ret;
SYM_FUNC_END(twofish_ctr_8way)

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@ -25,8 +25,6 @@ asmlinkage void twofish_ecb_enc_8way(const void *ctx, u8 *dst, const u8 *src);
asmlinkage void twofish_ecb_dec_8way(const void *ctx, u8 *dst, const u8 *src);
asmlinkage void twofish_cbc_dec_8way(const void *ctx, u8 *dst, const u8 *src);
asmlinkage void twofish_ctr_8way(const void *ctx, u8 *dst, const u8 *src,
le128 *iv);
static int twofish_setkey_skcipher(struct crypto_skcipher *tfm,
const u8 *key, unsigned int keylen)
@ -55,22 +53,6 @@ static const struct common_glue_ctx twofish_enc = {
} }
};
static const struct common_glue_ctx twofish_ctr = {
.num_funcs = 3,
.fpu_blocks_limit = TWOFISH_PARALLEL_BLOCKS,
.funcs = { {
.num_blocks = TWOFISH_PARALLEL_BLOCKS,
.fn_u = { .ctr = twofish_ctr_8way }
}, {
.num_blocks = 3,
.fn_u = { .ctr = twofish_enc_blk_ctr_3way }
}, {
.num_blocks = 1,
.fn_u = { .ctr = twofish_enc_blk_ctr }
} }
};
static const struct common_glue_ctx twofish_dec = {
.num_funcs = 3,
.fpu_blocks_limit = TWOFISH_PARALLEL_BLOCKS,
@ -123,11 +105,6 @@ static int cbc_decrypt(struct skcipher_request *req)
return glue_cbc_decrypt_req_128bit(&twofish_dec_cbc, req);
}
static int ctr_crypt(struct skcipher_request *req)
{
return glue_ctr_req_128bit(&twofish_ctr, req);
}
static struct skcipher_alg twofish_algs[] = {
{
.base.cra_name = "__ecb(twofish)",
@ -156,21 +133,6 @@ static struct skcipher_alg twofish_algs[] = {
.setkey = twofish_setkey_skcipher,
.encrypt = cbc_encrypt,
.decrypt = cbc_decrypt,
}, {
.base.cra_name = "__ctr(twofish)",
.base.cra_driver_name = "__ctr-twofish-avx",
.base.cra_priority = 400,
.base.cra_flags = CRYPTO_ALG_INTERNAL,
.base.cra_blocksize = 1,
.base.cra_ctxsize = sizeof(struct twofish_ctx),
.base.cra_module = THIS_MODULE,
.min_keysize = TF_MIN_KEY_SIZE,
.max_keysize = TF_MAX_KEY_SIZE,
.ivsize = TF_BLOCK_SIZE,
.chunksize = TF_BLOCK_SIZE,
.setkey = twofish_setkey_skcipher,
.encrypt = ctr_crypt,
.decrypt = ctr_crypt,
},
};

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@ -30,12 +30,6 @@ static inline void twofish_enc_blk_3way(const void *ctx, u8 *dst, const u8 *src)
__twofish_enc_blk_3way(ctx, dst, src, false);
}
static inline void twofish_enc_blk_xor_3way(const void *ctx, u8 *dst,
const u8 *src)
{
__twofish_enc_blk_3way(ctx, dst, src, true);
}
void twofish_dec_blk_cbc_3way(const void *ctx, u8 *d, const u8 *s)
{
u128 ivs[2];
@ -52,46 +46,6 @@ void twofish_dec_blk_cbc_3way(const void *ctx, u8 *d, const u8 *s)
}
EXPORT_SYMBOL_GPL(twofish_dec_blk_cbc_3way);
void twofish_enc_blk_ctr(const void *ctx, u8 *d, const u8 *s, le128 *iv)
{
be128 ctrblk;
u128 *dst = (u128 *)d;
const u128 *src = (const u128 *)s;
if (dst != src)
*dst = *src;
le128_to_be128(&ctrblk, iv);
le128_inc(iv);
twofish_enc_blk(ctx, (u8 *)&ctrblk, (u8 *)&ctrblk);
u128_xor(dst, dst, (u128 *)&ctrblk);
}
EXPORT_SYMBOL_GPL(twofish_enc_blk_ctr);
void twofish_enc_blk_ctr_3way(const void *ctx, u8 *d, const u8 *s, le128 *iv)
{
be128 ctrblks[3];
u128 *dst = (u128 *)d;
const u128 *src = (const u128 *)s;
if (dst != src) {
dst[0] = src[0];
dst[1] = src[1];
dst[2] = src[2];
}
le128_to_be128(&ctrblks[0], iv);
le128_inc(iv);
le128_to_be128(&ctrblks[1], iv);
le128_inc(iv);
le128_to_be128(&ctrblks[2], iv);
le128_inc(iv);
twofish_enc_blk_xor_3way(ctx, (u8 *)dst, (u8 *)ctrblks);
}
EXPORT_SYMBOL_GPL(twofish_enc_blk_ctr_3way);
static const struct common_glue_ctx twofish_enc = {
.num_funcs = 2,
.fpu_blocks_limit = -1,
@ -105,19 +59,6 @@ static const struct common_glue_ctx twofish_enc = {
} }
};
static const struct common_glue_ctx twofish_ctr = {
.num_funcs = 2,
.fpu_blocks_limit = -1,
.funcs = { {
.num_blocks = 3,
.fn_u = { .ctr = twofish_enc_blk_ctr_3way }
}, {
.num_blocks = 1,
.fn_u = { .ctr = twofish_enc_blk_ctr }
} }
};
static const struct common_glue_ctx twofish_dec = {
.num_funcs = 2,
.fpu_blocks_limit = -1,
@ -164,11 +105,6 @@ static int cbc_decrypt(struct skcipher_request *req)
return glue_cbc_decrypt_req_128bit(&twofish_dec_cbc, req);
}
static int ctr_crypt(struct skcipher_request *req)
{
return glue_ctr_req_128bit(&twofish_ctr, req);
}
static struct skcipher_alg tf_skciphers[] = {
{
.base.cra_name = "ecb(twofish)",
@ -195,20 +131,6 @@ static struct skcipher_alg tf_skciphers[] = {
.setkey = twofish_setkey_skcipher,
.encrypt = cbc_encrypt,
.decrypt = cbc_decrypt,
}, {
.base.cra_name = "ctr(twofish)",
.base.cra_driver_name = "ctr-twofish-3way",
.base.cra_priority = 300,
.base.cra_blocksize = 1,
.base.cra_ctxsize = sizeof(struct twofish_ctx),
.base.cra_module = THIS_MODULE,
.min_keysize = TF_MIN_KEY_SIZE,
.max_keysize = TF_MAX_KEY_SIZE,
.ivsize = TF_BLOCK_SIZE,
.chunksize = TF_BLOCK_SIZE,
.setkey = twofish_setkey_skcipher,
.encrypt = ctr_crypt,
.decrypt = ctr_crypt,
},
};

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@ -17,9 +17,5 @@ asmlinkage void twofish_dec_blk_3way(const void *ctx, u8 *dst, const u8 *src);
/* helpers from twofish_x86_64-3way module */
extern void twofish_dec_blk_cbc_3way(const void *ctx, u8 *dst, const u8 *src);
extern void twofish_enc_blk_ctr(const void *ctx, u8 *dst, const u8 *src,
le128 *iv);
extern void twofish_enc_blk_ctr_3way(const void *ctx, u8 *dst, const u8 *src,
le128 *iv);
#endif /* ASM_X86_TWOFISH_H */

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@ -1680,6 +1680,7 @@ config CRYPTO_TWOFISH_586
depends on (X86 || UML_X86) && !64BIT
select CRYPTO_ALGAPI
select CRYPTO_TWOFISH_COMMON
imply CRYPTO_CTR
help
Twofish cipher algorithm.
@ -1696,6 +1697,7 @@ config CRYPTO_TWOFISH_X86_64
depends on (X86 || UML_X86) && 64BIT
select CRYPTO_ALGAPI
select CRYPTO_TWOFISH_COMMON
imply CRYPTO_CTR
help
Twofish cipher algorithm (x86_64).