Commit 7a6623cc authored by Ard Biesheuvel's avatar Ard Biesheuvel Committed by Herbert Xu
Browse files

crypto: x86/cast6 - drop CTR mode implementation 



CAST6 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: default avatarEric Biggers <ebiggers@google.com>
Signed-off-by: default avatarArd Biesheuvel <ardb@kernel.org>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent e2d60e2f

arch/x86/crypto/cast6-avx-x86_64-asm_64.S

+0 −28
Original line number Diff line number Diff line
@@ -410,31 +410,3 @@ SYM_FUNC_START(cast6_cbc_dec_8way) 
	FRAME_END

	ret;

SYM_FUNC_END(cast6_cbc_dec_8way)
 


SYM_FUNC_START(cast6_ctr_8way)

	/* input:

	 *	%rdi: ctx, CTX

	 *	%rsi: dst

	 *	%rdx: src

	 *	%rcx: iv (little endian, 128bit)

	 */

	FRAME_BEGIN

	pushq %r12;

	pushq %r15



	movq %rdi, CTX;

	movq %rsi, %r11;

	movq %rdx, %r12;



	load_ctr_8way(%rcx, .Lbswap128_mask, RA1, RB1, RC1, RD1, RA2, RB2, RC2,

		      RD2, RX, RKR, RKM);



	call __cast6_enc_blk8;



	store_ctr_8way(%r12, %r11, RA1, RB1, RC1, RD1, RA2, RB2, RC2, RD2);



	popq %r15;

	popq %r12;

	FRAME_END

	ret;

SYM_FUNC_END(cast6_ctr_8way)

arch/x86/crypto/cast6_avx_glue.c

+0 −48
Original line number Diff line number Diff line
@@ -23,8 +23,6 @@ asmlinkage void cast6_ecb_enc_8way(const void *ctx, u8 *dst, const u8 *src); 
asmlinkage void cast6_ecb_dec_8way(const void *ctx, u8 *dst, const u8 *src);



asmlinkage void cast6_cbc_dec_8way(const void *ctx, u8 *dst, const u8 *src);

asmlinkage void cast6_ctr_8way(const void *ctx, u8 *dst, const u8 *src,

			       le128 *iv);



static int cast6_setkey_skcipher(struct crypto_skcipher *tfm,

				 const u8 *key, unsigned int keylen)
@@ -32,19 +30,6 @@ static int cast6_setkey_skcipher(struct crypto_skcipher *tfm, 
	return cast6_setkey(&tfm->base, key, keylen);

}



static void cast6_crypt_ctr(const void *ctx, u8 *d, const u8 *s, le128 *iv)

{

	be128 ctrblk;

	u128 *dst = (u128 *)d;

	const u128 *src = (const u128 *)s;



	le128_to_be128(&ctrblk, iv);

	le128_inc(iv);



	__cast6_encrypt(ctx, (u8 *)&ctrblk, (u8 *)&ctrblk);

	u128_xor(dst, src, (u128 *)&ctrblk);

}



static const struct common_glue_ctx cast6_enc = {

	.num_funcs = 2,

	.fpu_blocks_limit = CAST6_PARALLEL_BLOCKS,
@@ -58,19 +43,6 @@ static const struct common_glue_ctx cast6_enc = { 
	} }

};



static const struct common_glue_ctx cast6_ctr = {

	.num_funcs = 2,

	.fpu_blocks_limit = CAST6_PARALLEL_BLOCKS,



	.funcs = { {

		.num_blocks = CAST6_PARALLEL_BLOCKS,

		.fn_u = { .ctr = cast6_ctr_8way }

	}, {

		.num_blocks = 1,

		.fn_u = { .ctr = cast6_crypt_ctr }

	} }

};



static const struct common_glue_ctx cast6_dec = {

	.num_funcs = 2,

	.fpu_blocks_limit = CAST6_PARALLEL_BLOCKS,
@@ -117,11 +89,6 @@ static int cbc_decrypt(struct skcipher_request *req) 
	return glue_cbc_decrypt_req_128bit(&cast6_dec_cbc, req);

}



static int ctr_crypt(struct skcipher_request *req)

{

	return glue_ctr_req_128bit(&cast6_ctr, req);

}



static struct skcipher_alg cast6_algs[] = {

	{

		.base.cra_name		= "__ecb(cast6)",
@@ -150,21 +117,6 @@ static struct skcipher_alg cast6_algs[] = { 
		.setkey			= cast6_setkey_skcipher,

		.encrypt		= cbc_encrypt,

		.decrypt		= cbc_decrypt,

	}, {

		.base.cra_name		= "__ctr(cast6)",

		.base.cra_driver_name	= "__ctr-cast6-avx",

		.base.cra_priority	= 200,

		.base.cra_flags		= CRYPTO_ALG_INTERNAL,

		.base.cra_blocksize	= 1,

		.base.cra_ctxsize	= sizeof(struct cast6_ctx),

		.base.cra_module	= THIS_MODULE,

		.min_keysize		= CAST6_MIN_KEY_SIZE,

		.max_keysize		= CAST6_MAX_KEY_SIZE,

		.ivsize			= CAST6_BLOCK_SIZE,

		.chunksize		= CAST6_BLOCK_SIZE,

		.setkey			= cast6_setkey_skcipher,

		.encrypt		= ctr_crypt,

		.decrypt		= ctr_crypt,

	},

};

crypto/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -1397,6 +1397,7 @@ config CRYPTO_CAST6_AVX_X86_64 
	select CRYPTO_GLUE_HELPER_X86

	select CRYPTO_SIMD

	imply CRYPTO_XTS

	imply CRYPTO_CTR

	help

	  The CAST6 encryption algorithm (synonymous with CAST-256) is

	  described in RFC2612.