crypto: x86/twofish - switch to XTS template

Now that the XTS template can wrap accelerated ECB modes, it can be
used to implement Twofish in XTS mode as well, which turns out to
be at least as fast, and sometimes even faster

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>

diff --git a/arch/x86/crypto/twofish-avx-x86_64-asm_64.S b/arch/x86/crypto/twofish-avx-x86_64-asm_64.S
index a5151393bb2f328b84a9c8256919eccbef5f2618..84e61ef036385c190c70858be26dac7a11b0ff2a 100644 (file)
--- a/arch/x86/crypto/twofish-avx-x86_64-asm_64.S
+++ b/arch/x86/crypto/twofish-avx-x86_64-asm_64.S
@@ -19,11 +19,6 @@
 .Lbswap128_mask:
        .byte 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0
 
-.section       .rodata.cst16.xts_gf128mul_and_shl1_mask, "aM", @progbits, 16
-.align 16
-.Lxts_gf128mul_and_shl1_mask:
-       .byte 0x87, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0
-
 .text
 
 /* structure of crypto context */
@@ -406,51 +401,3 @@ SYM_FUNC_START(twofish_ctr_8way)
        FRAME_END
        ret;
 SYM_FUNC_END(twofish_ctr_8way)
-
-SYM_FUNC_START(twofish_xts_enc_8way)
-       /* input:
-        *      %rdi: ctx, CTX
-        *      %rsi: dst
-        *      %rdx: src
-        *      %rcx: iv (t ⊕ αⁿ ∈ GF(2¹²⁸))
-        */
-       FRAME_BEGIN
-
-       movq %rsi, %r11;
-
-       /* regs <= src, dst <= IVs, regs <= regs xor IVs */
-       load_xts_8way(%rcx, %rdx, %rsi, RA1, RB1, RC1, RD1, RA2, RB2, RC2, RD2,
-                     RX0, RX1, RY0, .Lxts_gf128mul_and_shl1_mask);
-
-       call __twofish_enc_blk8;
-
-       /* dst <= regs xor IVs(in dst) */
-       store_xts_8way(%r11, RC1, RD1, RA1, RB1, RC2, RD2, RA2, RB2);
-
-       FRAME_END
-       ret;
-SYM_FUNC_END(twofish_xts_enc_8way)
-
-SYM_FUNC_START(twofish_xts_dec_8way)
-       /* input:
-        *      %rdi: ctx, CTX
-        *      %rsi: dst
-        *      %rdx: src
-        *      %rcx: iv (t ⊕ αⁿ ∈ GF(2¹²⁸))
-        */
-       FRAME_BEGIN
-
-       movq %rsi, %r11;
-
-       /* regs <= src, dst <= IVs, regs <= regs xor IVs */
-       load_xts_8way(%rcx, %rdx, %rsi, RC1, RD1, RA1, RB1, RC2, RD2, RA2, RB2,
-                     RX0, RX1, RY0, .Lxts_gf128mul_and_shl1_mask);
-
-       call __twofish_dec_blk8;
-
-       /* dst <= regs xor IVs(in dst) */
-       store_xts_8way(%r11, RA1, RB1, RC1, RD1, RA2, RB2, RC2, RD2);
-
-       FRAME_END
-       ret;
-SYM_FUNC_END(twofish_xts_dec_8way)

diff --git a/arch/x86/crypto/twofish_avx_glue.c b/arch/x86/crypto/twofish_avx_glue.c
index 2dbc8ce3730e53724b16457f298c6a85c0b2dfa4..7b539bbb108f31b2d557fc17fef907a39371c2da 100644 (file)
--- a/arch/x86/crypto/twofish_avx_glue.c
+++ b/arch/x86/crypto/twofish_avx_glue.c
@@ -15,7 +15,6 @@
 #include <crypto/algapi.h>
 #include <crypto/internal/simd.h>
 #include <crypto/twofish.h>
-#include <crypto/xts.h>
 #include <asm/crypto/glue_helper.h>
 #include <asm/crypto/twofish.h>
 
@@ -29,11 +28,6 @@ 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);
 
-asmlinkage void twofish_xts_enc_8way(const void *ctx, u8 *dst, const u8 *src,
-                                    le128 *iv);
-asmlinkage void twofish_xts_dec_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)
 {
@@ -45,40 +39,6 @@ static inline void twofish_enc_blk_3way(const void *ctx, u8 *dst, const u8 *src)
        __twofish_enc_blk_3way(ctx, dst, src, false);
 }
 
-static void twofish_xts_enc(const void *ctx, u8 *dst, const u8 *src, le128 *iv)
-{
-       glue_xts_crypt_128bit_one(ctx, dst, src, iv, twofish_enc_blk);
-}
-
-static void twofish_xts_dec(const void *ctx, u8 *dst, const u8 *src, le128 *iv)
-{
-       glue_xts_crypt_128bit_one(ctx, dst, src, iv, twofish_dec_blk);
-}
-
-struct twofish_xts_ctx {
-       struct twofish_ctx tweak_ctx;
-       struct twofish_ctx crypt_ctx;
-};
-
-static int xts_twofish_setkey(struct crypto_skcipher *tfm, const u8 *key,
-                             unsigned int keylen)
-{
-       struct twofish_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
-       int err;
-
-       err = xts_verify_key(tfm, key, keylen);
-       if (err)
-               return err;
-
-       /* first half of xts-key is for crypt */
-       err = __twofish_setkey(&ctx->crypt_ctx, key, keylen / 2);
-       if (err)
-               return err;
-
-       /* second half of xts-key is for tweak */
-       return __twofish_setkey(&ctx->tweak_ctx, key + keylen / 2, keylen / 2);
-}
-
 static const struct common_glue_ctx twofish_enc = {
        .num_funcs = 3,
        .fpu_blocks_limit = TWOFISH_PARALLEL_BLOCKS,
@@ -111,19 +71,6 @@ static const struct common_glue_ctx twofish_ctr = {
        } }
 };
 
-static const struct common_glue_ctx twofish_enc_xts = {
-       .num_funcs = 2,
-       .fpu_blocks_limit = TWOFISH_PARALLEL_BLOCKS,
-
-       .funcs = { {
-               .num_blocks = TWOFISH_PARALLEL_BLOCKS,
-               .fn_u = { .xts = twofish_xts_enc_8way }
-       }, {
-               .num_blocks = 1,
-               .fn_u = { .xts = twofish_xts_enc }
-       } }
-};
-
 static const struct common_glue_ctx twofish_dec = {
        .num_funcs = 3,
        .fpu_blocks_limit = TWOFISH_PARALLEL_BLOCKS,
@@ -156,19 +103,6 @@ static const struct common_glue_ctx twofish_dec_cbc = {
        } }
 };
 
-static const struct common_glue_ctx twofish_dec_xts = {
-       .num_funcs = 2,
-       .fpu_blocks_limit = TWOFISH_PARALLEL_BLOCKS,
-
-       .funcs = { {
-               .num_blocks = TWOFISH_PARALLEL_BLOCKS,
-               .fn_u = { .xts = twofish_xts_dec_8way }
-       }, {
-               .num_blocks = 1,
-               .fn_u = { .xts = twofish_xts_dec }
-       } }
-};
-
 static int ecb_encrypt(struct skcipher_request *req)
 {
        return glue_ecb_req_128bit(&twofish_enc, req);
@@ -194,24 +128,6 @@ static int ctr_crypt(struct skcipher_request *req)
        return glue_ctr_req_128bit(&twofish_ctr, req);
 }
 
-static int xts_encrypt(struct skcipher_request *req)
-{
-       struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
-       struct twofish_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
-
-       return glue_xts_req_128bit(&twofish_enc_xts, req, twofish_enc_blk,
-                                  &ctx->tweak_ctx, &ctx->crypt_ctx, false);
-}
-
-static int xts_decrypt(struct skcipher_request *req)
-{
-       struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
-       struct twofish_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
-
-       return glue_xts_req_128bit(&twofish_dec_xts, req, twofish_enc_blk,
-                                  &ctx->tweak_ctx, &ctx->crypt_ctx, true);
-}
-
 static struct skcipher_alg twofish_algs[] = {
        {
                .base.cra_name          = "__ecb(twofish)",
@@ -255,20 +171,6 @@ static struct skcipher_alg twofish_algs[] = {
                .setkey                 = twofish_setkey_skcipher,
                .encrypt                = ctr_crypt,
                .decrypt                = ctr_crypt,
-       }, {
-               .base.cra_name          = "__xts(twofish)",
-               .base.cra_driver_name   = "__xts-twofish-avx",
-               .base.cra_priority      = 400,
-               .base.cra_flags         = CRYPTO_ALG_INTERNAL,
-               .base.cra_blocksize     = TF_BLOCK_SIZE,
-               .base.cra_ctxsize       = sizeof(struct twofish_xts_ctx),
-               .base.cra_module        = THIS_MODULE,
-               .min_keysize            = 2 * TF_MIN_KEY_SIZE,
-               .max_keysize            = 2 * TF_MAX_KEY_SIZE,
-               .ivsize                 = TF_BLOCK_SIZE,
-               .setkey                 = xts_twofish_setkey,
-               .encrypt                = xts_encrypt,
-               .decrypt                = xts_decrypt,
        },
 };
 

diff --git a/crypto/Kconfig b/crypto/Kconfig
index ce69a5ae26b5991f31d9b097a31aba37dd460ec7..7ad9bf84f4a04ee49a90ba4347d487bfbaca14cc 100644 (file)
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -1731,6 +1731,7 @@ config CRYPTO_TWOFISH_AVX_X86_64
        select CRYPTO_TWOFISH_COMMON
        select CRYPTO_TWOFISH_X86_64
        select CRYPTO_TWOFISH_X86_64_3WAY
+       imply CRYPTO_XTS
        help
          Twofish cipher algorithm (x86_64/AVX).