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>

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 84e61ef..37e63b3 100644 (file)
--- a/arch/x86/crypto/twofish-avx-x86_64-asm_64.S
+++ b/arch/x86/crypto/twofish-avx-x86_64-asm_64.S
@@ -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)

diff --git a/arch/x86/crypto/twofish_avx_glue.c b/arch/x86/crypto/twofish_avx_glue.c
index 7b539bb..13f810b 100644 (file)
--- a/arch/x86/crypto/twofish_avx_glue.c
+++ b/arch/x86/crypto/twofish_avx_glue.c
@@ -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,
        },
 };
 

diff --git a/arch/x86/crypto/twofish_glue_3way.c b/arch/x86/crypto/twofish_glue_3way.c
index 768af60..8825237 100644 (file)
--- a/arch/x86/crypto/twofish_glue_3way.c
+++ b/arch/x86/crypto/twofish_glue_3way.c
@@ -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,
        },
 };
 

diff --git a/arch/x86/include/asm/crypto/twofish.h b/arch/x86/include/asm/crypto/twofish.h
index 2c377a8..12df400 100644 (file)
--- a/arch/x86/include/asm/crypto/twofish.h
+++ b/arch/x86/include/asm/crypto/twofish.h
@@ -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 */

diff --git a/crypto/Kconfig b/crypto/Kconfig
index 3f51c5d..606f940 100644 (file)
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -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).