| Message ID | 20191212093008.217086-3-Jason@zx2c4.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [crypto-next,v2,1/3] crypto: poly1305 - add new 32 and 64-bit generic versions | expand |
On Thu, 12 Dec 2019 at 10:30, Jason A. Donenfeld <Jason@zx2c4.com> wrote: > > This appears to be some kind of copy and paste error, and is actually > dead code. > > Pre: f = 0 ⇒ (f >> 32) = 0 > f = (f >> 32) + le32_to_cpu(digest[0]); > Post: 0 ≤ f < 2³² > put_unaligned_le32(f, dst); > > Pre: 0 ≤ f < 2³² ⇒ (f >> 32) = 0 > f = (f >> 32) + le32_to_cpu(digest[1]); > Post: 0 ≤ f < 2³² > put_unaligned_le32(f, dst + 4); > > Pre: 0 ≤ f < 2³² ⇒ (f >> 32) = 0 > f = (f >> 32) + le32_to_cpu(digest[2]); > Post: 0 ≤ f < 2³² > put_unaligned_le32(f, dst + 8); > > Pre: 0 ≤ f < 2³² ⇒ (f >> 32) = 0 > f = (f >> 32) + le32_to_cpu(digest[3]); > Post: 0 ≤ f < 2³² > put_unaligned_le32(f, dst + 12); > > Therefore this sequence is redundant. And Andy's code appears to handle > misalignment acceptably. > > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> > Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> > --- The change is obviously correct, but I ran it on a big-endian system just to be sure. Tested-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> > arch/arm/crypto/poly1305-glue.c | 18 ++---------------- > arch/arm64/crypto/poly1305-glue.c | 18 ++---------------- > arch/mips/crypto/poly1305-glue.c | 18 ++---------------- > 3 files changed, 6 insertions(+), 48 deletions(-) > > diff --git a/arch/arm/crypto/poly1305-glue.c b/arch/arm/crypto/poly1305-glue.c > index abe3f2d587dc..ceec04ec2f40 100644 > --- a/arch/arm/crypto/poly1305-glue.c > +++ b/arch/arm/crypto/poly1305-glue.c > @@ -20,7 +20,7 @@ > > void poly1305_init_arm(void *state, const u8 *key); > void poly1305_blocks_arm(void *state, const u8 *src, u32 len, u32 hibit); > -void poly1305_emit_arm(void *state, __le32 *digest, const u32 *nonce); > +void poly1305_emit_arm(void *state, u8 *digest, const u32 *nonce); > > void __weak poly1305_blocks_neon(void *state, const u8 *src, u32 len, u32 hibit) > { > @@ -179,9 +179,6 @@ EXPORT_SYMBOL(poly1305_update_arch); > > void poly1305_final_arch(struct poly1305_desc_ctx *dctx, u8 *dst) > { > - __le32 digest[4]; > - u64 f = 0; > - > if (unlikely(dctx->buflen)) { > dctx->buf[dctx->buflen++] = 1; > memset(dctx->buf + dctx->buflen, 0, > @@ -189,18 +186,7 @@ void poly1305_final_arch(struct poly1305_desc_ctx *dctx, u8 *dst) > poly1305_blocks_arm(&dctx->h, dctx->buf, POLY1305_BLOCK_SIZE, 0); > } > > - poly1305_emit_arm(&dctx->h, digest, dctx->s); > - > - /* mac = (h + s) % (2^128) */ > - f = (f >> 32) + le32_to_cpu(digest[0]); > - put_unaligned_le32(f, dst); > - f = (f >> 32) + le32_to_cpu(digest[1]); > - put_unaligned_le32(f, dst + 4); > - f = (f >> 32) + le32_to_cpu(digest[2]); > - put_unaligned_le32(f, dst + 8); > - f = (f >> 32) + le32_to_cpu(digest[3]); > - put_unaligned_le32(f, dst + 12); > - > + poly1305_emit_arm(&dctx->h, dst, dctx->s); > *dctx = (struct poly1305_desc_ctx){}; > } > EXPORT_SYMBOL(poly1305_final_arch); > diff --git a/arch/arm64/crypto/poly1305-glue.c b/arch/arm64/crypto/poly1305-glue.c > index 83a2338a8826..e97b092f56b8 100644 > --- a/arch/arm64/crypto/poly1305-glue.c > +++ b/arch/arm64/crypto/poly1305-glue.c > @@ -21,7 +21,7 @@ > asmlinkage void poly1305_init_arm64(void *state, const u8 *key); > asmlinkage void poly1305_blocks(void *state, const u8 *src, u32 len, u32 hibit); > asmlinkage void poly1305_blocks_neon(void *state, const u8 *src, u32 len, u32 hibit); > -asmlinkage void poly1305_emit(void *state, __le32 *digest, const u32 *nonce); > +asmlinkage void poly1305_emit(void *state, u8 *digest, const u32 *nonce); > > static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_neon); > > @@ -162,9 +162,6 @@ EXPORT_SYMBOL(poly1305_update_arch); > > void poly1305_final_arch(struct poly1305_desc_ctx *dctx, u8 *dst) > { > - __le32 digest[4]; > - u64 f = 0; > - > if (unlikely(dctx->buflen)) { > dctx->buf[dctx->buflen++] = 1; > memset(dctx->buf + dctx->buflen, 0, > @@ -172,18 +169,7 @@ void poly1305_final_arch(struct poly1305_desc_ctx *dctx, u8 *dst) > poly1305_blocks(&dctx->h, dctx->buf, POLY1305_BLOCK_SIZE, 0); > } > > - poly1305_emit(&dctx->h, digest, dctx->s); > - > - /* mac = (h + s) % (2^128) */ > - f = (f >> 32) + le32_to_cpu(digest[0]); > - put_unaligned_le32(f, dst); > - f = (f >> 32) + le32_to_cpu(digest[1]); > - put_unaligned_le32(f, dst + 4); > - f = (f >> 32) + le32_to_cpu(digest[2]); > - put_unaligned_le32(f, dst + 8); > - f = (f >> 32) + le32_to_cpu(digest[3]); > - put_unaligned_le32(f, dst + 12); > - > + poly1305_emit(&dctx->h, dst, dctx->s); > *dctx = (struct poly1305_desc_ctx){}; > } > EXPORT_SYMBOL(poly1305_final_arch); > diff --git a/arch/mips/crypto/poly1305-glue.c b/arch/mips/crypto/poly1305-glue.c > index b37d29cf5d0a..fc881b46d911 100644 > --- a/arch/mips/crypto/poly1305-glue.c > +++ b/arch/mips/crypto/poly1305-glue.c > @@ -15,7 +15,7 @@ > > asmlinkage void poly1305_init_mips(void *state, const u8 *key); > asmlinkage void poly1305_blocks_mips(void *state, const u8 *src, u32 len, u32 hibit); > -asmlinkage void poly1305_emit_mips(void *state, __le32 *digest, const u32 *nonce); > +asmlinkage void poly1305_emit_mips(void *state, u8 *digest, const u32 *nonce); > > void poly1305_init_arch(struct poly1305_desc_ctx *dctx, const u8 *key) > { > @@ -134,9 +134,6 @@ EXPORT_SYMBOL(poly1305_update_arch); > > void poly1305_final_arch(struct poly1305_desc_ctx *dctx, u8 *dst) > { > - __le32 digest[4]; > - u64 f = 0; > - > if (unlikely(dctx->buflen)) { > dctx->buf[dctx->buflen++] = 1; > memset(dctx->buf + dctx->buflen, 0, > @@ -144,18 +141,7 @@ void poly1305_final_arch(struct poly1305_desc_ctx *dctx, u8 *dst) > poly1305_blocks_mips(&dctx->h, dctx->buf, POLY1305_BLOCK_SIZE, 0); > } > > - poly1305_emit_mips(&dctx->h, digest, dctx->s); > - > - /* mac = (h + s) % (2^128) */ > - f = (f >> 32) + le32_to_cpu(digest[0]); > - put_unaligned_le32(f, dst); > - f = (f >> 32) + le32_to_cpu(digest[1]); > - put_unaligned_le32(f, dst + 4); > - f = (f >> 32) + le32_to_cpu(digest[2]); > - put_unaligned_le32(f, dst + 8); > - f = (f >> 32) + le32_to_cpu(digest[3]); > - put_unaligned_le32(f, dst + 12); > - > + poly1305_emit_mips(&dctx->h, dst, dctx->s); > *dctx = (struct poly1305_desc_ctx){}; > } > EXPORT_SYMBOL(poly1305_final_arch); > -- > 2.24.0 >
diff --git a/arch/arm/crypto/poly1305-glue.c b/arch/arm/crypto/poly1305-glue.c index abe3f2d587dc..ceec04ec2f40 100644 --- a/arch/arm/crypto/poly1305-glue.c +++ b/arch/arm/crypto/poly1305-glue.c @@ -20,7 +20,7 @@ void poly1305_init_arm(void *state, const u8 *key); void poly1305_blocks_arm(void *state, const u8 *src, u32 len, u32 hibit); -void poly1305_emit_arm(void *state, __le32 *digest, const u32 *nonce); +void poly1305_emit_arm(void *state, u8 *digest, const u32 *nonce); void __weak poly1305_blocks_neon(void *state, const u8 *src, u32 len, u32 hibit) { @@ -179,9 +179,6 @@ EXPORT_SYMBOL(poly1305_update_arch); void poly1305_final_arch(struct poly1305_desc_ctx *dctx, u8 *dst) { - __le32 digest[4]; - u64 f = 0; - if (unlikely(dctx->buflen)) { dctx->buf[dctx->buflen++] = 1; memset(dctx->buf + dctx->buflen, 0, @@ -189,18 +186,7 @@ void poly1305_final_arch(struct poly1305_desc_ctx *dctx, u8 *dst) poly1305_blocks_arm(&dctx->h, dctx->buf, POLY1305_BLOCK_SIZE, 0); } - poly1305_emit_arm(&dctx->h, digest, dctx->s); - - /* mac = (h + s) % (2^128) */ - f = (f >> 32) + le32_to_cpu(digest[0]); - put_unaligned_le32(f, dst); - f = (f >> 32) + le32_to_cpu(digest[1]); - put_unaligned_le32(f, dst + 4); - f = (f >> 32) + le32_to_cpu(digest[2]); - put_unaligned_le32(f, dst + 8); - f = (f >> 32) + le32_to_cpu(digest[3]); - put_unaligned_le32(f, dst + 12); - + poly1305_emit_arm(&dctx->h, dst, dctx->s); *dctx = (struct poly1305_desc_ctx){}; } EXPORT_SYMBOL(poly1305_final_arch); diff --git a/arch/arm64/crypto/poly1305-glue.c b/arch/arm64/crypto/poly1305-glue.c index 83a2338a8826..e97b092f56b8 100644 --- a/arch/arm64/crypto/poly1305-glue.c +++ b/arch/arm64/crypto/poly1305-glue.c @@ -21,7 +21,7 @@ asmlinkage void poly1305_init_arm64(void *state, const u8 *key); asmlinkage void poly1305_blocks(void *state, const u8 *src, u32 len, u32 hibit); asmlinkage void poly1305_blocks_neon(void *state, const u8 *src, u32 len, u32 hibit); -asmlinkage void poly1305_emit(void *state, __le32 *digest, const u32 *nonce); +asmlinkage void poly1305_emit(void *state, u8 *digest, const u32 *nonce); static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_neon); @@ -162,9 +162,6 @@ EXPORT_SYMBOL(poly1305_update_arch); void poly1305_final_arch(struct poly1305_desc_ctx *dctx, u8 *dst) { - __le32 digest[4]; - u64 f = 0; - if (unlikely(dctx->buflen)) { dctx->buf[dctx->buflen++] = 1; memset(dctx->buf + dctx->buflen, 0, @@ -172,18 +169,7 @@ void poly1305_final_arch(struct poly1305_desc_ctx *dctx, u8 *dst) poly1305_blocks(&dctx->h, dctx->buf, POLY1305_BLOCK_SIZE, 0); } - poly1305_emit(&dctx->h, digest, dctx->s); - - /* mac = (h + s) % (2^128) */ - f = (f >> 32) + le32_to_cpu(digest[0]); - put_unaligned_le32(f, dst); - f = (f >> 32) + le32_to_cpu(digest[1]); - put_unaligned_le32(f, dst + 4); - f = (f >> 32) + le32_to_cpu(digest[2]); - put_unaligned_le32(f, dst + 8); - f = (f >> 32) + le32_to_cpu(digest[3]); - put_unaligned_le32(f, dst + 12); - + poly1305_emit(&dctx->h, dst, dctx->s); *dctx = (struct poly1305_desc_ctx){}; } EXPORT_SYMBOL(poly1305_final_arch); diff --git a/arch/mips/crypto/poly1305-glue.c b/arch/mips/crypto/poly1305-glue.c index b37d29cf5d0a..fc881b46d911 100644 --- a/arch/mips/crypto/poly1305-glue.c +++ b/arch/mips/crypto/poly1305-glue.c @@ -15,7 +15,7 @@ asmlinkage void poly1305_init_mips(void *state, const u8 *key); asmlinkage void poly1305_blocks_mips(void *state, const u8 *src, u32 len, u32 hibit); -asmlinkage void poly1305_emit_mips(void *state, __le32 *digest, const u32 *nonce); +asmlinkage void poly1305_emit_mips(void *state, u8 *digest, const u32 *nonce); void poly1305_init_arch(struct poly1305_desc_ctx *dctx, const u8 *key) { @@ -134,9 +134,6 @@ EXPORT_SYMBOL(poly1305_update_arch); void poly1305_final_arch(struct poly1305_desc_ctx *dctx, u8 *dst) { - __le32 digest[4]; - u64 f = 0; - if (unlikely(dctx->buflen)) { dctx->buf[dctx->buflen++] = 1; memset(dctx->buf + dctx->buflen, 0, @@ -144,18 +141,7 @@ void poly1305_final_arch(struct poly1305_desc_ctx *dctx, u8 *dst) poly1305_blocks_mips(&dctx->h, dctx->buf, POLY1305_BLOCK_SIZE, 0); } - poly1305_emit_mips(&dctx->h, digest, dctx->s); - - /* mac = (h + s) % (2^128) */ - f = (f >> 32) + le32_to_cpu(digest[0]); - put_unaligned_le32(f, dst); - f = (f >> 32) + le32_to_cpu(digest[1]); - put_unaligned_le32(f, dst + 4); - f = (f >> 32) + le32_to_cpu(digest[2]); - put_unaligned_le32(f, dst + 8); - f = (f >> 32) + le32_to_cpu(digest[3]); - put_unaligned_le32(f, dst + 12); - + poly1305_emit_mips(&dctx->h, dst, dctx->s); *dctx = (struct poly1305_desc_ctx){}; } EXPORT_SYMBOL(poly1305_final_arch);
This appears to be some kind of copy and paste error, and is actually dead code. Pre: f = 0 ⇒ (f >> 32) = 0 f = (f >> 32) + le32_to_cpu(digest[0]); Post: 0 ≤ f < 2³² put_unaligned_le32(f, dst); Pre: 0 ≤ f < 2³² ⇒ (f >> 32) = 0 f = (f >> 32) + le32_to_cpu(digest[1]); Post: 0 ≤ f < 2³² put_unaligned_le32(f, dst + 4); Pre: 0 ≤ f < 2³² ⇒ (f >> 32) = 0 f = (f >> 32) + le32_to_cpu(digest[2]); Post: 0 ≤ f < 2³² put_unaligned_le32(f, dst + 8); Pre: 0 ≤ f < 2³² ⇒ (f >> 32) = 0 f = (f >> 32) + le32_to_cpu(digest[3]); Post: 0 ≤ f < 2³² put_unaligned_le32(f, dst + 12); Therefore this sequence is redundant. And Andy's code appears to handle misalignment acceptably. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> --- arch/arm/crypto/poly1305-glue.c | 18 ++---------------- arch/arm64/crypto/poly1305-glue.c | 18 ++---------------- arch/mips/crypto/poly1305-glue.c | 18 ++---------------- 3 files changed, 6 insertions(+), 48 deletions(-) -- 2.24.0