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path: root/arch/arm/crypto/aes-cipher-core.S
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* crypto: arm/aes-cipher - move S-box to .rodata sectionJinbum Park2018-02-22
| | | | | | | | | Move the AES inverse S-box to the .rodata section where it is safe from abuse by speculation. Signed-off-by: Jinbum Park <jinb.park7@gmail.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: arm/aes - avoid expanded lookup tables in the final roundArd Biesheuvel2017-08-04
| | | | | | | | | | | | | | | | | For the final round, avoid the expanded and padded lookup tables exported by the generic AES driver. Instead, for encryption, we can perform byte loads from the same table we used for the inner rounds, which will still be hot in the caches. For decryption, use the inverse AES Sbox directly, which is 4x smaller than the inverse lookup table exported by the generic driver. This should significantly reduce the Dcache footprint of our code, which makes the code more robust against timing attacks. It does not introduce any additional module dependencies, given that we already rely on the core AES module for the shared key expansion routines. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: arm/aes - avoid reserved 'tt' mnemonic in asm codeArd Biesheuvel2017-01-13
| | | | | | | | | | The ARMv8-M architecture introduces 'tt' and 'ttt' instructions, which means we can no longer use 'tt' as a register alias on recent versions of binutils for ARM. So replace the alias with 'ttab'. Fixes: 81edb4262975 ("crypto: arm/aes - replace scalar AES cipher") Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: arm/aes - replace scalar AES cipherArd Biesheuvel2017-01-13
This replaces the scalar AES cipher that originates in the OpenSSL project with a new implementation that is ~15% (*) faster (on modern cores), and reuses the lookup tables and the key schedule generation routines from the generic C implementation (which is usually compiled in anyway due to networking and other subsystems depending on it). Note that the bit sliced NEON code for AES still depends on the scalar cipher that this patch replaces, so it is not removed entirely yet. * On Cortex-A57, the performance increases from 17.0 to 14.9 cycles per byte for 128-bit keys. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>