diff options
| author | Ard Biesheuvel <ardb@kernel.org> | 2023-07-31 10:40:43 +0200 |
|---|---|---|
| committer | Alistair Francis <alistair.francis@wdc.com> | 2023-09-11 11:45:54 +1000 |
| commit | 9ea17007c4ae4420ccd917eb300c7db49483a5b8 (patch) | |
| tree | 9c207d8afbb2d7e1936b02f29b692b78d65defd6 /crypto/aes.c | |
| parent | 4cc9f284d5971ecd8055d26ef74c23ef0be8b8f5 (diff) | |
target/riscv: Use existing lookup tables for MixColumns
The AES MixColumns and InvMixColumns operations are relatively
expensive 4x4 matrix multiplications in GF(2^8), which is why C
implementations usually rely on precomputed lookup tables rather than
performing the calculations on demand.
Given that we already carry those tables in QEMU, we can just grab the
right value in the implementation of the RISC-V AES32 instructions. Note
that the tables in question are permuted according to the respective
Sbox, so we can omit the Sbox lookup as well in this case.
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Philippe Mathieu-Daudé <philmd@linaro.org>
Cc: Zewen Ye <lustrew@foxmail.com>
Cc: Weiwei Li <liweiwei@iscas.ac.cn>
Cc: Junqiang Wang <wangjunqiang@iscas.ac.cn>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20230731084043.1791984-1-ardb@kernel.org>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Diffstat (limited to 'crypto/aes.c')
| -rw-r--r-- | crypto/aes.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/crypto/aes.c b/crypto/aes.c index 836d7d5c0b..df4362ac60 100644 --- a/crypto/aes.c +++ b/crypto/aes.c @@ -272,7 +272,7 @@ AES_Td3[x] = Si[x].[09, 0d, 0b, 0e]; AES_Td4[x] = Si[x].[01, 01, 01, 01]; */ -static const uint32_t AES_Te0[256] = { +const uint32_t AES_Te0[256] = { 0xc66363a5U, 0xf87c7c84U, 0xee777799U, 0xf67b7b8dU, 0xfff2f20dU, 0xd66b6bbdU, 0xde6f6fb1U, 0x91c5c554U, 0x60303050U, 0x02010103U, 0xce6767a9U, 0x562b2b7dU, @@ -607,7 +607,7 @@ static const uint32_t AES_Te4[256] = { 0xb0b0b0b0U, 0x54545454U, 0xbbbbbbbbU, 0x16161616U, }; -static const uint32_t AES_Td0[256] = { +const uint32_t AES_Td0[256] = { 0x51f4a750U, 0x7e416553U, 0x1a17a4c3U, 0x3a275e96U, 0x3bab6bcbU, 0x1f9d45f1U, 0xacfa58abU, 0x4be30393U, 0x2030fa55U, 0xad766df6U, 0x88cc7691U, 0xf5024c25U, |