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author | Richard Henderson <richard.henderson@linaro.org> | 2023-07-11 10:10:47 +0100 |
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committer | Richard Henderson <richard.henderson@linaro.org> | 2023-09-15 13:57:00 +0000 |
commit | 00f463b38aa7cfca0bc65e3af7f2c49e1b9da690 (patch) | |
tree | 1a0835b5c4babf3806eb4d3e373691b23efdd254 | |
parent | f56d3c1a140267ae88874d755fa2f24cb71a1572 (diff) | |
download | qemu-00f463b38aa7cfca0bc65e3af7f2c49e1b9da690.zip qemu-00f463b38aa7cfca0bc65e3af7f2c49e1b9da690.tar.gz qemu-00f463b38aa7cfca0bc65e3af7f2c49e1b9da690.tar.bz2 |
crypto: Add generic 64-bit carry-less multiply routine
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
-rw-r--r-- | crypto/clmul.c | 17 | ||||
-rw-r--r-- | host/include/generic/host/crypto/clmul.h | 15 | ||||
-rw-r--r-- | include/crypto/clmul.h | 19 |
3 files changed, 51 insertions, 0 deletions
diff --git a/crypto/clmul.c b/crypto/clmul.c index 36ada1b..9e3e61a 100644 --- a/crypto/clmul.c +++ b/crypto/clmul.c @@ -92,3 +92,20 @@ uint64_t clmul_32(uint32_t n, uint32_t m32) } return r; } + +Int128 clmul_64_gen(uint64_t n, uint64_t m) +{ + uint64_t rl = 0, rh = 0; + + /* Bit 0 can only influence the low 64-bit result. */ + if (n & 1) { + rl = m; + } + + for (int i = 1; i < 64; ++i) { + uint64_t mask = -((n >> i) & 1); + rl ^= (m << i) & mask; + rh ^= (m >> (64 - i)) & mask; + } + return int128_make128(rl, rh); +} diff --git a/host/include/generic/host/crypto/clmul.h b/host/include/generic/host/crypto/clmul.h new file mode 100644 index 0000000..915bfb8 --- /dev/null +++ b/host/include/generic/host/crypto/clmul.h @@ -0,0 +1,15 @@ +/* + * No host specific carry-less multiply acceleration. + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#ifndef GENERIC_HOST_CRYPTO_CLMUL_H +#define GENERIC_HOST_CRYPTO_CLMUL_H + +#define HAVE_CLMUL_ACCEL false +#define ATTR_CLMUL_ACCEL + +Int128 clmul_64_accel(uint64_t, uint64_t) + QEMU_ERROR("unsupported accel"); + +#endif /* GENERIC_HOST_CRYPTO_CLMUL_H */ diff --git a/include/crypto/clmul.h b/include/crypto/clmul.h index 80de516..446931f 100644 --- a/include/crypto/clmul.h +++ b/include/crypto/clmul.h @@ -8,6 +8,9 @@ #ifndef CRYPTO_CLMUL_H #define CRYPTO_CLMUL_H +#include "qemu/int128.h" +#include "host/crypto/clmul.h" + /** * clmul_8x8_low: * @@ -61,4 +64,20 @@ uint64_t clmul_16x2_odd(uint64_t, uint64_t); */ uint64_t clmul_32(uint32_t, uint32_t); +/** + * clmul_64: + * + * Perform a 64x64->128 carry-less multiply. + */ +Int128 clmul_64_gen(uint64_t, uint64_t); + +static inline Int128 clmul_64(uint64_t a, uint64_t b) +{ + if (HAVE_CLMUL_ACCEL) { + return clmul_64_accel(a, b); + } else { + return clmul_64_gen(a, b); + } +} + #endif /* CRYPTO_CLMUL_H */ |