Signed-off-by: Richard Henderson <richard.hender...@linaro.org> --- include/crypto/clmul.h | 7 +++++++ crypto/clmul.c | 13 +++++++++++++ 2 files changed, 20 insertions(+)
diff --git a/include/crypto/clmul.h b/include/crypto/clmul.h index c7ad28aa85..0ea25a252c 100644 --- a/include/crypto/clmul.h +++ b/include/crypto/clmul.h @@ -54,4 +54,11 @@ uint64_t clmul_16x2_even(uint64_t, uint64_t); */ uint64_t clmul_16x2_odd(uint64_t, uint64_t); +/** + * clmul_32: + * + * Perform a 32x32->64 carry-less multiply. + */ +uint64_t clmul_32(uint32_t, uint32_t); + #endif /* CRYPTO_CLMUL_H */ diff --git a/crypto/clmul.c b/crypto/clmul.c index 2c87cfbf8a..36ada1be9d 100644 --- a/crypto/clmul.c +++ b/crypto/clmul.c @@ -79,3 +79,16 @@ uint64_t clmul_16x2_odd(uint64_t n, uint64_t m) { return clmul_16x2_even(n >> 16, m >> 16); } + +uint64_t clmul_32(uint32_t n, uint32_t m32) +{ + uint64_t r = 0; + uint64_t m = m32; + + for (int i = 0; i < 32; ++i) { + r ^= n & 1 ? m : 0; + n >>= 1; + m <<= 1; + } + return r; +} -- 2.34.1