From fcec3f6f9dc6b0643b98217f2764945a5d33840c Mon Sep 17 00:00:00 2001 From: David Gibson Date: Thu, 28 Sep 2023 11:20:58 +1000 Subject: siphash: Use more hygienic state initialiser The PREAMBLE macro sets up the SipHash initial internal state. It also defines that state as a variable, which isn't macro hygeinic. With previous changes simplifying this premable, it's now possible to replace it with a macro which simply expands to a C initialisedrfor that state. Signed-off-by: David Gibson Signed-off-by: Stefano Brivio --- siphash.c | 29 ++++++++++++----------------- 1 file changed, 12 insertions(+), 17 deletions(-) (limited to 'siphash.c') diff --git a/siphash.c b/siphash.c index 6932da2..21c560d 100644 --- a/siphash.c +++ b/siphash.c @@ -58,15 +58,12 @@ #define ROTL(x, b) (uint64_t)(((x) << (b)) | ((x) >> (64 - (b)))) -#define PREAMBLE \ - uint64_t v[4] = { 0x736f6d6570736575ULL, 0x646f72616e646f6dULL, \ - 0x6c7967656e657261ULL, 0x7465646279746573ULL }; \ - int __i; \ - \ - do { \ - for (__i = sizeof(v) / sizeof(v[0]) - 1; __i >= 0; __i--) \ - v[__i] ^= k[__i % 2]; \ - } while (0) +#define SIPHASH_INIT(k) { \ + 0x736f6d6570736575ULL ^ (k)[0], \ + 0x646f72616e646f6dULL ^ (k)[1], \ + 0x6c7967656e657261ULL ^ (k)[0], \ + 0x7465646279746573ULL ^ (k)[1] \ + } /** * sipround() - Perform rounds of SipHash scrambling @@ -140,7 +137,8 @@ __attribute__((optimize("-fno-strict-aliasing"))) /* cppcheck-suppress unusedFunction */ uint64_t siphash_8b(const uint8_t *in, const uint64_t *k) { - PREAMBLE; + uint64_t v[4] = SIPHASH_INIT(k); + siphash_feed(v, *(uint64_t *)in); @@ -160,8 +158,8 @@ __attribute__((optimize("-fno-strict-aliasing"))) /* See siphash_8b() */ uint64_t siphash_12b(const uint8_t *in, const uint64_t *k) { uint32_t *in32 = (uint32_t *)in; + uint64_t v[4] = SIPHASH_INIT(k); - PREAMBLE; siphash_feed(v, (uint64_t)(*(in32 + 1)) << 32 | *in32); return siphash_final(v, 12, *(in32 + 2)); @@ -179,10 +177,9 @@ __attribute__((optimize("-fno-strict-aliasing"))) /* See siphash_8b() */ uint64_t siphash_20b(const uint8_t *in, const uint64_t *k) { uint32_t *in32 = (uint32_t *)in; + uint64_t v[4] = SIPHASH_INIT(k); int i; - PREAMBLE; - for (i = 0; i < 2; i++, in32 += 2) siphash_feed(v, (uint64_t)(*(in32 + 1)) << 32 | *in32); @@ -202,10 +199,9 @@ __attribute__((optimize("-fno-strict-aliasing"))) /* See siphash_8b() */ uint64_t siphash_32b(const uint8_t *in, const uint64_t *k) { uint64_t *in64 = (uint64_t *)in; + uint64_t v[4] = SIPHASH_INIT(k); int i; - PREAMBLE; - for (i = 0; i < 4; i++, in64++) siphash_feed(v, *in64); @@ -224,10 +220,9 @@ __attribute__((optimize("-fno-strict-aliasing"))) /* See siphash_8b() */ uint64_t siphash_36b(const uint8_t *in, const uint64_t *k) { uint32_t *in32 = (uint32_t *)in; + uint64_t v[4] = SIPHASH_INIT(k); int i; - PREAMBLE; - for (i = 0; i < 4; i++, in32 += 2) siphash_feed(v, (uint64_t)(*(in32 + 1)) << 32 | *in32); -- cgit v1.2.3