blob: 7e4e9c524d952adce6623c6d71d28828525784bd [file] [log] [blame]
/* Copyright (c) 2019, Google Inc.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
#include <stdint.h>
#include <string.h>
#include <openssl/siphash.h>
static void siphash_round(uint64_t v[4]) {
v[0] += v[1];
v[2] += v[3];
v[1] = (v[1] << 13) | (v[1] >> (64 - 13));
v[3] = (v[3] << 16) | (v[3] >> (64 - 16));
v[1] ^= v[0];
v[3] ^= v[2];
v[0] = (v[0] << 32) | (v[0] >> 32);
v[2] += v[1];
v[0] += v[3];
v[1] = (v[1] << 17) | (v[1] >> (64 - 17));
v[3] = (v[3] << 21) | (v[3] >> (64 - 21));
v[1] ^= v[2];
v[3] ^= v[0];
v[2] = (v[2] << 32) | (v[2] >> 32);
}
uint64_t SIPHASH_24(const uint64_t key[2], const uint8_t *input,
size_t input_len) {
const size_t orig_input_len = input_len;
uint64_t v[4];
v[0] = key[0] ^ UINT64_C(0x736f6d6570736575);
v[1] = key[1] ^ UINT64_C(0x646f72616e646f6d);
v[2] = key[0] ^ UINT64_C(0x6c7967656e657261);
v[3] = key[1] ^ UINT64_C(0x7465646279746573);
while (input_len >= sizeof(uint64_t)) {
uint64_t m;
memcpy(&m, input, sizeof(m));
v[3] ^= m;
siphash_round(v);
siphash_round(v);
v[0] ^= m;
input += sizeof(uint64_t);
input_len -= sizeof(uint64_t);
}
union {
uint8_t bytes[8];
uint64_t word;
} last_block;
last_block.word = 0;
memcpy(last_block.bytes, input, input_len);
last_block.bytes[7] = orig_input_len & 0xff;
v[3] ^= last_block.word;
siphash_round(v);
siphash_round(v);
v[0] ^= last_block.word;
v[2] ^= 0xff;
siphash_round(v);
siphash_round(v);
siphash_round(v);
siphash_round(v);
return v[0] ^ v[1] ^ v[2] ^ v[3];
}