openssl/crypto/siphash/siphash.c
Richard Levitte d74f23d2db SipHash: add separate setter for the hash size
This was originally part of SipHash_Init.  However, there are cases
where there isn't any key material to initialize from when setting the
hash size, and we do allow doing so with a EVP_PKEY control.  The
solution is to provide a separate hash_size setter and to use it in
the corresponding EVP_PKEY_METHOD.

Fixes #7143

Reviewed-by: Tim Hudson <tjh@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/7145)
2018-09-09 01:47:56 +02:00

248 lines
7.5 KiB
C

/*
* Copyright 2017 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
/* Based on https://131002.net/siphash C reference implementation */
/*
SipHash reference C implementation
Copyright (c) 2012-2016 Jean-Philippe Aumasson
Copyright (c) 2012-2014 Daniel J. Bernstein
To the extent possible under law, the author(s) have dedicated all copyright
and related and neighboring rights to this software to the public domain
worldwide. This software is distributed without any warranty.
You should have received a copy of the CC0 Public Domain Dedication along
with this software. If not, see
<http://creativecommons.org/publicdomain/zero/1.0/>.
*/
#include <stdlib.h>
#include <string.h>
#include <openssl/crypto.h>
#include "internal/siphash.h"
#include "siphash_local.h"
/* default: SipHash-2-4 */
#define SIPHASH_C_ROUNDS 2
#define SIPHASH_D_ROUNDS 4
#define ROTL(x, b) (uint64_t)(((x) << (b)) | ((x) >> (64 - (b))))
#define U32TO8_LE(p, v) \
(p)[0] = (uint8_t)((v)); \
(p)[1] = (uint8_t)((v) >> 8); \
(p)[2] = (uint8_t)((v) >> 16); \
(p)[3] = (uint8_t)((v) >> 24);
#define U64TO8_LE(p, v) \
U32TO8_LE((p), (uint32_t)((v))); \
U32TO8_LE((p) + 4, (uint32_t)((v) >> 32));
#define U8TO64_LE(p) \
(((uint64_t)((p)[0])) | ((uint64_t)((p)[1]) << 8) | \
((uint64_t)((p)[2]) << 16) | ((uint64_t)((p)[3]) << 24) | \
((uint64_t)((p)[4]) << 32) | ((uint64_t)((p)[5]) << 40) | \
((uint64_t)((p)[6]) << 48) | ((uint64_t)((p)[7]) << 56))
#define SIPROUND \
do { \
v0 += v1; \
v1 = ROTL(v1, 13); \
v1 ^= v0; \
v0 = ROTL(v0, 32); \
v2 += v3; \
v3 = ROTL(v3, 16); \
v3 ^= v2; \
v0 += v3; \
v3 = ROTL(v3, 21); \
v3 ^= v0; \
v2 += v1; \
v1 = ROTL(v1, 17); \
v1 ^= v2; \
v2 = ROTL(v2, 32); \
} while (0)
size_t SipHash_ctx_size(void)
{
return sizeof(SIPHASH);
}
size_t SipHash_hash_size(SIPHASH *ctx)
{
return ctx->hash_size;
}
static size_t siphash_adjust_hash_size(size_t hash_size)
{
if (hash_size == 0)
hash_size = SIPHASH_MAX_DIGEST_SIZE;
return hash_size;
}
int SipHash_set_hash_size(SIPHASH *ctx, size_t hash_size)
{
hash_size = siphash_adjust_hash_size(hash_size);
if (hash_size != SIPHASH_MIN_DIGEST_SIZE
&& hash_size != SIPHASH_MAX_DIGEST_SIZE)
return 0;
ctx->hash_size = hash_size;
return 1;
}
/* hash_size = crounds = drounds = 0 means SipHash24 with 16-byte output */
int SipHash_Init(SIPHASH *ctx, const unsigned char *k, int crounds, int drounds)
{
uint64_t k0 = U8TO64_LE(k);
uint64_t k1 = U8TO64_LE(k + 8);
/* If the hash size wasn't set, i.e. is zero */
ctx->hash_size = siphash_adjust_hash_size(ctx->hash_size);
if (drounds == 0)
drounds = SIPHASH_D_ROUNDS;
if (crounds == 0)
crounds = SIPHASH_C_ROUNDS;
ctx->crounds = crounds;
ctx->drounds = drounds;
ctx->len = 0;
ctx->total_inlen = 0;
ctx->v0 = 0x736f6d6570736575ULL ^ k0;
ctx->v1 = 0x646f72616e646f6dULL ^ k1;
ctx->v2 = 0x6c7967656e657261ULL ^ k0;
ctx->v3 = 0x7465646279746573ULL ^ k1;
if (ctx->hash_size == SIPHASH_MAX_DIGEST_SIZE)
ctx->v1 ^= 0xee;
return 1;
}
void SipHash_Update(SIPHASH *ctx, const unsigned char *in, size_t inlen)
{
uint64_t m;
const uint8_t *end;
int left;
int i;
uint64_t v0 = ctx->v0;
uint64_t v1 = ctx->v1;
uint64_t v2 = ctx->v2;
uint64_t v3 = ctx->v3;
ctx->total_inlen += inlen;
if (ctx->len) {
/* deal with leavings */
size_t available = SIPHASH_BLOCK_SIZE - ctx->len;
/* not enough to fill leavings */
if (inlen < available) {
memcpy(&ctx->leavings[ctx->len], in, inlen);
ctx->len += inlen;
return;
}
/* copy data into leavings and reduce input */
memcpy(&ctx->leavings[ctx->len], in, available);
inlen -= available;
in += available;
/* process leavings */
m = U8TO64_LE(ctx->leavings);
v3 ^= m;
for (i = 0; i < ctx->crounds; ++i)
SIPROUND;
v0 ^= m;
}
left = inlen & (SIPHASH_BLOCK_SIZE-1); /* gets put into leavings */
end = in + inlen - left;
for (; in != end; in += 8) {
m = U8TO64_LE(in);
v3 ^= m;
for (i = 0; i < ctx->crounds; ++i)
SIPROUND;
v0 ^= m;
}
/* save leavings and other ctx */
if (left)
memcpy(ctx->leavings, end, left);
ctx->len = left;
ctx->v0 = v0;
ctx->v1 = v1;
ctx->v2 = v2;
ctx->v3 = v3;
}
int SipHash_Final(SIPHASH *ctx, unsigned char *out, size_t outlen)
{
/* finalize hash */
int i;
uint64_t b = ctx->total_inlen << 56;
uint64_t v0 = ctx->v0;
uint64_t v1 = ctx->v1;
uint64_t v2 = ctx->v2;
uint64_t v3 = ctx->v3;
if (outlen != (size_t)ctx->hash_size)
return 0;
switch (ctx->len) {
case 7:
b |= ((uint64_t)ctx->leavings[6]) << 48;
/* fall thru */
case 6:
b |= ((uint64_t)ctx->leavings[5]) << 40;
/* fall thru */
case 5:
b |= ((uint64_t)ctx->leavings[4]) << 32;
/* fall thru */
case 4:
b |= ((uint64_t)ctx->leavings[3]) << 24;
/* fall thru */
case 3:
b |= ((uint64_t)ctx->leavings[2]) << 16;
/* fall thru */
case 2:
b |= ((uint64_t)ctx->leavings[1]) << 8;
/* fall thru */
case 1:
b |= ((uint64_t)ctx->leavings[0]);
case 0:
break;
}
v3 ^= b;
for (i = 0; i < ctx->crounds; ++i)
SIPROUND;
v0 ^= b;
if (ctx->hash_size == SIPHASH_MAX_DIGEST_SIZE)
v2 ^= 0xee;
else
v2 ^= 0xff;
for (i = 0; i < ctx->drounds; ++i)
SIPROUND;
b = v0 ^ v1 ^ v2 ^ v3;
U64TO8_LE(out, b);
if (ctx->hash_size == SIPHASH_MIN_DIGEST_SIZE)
return 1;
v1 ^= 0xdd;
for (i = 0; i < ctx->drounds; ++i)
SIPROUND;
b = v0 ^ v1 ^ v2 ^ v3;
U64TO8_LE(out + 8, b);
return 1;
}