diff --git a/src/openvpn/siphash.c b/src/openvpn/siphash.c new file mode 100644 index 000000000..b8a7bbc11 --- /dev/null +++ b/src/openvpn/siphash.c @@ -0,0 +1,212 @@ +/* + * SipHash reference C implementation + * + * Copyright (c) 2012-2022 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 + * . + */ + +#include "siphash.h" +#include +#include +#include + +/* default: SipHash-2-4 */ +#ifndef cROUNDS +#define cROUNDS 2 +#endif +#ifndef dROUNDS +#define dROUNDS 4 +#endif + +#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) + +#ifdef DEBUG_SIPHASH +#include + +#define TRACE \ + do { \ + printf("(%3zu) v0 %016" PRIx64 "\n", inlen, v0); \ + printf("(%3zu) v1 %016" PRIx64 "\n", inlen, v1); \ + printf("(%3zu) v2 %016" PRIx64 "\n", inlen, v2); \ + printf("(%3zu) v3 %016" PRIx64 "\n", inlen, v3); \ + } while (0) +#else /* ifdef DEBUG_SIPHASH */ +#define TRACE +#endif + +/* + * Computes a SipHash value + * in: pointer to input data (read-only) + * inlen: input data length in bytes (any size_t value) + * k: pointer to the key data (read-only), must be 16 bytes + * out: pointer to output data (write-only), outlen bytes must be allocated + * outlen: length of the output in bytes, must be 8 or 16 + */ +int +siphash(const void *in, const size_t inlen, const void *k, uint8_t *out, + const size_t outlen) +{ + + const unsigned char *ni = (const unsigned char *)in; + const unsigned char *kk = (const unsigned char *)k; + + assert((outlen == 8) || (outlen == 16)); + uint64_t v0 = UINT64_C(0x736f6d6570736575); + uint64_t v1 = UINT64_C(0x646f72616e646f6d); + uint64_t v2 = UINT64_C(0x6c7967656e657261); + uint64_t v3 = UINT64_C(0x7465646279746573); + uint64_t k0 = U8TO64_LE(kk); + uint64_t k1 = U8TO64_LE(kk + 8); + uint64_t m; + int i; + const unsigned char *end = ni + inlen - (inlen % sizeof(uint64_t)); + const int left = inlen & 7; + uint64_t b = ((uint64_t)inlen) << 56; + v3 ^= k1; + v2 ^= k0; + v1 ^= k1; + v0 ^= k0; + + if (outlen == 16) + { + v1 ^= 0xee; + } + + for (; ni != end; ni += 8) + { + m = U8TO64_LE(ni); + v3 ^= m; + + TRACE; + for (i = 0; i < cROUNDS; ++i) + { + SIPROUND; + } + + v0 ^= m; + } + + switch (left) + { + case 7: + b |= ((uint64_t)ni[6]) << 48; + + /* FALLTHRU */ + case 6: + b |= ((uint64_t)ni[5]) << 40; + + /* FALLTHRU */ + case 5: + b |= ((uint64_t)ni[4]) << 32; + + /* FALLTHRU */ + case 4: + b |= ((uint64_t)ni[3]) << 24; + + /* FALLTHRU */ + case 3: + b |= ((uint64_t)ni[2]) << 16; + + /* FALLTHRU */ + case 2: + b |= ((uint64_t)ni[1]) << 8; + + /* FALLTHRU */ + case 1: + b |= ((uint64_t)ni[0]); + break; + + case 0: + break; + } + + v3 ^= b; + + TRACE; + for (i = 0; i < cROUNDS; ++i) + { + SIPROUND; + } + + v0 ^= b; + + if (outlen == 16) + { + v2 ^= 0xee; + } + else + { + v2 ^= 0xff; + } + + TRACE; + for (i = 0; i < dROUNDS; ++i) + { + SIPROUND; + } + + b = v0 ^ v1 ^ v2 ^ v3; + U64TO8_LE(out, b); + + if (outlen == 8) + { + return 0; + } + + v1 ^= 0xdd; + + TRACE; + for (i = 0; i < dROUNDS; ++i) + { + SIPROUND; + } + + b = v0 ^ v1 ^ v2 ^ v3; + U64TO8_LE(out + 8, b); + + return 0; +} diff --git a/src/openvpn/siphash.h b/src/openvpn/siphash.h new file mode 100644 index 000000000..d26ee36ec --- /dev/null +++ b/src/openvpn/siphash.h @@ -0,0 +1,31 @@ +/* + * SipHash reference C implementation + * + * Copyright (c) 2012-2021 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 + * . + */ + +#ifndef SIPHASH_H +#define SIPHASH_H + +#include +#include + +int siphash(const void *in, size_t inlen, const void *k, uint8_t *out, + size_t outlen); + +/* siphash always uses 128-bit keys */ +#define SIPHASH_KEY_SIZE 16 +#define SIPHASH_HASH_SIZE 16 + +#endif