From d4916544299c28c4fb16da6d3306eea0a6d5d79f Mon Sep 17 00:00:00 2001 From: Matthias Schiffer Date: Sat, 16 Nov 2013 21:52:20 +0100 Subject: Add "tiny" copy of the builtin ghash implementation --- src/crypto/mac/ghash/CMakeLists.txt | 1 + src/crypto/mac/ghash/tiny/CMakeLists.txt | 3 + src/crypto/mac/ghash/tiny/ghash_tiny.c | 147 +++++++++++++++++++++++++++++++ 3 files changed, 151 insertions(+) create mode 100644 src/crypto/mac/ghash/tiny/CMakeLists.txt create mode 100644 src/crypto/mac/ghash/tiny/ghash_tiny.c (limited to 'src/crypto') diff --git a/src/crypto/mac/ghash/CMakeLists.txt b/src/crypto/mac/ghash/CMakeLists.txt index 7d44b8a..481e77f 100644 --- a/src/crypto/mac/ghash/CMakeLists.txt +++ b/src/crypto/mac/ghash/CMakeLists.txt @@ -1,2 +1,3 @@ fastd_mac(ghash) add_subdirectory(builtin) +add_subdirectory(tiny) diff --git a/src/crypto/mac/ghash/tiny/CMakeLists.txt b/src/crypto/mac/ghash/tiny/CMakeLists.txt new file mode 100644 index 0000000..d16d098 --- /dev/null +++ b/src/crypto/mac/ghash/tiny/CMakeLists.txt @@ -0,0 +1,3 @@ +fastd_mac_impl(ghash tiny + ghash_tiny.c +) diff --git a/src/crypto/mac/ghash/tiny/ghash_tiny.c b/src/crypto/mac/ghash/tiny/ghash_tiny.c new file mode 100644 index 0000000..f4a06b0 --- /dev/null +++ b/src/crypto/mac/ghash/tiny/ghash_tiny.c @@ -0,0 +1,147 @@ +/* + Copyright (c) 2012-2013, Matthias Schiffer + All rights reserved. + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions are met: + + 1. Redistributions of source code must retain the above copyright notice, + this list of conditions and the following disclaimer. + 2. Redistributions in binary form must reproduce the above copyright notice, + this list of conditions and the following disclaimer in the documentation + and/or other materials provided with the distribution. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE + FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER + CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, + OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +*/ + + +#include "../../../../fastd.h" + + +struct fastd_mac_state { + fastd_block128_t H[32][16]; +}; + + +static const fastd_block128_t r = { .b = {0xe1} }; + + +static inline uint8_t shr(fastd_block128_t *out, const fastd_block128_t *in, int n) { + size_t i; + uint8_t c = 0; + + for (i = 0; i < sizeof(fastd_block128_t); i++) { + uint8_t c2 = in->b[i] << (8-n); + out->b[i] = (in->b[i] >> n) | c; + c = c2; + } + + return (c >> (8-n)); +} + +static inline void mulH_a(fastd_block128_t *x, const fastd_mac_state_t *cstate) { + fastd_block128_t out = {}; + + int i; + for (i = 0; i < 16; i++) { + xor_a(&out, &cstate->H[2*i][x->b[i]>>4]); + xor_a(&out, &cstate->H[2*i+1][x->b[i]&0xf]); + } + + *x = out; +} + + +static fastd_mac_context_t* ghash_initialize(fastd_context_t *ctx UNUSED) { + return NULL; +} + +static size_t ghash_key_length(fastd_context_t *ctx UNUSED, const fastd_mac_context_t *cctx UNUSED) { + return sizeof(fastd_block128_t); +} + +static fastd_mac_state_t* ghash_init_state(fastd_context_t *ctx UNUSED, const fastd_mac_context_t *mctx UNUSED, const uint8_t *key) { + fastd_mac_state_t *state = malloc(sizeof(fastd_mac_state_t)); + + fastd_block128_t Hbase[4]; + fastd_block128_t Rbase[4]; + + memcpy(&Hbase[0], key, sizeof(fastd_block128_t)); + Rbase[0] = r; + + int i; + for (i = 1; i < 4; i++) { + uint8_t carry = shr(&Hbase[i], &Hbase[i-1], 1); + if (carry) + xor_a(&Hbase[i], &r); + + shr(&Rbase[i], &Rbase[i-1], 1); + } + + fastd_block128_t R[16]; + memset(state->H, 0, sizeof(state->H)); + memset(R, 0, sizeof(R)); + + for (i = 0; i < 16; i++) { + int j; + for (j = 0; j < 4; j++) { + if (i & (8 >> j)) { + xor_a(&state->H[0][i], &Hbase[j]); + xor_a(&R[i], &Rbase[j]); + } + } + } + + for (i = 1; i < 32; i++) { + int j; + + for (j = 0; j < 16; j++) { + uint8_t carry = shr(&state->H[i][j], &state->H[i-1][j], 4); + xor_a(&state->H[i][j], &R[carry]); + } + } + + return state; +} + +static bool ghash_hash(fastd_context_t *ctx UNUSED, const fastd_mac_state_t *state, fastd_block128_t *out, const fastd_block128_t *in, size_t n_blocks) { + memset(out, 0, sizeof(fastd_block128_t)); + + size_t i; + for (i = 0; i < n_blocks; i++) { + xor_a(out, &in[i]); + mulH_a(out, state); + } + + return true; +} + +static void ghash_free_state(fastd_context_t *ctx UNUSED, fastd_mac_state_t *state) { + free(state); +} + +static void ghash_free(fastd_context_t *ctx UNUSED, fastd_mac_context_t *mctx UNUSED) { +} + +const fastd_mac_t fastd_mac_ghash_tiny = { + .name = "tiny", + + .initialize = ghash_initialize, + + .key_length = ghash_key_length, + .init_state = ghash_init_state, + + .hash = ghash_hash, + + .free_state = ghash_free_state, + .free = ghash_free, +}; -- cgit v1.2.3