From 2acd81bd7a1b364b02831ae5f8e46457d9d07865 Mon Sep 17 00:00:00 2001 From: Matthias Schiffer Date: Fri, 21 Sep 2012 15:07:11 +0200 Subject: Nicely encapsulate different crypto algorithm implementations --- src/crypto.c | 200 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 200 insertions(+) create mode 100644 src/crypto.c (limited to 'src/crypto.c') diff --git a/src/crypto.c b/src/crypto.c new file mode 100644 index 0000000..6aae261 --- /dev/null +++ b/src/crypto.c @@ -0,0 +1,200 @@ +/* + Copyright (c) 2012, 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" +#include "crypto.h" + + +#ifdef USE_CRYPTO_AES128CTR +#ifdef WITH_CRYPTO_AES128CTR_NACL + +#include + + +struct _fastd_crypto_aes128ctr_state { + fastd_buffer d; +}; + + +static fastd_crypto_aes128ctr_context* aes128ctr_init(fastd_context *ctx) { + return (fastd_crypto_aes128ctr_context*)1; +} + +static fastd_crypto_aes128ctr_state* aes128ctr_set_key(fastd_context *ctx, const fastd_crypto_aes128ctr_context *cctx, const fastd_block128 *key) { + fastd_crypto_aes128ctr_state *cstate = malloc(sizeof(fastd_crypto_aes128ctr_state)); + + cstate->d = fastd_buffer_alloc(crypto_stream_aes128ctr_BEFORENMBYTES, 0, 0); + crypto_stream_aes128ctr_beforenm(cstate->d.data, key->b); + + return cstate; +} + +static bool aes128ctr_crypt(fastd_context *ctx, const fastd_crypto_aes128ctr_state *cstate, fastd_block128 *out, const fastd_block128 *in, size_t len, const fastd_block128 *iv) { + crypto_stream_aes128ctr_xor_afternm(out->b, in->b, len, iv->b, cstate->d.data); + return true; +} + +static void aes128ctr_free_state(fastd_context *ctx, fastd_crypto_aes128ctr_state *cstate) { + if (cstate) { + fastd_buffer_free(cstate->d); + free(cstate); + } +} + +static void aes128ctr_free(fastd_context *ctx, fastd_crypto_aes128ctr_context *cctx) { +} + +fastd_crypto_aes128ctr fastd_crypto_aes128ctr_nacl = { + .name = "nacl", + + .init = aes128ctr_init, + .set_key = aes128ctr_set_key, + .crypt = aes128ctr_crypt, + + .free_state = aes128ctr_free_state, + .free = aes128ctr_free, +}; + +#endif +#endif + +#ifdef USE_CRYPTO_GHASH +#ifdef WITH_CRYPTO_GHASH_BUILTIN + +struct _fastd_crypto_ghash_state { + fastd_block128 H[32][16]; +}; + + +static const fastd_block128 r = { .b = {0xe1} }; + + +static inline uint8_t shr(fastd_block128 *out, const fastd_block128 *in, int n) { + int i; + uint8_t c = 0; + + for (i = 0; i < sizeof(fastd_block128); 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 *x, const fastd_crypto_ghash_state *cstate) { + fastd_block128 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_crypto_ghash_context* ghash_init(fastd_context *ctx) { + return (fastd_crypto_ghash_context*)1; +} + +static fastd_crypto_ghash_state* ghash_set_h(fastd_context *ctx, const fastd_crypto_ghash_context *cctx, const fastd_block128 *h) { + fastd_crypto_ghash_state *cstate = malloc(sizeof(fastd_crypto_ghash_state)); + + fastd_block128 Hbase[4]; + fastd_block128 Rbase[4]; + + Hbase[0] = *h; + 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 R[16]; + memset(cstate->H, 0, sizeof(cstate->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(&cstate->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(&cstate->H[i][j], &cstate->H[i-1][j], 4); + xor_a(&cstate->H[i][j], &R[carry]); + } + } + + return cstate; +} + +static bool ghash_hash(fastd_context *ctx, const fastd_crypto_ghash_state *cstate, fastd_block128 *out, const fastd_block128 *in, size_t n_blocks) { + memset(out, 0, sizeof(fastd_block128)); + + int i; + for (i = 0; i < n_blocks; i++) { + xor_a(out, &in[i]); + mulH_a(out, cstate); + } + + return true; +} + +static void ghash_free_state(fastd_context *ctx, fastd_crypto_ghash_state *cstate) { + free(cstate); +} + +static void ghash_free(fastd_context *ctx, fastd_crypto_ghash_context *cctx) { +} + +fastd_crypto_ghash fastd_crypto_ghash_builtin = { + .name = "builtin", + + .init = ghash_init, + .set_h = ghash_set_h, + .hash = ghash_hash, + + .free_state = ghash_free_state, + .free = ghash_free, +}; + +#endif +#endif -- cgit v1.2.3