diff options
Diffstat (limited to 'src/methods/aes128_gcm/aes128_gcm.c')
| -rw-r--r-- | src/methods/aes128_gcm/aes128_gcm.c | 261 |
1 files changed, 0 insertions, 261 deletions
diff --git a/src/methods/aes128_gcm/aes128_gcm.c b/src/methods/aes128_gcm/aes128_gcm.c deleted file mode 100644 index 8a6325e..0000000 --- a/src/methods/aes128_gcm/aes128_gcm.c +++ /dev/null @@ -1,261 +0,0 @@ -/* - Copyright (c) 2012-2013, Matthias Schiffer <mschiffer@universe-factory.net> - 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" -#include "../common.h" - - -struct fastd_method_session_state { - fastd_method_common_t common; - - const fastd_cipher_t *aes128_ctr; - fastd_cipher_context_t *aes128_ctr_ctx; - fastd_cipher_state_t *aes128_ctr_state; - - fastd_crypto_ghash_state_t *cstate_ghash; -}; - - -static bool method_provides(fastd_context_t *ctx UNUSED, const char *name) { - return !strcmp(name, "aes128-gcm"); -} - -static size_t method_max_packet_size(fastd_context_t *ctx) { - return (fastd_max_packet_size(ctx) + COMMON_NONCEBYTES + sizeof(fastd_block128_t)); -} - - -static size_t method_min_encrypt_head_space(fastd_context_t *ctx UNUSED) { - return sizeof(fastd_block128_t); -} - -static size_t method_min_decrypt_head_space(fastd_context_t *ctx UNUSED) { - return 0; -} - -static size_t method_min_encrypt_tail_space(fastd_context_t *ctx UNUSED) { - return (sizeof(fastd_block128_t)-1); -} - -static size_t method_min_decrypt_tail_space(fastd_context_t *ctx UNUSED) { - return (2*sizeof(fastd_block128_t)-1); -} - - -static size_t method_key_length(fastd_context_t *ctx UNUSED) { - return sizeof(fastd_block128_t); -} - -static fastd_method_session_state_t* method_session_init(fastd_context_t *ctx, const char *name UNUSED, const uint8_t *secret, bool initiator) { - fastd_method_session_state_t *session = malloc(sizeof(fastd_method_session_state_t)); - - fastd_method_common_init(ctx, &session->common, initiator); - - session->aes128_ctr = fastd_cipher_get_by_name(ctx, "aes128-ctr", &session->aes128_ctr_ctx); - if (!session->aes128_ctr) - exit_bug(ctx, "aes128-gcm: can't instanciate aes128-ctr"); - - session->aes128_ctr_state = session->aes128_ctr->init_state(ctx, session->aes128_ctr_ctx, secret); - - static const fastd_block128_t zeroblock = {}; - fastd_block128_t H; - - session->aes128_ctr->crypt(ctx, session->aes128_ctr_state, &H, &zeroblock, sizeof(fastd_block128_t), &zeroblock); - - session->cstate_ghash = ctx->conf->crypto_ghash->set_h(ctx, ctx->crypto_ghash, &H); - - return session; -} - -static fastd_method_session_state_t* method_session_init_compat(fastd_context_t *ctx, const char *name, const uint8_t *secret, size_t length, bool initiator) { - if (length < sizeof(fastd_block128_t)) - exit_bug(ctx, "aes128-gcm: tried to init with short secret"); - - return method_session_init(ctx, name, secret, initiator); -} - -static bool method_session_is_valid(fastd_context_t *ctx, fastd_method_session_state_t *session) { - return (session && fastd_method_session_common_is_valid(ctx, &session->common)); -} - -static bool method_session_is_initiator(fastd_context_t *ctx UNUSED, fastd_method_session_state_t *session) { - return fastd_method_session_common_is_initiator(&session->common); -} - -static bool method_session_want_refresh(fastd_context_t *ctx, fastd_method_session_state_t *session) { - return fastd_method_session_common_want_refresh(ctx, &session->common); -} - -static void method_session_superseded(fastd_context_t *ctx, fastd_method_session_state_t *session) { - fastd_method_session_common_superseded(ctx, &session->common); -} - -static void method_session_free(fastd_context_t *ctx, fastd_method_session_state_t *session) { - if (session) { - session->aes128_ctr->free_state(ctx, session->aes128_ctr_state); - ctx->conf->crypto_ghash->free_state(ctx, session->cstate_ghash); - - secure_memzero(session, sizeof(fastd_method_session_state_t)); - free(session); - } -} - -static inline void put_size(fastd_block128_t *out, size_t len) { - memset(out, 0, sizeof(fastd_block128_t)-5); - out->b[sizeof(fastd_block128_t)-5] = len >> 29; - out->b[sizeof(fastd_block128_t)-4] = len >> 21; - out->b[sizeof(fastd_block128_t)-3] = len >> 13; - out->b[sizeof(fastd_block128_t)-2] = len >> 5; - out->b[sizeof(fastd_block128_t)-1] = len << 3; -} - -static bool method_encrypt(fastd_context_t *ctx, fastd_peer_t *peer UNUSED, fastd_method_session_state_t *session, fastd_buffer_t *out, fastd_buffer_t in) { - fastd_buffer_pull_head(ctx, &in, sizeof(fastd_block128_t)); - memset(in.data, 0, sizeof(fastd_block128_t)); - - size_t tail_len = alignto(in.len, sizeof(fastd_block128_t))-in.len; - *out = fastd_buffer_alloc(ctx, in.len, alignto(COMMON_NONCEBYTES, 16), sizeof(fastd_block128_t)+tail_len); - - if (tail_len) - memset(in.data+in.len, 0, tail_len); - - fastd_block128_t nonce; - memcpy(nonce.b, session->common.send_nonce, COMMON_NONCEBYTES); - memset(nonce.b+COMMON_NONCEBYTES, 0, sizeof(fastd_block128_t)-COMMON_NONCEBYTES-1); - nonce.b[sizeof(fastd_block128_t)-1] = 1; - - int n_blocks = (in.len+sizeof(fastd_block128_t)-1)/sizeof(fastd_block128_t); - - fastd_block128_t *inblocks = in.data; - fastd_block128_t *outblocks = out->data; - fastd_block128_t sig; - - bool ok = session->aes128_ctr->crypt(ctx, session->aes128_ctr_state, outblocks, inblocks, n_blocks*sizeof(fastd_block128_t), &nonce); - - if (ok) { - if (tail_len) - memset(out->data+out->len, 0, tail_len); - - put_size(&outblocks[n_blocks], in.len-sizeof(fastd_block128_t)); - - ok = ctx->conf->crypto_ghash->hash(ctx, session->cstate_ghash, &sig, outblocks+1, n_blocks); - } - - if (!ok) { - /* restore original buffer */ - fastd_buffer_push_head(ctx, &in, sizeof(fastd_block128_t)); - fastd_buffer_free(*out); - return false; - } - - xor_a(&outblocks[0], &sig); - - fastd_buffer_free(in); - - fastd_buffer_pull_head(ctx, out, COMMON_NONCEBYTES); - memcpy(out->data, session->common.send_nonce, COMMON_NONCEBYTES); - fastd_method_increment_nonce(&session->common); - - return true; -} - -static bool method_decrypt(fastd_context_t *ctx, fastd_peer_t *peer, fastd_method_session_state_t *session, fastd_buffer_t *out, fastd_buffer_t in) { - if (in.len < COMMON_NONCEBYTES+sizeof(fastd_block128_t)) - return false; - - if (!method_session_is_valid(ctx, session)) - return false; - - fastd_block128_t nonce; - memcpy(nonce.b, in.data, COMMON_NONCEBYTES); - memset(nonce.b+COMMON_NONCEBYTES, 0, sizeof(fastd_block128_t)-COMMON_NONCEBYTES-1); - nonce.b[sizeof(fastd_block128_t)-1] = 1; - - int64_t age; - if (!fastd_method_is_nonce_valid(ctx, &session->common, nonce.b, &age)) - return false; - - fastd_buffer_push_head(ctx, &in, COMMON_NONCEBYTES); - - size_t tail_len = alignto(in.len, sizeof(fastd_block128_t))-in.len; - *out = fastd_buffer_alloc(ctx, in.len, 0, tail_len); - - int n_blocks = (in.len+sizeof(fastd_block128_t)-1)/sizeof(fastd_block128_t); - - fastd_block128_t *inblocks = in.data; - fastd_block128_t *outblocks = out->data; - fastd_block128_t sig; - - bool ok = session->aes128_ctr->crypt(ctx, session->aes128_ctr_state, outblocks, inblocks, n_blocks*sizeof(fastd_block128_t), &nonce); - - if (ok) { - if (tail_len) - memset(in.data+in.len, 0, tail_len); - - put_size(&inblocks[n_blocks], in.len-sizeof(fastd_block128_t)); - - ok = ctx->conf->crypto_ghash->hash(ctx, session->cstate_ghash, &sig, inblocks+1, n_blocks); - } - - if (!ok || memcmp(&sig, &outblocks[0], sizeof(fastd_block128_t)) != 0) { - fastd_buffer_free(*out); - return false; - } - - fastd_buffer_free(in); - - fastd_buffer_push_head(ctx, out, sizeof(fastd_block128_t)); - - if (!fastd_method_reorder_check(ctx, peer, &session->common, nonce.b, age)) { - fastd_buffer_free(*out); - *out = fastd_buffer_alloc(ctx, 0, 0, 0); - } - - return true; -} - -const fastd_method_t fastd_method_aes128_gcm = { - .provides = method_provides, - - .max_packet_size = method_max_packet_size, - .min_encrypt_head_space = method_min_encrypt_head_space, - .min_decrypt_head_space = method_min_decrypt_head_space, - .min_encrypt_tail_space = method_min_encrypt_tail_space, - .min_decrypt_tail_space = method_min_decrypt_tail_space, - - .key_length = method_key_length, - .session_init = method_session_init, - .session_init_compat = method_session_init_compat, - .session_is_valid = method_session_is_valid, - .session_is_initiator = method_session_is_initiator, - .session_want_refresh = method_session_want_refresh, - .session_superseded = method_session_superseded, - .session_free = method_session_free, - - .encrypt = method_encrypt, - .decrypt = method_decrypt, -}; 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