Convert aes128-gcm into a generic gcm method

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,
-};