1 files changed, 14 insertions, 33 deletions

diff --git a/src/methods/generic_gcm/generic_gcm.c b/src/methods/generic_gcm/generic_gcm.c
index 9c31ec4..a35a6c9 100644
--- a/src/methods/generic_gcm/generic_gcm.c
+++ b/src/methods/generic_gcm/generic_gcm.c
@@ -34,7 +34,6 @@ struct fastd_method_session_state {
 	const fastd_cipher_t *cipher;
 	const fastd_cipher_context_t *cipher_ctx;
 	fastd_cipher_state_t *cipher_state;
-	size_t ivlen;
 
 	const fastd_mac_t *ghash;
 	const fastd_mac_context_t *ghash_ctx;
@@ -77,30 +76,13 @@ static size_t method_max_packet_size(fastd_context_t *ctx) {
 }
 
 
-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, const char *name) {
 	const fastd_cipher_t *cipher = NULL;
 	const fastd_cipher_context_t *cctx;
 	if (!cipher_get(ctx, name, &cipher, &cctx))
 		exit_bug(ctx, "generic-gcm: can't get cipher key length");
 
-	return cipher->key_length(ctx, cctx);
+	return cipher->key_length;
 }
 
 static fastd_method_session_state_t* method_session_init(fastd_context_t *ctx, const char *name, const uint8_t *secret, bool initiator) {
@@ -116,12 +98,11 @@ static fastd_method_session_state_t* method_session_init(fastd_context_t *ctx, c
 	static const fastd_block128_t zeroblock = {};
 	fastd_block128_t H;
 
-	session->ivlen = session->cipher->iv_length(ctx, session->cipher_state);
-	if (session->ivlen <= COMMON_NONCEBYTES)
+	if (session->cipher->iv_length <= COMMON_NONCEBYTES)
 		exit_bug(ctx, "generic-gcm: iv_length to small");
 
-	uint8_t zeroiv[session->ivlen];
-	memset(zeroiv, 0, session->ivlen);
+	uint8_t zeroiv[session->cipher->iv_length];
+	memset(zeroiv, 0, session->cipher->iv_length);
 
 	session->cipher->crypt(ctx, session->cipher_state, &H, &zeroblock, sizeof(fastd_block128_t), zeroiv);
 
@@ -185,10 +166,10 @@ static bool method_encrypt(fastd_context_t *ctx, fastd_peer_t *peer UNUSED, fast
 	if (tail_len)
 		memset(in.data+in.len, 0, tail_len);
 
-	uint8_t nonce[session->ivlen];
-	memset(nonce, 0, session->ivlen);
+	uint8_t nonce[session->cipher->iv_length];
+	memset(nonce, 0, session->cipher->iv_length);
 	memcpy(nonce, session->common.send_nonce, COMMON_NONCEBYTES);
-	nonce[session->ivlen-1] = 1;
+	nonce[session->cipher->iv_length-1] = 1;
 
 	int n_blocks = block_count(in.len, sizeof(fastd_block128_t));
 
@@ -238,10 +219,10 @@ static bool method_decrypt(fastd_context_t *ctx, fastd_peer_t *peer, fastd_metho
 	if (((const uint8_t*)in.data)[COMMON_NONCEBYTES]) /* flags */
 		return false;
 
-	uint8_t nonce[session->ivlen];
-	memset(nonce, 0, session->ivlen);
+	uint8_t nonce[session->cipher->iv_length];
+	memset(nonce, 0, session->cipher->iv_length);
 	memcpy(nonce, in.data, COMMON_NONCEBYTES);
-	nonce[session->ivlen-1] = 1;
+	nonce[session->cipher->iv_length-1] = 1;
 
 	int64_t age;
 	if (!fastd_method_is_nonce_valid(ctx, &session->common, nonce, &age))
@@ -290,10 +271,10 @@ const fastd_method_t fastd_method_generic_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,
+	.min_encrypt_head_space = sizeof(fastd_block128_t),
+	.min_decrypt_head_space = 0,
+	.min_encrypt_tail_space = sizeof(fastd_block128_t)-1,
+	.min_decrypt_tail_space = 2*sizeof(fastd_block128_t)-1,
 
 	.key_length = method_key_length,
 	.session_init = method_session_init,