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generic-gmac: convert to the new common method helpers

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This commit is contained in:
Matthias Schiffer 2013-11-30 07:46:01 +01:00
parent bba8249f4a
commit eb891d772d
1 changed files with 19 additions and 33 deletions
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52
src/methods/generic_gmac/generic_gmac.c
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@ -139,8 +139,7 @@ static inline void put_size(fastd_block128_t *out, size_t len) {
}
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));
fastd_buffer_pull_head_zero(ctx, &in, 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_HEADBYTES, 16), sizeof(fastd_block128_t)+tail_len);
@ -148,17 +147,14 @@ 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);
size_t iv_length = session->method->cipher_info->iv_length;
uint8_t nonce[iv_length];
memset(nonce, 0, iv_length);
memcpy(nonce, session->common.send_nonce, COMMON_NONCEBYTES);
nonce[iv_length-1] = 1;
uint8_t nonce[session->method->cipher_info->iv_length];
fastd_method_expand_nonce(nonce, session->common.send_nonce, sizeof(nonce));
int n_blocks = block_count(in.len, sizeof(fastd_block128_t));
fastd_block128_t *inblocks = in.data;
fastd_block128_t *outblocks = out->data;
fastd_block128_t sig;
fastd_block128_t tag;
bool ok = session->cipher->crypt(session->cipher_state, outblocks, inblocks, n_blocks*sizeof(fastd_block128_t), nonce);
@ -168,27 +164,21 @@ static bool method_encrypt(fastd_context_t *ctx, fastd_peer_t *peer UNUSED, fast
put_size(&outblocks[n_blocks], in.len-sizeof(fastd_block128_t));
ok = session->ghash->hash(session->ghash_state, &sig, outblocks+1, n_blocks);
ok = session->ghash->hash(session->ghash_state, &tag, 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);
xor_a(&outblocks[0], tag);
fastd_buffer_free(in);
fastd_buffer_pull_head(ctx, out, COMMON_HEADBYTES);
memcpy(out->data, session->common.send_nonce, COMMON_NONCEBYTES);
fastd_method_put_common_header(ctx, out, session->common.send_nonce, 0);
fastd_method_increment_nonce(&session->common);
((uint8_t*)out->data)[COMMON_NONCEBYTES] = 0; /* flags */
return true;
}
@ -199,21 +189,17 @@ static bool method_decrypt(fastd_context_t *ctx, fastd_peer_t *peer, fastd_metho
if (!method_session_is_valid(ctx, session))
return false;
if (((const uint8_t*)in.data)[COMMON_NONCEBYTES]) /* flags */
return false;
size_t iv_length = session->method->cipher_info->iv_length;
uint8_t nonce[iv_length];
memset(nonce, 0, iv_length);
memcpy(nonce, in.data, COMMON_NONCEBYTES);
nonce[iv_length-1] = 1;
uint8_t in_nonce[COMMON_NONCEBYTES];
uint8_t flags;
int64_t age;
if (!fastd_method_is_nonce_valid(ctx, &session->common, nonce, &age))
if (!fastd_method_handle_common_header(ctx, &session->common, &in, in_nonce, &flags, &age))
return false;
fastd_buffer_push_head(ctx, &in, COMMON_HEADBYTES);
if (flags)
return false;
uint8_t nonce[session->method->cipher_info->iv_length];
fastd_method_expand_nonce(nonce, in_nonce, sizeof(nonce));
size_t tail_len = alignto(in.len, sizeof(fastd_block128_t))-in.len;
*out = fastd_buffer_alloc(ctx, in.len, 0, tail_len);
@ -222,7 +208,7 @@ static bool method_decrypt(fastd_context_t *ctx, fastd_peer_t *peer, fastd_metho
fastd_block128_t *inblocks = in.data;
fastd_block128_t *outblocks = out->data;
fastd_block128_t sig;
fastd_block128_t tag;
bool ok = session->cipher->crypt(session->cipher_state, outblocks, inblocks, n_blocks*sizeof(fastd_block128_t), nonce);
@ -232,10 +218,10 @@ static bool method_decrypt(fastd_context_t *ctx, fastd_peer_t *peer, fastd_metho
put_size(&inblocks[n_blocks], in.len-sizeof(fastd_block128_t));
ok = session->ghash->hash(session->ghash_state, &sig, inblocks+1, n_blocks);
ok = session->ghash->hash(session->ghash_state, &tag, inblocks+1, n_blocks);
}
if (!ok || memcmp(&sig, &outblocks[0], sizeof(fastd_block128_t)) != 0) {
if (!ok || memcmp(&tag, &outblocks[0], sizeof(fastd_block128_t)) != 0) {
fastd_buffer_free(*out);
return false;
}
@ -244,7 +230,7 @@ static bool method_decrypt(fastd_context_t *ctx, fastd_peer_t *peer, fastd_metho
fastd_buffer_push_head(ctx, out, sizeof(fastd_block128_t));
if (!fastd_method_reorder_check(ctx, peer, &session->common, nonce, age)) {
if (!fastd_method_reorder_check(ctx, peer, &session->common, in_nonce, age)) {
fastd_buffer_free(*out);
*out = fastd_buffer_alloc(ctx, 0, 0, 0);
}