From c00e275e5b3e3630eee17a73c27380562e84736f Mon Sep 17 00:00:00 2001 From: Matthias Schiffer Date: Sat, 30 Nov 2013 07:53:23 +0100 Subject: composed-gmac: convert to the new common method helpers --- src/methods/composed_gmac/composed_gmac.c | 64 ++++++++++--------------------- 1 file changed, 21 insertions(+), 43 deletions(-) (limited to 'src/methods') diff --git a/src/methods/composed_gmac/composed_gmac.c b/src/methods/composed_gmac/composed_gmac.c index 87ce2e3..25805fa 100644 --- a/src/methods/composed_gmac/composed_gmac.c +++ b/src/methods/composed_gmac/composed_gmac.c @@ -187,24 +187,16 @@ static bool method_encrypt(fastd_context_t *ctx, fastd_peer_t *peer UNUSED, fast fastd_block128_t *inblocks = in.data; fastd_block128_t *outblocks = out->data; - fastd_block128_t sig; + fastd_block128_t tag; - size_t gmac_iv_length = session->method->gmac_cipher_info->iv_length; - uint8_t gmac_nonce[gmac_iv_length]; - memset(gmac_nonce, 0, gmac_iv_length); - memcpy(gmac_nonce, session->common.send_nonce, COMMON_NONCEBYTES); - gmac_nonce[gmac_iv_length-1] = 1; + uint8_t gmac_nonce[session->method->gmac_cipher_info->iv_length]; + fastd_method_expand_nonce(gmac_nonce, session->common.send_nonce, sizeof(gmac_nonce)); bool ok = session->gmac_cipher->crypt(session->gmac_cipher_state, outblocks, &ZERO_BLOCK, sizeof(fastd_block128_t), gmac_nonce); if (ok) { - size_t iv_length = session->method->cipher_info->iv_length; - uint8_t nonce[iv_length]; - if (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)); ok = session->cipher->crypt(session->cipher_state, outblocks+1, inblocks, n_blocks*sizeof(fastd_block128_t), nonce); } @@ -215,7 +207,7 @@ static bool method_encrypt(fastd_context_t *ctx, fastd_peer_t *peer UNUSED, fast put_size(&outblocks[n_blocks+1], in.len); - ok = session->ghash->hash(session->ghash_state, &sig, outblocks+1, n_blocks+1); + ok = session->ghash->hash(session->ghash_state, &tag, outblocks+1, n_blocks+1); } if (!ok) { @@ -223,17 +215,13 @@ static bool method_encrypt(fastd_context_t *ctx, fastd_peer_t *peer UNUSED, fast 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; } @@ -244,30 +232,20 @@ static bool method_decrypt(fastd_context_t *ctx, fastd_peer_t *peer, fastd_metho if (!method_session_is_valid(ctx, session)) return false; - const uint8_t *common_nonce = in.data; - - if (common_nonce[COMMON_NONCEBYTES]) /* flags */ + uint8_t in_nonce[COMMON_NONCEBYTES]; + uint8_t flags; + int64_t age; + if (!fastd_method_handle_common_header(ctx, &session->common, &in, in_nonce, &flags, &age)) return false; - int64_t age; - if (!fastd_method_is_nonce_valid(ctx, &session->common, common_nonce, &age)) + if (flags) return false; - size_t gmac_iv_length = session->method->gmac_cipher_info->iv_length; - uint8_t gmac_nonce[gmac_iv_length]; - memset(gmac_nonce, 0, gmac_iv_length); - memcpy(gmac_nonce, common_nonce, COMMON_NONCEBYTES); - gmac_nonce[gmac_iv_length-1] = 1; - - size_t iv_length = session->method->cipher_info->iv_length; - uint8_t nonce[iv_length]; - if (iv_length) { - memset(nonce, 0, iv_length); - memcpy(nonce, common_nonce, COMMON_NONCEBYTES); - nonce[iv_length-1] = 1; - } + uint8_t nonce[session->method->cipher_info->iv_length]; + fastd_method_expand_nonce(nonce, in_nonce, sizeof(nonce)); - fastd_buffer_push_head(ctx, &in, COMMON_HEADBYTES); + uint8_t gmac_nonce[session->method->gmac_cipher_info->iv_length]; + fastd_method_expand_nonce(gmac_nonce, in_nonce, sizeof(gmac_nonce)); size_t tail_len = alignto(in.len, sizeof(fastd_block128_t))-in.len; *out = fastd_buffer_alloc(ctx, in.len, 0, tail_len); @@ -276,7 +254,7 @@ 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->gmac_cipher->crypt(session->gmac_cipher_state, outblocks, inblocks, sizeof(fastd_block128_t), gmac_nonce); @@ -289,17 +267,17 @@ 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; } fastd_buffer_push_head(ctx, out, sizeof(fastd_block128_t)); - if (!fastd_method_reorder_check(ctx, peer, &session->common, 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); } -- cgit v1.2.3