From 8088a82a2a91d29967cef920ba780eecdf72518e Mon Sep 17 00:00:00 2001 From: Matthias Schiffer Date: Sat, 30 Nov 2013 03:19:38 +0100 Subject: Perform string-based lookup of method-related information only once --- src/methods/composed_gmac/composed_gmac.c | 138 ++++++++++++++---------------- 1 file changed, 62 insertions(+), 76 deletions(-) (limited to 'src/methods/composed_gmac/composed_gmac.c') diff --git a/src/methods/composed_gmac/composed_gmac.c b/src/methods/composed_gmac/composed_gmac.c index 0705b7d..d1627ee 100644 --- a/src/methods/composed_gmac/composed_gmac.c +++ b/src/methods/composed_gmac/composed_gmac.c @@ -25,36 +25,43 @@ #include "../../crypto.h" +#include "../../method.h" #include "../common.h" static const fastd_block128_t ZERO_BLOCK = {}; + +struct fastd_method_context { + const fastd_cipher_info_t *cipher_info; + const fastd_cipher_info_t *gmac_cipher_info; + const fastd_mac_info_t *ghash_info; +}; + struct fastd_method_session_state { fastd_method_common_t common; - const fastd_cipher_info_t *cipher_info; + const fastd_method_context_t *ctx; + const fastd_cipher_t *cipher; fastd_cipher_state_t *cipher_state; - const fastd_cipher_info_t *gmac_cipher_info; const fastd_cipher_t *gmac_cipher; fastd_cipher_state_t *gmac_cipher_state; - const fastd_mac_info_t *ghash_info; const fastd_mac_t *ghash; fastd_mac_state_t *ghash_state; }; -static bool cipher_get(fastd_context_t *ctx, const char *name, - const fastd_cipher_info_t **cipher_info, const fastd_cipher_t **cipher, - const fastd_cipher_info_t **gmac_cipher_info, const fastd_cipher_t **gmac_cipher) { - if (!fastd_mac_info_get_by_name("ghash")) +static bool method_create_by_name(const char *name, fastd_method_context_t **method_ctx) { + fastd_method_context_t ctx; + + ctx.ghash_info = fastd_mac_info_get_by_name("ghash"); + if (!ctx.ghash_info) return false; size_t len = strlen(name); - if (len < 5) return false; @@ -73,76 +80,52 @@ static bool cipher_get(fastd_context_t *ctx, const char *name, *gmac_cipher_name = 0; gmac_cipher_name++; - const fastd_cipher_info_t *info = NULL; - const fastd_cipher_info_t *gmac_info = NULL; - - if (ctx) { - *cipher = fastd_cipher_get_by_name(ctx, cipher_name, &info); - *gmac_cipher = fastd_cipher_get_by_name(ctx, gmac_cipher_name, &gmac_info); - if (!(*cipher && *gmac_cipher)) - return false; - } - else { - info = fastd_cipher_info_get_by_name(cipher_name); - gmac_info = fastd_cipher_info_get_by_name(gmac_cipher_name); - if (!(info && gmac_info)) - return false; - } - - if (cipher_info) - *cipher_info = info; - - if (gmac_cipher_info) - *gmac_cipher_info = gmac_info; - - return true; -} - + ctx.cipher_info = fastd_cipher_info_get_by_name(cipher_name); + if (!ctx.cipher_info) + return false; -static bool method_provides(const char *name) { - const fastd_cipher_info_t *gmac_cipher_info; + if (ctx.cipher_info->iv_length && ctx.cipher_info->iv_length <= COMMON_NONCEBYTES) + return false; - if (!cipher_get(NULL, name, NULL, NULL, &gmac_cipher_info, NULL)) + ctx.gmac_cipher_info = fastd_cipher_info_get_by_name(gmac_cipher_name); + if (!ctx.gmac_cipher_info) return false; - if (gmac_cipher_info->iv_length <= COMMON_NONCEBYTES) + if (ctx.gmac_cipher_info->iv_length <= COMMON_NONCEBYTES) return false; + *method_ctx = malloc(sizeof(fastd_method_context_t)); + **method_ctx = ctx; + return true; } -static size_t method_key_length(fastd_context_t *ctx, const char *name) { - const fastd_cipher_info_t *cipher_info; - const fastd_cipher_info_t *gmac_cipher_info; +static void method_destroy(fastd_method_context_t *method_ctx) { + free(method_ctx); +} - if (!cipher_get(NULL, name, &cipher_info, NULL, &gmac_cipher_info, NULL)) - exit_bug(ctx, "composed-gmac: can't get cipher key length"); - return cipher_info->key_length + gmac_cipher_info->key_length; +static size_t method_key_length(fastd_context_t *ctx UNUSED, const fastd_method_context_t *method_ctx) { + return method_ctx->cipher_info->key_length + method_ctx->gmac_cipher_info->key_length; } -static fastd_method_session_state_t* method_session_init(fastd_context_t *ctx, const char *name, const uint8_t *secret, bool initiator) { +static fastd_method_session_state_t* method_session_init(fastd_context_t *ctx, const fastd_method_context_t *method_ctx, 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->ctx = method_ctx; - if (!cipher_get(ctx, name, - &session->cipher_info, &session->cipher, - &session->gmac_cipher_info, &session->gmac_cipher)) - exit_bug(ctx, "composed-gmac: can't instanciate cipher"); - + session->cipher = fastd_cipher_get(ctx, session->ctx->cipher_info); session->cipher_state = session->cipher->init(ctx, secret); - if (session->cipher_info->iv_length && session->cipher_info->iv_length <= COMMON_NONCEBYTES) - exit_bug(ctx, "composed-gmac: iv_length to small"); - session->gmac_cipher_state = session->gmac_cipher->init(ctx, secret + session->cipher_info->key_length); - if (session->gmac_cipher_info->iv_length <= COMMON_NONCEBYTES) - exit_bug(ctx, "composed-gmac: GMAC cipher iv_length to small"); + session->gmac_cipher = fastd_cipher_get(ctx, session->ctx->gmac_cipher_info); + session->gmac_cipher_state = session->gmac_cipher->init(ctx, secret + session->ctx->cipher_info->key_length); fastd_block128_t H; - uint8_t zeroiv[session->gmac_cipher_info->iv_length]; - memset(zeroiv, 0, session->gmac_cipher_info->iv_length); + size_t gmac_iv_length = session->ctx->gmac_cipher_info->iv_length; + uint8_t zeroiv[gmac_iv_length]; + memset(zeroiv, 0, gmac_iv_length); if (!session->gmac_cipher->crypt(ctx, session->gmac_cipher_state, &H, &ZERO_BLOCK, sizeof(fastd_block128_t), zeroiv)) { session->cipher->free(ctx, session->cipher_state); @@ -152,10 +135,7 @@ static fastd_method_session_state_t* method_session_init(fastd_context_t *ctx, c return NULL; } - session->ghash = fastd_mac_get_by_name(ctx, "ghash", &session->ghash_info); - if (!session->ghash) - exit_bug(ctx, "composed-gmac: can't instanciate ghash mac"); - + session->ghash = fastd_mac_get(ctx, session->ctx->ghash_info); session->ghash_state = session->ghash->init(ctx, H.b); return session; @@ -209,19 +189,21 @@ static bool method_encrypt(fastd_context_t *ctx, fastd_peer_t *peer UNUSED, fast fastd_block128_t *outblocks = out->data; fastd_block128_t sig; - uint8_t gmac_nonce[session->gmac_cipher_info->iv_length]; - memset(gmac_nonce, 0, session->gmac_cipher_info->iv_length); + size_t gmac_iv_length = session->ctx->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[session->gmac_cipher_info->iv_length-1] = 1; + gmac_nonce[gmac_iv_length-1] = 1; bool ok = session->gmac_cipher->crypt(ctx, session->gmac_cipher_state, outblocks, &ZERO_BLOCK, sizeof(fastd_block128_t), gmac_nonce); if (ok) { - uint8_t nonce[session->cipher_info->iv_length]; - if (session->cipher_info->iv_length) { - memset(nonce, 0, session->cipher_info->iv_length); + size_t iv_length = session->ctx->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[session->cipher_info->iv_length-1] = 1; + nonce[iv_length-1] = 1; } ok = session->cipher->crypt(ctx, session->cipher_state, outblocks+1, inblocks, n_blocks*sizeof(fastd_block128_t), nonce); @@ -271,16 +253,18 @@ static bool method_decrypt(fastd_context_t *ctx, fastd_peer_t *peer, fastd_metho if (!fastd_method_is_nonce_valid(ctx, &session->common, common_nonce, &age)) return false; - uint8_t gmac_nonce[session->gmac_cipher_info->iv_length]; - memset(gmac_nonce, 0, session->gmac_cipher_info->iv_length); + size_t gmac_iv_length = session->ctx->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[session->gmac_cipher_info->iv_length-1] = 1; + gmac_nonce[gmac_iv_length-1] = 1; - uint8_t nonce[session->cipher_info->iv_length]; - if (session->cipher_info->iv_length) { - memset(nonce, 0, session->cipher_info->iv_length); + size_t iv_length = session->ctx->cipher_info->iv_length; + uint8_t nonce[iv_length]; + if (iv_length) { + memset(nonce, 0, iv_length); memcpy(nonce, common_nonce, COMMON_NONCEBYTES); - nonce[session->cipher_info->iv_length-1] = 1; + nonce[iv_length-1] = 1; } fastd_buffer_push_head(ctx, &in, COMMON_HEADBYTES); @@ -326,15 +310,17 @@ static bool method_decrypt(fastd_context_t *ctx, fastd_peer_t *peer, fastd_metho } const fastd_method_t fastd_method_composed_gmac = { - .provides = method_provides, - .max_overhead = COMMON_HEADBYTES + sizeof(fastd_block128_t), .min_encrypt_head_space = 0, .min_decrypt_head_space = 0, .min_encrypt_tail_space = sizeof(fastd_block128_t)-1, .min_decrypt_tail_space = 2*sizeof(fastd_block128_t)-1, + .create_by_name = method_create_by_name, + .destroy = method_destroy, + .key_length = method_key_length, + .session_init = method_session_init, .session_is_valid = method_session_is_valid, .session_is_initiator = method_session_is_initiator, -- cgit v1.2.3