diff options
Diffstat (limited to 'src/methods/generic_gmac/generic_gmac.c')
| -rw-r--r-- | src/methods/generic_gmac/generic_gmac.c | 99 |
1 files changed, 42 insertions, 57 deletions
diff --git a/src/methods/generic_gmac/generic_gmac.c b/src/methods/generic_gmac/generic_gmac.c index 4de7ad8..91b96cb 100644 --- a/src/methods/generic_gmac/generic_gmac.c +++ b/src/methods/generic_gmac/generic_gmac.c @@ -25,28 +25,37 @@ #include "../../crypto.h" +#include "../../method.h" #include "../common.h" +struct fastd_method_context { + const fastd_cipher_info_t *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_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) { - 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; @@ -60,70 +69,42 @@ static bool cipher_get(fastd_context_t *ctx, const char *name, const fastd_ciphe memcpy(cipher_name, name, len-5); cipher_name[len-5] = 0; - const fastd_cipher_info_t *info = NULL; - - if (ctx) { - *cipher = fastd_cipher_get_by_name(ctx, cipher_name, &info); - if (!*cipher) - return false; - } - else { - info = fastd_cipher_info_get_by_name(cipher_name); - if (!info) - return false; - } + ctx.cipher_info = fastd_cipher_info_get_by_name(cipher_name); + if (!ctx.cipher_info) + return false; - if (info->iv_length <= COMMON_NONCEBYTES) + if (ctx.cipher_info->iv_length <= COMMON_NONCEBYTES) return false; - if (cipher_info) - *cipher_info = info; + *method_ctx = malloc(sizeof(fastd_method_context_t)); + **method_ctx = ctx; return true; } - -static bool method_provides(const char *name) { - return cipher_get(NULL, name, NULL, NULL); +static void method_destroy(fastd_method_context_t *method_ctx) { + free(method_ctx); } -static size_t method_key_length(fastd_context_t *ctx, const char *name) { - const fastd_cipher_info_t *cipher_info; - if (!cipher_get(NULL, name, &cipher_info, NULL)) - exit_bug(ctx, "generic-gmac: can't get cipher key length"); - - return cipher_info->key_length + sizeof(fastd_block128_t); +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->ghash_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)) - exit_bug(ctx, "generic-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 <= COMMON_NONCEBYTES) - exit_bug(ctx, "generic-gmac: iv_length to small"); - - session->ghash = fastd_mac_get_by_name(ctx, "ghash", &session->ghash_info); - if (!session->ghash) - exit_bug(ctx, "generic-gmac: can't instanciate ghash mac"); - - session->ghash_state = session->ghash->init(ctx, secret + session->cipher_info->key_length); + session->ghash = fastd_mac_get(ctx, session->ctx->ghash_info); + session->ghash_state = session->ghash->init(ctx, secret + session->ctx->cipher_info->key_length); 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, "generic-gmac: 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)); } @@ -168,10 +149,11 @@ 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->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]; + 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; int n_blocks = block_count(in.len, sizeof(fastd_block128_t)); @@ -221,10 +203,12 @@ 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->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]; + memset(nonce, 0, iv_length); memcpy(nonce, in.data, COMMON_NONCEBYTES); - nonce[session->cipher_info->iv_length-1] = 1; + nonce[iv_length-1] = 1; int64_t age; if (!fastd_method_is_nonce_valid(ctx, &session->common, nonce, &age)) @@ -270,17 +254,18 @@ static bool method_decrypt(fastd_context_t *ctx, fastd_peer_t *peer, fastd_metho } const fastd_method_t fastd_method_generic_gmac = { - .provides = method_provides, - .max_overhead = COMMON_HEADBYTES + sizeof(fastd_block128_t), .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, + .create_by_name = method_create_by_name, + .destroy = method_destroy, + .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, |