diff options
Diffstat (limited to 'src/libtls/tls_crypto.c')
-rw-r--r-- | src/libtls/tls_crypto.c | 227 |
1 files changed, 105 insertions, 122 deletions
diff --git a/src/libtls/tls_crypto.c b/src/libtls/tls_crypto.c index cc73ebaeb..03d19fa00 100644 --- a/src/libtls/tls_crypto.c +++ b/src/libtls/tls_crypto.c @@ -385,34 +385,14 @@ struct private_tls_crypto_t { tls_prf_t *prf; /** - * Signer instance for inbound traffic + * AEAD transform for inbound traffic */ - signer_t *signer_in; + tls_aead_t *aead_in; /** - * Signer instance for outbound traffic + * AEAD transform for outbound traffic */ - signer_t *signer_out; - - /** - * Crypter instance for inbound traffic - */ - crypter_t *crypter_in; - - /** - * Crypter instance for outbound traffic - */ - crypter_t *crypter_out; - - /** - * IV for input decryption, if < TLSv1.2 - */ - chunk_t iv_in; - - /** - * IV for output decryption, if < TLSv1.2 - */ - chunk_t iv_out; + tls_aead_t *aead_out; /** * EAP-[T]TLS MSK @@ -969,10 +949,66 @@ METHOD(tls_crypto_t, get_cipher_suites, int, } /** + * Create NULL encryption transforms + */ +static bool create_null(private_tls_crypto_t *this, suite_algs_t *algs) +{ + this->aead_in = tls_aead_create_null(algs->mac); + this->aead_out = tls_aead_create_null(algs->mac); + if (!this->aead_in || !this->aead_out) + { + DBG1(DBG_TLS, "selected TLS MAC %N not supported", + integrity_algorithm_names, algs->mac); + return FALSE; + } + return TRUE; +} + +/** + * Create traditional transforms + */ +static bool create_traditional(private_tls_crypto_t *this, suite_algs_t *algs) +{ + if (this->tls->get_version(this->tls) < TLS_1_1) + { + this->aead_in = tls_aead_create_implicit(algs->mac, + algs->encr, algs->encr_size); + this->aead_out = tls_aead_create_implicit(algs->mac, + algs->encr, algs->encr_size); + } + else + { + this->aead_in = tls_aead_create_explicit(algs->mac, + algs->encr, algs->encr_size); + this->aead_out = tls_aead_create_explicit(algs->mac, + algs->encr, algs->encr_size); + } + if (!this->aead_in || !this->aead_out) + { + DBG1(DBG_TLS, "selected TLS transforms %N-%u-%N not supported", + encryption_algorithm_names, algs->encr, algs->encr_size * 8, + integrity_algorithm_names, algs->mac); + return FALSE; + } + return TRUE; +} + +/** + * Clean up and unset AEAD transforms + */ +static void destroy_aeads(private_tls_crypto_t *this) +{ + DESTROY_IF(this->aead_in); + DESTROY_IF(this->aead_out); + this->aead_in = this->aead_out = NULL; +} + +/** * Create crypto primitives */ static bool create_ciphers(private_tls_crypto_t *this, suite_algs_t *algs) { + destroy_aeads(this); DESTROY_IF(this->prf); if (this->tls->get_version(this->tls) < TLS_1_2) { @@ -987,38 +1023,22 @@ static bool create_ciphers(private_tls_crypto_t *this, suite_algs_t *algs) DBG1(DBG_TLS, "selected TLS PRF not supported"); return FALSE; } - - DESTROY_IF(this->signer_in); - DESTROY_IF(this->signer_out); - this->signer_in = lib->crypto->create_signer(lib->crypto, algs->mac); - this->signer_out = lib->crypto->create_signer(lib->crypto, algs->mac); - if (!this->signer_in || !this->signer_out) - { - DBG1(DBG_TLS, "selected TLS MAC %N not supported", - integrity_algorithm_names, algs->mac); - return FALSE; - } - - DESTROY_IF(this->crypter_in); - DESTROY_IF(this->crypter_out); if (algs->encr == ENCR_NULL) { - this->crypter_in = this->crypter_out = NULL; + if (create_null(this, algs)) + { + return TRUE; + } } else { - this->crypter_in = lib->crypto->create_crypter(lib->crypto, - algs->encr, algs->encr_size); - this->crypter_out = lib->crypto->create_crypter(lib->crypto, - algs->encr, algs->encr_size); - if (!this->crypter_in || !this->crypter_out) + if (create_traditional(this, algs)) { - DBG1(DBG_TLS, "selected TLS crypter %N not supported", - encryption_algorithm_names, algs->encr); - return FALSE; + return TRUE; } } - return TRUE; + destroy_aeads(this); + return FALSE; } METHOD(tls_crypto_t, select_cipher_suite, tls_cipher_suite_t, @@ -1512,93 +1532,63 @@ static bool derive_master(private_tls_crypto_t *this, chunk_t premaster, static bool expand_keys(private_tls_crypto_t *this, chunk_t client_random, chunk_t server_random) { - chunk_t seed, block, client_write, server_write; - int mks, eks = 0, ivs = 0; + chunk_t seed, block; + chunk_t cw_mac, cw, cw_iv; + chunk_t sw_mac, sw, sw_iv; + int mklen, eklen, ivlen; - /* derive key block for key expansion */ - mks = this->signer_out->get_key_size(this->signer_out); - if (this->crypter_out) + if (!this->aead_in || !this->aead_out) { - eks = this->crypter_out->get_key_size(this->crypter_out); - if (this->tls->get_version(this->tls) < TLS_1_1) - { - ivs = this->crypter_out->get_iv_size(this->crypter_out); - } + return FALSE; } + + /* derive key block for key expansion */ + mklen = this->aead_in->get_mac_key_size(this->aead_in); + eklen = this->aead_in->get_encr_key_size(this->aead_in); + ivlen = this->aead_in->get_iv_size(this->aead_in); seed = chunk_cata("cc", server_random, client_random); - block = chunk_alloca((mks + eks + ivs) * 2); + block = chunk_alloca((mklen + eklen + ivlen) * 2); if (!this->prf->get_bytes(this->prf, "key expansion", seed, block.len, block.ptr)) { return FALSE; } - /* signer keys */ - client_write = chunk_create(block.ptr, mks); - block = chunk_skip(block, mks); - server_write = chunk_create(block.ptr, mks); - block = chunk_skip(block, mks); + /* client/server write signer keys */ + cw_mac = chunk_create(block.ptr, mklen); + block = chunk_skip(block, mklen); + sw_mac = chunk_create(block.ptr, mklen); + block = chunk_skip(block, mklen); + + /* client/server write encryption keys */ + cw = chunk_create(block.ptr, eklen); + block = chunk_skip(block, eklen); + sw = chunk_create(block.ptr, eklen); + block = chunk_skip(block, eklen); + + /* client/server write IV; TLS 1.0 implicit IVs or AEAD salt, if any */ + cw_iv = chunk_create(block.ptr, ivlen); + block = chunk_skip(block, ivlen); + sw_iv = chunk_create(block.ptr, ivlen); + block = chunk_skip(block, ivlen); + if (this->tls->is_server(this->tls)) { - if (!this->signer_in->set_key(this->signer_in, client_write) || - !this->signer_out->set_key(this->signer_out, server_write)) + if (!this->aead_in->set_keys(this->aead_in, cw_mac, cw, cw_iv) || + !this->aead_out->set_keys(this->aead_out, sw_mac, sw, sw_iv)) { return FALSE; } } else { - if (!this->signer_out->set_key(this->signer_out, client_write) || - !this->signer_in->set_key(this->signer_in, server_write)) + if (!this->aead_out->set_keys(this->aead_out, cw_mac, cw, cw_iv) || + !this->aead_in->set_keys(this->aead_in, sw_mac, sw, sw_iv)) { return FALSE; } } - /* crypter keys, and IVs if < TLSv1.2 */ - if (this->crypter_out && this->crypter_in) - { - client_write = chunk_create(block.ptr, eks); - block = chunk_skip(block, eks); - server_write = chunk_create(block.ptr, eks); - block = chunk_skip(block, eks); - - if (this->tls->is_server(this->tls)) - { - if (!this->crypter_in->set_key(this->crypter_in, client_write) || - !this->crypter_out->set_key(this->crypter_out, server_write)) - { - return FALSE; - } - } - else - { - if (!this->crypter_out->set_key(this->crypter_out, client_write) || - !this->crypter_in->set_key(this->crypter_in, server_write)) - { - return FALSE; - } - } - if (ivs) - { - client_write = chunk_create(block.ptr, ivs); - block = chunk_skip(block, ivs); - server_write = chunk_create(block.ptr, ivs); - block = chunk_skip(block, ivs); - - if (this->tls->is_server(this->tls)) - { - this->iv_in = chunk_clone(client_write); - this->iv_out = chunk_clone(server_write); - } - else - { - this->iv_out = chunk_clone(client_write); - this->iv_in = chunk_clone(server_write); - } - } - } - /* EAP-MSK */ if (this->msk_label) { @@ -1666,13 +1656,11 @@ METHOD(tls_crypto_t, change_cipher, void, { if (inbound) { - this->protection->set_cipher(this->protection, TRUE, - this->signer_in, this->crypter_in, this->iv_in); + this->protection->set_cipher(this->protection, TRUE, this->aead_in); } else { - this->protection->set_cipher(this->protection, FALSE, - this->signer_out, this->crypter_out, this->iv_out); + this->protection->set_cipher(this->protection, FALSE, this->aead_out); } } } @@ -1686,12 +1674,7 @@ METHOD(tls_crypto_t, get_eap_msk, chunk_t, METHOD(tls_crypto_t, destroy, void, private_tls_crypto_t *this) { - DESTROY_IF(this->signer_in); - DESTROY_IF(this->signer_out); - DESTROY_IF(this->crypter_in); - DESTROY_IF(this->crypter_out); - free(this->iv_in.ptr); - free(this->iv_out.ptr); + destroy_aeads(this); free(this->handshake.ptr); free(this->msk.ptr); DESTROY_IF(this->prf); |