/* * TLS Cipher Suite * (C) 2004-2010,2012,2013 Jack Lloyd * * Botan is released under the Simplified BSD License (see license.txt) */ #include #include #include #include #include #include namespace Botan { namespace TLS { bool Ciphersuite::is_scsv(uint16_t suite) { // TODO: derive from IANA file in script return (suite == 0x00FF || suite == 0x5600); } bool Ciphersuite::psk_ciphersuite() const { return (kex_algo() == "PSK" || kex_algo() == "DHE_PSK" || kex_algo() == "ECDHE_PSK"); } bool Ciphersuite::ecc_ciphersuite() const { return (sig_algo() == "ECDSA" || kex_algo() == "ECDH" || kex_algo() == "ECDHE_PSK"); } bool Ciphersuite::cbc_ciphersuite() const { return (mac_algo() != "AEAD"); } Ciphersuite Ciphersuite::by_id(uint16_t suite) { const std::vector& all_suites = all_known_ciphersuites(); auto s = std::lower_bound(all_suites.begin(), all_suites.end(), suite); if(s != all_suites.end() && s->ciphersuite_code() == suite) { return *s; } return Ciphersuite(); // some unknown ciphersuite } namespace { bool have_hash(const std::string& prf) { return (HashFunction::providers(prf).size() > 0); } bool have_cipher(const std::string& cipher) { return (BlockCipher::providers(cipher).size() > 0) || (StreamCipher::providers(cipher).size() > 0); } } bool Ciphersuite::is_usable() const { if(!m_cipher_keylen) // uninitialized object return false; if(!have_hash(prf_algo())) return false; #if !defined(BOTAN_HAS_TLS_CBC) if(cbc_ciphersuite()) return false; #endif if(mac_algo() == "AEAD") { if(cipher_algo() == "ChaCha20Poly1305") { #if !defined(BOTAN_HAS_AEAD_CHACHA20_POLY1305) return false; #endif } else { auto cipher_and_mode = split_on(cipher_algo(), '/'); BOTAN_ASSERT(cipher_and_mode.size() == 2, "Expected format for AEAD algo"); if(!have_cipher(cipher_and_mode[0])) return false; const auto mode = cipher_and_mode[1]; #if !defined(BOTAN_HAS_AEAD_CCM) if(mode == "CCM" || mode == "CCM-8") return false; #endif #if !defined(BOTAN_HAS_AEAD_GCM) if(mode == "GCM") return false; #endif #if !defined(BOTAN_HAS_AEAD_OCB) if(mode == "OCB(12)" || mode == "OCB") return false; #endif } } else { // Old non-AEAD schemes if(!have_cipher(cipher_algo())) return false; if(!have_hash(mac_algo())) // HMAC return false; } if(kex_algo() == "SRP_SHA") { #if !defined(BOTAN_HAS_SRP6) return false; #endif } else if(kex_algo() == "ECDH" || kex_algo() == "ECDHE_PSK") { #if !defined(BOTAN_HAS_ECDH) return false; #endif } else if(kex_algo() == "DH" || kex_algo() == "DHE_PSK") { #if !defined(BOTAN_HAS_DIFFIE_HELLMAN) return false; #endif } else if(kex_algo() == "CECPQ1") { #if !defined(BOTAN_HAS_CECPQ1) return false; #endif } if(sig_algo() == "DSA") { #if !defined(BOTAN_HAS_DSA) return false; #endif } else if(sig_algo() == "ECDSA") { #if !defined(BOTAN_HAS_ECDSA) return false; #endif } else if(sig_algo() == "RSA") { #if !defined(BOTAN_HAS_RSA) return false; #endif } return true; } } }