/* * 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 #include #include #include namespace Botan { namespace TLS { namespace { /* * This way all work happens at the constuctor call, and we can * rely on that happening only once in C++11. */ std::vector gather_known_ciphersuites() { std::vector ciphersuites; for(size_t i = 0; i <= 0xFFFF; ++i) { Ciphersuite suite = Ciphersuite::by_id(i); if(suite.valid()) ciphersuites.push_back(suite); } return ciphersuites; } } const std::vector& Ciphersuite::all_known_ciphersuites() { static std::vector all_ciphersuites(gather_known_ciphersuites()); return all_ciphersuites; } Ciphersuite Ciphersuite::by_name(const std::string& name) { for(auto suite : all_known_ciphersuites()) { if(suite.to_string() == name) return suite; } return Ciphersuite(); // some unknown ciphersuite } bool Ciphersuite::is_scsv(u16bit suite) { // TODO: derive from IANA file in script return (suite == 0x00FF || suite == 0x5600); } Ciphersuite::Ciphersuite(u16bit ciphersuite_code, const char* sig_algo, const char* kex_algo, const char* cipher_algo, size_t cipher_keylen, size_t nonce_bytes_from_handshake, size_t nonce_bytes_from_record, const char* mac_algo, size_t mac_keylen, const char* prf_algo) : m_ciphersuite_code(ciphersuite_code), m_sig_algo(sig_algo), m_kex_algo(kex_algo), m_prf_algo(prf_algo), m_cipher_algo(cipher_algo), m_cipher_keylen(cipher_keylen), m_nonce_bytes_from_handshake(nonce_bytes_from_handshake), m_nonce_bytes_from_record(nonce_bytes_from_record), m_mac_algo(mac_algo), m_mac_keylen(mac_keylen) { } 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"); } namespace { bool have_hash(const std::string& prf) { return (!get_hash_function_providers(prf).empty()); } bool have_cipher(const std::string& cipher) { if(!get_block_cipher_providers(cipher).empty()) return true; if(!get_stream_cipher_providers(cipher).empty()) return true; return false; } } bool Ciphersuite::valid() const { if(!m_cipher_keylen) // uninitialized object return false; if(!have_hash(prf_algo())) return false; 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 } 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; } std::string Ciphersuite::to_string() const { if(m_cipher_keylen == 0) throw std::runtime_error("Ciphersuite::to_string - no value set"); std::ostringstream out; out << "TLS_"; if(kex_algo() != "RSA") { if(kex_algo() == "DH") out << "DHE"; else if(kex_algo() == "ECDH") out << "ECDHE"; else out << kex_algo(); out << '_'; } if(sig_algo() == "DSA") out << "DSS_"; else if(sig_algo() != "") out << sig_algo() << '_'; out << "WITH_"; if(cipher_algo() == "RC4") { out << "RC4_128_"; } else if(cipher_algo() == "ChaCha20Poly1305") { out << "CHACHA20_POLY1305_"; } else { if(cipher_algo() == "3DES") out << "3DES_EDE"; else if(cipher_algo().find("Camellia") == 0) out << "CAMELLIA_" << std::to_string(8*cipher_keylen()); else { if(cipher_algo().find("OCB(12)") != std::string::npos) out << replace_chars(cipher_algo().substr(0, cipher_algo().size() - 4), {'-', '/'}, '_'); else out << replace_chars(cipher_algo(), {'-', '/'}, '_'); } if(cipher_algo().find("/") != std::string::npos) out << "_"; // some explicit mode already included else out << "_CBC_"; } if(mac_algo() == "SHA-1") out << "SHA"; else if(mac_algo() == "AEAD") out << erase_chars(prf_algo(), {'-'}); else out << erase_chars(mac_algo(), {'-'}); return out.str(); } } }