pike.git/lib/modules/SSL.pmod/Context.pike:edb6e9ce062f8fdd61b468bf72506bb7c6e160bd

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1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 #pike __REAL_VERSION__ #pragma strict_types #require constant(Crypto.Hash) //! Keeps the state that is shared by all SSL-connections on a client, //! or for one port on a server. It includes policy configuration, //! the server or client certificate(s), the corresponding private key(s), //! etc. It also includes the session cache. //! //! The defaults are usually suitable for a client, but for a server //! some configuration is necessary. //! //! Typical use is to: //! @ul //! @item //! Call @[add_cert()] with the certificates belonging to the server //! or client. Note that clients often don't have or need any //! certificates, and also that certificate-less server operation is //! possible, albeit discouraged and not enabled by default. //! //! Suitable self-signed certificates can be created with //! @[Standards.X509.make_selfsigned_certificate()]. //! @item //! Optionally call @[get_suites()] to get a set of cipher_suites //! to assign to @[preferred_suites]. This is only needed if the //! default set of suites from @expr{get_suites(128, 1)@} isn't //! satisfactory. //! @endul //! //! The initialized @[Context] object is then passed to //! @[File()->create()] or used as is embedded in @[Port]. //! //! @seealso //! @[File], @[Port], @[Standards.X509] #include "tls.h" import "."; import Constants; protected void create() { SSL3_DEBUG_MSG("SSL.Context->create\n"); /* Backwards compatibility */ multiset(int) blocked = (< CIPHER_rc4 >); preferred_suites = get_suites(128, 1, blocked); } //! List of supported versions, in order of preference. Defaults to //! @[PROTOCOL_TLS_1_2], @[PROTOCOL_TLS_1_1] and @[PROTOCOL_TLS_1_0]. array(ProtocolVersion) supported_versions = ({ PROTOCOL_TLS_1_2, PROTOCOL_TLS_1_1, PROTOCOL_TLS_1_0, }); //! Returns a list of possible versions to use, given the version in //! the client hello header. array(ProtocolVersion) get_versions(ProtocolVersion client) { // Do we support exactly the version the client advertise? int pos = search(supported_versions, client); if(pos!=-1) return supported_versions[pos..]; // Client is TLS 1.2 and we have something later supported? Then we // expect supported_versions extension. int high = max(@supported_versions); if( client==PROTOCOL_TLS_1_2 && high > PROTOCOL_TLS_1_2 ) return ({ PROTOCOL_IN_EXTENSION }); // Return all versions lower than the given client version. return filter(supported_versions, lambda(ProtocolVersion v) { return v<client; }); } //! List of advertised protocols using using TLS application level //! protocol negotiation. array(string(8bit)) advertised_protocols; //! Mapping of supported verifier algorithms to hash implementation. //! //! @seealso //! @[Standards.X509.get_algorithms()] mapping(Standards.ASN1.Types.Identifier:Crypto.Hash) verifier_algorithms = filter(Standards.X509.get_algorithms(), lambda(object o) { return !(< #if constant(Crypto.MD2) Crypto.MD2, #endif Crypto.MD5, Crypto.SHA1 >)[o]; }); //! The maximum amount of data that is sent in each SSL packet by //! @[File]. A value between 1 and @[Constants.PACKET_MAX_SIZE]. int packet_max_size = PACKET_MAX_SIZE; //! Lists the supported compression algorithms in order of preference. //! //! Defaults to @expr{({ COMPRESSION_null })@} due to SSL attacks that //! target compression. array(int) preferred_compressors = ({ COMPRESSION_null }); //! If set enable SSL/TLS protocol renegotiation. //! //! Defaults to @expr{1@} (enabled). //! //! @note //! @rfc{7540:9.2.1@} requires this to be turned off after //! @[Protocols.HTTP2] communication has started. int(0..1) enable_renegotiation = 1; //! If set, the other peer will be probed for the heartbleed bug //! during handshake. If heartbleed is found the connection is closed //! with insufficient security fatal error. Requires //! @expr{Constants.EXTENSION_heartbeat@} to be set in @[extensions]. int(0..1) heartbleed_probe = 0; //! @decl Alert alert_factory(SSL.Connection con, int level, int description, @ //! ProtocolVersion version, @ //! string|void message, mixed|void trace) //! //! Alert factory. //! //! This function may be overloaded to eg obtain logging of //! generated alerts. //! //! @param con //! Connection which caused the alert. //! //! @param level //! Level of alert. //! //! @param description //! Description code for the alert. //! //! @param message //! Optional log message for the alert. //! //! @note //! Not all alerts are fatal, and some (eg @[ALERT_close_notify]) are used //! during normal operation. Alert alert_factory(object con, int(1..2) level, int(8bit) description, ProtocolVersion version, string|void message) { return Alert(level, description, version, message); } //! A list of all extensions that will be considered in the handshake //! process. Extensions not listed will not be sent, and will be //! ignored if received. //! //! The following values are included by default. //! @int //! @value Constants.EXTENSION_renegotiation_info //! Protection against renegotiation attack (@rfc{5746@}). //! @value Constants.EXTENSION_max_fragment_length //! Allows negotiation of the maximum fragment size (@rfc{6066:4@}). //! @value Constants.EXTENSION_encrypt_then_mac //! Attempts to address attacks against block //! ciphers (@rfc{7366@}). //! @value Constants.EXTENSION_application_layer_protocol_negotiation //! Required to support more than one protocol on the same TLS //! port (@rfc{7639@}). //! @value Constants.EXTENSION_signature_algorithms //! Required to select which out of several certificates to use //! (@rfc{5246:7.4.1.4.1@}). //! @value Constants.EXTENSION_ec_point_formats //! Required for elliptic curve key exchange (@rfc{4492:5.1.2@}). //! @value Constants.EXTENSION_elliptic_curves //! Required for elliptic curve key exchange (@rfc{4492:5.1.1@}). //! @value Constants.EXTENSION_server_name //! Allows the client to select which of several domains hosted on //! the same server it wants to connect to. Required by many //! websites (@rfc{6066:3@}). //! @value Constants.EXTENSION_session_ticket //! Support session resumption without server-side state //! (@rfc{4507@} and @rfc{5077@}). //! @value Constants.EXTENSION_next_protocol_negotiation //! Not supported by Pike. The server side will just check that //! the client packets are correctly formatted. //! @value Constants.EXTENSION_signed_certificate_timestamp //! Not supported by Pike. The server side will just check that //! the client packets are correctly formatted. //! @value Constants.EXTENSION_early_data //! Needed for TLS 1.3 0-RTT handshake. EXPERIMENTAL. //! @value Constants.EXTENSION_padding //! This extension is required to avoid a bug in some f5 SSL //! terminators for certain sizes of client handshake messages. //! @endint //! //! The following supported values are not included by default. //! @int //! @value Constants.EXTENSION_truncated_hmac //! This extension allows for the HMAC to be truncated for a small //! win in payload size. Not widely implemented and may be a //! security risk (@rfc{6066:7@}). //! @value Constants.EXTENSION_heartbeat //! This extension allows the client and server to send heartbeats //! over the connection. Intended to keep TCP connections //! alive. Required to be set to use @[heartbleed_probe] //! (@rfc{6520@}). //! @value Constants.EXTENSION_extended_master_secret //! Binds the master secret to important session parameters to //! protect against man in the middle attacks (@rfc{7627@}). //! @endint //! //! @seealso //! @rfc{6066@} multiset(int) extensions = (< EXTENSION_renegotiation_info, EXTENSION_max_fragment_length, EXTENSION_ec_point_formats, EXTENSION_encrypt_then_mac, EXTENSION_application_layer_protocol_negotiation, EXTENSION_signature_algorithms, EXTENSION_elliptic_curves, EXTENSION_server_name, EXTENSION_session_ticket, EXTENSION_next_protocol_negotiation, EXTENSION_signed_certificate_timestamp, EXTENSION_early_data, EXTENSION_padding, >); // // --- Cryptography // //! Used to generate random cookies for the hello-message. If we use //! the RSA keyexchange method, and this is a server, this random //! number generator is not used for generating the master_secret. By //! default set to @[random_string]. function(int(0..):string(8bit)) random = random_string; //! Cipher suites we want to support, in order of preference, best //! first. By default set to all suites with at least 128 bits cipher //! key length, excluding RC4, and ephemeral and non-ephemeral //! certificate based key exchange. array(int) preferred_suites; //! Supported elliptical curve cipher curves in order of //! preference. Defaults to all supported curves, ordered with the //! largest curves first. array(int) ecc_curves = reverse(sort(indices(ECC_CURVES))); //! Supported FFDHE groups for DHE key exchanges, in order of preference, //! most preferred first. //! //! Defaults to the full set of supported FFDHE groups from the FFDHE //! draft, in order of size with the smallest group (2048 bits) first. //! //! Server-side the first group in the list that satisfies the NIST guide //! lines for key strength (NIST SP800-57 5.6.1) (if any) for the selected //! cipher suite will be selected, and otherwise the largest group. //! //! Client-side the list will be reversed (as a precaution if the server //! actually follows the clients preferences). array(int) ffdhe_groups = sort(indices(FFDHE_GROUPS)); //! DHE parameter lookup for the FFDHE private range. //! //! Add any custom FFDHE-groups here. //! //! Defaults to the empty mapping. //! //! @note //! If you add any groups here, you will also need to update //! @[ffdhe_groups] accordingly. mapping(int(508..511):Crypto.DH.Parameters) private_ffdhe_groups = ([]); //! The set of <hash, signature> combinations to use by us. //! //! Only used with TLS 1.2 and later. //! //! Defaults to all combinations supported by Pike except for MD5. //! //! This list is typically filtered by @[get_signature_algorithms()] //! to get rid of combinations not supported by the runtime. //! //! @note //! According to @rfc{5246:7.4.2@} all certificates need to be //! signed by any of the supported signature algorithms. To be //! forward compatible this list needs to be limited to the //! combinations that have existing PKCS identifiers. //! //! @seealso //! @[get_signature_algorithms()] array(int) signature_algorithms = ({ #if constant(Crypto.SHA512) #if constant(Crypto.ECC.Curve) SIGNATURE_ecdsa_secp521r1_sha512, #endif SIGNATURE_rsa_pkcs1_sha512, #endif #if constant(Crypto.SHA384) #if constant(Crypto.ECC.Curve) SIGNATURE_ecdsa_secp384r1_sha384, #endif SIGNATURE_rsa_pkcs1_sha384, #endif #if constant(Crypto.ECC.Curve25519) SIGNATURE_ed25519_intrinsic, #endif #if constant(Crypto.ECC.Curve) SIGNATURE_ecdsa_secp256r1_sha256, #endif HASH_sha256 | SIGNATURE_dsa, SIGNATURE_rsa_pkcs1_sha256, #if constant(Crypto.SHA224) #if constant(Crypto.ECC.Curve) HASH_sha224 | SIGNATURE_ecdsa, #endif HASH_sha224 | SIGNATURE_dsa, #endif #if constant(Crypto.ECC.Curve) HASH_sha1 | SIGNATURE_ecdsa, #endif HASH_sha1 | SIGNATURE_dsa, SIGNATURE_rsa_pkcs1_sha1, }); //! Get the (filtered) set of locally supported signature algorithms. //! //! @seealso //! @[signature_algorithms] array(int) get_signature_algorithms(array(int)|void signature_algorithms) { if (!signature_algorithms) { signature_algorithms = this_program::signature_algorithms; } #if constant(Crypto.ECC.Curve) && constant(Crypto.SHA512) && \ constant(Crypto.SHA384) && constant(Crypto.SHA224) && \ constant(Crypto.ECC.Curve25519) return signature_algorithms; #else return [array(int)] filter(signature_algorithms, lambda(SignatureScheme scheme) { #if !constant(Crypto.ECC.Curve) if ((scheme & SIGNATURE_MASK) == SIGNATURE_ecdsa) return 0; #endif if ((< #if constant(Crypto.ECC.Curve25519) SIGNATURE_ed25519_intrinsic, #endif >)[scheme]) return 1; if ((< #if !constant(Crypto.SHA512) HASH_sha512, #endif #if !constant(Crypto.SHA384) HASH_sha384, #endif #if !constant(Crypto.SHA224) HASH_sha224, #endif HASH_intrinsic, >)[scheme & HASH_MASK]) return 0; return 1; }); #endif } // Generate a sort key for a cipher suite. // // The larger the value, the stronger the cipher suite. protected int cipher_suite_sort_key(int suite) { array(int) info = [array(int)] (CIPHER_SUITES[suite] || ({ 0, 0, 0 })); int keylength = CIPHER_effective_keylengths[info[1]]; // NB: Currently the hash algorithms are allocated in a suitable order. // NB: The hash values are shifted 8 bits. int hash = info[2] >> 8; // Adjust for the cipher mode. if (sizeof(info) > 3) { hash |= info[3]<<5; if (info[3] == MODE_cbc) { // CBC. keylength >>= 1; } } else { // Old suite; CBC or RC4. // This adjustment is to make some browsers (like eg Chrome) // stop complaining, by preferring AES128/GCM to AES256/CBC. keylength >>= 1; } // NB: As are the cipher ids if you disregard the keylengths. int cipher = info[1]; // FIXME: I'm not quite sure about the priorities here. int ke_prio = ([ KE_null: 0, KE_dh_anon: 1, KE_ecdh_anon: 2, KE_fortezza: 3, KE_dms: 4, KE_rsa_export: 5, KE_dh_rsa: 6, KE_dh_dss: 7, KE_rsa: 8, KE_rsa_fips: 9, KE_ecdh_rsa: 10, KE_ecdh_ecdsa: 11, KE_dhe_rsa: 12, KE_dhe_dss: 13, KE_ecdhe_rsa: 14, KE_ecdhe_ecdsa: 15, ])[info[0]]; int auth_prio = keylength && ([ KE_null: 0, KE_dh_anon: 0, KE_ecdh_anon: 0, KE_fortezza: 1, KE_dms: 2, KE_rsa_export: 4, // cf FREAK-attack. KE_rsa: 8, KE_rsa_fips: 8, KE_dhe_rsa: 8, KE_ecdhe_rsa: 8, KE_dh_dss: 8, KE_dh_rsa: 8, KE_dhe_dss: 8, KE_ecdh_rsa: 8, KE_ecdh_ecdsa: 8, KE_ecdhe_ecdsa: 8, ])[info[0]]; // int not_anonymous = ke_prio >= 3; // Klugde to test GCM. // if (sizeof(info) > 3) keylength += 0x100; // NB: 8 bits for cipher. // 8 bits for hash + mode. // 8 bits for key exchange. // 12 bits for keylength. // 4 bits for auth. return cipher | hash << 8 | ke_prio << 16 | keylength << 24 | auth_prio << 36; } //! Sort a set of cipher suites according to our preferences. //! //! @returns //! Returns the array sorted with the most preferrable (aka "best") //! cipher suite first. //! //! @note //! The original array (@[suites]) is modified destructively, //! but is not the same array as the result. array(int) sort_suites(array(int) suites) { sort(map(suites, cipher_suite_sort_key), suites); return reverse(suites); } //! Get the prioritized list of supported cipher suites //! that satisfy the requirements. //! //! @param min_keylength //! Minimum supported effective keylength in bits. Defaults to @expr{128@}. //! Specify @expr{-1@} to enable null ciphers. //! //! @param ke_mode //! Level of protection for the key exchange. //! @int //! @value 0 //! Require forward secrecy (ephemeral keys). //! @value 1 //! Also allow certificate based key exchanges. //! @value 2 //! Also allow anonymous server key exchange. Note that this //! allows for man in the middle attacks. //! @endint //! //! @param blacklisted_ciphers //! Multiset of ciphers that are NOT to be used. By default RC4, DES //! and export ciphers are blacklisted. An empty multiset needs to //! be given to unlock these. //! //! @param blacklisted_kes //! Multiset of key exchange methods that are NOT to be used. //! //! @param blacklisted_hashes //! Multiset of hash algoriths that are NOT to be used. //! //! @param blacklisted_ciphermodes //! Multiset of cipher modes that are NOT to be used. //! //! @note //! The list of suites is also filtered on the current settings of //! @[supported_versions]. //! //! @note //! Note that the effective keylength may differ from //! the actual keylength for old ciphers where there //! are known attacks. array(int) get_suites(int(-1..)|void min_keylength, int(0..2)|void ke_mode, multiset(int)|void blacklisted_ciphers, multiset(KeyExchangeType)|void blacklisted_kes, multiset(HashAlgorithm)|void blacklisted_hashes, multiset(CipherModes)|void blacklisted_ciphermodes) { if (!min_keylength) min_keylength = 128; // Reasonable default. // Ephemeral key exchange methods. multiset(int) kes = (< KE_dhe_rsa, KE_dhe_dss, KE_ecdhe_rsa, KE_ecdhe_ecdsa, >); if (ke_mode) { // Static certificate based key exchange methods. kes |= (< KE_rsa, KE_rsa_export, KE_rsa_fips, KE_dh_rsa, KE_dh_dss, #if constant(Crypto.ECC.Curve) KE_ecdh_rsa, KE_ecdh_ecdsa, #endif >); if (ke_mode == 2) { // Unsigned key exchange methods. kes |= (< KE_null, KE_dh_anon, #if constant(Crypto.ECC.Curve) KE_ecdh_anon, #endif >); } } #if constant(Crypto.ECC.Curve) if (!sizeof(ecc_curves)) { // No ECC curves available ==> No support for ECC. kes -= (< KE_ecdhe_rsa, KE_ecdhe_ecdsa, KE_ecdh_rsa, KE_ecdh_ecdsa, KE_ecdh_anon, >); } #endif if (blacklisted_kes) { kes -= blacklisted_kes; } // Filter unsupported key exchange methods. array(int) res = filter(indices(CIPHER_SUITES), lambda(int suite) { return kes[CIPHER_SUITES[suite][0]]; }); // Filter short effective key lengths. if (min_keylength > 0) { res = filter(res, lambda(int suite, int min_keylength) { return min_keylength <= CIPHER_effective_keylengths[CIPHER_SUITES[suite][1]]; }, min_keylength); } if( !blacklisted_ciphers || (max_version >= PROTOCOL_TLS_1_3)) { // Block export ciphers and DES by default because they are // demonstrably broken. // // Block RC4 because it probably is (RFC 7465). // // TLS 1.3 prohibits RC4. if (!blacklisted_ciphers) blacklisted_ciphers = (<>); blacklisted_ciphers |= (< CIPHER_rc4, CIPHER_des, CIPHER_rc4_40, CIPHER_rc2_40, CIPHER_des40 >); } if( sizeof(blacklisted_ciphers) ) res = filter(res, lambda(int suite, multiset(int) blacklisted_hashes) { return !blacklisted_hashes[CIPHER_SUITES[suite][1]]; }, blacklisted_ciphers); #if !constant(Crypto.SHA384) // Filter suites needing SHA384 as our Nettle doesn't support it. if (!blacklisted_hashes) blacklisted_hashes = (< HASH_sha384 >); else blacklisted_hashes[HASH_sha384] = 1; #endif if (blacklisted_hashes) { res = filter(res, lambda(int suite, multiset(int) blacklisted_hashes) { return !blacklisted_hashes[CIPHER_SUITES[suite][2]]; }, blacklisted_hashes); } if (blacklisted_ciphermodes) { res = filter(res, lambda(int suite, multiset(int) blacklisted_ciphermodes) { array(int) info = [array(int)]CIPHER_SUITES[suite]; int mode = (sizeof(info) > 3)?info[3]:MODE_cbc; return !blacklisted_ciphermodes[mode]; }, blacklisted_ciphermodes); } switch(min(@supported_versions)) { case PROTOCOL_TLS_1_3: res = filter(res, lambda(int suite) { array(int) info = [array(int)]CIPHER_SUITES[suite]; // Non-AEAD suites were obsoleted in TLS 1.3. if (sizeof(info) < 4) return 0; if (info[3] == MODE_cbc) return 0; return 1; }); break; case PROTOCOL_TLS_1_2: res = filter(res, lambda(int suite) { array(int) info = [array(int)]CIPHER_SUITES[suite]; switch(info[1]) { // Export cipher suites were removed in TLS 1.1. case 0: case CIPHER_rc2_40: case CIPHER_rc4_40: case CIPHER_des40: // IDEA and DES suites were removed in TLS 1.2. case CIPHER_idea: case CIPHER_des: return 0; } return 1; }); break; case PROTOCOL_TLS_1_1: res = filter(res, lambda(int suite) { array(int) info = [array(int)]CIPHER_SUITES[suite]; // Export cipher suites were removed in TLS 1.1. switch(info[1]) { case 0: case CIPHER_rc2_40: case CIPHER_rc4_40: case CIPHER_des40: return 0; } return 1; }); break; } switch(max(@supported_versions)) { case PROTOCOL_TLS_1_1: case PROTOCOL_TLS_1_0: case PROTOCOL_SSL_3_0: res = filter(res, lambda(int suite) { array(int) info = [array(int)]CIPHER_SUITES[suite]; // AEAD suites are not supported in TLS versions // prior to TLS 1.2. // Hashes other than md5 or sha1 are not supported // prior to TLS 1.2. return (sizeof(info) < 4) && (info[2] <= HASH_sha1); }); break; } // Sort and return. return sort_suites(res); } //! Filter cipher suites from @[preferred_suites] that don't have a //! key with an effective length of at least @[min_keylength] bits. void filter_weak_suites(int min_keylength) { if (!preferred_suites || !min_keylength) return; preferred_suites = filter(preferred_suites, lambda(int suite) { array(int) def = [array(int)]CIPHER_SUITES[suite]; return def && (CIPHER_effective_keylengths[def[1]] >= min_keylength); }); } #if constant(Crypto.ECC.Curve) && constant(Crypto.AES.GCM) && constant(Crypto.SHA384) //! Configure the context for Suite B compliant operation. //! //! This restricts the context to the cipher suites //! specified by @rfc{6460@} in strict mode. //! //! Additional suites may be enabled, but they will only be //! selected if a Suite B suite isn't available. //! //! @param min_keylength //! Minimum supported key length in bits. Either @expr{128@} //! or @expr{192@}. //! //! @param strictness_level //! Allow additional suites. //! @int //! @value 2.. //! Strict mode. //! //! Allow only the Suite B suites from @rfc{6460@} and TLS 1.2. //! @value 1 //! Transitional mode. //! //! Also allow the transitional suites from @rfc{5430@} for use //! with TLS 1.0 and 1.1. //! @value 0 //! Permissive mode (default). //! //! Also allow other suites that conform to the minimum key length. //! @endint //! //! @note //! This function is only present when Suite B compliant operation //! is possible (ie both elliptic curves and GCM are available). //! //! @note //! Note also that for Suite B server operation compliant certificates //! need to be added with @[add_cert()]. //! //! @seealso //! @[get_suites()] void configure_suite_b(int(128..)|void min_keylength, int(0..)|void strictness_level) { if( !min_keylength ) min_keylength = 256; if (min_keylength!=256) error("Only keylength 256 supported.\n"); preferred_suites = ({ TLS_ecdhe_ecdsa_with_aes_256_gcm_sha384, }); supported_versions = ({ PROTOCOL_TLS_1_2 }); if (strictness_level < 2) { // Transitional or permissive mode. // Allow TLS 1.0. supported_versions = ({ PROTOCOL_TLS_1_2, PROTOCOL_TLS_1_1, PROTOCOL_TLS_1_0, }); // First add the transitional suites. preferred_suites += ({ TLS_ecdhe_ecdsa_with_aes_256_cbc_sha, }); if (strictness_level < 1) { // Permissive mode. Add the remaining suites of // the required strength. preferred_suites += get_suites(min_keylength) - preferred_suites; } } } #endif /* Crypto.ECC.Curve && Crypto.AES.GCM && Crypto.SHA384 */ //! Called by the KeyExchangeExportRSA during KE_rsa_export key //! exchanges to get the weak RSA key. By default a new 512 bit key is //! generated for each key exchange. This method can be overloaded to //! provide caching or alternative means to generate keys. Crypto.RSA get_export_rsa_key() { return Crypto.RSA()->generate_key(512); } // --- PSK API // In addition to implementing get_psk, get_psk_id if you are a client // and optionally get_psk_hint if you are a server, the context object // also needs to ensure the apprioriate PSK cipher suites are in the // preferred_suites array. If the server is only accepting these PSK // connections, simply setting the array to a single member is best. // The client must only include PSK suites when talking to a servers // known to support it, or risk getting MITM attacks. //! A context created for server side PSK use can optionally implement //! get_psk_hint to return a hint string to be sent to the client. If //! not implemented, or returning 0, no PSK hint will be sent. optional string(8bit) get_psk_hint(); //! A context created for client side PSK use must implement a //! get_psk_id method, which will be called with the server provided //! hint, or 0 if no hint was sent. Note that while there is an API //! difference between no hint and a zero length hint, some PSK modes //! are unable to send no hints. //! //! The method should return a key id //! for the PSK, which will be sent to the server. If the hint is not //! valid, 0 should be returned. optional string(8bit) get_psk_id(string(8bit) hint); //! A context created for PSK use must implement a get_psk method, //! which will be called with the key id, and should return the key to //! be used for the connection. If the id is not valid, 0 should be //! returned. optional string(8bit) get_psk(string(8bit) id); // // --- Certificates and authentication // // Unless connecting in anonymous mode the server has to have a set of // CertificatePair certificate chains to sign its handshake with. // These are stored in the cert_chains_domain mapping, where they are // retrieved based on domain the client is connecting to. // // If the server sends a certificate request the client has to respond // with a certificate matching the requested issuer der. These are // stored in the cert_chains_issuer mapping. // // FIXME: Currently only one client certificate per der issuer is // supported. If multiple are added a random one will be selected, // which later may fail when verified against supported certificate // types, hash/signature algorithms. // // FIXME: There is no need to allow the same context object to be used // both for client and server side, so we could join // cert_chains_domain and cert_chains_issuer into one system. // // The client/server potentially has a set of trusted issuers // certificates (root certificates) that are used to validate the // server/client sent certificate. These are stored in trusted_issuers // and in a cache from subject der to Verifier object. FIXME: Should // use key identifier. //! Policy for client authentication. One of //! @[SSL.Constants.AUTHLEVEL_none], //! @[SSL.Constants.AUTHLEVEL_verify], @[SSL.Constants.AUTHLEVEL_ask] //! and @[SSL.Constants.AUTHLEVEL_require]. //! //! Defaults to SSL.Constants.AUTHLEVEL_none. int auth_level = AUTHLEVEL_none; //! Array of authorities that are accepted for client certificates. //! The server will only accept connections from clients whose //! certificate is signed by one of these authorities. The string is a //! DER-encoded certificate, which typically must be decoded using //! @[MIME.decode_base64] or @[Standards.PEM.Messages] first. //! //! Note that it is presumed that the issuer will also be trusted by //! the server. See @[trusted_issuers] for details on specifying //! trusted issuers. //! //! If empty, the server will accept any client certificate whose //! issuer is trusted by the server. void set_authorities(array(string) a) { authorities = a; update_authorities(); } //! Get the list of allowed authorities. See @[set_authorities]. array(string) get_authorities() { return authorities; } protected array(string) authorities = ({}); array(string(8bit)) authorities_cache = ({}); //! Sets the list of trusted certificate issuers. //! //! @param issuers //! //! An array of certificate chains whose root is self signed (ie a //! root issuer), and whose final certificate is an issuer that we //! trust. The root of the certificate should be first certificate in //! the chain. The string is a DER-encoded certificate, which //! typically must be decoded using @[MIME.decode_base64] or //! @[Standards.PEM.Messages] first. //! //! If this array is left empty, and the context is set to verify //! certificates, a certificate chain must have a root that is self //! signed. void set_trusted_issuers(array(array(string(8bit))) issuers) { trusted_issuers = issuers; update_trusted_issuers(); } //! Get the list of trusted issuers. See @[set_trusted_issuers]. array(array(string(8bit))) get_trusted_issuers() { return trusted_issuers; } protected array(array(string(8bit))) trusted_issuers = ({}); //! Mapping from DER-encoded issuer to @[Standards.X509.Verifier]s //! compatible with eg @[Standards.X509.verify_certificate()] and //! @[Standards.X509.load_authorities()]. //! //! @seealso //! @[get_trusted_issuers()], @[set_trusted_issuers()] mapping(string(8bit):array(Standards.X509.Verifier)) trusted_issuers_cache = ([]); //! The possible client authentication methods. Used only if //! auth_level is AUTH_ask or AUTH_require. Generated by //! @[set_authorities]. array(int) client_auth_methods = ({}); // Lookup from issuer DER to an array of suitable @[CertificatePair]s, // sorted in order of strength. protected mapping(string(8bit):array(CertificatePair)) cert_chains_issuer = ([]); // Lookup from DN/SNI domain name/glob to an array of suitable // @[CertificatePair]s, sorted in order of strength. protected mapping(string(8bit):array(CertificatePair)) cert_chains_domain = ([]); //! Look up a suitable set of certificates for the specified issuer. //! @[UNDEFIEND] if no certificate was found. Called only by the //! ClientConnection as a response to a certificate request. array(CertificatePair) find_cert_issuer(array(string) ders) { // Return the first matching issuer. FIXME: Should we merge if // several matching issuers are found? foreach(ders, string der) if(cert_chains_issuer[der]) return cert_chains_issuer[der]; // We MAY return any certificate here. Let's not reveal any // certificates not specifically requested. return UNDEFINED; } //! Look up a suitable set of certificates for the specified domain. //! @[UNDEFINED] if no certificate was found. Called only by the //! Server. array(CertificatePair) find_cert_domain(string(8bit) domain) { if( domain ) { if( cert_chains_domain[domain] ) return cert_chains_domain[domain]; // Return first matching chain that isn't a fallback certificate. foreach(cert_chains_domain; string g; array(CertificatePair) chains) if( (g != "*") && glob(g, domain) ) return chains; } return cert_chains_domain["*"]; } //! Returns a list of all server certificates added with @[add_cert]. array(CertificatePair) get_certificates() { mapping(CertificatePair:int) c = ([]); foreach(cert_chains_domain;; array(CertificatePair) chains) foreach(chains, CertificatePair p) c[p]++; return indices(c); } //! Add a certificate. //! //! This function is used on both servers and clients to add //! a key and chain of certificates to the set of certificate //! candidates to use in @[find_cert()]. //! //! On a server these are used in the normal initial handshake, //! while on a client they are only used if a server requests //! client certificate authentication. //! //! @param key //! Private key matching the first certificate in @[certs]. //! //! Supported key types are currently: //! @mixed //! @type Crypto.RSA.State //! Rivest-Shamir-Adelman. //! @type Crypto.DSA.State //! Digital Signing Algorithm. //! @type Crypto.ECC.Curve.ECDSA //! Elliptic Curve Digital Signing Algorithm. //! @endmixed //! //! This key MUST match the public key in the first certificate //! in @[certs]. //! //! @param certs //! A chain of X509.v1 or X509.v3 certificates, with the local //! certificate first and root-most certificate last. //! //! @param extra_name_globs //! Further SNI globs (than the ones in the first certificate), that //! this certificate should be selected for. Typically used to set //! the default certificate(s) by specifying @expr{({ "*" })@}. //! //! The SNI globs are only relevant for server-side certificates. //! //! @param cp //! An alternative is to send an initialized @[CertificatePair]. //! //! @throws //! The function performs various validations of the @[key] //! and @[certs], and throws errors if the validation fails. //! //! @seealso //! @[find_cert()] void add_cert(Crypto.Sign.State key, array(string(8bit)) certs, array(string(8bit))|void extra_name_globs) { CertificatePair cp = CertificatePair(key, certs, extra_name_globs); add_cert(cp); } variant void add_cert(string(8bit) key, array(string(8bit)) certs, array(string(8bit))|void extra_name_globs) { Crypto.Sign.State _key = Standards.PKCS.RSA.parse_private_key(key) || Standards.PKCS.DSA.parse_private_key(key) || #if constant(Crypto.ECC.Curve) Standards.PKCS.ECDSA.parse_private_key(key) || #endif 0; add_cert(_key, certs, extra_name_globs); } variant void add_cert(CertificatePair cp) { void add(string what, mapping(string:array(CertificatePair)) to) { if( !to[what] ) to[what] = ({cp}); else to[what] = sort( to[what]+({cp}) ); }; // FIXME: Look at leaf flags to determine which mapping to store the // chains in. // Insert cp in cert_chains both under all DN/SNI names/globs and // under issuer DER. Keep lists sorted by strength. foreach( cp->globs, string id ) add(id, cert_chains_domain); add(cp->issuers[0], cert_chains_issuer); } // update the cached decoded authorities list private void update_authorities() { authorities_cache = ({}); mapping(int:int) cert_types = ([]); foreach(authorities, string a) { Standards.X509.TBSCertificate tbs = Standards.X509.decode_certificate(a); Standards.ASN1.Types.Identifier id = [object(Standards.ASN1.Types.Identifier)]tbs->algorithm[0]; // --- START Duplicated code from CertificatePair SignatureScheme sign_alg = [object(SignatureScheme)]pkcs_der_to_sign_alg[id->get_der()]; if (!sign_alg) error("Unknown signature algorithm.\n"); int cert_type = ([ SIGNATURE_rsa: AUTH_rsa_sign, SIGNATURE_dsa: AUTH_dss_sign, SIGNATURE_ecdsa: AUTH_ecdsa_sign, ])[sign_alg & SIGNATURE_MASK]; // --- END Duplicated code from CertificatePair cert_types[cert_type]++; authorities_cache += ({ tbs->subject->get_der() }); } client_auth_methods = indices(cert_types); } // update the cached decoded issuers list private void update_trusted_issuers() { trusted_issuers_cache=([]); foreach(trusted_issuers, array(string) i) { // make sure the chain is valid and intact. mapping result = Standards.X509.verify_certificate_chain(i, ([]), 0); if(!result->verified) error("Broken trusted issuer chain!\n"); // FIXME: The pathLenConstraint does not survive the cache. // The leaf of the trusted issuer is the root to validate // certificate chains against. Standards.X509.TBSCertificate cert = ([array(object(Standards.X509.TBSCertificate))]result->certificates)[-1]; if( !cert->ext_basicConstraints_cA || !(cert->ext_keyUsage & Standards.X509.KU_keyCertSign) ) error("Trusted issuer not allowed to sign other certificates.\n"); trusted_issuers_cache[cert->subject->get_der()] += ({ cert->public_key }); } } // // --- Sessions // //! Non-zero to enable caching of sessions int use_cache = 1; //! Sessions are removed from the cache when they have been inactive //! more than this number of seconds. Sessions are also removed from //! the cache if a connection using the session dies unexpectedly. int session_lifetime = 600; //! Maximum number of sessions to keep in the cache. int max_sessions = 300; mapping(string:Session) session_cache = ([]); // Remove sessions older than @[session_lifetime] from the session cache. void forget_old_sessions() { int t = time() - session_lifetime; foreach(session_cache; string id; Session session) { if(session->last_activity < t) { SSL3_DEBUG_MSG("SSL.Context->forget_old_sessions: " "garbing session %O due to session_lifetime limit\n", id); m_delete (session_cache, id); } } } //! Lookup a session identifier in the cache. Returns the //! corresponding session, or zero if it is not found or caching is //! disabled. Session lookup_session(string id) { if (use_cache) return session_cache[id]; else return 0; } //! Decode a session ticket and return the corresponding session //! if valid or zero if invalid. //! //! @note //! The default implementation just calls @[lookup_session()]. //! //! Override this function (and @[encode_ticket()]) to implement //! server-side state-less session resumption. //! //! @seealso //! @[encode_ticket()], @[lookup_session()] Session decode_ticket(string(8bit) ticket) { return lookup_session(ticket); } //! Generate a session ticket for a session. //! //! @note //! The default implementation just generates a random ticket //! and calls @[record_session()] to store it. //! //! Over-ride this function (and @[decode_ticket()]) to implement //! server-side state-less session resumption. //! //! @returns //! Returns @expr{0@} (zero) on failure (ie cache disabled), and //! an array on success: //! @array //! @elem string(8bit) 0 //! Non-empty string with the ticket. //! @elem int 1 //! Lifetime hint for the ticket. //! @endarray //! //! @seealso //! @[decode_ticket()], @[record_session()], @rfc{4507:3.3@} array(string(8bit)|int) encode_ticket(Session session) { if (!use_cache) return 0; string(8bit) ticket = session->ticket; if (!sizeof(ticket||"")) { do { ticket = random(32); } while(session_cache[ticket]); // FIXME: Should we update the fields here? // Consider moving this to the caller. session->ticket = ticket; session->ticket_expiry_time = time(1) + 3600; } string(8bit) orig_id = session->identity; session->identity = ticket; record_session(session); session->identity = orig_id; // FIXME: Calculate the lifetime from the ticket_expiry_time field? return ({ ticket, 3600 }); } //! Create a new session. Session new_session() { string(8bit) id = ""; if(use_cache) do { id = random(32); } while( session_cache[id] ); Session s = Session(id); s->ffdhe_groups = ffdhe_groups; return s; } //! Add a session to the cache (if caching is enabled). void record_session(Session s) { if (use_cache && sizeof(s->identity||"")) { if( sizeof(session_cache) > max_sessions ) { forget_old_sessions(); int to_delete = sizeof(session_cache)-max_sessions; foreach(session_cache; string id;) { // Randomly delete sessions to keep within the limit. if( to_delete-- < 0 ) break; SSL3_DEBUG_MSG("SSL.Context->record_session: " "garbing session %O due to max_sessions limit\n", id); m_delete (session_cache, id); } } SSL3_DEBUG_MSG("SSL.Context->record_session: caching session %O\n", s->identity); session_cache[s->identity] = s; } } //! Invalidate a session for resumption and remove it from the cache. void purge_session(Session s) { SSL3_DEBUG_MSG("SSL.Context->purge_session: %O\n", s->identity || ""); if (s->identity) m_delete (session_cache, s->identity); /* RFC 4346 7.2: * In this case [fatal alert], other connections corresponding to * the session may continue, but the session identifier MUST be * invalidated, preventing the failed session from being used to * establish new connections. */ s->identity = 0; if (s->version > PROTOCOL_TLS_1_2) { // In TLS 1.2 and earlier the master_secret may be shared // between multiple concurrent connections (cf eg above), // so we can't scratch the master secret. s->master_secret = 0; } } // // --- Compatibility code // //! @decl int verify_certificates //! //! Determines whether certificates presented by the peer are //! verified, or just accepted as being valid. //! //! @deprecated auth_level __deprecated__ void `verify_certificates=(int i) { if(!i) auth_level = AUTHLEVEL_none; else if(auth_level < AUTHLEVEL_verify) auth_level = AUTHLEVEL_verify; } __deprecated__ int `verify_certificates() { return auth_level >= AUTHLEVEL_verify; } //! @decl int require_trust //! //! When set, require the chain to be known, even if the root is self //! signed. //! //! Note that if set, and certificates are set to be verified, trusted //! issuers must be provided, or no connections will be accepted. //! //! @deprecated auth_level __deprecated__ void `require_trust=(int i) { if(i) auth_level = AUTHLEVEL_require; else if(auth_level > AUTHLEVEL_verify) auth_level = AUTHLEVEL_verify; } __deprecated__ int `require_trust() { return auth_level >= AUTHLEVEL_require; } //! @decl int(0..1) encrypt_then_mac //! //! Attempt to enable encrypt-then-mac mode. Defaults to @expr{1@}. //! //! @deprecated extensions __deprecated__ void `encrypt_then_mac=(int(0..1) i) { extensions[EXTENSION_encrypt_then_mac] = !!i; } __deprecated__ int(0..1) `encrypt_then_mac() { return !!extensions[EXTENSION_encrypt_then_mac]; } //! @decl int min_version //! @decl int max_version //! //! The accepted range of versions for the client/server. List //! specific versions in @[supported_versions] instead. //! //! @deprecated supported_versions ProtocolVersion `min_version() { return min(@supported_versions); } ProtocolVersion `max_version() { return max(@supported_versions); } protected void generate_versions(ProtocolVersion min, ProtocolVersion max) { supported_versions = [array(int(16bit))]reverse(enumerate([int(16bit)](max-min+1), 1, min)); } void `min_version=(ProtocolVersion version) { ProtocolVersion m = max_version; if( version > m ) supported_versions = ({ version }); else generate_versions(version, m); } void `max_version=(ProtocolVersion version) { ProtocolVersion m = min_version; if( version < m ) supported_versions = ({ version }); else generate_versions(m, version); }

pike.git/ lib/ modules/ SSL.pmod/ Context.pike > edb6e9ce062f8fdd61b468bf72506bb7c6e160bd [Annotate]