/* * ZeroTier One - Global Peer to Peer Ethernet * Copyright (C) 2012-2013 ZeroTier Networks LLC * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . * * -- * * ZeroTier may be used and distributed under the terms of the GPLv3, which * are available at: http://www.gnu.org/licenses/gpl-3.0.html * * If you would like to embed ZeroTier into a commercial application or * redistribute it in a modified binary form, please contact ZeroTier Networks * LLC. Start here: http://www.zerotier.com/ */ #ifndef ZT_CONSTANTS_HPP #define ZT_CONSTANTS_HPP // // This include file also auto-detects and canonicalizes some environment // information defines: // // __LINUX__ // __APPLE__ // __UNIX_LIKE__ - any "unix like" OS (BSD, posix, etc.) // __WINDOWS__ // // Also makes sure __BYTE_ORDER is defined reasonably. // // Canonicalize Linux... is this necessary? Do it anyway to be defensive. #if defined(__linux__) || defined(linux) || defined(__LINUX__) || defined(__linux) #ifndef __LINUX__ #define __LINUX__ #ifndef __UNIX_LIKE__ #define __UNIX_LIKE__ #endif #endif #endif // TODO: Android is what? Linux technically, but does it define it? // OSX and iOS are unix-like OSes far as we're concerned #ifdef __APPLE__ #include #ifndef __UNIX_LIKE__ #define __UNIX_LIKE__ #endif #endif // Linux has endian.h #ifdef __LINUX__ #include #endif #if defined(_WIN32) || defined(_WIN64) #ifndef __WINDOWS__ #define __WINDOWS__ #endif #define NOMINMAX #pragma warning(disable : 4290) #pragma warning(disable : 4996) #pragma warning(disable : 4101) #undef __UNIX_LIKE__ #define ZT_PATH_SEPARATOR '\\' #define ZT_PATH_SEPARATOR_S "\\" #define ZT_EOL_S "\r\n" #endif // Assume these are little-endian. PPC is not supported for OSX, and ARM // runs in little-endian mode for these OS families. #if defined(__APPLE__) || defined(__WINDOWS__) #undef __BYTE_ORDER #undef __LITTLE_ENDIAN #undef __BIG_ENDIAN #define __BIG_ENDIAN 4321 #define __LITTLE_ENDIAN 1234 #define __BYTE_ORDER 1234 #endif #ifdef __UNIX_LIKE__ #define ZT_PATH_SEPARATOR '/' #define ZT_PATH_SEPARATOR_S "/" #define ZT_EOL_S "\n" #endif // Error out if required symbols are missing #ifndef __BYTE_ORDER error_no_byte_order_defined; #endif /** * Length of a ZeroTier address in bytes */ #define ZT_ADDRESS_LENGTH 5 /** * Addresses beginning with this byte are reserved for the joy of in-band signaling */ #define ZT_ADDRESS_RESERVED_PREFIX 0xff /** * Default local UDP port */ #define ZT_DEFAULT_UDP_PORT 9993 /** * Local control port, also used for multiple invocation check */ #define ZT_DEFAULT_CONTROL_UDP_PORT 39393 /** * Default payload MTU for UDP packets * * In the future we might support UDP path MTU discovery, but for now we * set a maximum that is equal to 1500 minus 8 (for PPPoE overhead, common * in some markets) minus 48 (IPv6 UDP overhead). */ #define ZT_UDP_DEFAULT_PAYLOAD_MTU 1444 /** * MTU used for Ethernet tap device * * This is pretty much an unchangeable global constant. To make it change * across nodes would require logic to send ICMP packet too big messages, * which would complicate things. 1500 has been good enough on most LANs * for ages, so a larger MTU should be fine for the forseeable future. This * typically results in two UDP packets per single large frame. Experimental * results seem to show that this is good. Larger MTUs resulting in more * fragments seemed too brittle on slow/crummy links for no benefit. * * If this does change, also change it in tap.h in the tuntaposx code under * mac-tap. * * Overhead for a normal frame split into two packets: * * 1414 = 1444 (typical UDP MTU) - 28 (packet header) - 2 (ethertype) * 1428 = 1444 (typical UDP MTU) - 16 (fragment header) * SUM: 2842 * * We use 2800, which leaves some room for other payload in other types of * messages such as multicast propagation or future support for bridging. */ #define ZT_IF_MTU 2800 /** * Maximum number of packet fragments we'll support * * The actual spec allows 16, but this is the most we'll support right * now. Packets with more than this many fragments are dropped. */ #define ZT_MAX_PACKET_FRAGMENTS 3 /** * Timeout for receipt of fragmented packets in ms * * Since there's no retransmits, this is just a really bad case scenario for * transit time. It's short enough that a DOS attack from exhausing buffers is * very unlikely, as the transfer rate would have to be fast enough to fill * system memory in this time. */ #define ZT_FRAGMENTED_PACKET_RECEIVE_TIMEOUT 1000 /** * First byte of MAC addresses derived from ZeroTier addresses * * This has the 0x02 bit set, which indicates a locally administrered * MAC address rather than one with a known HW ID. */ #define ZT_MAC_FIRST_OCTET 0x32 /** * Length of secret key in bytes */ #define ZT_PEER_SECRET_KEY_LENGTH 32 /** * How often Topology::clean() and Network::clean() are called in ms */ #define ZT_DB_CLEAN_PERIOD 300000 /** * How long to remember peers in RAM if they haven't been used */ #define ZT_PEER_IN_MEMORY_EXPIRATION 600000 /** * Delay between WHOIS retries in ms */ #define ZT_WHOIS_RETRY_DELAY 350 /** * Maximum identity WHOIS retries */ #define ZT_MAX_WHOIS_RETRIES 3 /** * Transmit queue entry timeout */ #define ZT_TRANSMIT_QUEUE_TIMEOUT (ZT_WHOIS_RETRY_DELAY * (ZT_MAX_WHOIS_RETRIES + 1)) /** * Receive queue entry timeout */ #define ZT_RECEIVE_QUEUE_TIMEOUT (ZT_WHOIS_RETRY_DELAY * (ZT_MAX_WHOIS_RETRIES + 1)) /** * Maximum number of ZT hops allowed * * The protocol allows up to 7, but we limit it to something smaller. */ #define ZT_RELAY_MAX_HOPS 3 /** * Size of multicast deduplication ring buffer in 64-bit ints */ #define ZT_MULTICAST_DEDUP_HISTORY_LENGTH 512 /** * Default number of bits in multicast propagation prefix */ #define ZT_DEFAULT_MULTICAST_PREFIX_BITS 1 /** * Default max depth (TTL) for multicast propagation */ #define ZT_DEFAULT_MULTICAST_DEPTH 32 /** * Global maximum for multicast propagation depth * * This is kind of an insane value, meant as a sanity check. */ #define ZT_MULTICAST_GLOBAL_MAX_DEPTH 500 /** * Expire time for multicast 'likes' in ms */ #define ZT_MULTICAST_LIKE_EXPIRE 120000 /** * Time between polls of local taps for multicast membership changes */ #define ZT_MULTICAST_LOCAL_POLL_PERIOD 10000 /** * Delay between scans of the topology active peer DB for peers that need ping */ #define ZT_PING_CHECK_DELAY 7000 /** * Delay between checks of network configuration fingerprint */ #define ZT_NETWORK_FINGERPRINT_CHECK_DELAY 5000 /** * Delay between pings (actually HELLOs) to direct links */ #define ZT_PEER_DIRECT_PING_DELAY 120000 /** * Delay in ms between firewall opener packets to direct links * * This should be lower than the UDP conversation entry timeout in most * stateful firewalls. */ #define ZT_FIREWALL_OPENER_DELAY 50000 /** * Delay between requests for updated network autoconf information */ #define ZT_NETWORK_AUTOCONF_DELAY 60000 /** * Delay in core loop between checks of network autoconf newness */ #define ZT_NETWORK_AUTOCONF_CHECK_DELAY 7000 /** * Minimum delay in Node service loop * * This is the shortest of the check delays/periods. */ #define ZT_MIN_SERVICE_LOOP_INTERVAL ZT_NETWORK_FINGERPRINT_CHECK_DELAY /** * Activity timeout for links * * A link that hasn't spoken in this long is simply considered inactive. */ #define ZT_PEER_LINK_ACTIVITY_TIMEOUT ((ZT_PEER_DIRECT_PING_DELAY * 2) + 1000) /** * Number of outgoing verb/packetId pairs to keep for sends expecting responses */ #define ZT_PEER_REQUEST_HISTORY_LENGTH 8 /** * IP hops (a.k.a. TTL) to set for firewall opener packets * * 2 should permit traversal of double-NAT configurations, such as from inside * a VM running behind local NAT on a host that is itself behind NAT. */ #define ZT_FIREWALL_OPENER_HOPS 2 /** * Delay sleep overshoot for detection of a probable sleep/wake event */ #define ZT_SLEEP_WAKE_DETECTION_THRESHOLD 2000 /** * Time to pause main service loop after sleep/wake detect */ #define ZT_SLEEP_WAKE_SETTLE_TIME 5000 /** * Minimum interval between attempts by relays to unite peers */ #define ZT_MIN_UNITE_INTERVAL 30000 /** * Delay in milliseconds between firewall opener and real packet for NAT-t */ #define ZT_RENDEZVOUS_NAT_T_DELAY 500 /** * Minimum interval between attempts to do a software update */ #define ZT_UPDATE_MIN_INTERVAL 120000 /** * Maximum interval between attempts to do a software update */ #define ZT_UPDATE_MAX_INTERVAL 28800000 /** * Update HTTP timeout in seconds */ #define ZT_UPDATE_HTTP_TIMEOUT 30 #endif