ZeroTierOne/node/Constants.hpp

389 lines
10 KiB
C++

/*
* ZeroTier One - Network Virtualization Everywhere
* Copyright (C) 2011-2016 ZeroTier, Inc. https://www.zerotier.com/
*
* 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 <http://www.gnu.org/licenses/>.
*/
#ifndef ZT_CONSTANTS_HPP
#define ZT_CONSTANTS_HPP
#include "../include/ZeroTierOne.h"
//
// This include file also auto-detects and canonicalizes some environment
// information defines:
//
// __LINUX__
// __APPLE__
// __BSD__ (OSX also defines this)
// __UNIX_LIKE__ (Linux, BSD, etc.)
// __WINDOWS__
//
// Also makes sure __BYTE_ORDER is defined reasonably.
//
// Hack: make sure __GCC__ is defined on old GCC compilers
#ifndef __GCC__
#if defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_1) || defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_2) || defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4)
#define __GCC__
#endif
#endif
#if defined(__linux__) || defined(linux) || defined(__LINUX__) || defined(__linux)
#ifndef __LINUX__
#define __LINUX__
#endif
#ifndef __UNIX_LIKE__
#define __UNIX_LIKE__
#endif
#include <endian.h>
#endif
#ifdef __APPLE__
#include <TargetConditionals.h>
#ifndef __UNIX_LIKE__
#define __UNIX_LIKE__
#endif
#ifndef __BSD__
#define __BSD__
#endif
#include <machine/endian.h>
#endif
// Defined this macro to disable "type punning" on a number of targets that
// have issues with unaligned memory access.
#if defined(__arm__) || defined(__ARMEL__) || (defined(__APPLE__) && ( (defined(TARGET_OS_IPHONE) && (TARGET_OS_IPHONE != 0)) || (defined(TARGET_OS_WATCH) && (TARGET_OS_WATCH != 0)) || (defined(TARGET_IPHONE_SIMULATOR) && (TARGET_IPHONE_SIMULATOR != 0)) ) )
#ifndef ZT_NO_TYPE_PUNNING
#define ZT_NO_TYPE_PUNNING
#endif
#endif
#if defined(__FreeBSD__) || defined(__OpenBSD__)
#ifndef __UNIX_LIKE__
#define __UNIX_LIKE__
#endif
#ifndef __BSD__
#define __BSD__
#endif
#include <machine/endian.h>
#ifndef __BYTE_ORDER
#define __BYTE_ORDER _BYTE_ORDER
#define __LITTLE_ENDIAN _LITTLE_ENDIAN
#define __BIG_ENDIAN _BIG_ENDIAN
#endif
#endif
#if defined(_WIN32) || defined(_WIN64)
#ifndef __WINDOWS__
#define __WINDOWS__
#endif
#ifndef NOMINMAX
#define NOMINMAX
#endif
#pragma warning(disable : 4290)
#pragma warning(disable : 4996)
#pragma warning(disable : 4101)
#undef __UNIX_LIKE__
#undef __BSD__
#define ZT_PATH_SEPARATOR '\\'
#define ZT_PATH_SEPARATOR_S "\\"
#define ZT_EOL_S "\r\n"
#include <WinSock2.h>
#include <Windows.h>
#endif
// Assume little endian if not defined
#if (defined(__APPLE__) || defined(__WINDOWS__)) && (!defined(__BYTE_ORDER))
#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
#ifndef __BYTE_ORDER
#include <endian.h>
#endif
/**
* Length of a ZeroTier address in bytes
*/
#define ZT_ADDRESS_LENGTH 5
/**
* Length of a hexadecimal ZeroTier address
*/
#define ZT_ADDRESS_LENGTH_HEX 10
/**
* Addresses beginning with this byte are reserved for the joy of in-band signaling
*/
#define ZT_ADDRESS_RESERVED_PREFIX 0xff
/**
* 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
/**
* Default MTU used for Ethernet tap device
*/
#define ZT_IF_MTU ZT_MAX_MTU
/**
* 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 4
/**
* Size of RX queue
*
* This is about 2mb, and can be decreased for small devices. A queue smaller
* than about 4 is probably going to cause a lot of lost packets.
*/
#define ZT_RX_QUEUE_SIZE 64
/**
* RX queue entries older than this do not "exist"
*/
#define ZT_RX_QUEUE_EXPIRE 4000
/**
* Length of secret key in bytes -- 256-bit -- do not change
*/
#define ZT_PEER_SECRET_KEY_LENGTH 32
/**
* How often Topology::clean() and Network::clean() and similar are called, in ms
*/
#define ZT_HOUSEKEEPING_PERIOD 120000
/**
* Overriding granularity for timer tasks to prevent CPU-intensive thrashing on every packet
*/
#define ZT_CORE_TIMER_TASK_GRANULARITY 500
/**
* How long to remember peer records 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 1000
/**
* Maximum identity WHOIS retries (each attempt tries consulting a different peer)
*/
#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 (this is not IP hops/TTL)
*
* The protocol allows up to 7, but we limit it to something smaller.
*/
#define ZT_RELAY_MAX_HOPS 3
/**
* Expire time for multicast 'likes' and indirect multicast memberships in ms
*/
#define ZT_MULTICAST_LIKE_EXPIRE 600000
/**
* Delay between explicit MULTICAST_GATHER requests for a given multicast channel
*/
#define ZT_MULTICAST_EXPLICIT_GATHER_DELAY (ZT_MULTICAST_LIKE_EXPIRE / 10)
/**
* Timeout for outgoing multicasts
*
* This is how long we wait for explicit or implicit gather results.
*/
#define ZT_MULTICAST_TRANSMIT_TIMEOUT 5000
/**
* Default maximum number of peers to address with a single multicast (if unspecified in network config)
*/
#define ZT_MULTICAST_DEFAULT_LIMIT 32
/**
* How frequently to send a zero-byte UDP keepalive packet
*
* There are NATs with timeouts as short as 20 seconds, so this turns out
* to be needed.
*/
#define ZT_NAT_KEEPALIVE_DELAY 19000
/**
* Delay between scans of the topology active peer DB for peers that need ping
*
* This is also how often pings will be retried to upstream peers (relays, roots)
* constantly until something is heard.
*/
#define ZT_PING_CHECK_INVERVAL 9500
/**
* Delay between ordinary case pings of direct links
*/
#define ZT_PEER_DIRECT_PING_DELAY 60000
/**
* Timeout for overall peer activity (measured from last receive)
*/
#define ZT_PEER_ACTIVITY_TIMEOUT 500000
/**
* Timeout for path activity
*/
#define ZT_PATH_ACTIVITY_TIMEOUT ZT_PEER_ACTIVITY_TIMEOUT
/**
* No answer timeout to trigger dead path detection
*/
#define ZT_PEER_DEAD_PATH_DETECTION_NO_ANSWER_TIMEOUT 2500
/**
* Probation threshold after which a path becomes dead
*/
#define ZT_PEER_DEAD_PATH_DETECTION_MAX_PROBATION 3
/**
* Delay between requests for updated network autoconf information
*/
#define ZT_NETWORK_AUTOCONF_DELAY 60000
/**
* Minimum interval between attempts by relays to unite peers
*
* When a relay gets a packet destined for another peer, it sends both peers
* a RENDEZVOUS message no more than this often. This instructs the peers
* to attempt NAT-t and gives each the other's corresponding IP:port pair.
*/
#define ZT_MIN_UNITE_INTERVAL 30000
/**
* Delay between initial direct NAT-t packet and more aggressive techniques
*
* This may also be a delay before sending the first packet if we determine
* that we should wait for the remote to initiate rendezvous first.
*/
#define ZT_NAT_T_TACTICAL_ESCALATION_DELAY 1000
/**
* How long (max) to remember network certificates of membership?
*
* This only applies to networks we don't belong to.
*/
#define ZT_PEER_NETWORK_COM_EXPIRATION 3600000
/**
* Sanity limit on maximum bridge routes
*
* If the number of bridge routes exceeds this, we cull routes from the
* bridges with the most MACs behind them until it doesn't. This is a
* sanity limit to prevent memory-filling DOS attacks, nothing more. No
* physical LAN has anywhere even close to this many nodes. Note that this
* does not limit the size of ZT virtual LANs, only bridge routing.
*/
#define ZT_MAX_BRIDGE_ROUTES 67108864
/**
* If there is no known route, spam to up to this many active bridges
*/
#define ZT_MAX_BRIDGE_SPAM 16
/**
* Interval between direct path pushes in milliseconds
*/
#define ZT_DIRECT_PATH_PUSH_INTERVAL 120000
/**
* Time horizon for push direct paths cutoff
*/
#define ZT_PUSH_DIRECT_PATHS_CUTOFF_TIME 60000
/**
* Maximum number of direct path pushes within cutoff time
*
* This limits response to PUSH_DIRECT_PATHS to CUTOFF_LIMIT responses
* per CUTOFF_TIME milliseconds per peer to prevent this from being
* useful for DOS amplification attacks.
*/
#define ZT_PUSH_DIRECT_PATHS_CUTOFF_LIMIT 5
/**
* Maximum number of paths per IP scope (e.g. global, link-local) and family (e.g. v4/v6)
*/
#define ZT_PUSH_DIRECT_PATHS_MAX_PER_SCOPE_AND_FAMILY 4
/**
* A test pseudo-network-ID that can be joined
*
* Joining this network ID will result in a network with no IP addressing
* and default parameters. No network configuration master will be consulted
* and instead a static config will be used. This is used in built-in testnet
* scenarios and can also be used for external testing.
*
* This is an impossible real network ID since 0xff is a reserved address
* prefix.
*/
#define ZT_TEST_NETWORK_ID 0xffffffffffffffffULL
/**
* Desired buffer size for UDP sockets (used in service and osdep but defined here)
*/
#if (defined(__amd64) || defined(__amd64__) || defined(__x86_64) || defined(__x86_64__) || defined(__AMD64) || defined(__AMD64__))
#define ZT_UDP_DESIRED_BUF_SIZE 1048576
#else
#define ZT_UDP_DESIRED_BUF_SIZE 131072
#endif
/* Ethernet frame types that might be relevant to us */
#define ZT_ETHERTYPE_IPV4 0x0800
#define ZT_ETHERTYPE_ARP 0x0806
#define ZT_ETHERTYPE_RARP 0x8035
#define ZT_ETHERTYPE_ATALK 0x809b
#define ZT_ETHERTYPE_AARP 0x80f3
#define ZT_ETHERTYPE_IPX_A 0x8137
#define ZT_ETHERTYPE_IPX_B 0x8138
#define ZT_ETHERTYPE_IPV6 0x86dd
#endif