/* * Copyright (c)2013-2020 ZeroTier, Inc. * * Use of this software is governed by the Business Source License included * in the LICENSE.TXT file in the project's root directory. * * Change Date: 2025-01-01 * * On the date above, in accordance with the Business Source License, use * of this software will be governed by version 2.0 of the Apache License. */ /****/ #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. // #ifndef ZT_INLINE #define ZT_INLINE inline #endif #define restrict // 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 #endif #ifdef __APPLE__ #define likely(x) __builtin_expect((x),1) #define unlikely(x) __builtin_expect((x),0) #include #ifndef __UNIX_LIKE__ #define __UNIX_LIKE__ #endif #ifndef __BSD__ #define __BSD__ #endif #include #endif #if defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__NetBSD__) #ifndef __UNIX_LIKE__ #define __UNIX_LIKE__ #endif #ifndef __BSD__ #define __BSD__ #endif #include #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__ #include #include #endif #ifdef __NetBSD__ #ifndef RTF_MULTICAST #define RTF_MULTICAST 0x20000000 #endif #endif #if (defined(__amd64) || defined(__amd64__) || defined(__x86_64) || defined(__x86_64__) || defined(__AMD64) || defined(__AMD64__) || defined(_M_X64)) #define ZT_ARCH_X64 1 #include #include #include #endif #if (defined(__ARM_NEON) || defined(__ARM_NEON__) || defined(ZT_ARCH_ARM_HAS_NEON)) #if (defined(__APPLE__) && !defined(__LP64__)) || (defined(__ANDROID__) && defined(__arm__)) #ifdef ZT_ARCH_ARM_HAS_NEON #undef ZT_ARCH_ARM_HAS_NEON #endif #else #ifndef ZT_ARCH_ARM_HAS_NEON #define ZT_ARCH_ARM_HAS_NEON 1 #endif #include /*#include */ #endif #endif // Define ZT_NO_TYPE_PUNNING to disable reckless casts on anything other than x86/x64. #if (!(defined(__amd64__) || defined(__amd64) || defined(__x86_64__) || defined(__x86_64) || defined(_M_AMD64) || defined(_M_X64) || defined(i386) || defined(__i386) || defined(__i386__) || defined(__i486__) || defined(__i586__) || defined(__i686__) || defined(_M_IX86) || defined(__X86__) || defined(_X86_) || defined(__I86__) || defined(__INTEL__) || defined(__386))) #ifndef ZT_NO_TYPE_PUNNING #define ZT_NO_TYPE_PUNNING 1 #endif #endif #ifdef ZT_NO_TYPE_PUNNING #ifndef ZT_NO_UNALIGNED_ACCESS #define ZT_NO_UNALIGNED_ACCESS 1 #endif #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 __WINDOWS__ #define ZT_PATH_SEPARATOR '\\' #define ZT_PATH_SEPARATOR_S "\\" #define ZT_EOL_S "\r\n" #else #define ZT_PATH_SEPARATOR '/' #define ZT_PATH_SEPARATOR_S "/" #define ZT_EOL_S "\n" #endif #ifndef __BYTE_ORDER #include #endif #if (defined(__GNUC__) && (__GNUC__ >= 3)) || (defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 800)) || defined(__clang__) #ifndef likely #define likely(x) __builtin_expect((x),1) #endif #ifndef unlikely #define unlikely(x) __builtin_expect((x),0) #endif #else #ifndef likely #define likely(x) (x) #endif #ifndef unlikely #define unlikely(x) (x) #endif #endif #ifdef __WINDOWS__ #define ZT_PACKED_STRUCT(D) __pragma(pack(push,1)) D __pragma(pack(pop)) #else #define ZT_PACKED_STRUCT(D) D __attribute__((packed)) #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 /** * Size of symmetric key (only the first 32 bits are used for some ciphers) */ #define ZT_SYMMETRIC_KEY_SIZE 48 /** * Addresses beginning with this byte are reserved for the joy of in-band signaling */ #define ZT_ADDRESS_RESERVED_PREFIX 0xff /** * Default MTU used for Ethernet tap device */ #define ZT_DEFAULT_MTU 2800 /** * Maximum number of packet fragments we'll support (protocol max: 16) */ #define ZT_MAX_PACKET_FRAGMENTS 7 /** * Size of RX queue */ #define ZT_RX_QUEUE_SIZE 32 /** * Size of TX queue */ #define ZT_TX_QUEUE_SIZE 32 /** * Minimum delay between timer task checks to prevent thrashing */ #define ZT_CORE_TIMER_TASK_GRANULARITY 60 /** * How often Topology::clean() and Network::clean() and similar are called, in ms */ #define ZT_HOUSEKEEPING_PERIOD 30000 /** * Delay between WHOIS retries in ms */ #define ZT_WHOIS_RETRY_DELAY 500 /** * Transmit queue entry timeout */ #define ZT_TRANSMIT_QUEUE_TIMEOUT 5000 /** * Receive queue entry timeout */ #define ZT_RECEIVE_QUEUE_TIMEOUT 5000 /** * 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 /** * Period for multicast LIKE announcements */ #define ZT_MULTICAST_ANNOUNCE_PERIOD 60000 /** * 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 /** * Delay between checks of peer pings, etc., and also related housekeeping tasks */ #define ZT_PING_CHECK_INVERVAL 5000 /** * How often the local.conf file is checked for changes (service, should be moved there) */ #define ZT_LOCAL_CONF_FILE_CHECK_INTERVAL 10000 /** * How frequently to send heartbeats over in-use paths */ #define ZT_PATH_HEARTBEAT_PERIOD 14000 /** * Do not accept HELLOs over a given path more often than this */ #define ZT_PATH_HELLO_RATE_LIMIT 1000 /** * Delay between full-fledge pings of directly connected peers */ #define ZT_PEER_PING_PERIOD 60000 /** * Paths are considered expired if they have not sent us a real packet in this long */ #define ZT_PEER_PATH_EXPIRATION ((ZT_PEER_PING_PERIOD * 4) + 3000) /** * How often to retry expired paths that we're still remembering */ #define ZT_PEER_EXPIRED_PATH_TRIAL_PERIOD (ZT_PEER_PING_PERIOD * 10) /** * Outgoing packets are only used for QoS/ACK statistical sampling if their * packet ID is divisible by this integer. This is to provide a mechanism for * both peers to agree on which packets need special treatment without having * to exchange information. Changing this value would be a breaking change and * would necessitate a protocol version upgrade. Since each incoming and * outgoing packet ID is checked against this value its evaluation is of the * form: * * (id & (divisor - 1)) == 0, thus the divisor must be a power of 2. * * This value is set at (16) so that given a normally-distributed RNG output * we will sample 1/16th (or ~6.25%) of packets. */ #define ZT_QOS_ACK_DIVISOR 0x2 /** * Time horizon for VERB_QOS_MEASUREMENT and VERB_ACK packet processing cutoff */ #define ZT_QOS_ACK_CUTOFF_TIME 30000 /** * Maximum number of VERB_QOS_MEASUREMENT and VERB_ACK packets allowed to be * processed within cutoff time. Separate totals are kept for each type but * the limit is the same for both. * * This limits how often this peer will compute statistical estimates * of various QoS measures from a VERB_QOS_MEASUREMENT or VERB_ACK packets to * CUTOFF_LIMIT times per CUTOFF_TIME milliseconds per peer to prevent * this from being useful for DOS amplification attacks. */ #define ZT_QOS_ACK_CUTOFF_LIMIT 128 /** * Minimum acceptable size for a VERB_QOS_MEASUREMENT packet */ #define ZT_QOS_MIN_PACKET_SIZE (8 + 1) /** * Maximum acceptable size for a VERB_QOS_MEASUREMENT packet */ #define ZT_QOS_MAX_PACKET_SIZE 1400 /** * How many ID:sojourn time pairs are in a single QoS packet */ #define ZT_QOS_TABLE_SIZE ((ZT_QOS_MAX_PACKET_SIZE * 8) / (64 + 16)) /** * Maximum number of outgoing packets we monitor for QoS information */ #define ZT_QOS_MAX_OUTSTANDING_RECORDS (1024 * 16) /** * Interval used for rate-limiting the computation of path quality estimates. */ #define ZT_QOS_COMPUTE_INTERVAL 1000 /** * Number of samples to consider when processing real-time path statistics */ #define ZT_QOS_SHORTTERM_SAMPLE_WIN_SIZE 32 /** * Max allowable time spent in any queue (in ms) */ #define ZT_AQM_TARGET 5 /** * Time period where the time spent in the queue by a packet should fall below. * target at least once. (in ms) */ #define ZT_AQM_INTERVAL 100 /** * The number of bytes that each queue is allowed to send during each DRR cycle. * This approximates a single-byte-based fairness queuing scheme. */ #define ZT_AQM_QUANTUM ZT_DEFAULT_MTU /** * The maximum total number of packets that can be queued among all * active/inactive, old/new queues. */ #define ZT_AQM_MAX_ENQUEUED_PACKETS 1024 /** * Number of QoS queues (buckets) */ #define ZT_AQM_NUM_BUCKETS 9 /** * All unspecified traffic is put in this bucket. Anything in a bucket with a * smaller value is de-prioritized. Anything in a bucket with a higher value is prioritized over other traffic. */ #define ZT_AQM_DEFAULT_BUCKET 0 /** * Timeout for overall peer activity (measured from last receive) */ #ifndef ZT_SDK #define ZT_PEER_ACTIVITY_TIMEOUT 500000 #else #define ZT_PEER_ACTIVITY_TIMEOUT 30000 #endif /** * General rate limit timeout for multiple packet types (HELLO, etc.) */ #define ZT_PEER_GENERAL_INBOUND_RATE_LIMIT 500 /** * General limit for max RTT for requests over the network */ #define ZT_GENERAL_RTT_LIMIT 5000 /** * Delay between requests for updated network autoconf information * * Don't lengthen this as it affects things like QoS / uptime monitoring * via ZeroTier Central. This is the heartbeat, basically. */ #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 /** * How often should peers try memorized or statically defined paths? */ #define ZT_TRY_MEMORIZED_PATH_INTERVAL 30000 /** * 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 L2 bridging route, spam to up to this many active bridges */ #define ZT_MAX_BRIDGE_SPAM 32 /** * Interval between direct path pushes in milliseconds */ #define ZT_DIRECT_PATH_PUSH_INTERVAL 15000 /** * Interval between direct path pushes in milliseconds if we already have a path */ #define ZT_DIRECT_PATH_PUSH_INTERVAL_HAVEPATH 120000 /** * Time horizon for push direct paths cutoff */ #define ZT_PUSH_DIRECT_PATHS_CUTOFF_TIME 30000 /** * Drainage constants for VERB_ECHO rate-limiters */ #define ZT_ECHO_CUTOFF_LIMIT ((1000 / ZT_CORE_TIMER_TASK_GRANULARITY) * ZT_MAX_PEER_NETWORK_PATHS) #define ZT_ECHO_DRAINAGE_DIVISOR (1000 / ZT_ECHO_CUTOFF_LIMIT) /** * Drainage constants for VERB_QOS rate-limiters */ #define ZT_QOS_CUTOFF_LIMIT ((1000 / ZT_CORE_TIMER_TASK_GRANULARITY) * ZT_MAX_PEER_NETWORK_PATHS) #define ZT_QOS_DRAINAGE_DIVISOR (1000 / ZT_QOS_CUTOFF_LIMIT) /** * Drainage constants for VERB_ACK rate-limiters */ #define ZT_ACK_CUTOFF_LIMIT 128 #define ZT_ACK_DRAINAGE_DIVISOR (1000 / ZT_ACK_CUTOFF_LIMIT) #define ZT_BOND_DEFAULT_REFRCTORY_PERIOD 8000 #define ZT_BOND_MAX_REFRACTORY_PERIOD 600000 /** * 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 8 /** * 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 8 /** * Time horizon for VERB_NETWORK_CREDENTIALS cutoff */ #define ZT_PEER_CREDENTIALS_CUTOFF_TIME 60000 /** * Maximum number of VERB_NETWORK_CREDENTIALS within cutoff time */ #define ZT_PEER_CREDEITIALS_CUTOFF_LIMIT 15 /** * WHOIS rate limit (we allow these to be pretty fast) */ #define ZT_PEER_WHOIS_RATE_LIMIT 100 /** * General rate limit for other kinds of rate-limited packets (HELLO, credential request, etc.) both inbound and outbound */ #define ZT_PEER_GENERAL_RATE_LIMIT 1000 /** * Minimum allowed amount of time between flow/path optimizations (anti-flapping) */ #define ZT_BOND_OPTIMIZE_INTERVAL 15000 /** * Maximum number of flows allowed before we start forcibly forgetting old ones */ #define ZT_FLOW_MAX_COUNT (1024 * 64) /** * How often we emit a bond summary for each bond */ #define ZT_BOND_STATUS_INTERVAL 30000 /** * How long before we consider a path to be dead in the general sense. This is * used while searching for default or alternative paths to try in the absence * of direct guidance from the user or a selection policy. */ #define ZT_BOND_FAILOVER_DEFAULT_INTERVAL 5000 /** * Anything below this value gets into thrashing territory since we divide * this value by ZT_BOND_ECHOS_PER_FAILOVER_INTERVAL to send ECHOs often. */ #define ZT_BOND_FAILOVER_MIN_INTERVAL 250 /** * How many times per failover interval that an ECHO is sent. This should be * at least 2. Anything more then 4 starts to increase overhead significantly. */ #define ZT_BOND_ECHOS_PER_FAILOVER_INTERVAL 4 /** * A defensive timer to prevent path quality metrics from being * processed too often. */ #define ZT_BOND_BACKGROUND_TASK_MIN_INTERVAL ZT_CORE_TIMER_TASK_GRANULARITY /** * How often a bonding policy's background tasks are processed, * some need more frequent attention than others. */ #define ZT_BOND_ACTIVE_BACKUP_CHECK_INTERVAL ZT_CORE_TIMER_TASK_GRANULARITY /** * Time horizon for path negotiation paths cutoff */ #define ZT_PATH_NEGOTIATION_CUTOFF_TIME 60000 /** * Maximum number of path negotiations within cutoff time * * This limits response to PATH_NEGOTIATION to CUTOFF_LIMIT responses * per CUTOFF_TIME milliseconds per peer to prevent this from being * useful for DOS amplification attacks. */ #define ZT_PATH_NEGOTIATION_CUTOFF_LIMIT 8 /** * How many times a peer will attempt to petition another peer to synchronize its * traffic to the same path before giving up and surrendering to the other peer's preference. */ #define ZT_PATH_NEGOTIATION_TRY_COUNT 3 /** * How much greater the quality of a path should be before an * optimization procedure triggers a switch. */ #define ZT_BOND_ACTIVE_BACKUP_OPTIMIZE_MIN_THRESHOLD 0.10 /** * Artificially inflates the failover score for paths which meet * certain non-performance-related policy ranking criteria. */ #define ZT_BOND_FAILOVER_HANDICAP_PREFERRED 500 #define ZT_BOND_FAILOVER_HANDICAP_PRIMARY 1000 #define ZT_BOND_FAILOVER_HANDICAP_NEGOTIATED 5000 /** * An indicator that no flow is to be associated with the given packet */ #define ZT_QOS_NO_FLOW -1 /** * Don't do expensive identity validation more often than this * * IPv4 and IPv6 address prefixes are hashed down to 14-bit (0-16383) integers * using the first 24 bits for IPv4 or the first 48 bits for IPv6. These are * then rate limited to one identity validation per this often milliseconds. */ #if (defined(__amd64) || defined(__amd64__) || defined(__x86_64) || defined(__x86_64__) || defined(__AMD64) || defined(__AMD64__) || defined(_M_X64) || defined(_M_AMD64)) // AMD64 machines can do anywhere from one every 50ms to one every 10ms. This provides plenty of margin. #define ZT_IDENTITY_VALIDATION_SOURCE_RATE_LIMIT 2000 #else #if (defined(__i386__) || defined(__i486__) || defined(__i586__) || defined(__i686__) || defined(_M_IX86) || defined(_X86_) || defined(__I86__)) // 32-bit Intel machines usually average about one every 100ms #define ZT_IDENTITY_VALIDATION_SOURCE_RATE_LIMIT 5000 #else // This provides a safe margin for ARM, MIPS, etc. that usually average one every 250-400ms #define ZT_IDENTITY_VALIDATION_SOURCE_RATE_LIMIT 10000 #endif #endif /** * How long is a path or peer considered to have a trust relationship with us (for e.g. relay policy) since last trusted established packet? */ #define ZT_TRUST_EXPIRATION 600000 /** * Desired buffer size for UDP sockets (used in service and osdep but defined here) */ #define ZT_UDP_DESIRED_BUF_SIZE 1048576 /** * Desired / recommended min stack size for threads (used on some platforms to reset thread stack size) */ #define ZT_THREAD_MIN_STACK_SIZE 1048576 // Exceptions thrown in core ZT code #define ZT_EXCEPTION_OUT_OF_BOUNDS 100 #define ZT_EXCEPTION_OUT_OF_MEMORY 101 #define ZT_EXCEPTION_PRIVATE_KEY_REQUIRED 102 #define ZT_EXCEPTION_INVALID_ARGUMENT 103 #define ZT_EXCEPTION_INVALID_SERIALIZED_DATA_INVALID_TYPE 200 #define ZT_EXCEPTION_INVALID_SERIALIZED_DATA_OVERFLOW 201 #define ZT_EXCEPTION_INVALID_SERIALIZED_DATA_INVALID_CRYPTOGRAPHIC_TOKEN 202 #define ZT_EXCEPTION_INVALID_SERIALIZED_DATA_BAD_ENCODING 203 #endif