/*!
* hostlist.js - address management for hsd
* Copyright (c) 2017-2018, Christopher Jeffrey (MIT License).
* https://github.com/handshake-org/hsd
*/
'use strict';
const assert = require('bsert');
const path = require('path');
const fs = require('bfile');
const IP = require('binet');
const bio = require('bufio');
const Logger = require('blgr');
const Hash256 = require('bcrypto/lib/hash256');
const List = require('blst');
const rng = require('bcrypto/lib/random');
const secp256k1 = require('bcrypto/lib/secp256k1');
const {lookup} = require('./lookup');
const util = require('../utils/util');
const Network = require('../protocol/network');
const NetAddress = require('./netaddress');
const common = require('./common');
const seeds = require('./seeds');
/**
* Stochastic address manager based on bitcoin addrman.
*
* Design goals:
* * Keep the address tables in-memory, and asynchronously dump the entire
* table to hosts.json.
* * Make sure no (localized) attacker can fill the entire table with his
* nodes/addresses.
*
* To that end:
* * Addresses are organized into buckets that can each store up
* to 64 entries (maxEntries).
* * Addresses to which our node has not successfully connected go into
* 1024 "fresh" buckets (maxFreshBuckets).
* * Based on the address range of the source of information
* 64 buckets are selected at random.
* * The actual bucket is chosen from one of these, based on the range in
* which the address itself is located.
* * The position in the bucket is chosen based on the full address.
* * One single address can occur in up to 8 different buckets to increase
* selection chances for addresses that are seen frequently. The chance
* for increasing this multiplicity decreases exponentially.
* * When adding a new address to an occupied position of a bucket, it
* will not replace the existing entry unless that address is also stored
* in another bucket or it doesn't meet one of several quality criteria
* (see isStale for exact criteria).
* * Addresses of nodes that are known to be accessible go into 256 "tried"
* buckets.
* * Each address range selects at random 8 of these buckets.
* * The actual bucket is chosen from one of these, based on the full
* address.
* * Bucket selection is based on cryptographic hashing,
* using a randomly-generated 256-bit key, which should not be observable
* by adversaries (key).
*/
/**
* Host List
* @alias module:net.HostList
*/
class HostList {
/**
* Create a host list.
* @constructor
* @param {Object} options
*/
constructor(options) {
this.options = new HostListOptions(options);
this.network = this.options.network;
this.logger = this.options.logger.context('hostlist');
this.address = this.options.address;
this.brontide = this.options.brontide;
this.resolve = this.options.resolve;
this.random = this.options.random;
this.key = rng.randomBytes(32);
this.hash = new Hash256();
this.hashbuf = Buffer.alloc(4);
this.portbuf = Buffer.alloc(2);
this.dnsSeeds = [];
this.dnsNodes = [];
this.map = new Map();
this.fresh = [];
this.totalFresh = 0;
this.used = [];
this.totalUsed = 0;
this.nodes = [];
this.local = new Map();
this.banned = new Map();
this.maxFreshBuckets = 1024;
this.maxUsedBuckets = 256;
this.maxEntries = 64;
this.timer = null;
this.needsFlush = false;
this.flushing = false;
this.added = false;
this.init();
}
/**
* Initialize list.
* @private
*/
init() {
for (let i = 0; i < this.maxFreshBuckets; i++)
this.fresh.push(new Map());
for (let i = 0; i < this.maxUsedBuckets; i++)
this.used.push(new List());
}
/**
* Initialize list.
* @private
*/
initAdd() {
if (this.added)
return;
const options = this.options;
const scores = HostList.scores;
this.setSeeds(options.seeds);
this.setNodes(options.nodes);
this.pushLocal(this.address, scores.MANUAL);
this.pushLocal(this.brontide, scores.MANUAL);
this.addLocal(options.host, options.port, scores.BIND);
const hosts = IP.getPublic();
const port = this.address.port;
for (const host of hosts)
this.addLocal(host, port, scores.IF);
this.added = true;
}
/**
* Open hostlist and read hosts file.
* @method
* @returns {Promise}
*/
async open() {
this.initAdd();
try {
await this.loadFile();
} catch (e) {
this.logger.warning('Hosts deserialization failed.');
this.logger.error(e);
}
if (this.size() === 0)
this.injectSeeds();
await this.discoverNodes();
this.start();
}
/**
* Close hostlist.
* @method
* @returns {Promise}
*/
async close() {
this.stop();
await this.flush();
this.reset();
}
/**
* Start flush interval.
*/
start() {
if (this.options.memory)
return;
if (!this.options.filename)
return;
assert(this.timer == null);
this.timer = setInterval(() => this.flush(), this.options.flushInterval);
}
/**
* Stop flush interval.
*/
stop() {
if (this.options.memory)
return;
if (!this.options.filename)
return;
assert(this.timer != null);
clearInterval(this.timer);
this.timer = null;
}
/**
* Read and initialize from hosts file.
*/
injectSeeds() {
const nodes = seeds.get(this.network.type);
for (const node of nodes) {
const addr = NetAddress.fromHostname(node, this.network);
if (this.map.has(addr.hostname))
continue;
if (!addr.isRoutable())
continue;
if (!this.options.onion && addr.isOnion())
continue;
if (this.options.brontideOnly && !addr.hasKey())
continue;
if (addr.port === 0)
continue;
this.add(addr);
}
}
/**
* Read and initialize from hosts file.
* @method
* @returns {Promise}
*/
async loadFile() {
const filename = this.options.filename;
if (fs.unsupported)
return;
if (this.options.memory)
return;
if (!filename)
return;
let data;
try {
data = await fs.readFile(filename, 'utf8');
} catch (e) {
if (e.code === 'ENOENT')
return;
throw e;
}
const json = JSON.parse(data);
this.fromJSON(json);
}
/**
* Flush addrs to hosts file.
* @method
* @returns {Promise}
*/
async flush() {
const filename = this.options.filename;
if (fs.unsupported)
return;
if (this.options.memory)
return;
if (!filename)
return;
if (!this.needsFlush)
return;
if (this.flushing)
return;
this.needsFlush = false;
this.logger.debug('Writing hosts to %s.', filename);
const json = this.toJSON();
const data = JSON.stringify(json);
this.flushing = true;
try {
await fs.writeFile(filename, data, 'utf8');
} catch (e) {
this.logger.warning('Writing hosts failed.');
this.logger.error(e);
}
this.flushing = false;
}
/**
* Get list size.
* @returns {Number}
*/
size() {
return this.totalFresh + this.totalUsed;
}
/**
* Test whether the host list is full.
* @returns {Boolean}
*/
isFull() {
return this.totalFresh >= this.maxFreshBuckets * this.maxEntries;
}
/**
* Reset host list.
*/
reset() {
this.map.clear();
for (const bucket of this.fresh)
bucket.clear();
for (const bucket of this.used)
bucket.reset();
this.totalFresh = 0;
this.totalUsed = 0;
this.nodes.length = 0;
}
/**
* Mark a peer as banned.
* @param {String} host
*/
ban(host) {
this.banned.set(host, util.now());
}
/**
* Unban host.
* @param {String} host
*/
unban(host) {
this.banned.delete(host);
}
/**
* Clear banned hosts.
*/
clearBanned() {
this.banned.clear();
}
/**
* Test whether the host is banned.
* @param {String} host
* @returns {Boolean}
*/
isBanned(host) {
const time = this.banned.get(host);
if (time == null)
return false;
if (util.now() > time + this.options.banTime) {
this.banned.delete(host);
return false;
}
return true;
}
/**
* Allocate a new host.
* @returns {HostEntry}
*/
getHost() {
let buckets = null;
if (this.totalFresh > 0)
buckets = this.fresh;
if (this.totalUsed > 0) {
if (this.totalFresh === 0 || this.random(2) === 0)
buckets = this.used;
}
if (!buckets)
return null;
const now = this.network.now();
let factor = 1;
for (;;) {
const i = this.random(buckets.length);
const bucket = buckets[i];
if (bucket.size === 0)
continue;
let index = this.random(bucket.size);
let entry;
if (buckets === this.used) {
entry = bucket.head;
while (index--)
entry = entry.next;
} else {
for (entry of bucket.values()) {
if (index === 0)
break;
index -= 1;
}
}
const num = this.random(1 << 30);
if (num < factor * entry.chance(now) * (1 << 30))
return entry;
factor *= 1.2;
}
}
/**
* Get fresh bucket for host.
* @private
* @param {HostEntry} entry
* @param {NetAddress?} [src]
* @returns {Map}
*/
freshBucket(entry, src) {
const addr = entry.addr;
if (!src)
src = entry.src;
this.hash.init();
this.hash.update(this.key);
this.hash.update(addr.getGroup());
this.hash.update(src.getGroup());
const hash1 = this.hash.final();
const hash32 = bio.readU32(hash1, 0) % 64;
bio.writeU32(this.hashbuf, hash32, 0);
this.hash.init();
this.hash.update(this.key);
this.hash.update(src.getGroup());
this.hash.update(this.hashbuf);
const hash2 = this.hash.final();
const hash = bio.readU32(hash2, 0);
const index = hash % this.fresh.length;
return this.fresh[index];
}
/**
* Get used bucket for host.
* @private
* @param {HostEntry} entry
* @returns {List}
*/
usedBucket(entry) {
const addr = entry.addr;
bio.writeU16(this.portbuf, addr.port, 0);
this.hash.init();
this.hash.update(this.key);
this.hash.update(addr.raw);
this.hash.update(this.portbuf);
this.hash.update(addr.key);
const hash1 = this.hash.final();
const hash32 = bio.readU32(hash1, 0) % 8;
bio.writeU32(this.hashbuf, hash32, 0);
this.hash.init();
this.hash.update(this.key);
this.hash.update(addr.getGroup());
this.hash.update(this.hashbuf);
const hash2 = this.hash.final();
const hash = bio.readU32(hash2, 0);
const index = hash % this.used.length;
return this.used[index];
}
/**
* Add host to host list.
* @param {NetAddress} addr
* @param {NetAddress?} [src]
* @returns {Boolean}
*/
add(addr, src) {
assert(addr.port !== 0);
let entry = this.map.get(addr.hostname);
if (entry) {
let penalty = 2 * 60 * 60;
let interval = 24 * 60 * 60;
// No source means we're inserting
// this ourselves. No penalty.
if (!src)
penalty = 0;
// Update services.
entry.addr.services |= addr.services;
entry.addr.services >>>= 0;
// Online?
const now = this.network.now();
if (now - addr.time < 24 * 60 * 60)
interval = 60 * 60;
// Periodically update time.
if (entry.addr.time < addr.time - interval - penalty) {
entry.addr.time = addr.time;
this.needsFlush = true;
}
// Do not update if no new
// information is present.
if (entry.addr.time && addr.time <= entry.addr.time)
return false;
// Do not update if the entry was
// already in the "used" table.
if (entry.used)
return false;
assert(entry.refCount > 0);
// Do not update if the max
// reference count is reached.
if (entry.refCount === HostList.MAX_REFS)
return false;
assert(entry.refCount < HostList.MAX_REFS);
// Stochastic test: previous refCount
// N: 2^N times harder to increase it.
let factor = 1;
for (let i = 0; i < entry.refCount; i++)
factor *= 2;
if (this.random(factor) !== 0)
return false;
} else {
if (!src)
src = this.address;
entry = new HostEntry(addr, src);
this.totalFresh += 1;
}
const bucket = this.freshBucket(entry, src);
if (bucket.has(entry.key()))
return false;
if (bucket.size >= this.maxEntries)
this.evictFresh(bucket);
bucket.set(entry.key(), entry);
entry.refCount += 1;
this.map.set(entry.key(), entry);
this.needsFlush = true;
return true;
}
/**
* Evict a host from fresh bucket.
* @param {Map} bucket
*/
evictFresh(bucket) {
let old = null;
for (const entry of bucket.values()) {
if (this.isStale(entry)) {
bucket.delete(entry.key());
if (--entry.refCount === 0) {
this.map.delete(entry.key());
this.totalFresh -= 1;
}
continue;
}
if (!old) {
old = entry;
continue;
}
if (entry.addr.time < old.addr.time)
old = entry;
}
if (!old)
return;
bucket.delete(old.key());
if (--old.refCount === 0) {
this.map.delete(old.key());
this.totalFresh -= 1;
}
}
/**
* Test whether a host is evictable.
* @param {HostEntry} entry
* @returns {Boolean}
*/
isStale(entry) {
const now = this.network.now();
if (entry.lastAttempt && entry.lastAttempt >= now - 60)
return false;
if (entry.addr.time > now + 10 * 60)
return true;
if (entry.addr.time === 0)
return true;
if (now - entry.addr.time > HostList.HORIZON_DAYS * 24 * 60 * 60)
return true;
if (entry.lastSuccess === 0 && entry.attempts >= HostList.RETRIES)
return true;
if (now - entry.lastSuccess > HostList.MIN_FAIL_DAYS * 24 * 60 * 60) {
if (entry.attempts >= HostList.MAX_FAILURES)
return true;
}
return false;
}
/**
* Remove host from host list.
* @param {String} hostname
* @returns {NetAddress}
*/
remove(hostname) {
const entry = this.map.get(hostname);
if (!entry)
return null;
if (entry.used) {
let head = entry;
assert(entry.refCount === 0);
while (head.prev)
head = head.prev;
for (const bucket of this.used) {
if (bucket.head === head) {
bucket.remove(entry);
this.totalUsed -= 1;
head = null;
break;
}
}
assert(!head);
} else {
for (const bucket of this.fresh) {
if (bucket.delete(entry.key()))
entry.refCount -= 1;
}
this.totalFresh -= 1;
assert(entry.refCount === 0);
}
this.map.delete(entry.key());
return entry.addr;
}
/**
* Mark host as failed.
* @param {String} hostname
*/
markAttempt(hostname) {
const entry = this.map.get(hostname);
const now = this.network.now();
if (!entry)
return;
entry.attempts += 1;
entry.lastAttempt = now;
}
/**
* Mark host as successfully connected.
* @param {String} hostname
*/
markSuccess(hostname) {
const entry = this.map.get(hostname);
const now = this.network.now();
if (!entry)
return;
if (now - entry.addr.time > 20 * 60)
entry.addr.time = now;
}
/**
* Mark host as successfully ack'd.
* @param {String} hostname
* @param {Number} services
*/
markAck(hostname, services) {
const entry = this.map.get(hostname);
if (!entry)
return;
const now = this.network.now();
entry.addr.services |= services;
entry.addr.services >>>= 0;
entry.lastSuccess = now;
entry.lastAttempt = now;
entry.attempts = 0;
if (entry.used)
return;
assert(entry.refCount > 0);
// Remove from fresh.
let old = null;
for (const bucket of this.fresh) {
if (bucket.delete(entry.key())) {
entry.refCount -= 1;
old = bucket;
}
}
assert(old);
assert(entry.refCount === 0);
this.totalFresh -= 1;
// Find room in used bucket.
const bucket = this.usedBucket(entry);
if (bucket.size < this.maxEntries) {
entry.used = true;
bucket.push(entry);
this.totalUsed += 1;
return;
}
// No room. Evict.
const evicted = this.evictUsed(bucket);
let fresh = this.freshBucket(evicted);
// Move to entry's old bucket if no room.
if (fresh.size >= this.maxEntries)
fresh = old;
// Swap to evicted's used bucket.
entry.used = true;
bucket.replace(evicted, entry);
// Move evicted to fresh bucket.
evicted.used = false;
fresh.set(evicted.key(), evicted);
assert(evicted.refCount === 0);
evicted.refCount += 1;
this.totalFresh += 1;
}
/**
* Pick used for eviction.
* @param {List} bucket
*/
evictUsed(bucket) {
let old = bucket.head;
for (let entry = bucket.head; entry; entry = entry.next) {
if (entry.addr.time < old.addr.time)
old = entry;
}
return old;
}
/**
* Convert address list to array.
* @returns {NetAddress[]}
*/
toArray() {
const items = [];
const out = [];
for (const entry of this.map.values())
items.push(entry);
for (let i = 0; i < items.length && out.length < 2500; i++) {
const j = this.random(items.length - i);
[items[i], items[i + j]] = [items[i + j], items[i]];
const entry = items[i];
if (!this.isStale(entry))
out.push(entry.addr);
}
return out;
}
/**
* Add a preferred seed.
* @param {String} host
*/
addSeed(host) {
const ip = IP.fromHostname(host);
if (ip.type === IP.types.NONE) {
// Defer for resolution.
this.dnsSeeds.push(ip);
return null;
}
if (ip.port === 0)
ip.port = ip.key ? this.network.brontidePort : this.network.port;
const addr = NetAddress.fromHost(ip.host, ip.port, ip.key, this.network);
this.add(addr);
return addr;
}
/**
* Add a priority node.
* @param {String} host
* @returns {NetAddress}
*/
addNode(host) {
const ip = IP.fromHostname(host);
if (ip.type === IP.types.NONE) {
// Defer for resolution.
this.dnsNodes.push(ip);
return null;
}
if (ip.port === 0)
ip.port = ip.key ? this.network.brontidePort : this.network.port;
const addr = NetAddress.fromHost(ip.host, ip.port, ip.key, this.network);
this.nodes.push(addr);
this.add(addr);
return addr;
}
/**
* Remove a priority node.
* @param {String} host
* @returns {Boolean}
*/
removeNode(host) {
const addr = IP.fromHostname(host);
if (addr.port === 0)
addr.port = addr.key ? this.network.brontidePort : this.network.port;
for (let i = 0; i < this.nodes.length; i++) {
const node = this.nodes[i];
if (node.host !== addr.host)
continue;
if (node.port !== addr.port)
continue;
this.nodes.splice(i, 1);
return true;
}
return false;
}
/**
* Set initial seeds.
* @param {String[]} seeds
*/
setSeeds(seeds) {
this.dnsSeeds.length = 0;
for (const host of seeds)
this.addSeed(host);
}
/**
* Set priority nodes.
* @param {String[]} nodes
*/
setNodes(nodes) {
this.dnsNodes.length = 0;
this.nodes.length = 0;
for (const host of nodes)
this.addNode(host);
}
/**
* Add a local address.
* @param {String} host
* @param {Number} port
* @param {Number} score
* @returns {Boolean}
*/
addLocal(host, port, score) {
const addr = NetAddress.fromHost(host, port, null, this.network);
addr.services = this.options.services;
return this.pushLocal(addr, score);
}
/**
* Add a local address.
* @param {NetAddress} addr
* @param {Number} score
* @returns {Boolean}
*/
pushLocal(addr, score) {
if (!addr.isRoutable())
return false;
if (this.local.has(addr.hostname))
return false;
const local = new LocalAddress(addr, score);
this.local.set(addr.hostname, local);
return true;
}
/**
* Get local address based on reachability.
* @param {NetAddress?} src
* @returns {NetAddress}
*/
getLocal(src) {
let bestReach = -1;
let bestScore = -1;
let bestDest = null;
if (!src) {
for (const dest of this.local.values()) {
// Disable everything except MANUAL
if (dest.type < HostList.scores.UPNP)
continue;
if (dest.addr.hasKey())
continue;
if (dest.score > bestScore) {
bestScore = dest.score;
bestDest = dest.addr;
}
}
return bestDest;
}
for (const dest of this.local.values()) {
// Disable everything except MANUAL
if (dest.type < HostList.scores.UPNP)
continue;
if (dest.addr.hasKey())
continue;
const reach = src.getReachability(dest.addr);
if (reach < bestReach)
continue;
if (reach > bestReach || dest.score > bestScore) {
bestReach = reach;
bestScore = dest.score;
bestDest = dest.addr;
}
}
if (bestDest)
bestDest.time = this.network.now();
return bestDest;
}
/**
* Mark local address as seen during a handshake.
* @param {NetAddress} addr
* @returns {Boolean}
*/
markLocal(addr) {
const local = this.local.get(addr.hostname);
if (!local)
return false;
local.score += 1;
return true;
}
/**
* Discover hosts from seeds.
* @method
* @returns {Promise}
*/
async discoverSeeds() {
const jobs = [];
for (const seed of this.dnsSeeds)
jobs.push(this.populateSeed(seed));
return Promise.all(jobs);
}
/**
* Discover hosts from nodes.
* @method
* @returns {Promise}
*/
async discoverNodes() {
const jobs = [];
for (const node of this.dnsNodes)
jobs.push(this.populateNode(node));
return Promise.all(jobs);
}
/**
* Lookup node's domain.
* @method
* @param {Object} addr
* @returns {Promise}
*/
async populateNode(addr) {
const addrs = await this.populate(addr);
if (addrs.length === 0)
return;
this.nodes.push(addrs[0]);
this.add(addrs[0]);
}
/**
* Populate from seed.
* @method
* @param {Object} seed
* @returns {Promise}
*/
async populateSeed(seed) {
const addrs = await this.populate(seed);
for (const addr of addrs)
this.add(addr);
}
/**
* Lookup hosts from dns host.
* @method
* @param {Object} target
* @returns {Promise}
*/
async populate(target) {
const addrs = [];
assert(target.type === IP.types.NONE, 'Resolved host passed.');
this.logger.info('Resolving host: %s.', target.host);
let hosts;
try {
hosts = await this.resolve(target.host);
} catch (e) {
this.logger.error(e);
return addrs;
}
for (const host of hosts) {
const addr =
NetAddress.fromHost(host, this.network.port, null, this.network);
addrs.push(addr);
}
return addrs;
}
/**
* Convert host list to json-friendly object.
* @returns {Object}
*/
toJSON() {
const addrs = [];
const fresh = [];
const used = [];
for (const entry of this.map.values())
addrs.push(entry.toJSON());
for (const bucket of this.fresh) {
const keys = [];
for (const key of bucket.keys())
keys.push(key);
fresh.push(keys);
}
for (const bucket of this.used) {
const keys = [];
for (let entry = bucket.head; entry; entry = entry.next)
keys.push(entry.key());
used.push(keys);
}
return {
version: HostList.VERSION,
network: this.network.type,
magic: this.network.magic,
key: this.key.toString('hex'),
addrs: addrs,
fresh: fresh,
used: used
};
}
/**
* Inject properties from json object.
* @private
* @param {Object} json
* @returns {HostList}
*/
fromJSON(json) {
const sources = new Map();
const map = new Map();
const fresh = [];
const used = [];
let totalFresh = 0;
let totalUsed = 0;
assert(json && typeof json === 'object');
assert(!json.network || json.network === this.network.type,
'Network mismatch.');
assert(json.magic === this.network.magic, 'Magic mismatch.');
if (json.version < 4) {
// Migrate to v4.
for (const item of json.addrs) {
const entry = HostEntry.fromJSON(item, this.network);
const {addr, src} = entry;
const time = addr.time;
if (!entry.lastSuccess)
continue;
this.add(addr, src);
this.markAttempt(addr.hostname);
this.markSuccess(addr.hostname);
this.markAck(addr.hostname, 0);
const e = this.map.get(addr.hostname);
if (e) {
e.attempts = entry.attempts;
e.lastSuccess = entry.lastSuccess;
e.lastAttempt = entry.lastAttempt;
e.addr.time = time;
}
}
this.injectSeeds();
return this;
}
assert(json.version === HostList.VERSION,
'Bad address serialization version.');
assert(typeof json.key === 'string');
assert(Array.isArray(json.addrs));
const key = Buffer.from(json.key, 'hex');
assert(key.length === 32);
for (const addr of json.addrs) {
const entry = HostEntry.fromJSON(addr, this.network);
let src = sources.get(entry.src.hostname);
// Save some memory.
if (!src) {
src = entry.src;
sources.set(src.hostname, src);
}
entry.src = src;
map.set(entry.key(), entry);
}
assert(Array.isArray(json.fresh));
assert(json.fresh.length <= this.maxFreshBuckets,
'Buckets mismatch.');
for (const keys of json.fresh) {
const bucket = new Map();
for (const key of keys) {
const entry = map.get(key);
assert(entry);
if (entry.refCount === 0)
totalFresh += 1;
entry.refCount += 1;
bucket.set(key, entry);
}
assert(bucket.size <= this.maxEntries,
'Bucket size mismatch.');
fresh.push(bucket);
}
assert(fresh.length === this.fresh.length,
'Buckets mismatch.');
assert(Array.isArray(json.used));
assert(json.used.length <= this.maxUsedBuckets,
'Buckets mismatch.');
for (const keys of json.used) {
const bucket = new List();
for (const key of keys) {
const entry = map.get(key);
assert(entry);
assert(entry.refCount === 0);
assert(!entry.used);
entry.used = true;
totalUsed += 1;
bucket.push(entry);
}
assert(bucket.size <= this.maxEntries,
'Bucket size mismatch.');
used.push(bucket);
}
assert(used.length === this.used.length,
'Buckets mismatch.');
for (const entry of map.values())
assert(entry.used || entry.refCount > 0);
this.key = key;
this.map = map;
this.fresh = fresh;
this.totalFresh = totalFresh;
this.used = used;
this.totalUsed = totalUsed;
return this;
}
/**
* Instantiate host list from json object.
* @param {Object} options
* @param {Object} json
* @returns {HostList}
*/
static fromJSON(options, json) {
return new this(options).fromJSON(json);
}
}
/**
* Number of days before considering
* an address stale.
* @const {Number}
* @default
*/
HostList.HORIZON_DAYS = 30;
/**
* Number of retries (without success)
* before considering an address stale.
* @const {Number}
* @default
*/
HostList.RETRIES = 3;
/**
* Number of days after reaching
* MAX_FAILURES to consider an
* address stale.
* @const {Number}
* @default
*/
HostList.MIN_FAIL_DAYS = 7;
/**
* Maximum number of failures
* allowed before considering
* an address stale.
* @const {Number}
* @default
*/
HostList.MAX_FAILURES = 10;
/**
* Maximum number of references
* in fresh buckets.
* @const {Number}
* @default
*/
HostList.MAX_REFS = 8;
/**
* Serialization version.
* @const {Number}
* @default
*/
HostList.VERSION = 4;
/**
* Local address scores.
* @enum {Number}
* @default
*/
HostList.scores = {
NONE: 0,
IF: 1,
BIND: 2,
DNS: 3,
UPNP: 4,
MANUAL: 5,
MAX: 6
};
/**
* Host Entry
* @alias module:net.HostEntry
* @property {NetAddress} addr - host address.
* @property {NetAddress} src - the first address we discovered this entry
* from.
* @property {Boolean} used - is it in the used set.
* @property {Number} refCount - Reference count in new buckets.
* @property {Number} attempts - connection attempts since last successful one.
* @property {Number} lastSuccess - last success timestamp.
* @property {Number} lastAttempt - last attempt timestamp.
*/
class HostEntry {
/**
* Create a host entry.
* @constructor
* @param {NetAddress} [addr]
* @param {NetAddress} [src]
*/
constructor(addr, src) {
this.addr = addr || new NetAddress();
this.src = src || new NetAddress();
this.prev = null;
this.next = null;
this.used = false;
this.refCount = 0;
this.attempts = 0;
this.lastSuccess = 0;
this.lastAttempt = 0;
if (addr)
this.fromOptions(addr, src);
}
/**
* Inject properties from options.
* @private
* @param {NetAddress} addr
* @param {NetAddress} src
* @returns {HostEntry}
*/
fromOptions(addr, src) {
assert(addr instanceof NetAddress);
assert(src instanceof NetAddress);
this.addr = addr;
this.src = src;
return this;
}
/**
* Instantiate host entry from options.
* @param {NetAddress} addr
* @param {NetAddress} src
* @returns {HostEntry}
*/
static fromOptions(addr, src) {
return new this().fromOptions(addr, src);
}
/**
* Get key suitable for a hash table (hostname).
* @returns {String}
*/
key() {
return this.addr.hostname;
}
/**
* Get host priority.
* @param {Number} now
* @returns {Number}
*/
chance(now) {
let c = 1;
if (now - this.lastAttempt < 60 * 10)
c *= 0.01;
c *= Math.pow(0.66, Math.min(this.attempts, 8));
return c;
}
/**
* Inspect host address.
* @returns {Object}
*/
inspect() {
return {
addr: this.addr,
src: this.src,
used: this.used,
refCount: this.refCount,
attempts: this.attempts,
lastSuccess: util.date(this.lastSuccess),
lastAttempt: util.date(this.lastAttempt)
};
}
/**
* Convert host entry to json-friendly object.
* @returns {Object}
*/
toJSON() {
return {
addr: this.addr.hostname,
src: this.src.hostname,
services: this.addr.services.toString(2),
time: this.addr.time,
attempts: this.attempts,
lastSuccess: this.lastSuccess,
lastAttempt: this.lastAttempt
};
}
/**
* Inject properties from json object.
* @private
* @param {Object} json
* @param {Network} network
* @returns {HostEntry}
*/
fromJSON(json, network) {
assert(json && typeof json === 'object');
assert(typeof json.addr === 'string');
assert(typeof json.src === 'string');
this.addr.fromHostname(json.addr, network);
if (json.services != null) {
assert(typeof json.services === 'string');
assert(json.services.length > 0);
assert(json.services.length <= 32);
const services = parseInt(json.services, 2);
assert((services >>> 0) === services);
this.addr.services = services;
}
if (json.time != null) {
assert(Number.isSafeInteger(json.time));
assert(json.time >= 0);
this.addr.time = json.time;
}
if (json.src != null) {
assert(typeof json.src === 'string');
this.src.fromHostname(json.src, network);
}
if (json.attempts != null) {
assert((json.attempts >>> 0) === json.attempts);
this.attempts = json.attempts;
}
if (json.lastSuccess != null) {
assert(Number.isSafeInteger(json.lastSuccess));
assert(json.lastSuccess >= 0);
this.lastSuccess = json.lastSuccess;
}
if (json.lastAttempt != null) {
assert(Number.isSafeInteger(json.lastAttempt));
assert(json.lastAttempt >= 0);
this.lastAttempt = json.lastAttempt;
}
return this;
}
/**
* Instantiate host entry from json object.
* @param {Object} json
* @param {Network} network
* @returns {HostEntry}
*/
static fromJSON(json, network) {
return new this().fromJSON(json, network);
}
}
/**
* Local Address
* @alias module:net.LocalAddress
*/
class LocalAddress {
/**
* Create a local address.
* @constructor
* @param {NetAddress} addr
* @param {Number?} score
*/
constructor(addr, score) {
this.addr = addr;
this.type = score || 0;
this.score = score || 0;
}
}
/**
* Host List Options
* @alias module:net.HostListOptions
*/
class HostListOptions {
/**
* Create host list options.
* @constructor
* @param {Object?} options
*/
constructor(options) {
this.network = Network.primary;
this.logger = Logger.global;
this.resolve = lookup;
this.host = '0.0.0.0';
this.port = this.network.port;
this.services = common.LOCAL_SERVICES;
this.onion = false;
this.brontideOnly = false;
this.banTime = common.BAN_TIME;
this.random = random;
this.address = new NetAddress();
this.address.services = this.services;
this.address.time = this.network.now();
this.brontide = new NetAddress();
this.brontide.services = this.services;
this.brontide.time = this.network.now();
this.seeds = this.network.seeds;
this.nodes = [];
this.prefix = null;
this.filename = null;
this.memory = true;
this.flushInterval = 120000;
if (options)
this.fromOptions(options);
}
/**
* Inject properties from options.
* @private
* @param {Object} options
*/
fromOptions(options) {
assert(options, 'Options are required.');
if (options.network != null) {
this.network = Network.get(options.network);
this.seeds = this.network.seeds;
this.address.port = this.network.port;
this.brontide.port = this.network.brontidePort;
this.port = this.network.port;
}
if (options.logger != null) {
assert(typeof options.logger === 'object');
this.logger = options.logger;
}
if (options.resolve != null) {
assert(typeof options.resolve === 'function');
this.resolve = options.resolve;
}
if (options.banTime != null) {
assert(options.banTime >= 0);
this.banTime = options.banTime;
}
if (options.seeds) {
assert(Array.isArray(options.seeds));
this.seeds = options.seeds;
}
if (options.nodes) {
assert(Array.isArray(options.nodes));
this.nodes = options.nodes;
}
if (options.host != null)
this.host = IP.normalize(options.host);
if (options.port != null) {
assert((options.port & 0xffff) === options.port);
this.port = options.port;
}
if (options.publicHost != null) {
assert(typeof options.publicHost === 'string');
this.address.setHost(options.publicHost);
this.brontide.setHost(options.publicHost);
}
if (options.publicPort != null) {
assert((options.publicPort & 0xffff) === options.publicPort);
this.address.setPort(options.publicPort);
}
if (options.publicBrontidePort != null) {
assert((options.publicBrontidePort & 0xffff)
=== options.publicBrontidePort);
this.brontide.setPort(options.publicBrontidePort);
}
if (options.identityKey) {
assert(Buffer.isBuffer(options.identityKey),
'Identity key must be a buffer.');
assert(secp256k1.privateKeyVerify(options.identityKey),
'Invalid identity key.');
this.brontide.setKey(secp256k1.publicKeyCreate(options.identityKey));
}
if (options.services != null) {
assert(typeof options.services === 'number');
this.services = options.services;
}
if (options.onion != null) {
assert(typeof options.onion === 'boolean');
this.onion = options.onion;
}
if (options.brontideOnly != null) {
assert(typeof options.brontideOnly === 'boolean');
this.brontideOnly = options.brontideOnly;
}
if (options.memory != null) {
assert(typeof options.memory === 'boolean');
this.memory = options.memory;
}
if (options.prefix != null) {
assert(typeof options.prefix === 'string');
this.prefix = options.prefix;
this.filename = path.join(this.prefix, 'hosts.json');
}
if (options.filename != null) {
assert(typeof options.filename === 'string');
this.filename = options.filename;
}
if (options.flushInterval != null) {
assert(options.flushInterval >= 0);
this.flushInterval = options.flushInterval;
}
if (options.random != null) {
assert(typeof options.random === 'function');
this.random = options.random;;
}
this.address.time = this.network.now();
this.address.services = this.services;
this.brontide.time = this.network.now();
this.brontide.services = this.services;
return this;
}
}
/*
* Helpers
*/
function random(max) {
// Fast insecure randomness (a la bitcoin).
return Math.floor(Math.random() * max);
}
/*
* Expose
*/
HostList.HostEntry = HostEntry;
module.exports = HostList;