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|
// Copyright (c) 2012 Pieter Wuille
// Copyright (c) 2012-2020 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#ifndef BITCOIN_ADDRMAN_H
#define BITCOIN_ADDRMAN_H
#include <clientversion.h>
#include <config/bitcoin-config.h>
#include <fs.h>
#include <hash.h>
#include <netaddress.h>
#include <protocol.h>
#include <random.h>
#include <streams.h>
#include <sync.h>
#include <timedata.h>
#include <tinyformat.h>
#include <util/system.h>
#include <iostream>
#include <optional>
#include <set>
#include <stdint.h>
#include <unordered_map>
#include <vector>
/** Default for -checkaddrman */
static constexpr int32_t DEFAULT_ADDRMAN_CONSISTENCY_CHECKS{0};
/**
* Extended statistics about a CAddress
*/
class CAddrInfo : public CAddress
{
public:
//! last try whatsoever by us (memory only)
int64_t nLastTry{0};
//! last counted attempt (memory only)
int64_t nLastCountAttempt{0};
private:
//! where knowledge about this address first came from
CNetAddr source;
//! last successful connection by us
int64_t nLastSuccess{0};
//! connection attempts since last successful attempt
int nAttempts{0};
//! reference count in new sets (memory only)
int nRefCount{0};
//! in tried set? (memory only)
bool fInTried{false};
//! position in vRandom
mutable int nRandomPos{-1};
friend class CAddrMan;
friend class CAddrManDeterministic;
public:
SERIALIZE_METHODS(CAddrInfo, obj)
{
READWRITEAS(CAddress, obj);
READWRITE(obj.source, obj.nLastSuccess, obj.nAttempts);
}
CAddrInfo(const CAddress &addrIn, const CNetAddr &addrSource) : CAddress(addrIn), source(addrSource)
{
}
CAddrInfo() : CAddress(), source()
{
}
//! Calculate in which "tried" bucket this entry belongs
int GetTriedBucket(const uint256 &nKey, const std::vector<bool> &asmap) const;
//! Calculate in which "new" bucket this entry belongs, given a certain source
int GetNewBucket(const uint256 &nKey, const CNetAddr& src, const std::vector<bool> &asmap) const;
//! Calculate in which "new" bucket this entry belongs, using its default source
int GetNewBucket(const uint256 &nKey, const std::vector<bool> &asmap) const
{
return GetNewBucket(nKey, source, asmap);
}
//! Calculate in which position of a bucket to store this entry.
int GetBucketPosition(const uint256 &nKey, bool fNew, int nBucket) const;
//! Determine whether the statistics about this entry are bad enough so that it can just be deleted
bool IsTerrible(int64_t nNow = GetAdjustedTime()) const;
//! Calculate the relative chance this entry should be given when selecting nodes to connect to
double GetChance(int64_t nNow = GetAdjustedTime()) const;
};
/** Stochastic address manager
*
* Design goals:
* * Keep the address tables in-memory, and asynchronously dump the entire table to peers.dat.
* * 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.
* * Addresses to which our node has not successfully connected go into 1024 "new" buckets.
* * Based on the address range (/16 for IPv4) of the source of information, or if an asmap is provided,
* the AS it belongs to (for IPv4/IPv6), 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 IsTerrible 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.
* * When adding a new good address to an occupied position of a bucket, a FEELER connection to the
* old address is attempted. The old entry is only replaced and moved back to the "new" buckets if this
* attempt was unsuccessful.
* * Bucket selection is based on cryptographic hashing, using a randomly-generated 256-bit key, which should not
* be observable by adversaries.
* * Several indexes are kept for high performance. Setting m_consistency_check_ratio with the -checkaddrman
* configuration option will introduce (expensive) consistency checks for the entire data structure.
*/
//! total number of buckets for tried addresses
#define ADDRMAN_TRIED_BUCKET_COUNT_LOG2 8
//! total number of buckets for new addresses
#define ADDRMAN_NEW_BUCKET_COUNT_LOG2 10
//! maximum allowed number of entries in buckets for new and tried addresses
#define ADDRMAN_BUCKET_SIZE_LOG2 6
//! over how many buckets entries with tried addresses from a single group (/16 for IPv4) are spread
#define ADDRMAN_TRIED_BUCKETS_PER_GROUP 8
//! over how many buckets entries with new addresses originating from a single group are spread
#define ADDRMAN_NEW_BUCKETS_PER_SOURCE_GROUP 64
//! in how many buckets for entries with new addresses a single address may occur
#define ADDRMAN_NEW_BUCKETS_PER_ADDRESS 8
//! how old addresses can maximally be
#define ADDRMAN_HORIZON_DAYS 30
//! after how many failed attempts we give up on a new node
#define ADDRMAN_RETRIES 3
//! how many successive failures are allowed ...
#define ADDRMAN_MAX_FAILURES 10
//! ... in at least this many days
#define ADDRMAN_MIN_FAIL_DAYS 7
//! how recent a successful connection should be before we allow an address to be evicted from tried
#define ADDRMAN_REPLACEMENT_HOURS 4
//! Convenience
#define ADDRMAN_TRIED_BUCKET_COUNT (1 << ADDRMAN_TRIED_BUCKET_COUNT_LOG2)
#define ADDRMAN_NEW_BUCKET_COUNT (1 << ADDRMAN_NEW_BUCKET_COUNT_LOG2)
#define ADDRMAN_BUCKET_SIZE (1 << ADDRMAN_BUCKET_SIZE_LOG2)
//! the maximum number of tried addr collisions to store
#define ADDRMAN_SET_TRIED_COLLISION_SIZE 10
//! the maximum time we'll spend trying to resolve a tried table collision, in seconds
static const int64_t ADDRMAN_TEST_WINDOW = 40*60; // 40 minutes
/**
* Stochastical (IP) address manager
*/
class CAddrMan
{
public:
// Compressed IP->ASN mapping, loaded from a file when a node starts.
// Should be always empty if no file was provided.
// This mapping is then used for bucketing nodes in Addrman.
//
// If asmap is provided, nodes will be bucketed by
// AS they belong to, in order to make impossible for a node
// to connect to several nodes hosted in a single AS.
// This is done in response to Erebus attack, but also to generally
// diversify the connections every node creates,
// especially useful when a large fraction of nodes
// operate under a couple of cloud providers.
//
// If a new asmap was provided, the existing records
// would be re-bucketed accordingly.
std::vector<bool> m_asmap;
// Read asmap from provided binary file
static std::vector<bool> DecodeAsmap(fs::path path);
/**
* Serialized format.
* * format version byte (@see `Format`)
* * lowest compatible format version byte. This is used to help old software decide
* whether to parse the file. For example:
* * Bitcoin Core version N knows how to parse up to format=3. If a new format=4 is
* introduced in version N+1 that is compatible with format=3 and it is known that
* version N will be able to parse it, then version N+1 will write
* (format=4, lowest_compatible=3) in the first two bytes of the file, and so
* version N will still try to parse it.
* * Bitcoin Core version N+2 introduces a new incompatible format=5. It will write
* (format=5, lowest_compatible=5) and so any versions that do not know how to parse
* format=5 will not try to read the file.
* * nKey
* * nNew
* * nTried
* * number of "new" buckets XOR 2**30
* * all new addresses (total count: nNew)
* * all tried addresses (total count: nTried)
* * for each new bucket:
* * number of elements
* * for each element: index in the serialized "all new addresses"
* * asmap checksum
*
* 2**30 is xorred with the number of buckets to make addrman deserializer v0 detect it
* as incompatible. This is necessary because it did not check the version number on
* deserialization.
*
* vvNew, vvTried, mapInfo, mapAddr and vRandom are never encoded explicitly;
* they are instead reconstructed from the other information.
*
* This format is more complex, but significantly smaller (at most 1.5 MiB), and supports
* changes to the ADDRMAN_ parameters without breaking the on-disk structure.
*
* We don't use SERIALIZE_METHODS since the serialization and deserialization code has
* very little in common.
*/
template <typename Stream>
void Serialize(Stream& s_) const
EXCLUSIVE_LOCKS_REQUIRED(!cs)
{
LOCK(cs);
// Always serialize in the latest version (FILE_FORMAT).
OverrideStream<Stream> s(&s_, s_.GetType(), s_.GetVersion() | ADDRV2_FORMAT);
s << static_cast<uint8_t>(FILE_FORMAT);
// Increment `lowest_compatible` iff a newly introduced format is incompatible with
// the previous one.
static constexpr uint8_t lowest_compatible = Format::V3_BIP155;
s << static_cast<uint8_t>(INCOMPATIBILITY_BASE + lowest_compatible);
s << nKey;
s << nNew;
s << nTried;
int nUBuckets = ADDRMAN_NEW_BUCKET_COUNT ^ (1 << 30);
s << nUBuckets;
std::unordered_map<int, int> mapUnkIds;
int nIds = 0;
for (const auto& entry : mapInfo) {
mapUnkIds[entry.first] = nIds;
const CAddrInfo &info = entry.second;
if (info.nRefCount) {
assert(nIds != nNew); // this means nNew was wrong, oh ow
s << info;
nIds++;
}
}
nIds = 0;
for (const auto& entry : mapInfo) {
const CAddrInfo &info = entry.second;
if (info.fInTried) {
assert(nIds != nTried); // this means nTried was wrong, oh ow
s << info;
nIds++;
}
}
for (int bucket = 0; bucket < ADDRMAN_NEW_BUCKET_COUNT; bucket++) {
int nSize = 0;
for (int i = 0; i < ADDRMAN_BUCKET_SIZE; i++) {
if (vvNew[bucket][i] != -1)
nSize++;
}
s << nSize;
for (int i = 0; i < ADDRMAN_BUCKET_SIZE; i++) {
if (vvNew[bucket][i] != -1) {
int nIndex = mapUnkIds[vvNew[bucket][i]];
s << nIndex;
}
}
}
// Store asmap checksum after bucket entries so that it
// can be ignored by older clients for backward compatibility.
uint256 asmap_checksum;
if (m_asmap.size() != 0) {
asmap_checksum = SerializeHash(m_asmap);
}
s << asmap_checksum;
}
template <typename Stream>
void Unserialize(Stream& s_)
EXCLUSIVE_LOCKS_REQUIRED(!cs)
{
LOCK(cs);
assert(vRandom.empty());
Format format;
s_ >> Using<CustomUintFormatter<1>>(format);
int stream_version = s_.GetVersion();
if (format >= Format::V3_BIP155) {
// Add ADDRV2_FORMAT to the version so that the CNetAddr and CAddress
// unserialize methods know that an address in addrv2 format is coming.
stream_version |= ADDRV2_FORMAT;
}
OverrideStream<Stream> s(&s_, s_.GetType(), stream_version);
uint8_t compat;
s >> compat;
const uint8_t lowest_compatible = compat - INCOMPATIBILITY_BASE;
if (lowest_compatible > FILE_FORMAT) {
throw std::ios_base::failure(strprintf(
"Unsupported format of addrman database: %u. It is compatible with formats >=%u, "
"but the maximum supported by this version of %s is %u.",
format, lowest_compatible, PACKAGE_NAME, static_cast<uint8_t>(FILE_FORMAT)));
}
s >> nKey;
s >> nNew;
s >> nTried;
int nUBuckets = 0;
s >> nUBuckets;
if (format >= Format::V1_DETERMINISTIC) {
nUBuckets ^= (1 << 30);
}
if (nNew > ADDRMAN_NEW_BUCKET_COUNT * ADDRMAN_BUCKET_SIZE || nNew < 0) {
throw std::ios_base::failure(
strprintf("Corrupt CAddrMan serialization: nNew=%d, should be in [0, %u]",
nNew,
ADDRMAN_NEW_BUCKET_COUNT * ADDRMAN_BUCKET_SIZE));
}
if (nTried > ADDRMAN_TRIED_BUCKET_COUNT * ADDRMAN_BUCKET_SIZE || nTried < 0) {
throw std::ios_base::failure(
strprintf("Corrupt CAddrMan serialization: nTried=%d, should be in [0, %u]",
nTried,
ADDRMAN_TRIED_BUCKET_COUNT * ADDRMAN_BUCKET_SIZE));
}
// Deserialize entries from the new table.
for (int n = 0; n < nNew; n++) {
CAddrInfo &info = mapInfo[n];
s >> info;
mapAddr[info] = n;
info.nRandomPos = vRandom.size();
vRandom.push_back(n);
}
nIdCount = nNew;
// Deserialize entries from the tried table.
int nLost = 0;
for (int n = 0; n < nTried; n++) {
CAddrInfo info;
s >> info;
int nKBucket = info.GetTriedBucket(nKey, m_asmap);
int nKBucketPos = info.GetBucketPosition(nKey, false, nKBucket);
if (info.IsValid()
&& vvTried[nKBucket][nKBucketPos] == -1) {
info.nRandomPos = vRandom.size();
info.fInTried = true;
vRandom.push_back(nIdCount);
mapInfo[nIdCount] = info;
mapAddr[info] = nIdCount;
vvTried[nKBucket][nKBucketPos] = nIdCount;
nIdCount++;
} else {
nLost++;
}
}
nTried -= nLost;
// Store positions in the new table buckets to apply later (if possible).
// An entry may appear in up to ADDRMAN_NEW_BUCKETS_PER_ADDRESS buckets,
// so we store all bucket-entry_index pairs to iterate through later.
std::vector<std::pair<int, int>> bucket_entries;
for (int bucket = 0; bucket < nUBuckets; ++bucket) {
int num_entries{0};
s >> num_entries;
for (int n = 0; n < num_entries; ++n) {
int entry_index{0};
s >> entry_index;
if (entry_index >= 0 && entry_index < nNew) {
bucket_entries.emplace_back(bucket, entry_index);
}
}
}
// If the bucket count and asmap checksum haven't changed, then attempt
// to restore the entries to the buckets/positions they were in before
// serialization.
uint256 supplied_asmap_checksum;
if (m_asmap.size() != 0) {
supplied_asmap_checksum = SerializeHash(m_asmap);
}
uint256 serialized_asmap_checksum;
if (format >= Format::V2_ASMAP) {
s >> serialized_asmap_checksum;
}
const bool restore_bucketing{nUBuckets == ADDRMAN_NEW_BUCKET_COUNT &&
serialized_asmap_checksum == supplied_asmap_checksum};
if (!restore_bucketing) {
LogPrint(BCLog::ADDRMAN, "Bucketing method was updated, re-bucketing addrman entries from disk\n");
}
for (auto bucket_entry : bucket_entries) {
int bucket{bucket_entry.first};
const int entry_index{bucket_entry.second};
CAddrInfo& info = mapInfo[entry_index];
// Don't store the entry in the new bucket if it's not a valid address for our addrman
if (!info.IsValid()) continue;
// The entry shouldn't appear in more than
// ADDRMAN_NEW_BUCKETS_PER_ADDRESS. If it has already, just skip
// this bucket_entry.
if (info.nRefCount >= ADDRMAN_NEW_BUCKETS_PER_ADDRESS) continue;
int bucket_position = info.GetBucketPosition(nKey, true, bucket);
if (restore_bucketing && vvNew[bucket][bucket_position] == -1) {
// Bucketing has not changed, using existing bucket positions for the new table
vvNew[bucket][bucket_position] = entry_index;
++info.nRefCount;
} else {
// In case the new table data cannot be used (bucket count wrong or new asmap),
// try to give them a reference based on their primary source address.
bucket = info.GetNewBucket(nKey, m_asmap);
bucket_position = info.GetBucketPosition(nKey, true, bucket);
if (vvNew[bucket][bucket_position] == -1) {
vvNew[bucket][bucket_position] = entry_index;
++info.nRefCount;
}
}
}
// Prune new entries with refcount 0 (as a result of collisions or invalid address).
int nLostUnk = 0;
for (auto it = mapInfo.cbegin(); it != mapInfo.cend(); ) {
if (it->second.fInTried == false && it->second.nRefCount == 0) {
const auto itCopy = it++;
Delete(itCopy->first);
++nLostUnk;
} else {
++it;
}
}
if (nLost + nLostUnk > 0) {
LogPrint(BCLog::ADDRMAN, "addrman lost %i new and %i tried addresses due to collisions or invalid addresses\n", nLostUnk, nLost);
}
Check();
}
private:
void Clear()
EXCLUSIVE_LOCKS_REQUIRED(!cs)
{
LOCK(cs);
std::vector<int>().swap(vRandom);
nKey = insecure_rand.rand256();
for (size_t bucket = 0; bucket < ADDRMAN_NEW_BUCKET_COUNT; bucket++) {
for (size_t entry = 0; entry < ADDRMAN_BUCKET_SIZE; entry++) {
vvNew[bucket][entry] = -1;
}
}
for (size_t bucket = 0; bucket < ADDRMAN_TRIED_BUCKET_COUNT; bucket++) {
for (size_t entry = 0; entry < ADDRMAN_BUCKET_SIZE; entry++) {
vvTried[bucket][entry] = -1;
}
}
nIdCount = 0;
nTried = 0;
nNew = 0;
nLastGood = 1; //Initially at 1 so that "never" is strictly worse.
mapInfo.clear();
mapAddr.clear();
}
public:
explicit CAddrMan(bool deterministic, int32_t consistency_check_ratio)
: insecure_rand{deterministic},
m_consistency_check_ratio{consistency_check_ratio}
{
Clear();
if (deterministic) nKey = uint256{1};
}
~CAddrMan()
{
nKey.SetNull();
}
//! Return the number of (unique) addresses in all tables.
size_t size() const
EXCLUSIVE_LOCKS_REQUIRED(!cs)
{
LOCK(cs); // TODO: Cache this in an atomic to avoid this overhead
return vRandom.size();
}
//! Add addresses to addrman's new table.
bool Add(const std::vector<CAddress> &vAddr, const CNetAddr& source, int64_t nTimePenalty = 0)
EXCLUSIVE_LOCKS_REQUIRED(!cs)
{
LOCK(cs);
int nAdd = 0;
Check();
for (std::vector<CAddress>::const_iterator it = vAddr.begin(); it != vAddr.end(); it++)
nAdd += Add_(*it, source, nTimePenalty) ? 1 : 0;
Check();
if (nAdd) {
LogPrint(BCLog::ADDRMAN, "Added %i addresses from %s: %i tried, %i new\n", nAdd, source.ToString(), nTried, nNew);
}
return nAdd > 0;
}
//! Mark an entry as accessible.
void Good(const CService &addr, int64_t nTime = GetAdjustedTime())
EXCLUSIVE_LOCKS_REQUIRED(!cs)
{
LOCK(cs);
Check();
Good_(addr, /* test_before_evict */ true, nTime);
Check();
}
//! Mark an entry as connection attempted to.
void Attempt(const CService &addr, bool fCountFailure, int64_t nTime = GetAdjustedTime())
EXCLUSIVE_LOCKS_REQUIRED(!cs)
{
LOCK(cs);
Check();
Attempt_(addr, fCountFailure, nTime);
Check();
}
//! See if any to-be-evicted tried table entries have been tested and if so resolve the collisions.
void ResolveCollisions()
EXCLUSIVE_LOCKS_REQUIRED(!cs)
{
LOCK(cs);
Check();
ResolveCollisions_();
Check();
}
//! Randomly select an address in tried that another address is attempting to evict.
CAddrInfo SelectTriedCollision()
EXCLUSIVE_LOCKS_REQUIRED(!cs)
{
LOCK(cs);
Check();
const CAddrInfo ret = SelectTriedCollision_();
Check();
return ret;
}
/**
* Choose an address to connect to.
*/
CAddrInfo Select(bool newOnly = false) const
EXCLUSIVE_LOCKS_REQUIRED(!cs)
{
LOCK(cs);
Check();
const CAddrInfo addrRet = Select_(newOnly);
Check();
return addrRet;
}
/**
* Return all or many randomly selected addresses, optionally by network.
*
* @param[in] max_addresses Maximum number of addresses to return (0 = all).
* @param[in] max_pct Maximum percentage of addresses to return (0 = all).
* @param[in] network Select only addresses of this network (nullopt = all).
*/
std::vector<CAddress> GetAddr(size_t max_addresses, size_t max_pct, std::optional<Network> network) const
EXCLUSIVE_LOCKS_REQUIRED(!cs)
{
LOCK(cs);
Check();
std::vector<CAddress> vAddr;
GetAddr_(vAddr, max_addresses, max_pct, network);
Check();
return vAddr;
}
//! Outer function for Connected_()
void Connected(const CService &addr, int64_t nTime = GetAdjustedTime())
EXCLUSIVE_LOCKS_REQUIRED(!cs)
{
LOCK(cs);
Check();
Connected_(addr, nTime);
Check();
}
void SetServices(const CService &addr, ServiceFlags nServices)
EXCLUSIVE_LOCKS_REQUIRED(!cs)
{
LOCK(cs);
Check();
SetServices_(addr, nServices);
Check();
}
protected:
//! secret key to randomize bucket select with
uint256 nKey;
//! A mutex to protect the inner data structures.
mutable Mutex cs;
private:
//! Source of random numbers for randomization in inner loops
mutable FastRandomContext insecure_rand GUARDED_BY(cs);
//! Serialization versions.
enum Format : uint8_t {
V0_HISTORICAL = 0, //!< historic format, before commit e6b343d88
V1_DETERMINISTIC = 1, //!< for pre-asmap files
V2_ASMAP = 2, //!< for files including asmap version
V3_BIP155 = 3, //!< same as V2_ASMAP plus addresses are in BIP155 format
};
//! The maximum format this software knows it can unserialize. Also, we always serialize
//! in this format.
//! The format (first byte in the serialized stream) can be higher than this and
//! still this software may be able to unserialize the file - if the second byte
//! (see `lowest_compatible` in `Unserialize()`) is less or equal to this.
static constexpr Format FILE_FORMAT = Format::V3_BIP155;
//! The initial value of a field that is incremented every time an incompatible format
//! change is made (such that old software versions would not be able to parse and
//! understand the new file format). This is 32 because we overtook the "key size"
//! field which was 32 historically.
//! @note Don't increment this. Increment `lowest_compatible` in `Serialize()` instead.
static constexpr uint8_t INCOMPATIBILITY_BASE = 32;
//! last used nId
int nIdCount GUARDED_BY(cs);
//! table with information about all nIds
std::unordered_map<int, CAddrInfo> mapInfo GUARDED_BY(cs);
//! find an nId based on its network address
std::unordered_map<CNetAddr, int, CNetAddrHash> mapAddr GUARDED_BY(cs);
//! randomly-ordered vector of all nIds
//! This is mutable because it is unobservable outside the class, so any
//! changes to it (even in const methods) are also unobservable.
mutable std::vector<int> vRandom GUARDED_BY(cs);
// number of "tried" entries
int nTried GUARDED_BY(cs);
//! list of "tried" buckets
int vvTried[ADDRMAN_TRIED_BUCKET_COUNT][ADDRMAN_BUCKET_SIZE] GUARDED_BY(cs);
//! number of (unique) "new" entries
int nNew GUARDED_BY(cs);
//! list of "new" buckets
int vvNew[ADDRMAN_NEW_BUCKET_COUNT][ADDRMAN_BUCKET_SIZE] GUARDED_BY(cs);
//! last time Good was called (memory only)
int64_t nLastGood GUARDED_BY(cs);
//! Holds addrs inserted into tried table that collide with existing entries. Test-before-evict discipline used to resolve these collisions.
std::set<int> m_tried_collisions;
/** Perform consistency checks every m_consistency_check_ratio operations (if non-zero). */
const int32_t m_consistency_check_ratio;
//! Find an entry.
CAddrInfo* Find(const CNetAddr& addr, int *pnId = nullptr) EXCLUSIVE_LOCKS_REQUIRED(cs);
//! Create a new entry and add it to the internal data structures mapInfo, mapAddr and vRandom.
CAddrInfo* Create(const CAddress &addr, const CNetAddr &addrSource, int *pnId = nullptr) EXCLUSIVE_LOCKS_REQUIRED(cs);
//! Swap two elements in vRandom.
void SwapRandom(unsigned int nRandomPos1, unsigned int nRandomPos2) const EXCLUSIVE_LOCKS_REQUIRED(cs);
//! Move an entry from the "new" table(s) to the "tried" table
void MakeTried(CAddrInfo& info, int nId) EXCLUSIVE_LOCKS_REQUIRED(cs);
//! Delete an entry. It must not be in tried, and have refcount 0.
void Delete(int nId) EXCLUSIVE_LOCKS_REQUIRED(cs);
//! Clear a position in a "new" table. This is the only place where entries are actually deleted.
void ClearNew(int nUBucket, int nUBucketPos) EXCLUSIVE_LOCKS_REQUIRED(cs);
//! Mark an entry "good", possibly moving it from "new" to "tried".
void Good_(const CService &addr, bool test_before_evict, int64_t time) EXCLUSIVE_LOCKS_REQUIRED(cs);
//! Add an entry to the "new" table.
bool Add_(const CAddress &addr, const CNetAddr& source, int64_t nTimePenalty) EXCLUSIVE_LOCKS_REQUIRED(cs);
//! Mark an entry as attempted to connect.
void Attempt_(const CService &addr, bool fCountFailure, int64_t nTime) EXCLUSIVE_LOCKS_REQUIRED(cs);
//! Select an address to connect to, if newOnly is set to true, only the new table is selected from.
CAddrInfo Select_(bool newOnly) const EXCLUSIVE_LOCKS_REQUIRED(cs);
//! See if any to-be-evicted tried table entries have been tested and if so resolve the collisions.
void ResolveCollisions_() EXCLUSIVE_LOCKS_REQUIRED(cs);
//! Return a random to-be-evicted tried table address.
CAddrInfo SelectTriedCollision_() EXCLUSIVE_LOCKS_REQUIRED(cs);
//! Consistency check
void Check() const EXCLUSIVE_LOCKS_REQUIRED(cs)
{
AssertLockHeld(cs);
const int err = Check_();
if (err) {
LogPrintf("ADDRMAN CONSISTENCY CHECK FAILED!!! err=%i\n", err);
assert(false);
}
}
//! Perform consistency check. Returns an error code or zero.
int Check_() const EXCLUSIVE_LOCKS_REQUIRED(cs);
/**
* Return all or many randomly selected addresses, optionally by network.
*
* @param[out] vAddr Vector of randomly selected addresses from vRandom.
* @param[in] max_addresses Maximum number of addresses to return (0 = all).
* @param[in] max_pct Maximum percentage of addresses to return (0 = all).
* @param[in] network Select only addresses of this network (nullopt = all).
*/
void GetAddr_(std::vector<CAddress>& vAddr, size_t max_addresses, size_t max_pct, std::optional<Network> network) const EXCLUSIVE_LOCKS_REQUIRED(cs);
/** We have successfully connected to this peer. Calling this function
* updates the CAddress's nTime, which is used in our IsTerrible()
* decisions and gossiped to peers. Callers should be careful that updating
* this information doesn't leak topology information to network spies.
*
* net_processing calls this function when it *disconnects* from a peer to
* not leak information about currently connected peers.
*
* @param[in] addr The address of the peer we were connected to
* @param[in] nTime The time that we were last connected to this peer
*/
void Connected_(const CService& addr, int64_t nTime) EXCLUSIVE_LOCKS_REQUIRED(cs);
//! Update an entry's service bits.
void SetServices_(const CService &addr, ServiceFlags nServices) EXCLUSIVE_LOCKS_REQUIRED(cs);
friend class CAddrManTest;
friend class CAddrManDeterministic;
};
#endif // BITCOIN_ADDRMAN_H
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