// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2019 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#if defined(HAVE_CONFIG_H)
#include <config/bitcoin-config.h>
#endif
#include <net.h>
#include <banman.h>
#include <chainparams.h>
#include <clientversion.h>
#include <consensus/consensus.h>
#include <crypto/common.h>
#include <crypto/sha256.h>
#include <primitives/transaction.h>
#include <netbase.h>
#include <scheduler.h>
#include <ui_interface.h>
#include <util/strencodings.h>
#ifdef WIN32
#include <string.h>
#else
#include <fcntl.h>
#endif
#ifdef USE_POLL
#include <poll.h>
#endif
#ifdef USE_UPNP
#include <miniupnpc/miniupnpc.h>
#include <miniupnpc/miniwget.h>
#include <miniupnpc/upnpcommands.h>
#include <miniupnpc/upnperrors.h>
#endif
#include <unordered_map>
#include <math.h>
// Dump addresses to peers.dat every 15 minutes (900s)
static constexpr int DUMP_PEERS_INTERVAL = 15 * 60;
// We add a random period time (0 to 1 seconds) to feeler connections to prevent synchronization.
#define FEELER_SLEEP_WINDOW 1
// MSG_NOSIGNAL is not available on some platforms, if it doesn't exist define it as 0
#if !defined(MSG_NOSIGNAL)
#define MSG_NOSIGNAL 0
#endif
// MSG_DONTWAIT is not available on some platforms, if it doesn't exist define it as 0
#if !defined(MSG_DONTWAIT)
#define MSG_DONTWAIT 0
#endif
/** Used to pass flags to the Bind() function */
enum BindFlags {
BF_NONE = 0,
BF_EXPLICIT = (1U << 0),
BF_REPORT_ERROR = (1U << 1),
BF_WHITELIST = (1U << 2),
};
// The set of sockets cannot be modified while waiting
// The sleep time needs to be small to avoid new sockets stalling
static const uint64_t SELECT_TIMEOUT_MILLISECONDS = 50;
const std::string NET_MESSAGE_COMMAND_OTHER = "*other*";
static const uint64_t RANDOMIZER_ID_NETGROUP = 0x6c0edd8036ef4036ULL; // SHA256("netgroup")[0:8]
static const uint64_t RANDOMIZER_ID_LOCALHOSTNONCE = 0xd93e69e2bbfa5735ULL; // SHA256("localhostnonce")[0:8]
//
// Global state variables
//
bool fDiscover = true;
bool fListen = true;
bool g_relay_txes = !DEFAULT_BLOCKSONLY;
CCriticalSection cs_mapLocalHost;
std::map<CNetAddr, LocalServiceInfo> mapLocalHost GUARDED_BY(cs_mapLocalHost);
static bool vfLimited[NET_MAX] GUARDED_BY(cs_mapLocalHost) = {};
std::string strSubVersion;
void CConnman::AddOneShot(const std::string& strDest)
{
LOCK(cs_vOneShots);
vOneShots.push_back(strDest);
}
unsigned short GetListenPort()
{
return (unsigned short)(gArgs.GetArg("-port", Params().GetDefaultPort()));
}
// find 'best' local address for a particular peer
bool GetLocal(CService& addr, const CNetAddr *paddrPeer)
{
if (!fListen)
return false;
int nBestScore = -1;
int nBestReachability = -1;
{
LOCK(cs_mapLocalHost);
for (const auto& entry : mapLocalHost)
{
int nScore = entry.second.nScore;
int nReachability = entry.first.GetReachabilityFrom(paddrPeer);
if (nReachability > nBestReachability || (nReachability == nBestReachability && nScore > nBestScore))
{
addr = CService(entry.first, entry.second.nPort);
nBestReachability = nReachability;
nBestScore = nScore;
}
}
}
return nBestScore >= 0;
}
//! Convert the pnSeed6 array into usable address objects.
static std::vector<CAddress> convertSeed6(const std::vector<SeedSpec6> &vSeedsIn)
{
// It'll only connect to one or two seed nodes because once it connects,
// it'll get a pile of addresses with newer timestamps.
// Seed nodes are given a random 'last seen time' of between one and two
// weeks ago.
const int64_t nOneWeek = 7*24*60*60;
std::vector<CAddress> vSeedsOut;
vSeedsOut.reserve(vSeedsIn.size());
FastRandomContext rng;
for (const auto& seed_in : vSeedsIn) {
struct in6_addr ip;
memcpy(&ip, seed_in.addr, sizeof(ip));
CAddress addr(CService(ip, seed_in.port), GetDesirableServiceFlags(NODE_NONE));
addr.nTime = GetTime() - rng.randrange(nOneWeek) - nOneWeek;
vSeedsOut.push_back(addr);
}
return vSeedsOut;
}
// get best local address for a particular peer as a CAddress
// Otherwise, return the unroutable 0.0.0.0 but filled in with
// the normal parameters, since the IP may be changed to a useful
// one by discovery.
CAddress GetLocalAddress(const CNetAddr *paddrPeer, ServiceFlags nLocalServices)
{
CAddress ret(CService(CNetAddr(),GetListenPort()), nLocalServices);
CService addr;
if (GetLocal(addr, paddrPeer))
{
ret = CAddress(addr, nLocalServices);
}
ret.nTime = GetAdjustedTime();
return ret;
}
static int GetnScore(const CService& addr)
{
LOCK(cs_mapLocalHost);
if (mapLocalHost.count(addr) == 0) return 0;
return mapLocalHost[addr].nScore;
}
// Is our peer's addrLocal potentially useful as an external IP source?
bool IsPeerAddrLocalGood(CNode *pnode)
{
CService addrLocal = pnode->GetAddrLocal();
return fDiscover && pnode->addr.IsRoutable() && addrLocal.IsRoutable() &&
IsReachable(addrLocal.GetNetwork());
}
// pushes our own address to a peer
void AdvertiseLocal(CNode *pnode)
{
if (fListen && pnode->fSuccessfullyConnected)
{
CAddress addrLocal = GetLocalAddress(&pnode->addr, pnode->GetLocalServices());
if (gArgs.GetBoolArg("-addrmantest", false)) {
// use IPv4 loopback during addrmantest
addrLocal = CAddress(CService(LookupNumeric("127.0.0.1", GetListenPort())), pnode->GetLocalServices());
}
// If discovery is enabled, sometimes give our peer the address it
// tells us that it sees us as in case it has a better idea of our
// address than we do.
FastRandomContext rng;
if (IsPeerAddrLocalGood(pnode) && (!addrLocal.IsRoutable() ||
rng.randbits((GetnScore(addrLocal) > LOCAL_MANUAL) ? 3 : 1) == 0))
{
addrLocal.SetIP(pnode->GetAddrLocal());
}
if (addrLocal.IsRoutable() || gArgs.GetBoolArg("-addrmantest", false))
{
LogPrint(BCLog::NET, "AdvertiseLocal: advertising address %s\n", addrLocal.ToString());
pnode->PushAddress(addrLocal, rng);
}
}
}
// learn a new local address
bool AddLocal(const CService& addr, int nScore)
{
if (!addr.IsRoutable())
return false;
if (!fDiscover && nScore < LOCAL_MANUAL)
return false;
if (!IsReachable(addr))
return false;
LogPrintf("AddLocal(%s,%i)\n", addr.ToString(), nScore);
{
LOCK(cs_mapLocalHost);
bool fAlready = mapLocalHost.count(addr) > 0;
LocalServiceInfo &info = mapLocalHost[addr];
if (!fAlready || nScore >= info.nScore) {
info.nScore = nScore + (fAlready ? 1 : 0);
info.nPort = addr.GetPort();
}
}
return true;
}
bool AddLocal(const CNetAddr &addr, int nScore)
{
return AddLocal(CService(addr, GetListenPort()), nScore);
}
void RemoveLocal(const CService& addr)
{
LOCK(cs_mapLocalHost);
LogPrintf("RemoveLocal(%s)\n", addr.ToString());
mapLocalHost.erase(addr);
}
void SetReachable(enum Network net, bool reachable)
{
if (net == NET_UNROUTABLE || net == NET_INTERNAL)
return;
LOCK(cs_mapLocalHost);
vfLimited[net] = !reachable;
}
bool IsReachable(enum Network net)
{
LOCK(cs_mapLocalHost);
return !vfLimited[net];
}
bool IsReachable(const CNetAddr &addr)
{
return IsReachable(addr.GetNetwork());
}
/** vote for a local address */
bool SeenLocal(const CService& addr)
{
{
LOCK(cs_mapLocalHost);
if (mapLocalHost.count(addr) == 0)
return false;
mapLocalHost[addr].nScore++;
}
return true;
}
/** check whether a given address is potentially local */
bool IsLocal(const CService& addr)
{
LOCK(cs_mapLocalHost);
return mapLocalHost.count(addr) > 0;
}
CNode* CConnman::FindNode(const CNetAddr& ip)
{
LOCK(cs_vNodes);
for (CNode* pnode : vNodes) {
if (static_cast<CNetAddr>(pnode->addr) == ip) {
return pnode;
}
}
return nullptr;
}
CNode* CConnman::FindNode(const CSubNet& subNet)
{
LOCK(cs_vNodes);
for (CNode* pnode : vNodes) {
if (subNet.Match(static_cast<CNetAddr>(pnode->addr))) {
return pnode;
}
}
return nullptr;
}
CNode* CConnman::FindNode(const std::string& addrName)
{
LOCK(cs_vNodes);
for (CNode* pnode : vNodes) {
if (pnode->GetAddrName() == addrName) {
return pnode;
}
}
return nullptr;
}
CNode* CConnman::FindNode(const CService& addr)
{
LOCK(cs_vNodes);
for (CNode* pnode : vNodes) {
if (static_cast<CService>(pnode->addr) == addr) {
return pnode;
}
}
return nullptr;
}
bool CConnman::CheckIncomingNonce(uint64_t nonce)
{
LOCK(cs_vNodes);
for (const CNode* pnode : vNodes) {
if (!pnode->fSuccessfullyConnected && !pnode->fInbound && pnode->GetLocalNonce() == nonce)
return false;
}
return true;
}
/** Get the bind address for a socket as CAddress */
static CAddress GetBindAddress(SOCKET sock)
{
CAddress addr_bind;
struct sockaddr_storage sockaddr_bind;
socklen_t sockaddr_bind_len = sizeof(sockaddr_bind);
if (sock != INVALID_SOCKET) {
if (!getsockname(sock, (struct sockaddr*)&sockaddr_bind, &sockaddr_bind_len)) {
addr_bind.SetSockAddr((const struct sockaddr*)&sockaddr_bind);
} else {
LogPrint(BCLog::NET, "Warning: getsockname failed\n");
}
}
return addr_bind;
}
CNode* CConnman::ConnectNode(CAddress addrConnect, const char *pszDest, bool fCountFailure, bool manual_connection)
{
if (pszDest == nullptr) {
if (IsLocal(addrConnect))
return nullptr;
// Look for an existing connection
CNode* pnode = FindNode(static_cast<CService>(addrConnect));
if (pnode)
{
LogPrintf("Failed to open new connection, already connected\n");
return nullptr;
}
}
/// debug print
LogPrint(BCLog::NET, "trying connection %s lastseen=%.1fhrs\n",
pszDest ? pszDest : addrConnect.ToString(),
pszDest ? 0.0 : (double)(GetAdjustedTime() - addrConnect.nTime)/3600.0);
// Resolve
const int default_port = Params().GetDefaultPort();
if (pszDest) {
std::vector<CService> resolved;
if (Lookup(pszDest, resolved, default_port, fNameLookup && !HaveNameProxy(), 256) && !resolved.empty()) {
addrConnect = CAddress(resolved[GetRand(resolved.size())], NODE_NONE);
if (!addrConnect.IsValid()) {
LogPrint(BCLog::NET, "Resolver returned invalid address %s for %s\n", addrConnect.ToString(), pszDest);
return nullptr;
}
// It is possible that we already have a connection to the IP/port pszDest resolved to.
// In that case, drop the connection that was just created, and return the existing CNode instead.
// Also store the name we used to connect in that CNode, so that future FindNode() calls to that
// name catch this early.
LOCK(cs_vNodes);
CNode* pnode = FindNode(static_cast<CService>(addrConnect));
if (pnode)
{
pnode->MaybeSetAddrName(std::string(pszDest));
LogPrintf("Failed to open new connection, already connected\n");
return nullptr;
}
}
}
// Connect
bool connected = false;
SOCKET hSocket = INVALID_SOCKET;
proxyType proxy;
if (addrConnect.IsValid()) {
bool proxyConnectionFailed = false;
if (GetProxy(addrConnect.GetNetwork(), proxy)) {
hSocket = CreateSocket(proxy.proxy);
if (hSocket == INVALID_SOCKET) {
return nullptr;
}
connected = ConnectThroughProxy(proxy, addrConnect.ToStringIP(), addrConnect.GetPort(), hSocket, nConnectTimeout, &proxyConnectionFailed);
} else {
// no proxy needed (none set for target network)
hSocket = CreateSocket(addrConnect);
if (hSocket == INVALID_SOCKET) {
return nullptr;
}
connected = ConnectSocketDirectly(addrConnect, hSocket, nConnectTimeout, manual_connection);
}
if (!proxyConnectionFailed) {
// If a connection to the node was attempted, and failure (if any) is not caused by a problem connecting to
// the proxy, mark this as an attempt.
addrman.Attempt(addrConnect, fCountFailure);
}
} else if (pszDest && GetNameProxy(proxy)) {
hSocket = CreateSocket(proxy.proxy);
if (hSocket == INVALID_SOCKET) {
return nullptr;
}
std::string host;
int port = default_port;
SplitHostPort(std::string(pszDest), port, host);
connected = ConnectThroughProxy(proxy, host, port, hSocket, nConnectTimeout, nullptr);
}
if (!connected) {
CloseSocket(hSocket);
return nullptr;
}
// Add node
NodeId id = GetNewNodeId();
uint64_t nonce = GetDeterministicRandomizer(RANDOMIZER_ID_LOCALHOSTNONCE).Write(id).Finalize();
CAddress addr_bind = GetBindAddress(hSocket);
CNode* pnode = new CNode(id, nLocalServices, GetBestHeight(), hSocket, addrConnect, CalculateKeyedNetGroup(addrConnect), nonce, addr_bind, pszDest ? pszDest : "", false);
pnode->AddRef();
return pnode;
}
void CNode::CloseSocketDisconnect()
{
fDisconnect = true;
LOCK(cs_hSocket);
if (hSocket != INVALID_SOCKET)
{
LogPrint(BCLog::NET, "disconnecting peer=%d\n", id);
CloseSocket(hSocket);
}
}
bool CConnman::IsWhitelistedRange(const CNetAddr &addr) {
for (const CSubNet& subnet : vWhitelistedRange) {
if (subnet.Match(addr))
return true;
}
return false;
}
std::string CNode::GetAddrName() const {
LOCK(cs_addrName);
return addrName;
}
void CNode::MaybeSetAddrName(const std::string& addrNameIn) {
LOCK(cs_addrName);
if (addrName.empty()) {
addrName = addrNameIn;
}
}
CService CNode::GetAddrLocal() const {
LOCK(cs_addrLocal);
return addrLocal;
}
void CNode::SetAddrLocal(const CService& addrLocalIn) {
LOCK(cs_addrLocal);
if (addrLocal.IsValid()) {
error("Addr local already set for node: %i. Refusing to change from %s to %s", id, addrLocal.ToString(), addrLocalIn.ToString());
} else {
addrLocal = addrLocalIn;
}
}
#undef X
#define X(name) stats.name = name
void CNode::copyStats(CNodeStats &stats)
{
stats.nodeid = this->GetId();
X(nServices);
X(addr);
X(addrBind);
{
LOCK(cs_filter);
X(fRelayTxes);
}
X(nLastSend);
X(nLastRecv);
X(nTimeConnected);
X(nTimeOffset);
stats.addrName = GetAddrName();
X(nVersion);
{
LOCK(cs_SubVer);
X(cleanSubVer);
}
X(fInbound);
X(m_manual_connection);
X(nStartingHeight);
{
LOCK(cs_vSend);
X(mapSendBytesPerMsgCmd);
X(nSendBytes);
}
{
LOCK(cs_vRecv);
X(mapRecvBytesPerMsgCmd);
X(nRecvBytes);
}
X(fWhitelisted);
{
LOCK(cs_feeFilter);
X(minFeeFilter);
}
// It is common for nodes with good ping times to suddenly become lagged,
// due to a new block arriving or other large transfer.
// Merely reporting pingtime might fool the caller into thinking the node was still responsive,
// since pingtime does not update until the ping is complete, which might take a while.
// So, if a ping is taking an unusually long time in flight,
// the caller can immediately detect that this is happening.
int64_t nPingUsecWait = 0;
if ((0 != nPingNonceSent) && (0 != nPingUsecStart)) {
nPingUsecWait = GetTimeMicros() - nPingUsecStart;
}
// Raw ping time is in microseconds, but show it to user as whole seconds (Bitcoin users should be well used to small numbers with many decimal places by now :)
stats.dPingTime = (((double)nPingUsecTime) / 1e6);
stats.dMinPing = (((double)nMinPingUsecTime) / 1e6);
stats.dPingWait = (((double)nPingUsecWait) / 1e6);
// Leave string empty if addrLocal invalid (not filled in yet)
CService addrLocalUnlocked = GetAddrLocal();
stats.addrLocal = addrLocalUnlocked.IsValid() ? addrLocalUnlocked.ToString() : "";
}
#undef X
bool CNode::ReceiveMsgBytes(const char *pch, unsigned int nBytes, bool& complete)
{
complete = false;
int64_t nTimeMicros = GetTimeMicros();
LOCK(cs_vRecv);
nLastRecv = nTimeMicros / 1000000;
nRecvBytes += nBytes;
while (nBytes > 0) {
// get current incomplete message, or create a new one
if (vRecvMsg.empty() ||
vRecvMsg.back().complete())
vRecvMsg.push_back(CNetMessage(Params().MessageStart(), SER_NETWORK, INIT_PROTO_VERSION));
CNetMessage& msg = vRecvMsg.back();
// absorb network data
int handled;
if (!msg.in_data)
handled = msg.readHeader(pch, nBytes);
else
handled = msg.readData(pch, nBytes);
if (handled < 0)
return false;
if (msg.in_data && msg.hdr.nMessageSize > MAX_PROTOCOL_MESSAGE_LENGTH) {
LogPrint(BCLog::NET, "Oversized message from peer=%i, disconnecting\n", GetId());
return false;
}
pch += handled;
nBytes -= handled;
if (msg.complete()) {
//store received bytes per message command
//to prevent a memory DOS, only allow valid commands
mapMsgCmdSize::iterator i = mapRecvBytesPerMsgCmd.find(msg.hdr.pchCommand);
if (i == mapRecvBytesPerMsgCmd.end())
i = mapRecvBytesPerMsgCmd.find(NET_MESSAGE_COMMAND_OTHER);
assert(i != mapRecvBytesPerMsgCmd.end());
i->second += msg.hdr.nMessageSize + CMessageHeader::HEADER_SIZE;
msg.nTime = nTimeMicros;
complete = true;
}
}
return true;
}
void CNode::SetSendVersion(int nVersionIn)
{
// Send version may only be changed in the version message, and
// only one version message is allowed per session. We can therefore
// treat this value as const and even atomic as long as it's only used
// once a version message has been successfully processed. Any attempt to
// set this twice is an error.
if (nSendVersion != 0) {
error("Send version already set for node: %i. Refusing to change from %i to %i", id, nSendVersion, nVersionIn);
} else {
nSendVersion = nVersionIn;
}
}
int CNode::GetSendVersion() const
{
// The send version should always be explicitly set to
// INIT_PROTO_VERSION rather than using this value until SetSendVersion
// has been called.
if (nSendVersion == 0) {
error("Requesting unset send version for node: %i. Using %i", id, INIT_PROTO_VERSION);
return INIT_PROTO_VERSION;
}
return nSendVersion;
}
int CNetMessage::readHeader(const char *pch, unsigned int nBytes)
{
// copy data to temporary parsing buffer
unsigned int nRemaining = 24 - nHdrPos;
unsigned int nCopy = std::min(nRemaining, nBytes);
memcpy(&hdrbuf[nHdrPos], pch, nCopy);
nHdrPos += nCopy;
// if header incomplete, exit
if (nHdrPos < 24)
return nCopy;
// deserialize to CMessageHeader
try {
hdrbuf >> hdr;
}
catch (const std::exception&) {
return -1;
}
// reject messages larger than MAX_SIZE
if (hdr.nMessageSize > MAX_SIZE)
return -1;
// switch state to reading message data
in_data = true;
return nCopy;
}
int CNetMessage::readData(const char *pch, unsigned int nBytes)
{
unsigned int nRemaining = hdr.nMessageSize - nDataPos;
unsigned int nCopy = std::min(nRemaining, nBytes);
if (vRecv.size() < nDataPos + nCopy) {
// Allocate up to 256 KiB ahead, but never more than the total message size.
vRecv.resize(std::min(hdr.nMessageSize, nDataPos + nCopy + 256 * 1024));
}
hasher.Write((const unsigned char*)pch, nCopy);
memcpy(&vRecv[nDataPos], pch, nCopy);
nDataPos += nCopy;
return nCopy;
}
const uint256& CNetMessage::GetMessageHash() const
{
assert(complete());
if (data_hash.IsNull())
hasher.Finalize(data_hash.begin());
return data_hash;
}
size_t CConnman::SocketSendData(CNode *pnode) const EXCLUSIVE_LOCKS_REQUIRED(pnode->cs_vSend)
{
auto it = pnode->vSendMsg.begin();
size_t nSentSize = 0;
while (it != pnode->vSendMsg.end()) {
const auto &data = *it;
assert(data.size() > pnode->nSendOffset);
int nBytes = 0;
{
LOCK(pnode->cs_hSocket);
if (pnode->hSocket == INVALID_SOCKET)
break;
nBytes = send(pnode->hSocket, reinterpret_cast<const char*>(data.data()) + pnode->nSendOffset, data.size() - pnode->nSendOffset, MSG_NOSIGNAL | MSG_DONTWAIT);
}
if (nBytes > 0) {
pnode->nLastSend = GetSystemTimeInSeconds();
pnode->nSendBytes += nBytes;
pnode->nSendOffset += nBytes;
nSentSize += nBytes;
if (pnode->nSendOffset == data.size()) {
pnode->nSendOffset = 0;
pnode->nSendSize -= data.size();
pnode->fPauseSend = pnode->nSendSize > nSendBufferMaxSize;
it++;
} else {
// could not send full message; stop sending more
break;
}
} else {
if (nBytes < 0) {
// error
int nErr = WSAGetLastError();
if (nErr != WSAEWOULDBLOCK && nErr != WSAEMSGSIZE && nErr != WSAEINTR && nErr != WSAEINPROGRESS)
{
LogPrintf("socket send error %s\n", NetworkErrorString(nErr));
pnode->CloseSocketDisconnect();
}
}
// couldn't send anything at all
break;
}
}
if (it == pnode->vSendMsg.end()) {
assert(pnode->nSendOffset == 0);
assert(pnode->nSendSize == 0);
}
pnode->vSendMsg.erase(pnode->vSendMsg.begin(), it);
return nSentSize;
}
struct NodeEvictionCandidate
{
NodeId id;
int64_t nTimeConnected;
int64_t nMinPingUsecTime;
int64_t nLastBlockTime;
int64_t nLastTXTime;
bool fRelevantServices;
bool fRelayTxes;
bool fBloomFilter;
CAddress addr;
uint64_t nKeyedNetGroup;
bool prefer_evict;
};
static bool ReverseCompareNodeMinPingTime(const NodeEvictionCandidate &a, const NodeEvictionCandidate &b)
{
return a.nMinPingUsecTime > b.nMinPingUsecTime;
}
static bool ReverseCompareNodeTimeConnected(const NodeEvictionCandidate &a, const NodeEvictionCandidate &b)
{
return a.nTimeConnected > b.nTimeConnected;
}
static bool CompareNetGroupKeyed(const NodeEvictionCandidate &a, const NodeEvictionCandidate &b) {
return a.nKeyedNetGroup < b.nKeyedNetGroup;
}
static bool CompareNodeBlockTime(const NodeEvictionCandidate &a, const NodeEvictionCandidate &b)
{
// There is a fall-through here because it is common for a node to have many peers which have not yet relayed a block.
if (a.nLastBlockTime != b.nLastBlockTime) return a.nLastBlockTime < b.nLastBlockTime;
if (a.fRelevantServices != b.fRelevantServices) return b.fRelevantServices;
return a.nTimeConnected > b.nTimeConnected;
}
static bool CompareNodeTXTime(const NodeEvictionCandidate &a, const NodeEvictionCandidate &b)
{
// There is a fall-through here because it is common for a node to have more than a few peers that have not yet relayed txn.
if (a.nLastTXTime != b.nLastTXTime) return a.nLastTXTime < b.nLastTXTime;
if (a.fRelayTxes != b.fRelayTxes) return b.fRelayTxes;
if (a.fBloomFilter != b.fBloomFilter) return a.fBloomFilter;
return a.nTimeConnected > b.nTimeConnected;
}
//! Sort an array by the specified comparator, then erase the last K elements.
template<typename T, typename Comparator>
static void EraseLastKElements(std::vector<T> &elements, Comparator comparator, size_t k)
{
std::sort(elements.begin(), elements.end(), comparator);
size_t eraseSize = std::min(k, elements.size());
elements.erase(elements.end() - eraseSize, elements.end());
}
/** Try to find a connection to evict when the node is full.
* Extreme care must be taken to avoid opening the node to attacker
* triggered network partitioning.
* The strategy used here is to protect a small number of peers
* for each of several distinct characteristics which are difficult
* to forge. In order to partition a node the attacker must be
* simultaneously better at all of them than honest peers.
*/
bool CConnman::AttemptToEvictConnection()
{
std::vector<NodeEvictionCandidate> vEvictionCandidates;
{
LOCK(cs_vNodes);
for (const CNode* node : vNodes) {
if (node->fWhitelisted)
continue;
if (!node->fInbound)
continue;
if (node->fDisconnect)
continue;
LOCK(node->cs_filter);
NodeEvictionCandidate candidate = {node->GetId(), node->nTimeConnected, node->nMinPingUsecTime,
node->nLastBlockTime, node->nLastTXTime,
HasAllDesirableServiceFlags(node->nServices),
node->fRelayTxes, node->pfilter != nullptr, node->addr, node->nKeyedNetGroup,
node->m_prefer_evict};
vEvictionCandidates.push_back(candidate);
}
}
// Protect connections with certain characteristics
// Deterministically select 4 peers to protect by netgroup.
// An attacker cannot predict which netgroups will be protected
EraseLastKElements(vEvictionCandidates, CompareNetGroupKeyed, 4);
// Protect the 8 nodes with the lowest minimum ping time.
// An attacker cannot manipulate this metric without physically moving nodes closer to the target.
EraseLastKElements(vEvictionCandidates, ReverseCompareNodeMinPingTime, 8);
// Protect 4 nodes that most recently sent us transactions.
// An attacker cannot manipulate this metric without performing useful work.
EraseLastKElements(vEvictionCandidates, CompareNodeTXTime, 4);
// Protect 4 nodes that most recently sent us blocks.
// An attacker cannot manipulate this metric without performing useful work.
EraseLastKElements(vEvictionCandidates, CompareNodeBlockTime, 4);
// Protect the half of the remaining nodes which have been connected the longest.
// This replicates the non-eviction implicit behavior, and precludes attacks that start later.
EraseLastKElements(vEvictionCandidates, ReverseCompareNodeTimeConnected, vEvictionCandidates.size() / 2);
if (vEvictionCandidates.empty()) return false;
// If any remaining peers are preferred for eviction consider only them.
// This happens after the other preferences since if a peer is really the best by other criteria (esp relaying blocks)
// then we probably don't want to evict it no matter what.
if (std::any_of(vEvictionCandidates.begin(),vEvictionCandidates.end(),[](NodeEvictionCandidate const &n){return n.prefer_evict;})) {
vEvictionCandidates.erase(std::remove_if(vEvictionCandidates.begin(),vEvictionCandidates.end(),
[](NodeEvictionCandidate const &n){return !n.prefer_evict;}),vEvictionCandidates.end());
}
// Identify the network group with the most connections and youngest member.
// (vEvictionCandidates is already sorted by reverse connect time)
uint64_t naMostConnections;
unsigned int nMostConnections = 0;
int64_t nMostConnectionsTime = 0;
std::map<uint64_t, std::vector<NodeEvictionCandidate> > mapNetGroupNodes;
for (const NodeEvictionCandidate &node : vEvictionCandidates) {
std::vector<NodeEvictionCandidate> &group = mapNetGroupNodes[node.nKeyedNetGroup];
group.push_back(node);
int64_t grouptime = group[0].nTimeConnected;
if (group.size() > nMostConnections || (group.size() == nMostConnections && grouptime > nMostConnectionsTime)) {
nMostConnections = group.size();
nMostConnectionsTime = grouptime;
naMostConnections = node.nKeyedNetGroup;
}
}
// Reduce to the network group with the most connections
vEvictionCandidates = std::move(mapNetGroupNodes[naMostConnections]);
// Disconnect from the network group with the most connections
NodeId evicted = vEvictionCandidates.front().id;
LOCK(cs_vNodes);
for (CNode* pnode : vNodes) {
if (pnode->GetId() == evicted) {
pnode->fDisconnect = true;
return true;
}
}
return false;
}
void CConnman::AcceptConnection(const ListenSocket& hListenSocket) {
struct sockaddr_storage sockaddr;
socklen_t len = sizeof(sockaddr);
SOCKET hSocket = accept(hListenSocket.socket, (struct sockaddr*)&sockaddr, &len);
CAddress addr;
int nInbound = 0;
int nMaxInbound = nMaxConnections - (nMaxOutbound + nMaxFeeler);
if (hSocket != INVALID_SOCKET) {
if (!addr.SetSockAddr((const struct sockaddr*)&sockaddr)) {
LogPrintf("Warning: Unknown socket family\n");
}
}
bool whitelisted = hListenSocket.whitelisted || IsWhitelistedRange(addr);
{
LOCK(cs_vNodes);
for (const CNode* pnode : vNodes) {
if (pnode->fInbound) nInbound++;
}
}
if (hSocket == INVALID_SOCKET)
{
int nErr = WSAGetLastError();
if (nErr != WSAEWOULDBLOCK)
LogPrintf("socket error accept failed: %s\n", NetworkErrorString(nErr));
return;
}
if (!fNetworkActive) {
LogPrintf("connection from %s dropped: not accepting new connections\n", addr.ToString());
CloseSocket(hSocket);
return;
}
if (!IsSelectableSocket(hSocket))
{
LogPrintf("connection from %s dropped: non-selectable socket\n", addr.ToString());
CloseSocket(hSocket);
return;
}
// According to the internet TCP_NODELAY is not carried into accepted sockets
// on all platforms. Set it again here just to be sure.
SetSocketNoDelay(hSocket);
int bannedlevel = m_banman ? m_banman->IsBannedLevel(addr) : 0;
// Don't accept connections from banned peers, but if our inbound slots aren't almost full, accept
// if the only banning reason was an automatic misbehavior ban.
if (!whitelisted && bannedlevel > ((nInbound + 1 < nMaxInbound) ? 1 : 0))
{
LogPrint(BCLog::NET, "connection from %s dropped (banned)\n", addr.ToString());
CloseSocket(hSocket);
return;
}
if (nInbound >= nMaxInbound)
{
if (!AttemptToEvictConnection()) {
// No connection to evict, disconnect the new connection
LogPrint(BCLog::NET, "failed to find an eviction candidate - connection dropped (full)\n");
CloseSocket(hSocket);
return;
}
}
NodeId id = GetNewNodeId();
uint64_t nonce = GetDeterministicRandomizer(RANDOMIZER_ID_LOCALHOSTNONCE).Write(id).Finalize();
CAddress addr_bind = GetBindAddress(hSocket);
CNode* pnode = new CNode(id, nLocalServices, GetBestHeight(), hSocket, addr, CalculateKeyedNetGroup(addr), nonce, addr_bind, "", true);
pnode->AddRef();
pnode->fWhitelisted = whitelisted;
pnode->m_prefer_evict = bannedlevel > 0;
m_msgproc->InitializeNode(pnode);
LogPrint(BCLog::NET, "connection from %s accepted\n", addr.ToString());
{
LOCK(cs_vNodes);
vNodes.push_back(pnode);
}
}
void CConnman::DisconnectNodes()
{
{
LOCK(cs_vNodes);
if (!fNetworkActive) {
// Disconnect any connected nodes
for (CNode* pnode : vNodes) {
if (!pnode->fDisconnect) {
LogPrint(BCLog::NET, "Network not active, dropping peer=%d\n", pnode->GetId());
pnode->fDisconnect = true;
}
}
}
// Disconnect unused nodes
std::vector<CNode*> vNodesCopy = vNodes;
for (CNode* pnode : vNodesCopy)
{
if (pnode->fDisconnect)
{
// remove from vNodes
vNodes.erase(remove(vNodes.begin(), vNodes.end(), pnode), vNodes.end());
// release outbound grant (if any)
pnode->grantOutbound.Release();
// close socket and cleanup
pnode->CloseSocketDisconnect();
// hold in disconnected pool until all refs are released
pnode->Release();
vNodesDisconnected.push_back(pnode);
}
}
}
{
// Delete disconnected nodes
std::list<CNode*> vNodesDisconnectedCopy = vNodesDisconnected;
for (CNode* pnode : vNodesDisconnectedCopy)
{
// wait until threads are done using it
if (pnode->GetRefCount() <= 0) {
bool fDelete = false;
{
TRY_LOCK(pnode->cs_inventory, lockInv);
if (lockInv) {
TRY_LOCK(pnode->cs_vSend, lockSend);
if (lockSend) {
fDelete = true;
}
}
}
if (fDelete) {
vNodesDisconnected.remove(pnode);
DeleteNode(pnode);
}
}
}
}
}
void CConnman::NotifyNumConnectionsChanged()
{
size_t vNodesSize;
{
LOCK(cs_vNodes);
vNodesSize = vNodes.size();
}
if(vNodesSize != nPrevNodeCount) {
nPrevNodeCount = vNodesSize;
if(clientInterface)
clientInterface->NotifyNumConnectionsChanged(vNodesSize);
}
}
void CConnman::InactivityCheck(CNode *pnode)
{
int64_t nTime = GetSystemTimeInSeconds();
if (nTime - pnode->nTimeConnected > m_peer_connect_timeout)
{
if (pnode->nLastRecv == 0 || pnode->nLastSend == 0)
{
LogPrint(BCLog::NET, "socket no message in first %i seconds, %d %d from %d\n", m_peer_connect_timeout, pnode->nLastRecv != 0, pnode->nLastSend != 0, pnode->GetId());
pnode->fDisconnect = true;
}
else if (nTime - pnode->nLastSend > TIMEOUT_INTERVAL)
{
LogPrintf("socket sending timeout: %is\n", nTime - pnode->nLastSend);
pnode->fDisconnect = true;
}
else if (nTime - pnode->nLastRecv > (pnode->nVersion > BIP0031_VERSION ? TIMEOUT_INTERVAL : 90*60))
{
LogPrintf("socket receive timeout: %is\n", nTime - pnode->nLastRecv);
pnode->fDisconnect = true;
}
else if (pnode->nPingNonceSent && pnode->nPingUsecStart + TIMEOUT_INTERVAL * 1000000 < GetTimeMicros())
{
LogPrintf("ping timeout: %fs\n", 0.000001 * (GetTimeMicros() - pnode->nPingUsecStart));
pnode->fDisconnect = true;
}
else if (!pnode->fSuccessfullyConnected)
{
LogPrint(BCLog::NET, "version handshake timeout from %d\n", pnode->GetId());
pnode->fDisconnect = true;
}
}
}
bool CConnman::GenerateSelectSet(std::set<SOCKET> &recv_set, std::set<SOCKET> &send_set, std::set<SOCKET> &error_set)
{
for (const ListenSocket& hListenSocket : vhListenSocket) {
recv_set.insert(hListenSocket.socket);
}
{
LOCK(cs_vNodes);
for (CNode* pnode : vNodes)
{
// Implement the following logic:
// * If there is data to send, select() for sending data. As this only
// happens when optimistic write failed, we choose to first drain the
// write buffer in this case before receiving more. This avoids
// needlessly queueing received data, if the remote peer is not themselves
// receiving data. This means properly utilizing TCP flow control signalling.
// * Otherwise, if there is space left in the receive buffer, select() for
// receiving data.
// * Hand off all complete messages to the processor, to be handled without
// blocking here.
bool select_recv = !pnode->fPauseRecv;
bool select_send;
{
LOCK(pnode->cs_vSend);
select_send = !pnode->vSendMsg.empty();
}
LOCK(pnode->cs_hSocket);
if (pnode->hSocket == INVALID_SOCKET)
continue;
error_set.insert(pnode->hSocket);
if (select_send) {
send_set.insert(pnode->hSocket);
continue;
}
if (select_recv) {
recv_set.insert(pnode->hSocket);
}
}
}
return !recv_set.empty() || !send_set.empty() || !error_set.empty();
}
#ifdef USE_POLL
void CConnman::SocketEvents(std::set<SOCKET> &recv_set, std::set<SOCKET> &send_set, std::set<SOCKET> &error_set)
{
std::set<SOCKET> recv_select_set, send_select_set, error_select_set;
if (!GenerateSelectSet(recv_select_set, send_select_set, error_select_set)) {
interruptNet.sleep_for(std::chrono::milliseconds(SELECT_TIMEOUT_MILLISECONDS));
return;
}
std::unordered_map<SOCKET, struct pollfd> pollfds;
for (SOCKET socket_id : recv_select_set) {
pollfds[socket_id].fd = socket_id;
pollfds[socket_id].events |= POLLIN;
}
for (SOCKET socket_id : send_select_set) {
pollfds[socket_id].fd = socket_id;
pollfds[socket_id].events |= POLLOUT;
}
for (SOCKET socket_id : error_select_set) {
pollfds[socket_id].fd = socket_id;
// These flags are ignored, but we set them for clarity
pollfds[socket_id].events |= POLLERR|POLLHUP;
}
std::vector<struct pollfd> vpollfds;
vpollfds.reserve(pollfds.size());
for (auto it : pollfds) {
vpollfds.push_back(std::move(it.second));
}
if (poll(vpollfds.data(), vpollfds.size(), SELECT_TIMEOUT_MILLISECONDS) < 0) return;
if (interruptNet) return;
for (struct pollfd pollfd_entry : vpollfds) {
if (pollfd_entry.revents & POLLIN) recv_set.insert(pollfd_entry.fd);
if (pollfd_entry.revents & POLLOUT) send_set.insert(pollfd_entry.fd);
if (pollfd_entry.revents & (POLLERR|POLLHUP)) error_set.insert(pollfd_entry.fd);
}
}
#else
void CConnman::SocketEvents(std::set<SOCKET> &recv_set, std::set<SOCKET> &send_set, std::set<SOCKET> &error_set)
{
std::set<SOCKET> recv_select_set, send_select_set, error_select_set;
if (!GenerateSelectSet(recv_select_set, send_select_set, error_select_set)) {
interruptNet.sleep_for(std::chrono::milliseconds(SELECT_TIMEOUT_MILLISECONDS));
return;
}
//
// Find which sockets have data to receive
//
struct timeval timeout;
timeout.tv_sec = 0;
timeout.tv_usec = SELECT_TIMEOUT_MILLISECONDS * 1000; // frequency to poll pnode->vSend
fd_set fdsetRecv;
fd_set fdsetSend;
fd_set fdsetError;
FD_ZERO(&fdsetRecv);
FD_ZERO(&fdsetSend);
FD_ZERO(&fdsetError);
SOCKET hSocketMax = 0;
for (SOCKET hSocket : recv_select_set) {
FD_SET(hSocket, &fdsetRecv);
hSocketMax = std::max(hSocketMax, hSocket);
}
for (SOCKET hSocket : send_select_set) {
FD_SET(hSocket, &fdsetSend);
hSocketMax = std::max(hSocketMax, hSocket);
}
for (SOCKET hSocket : error_select_set) {
FD_SET(hSocket, &fdsetError);
hSocketMax = std::max(hSocketMax, hSocket);
}
int nSelect = select(hSocketMax + 1, &fdsetRecv, &fdsetSend, &fdsetError, &timeout);
if (interruptNet)
return;
if (nSelect == SOCKET_ERROR)
{
int nErr = WSAGetLastError();
LogPrintf("socket select error %s\n", NetworkErrorString(nErr));
for (unsigned int i = 0; i <= hSocketMax; i++)
FD_SET(i, &fdsetRecv);
FD_ZERO(&fdsetSend);
FD_ZERO(&fdsetError);
if (!interruptNet.sleep_for(std::chrono::milliseconds(SELECT_TIMEOUT_MILLISECONDS)))
return;
}
for (SOCKET hSocket : recv_select_set) {
if (FD_ISSET(hSocket, &fdsetRecv)) {
recv_set.insert(hSocket);
}
}
for (SOCKET hSocket : send_select_set) {
if (FD_ISSET(hSocket, &fdsetSend)) {
send_set.insert(hSocket);
}
}
for (SOCKET hSocket : error_select_set) {
if (FD_ISSET(hSocket, &fdsetError)) {
error_set.insert(hSocket);
}
}
}
#endif
void CConnman::SocketHandler()
{
std::set<SOCKET> recv_set, send_set, error_set;
SocketEvents(recv_set, send_set, error_set);
if (interruptNet) return;
//
// Accept new connections
//
for (const ListenSocket& hListenSocket : vhListenSocket)
{
if (hListenSocket.socket != INVALID_SOCKET && recv_set.count(hListenSocket.socket) > 0)
{
AcceptConnection(hListenSocket);
}
}
//
// Service each socket
//
std::vector<CNode*> vNodesCopy;
{
LOCK(cs_vNodes);
vNodesCopy = vNodes;
for (CNode* pnode : vNodesCopy)
pnode->AddRef();
}
for (CNode* pnode : vNodesCopy)
{
if (interruptNet)
return;
//
// Receive
//
bool recvSet = false;
bool sendSet = false;
bool errorSet = false;
{
LOCK(pnode->cs_hSocket);
if (pnode->hSocket == INVALID_SOCKET)
continue;
recvSet = recv_set.count(pnode->hSocket) > 0;
sendSet = send_set.count(pnode->hSocket) > 0;
errorSet = error_set.count(pnode->hSocket) > 0;
}
if (recvSet || errorSet)
{
// typical socket buffer is 8K-64K
char pchBuf[0x10000];
int nBytes = 0;
{
LOCK(pnode->cs_hSocket);
if (pnode->hSocket == INVALID_SOCKET)
continue;
nBytes = recv(pnode->hSocket, pchBuf, sizeof(pchBuf), MSG_DONTWAIT);
}
if (nBytes > 0)
{
bool notify = false;
if (!pnode->ReceiveMsgBytes(pchBuf, nBytes, notify))
pnode->CloseSocketDisconnect();
RecordBytesRecv(nBytes);
if (notify) {
size_t nSizeAdded = 0;
auto it(pnode->vRecvMsg.begin());
for (; it != pnode->vRecvMsg.end(); ++it) {
if (!it->complete())
break;
nSizeAdded += it->vRecv.size() + CMessageHeader::HEADER_SIZE;
}
{
LOCK(pnode->cs_vProcessMsg);
pnode->vProcessMsg.splice(pnode->vProcessMsg.end(), pnode->vRecvMsg, pnode->vRecvMsg.begin(), it);
pnode->nProcessQueueSize += nSizeAdded;
pnode->fPauseRecv = pnode->nProcessQueueSize > nReceiveFloodSize;
}
WakeMessageHandler();
}
}
else if (nBytes == 0)
{
// socket closed gracefully
if (!pnode->fDisconnect) {
LogPrint(BCLog::NET, "socket closed\n");
}
pnode->CloseSocketDisconnect();
}
else if (nBytes < 0)
{
// error
int nErr = WSAGetLastError();
if (nErr != WSAEWOULDBLOCK && nErr != WSAEMSGSIZE && nErr != WSAEINTR && nErr != WSAEINPROGRESS)
{
if (!pnode->fDisconnect)
LogPrintf("socket recv error %s\n", NetworkErrorString(nErr));
pnode->CloseSocketDisconnect();
}
}
}
//
// Send
//
if (sendSet)
{
LOCK(pnode->cs_vSend);
size_t nBytes = SocketSendData(pnode);
if (nBytes) {
RecordBytesSent(nBytes);
}
}
InactivityCheck(pnode);
}
{
LOCK(cs_vNodes);
for (CNode* pnode : vNodesCopy)
pnode->Release();
}
}
void CConnman::ThreadSocketHandler()
{
while (!interruptNet)
{
DisconnectNodes();
NotifyNumConnectionsChanged();
SocketHandler();
}
}
void CConnman::WakeMessageHandler()
{
{
std::lock_guard<std::mutex> lock(mutexMsgProc);
fMsgProcWake = true;
}
condMsgProc.notify_one();
}
#ifdef USE_UPNP
static CThreadInterrupt g_upnp_interrupt;
static std::thread g_upnp_thread;
static void ThreadMapPort()
{
std::string port = strprintf("%u", GetListenPort());
const char * multicastif = nullptr;
const char * minissdpdpath = nullptr;
struct UPNPDev * devlist = nullptr;
char lanaddr[64];
#ifndef UPNPDISCOVER_SUCCESS
/* miniupnpc 1.5 */
devlist = upnpDiscover(2000, multicastif, minissdpdpath, 0);
#elif MINIUPNPC_API_VERSION < 14
/* miniupnpc 1.6 */
int error = 0;
devlist = upnpDiscover(2000, multicastif, minissdpdpath, 0, 0, &error);
#else
/* miniupnpc 1.9.20150730 */
int error = 0;
devlist = upnpDiscover(2000, multicastif, minissdpdpath, 0, 0, 2, &error);
#endif
struct UPNPUrls urls;
struct IGDdatas data;
int r;
r = UPNP_GetValidIGD(devlist, &urls, &data, lanaddr, sizeof(lanaddr));
if (r == 1)
{
if (fDiscover) {
char externalIPAddress[40];
r = UPNP_GetExternalIPAddress(urls.controlURL, data.first.servicetype, externalIPAddress);
if(r != UPNPCOMMAND_SUCCESS)
LogPrintf("UPnP: GetExternalIPAddress() returned %d\n", r);
else
{
if(externalIPAddress[0])
{
CNetAddr resolved;
if(LookupHost(externalIPAddress, resolved, false)) {
LogPrintf("UPnP: ExternalIPAddress = %s\n", resolved.ToString().c_str());
AddLocal(resolved, LOCAL_UPNP);
}
}
else
LogPrintf("UPnP: GetExternalIPAddress failed.\n");
}
}
std::string strDesc = "Bitcoin " + FormatFullVersion();
do {
#ifndef UPNPDISCOVER_SUCCESS
/* miniupnpc 1.5 */
r = UPNP_AddPortMapping(urls.controlURL, data.first.servicetype,
port.c_str(), port.c_str(), lanaddr, strDesc.c_str(), "TCP", 0);
#else
/* miniupnpc 1.6 */
r = UPNP_AddPortMapping(urls.controlURL, data.first.servicetype,
port.c_str(), port.c_str(), lanaddr, strDesc.c_str(), "TCP", 0, "0");
#endif
if(r!=UPNPCOMMAND_SUCCESS)
LogPrintf("AddPortMapping(%s, %s, %s) failed with code %d (%s)\n",
port, port, lanaddr, r, strupnperror(r));
else
LogPrintf("UPnP Port Mapping successful.\n");
}
while(g_upnp_interrupt.sleep_for(std::chrono::minutes(20)));
r = UPNP_DeletePortMapping(urls.controlURL, data.first.servicetype, port.c_str(), "TCP", 0);
LogPrintf("UPNP_DeletePortMapping() returned: %d\n", r);
freeUPNPDevlist(devlist); devlist = nullptr;
FreeUPNPUrls(&urls);
} else {
LogPrintf("No valid UPnP IGDs found\n");
freeUPNPDevlist(devlist); devlist = nullptr;
if (r != 0)
FreeUPNPUrls(&urls);
}
}
void StartMapPort()
{
if (!g_upnp_thread.joinable()) {
assert(!g_upnp_interrupt);
g_upnp_thread = std::thread((std::bind(&TraceThread<void (*)()>, "upnp", &ThreadMapPort)));
}
}
void InterruptMapPort()
{
if(g_upnp_thread.joinable()) {
g_upnp_interrupt();
}
}
void StopMapPort()
{
if(g_upnp_thread.joinable()) {
g_upnp_thread.join();
g_upnp_interrupt.reset();
}
}
#else
void StartMapPort()
{
// Intentionally left blank.
}
void InterruptMapPort()
{
// Intentionally left blank.
}
void StopMapPort()
{
// Intentionally left blank.
}
#endif
void CConnman::ThreadDNSAddressSeed()
{
// goal: only query DNS seeds if address need is acute
// Avoiding DNS seeds when we don't need them improves user privacy by
// creating fewer identifying DNS requests, reduces trust by giving seeds
// less influence on the network topology, and reduces traffic to the seeds.
if ((addrman.size() > 0) &&
(!gArgs.GetBoolArg("-forcednsseed", DEFAULT_FORCEDNSSEED))) {
if (!interruptNet.sleep_for(std::chrono::seconds(11)))
return;
LOCK(cs_vNodes);
int nRelevant = 0;
for (const CNode* pnode : vNodes) {
nRelevant += pnode->fSuccessfullyConnected && !pnode->fFeeler && !pnode->fOneShot && !pnode->m_manual_connection && !pnode->fInbound;
}
if (nRelevant >= 2) {
LogPrintf("P2P peers available. Skipped DNS seeding.\n");
return;
}
}
const std::vector<std::string> &vSeeds = Params().DNSSeeds();
int found = 0;
LogPrintf("Loading addresses from DNS seeds (could take a while)\n");
for (const std::string &seed : vSeeds) {
if (interruptNet) {
return;
}
if (HaveNameProxy()) {
AddOneShot(seed);
} else {
std::vector<CNetAddr> vIPs;
std::vector<CAddress> vAdd;
ServiceFlags requiredServiceBits = GetDesirableServiceFlags(NODE_NONE);
std::string host = strprintf("x%x.%s", requiredServiceBits, seed);
CNetAddr resolveSource;
if (!resolveSource.SetInternal(host)) {
continue;
}
unsigned int nMaxIPs = 256; // Limits number of IPs learned from a DNS seed
if (LookupHost(host.c_str(), vIPs, nMaxIPs, true))
{
for (const CNetAddr& ip : vIPs)
{
int nOneDay = 24*3600;
CAddress addr = CAddress(CService(ip, Params().GetDefaultPort()), requiredServiceBits);
addr.nTime = GetTime() - 3*nOneDay - GetRand(4*nOneDay); // use a random age between 3 and 7 days old
vAdd.push_back(addr);
found++;
}
addrman.Add(vAdd, resolveSource);
} else {
// We now avoid directly using results from DNS Seeds which do not support service bit filtering,
// instead using them as a oneshot to get nodes with our desired service bits.
AddOneShot(seed);
}
}
}
LogPrintf("%d addresses found from DNS seeds\n", found);
}
void CConnman::DumpAddresses()
{
int64_t nStart = GetTimeMillis();
CAddrDB adb;
adb.Write(addrman);
LogPrint(BCLog::NET, "Flushed %d addresses to peers.dat %dms\n",
addrman.size(), GetTimeMillis() - nStart);
}
void CConnman::ProcessOneShot()
{
std::string strDest;
{
LOCK(cs_vOneShots);
if (vOneShots.empty())
return;
strDest = vOneShots.front();
vOneShots.pop_front();
}
CAddress addr;
CSemaphoreGrant grant(*semOutbound, true);
if (grant) {
OpenNetworkConnection(addr, false, &grant, strDest.c_str(), true);
}
}
bool CConnman::GetTryNewOutboundPeer()
{
return m_try_another_outbound_peer;
}
void CConnman::SetTryNewOutboundPeer(bool flag)
{
m_try_another_outbound_peer = flag;
LogPrint(BCLog::NET, "net: setting try another outbound peer=%s\n", flag ? "true" : "false");
}
// Return the number of peers we have over our outbound connection limit
// Exclude peers that are marked for disconnect, or are going to be
// disconnected soon (eg one-shots and feelers)
// Also exclude peers that haven't finished initial connection handshake yet
// (so that we don't decide we're over our desired connection limit, and then
// evict some peer that has finished the handshake)
int CConnman::GetExtraOutboundCount()
{
int nOutbound = 0;
{
LOCK(cs_vNodes);
for (const CNode* pnode : vNodes) {
if (!pnode->fInbound && !pnode->m_manual_connection && !pnode->fFeeler && !pnode->fDisconnect && !pnode->fOneShot && pnode->fSuccessfullyConnected) {
++nOutbound;
}
}
}
return std::max(nOutbound - nMaxOutbound, 0);
}
void CConnman::ThreadOpenConnections(const std::vector<std::string> connect)
{
// Connect to specific addresses
if (!connect.empty())
{
for (int64_t nLoop = 0;; nLoop++)
{
ProcessOneShot();
for (const std::string& strAddr : connect)
{
CAddress addr(CService(), NODE_NONE);
OpenNetworkConnection(addr, false, nullptr, strAddr.c_str(), false, false, true);
for (int i = 0; i < 10 && i < nLoop; i++)
{
if (!interruptNet.sleep_for(std::chrono::milliseconds(500)))
return;
}
}
if (!interruptNet.sleep_for(std::chrono::milliseconds(500)))
return;
}
}
// Initiate network connections
int64_t nStart = GetTime();
// Minimum time before next feeler connection (in microseconds).
int64_t nNextFeeler = PoissonNextSend(nStart*1000*1000, FEELER_INTERVAL);
while (!interruptNet)
{
ProcessOneShot();
if (!interruptNet.sleep_for(std::chrono::milliseconds(500)))
return;
CSemaphoreGrant grant(*semOutbound);
if (interruptNet)
return;
// Add seed nodes if DNS seeds are all down (an infrastructure attack?).
if (addrman.size() == 0 && (GetTime() - nStart > 60)) {
static bool done = false;
if (!done) {
LogPrintf("Adding fixed seed nodes as DNS doesn't seem to be available.\n");
CNetAddr local;
local.SetInternal("fixedseeds");
addrman.Add(convertSeed6(Params().FixedSeeds()), local);
done = true;
}
}
//
// Choose an address to connect to based on most recently seen
//
CAddress addrConnect;
// Only connect out to one peer per network group (/16 for IPv4).
int nOutbound = 0;
std::set<std::vector<unsigned char> > setConnected;
{
LOCK(cs_vNodes);
for (const CNode* pnode : vNodes) {
if (!pnode->fInbound && !pnode->m_manual_connection) {
// Netgroups for inbound and addnode peers are not excluded because our goal here
// is to not use multiple of our limited outbound slots on a single netgroup
// but inbound and addnode peers do not use our outbound slots. Inbound peers
// also have the added issue that they're attacker controlled and could be used
// to prevent us from connecting to particular hosts if we used them here.
setConnected.insert(pnode->addr.GetGroup());
nOutbound++;
}
}
}
// Feeler Connections
//
// Design goals:
// * Increase the number of connectable addresses in the tried table.
//
// Method:
// * Choose a random address from new and attempt to connect to it if we can connect
// successfully it is added to tried.
// * Start attempting feeler connections only after node finishes making outbound
// connections.
// * Only make a feeler connection once every few minutes.
//
bool fFeeler = false;
if (nOutbound >= nMaxOutbound && !GetTryNewOutboundPeer()) {
int64_t nTime = GetTimeMicros(); // The current time right now (in microseconds).
if (nTime > nNextFeeler) {
nNextFeeler = PoissonNextSend(nTime, FEELER_INTERVAL);
fFeeler = true;
} else {
continue;
}
}
addrman.ResolveCollisions();
int64_t nANow = GetAdjustedTime();
int nTries = 0;
while (!interruptNet)
{
CAddrInfo addr = addrman.SelectTriedCollision();
// SelectTriedCollision returns an invalid address if it is empty.
if (!fFeeler || !addr.IsValid()) {
addr = addrman.Select(fFeeler);
}
// Require outbound connections, other than feelers, to be to distinct network groups
if (!fFeeler && setConnected.count(addr.GetGroup())) {
break;
}
// if we selected an invalid or local address, restart
if (!addr.IsValid() || IsLocal(addr)) {
break;
}
// If we didn't find an appropriate destination after trying 100 addresses fetched from addrman,
// stop this loop, and let the outer loop run again (which sleeps, adds seed nodes, recalculates
// already-connected network ranges, ...) before trying new addrman addresses.
nTries++;
if (nTries > 100)
break;
if (!IsReachable(addr))
continue;
// only consider very recently tried nodes after 30 failed attempts
if (nANow - addr.nLastTry < 600 && nTries < 30)
continue;
// for non-feelers, require all the services we'll want,
// for feelers, only require they be a full node (only because most
// SPV clients don't have a good address DB available)
if (!fFeeler && !HasAllDesirableServiceFlags(addr.nServices)) {
continue;
} else if (fFeeler && !MayHaveUsefulAddressDB(addr.nServices)) {
continue;
}
// do not allow non-default ports, unless after 50 invalid addresses selected already
if (addr.GetPort() != Params().GetDefaultPort() && nTries < 50)
continue;
addrConnect = addr;
break;
}
if (addrConnect.IsValid()) {
if (fFeeler) {
// Add small amount of random noise before connection to avoid synchronization.
int randsleep = GetRandInt(FEELER_SLEEP_WINDOW * 1000);
if (!interruptNet.sleep_for(std::chrono::milliseconds(randsleep)))
return;
LogPrint(BCLog::NET, "Making feeler connection to %s\n", addrConnect.ToString());
}
OpenNetworkConnection(addrConnect, (int)setConnected.size() >= std::min(nMaxConnections - 1, 2), &grant, nullptr, false, fFeeler);
}
}
}
std::vector<AddedNodeInfo> CConnman::GetAddedNodeInfo()
{
std::vector<AddedNodeInfo> ret;
std::list<std::string> lAddresses(0);
{
LOCK(cs_vAddedNodes);
ret.reserve(vAddedNodes.size());
std::copy(vAddedNodes.cbegin(), vAddedNodes.cend(), std::back_inserter(lAddresses));
}
// Build a map of all already connected addresses (by IP:port and by name) to inbound/outbound and resolved CService
std::map<CService, bool> mapConnected;
std::map<std::string, std::pair<bool, CService>> mapConnectedByName;
{
LOCK(cs_vNodes);
for (const CNode* pnode : vNodes) {
if (pnode->addr.IsValid()) {
mapConnected[pnode->addr] = pnode->fInbound;
}
std::string addrName = pnode->GetAddrName();
if (!addrName.empty()) {
mapConnectedByName[std::move(addrName)] = std::make_pair(pnode->fInbound, static_cast<const CService&>(pnode->addr));
}
}
}
for (const std::string& strAddNode : lAddresses) {
CService service(LookupNumeric(strAddNode.c_str(), Params().GetDefaultPort()));
AddedNodeInfo addedNode{strAddNode, CService(), false, false};
if (service.IsValid()) {
// strAddNode is an IP:port
auto it = mapConnected.find(service);
if (it != mapConnected.end()) {
addedNode.resolvedAddress = service;
addedNode.fConnected = true;
addedNode.fInbound = it->second;
}
} else {
// strAddNode is a name
auto it = mapConnectedByName.find(strAddNode);
if (it != mapConnectedByName.end()) {
addedNode.resolvedAddress = it->second.second;
addedNode.fConnected = true;
addedNode.fInbound = it->second.first;
}
}
ret.emplace_back(std::move(addedNode));
}
return ret;
}
void CConnman::ThreadOpenAddedConnections()
{
while (true)
{
CSemaphoreGrant grant(*semAddnode);
std::vector<AddedNodeInfo> vInfo = GetAddedNodeInfo();
bool tried = false;
for (const AddedNodeInfo& info : vInfo) {
if (!info.fConnected) {
if (!grant.TryAcquire()) {
// If we've used up our semaphore and need a new one, let's not wait here since while we are waiting
// the addednodeinfo state might change.
break;
}
tried = true;
CAddress addr(CService(), NODE_NONE);
OpenNetworkConnection(addr, false, &grant, info.strAddedNode.c_str(), false, false, true);
if (!interruptNet.sleep_for(std::chrono::milliseconds(500)))
return;
}
}
// Retry every 60 seconds if a connection was attempted, otherwise two seconds
if (!interruptNet.sleep_for(std::chrono::seconds(tried ? 60 : 2)))
return;
}
}
// if successful, this moves the passed grant to the constructed node
void CConnman::OpenNetworkConnection(const CAddress& addrConnect, bool fCountFailure, CSemaphoreGrant *grantOutbound, const char *pszDest, bool fOneShot, bool fFeeler, bool manual_connection)
{
//
// Initiate outbound network connection
//
if (interruptNet) {
return;
}
if (!fNetworkActive) {
return;
}
if (!pszDest) {
if (IsLocal(addrConnect) ||
FindNode(static_cast<CNetAddr>(addrConnect)) || (m_banman && m_banman->IsBanned(addrConnect)) ||
FindNode(addrConnect.ToStringIPPort()))
return;
} else if (FindNode(std::string(pszDest)))
return;
CNode* pnode = ConnectNode(addrConnect, pszDest, fCountFailure, manual_connection);
if (!pnode)
return;
if (grantOutbound)
grantOutbound->MoveTo(pnode->grantOutbound);
if (fOneShot)
pnode->fOneShot = true;
if (fFeeler)
pnode->fFeeler = true;
if (manual_connection)
pnode->m_manual_connection = true;
m_msgproc->InitializeNode(pnode);
{
LOCK(cs_vNodes);
vNodes.push_back(pnode);
}
}
void CConnman::ThreadMessageHandler()
{
while (!flagInterruptMsgProc)
{
std::vector<CNode*> vNodesCopy;
{
LOCK(cs_vNodes);
vNodesCopy = vNodes;
for (CNode* pnode : vNodesCopy) {
pnode->AddRef();
}
}
bool fMoreWork = false;
for (CNode* pnode : vNodesCopy)
{
if (pnode->fDisconnect)
continue;
// Receive messages
bool fMoreNodeWork = m_msgproc->ProcessMessages(pnode, flagInterruptMsgProc);
fMoreWork |= (fMoreNodeWork && !pnode->fPauseSend);
if (flagInterruptMsgProc)
return;
// Send messages
{
LOCK(pnode->cs_sendProcessing);
m_msgproc->SendMessages(pnode);
}
if (flagInterruptMsgProc)
return;
}
{
LOCK(cs_vNodes);
for (CNode* pnode : vNodesCopy)
pnode->Release();
}
WAIT_LOCK(mutexMsgProc, lock);
if (!fMoreWork) {
condMsgProc.wait_until(lock, std::chrono::steady_clock::now() + std::chrono::milliseconds(100), [this] { return fMsgProcWake; });
}
fMsgProcWake = false;
}
}
bool CConnman::BindListenPort(const CService &addrBind, std::string& strError, bool fWhitelisted)
{
strError = "";
int nOne = 1;
// Create socket for listening for incoming connections
struct sockaddr_storage sockaddr;
socklen_t len = sizeof(sockaddr);
if (!addrBind.GetSockAddr((struct sockaddr*)&sockaddr, &len))
{
strError = strprintf("Error: Bind address family for %s not supported", addrBind.ToString());
LogPrintf("%s\n", strError);
return false;
}
SOCKET hListenSocket = CreateSocket(addrBind);
if (hListenSocket == INVALID_SOCKET)
{
strError = strprintf("Error: Couldn't open socket for incoming connections (socket returned error %s)", NetworkErrorString(WSAGetLastError()));
LogPrintf("%s\n", strError);
return false;
}
// Allow binding if the port is still in TIME_WAIT state after
// the program was closed and restarted.
setsockopt(hListenSocket, SOL_SOCKET, SO_REUSEADDR, (sockopt_arg_type)&nOne, sizeof(int));
// some systems don't have IPV6_V6ONLY but are always v6only; others do have the option
// and enable it by default or not. Try to enable it, if possible.
if (addrBind.IsIPv6()) {
#ifdef IPV6_V6ONLY
setsockopt(hListenSocket, IPPROTO_IPV6, IPV6_V6ONLY, (sockopt_arg_type)&nOne, sizeof(int));
#endif
#ifdef WIN32
int nProtLevel = PROTECTION_LEVEL_UNRESTRICTED;
setsockopt(hListenSocket, IPPROTO_IPV6, IPV6_PROTECTION_LEVEL, (const char*)&nProtLevel, sizeof(int));
#endif
}
if (::bind(hListenSocket, (struct sockaddr*)&sockaddr, len) == SOCKET_ERROR)
{
int nErr = WSAGetLastError();
if (nErr == WSAEADDRINUSE)
strError = strprintf(_("Unable to bind to %s on this computer. %s is probably already running."), addrBind.ToString(), _(PACKAGE_NAME));
else
strError = strprintf(_("Unable to bind to %s on this computer (bind returned error %s)"), addrBind.ToString(), NetworkErrorString(nErr));
LogPrintf("%s\n", strError);
CloseSocket(hListenSocket);
return false;
}
LogPrintf("Bound to %s\n", addrBind.ToString());
// Listen for incoming connections
if (listen(hListenSocket, SOMAXCONN) == SOCKET_ERROR)
{
strError = strprintf(_("Error: Listening for incoming connections failed (listen returned error %s)"), NetworkErrorString(WSAGetLastError()));
LogPrintf("%s\n", strError);
CloseSocket(hListenSocket);
return false;
}
vhListenSocket.push_back(ListenSocket(hListenSocket, fWhitelisted));
if (addrBind.IsRoutable() && fDiscover && !fWhitelisted)
AddLocal(addrBind, LOCAL_BIND);
return true;
}
void Discover()
{
if (!fDiscover)
return;
#ifdef WIN32
// Get local host IP
char pszHostName[256] = "";
if (gethostname(pszHostName, sizeof(pszHostName)) != SOCKET_ERROR)
{
std::vector<CNetAddr> vaddr;
if (LookupHost(pszHostName, vaddr, 0, true))
{
for (const CNetAddr &addr : vaddr)
{
if (AddLocal(addr, LOCAL_IF))
LogPrintf("%s: %s - %s\n", __func__, pszHostName, addr.ToString());
}
}
}
#elif (HAVE_DECL_GETIFADDRS && HAVE_DECL_FREEIFADDRS)
// Get local host ip
struct ifaddrs* myaddrs;
if (getifaddrs(&myaddrs) == 0)
{
for (struct ifaddrs* ifa = myaddrs; ifa != nullptr; ifa = ifa->ifa_next)
{
if (ifa->ifa_addr == nullptr) continue;
if ((ifa->ifa_flags & IFF_UP) == 0) continue;
if (strcmp(ifa->ifa_name, "lo") == 0) continue;
if (strcmp(ifa->ifa_name, "lo0") == 0) continue;
if (ifa->ifa_addr->sa_family == AF_INET)
{
struct sockaddr_in* s4 = (struct sockaddr_in*)(ifa->ifa_addr);
CNetAddr addr(s4->sin_addr);
if (AddLocal(addr, LOCAL_IF))
LogPrintf("%s: IPv4 %s: %s\n", __func__, ifa->ifa_name, addr.ToString());
}
else if (ifa->ifa_addr->sa_family == AF_INET6)
{
struct sockaddr_in6* s6 = (struct sockaddr_in6*)(ifa->ifa_addr);
CNetAddr addr(s6->sin6_addr);
if (AddLocal(addr, LOCAL_IF))
LogPrintf("%s: IPv6 %s: %s\n", __func__, ifa->ifa_name, addr.ToString());
}
}
freeifaddrs(myaddrs);
}
#endif
}
void CConnman::SetNetworkActive(bool active)
{
LogPrint(BCLog::NET, "SetNetworkActive: %s\n", active);
if (fNetworkActive == active) {
return;
}
fNetworkActive = active;
uiInterface.NotifyNetworkActiveChanged(fNetworkActive);
}
CConnman::CConnman(uint64_t nSeed0In, uint64_t nSeed1In) : nSeed0(nSeed0In), nSeed1(nSeed1In)
{
SetTryNewOutboundPeer(false);
Options connOptions;
Init(connOptions);
}
NodeId CConnman::GetNewNodeId()
{
return nLastNodeId.fetch_add(1, std::memory_order_relaxed);
}
bool CConnman::Bind(const CService &addr, unsigned int flags) {
if (!(flags & BF_EXPLICIT) && !IsReachable(addr))
return false;
std::string strError;
if (!BindListenPort(addr, strError, (flags & BF_WHITELIST) != 0)) {
if ((flags & BF_REPORT_ERROR) && clientInterface) {
clientInterface->ThreadSafeMessageBox(strError, "", CClientUIInterface::MSG_ERROR);
}
return false;
}
return true;
}
bool CConnman::InitBinds(const std::vector<CService>& binds, const std::vector<CService>& whiteBinds) {
bool fBound = false;
for (const auto& addrBind : binds) {
fBound |= Bind(addrBind, (BF_EXPLICIT | BF_REPORT_ERROR));
}
for (const auto& addrBind : whiteBinds) {
fBound |= Bind(addrBind, (BF_EXPLICIT | BF_REPORT_ERROR | BF_WHITELIST));
}
if (binds.empty() && whiteBinds.empty()) {
struct in_addr inaddr_any;
inaddr_any.s_addr = INADDR_ANY;
struct in6_addr inaddr6_any = IN6ADDR_ANY_INIT;
fBound |= Bind(CService(inaddr6_any, GetListenPort()), BF_NONE);
fBound |= Bind(CService(inaddr_any, GetListenPort()), !fBound ? BF_REPORT_ERROR : BF_NONE);
}
return fBound;
}
bool CConnman::Start(CScheduler& scheduler, const Options& connOptions)
{
Init(connOptions);
{
LOCK(cs_totalBytesRecv);
nTotalBytesRecv = 0;
}
{
LOCK(cs_totalBytesSent);
nTotalBytesSent = 0;
nMaxOutboundTotalBytesSentInCycle = 0;
nMaxOutboundCycleStartTime = 0;
}
if (fListen && !InitBinds(connOptions.vBinds, connOptions.vWhiteBinds)) {
if (clientInterface) {
clientInterface->ThreadSafeMessageBox(
_("Failed to listen on any port. Use -listen=0 if you want this."),
"", CClientUIInterface::MSG_ERROR);
}
return false;
}
for (const auto& strDest : connOptions.vSeedNodes) {
AddOneShot(strDest);
}
if (clientInterface) {
clientInterface->InitMessage(_("Loading P2P addresses..."));
}
// Load addresses from peers.dat
int64_t nStart = GetTimeMillis();
{
CAddrDB adb;
if (adb.Read(addrman))
LogPrintf("Loaded %i addresses from peers.dat %dms\n", addrman.size(), GetTimeMillis() - nStart);
else {
addrman.Clear(); // Addrman can be in an inconsistent state after failure, reset it
LogPrintf("Invalid or missing peers.dat; recreating\n");
DumpAddresses();
}
}
uiInterface.InitMessage(_("Starting network threads..."));
fAddressesInitialized = true;
if (semOutbound == nullptr) {
// initialize semaphore
semOutbound = MakeUnique<CSemaphore>(std::min((nMaxOutbound + nMaxFeeler), nMaxConnections));
}
if (semAddnode == nullptr) {
// initialize semaphore
semAddnode = MakeUnique<CSemaphore>(nMaxAddnode);
}
//
// Start threads
//
assert(m_msgproc);
InterruptSocks5(false);
interruptNet.reset();
flagInterruptMsgProc = false;
{
LOCK(mutexMsgProc);
fMsgProcWake = false;
}
// Send and receive from sockets, accept connections
threadSocketHandler = std::thread(&TraceThread<std::function<void()> >, "net", std::function<void()>(std::bind(&CConnman::ThreadSocketHandler, this)));
if (!gArgs.GetBoolArg("-dnsseed", true))
LogPrintf("DNS seeding disabled\n");
else
threadDNSAddressSeed = std::thread(&TraceThread<std::function<void()> >, "dnsseed", std::function<void()>(std::bind(&CConnman::ThreadDNSAddressSeed, this)));
// Initiate outbound connections from -addnode
threadOpenAddedConnections = std::thread(&TraceThread<std::function<void()> >, "addcon", std::function<void()>(std::bind(&CConnman::ThreadOpenAddedConnections, this)));
if (connOptions.m_use_addrman_outgoing && !connOptions.m_specified_outgoing.empty()) {
if (clientInterface) {
clientInterface->ThreadSafeMessageBox(
_("Cannot provide specific connections and have addrman find outgoing connections at the same."),
"", CClientUIInterface::MSG_ERROR);
}
return false;
}
if (connOptions.m_use_addrman_outgoing || !connOptions.m_specified_outgoing.empty())
threadOpenConnections = std::thread(&TraceThread<std::function<void()> >, "opencon", std::function<void()>(std::bind(&CConnman::ThreadOpenConnections, this, connOptions.m_specified_outgoing)));
// Process messages
threadMessageHandler = std::thread(&TraceThread<std::function<void()> >, "msghand", std::function<void()>(std::bind(&CConnman::ThreadMessageHandler, this)));
// Dump network addresses
scheduler.scheduleEvery(std::bind(&CConnman::DumpAddresses, this), DUMP_PEERS_INTERVAL * 1000);
return true;
}
class CNetCleanup
{
public:
CNetCleanup() {}
~CNetCleanup()
{
#ifdef WIN32
// Shutdown Windows Sockets
WSACleanup();
#endif
}
}
instance_of_cnetcleanup;
void CConnman::Interrupt()
{
{
std::lock_guard<std::mutex> lock(mutexMsgProc);
flagInterruptMsgProc = true;
}
condMsgProc.notify_all();
interruptNet();
InterruptSocks5(true);
if (semOutbound) {
for (int i=0; i<(nMaxOutbound + nMaxFeeler); i++) {
semOutbound->post();
}
}
if (semAddnode) {
for (int i=0; i<nMaxAddnode; i++) {
semAddnode->post();
}
}
}
void CConnman::Stop()
{
if (threadMessageHandler.joinable())
threadMessageHandler.join();
if (threadOpenConnections.joinable())
threadOpenConnections.join();
if (threadOpenAddedConnections.joinable())
threadOpenAddedConnections.join();
if (threadDNSAddressSeed.joinable())
threadDNSAddressSeed.join();
if (threadSocketHandler.joinable())
threadSocketHandler.join();
if (fAddressesInitialized)
{
DumpAddresses();
fAddressesInitialized = false;
}
// Close sockets
for (CNode* pnode : vNodes)
pnode->CloseSocketDisconnect();
for (ListenSocket& hListenSocket : vhListenSocket)
if (hListenSocket.socket != INVALID_SOCKET)
if (!CloseSocket(hListenSocket.socket))
LogPrintf("CloseSocket(hListenSocket) failed with error %s\n", NetworkErrorString(WSAGetLastError()));
// clean up some globals (to help leak detection)
for (CNode *pnode : vNodes) {
DeleteNode(pnode);
}
for (CNode *pnode : vNodesDisconnected) {
DeleteNode(pnode);
}
vNodes.clear();
vNodesDisconnected.clear();
vhListenSocket.clear();
semOutbound.reset();
semAddnode.reset();
}
void CConnman::DeleteNode(CNode* pnode)
{
assert(pnode);
bool fUpdateConnectionTime = false;
m_msgproc->FinalizeNode(pnode->GetId(), fUpdateConnectionTime);
if(fUpdateConnectionTime) {
addrman.Connected(pnode->addr);
}
delete pnode;
}
CConnman::~CConnman()
{
Interrupt();
Stop();
}
size_t CConnman::GetAddressCount() const
{
return addrman.size();
}
void CConnman::SetServices(const CService &addr, ServiceFlags nServices)
{
addrman.SetServices(addr, nServices);
}
void CConnman::MarkAddressGood(const CAddress& addr)
{
addrman.Good(addr);
}
void CConnman::AddNewAddresses(const std::vector<CAddress>& vAddr, const CAddress& addrFrom, int64_t nTimePenalty)
{
addrman.Add(vAddr, addrFrom, nTimePenalty);
}
std::vector<CAddress> CConnman::GetAddresses()
{
return addrman.GetAddr();
}
bool CConnman::AddNode(const std::string& strNode)
{
LOCK(cs_vAddedNodes);
for (const std::string& it : vAddedNodes) {
if (strNode == it) return false;
}
vAddedNodes.push_back(strNode);
return true;
}
bool CConnman::RemoveAddedNode(const std::string& strNode)
{
LOCK(cs_vAddedNodes);
for(std::vector<std::string>::iterator it = vAddedNodes.begin(); it != vAddedNodes.end(); ++it) {
if (strNode == *it) {
vAddedNodes.erase(it);
return true;
}
}
return false;
}
size_t CConnman::GetNodeCount(NumConnections flags)
{
LOCK(cs_vNodes);
if (flags == CConnman::CONNECTIONS_ALL) // Shortcut if we want total
return vNodes.size();
int nNum = 0;
for (const auto& pnode : vNodes) {
if (flags & (pnode->fInbound ? CONNECTIONS_IN : CONNECTIONS_OUT)) {
nNum++;
}
}
return nNum;
}
void CConnman::GetNodeStats(std::vector<CNodeStats>& vstats)
{
vstats.clear();
LOCK(cs_vNodes);
vstats.reserve(vNodes.size());
for (CNode* pnode : vNodes) {
vstats.emplace_back();
pnode->copyStats(vstats.back());
}
}
bool CConnman::DisconnectNode(const std::string& strNode)
{
LOCK(cs_vNodes);
if (CNode* pnode = FindNode(strNode)) {
pnode->fDisconnect = true;
return true;
}
return false;
}
bool CConnman::DisconnectNode(const CSubNet& subnet)
{
bool disconnected = false;
LOCK(cs_vNodes);
for (CNode* pnode : vNodes) {
if (subnet.Match(pnode->addr)) {
pnode->fDisconnect = true;
disconnected = true;
}
}
return disconnected;
}
bool CConnman::DisconnectNode(const CNetAddr& addr)
{
return DisconnectNode(CSubNet(addr));
}
bool CConnman::DisconnectNode(NodeId id)
{
LOCK(cs_vNodes);
for(CNode* pnode : vNodes) {
if (id == pnode->GetId()) {
pnode->fDisconnect = true;
return true;
}
}
return false;
}
void CConnman::RecordBytesRecv(uint64_t bytes)
{
LOCK(cs_totalBytesRecv);
nTotalBytesRecv += bytes;
}
void CConnman::RecordBytesSent(uint64_t bytes)
{
LOCK(cs_totalBytesSent);
nTotalBytesSent += bytes;
uint64_t now = GetTime();
if (nMaxOutboundCycleStartTime + nMaxOutboundTimeframe < now)
{
// timeframe expired, reset cycle
nMaxOutboundCycleStartTime = now;
nMaxOutboundTotalBytesSentInCycle = 0;
}
// TODO, exclude whitebind peers
nMaxOutboundTotalBytesSentInCycle += bytes;
}
void CConnman::SetMaxOutboundTarget(uint64_t limit)
{
LOCK(cs_totalBytesSent);
nMaxOutboundLimit = limit;
}
uint64_t CConnman::GetMaxOutboundTarget()
{
LOCK(cs_totalBytesSent);
return nMaxOutboundLimit;
}
uint64_t CConnman::GetMaxOutboundTimeframe()
{
LOCK(cs_totalBytesSent);
return nMaxOutboundTimeframe;
}
uint64_t CConnman::GetMaxOutboundTimeLeftInCycle()
{
LOCK(cs_totalBytesSent);
if (nMaxOutboundLimit == 0)
return 0;
if (nMaxOutboundCycleStartTime == 0)
return nMaxOutboundTimeframe;
uint64_t cycleEndTime = nMaxOutboundCycleStartTime + nMaxOutboundTimeframe;
uint64_t now = GetTime();
return (cycleEndTime < now) ? 0 : cycleEndTime - GetTime();
}
void CConnman::SetMaxOutboundTimeframe(uint64_t timeframe)
{
LOCK(cs_totalBytesSent);
if (nMaxOutboundTimeframe != timeframe)
{
// reset measure-cycle in case of changing
// the timeframe
nMaxOutboundCycleStartTime = GetTime();
}
nMaxOutboundTimeframe = timeframe;
}
bool CConnman::OutboundTargetReached(bool historicalBlockServingLimit)
{
LOCK(cs_totalBytesSent);
if (nMaxOutboundLimit == 0)
return false;
if (historicalBlockServingLimit)
{
// keep a large enough buffer to at least relay each block once
uint64_t timeLeftInCycle = GetMaxOutboundTimeLeftInCycle();
uint64_t buffer = timeLeftInCycle / 600 * MAX_BLOCK_SERIALIZED_SIZE;
if (buffer >= nMaxOutboundLimit || nMaxOutboundTotalBytesSentInCycle >= nMaxOutboundLimit - buffer)
return true;
}
else if (nMaxOutboundTotalBytesSentInCycle >= nMaxOutboundLimit)
return true;
return false;
}
uint64_t CConnman::GetOutboundTargetBytesLeft()
{
LOCK(cs_totalBytesSent);
if (nMaxOutboundLimit == 0)
return 0;
return (nMaxOutboundTotalBytesSentInCycle >= nMaxOutboundLimit) ? 0 : nMaxOutboundLimit - nMaxOutboundTotalBytesSentInCycle;
}
uint64_t CConnman::GetTotalBytesRecv()
{
LOCK(cs_totalBytesRecv);
return nTotalBytesRecv;
}
uint64_t CConnman::GetTotalBytesSent()
{
LOCK(cs_totalBytesSent);
return nTotalBytesSent;
}
ServiceFlags CConnman::GetLocalServices() const
{
return nLocalServices;
}
void CConnman::SetBestHeight(int height)
{
nBestHeight.store(height, std::memory_order_release);
}
int CConnman::GetBestHeight() const
{
return nBestHeight.load(std::memory_order_acquire);
}
unsigned int CConnman::GetReceiveFloodSize() const { return nReceiveFloodSize; }
CNode::CNode(NodeId idIn, ServiceFlags nLocalServicesIn, int nMyStartingHeightIn, SOCKET hSocketIn, const CAddress& addrIn, uint64_t nKeyedNetGroupIn, uint64_t nLocalHostNonceIn, const CAddress& addrBindIn, const std::string& addrNameIn, bool fInboundIn)
: nTimeConnected(GetSystemTimeInSeconds()),
addr(addrIn),
addrBind(addrBindIn),
fInbound(fInboundIn),
nKeyedNetGroup(nKeyedNetGroupIn),
addrKnown(5000, 0.001),
filterInventoryKnown(50000, 0.000001),
id(idIn),
nLocalHostNonce(nLocalHostNonceIn),
nLocalServices(nLocalServicesIn),
nMyStartingHeight(nMyStartingHeightIn)
{
hSocket = hSocketIn;
addrName = addrNameIn == "" ? addr.ToStringIPPort() : addrNameIn;
hashContinue = uint256();
filterInventoryKnown.reset();
pfilter = MakeUnique<CBloomFilter>();
for (const std::string &msg : getAllNetMessageTypes())
mapRecvBytesPerMsgCmd[msg] = 0;
mapRecvBytesPerMsgCmd[NET_MESSAGE_COMMAND_OTHER] = 0;
if (fLogIPs) {
LogPrint(BCLog::NET, "Added connection to %s peer=%d\n", addrName, id);
} else {
LogPrint(BCLog::NET, "Added connection peer=%d\n", id);
}
}
CNode::~CNode()
{
CloseSocket(hSocket);
}
bool CConnman::NodeFullyConnected(const CNode* pnode)
{
return pnode && pnode->fSuccessfullyConnected && !pnode->fDisconnect;
}
void CConnman::PushMessage(CNode* pnode, CSerializedNetMsg&& msg)
{
size_t nMessageSize = msg.data.size();
size_t nTotalSize = nMessageSize + CMessageHeader::HEADER_SIZE;
LogPrint(BCLog::NET, "sending %s (%d bytes) peer=%d\n", SanitizeString(msg.command.c_str()), nMessageSize, pnode->GetId());
std::vector<unsigned char> serializedHeader;
serializedHeader.reserve(CMessageHeader::HEADER_SIZE);
uint256 hash = Hash(msg.data.data(), msg.data.data() + nMessageSize);
CMessageHeader hdr(Params().MessageStart(), msg.command.c_str(), nMessageSize);
memcpy(hdr.pchChecksum, hash.begin(), CMessageHeader::CHECKSUM_SIZE);
CVectorWriter{SER_NETWORK, INIT_PROTO_VERSION, serializedHeader, 0, hdr};
size_t nBytesSent = 0;
{
LOCK(pnode->cs_vSend);
bool optimisticSend(pnode->vSendMsg.empty());
//log total amount of bytes per command
pnode->mapSendBytesPerMsgCmd[msg.command] += nTotalSize;
pnode->nSendSize += nTotalSize;
if (pnode->nSendSize > nSendBufferMaxSize)
pnode->fPauseSend = true;
pnode->vSendMsg.push_back(std::move(serializedHeader));
if (nMessageSize)
pnode->vSendMsg.push_back(std::move(msg.data));
// If write queue empty, attempt "optimistic write"
if (optimisticSend == true)
nBytesSent = SocketSendData(pnode);
}
if (nBytesSent)
RecordBytesSent(nBytesSent);
}
bool CConnman::ForNode(NodeId id, std::function<bool(CNode* pnode)> func)
{
CNode* found = nullptr;
LOCK(cs_vNodes);
for (auto&& pnode : vNodes) {
if(pnode->GetId() == id) {
found = pnode;
break;
}
}
return found != nullptr && NodeFullyConnected(found) && func(found);
}
int64_t CConnman::PoissonNextSendInbound(int64_t now, int average_interval_seconds)
{
if (m_next_send_inv_to_incoming < now) {
// If this function were called from multiple threads simultaneously
// it would possible that both update the next send variable, and return a different result to their caller.
// This is not possible in practice as only the net processing thread invokes this function.
m_next_send_inv_to_incoming = PoissonNextSend(now, average_interval_seconds);
}
return m_next_send_inv_to_incoming;
}
int64_t PoissonNextSend(int64_t now, int average_interval_seconds)
{
return now + (int64_t)(log1p(GetRand(1ULL << 48) * -0.0000000000000035527136788 /* -1/2^48 */) * average_interval_seconds * -1000000.0 + 0.5);
}
CSipHasher CConnman::GetDeterministicRandomizer(uint64_t id) const
{
return CSipHasher(nSeed0, nSeed1).Write(id);
}
uint64_t CConnman::CalculateKeyedNetGroup(const CAddress& ad) const
{
std::vector<unsigned char> vchNetGroup(ad.GetGroup());
return GetDeterministicRandomizer(RANDOMIZER_ID_NETGROUP).Write(vchNetGroup.data(), vchNetGroup.size()).Finalize();
}