Avoid "Unknown command" messages when receiving getaddr on outbound connections.

Github-Pull: #7642
Rebased-From: d84ea1a59ce3704457a162f1fd8a7353047156de
This commit is contained in:
R E Broadley 2015-06-26 22:38:07 +03:00 committed by MarcoFalke
parent a5bc6a1bc4
commit d3ead9bcb6

View File

@ -5247,13 +5247,18 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv,
}
// This asymmetric behavior for inbound and outbound connections was introduced
// to prevent a fingerprinting attack: an attacker can send specific fake addresses
// to users' AddrMan and later request them by sending getaddr messages.
// Making nodes which are behind NAT and can only make outgoing connections ignore
// the getaddr message mitigates the attack.
else if ((strCommand == NetMsgType::GETADDR) && (pfrom->fInbound))
else if (strCommand == NetMsgType::GETADDR)
{
// This asymmetric behavior for inbound and outbound connections was introduced
// to prevent a fingerprinting attack: an attacker can send specific fake addresses
// to users' AddrMan and later request them by sending getaddr messages.
// Making nodes which are behind NAT and can only make outgoing connections ignore
// the getaddr message mitigates the attack.
if (!pfrom->fInbound) {
LogPrint("net", "Ignoring \"getaddr\" from outbound connection. peer=%d\n", pfrom->id);
return true;
}
pfrom->vAddrToSend.clear();
vector<CAddress> vAddr = addrman.GetAddr();
BOOST_FOREACH(const CAddress &addr, vAddr)