Support for name lookups in -connect and -addnode

* A new option -dns is introduced that enables name lookups in
  -connect and -addnode, which is not enabled by default,
  as it may be considered a security issue.
* A Lookup function is added that supports retrieving one or
  more addresses based on a host name
* CAddress constructors (optionally) support name lookups.
* The different places in the source code that did name lookups
  are refactored to use NameLookup or CAddress instead (dns seeding,
  irc server lookup, getexternalip, ...).
* Removed ToStringLog() from CAddress, and switched to ToString(),
  since it was empty.
This commit is contained in:
Pieter Wuille 2011-05-02 15:34:42 +02:00
parent 04a667b076
commit a6a5bb7c20
4 changed files with 148 additions and 114 deletions

View File

@ -158,6 +158,7 @@ bool AppInit2(int argc, char* argv[])
" -min \t\t " + _("Start minimized\n") +
" -datadir=<dir> \t\t " + _("Specify data directory\n") +
" -proxy=<ip:port> \t " + _("Connect through socks4 proxy\n") +
" -dns \t " + _("Allow DNS lookups for addnode and connect\n") +
" -addnode=<ip> \t " + _("Add a node to connect to\n") +
" -connect=<ip> \t\t " + _("Connect only to the specified node\n") +
" -nolisten \t " + _("Don't accept connections from outside\n") +
@ -208,6 +209,7 @@ bool AppInit2(int argc, char* argv[])
}
fDebug = GetBoolArg("-debug");
fAllowDNS = GetBoolArg("-dns");
#ifndef __WXMSW__
fDaemon = GetBoolArg("-daemon");
@ -458,7 +460,7 @@ bool AppInit2(int argc, char* argv[])
{
foreach(string strAddr, mapMultiArgs["-addnode"])
{
CAddress addr(strAddr, NODE_NETWORK);
CAddress addr(strAddr, fAllowDNS);
addr.nTime = 0; // so it won't relay unless successfully connected
if (addr.IsValid())
AddAddress(addr);

View File

@ -41,7 +41,7 @@ bool DecodeAddress(string str, CAddress& addr)
return false;
memcpy(&tmp, &vch[0], sizeof(tmp));
addr = CAddress(tmp.ip, tmp.port, NODE_NETWORK);
addr = CAddress(tmp.ip, ntohs(tmp.port), NODE_NETWORK);
return true;
}
@ -215,25 +215,15 @@ bool GetIPFromIRC(SOCKET hSocket, string strMyName, unsigned int& ipRet)
return false;
string strHost = str.substr(str.rfind("@")+1);
unsigned int a=0, b=0, c=0, d=0;
if (sscanf(strHost.c_str(), "%u.%u.%u.%u", &a, &b, &c, &d) == 4 &&
inet_addr(strHost.c_str()) != INADDR_NONE)
{
printf("GetIPFromIRC() userhost is IP %s\n", strHost.c_str());
ipRet = CAddress(strHost).ip;
}
else
{
// Hybrid IRC used by lfnet always returns IP when you userhost yourself,
// but in case another IRC is ever used this should work.
printf("GetIPFromIRC() got userhost %s\n", strHost.c_str());
if (fUseProxy)
return false;
struct hostent* phostent = gethostbyname(strHost.c_str());
if (!phostent || !phostent->h_addr_list || !phostent->h_addr_list[0])
return false;
ipRet = *(u_long*)phostent->h_addr_list[0];
}
// Hybrid IRC used by lfnet always returns IP when you userhost yourself,
// but in case another IRC is ever used this should work.
printf("GetIPFromIRC() got userhost %s\n", strHost.c_str());
if (fUseProxy)
return false;
CAddress addr(strHost, 0, true);
if (!addr.IsValid())
return false;
ipRet = addr.ip;
return true;
}
@ -276,9 +266,9 @@ void ThreadIRCSeed2(void* parg)
if (!fTOR)
{
//struct hostent* phostent = gethostbyname("chat.freenode.net");
struct hostent* phostent = gethostbyname("irc.lfnet.org");
if (phostent && phostent->h_addr_list && phostent->h_addr_list[0])
addrConnect = CAddress(*(u_long*)phostent->h_addr_list[0], htons(6667));
CAddress addrIRC("irc.lfnet.org:6667", 0, true);
if (addrIRC.IsValid())
addrConnect = addrIRC;
}
SOCKET hSocket;
@ -390,7 +380,7 @@ void ThreadIRCSeed2(void* parg)
{
addr.nTime = GetAdjustedTime();
if (AddAddress(addr, 51 * 60))
printf("IRC got new address\n");
printf("IRC got new address: %s\n", addr.ToString().c_str());
nGotIRCAddresses++;
}
else

View File

@ -29,8 +29,9 @@ bool OpenNetworkConnection(const CAddress& addrConnect);
// Global state variables
//
bool fClient = false;
bool fAllowDNS = false;
uint64 nLocalServices = (fClient ? 0 : NODE_NETWORK);
CAddress addrLocalHost(0, 0, nLocalServices);
CAddress addrLocalHost("0.0.0.0", 0, false, nLocalServices);
CNode* pnodeLocalHost = NULL;
uint64 nLocalHostNonce = 0;
array<int, 10> vnThreadsRunning;
@ -47,7 +48,7 @@ map<CInv, int64> mapAlreadyAskedFor;
// Settings
int fUseProxy = false;
CAddress addrProxy("127.0.0.1:9050");
CAddress addrProxy("127.0.0.1",9050);
@ -92,7 +93,7 @@ bool ConnectSocket(const CAddress& addrConnect, SOCKET& hSocketRet)
if (fProxy)
{
printf("proxy connecting %s\n", addrConnect.ToStringLog().c_str());
printf("proxy connecting %s\n", addrConnect.ToString().c_str());
char pszSocks4IP[] = "\4\1\0\0\0\0\0\0user";
memcpy(pszSocks4IP + 2, &addrConnect.port, 2);
memcpy(pszSocks4IP + 4, &addrConnect.ip, 4);
@ -118,14 +119,81 @@ bool ConnectSocket(const CAddress& addrConnect, SOCKET& hSocketRet)
printf("ERROR: Proxy returned error %d\n", pchRet[1]);
return false;
}
printf("proxy connected %s\n", addrConnect.ToStringLog().c_str());
printf("proxy connected %s\n", addrConnect.ToString().c_str());
}
hSocketRet = hSocket;
return true;
}
// portDefault is in host order
bool Lookup(const char *pszName, vector<CAddress>& vaddr, int nServices, int nMaxSolutions, bool fAllowLookup, int portDefault, bool fAllowPort)
{
vaddr.clear();
int port = portDefault;
char psz[256];
char *pszHost = psz;
strlcpy(psz, pszName, sizeof(psz));
if (fAllowPort)
{
char* pszColon = strrchr(psz+1,':');
char *pszPortEnd = NULL;
int portParsed = pszColon ? strtoul(pszColon+1, &pszPortEnd, 10) : 0;
if (pszColon && pszPortEnd && pszPortEnd[0] == 0)
{
if (psz[0] == '[' && pszColon[-1] == ']')
{
// Future: enable IPv6 colon-notation inside []
pszHost = psz+1;
pszColon[-1] = 0;
}
else
pszColon[0] = 0;
port = portParsed;
if (port < 0 || port > USHRT_MAX)
port = USHRT_MAX;
}
}
struct in_addr addrIP;
if (inet_aton(pszHost, &addrIP))
{
// valid IP address passed
vaddr.push_back(CAddress(addrIP.s_addr, port, nServices));
return true;
}
if (!fAllowLookup)
return false;
struct hostent* phostent = gethostbyname(pszHost);
if (!phostent)
return false;
if (phostent->h_addrtype != AF_INET)
return false;
char** ppAddr = phostent->h_addr_list;
while (*ppAddr != NULL && vaddr.size() != nMaxSolutions)
{
CAddress addr(((struct in_addr*)ppAddr[0])->s_addr, port, nServices);
if (addr.IsValid())
vaddr.push_back(addr);
ppAddr++;
}
return (vaddr.size() > 0);
}
// portDefault is in host order
bool Lookup(const char *pszName, CAddress& addr, int nServices, bool fAllowLookup, int portDefault, bool fAllowPort)
{
vector<CAddress> vaddr;
bool fRet = Lookup(pszName, vaddr, nServices, 1, fAllowLookup, portDefault, fAllowPort);
if (fRet)
addr = vaddr[0];
return fRet;
}
bool GetMyExternalIP2(const CAddress& addrConnect, const char* pszGet, const char* pszKeyword, unsigned int& ipRet)
{
@ -161,7 +229,7 @@ bool GetMyExternalIP2(const CAddress& addrConnect, const char* pszGet, const cha
strLine = strLine.substr(strspn(strLine.c_str(), " \t\n\r"));
while (strLine.size() > 0 && isspace(strLine[strLine.size()-1]))
strLine.resize(strLine.size()-1);
CAddress addr(strLine.c_str());
CAddress addr(strLine,0,true);
printf("GetMyExternalIP() received [%s] %s\n", strLine.c_str(), addr.ToString().c_str());
if (addr.ip == 0 || addr.ip == INADDR_NONE || !addr.IsRoutable())
return false;
@ -192,13 +260,13 @@ bool GetMyExternalIP(unsigned int& ipRet)
// <?php echo $_SERVER["REMOTE_ADDR"]; ?>
if (nHost == 1)
{
addrConnect = CAddress("91.198.22.70:80"); // checkip.dyndns.org
addrConnect = CAddress("91.198.22.70",80); // checkip.dyndns.org
if (nLookup == 1)
{
struct hostent* phostent = gethostbyname("checkip.dyndns.org");
if (phostent && phostent->h_addr_list && phostent->h_addr_list[0])
addrConnect = CAddress(*(u_long*)phostent->h_addr_list[0], htons(80));
CAddress addrIP("checkip.dyndns.org", 80, true);
if (addrIP.IsValid())
addrConnect = addrIP;
}
pszGet = "GET / HTTP/1.1\r\n"
@ -211,13 +279,13 @@ bool GetMyExternalIP(unsigned int& ipRet)
}
else if (nHost == 2)
{
addrConnect = CAddress("74.208.43.192:80"); // www.showmyip.com
addrConnect = CAddress("74.208.43.192", 80); // www.showmyip.com
if (nLookup == 1)
{
struct hostent* phostent = gethostbyname("www.showmyip.com");
if (phostent && phostent->h_addr_list && phostent->h_addr_list[0])
addrConnect = CAddress(*(u_long*)phostent->h_addr_list[0], htons(80));
CAddress addrIP("www.showmyip.com", 80, true);
if (addrIP.IsValid())
addrConnect = addrIP;
}
pszGet = "GET /simple/ HTTP/1.1\r\n"
@ -283,7 +351,7 @@ bool AddAddress(CAddress addr, int64 nTimePenalty)
if (it == mapAddresses.end())
{
// New address
printf("AddAddress(%s)\n", addr.ToStringLog().c_str());
printf("AddAddress(%s)\n", addr.ToString().c_str());
mapAddresses.insert(make_pair(addr.GetKey(), addr));
CAddrDB().WriteAddress(addr);
return true;
@ -479,7 +547,7 @@ CNode* ConnectNode(CAddress addrConnect, int64 nTimeout)
/// debug print
printf("trying connection %s lastseen=%.1fhrs lasttry=%.1fhrs\n",
addrConnect.ToStringLog().c_str(),
addrConnect.ToString().c_str(),
(double)(addrConnect.nTime - GetAdjustedTime())/3600.0,
(double)(addrConnect.nLastTry - GetAdjustedTime())/3600.0);
@ -491,7 +559,7 @@ CNode* ConnectNode(CAddress addrConnect, int64 nTimeout)
if (ConnectSocket(addrConnect, hSocket))
{
/// debug print
printf("connected %s\n", addrConnect.ToStringLog().c_str());
printf("connected %s\n", addrConnect.ToString().c_str());
// Set to nonblocking
#ifdef __WXMSW__
@ -528,7 +596,7 @@ void CNode::CloseSocketDisconnect()
{
if (fDebug)
printf("%s ", DateTimeStrFormat("%x %H:%M:%S", GetTime()).c_str());
printf("disconnecting node %s\n", addr.ToStringLog().c_str());
printf("disconnecting node %s\n", addr.ToString().c_str());
closesocket(hSocket);
hSocket = INVALID_SOCKET;
}
@ -715,7 +783,7 @@ void ThreadSocketHandler2(void* parg)
}
else
{
printf("accepted connection %s\n", addr.ToStringLog().c_str());
printf("accepted connection %s\n", addr.ToString().c_str());
CNode* pnode = new CNode(hSocket, addr, true);
pnode->AddRef();
CRITICAL_BLOCK(cs_vNodes)
@ -892,7 +960,7 @@ void ThreadMapPort2(void* parg)
printf("ThreadMapPort started\n");
char port[6];
sprintf(port, "%d", ntohs(GetDefaultPort()));
sprintf(port, "%d", GetDefaultPort());
const char * rootdescurl = 0;
const char * multicastif = 0;
@ -984,17 +1052,17 @@ void DNSAddressSeed()
printf("Loading addresses from DNS seeds (could take a while)\n");
for (int seed_idx = 0; seed_idx < ARRAYLEN(strDNSSeed); seed_idx++) {
struct hostent* phostent = gethostbyname(strDNSSeed[seed_idx]);
if (!phostent)
continue;
for (int host = 0; phostent->h_addr_list[host] != NULL; host++) {
CAddress addr(*(unsigned int*)phostent->h_addr_list[host],
GetDefaultPort(), NODE_NETWORK);
addr.nTime = 0;
if (addr.IsValid() && addr.GetByte(3) != 127) {
AddAddress(addr);
found++;
vector<CAddress> vaddr;
if (Lookup(strDNSSeed[seed_idx], vaddr, NODE_NETWORK, true))
{
foreach (CAddress& addr, vaddr)
{
if (addr.GetByte(3) != 127)
{
addr.nTime = 0;
AddAddress(addr);
found++;
}
}
}
}
@ -1080,7 +1148,7 @@ void ThreadOpenConnections2(void* parg)
{
foreach(string strAddr, mapMultiArgs["-connect"])
{
CAddress addr(strAddr, NODE_NETWORK);
CAddress addr(strAddr, fAllowDNS);
if (addr.IsValid())
OpenNetworkConnection(addr);
for (int i = 0; i < 10 && i < nLoop; i++)
@ -1098,7 +1166,7 @@ void ThreadOpenConnections2(void* parg)
{
foreach(string strAddr, mapMultiArgs["-addnode"])
{
CAddress addr(strAddr, NODE_NETWORK);
CAddress addr(strAddr, fAllowDNS);
if (addr.IsValid())
{
OpenNetworkConnection(addr);
@ -1209,7 +1277,7 @@ void ThreadOpenConnections2(void* parg)
// Randomize the order in a deterministic way, putting the standard port first
int64 nRandomizer = (uint64)(nStart * 4951 + addr.nLastTry * 9567851 + addr.ip * 7789) % (2 * 60 * 60);
if (addr.port != GetDefaultPort())
if (addr.port != htons(GetDefaultPort()))
nRandomizer += 2 * 60 * 60;
// Last seen Base retry frequency
@ -1369,7 +1437,7 @@ bool BindListenPort(string& strError)
{
strError = "";
int nOne = 1;
addrLocalHost.port = GetDefaultPort();
addrLocalHost.port = htons(GetDefaultPort());
#ifdef __WXMSW__
// Initialize Windows Sockets
@ -1421,7 +1489,7 @@ bool BindListenPort(string& strError)
memset(&sockaddr, 0, sizeof(sockaddr));
sockaddr.sin_family = AF_INET;
sockaddr.sin_addr.s_addr = INADDR_ANY; // bind to all IPs on this computer
sockaddr.sin_port = GetDefaultPort();
sockaddr.sin_port = htons(GetDefaultPort());
if (::bind(hListenSocket, (struct sockaddr*)&sockaddr, sizeof(sockaddr)) == SOCKET_ERROR)
{
int nErr = WSAGetLastError();
@ -1448,29 +1516,21 @@ bool BindListenPort(string& strError)
void StartNode(void* parg)
{
if (pnodeLocalHost == NULL)
pnodeLocalHost = new CNode(INVALID_SOCKET, CAddress("127.0.0.1", nLocalServices));
pnodeLocalHost = new CNode(INVALID_SOCKET, CAddress("127.0.0.1", 0, false, nLocalServices));
#ifdef __WXMSW__
// Get local host ip
char pszHostName[1000] = "";
if (gethostname(pszHostName, sizeof(pszHostName)) != SOCKET_ERROR)
{
struct hostent* phostent = gethostbyname(pszHostName);
if (phostent)
{
// Take the first IP that isn't loopback 127.x.x.x
for (int i = 0; phostent->h_addr_list[i] != NULL; i++)
printf("host ip %d: %s\n", i, CAddress(*(unsigned int*)phostent->h_addr_list[i]).ToStringIP().c_str());
for (int i = 0; phostent->h_addr_list[i] != NULL; i++)
{
CAddress addr(*(unsigned int*)phostent->h_addr_list[i], GetDefaultPort(), nLocalServices);
if (addr.IsValid() && addr.GetByte(3) != 127)
vector<CAddress> vaddr;
if (NameLookup(pszHostName, vaddr, nLocalServices))
foreach (const CAddress &addr, vaddr)
if (addr.GetByte(3) != 127)
{
addrLocalHost = addr;
break;
}
}
}
}
#else
// Get local host ip
@ -1491,7 +1551,7 @@ void StartNode(void* parg)
printf("ipv4 %s: %s\n", ifa->ifa_name, pszIP);
// Take the first IP that isn't loopback 127.x.x.x
CAddress addr(*(unsigned int*)&s4->sin_addr, GetDefaultPort(), nLocalServices);
CAddress addr(*(unsigned int*)&s4->sin_addr, 0, nLocalServices);
if (addr.IsValid() && addr.GetByte(3) != 127)
{
addrLocalHost = addr;

View File

@ -12,7 +12,7 @@ extern int nBestHeight;
inline unsigned short GetDefaultPort() { return fTestNet ? htons(18333) : htons(8333); }
inline unsigned short GetDefaultPort() { return fTestNet ? 18333 : 8333; }
static const unsigned int PUBLISH_HOPS = 5;
enum
{
@ -23,6 +23,8 @@ enum
bool ConnectSocket(const CAddress& addrConnect, SOCKET& hSocketRet);
bool Lookup(const char *pszName, vector<CAddress>& vaddr, int nServices, int nMaxSolutions, bool fAllowLookup = false, int portDefault = 0, bool fAllowPort = false);
bool Lookup(const char *pszName, CAddress& addr, int nServices, bool fAllowLookup = false, int portDefault = 0, bool fAllowPort = false);
bool GetMyExternalIP(unsigned int& ipRet);
bool AddAddress(CAddress addr, int64 nTimePenalty=0);
void AddressCurrentlyConnected(const CAddress& addr);
@ -156,7 +158,7 @@ public:
{
Init();
ip = ipIn;
port = (portIn == 0 ? GetDefaultPort() : portIn);
port = htons(portIn == 0 ? GetDefaultPort() : portIn);
nServices = nServicesIn;
}
@ -168,18 +170,28 @@ public:
nServices = nServicesIn;
}
explicit CAddress(const char* pszIn, uint64 nServicesIn=NODE_NETWORK)
explicit CAddress(const char* pszIn, int portIn, bool fNameLookup = false, uint64 nServicesIn=NODE_NETWORK)
{
Init();
SetAddress(pszIn);
nServices = nServicesIn;
Lookup(pszIn, *this, nServicesIn, fNameLookup, portIn);
}
explicit CAddress(string strIn, uint64 nServicesIn=NODE_NETWORK)
explicit CAddress(const char* pszIn, bool fNameLookup = false, uint64 nServicesIn=NODE_NETWORK)
{
Init();
SetAddress(strIn.c_str());
nServices = nServicesIn;
Lookup(pszIn, *this, nServicesIn, fNameLookup, 0, true);
}
explicit CAddress(string strIn, int portIn, bool fNameLookup = false, uint64 nServicesIn=NODE_NETWORK)
{
Init();
Lookup(strIn.c_str(), *this, nServicesIn, fNameLookup, portIn);
}
explicit CAddress(string strIn, bool fNameLookup = false, uint64 nServicesIn=NODE_NETWORK)
{
Init();
Lookup(strIn.c_str(), *this, nServicesIn, fNameLookup, 0, true);
}
void Init()
@ -187,37 +199,11 @@ public:
nServices = NODE_NETWORK;
memcpy(pchReserved, pchIPv4, sizeof(pchReserved));
ip = INADDR_NONE;
port = GetDefaultPort();
port = htons(GetDefaultPort());
nTime = 100000000;
nLastTry = 0;
}
bool SetAddress(const char* pszIn)
{
ip = INADDR_NONE;
port = GetDefaultPort();
char psz[100];
strlcpy(psz, pszIn, sizeof(psz));
unsigned int a=0, b=0, c=0, d=0, e=0;
if (sscanf(psz, "%u.%u.%u.%u:%u", &a, &b, &c, &d, &e) < 4)
return false;
char* pszPort = strchr(psz, ':');
if (pszPort)
{
*pszPort++ = '\0';
port = htons(atoi(pszPort));
if (atoi(pszPort) < 0 || atoi(pszPort) > USHRT_MAX)
port = htons(USHRT_MAX);
}
ip = inet_addr(psz);
return IsValid();
}
bool SetAddress(string strIn)
{
return SetAddress(strIn.c_str());
}
IMPLEMENT_SERIALIZE
(
if (fRead)
@ -330,11 +316,6 @@ public:
return strprintf("%u", ntohs(port));
}
string ToStringLog() const
{
return "";
}
string ToString() const
{
return strprintf("%u.%u.%u.%u:%u", GetByte(3), GetByte(2), GetByte(1), GetByte(0), ntohs(port));
@ -460,6 +441,7 @@ public:
extern bool fClient;
extern bool fAllowDNS;
extern uint64 nLocalServices;
extern CAddress addrLocalHost;
extern CNode* pnodeLocalHost;