From 9bab521df895c149579b9e64931405c56b008afb Mon Sep 17 00:00:00 2001
From: Pieter Wuille <pieter.wuille@gmail.com>
Date: Thu, 19 Apr 2012 17:38:03 +0200
Subject: [PATCH] Support connecting by hostnames passed to proxy (-proxydns)

---
 src/init.cpp    |  21 +++-----
 src/net.cpp     | 124 ++++++++++++++++++++++++++++++------------------
 src/net.h       |   7 +--
 src/netbase.cpp |  58 +++++++++++++++++++---
 src/netbase.h   |   4 ++
 5 files changed, 145 insertions(+), 69 deletions(-)

diff --git a/src/init.cpp b/src/init.cpp
index aa1399f81..35da20336 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -181,6 +181,7 @@ bool AppInit2(int argc, char* argv[])
             "  -proxy=<ip:port> \t  "   + _("Connect through socks proxy") + "\n" +
             "  -socks=<n>       \t  "   + _("Select the version of socks proxy to use (4 or 5, 5 is default)") + "\n" +
             "  -dns             \t  "   + _("Allow DNS lookups for addnode and connect") + "\n" +
+            "  -proxydns        \t  "   + _("Pass DNS requests to (SOCKS5) proxy") + "\n" +
             "  -port=<port>     \t\t  " + _("Listen for connections on <port> (default: 8333 or testnet: 18333)") + "\n" +
             "  -maxconnections=<n>\t  " + _("Maintain at most <n> connections to peers (default: 125)") + "\n" +
             "  -addnode=<ip>    \t  "   + _("Add a node to connect to and attempt to keep the connection open") + "\n" +
@@ -524,13 +525,16 @@ bool AppInit2(int argc, char* argv[])
         // Note: the GetBoolArg() calls for all of these must happen later.
         SoftSetBoolArg("-listen", false);
         SoftSetBoolArg("-irc", false);
-        SoftSetBoolArg("-dnsseed", false);
+        SoftSetBoolArg("-proxydns", true);
         SoftSetBoolArg("-upnp", false);
-        SoftSetBoolArg("-dns", false);
     }
 
-    fAllowDNS = GetBoolArg("-dns");
+    fNameLookup = GetBoolArg("-dns");
+    fProxyNameLookup = GetBoolArg("-proxydns");
+    if (fProxyNameLookup)
+        fNameLookup = true;
     fNoListen = !GetBoolArg("-listen", true);
+    nSocksVersion = GetArg("-socks", 5);
 
     // Continue to put "/P2SH/" in the coinbase to monitor
     // BIP16 support.
@@ -548,17 +552,6 @@ bool AppInit2(int argc, char* argv[])
         }
     }
 
-    if (mapArgs.count("-addnode"))
-    {
-        BOOST_FOREACH(string strAddr, mapMultiArgs["-addnode"])
-        {
-            CAddress addr(CService(strAddr, GetDefaultPort(), fAllowDNS));
-            addr.nTime = 0; // so it won't relay unless successfully connected
-            if (addr.IsValid())
-                addrman.Add(addr, CNetAddr("127.0.0.1"));
-        }
-    }
-
     if (mapArgs.count("-paytxfee"))
     {
         if (!ParseMoney(mapArgs["-paytxfee"], nTransactionFee))
diff --git a/src/net.cpp b/src/net.cpp
index 92b4a3173..ca137b70f 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -35,7 +35,7 @@ void ThreadOpenAddedConnections2(void* parg);
 void ThreadMapPort2(void* parg);
 #endif
 void ThreadDNSAddressSeed2(void* parg);
-bool OpenNetworkConnection(const CAddress& addrConnect);
+bool OpenNetworkConnection(const CAddress& addrConnect, const char *strDest = NULL);
 
 
 
@@ -43,7 +43,6 @@ bool OpenNetworkConnection(const CAddress& addrConnect);
 // Global state variables
 //
 bool fClient = false;
-bool fAllowDNS = false;
 static bool fUseUPnP = false;
 uint64 nLocalServices = (fClient ? 0 : NODE_NETWORK);
 CAddress addrLocalHost(CService("0.0.0.0", 0), nLocalServices);
@@ -307,6 +306,15 @@ CNode* FindNode(const CNetAddr& ip)
     return NULL;
 }
 
+CNode* FindNode(std::string addrName)
+{
+    LOCK(cs_vNodes);
+    BOOST_FOREACH(CNode* pnode, vNodes)
+        if (pnode->addrName == addrName)
+            return (pnode);
+    return NULL;
+}
+
 CNode* FindNode(const CService& addr)
 {
     {
@@ -318,35 +326,38 @@ CNode* FindNode(const CService& addr)
     return NULL;
 }
 
-CNode* ConnectNode(CAddress addrConnect, int64 nTimeout)
+CNode* ConnectNode(CAddress addrConnect, const char *pszDest, int64 nTimeout)
 {
-    if ((CNetAddr)addrConnect == (CNetAddr)addrLocalHost)
-        return NULL;
+    if (pszDest != NULL) {
+        if ((CNetAddr)addrConnect == (CNetAddr)addrLocalHost)
+            return NULL;
 
-    // Look for an existing connection
-    CNode* pnode = FindNode((CService)addrConnect);
-    if (pnode)
-    {
-        if (nTimeout != 0)
-            pnode->AddRef(nTimeout);
-        else
-            pnode->AddRef();
-        return pnode;
+        // Look for an existing connection
+        CNode* pnode = FindNode((CService)addrConnect);
+        if (pnode)
+        {
+            if (nTimeout != 0)
+                pnode->AddRef(nTimeout);
+            else
+                pnode->AddRef();
+            return pnode;
+        }
     }
 
+
     /// debug print
     printf("trying connection %s lastseen=%.1fhrs\n",
-        addrConnect.ToString().c_str(),
-        (double)(addrConnect.nTime - GetAdjustedTime())/3600.0);
-
-    addrman.Attempt(addrConnect);
+        pszDest ? pszDest : addrConnect.ToString().c_str(),
+        pszDest ? 0 : (double)(addrConnect.nTime - GetAdjustedTime())/3600.0);
 
     // Connect
     SOCKET hSocket;
-    if (ConnectSocket(addrConnect, hSocket))
+    if (pszDest ? ConnectSocketByName(addrConnect, hSocket, pszDest, GetDefaultPort()) : ConnectSocket(addrConnect, hSocket))
     {
+        addrman.Attempt(addrConnect);
+
         /// debug print
-        printf("connected %s\n", addrConnect.ToString().c_str());
+        printf("connected %s\n", pszDest ? pszDest : addrConnect.ToString().c_str());
 
         // Set to nonblocking
 #ifdef WIN32
@@ -359,11 +370,12 @@ CNode* ConnectNode(CAddress addrConnect, int64 nTimeout)
 #endif
 
         // Add node
-        CNode* pnode = new CNode(hSocket, addrConnect, false);
+        CNode* pnode = new CNode(hSocket, addrConnect, pszDest ? pszDest : "", false);
         if (nTimeout != 0)
             pnode->AddRef(nTimeout);
         else
             pnode->AddRef();
+
         {
             LOCK(cs_vNodes);
             vNodes.push_back(pnode);
@@ -389,7 +401,7 @@ void CNode::CloseSocketDisconnect()
     {
         if (fDebug)
             printf("%s ", DateTimeStrFormat("%x %H:%M:%S", GetTime()).c_str());
-        printf("disconnecting node %s\n", addr.ToString().c_str());
+        printf("disconnecting node %s\n", addrName.c_str());
         closesocket(hSocket);
         hSocket = INVALID_SOCKET;
         vRecv.clear();
@@ -444,7 +456,7 @@ bool CNode::Misbehaving(int howmuch)
 {
     if (addr.IsLocal())
     {
-        printf("Warning: local node %s misbehaving\n", addr.ToString().c_str());
+        printf("Warning: local node %s misbehaving\n", addrName.c_str());
         return false;
     }
 
@@ -458,7 +470,7 @@ bool CNode::Misbehaving(int howmuch)
                 setBanned[addr] = banTime;
         }
         CloseSocketDisconnect();
-        printf("Disconnected %s for misbehavior (score=%d)\n", addr.ToString().c_str(), nMisbehavior);
+        printf("Disconnected %s for misbehavior (score=%d)\n", addrName.c_str(), nMisbehavior);
         return true;
     }
     return false;
@@ -675,7 +687,7 @@ void ThreadSocketHandler2(void* parg)
             else
             {
                 printf("accepted connection %s\n", addr.ToString().c_str());
-                CNode* pnode = new CNode(hSocket, addr, true);
+                CNode* pnode = new CNode(hSocket, addr, "", true);
                 pnode->AddRef();
                 {
                     LOCK(cs_vNodes);
@@ -1025,20 +1037,25 @@ void ThreadDNSAddressSeed2(void* parg)
         printf("Loading addresses from DNS seeds (could take a while)\n");
 
         for (unsigned int seed_idx = 0; seed_idx < ARRAYLEN(strDNSSeed); seed_idx++) {
-            vector<CNetAddr> vaddr;
-            vector<CAddress> vAdd;
-            if (LookupHost(strDNSSeed[seed_idx][1], vaddr))
-            {
-                BOOST_FOREACH(CNetAddr& ip, vaddr)
+            if (fProxyNameLookup) {
+                CAddress addr;
+                OpenNetworkConnection(addr, strDNSSeed[seed_idx][1]);
+            } else {
+                vector<CNetAddr> vaddr;
+                vector<CAddress> vAdd;
+                if (LookupHost(strDNSSeed[seed_idx][1], vaddr))
                 {
-                    int nOneDay = 24*3600;
-                    CAddress addr = CAddress(CService(ip, GetDefaultPort()));
-                    addr.nTime = GetTime() - 3*nOneDay - GetRand(4*nOneDay); // use a random age between 3 and 7 days old
-                    vAdd.push_back(addr);
-                    found++;
+                    BOOST_FOREACH(CNetAddr& ip, vaddr)
+                    {
+                        int nOneDay = 24*3600;
+                        CAddress addr = CAddress(CService(ip, GetDefaultPort()));
+                        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, CNetAddr(strDNSSeed[seed_idx][0], true));
             }
-            addrman.Add(vAdd, CNetAddr(strDNSSeed[seed_idx][0], true));
         }
     }
 
@@ -1199,9 +1216,8 @@ void ThreadOpenConnections2(void* parg)
         {
             BOOST_FOREACH(string strAddr, mapMultiArgs["-connect"])
             {
-                CAddress addr(CService(strAddr, GetDefaultPort(), fAllowDNS));
-                if (addr.IsValid())
-                    OpenNetworkConnection(addr);
+                CAddress addr(CService("0.0.0.0:0"));
+                OpenNetworkConnection(addr, strAddr.c_str());
                 for (int i = 0; i < 10 && i < nLoop; i++)
                 {
                     Sleep(500);
@@ -1325,11 +1341,25 @@ void ThreadOpenAddedConnections2(void* parg)
     if (mapArgs.count("-addnode") == 0)
         return;
 
+    if (fProxyNameLookup) {
+        while(!fShutdown) {
+            BOOST_FOREACH(string& strAddNode, mapMultiArgs["-addnode"]) {
+                CAddress addr;
+                OpenNetworkConnection(addr, strAddNode.c_str());
+                Sleep(500);
+            }
+            vnThreadsRunning[THREAD_ADDEDCONNECTIONS]--;
+            Sleep(120000); // Retry every 2 minutes
+            vnThreadsRunning[THREAD_ADDEDCONNECTIONS]++;
+        }
+        return;
+    }
+
     vector<vector<CService> > vservAddressesToAdd(0);
     BOOST_FOREACH(string& strAddNode, mapMultiArgs["-addnode"])
     {
         vector<CService> vservNode(0);
-        if(Lookup(strAddNode.c_str(), vservNode, GetDefaultPort(), fAllowDNS, 0))
+        if(Lookup(strAddNode.c_str(), vservNode, GetDefaultPort(), fNameLookup, 0))
         {
             vservAddressesToAdd.push_back(vservNode);
             {
@@ -1343,7 +1373,7 @@ void ThreadOpenAddedConnections2(void* parg)
     {
         vector<vector<CService> > vservConnectAddresses = vservAddressesToAdd;
         // Attempt to connect to each IP for each addnode entry until at least one is successful per addnode entry
-        // (keeping in mind that addnode entries can have many IPs if fAllowDNS)
+        // (keeping in mind that addnode entries can have many IPs if fNameLookup)
         {
             LOCK(cs_vNodes);
             BOOST_FOREACH(CNode* pnode, vNodes)
@@ -1373,19 +1403,23 @@ void ThreadOpenAddedConnections2(void* parg)
     }
 }
 
-bool OpenNetworkConnection(const CAddress& addrConnect)
+bool OpenNetworkConnection(const CAddress& addrConnect, const char *strDest)
 {
     //
     // Initiate outbound network connection
     //
     if (fShutdown)
         return false;
-    if ((CNetAddr)addrConnect == (CNetAddr)addrLocalHost || !addrConnect.IsIPv4() ||
-        FindNode((CNetAddr)addrConnect) || CNode::IsBanned(addrConnect))
+    if (!strDest)
+        if ((CNetAddr)addrConnect == (CNetAddr)addrLocalHost || !addrConnect.IsIPv4() ||
+            FindNode((CNetAddr)addrConnect) || CNode::IsBanned(addrConnect) || 
+            FindNode(addrConnect.ToStringIPPort().c_str()))
+            return false;
+    if (strDest && FindNode(strDest))
         return false;
 
     vnThreadsRunning[THREAD_OPENCONNECTIONS]--;
-    CNode* pnode = ConnectNode(addrConnect);
+    CNode* pnode = ConnectNode(addrConnect, strDest);
     vnThreadsRunning[THREAD_OPENCONNECTIONS]++;
     if (fShutdown)
         return false;
diff --git a/src/net.h b/src/net.h
index bad49a9f8..0f48c515b 100644
--- a/src/net.h
+++ b/src/net.h
@@ -35,7 +35,7 @@ bool GetMyExternalIP(CNetAddr& ipRet);
 void AddressCurrentlyConnected(const CService& addr);
 CNode* FindNode(const CNetAddr& ip);
 CNode* FindNode(const CService& ip);
-CNode* ConnectNode(CAddress addrConnect, int64 nTimeout=0);
+CNode* ConnectNode(CAddress addrConnect, const char *strDest = NULL, int64 nTimeout=0);
 void MapPort(bool fMapPort);
 bool BindListenPort(std::string& strError=REF(std::string()));
 void StartNode(void* parg);
@@ -83,7 +83,6 @@ enum threadId
 };
 
 extern bool fClient;
-extern bool fAllowDNS;
 extern uint64 nLocalServices;
 extern CAddress addrLocalHost;
 extern uint64 nLocalHostNonce;
@@ -120,6 +119,7 @@ public:
     int nHeaderStart;
     unsigned int nMessageStart;
     CAddress addr;
+    std::string addrName;
     int nVersion;
     std::string strSubVer;
     bool fClient;
@@ -157,7 +157,7 @@ public:
     CCriticalSection cs_inventory;
     std::multimap<int64, CInv> mapAskFor;
 
-    CNode(SOCKET hSocketIn, CAddress addrIn, bool fInboundIn=false) : vSend(SER_NETWORK, MIN_PROTO_VERSION), vRecv(SER_NETWORK, MIN_PROTO_VERSION)
+    CNode(SOCKET hSocketIn, CAddress addrIn, std::string addrNameIn = "", bool fInboundIn=false) : vSend(SER_NETWORK, MIN_PROTO_VERSION), vRecv(SER_NETWORK, MIN_PROTO_VERSION)
     {
         nServices = 0;
         hSocket = hSocketIn;
@@ -168,6 +168,7 @@ public:
         nHeaderStart = -1;
         nMessageStart = -1;
         addr = addrIn;
+        addrName = addrNameIn == "" ? addr.ToStringIPPort() : addrNameIn;
         nVersion = 0;
         strSubVer = "";
         fClient = false; // set by version message
diff --git a/src/netbase.cpp b/src/netbase.cpp
index 60f34bbd3..a9cc0cf4d 100644
--- a/src/netbase.cpp
+++ b/src/netbase.cpp
@@ -15,7 +15,10 @@
 using namespace std;
 
 // Settings
+int nSocksVersion = 5;
 int fUseProxy = false;
+bool fProxyNameLookup = false;
+bool fNameLookup = false;
 CService addrProxy("127.0.0.1",9050);
 int nConnectTimeout = 5000;
 
@@ -310,12 +313,12 @@ bool static ConnectSocketDirectly(const CService &addrConnect, SOCKET& hSocketRe
     setsockopt(hSocket, SOL_SOCKET, SO_NOSIGPIPE, (void*)&set, sizeof(int));
 #endif
 
-    bool fProxy = (fUseProxy && addrDest.IsRoutable());
     struct sockaddr_in sockaddr;
-    if (fProxy)
-        addrProxy.GetSockAddr(&sockaddr);
-    else
-        addrDest.GetSockAddr(&sockaddr);
+    if (!addrConnect.GetSockAddr(&sockaddr))
+    {
+        closesocket(hSocket);
+        return false;
+    }
 
 #ifdef WIN32
     u_long fNonblock = 1;
@@ -329,7 +332,6 @@ bool static ConnectSocketDirectly(const CService &addrConnect, SOCKET& hSocketRe
         return false;
     }
 
-
     if (connect(hSocket, (struct sockaddr*)&sockaddr, sizeof(sockaddr)) == SOCKET_ERROR)
     {
         // WSAEINVAL is here because some legacy version of winsock uses it
@@ -414,7 +416,7 @@ bool ConnectSocket(const CService &addrDest, SOCKET& hSocketRet, int nTimeout)
 
     if (fProxy)
     {
-        switch(GetArg("-socks", 5))
+        switch(nSocksVersion)
         {
             case 4:
                 if (!Socks4(addrDest, hSocket))
@@ -433,6 +435,48 @@ bool ConnectSocket(const CService &addrDest, SOCKET& hSocketRet, int nTimeout)
     return true;
 }
 
+bool ConnectSocketByName(CService &addr, SOCKET& hSocketRet, const char *pszDest, int portDefault, int nTimeout)
+{
+    string strDest(pszDest);
+    int port = portDefault;
+
+    size_t colon = strDest.find_last_of(':');
+    char *endp = NULL;
+    int n = strtol(pszDest + colon + 1, &endp, 10);
+    if (endp && *endp == 0 && n >= 0) {
+        strDest = strDest.substr(0, colon);
+        if (n > 0 && n < 0x10000)
+            port = n;
+    }
+    if (strDest[0] == '[' && strDest[strDest.size()-1] == ']')
+        strDest = strDest.substr(1, strDest.size()-2);
+
+    SOCKET hSocket = INVALID_SOCKET;
+    CService addrResolved(CNetAddr(strDest, fNameLookup && !fProxyNameLookup), port);
+    if (addrResolved.IsValid()) {
+        addr = addrResolved;
+        return ConnectSocket(addr, hSocketRet, nTimeout);
+    }
+    addr = CService("0.0.0.0:0");
+    if (!fNameLookup)
+        return false;
+    if (!ConnectSocketDirectly(addrProxy, hSocket, nTimeout))
+        return false;
+
+    switch(nSocksVersion)
+        {
+            case 4: return false;
+            case 5:
+            default:
+                if (!Socks5(strDest, port, hSocket))
+                    return false;
+                break;
+        }
+
+    hSocketRet = hSocket;
+    return true;
+}
+
 void CNetAddr::Init()
 {
     memset(ip, 0, 16);
diff --git a/src/netbase.h b/src/netbase.h
index 00b6850b2..3d2956906 100644
--- a/src/netbase.h
+++ b/src/netbase.h
@@ -119,9 +119,13 @@ bool Lookup(const char *pszName, CService& addr, int portDefault = 0, bool fAllo
 bool Lookup(const char *pszName, std::vector<CService>& vAddr, int portDefault = 0, bool fAllowLookup = true, unsigned int nMaxSolutions = 0);
 bool LookupNumeric(const char *pszName, CService& addr, int portDefault = 0);
 bool ConnectSocket(const CService &addr, SOCKET& hSocketRet, int nTimeout = nConnectTimeout);
+bool ConnectSocketByName(CService &addr, SOCKET& hSocketRet, const char *pszDest, int portDefault = 0, int nTimeout = nConnectTimeout);
 
 // Settings
+extern int nSocksVersion;
 extern int fUseProxy;
+extern bool fProxyNameLookup;
+extern bool fNameLookup;
 extern CService addrProxy;
 
 #endif