Merge pull request #5161

845c86d Do not use third party services for IP detection. (Gregory Maxwell)

4 files changed, 61 insertions, 148 deletions

diff --git a/src/init.cpp b/src/init.cpp
index 22ec80e17b..b290d54158 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -574,6 +574,9 @@ bool AppInit2(boost::thread_group& threadGroup)
         // to protect privacy, do not listen by default if a default proxy server is specified
         if (SoftSetBoolArg("-listen", false))
             LogPrintf("AppInit2 : parameter interaction: -proxy set -> setting -listen=0\n");
+        // to protect privacy, do not discover addresses by default
+        if (SoftSetBoolArg("-discover", false))
+            LogPrintf("AppInit2 : parameter interaction: -proxy set -> setting -discover=0\n");
     }
 
     if (!GetBoolArg("-listen", true)) {
diff --git a/src/main.cpp b/src/main.cpp
index 4aa49531b3..2bff781bfa 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -3478,12 +3478,6 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv,
         else
             pfrom->fRelayTxes = true;
 
-        if (pfrom->fInbound && addrMe.IsRoutable())
-        {
-            pfrom->addrLocal = addrMe;
-            SeenLocal(addrMe);
-        }
-
         // Disconnect if we connected to ourself
         if (nNonce == nLocalHostNonce && nNonce > 1)
         {
@@ -3492,6 +3486,12 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv,
             return true;
         }
 
+        pfrom->addrLocal = addrMe;
+        if (pfrom->fInbound && addrMe.IsRoutable())
+        {
+            SeenLocal(addrMe);
+        }
+
         // Be shy and don't send version until we hear
         if (pfrom->fInbound)
             pfrom->PushVersion();
@@ -3512,7 +3512,12 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv,
             {
                 CAddress addr = GetLocalAddress(&pfrom->addr);
                 if (addr.IsRoutable())
+                {
+                    pfrom->PushAddress(addr);
+                } else if (IsPeerAddrLocalGood(pfrom)) {
+                    addr.SetIP(pfrom->addrLocal);
                     pfrom->PushAddress(addr);
+                }
             }
 
             // Get recent addresses
@@ -4375,24 +4380,18 @@ bool SendMessages(CNode* pto, bool fSendTrickle)
         static int64_t nLastRebroadcast;
         if (!IsInitialBlockDownload() && (GetTime() - nLastRebroadcast > 24 * 60 * 60))
         {
+            LOCK(cs_vNodes);
+            BOOST_FOREACH(CNode* pnode, vNodes)
             {
-                LOCK(cs_vNodes);
-                BOOST_FOREACH(CNode* pnode, vNodes)
-                {
-                    // Periodically clear setAddrKnown to allow refresh broadcasts
-                    if (nLastRebroadcast)
-                        pnode->setAddrKnown.clear();
+                // Periodically clear setAddrKnown to allow refresh broadcasts
+                if (nLastRebroadcast)
+                    pnode->setAddrKnown.clear();
 
-                    // Rebroadcast our address
-                    if (fListen)
-                    {
-                        CAddress addr = GetLocalAddress(&pnode->addr);
-                        if (addr.IsRoutable())
-                            pnode->PushAddress(addr);
-                    }
-                }
+                // Rebroadcast our address
+                AdvertizeLocal(pnode);
             }
-            nLastRebroadcast = GetTime();
+            if (!vNodes.empty())
+                nLastRebroadcast = GetTime();
         }
 
         //
diff --git a/src/net.cpp b/src/net.cpp
index 5ceb82cf8b..a66875a894 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -142,16 +142,19 @@ bool GetLocal(CService& addr, const CNetAddr *paddrPeer)
 }
 
 // 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)
 {
-    CAddress ret(CService("0.0.0.0",0),0);
+    CAddress ret(CService("0.0.0.0",GetListenPort()),0);
     CService addr;
     if (GetLocal(addr, paddrPeer))
     {
         ret = CAddress(addr);
-        ret.nServices = nLocalServices;
-        ret.nTime = GetAdjustedTime();
     }
+    ret.nServices = nLocalServices;
+    ret.nTime = GetAdjustedTime();
     return ret;
 }
 
@@ -205,21 +208,38 @@ bool RecvLine(SOCKET hSocket, string& strLine)
     }
 }
 
-// used when scores of local addresses may have changed
-// pushes better local address to peers
-void static AdvertizeLocal()
+int GetnScore(const CService& addr)
 {
-    LOCK(cs_vNodes);
-    BOOST_FOREACH(CNode* pnode, vNodes)
+    LOCK(cs_mapLocalHost);
+    if (mapLocalHost.count(addr) == LOCAL_NONE)
+        return 0;
+    return mapLocalHost[addr].nScore;
+}
+
+// Is our peer's addrLocal potentially useful as an external IP source?
+bool IsPeerAddrLocalGood(CNode *pnode)
+{
+    return fDiscover && pnode->addr.IsRoutable() && pnode->addrLocal.IsRoutable() &&
+           !IsLimited(pnode->addrLocal.GetNetwork());
+}
+
+// pushes our own address to a peer
+void AdvertizeLocal(CNode *pnode)
+{
+    if (fListen && pnode->fSuccessfullyConnected)
     {
-        if (pnode->fSuccessfullyConnected)
+        CAddress addrLocal = GetLocalAddress(&pnode->addr);
+        // 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.
+        if (IsPeerAddrLocalGood(pnode) && (!addrLocal.IsRoutable() ||
+             GetRand((GetnScore(addrLocal) > LOCAL_MANUAL) ? 8:2) == 0))
         {
-            CAddress addrLocal = GetLocalAddress(&pnode->addr);
-            if (addrLocal.IsRoutable() && (CService)addrLocal != (CService)pnode->addrLocal)
-            {
-                pnode->PushAddress(addrLocal);
-                pnode->addrLocal = addrLocal;
-            }
+            addrLocal.SetIP(pnode->addrLocal);
+        }
+        if (addrLocal.IsRoutable())
+        {
+            pnode->PushAddress(addrLocal);
         }
     }
 }
@@ -257,8 +277,6 @@ bool AddLocal(const CService& addr, int nScore)
         SetReachable(addr.GetNetwork());
     }
 
-    AdvertizeLocal();
-
     return true;
 }
 
@@ -296,12 +314,10 @@ bool SeenLocal(const CService& addr)
             return false;
         mapLocalHost[addr].nScore++;
     }
-
-    AdvertizeLocal();
-
     return true;
 }
 
+
 /** check whether a given address is potentially local */
 bool IsLocal(const CService& addr)
 {
@@ -323,114 +339,12 @@ bool IsReachable(const CNetAddr& addr)
     return IsReachable(net);
 }
 
-bool GetMyExternalIP2(const CService& addrConnect, const char* pszGet, const char* pszKeyword, CNetAddr& ipRet)
-{
-    SOCKET hSocket;
-    if (!ConnectSocket(addrConnect, hSocket))
-        return error("GetMyExternalIP() : connection to %s failed", addrConnect.ToString());
-
-    send(hSocket, pszGet, strlen(pszGet), MSG_NOSIGNAL);
-
-    string strLine;
-    while (RecvLine(hSocket, strLine))
-    {
-        if (strLine.empty()) // HTTP response is separated from headers by blank line
-        {
-            while (true)
-            {
-                if (!RecvLine(hSocket, strLine))
-                {
-                    CloseSocket(hSocket);
-                    return false;
-                }
-                if (pszKeyword == NULL)
-                    break;
-                if (strLine.find(pszKeyword) != string::npos)
-                {
-                    strLine = strLine.substr(strLine.find(pszKeyword) + strlen(pszKeyword));
-                    break;
-                }
-            }
-            CloseSocket(hSocket);
-            if (strLine.find("<") != string::npos)
-                strLine = strLine.substr(0, strLine.find("<"));
-            strLine = strLine.substr(strspn(strLine.c_str(), " \t\n\r"));
-            while (strLine.size() > 0 && isspace(strLine[strLine.size()-1]))
-                strLine.resize(strLine.size()-1);
-            CService addr(strLine,0,true);
-            LogPrintf("GetMyExternalIP() received [%s] %s\n", strLine, addr.ToString());
-            if (!addr.IsValid() || !addr.IsRoutable())
-                return false;
-            ipRet.SetIP(addr);
-            return true;
-        }
-    }
-    CloseSocket(hSocket);
-    return error("GetMyExternalIP() : connection closed");
-}
-
-bool GetMyExternalIP(CNetAddr& ipRet)
-{
-    CService addrConnect;
-    const char* pszGet;
-    const char* pszKeyword;
-
-    for (int nLookup = 0; nLookup <= 1; nLookup++)
-    for (int nHost = 1; nHost <= 1; nHost++)
-    {
-        // We should be phasing out our use of sites like these. If we need
-        // replacements, we should ask for volunteers to put this simple
-        // php file on their web server that prints the client IP:
-        //  <?php echo $_SERVER["REMOTE_ADDR"]; ?>
-        if (nHost == 1)
-        {
-            addrConnect = CService("91.198.22.70", 80); // checkip.dyndns.org
-
-            if (nLookup == 1)
-            {
-                CService addrIP("checkip.dyndns.org", 80, true);
-                if (addrIP.IsValid())
-                    addrConnect = addrIP;
-            }
-
-            pszGet = "GET / HTTP/1.1\r\n"
-                     "Host: checkip.dyndns.org\r\n"
-                     "User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1)\r\n"
-                     "Connection: close\r\n"
-                     "\r\n";
-
-            pszKeyword = "Address:";
-        }
-
-        if (GetMyExternalIP2(addrConnect, pszGet, pszKeyword, ipRet))
-            return true;
-    }
-
-    return false;
-}
-
-void ThreadGetMyExternalIP()
-{
-    CNetAddr addrLocalHost;
-    if (GetMyExternalIP(addrLocalHost))
-    {
-        LogPrintf("GetMyExternalIP() returned %s\n", addrLocalHost.ToStringIP());
-        AddLocal(addrLocalHost, LOCAL_HTTP);
-    }
-}
-
-
-
-
-
 void AddressCurrentlyConnected(const CService& addr)
 {
     addrman.Connected(addr);
 }
 
 
-
-
 uint64_t CNode::nTotalBytesRecv = 0;
 uint64_t CNode::nTotalBytesSent = 0;
 CCriticalSection CNode::cs_totalBytesRecv;
@@ -1687,9 +1601,6 @@ void static Discover(boost::thread_group& threadGroup)
     }
 #endif
 
-    // Don't use external IPv4 discovery, when -onlynet="IPv6"
-    if (!IsLimited(NET_IPV4))
-        threadGroup.create_thread(boost::bind(&TraceThread<void (*)()>, "ext-ip", &ThreadGetMyExternalIP));
 }
 
 void StartNode(boost::thread_group& threadGroup)
diff --git a/src/net.h b/src/net.h
index 340158512d..e48acf5644 100644
--- a/src/net.h
+++ b/src/net.h
@@ -60,7 +60,6 @@ unsigned int SendBufferSize();
 
 void AddOneShot(std::string strDest);
 bool RecvLine(SOCKET hSocket, std::string& strLine);
-bool GetMyExternalIP(CNetAddr& ipRet);
 void AddressCurrentlyConnected(const CService& addr);
 CNode* FindNode(const CNetAddr& ip);
 CNode* FindNode(const std::string& addrName);
@@ -96,12 +95,13 @@ enum
     LOCAL_IF,     // address a local interface listens on
     LOCAL_BIND,   // address explicit bound to
     LOCAL_UPNP,   // address reported by UPnP
-    LOCAL_HTTP,   // address reported by whatismyip.com and similar
     LOCAL_MANUAL, // address explicitly specified (-externalip=)
 
     LOCAL_MAX
 };
 
+bool IsPeerAddrLocalGood(CNode *pnode);
+void AdvertizeLocal(CNode *pnode);
 void SetLimited(enum Network net, bool fLimited = true);
 bool IsLimited(enum Network net);
 bool IsLimited(const CNetAddr& addr);