Changeset 436 for trunk/pdns/pdns/pdns_recursor.cc

Timestamp:

07/10/05 14:23:15 (8 years ago)

Author:

ahu

Message:

add TCP client timeouts, add way to limit the number of simultaneous TCP connections

Files:

• trunk/pdns/pdns/pdns_recursor.cc (modified) (8 diffs)

trunk/pdns/pdns/pdns_recursor.cc

@@ -79 +79 @@
 static int d_clientsock;
 static vector<int> d_udpserversocks;
-static vector<int> d_tcpserversocks;
-
+
+typedef vector<int> tcpserversocks_t;
+static tcpserversocks_t s_tcpserversocks;
 
 struct PacketID
@@ -352 +353 @@
     Utility::setNonBlocking(fd);
     listen(fd, 128);
-    d_tcpserversocks.push_back(fd);
+    s_tcpserversocks.push_back(fd);
     L<<Logger::Error<<"Listening for TCP queries on "<<inet_ntoa(sin.sin_addr)<<":"<<arg().asNum("local-port")<<endl;
   }
@@ -469 +470 @@
   struct sockaddr_in remote;
   char data[65535];
+  time_t startTime;
 };
 
@@ -497 +499 @@
     arg().set("delegation-only","Which domains we only accept delegations from")="";
     arg().set("query-local-address","Source IP address for sending queries")="0.0.0.0";
+    arg().set("client-tcp-timeout","Timeout in seconds when talking to TCP clients")="2";
+    arg().set("max-tcp-clients","Maximum number of simultaneous TCP clients")="128";
 
     arg().setCmd("help","Provide a helpful message");
@@ -575 +579 @@
     vector<TCPConnection> tcpconnections;
     counter=0;
+    time_t now;
+    unsigned int maxTcpClients=arg().asNum("max-tcp-clients");
     for(;;) {
       while(MT->schedule()); // housekeeping, let threads do their thing
@@ -597 +603 @@
       int fdmax=d_clientsock;
 
-      for(vector<TCPConnection>::const_iterator i=tcpconnections.begin();i!=tcpconnections.end();++i) {
-        FD_SET(i->fd, &readfds);
-        fdmax=max(fdmax,i->fd);
-      }
+      if(!tcpconnections.empty())
+        now=time(0);
+
+      vector<TCPConnection> sweeped;
+      int tcpLimit=arg().asNum("client-tcp-timeout");
+      for(vector<TCPConnection>::iterator i=tcpconnections.begin();i!=tcpconnections.end();++i) {
+        if(now < i->startTime + tcpLimit) {
+          FD_SET(i->fd, &readfds);
+          fdmax=max(fdmax,i->fd);
+          sweeped.push_back(*i);
+        }
+        else {
+          L<<Logger::Error<<"TCP timeout from client "<<inet_ntoa(i->remote.sin_addr)<<endl;
+          close(i->fd);
+        }
+      }
+      sweeped.swap(tcpconnections);
+
       for(vector<int>::const_iterator i=d_udpserversocks.begin(); i!=d_udpserversocks.end(); ++i) {
         FD_SET( *i, &readfds );
         fdmax=max(fdmax,*i);
       }
-      for(vector<int>::const_iterator i=d_tcpserversocks.begin(); i!=d_tcpserversocks.end(); ++i) {
-        FD_SET( *i, &readfds );
-        fdmax=max(fdmax,*i);
-      }
+      if(tcpconnections.size() < maxTcpClients) 
+        for(tcpserversocks_t::const_iterator i=s_tcpserversocks.begin(); i!=s_tcpserversocks.end(); ++i) {
+          FD_SET(*i, &readfds );
+          fdmax=max(fdmax,*i);
+        }
+
       for(map<int,PacketID>::const_iterator i=d_tcpclientreadsocks.begin(); i!=d_tcpclientreadsocks.end(); ++i) {
         // cerr<<"Adding TCP socket "<<i->first<<" to read select set"<<endl;
@@ -672 +694 @@
       }
 
-      for(vector<int>::const_iterator i=d_tcpserversocks.begin(); i!=d_tcpserversocks.end(); ++i) { 
+      for(tcpserversocks_t::const_iterator i=s_tcpserversocks.begin(); i!=s_tcpserversocks.end(); ++i) { 
         if(FD_ISSET(*i ,&readfds)) { // do we have a new TCP connection
           struct sockaddr_in addr;
@@ -684 +706 @@
             tc.state=TCPConnection::BYTE0;
             tc.remote=addr;
+            tc.startTime=time(0);
             tcpconnections.push_back(tc);
           }