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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>After looking into the code that is used for proxying the dns requests to the recursor server, I was wondering what happens when the responses are larger than 1500 bytes? Wouldn’t this potentially cause issues when large data sets are passed back (DNSSEC data, etc.)?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>void DNSProxy::mainloop(void)<o:p></o:p></p><p class=MsoNormal>{<o:p></o:p></p><p class=MsoNormal> try {<o:p></o:p></p><p class=MsoNormal> char buffer[1500]; <span style='font-family:Wingdings'>ß</span>Buffer to small for large datasets<o:p></o:p></p><p class=MsoNormal> int len;<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal> for(;;) {<o:p></o:p></p><p class=MsoNormal> len=recv(d_sock, buffer, sizeof(buffer),0); // answer from our backend<o:p></o:p></p><p class=MsoNormal> if(len<12) {<o:p></o:p></p><p class=MsoNormal> if(len<0)<o:p></o:p></p><p class=MsoNormal> L<<Logger::Error<<"Error receiving packet from recursor backend: "<<stringerror()<<endl;<o:p></o:p></p><p class=MsoNormal> else if(len==0)<o:p></o:p></p><p class=MsoNormal> L<<Logger::Error<<"Error receiving packet from recursor backend, EOF"<<endl;<o:p></o:p></p><p class=MsoNormal> else<o:p></o:p></p><p class=MsoNormal> L<<Logger::Error<<"Short packet from recursor backend, "<<len<<" bytes"<<endl;<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal> continue;<o:p></o:p></p><p class=MsoNormal> }<o:p></o:p></p><p class=MsoNormal> (*d_resanswers)++;<o:p></o:p></p><p class=MsoNormal> (*d_udpanswers)++;<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Also, digging into the class DNSPacket which is used later on to store the data that has been sent back, there appears to be a limit of 1680 bytes. (line 442 in DNSpacket.cc)<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Steve<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>