From: Devdas Bhagat <devdas.bhagat@booking.com>
Date: Fri, 6 Dec 2013 11:18:17 +0000 (+0100)
Subject: Add support for id.server requests following RFC 4892
X-Git-Tag: rec-3.6.0-rc1~284^2~1
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=8ca1a435231ddfcf9ce5ee2dbb92073afb31fd05;p=thirdparty%2Fpdns.git

Add support for id.server requests following RFC 4892
---

diff --git a/pdns/common_startup.cc b/pdns/common_startup.cc
index 1a2227d878..a66a5fb0e7 100644
--- a/pdns/common_startup.cc
+++ b/pdns/common_startup.cc
@@ -122,7 +122,7 @@ void declareArguments()
   ::arg().set("negquery-cache-ttl","Seconds to store negative query results in the QueryCache")="60";
   ::arg().set("query-cache-ttl","Seconds to store query results in the QueryCache")="20";
   ::arg().set("soa-minimum-ttl","Default SOA minimum ttl")="3600";
-  ::arg().set("server-id", "Returned when queried for 'server.id' TXT or NSID, defaults to hostname")="";
+  ::arg().set("server-id", "Returned when queried for 'server.id' TXT or NSID, defaults to hostname  - valid options: anonymous, disabled or custom")="");
   ::arg().set("soa-refresh-default","Default SOA refresh")="10800";
   ::arg().set("soa-retry-default","Default SOA retry")="3600";
   ::arg().set("soa-expire-default","Default SOA expire")="604800";
diff --git a/pdns/dnspacket.cc b/pdns/dnspacket.cc
index 0d2e0008b3..242eab94ca 100644
--- a/pdns/dnspacket.cc
+++ b/pdns/dnspacket.cc
@@ -286,7 +286,10 @@ void DNSPacket::wrapup()
   
   DNSPacketWriter::optvect_t opts;
   if(d_wantsnsid) {
-    opts.push_back(make_pair(3, ::arg()["server-id"]));
+    const static string mode_server_id=::arg()["server-id"];
+    if(mode_server_id != "anonymous" && mode_server_id != "disabled") {
+      opts.push_back(make_pair(3, mode_server_id));
+    }
   }
 
   if(!d_ednsping.empty()) {
diff --git a/pdns/packethandler.cc b/pdns/packethandler.cc
index 1d54bcbf32..471e2e0a41 100644
--- a/pdns/packethandler.cc
+++ b/pdns/packethandler.cc
@@ -261,20 +261,39 @@ int PacketHandler::doVersionRequest(DNSPacket *p, DNSPacket *r, string &target)
 {
   DNSResourceRecord rr;
   
-  if(p->qclass == QClass::CHAOS && p->qtype.getCode()==QType::TXT && target=="version.bind") {// TXT
+  if(p->qclass == QClass::CHAOS && p->qtype.getCode()==QType::TXT && 
+    (target == "version.bind") || (target == "id.server") || (target == "version.pdns") ) {// TXT
     // modes: anonymous, powerdns only, full, spoofed
-    const static string mode=::arg()["version-string"];
-  
-    if(mode.empty() || mode=="full") 
-      rr.content=fullVersionString();
-    else if(mode=="anonymous") {
-      r->setRcode(RCode::ServFail);
-      return 1;
+
+    static string mode;
+    if (target == "id.server") {
+      mode=::arg()["server-id"];
+
+      if (mode == "anonymous") {
+        r->setRcode(RCode::ServFail);
+        return 1;
+      }
+      else if (mode == "disabled") {
+        return 0;
+      }
+      else
+        rr.content=mode;
+    } // We were asked for a version, not RFC 4892 id.server
+    else {
+      mode=::arg()["version-string"];
+    
+      if(mode.empty() || mode=="full") 
+        rr.content=fullVersionString();
+      else if(mode=="anonymous") {
+        r->setRcode(RCode::ServFail);
+        return 1;
+      }
+      else if(mode=="powerdns") {
+        rr.content="Served by PowerDNS - http://www.powerdns.com";
+      }
+      else 
+        rr.content=mode;
     }
-    else if(mode=="powerdns")
-      rr.content="Served by PowerDNS - http://www.powerdns.com";
-    else 
-      rr.content=mode;
 
     rr.ttl=5;
     rr.qname=target;
diff --git a/pdns/pdns.conf-dist b/pdns/pdns.conf-dist
index 4490949d4c..355d3a0580 100644
--- a/pdns/pdns.conf-dist
+++ b/pdns/pdns.conf-dist
@@ -325,7 +325,7 @@
 # send-root-referral=no
 
 #################################
-# server-id	Returned when queried for 'server.id' TXT or NSID, defaults to hostname
+# server-id	Returned when queried for 'server.id' TXT or NSID, defaults to hostname - valid options: anonymous, disabled or custom
 #
 # server-id=