From 2188dcc3e683f7f47275d066fea52aa36ec87fa4 Mon Sep 17 00:00:00 2001
From: Bert Hubert <bert.hubert@netherlabs.nl>
Date: Mon, 4 Feb 2008 22:32:49 +0000
Subject: [PATCH] reprime root hints using EDNS0, thanks to dns-operations AT
 mail.oarc.isc.org

git-svn-id: svn://svn.powerdns.com/pdns/trunk/pdns@1130 d19b8d6e-7fed-0310-83ef-9ca221ded41b
---
 pdns/lwres.cc         | 7 ++++++-
 pdns/lwres.hh         | 2 +-
 pdns/pdns_recursor.cc | 2 +-
 pdns/syncres.cc       | 8 ++++++--
 pdns/syncres.hh       | 9 ++++++++-
 5 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/pdns/lwres.cc b/pdns/lwres.cc
index 40165b0e37..50f8f6a890 100644
--- a/pdns/lwres.cc
+++ b/pdns/lwres.cc
@@ -40,7 +40,7 @@
 
 //! returns -2 for OS limits error, -1 for permanent error that has to do with remote, 0 for timeout, 1 for success
 /** Never throws! */
-int asyncresolve(const ComboAddress& ip, const string& domain, int type, bool doTCP, struct timeval* now, LWResult *lwr)
+int asyncresolve(const ComboAddress& ip, const string& domain, int type, bool doTCP, bool doEDNS0, struct timeval* now, LWResult *lwr)
 {
   int len; 
   int bufsize=1500;
@@ -50,6 +50,11 @@ int asyncresolve(const ComboAddress& ip, const string& domain, int type, bool do
 
   pw.getHeader()->rd=0;
   pw.getHeader()->id=Utility::random();
+
+  if(doEDNS0 && !doTCP) {
+    pw.addOpt(1200, 0, 0); // 1200 bytes answer size
+    pw.commit();
+  }
   lwr->d_rcode=0;
 
   int ret;
diff --git a/pdns/lwres.hh b/pdns/lwres.hh
index d0d3a6546e..611340f1e8 100644
--- a/pdns/lwres.hh
+++ b/pdns/lwres.hh
@@ -63,6 +63,6 @@ public:
   uint32_t d_usec;
 };
 
-int asyncresolve(const ComboAddress& ip, const string& domain, int type, bool doTCP, struct timeval* now, LWResult* res);
+int asyncresolve(const ComboAddress& ip, const string& domain, int type, bool doTCP, bool doEDNS0, struct timeval* now, LWResult* res);
 
 #endif // PDNS_LWRES_HH
diff --git a/pdns/pdns_recursor.cc b/pdns/pdns_recursor.cc
index 16e59f0522..cc76d05cd0 100644
--- a/pdns/pdns_recursor.cc
+++ b/pdns/pdns_recursor.cc
@@ -33,7 +33,6 @@
 #include <stdio.h>
 #include <signal.h>
 #include <stdlib.h>
-#include "htimer.hh"
 
 #include "mtasker.hh"
 #include <utility>
@@ -1127,6 +1126,7 @@ try
   }
   if(now.tv_sec - last_rootupdate > 7200) {
     SyncRes sr(now);
+    sr.setDoEDNS0(true);
     vector<DNSResourceRecord> ret;
 
     sr.setNoCache();
diff --git a/pdns/syncres.cc b/pdns/syncres.cc
index 74a3605d76..bfdd27559a 100644
--- a/pdns/syncres.cc
+++ b/pdns/syncres.cc
@@ -212,7 +212,7 @@ int SyncRes::doResolve(const string &qname, const QType &qtype, vector<DNSResour
 	  LOG<<prefix<<qname<<": forwarding query to hardcoded nameserver '"<<server<<"' for zone '"<<authname<<"'"<<endl;
 	  ComboAddress remoteIP(server, 53);
 
-	  res=asyncresolve(remoteIP, qname, qtype.getCode(), false, &d_now, &lwr);    
+	  res=asyncresolve(remoteIP, qname, qtype.getCode(), false, false, &d_now, &lwr);    
 	  // filter out the good stuff from lwr.result()
 
 	  for(LWResult::res_t::const_iterator i=lwr.d_result.begin();i!=lwr.d_result.end();++i) {
@@ -680,7 +680,7 @@ int SyncRes::doResolveAt(set<string, CIStringCompare> nameservers, string auth,
 	      s_tcpoutqueries++; d_tcpoutqueries++;
 	    }
 	    
-	    resolveret=asyncresolve(*remoteIP, qname, qtype.getCode(), doTCP, &d_now, &lwr);    // <- we go out on the wire!
+	    resolveret=asyncresolve(*remoteIP, qname, qtype.getCode(), doTCP, d_doEDNS0, &d_now, &lwr);    // <- we go out on the wire!
 	    if(resolveret != 1) {
 	      if(resolveret==0) {
 		LOG<<prefix<<qname<<": timeout resolving "<< (doTCP ? "over TCP" : "")<<endl;
@@ -746,6 +746,10 @@ int SyncRes::doResolveAt(set<string, CIStringCompare> nameservers, string auth,
 
       // reap all answers from this packet that are acceptable
       for(LWResult::res_t::const_iterator i=lwr.d_result.begin();i != lwr.d_result.end();++i) {
+	if(i->qtype.getCode() == QType::OPT) {
+	  LOG<<prefix<<qname<<": skipping OPT answer '"<<i->qname<<"' from '"<<auth<<"' nameservers" <<endl;
+	  continue;
+	}
 	LOG<<prefix<<qname<<": accept answer '"<<i->qname<<"|"<<i->qtype.getName()<<"|"<<i->content<<"' from '"<<auth<<"' nameservers? ";
 	if(i->qtype.getCode()==QType::ANY) {
 	  LOG<<"NO! - we don't accept 'ANY' data"<<endl;
diff --git a/pdns/syncres.hh b/pdns/syncres.hh
index 1c38b3e3f8..bc80d89969 100644
--- a/pdns/syncres.hh
+++ b/pdns/syncres.hh
@@ -212,7 +212,7 @@ class SyncRes
 public:
   explicit SyncRes(const struct timeval& now) :  d_outqueries(0), d_tcpoutqueries(0), d_throttledqueries(0), d_timeouts(0), d_unreachables(0),
 						 d_now(now),
-						 d_cacheonly(false), d_nocache(false) { }
+						 d_cacheonly(false), d_nocache(false), d_doEDNS0(false) { }
   int beginResolve(const string &qname, const QType &qtype, uint16_t qclass, vector<DNSResourceRecord>&ret);
   void setId(int id)
   {
@@ -231,6 +231,12 @@ public:
   {
     d_nocache=state;
   }
+
+  void setDoEDNS0(bool state=true)
+  {
+    d_doEDNS0=state;
+  }
+
   static unsigned int s_queries;
   static unsigned int s_outgoingtimeouts;
   static unsigned int s_throttledqueries;
@@ -372,6 +378,7 @@ private:
   static bool s_log;
   bool d_cacheonly;
   bool d_nocache;
+  bool d_doEDNS0;
 
   struct GetBestNSAnswer
   {
-- 
2.39.5