From 84e1142d448827a7c89e26032b9b43cad9079c4b Mon Sep 17 00:00:00 2001
From: Pieter Lexis <pieter.lexis@powerdns.com>
Date: Tue, 1 Dec 2015 17:19:56 +0100
Subject: [PATCH] Add a `lenField` option to xfrText()

This option (true by default) tells the writer/parser to add/read a
byte that is the length of the data following.
---
 pdns/dnsparser.cc    |  8 ++++++--
 pdns/dnsparser.hh    |  6 +++---
 pdns/dnswriter.cc    | 10 ++++++++--
 pdns/dnswriter.hh    |  2 +-
 pdns/rcpgenerator.cc |  4 ++--
 pdns/rcpgenerator.hh |  4 ++--
 6 files changed, 22 insertions(+), 12 deletions(-)

diff --git a/pdns/dnsparser.cc b/pdns/dnsparser.cc
index 499ddea21..405933c83 100644
--- a/pdns/dnsparser.cc
+++ b/pdns/dnsparser.cc
@@ -439,7 +439,7 @@ static string txtEscape(const string &name)
 }
 
 // exceptions thrown here do not result in logging in the main pdns auth server - just so you know!
-string PacketReader::getText(bool multi)
+string PacketReader::getText(bool multi, bool lenField)
 {
   string ret;
   ret.reserve(40);
@@ -447,7 +447,11 @@ string PacketReader::getText(bool multi)
     if(!ret.empty()) {
       ret.append(1,' ');
     }
-    unsigned char labellen=d_content.at(d_pos++);
+    uint16_t labellen;
+    if(lenField)
+      labellen=d_content.at(d_pos++);
+    else
+      labellen=d_recordlen - (d_pos - d_startrecordpos);
     
     ret.append(1,'"');
     if(labellen) { // no need to do anything for an empty string
diff --git a/pdns/dnsparser.hh b/pdns/dnsparser.hh
index 88e02d3dd..96f0906c0 100644
--- a/pdns/dnsparser.hh
+++ b/pdns/dnsparser.hh
@@ -124,9 +124,9 @@ public:
     name=getName();
   }
 
-  void xfrText(string &text, bool multi=false)
+  void xfrText(string &text, bool multi=false, bool lenField=true)
   {
-    text=getText(multi);
+    text=getText(multi, lenField);
   }
 
   void xfrBlob(string& blob);
@@ -141,7 +141,7 @@ public:
   void copyRecord(unsigned char* dest, uint16_t len);
 
   DNSName getName();
-  string getText(bool multi);
+  string getText(bool multi, bool lenField);
 
   uint16_t d_pos;
 
diff --git a/pdns/dnswriter.cc b/pdns/dnswriter.cc
index 8dd1dbb99..06dc3b980 100644
--- a/pdns/dnswriter.cc
+++ b/pdns/dnswriter.cc
@@ -146,14 +146,19 @@ void DNSPacketWriter::xfr8BitInt(uint8_t val)
 
 
 /* input:
+ if lenField is true
   "" -> 0
   "blah" -> 4blah
   "blah" "blah" -> output 4blah4blah
   "verylongstringlongerthan256....characters" \xffverylongstring\x23characters (autosplit)
   "blah\"blah" -> 9blah"blah
   "blah\97" -> 5blahb
+
+ if lenField is false
+  "blah" -> blah
+  "blah\"blah" -> blah"blah
   */
-void DNSPacketWriter::xfrText(const string& text, bool)
+void DNSPacketWriter::xfrText(const string& text, bool, bool lenField)
 {
   if(text.empty()) {
     d_record.push_back(0);
@@ -161,7 +166,8 @@ void DNSPacketWriter::xfrText(const string& text, bool)
   }
   vector<string> segments = segmentDNSText(text);
   for(const string& str :  segments) {
-    d_record.push_back(str.length());
+    if(lenField)
+      d_record.push_back(str.length());
     d_record.insert(d_record.end(), str.c_str(), str.c_str() + str.length());
   }
 }
diff --git a/pdns/dnswriter.hh b/pdns/dnswriter.hh
index c5554ef7e..2936890e4 100644
--- a/pdns/dnswriter.hh
+++ b/pdns/dnswriter.hh
@@ -87,7 +87,7 @@ public:
   void xfr8BitInt(uint8_t val);
 
   void xfrName(const DNSName& label, bool compress=false, bool noDot=false);
-  void xfrText(const string& text, bool multi=false);
+  void xfrText(const string& text, bool multi=false, bool lenField=true);
   void xfrBlob(const string& blob, int len=-1);
   void xfrBlobNoSpaces(const string& blob, int len=-1);
   void xfrHexBlob(const string& blob, bool keepReading=false);
diff --git a/pdns/rcpgenerator.cc b/pdns/rcpgenerator.cc
index dd34186de..495d88972 100644
--- a/pdns/rcpgenerator.cc
+++ b/pdns/rcpgenerator.cc
@@ -333,7 +333,7 @@ void RecordTextWriter::xfrBase32HexBlob(const string& val)
 }
 
 
-void RecordTextReader::xfrText(string& val, bool multi)
+void RecordTextReader::xfrText(string& val, bool multi, bool lenField)
 {
   val.clear();
   val.reserve(d_end - d_pos);
@@ -547,7 +547,7 @@ void RecordTextWriter::xfrHexBlob(const string& val, bool)
   }
 }
 
-void RecordTextWriter::xfrText(const string& val, bool multi)
+void RecordTextWriter::xfrText(const string& val, bool multi, bool lenField)
 {
   if(!d_string.empty())
     d_string.append(1,' ');
diff --git a/pdns/rcpgenerator.hh b/pdns/rcpgenerator.hh
index f5af2ea64..5b33a01b4 100644
--- a/pdns/rcpgenerator.hh
+++ b/pdns/rcpgenerator.hh
@@ -53,7 +53,7 @@ public:
   void xfrTime(uint32_t& val);
 
   void xfrName(DNSName& val, bool compress=false, bool noDot=false);
-  void xfrText(string& val, bool multi=false);
+  void xfrText(string& val, bool multi=false, bool lenField=true);
   void xfrHexBlob(string& val, bool keepReading=false);
   void xfrBase32HexBlob(string& val);
 
@@ -84,7 +84,7 @@ public:
 
   void xfrType(const uint16_t& val);
   void xfrName(const DNSName& val, bool compress=false, bool noDot=false);
-  void xfrText(const string& val, bool multi=false);
+  void xfrText(const string& val, bool multi=false, bool lenField=true);
   void xfrBlobNoSpaces(const string& val, int len=-1);
   void xfrBlob(const string& val, int len=-1);
   void xfrHexBlob(const string& val, bool keepReading=false);
-- 
2.40.0