From 8290ad9f7a47edc0594ca13bbe45e8efd476def5 Mon Sep 17 00:00:00 2001
From: bert hubert <bert.hubert@netherlabs.nl>
Date: Thu, 28 May 2015 14:34:59 +0200
Subject: [PATCH] spread support for reporting udp packet drops from auth to
 recursor - needs documentation!

---
 pdns/dynhandler.cc      | 26 --------------------------
 pdns/misc.cc            | 30 ++++++++++++++++++++++++++++++
 pdns/misc.hh            |  1 +
 pdns/rec_channel_rec.cc |  7 +++++++
 4 files changed, 38 insertions(+), 26 deletions(-)

diff --git a/pdns/dynhandler.cc b/pdns/dynhandler.cc
index fa7651ac6..b0e8d0126 100644
--- a/pdns/dynhandler.cc
+++ b/pdns/dynhandler.cc
@@ -324,32 +324,6 @@ string DLReloadHandler(const vector<string>&parts, Utility::pid_t ppid)
   return "Ok";
 }
 
-uint64_t udpErrorStats(const std::string& str)
-{
-  ifstream ifs("/proc/net/snmp");
-  if(!ifs)
-    return 0;
-  string line;
-  vector<string> parts;
-  while(getline(ifs,line)) {
-    if(boost::starts_with(line, "Udp: ") && isdigit(line[5])) {
-      stringtok(parts, line, " \n\t\r");
-      if(parts.size() < 7)
-	break;
-      if(str=="udp-rcvbuf-errors")
-	return boost::lexical_cast<uint64_t>(parts[5]);
-      else if(str=="udp-sndbuf-errors")
-	return boost::lexical_cast<uint64_t>(parts[6]);
-      else if(str=="udp-noport-errors")
-	return boost::lexical_cast<uint64_t>(parts[2]);
-      else if(str=="udp-in-errors")
-	return boost::lexical_cast<uint64_t>(parts[3]);
-      else
-	return 0;
-    }
-  }
-  return 0;
-}
 
 string DLListZones(const vector<string>&parts, Utility::pid_t ppid)
 {
diff --git a/pdns/misc.cc b/pdns/misc.cc
index 8d3a8b4ba..77461b987 100644
--- a/pdns/misc.cc
+++ b/pdns/misc.cc
@@ -33,6 +33,7 @@
 #include <netinet/in.h>
 #include <sys/un.h>
 #include <unistd.h>
+#include <fstream>
 #include "misc.hh"
 #include <vector>
 #include <sstream>
@@ -971,3 +972,32 @@ bool setCloseOnExec(int sock)
   return true;
 }
 
+// please feel free to add other operating systems here. What we need are stats on dropped UDP packets
+uint64_t udpErrorStats(const std::string& str)
+{
+#ifdef __linux__
+  ifstream ifs("/proc/net/snmp");
+  if(!ifs)
+    return 0;
+  string line;
+  vector<string> parts;
+  while(getline(ifs,line)) {
+    if(boost::starts_with(line, "Udp: ") && isdigit(line[5])) {
+      stringtok(parts, line, " \n\t\r");
+      if(parts.size() < 7)
+	break;
+      if(str=="udp-rcvbuf-errors")
+	return boost::lexical_cast<uint64_t>(parts[5]);
+      else if(str=="udp-sndbuf-errors")
+	return boost::lexical_cast<uint64_t>(parts[6]);
+      else if(str=="udp-noport-errors")
+	return boost::lexical_cast<uint64_t>(parts[2]);
+      else if(str=="udp-in-errors")
+	return boost::lexical_cast<uint64_t>(parts[3]);
+      else
+	return 0;
+    }
+  }
+#endif
+  return 0;
+}
diff --git a/pdns/misc.hh b/pdns/misc.hh
index 99632853d..6cd29f34d 100644
--- a/pdns/misc.hh
+++ b/pdns/misc.hh
@@ -553,4 +553,5 @@ bool setBlocking( int sock );
 bool setNonBlocking( int sock );
 int closesocket(int fd);
 bool setCloseOnExec(int sock);
+uint64_t udpErrorStats(const std::string& str);
 #endif
diff --git a/pdns/rec_channel_rec.cc b/pdns/rec_channel_rec.cc
index 1a1da6d9e..e61066417 100644
--- a/pdns/rec_channel_rec.cc
+++ b/pdns/rec_channel_rec.cc
@@ -556,6 +556,13 @@ RecursorControlParser::RecursorControlParser()
   addGetStat("chain-resends", &g_stats.chainResends);
   addGetStat("tcp-clients", boost::bind(TCPConnection::getCurrentConnections));
 
+#ifdef __linux__
+  addGetStat("udp-recvbuf-errors", boost::bind(udpErrorStats, "udp-recvbuf-errors"));
+  addGetStat("udp-sndbuf-errors", boost::bind(udpErrorStats, "udp-sndbuf-errors"));
+  addGetStat("udp-noport-errors", boost::bind(udpErrorStats, "udp-noport-errors"));
+  addGetStat("udp-in-errors", boost::bind(udpErrorStats, "udp-in-errors"));
+#endif
+
   addGetStat("edns-ping-matches", &g_stats.ednsPingMatches);
   addGetStat("edns-ping-mismatches", &g_stats.ednsPingMismatches);
 
-- 
2.50.0