X-Git-Url: https://git.netwichtig.de/gitweb/?a=blobdiff_plain;f=src%2Fcoremods%2Fcore_dns.cpp;h=da468af5fae273a4ace9e1c48f266d45aa5552a7;hb=a876f2c58e2f6f2602ed27da09a6e9c40008a80c;hp=829351f04dceec1cc07ee37786ced76aaf1b9a85;hpb=bd1471bc08be28bc2554d35fdaeb078338b14266;p=user%2Fhenk%2Fcode%2Finspircd.git

diff --git a/src/coremods/core_dns.cpp b/src/coremods/core_dns.cpp
index 829351f04..da468af5f 100644
--- a/src/coremods/core_dns.cpp
+++ b/src/coremods/core_dns.cpp
@@ -27,6 +27,13 @@
 #pragma comment(lib, "Iphlpapi.lib")
 #endif
 
+namespace DNS
+{
+	/** Maximum value of a dns request id, 16 bits wide, 0xFFFF.
+	 */
+	const unsigned int MAX_REQUEST_ID = 0xFFFF;
+}
+
 using namespace DNS;
 
 /** A full packet sent or recieved to/from the nameserver
@@ -367,7 +374,18 @@ class MyManager : public Manager, public Timer, public EventHandler
 	 */
 	void AddCache(Query& r)
 	{
-		const ResourceRecord& rr = r.answers[0];
+		// Determine the lowest TTL value and use that as the TTL of the cache entry
+		unsigned int cachettl = UINT_MAX;
+		for (std::vector<ResourceRecord>::const_iterator i = r.answers.begin(); i != r.answers.end(); ++i)
+		{
+			const ResourceRecord& rr = *i;
+			if (rr.ttl < cachettl)
+				cachettl = rr.ttl;
+		}
+
+		ResourceRecord& rr = r.answers.front();
+		// Set TTL to what we've determined to be the lowest
+		rr.ttl = cachettl;
 		ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "cache: added cache for " + rr.name + " -> " + rr.rdata + " ttl: " + ConvToStr(rr.ttl));
 		this->cache[r.question] = r;
 	}
@@ -457,11 +475,15 @@ class MyManager : public Manager, public Timer, public EventHandler
 
 		if (SocketEngine::SendTo(this, buffer, len, 0, &this->myserver.sa, this->myserver.sa_size()) != len)
 			throw Exception("DNS: Unable to send query");
+
+		// Add timer for timeout
+		ServerInstance->Timers.AddTimer(req);
 	}
 
 	void RemoveRequest(DNS::Request* req)
 	{
-		this->requests[req->id] = NULL;
+		if (requests[req->id] == req)
+			requests[req->id] = NULL;
 	}
 
 	std::string GetErrorStr(Error e)
@@ -475,6 +497,7 @@ class MyManager : public Manager, public Timer, public EventHandler
 			case ERROR_NOT_AN_ANSWER:
 			case ERROR_NONSTANDARD_QUERY:
 			case ERROR_FORMAT_ERROR:
+			case ERROR_MALFORMED:
 				return "Malformed answer";
 			case ERROR_SERVER_FAILURE:
 			case ERROR_NOT_IMPLEMENTED:
@@ -517,17 +540,19 @@ class MyManager : public Manager, public Timer, public EventHandler
 		}
 
 		Packet recv_packet;
+		bool valid = false;
 
 		try
 		{
 			recv_packet.Fill(buffer, length);
+			valid = true;
 		}
 		catch (Exception& ex)
 		{
 			ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, ex.GetReason());
-			return;
 		}
 
+		// recv_packet.id must be filled in here
 		DNS::Request* request = this->requests[recv_packet.id];
 		if (request == NULL)
 		{
@@ -542,14 +567,20 @@ class MyManager : public Manager, public Timer, public EventHandler
 			return;
 		}
 
-		if (recv_packet.flags & QUERYFLAGS_OPCODE)
+		if (!valid)
+		{
+			ServerInstance->stats.DnsBad++;
+			recv_packet.error = ERROR_MALFORMED;
+			request->OnError(&recv_packet);
+		}
+		else if (recv_packet.flags & QUERYFLAGS_OPCODE)
 		{
 			ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Received a nonstandard query");
 			ServerInstance->stats.DnsBad++;
 			recv_packet.error = ERROR_NONSTANDARD_QUERY;
 			request->OnError(&recv_packet);
 		}
-		else if (recv_packet.flags & QUERYFLAGS_RCODE)
+		else if (!(recv_packet.flags & QUERYFLAGS_QR) || (recv_packet.flags & QUERYFLAGS_RCODE))
 		{
 			Error error = ERROR_UNKNOWN;
 
@@ -717,7 +748,7 @@ class ModuleDNS : public Module
 			if (DNSServer == "nameserver")
 			{
 				resolv >> DNSServer;
-				if (DNSServer.find_first_not_of("0123456789.") == std::string::npos)
+				if (DNSServer.find_first_not_of("0123456789.") == std::string::npos || DNSServer.find_first_not_of("0123456789ABCDEFabcdef:") == std::string::npos)
 				{
 					ServerInstance->Logs->Log("CONFIG", LOG_DEFAULT, "<dns:server> set to '%s' as first resolver in /etc/resolv.conf.",DNSServer.c_str());
 					return;