Merge pull request #1182 from SaberUK/master+431

[user/henk/code/inspircd.git] / src / coremods / core_dns.cpp

diff --git a/src/coremods/core_dns.cpp b/src/coremods/core_dns.cpp
index da468af5fae273a4ace9e1c48f266d45aa5552a7..1e7f6afca9325fb66681299966db5fe1057aa49d 100644 (file)
--- a/src/coremods/core_dns.cpp
+++ b/src/coremods/core_dns.cpp
@@ -339,6 +339,10 @@ class MyManager : public Manager, public Timer, public EventHandler
 
        irc::sockets::sockaddrs myserver;
 
+       /** Maximum number of entries in cache
+        */
+       static const unsigned int MAX_CACHE_SIZE = 1000;
+
        static bool IsExpired(const Query& record, time_t now = ServerInstance->Time())
        {
                const ResourceRecord& req = record.answers[0];
@@ -374,6 +378,9 @@ class MyManager : public Manager, public Timer, public EventHandler
         */
        void AddCache(Query& r)
        {
+               if (cache.size() >= MAX_CACHE_SIZE)
+                       cache.clear();
+
                // 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)
@@ -383,6 +390,7 @@ class MyManager : public Manager, public Timer, public EventHandler
                                cachettl = rr.ttl;
                }
 
+               cachettl = std::min(cachettl, (unsigned int)5*60);
                ResourceRecord& rr = r.answers.front();
                // Set TTL to what we've determined to be the lowest
                rr.ttl = cachettl;
@@ -393,7 +401,7 @@ class MyManager : public Manager, public Timer, public EventHandler
  public:
        DNS::Request* requests[MAX_REQUEST_ID+1];
 
-       MyManager(Module* c) : Manager(c), Timer(3600, true)
+       MyManager(Module* c) : Manager(c), Timer(5*60, true)
        {
                for (unsigned int i = 0; i <= MAX_REQUEST_ID; ++i)
                        requests[i] = NULL;
@@ -650,7 +658,7 @@ class MyManager : public Manager, public Timer, public EventHandler
                return true;
        }
 
-       void Rehash(const std::string& dnsserver)
+       void Rehash(const std::string& dnsserver, std::string sourceaddr, unsigned int sourceport)
        {
                if (this->GetFd() > -1)
                {
@@ -674,8 +682,15 @@ class MyManager : public Manager, public Timer, public EventHandler
                        SocketEngine::NonBlocking(s);
 
                        irc::sockets::sockaddrs bindto;
-                       memset(&bindto, 0, sizeof(bindto));
-                       bindto.sa.sa_family = myserver.sa.sa_family;
+                       if (sourceaddr.empty())
+                       {
+                               // set a sourceaddr for irc::sockets::aptosa() based on the servers af type
+                               if (myserver.sa.sa_family == AF_INET)
+                                       sourceaddr = "0.0.0.0";
+                               else if (myserver.sa.sa_family == AF_INET6)
+                                       sourceaddr = "::";
+                       }
+                       irc::sockets::aptosa(sourceaddr, sourceport, bindto);
 
                        if (SocketEngine::Bind(this->GetFd(), bindto) < 0)
                        {
@@ -690,6 +705,9 @@ class MyManager : public Manager, public Timer, public EventHandler
                                SocketEngine::Close(this->GetFd());
                                this->SetFd(-1);
                        }
+
+                       if (bindto.sa.sa_family != myserver.sa.sa_family)
+                               ServerInstance->Logs->Log(MODNAME, LOG_SPARSE, "Nameserver address family differs from source address family - hostnames might not resolve");
                }
                else
                {
@@ -702,6 +720,8 @@ class ModuleDNS : public Module
 {
        MyManager manager;
        std::string DNSServer;
+       std::string SourceIP;
+       unsigned int SourcePort;
 
        void FindDNSServer()
        {
@@ -762,19 +782,27 @@ class ModuleDNS : public Module
        }
 
  public:
-       ModuleDNS() : manager(this)
+       ModuleDNS() : manager(this)
+               , SourcePort(0)
        {
        }
 
        void ReadConfig(ConfigStatus& status) CXX11_OVERRIDE
        {
                std::string oldserver = DNSServer;
-               DNSServer = ServerInstance->Config->ConfValue("dns")->getString("server");
+               const std::string oldip = SourceIP;
+               const unsigned int oldport = SourcePort;
+
+               ConfigTag* tag = ServerInstance->Config->ConfValue("dns");
+               DNSServer = tag->getString("server");
+               SourceIP = tag->getString("sourceip");
+               SourcePort = tag->getInt("sourceport", 0, 0, 65535);
+
                if (DNSServer.empty())
                        FindDNSServer();
 
-               if (oldserver != DNSServer)
-                       this->manager.Rehash(DNSServer);
+               if (oldserver != DNSServer || oldip != SourceIP || oldport != SourcePort)
+                       this->manager.Rehash(DNSServer, SourceIP, SourcePort);
        }
 
        void OnUnloadModule(Module* mod)