Fix null dereference caused by tracking dummy

[user/henk/code/inspircd.git] / src / dns.cpp

diff --git a/src/dns.cpp b/src/dns.cpp
index a28881ad2f4d00667ad5d722d9bc88a0e8f78cd1..e4d0b73fb9c6307e67931c085c42d7bd176727d3 100644 (file)
--- a/src/dns.cpp
+++ b/src/dns.cpp
@@ -31,7 +31,6 @@ looks like this, walks like this or tastes like this.
 #include <arpa/inet.h>
 #else
 #include "inspircd_win32wrapper.h"
-#include "inspircd_se_config.h"
 #endif
 
 #include "inspircd.h"
@@ -217,26 +216,8 @@ int DNSRequest::SendRequests(const DNSHeader *header, const int length, QueryTyp
 
        DNS::EmptyHeader(payload,header,length);
 
-       if (this->dnsobj->socketfamily == AF_INET6)
-       {
-               sockaddr_in6 addr;
-               memset(&addr,0,sizeof(addr));
-               memcpy(&addr.sin6_addr,&dnsobj->myserver6,sizeof(addr.sin6_addr));
-               addr.sin6_family = AF_INET6;
-               addr.sin6_port = htons(DNS::QUERY_PORT);
-               if (ServerInstance->SE->SendTo(dnsobj, payload, length + 12, 0, (sockaddr *) &addr, sizeof(addr)) != length+12)
-                       return -1;
-       }
-       else
-       {
-               sockaddr_in addr;
-               memset(&addr,0,sizeof(addr));
-               memcpy(&addr.sin_addr.s_addr,&dnsobj->myserver4,sizeof(addr.sin_addr));
-               addr.sin_family = AF_INET;
-               addr.sin_port = htons(DNS::QUERY_PORT);
-               if (ServerInstance->SE->SendTo(dnsobj, (const char*)payload, length + 12, 0, (sockaddr *) &addr, sizeof(addr)) != length+12)
-                       return -1;
-       }
+       if (ServerInstance->SE->SendTo(dnsobj, payload, length + 12, 0, &(dnsobj->myserver.sa), sa_size(dnsobj->myserver)) != length+12)
+               return -1;
 
        ServerInstance->Logs->Log("RESOLVER",DEBUG,"Sent OK");
        return 0;
@@ -303,7 +284,6 @@ int DNS::PruneCache()
 
 void DNS::Rehash()
 {
-       ip6munge = false;
        int portpass = 0;
 
        if (this->GetFd() > -1)
@@ -323,25 +303,7 @@ void DNS::Rehash()
                this->cache = new dnscache();
        }
 
-       if ((strstr(ServerInstance->Config->DNSServer,"::ffff:") == (char*)&ServerInstance->Config->DNSServer) ||  (strstr(ServerInstance->Config->DNSServer,"::FFFF:") == (char*)&ServerInstance->Config->DNSServer))
-       {
-               ServerInstance->Logs->Log("RESOLVER",DEFAULT,"WARNING: Using IPv4 addresses over IPv6 forces some DNS checks to be disabled.");
-               ServerInstance->Logs->Log("RESOLVER",DEFAULT,"         This should not cause a problem, however it is recommended you migrate");
-               ServerInstance->Logs->Log("RESOLVER",DEFAULT,"         to a true IPv6 environment.");
-               this->ip6munge = true;
-       }
-
-       this->socketfamily = AF_INET;
-       if (strchr(ServerInstance->Config->DNSServer,':'))
-       {
-               this->socketfamily = AF_INET6;
-               inet_pton(AF_INET6, ServerInstance->Config->DNSServer, &this->myserver6);
-       }
-       else
-       {
-               inet_aton(ServerInstance->Config->DNSServer, &this->myserver4);
-               portpass = -1;
-       }
+       irc::sockets::aptosa(ServerInstance->Config->DNSServer, DNS::QUERY_PORT, &myserver);
 
        /* Initialize mastersocket */
        int s = irc::sockets::OpenTCPSocket(ServerInstance->Config->DNSServer, SOCK_DGRAM);
@@ -574,9 +536,8 @@ DNSResult DNS::GetResult()
        DNSRequest *req;
        unsigned char buffer[sizeof(DNSHeader)];
        irc::sockets::sockaddrs from;
-       socklen_t x = this->socketfamily == AF_INET ? sizeof(sockaddr_in) : sizeof(sockaddr_in6);
-       const char* ipaddr_from;
-       unsigned short int port_from = 0;
+       memset(&from, 0, sizeof(from));
+       socklen_t x = sizeof(from);
 
        int length = ServerInstance->SE->RecvFrom(this, (char*)buffer, sizeof(DNSHeader), 0, &from.sa, &x);
 
@@ -592,31 +553,13 @@ DNSResult DNS::GetResult()
         * is not 53.
         * A user could in theory still spoof dns packets anyway
         * but this is less trivial than just sending garbage
-        * to the client, which is possible without this check.
+        * to the server, which is possible without this check.
         *
         * -- Thanks jilles for pointing this one out.
         */
-       char nbuf[MAXBUF];
-       if (this->socketfamily == AF_INET6)
+       if (memcmp(&from, &myserver, sizeof(irc::sockets::sockaddrs)))
        {
-               ipaddr_from = inet_ntop(AF_INET6, &from.in6.sin6_addr, nbuf, sizeof(nbuf));
-               port_from = ntohs(from.in6.sin6_port);
-       }
-       else
-       {
-               ipaddr_from = inet_ntoa(from.in4.sin_addr);
-               port_from = ntohs(from.in4.sin_port);
-       }
-
-       /* We cant perform this security check if you're using 4in6.
-        * Tough luck to you, choose one or't other!
-        */
-       if (!ip6munge)
-       {
-               if ((port_from != DNS::QUERY_PORT) || (strcasecmp(ipaddr_from, ServerInstance->Config->DNSServer)))
-               {
-                       return DNSResult(-1,"",0,"");
-               }
+               return DNSResult(-1,"",0,"");
        }
 
        /* Put the read header info into a header class */