using namespace std;
-#include <string>
-#include <time.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <errno.h>
-#include <sys/types.h>
-#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
-#include <map>
#include "dns.h"
#include "inspircd.h"
-#include "helperfuncs.h"
-#include "inspircd_config.h"
#include "socketengine.h"
#include "configreader.h"
+#include "socket.h"
-/* We need these */
-extern InspIRCd* ServerInstance;
-extern ServerConfig* Config;
-
-/* Master file descriptor */
-int DNS::MasterSocket;
+using namespace std;
+using irc::sockets::insp_sockaddr;
+using irc::sockets::insp_inaddr;
+using irc::sockets::insp_ntoa;
+using irc::sockets::insp_aton;
-/* Masks to mask off the responses we get from the DNSRequest methods */
+/** Masks to mask off the responses we get from the DNSRequest methods
+ */
enum QueryInfo
{
ERROR_MASK = 0x10000 /* Result is an error */
};
-/* Flags which can be ORed into a request or reply for different meanings */
+/** Flags which can be ORed into a request or reply for different meanings
+ */
enum QueryFlags
{
FLAGS_MASK_RD = 0x01, /* Recursive */
};
-/* Represents a dns resource record (rr) */
+/** Represents a dns resource record (rr)
+ */
class ResourceRecord
{
public:
unsigned int rdlength; /* Record length */
};
-/* Represents a dns request/reply header, and its payload as opaque data.
+/** Represents a dns request/reply header, and its payload as opaque data.
*/
class DNSHeader
{
unsigned char payload[512]; /* Packet payload */
};
-/* Represents a request 'on the wire' with routing information relating to
+/** Represents a request 'on the wire' with routing information relating to
* where to call when we get a result
*/
class DNSRequest
unsigned int rr_class; /* Request class */
QueryType type; /* Request type */
insp_inaddr myserver; /* DNS server address*/
+ DNS* dnsobj; /* DNS caller (where we get our FD from) */
/* Allocate the processing buffer */
- DNSRequest(insp_inaddr server)
+ DNSRequest(DNS* dns, insp_inaddr server) : dnsobj(dns)
{
res = new unsigned char[512];
*res = 0;
int SendRequests(const DNSHeader *header, const int length, QueryType qt);
};
-/* Fill a ResourceRecord class based on raw data input */
+/** Fill a ResourceRecord class based on raw data input */
inline void DNS::FillResourceRecord(ResourceRecord* rr, const unsigned char *input)
{
rr->type = (QueryType)((input[0] << 8) + input[1]);
rr->rdlength = (input[8] << 8) + input[9];
}
-/* Fill a DNSHeader class based on raw data input of a given length */
+/** Fill a DNSHeader class based on raw data input of a given length */
inline void DNS::FillHeader(DNSHeader *header, const unsigned char *input, const int length)
{
header->id[0] = input[0];
memcpy(header->payload,&input[12],length);
}
-/* Empty a DNSHeader class out into raw data, ready for transmission */
+/** Empty a DNSHeader class out into raw data, ready for transmission */
inline void DNS::EmptyHeader(unsigned char *output, const DNSHeader *header, const int length)
{
output[0] = header->id[0];
memcpy(&output[12],header->payload,length);
}
-/* Send requests we have previously built down the UDP socket */
+/** Send requests we have previously built down the UDP socket */
int DNSRequest::SendRequests(const DNSHeader *header, const int length, QueryType qt)
{
insp_sockaddr addr;
addr.sin_family = AF_FAMILY;
addr.sin_port = htons(DNS::QUERY_PORT);
#endif
- if (sendto(DNS::GetMasterSocket(), payload, length + 12, 0, (sockaddr *) &addr, sizeof(addr)) == -1)
- {
- log(DEBUG,"Error in sendto! (%s)",strerror(errno));
+ if (sendto(dnsobj->GetFd(), payload, length + 12, 0, (sockaddr *) &addr, sizeof(addr)) == -1)
return -1;
- }
return 0;
}
-/* Add a query with a predefined header, and allocate an ID for it. */
+/** Add a query with a predefined header, and allocate an ID for it. */
DNSRequest* DNS::AddQuery(DNSHeader *header, int &id)
{
+ /* Is the DNS connection down? */
+ if (this->GetFd() == -1)
+ return NULL;
+
/* Are there already the max number of requests on the go? */
if (requests.size() == DNS::MAX_REQUEST_ID + 1)
return NULL;
while (requests.find(id) != requests.end())
id = this->PRNG() & DNS::MAX_REQUEST_ID;
- DNSRequest* req = new DNSRequest(this->myserver);
+ DNSRequest* req = new DNSRequest(this, this->myserver);
header->id[0] = req->id[0] = id >> 8;
header->id[1] = req->id[1] = id & 0xFF;
return req;
}
-int DNS::GetMasterSocket()
+/** Initialise the DNS UDP socket so that we can send requests */
+DNS::DNS(InspIRCd* Instance) : ServerInstance(Instance)
{
- return MasterSocket;
-}
+ ServerInstance->Log(DEBUG,"DNS::DNS: Instance = %08x",Instance);
-/* Initialise the DNS UDP socket so that we can send requests */
-DNS::DNS()
-{
insp_inaddr addr;
/* Clear the Resolver class table */
*/
currid = 0;
+ /* By default we're not munging ip's
+ */
+ ip6munge = false;
+
/* Clear the namesever address */
memset(&myserver,0,sizeof(insp_inaddr));
/* Convert the nameserver address into an insp_inaddr */
- if (insp_aton(Config->DNSServer,&addr) > 0)
+ if (insp_aton(ServerInstance->Config->DNSServer,&addr) > 0)
{
memcpy(&myserver,&addr,sizeof(insp_inaddr));
- log(DEBUG,"Added nameserver '%s'",Config->DNSServer);
+ if ((strstr(ServerInstance->Config->DNSServer,"::ffff:") == (char*)&ServerInstance->Config->DNSServer) || (strstr(ServerInstance->Config->DNSServer,"::FFFF:") == (char*)&ServerInstance->Config->DNSServer))
+ {
+ /* These dont come back looking like they did when they went in.
+ * We're forced to turn some checks off.
+ * If anyone knows how to fix this, let me know. --Brain
+ */
+ ServerInstance->Log(DEFAULT,"WARNING: Using IPv4 addresses over IPv6 forces some DNS checks to be disabled.");
+ ServerInstance->Log(DEFAULT," This should not cause a problem, however it is recommended you migrate");
+ ServerInstance->Log(DEFAULT," to a true IPv6 environment.");
+ this->ip6munge = true;
+ }
+ ServerInstance->Log(DEBUG,"Added nameserver '%s'",ServerInstance->Config->DNSServer);
}
else
{
- log(DEBUG,"GACK! insp_aton says the nameserver '%s' is invalid!",Config->DNSServer);
+ ServerInstance->Log(DEBUG,"GACK! insp_aton says the nameserver '%s' is invalid!",ServerInstance->Config->DNSServer);
}
/* Initialize mastersocket */
- MasterSocket = socket(PF_PROTOCOL, SOCK_DGRAM, 0);
- if (MasterSocket != -1)
+ this->SetFd(socket(PF_PROTOCOL, SOCK_DGRAM, 0));
+ if (this->GetFd() != -1)
{
/* Did it succeed? */
- if (fcntl(MasterSocket, F_SETFL, O_NONBLOCK) != 0)
+ if (fcntl(this->GetFd(), F_SETFL, O_NONBLOCK) != 0)
{
/* Couldn't make the socket nonblocking */
- shutdown(MasterSocket,2);
- close(MasterSocket);
- MasterSocket = -1;
+ shutdown(this->GetFd(),2);
+ close(this->GetFd());
+ this->SetFd(-1);
}
}
+ else
+ {
+ ServerInstance->Log(DEBUG,"I cant socket() this socket! (%s)",strerror(errno));
+ }
/* Have we got a socket and is it nonblocking? */
- if (MasterSocket != -1)
+ if (this->GetFd() != -1)
{
#ifdef IPV6
insp_sockaddr addr;
memset(&addr,0,sizeof(addr));
addr.sin6_family = AF_FAMILY;
addr.sin6_port = 0;
- memset(&addr.sin6_addr,255,sizeof(in6_addr));
+ addr.sin6_addr = in6addr_any;
#else
insp_sockaddr addr;
memset(&addr,0,sizeof(addr));
addr.sin_addr.s_addr = INADDR_ANY;
#endif
/* Bind the port */
- if (bind(MasterSocket,(sockaddr *)&addr,sizeof(addr)) != 0)
+ if (bind(this->GetFd(),(sockaddr *)&addr,sizeof(addr)) != 0)
{
/* Failed to bind */
- log(DEBUG,"Cant bind DNS::MasterSocket");
- shutdown(MasterSocket,2);
- close(MasterSocket);
- MasterSocket = -1;
+ ServerInstance->Log(DEBUG,"Cant bind DNS fd");
+ shutdown(this->GetFd(),2);
+ close(this->GetFd());
+ this->SetFd(-1);
}
- if (MasterSocket >= 0)
+ if (this->GetFd() >= 0)
{
+ ServerInstance->Log(DEBUG,"Add master socket %d",this->GetFd());
/* Hook the descriptor into the socket engine */
if (ServerInstance && ServerInstance->SE)
- ServerInstance->SE->AddFd(MasterSocket,true,X_ESTAB_DNS);
+ {
+ if (!ServerInstance->SE->AddFd(this))
+ {
+ ServerInstance->Log(DEFAULT,"Internal error starting DNS - hostnames will NOT resolve.");
+ shutdown(this->GetFd(),2);
+ close(this->GetFd());
+ this->SetFd(-1);
+ }
+ }
}
}
}
-/* Build a payload to be placed after the header, based upon input data, a resource type, a class and a pointer to a buffer */
+/** Build a payload to be placed after the header, based upon input data, a resource type, a class and a pointer to a buffer */
int DNS::MakePayload(const char * const name, const QueryType rr, const unsigned short rr_class, unsigned char * const payload)
{
short payloadpos = 0;
return payloadpos + 4;
}
-/* Start lookup of an hostname to an IP address */
+/** Start lookup of an hostname to an IP address */
int DNS::GetIP(const char *name)
{
DNSHeader h;
return id;
}
-/* Start lookup of an hostname to an IPv6 address */
+/** Start lookup of an hostname to an IPv6 address */
int DNS::GetIP6(const char *name)
{
DNSHeader h;
return id;
}
-/* Start lookup of a cname to another name */
+/** Start lookup of a cname to another name */
int DNS::GetCName(const char *alias)
{
DNSHeader h;
return id;
}
-/* Start lookup of an IP address to a hostname */
+/** Start lookup of an IP address to a hostname */
int DNS::GetName(const insp_inaddr *ip)
{
char query[128];
return id;
}
-/* Start lookup of an IP address to a hostname */
+/** Start lookup of an IP address to a hostname */
int DNS::GetNameForce(const char *ip, ForceProtocol fp)
{
char query[128];
DNSHeader h;
int id;
int length;
-
+#ifdef SUPPORT_IP6LINKS
if (fp == PROTOCOL_IPV6)
{
in6_addr i;
return -1;
}
else
+#endif
{
in_addr i;
if (inet_aton(ip, &i))
return -1;
}
- log(DEBUG,"DNS::GetNameForce: %s %d",query, fp);
+ ServerInstance->Log(DEBUG,"DNS::GetNameForce: %s %d",query, fp);
if ((length = this->MakePayload(query, DNS_QUERY_PTR, 1, (unsigned char*)&h.payload)) == -1)
return -1;
return id;
}
+/** Build an ipv6 reverse domain from an in6_addr
+ */
void DNS::MakeIP6Int(char* query, const in6_addr *ip)
{
+#ifdef SUPPORT_IP6LINKS
const char* hex = "0123456789abcdef";
for (int index = 31; index >= 0; index--) /* for() loop steps twice per byte */
{
*query++ = '.'; /* Seperator */
}
strcpy(query,"ip6.arpa"); /* Suffix the string */
+#else
+ *query = 0;
+#endif
}
-/* Return the next id which is ready, and the result attached to it */
+/** Return the next id which is ready, and the result attached to it */
DNSResult DNS::GetResult()
{
/* Fetch dns query response and decide where it belongs */
const char* ipaddr_from = "";
unsigned short int port_from = 0;
- int length = recvfrom(MasterSocket,buffer,sizeof(DNSHeader),0,&from,&x);
+ int length = recvfrom(this->GetFd(),buffer,sizeof(DNSHeader),0,&from,&x);
if (length < 0)
- log(DEBUG,"Error in recvfrom()! (%s)",strerror(errno));
+ ServerInstance->Log(DEBUG,"Error in recvfrom()! (%s)",strerror(errno));
/* Did we get the whole header? */
if (length < 12)
+ {
/* Nope - something screwed up. */
+ ServerInstance->Log(DEBUG,"Whole header not read!");
return std::make_pair(-1,"");
+ }
/* Check wether the reply came from a different DNS
* server to the one we sent it to, or the source-port
port_from = ntohs(((sockaddr_in*)&from)->sin_port);
#endif
- if ((port_from != DNS::QUERY_PORT) || (strcasecmp(ipaddr_from, Config->DNSServer)))
- return std::make_pair(-1,"");
+ /* 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)))
+ {
+ ServerInstance->Log(DEBUG,"port %d is not 53, or %s is not %s",port_from, ipaddr_from, ServerInstance->Config->DNSServer);
+ return std::make_pair(-1,"");
+ }
+ }
/* Put the read header info into a header class */
DNS::FillHeader(&header,buffer,length - 12);
if (n_iter == requests.end())
{
/* Somehow we got a DNS response for a request we never made... */
- log(DEBUG,"DNS: got a response for a query we didnt send with fd=%d queryid=%d",MasterSocket,this_id);
+ ServerInstance->Log(DEBUG,"DNS: got a response for a query we didnt send with fd=%d queryid=%d",this->GetFd(),this_id);
return std::make_pair(-1,"");
}
else
memmove(formatted,formatted + 1, strlen(formatted + 1) + 1);
}
resultstr = formatted;
+
+ /* Special case. Sending ::1 around between servers
+ * and to clients is dangerous, because the : on the
+ * start makes the client or server interpret the IP
+ * as the last parameter on the line with a value ":1".
+ */
+ if (*formatted == ':')
+ resultstr = "0" + resultstr;
}
break;
break;
default:
- log(DEBUG,"WARNING: Somehow we made a request for a DNS_QUERY_PTR4 or DNS_QUERY_PTR6, but these arent real rr types!");
+ ServerInstance->Log(DEBUG,"WARNING: Somehow we made a request for a DNS_QUERY_PTR4 or DNS_QUERY_PTR6, but these arent real rr types!");
break;
}
}
}
-/* A result is ready, process it */
+/** A result is ready, process it */
DNSInfo DNSRequest::ResultIsReady(DNSHeader &header, int length)
{
int i = 0;
return std::make_pair(res,"No error");;
}
-/* Close the master socket */
+/** Close the master socket */
DNS::~DNS()
{
- shutdown(MasterSocket, 2);
- close(MasterSocket);
+ shutdown(this->GetFd(), 2);
+ close(this->GetFd());
}
-/* High level abstraction of dns used by application at large */
-Resolver::Resolver(const std::string &source, QueryType qt) : input(source), querytype(qt)
+/** High level abstraction of dns used by application at large */
+Resolver::Resolver(InspIRCd* Instance, const std::string &source, QueryType qt) : ServerInstance(Instance), input(source), querytype(qt)
{
+ ServerInstance->Log(DEBUG,"Instance: %08x %08x",Instance, ServerInstance);
+
insp_inaddr binip;
switch (querytype)
}
if (this->myid == -1)
{
- log(DEBUG,"Resolver::Resolver: Could not get an id!");
+ ServerInstance->Log(DEBUG,"Resolver::Resolver: Could not get an id!");
this->OnError(RESOLVER_NSDOWN, "Nameserver is down");
throw ModuleException("Resolver: Couldnt get an id to make a request");
/* We shouldnt get here really */
return;
}
- log(DEBUG,"Resolver::Resolver: this->myid=%d",this->myid);
+ ServerInstance->Log(DEBUG,"Resolver::Resolver: this->myid=%d",this->myid);
}
+/** Called when an error occurs */
void Resolver::OnError(ResolverError e, const std::string &errormessage)
{
/* Nothing in here */
}
+/** Destroy a resolver */
Resolver::~Resolver()
{
/* Nothing here (yet) either */
}
-/* Get the request id associated with this class */
+/** Get the request id associated with this class */
int Resolver::GetId()
{
return this->myid;
}
-/* Process a socket read event */
-void DNS::MarshallReads(int fd)
+/** Process a socket read event */
+void DNS::HandleEvent(EventType et)
{
- /* We are only intrested in our single fd */
- if (fd == GetMasterSocket())
+ ServerInstance->Log(DEBUG,"Marshall reads: %d",this->GetFd());
+ /* Fetch the id and result of the next available packet */
+ DNSResult res = this->GetResult();
+ /* Is there a usable request id? */
+ if (res.first != -1)
{
- /* Fetch the id and result of the next available packet */
- DNSResult res = this->GetResult();
- /* Is there a usable request id? */
- if (res.first != -1)
+ /* Its an error reply */
+ if (res.first & ERROR_MASK)
{
- /* Its an error reply */
- if (res.first & ERROR_MASK)
+ /* Mask off the error bit */
+ res.first -= ERROR_MASK;
+ /* Marshall the error to the correct class */
+ ServerInstance->Log(DEBUG,"Error available, id=%d",res.first);
+ if (Classes[res.first])
{
- /* Mask off the error bit */
- res.first -= ERROR_MASK;
-
- /* Marshall the error to the correct class */
- log(DEBUG,"Error available, id=%d",res.first);
- if (Classes[res.first])
- {
- if (ServerInstance && ServerInstance->stats)
- ServerInstance->stats->statsDnsBad++;
- Classes[res.first]->OnError(RESOLVER_NXDOMAIN, res.second);
- delete Classes[res.first];
- Classes[res.first] = NULL;
- }
+ if (ServerInstance && ServerInstance->stats)
+ ServerInstance->stats->statsDnsBad++;
+ Classes[res.first]->OnError(RESOLVER_NXDOMAIN, res.second);
+ delete Classes[res.first];
+ Classes[res.first] = NULL;
}
- else
+ }
+ else
+ {
+ /* It is a non-error result */
+ ServerInstance->Log(DEBUG,"Result available, id=%d",res.first);
+ /* Marshall the result to the correct class */
+ if (Classes[res.first])
{
- /* It is a non-error result */
- log(DEBUG,"Result available, id=%d",res.first);
- /* Marshall the result to the correct class */
- if (Classes[res.first])
- {
- if (ServerInstance && ServerInstance->stats)
- ServerInstance->stats->statsDnsGood++;
- Classes[res.first]->OnLookupComplete(res.second);
- delete Classes[res.first];
- Classes[res.first] = NULL;
- }
+ if (ServerInstance && ServerInstance->stats)
+ ServerInstance->stats->statsDnsGood++;
+ Classes[res.first]->OnLookupComplete(res.second);
+ delete Classes[res.first];
+ Classes[res.first] = NULL;
}
-
- if (ServerInstance && ServerInstance->stats)
- ServerInstance->stats->statsDns++;
-
}
+
+ if (ServerInstance && ServerInstance->stats)
+ ServerInstance->stats->statsDns++;
}
}
-/* Add a derived Resolver to the working set */
+/** Add a derived Resolver to the working set */
bool DNS::AddResolverClass(Resolver* r)
{
/* Check the pointers validity and the id's validity */
}
}
+/** Generate pseudo-random number */
unsigned long DNS::PRNG()
{
unsigned long val = 0;