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;
-
-/* Query and resource record types */
-enum QueryType
-{
- DNS_QRY_A = 1, /* 'A' record: an IP address */
- DNS_QRY_PTR = 12 /* 'PTR' record: a hostname */
-};
+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 */
};
-/* Lookup table of Resolver classes. Because the request ID can be between
- * 0 and 65535 of these, we have 65536 of them. This could be a map, saving
- * some ram, but that will also slow down DNS requests, and the DNS request
- * mechanism needs to be pretty fast.
+/** Represents a dns resource record (rr)
*/
-Resolver* dns_classes[65536];
-
-/* 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
- * where to call when we get a result
- */
class DNSRequest
{
public:
- unsigned char id[2]; /* Request id */
- unsigned char* res; /* Result processing buffer */
- unsigned int rr_class; /* Request class */
- QueryType type; /* Request type */
- insp_inaddr myserver; /* DNS server address*/
-
- /* Allocate the processing buffer */
- DNSRequest(insp_inaddr server)
+ unsigned char id[2]; /* Request id */
+ unsigned char* res; /* Result processing buffer */
+ 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) */
+
+ DNSRequest(InspIRCd* Instance, DNS* dns, insp_inaddr server, int id, requestlist &requests);
+ ~DNSRequest();
+ DNSInfo ResultIsReady(DNSHeader &h, int length);
+ int SendRequests(const DNSHeader *header, const int length, QueryType qt);
+};
+
+class RequestTimeout : public InspTimer
+{
+ InspIRCd* ServerInstance;
+ DNSRequest* watch;
+ int watchid;
+ requestlist &rl;
+ public:
+ RequestTimeout(unsigned long n, InspIRCd* SI, DNSRequest* watching, int id, requestlist &requests) : InspTimer(n, time(NULL)), ServerInstance(SI), watch(watching), watchid(id), rl(requests)
{
- res = new unsigned char[512];
- *res = 0;
- memcpy(&myserver, &server, sizeof(insp_inaddr));
+ ServerInstance->Log(DEBUG, "New DNS timeout set on %08x", watching);
}
- /* Deallocate the processing buffer */
- ~DNSRequest()
+ void Tick(time_t TIME)
{
- delete[] res;
+ if (rl.find(watchid) != rl.end())
+ {
+ /* Still exists, whack it */
+ if (rl.find(watchid)->second == watch)
+ {
+ if (ServerInstance->Res->Classes[watchid])
+ {
+ ServerInstance->Res->Classes[watchid]->OnError(RESOLVER_TIMEOUT, "Request timed out");
+ delete ServerInstance->Res->Classes[watchid];
+ ServerInstance->Res->Classes[watchid] = NULL;
+ }
+ rl.erase(rl.find(watchid));
+ delete watch;
+ ServerInstance->Log(DEBUG, "DNS timeout on %08x squished pointer", watch);
+ }
+ return;
+ }
+ ServerInstance->Log(DEBUG, "DNS timeout on %08x: result already received!", watch);
}
-
- /* Called when a result is ready to be processed which matches this id */
- DNSInfo ResultIsReady(DNSHeader &h, int length);
-
- /* Called when there are requests to be sent out */
- int SendRequests(const DNSHeader *header, const int length, QueryType qt);
};
-/* A set of requests keyed by request id */
-typedef std::map<int,DNSRequest*> requestlist;
-
-/* An iterator into a set of requests */
-typedef requestlist::iterator requestlist_iter;
-
-/* Declare our map */
-requestlist requests;
-
-/*
- * Optimized by brain, these were using integer division and modulus.
- * We can use logic shifts and logic AND to replace these even divisions
- * and multiplications, it should be a bit faster (probably not noticably,
- * but of course, more impressive). Also made these inline.
- */
+/* Allocate the processing buffer */
+DNSRequest::DNSRequest(InspIRCd* Instance, DNS* dns, insp_inaddr server, int id, requestlist &requests) : dnsobj(dns)
+{
+ res = new unsigned char[512];
+ *res = 0;
+ memcpy(&myserver, &server, sizeof(insp_inaddr));
+ RequestTimeout* RT = new RequestTimeout(Instance->Config->dns_timeout ? Instance->Config->dns_timeout : 5, Instance, this, id, requests);
+ Instance->Timers->AddTimer(RT); /* The timer manager frees this */
+}
+/* Deallocate the processing buffer */
+DNSRequest::~DNSRequest()
+{
+ delete[] res;
+}
-/* Fill a ResourceRecord class based on raw data input */
-inline void DNSFillResourceRecord(ResourceRecord* rr, const unsigned char *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->rr_class = (input[2] << 8) + input[3];
rr->rdlength = (input[8] << 8) + input[9];
}
-/* Fill a DNSHeader class based on raw data input of a given length */
-inline void DNSFillHeader(DNSHeader *header, const unsigned char *input, const int 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];
header->id[1] = input[1];
memcpy(header->payload,&input[12],length);
}
-/* Empty a DNSHeader class out into raw data, ready for transmission */
-inline void DNSEmptyHeader(unsigned char *output, const DNSHeader *header, const int length)
+/** 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];
output[1] = header->id[1];
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;
this->rr_class = 1;
this->type = qt;
- DNSEmptyHeader(payload,header,length);
+ DNS::EmptyHeader(payload,header,length);
memset(&addr,0,sizeof(addr));
#ifdef IPV6
memcpy(&addr.sin6_addr,&myserver,sizeof(addr.sin6_addr));
addr.sin6_family = AF_FAMILY;
- addr.sin6_port = htons(53);
+ addr.sin6_port = htons(DNS::QUERY_PORT);
#else
memcpy(&addr.sin_addr.s_addr,&myserver,sizeof(addr.sin_addr));
addr.sin_family = AF_FAMILY;
- addr.sin_port = htons(53);
+ 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!");
+ 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. */
-DNSRequest* DNS::DNSAddQuery(DNSHeader *header, int &id)
+/** Add a query with a predefined header, and allocate an ID for it. */
+DNSRequest* DNS::AddQuery(DNSHeader *header, int &id)
{
- id = rand() % 65536;
- DNSRequest* req = new DNSRequest(this->myserver);
+ /* 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;
+
+ /* Create an id */
+ id = this->PRNG() & DNS::MAX_REQUEST_ID;
+
+ /* If this id is already 'in flight', pick another. */
+ while (requests.find(id) != requests.end())
+ id = this->PRNG() & DNS::MAX_REQUEST_ID;
+
+ DNSRequest* req = new DNSRequest(ServerInstance, this, this->myserver, id, requests);
header->id[0] = req->id[0] = id >> 8;
header->id[1] = req->id[1] = id & 0xFF;
header->nscount = 0;
header->arcount = 0;
- if (requests.find(id) == requests.end())
- requests[id] = req;
+ /* At this point we already know the id doesnt exist,
+ * so there needs to be no second check for the ::end()
+ */
+ requests[id] = req;
/* According to the C++ spec, new never returns NULL. */
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()
-{
- log(DEBUG,"----- Initialize dns class ----- ");
- memset(dns_classes,0,sizeof(dns_classes));
insp_inaddr addr;
- srand((unsigned int)time(NULL));
+
+ /* Clear the Resolver class table */
+ memset(Classes,0,sizeof(Classes));
+
+ /* Set the id of the next request to 0
+ */
+ currid = 0;
+
+ /* By default we're not munging ip's
+ */
+ ip6munge = false;
+
+ /* Clear the namesever address */
memset(&myserver,0,sizeof(insp_inaddr));
- if (insp_aton(Config->DNSServer,&addr) > 0)
+
+ /* Convert the nameserver address into an insp_inaddr */
+ if (insp_aton(ServerInstance->Config->DNSServer,&addr) > 0)
+ {
memcpy(&myserver,&addr,sizeof(insp_inaddr));
+ 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
+ {
+ ServerInstance->Log(DEBUG,"GACK! insp_aton says the nameserver '%s' is invalid!",ServerInstance->Config->DNSServer);
+ }
- MasterSocket = socket(PF_PROTOCOL, SOCK_DGRAM, 0);
- if (MasterSocket != -1)
+ /* Initialize mastersocket */
+ this->SetFd(socket(PF_PROTOCOL, SOCK_DGRAM, 0));
+ if (this->GetFd() != -1)
{
- log(DEBUG,"Set query socket nonblock");
- if (fcntl(MasterSocket, F_SETFL, O_NONBLOCK) != 0)
+ /* Did it succeed? */
+ if (fcntl(this->GetFd(), F_SETFL, O_NONBLOCK) != 0)
{
- shutdown(MasterSocket,2);
- close(MasterSocket);
- MasterSocket = -1;
+ /* Couldn't make the socket nonblocking */
+ shutdown(this->GetFd(),2);
+ close(this->GetFd());
+ this->SetFd(-1);
}
}
- if (MasterSocket != -1)
+ else
+ {
+ ServerInstance->Log(DEBUG,"I cant socket() this socket! (%s)",strerror(errno));
+ }
+ /* Have we got a socket and is it nonblocking? */
+ 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_port = 0;
addr.sin_addr.s_addr = INADDR_ANY;
#endif
- log(DEBUG,"Binding query port");
- if (bind(MasterSocket,(sockaddr *)&addr,sizeof(addr)) != 0)
+ /* Bind the port */
+ if (bind(this->GetFd(),(sockaddr *)&addr,sizeof(addr)) != 0)
{
- log(DEBUG,"Cant bind with source port = 0");
- shutdown(MasterSocket,2);
- close(MasterSocket);
- MasterSocket = -1;
+ /* Failed to bind */
+ ServerInstance->Log(DEBUG,"Cant bind DNS fd");
+ shutdown(this->GetFd(),2);
+ close(this->GetFd());
+ this->SetFd(-1);
}
- if (MasterSocket >= 0)
+ if (this->GetFd() >= 0)
{
- log(DEBUG,"Attach query port to socket engine");
+ 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);
+ }
+ }
}
}
}
-int DNSMakePayload(const char * const name, const unsigned short rr, const unsigned short rr_class, unsigned char * const payload)
+/** 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;
- const char * tempchr, * tempchr2;
- unsigned short l;
-
- payloadpos = 0;
- tempchr2 = name;
+ short payloadpos = 0;
+ const char* tempchr, *tempchr2 = name;
+ unsigned short length;
/* split name up into labels, create query */
while ((tempchr = strchr(tempchr2,'.')) != NULL)
{
- l = tempchr - tempchr2;
- if (payloadpos + l + 1 > 507)
+ length = tempchr - tempchr2;
+ if (payloadpos + length + 1 > 507)
return -1;
- payload[payloadpos++] = l;
- memcpy(&payload[payloadpos],tempchr2,l);
- payloadpos += l;
+ payload[payloadpos++] = length;
+ memcpy(&payload[payloadpos],tempchr2,length);
+ payloadpos += length;
tempchr2 = &tempchr[1];
}
- l = strlen(tempchr2);
- if (l)
+ length = strlen(tempchr2);
+ if (length)
{
- if (payloadpos + l + 2 > 507)
+ if (payloadpos + length + 2 > 507)
return -1;
- payload[payloadpos++] = l;
- memcpy(&payload[payloadpos],tempchr2,l);
- payloadpos += l;
- payload[payloadpos++] = '\0';
+ payload[payloadpos++] = length;
+ memcpy(&payload[payloadpos],tempchr2,length);
+ payloadpos += length;
+ payload[payloadpos++] = 0;
}
if (payloadpos > 508)
return -1;
- l = htons(rr);
- memcpy(&payload[payloadpos],&l,2);
- l = htons(rr_class);
- memcpy(&payload[payloadpos + 2],&l,2);
+ length = htons(rr);
+ memcpy(&payload[payloadpos],&length,2);
+ length = htons(rr_class);
+ memcpy(&payload[payloadpos + 2],&length,2);
return payloadpos + 4;
}
+/** Start lookup of an hostname to an IP address */
int DNS::GetIP(const char *name)
{
DNSHeader h;
int id;
int length;
- DNSRequest* req;
- if ((length = DNSMakePayload(name,DNS_QRY_A,1,(unsigned char*)&h.payload)) == -1)
+ if ((length = this->MakePayload(name, DNS_QUERY_A, 1, (unsigned char*)&h.payload)) == -1)
+ return -1;
+
+ DNSRequest* req = this->AddQuery(&h, id);
+
+ if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_A) == -1))
+ return -1;
+
+ return id;
+}
+
+/** Start lookup of an hostname to an IPv6 address */
+int DNS::GetIP6(const char *name)
+{
+ DNSHeader h;
+ int id;
+ int length;
+
+ if ((length = this->MakePayload(name, DNS_QUERY_AAAA, 1, (unsigned char*)&h.payload)) == -1)
+ return -1;
+
+ DNSRequest* req = this->AddQuery(&h, id);
+
+ if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_AAAA) == -1))
+ return -1;
+
+ return id;
+}
+
+/** Start lookup of a cname to another name */
+int DNS::GetCName(const char *alias)
+{
+ DNSHeader h;
+ int id;
+ int length;
+
+ if ((length = this->MakePayload(alias, DNS_QUERY_CNAME, 1, (unsigned char*)&h.payload)) == -1)
return -1;
- req = DNSAddQuery(&h, id);
+ DNSRequest* req = this->AddQuery(&h, id);
- if (req->SendRequests(&h,length,DNS_QRY_A) == -1)
+ if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_CNAME) == -1))
return -1;
return id;
}
+/** Start lookup of an IP address to a hostname */
int DNS::GetName(const insp_inaddr *ip)
{
-#ifdef IPV6
- return -1;
-#else
- char query[29];
+ char query[128];
DNSHeader h;
int id;
int length;
- DNSRequest* req;
+#ifdef IPV6
+ DNS::MakeIP6Int(query, (in6_addr*)ip);
+#else
unsigned char* c = (unsigned char*)&ip->s_addr;
sprintf(query,"%d.%d.%d.%d.in-addr.arpa",c[3],c[2],c[1],c[0]);
+#endif
- if ((length = DNSMakePayload(query,DNS_QRY_PTR,1,(unsigned char*)&h.payload)) == -1)
+ if ((length = this->MakePayload(query, DNS_QUERY_PTR, 1, (unsigned char*)&h.payload)) == -1)
return -1;
- req = DNSAddQuery(&h, id);
+ DNSRequest* req = this->AddQuery(&h, id);
- if (req->SendRequests(&h,length,DNS_QRY_PTR) == -1)
+ if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_PTR) == -1))
return -1;
return id;
+}
+
+/** 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;
+ if (inet_pton(AF_INET6, ip, &i) > 0)
+ {
+ DNS::MakeIP6Int(query, &i);
+ }
+ else
+ /* Invalid IP address */
+ return -1;
+ }
+ else
#endif
+ {
+ in_addr i;
+ if (inet_aton(ip, &i))
+ {
+ unsigned char* c = (unsigned char*)&i.s_addr;
+ sprintf(query,"%d.%d.%d.%d.in-addr.arpa",c[3],c[2],c[1],c[0]);
+ }
+ else
+ /* Invalid IP address */
+ return -1;
+ }
+
+ 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;
+
+ DNSRequest* req = this->AddQuery(&h, id);
+
+ if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_PTR) == -1))
+ return -1;
+
+ return id;
}
-/* Return the next id which is ready, and the result attached to it
+/** 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 */
+ {
+ if (index % 2)
+ /* low nibble */
+ *query++ = hex[ip->s6_addr[index / 2] & 0x0F];
+ else
+ /* high nibble */
+ *query++ = hex[(ip->s6_addr[index / 2] & 0xF0) >> 4];
+ *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 */
DNSResult DNS::GetResult()
{
/* Fetch dns query response and decide where it belongs */
DNSHeader header;
DNSRequest *req;
- int length;
unsigned char buffer[sizeof(DNSHeader)];
+ sockaddr from;
+ socklen_t x = sizeof(from);
+ const char* ipaddr_from = "";
+ unsigned short int port_from = 0;
+
+ int length = recvfrom(this->GetFd(),buffer,sizeof(DNSHeader),0,&from,&x);
- /* Attempt to read a header */
- length = recv(MasterSocket,buffer,sizeof(DNSHeader),0);
+ if (length < 0)
+ 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
+ * 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.
+ *
+ * -- Thanks jilles for pointing this one out.
+ */
+#ifdef IPV6
+ ipaddr_from = insp_ntoa(((sockaddr_in6*)&from)->sin6_addr);
+ port_from = ntohs(((sockaddr_in6*)&from)->sin6_port);
+#else
+ ipaddr_from = insp_ntoa(((sockaddr_in*)&from)->sin_addr);
+ port_from = ntohs(((sockaddr_in*)&from)->sin_port);
+#endif
+
+ /* 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 */
- DNSFillHeader(&header,buffer,length - 12);
+ DNS::FillHeader(&header,buffer,length - 12);
/* Get the id of this request.
* Its a 16 bit value stored in two char's,
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
}
else
{
+ char formatted[128];
+
/* Forward lookups come back as binary data. We must format them into ascii */
- if (req->type == DNS_QRY_A)
+ switch (req->type)
{
- char formatted[16];
- snprintf(formatted,16,"%u.%u.%u.%u",data.first[0],data.first[1],data.first[2],data.first[3]);
- resultstr = formatted;
- }
- else
- {
- /* Reverse lookups just come back as char* */
- resultstr = std::string((const char*)data.first);
+ case DNS_QUERY_A:
+ snprintf(formatted,16,"%u.%u.%u.%u",data.first[0],data.first[1],data.first[2],data.first[3]);
+ resultstr = formatted;
+ break;
+
+ case DNS_QUERY_AAAA:
+ {
+ snprintf(formatted,40,"%x:%x:%x:%x:%x:%x:%x:%x",
+ (ntohs(data.first[0]) + ntohs(data.first[1] << 8)),
+ (ntohs(data.first[2]) + ntohs(data.first[3] << 8)),
+ (ntohs(data.first[4]) + ntohs(data.first[5] << 8)),
+ (ntohs(data.first[6]) + ntohs(data.first[7] << 8)),
+ (ntohs(data.first[8]) + ntohs(data.first[9] << 8)),
+ (ntohs(data.first[10]) + ntohs(data.first[11] << 8)),
+ (ntohs(data.first[12]) + ntohs(data.first[13] << 8)),
+ (ntohs(data.first[14]) + ntohs(data.first[15] << 8)));
+ char* c = strstr(formatted,":0:");
+ if (c != NULL)
+ {
+ memmove(c+1,c+2,strlen(c+2) + 1);
+ c += 2;
+ while (memcmp(c,"0:",2) == 0)
+ memmove(c,c+2,strlen(c+2) + 1);
+ if (memcmp(c,"0",2) == 0)
+ *c = 0;
+ if (memcmp(formatted,"0::",3) == 0)
+ 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;
+
+ case DNS_QUERY_CNAME:
+ /* Identical handling to PTR */
+
+ case DNS_QUERY_PTR:
+ /* Reverse lookups just come back as char* */
+ resultstr = std::string((const char*)data.first);
+ break;
+
+ default:
+ 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;
+
}
/* Build the reply with the id and hostname/ip in it */
}
}
-/* A result is ready, process it */
+/** A result is ready, process it */
DNSInfo DNSRequest::ResultIsReady(DNSHeader &header, int length)
{
int i = 0;
int q = 0;
int curanswer, o;
ResourceRecord rr;
- unsigned short p;
+ unsigned short ptr;
if (!(header.flags1 & FLAGS_MASK_QR))
return std::make_pair((unsigned char*)NULL,"Not a query result");
if (length - i < 10)
return std::make_pair((unsigned char*)NULL,"Incorrectly sized DNS reply");
- DNSFillResourceRecord(&rr,&header.payload[i]);
+ DNS::FillResourceRecord(&rr,&header.payload[i]);
i += 10;
if (rr.type != this->type)
{
switch (rr.type)
{
- case DNS_QRY_PTR:
+ case DNS_QUERY_CNAME:
+ /* CNAME and PTR have the same processing code */
+ case DNS_QUERY_PTR:
o = 0;
q = 0;
while (q == 0 && i < length && o + 256 < 1023)
{
if (header.payload[i] > 63)
{
- memcpy(&p,&header.payload[i],2);
- i = ntohs(p) - 0xC000 - 12;
+ memcpy(&ptr,&header.payload[i],2);
+ i = ntohs(ptr) - 0xC000 - 12;
}
else
{
}
else
{
- res[o] = '\0';
+ res[o] = 0;
if (o != 0)
res[o++] = '.';
memcpy(&res[o],&header.payload[i + 1],header.payload[i]);
}
}
}
- res[o] = '\0';
+ res[o] = 0;
break;
- case DNS_QRY_A:
+ case DNS_QUERY_AAAA:
memcpy(res,&header.payload[i],rr.rdlength);
- res[rr.rdlength] = '\0';
- break;
+ res[rr.rdlength] = 0;
+ break;
+ case DNS_QUERY_A:
+ memcpy(res,&header.payload[i],rr.rdlength);
+ res[rr.rdlength] = 0;
+ break;
default:
memcpy(res,&header.payload[i],rr.rdlength);
- res[rr.rdlength] = '\0';
- break;
+ res[rr.rdlength] = 0;
+ break;
}
return std::make_pair(res,"No error");;
}
+/** Close the master socket */
DNS::~DNS()
{
- shutdown(MasterSocket, 2);
- close(MasterSocket);
+ shutdown(this->GetFd(), 2);
+ close(this->GetFd());
}
-Resolver::Resolver(const std::string &source, bool forward) : input(source), fwd(forward)
+/** 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)
{
- if (forward)
- {
- log(DEBUG,"Resolver: Forward lookup on %s",source.c_str());
- this->myid = ServerInstance->Res->GetIP(source.c_str());
- }
- else
+ ServerInstance->Log(DEBUG,"Instance: %08x %08x",Instance, ServerInstance);
+
+ insp_inaddr binip;
+
+ switch (querytype)
{
- log(DEBUG,"Resolver: Reverse lookup on %s",source.c_str());
- insp_inaddr binip;
- if (insp_aton(source.c_str(), &binip) > 0)
- {
- /* Valid ip address */
- this->myid = ServerInstance->Res->GetName(&binip);
- }
- else
- {
- this->OnError(RESOLVER_BADIP, "Bad IP address for reverse lookup");
- throw ModuleException("Resolver: Bad IP address");
- return;
- }
+ case DNS_QUERY_A:
+ this->myid = ServerInstance->Res->GetIP(source.c_str());
+ break;
+
+ case DNS_QUERY_PTR:
+ if (insp_aton(source.c_str(), &binip) > 0)
+ {
+ /* Valid ip address */
+ this->myid = ServerInstance->Res->GetName(&binip);
+ }
+ else
+ {
+ this->OnError(RESOLVER_BADIP, "Bad IP address for reverse lookup");
+ throw ModuleException("Resolver: Bad IP address");
+ return;
+ }
+ break;
+
+ case DNS_QUERY_PTR4:
+ querytype = DNS_QUERY_PTR;
+ this->myid = ServerInstance->Res->GetNameForce(source.c_str(), PROTOCOL_IPV4);
+ break;
+
+ case DNS_QUERY_PTR6:
+ querytype = DNS_QUERY_PTR;
+ this->myid = ServerInstance->Res->GetNameForce(source.c_str(), PROTOCOL_IPV6);
+ break;
+
+ case DNS_QUERY_AAAA:
+ this->myid = ServerInstance->Res->GetIP6(source.c_str());
+ break;
+
+ case DNS_QUERY_CNAME:
+ this->myid = ServerInstance->Res->GetCName(source.c_str());
+ break;
+
+ default:
+ this->myid = -1;
+ break;
}
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()
{
- log(DEBUG,"Resolver::~Resolver");
+ /* Nothing here (yet) either */
}
+/** Get the request id associated with this class */
int Resolver::GetId()
{
return this->myid;
}
-void DNS::MarshallReads(int fd)
+/** Process a socket read event */
+void DNS::HandleEvent(EventType et)
{
- log(DEBUG,"dns_deal_with_classes(%d)",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)
{
- DNSResult res = this->GetResult();
- if (res.first != -1)
+ /* Its an error reply */
+ if (res.first & ERROR_MASK)
{
- 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])
{
- res.first -= ERROR_MASK;
-
- log(DEBUG,"Error available, id=%d",res.first);
- if (dns_classes[res.first])
- {
- dns_classes[res.first]->OnError(RESOLVER_NXDOMAIN, res.second);
- delete dns_classes[res.first];
- dns_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])
{
- log(DEBUG,"Result available, id=%d",res.first);
- if (dns_classes[res.first])
- {
- dns_classes[res.first]->OnLookupComplete(res.second);
- delete dns_classes[res.first];
- dns_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++;
}
}
+/** Add a derived Resolver to the working set */
bool DNS::AddResolverClass(Resolver* r)
{
+ /* Check the pointers validity and the id's validity */
if ((r) && (r->GetId() > -1))
{
- if (!dns_classes[r->GetId()])
+ /* Check the slot isnt already occupied -
+ * This should NEVER happen unless we have
+ * a severely broken DNS server somewhere
+ */
+ if (!Classes[r->GetId()])
{
- dns_classes[r->GetId()] = r;
+ /* Set up the pointer to the class */
+ Classes[r->GetId()] = r;
return true;
}
else
+ /* Duplicate id */
return false;
}
else
{
- delete r;
- return true;
+ /* Pointer or id not valid.
+ * Free the item and return
+ */
+ if (r)
+ delete r;
+
+ return false;
}
}
+/** Generate pseudo-random number */
+unsigned long DNS::PRNG()
+{
+ unsigned long val = 0;
+ timeval n;
+ serverstats* s = ServerInstance->stats;
+ gettimeofday(&n,NULL);
+ val = (n.tv_usec ^ getpid() ^ geteuid() ^ (this->currid++)) ^ s->statsAccept + n.tv_sec;
+ val = val + s->statsCollisions ^ s->statsDnsGood - s->statsDnsBad;
+ val += (s->statsConnects ^ (unsigned long)s->statsSent ^ (unsigned long)s->statsRecv) - s->BoundPortCount;
+ return val;
+}
projects / user / henk / code / inspircd.git / blobdiff