/*
-dns.cpp - based on the dns library Copyright (C) 2002 Ian Gulliver
+dns.cpp - based on the firedns library Copyright (C) 2002 Ian Gulliver
This program is free software; you can redistribute it and/or modify
it under the terms of version 2 of the GNU General Public License as
#define _DNS_C
+using namespace std;
+
#include <string>
#include <stdlib.h>
#include <time.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include "dns.h"
+#include "inspircd.h"
#include "helperfuncs.h"
+#include "socketengine.h"
-extern int statsAccept,statsRefused,statsUnknown,statsCollisions,statsDns,statsDnsGood,statsDnsBad,statsConnects,statsSent,statsRecv;
+extern InspIRCd* ServerInstance;
+extern ServerConfig* Config;
#define max(a,b) (a > b ? a : b)
#define DNS_MAX 8 /* max number of nameservers used */
}
void dns_close(int fd) { /* close query */
+ log(DEBUG,"DNS: dns_close on fd %d",fd);
if (fd == lastcreate) {
wantclose = 1;
return;
}
+ shutdown(fd,2);
close(fd);
return;
}
s->fd = socket(PF_INET, SOCK_DGRAM, 0);
if (s->fd != -1) {
if (fcntl(s->fd, F_SETFL, O_NONBLOCK) != 0) {
+ shutdown(s->fd,2);
close(s->fd);
s->fd = -1;
}
addr.sin_port = 0;
addr.sin_addr.s_addr = INADDR_ANY;
if (bind(s->fd,(sockaddr *)&addr,sizeof(addr)) != 0) {
+ shutdown(s->fd,2);
close(s->fd);
s->fd = -1;
}
connection_head = s;
if (wantclose == 1) {
+ shutdown(lastcreate,2);
close(lastcreate);
wantclose = 0;
}
short payloadpos;
const char * tempchr, * tempchr2;
unsigned short l;
-
+
payloadpos = 0;
tempchr2 = name;
return dns_ntoa4_s(ip,r);
}
-char* DNS::dns_ntoa4_r(const in_addr *ip) { /* numeric to ascii (reentrant): convert 4part IP addr struct to new string */
- char *r;
- r = new char[256];
- return dns_ntoa4_s(ip,r);
-}
-
char* DNS::dns_ntoa4_s(const in_addr *ip, char *r) { /* numeric to ascii (buffered): convert 4part IP addr struct to given string */
unsigned char *m;
m = (unsigned char *)&ip->s_addr;
}
char* DNS::dns_getresult(const int cfd) { /* retrieve result of DNS query */
- static char r[RESULTSIZE];
- return dns_getresult_s(cfd,r);
-}
-
-char* DNS::dns_getresult_r(const int cfd) { /* retrieve result of DNS query (reentrant) */
- char *r;
- r = new char[RESULTSIZE];
- if(dns_getresult_s(cfd,r) == NULL) {
- delete r;
- return NULL;
- }
- return r;
+ log(DEBUG,"DNS: dns_getresult with cfd=%d",cfd);
+ return dns_getresult_s(cfd,this->localbuf);
}
char* DNS::dns_getresult_s(const int cfd, char *res) { /* retrieve result of DNS query (buffered) */
c = c->next;
}
if (c == NULL) {
+ log(DEBUG,"DNS: got a response for a query we didnt send with fd=%d",cfd);
return NULL; /* query not found */
}
/* query found-- pull from list: */
}
dns_fill_header(&h,buffer,l - 12);
if (c->id[0] != h.id[0] || c->id[1] != h.id[1]) {
+ log(DEBUG,"DNS: id mismatch on query");
delete c;
return NULL; /* ID mismatch */
}
if ((h.flags1 & FLAGS1_MASK_QR) == 0) {
+ log(DEBUG,"DNS: didnt get a query result");
delete c;
return NULL;
}
if ((h.flags1 & FLAGS1_MASK_OPCODE) != 0) {
+ log(DEBUG,"DNS: got an OPCODE and didnt want one");
delete c;
return NULL;
}
if ((h.flags2 & FLAGS2_MASK_RCODE) != 0) {
+ log(DEBUG,"DNS lookup failed due to SERVFAIL");
delete c;
return NULL;
}
if (h.ancount < 1) { /* no sense going on if we don't have any answers */
+ log(DEBUG,"DNS: no answers!");
delete c;
return NULL;
}
i = 0;
q = 0;
l -= 12;
- while (q < h.qdcount && i < l) {
+ while ((unsigned)q < h.qdcount && i < l) {
if (h.payload[i] > 63) { /* pointer */
i += 6; /* skip pointer, _class and type */
q++;
}
/* &h.payload[i] should now be the start of the first response */
curanswer = 0;
- while (curanswer < h.ancount) {
+ while ((unsigned)curanswer < h.ancount) {
q = 0;
while (q == 0 && i < l) {
if (h.payload[i] > 63) { /* pointer */
}
break;
}
- if (curanswer == h.ancount)
+ if ((unsigned)curanswer == h.ancount)
return NULL;
- if (i + rr.rdlength > l)
+ if ((unsigned)i + rr.rdlength > (unsigned)l)
return NULL;
if (rr.rdlength > 1023)
return NULL;
switch (rr.type) {
case DNS_QRY_PTR:
+ log(DEBUG,"DNS: got a result of type DNS_QRY_PTR");
o = 0;
q = 0;
while (q == 0 && i < l && o + 256 < 1023) {
res[o] = '\0';
break;
case DNS_QRY_A:
+ log(DEBUG,"DNS: got a result of type DNS_QRY_A");
if (c->want_list) {
dns_ip4list *alist = (dns_ip4list *) res; /* we have to trust that this is aligned */
while ((char *)alist - (char *)res < 700) {
return NULL;
}
memcpy(&alist->ip,&h.payload[i],4);
- if (++curanswer >= h.ancount)
+ if ((unsigned)++curanswer >= h.ancount)
break;
i += rr.rdlength;
{
break;
default:
defaultcase:
+ log(DEBUG,"DNS: doing something with result 'default'");
memcpy(res,&h.payload[i],rr.rdlength);
res[rr.rdlength] = '\0';
break;
DNS::DNS()
{
dns_init();
+ log(DEBUG,"Create blank DNS");
}
DNS::DNS(std::string dnsserver)
{
dns_init_2(dnsserver.c_str());
+ log(DEBUG,"Create DNS");
}
void DNS::SetNS(std::string dnsserver)
{
dns_init_2(dnsserver.c_str());
+ log(DEBUG,"Set NS");
}
DNS::~DNS()
bool DNS::ReverseLookup(std::string ip)
{
- statsDns++;
+ ServerInstance->stats->statsDns++;
binip = dns_aton4(ip.c_str());
if (binip == NULL) {
return false;
}
- this->fd = dns_getname4(binip);
- if (this->fd == -1)
+ this->myfd = dns_getname4(binip);
+ if (this->myfd == -1)
{
return false;
}
+ log(DEBUG,"DNS: ReverseLookup, fd=%d",this->myfd);
+#ifndef THREADED_DNS
+ ServerInstance->SE->AddFd(this->myfd,true,X_ESTAB_DNS);
+#endif
return true;
}
bool DNS::ForwardLookup(std::string host)
{
+ ServerInstance->stats->statsDns++;
+ this->myfd = dns_getip4(host.c_str());
+ if (this->myfd == -1)
+ {
+ return false;
+ }
+ log(DEBUG,"DNS: ForwardLookup, fd=%d",this->myfd);
+#ifndef THREADED_DNS
+ ServerInstance->SE->AddFd(this->myfd,true,X_ESTAB_DNS);
+#endif
+ return true;
}
+bool DNS::HasResult(int fd)
+{
+ return (fd == this->myfd);
+}
+
+/* Only the multithreaded dns uses this poll() based
+ * check now. As its in another thread we dont have
+ * to worry about its performance that much.
+ */
bool DNS::HasResult()
{
+ log(DEBUG,"DNS: HasResult, fd=%d",this->myfd);
pollfd polls;
- polls.fd = this->fd;
+ polls.fd = this->myfd;
polls.events = POLLIN;
int ret = poll(&polls,1,1);
+ log(DEBUG,"DNS: Hasresult returning %d",ret);
return (ret > 0);
}
int DNS::GetFD()
{
- return this->fd;
+ return this->myfd;
}
std::string DNS::GetResult()
{
- result = dns_getresult(this->fd);
+ log(DEBUG,"DNS: GetResult()");
+ result = dns_getresult(this->myfd);
+#ifndef THREADED_DNS
+ ServerInstance->SE->DelFd(this->myfd);
+#endif
if (result) {
- statsDnsGood++;
- dns_close(this->fd);
+ ServerInstance->stats->statsDnsGood++;
+ dns_close(this->myfd);
return result;
} else {
- statsDnsBad++;
+ ServerInstance->stats->statsDnsBad++;
+ if (this->myfd != -1)
+ {
+ dns_close(this->myfd);
+ }
+ return "";
+ }
+}
+
+std::string DNS::GetResultIP()
+{
+ char r[1024];
+ log(DEBUG,"DNS: GetResultIP()");
+ result = dns_getresult(this->myfd);
+ if (this->myfd != -1)
+ {
+#ifndef THREADED_DNS
+ ServerInstance->SE->DelFd(this->myfd);
+#endif
+ dns_close(this->myfd);
+ }
+ if (result)
+ {
+ ServerInstance->stats->statsDnsGood++;
+ unsigned char a = (unsigned)result[0];
+ unsigned char b = (unsigned)result[1];
+ unsigned char c = (unsigned)result[2];
+ unsigned char d = (unsigned)result[3];
+ snprintf(r,1024,"%u.%u.%u.%u",a,b,c,d);
+ return r;
+ }
+ else
+ {
+ ServerInstance->stats->statsDnsBad++;
+ log(DEBUG,"DANGER WILL ROBINSON! NXDOMAIN for forward lookup, but we got a reverse lookup!");
return "";
}
}
+
+
+
+#ifdef THREADED_DNS
+void* dns_task(void* arg)
+{
+ userrec* u = (userrec*)arg;
+ log(DEBUG,"DNS thread for user %s",u->nick);
+ DNS dns1;
+ DNS dns2;
+ std::string host;
+ std::string ip;
+ if (dns1.ReverseLookup(u->ip))
+ {
+ while (!dns1.HasResult())
+ {
+ usleep(100);
+ }
+ host = dns1.GetResult();
+ if (host != "")
+ {
+ if (dns2.ForwardLookup(host))
+ {
+ while (!dns2.HasResult())
+ {
+ usleep(100);
+ }
+ ip = dns2.GetResultIP();
+ if (ip == std::string(u->ip))
+ {
+ if (host.length() < 160)
+ {
+ strcpy(u->host,host.c_str());
+ strcpy(u->dhost,host.c_str());
+ }
+ }
+ }
+ }
+ }
+ u->dns_done = true;
+ return NULL;
+}
+#endif
projects / user / henk / code / inspircd.git / blobdiff