-/*
-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
-published by the Free Software Foundation.
-
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-GNU General Public License for more details.
+/* +------------------------------------+
+ * | Inspire Internet Relay Chat Daemon |
+ * +------------------------------------+
+ *
+ * InspIRCd is copyright (C) 2002-2006 ChatSpike-Dev.
+ * E-mail:
+ * <brain@chatspike.net>
+ * <Craig@chatspike.net>
+ *
+ * Written by Craig Edwards, Craig McLure, and others.
+ * This program is free but copyrighted software; see
+ * the file COPYING for details.
+ *
+ * ---------------------------------------------------
+ */
-You should have received a copy of the GNU General Public License
-along with this program; if not, write to the Free Software
-Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+/*
+dns.cpp - Nonblocking DNS functions.
+Very loosely based on the firedns library,
+Copyright (C) 2002 Ian Gulliver.
+
+There have been so many modifications to this file
+to make it fit into InspIRCd and make it object
+orientated that you should not take this code as
+being what firedns really looks like. It used to
+look very different to this! :-P
*/
-#define _DNS_C
-
using namespace std;
#include <string>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <map>
+#include <algorithm>
#include "dns.h"
#include "inspircd.h"
#include "helperfuncs.h"
extern InspIRCd* ServerInstance;
extern ServerConfig* Config;
+extern time_t TIME;
-#define max(a,b) (a > b ? a : b)
-#define min(a,b) (a < b ? a : b)
-
-enum QueryTypes { DNS_QRY_A = 1, DNS_QRY_PTR = 12};
+enum QueryType { DNS_QRY_A = 1, DNS_QRY_PTR = 12 };
enum QueryFlags1 { FLAGS1_MASK_RD = 0x01, FLAGS1_MASK_TC = 0x02, FLAGS1_MASK_AA = 0x04, FLAGS1_MASK_OPCODE = 0x78, FLAGS1_MASK_QR = 0x80 };
enum QueryFlags2 { FLAGS2_MASK_RCODE = 0x0F, FLAGS2_MASK_Z = 0x70, FLAGS2_MASK_RA = 0x80 };
-#define DNS_ALIGN (sizeof(void *) > sizeof(long) ? sizeof(void *) : sizeof(long))
-#define RESULTSIZE 1024
+class s_connection;
-static struct in_addr servers4[8]; /* up to 8 nameservers; populated by dns_init() */
-static int i4; /* actual count of nameservers; set by dns_init() */
+typedef std::map<int,s_connection*> connlist;
+typedef connlist::iterator connlist_iter;
+connlist connections;
-static int initdone = 0; /* to ensure dns_init() only runs once (on the first call) */
-static int wantclose = 0;
-static int lastcreate = -1;
+struct in_addr servers4[8];
+int i4;
+int initdone = 0;
+int wantclose = 0;
+int lastcreate = -1;
class s_connection
{
public:
- unsigned char id[2];
- unsigned int _class;
- unsigned int type;
- int want_list;
- int fd; /* file descriptor returned from sockets */
+ unsigned char id[2];
+ unsigned int _class;
+ QueryType type;
+ int want_list;
+ int fd;
};
class s_rr_middle
{
public:
- unsigned int type;
- unsigned int _class;
- unsigned long ttl;
- unsigned int rdlength;
+ QueryType type;
+ unsigned int _class;
+ unsigned long ttl;
+ unsigned int rdlength;
};
-typedef std::map<int,s_connection*> connlist;
-typedef connlist::iterator connlist_iter;
-connlist connections;
-
class s_header
{
public:
- unsigned char id[2];
- unsigned int flags1;
- unsigned int flags2;
- unsigned int qdcount;
- unsigned int ancount;
- unsigned int nscount;
- unsigned int arcount;
- unsigned char payload[512]; /* DNS question, populated by dns_build_query_payload() */
+ unsigned char id[2];
+ unsigned int flags1;
+ unsigned int flags2;
+ unsigned int qdcount;
+ unsigned int ancount;
+ unsigned int nscount;
+ unsigned int arcount;
+ unsigned char payload[512];
};
-extern time_t TIME;
-void *dns_align(void *inp) {
+void *dns_align(void *inp)
+{
char *p = (char*)inp;
- int offby = ((char *)p - (char *)0) % DNS_ALIGN;
+ int offby = ((char *)p - (char *)0) % (sizeof(void *) > sizeof(long) ? sizeof(void *) : sizeof(long));
if (offby != 0)
- return p + (DNS_ALIGN - offby);
+ return p + ((sizeof(void *) > sizeof(long) ? sizeof(void *) : sizeof(long)) - offby);
else
return p;
}
* but of course, more impressive). Also made these inline.
*/
-inline void dns_fill_rr(s_rr_middle* rr, const unsigned char *input) {
- rr->type = (input[0] << 8) + input[1];
+inline void dns_fill_rr(s_rr_middle* rr, const unsigned char *input)
+{
+ rr->type = (QueryType)((input[0] << 8) + input[1]);
rr->_class = (input[2] << 8) + input[3];
rr->ttl = (input[4] << 24) + (input[5] << 16) + (input[6] << 8) + input[7];
rr->rdlength = (input[8] << 8) + input[9];
}
-inline void dns_fill_header(s_header *header, const unsigned char *input, const int l) {
+inline void dns_fill_header(s_header *header, const unsigned char *input, const int l)
+{
header->id[0] = input[0];
header->id[1] = input[1];
header->flags1 = input[2];
memcpy(header->payload,&input[12],l);
}
-inline void dns_empty_header(unsigned char *output, const s_header *header, const int l) {
+inline void dns_empty_header(unsigned char *output, const s_header *header, const int l)
+{
output[0] = header->id[0];
output[1] = header->id[1];
output[2] = header->flags1;
memcpy(&output[12],header->payload,l);
}
-void dns_close(int fd) { /* close query */
+void dns_close(int fd)
+{
#ifndef THREADED_DNS
- ServerInstance->SE->DelFd(fd);
+ if (ServerInstance && ServerInstance->SE)
+ ServerInstance->SE->DelFd(fd);
#endif
log(DEBUG,"DNS: dns_close on fd %d",fd);
- if (fd == lastcreate) {
+ if (fd == lastcreate)
+ {
wantclose = 1;
return;
}
return;
}
-void DNS::dns_init() {
+void DNS::dns_init()
+{
FILE *f;
int i;
in_addr addr4;
if (f == NULL)
return;
while (fgets(buf,1024,f) != NULL) {
- if (strncmp(buf,"nameserver",10) == 0) {
+ if (strncmp(buf,"nameserver",10) == 0)
+ {
i = 10;
while (buf[i] == ' ' || buf[i] == '\t')
i++;
- if (i4 < 8) {
+ if (i4 < 8)
+ {
if (dns_aton4_s(&buf[i],&addr4) != NULL)
memcpy(&servers4[i4++],&addr4,sizeof(in_addr));
}
}
-static int dns_send_requests(const s_header *h, const s_connection *s, const int l)
+int dns_send_requests(const s_header *h, const s_connection *s, const int l)
{
int i;
sockaddr_in addr4;
return 0;
}
-static s_connection *dns_add_query(s_header *h) { /* build DNS query, add to list */
+s_connection *dns_add_query(s_header *h)
+{
s_connection * s = new s_connection;
int id = rand() % 65536;
h->ancount = 0;
h->nscount = 0;
h->arcount = 0;
-
- /* turn off want_list by default */
s->want_list = 0;
-
- /* try to create ipv6 or ipv4 socket */
- 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;
- }
- }
- if (s->fd != -1) {
- sockaddr_in addr;
- memset(&addr,0,sizeof(addr));
- addr.sin_family = AF_INET;
- 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;
- }
+ 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;
}
- if (s->fd == -1) {
- delete s;
- return NULL;
+ }
+ if (s->fd != -1)
+ {
+ sockaddr_in addr;
+ memset(&addr,0,sizeof(addr));
+ addr.sin_family = AF_INET;
+ 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;
}
+ }
+ if (s->fd == -1)
+ {
+ delete s;
+ return NULL;
+ }
/* create new connection object, add to linked list */
if (connections.find(s->fd) == connections.end())
connections[s->fd] = s;
- if (wantclose == 1) {
+ if (wantclose == 1)
+ {
shutdown(lastcreate,2);
close(lastcreate);
wantclose = 0;
return s;
}
-static int dns_build_query_payload(const char * const name, const unsigned short rr, const unsigned short _class, unsigned char * const payload) {
+int dns_build_query_payload(const char * const name, const unsigned short rr, const unsigned short _class, unsigned char * const payload)
+{
short payloadpos;
const char * tempchr, * tempchr2;
unsigned short l;
tempchr2 = name;
/* split name up into labels, create query */
- while ((tempchr = strchr(tempchr2,'.')) != NULL) {
+ while ((tempchr = strchr(tempchr2,'.')) != NULL)
+ {
l = tempchr - tempchr2;
if (payloadpos + l + 1 > 507)
return -1;
tempchr2 = &tempchr[1];
}
l = strlen(tempchr2);
- if (l) {
+ if (l)
+ {
if (payloadpos + l + 2 > 507)
return -1;
payload[payloadpos++] = l;
return payloadpos + 4;
}
-in_addr* DNS::dns_aton4(const char * const ipstring) { /* ascii to numeric: convert string to static 4part IP addr struct */
+in_addr* DNS::dns_aton4(const char * const ipstring)
+{
static in_addr ip;
return dns_aton4_s(ipstring,&ip);
}
in_addr* DNS::dns_aton4_r(const char *ipstring) { /* ascii to numeric (reentrant): convert string to new 4part IP addr struct */
in_addr* ip;
ip = new in_addr;
- if(dns_aton4_s(ipstring,ip) == NULL) {
+ if(dns_aton4_s(ipstring,ip) == NULL)
+ {
delete ip;
return NULL;
}
dns_init();
-
l = dns_build_query_payload(name,DNS_QRY_A,1,(unsigned char *)&h.payload);
if (l == -1)
return -1;
l = recv(c->fd,buffer,sizeof(s_header),0);
dns_close(c->fd);
- if (l < 12) {
+ if (l < 12)
+ {
delete c;
return NULL;
}
dns_fill_header(&h,buffer,l - 12);
- if (c->id[0] != h.id[0] || c->id[1] != h.id[1]) {
+ 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) {
+ 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) {
+ 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) {
+ 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 */
+ if (h.ancount < 1)
+ {
log(DEBUG,"DNS: no answers!");
delete c;
return NULL;
}
- /* skip queries */
i = 0;
q = 0;
l -= 12;
- while ((unsigned)q < h.qdcount && i < l) {
- if (h.payload[i] > 63) { /* pointer */
- i += 6; /* skip pointer, _class and type */
+ while ((unsigned)q < h.qdcount && i < l)
+ {
+ if (h.payload[i] > 63)
+ {
+ i += 6;
q++;
- } else { /* label */
- if (h.payload[i] == 0) {
+ }
+ else
+ {
+ if (h.payload[i] == 0)
+ {
q++;
- i += 5; /* skip nil, _class and type */
- } else
- i += h.payload[i] + 1; /* skip length and label */
+ i += 5;
+ }
+ else i += h.payload[i] + 1;
}
}
- /* &h.payload[i] should now be the start of the first response */
curanswer = 0;
- while ((unsigned)curanswer < h.ancount) {
+ while ((unsigned)curanswer < h.ancount)
+ {
q = 0;
- while (q == 0 && i < l) {
- if (h.payload[i] > 63) { /* pointer */
- i += 2; /* skip pointer */
+ while (q == 0 && i < l)
+ {
+ if (h.payload[i] > 63)
+ {
+ i += 2;
q = 1;
- } else { /* label */
- if (h.payload[i] == 0) {
+ }
+ else
+ {
+ if (h.payload[i] == 0)
+ {
i++;
q = 1;
- } else
- i += h.payload[i] + 1; /* skip length and label */
+ }
+ else i += h.payload[i] + 1; /* skip length and label */
}
}
- if (l - i < 10) {
+ if (l - i < 10)
+ {
delete c;
return NULL;
}
dns_fill_rr(&rr,&h.payload[i]);
i += 10;
- if (rr.type != c->type) {
+ if (rr.type != c->type)
+ {
curanswer++;
i += rr.rdlength;
continue;
}
- if (rr._class != c->_class) {
+ if (rr._class != c->_class)
+ {
curanswer++;
i += rr.rdlength;
continue;
if (rr.rdlength > 1023)
return NULL;
- switch (rr.type) {
+ 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) {
- if (h.payload[i] > 63) { /* pointer */
+ while (q == 0 && i < l && o + 256 < 1023)
+ {
+ if (h.payload[i] > 63)
+ {
memcpy(&p,&h.payload[i],2);
i = ntohs(p) - 0xC000 - 12;
- } else { /* label */
+ }
+ else
+ {
if (h.payload[i] == 0)
+ {
q = 1;
- else {
+ }
+ else
+ {
res[o] = '\0';
if (o != 0)
res[o++] = '.';
}
}
res[o] = '\0';
- break;
+ break;
case DNS_QRY_A:
log(DEBUG,"DNS: got a result of type DNS_QRY_A");
- if (c->want_list) {
+ if (c->want_list)
+ {
dns_ip4list *alist = (dns_ip4list *) res; /* we have to trust that this is aligned */
- while ((char *)alist - (char *)res < 700) {
+ while ((char *)alist - (char *)res < 700)
+ {
if (rr.type != DNS_QRY_A)
break;
if (rr._class != 1)
break;
- if (rr.rdlength != 4) {
+ if (rr.rdlength != 4)
+ {
delete c;
return NULL;
}
if ((unsigned)++curanswer >= h.ancount)
break;
i += rr.rdlength;
+ q = 0;
+ while (q == 0 && i < l)
{
- /* skip next name */
- q = 0;
- while (q == 0 && i < l) {
- if (h.payload[i] > 63) { /* pointer */
- i += 2; /* skip pointer */
+ if (h.payload[i] > 63)
+ {
+ i += 2;
+ q = 1;
+ }
+ else
+ {
+ if (h.payload[i] == 0)
+ {
+ i++;
q = 1;
- } else { /* label */
- if (h.payload[i] == 0) {
- i++;
- q = 1;
- } else
- i += h.payload[i] + 1; /* skip length and label */
}
+ else i += h.payload[i] + 1;
}
}
- if (l - i < 10) {
+ if (l - i < 10)
+ {
delete c;
return NULL;
}
alist->next = NULL;
break;
}
- goto defaultcase;
+ memcpy(res,&h.payload[i],rr.rdlength);
+ res[rr.rdlength] = '\0';
break;
default:
- defaultcase:
- log(DEBUG,"DNS: doing something with result 'default'");
memcpy(res,&h.payload[i],rr.rdlength);
res[rr.rdlength] = '\0';
break;
log(DEBUG,"Create blank DNS");
}
-DNS::DNS(std::string dnsserver)
+DNS::DNS(const std::string &dnsserver)
{
dns_init_2(dnsserver.c_str());
- log(DEBUG,"Create DNS");
+ log(DEBUG,"Create DNS with server '%s'",dnsserver.c_str());
}
-void DNS::SetNS(std::string dnsserver)
+void DNS::SetNS(const std::string &dnsserver)
{
dns_init_2(dnsserver.c_str());
log(DEBUG,"Set NS");
{
}
-bool DNS::ReverseLookup(std::string ip)
+bool DNS::ReverseLookup(const std::string &ip)
{
- ServerInstance->stats->statsDns++;
+ if (ServerInstance && ServerInstance->stats)
+ ServerInstance->stats->statsDns++;
binip = dns_aton4(ip.c_str());
- if (binip == NULL) {
+ if (binip == NULL)
+ {
return false;
}
}
log(DEBUG,"DNS: ReverseLookup, fd=%d",this->myfd);
#ifndef THREADED_DNS
- ServerInstance->SE->AddFd(this->myfd,true,X_ESTAB_DNS);
+ if (ServerInstance && ServerInstance->SE)
+ ServerInstance->SE->AddFd(this->myfd,true,X_ESTAB_DNS);
#endif
return true;
}
-bool DNS::ForwardLookup(std::string host)
+bool DNS::ForwardLookup(const std::string &host)
{
- ServerInstance->stats->statsDns++;
+ if (ServerInstance && ServerInstance->stats)
+ ServerInstance->stats->statsDns++;
this->myfd = dns_getip4(host.c_str());
if (this->myfd == -1)
{
}
log(DEBUG,"DNS: ForwardLookup, fd=%d",this->myfd);
#ifndef THREADED_DNS
- ServerInstance->SE->AddFd(this->myfd,true,X_ESTAB_DNS);
+ if (ServerInstance && ServerInstance->SE)
+ ServerInstance->SE->AddFd(this->myfd,true,X_ESTAB_DNS);
#endif
return true;
}
+bool DNS::ForwardLookupWithFD(const std::string &host, int &fd)
+{
+ if (ServerInstance && ServerInstance->stats)
+ ServerInstance->stats->statsDns++;
+ this->myfd = dns_getip4(host.c_str());
+ fd = this->myfd;
+ if (this->myfd == -1)
+ {
+
+ }
+ log(DEBUG,"DNS: ForwardLookupWithFD, fd=%d",this->myfd);
+ if (ServerInstance && ServerInstance->SE)
+ ServerInstance->SE->AddFd(this->myfd,true,X_ESTAB_MODULE);
+ return true;
+}
+
bool DNS::HasResult(int fd)
{
return (fd == this->myfd);
{
log(DEBUG,"DNS: GetResult()");
result = dns_getresult(this->myfd);
- if (result) {
- ServerInstance->stats->statsDnsGood++;
+ if (result)
+ {
+ if (ServerInstance && ServerInstance->stats)
+ ServerInstance->stats->statsDnsGood++;
dns_close(this->myfd);
return result;
- } else {
- ServerInstance->stats->statsDnsBad++;
+ }
+ else
+ {
+ if (ServerInstance && ServerInstance->stats)
+ ServerInstance->stats->statsDnsBad++;
if (this->myfd != -1)
{
dns_close(this->myfd);
}
if (result)
{
- ServerInstance->stats->statsDnsGood++;
+ if (ServerInstance && ServerInstance->stats)
+ ServerInstance->stats->statsDnsGood++;
unsigned char a = (unsigned)result[0];
unsigned char b = (unsigned)result[1];
unsigned char c = (unsigned)result[2];
}
else
{
- ServerInstance->stats->statsDnsBad++;
+ if (ServerInstance && ServerInstance->stats)
+ ServerInstance->stats->statsDnsBad++;
log(DEBUG,"DANGER WILL ROBINSON! NXDOMAIN for forward lookup, but we got a reverse lookup!");
return "";
}
DNS dns2;
std::string host;
std::string ip;
- if (dns1.ReverseLookup(u->ip))
+ if (dns1.ReverseLookup((char*)inet_ntoa(u->ip4)))
{
while (!dns1.HasResult())
{
usleep(100);
}
ip = dns2.GetResultIP();
- if (ip == std::string(u->ip))
+ if (ip == std::string((char*)inet_ntoa(u->ip4)))
{
if (host.length() < 160)
{