1 /* +------------------------------------+
2 * | Inspire Internet Relay Chat Daemon |
3 * +------------------------------------+
5 * InspIRCd is copyright (C) 2002-2006 ChatSpike-Dev.
7 * <brain@chatspike.net>
8 * <Craig@chatspike.net>
10 * Written by Craig Edwards, Craig McLure, and others.
11 * This program is free but copyrighted software; see
12 * the file COPYING for details.
14 * ---------------------------------------------------
18 dns.cpp - Nonblocking DNS functions.
19 Very very loosely based on the firedns library,
20 Copyright (C) 2002 Ian Gulliver. This file is no
21 longer anything like firedns, there are many major
22 differences between this code and the original.
23 Please do not assume that firedns works like this,
24 looks like this, walks like this or tastes like this.
31 #include <sys/types.h>
32 #include <sys/socket.h>
34 #include <sys/types.h>
35 #include <sys/socket.h>
36 #include <netinet/in.h>
37 #include <arpa/inet.h>
41 #include "helperfuncs.h"
42 #include "inspircd_config.h"
43 #include "socketengine.h"
44 #include "configreader.h"
47 extern InspIRCd* ServerInstance;
48 extern ServerConfig* Config;
50 /* Master file descriptor */
51 int DNS::MasterSocket;
53 /* Masks to mask off the responses we get from the DNSRequest methods */
56 ERROR_MASK = 0x10000 /* Result is an error */
59 /* Flags which can be ORed into a request or reply for different meanings */
62 FLAGS_MASK_RD = 0x01, /* Recursive */
64 FLAGS_MASK_AA = 0x04, /* Authoritative */
65 FLAGS_MASK_OPCODE = 0x78,
67 FLAGS_MASK_RCODE = 0x0F, /* Request */
73 /* Represents a dns resource record (rr) */
77 QueryType type; /* Record type */
78 unsigned int rr_class; /* Record class */
79 unsigned long ttl; /* Time to live */
80 unsigned int rdlength; /* Record length */
83 /* Represents a dns request/reply header, and its payload as opaque data.
88 unsigned char id[2]; /* Request id */
89 unsigned int flags1; /* Flags */
90 unsigned int flags2; /* Flags */
92 unsigned int ancount; /* Answer count */
93 unsigned int nscount; /* Nameserver count */
95 unsigned char payload[512]; /* Packet payload */
98 /* Represents a request 'on the wire' with routing information relating to
99 * where to call when we get a result
104 unsigned char id[2]; /* Request id */
105 unsigned char* res; /* Result processing buffer */
106 unsigned int rr_class; /* Request class */
107 QueryType type; /* Request type */
108 insp_inaddr myserver; /* DNS server address*/
110 /* Allocate the processing buffer */
111 DNSRequest(insp_inaddr server)
113 res = new unsigned char[512];
115 memcpy(&myserver, &server, sizeof(insp_inaddr));
118 /* Deallocate the processing buffer */
124 /* Called when a result is ready to be processed which matches this id */
125 DNSInfo ResultIsReady(DNSHeader &h, int length);
127 /* Called when there are requests to be sent out */
128 int SendRequests(const DNSHeader *header, const int length, QueryType qt);
131 /* Fill a ResourceRecord class based on raw data input */
132 inline void DNS::FillResourceRecord(ResourceRecord* rr, const unsigned char *input)
134 rr->type = (QueryType)((input[0] << 8) + input[1]);
135 rr->rr_class = (input[2] << 8) + input[3];
136 rr->ttl = (input[4] << 24) + (input[5] << 16) + (input[6] << 8) + input[7];
137 rr->rdlength = (input[8] << 8) + input[9];
140 /* Fill a DNSHeader class based on raw data input of a given length */
141 inline void DNS::FillHeader(DNSHeader *header, const unsigned char *input, const int length)
143 header->id[0] = input[0];
144 header->id[1] = input[1];
145 header->flags1 = input[2];
146 header->flags2 = input[3];
147 header->qdcount = (input[4] << 8) + input[5];
148 header->ancount = (input[6] << 8) + input[7];
149 header->nscount = (input[8] << 8) + input[9];
150 header->arcount = (input[10] << 8) + input[11];
151 memcpy(header->payload,&input[12],length);
154 /* Empty a DNSHeader class out into raw data, ready for transmission */
155 inline void DNS::EmptyHeader(unsigned char *output, const DNSHeader *header, const int length)
157 output[0] = header->id[0];
158 output[1] = header->id[1];
159 output[2] = header->flags1;
160 output[3] = header->flags2;
161 output[4] = header->qdcount >> 8;
162 output[5] = header->qdcount & 0xFF;
163 output[6] = header->ancount >> 8;
164 output[7] = header->ancount & 0xFF;
165 output[8] = header->nscount >> 8;
166 output[9] = header->nscount & 0xFF;
167 output[10] = header->arcount >> 8;
168 output[11] = header->arcount & 0xFF;
169 memcpy(&output[12],header->payload,length);
172 /* Send requests we have previously built down the UDP socket */
173 int DNSRequest::SendRequests(const DNSHeader *header, const int length, QueryType qt)
176 unsigned char payload[sizeof(DNSHeader)];
181 DNS::EmptyHeader(payload,header,length);
183 memset(&addr,0,sizeof(addr));
185 memcpy(&addr.sin6_addr,&myserver,sizeof(addr.sin6_addr));
186 addr.sin6_family = AF_FAMILY;
187 addr.sin6_port = htons(DNS::QUERY_PORT);
189 memcpy(&addr.sin_addr.s_addr,&myserver,sizeof(addr.sin_addr));
190 addr.sin_family = AF_FAMILY;
191 addr.sin_port = htons(DNS::QUERY_PORT);
193 if (sendto(DNS::GetMasterSocket(), payload, length + 12, 0, (sockaddr *) &addr, sizeof(addr)) == -1)
195 log(DEBUG,"Error in sendto! (%s)",strerror(errno));
202 /* Add a query with a predefined header, and allocate an ID for it. */
203 DNSRequest* DNS::AddQuery(DNSHeader *header, int &id)
205 /* Is the DNS connection down? */
206 if (MasterSocket == -1)
209 /* Are there already the max number of requests on the go? */
210 if (requests.size() == DNS::MAX_REQUEST_ID + 1)
214 id = this->PRNG() & DNS::MAX_REQUEST_ID;
216 /* If this id is already 'in flight', pick another. */
217 while (requests.find(id) != requests.end())
218 id = this->PRNG() & DNS::MAX_REQUEST_ID;
220 DNSRequest* req = new DNSRequest(this->myserver);
222 header->id[0] = req->id[0] = id >> 8;
223 header->id[1] = req->id[1] = id & 0xFF;
224 header->flags1 = FLAGS_MASK_RD;
231 /* At this point we already know the id doesnt exist,
232 * so there needs to be no second check for the ::end()
236 /* According to the C++ spec, new never returns NULL. */
240 int DNS::GetMasterSocket()
245 /* Initialise the DNS UDP socket so that we can send requests */
250 /* Clear the Resolver class table */
251 memset(Classes,0,sizeof(Classes));
253 /* Set the id of the next request to 0
257 /* Clear the namesever address */
258 memset(&myserver,0,sizeof(insp_inaddr));
260 /* Convert the nameserver address into an insp_inaddr */
261 if (insp_aton(Config->DNSServer,&addr) > 0)
263 memcpy(&myserver,&addr,sizeof(insp_inaddr));
264 if ((strstr(Config->DNSServer,"::ffff:") == (char*)&Config->DNSServer) || (strstr(Config->DNSServer,"::FFFF:") == (char*)&Config->DNSServer))
266 /* These dont come back looking like they did when they went in.
267 * We're forced to turn some checks off.
268 * If anyone knows how to fix this, let me know. --Brain
270 log(DEFAULT,"WARNING: Using IPv4 addresses over IPv6 forces some DNS checks to be disabled.");
271 log(DEFAULT," This should not cause a problem, however it is recommended you migrate");
272 log(DEFAULT," to a true IPv6 environment.");
273 this->ip6munge = true;
275 log(DEBUG,"Added nameserver '%s'",Config->DNSServer);
279 log(DEBUG,"GACK! insp_aton says the nameserver '%s' is invalid!",Config->DNSServer);
282 /* Initialize mastersocket */
283 MasterSocket = socket(PF_PROTOCOL, SOCK_DGRAM, 0);
284 if (MasterSocket != -1)
286 /* Did it succeed? */
287 if (fcntl(MasterSocket, F_SETFL, O_NONBLOCK) != 0)
289 /* Couldn't make the socket nonblocking */
290 shutdown(MasterSocket,2);
297 log(DEBUG,"I cant socket() this socket! (%s)",strerror(errno));
299 /* Have we got a socket and is it nonblocking? */
300 if (MasterSocket != -1)
304 memset(&addr,0,sizeof(addr));
305 addr.sin6_family = AF_FAMILY;
307 addr.sin6_addr = in6addr_any;
310 memset(&addr,0,sizeof(addr));
311 addr.sin_family = AF_FAMILY;
313 addr.sin_addr.s_addr = INADDR_ANY;
316 if (bind(MasterSocket,(sockaddr *)&addr,sizeof(addr)) != 0)
319 log(DEBUG,"Cant bind DNS::MasterSocket");
320 shutdown(MasterSocket,2);
325 if (MasterSocket >= 0)
327 log(DEBUG,"Add master socket %d",MasterSocket);
328 /* Hook the descriptor into the socket engine */
329 if (ServerInstance && ServerInstance->SE)
331 if (!ServerInstance->SE->AddFd(MasterSocket,true,X_ESTAB_DNS))
333 log(DEFAULT,"Internal error starting DNS - hostnames will NOT resolve.");
334 shutdown(MasterSocket,2);
343 /* Build a payload to be placed after the header, based upon input data, a resource type, a class and a pointer to a buffer */
344 int DNS::MakePayload(const char * const name, const QueryType rr, const unsigned short rr_class, unsigned char * const payload)
346 short payloadpos = 0;
347 const char* tempchr, *tempchr2 = name;
348 unsigned short length;
350 /* split name up into labels, create query */
351 while ((tempchr = strchr(tempchr2,'.')) != NULL)
353 length = tempchr - tempchr2;
354 if (payloadpos + length + 1 > 507)
356 payload[payloadpos++] = length;
357 memcpy(&payload[payloadpos],tempchr2,length);
358 payloadpos += length;
359 tempchr2 = &tempchr[1];
361 length = strlen(tempchr2);
364 if (payloadpos + length + 2 > 507)
366 payload[payloadpos++] = length;
367 memcpy(&payload[payloadpos],tempchr2,length);
368 payloadpos += length;
369 payload[payloadpos++] = 0;
371 if (payloadpos > 508)
374 memcpy(&payload[payloadpos],&length,2);
375 length = htons(rr_class);
376 memcpy(&payload[payloadpos + 2],&length,2);
377 return payloadpos + 4;
380 /* Start lookup of an hostname to an IP address */
381 int DNS::GetIP(const char *name)
387 if ((length = this->MakePayload(name, DNS_QUERY_A, 1, (unsigned char*)&h.payload)) == -1)
390 DNSRequest* req = this->AddQuery(&h, id);
392 if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_A) == -1))
398 /* Start lookup of an hostname to an IPv6 address */
399 int DNS::GetIP6(const char *name)
405 if ((length = this->MakePayload(name, DNS_QUERY_AAAA, 1, (unsigned char*)&h.payload)) == -1)
408 DNSRequest* req = this->AddQuery(&h, id);
410 if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_AAAA) == -1))
416 /* Start lookup of a cname to another name */
417 int DNS::GetCName(const char *alias)
423 if ((length = this->MakePayload(alias, DNS_QUERY_CNAME, 1, (unsigned char*)&h.payload)) == -1)
426 DNSRequest* req = this->AddQuery(&h, id);
428 if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_CNAME) == -1))
434 /* Start lookup of an IP address to a hostname */
435 int DNS::GetName(const insp_inaddr *ip)
443 DNS::MakeIP6Int(query, (in6_addr*)ip);
445 unsigned char* c = (unsigned char*)&ip->s_addr;
447 sprintf(query,"%d.%d.%d.%d.in-addr.arpa",c[3],c[2],c[1],c[0]);
450 if ((length = this->MakePayload(query, DNS_QUERY_PTR, 1, (unsigned char*)&h.payload)) == -1)
453 DNSRequest* req = this->AddQuery(&h, id);
455 if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_PTR) == -1))
461 /* Start lookup of an IP address to a hostname */
462 int DNS::GetNameForce(const char *ip, ForceProtocol fp)
468 #ifdef SUPPORT_IP6LINKS
469 if (fp == PROTOCOL_IPV6)
472 if (inet_pton(AF_INET6, ip, &i) > 0)
474 DNS::MakeIP6Int(query, &i);
477 /* Invalid IP address */
484 if (inet_aton(ip, &i))
486 unsigned char* c = (unsigned char*)&i.s_addr;
487 sprintf(query,"%d.%d.%d.%d.in-addr.arpa",c[3],c[2],c[1],c[0]);
490 /* Invalid IP address */
494 log(DEBUG,"DNS::GetNameForce: %s %d",query, fp);
496 if ((length = this->MakePayload(query, DNS_QUERY_PTR, 1, (unsigned char*)&h.payload)) == -1)
499 DNSRequest* req = this->AddQuery(&h, id);
501 if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_PTR) == -1))
507 void DNS::MakeIP6Int(char* query, const in6_addr *ip)
509 #ifdef SUPPORT_IP6LINKS
510 const char* hex = "0123456789abcdef";
511 for (int index = 31; index >= 0; index--) /* for() loop steps twice per byte */
515 *query++ = hex[ip->s6_addr[index / 2] & 0x0F];
518 *query++ = hex[(ip->s6_addr[index / 2] & 0xF0) >> 4];
519 *query++ = '.'; /* Seperator */
521 strcpy(query,"ip6.arpa"); /* Suffix the string */
527 /* Return the next id which is ready, and the result attached to it */
528 DNSResult DNS::GetResult()
530 /* Fetch dns query response and decide where it belongs */
533 unsigned char buffer[sizeof(DNSHeader)];
535 socklen_t x = sizeof(from);
536 const char* ipaddr_from = "";
537 unsigned short int port_from = 0;
539 int length = recvfrom(MasterSocket,buffer,sizeof(DNSHeader),0,&from,&x);
542 log(DEBUG,"Error in recvfrom()! (%s)",strerror(errno));
544 /* Did we get the whole header? */
547 /* Nope - something screwed up. */
548 log(DEBUG,"Whole header not read!");
549 return std::make_pair(-1,"");
552 /* Check wether the reply came from a different DNS
553 * server to the one we sent it to, or the source-port
555 * A user could in theory still spoof dns packets anyway
556 * but this is less trivial than just sending garbage
557 * to the client, which is possible without this check.
559 * -- Thanks jilles for pointing this one out.
562 ipaddr_from = insp_ntoa(((sockaddr_in6*)&from)->sin6_addr);
563 port_from = ntohs(((sockaddr_in6*)&from)->sin6_port);
565 ipaddr_from = insp_ntoa(((sockaddr_in*)&from)->sin_addr);
566 port_from = ntohs(((sockaddr_in*)&from)->sin_port);
569 /* We cant perform this security check if you're using 4in6.
570 * Tough luck to you, choose one or't other!
574 if ((port_from != DNS::QUERY_PORT) || (strcasecmp(ipaddr_from, Config->DNSServer)))
576 log(DEBUG,"port %d is not 53, or %s is not %s",port_from, ipaddr_from, Config->DNSServer);
577 return std::make_pair(-1,"");
581 /* Put the read header info into a header class */
582 DNS::FillHeader(&header,buffer,length - 12);
584 /* Get the id of this request.
585 * Its a 16 bit value stored in two char's,
586 * so we use logic shifts to create the value.
588 unsigned long this_id = header.id[1] + (header.id[0] << 8);
590 /* Do we have a pending request matching this id? */
591 requestlist_iter n_iter = requests.find(this_id);
592 if (n_iter == requests.end())
594 /* Somehow we got a DNS response for a request we never made... */
595 log(DEBUG,"DNS: got a response for a query we didnt send with fd=%d queryid=%d",MasterSocket,this_id);
596 return std::make_pair(-1,"");
600 /* Remove the query from the list of pending queries */
601 req = (DNSRequest*)n_iter->second;
602 requests.erase(n_iter);
605 /* Inform the DNSRequest class that it has a result to be read.
606 * When its finished it will return a DNSInfo which is a pair of
607 * unsigned char* resource record data, and an error message.
609 DNSInfo data = req->ResultIsReady(header, length);
610 std::string resultstr;
612 /* Check if we got a result, if we didnt, its an error */
613 if (data.first == NULL)
616 * Mask the ID with the value of ERROR_MASK, so that
617 * the dns_deal_with_classes() function knows that its
618 * an error response and needs to be treated uniquely.
619 * Put the error message in the second field.
622 return std::make_pair(this_id | ERROR_MASK, data.second);
628 /* Forward lookups come back as binary data. We must format them into ascii */
632 snprintf(formatted,16,"%u.%u.%u.%u",data.first[0],data.first[1],data.first[2],data.first[3]);
633 resultstr = formatted;
638 snprintf(formatted,40,"%x:%x:%x:%x:%x:%x:%x:%x",
639 (ntohs(data.first[0]) + ntohs(data.first[1] << 8)),
640 (ntohs(data.first[2]) + ntohs(data.first[3] << 8)),
641 (ntohs(data.first[4]) + ntohs(data.first[5] << 8)),
642 (ntohs(data.first[6]) + ntohs(data.first[7] << 8)),
643 (ntohs(data.first[8]) + ntohs(data.first[9] << 8)),
644 (ntohs(data.first[10]) + ntohs(data.first[11] << 8)),
645 (ntohs(data.first[12]) + ntohs(data.first[13] << 8)),
646 (ntohs(data.first[14]) + ntohs(data.first[15] << 8)));
647 char* c = strstr(formatted,":0:");
650 memmove(c+1,c+2,strlen(c+2) + 1);
652 while (memcmp(c,"0:",2) == 0)
653 memmove(c,c+2,strlen(c+2) + 1);
654 if (memcmp(c,"0",2) == 0)
656 if (memcmp(formatted,"0::",3) == 0)
657 memmove(formatted,formatted + 1, strlen(formatted + 1) + 1);
659 resultstr = formatted;
661 /* Special case. Sending ::1 around between servers
662 * and to clients is dangerous, because the : on the
663 * start makes the client or server interpret the IP
664 * as the last parameter on the line with a value ":1".
666 if (*formatted == ':')
667 resultstr = "0" + resultstr;
671 case DNS_QUERY_CNAME:
672 /* Identical handling to PTR */
675 /* Reverse lookups just come back as char* */
676 resultstr = std::string((const char*)data.first);
680 log(DEBUG,"WARNING: Somehow we made a request for a DNS_QUERY_PTR4 or DNS_QUERY_PTR6, but these arent real rr types!");
685 /* Build the reply with the id and hostname/ip in it */
687 return std::make_pair(this_id,resultstr);
691 /* A result is ready, process it */
692 DNSInfo DNSRequest::ResultIsReady(DNSHeader &header, int length)
700 if (!(header.flags1 & FLAGS_MASK_QR))
701 return std::make_pair((unsigned char*)NULL,"Not a query result");
703 if (header.flags1 & FLAGS_MASK_OPCODE)
704 return std::make_pair((unsigned char*)NULL,"Unexpected value in DNS reply packet");
706 if (header.flags2 & FLAGS_MASK_RCODE)
707 return std::make_pair((unsigned char*)NULL,"Domain name not found");
709 if (header.ancount < 1)
710 return std::make_pair((unsigned char*)NULL,"No resource records returned");
712 /* Subtract the length of the header from the length of the packet */
715 while ((unsigned int)q < header.qdcount && i < length)
717 if (header.payload[i] > 63)
724 if (header.payload[i] == 0)
729 else i += header.payload[i] + 1;
733 while ((unsigned)curanswer < header.ancount)
736 while (q == 0 && i < length)
738 if (header.payload[i] > 63)
745 if (header.payload[i] == 0)
750 else i += header.payload[i] + 1; /* skip length and label */
754 return std::make_pair((unsigned char*)NULL,"Incorrectly sized DNS reply");
756 DNS::FillResourceRecord(&rr,&header.payload[i]);
758 if (rr.type != this->type)
764 if (rr.rr_class != this->rr_class)
772 if ((unsigned int)curanswer == header.ancount)
773 return std::make_pair((unsigned char*)NULL,"No valid answers");
775 if (i + rr.rdlength > (unsigned int)length)
776 return std::make_pair((unsigned char*)NULL,"Resource record larger than stated");
778 if (rr.rdlength > 1023)
779 return std::make_pair((unsigned char*)NULL,"Resource record too large");
783 case DNS_QUERY_CNAME:
784 /* CNAME and PTR have the same processing code */
788 while (q == 0 && i < length && o + 256 < 1023)
790 if (header.payload[i] > 63)
792 memcpy(&ptr,&header.payload[i],2);
793 i = ntohs(ptr) - 0xC000 - 12;
797 if (header.payload[i] == 0)
806 memcpy(&res[o],&header.payload[i + 1],header.payload[i]);
807 o += header.payload[i];
808 i += header.payload[i] + 1;
815 memcpy(res,&header.payload[i],rr.rdlength);
816 res[rr.rdlength] = 0;
819 memcpy(res,&header.payload[i],rr.rdlength);
820 res[rr.rdlength] = 0;
823 memcpy(res,&header.payload[i],rr.rdlength);
824 res[rr.rdlength] = 0;
827 return std::make_pair(res,"No error");;
830 /* Close the master socket */
833 shutdown(MasterSocket, 2);
837 /* High level abstraction of dns used by application at large */
838 Resolver::Resolver(const std::string &source, QueryType qt) : input(source), querytype(qt)
845 this->myid = ServerInstance->Res->GetIP(source.c_str());
849 if (insp_aton(source.c_str(), &binip) > 0)
851 /* Valid ip address */
852 this->myid = ServerInstance->Res->GetName(&binip);
856 this->OnError(RESOLVER_BADIP, "Bad IP address for reverse lookup");
857 throw ModuleException("Resolver: Bad IP address");
863 querytype = DNS_QUERY_PTR;
864 this->myid = ServerInstance->Res->GetNameForce(source.c_str(), PROTOCOL_IPV4);
868 querytype = DNS_QUERY_PTR;
869 this->myid = ServerInstance->Res->GetNameForce(source.c_str(), PROTOCOL_IPV6);
873 this->myid = ServerInstance->Res->GetIP6(source.c_str());
876 case DNS_QUERY_CNAME:
877 this->myid = ServerInstance->Res->GetCName(source.c_str());
884 if (this->myid == -1)
886 log(DEBUG,"Resolver::Resolver: Could not get an id!");
887 this->OnError(RESOLVER_NSDOWN, "Nameserver is down");
888 throw ModuleException("Resolver: Couldnt get an id to make a request");
889 /* We shouldnt get here really */
893 log(DEBUG,"Resolver::Resolver: this->myid=%d",this->myid);
896 void Resolver::OnError(ResolverError e, const std::string &errormessage)
898 /* Nothing in here */
901 Resolver::~Resolver()
903 /* Nothing here (yet) either */
906 /* Get the request id associated with this class */
907 int Resolver::GetId()
912 /* Process a socket read event */
913 void DNS::MarshallReads(int fd)
915 log(DEBUG,"Marshall reads: %d %d",fd,GetMasterSocket());
916 /* We are only intrested in our single fd */
917 if (fd == GetMasterSocket())
919 /* Fetch the id and result of the next available packet */
920 DNSResult res = this->GetResult();
921 /* Is there a usable request id? */
924 /* Its an error reply */
925 if (res.first & ERROR_MASK)
927 /* Mask off the error bit */
928 res.first -= ERROR_MASK;
930 /* Marshall the error to the correct class */
931 log(DEBUG,"Error available, id=%d",res.first);
932 if (Classes[res.first])
934 if (ServerInstance && ServerInstance->stats)
935 ServerInstance->stats->statsDnsBad++;
936 Classes[res.first]->OnError(RESOLVER_NXDOMAIN, res.second);
937 delete Classes[res.first];
938 Classes[res.first] = NULL;
943 /* It is a non-error result */
944 log(DEBUG,"Result available, id=%d",res.first);
945 /* Marshall the result to the correct class */
946 if (Classes[res.first])
948 if (ServerInstance && ServerInstance->stats)
949 ServerInstance->stats->statsDnsGood++;
950 Classes[res.first]->OnLookupComplete(res.second);
951 delete Classes[res.first];
952 Classes[res.first] = NULL;
956 if (ServerInstance && ServerInstance->stats)
957 ServerInstance->stats->statsDns++;
963 /* Add a derived Resolver to the working set */
964 bool DNS::AddResolverClass(Resolver* r)
966 /* Check the pointers validity and the id's validity */
967 if ((r) && (r->GetId() > -1))
969 /* Check the slot isnt already occupied -
970 * This should NEVER happen unless we have
971 * a severely broken DNS server somewhere
973 if (!Classes[r->GetId()])
975 /* Set up the pointer to the class */
976 Classes[r->GetId()] = r;
985 /* Pointer or id not valid.
986 * Free the item and return
995 unsigned long DNS::PRNG()
997 unsigned long val = 0;
999 serverstats* s = ServerInstance->stats;
1000 gettimeofday(&n,NULL);
1001 val = (n.tv_usec ^ getpid() ^ geteuid() ^ (this->currid++)) ^ s->statsAccept + n.tv_sec;
1002 val = val + s->statsCollisions ^ s->statsDnsGood - s->statsDnsBad;
1003 val += (s->statsConnects ^ (unsigned long)s->statsSent ^ (unsigned long)s->statsRecv) - s->BoundPortCount;