X-Git-Url: https://git.netwichtig.de/gitweb/?a=blobdiff_plain;f=src%2Fdns.cpp;h=8526d5be22bc4735db1a51c1220b49f77700403b;hb=4498f1abd163b140efcbbd9e75173665c9b1c29f;hp=f088055f87bf6b27079f1fd1ec282e34f8b24f46;hpb=a64a4665e0a2898ec08cf5996bdbf63c2567310e;p=user%2Fhenk%2Fcode%2Finspircd.git diff --git a/src/dns.cpp b/src/dns.cpp index f088055f8..8526d5be2 100644 --- a/src/dns.cpp +++ b/src/dns.cpp @@ -2,7 +2,7 @@ * | Inspire Internet Relay Chat Daemon | * +------------------------------------+ * - * InspIRCd: (C) 2002-2009 InspIRCd Development Team + * InspIRCd: (C) 2002-2010 InspIRCd Development Team * See: http://wiki.inspircd.org/Credits * * This program is free but copyrighted software; see @@ -31,10 +31,8 @@ looks like this, walks like this or tastes like this. #include #else #include "inspircd_win32wrapper.h" -#include "inspircd_se_config.h" #endif -#include "dns.h" #include "inspircd.h" #include "socketengine.h" #include "configreader.h" @@ -97,9 +95,8 @@ class DNSRequest DNS* dnsobj; /* DNS caller (where we get our FD from) */ unsigned long ttl; /* Time to live */ std::string orig; /* Original requested name/ip */ - InspIRCd* ServerInstance; - DNSRequest(InspIRCd* Instance, DNS* dns, int id, const std::string &original); + DNSRequest(DNS* dns, int id, const std::string &original); ~DNSRequest(); DNSInfo ResultIsReady(DNSHeader &h, int length); int SendRequests(const DNSHeader *header, const int length, QueryType qt); @@ -108,11 +105,10 @@ class DNSRequest class CacheTimer : public Timer { private: - InspIRCd* ServerInstance; DNS* dns; public: - CacheTimer(InspIRCd* Instance, DNS* thisdns) - : Timer(3600, Instance->Time(), true), ServerInstance(Instance), dns(thisdns) { } + CacheTimer(DNS* thisdns) + : Timer(3600, ServerInstance->Time(), true), dns(thisdns) { } virtual void Tick(time_t) { @@ -122,13 +118,17 @@ class CacheTimer : public Timer class RequestTimeout : public Timer { - InspIRCd* ServerInstance; DNSRequest* watch; int watchid; public: - RequestTimeout(unsigned long n, InspIRCd* SI, DNSRequest* watching, int id) : Timer(n, SI->Time()), ServerInstance(SI), watch(watching), watchid(id) + RequestTimeout(unsigned long n, DNSRequest* watching, int id) : Timer(n, ServerInstance->Time()), watch(watching), watchid(id) { } + ~RequestTimeout() + { + if (ServerInstance->Res) + Tick(0); + } void Tick(time_t) { @@ -143,19 +143,29 @@ class RequestTimeout : public Timer } ServerInstance->Res->requests[watchid] = NULL; delete watch; - return; } } }; +CachedQuery::CachedQuery(const std::string &res, unsigned int ttl) : data(res) +{ + expires = ServerInstance->Time() + ttl; +} + +int CachedQuery::CalcTTLRemaining() +{ + int n = expires - ServerInstance->Time(); + return (n < 0 ? 0 : n); +} + /* Allocate the processing buffer */ -DNSRequest::DNSRequest(InspIRCd* Instance, DNS* dns, int rid, const std::string &original) : dnsobj(dns), ServerInstance(Instance) +DNSRequest::DNSRequest(DNS* dns, int rid, const std::string &original) : dnsobj(dns) { res = new unsigned char[512]; *res = 0; orig = original; - RequestTimeout* RT = new RequestTimeout(Instance->Config->dns_timeout ? Instance->Config->dns_timeout : 5, Instance, this, rid); - Instance->Timers->AddTimer(RT); /* The timer manager frees this */ + RequestTimeout* RT = new RequestTimeout(ServerInstance->Config->dns_timeout ? ServerInstance->Config->dns_timeout : 5, this, rid); + ServerInstance->Timers->AddTimer(RT); /* The timer manager frees this */ } /* Deallocate the processing buffer */ @@ -217,28 +227,8 @@ int DNSRequest::SendRequests(const DNSHeader *header, const int length, QueryTyp DNS::EmptyHeader(payload,header,length); -#ifdef IPV6 - if (this->dnsobj->socketfamily == AF_INET6) - { - sockaddr_in6 addr; - memset(&addr,0,sizeof(addr)); - memcpy(&addr.sin6_addr,&dnsobj->myserver6,sizeof(addr.sin6_addr)); - addr.sin6_family = AF_INET6; - addr.sin6_port = htons(DNS::QUERY_PORT); - if (ServerInstance->SE->SendTo(dnsobj, payload, length + 12, 0, (sockaddr *) &addr, sizeof(addr)) != length+12) - return -1; - } - else -#endif - { - sockaddr_in addr; - memset(&addr,0,sizeof(addr)); - memcpy(&addr.sin_addr.s_addr,&dnsobj->myserver4,sizeof(addr.sin_addr)); - addr.sin_family = AF_INET; - addr.sin_port = htons(DNS::QUERY_PORT); - if (ServerInstance->SE->SendTo(dnsobj, (const char*)payload, length + 12, 0, (sockaddr *) &addr, sizeof(addr)) != length+12) - return -1; - } + if (ServerInstance->SE->SendTo(dnsobj, payload, length + 12, 0, &(dnsobj->myserver.sa), sa_size(dnsobj->myserver)) != length+12) + return -1; ServerInstance->Logs->Log("RESOLVER",DEBUG,"Sent OK"); return 0; @@ -252,13 +242,11 @@ DNSRequest* DNS::AddQuery(DNSHeader *header, int &id, const char* original) return NULL; /* Create an id */ - id = this->PRNG() & DNS::MAX_REQUEST_ID; - - /* If this id is already 'in flight', pick another. */ - while (requests[id]) - id = this->PRNG() & DNS::MAX_REQUEST_ID; + do { + id = ServerInstance->GenRandomInt(DNS::MAX_REQUEST_ID); + } while (requests[id]); - DNSRequest* req = new DNSRequest(ServerInstance, this, id, original); + DNSRequest* req = new DNSRequest(this, id, original); header->id[0] = req->id[0] = id >> 8; header->id[1] = req->id[1] = id & 0xFF; @@ -305,7 +293,6 @@ int DNS::PruneCache() void DNS::Rehash() { - ip6munge = false; int portpass = 0; if (this->GetFd() > -1) @@ -325,38 +312,17 @@ void DNS::Rehash() this->cache = new dnscache(); } - if ((strstr(ServerInstance->Config->DNSServer,"::ffff:") == (char*)&ServerInstance->Config->DNSServer) || (strstr(ServerInstance->Config->DNSServer,"::FFFF:") == (char*)&ServerInstance->Config->DNSServer)) - { - ServerInstance->Logs->Log("RESOLVER",DEFAULT,"WARNING: Using IPv4 addresses over IPv6 forces some DNS checks to be disabled."); - ServerInstance->Logs->Log("RESOLVER",DEFAULT," This should not cause a problem, however it is recommended you migrate"); - ServerInstance->Logs->Log("RESOLVER",DEFAULT," to a true IPv6 environment."); - this->ip6munge = true; - } - - this->socketfamily = AF_INET; -#ifdef IPV6 - if (strchr(ServerInstance->Config->DNSServer,':')) - { - this->socketfamily = AF_INET6; - inet_pton(AF_INET6, ServerInstance->Config->DNSServer, &this->myserver6); - } - else - { - inet_aton(ServerInstance->Config->DNSServer, &this->myserver4); - portpass = -1; - } -#else - inet_aton(ServerInstance->Config->DNSServer, &this->myserver4); -#endif + irc::sockets::aptosa(ServerInstance->Config->DNSServer, DNS::QUERY_PORT, myserver); /* Initialize mastersocket */ - int s = irc::sockets::OpenTCPSocket(ServerInstance->Config->DNSServer, SOCK_DGRAM); + int s = socket(myserver.sa.sa_family, SOCK_DGRAM, 0); this->SetFd(s); - ServerInstance->SE->NonBlocking(this->GetFd()); /* Have we got a socket and is it nonblocking? */ if (this->GetFd() != -1) { + ServerInstance->SE->SetReuse(s); + ServerInstance->SE->NonBlocking(s); /* Bind the port - port 0 INADDR_ANY */ if (!ServerInstance->BindSocket(this->GetFd(), portpass, "", false)) { @@ -372,7 +338,7 @@ void DNS::Rehash() /* Hook the descriptor into the socket engine */ if (ServerInstance && ServerInstance->SE) { - if (!ServerInstance->SE->AddFd(this)) + if (!ServerInstance->SE->AddFd(this, FD_WANT_POLL_READ | FD_WANT_NO_WRITE)) { ServerInstance->Logs->Log("RESOLVER",DEFAULT,"Internal error starting DNS - hostnames will NOT resolve."); ServerInstance->SE->Shutdown(this, 2); @@ -389,7 +355,7 @@ void DNS::Rehash() } /** Initialise the DNS UDP socket so that we can send requests */ -DNS::DNS(InspIRCd* Instance) : ServerInstance(Instance) +DNS::DNS() { ServerInstance->Logs->Log("RESOLVER",DEBUG,"DNS::DNS"); /* Clear the Resolver class table */ @@ -415,7 +381,7 @@ DNS::DNS(InspIRCd* Instance) : ServerInstance(Instance) */ this->Rehash(); - this->PruneTimer = new CacheTimer(ServerInstance, this); + this->PruneTimer = new CacheTimer(this); ServerInstance->Timers->AddTimer(this->PruneTimer); } @@ -511,38 +477,6 @@ int DNS::GetCName(const char *alias) return id; } -/** Start lookup of an IP address to a hostname */ -int DNS::GetName(const irc::sockets::insp_inaddr *ip) -{ - char query[128]; - DNSHeader h; - int id; - int length; - -#ifdef IPV6 - unsigned char* c = (unsigned char*)&ip->s6_addr; - if (c[0] == 0 && c[1] == 0 && c[2] == 0 && c[3] == 0 && - c[4] == 0 && c[5] == 0 && c[6] == 0 && c[7] == 0 && - c[8] == 0 && c[9] == 0 && c[10] == 0xFF && c[11] == 0xFF) - sprintf(query,"%d.%d.%d.%d.in-addr.arpa",c[15],c[14],c[13],c[12]); - else - 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 = this->MakePayload(query, DNS_QUERY_PTR, 1, (unsigned char*)&h.payload)) == -1) - return -1; - - DNSRequest* req = this->AddQuery(&h, id, irc::sockets::insp_ntoa(*ip)); - - 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) { @@ -612,9 +546,8 @@ DNSResult DNS::GetResult() DNSRequest *req; unsigned char buffer[sizeof(DNSHeader)]; irc::sockets::sockaddrs from; - socklen_t x = this->socketfamily == AF_INET ? sizeof(sockaddr_in) : sizeof(sockaddr_in6); - const char* ipaddr_from; - unsigned short int port_from = 0; + memset(&from, 0, sizeof(from)); + socklen_t x = sizeof(from); int length = ServerInstance->SE->RecvFrom(this, (char*)buffer, sizeof(DNSHeader), 0, &from.sa, &x); @@ -630,33 +563,13 @@ DNSResult DNS::GetResult() * 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. + * to the server, which is possible without this check. * * -- Thanks jilles for pointing this one out. */ -#ifdef IPV6 - char nbuf[MAXBUF]; - if (this->socketfamily == AF_INET6) - { - ipaddr_from = inet_ntop(AF_INET6, &from.in6.sin6_addr, nbuf, sizeof(nbuf)); - port_from = ntohs(from.in6.sin6_port); - } - else -#endif - { - ipaddr_from = inet_ntoa(from.in4.sin_addr); - port_from = ntohs(from.in4.sin_port); - } - - /* We cant perform this security check if you're using 4in6. - * Tough luck to you, choose one or't other! - */ - if (!ip6munge) + if (memcmp(&from, &myserver, sizeof(irc::sockets::sockaddrs))) { - if ((port_from != DNS::QUERY_PORT) || (strcasecmp(ipaddr_from, ServerInstance->Config->DNSServer))) - { - return DNSResult(-1,"",0,""); - } + return DNSResult(-1,"",0,""); } /* Put the read header info into a header class */ @@ -916,6 +829,8 @@ DNS::~DNS() ServerInstance->SE->Shutdown(this, 2); ServerInstance->SE->Close(this); ServerInstance->Timers->DelTimer(this->PruneTimer); + if (cache) + delete cache; } CachedQuery* DNS::GetCache(const std::string &source) @@ -939,7 +854,7 @@ void Resolver::TriggerCachedResult() } /** High level abstraction of dns used by application at large */ -Resolver::Resolver(InspIRCd* Instance, const std::string &source, QueryType qt, bool &cached, Module* creator) : ServerInstance(Instance), Creator(creator), input(source), querytype(qt) +Resolver::Resolver(const std::string &source, QueryType qt, bool &cached, Module* creator) : Creator(creator), input(source), querytype(qt) { ServerInstance->Logs->Log("RESOLVER",DEBUG,"Resolver::Resolver"); cached = false; @@ -959,28 +874,12 @@ Resolver::Resolver(InspIRCd* Instance, const std::string &source, QueryType qt, } } - irc::sockets::insp_inaddr binip; - switch (querytype) { case DNS_QUERY_A: this->myid = ServerInstance->Res->GetIP(source.c_str()); break; - case DNS_QUERY_PTR: - if (irc::sockets::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); @@ -1140,16 +1039,3 @@ void DNS::CleanResolvers(Module* module) } } } - -/** 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) - ServerInstance->ports.size(); - return val; -}