X-Git-Url: https://git.netwichtig.de/gitweb/?a=blobdiff_plain;f=src%2Fdns.cpp;h=63b523bfda98069ef9ea957007e9eb4ffc84791f;hb=1ccbfbd4136762519f8316809b5e049453654457;hp=9788284b7fcde553718201e6d3a1861d6db7eaf5;hpb=f16930668a928471847cd327e1edc69b6d27b979;p=user%2Fhenk%2Fcode%2Finspircd.git diff --git a/src/dns.cpp b/src/dns.cpp index 9788284b7..63b523bfd 100644 --- a/src/dns.cpp +++ b/src/dns.cpp @@ -2,18 +2,17 @@ * | Inspire Internet Relay Chat Daemon | * +------------------------------------+ * - * InspIRCd is copyright (C) 2002-2006 ChatSpike-Dev. - * E-mail: - * - * - * - * Written by Craig Edwards, Craig McLure, and others. + * InspIRCd: (C) 2002-2008 InspIRCd Development Team + * See: http://www.inspircd.org/wiki/index.php/Credits + * * This program is free but copyrighted software; see - * the file COPYING for details. + * the file COPYING for details. * * --------------------------------------------------- */ +/* $Core */ + /* dns.cpp - Nonblocking DNS functions. Very very loosely based on the firedns library, @@ -24,39 +23,32 @@ Please do not assume that firedns works like this, looks like this, walks like this or tastes like this. */ -using namespace std; - -#include -#include +#ifndef WIN32 #include #include #include -#include -#include #include #include -#include +#else +#include "inspircd_win32wrapper.h" +#include "inspircd_se_config.h" +#endif + #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; - -/* 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 */ @@ -70,17 +62,17 @@ enum QueryFlags }; -/* Represents a dns resource record (rr) */ -class ResourceRecord +/** Represents a dns resource record (rr) + */ +struct ResourceRecord { - public: QueryType type; /* Record type */ unsigned int rr_class; /* Record class */ unsigned long ttl; /* Time to live */ 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 { @@ -95,40 +87,84 @@ 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 */ + 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) */ + 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(); + DNSInfo ResultIsReady(DNSHeader &h, int length, int result_we_want); + int SendRequests(const DNSHeader *header, const int length, QueryType qt); +}; + +class CacheTimer : public Timer +{ + private: + InspIRCd* ServerInstance; + DNS* dns; + public: + CacheTimer(InspIRCd* Instance, DNS* thisdns) + : Timer(3600, Instance->Time(), true), ServerInstance(Instance), dns(thisdns) { } - /* Allocate the processing buffer */ - DNSRequest(insp_inaddr server) + virtual void Tick(time_t) { - res = new unsigned char[512]; - *res = 0; - memcpy(&myserver, &server, sizeof(insp_inaddr)); + dns->PruneCache(); } +}; - /* Deallocate the processing buffer */ - ~DNSRequest() +class RequestTimeout : public Timer +{ + InspIRCd* ServerInstance; + DNSRequest* watch; + int watchid; + public: + RequestTimeout(unsigned long n, InspIRCd* SI, DNSRequest* watching, int id) : Timer(n, time(NULL)), ServerInstance(SI), watch(watching), watchid(id) { - delete[] res; } - /* 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); + void Tick(time_t) + { + if (ServerInstance->Res->requests[watchid] == watch) + { + /* Still exists, whack it */ + 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; + } + ServerInstance->Res->requests[watchid] = NULL; + delete watch; + return; + } + } }; -/* Fill a ResourceRecord class based on raw data input */ +/* Allocate the processing buffer */ +DNSRequest::DNSRequest(InspIRCd* Instance, DNS* dns, int rid, const std::string &original) : dnsobj(dns), ServerInstance(Instance) +{ + 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 */ +} + +/* Deallocate the processing buffer */ +DNSRequest::~DNSRequest() +{ + delete[] res; +} + +/** 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]); @@ -137,7 +173,7 @@ inline void DNS::FillResourceRecord(ResourceRecord* rr, const unsigned char *inp rr->rdlength = (input[8] << 8) + input[9]; } -/* Fill a DNSHeader class based on raw data input of a given 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]; @@ -151,7 +187,7 @@ inline void DNS::FillHeader(DNSHeader *header, const unsigned char *input, const memcpy(header->payload,&input[12],length); } -/* Empty a DNSHeader class out into raw data, ready for transmission */ +/** 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]; @@ -169,10 +205,11 @@ inline void DNS::EmptyHeader(unsigned char *output, const DNSHeader *header, con 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; + ServerInstance->Logs->Log("RESOLVER", DEBUG,"DNSRequest::SendRequests"); + unsigned char payload[sizeof(DNSHeader)]; this->rr_class = 1; @@ -180,40 +217,48 @@ int DNSRequest::SendRequests(const DNSHeader *header, const int length, QueryTyp 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(DNS::QUERY_PORT); -#else - memcpy(&addr.sin_addr.s_addr,&myserver,sizeof(addr.sin_addr)); - addr.sin_family = AF_FAMILY; - addr.sin_port = htons(DNS::QUERY_PORT); + 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 - if (sendto(DNS::GetMasterSocket(), payload, length + 12, 0, (sockaddr *) &addr, sizeof(addr)) == -1) { - log(DEBUG,"Error in sendto!"); - return -1; + 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; } + ServerInstance->Logs->Log("RESOLVER",DEBUG,"Sent OK"); return 0; } -/* Add a query with a predefined header, and allocate an ID for it. */ -DNSRequest* DNS::AddQuery(DNSHeader *header, int &id) +/** Add a query with a predefined header, and allocate an ID for it. */ +DNSRequest* DNS::AddQuery(DNSHeader *header, int &id, const char* original) { - /* Are there already the max number of requests on the go? */ - if (requests.size() == DNS::MAX_REQUEST_ID + 1) + /* Is the DNS connection down? */ + if (this->GetFd() == -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()) + while (requests[id]) id = this->PRNG() & DNS::MAX_REQUEST_ID; - DNSRequest* req = new DNSRequest(this->myserver); + DNSRequest* req = new DNSRequest(ServerInstance, this, id, original); header->id[0] = req->id[0] = id >> 8; header->id[1] = req->id[1] = id & 0xFF; @@ -233,79 +278,149 @@ DNSRequest* DNS::AddQuery(DNSHeader *header, int &id) return req; } -int DNS::GetMasterSocket() +int DNS::ClearCache() { - return MasterSocket; + /* This ensures the buckets are reset to sane levels */ + int rv = this->cache->size(); + delete this->cache; + this->cache = new dnscache(); + return rv; } -/* Initialise the DNS UDP socket so that we can send requests */ -DNS::DNS() +int DNS::PruneCache() { - insp_inaddr addr; + int n = 0; + dnscache* newcache = new dnscache(); + for (dnscache::iterator i = this->cache->begin(); i != this->cache->end(); i++) + /* Dont include expired items (theres no point) */ + if (i->second.CalcTTLRemaining()) + newcache->insert(*i); + else + n++; - /* Clear the Resolver class table */ - memset(Classes,0,sizeof(Classes)); + delete this->cache; + this->cache = newcache; + return n; +} - /* Set the id of the next request to 0 - */ - currid = 0; +void DNS::Rehash() +{ + ip6munge = false; + int portpass = 0; - /* Clear the namesever address */ - memset(&myserver,0,sizeof(insp_inaddr)); + if (this->GetFd() > -1) + { + if (ServerInstance && ServerInstance->SE) + ServerInstance->SE->DelFd(this); + ServerInstance->SE->Shutdown(this, 2); + ServerInstance->SE->Close(this); + this->SetFd(-1); + + /* Rehash the cache */ + this->PruneCache(); + } + else + { + /* Create initial dns cache */ + this->cache = new dnscache(); + } - /* Convert the nameserver address into an insp_inaddr */ - if (insp_aton(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)) + { + 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; + } - /* Initialize mastersocket */ - MasterSocket = socket(PF_PROTOCOL, SOCK_DGRAM, 0); - if (MasterSocket != -1) + this->socketfamily = AF_INET; +#ifdef IPV6 + if (strchr(ServerInstance->Config->DNSServer,':')) { - /* Did it succeed? */ - if (fcntl(MasterSocket, F_SETFL, O_NONBLOCK) != 0) - { - /* Couldn't make the socket nonblocking */ - shutdown(MasterSocket,2); - close(MasterSocket); - MasterSocket = -1; - } + this->socketfamily = AF_INET6; + inet_pton(AF_INET6, ServerInstance->Config->DNSServer, &this->myserver6); } - /* Have we got a socket and is it nonblocking? */ - if (MasterSocket != -1) + else { -#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)); + inet_aton(ServerInstance->Config->DNSServer, &this->myserver4); + portpass = -1; + } #else - insp_sockaddr addr; - memset(&addr,0,sizeof(addr)); - addr.sin_family = AF_FAMILY; - addr.sin_port = 0; - addr.sin_addr.s_addr = INADDR_ANY; + inet_aton(ServerInstance->Config->DNSServer, &this->myserver4); #endif - /* Bind the port */ - if (bind(MasterSocket,(sockaddr *)&addr,sizeof(addr)) != 0) + + /* Initialize mastersocket */ + int s = irc::sockets::OpenTCPSocket(ServerInstance->Config->DNSServer, SOCK_DGRAM); + this->SetFd(s); + ServerInstance->SE->NonBlocking(this->GetFd()); + + /* Have we got a socket and is it nonblocking? */ + if (this->GetFd() != -1) + { + /* Bind the port - port 0 INADDR_ANY */ + if (!ServerInstance->BindSocket(this->GetFd(), portpass, "", false)) { /* Failed to bind */ - log(DEBUG,"Cant bind DNS::MasterSocket"); - shutdown(MasterSocket,2); - close(MasterSocket); - MasterSocket = -1; + ServerInstance->Logs->Log("RESOLVER",DEBUG,"Error binding dns socket"); + ServerInstance->SE->Shutdown(this, 2); + ServerInstance->SE->Close(this); + this->SetFd(-1); } - if (MasterSocket >= 0) + if (this->GetFd() >= 0) { /* 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->Logs->Log("RESOLVER",DEFAULT,"Internal error starting DNS - hostnames will NOT resolve."); + ServerInstance->SE->Shutdown(this, 2); + ServerInstance->SE->Close(this); + this->SetFd(-1); + } + } } } + else + { + ServerInstance->Logs->Log("RESOLVER",DEBUG,"Error creating dns socket"); + } } -/* Build a payload to be placed after the header, based upon input data, a resource type, a class and a pointer to a buffer */ +/** Initialise the DNS UDP socket so that we can send requests */ +DNS::DNS(InspIRCd* Instance) : ServerInstance(Instance) +{ + ServerInstance->Logs->Log("RESOLVER",DEBUG,"DNS::DNS"); + /* Clear the Resolver class table */ + memset(Classes,0,sizeof(Classes)); + + /* Clear the requests class table */ + memset(requests,0,sizeof(requests)); + + /* Set the id of the next request to 0 + */ + currid = 0; + + /* DNS::Rehash() sets this to a valid ptr + */ + this->cache = NULL; + + /* Again, DNS::Rehash() sets this to a + * valid value + */ + this->SetFd(-1); + + /* Actually read the settings + */ + this->Rehash(); + + this->PruneTimer = new CacheTimer(ServerInstance, this); + + ServerInstance->Timers->AddTimer(this->PruneTimer); +} + +/** 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 = 0; @@ -342,7 +457,7 @@ int DNS::MakePayload(const char * const name, const QueryType rr, const unsigned return payloadpos + 4; } -/* Start lookup of an hostname to an IP address */ +/** Start lookup of an hostname to an IP address */ int DNS::GetIP(const char *name) { DNSHeader h; @@ -352,7 +467,7 @@ int DNS::GetIP(const char *name) if ((length = this->MakePayload(name, DNS_QUERY_A, 1, (unsigned char*)&h.payload)) == -1) return -1; - DNSRequest* req = this->AddQuery(&h, id); + DNSRequest* req = this->AddQuery(&h, id, name); if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_A) == -1)) return -1; @@ -360,7 +475,7 @@ int DNS::GetIP(const char *name) return id; } -/* Start lookup of an hostname to an IPv6 address */ +/** Start lookup of an hostname to an IPv6 address */ int DNS::GetIP6(const char *name) { DNSHeader h; @@ -370,7 +485,7 @@ int DNS::GetIP6(const char *name) if ((length = this->MakePayload(name, DNS_QUERY_AAAA, 1, (unsigned char*)&h.payload)) == -1) return -1; - DNSRequest* req = this->AddQuery(&h, id); + DNSRequest* req = this->AddQuery(&h, id, name); if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_AAAA) == -1)) return -1; @@ -378,7 +493,7 @@ int DNS::GetIP6(const char *name) return id; } -/* Start lookup of a cname to another name */ +/** Start lookup of a cname to another name */ int DNS::GetCName(const char *alias) { DNSHeader h; @@ -388,7 +503,7 @@ int DNS::GetCName(const char *alias) if ((length = this->MakePayload(alias, DNS_QUERY_CNAME, 1, (unsigned char*)&h.payload)) == -1) return -1; - DNSRequest* req = this->AddQuery(&h, id); + DNSRequest* req = this->AddQuery(&h, id, alias); if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_CNAME) == -1)) return -1; @@ -396,8 +511,8 @@ int DNS::GetCName(const char *alias) return id; } -/* Start lookup of an IP address to a hostname */ -int DNS::GetName(const insp_inaddr *ip) +/** Start lookup of an IP address to a hostname */ +int DNS::GetName(const irc::sockets::insp_inaddr *ip) { char query[128]; DNSHeader h; @@ -405,17 +520,22 @@ int DNS::GetName(const insp_inaddr *ip) int length; #ifdef IPV6 - DNS::MakeIP6Int(query, (in6_addr*)ip); + 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); + DNSRequest* req = this->AddQuery(&h, id, irc::sockets::insp_ntoa(*ip)); if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_PTR) == -1)) return -1; @@ -423,62 +543,97 @@ int DNS::GetName(const insp_inaddr *ip) 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; + } + + if ((length = this->MakePayload(query, DNS_QUERY_PTR, 1, (unsigned char*)&h.payload)) == -1) + return -1; + + DNSRequest* req = this->AddQuery(&h, id, ip); + + if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_PTR) == -1)) + return -1; + + return id; +} + +/** Build an ipv6 reverse domain from an in6_addr + */ void DNS::MakeIP6Int(char* query, const in6_addr *ip) { - sprintf(query,"%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.%0x.ip6.int", - ip->s6_addr[15] & 0x0f, - (ip->s6_addr[15] & 0xf0) >> 4, - ip->s6_addr[14] & 0x0f, - (ip->s6_addr[14] & 0xf0) >> 4, - ip->s6_addr[13] & 0x0f, - (ip->s6_addr[13] & 0xf0) >> 4, - ip->s6_addr[12] & 0x0f, - (ip->s6_addr[12] & 0xf0) >> 4, - ip->s6_addr[11] & 0x0f, - (ip->s6_addr[11] & 0xf0) >> 4, - ip->s6_addr[10] & 0x0f, - (ip->s6_addr[10] & 0xf0) >> 4, - ip->s6_addr[9] & 0x0f, - (ip->s6_addr[9] & 0xf0) >> 4, - ip->s6_addr[8] & 0x0f, - (ip->s6_addr[8] & 0xf0) >> 4, - ip->s6_addr[7] & 0x0f, - (ip->s6_addr[7] & 0xf0) >> 4, - ip->s6_addr[6] & 0x0f, - (ip->s6_addr[6] & 0xf0) >> 4, - ip->s6_addr[5] & 0x0f, - (ip->s6_addr[5] & 0xf0) >> 4, - ip->s6_addr[4] & 0x0f, - (ip->s6_addr[4] & 0xf0) >> 4, - ip->s6_addr[3] & 0x0f, - (ip->s6_addr[3] & 0xf0) >> 4, - ip->s6_addr[2] & 0x0f, - (ip->s6_addr[2] & 0xf0) >> 4, - ip->s6_addr[1] & 0x0f, - (ip->s6_addr[1] & 0xf0) >> 4, - ip->s6_addr[0] & 0x0f, - (ip->s6_addr[0] & 0xf0) >> 4 - ); -} - -/* Return the next id which is ready, and the result attached to it */ -DNSResult DNS::GetResult() +#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(int resultnum) { /* Fetch dns query response and decide where it belongs */ DNSHeader header; DNSRequest *req; unsigned char buffer[sizeof(DNSHeader)]; - sockaddr from; - socklen_t x = sizeof(from); - const char* ipaddr_from = ""; + sockaddr* from = new sockaddr[2]; +#ifdef IPV6 + socklen_t x = this->socketfamily == AF_INET ? sizeof(sockaddr_in) : sizeof(sockaddr_in6); +#else + socklen_t x = sizeof(sockaddr_in); +#endif + const char* ipaddr_from; unsigned short int port_from = 0; - int length = recvfrom(MasterSocket,buffer,sizeof(DNSHeader),0,&from,&x); + int length = ServerInstance->SE->RecvFrom(this, (char*)buffer, sizeof(DNSHeader), 0, from, &x); /* Did we get the whole header? */ if (length < 12) + { /* Nope - something screwed up. */ - return std::make_pair(-1,""); + delete[] from; + return DNSResult(-1,"",0,""); + } /* Check wether the reply came from a different DNS * server to the one we sent it to, or the source-port @@ -490,15 +645,31 @@ DNSResult DNS::GetResult() * -- 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); + char nbuf[MAXBUF]; + if (this->socketfamily == AF_INET6) + { + ipaddr_from = inet_ntop(AF_INET6, &((sockaddr_in6*)from)->sin6_addr, nbuf, sizeof(nbuf)); + port_from = ntohs(((sockaddr_in6*)from)->sin6_port); + } + else #endif + { + ipaddr_from = inet_ntoa(((sockaddr_in*)from)->sin_addr); + port_from = ntohs(((sockaddr_in*)from)->sin_port); + } - if ((port_from != DNS::QUERY_PORT) || (strcasecmp(ipaddr_from, Config->DNSServer))) - return std::make_pair(-1,""); + delete[] from; + + /* 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))) + { + return DNSResult(-1,"",0,""); + } + } /* Put the read header info into a header class */ DNS::FillHeader(&header,buffer,length - 12); @@ -510,25 +681,23 @@ DNSResult DNS::GetResult() unsigned long this_id = header.id[1] + (header.id[0] << 8); /* Do we have a pending request matching this id? */ - requestlist_iter n_iter = requests.find(this_id); - if (n_iter == requests.end()) + if (!requests[this_id]) { /* 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); - return std::make_pair(-1,""); + return DNSResult(-1,"",0,""); } else { /* Remove the query from the list of pending queries */ - req = (DNSRequest*)n_iter->second; - requests.erase(n_iter); + req = requests[this_id]; + requests[this_id] = NULL; } /* Inform the DNSRequest class that it has a result to be read. * When its finished it will return a DNSInfo which is a pair of * unsigned char* resource record data, and an error message. */ - DNSInfo data = req->ResultIsReady(header, length); + DNSInfo data = req->ResultIsReady(header, length, resultnum); std::string resultstr; /* Check if we got a result, if we didnt, its an error */ @@ -540,11 +709,13 @@ DNSResult DNS::GetResult() * an error response and needs to be treated uniquely. * Put the error message in the second field. */ + std::string ro = req->orig; delete req; - return std::make_pair(this_id | ERROR_MASK, data.second); + return DNSResult(this_id | ERROR_MASK, data.second, 0, ro); } else { + unsigned long ttl = req->ttl; char formatted[128]; /* Forward lookups come back as binary data. We must format them into ascii */ @@ -557,15 +728,7 @@ DNSResult DNS::GetResult() 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))); + inet_ntop(AF_INET6, data.first, formatted, sizeof(formatted)); char* c = strstr(formatted,":0:"); if (c != NULL) { @@ -579,6 +742,14 @@ DNSResult DNS::GetResult() 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.insert(0, "0"); } break; @@ -589,24 +760,34 @@ DNSResult DNS::GetResult() /* Reverse lookups just come back as char* */ resultstr = std::string((const char*)data.first); break; + + default: + break; } /* Build the reply with the id and hostname/ip in it */ + std::string ro = req->orig; delete req; - return std::make_pair(this_id,resultstr); + return DNSResult(this_id,resultstr,ttl,ro); } } -/* A result is ready, process it */ -DNSInfo DNSRequest::ResultIsReady(DNSHeader &header, int length) +/** A result is ready, process it */ +DNSInfo DNSRequest::ResultIsReady(DNSHeader &header, int length, int result_we_want) { int i = 0; int q = 0; int curanswer, o; ResourceRecord rr; unsigned short ptr; - + + /* This is just to keep _FORTIFY_SOURCE happy */ + rr.type = DNS_QUERY_NONE; + rr.rdlength = 0; + rr.ttl = 1; /* GCC is a whiney bastard -- see the XXX below. */ + rr.rr_class = 0; /* Same for VC++ */ + if (!(header.flags1 & FLAGS_MASK_QR)) return std::make_pair((unsigned char*)NULL,"Not a query result"); @@ -663,7 +844,10 @@ DNSInfo DNSRequest::ResultIsReady(DNSHeader &header, int length) if (length - i < 10) return std::make_pair((unsigned char*)NULL,"Incorrectly sized DNS reply"); - DNS::FillResourceRecord(&rr,&header.payload[i]); + /* XXX: We actually initialise 'rr' here including its ttl field */ + if (curanswer == result_we_want) + DNS::FillResourceRecord(&rr,&header.payload[i]); + i += 10; if (rr.type != this->type) { @@ -680,7 +864,7 @@ DNSInfo DNSRequest::ResultIsReady(DNSHeader &header, int length) break; } if ((unsigned int)curanswer == header.ancount) - return std::make_pair((unsigned char*)NULL,"No valid answers"); + return std::make_pair((unsigned char*)NULL,"No more answers (" + ConvToStr(header.ancount) + " answers, wanted #" + ConvToStr(result_we_want) + ")"); if (i + rr.rdlength > (unsigned int)length) return std::make_pair((unsigned char*)NULL,"Resource record larger than stated"); @@ -688,6 +872,8 @@ DNSInfo DNSRequest::ResultIsReady(DNSHeader &header, int length) if (rr.rdlength > 1023) return std::make_pair((unsigned char*)NULL,"Resource record too large"); + this->ttl = rr.ttl; + switch (rr.type) { case DNS_QUERY_CNAME: @@ -734,20 +920,59 @@ DNSInfo DNSRequest::ResultIsReady(DNSHeader &header, int length) res[rr.rdlength] = 0; break; } - return std::make_pair(res,"No error");; + return std::make_pair(res,"No error"); } -/* Close the master socket */ +/** Close the master socket */ DNS::~DNS() { - shutdown(MasterSocket, 2); - close(MasterSocket); + ServerInstance->SE->Shutdown(this, 2); + ServerInstance->SE->Close(this); + ServerInstance->Timers->DelTimer(this->PruneTimer); +} + +CachedQuery* DNS::GetCache(const std::string &source) +{ + dnscache::iterator x = cache->find(source.c_str()); + if (x != cache->end()) + return &(x->second); + else + return NULL; +} + +void DNS::DelCache(const std::string &source) +{ + cache->erase(source.c_str()); } -/* High level abstraction of dns used by application at large */ -Resolver::Resolver(const std::string &source, QueryType qt) : input(source), querytype(qt) +void Resolver::TriggerCachedResult() { - insp_inaddr binip; + if (CQ) + OnLookupComplete(CQ->data, time_left, true, 0); +} + +/** 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) +{ + ServerInstance->Logs->Log("RESOLVER",DEBUG,"Resolver::Resolver"); + cached = false; + + CQ = ServerInstance->Res->GetCache(source); + if (CQ) + { + time_left = CQ->CalcTTLRemaining(); + if (!time_left) + { + ServerInstance->Res->DelCache(source); + } + else + { + cached = true; + return; + } + } + + irc::sockets::insp_inaddr binip; switch (querytype) { @@ -756,7 +981,7 @@ Resolver::Resolver(const std::string &source, QueryType qt) : input(source), que break; case DNS_QUERY_PTR: - if (insp_aton(source.c_str(), &binip) > 0) + if (irc::sockets::insp_aton(source.c_str(), &binip) > 0) { /* Valid ip address */ this->myid = ServerInstance->Res->GetName(&binip); @@ -769,6 +994,16 @@ Resolver::Resolver(const std::string &source, QueryType qt) : input(source), que } 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; @@ -783,85 +1018,100 @@ Resolver::Resolver(const std::string &source, QueryType qt) : input(source), que } if (this->myid == -1) { - 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); + else + { + ServerInstance->Logs->Log("RESOLVER",DEBUG,"DNS request id %d", this->myid); + } } -void Resolver::OnError(ResolverError e, const std::string &errormessage) +/** Called when an error occurs */ +void Resolver::OnError(ResolverError, const std::string&) { /* Nothing in here */ } +/** Destroy a resolver */ Resolver::~Resolver() { /* Nothing here (yet) either */ } -/* Get the request id associated with this class */ +/** Get the request id associated with this class */ int Resolver::GetId() { return this->myid; } -/* Process a socket read event */ -void DNS::MarshallReads(int fd) +Module* Resolver::GetCreator() { - /* We are only intrested in our single fd */ - if (fd == GetMasterSocket()) + return this->Creator; +} + +/** Process a socket read event */ +void DNS::HandleEvent(EventType, int) +{ + /* Fetch the id and result of the next available packet */ + int resultnum = 0; + DNSResult res(0,"",0,""); + res.id = 0; + ServerInstance->Logs->Log("RESOLVER",DEBUG,"Handle DNS event"); + + res = this->GetResult(resultnum); + + ServerInstance->Logs->Log("RESOLVER",DEBUG,"Result %d id %d", resultnum, res.id); + + /* Is there a usable request id? */ + if (res.id != -1) { - /* Fetch the id and result of the next available packet */ - DNSResult res = this->GetResult(); - /* Is there a usable request id? */ - if (res.first != -1) + /* Its an error reply */ + if (res.id & ERROR_MASK) { - /* Its an error reply */ - if (res.first & ERROR_MASK) + /* Mask off the error bit */ + res.id -= ERROR_MASK; + /* Marshall the error to the correct class */ + if (Classes[res.id]) { - /* Mask off the error bit */ - res.first -= ERROR_MASK; - - /* Marshall the error to the correct class */ - log(DEBUG,"Error available, id=%d",res.first); - if (Classes[res.first]) - { - if (ServerInstance && ServerInstance->stats) - ServerInstance->stats->statsDnsBad++; - Classes[res.first]->OnError(RESOLVER_NXDOMAIN, res.second); - delete Classes[res.first]; - Classes[res.first] = NULL; - } + if (ServerInstance && ServerInstance->stats) + ServerInstance->stats->statsDnsBad++; + Classes[res.id]->OnError(RESOLVER_NXDOMAIN, res.result); + delete Classes[res.id]; + Classes[res.id] = NULL; } - else + return; + } + else + { + /* It is a non-error result, marshall the result to the correct class */ + if (Classes[res.id]) { - /* It is a non-error result */ - log(DEBUG,"Result available, id=%d",res.first); - /* Marshall the result to the correct class */ - if (Classes[res.first]) - { - 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++; + if (ServerInstance && ServerInstance->stats) + ServerInstance->stats->statsDnsGood++; + + if (!this->GetCache(res.original.c_str())) + this->cache->insert(std::make_pair(res.original.c_str(), CachedQuery(res.result, res.ttl))); + Classes[res.id]->OnLookupComplete(res.result, res.ttl, false, resultnum); + delete Classes[res.id]; + Classes[res.id] = NULL; + } } + + if (ServerInstance && ServerInstance->stats) + ServerInstance->stats->statsDns++; } -} -/* Add a derived Resolver to the working set */ + resultnum++; +} + +/** Add a derived Resolver to the working set */ bool DNS::AddResolverClass(Resolver* r) { + ServerInstance->Logs->Log("RESOLVER",DEBUG,"AddResolverClass 0x%08lx", (unsigned long)r); /* Check the pointers validity and the id's validity */ if ((r) && (r->GetId() > -1)) { @@ -891,15 +1141,33 @@ bool DNS::AddResolverClass(Resolver* r) } } +void DNS::CleanResolvers(Module* module) +{ + for (int i = 0; i < MAX_REQUEST_ID; i++) + { + if (Classes[i]) + { + if (Classes[i]->GetCreator() == module) + { + Classes[i]->OnError(RESLOVER_FORCEUNLOAD, "Parent module is unloading"); + delete Classes[i]; + Classes[i] = NULL; + } + } + } +} + +/** 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; + 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->Config->ports.size(); return val; } +