/** Represents a dns resource record (rr)
*/
-class ResourceRecord
+struct ResourceRecord
{
- public:
QueryType type; /* Record type */
unsigned int rr_class; /* Record class */
unsigned long ttl; /* Time to live */
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 */
- DNSRequest(InspIRCd* Instance, DNS* dns, insp_inaddr server, int id);
+ DNSRequest(InspIRCd* Instance, DNS* dns, insp_inaddr server, int id, const std::string &original);
~DNSRequest();
DNSInfo ResultIsReady(DNSHeader &h, int length);
int SendRequests(const DNSHeader *header, const int length, QueryType qt);
};
+class CacheTimer : public InspTimer
+{
+ private:
+ InspIRCd* ServerInstance;
+ DNS* dns;
+ public:
+ CacheTimer(InspIRCd* Instance, DNS* thisdns)
+ : InspTimer(3600, Instance->Time(), true), ServerInstance(Instance), dns(thisdns) { }
+
+ virtual void Tick(time_t TIME)
+ {
+ dns->PruneCache();
+ }
+};
+
class RequestTimeout : public InspTimer
{
InspIRCd* ServerInstance;
public:
RequestTimeout(unsigned long n, InspIRCd* SI, DNSRequest* watching, int id) : InspTimer(n, time(NULL)), ServerInstance(SI), watch(watching), watchid(id)
{
- ServerInstance->Log(DEBUG, "New DNS timeout set on %08x", watching);
}
void Tick(time_t TIME)
ServerInstance->Res->Classes[watchid] = NULL;
}
ServerInstance->Res->requests[watchid] = NULL;
- delete watch;
- ServerInstance->Log(DEBUG, "DNS timeout on %08x squished pointer", watch);
+ DELETE(watch);
return;
}
- ServerInstance->Log(DEBUG, "DNS timeout on %08x: result already received!", watch);
}
};
/* Allocate the processing buffer */
-DNSRequest::DNSRequest(InspIRCd* Instance, DNS* dns, insp_inaddr server, int id) : dnsobj(dns)
+DNSRequest::DNSRequest(InspIRCd* Instance, DNS* dns, insp_inaddr server, int id, const std::string &original) : dnsobj(dns)
{
res = new unsigned char[512];
*res = 0;
memcpy(&myserver, &server, sizeof(insp_inaddr));
+ orig = original;
RequestTimeout* RT = new RequestTimeout(Instance->Config->dns_timeout ? Instance->Config->dns_timeout : 5, Instance, this, id);
Instance->Timers->AddTimer(RT); /* The timer manager frees this */
}
}
/** Add a query with a predefined header, and allocate an ID for it. */
-DNSRequest* DNS::AddQuery(DNSHeader *header, int &id)
+DNSRequest* DNS::AddQuery(DNSHeader *header, int &id, const char* original)
{
/* Is the DNS connection down? */
if (this->GetFd() == -1)
while (requests[id])
id = this->PRNG() & DNS::MAX_REQUEST_ID;
- DNSRequest* req = new DNSRequest(ServerInstance, this, this->myserver, id);
+ DNSRequest* req = new DNSRequest(ServerInstance, this, this->myserver, id, original);
header->id[0] = req->id[0] = id >> 8;
header->id[1] = req->id[1] = id & 0xFF;
return req;
}
+int DNS::ClearCache()
+{
+ /* This ensures the buckets are reset to sane levels */
+ int rv = this->cache->size();
+ delete this->cache;
+ this->cache = new dnscache();
+ return rv;
+}
+
+int DNS::PruneCache()
+{
+ 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++;
+
+ delete this->cache;
+ this->cache = newcache;
+ return n;
+}
+
void DNS::Rehash()
{
insp_inaddr addr;
shutdown(this->GetFd(), 2);
close(this->GetFd());
this->SetFd(-1);
+
+ /* Rehash the cache */
+ this->PruneCache();
+ }
+ else
+ {
+ /* Create initial dns cache */
+ this->cache = new dnscache();
}
if (insp_aton(ServerInstance->Config->DNSServer,&addr) > 0)
ServerInstance->Log(DEFAULT," to a true IPv6 environment.");
this->ip6munge = true;
}
- ServerInstance->Log(DEBUG,"Added nameserver '%s'",ServerInstance->Config->DNSServer);
- }
- else
- {
- ServerInstance->Log(DEBUG,"GACK! insp_aton says the nameserver '%s' is invalid!",ServerInstance->Config->DNSServer);
}
/* Initialize mastersocket */
this->SetFd(-1);
}
}
- else
- {
- ServerInstance->Log(DEBUG,"I cant socket() this socket! (%s)",strerror(errno));
- }
/* Have we got a socket and is it nonblocking? */
if (this->GetFd() != -1)
if (bind(this->GetFd(),(sockaddr *)&addr,sizeof(addr)) != 0)
{
/* Failed to bind */
- ServerInstance->Log(DEBUG,"Cant bind DNS fd");
shutdown(this->GetFd(),2);
close(this->GetFd());
this->SetFd(-1);
if (this->GetFd() >= 0)
{
- ServerInstance->Log(DEBUG,"Add master socket %d",this->GetFd());
/* Hook the descriptor into the socket engine */
if (ServerInstance && ServerInstance->SE)
{
/** Initialise the DNS UDP socket so that we can send requests */
DNS::DNS(InspIRCd* Instance) : ServerInstance(Instance)
{
- ServerInstance->Log(DEBUG,"DNS::DNS: Instance = %08x",Instance);
-
/* Clear the Resolver class table */
memset(Classes,0,sizeof(Classes));
/* 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 */
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;
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;
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;
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, insp_ntoa(*ip));
if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_PTR) == -1))
return -1;
return -1;
}
- ServerInstance->Log(DEBUG,"DNS::GetNameForce: %s %d",query, fp);
-
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, ip);
if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_PTR) == -1))
return -1;
int length = recvfrom(this->GetFd(),buffer,sizeof(DNSHeader),0,&from,&x);
- if (length < 0)
- ServerInstance->Log(DEBUG,"Error in recvfrom()! (%s)",strerror(errno));
-
/* Did we get the whole header? */
if (length < 12)
{
/* Nope - something screwed up. */
- ServerInstance->Log(DEBUG,"Whole header not read!");
- return DNSResult(-1,"",0);
+ return DNSResult(-1,"",0,"");
}
/* Check wether the reply came from a different DNS
{
if ((port_from != DNS::QUERY_PORT) || (strcasecmp(ipaddr_from, ServerInstance->Config->DNSServer)))
{
- ServerInstance->Log(DEBUG,"port %d is not 53, or %s is not %s",port_from, ipaddr_from, ServerInstance->Config->DNSServer);
- return DNSResult(-1,"",0);
+ return DNSResult(-1,"",0,"");
}
}
if (!requests[this_id])
{
/* Somehow we got a DNS response for a request we never made... */
- ServerInstance->Log(DEBUG,"DNS: got a response for a query we didnt send with fd=%d queryid=%d",this->GetFd(),this_id);
- return DNSResult(-1,"",0);
+ return DNSResult(-1,"",0,"");
}
else
{
* 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 DNSResult(this_id | ERROR_MASK, data.second, 0);
+ return DNSResult(this_id | ERROR_MASK, data.second, 0, ro);
}
else
{
break;
default:
- ServerInstance->Log(DEBUG,"WARNING: Somehow we made a request for a DNS_QUERY_PTR4 or DNS_QUERY_PTR6, but these arent real rr types!");
break;
}
/* Build the reply with the id and hostname/ip in it */
+ std::string ro = req->orig;
delete req;
- return DNSResult(this_id,resultstr,ttl);
+ return DNSResult(this_id,resultstr,ttl,ro);
}
}
/* 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. */
if (!(header.flags1 & FLAGS_MASK_QR))
return std::make_pair((unsigned char*)NULL,"Not a query result");
if (length - i < 10)
return std::make_pair((unsigned char*)NULL,"Incorrectly sized DNS reply");
+ /* XXX: We actually initialise 'rr' here including its ttl field */
DNS::FillResourceRecord(&rr,&header.payload[i]);
i += 10;
if (rr.type != this->type)
{
shutdown(this->GetFd(), 2);
close(this->GetFd());
+ ServerInstance->Timers->DelTimer(this->PruneTimer);
+ delete 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());
+}
+
+void Resolver::TriggerCachedResult()
+{
+ if (CQ)
+ OnLookupComplete(CQ->data, time_left, true);
}
/** High level abstraction of dns used by application at large */
-Resolver::Resolver(InspIRCd* Instance, const std::string &source, QueryType qt, Module* creator) : ServerInstance(Instance), Creator(creator), input(source), querytype(qt)
+Resolver::Resolver(InspIRCd* Instance, const std::string &source, QueryType qt, bool &cached, Module* creator) : ServerInstance(Instance), Creator(creator), input(source), querytype(qt)
{
- ServerInstance->Log(DEBUG,"Instance: %08x %08x",Instance, ServerInstance);
+ cached = false;
+
+ CQ = ServerInstance->Res->GetCache(source);
+ if (CQ)
+ {
+ time_left = CQ->CalcTTLRemaining();
+ if (!time_left)
+ {
+ ServerInstance->Res->DelCache(source);
+ }
+ else
+ {
+ cached = true;
+ return;
+ }
+ }
insp_inaddr binip;
}
if (this->myid == -1)
{
- ServerInstance->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;
}
-
- ServerInstance->Log(DEBUG,"Resolver::Resolver: this->myid=%d",this->myid);
}
/** Called when an error occurs */
/* Mask off the error bit */
res.id -= ERROR_MASK;
/* Marshall the error to the correct class */
- ServerInstance->Log(DEBUG,"Error available, id=%d",res.id);
if (Classes[res.id])
{
if (ServerInstance && ServerInstance->stats)
}
else
{
- /* It is a non-error result */
- ServerInstance->Log(DEBUG,"Result available, id=%d",res.id);
- /* Marshall the result to the correct class */
+ /* It is a non-error result, marshall the result to the correct class */
if (Classes[res.id])
{
if (ServerInstance && ServerInstance->stats)
ServerInstance->stats->statsDnsGood++;
- Classes[res.id]->OnLookupComplete(res.result, res.ttl);
+
+ 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);
delete Classes[res.id];
Classes[res.id] = NULL;
}
projects / user / henk / code / inspircd.git / blobdiff