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-rw-r--r--include/dns.h48
-rw-r--r--include/inspircd.h2
-rw-r--r--src/dns.cpp207
-rw-r--r--src/inspircd.cpp7
-rw-r--r--src/modules.cpp2
5 files changed, 129 insertions, 137 deletions
diff --git a/include/dns.h b/include/dns.h
index 1f520de33..50febef59 100644
--- a/include/dns.h
+++ b/include/dns.h
@@ -38,21 +38,8 @@ enum ResolverError
RESOLVER_BADIP = 4
};
-
-/** DNS is a singleton class used by the core to dispatch dns
- * requests to the dns server, and route incoming dns replies
- * back to Resolver objects, based upon the request ID. You
- * should never use this class yourself.
- */
-class DNS : public Extensible
-{
- public:
- int GetIP(const char* name);
- int GetName(const insp_inaddr* ip);
- DNSResult GetResult();
- DNS();
- ~DNS();
-};
+class DNSRequest;
+class DNSHeader;
/**
* The Resolver class is a high-level abstraction for resolving DNS entries.
@@ -132,19 +119,24 @@ class Resolver : public Extensible
int GetId();
};
-/**
- * Clear the pointer table used for Resolver classes,
- * translate ServerConfig::DNSServer into an insp_inaddr,
- * establish binding on UDP socket for DNS requests.
- */
-void init_dns();
-/**
- * Deal with a Resolver class which has become readable
- */
-void dns_deal_with_classes(int fd);
-/**
- * Add a resolver class to our active table
+/** DNS is a singleton class used by the core to dispatch dns
+ * requests to the dns server, and route incoming dns replies
+ * back to Resolver objects, based upon the request ID. You
+ * should never use this class yourself.
*/
-bool dns_add_class(Resolver* r);
+class DNS : public Extensible
+{
+ private:
+ insp_inaddr myserver;
+ public:
+ int GetIP(const char* name);
+ int GetName(const insp_inaddr* ip);
+ DNSResult GetResult();
+ void MarshallReads(int fd);
+ bool AddResolverClass(Resolver* r);
+ DNSRequest* DNSAddQuery(DNSHeader *header, int &id);
+ DNS();
+ ~DNS();
+};
#endif
diff --git a/include/inspircd.h b/include/inspircd.h
index 8e75c256c..e698efe21 100644
--- a/include/inspircd.h
+++ b/include/inspircd.h
@@ -103,6 +103,7 @@ class InspIRCd : public classbase
CommandParser* Parser;
SocketEngine* SE;
serverstats* stats;
+ DNS* Res;
std::string GetRevision();
std::string GetVersionString();
@@ -113,7 +114,6 @@ class InspIRCd : public classbase
InspIRCd(int argc, char** argv);
void DoOneIteration(bool process_module_sockets);
int Run();
-
};
/* Miscellaneous stuff here, moved from inspircd_io.h */
diff --git a/src/dns.cpp b/src/dns.cpp
index b9ecffa06..66e4edaed 100644
--- a/src/dns.cpp
+++ b/src/dns.cpp
@@ -43,89 +43,93 @@ using namespace std;
#include "socketengine.h"
#include "configreader.h"
+/* We need these */
extern InspIRCd* ServerInstance;
extern ServerConfig* Config;
-extern time_t TIME;
-extern userrec* fd_ref_table[MAX_DESCRIPTORS];
+/* Query and resource record types */
enum QueryType
{
- DNS_QRY_A = 1,
- DNS_QRY_PTR = 12
+ DNS_QRY_A = 1, /* 'A' record: an IP address */
+ DNS_QRY_PTR = 12 /* 'PTR' record: a hostname */
};
+/* Masks to mask off the responses we get from the DNSRequest methods */
enum QueryInfo
{
- ERROR_MASK = 0x10000
+ ERROR_MASK = 0x10000 /* Result is an error */
};
+/* Flags which can be ORed into a request or reply for different meanings */
enum QueryFlags
{
- FLAGS_MASK_RD = 0x01,
+ FLAGS_MASK_RD = 0x01, /* Recursive */
FLAGS_MASK_TC = 0x02,
- FLAGS_MASK_AA = 0x04,
+ FLAGS_MASK_AA = 0x04, /* Authoritative */
FLAGS_MASK_OPCODE = 0x78,
FLAGS_MASK_QR = 0x80,
- FLAGS_MASK_RCODE = 0x0F,
+ FLAGS_MASK_RCODE = 0x0F, /* Request */
FLAGS_MASK_Z = 0x70,
FLAGS_MASK_RA = 0x80
};
-class DNSRequest;
-typedef std::map<int,DNSRequest*> connlist;
-typedef connlist::iterator connlist_iter;
-
-DNS* Res = NULL;
+/* Master file descriptor - all DNS requests go out over this socket.
+ */
+int MasterDNSSocket = -1;
-connlist connections;
-int master_socket = -1;
+/* Lookup table of Resolver classes. Because the request ID can be between
+ * 0 and 65535 of these, we have 65536 of them. This could be a map, saving
+ * some ram, but that will also slow down DNS requests, and the DNS request
+ * mechanism needs to be pretty fast.
+ */
Resolver* dns_classes[65536];
-insp_inaddr myserver;
/* Represents a dns resource record (rr) */
class ResourceRecord
{
public:
- QueryType type;
- unsigned int rr_class;
- unsigned long ttl;
- unsigned int rdlength;
+ 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
{
public:
- unsigned char id[2];
- unsigned int flags1;
- unsigned int flags2;
+ unsigned char id[2]; /* Request id */
+ unsigned int flags1; /* Flags */
+ unsigned int flags2; /* Flags */
unsigned int qdcount;
- unsigned int ancount;
- unsigned int nscount;
+ unsigned int ancount; /* Answer count */
+ unsigned int nscount; /* Nameserver count */
unsigned int arcount;
- unsigned char payload[512];
+ 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
+/* 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];
- unsigned char* res;
- unsigned int rr_class;
- QueryType type;
-
- DNSRequest()
+ unsigned char id[2]; /* Request id */
+ unsigned char* res; /* Result processing buffer */
+ unsigned int rr_class; /* Request class */
+ QueryType type; /* Request type */
+ insp_inaddr myserver; /* DNS server address*/
+
+ /* Allocate the processing buffer */
+ DNSRequest(insp_inaddr server)
{
res = new unsigned char[512];
*res = 0;
+ memcpy(&myserver, &server, sizeof(insp_inaddr));
}
+ /* Deallocate the processing buffer */
~DNSRequest()
{
delete[] res;
@@ -138,6 +142,15 @@ class DNSRequest
int SendRequests(const DNSHeader *header, const int length, QueryType qt);
};
+/* A set of requests keyed by request id */
+typedef std::map<int,DNSRequest*> requestlist;
+
+/* An iterator into a set of requests */
+typedef requestlist::iterator requestlist_iter;
+
+/* Declare our map */
+requestlist requests;
+
/*
* Optimized by brain, these were using integer division and modulus.
* We can use logic shifts and logic AND to replace these even divisions
@@ -145,7 +158,9 @@ class DNSRequest
* but of course, more impressive). Also made these inline.
*/
-inline void dns_fill_rr(ResourceRecord* rr, const unsigned char *input)
+
+/* Fill a ResourceRecord class based on raw data input */
+inline void DNSFillResourceRecord(ResourceRecord* rr, const unsigned char *input)
{
rr->type = (QueryType)((input[0] << 8) + input[1]);
rr->rr_class = (input[2] << 8) + input[3];
@@ -153,7 +168,8 @@ inline void dns_fill_rr(ResourceRecord* rr, const unsigned char *input)
rr->rdlength = (input[8] << 8) + input[9];
}
-inline void dns_fill_header(DNSHeader *header, const unsigned char *input, const int length)
+/* Fill a DNSHeader class based on raw data input of a given length */
+inline void DNSFillHeader(DNSHeader *header, const unsigned char *input, const int length)
{
header->id[0] = input[0];
header->id[1] = input[1];
@@ -166,7 +182,8 @@ inline void dns_fill_header(DNSHeader *header, const unsigned char *input, const
memcpy(header->payload,&input[12],length);
}
-inline void dns_empty_header(unsigned char *output, const DNSHeader *header, const int length)
+/* Empty a DNSHeader class out into raw data, ready for transmission */
+inline void DNSEmptyHeader(unsigned char *output, const DNSHeader *header, const int length)
{
output[0] = header->id[0];
output[1] = header->id[1];
@@ -183,7 +200,7 @@ inline void dns_empty_header(unsigned char *output, const DNSHeader *header, con
memcpy(&output[12],header->payload,length);
}
-
+/* Send requests we have previously built down the UDP socket */
int DNSRequest::SendRequests(const DNSHeader *header, const int length, QueryType qt)
{
insp_sockaddr addr;
@@ -192,7 +209,7 @@ int DNSRequest::SendRequests(const DNSHeader *header, const int length, QueryTyp
this->rr_class = 1;
this->type = qt;
- dns_empty_header(payload,header,length);
+ DNSEmptyHeader(payload,header,length);
memset(&addr,0,sizeof(addr));
#ifdef IPV6
@@ -204,7 +221,7 @@ int DNSRequest::SendRequests(const DNSHeader *header, const int length, QueryTyp
addr.sin_family = AF_FAMILY;
addr.sin_port = htons(53);
#endif
- if (sendto(master_socket, payload, length + 12, 0, (sockaddr *) &addr, sizeof(addr)) == -1)
+ if (sendto(MasterDNSSocket, payload, length + 12, 0, (sockaddr *) &addr, sizeof(addr)) == -1)
{
log(DEBUG,"Error in sendto!");
return -1;
@@ -213,11 +230,11 @@ int DNSRequest::SendRequests(const DNSHeader *header, const int length, QueryTyp
return 0;
}
-DNSRequest* DNSAddQuery(DNSHeader *header, int &id)
+/* Add a query with a predefined header, and allocate an ID for it. */
+DNSRequest* DNS::DNSAddQuery(DNSHeader *header, int &id)
{
-
id = rand() % 65536;
- DNSRequest* req = new DNSRequest();
+ DNSRequest* req = new DNSRequest(this->myserver);
header->id[0] = req->id[0] = id >> 8;
header->id[1] = req->id[1] = id & 0xFF;
@@ -228,34 +245,36 @@ DNSRequest* DNSAddQuery(DNSHeader *header, int &id)
header->nscount = 0;
header->arcount = 0;
- if (connections.find(id) == connections.end())
- connections[id] = req;
+ if (requests.find(id) == requests.end())
+ requests[id] = req;
/* According to the C++ spec, new never returns NULL. */
return req;
}
-void DNSCreateSocket()
+/* Initialise the DNS UDP socket so that we can send requests */
+DNS::DNS()
{
- log(DEBUG,"---- BEGIN DNS INITIALIZATION, SERVER=%s ---",Config->DNSServer);
+ log(DEBUG,"----- Initialize dns class ----- ");
+ memset(dns_classes,0,sizeof(dns_classes));
insp_inaddr addr;
- srand((unsigned int) TIME);
+ srand((unsigned int)time(NULL));
memset(&myserver,0,sizeof(insp_inaddr));
if (insp_aton(Config->DNSServer,&addr) > 0)
memcpy(&myserver,&addr,sizeof(insp_inaddr));
- master_socket = socket(PF_PROTOCOL, SOCK_DGRAM, 0);
- if (master_socket != -1)
+ MasterDNSSocket = socket(PF_PROTOCOL, SOCK_DGRAM, 0);
+ if (MasterDNSSocket != -1)
{
log(DEBUG,"Set query socket nonblock");
- if (fcntl(master_socket, F_SETFL, O_NONBLOCK) != 0)
+ if (fcntl(MasterDNSSocket, F_SETFL, O_NONBLOCK) != 0)
{
- shutdown(master_socket,2);
- close(master_socket);
- master_socket = -1;
+ shutdown(MasterDNSSocket,2);
+ close(MasterDNSSocket);
+ MasterDNSSocket = -1;
}
}
- if (master_socket != -1)
+ if (MasterDNSSocket != -1)
{
#ifdef IPV6
insp_sockaddr addr;
@@ -271,19 +290,19 @@ void DNSCreateSocket()
addr.sin_addr.s_addr = INADDR_ANY;
#endif
log(DEBUG,"Binding query port");
- if (bind(master_socket,(sockaddr *)&addr,sizeof(addr)) != 0)
+ if (bind(MasterDNSSocket,(sockaddr *)&addr,sizeof(addr)) != 0)
{
log(DEBUG,"Cant bind with source port = 0");
- shutdown(master_socket,2);
- close(master_socket);
- master_socket = -1;
+ shutdown(MasterDNSSocket,2);
+ close(MasterDNSSocket);
+ MasterDNSSocket = -1;
}
- if (master_socket >= 0)
+ if (MasterDNSSocket >= 0)
{
log(DEBUG,"Attach query port to socket engine");
if (ServerInstance && ServerInstance->SE)
- ServerInstance->SE->AddFd(master_socket,true,X_ESTAB_DNS);
+ ServerInstance->SE->AddFd(MasterDNSSocket,true,X_ESTAB_DNS);
}
}
}
@@ -383,7 +402,7 @@ DNSResult DNS::GetResult()
unsigned char buffer[sizeof(DNSHeader)];
/* Attempt to read a header */
- length = recv(master_socket,buffer,sizeof(DNSHeader),0);
+ length = recv(MasterDNSSocket,buffer,sizeof(DNSHeader),0);
/* Did we get the whole header? */
if (length < 12)
@@ -391,7 +410,7 @@ DNSResult DNS::GetResult()
return std::make_pair(-1,"");
/* Put the read header info into a header class */
- dns_fill_header(&header,buffer,length - 12);
+ DNSFillHeader(&header,buffer,length - 12);
/* Get the id of this request.
* Its a 16 bit value stored in two char's,
@@ -400,19 +419,19 @@ DNSResult DNS::GetResult()
unsigned long this_id = header.id[1] + (header.id[0] << 8);
/* Do we have a pending request matching this id? */
- connlist_iter n_iter = connections.find(this_id);
- if (n_iter == connections.end())
- {
+ requestlist_iter n_iter = requests.find(this_id);
+ if (n_iter == requests.end())
+ {
/* 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",master_socket,this_id);
- return std::make_pair(-1,"");
- }
- else
- {
+ log(DEBUG,"DNS: got a response for a query we didnt send with fd=%d queryid=%d",MasterDNSSocket,this_id);
+ return std::make_pair(-1,"");
+ }
+ else
+ {
/* Remove the query from the list of pending queries */
req = (DNSRequest*)n_iter->second;
- connections.erase(n_iter);
- }
+ requests.erase(n_iter);
+ }
/* 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
@@ -519,7 +538,7 @@ DNSInfo DNSRequest::ResultIsReady(DNSHeader &header, int length)
if (length - i < 10)
return std::make_pair((unsigned char*)NULL,"Incorrectly sized DNS reply");
- dns_fill_rr(&rr,&header.payload[i]);
+ DNSFillResourceRecord(&rr,&header.payload[i]);
i += 10;
if (rr.type != this->type)
{
@@ -587,12 +606,10 @@ DNSInfo DNSRequest::ResultIsReady(DNSHeader &header, int length)
return std::make_pair(res,"No error");;
}
-DNS::DNS()
-{
-}
-
DNS::~DNS()
{
+ shutdown(MasterDNSSocket, 2);
+ close(MasterDNSSocket);
}
Resolver::Resolver(const std::string &source, bool forward) : input(source), fwd(forward)
@@ -600,7 +617,7 @@ Resolver::Resolver(const std::string &source, bool forward) : input(source), fwd
if (forward)
{
log(DEBUG,"Resolver: Forward lookup on %s",source.c_str());
- this->myid = Res->GetIP(source.c_str());
+ this->myid = ServerInstance->Res->GetIP(source.c_str());
}
else
{
@@ -609,7 +626,7 @@ Resolver::Resolver(const std::string &source, bool forward) : input(source), fwd
if (insp_aton(source.c_str(), &binip) > 0)
{
/* Valid ip address */
- this->myid = Res->GetName(&binip);
+ this->myid = ServerInstance->Res->GetName(&binip);
}
else
{
@@ -630,10 +647,6 @@ Resolver::Resolver(const std::string &source, bool forward) : input(source), fwd
log(DEBUG,"Resolver::Resolver: this->myid=%d",this->myid);
}
-//void Resolver::OnLookupComplete(const std::string &result)
-//{
-//}
-
void Resolver::OnError(ResolverError e, const std::string &errormessage)
{
}
@@ -648,12 +661,12 @@ int Resolver::GetId()
return this->myid;
}
-void dns_deal_with_classes(int fd)
+void DNS::MarshallReads(int fd)
{
log(DEBUG,"dns_deal_with_classes(%d)",fd);
- if (fd == master_socket)
+ if (fd == MasterDNSSocket)
{
- DNSResult res = Res->GetResult();
+ DNSResult res = this->GetResult();
if (res.first != -1)
{
if (res.first & ERROR_MASK)
@@ -682,35 +695,23 @@ void dns_deal_with_classes(int fd)
}
}
-bool dns_add_class(Resolver* r)
+bool DNS::AddResolverClass(Resolver* r)
{
- log(DEBUG,"dns_add_class");
if ((r) && (r->GetId() > -1))
{
if (!dns_classes[r->GetId()])
{
- log(DEBUG,"dns_add_class: added class");
dns_classes[r->GetId()] = r;
return true;
}
else
- {
- log(DEBUG,"Space occupied!");
return false;
- }
}
else
{
- log(DEBUG,"Bad class");
delete r;
return true;
}
}
-void init_dns()
-{
- Res = new DNS();
- memset(dns_classes,0,sizeof(dns_classes));
- DNSCreateSocket();
-}
diff --git a/src/inspircd.cpp b/src/inspircd.cpp
index 23a4bb496..bcd1614d3 100644
--- a/src/inspircd.cpp
+++ b/src/inspircd.cpp
@@ -817,11 +817,10 @@ void InspIRCd::DoOneIteration(bool process_module_sockets)
case X_ESTAB_DNS:
/* Handles instances of the Resolver class,
- * a simple class extended by modules for
+ * a simple class extended by modules and the core for
* nonblocking resolving of addresses.
*/
-
- dns_deal_with_classes(activefds[activefd]);
+ this->Res->MarshallReads(activefds[activefd]);
break;
case X_LISTEN:
@@ -895,7 +894,7 @@ int InspIRCd::Run()
{
/* Until THIS point, ServerInstance == NULL */
- init_dns();
+ this->Res = new DNS();
LoadAllModules(this);
diff --git a/src/modules.cpp b/src/modules.cpp
index fbdac43d2..9bb8e9a05 100644
--- a/src/modules.cpp
+++ b/src/modules.cpp
@@ -632,7 +632,7 @@ bool Server::DelModeWatcher(ModeWatcher* mw)
bool Server::AddResolver(Resolver* r)
{
- return dns_add_class(r);
+ return ServerInstance->Res->AddResolverClass(r);
}
int Server::CountUsers(chanrec* c)
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-16 03:40:50 +0000