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-rw-r--r--include/dns.h61
-rw-r--r--src/dns.cpp135
-rw-r--r--src/modules/m_cgiirc.cpp2
-rw-r--r--src/modules/m_testcommand.cpp2
4 files changed, 59 insertions, 141 deletions
diff --git a/include/dns.h b/include/dns.h
index b9ba27e2e..522b58ee5 100644
--- a/include/dns.h
+++ b/include/dns.h
@@ -23,11 +23,7 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#include "socket.h"
#include "base.h"
-struct dns_ip4list
-{
- insp_inaddr ip;
- dns_ip4list *next;
-};
+typedef std::pair<int,std::string> DNSResult;
/**
* Error types that class Resolver can emit to its error method.
@@ -41,25 +37,20 @@ enum ResolverError
};
-/** The DNS class allows fast nonblocking resolution of hostnames
- * and ip addresses. It is based heavily upon firedns by Ian Gulliver.
- * Modules SHOULD avoid using this class to resolve hostnames and IP
- * addresses, as it is a low-level wrapper around the UDP socket routines
- * and is probably not abstracted enough for real use. Please see the
- * Resolver class if you wish to resolve hostnames.
+/** 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
{
private:
- insp_inaddr *binip;
- unsigned char* result;
- unsigned char localbuf[1024];
int t;
int myid;
public:
int dns_getip4(const char* name);
int dns_getname4(const insp_inaddr* ip);
- int dns_getresult();
+ DNSResult dns_getresult();
DNS();
~DNS();
};
@@ -76,11 +67,7 @@ class DNS : public Extensible
*/
class Resolver : public Extensible
{
- private:
- /**
- * The lowlevel DNS object used by Resolver
- */
- DNS Query;
+ protected:
/**
* The input data, either a host or an IP address
*/
@@ -95,13 +82,11 @@ class Resolver : public Extensible
*/
std::string server;
/**
- * The file descriptor used for the DNS lookup
+ * The ID allocated to your lookup. This is a pseud-random number
+ * between 0 and 65535, a value of -1 indicating a failure.
+ * The core uses this to route results to the correct objects.
*/
int myid;
- /**
- * The output data, e.g. a hostname or an IP.
- */
- std::string result;
public:
/**
* Initiate DNS lookup. Your class should not attempt to delete or free these
@@ -114,14 +99,13 @@ class Resolver : public Extensible
* @param forward Set to true to perform a forward lookup (hostname to ip) or false
* to perform a reverse lookup (ip to hostname). Lookups on A records and PTR
* records are supported. CNAME and MX are not supported by this resolver.
- * @param dnsserver This optional parameter specifies an alterate nameserver to use.
- * If it is not specified, or is an empty string, the value of ServerConfig::DNSServer
- * is used instead.
+ * If InspIRCd is compiled with ipv6 support, lookups on AAAA records are preferred
+ * and supported over A records.
* @throw ModuleException This class may throw an instance of ModuleException, in the
- * event there are no more file descriptors, or a similar hard error occurs such as
+ * event a lookup could not be allocated, or a similar hard error occurs such as
* the network being down.
*/
- Resolver(const std::string &source, bool forward, const std::string &dnsserver);
+ Resolver(const std::string &source, bool forward);
/**
* The default destructor does nothing.
*/
@@ -142,7 +126,7 @@ class Resolver : public Extensible
* for reading, and will then dispatch a call to either OnLookupComplete or
* OnError. You should never call this method yourself.
*/
- bool ProcessResult();
+ bool ProcessResult(const std::string &result);
/**
* Returns the file descriptor of this class. This is primarily used by the core
* to determine where in various tables to place a pointer to your class, but it
@@ -152,11 +136,13 @@ class Resolver : public Extensible
};
/**
- * Clear the pointer table used for Resolver classes
+ * 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 writeable
+ * Deal with a Resolver class which has become readable
*/
void dns_deal_with_classes(int fd);
/**
@@ -164,13 +150,4 @@ void dns_deal_with_classes(int fd);
*/
bool dns_add_class(Resolver* r);
-#ifdef THREADED_DNS
-/** This is the handler function for multi-threaded DNS.
- * It cannot be a class member as pthread will not let us
- * create a thread whos handler function is a member of
- * a class (ugh).
- */
-void* dns_task(void* arg);
-#endif
-
#endif
diff --git a/src/dns.cpp b/src/dns.cpp
index a8268aafc..e0cb3ccaa 100644
--- a/src/dns.cpp
+++ b/src/dns.cpp
@@ -69,16 +69,10 @@ typedef connlist::iterator connlist_iter;
DNS* Res = NULL;
-/* As lookups are completed, they are pushed into this result_list */
-std::map<int, std::string> result_list;
connlist connections;
-
int master_socket = -1;
-
Resolver* dns_classes[65536];
-
-insp_inaddr servers[8];
-int i4;
+insp_inaddr myserver;
class s_rr_middle
{
@@ -109,7 +103,6 @@ class s_connection
unsigned char res[512];
unsigned int _class;
QueryType type;
- int want_list;
s_connection()
{
@@ -185,14 +178,13 @@ int s_connection::send_requests(const s_header *h, const int l)
dns_empty_header(payload,h,l);
- /* otherwise send via standard ipv4 boringness */
memset(&addr,0,sizeof(addr));
#ifdef IPV6
- memcpy(&addr.sin6_addr,&servers[0],sizeof(addr.sin6_addr));
+ memcpy(&addr.sin6_addr,&myserver,sizeof(addr.sin6_addr));
addr.sin6_family = AF_FAMILY;
addr.sin6_port = htons(53);
#else
- memcpy(&addr.sin_addr.s_addr,&servers[0],sizeof(addr.sin_addr));
+ memcpy(&addr.sin_addr.s_addr,&myserver,sizeof(addr.sin_addr));
addr.sin_family = AF_FAMILY;
addr.sin_port = htons(53);
#endif
@@ -211,7 +203,6 @@ s_connection* dns_add_query(s_header *h, int &id)
id = rand() % 65536;
s_connection * s = new s_connection();
- /* set header flags */
h->id[0] = s->id[0] = id >> 8;
h->id[1] = s->id[1] = id & 0xFF;
h->flags1 = 0 | FLAGS1_MASK_RD;
@@ -220,7 +211,7 @@ s_connection* dns_add_query(s_header *h, int &id)
h->ancount = 0;
h->nscount = 0;
h->arcount = 0;
- s->want_list = 0;
+
if (connections.find(id) == connections.end())
connections[id] = s;
return s;
@@ -230,11 +221,10 @@ void create_socket()
{
log(DEBUG,"---- BEGIN DNS INITIALIZATION, SERVER=%s ---",Config->DNSServer);
insp_inaddr addr;
- i4 = 0;
srand((unsigned int) TIME);
- memset(servers,'\0',sizeof(insp_inaddr) * 8);
+ memset(&myserver,0,sizeof(insp_inaddr));
if (insp_aton(Config->DNSServer,&addr) > 0)
- memcpy(&servers[i4++],&addr,sizeof(insp_inaddr));
+ memcpy(&myserver,&addr,sizeof(insp_inaddr));
master_socket = socket(PF_PROTOCOL, SOCK_DGRAM, 0);
if (master_socket != -1)
@@ -373,10 +363,9 @@ int DNS::dns_getname4(const insp_inaddr *ip)
#endif
}
-/* Return the next id which is ready.
- * result_list[id] will have been populated with the result string.
+/* Return the next id which is ready, and the result attached to it
*/
-int DNS::dns_getresult()
+DNSResult DNS::dns_getresult()
{
/* retrieve result of DNS query (buffered) */
s_header h;
@@ -387,7 +376,7 @@ int DNS::dns_getresult()
length = recv(master_socket,buffer,sizeof(s_header),0);
if (length < 12)
- return -1;
+ return std::make_pair(-1,"");
dns_fill_header(&h,buffer,length - 12);
@@ -400,7 +389,7 @@ int DNS::dns_getresult()
if (n_iter == connections.end())
{
log(DEBUG,"DNS: got a response for a query we didnt send with fd=%d queryid=%d",master_socket,this_id);
- return -1;
+ return std::make_pair(-1,"");
}
else
{
@@ -410,10 +399,11 @@ int DNS::dns_getresult()
connections.erase(n_iter);
}
unsigned char* a = c->result_ready(h, length);
+ std::string resultstr;
if (a == NULL)
{
- result_list[this_id] = "";
+ resultstr = "";
}
else
{
@@ -421,16 +411,16 @@ int DNS::dns_getresult()
{
char formatted[1024];
snprintf(formatted,1024,"%u.%u.%u.%u",a[0],a[1],a[2],a[3]);
- result_list[this_id] = std::string(formatted);
+ resultstr = std::string(formatted);
}
else
{
- result_list[this_id] = std::string((const char*)a);
+ resultstr = std::string((const char*)a);
}
}
delete c;
- return this_id;
+ return std::make_pair(this_id,resultstr);
}
/** A result is ready, process it
@@ -564,54 +554,6 @@ unsigned char* s_connection::result_ready(s_header &h, int length)
break;
case DNS_QRY_A:
log(DEBUG,"DNS: got a result of type DNS_QRY_A");
- if (this->want_list)
- {
- dns_ip4list *alist = (dns_ip4list *) res; /* we have to trust that this is aligned */
- while ((char *)alist - (char *)res < 700)
- {
- if (rr.type != DNS_QRY_A)
- break;
- if (rr._class != 1)
- break;
- if (rr.rdlength != 4)
- {
- return NULL;
- }
- memcpy(&alist->ip,&h.payload[i],4);
- if ((unsigned)++curanswer >= h.ancount)
- break;
- i += rr.rdlength;
- q = 0;
- while (q == 0 && i < length)
- {
- if (h.payload[i] > 63)
- {
- i += 2;
- q = 1;
- }
- else
- {
- if (h.payload[i] == 0)
- {
- i++;
- q = 1;
- }
- else i += h.payload[i] + 1;
- }
- }
- if (length - i < 10)
- {
- return NULL;
- }
- dns_fill_rr(&rr,&h.payload[i]);
- i += 10;
- alist->next = (dns_ip4list *) dns_align(((char *) alist) + sizeof(dns_ip4list));
- alist = alist->next;
- alist->next = NULL;
- }
- alist->next = NULL;
- break;
- }
memcpy(res,&h.payload[i],rr.rdlength);
res[rr.rdlength] = '\0';
break;
@@ -632,7 +574,7 @@ DNS::~DNS()
{
}
-Resolver::Resolver(const std::string &source, bool forward, const std::string &dnsserver = "") : input(source), fwd(forward), server(dnsserver)
+Resolver::Resolver(const std::string &source, bool forward) : input(source), fwd(forward)
{
if (forward)
{
@@ -651,8 +593,7 @@ Resolver::Resolver(const std::string &source, bool forward, const std::string &d
{
log(DEBUG,"Resolver::Resolver: Could not get an id!");
this->OnError(RESOLVER_NSDOWN);
- ModuleException e("Resolver: Couldnt get an id to make a request");
- throw e;
+ throw ModuleException("Resolver: Couldnt get an id to make a request");
/* We shouldnt get here really */
return;
}
@@ -660,6 +601,14 @@ Resolver::Resolver(const std::string &source, bool forward, const std::string &d
log(DEBUG,"Resolver::Resolver: this->myid=%d",this->myid);
}
+void Resolver::OnLookupComplete(const std::string &result)
+{
+}
+
+void Resolver::OnError(ResolverError e)
+{
+}
+
Resolver::~Resolver()
{
log(DEBUG,"Resolver::~Resolver");
@@ -670,13 +619,11 @@ int Resolver::GetId()
return this->myid;
}
-bool Resolver::ProcessResult()
+bool Resolver::ProcessResult(const std::string &result)
{
log(DEBUG,"Resolver::ProcessResult");
- std::map<int, std::string>::iterator x = result_list.find(this->myid);
-
- if (x == result_list.end())
+ if (!result.length())
{
log(DEBUG,"Resolver::OnError(RESOLVER_NXDOMAIN)");
this->OnError(RESOLVER_NXDOMAIN);
@@ -685,33 +632,27 @@ bool Resolver::ProcessResult()
else
{
- log(DEBUG,"Resolver::OnLookupComplete(%s)",x->second.c_str());
- this->OnLookupComplete(x->second);
- result_list.erase(x);
+ log(DEBUG,"Resolver::OnLookupComplete(%s)",result.c_str());
+ this->OnLookupComplete(result);
return true;
}
}
-void Resolver::OnLookupComplete(const std::string &result)
-{
-}
-
-void Resolver::OnError(ResolverError e)
-{
-}
-
void dns_deal_with_classes(int fd)
{
log(DEBUG,"dns_deal_with_classes(%d)",fd);
if (fd == master_socket)
{
- int id = Res->dns_getresult();
- if (id != -1)
+ DNSResult res = Res->dns_getresult();
+ if (res.first != -1)
{
- log(DEBUG,"Result available, id=%d",id);
- dns_classes[id]->ProcessResult();
- delete dns_classes[id];
- dns_classes[id] = NULL;
+ log(DEBUG,"Result available, id=%d",res.first);
+ if (dns_classes[res.first])
+ {
+ dns_classes[res.first]->ProcessResult(res.second);
+ delete dns_classes[res.first];
+ dns_classes[res.first] = NULL;
+ }
}
}
}
diff --git a/src/modules/m_cgiirc.cpp b/src/modules/m_cgiirc.cpp
index 6426e054a..688da6f05 100644
--- a/src/modules/m_cgiirc.cpp
+++ b/src/modules/m_cgiirc.cpp
@@ -56,7 +56,7 @@ class CGIResolver : public Resolver
bool notify;
public:
CGIResolver(bool NotifyOpers, const std::string &source, bool forward, userrec* u, int userfd, const std::string &type)
- : Resolver(source, forward, ""), typ(type), theirfd(userfd), them(u), notify(NotifyOpers) { }
+ : Resolver(source, forward), typ(type), theirfd(userfd), them(u), notify(NotifyOpers) { }
virtual void OnLookupComplete(const std::string &result)
{
diff --git a/src/modules/m_testcommand.cpp b/src/modules/m_testcommand.cpp
index 1f8aaac1a..3b27d01d9 100644
--- a/src/modules/m_testcommand.cpp
+++ b/src/modules/m_testcommand.cpp
@@ -28,7 +28,7 @@ using namespace std;
class MyResolver : public Resolver
{
public:
- MyResolver(const std::string &source, bool forward, const std::string &dnsserver = "") : Resolver(source, forward, dnsserver) { }
+ MyResolver(const std::string &source, bool forward) : Resolver(source, forward) { }
virtual void OnLookupComplete(const std::string &result)
{
generated by cgit v1.2.3 (git 2.39.1) at 2025-01-02 21:39:42 +0000