#include <map>
#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;
+using namespace std;
+using irc::sockets::insp_sockaddr;
+using irc::sockets::insp_inaddr;
+using irc::sockets::insp_ntoa;
+using irc::sockets::insp_aton;
/* Masks to mask off the responses we get from the DNSRequest methods */
enum QueryInfo
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) */
/* Allocate the processing buffer */
- DNSRequest(insp_inaddr server)
+ DNSRequest(DNS* dns, insp_inaddr server) : dnsobj(dns)
{
res = new unsigned char[512];
*res = 0;
addr.sin_family = AF_FAMILY;
addr.sin_port = htons(DNS::QUERY_PORT);
#endif
- if (sendto(DNS::GetMasterSocket(), payload, length + 12, 0, (sockaddr *) &addr, sizeof(addr)) == -1)
- {
- log(DEBUG,"Error in sendto!");
+ if (sendto(dnsobj->GetFd(), payload, length + 12, 0, (sockaddr *) &addr, sizeof(addr)) == -1)
return -1;
- }
return 0;
}
/* Add a query with a predefined header, and allocate an ID for it. */
DNSRequest* DNS::AddQuery(DNSHeader *header, int &id)
{
+ /* Is the DNS connection down? */
+ if (this->GetFd() == -1)
+ return NULL;
+
+ /* Are there already the max number of requests on the go? */
if (requests.size() == DNS::MAX_REQUEST_ID + 1)
return NULL;
+ /* Create an id */
id = this->PRNG() & DNS::MAX_REQUEST_ID;
- /* This id is already 'in flight', pick another.
- * -- Thanks jilles
- */
+ /* If this id is already 'in flight', pick another. */
while (requests.find(id) != requests.end())
id = this->PRNG() & DNS::MAX_REQUEST_ID;
- DNSRequest* req = new DNSRequest(this->myserver);
+ DNSRequest* req = new DNSRequest(this, this->myserver);
header->id[0] = req->id[0] = id >> 8;
header->id[1] = req->id[1] = id & 0xFF;
return req;
}
-int DNS::GetMasterSocket()
-{
- return MasterSocket;
-}
-
/* Initialise the DNS UDP socket so that we can send requests */
-DNS::DNS()
+DNS::DNS(InspIRCd* Instance) : ServerInstance(Instance)
{
+ ServerInstance->Log(DEBUG,"DNS::DNS: Instance = %08x",Instance);
+
insp_inaddr addr;
/* Clear the Resolver class table */
memset(&myserver,0,sizeof(insp_inaddr));
/* Convert the nameserver address into an insp_inaddr */
- if (insp_aton(Config->DNSServer,&addr) > 0)
+ if (insp_aton(ServerInstance->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))
+ {
+ /* These dont come back looking like they did when they went in.
+ * We're forced to turn some checks off.
+ * If anyone knows how to fix this, let me know. --Brain
+ */
+ ServerInstance->Log(DEFAULT,"WARNING: Using IPv4 addresses over IPv6 forces some DNS checks to be disabled.");
+ ServerInstance->Log(DEFAULT," This should not cause a problem, however it is recommended you migrate");
+ 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 */
- MasterSocket = socket(PF_PROTOCOL, SOCK_DGRAM, 0);
- if (MasterSocket != -1)
+ this->SetFd(socket(PF_PROTOCOL, SOCK_DGRAM, 0));
+ if (this->GetFd() != -1)
{
/* Did it succeed? */
- if (fcntl(MasterSocket, F_SETFL, O_NONBLOCK) != 0)
+ if (fcntl(this->GetFd(), F_SETFL, O_NONBLOCK) != 0)
{
/* Couldn't make the socket nonblocking */
- shutdown(MasterSocket,2);
- close(MasterSocket);
- MasterSocket = -1;
+ shutdown(this->GetFd(),2);
+ close(this->GetFd());
+ 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 (MasterSocket != -1)
+ if (this->GetFd() != -1)
{
#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));
+ addr.sin6_addr = in6addr_any;
#else
insp_sockaddr addr;
memset(&addr,0,sizeof(addr));
addr.sin_addr.s_addr = INADDR_ANY;
#endif
/* Bind the port */
- if (bind(MasterSocket,(sockaddr *)&addr,sizeof(addr)) != 0)
+ if (bind(this->GetFd(),(sockaddr *)&addr,sizeof(addr)) != 0)
{
/* Failed to bind */
- log(DEBUG,"Cant bind DNS::MasterSocket");
- shutdown(MasterSocket,2);
- close(MasterSocket);
- MasterSocket = -1;
+ ServerInstance->Log(DEBUG,"Cant bind DNS fd");
+ shutdown(this->GetFd(),2);
+ close(this->GetFd());
+ this->SetFd(-1);
}
- if (MasterSocket >= 0)
+ if (this->GetFd() >= 0)
{
+ ServerInstance->Log(DEBUG,"Add master socket %d",this->GetFd());
/* 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->Log(DEFAULT,"Internal error starting DNS - hostnames will NOT resolve.");
+ shutdown(this->GetFd(),2);
+ close(this->GetFd());
+ this->SetFd(-1);
+ }
+ }
}
}
}
return id;
}
+/* Start lookup of an hostname to an IPv6 address */
+int DNS::GetIP6(const char *name)
+{
+ DNSHeader h;
+ int id;
+ int length;
+
+ if ((length = this->MakePayload(name, DNS_QUERY_AAAA, 1, (unsigned char*)&h.payload)) == -1)
+ return -1;
+
+ DNSRequest* req = this->AddQuery(&h, id);
+
+ if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_AAAA) == -1))
+ return -1;
+
+ return id;
+}
+
+/* Start lookup of a cname to another name */
+int DNS::GetCName(const char *alias)
+{
+ DNSHeader h;
+ int id;
+ int length;
+
+ if ((length = this->MakePayload(alias, DNS_QUERY_CNAME, 1, (unsigned char*)&h.payload)) == -1)
+ return -1;
+
+ DNSRequest* req = this->AddQuery(&h, id);
+
+ if ((!req) || (req->SendRequests(&h, length, DNS_QUERY_CNAME) == -1))
+ return -1;
+
+ return id;
+}
+
/* Start lookup of an IP address to a hostname */
int DNS::GetName(const insp_inaddr *ip)
{
-#ifdef IPV6
- return -1;
-#else
- char query[29];
+ char query[128];
DNSHeader h;
int id;
int length;
+#ifdef IPV6
+ 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);
+
+ 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)
+{
+ 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;
+ }
+
+ 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;
return -1;
return id;
+}
+
+void DNS::MakeIP6Int(char* query, const in6_addr *ip)
+{
+#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
}
const char* ipaddr_from = "";
unsigned short int port_from = 0;
- int length = recvfrom(MasterSocket,buffer,sizeof(DNSHeader),0,&from,&x);
+ 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 std::make_pair(-1,"");
+ }
/* Check wether the reply came from a different DNS
* server to the one we sent it to, or the source-port
* -- Thanks jilles for pointing this one out.
*/
#ifdef IPV6
- ipaddr_from = insp_ntoa(((sockaddr_in*)&from)->sin6_addr);
- port_from = ntohs(((sockaddr_in*)&from)->sin6_port);
+ 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);
#endif
- if ((port_from != DNS::QUERY_PORT) || (strcasecmp(ipaddr_from, Config->DNSServer)))
- return std::make_pair(-1,"");
+ /* 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)))
+ {
+ ServerInstance->Log(DEBUG,"port %d is not 53, or %s is not %s",port_from, ipaddr_from, ServerInstance->Config->DNSServer);
+ return std::make_pair(-1,"");
+ }
+ }
/* Put the read header info into a header class */
DNS::FillHeader(&header,buffer,length - 12);
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",MasterSocket,this_id);
+ ServerInstance->Log(DEBUG,"DNS: got a response for a query we didnt send with fd=%d queryid=%d",this->GetFd(),this_id);
return std::make_pair(-1,"");
}
else
}
else
{
+ char formatted[128];
+
/* Forward lookups come back as binary data. We must format them into ascii */
- if (req->type == DNS_QUERY_A)
- {
- char formatted[16];
- snprintf(formatted,16,"%u.%u.%u.%u",data.first[0],data.first[1],data.first[2],data.first[3]);
- resultstr = formatted;
- }
- else
+ switch (req->type)
{
- /* Reverse lookups just come back as char* */
- resultstr = std::string((const char*)data.first);
+ case DNS_QUERY_A:
+ snprintf(formatted,16,"%u.%u.%u.%u",data.first[0],data.first[1],data.first[2],data.first[3]);
+ resultstr = formatted;
+ break;
+
+ 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)));
+ char* c = strstr(formatted,":0:");
+ if (c != NULL)
+ {
+ memmove(c+1,c+2,strlen(c+2) + 1);
+ c += 2;
+ while (memcmp(c,"0:",2) == 0)
+ memmove(c,c+2,strlen(c+2) + 1);
+ if (memcmp(c,"0",2) == 0)
+ *c = 0;
+ if (memcmp(formatted,"0::",3) == 0)
+ 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 = "0" + resultstr;
+ }
+ break;
+
+ case DNS_QUERY_CNAME:
+ /* Identical handling to PTR */
+
+ case DNS_QUERY_PTR:
+ /* Reverse lookups just come back as char* */
+ resultstr = std::string((const char*)data.first);
+ 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 */
switch (rr.type)
{
+ case DNS_QUERY_CNAME:
+ /* CNAME and PTR have the same processing code */
case DNS_QUERY_PTR:
o = 0;
q = 0;
}
res[o] = 0;
break;
+ case DNS_QUERY_AAAA:
+ memcpy(res,&header.payload[i],rr.rdlength);
+ res[rr.rdlength] = 0;
+ break;
case DNS_QUERY_A:
memcpy(res,&header.payload[i],rr.rdlength);
res[rr.rdlength] = 0;
- break;
+ break;
default:
memcpy(res,&header.payload[i],rr.rdlength);
res[rr.rdlength] = 0;
- break;
+ break;
}
return std::make_pair(res,"No error");;
}
/* Close the master socket */
DNS::~DNS()
{
- shutdown(MasterSocket, 2);
- close(MasterSocket);
+ shutdown(this->GetFd(), 2);
+ close(this->GetFd());
}
/* High level abstraction of dns used by application at large */
-Resolver::Resolver(const std::string &source, bool forward) : input(source), fwd(forward)
+Resolver::Resolver(InspIRCd* Instance, const std::string &source, QueryType qt) : ServerInstance(Instance), input(source), querytype(qt)
{
- if (forward)
- {
- log(DEBUG,"Resolver: Forward lookup on %s",source.c_str());
- this->myid = ServerInstance->Res->GetIP(source.c_str());
- }
- else
+ ServerInstance->Log(DEBUG,"Instance: %08x %08x",Instance, ServerInstance);
+
+ insp_inaddr binip;
+
+ switch (querytype)
{
- log(DEBUG,"Resolver: Reverse lookup on %s",source.c_str());
- insp_inaddr binip;
- if (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;
- }
+ case DNS_QUERY_A:
+ this->myid = ServerInstance->Res->GetIP(source.c_str());
+ break;
+
+ case DNS_QUERY_PTR:
+ if (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);
+ 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;
+
+ case DNS_QUERY_CNAME:
+ this->myid = ServerInstance->Res->GetCName(source.c_str());
+ break;
+
+ default:
+ this->myid = -1;
+ break;
}
if (this->myid == -1)
{
- log(DEBUG,"Resolver::Resolver: Could not get an id!");
+ 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;
}
- log(DEBUG,"Resolver::Resolver: this->myid=%d",this->myid);
+ ServerInstance->Log(DEBUG,"Resolver::Resolver: this->myid=%d",this->myid);
}
void Resolver::OnError(ResolverError e, const std::string &errormessage)
}
/* Process a socket read event */
-void DNS::MarshallReads(int fd)
+void DNS::HandleEvent(EventType et)
{
- /* We are only intrested in our single fd */
- if (fd == GetMasterSocket())
+ ServerInstance->Log(DEBUG,"Marshall reads: %d",this->GetFd());
+ /* Fetch the id and result of the next available packet */
+ DNSResult res = this->GetResult();
+ /* Is there a usable request id? */
+ if (res.first != -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.first & ERROR_MASK)
{
- /* Its an error reply */
- if (res.first & ERROR_MASK)
+ /* Mask off the error bit */
+ res.first -= ERROR_MASK;
+ /* Marshall the error to the correct class */
+ ServerInstance->Log(DEBUG,"Error available, id=%d",res.first);
+ if (Classes[res.first])
{
- /* 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.first]->OnError(RESOLVER_NXDOMAIN, res.second);
+ delete Classes[res.first];
+ Classes[res.first] = NULL;
}
- else
+ }
+ else
+ {
+ /* It is a non-error result */
+ ServerInstance->Log(DEBUG,"Result available, id=%d",res.first);
+ /* Marshall the result to the correct class */
+ if (Classes[res.first])
{
- /* 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->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->statsDns++;
}
}
projects / user / henk / code / inspircd.git / blobdiff