]> git.netwichtig.de Git - user/henk/code/inspircd.git/blobdiff - src/dns.cpp
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[user/henk/code/inspircd.git] / src / dns.cpp
index 738fd01167665f525604df375fa62360e522c9de..efb690dc248cd90f6eb0860c298d25b8ee6e7e4c 100644 (file)
@@ -36,9 +36,12 @@ using namespace std;
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include "dns.h"
+#include "inspircd.h"
 #include "helperfuncs.h"
+#include "socketengine.h"
 
-extern int statsAccept,statsRefused,statsUnknown,statsCollisions,statsDns,statsDnsGood,statsDnsBad,statsConnects,statsSent,statsRecv;
+extern InspIRCd* ServerInstance;
+extern ServerConfig* Config;
 
 #define max(a,b) (a > b ? a : b)
 #define DNS_MAX              8                    /* max number of nameservers used */
@@ -152,10 +155,12 @@ void dns_empty_header(unsigned char *output, const s_header *header, const int l
 }
 
 void dns_close(int fd) { /* close query */
+       log(DEBUG,"DNS: dns_close on fd %d",fd);
        if (fd == lastcreate) {
                wantclose = 1;
                return;
        }
+       shutdown(fd,2);
        close(fd);
        return;
 }
@@ -246,6 +251,7 @@ static s_connection *dns_add_query(s_header *h) { /* build DNS query, add to lis
                s->fd = socket(PF_INET, SOCK_DGRAM, 0);
                if (s->fd != -1) {
                        if (fcntl(s->fd, F_SETFL, O_NONBLOCK) != 0) {
+                               shutdown(s->fd,2);
                                close(s->fd);
                                s->fd = -1;
                        }
@@ -257,6 +263,7 @@ static s_connection *dns_add_query(s_header *h) { /* build DNS query, add to lis
                        addr.sin_port = 0;
                        addr.sin_addr.s_addr = INADDR_ANY;
                        if (bind(s->fd,(sockaddr *)&addr,sizeof(addr)) != 0) {
+                               shutdown(s->fd,2);
                                close(s->fd);
                                s->fd = -1;
                        }
@@ -270,6 +277,7 @@ static s_connection *dns_add_query(s_header *h) { /* build DNS query, add to lis
        connection_head = s;
 
        if (wantclose == 1) {
+               shutdown(lastcreate,2);
                close(lastcreate);
                wantclose = 0;
        }
@@ -281,7 +289,7 @@ static int dns_build_query_payload(const char * const name, const unsigned short
        short payloadpos;
        const char * tempchr, * tempchr2;
        unsigned short l;
-       
+
        payloadpos = 0;
        tempchr2 = name;
 
@@ -408,12 +416,6 @@ char* DNS::dns_ntoa4(const in_addr * const ip) { /* numeric to ascii: convert 4p
        return dns_ntoa4_s(ip,r);
 }
 
-char* DNS::dns_ntoa4_r(const in_addr *ip) { /* numeric to ascii (reentrant): convert 4part IP addr struct to new string */
-       char *r;
-       r = new char[256];
-       return dns_ntoa4_s(ip,r);
-}
-
 char* DNS::dns_ntoa4_s(const in_addr *ip, char *r) { /* numeric to ascii (buffered): convert 4part IP addr struct to given string */
        unsigned char *m;
        m = (unsigned char *)&ip->s_addr;
@@ -422,18 +424,8 @@ char* DNS::dns_ntoa4_s(const in_addr *ip, char *r) { /* numeric to ascii (buffer
 }
 
 char* DNS::dns_getresult(const int cfd) { /* retrieve result of DNS query */
-       static char r[RESULTSIZE];
-       return dns_getresult_s(cfd,r);
-}
-
-char* DNS::dns_getresult_r(const int cfd) { /* retrieve result of DNS query (reentrant) */
-       char *r;
-       r = new char[RESULTSIZE];
-       if(dns_getresult_s(cfd,r) == NULL) {
-               delete r;
-               return NULL;
-       }
-       return r;
+       log(DEBUG,"DNS: dns_getresult with cfd=%d",cfd);
+       return dns_getresult_s(cfd,this->localbuf);
 }
 
 char* DNS::dns_getresult_s(const int cfd, char *res) { /* retrieve result of DNS query (buffered) */
@@ -458,6 +450,7 @@ char* DNS::dns_getresult_s(const int cfd, char *res) { /* retrieve result of DNS
                c = c->next;
        }
        if (c == NULL) {
+               log(DEBUG,"DNS: got a response for a query we didnt send with fd=%d",cfd);
                return NULL; /* query not found */
        }
        /* query found-- pull from list: */
@@ -474,22 +467,27 @@ char* DNS::dns_getresult_s(const int cfd, char *res) { /* retrieve result of DNS
        }
        dns_fill_header(&h,buffer,l - 12);
        if (c->id[0] != h.id[0] || c->id[1] != h.id[1]) {
+               log(DEBUG,"DNS: id mismatch on query");
                delete c;
                return NULL; /* ID mismatch */
        }
        if ((h.flags1 & FLAGS1_MASK_QR) == 0) {
+               log(DEBUG,"DNS: didnt get a query result");
                delete c;
                return NULL;
        }
        if ((h.flags1 & FLAGS1_MASK_OPCODE) != 0) {
+               log(DEBUG,"DNS: got an OPCODE and didnt want one");
                delete c;
                return NULL;
        }
        if ((h.flags2 & FLAGS2_MASK_RCODE) != 0) {
+               log(DEBUG,"DNS lookup failed due to SERVFAIL");
                delete c;
                return NULL;
        }
        if (h.ancount < 1)  { /* no sense going on if we don't have any answers */
+               log(DEBUG,"DNS: no answers!");
                delete c;
                return NULL;
        }
@@ -552,6 +550,7 @@ char* DNS::dns_getresult_s(const int cfd, char *res) { /* retrieve result of DNS
 
        switch (rr.type) {
                case DNS_QRY_PTR:
+                       log(DEBUG,"DNS: got a result of type DNS_QRY_PTR");
                        o = 0;
                        q = 0;
                        while (q == 0 && i < l && o + 256 < 1023) {
@@ -574,6 +573,7 @@ char* DNS::dns_getresult_s(const int cfd, char *res) { /* retrieve result of DNS
                        res[o] = '\0';
                        break;
                case DNS_QRY_A:
+                       log(DEBUG,"DNS: got a result of type DNS_QRY_A");
                        if (c->want_list) {
                                dns_ip4list *alist = (dns_ip4list *) res; /* we have to trust that this is aligned */
                                while ((char *)alist - (char *)res < 700) {
@@ -622,6 +622,7 @@ char* DNS::dns_getresult_s(const int cfd, char *res) { /* retrieve result of DNS
                        break;
                default:
                defaultcase:
+                       log(DEBUG,"DNS: doing something with result 'default'");
                        memcpy(res,&h.payload[i],rr.rdlength);
                        res[rr.rdlength] = '\0';
                        break;
@@ -633,16 +634,19 @@ char* DNS::dns_getresult_s(const int cfd, char *res) { /* retrieve result of DNS
 DNS::DNS()
 {
        dns_init();
+       log(DEBUG,"Create blank DNS");
 }
 
 DNS::DNS(std::string dnsserver)
 {
        dns_init_2(dnsserver.c_str());
+       log(DEBUG,"Create DNS");
 }
 
 void DNS::SetNS(std::string dnsserver)
 {
        dns_init_2(dnsserver.c_str());
+       log(DEBUG,"Set NS");
 }
 
 DNS::~DNS()
@@ -651,57 +655,80 @@ DNS::~DNS()
 
 bool DNS::ReverseLookup(std::string ip)
 {
-       statsDns++;
+       ServerInstance->stats->statsDns++;
         binip = dns_aton4(ip.c_str());
         if (binip == NULL) {
                 return false;
         }
 
-        this->fd = dns_getname4(binip);
-       if (this->fd == -1)
+        this->myfd = dns_getname4(binip);
+       if (this->myfd == -1)
        {
                return false;
        }
+       log(DEBUG,"DNS: ReverseLookup, fd=%d",this->myfd);
+#ifndef THREADED_DNS
+       ServerInstance->SE->AddFd(this->myfd,true,X_ESTAB_DNS);
+#endif
        return true;
 }
 
 bool DNS::ForwardLookup(std::string host)
 {
-       statsDns++;
-       this->fd = dns_getip4(host.c_str());
-       if (this->fd == -1)
+       ServerInstance->stats->statsDns++;
+       this->myfd = dns_getip4(host.c_str());
+       if (this->myfd == -1)
        {
                return false;
        }
+       log(DEBUG,"DNS: ForwardLookup, fd=%d",this->myfd);
+#ifndef THREADED_DNS
+       ServerInstance->SE->AddFd(this->myfd,true,X_ESTAB_DNS);
+#endif
        return true;
 }
 
+bool DNS::HasResult(int fd)
+{
+       return (fd == this->myfd);
+}
+
+/* Only the multithreaded dns uses this poll() based
+ * check now. As its in another thread we dont have
+ * to worry about its performance that much.
+ */
 bool DNS::HasResult()
 {
+       log(DEBUG,"DNS: HasResult, fd=%d",this->myfd);
        pollfd polls;
-       polls.fd = this->fd;
+       polls.fd = this->myfd;
        polls.events = POLLIN;
        int ret = poll(&polls,1,1);
+       log(DEBUG,"DNS: Hasresult returning %d",ret);
        return (ret > 0);
 }
 
 int DNS::GetFD()
 {
-       return this->fd;
+       return this->myfd;
 }
 
 std::string DNS::GetResult()
 {
-        result = dns_getresult(this->fd);
+       log(DEBUG,"DNS: GetResult()");
+        result = dns_getresult(this->myfd);
+#ifndef THREADED_DNS
+       ServerInstance->SE->DelFd(this->myfd);
+#endif
         if (result) {
-               statsDnsGood++;
-               dns_close(this->fd);
+               ServerInstance->stats->statsDnsGood++;
+               dns_close(this->myfd);
                return result;
         } else {
-               statsDnsBad++;
-               if (this->fd != -1)
+               ServerInstance->stats->statsDnsBad++;
+               if (this->myfd != -1)
                {
-                       dns_close(this->fd);
+                       dns_close(this->myfd);
                }
                return "";
        }
@@ -710,19 +737,72 @@ std::string DNS::GetResult()
 std::string DNS::GetResultIP()
 {
        char r[1024];
-       result = dns_getresult(this->fd);
-       if (this->fd != -1)
+       log(DEBUG,"DNS: GetResultIP()");
+       result = dns_getresult(this->myfd);
+       if (this->myfd != -1)
        {
-               dns_close(this->fd);
+#ifndef THREADED_DNS
+               ServerInstance->SE->DelFd(this->myfd);
+#endif
+               dns_close(this->myfd);
        }
        if (result)
        {
-               sprintf(r,"%d.%d.%d.%d",result[0],result[1],result[2],result[3]);
+               ServerInstance->stats->statsDnsGood++;
+               unsigned char a = (unsigned)result[0];
+               unsigned char b = (unsigned)result[1];
+               unsigned char c = (unsigned)result[2];
+               unsigned char d = (unsigned)result[3];
+               snprintf(r,1024,"%u.%u.%u.%u",a,b,c,d);
                return r;
        }
        else
        {
+               ServerInstance->stats->statsDnsBad++;
                log(DEBUG,"DANGER WILL ROBINSON! NXDOMAIN for forward lookup, but we got a reverse lookup!");
                return "";
        }
 }
+
+
+
+#ifdef THREADED_DNS
+void* dns_task(void* arg)
+{
+        userrec* u = (userrec*)arg;
+        log(DEBUG,"DNS thread for user %s",u->nick);
+        DNS dns1;
+        DNS dns2;
+        std::string host;
+        std::string ip;
+        if (dns1.ReverseLookup(u->ip))
+        {
+                while (!dns1.HasResult())
+                {
+                        usleep(100);
+                }
+                host = dns1.GetResult();
+                if (host != "")
+                {
+                        if (dns2.ForwardLookup(host))
+                        {
+                                while (!dns2.HasResult())
+                                {
+                                        usleep(100);
+                                }
+                                ip = dns2.GetResultIP();
+                                if (ip == std::string(u->ip))
+                                {
+                                        if (host.length() < 160)
+                                        {
+                                                strcpy(u->host,host.c_str());
+                                                strcpy(u->dhost,host.c_str());
+                                        }
+                                }
+                        }
+                }
+        }
+        u->dns_done = true;
+        return NULL;
+}
+#endif