Added upstream server support

src/dns_header.cpp

@@ -75,7 +75,9 @@ DnsHeader& DnsHeader::operator=(const DnsHeader& h)
 
 string DnsHeader::data() const
 {
-    string out = "";
+    string out;
+
+    out.clear();
 
     out += string((char*)&_txid, 2);
     out += string((char*)&_flags, 2);

src/dns_packet.cpp

@@ -73,27 +73,24 @@ DnsPacket& DnsPacket::operator=(const DnsPacket& p)
     _fuzzSrcIp = p._fuzzSrcIp;
     _fuzzSport = p._fuzzSport;
     _log = p._log;
+    _spoofing = p._spoofing;
 
     return *this;
 }
 
 string DnsPacket::data() const
 {
-    string out = "";
+    string out = _dnsHdr.data();
 
-    out += _dnsHdr.data();
-
-    if (!_question.empty())
+    if (!_question.empty()) {
         out += _question.data();
-
+    }
     for (vector<ResourceRecord>::const_iterator itr = _answers.begin();
             itr != _answers.end(); ++itr)
         out += itr->data();
-
     for (vector<ResourceRecord>::const_iterator itr = _authorities.begin();
             itr != _authorities.end(); ++itr)
         out += itr->data();
-
     for (vector<ResourceRecord>::const_iterator itr = _additionals.begin();
             itr != _additionals.end(); ++itr)
         out += itr->data();
@@ -273,10 +270,11 @@ void DnsPacket::_socketCreateUdp()
         BASIC_EXCEPTION_THROW("setsockopt");
 }
 
-void DnsPacket::sendNet(bool doCksum)
+DnsPacket* DnsPacket::sendNet(bool doCksum)
 {
     int ret;
     string api;
+    DnsPacket* p = NULL;
 
     // the remote/source sockaddr is put here
     struct sockaddr_in peeraddr;
@@ -327,7 +325,7 @@ void DnsPacket::sendNet(bool doCksum)
 
     // When not spoofing we have to get the packet back
     if (!_spoofing) {
-        DnsPacket p;
+        p = new DnsPacket();
 
         // Control buffer
         char cmbuf[0x100];
@@ -347,10 +345,10 @@ void DnsPacket::sendNet(bool doCksum)
             BASIC_EXCEPTION_THROW("recvmsg");
 
         // Parse the packet into a DnsPacket
-        p.parse((char*)mh.msg_iov[0].iov_base);
-        p.ipFrom(peeraddr.sin_addr.s_addr);
-        p.sport(ntohs(peeraddr.sin_port));
-        p.dport(ntohs(_udpHdr.source));
+        p->parse((char*)mh.msg_iov[0].iov_base);
+        p->ipFrom(peeraddr.sin_addr.s_addr);
+        p->sport(ntohs(peeraddr.sin_port));
+        p->dport(ntohs(_udpHdr.source));
 
         // Get a control buffer and get destination ip from it
         for (struct cmsghdr *cmsg = CMSG_FIRSTHDR(&mh); cmsg != NULL; cmsg = CMSG_NXTHDR(&mh, cmsg)) {
@@ -359,16 +357,18 @@ void DnsPacket::sendNet(bool doCksum)
                 continue;
             }
             struct in_pktinfo *pi = (struct in_pktinfo*)CMSG_DATA(cmsg);
-            p.ipTo(pi->ipi_spec_dst.s_addr);
+            p->ipTo(pi->ipi_spec_dst.s_addr);
         }
 
         // Print the result
         if (_log)
-            _log(string("Received ") + p.to_string());
+            _log(string("Received ") + p->to_string());
 
         free(iov[0].iov_base);
     }
     _packets--;
+
+    return p;
 }
 
 string DnsPacket::ipFrom() const
@@ -401,6 +401,17 @@ string DnsPacket::to_string(bool dnsonly) const
     s += "txid: 0x" + Dines::toHex(_dnsHdr.txid());
 
     s += isQuestion() ? " Q " : " R ";
+
+    s += string("NUM=");
+
+    if (_question.empty())
+        s += "0";
+    else
+        s+= "1";
+
+    s += string(",") + std::to_string(_answers.size()) + "," +
+        std::to_string(_authorities.size()) + "," + std::to_string(_additionals.size()) + " ";
+
     if (!_question.empty())
         s += "[Question:" + _question.to_string() + "]";
 
@@ -577,7 +588,6 @@ void DnsPacket::ipTo(string ip_to)
 
 void DnsPacket::ipTo(uint32_t ip)
 {
-    _spoofing = true;
     _ipHdr.daddr = ip;
 }
 
@@ -758,3 +768,17 @@ void DnsPacket::dport(uint16_t dport)
 {
     _udpHdr.dest = htons(dport);
 }
+
+void DnsPacket::clear()
+{
+    _question.clear();
+
+    for (vector<ResourceRecord>::iterator itr = _answers.begin(); itr != _answers.end(); ++itr)
+        itr->clear();
+
+    for (vector<ResourceRecord>::iterator itr = _authorities.begin(); itr != _authorities.end(); ++itr)
+        itr->clear();
+
+    for (vector<ResourceRecord>::iterator itr = _additionals.begin(); itr != _additionals.end(); ++itr)
+        itr->clear();
+}

src/dns_packet.hpp

@@ -81,7 +81,7 @@ class DnsPacket {
     std::string data() const;
 
     //! Sends the packet into the network
-    void sendNet(bool doCksum = true);
+    DnsPacket* sendNet(bool doCksum = true);
 
     //! to_string
     std::string to_string(bool dnsonly = false) const;
@@ -187,6 +187,9 @@ class DnsPacket {
 
     //! Parse a message from a buffer. The buffer must point to the start of the dns packet
     void parse(char* buf);
+
+    //! Clear the packet
+    void clear();
 };
 
 

src/dns_question.cpp

@@ -12,22 +12,22 @@ using namespace std;
 
 DnsQuestion::DnsQuestion(const string qdomain, const string qtype, const string qclass)
 {
-    _fuzzQtype = false;
-    _fuzzQclass = false;
-
     *this = DnsQuestion(qdomain, Dines::stringToQtype(qtype), Dines::stringToQclass(qclass));
 
     if (qtype == "F") {
-        this->fuzzQtype();
+        this->fuzzQtype(true);
     }
 
     if (qclass == "F") {
-        this->fuzzQclass();
+        this->fuzzQclass(true);
     }
 }
 
 DnsQuestion::DnsQuestion(const string qdomain, uint16_t qtype, uint16_t qclass)
 {
+    _fuzzQtype = false;
+    _fuzzQclass = false;
+
     // Domain
     if (qdomain.size() > 0 && qdomain.at(0) == 'F') {
         unsigned len;
@@ -152,28 +152,39 @@ void DnsQuestion::fuzzQdomain(unsigned len)
     this->fuzz();
 }
 
-void DnsQuestion::fuzzQtype()
+void DnsQuestion::fuzzQtype(bool fuzz)
 {
-    _fuzzQtype = true;
+    _fuzzQtype = fuzz;
     this->fuzz();
 }
 
-void DnsQuestion::fuzzQclass()
+bool DnsQuestion::fuzzQtype() const
+{
+    return _fuzzQtype;
+}
+
+bool DnsQuestion::fuzzQclass() const
 {
-    _fuzzQclass = true;
+    return _fuzzQclass;
+}
+
+void DnsQuestion::fuzzQclass(bool fuzz)
+{
+    _fuzzQclass = fuzz;
     this->fuzz();
 }
 
 string DnsQuestion::to_string() const
 {
-
     return _qdomain_str + "/" + qtypeStr() + "/" + qclassStr();
 }
 
 size_t DnsQuestion::parse(char* buf, unsigned offset)
 {
     unsigned i;
 
+    this->clear();
+
     i = Dines::domainDecode(buf, offset, _qdomain_enc, _qdomain_str);
 
     memcpy(&_qtype, buf + offset + i, 2);
@@ -193,3 +204,11 @@ void DnsQuestion::logger(Dines::LogFunc l)
 {
     _log = l;
 }
+
+void DnsQuestion::clear()
+{
+    _qdomain_enc.clear();
+    _qdomain_str.clear();
+    _qtype = 1;
+    _qclass = 1;
+}

src/dns_question.hpp

@@ -45,8 +45,11 @@ class DnsQuestion {
     DnsQuestion& fuzz();
 
     void fuzzQdomain(unsigned len);
-    void fuzzQtype();
-    void fuzzQclass();
+    bool fuzzQdomain() const;
+    void fuzzQtype(bool fuzz);
+    bool fuzzQtype() const;
+    void fuzzQclass(bool fuzz);
+    bool fuzzQclass() const;
 
     std::string to_string() const;
 
@@ -56,6 +59,8 @@ class DnsQuestion {
 
     //! Set the logger
     void logger(Dines::LogFunc l);
+
+    void clear();
 };
 
 #endif

src/main.cpp

@@ -33,6 +33,7 @@ struct option opts[] = {
     {"auth", 1, NULL, 10},
     {"num-add", 1, NULL, 11},
     {"additional", 1, NULL, 12},
+    {"upstream", 1, NULL, 13},
     // some space here for new params
     {"no-rd", 0, NULL, 28},
     {"server", 2, NULL, 29},
@@ -117,6 +118,7 @@ int main(int argc, char* argv[])
     ResourceRecord rr;
     unsigned temp;
     vector<string> tokens;
+    uint32_t upstream = 0;
 
     cout << "\nDines " << PACKAGE_VERSION << " - The definitive DNS packet forger.\n\n";
 
@@ -179,8 +181,8 @@ int main(int argc, char* argv[])
                     tokens.clear();
                     tokens = tokenize(optarg, ",");
                     tokens.resize(3);
-                    p.addQuestion(tokens.at(0), tokens.at(1), tokens.at(2));
 
+                    p.addQuestion(tokens.at(0), tokens.at(1), tokens.at(2));
                     break;
 
                 case 8: // answer
@@ -236,6 +238,10 @@ int main(int argc, char* argv[])
                     }
                     break;
 
+                case 13: // upstream
+                    upstream = Dines::stringToIp32(optarg);
+                    break;
+
                 case 28: // no-rd
                     p.isRecursive(false);
                     break;
@@ -300,7 +306,17 @@ int main(int argc, char* argv[])
                 return 1;
             }
 
-            Server server(&p, server_port);
+            Server server(p, server_port);
+
+            if (upstream > 0)
+                server.upstream(upstream);
+
+            if (server.invalid()) {
+                cerr << "Invalid parameters:\n\n";
+                cerr << server.invalidMsg() << endl;
+                return 1;
+            }
+
             if (verbose == true)
                 server.logger(logger);
             server.launch();
@@ -333,7 +349,7 @@ int main(int argc, char* argv[])
                 if (p.packets() > 0)
                     nanosleep(&delay, NULL);
             }
-            cout << endl;
+            cout << "\n";
         }
 #ifndef DEBUG
     } catch(exception& e) {

src/rr.cpp

@@ -107,10 +107,11 @@ ResourceRecord& ResourceRecord::operator=(const ResourceRecord& rr)
 
 string ResourceRecord::data() const
 {
-    string out = "";
-
+    string out;
     uint16_t size;
 
+    out.clear();
+
     out += _rrDomain_enc;
     out += string((char*)&_rrType, 2);
     out += string((char*)&_rrClass, 2);
@@ -243,7 +244,7 @@ void ResourceRecord::rrDomain(string domain)
 
 string ResourceRecord::to_string() const
 {
-    string out = "";
+    string out;
 
     out = _rrDomain_str + "/" + this->rrTypeStr() + "/" + this->rrClassStr() + "/" +
         std::to_string(this->ttl());
@@ -268,6 +269,9 @@ size_t ResourceRecord::parse(char* buf, unsigned offset)
     unsigned len;
     unsigned i;
 
+    _rrDomain_enc.clear();
+    _rrDomain_str.clear();
+
     i = Dines::domainDecode(buf, offset, _rrDomain_enc, _rrDomain_str);
 
     memcpy(&_rrType, buf + offset + i, 2);
@@ -278,3 +282,13 @@ size_t ResourceRecord::parse(char* buf, unsigned offset)
     _rData = string(buf + offset + i + 10, len);
     return (i + 10 + len);
 }
+
+void ResourceRecord::clear()
+{
+    _rrDomain_enc.clear();
+    _rrDomain_str.clear();
+    _rrType = 1;
+    _rrClass = 1;
+    _ttl = 0;
+    _rData.clear();
+}