make DNSMessageWriter variable length
This commit is contained in:
bert hubert
parent
62b880018c
commit
294e72b261
@ -4,7 +4,7 @@
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# teaching DNS
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Welcome to tdns, the teaching authoritative server, implementing all of
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basic DNS in 1000 lines of code.
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basic DNS in ~~1000~~ 1100 lines of code.
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The goals of tdns are:
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@ -25,9 +25,9 @@ Features are complete:
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* Wildcards
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* Delegations
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* Glue records
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* Truncation
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Missing:
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* Truncation
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* Compression (may not fit in the 1000 lines!)
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* EDNS (not 'basic' DNS by our definition, but ok)
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@ -7,14 +7,15 @@ void loadZones(DNSNode& zones)
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auto newzone = zone->zone = new DNSNode(); // XXX ICK
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newzone->addRRs(SOAGen::make({"ns1", "powerdns", "org"}, {"admin", "powerdns", "org"}, 1));
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newzone->rrsets[DNSType::MX].add(MXGen::make(25, {"server1", "powerdns", "org"}));
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newzone->addRRs(MXGen::make(25, {"server1", "powerdns", "org"}));
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newzone->rrsets[DNSType::A].add(AGen::make("1.2.3.4"));
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newzone->rrsets[DNSType::AAAA].add(AAAAGen::make("::1"));
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newzone->addRRs(AGen::make("1.2.3.4"));
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newzone->addRRs(AAAAGen::make("::1"));
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newzone->rrsets[DNSType::AAAA].ttl= 900;
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newzone->rrsets[DNSType::NS].add(NSGen::make({"ns1", "powerdns", "org"}));
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newzone->addRRs(TXTGen::make("Proudly served by tdns " __DATE__ " " __TIME__));
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newzone->addRRs(NSGen::make({"ns1", "powerdns", "org"}), NSGen::make({"ns2", "powerdns", "org"}));
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newzone->addRRs(TXTGen::make("Proudly served by tdns compiled on " __DATE__ " " __TIME__),
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TXTGen::make("This is some more filler to make this packet exceed 512 bytes"));
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newzone->add({"www"})->rrsets[DNSType::CNAME].add(CNAMEGen::make({"server1","powerdns","org"}));
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newzone->add({"www2"})->rrsets[DNSType::CNAME].add(CNAMEGen::make({"nosuchserver1","powerdns","org"}));
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@ -25,7 +26,7 @@ void loadZones(DNSNode& zones)
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newzone->add({"*", "fr"})->rrsets[DNSType::CNAME].add(CNAMEGen::make({"server2", "powerdns", "org"}));
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newzone->add({"fra"})->addRRs(NSGen::make({"ns1","fra","powerdns","org"}), NSGen::make({"ns1","fra","powerdns","org"}));
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newzone->add({"ns1"})->addRRs(AGen::make("212.13.14.15"));
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newzone->add({"ns1", "fra"})->addRRs(AGen::make("12.13.14.15"));
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newzone->add({"NS2", "fra"})->addRRs(AGen::make("12.13.14.16"), AAAAGen::make("::1"));
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newzone->add({"something"})->addRRs(AAAAGen::make("::1"), AGen::make("12.13.14.15"));
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@ -7,7 +7,7 @@ std::unique_ptr<RRGen> AGen::make(const ComboAddress& ca)
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void AGen::toMessage(DNSMessageWriter& dmw)
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{
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dmw.payload.putUInt32(d_ip);
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dmw.putUInt32(d_ip);
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}
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std::unique_ptr<RRGen> AAAAGen::make(const ComboAddress& ca)
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@ -23,39 +23,39 @@ std::unique_ptr<RRGen> AAAAGen::make(const ComboAddress& ca)
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void AAAAGen::toMessage(DNSMessageWriter& dmw)
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{
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dmw.payload.putBlob(d_ip, 16);
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dmw.putBlob(d_ip, 16);
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}
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void SOAGen::toMessage(DNSMessageWriter& dmw)
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{
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putName(dmw.payload, d_mname); putName(dmw.payload, d_rname);
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dmw.payload.putUInt32(d_serial); dmw.payload.putUInt32(d_refresh);
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dmw.payload.putUInt32(d_retry); dmw.payload.putUInt32(d_expire);
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dmw.payload.putUInt32(d_minimum);
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dmw.putName(d_mname); dmw.putName(d_rname);
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dmw.putUInt32(d_serial); dmw.putUInt32(d_refresh);
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dmw.putUInt32(d_retry); dmw.putUInt32(d_expire);
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dmw.putUInt32(d_minimum);
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}
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void CNAMEGen::toMessage(DNSMessageWriter& dmw)
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{
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putName(dmw.payload, d_name);
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dmw.putName(d_name);
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}
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void NSGen::toMessage(DNSMessageWriter& dmw)
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{
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putName(dmw.payload, d_name);
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dmw.putName(d_name);
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}
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void MXGen::toMessage(DNSMessageWriter& dmw)
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{
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dmw.payload.putUInt16(d_prio);
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putName(dmw.payload, d_name);
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dmw.putUInt16(d_prio);
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dmw.putName(d_name);
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}
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void TXTGen::toMessage(DNSMessageWriter& dmw)
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{
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// XXX should autosplit
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dmw.payload.putUInt8(d_txt.length());
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dmw.payload.putBlob(d_txt);
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dmw.putUInt8(d_txt.length());
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dmw.putBlob(d_txt);
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}
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void ClockTXTGen::toMessage(DNSMessageWriter& dmw)
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@ -70,6 +70,6 @@ void ClockTXTGen::toMessage(DNSMessageWriter& dmw)
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else
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txt="Overflow";
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// XXX should autosplit
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dmw.payload.putUInt8(txt.length());
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dmw.payload.putBlob(txt);
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dmw.putUInt8(txt.length());
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dmw.putBlob(txt);
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}
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@ -27,17 +27,17 @@ void DNSMessageReader::getQuestion(dnsname& name, DNSType& type)
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void DNSMessageWriter::putRR(DNSSection section, const dnsname& name, DNSType type, uint32_t ttl, const std::unique_ptr<RRGen>& content)
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{
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auto cursize = payload.payloadpos;
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auto cursize = payloadpos;
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try {
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putName(payload, name);
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payload.putUInt16((int)type); payload.putUInt16(1);
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payload.putUInt32(ttl);
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auto pos = payload.putUInt16(0); // placeholder
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putName(name);
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putUInt16((int)type); putUInt16(1);
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putUInt32(ttl);
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auto pos = putUInt16(0); // placeholder
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content->toMessage(*this);
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payload.putUInt16At(pos, payload.payloadpos-pos-2);
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putUInt16At(pos, payloadpos-pos-2);
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}
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catch(...) {
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payload.payloadpos = cursize;
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payloadpos = cursize;
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throw;
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}
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switch(section) {
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@ -58,10 +58,10 @@ void DNSMessageWriter::putRR(DNSSection section, const dnsname& name, DNSType ty
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void DNSMessageWriter::setQuestion(const dnsname& name, DNSType type)
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{
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dh.ancount = dh.arcount = dh.nscount = 0;
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payload.rewind();
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putName(payload, name);
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payload.putUInt16((uint16_t)type);
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payload.putUInt16(1); // class
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payloadpos=0;
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putName(name);
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putUInt16((uint16_t)type);
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putUInt16(1); // class
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}
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string DNSMessageReader::serialize() const
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@ -70,7 +70,9 @@ string DNSMessageReader::serialize() const
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}
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string DNSMessageWriter::serialize() const
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{
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return string((const char*)this, (const char*)this + sizeof(dnsheader) + payload.payloadpos);
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std::string ret((const char*)this, (const char*)this + sizeof(dnsheader));
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ret.append((const unsigned char*)&payload[0], (const unsigned char*)&payload[payloadpos]);
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return ret;
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}
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static_assert(sizeof(DNSMessageReader) == 516, "dnsmessagereader size must be 516");
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@ -2,6 +2,7 @@
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#include "dns.hh"
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#include "safearray.hh"
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#include "dns-storage.hh"
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#include <vector>
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struct DNSMessageReader
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{
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@ -16,20 +17,63 @@ struct DNSMessageReader
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struct DNSMessageWriter
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{
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explicit DNSMessageWriter(int maxsize=512)
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{
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payload.resize(maxsize);
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}
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struct dnsheader dh=dnsheader{};
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SafeArray<1500> payload;
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std::vector<uint8_t> payload;
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void setQuestion(const dnsname& name, DNSType type);
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void putRR(DNSSection section, const dnsname& name, DNSType type, uint32_t ttl, const std::unique_ptr<RRGen>& rr);
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std::string serialize() const;
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uint16_t payloadpos=0;
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void putUInt8(uint8_t val)
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{
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payload.at(payloadpos++)=val;
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}
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uint16_t putUInt16(uint16_t val)
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{
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val = htons(val);
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memcpy(&payload.at(payloadpos+2)-2, &val, 2);
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payloadpos+=2;
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return payloadpos - 2;
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}
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void putUInt16At(uint16_t pos, uint16_t val)
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{
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val = htons(val);
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memcpy(&payload.at(pos+2)-2, &val, 2);
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}
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void putUInt32(uint32_t val)
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{
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val = htonl(val);
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memcpy(&payload.at(payloadpos+sizeof(val)) - sizeof(val), &val, sizeof(val));
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payloadpos += sizeof(val);
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}
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void putBlob(const std::string& blob)
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{
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memcpy(&payload.at(payloadpos+blob.size()) - blob.size(), blob.c_str(), blob.size());
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payloadpos += blob.size();;
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}
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void putBlob(const unsigned char* blob, int size)
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{
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memcpy(&payload.at(payloadpos+size) - size, blob, size);
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payloadpos += size;
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}
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void putName(const dnsname& name)
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{
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for(const auto& l : name) {
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putUInt8(l.size());
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putBlob(l.d_s);
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}
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putUInt8(0);
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}
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};
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inline void putName(SafeArray<1500>& payload, const dnsname& name)
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{
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for(const auto& l : name) {
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if(l.size() > 63)
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throw std::runtime_error("Can't emit a label larger than 63 characters");
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payload.putUInt8(l.size());
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payload.putBlob(l.d_s);
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}
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payload.putUInt8(0);
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}
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@ -27,46 +27,8 @@ struct SafeArray
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memcpy(&ret, &payload.at(payloadpos+2)-2, 2);
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payloadpos+=2;
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return htons(ret);
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}
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void putUInt8(uint8_t val)
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{
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payload.at(payloadpos++)=val;
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}
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uint16_t putUInt16(uint16_t val)
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{
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val = htons(val);
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memcpy(&payload.at(payloadpos+2)-2, &val, 2);
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payloadpos+=2;
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return payloadpos - 2;
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}
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void putUInt16At(uint16_t pos, uint16_t val)
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{
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val = htons(val);
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memcpy(&payload.at(pos+2)-2, &val, 2);
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}
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void putUInt32(uint32_t val)
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{
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val = htonl(val);
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memcpy(&payload.at(payloadpos+sizeof(val)) - sizeof(val), &val, sizeof(val));
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payloadpos += sizeof(val);
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}
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void putBlob(const std::string& blob)
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{
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memcpy(&payload.at(payloadpos+blob.size()) - blob.size(), blob.c_str(), blob.size());
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payloadpos += blob.size();;
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}
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void putBlob(const unsigned char* blob, int size)
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{
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memcpy(&payload.at(payloadpos+size) - size, blob, size);
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payloadpos += size;
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}
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std::string getBlob(int size)
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{
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242
tdns/tdns.cc
242
tdns/tdns.cc
@ -19,13 +19,12 @@ using namespace std;
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void addAdditional(const DNSNode* bestzone, const dnsname& zone, const vector<dnsname>& toresolve, DNSMessageWriter& response)
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{
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for(auto addname : toresolve ) {
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cout<<"Doing additional or glue lookup for "<<addname<<endl;
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cout<<"Doing additional or glue lookup for "<<addname<<" in "<<zone<<endl;
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if(!addname.makeRelative(zone)) {
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cout<<addname<<" is not within our zone, not doing glue"<<endl;
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continue;
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}
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dnsname wuh;
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cout<<"Looking up glue record "<<addname<<" in zone "<<zone<<endl;
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auto addnode = bestzone->find(addname, wuh);
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if(!addnode || !addname.empty()) {
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cout<<" Found nothing, continuing"<<endl;
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@ -44,136 +43,144 @@ void addAdditional(const DNSNode* bestzone, const dnsname& zone, const vector<dn
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}
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bool processQuestion(const DNSNode& zones, DNSMessageReader& dm, const ComboAddress& local, const ComboAddress& remote, DNSMessageWriter& response)
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try
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{
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dnsname name;
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dnsname name, origname;
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DNSType type;
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dm.getQuestion(name, type);
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origname=name; // we munch on this below
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cout<<"Received a query from "<<remote.toStringWithPort()<<" for "<<name<<" and type "<<type<<endl;
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response.dh = dm.dh;
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response.dh.ad = response.dh.ra = response.dh.aa = 0;
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response.dh.qr = 1;
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response.setQuestion(name, type);
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if(type == DNSType::AXFR || type == DNSType::IXFR) {
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cout<<"Query was for AXFR or IXFR over UDP, can't do that"<<endl;
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response.dh.rcode = (int)RCode::Servfail;
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return true;
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}
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if(dm.dh.opcode != 0) {
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cout<<"Query had non-zero opcode "<<dm.dh.opcode<<", sending NOTIMP"<<endl;
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response.dh.rcode = (int)RCode::Notimp;
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return true;
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}
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try {
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response.dh = dm.dh;
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response.dh.ad = response.dh.ra = response.dh.aa = 0;
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response.dh.qr = 1;
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response.setQuestion(name, type);
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dnsname zone;
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auto fnd = zones.find(name, zone);
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if(fnd && fnd->zone) {
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cout<<"---\nBest zone: "<<zone<<", name now "<<name<<", loaded: "<<(void*)fnd->zone<<endl;
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response.dh.aa = 1;
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auto bestzone = fnd->zone;
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dnsname searchname(name), lastnode, zonecutname;
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const DNSNode* passedZonecut=0;
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int CNAMELoopCount = 0;
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loopCNAME:;
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lastnode.clear();
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zonecutname.clear();
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auto node = bestzone->find(searchname, lastnode, &passedZonecut, &zonecutname);
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if(!node) {
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cout<<"Found nothing in zone '"<<zone<<"' for lhs '"<<name<<"'"<<endl;
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if(type == DNSType::AXFR || type == DNSType::IXFR) {
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cout<<"Query was for AXFR or IXFR over UDP, can't do that"<<endl;
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response.dh.rcode = (int)RCode::Servfail;
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return true;
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}
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else if(passedZonecut) {
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response.dh.aa = false;
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cout<<"This is a delegation, zonecutname: '"<<zonecutname<<"'"<<endl;
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for(const auto& rr: passedZonecut->rrsets) {
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cout<<" Have type "<<rr.first<<endl;
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if(dm.dh.opcode != 0) {
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cout<<"Query had non-zero opcode "<<dm.dh.opcode<<", sending NOTIMP"<<endl;
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response.dh.rcode = (int)RCode::Notimp;
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return true;
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}
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dnsname zone;
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auto fnd = zones.find(name, zone);
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if(fnd && fnd->zone) {
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cout<<"---\nBest zone: "<<zone<<", name now "<<name<<", loaded: "<<(void*)fnd->zone<<endl;
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response.dh.aa = 1;
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auto bestzone = fnd->zone;
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dnsname searchname(name), lastnode, zonecutname;
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const DNSNode* passedZonecut=0;
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int CNAMELoopCount = 0;
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loopCNAME:;
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auto node = bestzone->find(searchname, lastnode, &passedZonecut, &zonecutname);
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if(!node) {
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cout<<"Found nothing in zone '"<<zone<<"' for lhs '"<<name<<"'"<<endl;
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}
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auto iter = passedZonecut->rrsets.find(DNSType::NS);
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if(iter != passedZonecut->rrsets.end()) {
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const auto& rrset = iter->second;
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vector<dnsname> toresolve;
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for(const auto& rr : rrset.contents) {
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response.putRR(DNSSection::Authority, zonecutname+zone, DNSType::NS, rrset.ttl, rr);
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toresolve.push_back(dynamic_cast<NSGen*>(rr.get())->d_name);
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else if(passedZonecut) {
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response.dh.aa = false;
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cout<<"This is a delegation, zonecutname: '"<<zonecutname<<"'"<<endl;
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for(const auto& rr: passedZonecut->rrsets) {
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cout<<" Have type "<<rr.first<<endl;
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}
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addAdditional(bestzone, zone, toresolve, response);
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}
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}
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else if(!searchname.empty()) {
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cout<<"This is an NXDOMAIN situation"<<endl;
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const auto& rrset = fnd->zone->rrsets[DNSType::SOA];
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response.dh.rcode = (int)RCode::Nxdomain;
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response.putRR(DNSSection::Authority, zone, DNSType::SOA, rrset.ttl, rrset.contents[0]);
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}
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else {
|
||||
cout<<"Found something in zone '"<<zone<<"' for lhs '"<<name<<"', searchname now '"<<searchname<<"', lastnode '"<<lastnode<<"', passedZonecut="<<passedZonecut<<endl;
|
||||
|
||||
auto iter = node->rrsets.cbegin();
|
||||
vector<dnsname> additional;
|
||||
if(type == DNSType::ANY) {
|
||||
for(const auto& t : node->rrsets) {
|
||||
const auto& rrset = t.second;
|
||||
auto iter = passedZonecut->rrsets.find(DNSType::NS);
|
||||
if(iter != passedZonecut->rrsets.end()) {
|
||||
const auto& rrset = iter->second;
|
||||
vector<dnsname> toresolve;
|
||||
for(const auto& rr : rrset.contents) {
|
||||
response.putRR(DNSSection::Answer, lastnode+zone, t.first, rrset.ttl, rr);
|
||||
if(t.first == DNSType::MX)
|
||||
additional.push_back(dynamic_cast<MXGen*>(rr.get())->d_name);
|
||||
|
||||
response.putRR(DNSSection::Authority, zonecutname+zone, DNSType::NS, rrset.ttl, rr);
|
||||
toresolve.push_back(dynamic_cast<NSGen*>(rr.get())->d_name);
|
||||
}
|
||||
addAdditional(bestzone, zone, toresolve, response);
|
||||
}
|
||||
}
|
||||
else if(iter = node->rrsets.find(type), iter != node->rrsets.end()) {
|
||||
const auto& rrset = iter->second;
|
||||
for(const auto& rr : rrset.contents) {
|
||||
response.putRR(DNSSection::Answer, lastnode+zone, type, rrset.ttl, rr);
|
||||
if(type == DNSType::MX)
|
||||
additional.push_back(dynamic_cast<MXGen*>(rr.get())->d_name);
|
||||
}
|
||||
|
||||
}
|
||||
else if(iter = node->rrsets.find(DNSType::CNAME), iter != node->rrsets.end()) {
|
||||
cout<<"We do have a CNAME!"<<endl;
|
||||
const auto& rrset = iter->second;
|
||||
dnsname target;
|
||||
for(const auto& rr : rrset.contents) {
|
||||
response.putRR(DNSSection::Answer, lastnode+zone, DNSType::CNAME, rrset.ttl, rr);
|
||||
target=dynamic_cast<CNAMEGen*>(rr.get())->d_name;
|
||||
}
|
||||
if(target.makeRelative(zone)) {
|
||||
cout<<" Should follow CNAME to "<<target<<" within our zone"<<endl;
|
||||
// XXX we need to change our behaviour on NXDOMAIN I think depending on if you've followed a CNAME
|
||||
searchname = target;
|
||||
if(CNAMELoopCount++ < 10)
|
||||
goto loopCNAME;
|
||||
}
|
||||
else
|
||||
cout<<" CNAME points to record "<<target<<" in other zone, good luck"<<endl;
|
||||
else if(!searchname.empty()) {
|
||||
cout<<"This is an NXDOMAIN situation"<<endl;
|
||||
const auto& rrset = fnd->zone->rrsets[DNSType::SOA];
|
||||
response.dh.rcode = (int)RCode::Nxdomain;
|
||||
response.putRR(DNSSection::Authority, zone, DNSType::SOA, rrset.ttl, rrset.contents[0]);
|
||||
}
|
||||
else {
|
||||
cout<<"Node exists, qtype doesn't, NOERROR situation, inserting SOA"<<endl;
|
||||
const auto& rrset = fnd->zone->rrsets[DNSType::SOA];
|
||||
response.putRR(DNSSection::Answer, zone, DNSType::SOA, rrset.ttl, rrset.contents[0]);
|
||||
}
|
||||
addAdditional(bestzone, zone, additional, response);
|
||||
cout<<"Found something in zone '"<<zone<<"' for lhs '"<<name<<"', searchname now '"<<searchname<<"', lastnode '"<<lastnode<<"', passedZonecut="<<passedZonecut<<endl;
|
||||
|
||||
auto iter = node->rrsets.cbegin();
|
||||
vector<dnsname> additional;
|
||||
if(type == DNSType::ANY) {
|
||||
for(const auto& t : node->rrsets) {
|
||||
const auto& rrset = t.second;
|
||||
for(const auto& rr : rrset.contents) {
|
||||
response.putRR(DNSSection::Answer, lastnode+zone, t.first, rrset.ttl, rr);
|
||||
if(t.first == DNSType::MX)
|
||||
additional.push_back(dynamic_cast<MXGen*>(rr.get())->d_name);
|
||||
|
||||
}
|
||||
}
|
||||
}
|
||||
else if(iter = node->rrsets.find(type), iter != node->rrsets.end()) {
|
||||
const auto& rrset = iter->second;
|
||||
for(const auto& rr : rrset.contents) {
|
||||
response.putRR(DNSSection::Answer, lastnode+zone, type, rrset.ttl, rr);
|
||||
if(type == DNSType::MX)
|
||||
additional.push_back(dynamic_cast<MXGen*>(rr.get())->d_name);
|
||||
}
|
||||
|
||||
}
|
||||
else if(iter = node->rrsets.find(DNSType::CNAME), iter != node->rrsets.end()) {
|
||||
cout<<"We do have a CNAME!"<<endl;
|
||||
const auto& rrset = iter->second;
|
||||
dnsname target;
|
||||
for(const auto& rr : rrset.contents) {
|
||||
response.putRR(DNSSection::Answer, lastnode+zone, DNSType::CNAME, rrset.ttl, rr);
|
||||
target=dynamic_cast<CNAMEGen*>(rr.get())->d_name;
|
||||
}
|
||||
if(target.makeRelative(zone)) {
|
||||
cout<<" Should follow CNAME to "<<target<<" within our zone"<<endl;
|
||||
// XXX we need to change our behaviour on NXDOMAIN I think depending on if you've followed a CNAME
|
||||
searchname = target;
|
||||
if(CNAMELoopCount++ < 10) {
|
||||
lastnode.clear();
|
||||
zonecutname.clear();
|
||||
goto loopCNAME;
|
||||
}
|
||||
}
|
||||
else
|
||||
cout<<" CNAME points to record "<<target<<" in other zone, good luck"<<endl;
|
||||
}
|
||||
else {
|
||||
cout<<"Node exists, qtype doesn't, NOERROR situation, inserting SOA"<<endl;
|
||||
const auto& rrset = fnd->zone->rrsets[DNSType::SOA];
|
||||
response.putRR(DNSSection::Answer, zone, DNSType::SOA, rrset.ttl, rrset.contents[0]);
|
||||
}
|
||||
addAdditional(bestzone, zone, additional, response);
|
||||
|
||||
}
|
||||
}
|
||||
else {
|
||||
cout<<"No zone matched"<<endl;
|
||||
response.dh.rcode = (uint8_t)RCode::Refused;
|
||||
}
|
||||
return true;
|
||||
}
|
||||
else {
|
||||
cout<<"No zone matched"<<endl;
|
||||
response.dh.rcode = (uint8_t)RCode::Refused;
|
||||
catch(std::out_of_range& e) { // exceeded packet size
|
||||
cout<<"Query for '"<<origname<<"'|"<<type<<" got truncated"<<endl;
|
||||
response.setQuestion(origname, type); // this resets the packet
|
||||
response.dh.tc=1; response.dh.aa=0;
|
||||
return true;
|
||||
}
|
||||
catch(std::exception& e) {
|
||||
cout<<"Error processing query: "<<e.what()<<endl;
|
||||
return false;
|
||||
}
|
||||
return true;
|
||||
}
|
||||
catch(std::exception& e) {
|
||||
cout<<"Error processing query: "<<e.what()<<endl;
|
||||
return false;
|
||||
}
|
||||
|
||||
void udpThread(ComboAddress local, Socket* sock, const DNSNode* zones)
|
||||
@ -246,7 +253,7 @@ void tcpClientThread(ComboAddress local, ComboAddress remote, int s, const DNSNo
|
||||
dnsname name;
|
||||
DNSType type;
|
||||
dm.getQuestion(name, type);
|
||||
DNSMessageWriter response;
|
||||
DNSMessageWriter response(std::numeric_limits<uint16_t>::max()-sizeof(dnsheader));
|
||||
|
||||
if(type == DNSType::AXFR) {
|
||||
cout<<"Should do AXFR for "<<name<<endl;
|
||||
@ -281,7 +288,7 @@ void tcpClientThread(ComboAddress local, ComboAddress remote, int s, const DNSNo
|
||||
try {
|
||||
response.putRR(DNSSection::Answer, nname, p.first, p.second.ttl, rr);
|
||||
}
|
||||
catch(...) { // exceeded packet size
|
||||
catch(std::out_of_range& e) { // exceeded packet size
|
||||
writeTCPResponse(sock, response);
|
||||
response.setQuestion(zone, type);
|
||||
goto retry;
|
||||
@ -311,14 +318,9 @@ void tcpClientThread(ComboAddress local, ComboAddress remote, int s, const DNSNo
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
int main(int argc, char** argv)
|
||||
try
|
||||
{
|
||||
cout<<sizeof(AGen)<<endl;
|
||||
cout<<sizeof(MXGen)<<endl;
|
||||
cout<<sizeof(RRGen)<<endl;
|
||||
|
||||
if(argc != 2) {
|
||||
cerr<<"Syntax: tdns ipaddress:port"<<endl;
|
||||
return(EXIT_FAILURE);
|
||||
|
||||
Loading…
Reference in New Issue
Block a user