#include <string>
#include <errno.h>
-#include<boost/tokenizer.hpp>
+#include <boost/tokenizer.hpp>
+#include <boost/algorithm/string.hpp>
#include <algorithm>
#include "dns.hh"
#include "dnspacket.hh"
#include "logger.hh"
#include "arguments.hh"
-
+#include "dnswriter.hh"
+#include "dnsparser.hh"
DNSPacket::DNSPacket()
{
return stringbuffer;
}
+const char *DNSPacket::getData(void)
+{
+ if(!d_wrapped)
+ wrapup();
+
+ return stringbuffer.data();
+}
+
+const char *DNSPacket::getRaw(void)
+{
+ return stringbuffer.data();
+}
+
string DNSPacket::getRemote() const
{
return remote.toString();
d=orig.d;
}
-int DNSPacket::expand(const unsigned char *begin, const unsigned char *end, string &expanded, int depth)
-{
- if(depth>10)
- throw AhuException("Looping label when parsing a packet");
-
- unsigned int n;
- const unsigned char *p=begin;
-
- while((n=*(unsigned char *)p++)) {
- char tmp[256];
- if(n==0x41)
- throw AhuException("unable to expand binary label, generally caused by deprecated IPv6 reverse lookups");
-
- if((n & 0xc0) == 0xc0 ) {
- unsigned int labelOffset=(n&~0xc0)*256+ (int)*(unsigned char *)p;
- expand((unsigned char *)stringbuffer.c_str()+labelOffset,end,expanded,++depth); // was cvstrac ticket #21
- return 1+p-begin;
- }
-
- if(p+n>=end) { // this is a bogus packet, references beyond the end of the buffer
- throw AhuException("Label claims to be longer than packet");
- }
- strncpy((char *)tmp,(const char *)p,n);
-
- if(*(p+n)) { // add a ., except at the end
- tmp[n]='.';
- tmp[n+1]=0;
- }
- else
- tmp[n]=0;
-
- expanded+=tmp;
-
- p+=n;
- }
-
- // lowercase(qdomain); (why was this?)
-
- return p-begin;
-}
-
-/** copies the question into our class
- * and returns offset of question type & class. Returns -1 in case of an error
- */
-int DNSPacket::getq()
-{
- const unsigned char *orig=(const unsigned char *)stringbuffer.c_str()+12;
- const unsigned char *end=orig+(stringbuffer.length()-12);
- qdomain="";
- try {
- return expand(orig,end,qdomain);
- }
- catch(AhuException &ae) {
- L<<Logger::Error<<"On retrieving question of packet from "<<getRemote()<<", encountered error: "<<ae.reason<<endl;
- }
- return -1;
-}
-
-/*
- 1 1 1 1 1 1
- 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
- +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- | ID |
- +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- |QR| Opcode |AA|TC|RD|RA| Z | RCODE |
- +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- | QDCOUNT |
- +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- | ANCOUNT |
- +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- | NSCOUNT |
- +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- | ARCOUNT |
- +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
-*/
-
void DNSPacket::setRcode(int v)
{
d.rcode=v;
d.opcode=opcode;
}
-const char *DNSPacket::getRaw(void)
-{
- return stringbuffer.data();
-}
-
-void DNSPacket::addARecord(const DNSResourceRecord &rr)
-{
- DLOG(L<<"Adding an A record to the packet!"<<endl);
- addARecord(rr.qname, htonl(inet_addr(rr.content.c_str())), rr.ttl, rr.d_place);
-}
void DNSPacket::clearRecords()
{
rrs.push_back(rr);
}
-void DNSPacket::addARecord(const string &name, uint32_t ip, uint32_t ttl, DNSResourceRecord::Place place)
-{
- string piece1;
- toqname(name, &piece1);
-
- char p[14];
- makeHeader(p,QType::A,ttl);
- p[8]=0;
- p[9]=4; // length of data
-
- putLong(p+10,ip);
- stringbuffer.append(piece1);
- stringbuffer.append(p,14);
-
- if(place==DNSResourceRecord::ADDITIONAL)
- d.arcount++;
- else
- d.ancount++;
-}
-
-void DNSPacket::addAAAARecord(const DNSResourceRecord &rr)
-{
- DLOG(L<<"Adding an AAAA record to the packet!"<<endl);
- unsigned char addr[16];
-
-#ifdef HAVE_IPV6
- if( Utility::inet_pton( AF_INET6, rr.content.c_str(), static_cast< void * >( addr )))
- addAAAARecord(rr.qname, addr, rr.ttl,rr.d_place);
- else
-#endif
- L<<Logger::Error<<"Unable to convert IPv6 TEXT '"<<rr.content<<"' into binary for record '"<<rr.qname<<"': "
- <<endl;
-}
-
-void DNSPacket::addAAAARecord(const string &name, unsigned char addr[16], uint32_t ttl,DNSResourceRecord::Place place)
-{
- string piece1;
- toqname(name.c_str(),&piece1);
-
- char p[26];
- makeHeader(p,QType::AAAA,ttl);
- p[8]=0;
- p[9]=16; // length of data
-
- for(int n=0;n<16;n++)
- p[10+n]=addr[n];
-
- stringbuffer.append(piece1);
- stringbuffer.append(p,26);
- if(place==DNSResourceRecord::ADDITIONAL)
- d.arcount++;
- else
- d.ancount++;
-}
-
-void DNSPacket::addMXRecord(const DNSResourceRecord &rr)
-{
- addMXRecord(rr.qname, rr.content, rr.priority, rr.ttl);
-}
-
-void DNSPacket::addMXRecord(const string &domain, const string &mx, int priority, uint32_t ttl)
-{
- string piece1;
-
- toqname(domain,&piece1);
-
- char piece2[12];
- makeHeader(piece2,QType::MX,ttl);
-
- // start of payload for which we need to specify the length in 8 & 9
-
- piece2[10]=(priority>>8)&0xff;
- piece2[11]=priority&0xff;
-
- string piece3;
- toqname(mx,&piece3);
- // end of payload
-
- piece2[9]=piece3.length()+2; // fill in length
-
- stringbuffer+=piece1;
- stringbuffer.append(piece2,12);
- stringbuffer+=piece3;
-
- d.ancount++;
-}
-
-
-void DNSPacket::addSRVRecord(const DNSResourceRecord &rr)
-{
- addSRVRecord(rr.qname, rr.content, rr.priority, rr.ttl);
-}
-
-void DNSPacket::addSRVRecord(const string &domain, const string &srv, int priority, uint32_t ttl)
-{
- string piece1;
- toqname(domain,&piece1);
-
- string target;
- int weight=0;
- int port=0;
-
- vector<string>parts;
- stringtok(parts,srv);
- int pleft=parts.size();
-
- // We need to have exactly 3 parts, so we have to check it!
- if (pleft<2) {
- throw AhuException("Missing data for type SRV "+domain);
- }
-
- if(pleft)
- weight = atoi(parts[0].c_str());
-
- if(pleft>1)
- port = atoi(parts[1].c_str());
-
- if(pleft>2)
- toqname(parts[2],&target);
-
-
-
- char p[16];
- makeHeader(p,QType::SRV,ttl);
-
- p[8]=0;
- p[9]=0; // need to fill this in
-
- // start of payload for which we need to specify the length in 8 & 9
-
- // priority aka preference
- p[10]=(priority>>8)&0xff;
- p[11]=priority&0xff;
-
- // weight
- p[12]=(weight>>8)&0xff;
- p[13]=weight&0xff;
-
- // port
- p[14]=(port>>8)&0xff;
- p[15]=port&0xff;
-
- // target
- // end of payload
-
- p[9]=target.length()+6; // fill in length
-
- stringbuffer+=piece1;
- stringbuffer.append(p,16);
- stringbuffer+=target;
-
- d.ancount++;
-}
+// the functions below update the 'arcount' and 'ancount', plus they serialize themselves to the stringbuffer
string& attodot(string &str)
{
if(pleft>4)
data.retry=atoi(parts[4].c_str());
-
if(pleft>5)
data.expire=atoi(parts[5].c_str());
}
-
string serializeSOAData(const SOAData &d)
{
ostringstream o;
return o.str();
}
- /* the hostmaster is encoded as two parts - the bit UNTIL the first unescaped '.'
- is encoded as a TXT string, the rest as a domain
-
- we might encounter escaped dots in the first part though: bert\.hubert.powerdns.com for example should be
- 11bert.hubert7powerdns3com0 */
-
-/* Very ugly btw, this needs to be better */
-const string DNSPacket::makeSoaHostmasterPiece(const string &hostmaster)
-{
- string ret;
- string first;
- string::size_type i;
-
- for(i=0;i<hostmaster.length();++i) {
- if(hostmaster[i]=='.') {
- break;
- }
- if(hostmaster[i]=='\\' && i+1<hostmaster.length()) {
- ++i;
- first.append(1,hostmaster[i]);
- continue;
- }
- first.append(1,hostmaster[i]);
- }
-
- ret.resize(1);
- ret[0]=first.length();
- ret+=first;
-
- string second;
- if(i+1<hostmaster.length())
- toqname(hostmaster.substr(i+1),&second);
- else {
- second.resize(1);
- second[0]=0;
- }
-
- return ret+second;
-}
-
-
-void DNSPacket::addSOARecord(const DNSResourceRecord &rr)
-{
- addSOARecord(rr.qname, rr.content, rr.ttl, rr.d_place);
-}
-
-void DNSPacket::addSOARecord(const string &domain, const string & content, uint32_t ttl,DNSResourceRecord::Place place)
-{
- SOAData soadata;
- fillSOAData(content, soadata);
-
- string piece1;
- toqname(domain, &piece1);
-
- char p[10];
- makeHeader(p,QType::SOA,ttl);
-
- string piece3;
- toqname(soadata.nameserver,&piece3, false);
-
- string piece4=makeSoaHostmasterPiece(soadata.hostmaster);
-
- uint32_t piece5[5];
-
- uint32_t *i_p=piece5;
-
- uint32_t soaoffset=0;
- if(soadata.serial && (soaoffset=arg().asNum("soa-serial-offset")))
- if(soadata.serial<soaoffset)
- soadata.serial+=soaoffset; // thank you DENIC
-
- *i_p++=htonl(soadata.serial ? soadata.serial : time(0));
- *i_p++=htonl(soadata.refresh);
- *i_p++=htonl(soadata.retry);
- *i_p++=htonl(soadata.expire);
- *i_p++=htonl(soadata.default_ttl);
-
- p[9]=piece3.length()+piece4.length()+20;
-
- stringbuffer+=piece1;
- stringbuffer.append(p,10);
- stringbuffer+=piece3;
- stringbuffer+=piece4;
- stringbuffer.append((char*)piece5,20);
- if(place==DNSResourceRecord::ANSWER)
- d.ancount++;
- else
- d.nscount++;
-}
-
-void DNSPacket::addCNAMERecord(const DNSResourceRecord &rr)
-{
- addCNAMERecord(rr.qname, rr.content, rr.ttl);
-}
-
-
-void DNSPacket::addMRRecord(const DNSResourceRecord &rr)
-{
- addMRRecord(rr.qname, rr.content, rr.ttl);
-}
-
-void DNSPacket::addMRRecord(const string& domain, const string& alias, uint32_t ttl)
-{
- string piece1;
-
- toqname(domain.c_str(),&piece1);
- char p[10];
-
- p[0]=0;
- p[1]=QType::MR;
- p[2]=0;
- p[3]=1; // IN
-
- putLong(p+4,ttl);
- p[8]=0;
- p[9]=0; // need to fill this in
-
- string piece3;
- toqname(alias,&piece3);
-
- p[9]=piece3.length();
-
- stringbuffer+=piece1;
- stringbuffer.append(p,10);
- stringbuffer+=piece3;
-
- d.ancount++;
-}
-
-void DNSPacket::addCNAMERecord(const string &domain, const string &alias, uint32_t ttl)
-{
- string piece1;
-
- toqname(domain.c_str(),&piece1);
- char p[10];
-
- p[0]=0;
- p[1]=5; // CNAME
- p[2]=0;
- p[3]=1; // IN
-
- putLong(p+4,ttl);
- p[8]=0;
- p[9]=0; // need to fill this in
-
- string piece3;
- //xtoqname(alias,&piece3);
- toqname(alias,&piece3);
-
- p[9]=piece3.length();
-
- stringbuffer+=piece1;
- stringbuffer.append(p,10);
- stringbuffer+=piece3;
-
- d.ancount++;
-}
-
-
-void DNSPacket::addRPRecord(const DNSResourceRecord &rr)
-{
- addRPRecord(rr.qname, rr.content, rr.ttl);
-}
-
-void DNSPacket::addRPRecord(const string &domain, const string &content, uint32_t ttl)
-{
- string piece1;
-
- toqname(domain.c_str(),&piece1);
- char p[11];
- makeHeader(p,17,ttl);
-
- // content contains: mailbox-name more-info-domain (Separated by a space)
- string::size_type pos;
- if((pos=content.find(" "))==string::npos) {
- L<<Logger::Warning<<"RP record for domain '"<<domain<<"' has malformed content field"<<endl;
- return;
- }
-
- string mboxname=content.substr(0,pos);
- string moreinfo=content.substr(pos+1);
-
- string piece3;
- toqname(mboxname,&piece3);
-
- string piece4;
- toqname(moreinfo,&piece4);
-
- p[9]=(piece3.length()+piece4.length())%256;
- p[10]=(piece3.length()+piece4.length())/256;
-
- stringbuffer+=piece1;
- stringbuffer.append(p,10);
- stringbuffer+=piece3;
- stringbuffer+=piece4;
-
- // done
- d.ancount++;
-}
-
-
-
-
-void DNSPacket::addNAPTRRecord(const DNSResourceRecord &rr)
-{
- addNAPTRRecord(rr.qname, rr.content, rr.ttl);
-}
-
-
-void DNSPacket::makeHeader(char *p,uint16_t qtype, uint32_t ttl)
-{
- p[0]=0;
- p[1]=qtype;
- p[2]=0;
- p[3]=1; // IN
- putLong(p+4,ttl);
- p[8]=0;
- p[9]=0; // need to fill this in
-}
-
-void DNSPacket::addNAPTRRecord(const string &domain, const string &content, uint32_t ttl)
-{
- string piece1;
-
- //xtoqname(domain.c_str(),&piece1);
- toqname(domain.c_str(),&piece1);
- char p[11];
- makeHeader(p,QType::NAPTR,ttl);
-
- // content contains: 100 100 "s" "http+I2R" "" _http._tcp.foo.com.
- // 100 50 "u" "e2u+sip" "" testuser@domain.com
-
- using namespace boost;
- escaped_list_separator<char> els("\\", " ", "\"");
- tokenizer<escaped_list_separator<char> > tok(content, els);
- tokenizer<escaped_list_separator<char> >::iterator iter=tok.begin();
- int order, pref;
- string flags, services, regex, replacement;
- unsigned int n;
- for(n=0; iter != tok.end(); ++iter, ++n) {
- switch(n) {
- case 0:
- order=atoi(iter->c_str());
- break;
- case 1:
- pref=atoi(iter->c_str());
- break;
- case 2:
- flags=*iter;
- break;
- case 3:
- services=*iter;
- break;
- case 4:
- regex=*iter;
- break;
- case 5:
- replacement=*iter;
- break;
- }
- }
- if(n!=6 || iter!=tok.end())
- throw AhuException("Error parsing NAPTR content '"+content+"'");
-
-/*
- The packet format for the NAPTR record is:
-
- 1 1 1 1 1 1
- 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
- +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- | ORDER |
- +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- | PREFERENCE |
- +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- / FLAGS /
- +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- / SERVICES /
- +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- / REGEXP /
- +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- / REPLACEMENT /
- / /
- +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- (jeez)
-*/
-
-
- string piece3;
- piece3.resize(4);
-
- piece3[0]=(order>>8)&0xff;
- piece3[1]=(order)&0xff;
-
- piece3[2]=(pref>>8)&0xff;
- piece3[3]=(pref)&0xff;
-
- piece3.append(1,flags.length());
- piece3.append(flags);
- piece3.append(1,services.length());
- piece3.append(services);
- piece3.append(1,regex.length());
- piece3.append(regex);
-
- string piece4;
- toqname(replacement,&piece4, false); // don't compress
-
- p[9]=(piece3.length()+piece4.length())%256;
- p[10]=(piece3.length()+piece4.length())/256;
-
- stringbuffer+=piece1;
- stringbuffer.append(p,10);
- stringbuffer+=piece3;
- stringbuffer+=piece4;
-
- // done
- d.ancount++;
-}
-
-void DNSPacket::addPTRRecord(const DNSResourceRecord &rr)
-{
- addPTRRecord(rr.qname, rr.content, rr.ttl);
-}
-
-void DNSPacket::addPTRRecord(const string &domain, const string &alias, uint32_t ttl)
-{
- string piece1;
-
- toqname(domain,&piece1);
- char p[10];
- makeHeader(p,QType::PTR,ttl);
-
- string piece3;
- toqname(alias,&piece3);
-
- p[9]=piece3.length();
-
- stringbuffer+=piece1;
- stringbuffer.append(p,10);
- stringbuffer+=piece3;
-
- d.ancount++;
-}
-
-void DNSPacket::addTXTRecord(const DNSResourceRecord& rr)
-{
- addTXTorSPFRecord(QType::TXT, rr.qname, rr.content, rr.ttl);
-}
-
-void DNSPacket::addSPFRecord(const DNSResourceRecord& rr)
-{
- addTXTorSPFRecord(QType::SPF, rr.qname, rr.content, rr.ttl);
-}
-
-
-void DNSPacket::addTXTorSPFRecord(uint16_t qtype, string domain, string txt, uint32_t ttl)
-{
- string piece1;
- //xtoqname(domain, &piece1);
- toqname(domain, &piece1);
- char p[10];
- makeHeader(p, qtype, ttl);
- string piece3;
- piece3.reserve(txt.length()+1);
- piece3.append(1,txt.length());
- piece3.append(txt);
-
- p[8]=piece3.length()/256;;
- p[9]=piece3.length()%256;
-
- stringbuffer+=piece1;
- stringbuffer.append(p,10);
- stringbuffer+=piece3;
-
- d.ancount++;
-}
-void DNSPacket::addHINFORecord(const DNSResourceRecord& rr)
-{
- addHINFORecord(rr.qname, rr.content, rr.ttl);
-}
-
-/** First word of content is the CPU */
-void DNSPacket::addHINFORecord(string domain, string content, uint32_t ttl)
-{
- string piece1;
- toqname(domain, &piece1);
- char p[10];
- makeHeader(p,QType::HINFO,ttl);
-
- string::size_type offset=content.find(" ");
- string cpu, host;
- if(offset==string::npos) {
- cpu=content;
- } else {
- cpu=content.substr(0,offset);
- host=content.substr(offset);
- }
-
- string piece3;
- piece3.reserve(cpu.length()+1);
- piece3.append(1,cpu.length());
- piece3.append(cpu);
-
- string piece4;
- piece4.reserve(host.length()+1);
- piece4.append(1,host.length());
- piece4.append(host);
-
- p[8]=0;
- p[9]=piece3.length()+piece4.length();
-
- stringbuffer+=piece1;
- stringbuffer.append(p,10);
- stringbuffer+=piece3;
- stringbuffer+=piece4;
-
- d.ancount++;
-}
-
-void DNSPacket::addNSRecord(const DNSResourceRecord &rr)
-{
- addNSRecord(rr.qname, rr.content, rr.ttl, rr.d_place);
-}
-
-void DNSPacket::addNSRecord(string domain, string server, uint32_t ttl, DNSResourceRecord::Place place)
-{
- string piece1;
- toqname(domain, &piece1);
-
- char p[10];
- makeHeader(p,QType::NS,ttl);
-
- string piece3;
- string::size_type pos=server.find('@'); // chop off @
- if(pos!=string::npos)
- server.resize(pos);
-
- toqname(server,&piece3);
-
- p[9]=piece3.length();;
-
- stringbuffer.append(piece1);
- stringbuffer.append(p,10);
- stringbuffer.append(piece3);
-
- if(place==DNSResourceRecord::AUTHORITY)
- d.nscount++;
- else
- d.ancount++;
-
-}
-
static int rrcomp(const DNSResourceRecord &A, const DNSResourceRecord &B)
{
return 0;
}
-/** You can call this function to find out if there are any records that need additional processing.
- This holds for MX records and CNAME records, where information about the content may need further resolving. */
-bool DNSPacket::needAP()
-{
- // if speed ever becomes an issue, this function might be implemented in the addRecord() method, which would set a flag
- // whenever a record that needs additional processing is added
-
- for(vector<DNSResourceRecord>::const_iterator i=rrs.begin();
- i!=rrs.end();
- ++i)
- {
- if(i->d_place!=DNSResourceRecord::ADDITIONAL &&
- ( (i->qtype.getCode()==QType::NS && i->content.find('@')==string::npos) || // NS records with @ in them are processed
- i->qtype.getCode()==QType::MX ))
- {
- return true;
- }
- }
- return false;
-}
-
vector<DNSResourceRecord*> DNSPacket::getAPRecords()
{
vector<DNSResourceRecord*> arrs;
}
d_wrapped=true;
+ vector<uint8_t> packet;
+ DNSPacketWriter pw(packet, qdomain, qtype.getCode(), 1);
- for(pos=rrs.begin();pos<rrs.end();++pos) {
- rr=*pos;
- DLOG(L<<"Added to data, RR: " << rr.qname);
- DLOG(L<<"(" << rr.qtype.getName() << ")" << " " << (int) rr.d_place<< endl);
-
- switch(rr.qtype.getCode()) {
- case 1: // A
- addARecord(rr);
- break;
- case 2: // NS
- addNSRecord(rr);
- break;
-
- case 5: // CNAME
- addCNAMERecord(rr);
- break;
-
- case 6: // SOA
- addSOARecord(rr);
- break;
-
- case QType::MR:
- addMRRecord(rr);
- break;
-
- case 12: // PTR
- addPTRRecord(rr);
- break;
-
- case 13: // HINFO
- addHINFORecord(rr);
- break;
-
- case 15: // MX
- addMXRecord(rr);
- break;
-
- case QType::TXT: // TXT
-
- addTXTRecord(rr);
- break;
-
- case 17: // RP
- addRPRecord(rr);
- break;
-
-
- case 28: // AAAA
- addAAAARecord(rr);
- break;
-
- case QType::SRV:
- addSRVRecord(rr);
- break;
-
- case QType::LOC:
- addLOCRecord(rr);
- break;
-
- case QType::NAPTR:
- addNAPTRRecord(rr);
- break;
-
- case QType::SPF: // SPF
- addSPFRecord(rr);
- break;
-
- case 258: // CURL
- case 256: // URL
- addARecord(rr.qname,htonl(inet_addr(arg()["urlredirector"].c_str())),rr.ttl,DNSResourceRecord::ANSWER);
- break;
-
- case 257: // MBOXFW
- string::size_type pos;
- pos=rr.qname.find("@");
- DLOG(L<<Logger::Warning<<"Adding rr.qname: '"<<rr.qname<<"'"<<endl);
- if(pos!=string::npos)
- {
- string substr=rr.qname.substr(pos+1);
-
- addMXRecord(substr,arg()["smtpredirector"],25,rr.ttl);
- }
- break;
+ pw.getHeader()->aa=d.aa;
+ pw.getHeader()->ra=d.ra;
+ pw.getHeader()->qr=d.qr;
+ pw.getHeader()->id=d.id;
+ pw.getHeader()->rd=d.rd;
- default:
- if(rr.qtype.getCode()>1024)
- addGenericRecord(rr);
- else
- L<<Logger::Warning<<"Unable to insert a record of type "<<rr.qtype.getName()<<" for '"<<rr.qname<<"'"<<endl;
+ for(pos=rrs.begin();pos<rrs.end();++pos) {
+ // this needs to deal with the 'prio' mismatch!
+ if(pos->qtype.getCode()==QType::MX || pos->qtype.getCode() == QType::SRV) {
+ pos->content = lexical_cast<string>(pos->priority) + " " + pos->content;
}
+ pw.startRecord(pos->qname, pos->qtype.getCode(), pos->ttl, 1, (DNSPacketWriter::Place)pos->d_place);
+ shared_ptr<DNSRecordContent> drc(DNSRecordContent::mastermake(pos->qtype.getCode(), 1, pos->content));
+ drc->toPacket(pw);
}
- d.ancount=htons(d.ancount);
- d.qdcount=htons(d.qdcount);
- d.nscount=htons(d.nscount);
- d.arcount=htons(d.arcount);
-
- commitD();
-
- len=stringbuffer.length();
+ try {
+ pw.commit();
+ }
+ catch(exception& e) {
+ cerr<<"Exception: "<<e.what()<<endl;
+ throw;
+ }
+ stringbuffer.assign((char*)&packet[0], packet.size());
+ len=packet.size();
}
-void DNSPacket::addGenericRecord(const DNSResourceRecord& rr)
-{
- string piece1;
- //xtoqname(domain, &piece1);
- toqname(rr.qname, &piece1);
- char p[10];
-
- p[0]=0;
- p[1]=rr.qtype.getCode()-1024; // TXT
- p[2]=0;
- p[3]=1; // IN
-
- putLong(p+4,rr.ttl);
-
- p[8]=rr.content.length()/256;
- p[9]=rr.content.length()%256; // need to fill this in
-
- stringbuffer+=piece1;
- stringbuffer.append(p,10);
- stringbuffer+=rr.content;
- if(rr.d_place==DNSResourceRecord::ADDITIONAL)
- d.arcount++;
- else
- d.ancount++;
-}
/** Truncates a packet that has already been wrapup()-ed, possibly via a call to getData(). Do not call this function
before having done this - it will possibly break your packet, or crash your program.
stringbuffer[2]|=2; // set TC
}
-string DNSPacket::compress(const string &qd)
-{
- // input www.casema.net, output 3www6casema3net
- // input www.casema.net., output 3www6casema3net
- string qname = "";
-
- // Convert the name to a qname
-
- const char *p = qd.c_str();
- const char *q = strchr(p, '.');
-
- while (p <= (qd.c_str() + qd.length()))
- {
- int length = (q == NULL) ? strlen(p) : (q - p);
- if (length == 0) {
- break;
- }
- qname += (char) length;
- qname.append(p, length);
-
- if (q == NULL) {
- break;
- } else {
- p = q + 1;
- q = strchr(p, '.');
- }
- }
-
- qname += (char) 0x00;
- return qname;
-}
void DNSPacket::setQuestion(int op, const string &qd, int newqtype)
{
d.opcode=op;
qdomain=qd;
qtype=newqtype;
- string label=compress(qd);
- stringbuffer.assign((char *)&d,sizeof(d));
- stringbuffer.append(label);
- uint16_t tmp=htons(newqtype);
- stringbuffer.append((char *)&tmp,2);
- tmp=htons(1);
- stringbuffer.append((char *)&tmp,2);
-}
-
-/** A DNS answer packets needs to include the original question. This function allows you to
- paste in a question */
-void DNSPacket::pasteQ(const char *question, int length)
-{
- stringbuffer.replace(12, length, question, length); // bytes 12 & onward need to become *question
}
/** convenience function for creating a reply packet from a question packet. Do not forget to delete it after use! */
r->setID(d.id);
r->setOpcode(d.opcode);
- // reserve some space
- r->stringbuffer.reserve(d_qlen+12);
- // copy the question in
- r->pasteQ(stringbuffer.c_str()+12,d_qlen);
-
r->d_dt=d_dt;
r->d.qdcount=1;
r->d_tcp = d_tcp;
+ r->qdomain = qdomain;
+ r->qtype = qtype;
return r;
}
-int DNSPacket::findlabel(string &label)
+void DNSPacket::spoofQuestion(const string &qd)
{
- const char *data = stringbuffer.data();
- const char *p = data + 12;
-
- // Look in the question section
-
- for (unsigned int i = 0; i < d.qdcount; i++) {
- while (*p != 0x00) {
- // Skip compressed labels
- if ((*p & 0xC0) == 0xC0) {
- p += 1;
- break;
- }
- else {
- if (strncmp(p, label.data(), label.size()) == 0)
- return (p - data);
- p += (*p + 1);
- }
- }
-
- // Skip the tailing zero
- p++;
-
- // Skip the header
- p += 4;
- }
-
- // Look in the answer sections
-
- for (unsigned int i = 0; i < d.ancount + d.nscount + d.arcount; i++) {
- while (*p != 0x00) {
- // Skip compressed labels - means the end
- if ((*p & 0xC0) == 0xC0)
- {
- p += 1;
- break;
- }
- else
- {
- if (strncmp(p, label.data(), label.size()) == 0)
- {
- return (p - data);
- }
-
- p += (*p + 1);
- }
- }
-
- // Skip the trailing zero or other half of the ptr
-
- p++;
+ string label=simpleCompress(qd);
+ for(string::size_type i=0;i<label.size();++i)
+ stringbuffer[i+sizeof(d)]=label[i];
+ d_wrapped=true; // if we do this, don't later on wrapup
+}
- // Skip the header and data
-
- uint16_t dataLength = getShort(p+8);
- uint16_t type = getShort(p);
+/** This function takes data from the network, possibly received with recvfrom, and parses
+ it into our class. Results of calling this function multiple times on one packet are
+ unknown. Returns -1 if the packet cannot be parsed.
+*/
+int DNSPacket::parse(const char *mesg, int length)
+{
+ stringbuffer.assign(mesg,length);
- p += 10;
-
- // Check for NS, CNAME, PTR and MX records
-
- if (type == QType::NS || type == QType::CNAME || type == QType::PTR || type == QType::MX) {
- // For MX records, skip the preference field
- if (type == QType::MX){
- p += 2;
- }
+ len=length;
+ if(length < 12) {
+ L << Logger::Warning << "Ignoring packet: too short from "
+ << getRemote() << endl;
+ return -1;
+ }
+ MOADNSParser mdp(string(mesg, length));
- while (*p != 0x00) {
- //
- // Skip compressed labels
- //
-
- if ((*p & 0xC0) == 0xC0) {
- p += 1;
- break;
- }
- else {
+ memcpy((void *)&d,(const void *)stringbuffer.c_str(),12);
+ qdomain=mdp.d_qname;
+ if(!qdomain.empty()) // strip dot
+ erase_tail(qdomain, 1);
- if (strncmp(p, label.data(), label.size()) == 0) {
- return (p - data);
- }
-
- p += (*p + 1);
- }
- }
-
- // Skip the trailing zero or the last byte of a compresed label
- p++;
- }
- else {
- p += dataLength;
+ if(!ntohs(d.qdcount)) {
+ if(!d_tcp) {
+ L << Logger::Warning << "No question section in packet from " << getRemote() <<", rcode="<<(int)d.rcode<<endl;
+ return -1;
}
}
- return -1;
+ qtype=mdp.d_qtype;
+ qclass=mdp.d_qclass;
+ return 0;
}
-int DNSPacket::toqname(const char *name, string &qname, bool comp)
+//! Use this to set where this packet was received from or should be sent to
+void DNSPacket::setRemote(const ComboAddress *s)
{
- qname = compress(name);
-
- if (d_compress && comp) {
- // Now find a previous declared label. We work through the complete
- // name from left to right like this:
- // ns1.norad.org
- // norad.org
- // org
-
- int i = 0;
- bool containsptr=false;
-
- while (qname[i] != 0x00 && /* qname[i] == 0x00 => i == qname.length */
- (qname[i] & 0xC0) != 0xC0) { // no use to try to compress offsets
- // Get a portion of the name
-
- // qname must include an extra trailing '\0' if it's prefix
- // is not an offset ptr
- string s = qname.substr(i); /* s == qname[i..N) */
- if (!containsptr) s = s + '\0';
-
+ remote=*s;
+}
- // Did we see this before?
- int offset = findlabel(s);
-
- if ( offset != -1) {
- qname[i + 0] = (char) (((offset | 0xC000) & 0x0000FF00) >> 8);
- qname[i + 1] = (char) ((offset | 0xC000) & 0x000000FF);
- qname = qname.substr(0, i + 2); // XX setlength() ?
- containsptr=true;
- // qname now consists of unique prefix+known suffix (on location 'offset')
- // we managed to make qname shorter, maybe we can do that again
- i = 0;
-
- }
- else { /* offset == -1 */
- // Move to the next label
- i += (qname[i] + 1); // doesn't quite handle very long labels
- }
- }
- }
-
- return qname.length();
+void DNSPacket::spoofID(uint16_t id)
+{
+ stringbuffer[1]=(id>>8)&0xff;
+ stringbuffer[0]=id&0xff;
+ d.id=id;
}
-int DNSPacket::toqname(const string &name, string &qname, bool compress)
+void DNSPacket::setSocket(Utility::sock_t sock)
{
- return toqname(name.c_str(), qname, compress);
+ d_socket=sock;
}
-int DNSPacket::toqname(const string &name, string *qname, bool compress)
+void DNSPacket::commitD()
{
- return toqname(name.c_str(), *qname, compress);
+ stringbuffer.replace(0,12,(char *)&d,12); // copy in d
}
DNSPacket();
DNSPacket(const DNSPacket &orig);
- inline int parse(const char *mesg, int len); //!< parse a raw UDP or TCP packet and suck the data inward
+ int parse(const char *mesg, int len); //!< parse a raw UDP or TCP packet and suck the data inward
string getString(); //!< for serialization - just passes the whole packet
// address & socket manipulation
- inline void setRemote(const ComboAddress*);
+ void setRemote(const ComboAddress*);
string getRemote() const;
string getLocal() const
{
{
return d_socket;
}
- inline void setSocket(Utility::sock_t sock);
+ void setSocket(Utility::sock_t sock);
// these manipulate 'd'
DTime d_dt; //!< the time this packet was created. replyPacket() copies this in for you, so d_dt becomes the time spent processing the question+answer
void wrapup(void); // writes out queued rrs, and generates the binary packet. also shuffles. also rectifies dnsheader 'd', and copies it to the stringbuffer
- inline const char *getData(void); //!< get binary representation of packet, will call 'wrapup' for you
+ const char *getData(void); //!< get binary representation of packet, will call 'wrapup' for you
const char *getRaw(void); //!< provides access to the raw packet, possibly on a packet that has never been 'wrapped'
- inline void spoofID(uint16_t id); //!< change the ID of an existing packet. Useful for fixing up packets returned from the PacketCache
- inline void spoofQuestion(const string &qd); //!< paste in the exact right case of the question. Useful for PacketCache
+ void spoofID(uint16_t id); //!< change the ID of an existing packet. Useful for fixing up packets returned from the PacketCache
+ void spoofQuestion(const string &qd); //!< paste in the exact right case of the question. Useful for PacketCache
void truncate(int new_length); // has documentation in source
- bool needAP(); //!< query this to find out if this packet needs additional processing, based on rrs
vector<DNSResourceRecord*> getAPRecords(); //!< get a vector with DNSResourceRecords that need additional processing
void setCompress(bool compress);
DNSPacket *replyPacket() const; //!< convenience function that creates a virgin answer packet to this question
- inline void commitD(); //!< copies 'd' into the stringbuffer
+ void commitD(); //!< copies 'd' into the stringbuffer
//////// DATA !
private:
void pasteQ(const char *question, int length); //!< set the question of this packet, useful for crafting replies
- int expand(const unsigned char *begin, const unsigned char *end, string &expanded, int depth=0);
-
- string compress(const string &qd);
- void addARecord(const string&, uint32_t, uint32_t ttl, DNSResourceRecord::Place place); //!< add an A record to the packet
- void addARecord(const DNSResourceRecord &); //!< add an A record to the packet
-
- void addAAAARecord(const string &, unsigned char addr[16], uint32_t ttl, DNSResourceRecord::Place place); //!< add an A record to the packet
- void addAAAARecord(const DNSResourceRecord &); //!< add an A record to the packet
-
- void addMXRecord(const string &domain, const string &mx, int priority, uint32_t ttl); //!< add an MX record to the packet
- void addMXRecord(const DNSResourceRecord &); //!< add an MX record to the packet
-
- void addSRVRecord(const string &domain, const string &srv, int priority, uint32_t ttl); //!< add an SRVMX record to the packet
- void addSRVRecord(const DNSResourceRecord &); //!< add an SRV record to the packet
-
- void addMRRecord(const string &domain, const string &alias, uint32_t ttl); //!< add a MR record to the packet
- void addMRRecord(const DNSResourceRecord &); //!< add a MR record to the packet
-
- void addCNAMERecord(const string &domain, const string &alias, uint32_t ttl); //!< add a CNAME record to the packet
- void addCNAMERecord(const DNSResourceRecord &); //!< add a CNAME record to the packet
-
- void addRPRecord(const string &domain, const string &content, uint32_t ttl); //!< add a RP record to the packet
- void addRPRecord(const DNSResourceRecord &); //!< add a RP record to the packet
-
- void addNAPTRRecord(const string &domain, const string &content, uint32_t ttl); //!< add a NAPTR record to the packet
- void addNAPTRRecord(const DNSResourceRecord &); //!< add a NAPTR record to the packet
-
-
- void addPTRRecord(const string &domain, const string &alias, uint32_t ttl); //!< add a PTR record to the packet
- void addPTRRecord(const DNSResourceRecord &); //!< add a PTR record to the packet
-
- void addLOCRecord(const string &domain, const string &content, uint32_t ttl);
- void addLOCRecord(const DNSResourceRecord &); //!< add a LOC record to the packet
-
-
- /** Adds a SOA record to the packet. The SOA record is very special because we have a lot of default values,
- that may be overridden by the contents of the database. Content can have a variety of content:
-
- (nothing)
- hostmaster
- hostmaster serial-number
- hostmaster serial-number [refresh [retry [expire [ minimum] ] ] ]
-
- Suggested values are:
-
- 10800 ;refresh every three hours
- 300 ;retry every 5 min
- 604800 ;expire after a week
- 86400 ;default ttl
-
- An empty field means that we supply hostmaster+@+domain name as hostmaster. An empty serial number is replaced by the
- number of seconds since 1 jan 1970 (unix timestamp). The other values are substituted as indicated
-
- */
- void addSOARecord(const string &domain, const string &content, uint32_t ttl, DNSResourceRecord::Place place);
- void addSOARecord(const DNSResourceRecord &); //!< add a SOA record to the packet
-
- void addTXTorSPFRecord(uint16_t qtype, string domain, string, uint32_t ttl); //!< add a TXT or SPF record to the packet
-
- void addTXTRecord(const DNSResourceRecord &); //!< add a TXT record to the packet
- void addSPFRecord(const DNSResourceRecord &); //!< add a SPF record to the packet
-
- void addHINFORecord(string domain, string, uint32_t ttl); //!< add a HINFO record to the packet
- void addHINFORecord(const DNSResourceRecord &); //!< add a HINFO record to the packet
-
- void addNSRecord(string domain, string server, uint32_t ttl, DNSResourceRecord::Place place); //!< add an NS record to the packet
- void addNSRecord(const DNSResourceRecord &); //!< add an NS record to the packet
- void addGenericRecord(const DNSResourceRecord& rr);
-
bool d_wrapped; // 1
bool d_compress; // 1
uint16_t d_qlen; // length of the question (including class & type) in this packet 2
int d_socket; // 4
-
- int findlabel(string &label);
- int toqname(const char *name, string &qname, bool compress = true);
- int toqname(const string &name, string &qname, bool compress = true);
- int toqname(const string &name, string *qname, bool compress = true);
- const string makeSoaHostmasterPiece(const string &hostmaster);
- static string parseLOC(const unsigned char *p, unsigned int length);
- void makeHeader(char *p,uint16_t qtype, uint32_t ttl);
- int domprint();
- int getq();
-
- // MORE DATA!
string stringbuffer; // this is where everything lives 4
};
-inline void DNSPacket::spoofQuestion(const string &qd)
-{
- string label=compress(qd);
- for(string::size_type i=0;i<label.size();++i)
- stringbuffer[i+sizeof(d)]=label[i];
- d_wrapped=true; // if we do this, don't later on wrapup
-}
-
-/** This function takes data from the network, possibly received with recvfrom, and parses
- it into our class. Results of calling this function multiple times on one packet are
- unknown. Returns -1 if the packet cannot be parsed.
-*/
-int DNSPacket::parse(const char *mesg, int length)
-{
- stringbuffer.assign(mesg,length);
- len=length;
- if(length < 12) {
- L << Logger::Warning << "Ignoring packet: too short from "
- << getRemote() << endl;
- return -1;
- }
-
- memcpy((void *)&d,(const void *)stringbuffer.c_str(),12);
-
- int offset=0;
- d_qlen=0;
-
- if(!ntohs(d.qdcount)) {
- if(!d_tcp) {
- L << Logger::Warning << "No question section in packet from " << getRemote() <<", rcode="<<(int)d.rcode<<endl;
- return -1;
- }
- }
- else {
- offset = getq(); // also sets this->qdomain!
- d_qlen=offset+4; // this points to the start of any answers
- }
- if(offset < 0) {
- // L << Logger::Warning << "Ignoring packet: invalid label in question from "
- // << inet_ntoa(remote.sin_addr) << endl;
- return -1;
- }
- if(qdomain.length() > 255) { // this prevents crap from the rootservers
- return -1;
- }
-
-
-
- if((unsigned int)(15+offset)>=stringbuffer.length()) {
- L << Logger::Warning << "Ignoring packet: question too short from "<< getRemote()<<", offset "<<
- 15+offset<<">="<<stringbuffer.length()<<endl;
- return -1;
- }
-
- qtype=((unsigned char)stringbuffer[12+offset])*256+(unsigned char)stringbuffer[13+offset];
- qclass=((unsigned char)stringbuffer[14+offset]*256)+(unsigned char)stringbuffer[15+offset];
- return 0;
-}
-
-//! Use this to set where this packet was received from or should be sent to
-inline void DNSPacket::setRemote(const ComboAddress *s)
-{
- remote=*s;
-}
-
-inline void DNSPacket::spoofID(uint16_t id)
-{
- stringbuffer[1]=(id>>8)&0xff;
- stringbuffer[0]=id&0xff;
- d.id=id;
-}
-
-inline void DNSPacket::setSocket(Utility::sock_t sock)
-{
- d_socket=sock;
-}
-
-inline void DNSPacket::commitD()
-{
- stringbuffer.replace(0,12,(char *)&d,12); // copy in d
-}
-
-inline const char *DNSPacket::getData(void)
-{
- if(!d_wrapped)
- wrapup();
-
- return stringbuffer.data();
-}
-
#endif
projects / pdns / commitdiff