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#include "rpzloader.hh"
#include "zoneparser-tng.hh"
#include "dnsparser.hh"
#include "dnsrecords.hh"
#include "syncres.hh"
#include "resolver.hh"
#include "logger.hh"
#include "rec-lua-conf.hh"
static Netmask makeNetmaskFromRPZ(const DNSName& name)
{
auto parts = name.getRawLabels();
/*
* why 2?, the minimally valid IPv6 address that can be encoded in an RPZ is
* $NETMASK.zz (::/$NETMASK)
* Terrible right?
*/
if(parts.size() < 2 || parts.size() > 9)
throw PDNSException("Invalid IP address in RPZ: "+name.toString());
bool isV6 = (stoi(parts[0]) > 32);
bool hadZZ = false;
for (auto &part : parts) {
// Check if we have an IPv4 octet
for (auto c : part)
if (!isdigit(c))
isV6 = true;
if (pdns_iequals(part,"zz")) {
if (hadZZ)
throw PDNSException("more than one 'zz' label found in RPZ name"+name.toString());
part = "";
isV6 = true;
hadZZ = true;
}
}
if (isV6 && parts.size() < 9 && !hadZZ)
throw PDNSException("No 'zz' label found in an IPv6 RPZ name shorter than 9 elements: "+name.toString());
if (parts.size() == 5 && !isV6)
return Netmask(parts[4]+"."+parts[3]+"."+parts[2]+"."+parts[1]+"/"+parts[0]);
string v6;
for (uint8_t i = parts.size()-1 ; i > 0; i--) {
v6 += parts[i];
if (parts[i] == "" && i == 1 && i == parts.size()-1)
v6+= "::";
if (parts[i] == "" && i != parts.size()-1)
v6+= ":";
if (parts[i] != "" && i != 1)
v6 += ":";
}
v6 += "/" + parts[0];
return Netmask(v6);
}
void RPZRecordToPolicy(const DNSRecord& dr, DNSFilterEngine& target, bool addOrRemove, boost::optional<DNSFilterEngine::Policy> defpol, size_t place)
{
static const DNSName drop("rpz-drop."), truncate("rpz-tcp-only."), noaction("rpz-passthru.");
static const DNSName rpzClientIP("rpz-client-ip"), rpzIP("rpz-ip"),
rpzNSDname("rpz-nsdname"), rpzNSIP("rpz-nsip.");
DNSFilterEngine::Policy pol;
if(dr.d_class != QClass::IN) {
return;
}
if(dr.d_type == QType::CNAME) {
auto crc = getRR<CNAMERecordContent>(dr);
if (!crc) {
return;
}
auto target=crc->getTarget();
if(defpol) {
pol=*defpol;
}
else if(target.isRoot()) {
// cerr<<"Wants NXDOMAIN for "<<dr.d_name<<": ";
pol.d_kind = DNSFilterEngine::PolicyKind::NXDOMAIN;
} else if(target==DNSName("*")) {
// cerr<<"Wants NODATA for "<<dr.d_name<<": ";
pol.d_kind = DNSFilterEngine::PolicyKind::NODATA;
}
else if(target==drop) {
// cerr<<"Wants DROP for "<<dr.d_name<<": ";
pol.d_kind = DNSFilterEngine::PolicyKind::Drop;
}
else if(target==truncate) {
// cerr<<"Wants TRUNCATE for "<<dr.d_name<<": ";
pol.d_kind = DNSFilterEngine::PolicyKind::Truncate;
}
else if(target==noaction) {
// cerr<<"Wants NOACTION for "<<dr.d_name<<": ";
pol.d_kind = DNSFilterEngine::PolicyKind::NoAction;
}
else {
pol.d_kind = DNSFilterEngine::PolicyKind::Custom;
pol.d_custom = dr.d_content;
// cerr<<"Wants custom "<<target<<" for "<<dr.d_name<<": ";
}
}
else {
if (defpol) {
pol=*defpol;
}
else {
pol.d_kind = DNSFilterEngine::PolicyKind::Custom;
pol.d_custom = dr.d_content;
// cerr<<"Wants custom "<<dr.d_content->getZoneRepresentation()<<" for "<<dr.d_name<<": ";
}
}
if(pol.d_ttl < 0)
pol.d_ttl = dr.d_ttl;
// now to DO something with that
if(dr.d_name.isPartOf(rpzNSDname)) {
DNSName filt=dr.d_name.makeRelative(rpzNSDname);
if(addOrRemove)
target.addNSTrigger(filt, pol, place);
else
target.rmNSTrigger(filt, pol, place);
} else if(dr.d_name.isPartOf(rpzClientIP)) {
DNSName filt=dr.d_name.makeRelative(rpzClientIP);
auto nm=makeNetmaskFromRPZ(filt);
if(addOrRemove)
target.addClientTrigger(nm, pol, place);
else
target.rmClientTrigger(nm, pol, place);
} else if(dr.d_name.isPartOf(rpzIP)) {
// cerr<<"Should apply answer content IP policy: "<<dr.d_name<<endl;
DNSName filt=dr.d_name.makeRelative(rpzIP);
auto nm=makeNetmaskFromRPZ(filt);
if(addOrRemove)
target.addResponseTrigger(nm, pol, place);
else
target.rmResponseTrigger(nm, pol, place);
} else if(dr.d_name.isPartOf(rpzNSIP)) {
DNSName filt=dr.d_name.makeRelative(rpzNSIP);
auto nm=makeNetmaskFromRPZ(filt);
if(addOrRemove)
target.addNSIPTrigger(nm, pol, place);
else
target.rmNSIPTrigger(nm, pol, place);
} else {
if(addOrRemove)
target.addQNameTrigger(dr.d_name, pol, place);
else
target.rmQNameTrigger(dr.d_name, pol, place);
}
}
shared_ptr<SOARecordContent> loadRPZFromServer(const ComboAddress& master, const DNSName& zone, DNSFilterEngine& target, boost::optional<DNSFilterEngine::Policy> defpol, size_t place, const TSIGTriplet& tt, size_t maxReceivedBytes, const ComboAddress& localAddress)
{
L<<Logger::Warning<<"Loading RPZ zone '"<<zone<<"' from "<<master.toStringWithPort()<<endl;
if(!tt.name.empty())
L<<Logger::Warning<<"With TSIG key '"<<tt.name<<"' of algorithm '"<<tt.algo<<"'"<<endl;
ComboAddress local(localAddress);
if (local == ComboAddress())
local = getQueryLocalAddress(master.sin4.sin_family, 0);
AXFRRetriever axfr(master, zone, tt, &local, maxReceivedBytes);
unsigned int nrecords=0;
Resolver::res_t nop;
vector<DNSRecord> chunk;
time_t last=0;
shared_ptr<SOARecordContent> sr;
while(axfr.getChunk(nop, &chunk)) {
for(auto& dr : chunk) {
if(dr.d_type==QType::NS || dr.d_type==QType::TSIG) {
continue;
}
dr.d_name.makeUsRelative(zone);
if(dr.d_type==QType::SOA) {
sr = getRR<SOARecordContent>(dr);
continue;
}
RPZRecordToPolicy(dr, target, true, defpol, place);
nrecords++;
}
if(last != time(0)) {
L<<Logger::Info<<"Loaded & indexed "<<nrecords<<" policy records so far"<<endl;
last=time(0);
}
}
L<<Logger::Info<<"Done: "<<nrecords<<" policy records active, SOA: "<<sr->getZoneRepresentation()<<endl;
return sr;
}
// this function is silent - you do the logging
int loadRPZFromFile(const std::string& fname, DNSFilterEngine& target, boost::optional<DNSFilterEngine::Policy> defpol, size_t place)
{
ZoneParserTNG zpt(fname);
DNSResourceRecord drr;
DNSName domain;
while(zpt.get(drr)) {
try {
if(drr.qtype.getCode() == QType::CNAME && drr.content.empty())
drr.content=".";
DNSRecord dr(drr);
if(dr.d_type == QType::SOA) {
domain = dr.d_name;
}
else if(dr.d_type == QType::NS) {
continue;
}
else {
dr.d_name=dr.d_name.makeRelative(domain);
RPZRecordToPolicy(dr, target, true, defpol, place);
}
}
catch(PDNSException& pe) {
throw PDNSException("Issue parsing '"+drr.qname.toString()+"' '"+drr.content+"' at "+zpt.getLineOfFile()+": "+pe.reason);
}
}
return place;
}
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