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#define BOOST_TEST_DYN_LINK
#define BOOST_TEST_NO_MAIN
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <boost/test/unit_test.hpp>
#include "dnsparser.hh"
BOOST_AUTO_TEST_SUITE(test_dnsparser_cc)
BOOST_AUTO_TEST_CASE(test_editDNSPacketTTL) {
auto generatePacket = [](uint32_t ttl) {
DNSName name("powerdns.com.");
ComboAddress v4("1.2.3.4");
ComboAddress v6("2001:db8::1");
vector<uint8_t> packet;
DNSPacketWriter pwR(packet, name, QType::A, QClass::IN, 0);
pwR.getHeader()->qr = 1;
/* record we want to see altered */
pwR.startRecord(name, QType::A, ttl, QClass::IN, DNSResourceRecord::ANSWER);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
/* same record but different TTL (yeah, don't do that but it's just a test) */
pwR.startRecord(name, QType::A, 100, QClass::IN, DNSResourceRecord::ANSWER);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
/* different type */
pwR.startRecord(name, QType::AAAA, 42, QClass::IN, DNSResourceRecord::ANSWER);
pwR.xfrIP6(std::string(reinterpret_cast<const char*>(v6.sin6.sin6_addr.s6_addr), 16));
pwR.commit();
/* different class */
pwR.startRecord(name, QType::A, 42, QClass::CHAOS, DNSResourceRecord::ANSWER);
pwR.commit();
/* different section */
pwR.startRecord(name, QType::A, 42, QClass::IN, DNSResourceRecord::AUTHORITY);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
return packet;
};
auto firstPacket = generatePacket(42);
auto expectedAlteredPacket = generatePacket(84);
size_t called = 0;
editDNSPacketTTL(reinterpret_cast<char*>(firstPacket.data()), firstPacket.size(), [&called](uint8_t section, uint16_t class_, uint16_t type, uint32_t ttl) {
called++;
/* only updates the TTL of IN/A, in answer, with an existing ttl of 42 */
if (section == 1 && class_ == QClass::IN && type == QType::A && ttl == 42) {
return 84;
}
return 0;
});
/* check that we have been for all records */
BOOST_CHECK_EQUAL(called, 5U);
BOOST_REQUIRE_EQUAL(firstPacket.size(), expectedAlteredPacket.size());
for (size_t idx = 0; idx < firstPacket.size(); idx++) {
BOOST_CHECK_EQUAL(firstPacket.at(idx), expectedAlteredPacket.at(idx));
}
BOOST_CHECK(firstPacket == expectedAlteredPacket);
/* now call it with a truncated packet, missing the last TTL and rdata,
we should only be called 4 times but everything else should be fine. */
called = 0;
editDNSPacketTTL(reinterpret_cast<char*>(firstPacket.data()), firstPacket.size() - sizeof(uint32_t) - /* rdata length */ sizeof (uint16_t) - /* IPv4 payload in rdata */ 4, [&called](uint8_t section, uint16_t class_, uint16_t type, uint32_t ttl) {
called++;
/* only updates the TTL of IN/A, in answer, with an existing ttl of 42 */
if (section == 1 && class_ == QClass::IN && type == QType::A && ttl == 42) {
return 84;
}
return 0;
});
/* check that we have been for all records */
BOOST_CHECK_EQUAL(called, 4U);
BOOST_CHECK(firstPacket == expectedAlteredPacket);
}
BOOST_AUTO_TEST_CASE(test_ageDNSPacket) {
auto generatePacket = [](uint32_t ttl) {
DNSName name("powerdns.com.");
ComboAddress v4("1.2.3.4");
ComboAddress v6("2001:db8::1");
vector<uint8_t> packet;
DNSPacketWriter pwR(packet, name, QType::A, QClass::IN, 0);
pwR.getHeader()->qr = 1;
/* record we want to see altered */
pwR.startRecord(name, QType::A, ttl, QClass::IN, DNSResourceRecord::ANSWER);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
pwR.addOpt(4096, 0, 0);
pwR.commit();
return packet;
};
auto firstPacket = generatePacket(3600);
auto expectedAlteredPacket = generatePacket(1800);
ageDNSPacket(reinterpret_cast<char*>(firstPacket.data()), firstPacket.size(), 1800);
BOOST_REQUIRE_EQUAL(firstPacket.size(), expectedAlteredPacket.size());
for (size_t idx = 0; idx < firstPacket.size(); idx++) {
BOOST_CHECK_EQUAL(firstPacket.at(idx), expectedAlteredPacket.at(idx));
}
BOOST_CHECK(firstPacket == expectedAlteredPacket);
/* now call it with a truncated packet, missing the last TTL and rdata,
the packet should not be altered. */
ageDNSPacket(reinterpret_cast<char*>(firstPacket.data()), firstPacket.size() - sizeof(uint32_t) - /* rdata length */ sizeof (uint16_t) - /* IPv4 payload in rdata */ 4 - /* size of OPT record */ 11, 900);
BOOST_CHECK(firstPacket == expectedAlteredPacket);
/* now remove more than the remaining TTL. We expect ageDNSPacket
to cap this at zero and not cause an unsigned underflow into
the 2^32-1 neighbourhood */
ageDNSPacket(reinterpret_cast<char*>(firstPacket.data()), firstPacket.size(), 1801);
uint32_t ttl = 0;
expectedAlteredPacket = generatePacket(ttl);
BOOST_REQUIRE_EQUAL(firstPacket.size(), expectedAlteredPacket.size());
for (size_t idx = 0; idx < firstPacket.size(); idx++) {
BOOST_CHECK_EQUAL(firstPacket.at(idx), expectedAlteredPacket.at(idx));
}
BOOST_CHECK(firstPacket == expectedAlteredPacket);
}
BOOST_AUTO_TEST_CASE(test_getDNSPacketMinTTL) {
const DNSName name("powerdns.com.");
const ComboAddress v4("1.2.3.4");
const ComboAddress v6("2001:db8::1");
{
/* no records */
vector<uint8_t> packet;
DNSPacketWriter pwR(packet, name, QType::A, QClass::IN, 0);
pwR.getHeader()->qr = 1;
pwR.commit();
auto result = getDNSPacketMinTTL(reinterpret_cast<char*>(packet.data()), packet.size(), nullptr);
BOOST_CHECK_EQUAL(result, std::numeric_limits<uint32_t>::max());
}
{
/* only one record, not an OPT one */
uint32_t ttl = 42;
vector<uint8_t> packet;
DNSPacketWriter pwR(packet, name, QType::A, QClass::IN, 0);
pwR.getHeader()->qr = 1;
pwR.commit();
pwR.startRecord(name, QType::A, ttl, QClass::IN, DNSResourceRecord::ANSWER);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
auto result = getDNSPacketMinTTL(reinterpret_cast<char*>(packet.data()), packet.size(), nullptr);
BOOST_CHECK_EQUAL(result, ttl);
}
{
/* only one record, an OPT one */
vector<uint8_t> packet;
DNSPacketWriter pwR(packet, name, QType::A, QClass::IN, 0);
pwR.getHeader()->qr = 1;
pwR.commit();
pwR.addOpt(4096, 0, 0);
pwR.commit();
auto result = getDNSPacketMinTTL(reinterpret_cast<char*>(packet.data()), packet.size(), nullptr);
BOOST_CHECK_EQUAL(result, std::numeric_limits<uint32_t>::max());
}
{
/* records with different TTLs, should return the lower */
vector<uint8_t> packet;
DNSPacketWriter pwR(packet, name, QType::A, QClass::IN, 0);
pwR.getHeader()->qr = 1;
pwR.commit();
pwR.startRecord(name, QType::A, 257, QClass::IN, DNSResourceRecord::ANSWER);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
pwR.startRecord(name, QType::A, 255, QClass::IN, DNSResourceRecord::AUTHORITY);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
pwR.startRecord(name, QType::A, 256, QClass::IN, DNSResourceRecord::ADDITIONAL);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
auto result = getDNSPacketMinTTL(reinterpret_cast<char*>(packet.data()), packet.size(), nullptr);
BOOST_CHECK_EQUAL(result, 255U);
}
{
/* SOA record in answer, seenAuthSOA should not be set */
vector<uint8_t> packet;
DNSPacketWriter pwR(packet, name, QType::A, QClass::IN, 0);
pwR.getHeader()->qr = 1;
pwR.commit();
pwR.startRecord(name, QType::SOA, 257, QClass::IN, DNSResourceRecord::ANSWER);
pwR.commit();
pwR.startRecord(name, QType::A, 255, QClass::IN, DNSResourceRecord::AUTHORITY);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
pwR.startRecord(name, QType::A, 256, QClass::IN, DNSResourceRecord::ADDITIONAL);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
bool seenAuthSOA = false;
auto result = getDNSPacketMinTTL(reinterpret_cast<char*>(packet.data()), packet.size(), &seenAuthSOA);
BOOST_CHECK_EQUAL(result, 255U);
BOOST_CHECK_EQUAL(seenAuthSOA, false);
}
{
/* one SOA record in auth, seenAuthSOA should be set */
vector<uint8_t> packet;
DNSPacketWriter pwR(packet, name, QType::A, QClass::IN, 0);
pwR.getHeader()->qr = 1;
pwR.commit();
pwR.startRecord(name, QType::A, 255, QClass::IN, DNSResourceRecord::ANSWER);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
pwR.startRecord(name, QType::SOA, 257, QClass::IN, DNSResourceRecord::AUTHORITY);
pwR.commit();
pwR.startRecord(name, QType::A, 256, QClass::IN, DNSResourceRecord::ADDITIONAL);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
bool seenAuthSOA = false;
auto result = getDNSPacketMinTTL(reinterpret_cast<char*>(packet.data()), packet.size(), &seenAuthSOA);
BOOST_CHECK_EQUAL(result, 255U);
BOOST_CHECK_EQUAL(seenAuthSOA, true);
}
{
/* one SOA record of the wrong qclass in auth, seenAuthSOA should not be set */
vector<uint8_t> packet;
DNSPacketWriter pwR(packet, name, QType::A, QClass::IN, 0);
pwR.getHeader()->qr = 1;
pwR.commit();
pwR.startRecord(name, QType::A, 257, QClass::IN, DNSResourceRecord::ANSWER);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
pwR.startRecord(name, QType::SOA, 255, QClass::CHAOS, DNSResourceRecord::AUTHORITY);
pwR.commit();
pwR.startRecord(name, QType::A, 256, QClass::IN, DNSResourceRecord::ADDITIONAL);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
bool seenAuthSOA = false;
auto result = getDNSPacketMinTTL(reinterpret_cast<char*>(packet.data()), packet.size(), &seenAuthSOA);
BOOST_CHECK_EQUAL(result, 255U);
BOOST_CHECK_EQUAL(seenAuthSOA, false);
}
{
/* one A record in auth, seenAuthSOA should not be set */
vector<uint8_t> packet;
DNSPacketWriter pwR(packet, name, QType::A, QClass::IN, 0);
pwR.getHeader()->qr = 1;
pwR.commit();
pwR.startRecord(name, QType::A, 257, QClass::IN, DNSResourceRecord::AUTHORITY);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
bool seenAuthSOA = false;
auto result = getDNSPacketMinTTL(reinterpret_cast<char*>(packet.data()), packet.size(), &seenAuthSOA);
BOOST_CHECK_EQUAL(result, 257U);
BOOST_CHECK_EQUAL(seenAuthSOA, false);
}
{
/* one SOA record in additional, seenAuthSOA should not be set */
vector<uint8_t> packet;
DNSPacketWriter pwR(packet, name, QType::A, QClass::IN, 0);
pwR.getHeader()->qr = 1;
pwR.commit();
pwR.startRecord(name, QType::SOA, 255, QClass::IN, DNSResourceRecord::ADDITIONAL);
pwR.commit();
bool seenAuthSOA = false;
auto result = getDNSPacketMinTTL(reinterpret_cast<char*>(packet.data()), packet.size(), &seenAuthSOA);
BOOST_CHECK_EQUAL(result, 255U);
BOOST_CHECK_EQUAL(seenAuthSOA, false);
}
{
/* truncated packet, no exception should be raised */
/* one SOA record in auth, seenAuthSOA should be set */
vector<uint8_t> packet;
DNSPacketWriter pwR(packet, name, QType::A, QClass::IN, 0);
pwR.getHeader()->qr = 1;
pwR.commit();
pwR.startRecord(name, QType::A, 255, QClass::IN, DNSResourceRecord::ANSWER);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
pwR.startRecord(name, QType::SOA, 257, QClass::IN, DNSResourceRecord::AUTHORITY);
pwR.commit();
pwR.startRecord(name, QType::A, 254, QClass::IN, DNSResourceRecord::ADDITIONAL);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
bool seenAuthSOA = false;
auto result = getDNSPacketMinTTL(reinterpret_cast<char*>(packet.data()), packet.size() - sizeof(uint32_t) - /* rdata length */ sizeof (uint16_t) - /* IPv4 payload in rdata */ 4, &seenAuthSOA);
BOOST_CHECK_EQUAL(result, 255U);
BOOST_CHECK_EQUAL(seenAuthSOA, true);
}
}
BOOST_AUTO_TEST_CASE(test_getDNSPacketLength) {
const DNSName name("powerdns.com.");
const ComboAddress v4("1.2.3.4");
const ComboAddress v6("2001:db8::1");
{
/* no records */
vector<uint8_t> packet;
DNSPacketWriter pwR(packet, name, QType::A, QClass::IN, 0);
pwR.getHeader()->qr = 1;
pwR.commit();
auto result = getDNSPacketLength(reinterpret_cast<char*>(packet.data()), packet.size());
BOOST_CHECK_EQUAL(result, packet.size());
}
{
/* several records */
vector<uint8_t> packet;
DNSPacketWriter pwR(packet, name, QType::A, QClass::IN, 0);
pwR.getHeader()->qr = 1;
pwR.commit();
pwR.startRecord(name, QType::A, 255, QClass::IN, DNSResourceRecord::ANSWER);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
pwR.startRecord(name, QType::SOA, 257, QClass::IN, DNSResourceRecord::AUTHORITY);
pwR.commit();
pwR.startRecord(name, QType::A, 256, QClass::IN, DNSResourceRecord::ADDITIONAL);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
pwR.addOpt(4096, 0, 0);
pwR.commit();
auto result = getDNSPacketLength(reinterpret_cast<char*>(packet.data()), packet.size());
BOOST_CHECK_EQUAL(result, packet.size());
}
{
/* trailing data */
vector<uint8_t> packet;
DNSPacketWriter pwR(packet, name, QType::A, QClass::IN, 0);
pwR.getHeader()->qr = 1;
pwR.commit();
pwR.startRecord(name, QType::A, 255, QClass::IN, DNSResourceRecord::ANSWER);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
pwR.startRecord(name, QType::SOA, 257, QClass::IN, DNSResourceRecord::AUTHORITY);
pwR.commit();
pwR.startRecord(name, QType::A, 256, QClass::IN, DNSResourceRecord::ADDITIONAL);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
pwR.addOpt(4096, 0, 0);
pwR.commit();
auto realSize = packet.size();
packet.resize(realSize + 512);
auto result = getDNSPacketLength(reinterpret_cast<char*>(packet.data()), packet.size());
BOOST_CHECK_EQUAL(result, realSize);
}
{
/* truncated packet, should return the full size */
vector<uint8_t> packet;
DNSPacketWriter pwR(packet, name, QType::A, QClass::IN, 0);
pwR.getHeader()->qr = 1;
pwR.commit();
pwR.startRecord(name, QType::A, 255, QClass::IN, DNSResourceRecord::ANSWER);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
pwR.startRecord(name, QType::SOA, 257, QClass::IN, DNSResourceRecord::AUTHORITY);
pwR.commit();
pwR.startRecord(name, QType::A, 256, QClass::IN, DNSResourceRecord::ADDITIONAL);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
pwR.addOpt(4096, 0, 0);
pwR.commit();
size_t fakeSize = packet.size()-1;
auto result = getDNSPacketLength(reinterpret_cast<char*>(packet.data()), fakeSize);
BOOST_CHECK_EQUAL(result, fakeSize);
}
}
BOOST_AUTO_TEST_CASE(test_getRecordsOfTypeCount) {
const DNSName name("powerdns.com.");
const ComboAddress v4("1.2.3.4");
const ComboAddress v6("2001:db8::1");
{
vector<uint8_t> packet;
DNSPacketWriter pwR(packet, name, QType::A, QClass::IN, 0);
pwR.getHeader()->qr = 1;
pwR.commit();
pwR.startRecord(name, QType::A, 255, QClass::IN, DNSResourceRecord::ANSWER);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
pwR.startRecord(name, QType::SOA, 257, QClass::IN, DNSResourceRecord::AUTHORITY);
pwR.commit();
pwR.startRecord(name, QType::A, 256, QClass::IN, DNSResourceRecord::ADDITIONAL);
pwR.xfrIP(v4.sin4.sin_addr.s_addr);
pwR.commit();
pwR.addOpt(4096, 0, 0);
pwR.commit();
BOOST_CHECK_EQUAL(getRecordsOfTypeCount(reinterpret_cast<char*>(packet.data()), packet.size(), 0, QType::A), 1);
BOOST_CHECK_EQUAL(getRecordsOfTypeCount(reinterpret_cast<char*>(packet.data()), packet.size(), 0, QType::SOA), 0);
BOOST_CHECK_EQUAL(getRecordsOfTypeCount(reinterpret_cast<char*>(packet.data()), packet.size(), 1, QType::A), 1);
BOOST_CHECK_EQUAL(getRecordsOfTypeCount(reinterpret_cast<char*>(packet.data()), packet.size(), 1, QType::SOA), 0);
BOOST_CHECK_EQUAL(getRecordsOfTypeCount(reinterpret_cast<char*>(packet.data()), packet.size(), 2, QType::A), 0);
BOOST_CHECK_EQUAL(getRecordsOfTypeCount(reinterpret_cast<char*>(packet.data()), packet.size(), 2, QType::SOA), 1);
BOOST_CHECK_EQUAL(getRecordsOfTypeCount(reinterpret_cast<char*>(packet.data()), packet.size(), 3, QType::A), 1);
BOOST_CHECK_EQUAL(getRecordsOfTypeCount(reinterpret_cast<char*>(packet.data()), packet.size(), 3, QType::SOA), 0);
BOOST_CHECK_EQUAL(getRecordsOfTypeCount(reinterpret_cast<char*>(packet.data()), packet.size(), 4, QType::SOA), 0);
}
}
BOOST_AUTO_TEST_SUITE_END()
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