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#include "ares-test.h"
#include "dns-proto.h"
#include <sstream>
#include <vector>
namespace ares {
namespace test {
TEST_F(LibraryTest, ParseAReplyOK) {
DNSPacket pkt;
pkt.set_qid(0x1234).set_response().set_aa()
.add_question(new DNSQuestion("example.com", ns_t_a))
.add_answer(new DNSARR("example.com", 0x01020304, {2,3,4,5}));
std::vector<byte> data = {
0x12, 0x34, // qid
0x84, // response + query + AA + not-TC + not-RD
0x00, // not-RA + not-Z + not-AD + not-CD + rc=NoError
0x00, 0x01, // num questions
0x00, 0x01, // num answer RRs
0x00, 0x00, // num authority RRs
0x00, 0x00, // num additional RRs
// Question
0x07, 'e', 'x', 'a', 'm', 'p', 'l', 'e',
0x03, 'c', 'o', 'm',
0x00,
0x00, 0x01, // type A
0x00, 0x01, // class IN
// Answer 1
0x07, 'e', 'x', 'a', 'm', 'p', 'l', 'e',
0x03, 'c', 'o', 'm',
0x00,
0x00, 0x01, // RR type
0x00, 0x01, // class IN
0x01, 0x02, 0x03, 0x04, // TTL
0x00, 0x04, // rdata length
0x02, 0x03, 0x04, 0x05,
};
EXPECT_EQ(data, pkt.data());
struct hostent *host = nullptr;
struct ares_addrttl info[5];
int count = 5;
EXPECT_EQ(ARES_SUCCESS, ares_parse_a_reply(data.data(), data.size(),
&host, info, &count));
EXPECT_EQ(1, count);
EXPECT_EQ(0x01020304, info[0].ttl);
unsigned long expected_addr = htonl(0x02030405);
EXPECT_EQ(expected_addr, info[0].ipaddr.s_addr);
EXPECT_EQ("2.3.4.5", AddressToString(&(info[0].ipaddr), 4));
ASSERT_NE(nullptr, host);
std::stringstream ss;
ss << HostEnt(host);
EXPECT_EQ("{'example.com' aliases=[] addrs=[2.3.4.5]}", ss.str());
ares_free_hostent(host);
// Repeat without providing a hostent
EXPECT_EQ(ARES_SUCCESS, ares_parse_a_reply(data.data(), data.size(),
nullptr, info, &count));
EXPECT_EQ(1, count);
EXPECT_EQ(0x01020304, info[0].ttl);
EXPECT_EQ(expected_addr, info[0].ipaddr.s_addr);
EXPECT_EQ("2.3.4.5", AddressToString(&(info[0].ipaddr), 4));
}
TEST_F(LibraryTest, ParseMalformedAReply) {
std::vector<byte> data = {
0x12, 0x34, // [0:2) qid
0x84, // [2] response + query + AA + not-TC + not-RD
0x00, // [3] not-RA + not-Z + not-AD + not-CD + rc=NoError
0x00, 0x01, // [4:6) num questions
0x00, 0x01, // [6:8) num answer RRs
0x00, 0x00, // [8:10) num authority RRs
0x00, 0x00, // [10:12) num additional RRs
// Question
0x07, 'e', 'x', 'a', 'm', 'p', 'l', 'e', // [12:20)
0x03, 'c', 'o', 'm', // [20,24)
0x00, // [24]
0x00, 0x01, // [25:26) type A
0x00, 0x01, // [27:29) class IN
// Answer 1
0x07, 'e', 'x', 'a', 'm', 'p', 'l', 'e', // [29:37)
0x03, 'c', 'o', 'm', // [37:41)
0x00, // [41]
0x00, 0x01, // [42:44) RR type
0x00, 0x01, // [44:46) class IN
0x01, 0x02, 0x03, 0x04, // [46:50) TTL
0x00, 0x04, // [50:52) rdata length
0x02, 0x03, 0x04, 0x05, // [52,56)
};
struct hostent *host = nullptr;
struct ares_addrttl info[2];
int count = 2;
// Invalid RR-len.
std::vector<byte> invalid_rrlen(data);
invalid_rrlen[51] = 180;
EXPECT_EQ(ARES_EBADRESP, ares_parse_a_reply(invalid_rrlen.data(), invalid_rrlen.size(),
&host, info, &count));
// Truncate mid-question.
EXPECT_EQ(ARES_EBADRESP, ares_parse_a_reply(data.data(), 26,
&host, info, &count));
// Truncate mid-answer.
EXPECT_EQ(ARES_EBADRESP, ares_parse_a_reply(data.data(), 42,
&host, info, &count));
}
TEST_F(LibraryTest, ParseAReplyNoData) {
DNSPacket pkt;
pkt.set_qid(0x1234).set_response().set_aa()
.add_question(new DNSQuestion("example.com", ns_t_a));
std::vector<byte> data = pkt.data();
struct hostent *host = nullptr;
struct ares_addrttl info[2];
int count = 2;
EXPECT_EQ(ARES_ENODATA, ares_parse_a_reply(data.data(), data.size(),
&host, info, &count));
EXPECT_EQ(0, count);
EXPECT_EQ(nullptr, host);
// Again but with a CNAME.
pkt.add_answer(new DNSCnameRR("example.com", 200, "c.example.com"));
EXPECT_EQ(ARES_ENODATA, ares_parse_a_reply(data.data(), data.size(),
&host, info, &count));
EXPECT_EQ(0, count);
EXPECT_EQ(nullptr, host);
}
TEST_F(LibraryTest, ParseAReplyVariantA) {
DNSPacket pkt;
pkt.set_qid(6366).set_rd().set_ra()
.add_question(new DNSQuestion("mit.edu", ns_t_a))
.add_answer(new DNSARR("mit.edu", 52, {18,7,22,69}))
.add_auth(new DNSNsRR("mit.edu", 292, "W20NS.mit.edu"))
.add_auth(new DNSNsRR("mit.edu", 292, "BITSY.mit.edu"))
.add_auth(new DNSNsRR("mit.edu", 292, "STRAWB.mit.edu"))
.add_additional(new DNSARR("STRAWB.mit.edu", 292, {18,71,0,151}));
struct hostent *host = nullptr;
struct ares_addrttl info[2];
int count = 2;
std::vector<byte> data = pkt.data();
EXPECT_EQ(ARES_SUCCESS, ares_parse_a_reply(data.data(), data.size(),
&host, info, &count));
EXPECT_EQ(1, count);
EXPECT_EQ("18.7.22.69", AddressToString(&(info[0].ipaddr), 4));
EXPECT_EQ(52, info[0].ttl);
ares_free_hostent(host);
}
TEST_F(LibraryTest, ParseAReplyJustCname) {
DNSPacket pkt;
pkt.set_qid(6366).set_rd().set_ra()
.add_question(new DNSQuestion("mit.edu", ns_t_a))
.add_answer(new DNSCnameRR("mit.edu", 52, "other.mit.edu"));
struct hostent *host = nullptr;
struct ares_addrttl info[2];
int count = 2;
std::vector<byte> data = pkt.data();
EXPECT_EQ(ARES_SUCCESS, ares_parse_a_reply(data.data(), data.size(),
&host, info, &count));
EXPECT_EQ(0, count);
ASSERT_NE(nullptr, host);
std::stringstream ss;
ss << HostEnt(host);
EXPECT_EQ("{'other.mit.edu' aliases=[mit.edu] addrs=[]}", ss.str());
ares_free_hostent(host);
}
TEST_F(LibraryTest, ParseAReplyVariantCname) {
DNSPacket pkt;
pkt.set_qid(6366).set_rd().set_ra()
.add_question(new DNSQuestion("query.example.com", ns_t_a))
.add_answer(new DNSCnameRR("query.example.com", 200, "redirect.query.example.com"))
.add_answer(new DNSARR("redirect.query.example.com", 300, {129,97,123,22}))
.add_auth(new DNSNsRR("example.com", 218, "aa.ns1.example.com"))
.add_auth(new DNSNsRR("example.com", 218, "ns2.example.com"))
.add_auth(new DNSNsRR("example.com", 218, "ns3.example.com"))
.add_auth(new DNSNsRR("example.com", 218, "ns4.example.com"))
.add_additional(new DNSARR("aa.ns1.example.com", 218, {129,97,1,1}))
.add_additional(new DNSARR("ns2.example.com", 218, {129,97,1,2}))
.add_additional(new DNSARR("ns3.example.com", 218, {129,97,1,3}))
.add_additional(new DNSARR("ns4.example.com", 218, {129,97,1,4}));
struct hostent *host = nullptr;
struct ares_addrttl info[2];
int count = 2;
std::vector<byte> data = pkt.data();
EXPECT_EQ(ARES_SUCCESS, ares_parse_a_reply(data.data(), data.size(),
&host, info, &count));
EXPECT_EQ(1, count);
EXPECT_EQ("129.97.123.22", AddressToString(&(info[0].ipaddr), 4));
// TTL is reduced to match CNAME's.
EXPECT_EQ(200, info[0].ttl);
ares_free_hostent(host);
// Repeat parsing without places to put the results.
count = 0;
EXPECT_EQ(ARES_SUCCESS, ares_parse_a_reply(data.data(), data.size(),
nullptr, info, &count));
}
TEST_F(LibraryTest, ParseAReplyVariantCnameChain) {
DNSPacket pkt;
pkt.set_qid(6366).set_rd().set_ra()
.add_question(new DNSQuestion("c1.localhost", ns_t_a))
.add_answer(new DNSCnameRR("c1.localhost", 604800, "c2.localhost"))
.add_answer(new DNSCnameRR("c2.localhost", 604800, "c3.localhost"))
.add_answer(new DNSCnameRR("c3.localhost", 604800, "c4.localhost"))
.add_answer(new DNSARR("c4.localhost", 604800, {8,8,8,8}))
.add_auth(new DNSNsRR("localhost", 604800, "localhost"))
.add_additional(new DNSARR("localhost", 604800, {127,0,0,1}))
.add_additional(new DNSAaaaRR("localhost", 604800,
{0x7F, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01}));
struct hostent *host = nullptr;
struct ares_addrttl info[2];
int count = 2;
std::vector<byte> data = pkt.data();
EXPECT_EQ(ARES_SUCCESS, ares_parse_a_reply(data.data(), data.size(),
&host, info, &count));
EXPECT_EQ(1, count);
EXPECT_EQ("8.8.8.8", AddressToString(&(info[0].ipaddr), 4));
EXPECT_EQ(604800, info[0].ttl);
ares_free_hostent(host);
}
TEST_F(LibraryTest, DISABLED_ParseAReplyVariantCnameLast) {
DNSPacket pkt;
pkt.set_qid(6366).set_rd().set_ra()
.add_question(new DNSQuestion("query.example.com", ns_t_a))
.add_answer(new DNSARR("redirect.query.example.com", 300, {129,97,123,221}))
.add_answer(new DNSARR("redirect.query.example.com", 300, {129,97,123,222}))
.add_answer(new DNSARR("redirect.query.example.com", 300, {129,97,123,223}))
.add_answer(new DNSARR("redirect.query.example.com", 300, {129,97,123,224}))
.add_answer(new DNSCnameRR("query.example.com", 60, "redirect.query.example.com"))
.add_additional(new DNSTxtRR("query.example.com", 60, {"text record"}));
struct hostent *host = nullptr;
struct ares_addrttl info[8];
int count = 8;
std::vector<byte> data = pkt.data();
EXPECT_EQ(ARES_SUCCESS, ares_parse_a_reply(data.data(), data.size(),
&host, info, &count));
EXPECT_EQ(4, count);
EXPECT_EQ("129.97.123.221", AddressToString(&(info[0].ipaddr), 4));
EXPECT_EQ("129.97.123.222", AddressToString(&(info[1].ipaddr), 4));
EXPECT_EQ("129.97.123.223", AddressToString(&(info[2].ipaddr), 4));
EXPECT_EQ("129.97.123.224", AddressToString(&(info[3].ipaddr), 4));
EXPECT_EQ(300, info[0].ttl);
EXPECT_EQ(300, info[1].ttl);
EXPECT_EQ(300, info[2].ttl);
EXPECT_EQ(300, info[3].ttl);
ares_free_hostent(host);
}
TEST_F(LibraryTest, ParseAReplyErrors) {
DNSPacket pkt;
pkt.set_qid(0x1234).set_response().set_aa()
.add_question(new DNSQuestion("example.com", ns_t_a))
.add_answer(new DNSARR("example.com", 100, {0x02, 0x03, 0x04, 0x05}));
std::vector<byte> data;
struct hostent *host = nullptr;
struct ares_addrttl info[2];
int count = 2;
// No question.
pkt.questions_.clear();
data = pkt.data();
EXPECT_EQ(ARES_EBADRESP, ares_parse_a_reply(data.data(), data.size(),
&host, info, &count));
EXPECT_EQ(nullptr, host);
pkt.add_question(new DNSQuestion("example.com", ns_t_a));
// Question != answer
pkt.questions_.clear();
pkt.add_question(new DNSQuestion("Axample.com", ns_t_a));
data = pkt.data();
EXPECT_EQ(ARES_ENODATA, ares_parse_a_reply(data.data(), data.size(),
&host, info, &count));
EXPECT_EQ(nullptr, host);
pkt.questions_.clear();
pkt.add_question(new DNSQuestion("example.com", ns_t_a));
#ifdef DISABLED
// Not a response.
pkt.set_response(false);
data = pkt.data();
EXPECT_EQ(ARES_EBADRESP, ares_parse_a_reply(data.data(), data.size(),
&host, info, &count));
EXPECT_EQ(nullptr, host);
pkt.set_response(true);
// Bad return code.
pkt.set_rcode(ns_r_formerr);
data = pkt.data();
EXPECT_EQ(ARES_ENODATA, ares_parse_a_reply(data.data(), data.size(),
&host, info, &count));
EXPECT_EQ(nullptr, host);
pkt.set_rcode(ns_r_noerror);
#endif
// Two questions
pkt.add_question(new DNSQuestion("example.com", ns_t_a));
data = pkt.data();
EXPECT_EQ(ARES_EBADRESP, ares_parse_a_reply(data.data(), data.size(),
&host, info, &count));
EXPECT_EQ(nullptr, host);
pkt.questions_.clear();
pkt.add_question(new DNSQuestion("example.com", ns_t_a));
// Wrong sort of answer.
pkt.answers_.clear();
pkt.add_answer(new DNSMxRR("example.com", 100, 100, "mx1.example.com"));
data = pkt.data();
EXPECT_EQ(ARES_ENODATA, ares_parse_a_reply(data.data(), data.size(),
&host, info, &count));
EXPECT_EQ(nullptr, host);
pkt.answers_.clear();
pkt.add_answer(new DNSARR("example.com", 100, {0x02, 0x03, 0x04, 0x05}));
// No answer.
pkt.answers_.clear();
data = pkt.data();
EXPECT_EQ(ARES_ENODATA, ares_parse_a_reply(data.data(), data.size(),
&host, info, &count));
EXPECT_EQ(nullptr, host);
pkt.add_answer(new DNSARR("example.com", 100, {0x02, 0x03, 0x04, 0x05}));
// Truncated packets.
data = pkt.data();
for (size_t len = 1; len < data.size(); len++) {
EXPECT_EQ(ARES_EBADRESP, ares_parse_a_reply(data.data(), len,
&host, info, &count));
EXPECT_EQ(nullptr, host);
EXPECT_EQ(ARES_EBADRESP, ares_parse_a_reply(data.data(), len,
nullptr, info, &count));
}
}
TEST_F(LibraryTest, ParseAReplyAllocFail) {
DNSPacket pkt;
pkt.set_qid(0x1234).set_response().set_aa()
.add_question(new DNSQuestion("example.com", ns_t_a))
.add_answer(new DNSCnameRR("example.com", 300, "c.example.com"))
.add_answer(new DNSARR("c.example.com", 500, {0x02, 0x03, 0x04, 0x05}));
std::vector<byte> data = pkt.data();
struct hostent *host = nullptr;
struct ares_addrttl info[2];
int count = 2;
for (int ii = 1; ii <= 8; ii++) {
ClearFails();
SetAllocFail(ii);
EXPECT_EQ(ARES_ENOMEM, ares_parse_a_reply(data.data(), data.size(),
&host, info, &count)) << ii;
EXPECT_EQ(nullptr, host);
}
}
} // namespace test
} // namespace ares
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