| // Copyright (c) 2011 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "net/dns/dns_response.h" |
| |
| #include "base/bind.h" |
| #include "base/rand_util.h" |
| #include "net/base/dns_util.h" |
| #include "net/base/net_errors.h" |
| #include "net/base/io_buffer.h" |
| #include "net/dns/dns_query.h" |
| #include "testing/gtest/include/gtest/gtest.h" |
| |
| namespace net { |
| |
| // DNS response consists of a header followed by a question followed by |
| // answer. Header format, question format and response format are |
| // described below. For the meaning of specific fields, please see RFC |
| // 1035. |
| |
| // Header format. |
| // 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 | |
| // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ |
| |
| // Question format. |
| // 1 1 1 1 1 1 |
| // 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 |
| // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ |
| // | | |
| // / QNAME / |
| // / / |
| // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ |
| // | QTYPE | |
| // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ |
| // | QCLASS | |
| // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ |
| |
| // Answser format. |
| // 1 1 1 1 1 1 |
| // 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 |
| // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ |
| // | | |
| // / / |
| // / NAME / |
| // | | |
| // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ |
| // | TYPE | |
| // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ |
| // | CLASS | |
| // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ |
| // | TTL | |
| // | | |
| // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ |
| // | RDLENGTH | |
| // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--| |
| // / RDATA / |
| // / / |
| // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ |
| |
| // TODO(agayev): add more thorough tests. |
| TEST(DnsResponseTest, ResponseWithCnameA) { |
| const std::string kQname("\012codereview\010chromium\003org", 25); |
| DnsQuery q1(kQname, kDNS_A, base::Bind(&base::RandInt)); |
| |
| uint8 id_hi = q1.id() >> 8, id_lo = q1.id() & 0xff; |
| |
| uint8 ip[] = { // codereview.chromium.org resolves to |
| 0x4a, 0x7d, 0x5f, 0x79 // 74.125.95.121 |
| }; |
| |
| IPAddressList expected_ips; |
| expected_ips.push_back(IPAddressNumber(ip, ip + arraysize(ip))); |
| |
| uint8 response_data[] = { |
| // Header |
| id_hi, id_lo, // ID |
| 0x81, 0x80, // Standard query response, no error |
| 0x00, 0x01, // 1 question |
| 0x00, 0x02, // 2 RRs (answers) |
| 0x00, 0x00, // 0 authority RRs |
| 0x00, 0x00, // 0 additional RRs |
| |
| // Question |
| 0x0a, 0x63, 0x6f, 0x64, // This part is echoed back from the |
| 0x65, 0x72, 0x65, 0x76, // respective query. |
| 0x69, 0x65, 0x77, 0x08, |
| 0x63, 0x68, 0x72, 0x6f, |
| 0x6d, 0x69, 0x75, 0x6d, |
| 0x03, 0x6f, 0x72, 0x67, |
| 0x00, |
| 0x00, 0x01, |
| 0x00, 0x01, |
| |
| // Answer 1 |
| 0xc0, 0x0c, // NAME is a pointer to name in Question section. |
| 0x00, 0x05, // TYPE is CNAME. |
| 0x00, 0x01, // CLASS is IN. |
| 0x00, 0x01, // TTL (4 bytes) is 20 hours, 47 minutes, 48 seconds. |
| 0x24, 0x74, |
| 0x00, 0x12, // RDLENGTH is 18 bytse. |
| 0x03, 0x67, 0x68, 0x73, // ghs.l.google.com in DNS format. |
| 0x01, 0x6c, 0x06, 0x67, |
| 0x6f, 0x6f, 0x67, 0x6c, |
| 0x65, 0x03, 0x63, 0x6f, |
| 0x6d, 0x00, |
| |
| // Answer 2 |
| 0xc0, 0x35, // NAME is a pointer to name in Question section. |
| 0x00, 0x01, // TYPE is A. |
| 0x00, 0x01, // CLASS is IN. |
| 0x00, 0x00, // TTL (4 bytes) is 53 seconds. |
| 0x00, 0x35, |
| 0x00, 0x04, // RDLENGTH is 4 bytes. |
| ip[0], ip[1], ip[2], ip[3], // RDATA is the IP. |
| }; |
| |
| // Create a response object and simulate reading into it. |
| DnsResponse r1(&q1); |
| memcpy(r1.io_buffer()->data(), &response_data[0], |
| r1.io_buffer()->size()); |
| |
| // Verify resolved IPs. |
| int response_size = arraysize(response_data); |
| IPAddressList actual_ips; |
| EXPECT_EQ(OK, r1.Parse(response_size, &actual_ips)); |
| EXPECT_EQ(expected_ips, actual_ips); |
| } |
| |
| } // namespace net |