Differential D4418 Diff 16627 src/seeder/test/dns_tests.cpp

Changeset View

Standalone View

src/seeder/test/dns_tests.cpp

This file was added.

				// Copyright (c) 2019 The Bitcoin developers
				// Distributed under the MIT software license, see the accompanying
				// file COPYING or http://www.opensource.org/licenses/mit-license.php.

				#include <seeder/dns.h>

				#include <string>
				#include <vector>

				#include <boost/test/unit_test.hpp>

				BOOST_AUTO_TEST_SUITE(dns_tests)

				static const int MAX_QUERY_NAME_LENGTH = 255;
				// Max size of the null-terminated buffer parse_name() writes to.
				static const int MAX_QUERY_NAME_BUFFER_LENGTH = MAX_QUERY_NAME_LENGTH + 1;
				static const uint8_t END_OF_NAME_FIELD = 0;

				// Builds the name field of the question section of a DNS query
				static std::vector<uint8_t>
				CreateDNSQuestionNameField(const std::string &queryName) {
				std::vector<uint8_t> nameField;
				size_t i = 0;
				size_t labelIndex = 0;
				while (i < queryName.size()) {
				if (queryName[i] == '.') {
				// Push the length of the label and then the label
				nameField.push_back(i - labelIndex);
				while (labelIndex < i) {
				nameField.push_back(queryName[labelIndex]);
				labelIndex++;
				}
				labelIndex = i + 1;
				}
				i++;
				}
				// Push the length of the label and then the label
				nameField.push_back(i - labelIndex);
				while (labelIndex < i) {
				nameField.push_back(queryName[labelIndex]);
				labelIndex++;
				}
				nameField.push_back(END_OF_NAME_FIELD);

				return nameField;
				}

				static void CheckParseName(const std::string &queryName) {
				std::vector<uint8_t> nameField = CreateDNSQuestionNameField(queryName);

				// Test when name field is too short to reach null-terminator
				for (size_t nameFieldEndIndex = 0; nameFieldEndIndex < nameField.size();
				nameFieldEndIndex++) {
				std::vector<char> parsedQueryName(MAX_QUERY_NAME_BUFFER_LENGTH, 0);
				const uint8_t *nameFieldBegin = nameField.data();
				int ret = parse_name(
				&nameFieldBegin, nameFieldBegin + nameFieldEndIndex,
				nameField.data(), parsedQueryName.data(), parsedQueryName.size());

				BOOST_CHECK(ret != 0);
				}

				// Test when the buffer size is too small
				size_t outputBufferSize = 1;
				while (outputBufferSize <= queryName.size()) {
				std::vector<char> parsedQueryName(outputBufferSize, 0);
				const uint8_t *nameFieldBegin = nameField.data();
				int ret = parse_name(&nameFieldBegin, nameFieldBegin + nameField.size(),
				nameField.data(), parsedQueryName.data(),
				parsedQueryName.size());
				BOOST_CHECK(ret != 0);
				outputBufferSize++;
				}

				// Happy path
				while (outputBufferSize <= MAX_QUERY_NAME_BUFFER_LENGTH) {
				std::vector<char> parsedQueryName(outputBufferSize, 0);
				const uint8_t *nameFieldBegin = nameField.data();
				int ret = parse_name(&nameFieldBegin, nameFieldBegin + nameField.size(),
				nameField.data(), parsedQueryName.data(),
				parsedQueryName.size());
				BOOST_CHECK_EQUAL(ret, 0);
				BOOST_CHECK_EQUAL(parsedQueryName.data(), queryName);
				outputBufferSize++;
				}
				}

				BOOST_AUTO_TEST_CASE(parse_name_tests) {
				CheckParseName("www.domain.com");
				CheckParseName("domain.com");
				CheckParseName("sub1.sub2.domain.co.uk");
				// Shortest valid domain name is 1 char followed by the extension
				CheckParseName("a.co");
				// Domain name with valid non-alphanumeric character
				CheckParseName("my-domain.com");
				}

				BOOST_AUTO_TEST_SUITE_END()