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-rw-r--r--Services/LookupServer/LookupServer.cpp278
1 files changed, 0 insertions, 278 deletions
diff --git a/Services/LookupServer/LookupServer.cpp b/Services/LookupServer/LookupServer.cpp
deleted file mode 100644
index 16761ec7e4..0000000000
--- a/Services/LookupServer/LookupServer.cpp
+++ /dev/null
@@ -1,278 +0,0 @@
-/*
- * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- * 1. Redistributions of source code must retain the above copyright notice, this
- * list of conditions and the following disclaimer.
- *
- * 2. Redistributions in binary form must reproduce the above copyright notice,
- * this list of conditions and the following disclaimer in the documentation
- * and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
- * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
- * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include "LookupServer.h"
-#include "DNSRequest.h"
-#include "DNSResponse.h"
-#include <AK/ByteBuffer.h>
-#include <AK/HashMap.h>
-#include <AK/String.h>
-#include <AK/StringBuilder.h>
-#include <LibCore/ConfigFile.h>
-#include <LibCore/File.h>
-#include <LibCore/LocalServer.h>
-#include <LibCore/LocalSocket.h>
-#include <LibCore/UDPSocket.h>
-#include <stdio.h>
-#include <sys/time.h>
-#include <unistd.h>
-
-//#define LOOKUPSERVER_DEBUG
-
-LookupServer::LookupServer()
-{
- auto config = Core::ConfigFile::get_for_system("LookupServer");
- dbgln("Using network config file at {}", config->file_name());
- m_nameservers = config->read_entry("DNS", "Nameservers", "1.1.1.1,1.0.0.1").split(',');
-
- load_etc_hosts();
-
- m_local_server = Core::LocalServer::construct(this);
- m_local_server->on_ready_to_accept = [this]() {
- auto socket = m_local_server->accept();
- socket->on_ready_to_read = [this, socket]() {
- service_client(socket);
- RefPtr<Core::LocalSocket> keeper = socket;
- const_cast<Core::LocalSocket&>(*socket).on_ready_to_read = [] {};
- };
- };
- bool ok = m_local_server->take_over_from_system_server();
- ASSERT(ok);
-}
-
-void LookupServer::load_etc_hosts()
-{
- auto file = Core::File::construct("/etc/hosts");
- if (!file->open(Core::IODevice::ReadOnly))
- return;
- while (!file->eof()) {
- auto line = file->read_line(1024);
- if (line.is_empty())
- break;
- auto fields = line.split('\t');
-
- auto sections = fields[0].split('.');
- IPv4Address addr {
- (u8)atoi(sections[0].characters()),
- (u8)atoi(sections[1].characters()),
- (u8)atoi(sections[2].characters()),
- (u8)atoi(sections[3].characters()),
- };
-
- auto name = fields[1];
- m_etc_hosts.set(name, addr.to_string());
-
- IPv4Address reverse_addr {
- (u8)atoi(sections[3].characters()),
- (u8)atoi(sections[2].characters()),
- (u8)atoi(sections[1].characters()),
- (u8)atoi(sections[0].characters()),
- };
- StringBuilder builder;
- builder.append(reverse_addr.to_string());
- builder.append(".in-addr.arpa");
- m_etc_hosts.set(builder.to_string(), name);
- }
-}
-
-void LookupServer::service_client(RefPtr<Core::LocalSocket> socket)
-{
- u8 client_buffer[1024];
- int nrecv = socket->read(client_buffer, sizeof(client_buffer) - 1);
- if (nrecv < 0) {
- perror("read");
- return;
- }
-
- client_buffer[nrecv] = '\0';
-
- char lookup_type = client_buffer[0];
- if (lookup_type != 'L' && lookup_type != 'R') {
- dbgln("Invalid lookup_type '{}'", lookup_type);
- return;
- }
- auto hostname = String((const char*)client_buffer + 1, nrecv - 1, Chomp);
-#ifdef LOOKUPSERVER_DEBUG
- dbgln("Got request for '{}'", hostname);
-#endif
-
- Vector<String> responses;
-
- if (auto known_host = m_etc_hosts.get(hostname); known_host.has_value()) {
- responses.append(known_host.value());
- } else if (!hostname.is_empty()) {
- for (auto& nameserver : m_nameservers) {
-#ifdef LOOKUPSERVER_DEBUG
- dbgln("Doing lookup using nameserver '{}'", nameserver);
-#endif
- bool did_get_response = false;
- int retries = 3;
- do {
- if (lookup_type == 'L')
- responses = lookup(hostname, nameserver, did_get_response, T_A);
- else if (lookup_type == 'R')
- responses = lookup(hostname, nameserver, did_get_response, T_PTR);
- if (did_get_response)
- break;
- } while (--retries);
- if (!responses.is_empty()) {
- break;
- } else {
- if (!did_get_response)
- dbgln("Never got a response from '{}', trying next nameserver", nameserver);
- else
- dbgln("Received response from '{}' but no result(s), trying next nameserver", nameserver);
- }
- }
- if (responses.is_empty()) {
- fprintf(stderr, "LookupServer: Tried all nameservers but never got a response :(\n");
- return;
- }
- }
-
- if (responses.is_empty()) {
- int nsent = socket->write("Not found.\n");
- if (nsent < 0)
- perror("write");
- return;
- }
- for (auto& response : responses) {
- auto line = String::format("%s\n", response.characters());
- int nsent = socket->write(line);
- if (nsent < 0) {
- perror("write");
- break;
- }
- }
-}
-
-Vector<String> LookupServer::lookup(const String& hostname, const String& nameserver, bool& did_get_response, unsigned short record_type, ShouldRandomizeCase should_randomize_case)
-{
- if (auto it = m_lookup_cache.find(hostname); it != m_lookup_cache.end()) {
- auto& cached_lookup = it->value;
- if (cached_lookup.question.record_type() == record_type) {
- Vector<String> responses;
- for (auto& cached_answer : cached_lookup.answers) {
-#ifdef LOOKUPSERVER_DEBUG
- dbgln("Cache hit: {} -> {}, expired: {}", hostname, cached_answer.record_data(), cached_answer.has_expired());
-#endif
- if (!cached_answer.has_expired())
- responses.append(cached_answer.record_data());
- }
- if (!responses.is_empty())
- return responses;
- }
- m_lookup_cache.remove(it);
- }
-
- DNSRequest request;
- request.add_question(hostname, record_type, should_randomize_case);
-
- auto buffer = request.to_byte_buffer();
-
- auto udp_socket = Core::UDPSocket::construct();
- udp_socket->set_blocking(true);
-
- struct timeval timeout {
- 1, 0
- };
-
- int rc = setsockopt(udp_socket->fd(), SOL_SOCKET, SO_RCVTIMEO, &timeout, sizeof(timeout));
- if (rc < 0) {
- perror("setsockopt(SOL_SOCKET, SO_RCVTIMEO)");
- return {};
- }
-
- if (!udp_socket->connect(nameserver, 53))
- return {};
-
- if (!udp_socket->write(buffer))
- return {};
-
- u8 response_buffer[4096];
- int nrecv = udp_socket->read(response_buffer, sizeof(response_buffer));
- if (nrecv == 0)
- return {};
-
- did_get_response = true;
-
- auto o_response = DNSResponse::from_raw_response(response_buffer, nrecv);
- if (!o_response.has_value())
- return {};
-
- auto& response = o_response.value();
-
- if (response.id() != request.id()) {
- dbgln("LookupServer: ID mismatch ({} vs {}) :(", response.id(), request.id());
- return {};
- }
-
- if (response.code() == DNSResponse::Code::REFUSED) {
- if (should_randomize_case == ShouldRandomizeCase::Yes) {
- // Retry with 0x20 case randomization turned off.
- return lookup(hostname, nameserver, did_get_response, record_type, ShouldRandomizeCase::No);
- }
- return {};
- }
-
- if (response.question_count() != request.question_count()) {
- dbgln("LookupServer: Question count ({} vs {}) :(", response.question_count(), request.question_count());
- return {};
- }
-
- for (size_t i = 0; i < request.question_count(); ++i) {
- auto& request_question = request.questions()[i];
- auto& response_question = response.questions()[i];
- if (request_question != response_question) {
- dbgln("Request and response questions do not match");
- dbgln(" Request: name=_{}_, type={}, class={}", request_question.name(), response_question.record_type(), response_question.class_code());
- dbgln(" Response: name=_{}_, type={}, class={}", response_question.name(), response_question.record_type(), response_question.class_code());
- return {};
- }
- }
-
- if (response.answer_count() < 1) {
- dbgln("LookupServer: Not enough answers ({}) :(", response.answer_count());
- return {};
- }
-
- Vector<String, 8> responses;
- Vector<DNSAnswer, 8> cacheable_answers;
- for (auto& answer : response.answers()) {
- if (answer.type() != T_A)
- continue;
- responses.append(answer.record_data());
- if (!answer.has_expired())
- cacheable_answers.append(answer);
- }
-
- if (!cacheable_answers.is_empty()) {
- if (m_lookup_cache.size() >= 256)
- m_lookup_cache.remove(m_lookup_cache.begin());
- m_lookup_cache.set(hostname, { request.questions()[0], move(cacheable_answers) });
- }
- return responses;
-}
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