Make ADBD announce its presence over mDNS

We now request mdnsd from adb and register a service of type _adb._tcp
for clients to connect to.

Test: Verified service appears in avahi-browse
Bug: 28074466
(cherry picked from 379ac414e4d9f53388d903913022a55695292775)

Change-Id: Ie871b9c8b40e86063cc1e68e8f3e4290ead2d279
This commit is contained in:
Casey Dahlin 2016-05-06 16:19:13 -07:00
parent 5811a434fc
commit 6cd5e0b4ef
4 changed files with 123 additions and 2 deletions

View File

@ -325,6 +325,7 @@ LOCAL_CLANG := true
LOCAL_SRC_FILES := \
daemon/main.cpp \
daemon/mdns.cpp \
services.cpp \
file_sync_service.cpp \
framebuffer_service.cpp \
@ -372,6 +373,7 @@ LOCAL_STATIC_LIBRARIES := \
libcrypto_utils \
libcrypto \
libminijail \
libmdnssd \
libdebuggerd_handler \
include $(BUILD_EXECUTABLE)

View File

@ -45,6 +45,8 @@
#include "adb_utils.h"
#include "transport.h"
#include "mdns.h"
static const char* root_seclabel = nullptr;
static void drop_capabilities_bounding_set_if_needed(struct minijail *j) {
@ -140,6 +142,11 @@ static void drop_privileges(int server_port) {
}
}
static void setup_port(int port) {
local_init(port);
setup_mdns(port);
}
int adbd_main(int server_port) {
umask(0);
@ -188,10 +195,10 @@ int adbd_main(int server_port) {
if (sscanf(prop_port.c_str(), "%d", &port) == 1 && port > 0) {
D("using port=%d", port);
// Listen on TCP port specified by service.adb.tcp.port property.
local_init(port);
setup_port(port);
} else if (!is_usb) {
// Listen on default port.
local_init(DEFAULT_ADB_LOCAL_TRANSPORT_PORT);
setup_port(DEFAULT_ADB_LOCAL_TRANSPORT_PORT);
}
D("adbd_main(): pre init_jdwp()");

90
adb/daemon/mdns.cpp Normal file
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@ -0,0 +1,90 @@
/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "sysdeps.h"
#include <chrono>
#include <dns_sd.h>
#include <endian.h>
#include <mutex>
#include <unistd.h>
#include <android-base/logging.h>
#include <android-base/properties.h>
using namespace std::chrono_literals;
static std::mutex& mdns_lock = *new std::mutex();
static int port;
static DNSServiceRef mdns_ref;
static bool mdns_registered = false;
static void start_mdns() {
if (android::base::GetProperty("init.svc.mdnsd", "") == "running") {
return;
}
android::base::SetProperty("ctl.start", "mdnsd");
if (! android::base::WaitForProperty("init.svc.mdnsd", "running", 5s)) {
LOG(ERROR) << "Could not start mdnsd.";
}
}
static void mdns_callback(DNSServiceRef /*ref*/,
DNSServiceFlags /*flags*/,
DNSServiceErrorType errorCode,
const char* /*name*/,
const char* /*regtype*/,
const char* /*domain*/,
void* /*context*/) {
if (errorCode != kDNSServiceErr_NoError) {
LOG(ERROR) << "Encountered mDNS registration error ("
<< errorCode << ").";
}
}
static void setup_mdns_thread(void* /* unused */) {
start_mdns();
std::lock_guard<std::mutex> lock(mdns_lock);
auto error = DNSServiceRegister(&mdns_ref, 0, 0, nullptr, "_adb._tcp",
nullptr, nullptr, htobe16((uint16_t)port),
0, nullptr, mdns_callback, nullptr);
if (error != kDNSServiceErr_NoError) {
LOG(ERROR) << "Could not register mDNS service (" << error << ").";
mdns_registered = false;
}
mdns_registered = true;
}
static void teardown_mdns() {
std::lock_guard<std::mutex> lock(mdns_lock);
if (mdns_registered) {
DNSServiceRefDeallocate(mdns_ref);
}
}
void setup_mdns(int port_in) {
port = port_in;
adb_thread_create(setup_mdns_thread, nullptr, nullptr);
// TODO: Make this more robust against a hard kill.
atexit(teardown_mdns);
}

22
adb/daemon/mdns.h Normal file
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@ -0,0 +1,22 @@
/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef _DAEMON_MDNS_H_
#define _DAEMON_MDNS_H_
void setup_mdns(int port);
#endif // _DAEMON_MDNS_H_