/*
* Copyright (C) 2007 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.
*/
#define TRACE_TAG TRANSPORT
#include "sysdeps.h"
#include "transport.h"
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <android-base/stringprintf.h>
#include <cutils/sockets.h>
#if !ADB_HOST
#include "cutils/properties.h"
#endif
#include "adb.h"
#include "adb_io.h"
#include "adb_utils.h"
#if ADB_HOST
// Android Wear has been using port 5601 in all of its documentation/tooling,
// but we search for emulators on ports [5554, 5555 + ADB_LOCAL_TRANSPORT_MAX].
// Avoid stomping on their port by limiting the number of emulators that can be
// connected.
#define ADB_LOCAL_TRANSPORT_MAX 16
ADB_MUTEX_DEFINE(local_transports_lock);
/* we keep a list of opened transports. The atransport struct knows to which
* local transport it is connected. The list is used to detect when we're
* trying to connect twice to a given local transport.
*/
static atransport* local_transports[ ADB_LOCAL_TRANSPORT_MAX ];
#endif /* ADB_HOST */
static int remote_read(apacket *p, atransport *t)
{
if(!ReadFdExactly(t->sfd, &p->msg, sizeof(amessage))){
D("remote local: read terminated (message)");
return -1;
}
if(check_header(p, t)) {
D("bad header: terminated (data)");
return -1;
}
if(!ReadFdExactly(t->sfd, p->data, p->msg.data_length)){
D("remote local: terminated (data)");
return -1;
}
if(check_data(p)) {
D("bad data: terminated (data)");
return -1;
}
return 0;
}
static int remote_write(apacket *p, atransport *t)
{
int length = p->msg.data_length;
if(!WriteFdExactly(t->sfd, &p->msg, sizeof(amessage) + length)) {
D("remote local: write terminated");
return -1;
}
return 0;
}
void local_connect(int port) {
std::string dummy;
local_connect_arbitrary_ports(port-1, port, &dummy);
}
int local_connect_arbitrary_ports(int console_port, int adb_port, std::string* error) {
int fd = -1;
#if ADB_HOST
if (find_emulator_transport_by_adb_port(adb_port) != nullptr) {
return -1;
}
const char *host = getenv("ADBHOST");
if (host) {
fd = network_connect(host, adb_port, SOCK_STREAM, 0, error);
}
#endif
if (fd < 0) {
fd = network_loopback_client(adb_port, SOCK_STREAM, error);
}
if (fd >= 0) {
D("client: connected on remote on fd %d", fd);
close_on_exec(fd);
disable_tcp_nagle(fd);
std::string serial = android::base::StringPrintf("emulator-%d", console_port);
if (register_socket_transport(fd, serial.c_str(), adb_port, 1) == 0) {
return 0;
}
adb_close(fd);
}
return -1;
}
#if ADB_HOST
static void client_socket_thread(void* x) {
adb_thread_setname("client_socket_thread");
D("transport: client_socket_thread() starting");
while (true) {
int port = DEFAULT_ADB_LOCAL_TRANSPORT_PORT;
int count = ADB_LOCAL_TRANSPORT_MAX;
// Try to connect to any number of running emulator instances.
for ( ; count > 0; count--, port += 2 ) {
local_connect(port);
}
sleep(1);
}
}
#else // ADB_HOST
static void server_socket_thread(void* arg) {
int serverfd, fd;
sockaddr_storage ss;
sockaddr *addrp = reinterpret_cast<sockaddr*>(&ss);
socklen_t alen;
int port = (int) (uintptr_t) arg;
adb_thread_setname("server socket");
D("transport: server_socket_thread() starting");
serverfd = -1;
for(;;) {
if(serverfd == -1) {
std::string error;
serverfd = network_inaddr_any_server(port, SOCK_STREAM, &error);
if(serverfd < 0) {
D("server: cannot bind socket yet: %s", error.c_str());
adb_sleep_ms(1000);
continue;
}
close_on_exec(serverfd);
}
alen = sizeof(ss);
D("server: trying to get new connection from %d", port);
fd = adb_socket_accept(serverfd, addrp, &alen);
if(fd >= 0) {
D("server: new connection on fd %d", fd);
close_on_exec(fd);
disable_tcp_nagle(fd);
register_socket_transport(fd, "host", port, 1);
}
}
D("transport: server_socket_thread() exiting");
}
/* This is relevant only for ADB daemon running inside the emulator. */
/*
* Redefine open and write for qemu_pipe.h that contains inlined references
* to those routines. We will redifine them back after qemu_pipe.h inclusion.
*/
#undef open
#undef write
#define open adb_open
#define write adb_write
#include <hardware/qemu_pipe.h>
#undef open
#undef write
#define open ___xxx_open
#define write ___xxx_write
/* A worker thread that monitors host connections, and registers a transport for
* every new host connection. This thread replaces server_socket_thread on
* condition that adbd daemon runs inside the emulator, and emulator uses QEMUD
* pipe to communicate with adbd daemon inside the guest. This is done in order
* to provide more robust communication channel between ADB host and guest. The
* main issue with server_socket_thread approach is that it runs on top of TCP,
* and thus is sensitive to network disruptions. For instance, the
* ConnectionManager may decide to reset all network connections, in which case
* the connection between ADB host and guest will be lost. To make ADB traffic
* independent from the network, we use here 'adb' QEMUD service to transfer data
* between the host, and the guest. See external/qemu/android/adb-*.* that
* implements the emulator's side of the protocol. Another advantage of using
* QEMUD approach is that ADB will be up much sooner, since it doesn't depend
* anymore on network being set up.
* The guest side of the protocol contains the following phases:
* - Connect with adb QEMUD service. In this phase a handle to 'adb' QEMUD service
* is opened, and it becomes clear whether or not emulator supports that
* protocol.
* - Wait for the ADB host to create connection with the guest. This is done by
* sending an 'accept' request to the adb QEMUD service, and waiting on
* response.
* - When new ADB host connection is accepted, the connection with adb QEMUD
* service is registered as the transport, and a 'start' request is sent to the
* adb QEMUD service, indicating that the guest is ready to receive messages.
* Note that the guest will ignore messages sent down from the emulator before
* the transport registration is completed. That's why we need to send the
* 'start' request after the transport is registered.
*/
static void qemu_socket_thread(void* arg) {
/* 'accept' request to the adb QEMUD service. */
static const char _accept_req[] = "accept";
/* 'start' request to the adb QEMUD service. */
static const char _start_req[] = "start";
/* 'ok' reply from the adb QEMUD service. */
static const char _ok_resp[] = "ok";
const int port = (int) (uintptr_t) arg;
int fd;
char tmp[256];
char con_name[32];
adb_thread_setname("qemu socket");
D("transport: qemu_socket_thread() starting");
/* adb QEMUD service connection request. */
snprintf(con_name, sizeof(con_name), "qemud:adb:%d", port);
/* Connect to the adb QEMUD service. */
fd = qemu_pipe_open(con_name);
if (fd < 0) {
/* This could be an older version of the emulator, that doesn't
* implement adb QEMUD service. Fall back to the old TCP way. */
D("adb service is not available. Falling back to TCP socket.");
adb_thread_create(server_socket_thread, arg);
return;
}
for(;;) {
/*
* Wait till the host creates a new connection.
*/
/* Send the 'accept' request. */
if (WriteFdExactly(fd, _accept_req, strlen(_accept_req))) {
/* Wait for the response. In the response we expect 'ok' on success,
* or 'ko' on failure. */
if (!ReadFdExactly(fd, tmp, 2) || memcmp(tmp, _ok_resp, 2)) {
D("Accepting ADB host connection has failed.");
adb_close(fd);
} else {
/* Host is connected. Register the transport, and start the
* exchange. */
std::string serial = android::base::StringPrintf("host-%d", fd);
register_socket_transport(fd, serial.c_str(), port, 1);
if (!WriteFdExactly(fd, _start_req, strlen(_start_req))) {
adb_close(fd);
}
}
/* Prepare for accepting of the next ADB host connection. */
fd = qemu_pipe_open(con_name);
if (fd < 0) {
D("adb service become unavailable.");
return;
}
} else {
D("Unable to send the '%s' request to ADB service.", _accept_req);
return;
}
}
D("transport: qemu_socket_thread() exiting");
return;
}
#endif // !ADB_HOST
void local_init(int port)
{
adb_thread_func_t func;
const char* debug_name = "";
#if ADB_HOST
func = client_socket_thread;
debug_name = "client";
#else
/* For the adbd daemon in the system image we need to distinguish
* between the device, and the emulator. */
char is_qemu[PROPERTY_VALUE_MAX];
property_get("ro.kernel.qemu", is_qemu, "");
if (!strcmp(is_qemu, "1")) {
/* Running inside the emulator: use QEMUD pipe as the transport. */
func = qemu_socket_thread;
} else {
/* Running inside the device: use TCP socket as the transport. */
func = server_socket_thread;
}
debug_name = "server";
#endif // !ADB_HOST
D("transport: local %s init", debug_name);
if (!adb_thread_create(func, (void *) (uintptr_t) port)) {
fatal_errno("cannot create local socket %s thread", debug_name);
}
}
static void remote_kick(atransport *t)
{
int fd = t->sfd;
t->sfd = -1;
adb_shutdown(fd);
adb_close(fd);
#if ADB_HOST
int nn;
adb_mutex_lock( &local_transports_lock );
for (nn = 0; nn < ADB_LOCAL_TRANSPORT_MAX; nn++) {
if (local_transports[nn] == t) {
local_transports[nn] = NULL;
break;
}
}
adb_mutex_unlock( &local_transports_lock );
#endif
}
static void remote_close(atransport *t)
{
int fd = t->sfd;
if (fd != -1) {
t->sfd = -1;
adb_close(fd);
}
}
#if ADB_HOST
/* Only call this function if you already hold local_transports_lock. */
atransport* find_emulator_transport_by_adb_port_locked(int adb_port)
{
int i;
for (i = 0; i < ADB_LOCAL_TRANSPORT_MAX; i++) {
if (local_transports[i] && local_transports[i]->adb_port == adb_port) {
return local_transports[i];
}
}
return NULL;
}
atransport* find_emulator_transport_by_adb_port(int adb_port)
{
adb_mutex_lock( &local_transports_lock );
atransport* result = find_emulator_transport_by_adb_port_locked(adb_port);
adb_mutex_unlock( &local_transports_lock );
return result;
}
/* Only call this function if you already hold local_transports_lock. */
int get_available_local_transport_index_locked()
{
int i;
for (i = 0; i < ADB_LOCAL_TRANSPORT_MAX; i++) {
if (local_transports[i] == NULL) {
return i;
}
}
return -1;
}
int get_available_local_transport_index()
{
adb_mutex_lock( &local_transports_lock );
int result = get_available_local_transport_index_locked();
adb_mutex_unlock( &local_transports_lock );
return result;
}
#endif
int init_socket_transport(atransport *t, int s, int adb_port, int local)
{
int fail = 0;
t->SetKickFunction(remote_kick);
t->close = remote_close;
t->read_from_remote = remote_read;
t->write_to_remote = remote_write;
t->sfd = s;
t->sync_token = 1;
t->connection_state = kCsOffline;
t->type = kTransportLocal;
t->adb_port = 0;
#if ADB_HOST
if (local) {
adb_mutex_lock( &local_transports_lock );
{
t->adb_port = adb_port;
atransport* existing_transport =
find_emulator_transport_by_adb_port_locked(adb_port);
int index = get_available_local_transport_index_locked();
if (existing_transport != NULL) {
D("local transport for port %d already registered (%p)?",
adb_port, existing_transport);
fail = -1;
} else if (index < 0) {
// Too many emulators.
D("cannot register more emulators. Maximum is %d",
ADB_LOCAL_TRANSPORT_MAX);
fail = -1;
} else {
local_transports[index] = t;
}
}
adb_mutex_unlock( &local_transports_lock );
}
#endif
return fail;
}