blob: 68ac18e7d1f608900c092bf8f031c78dd91fe7c7 [file] [log] [blame]
* Copyright (C) 2017 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
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* See the License for the specific language governing permissions and
* limitations under the License.
/* Utility that uses an adb connection as the login shell. */
#include "host/libs/config/cuttlefish_config.h"
#include <array>
#include <cassert>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <string>
#include <vector>
#include <unistd.h>
// Many of our users interact with CVDs via ssh. They expect to be able to
// get an Android shell (as opposed to the host shell) with a single command.
// Our goals are to:
// * Allow the user to select which CVD to connect to
// * Avoid modifications to the host-side sshd and the protocol
// We accomplish this by using specialized accounts: vsoc-## and cvd-## and
// specific Android serial numbers:
// The vsoc-01 account provides a host-side shell that controls the first CVD
// The cvd-01 account is connected to the Andorid shell of the first CVD
// The first CVD has a serial number of CUTTLEFISHCVD01
// The code in the commands/launch directory also follows these conventions by
// default.
namespace {
std::string VsocUser() {
const char* user_cstring = std::getenv("USER");
assert(user_cstring != nullptr);
std::string user(user_cstring);
std::string cvd_prefix = "cvd-";
if (user.find(cvd_prefix) == 0) {
user.replace(0, cvd_prefix.size(), vsoc::kVsocUserPrefix);
return user;
std::string CuttlefishConfigLocation() {
return std::string("/home/") + VsocUser() +
void SetCuttlefishConfigEnv() {
setenv(vsoc::kCuttlefishConfigEnvVarName, CuttlefishConfigLocation().c_str(),
} // namespace
int main(int argc, char* argv[]) {
auto instance = vsoc::CuttlefishConfig::Get()->adb_device_name();
std::vector<char*> new_argv = {
const_cast<char*>("/usr/bin/adb"), const_cast<char*>("-s"),
const_cast<char*>(instance.c_str()), const_cast<char*>("shell"),
// Some important data is lost before this point, and there are
// no great recovery options:
// * ssh with no arguments comes in with 1 arg of -adbshell. The command
// given above does the right thing if we don't invoke the shell.
if (argc == 1) {
new_argv.back() = nullptr;
// * simple shell commands come in with a -c and a single string. The
// problem here is that adb doesn't preserve spaces, so we need
// to do additional escaping. The best compromise seems to be to
// throw double quotes around each string.
for (int i = 1; i < argc; ++i) {
size_t buf_size = std::strlen(argv[i]) + 4;
new_argv.push_back(new char[buf_size]);
std::snprintf(new_argv.back(), buf_size, "\"%s\"", argv[i]);
// * scp seems to be pathologically broken when paths contain spaces.
// spaces aren't properly escaped by gcloud, so scp will fail with
// "scp: with ambiguous target." We might be able to fix this with
// some creative parsing of the arguments, but that seems like
// overkill.
// This never should happen
return 2;