sandboxed-api/sandboxed_api/sandbox2/fork_client.cc
Christian Blichmann b74cf8839b Minor ForkClient improvements
- Use a `constexpr inline` string constant for the forkserver env var
- Add annotation for the comms channel mutex

PiperOrigin-RevId: 335395005
Change-Id: Ic058c19c3704f182aa7ed7b8e8964b2fc5082800
2020-10-05 05:10:16 -07:00

76 lines
2.5 KiB
C++

// Copyright 2020 Google LLC
//
// 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 "sandboxed_api/sandbox2/fork_client.h"
#include "sandboxed_api/sandbox2/comms.h"
#include "sandboxed_api/sandbox2/forkserver.pb.h"
#include "sandboxed_api/util/raw_logging.h"
namespace sandbox2 {
pid_t ForkClient::SendRequest(const ForkRequest& request, int exec_fd,
int comms_fd, int user_ns_fd, pid_t* init_pid) {
// Acquire the channel ownership for this request (transaction).
absl::MutexLock l(&comms_mutex_);
if (!comms_->SendProtoBuf(request)) {
SAPI_RAW_LOG(ERROR, "Sending PB to the ForkServer failed");
return -1;
}
SAPI_RAW_CHECK(comms_fd != -1, "comms_fd was not properly set up");
if (!comms_->SendFD(comms_fd)) {
SAPI_RAW_LOG(ERROR, "Sending Comms FD (%d) to the ForkServer failed",
comms_fd);
return -1;
}
if (request.mode() == FORKSERVER_FORK_EXECVE ||
request.mode() == FORKSERVER_FORK_EXECVE_SANDBOX) {
SAPI_RAW_CHECK(exec_fd != -1, "exec_fd cannot be -1 in execve mode");
if (!comms_->SendFD(exec_fd)) {
SAPI_RAW_LOG(ERROR, "Sending Exec FD (%d) to the ForkServer failed",
exec_fd);
return -1;
}
}
if (request.mode() == FORKSERVER_FORK_JOIN_SANDBOX_UNWIND) {
SAPI_RAW_CHECK(user_ns_fd != -1, "user_ns_fd cannot be -1 in unwind mode");
if (!comms_->SendFD(user_ns_fd)) {
SAPI_RAW_LOG(ERROR, "Sending user ns FD (%d) to the ForkServer failed",
user_ns_fd);
return -1;
}
}
int32_t pid;
// Receive init process ID.
if (!comms_->RecvInt32(&pid)) {
SAPI_RAW_LOG(ERROR, "Receiving init PID from the ForkServer failed");
return -1;
}
if (init_pid) {
*init_pid = static_cast<pid_t>(pid);
}
// Receive sandboxee process ID.
if (!comms_->RecvInt32(&pid)) {
SAPI_RAW_LOG(ERROR, "Receiving sandboxee PID from the ForkServer failed");
return -1;
}
return static_cast<pid_t>(pid);
}
} // namespace sandbox2