blob: 1d91458b5a6885e5073bfe70c3f5d078ad010163 [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
*
* 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.
*/
/*
* Tool to create a directory with the right SELinux context applied, or
* apply the context if it's absent. Also fixes mode, uid, gid.
*/
#include <string>
#include <vector>
#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <android-base/logging.h>
#include <cutils/fs.h>
#include <selinux/android.h>
void usage(const char* progname) {
fprintf(stderr, "Usage: %s --mode MODE --uid UID --gid GID -- <path>\n", progname);
}
bool small_int(const std::string& s) {
return !s.empty() && s.size() < 7 && s.find_first_not_of("0123456789") == std::string::npos;
}
int main(int argc, const char* const argv[]) {
setenv("ANDROID_LOG_TAGS", "*:v", 1);
android::base::InitLogging(const_cast<char**>(argv));
std::vector<std::string> args(argv + 1, argv + argc);
// Enforce exact format of arguments. You can always loosen but you can never tighten :)
if (args.size() != 8 || args[0] != "--mode" || !small_int(args[1]) || args[2] != "--uid" ||
!small_int(args[3]) || args[4] != "--gid" || !small_int(args[5]) || args[6] != "--") {
usage(argv[0]);
return -1;
}
mode_t mode = (mode_t)stoi(args[1], nullptr, 8);
uid_t uid = (uid_t)stoi(args[3]);
gid_t gid = (gid_t)stoi(args[5]);
const char* path = args[7].c_str();
struct selabel_handle* sehandle = selinux_android_file_context_handle();
char* secontext = nullptr;
if (sehandle) {
if (selabel_lookup(sehandle, &secontext, path, S_IFDIR) == 0) {
setfscreatecon(secontext);
}
}
if (fs_prepare_dir(path, mode, uid, gid) != 0) {
return -1;
}
if (secontext) {
char* oldsecontext = nullptr;
if (lgetfilecon(path, &oldsecontext) < 0) {
PLOG(ERROR) << "Unable to read secontext for: " << path;
return -1;
}
if (strcmp(secontext, oldsecontext) != 0) {
LOG(INFO) << "Relabelling from " << oldsecontext << " to " << secontext << ": " << path;
if (lsetfilecon(path, secontext) != 0) {
PLOG(ERROR) << "Relabelling failed for: " << path;
}
}
}
return 0;
}