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/*
* Copyright (c) 2019-2020, Fei Wu <f.eiwu@yahoo.com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <AK/String.h>
#include <AK/StringBuilder.h>
#include <LibCore/ArgsParser.h>
#include <ctype.h>
#include <dirent.h>
#include <errno.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
int main(int argc, char** argv)
{
const char* username = nullptr;
bool remove_home = false;
Core::ArgsParser args_parser;
args_parser.add_option(remove_home, "Remove home directory", "remove", 'r');
args_parser.add_positional_argument(username, "Login user identity (username)", "login");
args_parser.parse(argc, argv);
char temp_filename[] = "/etc/passwd.XXXXXX";
auto fd = mkstemp(temp_filename);
if (fd == -1) {
perror("failed to create temporary file");
return 1;
}
FILE* temp_file = fdopen(fd, "w");
if (!temp_file) {
perror("fdopen");
if (unlink(temp_filename) < 0) {
perror("unlink");
}
return 1;
}
bool user_exists = false;
String home_directory;
int rc = 0;
setpwent();
for (auto* pw = getpwent(); pw; pw = getpwent()) {
if (strcmp(pw->pw_name, username)) {
if (putpwent(pw, temp_file) != 0) {
perror("failed to put an entry in the temporary passwd file");
rc = 1;
break;
}
} else {
user_exists = true;
if (remove_home)
home_directory = pw->pw_dir;
}
}
endpwent();
if (fclose(temp_file)) {
perror("fclose");
if (!rc)
rc = 1;
}
if (rc == 0 && !user_exists) {
fprintf(stderr, "specified user doesn't exist\n");
rc = 6;
}
if (rc == 0 && chmod(temp_filename, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH)) {
perror("chmod");
rc = 1;
}
if (rc == 0 && rename(temp_filename, "/etc/passwd") < 0) {
perror("failed to rename the temporary passwd file");
rc = 1;
}
if (rc) {
if (unlink(temp_filename) < 0) {
perror("unlink");
}
return rc;
}
if (remove_home) {
if (home_directory == "/") {
fprintf(stderr, "home directory is /, not deleted!\n");
return 12;
}
if (access(home_directory.characters(), F_OK) != -1) {
auto child = fork();
if (child < 0) {
perror("fork");
return 12;
}
if (!child) {
int rc = execl("/bin/rm", "rm", "-r", home_directory.characters(), nullptr);
ASSERT(rc < 0);
perror("execl");
exit(127);
}
int wstatus;
if (waitpid(child, &wstatus, 0) < 0) {
perror("waitpid");
return 12;
}
if (WEXITSTATUS(wstatus)) {
fprintf(stderr, "failed to remove the home directory\n");
return 12;
}
}
}
return 0;
}
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