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/*
* Copyright (c) 2020, Fei Wu <f.eiwu@yahoo.com>
* Copyright (c) 2021, Brandon Pruitt <brapru@pm.me>
* Copyright (c) 2021, Maxime Friess <M4x1me@pm.me>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibCore/ArgsParser.h>
#include <LibCore/File.h>
#include <grp.h>
#include <pwd.h>
#include <unistd.h>
int main(int argc, char** argv)
{
if (pledge("stdio wpath rpath cpath fattr proc exec", nullptr) < 0) {
perror("pledge");
return 1;
}
if (unveil("/etc/", "rwc") < 0) {
perror("unveil");
return 1;
}
if (unveil("/bin/rm", "x") < 0) {
perror("unveil");
return 1;
}
char const* groupname = nullptr;
Core::ArgsParser args_parser;
args_parser.add_positional_argument(groupname, "Group name", "group");
args_parser.parse(argc, argv);
setgrent();
auto* g = getgrnam(groupname);
// Check if the group exists
if (!g) {
warnln("group {} does not exist", groupname);
return 6;
}
auto gid = g->gr_gid;
endgrent();
// Search if the group is the primary group of an user
setpwent();
struct passwd* pw;
for (pw = getpwent(); pw; pw = getpwent()) {
if (pw->pw_gid == gid)
break;
}
// If pw is not NULL it means we ended prematuraly, aka. the group was found as primary group of an user
if (pw) {
warnln("cannot remove the primary group of user '{}'", pw->pw_name);
endpwent();
return 8;
}
endpwent();
// We can now safely delete the group
// Create a temporary group file
char temp_group[] = "/etc/group.XXXXXX";
auto unlink_temp_files = [&] {
if (unlink(temp_group) < 0)
perror("unlink");
};
ArmedScopeGuard unlink_temp_files_guard = [&] {
unlink_temp_files();
};
auto temp_group_fd = mkstemp(temp_group);
if (temp_group_fd == -1) {
perror("failed to create temporary group file");
return 1;
}
FILE* temp_group_file = fdopen(temp_group_fd, "w");
if (!temp_group_file) {
perror("fdopen");
return 1;
}
setgrent();
for (auto* gr = getgrent(); gr; gr = getgrent()) {
if (gr->gr_gid != gid) {
if (putgrent(gr, temp_group_file) != 0) {
perror("failed to put an entry in the temporary group file");
return 1;
}
}
}
endgrent();
if (fclose(temp_group_file)) {
perror("fclose");
return 1;
}
if (chmod(temp_group, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH)) {
perror("chmod");
return 1;
}
if (rename(temp_group, "/etc/group") < 0) {
perror("failed to rename the temporary group file");
return 1;
}
unlink_temp_files_guard.disarm();
return 0;
}
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