1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
|
/*
* 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>
* Copyright (c) 2022, Umut İnan Erdoğan <umutinanerdogan62@gmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibCore/ArgsParser.h>
#include <LibCore/File.h>
#include <LibCore/System.h>
#include <LibMain/Main.h>
#include <grp.h>
#include <pwd.h>
#include <unistd.h>
ErrorOr<int> serenity_main(Main::Arguments arguments)
{
TRY(Core::System::pledge("stdio wpath rpath cpath fattr proc exec"));
TRY(Core::System::unveil("/etc/", "rwc"));
TRY(Core::System::unveil("/bin/rm", "x"));
char const* groupname = nullptr;
Core::ArgsParser args_parser;
args_parser.add_positional_argument(groupname, "Group name", "group");
args_parser.parse(arguments);
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 prematurely, 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";
StringView temp_group_view { temp_group, strlen(temp_group) };
auto unlink_temp_files = [&] {
if (Core::System::unlink(temp_group_view).is_error())
perror("unlink");
};
ArmedScopeGuard unlink_temp_files_guard = [&] {
unlink_temp_files();
};
int temp_group_fd = TRY(Core::System::mkstemp(temp_group));
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;
}
TRY(Core::System::chmod(temp_group_view, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH));
TRY(Core::System::rename(temp_group_view, "/etc/group"sv));
unlink_temp_files_guard.disarm();
return 0;
}
|
