summaryrefslogtreecommitdiff
path: root/Userland/Utilities/useradd.cpp
blob: 627e1209f241e7bb53ae45c38f53dbae3602dff0 (plain)
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
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
/*
 * Copyright (c) 2019-2020, Jesse Buhagiar <jooster669@gmail.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 <LibCore/ArgsParser.h>
#include <ctype.h>
#include <pwd.h>
#include <stdio.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>

constexpr uid_t BASE_UID = 1000;
constexpr gid_t USERS_GID = 100;
constexpr const char* DEFAULT_SHELL = "/bin/Shell";

int main(int argc, char** argv)
{
    if (pledge("stdio wpath rpath cpath chown", nullptr) < 0) {
        perror("pledge");
        return 1;
    }

    const char* home_path = nullptr;
    int uid = 0;
    int gid = USERS_GID;
    bool create_home_dir = false;
    const char* password = "";
    const char* shell = DEFAULT_SHELL;
    const char* gecos = "";
    const char* username = nullptr;

    Core::ArgsParser args_parser;
    args_parser.add_option(home_path, "Home directory for the new user", "home-dir", 'd', "path");
    args_parser.add_option(uid, "User ID (uid) for the new user", "uid", 'u', "uid");
    args_parser.add_option(gid, "Group ID (gid) for the new user", "gid", 'g', "gid");
    args_parser.add_option(password, "Encrypted password of the new user", "password", 'p', "password");
    args_parser.add_option(create_home_dir, "Create home directory if it does not exist", "create-home", 'm');
    args_parser.add_option(shell, "Path to the default shell binary for the new user", "shell", 's', "path-to-shell");
    args_parser.add_option(gecos, "GECOS name of the new user", "gecos", 'n', "general-info");
    args_parser.add_positional_argument(username, "Login user identity (username)", "login");

    args_parser.parse(argc, argv);

    // Let's run a quick sanity check on username
    if (strpbrk(username, "\\/!@#$%^&*()~+=`:\n")) {
        fprintf(stderr, "invalid character in username, %s\n", username);
        return 1;
    }

    // Disallow names starting with _ and -
    if (username[0] == '_' || username[0] == '-' || !isalpha(username[0])) {
        fprintf(stderr, "invalid username, %s\n", username);
        return 1;
    }

    if (uid < 0) {
        fprintf(stderr, "invalid uid %d!\n", uid);
        return 3;
    }

    // First, let's sort out the uid for the user
    if (uid > 0) {
        if (getpwuid(static_cast<uid_t>(uid))) {
            fprintf(stderr, "uid %u already exists!\n", uid);
            return 4;
        }

    } else {
        for (uid = BASE_UID; getpwuid(static_cast<uid_t>(uid)); uid++) {
        }
    }

    if (gid < 0) {
        fprintf(stderr, "invalid gid %d\n", gid);
        return 3;
    }

    FILE* pwfile = fopen("/etc/passwd", "a");
    if (!pwfile) {
        perror("failed to open /etc/passwd");
        return 1;
    }

    String home;
    if (!home_path)
        home = String::format("/home/%s", username);
    else
        home = home_path;

    if (create_home_dir) {
        if (mkdir(home.characters(), 0700) < 0) {
            perror(String::format("failed to create directory %s", home.characters()).characters());
            return 12;
        }

        if (chown(home.characters(), static_cast<uid_t>(uid), static_cast<gid_t>(gid)) < 0) {
            perror(String::format("failed to chown %s to %u:%u", home.characters(), uid, gid).characters());

            if (rmdir(home.characters()) < 0) {
                perror(String::format("failed to rmdir %s", home.characters()).characters());
                return 12;
            }
            return 12;
        }
    }

    struct passwd p;
    p.pw_name = const_cast<char*>(username);
    p.pw_passwd = const_cast<char*>(password);
    p.pw_dir = const_cast<char*>(home.characters());
    p.pw_uid = static_cast<uid_t>(uid);
    p.pw_gid = static_cast<gid_t>(gid);
    p.pw_shell = const_cast<char*>(shell);
    p.pw_gecos = const_cast<char*>(gecos);

    if (putpwent(&p, pwfile) < 0) {
        perror("putpwent");
        return 1;
    }

    fclose(pwfile);

    return 0;
}