blob: fd5b40bd4383280d57d2a83556c7374ccffd67a5
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * addgroup - add groups to /etc/group and /etc/gshadow |
4 | * |
5 | * Copyright (C) 1999 by Lineo, inc. and John Beppu |
6 | * Copyright (C) 1999,2000,2001 by John Beppu <beppu@codepoet.org> |
7 | * Copyright (C) 2007 by Tito Ragusa <farmatito@tiscali.it> |
8 | * |
9 | * Licensed under GPLv2 or later, see file LICENSE in this source tree. |
10 | * |
11 | */ |
12 | |
13 | //usage:#define addgroup_trivial_usage |
14 | //usage: "[-g GID] " IF_FEATURE_ADDUSER_TO_GROUP("[USER] ") "GROUP" |
15 | //usage:#define addgroup_full_usage "\n\n" |
16 | //usage: "Add a group " IF_FEATURE_ADDUSER_TO_GROUP("or add a user to a group") "\n" |
17 | //usage: "\n -g GID Group id" |
18 | //usage: "\n -S Create a system group" |
19 | |
20 | #include "libbb.h" |
21 | |
22 | #if CONFIG_LAST_SYSTEM_ID < CONFIG_FIRST_SYSTEM_ID |
23 | #error Bad LAST_SYSTEM_ID or FIRST_SYSTEM_ID in .config |
24 | #endif |
25 | |
26 | #define OPT_GID (1 << 0) |
27 | #define OPT_SYSTEM_ACCOUNT (1 << 1) |
28 | |
29 | /* We assume GID_T_MAX == INT_MAX */ |
30 | static void xgroup_study(struct group *g) |
31 | { |
32 | unsigned max = INT_MAX; |
33 | |
34 | /* Make sure gr_name is unused */ |
35 | if (getgrnam(g->gr_name)) { |
36 | bb_error_msg_and_die("%s '%s' in use", "group", g->gr_name); |
37 | /* these format strings are reused in adduser and addgroup */ |
38 | } |
39 | |
40 | /* if a specific gid is requested, the --system switch and */ |
41 | /* min and max values are overridden, and the range of valid */ |
42 | /* gid values is set to [0, INT_MAX] */ |
43 | if (!(option_mask32 & OPT_GID)) { |
44 | if (option_mask32 & OPT_SYSTEM_ACCOUNT) { |
45 | g->gr_gid = CONFIG_FIRST_SYSTEM_ID; |
46 | max = CONFIG_LAST_SYSTEM_ID; |
47 | } else { |
48 | g->gr_gid = CONFIG_LAST_SYSTEM_ID + 1; |
49 | max = 64999; |
50 | } |
51 | } |
52 | /* Check if the desired gid is free |
53 | * or find the first free one */ |
54 | while (1) { |
55 | if (!getgrgid(g->gr_gid)) { |
56 | return; /* found free group: return */ |
57 | } |
58 | if (option_mask32 & OPT_GID) { |
59 | /* -g N, cannot pick gid other than N: error */ |
60 | bb_error_msg_and_die("%s '%s' in use", "gid", itoa(g->gr_gid)); |
61 | /* this format strings is reused in adduser and addgroup */ |
62 | } |
63 | if (g->gr_gid == max) { |
64 | /* overflowed: error */ |
65 | bb_error_msg_and_die("no %cids left", 'g'); |
66 | /* this format string is reused in adduser and addgroup */ |
67 | } |
68 | g->gr_gid++; |
69 | } |
70 | } |
71 | |
72 | /* append a new user to the passwd file */ |
73 | static void new_group(char *group, gid_t gid) |
74 | { |
75 | struct group gr; |
76 | char *p; |
77 | |
78 | /* make sure gid and group haven't already been allocated */ |
79 | gr.gr_gid = gid; |
80 | gr.gr_name = group; |
81 | xgroup_study(&gr); |
82 | |
83 | /* add entry to group */ |
84 | p = xasprintf("x:%u:", (unsigned) gr.gr_gid); |
85 | if (update_passwd(bb_path_group_file, group, p, NULL) < 0) |
86 | exit(EXIT_FAILURE); |
87 | if (ENABLE_FEATURE_CLEAN_UP) |
88 | free(p); |
89 | #if ENABLE_FEATURE_SHADOWPASSWDS |
90 | /* /etc/gshadow fields: |
91 | * 1. Group name. |
92 | * 2. Encrypted password. |
93 | * If set, non-members of the group can join the group |
94 | * by typing the password for that group using the newgrp command. |
95 | * If the value is of this field ! then no user is allowed |
96 | * to access the group using the newgrp command. A value of !! |
97 | * is treated the same as a value of ! only it indicates |
98 | * that a password has never been set before. If the value is null, |
99 | * only group members can log into the group. |
100 | * 3. Group administrators (comma delimited list). |
101 | * Group members listed here can add or remove group members |
102 | * using the gpasswd command. |
103 | * 4. Group members (comma delimited list). |
104 | */ |
105 | /* Ignore errors: if file is missing we assume admin doesn't want it */ |
106 | update_passwd(bb_path_gshadow_file, group, "!::", NULL); |
107 | #endif |
108 | } |
109 | |
110 | #if ENABLE_FEATURE_ADDGROUP_LONG_OPTIONS |
111 | static const char addgroup_longopts[] ALIGN1 = |
112 | "gid\0" Required_argument "g" |
113 | "system\0" No_argument "S" |
114 | ; |
115 | #endif |
116 | |
117 | /* |
118 | * addgroup will take a login_name as its first parameter. |
119 | * |
120 | * gid can be customized via command-line parameters. |
121 | * If called with two non-option arguments, addgroup |
122 | * will add an existing user to an existing group. |
123 | */ |
124 | int addgroup_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
125 | int addgroup_main(int argc UNUSED_PARAM, char **argv) |
126 | { |
127 | unsigned opts; |
128 | unsigned gid = 0; |
129 | |
130 | /* need to be root */ |
131 | if (geteuid()) { |
132 | bb_error_msg_and_die("%s", bb_msg_perm_denied_are_you_root); |
133 | } |
134 | #if ENABLE_FEATURE_ADDGROUP_LONG_OPTIONS |
135 | applet_long_options = addgroup_longopts; |
136 | #endif |
137 | /* Syntax: |
138 | * addgroup group |
139 | * addgroup -g num group |
140 | * addgroup user group |
141 | * Check for min, max and missing args */ |
142 | opt_complementary = "-1:?2:g+"; |
143 | opts = getopt32(argv, "g:S", &gid); |
144 | /* move past the commandline options */ |
145 | argv += optind; |
146 | //argc -= optind; |
147 | |
148 | #if ENABLE_FEATURE_ADDUSER_TO_GROUP |
149 | if (argv[1]) { |
150 | struct group *gr; |
151 | |
152 | if (opts & OPT_GID) { |
153 | /* -g was there, but "addgroup -g num user group" |
154 | * is a no-no */ |
155 | bb_show_usage(); |
156 | } |
157 | |
158 | /* check if group and user exist */ |
159 | xuname2uid(argv[0]); /* unknown user: exit */ |
160 | gr = xgetgrnam(argv[1]); /* unknown group: exit */ |
161 | /* check if user is already in this group */ |
162 | for (; *(gr->gr_mem) != NULL; (gr->gr_mem)++) { |
163 | if (!strcmp(argv[0], *(gr->gr_mem))) { |
164 | /* user is already in group: do nothing */ |
165 | return EXIT_SUCCESS; |
166 | } |
167 | } |
168 | if (update_passwd(bb_path_group_file, argv[1], NULL, argv[0]) < 0) { |
169 | return EXIT_FAILURE; |
170 | } |
171 | # if ENABLE_FEATURE_SHADOWPASSWDS |
172 | update_passwd(bb_path_gshadow_file, argv[1], NULL, argv[0]); |
173 | # endif |
174 | } else |
175 | #endif /* ENABLE_FEATURE_ADDUSER_TO_GROUP */ |
176 | { |
177 | die_if_bad_username(argv[0]); |
178 | new_group(argv[0], gid); |
179 | } |
180 | /* Reached only on success */ |
181 | return EXIT_SUCCESS; |
182 | } |
183 |