busybox/loginutils/addgroup.c

/* vi: set sw=4 ts=4: */
/*
 * addgroup - add groups to /etc/group and /etc/gshadow
 *
 * Copyright (C) 1999 by Lineo, inc. and John Beppu
 * Copyright (C) 1999,2000,2001 by John Beppu <beppu@codepoet.org>
 * Copyright (C) 2007 by Tito Ragusa <farmatito@tiscali.it>
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 *
 */
#include "libbb.h"

#if CONFIG_LAST_SYSTEM_ID < CONFIG_FIRST_SYSTEM_ID
#error Bad LAST_SYSTEM_ID or FIRST_SYSTEM_ID in .config
#endif

#define OPT_GID                       (1 << 0)
#define OPT_SYSTEM_ACCOUNT            (1 << 1)

/* We assume GID_T_MAX == INT_MAX */
static void xgroup_study(struct group *g)
{
	unsigned max = INT_MAX;

	/* Make sure gr_name is unused */
	if (getgrnam(g->gr_name)) {
		bb_error_msg_and_die("%s '%s' in use", "group", g->gr_name);
		/* these format strings are reused in adduser and addgroup */
	}

	/* if a specific gid is requested, the --system switch and */
	/* min and max values are overridden, and the range of valid */
	/* gid values is set to [0, INT_MAX] */
	if (!(option_mask32 & OPT_GID)) {
		if (option_mask32 & OPT_SYSTEM_ACCOUNT) {
			g->gr_gid = CONFIG_FIRST_SYSTEM_ID;
			max = CONFIG_LAST_SYSTEM_ID;
		} else {
			g->gr_gid = CONFIG_LAST_SYSTEM_ID + 1;
			max = 64999;
		}
	}
	/* Check if the desired gid is free
	 * or find the first free one */
	while (1) {
		if (!getgrgid(g->gr_gid)) {
			return; /* found free group: return */
		}
		if (option_mask32 & OPT_GID) {
			/* -g N, cannot pick gid other than N: error */
			bb_error_msg_and_die("%s '%s' in use", "gid", itoa(g->gr_gid));
			/* this format strings is reused in adduser and addgroup */
		}
		if (g->gr_gid == max) {
			/* overflowed: error */
			bb_error_msg_and_die("no %cids left", 'g');
			/* this format string is reused in adduser and addgroup */
		}
		g->gr_gid++;
	}
}

/* append a new user to the passwd file */
static void new_group(char *group, gid_t gid)
{
	struct group gr;
	char *p;

	/* make sure gid and group haven't already been allocated */
	gr.gr_gid = gid;
	gr.gr_name = group;
	xgroup_study(&gr);

	/* add entry to group */
	p = xasprintf("x:%u:", (unsigned) gr.gr_gid);
	if (update_passwd(bb_path_group_file, group, p, NULL) < 0)
		exit(EXIT_FAILURE);
	if (ENABLE_FEATURE_CLEAN_UP)
		free(p);
#if ENABLE_FEATURE_SHADOWPASSWDS
	/* /etc/gshadow fields:
	 * 1. Group name.
	 * 2. Encrypted password.
	 *    If set, non-members of the group can join the group
	 *    by typing the password for that group using the newgrp command.
	 *    If the value is of this field ! then no user is allowed
	 *    to access the group using the newgrp command. A value of !!
	 *    is treated the same as a value of ! only it indicates
	 *    that a password has never been set before. If the value is null,
	 *    only group members can log into the group.
	 * 3. Group administrators (comma delimited list).
	 *    Group members listed here can add or remove group members
	 *    using the gpasswd command.
	 * 4. Group members (comma delimited list).
	 */
	/* Ignore errors: if file is missing we assume admin doesn't want it */
	update_passwd(bb_path_gshadow_file, group, "!::", NULL);
#endif
}

#if ENABLE_FEATURE_ADDGROUP_LONG_OPTIONS
static const char addgroup_longopts[] ALIGN1 =
		"gid\0"                 Required_argument "g"
		"system\0"              No_argument       "S"
		;
#endif

/*
 * addgroup will take a login_name as its first parameter.
 *
 * gid can be customized via command-line parameters.
 * If called with two non-option arguments, addgroup
 * will add an existing user to an existing group.
 */
int addgroup_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int addgroup_main(int argc UNUSED_PARAM, char **argv)
{
	unsigned opts;
	unsigned gid = 0;

	/* need to be root */
	if (geteuid()) {
		bb_error_msg_and_die(bb_msg_perm_denied_are_you_root);
	}
#if ENABLE_FEATURE_ADDGROUP_LONG_OPTIONS
	applet_long_options = addgroup_longopts;
#endif
	/* Syntax:
	 *  addgroup group
	 *  addgroup -g num group
	 *  addgroup user group
	 * Check for min, max and missing args */
	opt_complementary = "-1:?2:g+";
	opts = getopt32(argv, "g:S", &gid);
	/* move past the commandline options */
	argv += optind;
	//argc -= optind;

#if ENABLE_FEATURE_ADDUSER_TO_GROUP
	if (argv[1]) {
		struct group *gr;

		if (opts & OPT_GID) {
			/* -g was there, but "addgroup -g num user group"
			 * is a no-no */
			bb_show_usage();
		}

		/* check if group and user exist */
		xuname2uid(argv[0]); /* unknown user: exit */
		gr = xgetgrnam(argv[1]); /* unknown group: exit */
		/* check if user is already in this group */
		for (; *(gr->gr_mem) != NULL; (gr->gr_mem)++) {
			if (!strcmp(argv[0], *(gr->gr_mem))) {
				/* user is already in group: do nothing */
				return EXIT_SUCCESS;
			}
		}
		if (update_passwd(bb_path_group_file, argv[1], NULL, argv[0]) < 0) {
			return EXIT_FAILURE;
		}
# if ENABLE_FEATURE_SHADOWPASSWDS
		update_passwd(bb_path_gshadow_file, argv[1], NULL, argv[0]);
# endif
	} else
#endif /* ENABLE_FEATURE_ADDUSER_TO_GROUP */
	{
		die_if_bad_username(argv[0]);
		new_group(argv[0], gid);

	}
	/* Reached only on success */
	return EXIT_SUCCESS;
}
1	niro	532	/* vi: set sw=4 ts=4: */
2			/*
3	niro	816	* addgroup - add groups to /etc/group and /etc/gshadow
4	niro	532	*
5			* Copyright (C) 1999 by Lineo, inc. and John Beppu
6			* Copyright (C) 1999,2000,2001 by John Beppu <beppu@codepoet.org>
7	niro	816	* Copyright (C) 2007 by Tito Ragusa <farmatito@tiscali.it>
8	niro	532	*
9			* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
10			*
11			*/
12	niro	816	#include "libbb.h"
13	niro	532
14	niro	984	#if CONFIG_LAST_SYSTEM_ID < CONFIG_FIRST_SYSTEM_ID
15			#error Bad LAST_SYSTEM_ID or FIRST_SYSTEM_ID in .config
16			#endif
17
18			#define OPT_GID (1 << 0)
19			#define OPT_SYSTEM_ACCOUNT (1 << 1)
20
21			/* We assume GID_T_MAX == INT_MAX */
22	niro	816	static void xgroup_study(struct group *g)
23	niro	532	{
24	niro	984	unsigned max = INT_MAX;
25
26	niro	816	/* Make sure gr_name is unused */
27			if (getgrnam(g->gr_name)) {
28	niro	984	bb_error_msg_and_die("%s '%s' in use", "group", g->gr_name);
29			/* these format strings are reused in adduser and addgroup */
30	niro	816	}
31	niro	532
32	niro	984	/* if a specific gid is requested, the --system switch and */
33			/* min and max values are overridden, and the range of valid */
34			/* gid values is set to [0, INT_MAX] */
35			if (!(option_mask32 & OPT_GID)) {
36			if (option_mask32 & OPT_SYSTEM_ACCOUNT) {
37			g->gr_gid = CONFIG_FIRST_SYSTEM_ID;
38			max = CONFIG_LAST_SYSTEM_ID;
39			} else {
40			g->gr_gid = CONFIG_LAST_SYSTEM_ID + 1;
41			max = 64999;
42			}
43			}
44	niro	816	/* Check if the desired gid is free
45			* or find the first free one */
46			while (1) {
47			if (!getgrgid(g->gr_gid)) {
48			return; /* found free group: return */
49	niro	532	}
50	niro	984	if (option_mask32 & OPT_GID) {
51	niro	816	/* -g N, cannot pick gid other than N: error */
52	niro	984	bb_error_msg_and_die("%s '%s' in use", "gid", itoa(g->gr_gid));
53			/* this format strings is reused in adduser and addgroup */
54	niro	532	}
55	niro	984	if (g->gr_gid == max) {
56	niro	816	/* overflowed: error */
57	niro	984	bb_error_msg_and_die("no %cids left", 'g');
58			/* this format string is reused in adduser and addgroup */
59	niro	532	}
60	niro	984	g->gr_gid++;
61	niro	532	}
62			}
63
64			/* append a new user to the passwd file */
65	niro	816	static void new_group(char *group, gid_t gid)
66	niro	532	{
67			struct group gr;
68	niro	984	char *p;
69	niro	532
70			/* make sure gid and group haven't already been allocated */
71			gr.gr_gid = gid;
72			gr.gr_name = group;
73	niro	816	xgroup_study(&gr);
74	niro	532
75			/* add entry to group */
76	niro	984	p = xasprintf("x:%u:", (unsigned) gr.gr_gid);
77			if (update_passwd(bb_path_group_file, group, p, NULL) < 0)
78			exit(EXIT_FAILURE);
79	niro	816	if (ENABLE_FEATURE_CLEAN_UP)
80	niro	984	free(p);
81	niro	532	#if ENABLE_FEATURE_SHADOWPASSWDS
82	niro	984	/* /etc/gshadow fields:
83			* 1. Group name.
84			* 2. Encrypted password.
85			* If set, non-members of the group can join the group
86			* by typing the password for that group using the newgrp command.
87			* If the value is of this field ! then no user is allowed
88			* to access the group using the newgrp command. A value of !!
89			* is treated the same as a value of ! only it indicates
90			* that a password has never been set before. If the value is null,
91			* only group members can log into the group.
92			* 3. Group administrators (comma delimited list).
93			* Group members listed here can add or remove group members
94			* using the gpasswd command.
95			* 4. Group members (comma delimited list).
96			*/
97			/* Ignore errors: if file is missing we assume admin doesn't want it */
98			update_passwd(bb_path_gshadow_file, group, "!::", NULL);
99	niro	532	#endif
100	niro	816	}
101	niro	532
102	niro	984	#if ENABLE_FEATURE_ADDGROUP_LONG_OPTIONS
103			static const char addgroup_longopts[] ALIGN1 =
104			"gid\0" Required_argument "g"
105			"system\0" No_argument "S"
106			;
107	niro	816	#endif
108	niro	532
109			/*
110			* addgroup will take a login_name as its first parameter.
111			*
112	niro	816	* gid can be customized via command-line parameters.
113			* If called with two non-option arguments, addgroup
114			* will add an existing user to an existing group.
115			*/
116			int addgroup_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
117			int addgroup_main(int argc UNUSED_PARAM, char **argv)
118	niro	532	{
119	niro	984	unsigned opts;
120			unsigned gid = 0;
121	niro	532
122	niro	816	/* need to be root */
123			if (geteuid()) {
124			bb_error_msg_and_die(bb_msg_perm_denied_are_you_root);
125	niro	532	}
126	niro	984	#if ENABLE_FEATURE_ADDGROUP_LONG_OPTIONS
127			applet_long_options = addgroup_longopts;
128			#endif
129	niro	816	/* Syntax:
130			* addgroup group
131			* addgroup -g num group
132			* addgroup user group
133			* Check for min, max and missing args */
134	niro	984	opt_complementary = "-1:?2:g+";
135			opts = getopt32(argv, "g:S", &gid);
136	niro	532	/* move past the commandline options */
137			argv += optind;
138	niro	816	//argc -= optind;
139	niro	532
140	niro	816	#if ENABLE_FEATURE_ADDUSER_TO_GROUP
141			if (argv[1]) {
142			struct group *gr;
143
144	niro	984	if (opts & OPT_GID) {
145	niro	816	/* -g was there, but "addgroup -g num user group"
146			* is a no-no */
147			bb_show_usage();
148			}
149
150			/* check if group and user exist */
151			xuname2uid(argv[0]); /* unknown user: exit */
152	niro	984	gr = xgetgrnam(argv[1]); /* unknown group: exit */
153	niro	816	/* check if user is already in this group */
154			for (; *(gr->gr_mem) != NULL; (gr->gr_mem)++) {
155			if (!strcmp(argv[0], *(gr->gr_mem))) {
156			/* user is already in group: do nothing */
157			return EXIT_SUCCESS;
158			}
159			}
160	niro	984	if (update_passwd(bb_path_group_file, argv[1], NULL, argv[0]) < 0) {
161			return EXIT_FAILURE;
162			}
163			# if ENABLE_FEATURE_SHADOWPASSWDS
164			update_passwd(bb_path_gshadow_file, argv[1], NULL, argv[0]);
165			# endif
166	niro	816	} else
167			#endif /* ENABLE_FEATURE_ADDUSER_TO_GROUP */
168			{
169			die_if_bad_username(argv[0]);
170			new_group(argv[0], gid);
171
172	niro	532	}
173	niro	816	/* Reached only on success */
174			return EXIT_SUCCESS;
175	niro	532	}