busybox/coreutils/id.c

/* vi: set sw=4 ts=4: */
/*
 * Mini id implementation for busybox
 *
 * Copyright (C) 2000 by Randolph Chung <tausq@debian.org>
 * Copyright (C) 2008 by Tito Ragusa <farmatito@tiscali.it>
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 */

/* BB_AUDIT SUSv3 compliant. */
/* Hacked by Tito Ragusa (C) 2004 to handle usernames of whatever
 * length and to be more similar to GNU id.
 * -Z option support: by Yuichi Nakamura <ynakam@hitachisoft.jp>
 * Added -G option Tito Ragusa (C) 2008 for SUSv3.
 */

#include "libbb.h"

#if !ENABLE_USE_BB_PWD_GRP
#if defined(__UCLIBC_MAJOR__) && (__UCLIBC_MAJOR__ == 0)
#if (__UCLIBC_MINOR__ < 9) || (__UCLIBC_MINOR__ == 9 &&  __UCLIBC_SUBLEVEL__ < 30)
#error "Sorry, you need at least uClibc version 0.9.30 for id applet to build"
#endif
#endif
#endif

enum {
	PRINT_REAL      = (1 << 0),
	NAME_NOT_NUMBER = (1 << 1),
	JUST_USER       = (1 << 2),
	JUST_GROUP      = (1 << 3),
	JUST_ALL_GROUPS = (1 << 4),
#if ENABLE_SELINUX
	JUST_CONTEXT    = (1 << 5),
#endif
};

static int print_common(unsigned id,
		char* FAST_FUNC bb_getXXXid(char *name, int bufsize, long uid),
		const char *prefix)
{
	const char *name = bb_getXXXid(NULL, 0, id);

	if (prefix) {
		printf("%s", prefix);
	}
	if (!(option_mask32 & NAME_NOT_NUMBER) || !name) {
		printf("%u", id);
	}
	if (!option_mask32 || (option_mask32 & NAME_NOT_NUMBER)) {
		if (name) {
			printf(option_mask32 ? "%s" : "(%s)", name);
		} else {
			/* Don't set error status flag in default mode */
			if (option_mask32) {
				if (ENABLE_DESKTOP)
					bb_error_msg("unknown ID %u", id);
				return EXIT_FAILURE;
			}
		}
	}
	return EXIT_SUCCESS;
}

static int print_group(gid_t id, const char *prefix)
{
	return print_common(id, bb_getgrgid, prefix);
}

static int print_user(uid_t id, const char *prefix)
{
	return print_common(id, bb_getpwuid, prefix);
}

/* On error set *n < 0 and return >= 0
 * If *n is too small, update it and return < 0
 *  (ok to trash groups[] in both cases)
 * Otherwise fill in groups[] and return >= 0
 */
static int get_groups(const char *username, gid_t rgid, gid_t *groups, int *n)
{
	int m;

	if (username) {
		/* If the user is a member of more than
		 * *n groups, then -1 is returned. Otherwise >= 0.
		 * (and no defined way of detecting errors?!) */
		m = getgrouplist(username, rgid, groups, n);
		/* I guess *n < 0 might indicate error. Anyway,
		 * malloc'ing -1 bytes won't be good, so: */
		//if (*n < 0)
		//	return 0;
		//return m;
		//commented out here, happens below anyway
	} else {
		/* On error -1 is returned, which ends up in *n */
		int nn = getgroups(*n, groups);
		/* 0: nn <= *n, groups[] was big enough; -1 otherwise */
		m = - (nn > *n);
		*n = nn;
	}
	if (*n < 0)
		return 0; /* error, don't return < 0! */
	return m;
}

int id_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int id_main(int argc UNUSED_PARAM, char **argv)
{
	uid_t ruid;
	gid_t rgid;
	uid_t euid;
	gid_t egid;
	unsigned opt;
	int i;
	int status = EXIT_SUCCESS;
	const char *prefix;
	const char *username;
#if ENABLE_SELINUX
	security_context_t scontext = NULL;
#endif
	/* Don't allow -n -r -nr -ug -rug -nug -rnug -uZ -gZ -GZ*/
	/* Don't allow more than one username */
	opt_complementary = "?1:u--g:g--u:G--u:u--G:g--G:G--g:r?ugG:n?ugG"
			 USE_SELINUX(":u--Z:Z--u:g--Z:Z--g:G--Z:Z--G");
	opt = getopt32(argv, "rnugG" USE_SELINUX("Z"));

	username = argv[optind];
	if (username) {
		struct passwd *p = getpwnam(username);
		if (!p)
			bb_error_msg_and_die("unknown user %s", username);
		euid = ruid = p->pw_uid;
		egid = rgid = p->pw_gid;
	} else {
		egid = getegid();
		rgid = getgid();
		euid = geteuid();
		ruid = getuid();
	}
	/* JUST_ALL_GROUPS ignores -r PRINT_REAL flag even if man page for */
	/* id says: print the real ID instead of the effective ID, with -ugG */
	/* in fact in this case egid is always printed if egid != rgid */
	if (!opt || (opt & JUST_ALL_GROUPS)) {
		gid_t *groups;
		int n;

		if (!opt) {
			/* Default Mode */
			status |= print_user(ruid, "uid=");
			status |= print_group(rgid, " gid=");
			if (euid != ruid)
				status |= print_user(euid, " euid=");
			if (egid != rgid)
				status |= print_group(egid, " egid=");
		} else {
			/* JUST_ALL_GROUPS */
			status |= print_group(rgid, NULL);
			if (egid != rgid)
				status |= print_group(egid, " ");
		}
		/* We are supplying largish buffer, trying
		 * to not run get_groups() twice. That might be slow
		 * ("user database in remote SQL server" case) */
		groups = xmalloc(64 * sizeof(gid_t));
		n = 64;
		if (get_groups(username, rgid, groups, &n) < 0) {
			/* Need bigger buffer after all */
			groups = xrealloc(groups, n * sizeof(gid_t));
			get_groups(username, rgid, groups, &n);
		}
		if (n > 0) {
			/* Print the list */
			prefix = " groups=";
			for (i = 0; i < n; i++) {
				if (opt && (groups[i] == rgid || groups[i] == egid))
					continue;
				status |= print_group(groups[i], opt ? " " : prefix);
				prefix = ",";
			}
		} else if (n < 0) { /* error in get_groups() */
			if (!ENABLE_DESKTOP)
				bb_error_msg_and_die("cannot get groups");
			else
				return EXIT_FAILURE;
		}
		if (ENABLE_FEATURE_CLEAN_UP)
			free(groups);
#if ENABLE_SELINUX
		if (is_selinux_enabled()) {
			if (getcon(&scontext) == 0)
				printf(" context=%s", scontext);
		}
#endif
	} else if (opt & PRINT_REAL) {
		euid = ruid;
		egid = rgid;
	}

	if (opt & JUST_USER)
		status |= print_user(euid, NULL);
	else if (opt & JUST_GROUP)
		status |= print_group(egid, NULL);
#if ENABLE_SELINUX
	else if (opt & JUST_CONTEXT) {
		selinux_or_die();
		if (username || getcon(&scontext)) {
			bb_error_msg_and_die("can't get process context%s",
				username ? " for a different user" : "");
		}
		fputs(scontext, stdout);
	}
	/* freecon(NULL) seems to be harmless */
	if (ENABLE_FEATURE_CLEAN_UP)
		freecon(scontext);
#endif
	bb_putchar('\n');
	fflush_stdout_and_exit(status);
}
1	/* vi: set sw=4 ts=4: */
2	/*
3	* Mini id implementation for busybox
4	*
5	* Copyright (C) 2000 by Randolph Chung <tausq@debian.org>
6	* Copyright (C) 2008 by Tito Ragusa <farmatito@tiscali.it>
7	*
8	* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
9	*/
10
11	/* BB_AUDIT SUSv3 compliant. */
12	/* Hacked by Tito Ragusa (C) 2004 to handle usernames of whatever
13	* length and to be more similar to GNU id.
14	* -Z option support: by Yuichi Nakamura <ynakam@hitachisoft.jp>
15	* Added -G option Tito Ragusa (C) 2008 for SUSv3.
16	*/
17
18	#include "libbb.h"
19
20	#if !ENABLE_USE_BB_PWD_GRP
21	#if defined(__UCLIBC_MAJOR__) && (__UCLIBC_MAJOR__ == 0)
22	#if (__UCLIBC_MINOR__ < 9) \|\| (__UCLIBC_MINOR__ == 9 && __UCLIBC_SUBLEVEL__ < 30)
23	#error "Sorry, you need at least uClibc version 0.9.30 for id applet to build"
24	#endif
25	#endif
26	#endif
27
28	enum {
29	PRINT_REAL = (1 << 0),
30	NAME_NOT_NUMBER = (1 << 1),
31	JUST_USER = (1 << 2),
32	JUST_GROUP = (1 << 3),
33	JUST_ALL_GROUPS = (1 << 4),
34	#if ENABLE_SELINUX
35	JUST_CONTEXT = (1 << 5),
36	#endif
37	};
38
39	static int print_common(unsigned id,
40	char* FAST_FUNC bb_getXXXid(char *name, int bufsize, long uid),
41	const char *prefix)
42	{
43	const char *name = bb_getXXXid(NULL, 0, id);
44
45	if (prefix) {
46	printf("%s", prefix);
47	}
48	if (!(option_mask32 & NAME_NOT_NUMBER) \|\| !name) {
49	printf("%u", id);
50	}
51	if (!option_mask32 \|\| (option_mask32 & NAME_NOT_NUMBER)) {
52	if (name) {
53	printf(option_mask32 ? "%s" : "(%s)", name);
54	} else {
55	/* Don't set error status flag in default mode */
56	if (option_mask32) {
57	if (ENABLE_DESKTOP)
58	bb_error_msg("unknown ID %u", id);
59	return EXIT_FAILURE;
60	}
61	}
62	}
63	return EXIT_SUCCESS;
64	}
65
66	static int print_group(gid_t id, const char *prefix)
67	{
68	return print_common(id, bb_getgrgid, prefix);
69	}
70
71	static int print_user(uid_t id, const char *prefix)
72	{
73	return print_common(id, bb_getpwuid, prefix);
74	}
75
76	/* On error set *n < 0 and return >= 0
77	* If *n is too small, update it and return < 0
78	* (ok to trash groups[] in both cases)
79	* Otherwise fill in groups[] and return >= 0
80	*/
81	static int get_groups(const char username, gid_t rgid, gid_t groups, int *n)
82	{
83	int m;
84
85	if (username) {
86	/* If the user is a member of more than
87	* *n groups, then -1 is returned. Otherwise >= 0.
88	* (and no defined way of detecting errors?!) */
89	m = getgrouplist(username, rgid, groups, n);
90	/* I guess *n < 0 might indicate error. Anyway,
91	* malloc'ing -1 bytes won't be good, so: */
92	//if (*n < 0)
93	// return 0;
94	//return m;
95	//commented out here, happens below anyway
96	} else {
97	/* On error -1 is returned, which ends up in n /
98	int nn = getgroups(*n, groups);
99	/* 0: nn <= n, groups[] was big enough; -1 otherwise /
100	m = - (nn > *n);
101	*n = nn;
102	}
103	if (*n < 0)
104	return 0; /* error, don't return < 0! */
105	return m;
106	}
107
108	int id_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
109	int id_main(int argc UNUSED_PARAM, char **argv)
110	{
111	uid_t ruid;
112	gid_t rgid;
113	uid_t euid;
114	gid_t egid;
115	unsigned opt;
116	int i;
117	int status = EXIT_SUCCESS;
118	const char *prefix;
119	const char *username;
120	#if ENABLE_SELINUX
121	security_context_t scontext = NULL;
122	#endif
123	/* Don't allow -n -r -nr -ug -rug -nug -rnug -uZ -gZ -GZ*/
124	/* Don't allow more than one username */
125	opt_complementary = "?1:u--g:g--u:G--u:u--G:g--G:G--g:r?ugG:n?ugG"
126	USE_SELINUX(":u--Z:Z--u:g--Z:Z--g:G--Z:Z--G");
127	opt = getopt32(argv, "rnugG" USE_SELINUX("Z"));
128
129	username = argv[optind];
130	if (username) {
131	struct passwd *p = getpwnam(username);
132	if (!p)
133	bb_error_msg_and_die("unknown user %s", username);
134	euid = ruid = p->pw_uid;
135	egid = rgid = p->pw_gid;
136	} else {
137	egid = getegid();
138	rgid = getgid();
139	euid = geteuid();
140	ruid = getuid();
141	}
142	/* JUST_ALL_GROUPS ignores -r PRINT_REAL flag even if man page for */
143	/* id says: print the real ID instead of the effective ID, with -ugG */
144	/* in fact in this case egid is always printed if egid != rgid */
145	if (!opt \|\| (opt & JUST_ALL_GROUPS)) {
146	gid_t *groups;
147	int n;
148
149	if (!opt) {
150	/* Default Mode */
151	status \|= print_user(ruid, "uid=");
152	status \|= print_group(rgid, " gid=");
153	if (euid != ruid)
154	status \|= print_user(euid, " euid=");
155	if (egid != rgid)
156	status \|= print_group(egid, " egid=");
157	} else {
158	/* JUST_ALL_GROUPS */
159	status \|= print_group(rgid, NULL);
160	if (egid != rgid)
161	status \|= print_group(egid, " ");
162	}
163	/* We are supplying largish buffer, trying
164	* to not run get_groups() twice. That might be slow
165	* ("user database in remote SQL server" case) */
166	groups = xmalloc(64 * sizeof(gid_t));
167	n = 64;
168	if (get_groups(username, rgid, groups, &n) < 0) {
169	/* Need bigger buffer after all */
170	groups = xrealloc(groups, n * sizeof(gid_t));
171	get_groups(username, rgid, groups, &n);
172	}
173	if (n > 0) {
174	/* Print the list */
175	prefix = " groups=";
176	for (i = 0; i < n; i++) {
177	if (opt && (groups[i] == rgid \|\| groups[i] == egid))
178	continue;
179	status \|= print_group(groups[i], opt ? " " : prefix);
180	prefix = ",";
181	}
182	} else if (n < 0) { /* error in get_groups() */
183	if (!ENABLE_DESKTOP)
184	bb_error_msg_and_die("cannot get groups");
185	else
186	return EXIT_FAILURE;
187	}
188	if (ENABLE_FEATURE_CLEAN_UP)
189	free(groups);
190	#if ENABLE_SELINUX
191	if (is_selinux_enabled()) {
192	if (getcon(&scontext) == 0)
193	printf(" context=%s", scontext);
194	}
195	#endif
196	} else if (opt & PRINT_REAL) {
197	euid = ruid;
198	egid = rgid;
199	}
200
201	if (opt & JUST_USER)
202	status \|= print_user(euid, NULL);
203	else if (opt & JUST_GROUP)
204	status \|= print_group(egid, NULL);
205	#if ENABLE_SELINUX
206	else if (opt & JUST_CONTEXT) {
207	selinux_or_die();
208	if (username \|\| getcon(&scontext)) {
209	bb_error_msg_and_die("can't get process context%s",
210	username ? " for a different user" : "");
211	}
212	fputs(scontext, stdout);
213	}
214	/* freecon(NULL) seems to be harmless */
215	if (ENABLE_FEATURE_CLEAN_UP)
216	freecon(scontext);
217	#endif
218	bb_putchar('\n');
219	fflush_stdout_and_exit(status);
220	}