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 *
7 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
8 */
9
10/* BB_AUDIT SUSv3 _NOT_ compliant -- option -G is not currently supported. */
11/* Hacked by Tito Ragusa (C) 2004 to handle usernames of whatever length and to
12 * be more similar to GNU id.
13 * -Z option support: by Yuichi Nakamura <ynakam@hitachisoft.jp>
14 */
15
16#include "libbb.h"
17
18#define PRINT_REAL        1
19#define NAME_NOT_NUMBER   2
20#define JUST_USER         4
21#define JUST_GROUP        8
22#if ENABLE_SELINUX
23#define JUST_CONTEXT     16
24#endif
25
26static int printf_full(unsigned int id, const char *arg, const char prefix)
27{
28	const char *fmt = "%cid=%u";
29	int status = EXIT_FAILURE;
30
31	if (arg) {
32		fmt = "%cid=%u(%s)";
33		status = EXIT_SUCCESS;
34	}
35	printf(fmt, prefix, id, arg);
36	return status;
37}
38
39int id_main(int argc, char **argv);
40int id_main(int argc, char **argv)
41{
42	struct passwd *p;
43	uid_t uid;
44	gid_t gid;
45	unsigned long flags;
46	short status;
47#if ENABLE_SELINUX
48	security_context_t scontext;
49#endif
50	/* Don't allow -n -r -nr -ug -rug -nug -rnug */
51	/* Don't allow more than one username */
52	opt_complementary = "?1:u--g:g--u:r?ug:n?ug" USE_SELINUX(":u--Z:Z--u:g--Z:Z--g");
53	flags = getopt32(argv, "rnug" USE_SELINUX("Z"));
54
55	/* This values could be overwritten later */
56	uid = geteuid();
57	gid = getegid();
58	if (flags & PRINT_REAL) {
59		uid = getuid();
60		gid = getgid();
61	}
62
63	if (argv[optind]) {
64		p = getpwnam(argv[optind]);
65		/* xuname2uid is needed because it exits on failure */
66		uid = xuname2uid(argv[optind]);
67		gid = p->pw_gid;
68		/* in this case PRINT_REAL is the same */
69	}
70
71	if (flags & (JUST_GROUP | JUST_USER USE_SELINUX(| JUST_CONTEXT))) {
72		/* JUST_GROUP and JUST_USER are mutually exclusive */
73		if (flags & NAME_NOT_NUMBER) {
74			/* bb_getXXXid(-1) exit on failure, puts cannot segfault */
75			puts((flags & JUST_USER) ? bb_getpwuid(NULL, -1, uid) : bb_getgrgid(NULL, -1, gid));
76		} else {
77			if (flags & JUST_USER) {
78				printf("%u\n", uid);
79			}
80			if (flags & JUST_GROUP) {
81				printf("%u\n", gid);
82			}
83		}
84
85#if ENABLE_SELINUX
86		if (flags & JUST_CONTEXT) {
87			selinux_or_die();
88			if (argc - optind == 1) {
89				bb_error_msg_and_die("user name can't be passed with -Z");
90			}
91
92			if (getcon(&scontext)) {
93				bb_error_msg_and_die("can't get process context");
94			}
95			printf("%s\n", scontext);
96		}
97#endif
98		/* exit */
99		fflush_stdout_and_exit(EXIT_SUCCESS);
100	}
101
102	/* Print full info like GNU id */
103	/* bb_getpwuid(0) doesn't exit on failure (returns NULL) */
104	status = printf_full(uid, bb_getpwuid(NULL, 0, uid), 'u');
105	putchar(' ');
106	status |= printf_full(gid, bb_getgrgid(NULL, 0, gid), 'g');
107
108#if ENABLE_SELINUX
109	if (is_selinux_enabled()) {
110		security_context_t mysid;
111		const char *context;
112
113		context = "unknown";
114		getcon(&mysid);
115		if (mysid) {
116			context = alloca(strlen(mysid) + 1);
117			strcpy((char*)context, mysid);
118			freecon(mysid);
119		}
120		printf(" context=%s", context);
121	}
122#endif
123
124	putchar('\n');
125	fflush_stdout_and_exit(status);
126}
127