summaryrefslogtreecommitdiff
path: root/selinux/chcon.c
blob: 9b13679b87702a77c407ee512a430f7afce7b9e7 (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
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
/*
 * chcon -- change security context, based on coreutils-5.97-13
 *
 * Port to busybox: KaiGai Kohei <kaigai@kaigai.gr.jp>
 *
 * Copyright (C) 2006 - 2007 KaiGai Kohei <kaigai@kaigai.gr.jp>
 *
 * Licensed under GPLv2, see file LICENSE in this source tree.
 */
//config:config CHCON
//config:	bool "chcon (8.9 kb)"
//config:	default n
//config:	depends on SELINUX
//config:	help
//config:	Enable support to change the security context of file.

//applet:IF_CHCON(APPLET(chcon, BB_DIR_USR_BIN, BB_SUID_DROP))

//kbuild:lib-$(CONFIG_CHCON) += chcon.o

//usage:#define chcon_trivial_usage
//usage:       "[OPTIONS] CONTEXT FILE..."
//usage:       "\n	chcon [OPTIONS] [-u USER] [-r ROLE] [-l RANGE] [-t TYPE] FILE..."
//usage:	IF_LONG_OPTS(
//usage:       "\n	chcon [OPTIONS] --reference=RFILE FILE..."
//usage:	)
//usage:
//usage:#define chcon_full_usage "\n\n"
//usage:       "Change the security context of each FILE to CONTEXT\n"
//usage:     "\n	-v	Verbose"
//usage:     "\n	-c	Report changes made"
//usage:     "\n	-h	Affect symlinks instead of their targets"
//usage:     "\n	-f	Suppress most error messages"
//usage:	IF_LONG_OPTS(
//usage:     "\n	--reference RFILE Use RFILE's group instead of using a CONTEXT value"
//usage:	)
//usage:     "\n	-u USER	Set user/role/type/range in the target security context"
//usage:     "\n	-r ROLE"
//usage:     "\n	-t TYPE"
//usage:     "\n	-l RNG"
//usage:     "\n	-R	Recurse"

#include <selinux/context.h>

#include "libbb.h"

#define OPT_RECURSIVE		(1<<0)	/* 'R' */
#define OPT_CHANHES		(1<<1)	/* 'c' */
#define OPT_NODEREFERENCE	(1<<2)	/* 'h' */
#define OPT_QUIET		(1<<3)	/* 'f' */
#define OPT_USER		(1<<4)	/* 'u' */
#define OPT_ROLE		(1<<5)	/* 'r' */
#define OPT_TYPE		(1<<6)	/* 't' */
#define OPT_RANGE		(1<<7)	/* 'l' */
#define OPT_VERBOSE		(1<<8)	/* 'v' */
#define OPT_REFERENCE		((1<<9) * ENABLE_LONG_OPTS)
#define OPT_COMPONENT_SPECIFIED	(OPT_USER | OPT_ROLE | OPT_TYPE | OPT_RANGE)

static char *user = NULL;
static char *role = NULL;
static char *type = NULL;
static char *range = NULL;
static char *specified_context = NULL;

static int FAST_FUNC change_filedir_context(struct recursive_state *state UNUSED_PARAM,
		const char *fname,
		struct stat *stbuf UNUSED_PARAM)
{
	context_t context = NULL;
	security_context_t file_context = NULL;
	security_context_t context_string;
	int rc = FALSE;
	int status = 0;

	if (option_mask32 & OPT_NODEREFERENCE) {
		status = lgetfilecon(fname, &file_context);
	} else {
		status = getfilecon(fname, &file_context);
	}
	if (status < 0 && errno != ENODATA) {
		if ((option_mask32 & OPT_QUIET) == 0)
			bb_error_msg("can't obtain security context: %s", fname);
		goto skip;
	}

	if (file_context == NULL && specified_context == NULL) {
		bb_error_msg("can't apply partial context to unlabeled file %s", fname);
		goto skip;
	}

	if (specified_context == NULL) {
		context = set_security_context_component(file_context,
							user, role, type, range);
		if (!context) {
			bb_error_msg("can't compute security context from %s", file_context);
			goto skip;
		}
	} else {
		context = context_new(specified_context);
		if (!context) {
			bb_error_msg("invalid context: %s", specified_context);
			goto skip;
		}
	}

	context_string = context_str(context);
	if (!context_string) {
		bb_simple_error_msg("can't obtain security context in text expression");
		goto skip;
	}

	if (file_context == NULL || strcmp(context_string, file_context) != 0) {
		int fail;

		if (option_mask32 & OPT_NODEREFERENCE) {
			fail = lsetfilecon(fname, context_string);
		} else {
			fail = setfilecon(fname, context_string);
		}
		if ((option_mask32 & OPT_VERBOSE) || ((option_mask32 & OPT_CHANHES) && !fail)) {
			printf(!fail
				? "context of %s changed to %s\n"
				: "can't change context of %s to %s\n",
				fname, context_string);
		}
		if (!fail) {
			rc = TRUE;
		} else if ((option_mask32 & OPT_QUIET) == 0) {
			bb_error_msg("can't change context of %s to %s",
					fname, context_string);
		}
	} else {
		if (option_mask32 & OPT_VERBOSE) {
			printf("context of %s retained as %s\n", fname, context_string);
		}
		rc = TRUE;
	}
skip:
	context_free(context);
	freecon(file_context);

	return rc;
}

#if ENABLE_LONG_OPTS
static const char chcon_longopts[] ALIGN1 =
	"recursive\0"      No_argument       "R"
	"changes\0"        No_argument       "c"
	"no-dereference\0" No_argument       "h"
	"silent\0"         No_argument       "f"
	"quiet\0"          No_argument       "f"
	"user\0"           Required_argument "u"
	"role\0"           Required_argument "r"
	"type\0"           Required_argument "t"
	"range\0"          Required_argument "l"
	"verbose\0"        No_argument       "v"
	"reference\0"      Required_argument "\xff" /* no short option */
	;
#endif

int chcon_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int chcon_main(int argc UNUSED_PARAM, char **argv)
{
	char *reference_file;
	char *fname;
	int i, errors = 0;

	getopt32long(argv, "^"
		"Rchfu:r:t:l:v"
		"\0"
		"-1" /* at least 1 arg */
		":?" /* error if exclusivity constraints are violated */
#if ENABLE_LONG_OPTS
		":\xff--urtl:u--\xff:r--\xff:t--\xff:l--\xff"
#endif
		":f--v:v--f"  /* 'verbose' and 'quiet' are exclusive */
		, chcon_longopts,
		&user, &role, &type, &range, &reference_file
	);
	argv += optind;

#if ENABLE_LONG_OPTS
	if (option_mask32 & OPT_REFERENCE) {
		/* FIXME: lgetfilecon() should be used when '-h' is specified.
		 * But current implementation follows the original one. */
		if (getfilecon(reference_file, &specified_context) < 0)
			bb_perror_msg_and_die("getfilecon('%s') failed", reference_file);
	} else
#endif
	if ((option_mask32 & OPT_COMPONENT_SPECIFIED) == 0) {
		specified_context = *argv++;
		/* specified_context is never NULL -
		 * "-1" in opt_complementary prevents this. */
		if (!argv[0])
			bb_simple_error_msg_and_die("too few arguments");
	}

	for (i = 0; (fname = argv[i]) != NULL; i++) {
		int fname_len = strlen(fname);
		while (fname_len > 1 && fname[fname_len - 1] == '/')
			fname_len--;
		fname[fname_len] = '\0';

		if (recursive_action(fname,
					((option_mask32 & OPT_RECURSIVE) ? ACTION_RECURSE : 0),
					change_filedir_context,
					change_filedir_context,
					NULL) != TRUE)
			errors = 1;
	}
	return errors;
}