path: root/selinux/runcon.c (plain)
blob: 60d41000ccf7ee45d138e3103933af6df73d41a7

1	/*
2	* runcon [ context |
3	* ( [ -c ] [ -r role ] [-t type] [ -u user ] [ -l levelrange ] )
4	* command [arg1 [arg2 ...] ]
5	*
6	* attempt to run the specified command with the specified context.
7	*
8	* -r role : use the current context with the specified role
9	* -t type : use the current context with the specified type
10	* -u user : use the current context with the specified user
11	* -l level : use the current context with the specified level range
12	* -c : compute process transition context before modifying
13	*
14	* Contexts are interpreted as follows:
15	*
16	* Number of MLS
17	* components system?
18	*
19	* 1 - type
20	* 2 - role:type
21	* 3 Y role:type:range
22	* 3 N user:role:type
23	* 4 Y user:role:type:range
24	* 4 N error
25	*
26	* Port to busybox: KaiGai Kohei <kaigai@kaigai.gr.jp>
27	* - based on coreutils-5.97 (in Fedora Core 6)
28	*
29	* Licensed under GPLv2, see file LICENSE in this source tree.
30	*/
31
32	//usage:#define runcon_trivial_usage
33	//usage: "[-c] [-u USER] [-r ROLE] [-t TYPE] [-l RANGE] PROG -- ARGS\n"
34	//usage: "runcon CONTEXT PROG -- ARGS"
35	//usage:#define runcon_full_usage "\n\n"
36	//usage: "Run PROG in a different security context\n"
37	//usage: "\n CONTEXT Complete security context\n"
38	//usage: IF_FEATURE_RUNCON_LONG_OPTIONS(
39	//usage: "\n -c,--compute Compute process transition context before modifying"
40	//usage: "\n -t,--type=TYPE Type (for same role as parent)"
41	//usage: "\n -u,--user=USER User identity"
42	//usage: "\n -r,--role=ROLE Role"
43	//usage: "\n -l,--range=RNG Levelrange"
44	//usage: )
45	//usage: IF_NOT_FEATURE_RUNCON_LONG_OPTIONS(
46	//usage: "\n -c Compute process transition context before modifying"
47	//usage: "\n -t TYPE Type (for same role as parent)"
48	//usage: "\n -u USER User identity"
49	//usage: "\n -r ROLE Role"
50	//usage: "\n -l RNG Levelrange"
51	//usage: )
52
53	#include <selinux/context.h>
54	#ifndef ANDROID
55	#include <selinux/flask.h>
56	#endif
57
58	#include "libbb.h"
59
60	static context_t runcon_compute_new_context(char *user, char *role, char *type, char *range,
61	char *command, int compute_trans)
62	{
63	context_t con;
64	security_context_t cur_context;
65
66	if (getcon(&cur_context))
67	bb_error_msg_and_die("can't get current context");
68
69	if (compute_trans) {
70	security_context_t file_context, new_context;
71
72	if (getfilecon(command, &file_context) < 0)
73	bb_error_msg_and_die("can't retrieve attributes of '%s'",
74	command);
75	if (security_compute_create(cur_context, file_context,
76	SECCLASS_PROCESS, &new_context))
77	bb_error_msg_and_die("unable to compute a new context");
78	cur_context = new_context;
79	}
80
81	con = context_new(cur_context);
82	if (!con)
83	bb_error_msg_and_die("'%s' is not a valid context", cur_context);
84	if (user && context_user_set(con, user))
85	bb_error_msg_and_die("can't set new user '%s'", user);
86	if (type && context_type_set(con, type))
87	bb_error_msg_and_die("can't set new type '%s'", type);
88	if (range && context_range_set(con, range))
89	bb_error_msg_and_die("can't set new range '%s'", range);
90	if (role && context_role_set(con, role))
91	bb_error_msg_and_die("can't set new role '%s'", role);
92
93	return con;
94	}
95
96	#if ENABLE_FEATURE_RUNCON_LONG_OPTIONS
97	static const char runcon_longopts[] ALIGN1 =
98	"user\0" Required_argument "u"
99	"role\0" Required_argument "r"
100	"type\0" Required_argument "t"
101	"range\0" Required_argument "l"
102	"compute\0" No_argument "c"
103	"help\0" No_argument "h"
104	;
105	#endif
106
107	#define OPTS_ROLE (1<<0) /* r */
108	#define OPTS_TYPE (1<<1) /* t */
109	#define OPTS_USER (1<<2) /* u */
110	#define OPTS_RANGE (1<<3) /* l */
111	#define OPTS_COMPUTE (1<<4) /* c */
112	#define OPTS_HELP (1<<5) /* h */
113	#define OPTS_CONTEXT_COMPONENT (OPTS_ROLE | OPTS_TYPE | OPTS_USER | OPTS_RANGE)
114
115	int runcon_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
116	int runcon_main(int argc UNUSED_PARAM, char **argv)
117	{
118	char *role = NULL;
119	char *range = NULL;
120	char *user = NULL;
121	char *type = NULL;
122	char *context = NULL;
123	unsigned opts;
124	context_t con;
125
126	selinux_or_die();
127
128	#if ENABLE_FEATURE_RUNCON_LONG_OPTIONS
129	applet_long_options = runcon_longopts;
130	#endif
131	opt_complementary = "-1";
132	opts = getopt32(argv, "r:t:u:l:ch", &role, &type, &user, &range);
133	argv += optind;
134
135	if (!(opts & OPTS_CONTEXT_COMPONENT)) {
136	context = *argv++;
137	if (!argv[0])
138	bb_error_msg_and_die("no command given");
139	}
140
141	if (context) {
142	con = context_new(context);
143	if (!con)
144	bb_error_msg_and_die("'%s' is not a valid context", context);
145	} else {
146	con = runcon_compute_new_context(user, role, type, range,
147	argv[0], opts & OPTS_COMPUTE);
148	}
149
150	if (security_check_context(context_str(con)))
151	bb_error_msg_and_die("'%s' is not a valid context",
152	context_str(con));
153
154	if (setexeccon(context_str(con)))
155	bb_error_msg_and_die("can't set up security context '%s'",
156	context_str(con));
157
158	BB_EXECVP_or_die(argv);
159	}
160