summaryrefslogtreecommitdiff
path: root/scripts/selinux/mdp/mdp.c
blob: 576d11a60417b4f9ae68293bc696c7173e5e2118 (plain) (blame)
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
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *
 * mdp - make dummy policy
 *
 * When pointed at a kernel tree, builds a dummy policy for that kernel
 * with exactly one type with full rights to itself.
 *
 * Copyright (C) IBM Corporation, 2006
 *
 * Authors: Serge E. Hallyn <serue@us.ibm.com>
 */


/* NOTE: we really do want to use the kernel headers here */
#define __EXPORTED_HEADERS__

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <linux/kconfig.h>

static void usage(char *name)
{
	printf("usage: %s [-m] policy_file context_file\n", name);
	exit(1);
}

/* Class/perm mapping support */
struct security_class_mapping {
	const char *name;
	const char *perms[sizeof(unsigned) * 8 + 1];
};

#include "classmap.h"
#include "initial_sid_to_string.h"

int main(int argc, char *argv[])
{
	int i, j, mls = 0;
	int initial_sid_to_string_len;
	char **arg, *polout, *ctxout;

	FILE *fout;

	if (argc < 3)
		usage(argv[0]);
	arg = argv+1;
	if (argc==4 && strcmp(argv[1], "-m") == 0) {
		mls = 1;
		arg++;
	}
	polout = *arg++;
	ctxout = *arg;

	fout = fopen(polout, "w");
	if (!fout) {
		printf("Could not open %s for writing\n", polout);
		usage(argv[0]);
	}

	/* print out the classes */
	for (i = 0; secclass_map[i].name; i++)
		fprintf(fout, "class %s\n", secclass_map[i].name);
	fprintf(fout, "\n");

	initial_sid_to_string_len = sizeof(initial_sid_to_string) / sizeof (char *);
	/* print out the sids */
	for (i = 1; i < initial_sid_to_string_len; i++)
		fprintf(fout, "sid %s\n", initial_sid_to_string[i]);
	fprintf(fout, "\n");

	/* print out the class permissions */
	for (i = 0; secclass_map[i].name; i++) {
		struct security_class_mapping *map = &secclass_map[i];
		fprintf(fout, "class %s\n", map->name);
		fprintf(fout, "{\n");
		for (j = 0; map->perms[j]; j++)
			fprintf(fout, "\t%s\n", map->perms[j]);
		fprintf(fout, "}\n\n");
	}
	fprintf(fout, "\n");

	/* print out mls declarations and constraints */
	if (mls) {
		fprintf(fout, "sensitivity s0;\n");
		fprintf(fout, "sensitivity s1;\n");
		fprintf(fout, "dominance { s0 s1 }\n");
		fprintf(fout, "category c0;\n");
		fprintf(fout, "category c1;\n");
		fprintf(fout, "level s0:c0.c1;\n");
		fprintf(fout, "level s1:c0.c1;\n");
#define SYSTEMLOW "s0"
#define SYSTEMHIGH "s1:c0.c1"
		for (i = 0; secclass_map[i].name; i++) {
			struct security_class_mapping *map = &secclass_map[i];

			fprintf(fout, "mlsconstrain %s {\n", map->name);
			for (j = 0; map->perms[j]; j++)
				fprintf(fout, "\t%s\n", map->perms[j]);
			/*
			 * This requires all subjects and objects to be
			 * single-level (l2 eq h2), and that the subject
			 * level dominate the object level (h1 dom h2)
			 * in order to have any permissions to it.
			 */
			fprintf(fout, "} (l2 eq h2 and h1 dom h2);\n\n");
		}
	}

	/* types, roles, and allows */
	fprintf(fout, "type base_t;\n");
	fprintf(fout, "role base_r;\n");
	fprintf(fout, "role base_r types { base_t };\n");
	for (i = 0; secclass_map[i].name; i++)
		fprintf(fout, "allow base_t base_t:%s *;\n",
			secclass_map[i].name);
	fprintf(fout, "user user_u roles { base_r }");
	if (mls)
		fprintf(fout, " level %s range %s - %s", SYSTEMLOW,
			SYSTEMLOW, SYSTEMHIGH);
	fprintf(fout, ";\n");

#define SUBJUSERROLETYPE "user_u:base_r:base_t"
#define OBJUSERROLETYPE "user_u:object_r:base_t"

	/* default sids */
	for (i = 1; i < initial_sid_to_string_len; i++)
		fprintf(fout, "sid %s " SUBJUSERROLETYPE "%s\n",
			initial_sid_to_string[i], mls ? ":" SYSTEMLOW : "");
	fprintf(fout, "\n");

#define FS_USE(behavior, fstype)			    \
	fprintf(fout, "fs_use_%s %s " OBJUSERROLETYPE "%s;\n", \
		behavior, fstype, mls ? ":" SYSTEMLOW : "")

	/*
	 * Filesystems whose inode labels can be fetched via getxattr.
	 */
#ifdef CONFIG_EXT2_FS_SECURITY
	FS_USE("xattr", "ext2");
#endif
#ifdef CONFIG_EXT4_FS_SECURITY
#ifdef CONFIG_EXT4_USE_FOR_EXT2
	FS_USE("xattr", "ext2");
#endif
	FS_USE("xattr", "ext3");
	FS_USE("xattr", "ext4");
#endif
#ifdef CONFIG_JFS_SECURITY
	FS_USE("xattr", "jfs");
#endif
#ifdef CONFIG_REISERFS_FS_SECURITY
	FS_USE("xattr", "reiserfs");
#endif
#ifdef CONFIG_JFFS2_FS_SECURITY
	FS_USE("xattr", "jffs2");
#endif
#ifdef CONFIG_XFS_FS
	FS_USE("xattr", "xfs");
#endif
#ifdef CONFIG_GFS2_FS
	FS_USE("xattr", "gfs2");
#endif
#ifdef CONFIG_BTRFS_FS
	FS_USE("xattr", "btrfs");
#endif
#ifdef CONFIG_F2FS_FS_SECURITY
	FS_USE("xattr", "f2fs");
#endif
#ifdef CONFIG_OCFS2_FS
	FS_USE("xattr", "ocsfs2");
#endif
#ifdef CONFIG_OVERLAY_FS
	FS_USE("xattr", "overlay");
#endif
#ifdef CONFIG_SQUASHFS_XATTR
	FS_USE("xattr", "squashfs");
#endif

	/*
	 * Filesystems whose inodes are labeled from allocating task.
	 */
	FS_USE("task", "pipefs");
	FS_USE("task", "sockfs");

	/*
	 * Filesystems whose inode labels are computed from both
	 * the allocating task and the superblock label.
	 */
#ifdef CONFIG_UNIX98_PTYS
	FS_USE("trans", "devpts");
#endif
#ifdef CONFIG_HUGETLBFS
	FS_USE("trans", "hugetlbfs");
#endif
#ifdef CONFIG_TMPFS
	FS_USE("trans", "tmpfs");
#endif
#ifdef CONFIG_DEVTMPFS
	FS_USE("trans", "devtmpfs");
#endif
#ifdef CONFIG_POSIX_MQUEUE
	FS_USE("trans", "mqueue");
#endif

#define GENFSCON(fstype, prefix)			     \
	fprintf(fout, "genfscon %s %s " OBJUSERROLETYPE "%s\n", \
		fstype, prefix, mls ? ":" SYSTEMLOW : "")

	/*
	 * Filesystems whose inodes are labeled from path prefix match
	 * relative to the filesystem root.  Depending on the filesystem,
	 * only a single label for all inodes may be supported.  Here
	 * we list the filesystem types for which per-file labeling is
	 * supported using genfscon; any other filesystem type can also
	 * be added by only with a single entry for all of its inodes.
	 */
#ifdef CONFIG_PROC_FS
	GENFSCON("proc", "/");
#endif
#ifdef CONFIG_SECURITY_SELINUX
	GENFSCON("selinuxfs", "/");
#endif
#ifdef CONFIG_SYSFS
	GENFSCON("sysfs", "/");
#endif
#ifdef CONFIG_DEBUG_FS
	GENFSCON("debugfs", "/");
#endif
#ifdef CONFIG_TRACING
	GENFSCON("tracefs", "/");
#endif
#ifdef CONFIG_PSTORE
	GENFSCON("pstore", "/");
#endif
	GENFSCON("cgroup", "/");
	GENFSCON("cgroup2", "/");

	fclose(fout);

	fout = fopen(ctxout, "w");
	if (!fout) {
		printf("Wrote policy, but cannot open %s for writing\n", ctxout);
		usage(argv[0]);
	}
	fprintf(fout, "/ " OBJUSERROLETYPE "%s\n", mls ? ":" SYSTEMLOW : "");
	fprintf(fout, "/.* " OBJUSERROLETYPE "%s\n", mls ? ":" SYSTEMLOW : "");
	fclose(fout);

	return 0;
}