Merge tag 'please-pull-mce' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras
[deliverable/linux.git] / security / smack / smack.h
1 /*
2 * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation, version 2.
7 *
8 * Author:
9 * Casey Schaufler <casey@schaufler-ca.com>
10 *
11 */
12
13 #ifndef _SECURITY_SMACK_H
14 #define _SECURITY_SMACK_H
15
16 #include <linux/capability.h>
17 #include <linux/spinlock.h>
18 #include <linux/security.h>
19 #include <linux/in.h>
20 #include <net/netlabel.h>
21 #include <linux/list.h>
22 #include <linux/rculist.h>
23 #include <linux/lsm_audit.h>
24
25 /*
26 * Smack labels were limited to 23 characters for a long time.
27 */
28 #define SMK_LABELLEN 24
29 #define SMK_LONGLABEL 256
30
31 /*
32 * Maximum number of bytes for the levels in a CIPSO IP option.
33 * Why 23? CIPSO is constrained to 30, so a 32 byte buffer is
34 * bigger than can be used, and 24 is the next lower multiple
35 * of 8, and there are too many issues if there isn't space set
36 * aside for the terminating null byte.
37 */
38 #define SMK_CIPSOLEN 24
39
40 struct superblock_smack {
41 char *smk_root;
42 char *smk_floor;
43 char *smk_hat;
44 char *smk_default;
45 int smk_initialized;
46 spinlock_t smk_sblock; /* for initialization */
47 };
48
49 struct socket_smack {
50 char *smk_out; /* outbound label */
51 char *smk_in; /* inbound label */
52 char *smk_packet; /* TCP peer label */
53 };
54
55 /*
56 * Inode smack data
57 */
58 struct inode_smack {
59 char *smk_inode; /* label of the fso */
60 char *smk_task; /* label of the task */
61 char *smk_mmap; /* label of the mmap domain */
62 struct mutex smk_lock; /* initialization lock */
63 int smk_flags; /* smack inode flags */
64 };
65
66 struct task_smack {
67 char *smk_task; /* label for access control */
68 char *smk_forked; /* label when forked */
69 struct list_head smk_rules; /* per task access rules */
70 struct mutex smk_rules_lock; /* lock for the rules */
71 };
72
73 #define SMK_INODE_INSTANT 0x01 /* inode is instantiated */
74 #define SMK_INODE_TRANSMUTE 0x02 /* directory is transmuting */
75 #define SMK_INODE_CHANGED 0x04 /* smack was transmuted */
76
77 /*
78 * A label access rule.
79 */
80 struct smack_rule {
81 struct list_head list;
82 char *smk_subject;
83 char *smk_object;
84 int smk_access;
85 };
86
87 /*
88 * An entry in the table identifying hosts.
89 */
90 struct smk_netlbladdr {
91 struct list_head list;
92 struct sockaddr_in smk_host; /* network address */
93 struct in_addr smk_mask; /* network mask */
94 char *smk_label; /* label */
95 };
96
97 /*
98 * This is the repository for labels seen so that it is
99 * not necessary to keep allocating tiny chuncks of memory
100 * and so that they can be shared.
101 *
102 * Labels are never modified in place. Anytime a label
103 * is imported (e.g. xattrset on a file) the list is checked
104 * for it and it is added if it doesn't exist. The address
105 * is passed out in either case. Entries are added, but
106 * never deleted.
107 *
108 * Since labels are hanging around anyway it doesn't
109 * hurt to maintain a secid for those awkward situations
110 * where kernel components that ought to use LSM independent
111 * interfaces don't. The secid should go away when all of
112 * these components have been repaired.
113 *
114 * The cipso value associated with the label gets stored here, too.
115 *
116 * Keep the access rules for this subject label here so that
117 * the entire set of rules does not need to be examined every
118 * time.
119 */
120 struct smack_known {
121 struct list_head list;
122 char *smk_known;
123 u32 smk_secid;
124 struct netlbl_lsm_secattr smk_netlabel; /* on wire labels */
125 struct list_head smk_rules; /* access rules */
126 struct mutex smk_rules_lock; /* lock for rules */
127 };
128
129 /*
130 * Mount options
131 */
132 #define SMK_FSDEFAULT "smackfsdef="
133 #define SMK_FSFLOOR "smackfsfloor="
134 #define SMK_FSHAT "smackfshat="
135 #define SMK_FSROOT "smackfsroot="
136
137 #define SMACK_CIPSO_OPTION "-CIPSO"
138
139 /*
140 * How communications on this socket are treated.
141 * Usually it's determined by the underlying netlabel code
142 * but there are certain cases, including single label hosts
143 * and potentially single label interfaces for which the
144 * treatment can not be known in advance.
145 *
146 * The possibility of additional labeling schemes being
147 * introduced in the future exists as well.
148 */
149 #define SMACK_UNLABELED_SOCKET 0
150 #define SMACK_CIPSO_SOCKET 1
151
152 /*
153 * smackfs magic number
154 */
155 #define SMACK_MAGIC 0x43415d53 /* "SMAC" */
156
157 /*
158 * CIPSO defaults.
159 */
160 #define SMACK_CIPSO_DOI_DEFAULT 3 /* Historical */
161 #define SMACK_CIPSO_DOI_INVALID -1 /* Not a DOI */
162 #define SMACK_CIPSO_DIRECT_DEFAULT 250 /* Arbitrary */
163 #define SMACK_CIPSO_MAPPED_DEFAULT 251 /* Also arbitrary */
164 #define SMACK_CIPSO_MAXCATVAL 63 /* Bigger gets harder */
165 #define SMACK_CIPSO_MAXLEVEL 255 /* CIPSO 2.2 standard */
166 #define SMACK_CIPSO_MAXCATNUM 239 /* CIPSO 2.2 standard */
167
168 /*
169 * Flag for transmute access
170 */
171 #define MAY_TRANSMUTE 64
172 /*
173 * Just to make the common cases easier to deal with
174 */
175 #define MAY_ANYREAD (MAY_READ | MAY_EXEC)
176 #define MAY_READWRITE (MAY_READ | MAY_WRITE)
177 #define MAY_NOT 0
178
179 /*
180 * Number of access types used by Smack (rwxat)
181 */
182 #define SMK_NUM_ACCESS_TYPE 5
183
184 /* SMACK data */
185 struct smack_audit_data {
186 const char *function;
187 char *subject;
188 char *object;
189 char *request;
190 int result;
191 };
192
193 /*
194 * Smack audit data; is empty if CONFIG_AUDIT not set
195 * to save some stack
196 */
197 struct smk_audit_info {
198 #ifdef CONFIG_AUDIT
199 struct common_audit_data a;
200 struct smack_audit_data sad;
201 #endif
202 };
203 /*
204 * These functions are in smack_lsm.c
205 */
206 struct inode_smack *new_inode_smack(char *);
207
208 /*
209 * These functions are in smack_access.c
210 */
211 int smk_access_entry(char *, char *, struct list_head *);
212 int smk_access(char *, char *, int, struct smk_audit_info *);
213 int smk_curacc(char *, u32, struct smk_audit_info *);
214 char *smack_from_secid(const u32);
215 char *smk_parse_smack(const char *string, int len);
216 int smk_netlbl_mls(int, char *, struct netlbl_lsm_secattr *, int);
217 char *smk_import(const char *, int);
218 struct smack_known *smk_import_entry(const char *, int);
219 struct smack_known *smk_find_entry(const char *);
220 u32 smack_to_secid(const char *);
221
222 /*
223 * Shared data.
224 */
225 extern int smack_cipso_direct;
226 extern int smack_cipso_mapped;
227 extern char *smack_net_ambient;
228 extern char *smack_onlycap;
229 extern const char *smack_cipso_option;
230
231 extern struct smack_known smack_known_floor;
232 extern struct smack_known smack_known_hat;
233 extern struct smack_known smack_known_huh;
234 extern struct smack_known smack_known_invalid;
235 extern struct smack_known smack_known_star;
236 extern struct smack_known smack_known_web;
237
238 extern struct mutex smack_known_lock;
239 extern struct list_head smack_known_list;
240 extern struct list_head smk_netlbladdr_list;
241
242 extern struct security_operations smack_ops;
243
244 /*
245 * Is the directory transmuting?
246 */
247 static inline int smk_inode_transmutable(const struct inode *isp)
248 {
249 struct inode_smack *sip = isp->i_security;
250 return (sip->smk_flags & SMK_INODE_TRANSMUTE) != 0;
251 }
252
253 /*
254 * Present a pointer to the smack label in an inode blob.
255 */
256 static inline char *smk_of_inode(const struct inode *isp)
257 {
258 struct inode_smack *sip = isp->i_security;
259 return sip->smk_inode;
260 }
261
262 /*
263 * Present a pointer to the smack label in an task blob.
264 */
265 static inline char *smk_of_task(const struct task_smack *tsp)
266 {
267 return tsp->smk_task;
268 }
269
270 /*
271 * Present a pointer to the forked smack label in an task blob.
272 */
273 static inline char *smk_of_forked(const struct task_smack *tsp)
274 {
275 return tsp->smk_forked;
276 }
277
278 /*
279 * Present a pointer to the smack label in the current task blob.
280 */
281 static inline char *smk_of_current(void)
282 {
283 return smk_of_task(current_security());
284 }
285
286 /*
287 * logging functions
288 */
289 #define SMACK_AUDIT_DENIED 0x1
290 #define SMACK_AUDIT_ACCEPT 0x2
291 extern int log_policy;
292
293 void smack_log(char *subject_label, char *object_label,
294 int request,
295 int result, struct smk_audit_info *auditdata);
296
297 #ifdef CONFIG_AUDIT
298
299 /*
300 * some inline functions to set up audit data
301 * they do nothing if CONFIG_AUDIT is not set
302 *
303 */
304 static inline void smk_ad_init(struct smk_audit_info *a, const char *func,
305 char type)
306 {
307 memset(&a->sad, 0, sizeof(a->sad));
308 a->a.type = type;
309 a->a.smack_audit_data = &a->sad;
310 a->a.smack_audit_data->function = func;
311 }
312
313 static inline void smk_ad_init_net(struct smk_audit_info *a, const char *func,
314 char type, struct lsm_network_audit *net)
315 {
316 smk_ad_init(a, func, type);
317 memset(net, 0, sizeof(*net));
318 a->a.u.net = net;
319 }
320
321 static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a,
322 struct task_struct *t)
323 {
324 a->a.u.tsk = t;
325 }
326 static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a,
327 struct dentry *d)
328 {
329 a->a.u.dentry = d;
330 }
331 static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a,
332 struct inode *i)
333 {
334 a->a.u.inode = i;
335 }
336 static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a,
337 struct path p)
338 {
339 a->a.u.path = p;
340 }
341 static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a,
342 struct sock *sk)
343 {
344 a->a.u.net->sk = sk;
345 }
346
347 #else /* no AUDIT */
348
349 static inline void smk_ad_init(struct smk_audit_info *a, const char *func,
350 char type)
351 {
352 }
353 static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a,
354 struct task_struct *t)
355 {
356 }
357 static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a,
358 struct dentry *d)
359 {
360 }
361 static inline void smk_ad_setfield_u_fs_path_mnt(struct smk_audit_info *a,
362 struct vfsmount *m)
363 {
364 }
365 static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a,
366 struct inode *i)
367 {
368 }
369 static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a,
370 struct path p)
371 {
372 }
373 static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a,
374 struct sock *sk)
375 {
376 }
377 #endif
378
379 #endif /* _SECURITY_SMACK_H */
This page took 0.038962 seconds and 6 git commands to generate.