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Casey Schauflere114e472008-02-04 22:29:50 -08001/*
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>
Ahmed S. Darwish076c54c2008-03-06 18:09:10 +020018#include <linux/security.h>
Casey Schaufler6d3dc072008-12-31 12:54:12 -050019#include <linux/in.h>
Casey Schauflere114e472008-02-04 22:29:50 -080020#include <net/netlabel.h>
Etienne Basset7198e2e2009-03-24 20:53:24 +010021#include <linux/list.h>
22#include <linux/rculist.h>
Etienne Bassetecfcc532009-04-08 20:40:06 +020023#include <linux/lsm_audit.h>
Casey Schauflere114e472008-02-04 22:29:50 -080024
25/*
Casey Schauflerf7112e62012-05-06 15:22:02 -070026 * Smack labels were limited to 23 characters for a long time.
27 */
28#define SMK_LABELLEN 24
29#define SMK_LONGLABEL 256
30
31/*
Casey Schauflere114e472008-02-04 22:29:50 -080032 * This is the repository for labels seen so that it is
33 * not necessary to keep allocating tiny chuncks of memory
34 * and so that they can be shared.
35 *
36 * Labels are never modified in place. Anytime a label
37 * is imported (e.g. xattrset on a file) the list is checked
38 * for it and it is added if it doesn't exist. The address
39 * is passed out in either case. Entries are added, but
40 * never deleted.
41 *
42 * Since labels are hanging around anyway it doesn't
43 * hurt to maintain a secid for those awkward situations
44 * where kernel components that ought to use LSM independent
45 * interfaces don't. The secid should go away when all of
46 * these components have been repaired.
47 *
Casey Schauflerf7112e62012-05-06 15:22:02 -070048 * The cipso value associated with the label gets stored here, too.
Casey Schaufler272cd7a2011-09-20 12:24:36 -070049 *
50 * Keep the access rules for this subject label here so that
51 * the entire set of rules does not need to be examined every
52 * time.
Casey Schauflere114e472008-02-04 22:29:50 -080053 */
54struct smack_known {
Casey Schauflerf7112e62012-05-06 15:22:02 -070055 struct list_head list;
Tomasz Stanislawski4d7cf4a2013-06-11 14:55:13 +020056 struct hlist_node smk_hashed;
Casey Schauflerf7112e62012-05-06 15:22:02 -070057 char *smk_known;
58 u32 smk_secid;
59 struct netlbl_lsm_secattr smk_netlabel; /* on wire labels */
60 struct list_head smk_rules; /* access rules */
61 struct mutex smk_rules_lock; /* lock for rules */
Casey Schauflere114e472008-02-04 22:29:50 -080062};
63
64/*
Casey Schaufler2f823ff2013-05-22 18:43:03 -070065 * Maximum number of bytes for the levels in a CIPSO IP option.
66 * Why 23? CIPSO is constrained to 30, so a 32 byte buffer is
67 * bigger than can be used, and 24 is the next lower multiple
68 * of 8, and there are too many issues if there isn't space set
69 * aside for the terminating null byte.
70 */
71#define SMK_CIPSOLEN 24
72
73struct superblock_smack {
74 char *smk_root;
75 char *smk_floor;
76 char *smk_hat;
77 char *smk_default;
78 int smk_initialized;
79};
80
81struct socket_smack {
82 struct smack_known *smk_out; /* outbound label */
Casey Schaufler54e70ec2014-04-10 16:37:08 -070083 struct smack_known *smk_in; /* inbound label */
84 struct smack_known *smk_packet; /* TCP peer label */
Casey Schaufler2f823ff2013-05-22 18:43:03 -070085};
86
87/*
88 * Inode smack data
89 */
90struct inode_smack {
91 char *smk_inode; /* label of the fso */
92 struct smack_known *smk_task; /* label of the task */
93 struct smack_known *smk_mmap; /* label of the mmap domain */
94 struct mutex smk_lock; /* initialization lock */
95 int smk_flags; /* smack inode flags */
96};
97
98struct task_smack {
99 struct smack_known *smk_task; /* label for access control */
100 struct smack_known *smk_forked; /* label when forked */
101 struct list_head smk_rules; /* per task access rules */
102 struct mutex smk_rules_lock; /* lock for the rules */
103};
104
105#define SMK_INODE_INSTANT 0x01 /* inode is instantiated */
106#define SMK_INODE_TRANSMUTE 0x02 /* directory is transmuting */
107#define SMK_INODE_CHANGED 0x04 /* smack was transmuted */
108
109/*
110 * A label access rule.
111 */
112struct smack_rule {
113 struct list_head list;
114 struct smack_known *smk_subject;
115 char *smk_object;
116 int smk_access;
117};
118
119/*
120 * An entry in the table identifying hosts.
121 */
122struct smk_netlbladdr {
123 struct list_head list;
124 struct sockaddr_in smk_host; /* network address */
125 struct in_addr smk_mask; /* network mask */
126 char *smk_label; /* label */
127};
128
129/*
130 * An entry in the table identifying ports.
131 */
132struct smk_port_label {
133 struct list_head list;
134 struct sock *smk_sock; /* socket initialized on */
135 unsigned short smk_port; /* the port number */
Casey Schaufler54e70ec2014-04-10 16:37:08 -0700136 struct smack_known *smk_in; /* inbound label */
Casey Schaufler2f823ff2013-05-22 18:43:03 -0700137 struct smack_known *smk_out; /* outgoing label */
138};
139
140/*
Casey Schauflere114e472008-02-04 22:29:50 -0800141 * Mount options
142 */
143#define SMK_FSDEFAULT "smackfsdef="
144#define SMK_FSFLOOR "smackfsfloor="
145#define SMK_FSHAT "smackfshat="
146#define SMK_FSROOT "smackfsroot="
Casey Schauflere830b392013-05-22 18:43:07 -0700147#define SMK_FSTRANS "smackfstransmute="
Casey Schauflere114e472008-02-04 22:29:50 -0800148
Etienne Basset43031542009-03-27 17:11:01 -0400149#define SMACK_CIPSO_OPTION "-CIPSO"
150
Casey Schauflere114e472008-02-04 22:29:50 -0800151/*
Casey Schaufler6d3dc072008-12-31 12:54:12 -0500152 * How communications on this socket are treated.
153 * Usually it's determined by the underlying netlabel code
154 * but there are certain cases, including single label hosts
155 * and potentially single label interfaces for which the
156 * treatment can not be known in advance.
157 *
158 * The possibility of additional labeling schemes being
159 * introduced in the future exists as well.
160 */
161#define SMACK_UNLABELED_SOCKET 0
162#define SMACK_CIPSO_SOCKET 1
163
164/*
Casey Schauflere114e472008-02-04 22:29:50 -0800165 * CIPSO defaults.
166 */
167#define SMACK_CIPSO_DOI_DEFAULT 3 /* Historical */
Casey Schaufler6d3dc072008-12-31 12:54:12 -0500168#define SMACK_CIPSO_DOI_INVALID -1 /* Not a DOI */
Casey Schauflere114e472008-02-04 22:29:50 -0800169#define SMACK_CIPSO_DIRECT_DEFAULT 250 /* Arbitrary */
Casey Schauflerf7112e62012-05-06 15:22:02 -0700170#define SMACK_CIPSO_MAPPED_DEFAULT 251 /* Also arbitrary */
Casey Schauflere114e472008-02-04 22:29:50 -0800171#define SMACK_CIPSO_MAXLEVEL 255 /* CIPSO 2.2 standard */
Casey Schaufler677264e2013-06-28 13:47:07 -0700172/*
173 * CIPSO 2.2 standard is 239, but Smack wants to use the
174 * categories in a structured way that limits the value to
175 * the bits in 23 bytes, hence the unusual number.
176 */
177#define SMACK_CIPSO_MAXCATNUM 184 /* 23 * 8 */
Casey Schauflere114e472008-02-04 22:29:50 -0800178
179/*
Lukasz Pawelczyk66867812014-03-11 17:07:06 +0100180 * Ptrace rules
181 */
182#define SMACK_PTRACE_DEFAULT 0
183#define SMACK_PTRACE_EXACT 1
184#define SMACK_PTRACE_DRACONIAN 2
185#define SMACK_PTRACE_MAX SMACK_PTRACE_DRACONIAN
186
187/*
Casey Schauflerc0ab6e52013-10-11 18:06:39 -0700188 * Flags for untraditional access modes.
189 * It shouldn't be necessary to avoid conflicts with definitions
190 * in fs.h, but do so anyway.
Jarkko Sakkinen5c6d1122010-12-07 13:34:01 +0200191 */
Casey Schauflerc0ab6e52013-10-11 18:06:39 -0700192#define MAY_TRANSMUTE 0x00001000 /* Controls directory labeling */
193#define MAY_LOCK 0x00002000 /* Locks should be writes, but ... */
194
Jarkko Sakkinen5c6d1122010-12-07 13:34:01 +0200195/*
Casey Schauflere114e472008-02-04 22:29:50 -0800196 * Just to make the common cases easier to deal with
197 */
Casey Schauflere114e472008-02-04 22:29:50 -0800198#define MAY_ANYREAD (MAY_READ | MAY_EXEC)
Casey Schauflere114e472008-02-04 22:29:50 -0800199#define MAY_READWRITE (MAY_READ | MAY_WRITE)
200#define MAY_NOT 0
201
202/*
Casey Schauflerc0ab6e52013-10-11 18:06:39 -0700203 * Number of access types used by Smack (rwxatl)
Etienne Bassetecfcc532009-04-08 20:40:06 +0200204 */
Casey Schauflerc0ab6e52013-10-11 18:06:39 -0700205#define SMK_NUM_ACCESS_TYPE 6
Etienne Bassetecfcc532009-04-08 20:40:06 +0200206
Eric Paris3b3b0e42012-04-03 09:37:02 -0700207/* SMACK data */
208struct smack_audit_data {
209 const char *function;
210 char *subject;
211 char *object;
212 char *request;
213 int result;
214};
215
Etienne Bassetecfcc532009-04-08 20:40:06 +0200216/*
217 * Smack audit data; is empty if CONFIG_AUDIT not set
218 * to save some stack
219 */
220struct smk_audit_info {
221#ifdef CONFIG_AUDIT
222 struct common_audit_data a;
Eric Paris3b3b0e42012-04-03 09:37:02 -0700223 struct smack_audit_data sad;
Etienne Bassetecfcc532009-04-08 20:40:06 +0200224#endif
225};
226/*
Casey Schauflere114e472008-02-04 22:29:50 -0800227 * These functions are in smack_lsm.c
228 */
229struct inode_smack *new_inode_smack(char *);
230
231/*
232 * These functions are in smack_access.c
233 */
Casey Schaufler7898e1f2011-01-17 08:05:27 -0800234int smk_access_entry(char *, char *, struct list_head *);
Casey Schaufler2f823ff2013-05-22 18:43:03 -0700235int smk_access(struct smack_known *, char *, int, struct smk_audit_info *);
Lukasz Pawelczyk959e6c72014-03-11 17:07:04 +0100236int smk_tskacc(struct task_smack *, char *, u32, struct smk_audit_info *);
Etienne Bassetecfcc532009-04-08 20:40:06 +0200237int smk_curacc(char *, u32, struct smk_audit_info *);
Casey Schaufler2f823ff2013-05-22 18:43:03 -0700238struct smack_known *smack_from_secid(const u32);
Casey Schauflerf7112e62012-05-06 15:22:02 -0700239char *smk_parse_smack(const char *string, int len);
240int smk_netlbl_mls(int, char *, struct netlbl_lsm_secattr *, int);
Casey Schauflere114e472008-02-04 22:29:50 -0800241char *smk_import(const char *, int);
242struct smack_known *smk_import_entry(const char *, int);
Tomasz Stanislawski4d7cf4a2013-06-11 14:55:13 +0200243void smk_insert_entry(struct smack_known *skp);
Casey Schaufler272cd7a2011-09-20 12:24:36 -0700244struct smack_known *smk_find_entry(const char *);
Casey Schauflere114e472008-02-04 22:29:50 -0800245u32 smack_to_secid(const char *);
246
247/*
248 * Shared data.
249 */
250extern int smack_cipso_direct;
Casey Schauflerf7112e62012-05-06 15:22:02 -0700251extern int smack_cipso_mapped;
Casey Schaufler2f823ff2013-05-22 18:43:03 -0700252extern struct smack_known *smack_net_ambient;
Casey Schaufler00f84f32013-12-23 11:07:10 -0800253extern struct smack_known *smack_onlycap;
254extern struct smack_known *smack_syslog_label;
Etienne Basset43031542009-03-27 17:11:01 -0400255extern const char *smack_cipso_option;
Lukasz Pawelczyk66867812014-03-11 17:07:06 +0100256extern int smack_ptrace_rule;
Casey Schauflere114e472008-02-04 22:29:50 -0800257
Casey Schauflere114e472008-02-04 22:29:50 -0800258extern struct smack_known smack_known_floor;
259extern struct smack_known smack_known_hat;
260extern struct smack_known smack_known_huh;
261extern struct smack_known smack_known_invalid;
262extern struct smack_known smack_known_star;
Casey Schaufler6d3dc072008-12-31 12:54:12 -0500263extern struct smack_known smack_known_web;
Casey Schauflere114e472008-02-04 22:29:50 -0800264
Casey Schauflerf7112e62012-05-06 15:22:02 -0700265extern struct mutex smack_known_lock;
Etienne Basset7198e2e2009-03-24 20:53:24 +0100266extern struct list_head smack_known_list;
Etienne Basset7198e2e2009-03-24 20:53:24 +0100267extern struct list_head smk_netlbladdr_list;
268
Ahmed S. Darwish076c54c2008-03-06 18:09:10 +0200269extern struct security_operations smack_ops;
Casey Schauflere114e472008-02-04 22:29:50 -0800270
Tomasz Stanislawski4d7cf4a2013-06-11 14:55:13 +0200271#define SMACK_HASH_SLOTS 16
272extern struct hlist_head smack_known_hash[SMACK_HASH_SLOTS];
273
Casey Schauflere114e472008-02-04 22:29:50 -0800274/*
Jarkko Sakkinen5c6d1122010-12-07 13:34:01 +0200275 * Is the directory transmuting?
276 */
277static inline int smk_inode_transmutable(const struct inode *isp)
278{
279 struct inode_smack *sip = isp->i_security;
280 return (sip->smk_flags & SMK_INODE_TRANSMUTE) != 0;
281}
282
283/*
Casey Schauflere114e472008-02-04 22:29:50 -0800284 * Present a pointer to the smack label in an inode blob.
285 */
286static inline char *smk_of_inode(const struct inode *isp)
287{
288 struct inode_smack *sip = isp->i_security;
289 return sip->smk_inode;
290}
291
Etienne Bassetecfcc532009-04-08 20:40:06 +0200292/*
Casey Schaufler2f823ff2013-05-22 18:43:03 -0700293 * Present a pointer to the smack label entry in an task blob.
Casey Schaufler676dac42010-12-02 06:43:39 -0800294 */
Casey Schaufler2f823ff2013-05-22 18:43:03 -0700295static inline struct smack_known *smk_of_task(const struct task_smack *tsp)
Casey Schaufler676dac42010-12-02 06:43:39 -0800296{
297 return tsp->smk_task;
298}
299
300/*
Casey Schaufler2f823ff2013-05-22 18:43:03 -0700301 * Present a pointer to the forked smack label entry in an task blob.
Casey Schaufler676dac42010-12-02 06:43:39 -0800302 */
Casey Schaufler2f823ff2013-05-22 18:43:03 -0700303static inline struct smack_known *smk_of_forked(const struct task_smack *tsp)
Casey Schaufler676dac42010-12-02 06:43:39 -0800304{
305 return tsp->smk_forked;
306}
307
308/*
Jarkko Sakkinen5c6d1122010-12-07 13:34:01 +0200309 * Present a pointer to the smack label in the current task blob.
Casey Schaufler676dac42010-12-02 06:43:39 -0800310 */
Casey Schaufler2f823ff2013-05-22 18:43:03 -0700311static inline struct smack_known *smk_of_current(void)
Casey Schaufler676dac42010-12-02 06:43:39 -0800312{
313 return smk_of_task(current_security());
314}
315
316/*
Casey Schaufler1880eff2012-06-05 15:28:30 -0700317 * Is the task privileged and allowed to be privileged
318 * by the onlycap rule.
319 */
320static inline int smack_privileged(int cap)
321{
Casey Schaufler2f823ff2013-05-22 18:43:03 -0700322 struct smack_known *skp = smk_of_current();
323
Casey Schaufler1880eff2012-06-05 15:28:30 -0700324 if (!capable(cap))
325 return 0;
Casey Schaufler00f84f32013-12-23 11:07:10 -0800326 if (smack_onlycap == NULL || smack_onlycap == skp)
Casey Schaufler1880eff2012-06-05 15:28:30 -0700327 return 1;
328 return 0;
329}
330
331/*
Etienne Bassetecfcc532009-04-08 20:40:06 +0200332 * logging functions
333 */
334#define SMACK_AUDIT_DENIED 0x1
335#define SMACK_AUDIT_ACCEPT 0x2
336extern int log_policy;
337
338void smack_log(char *subject_label, char *object_label,
339 int request,
340 int result, struct smk_audit_info *auditdata);
341
342#ifdef CONFIG_AUDIT
343
344/*
345 * some inline functions to set up audit data
346 * they do nothing if CONFIG_AUDIT is not set
347 *
348 */
349static inline void smk_ad_init(struct smk_audit_info *a, const char *func,
350 char type)
351{
Eric Paris50c205f2012-04-04 15:01:43 -0400352 memset(&a->sad, 0, sizeof(a->sad));
Etienne Bassetecfcc532009-04-08 20:40:06 +0200353 a->a.type = type;
Eric Paris3b3b0e42012-04-03 09:37:02 -0700354 a->a.smack_audit_data = &a->sad;
355 a->a.smack_audit_data->function = func;
Etienne Bassetecfcc532009-04-08 20:40:06 +0200356}
357
Eric Paris48c62af2012-04-02 13:15:44 -0400358static inline void smk_ad_init_net(struct smk_audit_info *a, const char *func,
359 char type, struct lsm_network_audit *net)
360{
361 smk_ad_init(a, func, type);
362 memset(net, 0, sizeof(*net));
363 a->a.u.net = net;
364}
365
Etienne Bassetecfcc532009-04-08 20:40:06 +0200366static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a,
367 struct task_struct *t)
368{
369 a->a.u.tsk = t;
370}
371static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a,
372 struct dentry *d)
373{
Eric Parisa2694342011-04-25 13:10:27 -0400374 a->a.u.dentry = d;
Etienne Bassetecfcc532009-04-08 20:40:06 +0200375}
376static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a,
377 struct inode *i)
378{
Eric Parisf48b7392011-04-25 12:54:27 -0400379 a->a.u.inode = i;
Etienne Bassetecfcc532009-04-08 20:40:06 +0200380}
381static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a,
382 struct path p)
383{
Eric Parisf48b7392011-04-25 12:54:27 -0400384 a->a.u.path = p;
Etienne Bassetecfcc532009-04-08 20:40:06 +0200385}
386static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a,
387 struct sock *sk)
388{
Eric Paris48c62af2012-04-02 13:15:44 -0400389 a->a.u.net->sk = sk;
Etienne Bassetecfcc532009-04-08 20:40:06 +0200390}
391
392#else /* no AUDIT */
393
394static inline void smk_ad_init(struct smk_audit_info *a, const char *func,
395 char type)
396{
397}
398static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a,
399 struct task_struct *t)
400{
401}
402static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a,
403 struct dentry *d)
404{
405}
406static inline void smk_ad_setfield_u_fs_path_mnt(struct smk_audit_info *a,
407 struct vfsmount *m)
408{
409}
410static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a,
411 struct inode *i)
412{
413}
414static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a,
415 struct path p)
416{
417}
418static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a,
419 struct sock *sk)
420{
421}
422#endif
423
Casey Schauflere114e472008-02-04 22:29:50 -0800424#endif /* _SECURITY_SMACK_H */