xref: /linux/kernel/audit.h (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /* audit -- definition of audit_context structure and supporting types
2  *
3  * Copyright 2003-2004 Red Hat, Inc.
4  * Copyright 2005 Hewlett-Packard Development Company, L.P.
5  * Copyright 2005 IBM Corporation
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
20  */
21 
22 #include <linux/fs.h>
23 #include <linux/audit.h>
24 #include <linux/skbuff.h>
25 #include <uapi/linux/mqueue.h>
26 
27 /* AUDIT_NAMES is the number of slots we reserve in the audit_context
28  * for saving names from getname().  If we get more names we will allocate
29  * a name dynamically and also add those to the list anchored by names_list. */
30 #define AUDIT_NAMES	5
31 
32 /* At task start time, the audit_state is set in the audit_context using
33    a per-task filter.  At syscall entry, the audit_state is augmented by
34    the syscall filter. */
35 enum audit_state {
36 	AUDIT_DISABLED,		/* Do not create per-task audit_context.
37 				 * No syscall-specific audit records can
38 				 * be generated. */
39 	AUDIT_BUILD_CONTEXT,	/* Create the per-task audit_context,
40 				 * and fill it in at syscall
41 				 * entry time.  This makes a full
42 				 * syscall record available if some
43 				 * other part of the kernel decides it
44 				 * should be recorded. */
45 	AUDIT_RECORD_CONTEXT	/* Create the per-task audit_context,
46 				 * always fill it in at syscall entry
47 				 * time, and always write out the audit
48 				 * record at syscall exit time.  */
49 };
50 
51 /* Rule lists */
52 struct audit_watch;
53 struct audit_fsnotify_mark;
54 struct audit_tree;
55 struct audit_chunk;
56 
57 struct audit_entry {
58 	struct list_head	list;
59 	struct rcu_head		rcu;
60 	struct audit_krule	rule;
61 };
62 
63 struct audit_cap_data {
64 	kernel_cap_t		permitted;
65 	kernel_cap_t		inheritable;
66 	union {
67 		unsigned int	fE;		/* effective bit of file cap */
68 		kernel_cap_t	effective;	/* effective set of process */
69 	};
70 };
71 
72 /* When fs/namei.c:getname() is called, we store the pointer in name and bump
73  * the refcnt in the associated filename struct.
74  *
75  * Further, in fs/namei.c:path_lookup() we store the inode and device.
76  */
77 struct audit_names {
78 	struct list_head	list;		/* audit_context->names_list */
79 
80 	struct filename		*name;
81 	int			name_len;	/* number of chars to log */
82 	bool			hidden;		/* don't log this record */
83 
84 	unsigned long		ino;
85 	dev_t			dev;
86 	umode_t			mode;
87 	kuid_t			uid;
88 	kgid_t			gid;
89 	dev_t			rdev;
90 	u32			osid;
91 	struct audit_cap_data	fcap;
92 	unsigned int		fcap_ver;
93 	unsigned char		type;		/* record type */
94 	/*
95 	 * This was an allocated audit_names and not from the array of
96 	 * names allocated in the task audit context.  Thus this name
97 	 * should be freed on syscall exit.
98 	 */
99 	bool			should_free;
100 };
101 
102 struct audit_proctitle {
103 	int	len;	/* length of the cmdline field. */
104 	char	*value;	/* the cmdline field */
105 };
106 
107 /* The per-task audit context. */
108 struct audit_context {
109 	int		    dummy;	/* must be the first element */
110 	int		    in_syscall;	/* 1 if task is in a syscall */
111 	enum audit_state    state, current_state;
112 	unsigned int	    serial;     /* serial number for record */
113 	int		    major;      /* syscall number */
114 	struct timespec	    ctime;      /* time of syscall entry */
115 	unsigned long	    argv[4];    /* syscall arguments */
116 	long		    return_code;/* syscall return code */
117 	u64		    prio;
118 	int		    return_valid; /* return code is valid */
119 	/*
120 	 * The names_list is the list of all audit_names collected during this
121 	 * syscall.  The first AUDIT_NAMES entries in the names_list will
122 	 * actually be from the preallocated_names array for performance
123 	 * reasons.  Except during allocation they should never be referenced
124 	 * through the preallocated_names array and should only be found/used
125 	 * by running the names_list.
126 	 */
127 	struct audit_names  preallocated_names[AUDIT_NAMES];
128 	int		    name_count; /* total records in names_list */
129 	struct list_head    names_list;	/* struct audit_names->list anchor */
130 	char		    *filterkey;	/* key for rule that triggered record */
131 	struct path	    pwd;
132 	struct audit_aux_data *aux;
133 	struct audit_aux_data *aux_pids;
134 	struct sockaddr_storage *sockaddr;
135 	size_t sockaddr_len;
136 				/* Save things to print about task_struct */
137 	pid_t		    pid, ppid;
138 	kuid_t		    uid, euid, suid, fsuid;
139 	kgid_t		    gid, egid, sgid, fsgid;
140 	unsigned long	    personality;
141 	int		    arch;
142 
143 	pid_t		    target_pid;
144 	kuid_t		    target_auid;
145 	kuid_t		    target_uid;
146 	unsigned int	    target_sessionid;
147 	u32		    target_sid;
148 	char		    target_comm[TASK_COMM_LEN];
149 
150 	struct audit_tree_refs *trees, *first_trees;
151 	struct list_head killed_trees;
152 	int tree_count;
153 
154 	int type;
155 	union {
156 		struct {
157 			int nargs;
158 			long args[6];
159 		} socketcall;
160 		struct {
161 			kuid_t			uid;
162 			kgid_t			gid;
163 			umode_t			mode;
164 			u32			osid;
165 			int			has_perm;
166 			uid_t			perm_uid;
167 			gid_t			perm_gid;
168 			umode_t			perm_mode;
169 			unsigned long		qbytes;
170 		} ipc;
171 		struct {
172 			mqd_t			mqdes;
173 			struct mq_attr		mqstat;
174 		} mq_getsetattr;
175 		struct {
176 			mqd_t			mqdes;
177 			int			sigev_signo;
178 		} mq_notify;
179 		struct {
180 			mqd_t			mqdes;
181 			size_t			msg_len;
182 			unsigned int		msg_prio;
183 			struct timespec		abs_timeout;
184 		} mq_sendrecv;
185 		struct {
186 			int			oflag;
187 			umode_t			mode;
188 			struct mq_attr		attr;
189 		} mq_open;
190 		struct {
191 			pid_t			pid;
192 			struct audit_cap_data	cap;
193 		} capset;
194 		struct {
195 			int			fd;
196 			int			flags;
197 		} mmap;
198 		struct {
199 			int			argc;
200 		} execve;
201 	};
202 	int fds[2];
203 	struct audit_proctitle proctitle;
204 };
205 
206 extern u32 audit_ever_enabled;
207 
208 extern void audit_copy_inode(struct audit_names *name,
209 			     const struct dentry *dentry,
210 			     const struct inode *inode);
211 extern void audit_log_cap(struct audit_buffer *ab, char *prefix,
212 			  kernel_cap_t *cap);
213 extern void audit_log_name(struct audit_context *context,
214 			   struct audit_names *n, struct path *path,
215 			   int record_num, int *call_panic);
216 
217 extern int audit_pid;
218 
219 #define AUDIT_INODE_BUCKETS	32
220 extern struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS];
221 
222 static inline int audit_hash_ino(u32 ino)
223 {
224 	return (ino & (AUDIT_INODE_BUCKETS-1));
225 }
226 
227 /* Indicates that audit should log the full pathname. */
228 #define AUDIT_NAME_FULL -1
229 
230 extern int audit_match_class(int class, unsigned syscall);
231 extern int audit_comparator(const u32 left, const u32 op, const u32 right);
232 extern int audit_uid_comparator(kuid_t left, u32 op, kuid_t right);
233 extern int audit_gid_comparator(kgid_t left, u32 op, kgid_t right);
234 extern int parent_len(const char *path);
235 extern int audit_compare_dname_path(const char *dname, const char *path, int plen);
236 extern struct sk_buff *audit_make_reply(__u32 portid, int seq, int type,
237 					int done, int multi,
238 					const void *payload, int size);
239 extern void		    audit_panic(const char *message);
240 
241 struct audit_netlink_list {
242 	__u32 portid;
243 	struct net *net;
244 	struct sk_buff_head q;
245 };
246 
247 int audit_send_list(void *);
248 
249 struct audit_net {
250 	struct sock *nlsk;
251 };
252 
253 extern int selinux_audit_rule_update(void);
254 
255 extern struct mutex audit_filter_mutex;
256 extern int audit_del_rule(struct audit_entry *);
257 extern void audit_free_rule_rcu(struct rcu_head *);
258 extern struct list_head audit_filter_list[];
259 
260 extern struct audit_entry *audit_dupe_rule(struct audit_krule *old);
261 
262 extern void audit_log_d_path_exe(struct audit_buffer *ab,
263 				 struct mm_struct *mm);
264 
265 /* audit watch functions */
266 #ifdef CONFIG_AUDIT_WATCH
267 extern void audit_put_watch(struct audit_watch *watch);
268 extern void audit_get_watch(struct audit_watch *watch);
269 extern int audit_to_watch(struct audit_krule *krule, char *path, int len, u32 op);
270 extern int audit_add_watch(struct audit_krule *krule, struct list_head **list);
271 extern void audit_remove_watch_rule(struct audit_krule *krule);
272 extern char *audit_watch_path(struct audit_watch *watch);
273 extern int audit_watch_compare(struct audit_watch *watch, unsigned long ino, dev_t dev);
274 
275 extern struct audit_fsnotify_mark *audit_alloc_mark(struct audit_krule *krule, char *pathname, int len);
276 extern char *audit_mark_path(struct audit_fsnotify_mark *mark);
277 extern void audit_remove_mark(struct audit_fsnotify_mark *audit_mark);
278 extern void audit_remove_mark_rule(struct audit_krule *krule);
279 extern int audit_mark_compare(struct audit_fsnotify_mark *mark, unsigned long ino, dev_t dev);
280 extern int audit_dupe_exe(struct audit_krule *new, struct audit_krule *old);
281 extern int audit_exe_compare(struct task_struct *tsk, struct audit_fsnotify_mark *mark);
282 
283 #else
284 #define audit_put_watch(w) {}
285 #define audit_get_watch(w) {}
286 #define audit_to_watch(k, p, l, o) (-EINVAL)
287 #define audit_add_watch(k, l) (-EINVAL)
288 #define audit_remove_watch_rule(k) BUG()
289 #define audit_watch_path(w) ""
290 #define audit_watch_compare(w, i, d) 0
291 
292 #define audit_alloc_mark(k, p, l) (ERR_PTR(-EINVAL))
293 #define audit_mark_path(m) ""
294 #define audit_remove_mark(m)
295 #define audit_remove_mark_rule(k)
296 #define audit_mark_compare(m, i, d) 0
297 #define audit_exe_compare(t, m) (-EINVAL)
298 #define audit_dupe_exe(n, o) (-EINVAL)
299 #endif /* CONFIG_AUDIT_WATCH */
300 
301 #ifdef CONFIG_AUDIT_TREE
302 extern struct audit_chunk *audit_tree_lookup(const struct inode *);
303 extern void audit_put_chunk(struct audit_chunk *);
304 extern int audit_tree_match(struct audit_chunk *, struct audit_tree *);
305 extern int audit_make_tree(struct audit_krule *, char *, u32);
306 extern int audit_add_tree_rule(struct audit_krule *);
307 extern int audit_remove_tree_rule(struct audit_krule *);
308 extern void audit_trim_trees(void);
309 extern int audit_tag_tree(char *old, char *new);
310 extern const char *audit_tree_path(struct audit_tree *);
311 extern void audit_put_tree(struct audit_tree *);
312 extern void audit_kill_trees(struct list_head *);
313 #else
314 #define audit_remove_tree_rule(rule) BUG()
315 #define audit_add_tree_rule(rule) -EINVAL
316 #define audit_make_tree(rule, str, op) -EINVAL
317 #define audit_trim_trees() (void)0
318 #define audit_put_tree(tree) (void)0
319 #define audit_tag_tree(old, new) -EINVAL
320 #define audit_tree_path(rule) ""	/* never called */
321 #define audit_kill_trees(list) BUG()
322 #endif
323 
324 extern char *audit_unpack_string(void **, size_t *, size_t);
325 
326 extern pid_t audit_sig_pid;
327 extern kuid_t audit_sig_uid;
328 extern u32 audit_sig_sid;
329 
330 #ifdef CONFIG_AUDITSYSCALL
331 extern int __audit_signal_info(int sig, struct task_struct *t);
332 static inline int audit_signal_info(int sig, struct task_struct *t)
333 {
334 	if (unlikely((audit_pid && t->tgid == audit_pid) ||
335 		     (audit_signals && !audit_dummy_context())))
336 		return __audit_signal_info(sig, t);
337 	return 0;
338 }
339 extern void audit_filter_inodes(struct task_struct *, struct audit_context *);
340 extern struct list_head *audit_killed_trees(void);
341 #else
342 #define audit_signal_info(s,t) AUDIT_DISABLED
343 #define audit_filter_inodes(t,c) AUDIT_DISABLED
344 #endif
345 
346 extern struct mutex audit_cmd_mutex;
347