xref: /linux/kernel/audit.h (revision 9a379e77033f02c4a071891afdf0f0a01eff8ccb)
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 #include <linux/tty.h>
27 
28 /* AUDIT_NAMES is the number of slots we reserve in the audit_context
29  * for saving names from getname().  If we get more names we will allocate
30  * a name dynamically and also add those to the list anchored by names_list. */
31 #define AUDIT_NAMES	5
32 
33 /* At task start time, the audit_state is set in the audit_context using
34    a per-task filter.  At syscall entry, the audit_state is augmented by
35    the syscall filter. */
36 enum audit_state {
37 	AUDIT_DISABLED,		/* Do not create per-task audit_context.
38 				 * No syscall-specific audit records can
39 				 * be generated. */
40 	AUDIT_BUILD_CONTEXT,	/* Create the per-task audit_context,
41 				 * and fill it in at syscall
42 				 * entry time.  This makes a full
43 				 * syscall record available if some
44 				 * other part of the kernel decides it
45 				 * should be recorded. */
46 	AUDIT_RECORD_CONTEXT	/* Create the per-task audit_context,
47 				 * always fill it in at syscall entry
48 				 * time, and always write out the audit
49 				 * record at syscall exit time.  */
50 };
51 
52 /* Rule lists */
53 struct audit_watch;
54 struct audit_fsnotify_mark;
55 struct audit_tree;
56 struct audit_chunk;
57 
58 struct audit_entry {
59 	struct list_head	list;
60 	struct rcu_head		rcu;
61 	struct audit_krule	rule;
62 };
63 
64 struct audit_cap_data {
65 	kernel_cap_t		permitted;
66 	kernel_cap_t		inheritable;
67 	union {
68 		unsigned int	fE;		/* effective bit of file cap */
69 		kernel_cap_t	effective;	/* effective set of process */
70 	};
71 	kernel_cap_t		ambient;
72 };
73 
74 /* When fs/namei.c:getname() is called, we store the pointer in name and bump
75  * the refcnt in the associated filename struct.
76  *
77  * Further, in fs/namei.c:path_lookup() we store the inode and device.
78  */
79 struct audit_names {
80 	struct list_head	list;		/* audit_context->names_list */
81 
82 	struct filename		*name;
83 	int			name_len;	/* number of chars to log */
84 	bool			hidden;		/* don't log this record */
85 
86 	unsigned long		ino;
87 	dev_t			dev;
88 	umode_t			mode;
89 	kuid_t			uid;
90 	kgid_t			gid;
91 	dev_t			rdev;
92 	u32			osid;
93 	struct audit_cap_data	fcap;
94 	unsigned int		fcap_ver;
95 	unsigned char		type;		/* record type */
96 	/*
97 	 * This was an allocated audit_names and not from the array of
98 	 * names allocated in the task audit context.  Thus this name
99 	 * should be freed on syscall exit.
100 	 */
101 	bool			should_free;
102 };
103 
104 struct audit_proctitle {
105 	int	len;	/* length of the cmdline field. */
106 	char	*value;	/* the cmdline field */
107 };
108 
109 /* The per-task audit context. */
110 struct audit_context {
111 	int		    dummy;	/* must be the first element */
112 	int		    in_syscall;	/* 1 if task is in a syscall */
113 	enum audit_state    state, current_state;
114 	unsigned int	    serial;     /* serial number for record */
115 	int		    major;      /* syscall number */
116 	struct timespec64   ctime;      /* time of syscall entry */
117 	unsigned long	    argv[4];    /* syscall arguments */
118 	long		    return_code;/* syscall return code */
119 	u64		    prio;
120 	int		    return_valid; /* return code is valid */
121 	/*
122 	 * The names_list is the list of all audit_names collected during this
123 	 * syscall.  The first AUDIT_NAMES entries in the names_list will
124 	 * actually be from the preallocated_names array for performance
125 	 * reasons.  Except during allocation they should never be referenced
126 	 * through the preallocated_names array and should only be found/used
127 	 * by running the names_list.
128 	 */
129 	struct audit_names  preallocated_names[AUDIT_NAMES];
130 	int		    name_count; /* total records in names_list */
131 	struct list_head    names_list;	/* struct audit_names->list anchor */
132 	char		    *filterkey;	/* key for rule that triggered record */
133 	struct path	    pwd;
134 	struct audit_aux_data *aux;
135 	struct audit_aux_data *aux_pids;
136 	struct sockaddr_storage *sockaddr;
137 	size_t sockaddr_len;
138 				/* Save things to print about task_struct */
139 	pid_t		    pid, ppid;
140 	kuid_t		    uid, euid, suid, fsuid;
141 	kgid_t		    gid, egid, sgid, fsgid;
142 	unsigned long	    personality;
143 	int		    arch;
144 
145 	pid_t		    target_pid;
146 	kuid_t		    target_auid;
147 	kuid_t		    target_uid;
148 	unsigned int	    target_sessionid;
149 	u32		    target_sid;
150 	char		    target_comm[TASK_COMM_LEN];
151 
152 	struct audit_tree_refs *trees, *first_trees;
153 	struct list_head killed_trees;
154 	int tree_count;
155 
156 	int type;
157 	union {
158 		struct {
159 			int nargs;
160 			long args[6];
161 		} socketcall;
162 		struct {
163 			kuid_t			uid;
164 			kgid_t			gid;
165 			umode_t			mode;
166 			u32			osid;
167 			int			has_perm;
168 			uid_t			perm_uid;
169 			gid_t			perm_gid;
170 			umode_t			perm_mode;
171 			unsigned long		qbytes;
172 		} ipc;
173 		struct {
174 			mqd_t			mqdes;
175 			struct mq_attr		mqstat;
176 		} mq_getsetattr;
177 		struct {
178 			mqd_t			mqdes;
179 			int			sigev_signo;
180 		} mq_notify;
181 		struct {
182 			mqd_t			mqdes;
183 			size_t			msg_len;
184 			unsigned int		msg_prio;
185 			struct timespec64	abs_timeout;
186 		} mq_sendrecv;
187 		struct {
188 			int			oflag;
189 			umode_t			mode;
190 			struct mq_attr		attr;
191 		} mq_open;
192 		struct {
193 			pid_t			pid;
194 			struct audit_cap_data	cap;
195 		} capset;
196 		struct {
197 			int			fd;
198 			int			flags;
199 		} mmap;
200 		struct {
201 			int			argc;
202 		} execve;
203 		struct {
204 			char			*name;
205 		} module;
206 	};
207 	int fds[2];
208 	struct audit_proctitle proctitle;
209 };
210 
211 extern bool audit_ever_enabled;
212 
213 extern void audit_copy_inode(struct audit_names *name,
214 			     const struct dentry *dentry,
215 			     struct inode *inode);
216 extern void audit_log_cap(struct audit_buffer *ab, char *prefix,
217 			  kernel_cap_t *cap);
218 extern void audit_log_name(struct audit_context *context,
219 			   struct audit_names *n, const struct path *path,
220 			   int record_num, int *call_panic);
221 
222 extern int auditd_test_task(struct task_struct *task);
223 
224 #define AUDIT_INODE_BUCKETS	32
225 extern struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS];
226 
227 static inline int audit_hash_ino(u32 ino)
228 {
229 	return (ino & (AUDIT_INODE_BUCKETS-1));
230 }
231 
232 /* Indicates that audit should log the full pathname. */
233 #define AUDIT_NAME_FULL -1
234 
235 extern int audit_match_class(int class, unsigned syscall);
236 extern int audit_comparator(const u32 left, const u32 op, const u32 right);
237 extern int audit_uid_comparator(kuid_t left, u32 op, kuid_t right);
238 extern int audit_gid_comparator(kgid_t left, u32 op, kgid_t right);
239 extern int parent_len(const char *path);
240 extern int audit_compare_dname_path(const char *dname, const char *path, int plen);
241 extern struct sk_buff *audit_make_reply(int seq, int type, int done, int multi,
242 					const void *payload, int size);
243 extern void		    audit_panic(const char *message);
244 
245 struct audit_netlink_list {
246 	__u32 portid;
247 	struct net *net;
248 	struct sk_buff_head q;
249 };
250 
251 int audit_send_list(void *_dest);
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 *entry);
257 extern void audit_free_rule_rcu(struct rcu_head *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 extern struct tty_struct *audit_get_tty(struct task_struct *tsk);
266 extern void audit_put_tty(struct tty_struct *tty);
267 
268 /* audit watch functions */
269 #ifdef CONFIG_AUDIT_WATCH
270 extern void audit_put_watch(struct audit_watch *watch);
271 extern void audit_get_watch(struct audit_watch *watch);
272 extern int audit_to_watch(struct audit_krule *krule, char *path, int len, u32 op);
273 extern int audit_add_watch(struct audit_krule *krule, struct list_head **list);
274 extern void audit_remove_watch_rule(struct audit_krule *krule);
275 extern char *audit_watch_path(struct audit_watch *watch);
276 extern int audit_watch_compare(struct audit_watch *watch, unsigned long ino, dev_t dev);
277 
278 extern struct audit_fsnotify_mark *audit_alloc_mark(struct audit_krule *krule, char *pathname, int len);
279 extern char *audit_mark_path(struct audit_fsnotify_mark *mark);
280 extern void audit_remove_mark(struct audit_fsnotify_mark *audit_mark);
281 extern void audit_remove_mark_rule(struct audit_krule *krule);
282 extern int audit_mark_compare(struct audit_fsnotify_mark *mark, unsigned long ino, dev_t dev);
283 extern int audit_dupe_exe(struct audit_krule *new, struct audit_krule *old);
284 extern int audit_exe_compare(struct task_struct *tsk, struct audit_fsnotify_mark *mark);
285 
286 #else
287 #define audit_put_watch(w) {}
288 #define audit_get_watch(w) {}
289 #define audit_to_watch(k, p, l, o) (-EINVAL)
290 #define audit_add_watch(k, l) (-EINVAL)
291 #define audit_remove_watch_rule(k) BUG()
292 #define audit_watch_path(w) ""
293 #define audit_watch_compare(w, i, d) 0
294 
295 #define audit_alloc_mark(k, p, l) (ERR_PTR(-EINVAL))
296 #define audit_mark_path(m) ""
297 #define audit_remove_mark(m)
298 #define audit_remove_mark_rule(k)
299 #define audit_mark_compare(m, i, d) 0
300 #define audit_exe_compare(t, m) (-EINVAL)
301 #define audit_dupe_exe(n, o) (-EINVAL)
302 #endif /* CONFIG_AUDIT_WATCH */
303 
304 #ifdef CONFIG_AUDIT_TREE
305 extern struct audit_chunk *audit_tree_lookup(const struct inode *inode);
306 extern void audit_put_chunk(struct audit_chunk *chunk);
307 extern bool audit_tree_match(struct audit_chunk *chunk, struct audit_tree *tree);
308 extern int audit_make_tree(struct audit_krule *rule, char *pathname, u32 op);
309 extern int audit_add_tree_rule(struct audit_krule *rule);
310 extern int audit_remove_tree_rule(struct audit_krule *rule);
311 extern void audit_trim_trees(void);
312 extern int audit_tag_tree(char *old, char *new);
313 extern const char *audit_tree_path(struct audit_tree *tree);
314 extern void audit_put_tree(struct audit_tree *tree);
315 extern void audit_kill_trees(struct list_head *list);
316 #else
317 #define audit_remove_tree_rule(rule) BUG()
318 #define audit_add_tree_rule(rule) -EINVAL
319 #define audit_make_tree(rule, str, op) -EINVAL
320 #define audit_trim_trees() (void)0
321 #define audit_put_tree(tree) (void)0
322 #define audit_tag_tree(old, new) -EINVAL
323 #define audit_tree_path(rule) ""	/* never called */
324 #define audit_kill_trees(list) BUG()
325 #endif
326 
327 extern char *audit_unpack_string(void **bufp, size_t *remain, size_t len);
328 
329 extern pid_t audit_sig_pid;
330 extern kuid_t audit_sig_uid;
331 extern u32 audit_sig_sid;
332 
333 extern int audit_filter(int msgtype, unsigned int listtype);
334 
335 #ifdef CONFIG_AUDITSYSCALL
336 extern int audit_signal_info(int sig, struct task_struct *t);
337 extern void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx);
338 extern struct list_head *audit_killed_trees(void);
339 #else
340 #define audit_signal_info(s,t) AUDIT_DISABLED
341 #define audit_filter_inodes(t,c) AUDIT_DISABLED
342 #endif
343 
344 extern struct mutex audit_cmd_mutex;
345