xref: /openbmc/linux/kernel/audit.h (revision cb1aaebe)
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 	kuid_t			rootid;
73 };
74 
75 /* When fs/namei.c:getname() is called, we store the pointer in name and bump
76  * the refcnt in the associated filename struct.
77  *
78  * Further, in fs/namei.c:path_lookup() we store the inode and device.
79  */
80 struct audit_names {
81 	struct list_head	list;		/* audit_context->names_list */
82 
83 	struct filename		*name;
84 	int			name_len;	/* number of chars to log */
85 	bool			hidden;		/* don't log this record */
86 
87 	unsigned long		ino;
88 	dev_t			dev;
89 	umode_t			mode;
90 	kuid_t			uid;
91 	kgid_t			gid;
92 	dev_t			rdev;
93 	u32			osid;
94 	struct audit_cap_data	fcap;
95 	unsigned int		fcap_ver;
96 	unsigned char		type;		/* record type */
97 	/*
98 	 * This was an allocated audit_names and not from the array of
99 	 * names allocated in the task audit context.  Thus this name
100 	 * should be freed on syscall exit.
101 	 */
102 	bool			should_free;
103 };
104 
105 struct audit_proctitle {
106 	int	len;	/* length of the cmdline field. */
107 	char	*value;	/* the cmdline field */
108 };
109 
110 /* The per-task audit context. */
111 struct audit_context {
112 	int		    dummy;	/* must be the first element */
113 	int		    in_syscall;	/* 1 if task is in a syscall */
114 	enum audit_state    state, current_state;
115 	unsigned int	    serial;     /* serial number for record */
116 	int		    major;      /* syscall number */
117 	struct timespec64   ctime;      /* time of syscall entry */
118 	unsigned long	    argv[4];    /* syscall arguments */
119 	long		    return_code;/* syscall return code */
120 	u64		    prio;
121 	int		    return_valid; /* return code is valid */
122 	/*
123 	 * The names_list is the list of all audit_names collected during this
124 	 * syscall.  The first AUDIT_NAMES entries in the names_list will
125 	 * actually be from the preallocated_names array for performance
126 	 * reasons.  Except during allocation they should never be referenced
127 	 * through the preallocated_names array and should only be found/used
128 	 * by running the names_list.
129 	 */
130 	struct audit_names  preallocated_names[AUDIT_NAMES];
131 	int		    name_count; /* total records in names_list */
132 	struct list_head    names_list;	/* struct audit_names->list anchor */
133 	char		    *filterkey;	/* key for rule that triggered record */
134 	struct path	    pwd;
135 	struct audit_aux_data *aux;
136 	struct audit_aux_data *aux_pids;
137 	struct sockaddr_storage *sockaddr;
138 	size_t sockaddr_len;
139 				/* Save things to print about task_struct */
140 	pid_t		    pid, ppid;
141 	kuid_t		    uid, euid, suid, fsuid;
142 	kgid_t		    gid, egid, sgid, fsgid;
143 	unsigned long	    personality;
144 	int		    arch;
145 
146 	pid_t		    target_pid;
147 	kuid_t		    target_auid;
148 	kuid_t		    target_uid;
149 	unsigned int	    target_sessionid;
150 	u32		    target_sid;
151 	char		    target_comm[TASK_COMM_LEN];
152 
153 	struct audit_tree_refs *trees, *first_trees;
154 	struct list_head killed_trees;
155 	int tree_count;
156 
157 	int type;
158 	union {
159 		struct {
160 			int nargs;
161 			long args[6];
162 		} socketcall;
163 		struct {
164 			kuid_t			uid;
165 			kgid_t			gid;
166 			umode_t			mode;
167 			u32			osid;
168 			int			has_perm;
169 			uid_t			perm_uid;
170 			gid_t			perm_gid;
171 			umode_t			perm_mode;
172 			unsigned long		qbytes;
173 		} ipc;
174 		struct {
175 			mqd_t			mqdes;
176 			struct mq_attr		mqstat;
177 		} mq_getsetattr;
178 		struct {
179 			mqd_t			mqdes;
180 			int			sigev_signo;
181 		} mq_notify;
182 		struct {
183 			mqd_t			mqdes;
184 			size_t			msg_len;
185 			unsigned int		msg_prio;
186 			struct timespec64	abs_timeout;
187 		} mq_sendrecv;
188 		struct {
189 			int			oflag;
190 			umode_t			mode;
191 			struct mq_attr		attr;
192 		} mq_open;
193 		struct {
194 			pid_t			pid;
195 			struct audit_cap_data	cap;
196 		} capset;
197 		struct {
198 			int			fd;
199 			int			flags;
200 		} mmap;
201 		struct {
202 			int			argc;
203 		} execve;
204 		struct {
205 			char			*name;
206 		} module;
207 	};
208 	int fds[2];
209 	struct audit_proctitle proctitle;
210 };
211 
212 extern bool audit_ever_enabled;
213 
214 extern void audit_log_session_info(struct audit_buffer *ab);
215 
216 extern int auditd_test_task(struct task_struct *task);
217 
218 #define AUDIT_INODE_BUCKETS	32
219 extern struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS];
220 
221 static inline int audit_hash_ino(u32 ino)
222 {
223 	return (ino & (AUDIT_INODE_BUCKETS-1));
224 }
225 
226 /* Indicates that audit should log the full pathname. */
227 #define AUDIT_NAME_FULL -1
228 
229 extern int audit_match_class(int class, unsigned syscall);
230 extern int audit_comparator(const u32 left, const u32 op, const u32 right);
231 extern int audit_uid_comparator(kuid_t left, u32 op, kuid_t right);
232 extern int audit_gid_comparator(kgid_t left, u32 op, kgid_t right);
233 extern int parent_len(const char *path);
234 extern int audit_compare_dname_path(const struct qstr *dname, const char *path, int plen);
235 extern struct sk_buff *audit_make_reply(int seq, int type, int done, int multi,
236 					const void *payload, int size);
237 extern void		    audit_panic(const char *message);
238 
239 struct audit_netlink_list {
240 	__u32 portid;
241 	struct net *net;
242 	struct sk_buff_head q;
243 };
244 
245 int audit_send_list(void *_dest);
246 
247 extern int selinux_audit_rule_update(void);
248 
249 extern struct mutex audit_filter_mutex;
250 extern int audit_del_rule(struct audit_entry *entry);
251 extern void audit_free_rule_rcu(struct rcu_head *head);
252 extern struct list_head audit_filter_list[];
253 
254 extern struct audit_entry *audit_dupe_rule(struct audit_krule *old);
255 
256 extern void audit_log_d_path_exe(struct audit_buffer *ab,
257 				 struct mm_struct *mm);
258 
259 extern struct tty_struct *audit_get_tty(void);
260 extern void audit_put_tty(struct tty_struct *tty);
261 
262 /* audit watch/mark/tree functions */
263 #ifdef CONFIG_AUDITSYSCALL
264 extern unsigned int audit_serial(void);
265 extern int auditsc_get_stamp(struct audit_context *ctx,
266 			      struct timespec64 *t, unsigned int *serial);
267 
268 extern void audit_put_watch(struct audit_watch *watch);
269 extern void audit_get_watch(struct audit_watch *watch);
270 extern int audit_to_watch(struct audit_krule *krule, char *path, int len,
271 			  u32 op);
272 extern int audit_add_watch(struct audit_krule *krule, struct list_head **list);
273 extern void audit_remove_watch_rule(struct audit_krule *krule);
274 extern char *audit_watch_path(struct audit_watch *watch);
275 extern int audit_watch_compare(struct audit_watch *watch, unsigned long ino,
276 			       dev_t dev);
277 
278 extern struct audit_fsnotify_mark *audit_alloc_mark(struct audit_krule *krule,
279 						    char *pathname, int len);
280 extern char *audit_mark_path(struct audit_fsnotify_mark *mark);
281 extern void audit_remove_mark(struct audit_fsnotify_mark *audit_mark);
282 extern void audit_remove_mark_rule(struct audit_krule *krule);
283 extern int audit_mark_compare(struct audit_fsnotify_mark *mark,
284 			      unsigned long ino, dev_t dev);
285 extern int audit_dupe_exe(struct audit_krule *new, struct audit_krule *old);
286 extern int audit_exe_compare(struct task_struct *tsk,
287 			     struct audit_fsnotify_mark *mark);
288 
289 extern struct audit_chunk *audit_tree_lookup(const struct inode *inode);
290 extern void audit_put_chunk(struct audit_chunk *chunk);
291 extern bool audit_tree_match(struct audit_chunk *chunk,
292 			     struct audit_tree *tree);
293 extern int audit_make_tree(struct audit_krule *rule, char *pathname, u32 op);
294 extern int audit_add_tree_rule(struct audit_krule *rule);
295 extern int audit_remove_tree_rule(struct audit_krule *rule);
296 extern void audit_trim_trees(void);
297 extern int audit_tag_tree(char *old, char *new);
298 extern const char *audit_tree_path(struct audit_tree *tree);
299 extern void audit_put_tree(struct audit_tree *tree);
300 extern void audit_kill_trees(struct audit_context *context);
301 
302 extern int audit_signal_info(int sig, struct task_struct *t);
303 extern void audit_filter_inodes(struct task_struct *tsk,
304 				struct audit_context *ctx);
305 extern struct list_head *audit_killed_trees(void);
306 #else /* CONFIG_AUDITSYSCALL */
307 #define auditsc_get_stamp(c, t, s) 0
308 #define audit_put_watch(w) {}
309 #define audit_get_watch(w) {}
310 #define audit_to_watch(k, p, l, o) (-EINVAL)
311 #define audit_add_watch(k, l) (-EINVAL)
312 #define audit_remove_watch_rule(k) BUG()
313 #define audit_watch_path(w) ""
314 #define audit_watch_compare(w, i, d) 0
315 
316 #define audit_alloc_mark(k, p, l) (ERR_PTR(-EINVAL))
317 #define audit_mark_path(m) ""
318 #define audit_remove_mark(m)
319 #define audit_remove_mark_rule(k)
320 #define audit_mark_compare(m, i, d) 0
321 #define audit_exe_compare(t, m) (-EINVAL)
322 #define audit_dupe_exe(n, o) (-EINVAL)
323 
324 #define audit_remove_tree_rule(rule) BUG()
325 #define audit_add_tree_rule(rule) -EINVAL
326 #define audit_make_tree(rule, str, op) -EINVAL
327 #define audit_trim_trees() (void)0
328 #define audit_put_tree(tree) (void)0
329 #define audit_tag_tree(old, new) -EINVAL
330 #define audit_tree_path(rule) ""	/* never called */
331 #define audit_kill_trees(context) BUG()
332 
333 #define audit_signal_info(s, t) AUDIT_DISABLED
334 #define audit_filter_inodes(t, c) AUDIT_DISABLED
335 #endif /* CONFIG_AUDITSYSCALL */
336 
337 extern char *audit_unpack_string(void **bufp, size_t *remain, size_t len);
338 
339 extern pid_t audit_sig_pid;
340 extern kuid_t audit_sig_uid;
341 extern u32 audit_sig_sid;
342 
343 extern int audit_filter(int msgtype, unsigned int listtype);
344 
345 extern void audit_ctl_lock(void);
346 extern void audit_ctl_unlock(void);
347