audit.h

  1/* SPDX-License-Identifier: GPL-2.0-or-later */
  2/* audit -- definition of audit_context structure and supporting types
  3 *
  4 * Copyright 2003-2004 Red Hat, Inc.
  5 * Copyright 2005 Hewlett-Packard Development Company, L.P.
  6 * Copyright 2005 IBM Corporation
  7 */
  8
  9#ifndef _KERNEL_AUDIT_H_
 10#define _KERNEL_AUDIT_H_
 11
 12#include <linux/fs.h>
 13#include <linux/audit.h>
 14#include <linux/security.h>
 15#include <linux/skbuff.h>
 16#include <uapi/linux/mqueue.h>
 17#include <linux/tty.h>
 18#include <uapi/linux/openat2.h> // struct open_how
 19
 20/* AUDIT_NAMES is the number of slots we reserve in the audit_context
 21 * for saving names from getname().  If we get more names we will allocate
 22 * a name dynamically and also add those to the list anchored by names_list. */
 23#define AUDIT_NAMES	5
 24
 25/* At task start time, the audit_state is set in the audit_context using
 26   a per-task filter.  At syscall entry, the audit_state is augmented by
 27   the syscall filter. */
 28enum audit_state {
 29	AUDIT_STATE_DISABLED,	/* Do not create per-task audit_context.
 30				 * No syscall-specific audit records can
 31				 * be generated. */
 32	AUDIT_STATE_BUILD,	/* Create the per-task audit_context,
 33				 * and fill it in at syscall
 34				 * entry time.  This makes a full
 35				 * syscall record available if some
 36				 * other part of the kernel decides it
 37				 * should be recorded. */
 38	AUDIT_STATE_RECORD	/* Create the per-task audit_context,
 39				 * always fill it in at syscall entry
 40				 * time, and always write out the audit
 41				 * record at syscall exit time.  */
 42};
 43
 44/* Rule lists */
 45struct audit_watch;
 46struct audit_fsnotify_mark;
 47struct audit_tree;
 48struct audit_chunk;
 49
 50struct audit_entry {
 51	struct list_head	list;
 52	struct rcu_head		rcu;
 53	struct audit_krule	rule;
 54};
 55
 56struct audit_cap_data {
 57	kernel_cap_t		permitted;
 58	kernel_cap_t		inheritable;
 59	union {
 60		unsigned int	fE;		/* effective bit of file cap */
 61		kernel_cap_t	effective;	/* effective set of process */
 62	};
 63	kernel_cap_t		ambient;
 64	kuid_t			rootid;
 65};
 66
 67/* When fs/namei.c:getname() is called, we store the pointer in name and bump
 68 * the refcnt in the associated filename struct.
 69 *
 70 * Further, in fs/namei.c:path_lookup() we store the inode and device.
 71 */
 72struct audit_names {
 73	struct list_head	list;		/* audit_context->names_list */
 74
 75	struct filename		*name;
 76	int			name_len;	/* number of chars to log */
 77	bool			hidden;		/* don't log this record */
 78
 79	unsigned long		ino;
 80	dev_t			dev;
 81	umode_t			mode;
 82	kuid_t			uid;
 83	kgid_t			gid;
 84	dev_t			rdev;
 85	struct lsm_prop		oprop;
 86	struct audit_cap_data	fcap;
 87	unsigned int		fcap_ver;
 88	unsigned char		type;		/* record type */
 89	/*
 90	 * This was an allocated audit_names and not from the array of
 91	 * names allocated in the task audit context.  Thus this name
 92	 * should be freed on syscall exit.
 93	 */
 94	bool			should_free;
 95};
 96
 97struct audit_proctitle {
 98	int	len;	/* length of the cmdline field. */
 99	char	*value;	/* the cmdline field */
100};
101
102/* A timestamp/serial pair to identify an event */
103struct audit_stamp {
104	struct timespec64	ctime;	/* time of syscall entry */
105	unsigned int		serial;	/* serial number for record */
106};
107
108/* The per-task audit context. */
109struct audit_context {
110	int		    dummy;	/* must be the first element */
111	enum {
112		AUDIT_CTX_UNUSED,	/* audit_context is currently unused */
113		AUDIT_CTX_SYSCALL,	/* in use by syscall */
114		AUDIT_CTX_URING,	/* in use by io_uring */
115	} context;
116	enum audit_state    state, current_state;
117	struct audit_stamp  stamp;	/* event identifier */
118	int		    major;      /* syscall number */
119	int		    uring_op;   /* uring operation */
120	unsigned long	    argv[4];    /* syscall arguments */
121	long		    return_code;/* syscall return code */
122	u64		    prio;
123	int		    return_valid; /* return code is valid */
124	/*
125	 * The names_list is the list of all audit_names collected during this
126	 * syscall.  The first AUDIT_NAMES entries in the names_list will
127	 * actually be from the preallocated_names array for performance
128	 * reasons.  Except during allocation they should never be referenced
129	 * through the preallocated_names array and should only be found/used
130	 * by running the names_list.
131	 */
132	struct audit_names  preallocated_names[AUDIT_NAMES];
133	int		    name_count; /* total records in names_list */
134	struct list_head    names_list;	/* struct audit_names->list anchor */
135	char		    *filterkey;	/* key for rule that triggered record */
136	struct path	    pwd;
137	struct audit_aux_data *aux;
138	struct audit_aux_data *aux_pids;
139	struct sockaddr_storage *sockaddr;
140	size_t sockaddr_len;
141	/* Save things to print about task_struct */
142	pid_t		    ppid;
143	kuid_t		    uid, euid, suid, fsuid;
144	kgid_t		    gid, egid, sgid, fsgid;
145	unsigned long	    personality;
146	int		    arch;
147
148	pid_t		    target_pid;
149	kuid_t		    target_auid;
150	kuid_t		    target_uid;
151	unsigned int	    target_sessionid;
152	struct lsm_prop	    target_ref;
153	char		    target_comm[TASK_COMM_LEN];
154
155	struct audit_tree_refs *trees, *first_trees;
156	struct list_head killed_trees;
157	int tree_count;
158
159	int type;
160	union {
161		struct {
162			int nargs;
163			long args[6];
164		} socketcall;
165		struct {
166			kuid_t			uid;
167			kgid_t			gid;
168			umode_t			mode;
169			struct lsm_prop		oprop;
170			int			has_perm;
171			uid_t			perm_uid;
172			gid_t			perm_gid;
173			umode_t			perm_mode;
174			unsigned long		qbytes;
175		} ipc;
176		struct {
177			mqd_t			mqdes;
178			struct mq_attr		mqstat;
179		} mq_getsetattr;
180		struct {
181			mqd_t			mqdes;
182			int			sigev_signo;
183		} mq_notify;
184		struct {
185			mqd_t			mqdes;
186			size_t			msg_len;
187			unsigned int		msg_prio;
188			struct timespec64	abs_timeout;
189		} mq_sendrecv;
190		struct {
191			int			oflag;
192			umode_t			mode;
193			struct mq_attr		attr;
194		} mq_open;
195		struct {
196			pid_t			pid;
197			struct audit_cap_data	cap;
198		} capset;
199		struct {
200			int			fd;
201			int			flags;
202		} mmap;
203		struct open_how openat2;
204		struct {
205			int			argc;
206		} execve;
207		struct {
208			const char		*name;
209		} module;
210		struct {
211			struct audit_ntp_data	ntp_data;
212			struct timespec64	tk_injoffset;
213		} time;
214	};
215	int fds[2];
216	struct audit_proctitle proctitle;
217};
218
219extern bool audit_ever_enabled;
220
221extern void audit_log_session_info(struct audit_buffer *ab);
222
223extern int auditd_test_task(struct task_struct *task);
224
225#define AUDIT_INODE_BUCKETS	32
226extern struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS];
227
228static inline int audit_hash_ino(u32 ino)
229{
230	return (ino & (AUDIT_INODE_BUCKETS-1));
231}
232
233/* Indicates that audit should log the full pathname. */
234#define AUDIT_NAME_FULL -1
235
236extern int audit_match_class(int class, unsigned syscall);
237extern int audit_comparator(const u32 left, const u32 op, const u32 right);
238extern int audit_uid_comparator(kuid_t left, u32 op, kuid_t right);
239extern int audit_gid_comparator(kgid_t left, u32 op, kgid_t right);
240extern int parent_len(const char *path);
241extern int audit_compare_dname_path(const struct qstr *dname, const char *path, int plen);
242extern struct sk_buff *audit_make_reply(int seq, int type, int done, int multi,
243					const void *payload, int size);
244extern void		    audit_panic(const char *message);
245
246struct audit_netlink_list {
247	__u32 portid;
248	struct net *net;
249	struct sk_buff_head q;
250};
251
252int audit_send_list_thread(void *_dest);
253
254extern struct mutex audit_filter_mutex;
255extern int audit_del_rule(struct audit_entry *entry);
256extern void audit_free_rule_rcu(struct rcu_head *head);
257extern struct list_head audit_filter_list[];
258
259extern struct audit_entry *audit_dupe_rule(struct audit_krule *old);
260
261extern void audit_log_d_path_exe(struct audit_buffer *ab,
262				 struct mm_struct *mm);
263
264extern struct tty_struct *audit_get_tty(void);
265extern void audit_put_tty(struct tty_struct *tty);
266
267/* audit watch/mark/tree functions */
268extern unsigned int audit_serial(void);
269#ifdef CONFIG_AUDITSYSCALL
270extern int auditsc_get_stamp(struct audit_context *ctx,
271			     struct audit_stamp *stamp);
272
273extern void audit_put_watch(struct audit_watch *watch);
274extern void audit_get_watch(struct audit_watch *watch);
275extern int audit_to_watch(struct audit_krule *krule, char *path, int len,
276			  u32 op);
277extern int audit_add_watch(struct audit_krule *krule, struct list_head **list);
278extern void audit_remove_watch_rule(struct audit_krule *krule);
279extern char *audit_watch_path(struct audit_watch *watch);
280extern int audit_watch_compare(struct audit_watch *watch, unsigned long ino,
281			       dev_t dev);
282
283extern struct audit_fsnotify_mark *audit_alloc_mark(struct audit_krule *krule,
284						    char *pathname, int len);
285extern char *audit_mark_path(struct audit_fsnotify_mark *mark);
286extern void audit_remove_mark(struct audit_fsnotify_mark *audit_mark);
287extern void audit_remove_mark_rule(struct audit_krule *krule);
288extern int audit_mark_compare(struct audit_fsnotify_mark *mark,
289			      unsigned long ino, dev_t dev);
290extern int audit_dupe_exe(struct audit_krule *new, struct audit_krule *old);
291extern int audit_exe_compare(struct task_struct *tsk,
292			     struct audit_fsnotify_mark *mark);
293
294extern struct audit_chunk *audit_tree_lookup(const struct inode *inode);
295extern void audit_put_chunk(struct audit_chunk *chunk);
296extern bool audit_tree_match(struct audit_chunk *chunk,
297			     struct audit_tree *tree);
298extern int audit_make_tree(struct audit_krule *rule, char *pathname, u32 op);
299extern int audit_add_tree_rule(struct audit_krule *rule);
300extern int audit_remove_tree_rule(struct audit_krule *rule);
301extern void audit_trim_trees(void);
302extern int audit_tag_tree(char *old, char *new);
303extern const char *audit_tree_path(struct audit_tree *tree);
304extern void audit_put_tree(struct audit_tree *tree);
305extern void audit_kill_trees(struct audit_context *context);
306
307extern int audit_signal_info_syscall(struct task_struct *t);
308extern void audit_filter_inodes(struct task_struct *tsk,
309				struct audit_context *ctx);
310extern struct list_head *audit_killed_trees(void);
311#else /* CONFIG_AUDITSYSCALL */
312#define auditsc_get_stamp(c, s) 0
313#define audit_put_watch(w) do { } while (0)
314#define audit_get_watch(w) do { } while (0)
315#define audit_to_watch(k, p, l, o) (-EINVAL)
316#define audit_add_watch(k, l) (-EINVAL)
317#define audit_remove_watch_rule(k) BUG()
318#define audit_watch_path(w) ""
319#define audit_watch_compare(w, i, d) 0
320
321#define audit_alloc_mark(k, p, l) (ERR_PTR(-EINVAL))
322#define audit_mark_path(m) ""
323#define audit_remove_mark(m) do { } while (0)
324#define audit_remove_mark_rule(k) do { } while (0)
325#define audit_mark_compare(m, i, d) 0
326#define audit_exe_compare(t, m) (-EINVAL)
327#define audit_dupe_exe(n, o) (-EINVAL)
328
329#define audit_remove_tree_rule(rule) BUG()
330#define audit_add_tree_rule(rule) -EINVAL
331#define audit_make_tree(rule, str, op) -EINVAL
332#define audit_trim_trees() do { } while (0)
333#define audit_put_tree(tree) do { } while (0)
334#define audit_tag_tree(old, new) -EINVAL
335#define audit_tree_path(rule) ""	/* never called */
336#define audit_kill_trees(context) BUG()
337
338static inline int audit_signal_info_syscall(struct task_struct *t)
339{
340	return 0;
341}
342
343#define audit_filter_inodes(t, c) do { } while (0)
344#endif /* CONFIG_AUDITSYSCALL */
345
346extern char *audit_unpack_string(void **bufp, size_t *remain, size_t len);
347
348extern int audit_filter(int msgtype, unsigned int listtype);
349
350extern void audit_ctl_lock(void);
351extern void audit_ctl_unlock(void);
352
353#endif