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