kernel/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. */
  28 enum 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 */
  45 struct audit_watch;
  46 struct audit_fsnotify_mark;
  47 struct audit_tree;
  48 struct audit_chunk;
  49
  50 struct audit_entry {
  51         struct list_head        list;
  52         struct rcu_head         rcu;
  53         struct audit_krule      rule;
  54 };
  55
  56 struct 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  */
  72 struct 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
  97 struct audit_proctitle {
  98         int     len;    /* length of the cmdline field. */
  99         char    *value; /* the cmdline field */
 100 };
 101
 102 /* The per-task audit context. */
 103 struct audit_context {
 104         int                 dummy;      /* must be the first element */
 105         enum {
 106                 AUDIT_CTX_UNUSED,       /* audit_context is currently unused */
 107                 AUDIT_CTX_SYSCALL,      /* in use by syscall */
 108                 AUDIT_CTX_URING,        /* in use by io_uring */
 109         } context;
 110         enum audit_state    state, current_state;
 111         unsigned int        serial;     /* serial number for record */
 112         int                 major;      /* syscall number */
 113         int                 uring_op;   /* uring operation */
 114         struct timespec64   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               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         struct lsm_prop     target_ref;
 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                         struct lsm_prop         oprop;
 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 timespec64       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 open_how openat2;
 199                 struct {
 200                         int                     argc;
 201                 } execve;
 202                 struct {
 203                         char                    *name;
 204                 } module;
 205                 struct {
 206                         struct audit_ntp_data   ntp_data;
 207                         struct timespec64       tk_injoffset;
 208                 } time;
 209         };
 210         int fds[2];
 211         struct audit_proctitle proctitle;
 212 };
 213
 214 extern bool audit_ever_enabled;
 215
 216 extern void audit_log_session_info(struct audit_buffer *ab);
 217
 218 extern int auditd_test_task(struct task_struct *task);
 219
 220 #define AUDIT_INODE_BUCKETS     32
 221 extern struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS];
 222
 223 static inline int audit_hash_ino(u32 ino)
 224 {
 225         return (ino & (AUDIT_INODE_BUCKETS-1));
 226 }
 227
 228 /* Indicates that audit should log the full pathname. */
 229 #define AUDIT_NAME_FULL -1
 230
 231 extern int audit_match_class(int class, unsigned syscall);
 232 extern int audit_comparator(const u32 left, const u32 op, const u32 right);
 233 extern int audit_uid_comparator(kuid_t left, u32 op, kuid_t right);
 234 extern int audit_gid_comparator(kgid_t left, u32 op, kgid_t right);
 235 extern int parent_len(const char *path);
 236 extern int audit_compare_dname_path(const struct qstr *dname, const char *path, int plen);
 237 extern struct sk_buff *audit_make_reply(int seq, int type, 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_thread(void *_dest);
 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 extern unsigned int audit_serial(void);
 264 #ifdef CONFIG_AUDITSYSCALL
 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_syscall(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) do { } while (0)
 309 #define audit_get_watch(w) do { } while (0)
 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) do { } while (0)
 319 #define audit_remove_mark_rule(k) do { } while (0)
 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() do { } while (0)
 328 #define audit_put_tree(tree) do { } while (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 static inline int audit_signal_info_syscall(struct task_struct *t)
 334 {
 335         return 0;
 336 }
 337
 338 #define audit_filter_inodes(t, c) do { } while (0)
 339 #endif /* CONFIG_AUDITSYSCALL */
 340
 341 extern char *audit_unpack_string(void **bufp, size_t *remain, size_t len);
 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
 348 #endif