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