Line data    Source code

       1             : /* SPDX-License-Identifier: GPL-2.0 */
       2             : /*
       3             :   File: linux/posix_acl.h
       4             : 
       5             :   (C) 2002 Andreas Gruenbacher, <a.gruenbacher@computer.org>
       6             : */
       7             : 
       8             : 
       9             : #ifndef __LINUX_POSIX_ACL_H
      10             : #define __LINUX_POSIX_ACL_H
      11             : 
      12             : #include <linux/bug.h>
      13             : #include <linux/slab.h>
      14             : #include <linux/rcupdate.h>
      15             : #include <linux/refcount.h>
      16             : #include <uapi/linux/posix_acl.h>
      17             : 
      18             : struct user_namespace;
      19             : 
      20             : struct posix_acl_entry {
      21             :         short                   e_tag;
      22             :         unsigned short          e_perm;
      23             :         union {
      24             :                 kuid_t          e_uid;
      25             :                 kgid_t          e_gid;
      26             :         };
      27             : };
      28             : 
      29             : struct posix_acl {
      30             :         refcount_t              a_refcount;
      31             :         struct rcu_head         a_rcu;
      32             :         unsigned int            a_count;
      33             :         struct posix_acl_entry  a_entries[];
      34             : };
      35             : 
      36             : #define FOREACH_ACL_ENTRY(pa, acl, pe) \
      37             :         for(pa=(acl)->a_entries, pe=pa+(acl)->a_count; pa<pe; pa++)
      38             : 
      39             : 
      40             : /*
      41             :  * Duplicate an ACL handle.
      42             :  */
      43             : static inline struct posix_acl *
      44             : posix_acl_dup(struct posix_acl *acl)
      45             : {
      46             :         if (acl)
      47             :                 refcount_inc(&acl->a_refcount);
      48             :         return acl;
      49             : }
      50             : 
      51             : /*
      52             :  * Free an ACL handle.
      53             :  */
      54             : static inline void
      55           0 : posix_acl_release(struct posix_acl *acl)
      56             : {
      57           0 :         if (acl && refcount_dec_and_test(&acl->a_refcount))
      58           0 :                 kfree_rcu(acl, a_rcu);
      59           0 : }
      60             : 
      61             : 
      62             : /* posix_acl.c */
      63             : 
      64             : extern void posix_acl_init(struct posix_acl *, int);
      65             : extern struct posix_acl *posix_acl_alloc(int, gfp_t);
      66             : extern struct posix_acl *posix_acl_from_mode(umode_t, gfp_t);
      67             : extern int posix_acl_equiv_mode(const struct posix_acl *, umode_t *);
      68             : extern int __posix_acl_create(struct posix_acl **, gfp_t, umode_t *);
      69             : extern int __posix_acl_chmod(struct posix_acl **, gfp_t, umode_t);
      70             : 
      71             : extern struct posix_acl *get_posix_acl(struct inode *, int);
      72             : extern int set_posix_acl(struct user_namespace *, struct inode *, int,
      73             :                          struct posix_acl *);
      74             : 
      75             : #ifdef CONFIG_FS_POSIX_ACL
      76             : int posix_acl_chmod(struct user_namespace *, struct inode *, umode_t);
      77             : extern int posix_acl_create(struct inode *, umode_t *, struct posix_acl **,
      78             :                 struct posix_acl **);
      79             : int posix_acl_update_mode(struct user_namespace *, struct inode *, umode_t *,
      80             :                           struct posix_acl **);
      81             : 
      82             : extern int simple_set_acl(struct user_namespace *, struct inode *,
      83             :                           struct posix_acl *, int);
      84             : extern int simple_acl_create(struct inode *, struct inode *);
      85             : 
      86             : struct posix_acl *get_cached_acl(struct inode *inode, int type);
      87             : struct posix_acl *get_cached_acl_rcu(struct inode *inode, int type);
      88             : void set_cached_acl(struct inode *inode, int type, struct posix_acl *acl);
      89             : void forget_cached_acl(struct inode *inode, int type);
      90             : void forget_all_cached_acls(struct inode *inode);
      91             : int posix_acl_valid(struct user_namespace *, const struct posix_acl *);
      92             : int posix_acl_permission(struct user_namespace *, struct inode *,
      93             :                          const struct posix_acl *, int);
      94             : 
      95             : static inline void cache_no_acl(struct inode *inode)
      96             : {
      97             :         inode->i_acl = NULL;
      98             :         inode->i_default_acl = NULL;
      99             : }
     100             : #else
     101         143 : static inline int posix_acl_chmod(struct user_namespace *mnt_userns,
     102             :                                   struct inode *inode, umode_t mode)
     103             : {
     104         143 :         return 0;
     105             : }
     106             : 
     107             : #define simple_set_acl          NULL
     108             : 
     109        1427 : static inline int simple_acl_create(struct inode *dir, struct inode *inode)
     110             : {
     111        1427 :         return 0;
     112             : }
     113        1744 : static inline void cache_no_acl(struct inode *inode)
     114             : {
     115        1744 : }
     116             : 
     117             : static inline int posix_acl_create(struct inode *inode, umode_t *mode,
     118             :                 struct posix_acl **default_acl, struct posix_acl **acl)
     119             : {
     120             :         *default_acl = *acl = NULL;
     121             :         return 0;
     122             : }
     123             : 
     124             : static inline void forget_all_cached_acls(struct inode *inode)
     125             : {
     126             : }
     127             : #endif /* CONFIG_FS_POSIX_ACL */
     128             : 
     129             : struct posix_acl *get_acl(struct inode *inode, int type);
     130             : 
     131             : #endif  /* __LINUX_POSIX_ACL_H */