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 posix_acl_entry { 19 short e_tag; 20 unsigned short e_perm; 21 union { 22 kuid_t e_uid; 23 kgid_t e_gid; 24 }; 25 }; 26 27 struct posix_acl { 28 refcount_t a_refcount; 29 struct rcu_head a_rcu; 30 unsigned int a_count; 31 struct posix_acl_entry a_entries[]; 32 }; 33 34 #define FOREACH_ACL_ENTRY(pa, acl, pe) \ 35 for(pa=(acl)->a_entries, pe=pa+(acl)->a_count; pa<pe; pa++) 36 37 38 /* 39 * Duplicate an ACL handle. 40 */ 41 static inline struct posix_acl * 42 posix_acl_dup(struct posix_acl *acl) 43 { 44 if (acl) 45 refcount_inc(&acl->a_refcount); 46 return acl; 47 } 48 49 /* 50 * Free an ACL handle. 51 */ 52 static inline void 53 posix_acl_release(struct posix_acl *acl) 54 { 55 if (acl && refcount_dec_and_test(&acl->a_refcount)) 56 kfree_rcu(acl, a_rcu); 57 } 58 59 60 /* posix_acl.c */ 61 62 extern void posix_acl_init(struct posix_acl *, int); 63 extern struct posix_acl *posix_acl_alloc(int, gfp_t); 64 extern int posix_acl_valid(struct user_namespace *, const struct posix_acl *); 65 extern int posix_acl_permission(struct inode *, const struct posix_acl *, int); 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 inode *, int, struct posix_acl *); 73 74 #ifdef CONFIG_FS_POSIX_ACL 75 extern int posix_acl_chmod(struct inode *, umode_t); 76 extern int posix_acl_create(struct inode *, umode_t *, struct posix_acl **, 77 struct posix_acl **); 78 extern int posix_acl_update_mode(struct inode *, umode_t *, struct posix_acl **); 79 80 extern int simple_set_acl(struct inode *, struct posix_acl *, int); 81 extern int simple_acl_create(struct inode *, struct inode *); 82 83 struct posix_acl *get_cached_acl(struct inode *inode, int type); 84 struct posix_acl *get_cached_acl_rcu(struct inode *inode, int type); 85 void set_cached_acl(struct inode *inode, int type, struct posix_acl *acl); 86 void forget_cached_acl(struct inode *inode, int type); 87 void forget_all_cached_acls(struct inode *inode); 88 89 static inline void cache_no_acl(struct inode *inode) 90 { 91 inode->i_acl = NULL; 92 inode->i_default_acl = NULL; 93 } 94 #else 95 static inline int posix_acl_chmod(struct inode *inode, umode_t mode) 96 { 97 return 0; 98 } 99 100 #define simple_set_acl NULL 101 102 static inline int simple_acl_create(struct inode *dir, struct inode *inode) 103 { 104 return 0; 105 } 106 static inline void cache_no_acl(struct inode *inode) 107 { 108 } 109 110 static inline int posix_acl_create(struct inode *inode, umode_t *mode, 111 struct posix_acl **default_acl, struct posix_acl **acl) 112 { 113 *default_acl = *acl = NULL; 114 return 0; 115 } 116 117 static inline void forget_all_cached_acls(struct inode *inode) 118 { 119 } 120 #endif /* CONFIG_FS_POSIX_ACL */ 121 122 struct posix_acl *get_acl(struct inode *inode, int type); 123 124 #endif /* __LINUX_POSIX_ACL_H */ 125