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 <uapi/linux/posix_acl.h> 16 17 struct posix_acl_entry { 18 short e_tag; 19 unsigned short e_perm; 20 union { 21 kuid_t e_uid; 22 kgid_t e_gid; 23 }; 24 }; 25 26 struct posix_acl { 27 atomic_t a_refcount; 28 struct rcu_head a_rcu; 29 unsigned int a_count; 30 struct posix_acl_entry a_entries[0]; 31 }; 32 33 #define FOREACH_ACL_ENTRY(pa, acl, pe) \ 34 for(pa=(acl)->a_entries, pe=pa+(acl)->a_count; pa<pe; pa++) 35 36 37 /* 38 * Duplicate an ACL handle. 39 */ 40 static inline struct posix_acl * 41 posix_acl_dup(struct posix_acl *acl) 42 { 43 if (acl) 44 atomic_inc(&acl->a_refcount); 45 return acl; 46 } 47 48 /* 49 * Free an ACL handle. 50 */ 51 static inline void 52 posix_acl_release(struct posix_acl *acl) 53 { 54 if (acl && atomic_dec_and_test(&acl->a_refcount)) 55 kfree_rcu(acl, a_rcu); 56 } 57 58 59 /* posix_acl.c */ 60 61 extern void posix_acl_init(struct posix_acl *, int); 62 extern struct posix_acl *posix_acl_alloc(int, gfp_t); 63 extern int posix_acl_valid(struct user_namespace *, const struct posix_acl *); 64 extern int posix_acl_permission(struct inode *, const struct posix_acl *, int); 65 extern struct posix_acl *posix_acl_from_mode(umode_t, gfp_t); 66 extern int posix_acl_equiv_mode(const struct posix_acl *, umode_t *); 67 extern int __posix_acl_create(struct posix_acl **, gfp_t, umode_t *); 68 extern int __posix_acl_chmod(struct posix_acl **, gfp_t, umode_t); 69 70 extern struct posix_acl *get_posix_acl(struct inode *, int); 71 extern int set_posix_acl(struct inode *, int, struct posix_acl *); 72 73 #ifdef CONFIG_FS_POSIX_ACL 74 extern int posix_acl_chmod(struct inode *, umode_t); 75 extern int posix_acl_create(struct inode *, umode_t *, struct posix_acl **, 76 struct posix_acl **); 77 extern int posix_acl_update_mode(struct inode *, umode_t *, struct posix_acl **); 78 79 extern int simple_set_acl(struct inode *, struct posix_acl *, int); 80 extern int simple_acl_create(struct inode *, struct inode *); 81 82 struct posix_acl *get_cached_acl(struct inode *inode, int type); 83 struct posix_acl *get_cached_acl_rcu(struct inode *inode, int type); 84 void set_cached_acl(struct inode *inode, int type, struct posix_acl *acl); 85 void forget_cached_acl(struct inode *inode, int type); 86 void forget_all_cached_acls(struct inode *inode); 87 88 static inline void cache_no_acl(struct inode *inode) 89 { 90 inode->i_acl = NULL; 91 inode->i_default_acl = NULL; 92 } 93 #else 94 static inline int posix_acl_chmod(struct inode *inode, umode_t mode) 95 { 96 return 0; 97 } 98 99 #define simple_set_acl NULL 100 101 static inline int simple_acl_create(struct inode *dir, struct inode *inode) 102 { 103 return 0; 104 } 105 static inline void cache_no_acl(struct inode *inode) 106 { 107 } 108 109 static inline int posix_acl_create(struct inode *inode, umode_t *mode, 110 struct posix_acl **default_acl, struct posix_acl **acl) 111 { 112 *default_acl = *acl = NULL; 113 return 0; 114 } 115 116 static inline void forget_all_cached_acls(struct inode *inode) 117 { 118 } 119 #endif /* CONFIG_FS_POSIX_ACL */ 120 121 struct posix_acl *get_acl(struct inode *inode, int type); 122 123 #endif /* __LINUX_POSIX_ACL_H */ 124