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 posix_acl_release(struct posix_acl *acl) 56 { 57 if (acl && refcount_dec_and_test(&acl->a_refcount)) 58 kfree_rcu(acl, a_rcu); 59 } 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 struct posix_acl *get_cached_acl_rcu(struct inode *inode, int type); 76 77 #ifdef CONFIG_FS_POSIX_ACL 78 int posix_acl_chmod(struct user_namespace *, struct inode *, umode_t); 79 extern int posix_acl_create(struct inode *, umode_t *, struct posix_acl **, 80 struct posix_acl **); 81 int posix_acl_update_mode(struct user_namespace *, struct inode *, umode_t *, 82 struct posix_acl **); 83 84 extern int simple_set_acl(struct user_namespace *, struct inode *, 85 struct posix_acl *, int); 86 extern int simple_acl_create(struct inode *, struct inode *); 87 88 struct posix_acl *get_cached_acl(struct inode *inode, int type); 89 void set_cached_acl(struct inode *inode, int type, struct posix_acl *acl); 90 void forget_cached_acl(struct inode *inode, int type); 91 void forget_all_cached_acls(struct inode *inode); 92 int posix_acl_valid(struct user_namespace *, const struct posix_acl *); 93 int posix_acl_permission(struct user_namespace *, struct inode *, 94 const struct posix_acl *, int); 95 96 static inline void cache_no_acl(struct inode *inode) 97 { 98 inode->i_acl = NULL; 99 inode->i_default_acl = NULL; 100 } 101 #else 102 static inline int posix_acl_chmod(struct user_namespace *mnt_userns, 103 struct inode *inode, umode_t mode) 104 { 105 return 0; 106 } 107 108 #define simple_set_acl NULL 109 110 static inline int simple_acl_create(struct inode *dir, struct inode *inode) 111 { 112 return 0; 113 } 114 static inline void cache_no_acl(struct inode *inode) 115 { 116 } 117 118 static inline int posix_acl_create(struct inode *inode, umode_t *mode, 119 struct posix_acl **default_acl, struct posix_acl **acl) 120 { 121 *default_acl = *acl = NULL; 122 return 0; 123 } 124 125 static inline void forget_all_cached_acls(struct inode *inode) 126 { 127 } 128 #endif /* CONFIG_FS_POSIX_ACL */ 129 130 struct posix_acl *get_acl(struct inode *inode, int type); 131 132 #endif /* __LINUX_POSIX_ACL_H */ 133