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 int set_posix_acl(struct mnt_idmap *, struct dentry *, int, 73 struct posix_acl *); 74 75 struct posix_acl *get_cached_acl_rcu(struct inode *inode, int type); 76 struct posix_acl *posix_acl_clone(const struct posix_acl *acl, gfp_t flags); 77 78 #ifdef CONFIG_FS_POSIX_ACL 79 int posix_acl_chmod(struct mnt_idmap *, struct dentry *, umode_t); 80 extern int posix_acl_create(struct inode *, umode_t *, struct posix_acl **, 81 struct posix_acl **); 82 int posix_acl_update_mode(struct mnt_idmap *, struct inode *, umode_t *, 83 struct posix_acl **); 84 85 int simple_set_acl(struct mnt_idmap *, struct dentry *, 86 struct posix_acl *, int); 87 extern int simple_acl_create(struct inode *, struct inode *); 88 89 struct posix_acl *get_cached_acl(struct inode *inode, int type); 90 void set_cached_acl(struct inode *inode, int type, struct posix_acl *acl); 91 void forget_cached_acl(struct inode *inode, int type); 92 void forget_all_cached_acls(struct inode *inode); 93 int posix_acl_valid(struct user_namespace *, const struct posix_acl *); 94 int posix_acl_permission(struct mnt_idmap *, struct inode *, 95 const struct posix_acl *, int); 96 97 static inline void cache_no_acl(struct inode *inode) 98 { 99 inode->i_acl = NULL; 100 inode->i_default_acl = NULL; 101 } 102 103 int vfs_set_acl(struct mnt_idmap *idmap, struct dentry *dentry, 104 const char *acl_name, struct posix_acl *kacl); 105 struct posix_acl *vfs_get_acl(struct mnt_idmap *idmap, 106 struct dentry *dentry, const char *acl_name); 107 int vfs_remove_acl(struct mnt_idmap *idmap, struct dentry *dentry, 108 const char *acl_name); 109 int posix_acl_listxattr(struct inode *inode, char **buffer, 110 ssize_t *remaining_size); 111 #else 112 static inline int posix_acl_chmod(struct mnt_idmap *idmap, 113 struct dentry *dentry, umode_t mode) 114 { 115 return 0; 116 } 117 118 #define simple_set_acl NULL 119 120 static inline int simple_acl_create(struct inode *dir, struct inode *inode) 121 { 122 return 0; 123 } 124 static inline void cache_no_acl(struct inode *inode) 125 { 126 } 127 128 static inline int posix_acl_create(struct inode *inode, umode_t *mode, 129 struct posix_acl **default_acl, struct posix_acl **acl) 130 { 131 *default_acl = *acl = NULL; 132 return 0; 133 } 134 135 static inline void forget_all_cached_acls(struct inode *inode) 136 { 137 } 138 139 static inline int vfs_set_acl(struct mnt_idmap *idmap, 140 struct dentry *dentry, const char *name, 141 struct posix_acl *acl) 142 { 143 return -EOPNOTSUPP; 144 } 145 146 static inline struct posix_acl *vfs_get_acl(struct mnt_idmap *idmap, 147 struct dentry *dentry, 148 const char *acl_name) 149 { 150 return ERR_PTR(-EOPNOTSUPP); 151 } 152 153 static inline int vfs_remove_acl(struct mnt_idmap *idmap, 154 struct dentry *dentry, const char *acl_name) 155 { 156 return -EOPNOTSUPP; 157 } 158 static inline int posix_acl_listxattr(struct inode *inode, char **buffer, 159 ssize_t *remaining_size) 160 { 161 return 0; 162 } 163 #endif /* CONFIG_FS_POSIX_ACL */ 164 165 struct posix_acl *get_inode_acl(struct inode *inode, int type); 166 167 #endif /* __LINUX_POSIX_ACL_H */ 168