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 *
posix_acl_dup(struct posix_acl * 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
posix_acl_release(struct posix_acl * acl)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
cache_no_acl(struct inode * inode)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
posix_acl_chmod(struct mnt_idmap * idmap,struct dentry * dentry,umode_t mode)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
simple_acl_create(struct inode * dir,struct inode * inode)120 static inline int simple_acl_create(struct inode *dir, struct inode *inode)
121 {
122 return 0;
123 }
cache_no_acl(struct inode * inode)124 static inline void cache_no_acl(struct inode *inode)
125 {
126 }
127
posix_acl_create(struct inode * inode,umode_t * mode,struct posix_acl ** default_acl,struct posix_acl ** acl)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
forget_all_cached_acls(struct inode * inode)135 static inline void forget_all_cached_acls(struct inode *inode)
136 {
137 }
138
vfs_set_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * name,struct posix_acl * acl)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
vfs_get_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name)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
vfs_remove_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name)153 static inline int vfs_remove_acl(struct mnt_idmap *idmap,
154 struct dentry *dentry, const char *acl_name)
155 {
156 return -EOPNOTSUPP;
157 }
posix_acl_listxattr(struct inode * inode,char ** buffer,ssize_t * remaining_size)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
