| 1 | /* |
| 2 | File: linux/posix_acl.h |
| 3 | |
| 4 | (C) 2002 Andreas Gruenbacher, <a.gruenbacher@computer.org> |
| 5 | */ |
| 6 | |
| 7 | |
| 8 | #ifndef __LINUX_POSIX_ACL_H |
| 9 | #define __LINUX_POSIX_ACL_H |
| 10 | |
| 11 | #include <linux/bug.h> |
| 12 | #include <linux/slab.h> |
| 13 | #include <linux/rcupdate.h> |
| 14 | |
| 15 | #define ACL_UNDEFINED_ID (-1) |
| 16 | |
| 17 | /* a_type field in acl_user_posix_entry_t */ |
| 18 | #define ACL_TYPE_ACCESS (0x8000) |
| 19 | #define ACL_TYPE_DEFAULT (0x4000) |
| 20 | |
| 21 | /* e_tag entry in struct posix_acl_entry */ |
| 22 | #define ACL_USER_OBJ (0x01) |
| 23 | #define ACL_USER (0x02) |
| 24 | #define ACL_GROUP_OBJ (0x04) |
| 25 | #define ACL_GROUP (0x08) |
| 26 | #define ACL_MASK (0x10) |
| 27 | #define ACL_OTHER (0x20) |
| 28 | |
| 29 | /* permissions in the e_perm field */ |
| 30 | #define ACL_READ (0x04) |
| 31 | #define ACL_WRITE (0x02) |
| 32 | #define ACL_EXECUTE (0x01) |
| 33 | //#define ACL_ADD (0x08) |
| 34 | //#define ACL_DELETE (0x10) |
| 35 | |
| 36 | struct posix_acl_entry { |
| 37 | short e_tag; |
| 38 | unsigned short e_perm; |
| 39 | union { |
| 40 | kuid_t e_uid; |
| 41 | kgid_t e_gid; |
| 42 | }; |
| 43 | }; |
| 44 | |
| 45 | struct posix_acl { |
| 46 | union { |
| 47 | atomic_t a_refcount; |
| 48 | struct rcu_head a_rcu; |
| 49 | }; |
| 50 | unsigned int a_count; |
| 51 | struct posix_acl_entry a_entries[0]; |
| 52 | }; |
| 53 | |
| 54 | #define FOREACH_ACL_ENTRY(pa, acl, pe) \ |
| 55 | for(pa=(acl)->a_entries, pe=pa+(acl)->a_count; pa<pe; pa++) |
| 56 | |
| 57 | |
| 58 | /* |
| 59 | * Duplicate an ACL handle. |
| 60 | */ |
| 61 | static inline struct posix_acl * |
| 62 | posix_acl_dup(struct posix_acl *acl) |
| 63 | { |
| 64 | if (acl) |
| 65 | atomic_inc(&acl->a_refcount); |
| 66 | return acl; |
| 67 | } |
| 68 | |
| 69 | /* |
| 70 | * Free an ACL handle. |
| 71 | */ |
| 72 | static inline void |
| 73 | posix_acl_release(struct posix_acl *acl) |
| 74 | { |
| 75 | if (acl && atomic_dec_and_test(&acl->a_refcount)) |
| 76 | kfree_rcu(acl, a_rcu); |
| 77 | } |
| 78 | |
| 79 | |
| 80 | /* posix_acl.c */ |
| 81 | |
| 82 | extern void posix_acl_init(struct posix_acl *, int); |
| 83 | extern struct posix_acl *posix_acl_alloc(int, gfp_t); |
| 84 | extern int posix_acl_valid(const struct posix_acl *); |
| 85 | extern int posix_acl_permission(struct inode *, const struct posix_acl *, int); |
| 86 | extern struct posix_acl *posix_acl_from_mode(umode_t, gfp_t); |
| 87 | extern int posix_acl_equiv_mode(const struct posix_acl *, umode_t *); |
| 88 | extern int __posix_acl_create(struct posix_acl **, gfp_t, umode_t *); |
| 89 | extern int __posix_acl_chmod(struct posix_acl **, gfp_t, umode_t); |
| 90 | |
| 91 | extern struct posix_acl *get_posix_acl(struct inode *, int); |
| 92 | extern int set_posix_acl(struct inode *, int, struct posix_acl *); |
| 93 | |
| 94 | #ifdef CONFIG_FS_POSIX_ACL |
| 95 | extern int posix_acl_chmod(struct inode *, umode_t); |
| 96 | extern int posix_acl_create(struct inode *, umode_t *, struct posix_acl **, |
| 97 | struct posix_acl **); |
| 98 | |
| 99 | extern int simple_set_acl(struct inode *, struct posix_acl *, int); |
| 100 | extern int simple_acl_create(struct inode *, struct inode *); |
| 101 | |
| 102 | struct posix_acl *get_cached_acl(struct inode *inode, int type); |
| 103 | struct posix_acl *get_cached_acl_rcu(struct inode *inode, int type); |
| 104 | void set_cached_acl(struct inode *inode, int type, struct posix_acl *acl); |
| 105 | void forget_cached_acl(struct inode *inode, int type); |
| 106 | void forget_all_cached_acls(struct inode *inode); |
| 107 | |
| 108 | static inline void cache_no_acl(struct inode *inode) |
| 109 | { |
| 110 | inode->i_acl = NULL; |
| 111 | inode->i_default_acl = NULL; |
| 112 | } |
| 113 | #else |
| 114 | static inline int posix_acl_chmod(struct inode *inode, umode_t mode) |
| 115 | { |
| 116 | return 0; |
| 117 | } |
| 118 | |
| 119 | #define simple_set_acl NULL |
| 120 | |
| 121 | static inline int simple_acl_create(struct inode *dir, struct inode *inode) |
| 122 | { |
| 123 | return 0; |
| 124 | } |
| 125 | static inline void cache_no_acl(struct inode *inode) |
| 126 | { |
| 127 | } |
| 128 | |
| 129 | static inline int posix_acl_create(struct inode *inode, umode_t *mode, |
| 130 | struct posix_acl **default_acl, struct posix_acl **acl) |
| 131 | { |
| 132 | *default_acl = *acl = NULL; |
| 133 | return 0; |
| 134 | } |
| 135 | |
| 136 | static inline void forget_all_cached_acls(struct inode *inode) |
| 137 | { |
| 138 | } |
| 139 | #endif /* CONFIG_FS_POSIX_ACL */ |
| 140 | |
| 141 | struct posix_acl *get_acl(struct inode *inode, int type); |
| 142 | |
| 143 | #endif /* __LINUX_POSIX_ACL_H */ |