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 **acl_by_type(struct inode *inode, int type); 103 struct posix_acl *get_cached_acl(struct inode *inode, int type); 104 struct posix_acl *get_cached_acl_rcu(struct inode *inode, int type); 105 void set_cached_acl(struct inode *inode, int type, struct posix_acl *acl); 106 void forget_cached_acl(struct inode *inode, int type); 107 void forget_all_cached_acls(struct inode *inode); 108 109 static inline void cache_no_acl(struct inode *inode) 110 { 111 inode->i_acl = NULL; 112 inode->i_default_acl = NULL; 113 } 114 #else 115 static inline int posix_acl_chmod(struct inode *inode, umode_t mode) 116 { 117 return 0; 118 } 119 120 #define simple_set_acl NULL 121 122 static inline int simple_acl_create(struct inode *dir, struct inode *inode) 123 { 124 return 0; 125 } 126 static inline void cache_no_acl(struct inode *inode) 127 { 128 } 129 130 static inline int posix_acl_create(struct inode *inode, umode_t *mode, 131 struct posix_acl **default_acl, struct posix_acl **acl) 132 { 133 *default_acl = *acl = NULL; 134 return 0; 135 } 136 137 static inline void forget_all_cached_acls(struct inode *inode) 138 { 139 } 140 #endif /* CONFIG_FS_POSIX_ACL */ 141 142 struct posix_acl *get_acl(struct inode *inode, int type); 143 144 #endif /* __LINUX_POSIX_ACL_H */ 145