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 atomic_t a_refcount; 47 struct rcu_head a_rcu; 48 unsigned int a_count; 49 struct posix_acl_entry a_entries[0]; 50 }; 51 52 #define FOREACH_ACL_ENTRY(pa, acl, pe) \ 53 for(pa=(acl)->a_entries, pe=pa+(acl)->a_count; pa<pe; pa++) 54 55 56 /* 57 * Duplicate an ACL handle. 58 */ 59 static inline struct posix_acl * 60 posix_acl_dup(struct posix_acl *acl) 61 { 62 if (acl) 63 atomic_inc(&acl->a_refcount); 64 return acl; 65 } 66 67 /* 68 * Free an ACL handle. 69 */ 70 static inline void 71 posix_acl_release(struct posix_acl *acl) 72 { 73 if (acl && atomic_dec_and_test(&acl->a_refcount)) 74 kfree_rcu(acl, a_rcu); 75 } 76 77 78 /* posix_acl.c */ 79 80 extern void posix_acl_init(struct posix_acl *, int); 81 extern struct posix_acl *posix_acl_alloc(int, gfp_t); 82 extern int posix_acl_valid(struct user_namespace *, const struct posix_acl *); 83 extern int posix_acl_permission(struct inode *, const struct posix_acl *, int); 84 extern struct posix_acl *posix_acl_from_mode(umode_t, gfp_t); 85 extern int posix_acl_equiv_mode(const struct posix_acl *, umode_t *); 86 extern int __posix_acl_create(struct posix_acl **, gfp_t, umode_t *); 87 extern int __posix_acl_chmod(struct posix_acl **, gfp_t, umode_t); 88 89 extern struct posix_acl *get_posix_acl(struct inode *, int); 90 extern int set_posix_acl(struct inode *, int, struct posix_acl *); 91 92 #ifdef CONFIG_FS_POSIX_ACL 93 extern int posix_acl_chmod(struct inode *, umode_t); 94 extern int posix_acl_create(struct inode *, umode_t *, struct posix_acl **, 95 struct posix_acl **); 96 97 extern int simple_set_acl(struct inode *, struct posix_acl *, int); 98 extern int simple_acl_create(struct inode *, struct inode *); 99 100 struct posix_acl *get_cached_acl(struct inode *inode, int type); 101 struct posix_acl *get_cached_acl_rcu(struct inode *inode, int type); 102 void set_cached_acl(struct inode *inode, int type, struct posix_acl *acl); 103 void forget_cached_acl(struct inode *inode, int type); 104 void forget_all_cached_acls(struct inode *inode); 105 106 static inline void cache_no_acl(struct inode *inode) 107 { 108 inode->i_acl = NULL; 109 inode->i_default_acl = NULL; 110 } 111 #else 112 static inline int posix_acl_chmod(struct inode *inode, umode_t mode) 113 { 114 return 0; 115 } 116 117 #define simple_set_acl NULL 118 119 static inline int simple_acl_create(struct inode *dir, struct inode *inode) 120 { 121 return 0; 122 } 123 static inline void cache_no_acl(struct inode *inode) 124 { 125 } 126 127 static inline int posix_acl_create(struct inode *inode, umode_t *mode, 128 struct posix_acl **default_acl, struct posix_acl **acl) 129 { 130 *default_acl = *acl = NULL; 131 return 0; 132 } 133 134 static inline void forget_all_cached_acls(struct inode *inode) 135 { 136 } 137 #endif /* CONFIG_FS_POSIX_ACL */ 138 139 struct posix_acl *get_acl(struct inode *inode, int type); 140 141 #endif /* __LINUX_POSIX_ACL_H */ 142