Home | History | Annotate | Line # | Download | only in ext2fs 
      1 /*	$NetBSD: ext2fs_xattr.h,v 1.4 2020/04/16 23:29:53 rin Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2016 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Jaromir Dolecek.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 #ifndef _UFS_EXT2FS_EXT2FS_XATTR_H_
     33 #define _UFS_EXT2FS_EXT2FS_XATTR_H_
     34 
     35 #include <sys/cdefs.h>
     36 __KERNEL_RCSID(0, "$NetBSD: ext2fs_xattr.h,v 1.4 2020/04/16 23:29:53 rin Exp $");
     37 
     38 #ifdef _KERNEL
     39 
     40 #define EXT2FS_XATTR_MAGIC 	0xEA020000
     41 
     42 #define EXT2FS_XATTR_NAME_LEN_MAX	255
     43 #define EXT2FS_XATTR_REFCOUNT_MAX	1024
     44 
     45 /*
     46  * This is used as header for extended attribute block within inode
     47  */
     48 struct ext2fs_xattr_ibody_header {
     49 	uint32_t h_magic;	/* Magic number - 0xEA020000 */
     50 };
     51 
     52 /*
     53  * This is used as header for extended attribute on separate disk block
     54  */
     55 struct ext2fs_xattr_header {
     56 	uint32_t h_magic;	/* Magic number - 0xEA020000 */
     57 	uint32_t h_refcount;	/* Reference count */
     58 	uint32_t h_blocks;	/* Number of blocks - only 1 supported */
     59 	uint32_t h_hash;	/* Hash of all attributes */
     60  	uint32_t h_checksum;	/* Checksum of the extended attribute block */
     61 	uint32_t h_reserved[3];
     62 };
     63 
     64 /*
     65  * Extended attribute on-disk header structure
     66  */
     67 struct ext2fs_xattr_entry {
     68         uint8_t  e_name_len;		/* Name length */
     69         uint8_t  e_name_index;		/* Name prefix index (see below) */
     70         uint16_t e_value_offs;		/* Offset of value within block */
     71         uint32_t e_value_block;		/* Value block - not supported (always zero) */
     72         uint32_t e_value_size;		/* Length of value */
     73         uint32_t e_hash;		/* Hash (not supported) */
     74         char e_name[0];			/* Name string (e_name_len bytes) */
     75 };
     76 
     77 /*
     78  * Linux kernel checks only the 0, we also check that the current entry
     79  * doesn't overflow past end.
     80  */
     81 #define EXT2FS_XATTR_IS_LAST_ENTRY(entry, end) \
     82 	(*((uint32_t *)(entry)) == 0 || (uintptr_t)EXT2FS_XATTR_NEXT(entry) > (uintptr_t)end)
     83 
     84 /*
     85  * Each ext2fs_xattr_entry starts on next 4-byte boundary, pad if necessary.
     86  */
     87 #define EXT2FS_XATTR_PAD	4
     88 #define EXT2FS_XATTR_ROUND	(EXT2FS_XATTR_PAD - 1)
     89 #define EXT2FS_XATTR_LEN(name_len) \
     90 	(((name_len) + EXT2FS_XATTR_ROUND + \
     91 	sizeof(struct ext2fs_xattr_entry)) & ~EXT2FS_XATTR_ROUND)
     92 #define EXT2FS_XATTR_NEXT(entry) \
     93 	(struct ext2fs_xattr_entry *)(((uint8_t *)(entry)) + EXT2FS_XATTR_LEN((entry)->e_name_len))
     94 
     95 #define EXT2FS_XATTR_IFIRST(h) (void *)&(h)[1]
     96 #define EXT2FS_XATTR_BFIRST(h) EXT2FS_XATTR_IFIRST(h)
     97 
     98 /*
     99  * Name prefixes
    100  */
    101 #define EXT2FS_XATTR_PREFIX_NONE		0 /* no prefix */
    102 #define EXT2FS_XATTR_PREFIX_USER		1 /* "user." */
    103 #define EXT2FS_XATTR_PREFIX_POSIX_ACCESS	2 /* "system.posix_acl_access" */
    104 #define EXT2FS_XATTR_PREFIX_POSIX_DEFAULT1	3 /* "system.posix_acl_default" */
    105 #define EXT2FS_XATTR_PREFIX_TRUSTED		4 /* "trusted." */
    106 #define EXT2FS_XATTR_PREFIX_SECURITY		6 /* "security." */
    107 #define EXT2FS_XATTR_PREFIX_SYSTEM		7 /* "system." */
    108 #define EXT2FS_XATTR_PREFIX_SYSTEM_RICHACL	8 /* "system.richacl" */
    109 #define EXT2FS_XATTR_PREFIX_ENCRYPTION		9 /* "c" */
    110 
    111 int ext2fs_getextattr(void *);
    112 int ext2fs_setextattr(void *);
    113 int ext2fs_listextattr(void *);
    114 int ext2fs_deleteextattr(void *);
    115 #endif /* _KERNEL */
    116 
    117 #endif /* _UFS_EXT2FS_EXT2FS_XATTR_H_ */
    118