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linux/fs/cifs/cifsacl.h
Jeff Layton 193cdd8a29 cifs: fix SID binary to string conversion
The authority fields are supposed to be represented by a single 48-bit
value. It's also supposed to represent the value as hex if it's equal to
or greater than 2^32. This is documented in MS-DTYP, section 2.4.2.1.

Also, fix up the max string length to account for this fix.

Acked-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2012-12-11 11:48:49 -06:00

102 lines
2.9 KiB
C

/*
* fs/cifs/cifsacl.h
*
* Copyright (c) International Business Machines Corp., 2007
* Author(s): Steve French (sfrench@us.ibm.com)
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
* the GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef _CIFSACL_H
#define _CIFSACL_H
#define NUM_AUTHS (6) /* number of authority fields */
#define SID_MAX_SUB_AUTHORITIES (15) /* max number of sub authority fields */
#define READ_BIT 0x4
#define WRITE_BIT 0x2
#define EXEC_BIT 0x1
#define UBITSHIFT 6
#define GBITSHIFT 3
#define ACCESS_ALLOWED 0
#define ACCESS_DENIED 1
#define SIDOWNER 1
#define SIDGROUP 2
/*
* Security Descriptor length containing DACL with 3 ACEs (one each for
* owner, group and world).
*/
#define DEFAULT_SEC_DESC_LEN (sizeof(struct cifs_ntsd) + \
sizeof(struct cifs_acl) + \
(sizeof(struct cifs_ace) * 3))
/*
* Maximum size of a string representation of a SID:
*
* The fields are unsigned values in decimal. So:
*
* u8: max 3 bytes in decimal
* u32: max 10 bytes in decimal
*
* "S-" + 3 bytes for version field + 15 for authority field + NULL terminator
*
* For authority field, max is when all 6 values are non-zero and it must be
* represented in hex. So "-0x" + 12 hex digits.
*
* Add 11 bytes for each subauthority field (10 bytes each + 1 for '-')
*/
#define SID_STRING_BASE_SIZE (2 + 3 + 15 + 1)
#define SID_STRING_SUBAUTH_SIZE (11) /* size of a single subauth string */
struct cifs_ntsd {
__le16 revision; /* revision level */
__le16 type;
__le32 osidoffset;
__le32 gsidoffset;
__le32 sacloffset;
__le32 dacloffset;
} __attribute__((packed));
struct cifs_sid {
__u8 revision; /* revision level */
__u8 num_subauth;
__u8 authority[NUM_AUTHS];
__le32 sub_auth[SID_MAX_SUB_AUTHORITIES]; /* sub_auth[num_subauth] */
} __attribute__((packed));
/* size of a struct cifs_sid, sans sub_auth array */
#define CIFS_SID_BASE_SIZE (1 + 1 + NUM_AUTHS)
struct cifs_acl {
__le16 revision; /* revision level */
__le16 size;
__le32 num_aces;
} __attribute__((packed));
struct cifs_ace {
__u8 type;
__u8 flags;
__le16 size;
__le32 access_req;
struct cifs_sid sid; /* ie UUID of user or group who gets these perms */
} __attribute__((packed));
#endif /* _CIFSACL_H */