LXR linux/fs/cifs/cifsacl.h

   1/*
   2 *   fs/cifs/cifsacl.h
   3 *
   4 *   Copyright (c) International Business Machines  Corp., 2007
   5 *   Author(s): Steve French (sfrench@us.ibm.com)
   6 *
   7 *   This library is free software; you can redistribute it and/or modify
   8 *   it under the terms of the GNU Lesser General Public License as published
   9 *   by the Free Software Foundation; either version 2.1 of the License, or
  10 *   (at your option) any later version.
  11 *
  12 *   This library is distributed in the hope that it will be useful,
  13 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  15 *   the GNU Lesser General Public License for more details.
  16 *
  17 *   You should have received a copy of the GNU Lesser General Public License
  18 *   along with this library; if not, write to the Free Software
  19 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  20 */
  21
  22#ifndef _CIFSACL_H
  23#define _CIFSACL_H
  24
  25
  26#define NUM_AUTHS (6)   /* number of authority fields */
  27#define SID_MAX_SUB_AUTHORITIES (15) /* max number of sub authority fields */
  28
  29#define READ_BIT        0x4
  30#define WRITE_BIT       0x2
  31#define EXEC_BIT        0x1
  32
  33#define UBITSHIFT       6
  34#define GBITSHIFT       3
  35
  36#define ACCESS_ALLOWED  0
  37#define ACCESS_DENIED   1
  38
  39#define SIDOWNER 1
  40#define SIDGROUP 2
  41
  42/*
  43 * Security Descriptor length containing DACL with 3 ACEs (one each for
  44 * owner, group and world).
  45 */
  46#define DEFAULT_SEC_DESC_LEN (sizeof(struct cifs_ntsd) + \
  47                              sizeof(struct cifs_acl) + \
  48                              (sizeof(struct cifs_ace) * 3))
  49
  50/*
  51 * Maximum size of a string representation of a SID:
  52 *
  53 * The fields are unsigned values in decimal. So:
  54 *
  55 * u8:  max 3 bytes in decimal
  56 * u32: max 10 bytes in decimal
  57 *
  58 * "S-" + 3 bytes for version field + 15 for authority field + NULL terminator
  59 *
  60 * For authority field, max is when all 6 values are non-zero and it must be
  61 * represented in hex. So "-0x" + 12 hex digits.
  62 *
  63 * Add 11 bytes for each subauthority field (10 bytes each + 1 for '-')
  64 */
  65#define SID_STRING_BASE_SIZE (2 + 3 + 15 + 1)
  66#define SID_STRING_SUBAUTH_SIZE (11) /* size of a single subauth string */
  67
  68struct cifs_ntsd {
  69        __le16 revision; /* revision level */
  70        __le16 type;
  71        __le32 osidoffset;
  72        __le32 gsidoffset;
  73        __le32 sacloffset;
  74        __le32 dacloffset;
  75} __attribute__((packed));
  76
  77struct cifs_sid {
  78        __u8 revision; /* revision level */
  79        __u8 num_subauth;
  80        __u8 authority[NUM_AUTHS];
  81        __le32 sub_auth[SID_MAX_SUB_AUTHORITIES]; /* sub_auth[num_subauth] */
  82} __attribute__((packed));
  83
  84/* size of a struct cifs_sid, sans sub_auth array */
  85#define CIFS_SID_BASE_SIZE (1 + 1 + NUM_AUTHS)
  86
  87struct cifs_acl {
  88        __le16 revision; /* revision level */
  89        __le16 size;
  90        __le32 num_aces;
  91} __attribute__((packed));
  92
  93struct cifs_ace {
  94        __u8 type;
  95        __u8 flags;
  96        __le16 size;
  97        __le32 access_req;
  98        struct cifs_sid sid; /* ie UUID of user or group who gets these perms */
  99} __attribute__((packed));
 100
 101#endif /* _CIFSACL_H */
 102