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) * 4))
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 
68 struct 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 
77 struct 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 
87 struct cifs_acl {
88 	__le16 revision; /* revision level */
89 	__le16 size;
90 	__le32 num_aces;
91 } __attribute__((packed));
92 
93 /* ACE types - see MS-DTYP 2.4.4.1 */
94 #define ACCESS_ALLOWED_ACE_TYPE	0x00
95 #define ACCESS_DENIED_ACE_TYPE	0x01
96 #define SYSTEM_AUDIT_ACE_TYPE	0x02
97 #define SYSTEM_ALARM_ACE_TYPE	0x03
98 #define ACCESS_ALLOWED_COMPOUND_ACE_TYPE 0x04
99 #define ACCESS_ALLOWED_OBJECT_ACE_TYPE	0x05
100 #define ACCESS_DENIED_OBJECT_ACE_TYPE	0x06
101 #define SYSTEM_AUDIT_OBJECT_ACE_TYPE	0x07
102 #define SYSTEM_ALARM_OBJECT_ACE_TYPE	0x08
103 #define ACCESS_ALLOWED_CALLBACK_ACE_TYPE 0x09
104 #define ACCESS_DENIED_CALLBACK_ACE_TYPE	0x0A
105 #define ACCESS_ALLOWED_CALLBACK_OBJECT_ACE_TYPE 0x0B
106 #define ACCESS_DENIED_CALLBACK_OBJECT_ACE_TYPE  0x0C
107 #define SYSTEM_AUDIT_CALLBACK_ACE_TYPE	0x0D
108 #define SYSTEM_ALARM_CALLBACK_ACE_TYPE	0x0E /* Reserved */
109 #define SYSTEM_AUDIT_CALLBACK_OBJECT_ACE_TYPE 0x0F
110 #define SYSTEM_ALARM_CALLBACK_OBJECT_ACE_TYPE 0x10 /* reserved */
111 #define SYSTEM_MANDATORY_LABEL_ACE_TYPE	0x11
112 #define SYSTEM_RESOURCE_ATTRIBUTE_ACE_TYPE 0x12
113 #define SYSTEM_SCOPED_POLICY_ID_ACE_TYPE 0x13
114 
115 /* ACE flags */
116 #define OBJECT_INHERIT_ACE	0x01
117 #define CONTAINER_INHERIT_ACE	0x02
118 #define NO_PROPAGATE_INHERIT_ACE 0x04
119 #define INHERIT_ONLY_ACE	0x08
120 #define INHERITED_ACE		0x10
121 #define SUCCESSFUL_ACCESS_ACE_FLAG 0x40
122 #define FAILED_ACCESS_ACE_FLAG	0x80
123 
124 struct cifs_ace {
125 	__u8 type; /* see above and MS-DTYP 2.4.4.1 */
126 	__u8 flags;
127 	__le16 size;
128 	__le32 access_req;
129 	struct cifs_sid sid; /* ie UUID of user or group who gets these perms */
130 } __attribute__((packed));
131 
132 /*
133  * The current SMB3 form of security descriptor is similar to what was used for
134  * cifs (see above) but some fields are split, and fields in the struct below
135  * matches names of fields to the spec, MS-DTYP (see sections 2.4.5 and
136  * 2.4.6). Note that "CamelCase" fields are used in this struct in order to
137  * match the MS-DTYP and MS-SMB2 specs which define the wire format.
138  */
139 struct smb3_sd {
140 	__u8 Revision; /* revision level, MUST be one */
141 	__u8 Sbz1; /* only meaningful if 'RM' flag set below */
142 	__le16 Control;
143 	__le32 OffsetOwner;
144 	__le32 OffsetGroup;
145 	__le32 OffsetSacl;
146 	__le32 OffsetDacl;
147 } __packed;
148 
149 /* Meaning of 'Control' field flags */
150 #define ACL_CONTROL_SR	0x8000	/* Self relative */
151 #define ACL_CONTROL_RM	0x4000	/* Resource manager control bits */
152 #define ACL_CONTROL_PS	0x2000	/* SACL protected from inherits */
153 #define ACL_CONTROL_PD	0x1000	/* DACL protected from inherits */
154 #define ACL_CONTROL_SI	0x0800	/* SACL Auto-Inherited */
155 #define ACL_CONTROL_DI	0x0400	/* DACL Auto-Inherited */
156 #define ACL_CONTROL_SC	0x0200	/* SACL computed through inheritance */
157 #define ACL_CONTROL_DC	0x0100	/* DACL computed through inheritence */
158 #define ACL_CONTROL_SS	0x0080	/* Create server ACL */
159 #define ACL_CONTROL_DT	0x0040	/* DACL provided by trusted source */
160 #define ACL_CONTROL_SD	0x0020	/* SACL defaulted */
161 #define ACL_CONTROL_SP	0x0010	/* SACL is present on object */
162 #define ACL_CONTROL_DD	0x0008	/* DACL defaulted */
163 #define ACL_CONTROL_DP	0x0004	/* DACL is present on object */
164 #define ACL_CONTROL_GD	0x0002	/* Group was defaulted */
165 #define ACL_CONTROL_OD	0x0001	/* User was defaulted */
166 
167 /* Meaning of AclRevision flags */
168 #define ACL_REVISION	0x02 /* See section 2.4.4.1 of MS-DTYP */
169 #define ACL_REVISION_DS	0x04 /* Additional AceTypes allowed */
170 
171 struct smb3_acl {
172 	u8 AclRevision; /* revision level */
173 	u8 Sbz1; /* MBZ */
174 	__le16 AclSize;
175 	__le16 AceCount;
176 	__le16 Sbz2; /* MBZ */
177 } __packed;
178 
179 /*
180  * Used to store the special 'NFS SIDs' used to persist the POSIX uid and gid
181  * See http://technet.microsoft.com/en-us/library/hh509017(v=ws.10).aspx
182  */
183 struct owner_sid {
184 	u8 Revision;
185 	u8 NumAuth;
186 	u8 Authority[6];
187 	__le32 SubAuthorities[3];
188 } __packed;
189 
190 struct owner_group_sids {
191 	struct owner_sid owner;
192 	struct owner_sid group;
193 } __packed;
194 
195 /*
196  * Minimum security identifier can be one for system defined Users
197  * and Groups such as NULL SID and World or Built-in accounts such
198  * as Administrator and Guest and consists of
199  * Revision + Num (Sub)Auths + Authority + Domain (one Subauthority)
200  */
201 #define MIN_SID_LEN  (1 + 1 + 6 + 4) /* in bytes */
202 
203 /*
204  * Minimum security descriptor can be one without any SACL and DACL and can
205  * consist of revision, type, and two sids of minimum size for owner and group
206  */
207 #define MIN_SEC_DESC_LEN  (sizeof(struct cifs_ntsd) + (2 * MIN_SID_LEN))
208 
209 #endif /* _CIFSACL_H */
210