xref: /linux/fs/smb/client/cifsacl.h (revision 0526b56cbc3c489642bd6a5fe4b718dea7ef0ee8)
1 /* SPDX-License-Identifier: LGPL-2.1 */
2 /*
3  *
4  *   Copyright (c) International Business Machines  Corp., 2007
5  *   Author(s): Steve French (sfrench@us.ibm.com)
6  *
7  */
8 
9 #ifndef _CIFSACL_H
10 #define _CIFSACL_H
11 
12 #define NUM_AUTHS (6)	/* number of authority fields */
13 #define SID_MAX_SUB_AUTHORITIES (15) /* max number of sub authority fields */
14 
15 #define READ_BIT        0x4
16 #define WRITE_BIT       0x2
17 #define EXEC_BIT        0x1
18 
19 #define ACL_OWNER_MASK 0700
20 #define ACL_GROUP_MASK 0070
21 #define ACL_EVERYONE_MASK 0007
22 
23 #define UBITSHIFT	6
24 #define GBITSHIFT	3
25 
26 #define ACCESS_ALLOWED	0
27 #define ACCESS_DENIED	1
28 
29 #define SIDOWNER 1
30 #define SIDGROUP 2
31 
32 /*
33  * Security Descriptor length containing DACL with 3 ACEs (one each for
34  * owner, group and world).
35  */
36 #define DEFAULT_SEC_DESC_LEN (sizeof(struct cifs_ntsd) + \
37 			      sizeof(struct cifs_acl) + \
38 			      (sizeof(struct cifs_ace) * 4))
39 
40 /*
41  * Maximum size of a string representation of a SID:
42  *
43  * The fields are unsigned values in decimal. So:
44  *
45  * u8:  max 3 bytes in decimal
46  * u32: max 10 bytes in decimal
47  *
48  * "S-" + 3 bytes for version field + 15 for authority field + NULL terminator
49  *
50  * For authority field, max is when all 6 values are non-zero and it must be
51  * represented in hex. So "-0x" + 12 hex digits.
52  *
53  * Add 11 bytes for each subauthority field (10 bytes each + 1 for '-')
54  */
55 #define SID_STRING_BASE_SIZE (2 + 3 + 15 + 1)
56 #define SID_STRING_SUBAUTH_SIZE (11) /* size of a single subauth string */
57 
58 struct cifs_ntsd {
59 	__le16 revision; /* revision level */
60 	__le16 type;
61 	__le32 osidoffset;
62 	__le32 gsidoffset;
63 	__le32 sacloffset;
64 	__le32 dacloffset;
65 } __attribute__((packed));
66 
67 struct cifs_sid {
68 	__u8 revision; /* revision level */
69 	__u8 num_subauth;
70 	__u8 authority[NUM_AUTHS];
71 	__le32 sub_auth[SID_MAX_SUB_AUTHORITIES]; /* sub_auth[num_subauth] */
72 } __attribute__((packed));
73 
74 /* size of a struct cifs_sid, sans sub_auth array */
75 #define CIFS_SID_BASE_SIZE (1 + 1 + NUM_AUTHS)
76 
77 struct cifs_acl {
78 	__le16 revision; /* revision level */
79 	__le16 size;
80 	__le32 num_aces;
81 } __attribute__((packed));
82 
83 /* ACE types - see MS-DTYP 2.4.4.1 */
84 #define ACCESS_ALLOWED_ACE_TYPE	0x00
85 #define ACCESS_DENIED_ACE_TYPE	0x01
86 #define SYSTEM_AUDIT_ACE_TYPE	0x02
87 #define SYSTEM_ALARM_ACE_TYPE	0x03
88 #define ACCESS_ALLOWED_COMPOUND_ACE_TYPE 0x04
89 #define ACCESS_ALLOWED_OBJECT_ACE_TYPE	0x05
90 #define ACCESS_DENIED_OBJECT_ACE_TYPE	0x06
91 #define SYSTEM_AUDIT_OBJECT_ACE_TYPE	0x07
92 #define SYSTEM_ALARM_OBJECT_ACE_TYPE	0x08
93 #define ACCESS_ALLOWED_CALLBACK_ACE_TYPE 0x09
94 #define ACCESS_DENIED_CALLBACK_ACE_TYPE	0x0A
95 #define ACCESS_ALLOWED_CALLBACK_OBJECT_ACE_TYPE 0x0B
96 #define ACCESS_DENIED_CALLBACK_OBJECT_ACE_TYPE  0x0C
97 #define SYSTEM_AUDIT_CALLBACK_ACE_TYPE	0x0D
98 #define SYSTEM_ALARM_CALLBACK_ACE_TYPE	0x0E /* Reserved */
99 #define SYSTEM_AUDIT_CALLBACK_OBJECT_ACE_TYPE 0x0F
100 #define SYSTEM_ALARM_CALLBACK_OBJECT_ACE_TYPE 0x10 /* reserved */
101 #define SYSTEM_MANDATORY_LABEL_ACE_TYPE	0x11
102 #define SYSTEM_RESOURCE_ATTRIBUTE_ACE_TYPE 0x12
103 #define SYSTEM_SCOPED_POLICY_ID_ACE_TYPE 0x13
104 
105 /* ACE flags */
106 #define OBJECT_INHERIT_ACE	0x01
107 #define CONTAINER_INHERIT_ACE	0x02
108 #define NO_PROPAGATE_INHERIT_ACE 0x04
109 #define INHERIT_ONLY_ACE	0x08
110 #define INHERITED_ACE		0x10
111 #define SUCCESSFUL_ACCESS_ACE_FLAG 0x40
112 #define FAILED_ACCESS_ACE_FLAG	0x80
113 
114 struct cifs_ace {
115 	__u8 type; /* see above and MS-DTYP 2.4.4.1 */
116 	__u8 flags;
117 	__le16 size;
118 	__le32 access_req;
119 	struct cifs_sid sid; /* ie UUID of user or group who gets these perms */
120 } __attribute__((packed));
121 
122 /*
123  * The current SMB3 form of security descriptor is similar to what was used for
124  * cifs (see above) but some fields are split, and fields in the struct below
125  * matches names of fields to the spec, MS-DTYP (see sections 2.4.5 and
126  * 2.4.6). Note that "CamelCase" fields are used in this struct in order to
127  * match the MS-DTYP and MS-SMB2 specs which define the wire format.
128  */
129 struct smb3_sd {
130 	__u8 Revision; /* revision level, MUST be one */
131 	__u8 Sbz1; /* only meaningful if 'RM' flag set below */
132 	__le16 Control;
133 	__le32 OffsetOwner;
134 	__le32 OffsetGroup;
135 	__le32 OffsetSacl;
136 	__le32 OffsetDacl;
137 } __packed;
138 
139 /* Meaning of 'Control' field flags */
140 #define ACL_CONTROL_SR	0x8000	/* Self relative */
141 #define ACL_CONTROL_RM	0x4000	/* Resource manager control bits */
142 #define ACL_CONTROL_PS	0x2000	/* SACL protected from inherits */
143 #define ACL_CONTROL_PD	0x1000	/* DACL protected from inherits */
144 #define ACL_CONTROL_SI	0x0800	/* SACL Auto-Inherited */
145 #define ACL_CONTROL_DI	0x0400	/* DACL Auto-Inherited */
146 #define ACL_CONTROL_SC	0x0200	/* SACL computed through inheritance */
147 #define ACL_CONTROL_DC	0x0100	/* DACL computed through inheritence */
148 #define ACL_CONTROL_SS	0x0080	/* Create server ACL */
149 #define ACL_CONTROL_DT	0x0040	/* DACL provided by trusted source */
150 #define ACL_CONTROL_SD	0x0020	/* SACL defaulted */
151 #define ACL_CONTROL_SP	0x0010	/* SACL is present on object */
152 #define ACL_CONTROL_DD	0x0008	/* DACL defaulted */
153 #define ACL_CONTROL_DP	0x0004	/* DACL is present on object */
154 #define ACL_CONTROL_GD	0x0002	/* Group was defaulted */
155 #define ACL_CONTROL_OD	0x0001	/* User was defaulted */
156 
157 /* Meaning of AclRevision flags */
158 #define ACL_REVISION	0x02 /* See section 2.4.4.1 of MS-DTYP */
159 #define ACL_REVISION_DS	0x04 /* Additional AceTypes allowed */
160 
161 struct smb3_acl {
162 	u8 AclRevision; /* revision level */
163 	u8 Sbz1; /* MBZ */
164 	__le16 AclSize;
165 	__le16 AceCount;
166 	__le16 Sbz2; /* MBZ */
167 } __packed;
168 
169 /*
170  * Used to store the special 'NFS SIDs' used to persist the POSIX uid and gid
171  * See http://technet.microsoft.com/en-us/library/hh509017(v=ws.10).aspx
172  */
173 struct owner_sid {
174 	u8 Revision;
175 	u8 NumAuth;
176 	u8 Authority[6];
177 	__le32 SubAuthorities[3];
178 } __packed;
179 
180 struct owner_group_sids {
181 	struct owner_sid owner;
182 	struct owner_sid group;
183 } __packed;
184 
185 /*
186  * Minimum security identifier can be one for system defined Users
187  * and Groups such as NULL SID and World or Built-in accounts such
188  * as Administrator and Guest and consists of
189  * Revision + Num (Sub)Auths + Authority + Domain (one Subauthority)
190  */
191 #define MIN_SID_LEN  (1 + 1 + 6 + 4) /* in bytes */
192 
193 /*
194  * Minimum security descriptor can be one without any SACL and DACL and can
195  * consist of revision, type, and two sids of minimum size for owner and group
196  */
197 #define MIN_SEC_DESC_LEN  (sizeof(struct cifs_ntsd) + (2 * MIN_SID_LEN))
198 
199 #endif /* _CIFSACL_H */
200