1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef GENL_MAGIC_STRUCT_H
3 #define GENL_MAGIC_STRUCT_H
4
5 #ifndef GENL_MAGIC_FAMILY
6 # error "you need to define GENL_MAGIC_FAMILY before inclusion"
7 #endif
8
9 #ifndef GENL_MAGIC_VERSION
10 # error "you need to define GENL_MAGIC_VERSION before inclusion"
11 #endif
12
13 #ifndef GENL_MAGIC_INCLUDE_FILE
14 # error "you need to define GENL_MAGIC_INCLUDE_FILE before inclusion"
15 #endif
16
17 #include <linux/genetlink.h>
18 #include <linux/types.h>
19
20 #define CONCAT__(a,b) a ## b
21 #define CONCAT_(a,b) CONCAT__(a,b)
22
23 extern int CONCAT_(GENL_MAGIC_FAMILY, _genl_register)(void);
24 extern void CONCAT_(GENL_MAGIC_FAMILY, _genl_unregister)(void);
25
26 /*
27 * Extension of genl attribute validation policies {{{2
28 */
29
30 /*
31 * @DRBD_GENLA_F_MANDATORY: By default, netlink ignores attributes it does not
32 * know about. This flag can be set in nlattr->nla_type to indicate that this
33 * attribute must not be ignored.
34 *
35 * We check and remove this flag in drbd_nla_check_mandatory() before
36 * validating the attribute types and lengths via nla_parse_nested().
37 */
38 #define DRBD_GENLA_F_MANDATORY (1 << 14)
39
40 /*
41 * Flags specific to drbd and not visible at the netlink layer, used in
42 * <struct>_from_attrs and <struct>_to_skb:
43 *
44 * @DRBD_F_REQUIRED: Attribute is required; a request without this attribute is
45 * invalid.
46 *
47 * @DRBD_F_SENSITIVE: Attribute includes sensitive information and must not be
48 * included in unpriviledged get requests or broadcasts.
49 *
50 * @DRBD_F_INVARIANT: Attribute is set when an object is initially created, but
51 * cannot subsequently be changed.
52 */
53 #define DRBD_F_REQUIRED (1 << 0)
54 #define DRBD_F_SENSITIVE (1 << 1)
55 #define DRBD_F_INVARIANT (1 << 2)
56
57 #define __nla_type(x) ((__u16)((x) & NLA_TYPE_MASK & ~DRBD_GENLA_F_MANDATORY))
58
59 /* }}}1
60 * MAGIC
61 * multi-include macro expansion magic starts here
62 */
63
64 /* MAGIC helpers {{{2 */
65
nla_put_u64_0pad(struct sk_buff * skb,int attrtype,u64 value)66 static inline int nla_put_u64_0pad(struct sk_buff *skb, int attrtype, u64 value)
67 {
68 return nla_put_64bit(skb, attrtype, sizeof(u64), &value, 0);
69 }
70
71 /* possible field types */
72 #define __flg_field(attr_nr, attr_flag, name) \
73 __field(attr_nr, attr_flag, name, NLA_U8, char, \
74 nla_get_u8, nla_put_u8, false)
75 #define __u8_field(attr_nr, attr_flag, name) \
76 __field(attr_nr, attr_flag, name, NLA_U8, unsigned char, \
77 nla_get_u8, nla_put_u8, false)
78 #define __u16_field(attr_nr, attr_flag, name) \
79 __field(attr_nr, attr_flag, name, NLA_U16, __u16, \
80 nla_get_u16, nla_put_u16, false)
81 #define __u32_field(attr_nr, attr_flag, name) \
82 __field(attr_nr, attr_flag, name, NLA_U32, __u32, \
83 nla_get_u32, nla_put_u32, false)
84 #define __s32_field(attr_nr, attr_flag, name) \
85 __field(attr_nr, attr_flag, name, NLA_U32, __s32, \
86 nla_get_u32, nla_put_u32, true)
87 #define __u64_field(attr_nr, attr_flag, name) \
88 __field(attr_nr, attr_flag, name, NLA_U64, __u64, \
89 nla_get_u64, nla_put_u64_0pad, false)
90 #define __str_field(attr_nr, attr_flag, name, maxlen) \
91 __array(attr_nr, attr_flag, name, NLA_NUL_STRING, char, maxlen, \
92 nla_strscpy, nla_put, false)
93 #define __bin_field(attr_nr, attr_flag, name, maxlen) \
94 __array(attr_nr, attr_flag, name, NLA_BINARY, char, maxlen, \
95 nla_memcpy, nla_put, false)
96
97 /* fields with default values */
98 #define __flg_field_def(attr_nr, attr_flag, name, default) \
99 __flg_field(attr_nr, attr_flag, name)
100 #define __u32_field_def(attr_nr, attr_flag, name, default) \
101 __u32_field(attr_nr, attr_flag, name)
102 #define __s32_field_def(attr_nr, attr_flag, name, default) \
103 __s32_field(attr_nr, attr_flag, name)
104 #define __str_field_def(attr_nr, attr_flag, name, maxlen) \
105 __str_field(attr_nr, attr_flag, name, maxlen)
106
107 #define GENL_op_init(args...) args
108 #define GENL_doit(handler) \
109 .doit = handler, \
110 .flags = GENL_ADMIN_PERM,
111 #define GENL_dumpit(handler) \
112 .dumpit = handler, \
113 .flags = GENL_ADMIN_PERM,
114
115 /* }}}1
116 * Magic: define the enum symbols for genl_ops
117 * Magic: define the enum symbols for top level attributes
118 * Magic: define the enum symbols for nested attributes
119 * {{{2
120 */
121
122 #undef GENL_struct
123 #define GENL_struct(tag_name, tag_number, s_name, s_fields)
124
125 #undef GENL_mc_group
126 #define GENL_mc_group(group)
127
128 #undef GENL_notification
129 #define GENL_notification(op_name, op_num, mcast_group, tla_list) \
130 op_name = op_num,
131
132 #undef GENL_op
133 #define GENL_op(op_name, op_num, handler, tla_list) \
134 op_name = op_num,
135
136 enum {
137 #include GENL_MAGIC_INCLUDE_FILE
138 };
139
140 #undef GENL_notification
141 #define GENL_notification(op_name, op_num, mcast_group, tla_list)
142
143 #undef GENL_op
144 #define GENL_op(op_name, op_num, handler, attr_list)
145
146 #undef GENL_struct
147 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \
148 tag_name = tag_number,
149
150 enum {
151 #include GENL_MAGIC_INCLUDE_FILE
152 };
153
154 #undef GENL_struct
155 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \
156 enum { \
157 s_fields \
158 };
159
160 #undef __field
161 #define __field(attr_nr, attr_flag, name, nla_type, type, \
162 __get, __put, __is_signed) \
163 T_ ## name = (__u16)(attr_nr | ((attr_flag) & DRBD_GENLA_F_MANDATORY)),
164
165 #undef __array
166 #define __array(attr_nr, attr_flag, name, nla_type, type, \
167 maxlen, __get, __put, __is_signed) \
168 T_ ## name = (__u16)(attr_nr | ((attr_flag) & DRBD_GENLA_F_MANDATORY)),
169
170 #include GENL_MAGIC_INCLUDE_FILE
171
172 /* }}}1
173 * Magic: compile time assert unique numbers for operations
174 * Magic: -"- unique numbers for top level attributes
175 * Magic: -"- unique numbers for nested attributes
176 * {{{2
177 */
178
179 #undef GENL_struct
180 #define GENL_struct(tag_name, tag_number, s_name, s_fields)
181
182 #undef GENL_op
183 #define GENL_op(op_name, op_num, handler, attr_list) \
184 case op_name:
185
186 #undef GENL_notification
187 #define GENL_notification(op_name, op_num, mcast_group, tla_list) \
188 case op_name:
189
ct_assert_unique_operations(void)190 static inline void ct_assert_unique_operations(void)
191 {
192 switch (0) {
193 #include GENL_MAGIC_INCLUDE_FILE
194 case 0:
195 ;
196 }
197 }
198
199 #undef GENL_op
200 #define GENL_op(op_name, op_num, handler, attr_list)
201
202 #undef GENL_notification
203 #define GENL_notification(op_name, op_num, mcast_group, tla_list)
204
205 #undef GENL_struct
206 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \
207 case tag_number:
208
ct_assert_unique_top_level_attributes(void)209 static inline void ct_assert_unique_top_level_attributes(void)
210 {
211 switch (0) {
212 #include GENL_MAGIC_INCLUDE_FILE
213 case 0:
214 ;
215 }
216 }
217
218 #undef GENL_struct
219 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \
220 static inline void ct_assert_unique_ ## s_name ## _attributes(void) \
221 { \
222 switch (0) { \
223 s_fields \
224 case 0: \
225 ; \
226 } \
227 }
228
229 #undef __field
230 #define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put, \
231 __is_signed) \
232 case attr_nr:
233
234 #undef __array
235 #define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, \
236 __get, __put, __is_signed) \
237 case attr_nr:
238
239 #include GENL_MAGIC_INCLUDE_FILE
240
241 /* }}}1
242 * Magic: declare structs
243 * struct <name> {
244 * fields
245 * };
246 * {{{2
247 */
248
249 #undef GENL_struct
250 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \
251 struct s_name { s_fields };
252
253 #undef __field
254 #define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put, \
255 __is_signed) \
256 type name;
257
258 #undef __array
259 #define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, \
260 __get, __put, __is_signed) \
261 type name[maxlen]; \
262 __u32 name ## _len;
263
264 #include GENL_MAGIC_INCLUDE_FILE
265
266 #undef GENL_struct
267 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \
268 enum { \
269 s_fields \
270 };
271
272 #undef __field
273 #define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put, \
274 is_signed) \
275 F_ ## name ## _IS_SIGNED = is_signed,
276
277 #undef __array
278 #define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, \
279 __get, __put, is_signed) \
280 F_ ## name ## _IS_SIGNED = is_signed,
281
282 #include GENL_MAGIC_INCLUDE_FILE
283
284 /* }}}1 */
285 #endif /* GENL_MAGIC_STRUCT_H */
286