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

source code of linux/include/linux/genl_magic_struct.h