1 /* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */
2 #ifndef __YNL_C_PRIV_H
3 #define __YNL_C_PRIV_H 1
4
5 #include <stdbool.h>
6 #include <stddef.h>
7 #include <linux/types.h>
8
9 struct ynl_parse_arg;
10
11 /*
12 * YNL internals / low level stuff
13 */
14
15 enum ynl_policy_type {
16 YNL_PT_REJECT = 1,
17 YNL_PT_IGNORE,
18 YNL_PT_NEST,
19 YNL_PT_FLAG,
20 YNL_PT_BINARY,
21 YNL_PT_U8,
22 YNL_PT_U16,
23 YNL_PT_U32,
24 YNL_PT_U64,
25 YNL_PT_UINT,
26 YNL_PT_NUL_STR,
27 YNL_PT_BITFIELD32,
28 };
29
30 enum ynl_parse_result {
31 YNL_PARSE_CB_ERROR = -1,
32 YNL_PARSE_CB_STOP = 0,
33 YNL_PARSE_CB_OK = 1,
34 };
35
36 #define YNL_SOCKET_BUFFER_SIZE (1 << 17)
37
38 #define YNL_ARRAY_SIZE(array) (sizeof(array) ? \
39 sizeof(array) / sizeof(array[0]) : 0)
40
41 typedef int (*ynl_parse_cb_t)(const struct nlmsghdr *nlh,
42 struct ynl_parse_arg *yarg);
43
44 struct ynl_policy_attr {
45 enum ynl_policy_type type;
46 unsigned int len;
47 const char *name;
48 const struct ynl_policy_nest *nest;
49 };
50
51 struct ynl_policy_nest {
52 unsigned int max_attr;
53 const struct ynl_policy_attr *table;
54 };
55
56 struct ynl_parse_arg {
57 struct ynl_sock *ys;
58 const struct ynl_policy_nest *rsp_policy;
59 void *data;
60 };
61
62 struct ynl_dump_list_type {
63 struct ynl_dump_list_type *next;
64 unsigned char data[] __attribute__((aligned(8)));
65 };
66 extern struct ynl_dump_list_type *YNL_LIST_END;
67
ynl_dump_obj_is_last(void * obj)68 static inline bool ynl_dump_obj_is_last(void *obj)
69 {
70 unsigned long uptr = (unsigned long)obj;
71
72 uptr -= offsetof(struct ynl_dump_list_type, data);
73 return uptr == (unsigned long)YNL_LIST_END;
74 }
75
ynl_dump_obj_next(void * obj)76 static inline void *ynl_dump_obj_next(void *obj)
77 {
78 unsigned long uptr = (unsigned long)obj;
79 struct ynl_dump_list_type *list;
80
81 uptr -= offsetof(struct ynl_dump_list_type, data);
82 list = (struct ynl_dump_list_type *)uptr;
83 uptr = (unsigned long)list->next;
84 uptr += offsetof(struct ynl_dump_list_type, data);
85
86 return (void *)uptr;
87 }
88
89 struct ynl_ntf_base_type {
90 __u16 family;
91 __u8 cmd;
92 struct ynl_ntf_base_type *next;
93 void (*free)(struct ynl_ntf_base_type *ntf);
94 unsigned char data[] __attribute__((aligned(8)));
95 };
96
97 struct nlmsghdr *
98 ynl_gemsg_start_req(struct ynl_sock *ys, __u32 id, __u8 cmd, __u8 version);
99 struct nlmsghdr *
100 ynl_gemsg_start_dump(struct ynl_sock *ys, __u32 id, __u8 cmd, __u8 version);
101
102 int ynl_attr_validate(struct ynl_parse_arg *yarg, const struct nlattr *attr);
103
104 /* YNL specific helpers used by the auto-generated code */
105
106 struct ynl_req_state {
107 struct ynl_parse_arg yarg;
108 ynl_parse_cb_t cb;
109 __u32 rsp_cmd;
110 };
111
112 struct ynl_dump_state {
113 struct ynl_parse_arg yarg;
114 void *first;
115 struct ynl_dump_list_type *last;
116 size_t alloc_sz;
117 ynl_parse_cb_t cb;
118 __u32 rsp_cmd;
119 };
120
121 struct ynl_ntf_info {
122 const struct ynl_policy_nest *policy;
123 ynl_parse_cb_t cb;
124 size_t alloc_sz;
125 void (*free)(struct ynl_ntf_base_type *ntf);
126 };
127
128 int ynl_exec(struct ynl_sock *ys, struct nlmsghdr *req_nlh,
129 struct ynl_req_state *yrs);
130 int ynl_exec_dump(struct ynl_sock *ys, struct nlmsghdr *req_nlh,
131 struct ynl_dump_state *yds);
132
133 void ynl_error_unknown_notification(struct ynl_sock *ys, __u8 cmd);
134 int ynl_error_parse(struct ynl_parse_arg *yarg, const char *msg);
135
136 /* Netlink message handling helpers */
137
138 #define YNL_MSG_OVERFLOW 1
139
ynl_nlmsg_put_header(void * buf)140 static inline struct nlmsghdr *ynl_nlmsg_put_header(void *buf)
141 {
142 struct nlmsghdr *nlh = (struct nlmsghdr *)buf;
143
144 memset(nlh, 0, sizeof(*nlh));
145 nlh->nlmsg_len = NLMSG_HDRLEN;
146
147 return nlh;
148 }
149
ynl_nlmsg_data_len(const struct nlmsghdr * nlh)150 static inline unsigned int ynl_nlmsg_data_len(const struct nlmsghdr *nlh)
151 {
152 return nlh->nlmsg_len - NLMSG_HDRLEN;
153 }
154
ynl_nlmsg_data(const struct nlmsghdr * nlh)155 static inline void *ynl_nlmsg_data(const struct nlmsghdr *nlh)
156 {
157 return (unsigned char *)nlh + NLMSG_HDRLEN;
158 }
159
160 static inline void *
ynl_nlmsg_data_offset(const struct nlmsghdr * nlh,unsigned int offset)161 ynl_nlmsg_data_offset(const struct nlmsghdr *nlh, unsigned int offset)
162 {
163 return (unsigned char *)nlh + NLMSG_HDRLEN + offset;
164 }
165
ynl_nlmsg_end_addr(const struct nlmsghdr * nlh)166 static inline void *ynl_nlmsg_end_addr(const struct nlmsghdr *nlh)
167 {
168 return (char *)nlh + nlh->nlmsg_len;
169 }
170
171 static inline void *
ynl_nlmsg_put_extra_header(struct nlmsghdr * nlh,unsigned int size)172 ynl_nlmsg_put_extra_header(struct nlmsghdr *nlh, unsigned int size)
173 {
174 void *tail = ynl_nlmsg_end_addr(nlh);
175
176 nlh->nlmsg_len += NLMSG_ALIGN(size);
177 return tail;
178 }
179
180 /* Netlink attribute helpers */
181
ynl_attr_type(const struct nlattr * attr)182 static inline unsigned int ynl_attr_type(const struct nlattr *attr)
183 {
184 return attr->nla_type & NLA_TYPE_MASK;
185 }
186
ynl_attr_data_len(const struct nlattr * attr)187 static inline unsigned int ynl_attr_data_len(const struct nlattr *attr)
188 {
189 return attr->nla_len - NLA_HDRLEN;
190 }
191
ynl_attr_data(const struct nlattr * attr)192 static inline void *ynl_attr_data(const struct nlattr *attr)
193 {
194 return (unsigned char *)attr + NLA_HDRLEN;
195 }
196
ynl_attr_data_end(const struct nlattr * attr)197 static inline void *ynl_attr_data_end(const struct nlattr *attr)
198 {
199 return (char *)ynl_attr_data(attr) + ynl_attr_data_len(attr);
200 }
201
202 #define ynl_attr_for_each(attr, nlh, fixed_hdr_sz) \
203 for ((attr) = ynl_attr_first(nlh, (nlh)->nlmsg_len, \
204 NLMSG_HDRLEN + fixed_hdr_sz); attr; \
205 (attr) = ynl_attr_next(ynl_nlmsg_end_addr(nlh), attr))
206
207 #define ynl_attr_for_each_nested(attr, outer) \
208 for ((attr) = ynl_attr_first(outer, outer->nla_len, \
209 sizeof(struct nlattr)); attr; \
210 (attr) = ynl_attr_next(ynl_attr_data_end(outer), attr))
211
212 #define ynl_attr_for_each_payload(start, len, attr) \
213 for ((attr) = ynl_attr_first(start, len, 0); attr; \
214 (attr) = ynl_attr_next(start + len, attr))
215
216 static inline struct nlattr *
ynl_attr_if_good(const void * end,struct nlattr * attr)217 ynl_attr_if_good(const void *end, struct nlattr *attr)
218 {
219 if (attr + 1 > (const struct nlattr *)end)
220 return NULL;
221 if (ynl_attr_data_end(attr) > end)
222 return NULL;
223 return attr;
224 }
225
226 static inline struct nlattr *
ynl_attr_next(const void * end,const struct nlattr * prev)227 ynl_attr_next(const void *end, const struct nlattr *prev)
228 {
229 struct nlattr *attr;
230
231 attr = (struct nlattr *)((char *)prev + NLA_ALIGN(prev->nla_len));
232 return ynl_attr_if_good(end, attr);
233 }
234
235 static inline struct nlattr *
ynl_attr_first(const void * start,size_t len,size_t skip)236 ynl_attr_first(const void *start, size_t len, size_t skip)
237 {
238 struct nlattr *attr;
239
240 attr = (struct nlattr *)((char *)start + NLMSG_ALIGN(skip));
241 return ynl_attr_if_good((char *)start + len, attr);
242 }
243
244 static inline bool
__ynl_attr_put_overflow(struct nlmsghdr * nlh,size_t size)245 __ynl_attr_put_overflow(struct nlmsghdr *nlh, size_t size)
246 {
247 bool o;
248
249 /* ynl_msg_start() stashed buffer length in nlmsg_pid. */
250 o = nlh->nlmsg_len + NLA_HDRLEN + NLMSG_ALIGN(size) > nlh->nlmsg_pid;
251 if (o)
252 /* YNL_MSG_OVERFLOW is < NLMSG_HDRLEN, all subsequent checks
253 * are guaranteed to fail.
254 */
255 nlh->nlmsg_pid = YNL_MSG_OVERFLOW;
256 return o;
257 }
258
259 static inline struct nlattr *
ynl_attr_nest_start(struct nlmsghdr * nlh,unsigned int attr_type)260 ynl_attr_nest_start(struct nlmsghdr *nlh, unsigned int attr_type)
261 {
262 struct nlattr *attr;
263
264 if (__ynl_attr_put_overflow(nlh, 0))
265 return (struct nlattr *)ynl_nlmsg_end_addr(nlh) - 1;
266
267 attr = (struct nlattr *)ynl_nlmsg_end_addr(nlh);
268 attr->nla_type = attr_type | NLA_F_NESTED;
269 nlh->nlmsg_len += NLA_HDRLEN;
270
271 return attr;
272 }
273
274 static inline void
ynl_attr_nest_end(struct nlmsghdr * nlh,struct nlattr * attr)275 ynl_attr_nest_end(struct nlmsghdr *nlh, struct nlattr *attr)
276 {
277 attr->nla_len = (char *)ynl_nlmsg_end_addr(nlh) - (char *)attr;
278 }
279
280 static inline void
ynl_attr_put(struct nlmsghdr * nlh,unsigned int attr_type,const void * value,size_t size)281 ynl_attr_put(struct nlmsghdr *nlh, unsigned int attr_type,
282 const void *value, size_t size)
283 {
284 struct nlattr *attr;
285
286 if (__ynl_attr_put_overflow(nlh, size))
287 return;
288
289 attr = (struct nlattr *)ynl_nlmsg_end_addr(nlh);
290 attr->nla_type = attr_type;
291 attr->nla_len = NLA_HDRLEN + size;
292
293 memcpy(ynl_attr_data(attr), value, size);
294
295 nlh->nlmsg_len += NLMSG_ALIGN(attr->nla_len);
296 }
297
298 static inline void
ynl_attr_put_str(struct nlmsghdr * nlh,unsigned int attr_type,const char * str)299 ynl_attr_put_str(struct nlmsghdr *nlh, unsigned int attr_type, const char *str)
300 {
301 struct nlattr *attr;
302 size_t len;
303
304 len = strlen(str);
305 if (__ynl_attr_put_overflow(nlh, len))
306 return;
307
308 attr = (struct nlattr *)ynl_nlmsg_end_addr(nlh);
309 attr->nla_type = attr_type;
310
311 strcpy((char *)ynl_attr_data(attr), str);
312 attr->nla_len = NLA_HDRLEN + NLA_ALIGN(len);
313
314 nlh->nlmsg_len += NLMSG_ALIGN(attr->nla_len);
315 }
316
ynl_attr_get_str(const struct nlattr * attr)317 static inline const char *ynl_attr_get_str(const struct nlattr *attr)
318 {
319 return (const char *)ynl_attr_data(attr);
320 }
321
ynl_attr_get_s8(const struct nlattr * attr)322 static inline __s8 ynl_attr_get_s8(const struct nlattr *attr)
323 {
324 return *(__s8 *)ynl_attr_data(attr);
325 }
326
ynl_attr_get_s16(const struct nlattr * attr)327 static inline __s16 ynl_attr_get_s16(const struct nlattr *attr)
328 {
329 return *(__s16 *)ynl_attr_data(attr);
330 }
331
ynl_attr_get_s32(const struct nlattr * attr)332 static inline __s32 ynl_attr_get_s32(const struct nlattr *attr)
333 {
334 return *(__s32 *)ynl_attr_data(attr);
335 }
336
ynl_attr_get_s64(const struct nlattr * attr)337 static inline __s64 ynl_attr_get_s64(const struct nlattr *attr)
338 {
339 __s64 tmp;
340
341 memcpy(&tmp, (unsigned char *)(attr + 1), sizeof(tmp));
342 return tmp;
343 }
344
ynl_attr_get_u8(const struct nlattr * attr)345 static inline __u8 ynl_attr_get_u8(const struct nlattr *attr)
346 {
347 return *(__u8 *)ynl_attr_data(attr);
348 }
349
ynl_attr_get_u16(const struct nlattr * attr)350 static inline __u16 ynl_attr_get_u16(const struct nlattr *attr)
351 {
352 return *(__u16 *)ynl_attr_data(attr);
353 }
354
ynl_attr_get_u32(const struct nlattr * attr)355 static inline __u32 ynl_attr_get_u32(const struct nlattr *attr)
356 {
357 return *(__u32 *)ynl_attr_data(attr);
358 }
359
ynl_attr_get_u64(const struct nlattr * attr)360 static inline __u64 ynl_attr_get_u64(const struct nlattr *attr)
361 {
362 __u64 tmp;
363
364 memcpy(&tmp, (unsigned char *)(attr + 1), sizeof(tmp));
365 return tmp;
366 }
367
368 static inline void
ynl_attr_put_s8(struct nlmsghdr * nlh,unsigned int attr_type,__s8 value)369 ynl_attr_put_s8(struct nlmsghdr *nlh, unsigned int attr_type, __s8 value)
370 {
371 ynl_attr_put(nlh, attr_type, &value, sizeof(value));
372 }
373
374 static inline void
ynl_attr_put_s16(struct nlmsghdr * nlh,unsigned int attr_type,__s16 value)375 ynl_attr_put_s16(struct nlmsghdr *nlh, unsigned int attr_type, __s16 value)
376 {
377 ynl_attr_put(nlh, attr_type, &value, sizeof(value));
378 }
379
380 static inline void
ynl_attr_put_s32(struct nlmsghdr * nlh,unsigned int attr_type,__s32 value)381 ynl_attr_put_s32(struct nlmsghdr *nlh, unsigned int attr_type, __s32 value)
382 {
383 ynl_attr_put(nlh, attr_type, &value, sizeof(value));
384 }
385
386 static inline void
ynl_attr_put_s64(struct nlmsghdr * nlh,unsigned int attr_type,__s64 value)387 ynl_attr_put_s64(struct nlmsghdr *nlh, unsigned int attr_type, __s64 value)
388 {
389 ynl_attr_put(nlh, attr_type, &value, sizeof(value));
390 }
391
392 static inline void
ynl_attr_put_u8(struct nlmsghdr * nlh,unsigned int attr_type,__u8 value)393 ynl_attr_put_u8(struct nlmsghdr *nlh, unsigned int attr_type, __u8 value)
394 {
395 ynl_attr_put(nlh, attr_type, &value, sizeof(value));
396 }
397
398 static inline void
ynl_attr_put_u16(struct nlmsghdr * nlh,unsigned int attr_type,__u16 value)399 ynl_attr_put_u16(struct nlmsghdr *nlh, unsigned int attr_type, __u16 value)
400 {
401 ynl_attr_put(nlh, attr_type, &value, sizeof(value));
402 }
403
404 static inline void
ynl_attr_put_u32(struct nlmsghdr * nlh,unsigned int attr_type,__u32 value)405 ynl_attr_put_u32(struct nlmsghdr *nlh, unsigned int attr_type, __u32 value)
406 {
407 ynl_attr_put(nlh, attr_type, &value, sizeof(value));
408 }
409
410 static inline void
ynl_attr_put_u64(struct nlmsghdr * nlh,unsigned int attr_type,__u64 value)411 ynl_attr_put_u64(struct nlmsghdr *nlh, unsigned int attr_type, __u64 value)
412 {
413 ynl_attr_put(nlh, attr_type, &value, sizeof(value));
414 }
415
ynl_attr_get_uint(const struct nlattr * attr)416 static inline __u64 ynl_attr_get_uint(const struct nlattr *attr)
417 {
418 switch (ynl_attr_data_len(attr)) {
419 case 4:
420 return ynl_attr_get_u32(attr);
421 case 8:
422 return ynl_attr_get_u64(attr);
423 default:
424 return 0;
425 }
426 }
427
ynl_attr_get_sint(const struct nlattr * attr)428 static inline __s64 ynl_attr_get_sint(const struct nlattr *attr)
429 {
430 switch (ynl_attr_data_len(attr)) {
431 case 4:
432 return ynl_attr_get_s32(attr);
433 case 8:
434 return ynl_attr_get_s64(attr);
435 default:
436 return 0;
437 }
438 }
439
440 static inline void
ynl_attr_put_uint(struct nlmsghdr * nlh,__u16 type,__u64 data)441 ynl_attr_put_uint(struct nlmsghdr *nlh, __u16 type, __u64 data)
442 {
443 if ((__u32)data == (__u64)data)
444 ynl_attr_put_u32(nlh, type, data);
445 else
446 ynl_attr_put_u64(nlh, type, data);
447 }
448
449 static inline void
ynl_attr_put_sint(struct nlmsghdr * nlh,__u16 type,__s64 data)450 ynl_attr_put_sint(struct nlmsghdr *nlh, __u16 type, __s64 data)
451 {
452 if ((__s32)data == (__s64)data)
453 ynl_attr_put_s32(nlh, type, data);
454 else
455 ynl_attr_put_s64(nlh, type, data);
456 }
457 #endif
458