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 struct ynl_policy_nest *nest; 49 }; 50 51 struct ynl_policy_nest { 52 unsigned int max_attr; 53 struct ynl_policy_attr *table; 54 }; 55 56 struct ynl_parse_arg { 57 struct ynl_sock *ys; 58 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 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 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 = (void *)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 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 1 139 140 static inline struct nlmsghdr *ynl_nlmsg_put_header(void *buf) 141 { 142 struct nlmsghdr *nlh = buf; 143 144 memset(nlh, 0, sizeof(*nlh)); 145 nlh->nlmsg_len = NLMSG_HDRLEN; 146 147 return nlh; 148 } 149 150 static inline unsigned int ynl_nlmsg_data_len(const struct nlmsghdr *nlh) 151 { 152 return nlh->nlmsg_len - NLMSG_HDRLEN; 153 } 154 155 static inline void *ynl_nlmsg_data(const struct nlmsghdr *nlh) 156 { 157 return (unsigned char *)nlh + NLMSG_HDRLEN; 158 } 159 160 static inline void * 161 ynl_nlmsg_data_offset(const struct nlmsghdr *nlh, unsigned int offset) 162 { 163 return (unsigned char *)nlh + NLMSG_HDRLEN + offset; 164 } 165 166 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 * 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 */ 181 182 static inline unsigned int ynl_attr_type(const struct nlattr *attr) 183 { 184 return attr->nla_type & NLA_TYPE_MASK; 185 } 186 187 static inline unsigned int ynl_attr_data_len(const struct nlattr *attr) 188 { 189 return attr->nla_len - NLA_HDRLEN; 190 } 191 192 static inline void *ynl_attr_data(const struct nlattr *attr) 193 { 194 return (unsigned char *)attr + NLA_HDRLEN; 195 } 196 197 static inline void *ynl_attr_data_end(const struct nlattr *attr) 198 { 199 return 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 * 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 * 227 ynl_attr_next(const void *end, const struct nlattr *prev) 228 { 229 struct nlattr *attr; 230 231 attr = (void *)((char *)prev + NLA_ALIGN(prev->nla_len)); 232 return ynl_attr_if_good(end, attr); 233 } 234 235 static inline struct nlattr * 236 ynl_attr_first(const void *start, size_t len, size_t skip) 237 { 238 struct nlattr *attr; 239 240 attr = (void *)((char *)start + NLMSG_ALIGN(skip)); 241 return ynl_attr_if_good(start + len, attr); 242 } 243 244 static inline bool 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 * 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 ynl_nlmsg_end_addr(nlh) - NLA_HDRLEN; 266 267 attr = 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 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 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 = 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 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 = ynl_nlmsg_end_addr(nlh); 309 attr->nla_type = attr_type; 310 311 strcpy(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 } 316 317 static inline const char *ynl_attr_get_str(const struct nlattr *attr) 318 { 319 return (const char *)ynl_attr_data(attr); 320 } 321 322 static inline __s8 ynl_attr_get_s8(const struct nlattr *attr) 323 { 324 return *(__s8 *)ynl_attr_data(attr); 325 } 326 327 static inline __s16 ynl_attr_get_s16(const struct nlattr *attr) 328 { 329 return *(__s16 *)ynl_attr_data(attr); 330 } 331 332 static inline __s32 ynl_attr_get_s32(const struct nlattr *attr) 333 { 334 return *(__s32 *)ynl_attr_data(attr); 335 } 336 337 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 } 344 345 static inline __u8 ynl_attr_get_u8(const struct nlattr *attr) 346 { 347 return *(__u8 *)ynl_attr_data(attr); 348 } 349 350 static inline __u16 ynl_attr_get_u16(const struct nlattr *attr) 351 { 352 return *(__u16 *)ynl_attr_data(attr); 353 } 354 355 static inline __u32 ynl_attr_get_u32(const struct nlattr *attr) 356 { 357 return *(__u32 *)ynl_attr_data(attr); 358 } 359 360 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 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 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 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 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 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 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 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 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 } 415 416 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 } 427 428 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 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 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