1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __NET_NETLINK_H 3 #define __NET_NETLINK_H 4 5 #include <linux/types.h> 6 #include <linux/netlink.h> 7 #include <linux/jiffies.h> 8 #include <linux/in6.h> 9 10 /* ======================================================================== 11 * Netlink Messages and Attributes Interface (As Seen On TV) 12 * ------------------------------------------------------------------------ 13 * Messages Interface 14 * ------------------------------------------------------------------------ 15 * 16 * Message Format: 17 * <--- nlmsg_total_size(payload) ---> 18 * <-- nlmsg_msg_size(payload) -> 19 * +----------+- - -+-------------+- - -+-------- - - 20 * | nlmsghdr | Pad | Payload | Pad | nlmsghdr 21 * +----------+- - -+-------------+- - -+-------- - - 22 * nlmsg_data(nlh)---^ ^ 23 * nlmsg_next(nlh)-----------------------+ 24 * 25 * Payload Format: 26 * <---------------------- nlmsg_len(nlh) ---------------------> 27 * <------ hdrlen ------> <- nlmsg_attrlen(nlh, hdrlen) -> 28 * +----------------------+- - -+--------------------------------+ 29 * | Family Header | Pad | Attributes | 30 * +----------------------+- - -+--------------------------------+ 31 * nlmsg_attrdata(nlh, hdrlen)---^ 32 * 33 * Data Structures: 34 * struct nlmsghdr netlink message header 35 * 36 * Message Construction: 37 * nlmsg_new() create a new netlink message 38 * nlmsg_put() add a netlink message to an skb 39 * nlmsg_put_answer() callback based nlmsg_put() 40 * nlmsg_end() finalize netlink message 41 * nlmsg_get_pos() return current position in message 42 * nlmsg_trim() trim part of message 43 * nlmsg_cancel() cancel message construction 44 * nlmsg_consume() free a netlink message (expected) 45 * nlmsg_free() free a netlink message (drop) 46 * 47 * Message Sending: 48 * nlmsg_multicast() multicast message to several groups 49 * nlmsg_unicast() unicast a message to a single socket 50 * nlmsg_notify() send notification message 51 * 52 * Message Length Calculations: 53 * nlmsg_msg_size(payload) length of message w/o padding 54 * nlmsg_total_size(payload) length of message w/ padding 55 * nlmsg_padlen(payload) length of padding at tail 56 * 57 * Message Payload Access: 58 * nlmsg_data(nlh) head of message payload 59 * nlmsg_len(nlh) length of message payload 60 * nlmsg_attrdata(nlh, hdrlen) head of attributes data 61 * nlmsg_attrlen(nlh, hdrlen) length of attributes data 62 * 63 * Message Parsing: 64 * nlmsg_ok(nlh, remaining) does nlh fit into remaining bytes? 65 * nlmsg_next(nlh, remaining) get next netlink message 66 * nlmsg_parse() parse attributes of a message 67 * nlmsg_find_attr() find an attribute in a message 68 * nlmsg_for_each_msg() loop over all messages 69 * nlmsg_validate() validate netlink message incl. attrs 70 * nlmsg_for_each_attr() loop over all attributes 71 * 72 * Misc: 73 * nlmsg_report() report back to application? 74 * 75 * ------------------------------------------------------------------------ 76 * Attributes Interface 77 * ------------------------------------------------------------------------ 78 * 79 * Attribute Format: 80 * <------- nla_total_size(payload) -------> 81 * <---- nla_attr_size(payload) -----> 82 * +----------+- - -+- - - - - - - - - +- - -+-------- - - 83 * | Header | Pad | Payload | Pad | Header 84 * +----------+- - -+- - - - - - - - - +- - -+-------- - - 85 * <- nla_len(nla) -> ^ 86 * nla_data(nla)----^ | 87 * nla_next(nla)-----------------------------' 88 * 89 * Data Structures: 90 * struct nlattr netlink attribute header 91 * 92 * Attribute Construction: 93 * nla_reserve(skb, type, len) reserve room for an attribute 94 * nla_reserve_nohdr(skb, len) reserve room for an attribute w/o hdr 95 * nla_put(skb, type, len, data) add attribute to skb 96 * nla_put_nohdr(skb, len, data) add attribute w/o hdr 97 * nla_append(skb, len, data) append data to skb 98 * 99 * Attribute Construction for Basic Types: 100 * nla_put_u8(skb, type, value) add u8 attribute to skb 101 * nla_put_u16(skb, type, value) add u16 attribute to skb 102 * nla_put_u32(skb, type, value) add u32 attribute to skb 103 * nla_put_u64_64bit(skb, type, 104 * value, padattr) add u64 attribute to skb 105 * nla_put_s8(skb, type, value) add s8 attribute to skb 106 * nla_put_s16(skb, type, value) add s16 attribute to skb 107 * nla_put_s32(skb, type, value) add s32 attribute to skb 108 * nla_put_s64(skb, type, value, 109 * padattr) add s64 attribute to skb 110 * nla_put_string(skb, type, str) add string attribute to skb 111 * nla_put_flag(skb, type) add flag attribute to skb 112 * nla_put_msecs(skb, type, jiffies, 113 * padattr) add msecs attribute to skb 114 * nla_put_in_addr(skb, type, addr) add IPv4 address attribute to skb 115 * nla_put_in6_addr(skb, type, addr) add IPv6 address attribute to skb 116 * 117 * Nested Attributes Construction: 118 * nla_nest_start(skb, type) start a nested attribute 119 * nla_nest_end(skb, nla) finalize a nested attribute 120 * nla_nest_cancel(skb, nla) cancel nested attribute construction 121 * 122 * Attribute Length Calculations: 123 * nla_attr_size(payload) length of attribute w/o padding 124 * nla_total_size(payload) length of attribute w/ padding 125 * nla_padlen(payload) length of padding 126 * 127 * Attribute Payload Access: 128 * nla_data(nla) head of attribute payload 129 * nla_len(nla) length of attribute payload 130 * 131 * Attribute Payload Access for Basic Types: 132 * nla_get_uint(nla) get payload for a uint attribute 133 * nla_get_sint(nla) get payload for a sint attribute 134 * nla_get_u8(nla) get payload for a u8 attribute 135 * nla_get_u16(nla) get payload for a u16 attribute 136 * nla_get_u32(nla) get payload for a u32 attribute 137 * nla_get_u64(nla) get payload for a u64 attribute 138 * nla_get_s8(nla) get payload for a s8 attribute 139 * nla_get_s16(nla) get payload for a s16 attribute 140 * nla_get_s32(nla) get payload for a s32 attribute 141 * nla_get_s64(nla) get payload for a s64 attribute 142 * nla_get_flag(nla) return 1 if flag is true 143 * nla_get_msecs(nla) get payload for a msecs attribute 144 * 145 * The same functions also exist with _default(). 146 * 147 * Attribute Misc: 148 * nla_memcpy(dest, nla, count) copy attribute into memory 149 * nla_memcmp(nla, data, size) compare attribute with memory area 150 * nla_strscpy(dst, nla, size) copy attribute to a sized string 151 * nla_strcmp(nla, str) compare attribute with string 152 * 153 * Attribute Parsing: 154 * nla_ok(nla, remaining) does nla fit into remaining bytes? 155 * nla_next(nla, remaining) get next netlink attribute 156 * nla_validate() validate a stream of attributes 157 * nla_validate_nested() validate a stream of nested attributes 158 * nla_find() find attribute in stream of attributes 159 * nla_find_nested() find attribute in nested attributes 160 * nla_parse() parse and validate stream of attrs 161 * nla_parse_nested() parse nested attributes 162 * nla_for_each_attr() loop over all attributes 163 * nla_for_each_attr_type() loop over all attributes with the 164 * given type 165 * nla_for_each_nested() loop over the nested attributes 166 * nla_for_each_nested_type() loop over the nested attributes with 167 * the given type 168 *========================================================================= 169 */ 170 171 /** 172 * Standard attribute types to specify validation policy 173 */ 174 enum { 175 NLA_UNSPEC, 176 NLA_U8, 177 NLA_U16, 178 NLA_U32, 179 NLA_U64, 180 NLA_STRING, 181 NLA_FLAG, 182 NLA_MSECS, 183 NLA_NESTED, 184 NLA_NESTED_ARRAY, 185 NLA_NUL_STRING, 186 NLA_BINARY, 187 NLA_S8, 188 NLA_S16, 189 NLA_S32, 190 NLA_S64, 191 NLA_BITFIELD32, 192 NLA_REJECT, 193 NLA_BE16, 194 NLA_BE32, 195 NLA_SINT, 196 NLA_UINT, 197 __NLA_TYPE_MAX, 198 }; 199 200 #define NLA_TYPE_MAX (__NLA_TYPE_MAX - 1) 201 202 struct netlink_range_validation { 203 u64 min, max; 204 }; 205 206 struct netlink_range_validation_signed { 207 s64 min, max; 208 }; 209 210 enum nla_policy_validation { 211 NLA_VALIDATE_NONE, 212 NLA_VALIDATE_RANGE, 213 NLA_VALIDATE_RANGE_WARN_TOO_LONG, 214 NLA_VALIDATE_MIN, 215 NLA_VALIDATE_MAX, 216 NLA_VALIDATE_MASK, 217 NLA_VALIDATE_RANGE_PTR, 218 NLA_VALIDATE_FUNCTION, 219 }; 220 221 /** 222 * struct nla_policy - attribute validation policy 223 * @type: Type of attribute or NLA_UNSPEC 224 * @validation_type: type of attribute validation done in addition to 225 * type-specific validation (e.g. range, function call), see 226 * &enum nla_policy_validation 227 * @len: Type specific length of payload 228 * 229 * Policies are defined as arrays of this struct, the array must be 230 * accessible by attribute type up to the highest identifier to be expected. 231 * 232 * Meaning of `len' field: 233 * NLA_STRING Maximum length of string 234 * NLA_NUL_STRING Maximum length of string (excluding NUL) 235 * NLA_FLAG Unused 236 * NLA_BINARY Maximum length of attribute payload 237 * (but see also below with the validation type) 238 * NLA_NESTED, 239 * NLA_NESTED_ARRAY Length verification is done by checking len of 240 * nested header (or empty); len field is used if 241 * nested_policy is also used, for the max attr 242 * number in the nested policy. 243 * NLA_SINT, NLA_UINT, 244 * NLA_U8, NLA_U16, 245 * NLA_U32, NLA_U64, 246 * NLA_S8, NLA_S16, 247 * NLA_S32, NLA_S64, 248 * NLA_BE16, NLA_BE32, 249 * NLA_MSECS Leaving the length field zero will verify the 250 * given type fits, using it verifies minimum length 251 * just like "All other" 252 * NLA_BITFIELD32 Unused 253 * NLA_REJECT Unused 254 * All other Minimum length of attribute payload 255 * 256 * Meaning of validation union: 257 * NLA_BITFIELD32 This is a 32-bit bitmap/bitselector attribute and 258 * `bitfield32_valid' is the u32 value of valid flags 259 * NLA_REJECT This attribute is always rejected and `reject_message' 260 * may point to a string to report as the error instead 261 * of the generic one in extended ACK. 262 * NLA_NESTED `nested_policy' to a nested policy to validate, must 263 * also set `len' to the max attribute number. Use the 264 * provided NLA_POLICY_NESTED() macro. 265 * Note that nla_parse() will validate, but of course not 266 * parse, the nested sub-policies. 267 * NLA_NESTED_ARRAY `nested_policy' points to a nested policy to validate, 268 * must also set `len' to the max attribute number. Use 269 * the provided NLA_POLICY_NESTED_ARRAY() macro. 270 * The difference to NLA_NESTED is the structure: 271 * NLA_NESTED has the nested attributes directly inside 272 * while an array has the nested attributes at another 273 * level down and the attribute types directly in the 274 * nesting don't matter. 275 * NLA_UINT, 276 * NLA_U8, 277 * NLA_U16, 278 * NLA_U32, 279 * NLA_U64, 280 * NLA_BE16, 281 * NLA_BE32, 282 * NLA_SINT, 283 * NLA_S8, 284 * NLA_S16, 285 * NLA_S32, 286 * NLA_S64 The `min' and `max' fields are used depending on the 287 * validation_type field, if that is min/max/range then 288 * the min, max or both are used (respectively) to check 289 * the value of the integer attribute. 290 * Note that in the interest of code simplicity and 291 * struct size both limits are s16, so you cannot 292 * enforce a range that doesn't fall within the range 293 * of s16 - do that using the NLA_POLICY_FULL_RANGE() 294 * or NLA_POLICY_FULL_RANGE_SIGNED() macros instead. 295 * Use the NLA_POLICY_MIN(), NLA_POLICY_MAX() and 296 * NLA_POLICY_RANGE() macros. 297 * NLA_UINT, 298 * NLA_U8, 299 * NLA_U16, 300 * NLA_U32, 301 * NLA_U64 If the validation_type field instead is set to 302 * NLA_VALIDATE_RANGE_PTR, `range' must be a pointer 303 * to a struct netlink_range_validation that indicates 304 * the min/max values. 305 * Use NLA_POLICY_FULL_RANGE(). 306 * NLA_SINT, 307 * NLA_S8, 308 * NLA_S16, 309 * NLA_S32, 310 * NLA_S64 If the validation_type field instead is set to 311 * NLA_VALIDATE_RANGE_PTR, `range_signed' must be a 312 * pointer to a struct netlink_range_validation_signed 313 * that indicates the min/max values. 314 * Use NLA_POLICY_FULL_RANGE_SIGNED(). 315 * 316 * NLA_BINARY If the validation type is like the ones for integers 317 * above, then the min/max length (not value like for 318 * integers) of the attribute is enforced. 319 * 320 * All other Unused - but note that it's a union 321 * 322 * Meaning of `validate' field, use via NLA_POLICY_VALIDATE_FN: 323 * NLA_BINARY Validation function called for the attribute. 324 * All other Unused - but note that it's a union 325 * 326 * Example: 327 * 328 * static const u32 myvalidflags = 0xff231023; 329 * 330 * static const struct nla_policy my_policy[ATTR_MAX+1] = { 331 * [ATTR_FOO] = { .type = NLA_U16 }, 332 * [ATTR_BAR] = { .type = NLA_STRING, .len = BARSIZ }, 333 * [ATTR_BAZ] = NLA_POLICY_EXACT_LEN(sizeof(struct mystruct)), 334 * [ATTR_GOO] = NLA_POLICY_BITFIELD32(myvalidflags), 335 * }; 336 */ 337 struct nla_policy { 338 u8 type; 339 u8 validation_type; 340 u16 len; 341 union { 342 /** 343 * @strict_start_type: first attribute to validate strictly 344 * 345 * This entry is special, and used for the attribute at index 0 346 * only, and specifies special data about the policy, namely it 347 * specifies the "boundary type" where strict length validation 348 * starts for any attribute types >= this value, also, strict 349 * nesting validation starts here. 350 * 351 * Additionally, it means that NLA_UNSPEC is actually NLA_REJECT 352 * for any types >= this, so need to use NLA_POLICY_MIN_LEN() to 353 * get the previous pure { .len = xyz } behaviour. The advantage 354 * of this is that types not specified in the policy will be 355 * rejected. 356 * 357 * For completely new families it should be set to 1 so that the 358 * validation is enforced for all attributes. For existing ones 359 * it should be set at least when new attributes are added to 360 * the enum used by the policy, and be set to the new value that 361 * was added to enforce strict validation from thereon. 362 */ 363 u16 strict_start_type; 364 365 /* private: use NLA_POLICY_*() to set */ 366 const u32 bitfield32_valid; 367 const u32 mask; 368 const char *reject_message; 369 const struct nla_policy *nested_policy; 370 const struct netlink_range_validation *range; 371 const struct netlink_range_validation_signed *range_signed; 372 struct { 373 s16 min, max; 374 }; 375 int (*validate)(const struct nlattr *attr, 376 struct netlink_ext_ack *extack); 377 }; 378 }; 379 380 #define NLA_POLICY_ETH_ADDR NLA_POLICY_EXACT_LEN(ETH_ALEN) 381 #define NLA_POLICY_ETH_ADDR_COMPAT NLA_POLICY_EXACT_LEN_WARN(ETH_ALEN) 382 383 #define _NLA_POLICY_NESTED(maxattr, policy) \ 384 { .type = NLA_NESTED, .nested_policy = policy, .len = maxattr } 385 #define _NLA_POLICY_NESTED_ARRAY(maxattr, policy) \ 386 { .type = NLA_NESTED_ARRAY, .nested_policy = policy, .len = maxattr } 387 #define NLA_POLICY_NESTED(policy) \ 388 _NLA_POLICY_NESTED(ARRAY_SIZE(policy) - 1, policy) 389 #define NLA_POLICY_NESTED_ARRAY(policy) \ 390 _NLA_POLICY_NESTED_ARRAY(ARRAY_SIZE(policy) - 1, policy) 391 #define NLA_POLICY_BITFIELD32(valid) \ 392 { .type = NLA_BITFIELD32, .bitfield32_valid = valid } 393 394 #define __NLA_IS_UINT_TYPE(tp) \ 395 (tp == NLA_U8 || tp == NLA_U16 || tp == NLA_U32 || \ 396 tp == NLA_U64 || tp == NLA_UINT || \ 397 tp == NLA_BE16 || tp == NLA_BE32) 398 #define __NLA_IS_SINT_TYPE(tp) \ 399 (tp == NLA_S8 || tp == NLA_S16 || tp == NLA_S32 || tp == NLA_S64 || \ 400 tp == NLA_SINT) 401 402 #define __NLA_ENSURE(condition) BUILD_BUG_ON_ZERO(!(condition)) 403 #define NLA_ENSURE_UINT_TYPE(tp) \ 404 (__NLA_ENSURE(__NLA_IS_UINT_TYPE(tp)) + tp) 405 #define NLA_ENSURE_UINT_OR_BINARY_TYPE(tp) \ 406 (__NLA_ENSURE(__NLA_IS_UINT_TYPE(tp) || \ 407 tp == NLA_MSECS || \ 408 tp == NLA_BINARY) + tp) 409 #define NLA_ENSURE_SINT_TYPE(tp) \ 410 (__NLA_ENSURE(__NLA_IS_SINT_TYPE(tp)) + tp) 411 #define NLA_ENSURE_INT_OR_BINARY_TYPE(tp) \ 412 (__NLA_ENSURE(__NLA_IS_UINT_TYPE(tp) || \ 413 __NLA_IS_SINT_TYPE(tp) || \ 414 tp == NLA_MSECS || \ 415 tp == NLA_BINARY) + tp) 416 #define NLA_ENSURE_NO_VALIDATION_PTR(tp) \ 417 (__NLA_ENSURE(tp != NLA_BITFIELD32 && \ 418 tp != NLA_REJECT && \ 419 tp != NLA_NESTED && \ 420 tp != NLA_NESTED_ARRAY) + tp) 421 422 #define NLA_POLICY_RANGE(tp, _min, _max) { \ 423 .type = NLA_ENSURE_INT_OR_BINARY_TYPE(tp), \ 424 .validation_type = NLA_VALIDATE_RANGE, \ 425 .min = _min, \ 426 .max = _max \ 427 } 428 429 #define NLA_POLICY_FULL_RANGE(tp, _range) { \ 430 .type = NLA_ENSURE_UINT_OR_BINARY_TYPE(tp), \ 431 .validation_type = NLA_VALIDATE_RANGE_PTR, \ 432 .range = _range, \ 433 } 434 435 #define NLA_POLICY_FULL_RANGE_SIGNED(tp, _range) { \ 436 .type = NLA_ENSURE_SINT_TYPE(tp), \ 437 .validation_type = NLA_VALIDATE_RANGE_PTR, \ 438 .range_signed = _range, \ 439 } 440 441 #define NLA_POLICY_MIN(tp, _min) { \ 442 .type = NLA_ENSURE_INT_OR_BINARY_TYPE(tp), \ 443 .validation_type = NLA_VALIDATE_MIN, \ 444 .min = _min, \ 445 } 446 447 #define NLA_POLICY_MAX(tp, _max) { \ 448 .type = NLA_ENSURE_INT_OR_BINARY_TYPE(tp), \ 449 .validation_type = NLA_VALIDATE_MAX, \ 450 .max = _max, \ 451 } 452 453 #define NLA_POLICY_MASK(tp, _mask) { \ 454 .type = NLA_ENSURE_UINT_TYPE(tp), \ 455 .validation_type = NLA_VALIDATE_MASK, \ 456 .mask = _mask, \ 457 } 458 459 #define NLA_POLICY_VALIDATE_FN(tp, fn, ...) { \ 460 .type = NLA_ENSURE_NO_VALIDATION_PTR(tp), \ 461 .validation_type = NLA_VALIDATE_FUNCTION, \ 462 .validate = fn, \ 463 .len = __VA_ARGS__ + 0, \ 464 } 465 466 #define NLA_POLICY_EXACT_LEN(_len) NLA_POLICY_RANGE(NLA_BINARY, _len, _len) 467 #define NLA_POLICY_EXACT_LEN_WARN(_len) { \ 468 .type = NLA_BINARY, \ 469 .validation_type = NLA_VALIDATE_RANGE_WARN_TOO_LONG, \ 470 .min = _len, \ 471 .max = _len \ 472 } 473 #define NLA_POLICY_MIN_LEN(_len) NLA_POLICY_MIN(NLA_BINARY, _len) 474 #define NLA_POLICY_MAX_LEN(_len) NLA_POLICY_MAX(NLA_BINARY, _len) 475 476 /** 477 * struct nl_info - netlink source information 478 * @nlh: Netlink message header of original request 479 * @nl_net: Network namespace 480 * @portid: Netlink PORTID of requesting application 481 * @skip_notify: Skip netlink notifications to user space 482 * @skip_notify_kernel: Skip selected in-kernel notifications 483 */ 484 struct nl_info { 485 struct nlmsghdr *nlh; 486 struct net *nl_net; 487 u32 portid; 488 u8 skip_notify:1, 489 skip_notify_kernel:1; 490 }; 491 492 /** 493 * enum netlink_validation - netlink message/attribute validation levels 494 * @NL_VALIDATE_LIBERAL: Old-style "be liberal" validation, not caring about 495 * extra data at the end of the message, attributes being longer than 496 * they should be, or unknown attributes being present. 497 * @NL_VALIDATE_TRAILING: Reject junk data encountered after attribute parsing. 498 * @NL_VALIDATE_MAXTYPE: Reject attributes > max type; Together with _TRAILING 499 * this is equivalent to the old nla_parse_strict()/nlmsg_parse_strict(). 500 * @NL_VALIDATE_UNSPEC: Reject attributes with NLA_UNSPEC in the policy. 501 * This can safely be set by the kernel when the given policy has no 502 * NLA_UNSPEC anymore, and can thus be used to ensure policy entries 503 * are enforced going forward. 504 * @NL_VALIDATE_STRICT_ATTRS: strict attribute policy parsing (e.g. 505 * U8, U16, U32 must have exact size, etc.) 506 * @NL_VALIDATE_NESTED: Check that NLA_F_NESTED is set for NLA_NESTED(_ARRAY) 507 * and unset for other policies. 508 */ 509 enum netlink_validation { 510 NL_VALIDATE_LIBERAL = 0, 511 NL_VALIDATE_TRAILING = BIT(0), 512 NL_VALIDATE_MAXTYPE = BIT(1), 513 NL_VALIDATE_UNSPEC = BIT(2), 514 NL_VALIDATE_STRICT_ATTRS = BIT(3), 515 NL_VALIDATE_NESTED = BIT(4), 516 }; 517 518 #define NL_VALIDATE_DEPRECATED_STRICT (NL_VALIDATE_TRAILING |\ 519 NL_VALIDATE_MAXTYPE) 520 #define NL_VALIDATE_STRICT (NL_VALIDATE_TRAILING |\ 521 NL_VALIDATE_MAXTYPE |\ 522 NL_VALIDATE_UNSPEC |\ 523 NL_VALIDATE_STRICT_ATTRS |\ 524 NL_VALIDATE_NESTED) 525 526 int netlink_rcv_skb(struct sk_buff *skb, 527 int (*cb)(struct sk_buff *, struct nlmsghdr *, 528 struct netlink_ext_ack *)); 529 int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 portid, 530 unsigned int group, int report, gfp_t flags); 531 532 int __nla_validate(const struct nlattr *head, int len, int maxtype, 533 const struct nla_policy *policy, unsigned int validate, 534 struct netlink_ext_ack *extack); 535 int __nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head, 536 int len, const struct nla_policy *policy, unsigned int validate, 537 struct netlink_ext_ack *extack); 538 int nla_policy_len(const struct nla_policy *, int); 539 struct nlattr *nla_find(const struct nlattr *head, int len, int attrtype); 540 ssize_t nla_strscpy(char *dst, const struct nlattr *nla, size_t dstsize); 541 char *nla_strdup(const struct nlattr *nla, gfp_t flags); 542 int nla_memcpy(void *dest, const struct nlattr *src, int count); 543 int nla_memcmp(const struct nlattr *nla, const void *data, size_t size); 544 int nla_strcmp(const struct nlattr *nla, const char *str); 545 struct nlattr *__nla_reserve(struct sk_buff *skb, int attrtype, int attrlen); 546 struct nlattr *__nla_reserve_64bit(struct sk_buff *skb, int attrtype, 547 int attrlen, int padattr); 548 void *__nla_reserve_nohdr(struct sk_buff *skb, int attrlen); 549 struct nlattr *nla_reserve(struct sk_buff *skb, int attrtype, int attrlen); 550 struct nlattr *nla_reserve_64bit(struct sk_buff *skb, int attrtype, 551 int attrlen, int padattr); 552 void *nla_reserve_nohdr(struct sk_buff *skb, int attrlen); 553 void __nla_put(struct sk_buff *skb, int attrtype, int attrlen, 554 const void *data); 555 void __nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen, 556 const void *data, int padattr); 557 void __nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data); 558 int nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data); 559 int nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen, 560 const void *data, int padattr); 561 int nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data); 562 int nla_append(struct sk_buff *skb, int attrlen, const void *data); 563 564 /************************************************************************** 565 * Netlink Messages 566 **************************************************************************/ 567 568 /** 569 * nlmsg_msg_size - length of netlink message not including padding 570 * @payload: length of message payload 571 */ 572 static inline int nlmsg_msg_size(int payload) 573 { 574 return NLMSG_HDRLEN + payload; 575 } 576 577 /** 578 * nlmsg_total_size - length of netlink message including padding 579 * @payload: length of message payload 580 */ 581 static inline int nlmsg_total_size(int payload) 582 { 583 return NLMSG_ALIGN(nlmsg_msg_size(payload)); 584 } 585 586 /** 587 * nlmsg_padlen - length of padding at the message's tail 588 * @payload: length of message payload 589 */ 590 static inline int nlmsg_padlen(int payload) 591 { 592 return nlmsg_total_size(payload) - nlmsg_msg_size(payload); 593 } 594 595 /** 596 * nlmsg_data - head of message payload 597 * @nlh: netlink message header 598 */ 599 static inline void *nlmsg_data(const struct nlmsghdr *nlh) 600 { 601 return (unsigned char *) nlh + NLMSG_HDRLEN; 602 } 603 604 /** 605 * nlmsg_len - length of message payload 606 * @nlh: netlink message header 607 */ 608 static inline int nlmsg_len(const struct nlmsghdr *nlh) 609 { 610 return nlh->nlmsg_len - NLMSG_HDRLEN; 611 } 612 613 /** 614 * nlmsg_attrdata - head of attributes data 615 * @nlh: netlink message header 616 * @hdrlen: length of family specific header 617 */ 618 static inline struct nlattr *nlmsg_attrdata(const struct nlmsghdr *nlh, 619 int hdrlen) 620 { 621 unsigned char *data = nlmsg_data(nlh); 622 return (struct nlattr *) (data + NLMSG_ALIGN(hdrlen)); 623 } 624 625 /** 626 * nlmsg_attrlen - length of attributes data 627 * @nlh: netlink message header 628 * @hdrlen: length of family specific header 629 */ 630 static inline int nlmsg_attrlen(const struct nlmsghdr *nlh, int hdrlen) 631 { 632 return nlmsg_len(nlh) - NLMSG_ALIGN(hdrlen); 633 } 634 635 /** 636 * nlmsg_ok - check if the netlink message fits into the remaining bytes 637 * @nlh: netlink message header 638 * @remaining: number of bytes remaining in message stream 639 */ 640 static inline int nlmsg_ok(const struct nlmsghdr *nlh, int remaining) 641 { 642 return (remaining >= (int) sizeof(struct nlmsghdr) && 643 nlh->nlmsg_len >= sizeof(struct nlmsghdr) && 644 nlh->nlmsg_len <= remaining); 645 } 646 647 /** 648 * nlmsg_next - next netlink message in message stream 649 * @nlh: netlink message header 650 * @remaining: number of bytes remaining in message stream 651 * 652 * Returns the next netlink message in the message stream and 653 * decrements remaining by the size of the current message. 654 */ 655 static inline struct nlmsghdr * 656 nlmsg_next(const struct nlmsghdr *nlh, int *remaining) 657 { 658 int totlen = NLMSG_ALIGN(nlh->nlmsg_len); 659 660 *remaining -= totlen; 661 662 return (struct nlmsghdr *) ((unsigned char *) nlh + totlen); 663 } 664 665 /** 666 * nla_parse - Parse a stream of attributes into a tb buffer 667 * @tb: destination array with maxtype+1 elements 668 * @maxtype: maximum attribute type to be expected 669 * @head: head of attribute stream 670 * @len: length of attribute stream 671 * @policy: validation policy 672 * @extack: extended ACK pointer 673 * 674 * Parses a stream of attributes and stores a pointer to each attribute in 675 * the tb array accessible via the attribute type. Attributes with a type 676 * exceeding maxtype will be rejected, policy must be specified, attributes 677 * will be validated in the strictest way possible. 678 * 679 * Returns 0 on success or a negative error code. 680 */ 681 static inline int nla_parse(struct nlattr **tb, int maxtype, 682 const struct nlattr *head, int len, 683 const struct nla_policy *policy, 684 struct netlink_ext_ack *extack) 685 { 686 return __nla_parse(tb, maxtype, head, len, policy, 687 NL_VALIDATE_STRICT, extack); 688 } 689 690 /** 691 * nla_parse_deprecated - Parse a stream of attributes into a tb buffer 692 * @tb: destination array with maxtype+1 elements 693 * @maxtype: maximum attribute type to be expected 694 * @head: head of attribute stream 695 * @len: length of attribute stream 696 * @policy: validation policy 697 * @extack: extended ACK pointer 698 * 699 * Parses a stream of attributes and stores a pointer to each attribute in 700 * the tb array accessible via the attribute type. Attributes with a type 701 * exceeding maxtype will be ignored and attributes from the policy are not 702 * always strictly validated (only for new attributes). 703 * 704 * Returns 0 on success or a negative error code. 705 */ 706 static inline int nla_parse_deprecated(struct nlattr **tb, int maxtype, 707 const struct nlattr *head, int len, 708 const struct nla_policy *policy, 709 struct netlink_ext_ack *extack) 710 { 711 return __nla_parse(tb, maxtype, head, len, policy, 712 NL_VALIDATE_LIBERAL, extack); 713 } 714 715 /** 716 * nla_parse_deprecated_strict - Parse a stream of attributes into a tb buffer 717 * @tb: destination array with maxtype+1 elements 718 * @maxtype: maximum attribute type to be expected 719 * @head: head of attribute stream 720 * @len: length of attribute stream 721 * @policy: validation policy 722 * @extack: extended ACK pointer 723 * 724 * Parses a stream of attributes and stores a pointer to each attribute in 725 * the tb array accessible via the attribute type. Attributes with a type 726 * exceeding maxtype will be rejected as well as trailing data, but the 727 * policy is not completely strictly validated (only for new attributes). 728 * 729 * Returns 0 on success or a negative error code. 730 */ 731 static inline int nla_parse_deprecated_strict(struct nlattr **tb, int maxtype, 732 const struct nlattr *head, 733 int len, 734 const struct nla_policy *policy, 735 struct netlink_ext_ack *extack) 736 { 737 return __nla_parse(tb, maxtype, head, len, policy, 738 NL_VALIDATE_DEPRECATED_STRICT, extack); 739 } 740 741 /** 742 * __nlmsg_parse - parse attributes of a netlink message 743 * @nlh: netlink message header 744 * @hdrlen: length of family specific header 745 * @tb: destination array with maxtype+1 elements 746 * @maxtype: maximum attribute type to be expected 747 * @policy: validation policy 748 * @validate: validation strictness 749 * @extack: extended ACK report struct 750 * 751 * See nla_parse() 752 */ 753 static inline int __nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen, 754 struct nlattr *tb[], int maxtype, 755 const struct nla_policy *policy, 756 unsigned int validate, 757 struct netlink_ext_ack *extack) 758 { 759 if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) { 760 NL_SET_ERR_MSG(extack, "Invalid header length"); 761 return -EINVAL; 762 } 763 764 return __nla_parse(tb, maxtype, nlmsg_attrdata(nlh, hdrlen), 765 nlmsg_attrlen(nlh, hdrlen), policy, validate, 766 extack); 767 } 768 769 /** 770 * nlmsg_parse - parse attributes of a netlink message 771 * @nlh: netlink message header 772 * @hdrlen: length of family specific header 773 * @tb: destination array with maxtype+1 elements 774 * @maxtype: maximum attribute type to be expected 775 * @policy: validation policy 776 * @extack: extended ACK report struct 777 * 778 * See nla_parse() 779 */ 780 static inline int nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen, 781 struct nlattr *tb[], int maxtype, 782 const struct nla_policy *policy, 783 struct netlink_ext_ack *extack) 784 { 785 return __nlmsg_parse(nlh, hdrlen, tb, maxtype, policy, 786 NL_VALIDATE_STRICT, extack); 787 } 788 789 /** 790 * nlmsg_parse_deprecated - parse attributes of a netlink message 791 * @nlh: netlink message header 792 * @hdrlen: length of family specific header 793 * @tb: destination array with maxtype+1 elements 794 * @maxtype: maximum attribute type to be expected 795 * @policy: validation policy 796 * @extack: extended ACK report struct 797 * 798 * See nla_parse_deprecated() 799 */ 800 static inline int nlmsg_parse_deprecated(const struct nlmsghdr *nlh, int hdrlen, 801 struct nlattr *tb[], int maxtype, 802 const struct nla_policy *policy, 803 struct netlink_ext_ack *extack) 804 { 805 return __nlmsg_parse(nlh, hdrlen, tb, maxtype, policy, 806 NL_VALIDATE_LIBERAL, extack); 807 } 808 809 /** 810 * nlmsg_parse_deprecated_strict - parse attributes of a netlink message 811 * @nlh: netlink message header 812 * @hdrlen: length of family specific header 813 * @tb: destination array with maxtype+1 elements 814 * @maxtype: maximum attribute type to be expected 815 * @policy: validation policy 816 * @extack: extended ACK report struct 817 * 818 * See nla_parse_deprecated_strict() 819 */ 820 static inline int 821 nlmsg_parse_deprecated_strict(const struct nlmsghdr *nlh, int hdrlen, 822 struct nlattr *tb[], int maxtype, 823 const struct nla_policy *policy, 824 struct netlink_ext_ack *extack) 825 { 826 return __nlmsg_parse(nlh, hdrlen, tb, maxtype, policy, 827 NL_VALIDATE_DEPRECATED_STRICT, extack); 828 } 829 830 /** 831 * nlmsg_find_attr - find a specific attribute in a netlink message 832 * @nlh: netlink message header 833 * @hdrlen: length of family specific header 834 * @attrtype: type of attribute to look for 835 * 836 * Returns the first attribute which matches the specified type. 837 */ 838 static inline struct nlattr *nlmsg_find_attr(const struct nlmsghdr *nlh, 839 int hdrlen, int attrtype) 840 { 841 return nla_find(nlmsg_attrdata(nlh, hdrlen), 842 nlmsg_attrlen(nlh, hdrlen), attrtype); 843 } 844 845 /** 846 * nla_validate_deprecated - Validate a stream of attributes 847 * @head: head of attribute stream 848 * @len: length of attribute stream 849 * @maxtype: maximum attribute type to be expected 850 * @policy: validation policy 851 * @extack: extended ACK report struct 852 * 853 * Validates all attributes in the specified attribute stream against the 854 * specified policy. Validation is done in liberal mode. 855 * See documentation of struct nla_policy for more details. 856 * 857 * Returns 0 on success or a negative error code. 858 */ 859 static inline int nla_validate_deprecated(const struct nlattr *head, int len, 860 int maxtype, 861 const struct nla_policy *policy, 862 struct netlink_ext_ack *extack) 863 { 864 return __nla_validate(head, len, maxtype, policy, NL_VALIDATE_LIBERAL, 865 extack); 866 } 867 868 /** 869 * nla_validate - Validate a stream of attributes 870 * @head: head of attribute stream 871 * @len: length of attribute stream 872 * @maxtype: maximum attribute type to be expected 873 * @policy: validation policy 874 * @extack: extended ACK report struct 875 * 876 * Validates all attributes in the specified attribute stream against the 877 * specified policy. Validation is done in strict mode. 878 * See documentation of struct nla_policy for more details. 879 * 880 * Returns 0 on success or a negative error code. 881 */ 882 static inline int nla_validate(const struct nlattr *head, int len, int maxtype, 883 const struct nla_policy *policy, 884 struct netlink_ext_ack *extack) 885 { 886 return __nla_validate(head, len, maxtype, policy, NL_VALIDATE_STRICT, 887 extack); 888 } 889 890 /** 891 * nlmsg_validate_deprecated - validate a netlink message including attributes 892 * @nlh: netlinket message header 893 * @hdrlen: length of family specific header 894 * @maxtype: maximum attribute type to be expected 895 * @policy: validation policy 896 * @extack: extended ACK report struct 897 */ 898 static inline int nlmsg_validate_deprecated(const struct nlmsghdr *nlh, 899 int hdrlen, int maxtype, 900 const struct nla_policy *policy, 901 struct netlink_ext_ack *extack) 902 { 903 if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) 904 return -EINVAL; 905 906 return __nla_validate(nlmsg_attrdata(nlh, hdrlen), 907 nlmsg_attrlen(nlh, hdrlen), maxtype, 908 policy, NL_VALIDATE_LIBERAL, extack); 909 } 910 911 912 913 /** 914 * nlmsg_report - need to report back to application? 915 * @nlh: netlink message header 916 * 917 * Returns 1 if a report back to the application is requested. 918 */ 919 static inline int nlmsg_report(const struct nlmsghdr *nlh) 920 { 921 return nlh ? !!(nlh->nlmsg_flags & NLM_F_ECHO) : 0; 922 } 923 924 /** 925 * nlmsg_seq - return the seq number of netlink message 926 * @nlh: netlink message header 927 * 928 * Returns 0 if netlink message is NULL 929 */ 930 static inline u32 nlmsg_seq(const struct nlmsghdr *nlh) 931 { 932 return nlh ? nlh->nlmsg_seq : 0; 933 } 934 935 /** 936 * nlmsg_for_each_attr - iterate over a stream of attributes 937 * @pos: loop counter, set to current attribute 938 * @nlh: netlink message header 939 * @hdrlen: length of family specific header 940 * @rem: initialized to len, holds bytes currently remaining in stream 941 */ 942 #define nlmsg_for_each_attr(pos, nlh, hdrlen, rem) \ 943 nla_for_each_attr(pos, nlmsg_attrdata(nlh, hdrlen), \ 944 nlmsg_attrlen(nlh, hdrlen), rem) 945 946 /** 947 * nlmsg_put - Add a new netlink message to an skb 948 * @skb: socket buffer to store message in 949 * @portid: netlink PORTID of requesting application 950 * @seq: sequence number of message 951 * @type: message type 952 * @payload: length of message payload 953 * @flags: message flags 954 * 955 * Returns NULL if the tailroom of the skb is insufficient to store 956 * the message header and payload. 957 */ 958 static inline struct nlmsghdr *nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, 959 int type, int payload, int flags) 960 { 961 if (unlikely(skb_tailroom(skb) < nlmsg_total_size(payload))) 962 return NULL; 963 964 return __nlmsg_put(skb, portid, seq, type, payload, flags); 965 } 966 967 /** 968 * nlmsg_append - Add more data to a nlmsg in a skb 969 * @skb: socket buffer to store message in 970 * @size: length of message payload 971 * 972 * Append data to an existing nlmsg, used when constructing a message 973 * with multiple fixed-format headers (which is rare). 974 * Returns NULL if the tailroom of the skb is insufficient to store 975 * the extra payload. 976 */ 977 static inline void *nlmsg_append(struct sk_buff *skb, u32 size) 978 { 979 if (unlikely(skb_tailroom(skb) < NLMSG_ALIGN(size))) 980 return NULL; 981 982 if (NLMSG_ALIGN(size) - size) 983 memset(skb_tail_pointer(skb) + size, 0, 984 NLMSG_ALIGN(size) - size); 985 return __skb_put(skb, NLMSG_ALIGN(size)); 986 } 987 988 /** 989 * nlmsg_put_answer - Add a new callback based netlink message to an skb 990 * @skb: socket buffer to store message in 991 * @cb: netlink callback 992 * @type: message type 993 * @payload: length of message payload 994 * @flags: message flags 995 * 996 * Returns NULL if the tailroom of the skb is insufficient to store 997 * the message header and payload. 998 */ 999 static inline struct nlmsghdr *nlmsg_put_answer(struct sk_buff *skb, 1000 struct netlink_callback *cb, 1001 int type, int payload, 1002 int flags) 1003 { 1004 return nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, 1005 type, payload, flags); 1006 } 1007 1008 /** 1009 * nlmsg_new - Allocate a new netlink message 1010 * @payload: size of the message payload 1011 * @flags: the type of memory to allocate. 1012 * 1013 * Use NLMSG_DEFAULT_SIZE if the size of the payload isn't known 1014 * and a good default is needed. 1015 */ 1016 static inline struct sk_buff *nlmsg_new(size_t payload, gfp_t flags) 1017 { 1018 return alloc_skb(nlmsg_total_size(payload), flags); 1019 } 1020 1021 /** 1022 * nlmsg_new_large - Allocate a new netlink message with non-contiguous 1023 * physical memory 1024 * @payload: size of the message payload 1025 * 1026 * The allocated skb is unable to have frag page for shinfo->frags*, 1027 * as the NULL setting for skb->head in netlink_skb_destructor() will 1028 * bypass most of the handling in skb_release_data() 1029 */ 1030 static inline struct sk_buff *nlmsg_new_large(size_t payload) 1031 { 1032 return netlink_alloc_large_skb(nlmsg_total_size(payload), 0); 1033 } 1034 1035 /** 1036 * nlmsg_end - Finalize a netlink message 1037 * @skb: socket buffer the message is stored in 1038 * @nlh: netlink message header 1039 * 1040 * Corrects the netlink message header to include the appended 1041 * attributes. Only necessary if attributes have been added to 1042 * the message. 1043 */ 1044 static inline void nlmsg_end(struct sk_buff *skb, struct nlmsghdr *nlh) 1045 { 1046 nlh->nlmsg_len = skb_tail_pointer(skb) - (unsigned char *)nlh; 1047 } 1048 1049 /** 1050 * nlmsg_get_pos - return current position in netlink message 1051 * @skb: socket buffer the message is stored in 1052 * 1053 * Returns a pointer to the current tail of the message. 1054 */ 1055 static inline void *nlmsg_get_pos(struct sk_buff *skb) 1056 { 1057 return skb_tail_pointer(skb); 1058 } 1059 1060 /** 1061 * nlmsg_trim - Trim message to a mark 1062 * @skb: socket buffer the message is stored in 1063 * @mark: mark to trim to 1064 * 1065 * Trims the message to the provided mark. 1066 */ 1067 static inline void nlmsg_trim(struct sk_buff *skb, const void *mark) 1068 { 1069 if (mark) { 1070 WARN_ON((unsigned char *) mark < skb->data); 1071 skb_trim(skb, (unsigned char *) mark - skb->data); 1072 } 1073 } 1074 1075 /** 1076 * nlmsg_cancel - Cancel construction of a netlink message 1077 * @skb: socket buffer the message is stored in 1078 * @nlh: netlink message header 1079 * 1080 * Removes the complete netlink message including all 1081 * attributes from the socket buffer again. 1082 */ 1083 static inline void nlmsg_cancel(struct sk_buff *skb, struct nlmsghdr *nlh) 1084 { 1085 nlmsg_trim(skb, nlh); 1086 } 1087 1088 /** 1089 * nlmsg_free - drop a netlink message 1090 * @skb: socket buffer of netlink message 1091 */ 1092 static inline void nlmsg_free(struct sk_buff *skb) 1093 { 1094 kfree_skb(skb); 1095 } 1096 1097 /** 1098 * nlmsg_consume - free a netlink message 1099 * @skb: socket buffer of netlink message 1100 */ 1101 static inline void nlmsg_consume(struct sk_buff *skb) 1102 { 1103 consume_skb(skb); 1104 } 1105 1106 /** 1107 * nlmsg_multicast_filtered - multicast a netlink message with filter function 1108 * @sk: netlink socket to spread messages to 1109 * @skb: netlink message as socket buffer 1110 * @portid: own netlink portid to avoid sending to yourself 1111 * @group: multicast group id 1112 * @flags: allocation flags 1113 * @filter: filter function 1114 * @filter_data: filter function private data 1115 * 1116 * Return: 0 on success, negative error code for failure. 1117 */ 1118 static inline int nlmsg_multicast_filtered(struct sock *sk, struct sk_buff *skb, 1119 u32 portid, unsigned int group, 1120 gfp_t flags, 1121 netlink_filter_fn filter, 1122 void *filter_data) 1123 { 1124 int err; 1125 1126 NETLINK_CB(skb).dst_group = group; 1127 1128 err = netlink_broadcast_filtered(sk, skb, portid, group, flags, 1129 filter, filter_data); 1130 if (err > 0) 1131 err = 0; 1132 1133 return err; 1134 } 1135 1136 /** 1137 * nlmsg_multicast - multicast a netlink message 1138 * @sk: netlink socket to spread messages to 1139 * @skb: netlink message as socket buffer 1140 * @portid: own netlink portid to avoid sending to yourself 1141 * @group: multicast group id 1142 * @flags: allocation flags 1143 */ 1144 static inline int nlmsg_multicast(struct sock *sk, struct sk_buff *skb, 1145 u32 portid, unsigned int group, gfp_t flags) 1146 { 1147 return nlmsg_multicast_filtered(sk, skb, portid, group, flags, 1148 NULL, NULL); 1149 } 1150 1151 /** 1152 * nlmsg_unicast - unicast a netlink message 1153 * @sk: netlink socket to spread message to 1154 * @skb: netlink message as socket buffer 1155 * @portid: netlink portid of the destination socket 1156 */ 1157 static inline int nlmsg_unicast(struct sock *sk, struct sk_buff *skb, u32 portid) 1158 { 1159 int err; 1160 1161 err = netlink_unicast(sk, skb, portid, MSG_DONTWAIT); 1162 if (err > 0) 1163 err = 0; 1164 1165 return err; 1166 } 1167 1168 /** 1169 * nlmsg_for_each_msg - iterate over a stream of messages 1170 * @pos: loop counter, set to current message 1171 * @head: head of message stream 1172 * @len: length of message stream 1173 * @rem: initialized to len, holds bytes currently remaining in stream 1174 */ 1175 #define nlmsg_for_each_msg(pos, head, len, rem) \ 1176 for (pos = head, rem = len; \ 1177 nlmsg_ok(pos, rem); \ 1178 pos = nlmsg_next(pos, &(rem))) 1179 1180 /** 1181 * nl_dump_check_consistent - check if sequence is consistent and advertise if not 1182 * @cb: netlink callback structure that stores the sequence number 1183 * @nlh: netlink message header to write the flag to 1184 * 1185 * This function checks if the sequence (generation) number changed during dump 1186 * and if it did, advertises it in the netlink message header. 1187 * 1188 * The correct way to use it is to set cb->seq to the generation counter when 1189 * all locks for dumping have been acquired, and then call this function for 1190 * each message that is generated. 1191 * 1192 * Note that due to initialisation concerns, 0 is an invalid sequence number 1193 * and must not be used by code that uses this functionality. 1194 */ 1195 static inline void 1196 nl_dump_check_consistent(struct netlink_callback *cb, 1197 struct nlmsghdr *nlh) 1198 { 1199 if (cb->prev_seq && cb->seq != cb->prev_seq) 1200 nlh->nlmsg_flags |= NLM_F_DUMP_INTR; 1201 cb->prev_seq = cb->seq; 1202 } 1203 1204 /************************************************************************** 1205 * Netlink Attributes 1206 **************************************************************************/ 1207 1208 /** 1209 * nla_attr_size - length of attribute not including padding 1210 * @payload: length of payload 1211 */ 1212 static inline int nla_attr_size(int payload) 1213 { 1214 return NLA_HDRLEN + payload; 1215 } 1216 1217 /** 1218 * nla_total_size - total length of attribute including padding 1219 * @payload: length of payload 1220 */ 1221 static inline int nla_total_size(int payload) 1222 { 1223 return NLA_ALIGN(nla_attr_size(payload)); 1224 } 1225 1226 /** 1227 * nla_padlen - length of padding at the tail of attribute 1228 * @payload: length of payload 1229 */ 1230 static inline int nla_padlen(int payload) 1231 { 1232 return nla_total_size(payload) - nla_attr_size(payload); 1233 } 1234 1235 /** 1236 * nla_type - attribute type 1237 * @nla: netlink attribute 1238 */ 1239 static inline int nla_type(const struct nlattr *nla) 1240 { 1241 return nla->nla_type & NLA_TYPE_MASK; 1242 } 1243 1244 /** 1245 * nla_data - head of payload 1246 * @nla: netlink attribute 1247 */ 1248 static inline void *nla_data(const struct nlattr *nla) 1249 { 1250 return (char *) nla + NLA_HDRLEN; 1251 } 1252 1253 /** 1254 * nla_len - length of payload 1255 * @nla: netlink attribute 1256 */ 1257 static inline u16 nla_len(const struct nlattr *nla) 1258 { 1259 return nla->nla_len - NLA_HDRLEN; 1260 } 1261 1262 /** 1263 * nla_ok - check if the netlink attribute fits into the remaining bytes 1264 * @nla: netlink attribute 1265 * @remaining: number of bytes remaining in attribute stream 1266 */ 1267 static inline int nla_ok(const struct nlattr *nla, int remaining) 1268 { 1269 return remaining >= (int) sizeof(*nla) && 1270 nla->nla_len >= sizeof(*nla) && 1271 nla->nla_len <= remaining; 1272 } 1273 1274 /** 1275 * nla_next - next netlink attribute in attribute stream 1276 * @nla: netlink attribute 1277 * @remaining: number of bytes remaining in attribute stream 1278 * 1279 * Returns the next netlink attribute in the attribute stream and 1280 * decrements remaining by the size of the current attribute. 1281 */ 1282 static inline struct nlattr *nla_next(const struct nlattr *nla, int *remaining) 1283 { 1284 unsigned int totlen = NLA_ALIGN(nla->nla_len); 1285 1286 *remaining -= totlen; 1287 return (struct nlattr *) ((char *) nla + totlen); 1288 } 1289 1290 /** 1291 * nla_find_nested - find attribute in a set of nested attributes 1292 * @nla: attribute containing the nested attributes 1293 * @attrtype: type of attribute to look for 1294 * 1295 * Returns the first attribute which matches the specified type. 1296 */ 1297 static inline struct nlattr * 1298 nla_find_nested(const struct nlattr *nla, int attrtype) 1299 { 1300 return nla_find(nla_data(nla), nla_len(nla), attrtype); 1301 } 1302 1303 /** 1304 * nla_parse_nested - parse nested attributes 1305 * @tb: destination array with maxtype+1 elements 1306 * @maxtype: maximum attribute type to be expected 1307 * @nla: attribute containing the nested attributes 1308 * @policy: validation policy 1309 * @extack: extended ACK report struct 1310 * 1311 * See nla_parse() 1312 */ 1313 static inline int nla_parse_nested(struct nlattr *tb[], int maxtype, 1314 const struct nlattr *nla, 1315 const struct nla_policy *policy, 1316 struct netlink_ext_ack *extack) 1317 { 1318 if (!(nla->nla_type & NLA_F_NESTED)) { 1319 NL_SET_ERR_MSG_ATTR(extack, nla, "NLA_F_NESTED is missing"); 1320 return -EINVAL; 1321 } 1322 1323 return __nla_parse(tb, maxtype, nla_data(nla), nla_len(nla), policy, 1324 NL_VALIDATE_STRICT, extack); 1325 } 1326 1327 /** 1328 * nla_parse_nested_deprecated - parse nested attributes 1329 * @tb: destination array with maxtype+1 elements 1330 * @maxtype: maximum attribute type to be expected 1331 * @nla: attribute containing the nested attributes 1332 * @policy: validation policy 1333 * @extack: extended ACK report struct 1334 * 1335 * See nla_parse_deprecated() 1336 */ 1337 static inline int nla_parse_nested_deprecated(struct nlattr *tb[], int maxtype, 1338 const struct nlattr *nla, 1339 const struct nla_policy *policy, 1340 struct netlink_ext_ack *extack) 1341 { 1342 return __nla_parse(tb, maxtype, nla_data(nla), nla_len(nla), policy, 1343 NL_VALIDATE_LIBERAL, extack); 1344 } 1345 1346 /** 1347 * nla_put_u8 - Add a u8 netlink attribute to a socket buffer 1348 * @skb: socket buffer to add attribute to 1349 * @attrtype: attribute type 1350 * @value: numeric value 1351 */ 1352 static inline int nla_put_u8(struct sk_buff *skb, int attrtype, u8 value) 1353 { 1354 /* temporary variables to work around GCC PR81715 with asan-stack=1 */ 1355 u8 tmp = value; 1356 1357 return nla_put(skb, attrtype, sizeof(u8), &tmp); 1358 } 1359 1360 /** 1361 * nla_put_u16 - Add a u16 netlink attribute to a socket buffer 1362 * @skb: socket buffer to add attribute to 1363 * @attrtype: attribute type 1364 * @value: numeric value 1365 */ 1366 static inline int nla_put_u16(struct sk_buff *skb, int attrtype, u16 value) 1367 { 1368 u16 tmp = value; 1369 1370 return nla_put(skb, attrtype, sizeof(u16), &tmp); 1371 } 1372 1373 /** 1374 * nla_put_be16 - Add a __be16 netlink attribute to a socket buffer 1375 * @skb: socket buffer to add attribute to 1376 * @attrtype: attribute type 1377 * @value: numeric value 1378 */ 1379 static inline int nla_put_be16(struct sk_buff *skb, int attrtype, __be16 value) 1380 { 1381 __be16 tmp = value; 1382 1383 return nla_put(skb, attrtype, sizeof(__be16), &tmp); 1384 } 1385 1386 /** 1387 * nla_put_net16 - Add 16-bit network byte order netlink attribute to a socket buffer 1388 * @skb: socket buffer to add attribute to 1389 * @attrtype: attribute type 1390 * @value: numeric value 1391 */ 1392 static inline int nla_put_net16(struct sk_buff *skb, int attrtype, __be16 value) 1393 { 1394 __be16 tmp = value; 1395 1396 return nla_put_be16(skb, attrtype | NLA_F_NET_BYTEORDER, tmp); 1397 } 1398 1399 /** 1400 * nla_put_le16 - Add a __le16 netlink attribute to a socket buffer 1401 * @skb: socket buffer to add attribute to 1402 * @attrtype: attribute type 1403 * @value: numeric value 1404 */ 1405 static inline int nla_put_le16(struct sk_buff *skb, int attrtype, __le16 value) 1406 { 1407 __le16 tmp = value; 1408 1409 return nla_put(skb, attrtype, sizeof(__le16), &tmp); 1410 } 1411 1412 /** 1413 * nla_put_u32 - Add a u32 netlink attribute to a socket buffer 1414 * @skb: socket buffer to add attribute to 1415 * @attrtype: attribute type 1416 * @value: numeric value 1417 */ 1418 static inline int nla_put_u32(struct sk_buff *skb, int attrtype, u32 value) 1419 { 1420 u32 tmp = value; 1421 1422 return nla_put(skb, attrtype, sizeof(u32), &tmp); 1423 } 1424 1425 /** 1426 * nla_put_uint - Add a variable-size unsigned int to a socket buffer 1427 * @skb: socket buffer to add attribute to 1428 * @attrtype: attribute type 1429 * @value: numeric value 1430 */ 1431 static inline int nla_put_uint(struct sk_buff *skb, int attrtype, u64 value) 1432 { 1433 u64 tmp64 = value; 1434 u32 tmp32 = value; 1435 1436 if (tmp64 == tmp32) 1437 return nla_put_u32(skb, attrtype, tmp32); 1438 return nla_put(skb, attrtype, sizeof(u64), &tmp64); 1439 } 1440 1441 /** 1442 * nla_put_be32 - Add a __be32 netlink attribute to a socket buffer 1443 * @skb: socket buffer to add attribute to 1444 * @attrtype: attribute type 1445 * @value: numeric value 1446 */ 1447 static inline int nla_put_be32(struct sk_buff *skb, int attrtype, __be32 value) 1448 { 1449 __be32 tmp = value; 1450 1451 return nla_put(skb, attrtype, sizeof(__be32), &tmp); 1452 } 1453 1454 /** 1455 * nla_put_net32 - Add 32-bit network byte order netlink attribute to a socket buffer 1456 * @skb: socket buffer to add attribute to 1457 * @attrtype: attribute type 1458 * @value: numeric value 1459 */ 1460 static inline int nla_put_net32(struct sk_buff *skb, int attrtype, __be32 value) 1461 { 1462 __be32 tmp = value; 1463 1464 return nla_put_be32(skb, attrtype | NLA_F_NET_BYTEORDER, tmp); 1465 } 1466 1467 /** 1468 * nla_put_le32 - Add a __le32 netlink attribute to a socket buffer 1469 * @skb: socket buffer to add attribute to 1470 * @attrtype: attribute type 1471 * @value: numeric value 1472 */ 1473 static inline int nla_put_le32(struct sk_buff *skb, int attrtype, __le32 value) 1474 { 1475 __le32 tmp = value; 1476 1477 return nla_put(skb, attrtype, sizeof(__le32), &tmp); 1478 } 1479 1480 /** 1481 * nla_put_u64_64bit - Add a u64 netlink attribute to a skb and align it 1482 * @skb: socket buffer to add attribute to 1483 * @attrtype: attribute type 1484 * @value: numeric value 1485 * @padattr: attribute type for the padding 1486 */ 1487 static inline int nla_put_u64_64bit(struct sk_buff *skb, int attrtype, 1488 u64 value, int padattr) 1489 { 1490 u64 tmp = value; 1491 1492 return nla_put_64bit(skb, attrtype, sizeof(u64), &tmp, padattr); 1493 } 1494 1495 /** 1496 * nla_put_be64 - Add a __be64 netlink attribute to a socket buffer and align it 1497 * @skb: socket buffer to add attribute to 1498 * @attrtype: attribute type 1499 * @value: numeric value 1500 * @padattr: attribute type for the padding 1501 */ 1502 static inline int nla_put_be64(struct sk_buff *skb, int attrtype, __be64 value, 1503 int padattr) 1504 { 1505 __be64 tmp = value; 1506 1507 return nla_put_64bit(skb, attrtype, sizeof(__be64), &tmp, padattr); 1508 } 1509 1510 /** 1511 * nla_put_net64 - Add 64-bit network byte order nlattr to a skb and align it 1512 * @skb: socket buffer to add attribute to 1513 * @attrtype: attribute type 1514 * @value: numeric value 1515 * @padattr: attribute type for the padding 1516 */ 1517 static inline int nla_put_net64(struct sk_buff *skb, int attrtype, __be64 value, 1518 int padattr) 1519 { 1520 __be64 tmp = value; 1521 1522 return nla_put_be64(skb, attrtype | NLA_F_NET_BYTEORDER, tmp, 1523 padattr); 1524 } 1525 1526 /** 1527 * nla_put_le64 - Add a __le64 netlink attribute to a socket buffer and align it 1528 * @skb: socket buffer to add attribute to 1529 * @attrtype: attribute type 1530 * @value: numeric value 1531 * @padattr: attribute type for the padding 1532 */ 1533 static inline int nla_put_le64(struct sk_buff *skb, int attrtype, __le64 value, 1534 int padattr) 1535 { 1536 __le64 tmp = value; 1537 1538 return nla_put_64bit(skb, attrtype, sizeof(__le64), &tmp, padattr); 1539 } 1540 1541 /** 1542 * nla_put_s8 - Add a s8 netlink attribute to a socket buffer 1543 * @skb: socket buffer to add attribute to 1544 * @attrtype: attribute type 1545 * @value: numeric value 1546 */ 1547 static inline int nla_put_s8(struct sk_buff *skb, int attrtype, s8 value) 1548 { 1549 s8 tmp = value; 1550 1551 return nla_put(skb, attrtype, sizeof(s8), &tmp); 1552 } 1553 1554 /** 1555 * nla_put_s16 - Add a s16 netlink attribute to a socket buffer 1556 * @skb: socket buffer to add attribute to 1557 * @attrtype: attribute type 1558 * @value: numeric value 1559 */ 1560 static inline int nla_put_s16(struct sk_buff *skb, int attrtype, s16 value) 1561 { 1562 s16 tmp = value; 1563 1564 return nla_put(skb, attrtype, sizeof(s16), &tmp); 1565 } 1566 1567 /** 1568 * nla_put_s32 - Add a s32 netlink attribute to a socket buffer 1569 * @skb: socket buffer to add attribute to 1570 * @attrtype: attribute type 1571 * @value: numeric value 1572 */ 1573 static inline int nla_put_s32(struct sk_buff *skb, int attrtype, s32 value) 1574 { 1575 s32 tmp = value; 1576 1577 return nla_put(skb, attrtype, sizeof(s32), &tmp); 1578 } 1579 1580 /** 1581 * nla_put_s64 - Add a s64 netlink attribute to a socket buffer and align it 1582 * @skb: socket buffer to add attribute to 1583 * @attrtype: attribute type 1584 * @value: numeric value 1585 * @padattr: attribute type for the padding 1586 */ 1587 static inline int nla_put_s64(struct sk_buff *skb, int attrtype, s64 value, 1588 int padattr) 1589 { 1590 s64 tmp = value; 1591 1592 return nla_put_64bit(skb, attrtype, sizeof(s64), &tmp, padattr); 1593 } 1594 1595 /** 1596 * nla_put_sint - Add a variable-size signed int to a socket buffer 1597 * @skb: socket buffer to add attribute to 1598 * @attrtype: attribute type 1599 * @value: numeric value 1600 */ 1601 static inline int nla_put_sint(struct sk_buff *skb, int attrtype, s64 value) 1602 { 1603 s64 tmp64 = value; 1604 s32 tmp32 = value; 1605 1606 if (tmp64 == tmp32) 1607 return nla_put_s32(skb, attrtype, tmp32); 1608 return nla_put(skb, attrtype, sizeof(s64), &tmp64); 1609 } 1610 1611 /** 1612 * nla_put_string - Add a string netlink attribute to a socket buffer 1613 * @skb: socket buffer to add attribute to 1614 * @attrtype: attribute type 1615 * @str: NUL terminated string 1616 */ 1617 static inline int nla_put_string(struct sk_buff *skb, int attrtype, 1618 const char *str) 1619 { 1620 return nla_put(skb, attrtype, strlen(str) + 1, str); 1621 } 1622 1623 /** 1624 * nla_put_flag - Add a flag netlink attribute to a socket buffer 1625 * @skb: socket buffer to add attribute to 1626 * @attrtype: attribute type 1627 */ 1628 static inline int nla_put_flag(struct sk_buff *skb, int attrtype) 1629 { 1630 return nla_put(skb, attrtype, 0, NULL); 1631 } 1632 1633 /** 1634 * nla_put_msecs - Add a msecs netlink attribute to a skb and align it 1635 * @skb: socket buffer to add attribute to 1636 * @attrtype: attribute type 1637 * @njiffies: number of jiffies to convert to msecs 1638 * @padattr: attribute type for the padding 1639 */ 1640 static inline int nla_put_msecs(struct sk_buff *skb, int attrtype, 1641 unsigned long njiffies, int padattr) 1642 { 1643 u64 tmp = jiffies_to_msecs(njiffies); 1644 1645 return nla_put_64bit(skb, attrtype, sizeof(u64), &tmp, padattr); 1646 } 1647 1648 /** 1649 * nla_put_in_addr - Add an IPv4 address netlink attribute to a socket 1650 * buffer 1651 * @skb: socket buffer to add attribute to 1652 * @attrtype: attribute type 1653 * @addr: IPv4 address 1654 */ 1655 static inline int nla_put_in_addr(struct sk_buff *skb, int attrtype, 1656 __be32 addr) 1657 { 1658 __be32 tmp = addr; 1659 1660 return nla_put_be32(skb, attrtype, tmp); 1661 } 1662 1663 /** 1664 * nla_put_in6_addr - Add an IPv6 address netlink attribute to a socket 1665 * buffer 1666 * @skb: socket buffer to add attribute to 1667 * @attrtype: attribute type 1668 * @addr: IPv6 address 1669 */ 1670 static inline int nla_put_in6_addr(struct sk_buff *skb, int attrtype, 1671 const struct in6_addr *addr) 1672 { 1673 return nla_put(skb, attrtype, sizeof(*addr), addr); 1674 } 1675 1676 /** 1677 * nla_put_bitfield32 - Add a bitfield32 netlink attribute to a socket buffer 1678 * @skb: socket buffer to add attribute to 1679 * @attrtype: attribute type 1680 * @value: value carrying bits 1681 * @selector: selector of valid bits 1682 */ 1683 static inline int nla_put_bitfield32(struct sk_buff *skb, int attrtype, 1684 __u32 value, __u32 selector) 1685 { 1686 struct nla_bitfield32 tmp = { value, selector, }; 1687 1688 return nla_put(skb, attrtype, sizeof(tmp), &tmp); 1689 } 1690 1691 /** 1692 * nla_get_u32 - return payload of u32 attribute 1693 * @nla: u32 netlink attribute 1694 */ 1695 static inline u32 nla_get_u32(const struct nlattr *nla) 1696 { 1697 return *(u32 *) nla_data(nla); 1698 } 1699 1700 /** 1701 * nla_get_u32_default - return payload of u32 attribute or default 1702 * @nla: u32 netlink attribute, may be %NULL 1703 * @defvalue: default value to use if @nla is %NULL 1704 * 1705 * Return: the value of the attribute, or the default value if not present 1706 */ 1707 static inline u32 nla_get_u32_default(const struct nlattr *nla, u32 defvalue) 1708 { 1709 if (!nla) 1710 return defvalue; 1711 return nla_get_u32(nla); 1712 } 1713 1714 /** 1715 * nla_get_be32 - return payload of __be32 attribute 1716 * @nla: __be32 netlink attribute 1717 */ 1718 static inline __be32 nla_get_be32(const struct nlattr *nla) 1719 { 1720 return *(__be32 *) nla_data(nla); 1721 } 1722 1723 /** 1724 * nla_get_be32_default - return payload of be32 attribute or default 1725 * @nla: __be32 netlink attribute, may be %NULL 1726 * @defvalue: default value to use if @nla is %NULL 1727 * 1728 * Return: the value of the attribute, or the default value if not present 1729 */ 1730 static inline __be32 nla_get_be32_default(const struct nlattr *nla, 1731 __be32 defvalue) 1732 { 1733 if (!nla) 1734 return defvalue; 1735 return nla_get_be32(nla); 1736 } 1737 1738 /** 1739 * nla_get_le32 - return payload of __le32 attribute 1740 * @nla: __le32 netlink attribute 1741 */ 1742 static inline __le32 nla_get_le32(const struct nlattr *nla) 1743 { 1744 return *(__le32 *) nla_data(nla); 1745 } 1746 1747 /** 1748 * nla_get_le32_default - return payload of le32 attribute or default 1749 * @nla: __le32 netlink attribute, may be %NULL 1750 * @defvalue: default value to use if @nla is %NULL 1751 * 1752 * Return: the value of the attribute, or the default value if not present 1753 */ 1754 static inline __le32 nla_get_le32_default(const struct nlattr *nla, 1755 __le32 defvalue) 1756 { 1757 if (!nla) 1758 return defvalue; 1759 return nla_get_le32(nla); 1760 } 1761 1762 /** 1763 * nla_get_u16 - return payload of u16 attribute 1764 * @nla: u16 netlink attribute 1765 */ 1766 static inline u16 nla_get_u16(const struct nlattr *nla) 1767 { 1768 return *(u16 *) nla_data(nla); 1769 } 1770 1771 /** 1772 * nla_get_u16_default - return payload of u16 attribute or default 1773 * @nla: u16 netlink attribute, may be %NULL 1774 * @defvalue: default value to use if @nla is %NULL 1775 * 1776 * Return: the value of the attribute, or the default value if not present 1777 */ 1778 static inline u16 nla_get_u16_default(const struct nlattr *nla, u16 defvalue) 1779 { 1780 if (!nla) 1781 return defvalue; 1782 return nla_get_u16(nla); 1783 } 1784 1785 /** 1786 * nla_get_be16 - return payload of __be16 attribute 1787 * @nla: __be16 netlink attribute 1788 */ 1789 static inline __be16 nla_get_be16(const struct nlattr *nla) 1790 { 1791 return *(__be16 *) nla_data(nla); 1792 } 1793 1794 /** 1795 * nla_get_be16_default - return payload of be16 attribute or default 1796 * @nla: __be16 netlink attribute, may be %NULL 1797 * @defvalue: default value to use if @nla is %NULL 1798 * 1799 * Return: the value of the attribute, or the default value if not present 1800 */ 1801 static inline __be16 nla_get_be16_default(const struct nlattr *nla, 1802 __be16 defvalue) 1803 { 1804 if (!nla) 1805 return defvalue; 1806 return nla_get_be16(nla); 1807 } 1808 1809 /** 1810 * nla_get_le16 - return payload of __le16 attribute 1811 * @nla: __le16 netlink attribute 1812 */ 1813 static inline __le16 nla_get_le16(const struct nlattr *nla) 1814 { 1815 return *(__le16 *) nla_data(nla); 1816 } 1817 1818 /** 1819 * nla_get_le16_default - return payload of le16 attribute or default 1820 * @nla: __le16 netlink attribute, may be %NULL 1821 * @defvalue: default value to use if @nla is %NULL 1822 * 1823 * Return: the value of the attribute, or the default value if not present 1824 */ 1825 static inline __le16 nla_get_le16_default(const struct nlattr *nla, 1826 __le16 defvalue) 1827 { 1828 if (!nla) 1829 return defvalue; 1830 return nla_get_le16(nla); 1831 } 1832 1833 /** 1834 * nla_get_u8 - return payload of u8 attribute 1835 * @nla: u8 netlink attribute 1836 */ 1837 static inline u8 nla_get_u8(const struct nlattr *nla) 1838 { 1839 return *(u8 *) nla_data(nla); 1840 } 1841 1842 /** 1843 * nla_get_u8_default - return payload of u8 attribute or default 1844 * @nla: u8 netlink attribute, may be %NULL 1845 * @defvalue: default value to use if @nla is %NULL 1846 * 1847 * Return: the value of the attribute, or the default value if not present 1848 */ 1849 static inline u8 nla_get_u8_default(const struct nlattr *nla, u8 defvalue) 1850 { 1851 if (!nla) 1852 return defvalue; 1853 return nla_get_u8(nla); 1854 } 1855 1856 /** 1857 * nla_get_u64 - return payload of u64 attribute 1858 * @nla: u64 netlink attribute 1859 */ 1860 static inline u64 nla_get_u64(const struct nlattr *nla) 1861 { 1862 u64 tmp; 1863 1864 nla_memcpy(&tmp, nla, sizeof(tmp)); 1865 1866 return tmp; 1867 } 1868 1869 /** 1870 * nla_get_u64_default - return payload of u64 attribute or default 1871 * @nla: u64 netlink attribute, may be %NULL 1872 * @defvalue: default value to use if @nla is %NULL 1873 * 1874 * Return: the value of the attribute, or the default value if not present 1875 */ 1876 static inline u64 nla_get_u64_default(const struct nlattr *nla, u64 defvalue) 1877 { 1878 if (!nla) 1879 return defvalue; 1880 return nla_get_u64(nla); 1881 } 1882 1883 /** 1884 * nla_get_uint - return payload of uint attribute 1885 * @nla: uint netlink attribute 1886 */ 1887 static inline u64 nla_get_uint(const struct nlattr *nla) 1888 { 1889 if (nla_len(nla) == sizeof(u32)) 1890 return nla_get_u32(nla); 1891 return nla_get_u64(nla); 1892 } 1893 1894 /** 1895 * nla_get_uint_default - return payload of uint attribute or default 1896 * @nla: uint netlink attribute, may be %NULL 1897 * @defvalue: default value to use if @nla is %NULL 1898 * 1899 * Return: the value of the attribute, or the default value if not present 1900 */ 1901 static inline u64 nla_get_uint_default(const struct nlattr *nla, u64 defvalue) 1902 { 1903 if (!nla) 1904 return defvalue; 1905 return nla_get_uint(nla); 1906 } 1907 1908 /** 1909 * nla_get_be64 - return payload of __be64 attribute 1910 * @nla: __be64 netlink attribute 1911 */ 1912 static inline __be64 nla_get_be64(const struct nlattr *nla) 1913 { 1914 __be64 tmp; 1915 1916 nla_memcpy(&tmp, nla, sizeof(tmp)); 1917 1918 return tmp; 1919 } 1920 1921 /** 1922 * nla_get_be64_default - return payload of be64 attribute or default 1923 * @nla: __be64 netlink attribute, may be %NULL 1924 * @defvalue: default value to use if @nla is %NULL 1925 * 1926 * Return: the value of the attribute, or the default value if not present 1927 */ 1928 static inline __be64 nla_get_be64_default(const struct nlattr *nla, 1929 __be64 defvalue) 1930 { 1931 if (!nla) 1932 return defvalue; 1933 return nla_get_be64(nla); 1934 } 1935 1936 /** 1937 * nla_get_le64 - return payload of __le64 attribute 1938 * @nla: __le64 netlink attribute 1939 */ 1940 static inline __le64 nla_get_le64(const struct nlattr *nla) 1941 { 1942 return *(__le64 *) nla_data(nla); 1943 } 1944 1945 /** 1946 * nla_get_le64_default - return payload of le64 attribute or default 1947 * @nla: __le64 netlink attribute, may be %NULL 1948 * @defvalue: default value to use if @nla is %NULL 1949 * 1950 * Return: the value of the attribute, or the default value if not present 1951 */ 1952 static inline __le64 nla_get_le64_default(const struct nlattr *nla, 1953 __le64 defvalue) 1954 { 1955 if (!nla) 1956 return defvalue; 1957 return nla_get_le64(nla); 1958 } 1959 1960 /** 1961 * nla_get_s32 - return payload of s32 attribute 1962 * @nla: s32 netlink attribute 1963 */ 1964 static inline s32 nla_get_s32(const struct nlattr *nla) 1965 { 1966 return *(s32 *) nla_data(nla); 1967 } 1968 1969 /** 1970 * nla_get_s32_default - return payload of s32 attribute or default 1971 * @nla: s32 netlink attribute, may be %NULL 1972 * @defvalue: default value to use if @nla is %NULL 1973 * 1974 * Return: the value of the attribute, or the default value if not present 1975 */ 1976 static inline s32 nla_get_s32_default(const struct nlattr *nla, s32 defvalue) 1977 { 1978 if (!nla) 1979 return defvalue; 1980 return nla_get_s32(nla); 1981 } 1982 1983 /** 1984 * nla_get_s16 - return payload of s16 attribute 1985 * @nla: s16 netlink attribute 1986 */ 1987 static inline s16 nla_get_s16(const struct nlattr *nla) 1988 { 1989 return *(s16 *) nla_data(nla); 1990 } 1991 1992 /** 1993 * nla_get_s16_default - return payload of s16 attribute or default 1994 * @nla: s16 netlink attribute, may be %NULL 1995 * @defvalue: default value to use if @nla is %NULL 1996 * 1997 * Return: the value of the attribute, or the default value if not present 1998 */ 1999 static inline s16 nla_get_s16_default(const struct nlattr *nla, s16 defvalue) 2000 { 2001 if (!nla) 2002 return defvalue; 2003 return nla_get_s16(nla); 2004 } 2005 2006 /** 2007 * nla_get_s8 - return payload of s8 attribute 2008 * @nla: s8 netlink attribute 2009 */ 2010 static inline s8 nla_get_s8(const struct nlattr *nla) 2011 { 2012 return *(s8 *) nla_data(nla); 2013 } 2014 2015 /** 2016 * nla_get_s8_default - return payload of s8 attribute or default 2017 * @nla: s8 netlink attribute, may be %NULL 2018 * @defvalue: default value to use if @nla is %NULL 2019 * 2020 * Return: the value of the attribute, or the default value if not present 2021 */ 2022 static inline s8 nla_get_s8_default(const struct nlattr *nla, s8 defvalue) 2023 { 2024 if (!nla) 2025 return defvalue; 2026 return nla_get_s8(nla); 2027 } 2028 2029 /** 2030 * nla_get_s64 - return payload of s64 attribute 2031 * @nla: s64 netlink attribute 2032 */ 2033 static inline s64 nla_get_s64(const struct nlattr *nla) 2034 { 2035 s64 tmp; 2036 2037 nla_memcpy(&tmp, nla, sizeof(tmp)); 2038 2039 return tmp; 2040 } 2041 2042 /** 2043 * nla_get_s64_default - return payload of s64 attribute or default 2044 * @nla: s64 netlink attribute, may be %NULL 2045 * @defvalue: default value to use if @nla is %NULL 2046 * 2047 * Return: the value of the attribute, or the default value if not present 2048 */ 2049 static inline s64 nla_get_s64_default(const struct nlattr *nla, s64 defvalue) 2050 { 2051 if (!nla) 2052 return defvalue; 2053 return nla_get_s64(nla); 2054 } 2055 2056 /** 2057 * nla_get_sint - return payload of uint attribute 2058 * @nla: uint netlink attribute 2059 */ 2060 static inline s64 nla_get_sint(const struct nlattr *nla) 2061 { 2062 if (nla_len(nla) == sizeof(s32)) 2063 return nla_get_s32(nla); 2064 return nla_get_s64(nla); 2065 } 2066 2067 /** 2068 * nla_get_sint_default - return payload of sint attribute or default 2069 * @nla: sint netlink attribute, may be %NULL 2070 * @defvalue: default value to use if @nla is %NULL 2071 * 2072 * Return: the value of the attribute, or the default value if not present 2073 */ 2074 static inline s64 nla_get_sint_default(const struct nlattr *nla, s64 defvalue) 2075 { 2076 if (!nla) 2077 return defvalue; 2078 return nla_get_sint(nla); 2079 } 2080 2081 /** 2082 * nla_get_flag - return payload of flag attribute 2083 * @nla: flag netlink attribute 2084 */ 2085 static inline int nla_get_flag(const struct nlattr *nla) 2086 { 2087 return !!nla; 2088 } 2089 2090 /** 2091 * nla_get_msecs - return payload of msecs attribute 2092 * @nla: msecs netlink attribute 2093 * 2094 * Returns the number of milliseconds in jiffies. 2095 */ 2096 static inline unsigned long nla_get_msecs(const struct nlattr *nla) 2097 { 2098 u64 msecs = nla_get_u64(nla); 2099 2100 return msecs_to_jiffies((unsigned long) msecs); 2101 } 2102 2103 /** 2104 * nla_get_msecs_default - return payload of msecs attribute or default 2105 * @nla: msecs netlink attribute, may be %NULL 2106 * @defvalue: default value to use if @nla is %NULL 2107 * 2108 * Return: the value of the attribute, or the default value if not present 2109 */ 2110 static inline unsigned long nla_get_msecs_default(const struct nlattr *nla, 2111 unsigned long defvalue) 2112 { 2113 if (!nla) 2114 return defvalue; 2115 return nla_get_msecs(nla); 2116 } 2117 2118 /** 2119 * nla_get_in_addr - return payload of IPv4 address attribute 2120 * @nla: IPv4 address netlink attribute 2121 */ 2122 static inline __be32 nla_get_in_addr(const struct nlattr *nla) 2123 { 2124 return *(__be32 *) nla_data(nla); 2125 } 2126 2127 /** 2128 * nla_get_in_addr_default - return payload of be32 attribute or default 2129 * @nla: IPv4 address netlink attribute, may be %NULL 2130 * @defvalue: default value to use if @nla is %NULL 2131 * 2132 * Return: the value of the attribute, or the default value if not present 2133 */ 2134 static inline __be32 nla_get_in_addr_default(const struct nlattr *nla, 2135 __be32 defvalue) 2136 { 2137 if (!nla) 2138 return defvalue; 2139 return nla_get_in_addr(nla); 2140 } 2141 2142 /** 2143 * nla_get_in6_addr - return payload of IPv6 address attribute 2144 * @nla: IPv6 address netlink attribute 2145 */ 2146 static inline struct in6_addr nla_get_in6_addr(const struct nlattr *nla) 2147 { 2148 struct in6_addr tmp; 2149 2150 nla_memcpy(&tmp, nla, sizeof(tmp)); 2151 return tmp; 2152 } 2153 2154 /** 2155 * nla_get_bitfield32 - return payload of 32 bitfield attribute 2156 * @nla: nla_bitfield32 attribute 2157 */ 2158 static inline struct nla_bitfield32 nla_get_bitfield32(const struct nlattr *nla) 2159 { 2160 struct nla_bitfield32 tmp; 2161 2162 nla_memcpy(&tmp, nla, sizeof(tmp)); 2163 return tmp; 2164 } 2165 2166 /** 2167 * nla_memdup - duplicate attribute memory (kmemdup) 2168 * @src: netlink attribute to duplicate from 2169 * @gfp: GFP mask 2170 */ 2171 static inline void *nla_memdup_noprof(const struct nlattr *src, gfp_t gfp) 2172 { 2173 return kmemdup_noprof(nla_data(src), nla_len(src), gfp); 2174 } 2175 #define nla_memdup(...) alloc_hooks(nla_memdup_noprof(__VA_ARGS__)) 2176 2177 /** 2178 * nla_nest_start_noflag - Start a new level of nested attributes 2179 * @skb: socket buffer to add attributes to 2180 * @attrtype: attribute type of container 2181 * 2182 * This function exists for backward compatibility to use in APIs which never 2183 * marked their nest attributes with NLA_F_NESTED flag. New APIs should use 2184 * nla_nest_start() which sets the flag. 2185 * 2186 * Returns the container attribute or NULL on error 2187 */ 2188 static inline struct nlattr *nla_nest_start_noflag(struct sk_buff *skb, 2189 int attrtype) 2190 { 2191 struct nlattr *start = (struct nlattr *)skb_tail_pointer(skb); 2192 2193 if (nla_put(skb, attrtype, 0, NULL) < 0) 2194 return NULL; 2195 2196 return start; 2197 } 2198 2199 /** 2200 * nla_nest_start - Start a new level of nested attributes, with NLA_F_NESTED 2201 * @skb: socket buffer to add attributes to 2202 * @attrtype: attribute type of container 2203 * 2204 * Unlike nla_nest_start_noflag(), mark the nest attribute with NLA_F_NESTED 2205 * flag. This is the preferred function to use in new code. 2206 * 2207 * Returns the container attribute or NULL on error 2208 */ 2209 static inline struct nlattr *nla_nest_start(struct sk_buff *skb, int attrtype) 2210 { 2211 return nla_nest_start_noflag(skb, attrtype | NLA_F_NESTED); 2212 } 2213 2214 /** 2215 * nla_nest_end - Finalize nesting of attributes 2216 * @skb: socket buffer the attributes are stored in 2217 * @start: container attribute 2218 * 2219 * Corrects the container attribute header to include the all 2220 * appended attributes. 2221 * 2222 * Returns the total data length of the skb. 2223 */ 2224 static inline int nla_nest_end(struct sk_buff *skb, struct nlattr *start) 2225 { 2226 start->nla_len = skb_tail_pointer(skb) - (unsigned char *)start; 2227 return skb->len; 2228 } 2229 2230 /** 2231 * nla_nest_cancel - Cancel nesting of attributes 2232 * @skb: socket buffer the message is stored in 2233 * @start: container attribute 2234 * 2235 * Removes the container attribute and including all nested 2236 * attributes. Returns -EMSGSIZE 2237 */ 2238 static inline void nla_nest_cancel(struct sk_buff *skb, struct nlattr *start) 2239 { 2240 nlmsg_trim(skb, start); 2241 } 2242 2243 /** 2244 * __nla_validate_nested - Validate a stream of nested attributes 2245 * @start: container attribute 2246 * @maxtype: maximum attribute type to be expected 2247 * @policy: validation policy 2248 * @validate: validation strictness 2249 * @extack: extended ACK report struct 2250 * 2251 * Validates all attributes in the nested attribute stream against the 2252 * specified policy. Attributes with a type exceeding maxtype will be 2253 * ignored. See documentation of struct nla_policy for more details. 2254 * 2255 * Returns 0 on success or a negative error code. 2256 */ 2257 static inline int __nla_validate_nested(const struct nlattr *start, int maxtype, 2258 const struct nla_policy *policy, 2259 unsigned int validate, 2260 struct netlink_ext_ack *extack) 2261 { 2262 return __nla_validate(nla_data(start), nla_len(start), maxtype, policy, 2263 validate, extack); 2264 } 2265 2266 static inline int 2267 nla_validate_nested(const struct nlattr *start, int maxtype, 2268 const struct nla_policy *policy, 2269 struct netlink_ext_ack *extack) 2270 { 2271 return __nla_validate_nested(start, maxtype, policy, 2272 NL_VALIDATE_STRICT, extack); 2273 } 2274 2275 static inline int 2276 nla_validate_nested_deprecated(const struct nlattr *start, int maxtype, 2277 const struct nla_policy *policy, 2278 struct netlink_ext_ack *extack) 2279 { 2280 return __nla_validate_nested(start, maxtype, policy, 2281 NL_VALIDATE_LIBERAL, extack); 2282 } 2283 2284 /** 2285 * nla_need_padding_for_64bit - test 64-bit alignment of the next attribute 2286 * @skb: socket buffer the message is stored in 2287 * 2288 * Return true if padding is needed to align the next attribute (nla_data()) to 2289 * a 64-bit aligned area. 2290 */ 2291 static inline bool nla_need_padding_for_64bit(struct sk_buff *skb) 2292 { 2293 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS 2294 /* The nlattr header is 4 bytes in size, that's why we test 2295 * if the skb->data _is_ aligned. A NOP attribute, plus 2296 * nlattr header for next attribute, will make nla_data() 2297 * 8-byte aligned. 2298 */ 2299 if (IS_ALIGNED((unsigned long)skb_tail_pointer(skb), 8)) 2300 return true; 2301 #endif 2302 return false; 2303 } 2304 2305 /** 2306 * nla_align_64bit - 64-bit align the nla_data() of next attribute 2307 * @skb: socket buffer the message is stored in 2308 * @padattr: attribute type for the padding 2309 * 2310 * Conditionally emit a padding netlink attribute in order to make 2311 * the next attribute we emit have a 64-bit aligned nla_data() area. 2312 * This will only be done in architectures which do not have 2313 * CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS defined. 2314 * 2315 * Returns zero on success or a negative error code. 2316 */ 2317 static inline int nla_align_64bit(struct sk_buff *skb, int padattr) 2318 { 2319 if (nla_need_padding_for_64bit(skb) && 2320 !nla_reserve(skb, padattr, 0)) 2321 return -EMSGSIZE; 2322 2323 return 0; 2324 } 2325 2326 /** 2327 * nla_total_size_64bit - total length of attribute including padding 2328 * @payload: length of payload 2329 */ 2330 static inline int nla_total_size_64bit(int payload) 2331 { 2332 return NLA_ALIGN(nla_attr_size(payload)) 2333 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS 2334 + NLA_ALIGN(nla_attr_size(0)) 2335 #endif 2336 ; 2337 } 2338 2339 /** 2340 * nla_for_each_attr - iterate over a stream of attributes 2341 * @pos: loop counter, set to current attribute 2342 * @head: head of attribute stream 2343 * @len: length of attribute stream 2344 * @rem: initialized to len, holds bytes currently remaining in stream 2345 */ 2346 #define nla_for_each_attr(pos, head, len, rem) \ 2347 for (pos = head, rem = len; \ 2348 nla_ok(pos, rem); \ 2349 pos = nla_next(pos, &(rem))) 2350 2351 /** 2352 * nla_for_each_attr_type - iterate over a stream of attributes 2353 * @pos: loop counter, set to current attribute 2354 * @type: required attribute type for @pos 2355 * @head: head of attribute stream 2356 * @len: length of attribute stream 2357 * @rem: initialized to len, holds bytes currently remaining in stream 2358 */ 2359 #define nla_for_each_attr_type(pos, type, head, len, rem) \ 2360 nla_for_each_attr(pos, head, len, rem) \ 2361 if (nla_type(pos) == type) 2362 2363 /** 2364 * nla_for_each_nested - iterate over nested attributes 2365 * @pos: loop counter, set to current attribute 2366 * @nla: attribute containing the nested attributes 2367 * @rem: initialized to len, holds bytes currently remaining in stream 2368 */ 2369 #define nla_for_each_nested(pos, nla, rem) \ 2370 nla_for_each_attr(pos, nla_data(nla), nla_len(nla), rem) 2371 2372 /** 2373 * nla_for_each_nested_type - iterate over nested attributes 2374 * @pos: loop counter, set to current attribute 2375 * @type: required attribute type for @pos 2376 * @nla: attribute containing the nested attributes 2377 * @rem: initialized to len, holds bytes currently remaining in stream 2378 */ 2379 #define nla_for_each_nested_type(pos, type, nla, rem) \ 2380 nla_for_each_nested(pos, nla, rem) \ 2381 if (nla_type(pos) == type) 2382 2383 /** 2384 * nla_is_last - Test if attribute is last in stream 2385 * @nla: attribute to test 2386 * @rem: bytes remaining in stream 2387 */ 2388 static inline bool nla_is_last(const struct nlattr *nla, int rem) 2389 { 2390 return nla->nla_len == rem; 2391 } 2392 2393 void nla_get_range_unsigned(const struct nla_policy *pt, 2394 struct netlink_range_validation *range); 2395 void nla_get_range_signed(const struct nla_policy *pt, 2396 struct netlink_range_validation_signed *range); 2397 2398 struct netlink_policy_dump_state; 2399 2400 int netlink_policy_dump_add_policy(struct netlink_policy_dump_state **pstate, 2401 const struct nla_policy *policy, 2402 unsigned int maxtype); 2403 int netlink_policy_dump_get_policy_idx(struct netlink_policy_dump_state *state, 2404 const struct nla_policy *policy, 2405 unsigned int maxtype); 2406 bool netlink_policy_dump_loop(struct netlink_policy_dump_state *state); 2407 int netlink_policy_dump_write(struct sk_buff *skb, 2408 struct netlink_policy_dump_state *state); 2409 int netlink_policy_dump_attr_size_estimate(const struct nla_policy *pt); 2410 int netlink_policy_dump_write_attr(struct sk_buff *skb, 2411 const struct nla_policy *pt, 2412 int nestattr); 2413 void netlink_policy_dump_free(struct netlink_policy_dump_state *state); 2414 2415 #endif 2416