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_free()			free a netlink message
  45 *
  46 * Message Sending:
  47 *   nlmsg_multicast()			multicast message to several groups
  48 *   nlmsg_unicast()			unicast a message to a single socket
  49 *   nlmsg_notify()			send notification message
  50 *
  51 * Message Length Calculations:
  52 *   nlmsg_msg_size(payload)		length of message w/o padding
  53 *   nlmsg_total_size(payload)		length of message w/ padding
  54 *   nlmsg_padlen(payload)		length of padding at tail
  55 *
  56 * Message Payload Access:
  57 *   nlmsg_data(nlh)			head of message payload
  58 *   nlmsg_len(nlh)			length of message payload
  59 *   nlmsg_attrdata(nlh, hdrlen)	head of attributes data
  60 *   nlmsg_attrlen(nlh, hdrlen)		length of attributes data
  61 *
  62 * Message Parsing:
  63 *   nlmsg_ok(nlh, remaining)		does nlh fit into remaining bytes?
  64 *   nlmsg_next(nlh, remaining)		get next netlink message
  65 *   nlmsg_parse()			parse attributes of a message
  66 *   nlmsg_find_attr()			find an attribute in a message
  67 *   nlmsg_for_each_msg()		loop over all messages
  68 *   nlmsg_validate()			validate netlink message incl. attrs
  69 *   nlmsg_for_each_attr()		loop over all attributes
  70 *
  71 * Misc:
  72 *   nlmsg_report()			report back to application?
  73 *
  74 * ------------------------------------------------------------------------
  75 *                          Attributes Interface
  76 * ------------------------------------------------------------------------
  77 *
  78 * Attribute Format:
  79 *    <------- nla_total_size(payload) ------->
  80 *    <---- nla_attr_size(payload) ----->
  81 *   +----------+- - -+- - - - - - - - - +- - -+-------- - -
  82 *   |  Header  | Pad |     Payload      | Pad |  Header
  83 *   +----------+- - -+- - - - - - - - - +- - -+-------- - -
  84 *                     <- nla_len(nla) ->      ^
  85 *   nla_data(nla)----^                        |
  86 *   nla_next(nla)-----------------------------'
  87 *
  88 * Data Structures:
  89 *   struct nlattr			netlink attribute header
  90 *
  91 * Attribute Construction:
  92 *   nla_reserve(skb, type, len)	reserve room for an attribute
  93 *   nla_reserve_nohdr(skb, len)	reserve room for an attribute w/o hdr
  94 *   nla_put(skb, type, len, data)	add attribute to skb
  95 *   nla_put_nohdr(skb, len, data)	add attribute w/o hdr
  96 *   nla_append(skb, len, data)		append data to skb
  97 *
  98 * Attribute Construction for Basic Types:
  99 *   nla_put_u8(skb, type, value)	add u8 attribute to skb
 100 *   nla_put_u16(skb, type, value)	add u16 attribute to skb
 101 *   nla_put_u32(skb, type, value)	add u32 attribute to skb
 102 *   nla_put_u64_64bit(skb, type,
 103 *                     value, padattr)	add u64 attribute to skb
 104 *   nla_put_s8(skb, type, value)	add s8 attribute to skb
 105 *   nla_put_s16(skb, type, value)	add s16 attribute to skb
 106 *   nla_put_s32(skb, type, value)	add s32 attribute to skb
 107 *   nla_put_s64(skb, type, value,
 108 *               padattr)		add s64 attribute to skb
 109 *   nla_put_string(skb, type, str)	add string attribute to skb
 110 *   nla_put_flag(skb, type)		add flag attribute to skb
 111 *   nla_put_msecs(skb, type, jiffies,
 112 *                 padattr)		add msecs attribute to skb
 113 *   nla_put_in_addr(skb, type, addr)	add IPv4 address attribute to skb
 114 *   nla_put_in6_addr(skb, type, addr)	add IPv6 address attribute to skb
 115 *
 116 * Nested Attributes Construction:
 117 *   nla_nest_start(skb, type)		start a nested attribute
 118 *   nla_nest_end(skb, nla)		finalize a nested attribute
 119 *   nla_nest_cancel(skb, nla)		cancel nested attribute construction
 120 *
 121 * Attribute Length Calculations:
 122 *   nla_attr_size(payload)		length of attribute w/o padding
 123 *   nla_total_size(payload)		length of attribute w/ padding
 124 *   nla_padlen(payload)		length of padding
 125 *
 126 * Attribute Payload Access:
 127 *   nla_data(nla)			head of attribute payload
 128 *   nla_len(nla)			length of attribute payload
 129 *
 130 * Attribute Payload Access for Basic Types:
 131 *   nla_get_u8(nla)			get payload for a u8 attribute
 132 *   nla_get_u16(nla)			get payload for a u16 attribute
 133 *   nla_get_u32(nla)			get payload for a u32 attribute
 134 *   nla_get_u64(nla)			get payload for a u64 attribute
 135 *   nla_get_s8(nla)			get payload for a s8 attribute
 136 *   nla_get_s16(nla)			get payload for a s16 attribute
 137 *   nla_get_s32(nla)			get payload for a s32 attribute
 138 *   nla_get_s64(nla)			get payload for a s64 attribute
 139 *   nla_get_flag(nla)			return 1 if flag is true
 140 *   nla_get_msecs(nla)			get payload for a msecs attribute
 141 *
 142 * Attribute Misc:
 143 *   nla_memcpy(dest, nla, count)	copy attribute into memory
 144 *   nla_memcmp(nla, data, size)	compare attribute with memory area
 145 *   nla_strlcpy(dst, nla, size)	copy attribute to a sized string
 146 *   nla_strcmp(nla, str)		compare attribute with string
 147 *
 148 * Attribute Parsing:
 149 *   nla_ok(nla, remaining)		does nla fit into remaining bytes?
 150 *   nla_next(nla, remaining)		get next netlink attribute
 151 *   nla_validate()			validate a stream of attributes
 152 *   nla_validate_nested()		validate a stream of nested attributes
 153 *   nla_find()				find attribute in stream of attributes
 154 *   nla_find_nested()			find attribute in nested attributes
 155 *   nla_parse()			parse and validate stream of attrs
 156 *   nla_parse_nested()			parse nested attributes
 157 *   nla_for_each_attr()		loop over all attributes
 158 *   nla_for_each_nested()		loop over the nested attributes
 159 *=========================================================================
 160 */
 161
 162 /**
 163  * Standard attribute types to specify validation policy
 164  */
 165enum {
 166	NLA_UNSPEC,
 167	NLA_U8,
 168	NLA_U16,
 169	NLA_U32,
 170	NLA_U64,
 171	NLA_STRING,
 172	NLA_FLAG,
 173	NLA_MSECS,
 174	NLA_NESTED,
 175	NLA_NESTED_ARRAY,
 176	NLA_NUL_STRING,
 177	NLA_BINARY,
 178	NLA_S8,
 179	NLA_S16,
 180	NLA_S32,
 181	NLA_S64,
 182	NLA_BITFIELD32,
 183	NLA_REJECT,
 184	NLA_EXACT_LEN,
 185	NLA_EXACT_LEN_WARN,
 186	NLA_MIN_LEN,
 187	__NLA_TYPE_MAX,
 188};
 189
 190#define NLA_TYPE_MAX (__NLA_TYPE_MAX - 1)
 191
 192enum nla_policy_validation {
 193	NLA_VALIDATE_NONE,
 194	NLA_VALIDATE_RANGE,
 195	NLA_VALIDATE_MIN,
 196	NLA_VALIDATE_MAX,
 197	NLA_VALIDATE_FUNCTION,
 198};
 199
 200/**
 201 * struct nla_policy - attribute validation policy
 202 * @type: Type of attribute or NLA_UNSPEC
 203 * @validation_type: type of attribute validation done in addition to
 204 *	type-specific validation (e.g. range, function call), see
 205 *	&enum nla_policy_validation
 206 * @len: Type specific length of payload
 207 *
 208 * Policies are defined as arrays of this struct, the array must be
 209 * accessible by attribute type up to the highest identifier to be expected.
 210 *
 211 * Meaning of `len' field:
 212 *    NLA_STRING           Maximum length of string
 213 *    NLA_NUL_STRING       Maximum length of string (excluding NUL)
 214 *    NLA_FLAG             Unused
 215 *    NLA_BINARY           Maximum length of attribute payload
 216 *    NLA_MIN_LEN          Minimum length of attribute payload
 217 *    NLA_NESTED,
 218 *    NLA_NESTED_ARRAY     Length verification is done by checking len of
 219 *                         nested header (or empty); len field is used if
 220 *                         validation_data is also used, for the max attr
 221 *                         number in the nested policy.
 222 *    NLA_U8, NLA_U16,
 223 *    NLA_U32, NLA_U64,
 224 *    NLA_S8, NLA_S16,
 225 *    NLA_S32, NLA_S64,
 226 *    NLA_MSECS            Leaving the length field zero will verify the
 227 *                         given type fits, using it verifies minimum length
 228 *                         just like "All other"
 229 *    NLA_BITFIELD32       Unused
 230 *    NLA_REJECT           Unused
 231 *    NLA_EXACT_LEN        Attribute must have exactly this length, otherwise
 232 *                         it is rejected.
 233 *    NLA_EXACT_LEN_WARN   Attribute should have exactly this length, a warning
 234 *                         is logged if it is longer, shorter is rejected.
 235 *    NLA_MIN_LEN          Minimum length of attribute payload
 236 *    All other            Minimum length of attribute payload
 237 *
 238 * Meaning of `validation_data' field:
 239 *    NLA_BITFIELD32       This is a 32-bit bitmap/bitselector attribute and
 240 *                         validation data must point to a u32 value of valid
 241 *                         flags
 242 *    NLA_REJECT           This attribute is always rejected and validation data
 243 *                         may point to a string to report as the error instead
 244 *                         of the generic one in extended ACK.
 245 *    NLA_NESTED           Points to a nested policy to validate, must also set
 246 *                         `len' to the max attribute number.
 247 *                         Note that nla_parse() will validate, but of course not
 248 *                         parse, the nested sub-policies.
 249 *    NLA_NESTED_ARRAY     Points to a nested policy to validate, must also set
 250 *                         `len' to the max attribute number. The difference to
 251 *                         NLA_NESTED is the structure - NLA_NESTED has the
 252 *                         nested attributes directly inside, while an array has
 253 *                         the nested attributes at another level down and the
 254 *                         attributes directly in the nesting don't matter.
 255 *    All other            Unused - but note that it's a union
 256 *
 257 * Meaning of `min' and `max' fields, use via NLA_POLICY_MIN, NLA_POLICY_MAX
 258 * and NLA_POLICY_RANGE:
 259 *    NLA_U8,
 260 *    NLA_U16,
 261 *    NLA_U32,
 262 *    NLA_U64,
 263 *    NLA_S8,
 264 *    NLA_S16,
 265 *    NLA_S32,
 266 *    NLA_S64              These are used depending on the validation_type
 267 *                         field, if that is min/max/range then the minimum,
 268 *                         maximum and both are used (respectively) to check
 269 *                         the value of the integer attribute.
 270 *                         Note that in the interest of code simplicity and
 271 *                         struct size both limits are s16, so you cannot
 272 *                         enforce a range that doesn't fall within the range
 273 *                         of s16 - do that as usual in the code instead.
 274 *    All other            Unused - but note that it's a union
 275 *
 276 * Meaning of `validate' field, use via NLA_POLICY_VALIDATE_FN:
 277 *    NLA_BINARY           Validation function called for the attribute,
 278 *                         not compatible with use of the validation_data
 279 *                         as in NLA_BITFIELD32, NLA_REJECT, NLA_NESTED and
 280 *                         NLA_NESTED_ARRAY.
 281 *    All other            Unused - but note that it's a union
 282 *
 283 * Example:
 284 * static const struct nla_policy my_policy[ATTR_MAX+1] = {
 285 * 	[ATTR_FOO] = { .type = NLA_U16 },
 286 *	[ATTR_BAR] = { .type = NLA_STRING, .len = BARSIZ },
 287 *	[ATTR_BAZ] = { .type = NLA_EXACT_LEN, .len = sizeof(struct mystruct) },
 288 *	[ATTR_GOO] = { .type = NLA_BITFIELD32, .validation_data = &myvalidflags },
 289 * };
 290 */
 291struct nla_policy {
 292	u8		type;
 293	u8		validation_type;
 294	u16		len;
 295	union {
 296		const void *validation_data;
 297		struct {
 298			s16 min, max;
 299		};
 300		int (*validate)(const struct nlattr *attr,
 301				struct netlink_ext_ack *extack);
 302		/* This entry is special, and used for the attribute at index 0
 303		 * only, and specifies special data about the policy, namely it
 304		 * specifies the "boundary type" where strict length validation
 305		 * starts for any attribute types >= this value, also, strict
 306		 * nesting validation starts here.
 307		 *
 308		 * Additionally, it means that NLA_UNSPEC is actually NLA_REJECT
 309		 * for any types >= this, so need to use NLA_MIN_LEN to get the
 310		 * previous pure { .len = xyz } behaviour. The advantage of this
 311		 * is that types not specified in the policy will be rejected.
 312		 *
 313		 * For completely new families it should be set to 1 so that the
 314		 * validation is enforced for all attributes. For existing ones
 315		 * it should be set at least when new attributes are added to
 316		 * the enum used by the policy, and be set to the new value that
 317		 * was added to enforce strict validation from thereon.
 318		 */
 319		u16 strict_start_type;
 320	};
 321};
 322
 323#define NLA_POLICY_EXACT_LEN(_len)	{ .type = NLA_EXACT_LEN, .len = _len }
 324#define NLA_POLICY_EXACT_LEN_WARN(_len)	{ .type = NLA_EXACT_LEN_WARN, \
 325					  .len = _len }
 326#define NLA_POLICY_MIN_LEN(_len)	{ .type = NLA_MIN_LEN, .len = _len }
 327
 328#define NLA_POLICY_ETH_ADDR		NLA_POLICY_EXACT_LEN(ETH_ALEN)
 329#define NLA_POLICY_ETH_ADDR_COMPAT	NLA_POLICY_EXACT_LEN_WARN(ETH_ALEN)
 330
 331#define _NLA_POLICY_NESTED(maxattr, policy) \
 332	{ .type = NLA_NESTED, .validation_data = policy, .len = maxattr }
 333#define _NLA_POLICY_NESTED_ARRAY(maxattr, policy) \
 334	{ .type = NLA_NESTED_ARRAY, .validation_data = policy, .len = maxattr }
 335#define NLA_POLICY_NESTED(policy) \
 336	_NLA_POLICY_NESTED(ARRAY_SIZE(policy) - 1, policy)
 337#define NLA_POLICY_NESTED_ARRAY(policy) \
 338	_NLA_POLICY_NESTED_ARRAY(ARRAY_SIZE(policy) - 1, policy)
 339
 340#define __NLA_ENSURE(condition) BUILD_BUG_ON_ZERO(!(condition))
 341#define NLA_ENSURE_INT_TYPE(tp)				\
 342	(__NLA_ENSURE(tp == NLA_S8 || tp == NLA_U8 ||	\
 343		      tp == NLA_S16 || tp == NLA_U16 ||	\
 344		      tp == NLA_S32 || tp == NLA_U32 ||	\
 345		      tp == NLA_S64 || tp == NLA_U64) + tp)
 346#define NLA_ENSURE_NO_VALIDATION_PTR(tp)		\
 347	(__NLA_ENSURE(tp != NLA_BITFIELD32 &&		\
 348		      tp != NLA_REJECT &&		\
 349		      tp != NLA_NESTED &&		\
 350		      tp != NLA_NESTED_ARRAY) + tp)
 351
 352#define NLA_POLICY_RANGE(tp, _min, _max) {		\
 353	.type = NLA_ENSURE_INT_TYPE(tp),		\
 354	.validation_type = NLA_VALIDATE_RANGE,		\
 355	.min = _min,					\
 356	.max = _max					\
 357}
 358
 359#define NLA_POLICY_MIN(tp, _min) {			\
 360	.type = NLA_ENSURE_INT_TYPE(tp),		\
 361	.validation_type = NLA_VALIDATE_MIN,		\
 362	.min = _min,					\
 363}
 364
 365#define NLA_POLICY_MAX(tp, _max) {			\
 366	.type = NLA_ENSURE_INT_TYPE(tp),		\
 367	.validation_type = NLA_VALIDATE_MAX,		\
 368	.max = _max,					\
 369}
 370
 371#define NLA_POLICY_VALIDATE_FN(tp, fn, ...) {		\
 372	.type = NLA_ENSURE_NO_VALIDATION_PTR(tp),	\
 373	.validation_type = NLA_VALIDATE_FUNCTION,	\
 374	.validate = fn,					\
 375	.len = __VA_ARGS__ + 0,				\
 376}
 377
 378/**
 379 * struct nl_info - netlink source information
 380 * @nlh: Netlink message header of original request
 381 * @nl_net: Network namespace
 382 * @portid: Netlink PORTID of requesting application
 383 * @skip_notify: Skip netlink notifications to user space
 384 * @skip_notify_kernel: Skip selected in-kernel notifications
 385 */
 386struct nl_info {
 387	struct nlmsghdr		*nlh;
 388	struct net		*nl_net;
 389	u32			portid;
 390	u8			skip_notify:1,
 391				skip_notify_kernel:1;
 392};
 393
 394/**
 395 * enum netlink_validation - netlink message/attribute validation levels
 396 * @NL_VALIDATE_LIBERAL: Old-style "be liberal" validation, not caring about
 397 *	extra data at the end of the message, attributes being longer than
 398 *	they should be, or unknown attributes being present.
 399 * @NL_VALIDATE_TRAILING: Reject junk data encountered after attribute parsing.
 400 * @NL_VALIDATE_MAXTYPE: Reject attributes > max type; Together with _TRAILING
 401 *	this is equivalent to the old nla_parse_strict()/nlmsg_parse_strict().
 402 * @NL_VALIDATE_UNSPEC: Reject attributes with NLA_UNSPEC in the policy.
 403 *	This can safely be set by the kernel when the given policy has no
 404 *	NLA_UNSPEC anymore, and can thus be used to ensure policy entries
 405 *	are enforced going forward.
 406 * @NL_VALIDATE_STRICT_ATTRS: strict attribute policy parsing (e.g.
 407 *	U8, U16, U32 must have exact size, etc.)
 408 * @NL_VALIDATE_NESTED: Check that NLA_F_NESTED is set for NLA_NESTED(_ARRAY)
 409 *	and unset for other policies.
 410 */
 411enum netlink_validation {
 412	NL_VALIDATE_LIBERAL = 0,
 413	NL_VALIDATE_TRAILING = BIT(0),
 414	NL_VALIDATE_MAXTYPE = BIT(1),
 415	NL_VALIDATE_UNSPEC = BIT(2),
 416	NL_VALIDATE_STRICT_ATTRS = BIT(3),
 417	NL_VALIDATE_NESTED = BIT(4),
 418};
 419
 420#define NL_VALIDATE_DEPRECATED_STRICT (NL_VALIDATE_TRAILING |\
 421				       NL_VALIDATE_MAXTYPE)
 422#define NL_VALIDATE_STRICT (NL_VALIDATE_TRAILING |\
 423			    NL_VALIDATE_MAXTYPE |\
 424			    NL_VALIDATE_UNSPEC |\
 425			    NL_VALIDATE_STRICT_ATTRS |\
 426			    NL_VALIDATE_NESTED)
 427
 428int netlink_rcv_skb(struct sk_buff *skb,
 429		    int (*cb)(struct sk_buff *, struct nlmsghdr *,
 430			      struct netlink_ext_ack *));
 431int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 portid,
 432		 unsigned int group, int report, gfp_t flags);
 433
 434int __nla_validate(const struct nlattr *head, int len, int maxtype,
 435		   const struct nla_policy *policy, unsigned int validate,
 436		   struct netlink_ext_ack *extack);
 437int __nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head,
 438		int len, const struct nla_policy *policy, unsigned int validate,
 439		struct netlink_ext_ack *extack);
 440int nla_policy_len(const struct nla_policy *, int);
 441struct nlattr *nla_find(const struct nlattr *head, int len, int attrtype);
 442size_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize);
 443char *nla_strdup(const struct nlattr *nla, gfp_t flags);
 444int nla_memcpy(void *dest, const struct nlattr *src, int count);
 445int nla_memcmp(const struct nlattr *nla, const void *data, size_t size);
 446int nla_strcmp(const struct nlattr *nla, const char *str);
 447struct nlattr *__nla_reserve(struct sk_buff *skb, int attrtype, int attrlen);
 448struct nlattr *__nla_reserve_64bit(struct sk_buff *skb, int attrtype,
 449				   int attrlen, int padattr);
 450void *__nla_reserve_nohdr(struct sk_buff *skb, int attrlen);
 451struct nlattr *nla_reserve(struct sk_buff *skb, int attrtype, int attrlen);
 452struct nlattr *nla_reserve_64bit(struct sk_buff *skb, int attrtype,
 453				 int attrlen, int padattr);
 454void *nla_reserve_nohdr(struct sk_buff *skb, int attrlen);
 455void __nla_put(struct sk_buff *skb, int attrtype, int attrlen,
 456	       const void *data);
 457void __nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen,
 458		     const void *data, int padattr);
 459void __nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data);
 460int nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data);
 461int nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen,
 462		  const void *data, int padattr);
 463int nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data);
 464int nla_append(struct sk_buff *skb, int attrlen, const void *data);
 465
 466/**************************************************************************
 467 * Netlink Messages
 468 **************************************************************************/
 469
 470/**
 471 * nlmsg_msg_size - length of netlink message not including padding
 472 * @payload: length of message payload
 473 */
 474static inline int nlmsg_msg_size(int payload)
 475{
 476	return NLMSG_HDRLEN + payload;
 477}
 478
 479/**
 480 * nlmsg_total_size - length of netlink message including padding
 481 * @payload: length of message payload
 482 */
 483static inline int nlmsg_total_size(int payload)
 484{
 485	return NLMSG_ALIGN(nlmsg_msg_size(payload));
 486}
 487
 488/**
 489 * nlmsg_padlen - length of padding at the message's tail
 490 * @payload: length of message payload
 491 */
 492static inline int nlmsg_padlen(int payload)
 493{
 494	return nlmsg_total_size(payload) - nlmsg_msg_size(payload);
 495}
 496
 497/**
 498 * nlmsg_data - head of message payload
 499 * @nlh: netlink message header
 500 */
 501static inline void *nlmsg_data(const struct nlmsghdr *nlh)
 502{
 503	return (unsigned char *) nlh + NLMSG_HDRLEN;
 504}
 505
 506/**
 507 * nlmsg_len - length of message payload
 508 * @nlh: netlink message header
 509 */
 510static inline int nlmsg_len(const struct nlmsghdr *nlh)
 511{
 512	return nlh->nlmsg_len - NLMSG_HDRLEN;
 513}
 514
 515/**
 516 * nlmsg_attrdata - head of attributes data
 517 * @nlh: netlink message header
 518 * @hdrlen: length of family specific header
 519 */
 520static inline struct nlattr *nlmsg_attrdata(const struct nlmsghdr *nlh,
 521					    int hdrlen)
 522{
 523	unsigned char *data = nlmsg_data(nlh);
 524	return (struct nlattr *) (data + NLMSG_ALIGN(hdrlen));
 525}
 526
 527/**
 528 * nlmsg_attrlen - length of attributes data
 529 * @nlh: netlink message header
 530 * @hdrlen: length of family specific header
 531 */
 532static inline int nlmsg_attrlen(const struct nlmsghdr *nlh, int hdrlen)
 533{
 534	return nlmsg_len(nlh) - NLMSG_ALIGN(hdrlen);
 535}
 536
 537/**
 538 * nlmsg_ok - check if the netlink message fits into the remaining bytes
 539 * @nlh: netlink message header
 540 * @remaining: number of bytes remaining in message stream
 541 */
 542static inline int nlmsg_ok(const struct nlmsghdr *nlh, int remaining)
 543{
 544	return (remaining >= (int) sizeof(struct nlmsghdr) &&
 545		nlh->nlmsg_len >= sizeof(struct nlmsghdr) &&
 546		nlh->nlmsg_len <= remaining);
 547}
 548
 549/**
 550 * nlmsg_next - next netlink message in message stream
 551 * @nlh: netlink message header
 552 * @remaining: number of bytes remaining in message stream
 553 *
 554 * Returns the next netlink message in the message stream and
 555 * decrements remaining by the size of the current message.
 556 */
 557static inline struct nlmsghdr *
 558nlmsg_next(const struct nlmsghdr *nlh, int *remaining)
 559{
 560	int totlen = NLMSG_ALIGN(nlh->nlmsg_len);
 561
 562	*remaining -= totlen;
 563
 564	return (struct nlmsghdr *) ((unsigned char *) nlh + totlen);
 565}
 566
 567/**
 568 * nla_parse - Parse a stream of attributes into a tb buffer
 569 * @tb: destination array with maxtype+1 elements
 570 * @maxtype: maximum attribute type to be expected
 571 * @head: head of attribute stream
 572 * @len: length of attribute stream
 573 * @policy: validation policy
 574 * @extack: extended ACK pointer
 575 *
 576 * Parses a stream of attributes and stores a pointer to each attribute in
 577 * the tb array accessible via the attribute type. Attributes with a type
 578 * exceeding maxtype will be rejected, policy must be specified, attributes
 579 * will be validated in the strictest way possible.
 580 *
 581 * Returns 0 on success or a negative error code.
 582 */
 583static inline int nla_parse(struct nlattr **tb, int maxtype,
 584			    const struct nlattr *head, int len,
 585			    const struct nla_policy *policy,
 586			    struct netlink_ext_ack *extack)
 587{
 588	return __nla_parse(tb, maxtype, head, len, policy,
 589			   NL_VALIDATE_STRICT, extack);
 590}
 591
 592/**
 593 * nla_parse_deprecated - Parse a stream of attributes into a tb buffer
 594 * @tb: destination array with maxtype+1 elements
 595 * @maxtype: maximum attribute type to be expected
 596 * @head: head of attribute stream
 597 * @len: length of attribute stream
 598 * @policy: validation policy
 599 * @extack: extended ACK pointer
 600 *
 601 * Parses a stream of attributes and stores a pointer to each attribute in
 602 * the tb array accessible via the attribute type. Attributes with a type
 603 * exceeding maxtype will be ignored and attributes from the policy are not
 604 * always strictly validated (only for new attributes).
 605 *
 606 * Returns 0 on success or a negative error code.
 607 */
 608static inline int nla_parse_deprecated(struct nlattr **tb, int maxtype,
 609				       const struct nlattr *head, int len,
 610				       const struct nla_policy *policy,
 611				       struct netlink_ext_ack *extack)
 612{
 613	return __nla_parse(tb, maxtype, head, len, policy,
 614			   NL_VALIDATE_LIBERAL, extack);
 615}
 616
 617/**
 618 * nla_parse_deprecated_strict - Parse a stream of attributes into a tb buffer
 619 * @tb: destination array with maxtype+1 elements
 620 * @maxtype: maximum attribute type to be expected
 621 * @head: head of attribute stream
 622 * @len: length of attribute stream
 623 * @policy: validation policy
 624 * @extack: extended ACK pointer
 625 *
 626 * Parses a stream of attributes and stores a pointer to each attribute in
 627 * the tb array accessible via the attribute type. Attributes with a type
 628 * exceeding maxtype will be rejected as well as trailing data, but the
 629 * policy is not completely strictly validated (only for new attributes).
 630 *
 631 * Returns 0 on success or a negative error code.
 632 */
 633static inline int nla_parse_deprecated_strict(struct nlattr **tb, int maxtype,
 634					      const struct nlattr *head,
 635					      int len,
 636					      const struct nla_policy *policy,
 637					      struct netlink_ext_ack *extack)
 638{
 639	return __nla_parse(tb, maxtype, head, len, policy,
 640			   NL_VALIDATE_DEPRECATED_STRICT, extack);
 641}
 642
 643/**
 644 * __nlmsg_parse - parse attributes of a netlink message
 645 * @nlh: netlink message header
 646 * @hdrlen: length of family specific header
 647 * @tb: destination array with maxtype+1 elements
 648 * @maxtype: maximum attribute type to be expected
 649 * @policy: validation policy
 650 * @validate: validation strictness
 651 * @extack: extended ACK report struct
 652 *
 653 * See nla_parse()
 654 */
 655static inline int __nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen,
 656				struct nlattr *tb[], int maxtype,
 657				const struct nla_policy *policy,
 658				unsigned int validate,
 659				struct netlink_ext_ack *extack)
 660{
 661	if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) {
 662		NL_SET_ERR_MSG(extack, "Invalid header length");
 663		return -EINVAL;
 664	}
 665
 666	return __nla_parse(tb, maxtype, nlmsg_attrdata(nlh, hdrlen),
 667			   nlmsg_attrlen(nlh, hdrlen), policy, validate,
 668			   extack);
 669}
 670
 671/**
 672 * nlmsg_parse - parse attributes of a netlink message
 673 * @nlh: netlink message header
 674 * @hdrlen: length of family specific header
 675 * @tb: destination array with maxtype+1 elements
 676 * @maxtype: maximum attribute type to be expected
 677 * @validate: validation strictness
 678 * @extack: extended ACK report struct
 679 *
 680 * See nla_parse()
 681 */
 682static inline int nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen,
 683			      struct nlattr *tb[], int maxtype,
 684			      const struct nla_policy *policy,
 685			      struct netlink_ext_ack *extack)
 686{
 687	return __nlmsg_parse(nlh, hdrlen, tb, maxtype, policy,
 688			     NL_VALIDATE_STRICT, extack);
 689}
 690
 691/**
 692 * nlmsg_parse_deprecated - parse attributes of a netlink message
 693 * @nlh: netlink message header
 694 * @hdrlen: length of family specific header
 695 * @tb: destination array with maxtype+1 elements
 696 * @maxtype: maximum attribute type to be expected
 697 * @extack: extended ACK report struct
 698 *
 699 * See nla_parse_deprecated()
 700 */
 701static inline int nlmsg_parse_deprecated(const struct nlmsghdr *nlh, int hdrlen,
 702					 struct nlattr *tb[], int maxtype,
 703					 const struct nla_policy *policy,
 704					 struct netlink_ext_ack *extack)
 705{
 706	return __nlmsg_parse(nlh, hdrlen, tb, maxtype, policy,
 707			     NL_VALIDATE_LIBERAL, extack);
 708}
 709
 710/**
 711 * nlmsg_parse_deprecated_strict - parse attributes of a netlink message
 712 * @nlh: netlink message header
 713 * @hdrlen: length of family specific header
 714 * @tb: destination array with maxtype+1 elements
 715 * @maxtype: maximum attribute type to be expected
 716 * @extack: extended ACK report struct
 717 *
 718 * See nla_parse_deprecated_strict()
 719 */
 720static inline int
 721nlmsg_parse_deprecated_strict(const struct nlmsghdr *nlh, int hdrlen,
 722			      struct nlattr *tb[], int maxtype,
 723			      const struct nla_policy *policy,
 724			      struct netlink_ext_ack *extack)
 725{
 726	return __nlmsg_parse(nlh, hdrlen, tb, maxtype, policy,
 727			     NL_VALIDATE_DEPRECATED_STRICT, extack);
 728}
 729
 730/**
 731 * nlmsg_find_attr - find a specific attribute in a netlink message
 732 * @nlh: netlink message header
 733 * @hdrlen: length of familiy specific header
 734 * @attrtype: type of attribute to look for
 735 *
 736 * Returns the first attribute which matches the specified type.
 737 */
 738static inline struct nlattr *nlmsg_find_attr(const struct nlmsghdr *nlh,
 739					     int hdrlen, int attrtype)
 740{
 741	return nla_find(nlmsg_attrdata(nlh, hdrlen),
 742			nlmsg_attrlen(nlh, hdrlen), attrtype);
 743}
 744
 745/**
 746 * nla_validate_deprecated - Validate a stream of attributes
 747 * @head: head of attribute stream
 748 * @len: length of attribute stream
 749 * @maxtype: maximum attribute type to be expected
 750 * @policy: validation policy
 751 * @validate: validation strictness
 752 * @extack: extended ACK report struct
 753 *
 754 * Validates all attributes in the specified attribute stream against the
 755 * specified policy. Validation is done in liberal mode.
 756 * See documenation of struct nla_policy for more details.
 757 *
 758 * Returns 0 on success or a negative error code.
 759 */
 760static inline int nla_validate_deprecated(const struct nlattr *head, int len,
 761					  int maxtype,
 762					  const struct nla_policy *policy,
 763					  struct netlink_ext_ack *extack)
 764{
 765	return __nla_validate(head, len, maxtype, policy, NL_VALIDATE_LIBERAL,
 766			      extack);
 767}
 768
 769/**
 770 * nla_validate - Validate a stream of attributes
 771 * @head: head of attribute stream
 772 * @len: length of attribute stream
 773 * @maxtype: maximum attribute type to be expected
 774 * @policy: validation policy
 775 * @validate: validation strictness
 776 * @extack: extended ACK report struct
 777 *
 778 * Validates all attributes in the specified attribute stream against the
 779 * specified policy. Validation is done in strict mode.
 780 * See documenation of struct nla_policy for more details.
 781 *
 782 * Returns 0 on success or a negative error code.
 783 */
 784static inline int nla_validate(const struct nlattr *head, int len, int maxtype,
 785			       const struct nla_policy *policy,
 786			       struct netlink_ext_ack *extack)
 787{
 788	return __nla_validate(head, len, maxtype, policy, NL_VALIDATE_STRICT,
 789			      extack);
 790}
 791
 792/**
 793 * nlmsg_validate_deprecated - validate a netlink message including attributes
 794 * @nlh: netlinket message header
 795 * @hdrlen: length of familiy specific header
 796 * @maxtype: maximum attribute type to be expected
 797 * @policy: validation policy
 798 * @extack: extended ACK report struct
 799 */
 800static inline int nlmsg_validate_deprecated(const struct nlmsghdr *nlh,
 801					    int hdrlen, int maxtype,
 802					    const struct nla_policy *policy,
 803					    struct netlink_ext_ack *extack)
 804{
 805	if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
 806		return -EINVAL;
 807
 808	return __nla_validate(nlmsg_attrdata(nlh, hdrlen),
 809			      nlmsg_attrlen(nlh, hdrlen), maxtype,
 810			      policy, NL_VALIDATE_LIBERAL, extack);
 811}
 812
 813
 814
 815/**
 816 * nlmsg_report - need to report back to application?
 817 * @nlh: netlink message header
 818 *
 819 * Returns 1 if a report back to the application is requested.
 820 */
 821static inline int nlmsg_report(const struct nlmsghdr *nlh)
 822{
 823	return !!(nlh->nlmsg_flags & NLM_F_ECHO);
 824}
 825
 826/**
 827 * nlmsg_for_each_attr - iterate over a stream of attributes
 828 * @pos: loop counter, set to current attribute
 829 * @nlh: netlink message header
 830 * @hdrlen: length of familiy specific header
 831 * @rem: initialized to len, holds bytes currently remaining in stream
 832 */
 833#define nlmsg_for_each_attr(pos, nlh, hdrlen, rem) \
 834	nla_for_each_attr(pos, nlmsg_attrdata(nlh, hdrlen), \
 835			  nlmsg_attrlen(nlh, hdrlen), rem)
 836
 837/**
 838 * nlmsg_put - Add a new netlink message to an skb
 839 * @skb: socket buffer to store message in
 840 * @portid: netlink PORTID of requesting application
 841 * @seq: sequence number of message
 842 * @type: message type
 843 * @payload: length of message payload
 844 * @flags: message flags
 845 *
 846 * Returns NULL if the tailroom of the skb is insufficient to store
 847 * the message header and payload.
 848 */
 849static inline struct nlmsghdr *nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq,
 850					 int type, int payload, int flags)
 851{
 852	if (unlikely(skb_tailroom(skb) < nlmsg_total_size(payload)))
 853		return NULL;
 854
 855	return __nlmsg_put(skb, portid, seq, type, payload, flags);
 856}
 857
 858/**
 859 * nlmsg_put_answer - Add a new callback based netlink message to an skb
 860 * @skb: socket buffer to store message in
 861 * @cb: netlink callback
 862 * @type: message type
 863 * @payload: length of message payload
 864 * @flags: message flags
 865 *
 866 * Returns NULL if the tailroom of the skb is insufficient to store
 867 * the message header and payload.
 868 */
 869static inline struct nlmsghdr *nlmsg_put_answer(struct sk_buff *skb,
 870						struct netlink_callback *cb,
 871						int type, int payload,
 872						int flags)
 873{
 874	return nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 875			 type, payload, flags);
 876}
 877
 878/**
 879 * nlmsg_new - Allocate a new netlink message
 880 * @payload: size of the message payload
 881 * @flags: the type of memory to allocate.
 882 *
 883 * Use NLMSG_DEFAULT_SIZE if the size of the payload isn't known
 884 * and a good default is needed.
 885 */
 886static inline struct sk_buff *nlmsg_new(size_t payload, gfp_t flags)
 887{
 888	return alloc_skb(nlmsg_total_size(payload), flags);
 889}
 890
 891/**
 892 * nlmsg_end - Finalize a netlink message
 893 * @skb: socket buffer the message is stored in
 894 * @nlh: netlink message header
 895 *
 896 * Corrects the netlink message header to include the appeneded
 897 * attributes. Only necessary if attributes have been added to
 898 * the message.
 899 */
 900static inline void nlmsg_end(struct sk_buff *skb, struct nlmsghdr *nlh)
 901{
 902	nlh->nlmsg_len = skb_tail_pointer(skb) - (unsigned char *)nlh;
 903}
 904
 905/**
 906 * nlmsg_get_pos - return current position in netlink message
 907 * @skb: socket buffer the message is stored in
 908 *
 909 * Returns a pointer to the current tail of the message.
 910 */
 911static inline void *nlmsg_get_pos(struct sk_buff *skb)
 912{
 913	return skb_tail_pointer(skb);
 914}
 915
 916/**
 917 * nlmsg_trim - Trim message to a mark
 918 * @skb: socket buffer the message is stored in
 919 * @mark: mark to trim to
 920 *
 921 * Trims the message to the provided mark.
 922 */
 923static inline void nlmsg_trim(struct sk_buff *skb, const void *mark)
 924{
 925	if (mark) {
 926		WARN_ON((unsigned char *) mark < skb->data);
 927		skb_trim(skb, (unsigned char *) mark - skb->data);
 928	}
 929}
 930
 931/**
 932 * nlmsg_cancel - Cancel construction of a netlink message
 933 * @skb: socket buffer the message is stored in
 934 * @nlh: netlink message header
 935 *
 936 * Removes the complete netlink message including all
 937 * attributes from the socket buffer again.
 938 */
 939static inline void nlmsg_cancel(struct sk_buff *skb, struct nlmsghdr *nlh)
 940{
 941	nlmsg_trim(skb, nlh);
 942}
 943
 944/**
 945 * nlmsg_free - free a netlink message
 946 * @skb: socket buffer of netlink message
 947 */
 948static inline void nlmsg_free(struct sk_buff *skb)
 949{
 950	kfree_skb(skb);
 951}
 952
 953/**
 954 * nlmsg_multicast - multicast a netlink message
 955 * @sk: netlink socket to spread messages to
 956 * @skb: netlink message as socket buffer
 957 * @portid: own netlink portid to avoid sending to yourself
 958 * @group: multicast group id
 959 * @flags: allocation flags
 960 */
 961static inline int nlmsg_multicast(struct sock *sk, struct sk_buff *skb,
 962				  u32 portid, unsigned int group, gfp_t flags)
 963{
 964	int err;
 965
 966	NETLINK_CB(skb).dst_group = group;
 967
 968	err = netlink_broadcast(sk, skb, portid, group, flags);
 969	if (err > 0)
 970		err = 0;
 971
 972	return err;
 973}
 974
 975/**
 976 * nlmsg_unicast - unicast a netlink message
 977 * @sk: netlink socket to spread message to
 978 * @skb: netlink message as socket buffer
 979 * @portid: netlink portid of the destination socket
 980 */
 981static inline int nlmsg_unicast(struct sock *sk, struct sk_buff *skb, u32 portid)
 982{
 983	int err;
 984
 985	err = netlink_unicast(sk, skb, portid, MSG_DONTWAIT);
 986	if (err > 0)
 987		err = 0;
 988
 989	return err;
 990}
 991
 992/**
 993 * nlmsg_for_each_msg - iterate over a stream of messages
 994 * @pos: loop counter, set to current message
 995 * @head: head of message stream
 996 * @len: length of message stream
 997 * @rem: initialized to len, holds bytes currently remaining in stream
 998 */
 999#define nlmsg_for_each_msg(pos, head, len, rem) \
1000	for (pos = head, rem = len; \
1001	     nlmsg_ok(pos, rem); \
1002	     pos = nlmsg_next(pos, &(rem)))
1003
1004/**
1005 * nl_dump_check_consistent - check if sequence is consistent and advertise if not
1006 * @cb: netlink callback structure that stores the sequence number
1007 * @nlh: netlink message header to write the flag to
1008 *
1009 * This function checks if the sequence (generation) number changed during dump
1010 * and if it did, advertises it in the netlink message header.
1011 *
1012 * The correct way to use it is to set cb->seq to the generation counter when
1013 * all locks for dumping have been acquired, and then call this function for
1014 * each message that is generated.
1015 *
1016 * Note that due to initialisation concerns, 0 is an invalid sequence number
1017 * and must not be used by code that uses this functionality.
1018 */
1019static inline void
1020nl_dump_check_consistent(struct netlink_callback *cb,
1021			 struct nlmsghdr *nlh)
1022{
1023	if (cb->prev_seq && cb->seq != cb->prev_seq)
1024		nlh->nlmsg_flags |= NLM_F_DUMP_INTR;
1025	cb->prev_seq = cb->seq;
1026}
1027
1028/**************************************************************************
1029 * Netlink Attributes
1030 **************************************************************************/
1031
1032/**
1033 * nla_attr_size - length of attribute not including padding
1034 * @payload: length of payload
1035 */
1036static inline int nla_attr_size(int payload)
1037{
1038	return NLA_HDRLEN + payload;
1039}
1040
1041/**
1042 * nla_total_size - total length of attribute including padding
1043 * @payload: length of payload
1044 */
1045static inline int nla_total_size(int payload)
1046{
1047	return NLA_ALIGN(nla_attr_size(payload));
1048}
1049
1050/**
1051 * nla_padlen - length of padding at the tail of attribute
1052 * @payload: length of payload
1053 */
1054static inline int nla_padlen(int payload)
1055{
1056	return nla_total_size(payload) - nla_attr_size(payload);
1057}
1058
1059/**
1060 * nla_type - attribute type
1061 * @nla: netlink attribute
1062 */
1063static inline int nla_type(const struct nlattr *nla)
1064{
1065	return nla->nla_type & NLA_TYPE_MASK;
1066}
1067
1068/**
1069 * nla_data - head of payload
1070 * @nla: netlink attribute
1071 */
1072static inline void *nla_data(const struct nlattr *nla)
1073{
1074	return (char *) nla + NLA_HDRLEN;
1075}
1076
1077/**
1078 * nla_len - length of payload
1079 * @nla: netlink attribute
1080 */
1081static inline int nla_len(const struct nlattr *nla)
1082{
1083	return nla->nla_len - NLA_HDRLEN;
1084}
1085
1086/**
1087 * nla_ok - check if the netlink attribute fits into the remaining bytes
1088 * @nla: netlink attribute
1089 * @remaining: number of bytes remaining in attribute stream
1090 */
1091static inline int nla_ok(const struct nlattr *nla, int remaining)
1092{
1093	return remaining >= (int) sizeof(*nla) &&
1094	       nla->nla_len >= sizeof(*nla) &&
1095	       nla->nla_len <= remaining;
1096}
1097
1098/**
1099 * nla_next - next netlink attribute in attribute stream
1100 * @nla: netlink attribute
1101 * @remaining: number of bytes remaining in attribute stream
1102 *
1103 * Returns the next netlink attribute in the attribute stream and
1104 * decrements remaining by the size of the current attribute.
1105 */
1106static inline struct nlattr *nla_next(const struct nlattr *nla, int *remaining)
1107{
1108	unsigned int totlen = NLA_ALIGN(nla->nla_len);
1109
1110	*remaining -= totlen;
1111	return (struct nlattr *) ((char *) nla + totlen);
1112}
1113
1114/**
1115 * nla_find_nested - find attribute in a set of nested attributes
1116 * @nla: attribute containing the nested attributes
1117 * @attrtype: type of attribute to look for
1118 *
1119 * Returns the first attribute which matches the specified type.
1120 */
1121static inline struct nlattr *
1122nla_find_nested(const struct nlattr *nla, int attrtype)
1123{
1124	return nla_find(nla_data(nla), nla_len(nla), attrtype);
1125}
1126
1127/**
1128 * nla_parse_nested - parse nested attributes
1129 * @tb: destination array with maxtype+1 elements
1130 * @maxtype: maximum attribute type to be expected
1131 * @nla: attribute containing the nested attributes
1132 * @policy: validation policy
1133 * @extack: extended ACK report struct
1134 *
1135 * See nla_parse()
1136 */
1137static inline int nla_parse_nested(struct nlattr *tb[], int maxtype,
1138				   const struct nlattr *nla,
1139				   const struct nla_policy *policy,
1140				   struct netlink_ext_ack *extack)
1141{
1142	if (!(nla->nla_type & NLA_F_NESTED)) {
1143		NL_SET_ERR_MSG_ATTR(extack, nla, "NLA_F_NESTED is missing");
1144		return -EINVAL;
1145	}
1146
1147	return __nla_parse(tb, maxtype, nla_data(nla), nla_len(nla), policy,
1148			   NL_VALIDATE_STRICT, extack);
1149}
1150
1151/**
1152 * nla_parse_nested_deprecated - parse nested attributes
1153 * @tb: destination array with maxtype+1 elements
1154 * @maxtype: maximum attribute type to be expected
1155 * @nla: attribute containing the nested attributes
1156 * @policy: validation policy
1157 * @extack: extended ACK report struct
1158 *
1159 * See nla_parse_deprecated()
1160 */
1161static inline int nla_parse_nested_deprecated(struct nlattr *tb[], int maxtype,
1162					      const struct nlattr *nla,
1163					      const struct nla_policy *policy,
1164					      struct netlink_ext_ack *extack)
1165{
1166	return __nla_parse(tb, maxtype, nla_data(nla), nla_len(nla), policy,
1167			   NL_VALIDATE_LIBERAL, extack);
1168}
1169
1170/**
1171 * nla_put_u8 - Add a u8 netlink attribute to a socket buffer
1172 * @skb: socket buffer to add attribute to
1173 * @attrtype: attribute type
1174 * @value: numeric value
1175 */
1176static inline int nla_put_u8(struct sk_buff *skb, int attrtype, u8 value)
1177{
1178	/* temporary variables to work around GCC PR81715 with asan-stack=1 */
1179	u8 tmp = value;
1180
1181	return nla_put(skb, attrtype, sizeof(u8), &tmp);
1182}
1183
1184/**
1185 * nla_put_u16 - Add a u16 netlink attribute to a socket buffer
1186 * @skb: socket buffer to add attribute to
1187 * @attrtype: attribute type
1188 * @value: numeric value
1189 */
1190static inline int nla_put_u16(struct sk_buff *skb, int attrtype, u16 value)
1191{
1192	u16 tmp = value;
1193
1194	return nla_put(skb, attrtype, sizeof(u16), &tmp);
1195}
1196
1197/**
1198 * nla_put_be16 - Add a __be16 netlink attribute to a socket buffer
1199 * @skb: socket buffer to add attribute to
1200 * @attrtype: attribute type
1201 * @value: numeric value
1202 */
1203static inline int nla_put_be16(struct sk_buff *skb, int attrtype, __be16 value)
1204{
1205	__be16 tmp = value;
1206
1207	return nla_put(skb, attrtype, sizeof(__be16), &tmp);
1208}
1209
1210/**
1211 * nla_put_net16 - Add 16-bit network byte order netlink attribute to a socket buffer
1212 * @skb: socket buffer to add attribute to
1213 * @attrtype: attribute type
1214 * @value: numeric value
1215 */
1216static inline int nla_put_net16(struct sk_buff *skb, int attrtype, __be16 value)
1217{
1218	__be16 tmp = value;
1219
1220	return nla_put_be16(skb, attrtype | NLA_F_NET_BYTEORDER, tmp);
1221}
1222
1223/**
1224 * nla_put_le16 - Add a __le16 netlink attribute to a socket buffer
1225 * @skb: socket buffer to add attribute to
1226 * @attrtype: attribute type
1227 * @value: numeric value
1228 */
1229static inline int nla_put_le16(struct sk_buff *skb, int attrtype, __le16 value)
1230{
1231	__le16 tmp = value;
1232
1233	return nla_put(skb, attrtype, sizeof(__le16), &tmp);
1234}
1235
1236/**
1237 * nla_put_u32 - Add a u32 netlink attribute to a socket buffer
1238 * @skb: socket buffer to add attribute to
1239 * @attrtype: attribute type
1240 * @value: numeric value
1241 */
1242static inline int nla_put_u32(struct sk_buff *skb, int attrtype, u32 value)
1243{
1244	u32 tmp = value;
1245
1246	return nla_put(skb, attrtype, sizeof(u32), &tmp);
1247}
1248
1249/**
1250 * nla_put_be32 - Add a __be32 netlink attribute to a socket buffer
1251 * @skb: socket buffer to add attribute to
1252 * @attrtype: attribute type
1253 * @value: numeric value
1254 */
1255static inline int nla_put_be32(struct sk_buff *skb, int attrtype, __be32 value)
1256{
1257	__be32 tmp = value;
1258
1259	return nla_put(skb, attrtype, sizeof(__be32), &tmp);
1260}
1261
1262/**
1263 * nla_put_net32 - Add 32-bit network byte order netlink attribute to a socket buffer
1264 * @skb: socket buffer to add attribute to
1265 * @attrtype: attribute type
1266 * @value: numeric value
1267 */
1268static inline int nla_put_net32(struct sk_buff *skb, int attrtype, __be32 value)
1269{
1270	__be32 tmp = value;
1271
1272	return nla_put_be32(skb, attrtype | NLA_F_NET_BYTEORDER, tmp);
1273}
1274
1275/**
1276 * nla_put_le32 - Add a __le32 netlink attribute to a socket buffer
1277 * @skb: socket buffer to add attribute to
1278 * @attrtype: attribute type
1279 * @value: numeric value
1280 */
1281static inline int nla_put_le32(struct sk_buff *skb, int attrtype, __le32 value)
1282{
1283	__le32 tmp = value;
1284
1285	return nla_put(skb, attrtype, sizeof(__le32), &tmp);
1286}
1287
1288/**
1289 * nla_put_u64_64bit - Add a u64 netlink attribute to a skb and align it
1290 * @skb: socket buffer to add attribute to
1291 * @attrtype: attribute type
1292 * @value: numeric value
1293 * @padattr: attribute type for the padding
1294 */
1295static inline int nla_put_u64_64bit(struct sk_buff *skb, int attrtype,
1296				    u64 value, int padattr)
1297{
1298	u64 tmp = value;
1299
1300	return nla_put_64bit(skb, attrtype, sizeof(u64), &tmp, padattr);
1301}
1302
1303/**
1304 * nla_put_be64 - Add a __be64 netlink attribute to a socket buffer and align it
1305 * @skb: socket buffer to add attribute to
1306 * @attrtype: attribute type
1307 * @value: numeric value
1308 * @padattr: attribute type for the padding
1309 */
1310static inline int nla_put_be64(struct sk_buff *skb, int attrtype, __be64 value,
1311			       int padattr)
1312{
1313	__be64 tmp = value;
1314
1315	return nla_put_64bit(skb, attrtype, sizeof(__be64), &tmp, padattr);
1316}
1317
1318/**
1319 * nla_put_net64 - Add 64-bit network byte order nlattr to a skb and align it
1320 * @skb: socket buffer to add attribute to
1321 * @attrtype: attribute type
1322 * @value: numeric value
1323 * @padattr: attribute type for the padding
1324 */
1325static inline int nla_put_net64(struct sk_buff *skb, int attrtype, __be64 value,
1326				int padattr)
1327{
1328	__be64 tmp = value;
1329
1330	return nla_put_be64(skb, attrtype | NLA_F_NET_BYTEORDER, tmp,
1331			    padattr);
1332}
1333
1334/**
1335 * nla_put_le64 - Add a __le64 netlink attribute to a socket buffer and align it
1336 * @skb: socket buffer to add attribute to
1337 * @attrtype: attribute type
1338 * @value: numeric value
1339 * @padattr: attribute type for the padding
1340 */
1341static inline int nla_put_le64(struct sk_buff *skb, int attrtype, __le64 value,
1342			       int padattr)
1343{
1344	__le64 tmp = value;
1345
1346	return nla_put_64bit(skb, attrtype, sizeof(__le64), &tmp, padattr);
1347}
1348
1349/**
1350 * nla_put_s8 - Add a s8 netlink attribute to a socket buffer
1351 * @skb: socket buffer to add attribute to
1352 * @attrtype: attribute type
1353 * @value: numeric value
1354 */
1355static inline int nla_put_s8(struct sk_buff *skb, int attrtype, s8 value)
1356{
1357	s8 tmp = value;
1358
1359	return nla_put(skb, attrtype, sizeof(s8), &tmp);
1360}
1361
1362/**
1363 * nla_put_s16 - Add a s16 netlink attribute to a socket buffer
1364 * @skb: socket buffer to add attribute to
1365 * @attrtype: attribute type
1366 * @value: numeric value
1367 */
1368static inline int nla_put_s16(struct sk_buff *skb, int attrtype, s16 value)
1369{
1370	s16 tmp = value;
1371
1372	return nla_put(skb, attrtype, sizeof(s16), &tmp);
1373}
1374
1375/**
1376 * nla_put_s32 - Add a s32 netlink attribute to a socket buffer
1377 * @skb: socket buffer to add attribute to
1378 * @attrtype: attribute type
1379 * @value: numeric value
1380 */
1381static inline int nla_put_s32(struct sk_buff *skb, int attrtype, s32 value)
1382{
1383	s32 tmp = value;
1384
1385	return nla_put(skb, attrtype, sizeof(s32), &tmp);
1386}
1387
1388/**
1389 * nla_put_s64 - Add a s64 netlink attribute to a socket buffer and align it
1390 * @skb: socket buffer to add attribute to
1391 * @attrtype: attribute type
1392 * @value: numeric value
1393 * @padattr: attribute type for the padding
1394 */
1395static inline int nla_put_s64(struct sk_buff *skb, int attrtype, s64 value,
1396			      int padattr)
1397{
1398	s64 tmp = value;
1399
1400	return nla_put_64bit(skb, attrtype, sizeof(s64), &tmp, padattr);
1401}
1402
1403/**
1404 * nla_put_string - Add a string netlink attribute to a socket buffer
1405 * @skb: socket buffer to add attribute to
1406 * @attrtype: attribute type
1407 * @str: NUL terminated string
1408 */
1409static inline int nla_put_string(struct sk_buff *skb, int attrtype,
1410				 const char *str)
1411{
1412	return nla_put(skb, attrtype, strlen(str) + 1, str);
1413}
1414
1415/**
1416 * nla_put_flag - Add a flag netlink attribute to a socket buffer
1417 * @skb: socket buffer to add attribute to
1418 * @attrtype: attribute type
1419 */
1420static inline int nla_put_flag(struct sk_buff *skb, int attrtype)
1421{
1422	return nla_put(skb, attrtype, 0, NULL);
1423}
1424
1425/**
1426 * nla_put_msecs - Add a msecs netlink attribute to a skb and align it
1427 * @skb: socket buffer to add attribute to
1428 * @attrtype: attribute type
1429 * @njiffies: number of jiffies to convert to msecs
1430 * @padattr: attribute type for the padding
1431 */
1432static inline int nla_put_msecs(struct sk_buff *skb, int attrtype,
1433				unsigned long njiffies, int padattr)
1434{
1435	u64 tmp = jiffies_to_msecs(njiffies);
1436
1437	return nla_put_64bit(skb, attrtype, sizeof(u64), &tmp, padattr);
1438}
1439
1440/**
1441 * nla_put_in_addr - Add an IPv4 address netlink attribute to a socket
1442 * buffer
1443 * @skb: socket buffer to add attribute to
1444 * @attrtype: attribute type
1445 * @addr: IPv4 address
1446 */
1447static inline int nla_put_in_addr(struct sk_buff *skb, int attrtype,
1448				  __be32 addr)
1449{
1450	__be32 tmp = addr;
1451
1452	return nla_put_be32(skb, attrtype, tmp);
1453}
1454
1455/**
1456 * nla_put_in6_addr - Add an IPv6 address netlink attribute to a socket
1457 * buffer
1458 * @skb: socket buffer to add attribute to
1459 * @attrtype: attribute type
1460 * @addr: IPv6 address
1461 */
1462static inline int nla_put_in6_addr(struct sk_buff *skb, int attrtype,
1463				   const struct in6_addr *addr)
1464{
1465	return nla_put(skb, attrtype, sizeof(*addr), addr);
1466}
1467
1468/**
1469 * nla_get_u32 - return payload of u32 attribute
1470 * @nla: u32 netlink attribute
1471 */
1472static inline u32 nla_get_u32(const struct nlattr *nla)
1473{
1474	return *(u32 *) nla_data(nla);
1475}
1476
1477/**
1478 * nla_get_be32 - return payload of __be32 attribute
1479 * @nla: __be32 netlink attribute
1480 */
1481static inline __be32 nla_get_be32(const struct nlattr *nla)
1482{
1483	return *(__be32 *) nla_data(nla);
1484}
1485
1486/**
1487 * nla_get_le32 - return payload of __le32 attribute
1488 * @nla: __le32 netlink attribute
1489 */
1490static inline __le32 nla_get_le32(const struct nlattr *nla)
1491{
1492	return *(__le32 *) nla_data(nla);
1493}
1494
1495/**
1496 * nla_get_u16 - return payload of u16 attribute
1497 * @nla: u16 netlink attribute
1498 */
1499static inline u16 nla_get_u16(const struct nlattr *nla)
1500{
1501	return *(u16 *) nla_data(nla);
1502}
1503
1504/**
1505 * nla_get_be16 - return payload of __be16 attribute
1506 * @nla: __be16 netlink attribute
1507 */
1508static inline __be16 nla_get_be16(const struct nlattr *nla)
1509{
1510	return *(__be16 *) nla_data(nla);
1511}
1512
1513/**
1514 * nla_get_le16 - return payload of __le16 attribute
1515 * @nla: __le16 netlink attribute
1516 */
1517static inline __le16 nla_get_le16(const struct nlattr *nla)
1518{
1519	return *(__le16 *) nla_data(nla);
1520}
1521
1522/**
1523 * nla_get_u8 - return payload of u8 attribute
1524 * @nla: u8 netlink attribute
1525 */
1526static inline u8 nla_get_u8(const struct nlattr *nla)
1527{
1528	return *(u8 *) nla_data(nla);
1529}
1530
1531/**
1532 * nla_get_u64 - return payload of u64 attribute
1533 * @nla: u64 netlink attribute
1534 */
1535static inline u64 nla_get_u64(const struct nlattr *nla)
1536{
1537	u64 tmp;
1538
1539	nla_memcpy(&tmp, nla, sizeof(tmp));
1540
1541	return tmp;
1542}
1543
1544/**
1545 * nla_get_be64 - return payload of __be64 attribute
1546 * @nla: __be64 netlink attribute
1547 */
1548static inline __be64 nla_get_be64(const struct nlattr *nla)
1549{
1550	__be64 tmp;
1551
1552	nla_memcpy(&tmp, nla, sizeof(tmp));
1553
1554	return tmp;
1555}
1556
1557/**
1558 * nla_get_le64 - return payload of __le64 attribute
1559 * @nla: __le64 netlink attribute
1560 */
1561static inline __le64 nla_get_le64(const struct nlattr *nla)
1562{
1563	return *(__le64 *) nla_data(nla);
1564}
1565
1566/**
1567 * nla_get_s32 - return payload of s32 attribute
1568 * @nla: s32 netlink attribute
1569 */
1570static inline s32 nla_get_s32(const struct nlattr *nla)
1571{
1572	return *(s32 *) nla_data(nla);
1573}
1574
1575/**
1576 * nla_get_s16 - return payload of s16 attribute
1577 * @nla: s16 netlink attribute
1578 */
1579static inline s16 nla_get_s16(const struct nlattr *nla)
1580{
1581	return *(s16 *) nla_data(nla);
1582}
1583
1584/**
1585 * nla_get_s8 - return payload of s8 attribute
1586 * @nla: s8 netlink attribute
1587 */
1588static inline s8 nla_get_s8(const struct nlattr *nla)
1589{
1590	return *(s8 *) nla_data(nla);
1591}
1592
1593/**
1594 * nla_get_s64 - return payload of s64 attribute
1595 * @nla: s64 netlink attribute
1596 */
1597static inline s64 nla_get_s64(const struct nlattr *nla)
1598{
1599	s64 tmp;
1600
1601	nla_memcpy(&tmp, nla, sizeof(tmp));
1602
1603	return tmp;
1604}
1605
1606/**
1607 * nla_get_flag - return payload of flag attribute
1608 * @nla: flag netlink attribute
1609 */
1610static inline int nla_get_flag(const struct nlattr *nla)
1611{
1612	return !!nla;
1613}
1614
1615/**
1616 * nla_get_msecs - return payload of msecs attribute
1617 * @nla: msecs netlink attribute
1618 *
1619 * Returns the number of milliseconds in jiffies.
1620 */
1621static inline unsigned long nla_get_msecs(const struct nlattr *nla)
1622{
1623	u64 msecs = nla_get_u64(nla);
1624
1625	return msecs_to_jiffies((unsigned long) msecs);
1626}
1627
1628/**
1629 * nla_get_in_addr - return payload of IPv4 address attribute
1630 * @nla: IPv4 address netlink attribute
1631 */
1632static inline __be32 nla_get_in_addr(const struct nlattr *nla)
1633{
1634	return *(__be32 *) nla_data(nla);
1635}
1636
1637/**
1638 * nla_get_in6_addr - return payload of IPv6 address attribute
1639 * @nla: IPv6 address netlink attribute
1640 */
1641static inline struct in6_addr nla_get_in6_addr(const struct nlattr *nla)
1642{
1643	struct in6_addr tmp;
1644
1645	nla_memcpy(&tmp, nla, sizeof(tmp));
1646	return tmp;
1647}
1648
1649/**
1650 * nla_get_bitfield32 - return payload of 32 bitfield attribute
1651 * @nla: nla_bitfield32 attribute
1652 */
1653static inline struct nla_bitfield32 nla_get_bitfield32(const struct nlattr *nla)
1654{
1655	struct nla_bitfield32 tmp;
1656
1657	nla_memcpy(&tmp, nla, sizeof(tmp));
1658	return tmp;
1659}
1660
1661/**
1662 * nla_memdup - duplicate attribute memory (kmemdup)
1663 * @src: netlink attribute to duplicate from
1664 * @gfp: GFP mask
1665 */
1666static inline void *nla_memdup(const struct nlattr *src, gfp_t gfp)
1667{
1668	return kmemdup(nla_data(src), nla_len(src), gfp);
1669}
1670
1671/**
1672 * nla_nest_start_noflag - Start a new level of nested attributes
1673 * @skb: socket buffer to add attributes to
1674 * @attrtype: attribute type of container
1675 *
1676 * This function exists for backward compatibility to use in APIs which never
1677 * marked their nest attributes with NLA_F_NESTED flag. New APIs should use
1678 * nla_nest_start() which sets the flag.
1679 *
1680 * Returns the container attribute or NULL on error
1681 */
1682static inline struct nlattr *nla_nest_start_noflag(struct sk_buff *skb,
1683						   int attrtype)
1684{
1685	struct nlattr *start = (struct nlattr *)skb_tail_pointer(skb);
1686
1687	if (nla_put(skb, attrtype, 0, NULL) < 0)
1688		return NULL;
1689
1690	return start;
1691}
1692
1693/**
1694 * nla_nest_start - Start a new level of nested attributes, with NLA_F_NESTED
1695 * @skb: socket buffer to add attributes to
1696 * @attrtype: attribute type of container
1697 *
1698 * Unlike nla_nest_start_noflag(), mark the nest attribute with NLA_F_NESTED
1699 * flag. This is the preferred function to use in new code.
1700 *
1701 * Returns the container attribute or NULL on error
1702 */
1703static inline struct nlattr *nla_nest_start(struct sk_buff *skb, int attrtype)
1704{
1705	return nla_nest_start_noflag(skb, attrtype | NLA_F_NESTED);
1706}
1707
1708/**
1709 * nla_nest_end - Finalize nesting of attributes
1710 * @skb: socket buffer the attributes are stored in
1711 * @start: container attribute
1712 *
1713 * Corrects the container attribute header to include the all
1714 * appeneded attributes.
1715 *
1716 * Returns the total data length of the skb.
1717 */
1718static inline int nla_nest_end(struct sk_buff *skb, struct nlattr *start)
1719{
1720	start->nla_len = skb_tail_pointer(skb) - (unsigned char *)start;
1721	return skb->len;
1722}
1723
1724/**
1725 * nla_nest_cancel - Cancel nesting of attributes
1726 * @skb: socket buffer the message is stored in
1727 * @start: container attribute
1728 *
1729 * Removes the container attribute and including all nested
1730 * attributes. Returns -EMSGSIZE
1731 */
1732static inline void nla_nest_cancel(struct sk_buff *skb, struct nlattr *start)
1733{
1734	nlmsg_trim(skb, start);
1735}
1736
1737/**
1738 * nla_validate_nested - Validate a stream of nested attributes
1739 * @start: container attribute
1740 * @maxtype: maximum attribute type to be expected
1741 * @policy: validation policy
1742 * @validate: validation strictness
1743 * @extack: extended ACK report struct
1744 *
1745 * Validates all attributes in the nested attribute stream against the
1746 * specified policy. Attributes with a type exceeding maxtype will be
1747 * ignored. See documenation of struct nla_policy for more details.
1748 *
1749 * Returns 0 on success or a negative error code.
1750 */
1751static inline int __nla_validate_nested(const struct nlattr *start, int maxtype,
1752					const struct nla_policy *policy,
1753					unsigned int validate,
1754					struct netlink_ext_ack *extack)
1755{
1756	return __nla_validate(nla_data(start), nla_len(start), maxtype, policy,
1757			      validate, extack);
1758}
1759
1760static inline int
1761nl80211_validate_nested(const struct nlattr *start, int maxtype,
1762			const struct nla_policy *policy,
1763			struct netlink_ext_ack *extack)
1764{
1765	return __nla_validate_nested(start, maxtype, policy,
1766				     NL_VALIDATE_STRICT, extack);
1767}
1768
1769static inline int
1770nla_validate_nested_deprecated(const struct nlattr *start, int maxtype,
1771			       const struct nla_policy *policy,
1772			       struct netlink_ext_ack *extack)
1773{
1774	return __nla_validate_nested(start, maxtype, policy,
1775				     NL_VALIDATE_LIBERAL, extack);
1776}
1777
1778/**
1779 * nla_need_padding_for_64bit - test 64-bit alignment of the next attribute
1780 * @skb: socket buffer the message is stored in
1781 *
1782 * Return true if padding is needed to align the next attribute (nla_data()) to
1783 * a 64-bit aligned area.
1784 */
1785static inline bool nla_need_padding_for_64bit(struct sk_buff *skb)
1786{
1787#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1788	/* The nlattr header is 4 bytes in size, that's why we test
1789	 * if the skb->data _is_ aligned.  A NOP attribute, plus
1790	 * nlattr header for next attribute, will make nla_data()
1791	 * 8-byte aligned.
1792	 */
1793	if (IS_ALIGNED((unsigned long)skb_tail_pointer(skb), 8))
1794		return true;
1795#endif
1796	return false;
1797}
1798
1799/**
1800 * nla_align_64bit - 64-bit align the nla_data() of next attribute
1801 * @skb: socket buffer the message is stored in
1802 * @padattr: attribute type for the padding
1803 *
1804 * Conditionally emit a padding netlink attribute in order to make
1805 * the next attribute we emit have a 64-bit aligned nla_data() area.
1806 * This will only be done in architectures which do not have
1807 * CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS defined.
1808 *
1809 * Returns zero on success or a negative error code.
1810 */
1811static inline int nla_align_64bit(struct sk_buff *skb, int padattr)
1812{
1813	if (nla_need_padding_for_64bit(skb) &&
1814	    !nla_reserve(skb, padattr, 0))
1815		return -EMSGSIZE;
1816
1817	return 0;
1818}
1819
1820/**
1821 * nla_total_size_64bit - total length of attribute including padding
1822 * @payload: length of payload
1823 */
1824static inline int nla_total_size_64bit(int payload)
1825{
1826	return NLA_ALIGN(nla_attr_size(payload))
1827#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1828		+ NLA_ALIGN(nla_attr_size(0))
1829#endif
1830		;
1831}
1832
1833/**
1834 * nla_for_each_attr - iterate over a stream of attributes
1835 * @pos: loop counter, set to current attribute
1836 * @head: head of attribute stream
1837 * @len: length of attribute stream
1838 * @rem: initialized to len, holds bytes currently remaining in stream
1839 */
1840#define nla_for_each_attr(pos, head, len, rem) \
1841	for (pos = head, rem = len; \
1842	     nla_ok(pos, rem); \
1843	     pos = nla_next(pos, &(rem)))
1844
1845/**
1846 * nla_for_each_nested - iterate over nested attributes
1847 * @pos: loop counter, set to current attribute
1848 * @nla: attribute containing the nested attributes
1849 * @rem: initialized to len, holds bytes currently remaining in stream
1850 */
1851#define nla_for_each_nested(pos, nla, rem) \
1852	nla_for_each_attr(pos, nla_data(nla), nla_len(nla), rem)
1853
1854/**
1855 * nla_is_last - Test if attribute is last in stream
1856 * @nla: attribute to test
1857 * @rem: bytes remaining in stream
1858 */
1859static inline bool nla_is_last(const struct nlattr *nla, int rem)
1860{
1861	return nla->nla_len == rem;
1862}
1863
1864#endif