1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _NET_NF_TABLES_H
3 #define _NET_NF_TABLES_H
4 
5 #include <linux/unaligned.h>
6 #include <linux/list.h>
7 #include <linux/netfilter.h>
8 #include <linux/netfilter/nfnetlink.h>
9 #include <linux/netfilter/x_tables.h>
10 #include <linux/netfilter/nf_tables.h>
11 #include <linux/u64_stats_sync.h>
12 #include <linux/rhashtable.h>
13 #include <net/netfilter/nf_flow_table.h>
14 #include <net/netlink.h>
15 #include <net/flow_offload.h>
16 #include <net/netns/generic.h>
17 
18 #define NFT_MAX_HOOKS	(NF_INET_INGRESS + 1)
19 
20 struct module;
21 
22 #define NFT_JUMP_STACK_SIZE	16
23 
24 enum {
25 	NFT_PKTINFO_L4PROTO	= (1 << 0),
26 	NFT_PKTINFO_INNER	= (1 << 1),
27 	NFT_PKTINFO_INNER_FULL	= (1 << 2),
28 };
29 
30 struct nft_pktinfo {
31 	struct sk_buff			*skb;
32 	const struct nf_hook_state	*state;
33 	u8				flags;
34 	u8				tprot;
35 	u16				fragoff;
36 	u16				thoff;
37 	u16				inneroff;
38 };
39 
40 static inline struct sock *nft_sk(const struct nft_pktinfo *pkt)
41 {
42 	return pkt->state->sk;
43 }
44 
45 static inline unsigned int nft_thoff(const struct nft_pktinfo *pkt)
46 {
47 	return pkt->thoff;
48 }
49 
50 static inline struct net *nft_net(const struct nft_pktinfo *pkt)
51 {
52 	return pkt->state->net;
53 }
54 
55 static inline unsigned int nft_hook(const struct nft_pktinfo *pkt)
56 {
57 	return pkt->state->hook;
58 }
59 
60 static inline u8 nft_pf(const struct nft_pktinfo *pkt)
61 {
62 	return pkt->state->pf;
63 }
64 
65 static inline const struct net_device *nft_in(const struct nft_pktinfo *pkt)
66 {
67 	return pkt->state->in;
68 }
69 
70 static inline const struct net_device *nft_out(const struct nft_pktinfo *pkt)
71 {
72 	return pkt->state->out;
73 }
74 
75 static inline void nft_set_pktinfo(struct nft_pktinfo *pkt,
76 				   struct sk_buff *skb,
77 				   const struct nf_hook_state *state)
78 {
79 	pkt->skb = skb;
80 	pkt->state = state;
81 }
82 
83 static inline void nft_set_pktinfo_unspec(struct nft_pktinfo *pkt)
84 {
85 	pkt->flags = 0;
86 	pkt->tprot = 0;
87 	pkt->thoff = 0;
88 	pkt->fragoff = 0;
89 }
90 
91 /**
92  * 	struct nft_verdict - nf_tables verdict
93  *
94  * 	@code: nf_tables/netfilter verdict code
95  * 	@chain: destination chain for NFT_JUMP/NFT_GOTO
96  */
97 struct nft_verdict {
98 	u32				code;
99 	struct nft_chain		*chain;
100 };
101 
102 struct nft_data {
103 	union {
104 		u32			data[4];
105 		struct nft_verdict	verdict;
106 	};
107 } __attribute__((aligned(__alignof__(u64))));
108 
109 #define NFT_REG32_NUM		20
110 
111 /**
112  *	struct nft_regs - nf_tables register set
113  *
114  *	@data: data registers
115  *	@verdict: verdict register
116  *
117  *	The first four data registers alias to the verdict register.
118  */
119 struct nft_regs {
120 	union {
121 		u32			data[NFT_REG32_NUM];
122 		struct nft_verdict	verdict;
123 	};
124 };
125 
126 struct nft_regs_track {
127 	struct {
128 		const struct nft_expr		*selector;
129 		const struct nft_expr		*bitwise;
130 		u8				num_reg;
131 	} regs[NFT_REG32_NUM];
132 
133 	const struct nft_expr			*cur;
134 	const struct nft_expr			*last;
135 };
136 
137 /* Store/load an u8, u16 or u64 integer to/from the u32 data register.
138  *
139  * Note, when using concatenations, register allocation happens at 32-bit
140  * level. So for store instruction, pad the rest part with zero to avoid
141  * garbage values.
142  */
143 
144 static inline void nft_reg_store8(u32 *dreg, u8 val)
145 {
146 	*dreg = 0;
147 	*(u8 *)dreg = val;
148 }
149 
150 static inline u8 nft_reg_load8(const u32 *sreg)
151 {
152 	return *(u8 *)sreg;
153 }
154 
155 static inline void nft_reg_store16(u32 *dreg, u16 val)
156 {
157 	*dreg = 0;
158 	*(u16 *)dreg = val;
159 }
160 
161 static inline void nft_reg_store_be16(u32 *dreg, __be16 val)
162 {
163 	nft_reg_store16(dreg, (__force __u16)val);
164 }
165 
166 static inline u16 nft_reg_load16(const u32 *sreg)
167 {
168 	return *(u16 *)sreg;
169 }
170 
171 static inline __be16 nft_reg_load_be16(const u32 *sreg)
172 {
173 	return (__force __be16)nft_reg_load16(sreg);
174 }
175 
176 static inline __be32 nft_reg_load_be32(const u32 *sreg)
177 {
178 	return *(__force __be32 *)sreg;
179 }
180 
181 static inline void nft_reg_store64(u64 *dreg, u64 val)
182 {
183 	put_unaligned(val, dreg);
184 }
185 
186 static inline u64 nft_reg_load64(const u32 *sreg)
187 {
188 	return get_unaligned((u64 *)sreg);
189 }
190 
191 static inline void nft_data_copy(u32 *dst, const struct nft_data *src,
192 				 unsigned int len)
193 {
194 	if (len % NFT_REG32_SIZE)
195 		dst[len / NFT_REG32_SIZE] = 0;
196 	memcpy(dst, src, len);
197 }
198 
199 /**
200  *	struct nft_ctx - nf_tables rule/set context
201  *
202  *	@net: net namespace
203  * 	@table: the table the chain is contained in
204  * 	@chain: the chain the rule is contained in
205  *	@nla: netlink attributes
206  *	@portid: netlink portID of the original message
207  *	@seq: netlink sequence number
208  *	@flags: modifiers to new request
209  *	@family: protocol family
210  *	@level: depth of the chains
211  *	@report: notify via unicast netlink message
212  *	@reg_inited: bitmap of initialised registers
213  */
214 struct nft_ctx {
215 	struct net			*net;
216 	struct nft_table		*table;
217 	struct nft_chain		*chain;
218 	const struct nlattr * const 	*nla;
219 	u32				portid;
220 	u32				seq;
221 	u16				flags;
222 	u8				family;
223 	u8				level;
224 	bool				report;
225 	DECLARE_BITMAP(reg_inited, NFT_REG32_NUM);
226 };
227 
228 enum nft_data_desc_flags {
229 	NFT_DATA_DESC_SETELEM	= (1 << 0),
230 };
231 
232 struct nft_data_desc {
233 	enum nft_data_types		type;
234 	unsigned int			size;
235 	unsigned int			len;
236 	unsigned int			flags;
237 };
238 
239 int nft_data_init(const struct nft_ctx *ctx, struct nft_data *data,
240 		  struct nft_data_desc *desc, const struct nlattr *nla);
241 void nft_data_hold(const struct nft_data *data, enum nft_data_types type);
242 void nft_data_release(const struct nft_data *data, enum nft_data_types type);
243 int nft_data_dump(struct sk_buff *skb, int attr, const struct nft_data *data,
244 		  enum nft_data_types type, unsigned int len);
245 
246 static inline enum nft_data_types nft_dreg_to_type(enum nft_registers reg)
247 {
248 	return reg == NFT_REG_VERDICT ? NFT_DATA_VERDICT : NFT_DATA_VALUE;
249 }
250 
251 static inline enum nft_registers nft_type_to_reg(enum nft_data_types type)
252 {
253 	return type == NFT_DATA_VERDICT ? NFT_REG_VERDICT : NFT_REG_1 * NFT_REG_SIZE / NFT_REG32_SIZE;
254 }
255 
256 int nft_parse_u32_check(const struct nlattr *attr, int max, u32 *dest);
257 int nft_dump_register(struct sk_buff *skb, unsigned int attr, unsigned int reg);
258 
259 int nft_parse_register_load(const struct nft_ctx *ctx,
260 			    const struct nlattr *attr, u8 *sreg, u32 len);
261 int nft_parse_register_store(const struct nft_ctx *ctx,
262 			     const struct nlattr *attr, u8 *dreg,
263 			     const struct nft_data *data,
264 			     enum nft_data_types type, unsigned int len);
265 
266 /**
267  *	struct nft_userdata - user defined data associated with an object
268  *
269  *	@len: length of the data
270  *	@data: content
271  *
272  *	The presence of user data is indicated in an object specific fashion,
273  *	so a length of zero can't occur and the value "len" indicates data
274  *	of length len + 1.
275  */
276 struct nft_userdata {
277 	u8			len;
278 	unsigned char		data[];
279 };
280 
281 /* placeholder structure for opaque set element backend representation. */
282 struct nft_elem_priv { };
283 
284 /**
285  *	struct nft_set_elem - generic representation of set elements
286  *
287  *	@key: element key
288  *	@key_end: closing element key
289  *	@data: element data
290  *	@priv: element private data and extensions
291  */
292 struct nft_set_elem {
293 	union {
294 		u32		buf[NFT_DATA_VALUE_MAXLEN / sizeof(u32)];
295 		struct nft_data	val;
296 	} key;
297 	union {
298 		u32		buf[NFT_DATA_VALUE_MAXLEN / sizeof(u32)];
299 		struct nft_data	val;
300 	} key_end;
301 	union {
302 		u32		buf[NFT_DATA_VALUE_MAXLEN / sizeof(u32)];
303 		struct nft_data val;
304 	} data;
305 	struct nft_elem_priv	*priv;
306 };
307 
308 static inline void *nft_elem_priv_cast(const struct nft_elem_priv *priv)
309 {
310 	return (void *)priv;
311 }
312 
313 
314 /**
315  * enum nft_iter_type - nftables set iterator type
316  *
317  * @NFT_ITER_UNSPEC: unspecified, to catch errors
318  * @NFT_ITER_READ: read-only iteration over set elements
319  * @NFT_ITER_UPDATE: iteration under mutex to update set element state
320  */
321 enum nft_iter_type {
322 	NFT_ITER_UNSPEC,
323 	NFT_ITER_READ,
324 	NFT_ITER_UPDATE,
325 };
326 
327 struct nft_set;
328 struct nft_set_iter {
329 	u8		genmask;
330 	enum nft_iter_type type:8;
331 	unsigned int	count;
332 	unsigned int	skip;
333 	int		err;
334 	int		(*fn)(const struct nft_ctx *ctx,
335 			      struct nft_set *set,
336 			      const struct nft_set_iter *iter,
337 			      struct nft_elem_priv *elem_priv);
338 };
339 
340 /**
341  *	struct nft_set_desc - description of set elements
342  *
343  *	@ktype: key type
344  *	@klen: key length
345  *	@dtype: data type
346  *	@dlen: data length
347  *	@objtype: object type
348  *	@size: number of set elements
349  *	@policy: set policy
350  *	@gc_int: garbage collector interval
351  *	@timeout: element timeout
352  *	@field_len: length of each field in concatenation, bytes
353  *	@field_count: number of concatenated fields in element
354  *	@expr: set must support for expressions
355  */
356 struct nft_set_desc {
357 	u32			ktype;
358 	unsigned int		klen;
359 	u32			dtype;
360 	unsigned int		dlen;
361 	u32			objtype;
362 	unsigned int		size;
363 	u32			policy;
364 	u32			gc_int;
365 	u64			timeout;
366 	u8			field_len[NFT_REG32_COUNT];
367 	u8			field_count;
368 	bool			expr;
369 };
370 
371 /**
372  *	enum nft_set_class - performance class
373  *
374  *	@NFT_SET_CLASS_O_1: constant, O(1)
375  *	@NFT_SET_CLASS_O_LOG_N: logarithmic, O(log N)
376  *	@NFT_SET_CLASS_O_N: linear, O(N)
377  */
378 enum nft_set_class {
379 	NFT_SET_CLASS_O_1,
380 	NFT_SET_CLASS_O_LOG_N,
381 	NFT_SET_CLASS_O_N,
382 };
383 
384 /**
385  *	struct nft_set_estimate - estimation of memory and performance
386  *				  characteristics
387  *
388  *	@size: required memory
389  *	@lookup: lookup performance class
390  *	@space: memory class
391  */
392 struct nft_set_estimate {
393 	u64			size;
394 	enum nft_set_class	lookup;
395 	enum nft_set_class	space;
396 };
397 
398 #define NFT_EXPR_MAXATTR		16
399 #define NFT_EXPR_SIZE(size)		(sizeof(struct nft_expr) + \
400 					 ALIGN(size, __alignof__(struct nft_expr)))
401 
402 /**
403  *	struct nft_expr - nf_tables expression
404  *
405  *	@ops: expression ops
406  *	@data: expression private data
407  */
408 struct nft_expr {
409 	const struct nft_expr_ops	*ops;
410 	unsigned char			data[]
411 		__attribute__((aligned(__alignof__(u64))));
412 };
413 
414 static inline void *nft_expr_priv(const struct nft_expr *expr)
415 {
416 	return (void *)expr->data;
417 }
418 
419 struct nft_expr_info;
420 
421 int nft_expr_inner_parse(const struct nft_ctx *ctx, const struct nlattr *nla,
422 			 struct nft_expr_info *info);
423 int nft_expr_clone(struct nft_expr *dst, struct nft_expr *src, gfp_t gfp);
424 void nft_expr_destroy(const struct nft_ctx *ctx, struct nft_expr *expr);
425 int nft_expr_dump(struct sk_buff *skb, unsigned int attr,
426 		  const struct nft_expr *expr, bool reset);
427 bool nft_expr_reduce_bitwise(struct nft_regs_track *track,
428 			     const struct nft_expr *expr);
429 
430 struct nft_set_ext;
431 
432 /**
433  *	struct nft_set_ops - nf_tables set operations
434  *
435  *	@lookup: look up an element within the set
436  *	@update: update an element if exists, add it if doesn't exist
437  *	@delete: delete an element
438  *	@insert: insert new element into set
439  *	@activate: activate new element in the next generation
440  *	@deactivate: lookup for element and deactivate it in the next generation
441  *	@flush: deactivate element in the next generation
442  *	@remove: remove element from set
443  *	@walk: iterate over all set elements
444  *	@get: get set elements
445  *	@ksize: kernel set size
446  * 	@usize: userspace set size
447  *	@adjust_maxsize: delta to adjust maximum set size
448  *	@commit: commit set elements
449  *	@abort: abort set elements
450  *	@privsize: function to return size of set private data
451  *	@estimate: estimate the required memory size and the lookup complexity class
452  *	@init: initialize private data of new set instance
453  *	@destroy: destroy private data of set instance
454  *	@gc_init: initialize garbage collection
455  *	@elemsize: element private size
456  *
457  *	Operations lookup, update and delete have simpler interfaces, are faster
458  *	and currently only used in the packet path. All the rest are slower,
459  *	control plane functions.
460  */
461 struct nft_set_ops {
462 	bool				(*lookup)(const struct net *net,
463 						  const struct nft_set *set,
464 						  const u32 *key,
465 						  const struct nft_set_ext **ext);
466 	bool				(*update)(struct nft_set *set,
467 						  const u32 *key,
468 						  struct nft_elem_priv *
469 							(*new)(struct nft_set *,
470 							       const struct nft_expr *,
471 							       struct nft_regs *),
472 						  const struct nft_expr *expr,
473 						  struct nft_regs *regs,
474 						  const struct nft_set_ext **ext);
475 	bool				(*delete)(const struct nft_set *set,
476 						  const u32 *key);
477 
478 	int				(*insert)(const struct net *net,
479 						  const struct nft_set *set,
480 						  const struct nft_set_elem *elem,
481 						  struct nft_elem_priv **priv);
482 	void				(*activate)(const struct net *net,
483 						    const struct nft_set *set,
484 						    struct nft_elem_priv *elem_priv);
485 	struct nft_elem_priv *		(*deactivate)(const struct net *net,
486 						      const struct nft_set *set,
487 						      const struct nft_set_elem *elem);
488 	void				(*flush)(const struct net *net,
489 						 const struct nft_set *set,
490 						 struct nft_elem_priv *priv);
491 	void				(*remove)(const struct net *net,
492 						  const struct nft_set *set,
493 						  struct nft_elem_priv *elem_priv);
494 	void				(*walk)(const struct nft_ctx *ctx,
495 						struct nft_set *set,
496 						struct nft_set_iter *iter);
497 	struct nft_elem_priv *		(*get)(const struct net *net,
498 					       const struct nft_set *set,
499 					       const struct nft_set_elem *elem,
500 					       unsigned int flags);
501 	u32				(*ksize)(u32 size);
502 	u32				(*usize)(u32 size);
503 	u32				(*adjust_maxsize)(const struct nft_set *set);
504 	void				(*commit)(struct nft_set *set);
505 	void				(*abort)(const struct nft_set *set);
506 	u64				(*privsize)(const struct nlattr * const nla[],
507 						    const struct nft_set_desc *desc);
508 	bool				(*estimate)(const struct nft_set_desc *desc,
509 						    u32 features,
510 						    struct nft_set_estimate *est);
511 	int				(*init)(const struct nft_set *set,
512 						const struct nft_set_desc *desc,
513 						const struct nlattr * const nla[]);
514 	void				(*destroy)(const struct nft_ctx *ctx,
515 						   const struct nft_set *set);
516 	void				(*gc_init)(const struct nft_set *set);
517 
518 	unsigned int			elemsize;
519 };
520 
521 /**
522  *      struct nft_set_type - nf_tables set type
523  *
524  *      @ops: set ops for this type
525  *      @features: features supported by the implementation
526  */
527 struct nft_set_type {
528 	const struct nft_set_ops	ops;
529 	u32				features;
530 };
531 #define to_set_type(o) container_of(o, struct nft_set_type, ops)
532 
533 struct nft_set_elem_expr {
534 	u8				size;
535 	unsigned char			data[]
536 		__attribute__((aligned(__alignof__(struct nft_expr))));
537 };
538 
539 #define nft_setelem_expr_at(__elem_expr, __offset)			\
540 	((struct nft_expr *)&__elem_expr->data[__offset])
541 
542 #define nft_setelem_expr_foreach(__expr, __elem_expr, __size)		\
543 	for (__expr = nft_setelem_expr_at(__elem_expr, 0), __size = 0;	\
544 	     __size < (__elem_expr)->size;				\
545 	     __size += (__expr)->ops->size, __expr = ((void *)(__expr)) + (__expr)->ops->size)
546 
547 #define NFT_SET_EXPR_MAX	2
548 
549 /**
550  * 	struct nft_set - nf_tables set instance
551  *
552  *	@list: table set list node
553  *	@bindings: list of set bindings
554  *	@refs: internal refcounting for async set destruction
555  *	@table: table this set belongs to
556  *	@net: netnamespace this set belongs to
557  * 	@name: name of the set
558  *	@handle: unique handle of the set
559  * 	@ktype: key type (numeric type defined by userspace, not used in the kernel)
560  * 	@dtype: data type (verdict or numeric type defined by userspace)
561  * 	@objtype: object type (see NFT_OBJECT_* definitions)
562  * 	@size: maximum set size
563  *	@field_len: length of each field in concatenation, bytes
564  *	@field_count: number of concatenated fields in element
565  *	@use: number of rules references to this set
566  * 	@nelems: number of elements
567  * 	@ndeact: number of deactivated elements queued for removal
568  *	@timeout: default timeout value in jiffies
569  * 	@gc_int: garbage collection interval in msecs
570  *	@policy: set parameterization (see enum nft_set_policies)
571  *	@udlen: user data length
572  *	@udata: user data
573  *	@pending_update: list of pending update set element
574  * 	@ops: set ops
575  * 	@flags: set flags
576  *	@dead: set will be freed, never cleared
577  *	@genmask: generation mask
578  * 	@klen: key length
579  * 	@dlen: data length
580  *	@num_exprs: numbers of exprs
581  *	@exprs: stateful expression
582  *	@catchall_list: list of catch-all set element
583  * 	@data: private set data
584  */
585 struct nft_set {
586 	struct list_head		list;
587 	struct list_head		bindings;
588 	refcount_t			refs;
589 	struct nft_table		*table;
590 	possible_net_t			net;
591 	char				*name;
592 	u64				handle;
593 	u32				ktype;
594 	u32				dtype;
595 	u32				objtype;
596 	u32				size;
597 	u8				field_len[NFT_REG32_COUNT];
598 	u8				field_count;
599 	u32				use;
600 	atomic_t			nelems;
601 	u32				ndeact;
602 	u64				timeout;
603 	u32				gc_int;
604 	u16				policy;
605 	u16				udlen;
606 	unsigned char			*udata;
607 	struct list_head		pending_update;
608 	/* runtime data below here */
609 	const struct nft_set_ops	*ops ____cacheline_aligned;
610 	u16				flags:13,
611 					dead:1,
612 					genmask:2;
613 	u8				klen;
614 	u8				dlen;
615 	u8				num_exprs;
616 	struct nft_expr			*exprs[NFT_SET_EXPR_MAX];
617 	struct list_head		catchall_list;
618 	unsigned char			data[]
619 		__attribute__((aligned(__alignof__(u64))));
620 };
621 
622 static inline bool nft_set_is_anonymous(const struct nft_set *set)
623 {
624 	return set->flags & NFT_SET_ANONYMOUS;
625 }
626 
627 static inline void *nft_set_priv(const struct nft_set *set)
628 {
629 	return (void *)set->data;
630 }
631 
632 static inline enum nft_data_types nft_set_datatype(const struct nft_set *set)
633 {
634 	return set->dtype == NFT_DATA_VERDICT ? NFT_DATA_VERDICT : NFT_DATA_VALUE;
635 }
636 
637 static inline bool nft_set_gc_is_pending(const struct nft_set *s)
638 {
639 	return refcount_read(&s->refs) != 1;
640 }
641 
642 static inline struct nft_set *nft_set_container_of(const void *priv)
643 {
644 	return (void *)priv - offsetof(struct nft_set, data);
645 }
646 
647 struct nft_set *nft_set_lookup_global(const struct net *net,
648 				      const struct nft_table *table,
649 				      const struct nlattr *nla_set_name,
650 				      const struct nlattr *nla_set_id,
651 				      u8 genmask);
652 
653 struct nft_set_ext *nft_set_catchall_lookup(const struct net *net,
654 					    const struct nft_set *set);
655 
656 static inline unsigned long nft_set_gc_interval(const struct nft_set *set)
657 {
658 	u32 gc_int = READ_ONCE(set->gc_int);
659 
660 	return gc_int ? msecs_to_jiffies(gc_int) : HZ;
661 }
662 
663 /**
664  *	struct nft_set_binding - nf_tables set binding
665  *
666  *	@list: set bindings list node
667  *	@chain: chain containing the rule bound to the set
668  *	@flags: set action flags
669  *
670  *	A set binding contains all information necessary for validation
671  *	of new elements added to a bound set.
672  */
673 struct nft_set_binding {
674 	struct list_head		list;
675 	const struct nft_chain		*chain;
676 	u32				flags;
677 };
678 
679 enum nft_trans_phase;
680 void nf_tables_activate_set(const struct nft_ctx *ctx, struct nft_set *set);
681 void nf_tables_deactivate_set(const struct nft_ctx *ctx, struct nft_set *set,
682 			      struct nft_set_binding *binding,
683 			      enum nft_trans_phase phase);
684 int nf_tables_bind_set(const struct nft_ctx *ctx, struct nft_set *set,
685 		       struct nft_set_binding *binding);
686 void nf_tables_destroy_set(const struct nft_ctx *ctx, struct nft_set *set);
687 
688 /**
689  *	enum nft_set_extensions - set extension type IDs
690  *
691  *	@NFT_SET_EXT_KEY: element key
692  *	@NFT_SET_EXT_KEY_END: upper bound element key, for ranges
693  *	@NFT_SET_EXT_DATA: mapping data
694  *	@NFT_SET_EXT_FLAGS: element flags
695  *	@NFT_SET_EXT_TIMEOUT: element timeout
696  *	@NFT_SET_EXT_USERDATA: user data associated with the element
697  *	@NFT_SET_EXT_EXPRESSIONS: expressions associated with the element
698  *	@NFT_SET_EXT_OBJREF: stateful object reference associated with element
699  *	@NFT_SET_EXT_NUM: number of extension types
700  */
701 enum nft_set_extensions {
702 	NFT_SET_EXT_KEY,
703 	NFT_SET_EXT_KEY_END,
704 	NFT_SET_EXT_DATA,
705 	NFT_SET_EXT_FLAGS,
706 	NFT_SET_EXT_TIMEOUT,
707 	NFT_SET_EXT_USERDATA,
708 	NFT_SET_EXT_EXPRESSIONS,
709 	NFT_SET_EXT_OBJREF,
710 	NFT_SET_EXT_NUM
711 };
712 
713 /**
714  *	struct nft_set_ext_type - set extension type
715  *
716  * 	@len: fixed part length of the extension
717  * 	@align: alignment requirements of the extension
718  */
719 struct nft_set_ext_type {
720 	u8	len;
721 	u8	align;
722 };
723 
724 extern const struct nft_set_ext_type nft_set_ext_types[];
725 
726 /**
727  *	struct nft_set_ext_tmpl - set extension template
728  *
729  *	@len: length of extension area
730  *	@offset: offsets of individual extension types
731  *	@ext_len: length of the expected extension(used to sanity check)
732  */
733 struct nft_set_ext_tmpl {
734 	u16	len;
735 	u8	offset[NFT_SET_EXT_NUM];
736 	u8	ext_len[NFT_SET_EXT_NUM];
737 };
738 
739 /**
740  *	struct nft_set_ext - set extensions
741  *
742  *	@genmask: generation mask, but also flags (see NFT_SET_ELEM_DEAD_BIT)
743  *	@offset: offsets of individual extension types
744  *	@data: beginning of extension data
745  *
746  *	This structure must be aligned to word size, otherwise atomic bitops
747  *	on genmask field can cause alignment failure on some archs.
748  */
749 struct nft_set_ext {
750 	u8	genmask;
751 	u8	offset[NFT_SET_EXT_NUM];
752 	char	data[];
753 } __aligned(BITS_PER_LONG / 8);
754 
755 static inline void nft_set_ext_prepare(struct nft_set_ext_tmpl *tmpl)
756 {
757 	memset(tmpl, 0, sizeof(*tmpl));
758 	tmpl->len = sizeof(struct nft_set_ext);
759 }
760 
761 static inline int nft_set_ext_add_length(struct nft_set_ext_tmpl *tmpl, u8 id,
762 					 unsigned int len)
763 {
764 	tmpl->len	 = ALIGN(tmpl->len, nft_set_ext_types[id].align);
765 	if (tmpl->len > U8_MAX)
766 		return -EINVAL;
767 
768 	tmpl->offset[id] = tmpl->len;
769 	tmpl->ext_len[id] = nft_set_ext_types[id].len + len;
770 	tmpl->len	+= tmpl->ext_len[id];
771 
772 	return 0;
773 }
774 
775 static inline int nft_set_ext_add(struct nft_set_ext_tmpl *tmpl, u8 id)
776 {
777 	return nft_set_ext_add_length(tmpl, id, 0);
778 }
779 
780 static inline void nft_set_ext_init(struct nft_set_ext *ext,
781 				    const struct nft_set_ext_tmpl *tmpl)
782 {
783 	memcpy(ext->offset, tmpl->offset, sizeof(ext->offset));
784 }
785 
786 static inline bool __nft_set_ext_exists(const struct nft_set_ext *ext, u8 id)
787 {
788 	return !!ext->offset[id];
789 }
790 
791 static inline bool nft_set_ext_exists(const struct nft_set_ext *ext, u8 id)
792 {
793 	return ext && __nft_set_ext_exists(ext, id);
794 }
795 
796 static inline void *nft_set_ext(const struct nft_set_ext *ext, u8 id)
797 {
798 	return (void *)ext + ext->offset[id];
799 }
800 
801 static inline struct nft_data *nft_set_ext_key(const struct nft_set_ext *ext)
802 {
803 	return nft_set_ext(ext, NFT_SET_EXT_KEY);
804 }
805 
806 static inline struct nft_data *nft_set_ext_key_end(const struct nft_set_ext *ext)
807 {
808 	return nft_set_ext(ext, NFT_SET_EXT_KEY_END);
809 }
810 
811 static inline struct nft_data *nft_set_ext_data(const struct nft_set_ext *ext)
812 {
813 	return nft_set_ext(ext, NFT_SET_EXT_DATA);
814 }
815 
816 static inline u8 *nft_set_ext_flags(const struct nft_set_ext *ext)
817 {
818 	return nft_set_ext(ext, NFT_SET_EXT_FLAGS);
819 }
820 
821 struct nft_timeout {
822 	u64	timeout;
823 	u64	expiration;
824 };
825 
826 static inline struct nft_timeout *nft_set_ext_timeout(const struct nft_set_ext *ext)
827 {
828 	return nft_set_ext(ext, NFT_SET_EXT_TIMEOUT);
829 }
830 
831 static inline struct nft_userdata *nft_set_ext_userdata(const struct nft_set_ext *ext)
832 {
833 	return nft_set_ext(ext, NFT_SET_EXT_USERDATA);
834 }
835 
836 static inline struct nft_set_elem_expr *nft_set_ext_expr(const struct nft_set_ext *ext)
837 {
838 	return nft_set_ext(ext, NFT_SET_EXT_EXPRESSIONS);
839 }
840 
841 static inline bool __nft_set_elem_expired(const struct nft_set_ext *ext,
842 					  u64 tstamp)
843 {
844 	if (!nft_set_ext_exists(ext, NFT_SET_EXT_TIMEOUT) ||
845 	    READ_ONCE(nft_set_ext_timeout(ext)->timeout) == 0)
846 		return false;
847 
848 	return time_after_eq64(tstamp, READ_ONCE(nft_set_ext_timeout(ext)->expiration));
849 }
850 
851 static inline bool nft_set_elem_expired(const struct nft_set_ext *ext)
852 {
853 	return __nft_set_elem_expired(ext, get_jiffies_64());
854 }
855 
856 static inline struct nft_set_ext *nft_set_elem_ext(const struct nft_set *set,
857 						   const struct nft_elem_priv *elem_priv)
858 {
859 	return (void *)elem_priv + set->ops->elemsize;
860 }
861 
862 static inline struct nft_object **nft_set_ext_obj(const struct nft_set_ext *ext)
863 {
864 	return nft_set_ext(ext, NFT_SET_EXT_OBJREF);
865 }
866 
867 struct nft_expr *nft_set_elem_expr_alloc(const struct nft_ctx *ctx,
868 					 const struct nft_set *set,
869 					 const struct nlattr *attr);
870 
871 struct nft_elem_priv *nft_set_elem_init(const struct nft_set *set,
872 					const struct nft_set_ext_tmpl *tmpl,
873 					const u32 *key, const u32 *key_end,
874 					const u32 *data,
875 					u64 timeout, u64 expiration, gfp_t gfp);
876 int nft_set_elem_expr_clone(const struct nft_ctx *ctx, struct nft_set *set,
877 			    struct nft_expr *expr_array[]);
878 void nft_set_elem_destroy(const struct nft_set *set,
879 			  const struct nft_elem_priv *elem_priv,
880 			  bool destroy_expr);
881 void nf_tables_set_elem_destroy(const struct nft_ctx *ctx,
882 				const struct nft_set *set,
883 				const struct nft_elem_priv *elem_priv);
884 
885 struct nft_expr_ops;
886 /**
887  *	struct nft_expr_type - nf_tables expression type
888  *
889  *	@select_ops: function to select nft_expr_ops
890  *	@release_ops: release nft_expr_ops
891  *	@ops: default ops, used when no select_ops functions is present
892  *	@inner_ops: inner ops, used for inner packet operation
893  *	@list: used internally
894  *	@name: Identifier
895  *	@owner: module reference
896  *	@policy: netlink attribute policy
897  *	@maxattr: highest netlink attribute number
898  *	@family: address family for AF-specific types
899  *	@flags: expression type flags
900  */
901 struct nft_expr_type {
902 	const struct nft_expr_ops	*(*select_ops)(const struct nft_ctx *,
903 						       const struct nlattr * const tb[]);
904 	void				(*release_ops)(const struct nft_expr_ops *ops);
905 	const struct nft_expr_ops	*ops;
906 	const struct nft_expr_ops	*inner_ops;
907 	struct list_head		list;
908 	const char			*name;
909 	struct module			*owner;
910 	const struct nla_policy		*policy;
911 	unsigned int			maxattr;
912 	u8				family;
913 	u8				flags;
914 };
915 
916 #define NFT_EXPR_STATEFUL		0x1
917 #define NFT_EXPR_GC			0x2
918 
919 enum nft_trans_phase {
920 	NFT_TRANS_PREPARE,
921 	NFT_TRANS_PREPARE_ERROR,
922 	NFT_TRANS_ABORT,
923 	NFT_TRANS_COMMIT,
924 	NFT_TRANS_RELEASE
925 };
926 
927 struct nft_flow_rule;
928 struct nft_offload_ctx;
929 
930 /**
931  *	struct nft_expr_ops - nf_tables expression operations
932  *
933  *	@eval: Expression evaluation function
934  *	@clone: Expression clone function
935  *	@size: full expression size, including private data size
936  *	@init: initialization function
937  *	@activate: activate expression in the next generation
938  *	@deactivate: deactivate expression in next generation
939  *	@destroy: destruction function, called after synchronize_rcu
940  *	@destroy_clone: destruction clone function
941  *	@dump: function to dump parameters
942  *	@validate: validate expression, called during loop detection
943  *	@reduce: reduce expression
944  *	@gc: garbage collection expression
945  *	@offload: hardware offload expression
946  *	@offload_action: function to report true/false to allocate one slot or not in the flow
947  *			 offload array
948  *	@offload_stats: function to synchronize hardware stats via updating the counter expression
949  *	@type: expression type
950  *	@data: extra data to attach to this expression operation
951  */
952 struct nft_expr_ops {
953 	void				(*eval)(const struct nft_expr *expr,
954 						struct nft_regs *regs,
955 						const struct nft_pktinfo *pkt);
956 	int				(*clone)(struct nft_expr *dst,
957 						 const struct nft_expr *src, gfp_t gfp);
958 	unsigned int			size;
959 
960 	int				(*init)(const struct nft_ctx *ctx,
961 						const struct nft_expr *expr,
962 						const struct nlattr * const tb[]);
963 	void				(*activate)(const struct nft_ctx *ctx,
964 						    const struct nft_expr *expr);
965 	void				(*deactivate)(const struct nft_ctx *ctx,
966 						      const struct nft_expr *expr,
967 						      enum nft_trans_phase phase);
968 	void				(*destroy)(const struct nft_ctx *ctx,
969 						   const struct nft_expr *expr);
970 	void				(*destroy_clone)(const struct nft_ctx *ctx,
971 							 const struct nft_expr *expr);
972 	int				(*dump)(struct sk_buff *skb,
973 						const struct nft_expr *expr,
974 						bool reset);
975 	int				(*validate)(const struct nft_ctx *ctx,
976 						    const struct nft_expr *expr);
977 	bool				(*reduce)(struct nft_regs_track *track,
978 						  const struct nft_expr *expr);
979 	bool				(*gc)(struct net *net,
980 					      const struct nft_expr *expr);
981 	int				(*offload)(struct nft_offload_ctx *ctx,
982 						   struct nft_flow_rule *flow,
983 						   const struct nft_expr *expr);
984 	bool				(*offload_action)(const struct nft_expr *expr);
985 	void				(*offload_stats)(struct nft_expr *expr,
986 							 const struct flow_stats *stats);
987 	const struct nft_expr_type	*type;
988 	void				*data;
989 };
990 
991 /**
992  *	struct nft_rule - nf_tables rule
993  *
994  *	@list: used internally
995  *	@handle: rule handle
996  *	@genmask: generation mask
997  *	@dlen: length of expression data
998  *	@udata: user data is appended to the rule
999  *	@data: expression data
1000  */
1001 struct nft_rule {
1002 	struct list_head		list;
1003 	u64				handle:42,
1004 					genmask:2,
1005 					dlen:12,
1006 					udata:1;
1007 	unsigned char			data[]
1008 		__attribute__((aligned(__alignof__(struct nft_expr))));
1009 };
1010 
1011 static inline struct nft_expr *nft_expr_first(const struct nft_rule *rule)
1012 {
1013 	return (struct nft_expr *)&rule->data[0];
1014 }
1015 
1016 static inline struct nft_expr *nft_expr_next(const struct nft_expr *expr)
1017 {
1018 	return ((void *)expr) + expr->ops->size;
1019 }
1020 
1021 static inline struct nft_expr *nft_expr_last(const struct nft_rule *rule)
1022 {
1023 	return (struct nft_expr *)&rule->data[rule->dlen];
1024 }
1025 
1026 static inline bool nft_expr_more(const struct nft_rule *rule,
1027 				 const struct nft_expr *expr)
1028 {
1029 	return expr != nft_expr_last(rule) && expr->ops;
1030 }
1031 
1032 static inline struct nft_userdata *nft_userdata(const struct nft_rule *rule)
1033 {
1034 	return (void *)&rule->data[rule->dlen];
1035 }
1036 
1037 void nft_rule_expr_activate(const struct nft_ctx *ctx, struct nft_rule *rule);
1038 void nft_rule_expr_deactivate(const struct nft_ctx *ctx, struct nft_rule *rule,
1039 			      enum nft_trans_phase phase);
1040 void nf_tables_rule_destroy(const struct nft_ctx *ctx, struct nft_rule *rule);
1041 
1042 static inline void nft_set_elem_update_expr(const struct nft_set_ext *ext,
1043 					    struct nft_regs *regs,
1044 					    const struct nft_pktinfo *pkt)
1045 {
1046 	struct nft_set_elem_expr *elem_expr;
1047 	struct nft_expr *expr;
1048 	u32 size;
1049 
1050 	if (__nft_set_ext_exists(ext, NFT_SET_EXT_EXPRESSIONS)) {
1051 		elem_expr = nft_set_ext_expr(ext);
1052 		nft_setelem_expr_foreach(expr, elem_expr, size) {
1053 			expr->ops->eval(expr, regs, pkt);
1054 			if (regs->verdict.code == NFT_BREAK)
1055 				return;
1056 		}
1057 	}
1058 }
1059 
1060 /*
1061  * The last pointer isn't really necessary, but the compiler isn't able to
1062  * determine that the result of nft_expr_last() is always the same since it
1063  * can't assume that the dlen value wasn't changed within calls in the loop.
1064  */
1065 #define nft_rule_for_each_expr(expr, last, rule) \
1066 	for ((expr) = nft_expr_first(rule), (last) = nft_expr_last(rule); \
1067 	     (expr) != (last); \
1068 	     (expr) = nft_expr_next(expr))
1069 
1070 #define NFT_CHAIN_POLICY_UNSET		U8_MAX
1071 
1072 struct nft_rule_dp {
1073 	u64				is_last:1,
1074 					dlen:12,
1075 					handle:42;	/* for tracing */
1076 	unsigned char			data[]
1077 		__attribute__((aligned(__alignof__(struct nft_expr))));
1078 };
1079 
1080 struct nft_rule_dp_last {
1081 	struct nft_rule_dp end;		/* end of nft_rule_blob marker */
1082 	struct rcu_head h;		/* call_rcu head */
1083 	struct nft_rule_blob *blob;	/* ptr to free via call_rcu */
1084 	const struct nft_chain *chain;	/* for nftables tracing */
1085 };
1086 
1087 static inline const struct nft_rule_dp *nft_rule_next(const struct nft_rule_dp *rule)
1088 {
1089 	return (void *)rule + sizeof(*rule) + rule->dlen;
1090 }
1091 
1092 struct nft_rule_blob {
1093 	unsigned long			size;
1094 	unsigned char			data[]
1095 		__attribute__((aligned(__alignof__(struct nft_rule_dp))));
1096 };
1097 
1098 /**
1099  *	struct nft_chain - nf_tables chain
1100  *
1101  *	@blob_gen_0: rule blob pointer to the current generation
1102  *	@blob_gen_1: rule blob pointer to the future generation
1103  *	@rules: list of rules in the chain
1104  *	@list: used internally
1105  *	@rhlhead: used internally
1106  *	@table: table that this chain belongs to
1107  *	@handle: chain handle
1108  *	@use: number of jump references to this chain
1109  *	@flags: bitmask of enum NFTA_CHAIN_FLAGS
1110  *	@bound: bind or not
1111  *	@genmask: generation mask
1112  *	@name: name of the chain
1113  *	@udlen: user data length
1114  *	@udata: user data in the chain
1115  *	@blob_next: rule blob pointer to the next in the chain
1116  */
1117 struct nft_chain {
1118 	struct nft_rule_blob		__rcu *blob_gen_0;
1119 	struct nft_rule_blob		__rcu *blob_gen_1;
1120 	struct list_head		rules;
1121 	struct list_head		list;
1122 	struct rhlist_head		rhlhead;
1123 	struct nft_table		*table;
1124 	u64				handle;
1125 	u32				use;
1126 	u8				flags:5,
1127 					bound:1,
1128 					genmask:2;
1129 	char				*name;
1130 	u16				udlen;
1131 	u8				*udata;
1132 
1133 	/* Only used during control plane commit phase: */
1134 	struct nft_rule_blob		*blob_next;
1135 };
1136 
1137 int nft_chain_validate(const struct nft_ctx *ctx, const struct nft_chain *chain);
1138 int nft_setelem_validate(const struct nft_ctx *ctx, struct nft_set *set,
1139 			 const struct nft_set_iter *iter,
1140 			 struct nft_elem_priv *elem_priv);
1141 int nft_set_catchall_validate(const struct nft_ctx *ctx, struct nft_set *set);
1142 int nf_tables_bind_chain(const struct nft_ctx *ctx, struct nft_chain *chain);
1143 void nf_tables_unbind_chain(const struct nft_ctx *ctx, struct nft_chain *chain);
1144 
1145 struct nft_hook;
1146 void nf_tables_chain_device_notify(const struct nft_chain *chain,
1147 				   const struct nft_hook *hook,
1148 				   const struct net_device *dev, int event);
1149 
1150 enum nft_chain_types {
1151 	NFT_CHAIN_T_DEFAULT = 0,
1152 	NFT_CHAIN_T_ROUTE,
1153 	NFT_CHAIN_T_NAT,
1154 	NFT_CHAIN_T_MAX
1155 };
1156 
1157 /**
1158  * 	struct nft_chain_type - nf_tables chain type info
1159  *
1160  * 	@name: name of the type
1161  * 	@type: numeric identifier
1162  * 	@family: address family
1163  * 	@owner: module owner
1164  * 	@hook_mask: mask of valid hooks
1165  * 	@hooks: array of hook functions
1166  *	@ops_register: base chain register function
1167  *	@ops_unregister: base chain unregister function
1168  */
1169 struct nft_chain_type {
1170 	const char			*name;
1171 	enum nft_chain_types		type;
1172 	int				family;
1173 	struct module			*owner;
1174 	unsigned int			hook_mask;
1175 	nf_hookfn			*hooks[NFT_MAX_HOOKS];
1176 	int				(*ops_register)(struct net *net, const struct nf_hook_ops *ops);
1177 	void				(*ops_unregister)(struct net *net, const struct nf_hook_ops *ops);
1178 };
1179 
1180 int nft_chain_validate_dependency(const struct nft_chain *chain,
1181 				  enum nft_chain_types type);
1182 int nft_chain_validate_hooks(const struct nft_chain *chain,
1183                              unsigned int hook_flags);
1184 
1185 static inline bool nft_chain_binding(const struct nft_chain *chain)
1186 {
1187 	return chain->flags & NFT_CHAIN_BINDING;
1188 }
1189 
1190 static inline bool nft_chain_is_bound(struct nft_chain *chain)
1191 {
1192 	return (chain->flags & NFT_CHAIN_BINDING) && chain->bound;
1193 }
1194 
1195 int nft_chain_add(struct nft_table *table, struct nft_chain *chain);
1196 void nft_chain_del(struct nft_chain *chain);
1197 void nf_tables_chain_destroy(struct nft_chain *chain);
1198 
1199 struct nft_stats {
1200 	u64			bytes;
1201 	u64			pkts;
1202 	struct u64_stats_sync	syncp;
1203 };
1204 
1205 struct nft_hook {
1206 	struct list_head	list;
1207 	struct list_head	ops_list;
1208 	struct rcu_head		rcu;
1209 	char			ifname[IFNAMSIZ];
1210 	u8			ifnamelen;
1211 };
1212 
1213 struct nf_hook_ops *nft_hook_find_ops(const struct nft_hook *hook,
1214 				      const struct net_device *dev);
1215 struct nf_hook_ops *nft_hook_find_ops_rcu(const struct nft_hook *hook,
1216 					  const struct net_device *dev);
1217 
1218 /**
1219  *	struct nft_base_chain - nf_tables base chain
1220  *
1221  *	@ops: netfilter hook ops
1222  *	@hook_list: list of netfilter hooks (for NFPROTO_NETDEV family)
1223  *	@type: chain type
1224  *	@policy: default policy
1225  *	@flags: indicate the base chain disabled or not
1226  *	@stats: per-cpu chain stats
1227  *	@chain: the chain
1228  *	@flow_block: flow block (for hardware offload)
1229  */
1230 struct nft_base_chain {
1231 	struct nf_hook_ops		ops;
1232 	struct list_head		hook_list;
1233 	const struct nft_chain_type	*type;
1234 	u8				policy;
1235 	u8				flags;
1236 	struct nft_stats __percpu	*stats;
1237 	struct nft_chain		chain;
1238 	struct flow_block		flow_block;
1239 };
1240 
1241 static inline struct nft_base_chain *nft_base_chain(const struct nft_chain *chain)
1242 {
1243 	return container_of(chain, struct nft_base_chain, chain);
1244 }
1245 
1246 static inline bool nft_is_base_chain(const struct nft_chain *chain)
1247 {
1248 	return chain->flags & NFT_CHAIN_BASE;
1249 }
1250 
1251 unsigned int nft_do_chain(struct nft_pktinfo *pkt, void *priv);
1252 
1253 static inline bool nft_use_inc(u32 *use)
1254 {
1255 	if (*use == UINT_MAX)
1256 		return false;
1257 
1258 	(*use)++;
1259 
1260 	return true;
1261 }
1262 
1263 static inline void nft_use_dec(u32 *use)
1264 {
1265 	WARN_ON_ONCE((*use)-- == 0);
1266 }
1267 
1268 /* For error and abort path: restore use counter to previous state. */
1269 static inline void nft_use_inc_restore(u32 *use)
1270 {
1271 	WARN_ON_ONCE(!nft_use_inc(use));
1272 }
1273 
1274 #define nft_use_dec_restore	nft_use_dec
1275 
1276 /**
1277  *	struct nft_table - nf_tables table
1278  *
1279  *	@list: used internally
1280  *	@chains_ht: chains in the table
1281  *	@chains: same, for stable walks
1282  *	@sets: sets in the table
1283  *	@objects: stateful objects in the table
1284  *	@flowtables: flow tables in the table
1285  *	@hgenerator: handle generator state
1286  *	@handle: table handle
1287  *	@use: number of chain references to this table
1288  *	@family:address family
1289  *	@flags: table flag (see enum nft_table_flags)
1290  *	@genmask: generation mask
1291  *	@nlpid: netlink port ID
1292  *	@name: name of the table
1293  *	@udlen: length of the user data
1294  *	@udata: user data
1295  *	@validate_state: internal, set when transaction adds jumps
1296  */
1297 struct nft_table {
1298 	struct list_head		list;
1299 	struct rhltable			chains_ht;
1300 	struct list_head		chains;
1301 	struct list_head		sets;
1302 	struct list_head		objects;
1303 	struct list_head		flowtables;
1304 	u64				hgenerator;
1305 	u64				handle;
1306 	u32				use;
1307 	u16				family:6,
1308 					flags:8,
1309 					genmask:2;
1310 	u32				nlpid;
1311 	char				*name;
1312 	u16				udlen;
1313 	u8				*udata;
1314 	u8				validate_state;
1315 };
1316 
1317 static inline bool nft_table_has_owner(const struct nft_table *table)
1318 {
1319 	return table->flags & NFT_TABLE_F_OWNER;
1320 }
1321 
1322 static inline bool nft_table_is_orphan(const struct nft_table *table)
1323 {
1324 	return (table->flags & (NFT_TABLE_F_OWNER | NFT_TABLE_F_PERSIST)) ==
1325 			NFT_TABLE_F_PERSIST;
1326 }
1327 
1328 static inline bool nft_base_chain_netdev(int family, u32 hooknum)
1329 {
1330 	return family == NFPROTO_NETDEV ||
1331 	       (family == NFPROTO_INET && hooknum == NF_INET_INGRESS);
1332 }
1333 
1334 void nft_register_chain_type(const struct nft_chain_type *);
1335 void nft_unregister_chain_type(const struct nft_chain_type *);
1336 
1337 int nft_register_expr(struct nft_expr_type *);
1338 void nft_unregister_expr(struct nft_expr_type *);
1339 
1340 int nft_verdict_dump(struct sk_buff *skb, int type,
1341 		     const struct nft_verdict *v);
1342 
1343 /**
1344  *	struct nft_object_hash_key - key to lookup nft_object
1345  *
1346  *	@name: name of the stateful object to look up
1347  *	@table: table the object belongs to
1348  */
1349 struct nft_object_hash_key {
1350 	const char                      *name;
1351 	const struct nft_table          *table;
1352 };
1353 
1354 /**
1355  *	struct nft_object - nf_tables stateful object
1356  *
1357  *	@list: table stateful object list node
1358  *	@rhlhead: nft_objname_ht node
1359  *	@key: keys that identify this object
1360  *	@genmask: generation mask
1361  *	@use: number of references to this stateful object
1362  *	@handle: unique object handle
1363  *	@udlen: length of user data
1364  *	@udata: user data
1365  *	@ops: object operations
1366  *	@data: object data, layout depends on type
1367  */
1368 struct nft_object {
1369 	struct list_head		list;
1370 	struct rhlist_head		rhlhead;
1371 	struct nft_object_hash_key	key;
1372 	u32				genmask:2;
1373 	u32				use;
1374 	u64				handle;
1375 	u16				udlen;
1376 	u8				*udata;
1377 	/* runtime data below here */
1378 	const struct nft_object_ops	*ops ____cacheline_aligned;
1379 	unsigned char			data[]
1380 		__attribute__((aligned(__alignof__(u64))));
1381 };
1382 
1383 static inline void *nft_obj_data(const struct nft_object *obj)
1384 {
1385 	return (void *)obj->data;
1386 }
1387 
1388 #define nft_expr_obj(expr)	*((struct nft_object **)nft_expr_priv(expr))
1389 
1390 struct nft_object *nft_obj_lookup(const struct net *net,
1391 				  const struct nft_table *table,
1392 				  const struct nlattr *nla, u32 objtype,
1393 				  u8 genmask);
1394 
1395 void nft_obj_notify(struct net *net, const struct nft_table *table,
1396 		    struct nft_object *obj, u32 portid, u32 seq,
1397 		    int event, u16 flags, int family, int report, gfp_t gfp);
1398 
1399 /**
1400  *	struct nft_object_type - stateful object type
1401  *
1402  *	@select_ops: function to select nft_object_ops
1403  *	@ops: default ops, used when no select_ops functions is present
1404  *	@list: list node in list of object types
1405  *	@type: stateful object numeric type
1406  *	@owner: module owner
1407  *	@maxattr: maximum netlink attribute
1408  *	@family: address family for AF-specific object types
1409  *	@policy: netlink attribute policy
1410  */
1411 struct nft_object_type {
1412 	const struct nft_object_ops	*(*select_ops)(const struct nft_ctx *,
1413 						       const struct nlattr * const tb[]);
1414 	const struct nft_object_ops	*ops;
1415 	struct list_head		list;
1416 	u32				type;
1417 	unsigned int                    maxattr;
1418 	u8				family;
1419 	struct module			*owner;
1420 	const struct nla_policy		*policy;
1421 };
1422 
1423 /**
1424  *	struct nft_object_ops - stateful object operations
1425  *
1426  *	@eval: stateful object evaluation function
1427  *	@size: stateful object size
1428  *	@init: initialize object from netlink attributes
1429  *	@destroy: release existing stateful object
1430  *	@dump: netlink dump stateful object
1431  *	@update: update stateful object
1432  *	@type: pointer to object type
1433  */
1434 struct nft_object_ops {
1435 	void				(*eval)(struct nft_object *obj,
1436 						struct nft_regs *regs,
1437 						const struct nft_pktinfo *pkt);
1438 	unsigned int			size;
1439 	int				(*init)(const struct nft_ctx *ctx,
1440 						const struct nlattr *const tb[],
1441 						struct nft_object *obj);
1442 	void				(*destroy)(const struct nft_ctx *ctx,
1443 						   struct nft_object *obj);
1444 	int				(*dump)(struct sk_buff *skb,
1445 						struct nft_object *obj,
1446 						bool reset);
1447 	void				(*update)(struct nft_object *obj,
1448 						  struct nft_object *newobj);
1449 	const struct nft_object_type	*type;
1450 };
1451 
1452 int nft_register_obj(struct nft_object_type *obj_type);
1453 void nft_unregister_obj(struct nft_object_type *obj_type);
1454 
1455 #define NFT_NETDEVICE_MAX	256
1456 
1457 /**
1458  *	struct nft_flowtable - nf_tables flow table
1459  *
1460  *	@list: flow table list node in table list
1461  * 	@table: the table the flow table is contained in
1462  *	@name: name of this flow table
1463  *	@hooknum: hook number
1464  *	@ops_len: number of hooks in array
1465  *	@genmask: generation mask
1466  *	@use: number of references to this flow table
1467  * 	@handle: unique object handle
1468  *	@hook_list: hook list for hooks per net_device in flowtables
1469  *	@data: rhashtable and garbage collector
1470  */
1471 struct nft_flowtable {
1472 	struct list_head		list;
1473 	struct nft_table		*table;
1474 	char				*name;
1475 	int				hooknum;
1476 	int				ops_len;
1477 	u32				genmask:2;
1478 	u32				use;
1479 	u64				handle;
1480 	/* runtime data below here */
1481 	struct list_head		hook_list ____cacheline_aligned;
1482 	struct nf_flowtable		data;
1483 };
1484 
1485 struct nft_flowtable *nft_flowtable_lookup(const struct net *net,
1486 					   const struct nft_table *table,
1487 					   const struct nlattr *nla,
1488 					   u8 genmask);
1489 
1490 void nf_tables_deactivate_flowtable(const struct nft_ctx *ctx,
1491 				    struct nft_flowtable *flowtable,
1492 				    enum nft_trans_phase phase);
1493 
1494 void nft_register_flowtable_type(struct nf_flowtable_type *type);
1495 void nft_unregister_flowtable_type(struct nf_flowtable_type *type);
1496 
1497 /**
1498  *	struct nft_traceinfo - nft tracing information and state
1499  *
1500  *	@trace: other struct members are initialised
1501  *	@nf_trace: copy of skb->nf_trace before rule evaluation
1502  *	@type: event type (enum nft_trace_types)
1503  *	@skbid: hash of skb to be used as trace id
1504  *	@packet_dumped: packet headers sent in a previous traceinfo message
1505  *	@basechain: base chain currently processed
1506  */
1507 struct nft_traceinfo {
1508 	bool				trace;
1509 	bool				nf_trace;
1510 	bool				packet_dumped;
1511 	enum nft_trace_types		type:8;
1512 	u32				skbid;
1513 	const struct nft_base_chain	*basechain;
1514 };
1515 
1516 void nft_trace_init(struct nft_traceinfo *info, const struct nft_pktinfo *pkt,
1517 		    const struct nft_chain *basechain);
1518 
1519 void nft_trace_notify(const struct nft_pktinfo *pkt,
1520 		      const struct nft_verdict *verdict,
1521 		      const struct nft_rule_dp *rule,
1522 		      struct nft_traceinfo *info);
1523 
1524 #define MODULE_ALIAS_NFT_CHAIN(family, name) \
1525 	MODULE_ALIAS("nft-chain-" __stringify(family) "-" name)
1526 
1527 #define MODULE_ALIAS_NFT_AF_EXPR(family, name) \
1528 	MODULE_ALIAS("nft-expr-" __stringify(family) "-" name)
1529 
1530 #define MODULE_ALIAS_NFT_EXPR(name) \
1531 	MODULE_ALIAS("nft-expr-" name)
1532 
1533 #define MODULE_ALIAS_NFT_OBJ(type) \
1534 	MODULE_ALIAS("nft-obj-" __stringify(type))
1535 
1536 #if IS_ENABLED(CONFIG_NF_TABLES)
1537 
1538 /*
1539  * The gencursor defines two generations, the currently active and the
1540  * next one. Objects contain a bitmask of 2 bits specifying the generations
1541  * they're active in. A set bit means they're inactive in the generation
1542  * represented by that bit.
1543  *
1544  * New objects start out as inactive in the current and active in the
1545  * next generation. When committing the ruleset the bitmask is cleared,
1546  * meaning they're active in all generations. When removing an object,
1547  * it is set inactive in the next generation. After committing the ruleset,
1548  * the objects are removed.
1549  */
1550 static inline unsigned int nft_gencursor_next(const struct net *net)
1551 {
1552 	return net->nft.gencursor + 1 == 1 ? 1 : 0;
1553 }
1554 
1555 static inline u8 nft_genmask_next(const struct net *net)
1556 {
1557 	return 1 << nft_gencursor_next(net);
1558 }
1559 
1560 static inline u8 nft_genmask_cur(const struct net *net)
1561 {
1562 	/* Use READ_ONCE() to prevent refetching the value for atomicity */
1563 	return 1 << READ_ONCE(net->nft.gencursor);
1564 }
1565 
1566 #define NFT_GENMASK_ANY		((1 << 0) | (1 << 1))
1567 
1568 /*
1569  * Generic transaction helpers
1570  */
1571 
1572 /* Check if this object is currently active. */
1573 #define nft_is_active(__net, __obj)				\
1574 	(((__obj)->genmask & nft_genmask_cur(__net)) == 0)
1575 
1576 /* Check if this object is active in the next generation. */
1577 #define nft_is_active_next(__net, __obj)			\
1578 	(((__obj)->genmask & nft_genmask_next(__net)) == 0)
1579 
1580 /* This object becomes active in the next generation. */
1581 #define nft_activate_next(__net, __obj)				\
1582 	(__obj)->genmask = nft_genmask_cur(__net)
1583 
1584 /* This object becomes inactive in the next generation. */
1585 #define nft_deactivate_next(__net, __obj)			\
1586         (__obj)->genmask = nft_genmask_next(__net)
1587 
1588 /* After committing the ruleset, clear the stale generation bit. */
1589 #define nft_clear(__net, __obj)					\
1590 	(__obj)->genmask &= ~nft_genmask_next(__net)
1591 #define nft_active_genmask(__obj, __genmask)			\
1592 	!((__obj)->genmask & __genmask)
1593 
1594 /*
1595  * Set element transaction helpers
1596  */
1597 
1598 static inline bool nft_set_elem_active(const struct nft_set_ext *ext,
1599 				       u8 genmask)
1600 {
1601 	return !(ext->genmask & genmask);
1602 }
1603 
1604 static inline void nft_set_elem_change_active(const struct net *net,
1605 					      const struct nft_set *set,
1606 					      struct nft_set_ext *ext)
1607 {
1608 	ext->genmask ^= nft_genmask_next(net);
1609 }
1610 
1611 #endif /* IS_ENABLED(CONFIG_NF_TABLES) */
1612 
1613 #define NFT_SET_ELEM_DEAD_MASK	(1 << 2)
1614 
1615 #if defined(__LITTLE_ENDIAN_BITFIELD)
1616 #define NFT_SET_ELEM_DEAD_BIT	2
1617 #elif defined(__BIG_ENDIAN_BITFIELD)
1618 #define NFT_SET_ELEM_DEAD_BIT	(BITS_PER_LONG - BITS_PER_BYTE + 2)
1619 #else
1620 #error
1621 #endif
1622 
1623 static inline void nft_set_elem_dead(struct nft_set_ext *ext)
1624 {
1625 	unsigned long *word = (unsigned long *)ext;
1626 
1627 	BUILD_BUG_ON(offsetof(struct nft_set_ext, genmask) != 0);
1628 	set_bit(NFT_SET_ELEM_DEAD_BIT, word);
1629 }
1630 
1631 static inline int nft_set_elem_is_dead(const struct nft_set_ext *ext)
1632 {
1633 	unsigned long *word = (unsigned long *)ext;
1634 
1635 	BUILD_BUG_ON(offsetof(struct nft_set_ext, genmask) != 0);
1636 	return test_bit(NFT_SET_ELEM_DEAD_BIT, word);
1637 }
1638 
1639 /**
1640  * struct nft_trans - nf_tables object update in transaction
1641  *
1642  * @list: used internally
1643  * @net: struct net
1644  * @table: struct nft_table the object resides in
1645  * @msg_type: message type
1646  * @seq: netlink sequence number
1647  * @flags: modifiers to new request
1648  * @report: notify via unicast netlink message
1649  * @put_net: net needs to be put
1650  *
1651  * This is the information common to all objects in the transaction,
1652  * this must always be the first member of derived sub-types.
1653  */
1654 struct nft_trans {
1655 	struct list_head		list;
1656 	struct net			*net;
1657 	struct nft_table		*table;
1658 	int				msg_type;
1659 	u32				seq;
1660 	u16				flags;
1661 	u8				report:1;
1662 	u8				put_net:1;
1663 };
1664 
1665 /**
1666  * struct nft_trans_binding - nf_tables object with binding support in transaction
1667  * @nft_trans:    base structure, MUST be first member
1668  * @binding_list: list of objects with possible bindings
1669  *
1670  * This is the base type used by objects that can be bound to a chain.
1671  */
1672 struct nft_trans_binding {
1673 	struct nft_trans nft_trans;
1674 	struct list_head binding_list;
1675 };
1676 
1677 struct nft_trans_rule {
1678 	struct nft_trans		nft_trans;
1679 	struct nft_rule			*rule;
1680 	struct nft_chain		*chain;
1681 	struct nft_flow_rule		*flow;
1682 	u32				rule_id;
1683 	bool				bound;
1684 };
1685 
1686 #define nft_trans_container_rule(trans)			\
1687 	container_of(trans, struct nft_trans_rule, nft_trans)
1688 #define nft_trans_rule(trans)				\
1689 	nft_trans_container_rule(trans)->rule
1690 #define nft_trans_flow_rule(trans)			\
1691 	nft_trans_container_rule(trans)->flow
1692 #define nft_trans_rule_id(trans)			\
1693 	nft_trans_container_rule(trans)->rule_id
1694 #define nft_trans_rule_bound(trans)			\
1695 	nft_trans_container_rule(trans)->bound
1696 #define nft_trans_rule_chain(trans)	\
1697 	nft_trans_container_rule(trans)->chain
1698 
1699 struct nft_trans_set {
1700 	struct nft_trans_binding	nft_trans_binding;
1701 	struct list_head		list_trans_newset;
1702 	struct nft_set			*set;
1703 	u32				set_id;
1704 	u32				gc_int;
1705 	u64				timeout;
1706 	bool				update;
1707 	bool				bound;
1708 	u32				size;
1709 };
1710 
1711 #define nft_trans_container_set(t)	\
1712 	container_of(t, struct nft_trans_set, nft_trans_binding.nft_trans)
1713 #define nft_trans_set(trans)				\
1714 	nft_trans_container_set(trans)->set
1715 #define nft_trans_set_id(trans)				\
1716 	nft_trans_container_set(trans)->set_id
1717 #define nft_trans_set_bound(trans)			\
1718 	nft_trans_container_set(trans)->bound
1719 #define nft_trans_set_update(trans)			\
1720 	nft_trans_container_set(trans)->update
1721 #define nft_trans_set_timeout(trans)			\
1722 	nft_trans_container_set(trans)->timeout
1723 #define nft_trans_set_gc_int(trans)			\
1724 	nft_trans_container_set(trans)->gc_int
1725 #define nft_trans_set_size(trans)			\
1726 	nft_trans_container_set(trans)->size
1727 
1728 struct nft_trans_chain {
1729 	struct nft_trans_binding	nft_trans_binding;
1730 	struct nft_chain		*chain;
1731 	char				*name;
1732 	struct nft_stats __percpu	*stats;
1733 	u8				policy;
1734 	bool				update;
1735 	bool				bound;
1736 	u32				chain_id;
1737 	struct nft_base_chain		*basechain;
1738 	struct list_head		hook_list;
1739 };
1740 
1741 #define nft_trans_container_chain(t)	\
1742 	container_of(t, struct nft_trans_chain, nft_trans_binding.nft_trans)
1743 #define nft_trans_chain(trans)				\
1744 	nft_trans_container_chain(trans)->chain
1745 #define nft_trans_chain_update(trans)			\
1746 	nft_trans_container_chain(trans)->update
1747 #define nft_trans_chain_name(trans)			\
1748 	nft_trans_container_chain(trans)->name
1749 #define nft_trans_chain_stats(trans)			\
1750 	nft_trans_container_chain(trans)->stats
1751 #define nft_trans_chain_policy(trans)			\
1752 	nft_trans_container_chain(trans)->policy
1753 #define nft_trans_chain_bound(trans)			\
1754 	nft_trans_container_chain(trans)->bound
1755 #define nft_trans_chain_id(trans)			\
1756 	nft_trans_container_chain(trans)->chain_id
1757 #define nft_trans_basechain(trans)			\
1758 	nft_trans_container_chain(trans)->basechain
1759 #define nft_trans_chain_hooks(trans)			\
1760 	nft_trans_container_chain(trans)->hook_list
1761 
1762 struct nft_trans_table {
1763 	struct nft_trans		nft_trans;
1764 	bool				update;
1765 };
1766 
1767 #define nft_trans_container_table(trans)		\
1768 	container_of(trans, struct nft_trans_table, nft_trans)
1769 #define nft_trans_table_update(trans)			\
1770 	nft_trans_container_table(trans)->update
1771 
1772 enum nft_trans_elem_flags {
1773 	NFT_TRANS_UPD_TIMEOUT		= (1 << 0),
1774 	NFT_TRANS_UPD_EXPIRATION	= (1 << 1),
1775 };
1776 
1777 struct nft_elem_update {
1778 	u64				timeout;
1779 	u64				expiration;
1780 	u8				flags;
1781 };
1782 
1783 struct nft_trans_one_elem {
1784 	struct nft_elem_priv		*priv;
1785 	struct nft_elem_update		*update;
1786 };
1787 
1788 struct nft_trans_elem {
1789 	struct nft_trans		nft_trans;
1790 	struct nft_set			*set;
1791 	bool				bound;
1792 	unsigned int			nelems;
1793 	struct nft_trans_one_elem	elems[] __counted_by(nelems);
1794 };
1795 
1796 #define nft_trans_container_elem(t)			\
1797 	container_of(t, struct nft_trans_elem, nft_trans)
1798 #define nft_trans_elem_set(trans)			\
1799 	nft_trans_container_elem(trans)->set
1800 #define nft_trans_elem_set_bound(trans)			\
1801 	nft_trans_container_elem(trans)->bound
1802 
1803 struct nft_trans_obj {
1804 	struct nft_trans		nft_trans;
1805 	struct nft_object		*obj;
1806 	struct nft_object		*newobj;
1807 	bool				update;
1808 };
1809 
1810 #define nft_trans_container_obj(t)			\
1811 	container_of(t, struct nft_trans_obj, nft_trans)
1812 #define nft_trans_obj(trans)				\
1813 	nft_trans_container_obj(trans)->obj
1814 #define nft_trans_obj_newobj(trans)			\
1815 	nft_trans_container_obj(trans)->newobj
1816 #define nft_trans_obj_update(trans)			\
1817 	nft_trans_container_obj(trans)->update
1818 
1819 struct nft_trans_flowtable {
1820 	struct nft_trans		nft_trans;
1821 	struct nft_flowtable		*flowtable;
1822 	struct list_head		hook_list;
1823 	u32				flags;
1824 	bool				update;
1825 };
1826 
1827 #define nft_trans_container_flowtable(t)		\
1828 	container_of(t, struct nft_trans_flowtable, nft_trans)
1829 #define nft_trans_flowtable(trans)			\
1830 	nft_trans_container_flowtable(trans)->flowtable
1831 #define nft_trans_flowtable_update(trans)		\
1832 	nft_trans_container_flowtable(trans)->update
1833 #define nft_trans_flowtable_hooks(trans)		\
1834 	nft_trans_container_flowtable(trans)->hook_list
1835 #define nft_trans_flowtable_flags(trans)		\
1836 	nft_trans_container_flowtable(trans)->flags
1837 
1838 #define NFT_TRANS_GC_BATCHCOUNT	256
1839 
1840 struct nft_trans_gc {
1841 	struct list_head	list;
1842 	struct net		*net;
1843 	struct nft_set		*set;
1844 	u32			seq;
1845 	u16			count;
1846 	struct nft_elem_priv	*priv[NFT_TRANS_GC_BATCHCOUNT];
1847 	struct rcu_head		rcu;
1848 };
1849 
1850 static inline void nft_ctx_update(struct nft_ctx *ctx,
1851 				  const struct nft_trans *trans)
1852 {
1853 	switch (trans->msg_type) {
1854 	case NFT_MSG_NEWRULE:
1855 	case NFT_MSG_DELRULE:
1856 	case NFT_MSG_DESTROYRULE:
1857 		ctx->chain = nft_trans_rule_chain(trans);
1858 		break;
1859 	case NFT_MSG_NEWCHAIN:
1860 	case NFT_MSG_DELCHAIN:
1861 	case NFT_MSG_DESTROYCHAIN:
1862 		ctx->chain = nft_trans_chain(trans);
1863 		break;
1864 	default:
1865 		ctx->chain = NULL;
1866 		break;
1867 	}
1868 
1869 	ctx->net = trans->net;
1870 	ctx->table = trans->table;
1871 	ctx->family = trans->table->family;
1872 	ctx->report = trans->report;
1873 	ctx->flags = trans->flags;
1874 	ctx->seq = trans->seq;
1875 }
1876 
1877 struct nft_trans_gc *nft_trans_gc_alloc(struct nft_set *set,
1878 					unsigned int gc_seq, gfp_t gfp);
1879 void nft_trans_gc_destroy(struct nft_trans_gc *trans);
1880 
1881 struct nft_trans_gc *nft_trans_gc_queue_async(struct nft_trans_gc *gc,
1882 					      unsigned int gc_seq, gfp_t gfp);
1883 void nft_trans_gc_queue_async_done(struct nft_trans_gc *gc);
1884 
1885 struct nft_trans_gc *nft_trans_gc_queue_sync(struct nft_trans_gc *gc, gfp_t gfp);
1886 void nft_trans_gc_queue_sync_done(struct nft_trans_gc *trans);
1887 
1888 void nft_trans_gc_elem_add(struct nft_trans_gc *gc, void *priv);
1889 
1890 struct nft_trans_gc *nft_trans_gc_catchall_async(struct nft_trans_gc *gc,
1891 						 unsigned int gc_seq);
1892 struct nft_trans_gc *nft_trans_gc_catchall_sync(struct nft_trans_gc *gc);
1893 
1894 void nft_setelem_data_deactivate(const struct net *net,
1895 				 const struct nft_set *set,
1896 				 struct nft_elem_priv *elem_priv);
1897 
1898 int __init nft_chain_filter_init(void);
1899 void nft_chain_filter_fini(void);
1900 
1901 void __init nft_chain_route_init(void);
1902 void nft_chain_route_fini(void);
1903 
1904 void nf_tables_trans_destroy_flush_work(struct net *net);
1905 
1906 int nf_msecs_to_jiffies64(const struct nlattr *nla, u64 *result);
1907 __be64 nf_jiffies64_to_msecs(u64 input);
1908 
1909 #ifdef CONFIG_MODULES
1910 __printf(2, 3) int nft_request_module(struct net *net, const char *fmt, ...);
1911 #else
1912 static inline int nft_request_module(struct net *net, const char *fmt, ...) { return -ENOENT; }
1913 #endif
1914 
1915 struct nftables_pernet {
1916 	struct list_head	tables;
1917 	struct list_head	commit_list;
1918 	struct list_head	destroy_list;
1919 	struct list_head	commit_set_list;
1920 	struct list_head	binding_list;
1921 	struct list_head	module_list;
1922 	struct list_head	notify_list;
1923 	struct mutex		commit_mutex;
1924 	u64			table_handle;
1925 	u64			tstamp;
1926 	unsigned int		base_seq;
1927 	unsigned int		gc_seq;
1928 	u8			validate_state;
1929 	struct work_struct	destroy_work;
1930 };
1931 
1932 extern unsigned int nf_tables_net_id;
1933 
1934 static inline struct nftables_pernet *nft_pernet(const struct net *net)
1935 {
1936 	return net_generic(net, nf_tables_net_id);
1937 }
1938 
1939 static inline u64 nft_net_tstamp(const struct net *net)
1940 {
1941 	return nft_pernet(net)->tstamp;
1942 }
1943 
1944 #define __NFT_REDUCE_READONLY	1UL
1945 #define NFT_REDUCE_READONLY	(void *)__NFT_REDUCE_READONLY
1946 
1947 static inline bool nft_reduce_is_readonly(const struct nft_expr *expr)
1948 {
1949 	return expr->ops->reduce == NFT_REDUCE_READONLY;
1950 }
1951 
1952 void nft_reg_track_update(struct nft_regs_track *track,
1953 			  const struct nft_expr *expr, u8 dreg, u8 len);
1954 void nft_reg_track_cancel(struct nft_regs_track *track, u8 dreg, u8 len);
1955 void __nft_reg_track_cancel(struct nft_regs_track *track, u8 dreg);
1956 
1957 static inline bool nft_reg_track_cmp(struct nft_regs_track *track,
1958 				     const struct nft_expr *expr, u8 dreg)
1959 {
1960 	return track->regs[dreg].selector &&
1961 	       track->regs[dreg].selector->ops == expr->ops &&
1962 	       track->regs[dreg].num_reg == 0;
1963 }
1964 
1965 #endif /* _NET_NF_TABLES_H */
1966