1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _NET_NF_TABLES_H
3 #define _NET_NF_TABLES_H
4 
5 #include <asm/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 struct nft_pktinfo {
25 	struct sk_buff			*skb;
26 	const struct nf_hook_state	*state;
27 	bool				tprot_set;
28 	u8				tprot;
29 	u16				fragoff;
30 	unsigned int			thoff;
31 };
32 
33 static inline struct sock *nft_sk(const struct nft_pktinfo *pkt)
34 {
35 	return pkt->state->sk;
36 }
37 
38 static inline unsigned int nft_thoff(const struct nft_pktinfo *pkt)
39 {
40 	return pkt->thoff;
41 }
42 
43 static inline struct net *nft_net(const struct nft_pktinfo *pkt)
44 {
45 	return pkt->state->net;
46 }
47 
48 static inline unsigned int nft_hook(const struct nft_pktinfo *pkt)
49 {
50 	return pkt->state->hook;
51 }
52 
53 static inline u8 nft_pf(const struct nft_pktinfo *pkt)
54 {
55 	return pkt->state->pf;
56 }
57 
58 static inline const struct net_device *nft_in(const struct nft_pktinfo *pkt)
59 {
60 	return pkt->state->in;
61 }
62 
63 static inline const struct net_device *nft_out(const struct nft_pktinfo *pkt)
64 {
65 	return pkt->state->out;
66 }
67 
68 static inline void nft_set_pktinfo(struct nft_pktinfo *pkt,
69 				   struct sk_buff *skb,
70 				   const struct nf_hook_state *state)
71 {
72 	pkt->skb = skb;
73 	pkt->state = state;
74 }
75 
76 static inline void nft_set_pktinfo_unspec(struct nft_pktinfo *pkt)
77 {
78 	pkt->tprot_set = false;
79 	pkt->tprot = 0;
80 	pkt->thoff = 0;
81 	pkt->fragoff = 0;
82 }
83 
84 /**
85  * 	struct nft_verdict - nf_tables verdict
86  *
87  * 	@code: nf_tables/netfilter verdict code
88  * 	@chain: destination chain for NFT_JUMP/NFT_GOTO
89  */
90 struct nft_verdict {
91 	u32				code;
92 	struct nft_chain		*chain;
93 };
94 
95 struct nft_data {
96 	union {
97 		u32			data[4];
98 		struct nft_verdict	verdict;
99 	};
100 } __attribute__((aligned(__alignof__(u64))));
101 
102 /**
103  *	struct nft_regs - nf_tables register set
104  *
105  *	@data: data registers
106  *	@verdict: verdict register
107  *
108  *	The first four data registers alias to the verdict register.
109  */
110 struct nft_regs {
111 	union {
112 		u32			data[20];
113 		struct nft_verdict	verdict;
114 	};
115 };
116 
117 /* Store/load an u8, u16 or u64 integer to/from the u32 data register.
118  *
119  * Note, when using concatenations, register allocation happens at 32-bit
120  * level. So for store instruction, pad the rest part with zero to avoid
121  * garbage values.
122  */
123 
124 static inline void nft_reg_store8(u32 *dreg, u8 val)
125 {
126 	*dreg = 0;
127 	*(u8 *)dreg = val;
128 }
129 
130 static inline u8 nft_reg_load8(const u32 *sreg)
131 {
132 	return *(u8 *)sreg;
133 }
134 
135 static inline void nft_reg_store16(u32 *dreg, u16 val)
136 {
137 	*dreg = 0;
138 	*(u16 *)dreg = val;
139 }
140 
141 static inline u16 nft_reg_load16(const u32 *sreg)
142 {
143 	return *(u16 *)sreg;
144 }
145 
146 static inline void nft_reg_store64(u32 *dreg, u64 val)
147 {
148 	put_unaligned(val, (u64 *)dreg);
149 }
150 
151 static inline u64 nft_reg_load64(const u32 *sreg)
152 {
153 	return get_unaligned((u64 *)sreg);
154 }
155 
156 static inline void nft_data_copy(u32 *dst, const struct nft_data *src,
157 				 unsigned int len)
158 {
159 	if (len % NFT_REG32_SIZE)
160 		dst[len / NFT_REG32_SIZE] = 0;
161 	memcpy(dst, src, len);
162 }
163 
164 /**
165  *	struct nft_ctx - nf_tables rule/set context
166  *
167  *	@net: net namespace
168  * 	@table: the table the chain is contained in
169  * 	@chain: the chain the rule is contained in
170  *	@nla: netlink attributes
171  *	@portid: netlink portID of the original message
172  *	@seq: netlink sequence number
173  *	@family: protocol family
174  *	@level: depth of the chains
175  *	@report: notify via unicast netlink message
176  */
177 struct nft_ctx {
178 	struct net			*net;
179 	struct nft_table		*table;
180 	struct nft_chain		*chain;
181 	const struct nlattr * const 	*nla;
182 	u32				portid;
183 	u32				seq;
184 	u16				flags;
185 	u8				family;
186 	u8				level;
187 	bool				report;
188 };
189 
190 struct nft_data_desc {
191 	enum nft_data_types		type;
192 	unsigned int			len;
193 };
194 
195 int nft_data_init(const struct nft_ctx *ctx,
196 		  struct nft_data *data, unsigned int size,
197 		  struct nft_data_desc *desc, const struct nlattr *nla);
198 void nft_data_hold(const struct nft_data *data, enum nft_data_types type);
199 void nft_data_release(const struct nft_data *data, enum nft_data_types type);
200 int nft_data_dump(struct sk_buff *skb, int attr, const struct nft_data *data,
201 		  enum nft_data_types type, unsigned int len);
202 
203 static inline enum nft_data_types nft_dreg_to_type(enum nft_registers reg)
204 {
205 	return reg == NFT_REG_VERDICT ? NFT_DATA_VERDICT : NFT_DATA_VALUE;
206 }
207 
208 static inline enum nft_registers nft_type_to_reg(enum nft_data_types type)
209 {
210 	return type == NFT_DATA_VERDICT ? NFT_REG_VERDICT : NFT_REG_1 * NFT_REG_SIZE / NFT_REG32_SIZE;
211 }
212 
213 int nft_parse_u32_check(const struct nlattr *attr, int max, u32 *dest);
214 int nft_dump_register(struct sk_buff *skb, unsigned int attr, unsigned int reg);
215 
216 int nft_parse_register_load(const struct nlattr *attr, u8 *sreg, u32 len);
217 int nft_parse_register_store(const struct nft_ctx *ctx,
218 			     const struct nlattr *attr, u8 *dreg,
219 			     const struct nft_data *data,
220 			     enum nft_data_types type, unsigned int len);
221 
222 /**
223  *	struct nft_userdata - user defined data associated with an object
224  *
225  *	@len: length of the data
226  *	@data: content
227  *
228  *	The presence of user data is indicated in an object specific fashion,
229  *	so a length of zero can't occur and the value "len" indicates data
230  *	of length len + 1.
231  */
232 struct nft_userdata {
233 	u8			len;
234 	unsigned char		data[];
235 };
236 
237 /**
238  *	struct nft_set_elem - generic representation of set elements
239  *
240  *	@key: element key
241  *	@key_end: closing element key
242  *	@priv: element private data and extensions
243  */
244 struct nft_set_elem {
245 	union {
246 		u32		buf[NFT_DATA_VALUE_MAXLEN / sizeof(u32)];
247 		struct nft_data	val;
248 	} key;
249 	union {
250 		u32		buf[NFT_DATA_VALUE_MAXLEN / sizeof(u32)];
251 		struct nft_data	val;
252 	} key_end;
253 	union {
254 		u32		buf[NFT_DATA_VALUE_MAXLEN / sizeof(u32)];
255 		struct nft_data val;
256 	} data;
257 	void			*priv;
258 };
259 
260 struct nft_set;
261 struct nft_set_iter {
262 	u8		genmask;
263 	unsigned int	count;
264 	unsigned int	skip;
265 	int		err;
266 	int		(*fn)(const struct nft_ctx *ctx,
267 			      struct nft_set *set,
268 			      const struct nft_set_iter *iter,
269 			      struct nft_set_elem *elem);
270 };
271 
272 /**
273  *	struct nft_set_desc - description of set elements
274  *
275  *	@klen: key length
276  *	@dlen: data length
277  *	@size: number of set elements
278  *	@field_len: length of each field in concatenation, bytes
279  *	@field_count: number of concatenated fields in element
280  *	@expr: set must support for expressions
281  */
282 struct nft_set_desc {
283 	unsigned int		klen;
284 	unsigned int		dlen;
285 	unsigned int		size;
286 	u8			field_len[NFT_REG32_COUNT];
287 	u8			field_count;
288 	bool			expr;
289 };
290 
291 /**
292  *	enum nft_set_class - performance class
293  *
294  *	@NFT_LOOKUP_O_1: constant, O(1)
295  *	@NFT_LOOKUP_O_LOG_N: logarithmic, O(log N)
296  *	@NFT_LOOKUP_O_N: linear, O(N)
297  */
298 enum nft_set_class {
299 	NFT_SET_CLASS_O_1,
300 	NFT_SET_CLASS_O_LOG_N,
301 	NFT_SET_CLASS_O_N,
302 };
303 
304 /**
305  *	struct nft_set_estimate - estimation of memory and performance
306  *				  characteristics
307  *
308  *	@size: required memory
309  *	@lookup: lookup performance class
310  *	@space: memory class
311  */
312 struct nft_set_estimate {
313 	u64			size;
314 	enum nft_set_class	lookup;
315 	enum nft_set_class	space;
316 };
317 
318 #define NFT_EXPR_MAXATTR		16
319 #define NFT_EXPR_SIZE(size)		(sizeof(struct nft_expr) + \
320 					 ALIGN(size, __alignof__(struct nft_expr)))
321 
322 /**
323  *	struct nft_expr - nf_tables expression
324  *
325  *	@ops: expression ops
326  *	@data: expression private data
327  */
328 struct nft_expr {
329 	const struct nft_expr_ops	*ops;
330 	unsigned char			data[]
331 		__attribute__((aligned(__alignof__(u64))));
332 };
333 
334 static inline void *nft_expr_priv(const struct nft_expr *expr)
335 {
336 	return (void *)expr->data;
337 }
338 
339 int nft_expr_clone(struct nft_expr *dst, struct nft_expr *src);
340 void nft_expr_destroy(const struct nft_ctx *ctx, struct nft_expr *expr);
341 int nft_expr_dump(struct sk_buff *skb, unsigned int attr,
342 		  const struct nft_expr *expr);
343 
344 struct nft_set_ext;
345 
346 /**
347  *	struct nft_set_ops - nf_tables set operations
348  *
349  *	@lookup: look up an element within the set
350  *	@update: update an element if exists, add it if doesn't exist
351  *	@delete: delete an element
352  *	@insert: insert new element into set
353  *	@activate: activate new element in the next generation
354  *	@deactivate: lookup for element and deactivate it in the next generation
355  *	@flush: deactivate element in the next generation
356  *	@remove: remove element from set
357  *	@walk: iterate over all set elements
358  *	@get: get set elements
359  *	@privsize: function to return size of set private data
360  *	@init: initialize private data of new set instance
361  *	@destroy: destroy private data of set instance
362  *	@elemsize: element private size
363  *
364  *	Operations lookup, update and delete have simpler interfaces, are faster
365  *	and currently only used in the packet path. All the rest are slower,
366  *	control plane functions.
367  */
368 struct nft_set_ops {
369 	bool				(*lookup)(const struct net *net,
370 						  const struct nft_set *set,
371 						  const u32 *key,
372 						  const struct nft_set_ext **ext);
373 	bool				(*update)(struct nft_set *set,
374 						  const u32 *key,
375 						  void *(*new)(struct nft_set *,
376 							       const struct nft_expr *,
377 							       struct nft_regs *),
378 						  const struct nft_expr *expr,
379 						  struct nft_regs *regs,
380 						  const struct nft_set_ext **ext);
381 	bool				(*delete)(const struct nft_set *set,
382 						  const u32 *key);
383 
384 	int				(*insert)(const struct net *net,
385 						  const struct nft_set *set,
386 						  const struct nft_set_elem *elem,
387 						  struct nft_set_ext **ext);
388 	void				(*activate)(const struct net *net,
389 						    const struct nft_set *set,
390 						    const struct nft_set_elem *elem);
391 	void *				(*deactivate)(const struct net *net,
392 						      const struct nft_set *set,
393 						      const struct nft_set_elem *elem);
394 	bool				(*flush)(const struct net *net,
395 						 const struct nft_set *set,
396 						 void *priv);
397 	void				(*remove)(const struct net *net,
398 						  const struct nft_set *set,
399 						  const struct nft_set_elem *elem);
400 	void				(*walk)(const struct nft_ctx *ctx,
401 						struct nft_set *set,
402 						struct nft_set_iter *iter);
403 	void *				(*get)(const struct net *net,
404 					       const struct nft_set *set,
405 					       const struct nft_set_elem *elem,
406 					       unsigned int flags);
407 
408 	u64				(*privsize)(const struct nlattr * const nla[],
409 						    const struct nft_set_desc *desc);
410 	bool				(*estimate)(const struct nft_set_desc *desc,
411 						    u32 features,
412 						    struct nft_set_estimate *est);
413 	int				(*init)(const struct nft_set *set,
414 						const struct nft_set_desc *desc,
415 						const struct nlattr * const nla[]);
416 	void				(*destroy)(const struct nft_set *set);
417 	void				(*gc_init)(const struct nft_set *set);
418 
419 	unsigned int			elemsize;
420 };
421 
422 /**
423  *      struct nft_set_type - nf_tables set type
424  *
425  *      @ops: set ops for this type
426  *      @features: features supported by the implementation
427  */
428 struct nft_set_type {
429 	const struct nft_set_ops	ops;
430 	u32				features;
431 };
432 #define to_set_type(o) container_of(o, struct nft_set_type, ops)
433 
434 struct nft_set_elem_expr {
435 	u8				size;
436 	unsigned char			data[]
437 		__attribute__((aligned(__alignof__(struct nft_expr))));
438 };
439 
440 #define nft_setelem_expr_at(__elem_expr, __offset)			\
441 	((struct nft_expr *)&__elem_expr->data[__offset])
442 
443 #define nft_setelem_expr_foreach(__expr, __elem_expr, __size)		\
444 	for (__expr = nft_setelem_expr_at(__elem_expr, 0), __size = 0;	\
445 	     __size < (__elem_expr)->size;				\
446 	     __size += (__expr)->ops->size, __expr = ((void *)(__expr)) + (__expr)->ops->size)
447 
448 #define NFT_SET_EXPR_MAX	2
449 
450 /**
451  * 	struct nft_set - nf_tables set instance
452  *
453  *	@list: table set list node
454  *	@bindings: list of set bindings
455  *	@table: table this set belongs to
456  *	@net: netnamespace this set belongs to
457  * 	@name: name of the set
458  *	@handle: unique handle of the set
459  * 	@ktype: key type (numeric type defined by userspace, not used in the kernel)
460  * 	@dtype: data type (verdict or numeric type defined by userspace)
461  * 	@objtype: object type (see NFT_OBJECT_* definitions)
462  * 	@size: maximum set size
463  *	@field_len: length of each field in concatenation, bytes
464  *	@field_count: number of concatenated fields in element
465  *	@use: number of rules references to this set
466  * 	@nelems: number of elements
467  * 	@ndeact: number of deactivated elements queued for removal
468  *	@timeout: default timeout value in jiffies
469  * 	@gc_int: garbage collection interval in msecs
470  *	@policy: set parameterization (see enum nft_set_policies)
471  *	@udlen: user data length
472  *	@udata: user data
473  *	@expr: stateful expression
474  * 	@ops: set ops
475  * 	@flags: set flags
476  *	@genmask: generation mask
477  * 	@klen: key length
478  * 	@dlen: data length
479  * 	@data: private set data
480  */
481 struct nft_set {
482 	struct list_head		list;
483 	struct list_head		bindings;
484 	struct nft_table		*table;
485 	possible_net_t			net;
486 	char				*name;
487 	u64				handle;
488 	u32				ktype;
489 	u32				dtype;
490 	u32				objtype;
491 	u32				size;
492 	u8				field_len[NFT_REG32_COUNT];
493 	u8				field_count;
494 	u32				use;
495 	atomic_t			nelems;
496 	u32				ndeact;
497 	u64				timeout;
498 	u32				gc_int;
499 	u16				policy;
500 	u16				udlen;
501 	unsigned char			*udata;
502 	/* runtime data below here */
503 	const struct nft_set_ops	*ops ____cacheline_aligned;
504 	u16				flags:14,
505 					genmask:2;
506 	u8				klen;
507 	u8				dlen;
508 	u8				num_exprs;
509 	struct nft_expr			*exprs[NFT_SET_EXPR_MAX];
510 	struct list_head		catchall_list;
511 	unsigned char			data[]
512 		__attribute__((aligned(__alignof__(u64))));
513 };
514 
515 static inline bool nft_set_is_anonymous(const struct nft_set *set)
516 {
517 	return set->flags & NFT_SET_ANONYMOUS;
518 }
519 
520 static inline void *nft_set_priv(const struct nft_set *set)
521 {
522 	return (void *)set->data;
523 }
524 
525 static inline struct nft_set *nft_set_container_of(const void *priv)
526 {
527 	return (void *)priv - offsetof(struct nft_set, data);
528 }
529 
530 struct nft_set *nft_set_lookup_global(const struct net *net,
531 				      const struct nft_table *table,
532 				      const struct nlattr *nla_set_name,
533 				      const struct nlattr *nla_set_id,
534 				      u8 genmask);
535 
536 struct nft_set_ext *nft_set_catchall_lookup(const struct net *net,
537 					    const struct nft_set *set);
538 void *nft_set_catchall_gc(const struct nft_set *set);
539 
540 static inline unsigned long nft_set_gc_interval(const struct nft_set *set)
541 {
542 	return set->gc_int ? msecs_to_jiffies(set->gc_int) : HZ;
543 }
544 
545 /**
546  *	struct nft_set_binding - nf_tables set binding
547  *
548  *	@list: set bindings list node
549  *	@chain: chain containing the rule bound to the set
550  *	@flags: set action flags
551  *
552  *	A set binding contains all information necessary for validation
553  *	of new elements added to a bound set.
554  */
555 struct nft_set_binding {
556 	struct list_head		list;
557 	const struct nft_chain		*chain;
558 	u32				flags;
559 };
560 
561 enum nft_trans_phase;
562 void nf_tables_deactivate_set(const struct nft_ctx *ctx, struct nft_set *set,
563 			      struct nft_set_binding *binding,
564 			      enum nft_trans_phase phase);
565 int nf_tables_bind_set(const struct nft_ctx *ctx, struct nft_set *set,
566 		       struct nft_set_binding *binding);
567 void nf_tables_destroy_set(const struct nft_ctx *ctx, struct nft_set *set);
568 
569 /**
570  *	enum nft_set_extensions - set extension type IDs
571  *
572  *	@NFT_SET_EXT_KEY: element key
573  *	@NFT_SET_EXT_KEY_END: upper bound element key, for ranges
574  *	@NFT_SET_EXT_DATA: mapping data
575  *	@NFT_SET_EXT_FLAGS: element flags
576  *	@NFT_SET_EXT_TIMEOUT: element timeout
577  *	@NFT_SET_EXT_EXPIRATION: element expiration time
578  *	@NFT_SET_EXT_USERDATA: user data associated with the element
579  *	@NFT_SET_EXT_EXPRESSIONS: expressions assiciated with the element
580  *	@NFT_SET_EXT_OBJREF: stateful object reference associated with element
581  *	@NFT_SET_EXT_NUM: number of extension types
582  */
583 enum nft_set_extensions {
584 	NFT_SET_EXT_KEY,
585 	NFT_SET_EXT_KEY_END,
586 	NFT_SET_EXT_DATA,
587 	NFT_SET_EXT_FLAGS,
588 	NFT_SET_EXT_TIMEOUT,
589 	NFT_SET_EXT_EXPIRATION,
590 	NFT_SET_EXT_USERDATA,
591 	NFT_SET_EXT_EXPRESSIONS,
592 	NFT_SET_EXT_OBJREF,
593 	NFT_SET_EXT_NUM
594 };
595 
596 /**
597  *	struct nft_set_ext_type - set extension type
598  *
599  * 	@len: fixed part length of the extension
600  * 	@align: alignment requirements of the extension
601  */
602 struct nft_set_ext_type {
603 	u8	len;
604 	u8	align;
605 };
606 
607 extern const struct nft_set_ext_type nft_set_ext_types[];
608 
609 /**
610  *	struct nft_set_ext_tmpl - set extension template
611  *
612  *	@len: length of extension area
613  *	@offset: offsets of individual extension types
614  */
615 struct nft_set_ext_tmpl {
616 	u16	len;
617 	u8	offset[NFT_SET_EXT_NUM];
618 };
619 
620 /**
621  *	struct nft_set_ext - set extensions
622  *
623  *	@genmask: generation mask
624  *	@offset: offsets of individual extension types
625  *	@data: beginning of extension data
626  */
627 struct nft_set_ext {
628 	u8	genmask;
629 	u8	offset[NFT_SET_EXT_NUM];
630 	char	data[];
631 };
632 
633 static inline void nft_set_ext_prepare(struct nft_set_ext_tmpl *tmpl)
634 {
635 	memset(tmpl, 0, sizeof(*tmpl));
636 	tmpl->len = sizeof(struct nft_set_ext);
637 }
638 
639 static inline void nft_set_ext_add_length(struct nft_set_ext_tmpl *tmpl, u8 id,
640 					  unsigned int len)
641 {
642 	tmpl->len	 = ALIGN(tmpl->len, nft_set_ext_types[id].align);
643 	BUG_ON(tmpl->len > U8_MAX);
644 	tmpl->offset[id] = tmpl->len;
645 	tmpl->len	+= nft_set_ext_types[id].len + len;
646 }
647 
648 static inline void nft_set_ext_add(struct nft_set_ext_tmpl *tmpl, u8 id)
649 {
650 	nft_set_ext_add_length(tmpl, id, 0);
651 }
652 
653 static inline void nft_set_ext_init(struct nft_set_ext *ext,
654 				    const struct nft_set_ext_tmpl *tmpl)
655 {
656 	memcpy(ext->offset, tmpl->offset, sizeof(ext->offset));
657 }
658 
659 static inline bool __nft_set_ext_exists(const struct nft_set_ext *ext, u8 id)
660 {
661 	return !!ext->offset[id];
662 }
663 
664 static inline bool nft_set_ext_exists(const struct nft_set_ext *ext, u8 id)
665 {
666 	return ext && __nft_set_ext_exists(ext, id);
667 }
668 
669 static inline void *nft_set_ext(const struct nft_set_ext *ext, u8 id)
670 {
671 	return (void *)ext + ext->offset[id];
672 }
673 
674 static inline struct nft_data *nft_set_ext_key(const struct nft_set_ext *ext)
675 {
676 	return nft_set_ext(ext, NFT_SET_EXT_KEY);
677 }
678 
679 static inline struct nft_data *nft_set_ext_key_end(const struct nft_set_ext *ext)
680 {
681 	return nft_set_ext(ext, NFT_SET_EXT_KEY_END);
682 }
683 
684 static inline struct nft_data *nft_set_ext_data(const struct nft_set_ext *ext)
685 {
686 	return nft_set_ext(ext, NFT_SET_EXT_DATA);
687 }
688 
689 static inline u8 *nft_set_ext_flags(const struct nft_set_ext *ext)
690 {
691 	return nft_set_ext(ext, NFT_SET_EXT_FLAGS);
692 }
693 
694 static inline u64 *nft_set_ext_timeout(const struct nft_set_ext *ext)
695 {
696 	return nft_set_ext(ext, NFT_SET_EXT_TIMEOUT);
697 }
698 
699 static inline u64 *nft_set_ext_expiration(const struct nft_set_ext *ext)
700 {
701 	return nft_set_ext(ext, NFT_SET_EXT_EXPIRATION);
702 }
703 
704 static inline struct nft_userdata *nft_set_ext_userdata(const struct nft_set_ext *ext)
705 {
706 	return nft_set_ext(ext, NFT_SET_EXT_USERDATA);
707 }
708 
709 static inline struct nft_set_elem_expr *nft_set_ext_expr(const struct nft_set_ext *ext)
710 {
711 	return nft_set_ext(ext, NFT_SET_EXT_EXPRESSIONS);
712 }
713 
714 static inline bool nft_set_elem_expired(const struct nft_set_ext *ext)
715 {
716 	return nft_set_ext_exists(ext, NFT_SET_EXT_EXPIRATION) &&
717 	       time_is_before_eq_jiffies64(*nft_set_ext_expiration(ext));
718 }
719 
720 static inline struct nft_set_ext *nft_set_elem_ext(const struct nft_set *set,
721 						   void *elem)
722 {
723 	return elem + set->ops->elemsize;
724 }
725 
726 static inline struct nft_object **nft_set_ext_obj(const struct nft_set_ext *ext)
727 {
728 	return nft_set_ext(ext, NFT_SET_EXT_OBJREF);
729 }
730 
731 struct nft_expr *nft_set_elem_expr_alloc(const struct nft_ctx *ctx,
732 					 const struct nft_set *set,
733 					 const struct nlattr *attr);
734 
735 void *nft_set_elem_init(const struct nft_set *set,
736 			const struct nft_set_ext_tmpl *tmpl,
737 			const u32 *key, const u32 *key_end, const u32 *data,
738 			u64 timeout, u64 expiration, gfp_t gfp);
739 int nft_set_elem_expr_clone(const struct nft_ctx *ctx, struct nft_set *set,
740 			    struct nft_expr *expr_array[]);
741 void nft_set_elem_destroy(const struct nft_set *set, void *elem,
742 			  bool destroy_expr);
743 
744 /**
745  *	struct nft_set_gc_batch_head - nf_tables set garbage collection batch
746  *
747  *	@rcu: rcu head
748  *	@set: set the elements belong to
749  *	@cnt: count of elements
750  */
751 struct nft_set_gc_batch_head {
752 	struct rcu_head			rcu;
753 	const struct nft_set		*set;
754 	unsigned int			cnt;
755 };
756 
757 #define NFT_SET_GC_BATCH_SIZE	((PAGE_SIZE -				  \
758 				  sizeof(struct nft_set_gc_batch_head)) / \
759 				 sizeof(void *))
760 
761 /**
762  *	struct nft_set_gc_batch - nf_tables set garbage collection batch
763  *
764  * 	@head: GC batch head
765  * 	@elems: garbage collection elements
766  */
767 struct nft_set_gc_batch {
768 	struct nft_set_gc_batch_head	head;
769 	void				*elems[NFT_SET_GC_BATCH_SIZE];
770 };
771 
772 struct nft_set_gc_batch *nft_set_gc_batch_alloc(const struct nft_set *set,
773 						gfp_t gfp);
774 void nft_set_gc_batch_release(struct rcu_head *rcu);
775 
776 static inline void nft_set_gc_batch_complete(struct nft_set_gc_batch *gcb)
777 {
778 	if (gcb != NULL)
779 		call_rcu(&gcb->head.rcu, nft_set_gc_batch_release);
780 }
781 
782 static inline struct nft_set_gc_batch *
783 nft_set_gc_batch_check(const struct nft_set *set, struct nft_set_gc_batch *gcb,
784 		       gfp_t gfp)
785 {
786 	if (gcb != NULL) {
787 		if (gcb->head.cnt + 1 < ARRAY_SIZE(gcb->elems))
788 			return gcb;
789 		nft_set_gc_batch_complete(gcb);
790 	}
791 	return nft_set_gc_batch_alloc(set, gfp);
792 }
793 
794 static inline void nft_set_gc_batch_add(struct nft_set_gc_batch *gcb,
795 					void *elem)
796 {
797 	gcb->elems[gcb->head.cnt++] = elem;
798 }
799 
800 struct nft_expr_ops;
801 /**
802  *	struct nft_expr_type - nf_tables expression type
803  *
804  *	@select_ops: function to select nft_expr_ops
805  *	@release_ops: release nft_expr_ops
806  *	@ops: default ops, used when no select_ops functions is present
807  *	@list: used internally
808  *	@name: Identifier
809  *	@owner: module reference
810  *	@policy: netlink attribute policy
811  *	@maxattr: highest netlink attribute number
812  *	@family: address family for AF-specific types
813  *	@flags: expression type flags
814  */
815 struct nft_expr_type {
816 	const struct nft_expr_ops	*(*select_ops)(const struct nft_ctx *,
817 						       const struct nlattr * const tb[]);
818 	void				(*release_ops)(const struct nft_expr_ops *ops);
819 	const struct nft_expr_ops	*ops;
820 	struct list_head		list;
821 	const char			*name;
822 	struct module			*owner;
823 	const struct nla_policy		*policy;
824 	unsigned int			maxattr;
825 	u8				family;
826 	u8				flags;
827 };
828 
829 #define NFT_EXPR_STATEFUL		0x1
830 #define NFT_EXPR_GC			0x2
831 
832 enum nft_trans_phase {
833 	NFT_TRANS_PREPARE,
834 	NFT_TRANS_ABORT,
835 	NFT_TRANS_COMMIT,
836 	NFT_TRANS_RELEASE
837 };
838 
839 struct nft_flow_rule;
840 struct nft_offload_ctx;
841 
842 /**
843  *	struct nft_expr_ops - nf_tables expression operations
844  *
845  *	@eval: Expression evaluation function
846  *	@size: full expression size, including private data size
847  *	@init: initialization function
848  *	@activate: activate expression in the next generation
849  *	@deactivate: deactivate expression in next generation
850  *	@destroy: destruction function, called after synchronize_rcu
851  *	@dump: function to dump parameters
852  *	@type: expression type
853  *	@validate: validate expression, called during loop detection
854  *	@data: extra data to attach to this expression operation
855  */
856 struct nft_expr_ops {
857 	void				(*eval)(const struct nft_expr *expr,
858 						struct nft_regs *regs,
859 						const struct nft_pktinfo *pkt);
860 	int				(*clone)(struct nft_expr *dst,
861 						 const struct nft_expr *src);
862 	unsigned int			size;
863 
864 	int				(*init)(const struct nft_ctx *ctx,
865 						const struct nft_expr *expr,
866 						const struct nlattr * const tb[]);
867 	void				(*activate)(const struct nft_ctx *ctx,
868 						    const struct nft_expr *expr);
869 	void				(*deactivate)(const struct nft_ctx *ctx,
870 						      const struct nft_expr *expr,
871 						      enum nft_trans_phase phase);
872 	void				(*destroy)(const struct nft_ctx *ctx,
873 						   const struct nft_expr *expr);
874 	void				(*destroy_clone)(const struct nft_ctx *ctx,
875 							 const struct nft_expr *expr);
876 	int				(*dump)(struct sk_buff *skb,
877 						const struct nft_expr *expr);
878 	int				(*validate)(const struct nft_ctx *ctx,
879 						    const struct nft_expr *expr,
880 						    const struct nft_data **data);
881 	bool				(*gc)(struct net *net,
882 					      const struct nft_expr *expr);
883 	int				(*offload)(struct nft_offload_ctx *ctx,
884 						   struct nft_flow_rule *flow,
885 						   const struct nft_expr *expr);
886 	void				(*offload_stats)(struct nft_expr *expr,
887 							 const struct flow_stats *stats);
888 	u32				offload_flags;
889 	const struct nft_expr_type	*type;
890 	void				*data;
891 };
892 
893 /**
894  *	struct nft_rule - nf_tables rule
895  *
896  *	@list: used internally
897  *	@handle: rule handle
898  *	@genmask: generation mask
899  *	@dlen: length of expression data
900  *	@udata: user data is appended to the rule
901  *	@data: expression data
902  */
903 struct nft_rule {
904 	struct list_head		list;
905 	u64				handle:42,
906 					genmask:2,
907 					dlen:12,
908 					udata:1;
909 	unsigned char			data[]
910 		__attribute__((aligned(__alignof__(struct nft_expr))));
911 };
912 
913 static inline struct nft_expr *nft_expr_first(const struct nft_rule *rule)
914 {
915 	return (struct nft_expr *)&rule->data[0];
916 }
917 
918 static inline struct nft_expr *nft_expr_next(const struct nft_expr *expr)
919 {
920 	return ((void *)expr) + expr->ops->size;
921 }
922 
923 static inline struct nft_expr *nft_expr_last(const struct nft_rule *rule)
924 {
925 	return (struct nft_expr *)&rule->data[rule->dlen];
926 }
927 
928 static inline bool nft_expr_more(const struct nft_rule *rule,
929 				 const struct nft_expr *expr)
930 {
931 	return expr != nft_expr_last(rule) && expr->ops;
932 }
933 
934 static inline struct nft_userdata *nft_userdata(const struct nft_rule *rule)
935 {
936 	return (void *)&rule->data[rule->dlen];
937 }
938 
939 void nf_tables_rule_release(const struct nft_ctx *ctx, struct nft_rule *rule);
940 
941 static inline void nft_set_elem_update_expr(const struct nft_set_ext *ext,
942 					    struct nft_regs *regs,
943 					    const struct nft_pktinfo *pkt)
944 {
945 	struct nft_set_elem_expr *elem_expr;
946 	struct nft_expr *expr;
947 	u32 size;
948 
949 	if (__nft_set_ext_exists(ext, NFT_SET_EXT_EXPRESSIONS)) {
950 		elem_expr = nft_set_ext_expr(ext);
951 		nft_setelem_expr_foreach(expr, elem_expr, size) {
952 			expr->ops->eval(expr, regs, pkt);
953 			if (regs->verdict.code == NFT_BREAK)
954 				return;
955 		}
956 	}
957 }
958 
959 /*
960  * The last pointer isn't really necessary, but the compiler isn't able to
961  * determine that the result of nft_expr_last() is always the same since it
962  * can't assume that the dlen value wasn't changed within calls in the loop.
963  */
964 #define nft_rule_for_each_expr(expr, last, rule) \
965 	for ((expr) = nft_expr_first(rule), (last) = nft_expr_last(rule); \
966 	     (expr) != (last); \
967 	     (expr) = nft_expr_next(expr))
968 
969 #define NFT_CHAIN_POLICY_UNSET		U8_MAX
970 
971 /**
972  *	struct nft_chain - nf_tables chain
973  *
974  *	@rules: list of rules in the chain
975  *	@list: used internally
976  *	@rhlhead: used internally
977  *	@table: table that this chain belongs to
978  *	@handle: chain handle
979  *	@use: number of jump references to this chain
980  *	@flags: bitmask of enum nft_chain_flags
981  *	@name: name of the chain
982  */
983 struct nft_chain {
984 	struct nft_rule			*__rcu *rules_gen_0;
985 	struct nft_rule			*__rcu *rules_gen_1;
986 	struct list_head		rules;
987 	struct list_head		list;
988 	struct rhlist_head		rhlhead;
989 	struct nft_table		*table;
990 	u64				handle;
991 	u32				use;
992 	u8				flags:5,
993 					bound:1,
994 					genmask:2;
995 	char				*name;
996 	u16				udlen;
997 	u8				*udata;
998 
999 	/* Only used during control plane commit phase: */
1000 	struct nft_rule			**rules_next;
1001 };
1002 
1003 int nft_chain_validate(const struct nft_ctx *ctx, const struct nft_chain *chain);
1004 
1005 enum nft_chain_types {
1006 	NFT_CHAIN_T_DEFAULT = 0,
1007 	NFT_CHAIN_T_ROUTE,
1008 	NFT_CHAIN_T_NAT,
1009 	NFT_CHAIN_T_MAX
1010 };
1011 
1012 /**
1013  * 	struct nft_chain_type - nf_tables chain type info
1014  *
1015  * 	@name: name of the type
1016  * 	@type: numeric identifier
1017  * 	@family: address family
1018  * 	@owner: module owner
1019  * 	@hook_mask: mask of valid hooks
1020  * 	@hooks: array of hook functions
1021  *	@ops_register: base chain register function
1022  *	@ops_unregister: base chain unregister function
1023  */
1024 struct nft_chain_type {
1025 	const char			*name;
1026 	enum nft_chain_types		type;
1027 	int				family;
1028 	struct module			*owner;
1029 	unsigned int			hook_mask;
1030 	nf_hookfn			*hooks[NFT_MAX_HOOKS];
1031 	int				(*ops_register)(struct net *net, const struct nf_hook_ops *ops);
1032 	void				(*ops_unregister)(struct net *net, const struct nf_hook_ops *ops);
1033 };
1034 
1035 int nft_chain_validate_dependency(const struct nft_chain *chain,
1036 				  enum nft_chain_types type);
1037 int nft_chain_validate_hooks(const struct nft_chain *chain,
1038                              unsigned int hook_flags);
1039 
1040 static inline bool nft_chain_is_bound(struct nft_chain *chain)
1041 {
1042 	return (chain->flags & NFT_CHAIN_BINDING) && chain->bound;
1043 }
1044 
1045 void nft_chain_del(struct nft_chain *chain);
1046 void nf_tables_chain_destroy(struct nft_ctx *ctx);
1047 
1048 struct nft_stats {
1049 	u64			bytes;
1050 	u64			pkts;
1051 	struct u64_stats_sync	syncp;
1052 };
1053 
1054 struct nft_hook {
1055 	struct list_head	list;
1056 	bool			inactive;
1057 	struct nf_hook_ops	ops;
1058 	struct rcu_head		rcu;
1059 };
1060 
1061 /**
1062  *	struct nft_base_chain - nf_tables base chain
1063  *
1064  *	@ops: netfilter hook ops
1065  *	@hook_list: list of netfilter hooks (for NFPROTO_NETDEV family)
1066  *	@type: chain type
1067  *	@policy: default policy
1068  *	@stats: per-cpu chain stats
1069  *	@chain: the chain
1070  *	@flow_block: flow block (for hardware offload)
1071  */
1072 struct nft_base_chain {
1073 	struct nf_hook_ops		ops;
1074 	struct list_head		hook_list;
1075 	const struct nft_chain_type	*type;
1076 	u8				policy;
1077 	u8				flags;
1078 	struct nft_stats __percpu	*stats;
1079 	struct nft_chain		chain;
1080 	struct flow_block		flow_block;
1081 };
1082 
1083 static inline struct nft_base_chain *nft_base_chain(const struct nft_chain *chain)
1084 {
1085 	return container_of(chain, struct nft_base_chain, chain);
1086 }
1087 
1088 static inline bool nft_is_base_chain(const struct nft_chain *chain)
1089 {
1090 	return chain->flags & NFT_CHAIN_BASE;
1091 }
1092 
1093 int __nft_release_basechain(struct nft_ctx *ctx);
1094 
1095 unsigned int nft_do_chain(struct nft_pktinfo *pkt, void *priv);
1096 
1097 /**
1098  *	struct nft_table - nf_tables table
1099  *
1100  *	@list: used internally
1101  *	@chains_ht: chains in the table
1102  *	@chains: same, for stable walks
1103  *	@sets: sets in the table
1104  *	@objects: stateful objects in the table
1105  *	@flowtables: flow tables in the table
1106  *	@hgenerator: handle generator state
1107  *	@handle: table handle
1108  *	@use: number of chain references to this table
1109  *	@flags: table flag (see enum nft_table_flags)
1110  *	@genmask: generation mask
1111  *	@afinfo: address family info
1112  *	@name: name of the table
1113  */
1114 struct nft_table {
1115 	struct list_head		list;
1116 	struct rhltable			chains_ht;
1117 	struct list_head		chains;
1118 	struct list_head		sets;
1119 	struct list_head		objects;
1120 	struct list_head		flowtables;
1121 	u64				hgenerator;
1122 	u64				handle;
1123 	u32				use;
1124 	u16				family:6,
1125 					flags:8,
1126 					genmask:2;
1127 	u32				nlpid;
1128 	char				*name;
1129 	u16				udlen;
1130 	u8				*udata;
1131 };
1132 
1133 static inline bool nft_table_has_owner(const struct nft_table *table)
1134 {
1135 	return table->flags & NFT_TABLE_F_OWNER;
1136 }
1137 
1138 static inline bool nft_base_chain_netdev(int family, u32 hooknum)
1139 {
1140 	return family == NFPROTO_NETDEV ||
1141 	       (family == NFPROTO_INET && hooknum == NF_INET_INGRESS);
1142 }
1143 
1144 void nft_register_chain_type(const struct nft_chain_type *);
1145 void nft_unregister_chain_type(const struct nft_chain_type *);
1146 
1147 int nft_register_expr(struct nft_expr_type *);
1148 void nft_unregister_expr(struct nft_expr_type *);
1149 
1150 int nft_verdict_dump(struct sk_buff *skb, int type,
1151 		     const struct nft_verdict *v);
1152 
1153 /**
1154  *	struct nft_object_hash_key - key to lookup nft_object
1155  *
1156  *	@name: name of the stateful object to look up
1157  *	@table: table the object belongs to
1158  */
1159 struct nft_object_hash_key {
1160 	const char                      *name;
1161 	const struct nft_table          *table;
1162 };
1163 
1164 /**
1165  *	struct nft_object - nf_tables stateful object
1166  *
1167  *	@list: table stateful object list node
1168  *	@key:  keys that identify this object
1169  *	@rhlhead: nft_objname_ht node
1170  *	@genmask: generation mask
1171  *	@use: number of references to this stateful object
1172  *	@handle: unique object handle
1173  *	@ops: object operations
1174  *	@data: object data, layout depends on type
1175  */
1176 struct nft_object {
1177 	struct list_head		list;
1178 	struct rhlist_head		rhlhead;
1179 	struct nft_object_hash_key	key;
1180 	u32				genmask:2,
1181 					use:30;
1182 	u64				handle;
1183 	u16				udlen;
1184 	u8				*udata;
1185 	/* runtime data below here */
1186 	const struct nft_object_ops	*ops ____cacheline_aligned;
1187 	unsigned char			data[]
1188 		__attribute__((aligned(__alignof__(u64))));
1189 };
1190 
1191 static inline void *nft_obj_data(const struct nft_object *obj)
1192 {
1193 	return (void *)obj->data;
1194 }
1195 
1196 #define nft_expr_obj(expr)	*((struct nft_object **)nft_expr_priv(expr))
1197 
1198 struct nft_object *nft_obj_lookup(const struct net *net,
1199 				  const struct nft_table *table,
1200 				  const struct nlattr *nla, u32 objtype,
1201 				  u8 genmask);
1202 
1203 void nft_obj_notify(struct net *net, const struct nft_table *table,
1204 		    struct nft_object *obj, u32 portid, u32 seq,
1205 		    int event, int family, int report, gfp_t gfp);
1206 
1207 /**
1208  *	struct nft_object_type - stateful object type
1209  *
1210  *	@select_ops: function to select nft_object_ops
1211  *	@ops: default ops, used when no select_ops functions is present
1212  *	@list: list node in list of object types
1213  *	@type: stateful object numeric type
1214  *	@owner: module owner
1215  *	@maxattr: maximum netlink attribute
1216  *	@policy: netlink attribute policy
1217  */
1218 struct nft_object_type {
1219 	const struct nft_object_ops	*(*select_ops)(const struct nft_ctx *,
1220 						       const struct nlattr * const tb[]);
1221 	const struct nft_object_ops	*ops;
1222 	struct list_head		list;
1223 	u32				type;
1224 	unsigned int                    maxattr;
1225 	struct module			*owner;
1226 	const struct nla_policy		*policy;
1227 };
1228 
1229 /**
1230  *	struct nft_object_ops - stateful object operations
1231  *
1232  *	@eval: stateful object evaluation function
1233  *	@size: stateful object size
1234  *	@init: initialize object from netlink attributes
1235  *	@destroy: release existing stateful object
1236  *	@dump: netlink dump stateful object
1237  *	@update: update stateful object
1238  */
1239 struct nft_object_ops {
1240 	void				(*eval)(struct nft_object *obj,
1241 						struct nft_regs *regs,
1242 						const struct nft_pktinfo *pkt);
1243 	unsigned int			size;
1244 	int				(*init)(const struct nft_ctx *ctx,
1245 						const struct nlattr *const tb[],
1246 						struct nft_object *obj);
1247 	void				(*destroy)(const struct nft_ctx *ctx,
1248 						   struct nft_object *obj);
1249 	int				(*dump)(struct sk_buff *skb,
1250 						struct nft_object *obj,
1251 						bool reset);
1252 	void				(*update)(struct nft_object *obj,
1253 						  struct nft_object *newobj);
1254 	const struct nft_object_type	*type;
1255 };
1256 
1257 int nft_register_obj(struct nft_object_type *obj_type);
1258 void nft_unregister_obj(struct nft_object_type *obj_type);
1259 
1260 #define NFT_NETDEVICE_MAX	256
1261 
1262 /**
1263  *	struct nft_flowtable - nf_tables flow table
1264  *
1265  *	@list: flow table list node in table list
1266  * 	@table: the table the flow table is contained in
1267  *	@name: name of this flow table
1268  *	@hooknum: hook number
1269  *	@ops_len: number of hooks in array
1270  *	@genmask: generation mask
1271  *	@use: number of references to this flow table
1272  * 	@handle: unique object handle
1273  *	@dev_name: array of device names
1274  *	@data: rhashtable and garbage collector
1275  * 	@ops: array of hooks
1276  */
1277 struct nft_flowtable {
1278 	struct list_head		list;
1279 	struct nft_table		*table;
1280 	char				*name;
1281 	int				hooknum;
1282 	int				ops_len;
1283 	u32				genmask:2,
1284 					use:30;
1285 	u64				handle;
1286 	/* runtime data below here */
1287 	struct list_head		hook_list ____cacheline_aligned;
1288 	struct nf_flowtable		data;
1289 };
1290 
1291 struct nft_flowtable *nft_flowtable_lookup(const struct nft_table *table,
1292 					   const struct nlattr *nla,
1293 					   u8 genmask);
1294 
1295 void nf_tables_deactivate_flowtable(const struct nft_ctx *ctx,
1296 				    struct nft_flowtable *flowtable,
1297 				    enum nft_trans_phase phase);
1298 
1299 void nft_register_flowtable_type(struct nf_flowtable_type *type);
1300 void nft_unregister_flowtable_type(struct nf_flowtable_type *type);
1301 
1302 /**
1303  *	struct nft_traceinfo - nft tracing information and state
1304  *
1305  *	@pkt: pktinfo currently processed
1306  *	@basechain: base chain currently processed
1307  *	@chain: chain currently processed
1308  *	@rule:  rule that was evaluated
1309  *	@verdict: verdict given by rule
1310  *	@type: event type (enum nft_trace_types)
1311  *	@packet_dumped: packet headers sent in a previous traceinfo message
1312  *	@trace: other struct members are initialised
1313  */
1314 struct nft_traceinfo {
1315 	const struct nft_pktinfo	*pkt;
1316 	const struct nft_base_chain	*basechain;
1317 	const struct nft_chain		*chain;
1318 	const struct nft_rule		*rule;
1319 	const struct nft_verdict	*verdict;
1320 	enum nft_trace_types		type;
1321 	bool				packet_dumped;
1322 	bool				trace;
1323 };
1324 
1325 void nft_trace_init(struct nft_traceinfo *info, const struct nft_pktinfo *pkt,
1326 		    const struct nft_verdict *verdict,
1327 		    const struct nft_chain *basechain);
1328 
1329 void nft_trace_notify(struct nft_traceinfo *info);
1330 
1331 #define MODULE_ALIAS_NFT_CHAIN(family, name) \
1332 	MODULE_ALIAS("nft-chain-" __stringify(family) "-" name)
1333 
1334 #define MODULE_ALIAS_NFT_AF_EXPR(family, name) \
1335 	MODULE_ALIAS("nft-expr-" __stringify(family) "-" name)
1336 
1337 #define MODULE_ALIAS_NFT_EXPR(name) \
1338 	MODULE_ALIAS("nft-expr-" name)
1339 
1340 #define MODULE_ALIAS_NFT_OBJ(type) \
1341 	MODULE_ALIAS("nft-obj-" __stringify(type))
1342 
1343 #if IS_ENABLED(CONFIG_NF_TABLES)
1344 
1345 /*
1346  * The gencursor defines two generations, the currently active and the
1347  * next one. Objects contain a bitmask of 2 bits specifying the generations
1348  * they're active in. A set bit means they're inactive in the generation
1349  * represented by that bit.
1350  *
1351  * New objects start out as inactive in the current and active in the
1352  * next generation. When committing the ruleset the bitmask is cleared,
1353  * meaning they're active in all generations. When removing an object,
1354  * it is set inactive in the next generation. After committing the ruleset,
1355  * the objects are removed.
1356  */
1357 static inline unsigned int nft_gencursor_next(const struct net *net)
1358 {
1359 	return net->nft.gencursor + 1 == 1 ? 1 : 0;
1360 }
1361 
1362 static inline u8 nft_genmask_next(const struct net *net)
1363 {
1364 	return 1 << nft_gencursor_next(net);
1365 }
1366 
1367 static inline u8 nft_genmask_cur(const struct net *net)
1368 {
1369 	/* Use READ_ONCE() to prevent refetching the value for atomicity */
1370 	return 1 << READ_ONCE(net->nft.gencursor);
1371 }
1372 
1373 #define NFT_GENMASK_ANY		((1 << 0) | (1 << 1))
1374 
1375 /*
1376  * Generic transaction helpers
1377  */
1378 
1379 /* Check if this object is currently active. */
1380 #define nft_is_active(__net, __obj)				\
1381 	(((__obj)->genmask & nft_genmask_cur(__net)) == 0)
1382 
1383 /* Check if this object is active in the next generation. */
1384 #define nft_is_active_next(__net, __obj)			\
1385 	(((__obj)->genmask & nft_genmask_next(__net)) == 0)
1386 
1387 /* This object becomes active in the next generation. */
1388 #define nft_activate_next(__net, __obj)				\
1389 	(__obj)->genmask = nft_genmask_cur(__net)
1390 
1391 /* This object becomes inactive in the next generation. */
1392 #define nft_deactivate_next(__net, __obj)			\
1393         (__obj)->genmask = nft_genmask_next(__net)
1394 
1395 /* After committing the ruleset, clear the stale generation bit. */
1396 #define nft_clear(__net, __obj)					\
1397 	(__obj)->genmask &= ~nft_genmask_next(__net)
1398 #define nft_active_genmask(__obj, __genmask)			\
1399 	!((__obj)->genmask & __genmask)
1400 
1401 /*
1402  * Set element transaction helpers
1403  */
1404 
1405 static inline bool nft_set_elem_active(const struct nft_set_ext *ext,
1406 				       u8 genmask)
1407 {
1408 	return !(ext->genmask & genmask);
1409 }
1410 
1411 static inline void nft_set_elem_change_active(const struct net *net,
1412 					      const struct nft_set *set,
1413 					      struct nft_set_ext *ext)
1414 {
1415 	ext->genmask ^= nft_genmask_next(net);
1416 }
1417 
1418 #endif /* IS_ENABLED(CONFIG_NF_TABLES) */
1419 
1420 /*
1421  * We use a free bit in the genmask field to indicate the element
1422  * is busy, meaning it is currently being processed either by
1423  * the netlink API or GC.
1424  *
1425  * Even though the genmask is only a single byte wide, this works
1426  * because the extension structure if fully constant once initialized,
1427  * so there are no non-atomic write accesses unless it is already
1428  * marked busy.
1429  */
1430 #define NFT_SET_ELEM_BUSY_MASK	(1 << 2)
1431 
1432 #if defined(__LITTLE_ENDIAN_BITFIELD)
1433 #define NFT_SET_ELEM_BUSY_BIT	2
1434 #elif defined(__BIG_ENDIAN_BITFIELD)
1435 #define NFT_SET_ELEM_BUSY_BIT	(BITS_PER_LONG - BITS_PER_BYTE + 2)
1436 #else
1437 #error
1438 #endif
1439 
1440 static inline int nft_set_elem_mark_busy(struct nft_set_ext *ext)
1441 {
1442 	unsigned long *word = (unsigned long *)ext;
1443 
1444 	BUILD_BUG_ON(offsetof(struct nft_set_ext, genmask) != 0);
1445 	return test_and_set_bit(NFT_SET_ELEM_BUSY_BIT, word);
1446 }
1447 
1448 static inline void nft_set_elem_clear_busy(struct nft_set_ext *ext)
1449 {
1450 	unsigned long *word = (unsigned long *)ext;
1451 
1452 	clear_bit(NFT_SET_ELEM_BUSY_BIT, word);
1453 }
1454 
1455 /**
1456  *	struct nft_trans - nf_tables object update in transaction
1457  *
1458  *	@list: used internally
1459  *	@msg_type: message type
1460  *	@put_net: ctx->net needs to be put
1461  *	@ctx: transaction context
1462  *	@data: internal information related to the transaction
1463  */
1464 struct nft_trans {
1465 	struct list_head		list;
1466 	int				msg_type;
1467 	bool				put_net;
1468 	struct nft_ctx			ctx;
1469 	char				data[];
1470 };
1471 
1472 struct nft_trans_rule {
1473 	struct nft_rule			*rule;
1474 	struct nft_flow_rule		*flow;
1475 	u32				rule_id;
1476 };
1477 
1478 #define nft_trans_rule(trans)	\
1479 	(((struct nft_trans_rule *)trans->data)->rule)
1480 #define nft_trans_flow_rule(trans)	\
1481 	(((struct nft_trans_rule *)trans->data)->flow)
1482 #define nft_trans_rule_id(trans)	\
1483 	(((struct nft_trans_rule *)trans->data)->rule_id)
1484 
1485 struct nft_trans_set {
1486 	struct nft_set			*set;
1487 	u32				set_id;
1488 	bool				bound;
1489 };
1490 
1491 #define nft_trans_set(trans)	\
1492 	(((struct nft_trans_set *)trans->data)->set)
1493 #define nft_trans_set_id(trans)	\
1494 	(((struct nft_trans_set *)trans->data)->set_id)
1495 #define nft_trans_set_bound(trans)	\
1496 	(((struct nft_trans_set *)trans->data)->bound)
1497 
1498 struct nft_trans_chain {
1499 	bool				update;
1500 	char				*name;
1501 	struct nft_stats __percpu	*stats;
1502 	u8				policy;
1503 	u32				chain_id;
1504 };
1505 
1506 #define nft_trans_chain_update(trans)	\
1507 	(((struct nft_trans_chain *)trans->data)->update)
1508 #define nft_trans_chain_name(trans)	\
1509 	(((struct nft_trans_chain *)trans->data)->name)
1510 #define nft_trans_chain_stats(trans)	\
1511 	(((struct nft_trans_chain *)trans->data)->stats)
1512 #define nft_trans_chain_policy(trans)	\
1513 	(((struct nft_trans_chain *)trans->data)->policy)
1514 #define nft_trans_chain_id(trans)	\
1515 	(((struct nft_trans_chain *)trans->data)->chain_id)
1516 
1517 struct nft_trans_table {
1518 	bool				update;
1519 };
1520 
1521 #define nft_trans_table_update(trans)	\
1522 	(((struct nft_trans_table *)trans->data)->update)
1523 
1524 struct nft_trans_elem {
1525 	struct nft_set			*set;
1526 	struct nft_set_elem		elem;
1527 	bool				bound;
1528 };
1529 
1530 #define nft_trans_elem_set(trans)	\
1531 	(((struct nft_trans_elem *)trans->data)->set)
1532 #define nft_trans_elem(trans)	\
1533 	(((struct nft_trans_elem *)trans->data)->elem)
1534 #define nft_trans_elem_set_bound(trans)	\
1535 	(((struct nft_trans_elem *)trans->data)->bound)
1536 
1537 struct nft_trans_obj {
1538 	struct nft_object		*obj;
1539 	struct nft_object		*newobj;
1540 	bool				update;
1541 };
1542 
1543 #define nft_trans_obj(trans)	\
1544 	(((struct nft_trans_obj *)trans->data)->obj)
1545 #define nft_trans_obj_newobj(trans) \
1546 	(((struct nft_trans_obj *)trans->data)->newobj)
1547 #define nft_trans_obj_update(trans)	\
1548 	(((struct nft_trans_obj *)trans->data)->update)
1549 
1550 struct nft_trans_flowtable {
1551 	struct nft_flowtable		*flowtable;
1552 	bool				update;
1553 	struct list_head		hook_list;
1554 	u32				flags;
1555 };
1556 
1557 #define nft_trans_flowtable(trans)	\
1558 	(((struct nft_trans_flowtable *)trans->data)->flowtable)
1559 #define nft_trans_flowtable_update(trans)	\
1560 	(((struct nft_trans_flowtable *)trans->data)->update)
1561 #define nft_trans_flowtable_hooks(trans)	\
1562 	(((struct nft_trans_flowtable *)trans->data)->hook_list)
1563 #define nft_trans_flowtable_flags(trans)	\
1564 	(((struct nft_trans_flowtable *)trans->data)->flags)
1565 
1566 int __init nft_chain_filter_init(void);
1567 void nft_chain_filter_fini(void);
1568 
1569 void __init nft_chain_route_init(void);
1570 void nft_chain_route_fini(void);
1571 
1572 void nf_tables_trans_destroy_flush_work(void);
1573 
1574 int nf_msecs_to_jiffies64(const struct nlattr *nla, u64 *result);
1575 __be64 nf_jiffies64_to_msecs(u64 input);
1576 
1577 #ifdef CONFIG_MODULES
1578 __printf(2, 3) int nft_request_module(struct net *net, const char *fmt, ...);
1579 #else
1580 static inline int nft_request_module(struct net *net, const char *fmt, ...) { return -ENOENT; }
1581 #endif
1582 
1583 struct nftables_pernet {
1584 	struct list_head	tables;
1585 	struct list_head	commit_list;
1586 	struct list_head	module_list;
1587 	struct list_head	notify_list;
1588 	struct mutex		commit_mutex;
1589 	unsigned int		base_seq;
1590 	u8			validate_state;
1591 };
1592 
1593 extern unsigned int nf_tables_net_id;
1594 
1595 static inline struct nftables_pernet *nft_pernet(const struct net *net)
1596 {
1597 	return net_generic(net, nf_tables_net_id);
1598 }
1599 
1600 #endif /* _NET_NF_TABLES_H */
1601