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