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
nft_sk(const struct nft_pktinfo * pkt)33 static inline struct sock *nft_sk(const struct nft_pktinfo *pkt)
34 {
35 return pkt->state->sk;
36 }
37
nft_thoff(const struct nft_pktinfo * pkt)38 static inline unsigned int nft_thoff(const struct nft_pktinfo *pkt)
39 {
40 return pkt->thoff;
41 }
42
nft_net(const struct nft_pktinfo * pkt)43 static inline struct net *nft_net(const struct nft_pktinfo *pkt)
44 {
45 return pkt->state->net;
46 }
47
nft_hook(const struct nft_pktinfo * pkt)48 static inline unsigned int nft_hook(const struct nft_pktinfo *pkt)
49 {
50 return pkt->state->hook;
51 }
52
nft_pf(const struct nft_pktinfo * pkt)53 static inline u8 nft_pf(const struct nft_pktinfo *pkt)
54 {
55 return pkt->state->pf;
56 }
57
nft_in(const struct nft_pktinfo * pkt)58 static inline const struct net_device *nft_in(const struct nft_pktinfo *pkt)
59 {
60 return pkt->state->in;
61 }
62
nft_out(const struct nft_pktinfo * pkt)63 static inline const struct net_device *nft_out(const struct nft_pktinfo *pkt)
64 {
65 return pkt->state->out;
66 }
67
nft_set_pktinfo(struct nft_pktinfo * pkt,struct sk_buff * skb,const struct nf_hook_state * state)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
nft_set_pktinfo_unspec(struct nft_pktinfo * pkt)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
nft_reg_store8(u32 * dreg,u8 val)124 static inline void nft_reg_store8(u32 *dreg, u8 val)
125 {
126 *dreg = 0;
127 *(u8 *)dreg = val;
128 }
129
nft_reg_load8(const u32 * sreg)130 static inline u8 nft_reg_load8(const u32 *sreg)
131 {
132 return *(u8 *)sreg;
133 }
134
nft_reg_store16(u32 * dreg,u16 val)135 static inline void nft_reg_store16(u32 *dreg, u16 val)
136 {
137 *dreg = 0;
138 *(u16 *)dreg = val;
139 }
140
nft_reg_load16(const u32 * sreg)141 static inline u16 nft_reg_load16(const u32 *sreg)
142 {
143 return *(u16 *)sreg;
144 }
145
nft_reg_store64(u32 * dreg,u64 val)146 static inline void nft_reg_store64(u32 *dreg, u64 val)
147 {
148 put_unaligned(val, (u64 *)dreg);
149 }
150
nft_reg_load64(const u32 * sreg)151 static inline u64 nft_reg_load64(const u32 *sreg)
152 {
153 return get_unaligned((u64 *)sreg);
154 }
155
nft_data_copy(u32 * dst,const struct nft_data * src,unsigned int len)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
nft_dreg_to_type(enum nft_registers reg)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
nft_type_to_reg(enum nft_data_types type)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
nft_expr_priv(const struct nft_expr * expr)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
nft_set_is_anonymous(const struct nft_set * set)515 static inline bool nft_set_is_anonymous(const struct nft_set *set)
516 {
517 return set->flags & NFT_SET_ANONYMOUS;
518 }
519
nft_set_priv(const struct nft_set * set)520 static inline void *nft_set_priv(const struct nft_set *set)
521 {
522 return (void *)set->data;
523 }
524
nft_set_container_of(const void * priv)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
nft_set_gc_interval(const struct nft_set * set)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
nft_set_ext_prepare(struct nft_set_ext_tmpl * tmpl)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
nft_set_ext_add_length(struct nft_set_ext_tmpl * tmpl,u8 id,unsigned int len)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
nft_set_ext_add(struct nft_set_ext_tmpl * tmpl,u8 id)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
nft_set_ext_init(struct nft_set_ext * ext,const struct nft_set_ext_tmpl * tmpl)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
__nft_set_ext_exists(const struct nft_set_ext * ext,u8 id)659 static inline bool __nft_set_ext_exists(const struct nft_set_ext *ext, u8 id)
660 {
661 return !!ext->offset[id];
662 }
663
nft_set_ext_exists(const struct nft_set_ext * ext,u8 id)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
nft_set_ext(const struct nft_set_ext * ext,u8 id)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
nft_set_ext_key(const struct nft_set_ext * ext)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
nft_set_ext_key_end(const struct nft_set_ext * ext)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
nft_set_ext_data(const struct nft_set_ext * ext)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
nft_set_ext_flags(const struct nft_set_ext * ext)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
nft_set_ext_timeout(const struct nft_set_ext * ext)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
nft_set_ext_expiration(const struct nft_set_ext * ext)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
nft_set_ext_userdata(const struct nft_set_ext * ext)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
nft_set_ext_expr(const struct nft_set_ext * ext)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
nft_set_elem_expired(const struct nft_set_ext * ext)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
nft_set_elem_ext(const struct nft_set * set,void * elem)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
nft_set_ext_obj(const struct nft_set_ext * ext)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
nft_set_gc_batch_complete(struct nft_set_gc_batch * gcb)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 *
nft_set_gc_batch_check(const struct nft_set * set,struct nft_set_gc_batch * gcb,gfp_t gfp)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
nft_set_gc_batch_add(struct nft_set_gc_batch * gcb,void * elem)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
nft_expr_first(const struct nft_rule * rule)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
nft_expr_next(const struct nft_expr * expr)918 static inline struct nft_expr *nft_expr_next(const struct nft_expr *expr)
919 {
920 return ((void *)expr) + expr->ops->size;
921 }
922
nft_expr_last(const struct nft_rule * rule)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
nft_expr_more(const struct nft_rule * rule,const struct nft_expr * expr)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
nft_userdata(const struct nft_rule * rule)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
nft_set_elem_update_expr(const struct nft_set_ext * ext,struct nft_regs * regs,const struct nft_pktinfo * pkt)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
nft_chain_is_bound(struct nft_chain * chain)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
nft_base_chain(const struct nft_chain * chain)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
nft_is_base_chain(const struct nft_chain * chain)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
nft_table_has_owner(const struct nft_table * table)1133 static inline bool nft_table_has_owner(const struct nft_table *table)
1134 {
1135 return table->flags & NFT_TABLE_F_OWNER;
1136 }
1137
nft_base_chain_netdev(int family,u32 hooknum)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
nft_obj_data(const struct nft_object * obj)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, u16 flags, 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 */
nft_gencursor_next(const struct net * net)1357 static inline unsigned int nft_gencursor_next(const struct net *net)
1358 {
1359 return net->nft.gencursor + 1 == 1 ? 1 : 0;
1360 }
1361
nft_genmask_next(const struct net * net)1362 static inline u8 nft_genmask_next(const struct net *net)
1363 {
1364 return 1 << nft_gencursor_next(net);
1365 }
1366
nft_genmask_cur(const struct net * net)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
nft_set_elem_active(const struct nft_set_ext * ext,u8 genmask)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
nft_set_elem_change_active(const struct net * net,const struct nft_set * set,struct nft_set_ext * ext)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
nft_set_elem_mark_busy(struct nft_set_ext * ext)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
nft_set_elem_clear_busy(struct nft_set_ext * ext)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
nft_request_module(struct net * net,const char * fmt,...)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
nft_pernet(const struct net * net)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