1 #ifndef _NET_NF_TABLES_H
2 #define _NET_NF_TABLES_H
3
4 #include <linux/list.h>
5 #include <linux/netfilter.h>
6 #include <linux/netfilter/nfnetlink.h>
7 #include <linux/netfilter/x_tables.h>
8 #include <linux/netfilter/nf_tables.h>
9 #include <linux/u64_stats_sync.h>
10 #include <net/netlink.h>
11
12 #define NFT_JUMP_STACK_SIZE 16
13
14 struct nft_pktinfo {
15 struct sk_buff *skb;
16 const struct net_device *in;
17 const struct net_device *out;
18 const struct nf_hook_ops *ops;
19 u8 nhoff;
20 u8 thoff;
21 u8 tprot;
22 /* for x_tables compatibility */
23 struct xt_action_param xt;
24 };
25
nft_set_pktinfo(struct nft_pktinfo * pkt,const struct nf_hook_ops * ops,struct sk_buff * skb,const struct net_device * in,const struct net_device * out)26 static inline void nft_set_pktinfo(struct nft_pktinfo *pkt,
27 const struct nf_hook_ops *ops,
28 struct sk_buff *skb,
29 const struct net_device *in,
30 const struct net_device *out)
31 {
32 pkt->skb = skb;
33 pkt->in = pkt->xt.in = in;
34 pkt->out = pkt->xt.out = out;
35 pkt->ops = ops;
36 pkt->xt.hooknum = ops->hooknum;
37 pkt->xt.family = ops->pf;
38 }
39
40 struct nft_data {
41 union {
42 u32 data[4];
43 struct {
44 u32 verdict;
45 struct nft_chain *chain;
46 };
47 };
48 } __attribute__((aligned(__alignof__(u64))));
49
nft_data_cmp(const struct nft_data * d1,const struct nft_data * d2,unsigned int len)50 static inline int nft_data_cmp(const struct nft_data *d1,
51 const struct nft_data *d2,
52 unsigned int len)
53 {
54 return memcmp(d1->data, d2->data, len);
55 }
56
nft_data_copy(struct nft_data * dst,const struct nft_data * src)57 static inline void nft_data_copy(struct nft_data *dst,
58 const struct nft_data *src)
59 {
60 BUILD_BUG_ON(__alignof__(*dst) != __alignof__(u64));
61 *(u64 *)&dst->data[0] = *(u64 *)&src->data[0];
62 *(u64 *)&dst->data[2] = *(u64 *)&src->data[2];
63 }
64
nft_data_debug(const struct nft_data * data)65 static inline void nft_data_debug(const struct nft_data *data)
66 {
67 pr_debug("data[0]=%x data[1]=%x data[2]=%x data[3]=%x\n",
68 data->data[0], data->data[1],
69 data->data[2], data->data[3]);
70 }
71
72 /**
73 * struct nft_ctx - nf_tables rule/set context
74 *
75 * @net: net namespace
76 * @afi: address family info
77 * @table: the table the chain is contained in
78 * @chain: the chain the rule is contained in
79 * @nla: netlink attributes
80 * @portid: netlink portID of the original message
81 * @seq: netlink sequence number
82 * @report: notify via unicast netlink message
83 */
84 struct nft_ctx {
85 struct net *net;
86 struct nft_af_info *afi;
87 struct nft_table *table;
88 struct nft_chain *chain;
89 const struct nlattr * const *nla;
90 u32 portid;
91 u32 seq;
92 bool report;
93 };
94
95 struct nft_data_desc {
96 enum nft_data_types type;
97 unsigned int len;
98 };
99
100 int nft_data_init(const struct nft_ctx *ctx, struct nft_data *data,
101 struct nft_data_desc *desc, const struct nlattr *nla);
102 void nft_data_uninit(const struct nft_data *data, enum nft_data_types type);
103 int nft_data_dump(struct sk_buff *skb, int attr, const struct nft_data *data,
104 enum nft_data_types type, unsigned int len);
105
nft_dreg_to_type(enum nft_registers reg)106 static inline enum nft_data_types nft_dreg_to_type(enum nft_registers reg)
107 {
108 return reg == NFT_REG_VERDICT ? NFT_DATA_VERDICT : NFT_DATA_VALUE;
109 }
110
nft_type_to_reg(enum nft_data_types type)111 static inline enum nft_registers nft_type_to_reg(enum nft_data_types type)
112 {
113 return type == NFT_DATA_VERDICT ? NFT_REG_VERDICT : NFT_REG_1;
114 }
115
116 int nft_validate_input_register(enum nft_registers reg);
117 int nft_validate_output_register(enum nft_registers reg);
118 int nft_validate_data_load(const struct nft_ctx *ctx, enum nft_registers reg,
119 const struct nft_data *data,
120 enum nft_data_types type);
121
122 /**
123 * struct nft_set_elem - generic representation of set elements
124 *
125 * @cookie: implementation specific element cookie
126 * @key: element key
127 * @data: element data (maps only)
128 * @flags: element flags (end of interval)
129 *
130 * The cookie can be used to store a handle to the element for subsequent
131 * removal.
132 */
133 struct nft_set_elem {
134 void *cookie;
135 struct nft_data key;
136 struct nft_data data;
137 u32 flags;
138 };
139
140 struct nft_set;
141 struct nft_set_iter {
142 unsigned int count;
143 unsigned int skip;
144 int err;
145 int (*fn)(const struct nft_ctx *ctx,
146 const struct nft_set *set,
147 const struct nft_set_iter *iter,
148 const struct nft_set_elem *elem);
149 };
150
151 /**
152 * struct nft_set_desc - description of set elements
153 *
154 * @klen: key length
155 * @dlen: data length
156 * @size: number of set elements
157 */
158 struct nft_set_desc {
159 unsigned int klen;
160 unsigned int dlen;
161 unsigned int size;
162 };
163
164 /**
165 * enum nft_set_class - performance class
166 *
167 * @NFT_LOOKUP_O_1: constant, O(1)
168 * @NFT_LOOKUP_O_LOG_N: logarithmic, O(log N)
169 * @NFT_LOOKUP_O_N: linear, O(N)
170 */
171 enum nft_set_class {
172 NFT_SET_CLASS_O_1,
173 NFT_SET_CLASS_O_LOG_N,
174 NFT_SET_CLASS_O_N,
175 };
176
177 /**
178 * struct nft_set_estimate - estimation of memory and performance
179 * characteristics
180 *
181 * @size: required memory
182 * @class: lookup performance class
183 */
184 struct nft_set_estimate {
185 unsigned int size;
186 enum nft_set_class class;
187 };
188
189 /**
190 * struct nft_set_ops - nf_tables set operations
191 *
192 * @lookup: look up an element within the set
193 * @insert: insert new element into set
194 * @remove: remove element from set
195 * @walk: iterate over all set elemeennts
196 * @privsize: function to return size of set private data
197 * @init: initialize private data of new set instance
198 * @destroy: destroy private data of set instance
199 * @list: nf_tables_set_ops list node
200 * @owner: module reference
201 * @features: features supported by the implementation
202 */
203 struct nft_set_ops {
204 bool (*lookup)(const struct nft_set *set,
205 const struct nft_data *key,
206 struct nft_data *data);
207 int (*get)(const struct nft_set *set,
208 struct nft_set_elem *elem);
209 int (*insert)(const struct nft_set *set,
210 const struct nft_set_elem *elem);
211 void (*remove)(const struct nft_set *set,
212 const struct nft_set_elem *elem);
213 void (*walk)(const struct nft_ctx *ctx,
214 const struct nft_set *set,
215 struct nft_set_iter *iter);
216
217 unsigned int (*privsize)(const struct nlattr * const nla[]);
218 bool (*estimate)(const struct nft_set_desc *desc,
219 u32 features,
220 struct nft_set_estimate *est);
221 int (*init)(const struct nft_set *set,
222 const struct nft_set_desc *desc,
223 const struct nlattr * const nla[]);
224 void (*destroy)(const struct nft_set *set);
225
226 struct list_head list;
227 struct module *owner;
228 u32 features;
229 };
230
231 int nft_register_set(struct nft_set_ops *ops);
232 void nft_unregister_set(struct nft_set_ops *ops);
233
234 /**
235 * struct nft_set - nf_tables set instance
236 *
237 * @list: table set list node
238 * @bindings: list of set bindings
239 * @name: name of the set
240 * @ktype: key type (numeric type defined by userspace, not used in the kernel)
241 * @dtype: data type (verdict or numeric type defined by userspace)
242 * @size: maximum set size
243 * @nelems: number of elements
244 * @policy: set parameterization (see enum nft_set_policies)
245 * @ops: set ops
246 * @flags: set flags
247 * @klen: key length
248 * @dlen: data length
249 * @data: private set data
250 */
251 struct nft_set {
252 struct list_head list;
253 struct list_head bindings;
254 char name[IFNAMSIZ];
255 u32 ktype;
256 u32 dtype;
257 u32 size;
258 u32 nelems;
259 u16 policy;
260 /* runtime data below here */
261 const struct nft_set_ops *ops ____cacheline_aligned;
262 u16 flags;
263 u8 klen;
264 u8 dlen;
265 unsigned char data[]
266 __attribute__((aligned(__alignof__(u64))));
267 };
268
nft_set_priv(const struct nft_set * set)269 static inline void *nft_set_priv(const struct nft_set *set)
270 {
271 return (void *)set->data;
272 }
273
274 struct nft_set *nf_tables_set_lookup(const struct nft_table *table,
275 const struct nlattr *nla);
276 struct nft_set *nf_tables_set_lookup_byid(const struct net *net,
277 const struct nlattr *nla);
278
279 /**
280 * struct nft_set_binding - nf_tables set binding
281 *
282 * @list: set bindings list node
283 * @chain: chain containing the rule bound to the set
284 *
285 * A set binding contains all information necessary for validation
286 * of new elements added to a bound set.
287 */
288 struct nft_set_binding {
289 struct list_head list;
290 const struct nft_chain *chain;
291 };
292
293 int nf_tables_bind_set(const struct nft_ctx *ctx, struct nft_set *set,
294 struct nft_set_binding *binding);
295 void nf_tables_unbind_set(const struct nft_ctx *ctx, struct nft_set *set,
296 struct nft_set_binding *binding);
297
298
299 /**
300 * struct nft_expr_type - nf_tables expression type
301 *
302 * @select_ops: function to select nft_expr_ops
303 * @ops: default ops, used when no select_ops functions is present
304 * @list: used internally
305 * @name: Identifier
306 * @owner: module reference
307 * @policy: netlink attribute policy
308 * @maxattr: highest netlink attribute number
309 * @family: address family for AF-specific types
310 */
311 struct nft_expr_type {
312 const struct nft_expr_ops *(*select_ops)(const struct nft_ctx *,
313 const struct nlattr * const tb[]);
314 const struct nft_expr_ops *ops;
315 struct list_head list;
316 const char *name;
317 struct module *owner;
318 const struct nla_policy *policy;
319 unsigned int maxattr;
320 u8 family;
321 };
322
323 /**
324 * struct nft_expr_ops - nf_tables expression operations
325 *
326 * @eval: Expression evaluation function
327 * @size: full expression size, including private data size
328 * @init: initialization function
329 * @destroy: destruction function
330 * @dump: function to dump parameters
331 * @type: expression type
332 * @validate: validate expression, called during loop detection
333 * @data: extra data to attach to this expression operation
334 */
335 struct nft_expr;
336 struct nft_expr_ops {
337 void (*eval)(const struct nft_expr *expr,
338 struct nft_data data[NFT_REG_MAX + 1],
339 const struct nft_pktinfo *pkt);
340 unsigned int size;
341
342 int (*init)(const struct nft_ctx *ctx,
343 const struct nft_expr *expr,
344 const struct nlattr * const tb[]);
345 void (*destroy)(const struct nft_ctx *ctx,
346 const struct nft_expr *expr);
347 int (*dump)(struct sk_buff *skb,
348 const struct nft_expr *expr);
349 int (*validate)(const struct nft_ctx *ctx,
350 const struct nft_expr *expr,
351 const struct nft_data **data);
352 const struct nft_expr_type *type;
353 void *data;
354 };
355
356 #define NFT_EXPR_MAXATTR 16
357 #define NFT_EXPR_SIZE(size) (sizeof(struct nft_expr) + \
358 ALIGN(size, __alignof__(struct nft_expr)))
359
360 /**
361 * struct nft_expr - nf_tables expression
362 *
363 * @ops: expression ops
364 * @data: expression private data
365 */
366 struct nft_expr {
367 const struct nft_expr_ops *ops;
368 unsigned char data[];
369 };
370
nft_expr_priv(const struct nft_expr * expr)371 static inline void *nft_expr_priv(const struct nft_expr *expr)
372 {
373 return (void *)expr->data;
374 }
375
376 /**
377 * struct nft_rule - nf_tables rule
378 *
379 * @list: used internally
380 * @handle: rule handle
381 * @genmask: generation mask
382 * @dlen: length of expression data
383 * @ulen: length of user data (used for comments)
384 * @data: expression data
385 */
386 struct nft_rule {
387 struct list_head list;
388 u64 handle:42,
389 genmask:2,
390 dlen:12,
391 ulen:8;
392 unsigned char data[]
393 __attribute__((aligned(__alignof__(struct nft_expr))));
394 };
395
396 /**
397 * struct nft_trans - nf_tables object update in transaction
398 *
399 * @list: used internally
400 * @msg_type: message type
401 * @ctx: transaction context
402 * @data: internal information related to the transaction
403 */
404 struct nft_trans {
405 struct list_head list;
406 int msg_type;
407 struct nft_ctx ctx;
408 char data[0];
409 };
410
411 struct nft_trans_rule {
412 struct nft_rule *rule;
413 };
414
415 #define nft_trans_rule(trans) \
416 (((struct nft_trans_rule *)trans->data)->rule)
417
418 struct nft_trans_set {
419 struct nft_set *set;
420 u32 set_id;
421 };
422
423 #define nft_trans_set(trans) \
424 (((struct nft_trans_set *)trans->data)->set)
425 #define nft_trans_set_id(trans) \
426 (((struct nft_trans_set *)trans->data)->set_id)
427
428 struct nft_trans_chain {
429 bool update;
430 char name[NFT_CHAIN_MAXNAMELEN];
431 struct nft_stats __percpu *stats;
432 u8 policy;
433 };
434
435 #define nft_trans_chain_update(trans) \
436 (((struct nft_trans_chain *)trans->data)->update)
437 #define nft_trans_chain_name(trans) \
438 (((struct nft_trans_chain *)trans->data)->name)
439 #define nft_trans_chain_stats(trans) \
440 (((struct nft_trans_chain *)trans->data)->stats)
441 #define nft_trans_chain_policy(trans) \
442 (((struct nft_trans_chain *)trans->data)->policy)
443
444 struct nft_trans_table {
445 bool update;
446 bool enable;
447 };
448
449 #define nft_trans_table_update(trans) \
450 (((struct nft_trans_table *)trans->data)->update)
451 #define nft_trans_table_enable(trans) \
452 (((struct nft_trans_table *)trans->data)->enable)
453
454 struct nft_trans_elem {
455 struct nft_set *set;
456 struct nft_set_elem elem;
457 };
458
459 #define nft_trans_elem_set(trans) \
460 (((struct nft_trans_elem *)trans->data)->set)
461 #define nft_trans_elem(trans) \
462 (((struct nft_trans_elem *)trans->data)->elem)
463
nft_expr_first(const struct nft_rule * rule)464 static inline struct nft_expr *nft_expr_first(const struct nft_rule *rule)
465 {
466 return (struct nft_expr *)&rule->data[0];
467 }
468
nft_expr_next(const struct nft_expr * expr)469 static inline struct nft_expr *nft_expr_next(const struct nft_expr *expr)
470 {
471 return ((void *)expr) + expr->ops->size;
472 }
473
nft_expr_last(const struct nft_rule * rule)474 static inline struct nft_expr *nft_expr_last(const struct nft_rule *rule)
475 {
476 return (struct nft_expr *)&rule->data[rule->dlen];
477 }
478
nft_userdata(const struct nft_rule * rule)479 static inline void *nft_userdata(const struct nft_rule *rule)
480 {
481 return (void *)&rule->data[rule->dlen];
482 }
483
484 /*
485 * The last pointer isn't really necessary, but the compiler isn't able to
486 * determine that the result of nft_expr_last() is always the same since it
487 * can't assume that the dlen value wasn't changed within calls in the loop.
488 */
489 #define nft_rule_for_each_expr(expr, last, rule) \
490 for ((expr) = nft_expr_first(rule), (last) = nft_expr_last(rule); \
491 (expr) != (last); \
492 (expr) = nft_expr_next(expr))
493
494 enum nft_chain_flags {
495 NFT_BASE_CHAIN = 0x1,
496 NFT_CHAIN_INACTIVE = 0x2,
497 };
498
499 /**
500 * struct nft_chain - nf_tables chain
501 *
502 * @rules: list of rules in the chain
503 * @list: used internally
504 * @net: net namespace that this chain belongs to
505 * @table: table that this chain belongs to
506 * @handle: chain handle
507 * @use: number of jump references to this chain
508 * @level: length of longest path to this chain
509 * @flags: bitmask of enum nft_chain_flags
510 * @name: name of the chain
511 */
512 struct nft_chain {
513 struct list_head rules;
514 struct list_head list;
515 struct net *net;
516 struct nft_table *table;
517 u64 handle;
518 u32 use;
519 u16 level;
520 u8 flags;
521 char name[NFT_CHAIN_MAXNAMELEN];
522 };
523
524 enum nft_chain_type {
525 NFT_CHAIN_T_DEFAULT = 0,
526 NFT_CHAIN_T_ROUTE,
527 NFT_CHAIN_T_NAT,
528 NFT_CHAIN_T_MAX
529 };
530
531 int nft_chain_validate_dependency(const struct nft_chain *chain,
532 enum nft_chain_type type);
533
534 struct nft_stats {
535 u64 bytes;
536 u64 pkts;
537 struct u64_stats_sync syncp;
538 };
539
540 #define NFT_HOOK_OPS_MAX 2
541
542 /**
543 * struct nft_base_chain - nf_tables base chain
544 *
545 * @ops: netfilter hook ops
546 * @type: chain type
547 * @policy: default policy
548 * @stats: per-cpu chain stats
549 * @chain: the chain
550 */
551 struct nft_base_chain {
552 struct nf_hook_ops ops[NFT_HOOK_OPS_MAX];
553 const struct nf_chain_type *type;
554 u8 policy;
555 struct nft_stats __percpu *stats;
556 struct nft_chain chain;
557 };
558
nft_base_chain(const struct nft_chain * chain)559 static inline struct nft_base_chain *nft_base_chain(const struct nft_chain *chain)
560 {
561 return container_of(chain, struct nft_base_chain, chain);
562 }
563
564 unsigned int nft_do_chain(struct nft_pktinfo *pkt,
565 const struct nf_hook_ops *ops);
566
567 /**
568 * struct nft_table - nf_tables table
569 *
570 * @list: used internally
571 * @chains: chains in the table
572 * @sets: sets in the table
573 * @hgenerator: handle generator state
574 * @use: number of chain references to this table
575 * @flags: table flag (see enum nft_table_flags)
576 * @name: name of the table
577 */
578 struct nft_table {
579 struct list_head list;
580 struct list_head chains;
581 struct list_head sets;
582 u64 hgenerator;
583 u32 use;
584 u16 flags;
585 char name[];
586 };
587
588 /**
589 * struct nft_af_info - nf_tables address family info
590 *
591 * @list: used internally
592 * @family: address family
593 * @nhooks: number of hooks in this family
594 * @owner: module owner
595 * @tables: used internally
596 * @nops: number of hook ops in this family
597 * @hook_ops_init: initialization function for chain hook ops
598 * @hooks: hookfn overrides for packet validation
599 */
600 struct nft_af_info {
601 struct list_head list;
602 int family;
603 unsigned int nhooks;
604 struct module *owner;
605 struct list_head tables;
606 unsigned int nops;
607 void (*hook_ops_init)(struct nf_hook_ops *,
608 unsigned int);
609 nf_hookfn *hooks[NF_MAX_HOOKS];
610 };
611
612 int nft_register_afinfo(struct net *, struct nft_af_info *);
613 void nft_unregister_afinfo(struct nft_af_info *);
614
615 /**
616 * struct nf_chain_type - nf_tables chain type info
617 *
618 * @name: name of the type
619 * @type: numeric identifier
620 * @family: address family
621 * @owner: module owner
622 * @hook_mask: mask of valid hooks
623 * @hooks: hookfn overrides
624 */
625 struct nf_chain_type {
626 const char *name;
627 enum nft_chain_type type;
628 int family;
629 struct module *owner;
630 unsigned int hook_mask;
631 nf_hookfn *hooks[NF_MAX_HOOKS];
632 };
633
634 int nft_register_chain_type(const struct nf_chain_type *);
635 void nft_unregister_chain_type(const struct nf_chain_type *);
636
637 int nft_register_expr(struct nft_expr_type *);
638 void nft_unregister_expr(struct nft_expr_type *);
639
640 #define nft_dereference(p) \
641 nfnl_dereference(p, NFNL_SUBSYS_NFTABLES)
642
643 #define MODULE_ALIAS_NFT_FAMILY(family) \
644 MODULE_ALIAS("nft-afinfo-" __stringify(family))
645
646 #define MODULE_ALIAS_NFT_CHAIN(family, name) \
647 MODULE_ALIAS("nft-chain-" __stringify(family) "-" name)
648
649 #define MODULE_ALIAS_NFT_AF_EXPR(family, name) \
650 MODULE_ALIAS("nft-expr-" __stringify(family) "-" name)
651
652 #define MODULE_ALIAS_NFT_EXPR(name) \
653 MODULE_ALIAS("nft-expr-" name)
654
655 #define MODULE_ALIAS_NFT_SET() \
656 MODULE_ALIAS("nft-set")
657
658 #endif /* _NET_NF_TABLES_H */
659