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8#include <linux/kernel.h>
9#include <linux/init.h>
10#include <linux/module.h>
11#include <linux/netlink.h>
12#include <linux/netfilter.h>
13#include <linux/netfilter/nfnetlink.h>
14#include <linux/netfilter/nf_tables.h>
15#include <linux/netfilter/nf_tables_compat.h>
16#include <linux/netfilter/x_tables.h>
17#include <linux/netfilter_ipv4/ip_tables.h>
18#include <linux/netfilter_ipv6/ip6_tables.h>
19#include <linux/netfilter_bridge/ebtables.h>
20#include <linux/netfilter_arp/arp_tables.h>
21#include <net/netfilter/nf_tables.h>
22
23
24#define NFT_MATCH_LARGE_THRESH 192
25
26struct nft_xt_match_priv {
27 void *info;
28};
29
30static int nft_compat_chain_validate_dependency(const struct nft_ctx *ctx,
31 const char *tablename)
32{
33 enum nft_chain_types type = NFT_CHAIN_T_DEFAULT;
34 const struct nft_chain *chain = ctx->chain;
35 const struct nft_base_chain *basechain;
36
37 if (!tablename ||
38 !nft_is_base_chain(chain))
39 return 0;
40
41 basechain = nft_base_chain(chain);
42 if (strcmp(tablename, "nat") == 0) {
43 if (ctx->family != NFPROTO_BRIDGE)
44 type = NFT_CHAIN_T_NAT;
45 if (basechain->type->type != type)
46 return -EINVAL;
47 }
48
49 return 0;
50}
51
52union nft_entry {
53 struct ipt_entry e4;
54 struct ip6t_entry e6;
55 struct ebt_entry ebt;
56 struct arpt_entry arp;
57};
58
59static inline void
60nft_compat_set_par(struct xt_action_param *par,
61 const struct nft_pktinfo *pkt,
62 const void *xt, const void *xt_info)
63{
64 par->state = pkt->state;
65 par->thoff = nft_thoff(pkt);
66 par->fragoff = pkt->fragoff;
67 par->target = xt;
68 par->targinfo = xt_info;
69 par->hotdrop = false;
70}
71
72static void nft_target_eval_xt(const struct nft_expr *expr,
73 struct nft_regs *regs,
74 const struct nft_pktinfo *pkt)
75{
76 void *info = nft_expr_priv(expr);
77 struct xt_target *target = expr->ops->data;
78 struct sk_buff *skb = pkt->skb;
79 struct xt_action_param xt;
80 int ret;
81
82 nft_compat_set_par(&xt, pkt, target, info);
83
84 ret = target->target(skb, &xt);
85
86 if (xt.hotdrop)
87 ret = NF_DROP;
88
89 switch (ret) {
90 case XT_CONTINUE:
91 regs->verdict.code = NFT_CONTINUE;
92 break;
93 default:
94 regs->verdict.code = ret;
95 break;
96 }
97}
98
99static void nft_target_eval_bridge(const struct nft_expr *expr,
100 struct nft_regs *regs,
101 const struct nft_pktinfo *pkt)
102{
103 void *info = nft_expr_priv(expr);
104 struct xt_target *target = expr->ops->data;
105 struct sk_buff *skb = pkt->skb;
106 struct xt_action_param xt;
107 int ret;
108
109 nft_compat_set_par(&xt, pkt, target, info);
110
111 ret = target->target(skb, &xt);
112
113 if (xt.hotdrop)
114 ret = NF_DROP;
115
116 switch (ret) {
117 case EBT_ACCEPT:
118 regs->verdict.code = NF_ACCEPT;
119 break;
120 case EBT_DROP:
121 regs->verdict.code = NF_DROP;
122 break;
123 case EBT_CONTINUE:
124 regs->verdict.code = NFT_CONTINUE;
125 break;
126 case EBT_RETURN:
127 regs->verdict.code = NFT_RETURN;
128 break;
129 default:
130 regs->verdict.code = ret;
131 break;
132 }
133}
134
135static const struct nla_policy nft_target_policy[NFTA_TARGET_MAX + 1] = {
136 [NFTA_TARGET_NAME] = { .type = NLA_NUL_STRING },
137 [NFTA_TARGET_REV] = { .type = NLA_U32 },
138 [NFTA_TARGET_INFO] = { .type = NLA_BINARY },
139};
140
141static void
142nft_target_set_tgchk_param(struct xt_tgchk_param *par,
143 const struct nft_ctx *ctx,
144 struct xt_target *target, void *info,
145 union nft_entry *entry, u16 proto, bool inv)
146{
147 par->net = ctx->net;
148 par->table = ctx->table->name;
149 switch (ctx->family) {
150 case AF_INET:
151 entry->e4.ip.proto = proto;
152 entry->e4.ip.invflags = inv ? IPT_INV_PROTO : 0;
153 break;
154 case AF_INET6:
155 if (proto)
156 entry->e6.ipv6.flags |= IP6T_F_PROTO;
157
158 entry->e6.ipv6.proto = proto;
159 entry->e6.ipv6.invflags = inv ? IP6T_INV_PROTO : 0;
160 break;
161 case NFPROTO_BRIDGE:
162 entry->ebt.ethproto = (__force __be16)proto;
163 entry->ebt.invflags = inv ? EBT_IPROTO : 0;
164 break;
165 case NFPROTO_ARP:
166 break;
167 }
168 par->entryinfo = entry;
169 par->target = target;
170 par->targinfo = info;
171 if (nft_is_base_chain(ctx->chain)) {
172 const struct nft_base_chain *basechain =
173 nft_base_chain(ctx->chain);
174 const struct nf_hook_ops *ops = &basechain->ops;
175
176 par->hook_mask = 1 << ops->hooknum;
177 } else {
178 par->hook_mask = 0;
179 }
180 par->family = ctx->family;
181 par->nft_compat = true;
182}
183
184static void target_compat_from_user(struct xt_target *t, void *in, void *out)
185{
186 int pad;
187
188 memcpy(out, in, t->targetsize);
189 pad = XT_ALIGN(t->targetsize) - t->targetsize;
190 if (pad > 0)
191 memset(out + t->targetsize, 0, pad);
192}
193
194static const struct nla_policy nft_rule_compat_policy[NFTA_RULE_COMPAT_MAX + 1] = {
195 [NFTA_RULE_COMPAT_PROTO] = { .type = NLA_U32 },
196 [NFTA_RULE_COMPAT_FLAGS] = { .type = NLA_U32 },
197};
198
199static int nft_parse_compat(const struct nlattr *attr, u16 *proto, bool *inv)
200{
201 struct nlattr *tb[NFTA_RULE_COMPAT_MAX+1];
202 u32 flags;
203 int err;
204
205 err = nla_parse_nested_deprecated(tb, NFTA_RULE_COMPAT_MAX, attr,
206 nft_rule_compat_policy, NULL);
207 if (err < 0)
208 return err;
209
210 if (!tb[NFTA_RULE_COMPAT_PROTO] || !tb[NFTA_RULE_COMPAT_FLAGS])
211 return -EINVAL;
212
213 flags = ntohl(nla_get_be32(tb[NFTA_RULE_COMPAT_FLAGS]));
214 if (flags & ~NFT_RULE_COMPAT_F_MASK)
215 return -EINVAL;
216 if (flags & NFT_RULE_COMPAT_F_INV)
217 *inv = true;
218
219 *proto = ntohl(nla_get_be32(tb[NFTA_RULE_COMPAT_PROTO]));
220 return 0;
221}
222
223static void nft_compat_wait_for_destructors(void)
224{
225
226
227
228
229
230
231 nf_tables_trans_destroy_flush_work();
232}
233
234static int
235nft_target_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
236 const struct nlattr * const tb[])
237{
238 void *info = nft_expr_priv(expr);
239 struct xt_target *target = expr->ops->data;
240 struct xt_tgchk_param par;
241 size_t size = XT_ALIGN(nla_len(tb[NFTA_TARGET_INFO]));
242 u16 proto = 0;
243 bool inv = false;
244 union nft_entry e = {};
245 int ret;
246
247 target_compat_from_user(target, nla_data(tb[NFTA_TARGET_INFO]), info);
248
249 if (ctx->nla[NFTA_RULE_COMPAT]) {
250 ret = nft_parse_compat(ctx->nla[NFTA_RULE_COMPAT], &proto, &inv);
251 if (ret < 0)
252 return ret;
253 }
254
255 nft_target_set_tgchk_param(&par, ctx, target, info, &e, proto, inv);
256
257 nft_compat_wait_for_destructors();
258
259 ret = xt_check_target(&par, size, proto, inv);
260 if (ret < 0)
261 return ret;
262
263
264 if (!target->target)
265 return -EINVAL;
266
267 return 0;
268}
269
270static void __nft_mt_tg_destroy(struct module *me, const struct nft_expr *expr)
271{
272 module_put(me);
273 kfree(expr->ops);
274}
275
276static void
277nft_target_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr)
278{
279 struct xt_target *target = expr->ops->data;
280 void *info = nft_expr_priv(expr);
281 struct module *me = target->me;
282 struct xt_tgdtor_param par;
283
284 par.net = ctx->net;
285 par.target = target;
286 par.targinfo = info;
287 par.family = ctx->family;
288 if (par.target->destroy != NULL)
289 par.target->destroy(&par);
290
291 __nft_mt_tg_destroy(me, expr);
292}
293
294static int nft_extension_dump_info(struct sk_buff *skb, int attr,
295 const void *info,
296 unsigned int size, unsigned int user_size)
297{
298 unsigned int info_size, aligned_size = XT_ALIGN(size);
299 struct nlattr *nla;
300
301 nla = nla_reserve(skb, attr, aligned_size);
302 if (!nla)
303 return -1;
304
305 info_size = user_size ? : size;
306 memcpy(nla_data(nla), info, info_size);
307 memset(nla_data(nla) + info_size, 0, aligned_size - info_size);
308
309 return 0;
310}
311
312static int nft_target_dump(struct sk_buff *skb, const struct nft_expr *expr)
313{
314 const struct xt_target *target = expr->ops->data;
315 void *info = nft_expr_priv(expr);
316
317 if (nla_put_string(skb, NFTA_TARGET_NAME, target->name) ||
318 nla_put_be32(skb, NFTA_TARGET_REV, htonl(target->revision)) ||
319 nft_extension_dump_info(skb, NFTA_TARGET_INFO, info,
320 target->targetsize, target->usersize))
321 goto nla_put_failure;
322
323 return 0;
324
325nla_put_failure:
326 return -1;
327}
328
329static int nft_target_validate(const struct nft_ctx *ctx,
330 const struct nft_expr *expr,
331 const struct nft_data **data)
332{
333 struct xt_target *target = expr->ops->data;
334 unsigned int hook_mask = 0;
335 int ret;
336
337 if (nft_is_base_chain(ctx->chain)) {
338 const struct nft_base_chain *basechain =
339 nft_base_chain(ctx->chain);
340 const struct nf_hook_ops *ops = &basechain->ops;
341
342 hook_mask = 1 << ops->hooknum;
343 if (target->hooks && !(hook_mask & target->hooks))
344 return -EINVAL;
345
346 ret = nft_compat_chain_validate_dependency(ctx, target->table);
347 if (ret < 0)
348 return ret;
349 }
350 return 0;
351}
352
353static void __nft_match_eval(const struct nft_expr *expr,
354 struct nft_regs *regs,
355 const struct nft_pktinfo *pkt,
356 void *info)
357{
358 struct xt_match *match = expr->ops->data;
359 struct sk_buff *skb = pkt->skb;
360 struct xt_action_param xt;
361 bool ret;
362
363 nft_compat_set_par(&xt, pkt, match, info);
364
365 ret = match->match(skb, &xt);
366
367 if (xt.hotdrop) {
368 regs->verdict.code = NF_DROP;
369 return;
370 }
371
372 switch (ret ? 1 : 0) {
373 case 1:
374 regs->verdict.code = NFT_CONTINUE;
375 break;
376 case 0:
377 regs->verdict.code = NFT_BREAK;
378 break;
379 }
380}
381
382static void nft_match_large_eval(const struct nft_expr *expr,
383 struct nft_regs *regs,
384 const struct nft_pktinfo *pkt)
385{
386 struct nft_xt_match_priv *priv = nft_expr_priv(expr);
387
388 __nft_match_eval(expr, regs, pkt, priv->info);
389}
390
391static void nft_match_eval(const struct nft_expr *expr,
392 struct nft_regs *regs,
393 const struct nft_pktinfo *pkt)
394{
395 __nft_match_eval(expr, regs, pkt, nft_expr_priv(expr));
396}
397
398static const struct nla_policy nft_match_policy[NFTA_MATCH_MAX + 1] = {
399 [NFTA_MATCH_NAME] = { .type = NLA_NUL_STRING },
400 [NFTA_MATCH_REV] = { .type = NLA_U32 },
401 [NFTA_MATCH_INFO] = { .type = NLA_BINARY },
402};
403
404
405static void
406nft_match_set_mtchk_param(struct xt_mtchk_param *par, const struct nft_ctx *ctx,
407 struct xt_match *match, void *info,
408 union nft_entry *entry, u16 proto, bool inv)
409{
410 par->net = ctx->net;
411 par->table = ctx->table->name;
412 switch (ctx->family) {
413 case AF_INET:
414 entry->e4.ip.proto = proto;
415 entry->e4.ip.invflags = inv ? IPT_INV_PROTO : 0;
416 break;
417 case AF_INET6:
418 if (proto)
419 entry->e6.ipv6.flags |= IP6T_F_PROTO;
420
421 entry->e6.ipv6.proto = proto;
422 entry->e6.ipv6.invflags = inv ? IP6T_INV_PROTO : 0;
423 break;
424 case NFPROTO_BRIDGE:
425 entry->ebt.ethproto = (__force __be16)proto;
426 entry->ebt.invflags = inv ? EBT_IPROTO : 0;
427 break;
428 case NFPROTO_ARP:
429 break;
430 }
431 par->entryinfo = entry;
432 par->match = match;
433 par->matchinfo = info;
434 if (nft_is_base_chain(ctx->chain)) {
435 const struct nft_base_chain *basechain =
436 nft_base_chain(ctx->chain);
437 const struct nf_hook_ops *ops = &basechain->ops;
438
439 par->hook_mask = 1 << ops->hooknum;
440 } else {
441 par->hook_mask = 0;
442 }
443 par->family = ctx->family;
444 par->nft_compat = true;
445}
446
447static void match_compat_from_user(struct xt_match *m, void *in, void *out)
448{
449 int pad;
450
451 memcpy(out, in, m->matchsize);
452 pad = XT_ALIGN(m->matchsize) - m->matchsize;
453 if (pad > 0)
454 memset(out + m->matchsize, 0, pad);
455}
456
457static int
458__nft_match_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
459 const struct nlattr * const tb[],
460 void *info)
461{
462 struct xt_match *match = expr->ops->data;
463 struct xt_mtchk_param par;
464 size_t size = XT_ALIGN(nla_len(tb[NFTA_MATCH_INFO]));
465 u16 proto = 0;
466 bool inv = false;
467 union nft_entry e = {};
468 int ret;
469
470 match_compat_from_user(match, nla_data(tb[NFTA_MATCH_INFO]), info);
471
472 if (ctx->nla[NFTA_RULE_COMPAT]) {
473 ret = nft_parse_compat(ctx->nla[NFTA_RULE_COMPAT], &proto, &inv);
474 if (ret < 0)
475 return ret;
476 }
477
478 nft_match_set_mtchk_param(&par, ctx, match, info, &e, proto, inv);
479
480 nft_compat_wait_for_destructors();
481
482 return xt_check_match(&par, size, proto, inv);
483}
484
485static int
486nft_match_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
487 const struct nlattr * const tb[])
488{
489 return __nft_match_init(ctx, expr, tb, nft_expr_priv(expr));
490}
491
492static int
493nft_match_large_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
494 const struct nlattr * const tb[])
495{
496 struct nft_xt_match_priv *priv = nft_expr_priv(expr);
497 struct xt_match *m = expr->ops->data;
498 int ret;
499
500 priv->info = kmalloc(XT_ALIGN(m->matchsize), GFP_KERNEL);
501 if (!priv->info)
502 return -ENOMEM;
503
504 ret = __nft_match_init(ctx, expr, tb, priv->info);
505 if (ret)
506 kfree(priv->info);
507 return ret;
508}
509
510static void
511__nft_match_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr,
512 void *info)
513{
514 struct xt_match *match = expr->ops->data;
515 struct module *me = match->me;
516 struct xt_mtdtor_param par;
517
518 par.net = ctx->net;
519 par.match = match;
520 par.matchinfo = info;
521 par.family = ctx->family;
522 if (par.match->destroy != NULL)
523 par.match->destroy(&par);
524
525 __nft_mt_tg_destroy(me, expr);
526}
527
528static void
529nft_match_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr)
530{
531 __nft_match_destroy(ctx, expr, nft_expr_priv(expr));
532}
533
534static void
535nft_match_large_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr)
536{
537 struct nft_xt_match_priv *priv = nft_expr_priv(expr);
538
539 __nft_match_destroy(ctx, expr, priv->info);
540 kfree(priv->info);
541}
542
543static int __nft_match_dump(struct sk_buff *skb, const struct nft_expr *expr,
544 void *info)
545{
546 struct xt_match *match = expr->ops->data;
547
548 if (nla_put_string(skb, NFTA_MATCH_NAME, match->name) ||
549 nla_put_be32(skb, NFTA_MATCH_REV, htonl(match->revision)) ||
550 nft_extension_dump_info(skb, NFTA_MATCH_INFO, info,
551 match->matchsize, match->usersize))
552 goto nla_put_failure;
553
554 return 0;
555
556nla_put_failure:
557 return -1;
558}
559
560static int nft_match_dump(struct sk_buff *skb, const struct nft_expr *expr)
561{
562 return __nft_match_dump(skb, expr, nft_expr_priv(expr));
563}
564
565static int nft_match_large_dump(struct sk_buff *skb, const struct nft_expr *e)
566{
567 struct nft_xt_match_priv *priv = nft_expr_priv(e);
568
569 return __nft_match_dump(skb, e, priv->info);
570}
571
572static int nft_match_validate(const struct nft_ctx *ctx,
573 const struct nft_expr *expr,
574 const struct nft_data **data)
575{
576 struct xt_match *match = expr->ops->data;
577 unsigned int hook_mask = 0;
578 int ret;
579
580 if (nft_is_base_chain(ctx->chain)) {
581 const struct nft_base_chain *basechain =
582 nft_base_chain(ctx->chain);
583 const struct nf_hook_ops *ops = &basechain->ops;
584
585 hook_mask = 1 << ops->hooknum;
586 if (match->hooks && !(hook_mask & match->hooks))
587 return -EINVAL;
588
589 ret = nft_compat_chain_validate_dependency(ctx, match->table);
590 if (ret < 0)
591 return ret;
592 }
593 return 0;
594}
595
596static int
597nfnl_compat_fill_info(struct sk_buff *skb, u32 portid, u32 seq, u32 type,
598 int event, u16 family, const char *name,
599 int rev, int target)
600{
601 struct nlmsghdr *nlh;
602 unsigned int flags = portid ? NLM_F_MULTI : 0;
603
604 event = nfnl_msg_type(NFNL_SUBSYS_NFT_COMPAT, event);
605 nlh = nfnl_msg_put(skb, portid, seq, event, flags, family,
606 NFNETLINK_V0, 0);
607 if (!nlh)
608 goto nlmsg_failure;
609
610 if (nla_put_string(skb, NFTA_COMPAT_NAME, name) ||
611 nla_put_be32(skb, NFTA_COMPAT_REV, htonl(rev)) ||
612 nla_put_be32(skb, NFTA_COMPAT_TYPE, htonl(target)))
613 goto nla_put_failure;
614
615 nlmsg_end(skb, nlh);
616 return skb->len;
617
618nlmsg_failure:
619nla_put_failure:
620 nlmsg_cancel(skb, nlh);
621 return -1;
622}
623
624static int nfnl_compat_get_rcu(struct sk_buff *skb,
625 const struct nfnl_info *info,
626 const struct nlattr * const tb[])
627{
628 u8 family = info->nfmsg->nfgen_family;
629 const char *name, *fmt;
630 struct sk_buff *skb2;
631 int ret = 0, target;
632 u32 rev;
633
634 if (tb[NFTA_COMPAT_NAME] == NULL ||
635 tb[NFTA_COMPAT_REV] == NULL ||
636 tb[NFTA_COMPAT_TYPE] == NULL)
637 return -EINVAL;
638
639 name = nla_data(tb[NFTA_COMPAT_NAME]);
640 rev = ntohl(nla_get_be32(tb[NFTA_COMPAT_REV]));
641 target = ntohl(nla_get_be32(tb[NFTA_COMPAT_TYPE]));
642
643 switch(family) {
644 case AF_INET:
645 fmt = "ipt_%s";
646 break;
647 case AF_INET6:
648 fmt = "ip6t_%s";
649 break;
650 case NFPROTO_BRIDGE:
651 fmt = "ebt_%s";
652 break;
653 case NFPROTO_ARP:
654 fmt = "arpt_%s";
655 break;
656 default:
657 pr_err("nft_compat: unsupported protocol %d\n", family);
658 return -EINVAL;
659 }
660
661 if (!try_module_get(THIS_MODULE))
662 return -EINVAL;
663
664 rcu_read_unlock();
665 try_then_request_module(xt_find_revision(family, name, rev, target, &ret),
666 fmt, name);
667 if (ret < 0)
668 goto out_put;
669
670 skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
671 if (skb2 == NULL) {
672 ret = -ENOMEM;
673 goto out_put;
674 }
675
676
677 if (nfnl_compat_fill_info(skb2, NETLINK_CB(skb).portid,
678 info->nlh->nlmsg_seq,
679 NFNL_MSG_TYPE(info->nlh->nlmsg_type),
680 NFNL_MSG_COMPAT_GET,
681 family, name, ret, target) <= 0) {
682 kfree_skb(skb2);
683 goto out_put;
684 }
685
686 ret = netlink_unicast(info->sk, skb2, NETLINK_CB(skb).portid,
687 MSG_DONTWAIT);
688 if (ret > 0)
689 ret = 0;
690out_put:
691 rcu_read_lock();
692 module_put(THIS_MODULE);
693 return ret == -EAGAIN ? -ENOBUFS : ret;
694}
695
696static const struct nla_policy nfnl_compat_policy_get[NFTA_COMPAT_MAX+1] = {
697 [NFTA_COMPAT_NAME] = { .type = NLA_NUL_STRING,
698 .len = NFT_COMPAT_NAME_MAX-1 },
699 [NFTA_COMPAT_REV] = { .type = NLA_U32 },
700 [NFTA_COMPAT_TYPE] = { .type = NLA_U32 },
701};
702
703static const struct nfnl_callback nfnl_nft_compat_cb[NFNL_MSG_COMPAT_MAX] = {
704 [NFNL_MSG_COMPAT_GET] = {
705 .call = nfnl_compat_get_rcu,
706 .type = NFNL_CB_RCU,
707 .attr_count = NFTA_COMPAT_MAX,
708 .policy = nfnl_compat_policy_get
709 },
710};
711
712static const struct nfnetlink_subsystem nfnl_compat_subsys = {
713 .name = "nft-compat",
714 .subsys_id = NFNL_SUBSYS_NFT_COMPAT,
715 .cb_count = NFNL_MSG_COMPAT_MAX,
716 .cb = nfnl_nft_compat_cb,
717};
718
719static struct nft_expr_type nft_match_type;
720
721static const struct nft_expr_ops *
722nft_match_select_ops(const struct nft_ctx *ctx,
723 const struct nlattr * const tb[])
724{
725 struct nft_expr_ops *ops;
726 struct xt_match *match;
727 unsigned int matchsize;
728 char *mt_name;
729 u32 rev, family;
730 int err;
731
732 if (tb[NFTA_MATCH_NAME] == NULL ||
733 tb[NFTA_MATCH_REV] == NULL ||
734 tb[NFTA_MATCH_INFO] == NULL)
735 return ERR_PTR(-EINVAL);
736
737 mt_name = nla_data(tb[NFTA_MATCH_NAME]);
738 rev = ntohl(nla_get_be32(tb[NFTA_MATCH_REV]));
739 family = ctx->family;
740
741 match = xt_request_find_match(family, mt_name, rev);
742 if (IS_ERR(match))
743 return ERR_PTR(-ENOENT);
744
745 if (match->matchsize > nla_len(tb[NFTA_MATCH_INFO])) {
746 err = -EINVAL;
747 goto err;
748 }
749
750 ops = kzalloc(sizeof(struct nft_expr_ops), GFP_KERNEL);
751 if (!ops) {
752 err = -ENOMEM;
753 goto err;
754 }
755
756 ops->type = &nft_match_type;
757 ops->eval = nft_match_eval;
758 ops->init = nft_match_init;
759 ops->destroy = nft_match_destroy;
760 ops->dump = nft_match_dump;
761 ops->validate = nft_match_validate;
762 ops->data = match;
763
764 matchsize = NFT_EXPR_SIZE(XT_ALIGN(match->matchsize));
765 if (matchsize > NFT_MATCH_LARGE_THRESH) {
766 matchsize = NFT_EXPR_SIZE(sizeof(struct nft_xt_match_priv));
767
768 ops->eval = nft_match_large_eval;
769 ops->init = nft_match_large_init;
770 ops->destroy = nft_match_large_destroy;
771 ops->dump = nft_match_large_dump;
772 }
773
774 ops->size = matchsize;
775
776 return ops;
777err:
778 module_put(match->me);
779 return ERR_PTR(err);
780}
781
782static void nft_match_release_ops(const struct nft_expr_ops *ops)
783{
784 struct xt_match *match = ops->data;
785
786 module_put(match->me);
787 kfree(ops);
788}
789
790static struct nft_expr_type nft_match_type __read_mostly = {
791 .name = "match",
792 .select_ops = nft_match_select_ops,
793 .release_ops = nft_match_release_ops,
794 .policy = nft_match_policy,
795 .maxattr = NFTA_MATCH_MAX,
796 .owner = THIS_MODULE,
797};
798
799static struct nft_expr_type nft_target_type;
800
801static const struct nft_expr_ops *
802nft_target_select_ops(const struct nft_ctx *ctx,
803 const struct nlattr * const tb[])
804{
805 struct nft_expr_ops *ops;
806 struct xt_target *target;
807 char *tg_name;
808 u32 rev, family;
809 int err;
810
811 if (tb[NFTA_TARGET_NAME] == NULL ||
812 tb[NFTA_TARGET_REV] == NULL ||
813 tb[NFTA_TARGET_INFO] == NULL)
814 return ERR_PTR(-EINVAL);
815
816 tg_name = nla_data(tb[NFTA_TARGET_NAME]);
817 rev = ntohl(nla_get_be32(tb[NFTA_TARGET_REV]));
818 family = ctx->family;
819
820 if (strcmp(tg_name, XT_ERROR_TARGET) == 0 ||
821 strcmp(tg_name, XT_STANDARD_TARGET) == 0 ||
822 strcmp(tg_name, "standard") == 0)
823 return ERR_PTR(-EINVAL);
824
825 target = xt_request_find_target(family, tg_name, rev);
826 if (IS_ERR(target))
827 return ERR_PTR(-ENOENT);
828
829 if (!target->target) {
830 err = -EINVAL;
831 goto err;
832 }
833
834 if (target->targetsize > nla_len(tb[NFTA_TARGET_INFO])) {
835 err = -EINVAL;
836 goto err;
837 }
838
839 ops = kzalloc(sizeof(struct nft_expr_ops), GFP_KERNEL);
840 if (!ops) {
841 err = -ENOMEM;
842 goto err;
843 }
844
845 ops->type = &nft_target_type;
846 ops->size = NFT_EXPR_SIZE(XT_ALIGN(target->targetsize));
847 ops->init = nft_target_init;
848 ops->destroy = nft_target_destroy;
849 ops->dump = nft_target_dump;
850 ops->validate = nft_target_validate;
851 ops->data = target;
852
853 if (family == NFPROTO_BRIDGE)
854 ops->eval = nft_target_eval_bridge;
855 else
856 ops->eval = nft_target_eval_xt;
857
858 return ops;
859err:
860 module_put(target->me);
861 return ERR_PTR(err);
862}
863
864static void nft_target_release_ops(const struct nft_expr_ops *ops)
865{
866 struct xt_target *target = ops->data;
867
868 module_put(target->me);
869 kfree(ops);
870}
871
872static struct nft_expr_type nft_target_type __read_mostly = {
873 .name = "target",
874 .select_ops = nft_target_select_ops,
875 .release_ops = nft_target_release_ops,
876 .policy = nft_target_policy,
877 .maxattr = NFTA_TARGET_MAX,
878 .owner = THIS_MODULE,
879};
880
881static int __init nft_compat_module_init(void)
882{
883 int ret;
884
885 ret = nft_register_expr(&nft_match_type);
886 if (ret < 0)
887 return ret;
888
889 ret = nft_register_expr(&nft_target_type);
890 if (ret < 0)
891 goto err_match;
892
893 ret = nfnetlink_subsys_register(&nfnl_compat_subsys);
894 if (ret < 0) {
895 pr_err("nft_compat: cannot register with nfnetlink.\n");
896 goto err_target;
897 }
898
899 return ret;
900err_target:
901 nft_unregister_expr(&nft_target_type);
902err_match:
903 nft_unregister_expr(&nft_match_type);
904 return ret;
905}
906
907static void __exit nft_compat_module_exit(void)
908{
909 nfnetlink_subsys_unregister(&nfnl_compat_subsys);
910 nft_unregister_expr(&nft_target_type);
911 nft_unregister_expr(&nft_match_type);
912}
913
914MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_NFT_COMPAT);
915
916module_init(nft_compat_module_init);
917module_exit(nft_compat_module_exit);
918
919MODULE_LICENSE("GPL");
920MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
921MODULE_ALIAS_NFT_EXPR("match");
922MODULE_ALIAS_NFT_EXPR("target");
923MODULE_DESCRIPTION("x_tables over nftables support");
924
