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v5.14.15
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
  4 *
  5 * Development of this code funded by Astaro AG (http://www.astaro.com/)
  6 */
  7
  8#include <linux/kernel.h>
  9#include <linux/init.h>
 10#include <linux/module.h>
 11#include <linux/spinlock.h>
 12#include <linux/netlink.h>
 13#include <linux/netfilter.h>
 14#include <linux/netfilter/nf_tables.h>
 15#include <net/netfilter/nf_tables.h>
 16
 17struct nft_limit {
 18	spinlock_t	lock;
 19	u64		last;
 20	u64		tokens;
 
 
 
 
 21	u64		tokens_max;
 22	u64		rate;
 23	u64		nsecs;
 24	u32		burst;
 25	bool		invert;
 26};
 27
 28static inline bool nft_limit_eval(struct nft_limit *limit, u64 cost)
 29{
 30	u64 now, tokens;
 31	s64 delta;
 32
 33	spin_lock_bh(&limit->lock);
 34	now = ktime_get_ns();
 35	tokens = limit->tokens + now - limit->last;
 36	if (tokens > limit->tokens_max)
 37		tokens = limit->tokens_max;
 38
 39	limit->last = now;
 40	delta = tokens - cost;
 41	if (delta >= 0) {
 42		limit->tokens = delta;
 43		spin_unlock_bh(&limit->lock);
 44		return limit->invert;
 45	}
 46	limit->tokens = tokens;
 47	spin_unlock_bh(&limit->lock);
 48	return !limit->invert;
 49}
 50
 51/* Use same default as in iptables. */
 52#define NFT_LIMIT_PKT_BURST_DEFAULT	5
 53
 54static int nft_limit_init(struct nft_limit *limit,
 55			  const struct nlattr * const tb[], bool pkts)
 56{
 57	u64 unit, tokens;
 
 58
 59	if (tb[NFTA_LIMIT_RATE] == NULL ||
 60	    tb[NFTA_LIMIT_UNIT] == NULL)
 61		return -EINVAL;
 62
 63	limit->rate = be64_to_cpu(nla_get_be64(tb[NFTA_LIMIT_RATE]));
 
 
 
 64	unit = be64_to_cpu(nla_get_be64(tb[NFTA_LIMIT_UNIT]));
 65	limit->nsecs = unit * NSEC_PER_SEC;
 66	if (limit->rate == 0 || limit->nsecs < unit)
 67		return -EOVERFLOW;
 68
 69	if (tb[NFTA_LIMIT_BURST])
 70		limit->burst = ntohl(nla_get_be32(tb[NFTA_LIMIT_BURST]));
 71
 72	if (pkts && limit->burst == 0)
 73		limit->burst = NFT_LIMIT_PKT_BURST_DEFAULT;
 74
 75	if (limit->rate + limit->burst < limit->rate)
 76		return -EOVERFLOW;
 77
 78	if (pkts) {
 79		tokens = div64_u64(limit->nsecs, limit->rate) * limit->burst;
 
 
 
 80	} else {
 
 
 81		/* The token bucket size limits the number of tokens can be
 82		 * accumulated. tokens_max specifies the bucket size.
 83		 * tokens_max = unit * (rate + burst) / rate.
 84		 */
 85		tokens = div64_u64(limit->nsecs * (limit->rate + limit->burst),
 86				 limit->rate);
 87	}
 88
 89	limit->tokens = tokens;
 90	limit->tokens_max = limit->tokens;
 91
 92	if (tb[NFTA_LIMIT_FLAGS]) {
 93		u32 flags = ntohl(nla_get_be32(tb[NFTA_LIMIT_FLAGS]));
 94
 
 
 
 95		if (flags & NFT_LIMIT_F_INV)
 96			limit->invert = true;
 97	}
 98	limit->last = ktime_get_ns();
 99	spin_lock_init(&limit->lock);
 
 
 
 
 
 
 
 
100
101	return 0;
102}
103
104static int nft_limit_dump(struct sk_buff *skb, const struct nft_limit *limit,
105			  enum nft_limit_type type)
106{
107	u32 flags = limit->invert ? NFT_LIMIT_F_INV : 0;
108	u64 secs = div_u64(limit->nsecs, NSEC_PER_SEC);
109
110	if (nla_put_be64(skb, NFTA_LIMIT_RATE, cpu_to_be64(limit->rate),
111			 NFTA_LIMIT_PAD) ||
112	    nla_put_be64(skb, NFTA_LIMIT_UNIT, cpu_to_be64(secs),
113			 NFTA_LIMIT_PAD) ||
114	    nla_put_be32(skb, NFTA_LIMIT_BURST, htonl(limit->burst)) ||
115	    nla_put_be32(skb, NFTA_LIMIT_TYPE, htonl(type)) ||
116	    nla_put_be32(skb, NFTA_LIMIT_FLAGS, htonl(flags)))
117		goto nla_put_failure;
118	return 0;
119
120nla_put_failure:
121	return -1;
122}
123
124struct nft_limit_pkts {
125	struct nft_limit	limit;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
126	u64			cost;
127};
128
129static void nft_limit_pkts_eval(const struct nft_expr *expr,
130				struct nft_regs *regs,
131				const struct nft_pktinfo *pkt)
132{
133	struct nft_limit_pkts *priv = nft_expr_priv(expr);
134
135	if (nft_limit_eval(&priv->limit, priv->cost))
136		regs->verdict.code = NFT_BREAK;
137}
138
139static const struct nla_policy nft_limit_policy[NFTA_LIMIT_MAX + 1] = {
140	[NFTA_LIMIT_RATE]	= { .type = NLA_U64 },
141	[NFTA_LIMIT_UNIT]	= { .type = NLA_U64 },
142	[NFTA_LIMIT_BURST]	= { .type = NLA_U32 },
143	[NFTA_LIMIT_TYPE]	= { .type = NLA_U32 },
144	[NFTA_LIMIT_FLAGS]	= { .type = NLA_U32 },
145};
146
147static int nft_limit_pkts_init(const struct nft_ctx *ctx,
148			       const struct nft_expr *expr,
149			       const struct nlattr * const tb[])
150{
151	struct nft_limit_pkts *priv = nft_expr_priv(expr);
152	int err;
153
154	err = nft_limit_init(&priv->limit, tb, true);
155	if (err < 0)
156		return err;
157
158	priv->cost = div64_u64(priv->limit.nsecs, priv->limit.rate);
159	return 0;
160}
161
162static int nft_limit_pkts_dump(struct sk_buff *skb, const struct nft_expr *expr)
 
163{
164	const struct nft_limit_pkts *priv = nft_expr_priv(expr);
165
166	return nft_limit_dump(skb, &priv->limit, NFT_LIMIT_PKTS);
167}
168
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
169static struct nft_expr_type nft_limit_type;
170static const struct nft_expr_ops nft_limit_pkts_ops = {
171	.type		= &nft_limit_type,
172	.size		= NFT_EXPR_SIZE(sizeof(struct nft_limit_pkts)),
173	.eval		= nft_limit_pkts_eval,
174	.init		= nft_limit_pkts_init,
 
 
175	.dump		= nft_limit_pkts_dump,
 
176};
177
178static void nft_limit_bytes_eval(const struct nft_expr *expr,
179				 struct nft_regs *regs,
180				 const struct nft_pktinfo *pkt)
181{
182	struct nft_limit *priv = nft_expr_priv(expr);
183	u64 cost = div64_u64(priv->nsecs * pkt->skb->len, priv->rate);
184
185	if (nft_limit_eval(priv, cost))
186		regs->verdict.code = NFT_BREAK;
187}
188
189static int nft_limit_bytes_init(const struct nft_ctx *ctx,
190				const struct nft_expr *expr,
191				const struct nlattr * const tb[])
192{
193	struct nft_limit *priv = nft_expr_priv(expr);
194
195	return nft_limit_init(priv, tb, false);
196}
197
198static int nft_limit_bytes_dump(struct sk_buff *skb,
199				const struct nft_expr *expr)
200{
201	const struct nft_limit *priv = nft_expr_priv(expr);
202
203	return nft_limit_dump(skb, priv, NFT_LIMIT_PKT_BYTES);
204}
205
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
206static const struct nft_expr_ops nft_limit_bytes_ops = {
207	.type		= &nft_limit_type,
208	.size		= NFT_EXPR_SIZE(sizeof(struct nft_limit)),
209	.eval		= nft_limit_bytes_eval,
210	.init		= nft_limit_bytes_init,
211	.dump		= nft_limit_bytes_dump,
 
 
 
212};
213
214static const struct nft_expr_ops *
215nft_limit_select_ops(const struct nft_ctx *ctx,
216		     const struct nlattr * const tb[])
217{
218	if (tb[NFTA_LIMIT_TYPE] == NULL)
219		return &nft_limit_pkts_ops;
220
221	switch (ntohl(nla_get_be32(tb[NFTA_LIMIT_TYPE]))) {
222	case NFT_LIMIT_PKTS:
223		return &nft_limit_pkts_ops;
224	case NFT_LIMIT_PKT_BYTES:
225		return &nft_limit_bytes_ops;
226	}
227	return ERR_PTR(-EOPNOTSUPP);
228}
229
230static struct nft_expr_type nft_limit_type __read_mostly = {
231	.name		= "limit",
232	.select_ops	= nft_limit_select_ops,
233	.policy		= nft_limit_policy,
234	.maxattr	= NFTA_LIMIT_MAX,
235	.flags		= NFT_EXPR_STATEFUL,
236	.owner		= THIS_MODULE,
237};
238
239static void nft_limit_obj_pkts_eval(struct nft_object *obj,
240				    struct nft_regs *regs,
241				    const struct nft_pktinfo *pkt)
242{
243	struct nft_limit_pkts *priv = nft_obj_data(obj);
244
245	if (nft_limit_eval(&priv->limit, priv->cost))
246		regs->verdict.code = NFT_BREAK;
247}
248
249static int nft_limit_obj_pkts_init(const struct nft_ctx *ctx,
250				   const struct nlattr * const tb[],
251				   struct nft_object *obj)
252{
253	struct nft_limit_pkts *priv = nft_obj_data(obj);
254	int err;
255
256	err = nft_limit_init(&priv->limit, tb, true);
257	if (err < 0)
258		return err;
259
260	priv->cost = div64_u64(priv->limit.nsecs, priv->limit.rate);
261	return 0;
262}
263
264static int nft_limit_obj_pkts_dump(struct sk_buff *skb,
265				   struct nft_object *obj,
266				   bool reset)
267{
268	const struct nft_limit_pkts *priv = nft_obj_data(obj);
269
270	return nft_limit_dump(skb, &priv->limit, NFT_LIMIT_PKTS);
271}
272
 
 
 
 
 
 
 
 
273static struct nft_object_type nft_limit_obj_type;
274static const struct nft_object_ops nft_limit_obj_pkts_ops = {
275	.type		= &nft_limit_obj_type,
276	.size		= NFT_EXPR_SIZE(sizeof(struct nft_limit_pkts)),
277	.init		= nft_limit_obj_pkts_init,
 
278	.eval		= nft_limit_obj_pkts_eval,
279	.dump		= nft_limit_obj_pkts_dump,
280};
281
282static void nft_limit_obj_bytes_eval(struct nft_object *obj,
283				     struct nft_regs *regs,
284				     const struct nft_pktinfo *pkt)
285{
286	struct nft_limit *priv = nft_obj_data(obj);
287	u64 cost = div64_u64(priv->nsecs * pkt->skb->len, priv->rate);
288
289	if (nft_limit_eval(priv, cost))
290		regs->verdict.code = NFT_BREAK;
291}
292
293static int nft_limit_obj_bytes_init(const struct nft_ctx *ctx,
294				    const struct nlattr * const tb[],
295				    struct nft_object *obj)
296{
297	struct nft_limit *priv = nft_obj_data(obj);
298
299	return nft_limit_init(priv, tb, false);
300}
301
302static int nft_limit_obj_bytes_dump(struct sk_buff *skb,
303				    struct nft_object *obj,
304				    bool reset)
305{
306	const struct nft_limit *priv = nft_obj_data(obj);
307
308	return nft_limit_dump(skb, priv, NFT_LIMIT_PKT_BYTES);
309}
310
 
 
 
 
 
 
 
 
311static struct nft_object_type nft_limit_obj_type;
312static const struct nft_object_ops nft_limit_obj_bytes_ops = {
313	.type		= &nft_limit_obj_type,
314	.size		= sizeof(struct nft_limit),
315	.init		= nft_limit_obj_bytes_init,
 
316	.eval		= nft_limit_obj_bytes_eval,
317	.dump		= nft_limit_obj_bytes_dump,
318};
319
320static const struct nft_object_ops *
321nft_limit_obj_select_ops(const struct nft_ctx *ctx,
322			 const struct nlattr * const tb[])
323{
324	if (!tb[NFTA_LIMIT_TYPE])
325		return &nft_limit_obj_pkts_ops;
326
327	switch (ntohl(nla_get_be32(tb[NFTA_LIMIT_TYPE]))) {
328	case NFT_LIMIT_PKTS:
329		return &nft_limit_obj_pkts_ops;
330	case NFT_LIMIT_PKT_BYTES:
331		return &nft_limit_obj_bytes_ops;
332	}
333	return ERR_PTR(-EOPNOTSUPP);
334}
335
336static struct nft_object_type nft_limit_obj_type __read_mostly = {
337	.select_ops	= nft_limit_obj_select_ops,
338	.type		= NFT_OBJECT_LIMIT,
339	.maxattr	= NFTA_LIMIT_MAX,
340	.policy		= nft_limit_policy,
341	.owner		= THIS_MODULE,
342};
343
344static int __init nft_limit_module_init(void)
345{
346	int err;
347
348	err = nft_register_obj(&nft_limit_obj_type);
349	if (err < 0)
350		return err;
351
352	err = nft_register_expr(&nft_limit_type);
353	if (err < 0)
354		goto err1;
355
356	return 0;
357err1:
358	nft_unregister_obj(&nft_limit_obj_type);
359	return err;
360}
361
362static void __exit nft_limit_module_exit(void)
363{
364	nft_unregister_expr(&nft_limit_type);
365	nft_unregister_obj(&nft_limit_obj_type);
366}
367
368module_init(nft_limit_module_init);
369module_exit(nft_limit_module_exit);
370
371MODULE_LICENSE("GPL");
372MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
373MODULE_ALIAS_NFT_EXPR("limit");
374MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_LIMIT);
375MODULE_DESCRIPTION("nftables limit expression support");
v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
  4 *
  5 * Development of this code funded by Astaro AG (http://www.astaro.com/)
  6 */
  7
  8#include <linux/kernel.h>
  9#include <linux/init.h>
 10#include <linux/module.h>
 11#include <linux/spinlock.h>
 12#include <linux/netlink.h>
 13#include <linux/netfilter.h>
 14#include <linux/netfilter/nf_tables.h>
 15#include <net/netfilter/nf_tables.h>
 16
 17struct nft_limit {
 18	spinlock_t	lock;
 19	u64		last;
 20	u64		tokens;
 21};
 22
 23struct nft_limit_priv {
 24	struct nft_limit *limit;
 25	u64		tokens_max;
 26	u64		rate;
 27	u64		nsecs;
 28	u32		burst;
 29	bool		invert;
 30};
 31
 32static inline bool nft_limit_eval(struct nft_limit_priv *priv, u64 cost)
 33{
 34	u64 now, tokens;
 35	s64 delta;
 36
 37	spin_lock_bh(&priv->limit->lock);
 38	now = ktime_get_ns();
 39	tokens = priv->limit->tokens + now - priv->limit->last;
 40	if (tokens > priv->tokens_max)
 41		tokens = priv->tokens_max;
 42
 43	priv->limit->last = now;
 44	delta = tokens - cost;
 45	if (delta >= 0) {
 46		priv->limit->tokens = delta;
 47		spin_unlock_bh(&priv->limit->lock);
 48		return priv->invert;
 49	}
 50	priv->limit->tokens = tokens;
 51	spin_unlock_bh(&priv->limit->lock);
 52	return !priv->invert;
 53}
 54
 55/* Use same default as in iptables. */
 56#define NFT_LIMIT_PKT_BURST_DEFAULT	5
 57
 58static int nft_limit_init(struct nft_limit_priv *priv,
 59			  const struct nlattr * const tb[], bool pkts)
 60{
 61	u64 unit, tokens, rate_with_burst;
 62	bool invert = false;
 63
 64	if (tb[NFTA_LIMIT_RATE] == NULL ||
 65	    tb[NFTA_LIMIT_UNIT] == NULL)
 66		return -EINVAL;
 67
 68	priv->rate = be64_to_cpu(nla_get_be64(tb[NFTA_LIMIT_RATE]));
 69	if (priv->rate == 0)
 70		return -EINVAL;
 71
 72	unit = be64_to_cpu(nla_get_be64(tb[NFTA_LIMIT_UNIT]));
 73	if (check_mul_overflow(unit, NSEC_PER_SEC, &priv->nsecs))
 
 74		return -EOVERFLOW;
 75
 76	if (tb[NFTA_LIMIT_BURST])
 77		priv->burst = ntohl(nla_get_be32(tb[NFTA_LIMIT_BURST]));
 78
 79	if (pkts && priv->burst == 0)
 80		priv->burst = NFT_LIMIT_PKT_BURST_DEFAULT;
 81
 82	if (check_add_overflow(priv->rate, priv->burst, &rate_with_burst))
 83		return -EOVERFLOW;
 84
 85	if (pkts) {
 86		u64 tmp = div64_u64(priv->nsecs, priv->rate);
 87
 88		if (check_mul_overflow(tmp, priv->burst, &tokens))
 89			return -EOVERFLOW;
 90	} else {
 91		u64 tmp;
 92
 93		/* The token bucket size limits the number of tokens can be
 94		 * accumulated. tokens_max specifies the bucket size.
 95		 * tokens_max = unit * (rate + burst) / rate.
 96		 */
 97		if (check_mul_overflow(priv->nsecs, rate_with_burst, &tmp))
 98			return -EOVERFLOW;
 
 99
100		tokens = div64_u64(tmp, priv->rate);
101	}
102
103	if (tb[NFTA_LIMIT_FLAGS]) {
104		u32 flags = ntohl(nla_get_be32(tb[NFTA_LIMIT_FLAGS]));
105
106		if (flags & ~NFT_LIMIT_F_INV)
107			return -EOPNOTSUPP;
108
109		if (flags & NFT_LIMIT_F_INV)
110			invert = true;
111	}
112
113	priv->limit = kmalloc(sizeof(*priv->limit), GFP_KERNEL_ACCOUNT);
114	if (!priv->limit)
115		return -ENOMEM;
116
117	priv->limit->tokens = tokens;
118	priv->tokens_max = priv->limit->tokens;
119	priv->invert = invert;
120	priv->limit->last = ktime_get_ns();
121	spin_lock_init(&priv->limit->lock);
122
123	return 0;
124}
125
126static int nft_limit_dump(struct sk_buff *skb, const struct nft_limit_priv *priv,
127			  enum nft_limit_type type)
128{
129	u32 flags = priv->invert ? NFT_LIMIT_F_INV : 0;
130	u64 secs = div_u64(priv->nsecs, NSEC_PER_SEC);
131
132	if (nla_put_be64(skb, NFTA_LIMIT_RATE, cpu_to_be64(priv->rate),
133			 NFTA_LIMIT_PAD) ||
134	    nla_put_be64(skb, NFTA_LIMIT_UNIT, cpu_to_be64(secs),
135			 NFTA_LIMIT_PAD) ||
136	    nla_put_be32(skb, NFTA_LIMIT_BURST, htonl(priv->burst)) ||
137	    nla_put_be32(skb, NFTA_LIMIT_TYPE, htonl(type)) ||
138	    nla_put_be32(skb, NFTA_LIMIT_FLAGS, htonl(flags)))
139		goto nla_put_failure;
140	return 0;
141
142nla_put_failure:
143	return -1;
144}
145
146static void nft_limit_destroy(const struct nft_ctx *ctx,
147			      const struct nft_limit_priv *priv)
148{
149	kfree(priv->limit);
150}
151
152static int nft_limit_clone(struct nft_limit_priv *priv_dst,
153			   const struct nft_limit_priv *priv_src, gfp_t gfp)
154{
155	priv_dst->tokens_max = priv_src->tokens_max;
156	priv_dst->rate = priv_src->rate;
157	priv_dst->nsecs = priv_src->nsecs;
158	priv_dst->burst = priv_src->burst;
159	priv_dst->invert = priv_src->invert;
160
161	priv_dst->limit = kmalloc(sizeof(*priv_dst->limit), gfp);
162	if (!priv_dst->limit)
163		return -ENOMEM;
164
165	spin_lock_init(&priv_dst->limit->lock);
166	priv_dst->limit->tokens = priv_src->tokens_max;
167	priv_dst->limit->last = ktime_get_ns();
168
169	return 0;
170}
171
172struct nft_limit_priv_pkts {
173	struct nft_limit_priv	limit;
174	u64			cost;
175};
176
177static void nft_limit_pkts_eval(const struct nft_expr *expr,
178				struct nft_regs *regs,
179				const struct nft_pktinfo *pkt)
180{
181	struct nft_limit_priv_pkts *priv = nft_expr_priv(expr);
182
183	if (nft_limit_eval(&priv->limit, priv->cost))
184		regs->verdict.code = NFT_BREAK;
185}
186
187static const struct nla_policy nft_limit_policy[NFTA_LIMIT_MAX + 1] = {
188	[NFTA_LIMIT_RATE]	= { .type = NLA_U64 },
189	[NFTA_LIMIT_UNIT]	= { .type = NLA_U64 },
190	[NFTA_LIMIT_BURST]	= { .type = NLA_U32 },
191	[NFTA_LIMIT_TYPE]	= { .type = NLA_U32 },
192	[NFTA_LIMIT_FLAGS]	= { .type = NLA_U32 },
193};
194
195static int nft_limit_pkts_init(const struct nft_ctx *ctx,
196			       const struct nft_expr *expr,
197			       const struct nlattr * const tb[])
198{
199	struct nft_limit_priv_pkts *priv = nft_expr_priv(expr);
200	int err;
201
202	err = nft_limit_init(&priv->limit, tb, true);
203	if (err < 0)
204		return err;
205
206	priv->cost = div64_u64(priv->limit.nsecs, priv->limit.rate);
207	return 0;
208}
209
210static int nft_limit_pkts_dump(struct sk_buff *skb,
211			       const struct nft_expr *expr, bool reset)
212{
213	const struct nft_limit_priv_pkts *priv = nft_expr_priv(expr);
214
215	return nft_limit_dump(skb, &priv->limit, NFT_LIMIT_PKTS);
216}
217
218static void nft_limit_pkts_destroy(const struct nft_ctx *ctx,
219				   const struct nft_expr *expr)
220{
221	const struct nft_limit_priv_pkts *priv = nft_expr_priv(expr);
222
223	nft_limit_destroy(ctx, &priv->limit);
224}
225
226static int nft_limit_pkts_clone(struct nft_expr *dst, const struct nft_expr *src,
227				gfp_t gfp)
228{
229	struct nft_limit_priv_pkts *priv_dst = nft_expr_priv(dst);
230	struct nft_limit_priv_pkts *priv_src = nft_expr_priv(src);
231
232	priv_dst->cost = priv_src->cost;
233
234	return nft_limit_clone(&priv_dst->limit, &priv_src->limit, gfp);
235}
236
237static struct nft_expr_type nft_limit_type;
238static const struct nft_expr_ops nft_limit_pkts_ops = {
239	.type		= &nft_limit_type,
240	.size		= NFT_EXPR_SIZE(sizeof(struct nft_limit_priv_pkts)),
241	.eval		= nft_limit_pkts_eval,
242	.init		= nft_limit_pkts_init,
243	.destroy	= nft_limit_pkts_destroy,
244	.clone		= nft_limit_pkts_clone,
245	.dump		= nft_limit_pkts_dump,
246	.reduce		= NFT_REDUCE_READONLY,
247};
248
249static void nft_limit_bytes_eval(const struct nft_expr *expr,
250				 struct nft_regs *regs,
251				 const struct nft_pktinfo *pkt)
252{
253	struct nft_limit_priv *priv = nft_expr_priv(expr);
254	u64 cost = div64_u64(priv->nsecs * pkt->skb->len, priv->rate);
255
256	if (nft_limit_eval(priv, cost))
257		regs->verdict.code = NFT_BREAK;
258}
259
260static int nft_limit_bytes_init(const struct nft_ctx *ctx,
261				const struct nft_expr *expr,
262				const struct nlattr * const tb[])
263{
264	struct nft_limit_priv *priv = nft_expr_priv(expr);
265
266	return nft_limit_init(priv, tb, false);
267}
268
269static int nft_limit_bytes_dump(struct sk_buff *skb,
270				const struct nft_expr *expr, bool reset)
271{
272	const struct nft_limit_priv *priv = nft_expr_priv(expr);
273
274	return nft_limit_dump(skb, priv, NFT_LIMIT_PKT_BYTES);
275}
276
277static void nft_limit_bytes_destroy(const struct nft_ctx *ctx,
278				    const struct nft_expr *expr)
279{
280	const struct nft_limit_priv *priv = nft_expr_priv(expr);
281
282	nft_limit_destroy(ctx, priv);
283}
284
285static int nft_limit_bytes_clone(struct nft_expr *dst, const struct nft_expr *src,
286				 gfp_t gfp)
287{
288	struct nft_limit_priv *priv_dst = nft_expr_priv(dst);
289	struct nft_limit_priv *priv_src = nft_expr_priv(src);
290
291	return nft_limit_clone(priv_dst, priv_src, gfp);
292}
293
294static const struct nft_expr_ops nft_limit_bytes_ops = {
295	.type		= &nft_limit_type,
296	.size		= NFT_EXPR_SIZE(sizeof(struct nft_limit_priv)),
297	.eval		= nft_limit_bytes_eval,
298	.init		= nft_limit_bytes_init,
299	.dump		= nft_limit_bytes_dump,
300	.clone		= nft_limit_bytes_clone,
301	.destroy	= nft_limit_bytes_destroy,
302	.reduce		= NFT_REDUCE_READONLY,
303};
304
305static const struct nft_expr_ops *
306nft_limit_select_ops(const struct nft_ctx *ctx,
307		     const struct nlattr * const tb[])
308{
309	if (tb[NFTA_LIMIT_TYPE] == NULL)
310		return &nft_limit_pkts_ops;
311
312	switch (ntohl(nla_get_be32(tb[NFTA_LIMIT_TYPE]))) {
313	case NFT_LIMIT_PKTS:
314		return &nft_limit_pkts_ops;
315	case NFT_LIMIT_PKT_BYTES:
316		return &nft_limit_bytes_ops;
317	}
318	return ERR_PTR(-EOPNOTSUPP);
319}
320
321static struct nft_expr_type nft_limit_type __read_mostly = {
322	.name		= "limit",
323	.select_ops	= nft_limit_select_ops,
324	.policy		= nft_limit_policy,
325	.maxattr	= NFTA_LIMIT_MAX,
326	.flags		= NFT_EXPR_STATEFUL,
327	.owner		= THIS_MODULE,
328};
329
330static void nft_limit_obj_pkts_eval(struct nft_object *obj,
331				    struct nft_regs *regs,
332				    const struct nft_pktinfo *pkt)
333{
334	struct nft_limit_priv_pkts *priv = nft_obj_data(obj);
335
336	if (nft_limit_eval(&priv->limit, priv->cost))
337		regs->verdict.code = NFT_BREAK;
338}
339
340static int nft_limit_obj_pkts_init(const struct nft_ctx *ctx,
341				   const struct nlattr * const tb[],
342				   struct nft_object *obj)
343{
344	struct nft_limit_priv_pkts *priv = nft_obj_data(obj);
345	int err;
346
347	err = nft_limit_init(&priv->limit, tb, true);
348	if (err < 0)
349		return err;
350
351	priv->cost = div64_u64(priv->limit.nsecs, priv->limit.rate);
352	return 0;
353}
354
355static int nft_limit_obj_pkts_dump(struct sk_buff *skb,
356				   struct nft_object *obj,
357				   bool reset)
358{
359	const struct nft_limit_priv_pkts *priv = nft_obj_data(obj);
360
361	return nft_limit_dump(skb, &priv->limit, NFT_LIMIT_PKTS);
362}
363
364static void nft_limit_obj_pkts_destroy(const struct nft_ctx *ctx,
365				       struct nft_object *obj)
366{
367	struct nft_limit_priv_pkts *priv = nft_obj_data(obj);
368
369	nft_limit_destroy(ctx, &priv->limit);
370}
371
372static struct nft_object_type nft_limit_obj_type;
373static const struct nft_object_ops nft_limit_obj_pkts_ops = {
374	.type		= &nft_limit_obj_type,
375	.size		= NFT_EXPR_SIZE(sizeof(struct nft_limit_priv_pkts)),
376	.init		= nft_limit_obj_pkts_init,
377	.destroy	= nft_limit_obj_pkts_destroy,
378	.eval		= nft_limit_obj_pkts_eval,
379	.dump		= nft_limit_obj_pkts_dump,
380};
381
382static void nft_limit_obj_bytes_eval(struct nft_object *obj,
383				     struct nft_regs *regs,
384				     const struct nft_pktinfo *pkt)
385{
386	struct nft_limit_priv *priv = nft_obj_data(obj);
387	u64 cost = div64_u64(priv->nsecs * pkt->skb->len, priv->rate);
388
389	if (nft_limit_eval(priv, cost))
390		regs->verdict.code = NFT_BREAK;
391}
392
393static int nft_limit_obj_bytes_init(const struct nft_ctx *ctx,
394				    const struct nlattr * const tb[],
395				    struct nft_object *obj)
396{
397	struct nft_limit_priv *priv = nft_obj_data(obj);
398
399	return nft_limit_init(priv, tb, false);
400}
401
402static int nft_limit_obj_bytes_dump(struct sk_buff *skb,
403				    struct nft_object *obj,
404				    bool reset)
405{
406	const struct nft_limit_priv *priv = nft_obj_data(obj);
407
408	return nft_limit_dump(skb, priv, NFT_LIMIT_PKT_BYTES);
409}
410
411static void nft_limit_obj_bytes_destroy(const struct nft_ctx *ctx,
412					struct nft_object *obj)
413{
414	struct nft_limit_priv *priv = nft_obj_data(obj);
415
416	nft_limit_destroy(ctx, priv);
417}
418
419static struct nft_object_type nft_limit_obj_type;
420static const struct nft_object_ops nft_limit_obj_bytes_ops = {
421	.type		= &nft_limit_obj_type,
422	.size		= sizeof(struct nft_limit_priv),
423	.init		= nft_limit_obj_bytes_init,
424	.destroy	= nft_limit_obj_bytes_destroy,
425	.eval		= nft_limit_obj_bytes_eval,
426	.dump		= nft_limit_obj_bytes_dump,
427};
428
429static const struct nft_object_ops *
430nft_limit_obj_select_ops(const struct nft_ctx *ctx,
431			 const struct nlattr * const tb[])
432{
433	if (!tb[NFTA_LIMIT_TYPE])
434		return &nft_limit_obj_pkts_ops;
435
436	switch (ntohl(nla_get_be32(tb[NFTA_LIMIT_TYPE]))) {
437	case NFT_LIMIT_PKTS:
438		return &nft_limit_obj_pkts_ops;
439	case NFT_LIMIT_PKT_BYTES:
440		return &nft_limit_obj_bytes_ops;
441	}
442	return ERR_PTR(-EOPNOTSUPP);
443}
444
445static struct nft_object_type nft_limit_obj_type __read_mostly = {
446	.select_ops	= nft_limit_obj_select_ops,
447	.type		= NFT_OBJECT_LIMIT,
448	.maxattr	= NFTA_LIMIT_MAX,
449	.policy		= nft_limit_policy,
450	.owner		= THIS_MODULE,
451};
452
453static int __init nft_limit_module_init(void)
454{
455	int err;
456
457	err = nft_register_obj(&nft_limit_obj_type);
458	if (err < 0)
459		return err;
460
461	err = nft_register_expr(&nft_limit_type);
462	if (err < 0)
463		goto err1;
464
465	return 0;
466err1:
467	nft_unregister_obj(&nft_limit_obj_type);
468	return err;
469}
470
471static void __exit nft_limit_module_exit(void)
472{
473	nft_unregister_expr(&nft_limit_type);
474	nft_unregister_obj(&nft_limit_obj_type);
475}
476
477module_init(nft_limit_module_init);
478module_exit(nft_limit_module_exit);
479
480MODULE_LICENSE("GPL");
481MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
482MODULE_ALIAS_NFT_EXPR("limit");
483MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_LIMIT);
484MODULE_DESCRIPTION("nftables limit expression support");