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/u64_stats_sync.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 #include <net/netfilter/nf_tables_core.h>
17 #include <net/netfilter/nf_tables_offload.h>
18
19 struct nft_counter {
20 u64_stats_t bytes;
21 u64_stats_t packets;
22 };
23
24 struct nft_counter_tot {
25 s64 bytes;
26 s64 packets;
27 };
28
29 struct nft_counter_percpu_priv {
30 struct nft_counter __percpu *counter;
31 };
32
33 static DEFINE_PER_CPU(struct u64_stats_sync, nft_counter_sync);
34
35 /* control plane only: sync fetch+reset */
36 static DEFINE_SPINLOCK(nft_counter_lock);
37
nft_counter_do_eval(struct nft_counter_percpu_priv * priv,struct nft_regs * regs,const struct nft_pktinfo * pkt)38 static inline void nft_counter_do_eval(struct nft_counter_percpu_priv *priv,
39 struct nft_regs *regs,
40 const struct nft_pktinfo *pkt)
41 {
42 struct u64_stats_sync *nft_sync;
43 struct nft_counter *this_cpu;
44
45 local_bh_disable();
46 this_cpu = this_cpu_ptr(priv->counter);
47 nft_sync = this_cpu_ptr(&nft_counter_sync);
48
49 u64_stats_update_begin(nft_sync);
50 u64_stats_add(&this_cpu->bytes, pkt->skb->len);
51 u64_stats_inc(&this_cpu->packets);
52 u64_stats_update_end(nft_sync);
53
54 local_bh_enable();
55 }
56
nft_counter_obj_eval(struct nft_object * obj,struct nft_regs * regs,const struct nft_pktinfo * pkt)57 static inline void nft_counter_obj_eval(struct nft_object *obj,
58 struct nft_regs *regs,
59 const struct nft_pktinfo *pkt)
60 {
61 struct nft_counter_percpu_priv *priv = nft_obj_data(obj);
62
63 nft_counter_do_eval(priv, regs, pkt);
64 }
65
nft_counter_do_init(const struct nlattr * const tb[],struct nft_counter_percpu_priv * priv)66 static int nft_counter_do_init(const struct nlattr * const tb[],
67 struct nft_counter_percpu_priv *priv)
68 {
69 struct nft_counter __percpu *cpu_stats;
70 struct nft_counter *this_cpu;
71
72 cpu_stats = alloc_percpu_gfp(struct nft_counter, GFP_KERNEL_ACCOUNT);
73 if (cpu_stats == NULL)
74 return -ENOMEM;
75
76 this_cpu = raw_cpu_ptr(cpu_stats);
77 if (tb[NFTA_COUNTER_PACKETS]) {
78 u64_stats_set(&this_cpu->packets,
79 be64_to_cpu(nla_get_be64(tb[NFTA_COUNTER_PACKETS])));
80 }
81 if (tb[NFTA_COUNTER_BYTES]) {
82 u64_stats_set(&this_cpu->bytes,
83 be64_to_cpu(nla_get_be64(tb[NFTA_COUNTER_BYTES])));
84 }
85
86 priv->counter = cpu_stats;
87 return 0;
88 }
89
nft_counter_obj_init(const struct nft_ctx * ctx,const struct nlattr * const tb[],struct nft_object * obj)90 static int nft_counter_obj_init(const struct nft_ctx *ctx,
91 const struct nlattr * const tb[],
92 struct nft_object *obj)
93 {
94 struct nft_counter_percpu_priv *priv = nft_obj_data(obj);
95
96 return nft_counter_do_init(tb, priv);
97 }
98
nft_counter_do_destroy(struct nft_counter_percpu_priv * priv)99 static void nft_counter_do_destroy(struct nft_counter_percpu_priv *priv)
100 {
101 free_percpu(priv->counter);
102 }
103
nft_counter_obj_destroy(const struct nft_ctx * ctx,struct nft_object * obj)104 static void nft_counter_obj_destroy(const struct nft_ctx *ctx,
105 struct nft_object *obj)
106 {
107 struct nft_counter_percpu_priv *priv = nft_obj_data(obj);
108
109 nft_counter_do_destroy(priv);
110 }
111
nft_counter_reset(struct nft_counter_percpu_priv * priv,struct nft_counter_tot * total)112 static void nft_counter_reset(struct nft_counter_percpu_priv *priv,
113 struct nft_counter_tot *total)
114 {
115 struct u64_stats_sync *nft_sync;
116 struct nft_counter *this_cpu;
117
118 local_bh_disable();
119 this_cpu = this_cpu_ptr(priv->counter);
120 nft_sync = this_cpu_ptr(&nft_counter_sync);
121
122 u64_stats_update_begin(nft_sync);
123 u64_stats_sub(&this_cpu->packets, total->packets);
124 u64_stats_sub(&this_cpu->bytes, total->bytes);
125 u64_stats_update_end(nft_sync);
126
127 local_bh_enable();
128 }
129
nft_counter_fetch(struct nft_counter_percpu_priv * priv,struct nft_counter_tot * total)130 static void nft_counter_fetch(struct nft_counter_percpu_priv *priv,
131 struct nft_counter_tot *total)
132 {
133 struct nft_counter *this_cpu;
134 u64 bytes, packets;
135 unsigned int seq;
136 int cpu;
137
138 memset(total, 0, sizeof(*total));
139 for_each_possible_cpu(cpu) {
140 struct u64_stats_sync *nft_sync = per_cpu_ptr(&nft_counter_sync, cpu);
141
142 this_cpu = per_cpu_ptr(priv->counter, cpu);
143 do {
144 seq = u64_stats_fetch_begin(nft_sync);
145 bytes = u64_stats_read(&this_cpu->bytes);
146 packets = u64_stats_read(&this_cpu->packets);
147 } while (u64_stats_fetch_retry(nft_sync, seq));
148
149 total->bytes += bytes;
150 total->packets += packets;
151 }
152 }
153
nft_counter_fetch_and_reset(struct nft_counter_percpu_priv * priv,struct nft_counter_tot * total)154 static void nft_counter_fetch_and_reset(struct nft_counter_percpu_priv *priv,
155 struct nft_counter_tot *total)
156 {
157 spin_lock(&nft_counter_lock);
158 nft_counter_fetch(priv, total);
159 nft_counter_reset(priv, total);
160 spin_unlock(&nft_counter_lock);
161 }
162
nft_counter_do_dump(struct sk_buff * skb,struct nft_counter_percpu_priv * priv,bool reset)163 static int nft_counter_do_dump(struct sk_buff *skb,
164 struct nft_counter_percpu_priv *priv,
165 bool reset)
166 {
167 struct nft_counter_tot total;
168
169 if (unlikely(reset))
170 nft_counter_fetch_and_reset(priv, &total);
171 else
172 nft_counter_fetch(priv, &total);
173
174 if (nla_put_be64(skb, NFTA_COUNTER_BYTES, cpu_to_be64(total.bytes),
175 NFTA_COUNTER_PAD) ||
176 nla_put_be64(skb, NFTA_COUNTER_PACKETS, cpu_to_be64(total.packets),
177 NFTA_COUNTER_PAD))
178 goto nla_put_failure;
179
180 return 0;
181
182 nla_put_failure:
183 return -1;
184 }
185
nft_counter_obj_dump(struct sk_buff * skb,struct nft_object * obj,bool reset)186 static int nft_counter_obj_dump(struct sk_buff *skb,
187 struct nft_object *obj, bool reset)
188 {
189 struct nft_counter_percpu_priv *priv = nft_obj_data(obj);
190
191 return nft_counter_do_dump(skb, priv, reset);
192 }
193
194 static const struct nla_policy nft_counter_policy[NFTA_COUNTER_MAX + 1] = {
195 [NFTA_COUNTER_PACKETS] = { .type = NLA_U64 },
196 [NFTA_COUNTER_BYTES] = { .type = NLA_U64 },
197 };
198
199 struct nft_object_type nft_counter_obj_type;
200 static const struct nft_object_ops nft_counter_obj_ops = {
201 .type = &nft_counter_obj_type,
202 .size = sizeof(struct nft_counter_percpu_priv),
203 .eval = nft_counter_obj_eval,
204 .init = nft_counter_obj_init,
205 .destroy = nft_counter_obj_destroy,
206 .dump = nft_counter_obj_dump,
207 };
208
209 struct nft_object_type nft_counter_obj_type __read_mostly = {
210 .type = NFT_OBJECT_COUNTER,
211 .ops = &nft_counter_obj_ops,
212 .maxattr = NFTA_COUNTER_MAX,
213 .policy = nft_counter_policy,
214 .owner = THIS_MODULE,
215 };
216
nft_counter_eval(const struct nft_expr * expr,struct nft_regs * regs,const struct nft_pktinfo * pkt)217 void nft_counter_eval(const struct nft_expr *expr, struct nft_regs *regs,
218 const struct nft_pktinfo *pkt)
219 {
220 struct nft_counter_percpu_priv *priv = nft_expr_priv(expr);
221
222 nft_counter_do_eval(priv, regs, pkt);
223 }
224
nft_counter_dump(struct sk_buff * skb,const struct nft_expr * expr,bool reset)225 static int nft_counter_dump(struct sk_buff *skb,
226 const struct nft_expr *expr, bool reset)
227 {
228 struct nft_counter_percpu_priv *priv = nft_expr_priv(expr);
229
230 return nft_counter_do_dump(skb, priv, reset);
231 }
232
nft_counter_init(const struct nft_ctx * ctx,const struct nft_expr * expr,const struct nlattr * const tb[])233 static int nft_counter_init(const struct nft_ctx *ctx,
234 const struct nft_expr *expr,
235 const struct nlattr * const tb[])
236 {
237 struct nft_counter_percpu_priv *priv = nft_expr_priv(expr);
238
239 return nft_counter_do_init(tb, priv);
240 }
241
nft_counter_destroy(const struct nft_ctx * ctx,const struct nft_expr * expr)242 static void nft_counter_destroy(const struct nft_ctx *ctx,
243 const struct nft_expr *expr)
244 {
245 struct nft_counter_percpu_priv *priv = nft_expr_priv(expr);
246
247 nft_counter_do_destroy(priv);
248 }
249
nft_counter_clone(struct nft_expr * dst,const struct nft_expr * src,gfp_t gfp)250 static int nft_counter_clone(struct nft_expr *dst, const struct nft_expr *src, gfp_t gfp)
251 {
252 struct nft_counter_percpu_priv *priv = nft_expr_priv(src);
253 struct nft_counter_percpu_priv *priv_clone = nft_expr_priv(dst);
254 struct nft_counter __percpu *cpu_stats;
255 struct nft_counter *this_cpu;
256 struct nft_counter_tot total;
257
258 nft_counter_fetch(priv, &total);
259
260 cpu_stats = alloc_percpu_gfp(struct nft_counter, gfp);
261 if (cpu_stats == NULL)
262 return -ENOMEM;
263
264 this_cpu = raw_cpu_ptr(cpu_stats);
265 u64_stats_set(&this_cpu->packets, total.packets);
266 u64_stats_set(&this_cpu->bytes, total.bytes);
267
268 priv_clone->counter = cpu_stats;
269 return 0;
270 }
271
nft_counter_offload(struct nft_offload_ctx * ctx,struct nft_flow_rule * flow,const struct nft_expr * expr)272 static int nft_counter_offload(struct nft_offload_ctx *ctx,
273 struct nft_flow_rule *flow,
274 const struct nft_expr *expr)
275 {
276 /* No specific offload action is needed, but report success. */
277 return 0;
278 }
279
nft_counter_offload_stats(struct nft_expr * expr,const struct flow_stats * stats)280 static void nft_counter_offload_stats(struct nft_expr *expr,
281 const struct flow_stats *stats)
282 {
283 struct nft_counter_percpu_priv *priv = nft_expr_priv(expr);
284 struct u64_stats_sync *nft_sync;
285 struct nft_counter *this_cpu;
286
287 local_bh_disable();
288 this_cpu = this_cpu_ptr(priv->counter);
289 nft_sync = this_cpu_ptr(&nft_counter_sync);
290
291 u64_stats_update_begin(nft_sync);
292 u64_stats_add(&this_cpu->packets, stats->pkts);
293 u64_stats_add(&this_cpu->bytes, stats->bytes);
294 u64_stats_update_end(nft_sync);
295 local_bh_enable();
296 }
297
nft_counter_init_seqcount(void)298 void nft_counter_init_seqcount(void)
299 {
300 int cpu;
301
302 for_each_possible_cpu(cpu)
303 u64_stats_init(per_cpu_ptr(&nft_counter_sync, cpu));
304 }
305
306 struct nft_expr_type nft_counter_type;
307 static const struct nft_expr_ops nft_counter_ops = {
308 .type = &nft_counter_type,
309 .size = NFT_EXPR_SIZE(sizeof(struct nft_counter_percpu_priv)),
310 .eval = nft_counter_eval,
311 .init = nft_counter_init,
312 .destroy = nft_counter_destroy,
313 .destroy_clone = nft_counter_destroy,
314 .dump = nft_counter_dump,
315 .clone = nft_counter_clone,
316 .reduce = NFT_REDUCE_READONLY,
317 .offload = nft_counter_offload,
318 .offload_stats = nft_counter_offload_stats,
319 };
320
321 struct nft_expr_type nft_counter_type __read_mostly = {
322 .name = "counter",
323 .ops = &nft_counter_ops,
324 .policy = nft_counter_policy,
325 .maxattr = NFTA_COUNTER_MAX,
326 .flags = NFT_EXPR_STATEFUL,
327 .owner = THIS_MODULE,
328 };
329