i40e: Fix unexpected MFS warning message
[platform/kernel/linux-starfive.git] / net / sched / cls_fw.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * net/sched/cls_fw.c   Classifier mapping ipchains' fwmark to traffic class.
4  *
5  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
6  *
7  * Changes:
8  * Karlis Peisenieks <karlis@mt.lv> : 990415 : fw_walk off by one
9  * Karlis Peisenieks <karlis@mt.lv> : 990415 : fw_delete killed all the filter (and kernel).
10  * Alex <alex@pilotsoft.com> : 2004xxyy: Added Action extension
11  */
12
13 #include <linux/module.h>
14 #include <linux/slab.h>
15 #include <linux/types.h>
16 #include <linux/kernel.h>
17 #include <linux/string.h>
18 #include <linux/errno.h>
19 #include <linux/skbuff.h>
20 #include <net/netlink.h>
21 #include <net/act_api.h>
22 #include <net/pkt_cls.h>
23 #include <net/sch_generic.h>
24 #include <net/tc_wrapper.h>
25
26 #define HTSIZE 256
27
28 struct fw_head {
29         u32                     mask;
30         struct fw_filter __rcu  *ht[HTSIZE];
31         struct rcu_head         rcu;
32 };
33
34 struct fw_filter {
35         struct fw_filter __rcu  *next;
36         u32                     id;
37         struct tcf_result       res;
38         int                     ifindex;
39         struct tcf_exts         exts;
40         struct tcf_proto        *tp;
41         struct rcu_work         rwork;
42 };
43
44 static u32 fw_hash(u32 handle)
45 {
46         handle ^= (handle >> 16);
47         handle ^= (handle >> 8);
48         return handle % HTSIZE;
49 }
50
51 TC_INDIRECT_SCOPE int fw_classify(struct sk_buff *skb,
52                                   const struct tcf_proto *tp,
53                                   struct tcf_result *res)
54 {
55         struct fw_head *head = rcu_dereference_bh(tp->root);
56         struct fw_filter *f;
57         int r;
58         u32 id = skb->mark;
59
60         if (head != NULL) {
61                 id &= head->mask;
62
63                 for (f = rcu_dereference_bh(head->ht[fw_hash(id)]); f;
64                      f = rcu_dereference_bh(f->next)) {
65                         if (f->id == id) {
66                                 *res = f->res;
67                                 if (!tcf_match_indev(skb, f->ifindex))
68                                         continue;
69                                 r = tcf_exts_exec(skb, &f->exts, res);
70                                 if (r < 0)
71                                         continue;
72
73                                 return r;
74                         }
75                 }
76         } else {
77                 struct Qdisc *q = tcf_block_q(tp->chain->block);
78
79                 /* Old method: classify the packet using its skb mark. */
80                 if (id && (TC_H_MAJ(id) == 0 ||
81                            !(TC_H_MAJ(id ^ q->handle)))) {
82                         res->classid = id;
83                         res->class = 0;
84                         return 0;
85                 }
86         }
87
88         return -1;
89 }
90
91 static void *fw_get(struct tcf_proto *tp, u32 handle)
92 {
93         struct fw_head *head = rtnl_dereference(tp->root);
94         struct fw_filter *f;
95
96         if (head == NULL)
97                 return NULL;
98
99         f = rtnl_dereference(head->ht[fw_hash(handle)]);
100         for (; f; f = rtnl_dereference(f->next)) {
101                 if (f->id == handle)
102                         return f;
103         }
104         return NULL;
105 }
106
107 static int fw_init(struct tcf_proto *tp)
108 {
109         /* We don't allocate fw_head here, because in the old method
110          * we don't need it at all.
111          */
112         return 0;
113 }
114
115 static void __fw_delete_filter(struct fw_filter *f)
116 {
117         tcf_exts_destroy(&f->exts);
118         tcf_exts_put_net(&f->exts);
119         kfree(f);
120 }
121
122 static void fw_delete_filter_work(struct work_struct *work)
123 {
124         struct fw_filter *f = container_of(to_rcu_work(work),
125                                            struct fw_filter,
126                                            rwork);
127         rtnl_lock();
128         __fw_delete_filter(f);
129         rtnl_unlock();
130 }
131
132 static void fw_destroy(struct tcf_proto *tp, bool rtnl_held,
133                        struct netlink_ext_ack *extack)
134 {
135         struct fw_head *head = rtnl_dereference(tp->root);
136         struct fw_filter *f;
137         int h;
138
139         if (head == NULL)
140                 return;
141
142         for (h = 0; h < HTSIZE; h++) {
143                 while ((f = rtnl_dereference(head->ht[h])) != NULL) {
144                         RCU_INIT_POINTER(head->ht[h],
145                                          rtnl_dereference(f->next));
146                         tcf_unbind_filter(tp, &f->res);
147                         if (tcf_exts_get_net(&f->exts))
148                                 tcf_queue_work(&f->rwork, fw_delete_filter_work);
149                         else
150                                 __fw_delete_filter(f);
151                 }
152         }
153         kfree_rcu(head, rcu);
154 }
155
156 static int fw_delete(struct tcf_proto *tp, void *arg, bool *last,
157                      bool rtnl_held, struct netlink_ext_ack *extack)
158 {
159         struct fw_head *head = rtnl_dereference(tp->root);
160         struct fw_filter *f = arg;
161         struct fw_filter __rcu **fp;
162         struct fw_filter *pfp;
163         int ret = -EINVAL;
164         int h;
165
166         if (head == NULL || f == NULL)
167                 goto out;
168
169         fp = &head->ht[fw_hash(f->id)];
170
171         for (pfp = rtnl_dereference(*fp); pfp;
172              fp = &pfp->next, pfp = rtnl_dereference(*fp)) {
173                 if (pfp == f) {
174                         RCU_INIT_POINTER(*fp, rtnl_dereference(f->next));
175                         tcf_unbind_filter(tp, &f->res);
176                         tcf_exts_get_net(&f->exts);
177                         tcf_queue_work(&f->rwork, fw_delete_filter_work);
178                         ret = 0;
179                         break;
180                 }
181         }
182
183         *last = true;
184         for (h = 0; h < HTSIZE; h++) {
185                 if (rcu_access_pointer(head->ht[h])) {
186                         *last = false;
187                         break;
188                 }
189         }
190
191 out:
192         return ret;
193 }
194
195 static const struct nla_policy fw_policy[TCA_FW_MAX + 1] = {
196         [TCA_FW_CLASSID]        = { .type = NLA_U32 },
197         [TCA_FW_INDEV]          = { .type = NLA_STRING, .len = IFNAMSIZ },
198         [TCA_FW_MASK]           = { .type = NLA_U32 },
199 };
200
201 static int fw_set_parms(struct net *net, struct tcf_proto *tp,
202                         struct fw_filter *f, struct nlattr **tb,
203                         struct nlattr **tca, unsigned long base, u32 flags,
204                         struct netlink_ext_ack *extack)
205 {
206         struct fw_head *head = rtnl_dereference(tp->root);
207         u32 mask;
208         int err;
209
210         err = tcf_exts_validate(net, tp, tb, tca[TCA_RATE], &f->exts, flags,
211                                 extack);
212         if (err < 0)
213                 return err;
214
215         if (tb[TCA_FW_INDEV]) {
216                 int ret;
217                 ret = tcf_change_indev(net, tb[TCA_FW_INDEV], extack);
218                 if (ret < 0)
219                         return ret;
220                 f->ifindex = ret;
221         }
222
223         err = -EINVAL;
224         if (tb[TCA_FW_MASK]) {
225                 mask = nla_get_u32(tb[TCA_FW_MASK]);
226                 if (mask != head->mask)
227                         return err;
228         } else if (head->mask != 0xFFFFFFFF)
229                 return err;
230
231         if (tb[TCA_FW_CLASSID]) {
232                 f->res.classid = nla_get_u32(tb[TCA_FW_CLASSID]);
233                 tcf_bind_filter(tp, &f->res, base);
234         }
235
236         return 0;
237 }
238
239 static int fw_change(struct net *net, struct sk_buff *in_skb,
240                      struct tcf_proto *tp, unsigned long base,
241                      u32 handle, struct nlattr **tca, void **arg,
242                      u32 flags, struct netlink_ext_ack *extack)
243 {
244         struct fw_head *head = rtnl_dereference(tp->root);
245         struct fw_filter *f = *arg;
246         struct nlattr *opt = tca[TCA_OPTIONS];
247         struct nlattr *tb[TCA_FW_MAX + 1];
248         int err;
249
250         if (!opt)
251                 return handle ? -EINVAL : 0; /* Succeed if it is old method. */
252
253         err = nla_parse_nested_deprecated(tb, TCA_FW_MAX, opt, fw_policy,
254                                           NULL);
255         if (err < 0)
256                 return err;
257
258         if (f) {
259                 struct fw_filter *pfp, *fnew;
260                 struct fw_filter __rcu **fp;
261
262                 if (f->id != handle && handle)
263                         return -EINVAL;
264
265                 fnew = kzalloc(sizeof(struct fw_filter), GFP_KERNEL);
266                 if (!fnew)
267                         return -ENOBUFS;
268
269                 fnew->id = f->id;
270                 fnew->ifindex = f->ifindex;
271                 fnew->tp = f->tp;
272
273                 err = tcf_exts_init(&fnew->exts, net, TCA_FW_ACT,
274                                     TCA_FW_POLICE);
275                 if (err < 0) {
276                         kfree(fnew);
277                         return err;
278                 }
279
280                 err = fw_set_parms(net, tp, fnew, tb, tca, base, flags, extack);
281                 if (err < 0) {
282                         tcf_exts_destroy(&fnew->exts);
283                         kfree(fnew);
284                         return err;
285                 }
286
287                 fp = &head->ht[fw_hash(fnew->id)];
288                 for (pfp = rtnl_dereference(*fp); pfp;
289                      fp = &pfp->next, pfp = rtnl_dereference(*fp))
290                         if (pfp == f)
291                                 break;
292
293                 RCU_INIT_POINTER(fnew->next, rtnl_dereference(pfp->next));
294                 rcu_assign_pointer(*fp, fnew);
295                 tcf_unbind_filter(tp, &f->res);
296                 tcf_exts_get_net(&f->exts);
297                 tcf_queue_work(&f->rwork, fw_delete_filter_work);
298
299                 *arg = fnew;
300                 return err;
301         }
302
303         if (!handle)
304                 return -EINVAL;
305
306         if (!head) {
307                 u32 mask = 0xFFFFFFFF;
308                 if (tb[TCA_FW_MASK])
309                         mask = nla_get_u32(tb[TCA_FW_MASK]);
310
311                 head = kzalloc(sizeof(*head), GFP_KERNEL);
312                 if (!head)
313                         return -ENOBUFS;
314                 head->mask = mask;
315
316                 rcu_assign_pointer(tp->root, head);
317         }
318
319         f = kzalloc(sizeof(struct fw_filter), GFP_KERNEL);
320         if (f == NULL)
321                 return -ENOBUFS;
322
323         err = tcf_exts_init(&f->exts, net, TCA_FW_ACT, TCA_FW_POLICE);
324         if (err < 0)
325                 goto errout;
326         f->id = handle;
327         f->tp = tp;
328
329         err = fw_set_parms(net, tp, f, tb, tca, base, flags, extack);
330         if (err < 0)
331                 goto errout;
332
333         RCU_INIT_POINTER(f->next, head->ht[fw_hash(handle)]);
334         rcu_assign_pointer(head->ht[fw_hash(handle)], f);
335
336         *arg = f;
337         return 0;
338
339 errout:
340         tcf_exts_destroy(&f->exts);
341         kfree(f);
342         return err;
343 }
344
345 static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg,
346                     bool rtnl_held)
347 {
348         struct fw_head *head = rtnl_dereference(tp->root);
349         int h;
350
351         if (head == NULL)
352                 arg->stop = 1;
353
354         if (arg->stop)
355                 return;
356
357         for (h = 0; h < HTSIZE; h++) {
358                 struct fw_filter *f;
359
360                 for (f = rtnl_dereference(head->ht[h]); f;
361                      f = rtnl_dereference(f->next)) {
362                         if (!tc_cls_stats_dump(tp, arg, f))
363                                 return;
364                 }
365         }
366 }
367
368 static int fw_dump(struct net *net, struct tcf_proto *tp, void *fh,
369                    struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
370 {
371         struct fw_head *head = rtnl_dereference(tp->root);
372         struct fw_filter *f = fh;
373         struct nlattr *nest;
374
375         if (f == NULL)
376                 return skb->len;
377
378         t->tcm_handle = f->id;
379
380         if (!f->res.classid && !tcf_exts_has_actions(&f->exts))
381                 return skb->len;
382
383         nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
384         if (nest == NULL)
385                 goto nla_put_failure;
386
387         if (f->res.classid &&
388             nla_put_u32(skb, TCA_FW_CLASSID, f->res.classid))
389                 goto nla_put_failure;
390         if (f->ifindex) {
391                 struct net_device *dev;
392                 dev = __dev_get_by_index(net, f->ifindex);
393                 if (dev && nla_put_string(skb, TCA_FW_INDEV, dev->name))
394                         goto nla_put_failure;
395         }
396         if (head->mask != 0xFFFFFFFF &&
397             nla_put_u32(skb, TCA_FW_MASK, head->mask))
398                 goto nla_put_failure;
399
400         if (tcf_exts_dump(skb, &f->exts) < 0)
401                 goto nla_put_failure;
402
403         nla_nest_end(skb, nest);
404
405         if (tcf_exts_dump_stats(skb, &f->exts) < 0)
406                 goto nla_put_failure;
407
408         return skb->len;
409
410 nla_put_failure:
411         nla_nest_cancel(skb, nest);
412         return -1;
413 }
414
415 static void fw_bind_class(void *fh, u32 classid, unsigned long cl, void *q,
416                           unsigned long base)
417 {
418         struct fw_filter *f = fh;
419
420         tc_cls_bind_class(classid, cl, q, &f->res, base);
421 }
422
423 static struct tcf_proto_ops cls_fw_ops __read_mostly = {
424         .kind           =       "fw",
425         .classify       =       fw_classify,
426         .init           =       fw_init,
427         .destroy        =       fw_destroy,
428         .get            =       fw_get,
429         .change         =       fw_change,
430         .delete         =       fw_delete,
431         .walk           =       fw_walk,
432         .dump           =       fw_dump,
433         .bind_class     =       fw_bind_class,
434         .owner          =       THIS_MODULE,
435 };
436
437 static int __init init_fw(void)
438 {
439         return register_tcf_proto_ops(&cls_fw_ops);
440 }
441
442 static void __exit exit_fw(void)
443 {
444         unregister_tcf_proto_ops(&cls_fw_ops);
445 }
446
447 module_init(init_fw)
448 module_exit(exit_fw)
449 MODULE_LICENSE("GPL");