Merge tag 'for-6.1-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave...
[platform/kernel/linux-starfive.git] / net / sched / act_pedit.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * net/sched/act_pedit.c        Generic packet editor
4  *
5  * Authors:     Jamal Hadi Salim (2002-4)
6  */
7
8 #include <linux/types.h>
9 #include <linux/kernel.h>
10 #include <linux/string.h>
11 #include <linux/errno.h>
12 #include <linux/skbuff.h>
13 #include <linux/rtnetlink.h>
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/slab.h>
17 #include <net/netlink.h>
18 #include <net/pkt_sched.h>
19 #include <linux/tc_act/tc_pedit.h>
20 #include <net/tc_act/tc_pedit.h>
21 #include <uapi/linux/tc_act/tc_pedit.h>
22 #include <net/pkt_cls.h>
23
24 static struct tc_action_ops act_pedit_ops;
25
26 static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = {
27         [TCA_PEDIT_PARMS]       = { .len = sizeof(struct tc_pedit) },
28         [TCA_PEDIT_KEYS_EX]   = { .type = NLA_NESTED },
29 };
30
31 static const struct nla_policy pedit_key_ex_policy[TCA_PEDIT_KEY_EX_MAX + 1] = {
32         [TCA_PEDIT_KEY_EX_HTYPE]  = { .type = NLA_U16 },
33         [TCA_PEDIT_KEY_EX_CMD]    = { .type = NLA_U16 },
34 };
35
36 static struct tcf_pedit_key_ex *tcf_pedit_keys_ex_parse(struct nlattr *nla,
37                                                         u8 n)
38 {
39         struct tcf_pedit_key_ex *keys_ex;
40         struct tcf_pedit_key_ex *k;
41         const struct nlattr *ka;
42         int err = -EINVAL;
43         int rem;
44
45         if (!nla)
46                 return NULL;
47
48         keys_ex = kcalloc(n, sizeof(*k), GFP_KERNEL);
49         if (!keys_ex)
50                 return ERR_PTR(-ENOMEM);
51
52         k = keys_ex;
53
54         nla_for_each_nested(ka, nla, rem) {
55                 struct nlattr *tb[TCA_PEDIT_KEY_EX_MAX + 1];
56
57                 if (!n) {
58                         err = -EINVAL;
59                         goto err_out;
60                 }
61                 n--;
62
63                 if (nla_type(ka) != TCA_PEDIT_KEY_EX) {
64                         err = -EINVAL;
65                         goto err_out;
66                 }
67
68                 err = nla_parse_nested_deprecated(tb, TCA_PEDIT_KEY_EX_MAX,
69                                                   ka, pedit_key_ex_policy,
70                                                   NULL);
71                 if (err)
72                         goto err_out;
73
74                 if (!tb[TCA_PEDIT_KEY_EX_HTYPE] ||
75                     !tb[TCA_PEDIT_KEY_EX_CMD]) {
76                         err = -EINVAL;
77                         goto err_out;
78                 }
79
80                 k->htype = nla_get_u16(tb[TCA_PEDIT_KEY_EX_HTYPE]);
81                 k->cmd = nla_get_u16(tb[TCA_PEDIT_KEY_EX_CMD]);
82
83                 if (k->htype > TCA_PEDIT_HDR_TYPE_MAX ||
84                     k->cmd > TCA_PEDIT_CMD_MAX) {
85                         err = -EINVAL;
86                         goto err_out;
87                 }
88
89                 k++;
90         }
91
92         if (n) {
93                 err = -EINVAL;
94                 goto err_out;
95         }
96
97         return keys_ex;
98
99 err_out:
100         kfree(keys_ex);
101         return ERR_PTR(err);
102 }
103
104 static int tcf_pedit_key_ex_dump(struct sk_buff *skb,
105                                  struct tcf_pedit_key_ex *keys_ex, int n)
106 {
107         struct nlattr *keys_start = nla_nest_start_noflag(skb,
108                                                           TCA_PEDIT_KEYS_EX);
109
110         if (!keys_start)
111                 goto nla_failure;
112         for (; n > 0; n--) {
113                 struct nlattr *key_start;
114
115                 key_start = nla_nest_start_noflag(skb, TCA_PEDIT_KEY_EX);
116                 if (!key_start)
117                         goto nla_failure;
118
119                 if (nla_put_u16(skb, TCA_PEDIT_KEY_EX_HTYPE, keys_ex->htype) ||
120                     nla_put_u16(skb, TCA_PEDIT_KEY_EX_CMD, keys_ex->cmd))
121                         goto nla_failure;
122
123                 nla_nest_end(skb, key_start);
124
125                 keys_ex++;
126         }
127
128         nla_nest_end(skb, keys_start);
129
130         return 0;
131 nla_failure:
132         nla_nest_cancel(skb, keys_start);
133         return -EINVAL;
134 }
135
136 static int tcf_pedit_init(struct net *net, struct nlattr *nla,
137                           struct nlattr *est, struct tc_action **a,
138                           struct tcf_proto *tp, u32 flags,
139                           struct netlink_ext_ack *extack)
140 {
141         struct tc_action_net *tn = net_generic(net, act_pedit_ops.net_id);
142         bool bind = flags & TCA_ACT_FLAGS_BIND;
143         struct nlattr *tb[TCA_PEDIT_MAX + 1];
144         struct tcf_chain *goto_ch = NULL;
145         struct tc_pedit_key *keys = NULL;
146         struct tcf_pedit_key_ex *keys_ex;
147         struct tc_pedit *parm;
148         struct nlattr *pattr;
149         struct tcf_pedit *p;
150         int ret = 0, err;
151         int i, ksize;
152         u32 index;
153
154         if (!nla) {
155                 NL_SET_ERR_MSG_MOD(extack, "Pedit requires attributes to be passed");
156                 return -EINVAL;
157         }
158
159         err = nla_parse_nested_deprecated(tb, TCA_PEDIT_MAX, nla,
160                                           pedit_policy, NULL);
161         if (err < 0)
162                 return err;
163
164         pattr = tb[TCA_PEDIT_PARMS];
165         if (!pattr)
166                 pattr = tb[TCA_PEDIT_PARMS_EX];
167         if (!pattr) {
168                 NL_SET_ERR_MSG_MOD(extack, "Missing required TCA_PEDIT_PARMS or TCA_PEDIT_PARMS_EX pedit attribute");
169                 return -EINVAL;
170         }
171
172         parm = nla_data(pattr);
173         if (!parm->nkeys) {
174                 NL_SET_ERR_MSG_MOD(extack, "Pedit requires keys to be passed");
175                 return -EINVAL;
176         }
177         ksize = parm->nkeys * sizeof(struct tc_pedit_key);
178         if (nla_len(pattr) < sizeof(*parm) + ksize) {
179                 NL_SET_ERR_MSG_ATTR(extack, pattr, "Length of TCA_PEDIT_PARMS or TCA_PEDIT_PARMS_EX pedit attribute is invalid");
180                 return -EINVAL;
181         }
182
183         keys_ex = tcf_pedit_keys_ex_parse(tb[TCA_PEDIT_KEYS_EX], parm->nkeys);
184         if (IS_ERR(keys_ex))
185                 return PTR_ERR(keys_ex);
186
187         index = parm->index;
188         err = tcf_idr_check_alloc(tn, &index, a, bind);
189         if (!err) {
190                 ret = tcf_idr_create(tn, index, est, a,
191                                      &act_pedit_ops, bind, false, flags);
192                 if (ret) {
193                         tcf_idr_cleanup(tn, index);
194                         goto out_free;
195                 }
196                 ret = ACT_P_CREATED;
197         } else if (err > 0) {
198                 if (bind)
199                         goto out_free;
200                 if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
201                         ret = -EEXIST;
202                         goto out_release;
203                 }
204         } else {
205                 ret = err;
206                 goto out_free;
207         }
208
209         err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
210         if (err < 0) {
211                 ret = err;
212                 goto out_release;
213         }
214         p = to_pedit(*a);
215         spin_lock_bh(&p->tcf_lock);
216
217         if (ret == ACT_P_CREATED ||
218             (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys)) {
219                 keys = kmalloc(ksize, GFP_ATOMIC);
220                 if (!keys) {
221                         spin_unlock_bh(&p->tcf_lock);
222                         ret = -ENOMEM;
223                         goto put_chain;
224                 }
225                 kfree(p->tcfp_keys);
226                 p->tcfp_keys = keys;
227                 p->tcfp_nkeys = parm->nkeys;
228         }
229         memcpy(p->tcfp_keys, parm->keys, ksize);
230         p->tcfp_off_max_hint = 0;
231         for (i = 0; i < p->tcfp_nkeys; ++i) {
232                 u32 cur = p->tcfp_keys[i].off;
233
234                 /* sanitize the shift value for any later use */
235                 p->tcfp_keys[i].shift = min_t(size_t, BITS_PER_TYPE(int) - 1,
236                                               p->tcfp_keys[i].shift);
237
238                 /* The AT option can read a single byte, we can bound the actual
239                  * value with uchar max.
240                  */
241                 cur += (0xff & p->tcfp_keys[i].offmask) >> p->tcfp_keys[i].shift;
242
243                 /* Each key touches 4 bytes starting from the computed offset */
244                 p->tcfp_off_max_hint = max(p->tcfp_off_max_hint, cur + 4);
245         }
246
247         p->tcfp_flags = parm->flags;
248         goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
249
250         kfree(p->tcfp_keys_ex);
251         p->tcfp_keys_ex = keys_ex;
252
253         spin_unlock_bh(&p->tcf_lock);
254         if (goto_ch)
255                 tcf_chain_put_by_act(goto_ch);
256         return ret;
257
258 put_chain:
259         if (goto_ch)
260                 tcf_chain_put_by_act(goto_ch);
261 out_release:
262         tcf_idr_release(*a, bind);
263 out_free:
264         kfree(keys_ex);
265         return ret;
266
267 }
268
269 static void tcf_pedit_cleanup(struct tc_action *a)
270 {
271         struct tcf_pedit *p = to_pedit(a);
272         struct tc_pedit_key *keys = p->tcfp_keys;
273
274         kfree(keys);
275         kfree(p->tcfp_keys_ex);
276 }
277
278 static bool offset_valid(struct sk_buff *skb, int offset)
279 {
280         if (offset > 0 && offset > skb->len)
281                 return false;
282
283         if  (offset < 0 && -offset > skb_headroom(skb))
284                 return false;
285
286         return true;
287 }
288
289 static int pedit_skb_hdr_offset(struct sk_buff *skb,
290                                 enum pedit_header_type htype, int *hoffset)
291 {
292         int ret = -EINVAL;
293
294         switch (htype) {
295         case TCA_PEDIT_KEY_EX_HDR_TYPE_ETH:
296                 if (skb_mac_header_was_set(skb)) {
297                         *hoffset = skb_mac_offset(skb);
298                         ret = 0;
299                 }
300                 break;
301         case TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK:
302         case TCA_PEDIT_KEY_EX_HDR_TYPE_IP4:
303         case TCA_PEDIT_KEY_EX_HDR_TYPE_IP6:
304                 *hoffset = skb_network_offset(skb);
305                 ret = 0;
306                 break;
307         case TCA_PEDIT_KEY_EX_HDR_TYPE_TCP:
308         case TCA_PEDIT_KEY_EX_HDR_TYPE_UDP:
309                 if (skb_transport_header_was_set(skb)) {
310                         *hoffset = skb_transport_offset(skb);
311                         ret = 0;
312                 }
313                 break;
314         default:
315                 ret = -EINVAL;
316                 break;
317         }
318
319         return ret;
320 }
321
322 static int tcf_pedit_act(struct sk_buff *skb, const struct tc_action *a,
323                          struct tcf_result *res)
324 {
325         struct tcf_pedit *p = to_pedit(a);
326         u32 max_offset;
327         int i;
328
329         spin_lock(&p->tcf_lock);
330
331         max_offset = (skb_transport_header_was_set(skb) ?
332                       skb_transport_offset(skb) :
333                       skb_network_offset(skb)) +
334                      p->tcfp_off_max_hint;
335         if (skb_ensure_writable(skb, min(skb->len, max_offset)))
336                 goto unlock;
337
338         tcf_lastuse_update(&p->tcf_tm);
339
340         if (p->tcfp_nkeys > 0) {
341                 struct tc_pedit_key *tkey = p->tcfp_keys;
342                 struct tcf_pedit_key_ex *tkey_ex = p->tcfp_keys_ex;
343                 enum pedit_header_type htype =
344                         TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK;
345                 enum pedit_cmd cmd = TCA_PEDIT_KEY_EX_CMD_SET;
346
347                 for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
348                         u32 *ptr, hdata;
349                         int offset = tkey->off;
350                         int hoffset;
351                         u32 val;
352                         int rc;
353
354                         if (tkey_ex) {
355                                 htype = tkey_ex->htype;
356                                 cmd = tkey_ex->cmd;
357
358                                 tkey_ex++;
359                         }
360
361                         rc = pedit_skb_hdr_offset(skb, htype, &hoffset);
362                         if (rc) {
363                                 pr_info("tc action pedit bad header type specified (0x%x)\n",
364                                         htype);
365                                 goto bad;
366                         }
367
368                         if (tkey->offmask) {
369                                 u8 *d, _d;
370
371                                 if (!offset_valid(skb, hoffset + tkey->at)) {
372                                         pr_info("tc action pedit 'at' offset %d out of bounds\n",
373                                                 hoffset + tkey->at);
374                                         goto bad;
375                                 }
376                                 d = skb_header_pointer(skb, hoffset + tkey->at,
377                                                        sizeof(_d), &_d);
378                                 if (!d)
379                                         goto bad;
380                                 offset += (*d & tkey->offmask) >> tkey->shift;
381                         }
382
383                         if (offset % 4) {
384                                 pr_info("tc action pedit offset must be on 32 bit boundaries\n");
385                                 goto bad;
386                         }
387
388                         if (!offset_valid(skb, hoffset + offset)) {
389                                 pr_info("tc action pedit offset %d out of bounds\n",
390                                         hoffset + offset);
391                                 goto bad;
392                         }
393
394                         ptr = skb_header_pointer(skb, hoffset + offset,
395                                                  sizeof(hdata), &hdata);
396                         if (!ptr)
397                                 goto bad;
398                         /* just do it, baby */
399                         switch (cmd) {
400                         case TCA_PEDIT_KEY_EX_CMD_SET:
401                                 val = tkey->val;
402                                 break;
403                         case TCA_PEDIT_KEY_EX_CMD_ADD:
404                                 val = (*ptr + tkey->val) & ~tkey->mask;
405                                 break;
406                         default:
407                                 pr_info("tc action pedit bad command (%d)\n",
408                                         cmd);
409                                 goto bad;
410                         }
411
412                         *ptr = ((*ptr & tkey->mask) ^ val);
413                         if (ptr == &hdata)
414                                 skb_store_bits(skb, hoffset + offset, ptr, 4);
415                 }
416
417                 goto done;
418         } else {
419                 WARN(1, "pedit BUG: index %d\n", p->tcf_index);
420         }
421
422 bad:
423         p->tcf_qstats.overlimits++;
424 done:
425         bstats_update(&p->tcf_bstats, skb);
426 unlock:
427         spin_unlock(&p->tcf_lock);
428         return p->tcf_action;
429 }
430
431 static void tcf_pedit_stats_update(struct tc_action *a, u64 bytes, u64 packets,
432                                    u64 drops, u64 lastuse, bool hw)
433 {
434         struct tcf_pedit *d = to_pedit(a);
435         struct tcf_t *tm = &d->tcf_tm;
436
437         tcf_action_update_stats(a, bytes, packets, drops, hw);
438         tm->lastuse = max_t(u64, tm->lastuse, lastuse);
439 }
440
441 static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,
442                           int bind, int ref)
443 {
444         unsigned char *b = skb_tail_pointer(skb);
445         struct tcf_pedit *p = to_pedit(a);
446         struct tc_pedit *opt;
447         struct tcf_t t;
448         int s;
449
450         s = struct_size(opt, keys, p->tcfp_nkeys);
451
452         /* netlink spinlocks held above us - must use ATOMIC */
453         opt = kzalloc(s, GFP_ATOMIC);
454         if (unlikely(!opt))
455                 return -ENOBUFS;
456
457         spin_lock_bh(&p->tcf_lock);
458         memcpy(opt->keys, p->tcfp_keys, flex_array_size(opt, keys, p->tcfp_nkeys));
459         opt->index = p->tcf_index;
460         opt->nkeys = p->tcfp_nkeys;
461         opt->flags = p->tcfp_flags;
462         opt->action = p->tcf_action;
463         opt->refcnt = refcount_read(&p->tcf_refcnt) - ref;
464         opt->bindcnt = atomic_read(&p->tcf_bindcnt) - bind;
465
466         if (p->tcfp_keys_ex) {
467                 if (tcf_pedit_key_ex_dump(skb,
468                                           p->tcfp_keys_ex,
469                                           p->tcfp_nkeys))
470                         goto nla_put_failure;
471
472                 if (nla_put(skb, TCA_PEDIT_PARMS_EX, s, opt))
473                         goto nla_put_failure;
474         } else {
475                 if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
476                         goto nla_put_failure;
477         }
478
479         tcf_tm_dump(&t, &p->tcf_tm);
480         if (nla_put_64bit(skb, TCA_PEDIT_TM, sizeof(t), &t, TCA_PEDIT_PAD))
481                 goto nla_put_failure;
482         spin_unlock_bh(&p->tcf_lock);
483
484         kfree(opt);
485         return skb->len;
486
487 nla_put_failure:
488         spin_unlock_bh(&p->tcf_lock);
489         nlmsg_trim(skb, b);
490         kfree(opt);
491         return -1;
492 }
493
494 static int tcf_pedit_offload_act_setup(struct tc_action *act, void *entry_data,
495                                        u32 *index_inc, bool bind,
496                                        struct netlink_ext_ack *extack)
497 {
498         if (bind) {
499                 struct flow_action_entry *entry = entry_data;
500                 int k;
501
502                 for (k = 0; k < tcf_pedit_nkeys(act); k++) {
503                         switch (tcf_pedit_cmd(act, k)) {
504                         case TCA_PEDIT_KEY_EX_CMD_SET:
505                                 entry->id = FLOW_ACTION_MANGLE;
506                                 break;
507                         case TCA_PEDIT_KEY_EX_CMD_ADD:
508                                 entry->id = FLOW_ACTION_ADD;
509                                 break;
510                         default:
511                                 NL_SET_ERR_MSG_MOD(extack, "Unsupported pedit command offload");
512                                 return -EOPNOTSUPP;
513                         }
514                         entry->mangle.htype = tcf_pedit_htype(act, k);
515                         entry->mangle.mask = tcf_pedit_mask(act, k);
516                         entry->mangle.val = tcf_pedit_val(act, k);
517                         entry->mangle.offset = tcf_pedit_offset(act, k);
518                         entry->hw_stats = tc_act_hw_stats(act->hw_stats);
519                         entry++;
520                 }
521                 *index_inc = k;
522         } else {
523                 return -EOPNOTSUPP;
524         }
525
526         return 0;
527 }
528
529 static struct tc_action_ops act_pedit_ops = {
530         .kind           =       "pedit",
531         .id             =       TCA_ID_PEDIT,
532         .owner          =       THIS_MODULE,
533         .act            =       tcf_pedit_act,
534         .stats_update   =       tcf_pedit_stats_update,
535         .dump           =       tcf_pedit_dump,
536         .cleanup        =       tcf_pedit_cleanup,
537         .init           =       tcf_pedit_init,
538         .offload_act_setup =    tcf_pedit_offload_act_setup,
539         .size           =       sizeof(struct tcf_pedit),
540 };
541
542 static __net_init int pedit_init_net(struct net *net)
543 {
544         struct tc_action_net *tn = net_generic(net, act_pedit_ops.net_id);
545
546         return tc_action_net_init(net, tn, &act_pedit_ops);
547 }
548
549 static void __net_exit pedit_exit_net(struct list_head *net_list)
550 {
551         tc_action_net_exit(net_list, act_pedit_ops.net_id);
552 }
553
554 static struct pernet_operations pedit_net_ops = {
555         .init = pedit_init_net,
556         .exit_batch = pedit_exit_net,
557         .id   = &act_pedit_ops.net_id,
558         .size = sizeof(struct tc_action_net),
559 };
560
561 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
562 MODULE_DESCRIPTION("Generic Packet Editor actions");
563 MODULE_LICENSE("GPL");
564
565 static int __init pedit_init_module(void)
566 {
567         return tcf_register_action(&act_pedit_ops, &pedit_net_ops);
568 }
569
570 static void __exit pedit_cleanup_module(void)
571 {
572         tcf_unregister_action(&act_pedit_ops, &pedit_net_ops);
573 }
574
575 module_init(pedit_init_module);
576 module_exit(pedit_cleanup_module);