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