xref: /linux/net/sched/act_vlan.c (revision 07fdad3a93756b872da7b53647715c48d0f4a2d0)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (c) 2014 Jiri Pirko <jiri@resnulli.us>
4  */
5 
6 #include <linux/module.h>
7 #include <linux/init.h>
8 #include <linux/kernel.h>
9 #include <linux/skbuff.h>
10 #include <linux/rtnetlink.h>
11 #include <linux/if_vlan.h>
12 #include <net/netlink.h>
13 #include <net/pkt_sched.h>
14 #include <net/pkt_cls.h>
15 #include <net/tc_wrapper.h>
16 
17 #include <linux/tc_act/tc_vlan.h>
18 #include <net/tc_act/tc_vlan.h>
19 
20 static struct tc_action_ops act_vlan_ops;
21 
22 TC_INDIRECT_SCOPE int tcf_vlan_act(struct sk_buff *skb,
23 				   const struct tc_action *a,
24 				   struct tcf_result *res)
25 {
26 	struct tcf_vlan *v = to_vlan(a);
27 	struct tcf_vlan_params *p;
28 	int err;
29 	u16 tci;
30 
31 	tcf_lastuse_update(&v->tcf_tm);
32 	tcf_action_update_bstats(&v->common, skb);
33 
34 	/* Ensure 'data' points at mac_header prior calling vlan manipulating
35 	 * functions.
36 	 */
37 	if (skb_at_tc_ingress(skb))
38 		skb_push_rcsum(skb, skb->mac_len);
39 
40 	p = rcu_dereference_bh(v->vlan_p);
41 
42 	switch (p->tcfv_action) {
43 	case TCA_VLAN_ACT_POP:
44 		err = skb_vlan_pop(skb);
45 		if (err)
46 			goto drop;
47 		break;
48 	case TCA_VLAN_ACT_PUSH:
49 		err = skb_vlan_push(skb, p->tcfv_push_proto, p->tcfv_push_vid |
50 				    (p->tcfv_push_prio << VLAN_PRIO_SHIFT));
51 		if (err)
52 			goto drop;
53 		break;
54 	case TCA_VLAN_ACT_MODIFY:
55 		/* No-op if no vlan tag (either hw-accel or in-payload) */
56 		if (!skb_vlan_tagged(skb))
57 			goto out;
58 		/* extract existing tag (and guarantee no hw-accel tag) */
59 		if (skb_vlan_tag_present(skb)) {
60 			tci = skb_vlan_tag_get(skb);
61 			__vlan_hwaccel_clear_tag(skb);
62 		} else {
63 			/* in-payload vlan tag, pop it */
64 			err = __skb_vlan_pop(skb, &tci);
65 			if (err)
66 				goto drop;
67 		}
68 		/* replace the vid */
69 		tci = (tci & ~VLAN_VID_MASK) | p->tcfv_push_vid;
70 		/* replace prio bits, if tcfv_push_prio specified */
71 		if (p->tcfv_push_prio_exists) {
72 			tci &= ~VLAN_PRIO_MASK;
73 			tci |= p->tcfv_push_prio << VLAN_PRIO_SHIFT;
74 		}
75 		/* put updated tci as hwaccel tag */
76 		__vlan_hwaccel_put_tag(skb, p->tcfv_push_proto, tci);
77 		break;
78 	case TCA_VLAN_ACT_POP_ETH:
79 		err = skb_eth_pop(skb);
80 		if (err)
81 			goto drop;
82 		break;
83 	case TCA_VLAN_ACT_PUSH_ETH:
84 		err = skb_eth_push(skb, p->tcfv_push_dst, p->tcfv_push_src);
85 		if (err)
86 			goto drop;
87 		break;
88 	default:
89 		BUG();
90 	}
91 
92 out:
93 	if (skb_at_tc_ingress(skb))
94 		skb_pull_rcsum(skb, skb->mac_len);
95 
96 	skb_reset_mac_len(skb);
97 	return p->action;
98 
99 drop:
100 	tcf_action_inc_drop_qstats(&v->common);
101 	return TC_ACT_SHOT;
102 }
103 
104 static const struct nla_policy vlan_policy[TCA_VLAN_MAX + 1] = {
105 	[TCA_VLAN_UNSPEC]		= { .strict_start_type = TCA_VLAN_PUSH_ETH_DST },
106 	[TCA_VLAN_PARMS]		= { .len = sizeof(struct tc_vlan) },
107 	[TCA_VLAN_PUSH_VLAN_ID]		= { .type = NLA_U16 },
108 	[TCA_VLAN_PUSH_VLAN_PROTOCOL]	= { .type = NLA_U16 },
109 	[TCA_VLAN_PUSH_VLAN_PRIORITY]	= { .type = NLA_U8 },
110 	[TCA_VLAN_PUSH_ETH_DST]		= NLA_POLICY_ETH_ADDR,
111 	[TCA_VLAN_PUSH_ETH_SRC]		= NLA_POLICY_ETH_ADDR,
112 };
113 
114 static int tcf_vlan_init(struct net *net, struct nlattr *nla,
115 			 struct nlattr *est, struct tc_action **a,
116 			 struct tcf_proto *tp, u32 flags,
117 			 struct netlink_ext_ack *extack)
118 {
119 	struct tc_action_net *tn = net_generic(net, act_vlan_ops.net_id);
120 	bool bind = flags & TCA_ACT_FLAGS_BIND;
121 	struct nlattr *tb[TCA_VLAN_MAX + 1];
122 	struct tcf_chain *goto_ch = NULL;
123 	bool push_prio_exists = false;
124 	struct tcf_vlan_params *p;
125 	struct tc_vlan *parm;
126 	struct tcf_vlan *v;
127 	int action;
128 	u16 push_vid = 0;
129 	__be16 push_proto = 0;
130 	u8 push_prio = 0;
131 	bool exists = false;
132 	int ret = 0, err;
133 	u32 index;
134 
135 	if (!nla)
136 		return -EINVAL;
137 
138 	err = nla_parse_nested_deprecated(tb, TCA_VLAN_MAX, nla, vlan_policy,
139 					  NULL);
140 	if (err < 0)
141 		return err;
142 
143 	if (!tb[TCA_VLAN_PARMS])
144 		return -EINVAL;
145 	parm = nla_data(tb[TCA_VLAN_PARMS]);
146 	index = parm->index;
147 	err = tcf_idr_check_alloc(tn, &index, a, bind);
148 	if (err < 0)
149 		return err;
150 	exists = err;
151 	if (exists && bind)
152 		return ACT_P_BOUND;
153 
154 	switch (parm->v_action) {
155 	case TCA_VLAN_ACT_POP:
156 		break;
157 	case TCA_VLAN_ACT_PUSH:
158 	case TCA_VLAN_ACT_MODIFY:
159 		if (!tb[TCA_VLAN_PUSH_VLAN_ID]) {
160 			if (exists)
161 				tcf_idr_release(*a, bind);
162 			else
163 				tcf_idr_cleanup(tn, index);
164 			return -EINVAL;
165 		}
166 		push_vid = nla_get_u16(tb[TCA_VLAN_PUSH_VLAN_ID]);
167 		if (push_vid >= VLAN_VID_MASK) {
168 			if (exists)
169 				tcf_idr_release(*a, bind);
170 			else
171 				tcf_idr_cleanup(tn, index);
172 			return -ERANGE;
173 		}
174 
175 		if (tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]) {
176 			push_proto = nla_get_be16(tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]);
177 			switch (push_proto) {
178 			case htons(ETH_P_8021Q):
179 			case htons(ETH_P_8021AD):
180 				break;
181 			default:
182 				if (exists)
183 					tcf_idr_release(*a, bind);
184 				else
185 					tcf_idr_cleanup(tn, index);
186 				return -EPROTONOSUPPORT;
187 			}
188 		} else {
189 			push_proto = htons(ETH_P_8021Q);
190 		}
191 
192 		push_prio_exists = !!tb[TCA_VLAN_PUSH_VLAN_PRIORITY];
193 		if (push_prio_exists)
194 			push_prio = nla_get_u8(tb[TCA_VLAN_PUSH_VLAN_PRIORITY]);
195 		break;
196 	case TCA_VLAN_ACT_POP_ETH:
197 		break;
198 	case TCA_VLAN_ACT_PUSH_ETH:
199 		if (!tb[TCA_VLAN_PUSH_ETH_DST] || !tb[TCA_VLAN_PUSH_ETH_SRC]) {
200 			if (exists)
201 				tcf_idr_release(*a, bind);
202 			else
203 				tcf_idr_cleanup(tn, index);
204 			return -EINVAL;
205 		}
206 		break;
207 	default:
208 		if (exists)
209 			tcf_idr_release(*a, bind);
210 		else
211 			tcf_idr_cleanup(tn, index);
212 		return -EINVAL;
213 	}
214 	action = parm->v_action;
215 
216 	if (!exists) {
217 		ret = tcf_idr_create_from_flags(tn, index, est, a,
218 						&act_vlan_ops, bind, flags);
219 		if (ret) {
220 			tcf_idr_cleanup(tn, index);
221 			return ret;
222 		}
223 
224 		ret = ACT_P_CREATED;
225 	} else if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
226 		tcf_idr_release(*a, bind);
227 		return -EEXIST;
228 	}
229 
230 	err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
231 	if (err < 0)
232 		goto release_idr;
233 
234 	v = to_vlan(*a);
235 
236 	p = kzalloc(sizeof(*p), GFP_KERNEL);
237 	if (!p) {
238 		err = -ENOMEM;
239 		goto put_chain;
240 	}
241 
242 	p->tcfv_action = action;
243 	p->tcfv_push_vid = push_vid;
244 	p->tcfv_push_prio = push_prio;
245 	p->tcfv_push_prio_exists = push_prio_exists || action == TCA_VLAN_ACT_PUSH;
246 	p->tcfv_push_proto = push_proto;
247 
248 	if (action == TCA_VLAN_ACT_PUSH_ETH) {
249 		nla_memcpy(&p->tcfv_push_dst, tb[TCA_VLAN_PUSH_ETH_DST],
250 			   ETH_ALEN);
251 		nla_memcpy(&p->tcfv_push_src, tb[TCA_VLAN_PUSH_ETH_SRC],
252 			   ETH_ALEN);
253 	}
254 
255 	p->action = parm->action;
256 	spin_lock_bh(&v->tcf_lock);
257 	goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
258 	p = rcu_replace_pointer(v->vlan_p, p, lockdep_is_held(&v->tcf_lock));
259 	spin_unlock_bh(&v->tcf_lock);
260 
261 	if (goto_ch)
262 		tcf_chain_put_by_act(goto_ch);
263 	if (p)
264 		kfree_rcu(p, rcu);
265 
266 	return ret;
267 put_chain:
268 	if (goto_ch)
269 		tcf_chain_put_by_act(goto_ch);
270 release_idr:
271 	tcf_idr_release(*a, bind);
272 	return err;
273 }
274 
275 static void tcf_vlan_cleanup(struct tc_action *a)
276 {
277 	struct tcf_vlan *v = to_vlan(a);
278 	struct tcf_vlan_params *p;
279 
280 	p = rcu_dereference_protected(v->vlan_p, 1);
281 	if (p)
282 		kfree_rcu(p, rcu);
283 }
284 
285 static int tcf_vlan_dump(struct sk_buff *skb, struct tc_action *a,
286 			 int bind, int ref)
287 {
288 	unsigned char *b = skb_tail_pointer(skb);
289 	struct tcf_vlan *v = to_vlan(a);
290 	struct tcf_vlan_params *p;
291 	struct tc_vlan opt = {
292 		.index    = v->tcf_index,
293 		.refcnt   = refcount_read(&v->tcf_refcnt) - ref,
294 		.bindcnt  = atomic_read(&v->tcf_bindcnt) - bind,
295 	};
296 	struct tcf_t t;
297 
298 	rcu_read_lock();
299 	p = rcu_dereference(v->vlan_p);
300 	opt.action = p->action;
301 	opt.v_action = p->tcfv_action;
302 	if (nla_put(skb, TCA_VLAN_PARMS, sizeof(opt), &opt))
303 		goto nla_put_failure;
304 
305 	if ((p->tcfv_action == TCA_VLAN_ACT_PUSH ||
306 	     p->tcfv_action == TCA_VLAN_ACT_MODIFY) &&
307 	    (nla_put_u16(skb, TCA_VLAN_PUSH_VLAN_ID, p->tcfv_push_vid) ||
308 	     nla_put_be16(skb, TCA_VLAN_PUSH_VLAN_PROTOCOL,
309 			  p->tcfv_push_proto) ||
310 	     (p->tcfv_push_prio_exists &&
311 	      nla_put_u8(skb, TCA_VLAN_PUSH_VLAN_PRIORITY, p->tcfv_push_prio))))
312 		goto nla_put_failure;
313 
314 	if (p->tcfv_action == TCA_VLAN_ACT_PUSH_ETH) {
315 		if (nla_put(skb, TCA_VLAN_PUSH_ETH_DST, ETH_ALEN,
316 			    p->tcfv_push_dst))
317 			goto nla_put_failure;
318 		if (nla_put(skb, TCA_VLAN_PUSH_ETH_SRC, ETH_ALEN,
319 			    p->tcfv_push_src))
320 			goto nla_put_failure;
321 	}
322 
323 	tcf_tm_dump(&t, &v->tcf_tm);
324 	if (nla_put_64bit(skb, TCA_VLAN_TM, sizeof(t), &t, TCA_VLAN_PAD))
325 		goto nla_put_failure;
326 	rcu_read_unlock();
327 
328 	return skb->len;
329 
330 nla_put_failure:
331 	rcu_read_unlock();
332 	nlmsg_trim(skb, b);
333 	return -1;
334 }
335 
336 static void tcf_vlan_stats_update(struct tc_action *a, u64 bytes, u64 packets,
337 				  u64 drops, u64 lastuse, bool hw)
338 {
339 	struct tcf_vlan *v = to_vlan(a);
340 	struct tcf_t *tm = &v->tcf_tm;
341 
342 	tcf_action_update_stats(a, bytes, packets, drops, hw);
343 	tm->lastuse = max_t(u64, tm->lastuse, lastuse);
344 }
345 
346 static size_t tcf_vlan_get_fill_size(const struct tc_action *act)
347 {
348 	return nla_total_size(sizeof(struct tc_vlan))
349 		+ nla_total_size(sizeof(u16)) /* TCA_VLAN_PUSH_VLAN_ID */
350 		+ nla_total_size(sizeof(u16)) /* TCA_VLAN_PUSH_VLAN_PROTOCOL */
351 		+ nla_total_size(sizeof(u8)); /* TCA_VLAN_PUSH_VLAN_PRIORITY */
352 }
353 
354 static int tcf_vlan_offload_act_setup(struct tc_action *act, void *entry_data,
355 				      u32 *index_inc, bool bind,
356 				      struct netlink_ext_ack *extack)
357 {
358 	if (bind) {
359 		struct flow_action_entry *entry = entry_data;
360 
361 		switch (tcf_vlan_action(act)) {
362 		case TCA_VLAN_ACT_PUSH:
363 			entry->id = FLOW_ACTION_VLAN_PUSH;
364 			entry->vlan.vid = tcf_vlan_push_vid(act);
365 			entry->vlan.proto = tcf_vlan_push_proto(act);
366 			entry->vlan.prio = tcf_vlan_push_prio(act);
367 			break;
368 		case TCA_VLAN_ACT_POP:
369 			entry->id = FLOW_ACTION_VLAN_POP;
370 			break;
371 		case TCA_VLAN_ACT_MODIFY:
372 			entry->id = FLOW_ACTION_VLAN_MANGLE;
373 			entry->vlan.vid = tcf_vlan_push_vid(act);
374 			entry->vlan.proto = tcf_vlan_push_proto(act);
375 			entry->vlan.prio = tcf_vlan_push_prio(act);
376 			break;
377 		case TCA_VLAN_ACT_POP_ETH:
378 			entry->id = FLOW_ACTION_VLAN_POP_ETH;
379 			break;
380 		case TCA_VLAN_ACT_PUSH_ETH:
381 			entry->id = FLOW_ACTION_VLAN_PUSH_ETH;
382 			tcf_vlan_push_eth(entry->vlan_push_eth.src, entry->vlan_push_eth.dst, act);
383 			break;
384 		default:
385 			NL_SET_ERR_MSG_MOD(extack, "Unsupported vlan action mode offload");
386 			return -EOPNOTSUPP;
387 		}
388 		*index_inc = 1;
389 	} else {
390 		struct flow_offload_action *fl_action = entry_data;
391 
392 		switch (tcf_vlan_action(act)) {
393 		case TCA_VLAN_ACT_PUSH:
394 			fl_action->id = FLOW_ACTION_VLAN_PUSH;
395 			break;
396 		case TCA_VLAN_ACT_POP:
397 			fl_action->id = FLOW_ACTION_VLAN_POP;
398 			break;
399 		case TCA_VLAN_ACT_MODIFY:
400 			fl_action->id = FLOW_ACTION_VLAN_MANGLE;
401 			break;
402 		case TCA_VLAN_ACT_POP_ETH:
403 			fl_action->id = FLOW_ACTION_VLAN_POP_ETH;
404 			break;
405 		case TCA_VLAN_ACT_PUSH_ETH:
406 			fl_action->id = FLOW_ACTION_VLAN_PUSH_ETH;
407 			break;
408 		default:
409 			return -EOPNOTSUPP;
410 		}
411 	}
412 
413 	return 0;
414 }
415 
416 static struct tc_action_ops act_vlan_ops = {
417 	.kind		=	"vlan",
418 	.id		=	TCA_ID_VLAN,
419 	.owner		=	THIS_MODULE,
420 	.act		=	tcf_vlan_act,
421 	.dump		=	tcf_vlan_dump,
422 	.init		=	tcf_vlan_init,
423 	.cleanup	=	tcf_vlan_cleanup,
424 	.stats_update	=	tcf_vlan_stats_update,
425 	.get_fill_size	=	tcf_vlan_get_fill_size,
426 	.offload_act_setup =	tcf_vlan_offload_act_setup,
427 	.size		=	sizeof(struct tcf_vlan),
428 };
429 MODULE_ALIAS_NET_ACT("vlan");
430 
431 static __net_init int vlan_init_net(struct net *net)
432 {
433 	struct tc_action_net *tn = net_generic(net, act_vlan_ops.net_id);
434 
435 	return tc_action_net_init(net, tn, &act_vlan_ops);
436 }
437 
438 static void __net_exit vlan_exit_net(struct list_head *net_list)
439 {
440 	tc_action_net_exit(net_list, act_vlan_ops.net_id);
441 }
442 
443 static struct pernet_operations vlan_net_ops = {
444 	.init = vlan_init_net,
445 	.exit_batch = vlan_exit_net,
446 	.id   = &act_vlan_ops.net_id,
447 	.size = sizeof(struct tc_action_net),
448 };
449 
450 static int __init vlan_init_module(void)
451 {
452 	return tcf_register_action(&act_vlan_ops, &vlan_net_ops);
453 }
454 
455 static void __exit vlan_cleanup_module(void)
456 {
457 	tcf_unregister_action(&act_vlan_ops, &vlan_net_ops);
458 }
459 
460 module_init(vlan_init_module);
461 module_exit(vlan_cleanup_module);
462 
463 MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>");
464 MODULE_DESCRIPTION("vlan manipulation actions");
465 MODULE_LICENSE("GPL v2");
466