xref: /linux/net/sched/act_vlan.c (revision 1553a1c48281243359a9529a10ddb551f3b967ab)
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 action;
29 	int err;
30 	u16 tci;
31 
32 	tcf_lastuse_update(&v->tcf_tm);
33 	tcf_action_update_bstats(&v->common, skb);
34 
35 	/* Ensure 'data' points at mac_header prior calling vlan manipulating
36 	 * functions.
37 	 */
38 	if (skb_at_tc_ingress(skb))
39 		skb_push_rcsum(skb, skb->mac_len);
40 
41 	action = READ_ONCE(v->tcf_action);
42 
43 	p = rcu_dereference_bh(v->vlan_p);
44 
45 	switch (p->tcfv_action) {
46 	case TCA_VLAN_ACT_POP:
47 		err = skb_vlan_pop(skb);
48 		if (err)
49 			goto drop;
50 		break;
51 	case TCA_VLAN_ACT_PUSH:
52 		err = skb_vlan_push(skb, p->tcfv_push_proto, p->tcfv_push_vid |
53 				    (p->tcfv_push_prio << VLAN_PRIO_SHIFT));
54 		if (err)
55 			goto drop;
56 		break;
57 	case TCA_VLAN_ACT_MODIFY:
58 		/* No-op if no vlan tag (either hw-accel or in-payload) */
59 		if (!skb_vlan_tagged(skb))
60 			goto out;
61 		/* extract existing tag (and guarantee no hw-accel tag) */
62 		if (skb_vlan_tag_present(skb)) {
63 			tci = skb_vlan_tag_get(skb);
64 			__vlan_hwaccel_clear_tag(skb);
65 		} else {
66 			/* in-payload vlan tag, pop it */
67 			err = __skb_vlan_pop(skb, &tci);
68 			if (err)
69 				goto drop;
70 		}
71 		/* replace the vid */
72 		tci = (tci & ~VLAN_VID_MASK) | p->tcfv_push_vid;
73 		/* replace prio bits, if tcfv_push_prio specified */
74 		if (p->tcfv_push_prio_exists) {
75 			tci &= ~VLAN_PRIO_MASK;
76 			tci |= p->tcfv_push_prio << VLAN_PRIO_SHIFT;
77 		}
78 		/* put updated tci as hwaccel tag */
79 		__vlan_hwaccel_put_tag(skb, p->tcfv_push_proto, tci);
80 		break;
81 	case TCA_VLAN_ACT_POP_ETH:
82 		err = skb_eth_pop(skb);
83 		if (err)
84 			goto drop;
85 		break;
86 	case TCA_VLAN_ACT_PUSH_ETH:
87 		err = skb_eth_push(skb, p->tcfv_push_dst, p->tcfv_push_src);
88 		if (err)
89 			goto drop;
90 		break;
91 	default:
92 		BUG();
93 	}
94 
95 out:
96 	if (skb_at_tc_ingress(skb))
97 		skb_pull_rcsum(skb, skb->mac_len);
98 
99 	return action;
100 
101 drop:
102 	tcf_action_inc_drop_qstats(&v->common);
103 	return TC_ACT_SHOT;
104 }
105 
106 static const struct nla_policy vlan_policy[TCA_VLAN_MAX + 1] = {
107 	[TCA_VLAN_UNSPEC]		= { .strict_start_type = TCA_VLAN_PUSH_ETH_DST },
108 	[TCA_VLAN_PARMS]		= { .len = sizeof(struct tc_vlan) },
109 	[TCA_VLAN_PUSH_VLAN_ID]		= { .type = NLA_U16 },
110 	[TCA_VLAN_PUSH_VLAN_PROTOCOL]	= { .type = NLA_U16 },
111 	[TCA_VLAN_PUSH_VLAN_PRIORITY]	= { .type = NLA_U8 },
112 	[TCA_VLAN_PUSH_ETH_DST]		= NLA_POLICY_ETH_ADDR,
113 	[TCA_VLAN_PUSH_ETH_SRC]		= NLA_POLICY_ETH_ADDR,
114 };
115 
116 static int tcf_vlan_init(struct net *net, struct nlattr *nla,
117 			 struct nlattr *est, struct tc_action **a,
118 			 struct tcf_proto *tp, u32 flags,
119 			 struct netlink_ext_ack *extack)
120 {
121 	struct tc_action_net *tn = net_generic(net, act_vlan_ops.net_id);
122 	bool bind = flags & TCA_ACT_FLAGS_BIND;
123 	struct nlattr *tb[TCA_VLAN_MAX + 1];
124 	struct tcf_chain *goto_ch = NULL;
125 	bool push_prio_exists = false;
126 	struct tcf_vlan_params *p;
127 	struct tc_vlan *parm;
128 	struct tcf_vlan *v;
129 	int action;
130 	u16 push_vid = 0;
131 	__be16 push_proto = 0;
132 	u8 push_prio = 0;
133 	bool exists = false;
134 	int ret = 0, err;
135 	u32 index;
136 
137 	if (!nla)
138 		return -EINVAL;
139 
140 	err = nla_parse_nested_deprecated(tb, TCA_VLAN_MAX, nla, vlan_policy,
141 					  NULL);
142 	if (err < 0)
143 		return err;
144 
145 	if (!tb[TCA_VLAN_PARMS])
146 		return -EINVAL;
147 	parm = nla_data(tb[TCA_VLAN_PARMS]);
148 	index = parm->index;
149 	err = tcf_idr_check_alloc(tn, &index, a, bind);
150 	if (err < 0)
151 		return err;
152 	exists = err;
153 	if (exists && bind)
154 		return ACT_P_BOUND;
155 
156 	switch (parm->v_action) {
157 	case TCA_VLAN_ACT_POP:
158 		break;
159 	case TCA_VLAN_ACT_PUSH:
160 	case TCA_VLAN_ACT_MODIFY:
161 		if (!tb[TCA_VLAN_PUSH_VLAN_ID]) {
162 			if (exists)
163 				tcf_idr_release(*a, bind);
164 			else
165 				tcf_idr_cleanup(tn, index);
166 			return -EINVAL;
167 		}
168 		push_vid = nla_get_u16(tb[TCA_VLAN_PUSH_VLAN_ID]);
169 		if (push_vid >= VLAN_VID_MASK) {
170 			if (exists)
171 				tcf_idr_release(*a, bind);
172 			else
173 				tcf_idr_cleanup(tn, index);
174 			return -ERANGE;
175 		}
176 
177 		if (tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]) {
178 			push_proto = nla_get_be16(tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]);
179 			switch (push_proto) {
180 			case htons(ETH_P_8021Q):
181 			case htons(ETH_P_8021AD):
182 				break;
183 			default:
184 				if (exists)
185 					tcf_idr_release(*a, bind);
186 				else
187 					tcf_idr_cleanup(tn, index);
188 				return -EPROTONOSUPPORT;
189 			}
190 		} else {
191 			push_proto = htons(ETH_P_8021Q);
192 		}
193 
194 		push_prio_exists = !!tb[TCA_VLAN_PUSH_VLAN_PRIORITY];
195 		if (push_prio_exists)
196 			push_prio = nla_get_u8(tb[TCA_VLAN_PUSH_VLAN_PRIORITY]);
197 		break;
198 	case TCA_VLAN_ACT_POP_ETH:
199 		break;
200 	case TCA_VLAN_ACT_PUSH_ETH:
201 		if (!tb[TCA_VLAN_PUSH_ETH_DST] || !tb[TCA_VLAN_PUSH_ETH_SRC]) {
202 			if (exists)
203 				tcf_idr_release(*a, bind);
204 			else
205 				tcf_idr_cleanup(tn, index);
206 			return -EINVAL;
207 		}
208 		break;
209 	default:
210 		if (exists)
211 			tcf_idr_release(*a, bind);
212 		else
213 			tcf_idr_cleanup(tn, index);
214 		return -EINVAL;
215 	}
216 	action = parm->v_action;
217 
218 	if (!exists) {
219 		ret = tcf_idr_create_from_flags(tn, index, est, a,
220 						&act_vlan_ops, bind, flags);
221 		if (ret) {
222 			tcf_idr_cleanup(tn, index);
223 			return ret;
224 		}
225 
226 		ret = ACT_P_CREATED;
227 	} else if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
228 		tcf_idr_release(*a, bind);
229 		return -EEXIST;
230 	}
231 
232 	err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
233 	if (err < 0)
234 		goto release_idr;
235 
236 	v = to_vlan(*a);
237 
238 	p = kzalloc(sizeof(*p), GFP_KERNEL);
239 	if (!p) {
240 		err = -ENOMEM;
241 		goto put_chain;
242 	}
243 
244 	p->tcfv_action = action;
245 	p->tcfv_push_vid = push_vid;
246 	p->tcfv_push_prio = push_prio;
247 	p->tcfv_push_prio_exists = push_prio_exists || action == TCA_VLAN_ACT_PUSH;
248 	p->tcfv_push_proto = push_proto;
249 
250 	if (action == TCA_VLAN_ACT_PUSH_ETH) {
251 		nla_memcpy(&p->tcfv_push_dst, tb[TCA_VLAN_PUSH_ETH_DST],
252 			   ETH_ALEN);
253 		nla_memcpy(&p->tcfv_push_src, tb[TCA_VLAN_PUSH_ETH_SRC],
254 			   ETH_ALEN);
255 	}
256 
257 	spin_lock_bh(&v->tcf_lock);
258 	goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
259 	p = rcu_replace_pointer(v->vlan_p, p, lockdep_is_held(&v->tcf_lock));
260 	spin_unlock_bh(&v->tcf_lock);
261 
262 	if (goto_ch)
263 		tcf_chain_put_by_act(goto_ch);
264 	if (p)
265 		kfree_rcu(p, rcu);
266 
267 	return ret;
268 put_chain:
269 	if (goto_ch)
270 		tcf_chain_put_by_act(goto_ch);
271 release_idr:
272 	tcf_idr_release(*a, bind);
273 	return err;
274 }
275 
276 static void tcf_vlan_cleanup(struct tc_action *a)
277 {
278 	struct tcf_vlan *v = to_vlan(a);
279 	struct tcf_vlan_params *p;
280 
281 	p = rcu_dereference_protected(v->vlan_p, 1);
282 	if (p)
283 		kfree_rcu(p, rcu);
284 }
285 
286 static int tcf_vlan_dump(struct sk_buff *skb, struct tc_action *a,
287 			 int bind, int ref)
288 {
289 	unsigned char *b = skb_tail_pointer(skb);
290 	struct tcf_vlan *v = to_vlan(a);
291 	struct tcf_vlan_params *p;
292 	struct tc_vlan opt = {
293 		.index    = v->tcf_index,
294 		.refcnt   = refcount_read(&v->tcf_refcnt) - ref,
295 		.bindcnt  = atomic_read(&v->tcf_bindcnt) - bind,
296 	};
297 	struct tcf_t t;
298 
299 	spin_lock_bh(&v->tcf_lock);
300 	opt.action = v->tcf_action;
301 	p = rcu_dereference_protected(v->vlan_p, lockdep_is_held(&v->tcf_lock));
302 	opt.v_action = p->tcfv_action;
303 	if (nla_put(skb, TCA_VLAN_PARMS, sizeof(opt), &opt))
304 		goto nla_put_failure;
305 
306 	if ((p->tcfv_action == TCA_VLAN_ACT_PUSH ||
307 	     p->tcfv_action == TCA_VLAN_ACT_MODIFY) &&
308 	    (nla_put_u16(skb, TCA_VLAN_PUSH_VLAN_ID, p->tcfv_push_vid) ||
309 	     nla_put_be16(skb, TCA_VLAN_PUSH_VLAN_PROTOCOL,
310 			  p->tcfv_push_proto) ||
311 	     (p->tcfv_push_prio_exists &&
312 	      nla_put_u8(skb, TCA_VLAN_PUSH_VLAN_PRIORITY, p->tcfv_push_prio))))
313 		goto nla_put_failure;
314 
315 	if (p->tcfv_action == TCA_VLAN_ACT_PUSH_ETH) {
316 		if (nla_put(skb, TCA_VLAN_PUSH_ETH_DST, ETH_ALEN,
317 			    p->tcfv_push_dst))
318 			goto nla_put_failure;
319 		if (nla_put(skb, TCA_VLAN_PUSH_ETH_SRC, ETH_ALEN,
320 			    p->tcfv_push_src))
321 			goto nla_put_failure;
322 	}
323 
324 	tcf_tm_dump(&t, &v->tcf_tm);
325 	if (nla_put_64bit(skb, TCA_VLAN_TM, sizeof(t), &t, TCA_VLAN_PAD))
326 		goto nla_put_failure;
327 	spin_unlock_bh(&v->tcf_lock);
328 
329 	return skb->len;
330 
331 nla_put_failure:
332 	spin_unlock_bh(&v->tcf_lock);
333 	nlmsg_trim(skb, b);
334 	return -1;
335 }
336 
337 static void tcf_vlan_stats_update(struct tc_action *a, u64 bytes, u64 packets,
338 				  u64 drops, u64 lastuse, bool hw)
339 {
340 	struct tcf_vlan *v = to_vlan(a);
341 	struct tcf_t *tm = &v->tcf_tm;
342 
343 	tcf_action_update_stats(a, bytes, packets, drops, hw);
344 	tm->lastuse = max_t(u64, tm->lastuse, lastuse);
345 }
346 
347 static size_t tcf_vlan_get_fill_size(const struct tc_action *act)
348 {
349 	return nla_total_size(sizeof(struct tc_vlan))
350 		+ nla_total_size(sizeof(u16)) /* TCA_VLAN_PUSH_VLAN_ID */
351 		+ nla_total_size(sizeof(u16)) /* TCA_VLAN_PUSH_VLAN_PROTOCOL */
352 		+ nla_total_size(sizeof(u8)); /* TCA_VLAN_PUSH_VLAN_PRIORITY */
353 }
354 
355 static int tcf_vlan_offload_act_setup(struct tc_action *act, void *entry_data,
356 				      u32 *index_inc, bool bind,
357 				      struct netlink_ext_ack *extack)
358 {
359 	if (bind) {
360 		struct flow_action_entry *entry = entry_data;
361 
362 		switch (tcf_vlan_action(act)) {
363 		case TCA_VLAN_ACT_PUSH:
364 			entry->id = FLOW_ACTION_VLAN_PUSH;
365 			entry->vlan.vid = tcf_vlan_push_vid(act);
366 			entry->vlan.proto = tcf_vlan_push_proto(act);
367 			entry->vlan.prio = tcf_vlan_push_prio(act);
368 			break;
369 		case TCA_VLAN_ACT_POP:
370 			entry->id = FLOW_ACTION_VLAN_POP;
371 			break;
372 		case TCA_VLAN_ACT_MODIFY:
373 			entry->id = FLOW_ACTION_VLAN_MANGLE;
374 			entry->vlan.vid = tcf_vlan_push_vid(act);
375 			entry->vlan.proto = tcf_vlan_push_proto(act);
376 			entry->vlan.prio = tcf_vlan_push_prio(act);
377 			break;
378 		case TCA_VLAN_ACT_POP_ETH:
379 			entry->id = FLOW_ACTION_VLAN_POP_ETH;
380 			break;
381 		case TCA_VLAN_ACT_PUSH_ETH:
382 			entry->id = FLOW_ACTION_VLAN_PUSH_ETH;
383 			tcf_vlan_push_eth(entry->vlan_push_eth.src, entry->vlan_push_eth.dst, act);
384 			break;
385 		default:
386 			NL_SET_ERR_MSG_MOD(extack, "Unsupported vlan action mode offload");
387 			return -EOPNOTSUPP;
388 		}
389 		*index_inc = 1;
390 	} else {
391 		struct flow_offload_action *fl_action = entry_data;
392 
393 		switch (tcf_vlan_action(act)) {
394 		case TCA_VLAN_ACT_PUSH:
395 			fl_action->id = FLOW_ACTION_VLAN_PUSH;
396 			break;
397 		case TCA_VLAN_ACT_POP:
398 			fl_action->id = FLOW_ACTION_VLAN_POP;
399 			break;
400 		case TCA_VLAN_ACT_MODIFY:
401 			fl_action->id = FLOW_ACTION_VLAN_MANGLE;
402 			break;
403 		case TCA_VLAN_ACT_POP_ETH:
404 			fl_action->id = FLOW_ACTION_VLAN_POP_ETH;
405 			break;
406 		case TCA_VLAN_ACT_PUSH_ETH:
407 			fl_action->id = FLOW_ACTION_VLAN_PUSH_ETH;
408 			break;
409 		default:
410 			return -EOPNOTSUPP;
411 		}
412 	}
413 
414 	return 0;
415 }
416 
417 static struct tc_action_ops act_vlan_ops = {
418 	.kind		=	"vlan",
419 	.id		=	TCA_ID_VLAN,
420 	.owner		=	THIS_MODULE,
421 	.act		=	tcf_vlan_act,
422 	.dump		=	tcf_vlan_dump,
423 	.init		=	tcf_vlan_init,
424 	.cleanup	=	tcf_vlan_cleanup,
425 	.stats_update	=	tcf_vlan_stats_update,
426 	.get_fill_size	=	tcf_vlan_get_fill_size,
427 	.offload_act_setup =	tcf_vlan_offload_act_setup,
428 	.size		=	sizeof(struct tcf_vlan),
429 };
430 MODULE_ALIAS_NET_ACT("vlan");
431 
432 static __net_init int vlan_init_net(struct net *net)
433 {
434 	struct tc_action_net *tn = net_generic(net, act_vlan_ops.net_id);
435 
436 	return tc_action_net_init(net, tn, &act_vlan_ops);
437 }
438 
439 static void __net_exit vlan_exit_net(struct list_head *net_list)
440 {
441 	tc_action_net_exit(net_list, act_vlan_ops.net_id);
442 }
443 
444 static struct pernet_operations vlan_net_ops = {
445 	.init = vlan_init_net,
446 	.exit_batch = vlan_exit_net,
447 	.id   = &act_vlan_ops.net_id,
448 	.size = sizeof(struct tc_action_net),
449 };
450 
451 static int __init vlan_init_module(void)
452 {
453 	return tcf_register_action(&act_vlan_ops, &vlan_net_ops);
454 }
455 
456 static void __exit vlan_cleanup_module(void)
457 {
458 	tcf_unregister_action(&act_vlan_ops, &vlan_net_ops);
459 }
460 
461 module_init(vlan_init_module);
462 module_exit(vlan_cleanup_module);
463 
464 MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>");
465 MODULE_DESCRIPTION("vlan manipulation actions");
466 MODULE_LICENSE("GPL v2");
467