xref: /linux/net/sched/act_vlan.c (revision 90e0d94d369d342e735a75174439482119b6c393)
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 
16 #include <linux/tc_act/tc_vlan.h>
17 #include <net/tc_act/tc_vlan.h>
18 
19 static struct tc_action_ops act_vlan_ops;
20 
21 static int tcf_vlan_act(struct sk_buff *skb, const struct tc_action *a,
22 			struct tcf_result *res)
23 {
24 	struct tcf_vlan *v = to_vlan(a);
25 	struct tcf_vlan_params *p;
26 	int action;
27 	int err;
28 	u16 tci;
29 
30 	tcf_lastuse_update(&v->tcf_tm);
31 	tcf_action_update_bstats(&v->common, skb);
32 
33 	/* Ensure 'data' points at mac_header prior calling vlan manipulating
34 	 * functions.
35 	 */
36 	if (skb_at_tc_ingress(skb))
37 		skb_push_rcsum(skb, skb->mac_len);
38 
39 	action = READ_ONCE(v->tcf_action);
40 
41 	p = rcu_dereference_bh(v->vlan_p);
42 
43 	switch (p->tcfv_action) {
44 	case TCA_VLAN_ACT_POP:
45 		err = skb_vlan_pop(skb);
46 		if (err)
47 			goto drop;
48 		break;
49 	case TCA_VLAN_ACT_PUSH:
50 		err = skb_vlan_push(skb, p->tcfv_push_proto, p->tcfv_push_vid |
51 				    (p->tcfv_push_prio << VLAN_PRIO_SHIFT));
52 		if (err)
53 			goto drop;
54 		break;
55 	case TCA_VLAN_ACT_MODIFY:
56 		/* No-op if no vlan tag (either hw-accel or in-payload) */
57 		if (!skb_vlan_tagged(skb))
58 			goto out;
59 		/* extract existing tag (and guarantee no hw-accel tag) */
60 		if (skb_vlan_tag_present(skb)) {
61 			tci = skb_vlan_tag_get(skb);
62 			__vlan_hwaccel_clear_tag(skb);
63 		} else {
64 			/* in-payload vlan tag, pop it */
65 			err = __skb_vlan_pop(skb, &tci);
66 			if (err)
67 				goto drop;
68 		}
69 		/* replace the vid */
70 		tci = (tci & ~VLAN_VID_MASK) | p->tcfv_push_vid;
71 		/* replace prio bits, if tcfv_push_prio specified */
72 		if (p->tcfv_push_prio_exists) {
73 			tci &= ~VLAN_PRIO_MASK;
74 			tci |= p->tcfv_push_prio << VLAN_PRIO_SHIFT;
75 		}
76 		/* put updated tci as hwaccel tag */
77 		__vlan_hwaccel_put_tag(skb, p->tcfv_push_proto, tci);
78 		break;
79 	case TCA_VLAN_ACT_POP_ETH:
80 		err = skb_eth_pop(skb);
81 		if (err)
82 			goto drop;
83 		break;
84 	case TCA_VLAN_ACT_PUSH_ETH:
85 		err = skb_eth_push(skb, p->tcfv_push_dst, p->tcfv_push_src);
86 		if (err)
87 			goto drop;
88 		break;
89 	default:
90 		BUG();
91 	}
92 
93 out:
94 	if (skb_at_tc_ingress(skb))
95 		skb_pull_rcsum(skb, skb->mac_len);
96 
97 	return 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 0;
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 	spin_lock_bh(&v->tcf_lock);
256 	goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
257 	p = rcu_replace_pointer(v->vlan_p, p, lockdep_is_held(&v->tcf_lock));
258 	spin_unlock_bh(&v->tcf_lock);
259 
260 	if (goto_ch)
261 		tcf_chain_put_by_act(goto_ch);
262 	if (p)
263 		kfree_rcu(p, rcu);
264 
265 	return ret;
266 put_chain:
267 	if (goto_ch)
268 		tcf_chain_put_by_act(goto_ch);
269 release_idr:
270 	tcf_idr_release(*a, bind);
271 	return err;
272 }
273 
274 static void tcf_vlan_cleanup(struct tc_action *a)
275 {
276 	struct tcf_vlan *v = to_vlan(a);
277 	struct tcf_vlan_params *p;
278 
279 	p = rcu_dereference_protected(v->vlan_p, 1);
280 	if (p)
281 		kfree_rcu(p, rcu);
282 }
283 
284 static int tcf_vlan_dump(struct sk_buff *skb, struct tc_action *a,
285 			 int bind, int ref)
286 {
287 	unsigned char *b = skb_tail_pointer(skb);
288 	struct tcf_vlan *v = to_vlan(a);
289 	struct tcf_vlan_params *p;
290 	struct tc_vlan opt = {
291 		.index    = v->tcf_index,
292 		.refcnt   = refcount_read(&v->tcf_refcnt) - ref,
293 		.bindcnt  = atomic_read(&v->tcf_bindcnt) - bind,
294 	};
295 	struct tcf_t t;
296 
297 	spin_lock_bh(&v->tcf_lock);
298 	opt.action = v->tcf_action;
299 	p = rcu_dereference_protected(v->vlan_p, lockdep_is_held(&v->tcf_lock));
300 	opt.v_action = p->tcfv_action;
301 	if (nla_put(skb, TCA_VLAN_PARMS, sizeof(opt), &opt))
302 		goto nla_put_failure;
303 
304 	if ((p->tcfv_action == TCA_VLAN_ACT_PUSH ||
305 	     p->tcfv_action == TCA_VLAN_ACT_MODIFY) &&
306 	    (nla_put_u16(skb, TCA_VLAN_PUSH_VLAN_ID, p->tcfv_push_vid) ||
307 	     nla_put_be16(skb, TCA_VLAN_PUSH_VLAN_PROTOCOL,
308 			  p->tcfv_push_proto) ||
309 	     (p->tcfv_push_prio_exists &&
310 	      nla_put_u8(skb, TCA_VLAN_PUSH_VLAN_PRIORITY, p->tcfv_push_prio))))
311 		goto nla_put_failure;
312 
313 	if (p->tcfv_action == TCA_VLAN_ACT_PUSH_ETH) {
314 		if (nla_put(skb, TCA_VLAN_PUSH_ETH_DST, ETH_ALEN,
315 			    p->tcfv_push_dst))
316 			goto nla_put_failure;
317 		if (nla_put(skb, TCA_VLAN_PUSH_ETH_SRC, ETH_ALEN,
318 			    p->tcfv_push_src))
319 			goto nla_put_failure;
320 	}
321 
322 	tcf_tm_dump(&t, &v->tcf_tm);
323 	if (nla_put_64bit(skb, TCA_VLAN_TM, sizeof(t), &t, TCA_VLAN_PAD))
324 		goto nla_put_failure;
325 	spin_unlock_bh(&v->tcf_lock);
326 
327 	return skb->len;
328 
329 nla_put_failure:
330 	spin_unlock_bh(&v->tcf_lock);
331 	nlmsg_trim(skb, b);
332 	return -1;
333 }
334 
335 static void tcf_vlan_stats_update(struct tc_action *a, u64 bytes, u64 packets,
336 				  u64 drops, u64 lastuse, bool hw)
337 {
338 	struct tcf_vlan *v = to_vlan(a);
339 	struct tcf_t *tm = &v->tcf_tm;
340 
341 	tcf_action_update_stats(a, bytes, packets, drops, hw);
342 	tm->lastuse = max_t(u64, tm->lastuse, lastuse);
343 }
344 
345 static size_t tcf_vlan_get_fill_size(const struct tc_action *act)
346 {
347 	return nla_total_size(sizeof(struct tc_vlan))
348 		+ nla_total_size(sizeof(u16)) /* TCA_VLAN_PUSH_VLAN_ID */
349 		+ nla_total_size(sizeof(u16)) /* TCA_VLAN_PUSH_VLAN_PROTOCOL */
350 		+ nla_total_size(sizeof(u8)); /* TCA_VLAN_PUSH_VLAN_PRIORITY */
351 }
352 
353 static int tcf_vlan_offload_act_setup(struct tc_action *act, void *entry_data,
354 				      u32 *index_inc, bool bind,
355 				      struct netlink_ext_ack *extack)
356 {
357 	if (bind) {
358 		struct flow_action_entry *entry = entry_data;
359 
360 		switch (tcf_vlan_action(act)) {
361 		case TCA_VLAN_ACT_PUSH:
362 			entry->id = FLOW_ACTION_VLAN_PUSH;
363 			entry->vlan.vid = tcf_vlan_push_vid(act);
364 			entry->vlan.proto = tcf_vlan_push_proto(act);
365 			entry->vlan.prio = tcf_vlan_push_prio(act);
366 			break;
367 		case TCA_VLAN_ACT_POP:
368 			entry->id = FLOW_ACTION_VLAN_POP;
369 			break;
370 		case TCA_VLAN_ACT_MODIFY:
371 			entry->id = FLOW_ACTION_VLAN_MANGLE;
372 			entry->vlan.vid = tcf_vlan_push_vid(act);
373 			entry->vlan.proto = tcf_vlan_push_proto(act);
374 			entry->vlan.prio = tcf_vlan_push_prio(act);
375 			break;
376 		case TCA_VLAN_ACT_POP_ETH:
377 			entry->id = FLOW_ACTION_VLAN_POP_ETH;
378 			break;
379 		case TCA_VLAN_ACT_PUSH_ETH:
380 			entry->id = FLOW_ACTION_VLAN_PUSH_ETH;
381 			tcf_vlan_push_eth(entry->vlan_push_eth.src, entry->vlan_push_eth.dst, act);
382 			break;
383 		default:
384 			NL_SET_ERR_MSG_MOD(extack, "Unsupported vlan action mode offload");
385 			return -EOPNOTSUPP;
386 		}
387 		*index_inc = 1;
388 	} else {
389 		struct flow_offload_action *fl_action = entry_data;
390 
391 		switch (tcf_vlan_action(act)) {
392 		case TCA_VLAN_ACT_PUSH:
393 			fl_action->id = FLOW_ACTION_VLAN_PUSH;
394 			break;
395 		case TCA_VLAN_ACT_POP:
396 			fl_action->id = FLOW_ACTION_VLAN_POP;
397 			break;
398 		case TCA_VLAN_ACT_MODIFY:
399 			fl_action->id = FLOW_ACTION_VLAN_MANGLE;
400 			break;
401 		case TCA_VLAN_ACT_POP_ETH:
402 			fl_action->id = FLOW_ACTION_VLAN_POP_ETH;
403 			break;
404 		case TCA_VLAN_ACT_PUSH_ETH:
405 			fl_action->id = FLOW_ACTION_VLAN_PUSH_ETH;
406 			break;
407 		default:
408 			return -EOPNOTSUPP;
409 		}
410 	}
411 
412 	return 0;
413 }
414 
415 static struct tc_action_ops act_vlan_ops = {
416 	.kind		=	"vlan",
417 	.id		=	TCA_ID_VLAN,
418 	.owner		=	THIS_MODULE,
419 	.act		=	tcf_vlan_act,
420 	.dump		=	tcf_vlan_dump,
421 	.init		=	tcf_vlan_init,
422 	.cleanup	=	tcf_vlan_cleanup,
423 	.stats_update	=	tcf_vlan_stats_update,
424 	.get_fill_size	=	tcf_vlan_get_fill_size,
425 	.offload_act_setup =	tcf_vlan_offload_act_setup,
426 	.size		=	sizeof(struct tcf_vlan),
427 };
428 
429 static __net_init int vlan_init_net(struct net *net)
430 {
431 	struct tc_action_net *tn = net_generic(net, act_vlan_ops.net_id);
432 
433 	return tc_action_net_init(net, tn, &act_vlan_ops);
434 }
435 
436 static void __net_exit vlan_exit_net(struct list_head *net_list)
437 {
438 	tc_action_net_exit(net_list, act_vlan_ops.net_id);
439 }
440 
441 static struct pernet_operations vlan_net_ops = {
442 	.init = vlan_init_net,
443 	.exit_batch = vlan_exit_net,
444 	.id   = &act_vlan_ops.net_id,
445 	.size = sizeof(struct tc_action_net),
446 };
447 
448 static int __init vlan_init_module(void)
449 {
450 	return tcf_register_action(&act_vlan_ops, &vlan_net_ops);
451 }
452 
453 static void __exit vlan_cleanup_module(void)
454 {
455 	tcf_unregister_action(&act_vlan_ops, &vlan_net_ops);
456 }
457 
458 module_init(vlan_init_module);
459 module_exit(vlan_cleanup_module);
460 
461 MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>");
462 MODULE_DESCRIPTION("vlan manipulation actions");
463 MODULE_LICENSE("GPL v2");
464