xref: /linux/net/sched/act_vlan.c (revision bb5b94f5bbe75470912b70fb08880fc5273aa62d)
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 unsigned int vlan_net_id;
20 static struct tc_action_ops act_vlan_ops;
21 
22 static int tcf_vlan_act(struct sk_buff *skb, const struct tc_action *a,
23 			struct tcf_result *res)
24 {
25 	struct tcf_vlan *v = to_vlan(a);
26 	struct tcf_vlan_params *p;
27 	int action;
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 	action = READ_ONCE(v->tcf_action);
41 
42 	p = rcu_dereference_bh(v->vlan_p);
43 
44 	switch (p->tcfv_action) {
45 	case TCA_VLAN_ACT_POP:
46 		err = skb_vlan_pop(skb);
47 		if (err)
48 			goto drop;
49 		break;
50 	case TCA_VLAN_ACT_PUSH:
51 		err = skb_vlan_push(skb, p->tcfv_push_proto, p->tcfv_push_vid |
52 				    (p->tcfv_push_prio << VLAN_PRIO_SHIFT));
53 		if (err)
54 			goto drop;
55 		break;
56 	case TCA_VLAN_ACT_MODIFY:
57 		/* No-op if no vlan tag (either hw-accel or in-payload) */
58 		if (!skb_vlan_tagged(skb))
59 			goto out;
60 		/* extract existing tag (and guarantee no hw-accel tag) */
61 		if (skb_vlan_tag_present(skb)) {
62 			tci = skb_vlan_tag_get(skb);
63 			__vlan_hwaccel_clear_tag(skb);
64 		} else {
65 			/* in-payload vlan tag, pop it */
66 			err = __skb_vlan_pop(skb, &tci);
67 			if (err)
68 				goto drop;
69 		}
70 		/* replace the vid */
71 		tci = (tci & ~VLAN_VID_MASK) | p->tcfv_push_vid;
72 		/* replace prio bits, if tcfv_push_prio specified */
73 		if (p->tcfv_push_prio_exists) {
74 			tci &= ~VLAN_PRIO_MASK;
75 			tci |= p->tcfv_push_prio << VLAN_PRIO_SHIFT;
76 		}
77 		/* put updated tci as hwaccel tag */
78 		__vlan_hwaccel_put_tag(skb, p->tcfv_push_proto, tci);
79 		break;
80 	case TCA_VLAN_ACT_POP_ETH:
81 		err = skb_eth_pop(skb);
82 		if (err)
83 			goto drop;
84 		break;
85 	case TCA_VLAN_ACT_PUSH_ETH:
86 		err = skb_eth_push(skb, p->tcfv_push_dst, p->tcfv_push_src);
87 		if (err)
88 			goto drop;
89 		break;
90 	default:
91 		BUG();
92 	}
93 
94 out:
95 	if (skb_at_tc_ingress(skb))
96 		skb_pull_rcsum(skb, skb->mac_len);
97 
98 	return action;
99 
100 drop:
101 	tcf_action_inc_drop_qstats(&v->common);
102 	return TC_ACT_SHOT;
103 }
104 
105 static const struct nla_policy vlan_policy[TCA_VLAN_MAX + 1] = {
106 	[TCA_VLAN_UNSPEC]		= { .strict_start_type = TCA_VLAN_PUSH_ETH_DST },
107 	[TCA_VLAN_PARMS]		= { .len = sizeof(struct tc_vlan) },
108 	[TCA_VLAN_PUSH_VLAN_ID]		= { .type = NLA_U16 },
109 	[TCA_VLAN_PUSH_VLAN_PROTOCOL]	= { .type = NLA_U16 },
110 	[TCA_VLAN_PUSH_VLAN_PRIORITY]	= { .type = NLA_U8 },
111 	[TCA_VLAN_PUSH_ETH_DST]		= NLA_POLICY_ETH_ADDR,
112 	[TCA_VLAN_PUSH_ETH_SRC]		= NLA_POLICY_ETH_ADDR,
113 };
114 
115 static int tcf_vlan_init(struct net *net, struct nlattr *nla,
116 			 struct nlattr *est, struct tc_action **a,
117 			 int ovr, int bind, bool rtnl_held,
118 			 struct tcf_proto *tp, u32 flags,
119 			 struct netlink_ext_ack *extack)
120 {
121 	struct tc_action_net *tn = net_generic(net, vlan_net_id);
122 	struct nlattr *tb[TCA_VLAN_MAX + 1];
123 	struct tcf_chain *goto_ch = NULL;
124 	bool push_prio_exists = false;
125 	struct tcf_vlan_params *p;
126 	struct tc_vlan *parm;
127 	struct tcf_vlan *v;
128 	int action;
129 	u16 push_vid = 0;
130 	__be16 push_proto = 0;
131 	u8 push_prio = 0;
132 	bool exists = false;
133 	int ret = 0, err;
134 	u32 index;
135 
136 	if (!nla)
137 		return -EINVAL;
138 
139 	err = nla_parse_nested_deprecated(tb, TCA_VLAN_MAX, nla, vlan_policy,
140 					  NULL);
141 	if (err < 0)
142 		return err;
143 
144 	if (!tb[TCA_VLAN_PARMS])
145 		return -EINVAL;
146 	parm = nla_data(tb[TCA_VLAN_PARMS]);
147 	index = parm->index;
148 	err = tcf_idr_check_alloc(tn, &index, a, bind);
149 	if (err < 0)
150 		return err;
151 	exists = err;
152 	if (exists && bind)
153 		return 0;
154 
155 	switch (parm->v_action) {
156 	case TCA_VLAN_ACT_POP:
157 		break;
158 	case TCA_VLAN_ACT_PUSH:
159 	case TCA_VLAN_ACT_MODIFY:
160 		if (!tb[TCA_VLAN_PUSH_VLAN_ID]) {
161 			if (exists)
162 				tcf_idr_release(*a, bind);
163 			else
164 				tcf_idr_cleanup(tn, index);
165 			return -EINVAL;
166 		}
167 		push_vid = nla_get_u16(tb[TCA_VLAN_PUSH_VLAN_ID]);
168 		if (push_vid >= VLAN_VID_MASK) {
169 			if (exists)
170 				tcf_idr_release(*a, bind);
171 			else
172 				tcf_idr_cleanup(tn, index);
173 			return -ERANGE;
174 		}
175 
176 		if (tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]) {
177 			push_proto = nla_get_be16(tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]);
178 			switch (push_proto) {
179 			case htons(ETH_P_8021Q):
180 			case htons(ETH_P_8021AD):
181 				break;
182 			default:
183 				if (exists)
184 					tcf_idr_release(*a, bind);
185 				else
186 					tcf_idr_cleanup(tn, index);
187 				return -EPROTONOSUPPORT;
188 			}
189 		} else {
190 			push_proto = htons(ETH_P_8021Q);
191 		}
192 
193 		push_prio_exists = !!tb[TCA_VLAN_PUSH_VLAN_PRIORITY];
194 		if (push_prio_exists)
195 			push_prio = nla_get_u8(tb[TCA_VLAN_PUSH_VLAN_PRIORITY]);
196 		break;
197 	case TCA_VLAN_ACT_POP_ETH:
198 		break;
199 	case TCA_VLAN_ACT_PUSH_ETH:
200 		if (!tb[TCA_VLAN_PUSH_ETH_DST] || !tb[TCA_VLAN_PUSH_ETH_SRC]) {
201 			if (exists)
202 				tcf_idr_release(*a, bind);
203 			else
204 				tcf_idr_cleanup(tn, index);
205 			return -EINVAL;
206 		}
207 		break;
208 	default:
209 		if (exists)
210 			tcf_idr_release(*a, bind);
211 		else
212 			tcf_idr_cleanup(tn, index);
213 		return -EINVAL;
214 	}
215 	action = parm->v_action;
216 
217 	if (!exists) {
218 		ret = tcf_idr_create_from_flags(tn, index, est, a,
219 						&act_vlan_ops, bind, flags);
220 		if (ret) {
221 			tcf_idr_cleanup(tn, index);
222 			return ret;
223 		}
224 
225 		ret = ACT_P_CREATED;
226 	} else if (!ovr) {
227 		tcf_idr_release(*a, bind);
228 		return -EEXIST;
229 	}
230 
231 	err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
232 	if (err < 0)
233 		goto release_idr;
234 
235 	v = to_vlan(*a);
236 
237 	p = kzalloc(sizeof(*p), GFP_KERNEL);
238 	if (!p) {
239 		err = -ENOMEM;
240 		goto put_chain;
241 	}
242 
243 	p->tcfv_action = action;
244 	p->tcfv_push_vid = push_vid;
245 	p->tcfv_push_prio = push_prio;
246 	p->tcfv_push_prio_exists = push_prio_exists || action == TCA_VLAN_ACT_PUSH;
247 	p->tcfv_push_proto = push_proto;
248 
249 	if (action == TCA_VLAN_ACT_PUSH_ETH) {
250 		nla_memcpy(&p->tcfv_push_dst, tb[TCA_VLAN_PUSH_ETH_DST],
251 			   ETH_ALEN);
252 		nla_memcpy(&p->tcfv_push_src, tb[TCA_VLAN_PUSH_ETH_SRC],
253 			   ETH_ALEN);
254 	}
255 
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 	spin_lock_bh(&v->tcf_lock);
299 	opt.action = v->tcf_action;
300 	p = rcu_dereference_protected(v->vlan_p, lockdep_is_held(&v->tcf_lock));
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 	spin_unlock_bh(&v->tcf_lock);
327 
328 	return skb->len;
329 
330 nla_put_failure:
331 	spin_unlock_bh(&v->tcf_lock);
332 	nlmsg_trim(skb, b);
333 	return -1;
334 }
335 
336 static int tcf_vlan_walker(struct net *net, struct sk_buff *skb,
337 			   struct netlink_callback *cb, int type,
338 			   const struct tc_action_ops *ops,
339 			   struct netlink_ext_ack *extack)
340 {
341 	struct tc_action_net *tn = net_generic(net, vlan_net_id);
342 
343 	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
344 }
345 
346 static void tcf_vlan_stats_update(struct tc_action *a, u64 bytes, u64 packets,
347 				  u64 drops, u64 lastuse, bool hw)
348 {
349 	struct tcf_vlan *v = to_vlan(a);
350 	struct tcf_t *tm = &v->tcf_tm;
351 
352 	tcf_action_update_stats(a, bytes, packets, drops, hw);
353 	tm->lastuse = max_t(u64, tm->lastuse, lastuse);
354 }
355 
356 static int tcf_vlan_search(struct net *net, struct tc_action **a, u32 index)
357 {
358 	struct tc_action_net *tn = net_generic(net, vlan_net_id);
359 
360 	return tcf_idr_search(tn, a, index);
361 }
362 
363 static size_t tcf_vlan_get_fill_size(const struct tc_action *act)
364 {
365 	return nla_total_size(sizeof(struct tc_vlan))
366 		+ nla_total_size(sizeof(u16)) /* TCA_VLAN_PUSH_VLAN_ID */
367 		+ nla_total_size(sizeof(u16)) /* TCA_VLAN_PUSH_VLAN_PROTOCOL */
368 		+ nla_total_size(sizeof(u8)); /* TCA_VLAN_PUSH_VLAN_PRIORITY */
369 }
370 
371 static struct tc_action_ops act_vlan_ops = {
372 	.kind		=	"vlan",
373 	.id		=	TCA_ID_VLAN,
374 	.owner		=	THIS_MODULE,
375 	.act		=	tcf_vlan_act,
376 	.dump		=	tcf_vlan_dump,
377 	.init		=	tcf_vlan_init,
378 	.cleanup	=	tcf_vlan_cleanup,
379 	.walk		=	tcf_vlan_walker,
380 	.stats_update	=	tcf_vlan_stats_update,
381 	.get_fill_size	=	tcf_vlan_get_fill_size,
382 	.lookup		=	tcf_vlan_search,
383 	.size		=	sizeof(struct tcf_vlan),
384 };
385 
386 static __net_init int vlan_init_net(struct net *net)
387 {
388 	struct tc_action_net *tn = net_generic(net, vlan_net_id);
389 
390 	return tc_action_net_init(net, tn, &act_vlan_ops);
391 }
392 
393 static void __net_exit vlan_exit_net(struct list_head *net_list)
394 {
395 	tc_action_net_exit(net_list, vlan_net_id);
396 }
397 
398 static struct pernet_operations vlan_net_ops = {
399 	.init = vlan_init_net,
400 	.exit_batch = vlan_exit_net,
401 	.id   = &vlan_net_id,
402 	.size = sizeof(struct tc_action_net),
403 };
404 
405 static int __init vlan_init_module(void)
406 {
407 	return tcf_register_action(&act_vlan_ops, &vlan_net_ops);
408 }
409 
410 static void __exit vlan_cleanup_module(void)
411 {
412 	tcf_unregister_action(&act_vlan_ops, &vlan_net_ops);
413 }
414 
415 module_init(vlan_init_module);
416 module_exit(vlan_cleanup_module);
417 
418 MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>");
419 MODULE_DESCRIPTION("vlan manipulation actions");
420 MODULE_LICENSE("GPL v2");
421