xref: /linux/net/sched/act_vlan.c (revision ca853314e78b0a65c20b6a889a23c31f918d4aa2)
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) {
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 	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 		if (tb[TCA_VLAN_PUSH_VLAN_PRIORITY])
193 			push_prio = nla_get_u8(tb[TCA_VLAN_PUSH_VLAN_PRIORITY]);
194 		break;
195 	case TCA_VLAN_ACT_POP_ETH:
196 		break;
197 	case TCA_VLAN_ACT_PUSH_ETH:
198 		if (!tb[TCA_VLAN_PUSH_ETH_DST] || !tb[TCA_VLAN_PUSH_ETH_SRC]) {
199 			if (exists)
200 				tcf_idr_release(*a, bind);
201 			else
202 				tcf_idr_cleanup(tn, index);
203 			return -EINVAL;
204 		}
205 		break;
206 	default:
207 		if (exists)
208 			tcf_idr_release(*a, bind);
209 		else
210 			tcf_idr_cleanup(tn, index);
211 		return -EINVAL;
212 	}
213 	action = parm->v_action;
214 
215 	if (!exists) {
216 		ret = tcf_idr_create_from_flags(tn, index, est, a,
217 						&act_vlan_ops, bind, flags);
218 		if (ret) {
219 			tcf_idr_cleanup(tn, index);
220 			return ret;
221 		}
222 
223 		ret = ACT_P_CREATED;
224 	} else if (!ovr) {
225 		tcf_idr_release(*a, bind);
226 		return -EEXIST;
227 	}
228 
229 	err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
230 	if (err < 0)
231 		goto release_idr;
232 
233 	v = to_vlan(*a);
234 
235 	p = kzalloc(sizeof(*p), GFP_KERNEL);
236 	if (!p) {
237 		err = -ENOMEM;
238 		goto put_chain;
239 	}
240 
241 	p->tcfv_action = action;
242 	p->tcfv_push_vid = push_vid;
243 	p->tcfv_push_prio = push_prio;
244 	p->tcfv_push_proto = push_proto;
245 
246 	if (action == TCA_VLAN_ACT_PUSH_ETH) {
247 		nla_memcpy(&p->tcfv_push_dst, tb[TCA_VLAN_PUSH_ETH_DST],
248 			   ETH_ALEN);
249 		nla_memcpy(&p->tcfv_push_src, tb[TCA_VLAN_PUSH_ETH_SRC],
250 			   ETH_ALEN);
251 	}
252 
253 	spin_lock_bh(&v->tcf_lock);
254 	goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
255 	p = rcu_replace_pointer(v->vlan_p, p, lockdep_is_held(&v->tcf_lock));
256 	spin_unlock_bh(&v->tcf_lock);
257 
258 	if (goto_ch)
259 		tcf_chain_put_by_act(goto_ch);
260 	if (p)
261 		kfree_rcu(p, rcu);
262 
263 	return ret;
264 put_chain:
265 	if (goto_ch)
266 		tcf_chain_put_by_act(goto_ch);
267 release_idr:
268 	tcf_idr_release(*a, bind);
269 	return err;
270 }
271 
272 static void tcf_vlan_cleanup(struct tc_action *a)
273 {
274 	struct tcf_vlan *v = to_vlan(a);
275 	struct tcf_vlan_params *p;
276 
277 	p = rcu_dereference_protected(v->vlan_p, 1);
278 	if (p)
279 		kfree_rcu(p, rcu);
280 }
281 
282 static int tcf_vlan_dump(struct sk_buff *skb, struct tc_action *a,
283 			 int bind, int ref)
284 {
285 	unsigned char *b = skb_tail_pointer(skb);
286 	struct tcf_vlan *v = to_vlan(a);
287 	struct tcf_vlan_params *p;
288 	struct tc_vlan opt = {
289 		.index    = v->tcf_index,
290 		.refcnt   = refcount_read(&v->tcf_refcnt) - ref,
291 		.bindcnt  = atomic_read(&v->tcf_bindcnt) - bind,
292 	};
293 	struct tcf_t t;
294 
295 	spin_lock_bh(&v->tcf_lock);
296 	opt.action = v->tcf_action;
297 	p = rcu_dereference_protected(v->vlan_p, lockdep_is_held(&v->tcf_lock));
298 	opt.v_action = p->tcfv_action;
299 	if (nla_put(skb, TCA_VLAN_PARMS, sizeof(opt), &opt))
300 		goto nla_put_failure;
301 
302 	if ((p->tcfv_action == TCA_VLAN_ACT_PUSH ||
303 	     p->tcfv_action == TCA_VLAN_ACT_MODIFY) &&
304 	    (nla_put_u16(skb, TCA_VLAN_PUSH_VLAN_ID, p->tcfv_push_vid) ||
305 	     nla_put_be16(skb, TCA_VLAN_PUSH_VLAN_PROTOCOL,
306 			  p->tcfv_push_proto) ||
307 	     (nla_put_u8(skb, TCA_VLAN_PUSH_VLAN_PRIORITY,
308 					      p->tcfv_push_prio))))
309 		goto nla_put_failure;
310 
311 	if (p->tcfv_action == TCA_VLAN_ACT_PUSH_ETH) {
312 		if (nla_put(skb, TCA_VLAN_PUSH_ETH_DST, ETH_ALEN,
313 			    p->tcfv_push_dst))
314 			goto nla_put_failure;
315 		if (nla_put(skb, TCA_VLAN_PUSH_ETH_SRC, ETH_ALEN,
316 			    p->tcfv_push_src))
317 			goto nla_put_failure;
318 	}
319 
320 	tcf_tm_dump(&t, &v->tcf_tm);
321 	if (nla_put_64bit(skb, TCA_VLAN_TM, sizeof(t), &t, TCA_VLAN_PAD))
322 		goto nla_put_failure;
323 	spin_unlock_bh(&v->tcf_lock);
324 
325 	return skb->len;
326 
327 nla_put_failure:
328 	spin_unlock_bh(&v->tcf_lock);
329 	nlmsg_trim(skb, b);
330 	return -1;
331 }
332 
333 static int tcf_vlan_walker(struct net *net, struct sk_buff *skb,
334 			   struct netlink_callback *cb, int type,
335 			   const struct tc_action_ops *ops,
336 			   struct netlink_ext_ack *extack)
337 {
338 	struct tc_action_net *tn = net_generic(net, vlan_net_id);
339 
340 	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
341 }
342 
343 static void tcf_vlan_stats_update(struct tc_action *a, u64 bytes, u64 packets,
344 				  u64 drops, u64 lastuse, bool hw)
345 {
346 	struct tcf_vlan *v = to_vlan(a);
347 	struct tcf_t *tm = &v->tcf_tm;
348 
349 	tcf_action_update_stats(a, bytes, packets, drops, hw);
350 	tm->lastuse = max_t(u64, tm->lastuse, lastuse);
351 }
352 
353 static int tcf_vlan_search(struct net *net, struct tc_action **a, u32 index)
354 {
355 	struct tc_action_net *tn = net_generic(net, vlan_net_id);
356 
357 	return tcf_idr_search(tn, a, index);
358 }
359 
360 static size_t tcf_vlan_get_fill_size(const struct tc_action *act)
361 {
362 	return nla_total_size(sizeof(struct tc_vlan))
363 		+ nla_total_size(sizeof(u16)) /* TCA_VLAN_PUSH_VLAN_ID */
364 		+ nla_total_size(sizeof(u16)) /* TCA_VLAN_PUSH_VLAN_PROTOCOL */
365 		+ nla_total_size(sizeof(u8)); /* TCA_VLAN_PUSH_VLAN_PRIORITY */
366 }
367 
368 static struct tc_action_ops act_vlan_ops = {
369 	.kind		=	"vlan",
370 	.id		=	TCA_ID_VLAN,
371 	.owner		=	THIS_MODULE,
372 	.act		=	tcf_vlan_act,
373 	.dump		=	tcf_vlan_dump,
374 	.init		=	tcf_vlan_init,
375 	.cleanup	=	tcf_vlan_cleanup,
376 	.walk		=	tcf_vlan_walker,
377 	.stats_update	=	tcf_vlan_stats_update,
378 	.get_fill_size	=	tcf_vlan_get_fill_size,
379 	.lookup		=	tcf_vlan_search,
380 	.size		=	sizeof(struct tcf_vlan),
381 };
382 
383 static __net_init int vlan_init_net(struct net *net)
384 {
385 	struct tc_action_net *tn = net_generic(net, vlan_net_id);
386 
387 	return tc_action_net_init(net, tn, &act_vlan_ops);
388 }
389 
390 static void __net_exit vlan_exit_net(struct list_head *net_list)
391 {
392 	tc_action_net_exit(net_list, vlan_net_id);
393 }
394 
395 static struct pernet_operations vlan_net_ops = {
396 	.init = vlan_init_net,
397 	.exit_batch = vlan_exit_net,
398 	.id   = &vlan_net_id,
399 	.size = sizeof(struct tc_action_net),
400 };
401 
402 static int __init vlan_init_module(void)
403 {
404 	return tcf_register_action(&act_vlan_ops, &vlan_net_ops);
405 }
406 
407 static void __exit vlan_cleanup_module(void)
408 {
409 	tcf_unregister_action(&act_vlan_ops, &vlan_net_ops);
410 }
411 
412 module_init(vlan_init_module);
413 module_exit(vlan_cleanup_module);
414 
415 MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>");
416 MODULE_DESCRIPTION("vlan manipulation actions");
417 MODULE_LICENSE("GPL v2");
418