xref: /openbmc/linux/net/sched/act_vlan.c (revision a44e4f3a)
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 	bstats_cpu_update(this_cpu_ptr(v->common.cpu_bstats), 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 	default:
81 		BUG();
82 	}
83 
84 out:
85 	if (skb_at_tc_ingress(skb))
86 		skb_pull_rcsum(skb, skb->mac_len);
87 
88 	return action;
89 
90 drop:
91 	qstats_drop_inc(this_cpu_ptr(v->common.cpu_qstats));
92 	return TC_ACT_SHOT;
93 }
94 
95 static const struct nla_policy vlan_policy[TCA_VLAN_MAX + 1] = {
96 	[TCA_VLAN_PARMS]		= { .len = sizeof(struct tc_vlan) },
97 	[TCA_VLAN_PUSH_VLAN_ID]		= { .type = NLA_U16 },
98 	[TCA_VLAN_PUSH_VLAN_PROTOCOL]	= { .type = NLA_U16 },
99 	[TCA_VLAN_PUSH_VLAN_PRIORITY]	= { .type = NLA_U8 },
100 };
101 
102 static int tcf_vlan_init(struct net *net, struct nlattr *nla,
103 			 struct nlattr *est, struct tc_action **a,
104 			 int ovr, int bind, bool rtnl_held,
105 			 struct tcf_proto *tp, struct netlink_ext_ack *extack)
106 {
107 	struct tc_action_net *tn = net_generic(net, vlan_net_id);
108 	struct nlattr *tb[TCA_VLAN_MAX + 1];
109 	struct tcf_chain *goto_ch = NULL;
110 	struct tcf_vlan_params *p;
111 	struct tc_vlan *parm;
112 	struct tcf_vlan *v;
113 	int action;
114 	u16 push_vid = 0;
115 	__be16 push_proto = 0;
116 	u8 push_prio = 0;
117 	bool exists = false;
118 	int ret = 0, err;
119 	u32 index;
120 
121 	if (!nla)
122 		return -EINVAL;
123 
124 	err = nla_parse_nested_deprecated(tb, TCA_VLAN_MAX, nla, vlan_policy,
125 					  NULL);
126 	if (err < 0)
127 		return err;
128 
129 	if (!tb[TCA_VLAN_PARMS])
130 		return -EINVAL;
131 	parm = nla_data(tb[TCA_VLAN_PARMS]);
132 	index = parm->index;
133 	err = tcf_idr_check_alloc(tn, &index, a, bind);
134 	if (err < 0)
135 		return err;
136 	exists = err;
137 	if (exists && bind)
138 		return 0;
139 
140 	switch (parm->v_action) {
141 	case TCA_VLAN_ACT_POP:
142 		break;
143 	case TCA_VLAN_ACT_PUSH:
144 	case TCA_VLAN_ACT_MODIFY:
145 		if (!tb[TCA_VLAN_PUSH_VLAN_ID]) {
146 			if (exists)
147 				tcf_idr_release(*a, bind);
148 			else
149 				tcf_idr_cleanup(tn, index);
150 			return -EINVAL;
151 		}
152 		push_vid = nla_get_u16(tb[TCA_VLAN_PUSH_VLAN_ID]);
153 		if (push_vid >= VLAN_VID_MASK) {
154 			if (exists)
155 				tcf_idr_release(*a, bind);
156 			else
157 				tcf_idr_cleanup(tn, index);
158 			return -ERANGE;
159 		}
160 
161 		if (tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]) {
162 			push_proto = nla_get_be16(tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]);
163 			switch (push_proto) {
164 			case htons(ETH_P_8021Q):
165 			case htons(ETH_P_8021AD):
166 				break;
167 			default:
168 				if (exists)
169 					tcf_idr_release(*a, bind);
170 				else
171 					tcf_idr_cleanup(tn, index);
172 				return -EPROTONOSUPPORT;
173 			}
174 		} else {
175 			push_proto = htons(ETH_P_8021Q);
176 		}
177 
178 		if (tb[TCA_VLAN_PUSH_VLAN_PRIORITY])
179 			push_prio = nla_get_u8(tb[TCA_VLAN_PUSH_VLAN_PRIORITY]);
180 		break;
181 	default:
182 		if (exists)
183 			tcf_idr_release(*a, bind);
184 		else
185 			tcf_idr_cleanup(tn, index);
186 		return -EINVAL;
187 	}
188 	action = parm->v_action;
189 
190 	if (!exists) {
191 		ret = tcf_idr_create(tn, index, est, a,
192 				     &act_vlan_ops, bind, true);
193 		if (ret) {
194 			tcf_idr_cleanup(tn, index);
195 			return ret;
196 		}
197 
198 		ret = ACT_P_CREATED;
199 	} else if (!ovr) {
200 		tcf_idr_release(*a, bind);
201 		return -EEXIST;
202 	}
203 
204 	err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
205 	if (err < 0)
206 		goto release_idr;
207 
208 	v = to_vlan(*a);
209 
210 	p = kzalloc(sizeof(*p), GFP_KERNEL);
211 	if (!p) {
212 		err = -ENOMEM;
213 		goto put_chain;
214 	}
215 
216 	p->tcfv_action = action;
217 	p->tcfv_push_vid = push_vid;
218 	p->tcfv_push_prio = push_prio;
219 	p->tcfv_push_proto = push_proto;
220 
221 	spin_lock_bh(&v->tcf_lock);
222 	goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
223 	rcu_swap_protected(v->vlan_p, p, lockdep_is_held(&v->tcf_lock));
224 	spin_unlock_bh(&v->tcf_lock);
225 
226 	if (goto_ch)
227 		tcf_chain_put_by_act(goto_ch);
228 	if (p)
229 		kfree_rcu(p, rcu);
230 
231 	if (ret == ACT_P_CREATED)
232 		tcf_idr_insert(tn, *a);
233 	return ret;
234 put_chain:
235 	if (goto_ch)
236 		tcf_chain_put_by_act(goto_ch);
237 release_idr:
238 	tcf_idr_release(*a, bind);
239 	return err;
240 }
241 
242 static void tcf_vlan_cleanup(struct tc_action *a)
243 {
244 	struct tcf_vlan *v = to_vlan(a);
245 	struct tcf_vlan_params *p;
246 
247 	p = rcu_dereference_protected(v->vlan_p, 1);
248 	if (p)
249 		kfree_rcu(p, rcu);
250 }
251 
252 static int tcf_vlan_dump(struct sk_buff *skb, struct tc_action *a,
253 			 int bind, int ref)
254 {
255 	unsigned char *b = skb_tail_pointer(skb);
256 	struct tcf_vlan *v = to_vlan(a);
257 	struct tcf_vlan_params *p;
258 	struct tc_vlan opt = {
259 		.index    = v->tcf_index,
260 		.refcnt   = refcount_read(&v->tcf_refcnt) - ref,
261 		.bindcnt  = atomic_read(&v->tcf_bindcnt) - bind,
262 	};
263 	struct tcf_t t;
264 
265 	spin_lock_bh(&v->tcf_lock);
266 	opt.action = v->tcf_action;
267 	p = rcu_dereference_protected(v->vlan_p, lockdep_is_held(&v->tcf_lock));
268 	opt.v_action = p->tcfv_action;
269 	if (nla_put(skb, TCA_VLAN_PARMS, sizeof(opt), &opt))
270 		goto nla_put_failure;
271 
272 	if ((p->tcfv_action == TCA_VLAN_ACT_PUSH ||
273 	     p->tcfv_action == TCA_VLAN_ACT_MODIFY) &&
274 	    (nla_put_u16(skb, TCA_VLAN_PUSH_VLAN_ID, p->tcfv_push_vid) ||
275 	     nla_put_be16(skb, TCA_VLAN_PUSH_VLAN_PROTOCOL,
276 			  p->tcfv_push_proto) ||
277 	     (nla_put_u8(skb, TCA_VLAN_PUSH_VLAN_PRIORITY,
278 					      p->tcfv_push_prio))))
279 		goto nla_put_failure;
280 
281 	tcf_tm_dump(&t, &v->tcf_tm);
282 	if (nla_put_64bit(skb, TCA_VLAN_TM, sizeof(t), &t, TCA_VLAN_PAD))
283 		goto nla_put_failure;
284 	spin_unlock_bh(&v->tcf_lock);
285 
286 	return skb->len;
287 
288 nla_put_failure:
289 	spin_unlock_bh(&v->tcf_lock);
290 	nlmsg_trim(skb, b);
291 	return -1;
292 }
293 
294 static int tcf_vlan_walker(struct net *net, struct sk_buff *skb,
295 			   struct netlink_callback *cb, int type,
296 			   const struct tc_action_ops *ops,
297 			   struct netlink_ext_ack *extack)
298 {
299 	struct tc_action_net *tn = net_generic(net, vlan_net_id);
300 
301 	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
302 }
303 
304 static void tcf_vlan_stats_update(struct tc_action *a, u64 bytes, u32 packets,
305 				  u64 lastuse, bool hw)
306 {
307 	struct tcf_vlan *v = to_vlan(a);
308 	struct tcf_t *tm = &v->tcf_tm;
309 
310 	_bstats_cpu_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
311 	if (hw)
312 		_bstats_cpu_update(this_cpu_ptr(a->cpu_bstats_hw),
313 				   bytes, packets);
314 	tm->lastuse = max_t(u64, tm->lastuse, lastuse);
315 }
316 
317 static int tcf_vlan_search(struct net *net, struct tc_action **a, u32 index)
318 {
319 	struct tc_action_net *tn = net_generic(net, vlan_net_id);
320 
321 	return tcf_idr_search(tn, a, index);
322 }
323 
324 static size_t tcf_vlan_get_fill_size(const struct tc_action *act)
325 {
326 	return nla_total_size(sizeof(struct tc_vlan))
327 		+ nla_total_size(sizeof(u16)) /* TCA_VLAN_PUSH_VLAN_ID */
328 		+ nla_total_size(sizeof(u16)) /* TCA_VLAN_PUSH_VLAN_PROTOCOL */
329 		+ nla_total_size(sizeof(u8)); /* TCA_VLAN_PUSH_VLAN_PRIORITY */
330 }
331 
332 static struct tc_action_ops act_vlan_ops = {
333 	.kind		=	"vlan",
334 	.id		=	TCA_ID_VLAN,
335 	.owner		=	THIS_MODULE,
336 	.act		=	tcf_vlan_act,
337 	.dump		=	tcf_vlan_dump,
338 	.init		=	tcf_vlan_init,
339 	.cleanup	=	tcf_vlan_cleanup,
340 	.walk		=	tcf_vlan_walker,
341 	.stats_update	=	tcf_vlan_stats_update,
342 	.get_fill_size	=	tcf_vlan_get_fill_size,
343 	.lookup		=	tcf_vlan_search,
344 	.size		=	sizeof(struct tcf_vlan),
345 };
346 
347 static __net_init int vlan_init_net(struct net *net)
348 {
349 	struct tc_action_net *tn = net_generic(net, vlan_net_id);
350 
351 	return tc_action_net_init(net, tn, &act_vlan_ops);
352 }
353 
354 static void __net_exit vlan_exit_net(struct list_head *net_list)
355 {
356 	tc_action_net_exit(net_list, vlan_net_id);
357 }
358 
359 static struct pernet_operations vlan_net_ops = {
360 	.init = vlan_init_net,
361 	.exit_batch = vlan_exit_net,
362 	.id   = &vlan_net_id,
363 	.size = sizeof(struct tc_action_net),
364 };
365 
366 static int __init vlan_init_module(void)
367 {
368 	return tcf_register_action(&act_vlan_ops, &vlan_net_ops);
369 }
370 
371 static void __exit vlan_cleanup_module(void)
372 {
373 	tcf_unregister_action(&act_vlan_ops, &vlan_net_ops);
374 }
375 
376 module_init(vlan_init_module);
377 module_exit(vlan_cleanup_module);
378 
379 MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>");
380 MODULE_DESCRIPTION("vlan manipulation actions");
381 MODULE_LICENSE("GPL v2");
382