xref: /openbmc/linux/net/sched/act_vlan.c (revision 52cdded0)
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 	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 	tcf_action_inc_drop_qstats(&v->common);
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, u32 flags,
106 			 struct netlink_ext_ack *extack)
107 {
108 	struct tc_action_net *tn = net_generic(net, vlan_net_id);
109 	struct nlattr *tb[TCA_VLAN_MAX + 1];
110 	struct tcf_chain *goto_ch = NULL;
111 	struct tcf_vlan_params *p;
112 	struct tc_vlan *parm;
113 	struct tcf_vlan *v;
114 	int action;
115 	u16 push_vid = 0;
116 	__be16 push_proto = 0;
117 	u8 push_prio = 0;
118 	bool exists = false;
119 	int ret = 0, err;
120 	u32 index;
121 
122 	if (!nla)
123 		return -EINVAL;
124 
125 	err = nla_parse_nested_deprecated(tb, TCA_VLAN_MAX, nla, vlan_policy,
126 					  NULL);
127 	if (err < 0)
128 		return err;
129 
130 	if (!tb[TCA_VLAN_PARMS])
131 		return -EINVAL;
132 	parm = nla_data(tb[TCA_VLAN_PARMS]);
133 	index = parm->index;
134 	err = tcf_idr_check_alloc(tn, &index, a, bind);
135 	if (err < 0)
136 		return err;
137 	exists = err;
138 	if (exists && bind)
139 		return 0;
140 
141 	switch (parm->v_action) {
142 	case TCA_VLAN_ACT_POP:
143 		break;
144 	case TCA_VLAN_ACT_PUSH:
145 	case TCA_VLAN_ACT_MODIFY:
146 		if (!tb[TCA_VLAN_PUSH_VLAN_ID]) {
147 			if (exists)
148 				tcf_idr_release(*a, bind);
149 			else
150 				tcf_idr_cleanup(tn, index);
151 			return -EINVAL;
152 		}
153 		push_vid = nla_get_u16(tb[TCA_VLAN_PUSH_VLAN_ID]);
154 		if (push_vid >= VLAN_VID_MASK) {
155 			if (exists)
156 				tcf_idr_release(*a, bind);
157 			else
158 				tcf_idr_cleanup(tn, index);
159 			return -ERANGE;
160 		}
161 
162 		if (tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]) {
163 			push_proto = nla_get_be16(tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]);
164 			switch (push_proto) {
165 			case htons(ETH_P_8021Q):
166 			case htons(ETH_P_8021AD):
167 				break;
168 			default:
169 				if (exists)
170 					tcf_idr_release(*a, bind);
171 				else
172 					tcf_idr_cleanup(tn, index);
173 				return -EPROTONOSUPPORT;
174 			}
175 		} else {
176 			push_proto = htons(ETH_P_8021Q);
177 		}
178 
179 		if (tb[TCA_VLAN_PUSH_VLAN_PRIORITY])
180 			push_prio = nla_get_u8(tb[TCA_VLAN_PUSH_VLAN_PRIORITY]);
181 		break;
182 	default:
183 		if (exists)
184 			tcf_idr_release(*a, bind);
185 		else
186 			tcf_idr_cleanup(tn, index);
187 		return -EINVAL;
188 	}
189 	action = parm->v_action;
190 
191 	if (!exists) {
192 		ret = tcf_idr_create_from_flags(tn, index, est, a,
193 						&act_vlan_ops, bind, flags);
194 		if (ret) {
195 			tcf_idr_cleanup(tn, index);
196 			return ret;
197 		}
198 
199 		ret = ACT_P_CREATED;
200 	} else if (!ovr) {
201 		tcf_idr_release(*a, bind);
202 		return -EEXIST;
203 	}
204 
205 	err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
206 	if (err < 0)
207 		goto release_idr;
208 
209 	v = to_vlan(*a);
210 
211 	p = kzalloc(sizeof(*p), GFP_KERNEL);
212 	if (!p) {
213 		err = -ENOMEM;
214 		goto put_chain;
215 	}
216 
217 	p->tcfv_action = action;
218 	p->tcfv_push_vid = push_vid;
219 	p->tcfv_push_prio = push_prio;
220 	p->tcfv_push_proto = push_proto;
221 
222 	spin_lock_bh(&v->tcf_lock);
223 	goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
224 	p = rcu_replace_pointer(v->vlan_p, p, lockdep_is_held(&v->tcf_lock));
225 	spin_unlock_bh(&v->tcf_lock);
226 
227 	if (goto_ch)
228 		tcf_chain_put_by_act(goto_ch);
229 	if (p)
230 		kfree_rcu(p, rcu);
231 
232 	if (ret == ACT_P_CREATED)
233 		tcf_idr_insert(tn, *a);
234 	return ret;
235 put_chain:
236 	if (goto_ch)
237 		tcf_chain_put_by_act(goto_ch);
238 release_idr:
239 	tcf_idr_release(*a, bind);
240 	return err;
241 }
242 
243 static void tcf_vlan_cleanup(struct tc_action *a)
244 {
245 	struct tcf_vlan *v = to_vlan(a);
246 	struct tcf_vlan_params *p;
247 
248 	p = rcu_dereference_protected(v->vlan_p, 1);
249 	if (p)
250 		kfree_rcu(p, rcu);
251 }
252 
253 static int tcf_vlan_dump(struct sk_buff *skb, struct tc_action *a,
254 			 int bind, int ref)
255 {
256 	unsigned char *b = skb_tail_pointer(skb);
257 	struct tcf_vlan *v = to_vlan(a);
258 	struct tcf_vlan_params *p;
259 	struct tc_vlan opt = {
260 		.index    = v->tcf_index,
261 		.refcnt   = refcount_read(&v->tcf_refcnt) - ref,
262 		.bindcnt  = atomic_read(&v->tcf_bindcnt) - bind,
263 	};
264 	struct tcf_t t;
265 
266 	spin_lock_bh(&v->tcf_lock);
267 	opt.action = v->tcf_action;
268 	p = rcu_dereference_protected(v->vlan_p, lockdep_is_held(&v->tcf_lock));
269 	opt.v_action = p->tcfv_action;
270 	if (nla_put(skb, TCA_VLAN_PARMS, sizeof(opt), &opt))
271 		goto nla_put_failure;
272 
273 	if ((p->tcfv_action == TCA_VLAN_ACT_PUSH ||
274 	     p->tcfv_action == TCA_VLAN_ACT_MODIFY) &&
275 	    (nla_put_u16(skb, TCA_VLAN_PUSH_VLAN_ID, p->tcfv_push_vid) ||
276 	     nla_put_be16(skb, TCA_VLAN_PUSH_VLAN_PROTOCOL,
277 			  p->tcfv_push_proto) ||
278 	     (nla_put_u8(skb, TCA_VLAN_PUSH_VLAN_PRIORITY,
279 					      p->tcfv_push_prio))))
280 		goto nla_put_failure;
281 
282 	tcf_tm_dump(&t, &v->tcf_tm);
283 	if (nla_put_64bit(skb, TCA_VLAN_TM, sizeof(t), &t, TCA_VLAN_PAD))
284 		goto nla_put_failure;
285 	spin_unlock_bh(&v->tcf_lock);
286 
287 	return skb->len;
288 
289 nla_put_failure:
290 	spin_unlock_bh(&v->tcf_lock);
291 	nlmsg_trim(skb, b);
292 	return -1;
293 }
294 
295 static int tcf_vlan_walker(struct net *net, struct sk_buff *skb,
296 			   struct netlink_callback *cb, int type,
297 			   const struct tc_action_ops *ops,
298 			   struct netlink_ext_ack *extack)
299 {
300 	struct tc_action_net *tn = net_generic(net, vlan_net_id);
301 
302 	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
303 }
304 
305 static void tcf_vlan_stats_update(struct tc_action *a, u64 bytes, u64 packets,
306 				  u64 drops, u64 lastuse, bool hw)
307 {
308 	struct tcf_vlan *v = to_vlan(a);
309 	struct tcf_t *tm = &v->tcf_tm;
310 
311 	tcf_action_update_stats(a, bytes, packets, drops, hw);
312 	tm->lastuse = max_t(u64, tm->lastuse, lastuse);
313 }
314 
315 static int tcf_vlan_search(struct net *net, struct tc_action **a, u32 index)
316 {
317 	struct tc_action_net *tn = net_generic(net, vlan_net_id);
318 
319 	return tcf_idr_search(tn, a, index);
320 }
321 
322 static size_t tcf_vlan_get_fill_size(const struct tc_action *act)
323 {
324 	return nla_total_size(sizeof(struct tc_vlan))
325 		+ nla_total_size(sizeof(u16)) /* TCA_VLAN_PUSH_VLAN_ID */
326 		+ nla_total_size(sizeof(u16)) /* TCA_VLAN_PUSH_VLAN_PROTOCOL */
327 		+ nla_total_size(sizeof(u8)); /* TCA_VLAN_PUSH_VLAN_PRIORITY */
328 }
329 
330 static struct tc_action_ops act_vlan_ops = {
331 	.kind		=	"vlan",
332 	.id		=	TCA_ID_VLAN,
333 	.owner		=	THIS_MODULE,
334 	.act		=	tcf_vlan_act,
335 	.dump		=	tcf_vlan_dump,
336 	.init		=	tcf_vlan_init,
337 	.cleanup	=	tcf_vlan_cleanup,
338 	.walk		=	tcf_vlan_walker,
339 	.stats_update	=	tcf_vlan_stats_update,
340 	.get_fill_size	=	tcf_vlan_get_fill_size,
341 	.lookup		=	tcf_vlan_search,
342 	.size		=	sizeof(struct tcf_vlan),
343 };
344 
345 static __net_init int vlan_init_net(struct net *net)
346 {
347 	struct tc_action_net *tn = net_generic(net, vlan_net_id);
348 
349 	return tc_action_net_init(net, tn, &act_vlan_ops);
350 }
351 
352 static void __net_exit vlan_exit_net(struct list_head *net_list)
353 {
354 	tc_action_net_exit(net_list, vlan_net_id);
355 }
356 
357 static struct pernet_operations vlan_net_ops = {
358 	.init = vlan_init_net,
359 	.exit_batch = vlan_exit_net,
360 	.id   = &vlan_net_id,
361 	.size = sizeof(struct tc_action_net),
362 };
363 
364 static int __init vlan_init_module(void)
365 {
366 	return tcf_register_action(&act_vlan_ops, &vlan_net_ops);
367 }
368 
369 static void __exit vlan_cleanup_module(void)
370 {
371 	tcf_unregister_action(&act_vlan_ops, &vlan_net_ops);
372 }
373 
374 module_init(vlan_init_module);
375 module_exit(vlan_cleanup_module);
376 
377 MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>");
378 MODULE_DESCRIPTION("vlan manipulation actions");
379 MODULE_LICENSE("GPL v2");
380