xref: /openbmc/linux/net/sched/act_tunnel_key.c (revision a36954f5)
1 /*
2  * Copyright (c) 2016, Amir Vadai <amir@vadai.me>
3  * Copyright (c) 2016, Mellanox Technologies. All rights reserved.
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  */
10 
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/skbuff.h>
15 #include <linux/rtnetlink.h>
16 #include <net/netlink.h>
17 #include <net/pkt_sched.h>
18 #include <net/dst.h>
19 
20 #include <linux/tc_act/tc_tunnel_key.h>
21 #include <net/tc_act/tc_tunnel_key.h>
22 
23 #define TUNNEL_KEY_TAB_MASK     15
24 
25 static unsigned int tunnel_key_net_id;
26 static struct tc_action_ops act_tunnel_key_ops;
27 
28 static int tunnel_key_act(struct sk_buff *skb, const struct tc_action *a,
29 			  struct tcf_result *res)
30 {
31 	struct tcf_tunnel_key *t = to_tunnel_key(a);
32 	struct tcf_tunnel_key_params *params;
33 	int action;
34 
35 	rcu_read_lock();
36 
37 	params = rcu_dereference(t->params);
38 
39 	tcf_lastuse_update(&t->tcf_tm);
40 	bstats_cpu_update(this_cpu_ptr(t->common.cpu_bstats), skb);
41 	action = params->action;
42 
43 	switch (params->tcft_action) {
44 	case TCA_TUNNEL_KEY_ACT_RELEASE:
45 		skb_dst_drop(skb);
46 		break;
47 	case TCA_TUNNEL_KEY_ACT_SET:
48 		skb_dst_drop(skb);
49 		skb_dst_set(skb, dst_clone(&params->tcft_enc_metadata->dst));
50 		break;
51 	default:
52 		WARN_ONCE(1, "Bad tunnel_key action %d.\n",
53 			  params->tcft_action);
54 		break;
55 	}
56 
57 	rcu_read_unlock();
58 
59 	return action;
60 }
61 
62 static const struct nla_policy tunnel_key_policy[TCA_TUNNEL_KEY_MAX + 1] = {
63 	[TCA_TUNNEL_KEY_PARMS]	    = { .len = sizeof(struct tc_tunnel_key) },
64 	[TCA_TUNNEL_KEY_ENC_IPV4_SRC] = { .type = NLA_U32 },
65 	[TCA_TUNNEL_KEY_ENC_IPV4_DST] = { .type = NLA_U32 },
66 	[TCA_TUNNEL_KEY_ENC_IPV6_SRC] = { .len = sizeof(struct in6_addr) },
67 	[TCA_TUNNEL_KEY_ENC_IPV6_DST] = { .len = sizeof(struct in6_addr) },
68 	[TCA_TUNNEL_KEY_ENC_KEY_ID]   = { .type = NLA_U32 },
69 	[TCA_TUNNEL_KEY_ENC_DST_PORT] = {.type = NLA_U16},
70 };
71 
72 static int tunnel_key_init(struct net *net, struct nlattr *nla,
73 			   struct nlattr *est, struct tc_action **a,
74 			   int ovr, int bind)
75 {
76 	struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
77 	struct nlattr *tb[TCA_TUNNEL_KEY_MAX + 1];
78 	struct tcf_tunnel_key_params *params_old;
79 	struct tcf_tunnel_key_params *params_new;
80 	struct metadata_dst *metadata = NULL;
81 	struct tc_tunnel_key *parm;
82 	struct tcf_tunnel_key *t;
83 	bool exists = false;
84 	__be16 dst_port = 0;
85 	__be64 key_id;
86 	int ret = 0;
87 	int err;
88 
89 	if (!nla)
90 		return -EINVAL;
91 
92 	err = nla_parse_nested(tb, TCA_TUNNEL_KEY_MAX, nla, tunnel_key_policy,
93 			       NULL);
94 	if (err < 0)
95 		return err;
96 
97 	if (!tb[TCA_TUNNEL_KEY_PARMS])
98 		return -EINVAL;
99 
100 	parm = nla_data(tb[TCA_TUNNEL_KEY_PARMS]);
101 	exists = tcf_hash_check(tn, parm->index, a, bind);
102 	if (exists && bind)
103 		return 0;
104 
105 	switch (parm->t_action) {
106 	case TCA_TUNNEL_KEY_ACT_RELEASE:
107 		break;
108 	case TCA_TUNNEL_KEY_ACT_SET:
109 		if (!tb[TCA_TUNNEL_KEY_ENC_KEY_ID]) {
110 			ret = -EINVAL;
111 			goto err_out;
112 		}
113 
114 		key_id = key32_to_tunnel_id(nla_get_be32(tb[TCA_TUNNEL_KEY_ENC_KEY_ID]));
115 
116 		if (tb[TCA_TUNNEL_KEY_ENC_DST_PORT])
117 			dst_port = nla_get_be16(tb[TCA_TUNNEL_KEY_ENC_DST_PORT]);
118 
119 		if (tb[TCA_TUNNEL_KEY_ENC_IPV4_SRC] &&
120 		    tb[TCA_TUNNEL_KEY_ENC_IPV4_DST]) {
121 			__be32 saddr;
122 			__be32 daddr;
123 
124 			saddr = nla_get_in_addr(tb[TCA_TUNNEL_KEY_ENC_IPV4_SRC]);
125 			daddr = nla_get_in_addr(tb[TCA_TUNNEL_KEY_ENC_IPV4_DST]);
126 
127 			metadata = __ip_tun_set_dst(saddr, daddr, 0, 0,
128 						    dst_port, TUNNEL_KEY,
129 						    key_id, 0);
130 		} else if (tb[TCA_TUNNEL_KEY_ENC_IPV6_SRC] &&
131 			   tb[TCA_TUNNEL_KEY_ENC_IPV6_DST]) {
132 			struct in6_addr saddr;
133 			struct in6_addr daddr;
134 
135 			saddr = nla_get_in6_addr(tb[TCA_TUNNEL_KEY_ENC_IPV6_SRC]);
136 			daddr = nla_get_in6_addr(tb[TCA_TUNNEL_KEY_ENC_IPV6_DST]);
137 
138 			metadata = __ipv6_tun_set_dst(&saddr, &daddr, 0, 0, dst_port,
139 						      0, TUNNEL_KEY,
140 						      key_id, 0);
141 		}
142 
143 		if (!metadata) {
144 			ret = -EINVAL;
145 			goto err_out;
146 		}
147 
148 		metadata->u.tun_info.mode |= IP_TUNNEL_INFO_TX;
149 		break;
150 	default:
151 		goto err_out;
152 	}
153 
154 	if (!exists) {
155 		ret = tcf_hash_create(tn, parm->index, est, a,
156 				      &act_tunnel_key_ops, bind, true);
157 		if (ret)
158 			return ret;
159 
160 		ret = ACT_P_CREATED;
161 	} else {
162 		tcf_hash_release(*a, bind);
163 		if (!ovr)
164 			return -EEXIST;
165 	}
166 
167 	t = to_tunnel_key(*a);
168 
169 	ASSERT_RTNL();
170 	params_new = kzalloc(sizeof(*params_new), GFP_KERNEL);
171 	if (unlikely(!params_new)) {
172 		if (ret == ACT_P_CREATED)
173 			tcf_hash_release(*a, bind);
174 		return -ENOMEM;
175 	}
176 
177 	params_old = rtnl_dereference(t->params);
178 
179 	params_new->action = parm->action;
180 	params_new->tcft_action = parm->t_action;
181 	params_new->tcft_enc_metadata = metadata;
182 
183 	rcu_assign_pointer(t->params, params_new);
184 
185 	if (params_old)
186 		kfree_rcu(params_old, rcu);
187 
188 	if (ret == ACT_P_CREATED)
189 		tcf_hash_insert(tn, *a);
190 
191 	return ret;
192 
193 err_out:
194 	if (exists)
195 		tcf_hash_release(*a, bind);
196 	return ret;
197 }
198 
199 static void tunnel_key_release(struct tc_action *a, int bind)
200 {
201 	struct tcf_tunnel_key *t = to_tunnel_key(a);
202 	struct tcf_tunnel_key_params *params;
203 
204 	params = rcu_dereference_protected(t->params, 1);
205 
206 	if (params->tcft_action == TCA_TUNNEL_KEY_ACT_SET)
207 		dst_release(&params->tcft_enc_metadata->dst);
208 
209 	kfree_rcu(params, rcu);
210 }
211 
212 static int tunnel_key_dump_addresses(struct sk_buff *skb,
213 				     const struct ip_tunnel_info *info)
214 {
215 	unsigned short family = ip_tunnel_info_af(info);
216 
217 	if (family == AF_INET) {
218 		__be32 saddr = info->key.u.ipv4.src;
219 		__be32 daddr = info->key.u.ipv4.dst;
220 
221 		if (!nla_put_in_addr(skb, TCA_TUNNEL_KEY_ENC_IPV4_SRC, saddr) &&
222 		    !nla_put_in_addr(skb, TCA_TUNNEL_KEY_ENC_IPV4_DST, daddr))
223 			return 0;
224 	}
225 
226 	if (family == AF_INET6) {
227 		const struct in6_addr *saddr6 = &info->key.u.ipv6.src;
228 		const struct in6_addr *daddr6 = &info->key.u.ipv6.dst;
229 
230 		if (!nla_put_in6_addr(skb,
231 				      TCA_TUNNEL_KEY_ENC_IPV6_SRC, saddr6) &&
232 		    !nla_put_in6_addr(skb,
233 				      TCA_TUNNEL_KEY_ENC_IPV6_DST, daddr6))
234 			return 0;
235 	}
236 
237 	return -EINVAL;
238 }
239 
240 static int tunnel_key_dump(struct sk_buff *skb, struct tc_action *a,
241 			   int bind, int ref)
242 {
243 	unsigned char *b = skb_tail_pointer(skb);
244 	struct tcf_tunnel_key *t = to_tunnel_key(a);
245 	struct tcf_tunnel_key_params *params;
246 	struct tc_tunnel_key opt = {
247 		.index    = t->tcf_index,
248 		.refcnt   = t->tcf_refcnt - ref,
249 		.bindcnt  = t->tcf_bindcnt - bind,
250 	};
251 	struct tcf_t tm;
252 
253 	params = rtnl_dereference(t->params);
254 
255 	opt.t_action = params->tcft_action;
256 	opt.action = params->action;
257 
258 	if (nla_put(skb, TCA_TUNNEL_KEY_PARMS, sizeof(opt), &opt))
259 		goto nla_put_failure;
260 
261 	if (params->tcft_action == TCA_TUNNEL_KEY_ACT_SET) {
262 		struct ip_tunnel_key *key =
263 			&params->tcft_enc_metadata->u.tun_info.key;
264 		__be32 key_id = tunnel_id_to_key32(key->tun_id);
265 
266 		if (nla_put_be32(skb, TCA_TUNNEL_KEY_ENC_KEY_ID, key_id) ||
267 		    tunnel_key_dump_addresses(skb,
268 					      &params->tcft_enc_metadata->u.tun_info) ||
269 		    nla_put_be16(skb, TCA_TUNNEL_KEY_ENC_DST_PORT, key->tp_dst))
270 			goto nla_put_failure;
271 	}
272 
273 	tcf_tm_dump(&tm, &t->tcf_tm);
274 	if (nla_put_64bit(skb, TCA_TUNNEL_KEY_TM, sizeof(tm),
275 			  &tm, TCA_TUNNEL_KEY_PAD))
276 		goto nla_put_failure;
277 
278 	return skb->len;
279 
280 nla_put_failure:
281 	nlmsg_trim(skb, b);
282 	return -1;
283 }
284 
285 static int tunnel_key_walker(struct net *net, struct sk_buff *skb,
286 			     struct netlink_callback *cb, int type,
287 			     const struct tc_action_ops *ops)
288 {
289 	struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
290 
291 	return tcf_generic_walker(tn, skb, cb, type, ops);
292 }
293 
294 static int tunnel_key_search(struct net *net, struct tc_action **a, u32 index)
295 {
296 	struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
297 
298 	return tcf_hash_search(tn, a, index);
299 }
300 
301 static struct tc_action_ops act_tunnel_key_ops = {
302 	.kind		=	"tunnel_key",
303 	.type		=	TCA_ACT_TUNNEL_KEY,
304 	.owner		=	THIS_MODULE,
305 	.act		=	tunnel_key_act,
306 	.dump		=	tunnel_key_dump,
307 	.init		=	tunnel_key_init,
308 	.cleanup	=	tunnel_key_release,
309 	.walk		=	tunnel_key_walker,
310 	.lookup		=	tunnel_key_search,
311 	.size		=	sizeof(struct tcf_tunnel_key),
312 };
313 
314 static __net_init int tunnel_key_init_net(struct net *net)
315 {
316 	struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
317 
318 	return tc_action_net_init(tn, &act_tunnel_key_ops, TUNNEL_KEY_TAB_MASK);
319 }
320 
321 static void __net_exit tunnel_key_exit_net(struct net *net)
322 {
323 	struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
324 
325 	tc_action_net_exit(tn);
326 }
327 
328 static struct pernet_operations tunnel_key_net_ops = {
329 	.init = tunnel_key_init_net,
330 	.exit = tunnel_key_exit_net,
331 	.id   = &tunnel_key_net_id,
332 	.size = sizeof(struct tc_action_net),
333 };
334 
335 static int __init tunnel_key_init_module(void)
336 {
337 	return tcf_register_action(&act_tunnel_key_ops, &tunnel_key_net_ops);
338 }
339 
340 static void __exit tunnel_key_cleanup_module(void)
341 {
342 	tcf_unregister_action(&act_tunnel_key_ops, &tunnel_key_net_ops);
343 }
344 
345 module_init(tunnel_key_init_module);
346 module_exit(tunnel_key_cleanup_module);
347 
348 MODULE_AUTHOR("Amir Vadai <amir@vadai.me>");
349 MODULE_DESCRIPTION("ip tunnel manipulation actions");
350 MODULE_LICENSE("GPL v2");
351