xref: /openbmc/linux/net/sched/act_tunnel_key.c (revision a977d045)
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 	[TCA_TUNNEL_KEY_NO_CSUM]      = { .type = NLA_U8 },
71 };
72 
73 static int tunnel_key_init(struct net *net, struct nlattr *nla,
74 			   struct nlattr *est, struct tc_action **a,
75 			   int ovr, int bind)
76 {
77 	struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
78 	struct nlattr *tb[TCA_TUNNEL_KEY_MAX + 1];
79 	struct tcf_tunnel_key_params *params_old;
80 	struct tcf_tunnel_key_params *params_new;
81 	struct metadata_dst *metadata = NULL;
82 	struct tc_tunnel_key *parm;
83 	struct tcf_tunnel_key *t;
84 	bool exists = false;
85 	__be16 dst_port = 0;
86 	__be64 key_id;
87 	__be16 flags;
88 	int ret = 0;
89 	int err;
90 
91 	if (!nla)
92 		return -EINVAL;
93 
94 	err = nla_parse_nested(tb, TCA_TUNNEL_KEY_MAX, nla, tunnel_key_policy,
95 			       NULL);
96 	if (err < 0)
97 		return err;
98 
99 	if (!tb[TCA_TUNNEL_KEY_PARMS])
100 		return -EINVAL;
101 
102 	parm = nla_data(tb[TCA_TUNNEL_KEY_PARMS]);
103 	exists = tcf_hash_check(tn, parm->index, a, bind);
104 	if (exists && bind)
105 		return 0;
106 
107 	switch (parm->t_action) {
108 	case TCA_TUNNEL_KEY_ACT_RELEASE:
109 		break;
110 	case TCA_TUNNEL_KEY_ACT_SET:
111 		if (!tb[TCA_TUNNEL_KEY_ENC_KEY_ID]) {
112 			ret = -EINVAL;
113 			goto err_out;
114 		}
115 
116 		key_id = key32_to_tunnel_id(nla_get_be32(tb[TCA_TUNNEL_KEY_ENC_KEY_ID]));
117 
118 		flags = TUNNEL_KEY | TUNNEL_CSUM;
119 		if (tb[TCA_TUNNEL_KEY_NO_CSUM] &&
120 		    nla_get_u8(tb[TCA_TUNNEL_KEY_NO_CSUM]))
121 			flags &= ~TUNNEL_CSUM;
122 
123 		if (tb[TCA_TUNNEL_KEY_ENC_DST_PORT])
124 			dst_port = nla_get_be16(tb[TCA_TUNNEL_KEY_ENC_DST_PORT]);
125 
126 		if (tb[TCA_TUNNEL_KEY_ENC_IPV4_SRC] &&
127 		    tb[TCA_TUNNEL_KEY_ENC_IPV4_DST]) {
128 			__be32 saddr;
129 			__be32 daddr;
130 
131 			saddr = nla_get_in_addr(tb[TCA_TUNNEL_KEY_ENC_IPV4_SRC]);
132 			daddr = nla_get_in_addr(tb[TCA_TUNNEL_KEY_ENC_IPV4_DST]);
133 
134 			metadata = __ip_tun_set_dst(saddr, daddr, 0, 0,
135 						    dst_port, flags,
136 						    key_id, 0);
137 		} else if (tb[TCA_TUNNEL_KEY_ENC_IPV6_SRC] &&
138 			   tb[TCA_TUNNEL_KEY_ENC_IPV6_DST]) {
139 			struct in6_addr saddr;
140 			struct in6_addr daddr;
141 
142 			saddr = nla_get_in6_addr(tb[TCA_TUNNEL_KEY_ENC_IPV6_SRC]);
143 			daddr = nla_get_in6_addr(tb[TCA_TUNNEL_KEY_ENC_IPV6_DST]);
144 
145 			metadata = __ipv6_tun_set_dst(&saddr, &daddr, 0, 0, dst_port,
146 						      0, flags,
147 						      key_id, 0);
148 		}
149 
150 		if (!metadata) {
151 			ret = -EINVAL;
152 			goto err_out;
153 		}
154 
155 		metadata->u.tun_info.mode |= IP_TUNNEL_INFO_TX;
156 		break;
157 	default:
158 		goto err_out;
159 	}
160 
161 	if (!exists) {
162 		ret = tcf_hash_create(tn, parm->index, est, a,
163 				      &act_tunnel_key_ops, bind, true);
164 		if (ret)
165 			return ret;
166 
167 		ret = ACT_P_CREATED;
168 	} else {
169 		tcf_hash_release(*a, bind);
170 		if (!ovr)
171 			return -EEXIST;
172 	}
173 
174 	t = to_tunnel_key(*a);
175 
176 	ASSERT_RTNL();
177 	params_new = kzalloc(sizeof(*params_new), GFP_KERNEL);
178 	if (unlikely(!params_new)) {
179 		if (ret == ACT_P_CREATED)
180 			tcf_hash_release(*a, bind);
181 		return -ENOMEM;
182 	}
183 
184 	params_old = rtnl_dereference(t->params);
185 
186 	params_new->action = parm->action;
187 	params_new->tcft_action = parm->t_action;
188 	params_new->tcft_enc_metadata = metadata;
189 
190 	rcu_assign_pointer(t->params, params_new);
191 
192 	if (params_old)
193 		kfree_rcu(params_old, rcu);
194 
195 	if (ret == ACT_P_CREATED)
196 		tcf_hash_insert(tn, *a);
197 
198 	return ret;
199 
200 err_out:
201 	if (exists)
202 		tcf_hash_release(*a, bind);
203 	return ret;
204 }
205 
206 static void tunnel_key_release(struct tc_action *a, int bind)
207 {
208 	struct tcf_tunnel_key *t = to_tunnel_key(a);
209 	struct tcf_tunnel_key_params *params;
210 
211 	params = rcu_dereference_protected(t->params, 1);
212 
213 	if (params->tcft_action == TCA_TUNNEL_KEY_ACT_SET)
214 		dst_release(&params->tcft_enc_metadata->dst);
215 
216 	kfree_rcu(params, rcu);
217 }
218 
219 static int tunnel_key_dump_addresses(struct sk_buff *skb,
220 				     const struct ip_tunnel_info *info)
221 {
222 	unsigned short family = ip_tunnel_info_af(info);
223 
224 	if (family == AF_INET) {
225 		__be32 saddr = info->key.u.ipv4.src;
226 		__be32 daddr = info->key.u.ipv4.dst;
227 
228 		if (!nla_put_in_addr(skb, TCA_TUNNEL_KEY_ENC_IPV4_SRC, saddr) &&
229 		    !nla_put_in_addr(skb, TCA_TUNNEL_KEY_ENC_IPV4_DST, daddr))
230 			return 0;
231 	}
232 
233 	if (family == AF_INET6) {
234 		const struct in6_addr *saddr6 = &info->key.u.ipv6.src;
235 		const struct in6_addr *daddr6 = &info->key.u.ipv6.dst;
236 
237 		if (!nla_put_in6_addr(skb,
238 				      TCA_TUNNEL_KEY_ENC_IPV6_SRC, saddr6) &&
239 		    !nla_put_in6_addr(skb,
240 				      TCA_TUNNEL_KEY_ENC_IPV6_DST, daddr6))
241 			return 0;
242 	}
243 
244 	return -EINVAL;
245 }
246 
247 static int tunnel_key_dump(struct sk_buff *skb, struct tc_action *a,
248 			   int bind, int ref)
249 {
250 	unsigned char *b = skb_tail_pointer(skb);
251 	struct tcf_tunnel_key *t = to_tunnel_key(a);
252 	struct tcf_tunnel_key_params *params;
253 	struct tc_tunnel_key opt = {
254 		.index    = t->tcf_index,
255 		.refcnt   = t->tcf_refcnt - ref,
256 		.bindcnt  = t->tcf_bindcnt - bind,
257 	};
258 	struct tcf_t tm;
259 
260 	params = rtnl_dereference(t->params);
261 
262 	opt.t_action = params->tcft_action;
263 	opt.action = params->action;
264 
265 	if (nla_put(skb, TCA_TUNNEL_KEY_PARMS, sizeof(opt), &opt))
266 		goto nla_put_failure;
267 
268 	if (params->tcft_action == TCA_TUNNEL_KEY_ACT_SET) {
269 		struct ip_tunnel_key *key =
270 			&params->tcft_enc_metadata->u.tun_info.key;
271 		__be32 key_id = tunnel_id_to_key32(key->tun_id);
272 
273 		if (nla_put_be32(skb, TCA_TUNNEL_KEY_ENC_KEY_ID, key_id) ||
274 		    tunnel_key_dump_addresses(skb,
275 					      &params->tcft_enc_metadata->u.tun_info) ||
276 		    nla_put_be16(skb, TCA_TUNNEL_KEY_ENC_DST_PORT, key->tp_dst) ||
277 		    nla_put_u8(skb, TCA_TUNNEL_KEY_NO_CSUM,
278 			       !(key->tun_flags & TUNNEL_CSUM)))
279 			goto nla_put_failure;
280 	}
281 
282 	tcf_tm_dump(&tm, &t->tcf_tm);
283 	if (nla_put_64bit(skb, TCA_TUNNEL_KEY_TM, sizeof(tm),
284 			  &tm, TCA_TUNNEL_KEY_PAD))
285 		goto nla_put_failure;
286 
287 	return skb->len;
288 
289 nla_put_failure:
290 	nlmsg_trim(skb, b);
291 	return -1;
292 }
293 
294 static int tunnel_key_walker(struct net *net, struct sk_buff *skb,
295 			     struct netlink_callback *cb, int type,
296 			     const struct tc_action_ops *ops)
297 {
298 	struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
299 
300 	return tcf_generic_walker(tn, skb, cb, type, ops);
301 }
302 
303 static int tunnel_key_search(struct net *net, struct tc_action **a, u32 index)
304 {
305 	struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
306 
307 	return tcf_hash_search(tn, a, index);
308 }
309 
310 static struct tc_action_ops act_tunnel_key_ops = {
311 	.kind		=	"tunnel_key",
312 	.type		=	TCA_ACT_TUNNEL_KEY,
313 	.owner		=	THIS_MODULE,
314 	.act		=	tunnel_key_act,
315 	.dump		=	tunnel_key_dump,
316 	.init		=	tunnel_key_init,
317 	.cleanup	=	tunnel_key_release,
318 	.walk		=	tunnel_key_walker,
319 	.lookup		=	tunnel_key_search,
320 	.size		=	sizeof(struct tcf_tunnel_key),
321 };
322 
323 static __net_init int tunnel_key_init_net(struct net *net)
324 {
325 	struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
326 
327 	return tc_action_net_init(tn, &act_tunnel_key_ops, TUNNEL_KEY_TAB_MASK);
328 }
329 
330 static void __net_exit tunnel_key_exit_net(struct net *net)
331 {
332 	struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
333 
334 	tc_action_net_exit(tn);
335 }
336 
337 static struct pernet_operations tunnel_key_net_ops = {
338 	.init = tunnel_key_init_net,
339 	.exit = tunnel_key_exit_net,
340 	.id   = &tunnel_key_net_id,
341 	.size = sizeof(struct tc_action_net),
342 };
343 
344 static int __init tunnel_key_init_module(void)
345 {
346 	return tcf_register_action(&act_tunnel_key_ops, &tunnel_key_net_ops);
347 }
348 
349 static void __exit tunnel_key_cleanup_module(void)
350 {
351 	tcf_unregister_action(&act_tunnel_key_ops, &tunnel_key_net_ops);
352 }
353 
354 module_init(tunnel_key_init_module);
355 module_exit(tunnel_key_cleanup_module);
356 
357 MODULE_AUTHOR("Amir Vadai <amir@vadai.me>");
358 MODULE_DESCRIPTION("ip tunnel manipulation actions");
359 MODULE_LICENSE("GPL v2");
360