xref: /openbmc/linux/net/sched/act_tunnel_key.c (revision 4cff79e9)
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 static unsigned int tunnel_key_net_id;
24 static struct tc_action_ops act_tunnel_key_ops;
25 
26 static int tunnel_key_act(struct sk_buff *skb, const struct tc_action *a,
27 			  struct tcf_result *res)
28 {
29 	struct tcf_tunnel_key *t = to_tunnel_key(a);
30 	struct tcf_tunnel_key_params *params;
31 	int action;
32 
33 	rcu_read_lock();
34 
35 	params = rcu_dereference(t->params);
36 
37 	tcf_lastuse_update(&t->tcf_tm);
38 	bstats_cpu_update(this_cpu_ptr(t->common.cpu_bstats), skb);
39 	action = params->action;
40 
41 	switch (params->tcft_action) {
42 	case TCA_TUNNEL_KEY_ACT_RELEASE:
43 		skb_dst_drop(skb);
44 		break;
45 	case TCA_TUNNEL_KEY_ACT_SET:
46 		skb_dst_drop(skb);
47 		skb_dst_set(skb, dst_clone(&params->tcft_enc_metadata->dst));
48 		break;
49 	default:
50 		WARN_ONCE(1, "Bad tunnel_key action %d.\n",
51 			  params->tcft_action);
52 		break;
53 	}
54 
55 	rcu_read_unlock();
56 
57 	return action;
58 }
59 
60 static const struct nla_policy tunnel_key_policy[TCA_TUNNEL_KEY_MAX + 1] = {
61 	[TCA_TUNNEL_KEY_PARMS]	    = { .len = sizeof(struct tc_tunnel_key) },
62 	[TCA_TUNNEL_KEY_ENC_IPV4_SRC] = { .type = NLA_U32 },
63 	[TCA_TUNNEL_KEY_ENC_IPV4_DST] = { .type = NLA_U32 },
64 	[TCA_TUNNEL_KEY_ENC_IPV6_SRC] = { .len = sizeof(struct in6_addr) },
65 	[TCA_TUNNEL_KEY_ENC_IPV6_DST] = { .len = sizeof(struct in6_addr) },
66 	[TCA_TUNNEL_KEY_ENC_KEY_ID]   = { .type = NLA_U32 },
67 	[TCA_TUNNEL_KEY_ENC_DST_PORT] = {.type = NLA_U16},
68 	[TCA_TUNNEL_KEY_NO_CSUM]      = { .type = NLA_U8 },
69 };
70 
71 static int tunnel_key_init(struct net *net, struct nlattr *nla,
72 			   struct nlattr *est, struct tc_action **a,
73 			   int ovr, int bind, struct netlink_ext_ack *extack)
74 {
75 	struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
76 	struct nlattr *tb[TCA_TUNNEL_KEY_MAX + 1];
77 	struct tcf_tunnel_key_params *params_old;
78 	struct tcf_tunnel_key_params *params_new;
79 	struct metadata_dst *metadata = NULL;
80 	struct tc_tunnel_key *parm;
81 	struct tcf_tunnel_key *t;
82 	bool exists = false;
83 	__be16 dst_port = 0;
84 	__be64 key_id;
85 	__be16 flags;
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_idr_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 		flags = TUNNEL_KEY | TUNNEL_CSUM;
117 		if (tb[TCA_TUNNEL_KEY_NO_CSUM] &&
118 		    nla_get_u8(tb[TCA_TUNNEL_KEY_NO_CSUM]))
119 			flags &= ~TUNNEL_CSUM;
120 
121 		if (tb[TCA_TUNNEL_KEY_ENC_DST_PORT])
122 			dst_port = nla_get_be16(tb[TCA_TUNNEL_KEY_ENC_DST_PORT]);
123 
124 		if (tb[TCA_TUNNEL_KEY_ENC_IPV4_SRC] &&
125 		    tb[TCA_TUNNEL_KEY_ENC_IPV4_DST]) {
126 			__be32 saddr;
127 			__be32 daddr;
128 
129 			saddr = nla_get_in_addr(tb[TCA_TUNNEL_KEY_ENC_IPV4_SRC]);
130 			daddr = nla_get_in_addr(tb[TCA_TUNNEL_KEY_ENC_IPV4_DST]);
131 
132 			metadata = __ip_tun_set_dst(saddr, daddr, 0, 0,
133 						    dst_port, flags,
134 						    key_id, 0);
135 		} else if (tb[TCA_TUNNEL_KEY_ENC_IPV6_SRC] &&
136 			   tb[TCA_TUNNEL_KEY_ENC_IPV6_DST]) {
137 			struct in6_addr saddr;
138 			struct in6_addr daddr;
139 
140 			saddr = nla_get_in6_addr(tb[TCA_TUNNEL_KEY_ENC_IPV6_SRC]);
141 			daddr = nla_get_in6_addr(tb[TCA_TUNNEL_KEY_ENC_IPV6_DST]);
142 
143 			metadata = __ipv6_tun_set_dst(&saddr, &daddr, 0, 0, dst_port,
144 						      0, flags,
145 						      key_id, 0);
146 		}
147 
148 		if (!metadata) {
149 			ret = -EINVAL;
150 			goto err_out;
151 		}
152 
153 		metadata->u.tun_info.mode |= IP_TUNNEL_INFO_TX;
154 		break;
155 	default:
156 		ret = -EINVAL;
157 		goto err_out;
158 	}
159 
160 	if (!exists) {
161 		ret = tcf_idr_create(tn, parm->index, est, a,
162 				     &act_tunnel_key_ops, bind, true);
163 		if (ret)
164 			return ret;
165 
166 		ret = ACT_P_CREATED;
167 	} else {
168 		tcf_idr_release(*a, bind);
169 		if (!ovr)
170 			return -EEXIST;
171 	}
172 
173 	t = to_tunnel_key(*a);
174 
175 	ASSERT_RTNL();
176 	params_new = kzalloc(sizeof(*params_new), GFP_KERNEL);
177 	if (unlikely(!params_new)) {
178 		if (ret == ACT_P_CREATED)
179 			tcf_idr_release(*a, bind);
180 		return -ENOMEM;
181 	}
182 
183 	params_old = rtnl_dereference(t->params);
184 
185 	params_new->action = parm->action;
186 	params_new->tcft_action = parm->t_action;
187 	params_new->tcft_enc_metadata = metadata;
188 
189 	rcu_assign_pointer(t->params, params_new);
190 
191 	if (params_old)
192 		kfree_rcu(params_old, rcu);
193 
194 	if (ret == ACT_P_CREATED)
195 		tcf_idr_insert(tn, *a);
196 
197 	return ret;
198 
199 err_out:
200 	if (exists)
201 		tcf_idr_release(*a, bind);
202 	return ret;
203 }
204 
205 static void tunnel_key_release(struct tc_action *a)
206 {
207 	struct tcf_tunnel_key *t = to_tunnel_key(a);
208 	struct tcf_tunnel_key_params *params;
209 
210 	params = rcu_dereference_protected(t->params, 1);
211 	if (params) {
212 		if (params->tcft_action == TCA_TUNNEL_KEY_ACT_SET)
213 			dst_release(&params->tcft_enc_metadata->dst);
214 
215 		kfree_rcu(params, rcu);
216 	}
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 			     struct netlink_ext_ack *extack)
298 {
299 	struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
300 
301 	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
302 }
303 
304 static int tunnel_key_search(struct net *net, struct tc_action **a, u32 index,
305 			     struct netlink_ext_ack *extack)
306 {
307 	struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
308 
309 	return tcf_idr_search(tn, a, index);
310 }
311 
312 static struct tc_action_ops act_tunnel_key_ops = {
313 	.kind		=	"tunnel_key",
314 	.type		=	TCA_ACT_TUNNEL_KEY,
315 	.owner		=	THIS_MODULE,
316 	.act		=	tunnel_key_act,
317 	.dump		=	tunnel_key_dump,
318 	.init		=	tunnel_key_init,
319 	.cleanup	=	tunnel_key_release,
320 	.walk		=	tunnel_key_walker,
321 	.lookup		=	tunnel_key_search,
322 	.size		=	sizeof(struct tcf_tunnel_key),
323 };
324 
325 static __net_init int tunnel_key_init_net(struct net *net)
326 {
327 	struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
328 
329 	return tc_action_net_init(tn, &act_tunnel_key_ops);
330 }
331 
332 static void __net_exit tunnel_key_exit_net(struct list_head *net_list)
333 {
334 	tc_action_net_exit(net_list, tunnel_key_net_id);
335 }
336 
337 static struct pernet_operations tunnel_key_net_ops = {
338 	.init = tunnel_key_init_net,
339 	.exit_batch = 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