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