net/sched/act_tunnel_key.c

   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
  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(&params->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
  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                 goto err_out;
 145         }
 146
 147         if (!exists) {
 148                 ret = tcf_hash_create(tn, parm->index, est, a,
 149                                       &act_tunnel_key_ops, bind, true);
 150                 if (ret)
 151                         return ret;
 152
 153                 ret = ACT_P_CREATED;
 154         } else {
 155                 tcf_hash_release(*a, bind);
 156                 if (!ovr)
 157                         return -EEXIST;
 158         }
 159
 160         t = to_tunnel_key(*a);
 161
 162         ASSERT_RTNL();
 163         params_new = kzalloc(sizeof(*params_new), GFP_KERNEL);
 164         if (unlikely(!params_new)) {
 165                 if (ret == ACT_P_CREATED)
 166                         tcf_hash_release(*a, bind);
 167                 return -ENOMEM;
 168         }
 169
 170         params_old = rtnl_dereference(t->params);
 171
 172         params_new->action = parm->action;
 173         params_new->tcft_action = parm->t_action;
 174         params_new->tcft_enc_metadata = metadata;
 175
 176         rcu_assign_pointer(t->params, params_new);
 177
 178         if (params_old)
 179                 kfree_rcu(params_old, rcu);
 180
 181         if (ret == ACT_P_CREATED)
 182                 tcf_hash_insert(tn, *a);
 183
 184         return ret;
 185
 186 err_out:
 187         if (exists)
 188                 tcf_hash_release(*a, bind);
 189         return ret;
 190 }
 191
 192 static void tunnel_key_release(struct tc_action *a, int bind)
 193 {
 194         struct tcf_tunnel_key *t = to_tunnel_key(a);
 195         struct tcf_tunnel_key_params *params;
 196
 197         params = rcu_dereference_protected(t->params, 1);
 198
 199         if (params->tcft_action == TCA_TUNNEL_KEY_ACT_SET)
 200                 dst_release(&params->tcft_enc_metadata->dst);
 201
 202         kfree_rcu(params, rcu);
 203 }
 204
 205 static int tunnel_key_dump_addresses(struct sk_buff *skb,
 206                                      const struct ip_tunnel_info *info)
 207 {
 208         unsigned short family = ip_tunnel_info_af(info);
 209
 210         if (family == AF_INET) {
 211                 __be32 saddr = info->key.u.ipv4.src;
 212                 __be32 daddr = info->key.u.ipv4.dst;
 213
 214                 if (!nla_put_in_addr(skb, TCA_TUNNEL_KEY_ENC_IPV4_SRC, saddr) &&
 215                     !nla_put_in_addr(skb, TCA_TUNNEL_KEY_ENC_IPV4_DST, daddr))
 216                         return 0;
 217         }
 218
 219         if (family == AF_INET6) {
 220                 const struct in6_addr *saddr6 = &info->key.u.ipv6.src;
 221                 const struct in6_addr *daddr6 = &info->key.u.ipv6.dst;
 222
 223                 if (!nla_put_in6_addr(skb,
 224                                       TCA_TUNNEL_KEY_ENC_IPV6_SRC, saddr6) &&
 225                     !nla_put_in6_addr(skb,
 226                                       TCA_TUNNEL_KEY_ENC_IPV6_DST, daddr6))
 227                         return 0;
 228         }
 229
 230         return -EINVAL;
 231 }
 232
 233 static int tunnel_key_dump(struct sk_buff *skb, struct tc_action *a,
 234                            int bind, int ref)
 235 {
 236         unsigned char *b = skb_tail_pointer(skb);
 237         struct tcf_tunnel_key *t = to_tunnel_key(a);
 238         struct tcf_tunnel_key_params *params;
 239         struct tc_tunnel_key opt = {
 240                 .index    = t->tcf_index,
 241                 .refcnt   = t->tcf_refcnt - ref,
 242                 .bindcnt  = t->tcf_bindcnt - bind,
 243         };
 244         struct tcf_t tm;
 245
 246         params = rtnl_dereference(t->params);
 247
 248         opt.t_action = params->tcft_action;
 249         opt.action = params->action;
 250
 251         if (nla_put(skb, TCA_TUNNEL_KEY_PARMS, sizeof(opt), &opt))
 252                 goto nla_put_failure;
 253
 254         if (params->tcft_action == TCA_TUNNEL_KEY_ACT_SET) {
 255                 struct ip_tunnel_key *key =
 256                         &params->tcft_enc_metadata->u.tun_info.key;
 257                 __be32 key_id = tunnel_id_to_key32(key->tun_id);
 258
 259                 if (nla_put_be32(skb, TCA_TUNNEL_KEY_ENC_KEY_ID, key_id) ||
 260                     tunnel_key_dump_addresses(skb,
 261                                               &params->tcft_enc_metadata->u.tun_info))
 262                         goto nla_put_failure;
 263         }
 264
 265         tcf_tm_dump(&tm, &t->tcf_tm);
 266         if (nla_put_64bit(skb, TCA_TUNNEL_KEY_TM, sizeof(tm),
 267                           &tm, TCA_TUNNEL_KEY_PAD))
 268                 goto nla_put_failure;
 269
 270         return skb->len;
 271
 272 nla_put_failure:
 273         nlmsg_trim(skb, b);
 274         return -1;
 275 }
 276
 277 static int tunnel_key_walker(struct net *net, struct sk_buff *skb,
 278                              struct netlink_callback *cb, int type,
 279                              const struct tc_action_ops *ops)
 280 {
 281         struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
 282
 283         return tcf_generic_walker(tn, skb, cb, type, ops);
 284 }
 285
 286 static int tunnel_key_search(struct net *net, struct tc_action **a, u32 index)
 287 {
 288         struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
 289
 290         return tcf_hash_search(tn, a, index);
 291 }
 292
 293 static struct tc_action_ops act_tunnel_key_ops = {
 294         .kind           =       "tunnel_key",
 295         .type           =       TCA_ACT_TUNNEL_KEY,
 296         .owner          =       THIS_MODULE,
 297         .act            =       tunnel_key_act,
 298         .dump           =       tunnel_key_dump,
 299         .init           =       tunnel_key_init,
 300         .cleanup        =       tunnel_key_release,
 301         .walk           =       tunnel_key_walker,
 302         .lookup         =       tunnel_key_search,
 303         .size           =       sizeof(struct tcf_tunnel_key),
 304 };
 305
 306 static __net_init int tunnel_key_init_net(struct net *net)
 307 {
 308         struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
 309
 310         return tc_action_net_init(tn, &act_tunnel_key_ops, TUNNEL_KEY_TAB_MASK);
 311 }
 312
 313 static void __net_exit tunnel_key_exit_net(struct net *net)
 314 {
 315         struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
 316
 317         tc_action_net_exit(tn);
 318 }
 319
 320 static struct pernet_operations tunnel_key_net_ops = {
 321         .init = tunnel_key_init_net,
 322         .exit = tunnel_key_exit_net,
 323         .id   = &tunnel_key_net_id,
 324         .size = sizeof(struct tc_action_net),
 325 };
 326
 327 static int __init tunnel_key_init_module(void)
 328 {
 329         return tcf_register_action(&act_tunnel_key_ops, &tunnel_key_net_ops);
 330 }
 331
 332 static void __exit tunnel_key_cleanup_module(void)
 333 {
 334         tcf_unregister_action(&act_tunnel_key_ops, &tunnel_key_net_ops);
 335 }
 336
 337 module_init(tunnel_key_init_module);
 338 module_exit(tunnel_key_cleanup_module);
 339
 340 MODULE_AUTHOR("Amir Vadai <amir@vadai.me>");
 341 MODULE_DESCRIPTION("ip tunnel manipulation actions");
 342 MODULE_LICENSE("GPL v2");