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
  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)
  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                 goto err_out;
 157         }
 158
 159         if (!exists) {
 160                 ret = tcf_idr_create(tn, parm->index, est, a,
 161                                      &act_tunnel_key_ops, bind, true);
 162                 if (ret)
 163                         return ret;
 164
 165                 ret = ACT_P_CREATED;
 166         } else {
 167                 tcf_idr_release(*a, bind);
 168                 if (!ovr)
 169                         return -EEXIST;
 170         }
 171
 172         t = to_tunnel_key(*a);
 173
 174         ASSERT_RTNL();
 175         params_new = kzalloc(sizeof(*params_new), GFP_KERNEL);
 176         if (unlikely(!params_new)) {
 177                 if (ret == ACT_P_CREATED)
 178                         tcf_idr_release(*a, bind);
 179                 return -ENOMEM;
 180         }
 181
 182         params_old = rtnl_dereference(t->params);
 183
 184         params_new->action = parm->action;
 185         params_new->tcft_action = parm->t_action;
 186         params_new->tcft_enc_metadata = metadata;
 187
 188         rcu_assign_pointer(t->params, params_new);
 189
 190         if (params_old)
 191                 kfree_rcu(params_old, rcu);
 192
 193         if (ret == ACT_P_CREATED)
 194                 tcf_idr_insert(tn, *a);
 195
 196         return ret;
 197
 198 err_out:
 199         if (exists)
 200                 tcf_idr_release(*a, bind);
 201         return ret;
 202 }
 203
 204 static void tunnel_key_release(struct tc_action *a)
 205 {
 206         struct tcf_tunnel_key *t = to_tunnel_key(a);
 207         struct tcf_tunnel_key_params *params;
 208
 209         params = rcu_dereference_protected(t->params, 1);
 210
 211         if (params->tcft_action == TCA_TUNNEL_KEY_ACT_SET)
 212                 dst_release(&params->tcft_enc_metadata->dst);
 213
 214         kfree_rcu(params, rcu);
 215 }
 216
 217 static int tunnel_key_dump_addresses(struct sk_buff *skb,
 218                                      const struct ip_tunnel_info *info)
 219 {
 220         unsigned short family = ip_tunnel_info_af(info);
 221
 222         if (family == AF_INET) {
 223                 __be32 saddr = info->key.u.ipv4.src;
 224                 __be32 daddr = info->key.u.ipv4.dst;
 225
 226                 if (!nla_put_in_addr(skb, TCA_TUNNEL_KEY_ENC_IPV4_SRC, saddr) &&
 227                     !nla_put_in_addr(skb, TCA_TUNNEL_KEY_ENC_IPV4_DST, daddr))
 228                         return 0;
 229         }
 230
 231         if (family == AF_INET6) {
 232                 const struct in6_addr *saddr6 = &info->key.u.ipv6.src;
 233                 const struct in6_addr *daddr6 = &info->key.u.ipv6.dst;
 234
 235                 if (!nla_put_in6_addr(skb,
 236                                       TCA_TUNNEL_KEY_ENC_IPV6_SRC, saddr6) &&
 237                     !nla_put_in6_addr(skb,
 238                                       TCA_TUNNEL_KEY_ENC_IPV6_DST, daddr6))
 239                         return 0;
 240         }
 241
 242         return -EINVAL;
 243 }
 244
 245 static int tunnel_key_dump(struct sk_buff *skb, struct tc_action *a,
 246                            int bind, int ref)
 247 {
 248         unsigned char *b = skb_tail_pointer(skb);
 249         struct tcf_tunnel_key *t = to_tunnel_key(a);
 250         struct tcf_tunnel_key_params *params;
 251         struct tc_tunnel_key opt = {
 252                 .index    = t->tcf_index,
 253                 .refcnt   = t->tcf_refcnt - ref,
 254                 .bindcnt  = t->tcf_bindcnt - bind,
 255         };
 256         struct tcf_t tm;
 257
 258         params = rtnl_dereference(t->params);
 259
 260         opt.t_action = params->tcft_action;
 261         opt.action = params->action;
 262
 263         if (nla_put(skb, TCA_TUNNEL_KEY_PARMS, sizeof(opt), &opt))
 264                 goto nla_put_failure;
 265
 266         if (params->tcft_action == TCA_TUNNEL_KEY_ACT_SET) {
 267                 struct ip_tunnel_key *key =
 268                         &params->tcft_enc_metadata->u.tun_info.key;
 269                 __be32 key_id = tunnel_id_to_key32(key->tun_id);
 270
 271                 if (nla_put_be32(skb, TCA_TUNNEL_KEY_ENC_KEY_ID, key_id) ||
 272                     tunnel_key_dump_addresses(skb,
 273                                               &params->tcft_enc_metadata->u.tun_info) ||
 274                     nla_put_be16(skb, TCA_TUNNEL_KEY_ENC_DST_PORT, key->tp_dst) ||
 275                     nla_put_u8(skb, TCA_TUNNEL_KEY_NO_CSUM,
 276                                !(key->tun_flags & TUNNEL_CSUM)))
 277                         goto nla_put_failure;
 278         }
 279
 280         tcf_tm_dump(&tm, &t->tcf_tm);
 281         if (nla_put_64bit(skb, TCA_TUNNEL_KEY_TM, sizeof(tm),
 282                           &tm, TCA_TUNNEL_KEY_PAD))
 283                 goto nla_put_failure;
 284
 285         return skb->len;
 286
 287 nla_put_failure:
 288         nlmsg_trim(skb, b);
 289         return -1;
 290 }
 291
 292 static int tunnel_key_walker(struct net *net, struct sk_buff *skb,
 293                              struct netlink_callback *cb, int type,
 294                              const struct tc_action_ops *ops)
 295 {
 296         struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
 297
 298         return tcf_generic_walker(tn, skb, cb, type, ops);
 299 }
 300
 301 static int tunnel_key_search(struct net *net, struct tc_action **a, u32 index)
 302 {
 303         struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
 304
 305         return tcf_idr_search(tn, a, index);
 306 }
 307
 308 static struct tc_action_ops act_tunnel_key_ops = {
 309         .kind           =       "tunnel_key",
 310         .type           =       TCA_ACT_TUNNEL_KEY,
 311         .owner          =       THIS_MODULE,
 312         .act            =       tunnel_key_act,
 313         .dump           =       tunnel_key_dump,
 314         .init           =       tunnel_key_init,
 315         .cleanup        =       tunnel_key_release,
 316         .walk           =       tunnel_key_walker,
 317         .lookup         =       tunnel_key_search,
 318         .size           =       sizeof(struct tcf_tunnel_key),
 319 };
 320
 321 static __net_init int tunnel_key_init_net(struct net *net)
 322 {
 323         struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
 324
 325         return tc_action_net_init(tn, &act_tunnel_key_ops);
 326 }
 327
 328 static void __net_exit tunnel_key_exit_net(struct list_head *net_list)
 329 {
 330         tc_action_net_exit(net_list, tunnel_key_net_id);
 331 }
 332
 333 static struct pernet_operations tunnel_key_net_ops = {
 334         .init = tunnel_key_init_net,
 335         .exit_batch = tunnel_key_exit_net,
 336         .id   = &tunnel_key_net_id,
 337         .size = sizeof(struct tc_action_net),
 338 };
 339
 340 static int __init tunnel_key_init_module(void)
 341 {
 342         return tcf_register_action(&act_tunnel_key_ops, &tunnel_key_net_ops);
 343 }
 344
 345 static void __exit tunnel_key_cleanup_module(void)
 346 {
 347         tcf_unregister_action(&act_tunnel_key_ops, &tunnel_key_net_ops);
 348 }
 349
 350 module_init(tunnel_key_init_module);
 351 module_exit(tunnel_key_cleanup_module);
 352
 353 MODULE_AUTHOR("Amir Vadai <amir@vadai.me>");
 354 MODULE_DESCRIPTION("ip tunnel manipulation actions");
 355 MODULE_LICENSE("GPL v2");