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