net/sched/act_vlan.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (c) 2014 Jiri Pirko <jiri@resnulli.us>
   4  */
   5
   6 #include <linux/module.h>
   7 #include <linux/init.h>
   8 #include <linux/kernel.h>
   9 #include <linux/skbuff.h>
  10 #include <linux/rtnetlink.h>
  11 #include <linux/if_vlan.h>
  12 #include <net/netlink.h>
  13 #include <net/pkt_sched.h>
  14 #include <net/pkt_cls.h>
  15
  16 #include <linux/tc_act/tc_vlan.h>
  17 #include <net/tc_act/tc_vlan.h>
  18
  19 static unsigned int vlan_net_id;
  20 static struct tc_action_ops act_vlan_ops;
  21
  22 static int tcf_vlan_act(struct sk_buff *skb, const struct tc_action *a,
  23                         struct tcf_result *res)
  24 {
  25         struct tcf_vlan *v = to_vlan(a);
  26         struct tcf_vlan_params *p;
  27         int action;
  28         int err;
  29         u16 tci;
  30
  31         tcf_lastuse_update(&v->tcf_tm);
  32         tcf_action_update_bstats(&v->common, skb);
  33
  34         /* Ensure 'data' points at mac_header prior calling vlan manipulating
  35          * functions.
  36          */
  37         if (skb_at_tc_ingress(skb))
  38                 skb_push_rcsum(skb, skb->mac_len);
  39
  40         action = READ_ONCE(v->tcf_action);
  41
  42         p = rcu_dereference_bh(v->vlan_p);
  43
  44         switch (p->tcfv_action) {
  45         case TCA_VLAN_ACT_POP:
  46                 err = skb_vlan_pop(skb);
  47                 if (err)
  48                         goto drop;
  49                 break;
  50         case TCA_VLAN_ACT_PUSH:
  51                 err = skb_vlan_push(skb, p->tcfv_push_proto, p->tcfv_push_vid |
  52                                     (p->tcfv_push_prio << VLAN_PRIO_SHIFT));
  53                 if (err)
  54                         goto drop;
  55                 break;
  56         case TCA_VLAN_ACT_MODIFY:
  57                 /* No-op if no vlan tag (either hw-accel or in-payload) */
  58                 if (!skb_vlan_tagged(skb))
  59                         goto out;
  60                 /* extract existing tag (and guarantee no hw-accel tag) */
  61                 if (skb_vlan_tag_present(skb)) {
  62                         tci = skb_vlan_tag_get(skb);
  63                         __vlan_hwaccel_clear_tag(skb);
  64                 } else {
  65                         /* in-payload vlan tag, pop it */
  66                         err = __skb_vlan_pop(skb, &tci);
  67                         if (err)
  68                                 goto drop;
  69                 }
  70                 /* replace the vid */
  71                 tci = (tci & ~VLAN_VID_MASK) | p->tcfv_push_vid;
  72                 /* replace prio bits, if tcfv_push_prio specified */
  73                 if (p->tcfv_push_prio) {
  74                         tci &= ~VLAN_PRIO_MASK;
  75                         tci |= p->tcfv_push_prio << VLAN_PRIO_SHIFT;
  76                 }
  77                 /* put updated tci as hwaccel tag */
  78                 __vlan_hwaccel_put_tag(skb, p->tcfv_push_proto, tci);
  79                 break;
  80         case TCA_VLAN_ACT_POP_ETH:
  81                 err = skb_eth_pop(skb);
  82                 if (err)
  83                         goto drop;
  84                 break;
  85         case TCA_VLAN_ACT_PUSH_ETH:
  86                 err = skb_eth_push(skb, p->tcfv_push_dst, p->tcfv_push_src);
  87                 if (err)
  88                         goto drop;
  89                 break;
  90         default:
  91                 BUG();
  92         }
  93
  94 out:
  95         if (skb_at_tc_ingress(skb))
  96                 skb_pull_rcsum(skb, skb->mac_len);
  97
  98         return action;
  99
 100 drop:
 101         tcf_action_inc_drop_qstats(&v->common);
 102         return TC_ACT_SHOT;
 103 }
 104
 105 static const struct nla_policy vlan_policy[TCA_VLAN_MAX + 1] = {
 106         [TCA_VLAN_UNSPEC]               = { .strict_start_type = TCA_VLAN_PUSH_ETH_DST },
 107         [TCA_VLAN_PARMS]                = { .len = sizeof(struct tc_vlan) },
 108         [TCA_VLAN_PUSH_VLAN_ID]         = { .type = NLA_U16 },
 109         [TCA_VLAN_PUSH_VLAN_PROTOCOL]   = { .type = NLA_U16 },
 110         [TCA_VLAN_PUSH_VLAN_PRIORITY]   = { .type = NLA_U8 },
 111         [TCA_VLAN_PUSH_ETH_DST]         = NLA_POLICY_ETH_ADDR,
 112         [TCA_VLAN_PUSH_ETH_SRC]         = NLA_POLICY_ETH_ADDR,
 113 };
 114
 115 static int tcf_vlan_init(struct net *net, struct nlattr *nla,
 116                          struct nlattr *est, struct tc_action **a,
 117                          int ovr, int bind, bool rtnl_held,
 118                          struct tcf_proto *tp, u32 flags,
 119                          struct netlink_ext_ack *extack)
 120 {
 121         struct tc_action_net *tn = net_generic(net, vlan_net_id);
 122         struct nlattr *tb[TCA_VLAN_MAX + 1];
 123         struct tcf_chain *goto_ch = NULL;
 124         struct tcf_vlan_params *p;
 125         struct tc_vlan *parm;
 126         struct tcf_vlan *v;
 127         int action;
 128         u16 push_vid = 0;
 129         __be16 push_proto = 0;
 130         u8 push_prio = 0;
 131         bool exists = false;
 132         int ret = 0, err;
 133         u32 index;
 134
 135         if (!nla)
 136                 return -EINVAL;
 137
 138         err = nla_parse_nested_deprecated(tb, TCA_VLAN_MAX, nla, vlan_policy,
 139                                           NULL);
 140         if (err < 0)
 141                 return err;
 142
 143         if (!tb[TCA_VLAN_PARMS])
 144                 return -EINVAL;
 145         parm = nla_data(tb[TCA_VLAN_PARMS]);
 146         index = parm->index;
 147         err = tcf_idr_check_alloc(tn, &index, a, bind);
 148         if (err < 0)
 149                 return err;
 150         exists = err;
 151         if (exists && bind)
 152                 return 0;
 153
 154         switch (parm->v_action) {
 155         case TCA_VLAN_ACT_POP:
 156                 break;
 157         case TCA_VLAN_ACT_PUSH:
 158         case TCA_VLAN_ACT_MODIFY:
 159                 if (!tb[TCA_VLAN_PUSH_VLAN_ID]) {
 160                         if (exists)
 161                                 tcf_idr_release(*a, bind);
 162                         else
 163                                 tcf_idr_cleanup(tn, index);
 164                         return -EINVAL;
 165                 }
 166                 push_vid = nla_get_u16(tb[TCA_VLAN_PUSH_VLAN_ID]);
 167                 if (push_vid >= VLAN_VID_MASK) {
 168                         if (exists)
 169                                 tcf_idr_release(*a, bind);
 170                         else
 171                                 tcf_idr_cleanup(tn, index);
 172                         return -ERANGE;
 173                 }
 174
 175                 if (tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]) {
 176                         push_proto = nla_get_be16(tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]);
 177                         switch (push_proto) {
 178                         case htons(ETH_P_8021Q):
 179                         case htons(ETH_P_8021AD):
 180                                 break;
 181                         default:
 182                                 if (exists)
 183                                         tcf_idr_release(*a, bind);
 184                                 else
 185                                         tcf_idr_cleanup(tn, index);
 186                                 return -EPROTONOSUPPORT;
 187                         }
 188                 } else {
 189                         push_proto = htons(ETH_P_8021Q);
 190                 }
 191
 192                 if (tb[TCA_VLAN_PUSH_VLAN_PRIORITY])
 193                         push_prio = nla_get_u8(tb[TCA_VLAN_PUSH_VLAN_PRIORITY]);
 194                 break;
 195         case TCA_VLAN_ACT_POP_ETH:
 196                 break;
 197         case TCA_VLAN_ACT_PUSH_ETH:
 198                 if (!tb[TCA_VLAN_PUSH_ETH_DST] || !tb[TCA_VLAN_PUSH_ETH_SRC]) {
 199                         if (exists)
 200                                 tcf_idr_release(*a, bind);
 201                         else
 202                                 tcf_idr_cleanup(tn, index);
 203                         return -EINVAL;
 204                 }
 205                 break;
 206         default:
 207                 if (exists)
 208                         tcf_idr_release(*a, bind);
 209                 else
 210                         tcf_idr_cleanup(tn, index);
 211                 return -EINVAL;
 212         }
 213         action = parm->v_action;
 214
 215         if (!exists) {
 216                 ret = tcf_idr_create_from_flags(tn, index, est, a,
 217                                                 &act_vlan_ops, bind, flags);
 218                 if (ret) {
 219                         tcf_idr_cleanup(tn, index);
 220                         return ret;
 221                 }
 222
 223                 ret = ACT_P_CREATED;
 224         } else if (!ovr) {
 225                 tcf_idr_release(*a, bind);
 226                 return -EEXIST;
 227         }
 228
 229         err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
 230         if (err < 0)
 231                 goto release_idr;
 232
 233         v = to_vlan(*a);
 234
 235         p = kzalloc(sizeof(*p), GFP_KERNEL);
 236         if (!p) {
 237                 err = -ENOMEM;
 238                 goto put_chain;
 239         }
 240
 241         p->tcfv_action = action;
 242         p->tcfv_push_vid = push_vid;
 243         p->tcfv_push_prio = push_prio;
 244         p->tcfv_push_proto = push_proto;
 245
 246         if (action == TCA_VLAN_ACT_PUSH_ETH) {
 247                 nla_memcpy(&p->tcfv_push_dst, tb[TCA_VLAN_PUSH_ETH_DST],
 248                            ETH_ALEN);
 249                 nla_memcpy(&p->tcfv_push_src, tb[TCA_VLAN_PUSH_ETH_SRC],
 250                            ETH_ALEN);
 251         }
 252
 253         spin_lock_bh(&v->tcf_lock);
 254         goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
 255         p = rcu_replace_pointer(v->vlan_p, p, lockdep_is_held(&v->tcf_lock));
 256         spin_unlock_bh(&v->tcf_lock);
 257
 258         if (goto_ch)
 259                 tcf_chain_put_by_act(goto_ch);
 260         if (p)
 261                 kfree_rcu(p, rcu);
 262
 263         return ret;
 264 put_chain:
 265         if (goto_ch)
 266                 tcf_chain_put_by_act(goto_ch);
 267 release_idr:
 268         tcf_idr_release(*a, bind);
 269         return err;
 270 }
 271
 272 static void tcf_vlan_cleanup(struct tc_action *a)
 273 {
 274         struct tcf_vlan *v = to_vlan(a);
 275         struct tcf_vlan_params *p;
 276
 277         p = rcu_dereference_protected(v->vlan_p, 1);
 278         if (p)
 279                 kfree_rcu(p, rcu);
 280 }
 281
 282 static int tcf_vlan_dump(struct sk_buff *skb, struct tc_action *a,
 283                          int bind, int ref)
 284 {
 285         unsigned char *b = skb_tail_pointer(skb);
 286         struct tcf_vlan *v = to_vlan(a);
 287         struct tcf_vlan_params *p;
 288         struct tc_vlan opt = {
 289                 .index    = v->tcf_index,
 290                 .refcnt   = refcount_read(&v->tcf_refcnt) - ref,
 291                 .bindcnt  = atomic_read(&v->tcf_bindcnt) - bind,
 292         };
 293         struct tcf_t t;
 294
 295         spin_lock_bh(&v->tcf_lock);
 296         opt.action = v->tcf_action;
 297         p = rcu_dereference_protected(v->vlan_p, lockdep_is_held(&v->tcf_lock));
 298         opt.v_action = p->tcfv_action;
 299         if (nla_put(skb, TCA_VLAN_PARMS, sizeof(opt), &opt))
 300                 goto nla_put_failure;
 301
 302         if ((p->tcfv_action == TCA_VLAN_ACT_PUSH ||
 303              p->tcfv_action == TCA_VLAN_ACT_MODIFY) &&
 304             (nla_put_u16(skb, TCA_VLAN_PUSH_VLAN_ID, p->tcfv_push_vid) ||
 305              nla_put_be16(skb, TCA_VLAN_PUSH_VLAN_PROTOCOL,
 306                           p->tcfv_push_proto) ||
 307              (nla_put_u8(skb, TCA_VLAN_PUSH_VLAN_PRIORITY,
 308                                               p->tcfv_push_prio))))
 309                 goto nla_put_failure;
 310
 311         if (p->tcfv_action == TCA_VLAN_ACT_PUSH_ETH) {
 312                 if (nla_put(skb, TCA_VLAN_PUSH_ETH_DST, ETH_ALEN,
 313                             p->tcfv_push_dst))
 314                         goto nla_put_failure;
 315                 if (nla_put(skb, TCA_VLAN_PUSH_ETH_SRC, ETH_ALEN,
 316                             p->tcfv_push_src))
 317                         goto nla_put_failure;
 318         }
 319
 320         tcf_tm_dump(&t, &v->tcf_tm);
 321         if (nla_put_64bit(skb, TCA_VLAN_TM, sizeof(t), &t, TCA_VLAN_PAD))
 322                 goto nla_put_failure;
 323         spin_unlock_bh(&v->tcf_lock);
 324
 325         return skb->len;
 326
 327 nla_put_failure:
 328         spin_unlock_bh(&v->tcf_lock);
 329         nlmsg_trim(skb, b);
 330         return -1;
 331 }
 332
 333 static int tcf_vlan_walker(struct net *net, struct sk_buff *skb,
 334                            struct netlink_callback *cb, int type,
 335                            const struct tc_action_ops *ops,
 336                            struct netlink_ext_ack *extack)
 337 {
 338         struct tc_action_net *tn = net_generic(net, vlan_net_id);
 339
 340         return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 341 }
 342
 343 static void tcf_vlan_stats_update(struct tc_action *a, u64 bytes, u64 packets,
 344                                   u64 drops, u64 lastuse, bool hw)
 345 {
 346         struct tcf_vlan *v = to_vlan(a);
 347         struct tcf_t *tm = &v->tcf_tm;
 348
 349         tcf_action_update_stats(a, bytes, packets, drops, hw);
 350         tm->lastuse = max_t(u64, tm->lastuse, lastuse);
 351 }
 352
 353 static int tcf_vlan_search(struct net *net, struct tc_action **a, u32 index)
 354 {
 355         struct tc_action_net *tn = net_generic(net, vlan_net_id);
 356
 357         return tcf_idr_search(tn, a, index);
 358 }
 359
 360 static size_t tcf_vlan_get_fill_size(const struct tc_action *act)
 361 {
 362         return nla_total_size(sizeof(struct tc_vlan))
 363                 + nla_total_size(sizeof(u16)) /* TCA_VLAN_PUSH_VLAN_ID */
 364                 + nla_total_size(sizeof(u16)) /* TCA_VLAN_PUSH_VLAN_PROTOCOL */
 365                 + nla_total_size(sizeof(u8)); /* TCA_VLAN_PUSH_VLAN_PRIORITY */
 366 }
 367
 368 static struct tc_action_ops act_vlan_ops = {
 369         .kind           =       "vlan",
 370         .id             =       TCA_ID_VLAN,
 371         .owner          =       THIS_MODULE,
 372         .act            =       tcf_vlan_act,
 373         .dump           =       tcf_vlan_dump,
 374         .init           =       tcf_vlan_init,
 375         .cleanup        =       tcf_vlan_cleanup,
 376         .walk           =       tcf_vlan_walker,
 377         .stats_update   =       tcf_vlan_stats_update,
 378         .get_fill_size  =       tcf_vlan_get_fill_size,
 379         .lookup         =       tcf_vlan_search,
 380         .size           =       sizeof(struct tcf_vlan),
 381 };
 382
 383 static __net_init int vlan_init_net(struct net *net)
 384 {
 385         struct tc_action_net *tn = net_generic(net, vlan_net_id);
 386
 387         return tc_action_net_init(net, tn, &act_vlan_ops);
 388 }
 389
 390 static void __net_exit vlan_exit_net(struct list_head *net_list)
 391 {
 392         tc_action_net_exit(net_list, vlan_net_id);
 393 }
 394
 395 static struct pernet_operations vlan_net_ops = {
 396         .init = vlan_init_net,
 397         .exit_batch = vlan_exit_net,
 398         .id   = &vlan_net_id,
 399         .size = sizeof(struct tc_action_net),
 400 };
 401
 402 static int __init vlan_init_module(void)
 403 {
 404         return tcf_register_action(&act_vlan_ops, &vlan_net_ops);
 405 }
 406
 407 static void __exit vlan_cleanup_module(void)
 408 {
 409         tcf_unregister_action(&act_vlan_ops, &vlan_net_ops);
 410 }
 411
 412 module_init(vlan_init_module);
 413 module_exit(vlan_cleanup_module);
 414
 415 MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>");
 416 MODULE_DESCRIPTION("vlan manipulation actions");
 417 MODULE_LICENSE("GPL v2");