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         bstats_cpu_update(this_cpu_ptr(v->common.cpu_bstats), 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         default:
  81                 BUG();
  82         }
  83
  84 out:
  85         if (skb_at_tc_ingress(skb))
  86                 skb_pull_rcsum(skb, skb->mac_len);
  87
  88         return action;
  89
  90 drop:
  91         qstats_drop_inc(this_cpu_ptr(v->common.cpu_qstats));
  92         return TC_ACT_SHOT;
  93 }
  94
  95 static const struct nla_policy vlan_policy[TCA_VLAN_MAX + 1] = {
  96         [TCA_VLAN_PARMS]                = { .len = sizeof(struct tc_vlan) },
  97         [TCA_VLAN_PUSH_VLAN_ID]         = { .type = NLA_U16 },
  98         [TCA_VLAN_PUSH_VLAN_PROTOCOL]   = { .type = NLA_U16 },
  99         [TCA_VLAN_PUSH_VLAN_PRIORITY]   = { .type = NLA_U8 },
 100 };
 101
 102 static int tcf_vlan_init(struct net *net, struct nlattr *nla,
 103                          struct nlattr *est, struct tc_action **a,
 104                          int ovr, int bind, bool rtnl_held,
 105                          struct tcf_proto *tp, struct netlink_ext_ack *extack)
 106 {
 107         struct tc_action_net *tn = net_generic(net, vlan_net_id);
 108         struct nlattr *tb[TCA_VLAN_MAX + 1];
 109         struct tcf_chain *goto_ch = NULL;
 110         struct tcf_vlan_params *p;
 111         struct tc_vlan *parm;
 112         struct tcf_vlan *v;
 113         int action;
 114         u16 push_vid = 0;
 115         __be16 push_proto = 0;
 116         u8 push_prio = 0;
 117         bool exists = false;
 118         int ret = 0, err;
 119         u32 index;
 120
 121         if (!nla)
 122                 return -EINVAL;
 123
 124         err = nla_parse_nested_deprecated(tb, TCA_VLAN_MAX, nla, vlan_policy,
 125                                           NULL);
 126         if (err < 0)
 127                 return err;
 128
 129         if (!tb[TCA_VLAN_PARMS])
 130                 return -EINVAL;
 131         parm = nla_data(tb[TCA_VLAN_PARMS]);
 132         index = parm->index;
 133         err = tcf_idr_check_alloc(tn, &index, a, bind);
 134         if (err < 0)
 135                 return err;
 136         exists = err;
 137         if (exists && bind)
 138                 return 0;
 139
 140         switch (parm->v_action) {
 141         case TCA_VLAN_ACT_POP:
 142                 break;
 143         case TCA_VLAN_ACT_PUSH:
 144         case TCA_VLAN_ACT_MODIFY:
 145                 if (!tb[TCA_VLAN_PUSH_VLAN_ID]) {
 146                         if (exists)
 147                                 tcf_idr_release(*a, bind);
 148                         else
 149                                 tcf_idr_cleanup(tn, index);
 150                         return -EINVAL;
 151                 }
 152                 push_vid = nla_get_u16(tb[TCA_VLAN_PUSH_VLAN_ID]);
 153                 if (push_vid >= VLAN_VID_MASK) {
 154                         if (exists)
 155                                 tcf_idr_release(*a, bind);
 156                         else
 157                                 tcf_idr_cleanup(tn, index);
 158                         return -ERANGE;
 159                 }
 160
 161                 if (tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]) {
 162                         push_proto = nla_get_be16(tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]);
 163                         switch (push_proto) {
 164                         case htons(ETH_P_8021Q):
 165                         case htons(ETH_P_8021AD):
 166                                 break;
 167                         default:
 168                                 if (exists)
 169                                         tcf_idr_release(*a, bind);
 170                                 else
 171                                         tcf_idr_cleanup(tn, index);
 172                                 return -EPROTONOSUPPORT;
 173                         }
 174                 } else {
 175                         push_proto = htons(ETH_P_8021Q);
 176                 }
 177
 178                 if (tb[TCA_VLAN_PUSH_VLAN_PRIORITY])
 179                         push_prio = nla_get_u8(tb[TCA_VLAN_PUSH_VLAN_PRIORITY]);
 180                 break;
 181         default:
 182                 if (exists)
 183                         tcf_idr_release(*a, bind);
 184                 else
 185                         tcf_idr_cleanup(tn, index);
 186                 return -EINVAL;
 187         }
 188         action = parm->v_action;
 189
 190         if (!exists) {
 191                 ret = tcf_idr_create(tn, index, est, a,
 192                                      &act_vlan_ops, bind, true);
 193                 if (ret) {
 194                         tcf_idr_cleanup(tn, index);
 195                         return ret;
 196                 }
 197
 198                 ret = ACT_P_CREATED;
 199         } else if (!ovr) {
 200                 tcf_idr_release(*a, bind);
 201                 return -EEXIST;
 202         }
 203
 204         err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
 205         if (err < 0)
 206                 goto release_idr;
 207
 208         v = to_vlan(*a);
 209
 210         p = kzalloc(sizeof(*p), GFP_KERNEL);
 211         if (!p) {
 212                 err = -ENOMEM;
 213                 goto put_chain;
 214         }
 215
 216         p->tcfv_action = action;
 217         p->tcfv_push_vid = push_vid;
 218         p->tcfv_push_prio = push_prio;
 219         p->tcfv_push_proto = push_proto;
 220
 221         spin_lock_bh(&v->tcf_lock);
 222         goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
 223         rcu_swap_protected(v->vlan_p, p, lockdep_is_held(&v->tcf_lock));
 224         spin_unlock_bh(&v->tcf_lock);
 225
 226         if (goto_ch)
 227                 tcf_chain_put_by_act(goto_ch);
 228         if (p)
 229                 kfree_rcu(p, rcu);
 230
 231         if (ret == ACT_P_CREATED)
 232                 tcf_idr_insert(tn, *a);
 233         return ret;
 234 put_chain:
 235         if (goto_ch)
 236                 tcf_chain_put_by_act(goto_ch);
 237 release_idr:
 238         tcf_idr_release(*a, bind);
 239         return err;
 240 }
 241
 242 static void tcf_vlan_cleanup(struct tc_action *a)
 243 {
 244         struct tcf_vlan *v = to_vlan(a);
 245         struct tcf_vlan_params *p;
 246
 247         p = rcu_dereference_protected(v->vlan_p, 1);
 248         if (p)
 249                 kfree_rcu(p, rcu);
 250 }
 251
 252 static int tcf_vlan_dump(struct sk_buff *skb, struct tc_action *a,
 253                          int bind, int ref)
 254 {
 255         unsigned char *b = skb_tail_pointer(skb);
 256         struct tcf_vlan *v = to_vlan(a);
 257         struct tcf_vlan_params *p;
 258         struct tc_vlan opt = {
 259                 .index    = v->tcf_index,
 260                 .refcnt   = refcount_read(&v->tcf_refcnt) - ref,
 261                 .bindcnt  = atomic_read(&v->tcf_bindcnt) - bind,
 262         };
 263         struct tcf_t t;
 264
 265         spin_lock_bh(&v->tcf_lock);
 266         opt.action = v->tcf_action;
 267         p = rcu_dereference_protected(v->vlan_p, lockdep_is_held(&v->tcf_lock));
 268         opt.v_action = p->tcfv_action;
 269         if (nla_put(skb, TCA_VLAN_PARMS, sizeof(opt), &opt))
 270                 goto nla_put_failure;
 271
 272         if ((p->tcfv_action == TCA_VLAN_ACT_PUSH ||
 273              p->tcfv_action == TCA_VLAN_ACT_MODIFY) &&
 274             (nla_put_u16(skb, TCA_VLAN_PUSH_VLAN_ID, p->tcfv_push_vid) ||
 275              nla_put_be16(skb, TCA_VLAN_PUSH_VLAN_PROTOCOL,
 276                           p->tcfv_push_proto) ||
 277              (nla_put_u8(skb, TCA_VLAN_PUSH_VLAN_PRIORITY,
 278                                               p->tcfv_push_prio))))
 279                 goto nla_put_failure;
 280
 281         tcf_tm_dump(&t, &v->tcf_tm);
 282         if (nla_put_64bit(skb, TCA_VLAN_TM, sizeof(t), &t, TCA_VLAN_PAD))
 283                 goto nla_put_failure;
 284         spin_unlock_bh(&v->tcf_lock);
 285
 286         return skb->len;
 287
 288 nla_put_failure:
 289         spin_unlock_bh(&v->tcf_lock);
 290         nlmsg_trim(skb, b);
 291         return -1;
 292 }
 293
 294 static int tcf_vlan_walker(struct net *net, struct sk_buff *skb,
 295                            struct netlink_callback *cb, int type,
 296                            const struct tc_action_ops *ops,
 297                            struct netlink_ext_ack *extack)
 298 {
 299         struct tc_action_net *tn = net_generic(net, vlan_net_id);
 300
 301         return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 302 }
 303
 304 static void tcf_vlan_stats_update(struct tc_action *a, u64 bytes, u32 packets,
 305                                   u64 lastuse, bool hw)
 306 {
 307         struct tcf_vlan *v = to_vlan(a);
 308         struct tcf_t *tm = &v->tcf_tm;
 309
 310         _bstats_cpu_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
 311         if (hw)
 312                 _bstats_cpu_update(this_cpu_ptr(a->cpu_bstats_hw),
 313                                    bytes, packets);
 314         tm->lastuse = max_t(u64, tm->lastuse, lastuse);
 315 }
 316
 317 static int tcf_vlan_search(struct net *net, struct tc_action **a, u32 index)
 318 {
 319         struct tc_action_net *tn = net_generic(net, vlan_net_id);
 320
 321         return tcf_idr_search(tn, a, index);
 322 }
 323
 324 static size_t tcf_vlan_get_fill_size(const struct tc_action *act)
 325 {
 326         return nla_total_size(sizeof(struct tc_vlan))
 327                 + nla_total_size(sizeof(u16)) /* TCA_VLAN_PUSH_VLAN_ID */
 328                 + nla_total_size(sizeof(u16)) /* TCA_VLAN_PUSH_VLAN_PROTOCOL */
 329                 + nla_total_size(sizeof(u8)); /* TCA_VLAN_PUSH_VLAN_PRIORITY */
 330 }
 331
 332 static struct tc_action_ops act_vlan_ops = {
 333         .kind           =       "vlan",
 334         .id             =       TCA_ID_VLAN,
 335         .owner          =       THIS_MODULE,
 336         .act            =       tcf_vlan_act,
 337         .dump           =       tcf_vlan_dump,
 338         .init           =       tcf_vlan_init,
 339         .cleanup        =       tcf_vlan_cleanup,
 340         .walk           =       tcf_vlan_walker,
 341         .stats_update   =       tcf_vlan_stats_update,
 342         .get_fill_size  =       tcf_vlan_get_fill_size,
 343         .lookup         =       tcf_vlan_search,
 344         .size           =       sizeof(struct tcf_vlan),
 345 };
 346
 347 static __net_init int vlan_init_net(struct net *net)
 348 {
 349         struct tc_action_net *tn = net_generic(net, vlan_net_id);
 350
 351         return tc_action_net_init(net, tn, &act_vlan_ops);
 352 }
 353
 354 static void __net_exit vlan_exit_net(struct list_head *net_list)
 355 {
 356         tc_action_net_exit(net_list, vlan_net_id);
 357 }
 358
 359 static struct pernet_operations vlan_net_ops = {
 360         .init = vlan_init_net,
 361         .exit_batch = vlan_exit_net,
 362         .id   = &vlan_net_id,
 363         .size = sizeof(struct tc_action_net),
 364 };
 365
 366 static int __init vlan_init_module(void)
 367 {
 368         return tcf_register_action(&act_vlan_ops, &vlan_net_ops);
 369 }
 370
 371 static void __exit vlan_cleanup_module(void)
 372 {
 373         tcf_unregister_action(&act_vlan_ops, &vlan_net_ops);
 374 }
 375
 376 module_init(vlan_init_module);
 377 module_exit(vlan_cleanup_module);
 378
 379 MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>");
 380 MODULE_DESCRIPTION("vlan manipulation actions");
 381 MODULE_LICENSE("GPL v2");