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