net/sched/act_vlan.c

   1 /*
   2  * Copyright (c) 2014 Jiri Pirko <jiri@resnulli.us>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/kernel.h>
  13 #include <linux/skbuff.h>
  14 #include <linux/rtnetlink.h>
  15 #include <linux/if_vlan.h>
  16 #include <net/netlink.h>
  17 #include <net/pkt_sched.h>
  18
  19 #include <linux/tc_act/tc_vlan.h>
  20 #include <net/tc_act/tc_vlan.h>
  21
  22 #define VLAN_TAB_MASK     15
  23
  24 static int vlan_net_id;
  25 static struct tc_action_ops act_vlan_ops;
  26
  27 static int tcf_vlan(struct sk_buff *skb, const struct tc_action *a,
  28                     struct tcf_result *res)
  29 {
  30         struct tcf_vlan *v = to_vlan(a);
  31         int action;
  32         int err;
  33         u16 tci;
  34
  35         spin_lock(&v->tcf_lock);
  36         tcf_lastuse_update(&v->tcf_tm);
  37         bstats_update(&v->tcf_bstats, skb);
  38         action = v->tcf_action;
  39
  40         switch (v->tcfv_action) {
  41         case TCA_VLAN_ACT_POP:
  42                 err = skb_vlan_pop(skb);
  43                 if (err)
  44                         goto drop;
  45                 break;
  46         case TCA_VLAN_ACT_PUSH:
  47                 err = skb_vlan_push(skb, v->tcfv_push_proto, v->tcfv_push_vid |
  48                                     (v->tcfv_push_prio << VLAN_PRIO_SHIFT));
  49                 if (err)
  50                         goto drop;
  51                 break;
  52         case TCA_VLAN_ACT_MODIFY:
  53                 /* No-op if no vlan tag (either hw-accel or in-payload) */
  54                 if (!skb_vlan_tagged(skb))
  55                         goto unlock;
  56                 /* extract existing tag (and guarantee no hw-accel tag) */
  57                 if (skb_vlan_tag_present(skb)) {
  58                         tci = skb_vlan_tag_get(skb);
  59                         skb->vlan_tci = 0;
  60                 } else {
  61                         /* in-payload vlan tag, pop it */
  62                         err = __skb_vlan_pop(skb, &tci);
  63                         if (err)
  64                                 goto drop;
  65                 }
  66                 /* replace the vid */
  67                 tci = (tci & ~VLAN_VID_MASK) | v->tcfv_push_vid;
  68                 /* replace prio bits, if tcfv_push_prio specified */
  69                 if (v->tcfv_push_prio) {
  70                         tci &= ~VLAN_PRIO_MASK;
  71                         tci |= v->tcfv_push_prio << VLAN_PRIO_SHIFT;
  72                 }
  73                 /* put updated tci as hwaccel tag */
  74                 __vlan_hwaccel_put_tag(skb, v->tcfv_push_proto, tci);
  75                 break;
  76         default:
  77                 BUG();
  78         }
  79
  80         goto unlock;
  81
  82 drop:
  83         action = TC_ACT_SHOT;
  84         v->tcf_qstats.drops++;
  85 unlock:
  86         spin_unlock(&v->tcf_lock);
  87         return action;
  88 }
  89
  90 static const struct nla_policy vlan_policy[TCA_VLAN_MAX + 1] = {
  91         [TCA_VLAN_PARMS]                = { .len = sizeof(struct tc_vlan) },
  92         [TCA_VLAN_PUSH_VLAN_ID]         = { .type = NLA_U16 },
  93         [TCA_VLAN_PUSH_VLAN_PROTOCOL]   = { .type = NLA_U16 },
  94         [TCA_VLAN_PUSH_VLAN_PRIORITY]   = { .type = NLA_U8 },
  95 };
  96
  97 static int tcf_vlan_init(struct net *net, struct nlattr *nla,
  98                          struct nlattr *est, struct tc_action **a,
  99                          int ovr, int bind)
 100 {
 101         struct tc_action_net *tn = net_generic(net, vlan_net_id);
 102         struct nlattr *tb[TCA_VLAN_MAX + 1];
 103         struct tc_vlan *parm;
 104         struct tcf_vlan *v;
 105         int action;
 106         __be16 push_vid = 0;
 107         __be16 push_proto = 0;
 108         u8 push_prio = 0;
 109         bool exists = false;
 110         int ret = 0, err;
 111
 112         if (!nla)
 113                 return -EINVAL;
 114
 115         err = nla_parse_nested(tb, TCA_VLAN_MAX, nla, vlan_policy);
 116         if (err < 0)
 117                 return err;
 118
 119         if (!tb[TCA_VLAN_PARMS])
 120                 return -EINVAL;
 121         parm = nla_data(tb[TCA_VLAN_PARMS]);
 122         exists = tcf_hash_check(tn, parm->index, a, bind);
 123         if (exists && bind)
 124                 return 0;
 125
 126         switch (parm->v_action) {
 127         case TCA_VLAN_ACT_POP:
 128                 break;
 129         case TCA_VLAN_ACT_PUSH:
 130         case TCA_VLAN_ACT_MODIFY:
 131                 if (!tb[TCA_VLAN_PUSH_VLAN_ID]) {
 132                         if (exists)
 133                                 tcf_hash_release(*a, bind);
 134                         return -EINVAL;
 135                 }
 136                 push_vid = nla_get_u16(tb[TCA_VLAN_PUSH_VLAN_ID]);
 137                 if (push_vid >= VLAN_VID_MASK) {
 138                         if (exists)
 139                                 tcf_hash_release(*a, bind);
 140                         return -ERANGE;
 141                 }
 142
 143                 if (tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]) {
 144                         push_proto = nla_get_be16(tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]);
 145                         switch (push_proto) {
 146                         case htons(ETH_P_8021Q):
 147                         case htons(ETH_P_8021AD):
 148                                 break;
 149                         default:
 150                                 return -EPROTONOSUPPORT;
 151                         }
 152                 } else {
 153                         push_proto = htons(ETH_P_8021Q);
 154                 }
 155
 156                 if (tb[TCA_VLAN_PUSH_VLAN_PRIORITY])
 157                         push_prio = nla_get_u8(tb[TCA_VLAN_PUSH_VLAN_PRIORITY]);
 158                 break;
 159         default:
 160                 if (exists)
 161                         tcf_hash_release(*a, bind);
 162                 return -EINVAL;
 163         }
 164         action = parm->v_action;
 165
 166         if (!exists) {
 167                 ret = tcf_hash_create(tn, parm->index, est, a,
 168                                       &act_vlan_ops, bind, false);
 169                 if (ret)
 170                         return ret;
 171
 172                 ret = ACT_P_CREATED;
 173         } else {
 174                 tcf_hash_release(*a, bind);
 175                 if (!ovr)
 176                         return -EEXIST;
 177         }
 178
 179         v = to_vlan(*a);
 180
 181         spin_lock_bh(&v->tcf_lock);
 182
 183         v->tcfv_action = action;
 184         v->tcfv_push_vid = push_vid;
 185         v->tcfv_push_prio = push_prio;
 186         v->tcfv_push_proto = push_proto;
 187
 188         v->tcf_action = parm->action;
 189
 190         spin_unlock_bh(&v->tcf_lock);
 191
 192         if (ret == ACT_P_CREATED)
 193                 tcf_hash_insert(tn, *a);
 194         return ret;
 195 }
 196
 197 static int tcf_vlan_dump(struct sk_buff *skb, struct tc_action *a,
 198                          int bind, int ref)
 199 {
 200         unsigned char *b = skb_tail_pointer(skb);
 201         struct tcf_vlan *v = to_vlan(a);
 202         struct tc_vlan opt = {
 203                 .index    = v->tcf_index,
 204                 .refcnt   = v->tcf_refcnt - ref,
 205                 .bindcnt  = v->tcf_bindcnt - bind,
 206                 .action   = v->tcf_action,
 207                 .v_action = v->tcfv_action,
 208         };
 209         struct tcf_t t;
 210
 211         if (nla_put(skb, TCA_VLAN_PARMS, sizeof(opt), &opt))
 212                 goto nla_put_failure;
 213
 214         if ((v->tcfv_action == TCA_VLAN_ACT_PUSH ||
 215              v->tcfv_action == TCA_VLAN_ACT_MODIFY) &&
 216             (nla_put_u16(skb, TCA_VLAN_PUSH_VLAN_ID, v->tcfv_push_vid) ||
 217              nla_put_be16(skb, TCA_VLAN_PUSH_VLAN_PROTOCOL,
 218                           v->tcfv_push_proto) ||
 219              (nla_put_u8(skb, TCA_VLAN_PUSH_VLAN_PRIORITY,
 220                                               v->tcfv_push_prio))))
 221                 goto nla_put_failure;
 222
 223         tcf_tm_dump(&t, &v->tcf_tm);
 224         if (nla_put_64bit(skb, TCA_VLAN_TM, sizeof(t), &t, TCA_VLAN_PAD))
 225                 goto nla_put_failure;
 226         return skb->len;
 227
 228 nla_put_failure:
 229         nlmsg_trim(skb, b);
 230         return -1;
 231 }
 232
 233 static int tcf_vlan_walker(struct net *net, struct sk_buff *skb,
 234                            struct netlink_callback *cb, int type,
 235                            const struct tc_action_ops *ops)
 236 {
 237         struct tc_action_net *tn = net_generic(net, vlan_net_id);
 238
 239         return tcf_generic_walker(tn, skb, cb, type, ops);
 240 }
 241
 242 static int tcf_vlan_search(struct net *net, struct tc_action **a, u32 index)
 243 {
 244         struct tc_action_net *tn = net_generic(net, vlan_net_id);
 245
 246         return tcf_hash_search(tn, a, index);
 247 }
 248
 249 static struct tc_action_ops act_vlan_ops = {
 250         .kind           =       "vlan",
 251         .type           =       TCA_ACT_VLAN,
 252         .owner          =       THIS_MODULE,
 253         .act            =       tcf_vlan,
 254         .dump           =       tcf_vlan_dump,
 255         .init           =       tcf_vlan_init,
 256         .walk           =       tcf_vlan_walker,
 257         .lookup         =       tcf_vlan_search,
 258         .size           =       sizeof(struct tcf_vlan),
 259 };
 260
 261 static __net_init int vlan_init_net(struct net *net)
 262 {
 263         struct tc_action_net *tn = net_generic(net, vlan_net_id);
 264
 265         return tc_action_net_init(tn, &act_vlan_ops, VLAN_TAB_MASK);
 266 }
 267
 268 static void __net_exit vlan_exit_net(struct net *net)
 269 {
 270         struct tc_action_net *tn = net_generic(net, vlan_net_id);
 271
 272         tc_action_net_exit(tn);
 273 }
 274
 275 static struct pernet_operations vlan_net_ops = {
 276         .init = vlan_init_net,
 277         .exit = vlan_exit_net,
 278         .id   = &vlan_net_id,
 279         .size = sizeof(struct tc_action_net),
 280 };
 281
 282 static int __init vlan_init_module(void)
 283 {
 284         return tcf_register_action(&act_vlan_ops, &vlan_net_ops);
 285 }
 286
 287 static void __exit vlan_cleanup_module(void)
 288 {
 289         tcf_unregister_action(&act_vlan_ops, &vlan_net_ops);
 290 }
 291
 292 module_init(vlan_init_module);
 293 module_exit(vlan_cleanup_module);
 294
 295 MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>");
 296 MODULE_DESCRIPTION("vlan manipulation actions");
 297 MODULE_LICENSE("GPL v2");