kernel/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 tcf_vlan(struct sk_buff *skb, const struct tc_action *a,
  25                     struct tcf_result *res)
  26 {
  27         struct tcf_vlan *v = a->priv;
  28         int action;
  29         int err;
  30
  31         spin_lock(&v->tcf_lock);
  32         v->tcf_tm.lastuse = jiffies;
  33         bstats_update(&v->tcf_bstats, skb);
  34         action = v->tcf_action;
  35
  36         switch (v->tcfv_action) {
  37         case TCA_VLAN_ACT_POP:
  38                 err = skb_vlan_pop(skb);
  39                 if (err)
  40                         goto drop;
  41                 break;
  42         case TCA_VLAN_ACT_PUSH:
  43                 err = skb_vlan_push(skb, v->tcfv_push_proto, v->tcfv_push_vid);
  44                 if (err)
  45                         goto drop;
  46                 break;
  47         default:
  48                 BUG();
  49         }
  50
  51         goto unlock;
  52
  53 drop:
  54         action = TC_ACT_SHOT;
  55         v->tcf_qstats.drops++;
  56 unlock:
  57         spin_unlock(&v->tcf_lock);
  58         return action;
  59 }
  60
  61 static const struct nla_policy vlan_policy[TCA_VLAN_MAX + 1] = {
  62         [TCA_VLAN_PARMS]                = { .len = sizeof(struct tc_vlan) },
  63         [TCA_VLAN_PUSH_VLAN_ID]         = { .type = NLA_U16 },
  64         [TCA_VLAN_PUSH_VLAN_PROTOCOL]   = { .type = NLA_U16 },
  65 };
  66
  67 static int tcf_vlan_init(struct net *net, struct nlattr *nla,
  68                          struct nlattr *est, struct tc_action *a,
  69                          int ovr, int bind)
  70 {
  71         struct nlattr *tb[TCA_VLAN_MAX + 1];
  72         struct tc_vlan *parm;
  73         struct tcf_vlan *v;
  74         int action;
  75         __be16 push_vid = 0;
  76         __be16 push_proto = 0;
  77         int ret = 0;
  78         int err;
  79
  80         if (!nla)
  81                 return -EINVAL;
  82
  83         err = nla_parse_nested(tb, TCA_VLAN_MAX, nla, vlan_policy);
  84         if (err < 0)
  85                 return err;
  86
  87         if (!tb[TCA_VLAN_PARMS])
  88                 return -EINVAL;
  89         parm = nla_data(tb[TCA_VLAN_PARMS]);
  90         switch (parm->v_action) {
  91         case TCA_VLAN_ACT_POP:
  92                 break;
  93         case TCA_VLAN_ACT_PUSH:
  94                 if (!tb[TCA_VLAN_PUSH_VLAN_ID])
  95                         return -EINVAL;
  96                 push_vid = nla_get_u16(tb[TCA_VLAN_PUSH_VLAN_ID]);
  97                 if (push_vid >= VLAN_VID_MASK)
  98                         return -ERANGE;
  99
 100                 if (tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]) {
 101                         push_proto = nla_get_be16(tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]);
 102                         switch (push_proto) {
 103                         case htons(ETH_P_8021Q):
 104                         case htons(ETH_P_8021AD):
 105                                 break;
 106                         default:
 107                                 return -EPROTONOSUPPORT;
 108                         }
 109                 } else {
 110                         push_proto = htons(ETH_P_8021Q);
 111                 }
 112                 break;
 113         default:
 114                 return -EINVAL;
 115         }
 116         action = parm->v_action;
 117
 118         if (!tcf_hash_check(parm->index, a, bind)) {
 119                 ret = tcf_hash_create(parm->index, est, a, sizeof(*v), bind);
 120                 if (ret)
 121                         return ret;
 122
 123                 ret = ACT_P_CREATED;
 124         } else {
 125                 if (bind)
 126                         return 0;
 127                 tcf_hash_release(a, bind);
 128                 if (!ovr)
 129                         return -EEXIST;
 130         }
 131
 132         v = to_vlan(a);
 133
 134         spin_lock_bh(&v->tcf_lock);
 135
 136         v->tcfv_action = action;
 137         v->tcfv_push_vid = push_vid;
 138         v->tcfv_push_proto = push_proto;
 139
 140         v->tcf_action = parm->action;
 141
 142         spin_unlock_bh(&v->tcf_lock);
 143
 144         if (ret == ACT_P_CREATED)
 145                 tcf_hash_insert(a);
 146         return ret;
 147 }
 148
 149 static int tcf_vlan_dump(struct sk_buff *skb, struct tc_action *a,
 150                          int bind, int ref)
 151 {
 152         unsigned char *b = skb_tail_pointer(skb);
 153         struct tcf_vlan *v = a->priv;
 154         struct tc_vlan opt = {
 155                 .index    = v->tcf_index,
 156                 .refcnt   = v->tcf_refcnt - ref,
 157                 .bindcnt  = v->tcf_bindcnt - bind,
 158                 .action   = v->tcf_action,
 159                 .v_action = v->tcfv_action,
 160         };
 161         struct tcf_t t;
 162
 163         if (nla_put(skb, TCA_VLAN_PARMS, sizeof(opt), &opt))
 164                 goto nla_put_failure;
 165
 166         if (v->tcfv_action == TCA_VLAN_ACT_PUSH &&
 167             (nla_put_u16(skb, TCA_VLAN_PUSH_VLAN_ID, v->tcfv_push_vid) ||
 168              nla_put_be16(skb, TCA_VLAN_PUSH_VLAN_PROTOCOL, v->tcfv_push_proto)))
 169                 goto nla_put_failure;
 170
 171         t.install = jiffies_to_clock_t(jiffies - v->tcf_tm.install);
 172         t.lastuse = jiffies_to_clock_t(jiffies - v->tcf_tm.lastuse);
 173         t.expires = jiffies_to_clock_t(v->tcf_tm.expires);
 174         if (nla_put(skb, TCA_VLAN_TM, sizeof(t), &t))
 175                 goto nla_put_failure;
 176         return skb->len;
 177
 178 nla_put_failure:
 179         nlmsg_trim(skb, b);
 180         return -1;
 181 }
 182
 183 static struct tc_action_ops act_vlan_ops = {
 184         .kind           =       "vlan",
 185         .type           =       TCA_ACT_VLAN,
 186         .owner          =       THIS_MODULE,
 187         .act            =       tcf_vlan,
 188         .dump           =       tcf_vlan_dump,
 189         .init           =       tcf_vlan_init,
 190 };
 191
 192 static int __init vlan_init_module(void)
 193 {
 194         return tcf_register_action(&act_vlan_ops, VLAN_TAB_MASK);
 195 }
 196
 197 static void __exit vlan_cleanup_module(void)
 198 {
 199         tcf_unregister_action(&act_vlan_ops);
 200 }
 201
 202 module_init(vlan_init_module);
 203 module_exit(vlan_cleanup_module);
 204
 205 MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>");
 206 MODULE_DESCRIPTION("vlan manipulation actions");
 207 MODULE_LICENSE("GPL v2");