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
  26 static int tcf_vlan(struct sk_buff *skb, const struct tc_action *a,
  27                     struct tcf_result *res)
  28 {
  29         struct tcf_vlan *v = a->priv;
  30         int action;
  31         int err;
  32
  33         spin_lock(&v->tcf_lock);
  34         v->tcf_tm.lastuse = jiffies;
  35         bstats_update(&v->tcf_bstats, skb);
  36         action = v->tcf_action;
  37
  38         switch (v->tcfv_action) {
  39         case TCA_VLAN_ACT_POP:
  40                 err = skb_vlan_pop(skb);
  41                 if (err)
  42                         goto drop;
  43                 break;
  44         case TCA_VLAN_ACT_PUSH:
  45                 err = skb_vlan_push(skb, v->tcfv_push_proto, v->tcfv_push_vid);
  46                 if (err)
  47                         goto drop;
  48                 break;
  49         default:
  50                 BUG();
  51         }
  52
  53         goto unlock;
  54
  55 drop:
  56         action = TC_ACT_SHOT;
  57         v->tcf_qstats.drops++;
  58 unlock:
  59         spin_unlock(&v->tcf_lock);
  60         return action;
  61 }
  62
  63 static const struct nla_policy vlan_policy[TCA_VLAN_MAX + 1] = {
  64         [TCA_VLAN_PARMS]                = { .len = sizeof(struct tc_vlan) },
  65         [TCA_VLAN_PUSH_VLAN_ID]         = { .type = NLA_U16 },
  66         [TCA_VLAN_PUSH_VLAN_PROTOCOL]   = { .type = NLA_U16 },
  67 };
  68
  69 static int tcf_vlan_init(struct net *net, struct nlattr *nla,
  70                          struct nlattr *est, struct tc_action *a,
  71                          int ovr, int bind)
  72 {
  73         struct tc_action_net *tn = net_generic(net, vlan_net_id);
  74         struct nlattr *tb[TCA_VLAN_MAX + 1];
  75         struct tc_vlan *parm;
  76         struct tcf_vlan *v;
  77         int action;
  78         __be16 push_vid = 0;
  79         __be16 push_proto = 0;
  80         int ret = 0, exists = 0;
  81         int err;
  82
  83         if (!nla)
  84                 return -EINVAL;
  85
  86         err = nla_parse_nested(tb, TCA_VLAN_MAX, nla, vlan_policy);
  87         if (err < 0)
  88                 return err;
  89
  90         if (!tb[TCA_VLAN_PARMS])
  91                 return -EINVAL;
  92         parm = nla_data(tb[TCA_VLAN_PARMS]);
  93         exists = tcf_hash_check(tn, parm->index, a, bind);
  94         if (exists && bind)
  95                 return 0;
  96
  97         switch (parm->v_action) {
  98         case TCA_VLAN_ACT_POP:
  99                 break;
 100         case TCA_VLAN_ACT_PUSH:
 101                 if (!tb[TCA_VLAN_PUSH_VLAN_ID]) {
 102                         if (exists)
 103                                 tcf_hash_release(a, bind);
 104                         return -EINVAL;
 105                 }
 106                 push_vid = nla_get_u16(tb[TCA_VLAN_PUSH_VLAN_ID]);
 107                 if (push_vid >= VLAN_VID_MASK) {
 108                         if (exists)
 109                                 tcf_hash_release(a, bind);
 110                         return -ERANGE;
 111                 }
 112
 113                 if (tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]) {
 114                         push_proto = nla_get_be16(tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]);
 115                         switch (push_proto) {
 116                         case htons(ETH_P_8021Q):
 117                         case htons(ETH_P_8021AD):
 118                                 break;
 119                         default:
 120                                 return -EPROTONOSUPPORT;
 121                         }
 122                 } else {
 123                         push_proto = htons(ETH_P_8021Q);
 124                 }
 125                 break;
 126         default:
 127                 if (exists)
 128                         tcf_hash_release(a, bind);
 129                 return -EINVAL;
 130         }
 131         action = parm->v_action;
 132
 133         if (!exists) {
 134                 ret = tcf_hash_create(tn, parm->index, est, a,
 135                                       sizeof(*v), bind, false);
 136                 if (ret)
 137                         return ret;
 138
 139                 ret = ACT_P_CREATED;
 140         } else {
 141                 tcf_hash_release(a, bind);
 142                 if (!ovr)
 143                         return -EEXIST;
 144         }
 145
 146         v = to_vlan(a);
 147
 148         spin_lock_bh(&v->tcf_lock);
 149
 150         v->tcfv_action = action;
 151         v->tcfv_push_vid = push_vid;
 152         v->tcfv_push_proto = push_proto;
 153
 154         v->tcf_action = parm->action;
 155
 156         spin_unlock_bh(&v->tcf_lock);
 157
 158         if (ret == ACT_P_CREATED)
 159                 tcf_hash_insert(tn, a);
 160         return ret;
 161 }
 162
 163 static int tcf_vlan_dump(struct sk_buff *skb, struct tc_action *a,
 164                          int bind, int ref)
 165 {
 166         unsigned char *b = skb_tail_pointer(skb);
 167         struct tcf_vlan *v = a->priv;
 168         struct tc_vlan opt = {
 169                 .index    = v->tcf_index,
 170                 .refcnt   = v->tcf_refcnt - ref,
 171                 .bindcnt  = v->tcf_bindcnt - bind,
 172                 .action   = v->tcf_action,
 173                 .v_action = v->tcfv_action,
 174         };
 175         struct tcf_t t;
 176
 177         if (nla_put(skb, TCA_VLAN_PARMS, sizeof(opt), &opt))
 178                 goto nla_put_failure;
 179
 180         if (v->tcfv_action == TCA_VLAN_ACT_PUSH &&
 181             (nla_put_u16(skb, TCA_VLAN_PUSH_VLAN_ID, v->tcfv_push_vid) ||
 182              nla_put_be16(skb, TCA_VLAN_PUSH_VLAN_PROTOCOL, v->tcfv_push_proto)))
 183                 goto nla_put_failure;
 184
 185         t.install = jiffies_to_clock_t(jiffies - v->tcf_tm.install);
 186         t.lastuse = jiffies_to_clock_t(jiffies - v->tcf_tm.lastuse);
 187         t.expires = jiffies_to_clock_t(v->tcf_tm.expires);
 188         if (nla_put(skb, TCA_VLAN_TM, sizeof(t), &t))
 189                 goto nla_put_failure;
 190         return skb->len;
 191
 192 nla_put_failure:
 193         nlmsg_trim(skb, b);
 194         return -1;
 195 }
 196
 197 static int tcf_vlan_walker(struct net *net, struct sk_buff *skb,
 198                            struct netlink_callback *cb, int type,
 199                            struct tc_action *a)
 200 {
 201         struct tc_action_net *tn = net_generic(net, vlan_net_id);
 202
 203         return tcf_generic_walker(tn, skb, cb, type, a);
 204 }
 205
 206 static int tcf_vlan_search(struct net *net, struct tc_action *a, u32 index)
 207 {
 208         struct tc_action_net *tn = net_generic(net, vlan_net_id);
 209
 210         return tcf_hash_search(tn, a, index);
 211 }
 212
 213 static struct tc_action_ops act_vlan_ops = {
 214         .kind           =       "vlan",
 215         .type           =       TCA_ACT_VLAN,
 216         .owner          =       THIS_MODULE,
 217         .act            =       tcf_vlan,
 218         .dump           =       tcf_vlan_dump,
 219         .init           =       tcf_vlan_init,
 220         .walk           =       tcf_vlan_walker,
 221         .lookup         =       tcf_vlan_search,
 222 };
 223
 224 static __net_init int vlan_init_net(struct net *net)
 225 {
 226         struct tc_action_net *tn = net_generic(net, vlan_net_id);
 227
 228         return tc_action_net_init(tn, &act_vlan_ops, VLAN_TAB_MASK);
 229 }
 230
 231 static void __net_exit vlan_exit_net(struct net *net)
 232 {
 233         struct tc_action_net *tn = net_generic(net, vlan_net_id);
 234
 235         tc_action_net_exit(tn);
 236 }
 237
 238 static struct pernet_operations vlan_net_ops = {
 239         .init = vlan_init_net,
 240         .exit = vlan_exit_net,
 241         .id   = &vlan_net_id,
 242         .size = sizeof(struct tc_action_net),
 243 };
 244
 245 static int __init vlan_init_module(void)
 246 {
 247         return tcf_register_action(&act_vlan_ops, &vlan_net_ops);
 248 }
 249
 250 static void __exit vlan_cleanup_module(void)
 251 {
 252         tcf_unregister_action(&act_vlan_ops, &vlan_net_ops);
 253 }
 254
 255 module_init(vlan_init_module);
 256 module_exit(vlan_cleanup_module);
 257
 258 MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>");
 259 MODULE_DESCRIPTION("vlan manipulation actions");
 260 MODULE_LICENSE("GPL v2");