net/sched/act_skbedit.c

   1 /*
   2  * Copyright (c) 2008, Intel Corporation.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, see <http://www.gnu.org/licenses/>.
  15  *
  16  * Author: Alexander Duyck <alexander.h.duyck@intel.com>
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/init.h>
  21 #include <linux/kernel.h>
  22 #include <linux/skbuff.h>
  23 #include <linux/rtnetlink.h>
  24 #include <net/netlink.h>
  25 #include <net/pkt_sched.h>
  26
  27 #include <linux/tc_act/tc_skbedit.h>
  28 #include <net/tc_act/tc_skbedit.h>
  29
  30 #define SKBEDIT_TAB_MASK     15
  31 static struct tcf_hashinfo skbedit_hash_info;
  32
  33 static int tcf_skbedit(struct sk_buff *skb, const struct tc_action *a,
  34                        struct tcf_result *res)
  35 {
  36         struct tcf_skbedit *d = a->priv;
  37
  38         spin_lock(&d->tcf_lock);
  39         d->tcf_tm.lastuse = jiffies;
  40         bstats_update(&d->tcf_bstats, skb);
  41
  42         if (d->flags & SKBEDIT_F_PRIORITY)
  43                 skb->priority = d->priority;
  44         if (d->flags & SKBEDIT_F_QUEUE_MAPPING &&
  45             skb->dev->real_num_tx_queues > d->queue_mapping)
  46                 skb_set_queue_mapping(skb, d->queue_mapping);
  47         if (d->flags & SKBEDIT_F_MARK)
  48                 skb->mark = d->mark;
  49
  50         spin_unlock(&d->tcf_lock);
  51         return d->tcf_action;
  52 }
  53
  54 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
  55         [TCA_SKBEDIT_PARMS]             = { .len = sizeof(struct tc_skbedit) },
  56         [TCA_SKBEDIT_PRIORITY]          = { .len = sizeof(u32) },
  57         [TCA_SKBEDIT_QUEUE_MAPPING]     = { .len = sizeof(u16) },
  58         [TCA_SKBEDIT_MARK]              = { .len = sizeof(u32) },
  59 };
  60
  61 static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
  62                             struct nlattr *est, struct tc_action *a,
  63                             int ovr, int bind)
  64 {
  65         struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
  66         struct tc_skbedit *parm;
  67         struct tcf_skbedit *d;
  68         struct tcf_common *pc;
  69         u32 flags = 0, *priority = NULL, *mark = NULL;
  70         u16 *queue_mapping = NULL;
  71         int ret = 0, err;
  72
  73         if (nla == NULL)
  74                 return -EINVAL;
  75
  76         err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy);
  77         if (err < 0)
  78                 return err;
  79
  80         if (tb[TCA_SKBEDIT_PARMS] == NULL)
  81                 return -EINVAL;
  82
  83         if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
  84                 flags |= SKBEDIT_F_PRIORITY;
  85                 priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
  86         }
  87
  88         if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
  89                 flags |= SKBEDIT_F_QUEUE_MAPPING;
  90                 queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
  91         }
  92
  93         if (tb[TCA_SKBEDIT_MARK] != NULL) {
  94                 flags |= SKBEDIT_F_MARK;
  95                 mark = nla_data(tb[TCA_SKBEDIT_MARK]);
  96         }
  97
  98         if (!flags)
  99                 return -EINVAL;
 100
 101         parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
 102
 103         pc = tcf_hash_check(parm->index, a, bind);
 104         if (!pc) {
 105                 pc = tcf_hash_create(parm->index, est, a, sizeof(*d), bind);
 106                 if (IS_ERR(pc))
 107                         return PTR_ERR(pc);
 108
 109                 d = to_skbedit(pc);
 110                 ret = ACT_P_CREATED;
 111         } else {
 112                 d = to_skbedit(pc);
 113                 if (bind)
 114                         return 0;
 115                 tcf_hash_release(pc, bind, a->ops->hinfo);
 116                 if (!ovr)
 117                         return -EEXIST;
 118         }
 119
 120         spin_lock_bh(&d->tcf_lock);
 121
 122         d->flags = flags;
 123         if (flags & SKBEDIT_F_PRIORITY)
 124                 d->priority = *priority;
 125         if (flags & SKBEDIT_F_QUEUE_MAPPING)
 126                 d->queue_mapping = *queue_mapping;
 127         if (flags & SKBEDIT_F_MARK)
 128                 d->mark = *mark;
 129
 130         d->tcf_action = parm->action;
 131
 132         spin_unlock_bh(&d->tcf_lock);
 133
 134         if (ret == ACT_P_CREATED)
 135                 tcf_hash_insert(pc, a->ops->hinfo);
 136         return ret;
 137 }
 138
 139 static int tcf_skbedit_cleanup(struct tc_action *a, int bind)
 140 {
 141         struct tcf_skbedit *d = a->priv;
 142
 143         if (d)
 144                 return tcf_hash_release(&d->common, bind, &skbedit_hash_info);
 145         return 0;
 146 }
 147
 148 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
 149                             int bind, int ref)
 150 {
 151         unsigned char *b = skb_tail_pointer(skb);
 152         struct tcf_skbedit *d = a->priv;
 153         struct tc_skbedit opt = {
 154                 .index   = d->tcf_index,
 155                 .refcnt  = d->tcf_refcnt - ref,
 156                 .bindcnt = d->tcf_bindcnt - bind,
 157                 .action  = d->tcf_action,
 158         };
 159         struct tcf_t t;
 160
 161         if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
 162                 goto nla_put_failure;
 163         if ((d->flags & SKBEDIT_F_PRIORITY) &&
 164             nla_put(skb, TCA_SKBEDIT_PRIORITY, sizeof(d->priority),
 165                     &d->priority))
 166                 goto nla_put_failure;
 167         if ((d->flags & SKBEDIT_F_QUEUE_MAPPING) &&
 168             nla_put(skb, TCA_SKBEDIT_QUEUE_MAPPING,
 169                     sizeof(d->queue_mapping), &d->queue_mapping))
 170                 goto nla_put_failure;
 171         if ((d->flags & SKBEDIT_F_MARK) &&
 172             nla_put(skb, TCA_SKBEDIT_MARK, sizeof(d->mark),
 173                     &d->mark))
 174                 goto nla_put_failure;
 175         t.install = jiffies_to_clock_t(jiffies - d->tcf_tm.install);
 176         t.lastuse = jiffies_to_clock_t(jiffies - d->tcf_tm.lastuse);
 177         t.expires = jiffies_to_clock_t(d->tcf_tm.expires);
 178         if (nla_put(skb, TCA_SKBEDIT_TM, sizeof(t), &t))
 179                 goto nla_put_failure;
 180         return skb->len;
 181
 182 nla_put_failure:
 183         nlmsg_trim(skb, b);
 184         return -1;
 185 }
 186
 187 static struct tc_action_ops act_skbedit_ops = {
 188         .kind           =       "skbedit",
 189         .hinfo          =       &skbedit_hash_info,
 190         .type           =       TCA_ACT_SKBEDIT,
 191         .owner          =       THIS_MODULE,
 192         .act            =       tcf_skbedit,
 193         .dump           =       tcf_skbedit_dump,
 194         .cleanup        =       tcf_skbedit_cleanup,
 195         .init           =       tcf_skbedit_init,
 196 };
 197
 198 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
 199 MODULE_DESCRIPTION("SKB Editing");
 200 MODULE_LICENSE("GPL");
 201
 202 static int __init skbedit_init_module(void)
 203 {
 204         int err = tcf_hashinfo_init(&skbedit_hash_info, SKBEDIT_TAB_MASK);
 205         if (err)
 206                 return err;
 207         return tcf_register_action(&act_skbedit_ops);
 208 }
 209
 210 static void __exit skbedit_cleanup_module(void)
 211 {
 212         tcf_hashinfo_destroy(&skbedit_hash_info);
 213         tcf_unregister_action(&act_skbedit_ops);
 214 }
 215
 216 module_init(skbedit_init_module);
 217 module_exit(skbedit_cleanup_module);