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         u32 flags = 0, *priority = NULL, *mark = NULL;
  69         u16 *queue_mapping = NULL;
  70         int ret = 0, err;
  71
  72         if (nla == NULL)
  73                 return -EINVAL;
  74
  75         err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy);
  76         if (err < 0)
  77                 return err;
  78
  79         if (tb[TCA_SKBEDIT_PARMS] == NULL)
  80                 return -EINVAL;
  81
  82         if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
  83                 flags |= SKBEDIT_F_PRIORITY;
  84                 priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
  85         }
  86
  87         if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
  88                 flags |= SKBEDIT_F_QUEUE_MAPPING;
  89                 queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
  90         }
  91
  92         if (tb[TCA_SKBEDIT_MARK] != NULL) {
  93                 flags |= SKBEDIT_F_MARK;
  94                 mark = nla_data(tb[TCA_SKBEDIT_MARK]);
  95         }
  96
  97         if (!flags)
  98                 return -EINVAL;
  99
 100         parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
 101
 102         if (!tcf_hash_check(parm->index, a, bind)) {
 103                 ret = tcf_hash_create(parm->index, est, a, sizeof(*d), bind);
 104                 if (ret)
 105                         return ret;
 106
 107                 d = to_skbedit(a);
 108                 ret = ACT_P_CREATED;
 109         } else {
 110                 d = to_skbedit(a);
 111                 if (bind)
 112                         return 0;
 113                 tcf_hash_release(a, bind);
 114                 if (!ovr)
 115                         return -EEXIST;
 116         }
 117
 118         spin_lock_bh(&d->tcf_lock);
 119
 120         d->flags = flags;
 121         if (flags & SKBEDIT_F_PRIORITY)
 122                 d->priority = *priority;
 123         if (flags & SKBEDIT_F_QUEUE_MAPPING)
 124                 d->queue_mapping = *queue_mapping;
 125         if (flags & SKBEDIT_F_MARK)
 126                 d->mark = *mark;
 127
 128         d->tcf_action = parm->action;
 129
 130         spin_unlock_bh(&d->tcf_lock);
 131
 132         if (ret == ACT_P_CREATED)
 133                 tcf_hash_insert(a);
 134         return ret;
 135 }
 136
 137 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
 138                             int bind, int ref)
 139 {
 140         unsigned char *b = skb_tail_pointer(skb);
 141         struct tcf_skbedit *d = a->priv;
 142         struct tc_skbedit opt = {
 143                 .index   = d->tcf_index,
 144                 .refcnt  = d->tcf_refcnt - ref,
 145                 .bindcnt = d->tcf_bindcnt - bind,
 146                 .action  = d->tcf_action,
 147         };
 148         struct tcf_t t;
 149
 150         if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
 151                 goto nla_put_failure;
 152         if ((d->flags & SKBEDIT_F_PRIORITY) &&
 153             nla_put(skb, TCA_SKBEDIT_PRIORITY, sizeof(d->priority),
 154                     &d->priority))
 155                 goto nla_put_failure;
 156         if ((d->flags & SKBEDIT_F_QUEUE_MAPPING) &&
 157             nla_put(skb, TCA_SKBEDIT_QUEUE_MAPPING,
 158                     sizeof(d->queue_mapping), &d->queue_mapping))
 159                 goto nla_put_failure;
 160         if ((d->flags & SKBEDIT_F_MARK) &&
 161             nla_put(skb, TCA_SKBEDIT_MARK, sizeof(d->mark),
 162                     &d->mark))
 163                 goto nla_put_failure;
 164         t.install = jiffies_to_clock_t(jiffies - d->tcf_tm.install);
 165         t.lastuse = jiffies_to_clock_t(jiffies - d->tcf_tm.lastuse);
 166         t.expires = jiffies_to_clock_t(d->tcf_tm.expires);
 167         if (nla_put(skb, TCA_SKBEDIT_TM, sizeof(t), &t))
 168                 goto nla_put_failure;
 169         return skb->len;
 170
 171 nla_put_failure:
 172         nlmsg_trim(skb, b);
 173         return -1;
 174 }
 175
 176 static struct tc_action_ops act_skbedit_ops = {
 177         .kind           =       "skbedit",
 178         .hinfo          =       &skbedit_hash_info,
 179         .type           =       TCA_ACT_SKBEDIT,
 180         .owner          =       THIS_MODULE,
 181         .act            =       tcf_skbedit,
 182         .dump           =       tcf_skbedit_dump,
 183         .init           =       tcf_skbedit_init,
 184 };
 185
 186 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
 187 MODULE_DESCRIPTION("SKB Editing");
 188 MODULE_LICENSE("GPL");
 189
 190 static int __init skbedit_init_module(void)
 191 {
 192         int err = tcf_hashinfo_init(&skbedit_hash_info, SKBEDIT_TAB_MASK);
 193         if (err)
 194                 return err;
 195         return tcf_register_action(&act_skbedit_ops);
 196 }
 197
 198 static void __exit skbedit_cleanup_module(void)
 199 {
 200         tcf_hashinfo_destroy(&skbedit_hash_info);
 201         tcf_unregister_action(&act_skbedit_ops);
 202 }
 203
 204 module_init(skbedit_init_module);
 205 module_exit(skbedit_cleanup_module);