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 u32 skbedit_idx_gen;
  32 static struct tcf_hashinfo skbedit_hash_info;
  33
  34 static int tcf_skbedit(struct sk_buff *skb, const struct tc_action *a,
  35                        struct tcf_result *res)
  36 {
  37         struct tcf_skbedit *d = a->priv;
  38
  39         spin_lock(&d->tcf_lock);
  40         d->tcf_tm.lastuse = jiffies;
  41         bstats_update(&d->tcf_bstats, skb);
  42
  43         if (d->flags & SKBEDIT_F_PRIORITY)
  44                 skb->priority = d->priority;
  45         if (d->flags & SKBEDIT_F_QUEUE_MAPPING &&
  46             skb->dev->real_num_tx_queues > d->queue_mapping)
  47                 skb_set_queue_mapping(skb, d->queue_mapping);
  48         if (d->flags & SKBEDIT_F_MARK)
  49                 skb->mark = d->mark;
  50
  51         spin_unlock(&d->tcf_lock);
  52         return d->tcf_action;
  53 }
  54
  55 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
  56         [TCA_SKBEDIT_PARMS]             = { .len = sizeof(struct tc_skbedit) },
  57         [TCA_SKBEDIT_PRIORITY]          = { .len = sizeof(u32) },
  58         [TCA_SKBEDIT_QUEUE_MAPPING]     = { .len = sizeof(u16) },
  59         [TCA_SKBEDIT_MARK]              = { .len = sizeof(u32) },
  60 };
  61
  62 static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
  63                             struct nlattr *est, struct tc_action *a,
  64                             int ovr, int bind)
  65 {
  66         struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
  67         struct tc_skbedit *parm;
  68         struct tcf_skbedit *d;
  69         struct tcf_common *pc;
  70         u32 flags = 0, *priority = NULL, *mark = NULL;
  71         u16 *queue_mapping = NULL;
  72         int ret = 0, err;
  73
  74         if (nla == NULL)
  75                 return -EINVAL;
  76
  77         err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy);
  78         if (err < 0)
  79                 return err;
  80
  81         if (tb[TCA_SKBEDIT_PARMS] == NULL)
  82                 return -EINVAL;
  83
  84         if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
  85                 flags |= SKBEDIT_F_PRIORITY;
  86                 priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
  87         }
  88
  89         if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
  90                 flags |= SKBEDIT_F_QUEUE_MAPPING;
  91                 queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
  92         }
  93
  94         if (tb[TCA_SKBEDIT_MARK] != NULL) {
  95                 flags |= SKBEDIT_F_MARK;
  96                 mark = nla_data(tb[TCA_SKBEDIT_MARK]);
  97         }
  98
  99         if (!flags)
 100                 return -EINVAL;
 101
 102         parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
 103
 104         pc = tcf_hash_check(parm->index, a, bind, &skbedit_hash_info);
 105         if (!pc) {
 106                 pc = tcf_hash_create(parm->index, est, a, sizeof(*d), bind,
 107                                      &skbedit_idx_gen, &skbedit_hash_info);
 108                 if (IS_ERR(pc))
 109                         return PTR_ERR(pc);
 110
 111                 d = to_skbedit(pc);
 112                 ret = ACT_P_CREATED;
 113         } else {
 114                 d = to_skbedit(pc);
 115                 if (bind)
 116                         return 0;
 117                 tcf_hash_release(pc, bind, &skbedit_hash_info);
 118                 if (!ovr)
 119                         return -EEXIST;
 120         }
 121
 122         spin_lock_bh(&d->tcf_lock);
 123
 124         d->flags = flags;
 125         if (flags & SKBEDIT_F_PRIORITY)
 126                 d->priority = *priority;
 127         if (flags & SKBEDIT_F_QUEUE_MAPPING)
 128                 d->queue_mapping = *queue_mapping;
 129         if (flags & SKBEDIT_F_MARK)
 130                 d->mark = *mark;
 131
 132         d->tcf_action = parm->action;
 133
 134         spin_unlock_bh(&d->tcf_lock);
 135
 136         if (ret == ACT_P_CREATED)
 137                 tcf_hash_insert(pc, &skbedit_hash_info);
 138         return ret;
 139 }
 140
 141 static int tcf_skbedit_cleanup(struct tc_action *a, int bind)
 142 {
 143         struct tcf_skbedit *d = a->priv;
 144
 145         if (d)
 146                 return tcf_hash_release(&d->common, bind, &skbedit_hash_info);
 147         return 0;
 148 }
 149
 150 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
 151                             int bind, int ref)
 152 {
 153         unsigned char *b = skb_tail_pointer(skb);
 154         struct tcf_skbedit *d = a->priv;
 155         struct tc_skbedit opt = {
 156                 .index   = d->tcf_index,
 157                 .refcnt  = d->tcf_refcnt - ref,
 158                 .bindcnt = d->tcf_bindcnt - bind,
 159                 .action  = d->tcf_action,
 160         };
 161         struct tcf_t t;
 162
 163         if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
 164                 goto nla_put_failure;
 165         if ((d->flags & SKBEDIT_F_PRIORITY) &&
 166             nla_put(skb, TCA_SKBEDIT_PRIORITY, sizeof(d->priority),
 167                     &d->priority))
 168                 goto nla_put_failure;
 169         if ((d->flags & SKBEDIT_F_QUEUE_MAPPING) &&
 170             nla_put(skb, TCA_SKBEDIT_QUEUE_MAPPING,
 171                     sizeof(d->queue_mapping), &d->queue_mapping))
 172                 goto nla_put_failure;
 173         if ((d->flags & SKBEDIT_F_MARK) &&
 174             nla_put(skb, TCA_SKBEDIT_MARK, sizeof(d->mark),
 175                     &d->mark))
 176                 goto nla_put_failure;
 177         t.install = jiffies_to_clock_t(jiffies - d->tcf_tm.install);
 178         t.lastuse = jiffies_to_clock_t(jiffies - d->tcf_tm.lastuse);
 179         t.expires = jiffies_to_clock_t(d->tcf_tm.expires);
 180         if (nla_put(skb, TCA_SKBEDIT_TM, sizeof(t), &t))
 181                 goto nla_put_failure;
 182         return skb->len;
 183
 184 nla_put_failure:
 185         nlmsg_trim(skb, b);
 186         return -1;
 187 }
 188
 189 static struct tc_action_ops act_skbedit_ops = {
 190         .kind           =       "skbedit",
 191         .hinfo          =       &skbedit_hash_info,
 192         .type           =       TCA_ACT_SKBEDIT,
 193         .capab          =       TCA_CAP_NONE,
 194         .owner          =       THIS_MODULE,
 195         .act            =       tcf_skbedit,
 196         .dump           =       tcf_skbedit_dump,
 197         .cleanup        =       tcf_skbedit_cleanup,
 198         .init           =       tcf_skbedit_init,
 199 };
 200
 201 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
 202 MODULE_DESCRIPTION("SKB Editing");
 203 MODULE_LICENSE("GPL");
 204
 205 static int __init skbedit_init_module(void)
 206 {
 207         int err = tcf_hashinfo_init(&skbedit_hash_info, SKBEDIT_TAB_MASK);
 208         if (err)
 209                 return err;
 210         return tcf_register_action(&act_skbedit_ops);
 211 }
 212
 213 static void __exit skbedit_cleanup_module(void)
 214 {
 215         tcf_hashinfo_destroy(&skbedit_hash_info);
 216         tcf_unregister_action(&act_skbedit_ops);
 217 }
 218
 219 module_init(skbedit_init_module);
 220 module_exit(skbedit_cleanup_module);