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
  32 static int skbedit_net_id;
  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 tc_action_net *tn = net_generic(net, skbedit_net_id);
  67         struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
  68         struct tc_skbedit *parm;
  69         struct tcf_skbedit *d;
  70         u32 flags = 0, *priority = NULL, *mark = NULL;
  71         u16 *queue_mapping = NULL;
  72         int ret = 0, err, exists = 0;
  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         parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
 100
 101         exists = tcf_hash_check(tn, parm->index, a, bind);
 102         if (exists && bind)
 103                 return 0;
 104
 105         if (!flags) {
 106                 tcf_hash_release(a, bind);
 107                 return -EINVAL;
 108         }
 109
 110         if (!exists) {
 111                 ret = tcf_hash_create(tn, parm->index, est, a,
 112                                       sizeof(*d), bind, false);
 113                 if (ret)
 114                         return ret;
 115
 116                 d = to_skbedit(a);
 117                 ret = ACT_P_CREATED;
 118         } else {
 119                 d = to_skbedit(a);
 120                 tcf_hash_release(a, bind);
 121                 if (!ovr)
 122                         return -EEXIST;
 123         }
 124
 125         spin_lock_bh(&d->tcf_lock);
 126
 127         d->flags = flags;
 128         if (flags & SKBEDIT_F_PRIORITY)
 129                 d->priority = *priority;
 130         if (flags & SKBEDIT_F_QUEUE_MAPPING)
 131                 d->queue_mapping = *queue_mapping;
 132         if (flags & SKBEDIT_F_MARK)
 133                 d->mark = *mark;
 134
 135         d->tcf_action = parm->action;
 136
 137         spin_unlock_bh(&d->tcf_lock);
 138
 139         if (ret == ACT_P_CREATED)
 140                 tcf_hash_insert(tn, a);
 141         return ret;
 142 }
 143
 144 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
 145                             int bind, int ref)
 146 {
 147         unsigned char *b = skb_tail_pointer(skb);
 148         struct tcf_skbedit *d = a->priv;
 149         struct tc_skbedit opt = {
 150                 .index   = d->tcf_index,
 151                 .refcnt  = d->tcf_refcnt - ref,
 152                 .bindcnt = d->tcf_bindcnt - bind,
 153                 .action  = d->tcf_action,
 154         };
 155         struct tcf_t t;
 156
 157         if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
 158                 goto nla_put_failure;
 159         if ((d->flags & SKBEDIT_F_PRIORITY) &&
 160             nla_put(skb, TCA_SKBEDIT_PRIORITY, sizeof(d->priority),
 161                     &d->priority))
 162                 goto nla_put_failure;
 163         if ((d->flags & SKBEDIT_F_QUEUE_MAPPING) &&
 164             nla_put(skb, TCA_SKBEDIT_QUEUE_MAPPING,
 165                     sizeof(d->queue_mapping), &d->queue_mapping))
 166                 goto nla_put_failure;
 167         if ((d->flags & SKBEDIT_F_MARK) &&
 168             nla_put(skb, TCA_SKBEDIT_MARK, sizeof(d->mark),
 169                     &d->mark))
 170                 goto nla_put_failure;
 171         t.install = jiffies_to_clock_t(jiffies - d->tcf_tm.install);
 172         t.lastuse = jiffies_to_clock_t(jiffies - d->tcf_tm.lastuse);
 173         t.expires = jiffies_to_clock_t(d->tcf_tm.expires);
 174         if (nla_put_64bit(skb, TCA_SKBEDIT_TM, sizeof(t), &t, TCA_SKBEDIT_PAD))
 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 int tcf_skbedit_walker(struct net *net, struct sk_buff *skb,
 184                               struct netlink_callback *cb, int type,
 185                               struct tc_action *a)
 186 {
 187         struct tc_action_net *tn = net_generic(net, skbedit_net_id);
 188
 189         return tcf_generic_walker(tn, skb, cb, type, a);
 190 }
 191
 192 static int tcf_skbedit_search(struct net *net, struct tc_action *a, u32 index)
 193 {
 194         struct tc_action_net *tn = net_generic(net, skbedit_net_id);
 195
 196         return tcf_hash_search(tn, a, index);
 197 }
 198
 199 static struct tc_action_ops act_skbedit_ops = {
 200         .kind           =       "skbedit",
 201         .type           =       TCA_ACT_SKBEDIT,
 202         .owner          =       THIS_MODULE,
 203         .act            =       tcf_skbedit,
 204         .dump           =       tcf_skbedit_dump,
 205         .init           =       tcf_skbedit_init,
 206         .walk           =       tcf_skbedit_walker,
 207         .lookup         =       tcf_skbedit_search,
 208 };
 209
 210 static __net_init int skbedit_init_net(struct net *net)
 211 {
 212         struct tc_action_net *tn = net_generic(net, skbedit_net_id);
 213
 214         return tc_action_net_init(tn, &act_skbedit_ops, SKBEDIT_TAB_MASK);
 215 }
 216
 217 static void __net_exit skbedit_exit_net(struct net *net)
 218 {
 219         struct tc_action_net *tn = net_generic(net, skbedit_net_id);
 220
 221         tc_action_net_exit(tn);
 222 }
 223
 224 static struct pernet_operations skbedit_net_ops = {
 225         .init = skbedit_init_net,
 226         .exit = skbedit_exit_net,
 227         .id   = &skbedit_net_id,
 228         .size = sizeof(struct tc_action_net),
 229 };
 230
 231 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
 232 MODULE_DESCRIPTION("SKB Editing");
 233 MODULE_LICENSE("GPL");
 234
 235 static int __init skbedit_init_module(void)
 236 {
 237         return tcf_register_action(&act_skbedit_ops, &skbedit_net_ops);
 238 }
 239
 240 static void __exit skbedit_cleanup_module(void)
 241 {
 242         tcf_unregister_action(&act_skbedit_ops, &skbedit_net_ops);
 243 }
 244
 245 module_init(skbedit_init_module);
 246 module_exit(skbedit_cleanup_module);