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 unsigned int skbedit_net_id;
  33 static struct tc_action_ops act_skbedit_ops;
  34
  35 static int tcf_skbedit(struct sk_buff *skb, const struct tc_action *a,
  36                        struct tcf_result *res)
  37 {
  38         struct tcf_skbedit *d = to_skbedit(a);
  39
  40         spin_lock(&d->tcf_lock);
  41         tcf_lastuse_update(&d->tcf_tm);
  42         bstats_update(&d->tcf_bstats, skb);
  43
  44         if (d->flags & SKBEDIT_F_PRIORITY)
  45                 skb->priority = d->priority;
  46         if (d->flags & SKBEDIT_F_QUEUE_MAPPING &&
  47             skb->dev->real_num_tx_queues > d->queue_mapping)
  48                 skb_set_queue_mapping(skb, d->queue_mapping);
  49         if (d->flags & SKBEDIT_F_MARK) {
  50                 skb->mark &= ~d->mask;
  51                 skb->mark |= d->mark & d->mask;
  52         }
  53         if (d->flags & SKBEDIT_F_PTYPE)
  54                 skb->pkt_type = d->ptype;
  55
  56         spin_unlock(&d->tcf_lock);
  57         return d->tcf_action;
  58 }
  59
  60 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
  61         [TCA_SKBEDIT_PARMS]             = { .len = sizeof(struct tc_skbedit) },
  62         [TCA_SKBEDIT_PRIORITY]          = { .len = sizeof(u32) },
  63         [TCA_SKBEDIT_QUEUE_MAPPING]     = { .len = sizeof(u16) },
  64         [TCA_SKBEDIT_MARK]              = { .len = sizeof(u32) },
  65         [TCA_SKBEDIT_PTYPE]             = { .len = sizeof(u16) },
  66         [TCA_SKBEDIT_MASK]              = { .len = sizeof(u32) },
  67 };
  68
  69 static int tcf_skbedit_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, skbedit_net_id);
  74         struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
  75         struct tc_skbedit *parm;
  76         struct tcf_skbedit *d;
  77         u32 flags = 0, *priority = NULL, *mark = NULL, *mask = NULL;
  78         u16 *queue_mapping = NULL, *ptype = NULL;
  79         bool exists = false;
  80         int ret = 0, err;
  81
  82         if (nla == NULL)
  83                 return -EINVAL;
  84
  85         err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy);
  86         if (err < 0)
  87                 return err;
  88
  89         if (tb[TCA_SKBEDIT_PARMS] == NULL)
  90                 return -EINVAL;
  91
  92         if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
  93                 flags |= SKBEDIT_F_PRIORITY;
  94                 priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
  95         }
  96
  97         if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
  98                 flags |= SKBEDIT_F_QUEUE_MAPPING;
  99                 queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
 100         }
 101
 102         if (tb[TCA_SKBEDIT_PTYPE] != NULL) {
 103                 ptype = nla_data(tb[TCA_SKBEDIT_PTYPE]);
 104                 if (!skb_pkt_type_ok(*ptype))
 105                         return -EINVAL;
 106                 flags |= SKBEDIT_F_PTYPE;
 107         }
 108
 109         if (tb[TCA_SKBEDIT_MARK] != NULL) {
 110                 flags |= SKBEDIT_F_MARK;
 111                 mark = nla_data(tb[TCA_SKBEDIT_MARK]);
 112         }
 113
 114         if (tb[TCA_SKBEDIT_MASK] != NULL) {
 115                 flags |= SKBEDIT_F_MASK;
 116                 mask = nla_data(tb[TCA_SKBEDIT_MASK]);
 117         }
 118
 119         parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
 120
 121         exists = tcf_hash_check(tn, parm->index, a, bind);
 122         if (exists && bind)
 123                 return 0;
 124
 125         if (!flags) {
 126                 tcf_hash_release(*a, bind);
 127                 return -EINVAL;
 128         }
 129
 130         if (!exists) {
 131                 ret = tcf_hash_create(tn, parm->index, est, a,
 132                                       &act_skbedit_ops, bind, false);
 133                 if (ret)
 134                         return ret;
 135
 136                 d = to_skbedit(*a);
 137                 ret = ACT_P_CREATED;
 138         } else {
 139                 d = to_skbedit(*a);
 140                 tcf_hash_release(*a, bind);
 141                 if (!ovr)
 142                         return -EEXIST;
 143         }
 144
 145         spin_lock_bh(&d->tcf_lock);
 146
 147         d->flags = flags;
 148         if (flags & SKBEDIT_F_PRIORITY)
 149                 d->priority = *priority;
 150         if (flags & SKBEDIT_F_QUEUE_MAPPING)
 151                 d->queue_mapping = *queue_mapping;
 152         if (flags & SKBEDIT_F_MARK)
 153                 d->mark = *mark;
 154         if (flags & SKBEDIT_F_PTYPE)
 155                 d->ptype = *ptype;
 156         /* default behaviour is to use all the bits */
 157         d->mask = 0xffffffff;
 158         if (flags & SKBEDIT_F_MASK)
 159                 d->mask = *mask;
 160
 161         d->tcf_action = parm->action;
 162
 163         spin_unlock_bh(&d->tcf_lock);
 164
 165         if (ret == ACT_P_CREATED)
 166                 tcf_hash_insert(tn, *a);
 167         return ret;
 168 }
 169
 170 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
 171                             int bind, int ref)
 172 {
 173         unsigned char *b = skb_tail_pointer(skb);
 174         struct tcf_skbedit *d = to_skbedit(a);
 175         struct tc_skbedit opt = {
 176                 .index   = d->tcf_index,
 177                 .refcnt  = d->tcf_refcnt - ref,
 178                 .bindcnt = d->tcf_bindcnt - bind,
 179                 .action  = d->tcf_action,
 180         };
 181         struct tcf_t t;
 182
 183         if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
 184                 goto nla_put_failure;
 185         if ((d->flags & SKBEDIT_F_PRIORITY) &&
 186             nla_put_u32(skb, TCA_SKBEDIT_PRIORITY, d->priority))
 187                 goto nla_put_failure;
 188         if ((d->flags & SKBEDIT_F_QUEUE_MAPPING) &&
 189             nla_put_u16(skb, TCA_SKBEDIT_QUEUE_MAPPING, d->queue_mapping))
 190                 goto nla_put_failure;
 191         if ((d->flags & SKBEDIT_F_MARK) &&
 192             nla_put_u32(skb, TCA_SKBEDIT_MARK, d->mark))
 193                 goto nla_put_failure;
 194         if ((d->flags & SKBEDIT_F_PTYPE) &&
 195             nla_put_u16(skb, TCA_SKBEDIT_PTYPE, d->ptype))
 196                 goto nla_put_failure;
 197         if ((d->flags & SKBEDIT_F_MASK) &&
 198             nla_put_u32(skb, TCA_SKBEDIT_MASK, d->mask))
 199                 goto nla_put_failure;
 200
 201         tcf_tm_dump(&t, &d->tcf_tm);
 202         if (nla_put_64bit(skb, TCA_SKBEDIT_TM, sizeof(t), &t, TCA_SKBEDIT_PAD))
 203                 goto nla_put_failure;
 204         return skb->len;
 205
 206 nla_put_failure:
 207         nlmsg_trim(skb, b);
 208         return -1;
 209 }
 210
 211 static int tcf_skbedit_walker(struct net *net, struct sk_buff *skb,
 212                               struct netlink_callback *cb, int type,
 213                               const struct tc_action_ops *ops)
 214 {
 215         struct tc_action_net *tn = net_generic(net, skbedit_net_id);
 216
 217         return tcf_generic_walker(tn, skb, cb, type, ops);
 218 }
 219
 220 static int tcf_skbedit_search(struct net *net, struct tc_action **a, u32 index)
 221 {
 222         struct tc_action_net *tn = net_generic(net, skbedit_net_id);
 223
 224         return tcf_hash_search(tn, a, index);
 225 }
 226
 227 static struct tc_action_ops act_skbedit_ops = {
 228         .kind           =       "skbedit",
 229         .type           =       TCA_ACT_SKBEDIT,
 230         .owner          =       THIS_MODULE,
 231         .act            =       tcf_skbedit,
 232         .dump           =       tcf_skbedit_dump,
 233         .init           =       tcf_skbedit_init,
 234         .walk           =       tcf_skbedit_walker,
 235         .lookup         =       tcf_skbedit_search,
 236         .size           =       sizeof(struct tcf_skbedit),
 237 };
 238
 239 static __net_init int skbedit_init_net(struct net *net)
 240 {
 241         struct tc_action_net *tn = net_generic(net, skbedit_net_id);
 242
 243         return tc_action_net_init(tn, &act_skbedit_ops, SKBEDIT_TAB_MASK);
 244 }
 245
 246 static void __net_exit skbedit_exit_net(struct net *net)
 247 {
 248         struct tc_action_net *tn = net_generic(net, skbedit_net_id);
 249
 250         tc_action_net_exit(tn);
 251 }
 252
 253 static struct pernet_operations skbedit_net_ops = {
 254         .init = skbedit_init_net,
 255         .exit = skbedit_exit_net,
 256         .id   = &skbedit_net_id,
 257         .size = sizeof(struct tc_action_net),
 258 };
 259
 260 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
 261 MODULE_DESCRIPTION("SKB Editing");
 262 MODULE_LICENSE("GPL");
 263
 264 static int __init skbedit_init_module(void)
 265 {
 266         return tcf_register_action(&act_skbedit_ops, &skbedit_net_ops);
 267 }
 268
 269 static void __exit skbedit_cleanup_module(void)
 270 {
 271         tcf_unregister_action(&act_skbedit_ops, &skbedit_net_ops);
 272 }
 273
 274 module_init(skbedit_init_module);
 275 module_exit(skbedit_cleanup_module);