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 static unsigned int skbedit_net_id;
  31 static struct tc_action_ops act_skbedit_ops;
  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 = to_skbedit(a);
  37
  38         spin_lock(&d->tcf_lock);
  39         tcf_lastuse_update(&d->tcf_tm);
  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->mask;
  49                 skb->mark |= d->mark & d->mask;
  50         }
  51         if (d->flags & SKBEDIT_F_PTYPE)
  52                 skb->pkt_type = d->ptype;
  53
  54         spin_unlock(&d->tcf_lock);
  55         return d->tcf_action;
  56 }
  57
  58 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
  59         [TCA_SKBEDIT_PARMS]             = { .len = sizeof(struct tc_skbedit) },
  60         [TCA_SKBEDIT_PRIORITY]          = { .len = sizeof(u32) },
  61         [TCA_SKBEDIT_QUEUE_MAPPING]     = { .len = sizeof(u16) },
  62         [TCA_SKBEDIT_MARK]              = { .len = sizeof(u32) },
  63         [TCA_SKBEDIT_PTYPE]             = { .len = sizeof(u16) },
  64         [TCA_SKBEDIT_MASK]              = { .len = sizeof(u32) },
  65 };
  66
  67 static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
  68                             struct nlattr *est, struct tc_action **a,
  69                             int ovr, int bind)
  70 {
  71         struct tc_action_net *tn = net_generic(net, skbedit_net_id);
  72         struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
  73         struct tc_skbedit *parm;
  74         struct tcf_skbedit *d;
  75         u32 flags = 0, *priority = NULL, *mark = NULL, *mask = NULL;
  76         u16 *queue_mapping = NULL, *ptype = NULL;
  77         bool exists = false;
  78         int ret = 0, err;
  79
  80         if (nla == NULL)
  81                 return -EINVAL;
  82
  83         err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy, NULL);
  84         if (err < 0)
  85                 return err;
  86
  87         if (tb[TCA_SKBEDIT_PARMS] == NULL)
  88                 return -EINVAL;
  89
  90         if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
  91                 flags |= SKBEDIT_F_PRIORITY;
  92                 priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
  93         }
  94
  95         if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
  96                 flags |= SKBEDIT_F_QUEUE_MAPPING;
  97                 queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
  98         }
  99
 100         if (tb[TCA_SKBEDIT_PTYPE] != NULL) {
 101                 ptype = nla_data(tb[TCA_SKBEDIT_PTYPE]);
 102                 if (!skb_pkt_type_ok(*ptype))
 103                         return -EINVAL;
 104                 flags |= SKBEDIT_F_PTYPE;
 105         }
 106
 107         if (tb[TCA_SKBEDIT_MARK] != NULL) {
 108                 flags |= SKBEDIT_F_MARK;
 109                 mark = nla_data(tb[TCA_SKBEDIT_MARK]);
 110         }
 111
 112         if (tb[TCA_SKBEDIT_MASK] != NULL) {
 113                 flags |= SKBEDIT_F_MASK;
 114                 mask = nla_data(tb[TCA_SKBEDIT_MASK]);
 115         }
 116
 117         parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
 118
 119         exists = tcf_idr_check(tn, parm->index, a, bind);
 120         if (exists && bind)
 121                 return 0;
 122
 123         if (!flags) {
 124                 if (exists)
 125                         tcf_idr_release(*a, bind);
 126                 return -EINVAL;
 127         }
 128
 129         if (!exists) {
 130                 ret = tcf_idr_create(tn, parm->index, est, a,
 131                                      &act_skbedit_ops, bind, false);
 132                 if (ret)
 133                         return ret;
 134
 135                 d = to_skbedit(*a);
 136                 ret = ACT_P_CREATED;
 137         } else {
 138                 d = to_skbedit(*a);
 139                 tcf_idr_release(*a, bind);
 140                 if (!ovr)
 141                         return -EEXIST;
 142         }
 143
 144         spin_lock_bh(&d->tcf_lock);
 145
 146         d->flags = flags;
 147         if (flags & SKBEDIT_F_PRIORITY)
 148                 d->priority = *priority;
 149         if (flags & SKBEDIT_F_QUEUE_MAPPING)
 150                 d->queue_mapping = *queue_mapping;
 151         if (flags & SKBEDIT_F_MARK)
 152                 d->mark = *mark;
 153         if (flags & SKBEDIT_F_PTYPE)
 154                 d->ptype = *ptype;
 155         /* default behaviour is to use all the bits */
 156         d->mask = 0xffffffff;
 157         if (flags & SKBEDIT_F_MASK)
 158                 d->mask = *mask;
 159
 160         d->tcf_action = parm->action;
 161
 162         spin_unlock_bh(&d->tcf_lock);
 163
 164         if (ret == ACT_P_CREATED)
 165                 tcf_idr_insert(tn, *a);
 166         return ret;
 167 }
 168
 169 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
 170                             int bind, int ref)
 171 {
 172         unsigned char *b = skb_tail_pointer(skb);
 173         struct tcf_skbedit *d = to_skbedit(a);
 174         struct tc_skbedit opt = {
 175                 .index   = d->tcf_index,
 176                 .refcnt  = d->tcf_refcnt - ref,
 177                 .bindcnt = d->tcf_bindcnt - bind,
 178                 .action  = d->tcf_action,
 179         };
 180         struct tcf_t t;
 181
 182         if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
 183                 goto nla_put_failure;
 184         if ((d->flags & SKBEDIT_F_PRIORITY) &&
 185             nla_put_u32(skb, TCA_SKBEDIT_PRIORITY, d->priority))
 186                 goto nla_put_failure;
 187         if ((d->flags & SKBEDIT_F_QUEUE_MAPPING) &&
 188             nla_put_u16(skb, TCA_SKBEDIT_QUEUE_MAPPING, d->queue_mapping))
 189                 goto nla_put_failure;
 190         if ((d->flags & SKBEDIT_F_MARK) &&
 191             nla_put_u32(skb, TCA_SKBEDIT_MARK, d->mark))
 192                 goto nla_put_failure;
 193         if ((d->flags & SKBEDIT_F_PTYPE) &&
 194             nla_put_u16(skb, TCA_SKBEDIT_PTYPE, d->ptype))
 195                 goto nla_put_failure;
 196         if ((d->flags & SKBEDIT_F_MASK) &&
 197             nla_put_u32(skb, TCA_SKBEDIT_MASK, d->mask))
 198                 goto nla_put_failure;
 199
 200         tcf_tm_dump(&t, &d->tcf_tm);
 201         if (nla_put_64bit(skb, TCA_SKBEDIT_TM, sizeof(t), &t, TCA_SKBEDIT_PAD))
 202                 goto nla_put_failure;
 203         return skb->len;
 204
 205 nla_put_failure:
 206         nlmsg_trim(skb, b);
 207         return -1;
 208 }
 209
 210 static int tcf_skbedit_walker(struct net *net, struct sk_buff *skb,
 211                               struct netlink_callback *cb, int type,
 212                               const struct tc_action_ops *ops)
 213 {
 214         struct tc_action_net *tn = net_generic(net, skbedit_net_id);
 215
 216         return tcf_generic_walker(tn, skb, cb, type, ops);
 217 }
 218
 219 static int tcf_skbedit_search(struct net *net, struct tc_action **a, u32 index)
 220 {
 221         struct tc_action_net *tn = net_generic(net, skbedit_net_id);
 222
 223         return tcf_idr_search(tn, a, index);
 224 }
 225
 226 static struct tc_action_ops act_skbedit_ops = {
 227         .kind           =       "skbedit",
 228         .type           =       TCA_ACT_SKBEDIT,
 229         .owner          =       THIS_MODULE,
 230         .act            =       tcf_skbedit,
 231         .dump           =       tcf_skbedit_dump,
 232         .init           =       tcf_skbedit_init,
 233         .walk           =       tcf_skbedit_walker,
 234         .lookup         =       tcf_skbedit_search,
 235         .size           =       sizeof(struct tcf_skbedit),
 236 };
 237
 238 static __net_init int skbedit_init_net(struct net *net)
 239 {
 240         struct tc_action_net *tn = net_generic(net, skbedit_net_id);
 241
 242         return tc_action_net_init(tn, &act_skbedit_ops);
 243 }
 244
 245 static void __net_exit skbedit_exit_net(struct net *net)
 246 {
 247         struct tc_action_net *tn = net_generic(net, skbedit_net_id);
 248
 249         tc_action_net_exit(tn);
 250 }
 251
 252 static struct pernet_operations skbedit_net_ops = {
 253         .init = skbedit_init_net,
 254         .exit = skbedit_exit_net,
 255         .id   = &skbedit_net_id,
 256         .size = sizeof(struct tc_action_net),
 257 };
 258
 259 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
 260 MODULE_DESCRIPTION("SKB Editing");
 261 MODULE_LICENSE("GPL");
 262
 263 static int __init skbedit_init_module(void)
 264 {
 265         return tcf_register_action(&act_skbedit_ops, &skbedit_net_ops);
 266 }
 267
 268 static void __exit skbedit_cleanup_module(void)
 269 {
 270         tcf_unregister_action(&act_skbedit_ops, &skbedit_net_ops);
 271 }
 272
 273 module_init(skbedit_init_module);
 274 module_exit(skbedit_cleanup_module);