blob: e43c56d5b96a2943d59733185b51b8bafe19f8fa [file] [log] [blame]
/*
* net/sched/cls_basic.c Basic Packet Classifier.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* Authors: Thomas Graf <tgraf@suug.ch>
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/rtnetlink.h>
#include <linux/skbuff.h>
#include <net/netlink.h>
#include <net/act_api.h>
#include <net/pkt_cls.h>
struct basic_head {
u32 hgenerator;
struct list_head flist;
struct rcu_head rcu;
};
struct basic_filter {
u32 handle;
struct tcf_exts exts;
struct tcf_ematch_tree ematches;
struct tcf_result res;
struct tcf_proto *tp;
struct list_head link;
union {
struct work_struct work;
struct rcu_head rcu;
};
};
static int basic_classify(struct sk_buff *skb, const struct tcf_proto *tp,
struct tcf_result *res)
{
int r;
struct basic_head *head = rcu_dereference_bh(tp->root);
struct basic_filter *f;
list_for_each_entry_rcu(f, &head->flist, link) {
if (!tcf_em_tree_match(skb, &f->ematches, NULL))
continue;
*res = f->res;
r = tcf_exts_exec(skb, &f->exts, res);
if (r < 0)
continue;
return r;
}
return -1;
}
static void *basic_get(struct tcf_proto *tp, u32 handle)
{
struct basic_head *head = rtnl_dereference(tp->root);
struct basic_filter *f;
list_for_each_entry(f, &head->flist, link) {
if (f->handle == handle) {
return f;
}
}
return NULL;
}
static int basic_init(struct tcf_proto *tp)
{
struct basic_head *head;
head = kzalloc(sizeof(*head), GFP_KERNEL);
if (head == NULL)
return -ENOBUFS;
INIT_LIST_HEAD(&head->flist);
rcu_assign_pointer(tp->root, head);
return 0;
}
static void __basic_delete_filter(struct basic_filter *f)
{
tcf_exts_destroy(&f->exts);
tcf_em_tree_destroy(&f->ematches);
tcf_exts_put_net(&f->exts);
kfree(f);
}
static void basic_delete_filter_work(struct work_struct *work)
{
struct basic_filter *f = container_of(work, struct basic_filter, work);
rtnl_lock();
__basic_delete_filter(f);
rtnl_unlock();
}
static void basic_delete_filter(struct rcu_head *head)
{
struct basic_filter *f = container_of(head, struct basic_filter, rcu);
INIT_WORK(&f->work, basic_delete_filter_work);
tcf_queue_work(&f->work);
}
static void basic_destroy(struct tcf_proto *tp)
{
struct basic_head *head = rtnl_dereference(tp->root);
struct basic_filter *f, *n;
list_for_each_entry_safe(f, n, &head->flist, link) {
list_del_rcu(&f->link);
tcf_unbind_filter(tp, &f->res);
if (tcf_exts_get_net(&f->exts))
call_rcu(&f->rcu, basic_delete_filter);
else
__basic_delete_filter(f);
}
kfree_rcu(head, rcu);
}
static int basic_delete(struct tcf_proto *tp, void *arg, bool *last)
{
struct basic_head *head = rtnl_dereference(tp->root);
struct basic_filter *f = arg;
list_del_rcu(&f->link);
tcf_unbind_filter(tp, &f->res);
tcf_exts_get_net(&f->exts);
call_rcu(&f->rcu, basic_delete_filter);
*last = list_empty(&head->flist);
return 0;
}
static const struct nla_policy basic_policy[TCA_BASIC_MAX + 1] = {
[TCA_BASIC_CLASSID] = { .type = NLA_U32 },
[TCA_BASIC_EMATCHES] = { .type = NLA_NESTED },
};
static int basic_set_parms(struct net *net, struct tcf_proto *tp,
struct basic_filter *f, unsigned long base,
struct nlattr **tb,
struct nlattr *est, bool ovr)
{
int err;
err = tcf_exts_validate(net, tp, tb, est, &f->exts, ovr);
if (err < 0)
return err;
err = tcf_em_tree_validate(tp, tb[TCA_BASIC_EMATCHES], &f->ematches);
if (err < 0)
return err;
if (tb[TCA_BASIC_CLASSID]) {
f->res.classid = nla_get_u32(tb[TCA_BASIC_CLASSID]);
tcf_bind_filter(tp, &f->res, base);
}
f->tp = tp;
return 0;
}
static int basic_change(struct net *net, struct sk_buff *in_skb,
struct tcf_proto *tp, unsigned long base, u32 handle,
struct nlattr **tca, void **arg, bool ovr)
{
int err;
struct basic_head *head = rtnl_dereference(tp->root);
struct nlattr *tb[TCA_BASIC_MAX + 1];
struct basic_filter *fold = (struct basic_filter *) *arg;
struct basic_filter *fnew;
if (tca[TCA_OPTIONS] == NULL)
return -EINVAL;
err = nla_parse_nested(tb, TCA_BASIC_MAX, tca[TCA_OPTIONS],
basic_policy, NULL);
if (err < 0)
return err;
if (fold != NULL) {
if (handle && fold->handle != handle)
return -EINVAL;
}
fnew = kzalloc(sizeof(*fnew), GFP_KERNEL);
if (!fnew)
return -ENOBUFS;
err = tcf_exts_init(&fnew->exts, TCA_BASIC_ACT, TCA_BASIC_POLICE);
if (err < 0)
goto errout;
err = -EINVAL;
if (handle) {
fnew->handle = handle;
} else if (fold) {
fnew->handle = fold->handle;
} else {
unsigned int i = 0x80000000;
do {
if (++head->hgenerator == 0x7FFFFFFF)
head->hgenerator = 1;
} while (--i > 0 && basic_get(tp, head->hgenerator));
if (i <= 0) {
pr_err("Insufficient number of handles\n");
goto errout;
}
fnew->handle = head->hgenerator;
}
err = basic_set_parms(net, tp, fnew, base, tb, tca[TCA_RATE], ovr);
if (err < 0)
goto errout;
*arg = fnew;
if (fold) {
list_replace_rcu(&fold->link, &fnew->link);
tcf_unbind_filter(tp, &fold->res);
tcf_exts_get_net(&fold->exts);
call_rcu(&fold->rcu, basic_delete_filter);
} else {
list_add_rcu(&fnew->link, &head->flist);
}
return 0;
errout:
tcf_exts_destroy(&fnew->exts);
kfree(fnew);
return err;
}
static void basic_walk(struct tcf_proto *tp, struct tcf_walker *arg)
{
struct basic_head *head = rtnl_dereference(tp->root);
struct basic_filter *f;
list_for_each_entry(f, &head->flist, link) {
if (arg->count < arg->skip)
goto skip;
if (arg->fn(tp, f, arg) < 0) {
arg->stop = 1;
break;
}
skip:
arg->count++;
}
}
static void basic_bind_class(void *fh, u32 classid, unsigned long cl)
{
struct basic_filter *f = fh;
if (f && f->res.classid == classid)
f->res.class = cl;
}
static int basic_dump(struct net *net, struct tcf_proto *tp, void *fh,
struct sk_buff *skb, struct tcmsg *t)
{
struct basic_filter *f = fh;
struct nlattr *nest;
if (f == NULL)
return skb->len;
t->tcm_handle = f->handle;
nest = nla_nest_start(skb, TCA_OPTIONS);
if (nest == NULL)
goto nla_put_failure;
if (f->res.classid &&
nla_put_u32(skb, TCA_BASIC_CLASSID, f->res.classid))
goto nla_put_failure;
if (tcf_exts_dump(skb, &f->exts) < 0 ||
tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0)
goto nla_put_failure;
nla_nest_end(skb, nest);
if (tcf_exts_dump_stats(skb, &f->exts) < 0)
goto nla_put_failure;
return skb->len;
nla_put_failure:
nla_nest_cancel(skb, nest);
return -1;
}
static struct tcf_proto_ops cls_basic_ops __read_mostly = {
.kind = "basic",
.classify = basic_classify,
.init = basic_init,
.destroy = basic_destroy,
.get = basic_get,
.change = basic_change,
.delete = basic_delete,
.walk = basic_walk,
.dump = basic_dump,
.bind_class = basic_bind_class,
.owner = THIS_MODULE,
};
static int __init init_basic(void)
{
return register_tcf_proto_ops(&cls_basic_ops);
}
static void __exit exit_basic(void)
{
unregister_tcf_proto_ops(&cls_basic_ops);
}
module_init(init_basic)
module_exit(exit_basic)
MODULE_LICENSE("GPL");