linux/net/sched/cls_fw.c
Jiri Pirko a51486266c net: sched: remove NET_CLS_IND config option
This config option makes only couple of lines optional.
Two small helpers and an int in couple of cls structs.

Remove the config option and always compile this in.
This saves the user from unexpected surprises when he adds
a filter with ingress device match which is silently ignored
in case the config option is not set.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-15 14:06:13 -07:00

457 lines
9.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* net/sched/cls_fw.c Classifier mapping ipchains' fwmark to traffic class.
*
* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
*
* Changes:
* Karlis Peisenieks <karlis@mt.lv> : 990415 : fw_walk off by one
* Karlis Peisenieks <karlis@mt.lv> : 990415 : fw_delete killed all the filter (and kernel).
* Alex <alex@pilotsoft.com> : 2004xxyy: Added Action extension
*/
#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/skbuff.h>
#include <net/netlink.h>
#include <net/act_api.h>
#include <net/pkt_cls.h>
#include <net/sch_generic.h>
#define HTSIZE 256
struct fw_head {
u32 mask;
struct fw_filter __rcu *ht[HTSIZE];
struct rcu_head rcu;
};
struct fw_filter {
struct fw_filter __rcu *next;
u32 id;
struct tcf_result res;
int ifindex;
struct tcf_exts exts;
struct tcf_proto *tp;
struct rcu_work rwork;
};
static u32 fw_hash(u32 handle)
{
handle ^= (handle >> 16);
handle ^= (handle >> 8);
return handle % HTSIZE;
}
static int fw_classify(struct sk_buff *skb, const struct tcf_proto *tp,
struct tcf_result *res)
{
struct fw_head *head = rcu_dereference_bh(tp->root);
struct fw_filter *f;
int r;
u32 id = skb->mark;
if (head != NULL) {
id &= head->mask;
for (f = rcu_dereference_bh(head->ht[fw_hash(id)]); f;
f = rcu_dereference_bh(f->next)) {
if (f->id == id) {
*res = f->res;
if (!tcf_match_indev(skb, f->ifindex))
continue;
r = tcf_exts_exec(skb, &f->exts, res);
if (r < 0)
continue;
return r;
}
}
} else {
struct Qdisc *q = tcf_block_q(tp->chain->block);
/* Old method: classify the packet using its skb mark. */
if (id && (TC_H_MAJ(id) == 0 ||
!(TC_H_MAJ(id ^ q->handle)))) {
res->classid = id;
res->class = 0;
return 0;
}
}
return -1;
}
static void *fw_get(struct tcf_proto *tp, u32 handle)
{
struct fw_head *head = rtnl_dereference(tp->root);
struct fw_filter *f;
if (head == NULL)
return NULL;
f = rtnl_dereference(head->ht[fw_hash(handle)]);
for (; f; f = rtnl_dereference(f->next)) {
if (f->id == handle)
return f;
}
return NULL;
}
static int fw_init(struct tcf_proto *tp)
{
/* We don't allocate fw_head here, because in the old method
* we don't need it at all.
*/
return 0;
}
static void __fw_delete_filter(struct fw_filter *f)
{
tcf_exts_destroy(&f->exts);
tcf_exts_put_net(&f->exts);
kfree(f);
}
static void fw_delete_filter_work(struct work_struct *work)
{
struct fw_filter *f = container_of(to_rcu_work(work),
struct fw_filter,
rwork);
rtnl_lock();
__fw_delete_filter(f);
rtnl_unlock();
}
static void fw_destroy(struct tcf_proto *tp, bool rtnl_held,
struct netlink_ext_ack *extack)
{
struct fw_head *head = rtnl_dereference(tp->root);
struct fw_filter *f;
int h;
if (head == NULL)
return;
for (h = 0; h < HTSIZE; h++) {
while ((f = rtnl_dereference(head->ht[h])) != NULL) {
RCU_INIT_POINTER(head->ht[h],
rtnl_dereference(f->next));
tcf_unbind_filter(tp, &f->res);
if (tcf_exts_get_net(&f->exts))
tcf_queue_work(&f->rwork, fw_delete_filter_work);
else
__fw_delete_filter(f);
}
}
kfree_rcu(head, rcu);
}
static int fw_delete(struct tcf_proto *tp, void *arg, bool *last,
bool rtnl_held, struct netlink_ext_ack *extack)
{
struct fw_head *head = rtnl_dereference(tp->root);
struct fw_filter *f = arg;
struct fw_filter __rcu **fp;
struct fw_filter *pfp;
int ret = -EINVAL;
int h;
if (head == NULL || f == NULL)
goto out;
fp = &head->ht[fw_hash(f->id)];
for (pfp = rtnl_dereference(*fp); pfp;
fp = &pfp->next, pfp = rtnl_dereference(*fp)) {
if (pfp == f) {
RCU_INIT_POINTER(*fp, rtnl_dereference(f->next));
tcf_unbind_filter(tp, &f->res);
tcf_exts_get_net(&f->exts);
tcf_queue_work(&f->rwork, fw_delete_filter_work);
ret = 0;
break;
}
}
*last = true;
for (h = 0; h < HTSIZE; h++) {
if (rcu_access_pointer(head->ht[h])) {
*last = false;
break;
}
}
out:
return ret;
}
static const struct nla_policy fw_policy[TCA_FW_MAX + 1] = {
[TCA_FW_CLASSID] = { .type = NLA_U32 },
[TCA_FW_INDEV] = { .type = NLA_STRING, .len = IFNAMSIZ },
[TCA_FW_MASK] = { .type = NLA_U32 },
};
static int fw_set_parms(struct net *net, struct tcf_proto *tp,
struct fw_filter *f, struct nlattr **tb,
struct nlattr **tca, unsigned long base, bool ovr,
struct netlink_ext_ack *extack)
{
struct fw_head *head = rtnl_dereference(tp->root);
u32 mask;
int err;
err = tcf_exts_validate(net, tp, tb, tca[TCA_RATE], &f->exts, ovr,
true, extack);
if (err < 0)
return err;
if (tb[TCA_FW_CLASSID]) {
f->res.classid = nla_get_u32(tb[TCA_FW_CLASSID]);
tcf_bind_filter(tp, &f->res, base);
}
if (tb[TCA_FW_INDEV]) {
int ret;
ret = tcf_change_indev(net, tb[TCA_FW_INDEV], extack);
if (ret < 0)
return ret;
f->ifindex = ret;
}
err = -EINVAL;
if (tb[TCA_FW_MASK]) {
mask = nla_get_u32(tb[TCA_FW_MASK]);
if (mask != head->mask)
return err;
} else if (head->mask != 0xFFFFFFFF)
return err;
return 0;
}
static int fw_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, bool rtnl_held,
struct netlink_ext_ack *extack)
{
struct fw_head *head = rtnl_dereference(tp->root);
struct fw_filter *f = *arg;
struct nlattr *opt = tca[TCA_OPTIONS];
struct nlattr *tb[TCA_FW_MAX + 1];
int err;
if (!opt)
return handle ? -EINVAL : 0; /* Succeed if it is old method. */
err = nla_parse_nested_deprecated(tb, TCA_FW_MAX, opt, fw_policy,
NULL);
if (err < 0)
return err;
if (f) {
struct fw_filter *pfp, *fnew;
struct fw_filter __rcu **fp;
if (f->id != handle && handle)
return -EINVAL;
fnew = kzalloc(sizeof(struct fw_filter), GFP_KERNEL);
if (!fnew)
return -ENOBUFS;
fnew->id = f->id;
fnew->res = f->res;
fnew->ifindex = f->ifindex;
fnew->tp = f->tp;
err = tcf_exts_init(&fnew->exts, net, TCA_FW_ACT,
TCA_FW_POLICE);
if (err < 0) {
kfree(fnew);
return err;
}
err = fw_set_parms(net, tp, fnew, tb, tca, base, ovr, extack);
if (err < 0) {
tcf_exts_destroy(&fnew->exts);
kfree(fnew);
return err;
}
fp = &head->ht[fw_hash(fnew->id)];
for (pfp = rtnl_dereference(*fp); pfp;
fp = &pfp->next, pfp = rtnl_dereference(*fp))
if (pfp == f)
break;
RCU_INIT_POINTER(fnew->next, rtnl_dereference(pfp->next));
rcu_assign_pointer(*fp, fnew);
tcf_unbind_filter(tp, &f->res);
tcf_exts_get_net(&f->exts);
tcf_queue_work(&f->rwork, fw_delete_filter_work);
*arg = fnew;
return err;
}
if (!handle)
return -EINVAL;
if (!head) {
u32 mask = 0xFFFFFFFF;
if (tb[TCA_FW_MASK])
mask = nla_get_u32(tb[TCA_FW_MASK]);
head = kzalloc(sizeof(*head), GFP_KERNEL);
if (!head)
return -ENOBUFS;
head->mask = mask;
rcu_assign_pointer(tp->root, head);
}
f = kzalloc(sizeof(struct fw_filter), GFP_KERNEL);
if (f == NULL)
return -ENOBUFS;
err = tcf_exts_init(&f->exts, net, TCA_FW_ACT, TCA_FW_POLICE);
if (err < 0)
goto errout;
f->id = handle;
f->tp = tp;
err = fw_set_parms(net, tp, f, tb, tca, base, ovr, extack);
if (err < 0)
goto errout;
RCU_INIT_POINTER(f->next, head->ht[fw_hash(handle)]);
rcu_assign_pointer(head->ht[fw_hash(handle)], f);
*arg = f;
return 0;
errout:
tcf_exts_destroy(&f->exts);
kfree(f);
return err;
}
static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg,
bool rtnl_held)
{
struct fw_head *head = rtnl_dereference(tp->root);
int h;
if (head == NULL)
arg->stop = 1;
if (arg->stop)
return;
for (h = 0; h < HTSIZE; h++) {
struct fw_filter *f;
for (f = rtnl_dereference(head->ht[h]); f;
f = rtnl_dereference(f->next)) {
if (arg->count < arg->skip) {
arg->count++;
continue;
}
if (arg->fn(tp, f, arg) < 0) {
arg->stop = 1;
return;
}
arg->count++;
}
}
}
static int fw_dump(struct net *net, struct tcf_proto *tp, void *fh,
struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
{
struct fw_head *head = rtnl_dereference(tp->root);
struct fw_filter *f = fh;
struct nlattr *nest;
if (f == NULL)
return skb->len;
t->tcm_handle = f->id;
if (!f->res.classid && !tcf_exts_has_actions(&f->exts))
return skb->len;
nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
if (nest == NULL)
goto nla_put_failure;
if (f->res.classid &&
nla_put_u32(skb, TCA_FW_CLASSID, f->res.classid))
goto nla_put_failure;
if (f->ifindex) {
struct net_device *dev;
dev = __dev_get_by_index(net, f->ifindex);
if (dev && nla_put_string(skb, TCA_FW_INDEV, dev->name))
goto nla_put_failure;
}
if (head->mask != 0xFFFFFFFF &&
nla_put_u32(skb, TCA_FW_MASK, head->mask))
goto nla_put_failure;
if (tcf_exts_dump(skb, &f->exts) < 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 void fw_bind_class(void *fh, u32 classid, unsigned long cl)
{
struct fw_filter *f = fh;
if (f && f->res.classid == classid)
f->res.class = cl;
}
static struct tcf_proto_ops cls_fw_ops __read_mostly = {
.kind = "fw",
.classify = fw_classify,
.init = fw_init,
.destroy = fw_destroy,
.get = fw_get,
.change = fw_change,
.delete = fw_delete,
.walk = fw_walk,
.dump = fw_dump,
.bind_class = fw_bind_class,
.owner = THIS_MODULE,
};
static int __init init_fw(void)
{
return register_tcf_proto_ops(&cls_fw_ops);
}
static void __exit exit_fw(void)
{
unregister_tcf_proto_ops(&cls_fw_ops);
}
module_init(init_fw)
module_exit(exit_fw)
MODULE_LICENSE("GPL");