linux/net/sched/act_api.c
WANG Cong 22dc13c837 net_sched: convert tcf_exts from list to pointer array
As pointed out by Jamal, an action could be shared by
multiple filters, so we can't use list to chain them
any more after we get rid of the original tc_action.
Instead, we could just save pointers to these actions
in tcf_exts, since they are refcount'ed, so convert
the list to an array of pointers.

The "ugly" part is the action API still accepts list
as a parameter, I just introduce a helper function to
convert the array of pointers to a list, instead of
relying on the C99 feature to iterate the array.

Fixes: a85a970af2 ("net_sched: move tc_action into tcf_common")
Reported-by: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-17 19:27:51 -04:00

1086 lines
23 KiB
C

/*
* net/sched/act_api.c Packet action API.
*
* 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.
*
* Author: Jamal Hadi Salim
*
*
*/
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/skbuff.h>
#include <linux/init.h>
#include <linux/kmod.h>
#include <linux/err.h>
#include <linux/module.h>
#include <net/net_namespace.h>
#include <net/sock.h>
#include <net/sch_generic.h>
#include <net/act_api.h>
#include <net/netlink.h>
static void free_tcf(struct rcu_head *head)
{
struct tc_action *p = container_of(head, struct tc_action, tcfa_rcu);
free_percpu(p->cpu_bstats);
free_percpu(p->cpu_qstats);
kfree(p);
}
static void tcf_hash_destroy(struct tcf_hashinfo *hinfo, struct tc_action *p)
{
spin_lock_bh(&hinfo->lock);
hlist_del(&p->tcfa_head);
spin_unlock_bh(&hinfo->lock);
gen_kill_estimator(&p->tcfa_bstats,
&p->tcfa_rate_est);
/*
* gen_estimator est_timer() might access p->tcfa_lock
* or bstats, wait a RCU grace period before freeing p
*/
call_rcu(&p->tcfa_rcu, free_tcf);
}
int __tcf_hash_release(struct tc_action *p, bool bind, bool strict)
{
int ret = 0;
if (p) {
if (bind)
p->tcfa_bindcnt--;
else if (strict && p->tcfa_bindcnt > 0)
return -EPERM;
p->tcfa_refcnt--;
if (p->tcfa_bindcnt <= 0 && p->tcfa_refcnt <= 0) {
if (p->ops->cleanup)
p->ops->cleanup(p, bind);
tcf_hash_destroy(p->hinfo, p);
ret = ACT_P_DELETED;
}
}
return ret;
}
EXPORT_SYMBOL(__tcf_hash_release);
static int tcf_dump_walker(struct tcf_hashinfo *hinfo, struct sk_buff *skb,
struct netlink_callback *cb)
{
int err = 0, index = -1, i = 0, s_i = 0, n_i = 0;
struct nlattr *nest;
spin_lock_bh(&hinfo->lock);
s_i = cb->args[0];
for (i = 0; i < (hinfo->hmask + 1); i++) {
struct hlist_head *head;
struct tc_action *p;
head = &hinfo->htab[tcf_hash(i, hinfo->hmask)];
hlist_for_each_entry_rcu(p, head, tcfa_head) {
index++;
if (index < s_i)
continue;
nest = nla_nest_start(skb, n_i);
if (nest == NULL)
goto nla_put_failure;
err = tcf_action_dump_1(skb, p, 0, 0);
if (err < 0) {
index--;
nlmsg_trim(skb, nest);
goto done;
}
nla_nest_end(skb, nest);
n_i++;
if (n_i >= TCA_ACT_MAX_PRIO)
goto done;
}
}
done:
spin_unlock_bh(&hinfo->lock);
if (n_i)
cb->args[0] += n_i;
return n_i;
nla_put_failure:
nla_nest_cancel(skb, nest);
goto done;
}
static int tcf_del_walker(struct tcf_hashinfo *hinfo, struct sk_buff *skb,
const struct tc_action_ops *ops)
{
struct nlattr *nest;
int i = 0, n_i = 0;
int ret = -EINVAL;
nest = nla_nest_start(skb, 0);
if (nest == NULL)
goto nla_put_failure;
if (nla_put_string(skb, TCA_KIND, ops->kind))
goto nla_put_failure;
for (i = 0; i < (hinfo->hmask + 1); i++) {
struct hlist_head *head;
struct hlist_node *n;
struct tc_action *p;
head = &hinfo->htab[tcf_hash(i, hinfo->hmask)];
hlist_for_each_entry_safe(p, n, head, tcfa_head) {
ret = __tcf_hash_release(p, false, true);
if (ret == ACT_P_DELETED) {
module_put(p->ops->owner);
n_i++;
} else if (ret < 0)
goto nla_put_failure;
}
}
if (nla_put_u32(skb, TCA_FCNT, n_i))
goto nla_put_failure;
nla_nest_end(skb, nest);
return n_i;
nla_put_failure:
nla_nest_cancel(skb, nest);
return ret;
}
int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
struct netlink_callback *cb, int type,
const struct tc_action_ops *ops)
{
struct tcf_hashinfo *hinfo = tn->hinfo;
if (type == RTM_DELACTION) {
return tcf_del_walker(hinfo, skb, ops);
} else if (type == RTM_GETACTION) {
return tcf_dump_walker(hinfo, skb, cb);
} else {
WARN(1, "tcf_generic_walker: unknown action %d\n", type);
return -EINVAL;
}
}
EXPORT_SYMBOL(tcf_generic_walker);
static struct tc_action *tcf_hash_lookup(u32 index, struct tcf_hashinfo *hinfo)
{
struct tc_action *p = NULL;
struct hlist_head *head;
spin_lock_bh(&hinfo->lock);
head = &hinfo->htab[tcf_hash(index, hinfo->hmask)];
hlist_for_each_entry_rcu(p, head, tcfa_head)
if (p->tcfa_index == index)
break;
spin_unlock_bh(&hinfo->lock);
return p;
}
u32 tcf_hash_new_index(struct tc_action_net *tn)
{
struct tcf_hashinfo *hinfo = tn->hinfo;
u32 val = hinfo->index;
do {
if (++val == 0)
val = 1;
} while (tcf_hash_lookup(val, hinfo));
hinfo->index = val;
return val;
}
EXPORT_SYMBOL(tcf_hash_new_index);
int tcf_hash_search(struct tc_action_net *tn, struct tc_action **a, u32 index)
{
struct tcf_hashinfo *hinfo = tn->hinfo;
struct tc_action *p = tcf_hash_lookup(index, hinfo);
if (p) {
*a = p;
return 1;
}
return 0;
}
EXPORT_SYMBOL(tcf_hash_search);
bool tcf_hash_check(struct tc_action_net *tn, u32 index, struct tc_action **a,
int bind)
{
struct tcf_hashinfo *hinfo = tn->hinfo;
struct tc_action *p = NULL;
if (index && (p = tcf_hash_lookup(index, hinfo)) != NULL) {
if (bind)
p->tcfa_bindcnt++;
p->tcfa_refcnt++;
*a = p;
return true;
}
return false;
}
EXPORT_SYMBOL(tcf_hash_check);
void tcf_hash_cleanup(struct tc_action *a, struct nlattr *est)
{
if (est)
gen_kill_estimator(&a->tcfa_bstats,
&a->tcfa_rate_est);
call_rcu(&a->tcfa_rcu, free_tcf);
}
EXPORT_SYMBOL(tcf_hash_cleanup);
int tcf_hash_create(struct tc_action_net *tn, u32 index, struct nlattr *est,
struct tc_action **a, const struct tc_action_ops *ops,
int bind, bool cpustats)
{
struct tc_action *p = kzalloc(ops->size, GFP_KERNEL);
struct tcf_hashinfo *hinfo = tn->hinfo;
int err = -ENOMEM;
if (unlikely(!p))
return -ENOMEM;
p->tcfa_refcnt = 1;
if (bind)
p->tcfa_bindcnt = 1;
if (cpustats) {
p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
if (!p->cpu_bstats) {
err1:
kfree(p);
return err;
}
p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
if (!p->cpu_qstats) {
err2:
free_percpu(p->cpu_bstats);
goto err1;
}
}
spin_lock_init(&p->tcfa_lock);
INIT_HLIST_NODE(&p->tcfa_head);
p->tcfa_index = index ? index : tcf_hash_new_index(tn);
p->tcfa_tm.install = jiffies;
p->tcfa_tm.lastuse = jiffies;
p->tcfa_tm.firstuse = 0;
if (est) {
err = gen_new_estimator(&p->tcfa_bstats, p->cpu_bstats,
&p->tcfa_rate_est,
&p->tcfa_lock, NULL, est);
if (err) {
free_percpu(p->cpu_qstats);
goto err2;
}
}
p->hinfo = hinfo;
p->ops = ops;
INIT_LIST_HEAD(&p->list);
*a = p;
return 0;
}
EXPORT_SYMBOL(tcf_hash_create);
void tcf_hash_insert(struct tc_action_net *tn, struct tc_action *a)
{
struct tcf_hashinfo *hinfo = tn->hinfo;
unsigned int h = tcf_hash(a->tcfa_index, hinfo->hmask);
spin_lock_bh(&hinfo->lock);
hlist_add_head(&a->tcfa_head, &hinfo->htab[h]);
spin_unlock_bh(&hinfo->lock);
}
EXPORT_SYMBOL(tcf_hash_insert);
void tcf_hashinfo_destroy(const struct tc_action_ops *ops,
struct tcf_hashinfo *hinfo)
{
int i;
for (i = 0; i < hinfo->hmask + 1; i++) {
struct tc_action *p;
struct hlist_node *n;
hlist_for_each_entry_safe(p, n, &hinfo->htab[i], tcfa_head) {
int ret;
ret = __tcf_hash_release(p, false, true);
if (ret == ACT_P_DELETED)
module_put(ops->owner);
else if (ret < 0)
return;
}
}
kfree(hinfo->htab);
}
EXPORT_SYMBOL(tcf_hashinfo_destroy);
static LIST_HEAD(act_base);
static DEFINE_RWLOCK(act_mod_lock);
int tcf_register_action(struct tc_action_ops *act,
struct pernet_operations *ops)
{
struct tc_action_ops *a;
int ret;
if (!act->act || !act->dump || !act->init || !act->walk || !act->lookup)
return -EINVAL;
write_lock(&act_mod_lock);
list_for_each_entry(a, &act_base, head) {
if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) {
write_unlock(&act_mod_lock);
return -EEXIST;
}
}
list_add_tail(&act->head, &act_base);
write_unlock(&act_mod_lock);
ret = register_pernet_subsys(ops);
if (ret) {
tcf_unregister_action(act, ops);
return ret;
}
return 0;
}
EXPORT_SYMBOL(tcf_register_action);
int tcf_unregister_action(struct tc_action_ops *act,
struct pernet_operations *ops)
{
struct tc_action_ops *a;
int err = -ENOENT;
unregister_pernet_subsys(ops);
write_lock(&act_mod_lock);
list_for_each_entry(a, &act_base, head) {
if (a == act) {
list_del(&act->head);
err = 0;
break;
}
}
write_unlock(&act_mod_lock);
return err;
}
EXPORT_SYMBOL(tcf_unregister_action);
/* lookup by name */
static struct tc_action_ops *tc_lookup_action_n(char *kind)
{
struct tc_action_ops *a, *res = NULL;
if (kind) {
read_lock(&act_mod_lock);
list_for_each_entry(a, &act_base, head) {
if (strcmp(kind, a->kind) == 0) {
if (try_module_get(a->owner))
res = a;
break;
}
}
read_unlock(&act_mod_lock);
}
return res;
}
/* lookup by nlattr */
static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
{
struct tc_action_ops *a, *res = NULL;
if (kind) {
read_lock(&act_mod_lock);
list_for_each_entry(a, &act_base, head) {
if (nla_strcmp(kind, a->kind) == 0) {
if (try_module_get(a->owner))
res = a;
break;
}
}
read_unlock(&act_mod_lock);
}
return res;
}
int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
int nr_actions, struct tcf_result *res)
{
int ret = -1, i;
if (skb->tc_verd & TC_NCLS) {
skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
ret = TC_ACT_OK;
goto exec_done;
}
for (i = 0; i < nr_actions; i++) {
const struct tc_action *a = actions[i];
repeat:
ret = a->ops->act(skb, a, res);
if (ret == TC_ACT_REPEAT)
goto repeat; /* we need a ttl - JHS */
if (ret != TC_ACT_PIPE)
goto exec_done;
}
exec_done:
return ret;
}
EXPORT_SYMBOL(tcf_action_exec);
int tcf_action_destroy(struct list_head *actions, int bind)
{
struct tc_action *a, *tmp;
int ret = 0;
list_for_each_entry_safe(a, tmp, actions, list) {
ret = __tcf_hash_release(a, bind, true);
if (ret == ACT_P_DELETED)
module_put(a->ops->owner);
else if (ret < 0)
return ret;
}
return ret;
}
int
tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
{
return a->ops->dump(skb, a, bind, ref);
}
int
tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
{
int err = -EINVAL;
unsigned char *b = skb_tail_pointer(skb);
struct nlattr *nest;
if (nla_put_string(skb, TCA_KIND, a->ops->kind))
goto nla_put_failure;
if (tcf_action_copy_stats(skb, a, 0))
goto nla_put_failure;
nest = nla_nest_start(skb, TCA_OPTIONS);
if (nest == NULL)
goto nla_put_failure;
err = tcf_action_dump_old(skb, a, bind, ref);
if (err > 0) {
nla_nest_end(skb, nest);
return err;
}
nla_put_failure:
nlmsg_trim(skb, b);
return -1;
}
EXPORT_SYMBOL(tcf_action_dump_1);
int tcf_action_dump(struct sk_buff *skb, struct list_head *actions,
int bind, int ref)
{
struct tc_action *a;
int err = -EINVAL;
struct nlattr *nest;
list_for_each_entry(a, actions, list) {
nest = nla_nest_start(skb, a->order);
if (nest == NULL)
goto nla_put_failure;
err = tcf_action_dump_1(skb, a, bind, ref);
if (err < 0)
goto errout;
nla_nest_end(skb, nest);
}
return 0;
nla_put_failure:
err = -EINVAL;
errout:
nla_nest_cancel(skb, nest);
return err;
}
struct tc_action *tcf_action_init_1(struct net *net, struct nlattr *nla,
struct nlattr *est, char *name, int ovr,
int bind)
{
struct tc_action *a;
struct tc_action_ops *a_o;
char act_name[IFNAMSIZ];
struct nlattr *tb[TCA_ACT_MAX + 1];
struct nlattr *kind;
int err;
if (name == NULL) {
err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
if (err < 0)
goto err_out;
err = -EINVAL;
kind = tb[TCA_ACT_KIND];
if (kind == NULL)
goto err_out;
if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ)
goto err_out;
} else {
err = -EINVAL;
if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ)
goto err_out;
}
a_o = tc_lookup_action_n(act_name);
if (a_o == NULL) {
#ifdef CONFIG_MODULES
rtnl_unlock();
request_module("act_%s", act_name);
rtnl_lock();
a_o = tc_lookup_action_n(act_name);
/* We dropped the RTNL semaphore in order to
* perform the module load. So, even if we
* succeeded in loading the module we have to
* tell the caller to replay the request. We
* indicate this using -EAGAIN.
*/
if (a_o != NULL) {
err = -EAGAIN;
goto err_mod;
}
#endif
err = -ENOENT;
goto err_out;
}
/* backward compatibility for policer */
if (name == NULL)
err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, ovr, bind);
else
err = a_o->init(net, nla, est, &a, ovr, bind);
if (err < 0)
goto err_mod;
/* module count goes up only when brand new policy is created
* if it exists and is only bound to in a_o->init() then
* ACT_P_CREATED is not returned (a zero is).
*/
if (err != ACT_P_CREATED)
module_put(a_o->owner);
return a;
err_mod:
module_put(a_o->owner);
err_out:
return ERR_PTR(err);
}
int tcf_action_init(struct net *net, struct nlattr *nla,
struct nlattr *est, char *name, int ovr,
int bind, struct list_head *actions)
{
struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
struct tc_action *act;
int err;
int i;
err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
if (err < 0)
return err;
for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
act = tcf_action_init_1(net, tb[i], est, name, ovr, bind);
if (IS_ERR(act)) {
err = PTR_ERR(act);
goto err;
}
act->order = i;
list_add_tail(&act->list, actions);
}
return 0;
err:
tcf_action_destroy(actions, bind);
return err;
}
int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
int compat_mode)
{
int err = 0;
struct gnet_dump d;
if (p == NULL)
goto errout;
/* compat_mode being true specifies a call that is supposed
* to add additional backward compatibility statistic TLVs.
*/
if (compat_mode) {
if (p->type == TCA_OLD_COMPAT)
err = gnet_stats_start_copy_compat(skb, 0,
TCA_STATS,
TCA_XSTATS,
&p->tcfa_lock, &d,
TCA_PAD);
else
return 0;
} else
err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
&p->tcfa_lock, &d, TCA_ACT_PAD);
if (err < 0)
goto errout;
if (gnet_stats_copy_basic(NULL, &d, p->cpu_bstats, &p->tcfa_bstats) < 0 ||
gnet_stats_copy_rate_est(&d, &p->tcfa_bstats,
&p->tcfa_rate_est) < 0 ||
gnet_stats_copy_queue(&d, p->cpu_qstats,
&p->tcfa_qstats,
p->tcfa_qstats.qlen) < 0)
goto errout;
if (gnet_stats_finish_copy(&d) < 0)
goto errout;
return 0;
errout:
return -1;
}
static int tca_get_fill(struct sk_buff *skb, struct list_head *actions,
u32 portid, u32 seq, u16 flags, int event, int bind,
int ref)
{
struct tcamsg *t;
struct nlmsghdr *nlh;
unsigned char *b = skb_tail_pointer(skb);
struct nlattr *nest;
nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
if (!nlh)
goto out_nlmsg_trim;
t = nlmsg_data(nlh);
t->tca_family = AF_UNSPEC;
t->tca__pad1 = 0;
t->tca__pad2 = 0;
nest = nla_nest_start(skb, TCA_ACT_TAB);
if (nest == NULL)
goto out_nlmsg_trim;
if (tcf_action_dump(skb, actions, bind, ref) < 0)
goto out_nlmsg_trim;
nla_nest_end(skb, nest);
nlh->nlmsg_len = skb_tail_pointer(skb) - b;
return skb->len;
out_nlmsg_trim:
nlmsg_trim(skb, b);
return -1;
}
static int
act_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
struct list_head *actions, int event)
{
struct sk_buff *skb;
skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (!skb)
return -ENOBUFS;
if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
0, 0) <= 0) {
kfree_skb(skb);
return -EINVAL;
}
return rtnl_unicast(skb, net, portid);
}
static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
struct nlmsghdr *n, u32 portid)
{
struct nlattr *tb[TCA_ACT_MAX + 1];
const struct tc_action_ops *ops;
struct tc_action *a;
int index;
int err;
err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
if (err < 0)
goto err_out;
err = -EINVAL;
if (tb[TCA_ACT_INDEX] == NULL ||
nla_len(tb[TCA_ACT_INDEX]) < sizeof(index))
goto err_out;
index = nla_get_u32(tb[TCA_ACT_INDEX]);
err = -EINVAL;
ops = tc_lookup_action(tb[TCA_ACT_KIND]);
if (!ops) /* could happen in batch of actions */
goto err_out;
err = -ENOENT;
if (ops->lookup(net, &a, index) == 0)
goto err_mod;
module_put(ops->owner);
return a;
err_mod:
module_put(ops->owner);
err_out:
return ERR_PTR(err);
}
static int tca_action_flush(struct net *net, struct nlattr *nla,
struct nlmsghdr *n, u32 portid)
{
struct sk_buff *skb;
unsigned char *b;
struct nlmsghdr *nlh;
struct tcamsg *t;
struct netlink_callback dcb;
struct nlattr *nest;
struct nlattr *tb[TCA_ACT_MAX + 1];
const struct tc_action_ops *ops;
struct nlattr *kind;
int err = -ENOMEM;
skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (!skb) {
pr_debug("tca_action_flush: failed skb alloc\n");
return err;
}
b = skb_tail_pointer(skb);
err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
if (err < 0)
goto err_out;
err = -EINVAL;
kind = tb[TCA_ACT_KIND];
ops = tc_lookup_action(kind);
if (!ops) /*some idjot trying to flush unknown action */
goto err_out;
nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
sizeof(*t), 0);
if (!nlh)
goto out_module_put;
t = nlmsg_data(nlh);
t->tca_family = AF_UNSPEC;
t->tca__pad1 = 0;
t->tca__pad2 = 0;
nest = nla_nest_start(skb, TCA_ACT_TAB);
if (nest == NULL)
goto out_module_put;
err = ops->walk(net, skb, &dcb, RTM_DELACTION, ops);
if (err < 0)
goto out_module_put;
if (err == 0)
goto noflush_out;
nla_nest_end(skb, nest);
nlh->nlmsg_len = skb_tail_pointer(skb) - b;
nlh->nlmsg_flags |= NLM_F_ROOT;
module_put(ops->owner);
err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
n->nlmsg_flags & NLM_F_ECHO);
if (err > 0)
return 0;
return err;
out_module_put:
module_put(ops->owner);
err_out:
noflush_out:
kfree_skb(skb);
return err;
}
static int
tcf_del_notify(struct net *net, struct nlmsghdr *n, struct list_head *actions,
u32 portid)
{
int ret;
struct sk_buff *skb;
skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (!skb)
return -ENOBUFS;
if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
0, 1) <= 0) {
kfree_skb(skb);
return -EINVAL;
}
/* now do the delete */
ret = tcf_action_destroy(actions, 0);
if (ret < 0) {
kfree_skb(skb);
return ret;
}
ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
n->nlmsg_flags & NLM_F_ECHO);
if (ret > 0)
return 0;
return ret;
}
static int
tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
u32 portid, int event)
{
int i, ret;
struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
struct tc_action *act;
LIST_HEAD(actions);
ret = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
if (ret < 0)
return ret;
if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
if (tb[1] != NULL)
return tca_action_flush(net, tb[1], n, portid);
else
return -EINVAL;
}
for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
act = tcf_action_get_1(net, tb[i], n, portid);
if (IS_ERR(act)) {
ret = PTR_ERR(act);
goto err;
}
act->order = i;
list_add_tail(&act->list, &actions);
}
if (event == RTM_GETACTION)
ret = act_get_notify(net, portid, n, &actions, event);
else { /* delete */
ret = tcf_del_notify(net, n, &actions, portid);
if (ret)
goto err;
return ret;
}
err:
tcf_action_destroy(&actions, 0);
return ret;
}
static int
tcf_add_notify(struct net *net, struct nlmsghdr *n, struct list_head *actions,
u32 portid)
{
struct sk_buff *skb;
int err = 0;
skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (!skb)
return -ENOBUFS;
if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
RTM_NEWACTION, 0, 0) <= 0) {
kfree_skb(skb);
return -EINVAL;
}
err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
n->nlmsg_flags & NLM_F_ECHO);
if (err > 0)
err = 0;
return err;
}
static int
tcf_action_add(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
u32 portid, int ovr)
{
int ret = 0;
LIST_HEAD(actions);
ret = tcf_action_init(net, nla, NULL, NULL, ovr, 0, &actions);
if (ret)
return ret;
return tcf_add_notify(net, n, &actions, portid);
}
static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n)
{
struct net *net = sock_net(skb->sk);
struct nlattr *tca[TCA_ACT_MAX + 1];
u32 portid = skb ? NETLINK_CB(skb).portid : 0;
int ret = 0, ovr = 0;
if ((n->nlmsg_type != RTM_GETACTION) &&
!netlink_capable(skb, CAP_NET_ADMIN))
return -EPERM;
ret = nlmsg_parse(n, sizeof(struct tcamsg), tca, TCA_ACT_MAX, NULL);
if (ret < 0)
return ret;
if (tca[TCA_ACT_TAB] == NULL) {
pr_notice("tc_ctl_action: received NO action attribs\n");
return -EINVAL;
}
/* n->nlmsg_flags & NLM_F_CREATE */
switch (n->nlmsg_type) {
case RTM_NEWACTION:
/* we are going to assume all other flags
* imply create only if it doesn't exist
* Note that CREATE | EXCL implies that
* but since we want avoid ambiguity (eg when flags
* is zero) then just set this
*/
if (n->nlmsg_flags & NLM_F_REPLACE)
ovr = 1;
replay:
ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, ovr);
if (ret == -EAGAIN)
goto replay;
break;
case RTM_DELACTION:
ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
portid, RTM_DELACTION);
break;
case RTM_GETACTION:
ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
portid, RTM_GETACTION);
break;
default:
BUG();
}
return ret;
}
static struct nlattr *
find_dump_kind(const struct nlmsghdr *n)
{
struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
struct nlattr *nla[TCAA_MAX + 1];
struct nlattr *kind;
if (nlmsg_parse(n, sizeof(struct tcamsg), nla, TCAA_MAX, NULL) < 0)
return NULL;
tb1 = nla[TCA_ACT_TAB];
if (tb1 == NULL)
return NULL;
if (nla_parse(tb, TCA_ACT_MAX_PRIO, nla_data(tb1),
NLMSG_ALIGN(nla_len(tb1)), NULL) < 0)
return NULL;
if (tb[1] == NULL)
return NULL;
if (nla_parse(tb2, TCA_ACT_MAX, nla_data(tb[1]),
nla_len(tb[1]), NULL) < 0)
return NULL;
kind = tb2[TCA_ACT_KIND];
return kind;
}
static int
tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
{
struct net *net = sock_net(skb->sk);
struct nlmsghdr *nlh;
unsigned char *b = skb_tail_pointer(skb);
struct nlattr *nest;
struct tc_action_ops *a_o;
int ret = 0;
struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
struct nlattr *kind = find_dump_kind(cb->nlh);
if (kind == NULL) {
pr_info("tc_dump_action: action bad kind\n");
return 0;
}
a_o = tc_lookup_action(kind);
if (a_o == NULL)
return 0;
nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
cb->nlh->nlmsg_type, sizeof(*t), 0);
if (!nlh)
goto out_module_put;
t = nlmsg_data(nlh);
t->tca_family = AF_UNSPEC;
t->tca__pad1 = 0;
t->tca__pad2 = 0;
nest = nla_nest_start(skb, TCA_ACT_TAB);
if (nest == NULL)
goto out_module_put;
ret = a_o->walk(net, skb, cb, RTM_GETACTION, a_o);
if (ret < 0)
goto out_module_put;
if (ret > 0) {
nla_nest_end(skb, nest);
ret = skb->len;
} else
nlmsg_trim(skb, b);
nlh->nlmsg_len = skb_tail_pointer(skb) - b;
if (NETLINK_CB(cb->skb).portid && ret)
nlh->nlmsg_flags |= NLM_F_MULTI;
module_put(a_o->owner);
return skb->len;
out_module_put:
module_put(a_o->owner);
nlmsg_trim(skb, b);
return skb->len;
}
static int __init tc_action_init(void)
{
rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, NULL);
rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, NULL);
rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
NULL);
return 0;
}
subsys_initcall(tc_action_init);