linux-stable/net/sched/act_api.c
Benjamin LaHaise c1b52739e4 pkt_sched: namespace aware act_mirred
Eric Dumazet pointed out that act_mirred needs to find the current net_ns,
and struct net pointer is not provided in the call chain.  His original
patch made use of current->nsproxy->net_ns to find the network namespace,
but this fails to work correctly for userspace code that makes use of
netlink sockets in different network namespaces.  Instead, pass the
"struct net *" down along the call chain to where it is needed.

This version removes the ifb changes as Eric has submitted that patch
separately, but is otherwise identical to the previous version.

Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Tested-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-14 15:09:36 -05:00

1138 lines
24 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>
void tcf_hash_destroy(struct tcf_common *p, struct tcf_hashinfo *hinfo)
{
unsigned int h = tcf_hash(p->tcfc_index, hinfo->hmask);
struct tcf_common **p1p;
for (p1p = &hinfo->htab[h]; *p1p; p1p = &(*p1p)->tcfc_next) {
if (*p1p == p) {
write_lock_bh(hinfo->lock);
*p1p = p->tcfc_next;
write_unlock_bh(hinfo->lock);
gen_kill_estimator(&p->tcfc_bstats,
&p->tcfc_rate_est);
/*
* gen_estimator est_timer() might access p->tcfc_lock
* or bstats, wait a RCU grace period before freeing p
*/
kfree_rcu(p, tcfc_rcu);
return;
}
}
WARN_ON(1);
}
EXPORT_SYMBOL(tcf_hash_destroy);
int tcf_hash_release(struct tcf_common *p, int bind,
struct tcf_hashinfo *hinfo)
{
int ret = 0;
if (p) {
if (bind)
p->tcfc_bindcnt--;
p->tcfc_refcnt--;
if (p->tcfc_bindcnt <= 0 && p->tcfc_refcnt <= 0) {
tcf_hash_destroy(p, hinfo);
ret = 1;
}
}
return ret;
}
EXPORT_SYMBOL(tcf_hash_release);
static int tcf_dump_walker(struct sk_buff *skb, struct netlink_callback *cb,
struct tc_action *a, struct tcf_hashinfo *hinfo)
{
struct tcf_common *p;
int err = 0, index = -1, i = 0, s_i = 0, n_i = 0;
struct nlattr *nest;
read_lock_bh(hinfo->lock);
s_i = cb->args[0];
for (i = 0; i < (hinfo->hmask + 1); i++) {
p = hinfo->htab[tcf_hash(i, hinfo->hmask)];
for (; p; p = p->tcfc_next) {
index++;
if (index < s_i)
continue;
a->priv = p;
a->order = n_i;
nest = nla_nest_start(skb, a->order);
if (nest == NULL)
goto nla_put_failure;
err = tcf_action_dump_1(skb, a, 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:
read_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 sk_buff *skb, struct tc_action *a,
struct tcf_hashinfo *hinfo)
{
struct tcf_common *p, *s_p;
struct nlattr *nest;
int i = 0, n_i = 0;
nest = nla_nest_start(skb, a->order);
if (nest == NULL)
goto nla_put_failure;
if (nla_put_string(skb, TCA_KIND, a->ops->kind))
goto nla_put_failure;
for (i = 0; i < (hinfo->hmask + 1); i++) {
p = hinfo->htab[tcf_hash(i, hinfo->hmask)];
while (p != NULL) {
s_p = p->tcfc_next;
if (ACT_P_DELETED == tcf_hash_release(p, 0, hinfo))
module_put(a->ops->owner);
n_i++;
p = s_p;
}
}
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 -EINVAL;
}
int tcf_generic_walker(struct sk_buff *skb, struct netlink_callback *cb,
int type, struct tc_action *a)
{
struct tcf_hashinfo *hinfo = a->ops->hinfo;
if (type == RTM_DELACTION) {
return tcf_del_walker(skb, a, hinfo);
} else if (type == RTM_GETACTION) {
return tcf_dump_walker(skb, cb, a, hinfo);
} else {
WARN(1, "tcf_generic_walker: unknown action %d\n", type);
return -EINVAL;
}
}
EXPORT_SYMBOL(tcf_generic_walker);
struct tcf_common *tcf_hash_lookup(u32 index, struct tcf_hashinfo *hinfo)
{
struct tcf_common *p;
read_lock_bh(hinfo->lock);
for (p = hinfo->htab[tcf_hash(index, hinfo->hmask)]; p;
p = p->tcfc_next) {
if (p->tcfc_index == index)
break;
}
read_unlock_bh(hinfo->lock);
return p;
}
EXPORT_SYMBOL(tcf_hash_lookup);
u32 tcf_hash_new_index(u32 *idx_gen, struct tcf_hashinfo *hinfo)
{
u32 val = *idx_gen;
do {
if (++val == 0)
val = 1;
} while (tcf_hash_lookup(val, hinfo));
return (*idx_gen = val);
}
EXPORT_SYMBOL(tcf_hash_new_index);
int tcf_hash_search(struct tc_action *a, u32 index)
{
struct tcf_hashinfo *hinfo = a->ops->hinfo;
struct tcf_common *p = tcf_hash_lookup(index, hinfo);
if (p) {
a->priv = p;
return 1;
}
return 0;
}
EXPORT_SYMBOL(tcf_hash_search);
struct tcf_common *tcf_hash_check(u32 index, struct tc_action *a, int bind,
struct tcf_hashinfo *hinfo)
{
struct tcf_common *p = NULL;
if (index && (p = tcf_hash_lookup(index, hinfo)) != NULL) {
if (bind)
p->tcfc_bindcnt++;
p->tcfc_refcnt++;
a->priv = p;
}
return p;
}
EXPORT_SYMBOL(tcf_hash_check);
struct tcf_common *tcf_hash_create(u32 index, struct nlattr *est,
struct tc_action *a, int size, int bind,
u32 *idx_gen, struct tcf_hashinfo *hinfo)
{
struct tcf_common *p = kzalloc(size, GFP_KERNEL);
if (unlikely(!p))
return ERR_PTR(-ENOMEM);
p->tcfc_refcnt = 1;
if (bind)
p->tcfc_bindcnt = 1;
spin_lock_init(&p->tcfc_lock);
p->tcfc_index = index ? index : tcf_hash_new_index(idx_gen, hinfo);
p->tcfc_tm.install = jiffies;
p->tcfc_tm.lastuse = jiffies;
if (est) {
int err = gen_new_estimator(&p->tcfc_bstats, &p->tcfc_rate_est,
&p->tcfc_lock, est);
if (err) {
kfree(p);
return ERR_PTR(err);
}
}
a->priv = (void *) p;
return p;
}
EXPORT_SYMBOL(tcf_hash_create);
void tcf_hash_insert(struct tcf_common *p, struct tcf_hashinfo *hinfo)
{
unsigned int h = tcf_hash(p->tcfc_index, hinfo->hmask);
write_lock_bh(hinfo->lock);
p->tcfc_next = hinfo->htab[h];
hinfo->htab[h] = p;
write_unlock_bh(hinfo->lock);
}
EXPORT_SYMBOL(tcf_hash_insert);
static struct tc_action_ops *act_base = NULL;
static DEFINE_RWLOCK(act_mod_lock);
int tcf_register_action(struct tc_action_ops *act)
{
struct tc_action_ops *a, **ap;
write_lock(&act_mod_lock);
for (ap = &act_base; (a = *ap) != NULL; ap = &a->next) {
if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) {
write_unlock(&act_mod_lock);
return -EEXIST;
}
}
act->next = NULL;
*ap = act;
write_unlock(&act_mod_lock);
return 0;
}
EXPORT_SYMBOL(tcf_register_action);
int tcf_unregister_action(struct tc_action_ops *act)
{
struct tc_action_ops *a, **ap;
int err = -ENOENT;
write_lock(&act_mod_lock);
for (ap = &act_base; (a = *ap) != NULL; ap = &a->next)
if (a == act)
break;
if (a) {
*ap = a->next;
a->next = NULL;
err = 0;
}
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 = NULL;
if (kind) {
read_lock(&act_mod_lock);
for (a = act_base; a; a = a->next) {
if (strcmp(kind, a->kind) == 0) {
if (!try_module_get(a->owner)) {
read_unlock(&act_mod_lock);
return NULL;
}
break;
}
}
read_unlock(&act_mod_lock);
}
return a;
}
/* lookup by nlattr */
static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
{
struct tc_action_ops *a = NULL;
if (kind) {
read_lock(&act_mod_lock);
for (a = act_base; a; a = a->next) {
if (nla_strcmp(kind, a->kind) == 0) {
if (!try_module_get(a->owner)) {
read_unlock(&act_mod_lock);
return NULL;
}
break;
}
}
read_unlock(&act_mod_lock);
}
return a;
}
#if 0
/* lookup by id */
static struct tc_action_ops *tc_lookup_action_id(u32 type)
{
struct tc_action_ops *a = NULL;
if (type) {
read_lock(&act_mod_lock);
for (a = act_base; a; a = a->next) {
if (a->type == type) {
if (!try_module_get(a->owner)) {
read_unlock(&act_mod_lock);
return NULL;
}
break;
}
}
read_unlock(&act_mod_lock);
}
return a;
}
#endif
int tcf_action_exec(struct sk_buff *skb, const struct tc_action *act,
struct tcf_result *res)
{
const struct tc_action *a;
int ret = -1;
if (skb->tc_verd & TC_NCLS) {
skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
ret = TC_ACT_OK;
goto exec_done;
}
while ((a = act) != NULL) {
repeat:
if (a->ops && a->ops->act) {
ret = a->ops->act(skb, a, res);
if (TC_MUNGED & skb->tc_verd) {
/* copied already, allow trampling */
skb->tc_verd = SET_TC_OK2MUNGE(skb->tc_verd);
skb->tc_verd = CLR_TC_MUNGED(skb->tc_verd);
}
if (ret == TC_ACT_REPEAT)
goto repeat; /* we need a ttl - JHS */
if (ret != TC_ACT_PIPE)
goto exec_done;
}
act = a->next;
}
exec_done:
return ret;
}
EXPORT_SYMBOL(tcf_action_exec);
void tcf_action_destroy(struct tc_action *act, int bind)
{
struct tc_action *a;
for (a = act; a; a = act) {
if (a->ops && a->ops->cleanup) {
if (a->ops->cleanup(a, bind) == ACT_P_DELETED)
module_put(a->ops->owner);
act = act->next;
kfree(a);
} else {
/*FIXME: Remove later - catch insertion bugs*/
WARN(1, "tcf_action_destroy: BUG? destroying NULL ops\n");
act = act->next;
kfree(a);
}
}
}
int
tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
{
int err = -EINVAL;
if (a->ops == NULL || a->ops->dump == NULL)
return err;
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 (a->ops == NULL || a->ops->dump == NULL)
return err;
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 tc_action *act, int bind, int ref)
{
struct tc_action *a;
int err = -EINVAL;
struct nlattr *nest;
while ((a = act) != NULL) {
act = a->next;
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;
}
err = -ENOMEM;
a = kzalloc(sizeof(*a), GFP_KERNEL);
if (a == NULL)
goto err_mod;
/* 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_free;
/* 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);
a->ops = a_o;
return a;
err_free:
kfree(a);
err_mod:
module_put(a_o->owner);
err_out:
return ERR_PTR(err);
}
struct tc_action *tcf_action_init(struct net *net, struct nlattr *nla,
struct nlattr *est, char *name, int ovr,
int bind)
{
struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
struct tc_action *head = NULL, *act, *act_prev = NULL;
int err;
int i;
err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
if (err < 0)
return ERR_PTR(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))
goto err;
act->order = i;
if (head == NULL)
head = act;
else
act_prev->next = act;
act_prev = act;
}
return head;
err:
if (head != NULL)
tcf_action_destroy(head, bind);
return act;
}
int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *a,
int compat_mode)
{
int err = 0;
struct gnet_dump d;
struct tcf_act_hdr *h = a->priv;
if (h == NULL)
goto errout;
/* compat_mode being true specifies a call that is supposed
* to add additional backward compatibility statistic TLVs.
*/
if (compat_mode) {
if (a->type == TCA_OLD_COMPAT)
err = gnet_stats_start_copy_compat(skb, 0,
TCA_STATS, TCA_XSTATS, &h->tcf_lock, &d);
else
return 0;
} else
err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
&h->tcf_lock, &d);
if (err < 0)
goto errout;
if (a->ops != NULL && a->ops->get_stats != NULL)
if (a->ops->get_stats(skb, a) < 0)
goto errout;
if (gnet_stats_copy_basic(&d, &h->tcf_bstats) < 0 ||
gnet_stats_copy_rate_est(&d, &h->tcf_bstats,
&h->tcf_rate_est) < 0 ||
gnet_stats_copy_queue(&d, &h->tcf_qstats) < 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 tc_action *a, 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, a, 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 tc_action *a, int event)
{
struct sk_buff *skb;
skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (!skb)
return -ENOBUFS;
if (tca_get_fill(skb, a, 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 nlattr *nla, struct nlmsghdr *n, u32 portid)
{
struct nlattr *tb[TCA_ACT_MAX + 1];
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 = -ENOMEM;
a = kzalloc(sizeof(struct tc_action), GFP_KERNEL);
if (a == NULL)
goto err_out;
err = -EINVAL;
a->ops = tc_lookup_action(tb[TCA_ACT_KIND]);
if (a->ops == NULL)
goto err_free;
if (a->ops->lookup == NULL)
goto err_mod;
err = -ENOENT;
if (a->ops->lookup(a, index) == 0)
goto err_mod;
module_put(a->ops->owner);
return a;
err_mod:
module_put(a->ops->owner);
err_free:
kfree(a);
err_out:
return ERR_PTR(err);
}
static void cleanup_a(struct tc_action *act)
{
struct tc_action *a;
for (a = act; a; a = act) {
act = a->next;
kfree(a);
}
}
static struct tc_action *create_a(int i)
{
struct tc_action *act;
act = kzalloc(sizeof(*act), GFP_KERNEL);
if (act == NULL) {
pr_debug("create_a: failed to alloc!\n");
return NULL;
}
act->order = i;
return act;
}
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];
struct nlattr *kind;
struct tc_action *a = create_a(0);
int err = -ENOMEM;
if (a == NULL) {
pr_debug("tca_action_flush: couldnt create tc_action\n");
return err;
}
skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (!skb) {
pr_debug("tca_action_flush: failed skb alloc\n");
kfree(a);
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];
a->ops = tc_lookup_action(kind);
if (a->ops == NULL)
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 = a->ops->walk(skb, &dcb, RTM_DELACTION, a);
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(a->ops->owner);
kfree(a);
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(a->ops->owner);
err_out:
noflush_out:
kfree_skb(skb);
kfree(a);
return err;
}
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 *head = NULL, *act, *act_prev = NULL;
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(tb[i], n, portid);
if (IS_ERR(act)) {
ret = PTR_ERR(act);
goto err;
}
act->order = i;
if (head == NULL)
head = act;
else
act_prev->next = act;
act_prev = act;
}
if (event == RTM_GETACTION)
ret = act_get_notify(net, portid, n, head, event);
else { /* delete */
struct sk_buff *skb;
skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (!skb) {
ret = -ENOBUFS;
goto err;
}
if (tca_get_fill(skb, head, portid, n->nlmsg_seq, 0, event,
0, 1) <= 0) {
kfree_skb(skb);
ret = -EINVAL;
goto err;
}
/* now do the delete */
tcf_action_destroy(head, 0);
ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
n->nlmsg_flags & NLM_F_ECHO);
if (ret > 0)
return 0;
return ret;
}
err:
cleanup_a(head);
return ret;
}
static int tcf_add_notify(struct net *net, struct tc_action *a,
u32 portid, u32 seq, int event, u16 flags)
{
struct tcamsg *t;
struct nlmsghdr *nlh;
struct sk_buff *skb;
struct nlattr *nest;
unsigned char *b;
int err = 0;
skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (!skb)
return -ENOBUFS;
b = skb_tail_pointer(skb);
nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
if (!nlh)
goto out_kfree_skb;
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_kfree_skb;
if (tcf_action_dump(skb, a, 0, 0) < 0)
goto out_kfree_skb;
nla_nest_end(skb, nest);
nlh->nlmsg_len = skb_tail_pointer(skb) - b;
NETLINK_CB(skb).dst_group = RTNLGRP_TC;
err = rtnetlink_send(skb, net, portid, RTNLGRP_TC, flags & NLM_F_ECHO);
if (err > 0)
err = 0;
return err;
out_kfree_skb:
kfree_skb(skb);
return -1;
}
static int
tcf_action_add(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
u32 portid, int ovr)
{
int ret = 0;
struct tc_action *act;
struct tc_action *a;
u32 seq = n->nlmsg_seq;
act = tcf_action_init(net, nla, NULL, NULL, ovr, 0);
if (act == NULL)
goto done;
if (IS_ERR(act)) {
ret = PTR_ERR(act);
goto done;
}
/* dump then free all the actions after update; inserted policy
* stays intact
*/
ret = tcf_add_notify(net, act, portid, seq, RTM_NEWACTION, n->nlmsg_flags);
for (a = act; a; a = act) {
act = a->next;
kfree(a);
}
done:
return ret;
}
static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
{
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) && !capable(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 nlmsghdr *nlh;
unsigned char *b = skb_tail_pointer(skb);
struct nlattr *nest;
struct tc_action_ops *a_o;
struct tc_action a;
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;
memset(&a, 0, sizeof(struct tc_action));
a.ops = a_o;
if (a_o->walk == NULL) {
WARN(1, "tc_dump_action: %s !capable of dumping table\n",
a_o->kind);
goto out_module_put;
}
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(skb, cb, RTM_GETACTION, &a);
if (ret < 0)
goto out_module_put;
if (ret > 0) {
nla_nest_end(skb, nest);
ret = skb->len;
} else
nla_nest_cancel(skb, nest);
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);