blob: f2e9ed34a963e1a06dbefb792836919d92bf6733 [file] [log] [blame]
/*
* 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/pkt_cls.h>
#include <net/act_api.h>
#include <net/netlink.h>
static int tcf_action_goto_chain_init(struct tc_action *a, struct tcf_proto *tp)
{
u32 chain_index = a->tcfa_action & TC_ACT_EXT_VAL_MASK;
if (!tp)
return -EINVAL;
a->goto_chain = tcf_chain_get(tp->chain->block, chain_index, true);
if (!a->goto_chain)
return -ENOMEM;
return 0;
}
static void tcf_action_goto_chain_fini(struct tc_action *a)
{
tcf_chain_put(a->goto_chain);
}
static void tcf_action_goto_chain_exec(const struct tc_action *a,
struct tcf_result *res)
{
const struct tcf_chain *chain = a->goto_chain;
res->goto_tp = rcu_dereference_bh(chain->filter_chain);
}
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);
if (p->act_cookie) {
kfree(p->act_cookie->data);
kfree(p->act_cookie);
}
if (p->goto_chain)
tcf_action_goto_chain_fini(p);
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_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_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;
/* We have to register pernet ops before making the action ops visible,
* otherwise tcf_action_init_1() could get a partially initialized
* netns.
*/
ret = register_pernet_subsys(ops);
if (ret)
return ret;
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);
unregister_pernet_subsys(ops);
return -EEXIST;
}
}
list_add_tail(&act->head, &act_base);
write_unlock(&act_mod_lock);
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;
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);
if (!err)
unregister_pernet_subsys(ops);
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;
}
/*TCA_ACT_MAX_PRIO is 32, there count upto 32 */
#define TCA_ACT_MAX_PRIO_MASK 0x1FF
int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
int nr_actions, struct tcf_result *res)
{
int ret = -1, i;
u32 jmp_prgcnt = 0;
u32 jmp_ttl = TCA_ACT_MAX_PRIO; /*matches actions per filter */
if (skb_skip_tc_classify(skb))
return TC_ACT_OK;
restart_act_graph:
for (i = 0; i < nr_actions; i++) {
const struct tc_action *a = actions[i];
if (jmp_prgcnt > 0) {
jmp_prgcnt -= 1;
continue;
}
repeat:
ret = a->ops->act(skb, a, res);
if (ret == TC_ACT_REPEAT)
goto repeat; /* we need a ttl - JHS */
if (TC_ACT_EXT_CMP(ret, TC_ACT_JUMP)) {
jmp_prgcnt = ret & TCA_ACT_MAX_PRIO_MASK;
if (!jmp_prgcnt || (jmp_prgcnt > nr_actions)) {
/* faulty opcode, stop pipeline */
return TC_ACT_OK;
} else {
jmp_ttl -= 1;
if (jmp_ttl > 0)
goto restart_act_graph;
else /* faulty graph, stop pipeline */
return TC_ACT_OK;
}
} else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
tcf_action_goto_chain_exec(a, res);
}
if (ret != TC_ACT_PIPE)
break;
}
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;
if (a->act_cookie) {
if (nla_put(skb, TCA_ACT_COOKIE, a->act_cookie->len,
a->act_cookie->data))
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;
}
static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
{
struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL);
if (!c)
return NULL;
c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL);
if (!c->data) {
kfree(c);
return NULL;
}
c->len = nla_len(tb[TCA_ACT_COOKIE]);
return c;
}
struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
struct nlattr *nla, struct nlattr *est,
char *name, int ovr, int bind)
{
struct tc_action *a;
struct tc_action_ops *a_o;
struct tc_cookie *cookie = NULL;
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, 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;
if (tb[TCA_ACT_COOKIE]) {
int cklen = nla_len(tb[TCA_ACT_COOKIE]);
if (cklen > TC_COOKIE_MAX_SIZE)
goto err_out;
cookie = nla_memdup_cookie(tb);
if (!cookie) {
err = -ENOMEM;
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;
if (name == NULL && tb[TCA_ACT_COOKIE]) {
if (a->act_cookie) {
kfree(a->act_cookie->data);
kfree(a->act_cookie);
}
a->act_cookie = cookie;
}
/* 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);
if (TC_ACT_EXT_CMP(a->tcfa_action, TC_ACT_GOTO_CHAIN)) {
err = tcf_action_goto_chain_init(a, tp);
if (err) {
LIST_HEAD(actions);
list_add_tail(&a->list, &actions);
tcf_action_destroy(&actions, bind);
return ERR_PTR(err);
}
}
return a;
err_mod:
module_put(a_o->owner);
err_out:
if (cookie) {
kfree(cookie->data);
kfree(cookie);
}
return ERR_PTR(err);
}
static void cleanup_a(struct list_head *actions, int ovr)
{
struct tc_action *a;
if (!ovr)
return;
list_for_each_entry(a, actions, list)
a->tcfa_refcnt--;
}
int tcf_action_init(struct net *net, struct tcf_proto *tp, 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, NULL);
if (err < 0)
return err;
for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
act = tcf_action_init_1(net, tp, tb[i], est, name, ovr, bind);
if (IS_ERR(act)) {
err = PTR_ERR(act);
goto err;
}
act->order = i;
if (ovr)
act->tcfa_refcnt++;
list_add_tail(&act->list, actions);
}
/* Remove the temp refcnt which was necessary to protect against
* destroying an existing action which was being replaced
*/
cleanup_a(actions, ovr);
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_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
tcf_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, 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, 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;
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:
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, 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 = tcf_get_notify(net, portid, n, &actions, event);
else { /* delete */
ret = tcf_del_notify(net, n, &actions, portid);
if (ret)
goto err;
return ret;
}
err:
if (event != RTM_GETACTION)
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, NULL, 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 netlink_ext_ack *extack)
{
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,
extack);
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, 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, NULL) < 0)
return NULL;
if (tb[1] == NULL)
return NULL;
if (nla_parse_nested(tb2, TCA_ACT_MAX, tb[1], NULL, 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);