path: root/net/sched/act_api.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 <asm/uaccess.h>
#include <asm/system.h>
#include <linux/bitops.h>
#include <linux/config.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/in.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/init.h>
#include <linux/kmod.h>
#include <net/sock.h>
#include <net/sch_generic.h>
#include <net/act_api.h>

#if 0 /* control */
#define DPRINTK(format, args...) printk(KERN_DEBUG format, ##args)
#else
#define DPRINTK(format, args...)
#endif
#if 0 /* data */
#define D2PRINTK(format, args...) printk(KERN_DEBUG format, ##args)
#else
#define D2PRINTK(format, args...)
#endif

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;
}

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;
}

/* 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 rtattr */
static struct tc_action_ops *tc_lookup_action(struct rtattr *kind)
{
	struct tc_action_ops *a = NULL;

	if (kind) {
		read_lock(&act_mod_lock);
		for (a = act_base; a; a = a->next) {
			if (rtattr_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, struct tc_action *act,
                    struct tcf_result *res)
{
	struct tc_action *a;
	int ret = -1;

	if (skb->tc_verd & TC_NCLS) {
		skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
		D2PRINTK("(%p)tcf_action_exec: cleared TC_NCLS in %s out %s\n",
		         skb, skb->input_dev ? skb->input_dev->name : "xxx",
		         skb->dev->name);
		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;
}

void tcf_action_destroy(struct tc_action *act, int</