[PKT_SCHED]: Add iptables action.

Signed-off-by: jamal <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/tc_act/tc_ipt.h

+#ifndef __LINUX_TC_IPT_H
+#define __LINUX_TC_IPT_H
+
+#include <linux/pkt_cls.h>
+
+#define TCA_ACT_IPT 6
+
+enum
+{
+	TCA_IPT_UNSPEC,
+	TCA_IPT_TABLE,
+	TCA_IPT_HOOK,
+	TCA_IPT_INDEX,
+	TCA_IPT_CNT,
+	TCA_IPT_TM,
+	TCA_IPT_TARG,
+	__TCA_IPT_MAX
+};
+#define TCA_IPT_MAX (__TCA_IPT_MAX - 1)
+                                                                                
+#endif

include/net/tc_act/tc_ipt.h

+#ifndef __NET_TC_IPT_H
+#define __NET_TC_IPT_H
+
+#include <net/act_api.h>
+
+struct ipt_entry_target;
+
+struct tcf_ipt
+{
+	tca_gen(ipt);
+	u32 hook;
+	char *tname;
+	struct ipt_entry_target *t;
+};
+
+#endif

net/sched/Kconfig

@@ -407,6 +407,13 @@ config NET_ACT_MIRRED
         requires new iproute2
         This allows packets to be mirrored or redirected to netdevices
 
+config NET_ACT_IPT
+        tristate "iptables Actions"
+        depends on NET_CLS_ACT && NETFILTER && IP_NF_IPTABLES
+        ---help---
+        requires new iproute2
+        This allows iptables targets to be used by tc filters
+
 config NET_ACT_PEDIT
         tristate "Generic Packet Editor Actions"
         depends on NET_CLS_ACT

net/sched/Makefile

@@ -12,6 +12,7 @@ obj-$(CONFIG_NET_ACT_POLICE)	+= police.o
 obj-$(CONFIG_NET_CLS_POLICE)	+= police.o
 obj-$(CONFIG_NET_ACT_GACT)      += gact.o
 obj-$(CONFIG_NET_ACT_MIRRED)    += mirred.o
+obj-$(CONFIG_NET_ACT_IPT)       += ipt.o
 obj-$(CONFIG_NET_ACT_PEDIT)     += pedit.o
 obj-$(CONFIG_NET_SCH_CBQ)	+= sch_cbq.o
 obj-$(CONFIG_NET_SCH_HTB)	+= sch_htb.o

net/sched/ipt.c

+/*
+ * net/sched/ipt.c	iptables target interface
+ *
+ *TODO: Add other tables. For now we only support the ipv4 table targets
+ *
+ *		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.
+ *
+ * Copyright:	Jamal Hadi Salim (2002-4)
+ */
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/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/module.h>
+#include <linux/init.h>
+#include <linux/proc_fs.h>
+#include <net/sock.h>
+#include <net/pkt_sched.h>
+#include <linux/tc_act/tc_ipt.h>
+#include <net/tc_act/tc_ipt.h>
+
+#include <linux/netfilter_ipv4/ip_tables.h>
+
+/* use generic hash table */
+#define MY_TAB_SIZE     16
+#define MY_TAB_MASK     15
+
+u32 idx_gen;
+static struct tcf_ipt *tcf_ipt_ht[MY_TAB_SIZE];
+/* ipt hash table lock */
+static rwlock_t ipt_lock = RW_LOCK_UNLOCKED;
+
+/* ovewrride the defaults */
+#define tcf_st  tcf_ipt
+#define tcf_t_lock   ipt_lock
+#define tcf_ht tcf_ipt_ht
+
+#include <net/pkt_act.h>
+
+static inline int
+init_targ(struct tcf_ipt *p)
+{
+	struct ipt_target *target;
+	int ret = 0;
+	struct ipt_entry_target *t = p->t;
+	target = __ipt_find_target_lock(t->u.user.name, &ret);
+
+	if (!target) {
+		printk("init_targ: Failed to find %s\n",
+		       t->u.kernel.target->name);
+		return -1;
+	}
+
+	DPRINTK("init_targ: found %s\n", target->name);
+	/* we really need proper ref counting
+	 seems to be only needed for modules?? Talk to laforge */
+/*      if (target->me)
+              __MOD_INC_USE_COUNT(target->me);
+*/
+	t->u.kernel.target = target;
+
+	__ipt_mutex_up();
+
+	if (t->u.kernel.target->checkentry
+	    && !t->u.kernel.target->checkentry(p->tname, NULL, t->data,
+					       t->u.target_size
+					       - sizeof (*t), p->hook)) {
+/*              if (t->u.kernel.target->me)
+	      __MOD_DEC_USE_COUNT(t->u.kernel.target->me);
+*/
+		DPRINTK("ip_tables: check failed for `%s'.\n",
+			t->u.kernel.target->name);
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+int
+tcf_ipt_init(struct rtattr *rta, struct rtattr *est, struct tc_action *a, int ovr, int bind)
+{
+	struct ipt_entry_target *t;
+	unsigned h;
+	struct rtattr *tb[TCA_IPT_MAX];
+	struct tcf_ipt *p;
+	int ret = 0;
+	u32 index = 0;
+	u32 hook = 0;
+
+	if (NULL == a || NULL == rta ||
+	    (rtattr_parse(tb, TCA_IPT_MAX, RTA_DATA(rta), RTA_PAYLOAD(rta)) <
+	     0)) {
+		return -1;
+	}
+
+
+	if (tb[TCA_IPT_INDEX - 1]) {
+		index = *(u32 *) RTA_DATA(tb[TCA_IPT_INDEX - 1]);
+		DPRINTK("ipt index %d\n", index);
+	}
+
+	if (index && (p = tcf_hash_lookup(index)) != NULL) {
+		a->priv = (void *) p;
+		spin_lock(&p->lock);
+		if (bind) {
+			p->bindcnt += 1;
+			p->refcnt += 1;
+		}
+		if (ovr) {
+			goto override;
+		}
+		spin_unlock(&p->lock);
+		return ret;
+	}
+
+	if (NULL == tb[TCA_IPT_TARG - 1] || NULL == tb[TCA_IPT_HOOK - 1]) {
+		return -1;
+	}
+
+	p = kmalloc(sizeof (*p), GFP_KERNEL);
+	if (p == NULL)
+		return -1;
+
+	memset(p, 0, sizeof (*p));
+	p->refcnt = 1;
+	ret = 1;
+	spin_lock_init(&p->lock);
+	p->stats_lock = &p->lock;
+	if (bind)
+		p->bindcnt = 1;
+
+override:
+	hook = *(u32 *) RTA_DATA(tb[TCA_IPT_HOOK - 1]);
+
+	t = (struct ipt_entry_target *) RTA_DATA(tb[TCA_IPT_TARG - 1]);
+
+	p->t = kmalloc(t->u.target_size, GFP_KERNEL);
+	if (p->t == NULL) {
+		if (ovr) {
+			printk("ipt policy messed up \n");
+			spin_unlock(&p->lock);
+			return -1;
+		}
+		kfree(p);
+		return -1;
+	}
+
+	memcpy(p->t, RTA_DATA(tb[TCA_IPT_TARG - 1]), t->u.target_size);
+	DPRINTK(" target NAME %s size %d data[0] %x data[1] %x\n",
+		t->u.user.name, t->u.target_size, t->data[0], t->data[1]);
+
+	p->tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
+
+	if (p->tname == NULL) {
+		if (ovr) {
+			printk("ipt policy messed up 2 \n");
+			spin_unlock(&p->lock);
+			return -1;
+		}
+		kfree(p->t);
+		kfree(p);
+		return -1;
+	} else {
+		int csize = IFNAMSIZ - 1;
+
+		memset(p->tname, 0, IFNAMSIZ);
+		if (tb[TCA_IPT_TABLE - 1]) {
+			if (strlen((char *) RTA_DATA(tb[TCA_IPT_TABLE - 1])) <
+			    csize)
+				csize = strlen(RTA_DATA(tb[TCA_IPT_TABLE - 1]));
+			strncpy(p->tname, RTA_DATA(tb[TCA_IPT_TABLE - 1]),
+				csize);
+			DPRINTK("table name %s\n", p->tname);
+		} else {
+			strncpy(p->tname, "mangle", 1 + strlen("mangle"));
+		}
+	}
+
+	if (0 > init_targ(p)) {
+		if (ovr) {
+			printk("ipt policy messed up 2 \n");
+			spin_unlock(&p->lock);
+			return -1;
+		}
+		kfree(p->tname);
+		kfree(p->t);
+		kfree(p);
+		return -1;
+	}
+
+	if (ovr) {
+		spin_unlock(&p->lock);
+		return -1;
+	}
+
+	p->index = index ? : tcf_hash_new_index();
+
+	p->tm.lastuse = jiffies;
+	/*
+	p->tm.expires = jiffies;
+	*/
+	p->tm.install = jiffies;
+#ifdef CONFIG_NET_ESTIMATOR
+	if (est) {
+		qdisc_new_estimator(&p->stats, p->stats_lock, est);
+	}
+#endif
+	h = tcf_hash(p->index);
+	write_lock_bh(&ipt_lock);
+	p->next = tcf_ipt_ht[h];
+	tcf_ipt_ht[h] = p;
+	write_unlock_bh(&ipt_lock);
+	a->priv = (void *) p;
+	return ret;
+
+}
+
+int
+tcf_ipt_cleanup(struct tc_action *a, int bind)
+{
+	struct tcf_ipt *p;
+	p = PRIV(a,ipt);
+	if (NULL != p)
+		return tcf_hash_release(p, bind);
+	return 0;
+}
+
+int
+tcf_ipt(struct sk_buff **pskb, struct tc_action *a)
+{
+	int ret = 0, result = 0;
+	struct tcf_ipt *p;
+	struct sk_buff *skb = *pskb;
+
+	p = PRIV(a,ipt);
+
+	if (NULL == p || NULL == skb) {
+		return -1;
+	}
+
+	spin_lock(&p->lock);
+
+	p->tm.lastuse = jiffies;
+	p->stats.bytes += skb->len;
+	p->stats.packets++;
+
+	if (skb_cloned(skb) ) {
+		if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) {
+			return -1;
+		}
+	}
+	/* yes, we have to worry about both in and out dev
+	 worry later - danger - this API seems to have changed
+	 from earlier kernels */
+
+	ret = p->t->u.kernel.target->target(&skb, skb->dev, NULL,
+					    p->hook, p->t->data, (void *)NULL);
+	switch (ret) {
+	case NF_ACCEPT:
+		result = TC_ACT_OK;
+		break;
+	case NF_DROP:
+		result = TC_ACT_SHOT;
+		p->stats.drops++;
+		break;
+	case IPT_CONTINUE:
+		result = TC_ACT_PIPE;
+		break;
+	default:
+		if (net_ratelimit())
+			printk("Bogus netfilter code %d assume ACCEPT\n", ret);
+		result = TC_POLICE_OK;
+		break;
+	}
+	spin_unlock(&p->lock);
+	return result;
+
+}
+
+int
+tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
+{
+	struct ipt_entry_target *t;
+	struct tcf_t tm;
+	struct tc_cnt c;
+	unsigned char *b = skb->tail;
+
+	struct tcf_ipt *p;
+
+	p = PRIV(a,ipt);
+	if (NULL == p) {
+		printk("BUG: tcf_ipt_dump called with NULL params\n");
+		goto rtattr_failure;
+	}
+	/* for simple targets kernel size == user size
+	** user name = target name
+	** for foolproof you need to not assume this
+	*/
+
+	t = kmalloc(p->t->u.user.target_size, GFP_ATOMIC);
+
+	if (NULL == t)
+		goto rtattr_failure;
+
+	c.bindcnt = p->bindcnt - bind;
+	c.refcnt = p->refcnt - ref;
+	memcpy(t, p->t, p->t->u.user.target_size);
+	strcpy(t->u.user.name, p->t->u.kernel.target->name);
+
+	DPRINTK("\ttcf_ipt_dump tablename %s length %d\n", p->tname,
+		strlen(p->tname));
+	DPRINTK
+	    ("\tdump target name %s size %d size user %d data[0] %x data[1] %x\n",
+	     p->t->u.kernel.target->name, p->t->u.target_size, p->t->u.user.target_size,
+	     p->t->data[0], p->t->data[1]);
+	RTA_PUT(skb, TCA_IPT_TARG, p->t->u.user.target_size, t);
+	RTA_PUT(skb, TCA_IPT_INDEX, 4, &p->index);
+	RTA_PUT(skb, TCA_IPT_HOOK, 4, &p->hook);
+	RTA_PUT(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c);
+	RTA_PUT(skb, TCA_IPT_TABLE, IFNAMSIZ, p->tname);
+	tm.install = jiffies - p->tm.install;
+	tm.lastuse = jiffies - p->tm.lastuse;
+	tm.expires = p->tm.expires;
+	RTA_PUT(skb, TCA_IPT_TM, sizeof (tm), &tm);
+	return skb->len;
+
+      rtattr_failure:
+	skb_trim(skb, b - skb->data);
+	return -1;
+}
+
+int
+tcf_ipt_stats(struct sk_buff *skb, struct tc_action *a)
+{
+	struct tcf_ipt *p;
+	p = PRIV(a,ipt);
+	if (NULL != p)
+		return qdisc_copy_stats(skb, &p->stats, p->stats_lock);
+
+	return 1;
+}
+
+struct tc_action_ops act_ipt_ops = {
+	.next		=	NULL,
+	.kind		=	"ipt",
+	.type		=	TCA_ACT_IPT,
+	.capab		=	TCA_CAP_NONE,
+	.owner		=	THIS_MODULE,
+	.act		=	tcf_ipt,
+	.get_stats	=	tcf_ipt_stats,
+	.dump		=	tcf_ipt_dump,
+	.cleanup	=	tcf_ipt_cleanup,
+	.lookup		=	tcf_hash_search,
+	.init		=	tcf_ipt_init,
+	.walk		=	tcf_generic_walker
+};
+
+MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
+MODULE_DESCRIPTION("Iptables target actions");
+MODULE_LICENSE("GPL");
+
+static int __init
+ipt_init_module(void)
+{
+	return tcf_register_action(&act_ipt_ops);
+}
+
+static void __exit
+ipt_cleanup_module(void)
+{
+	tcf_unregister_action(&act_ipt_ops);
+}
+
+module_init(ipt_init_module);
+module_exit(ipt_cleanup_module);