1 files changed, 314 insertions, 0 deletions
diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c
new file mode 100644
index 0000000..0453d79
--- /dev/null
+++ b/net/sched/act_ipt.c
@@ -0,0 +1,314 @@
+/*
+ * 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 <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/skbuff.h>
+#include <linux/rtnetlink.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <net/netlink.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>
+
+
+#define IPT_TAB_MASK     15
+static struct tcf_common *tcf_ipt_ht[IPT_TAB_MASK + 1];
+static u32 ipt_idx_gen;
+static DEFINE_RWLOCK(ipt_lock);
+
+static struct tcf_hashinfo ipt_hash_info = {
+	.htab	=	tcf_ipt_ht,
+	.hmask	=	IPT_TAB_MASK,
+	.lock	=	&ipt_lock,
+};
+
+static int ipt_init_target(struct ipt_entry_target *t, char *table, unsigned int hook)
+{
+	struct xt_tgchk_param par;
+	struct xt_target *target;
+	int ret = 0;
+
+	target = xt_request_find_target(AF_INET, t->u.user.name,
+					t->u.user.revision);
+	if (!target)
+		return -ENOENT;
+
+	t->u.kernel.target = target;
+	par.table     = table;
+	par.entryinfo = NULL;
+	par.target    = target;
+	par.targinfo  = t->data;
+	par.hook_mask = hook;
+	par.family    = NFPROTO_IPV4;
+
+	ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false);
+	if (ret < 0) {
+		module_put(t->u.kernel.target->me);
+		return ret;
+	}
+	return 0;
+}
+
+static void ipt_destroy_target(struct ipt_entry_target *t)
+{
+	struct xt_tgdtor_param par = {
+		.target   = t->u.kernel.target,
+		.targinfo = t->data,
+	};
+	if (par.target->destroy != NULL)
+		par.target->destroy(&par);
+	module_put(par.target->me);
+}
+
+static int tcf_ipt_release(struct tcf_ipt *ipt, int bind)
+{
+	int ret = 0;
+	if (ipt) {
+		if (bind)
+			ipt->tcf_bindcnt--;
+		ipt->tcf_refcnt--;
+		if (ipt->tcf_bindcnt <= 0 && ipt->tcf_refcnt <= 0) {
+			ipt_destroy_target(ipt->tcfi_t);
+			kfree(ipt->tcfi_tname);
+			kfree(ipt->tcfi_t);
+			tcf_hash_destroy(&ipt->common, &ipt_hash_info);
+			ret = ACT_P_DELETED;
+		}
+	}
+	return ret;
+}
+
+static const struct nla_policy ipt_policy[TCA_IPT_MAX + 1] = {
+	[TCA_IPT_TABLE]	= { .type = NLA_STRING, .len = IFNAMSIZ },
+	[TCA_IPT_HOOK]	= { .type = NLA_U32 },
+	[TCA_IPT_INDEX]	= { .type = NLA_U32 },
+	[TCA_IPT_TARG]	= { .len = sizeof(struct ipt_entry_target) },
+};
+
+static int tcf_ipt_init(struct nlattr *nla, struct nlattr *est,
+			struct tc_action *a, int ovr, int bind)
+{
+	struct nlattr *tb[TCA_IPT_MAX + 1];
+	struct tcf_ipt *ipt;
+	struct tcf_common *pc;
+	struct ipt_entry_target *td, *t;
+	char *tname;
+	int ret = 0, err;
+	u32 hook = 0;
+	u32 index = 0;
+
+	if (nla == NULL)
+		return -EINVAL;
+
+	err = nla_parse_nested(tb, TCA_IPT_MAX, nla, ipt_policy);
+	if (err < 0)
+		return err;
+
+	if (tb[TCA_IPT_HOOK] == NULL)
+		return -EINVAL;
+	if (tb[TCA_IPT_TARG] == NULL)
+		return -EINVAL;
+
+	td = (struct ipt_entry_target *)nla_data(tb[TCA_IPT_TARG]);
+	if (nla_len(tb[TCA_IPT_TARG]) < td->u.target_size)
+		return -EINVAL;
+
+	if (tb[TCA_IPT_INDEX] != NULL)
+		index = nla_get_u32(tb[TCA_IPT_INDEX]);
+
+	pc = tcf_hash_check(index, a, bind, &ipt_hash_info);
+	if (!pc) {
+		pc = tcf_hash_create(index, est, a, sizeof(*ipt), bind,
+				     &ipt_idx_gen, &ipt_hash_info);
+		if (unlikely(!pc))
+			return -ENOMEM;
+		ret = ACT_P_CREATED;
+	} else {
+		if (!ovr) {
+			tcf_ipt_release(to_ipt(pc), bind);
+			return -EEXIST;
+		}
+	}
+	ipt = to_ipt(pc);
+
+	hook = nla_get_u32(tb[TCA_IPT_HOOK]);
+
+	err = -ENOMEM;
+	tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
+	if (unlikely(!tname))
+		goto err1;
+	if (tb[TCA_IPT_TABLE] == NULL ||
+	    nla_strlcpy(tname, tb[TCA_IPT_TABLE], IFNAMSIZ) >= IFNAMSIZ)
+		strcpy(tname, "mangle");
+
+	t = kmemdup(td, td->u.target_size, GFP_KERNEL);
+	if (unlikely(!t))
+		goto err2;
+
+	if ((err = ipt_init_target(t, tname, hook)) < 0)
+		goto err3;
+
+	spin_lock_bh(&ipt->tcf_lock);
+	if (ret != ACT_P_CREATED) {
+		ipt_destroy_target(ipt->tcfi_t);
+		kfree(ipt->tcfi_tname);
+		kfree(ipt->tcfi_t);
+	}
+	ipt->tcfi_tname = tname;
+	ipt->tcfi_t     = t;
+	ipt->tcfi_hook  = hook;
+	spin_unlock_bh(&ipt->tcf_lock);
+	if (ret == ACT_P_CREATED)
+		tcf_hash_insert(pc, &ipt_hash_info);
+	return ret;
+
+err3:
+	kfree(t);
+err2:
+	kfree(tname);
+err1:
+	kfree(pc);
+	return err;
+}
+
+static int tcf_ipt_cleanup(struct tc_action *a, int bind)
+{
+	struct tcf_ipt *ipt = a->priv;
+	return tcf_ipt_release(ipt, bind);
+}
+
+static int tcf_ipt(struct sk_buff *skb, struct tc_action *a,
+		   struct tcf_result *res)
+{
+	int ret = 0, result = 0;
+	struct tcf_ipt *ipt = a->priv;
+	struct xt_target_param par;
+
+	if (skb_cloned(skb)) {
+		if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
+			return TC_ACT_UNSPEC;
+	}
+
+	spin_lock(&ipt->tcf_lock);
+
+	ipt->tcf_tm.lastuse = jiffies;
+	ipt->tcf_bstats.bytes += qdisc_pkt_len(skb);
+	ipt->tcf_bstats.packets++;
+
+	/* yes, we have to worry about both in and out dev
+	 worry later - danger - this API seems to have changed
+	 from earlier kernels */
+	par.in       = skb->dev;
+	par.out      = NULL;
+	par.hooknum  = ipt->tcfi_hook;
+	par.target   = ipt->tcfi_t->u.kernel.target;
+	par.targinfo = ipt->tcfi_t->data;
+	ret = par.target->target(skb, &par);
+
+	switch (ret) {
+	case NF_ACCEPT:
+		result = TC_ACT_OK;
+		break;
+	case NF_DROP:
+		result = TC_ACT_SHOT;
+		ipt->tcf_qstats.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(&ipt->tcf_lock);
+	return result;
+
+}
+
+static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
+{
+	unsigned char *b = skb_tail_pointer(skb);
+	struct tcf_ipt *ipt = a->priv;
+	struct ipt_entry_target *t;
+	struct tcf_t tm;
+	struct tc_cnt c;
+
+	/* for simple targets kernel size == user size
+	** user name = target name
+	** for foolproof you need to not assume this
+	*/
+
+	t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC);
+	if (unlikely(!t))
+		goto nla_put_failure;
+
+	c.bindcnt = ipt->tcf_bindcnt - bind;
+	c.refcnt = ipt->tcf_refcnt - ref;
+	strcpy(t->u.user.name, ipt->tcfi_t->u.kernel.target->name);
+
+	NLA_PUT(skb, TCA_IPT_TARG, ipt->tcfi_t->u.user.target_size, t);
+	NLA_PUT_U32(skb, TCA_IPT_INDEX, ipt->tcf_index);
+	NLA_PUT_U32(skb, TCA_IPT_HOOK, ipt->tcfi_hook);
+	NLA_PUT(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c);
+	NLA_PUT_STRING(skb, TCA_IPT_TABLE, ipt->tcfi_tname);
+	tm.install = jiffies_to_clock_t(jiffies - ipt->tcf_tm.install);
+	tm.lastuse = jiffies_to_clock_t(jiffies - ipt->tcf_tm.lastuse);
+	tm.expires = jiffies_to_clock_t(ipt->tcf_tm.expires);
+	NLA_PUT(skb, TCA_IPT_TM, sizeof (tm), &tm);
+	kfree(t);
+	return skb->len;
+
+nla_put_failure:
+	nlmsg_trim(skb, b);
+	kfree(t);
+	return -1;
+}
+
+static struct tc_action_ops act_ipt_ops = {
+	.kind		=	"ipt",
+	.hinfo		=	&ipt_hash_info,
+	.type		=	TCA_ACT_IPT,
+	.capab		=	TCA_CAP_NONE,
+	.owner		=	THIS_MODULE,
+	.act		=	tcf_ipt,
+	.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);