1 files changed, 300 insertions, 0 deletions
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
new file mode 100644
index 00000000..961386e2
--- /dev/null
+++ b/net/sched/act_mirred.c
@@ -0,0 +1,300 @@
+/*
+ * net/sched/mirred.c	packet mirroring and redirect actions
+ *
+ *		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.
+ *
+ * Authors:	Jamal Hadi Salim (2002-4)
+ *
+ * TODO: Add ingress support (and socket redirect support)
+ *
+ */
+
+#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 <linux/gfp.h>
+#include <net/net_namespace.h>
+#include <net/netlink.h>
+#include <net/pkt_sched.h>
+#include <linux/tc_act/tc_mirred.h>
+#include <net/tc_act/tc_mirred.h>
+
+#include <linux/if_arp.h>
+
+#define MIRRED_TAB_MASK     7
+static struct tcf_common *tcf_mirred_ht[MIRRED_TAB_MASK + 1];
+static u32 mirred_idx_gen;
+static DEFINE_RWLOCK(mirred_lock);
+static LIST_HEAD(mirred_list);
+
+static struct tcf_hashinfo mirred_hash_info = {
+	.htab	=	tcf_mirred_ht,
+	.hmask	=	MIRRED_TAB_MASK,
+	.lock	=	&mirred_lock,
+};
+
+static int tcf_mirred_release(struct tcf_mirred *m, int bind)
+{
+	if (m) {
+		if (bind)
+			m->tcf_bindcnt--;
+		m->tcf_refcnt--;
+		if (!m->tcf_bindcnt && m->tcf_refcnt <= 0) {
+			list_del(&m->tcfm_list);
+			if (m->tcfm_dev)
+				dev_put(m->tcfm_dev);
+			tcf_hash_destroy(&m->common, &mirred_hash_info);
+			return 1;
+		}
+	}
+	return 0;
+}
+
+static const struct nla_policy mirred_policy[TCA_MIRRED_MAX + 1] = {
+	[TCA_MIRRED_PARMS]	= { .len = sizeof(struct tc_mirred) },
+};
+
+static int tcf_mirred_init(struct nlattr *nla, struct nlattr *est,
+			   struct tc_action *a, int ovr, int bind)
+{
+	struct nlattr *tb[TCA_MIRRED_MAX + 1];
+	struct tc_mirred *parm;
+	struct tcf_mirred *m;
+	struct tcf_common *pc;
+	struct net_device *dev;
+	int ret, ok_push = 0;
+
+	if (nla == NULL)
+		return -EINVAL;
+	ret = nla_parse_nested(tb, TCA_MIRRED_MAX, nla, mirred_policy);
+	if (ret < 0)
+		return ret;
+	if (tb[TCA_MIRRED_PARMS] == NULL)
+		return -EINVAL;
+	parm = nla_data(tb[TCA_MIRRED_PARMS]);
+	switch (parm->eaction) {
+	case TCA_EGRESS_MIRROR:
+	case TCA_EGRESS_REDIR:
+		break;
+	default:
+		return -EINVAL;
+	}
+	if (parm->ifindex) {
+		dev = __dev_get_by_index(&init_net, parm->ifindex);
+		if (dev == NULL)
+			return -ENODEV;
+		switch (dev->type) {
+		case ARPHRD_TUNNEL:
+		case ARPHRD_TUNNEL6:
+		case ARPHRD_SIT:
+		case ARPHRD_IPGRE:
+		case ARPHRD_VOID:
+		case ARPHRD_NONE:
+			ok_push = 0;
+			break;
+		default:
+			ok_push = 1;
+			break;
+		}
+	} else {
+		dev = NULL;
+	}
+
+	pc = tcf_hash_check(parm->index, a, bind, &mirred_hash_info);
+	if (!pc) {
+		if (dev == NULL)
+			return -EINVAL;
+		pc = tcf_hash_create(parm->index, est, a, sizeof(*m), bind,
+				     &mirred_idx_gen, &mirred_hash_info);
+		if (IS_ERR(pc))
+			return PTR_ERR(pc);
+		ret = ACT_P_CREATED;
+	} else {
+		if (!ovr) {
+			tcf_mirred_release(to_mirred(pc), bind);
+			return -EEXIST;
+		}
+	}
+	m = to_mirred(pc);
+
+	spin_lock_bh(&m->tcf_lock);
+	m->tcf_action = parm->action;
+	m->tcfm_eaction = parm->eaction;
+	if (dev != NULL) {
+		m->tcfm_ifindex = parm->ifindex;
+		if (ret != ACT_P_CREATED)
+			dev_put(m->tcfm_dev);
+		dev_hold(dev);
+		m->tcfm_dev = dev;
+		m->tcfm_ok_push = ok_push;
+	}
+	spin_unlock_bh(&m->tcf_lock);
+	if (ret == ACT_P_CREATED) {
+		list_add(&m->tcfm_list, &mirred_list);
+		tcf_hash_insert(pc, &mirred_hash_info);
+	}
+
+	return ret;
+}
+
+static int tcf_mirred_cleanup(struct tc_action *a, int bind)
+{
+	struct tcf_mirred *m = a->priv;
+
+	if (m)
+		return tcf_mirred_release(m, bind);
+	return 0;
+}
+
+static int tcf_mirred(struct sk_buff *skb, struct tc_action *a,
+		      struct tcf_result *res)
+{
+	struct tcf_mirred *m = a->priv;
+	struct net_device *dev;
+	struct sk_buff *skb2;
+	u32 at;
+	int retval, err = 1;
+
+	spin_lock(&m->tcf_lock);
+	m->tcf_tm.lastuse = jiffies;
+	bstats_update(&m->tcf_bstats, skb);
+
+	dev = m->tcfm_dev;
+	if (!dev) {
+		printk_once(KERN_NOTICE "tc mirred: target device is gone\n");
+		goto out;
+	}
+
+	if (!(dev->flags & IFF_UP)) {
+		if (net_ratelimit())
+			pr_notice("tc mirred to Houston: device %s is down\n",
+				  dev->name);
+		goto out;
+	}
+
+	at = G_TC_AT(skb->tc_verd);
+	skb2 = skb_act_clone(skb, GFP_ATOMIC, m->tcf_action);
+	if (skb2 == NULL)
+		goto out;
+
+	if (!(at & AT_EGRESS)) {
+		if (m->tcfm_ok_push)
+			skb_push(skb2, skb2->dev->hard_header_len);
+	}
+
+	/* mirror is always swallowed */
+	if (m->tcfm_eaction != TCA_EGRESS_MIRROR)
+		skb2->tc_verd = SET_TC_FROM(skb2->tc_verd, at);
+
+	skb2->skb_iif = skb->dev->ifindex;
+	skb2->dev = dev;
+	dev_queue_xmit(skb2);
+	err = 0;
+
+out:
+	if (err) {
+		m->tcf_qstats.overlimits++;
+		/* should we be asking for packet to be dropped?
+		 * may make sense for redirect case only
+		 */
+		retval = TC_ACT_SHOT;
+	} else {
+		retval = m->tcf_action;
+	}
+	spin_unlock(&m->tcf_lock);
+
+	return retval;
+}
+
+static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
+{
+	unsigned char *b = skb_tail_pointer(skb);
+	struct tcf_mirred *m = a->priv;
+	struct tc_mirred opt = {
+		.index   = m->tcf_index,
+		.action  = m->tcf_action,
+		.refcnt  = m->tcf_refcnt - ref,
+		.bindcnt = m->tcf_bindcnt - bind,
+		.eaction = m->tcfm_eaction,
+		.ifindex = m->tcfm_ifindex,
+	};
+	struct tcf_t t;
+
+	NLA_PUT(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt);
+	t.install = jiffies_to_clock_t(jiffies - m->tcf_tm.install);
+	t.lastuse = jiffies_to_clock_t(jiffies - m->tcf_tm.lastuse);
+	t.expires = jiffies_to_clock_t(m->tcf_tm.expires);
+	NLA_PUT(skb, TCA_MIRRED_TM, sizeof(t), &t);
+	return skb->len;
+
+nla_put_failure:
+	nlmsg_trim(skb, b);
+	return -1;
+}
+
+static int mirred_device_event(struct notifier_block *unused,
+			       unsigned long event, void *ptr)
+{
+	struct net_device *dev = ptr;
+	struct tcf_mirred *m;
+
+	if (event == NETDEV_UNREGISTER)
+		list_for_each_entry(m, &mirred_list, tcfm_list) {
+			if (m->tcfm_dev == dev) {
+				dev_put(dev);
+				m->tcfm_dev = NULL;
+			}
+		}
+
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block mirred_device_notifier = {
+	.notifier_call = mirred_device_event,
+};
+
+
+static struct tc_action_ops act_mirred_ops = {
+	.kind		=	"mirred",
+	.hinfo		=	&mirred_hash_info,
+	.type		=	TCA_ACT_MIRRED,
+	.capab		=	TCA_CAP_NONE,
+	.owner		=	THIS_MODULE,
+	.act		=	tcf_mirred,
+	.dump		=	tcf_mirred_dump,
+	.cleanup	=	tcf_mirred_cleanup,
+	.lookup		=	tcf_hash_search,
+	.init		=	tcf_mirred_init,
+	.walk		=	tcf_generic_walker
+};
+
+MODULE_AUTHOR("Jamal Hadi Salim(2002)");
+MODULE_DESCRIPTION("Device Mirror/redirect actions");
+MODULE_LICENSE("GPL");
+
+static int __init mirred_init_module(void)
+{
+	int err = register_netdevice_notifier(&mirred_device_notifier);
+	if (err)
+		return err;
+
+	pr_info("Mirror/redirect action on\n");
+	return tcf_register_action(&act_mirred_ops);
+}
+
+static void __exit mirred_cleanup_module(void)
+{
+	unregister_netdevice_notifier(&mirred_device_notifier);
+	tcf_unregister_action(&act_mirred_ops);
+}
+
+module_init(mirred_init_module);
+module_exit(mirred_cleanup_module);