Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 1900 insertions, 0 deletions

diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
new file mode 100644
index 00000000000..e21c049ec62
--- /dev/null
+++ b/net/ipv4/ipmr.c
@@ -0,0 +1,1900 @@
+/*
+ *	IP multicast routing support for mrouted 3.6/3.8
+ *
+ *		(c) 1995 Alan Cox, <alan@redhat.com>
+ *	  Linux Consultancy and Custom Driver Development
+ *
+ *	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.
+ *
+ *	Version: $Id: ipmr.c,v 1.65 2001/10/31 21:55:54 davem Exp $
+ *
+ *	Fixes:
+ *	Michael Chastain	:	Incorrect size of copying.
+ *	Alan Cox		:	Added the cache manager code
+ *	Alan Cox		:	Fixed the clone/copy bug and device race.
+ *	Mike McLagan		:	Routing by source
+ *	Malcolm Beattie		:	Buffer handling fixes.
+ *	Alexey Kuznetsov	:	Double buffer free and other fixes.
+ *	SVR Anand		:	Fixed several multicast bugs and problems.
+ *	Alexey Kuznetsov	:	Status, optimisations and more.
+ *	Brad Parker		:	Better behaviour on mrouted upcall
+ *					overflow.
+ *      Carlos Picoto           :       PIMv1 Support
+ *	Pavlin Ivanov Radoslavov:	PIMv2 Registers must checksum only PIM header
+ *					Relax this requrement to work with older peers.
+ *
+ */
+
+#include <linux/config.h>
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <linux/timer.h>
+#include <linux/mm.h>
+#include <linux/kernel.h>
+#include <linux/fcntl.h>
+#include <linux/stat.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/inetdevice.h>
+#include <linux/igmp.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/mroute.h>
+#include <linux/init.h>
+#include <net/ip.h>
+#include <net/protocol.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <net/icmp.h>
+#include <net/udp.h>
+#include <net/raw.h>
+#include <linux/notifier.h>
+#include <linux/if_arp.h>
+#include <linux/netfilter_ipv4.h>
+#include <net/ipip.h>
+#include <net/checksum.h>
+
+#if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
+#define CONFIG_IP_PIMSM	1
+#endif
+
+static struct sock *mroute_socket;
+
+
+/* Big lock, protecting vif table, mrt cache and mroute socket state.
+   Note that the changes are semaphored via rtnl_lock.
+ */
+
+static DEFINE_RWLOCK(mrt_lock);
+
+/*
+ *	Multicast router control variables
+ */
+
+static struct vif_device vif_table[MAXVIFS];		/* Devices 		*/
+static int maxvif;
+
+#define VIF_EXISTS(idx) (vif_table[idx].dev != NULL)
+
+static int mroute_do_assert;				/* Set in PIM assert	*/
+static int mroute_do_pim;
+
+static struct mfc_cache *mfc_cache_array[MFC_LINES];	/* Forwarding cache	*/
+
+static struct mfc_cache *mfc_unres_queue;		/* Queue of unresolved entries */
+static atomic_t cache_resolve_queue_len;		/* Size of unresolved	*/
+
+/* Special spinlock for queue of unresolved entries */
+static DEFINE_SPINLOCK(mfc_unres_lock);
+
+/* We return to original Alan's scheme. Hash table of resolved
+   entries is changed only in process context and protected
+   with weak lock mrt_lock. Queue of unresolved entries is protected
+   with strong spinlock mfc_unres_lock.
+
+   In this case data path is free of exclusive locks at all.
+ */
+
+static kmem_cache_t *mrt_cachep;
+
+static int ip_mr_forward(struct sk_buff *skb, struct mfc_cache *cache, int local);
+static int ipmr_cache_report(struct sk_buff *pkt, vifi_t vifi, int assert);
+static int ipmr_fill_mroute(struct sk_buff *skb, struct mfc_cache *c, struct rtmsg *rtm);
+
+#ifdef CONFIG_IP_PIMSM_V2
+static struct net_protocol pim_protocol;
+#endif
+
+static struct timer_list ipmr_expire_timer;
+
+/* Service routines creating virtual interfaces: DVMRP tunnels and PIMREG */
+
+static
+struct net_device *ipmr_new_tunnel(struct vifctl *v)
+{
+	struct net_device  *dev;
+
+	dev = __dev_get_by_name("tunl0");
+
+	if (dev) {
+		int err;
+		struct ifreq ifr;
+		mm_segment_t	oldfs;
+		struct ip_tunnel_parm p;
+		struct in_device  *in_dev;
+
+		memset(&p, 0, sizeof(p));
+		p.iph.daddr = v->vifc_rmt_addr.s_addr;
+		p.iph.saddr = v->vifc_lcl_addr.s_addr;
+		p.iph.version = 4;
+		p.iph.ihl = 5;
+		p.iph.protocol = IPPROTO_IPIP;
+		sprintf(p.name, "dvmrp%d", v->vifc_vifi);
+		ifr.ifr_ifru.ifru_data = (void*)&p;
+
+		oldfs = get_fs(); set_fs(KERNEL_DS);
+		err = dev->do_ioctl(dev, &ifr, SIOCADDTUNNEL);
+		set_fs(oldfs);
+
+		dev = NULL;
+
+		if (err == 0 && (dev = __dev_get_by_name(p.name)) != NULL) {
+			dev->flags |= IFF_MULTICAST;
+
+			in_dev = __in_dev_get(dev);
+			if (in_dev == NULL && (in_dev = inetdev_init(dev)) == NULL)
+				goto failure;
+			in_dev->cnf.rp_filter = 0;
+
+			if (dev_open(dev))
+				goto failure;
+		}
+	}
+	return dev;
+
+failure:
+	/* allow the register to be completed before unregistering. */
+	rtnl_unlock();
+	rtnl_lock();
+
+	unregister_netdevice(dev);
+	return NULL;
+}
+
+#ifdef CONFIG_IP_PIMSM
+
+static int reg_vif_num = -1;
+
+static int reg_vif_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	read_lock(&mrt_lock);
+	((struct net_device_stats*)dev->priv)->tx_bytes += skb->len;
+	((struct net_device_stats*)dev->priv)->tx_packets++;
+	ipmr_cache_report(skb, reg_vif_num, IGMPMSG_WHOLEPKT);
+	read_unlock(&mrt_lock);
+	kfree_skb(skb);
+	return 0;
+}
+
+static struct net_device_stats *reg_vif_get_stats(struct net_device *dev)
+{
+	return (struct net_device_stats*)dev->priv;
+}
+
+static void reg_vif_setup(struct net_device *dev)
+{
+	dev->type		= ARPHRD_PIMREG;
+	dev->mtu		= 1500 - sizeof(struct iphdr) - 8;
+	dev->flags		= IFF_NOARP;
+	dev->hard_start_xmit	= reg_vif_xmit;
+	dev->get_stats		= reg_vif_get_stats;
+	dev->destructor		= free_netdev;
+}
+
+static struct net_device *ipmr_reg_vif(void)
+{
+	struct net_device *dev;
+	struct in_device *in_dev;
+
+	dev = alloc_netdev(sizeof(struct net_device_stats), "pimreg",
+			   reg_vif_setup);
+
+	if (dev == NULL)
+		return NULL;
+
+	if (register_netdevice(dev)) {
+		free_netdev(dev);
+		return NULL;
+	}
+	dev->iflink = 0;
+
+	if ((in_dev = inetdev_init(dev)) == NULL)
+		goto failure;
+
+	in_dev->cnf.rp_filter = 0;
+
+	if (dev_open(dev))
+		goto failure;
+
+	return dev;
+
+failure:
+	/* allow the register to be completed before unregistering. */
+	rtnl_unlock();
+	rtnl_lock();
+
+	unregister_netdevice(dev);
+	return NULL;
+}
+#endif
+
+/*
+ *	Delete a VIF entry
+ */
+ 
+static int vif_delete(int vifi)
+{
+	struct vif_device *v;
+	struct net_device *dev;
+	struct in_device *in_dev;
+
+	if (vifi < 0 || vifi >= maxvif)
+		return -EADDRNOTAVAIL;
+
+	v = &vif_table[vifi];
+
+	write_lock_bh(&mrt_lock);
+	dev = v->dev;
+	v->dev = NULL;
+
+	if (!dev) {
+		write_unlock_bh(&mrt_lock);
+		return -EADDRNOTAVAIL;
+	}
+
+#ifdef CONFIG_IP_PIMSM
+	if (vifi == reg_vif_num)
+		reg_vif_num = -1;
+#endif
+
+	if (vifi+1 == maxvif) {
+		int tmp;
+		for (tmp=vifi-1; tmp>=0; tmp--) {
+			if (VIF_EXISTS(tmp))
+				break;
+		}
+		maxvif = tmp+1;
+	}
+
+	write_unlock_bh(&mrt_lock);
+
+	dev_set_allmulti(dev, -1);
+
+	if ((in_dev = __in_dev_get(dev)) != NULL) {
+		in_dev->cnf.mc_forwarding--;
+		ip_rt_multicast_event(in_dev);
+	}
+
+	if (v->flags&(VIFF_TUNNEL|VIFF_REGISTER))
+		unregister_netdevice(dev);
+
+	dev_put(dev);
+	return 0;
+}
+
+/* Destroy an unresolved cache entry, killing queued skbs
+   and reporting error to netlink readers.
+ */
+
+static void ipmr_destroy_unres(struct mfc_cache *c)
+{
+	struct sk_buff *skb;
+
+	atomic_dec(&cache_resolve_queue_len);
+
+	while((skb=skb_dequeue(&c->mfc_un.unres.unresolved))) {
+		if (skb->nh.iph->version == 0) {
+			struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct iphdr));
+			nlh->nlmsg_type = NLMSG_ERROR;
+			nlh->nlmsg_len = NLMSG_LENGTH(sizeof(struct nlmsgerr));
+			skb_trim(skb, nlh->nlmsg_len);
+			((struct nlmsgerr*)NLMSG_DATA(nlh))->error = -ETIMEDOUT;
+			netlink_unicast(rtnl, skb, NETLINK_CB(skb).dst_pid, MSG_DONTWAIT);
+		} else
+			kfree_skb(skb);
+	}
+
+	kmem_cache_free(mrt_cachep, c);
+}
+
+
+/* Single timer process for all the unresolved queue. */
+
+static void ipmr_expire_process(unsigned long dummy)
+{
+	unsigned long now;
+	unsigned long expires;
+	struct mfc_cache *c, **cp;
+
+	if (!spin_trylock(&mfc_unres_lock)) {
+		mod_timer(&ipmr_expire_timer, jiffies+HZ/10);
+		return;
+	}
+
+	if (atomic_read(&cache_resolve_queue_len) == 0)
+		goto out;
+
+	now = jiffies;
+	expires = 10*HZ;
+	cp = &mfc_unres_queue;
+
+	while ((c=*cp) != NULL) {
+		if (time_after(c->mfc_un.unres.expires, now)) {
+			unsigned long interval = c->mfc_un.unres.expires - now;
+			if (interval < expires)
+				expires = interval;
+			cp = &c->next;
+			continue;
+		}
+
+		*cp = c->next;
+
+		ipmr_destroy_unres(c);
+	}
+
+	if (atomic_read(&cache_resolve_queue_len))
+		mod_timer(&ipmr_expire_timer, jiffies + expires);
+
+out:
+	spin_unlock(&mfc_unres_lock);
+}
+
+/* Fill oifs list. It is called under write locked mrt_lock. */
+
+static void ipmr_update_threshoulds(struct mfc_cache *cache, unsigned char *ttls)
+{
+	int vifi;
+
+	cache->mfc_un.res.minvif = MAXVIFS;
+	cache->mfc_un.res.maxvif = 0;
+	memset(cache->mfc_un.res.ttls, 255, MAXVIFS);
+
+	for (vifi=0; vifi<maxvif; vifi++) {
+		if (VIF_EXISTS(vifi) && ttls[vifi] && ttls[vifi] < 255) {
+			cache->mfc_un.res.ttls[vifi] = ttls[vifi];
+			if (cache->mfc_un.res.minvif > vifi)
+				cache->mfc_un.res.minvif = vifi;
+			if (cache->mfc_un.res.maxvif <= vifi)
+				cache->mfc_un.res.maxvif = vifi + 1;
+		}
+	}
+}
+
+static int vif_add(struct vifctl *vifc, int mrtsock)
+{
+	int vifi = vifc->vifc_vifi;
+	struct vif_device *v = &vif_table[vifi];
+	struct net_device *dev;
+	struct in_device *in_dev;
+
+	/* Is vif busy ? */
+	if (VIF_EXISTS(vifi))
+		return -EADDRINUSE;
+
+	switch (vifc->vifc_flags) {
+#ifdef CONFIG_IP_PIMSM
+	case VIFF_REGISTER:
+		/*
+		 * Special Purpose VIF in PIM
+		 * All the packets will be sent to the daemon
+		 */
+		if (reg_vif_num >= 0)
+			return -EADDRINUSE;
+		dev = ipmr_reg_vif();
+		if (!dev)
+			return -ENOBUFS;
+		break;
+#endif
+	case VIFF_TUNNEL:	
+		dev = ipmr_new_tunnel(vifc);
+		if (!dev)
+			return -ENOBUFS;
+		break;
+	case 0:
+		dev=ip_dev_find(vifc->vifc_lcl_addr.s_addr);
+		if (!dev)
+			return -EADDRNOTAVAIL;
+		__dev_put(dev);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if ((in_dev = __in_dev_get(dev)) == NULL)
+		return -EADDRNOTAVAIL;
+	in_dev->cnf.mc_forwarding++;
+	dev_set_allmulti(dev, +1);
+	ip_rt_multicast_event(in_dev);
+
+	/*
+	 *	Fill in the VIF structures
+	 */
+	v->rate_limit=vifc->vifc_rate_limit;
+	v->local=vifc->vifc_lcl_addr.s_addr;
+	v->remote=vifc->vifc_rmt_addr.s_addr;
+	v->flags=vifc->vifc_flags;
+	if (!mrtsock)
+		v->flags |= VIFF_STATIC;
+	v->threshold=vifc->vifc_threshold;
+	v->bytes_in = 0;
+	v->bytes_out = 0;
+	v->pkt_in = 0;
+	v->pkt_out = 0;
+	v->link = dev->ifindex;
+	if (v->flags&(VIFF_TUNNEL|VIFF_REGISTER))
+		v->link = dev->iflink;
+
+	/* And finish update writing critical data */
+	write_lock_bh(&mrt_lock);
+	dev_hold(dev);
+	v->dev=dev;
+#ifdef CONFIG_IP_PIMSM
+	if (v->flags&VIFF_REGISTER)
+		reg_vif_num = vifi;
+#endif
+	if (vifi+1 > maxvif)
+		maxvif = vifi+1;
+	write_unlock_bh(&mrt_lock);
+	return 0;
+}
+
+static struct mfc_cache *ipmr_cache_find(__u32 origin, __u32 mcastgrp)
+{
+	int line=MFC_HASH(mcastgrp,origin);
+	struct mfc_cache *c;
+
+	for (c=mfc_cache_array[line]; c; c = c->next) {
+		if (c->mfc_origin==origin && c->mfc_mcastgrp==mcastgrp)
+			break;
+	}
+	return c;
+}
+
+/*
+ *	Allocate a multicast cache entry
+ */
+static struct mfc_cache *ipmr_cache_alloc(void)
+{
+	struct mfc_cache *c=kmem_cache_alloc(mrt_cachep, GFP_KERNEL);
+	if(c==NULL)
+		return NULL;
+	memset(c, 0, sizeof(*c));
+	c->mfc_un.res.minvif = MAXVIFS;
+	return c;
+}
+
+static struct mfc_cache *ipmr_cache_alloc_unres(void)
+{
+	struct mfc_cache *c=kmem_cache_alloc(mrt_cachep, GFP_ATOMIC);
+	if(c==NULL)
+		return NULL;
+	memset(c, 0, sizeof(*c));
+	skb_queue_head_init(&c->mfc_un.unres.unresolved);
+	c->mfc_un.unres.expires = jiffies + 10*HZ;
+	return c;
+}
+
+/*
+ *	A cache entry has gone into a resolved state from queued
+ */
+ 
+static void ipmr_cache_resolve(struct mfc_cache *uc, struct mfc_cache *c)
+{
+	struct sk_buff *skb;
+
+	/*
+	 *	Play the pending entries through our router
+	 */
+
+	while((skb=__skb_dequeue(&uc->mfc_un.unres.unresolved))) {
+		if (skb->nh.iph->version == 0) {
+			int err;
+			struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct iphdr));
+
+			if (ipmr_fill_mroute(skb, c, NLMSG_DATA(nlh)) > 0) {
+				nlh->nlmsg_len = skb->tail - (u8*)nlh;
+			} else {
+				nlh->nlmsg_type = NLMSG_ERROR;
+				nlh->nlmsg_len = NLMSG_LENGTH(sizeof(struct nlmsgerr));
+				skb_trim(skb, nlh->nlmsg_len);
+				((struct nlmsgerr*)NLMSG_DATA(nlh))->error = -EMSGSIZE;
+			}
+			err = netlink_unicast(rtnl, skb, NETLINK_CB(skb).dst_pid, MSG_DONTWAIT);
+		} else
+			ip_mr_forward(skb, c, 0);
+	}
+}
+
+/*
+ *	Bounce a cache query up to mrouted. We could use netlink for this but mrouted
+ *	expects the following bizarre scheme.
+ *
+ *	Called under mrt_lock.
+ */
+ 
+static int ipmr_cache_report(struct sk_buff *pkt, vifi_t vifi, int assert)
+{
+	struct sk_buff *skb;
+	int ihl = pkt->nh.iph->ihl<<2;
+	struct igmphdr *igmp;
+	struct igmpmsg *msg;
+	int ret;
+
+#ifdef CONFIG_IP_PIMSM
+	if (assert == IGMPMSG_WHOLEPKT)
+		skb = skb_realloc_headroom(pkt, sizeof(struct iphdr));
+	else
+#endif
+		skb = alloc_skb(128, GFP_ATOMIC);
+
+	if(!skb)
+		return -ENOBUFS;
+
+#ifdef CONFIG_IP_PIMSM
+	if (assert == IGMPMSG_WHOLEPKT) {
+		/* Ugly, but we have no choice with this interface.
+		   Duplicate old header, fix ihl, length etc.
+		   And all this only to mangle msg->im_msgtype and
+		   to set msg->im_mbz to "mbz" :-)
+		 */
+		msg = (struct igmpmsg*)skb_push(skb, sizeof(struct iphdr));
+		skb->nh.raw = skb->h.raw = (u8*)msg;
+		memcpy(msg, pkt->nh.raw, sizeof(struct iphdr));
+		msg->im_msgtype = IGMPMSG_WHOLEPKT;
+		msg->im_mbz = 0;
+ 		msg->im_vif = reg_vif_num;
+		skb->nh.iph->ihl = sizeof(struct iphdr) >> 2;
+		skb->nh.iph->tot_len = htons(ntohs(pkt->nh.iph->tot_len) + sizeof(struct iphdr));
+	} else 
+#endif
+	{	
+		
+	/*
+	 *	Copy the IP header
+	 */
+
+	skb->nh.iph = (struct iphdr *)skb_put(skb, ihl);
+	memcpy(skb->data,pkt->data,ihl);
+	skb->nh.iph->protocol = 0;			/* Flag to the kernel this is a route add */
+	msg = (struct igmpmsg*)skb->nh.iph;
+	msg->im_vif = vifi;
+	skb->dst = dst_clone(pkt->dst);
+
+	/*
+	 *	Add our header
+	 */
+
+	igmp=(struct igmphdr *)skb_put(skb,sizeof(struct igmphdr));
+	igmp->type	=
+	msg->im_msgtype = assert;
+	igmp->code 	=	0;
+	skb->nh.iph->tot_len=htons(skb->len);			/* Fix the length */
+	skb->h.raw = skb->nh.raw;
+        }
+
+	if (mroute_socket == NULL) {
+		kfree_skb(skb);
+		return -EINVAL;
+	}
+
+	/*
+	 *	Deliver to mrouted
+	 */
+	if ((ret=sock_queue_rcv_skb(mroute_socket,skb))<0) {
+		if (net_ratelimit())
+			printk(KERN_WARNING "mroute: pending queue full, dropping entries.\n");
+		kfree_skb(skb);
+	}
+
+	return ret;
+}
+
+/*
+ *	Queue a packet for resolution. It gets locked cache entry!
+ */
+ 
+static int
+ipmr_cache_unresolved(vifi_t vifi, struct sk_buff *skb)
+{
+	int err;
+	struct mfc_cache *c;
+
+	spin_lock_bh(&mfc_unres_lock);
+	for (c=mfc_unres_queue; c; c=c->next) {
+		if (c->mfc_mcastgrp == skb->nh.iph->daddr &&
+		    c->mfc_origin == skb->nh.iph->saddr)
+			break;
+	}
+
+	if (c == NULL) {
+		/*
+		 *	Create a new entry if allowable
+		 */
+
+		if (atomic_read(&cache_resolve_queue_len)>=10 ||
+		    (c=ipmr_cache_alloc_unres())==NULL) {
+			spin_unlock_bh(&mfc_unres_lock);
+
+			kfree_skb(skb);
+			return -ENOBUFS;
+		}
+
+		/*
+		 *	Fill in the new cache entry
+		 */
+		c->mfc_parent=-1;
+		c->mfc_origin=skb->nh.iph->saddr;
+		c->mfc_mcastgrp=skb->nh.iph->daddr;
+
+		/*
+		 *	Reflect first query at mrouted.
+		 */
+		if ((err = ipmr_cache_report(skb, vifi, IGMPMSG_NOCACHE))<0) {
+			/* If the report failed throw the cache entry 
+			   out - Brad Parker
+			 */
+			spin_unlock_bh(&mfc_unres_lock);
+
+			kmem_cache_free(mrt_cachep, c);
+			kfree_skb(skb);
+			return err;
+		}
+
+		atomic_inc(&cache_resolve_queue_len);
+		c->next = mfc_unres_queue;
+		mfc_unres_queue = c;
+
+		mod_timer(&ipmr_expire_timer, c->mfc_un.unres.expires);
+	}
+
+	/*
+	 *	See if we can append the packet
+	 */
+	if (c->mfc_un.unres.unresolved.qlen>3) {
+		kfree_skb(skb);
+		err = -ENOBUFS;
+	} else {
+		skb_queue_tail(&c->mfc_un.unres.unresolved,skb);
+		err = 0;
+	}
+
+	spin_unlock_bh(&mfc_unres_lock);
+	return err;
+}
+
+/*
+ *	MFC cache manipulation by user space mroute daemon
+ */
+
+static int ipmr_mfc_delete(struct mfcctl *mfc)
+{
+	int line;
+	struct mfc_cache *c, **cp;
+
+	line=MFC_HASH(mfc->mfcc_mcastgrp.s_addr, mfc->mfcc_origin.s_addr);
+
+	for (cp=&mfc_cache_array[line]; (c=*cp) != NULL; cp = &c->next) {
+		if (c->mfc_origin == mfc->mfcc_origin.s_addr &&
+		    c->mfc_mcastgrp == mfc->mfcc_mcastgrp.s_addr) {
+			write_lock_bh(&mrt_lock);
+			*cp = c->next;
+			write_unlock_bh(&mrt_lock);
+
+			kmem_cache_free(mrt_cachep, c);
+			return 0;
+		}
+	}
+	return -ENOENT;
+}
+
+static int ipmr_mfc_add(struct mfcctl *mfc, int mrtsock)
+{
+	int line;
+	struct mfc_cache *uc, *c, **cp;
+
+	line=MFC_HASH(mfc->mfcc_mcastgrp.s_addr, mfc->mfcc_origin.s_addr);
+
+	for (cp=&mfc_cache_array[line]; (c=*cp) != NULL; cp = &c->next) {
+		if (c->mfc_origin == mfc->mfcc_origin.s_addr &&
+		    c->mfc_mcastgrp == mfc->mfcc_mcastgrp.s_addr)
+			break;
+	}
+
+	if (c != NULL) {
+		write_lock_bh(&mrt_lock);
+		c->mfc_parent = mfc->mfcc_parent;
+		ipmr_update_threshoulds(c, mfc->mfcc_ttls);
+		if (!mrtsock)
+			c->mfc_flags |= MFC_STATIC;
+		write_unlock_bh(&mrt_lock);
+		return 0;
+	}
+
+	if(!MULTICAST(mfc->mfcc_mcastgrp.s_addr))
+		return -EINVAL;
+
+	c=ipmr_cache_alloc();
+	if (c==NULL)
+		return -ENOMEM;
+
+	c->mfc_origin=mfc->mfcc_origin.s_addr;
+	c->mfc_mcastgrp=mfc->mfcc_mcastgrp.s_addr;
+	c->mfc_parent=mfc->mfcc_parent;
+	ipmr_update_threshoulds(c, mfc->mfcc_ttls);
+	if (!mrtsock)
+		c->mfc_flags |= MFC_STATIC;
+
+	write_lock_bh(&mrt_lock);
+	c->next = mfc_cache_array[line];
+	mfc_cache_array[line] = c;
+	write_unlock_bh(&mrt_lock);
+
+	/*
+	 *	Check to see if we resolved a queued list. If so we
+	 *	need to send on the frames and tidy up.
+	 */
+	spin_lock_bh(&mfc_unres_lock);
+	for (cp = &mfc_unres_queue; (uc=*cp) != NULL;
+	     cp = &uc->next) {
+		if (uc->mfc_origin == c->mfc_origin &&
+		    uc->mfc_mcastgrp == c->mfc_mcastgrp) {
+			*cp = uc->next;
+			if (atomic_dec_and_test(&cache_resolve_queue_len))
+				del_timer(&ipmr_expire_timer);
+			break;
+		}
+	}
+	spin_unlock_bh(&mfc_unres_lock);
+
+	if (uc) {
+		ipmr_cache_resolve(uc, c);
+		kmem_cache_free(mrt_cachep, uc);
+	}
+	return 0;
+}
+
+/*
+ *	Close the multicast socket, and clear the vif tables etc
+ */
+ 
+static void mroute_clean_tables(struct sock *sk)
+{
+	int i;
+		
+	/*
+	 *	Shut down all active vif entries
+	 */
+	for(i=0; i<maxvif; i++) {
+		if (!(vif_table[i].flags&VIFF_STATIC))
+			vif_delete(i);
+	}
+
+	/*
+	 *	Wipe the cache
+	 */
+	for (i=0;i<MFC_LINES;i++) {
+		struct mfc_cache *c, **cp;
+
+		cp = &mfc_cache_array[i];
+		while ((c = *cp) != NULL) {
+			if (c->mfc_flags&MFC_STATIC) {
+				cp = &c->next;
+				continue;
+			}
+			write_lock_bh(&mrt_lock);
+			*cp = c->next;
+			write_unlock_bh(&mrt_lock);
+
+			kmem_cache_free(mrt_cachep, c);
+		}
+	}
+
+	if (atomic_read(&cache_resolve_queue_len) != 0) {
+		struct mfc_cache *c;
+
+		spin_lock_bh(&mfc_unres_lock);
+		while (mfc_unres_queue != NULL) {
+			c = mfc_unres_queue;
+			mfc_unres_queue = c->next;
+			spin_unlock_bh(&mfc_unres_lock);
+
+			ipmr_destroy_unres(c);
+
+			spin_lock_bh(&mfc_unres_lock);
+		}
+		spin_unlock_bh(&mfc_unres_lock);
+	}
+}
+
+static void mrtsock_destruct(struct sock *sk)
+{
+	rtnl_lock();
+	if (sk == mroute_socket) {
+		ipv4_devconf.mc_forwarding--;
+
+		write_lock_bh(&mrt_lock);
+		mroute_socket=NULL;
+		write_unlock_bh(&mrt_lock);
+
+		mroute_clean_tables(sk);
+	}
+	rtnl_unlock();
+}
+
+/*
+ *	Socket options and virtual interface manipulation. The whole
+ *	virtual interface system is a complete heap, but unfortunately
+ *	that's how BSD mrouted happens to think. Maybe one day with a proper
+ *	MOSPF/PIM router set up we can clean this up.
+ */
+ 
+int ip_mroute_setsockopt(struct sock *sk,int optname,char __user *optval,int optlen)
+{
+	int ret;
+	struct vifctl vif;
+	struct mfcctl mfc;
+	
+	if(optname!=MRT_INIT)
+	{
+		if(sk!=mroute_socket && !capable(CAP_NET_ADMIN))
+			return -EACCES;
+	}
+
+	switch(optname)
+	{
+		case MRT_INIT:
+			if (sk->sk_type != SOCK_RAW ||
+			    inet_sk(sk)->num != IPPROTO_IGMP)
+				return -EOPNOTSUPP;
+			if(optlen!=sizeof(int))
+				return -ENOPROTOOPT;
+
+			rtnl_lock();
+			if (mroute_socket) {
+				rtnl_unlock();
+				return -EADDRINUSE;
+			}
+
+			ret = ip_ra_control(sk, 1, mrtsock_destruct);
+			if (ret == 0) {
+				write_lock_bh(&mrt_lock);
+				mroute_socket=sk;
+				write_unlock_bh(&mrt_lock);
+
+				ipv4_devconf.mc_forwarding++;
+			}
+			rtnl_unlock();
+			return ret;
+		case MRT_DONE:
+			if (sk!=mroute_socket)
+				return -EACCES;
+			return ip_ra_control(sk, 0, NULL);
+		case MRT_ADD_VIF:
+		case MRT_DEL_VIF:
+			if(optlen!=sizeof(vif))
+				return -EINVAL;
+			if (copy_from_user(&vif,optval,sizeof(vif)))
+				return -EFAULT; 
+			if(vif.vifc_vifi >= MAXVIFS)
+				return -ENFILE;
+			rtnl_lock();
+			if (optname==MRT_ADD_VIF) {
+				ret = vif_add(&vif, sk==mroute_socket);
+			} else {
+				ret = vif_delete(vif.vifc_vifi);
+			}
+			rtnl_unlock();
+			return ret;
+
+		/*
+		 *	Manipulate the forwarding caches. These live
+		 *	in a sort of kernel/user symbiosis.
+		 */
+		case MRT_ADD_MFC:
+		case MRT_DEL_MFC:
+			if(optlen!=sizeof(mfc))
+				return -EINVAL;
+			if (copy_from_user(&mfc,optval, sizeof(mfc)))
+				return -EFAULT;
+			rtnl_lock();
+			if (optname==MRT_DEL_MFC)
+				ret = ipmr_mfc_delete(&mfc);
+			else
+				ret = ipmr_mfc_add(&mfc, sk==mroute_socket);
+			rtnl_unlock();
+			return ret;
+		/*
+		 *	Control PIM assert.
+		 */
+		case MRT_ASSERT:
+		{
+			int v;
+			if(get_user(v,(int __user *)optval))
+				return -EFAULT;
+			mroute_do_assert=(v)?1:0;
+			return 0;
+		}
+#ifdef CONFIG_IP_PIMSM
+		case MRT_PIM:
+		{
+			int v, ret;
+			if(get_user(v,(int __user *)optval))
+				return -EFAULT;
+			v = (v)?1:0;
+			rtnl_lock();
+			ret = 0;
+			if (v != mroute_do_pim) {
+				mroute_do_pim = v;
+				mroute_do_assert = v;
+#ifdef CONFIG_IP_PIMSM_V2
+				if (mroute_do_pim)
+					ret = inet_add_protocol(&pim_protocol,
+								IPPROTO_PIM);
+				else
+					ret = inet_del_protocol(&pim_protocol,
+								IPPROTO_PIM);
+				if (ret < 0)
+					ret = -EAGAIN;
+#endif
+			}
+			rtnl_unlock();
+			return ret;
+		}
+#endif
+		/*
+		 *	Spurious command, or MRT_VERSION which you cannot
+		 *	set.
+		 */
+		default:
+			return -ENOPROTOOPT;
+	}
+}
+
+/*
+ *	Getsock opt support for the multicast routing system.
+ */
+ 
+int ip_mroute_getsockopt(struct sock *sk,int optname,char __user *optval,int __user *optlen)
+{
+	int olr;
+	int val;
+
+	if(optname!=MRT_VERSION && 
+#ifdef CONFIG_IP_PIMSM
+	   optname!=MRT_PIM &&
+#endif
+	   optname!=MRT_ASSERT)
+		return -ENOPROTOOPT;
+
+	if (get_user(olr, optlen))
+		return -EFAULT;
+
+	olr = min_t(unsigned int, olr, sizeof(int));
+	if (olr < 0)
+		return -EINVAL;
+		
+	if(put_user(olr,optlen))
+		return -EFAULT;
+	if(optname==MRT_VERSION)
+		val=0x0305;
+#ifdef CONFIG_IP_PIMSM
+	else if(optname==MRT_PIM)
+		val=mroute_do_pim;
+#endif
+	else
+		val=mroute_do_assert;
+	if(copy_to_user(optval,&val,olr))
+		return -EFAULT;
+	return 0;
+}
+
+/*
+ *	The IP multicast ioctl support routines.
+ */
+ 
+int ipmr_ioctl(struct sock *sk, int cmd, void __user *arg)
+{
+	struct sioc_sg_req sr;
+	struct sioc_vif_req vr;
+	struct vif_device *vif;
+	struct mfc_cache *c;
+	
+	switch(cmd)
+	{
+		case SIOCGETVIFCNT:
+			if (copy_from_user(&vr,arg,sizeof(vr)))
+				return -EFAULT; 
+			if(vr.vifi>=maxvif)
+				return -EINVAL;
+			read_lock(&mrt_lock);
+			vif=&vif_table[vr.vifi];
+			if(VIF_EXISTS(vr.vifi))	{
+				vr.icount=vif->pkt_in;
+				vr.ocount=vif->pkt_out;
+				vr.ibytes=vif->bytes_in;
+				vr.obytes=vif->bytes_out;
+				read_unlock(&mrt_lock);
+
+				if (copy_to_user(arg,&vr,sizeof(vr)))
+					return -EFAULT;
+				return 0;
+			}
+			read_unlock(&mrt_lock);
+			return -EADDRNOTAVAIL;
+		case SIOCGETSGCNT:
+			if (copy_from_user(&sr,arg,sizeof(sr)))
+				return -EFAULT;
+
+			read_lock(&mrt_lock);
+			c = ipmr_cache_find(sr.src.s_addr, sr.grp.s_addr);
+			if (c) {
+				sr.pktcnt = c->mfc_un.res.pkt;
+				sr.bytecnt = c->mfc_un.res.bytes;
+				sr.wrong_if = c->mfc_un.res.wrong_if;
+				read_unlock(&mrt_lock);
+
+				if (copy_to_user(arg,&sr,sizeof(sr)))
+					return -EFAULT;
+				return 0;
+			}
+			read_unlock(&mrt_lock);
+			return -EADDRNOTAVAIL;
+		default:
+			return -ENOIOCTLCMD;
+	}
+}
+
+
+static int ipmr_device_event(struct notifier_block *this, unsigned long event, void *ptr)
+{
+	struct vif_device *v;
+	int ct;
+	if (event != NETDEV_UNREGISTER)
+		return NOTIFY_DONE;
+	v=&vif_table[0];
+	for(ct=0;ct<maxvif;ct++,v++) {
+		if (v->dev==ptr)
+			vif_delete(ct);
+	}
+	return NOTIFY_DONE;
+}
+
+
+static struct notifier_block ip_mr_notifier={
+	.notifier_call = ipmr_device_event,
+};
+
+/*
+ * 	Encapsulate a packet by attaching a valid IPIP header to it.
+ *	This avoids tunnel drivers and other mess and gives us the speed so
+ *	important for multicast video.
+ */
+ 
+static void ip_encap(struct sk_buff *skb, u32 saddr, u32 daddr)
+{
+	struct iphdr *iph = (struct iphdr *)skb_push(skb,sizeof(struct iphdr));
+
+	iph->version	= 	4;
+	iph->tos	=	skb->nh.iph->tos;
+	iph->ttl	=	skb->nh.iph->ttl;
+	iph->frag_off	=	0;
+	iph->daddr	=	daddr;
+	iph->saddr	=	saddr;
+	iph->protocol	=	IPPROTO_IPIP;
+	iph->ihl	=	5;
+	iph->tot_len	=	htons(skb->len);
+	ip_select_ident(iph, skb->dst, NULL);
+	ip_send_check(iph);
+
+	skb->h.ipiph = skb->nh.iph;
+	skb->nh.iph = iph;
+	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
+	nf_reset(skb);
+}
+
+static inline int ipmr_forward_finish(struct sk_buff *skb)
+{
+	struct ip_options * opt	= &(IPCB(skb)->opt);
+
+	IP_INC_STATS_BH(IPSTATS_MIB_OUTFORWDATAGRAMS);
+
+	if (unlikely(opt->optlen))
+		ip_forward_options(skb);
+
+	return dst_output(skb);
+}
+
+/*
+ *	Processing handlers for ipmr_forward
+ */
+
+static void ipmr_queue_xmit(struct sk_buff *skb, struct mfc_cache *c, int vifi)
+{
+	struct iphdr *iph = skb->nh.iph;
+	struct vif_device *vif = &vif_table[vifi];
+	struct net_device *dev;
+	struct rtable *rt;
+	int    encap = 0;
+
+	if (vif->dev == NULL)
+		goto out_free;
+
+#ifdef CONFIG_IP_PIMSM
+	if (vif->flags & VIFF_REGISTER) {
+		vif->pkt_out++;
+		vif->bytes_out+=skb->len;
+		((struct net_device_stats*)vif->dev->priv)->tx_bytes += skb->len;
+		((struct net_device_stats*)vif->dev->priv)->tx_packets++;
+		ipmr_cache_report(skb, vifi, IGMPMSG_WHOLEPKT);
+		kfree_skb(skb);
+		return;
+	}
+#endif
+
+	if (vif->flags&VIFF_TUNNEL) {
+		struct flowi fl = { .oif = vif->link,
+				    .nl_u = { .ip4_u =
+					      { .daddr = vif->remote,
+						.saddr = vif->local,
+						.tos = RT_TOS(iph->tos) } },
+				    .proto = IPPROTO_IPIP };
+		if (ip_route_output_key(&rt, &fl))
+			goto out_free;
+		encap = sizeof(struct iphdr);
+	} else {
+		struct flowi fl = { .oif = vif->link,
+				    .nl_u = { .ip4_u =
+					      { .daddr = iph->daddr,
+						.tos = RT_TOS(iph->tos) } },
+				    .proto = IPPROTO_IPIP };
+		if (ip_route_output_key(&rt, &fl))
+			goto out_free;
+	}
+
+	dev = rt->u.dst.dev;
+
+	if (skb->len+encap > dst_mtu(&rt->u.dst) && (ntohs(iph->frag_off) & IP_DF)) {
+		/* Do not fragment multicasts. Alas, IPv4 does not
+		   allow to send ICMP, so that packets will disappear
+		   to blackhole.
+		 */
+
+		IP_INC_STATS_BH(IPSTATS_MIB_FRAGFAILS);
+		ip_rt_put(rt);
+		goto out_free;
+	}
+
+	encap += LL_RESERVED_SPACE(dev) + rt->u.dst.header_len;
+
+	if (skb_cow(skb, encap)) {
+ 		ip_rt_put(rt);
+		goto out_free;
+	}
+
+	vif->pkt_out++;
+	vif->bytes_out+=skb->len;
+
+	dst_release(skb->dst);
+	skb->dst = &rt->u.dst;
+	iph = skb->nh.iph;
+	ip_decrease_ttl(iph);
+
+	/* FIXME: forward and output firewalls used to be called here.
+	 * What do we do with netfilter? -- RR */
+	if (vif->flags & VIFF_TUNNEL) {
+		ip_encap(skb, vif->local, vif->remote);
+		/* FIXME: extra output firewall step used to be here. --RR */
+		((struct ip_tunnel *)vif->dev->priv)->stat.tx_packets++;
+		((struct ip_tunnel *)vif->dev->priv)->stat.tx_bytes+=skb->len;
+	}
+
+	IPCB(skb)->flags |= IPSKB_FORWARDED;
+
+	/*
+	 * RFC1584 teaches, that DVMRP/PIM router must deliver packets locally
+	 * not only before forwarding, but after forwarding on all output
+	 * interfaces. It is clear, if mrouter runs a multicasting
+	 * program, it should receive packets not depending to what interface
+	 * program is joined.
+	 * If we will not make it, the program will have to join on all
+	 * interfaces. On the other hand, multihoming host (or router, but
+	 * not mrouter) cannot join to more than one interface - it will
+	 * result in receiving multiple packets.
+	 */
+	NF_HOOK(PF_INET, NF_IP_FORWARD, skb, skb->dev, dev, 
+		ipmr_forward_finish);
+	return;
+
+out_free:
+	kfree_skb(skb);
+	return;
+}
+
+static int ipmr_find_vif(struct net_device *dev)
+{
+	int ct;
+	for (ct=maxvif-1; ct>=0; ct--) {
+		if (vif_table[ct].dev == dev)
+			break;
+	}
+	return ct;
+}
+
+/* "local" means that we should preserve one skb (for local delivery) */
+
+static int ip_mr_forward(struct sk_buff *skb, struct mfc_cache *cache, int local)
+{
+	int psend = -1;
+	int vif, ct;
+
+	vif = cache->mfc_parent;
+	cache->mfc_un.res.pkt++;
+	cache->mfc_un.res.bytes += skb->len;
+
+	/*
+	 * Wrong interface: drop packet and (maybe) send PIM assert.
+	 */
+	if (vif_table[vif].dev != skb->dev) {
+		int true_vifi;
+
+		if (((struct rtable*)skb->dst)->fl.iif == 0) {
+			/* It is our own packet, looped back.
+			   Very complicated situation...
+
+			   The best workaround until routing daemons will be
+			   fixed is not to redistribute packet, if it was
+			   send through wrong interface. It means, that
+			   multicast applications WILL NOT work for
+			   (S,G), which have default multicast route pointing
+			   to wrong oif. In any case, it is not a good
+			   idea to use multicasting applications on router.
+			 */
+			goto dont_forward;
+		}
+
+		cache->mfc_un.res.wrong_if++;
+		true_vifi = ipmr_find_vif(skb->dev);
+
+		if (true_vifi >= 0 && mroute_do_assert &&
+		    /* pimsm uses asserts, when switching from RPT to SPT,
+		       so that we cannot check that packet arrived on an oif.
+		       It is bad, but otherwise we would need to move pretty
+		       large chunk of pimd to kernel. Ough... --ANK
+		     */
+		    (mroute_do_pim || cache->mfc_un.res.ttls[true_vifi] < 255) &&
+		    time_after(jiffies, 
+			       cache->mfc_un.res.last_assert + MFC_ASSERT_THRESH)) {
+			cache->mfc_un.res.last_assert = jiffies;
+			ipmr_cache_report(skb, true_vifi, IGMPMSG_WRONGVIF);
+		}
+		goto dont_forward;
+	}
+
+	vif_table[vif].pkt_in++;
+	vif_table[vif].bytes_in+=skb->len;
+
+	/*
+	 *	Forward the frame
+	 */
+	for (ct = cache->mfc_un.res.maxvif-1; ct >= cache->mfc_un.res.minvif; ct--) {
+		if (skb->nh.iph->ttl > cache->mfc_un.res.ttls[ct]) {
+			if (psend != -1) {
+				struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
+				if (skb2)
+					ipmr_queue_xmit(skb2, cache, psend);
+			}
+			psend=ct;
+		}
+	}
+	if (psend != -1) {
+		if (local) {
+			struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
+			if (skb2)
+				ipmr_queue_xmit(skb2, cache, psend);
+		} else {
+			ipmr_queue_xmit(skb, cache, psend);
+			return 0;
+		}
+	}
+
+dont_forward:
+	if (!local)
+		kfree_skb(skb);
+	return 0;
+}
+
+
+/*
+ *	Multicast packets for forwarding arrive here
+ */
+
+int ip_mr_input(struct sk_buff *skb)
+{
+	struct mfc_cache *cache;
+	int local = ((struct rtable*)skb->dst)->rt_flags&RTCF_LOCAL;
+
+	/* Packet is looped back after forward, it should not be
+	   forwarded second time, but still can be delivered locally.
+	 */
+	if (IPCB(skb)->flags&IPSKB_FORWARDED)
+		goto dont_forward;
+
+	if (!local) {
+		    if (IPCB(skb)->opt.router_alert) {
+			    if (ip_call_ra_chain(skb))
+				    return 0;
+		    } else if (skb->nh.iph->protocol == IPPROTO_IGMP){
+			    /* IGMPv1 (and broken IGMPv2 implementations sort of
+			       Cisco IOS <= 11.2(8)) do not put router alert
+			       option to IGMP packets destined to routable
+			       groups. It is very bad, because it means
+			       that we can forward NO IGMP messages.
+			     */
+			    read_lock(&mrt_lock);
+			    if (mroute_socket) {
+				    raw_rcv(mroute_socket, skb);
+				    read_unlock(&mrt_lock);
+				    return 0;
+			    }
+			    read_unlock(&mrt_lock);
+		    }
+	}
+
+	read_lock(&mrt_lock);
+	cache = ipmr_cache_find(skb->nh.iph->saddr, skb->nh.iph->daddr);
+
+	/*
+	 *	No usable cache entry
+	 */
+	if (cache==NULL) {
+		int vif;
+
+		if (local) {
+			struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
+			ip_local_deliver(skb);
+			if (skb2 == NULL) {
+				read_unlock(&mrt_lock);
+				return -ENOBUFS;
+			}
+			skb = skb2;
+		}
+
+		vif = ipmr_find_vif(skb->dev);
+		if (vif >= 0) {
+			int err = ipmr_cache_unresolved(vif, skb);
+			read_unlock(&mrt_lock);
+
+			return err;
+		}
+		read_unlock(&mrt_lock);
+		kfree_skb(skb);
+		return -ENODEV;
+	}
+
+	ip_mr_forward(skb, cache, local);
+
+	read_unlock(&mrt_lock);
+
+	if (local)
+		return ip_local_deliver(skb);
+
+	return 0;
+
+dont_forward:
+	if (local)
+		return ip_local_deliver(skb);
+	kfree_skb(skb);
+	return 0;
+}
+
+#ifdef CONFIG_IP_PIMSM_V1
+/*
+ * Handle IGMP messages of PIMv1
+ */
+
+int pim_rcv_v1(struct sk_buff * skb)
+{
+	struct igmphdr *pim;
+	struct iphdr   *encap;
+	struct net_device  *reg_dev = NULL;
+
+	if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(*encap))) 
+		goto drop;
+
+	pim = (struct igmphdr*)skb->h.raw;
+
+        if (!mroute_do_pim ||
+	    skb->len < sizeof(*pim) + sizeof(*encap) ||
+	    pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER) 
+		goto drop;
+
+	encap = (struct iphdr*)(skb->h.raw + sizeof(struct igmphdr));
+	/*
+	   Check that:
+	   a. packet is really destinted to a multicast group
+	   b. packet is not a NULL-REGISTER
+	   c. packet is not truncated
+	 */
+	if (!MULTICAST(encap->daddr) ||
+	    encap->tot_len == 0 ||
+	    ntohs(encap->tot_len) + sizeof(*pim) > skb->len) 
+		goto drop;
+
+	read_lock(&mrt_lock);
+	if (reg_vif_num >= 0)
+		reg_dev = vif_table[reg_vif_num].dev;
+	if (reg_dev)
+		dev_hold(reg_dev);
+	read_unlock(&mrt_lock);
+
+	if (reg_dev == NULL) 
+		goto drop;
+
+	skb->mac.raw = skb->nh.raw;
+	skb_pull(skb, (u8*)encap - skb->data);
+	skb->nh.iph = (struct iphdr *)skb->data;
+	skb->dev = reg_dev;
+	memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
+	skb->protocol = htons(ETH_P_IP);
+	skb->ip_summed = 0;
+	skb->pkt_type = PACKET_HOST;
+	dst_release(skb->dst);
+	skb->dst = NULL;
+	((struct net_device_stats*)reg_dev->priv)->rx_bytes += skb->len;
+	((struct net_device_stats*)reg_dev->priv)->rx_packets++;
+	nf_reset(skb);
+	netif_rx(skb);
+	dev_put(reg_dev);
+	return 0;
+ drop:
+	kfree_skb(skb);
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_IP_PIMSM_V2
+static int pim_rcv(struct sk_buff * skb)
+{
+	struct pimreghdr *pim;
+	struct iphdr   *encap;
+	struct net_device  *reg_dev = NULL;
+
+	if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(*encap))) 
+		goto drop;
+
+	pim = (struct pimreghdr*)skb->h.raw;
+        if (pim->type != ((PIM_VERSION<<4)|(PIM_REGISTER)) ||
+	    (pim->flags&PIM_NULL_REGISTER) ||
+	    (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 && 
+	     (u16)csum_fold(skb_checksum(skb, 0, skb->len, 0)))) 
+		goto drop;
+
+	/* check if the inner packet is destined to mcast group */
+	encap = (struct iphdr*)(skb->h.raw + sizeof(struct pimreghdr));
+	if (!MULTICAST(encap->daddr) ||
+	    encap->tot_len == 0 ||
+	    ntohs(encap->tot_len) + sizeof(*pim) > skb->len) 
+		goto drop;
+
+	read_lock(&mrt_lock);
+	if (reg_vif_num >= 0)
+		reg_dev = vif_table[reg_vif_num].dev;
+	if (reg_dev)
+		dev_hold(reg_dev);
+	read_unlock(&mrt_lock);
+
+	if (reg_dev == NULL) 
+		goto drop;
+
+	skb->mac.raw = skb->nh.raw;
+	skb_pull(skb, (u8*)encap - skb->data);
+	skb->nh.iph = (struct iphdr *)skb->data;
+	skb->dev = reg_dev;
+	memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
+	skb->protocol = htons(ETH_P_IP);
+	skb->ip_summed = 0;
+	skb->pkt_type = PACKET_HOST;
+	dst_release(skb->dst);
+	((struct net_device_stats*)reg_dev->priv)->rx_bytes += skb->len;
+	((struct net_device_stats*)reg_dev->priv)->rx_packets++;
+	skb->dst = NULL;
+	nf_reset(skb);
+	netif_rx(skb);
+	dev_put(reg_dev);
+	return 0;
+ drop:
+	kfree_skb(skb);
+	return 0;
+}
+#endif
+
+static int
+ipmr_fill_mroute(struct sk_buff *skb, struct mfc_cache *c, struct rtmsg *rtm)
+{
+	int ct;
+	struct rtnexthop *nhp;
+	struct net_device *dev = vif_table[c->mfc_parent].dev;
+	u8 *b = skb->tail;
+	struct rtattr *mp_head;
+
+	if (dev)
+		RTA_PUT(skb, RTA_IIF, 4, &dev->ifindex);
+
+	mp_head = (struct rtattr*)skb_put(skb, RTA_LENGTH(0));
+
+	for (ct = c->mfc_un.res.minvif; ct < c->mfc_un.res.maxvif; ct++) {
+		if (c->mfc_un.res.ttls[ct] < 255) {
+			if (skb_tailroom(skb) < RTA_ALIGN(RTA_ALIGN(sizeof(*nhp)) + 4))
+				goto rtattr_failure;
+			nhp = (struct rtnexthop*)skb_put(skb, RTA_ALIGN(sizeof(*nhp)));
+			nhp->rtnh_flags = 0;
+			nhp->rtnh_hops = c->mfc_un.res.ttls[ct];
+			nhp->rtnh_ifindex = vif_table[ct].dev->ifindex;
+			nhp->rtnh_len = sizeof(*nhp);
+		}
+	}
+	mp_head->rta_type = RTA_MULTIPATH;
+	mp_head->rta_len = skb->tail - (u8*)mp_head;
+	rtm->rtm_type = RTN_MULTICAST;
+	return 1;
+
+rtattr_failure:
+	skb_trim(skb, b - skb->data);
+	return -EMSGSIZE;
+}
+
+int ipmr_get_route(struct sk_buff *skb, struct rtmsg *rtm, int nowait)
+{
+	int err;
+	struct mfc_cache *cache;
+	struct rtable *rt = (struct rtable*)skb->dst;
+
+	read_lock(&mrt_lock);
+	cache = ipmr_cache_find(rt->rt_src, rt->rt_dst);
+
+	if (cache==NULL) {
+		struct net_device *dev;
+		int vif;
+
+		if (nowait) {
+			read_unlock(&mrt_lock);
+			return -EAGAIN;
+		}
+
+		dev = skb->dev;
+		if (dev == NULL || (vif = ipmr_find_vif(dev)) < 0) {
+			read_unlock(&mrt_lock);
+			return -ENODEV;
+		}
+		skb->nh.raw = skb_push(skb, sizeof(struct iphdr));
+		skb->nh.iph->ihl = sizeof(struct iphdr)>>2;
+		skb->nh.iph->saddr = rt->rt_src;
+		skb->nh.iph->daddr = rt->rt_dst;
+		skb->nh.iph->version = 0;
+		err = ipmr_cache_unresolved(vif, skb);
+		read_unlock(&mrt_lock);
+		return err;
+	}
+
+	if (!nowait && (rtm->rtm_flags&RTM_F_NOTIFY))
+		cache->mfc_flags |= MFC_NOTIFY;
+	err = ipmr_fill_mroute(skb, cache, rtm);
+	read_unlock(&mrt_lock);
+	return err;
+}
+
+#ifdef CONFIG_PROC_FS	
+/*
+ *	The /proc interfaces to multicast routing /proc/ip_mr_cache /proc/ip_mr_vif
+ */
+struct ipmr_vif_iter {
+	int ct;
+};
+
+static struct vif_device *ipmr_vif_seq_idx(struct ipmr_vif_iter *iter,
+					   loff_t pos)
+{
+	for (iter->ct = 0; iter->ct < maxvif; ++iter->ct) {
+		if(!VIF_EXISTS(iter->ct))
+			continue;
+		if (pos-- == 0) 
+			return &vif_table[iter->ct];
+	}
+	return NULL;
+}
+
+static void *ipmr_vif_seq_start(struct seq_file *seq, loff_t *pos)
+{
+	read_lock(&mrt_lock);
+	return *pos ? ipmr_vif_seq_idx(seq->private, *pos - 1) 
+		: SEQ_START_TOKEN;
+}
+
+static void *ipmr_vif_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	struct ipmr_vif_iter *iter = seq->private;
+
+	++*pos;
+	if (v == SEQ_START_TOKEN)
+		return ipmr_vif_seq_idx(iter, 0);
+	
+	while (++iter->ct < maxvif) {
+		if(!VIF_EXISTS(iter->ct))
+			continue;
+		return &vif_table[iter->ct];
+	}
+	return NULL;
+}
+
+static void ipmr_vif_seq_stop(struct seq_file *seq, void *v)
+{
+	read_unlock(&mrt_lock);
+}
+
+static int ipmr_vif_seq_show(struct seq_file *seq, void *v)
+{
+	if (v == SEQ_START_TOKEN) {
+		seq_puts(seq, 
+			 "Interface      BytesIn  PktsIn  BytesOut PktsOut Flags Local    Remote\n");
+	} else {
+		const struct vif_device *vif = v;
+		const char *name =  vif->dev ? vif->dev->name : "none";
+
+		seq_printf(seq,
+			   "%2Zd %-10s %8ld %7ld  %8ld %7ld %05X %08X %08X\n",
+			   vif - vif_table,
+			   name, vif->bytes_in, vif->pkt_in, 
+			   vif->bytes_out, vif->pkt_out,
+			   vif->flags, vif->local, vif->remote);
+	}
+	return 0;
+}
+
+static struct seq_operations ipmr_vif_seq_ops = {
+	.start = ipmr_vif_seq_start,
+	.next  = ipmr_vif_seq_next,
+	.stop  = ipmr_vif_seq_stop,
+	.show  = ipmr_vif_seq_show,
+};
+
+static int ipmr_vif_open(struct inode *inode, struct file *file)
+{
+	struct seq_file *seq;
+	int rc = -ENOMEM;
+	struct ipmr_vif_iter *s = kmalloc(sizeof(*s), GFP_KERNEL);
+       
+	if (!s)
+		goto out;
+
+	rc = seq_open(file, &ipmr_vif_seq_ops);
+	if (rc)
+		goto out_kfree;
+
+	s->ct = 0;
+	seq = file->private_data;
+	seq->private = s;
+out:
+	return rc;
+out_kfree:
+	kfree(s);
+	goto out;
+
+}
+
+static struct file_operations ipmr_vif_fops = {
+	.owner	 = THIS_MODULE,
+	.open    = ipmr_vif_open,
+	.read    = seq_read,
+	.llseek  = seq_lseek,
+	.release = seq_release_private,
+};
+
+struct ipmr_mfc_iter {
+	struct mfc_cache **cache;
+	int ct;
+};
+
+
+static struct mfc_cache *ipmr_mfc_seq_idx(struct ipmr_mfc_iter *it, loff_t pos)
+{
+	struct mfc_cache *mfc;
+
+	it->cache = mfc_cache_array;
+	read_lock(&mrt_lock);
+	for (it->ct = 0; it->ct < MFC_LINES; it->ct++) 
+		for(mfc = mfc_cache_array[it->ct]; mfc; mfc = mfc->next) 
+			if (pos-- == 0) 
+				return mfc;
+	read_unlock(&mrt_lock);
+
+	it->cache = &mfc_unres_queue;
+	spin_lock_bh(&mfc_unres_lock);
+	for(mfc = mfc_unres_queue; mfc; mfc = mfc->next) 
+		if (pos-- == 0)
+			return mfc;
+	spin_unlock_bh(&mfc_unres_lock);
+
+	it->cache = NULL;
+	return NULL;
+}
+
+
+static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos)
+{
+	struct ipmr_mfc_iter *it = seq->private;
+	it->cache = NULL;
+	it->ct = 0;
+	return *pos ? ipmr_mfc_seq_idx(seq->private, *pos - 1) 
+		: SEQ_START_TOKEN;
+}
+
+static void *ipmr_mfc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	struct mfc_cache *mfc = v;
+	struct ipmr_mfc_iter *it = seq->private;
+
+	++*pos;
+
+	if (v == SEQ_START_TOKEN)
+		return ipmr_mfc_seq_idx(seq->private, 0);
+
+	if (mfc->next)
+		return mfc->next;
+	
+	if (it->cache == &mfc_unres_queue) 
+		goto end_of_list;
+
+	BUG_ON(it->cache != mfc_cache_array);
+
+	while (++it->ct < MFC_LINES) {
+		mfc = mfc_cache_array[it->ct];
+		if (mfc)
+			return mfc;
+	}
+
+	/* exhausted cache_array, show unresolved */
+	read_unlock(&mrt_lock);
+	it->cache = &mfc_unres_queue;
+	it->ct = 0;
+		
+	spin_lock_bh(&mfc_unres_lock);
+	mfc = mfc_unres_queue;
+	if (mfc) 
+		return mfc;
+
+ end_of_list:
+	spin_unlock_bh(&mfc_unres_lock);
+	it->cache = NULL;
+
+	return NULL;
+}
+
+static void ipmr_mfc_seq_stop(struct seq_file *seq, void *v)
+{
+	struct ipmr_mfc_iter *it = seq->private;
+
+	if (it->cache == &mfc_unres_queue)
+		spin_unlock_bh(&mfc_unres_lock);
+	else if (it->cache == mfc_cache_array)
+		read_unlock(&mrt_lock);
+}
+
+static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
+{
+	int n;
+
+	if (v == SEQ_START_TOKEN) {
+		seq_puts(seq, 
+		 "Group    Origin   Iif     Pkts    Bytes    Wrong Oifs\n");
+	} else {
+		const struct mfc_cache *mfc = v;
+		const struct ipmr_mfc_iter *it = seq->private;
+		
+		seq_printf(seq, "%08lX %08lX %-3d %8ld %8ld %8ld",
+			   (unsigned long) mfc->mfc_mcastgrp,
+			   (unsigned long) mfc->mfc_origin,
+			   mfc->mfc_parent,
+			   mfc->mfc_un.res.pkt,
+			   mfc->mfc_un.res.bytes,
+			   mfc->mfc_un.res.wrong_if);
+
+		if (it->cache != &mfc_unres_queue) {
+			for(n = mfc->mfc_un.res.minvif; 
+			    n < mfc->mfc_un.res.maxvif; n++ ) {
+				if(VIF_EXISTS(n) 
+				   && mfc->mfc_un.res.ttls[n] < 255)
+				seq_printf(seq, 
+					   " %2d:%-3d", 
+					   n, mfc->mfc_un.res.ttls[n]);
+			}
+		}
+		seq_putc(seq, '\n');
+	}
+	return 0;
+}
+
+static struct seq_operations ipmr_mfc_seq_ops = {
+	.start = ipmr_mfc_seq_start,
+	.next  = ipmr_mfc_seq_next,
+	.stop  = ipmr_mfc_seq_stop,
+	.show  = ipmr_mfc_seq_show,
+};
+
+static int ipmr_mfc_open(struct inode *inode, struct file *file)
+{
+	struct seq_file *seq;
+	int rc = -ENOMEM;
+	struct ipmr_mfc_iter *s = kmalloc(sizeof(*s), GFP_KERNEL);
+       
+	if (!s)
+		goto out;
+
+	rc = seq_open(file, &ipmr_mfc_seq_ops);
+	if (rc)
+		goto out_kfree;
+
+	seq = file->private_data;
+	seq->private = s;
+out:
+	return rc;
+out_kfree:
+	kfree(s);
+	goto out;
+
+}
+
+static struct file_operations ipmr_mfc_fops = {
+	.owner	 = THIS_MODULE,
+	.open    = ipmr_mfc_open,
+	.read    = seq_read,
+	.llseek  = seq_lseek,
+	.release = seq_release_private,
+};
+#endif	
+
+#ifdef CONFIG_IP_PIMSM_V2
+static struct net_protocol pim_protocol = {
+	.handler	=	pim_rcv,
+};
+#endif
+
+
+/*
+ *	Setup for IP multicast routing
+ */
+ 
+void __init ip_mr_init(void)
+{
+	mrt_cachep = kmem_cache_create("ip_mrt_cache",
+				       sizeof(struct mfc_cache),
+				       0, SLAB_HWCACHE_ALIGN,
+				       NULL, NULL);
+	if (!mrt_cachep)
+		panic("cannot allocate ip_mrt_cache");
+
+	init_timer(&ipmr_expire_timer);
+	ipmr_expire_timer.function=ipmr_expire_process;
+	register_netdevice_notifier(&ip_mr_notifier);
+#ifdef CONFIG_PROC_FS	
+	proc_net_fops_create("ip_mr_vif", 0, &ipmr_vif_fops);
+	proc_net_fops_create("ip_mr_cache", 0, &ipmr_mfc_fops);
+#endif	
+}