Initial revision

1 files changed, 390 insertions, 0 deletions

diff --git a/pfinet/linux-inet/igmp.c b/pfinet/linux-inet/igmp.c
new file mode 100644
index 00000000..eebf3b77
--- /dev/null
+++ b/pfinet/linux-inet/igmp.c
@@ -0,0 +1,390 @@
+/*
+ *	Linux NET3:	Internet Gateway Management Protocol  [IGMP]
+ *
+ *	Authors:
+ *		Alan Cox <Alan.Cox@linux.org>	
+ *
+ *	WARNING:
+ *		This is a 'preliminary' implementation... on your own head
+ *	be it.
+ *
+ *	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.
+ */
+ 
+ 
+#include <asm/segment.h>
+#include <asm/system.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/string.h>
+#include <linux/config.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/in.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include "ip.h"
+#include "protocol.h"
+#include "route.h"
+#include <linux/skbuff.h>
+#include "sock.h"
+#include <linux/igmp.h>
+
+#ifdef CONFIG_IP_MULTICAST
+
+
+/*
+ *	Timer management
+ */
+ 
+ 
+static void igmp_stop_timer(struct ip_mc_list *im)
+{
+	del_timer(&im->timer);
+	im->tm_running=0;
+}
+
+static int random(void)
+{
+	static unsigned long seed=152L;
+	seed=seed*69069L+1;
+	return seed^jiffies;
+}
+
+
+static void igmp_start_timer(struct ip_mc_list *im)
+{
+	int tv;
+	if(im->tm_running)
+		return;
+	tv=random()%(10*HZ);		/* Pick a number any number 8) */
+	im->timer.expires=tv;
+	im->tm_running=1;
+	add_timer(&im->timer);
+}
+ 
+/*
+ *	Send an IGMP report.
+ */
+
+#define MAX_IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+64)
+
+static void igmp_send_report(struct device *dev, unsigned long address, int type)
+{
+	struct sk_buff *skb=alloc_skb(MAX_IGMP_SIZE, GFP_ATOMIC);
+	int tmp;
+	struct igmphdr *igh;
+	
+	if(skb==NULL)
+		return;
+	tmp=ip_build_header(skb, INADDR_ANY, address, &dev, IPPROTO_IGMP, NULL,
+				skb->mem_len, 0, 1);
+	if(tmp<0)
+	{
+		kfree_skb(skb, FREE_WRITE);
+		return;
+	}
+	igh=(struct igmphdr *)(skb->data+tmp);
+	skb->len=tmp+sizeof(*igh);
+	igh->csum=0;
+	igh->unused=0;
+	igh->type=type;
+	igh->group=address;
+	igh->csum=ip_compute_csum((void *)igh,sizeof(*igh));
+	ip_queue_xmit(NULL,dev,skb,1);
+}
+
+
+static void igmp_timer_expire(unsigned long data)
+{
+	struct ip_mc_list *im=(struct ip_mc_list *)data;
+	igmp_stop_timer(im);
+	igmp_send_report(im->interface, im->multiaddr, IGMP_HOST_MEMBERSHIP_REPORT);
+}
+
+static void igmp_init_timer(struct ip_mc_list *im)
+{
+	im->tm_running=0;
+	init_timer(&im->timer);
+	im->timer.data=(unsigned long)im;
+	im->timer.function=&igmp_timer_expire;
+}
+	
+
+static void igmp_heard_report(struct device *dev, unsigned long address)
+{
+	struct ip_mc_list *im;
+	for(im=dev->ip_mc_list;im!=NULL;im=im->next)
+		if(im->multiaddr==address)
+			igmp_stop_timer(im);
+}
+
+static void igmp_heard_query(struct device *dev)
+{
+	struct ip_mc_list *im;
+	for(im=dev->ip_mc_list;im!=NULL;im=im->next)
+		if(!im->tm_running && im->multiaddr!=IGMP_ALL_HOSTS)
+			igmp_start_timer(im);
+}
+
+/*
+ *	Map a multicast IP onto multicast MAC for type ethernet.
+ */
+ 
+static void ip_mc_map(unsigned long addr, char *buf)
+{
+	addr=ntohl(addr);
+	buf[0]=0x01;
+	buf[1]=0x00;
+	buf[2]=0x5e;
+	buf[5]=addr&0xFF;
+	addr>>=8;
+	buf[4]=addr&0xFF;
+	addr>>=8;
+	buf[3]=addr&0x7F;
+}
+
+/*
+ *	Add a filter to a device
+ */
+ 
+void ip_mc_filter_add(struct device *dev, unsigned long addr)
+{
+	char buf[6];
+	if(dev->type!=ARPHRD_ETHER)
+		return;	/* Only do ethernet now */
+	ip_mc_map(addr,buf);	
+	dev_mc_add(dev,buf,ETH_ALEN,0);
+}
+
+/*
+ *	Remove a filter from a device
+ */
+ 
+void ip_mc_filter_del(struct device *dev, unsigned long addr)
+{
+	char buf[6];
+	if(dev->type!=ARPHRD_ETHER)
+		return;	/* Only do ethernet now */
+	ip_mc_map(addr,buf);	
+	dev_mc_delete(dev,buf,ETH_ALEN,0);
+}
+
+static void igmp_group_dropped(struct ip_mc_list *im)
+{
+	del_timer(&im->timer);
+	igmp_send_report(im->interface, im->multiaddr, IGMP_HOST_LEAVE_MESSAGE);
+	ip_mc_filter_del(im->interface, im->multiaddr);
+/*	printk("Left group %lX\n",im->multiaddr);*/
+}
+
+static void igmp_group_added(struct ip_mc_list *im)
+{
+	igmp_init_timer(im);
+	igmp_send_report(im->interface, im->multiaddr, IGMP_HOST_MEMBERSHIP_REPORT);
+	ip_mc_filter_add(im->interface, im->multiaddr);
+/*	printk("Joined group %lX\n",im->multiaddr);*/
+}
+
+int igmp_rcv(struct sk_buff *skb, struct device *dev, struct options *opt,
+	unsigned long daddr, unsigned short len, unsigned long saddr, int redo,
+	struct inet_protocol *protocol)
+{
+	/* This basically follows the spec line by line -- see RFC1112 */
+	struct igmphdr *igh=(struct igmphdr *)skb->h.raw;
+	
+	if(skb->ip_hdr->ttl!=1 || ip_compute_csum((void *)igh,sizeof(*igh)))
+	{
+		kfree_skb(skb, FREE_READ);
+		return 0;
+	}
+	
+	if(igh->type==IGMP_HOST_MEMBERSHIP_QUERY && daddr==IGMP_ALL_HOSTS)
+		igmp_heard_query(dev);
+	if(igh->type==IGMP_HOST_MEMBERSHIP_REPORT && daddr==igh->group)
+		igmp_heard_report(dev,igh->group);
+	kfree_skb(skb, FREE_READ);
+	return 0;
+}
+
+/*
+ *	Multicast list managers
+ */
+ 
+ 
+/*
+ *	A socket has joined a multicast group on device dev.
+ */
+  
+static void ip_mc_inc_group(struct device *dev, unsigned long addr)
+{
+	struct ip_mc_list *i;
+	for(i=dev->ip_mc_list;i!=NULL;i=i->next)
+	{
+		if(i->multiaddr==addr)
+		{
+			i->users++;
+			return;
+		}
+	}
+	i=(struct ip_mc_list *)kmalloc(sizeof(*i), GFP_KERNEL);
+	if(!i)
+		return;
+	i->users=1;
+	i->interface=dev;
+	i->multiaddr=addr;
+	i->next=dev->ip_mc_list;
+	igmp_group_added(i);
+	dev->ip_mc_list=i;
+}
+
+/*
+ *	A socket has left a multicast group on device dev
+ */
+	
+static void ip_mc_dec_group(struct device *dev, unsigned long addr)
+{
+	struct ip_mc_list **i;
+	for(i=&(dev->ip_mc_list);(*i)!=NULL;i=&(*i)->next)
+	{
+		if((*i)->multiaddr==addr)
+		{
+			if(--((*i)->users))
+				return;
+			else
+			{
+				struct ip_mc_list *tmp= *i;
+				igmp_group_dropped(tmp);
+				*i=(*i)->next;
+				kfree_s(tmp,sizeof(*tmp));
+			}
+		}
+	}
+}
+
+/*
+ *	Device going down: Clean up.
+ */
+ 
+void ip_mc_drop_device(struct device *dev)
+{
+	struct ip_mc_list *i;
+	struct ip_mc_list *j;
+	for(i=dev->ip_mc_list;i!=NULL;i=j)
+	{
+		j=i->next;
+		kfree_s(i,sizeof(*i));
+	}
+	dev->ip_mc_list=NULL;
+}
+
+/*
+ *	Device going up. Make sure it is in all hosts
+ */
+ 
+void ip_mc_allhost(struct device *dev)
+{
+	struct ip_mc_list *i;
+	for(i=dev->ip_mc_list;i!=NULL;i=i->next)
+		if(i->multiaddr==IGMP_ALL_HOSTS)
+			return;
+	i=(struct ip_mc_list *)kmalloc(sizeof(*i), GFP_KERNEL);
+	if(!i)
+		return;
+	i->users=1;
+	i->interface=dev;
+	i->multiaddr=IGMP_ALL_HOSTS;
+	i->next=dev->ip_mc_list;
+	dev->ip_mc_list=i;
+	ip_mc_filter_add(i->interface, i->multiaddr);
+
+}	
+ 
+/*
+ *	Join a socket to a group
+ */
+ 
+int ip_mc_join_group(struct sock *sk , struct device *dev, unsigned long addr)
+{
+	int unused= -1;
+	int i;
+	if(!MULTICAST(addr))
+		return -EINVAL;
+	if(!(dev->flags&IFF_MULTICAST))
+		return -EADDRNOTAVAIL;
+	if(sk->ip_mc_list==NULL)
+	{
+		if((sk->ip_mc_list=(struct ip_mc_socklist *)kmalloc(sizeof(*sk->ip_mc_list), GFP_KERNEL))==NULL)
+			return -ENOMEM;
+		memset(sk->ip_mc_list,'\0',sizeof(*sk->ip_mc_list));
+	}
+	for(i=0;i<IP_MAX_MEMBERSHIPS;i++)
+	{
+		if(sk->ip_mc_list->multiaddr[i]==addr && sk->ip_mc_list->multidev[i]==dev)
+			return -EADDRINUSE;
+		if(sk->ip_mc_list->multidev[i]==NULL)
+			unused=i;
+	}
+	
+	if(unused==-1)
+		return -ENOBUFS;
+	sk->ip_mc_list->multiaddr[unused]=addr;
+	sk->ip_mc_list->multidev[unused]=dev;
+	ip_mc_inc_group(dev,addr);
+	return 0;
+}
+
+/*
+ *	Ask a socket to leave a group.
+ */
+ 
+int ip_mc_leave_group(struct sock *sk, struct device *dev, unsigned long addr)
+{
+	int i;
+	if(!MULTICAST(addr))
+		return -EINVAL;
+	if(!(dev->flags&IFF_MULTICAST))
+		return -EADDRNOTAVAIL;
+	if(sk->ip_mc_list==NULL)
+		return -EADDRNOTAVAIL;
+		
+	for(i=0;i<IP_MAX_MEMBERSHIPS;i++)
+	{
+		if(sk->ip_mc_list->multiaddr[i]==addr && sk->ip_mc_list->multidev[i]==dev)
+		{
+			sk->ip_mc_list->multidev[i]=NULL;
+			ip_mc_dec_group(dev,addr);
+			return 0;
+		}
+	}
+	return -EADDRNOTAVAIL;
+}
+
+/*
+ *	A socket is closing.
+ */
+ 
+void ip_mc_drop_socket(struct sock *sk)
+{
+	int i;
+	
+	if(sk->ip_mc_list==NULL)
+		return;
+		
+	for(i=0;i<IP_MAX_MEMBERSHIPS;i++)
+	{
+		if(sk->ip_mc_list->multidev[i])
+		{
+			ip_mc_dec_group(sk->ip_mc_list->multidev[i], sk->ip_mc_list->multiaddr[i]);
+			sk->ip_mc_list->multidev[i]=NULL;
+		}
+	}
+	kfree_s(sk->ip_mc_list,sizeof(*sk->ip_mc_list));
+	sk->ip_mc_list=NULL;
+}
+
+#endif