1 files changed, 299 insertions, 0 deletions
diff --git a/net/core/dev_mcast.c b/net/core/dev_mcast.c
new file mode 100644
index 000000000000..db098ff3cd6a
--- /dev/null
+++ b/net/core/dev_mcast.c
@@ -0,0 +1,299 @@
+/*
+ *	Linux NET3:	Multicast List maintenance. 
+ *
+ *	Authors:
+ *		Tim Kordas <tjk@nostromo.eeap.cwru.edu> 
+ *		Richard Underwood <richard@wuzz.demon.co.uk>
+ *
+ *	Stir fried together from the IP multicast and CAP patches above
+ *		Alan Cox <Alan.Cox@linux.org>	
+ *
+ *	Fixes:
+ *		Alan Cox	:	Update the device on a real delete
+ *					rather than any time but...
+ *		Alan Cox	:	IFF_ALLMULTI support.
+ *		Alan Cox	: 	New format set_multicast_list() calls.
+ *		Gleb Natapov    :       Remove dev_mc_lock.
+ *
+ *	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 <linux/config.h> 
+#include <linux/module.h> 
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <linux/bitops.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/if_ether.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/init.h>
+#include <net/ip.h>
+#include <net/route.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <net/arp.h>
+
+
+/*
+ *	Device multicast list maintenance. 
+ *
+ *	This is used both by IP and by the user level maintenance functions. 
+ *	Unlike BSD we maintain a usage count on a given multicast address so 
+ *	that a casual user application can add/delete multicasts used by 
+ *	protocols without doing damage to the protocols when it deletes the
+ *	entries. It also helps IP as it tracks overlapping maps.
+ *
+ *	Device mc lists are changed by bh at least if IPv6 is enabled,
+ *	so that it must be bh protected.
+ *
+ *	We block accesses to device mc filters with dev->xmit_lock.
+ */
+
+/*
+ *	Update the multicast list into the physical NIC controller.
+ */
+ 
+static void __dev_mc_upload(struct net_device *dev)
+{
+	/* Don't do anything till we up the interface
+	 * [dev_open will call this function so the list will
+	 * stay sane]
+	 */
+
+	if (!(dev->flags&IFF_UP))
+		return;
+
+	/*
+	 *	Devices with no set multicast or which have been
+	 *	detached don't get set.
+	 */
+
+	if (dev->set_multicast_list == NULL ||
+	    !netif_device_present(dev))
+		return;
+
+	dev->set_multicast_list(dev);
+}
+
+void dev_mc_upload(struct net_device *dev)
+{
+	spin_lock_bh(&dev->xmit_lock);
+	__dev_mc_upload(dev);
+	spin_unlock_bh(&dev->xmit_lock);
+}
+
+/*
+ *	Delete a device level multicast
+ */
+ 
+int dev_mc_delete(struct net_device *dev, void *addr, int alen, int glbl)
+{
+	int err = 0;
+	struct dev_mc_list *dmi, **dmip;
+
+	spin_lock_bh(&dev->xmit_lock);
+
+	for (dmip = &dev->mc_list; (dmi = *dmip) != NULL; dmip = &dmi->next) {
+		/*
+		 *	Find the entry we want to delete. The device could
+		 *	have variable length entries so check these too.
+		 */
+		if (memcmp(dmi->dmi_addr, addr, dmi->dmi_addrlen) == 0 &&
+		    alen == dmi->dmi_addrlen) {
+			if (glbl) {
+				int old_glbl = dmi->dmi_gusers;
+				dmi->dmi_gusers = 0;
+				if (old_glbl == 0)
+					break;
+			}
+			if (--dmi->dmi_users)
+				goto done;
+
+			/*
+			 *	Last user. So delete the entry.
+			 */
+			*dmip = dmi->next;
+			dev->mc_count--;
+
+			kfree(dmi);
+
+			/*
+			 *	We have altered the list, so the card
+			 *	loaded filter is now wrong. Fix it
+			 */
+			__dev_mc_upload(dev);
+			
+			spin_unlock_bh(&dev->xmit_lock);
+			return 0;
+		}
+	}
+	err = -ENOENT;
+done:
+	spin_unlock_bh(&dev->xmit_lock);
+	return err;
+}
+
+/*
+ *	Add a device level multicast
+ */
+ 
+int dev_mc_add(struct net_device *dev, void *addr, int alen, int glbl)
+{
+	int err = 0;
+	struct dev_mc_list *dmi, *dmi1;
+
+	dmi1 = (struct dev_mc_list *)kmalloc(sizeof(*dmi), GFP_ATOMIC);
+
+	spin_lock_bh(&dev->xmit_lock);
+	for (dmi = dev->mc_list; dmi != NULL; dmi = dmi->next) {
+		if (memcmp(dmi->dmi_addr, addr, dmi->dmi_addrlen) == 0 &&
+		    dmi->dmi_addrlen == alen) {
+			if (glbl) {
+				int old_glbl = dmi->dmi_gusers;
+				dmi->dmi_gusers = 1;
+				if (old_glbl)
+					goto done;
+			}
+			dmi->dmi_users++;
+			goto done;
+		}
+	}
+
+	if ((dmi = dmi1) == NULL) {
+		spin_unlock_bh(&dev->xmit_lock);
+		return -ENOMEM;
+	}
+	memcpy(dmi->dmi_addr, addr, alen);
+	dmi->dmi_addrlen = alen;
+	dmi->next = dev->mc_list;
+	dmi->dmi_users = 1;
+	dmi->dmi_gusers = glbl ? 1 : 0;
+	dev->mc_list = dmi;
+	dev->mc_count++;
+
+	__dev_mc_upload(dev);
+	
+	spin_unlock_bh(&dev->xmit_lock);
+	return 0;
+
+done:
+	spin_unlock_bh(&dev->xmit_lock);
+	if (dmi1)
+		kfree(dmi1);
+	return err;
+}
+
+/*
+ *	Discard multicast list when a device is downed
+ */
+
+void dev_mc_discard(struct net_device *dev)
+{
+	spin_lock_bh(&dev->xmit_lock);
+	
+	while (dev->mc_list != NULL) {
+		struct dev_mc_list *tmp = dev->mc_list;
+		dev->mc_list = tmp->next;
+		if (tmp->dmi_users > tmp->dmi_gusers)
+			printk("dev_mc_discard: multicast leakage! dmi_users=%d\n", tmp->dmi_users);
+		kfree(tmp);
+	}
+	dev->mc_count = 0;
+
+	spin_unlock_bh(&dev->xmit_lock);
+}
+
+#ifdef CONFIG_PROC_FS
+static void *dev_mc_seq_start(struct seq_file *seq, loff_t *pos)
+{
+	struct net_device *dev;
+	loff_t off = 0;
+
+	read_lock(&dev_base_lock);
+	for (dev = dev_base; dev; dev = dev->next) {
+		if (off++ == *pos) 
+			return dev;
+	}
+	return NULL;
+}
+
+static void *dev_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	struct net_device *dev = v;
+	++*pos;
+	return dev->next;
+}
+
+static void dev_mc_seq_stop(struct seq_file *seq, void *v)
+{
+	read_unlock(&dev_base_lock);
+}
+
+
+static int dev_mc_seq_show(struct seq_file *seq, void *v)
+{
+	struct dev_mc_list *m;
+	struct net_device *dev = v;
+
+	spin_lock_bh(&dev->xmit_lock);
+	for (m = dev->mc_list; m; m = m->next) {
+		int i;
+
+		seq_printf(seq, "%-4d %-15s %-5d %-5d ", dev->ifindex,
+			   dev->name, m->dmi_users, m->dmi_gusers);
+
+		for (i = 0; i < m->dmi_addrlen; i++)
+			seq_printf(seq, "%02x", m->dmi_addr[i]);
+
+		seq_putc(seq, '\n');
+	}
+	spin_unlock_bh(&dev->xmit_lock);
+	return 0;
+}
+
+static struct seq_operations dev_mc_seq_ops = {
+	.start = dev_mc_seq_start,
+	.next  = dev_mc_seq_next,
+	.stop  = dev_mc_seq_stop,
+	.show  = dev_mc_seq_show,
+};
+
+static int dev_mc_seq_open(struct inode *inode, struct file *file)
+{
+	return seq_open(file, &dev_mc_seq_ops);
+}
+
+static struct file_operations dev_mc_seq_fops = {
+	.owner	 = THIS_MODULE,
+	.open    = dev_mc_seq_open,
+	.read    = seq_read,
+	.llseek  = seq_lseek,
+	.release = seq_release,
+};
+
+#endif
+
+void __init dev_mcast_init(void)
+{
+	proc_net_fops_create("dev_mcast", 0, &dev_mc_seq_fops);
+}
+
+EXPORT_SYMBOL(dev_mc_add);
+EXPORT_SYMBOL(dev_mc_delete);
+EXPORT_SYMBOL(dev_mc_upload);