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-rw-r--r--net/core/dev_mcast.c299
1 files changed, 299 insertions, 0 deletions
diff --git a/net/core/dev_mcast.c b/net/core/dev_mcast.c
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--- /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);
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