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![Harvey Harrison](/assets/img/avatar_default.png)
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
1180 lines
26 KiB
C
1180 lines
26 KiB
C
/*
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* TUN - Universal TUN/TAP device driver.
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* Copyright (C) 1999-2002 Maxim Krasnyansky <maxk@qualcomm.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* $Id: tun.c,v 1.15 2002/03/01 02:44:24 maxk Exp $
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*/
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/*
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* Changes:
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*
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* Mike Kershaw <dragorn@kismetwireless.net> 2005/08/14
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* Add TUNSETLINK ioctl to set the link encapsulation
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*
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* Mark Smith <markzzzsmith@yahoo.com.au>
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* Use random_ether_addr() for tap MAC address.
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*
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* Harald Roelle <harald.roelle@ifi.lmu.de> 2004/04/20
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* Fixes in packet dropping, queue length setting and queue wakeup.
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* Increased default tx queue length.
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* Added ethtool API.
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* Minor cleanups
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*
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* Daniel Podlejski <underley@underley.eu.org>
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* Modifications for 2.3.99-pre5 kernel.
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*/
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#define DRV_NAME "tun"
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#define DRV_VERSION "1.6"
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#define DRV_DESCRIPTION "Universal TUN/TAP device driver"
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#define DRV_COPYRIGHT "(C) 1999-2004 Max Krasnyansky <maxk@qualcomm.com>"
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#include <linux/module.h>
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#include <linux/errno.h>
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#include <linux/kernel.h>
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#include <linux/major.h>
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#include <linux/slab.h>
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#include <linux/smp_lock.h>
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#include <linux/poll.h>
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#include <linux/fcntl.h>
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#include <linux/init.h>
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#include <linux/skbuff.h>
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#include <linux/netdevice.h>
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#include <linux/etherdevice.h>
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#include <linux/miscdevice.h>
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#include <linux/ethtool.h>
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#include <linux/rtnetlink.h>
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#include <linux/if.h>
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#include <linux/if_arp.h>
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#include <linux/if_ether.h>
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#include <linux/if_tun.h>
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#include <linux/crc32.h>
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#include <linux/nsproxy.h>
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#include <linux/virtio_net.h>
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#include <net/net_namespace.h>
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#include <net/netns/generic.h>
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#include <asm/system.h>
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#include <asm/uaccess.h>
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/* Uncomment to enable debugging */
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/* #define TUN_DEBUG 1 */
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#ifdef TUN_DEBUG
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static int debug;
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#define DBG if(tun->debug)printk
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#define DBG1 if(debug==2)printk
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#else
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#define DBG( a... )
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#define DBG1( a... )
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#endif
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#define FLT_EXACT_COUNT 8
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struct tap_filter {
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unsigned int count; /* Number of addrs. Zero means disabled */
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u32 mask[2]; /* Mask of the hashed addrs */
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unsigned char addr[FLT_EXACT_COUNT][ETH_ALEN];
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};
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struct tun_struct {
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struct list_head list;
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unsigned int flags;
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int attached;
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uid_t owner;
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gid_t group;
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wait_queue_head_t read_wait;
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struct sk_buff_head readq;
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struct net_device *dev;
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struct fasync_struct *fasync;
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struct tap_filter txflt;
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#ifdef TUN_DEBUG
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int debug;
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#endif
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};
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/* TAP filterting */
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static void addr_hash_set(u32 *mask, const u8 *addr)
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{
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int n = ether_crc(ETH_ALEN, addr) >> 26;
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mask[n >> 5] |= (1 << (n & 31));
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}
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static unsigned int addr_hash_test(const u32 *mask, const u8 *addr)
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{
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int n = ether_crc(ETH_ALEN, addr) >> 26;
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return mask[n >> 5] & (1 << (n & 31));
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}
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static int update_filter(struct tap_filter *filter, void __user *arg)
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{
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struct { u8 u[ETH_ALEN]; } *addr;
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struct tun_filter uf;
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int err, alen, n, nexact;
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if (copy_from_user(&uf, arg, sizeof(uf)))
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return -EFAULT;
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if (!uf.count) {
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/* Disabled */
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filter->count = 0;
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return 0;
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}
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alen = ETH_ALEN * uf.count;
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addr = kmalloc(alen, GFP_KERNEL);
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if (!addr)
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return -ENOMEM;
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if (copy_from_user(addr, arg + sizeof(uf), alen)) {
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err = -EFAULT;
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goto done;
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}
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/* The filter is updated without holding any locks. Which is
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* perfectly safe. We disable it first and in the worst
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* case we'll accept a few undesired packets. */
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filter->count = 0;
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wmb();
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/* Use first set of addresses as an exact filter */
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for (n = 0; n < uf.count && n < FLT_EXACT_COUNT; n++)
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memcpy(filter->addr[n], addr[n].u, ETH_ALEN);
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nexact = n;
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/* The rest is hashed */
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memset(filter->mask, 0, sizeof(filter->mask));
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for (; n < uf.count; n++)
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addr_hash_set(filter->mask, addr[n].u);
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/* For ALLMULTI just set the mask to all ones.
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* This overrides the mask populated above. */
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if ((uf.flags & TUN_FLT_ALLMULTI))
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memset(filter->mask, ~0, sizeof(filter->mask));
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/* Now enable the filter */
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wmb();
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filter->count = nexact;
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/* Return the number of exact filters */
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err = nexact;
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done:
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kfree(addr);
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return err;
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}
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/* Returns: 0 - drop, !=0 - accept */
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static int run_filter(struct tap_filter *filter, const struct sk_buff *skb)
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{
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/* Cannot use eth_hdr(skb) here because skb_mac_hdr() is incorrect
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* at this point. */
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struct ethhdr *eh = (struct ethhdr *) skb->data;
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int i;
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/* Exact match */
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for (i = 0; i < filter->count; i++)
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if (!compare_ether_addr(eh->h_dest, filter->addr[i]))
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return 1;
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/* Inexact match (multicast only) */
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if (is_multicast_ether_addr(eh->h_dest))
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return addr_hash_test(filter->mask, eh->h_dest);
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return 0;
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}
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/*
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* Checks whether the packet is accepted or not.
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* Returns: 0 - drop, !=0 - accept
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*/
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static int check_filter(struct tap_filter *filter, const struct sk_buff *skb)
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{
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if (!filter->count)
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return 1;
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return run_filter(filter, skb);
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}
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/* Network device part of the driver */
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static unsigned int tun_net_id;
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struct tun_net {
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struct list_head dev_list;
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};
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static const struct ethtool_ops tun_ethtool_ops;
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/* Net device open. */
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static int tun_net_open(struct net_device *dev)
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{
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netif_start_queue(dev);
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return 0;
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}
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/* Net device close. */
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static int tun_net_close(struct net_device *dev)
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{
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netif_stop_queue(dev);
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return 0;
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}
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/* Net device start xmit */
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static int tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
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{
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struct tun_struct *tun = netdev_priv(dev);
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DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->dev->name, skb->len);
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/* Drop packet if interface is not attached */
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if (!tun->attached)
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goto drop;
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/* Drop if the filter does not like it.
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* This is a noop if the filter is disabled.
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* Filter can be enabled only for the TAP devices. */
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if (!check_filter(&tun->txflt, skb))
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goto drop;
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if (skb_queue_len(&tun->readq) >= dev->tx_queue_len) {
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if (!(tun->flags & TUN_ONE_QUEUE)) {
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/* Normal queueing mode. */
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/* Packet scheduler handles dropping of further packets. */
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netif_stop_queue(dev);
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/* We won't see all dropped packets individually, so overrun
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* error is more appropriate. */
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dev->stats.tx_fifo_errors++;
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} else {
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/* Single queue mode.
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* Driver handles dropping of all packets itself. */
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goto drop;
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}
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}
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/* Enqueue packet */
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skb_queue_tail(&tun->readq, skb);
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dev->trans_start = jiffies;
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/* Notify and wake up reader process */
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if (tun->flags & TUN_FASYNC)
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kill_fasync(&tun->fasync, SIGIO, POLL_IN);
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wake_up_interruptible(&tun->read_wait);
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return 0;
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drop:
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dev->stats.tx_dropped++;
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kfree_skb(skb);
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return 0;
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}
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static void tun_net_mclist(struct net_device *dev)
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{
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/*
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* This callback is supposed to deal with mc filter in
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* _rx_ path and has nothing to do with the _tx_ path.
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* In rx path we always accept everything userspace gives us.
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*/
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return;
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}
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#define MIN_MTU 68
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#define MAX_MTU 65535
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static int
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tun_net_change_mtu(struct net_device *dev, int new_mtu)
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{
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if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU)
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return -EINVAL;
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dev->mtu = new_mtu;
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return 0;
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}
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/* Initialize net device. */
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static void tun_net_init(struct net_device *dev)
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{
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struct tun_struct *tun = netdev_priv(dev);
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switch (tun->flags & TUN_TYPE_MASK) {
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case TUN_TUN_DEV:
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/* Point-to-Point TUN Device */
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dev->hard_header_len = 0;
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dev->addr_len = 0;
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dev->mtu = 1500;
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dev->change_mtu = tun_net_change_mtu;
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/* Zero header length */
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dev->type = ARPHRD_NONE;
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dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
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dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
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break;
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case TUN_TAP_DEV:
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/* Ethernet TAP Device */
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ether_setup(dev);
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dev->change_mtu = tun_net_change_mtu;
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dev->set_multicast_list = tun_net_mclist;
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random_ether_addr(dev->dev_addr);
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dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
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break;
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}
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}
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/* Character device part */
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/* Poll */
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static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
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{
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struct tun_struct *tun = file->private_data;
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unsigned int mask = POLLOUT | POLLWRNORM;
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if (!tun)
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return -EBADFD;
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DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name);
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poll_wait(file, &tun->read_wait, wait);
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if (!skb_queue_empty(&tun->readq))
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mask |= POLLIN | POLLRDNORM;
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return mask;
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}
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/* Get packet from user space buffer */
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static __inline__ ssize_t tun_get_user(struct tun_struct *tun, struct iovec *iv, size_t count)
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{
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struct tun_pi pi = { 0, __constant_htons(ETH_P_IP) };
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struct sk_buff *skb;
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size_t len = count, align = 0;
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struct virtio_net_hdr gso = { 0 };
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if (!(tun->flags & TUN_NO_PI)) {
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if ((len -= sizeof(pi)) > count)
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return -EINVAL;
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if(memcpy_fromiovec((void *)&pi, iv, sizeof(pi)))
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return -EFAULT;
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}
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if (tun->flags & TUN_VNET_HDR) {
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if ((len -= sizeof(gso)) > count)
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return -EINVAL;
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if (memcpy_fromiovec((void *)&gso, iv, sizeof(gso)))
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return -EFAULT;
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if (gso.hdr_len > len)
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return -EINVAL;
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}
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if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) {
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align = NET_IP_ALIGN;
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if (unlikely(len < ETH_HLEN))
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return -EINVAL;
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}
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if (!(skb = alloc_skb(len + align, GFP_KERNEL))) {
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tun->dev->stats.rx_dropped++;
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return -ENOMEM;
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}
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if (align)
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skb_reserve(skb, align);
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if (memcpy_fromiovec(skb_put(skb, len), iv, len)) {
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tun->dev->stats.rx_dropped++;
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kfree_skb(skb);
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return -EFAULT;
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}
|
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|
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if (gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
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if (!skb_partial_csum_set(skb, gso.csum_start,
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gso.csum_offset)) {
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tun->dev->stats.rx_frame_errors++;
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kfree_skb(skb);
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return -EINVAL;
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}
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} else if (tun->flags & TUN_NOCHECKSUM)
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skb->ip_summed = CHECKSUM_UNNECESSARY;
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|
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switch (tun->flags & TUN_TYPE_MASK) {
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case TUN_TUN_DEV:
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if (tun->flags & TUN_NO_PI) {
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switch (skb->data[0] & 0xf0) {
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case 0x40:
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pi.proto = htons(ETH_P_IP);
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break;
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case 0x60:
|
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pi.proto = htons(ETH_P_IPV6);
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break;
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default:
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tun->dev->stats.rx_dropped++;
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kfree_skb(skb);
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return -EINVAL;
|
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}
|
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}
|
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|
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skb_reset_mac_header(skb);
|
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skb->protocol = pi.proto;
|
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skb->dev = tun->dev;
|
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break;
|
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case TUN_TAP_DEV:
|
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skb->protocol = eth_type_trans(skb, tun->dev);
|
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break;
|
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};
|
|
|
|
if (gso.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
|
|
pr_debug("GSO!\n");
|
|
switch (gso.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
|
|
case VIRTIO_NET_HDR_GSO_TCPV4:
|
|
skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
|
|
break;
|
|
case VIRTIO_NET_HDR_GSO_TCPV6:
|
|
skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
|
|
break;
|
|
default:
|
|
tun->dev->stats.rx_frame_errors++;
|
|
kfree_skb(skb);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (gso.gso_type & VIRTIO_NET_HDR_GSO_ECN)
|
|
skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
|
|
|
|
skb_shinfo(skb)->gso_size = gso.gso_size;
|
|
if (skb_shinfo(skb)->gso_size == 0) {
|
|
tun->dev->stats.rx_frame_errors++;
|
|
kfree_skb(skb);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Header must be checked, and gso_segs computed. */
|
|
skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
|
|
skb_shinfo(skb)->gso_segs = 0;
|
|
}
|
|
|
|
netif_rx_ni(skb);
|
|
tun->dev->last_rx = jiffies;
|
|
|
|
tun->dev->stats.rx_packets++;
|
|
tun->dev->stats.rx_bytes += len;
|
|
|
|
return count;
|
|
}
|
|
|
|
static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv,
|
|
unsigned long count, loff_t pos)
|
|
{
|
|
struct tun_struct *tun = iocb->ki_filp->private_data;
|
|
|
|
if (!tun)
|
|
return -EBADFD;
|
|
|
|
DBG(KERN_INFO "%s: tun_chr_write %ld\n", tun->dev->name, count);
|
|
|
|
return tun_get_user(tun, (struct iovec *) iv, iov_length(iv, count));
|
|
}
|
|
|
|
/* Put packet to the user space buffer */
|
|
static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
|
|
struct sk_buff *skb,
|
|
struct iovec *iv, int len)
|
|
{
|
|
struct tun_pi pi = { 0, skb->protocol };
|
|
ssize_t total = 0;
|
|
|
|
if (!(tun->flags & TUN_NO_PI)) {
|
|
if ((len -= sizeof(pi)) < 0)
|
|
return -EINVAL;
|
|
|
|
if (len < skb->len) {
|
|
/* Packet will be striped */
|
|
pi.flags |= TUN_PKT_STRIP;
|
|
}
|
|
|
|
if (memcpy_toiovec(iv, (void *) &pi, sizeof(pi)))
|
|
return -EFAULT;
|
|
total += sizeof(pi);
|
|
}
|
|
|
|
if (tun->flags & TUN_VNET_HDR) {
|
|
struct virtio_net_hdr gso = { 0 }; /* no info leak */
|
|
if ((len -= sizeof(gso)) < 0)
|
|
return -EINVAL;
|
|
|
|
if (skb_is_gso(skb)) {
|
|
struct skb_shared_info *sinfo = skb_shinfo(skb);
|
|
|
|
/* This is a hint as to how much should be linear. */
|
|
gso.hdr_len = skb_headlen(skb);
|
|
gso.gso_size = sinfo->gso_size;
|
|
if (sinfo->gso_type & SKB_GSO_TCPV4)
|
|
gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
|
|
else if (sinfo->gso_type & SKB_GSO_TCPV6)
|
|
gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
|
|
else
|
|
BUG();
|
|
if (sinfo->gso_type & SKB_GSO_TCP_ECN)
|
|
gso.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
|
|
} else
|
|
gso.gso_type = VIRTIO_NET_HDR_GSO_NONE;
|
|
|
|
if (skb->ip_summed == CHECKSUM_PARTIAL) {
|
|
gso.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
|
|
gso.csum_start = skb->csum_start - skb_headroom(skb);
|
|
gso.csum_offset = skb->csum_offset;
|
|
} /* else everything is zero */
|
|
|
|
if (unlikely(memcpy_toiovec(iv, (void *)&gso, sizeof(gso))))
|
|
return -EFAULT;
|
|
total += sizeof(gso);
|
|
}
|
|
|
|
len = min_t(int, skb->len, len);
|
|
|
|
skb_copy_datagram_iovec(skb, 0, iv, len);
|
|
total += len;
|
|
|
|
tun->dev->stats.tx_packets++;
|
|
tun->dev->stats.tx_bytes += len;
|
|
|
|
return total;
|
|
}
|
|
|
|
static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
|
|
unsigned long count, loff_t pos)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct tun_struct *tun = file->private_data;
|
|
DECLARE_WAITQUEUE(wait, current);
|
|
struct sk_buff *skb;
|
|
ssize_t len, ret = 0;
|
|
|
|
if (!tun)
|
|
return -EBADFD;
|
|
|
|
DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name);
|
|
|
|
len = iov_length(iv, count);
|
|
if (len < 0)
|
|
return -EINVAL;
|
|
|
|
add_wait_queue(&tun->read_wait, &wait);
|
|
while (len) {
|
|
current->state = TASK_INTERRUPTIBLE;
|
|
|
|
/* Read frames from the queue */
|
|
if (!(skb=skb_dequeue(&tun->readq))) {
|
|
if (file->f_flags & O_NONBLOCK) {
|
|
ret = -EAGAIN;
|
|
break;
|
|
}
|
|
if (signal_pending(current)) {
|
|
ret = -ERESTARTSYS;
|
|
break;
|
|
}
|
|
|
|
/* Nothing to read, let's sleep */
|
|
schedule();
|
|
continue;
|
|
}
|
|
netif_wake_queue(tun->dev);
|
|
|
|
ret = tun_put_user(tun, skb, (struct iovec *) iv, len);
|
|
kfree_skb(skb);
|
|
break;
|
|
}
|
|
|
|
current->state = TASK_RUNNING;
|
|
remove_wait_queue(&tun->read_wait, &wait);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void tun_setup(struct net_device *dev)
|
|
{
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
|
|
skb_queue_head_init(&tun->readq);
|
|
init_waitqueue_head(&tun->read_wait);
|
|
|
|
tun->owner = -1;
|
|
tun->group = -1;
|
|
|
|
dev->open = tun_net_open;
|
|
dev->hard_start_xmit = tun_net_xmit;
|
|
dev->stop = tun_net_close;
|
|
dev->ethtool_ops = &tun_ethtool_ops;
|
|
dev->destructor = free_netdev;
|
|
dev->features |= NETIF_F_NETNS_LOCAL;
|
|
}
|
|
|
|
static struct tun_struct *tun_get_by_name(struct tun_net *tn, const char *name)
|
|
{
|
|
struct tun_struct *tun;
|
|
|
|
ASSERT_RTNL();
|
|
list_for_each_entry(tun, &tn->dev_list, list) {
|
|
if (!strncmp(tun->dev->name, name, IFNAMSIZ))
|
|
return tun;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
|
|
{
|
|
struct tun_net *tn;
|
|
struct tun_struct *tun;
|
|
struct net_device *dev;
|
|
int err;
|
|
|
|
tn = net_generic(net, tun_net_id);
|
|
tun = tun_get_by_name(tn, ifr->ifr_name);
|
|
if (tun) {
|
|
if (tun->attached)
|
|
return -EBUSY;
|
|
|
|
/* Check permissions */
|
|
if (((tun->owner != -1 &&
|
|
current->euid != tun->owner) ||
|
|
(tun->group != -1 &&
|
|
current->egid != tun->group)) &&
|
|
!capable(CAP_NET_ADMIN))
|
|
return -EPERM;
|
|
}
|
|
else if (__dev_get_by_name(net, ifr->ifr_name))
|
|
return -EINVAL;
|
|
else {
|
|
char *name;
|
|
unsigned long flags = 0;
|
|
|
|
err = -EINVAL;
|
|
|
|
if (!capable(CAP_NET_ADMIN))
|
|
return -EPERM;
|
|
|
|
/* Set dev type */
|
|
if (ifr->ifr_flags & IFF_TUN) {
|
|
/* TUN device */
|
|
flags |= TUN_TUN_DEV;
|
|
name = "tun%d";
|
|
} else if (ifr->ifr_flags & IFF_TAP) {
|
|
/* TAP device */
|
|
flags |= TUN_TAP_DEV;
|
|
name = "tap%d";
|
|
} else
|
|
goto failed;
|
|
|
|
if (*ifr->ifr_name)
|
|
name = ifr->ifr_name;
|
|
|
|
dev = alloc_netdev(sizeof(struct tun_struct), name,
|
|
tun_setup);
|
|
if (!dev)
|
|
return -ENOMEM;
|
|
|
|
dev_net_set(dev, net);
|
|
tun = netdev_priv(dev);
|
|
tun->dev = dev;
|
|
tun->flags = flags;
|
|
tun->txflt.count = 0;
|
|
|
|
tun_net_init(dev);
|
|
|
|
if (strchr(dev->name, '%')) {
|
|
err = dev_alloc_name(dev, dev->name);
|
|
if (err < 0)
|
|
goto err_free_dev;
|
|
}
|
|
|
|
err = register_netdevice(tun->dev);
|
|
if (err < 0)
|
|
goto err_free_dev;
|
|
|
|
list_add(&tun->list, &tn->dev_list);
|
|
}
|
|
|
|
DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name);
|
|
|
|
if (ifr->ifr_flags & IFF_NO_PI)
|
|
tun->flags |= TUN_NO_PI;
|
|
else
|
|
tun->flags &= ~TUN_NO_PI;
|
|
|
|
if (ifr->ifr_flags & IFF_ONE_QUEUE)
|
|
tun->flags |= TUN_ONE_QUEUE;
|
|
else
|
|
tun->flags &= ~TUN_ONE_QUEUE;
|
|
|
|
if (ifr->ifr_flags & IFF_VNET_HDR)
|
|
tun->flags |= TUN_VNET_HDR;
|
|
else
|
|
tun->flags &= ~TUN_VNET_HDR;
|
|
|
|
file->private_data = tun;
|
|
tun->attached = 1;
|
|
get_net(dev_net(tun->dev));
|
|
|
|
/* Make sure persistent devices do not get stuck in
|
|
* xoff state.
|
|
*/
|
|
if (netif_running(tun->dev))
|
|
netif_wake_queue(tun->dev);
|
|
|
|
strcpy(ifr->ifr_name, tun->dev->name);
|
|
return 0;
|
|
|
|
err_free_dev:
|
|
free_netdev(dev);
|
|
failed:
|
|
return err;
|
|
}
|
|
|
|
/* This is like a cut-down ethtool ops, except done via tun fd so no
|
|
* privs required. */
|
|
static int set_offload(struct net_device *dev, unsigned long arg)
|
|
{
|
|
unsigned int old_features, features;
|
|
|
|
old_features = dev->features;
|
|
/* Unset features, set them as we chew on the arg. */
|
|
features = (old_features & ~(NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST
|
|
|NETIF_F_TSO_ECN|NETIF_F_TSO|NETIF_F_TSO6));
|
|
|
|
if (arg & TUN_F_CSUM) {
|
|
features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
|
|
arg &= ~TUN_F_CSUM;
|
|
|
|
if (arg & (TUN_F_TSO4|TUN_F_TSO6)) {
|
|
if (arg & TUN_F_TSO_ECN) {
|
|
features |= NETIF_F_TSO_ECN;
|
|
arg &= ~TUN_F_TSO_ECN;
|
|
}
|
|
if (arg & TUN_F_TSO4)
|
|
features |= NETIF_F_TSO;
|
|
if (arg & TUN_F_TSO6)
|
|
features |= NETIF_F_TSO6;
|
|
arg &= ~(TUN_F_TSO4|TUN_F_TSO6);
|
|
}
|
|
}
|
|
|
|
/* This gives the user a way to test for new features in future by
|
|
* trying to set them. */
|
|
if (arg)
|
|
return -EINVAL;
|
|
|
|
dev->features = features;
|
|
if (old_features != dev->features)
|
|
netdev_features_change(dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int tun_chr_ioctl(struct inode *inode, struct file *file,
|
|
unsigned int cmd, unsigned long arg)
|
|
{
|
|
struct tun_struct *tun = file->private_data;
|
|
void __user* argp = (void __user*)arg;
|
|
struct ifreq ifr;
|
|
int ret;
|
|
DECLARE_MAC_BUF(mac);
|
|
|
|
if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89)
|
|
if (copy_from_user(&ifr, argp, sizeof ifr))
|
|
return -EFAULT;
|
|
|
|
if (cmd == TUNSETIFF && !tun) {
|
|
int err;
|
|
|
|
ifr.ifr_name[IFNAMSIZ-1] = '\0';
|
|
|
|
rtnl_lock();
|
|
err = tun_set_iff(current->nsproxy->net_ns, file, &ifr);
|
|
rtnl_unlock();
|
|
|
|
if (err)
|
|
return err;
|
|
|
|
if (copy_to_user(argp, &ifr, sizeof(ifr)))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
|
|
if (cmd == TUNGETFEATURES) {
|
|
/* Currently this just means: "what IFF flags are valid?".
|
|
* This is needed because we never checked for invalid flags on
|
|
* TUNSETIFF. */
|
|
return put_user(IFF_TUN | IFF_TAP | IFF_NO_PI | IFF_ONE_QUEUE |
|
|
IFF_VNET_HDR,
|
|
(unsigned int __user*)argp);
|
|
}
|
|
|
|
if (!tun)
|
|
return -EBADFD;
|
|
|
|
DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd);
|
|
|
|
switch (cmd) {
|
|
case TUNSETNOCSUM:
|
|
/* Disable/Enable checksum */
|
|
if (arg)
|
|
tun->flags |= TUN_NOCHECKSUM;
|
|
else
|
|
tun->flags &= ~TUN_NOCHECKSUM;
|
|
|
|
DBG(KERN_INFO "%s: checksum %s\n",
|
|
tun->dev->name, arg ? "disabled" : "enabled");
|
|
break;
|
|
|
|
case TUNSETPERSIST:
|
|
/* Disable/Enable persist mode */
|
|
if (arg)
|
|
tun->flags |= TUN_PERSIST;
|
|
else
|
|
tun->flags &= ~TUN_PERSIST;
|
|
|
|
DBG(KERN_INFO "%s: persist %s\n",
|
|
tun->dev->name, arg ? "enabled" : "disabled");
|
|
break;
|
|
|
|
case TUNSETOWNER:
|
|
/* Set owner of the device */
|
|
tun->owner = (uid_t) arg;
|
|
|
|
DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner);
|
|
break;
|
|
|
|
case TUNSETGROUP:
|
|
/* Set group of the device */
|
|
tun->group= (gid_t) arg;
|
|
|
|
DBG(KERN_INFO "%s: group set to %d\n", tun->dev->name, tun->group);
|
|
break;
|
|
|
|
case TUNSETLINK:
|
|
/* Only allow setting the type when the interface is down */
|
|
rtnl_lock();
|
|
if (tun->dev->flags & IFF_UP) {
|
|
DBG(KERN_INFO "%s: Linktype set failed because interface is up\n",
|
|
tun->dev->name);
|
|
ret = -EBUSY;
|
|
} else {
|
|
tun->dev->type = (int) arg;
|
|
DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type);
|
|
ret = 0;
|
|
}
|
|
rtnl_unlock();
|
|
return ret;
|
|
|
|
#ifdef TUN_DEBUG
|
|
case TUNSETDEBUG:
|
|
tun->debug = arg;
|
|
break;
|
|
#endif
|
|
case TUNSETOFFLOAD:
|
|
rtnl_lock();
|
|
ret = set_offload(tun->dev, arg);
|
|
rtnl_unlock();
|
|
return ret;
|
|
|
|
case TUNSETTXFILTER:
|
|
/* Can be set only for TAPs */
|
|
if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
|
|
return -EINVAL;
|
|
rtnl_lock();
|
|
ret = update_filter(&tun->txflt, (void __user *)arg);
|
|
rtnl_unlock();
|
|
return ret;
|
|
|
|
case SIOCGIFHWADDR:
|
|
/* Get hw addres */
|
|
memcpy(ifr.ifr_hwaddr.sa_data, tun->dev->dev_addr, ETH_ALEN);
|
|
ifr.ifr_hwaddr.sa_family = tun->dev->type;
|
|
if (copy_to_user(argp, &ifr, sizeof ifr))
|
|
return -EFAULT;
|
|
return 0;
|
|
|
|
case SIOCSIFHWADDR:
|
|
/* Set hw address */
|
|
DBG(KERN_DEBUG "%s: set hw address: %s\n",
|
|
tun->dev->name, print_mac(mac, ifr.ifr_hwaddr.sa_data));
|
|
|
|
rtnl_lock();
|
|
ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
|
|
rtnl_unlock();
|
|
return ret;
|
|
|
|
default:
|
|
return -EINVAL;
|
|
};
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int tun_chr_fasync(int fd, struct file *file, int on)
|
|
{
|
|
struct tun_struct *tun = file->private_data;
|
|
int ret;
|
|
|
|
if (!tun)
|
|
return -EBADFD;
|
|
|
|
DBG(KERN_INFO "%s: tun_chr_fasync %d\n", tun->dev->name, on);
|
|
|
|
lock_kernel();
|
|
if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0)
|
|
goto out;
|
|
|
|
if (on) {
|
|
ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0);
|
|
if (ret)
|
|
goto out;
|
|
tun->flags |= TUN_FASYNC;
|
|
} else
|
|
tun->flags &= ~TUN_FASYNC;
|
|
ret = 0;
|
|
out:
|
|
unlock_kernel();
|
|
return ret;
|
|
}
|
|
|
|
static int tun_chr_open(struct inode *inode, struct file * file)
|
|
{
|
|
cycle_kernel_lock();
|
|
DBG1(KERN_INFO "tunX: tun_chr_open\n");
|
|
file->private_data = NULL;
|
|
return 0;
|
|
}
|
|
|
|
static int tun_chr_close(struct inode *inode, struct file *file)
|
|
{
|
|
struct tun_struct *tun = file->private_data;
|
|
|
|
if (!tun)
|
|
return 0;
|
|
|
|
DBG(KERN_INFO "%s: tun_chr_close\n", tun->dev->name);
|
|
|
|
tun_chr_fasync(-1, file, 0);
|
|
|
|
rtnl_lock();
|
|
|
|
/* Detach from net device */
|
|
file->private_data = NULL;
|
|
tun->attached = 0;
|
|
put_net(dev_net(tun->dev));
|
|
|
|
/* Drop read queue */
|
|
skb_queue_purge(&tun->readq);
|
|
|
|
if (!(tun->flags & TUN_PERSIST)) {
|
|
list_del(&tun->list);
|
|
unregister_netdevice(tun->dev);
|
|
}
|
|
|
|
rtnl_unlock();
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct file_operations tun_fops = {
|
|
.owner = THIS_MODULE,
|
|
.llseek = no_llseek,
|
|
.read = do_sync_read,
|
|
.aio_read = tun_chr_aio_read,
|
|
.write = do_sync_write,
|
|
.aio_write = tun_chr_aio_write,
|
|
.poll = tun_chr_poll,
|
|
.ioctl = tun_chr_ioctl,
|
|
.open = tun_chr_open,
|
|
.release = tun_chr_close,
|
|
.fasync = tun_chr_fasync
|
|
};
|
|
|
|
static struct miscdevice tun_miscdev = {
|
|
.minor = TUN_MINOR,
|
|
.name = "tun",
|
|
.fops = &tun_fops,
|
|
};
|
|
|
|
/* ethtool interface */
|
|
|
|
static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
|
|
{
|
|
cmd->supported = 0;
|
|
cmd->advertising = 0;
|
|
cmd->speed = SPEED_10;
|
|
cmd->duplex = DUPLEX_FULL;
|
|
cmd->port = PORT_TP;
|
|
cmd->phy_address = 0;
|
|
cmd->transceiver = XCVR_INTERNAL;
|
|
cmd->autoneg = AUTONEG_DISABLE;
|
|
cmd->maxtxpkt = 0;
|
|
cmd->maxrxpkt = 0;
|
|
return 0;
|
|
}
|
|
|
|
static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
|
|
{
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
|
|
strcpy(info->driver, DRV_NAME);
|
|
strcpy(info->version, DRV_VERSION);
|
|
strcpy(info->fw_version, "N/A");
|
|
|
|
switch (tun->flags & TUN_TYPE_MASK) {
|
|
case TUN_TUN_DEV:
|
|
strcpy(info->bus_info, "tun");
|
|
break;
|
|
case TUN_TAP_DEV:
|
|
strcpy(info->bus_info, "tap");
|
|
break;
|
|
}
|
|
}
|
|
|
|
static u32 tun_get_msglevel(struct net_device *dev)
|
|
{
|
|
#ifdef TUN_DEBUG
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
return tun->debug;
|
|
#else
|
|
return -EOPNOTSUPP;
|
|
#endif
|
|
}
|
|
|
|
static void tun_set_msglevel(struct net_device *dev, u32 value)
|
|
{
|
|
#ifdef TUN_DEBUG
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
tun->debug = value;
|
|
#endif
|
|
}
|
|
|
|
static u32 tun_get_link(struct net_device *dev)
|
|
{
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
return tun->attached;
|
|
}
|
|
|
|
static u32 tun_get_rx_csum(struct net_device *dev)
|
|
{
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
return (tun->flags & TUN_NOCHECKSUM) == 0;
|
|
}
|
|
|
|
static int tun_set_rx_csum(struct net_device *dev, u32 data)
|
|
{
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
if (data)
|
|
tun->flags &= ~TUN_NOCHECKSUM;
|
|
else
|
|
tun->flags |= TUN_NOCHECKSUM;
|
|
return 0;
|
|
}
|
|
|
|
static const struct ethtool_ops tun_ethtool_ops = {
|
|
.get_settings = tun_get_settings,
|
|
.get_drvinfo = tun_get_drvinfo,
|
|
.get_msglevel = tun_get_msglevel,
|
|
.set_msglevel = tun_set_msglevel,
|
|
.get_link = tun_get_link,
|
|
.get_rx_csum = tun_get_rx_csum,
|
|
.set_rx_csum = tun_set_rx_csum
|
|
};
|
|
|
|
static int tun_init_net(struct net *net)
|
|
{
|
|
struct tun_net *tn;
|
|
|
|
tn = kmalloc(sizeof(*tn), GFP_KERNEL);
|
|
if (tn == NULL)
|
|
return -ENOMEM;
|
|
|
|
INIT_LIST_HEAD(&tn->dev_list);
|
|
|
|
if (net_assign_generic(net, tun_net_id, tn)) {
|
|
kfree(tn);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void tun_exit_net(struct net *net)
|
|
{
|
|
struct tun_net *tn;
|
|
struct tun_struct *tun, *nxt;
|
|
|
|
tn = net_generic(net, tun_net_id);
|
|
|
|
rtnl_lock();
|
|
list_for_each_entry_safe(tun, nxt, &tn->dev_list, list) {
|
|
DBG(KERN_INFO "%s cleaned up\n", tun->dev->name);
|
|
unregister_netdevice(tun->dev);
|
|
}
|
|
rtnl_unlock();
|
|
|
|
kfree(tn);
|
|
}
|
|
|
|
static struct pernet_operations tun_net_ops = {
|
|
.init = tun_init_net,
|
|
.exit = tun_exit_net,
|
|
};
|
|
|
|
static int __init tun_init(void)
|
|
{
|
|
int ret = 0;
|
|
|
|
printk(KERN_INFO "tun: %s, %s\n", DRV_DESCRIPTION, DRV_VERSION);
|
|
printk(KERN_INFO "tun: %s\n", DRV_COPYRIGHT);
|
|
|
|
ret = register_pernet_gen_device(&tun_net_id, &tun_net_ops);
|
|
if (ret) {
|
|
printk(KERN_ERR "tun: Can't register pernet ops\n");
|
|
goto err_pernet;
|
|
}
|
|
|
|
ret = misc_register(&tun_miscdev);
|
|
if (ret) {
|
|
printk(KERN_ERR "tun: Can't register misc device %d\n", TUN_MINOR);
|
|
goto err_misc;
|
|
}
|
|
return 0;
|
|
|
|
err_misc:
|
|
unregister_pernet_gen_device(tun_net_id, &tun_net_ops);
|
|
err_pernet:
|
|
return ret;
|
|
}
|
|
|
|
static void tun_cleanup(void)
|
|
{
|
|
misc_deregister(&tun_miscdev);
|
|
unregister_pernet_gen_device(tun_net_id, &tun_net_ops);
|
|
}
|
|
|
|
module_init(tun_init);
|
|
module_exit(tun_cleanup);
|
|
MODULE_DESCRIPTION(DRV_DESCRIPTION);
|
|
MODULE_AUTHOR(DRV_COPYRIGHT);
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS_MISCDEV(TUN_MINOR);
|