| /* |
| * TUN - Universal TUN/TAP device driver. |
| * Copyright (C) 1999-2002 Maxim Krasnyansky <maxk@qualcomm.com> |
| * |
| * 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. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * $Id: tun.c,v 1.15 2002/03/01 02:44:24 maxk Exp $ |
| */ |
| |
| /* |
| * Changes: |
| * |
| * Mike Kershaw <dragorn@kismetwireless.net> 2005/08/14 |
| * Add TUNSETLINK ioctl to set the link encapsulation |
| * |
| * Mark Smith <markzzzsmith@yahoo.com.au> |
| * Use random_ether_addr() for tap MAC address. |
| * |
| * Harald Roelle <harald.roelle@ifi.lmu.de> 2004/04/20 |
| * Fixes in packet dropping, queue length setting and queue wakeup. |
| * Increased default tx queue length. |
| * Added ethtool API. |
| * Minor cleanups |
| * |
| * Daniel Podlejski <underley@underley.eu.org> |
| * Modifications for 2.3.99-pre5 kernel. |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #define DRV_NAME "tun" |
| #define DRV_VERSION "1.6" |
| #define DRV_DESCRIPTION "Universal TUN/TAP device driver" |
| #define DRV_COPYRIGHT "(C) 1999-2004 Max Krasnyansky <maxk@qualcomm.com>" |
| |
| #include <linux/module.h> |
| #include <linux/errno.h> |
| #include <linux/kernel.h> |
| #include <linux/major.h> |
| #include <linux/slab.h> |
| #include <linux/poll.h> |
| #include <linux/fcntl.h> |
| #include <linux/init.h> |
| #include <linux/skbuff.h> |
| #include <linux/netdevice.h> |
| #include <linux/etherdevice.h> |
| #include <linux/miscdevice.h> |
| #include <linux/ethtool.h> |
| #include <linux/rtnetlink.h> |
| #include <linux/compat.h> |
| #include <linux/if.h> |
| #include <linux/if_arp.h> |
| #include <linux/if_ether.h> |
| #include <linux/if_tun.h> |
| #include <linux/crc32.h> |
| #include <linux/nsproxy.h> |
| #include <linux/virtio_net.h> |
| #include <linux/rcupdate.h> |
| #include <net/net_namespace.h> |
| #include <net/netns/generic.h> |
| #include <net/rtnetlink.h> |
| #include <net/sock.h> |
| |
| #include <asm/system.h> |
| #include <asm/uaccess.h> |
| |
| /* Uncomment to enable debugging */ |
| /* #define TUN_DEBUG 1 */ |
| |
| #ifdef TUN_DEBUG |
| static int debug; |
| |
| #define tun_debug(level, tun, fmt, args...) \ |
| do { \ |
| if (tun->debug) \ |
| netdev_printk(level, tun->dev, fmt, ##args); \ |
| } while (0) |
| #define DBG1(level, fmt, args...) \ |
| do { \ |
| if (debug == 2) \ |
| printk(level fmt, ##args); \ |
| } while (0) |
| #else |
| #define tun_debug(level, tun, fmt, args...) \ |
| do { \ |
| if (0) \ |
| netdev_printk(level, tun->dev, fmt, ##args); \ |
| } while (0) |
| #define DBG1(level, fmt, args...) \ |
| do { \ |
| if (0) \ |
| printk(level fmt, ##args); \ |
| } while (0) |
| #endif |
| |
| #define FLT_EXACT_COUNT 8 |
| struct tap_filter { |
| unsigned int count; /* Number of addrs. Zero means disabled */ |
| u32 mask[2]; /* Mask of the hashed addrs */ |
| unsigned char addr[FLT_EXACT_COUNT][ETH_ALEN]; |
| }; |
| |
| struct tun_file { |
| atomic_t count; |
| struct tun_struct *tun; |
| struct net *net; |
| }; |
| |
| struct tun_sock; |
| |
| struct tun_struct { |
| struct tun_file *tfile; |
| unsigned int flags; |
| uid_t owner; |
| gid_t group; |
| |
| struct net_device *dev; |
| u32 set_features; |
| #define TUN_USER_FEATURES (NETIF_F_HW_CSUM|NETIF_F_TSO_ECN|NETIF_F_TSO| \ |
| NETIF_F_TSO6|NETIF_F_UFO) |
| struct fasync_struct *fasync; |
| |
| struct tap_filter txflt; |
| struct socket socket; |
| struct socket_wq wq; |
| |
| int vnet_hdr_sz; |
| |
| #ifdef TUN_DEBUG |
| int debug; |
| #endif |
| }; |
| |
| struct tun_sock { |
| struct sock sk; |
| struct tun_struct *tun; |
| }; |
| |
| static inline struct tun_sock *tun_sk(struct sock *sk) |
| { |
| return container_of(sk, struct tun_sock, sk); |
| } |
| |
| static int tun_attach(struct tun_struct *tun, struct file *file) |
| { |
| struct tun_file *tfile = file->private_data; |
| int err; |
| |
| ASSERT_RTNL(); |
| |
| netif_tx_lock_bh(tun->dev); |
| |
| err = -EINVAL; |
| if (tfile->tun) |
| goto out; |
| |
| err = -EBUSY; |
| if (tun->tfile) |
| goto out; |
| |
| err = 0; |
| tfile->tun = tun; |
| tun->tfile = tfile; |
| tun->socket.file = file; |
| netif_carrier_on(tun->dev); |
| dev_hold(tun->dev); |
| sock_hold(tun->socket.sk); |
| atomic_inc(&tfile->count); |
| |
| out: |
| netif_tx_unlock_bh(tun->dev); |
| return err; |
| } |
| |
| static void __tun_detach(struct tun_struct *tun) |
| { |
| /* Detach from net device */ |
| netif_tx_lock_bh(tun->dev); |
| netif_carrier_off(tun->dev); |
| tun->tfile = NULL; |
| tun->socket.file = NULL; |
| netif_tx_unlock_bh(tun->dev); |
| |
| /* Drop read queue */ |
| skb_queue_purge(&tun->socket.sk->sk_receive_queue); |
| |
| /* Drop the extra count on the net device */ |
| dev_put(tun->dev); |
| } |
| |
| static void tun_detach(struct tun_struct *tun) |
| { |
| rtnl_lock(); |
| __tun_detach(tun); |
| rtnl_unlock(); |
| } |
| |
| static struct tun_struct *__tun_get(struct tun_file *tfile) |
| { |
| struct tun_struct *tun = NULL; |
| |
| if (atomic_inc_not_zero(&tfile->count)) |
| tun = tfile->tun; |
| |
| return tun; |
| } |
| |
| static struct tun_struct *tun_get(struct file *file) |
| { |
| return __tun_get(file->private_data); |
| } |
| |
| static void tun_put(struct tun_struct *tun) |
| { |
| struct tun_file *tfile = tun->tfile; |
| |
| if (atomic_dec_and_test(&tfile->count)) |
| tun_detach(tfile->tun); |
| } |
| |
| /* TAP filtering */ |
| static void addr_hash_set(u32 *mask, const u8 *addr) |
| { |
| int n = ether_crc(ETH_ALEN, addr) >> 26; |
| mask[n >> 5] |= (1 << (n & 31)); |
| } |
| |
| static unsigned int addr_hash_test(const u32 *mask, const u8 *addr) |
| { |
| int n = ether_crc(ETH_ALEN, addr) >> 26; |
| return mask[n >> 5] & (1 << (n & 31)); |
| } |
| |
| static int update_filter(struct tap_filter *filter, void __user *arg) |
| { |
| struct { u8 u[ETH_ALEN]; } *addr; |
| struct tun_filter uf; |
| int err, alen, n, nexact; |
| |
| if (copy_from_user(&uf, arg, sizeof(uf))) |
| return -EFAULT; |
| |
| if (!uf.count) { |
| /* Disabled */ |
| filter->count = 0; |
| return 0; |
| } |
| |
| alen = ETH_ALEN * uf.count; |
| addr = kmalloc(alen, GFP_KERNEL); |
| if (!addr) |
| return -ENOMEM; |
| |
| if (copy_from_user(addr, arg + sizeof(uf), alen)) { |
| err = -EFAULT; |
| goto done; |
| } |
| |
| /* The filter is updated without holding any locks. Which is |
| * perfectly safe. We disable it first and in the worst |
| * case we'll accept a few undesired packets. */ |
| filter->count = 0; |
| wmb(); |
| |
| /* Use first set of addresses as an exact filter */ |
| for (n = 0; n < uf.count && n < FLT_EXACT_COUNT; n++) |
| memcpy(filter->addr[n], addr[n].u, ETH_ALEN); |
| |
| nexact = n; |
| |
| /* Remaining multicast addresses are hashed, |
| * unicast will leave the filter disabled. */ |
| memset(filter->mask, 0, sizeof(filter->mask)); |
| for (; n < uf.count; n++) { |
| if (!is_multicast_ether_addr(addr[n].u)) { |
| err = 0; /* no filter */ |
| goto done; |
| } |
| addr_hash_set(filter->mask, addr[n].u); |
| } |
| |
| /* For ALLMULTI just set the mask to all ones. |
| * This overrides the mask populated above. */ |
| if ((uf.flags & TUN_FLT_ALLMULTI)) |
| memset(filter->mask, ~0, sizeof(filter->mask)); |
| |
| /* Now enable the filter */ |
| wmb(); |
| filter->count = nexact; |
| |
| /* Return the number of exact filters */ |
| err = nexact; |
| |
| done: |
| kfree(addr); |
| return err; |
| } |
| |
| /* Returns: 0 - drop, !=0 - accept */ |
| static int run_filter(struct tap_filter *filter, const struct sk_buff *skb) |
| { |
| /* Cannot use eth_hdr(skb) here because skb_mac_hdr() is incorrect |
| * at this point. */ |
| struct ethhdr *eh = (struct ethhdr *) skb->data; |
| int i; |
| |
| /* Exact match */ |
| for (i = 0; i < filter->count; i++) |
| if (!compare_ether_addr(eh->h_dest, filter->addr[i])) |
| return 1; |
| |
| /* Inexact match (multicast only) */ |
| if (is_multicast_ether_addr(eh->h_dest)) |
| return addr_hash_test(filter->mask, eh->h_dest); |
| |
| return 0; |
| } |
| |
| /* |
| * Checks whether the packet is accepted or not. |
| * Returns: 0 - drop, !=0 - accept |
| */ |
| static int check_filter(struct tap_filter *filter, const struct sk_buff *skb) |
| { |
| if (!filter->count) |
| return 1; |
| |
| return run_filter(filter, skb); |
| } |
| |
| /* Network device part of the driver */ |
| |
| static const struct ethtool_ops tun_ethtool_ops; |
| |
| /* Net device detach from fd. */ |
| static void tun_net_uninit(struct net_device *dev) |
| { |
| struct tun_struct *tun = netdev_priv(dev); |
| struct tun_file *tfile = tun->tfile; |
| |
| /* Inform the methods they need to stop using the dev. |
| */ |
| if (tfile) { |
| wake_up_all(&tun->wq.wait); |
| if (atomic_dec_and_test(&tfile->count)) |
| __tun_detach(tun); |
| } |
| } |
| |
| static void tun_free_netdev(struct net_device *dev) |
| { |
| struct tun_struct *tun = netdev_priv(dev); |
| |
| sock_put(tun->socket.sk); |
| } |
| |
| /* Net device open. */ |
| static int tun_net_open(struct net_device *dev) |
| { |
| netif_start_queue(dev); |
| return 0; |
| } |
| |
| /* Net device close. */ |
| static int tun_net_close(struct net_device *dev) |
| { |
| netif_stop_queue(dev); |
| return 0; |
| } |
| |
| /* Net device start xmit */ |
| static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev) |
| { |
| struct tun_struct *tun = netdev_priv(dev); |
| |
| tun_debug(KERN_INFO, tun, "tun_net_xmit %d\n", skb->len); |
| |
| /* Drop packet if interface is not attached */ |
| if (!tun->tfile) |
| goto drop; |
| |
| /* Drop if the filter does not like it. |
| * This is a noop if the filter is disabled. |
| * Filter can be enabled only for the TAP devices. */ |
| if (!check_filter(&tun->txflt, skb)) |
| goto drop; |
| |
| if (tun->socket.sk->sk_filter && |
| sk_filter(tun->socket.sk, skb)) |
| goto drop; |
| |
| if (skb_queue_len(&tun->socket.sk->sk_receive_queue) >= dev->tx_queue_len) { |
| if (!(tun->flags & TUN_ONE_QUEUE)) { |
| /* Normal queueing mode. */ |
| /* Packet scheduler handles dropping of further packets. */ |
| netif_stop_queue(dev); |
| |
| /* We won't see all dropped packets individually, so overrun |
| * error is more appropriate. */ |
| dev->stats.tx_fifo_errors++; |
| } else { |
| /* Single queue mode. |
| * Driver handles dropping of all packets itself. */ |
| goto drop; |
| } |
| } |
| |
| /* Orphan the skb - required as we might hang on to it |
| * for indefinite time. */ |
| skb_orphan(skb); |
| |
| /* Enqueue packet */ |
| skb_queue_tail(&tun->socket.sk->sk_receive_queue, skb); |
| |
| /* Notify and wake up reader process */ |
| if (tun->flags & TUN_FASYNC) |
| kill_fasync(&tun->fasync, SIGIO, POLL_IN); |
| wake_up_interruptible_poll(&tun->wq.wait, POLLIN | |
| POLLRDNORM | POLLRDBAND); |
| return NETDEV_TX_OK; |
| |
| drop: |
| dev->stats.tx_dropped++; |
| kfree_skb(skb); |
| return NETDEV_TX_OK; |
| } |
| |
| static void tun_net_mclist(struct net_device *dev) |
| { |
| /* |
| * This callback is supposed to deal with mc filter in |
| * _rx_ path and has nothing to do with the _tx_ path. |
| * In rx path we always accept everything userspace gives us. |
| */ |
| } |
| |
| #define MIN_MTU 68 |
| #define MAX_MTU 65535 |
| |
| static int |
| tun_net_change_mtu(struct net_device *dev, int new_mtu) |
| { |
| if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU) |
| return -EINVAL; |
| dev->mtu = new_mtu; |
| return 0; |
| } |
| |
| static u32 tun_net_fix_features(struct net_device *dev, u32 features) |
| { |
| struct tun_struct *tun = netdev_priv(dev); |
| |
| return (features & tun->set_features) | (features & ~TUN_USER_FEATURES); |
| } |
| |
| static const struct net_device_ops tun_netdev_ops = { |
| .ndo_uninit = tun_net_uninit, |
| .ndo_open = tun_net_open, |
| .ndo_stop = tun_net_close, |
| .ndo_start_xmit = tun_net_xmit, |
| .ndo_change_mtu = tun_net_change_mtu, |
| .ndo_fix_features = tun_net_fix_features, |
| }; |
| |
| static const struct net_device_ops tap_netdev_ops = { |
| .ndo_uninit = tun_net_uninit, |
| .ndo_open = tun_net_open, |
| .ndo_stop = tun_net_close, |
| .ndo_start_xmit = tun_net_xmit, |
| .ndo_change_mtu = tun_net_change_mtu, |
| .ndo_fix_features = tun_net_fix_features, |
| .ndo_set_multicast_list = tun_net_mclist, |
| .ndo_set_mac_address = eth_mac_addr, |
| .ndo_validate_addr = eth_validate_addr, |
| }; |
| |
| /* Initialize net device. */ |
| static void tun_net_init(struct net_device *dev) |
| { |
| struct tun_struct *tun = netdev_priv(dev); |
| |
| switch (tun->flags & TUN_TYPE_MASK) { |
| case TUN_TUN_DEV: |
| dev->netdev_ops = &tun_netdev_ops; |
| |
| /* Point-to-Point TUN Device */ |
| dev->hard_header_len = 0; |
| dev->addr_len = 0; |
| dev->mtu = 1500; |
| |
| /* Zero header length */ |
| dev->type = ARPHRD_NONE; |
| dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST; |
| dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */ |
| break; |
| |
| case TUN_TAP_DEV: |
| dev->netdev_ops = &tap_netdev_ops; |
| /* Ethernet TAP Device */ |
| ether_setup(dev); |
| |
| random_ether_addr(dev->dev_addr); |
| |
| dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */ |
| break; |
| } |
| } |
| |
| /* Character device part */ |
| |
| /* Poll */ |
| static unsigned int tun_chr_poll(struct file *file, poll_table * wait) |
| { |
| struct tun_file *tfile = file->private_data; |
| struct tun_struct *tun = __tun_get(tfile); |
| struct sock *sk; |
| unsigned int mask = 0; |
| |
| if (!tun) |
| return POLLERR; |
| |
| sk = tun->socket.sk; |
| |
| tun_debug(KERN_INFO, tun, "tun_chr_poll\n"); |
| |
| poll_wait(file, &tun->wq.wait, wait); |
| |
| if (!skb_queue_empty(&sk->sk_receive_queue)) |
| mask |= POLLIN | POLLRDNORM; |
| |
| if (sock_writeable(sk) || |
| (!test_and_set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags) && |
| sock_writeable(sk))) |
| mask |= POLLOUT | POLLWRNORM; |
| |
| if (tun->dev->reg_state != NETREG_REGISTERED) |
| mask = POLLERR; |
| |
| tun_put(tun); |
| return mask; |
| } |
| |
| /* prepad is the amount to reserve at front. len is length after that. |
| * linear is a hint as to how much to copy (usually headers). */ |
| static struct sk_buff *tun_alloc_skb(struct tun_struct *tun, |
| size_t prepad, size_t len, |
| size_t linear, int noblock) |
| { |
| struct sock *sk = tun->socket.sk; |
| struct sk_buff *skb; |
| int err; |
| |
| sock_update_classid(sk); |
| |
| /* Under a page? Don't bother with paged skb. */ |
| if (prepad + len < PAGE_SIZE || !linear) |
| linear = len; |
| |
| skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock, |
| &err); |
| if (!skb) |
| return ERR_PTR(err); |
| |
| skb_reserve(skb, prepad); |
| skb_put(skb, linear); |
| skb->data_len = len - linear; |
| skb->len += len - linear; |
| |
| return skb; |
| } |
| |
| /* Get packet from user space buffer */ |
| static ssize_t tun_get_user(struct tun_struct *tun, |
| const struct iovec *iv, size_t count, |
| int noblock) |
| { |
| struct tun_pi pi = { 0, cpu_to_be16(ETH_P_IP) }; |
| struct sk_buff *skb; |
| size_t len = count, align = NET_SKB_PAD; |
| struct virtio_net_hdr gso = { 0 }; |
| int offset = 0; |
| |
| if (!(tun->flags & TUN_NO_PI)) { |
| if ((len -= sizeof(pi)) > count) |
| return -EINVAL; |
| |
| if (memcpy_fromiovecend((void *)&pi, iv, 0, sizeof(pi))) |
| return -EFAULT; |
| offset += sizeof(pi); |
| } |
| |
| if (tun->flags & TUN_VNET_HDR) { |
| if ((len -= tun->vnet_hdr_sz) > count) |
| return -EINVAL; |
| |
| if (memcpy_fromiovecend((void *)&gso, iv, offset, sizeof(gso))) |
| return -EFAULT; |
| |
| if ((gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && |
| gso.csum_start + gso.csum_offset + 2 > gso.hdr_len) |
| gso.hdr_len = gso.csum_start + gso.csum_offset + 2; |
| |
| if (gso.hdr_len > len) |
| return -EINVAL; |
| offset += tun->vnet_hdr_sz; |
| } |
| |
| if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) { |
| align += NET_IP_ALIGN; |
| if (unlikely(len < ETH_HLEN || |
| (gso.hdr_len && gso.hdr_len < ETH_HLEN))) |
| return -EINVAL; |
| } |
| |
| skb = tun_alloc_skb(tun, align, len, gso.hdr_len, noblock); |
| if (IS_ERR(skb)) { |
| if (PTR_ERR(skb) != -EAGAIN) |
| tun->dev->stats.rx_dropped++; |
| return PTR_ERR(skb); |
| } |
| |
| if (skb_copy_datagram_from_iovec(skb, 0, iv, offset, len)) { |
| tun->dev->stats.rx_dropped++; |
| kfree_skb(skb); |
| return -EFAULT; |
| } |
| |
| if (gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { |
| if (!skb_partial_csum_set(skb, gso.csum_start, |
| gso.csum_offset)) { |
| tun->dev->stats.rx_frame_errors++; |
| kfree_skb(skb); |
| return -EINVAL; |
| } |
| } |
| |
| switch (tun->flags & TUN_TYPE_MASK) { |
| case TUN_TUN_DEV: |
| if (tun->flags & TUN_NO_PI) { |
| switch (skb->data[0] & 0xf0) { |
| case 0x40: |
| pi.proto = htons(ETH_P_IP); |
| break; |
| case 0x60: |
| pi.proto = htons(ETH_P_IPV6); |
| break; |
| default: |
| tun->dev->stats.rx_dropped++; |
| kfree_skb(skb); |
| return -EINVAL; |
| } |
| } |
| |
| skb_reset_mac_header(skb); |
| skb->protocol = pi.proto; |
| skb->dev = tun->dev; |
| break; |
| case TUN_TAP_DEV: |
| skb->protocol = eth_type_trans(skb, tun->dev); |
| break; |
| } |
| |
| 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; |
| case VIRTIO_NET_HDR_GSO_UDP: |
| skb_shinfo(skb)->gso_type = SKB_GSO_UDP; |
| 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->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 file *file = iocb->ki_filp; |
| struct tun_struct *tun = tun_get(file); |
| ssize_t result; |
| |
| if (!tun) |
| return -EBADFD; |
| |
| tun_debug(KERN_INFO, tun, "tun_chr_write %ld\n", count); |
| |
| result = tun_get_user(tun, iv, iov_length(iv, count), |
| file->f_flags & O_NONBLOCK); |
| |
| tun_put(tun); |
| return result; |
| } |
| |
| /* Put packet to the user space buffer */ |
| static ssize_t tun_put_user(struct tun_struct *tun, |
| struct sk_buff *skb, |
| const 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_toiovecend(iv, (void *) &pi, 0, sizeof(pi))) |
| return -EFAULT; |
| total += sizeof(pi); |
| } |
| |
| if (tun->flags & TUN_VNET_HDR) { |
| struct virtio_net_hdr gso = { 0 }; /* no info leak */ |
| if ((len -= tun->vnet_hdr_sz) < 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 if (sinfo->gso_type & SKB_GSO_UDP) |
| gso.gso_type = VIRTIO_NET_HDR_GSO_UDP; |
| else { |
| pr_err("unexpected GSO type: " |
| "0x%x, gso_size %d, hdr_len %d\n", |
| sinfo->gso_type, gso.gso_size, |
| gso.hdr_len); |
| print_hex_dump(KERN_ERR, "tun: ", |
| DUMP_PREFIX_NONE, |
| 16, 1, skb->head, |
| min((int)gso.hdr_len, 64), true); |
| WARN_ON_ONCE(1); |
| return -EINVAL; |
| } |
| 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_checksum_start_offset(skb); |
| gso.csum_offset = skb->csum_offset; |
| } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) { |
| gso.flags = VIRTIO_NET_HDR_F_DATA_VALID; |
| } /* else everything is zero */ |
| |
| if (unlikely(memcpy_toiovecend(iv, (void *)&gso, total, |
| sizeof(gso)))) |
| return -EFAULT; |
| total += tun->vnet_hdr_sz; |
| } |
| |
| len = min_t(int, skb->len, len); |
| |
| skb_copy_datagram_const_iovec(skb, 0, iv, total, len); |
| total += skb->len; |
| |
| tun->dev->stats.tx_packets++; |
| tun->dev->stats.tx_bytes += len; |
| |
| return total; |
| } |
| |
| static ssize_t tun_do_read(struct tun_struct *tun, |
| struct kiocb *iocb, const struct iovec *iv, |
| ssize_t len, int noblock) |
| { |
| DECLARE_WAITQUEUE(wait, current); |
| struct sk_buff *skb; |
| ssize_t ret = 0; |
| |
| tun_debug(KERN_INFO, tun, "tun_chr_read\n"); |
| |
| if (unlikely(!noblock)) |
| add_wait_queue(&tun->wq.wait, &wait); |
| while (len) { |
| current->state = TASK_INTERRUPTIBLE; |
| |
| /* Read frames from the queue */ |
| if (!(skb=skb_dequeue(&tun->socket.sk->sk_receive_queue))) { |
| if (noblock) { |
| ret = -EAGAIN; |
| break; |
| } |
| if (signal_pending(current)) { |
| ret = -ERESTARTSYS; |
| break; |
| } |
| if (tun->dev->reg_state != NETREG_REGISTERED) { |
| ret = -EIO; |
| break; |
| } |
| |
| /* Nothing to read, let's sleep */ |
| schedule(); |
| continue; |
| } |
| netif_wake_queue(tun->dev); |
| |
| ret = tun_put_user(tun, skb, iv, len); |
| kfree_skb(skb); |
| break; |
| } |
| |
| current->state = TASK_RUNNING; |
| if (unlikely(!noblock)) |
| remove_wait_queue(&tun->wq.wait, &wait); |
| |
| return ret; |
| } |
| |
| 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_file *tfile = file->private_data; |
| struct tun_struct *tun = __tun_get(tfile); |
| ssize_t len, ret; |
| |
| if (!tun) |
| return -EBADFD; |
| len = iov_length(iv, count); |
| if (len < 0) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| ret = tun_do_read(tun, iocb, iv, len, file->f_flags & O_NONBLOCK); |
| ret = min_t(ssize_t, ret, len); |
| out: |
| tun_put(tun); |
| return ret; |
| } |
| |
| static void tun_setup(struct net_device *dev) |
| { |
| struct tun_struct *tun = netdev_priv(dev); |
| |
| tun->owner = -1; |
| tun->group = -1; |
| |
| dev->ethtool_ops = &tun_ethtool_ops; |
| dev->destructor = tun_free_netdev; |
| } |
| |
| /* Trivial set of netlink ops to allow deleting tun or tap |
| * device with netlink. |
| */ |
| static int tun_validate(struct nlattr *tb[], struct nlattr *data[]) |
| { |
| return -EINVAL; |
| } |
| |
| static struct rtnl_link_ops tun_link_ops __read_mostly = { |
| .kind = DRV_NAME, |
| .priv_size = sizeof(struct tun_struct), |
| .setup = tun_setup, |
| .validate = tun_validate, |
| }; |
| |
| static void tun_sock_write_space(struct sock *sk) |
| { |
| struct tun_struct *tun; |
| wait_queue_head_t *wqueue; |
| |
| if (!sock_writeable(sk)) |
| return; |
| |
| if (!test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags)) |
| return; |
| |
| wqueue = sk_sleep(sk); |
| if (wqueue && waitqueue_active(wqueue)) |
| wake_up_interruptible_sync_poll(wqueue, POLLOUT | |
| POLLWRNORM | POLLWRBAND); |
| |
| tun = tun_sk(sk)->tun; |
| kill_fasync(&tun->fasync, SIGIO, POLL_OUT); |
| } |
| |
| static void tun_sock_destruct(struct sock *sk) |
| { |
| free_netdev(tun_sk(sk)->tun->dev); |
| } |
| |
| static int tun_sendmsg(struct kiocb *iocb, struct socket *sock, |
| struct msghdr *m, size_t total_len) |
| { |
| struct tun_struct *tun = container_of(sock, struct tun_struct, socket); |
| return tun_get_user(tun, m->msg_iov, total_len, |
| m->msg_flags & MSG_DONTWAIT); |
| } |
| |
| static int tun_recvmsg(struct kiocb *iocb, struct socket *sock, |
| struct msghdr *m, size_t total_len, |
| int flags) |
| { |
| struct tun_struct *tun = container_of(sock, struct tun_struct, socket); |
| int ret; |
| if (flags & ~(MSG_DONTWAIT|MSG_TRUNC)) |
| return -EINVAL; |
| ret = tun_do_read(tun, iocb, m->msg_iov, total_len, |
| flags & MSG_DONTWAIT); |
| if (ret > total_len) { |
| m->msg_flags |= MSG_TRUNC; |
| ret = flags & MSG_TRUNC ? ret : total_len; |
| } |
| return ret; |
| } |
| |
| /* Ops structure to mimic raw sockets with tun */ |
| static const struct proto_ops tun_socket_ops = { |
| .sendmsg = tun_sendmsg, |
| .recvmsg = tun_recvmsg, |
| }; |
| |
| static struct proto tun_proto = { |
| .name = "tun", |
| .owner = THIS_MODULE, |
| .obj_size = sizeof(struct tun_sock), |
| }; |
| |
| static int tun_flags(struct tun_struct *tun) |
| { |
| int flags = 0; |
| |
| if (tun->flags & TUN_TUN_DEV) |
| flags |= IFF_TUN; |
| else |
| flags |= IFF_TAP; |
| |
| if (tun->flags & TUN_NO_PI) |
| flags |= IFF_NO_PI; |
| |
| if (tun->flags & TUN_ONE_QUEUE) |
| flags |= IFF_ONE_QUEUE; |
| |
| if (tun->flags & TUN_VNET_HDR) |
| flags |= IFF_VNET_HDR; |
| |
| return flags; |
| } |
| |
| static ssize_t tun_show_flags(struct device *dev, struct device_attribute *attr, |
| char *buf) |
| { |
| struct tun_struct *tun = netdev_priv(to_net_dev(dev)); |
| return sprintf(buf, "0x%x\n", tun_flags(tun)); |
| } |
| |
| static ssize_t tun_show_owner(struct device *dev, struct device_attribute *attr, |
| char *buf) |
| { |
| struct tun_struct *tun = netdev_priv(to_net_dev(dev)); |
| return sprintf(buf, "%d\n", tun->owner); |
| } |
| |
| static ssize_t tun_show_group(struct device *dev, struct device_attribute *attr, |
| char *buf) |
| { |
| struct tun_struct *tun = netdev_priv(to_net_dev(dev)); |
| return sprintf(buf, "%d\n", tun->group); |
| } |
| |
| static DEVICE_ATTR(tun_flags, 0444, tun_show_flags, NULL); |
| static DEVICE_ATTR(owner, 0444, tun_show_owner, NULL); |
| static DEVICE_ATTR(group, 0444, tun_show_group, NULL); |
| |
| static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) |
| { |
| struct sock *sk; |
| struct tun_struct *tun; |
| struct net_device *dev; |
| int err; |
| |
| dev = __dev_get_by_name(net, ifr->ifr_name); |
| if (dev) { |
| const struct cred *cred = current_cred(); |
| |
| if (ifr->ifr_flags & IFF_TUN_EXCL) |
| return -EBUSY; |
| if ((ifr->ifr_flags & IFF_TUN) && dev->netdev_ops == &tun_netdev_ops) |
| tun = netdev_priv(dev); |
| else if ((ifr->ifr_flags & IFF_TAP) && dev->netdev_ops == &tap_netdev_ops) |
| tun = netdev_priv(dev); |
| else |
| return -EINVAL; |
| |
| if (((tun->owner != -1 && cred->euid != tun->owner) || |
| (tun->group != -1 && !in_egroup_p(tun->group))) && |
| !capable(CAP_NET_ADMIN)) |
| return -EPERM; |
| err = security_tun_dev_attach(tun->socket.sk); |
| if (err < 0) |
| return err; |
| |
| err = tun_attach(tun, file); |
| if (err < 0) |
| return err; |
| } |
| else { |
| char *name; |
| unsigned long flags = 0; |
| |
| if (!capable(CAP_NET_ADMIN)) |
| return -EPERM; |
| err = security_tun_dev_create(); |
| if (err < 0) |
| return err; |
| |
| /* 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 |
| return -EINVAL; |
| |
| 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); |
| dev->rtnl_link_ops = &tun_link_ops; |
| |
| tun = netdev_priv(dev); |
| tun->dev = dev; |
| tun->flags = flags; |
| tun->txflt.count = 0; |
| tun->vnet_hdr_sz = sizeof(struct virtio_net_hdr); |
| |
| err = -ENOMEM; |
| sk = sk_alloc(net, AF_UNSPEC, GFP_KERNEL, &tun_proto); |
| if (!sk) |
| goto err_free_dev; |
| |
| tun->socket.wq = &tun->wq; |
| init_waitqueue_head(&tun->wq.wait); |
| tun->socket.ops = &tun_socket_ops; |
| sock_init_data(&tun->socket, sk); |
| sk->sk_write_space = tun_sock_write_space; |
| sk->sk_sndbuf = INT_MAX; |
| |
| tun_sk(sk)->tun = tun; |
| |
| security_tun_dev_post_create(sk); |
| |
| tun_net_init(dev); |
| |
| dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST | |
| TUN_USER_FEATURES; |
| dev->features = dev->hw_features; |
| |
| err = register_netdevice(tun->dev); |
| if (err < 0) |
| goto err_free_sk; |
| |
| if (device_create_file(&tun->dev->dev, &dev_attr_tun_flags) || |
| device_create_file(&tun->dev->dev, &dev_attr_owner) || |
| device_create_file(&tun->dev->dev, &dev_attr_group)) |
| pr_err("Failed to create tun sysfs files\n"); |
| |
| sk->sk_destruct = tun_sock_destruct; |
| |
| err = tun_attach(tun, file); |
| if (err < 0) |
| goto failed; |
| } |
| |
| tun_debug(KERN_INFO, tun, "tun_set_iff\n"); |
| |
| 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; |
| |
| /* 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_sk: |
| sock_put(sk); |
| err_free_dev: |
| free_netdev(dev); |
| failed: |
| return err; |
| } |
| |
| static int tun_get_iff(struct net *net, struct tun_struct *tun, |
| struct ifreq *ifr) |
| { |
| tun_debug(KERN_INFO, tun, "tun_get_iff\n"); |
| |
| strcpy(ifr->ifr_name, tun->dev->name); |
| |
| ifr->ifr_flags = tun_flags(tun); |
| |
| return 0; |
| } |
| |
| /* This is like a cut-down ethtool ops, except done via tun fd so no |
| * privs required. */ |
| static int set_offload(struct tun_struct *tun, unsigned long arg) |
| { |
| u32 features = 0; |
| |
| if (arg & TUN_F_CSUM) { |
| features |= NETIF_F_HW_CSUM; |
| 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); |
| } |
| |
| if (arg & TUN_F_UFO) { |
| features |= NETIF_F_UFO; |
| arg &= ~TUN_F_UFO; |
| } |
| } |
| |
| /* This gives the user a way to test for new features in future by |
| * trying to set them. */ |
| if (arg) |
| return -EINVAL; |
| |
| tun->set_features = features; |
| netdev_update_features(tun->dev); |
| |
| return 0; |
| } |
| |
| static long __tun_chr_ioctl(struct file *file, unsigned int cmd, |
| unsigned long arg, int ifreq_len) |
| { |
| struct tun_file *tfile = file->private_data; |
| struct tun_struct *tun; |
| void __user* argp = (void __user*)arg; |
| struct sock_fprog fprog; |
| struct ifreq ifr; |
| int sndbuf; |
| int vnet_hdr_sz; |
| int ret; |
| |
| if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89) |
| if (copy_from_user(&ifr, argp, ifreq_len)) |
| return -EFAULT; |
| |
| 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); |
| } |
| |
| rtnl_lock(); |
| |
| tun = __tun_get(tfile); |
| if (cmd == TUNSETIFF && !tun) { |
| ifr.ifr_name[IFNAMSIZ-1] = '\0'; |
| |
| ret = tun_set_iff(tfile->net, file, &ifr); |
| |
| if (ret) |
| goto unlock; |
| |
| if (copy_to_user(argp, &ifr, ifreq_len)) |
| ret = -EFAULT; |
| goto unlock; |
| } |
| |
| ret = -EBADFD; |
| if (!tun) |
| goto unlock; |
| |
| tun_debug(KERN_INFO, tun, "tun_chr_ioctl cmd %d\n", cmd); |
| |
| ret = 0; |
| switch (cmd) { |
| case TUNGETIFF: |
| ret = tun_get_iff(current->nsproxy->net_ns, tun, &ifr); |
| if (ret) |
| break; |
| |
| if (copy_to_user(argp, &ifr, ifreq_len)) |
| ret = -EFAULT; |
| break; |
| |
| case TUNSETNOCSUM: |
| /* Disable/Enable checksum */ |
| |
| /* [unimplemented] */ |
| tun_debug(KERN_INFO, tun, "ignored: set checksum %s\n", |
| arg ? "disabled" : "enabled"); |
| break; |
| |
| case TUNSETPERSIST: |
| /* Disable/Enable persist mode */ |
| if (arg) |
| tun->flags |= TUN_PERSIST; |
| else |
| tun->flags &= ~TUN_PERSIST; |
| |
| tun_debug(KERN_INFO, tun, "persist %s\n", |
| arg ? "enabled" : "disabled"); |
| break; |
| |
| case TUNSETOWNER: |
| /* Set owner of the device */ |
| tun->owner = (uid_t) arg; |
| |
| tun_debug(KERN_INFO, tun, "owner set to %d\n", tun->owner); |
| break; |
| |
| case TUNSETGROUP: |
| /* Set group of the device */ |
| tun->group= (gid_t) arg; |
| |
| tun_debug(KERN_INFO, tun, "group set to %d\n", tun->group); |
| break; |
| |
| case TUNSETLINK: |
| /* Only allow setting the type when the interface is down */ |
| if (tun->dev->flags & IFF_UP) { |
| tun_debug(KERN_INFO, tun, |
| "Linktype set failed because interface is up\n"); |
| ret = -EBUSY; |
| } else { |
| tun->dev->type = (int) arg; |
| tun_debug(KERN_INFO, tun, "linktype set to %d\n", |
| tun->dev->type); |
| ret = 0; |
| } |
| break; |
| |
| #ifdef TUN_DEBUG |
| case TUNSETDEBUG: |
| tun->debug = arg; |
| break; |
| #endif |
| case TUNSETOFFLOAD: |
| ret = set_offload(tun, arg); |
| break; |
| |
| case TUNSETTXFILTER: |
| /* Can be set only for TAPs */ |
| ret = -EINVAL; |
| if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV) |
| break; |
| ret = update_filter(&tun->txflt, (void __user *)arg); |
| break; |
| |
| case SIOCGIFHWADDR: |
| /* Get hw address */ |
| 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, ifreq_len)) |
| ret = -EFAULT; |
| break; |
| |
| case SIOCSIFHWADDR: |
| /* Set hw address */ |
| tun_debug(KERN_DEBUG, tun, "set hw address: %pM\n", |
| ifr.ifr_hwaddr.sa_data); |
| |
| ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr); |
| break; |
| |
| case TUNGETSNDBUF: |
| sndbuf = tun->socket.sk->sk_sndbuf; |
| if (copy_to_user(argp, &sndbuf, sizeof(sndbuf))) |
| ret = -EFAULT; |
| break; |
| |
| case TUNSETSNDBUF: |
| if (copy_from_user(&sndbuf, argp, sizeof(sndbuf))) { |
| ret = -EFAULT; |
| break; |
| } |
| |
| tun->socket.sk->sk_sndbuf = sndbuf; |
| break; |
| |
| case TUNGETVNETHDRSZ: |
| vnet_hdr_sz = tun->vnet_hdr_sz; |
| if (copy_to_user(argp, &vnet_hdr_sz, sizeof(vnet_hdr_sz))) |
| ret = -EFAULT; |
| break; |
| |
| case TUNSETVNETHDRSZ: |
| if (copy_from_user(&vnet_hdr_sz, argp, sizeof(vnet_hdr_sz))) { |
| ret = -EFAULT; |
| break; |
| } |
| if (vnet_hdr_sz < (int)sizeof(struct virtio_net_hdr)) { |
| ret = -EINVAL; |
| break; |
| } |
| |
| tun->vnet_hdr_sz = vnet_hdr_sz; |
| break; |
| |
| case TUNATTACHFILTER: |
| /* Can be set only for TAPs */ |
| ret = -EINVAL; |
| if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV) |
| break; |
| ret = -EFAULT; |
| if (copy_from_user(&fprog, argp, sizeof(fprog))) |
| break; |
| |
| ret = sk_attach_filter(&fprog, tun->socket.sk); |
| break; |
| |
| case TUNDETACHFILTER: |
| /* Can be set only for TAPs */ |
| ret = -EINVAL; |
| if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV) |
| break; |
| ret = sk_detach_filter(tun->socket.sk); |
| break; |
| |
| default: |
| ret = -EINVAL; |
| break; |
| } |
| |
| unlock: |
| rtnl_unlock(); |
| if (tun) |
| tun_put(tun); |
| return ret; |
| } |
| |
| static long tun_chr_ioctl(struct file *file, |
| unsigned int cmd, unsigned long arg) |
| { |
| return __tun_chr_ioctl(file, cmd, arg, sizeof (struct ifreq)); |
| } |
| |
| #ifdef CONFIG_COMPAT |
| static long tun_chr_compat_ioctl(struct file *file, |
| unsigned int cmd, unsigned long arg) |
| { |
| switch (cmd) { |
| case TUNSETIFF: |
| case TUNGETIFF: |
| case TUNSETTXFILTER: |
| case TUNGETSNDBUF: |
| case TUNSETSNDBUF: |
| case SIOCGIFHWADDR: |
| case SIOCSIFHWADDR: |
| arg = (unsigned long)compat_ptr(arg); |
| break; |
| default: |
| arg = (compat_ulong_t)arg; |
| break; |
| } |
| |
| /* |
| * compat_ifreq is shorter than ifreq, so we must not access beyond |
| * the end of that structure. All fields that are used in this |
| * driver are compatible though, we don't need to convert the |
| * contents. |
| */ |
| return __tun_chr_ioctl(file, cmd, arg, sizeof(struct compat_ifreq)); |
| } |
| #endif /* CONFIG_COMPAT */ |
| |
| static int tun_chr_fasync(int fd, struct file *file, int on) |
| { |
| struct tun_struct *tun = tun_get(file); |
| int ret; |
| |
| if (!tun) |
| return -EBADFD; |
| |
| tun_debug(KERN_INFO, tun, "tun_chr_fasync %d\n", on); |
| |
| 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: |
| tun_put(tun); |
| return ret; |
| } |
| |
| static int tun_chr_open(struct inode *inode, struct file * file) |
| { |
| struct tun_file *tfile; |
| |
| DBG1(KERN_INFO, "tunX: tun_chr_open\n"); |
| |
| tfile = kmalloc(sizeof(*tfile), GFP_KERNEL); |
| if (!tfile) |
| return -ENOMEM; |
| atomic_set(&tfile->count, 0); |
| tfile->tun = NULL; |
| tfile->net = get_net(current->nsproxy->net_ns); |
| file->private_data = tfile; |
| return 0; |
| } |
| |
| static int tun_chr_close(struct inode *inode, struct file *file) |
| { |
| struct tun_file *tfile = file->private_data; |
| struct tun_struct *tun; |
| |
| tun = __tun_get(tfile); |
| if (tun) { |
| struct net_device *dev = tun->dev; |
| |
| tun_debug(KERN_INFO, tun, "tun_chr_close\n"); |
| |
| __tun_detach(tun); |
| |
| /* If desirable, unregister the netdevice. */ |
| if (!(tun->flags & TUN_PERSIST)) { |
| rtnl_lock(); |
| if (dev->reg_state == NETREG_REGISTERED) |
| unregister_netdevice(dev); |
| rtnl_unlock(); |
| } |
| } |
| |
| tun = tfile->tun; |
| if (tun) |
| sock_put(tun->socket.sk); |
| |
| put_net(tfile->net); |
| kfree(tfile); |
| |
| 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, |
| .unlocked_ioctl = tun_chr_ioctl, |
| #ifdef CONFIG_COMPAT |
| .compat_ioctl = tun_chr_compat_ioctl, |
| #endif |
| .open = tun_chr_open, |
| .release = tun_chr_close, |
| .fasync = tun_chr_fasync |
| }; |
| |
| static struct miscdevice tun_miscdev = { |
| .minor = TUN_MINOR, |
| .name = "tun", |
| .nodename = "net/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; |
| ethtool_cmd_speed_set(cmd, 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 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 = ethtool_op_get_link, |
| }; |
| |
| |
| static int __init tun_init(void) |
| { |
| int ret = 0; |
| |
| pr_info("%s, %s\n", DRV_DESCRIPTION, DRV_VERSION); |
| pr_info("%s\n", DRV_COPYRIGHT); |
| |
| ret = rtnl_link_register(&tun_link_ops); |
| if (ret) { |
| pr_err("Can't register link_ops\n"); |
| goto err_linkops; |
| } |
| |
| ret = misc_register(&tun_miscdev); |
| if (ret) { |
| pr_err("Can't register misc device %d\n", TUN_MINOR); |
| goto err_misc; |
| } |
| return 0; |
| err_misc: |
| rtnl_link_unregister(&tun_link_ops); |
| err_linkops: |
| return ret; |
| } |
| |
| static void tun_cleanup(void) |
| { |
| misc_deregister(&tun_miscdev); |
| rtnl_link_unregister(&tun_link_ops); |
| } |
| |
| /* Get an underlying socket object from tun file. Returns error unless file is |
| * attached to a device. The returned object works like a packet socket, it |
| * can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for |
| * holding a reference to the file for as long as the socket is in use. */ |
| struct socket *tun_get_socket(struct file *file) |
| { |
| struct tun_struct *tun; |
| if (file->f_op != &tun_fops) |
| return ERR_PTR(-EINVAL); |
| tun = tun_get(file); |
| if (!tun) |
| return ERR_PTR(-EBADFD); |
| tun_put(tun); |
| return &tun->socket; |
| } |
| EXPORT_SYMBOL_GPL(tun_get_socket); |
| |
| module_init(tun_init); |
| module_exit(tun_cleanup); |
| MODULE_DESCRIPTION(DRV_DESCRIPTION); |
| MODULE_AUTHOR(DRV_COPYRIGHT); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS_MISCDEV(TUN_MINOR); |
| MODULE_ALIAS("devname:net/tun"); |