| /* |
| * 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 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/smp_lock.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/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 <net/net_namespace.h> |
| #include <net/netns/generic.h> |
| |
| #include <asm/system.h> |
| #include <asm/uaccess.h> |
| |
| /* Uncomment to enable debugging */ |
| /* #define TUN_DEBUG 1 */ |
| |
| #ifdef TUN_DEBUG |
| static int debug; |
| |
| #define DBG if(tun->debug)printk |
| #define DBG1 if(debug==2)printk |
| #else |
| #define DBG( a... ) |
| #define DBG1( a... ) |
| #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_struct { |
| struct list_head list; |
| unsigned int flags; |
| int attached; |
| uid_t owner; |
| gid_t group; |
| |
| wait_queue_head_t read_wait; |
| struct sk_buff_head readq; |
| |
| struct net_device *dev; |
| struct fasync_struct *fasync; |
| |
| struct tap_filter txflt; |
| |
| #ifdef TUN_DEBUG |
| int debug; |
| #endif |
| }; |
| |
| /* TAP filterting */ |
| 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; |
| |
| /* The rest is hashed */ |
| memset(filter->mask, 0, sizeof(filter->mask)); |
| for (; n < uf.count; n++) |
| 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 unsigned int tun_net_id; |
| struct tun_net { |
| struct list_head dev_list; |
| }; |
| |
| static const struct ethtool_ops tun_ethtool_ops; |
| |
| /* 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 int tun_net_xmit(struct sk_buff *skb, struct net_device *dev) |
| { |
| struct tun_struct *tun = netdev_priv(dev); |
| |
| DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->dev->name, skb->len); |
| |
| /* Drop packet if interface is not attached */ |
| if (!tun->attached) |
| 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 (skb_queue_len(&tun->readq) >= 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; |
| } |
| } |
| |
| /* Enqueue packet */ |
| skb_queue_tail(&tun->readq, skb); |
| dev->trans_start = jiffies; |
| |
| /* Notify and wake up reader process */ |
| if (tun->flags & TUN_FASYNC) |
| kill_fasync(&tun->fasync, SIGIO, POLL_IN); |
| wake_up_interruptible(&tun->read_wait); |
| return 0; |
| |
| drop: |
| dev->stats.tx_dropped++; |
| kfree_skb(skb); |
| return 0; |
| } |
| |
| 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. |
| */ |
| return; |
| } |
| |
| #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; |
| } |
| |
| /* 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: |
| /* Point-to-Point TUN Device */ |
| dev->hard_header_len = 0; |
| dev->addr_len = 0; |
| dev->mtu = 1500; |
| dev->change_mtu = tun_net_change_mtu; |
| |
| /* 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: |
| /* Ethernet TAP Device */ |
| ether_setup(dev); |
| dev->change_mtu = tun_net_change_mtu; |
| dev->set_multicast_list = tun_net_mclist; |
| |
| 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_struct *tun = file->private_data; |
| unsigned int mask = POLLOUT | POLLWRNORM; |
| |
| if (!tun) |
| return -EBADFD; |
| |
| DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name); |
| |
| poll_wait(file, &tun->read_wait, wait); |
| |
| if (!skb_queue_empty(&tun->readq)) |
| mask |= POLLIN | POLLRDNORM; |
| |
| 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(size_t prepad, size_t len, size_t linear, |
| gfp_t gfp) |
| { |
| struct sk_buff *skb; |
| unsigned int i; |
| |
| skb = alloc_skb(prepad + len, gfp|__GFP_NOWARN); |
| if (skb) { |
| skb_reserve(skb, prepad); |
| skb_put(skb, len); |
| return skb; |
| } |
| |
| /* Under a page? Don't bother with paged skb. */ |
| if (prepad + len < PAGE_SIZE) |
| return NULL; |
| |
| /* Start with a normal skb, and add pages. */ |
| skb = alloc_skb(prepad + linear, gfp); |
| if (!skb) |
| return NULL; |
| |
| skb_reserve(skb, prepad); |
| skb_put(skb, linear); |
| |
| len -= linear; |
| |
| for (i = 0; i < MAX_SKB_FRAGS; i++) { |
| skb_frag_t *f = &skb_shinfo(skb)->frags[i]; |
| |
| f->page = alloc_page(gfp|__GFP_ZERO); |
| if (!f->page) |
| break; |
| |
| f->page_offset = 0; |
| f->size = PAGE_SIZE; |
| |
| skb->data_len += PAGE_SIZE; |
| skb->len += PAGE_SIZE; |
| skb->truesize += PAGE_SIZE; |
| skb_shinfo(skb)->nr_frags++; |
| |
| if (len < PAGE_SIZE) { |
| len = 0; |
| break; |
| } |
| len -= PAGE_SIZE; |
| } |
| |
| /* Too large, or alloc fail? */ |
| if (unlikely(len)) { |
| kfree_skb(skb); |
| skb = NULL; |
| } |
| |
| return skb; |
| } |
| |
| /* Get packet from user space buffer */ |
| static __inline__ ssize_t tun_get_user(struct tun_struct *tun, struct iovec *iv, size_t count) |
| { |
| struct tun_pi pi = { 0, __constant_htons(ETH_P_IP) }; |
| struct sk_buff *skb; |
| size_t len = count, align = 0; |
| struct virtio_net_hdr gso = { 0 }; |
| |
| if (!(tun->flags & TUN_NO_PI)) { |
| if ((len -= sizeof(pi)) > count) |
| return -EINVAL; |
| |
| if(memcpy_fromiovec((void *)&pi, iv, sizeof(pi))) |
| return -EFAULT; |
| } |
| |
| if (tun->flags & TUN_VNET_HDR) { |
| if ((len -= sizeof(gso)) > count) |
| return -EINVAL; |
| |
| if (memcpy_fromiovec((void *)&gso, iv, sizeof(gso))) |
| return -EFAULT; |
| |
| if (gso.hdr_len > len) |
| return -EINVAL; |
| } |
| |
| if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) { |
| align = NET_IP_ALIGN; |
| if (unlikely(len < ETH_HLEN)) |
| return -EINVAL; |
| } |
| |
| if (!(skb = tun_alloc_skb(align, len, gso.hdr_len, GFP_KERNEL))) { |
| tun->dev->stats.rx_dropped++; |
| return -ENOMEM; |
| } |
| |
| if (skb_copy_datagram_from_iovec(skb, 0, iv, 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; |
| } |
| } else if (tun->flags & TUN_NOCHECKSUM) |
| skb->ip_summed = CHECKSUM_UNNECESSARY; |
| |
| 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; |
| 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; |
| const struct cred *cred = current_cred(); |
| 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 && |
| cred->euid != tun->owner) || |
| (tun->group != -1 && |
| cred->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; |
| } |
| |
| static int tun_get_iff(struct net *net, struct file *file, struct ifreq *ifr) |
| { |
| struct tun_struct *tun = file->private_data; |
| |
| if (!tun) |
| return -EBADFD; |
| |
| DBG(KERN_INFO "%s: tun_get_iff\n", tun->dev->name); |
| |
| strcpy(ifr->ifr_name, tun->dev->name); |
| |
| ifr->ifr_flags = 0; |
| |
| if (ifr->ifr_flags & TUN_TUN_DEV) |
| ifr->ifr_flags |= IFF_TUN; |
| else |
| ifr->ifr_flags |= IFF_TAP; |
| |
| if (tun->flags & TUN_NO_PI) |
| ifr->ifr_flags |= IFF_NO_PI; |
| |
| if (tun->flags & TUN_ONE_QUEUE) |
| ifr->ifr_flags |= IFF_ONE_QUEUE; |
| |
| if (tun->flags & TUN_VNET_HDR) |
| ifr->ifr_flags |= IFF_VNET_HDR; |
| |
| return 0; |
| } |
| |
| /* 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 TUNGETIFF: |
| ret = tun_get_iff(current->nsproxy->net_ns, file, &ifr); |
| if (ret) |
| return ret; |
| |
| if (copy_to_user(argp, &ifr, sizeof(ifr))) |
| return -EFAULT; |
| break; |
| |
| 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); |
| |
| 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); |