/* * TUN - Universal TUN/TAP device driver. * Copyright (C) 1999-2002 Maxim Krasnyansky * * 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 2005/08/14 * Add TUNSETLINK ioctl to set the link encapsulation * * Mark Smith * Use random_ether_addr() for tap MAC address. * * Harald Roelle 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 * 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 " #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* 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; } /* 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 = alloc_skb(len + align, GFP_KERNEL))) { tun->dev->stats.rx_dropped++; return -ENOMEM; } if (align) skb_reserve(skb, align); if (memcpy_fromiovec(skb_put(skb, len), 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; 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);