/**************************************************************************** * drivers/net/tun.c * * Copyright (C) 2015-2016 Max Nekludov. All rights reserved. * Author: Max Nekludov * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include #ifndef CONFIG_DISABLE_POLL # include #endif #include #include #ifdef CONFIG_NET_PKT # include #endif #include #include #include #include #include #include #include #include #if defined(CONFIG_NET) && defined(CONFIG_NET_TUN) /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* If processing is not done at the interrupt level, then high priority * work queue support is required. */ #if !defined(CONFIG_SCHED_WORKQUEUE) # error Work queue support is required in this configuration (CONFIG_SCHED_WORKQUEUE) #else # if defined(CONFIG_TUN_HPWORK) # define TUNWORK HPWORK # elif defined(CONFIG_TUN_LPWORK) # define TUNWORK LPWORK # else # error "Neither CONFIG_TUN_HPWORK nor CONFIG_TUN_LPWORK defined" # endif #endif /* CONFIG_TUN_NINTERFACES determines the number of physical interfaces * that will be supported. */ #ifndef CONFIG_TUN_NINTERFACES # define CONFIG_TUN_NINTERFACES 1 #endif /* TX poll delay = 1 seconds. CLK_TCK is the number of clock ticks per * second */ #define TUN_WDDELAY (1*CLK_TCK) /**************************************************************************** * Private Types ****************************************************************************/ /* The tun_device_s encapsulates all state information for a single hardware * interface */ struct tun_device_s { bool bifup; /* true:ifup false:ifdown */ WDOG_ID txpoll; /* TX poll timer */ struct work_s work; /* For deferring poll work to the work queue */ FAR struct file *filep; #ifndef CONFIG_DISABLE_POLL FAR struct pollfd *poll_fds; #endif bool read_wait; uint8_t read_buf[CONFIG_NET_TUN_MTU]; size_t read_d_len; uint8_t write_buf[CONFIG_NET_TUN_MTU]; size_t write_d_len; sem_t waitsem; sem_t read_wait_sem; /* This holds the information visible to the NuttX network */ struct net_driver_s dev; /* Interface understood by the network */ }; struct tun_driver_s { uint8_t free_tuns; sem_t waitsem; }; /**************************************************************************** * Private Function Prototypes ****************************************************************************/ static void tun_lock(FAR struct tun_device_s *priv); static void tun_unlock(FAR struct tun_device_s *priv); /* Common TX logic */ static int tun_fd_transmit(FAR struct tun_device_s *priv); static int tun_txpoll(struct net_driver_s *dev); /* Interrupt handling */ static void tun_net_receive(FAR struct tun_device_s *priv); static void tun_txdone(FAR struct tun_device_s *priv); /* Watchdog timer expirations */ static void tun_poll_work(FAR void *arg); static void tun_poll_expiry(int argc, wdparm_t arg, ...); /* NuttX callback functions */ static int tun_ifup(FAR struct net_driver_s *dev); static int tun_ifdown(FAR struct net_driver_s *dev); static int tun_txavail(FAR struct net_driver_s *dev); #ifdef CONFIG_NET_IGMP static int tun_addmac(FAR struct net_driver_s *dev, FAR const uint8_t *mac); static int tun_rmmac(FAR struct net_driver_s *dev, FAR const uint8_t *mac); #endif #ifdef CONFIG_NET_ICMPv6 static void tun_ipv6multicast(FAR struct tun_device_s *priv); #endif static int tun_dev_init(FAR struct tun_device_s *priv, FAR struct file *filep, FAR const char *devfmt); static int tun_dev_uninit(FAR struct tun_device_s *priv); /* File interface */ static int tun_open(FAR struct file *filep); static int tun_close(FAR struct file *filep); static ssize_t tun_read(FAR struct file *filep, FAR char *buffer, size_t buflen); static ssize_t tun_write(FAR struct file *filep, FAR const char *buffer, size_t buflen); static int tun_ioctl(FAR struct file *filep, int cmd, unsigned long arg); #ifndef CONFIG_DISABLE_POLL static int tun_poll(FAR struct file *filep, FAR struct pollfd *fds, bool setup); #endif /**************************************************************************** * Private Data ****************************************************************************/ static struct tun_driver_s g_tun; static struct tun_device_s g_tun_devices[CONFIG_TUN_NINTERFACES]; static const struct file_operations g_tun_file_ops = { tun_open, /* open */ tun_close, /* close */ tun_read, /* read */ tun_write, /* write */ 0, /* seek */ tun_ioctl, /* ioctl */ #ifndef CONFIG_DISABLE_POLL tun_poll, /* poll */ #endif }; /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: tundev_lock ****************************************************************************/ static void tundev_lock(FAR struct tun_driver_s *tun) { /* Take the semaphore (perhaps waiting) */ while (sem_wait(&tun->waitsem) != 0) { /* The only case that an error should occur here is if * the wait was awakened by a signal. */ ASSERT(errno == EINTR); } } /**************************************************************************** * Name: tundev_unlock ****************************************************************************/ static void tundev_unlock(FAR struct tun_driver_s *tun) { sem_post(&tun->waitsem); } /**************************************************************************** * Name: tun_lock ****************************************************************************/ static void tun_lock(FAR struct tun_device_s *priv) { /* Take the semaphore (perhaps waiting) */ while (sem_wait(&priv->waitsem) != 0) { /* The only case that an error should occur here is if * the wait was awakened by a signal. */ ASSERT(errno == EINTR); } } /**************************************************************************** * Name: tun_unlock ****************************************************************************/ static void tun_unlock(FAR struct tun_device_s *priv) { sem_post(&priv->waitsem); } /**************************************************************************** * Name: tun_pollnotify ****************************************************************************/ #ifndef CONFIG_DISABLE_POLL static void tun_pollnotify(FAR struct tun_device_s *priv, pollevent_t eventset) { FAR struct pollfd *fds = priv->poll_fds; if (fds == NULL) { return; } eventset &= fds->events; if (eventset != 0) { fds->revents |= eventset; sem_post(fds->sem); } } #else # define tun_pollnotify(dev, event) #endif /**************************************************************************** * Name: tun_transmit * * Description: * Start hardware transmission. Called either from the txdone interrupt * handling or from watchdog based polling. * * Parameters: * priv - Reference to the driver state structure * * Returned Value: * OK on success; a negated errno on failure * * Assumptions: * May or may not be called from an interrupt handler. In either case, * global interrupts are disabled, either explicitly or indirectly through * interrupt handling logic. * ****************************************************************************/ static int tun_fd_transmit(FAR struct tun_device_s *priv) { NETDEV_TXPACKETS(&priv->dev); /* Verify that the hardware is ready to send another packet. If we get * here, then we are committed to sending a packet; Higher level logic * must have assured that there is no transmission in progress. */ if (priv->read_wait) { priv->read_wait = false; sem_post(&priv->read_wait_sem); } tun_pollnotify(priv, POLLIN); return OK; } /**************************************************************************** * Name: tun_txpoll * * Description: * The transmitter is available, check if the network has any outgoing packets * ready to send. This is a callback from devif_poll(). devif_poll() may * be called: * * 1. When the preceding TX packet send is complete, * 2. When the preceding TX packet send timesout and the interface is reset * 3. During normal TX polling * * Parameters: * dev - Reference to the NuttX driver state structure * * Returned Value: * OK on success; a negated errno on failure * * Assumptions: * May or may not be called from an interrupt handler. In either case, * global interrupts are disabled, either explicitly or indirectly through * interrupt handling logic. * ****************************************************************************/ static int tun_txpoll(struct net_driver_s *dev) { FAR struct tun_device_s *priv = (FAR struct tun_device_s *)dev->d_private; /* If the polling resulted in data that should be sent out on the network, * the field d_len is set to a value > 0. */ if (priv->dev.d_len > 0) { /* Send the packet */ priv->read_d_len = priv->dev.d_len; tun_fd_transmit(priv); return 1; } /* If zero is returned, the polling will continue until all connections have * been examined. */ return 0; } /**************************************************************************** * Name: tun_receive * * Description: * An interrupt was received indicating the availability of a new RX packet * * Parameters: * priv - Reference to the driver state structure * * Returned Value: * None * * Assumptions: * Global interrupts are disabled by interrupt handling logic. * ****************************************************************************/ static void tun_net_receive(FAR struct tun_device_s *priv) { int ret; /* Copy the data data from the hardware to priv->dev.d_buf. Set amount of * data in priv->dev.d_len */ NETDEV_RXPACKETS(&priv->dev); #ifdef CONFIG_NET_PKT /* When packet sockets are enabled, feed the frame into the packet tap */ pkt_input(&priv->dev); #endif /* We only accept IP packets of the configured type and ARP packets */ #if defined(CONFIG_NET_IPv4) ninfo("IPv4 frame\n"); NETDEV_RXIPV4(&priv->dev); /* Give the IPv4 packet to the network layer. ipv4_input will return * an error if it is unable to dispatch the packet at this time. */ ret = ipv4_input(&priv->dev); if (ret == OK) { /* If the above function invocation resulted in data that should be * sent out on the network, the field d_len will set to a value > 0. */ if (priv->dev.d_len > 0) { priv->write_d_len = priv->dev.d_len; tun_fd_transmit(priv); } else { tun_pollnotify(priv, POLLOUT); } } else { priv->dev.d_len = 0; tun_pollnotify(priv, POLLOUT); } #elif defined(CONFIG_NET_IPv6) ninfo("Iv6 frame\n"); NETDEV_RXIPV6(&priv->dev); /* Give the IPv6 packet to the network layer. ipv6_input will return * an error if it is unable to dispatch the packet at this time. */ ret = ipv6_input(&priv->dev); if (ret == OK) { /* If the above function invocation resulted in data that should be * sent out on the network, the field d_len will set to a value > 0. */ if (priv->dev.d_len > 0) { priv->write_d_len = priv->dev.d_len; tun_fd_transmit(priv); } else { tun_pollnotify(priv, POLLOUT); } } else { priv->write_d_len = 0; tun_pollnotify(priv, POLLOUT); } #else NETDEV_RXDROPPED(&priv->dev); #endif } /**************************************************************************** * Name: tun_txdone * * Description: * An interrupt was received indicating that the last TX packet(s) is done * * Parameters: * dev - Reference to the driver state structure * * Returned Value: * None * * Assumptions: * Global interrupts are disabled by the watchdog logic. * ****************************************************************************/ static void tun_txdone(FAR struct tun_device_s *priv) { /* Check for errors and update statistics */ NETDEV_TXDONE(&priv->dev); /* Then poll the network for new XMIT data */ priv->dev.d_buf = priv->read_buf; (void)devif_poll(&priv->dev, tun_txpoll); } /**************************************************************************** * Name: tun_poll_work * * Description: * Perform periodic polling from the worker thread * * Parameters: * arg - The argument passed when work_queue() as called. * * Returned Value: * OK on success * * Assumptions: * Ethernet interrupts are disabled * ****************************************************************************/ static void tun_poll_work(FAR void *arg) { FAR struct tun_device_s *priv = (FAR struct tun_device_s *)arg; /* Perform the poll */ tun_lock(priv); net_lock(); /* Check if there is room in the send another TX packet. We cannot perform * the TX poll if he are unable to accept another packet for transmission. */ if (priv->read_d_len == 0) { /* If so, poll the network for new XMIT data. */ priv->dev.d_buf = priv->read_buf; (void)devif_timer(&priv->dev, tun_txpoll); } /* Setup the watchdog poll timer again */ (void)wd_start(priv->txpoll, TUN_WDDELAY, tun_poll_expiry, 1, priv); net_unlock(); tun_unlock(priv); } /**************************************************************************** * Name: tun_poll_expiry * * Description: * Periodic timer handler. Called from the timer interrupt handler. * * Parameters: * argc - The number of available arguments * arg - The first argument * * Returned Value: * None * * Assumptions: * Global interrupts are disabled by the watchdog logic. * ****************************************************************************/ static void tun_poll_expiry(int argc, wdparm_t arg, ...) { FAR struct tun_device_s *priv = (FAR struct tun_device_s *)arg; /* Schedule to perform the timer expiration on the worker thread. */ work_queue(TUNWORK, &priv->work, tun_poll_work, priv, 0); } /**************************************************************************** * Name: tun_ifup * * Description: * NuttX Callback: Bring up the Ethernet interface when an IP address is * provided * * Parameters: * dev - Reference to the NuttX driver state structure * * Returned Value: * None * * Assumptions: * ****************************************************************************/ static int tun_ifup(struct net_driver_s *dev) { FAR struct tun_device_s *priv = (FAR struct tun_device_s *)dev->d_private; #ifdef CONFIG_NET_IPv4 ninfo("Bringing up: %d.%d.%d.%d\n", dev->d_ipaddr & 0xff, (dev->d_ipaddr >> 8) & 0xff, (dev->d_ipaddr >> 16) & 0xff, dev->d_ipaddr >> 24); #endif #ifdef CONFIG_NET_IPv6 ninfo("Bringing up: %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n", dev->d_ipv6addr[0], dev->d_ipv6addr[1], dev->d_ipv6addr[2], dev->d_ipv6addr[3], dev->d_ipv6addr[4], dev->d_ipv6addr[5], dev->d_ipv6addr[6], dev->d_ipv6addr[7]); #endif /* Initialize PHYs, the Ethernet interface, and setup up Ethernet interrupts */ /* Instantiate the MAC address from priv->dev.d_mac.ether.ether_addr_octet */ #ifdef CONFIG_NET_ICMPv6 /* Set up IPv6 multicast address filtering */ tun_ipv6multicast(priv); #endif /* Set and activate a timer process */ (void)wd_start(priv->txpoll, TUN_WDDELAY, tun_poll_expiry, 1, (wdparm_t)priv); priv->bifup = true; return OK; } /**************************************************************************** * Name: tun_ifdown * * Description: * NuttX Callback: Stop the interface. * * Parameters: * dev - Reference to the NuttX driver state structure * * Returned Value: * None * * Assumptions: * ****************************************************************************/ static int tun_ifdown(struct net_driver_s *dev) { FAR struct tun_device_s *priv = (FAR struct tun_device_s *)dev->d_private; irqstate_t flags; flags = enter_critical_section(); /* Cancel the TX poll timer */ wd_cancel(priv->txpoll); /* Mark the device "down" */ priv->bifup = false; leave_critical_section(flags); return OK; } /**************************************************************************** * Name: tun_txavail_work * * Description: * Driver callback invoked when new TX data is available. This is a * stimulus perform an out-of-cycle poll and, thereby, reduce the TX * latency. * * Parameters: * dev - Reference to the NuttX driver state structure * * Returned Value: * None * * Assumptions: * Called in normal user mode * ****************************************************************************/ static void tun_txavail_work(FAR void *arg) { FAR struct tun_device_s *priv = (FAR struct tun_device_s *)arg; tun_lock(priv); /* Check if there is room to hold another network packet. */ if (priv->read_d_len != 0 || priv->write_d_len != 0) { tun_unlock(priv); return; } net_lock(); if (priv->bifup) { /* Poll the network for new XMIT data */ priv->dev.d_buf = priv->read_buf; (void)devif_poll(&priv->dev, tun_txpoll); } net_unlock(); tun_unlock(priv); } /**************************************************************************** * Name: tun_txavail * * Description: * Driver callback invoked when new TX data is available. This is a * stimulus perform an out-of-cycle poll and, thereby, reduce the TX * latency. * * Parameters: * dev - Reference to the NuttX driver state structure * * Returned Value: * None * * Assumptions: * Called from the network stack with the network locked. * ****************************************************************************/ static int tun_txavail(struct net_driver_s *dev) { FAR struct tun_device_s *priv = (FAR struct tun_device_s *)dev->d_private; /* Schedule to perform the TX poll on the worker thread. */ if (work_available(&priv->work)) { work_queue(TUNWORK, &priv->work, tun_txavail_work, priv, 0); } return OK; } /**************************************************************************** * Name: tun_addmac * * Description: * NuttX Callback: Add the specified MAC address to the hardware multicast * address filtering * * Parameters: * dev - Reference to the NuttX driver state structure * mac - The MAC address to be added * * Returned Value: * None * * Assumptions: * ****************************************************************************/ #ifdef CONFIG_NET_IGMP static int tun_addmac(struct net_driver_s *dev, FAR const uint8_t *mac) { /* Add the MAC address to the hardware multicast routing table */ return OK; } #endif /**************************************************************************** * Name: tun_rmmac * * Description: * NuttX Callback: Remove the specified MAC address from the hardware multicast * address filtering * * Parameters: * dev - Reference to the NuttX driver state structure * mac - The MAC address to be removed * * Returned Value: * None * * Assumptions: * ****************************************************************************/ #ifdef CONFIG_NET_IGMP static int tun_rmmac(struct net_driver_s *dev, FAR const uint8_t *mac) { /* Add the MAC address to the hardware multicast routing table */ return OK; } #endif /**************************************************************************** * Name: tun_ipv6multicast * * Description: * Configure the IPv6 multicast MAC address. * * Parameters: * priv - A reference to the private driver state structure * * Returned Value: * OK on success; Negated errno on failure. * * Assumptions: * ****************************************************************************/ #ifdef CONFIG_NET_ICMPv6 static void tun_ipv6multicast(FAR struct tun_device_s *priv) { } #endif /* CONFIG_NET_ICMPv6 */ /**************************************************************************** * Name: tun_dev_init * * Description: * Initialize the TUN device * * Parameters: * * Returned Value: * OK on success; Negated errno on failure. * * Assumptions: * ****************************************************************************/ static int tun_dev_init(FAR struct tun_device_s *priv, FAR struct file *filep, FAR const char *devfmt) { int ret; /* Initialize the driver structure */ memset(priv, 0, sizeof(struct tun_device_s)); priv->dev.d_ifup = tun_ifup; /* I/F up (new IP address) callback */ priv->dev.d_ifdown = tun_ifdown; /* I/F down callback */ priv->dev.d_txavail = tun_txavail; /* New TX data callback */ #ifdef CONFIG_NET_IGMP priv->dev.d_addmac = tun_addmac; /* Add multicast MAC address */ priv->dev.d_rmmac = tun_rmmac; /* Remove multicast MAC address */ #endif priv->dev.d_private = (FAR void *)priv; /* Used to recover private state from dev */ /* Initialize the mutual exlcusion and wait semaphore */ sem_init(&priv->waitsem, 0, 1); sem_init(&priv->read_wait_sem, 0, 0); /* The wait semaphore is used for signaling and, hence, should not have * priority inheritance enabled. */ sem_setprotocol(&priv->read_wait_sem, SEM_PRIO_NONE); /* Create a watchdog for timing polling for and timing of transmisstions */ priv->txpoll = wd_create(); /* Create periodic poll timer */ /* Initialize other variables */ priv->write_d_len = 0; priv->read_wait = false; /* Put the interface in the down state */ tun_ifdown(&priv->dev); if (devfmt) { strncpy(priv->dev.d_ifname, devfmt, IFNAMSIZ); } /* Register the device with the OS so that socket IOCTLs can be performed */ ret = netdev_register(&priv->dev, NET_LL_TUN); if (ret != OK) { sem_destroy(&priv->waitsem); sem_destroy(&priv->read_wait_sem); return ret; } priv->filep = filep; /* Set link to file */ filep->f_priv = priv; /* Set link to TUN device */ return ret; } /**************************************************************************** * Name: tun_dev_uninit ****************************************************************************/ static int tun_dev_uninit(FAR struct tun_device_s *priv) { /* Put the interface in the down state */ tun_ifdown(&priv->dev); /* Remove the device from the OS */ (void)netdev_unregister(&priv->dev); sem_destroy(&priv->waitsem); sem_destroy(&priv->read_wait_sem); return OK; } /**************************************************************************** * Name: tun_open ****************************************************************************/ static int tun_open(FAR struct file *filep) { filep->f_priv = 0; return OK; } /**************************************************************************** * Name: tun_close ****************************************************************************/ static int tun_close(FAR struct file *filep) { FAR struct inode *inode = filep->f_inode; FAR struct tun_driver_s *tun = inode->i_private; FAR struct tun_device_s *priv = filep->f_priv; int intf; if (!priv) { return OK; } intf = priv - g_tun_devices; tundev_lock(tun); tun->free_tuns |= (1 << intf); (void)tun_dev_uninit(priv); tundev_unlock(tun); return OK; } /**************************************************************************** * Name: tun_write ****************************************************************************/ static ssize_t tun_write(FAR struct file *filep, FAR const char *buffer, size_t buflen) { FAR struct tun_device_s *priv = filep->f_priv; ssize_t ret; if (!priv) { return -EINVAL; } tun_lock(priv); if (priv->write_d_len > 0) { tun_unlock(priv); return -EBUSY; } net_lock(); if (buflen > CONFIG_NET_TUN_MTU) { ret = -EINVAL; } else { memcpy(priv->write_buf, buffer, buflen); priv->dev.d_buf = priv->write_buf; priv->dev.d_len = buflen; tun_net_receive(priv); ret = (ssize_t)buflen; } net_unlock(); tun_unlock(priv); return ret; } /**************************************************************************** * Name: tun_read ****************************************************************************/ static ssize_t tun_read(FAR struct file *filep, FAR char *buffer, size_t buflen) { FAR struct tun_device_s *priv = filep->f_priv; ssize_t ret; size_t write_d_len; size_t read_d_len; if (!priv) { return -EINVAL; } tun_lock(priv); /* Check if there are data to read in write buffer */ write_d_len = priv->write_d_len; if (write_d_len > 0) { if (buflen < write_d_len) { ret = -EINVAL; goto out; } memcpy(buffer, priv->write_buf, write_d_len); ret = (ssize_t)write_d_len; priv->write_d_len = 0; tun_pollnotify(priv, POLLOUT); if (priv->read_d_len == 0) { net_lock(); tun_txdone(priv); net_unlock(); } goto out; } if (priv->read_d_len == 0) { if ((filep->f_oflags & O_NONBLOCK) != 0) { ret = -EAGAIN; goto out; } priv->read_wait = true; tun_unlock(priv); sem_wait(&priv->read_wait_sem); tun_lock(priv); } net_lock(); read_d_len = priv->read_d_len; if (buflen < read_d_len) { ret = -EINVAL; } else { memcpy(buffer, priv->read_buf, read_d_len); ret = (ssize_t)read_d_len; } priv->read_d_len = 0; tun_txdone(priv); net_unlock(); out: tun_unlock(priv); return ret; } /**************************************************************************** * Name: tun_poll ****************************************************************************/ #ifndef CONFIG_DISABLE_POLL int tun_poll(FAR struct file *filep, FAR struct pollfd *fds, bool setup) { FAR struct tun_device_s *priv = filep->f_priv; pollevent_t eventset; int ret = OK; if (!priv) { return -EINVAL; } /* Some sanity checking */ if (!priv || !fds) { return -ENODEV; } tun_lock(priv); if (setup) { if (priv->poll_fds) { ret = -EBUSY; goto errout; } priv->poll_fds = fds; eventset = 0; /* If write buffer is empty notify App. */ if (priv->write_d_len == 0) { eventset |= (fds->events & POLLOUT); } /* The write buffer sometimes could be used for TX. * So check it too. */ if (priv->read_d_len != 0 || priv->write_d_len != 0) { eventset |= (fds->events & POLLIN); } if (eventset) { tun_pollnotify(priv, eventset); } } else { priv->poll_fds = 0; } errout: tun_unlock(priv); return ret; } #endif /**************************************************************************** * Name: tun_ioctl ****************************************************************************/ static int tun_ioctl(FAR struct file *filep, int cmd, unsigned long arg) { FAR struct inode *inode = filep->f_inode; FAR struct tun_driver_s *tun = inode->i_private; FAR struct tun_device_s *priv = filep->f_priv; int ret = OK; if (cmd == TUNSETIFF && priv == NULL) { uint8_t free_tuns; int intf; FAR struct ifreq *ifr = (FAR struct ifreq *)arg; if (!ifr || ((ifr->ifr_flags & IFF_MASK) != IFF_TUN && (ifr->ifr_flags & IFF_MASK) != IFF_TAP)) { return -EINVAL; } tundev_lock(tun); free_tuns = tun->free_tuns; if (free_tuns == 0) { tundev_unlock(tun); return -ENOMEM; } for (intf = 0; intf < CONFIG_TUN_NINTERFACES && !(free_tuns & 1); intf++, free_tuns >>= 1); ret = tun_dev_init(&g_tun_devices[intf], filep, *ifr->ifr_name ? ifr->ifr_name : 0); if (ret != OK) { tundev_unlock(tun); return ret; } tun->free_tuns &= ~(1 << intf); priv = filep->f_priv; strncpy(ifr->ifr_name, priv->dev.d_ifname, IFNAMSIZ); if ((ifr->ifr_flags & IFF_MASK) == IFF_TAP) { /* TAP device -> handling raw Ethernet packets * -> set appropriate Ethernet header length */ priv->dev.d_llhdrlen = ETH_HDRLEN; } else if ((ifr->ifr_flags & IFF_MASK) == IFF_TUN) { /* TUN device -> handling an application data stream * -> no header */ priv->dev.d_llhdrlen = 0; } tundev_unlock(tun); return OK; } return -EBADFD; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: tun_initialize * * Description: * Instantiate a SLIP network interface. * * Parameters: * * Returned Value: * OK on success; Negated errno on failure. * * Assumptions: * ****************************************************************************/ int tun_initialize(void) { sem_init(&g_tun.waitsem, 0, 1); g_tun.free_tuns = (1 << CONFIG_TUN_NINTERFACES) - 1; (void)register_driver("/dev/tun", &g_tun_file_ops, 0644, &g_tun); return OK; } #endif /* CONFIG_NET && CONFIG_NET_TUN */