cpu: native: add tap implementation of dev_eth (ng_nativenet)

boards/native/Makefile.features

@@ -1,3 +1,4 @@
+FEATURES_PROVIDED += ethernet
 FEATURES_PROVIDED += transceiver
 FEATURES_PROVIDED += periph_cpuid
 FEATURES_PROVIDED += config

cpu/native/Makefile

@@ -4,6 +4,9 @@ DIRS += periph
 ifneq (,$(filter nativenet,$(USEMODULE)))
 	DIRS += net
 endif
+ifneq (,$(filter ng_nativenet,$(USEMODULE)))
+	DIRS += ng_net
+endif
 
 include $(RIOTBASE)/Makefile.base
 

cpu/native/include/dev_eth_tap.h

@@ -0,0 +1,60 @@
+/*
+ * Copyright (C) 2015 Kaspar Schleiser <kaspar@schleiser.de>
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser General
+ * Public License v2.1. See the file LICENSE in the top level directory for
+ * more details.
+ */
+
+/**
+ * @defgroup    net_dev_eth_impl Low-level Ethernet driver implementations
+ * @ingroup     net_dev_eth_ll
+ * @brief       Low-level ethernet driver for native tap interfaces
+ * @{
+ *
+ * @file
+ * @brief       Definitions for low-level ethernet driver for native tap interfaces
+ *
+ * @author      Kaspar Schleiser <kaspar@schleiser.de>
+ */
+#ifndef DEV_ETH_TAP_H
+#define DEV_ETH_TAP_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+#include "net/dev_eth.h"
+
+#include "net/if.h"
+
+/**
+ * @brief tap interface state
+ */
+typedef struct dev_eth_tap {
+    dev_eth_t ethdev;                   /**< dev_eth internal member */
+    char tap_name[IFNAMSIZ];            /**< host dev file name */
+    int tap_fd;                         /**< host file descriptor for the TAP */
+    uint8_t addr[NG_ETHERNET_ADDR_LEN]; /**< The MAC address of the TAP */
+    uint8_t promiscous;                 /**< Flag for promiscous mode */
+} dev_eth_tap_t;
+
+/**
+ * @brief global device struct. driver only supports one tap device as of now.
+ */
+extern dev_eth_tap_t dev_eth_tap;
+
+/**
+ * @brief Setup dev_eth_tap_t structure.
+ *
+ * @param dev  the preallocated dev_eth_tap device handle to setup
+ * @param name Name of the host system's tap inteface to bind to.
+ */
+void dev_eth_tap_setup(dev_eth_tap_t *dev, const char *name);
+
+#ifdef __cplusplus
+}
+#endif
+/** @} */
+#endif /* DEV_ETH_TAP_H */

cpu/native/ng_net/Makefile

@@ -0,0 +1,5 @@
+MODULE = ng_nativenet
+
+include $(RIOTBASE)/Makefile.base
+
+INCLUDES = $(NATIVEINCLUDES)

cpu/native/ng_net/dev_eth_tap.c

@@ -0,0 +1,296 @@
+/*
+ * Copyright (C) 2015 Ludwig Ortmann <ludwig.ortmann@fu-berlin.de>,
+ *                    Martine Lenders <mlenders@inf.fu-berlin.de>
+ *                    Kaspar Schleiser <kaspar@schleiser.de>
+ *                    Ell-i open source co-operative
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser General
+ * Public License v2.1. See the file LICENSE in the top level directory for
+ * more details.
+ */
+
+/*
+ * @ingroup net_dev_eth
+ * @{
+ * @brief   Low-level ethernet driver for tap interfaces
+ * @author  Kaspar Schleiser <kaspar@schleiser.de>
+ * @}
+ */
+#include <err.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+
+#ifdef __MACH__
+#define _POSIX_C_SOURCE
+#include <net/if.h>
+#undef _POSIX_C_SOURCE
+#include <ifaddrs.h>
+#include <net/if_dl.h>
+#elif defined(__FreeBSD__)
+#include <sys/socket.h>
+#include <net/if.h>
+#include <ifaddrs.h>
+#include <net/if_dl.h>
+#else
+#include <net/if.h>
+#include <linux/if_tun.h>
+#include <linux/if_ether.h>
+#endif
+
+#include "native_internal.h"
+
+#include "net/dev_eth.h"
+#include "dev_eth_tap.h"
+
+#define ENABLE_DEBUG 0
+#include "debug.h"
+
+/* support one tap interface for now */
+dev_eth_tap_t dev_eth_tap;
+
+/* dev_eth interface */
+static int _init(dev_eth_t *ethdev);
+static int _send(dev_eth_t *ethdev, char* buf, int n);
+static int _recv(dev_eth_t *ethdev, char* buf, int n);
+
+static inline void _get_mac_addr(dev_eth_t *ethdev, uint8_t *dst) {
+    dev_eth_tap_t *dev = (dev_eth_tap_t*)ethdev;
+    memcpy(dst, dev->addr, NG_ETHERNET_ADDR_LEN);
+}
+
+static inline int _get_promiscous(dev_eth_t *ethdev) {
+    dev_eth_tap_t *dev = (dev_eth_tap_t*)ethdev;
+    return dev->promiscous;
+}
+
+static inline int _set_promiscous(dev_eth_t *ethdev, int value) {
+    dev_eth_tap_t *dev = (dev_eth_tap_t*)ethdev;
+    dev->promiscous = value;
+    return value;
+}
+
+static inline void _isr(dev_eth_t *ethdev) {
+    dev_eth_rx_handler(ethdev);
+}
+
+static eth_driver_t eth_driver_tap = {
+    .init = _init,
+    .send = _send,
+    .recv = _recv,
+    .get_mac_addr = _get_mac_addr,
+    .get_promiscous = _get_promiscous,
+    .set_promiscous = _set_promiscous,
+    .isr = _isr,
+};
+
+/* driver implementation */
+static inline bool _is_addr_broadcast(uint8_t *addr)
+{
+    return ((addr[0] == 0xff) && (addr[1] == 0xff) && (addr[2] == 0xff) &&
+            (addr[3] == 0xff) && (addr[4] == 0xff) && (addr[5] == 0xff));
+}
+
+static inline bool _is_addr_multicast(uint8_t *addr)
+{
+    /* source: http://ieee802.org/secmail/pdfocSP2xXA6d.pdf */
+    return (addr[0] & 0x01);
+}
+
+static int _recv(dev_eth_t *dev_eth, char *buf, int len) {
+    dev_eth_tap_t *dev = (dev_eth_tap_t*)dev_eth;
+
+    int nread = real_read(dev->tap_fd, buf, len);
+    DEBUG("ng_tapnet: read %d bytes\n", nread);
+
+    if (nread > 0) {
+        ng_ethernet_hdr_t *hdr = (ng_ethernet_hdr_t *)buf;
+        if (!(dev->promiscous) && !_is_addr_multicast(hdr->dst) &&
+            !_is_addr_broadcast(hdr->dst) &&
+            (memcmp(hdr->dst, dev->addr, NG_ETHERNET_ADDR_LEN) != 0)) {
+            DEBUG("ng_eth_dev: received for %02x:%02x:%02x:%02x:%02x:%02x\n"
+                  "That's not me => Dropped\n",
+                  hdr->dst[0], hdr->dst[1], hdr->dst[2],
+                  hdr->dst[3], hdr->dst[4], hdr->dst[5]);
+            return 0;
+        }
+        /* work around lost signals */
+        fd_set rfds;
+        struct timeval t;
+        memset(&t, 0, sizeof(t));
+        FD_ZERO(&rfds);
+        FD_SET(dev->tap_fd, &rfds);
+
+        _native_in_syscall++; /* no switching here */
+
+        if (real_select(dev->tap_fd + 1, &rfds, NULL, NULL, &t) == 1) {
+            int sig = SIGIO;
+            extern int _sig_pipefd[2];
+            extern ssize_t (*real_write)(int fd, const void * buf, size_t count);
+            real_write(_sig_pipefd[1], &sig, sizeof(int));
+            _native_sigpend++;
+            DEBUG("dev_eth_tap: sigpend++\n");
+        }
+        else {
+#ifdef __MACH__
+            kill(_sigio_child_pid, SIGCONT);
+#endif
+        }
+
+        _native_in_syscall--;
+
+        return nread;
+    }
+    else if (nread == -1) {
+        if ((errno == EAGAIN) || (errno == EWOULDBLOCK)) {
+        }
+        else {
+            err(EXIT_FAILURE, "dev_eth_tap: read");
+        }
+    }
+    else if (nread == 0) {
+        DEBUG("_native_handle_tap_input: ignoring null-event");
+    }
+    else {
+        errx(EXIT_FAILURE, "internal error _rx_event");
+    }
+
+    return -1;
+}
+
+static int _send(dev_eth_t *ethdev, char* buf, int n) {
+    dev_eth_tap_t *dev = (dev_eth_tap_t*)ethdev;
+    return _native_write(dev->tap_fd, buf, n);
+}
+
+void dev_eth_tap_setup(dev_eth_tap_t *dev, const char *name) {
+    dev->ethdev.driver = &eth_driver_tap;
+    strncpy(dev->tap_name, name, IFNAMSIZ);
+}
+
+static void _tap_isr(void) {
+    dev_eth_isr(((dev_eth_t *) &dev_eth_tap));
+}
+
+static int _init(dev_eth_t *ethdev)
+{
+    dev_eth_tap_t *dev = (dev_eth_tap_t*)ethdev;
+
+    /* check device parametrs */
+    if (dev == NULL) {
+        return -ENODEV;
+    }
+
+    char *name = dev->tap_name;
+#ifdef __MACH__ /* OSX */
+    char clonedev[255] = "/dev/"; /* XXX bad size */
+    strncpy(clonedev + 5, name, 250);
+#elif defined(__FreeBSD__)
+    char clonedev[255] = "/dev/"; /* XXX bad size */
+    strncpy(clonedev + 5, name, 250);
+#else /* Linux */
+    struct ifreq ifr;
+    const char *clonedev = "/dev/net/tun";
+#endif
+    /* initialize device descriptor */
+    dev->promiscous = 0;
+    /* implicitly create the tap interface */
+    if ((dev->tap_fd = real_open(clonedev , O_RDWR)) == -1) {
+        err(EXIT_FAILURE, "open(%s)", clonedev);
+    }
+#if (defined(__MACH__) || defined(__FreeBSD__)) /* OSX/FreeBSD */
+    struct ifaddrs *iflist;
+    if (real_getifaddrs(&iflist) == 0) {
+        for (struct ifaddrs *cur = iflist; cur; cur = cur->ifa_next) {
+            if ((cur->ifa_addr->sa_family == AF_LINK) && (strcmp(cur->ifa_name, name) == 0) && cur->ifa_addr) {
+                struct sockaddr_dl *sdl = (struct sockaddr_dl *)cur->ifa_addr;
+                memcpy(dev->addr, LLADDR(sdl), sdl->sdl_alen);
+                break;
+            }
+        }
+        real_freeifaddrs(iflist);
+    }
+#else /* Linux */
+    memset(&ifr, 0, sizeof(ifr));
+    ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
+    strncpy(ifr.ifr_name, name, IFNAMSIZ);
+    if (real_ioctl(dev->tap_fd, TUNSETIFF, (void *)&ifr) == -1) {
+        _native_in_syscall++;
+        warn("ioctl TUNSETIFF");
+        warnx("probably the tap interface (%s) does not exist or is already in use", name);
+        real_exit(EXIT_FAILURE);
+    }
+
+    /* get MAC address */
+    memset(&ifr, 0, sizeof(ifr));
+    snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s", name);
+    if (real_ioctl(dev->tap_fd, SIOCGIFHWADDR, &ifr) == -1) {
+        _native_in_syscall++;
+        warn("ioctl SIOCGIFHWADDR");
+        if (real_close(dev->tap_fd) == -1) {
+            warn("close");
+        }
+        real_exit(EXIT_FAILURE);
+    }
+    memcpy(dev->addr, ifr.ifr_hwaddr.sa_data, NG_ETHERNET_ADDR_LEN);
+
+    /* change mac addr so it differs from what the host is using */
+    dev->addr[5]++;
+#endif
+    DEBUG("ng_tapnet_init(): dev->addr = %02x:%02x:%02x:%02x:%02x:%02x\n",
+            dev->addr[0], dev->addr[1], dev->addr[2],
+            dev->addr[3], dev->addr[4], dev->addr[5]);
+    /* configure signal handler for fds */
+    register_interrupt(SIGIO, _tap_isr);
+#ifdef __MACH__
+    /* tuntap signalled IO is not working in OSX,
+     * * check http://sourceforge.net/p/tuntaposx/bugs/17/ */
+    _sigio_child(dev);
+#else
+    /* configure fds to send signals on io */
+    if (fcntl(dev->tap_fd, F_SETOWN, _native_pid) == -1) {
+        err(EXIT_FAILURE, "ng_tapnet_init(): fcntl(F_SETOWN)");
+    }
+    /* set file access mode to non-blocking */
+    if (fcntl(dev->tap_fd, F_SETFL, O_NONBLOCK | O_ASYNC) == -1) {
+        err(EXIT_FAILURE, "ng_tabnet_init(): fcntl(F_SETFL)");
+    }
+#endif /* not OSX */
+    DEBUG("ng_tapnet: initialized.\n");
+    return 0;
+}
+
+#ifdef __MACH__
+static void _sigio_child(ng_tapnet_t *dev)
+{
+    pid_t parent = _native_pid;
+    if ((_sigio_child_pid = real_fork()) == -1) {
+        err(EXIT_FAILURE, "sigio_child: fork");
+    }
+    if (_sigio_child_pid > 0) {
+        /* return in parent process */
+        return;
+    }
+    /* watch tap interface and signal parent process if data is
+     * available */
+    fd_set rfds;
+    while (1) {
+        FD_ZERO(&rfds);
+        FD_SET(dev->tap_fd, &rfds);
+        if (real_select(dev->tap_fd + 1, &rfds, NULL, NULL, NULL) == 1) {
+            kill(parent, SIGIO);
+        }
+        else {
+            kill(parent, SIGKILL);
+            err(EXIT_FAILURE, "osx_sigio_child: select");
+        }
+        pause();
+    }
+}
+#endif

cpu/native/startup.c

@@ -47,6 +47,11 @@ unsigned _native_rng_seed = 0;
 int _native_rng_mode = 0;
 const char *_native_unix_socket_path = NULL;
 
+#ifdef MODULE_NG_NATIVENET
+#include "dev_eth_tap.h"
+extern dev_eth_tap_t dev_eth_tap;
+#endif
+
 /**
  * initialize _native_null_in_pipe to allow for reading from stdin
  * @param stdiotype: "stdio" (only initialize pipe) or any string
@@ -192,7 +197,7 @@ void usage_exit(void)
 {
     real_printf("usage: %s", _progname);
 
-#ifdef MODULE_NATIVENET
+#if defined(MODULE_NATIVENET) || defined(MODULE_NG_NATIVENET)
     real_printf(" <tap interface>");
 #endif
 
@@ -252,7 +257,7 @@ __attribute__((constructor)) static void startup(int argc, char **argv)
     int replay = 0;
 #endif
 
-#ifdef MODULE_NATIVENET
+#if defined(MODULE_NATIVENET) || defined(MODULE_NG_NATIVENET)
     if (
             (argc < 2)
             || (
@@ -367,6 +372,12 @@ __attribute__((constructor)) static void startup(int argc, char **argv)
 #ifdef MODULE_NATIVENET
     tap_init(argv[1]);
 #endif
+#ifdef MODULE_NG_NATIVENET
+# ifdef MODULE_NATIVENET
+#  error  "Modules nativenet and ng_native are mutually exclusive."
+# endif
+    dev_eth_tap_setup(&dev_eth_tap, argv[1]);
+#endif
 
     board_init();