Const correctness.
[tinc] / src / linux / device.c
index 35c66d5..38debe8 100644 (file)
@@ -1,7 +1,7 @@
 /*
     device.c -- Interaction with Linux ethertap and tun/tap device
     Copyright (C) 2001-2005 Ivo Timmermans,
-                  2001-2009 Guus Sliepen <guus@tinc-vpn.org>
+                  2001-2014 Guus Sliepen <guus@tinc-vpn.org>
 
     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
@@ -18,7 +18,7 @@
     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
 
-#include "system.h"
+#include "../system.h"
 
 #ifdef HAVE_LINUX_IF_TUN_H
 #include <linux/if_tun.h>
 #define DEFAULT_DEVICE "/dev/tap0"
 #endif
 
-#include "conf.h"
-#include "logger.h"
-#include "net.h"
-#include "route.h"
-#include "utils.h"
-#include "xalloc.h"
+#include "../conf.h"
+#include "../device.h"
+#include "../logger.h"
+#include "../net.h"
+#include "../route.h"
+#include "../utils.h"
+#include "../xalloc.h"
 
 typedef enum device_type_t {
        DEVICE_TYPE_ETHERTAP,
@@ -44,24 +45,29 @@ int device_fd = -1;
 static device_type_t device_type;
 char *device = NULL;
 char *iface = NULL;
+static char *type = NULL;
 static char ifrname[IFNAMSIZ];
-static char *device_info;
+static const char *device_info;
 
-static int device_total_in = 0;
-static int device_total_out = 0;
+static uint64_t device_total_in = 0;
+static uint64_t device_total_out = 0;
 
-bool setup_device(void) {
+static bool setup_device(void) {
        struct ifreq ifr;
+       bool t1q = false;
 
-       if(!get_config_string(lookup_config(config_tree, "Device"), &device))
+       if(!get_config_string(lookup_config(config_tree, "Device"), &device)) {
                device = xstrdup(DEFAULT_DEVICE);
+       }
 
        if(!get_config_string(lookup_config(config_tree, "Interface"), &iface))
 #ifdef HAVE_LINUX_IF_TUN_H
-               if (netname != NULL)
+               if(netname != NULL) {
                        iface = xstrdup(netname);
+               }
+
 #else
-               iface = xstrdup(rindex(device, '/') ? rindex(device, '/') + 1 : device);
+               iface = xstrdup(strrchr(device, '/') ? strrchr(device, '/') + 1 : device);
 #endif
        device_fd = open(device, O_RDWR | O_NONBLOCK);
 
@@ -70,42 +76,79 @@ bool setup_device(void) {
                return false;
        }
 
+#ifdef FD_CLOEXEC
+       fcntl(device_fd, F_SETFD, FD_CLOEXEC);
+#endif
+
 #ifdef HAVE_LINUX_IF_TUN_H
        /* Ok now check if this is an old ethertap or a new tun/tap thingie */
 
        memset(&ifr, 0, sizeof(ifr));
-       if(routing_mode == RMODE_ROUTER) {
+
+       get_config_string(lookup_config(config_tree, "DeviceType"), &type);
+
+       if(type && strcasecmp(type, "tun") && strcasecmp(type, "tap")) {
+               logger(LOG_ERR, "Unknown device type %s!", type);
+               return false;
+       }
+
+       if((type && !strcasecmp(type, "tun")) || (!type && routing_mode == RMODE_ROUTER)) {
                ifr.ifr_flags = IFF_TUN;
                device_type = DEVICE_TYPE_TUN;
                device_info = "Linux tun/tap device (tun mode)";
        } else {
+               if(routing_mode == RMODE_ROUTER) {
+                       overwrite_mac = true;
+               }
+
                ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
                device_type = DEVICE_TYPE_TAP;
                device_info = "Linux tun/tap device (tap mode)";
        }
 
-       if(iface)
+#ifdef IFF_ONE_QUEUE
+
+       /* Set IFF_ONE_QUEUE flag... */
+       if(get_config_bool(lookup_config(config_tree, "IffOneQueue"), &t1q) && t1q) {
+               ifr.ifr_flags |= IFF_ONE_QUEUE;
+       }
+
+#endif
+
+       if(iface) {
                strncpy(ifr.ifr_name, iface, IFNAMSIZ);
+               ifr.ifr_name[IFNAMSIZ - 1] = 0;
+       }
 
        if(!ioctl(device_fd, TUNSETIFF, &ifr)) {
                strncpy(ifrname, ifr.ifr_name, IFNAMSIZ);
-               if(iface) free(iface);
+               ifrname[IFNAMSIZ - 1] = 0;
+               free(iface);
                iface = xstrdup(ifrname);
+       } else if(errno == EPERM || errno == EBUSY) {
+               logger(LOG_ERR, "Error while trying to configure %s: %s", device, strerror(errno));
+               return false;
        } else if(!ioctl(device_fd, (('T' << 8) | 202), &ifr)) {
                logger(LOG_WARNING, "Old ioctl() request was needed for %s", device);
                strncpy(ifrname, ifr.ifr_name, IFNAMSIZ);
-               if(iface) free(iface);
+               ifrname[IFNAMSIZ - 1] = 0;
+               free(iface);
                iface = xstrdup(ifrname);
        } else
 #endif
        {
-               if(routing_mode == RMODE_ROUTER)
+               if(routing_mode == RMODE_ROUTER) {
                        overwrite_mac = true;
+               }
+
                device_info = "Linux ethertap device";
                device_type = DEVICE_TYPE_ETHERTAP;
-               if(iface)
-                       free(iface);
-               iface = xstrdup(rindex(device, '/') ? rindex(device, '/') + 1 : device);
+               free(iface);
+               iface = xstrdup(strrchr(device, '/') ? strrchr(device, '/') + 1 : device);
+       }
+
+       if(overwrite_mac && !ioctl(device_fd, SIOCGIFHWADDR, &ifr)) {
+               memcpy(mymac.x, ifr.ifr_hwaddr.sa_data, ETH_ALEN);
        }
 
        logger(LOG_INFO, "%s is a %s", device, device_info);
@@ -113,89 +156,99 @@ bool setup_device(void) {
        return true;
 }
 
-void close_device(void) {
+static void close_device(void) {
        close(device_fd);
 
+       free(type);
        free(device);
        free(iface);
 }
 
-bool read_packet(vpn_packet_t *packet) {
+static bool read_packet(vpn_packet_t *packet) {
        int lenin;
-       
+
        switch(device_type) {
-               case DEVICE_TYPE_TUN:
-                       lenin = read(device_fd, packet->data + 10, MTU - 10);
-
-                       if(lenin <= 0) {
-                               logger(LOG_ERR, "Error while reading from %s %s: %s",
-                                          device_info, device, strerror(errno));
-                               return false;
-                       }
-
-                       packet->len = lenin + 10;
-                       break;
-               case DEVICE_TYPE_TAP:
-                       lenin = read(device_fd, packet->data, MTU);
-
-                       if(lenin <= 0) {
-                               logger(LOG_ERR, "Error while reading from %s %s: %s",
-                                          device_info, device, strerror(errno));
-                               return false;
-                       }
-
-                       packet->len = lenin;
-                       break;
-               case DEVICE_TYPE_ETHERTAP:
-                       lenin = read(device_fd, packet->data - 2, MTU + 2);
-
-                       if(lenin <= 0) {
-                               logger(LOG_ERR, "Error while reading from %s %s: %s",
-                                          device_info, device, strerror(errno));
-                               return false;
-                       }
-
-                       packet->len = lenin - 2;
-                       break;
+       case DEVICE_TYPE_TUN:
+               lenin = read(device_fd, packet->data + 10, MTU - 10);
+
+               if(lenin <= 0) {
+                       logger(LOG_ERR, "Error while reading from %s %s: %s",
+                              device_info, device, strerror(errno));
+                       return false;
+               }
+
+               memset(packet->data, 0, 12);
+               packet->len = lenin + 10;
+               break;
+
+       case DEVICE_TYPE_TAP:
+               lenin = read(device_fd, packet->data, MTU);
+
+               if(lenin <= 0) {
+                       logger(LOG_ERR, "Error while reading from %s %s: %s",
+                              device_info, device, strerror(errno));
+                       return false;
+               }
+
+               packet->len = lenin;
+               break;
+
+       case DEVICE_TYPE_ETHERTAP:
+               lenin = read(device_fd, packet->data - 2, MTU + 2);
+
+               if(lenin <= 0) {
+                       logger(LOG_ERR, "Error while reading from %s %s: %s",
+                              device_info, device, strerror(errno));
+                       return false;
+               }
+
+               packet->len = lenin - 2;
+               break;
        }
 
        device_total_in += packet->len;
 
        ifdebug(TRAFFIC) logger(LOG_DEBUG, "Read packet of %d bytes from %s", packet->len,
-                          device_info);
+                               device_info);
 
        return true;
 }
 
-bool write_packet(vpn_packet_t *packet) {
+static bool write_packet(vpn_packet_t *packet) {
        ifdebug(TRAFFIC) logger(LOG_DEBUG, "Writing packet of %d bytes to %s",
-                          packet->len, device_info);
+                               packet->len, device_info);
 
        switch(device_type) {
-               case DEVICE_TYPE_TUN:
-                       packet->data[10] = packet->data[11] = 0;
-                       if(write(device_fd, packet->data + 10, packet->len - 10) < 0) {
-                               logger(LOG_ERR, "Can't write to %s %s: %s", device_info, device,
-                                          strerror(errno));
-                               return false;
-                       }
-                       break;
-               case DEVICE_TYPE_TAP:
-                       if(write(device_fd, packet->data, packet->len) < 0) {
-                               logger(LOG_ERR, "Can't write to %s %s: %s", device_info, device,
-                                          strerror(errno));
-                               return false;
-                       }
-                       break;
-               case DEVICE_TYPE_ETHERTAP:
-                       *(short int *)(packet->data - 2) = packet->len;
-
-                       if(write(device_fd, packet->data - 2, packet->len + 2) < 0) {
-                               logger(LOG_ERR, "Can't write to %s %s: %s", device_info, device,
-                                          strerror(errno));
-                               return false;
-                       }
-                       break;
+       case DEVICE_TYPE_TUN:
+               packet->data[10] = packet->data[11] = 0;
+
+               if(write(device_fd, packet->data + 10, packet->len - 10) < 0) {
+                       logger(LOG_ERR, "Can't write to %s %s: %s", device_info, device,
+                              strerror(errno));
+                       return false;
+               }
+
+               break;
+
+       case DEVICE_TYPE_TAP:
+               if(write(device_fd, packet->data, packet->len) < 0) {
+                       logger(LOG_ERR, "Can't write to %s %s: %s", device_info, device,
+                              strerror(errno));
+                       return false;
+               }
+
+               break;
+
+       case DEVICE_TYPE_ETHERTAP:
+               memcpy(packet->data - 2, &packet->len, 2);
+
+               if(write(device_fd, packet->data - 2, packet->len + 2) < 0) {
+                       logger(LOG_ERR, "Can't write to %s %s: %s", device_info, device,
+                              strerror(errno));
+                       return false;
+               }
+
+               break;
        }
 
        device_total_out += packet->len;
@@ -203,8 +256,16 @@ bool write_packet(vpn_packet_t *packet) {
        return true;
 }
 
-void dump_device_stats(void) {
+static void dump_device_stats(void) {
        logger(LOG_DEBUG, "Statistics for %s %s:", device_info, device);
-       logger(LOG_DEBUG, " total bytes in:  %10d", device_total_in);
-       logger(LOG_DEBUG, " total bytes out: %10d", device_total_out);
+       logger(LOG_DEBUG, " total bytes in:  %10"PRIu64, device_total_in);
+       logger(LOG_DEBUG, " total bytes out: %10"PRIu64, device_total_out);
 }
+
+const devops_t os_devops = {
+       .setup = setup_device,
+       .close = close_device,
+       .read = read_packet,
+       .write = write_packet,
+       .dump_stats = dump_device_stats,
+};