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/* |
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device.c -- Interaction with Linux ethertap and tun/tap device |
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Copyright (C) 2001-2003 Ivo Timmermans <ivo@o2w.nl>, |
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2001-2003 Guus Sliepen <guus@sliepen.eu.org> |
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|
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This program is free software; you can redistribute it and/or modify |
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it under the terms of the GNU General Public License as published by |
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the Free Software Foundation; either version 2 of the License, or |
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(at your option) any later version. |
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|
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This program is distributed in the hope that it will be useful, |
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but WITHOUT ANY WARRANTY; without even the implied warranty of |
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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GNU General Public License for more details. |
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|
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You should have received a copy of the GNU General Public License |
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along with this program; if not, write to the Free Software |
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Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
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|
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$Id: device.c,v 1.1.2.20 2003/07/22 20:55:21 guus Exp $ |
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*/ |
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|
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|
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#ifdef HAVE_TUNTAP |
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#ifdef LINUX_IF_TUN_H |
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#include LINUX_IF_TUN_H |
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#else |
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#include <linux/if_tun.h> |
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#endif |
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#define DEFAULT_DEVICE "/dev/net/tun" |
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#else |
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#define DEFAULT_DEVICE "/dev/tap0" |
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#endif |
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|
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|
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typedef enum device_type_t { |
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DEVICE_TYPE_ETHERTAP, |
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DEVICE_TYPE_TUN, |
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DEVICE_TYPE_TAP, |
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} device_type_t; |
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|
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int device_fd = -1; |
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device_type_t device_type; |
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char *device; |
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char *iface; |
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char ifrname[IFNAMSIZ]; |
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char *device_info; |
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|
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int device_total_in = 0; |
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int device_total_out = 0; |
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|
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bool setup_device(void) |
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{ |
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struct ifreq ifr; |
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|
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cp(); |
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|
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if(!get_config_string(lookup_config(config_tree, "Device"), &device)) |
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device = DEFAULT_DEVICE; |
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|
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if(!get_config_string(lookup_config(config_tree, "Interface"), &iface)) |
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#ifdef HAVE_TUNTAP |
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iface = netname; |
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#else |
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iface = rindex(device, '/') ? rindex(device, '/') + 1 : device; |
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#endif |
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device_fd = open(device, O_RDWR | O_NONBLOCK); |
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|
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if(device_fd < 0) { |
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logger(LOG_ERR, _("Could not open %s: %s"), device, strerror(errno)); |
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return false; |
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} |
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|
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#ifdef HAVE_TUNTAP |
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/* Ok now check if this is an old ethertap or a new tun/tap thingie */ |
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|
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memset(&ifr, 0, sizeof(ifr)); |
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if(routing_mode == RMODE_ROUTER) { |
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ifr.ifr_flags = IFF_TUN; |
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device_type = DEVICE_TYPE_TUN; |
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device_info = _("Linux tun/tap device (tun mode)"); |
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} else { |
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ifr.ifr_flags = IFF_TAP | IFF_NO_PI; |
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device_type = DEVICE_TYPE_TAP; |
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device_info = _("Linux tun/tap device (tap mode)"); |
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} |
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|
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if(iface) |
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strncpy(ifr.ifr_name, iface, IFNAMSIZ); |
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|
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if(!ioctl(device_fd, TUNSETIFF, (void *) &ifr)) { |
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strncpy(ifrname, ifr.ifr_name, IFNAMSIZ); |
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iface = ifrname; |
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} else if(!ioctl(device_fd, (('T' << 8) | 202), (void *) &ifr)) { |
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logger(LOG_WARNING, _("Old ioctl() request was needed for %s"), device); |
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strncpy(ifrname, ifr.ifr_name, IFNAMSIZ); |
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iface = ifrname; |
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} else |
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#endif |
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{ |
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if(routing_mode == RMODE_ROUTER) |
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overwrite_mac = true; |
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device_info = _("Linux ethertap device"); |
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device_type = DEVICE_TYPE_ETHERTAP; |
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iface = rindex(device, '/') ? rindex(device, '/') + 1 : device; |
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} |
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|
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logger(LOG_INFO, _("%s is a %s"), device, device_info); |
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|
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return true; |
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} |
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|
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void close_device(void) |
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{ |
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cp(); |
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|
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close(device_fd); |
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} |
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|
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bool read_packet(vpn_packet_t *packet) |
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{ |
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int lenin; |
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|
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cp(); |
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|
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switch(device_type) { |
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case DEVICE_TYPE_TUN: |
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lenin = read(device_fd, packet->data + 10, MTU - 10); |
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|
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if(lenin <= 0) { |
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logger(LOG_ERR, _("Error while reading from %s %s: %s"), |
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device_info, device, strerror(errno)); |
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return false; |
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} |
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|
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packet->len = lenin + 10; |
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break; |
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case DEVICE_TYPE_TAP: |
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lenin = read(device_fd, packet->data, MTU); |
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|
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if(lenin <= 0) { |
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logger(LOG_ERR, _("Error while reading from %s %s: %s"), |
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device_info, device, strerror(errno)); |
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return false; |
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} |
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|
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packet->len = lenin; |
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break; |
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case DEVICE_TYPE_ETHERTAP: |
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lenin = read(device_fd, packet->data - 2, MTU + 2); |
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|
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if(lenin <= 0) { |
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logger(LOG_ERR, _("Error while reading from %s %s: %s"), |
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device_info, device, strerror(errno)); |
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return false; |
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} |
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|
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packet->len = lenin - 2; |
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break; |
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} |
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|
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device_total_in += packet->len; |
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|
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ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len, |
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device_info); |
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|
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return true; |
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} |
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|
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bool write_packet(vpn_packet_t *packet) |
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{ |
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cp(); |
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|
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ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"), |
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packet->len, device_info); |
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|
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switch(device_type) { |
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case DEVICE_TYPE_TUN: |
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packet->data[10] = packet->data[11] = 0; |
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if(write(device_fd, packet->data + 10, packet->len - 10) < 0) { |
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logger(LOG_ERR, _("Can't write to %s %s: %s"), device_info, device, |
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strerror(errno)); |
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return false; |
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} |
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break; |
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case DEVICE_TYPE_TAP: |
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if(write(device_fd, packet->data, packet->len) < 0) { |
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logger(LOG_ERR, _("Can't write to %s %s: %s"), device_info, device, |
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strerror(errno)); |
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return false; |
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} |
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break; |
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case DEVICE_TYPE_ETHERTAP: |
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*(short int *)(packet->data - 2) = packet->len; |
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|
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if(write(device_fd, packet->data - 2, packet->len + 2) < 0) { |
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logger(LOG_ERR, _("Can't write to %s %s: %s"), device_info, device, |
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strerror(errno)); |
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return false; |
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} |
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break; |
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} |
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|
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device_total_out += packet->len; |
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|
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return true; |
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} |
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|
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void dump_device_stats(void) |
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{ |
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cp(); |
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|
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logger(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device); |
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logger(LOG_DEBUG, _(" total bytes in: %10d"), device_total_in); |
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logger(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out); |
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} |
