Generic device driver for *BSD and MacOS/X

diff --git a/src/bsd/device.c b/src/bsd/device.c
new file mode 100644 (file)
index 0000000..045fc18
--- /dev/null
+++ b/src/bsd/device.c
@@ -0,0 +1,283 @@
+/*
+    device.c -- Interaction BSD tun/tap device
+    Copyright (C) 2001-2004 Ivo Timmermans <ivo@tinc-vpn.org>,
+                  2001-2004 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
+    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.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+    $Id: device.c 1398 2004-11-01 15:18:53Z guus $
+*/
+
+#include "system.h"
+
+#include "conf.h"
+#include "logger.h"
+#include "net.h"
+#include "route.h"
+#include "utils.h"
+
+#define DEFAULT_DEVICE "/dev/tun0"
+
+typedef enum device_type {
+       DEVICE_TYPE_TUN,
+       DEVICE_TYPE_TUNIFHEAD,
+       DEVICE_TYPE_TAP,
+} device_type_t;
+
+int device_fd = -1;
+char *device;
+char *iface;
+char *device_info;
+static int device_total_in = 0;
+static int device_total_out = 0;
+#ifdef HAVE_OPENBSD
+static device_type_t device_type = DEVICE_TYPE_TUNIFHEAD;
+#else
+static device_type_t device_type = DEVICE_TYPE_TUN;
+#endif
+
+bool setup_device(void) {
+#ifdef TUNSIFHEAD
+       const int zero = 0;
+       const int one = 1;
+#endif
+       char *type;
+
+       cp();
+
+       if(!get_config_string(lookup_config(config_tree, "Device"), &device))
+               device = DEFAULT_DEVICE;
+
+       if(!get_config_string(lookup_config(config_tree, "Interface"), &iface))
+               iface = rindex(device, '/') ? rindex(device, '/') + 1 : device;
+
+       if((device_fd = open(device, O_RDWR | O_NONBLOCK)) < 0) {
+               logger(LOG_ERR, _("Could not open %s: %s"), device, strerror(errno));
+               return false;
+       }
+
+       if(get_config_string(lookup_config(config_tree, "DeviceType"), &type)) {
+               if(!strcasecmp(type, "tun"))
+                       /* use default */;      
+               else if(!strcasecmp(type, "tunnohead"))
+                       device_type = DEVICE_TYPE_TUN;
+               else if(!strcasecmp(type, "tunifhead"))
+                       device_type = DEVICE_TYPE_TUNIFHEAD;
+               else if(!strcasecmp(type, "tap"))
+                       device_type = DEVICE_TYPE_TAP;
+               else {
+                       logger(LOG_ERR, _("Unknown device type %s!"), type);
+                       return false;
+               }
+       } else {
+               if(strstr(device, "tap"))
+                       device_type = DEVICE_TYPE_TAP;
+       }
+
+       switch(device_type) {
+               default:
+                       device_type = DEVICE_TYPE_TUN;
+               case DEVICE_TYPE_TUN:
+#ifdef TUNSIFHEAD
+                       if(ioctl(device_fd, TUNSIFHEAD, &zero, sizeof zero) == -1) {
+                               logger(LOG_ERR, _("System call `%s' failed: %s"), "ioctl", strerror(errno));
+                               return false;
+                       }
+#endif
+                       device_info = _("Generic BSD tun device");
+                       break;
+               case DEVICE_TYPE_TUNIFHEAD:
+#ifdef TUNSIFHEAD
+                       if(ioctl(device_fd, TUNSIFHEAD, &one, sizeof one) == -1) {
+                               logger(LOG_ERR, _("System call `%s' failed: %s"), "ioctl", strerror(errno));
+                               return false;
+                       }
+#endif
+                       device_info = _("Generic BSD tun device");
+                       break;
+               case DEVICE_TYPE_TAP:
+                       if(routing_mode == RMODE_ROUTER)
+                               overwrite_mac = true;
+                       device_info = _("Generic BSD tap device");
+                       break;
+       }
+
+       logger(LOG_INFO, _("%s is a %s"), device, device_info);
+
+       return true;
+}
+
+void close_device(void) {
+       cp();
+
+       close(device_fd);
+}
+
+bool read_packet(vpn_packet_t *packet) {
+       int lenin;
+
+       cp();
+
+       switch(device_type) {
+               case DEVICE_TYPE_TUN:
+                       if((lenin = read(device_fd, packet->data + 14, MTU - 14)) <= 0) {
+                               logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
+                                          device, strerror(errno));
+                               return false;
+                       }
+
+                       switch(packet->data[14] >> 4) {
+                               case 4:
+                                       packet->data[12] = 0x08;
+                                       packet->data[13] = 0x00;
+                                       break;
+                               case 6:
+                                       packet->data[12] = 0x86;
+                                       packet->data[13] = 0xDD;
+                                       break;
+                               default:
+                                       ifdebug(TRAFFIC) logger(LOG_ERR,
+                                                          _ ("Unknown IP version %d while reading packet from %s %s"),
+                                                          packet->data[14] >> 4, device_info, device);
+                                       return false;
+                       }
+
+                       packet->len = lenin + 14;
+                       break;
+
+               case DEVICE_TYPE_TUNIFHEAD: {
+                       u_int32_t type;
+                       struct iovec vector[2] = {{&type, sizeof(type)}, {packet->data + 14, MTU - 14}};
+
+                       if((lenin = readv(device_fd, vector, 2)) <= 0) {
+                               logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
+                                          device, strerror(errno));
+                               return false;
+                       }
+
+                       switch (ntohl(type)) {
+                               case AF_INET:
+                                       packet->data[12] = 0x08;
+                                       packet->data[13] = 0x00;
+                                       break;
+
+                               case AF_INET6:
+                                       packet->data[12] = 0x86;
+                                       packet->data[13] = 0xDD;
+                                       break;
+
+                               default:
+                                       ifdebug(TRAFFIC) logger(LOG_ERR,
+                                                          _ ("Unknown address family %x while reading packet from %s %s"),
+                                                          ntohl(type), device_info, device);
+                                       return false;
+                       }
+
+                       packet->len = lenin + 10;
+                       break;
+               }
+
+               case DEVICE_TYPE_TAP:
+                       if((lenin = read(device_fd, packet->data, MTU)) <= 0) {
+                               logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
+                                          device, strerror(errno));
+                               return false;
+                       }
+
+                       packet->len = lenin;
+                       break;
+
+               default:
+                       return false;
+       }
+               
+       device_total_in += packet->len;
+
+       ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Read packet of %d bytes from %s"),
+                          packet->len, device_info);
+
+       return true;
+}
+
+bool write_packet(vpn_packet_t *packet)
+{
+       cp();
+
+       ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
+                          packet->len, device_info);
+
+       switch(device_type) {
+               case DEVICE_TYPE_TUN:
+                       if(write(device_fd, packet->data + 14, packet->len - 14) < 0) {
+                               logger(LOG_ERR, _("Error while writing to %s %s: %s"), device_info,
+                                          device, strerror(errno));
+                               return false;
+                       }
+                       break;
+
+               case DEVICE_TYPE_TUNIFHEAD: {
+                       u_int32_t type;
+                       struct iovec vector[2] = {{&type, sizeof(type)}, {packet->data + 14, MTU - 14}};
+                       int af;
+                       
+                       af = (packet->data[12] << 8) + packet->data[13];
+
+                       switch (af) {
+                               case 0x0800:
+                                       type = htonl(AF_INET);
+                                       break;
+                               case 0x86DD:
+                                       type = htonl(AF_INET6);
+                                       break;
+                               default:
+                                       ifdebug(TRAFFIC) logger(LOG_ERR,
+                                                          _("Unknown address family %x while writing packet to %s %s"),
+                                                          af, device_info, device);
+                                       return false;
+                       }
+
+                       if(writev(device_fd, vector, 2) < 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, _("Error while writing to %s %s: %s"), device_info,
+                                          device, strerror(errno));
+                               return false;
+                       }
+                       break;
+
+               default:
+                       return false;
+       }
+
+       device_total_out += packet->len;
+
+       return true;
+}
+
+void dump_device_stats(void)
+{
+       cp();
+
+       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);
+}