net/tap-bsd.c

   1 /*
   2  * QEMU System Emulator
   3  *
   4  * Copyright (c) 2003-2008 Fabrice Bellard
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24
  25 #include "tap_int.h"
  26 #include "qemu-common.h"
  27 #include "sysemu/sysemu.h"
  28 #include "qemu/error-report.h"
  29
  30 #ifdef __NetBSD__
  31 #include <sys/ioctl.h>
  32 #include <net/if.h>
  33 #include <net/if_tap.h>
  34 #endif
  35
  36 int tap_open(char *ifname, int ifname_size, int *vnet_hdr, int vnet_hdr_required)
  37 {
  38     int fd;
  39 #ifdef TAPGIFNAME
  40     struct ifreq ifr;
  41 #else
  42     char *dev;
  43     struct stat s;
  44 #endif
  45
  46 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__OpenBSD__)
  47     /* if no ifname is given, always start the search from tap0/tun0. */
  48     int i;
  49     char dname[100];
  50
  51     for (i = 0; i < 10; i++) {
  52         if (*ifname) {
  53             snprintf(dname, sizeof dname, "/dev/%s", ifname);
  54         } else {
  55 #if defined(__OpenBSD__)
  56             snprintf(dname, sizeof dname, "/dev/tun%d", i);
  57 #else
  58             snprintf(dname, sizeof dname, "/dev/tap%d", i);
  59 #endif
  60         }
  61         TFR(fd = open(dname, O_RDWR));
  62         if (fd >= 0) {
  63             break;
  64         }
  65         else if (errno == ENXIO || errno == ENOENT) {
  66             break;
  67         }
  68         if (*ifname) {
  69             break;
  70         }
  71     }
  72     if (fd < 0) {
  73         error_report("warning: could not open %s (%s): no virtual network emulation",
  74                    dname, strerror(errno));
  75         return -1;
  76     }
  77 #else
  78     TFR(fd = open("/dev/tap", O_RDWR));
  79     if (fd < 0) {
  80         fprintf(stderr,
  81             "warning: could not open /dev/tap: no virtual network emulation: %s\n",
  82             strerror(errno));
  83         return -1;
  84     }
  85 #endif
  86
  87 #ifdef TAPGIFNAME
  88     if (ioctl(fd, TAPGIFNAME, (void *)&ifr) < 0) {
  89         fprintf(stderr, "warning: could not get tap name: %s\n",
  90             strerror(errno));
  91         return -1;
  92     }
  93     pstrcpy(ifname, ifname_size, ifr.ifr_name);
  94 #else
  95     if (fstat(fd, &s) < 0) {
  96         fprintf(stderr,
  97             "warning: could not stat /dev/tap: no virtual network emulation: %s\n",
  98             strerror(errno));
  99         return -1;
 100     }
 101     dev = devname(s.st_rdev, S_IFCHR);
 102     pstrcpy(ifname, ifname_size, dev);
 103 #endif
 104
 105     if (*vnet_hdr) {
 106         /* BSD doesn't have IFF_VNET_HDR */
 107         *vnet_hdr = 0;
 108
 109         if (vnet_hdr_required && !*vnet_hdr) {
 110             error_report("vnet_hdr=1 requested, but no kernel "
 111                          "support for IFF_VNET_HDR available");
 112             close(fd);
 113             return -1;
 114         }
 115     }
 116     fcntl(fd, F_SETFL, O_NONBLOCK);
 117     return fd;
 118 }
 119
 120 int tap_set_sndbuf(int fd, const NetdevTapOptions *tap)
 121 {
 122     return 0;
 123 }
 124
 125 int tap_probe_vnet_hdr(int fd)
 126 {
 127     return 0;
 128 }
 129
 130 int tap_probe_has_ufo(int fd)
 131 {
 132     return 0;
 133 }
 134
 135 int tap_probe_vnet_hdr_len(int fd, int len)
 136 {
 137     return 0;
 138 }
 139
 140 void tap_fd_set_vnet_hdr_len(int fd, int len)
 141 {
 142 }
 143
 144 void tap_fd_set_offload(int fd, int csum, int tso4,
 145                         int tso6, int ecn, int ufo)
 146 {
 147 }