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 "net/tap.h"
  26 #include "qemu-common.h"
  27 #include "sysemu.h"
  28
  29 #ifdef __NetBSD__
  30 #include <net/if_tap.h>
  31 #endif
  32
  33 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__)
  34 #include <libutil.h>
  35 #else
  36 #include <util.h>
  37 #endif
  38
  39 #if defined(__OpenBSD__)
  40 #include <util.h>
  41 #endif
  42
  43 int tap_open(char *ifname, int ifname_size, int *vnet_hdr, int vnet_hdr_required)
  44 {
  45     int fd;
  46     char *dev;
  47     struct stat s;
  48
  49 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
  50     /* if no ifname is given, always start the search from tap0. */
  51     int i;
  52     char dname[100];
  53
  54     for (i = 0; i < 10; i++) {
  55         if (*ifname) {
  56             snprintf(dname, sizeof dname, "/dev/%s", ifname);
  57         } else {
  58             snprintf(dname, sizeof dname, "/dev/tap%d", i);
  59         }
  60         TFR(fd = open(dname, O_RDWR));
  61         if (fd >= 0) {
  62             break;
  63         }
  64         else if (errno == ENXIO || errno == ENOENT) {
  65             break;
  66         }
  67         if (*ifname) {
  68             break;
  69         }
  70     }
  71     if (fd < 0) {
  72         qemu_error("warning: could not open %s (%s): no virtual network emulation\n", dname, strerror(errno));
  73         return -1;
  74     }
  75 #else
  76     TFR(fd = open("/dev/tap", O_RDWR));
  77     if (fd < 0) {
  78         fprintf(stderr, "warning: could not open /dev/tap: no virtual network emulation\n");
  79         return -1;
  80     }
  81 #endif
  82
  83     fstat(fd, &s);
  84     dev = devname(s.st_rdev, S_IFCHR);
  85     pstrcpy(ifname, ifname_size, dev);
  86
  87     if (*vnet_hdr) {
  88         /* BSD doesn't have IFF_VNET_HDR */
  89         *vnet_hdr = 0;
  90
  91         if (vnet_hdr_required && !*vnet_hdr) {
  92             qemu_error("vnet_hdr=1 requested, but no kernel "
  93                        "support for IFF_VNET_HDR available");
  94             close(fd);
  95             return -1;
  96         }
  97     }
  98     fcntl(fd, F_SETFL, O_NONBLOCK);
  99     return fd;
 100 }
 101
 102 int tap_set_sndbuf(int fd, QemuOpts *opts)
 103 {
 104     return 0;
 105 }
 106
 107 int tap_probe_vnet_hdr(int fd)
 108 {
 109     return 0;
 110 }
 111
 112 int tap_probe_has_ufo(int fd)
 113 {
 114     return 0;
 115 }
 116
 117 void tap_fd_set_offload(int fd, int csum, int tso4,
 118                         int tso6, int ecn, int ufo)
 119 {
 120 }