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 #include "qemu-error.h"
  29
  30 #ifdef __NetBSD__
  31 #include <net/if_tap.h>
  32 #endif
  33
  34 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__)
  35 #include <libutil.h>
  36 #else
  37 #include <util.h>
  38 #endif
  39
  40 int tap_open(char *ifname, int ifname_size, int *vnet_hdr, int vnet_hdr_required)
  41 {
  42     int fd;
  43     char *dev;
  44     struct stat s;
  45
  46 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
  47     /* if no ifname is given, always start the search from tap0. */
  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             snprintf(dname, sizeof dname, "/dev/tap%d", i);
  56         }
  57         TFR(fd = open(dname, O_RDWR));
  58         if (fd >= 0) {
  59             break;
  60         }
  61         else if (errno == ENXIO || errno == ENOENT) {
  62             break;
  63         }
  64         if (*ifname) {
  65             break;
  66         }
  67     }
  68     if (fd < 0) {
  69         error_report("warning: could not open %s (%s): no virtual network emulation",
  70                    dname, strerror(errno));
  71         return -1;
  72     }
  73 #else
  74     TFR(fd = open("/dev/tap", O_RDWR));
  75     if (fd < 0) {
  76         fprintf(stderr, "warning: could not open /dev/tap: no virtual network emulation\n");
  77         return -1;
  78     }
  79 #endif
  80
  81     fstat(fd, &s);
  82     dev = devname(s.st_rdev, S_IFCHR);
  83     pstrcpy(ifname, ifname_size, dev);
  84
  85     if (*vnet_hdr) {
  86         /* BSD doesn't have IFF_VNET_HDR */
  87         *vnet_hdr = 0;
  88
  89         if (vnet_hdr_required && !*vnet_hdr) {
  90             error_report("vnet_hdr=1 requested, but no kernel "
  91                          "support for IFF_VNET_HDR available");
  92             close(fd);
  93             return -1;
  94         }
  95     }
  96     fcntl(fd, F_SETFL, O_NONBLOCK);
  97     return fd;
  98 }
  99
 100 int tap_set_sndbuf(int fd, QemuOpts *opts)
 101 {
 102     return 0;
 103 }
 104
 105 int tap_probe_vnet_hdr(int fd)
 106 {
 107     return 0;
 108 }
 109
 110 int tap_probe_has_ufo(int fd)
 111 {
 112     return 0;
 113 }
 114
 115 int tap_probe_vnet_hdr_len(int fd, int len)
 116 {
 117     return 0;
 118 }
 119
 120 void tap_fd_set_vnet_hdr_len(int fd, int len)
 121 {
 122 }
 123
 124 void tap_fd_set_offload(int fd, int csum, int tso4,
 125                         int tso6, int ecn, int ufo)
 126 {
 127 }