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,
  37              int vnet_hdr_required, int mq_required)
  38 {
  39     int fd;
  40 #ifdef TAPGIFNAME
  41     struct ifreq ifr;
  42 #else
  43     char *dev;
  44     struct stat s;
  45 #endif
  46
  47 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || \
  48     defined(__OpenBSD__) || defined(__APPLE__)
  49     /* if no ifname is given, always start the search from tap0/tun0. */
  50     int i;
  51     char dname[100];
  52
  53     for (i = 0; i < 10; i++) {
  54         if (*ifname) {
  55             snprintf(dname, sizeof dname, "/dev/%s", ifname);
  56         } else {
  57 #if defined(__OpenBSD__)
  58             snprintf(dname, sizeof dname, "/dev/tun%d", i);
  59 #else
  60             snprintf(dname, sizeof dname, "/dev/tap%d", i);
  61 #endif
  62         }
  63         TFR(fd = open(dname, O_RDWR));
  64         if (fd >= 0) {
  65             break;
  66         }
  67         else if (errno == ENXIO || errno == ENOENT) {
  68             break;
  69         }
  70         if (*ifname) {
  71             break;
  72         }
  73     }
  74     if (fd < 0) {
  75         error_report("warning: could not open %s (%s): no virtual network emulation",
  76                    dname, strerror(errno));
  77         return -1;
  78     }
  79 #else
  80     TFR(fd = open("/dev/tap", O_RDWR));
  81     if (fd < 0) {
  82         fprintf(stderr,
  83             "warning: could not open /dev/tap: no virtual network emulation: %s\n",
  84             strerror(errno));
  85         return -1;
  86     }
  87 #endif
  88
  89 #ifdef TAPGIFNAME
  90     if (ioctl(fd, TAPGIFNAME, (void *)&ifr) < 0) {
  91         fprintf(stderr, "warning: could not get tap name: %s\n",
  92             strerror(errno));
  93         return -1;
  94     }
  95     pstrcpy(ifname, ifname_size, ifr.ifr_name);
  96 #else
  97     if (fstat(fd, &s) < 0) {
  98         fprintf(stderr,
  99             "warning: could not stat /dev/tap: no virtual network emulation: %s\n",
 100             strerror(errno));
 101         return -1;
 102     }
 103     dev = devname(s.st_rdev, S_IFCHR);
 104     pstrcpy(ifname, ifname_size, dev);
 105 #endif
 106
 107     if (*vnet_hdr) {
 108         /* BSD doesn't have IFF_VNET_HDR */
 109         *vnet_hdr = 0;
 110
 111         if (vnet_hdr_required && !*vnet_hdr) {
 112             error_report("vnet_hdr=1 requested, but no kernel "
 113                          "support for IFF_VNET_HDR available");
 114             close(fd);
 115             return -1;
 116         }
 117     }
 118     fcntl(fd, F_SETFL, O_NONBLOCK);
 119     return fd;
 120 }
 121
 122 int tap_set_sndbuf(int fd, const NetdevTapOptions *tap)
 123 {
 124     return 0;
 125 }
 126
 127 int tap_probe_vnet_hdr(int fd)
 128 {
 129     return 0;
 130 }
 131
 132 int tap_probe_has_ufo(int fd)
 133 {
 134     return 0;
 135 }
 136
 137 int tap_probe_vnet_hdr_len(int fd, int len)
 138 {
 139     return 0;
 140 }
 141
 142 void tap_fd_set_vnet_hdr_len(int fd, int len)
 143 {
 144 }
 145
 146 void tap_fd_set_offload(int fd, int csum, int tso4,
 147                         int tso6, int ecn, int ufo)
 148 {
 149 }
 150
 151 int tap_fd_enable(int fd)
 152 {
 153     return -1;
 154 }
 155
 156 int tap_fd_disable(int fd)
 157 {
 158     return -1;
 159 }
 160
 161 int tap_fd_get_ifname(int fd, char *ifname)
 162 {
 163     return -1;
 164 }