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(__DragonFly__) 34 #include <libutil.h> 35 #else 36 #include <util.h> 37 #endif 38 #if defined (__GLIBC__) && defined (__FreeBSD_kernel__) 39 #include <freebsd/stdlib.h> 40 #endif 41 42 #if defined(__OpenBSD__) 43 #include <util.h> 44 #endif 45 46 int tap_open(char *ifname, int ifname_size, int *vnet_hdr, int vnet_hdr_required) 47 { 48 int fd; 49 char *dev; 50 struct stat s; 51 52 #ifdef __FreeBSD__ 53 /* if no ifname is given, always start the search from tap0. */ 54 int i; 55 char dname[100]; 56 57 for (i = 0; i < 10; i++) { 58 if (*ifname) { 59 snprintf(dname, sizeof dname, "/dev/%s", ifname); 60 } else { 61 snprintf(dname, sizeof dname, "/dev/tap%d", i); 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 qemu_error("warning: could not open %s (%s): no virtual network emulation\n", dname, strerror(errno)); 76 return -1; 77 } 78 #else 79 TFR(fd = open("/dev/tap", O_RDWR)); 80 if (fd < 0) { 81 fprintf(stderr, "warning: could not open /dev/tap: no virtual network emulation\n"); 82 return -1; 83 } 84 #endif 85 86 fstat(fd, &s); 87 dev = devname(s.st_rdev, S_IFCHR); 88 pstrcpy(ifname, ifname_size, dev); 89 90 if (*vnet_hdr) { 91 /* BSD doesn't have IFF_VNET_HDR */ 92 *vnet_hdr = 0; 93 94 if (vnet_hdr_required && !*vnet_hdr) { 95 qemu_error("vnet_hdr=1 requested, but no kernel " 96 "support for IFF_VNET_HDR available"); 97 close(fd); 98 return -1; 99 } 100 } 101 fcntl(fd, F_SETFL, O_NONBLOCK); 102 return fd; 103 } 104 105 int tap_set_sndbuf(int fd, QemuOpts *opts) 106 { 107 return 0; 108 } 109 110 int tap_probe_vnet_hdr(int fd) 111 { 112 return 0; 113 } 114 115 int tap_probe_has_ufo(int fd) 116 { 117 return 0; 118 } 119 120 void tap_fd_set_offload(int fd, int csum, int tso4, 121 int tso6, int ecn, int ufo) 122 { 123 } 124