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