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25#include "qemu/osdep.h"
26#include "qemu-common.h"
27#include "qapi/error.h"
28#include "tap_int.h"
29#include "qemu/cutils.h"
30#include "sysemu/sysemu.h"
31#include "qemu/error-report.h"
32
33#if defined(__NetBSD__) || defined(__FreeBSD__)
34#include <sys/ioctl.h>
35#include <net/if.h>
36#include <net/if_tap.h>
37#endif
38
39#if defined(__OpenBSD__)
40#include <sys/param.h>
41#endif
42
43#ifndef __FreeBSD__
44int tap_open(char *ifname, int ifname_size, int *vnet_hdr,
45 int vnet_hdr_required, int mq_required, Error **errp)
46{
47 int fd;
48#ifdef TAPGIFNAME
49 struct ifreq ifr;
50#else
51 char *dev;
52 struct stat s;
53#endif
54
55
56 int i;
57 char dname[100];
58
59 for (i = 0; i < 10; i++) {
60 if (*ifname) {
61 snprintf(dname, sizeof dname, "/dev/%s", ifname);
62 } else {
63#if defined(__OpenBSD__) && OpenBSD < 201605
64 snprintf(dname, sizeof dname, "/dev/tun%d", i);
65#else
66 snprintf(dname, sizeof dname, "/dev/tap%d", i);
67#endif
68 }
69 TFR(fd = open(dname, O_RDWR));
70 if (fd >= 0) {
71 break;
72 }
73 else if (errno == ENXIO || errno == ENOENT) {
74 break;
75 }
76 if (*ifname) {
77 break;
78 }
79 }
80 if (fd < 0) {
81 error_setg_errno(errp, errno, "could not open %s", dname);
82 return -1;
83 }
84
85#ifdef TAPGIFNAME
86 if (ioctl(fd, TAPGIFNAME, (void *)&ifr) < 0) {
87 error_setg_errno(errp, errno, "could not get tap name");
88 return -1;
89 }
90 pstrcpy(ifname, ifname_size, ifr.ifr_name);
91#else
92 if (fstat(fd, &s) < 0) {
93 error_setg_errno(errp, errno, "could not stat %s", dname);
94 return -1;
95 }
96 dev = devname(s.st_rdev, S_IFCHR);
97 pstrcpy(ifname, ifname_size, dev);
98#endif
99
100 if (*vnet_hdr) {
101
102 *vnet_hdr = 0;
103
104 if (vnet_hdr_required && !*vnet_hdr) {
105 error_setg(errp, "vnet_hdr=1 requested, but no kernel "
106 "support for IFF_VNET_HDR available");
107 close(fd);
108 return -1;
109 }
110 }
111 fcntl(fd, F_SETFL, O_NONBLOCK);
112 return fd;
113}
114
115#else
116
117#define PATH_NET_TAP "/dev/tap"
118
119static int tap_open_clone(char *ifname, int ifname_size, Error **errp)
120{
121 int fd, s, ret;
122 struct ifreq ifr;
123
124 TFR(fd = open(PATH_NET_TAP, O_RDWR));
125 if (fd < 0) {
126 error_setg_errno(errp, errno, "could not open %s", PATH_NET_TAP);
127 return -1;
128 }
129
130 memset(&ifr, 0, sizeof(ifr));
131
132 ret = ioctl(fd, TAPGIFNAME, (void *)&ifr);
133 if (ret < 0) {
134 error_setg_errno(errp, errno, "could not get tap interface name");
135 close(fd);
136 return -1;
137 }
138
139 if (ifname[0] != '\0') {
140
141 s = socket(AF_LOCAL, SOCK_DGRAM, 0);
142 if (s < 0) {
143 error_setg_errno(errp, errno,
144 "could not open socket to set interface name");
145 close(fd);
146 return -1;
147 }
148 ifr.ifr_data = ifname;
149 ret = ioctl(s, SIOCSIFNAME, (void *)&ifr);
150 close(s);
151 if (ret < 0) {
152 error_setg(errp, "could not set tap interface name");
153 close(fd);
154 return -1;
155 }
156 } else {
157 pstrcpy(ifname, ifname_size, ifr.ifr_name);
158 }
159
160 return fd;
161}
162
163int tap_open(char *ifname, int ifname_size, int *vnet_hdr,
164 int vnet_hdr_required, int mq_required, Error **errp)
165{
166 int fd = -1;
167
168
169 if (ifname[0] != '\0') {
170 char dname[100];
171 snprintf(dname, sizeof dname, "/dev/%s", ifname);
172 TFR(fd = open(dname, O_RDWR));
173 if (fd < 0 && errno != ENOENT) {
174 error_setg_errno(errp, errno, "could not open %s", dname);
175 return -1;
176 }
177 }
178
179 if (fd < 0) {
180
181 if ((fd = tap_open_clone(ifname, ifname_size, errp)) < 0) {
182 return -1;
183 }
184 }
185
186 if (*vnet_hdr) {
187
188 *vnet_hdr = 0;
189
190 if (vnet_hdr_required && !*vnet_hdr) {
191 error_setg(errp, "vnet_hdr=1 requested, but no kernel "
192 "support for IFF_VNET_HDR available");
193 goto error;
194 }
195 }
196 if (mq_required) {
197 error_setg(errp, "mq_required requested, but no kernel support"
198 " for IFF_MULTI_QUEUE available");
199 goto error;
200 }
201
202 fcntl(fd, F_SETFL, O_NONBLOCK);
203 return fd;
204
205error:
206 close(fd);
207 return -1;
208}
209#endif
210
211void tap_set_sndbuf(int fd, const NetdevTapOptions *tap, Error **errp)
212{
213}
214
215int tap_probe_vnet_hdr(int fd)
216{
217 return 0;
218}
219
220int tap_probe_has_ufo(int fd)
221{
222 return 0;
223}
224
225int tap_probe_vnet_hdr_len(int fd, int len)
226{
227 return 0;
228}
229
230void tap_fd_set_vnet_hdr_len(int fd, int len)
231{
232}
233
234int tap_fd_set_vnet_le(int fd, int is_le)
235{
236 return -EINVAL;
237}
238
239int tap_fd_set_vnet_be(int fd, int is_be)
240{
241 return -EINVAL;
242}
243
244void tap_fd_set_offload(int fd, int csum, int tso4,
245 int tso6, int ecn, int ufo)
246{
247}
248
249int tap_fd_enable(int fd)
250{
251 return -1;
252}
253
254int tap_fd_disable(int fd)
255{
256 return -1;
257}
258
259int tap_fd_get_ifname(int fd, char *ifname)
260{
261 return -1;
262}
263