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