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