9 #include <sys/socket.h>
12 #include <linux/if_tun.h>
16 #define OVS_SOCK "/var/tun/pl-ovs.control"
22 fprintf(stderr, "%s: %s: %s", appname, msg, strerror(errno)); \
27 int send_vif_fd(int sock_fd, int vif_fd, char *vif_name)
31 struct cmsghdr *p_cmsg;
33 size_t cmsgbuf[CMSG_SPACE(sizeof(vif_fd)) / sizeof(size_t)];
37 msg.msg_control = cmsgbuf;
38 msg.msg_controllen = sizeof(cmsgbuf);
39 p_cmsg = CMSG_FIRSTHDR(&msg);
40 p_cmsg->cmsg_level = SOL_SOCKET;
41 p_cmsg->cmsg_type = SCM_RIGHTS;
42 p_cmsg->cmsg_len = CMSG_LEN(sizeof(vif_fd));
43 p_fds = (int *) CMSG_DATA(p_cmsg);
45 msg.msg_controllen = p_cmsg->cmsg_len;
52 /* Send the interface name as the iov */
53 vec.iov_base = vif_name;
54 vec.iov_len = strlen(vif_name)+1;
56 while ((retval = sendmsg(sock_fd, &msg, 0)) == -1 && errno == EINTR);
58 ERROR("sending file descriptor");
63 void send_fd(int p, int fd, char* vif_name)
67 struct sockaddr_un addr, accept_addr;
68 socklen_t addr_len = sizeof(accept_addr);
71 control_fd = socket(AF_UNIX, SOCK_STREAM, 0);
72 if (control_fd == -1 && errno != ENOENT) {
73 ERROR("Could not create UNIX socket");
76 memset(&addr, 0, sizeof(struct sockaddr_un));
78 addr.sun_family = AF_UNIX;
79 strncpy(addr.sun_path, OVS_SOCK,
80 sizeof(addr.sun_path) - 1);
82 if (unlink(OVS_SOCK) == -1 && errno != ENOENT) {
83 ERROR("Could not unlink " OVS_SOCK " control socket");
86 if (bind(control_fd, (struct sockaddr *) &addr,
87 sizeof(struct sockaddr_un)) == -1) {
88 ERROR("Could not bind to " OVS_SOCK " control socket");
91 if (listen(control_fd, 5) == -1) {
92 ERROR("listen on " OVS_SOCK " failed");
94 if (write(p, "1", 1) != 1) {
95 ERROR("writing on the synch pipe");
97 if ((accept_fd = accept(control_fd, (struct sockaddr*) &accept_addr,
99 ERROR("accept on " OVS_SOCK " failed");
101 send_vif_fd(accept_fd, fd, vif_name);
104 int main(int argc, char* argv[])
106 char if_name[IFNAMSIZ];
107 int p[2]; // synchronization pipe
114 int tun_fd = tun_alloc(IFF_TAP, if_name);
124 open("/dev/null", O_WRONLY);
126 send_fd(p[1], tun_fd, if_name);
130 if (read(p[0], &dummy, 1) != 1) {
131 ERROR("reading from the synch pipe");
133 printf("%s\n", if_name);