int unix_listen_opts(QemuOpts *opts) { struct sockaddr_un un; const char *path = qemu_opt_get(opts, "path"); int sock, fd; sock = socket(PF_UNIX, SOCK_STREAM, 0); if (sock < 0) { perror("socket(unix)"); return -1; } memset(&un, 0, sizeof(un)); un.sun_family = AF_UNIX; if (path && strlen(path)) { snprintf(un.sun_path, sizeof(un.sun_path), "%s", path); } else { char *tmpdir = getenv("TMPDIR"); snprintf(un.sun_path, sizeof(un.sun_path), "%s/qemu-socket-XXXXXX", tmpdir ? tmpdir : "/tmp"); /* * This dummy fd usage silences the mktemp() unsecure warning. * Using mkstemp() doesn't make things more secure here * though. bind() complains about existing files, so we have * to unlink first and thus re-open the race window. The * worst case possible is bind() failing, i.e. a DoS attack. */ fd = mkstemp(un.sun_path); close(fd); qemu_opt_set(opts, "path", un.sun_path); } unlink(un.sun_path); if (bind(sock, (struct sockaddr*) &un, sizeof(un)) < 0) { fprintf(stderr, "bind(unix:%s): %s\n", un.sun_path, strerror(errno)); goto err; } if (listen(sock, 1) < 0) { fprintf(stderr, "listen(unix:%s): %s\n", un.sun_path, strerror(errno)); goto err; } if (sockets_debug) fprintf(stderr, "bind(unix:%s): OK\n", un.sun_path); return sock; err: closesocket(sock); return -1; }