" -t, --persistent don't exit on the last connection\n"
" -v, --verbose display extra debugging information\n"
" -x, --export-name=NAME expose export by name\n"
+" -D, --description=TEXT with -x, also export a human-readable description\n"
"\n"
"Exposing part of the image:\n"
" -o, --offset=OFFSET offset into the image\n"
return creds;
}
+static void setup_address_and_port(const char **address, const char **port)
+{
+ if (*address == NULL) {
+ *address = "0.0.0.0";
+ }
+
+ if (*port == NULL) {
+ *port = stringify(NBD_DEFAULT_PORT);
+ }
+}
+
+#define FIRST_SOCKET_ACTIVATION_FD 3 /* defined by systemd ABI */
+
+#ifndef _WIN32
+/*
+ * Check if socket activation was requested via use of the
+ * LISTEN_FDS and LISTEN_PID environment variables.
+ *
+ * Returns 0 if no socket activation, or the number of FDs.
+ */
+static unsigned int check_socket_activation(void)
+{
+ const char *s;
+ unsigned long pid;
+ unsigned long nr_fds;
+ unsigned int i;
+ int fd;
+ int err;
+
+ s = getenv("LISTEN_PID");
+ if (s == NULL) {
+ return 0;
+ }
+ err = qemu_strtoul(s, NULL, 10, &pid);
+ if (err) {
+ if (verbose) {
+ fprintf(stderr, "malformed %s environment variable (ignored)\n",
+ "LISTEN_PID");
+ }
+ return 0;
+ }
+ if (pid != getpid()) {
+ if (verbose) {
+ fprintf(stderr, "%s was not for us (ignored)\n",
+ "LISTEN_PID");
+ }
+ return 0;
+ }
+
+ s = getenv("LISTEN_FDS");
+ if (s == NULL) {
+ return 0;
+ }
+ err = qemu_strtoul(s, NULL, 10, &nr_fds);
+ if (err) {
+ if (verbose) {
+ fprintf(stderr, "malformed %s environment variable (ignored)\n",
+ "LISTEN_FDS");
+ }
+ return 0;
+ }
+ assert(nr_fds <= UINT_MAX);
+
+ /* A limitation of current qemu-nbd is that it can only listen on
+ * a single socket. When that limitation is lifted, we can change
+ * this function to allow LISTEN_FDS > 1, and remove the assertion
+ * in the main function below.
+ */
+ if (nr_fds > 1) {
+ error_report("qemu-nbd does not support socket activation with %s > 1",
+ "LISTEN_FDS");
+ exit(EXIT_FAILURE);
+ }
+
+ /* So these are not passed to any child processes we might start. */
+ unsetenv("LISTEN_FDS");
+ unsetenv("LISTEN_PID");
+
+ /* So the file descriptors don't leak into child processes. */
+ for (i = 0; i < nr_fds; ++i) {
+ fd = FIRST_SOCKET_ACTIVATION_FD + i;
+ if (fcntl(fd, F_SETFD, FD_CLOEXEC) == -1) {
+ /* If we cannot set FD_CLOEXEC then it probably means the file
+ * descriptor is invalid, so socket activation has gone wrong
+ * and we should exit.
+ */
+ error_report("Socket activation failed: "
+ "invalid file descriptor fd = %d: %m",
+ fd);
+ exit(EXIT_FAILURE);
+ }
+ }
+
+ return (unsigned int) nr_fds;
+}
+
+#else /* !_WIN32 */
+static unsigned int check_socket_activation(void)
+{
+ return 0;
+}
+#endif
+
+/*
+ * Check socket parameters compatibility when socket activation is used.
+ */
+static const char *socket_activation_validate_opts(const char *device,
+ const char *sockpath,
+ const char *address,
+ const char *port)
+{
+ if (device != NULL) {
+ return "NBD device can't be set when using socket activation";
+ }
+
+ if (sockpath != NULL) {
+ return "Unix socket can't be set when using socket activation";
+ }
+
+ if (address != NULL) {
+ return "The interface can't be set when using socket activation";
+ }
+
+ if (port != NULL) {
+ return "TCP port number can't be set when using socket activation";
+ }
+
+ return NULL;
+}
int main(int argc, char **argv)
{
off_t dev_offset = 0;
uint16_t nbdflags = 0;
bool disconnect = false;
- const char *bindto = "0.0.0.0";
+ const char *bindto = NULL;
const char *port = NULL;
char *sockpath = NULL;
char *device = NULL;
off_t fd_size;
QemuOpts *sn_opts = NULL;
const char *sn_id_or_name = NULL;
- const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:";
+ const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:";
struct option lopt[] = {
{ "help", no_argument, NULL, 'h' },
{ "version", no_argument, NULL, 'V' },
{ "verbose", no_argument, NULL, 'v' },
{ "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT },
{ "export-name", required_argument, NULL, 'x' },
+ { "description", required_argument, NULL, 'D' },
{ "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS },
{ "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS },
{ "trace", required_argument, NULL, 'T' },
BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
QDict *options = NULL;
const char *export_name = NULL;
+ const char *export_description = NULL;
const char *tlscredsid = NULL;
bool imageOpts = false;
bool writethrough = true;
char *trace_file = NULL;
bool fork_process = false;
int old_stderr = -1;
+ unsigned socket_activation;
/* The client thread uses SIGTERM to interrupt the server. A signal
* handler ensures that "qemu-nbd -v -c" exits with a nice status code.
case 'x':
export_name = optarg;
break;
+ case 'D':
+ export_description = optarg;
+ break;
case 'v':
verbose = 1;
break;
trace_init_file(trace_file);
qemu_set_log(LOG_TRACE);
+ socket_activation = check_socket_activation();
+ if (socket_activation == 0) {
+ setup_address_and_port(&bindto, &port);
+ } else {
+ /* Using socket activation - check user didn't use -p etc. */
+ const char *err_msg = socket_activation_validate_opts(device, sockpath,
+ bindto, port);
+ if (err_msg != NULL) {
+ error_report("%s", err_msg);
+ exit(EXIT_FAILURE);
+ }
+ }
+
if (tlscredsid) {
if (sockpath) {
error_report("TLS is only supported with IPv4/IPv6");
snprintf(sockpath, 128, SOCKET_PATH, basename(device));
}
- saddr = nbd_build_socket_address(sockpath, bindto, port);
+ if (socket_activation == 0) {
+ server_ioc = qio_channel_socket_new();
+ saddr = nbd_build_socket_address(sockpath, bindto, port);
+ if (qio_channel_socket_listen_sync(server_ioc, saddr, &local_err) < 0) {
+ object_unref(OBJECT(server_ioc));
+ error_report_err(local_err);
+ return 1;
+ }
+ } else {
+ /* See comment in check_socket_activation above. */
+ assert(socket_activation == 1);
+ server_ioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD,
+ &local_err);
+ if (server_ioc == NULL) {
+ error_report("Failed to use socket activation: %s",
+ error_get_pretty(local_err));
+ exit(EXIT_FAILURE);
+ }
+ }
if (qemu_init_main_loop(&local_err)) {
error_report_err(local_err);
}
if (export_name) {
nbd_export_set_name(exp, export_name);
+ nbd_export_set_description(exp, export_description);
newproto = true;
- }
-
- server_ioc = qio_channel_socket_new();
- if (qio_channel_socket_listen_sync(server_ioc, saddr, &local_err) < 0) {
- object_unref(OBJECT(server_ioc));
- error_report_err(local_err);
- return 1;
+ } else if (export_description) {
+ error_report("Export description requires an export name");
+ exit(EXIT_FAILURE);
}
if (device) {