tools: first additions of userspace integration

This is designed to work with a server that follows this:

  struct sockaddr_un addr = {
      .sun_family = AF_UNIX,
      .sun_path = "/var/run/wireguard/wguserspace0.sock"
  };
  int fd, ret;
  ssize_t len;
  socklen_t socklen;
  struct wgdevice *device;

  fd = socket(AF_UNIX, SOCK_DGRAM, 0);
  if (fd < 0)
      exit(1);
  if (bind(fd, (struct sockaddr *)&addr, sizeof(addr)) < 0)
      exit(1);

  for (;;) {
      /* First we look at how big the next message is, so we know how much to
       * allocate. Note on BSD you can instead use ioctl(fd, FIONREAD, &len). */
      len = recv(fd, NULL, 0, MSG_PEEK | MSG_TRUNC);
      if (len < 0) {
          handle_error();
          continue;
      }
      /* Next we allocate a buffer for the received data. */
      device = NULL;
      if (len) {
          device = malloc(len);
          if (!device) {
              handle_error();
              continue;
          }
      }
      /* Finally we receive the data, storing too the return address. */
      socklen = sizeof(addr);
      len = recvfrom(fd, device, len, 0, (struct sockaddr *)&addr, (socklen_t *)&socklen);
      if (len < 0) {
          handle_error();
          free(device);
          continue;
      }
      if (!len) { /* If len is zero, it's a "get" request, so we send our device back. */
          device = get_current_wireguard_device(&len);
          sendto(fd, device, len, 0, (struct sockaddr *)&addr, socklen);
      } else { /* Otherwise, we just received a wgdevice, so we should "set" and send back the return status. */
          ret = set_current_wireguard_device(device);
          sendto(fd, &ret, sizeof(ret), 0, (struct sockaddr *)&addr, socklen);
          free(device);
      }
  }

1 files changed, 2 insertions, 2 deletions

diff --git a/src/tools/showconf.c b/src/tools/showconf.c
index 95d2e17..68084c0 100644
--- a/src/tools/showconf.c
+++ b/src/tools/showconf.c
@@ -31,13 +31,13 @@ int showconf_main(int argc, char *argv[])
 		return 1;
 	}
 
-	if (!kernel_has_wireguard_interface(argv[1])) {
+	if (!has_wireguard_interface(argv[1])) {
 		fprintf(stderr, "`%s` is not a valid WireGuard interface\n", argv[1]);
 		fprintf(stderr, "Usage: %s %s <interface>\n", PROG_NAME, argv[0]);
 		return 1;
 	}
 
-	if (kernel_get_device(&device, argv[1])) {
+	if (get_device(&device, argv[1])) {
 		perror("Unable to get device");
 		goto cleanup;
 	}