1 files changed, 94 insertions, 0 deletions

diff --git a/sys/boot/efi/loader/main.c b/sys/boot/efi/loader/main.c
index 043306f691393..6fab757be5f1e 100644
--- a/sys/boot/efi/loader/main.c
+++ b/sys/boot/efi/loader/main.c
@@ -795,6 +795,100 @@ command_fdt(int argc, char *argv[])
 COMMAND_SET(fdt, "fdt", "flattened device tree handling", command_fdt);
 #endif
 
+/*
+ * Chain load another efi loader.
+ */
+static int
+command_chain(int argc, char *argv[])
+{
+	EFI_GUID LoadedImageGUID = LOADED_IMAGE_PROTOCOL;
+	EFI_HANDLE loaderhandle;
+	EFI_LOADED_IMAGE *loaded_image;
+	EFI_STATUS status;
+	struct stat st;
+	struct devdesc *dev;
+	char *name, *path;
+	void *buf;
+	int fd;
+
+	if (argc < 2) {
+		command_errmsg = "wrong number of arguments";
+		return (CMD_ERROR);
+	}
+
+	name = argv[1];
+
+	if ((fd = open(name, O_RDONLY)) < 0) {
+		command_errmsg = "no such file";
+		return (CMD_ERROR);
+	}
+
+	if (fstat(fd, &st) < -1) {
+		command_errmsg = "stat failed";
+		close(fd);
+		return (CMD_ERROR);
+	}
+
+	status = BS->AllocatePool(EfiLoaderCode, (UINTN)st.st_size, &buf);
+	if (status != EFI_SUCCESS) {
+		command_errmsg = "failed to allocate buffer";
+		close(fd);
+		return (CMD_ERROR);
+	}
+	if (read(fd, buf, st.st_size) != st.st_size) {
+		command_errmsg = "error while reading the file";
+		(void)BS->FreePool(buf);
+		close(fd);
+		return (CMD_ERROR);
+	}
+	close(fd);
+	status = BS->LoadImage(FALSE, IH, NULL, buf, st.st_size, &loaderhandle);
+	(void)BS->FreePool(buf);
+	if (status != EFI_SUCCESS) {
+		command_errmsg = "LoadImage failed";
+		return (CMD_ERROR);
+	}
+	status = BS->HandleProtocol(loaderhandle, &LoadedImageGUID,
+	    (void **)&loaded_image);
+
+	if (argc > 2) {
+		int i, len = 0;
+		CHAR16 *argp;
+
+		for (i = 2; i < argc; i++)
+			len += strlen(argv[i]) + 1;
+
+		len *= sizeof (*argp);
+		loaded_image->LoadOptions = argp = malloc (len);
+		loaded_image->LoadOptionsSize = len;
+		for (i = 2; i < argc; i++) {
+			char *ptr = argv[i];
+			while (*ptr)
+				*(argp++) = *(ptr++);
+			*(argp++) = ' ';
+		}
+		*(--argv) = 0;
+	}
+
+	if (efi_getdev((void **)&dev, name, (const char **)&path) == 0)
+		loaded_image->DeviceHandle =
+		    efi_find_handle(dev->d_dev, dev->d_unit);
+
+	dev_cleanup();
+	status = BS->StartImage(loaderhandle, NULL, NULL);
+	if (status != EFI_SUCCESS) {
+		command_errmsg = "StartImage failed";
+		free(loaded_image->LoadOptions);
+		loaded_image->LoadOptions = NULL;
+		status = BS->UnloadImage(loaded_image);
+		return (CMD_ERROR);
+	}
+
+	return (CMD_ERROR);	/* not reached */
+}
+
+COMMAND_SET(chain, "chain", "chain load file", command_chain);
+
 #ifdef EFI_ZFS_BOOT
 static void
 efi_zfs_probe(void)