Merge tag 'u-boot-dfu-20240419' of https://source.denx.de/u-boot/custodians/u-boot-dfu

u-boot-dfu-20240419

- new "fastboot oem board" command

doc/android/fastboot.rst

@@ -30,6 +30,7 @@ The following OEM commands are supported (if enabled):
 - ``oem bootbus``  - this executes ``mmc bootbus %x %s`` to configure eMMC
 - ``oem run`` - this executes an arbitrary U-Boot command
 - ``oem console`` - this dumps U-Boot console record buffer
+- ``oem board`` - this executes a custom board function which is defined by the vendor
 
 Support for both eMMC and NAND devices is included.
 
@@ -246,6 +247,23 @@ including multiple commands (using e.g. ``;`` or ``&&``) and control structures
 (``if``, ``while``, etc.). The exit code of ``fastboot`` will reflect the exit
 code of the command you ran.
 
+Running Custom Vendor Code
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+U-Boot allows you to execute custom fastboot logic, which can be defined
+in board/ files. It can still be used for production devices with verified
+boot, because the vendor defines logic at compile time by implementing
+fastboot_oem_board() function. The attacker will not be able to execute
+custom commands / code. For example, this can be useful for custom flashing
+or erasing protocols::
+
+    $ fastboot stage bootloader.img
+    $ fastboot oem board:write_bootloader
+
+In this case, ``cmd_parameter`` argument of the function ``fastboot_oem_board()``
+will contain string "write_bootloader" and ``data`` argument is a pointer to
+fastboot input buffer, which contains the contents of bootloader.img file.
+
 References
 ----------
 

drivers/fastboot/Kconfig

@@ -253,6 +253,13 @@ config FASTBOOT_CMD_OEM_CONSOLE
 	  Add support for the "oem console" command to input and read console
 	  record buffer.
 
+config FASTBOOT_OEM_BOARD
+	bool "Enable the 'oem board' command"
+	help
+	  This extends the fastboot protocol with an "oem board" command. This
+	  command allows running vendor custom code defined in board/ files.
+	  Otherwise, it will do nothing and send fastboot fail.
+
 endif # FASTBOOT
 
 endmenu

drivers/fastboot/fb_command.c

@@ -42,6 +42,7 @@ static void oem_format(char *, char *);
 static void oem_partconf(char *, char *);
 static void oem_bootbus(char *, char *);
 static void oem_console(char *, char *);
+static void oem_board(char *, char *);
 static void run_ucmd(char *, char *);
 static void run_acmd(char *, char *);
 
@@ -113,6 +114,10 @@ static const struct {
 		.command = "oem console",
 		.dispatch = CONFIG_IS_ENABLED(FASTBOOT_CMD_OEM_CONSOLE, (oem_console), (NULL))
 	},
+	[FASTBOOT_COMMAND_OEM_BOARD] = {
+		.command = "oem board",
+		.dispatch = CONFIG_IS_ENABLED(FASTBOOT_OEM_BOARD, (oem_board), (NULL))
+	},
 	[FASTBOOT_COMMAND_UCMD] = {
 		.command = "UCmd",
 		.dispatch = CONFIG_IS_ENABLED(FASTBOOT_UUU_SUPPORT, (run_ucmd), (NULL))
@@ -542,3 +547,28 @@ static void __maybe_unused oem_console(char *cmd_parameter, char *response)
 	else
 		fastboot_response(FASTBOOT_MULTIRESPONSE_START, response, NULL);
 }
+
+/**
+ * fastboot_oem_board() - Execute the OEM board command. This is default
+ * weak implementation, which may be overwritten in board/ files.
+ *
+ * @cmd_parameter: Pointer to command parameter
+ * @data: Pointer to fastboot input buffer
+ * @size: Size of the fastboot input buffer
+ * @response: Pointer to fastboot response buffer
+ */
+void __weak fastboot_oem_board(char *cmd_parameter, void *data, u32 size, char *response)
+{
+	fastboot_fail("oem board function not defined", response);
+}
+
+/**
+ * oem_board() - Execute the OEM board command
+ *
+ * @cmd_parameter: Pointer to command parameter
+ * @response: Pointer to fastboot response buffer
+ */
+static void __maybe_unused oem_board(char *cmd_parameter, char *response)
+{
+	fastboot_oem_board(cmd_parameter, (void *)fastboot_buf_addr, image_size, response);
+}

include/fastboot.h

@@ -48,6 +48,7 @@ enum {
 	FASTBOOT_COMMAND_OEM_BOOTBUS,
 	FASTBOOT_COMMAND_OEM_RUN,
 	FASTBOOT_COMMAND_OEM_CONSOLE,
+	FASTBOOT_COMMAND_OEM_BOARD,
 	FASTBOOT_COMMAND_ACMD,
 	FASTBOOT_COMMAND_UCMD,
 	FASTBOOT_COMMAND_COUNT