Hi Alexey,
On 4/8/24 12:15, Alexey Romanov wrote:
Currently, fastboot protocol in U-Boot has no opportunity to execute vendor custom code with verifed boot. This patch introduce new fastboot subcommand fastboot oem board:<cmd>, which allow to run custom oem_board function.
Default implementation is __weak. Vendor must redefine it in board/ folder with his own logic.
For example, some vendors have their custom nand/emmc partition flashing or erasing. Here some typical command for such use cases:
flashing:
$ fastboot stage bootloader.img $ fastboot oem board:write_bootloader
erasing:
$ fastboot oem board:erase_env
Signed-off-by: Alexey Romanov avromanov@salutedevices.com
doc/android/fastboot.rst | 18 ++++++++++++++++++ drivers/fastboot/Kconfig | 7 +++++++ drivers/fastboot/fb_command.c | 30 ++++++++++++++++++++++++++++++ include/fastboot.h | 1 + 4 files changed, 56 insertions(+)
diff --git a/doc/android/fastboot.rst b/doc/android/fastboot.rst index 05d8f77759..2020590657 100644 --- a/doc/android/fastboot.rst +++ b/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 an custom board function which is defined by vendor
s/an/a/
+the vendor? (missing "the")
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 vendor define logic at compile time by overriding weak
s/vendor define/the vendor defines/
Suggestion:
Replace "by overriding weak implementation of fastboot_oem_board()" with "by implementing fastboot_oem_board()", the weak symbol is an implementation detail I don't think we need to keep in the documentation?
+implementation of fastboot_oem_board() function. The attacker will +not able to execute his commands / code. For example, this can be useful
+be able (missing be)
s/his/custom/ or s/his/their/
+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 containing the contents of bootloader.img file.
Either
-which (remove "which")
s/which containing/which contains/
Cheers, Quentin