[U-Boot] [PATCH v2] imx: hab: extend hab_auth_img to calculate ivt_offset

[Breno Matheus Lima]

Hi Parthiban,

Em qua, 21 de nov de 2018 às 11:50, Parthiban Nallathambi <pn at denx.de> escreveu:
>
> Current implementation of hab_auth_img command needs ivt_offset to
> authenticate the image. But ivt header is placed at the end of image
> date after padding.
>
> This leaves the usage of hab_auth_img command to fixed size or static
> offset for ivt header. New function "get_image_ivt_offset" is introduced
> to find the ivt offset during runtime. The case conditional check in this
> function is same as boot_get_kernel in common/bootm.c
>
> With this variable length image e.g. FIT image with any random size can
> have IVT at the end and ivt_offset option can be left optional
>
> Can be used as "hab_auth_img $loadaddr $filesize" from u-boot script
>
> Signed-off-by: Parthiban Nallathambi <pn at denx.de>
> ---
>
> Notes:
>     Changelog in v2:
>     - Finding IVT offset doesn't need length. Removed the
>     length argument from get_image_ivt_offset
>
>  arch/arm/mach-imx/hab.c | 29 +++++++++++++++++++++++++++--
>  1 file changed, 27 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm/mach-imx/hab.c b/arch/arm/mach-imx/hab.c
> index b88acd13da..dbfd692fa3 100644
> --- a/arch/arm/mach-imx/hab.c
> +++ b/arch/arm/mach-imx/hab.c
> @@ -6,6 +6,8 @@
>  #include <common.h>
>  #include <config.h>
>  #include <fuse.h>
> +#include <mapmem.h>
> +#include <image.h>
>  #include <asm/io.h>
>  #include <asm/system.h>
>  #include <asm/arch/clock.h>
> @@ -302,18 +304,41 @@ static int do_hab_status(cmd_tbl_t *cmdtp, int flag, int argc,
>         return 0;
>  }
>
> +static ulong get_image_ivt_offset(ulong img_addr)
> +{
> +       const void *buf;
> +
> +       buf = map_sysmem(img_addr, 0);
> +       switch (genimg_get_format(buf)) {
> +#if defined(CONFIG_IMAGE_FORMAT_LEGACY)
> +       case IMAGE_FORMAT_LEGACY:
> +               return (image_get_image_size((image_header_t *)img_addr)
> +                       + 0x1000 - 1)  & ~(0x1000 - 1);
> +#endif
> +#if IMAGE_ENABLE_FIT
> +       case IMAGE_FORMAT_FIT:
> +               return (fit_get_size(buf) + 0x1000 - 1)  & ~(0x1000 - 1);
> +#endif
> +       default:
> +               return 0;
> +       }
> +}


Do you have more details about the image header I should use here?

I'm trying to get the IVT offset for my Kernel image based on NXP
4.9.11_2.0.0_GA Linux release loaded at 0x80800000:

=> fatload mmc 0:1 0x80800000 zImage
=> hab_auth_img 0x80800000 <Len not being used>

The zImage size in Header looks correct (0x00726690), but
get_image_ivt_offset() is returning 0x0

$ hexdump zImage | head
0000000 0000 e1a0 0000 e1a0 0000 e1a0 0000 e1a0
*
0000020 0003 ea00 2818 016f 0000 0000 6690 0072
0000030 0201 0403 9000 e10f 04f8 eb00 7001 e1a0
0000040 8002 e1a0 2000 e10f 0003 e312 0001 1a00

Seems that genimg_get_format() is returning 0x0.

Any ideias if I'm missing something?

> +
>  static int do_authenticate_image(cmd_tbl_t *cmdtp, int flag, int argc,
>                                  char * const argv[])
>  {
>         ulong   addr, length, ivt_offset;
>         int     rcode = 0;
>
> -       if (argc < 4)
> +       if (argc < 3)

I think we can also change here to argc < 2, the function
get_image_ivt_offset() only requires the img addr now.

>                 return CMD_RET_USAGE;
>
>         addr = simple_strtoul(argv[1], NULL, 16);
>         length = simple_strtoul(argv[2], NULL, 16);
> -       ivt_offset = simple_strtoul(argv[3], NULL, 16);
> +       if (argc == 3)

argc ==2