[U-Boot] [PATCH v2 2/3] x86: baytrail: Add fsp-header verification for secure boot fsp

[Bin Meng <bmeng.cn@gmail.com>]

Hi Anatolij,

On Tue, May 16, 2017 at 3:55 PM, Anatolij Gustschin <agust@denx.de> wrote:
> From: Markus Valentin <mv@denx.de>
>
> Introduce a new Kconfig variable for secure boot on baytrail based
> platforms. If this variable is set the build process tries to use
> fsp-sb.bin instead of fsp.bin (-sb is the secure boot enabled fsp).
>
> Also check the two fsp headers against each other and print if secure
> boot is enabled or not.
>
> Signed-off-by: Markus Valentin <mv@denx.de>
> Signed-off-by: Anatolij Gustschin <agust@denx.de>
> ---
> Changes in v2:
>  - use if (IS_ENABLED(CONFIG_*)) instead of #ifdef
>  - s/SB/Secure Boot/
>  - minor Kconfig help cleanup
>
>  arch/x86/Kconfig                       | 13 ++++++++++++-
>  arch/x86/include/asm/fsp/fsp_support.h |  2 ++
>  arch/x86/lib/fsp/fsp_support.c         | 18 ++++++++++++++++++
>  3 files changed, 32 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 9ead3eb..8cea393 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -348,7 +348,8 @@ config HAVE_FSP
>  config FSP_FILE
>         string "Firmware Support Package binary filename"
>         depends on HAVE_FSP
> -       default "fsp.bin"
> +       default "fsp.bin" if !BAYTRAIL_SECURE_BOOT
> +       default "fsp-sb.bin" if BAYTRAIL_SECURE_BOOT
>         help
>           The filename of the file to use as Firmware Support Package binary
>           in the board directory.
> @@ -400,6 +401,16 @@ config FSP_BROKEN_HOB
>           do not overwrite the important boot service data which is used by
>           FSP, otherwise the subsequent call to fsp_notify() will fail.
>
> +config BAYTRAIL_SECURE_BOOT

Should this be in arch/x86/cpu/baytrail/Kconfig instead?

> +       bool "Enable Secure Boot on BayTrail"
> +       depends on HAVE_FSP
> +       default n
> +       help
> +         Use the SecureBoot Features of the BayTrail platform. This switch

nits: secure boot feature

> +         enables the usage of the secure-boot enabled fsp.bin (fsp-sb.bin)
> +         for your board you need to provide this yourself. You can reconfigure
> +         your fsp with the Intel BCT tool to enable SecureBoot.

nits: secure boot

> +
>  config ENABLE_MRC_CACHE
>         bool "Enable MRC cache"
>         depends on !EFI && !SYS_COREBOOT
> diff --git a/arch/x86/include/asm/fsp/fsp_support.h b/arch/x86/include/asm/fsp/fsp_support.h
> index 61d811f..bae17bc 100644
> --- a/arch/x86/include/asm/fsp/fsp_support.h
> +++ b/arch/x86/include/asm/fsp/fsp_support.h
> @@ -21,6 +21,8 @@
>  #define FSP_LOWMEM_BASE                0x100000UL
>  #define FSP_HIGHMEM_BASE       0x100000000ULL
>  #define UPD_TERMINATOR         0x55AA
> +#define FSP_FIRST_HEADER_OFFSET                0x94
> +#define FSP_SECOND_HEADER_OFFSET       0x20494

Are these two offsets common to all FSP, or BayTrail-specific values?

>
>
>  /**
> diff --git a/arch/x86/lib/fsp/fsp_support.c b/arch/x86/lib/fsp/fsp_support.c
> index a480361..0bbd9ae 100644
> --- a/arch/x86/lib/fsp/fsp_support.c
> +++ b/arch/x86/lib/fsp/fsp_support.c
> @@ -120,6 +120,14 @@ void fsp_init(u32 stack_top, u32 boot_mode, void *nvs_buf)
>                 panic("Invalid FSP header");
>         }
>
> +       if (IS_ENABLED(CONFIG_BAYTRAIL_SECURE_BOOT)) {
> +               /* compare primary and secondary header */
> +               if (memcmp((void *)(CONFIG_FSP_ADDR + FSP_FIRST_HEADER_OFFSET),
> +                          (void *)(CONFIG_FSP_ADDR + FSP_SECOND_HEADER_OFFSET),
> +                          fsp_hdr->hdr_len))
> +                       panic("Secure Boot: 1st & 2nd FSP headers don't match");
> +       }
> +
>         config_data.common.fsp_hdr = fsp_hdr;
>         config_data.common.stack_top = stack_top;
>         config_data.common.boot_mode = boot_mode;
> @@ -134,6 +142,16 @@ void fsp_init(u32 stack_top, u32 boot_mode, void *nvs_buf)
>
>         fsp_upd = &config_data.fsp_upd;
>
> +       if (IS_ENABLED(CONFIG_BAYTRAIL_SECURE_BOOT)) {
> +               /*
> +                * if the enable secure boot flag is not 1, secure boot has not
> +                * been activated in the FSP which results in the TXE-Engine not
> +                * getting loaded
> +                */
> +               printf("FSP: Secure Boot %sabled\n",
> +                      fsp_vpd->enable_secure_boot == 1 ? "en" : "dis");

I believe this won't build for other FSP platforms due to no
enable_secure_boot member in fsp_vpd structure.

> +       }
> +
>         /* Copy default data from Flash */
>         memcpy(fsp_upd, (void *)(fsp_hdr->img_base + fsp_vpd->upd_offset),
>                sizeof(struct upd_region));
> --

Regards,
Bin