[PATCH 2/2] cmd: Add CONFIG_FIT_SIGNATURE_STRICT

[Igor Opaniuk]

Hi Oleksandr,

On Thu, Sep 16, 2021 at 4:10 PM Oleksandr Suvorov
<oleksandr.suvorov at foundries.io> wrote:
>
> From: Ricardo Salveti <ricardo at foundries.io>
>
> Add CONFIG_FIT_SIGNATURE_STRICT to require a valid FIT configuration
> signature for each command that is able to manipulate FIT images.
>
> Signed-off-by: Ricardo Salveti <ricardo at foundries.io>
> Co-developed-by: Oleksandr Suvorov <oleksandr.suvorov at foundries.io>
> Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov at foundries.io>
> ---
>
>  cmd/fpga.c          | 14 ++++++++++++++
>  cmd/source.c        | 14 ++++++++++++++
>  cmd/ximg.c          | 14 ++++++++++++++
>  common/Kconfig.boot |  4 ++++
>  4 files changed, 46 insertions(+)
>
> diff --git a/cmd/fpga.c b/cmd/fpga.c
> index 3fdd0b35e80..16d329590fa 100644
> --- a/cmd/fpga.c
> +++ b/cmd/fpga.c
> @@ -335,6 +335,20 @@ static int do_fpga_loadmk(struct cmd_tbl *cmdtp, int flag, int argc,
>                         return CMD_RET_FAILURE;
>                 }
>
> +               if (CONFIG_IS_ENABLED(FIT_SIGNATURE_STRICT)) {
> +                       /* validate required fit config entry */
> +                       noffset = fit_conf_get_node(fit_hdr, NULL);
> +                       if (noffset >= 0) {
> +                               if (fit_config_verify(fit_hdr, noffset)) {
> +                                       puts("Cannot verify FIT config node\n");
> +                                       return CMD_RET_FAILURE;
> +                               }
> +                       } else {
> +                               puts("FIT_SIGNATURE_STRICT requires a config node\n");
> +                               return CMD_RET_FAILURE;
> +                       }
> +               }
> +
>                 /* get fpga component image node offset */
>                 noffset = fit_image_get_node(fit_hdr, fit_uname);
>                 if (noffset < 0) {
> diff --git a/cmd/source.c b/cmd/source.c
> index 81e015b64ef..b08406dfcbf 100644
> --- a/cmd/source.c
> +++ b/cmd/source.c
> @@ -112,6 +112,20 @@ int image_source_script(ulong addr, const char *fit_uname)
>                         return 1;
>                 }
>
> +               if (CONFIG_IS_ENABLED(FIT_SIGNATURE_STRICT)) {
> +                       /* validate required fit config entry */
> +                       noffset = fit_conf_get_node(fit_hdr, NULL);
> +                       if (noffset >= 0) {
> +                               if (fit_config_verify(fit_hdr, noffset)) {
> +                                       puts("Cannot verify FIT config node\n");
> +                                       return 1;
> +                               }
> +                       } else {
> +                               puts("FIT_SIGNATURE_STRICT requires a config node\n");
> +                               return 1;
> +                       }
> +               }
> +
>                 if (!fit_uname)
>                         fit_uname = get_default_image(fit_hdr);
>
> diff --git a/cmd/ximg.c b/cmd/ximg.c
> index 65ba41320a0..39fccd8179c 100644
> --- a/cmd/ximg.c
> +++ b/cmd/ximg.c
> @@ -141,6 +141,20 @@ do_imgextract(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
>                         return 1;
>                 }
>
> +               if (CONFIG_IS_ENABLED(FIT_SIGNATURE_STRICT)) {
> +                       /* validate required fit config entry */
> +                       noffset = fit_conf_get_node(fit_hdr, NULL);
> +                       if (noffset >= 0) {
> +                               if (fit_config_verify(fit_hdr, noffset)) {
> +                                       puts("Cannot verify FIT config node\n");
> +                                       return 1;
> +                               }
> +                       } else {
> +                               puts("FIT_SIGNATURE_STRICT requires a config node\n");
> +                               return 1;
> +                       }
> +               }
> +
>                 /* get subimage node offset */
>                 noffset = fit_image_get_node(fit_hdr, uname);
>                 if (noffset < 0) {
> diff --git a/common/Kconfig.boot b/common/Kconfig.boot
> index 6f95d009dfa..ca7d9a8d971 100644
> --- a/common/Kconfig.boot
> +++ b/common/Kconfig.boot
> @@ -77,6 +77,10 @@ config FIT_SIGNATURE_MAX_SIZE
>           device memory. Assure this size does not extend past expected storage
>           space.
>
> +config FIT_SIGNATURE_STRICT
> +       bool "Requires a valid FIT configuration signature for every image"
> +       select FIT_SIGNATURE
> +
>  config FIT_RSASSA_PSS
>         bool "Support rsassa-pss signature scheme of FIT image contents"
>         depends on FIT_SIGNATURE
> --
> 2.31.1
>

There is duplication of the same piece of code in 3 different files,
maybe you could rework
that and move to some common function?

-- 
Best regards - Freundliche Grüsse - Meilleures salutations

Igor Opaniuk
Embedded Software Engineer
T:  +380 938364067
E: igor.opaniuk at foundries.io
W: www.foundries.io