Re: [PATCH u-boot-marvell 04/13] tools: kwboot: Validate 4-byte image data checksum

Stefan Roese
2021-10-26T05:43:19Z

On 25.10.21 15:12, Marek Behún wrote:
> From: Pali Rohár <pali@kernel.org>
>
> Data part of the image contains 4-byte checksum. Validate it when
> processing the image.
>
> Signed-off-by: Pali Rohár <pali@kernel.org>
> [ refactored ]
> Signed-off-by: Marek Behún <marek.behun@nic.cz>

Reviewed-by: Stefan Roese <sr@denx.de>

Thanks,
Stefan

> ---
> tools/kwboot.c | 34 ++++++++++++++++++++++++++++++++++
> 1 file changed, 34 insertions(+)
>
> diff --git a/tools/kwboot.c b/tools/kwboot.c
> index 4e29317f10..bc44301535 100644
> --- a/tools/kwboot.c
> +++ b/tools/kwboot.c
> @@ -1251,6 +1251,37 @@ kwboot_hdr_csum8(const void *hdr)
> return csum;
> }
>
> +static uint32_t *
> +kwboot_img_csum32_ptr(void *img)
> +{
> + struct main_hdr_v1 *hdr = img;
> + uint32_t datasz;
> +
> + datasz = le32_to_cpu(hdr->blocksize) - sizeof(uint32_t);
> +
> + return img + le32_to_cpu(hdr->srcaddr) + datasz;
> +}
> +
> +static uint32_t
> +kwboot_img_csum32(const void *img)
> +{
> + const struct main_hdr_v1 *hdr = img;
> + uint32_t datasz, csum = 0;
> + const uint32_t *data;
> +
> + datasz = le32_to_cpu(hdr->blocksize) - sizeof(csum);
> + if (datasz % sizeof(uint32_t))
> + return 0;
> +
> + data = img + le32_to_cpu(hdr->srcaddr);
> + while (datasz > 0) {
> + csum += le32_to_cpu(*data++);
> + datasz -= 4;
> + }
> +
> + return cpu_to_le32(csum);
> +}
> +
> static int
> kwboot_img_is_secure(void *img)
> {
> @@ -1462,6 +1493,9 @@ kwboot_img_patch(void *img, size_t *size, int baudrate)
> *size < le32_to_cpu(hdr->srcaddr) + le32_to_cpu(hdr->blocksize))
> goto err;
>
> + if (kwboot_img_csum32(img) != *kwboot_img_csum32_ptr(img))
> + goto err;
> +
> is_secure = kwboot_img_is_secure(img);
>
> if (hdr->blockid != IBR_HDR_UART_ID) {
>

Viele Grüße,
Stefan

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