[PATCH u-boot-mvebu 09/31] tools: kwbimage: Validate data checksum of v1 images

[Stefan Roese]

On 08.07.21 19:30, Marek Behún wrote:
> From: Pali Rohár <pali at kernel.org>
> 
> The data part of v1 images contains 32-bit checksum after the data.
> Validate whether this checksum is correct.
> 
> Signed-off-by: Pali Rohár <pali at kernel.org>
> Reviewed-by: Marek Behún <marek.behun at nic.cz>

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

Thanks,
Stefan

> ---
>   tools/kwbimage.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 46 insertions(+)
> 
> diff --git a/tools/kwbimage.c b/tools/kwbimage.c
> index 5f7cb8376a..de6eb3f075 100644
> --- a/tools/kwbimage.c
> +++ b/tools/kwbimage.c
> @@ -1670,6 +1670,9 @@ static int kwbimage_verify_header(unsigned char *ptr, int image_size,
>   
>   	if (image_version((void *)ptr) == 1) {
>   		struct main_hdr_v1 *mhdr = (struct main_hdr_v1 *)ptr;
> +		unsigned char *endptr = ptr + sizeof(*mhdr);
> +		uint32_t offset;
> +		uint32_t size;
>   
>   		if (mhdr->ext & 0x1) {
>   			uint32_t ohdr_size;
> @@ -1693,7 +1696,50 @@ static int kwbimage_verify_header(unsigned char *ptr, int image_size,
>   				ohdr = (struct opt_hdr_v1 *)((uint8_t *)ohdr +
>   							     4 + ohdr_size + 4);
>   			}
> +
> +			endptr = ((uint8_t *)ohdr + 4 + ohdr_size + 4);
> +		}
> +
> +		offset = le32_to_cpu(mhdr->srcaddr);
> +
> +		/*
> +		 * For SATA srcaddr is specified in number of sectors.
> +		 * The main header is must be stored at sector number 1.
> +		 * This expects that sector size is 512 bytes and recalculates
> +		 * data offset to bytes relative to the main header.
> +		 */
> +		if (mhdr->blockid == IBR_HDR_SATA_ID) {
> +			if (offset < 1)
> +				return -FDT_ERR_BADSTRUCTURE;
> +			offset -= 1;
> +			offset *= 512;
>   		}
> +
> +		/*
> +		 * For SDIO srcaddr is specified in number of sectors.
> +		 * This expects that sector size is 512 bytes and recalculates
> +		 * data offset to bytes.
> +		 */
> +		if (mhdr->blockid == IBR_HDR_SDIO_ID)
> +			offset *= 512;
> +
> +		/*
> +		 * For PCIe srcaddr is always set to 0xFFFFFFFF.
> +		 * This expects that data starts after all headers.
> +		 */
> +		if (mhdr->blockid == IBR_HDR_PEX_ID && offset == 0xFFFFFFFF)
> +			offset = endptr - ptr;
> +
> +		if (offset > image_size || offset % 4 != 0)
> +			return -FDT_ERR_BADSTRUCTURE;
> +
> +		size = le32_to_cpu(mhdr->blocksize);
> +		if (offset + size > image_size || size % 4 != 0)
> +			return -FDT_ERR_BADSTRUCTURE;
> +
> +		if (image_checksum32(ptr + offset, size - 4) !=
> +		    *(uint32_t *)(ptr + offset + size - 4))
> +			return -FDT_ERR_BADSTRUCTURE;
>   	}
>   
>   	return 0;
> 


Viele Grüße,
Stefan

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