[U-Boot] [PATCH v3 03/16] rockchip: mkimage: Allow encoding of loader code in spl images

[Kever Yang <kever.yang@rock-chips.com>]

Hi Heiko,

On 02/04/2017 12:09 AM, Heiko Stuebner wrote:
> Rockchip SoCs allow the spl code to be rc4-encoded, not only the
> image header, but only newer SoCs allow this encoding to be disabled.
>
> The rk3188 is not part of those and requires its boot code to be
> rc4-encoded with the regular key. So add the ability to do this
> encoding via a setting on a per-soc basis when building spl images.
>
> Signed-off-by: Heiko Stuebner <heiko@sntech.de>
> ---
>   tools/rkcommon.c | 33 +++++++++++++++++++++++++++++----
>   tools/rkcommon.h | 22 ++++++++++++++++++++++
>   tools/rkimage.c  |  3 +++
>   tools/rksd.c     |  4 ++++
>   tools/rkspi.c    |  4 ++++
>   5 files changed, 62 insertions(+), 4 deletions(-)
>
> diff --git a/tools/rkcommon.c b/tools/rkcommon.c
> index 0a072aa83c..ed9b24137a 100644
> --- a/tools/rkcommon.c
> +++ b/tools/rkcommon.c
> @@ -46,17 +46,19 @@ struct header0_info {
>    * @imagename:		Image name(passed by "mkimage -n")
>    * @spl_hdr:		Boot ROM requires a 4-bytes spl header
>    * @spl_size:		Spl size(include extra 4-bytes spl header)
> + * @spl_rc4:		RC4 encode the SPL binary (same key as header)
>    */
>   struct spl_info {
>   	const char *imagename;
>   	const char *spl_hdr;
>   	const uint32_t spl_size;
> +	const bool spl_rc4;
>   };
>   
>   static struct spl_info spl_infos[] = {
> -	{ "rk3036", "RK30", 0x1000 },
> -	{ "rk3288", "RK32", 0x8000 },
> -	{ "rk3399", "RK33", 0x20000 },
> +	{ "rk3036", "RK30", 0x1000, false },
> +	{ "rk3288", "RK32", 0x8000, false },
> +	{ "rk3399", "RK33", 0x20000, false },
>   };
>   
>   static unsigned char rc4_key[16] = {
> @@ -113,6 +115,16 @@ int rkcommon_get_spl_size(struct image_tool_params *params)
>   	return info->spl_size;
>   }
>   
> +bool rkcommon_need_rc4_spl(struct image_tool_params *params)
> +{
> +	struct spl_info *info = rkcommon_get_spl_info(params->imagename);
> +
> +	/*
> +	 * info would not be NULL, because of we checked params before.
> +	 */
> +	return info->spl_rc4;
> +}
> +
>   int rkcommon_set_header(void *buf, uint file_size,
>   			struct image_tool_params *params)
>   {
> @@ -124,7 +136,7 @@ int rkcommon_set_header(void *buf, uint file_size,
>   	memset(buf,  '\0', RK_INIT_OFFSET * RK_BLK_SIZE);
>   	hdr = (struct header0_info *)buf;
>   	hdr->signature = RK_SIGNATURE;
> -	hdr->disable_rc4 = 1;
> +	hdr->disable_rc4 = !rkcommon_need_rc4_spl(params);
>   	hdr->init_offset = RK_INIT_OFFSET;
>   
>   	hdr->init_size = (file_size + RK_BLK_SIZE - 1) / RK_BLK_SIZE;
> @@ -135,3 +147,16 @@ int rkcommon_set_header(void *buf, uint file_size,
>   
>   	return 0;
>   }
> +
> +void rkcommon_rc4_encode_spl(void *buf, unsigned int offset, unsigned int size)
> +{
> +	unsigned int remaining = size;
> +
> +	while (remaining > 0) {
> +		int step = (remaining > RK_BLK_SIZE) ? RK_BLK_SIZE : remaining;
> +
> +		rc4_encode(buf + offset, step, rc4_key);
> +		offset += RK_BLK_SIZE;
> +		remaining -= step;
> +	}
> +}
> diff --git a/tools/rkcommon.h b/tools/rkcommon.h
> index c69540f5f3..b4f6f327dc 100644
> --- a/tools/rkcommon.h
> +++ b/tools/rkcommon.h
> @@ -55,4 +55,26 @@ int rkcommon_get_spl_size(struct image_tool_params *params);
>   int rkcommon_set_header(void *buf, uint file_size,
>   			struct image_tool_params *params);
>   
> +/**
> + * rkcommon_need_rc4_spl() - check if rc4 encoded spl is required
> + *
> + * Some socs cannot disable the rc4-encryption of the spl binary.
> + * rc4 encryption is disabled normally except on socs that cannot
> + * handle unencrypted binaries.
> + * @return true or false depending on rc4 being required.
> + */
> +bool rkcommon_need_rc4_spl(struct image_tool_params *params);
> +
> +/**
> + * rkcommon_rc4_encode_spl() - encode the spl binary
> + *
> + * Encrypts the SPL binary using the generic rc4 key as required
> + * by some socs.
> + *
> + * @buf:	Pointer to the SPL data (header and SPL binary)
> + * @offset:	offset inside buf to start at
> + * @size:	number of bytes to encode
> + */
> +void rkcommon_rc4_encode_spl(void *buf, unsigned int offset, unsigned int size);
> +
>   #endif
> diff --git a/tools/rkimage.c b/tools/rkimage.c
> index ef31cb6944..44d098c775 100644
> --- a/tools/rkimage.c
> +++ b/tools/rkimage.c
> @@ -28,6 +28,9 @@ static void rkimage_set_header(void *buf, struct stat *sbuf, int ifd,
>   {
>   	memcpy(buf + RK_SPL_HDR_START, rkcommon_get_spl_hdr(params),
>   	       RK_SPL_HDR_SIZE);
> +
> +	if (rkcommon_need_rc4_spl(params))
> +		rkcommon_rc4_encode_spl(buf, 4, params->file_size);
>   }
>   
>   static int rkimage_extract_subimage(void *buf, struct image_tool_params *params)
> diff --git a/tools/rksd.c b/tools/rksd.c
> index a2baa74d31..ff2233ff2d 100644
> --- a/tools/rksd.c
> +++ b/tools/rksd.c
> @@ -41,6 +41,10 @@ static void rksd_set_header(void *buf,  struct stat *sbuf,  int ifd,
>   
>   	memcpy(buf + RK_SPL_HDR_START, rkcommon_get_spl_hdr(params),
>   	       RK_SPL_HDR_SIZE);
> +
> +	if (rkcommon_need_rc4_spl(params))
> +		rkcommon_rc4_encode_spl(buf, RK_SPL_START - 4,
> +					params->file_size - RK_SPL_START + 4);
>   }
>   
>   static int rksd_extract_subimage(void *buf,  struct image_tool_params *params)
> diff --git a/tools/rkspi.c b/tools/rkspi.c
> index a0b0051d38..0271d2e817 100644
> --- a/tools/rkspi.c
> +++ b/tools/rkspi.c
> @@ -48,6 +48,10 @@ static void rkspi_set_header(void *buf, struct stat *sbuf, int ifd,
>   	memcpy(buf + RK_SPL_HDR_START, rkcommon_get_spl_hdr(params),
>   	       RK_SPL_HDR_SIZE);
>   
> +	if (rkcommon_need_rc4_spl(params))
> +		rkcommon_rc4_encode_spl(buf, RK_SPL_START - 4,
> +					params->file_size - RK_SPL_START + 4);
> +
>   	/*
>   	 * Spread the image out so we only use the first 2KB of each 4KB
>   	 * region. This is a feature of the SPI format required by the Rockchip

Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
Tested-by: Kever Yang <kever.yang@rock-chips.com>

Thanks,
- Kever