[PATCH v2 4/5] lib: sha256: Add support for hardware specific sha256_process

[Simon Glass]

Hi Loic,

On Wed, 1 Jun 2022 at 12:27, Loic Poulain <loic.poulain at linaro.org> wrote:
>
> Mark sha256_process as weak to allow hardware specific implementation.
> Add parameter for supporting multiple blocks processing.
>
> Signed-off-by: Loic Poulain <loic.poulain at linaro.org>
> ---
>  lib/sha256.c | 26 +++++++++++++++++++-------
>  1 file changed, 19 insertions(+), 7 deletions(-)
>
> diff --git a/lib/sha256.c b/lib/sha256.c
> index c1fe93d..50b0b51 100644
> --- a/lib/sha256.c
> +++ b/lib/sha256.c
> @@ -14,6 +14,8 @@
>  #include <watchdog.h>
>  #include <u-boot/sha256.h>
>
> +#include <linux/compiler_attributes.h>
> +
>  const uint8_t sha256_der_prefix[SHA256_DER_LEN] = {
>         0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86,
>         0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, 0x05,
> @@ -55,7 +57,7 @@ void sha256_starts(sha256_context * ctx)
>         ctx->state[7] = 0x5BE0CD19;
>  }
>
> -static void sha256_process(sha256_context *ctx, const uint8_t data[64])
> +static void sha256_process_one(sha256_context *ctx, const uint8_t data[64])
>  {
>         uint32_t temp1, temp2;
>         uint32_t W[64];
> @@ -186,6 +188,18 @@ static void sha256_process(sha256_context *ctx, const uint8_t data[64])
>         ctx->state[7] += H;
>  }
>
> +__weak void sha256_process(sha256_context *ctx, const unsigned char *data,
> +                          unsigned int blocks)
> +{
> +       if (!blocks)
> +               return;
> +
> +       while (blocks--) {
> +               sha256_process_one(ctx, data);
> +               data += 64;
> +       }
> +}
> +
>  void sha256_update(sha256_context *ctx, const uint8_t *input, uint32_t length)
>  {
>         uint32_t left, fill;
> @@ -204,17 +218,15 @@ void sha256_update(sha256_context *ctx, const uint8_t *input, uint32_t length)
>
>         if (left && length >= fill) {
>                 memcpy((void *) (ctx->buffer + left), (void *) input, fill);
> -               sha256_process(ctx, ctx->buffer);
> +               sha256_process(ctx, ctx->buffer, 1);
>                 length -= fill;
>                 input += fill;
>                 left = 0;
>         }
>
> -       while (length >= 64) {
> -               sha256_process(ctx, input);
> -               length -= 64;
> -               input += 64;
> -       }
> +       sha256_process(ctx, input, length / 64);
> +       input += length / 64 * 64;
> +       length = length % 64;
>
>         if (length)
>                 memcpy((void *) (ctx->buffer + left), (void *) input, length);
> --
> 2.7.4
>

I just came across this patch as it broke minnowmax.

This should be using driver model, not weak functions. Please can you
take a look?

Regards,
Simon