[PATCH 2/3] tpm: use more algorithms than sha256 on pcr_read

[Ilias Apalodimas]

Hi Ruchika, 

[...]
> -		  void *data, unsigned int *updates);
> +		  u32 algorithm, void *data, u32 digest_len,

This goes into a tpm_u16() call.  It doesn't break anything currently, but
shouldn't we define this as u16 ?

> +		  unsigned int *updates);
>  
>  /**
>   * Issue a TPM2_GetCapability command.  This implementation is limited
> diff --git a/lib/tpm-v2.c b/lib/tpm-v2.c
> index 235f8c20d4..9f86eab814 100644
> --- a/lib/tpm-v2.c
> +++ b/lib/tpm-v2.c
> @@ -254,7 +254,8 @@ u32 tpm2_nv_write_value(struct udevice *dev, u32 index, const void *data,
>  }
>  
>  u32 tpm2_pcr_read(struct udevice *dev, u32 idx, unsigned int idx_min_sz,
> -		  void *data, unsigned int *updates)
> +		  u32 algorithm, void *data, u32 digest_len,
> +		  unsigned int *updates)
>  {
>  	u8 idx_array_sz = max(idx_min_sz, DIV_ROUND_UP(idx, 8));
>  	u8 command_v2[COMMAND_BUFFER_SIZE] = {
> @@ -264,7 +265,7 @@ u32 tpm2_pcr_read(struct udevice *dev, u32 idx, unsigned int idx_min_sz,
>  
>  		/* TPML_PCR_SELECTION */
>  		tpm_u32(1),			/* Number of selections */
> -		tpm_u16(TPM2_ALG_SHA256),	/* Algorithm of the hash */
> +		tpm_u16(algorithm),		/* Algorithm of the hash */
>  		idx_array_sz,			/* Array size for selection */
>  		/* bitmap(idx)			   Selected PCR bitmap */
>  	};
> @@ -283,10 +284,13 @@ u32 tpm2_pcr_read(struct udevice *dev, u32 idx, unsigned int idx_min_sz,
>  	if (ret)
>  		return ret;
>  
> +	if (digest_len > response_len)
> +		return TPM_LIB_ERROR;
> +
>  	if (unpack_byte_string(response, response_len, "ds",
>  			       10, &counter,
> -			       response_len - TPM2_DIGEST_LEN, data,
> -			       TPM2_DIGEST_LEN))
> +			       response_len - digest_len, data,
> +			       digest_len))
>  		return TPM_LIB_ERROR;
>  
>  	if (updates)
> -- 
> 2.25.1
> 


Cheers
/Ilias