[PATCH v4 3/7] tpm: Correct the define-space command in TPMv2

[Ilias Apalodimas]

On Tue, 23 Aug 2022 at 20:12, Simon Glass <sjg at chromium.org> wrote:
>
> The message format is incorrect. Fix it.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>
> (no changes since v2)
>
> Changes in v2:
> - Use constants instead of open-coded values
>
>  lib/tpm-v2.c | 22 +++++++++++++++-------
>  1 file changed, 15 insertions(+), 7 deletions(-)
>
> diff --git a/lib/tpm-v2.c b/lib/tpm-v2.c
> index 6058f2e1e4f..3e240bb4c67 100644
> --- a/lib/tpm-v2.c
> +++ b/lib/tpm-v2.c
> @@ -89,14 +89,18 @@ u32 tpm2_nv_define_space(struct udevice *dev, u32 space_index,
>          * Calculate the offset of the nv_policy piece by adding each of the
>          * chunks below.
>          */
> -       uint offset = 10 + 8 + 13 + 14;
> +       const int platform_len = sizeof(u32);
> +       const int session_hdr_len = 13;
> +       const int message_len = 14;
> +       uint offset = TPM2_HDR_LEN + platform_len + session_hdr_len +
> +               message_len;
>         u8 command_v2[COMMAND_BUFFER_SIZE] = {
>                 /* header 10 bytes */
>                 tpm_u16(TPM2_ST_SESSIONS),      /* TAG */
> -               tpm_u32(offset + nv_policy_size),/* Length */
> +               tpm_u32(offset + nv_policy_size + 2),/* Length */
>                 tpm_u32(TPM2_CC_NV_DEFINE_SPACE),/* Command code */
>
> -               /* handles 8 bytes */
> +               /* handles 4 bytes */
>                 tpm_u32(TPM2_RH_PLATFORM),      /* Primary platform seed */
>
>                 /* session header 13 bytes */
> @@ -107,12 +111,15 @@ u32 tpm2_nv_define_space(struct udevice *dev, u32 space_index,
>                 tpm_u16(0),                     /* auth_size */
>
>                 /* message 14 bytes + policy */
> -               tpm_u16(12 + nv_policy_size),   /* size */
> +               tpm_u16(message_len + nv_policy_size),  /* size */
>                 tpm_u32(space_index),
>                 tpm_u16(TPM2_ALG_SHA256),
>                 tpm_u32(nv_attributes),
>                 tpm_u16(nv_policy_size),
> -               /* nv_policy */
> +               /*
> +                * nv_policy
> +                * space_size
> +                */
>         };
>         int ret;
>
> @@ -120,8 +127,9 @@ u32 tpm2_nv_define_space(struct udevice *dev, u32 space_index,
>          * Fill the command structure starting from the first buffer:
>          *     - the password (if any)
>          */
> -       ret = pack_byte_string(command_v2, sizeof(command_v2), "s",
> -                              offset, nv_policy, nv_policy_size);
> +       ret = pack_byte_string(command_v2, sizeof(command_v2), "sw",
> +                              offset, nv_policy, nv_policy_size,
> +                              offset + nv_policy_size, space_size);
>         if (ret)
>                 return TPM_LIB_ERROR;
>
> --
> 2.37.2.609.g9ff673ca1a-goog
>

Acked-by: Ilias Apalodimas <ilias.apalodimas at linaro.org>