TCBInfo format issue

[reasly]

Current
/os_stub/spdm_cert_verify_callback_sample/spdm_cert_verify_callback.c
has the following code:

    result = libspdm_asn1_get_tag(&ptr, end, &obj_len,
                                  LIBSPDM_CRYPTO_ASN1_SEQUENCE | LIBSPDM_CRYPTO_ASN1_CONSTRUCTED);
    if (!result) {
        *spdm_get_dice_tcb_info_size = 0;
        return false;
    }
    result = libspdm_asn1_get_tag(&ptr, end, &obj_len,
                                  LIBSPDM_CRYPTO_ASN1_SEQUENCE | LIBSPDM_CRYPTO_ASN1_CONSTRUCTED);
    if (!result) {
        *spdm_get_dice_tcb_info_size = 0;
        return false;
    }

The code requires the extension has "SEQUENCE (SEQUENCE (xxx))" structure.
However, according to DICE Attestation Architecture (https://trustedcomputinggroup.org/wp-content/uploads/DICE-Attestation-Architecture-v1.2_pub.pdf) :

tcg-dice-TcbInfo OBJECT IDENTIFIER ::= {tcg-dice tcbinfo(1)}
DiceTcbInfo ::== SEQUENCE { ...}

The DICETCBInfo should have only one layer of SEQUENCE.

tcg-dice-MultiTcbInfo OBJECT IDENTIFIER ::= {tcg-dice multi-tcbinfo(5)}
DiceTcbInfoSeq ::= SEQUENCE SIZE (1..MAX) OF DiceTcbInfo

Only MultiDICETCBInfo can have SEQUENCE(SEQUENCE(...)) structure.

Please help chech if our understanding is correct.

[steven-bellock]

That is consistent with what @jyao1 said in #2672 (comment) :

Only one reference TcbInfo entry is provided by the integrator. (Multiple reference TcbInfo is NOT supported in this PR.)

[jyao1]

@reasly, please feel free to submit PR to fix the issue if you want.