[SPDM 1.3] The responder should be able to generate one DIGESTS response matching with the state Exists with key.

[Zhiqiang520]

The responder should be able to generate one DIGESTS response matching with the state Exists with key.

1. Certificate slots have one state named 3. Exists with key that can be reported in the DIGESTS response.
   Refer to the paragraph 366 In DSP0274_1.3.0.pdf.
   
   Refer to the paragraph 369 Table 35 — Successful DIGESTS response message format In DSP0274_1.3.0.pdf.
   

2. But the responder will never generate one DIGESTS response matching with the above state 3. Exists with key:
   spdm_context->local_context.local_cert_chain_provision[index] = NULL
spdm_response->header.param2 |= (1 << index)
spdm_context->local_context.local_cert_info[index] = SPDM_CERTIFICATE_INFO_CERT_MODEL_NONE
digest[hash_size * slot_index] be all zeros.

libspdm/library/spdm_responder_lib/libspdm_rsp_digests.c

Lines 140 to 161 in 159ecd1

	slot_index = 0;
	for (index = 0; index < SPDM_MAX_SLOT_COUNT; index++) {
	if (spdm_context->local_context
	.local_cert_chain_provision[index] != NULL) {
	spdm_response->header.param2 |= (1 << index);
	result = libspdm_generate_cert_chain_hash(spdm_context, index,
	&digest[hash_size * slot_index]);
	if ((spdm_request->header.spdm_version >= SPDM_MESSAGE_VERSION_13) &&
	spdm_context->connection_info.multi_key_conn_rsp) {
	key_pair_id[slot_index] = spdm_context->local_context.local_key_pair_id[index];
	cert_info[slot_index] = spdm_context->local_context.local_cert_info[index];
	key_usage_bit_mask[slot_index] =
	spdm_context->local_context.local_key_usage_bit_mask[index];
	}
	slot_index++;
	if (!result) {
	return libspdm_generate_error_response(
	spdm_context, SPDM_ERROR_CODE_UNSPECIFIED,
	0, response_size, response);
	}
	}
	}

[jyao1]

This seems a new feature request.