Add compile options to libspdm_gen_x509_csr

[rw8896]

libspdm/os_stub/cryptlib_mbedtls/pk/x509.c

Line 1993 in b327ead

bool libspdm_gen_x509_csr(size_t hash_nid, size_t asym_nid,

libspdm/os_stub/cryptlib_openssl/pk/x509.c

Line 2495 in b327ead

bool libspdm_gen_x509_csr(size_t hash_nid, size_t asym_nid,

The implementation could use LIBSPDM_ENABLE_CAPABILITY_CSR_CAP to wrap the whole function.
And it should add crypto options (e.g. LIBSPDM_RSA_SSA_2048_SUPPORT) to wrap around the crypto operation code.

[steven-bellock]

@rw8896 is this to save on code size?

[rw8896]

Not really. It caused compiler errors as RSA was not enabled in my mbedtls configuration.

After looking into this function further, I think it doesn't allow the caller to specify the pathLen in basic constraints.
If that's the case, maybe pathLen should be added as a input to make this API more general?

[jyao1]

@rw8896 , I am not sure if I understand your problem statement.

Usually, it is more helpful to describe what problem you have meet, than just describe the solution.

May I know what compiler error you have meet?

Based on my understand, if you customize the mbedtls, then you can also customize the cryptolib_mbedtls.

[rw8896]

The following code calls mbedtls_pk_rsa but mbedtls_pk_rsa is not declared/implemented when MBEDTLS_RSA_C is not defined.

libspdm/os_stub/cryptlib_mbedtls/pk/x509.c

Lines 2034 to 2055 in b327ead

	case LIBSPDM_CRYPTO_NID_RSASSA2048:
	case LIBSPDM_CRYPTO_NID_RSAPSS2048:
	case LIBSPDM_CRYPTO_NID_RSASSA3072:
	case LIBSPDM_CRYPTO_NID_RSAPSS3072:
	case LIBSPDM_CRYPTO_NID_RSASSA4096:
	case LIBSPDM_CRYPTO_NID_RSAPSS4096:
	ret = mbedtls_pk_setup(&key, mbedtls_pk_info_from_type(MBEDTLS_PK_RSA));
	if (ret != 0) {
	LIBSPDM_DEBUG((LIBSPDM_DEBUG_INFO,"failed\n ! mbedtls_pk_setup %d", ret));
	goto free_all;
	}
	ret = mbedtls_rsa_copy(mbedtls_pk_rsa(key), (mbedtls_rsa_context *)context);
	if (ret != 0) {
	LIBSPDM_DEBUG((LIBSPDM_DEBUG_INFO,"failed\n ! mbedtls_rsa_copy %d", ret));
	goto free_all;
	}
	ret = mbedtls_rsa_complete(mbedtls_pk_rsa(key));
	if (ret != 0) {
	LIBSPDM_DEBUG((LIBSPDM_DEBUG_INFO,"failed\n ! mbedtls_rsa_complete %d", ret));
	goto free_all;
	}
	break;