ossl_cmp_hdr_get0_senderNonce
ASN1_OCTET_STRING *ossl_cmp_hdr_get0_senderNonce(const OSSL_CMP_PKIHEADER *hdr);
header_nonce = ossl_cmp_hdr_get0_senderNonce(fixture->hdr);
sn = ossl_cmp_hdr_get0_senderNonce(fixture->hdr);
ASN1_OCTET_STRING_cmp(ossl_cmp_hdr_get0_senderNonce(hdr),