➢ pkey = PEM_read_bio_PUBKEY(bio, NULL, ossl_pem_passwd_cb, (void *)pass); That only reads PEM files. If docs say otherwise, they are wrong. ➢ There must be a way to read DER format public keys. A raw public key? Or a cert? Or a pkcs object? Anyhow, doc/man3/d2i_X509.pod in master.