}
		// ctx takes ownership of label, so malloc a copy for BoringCrypto to free.
		clabel := (*C.uint8_t)(C._goboringcrypto_OPENSSL_malloc(C.size_t(len(label))))
		if clabel == nil {
			return pkey, ctx, fail("OPENSSL_malloc")
		}
		copy((*[1 << 30]byte)(unsafe.Pointer(clabel))[:len(label)], label)
		if C._goboringcrypto_EVP_PKEY_CTX_set0_rsa_oaep_label(ctx, clabel, C.size_t(len(label))) == 0 {