Function blindedpath_next_path_key

common/blindedpath.c:240–260

}

void blindedpath_next_path_key(const struct tlv_encrypted_data_tlv *enc,
			       const struct pubkey *path_key,
			       const struct secret *ss,
			       struct pubkey *next_path_key)
{
	/* BOLT #4:
	 *   - $`E_{i+1} = SHA256(E_i || ss_i) * E_i`$
	 * ...
	 * - If the `encrypted_data_tlv` contains a `next_path_key_override`:
	 *   - MUST use it as the next `path_key`.
	 * - Otherwise:
	 *  - MUST use $`E_{i+1} = SHA256(E_i || ss_i) * E_i`$ as the next `path_key`
	 */
	if (enc->next_path_key_override)
		*next_path_key = *enc->next_path_key_override;
	else {
		struct sha256 h;
		blinding_hash_e_and_ss(path_key, ss, &h);
		blinding_next_path_key(path_key, &h, next_path_key);
	}
}