Function check_future_dataloss_fields

channeld/channeld.c:5468–5511

BOLT #2: * * A receiving node: * - MUST ignore `my_current_per_commitment_point`, but MAY require it to be * a valid point. * - if `next_revocation_number` is greater than expected above, AND * `your_last_per_commitment_secret` is correct for that * `next_revocation_number` minus 1: * - MUST NOT broadcast its commitment transaction. * - SHOULD send an `error` to

 *      - SHOULD send an `error` to request the peer to fail the channel.
 */
static void check_future_dataloss_fields(struct peer *peer,
			u64 next_revocation_number,
			const struct secret *last_local_per_commit_secret)
{
	const u8 *msg;
	bool correct;

	assert(next_revocation_number > peer->next_index[LOCAL] - 1);

	msg = towire_hsmd_check_future_secret(NULL,
					     next_revocation_number - 1,
					     last_local_per_commit_secret);
	msg = hsm_req(tmpctx, take(msg));
	if (!fromwire_hsmd_check_future_secret_reply(msg, &correct))
		status_failed(STATUS_FAIL_HSM_IO,
			      "Bad hsm_check_future_secret_reply: %s",
			      tal_hex(tmpctx, msg));

	if (!correct)
		peer_failed_err(peer->pps,
				&peer->channel_id,
				"bad future last_local_per_commit_secret: %"PRIu64
				" vs %"PRIu64,
				next_revocation_number,
				peer->next_index[LOCAL] - 1);

	/* Oh shit, they really are from the future! */
	peer_billboard(true, "They have future commitment number %"PRIu64
		       " vs our %"PRIu64". We must wait for them to close!",
		       next_revocation_number,
		       peer->next_index[LOCAL] - 1);

	/* BOLT #2:
	 * - MUST NOT broadcast its commitment transaction.
	 * - SHOULD send an `error` to request the peer to fail the channel.
	 */
	wire_sync_write(MASTER_FD,
			take(towire_channeld_fail_fallen_behind(NULL)));

	sleep(1);
	/* We have to send them an error to trigger dropping to chain. */
	peer_failed_err(peer->pps, &peer->channel_id,
			"Awaiting unilateral close");
}

/* BOLT #2:
 *