hsmd: Add hsmd_forget_channel to tell hsmd to delete a channel

Changelog-Added: Explicitly tell hsmd when it is time to forget a channel
lightning-signer · Dec 4, 2023 · 798ace6 · 798ace6
1 parent 2f5f098
commit 798ace6
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Showing 5 changed files with 49 additions and 0 deletions.
diff --git a/hsmd/hsmd.c b/hsmd/hsmd.c
@@ -647,6 +647,7 @@ static struct io_plan *handle_client(struct io_conn *conn, struct client *c)
 	case WIRE_HSMD_SETUP_CHANNEL:
  	case WIRE_HSMD_CHECK_OUTPOINT:
  	case WIRE_HSMD_LOCK_OUTPOINT:
+ 	case WIRE_HSMD_FORGET_CHANNEL:
 	case WIRE_HSMD_SIGN_COMMITMENT_TX:
 	case WIRE_HSMD_VALIDATE_COMMITMENT_TX:
 	case WIRE_HSMD_VALIDATE_REVOCATION:
@@ -694,6 +695,7 @@ static struct io_plan *handle_client(struct io_conn *conn, struct client *c)
 	case WIRE_HSMD_SETUP_CHANNEL_REPLY:
 	case WIRE_HSMD_CHECK_OUTPOINT_REPLY:
 	case WIRE_HSMD_LOCK_OUTPOINT_REPLY:
+ 	case WIRE_HSMD_FORGET_CHANNEL_REPLY:
 	case WIRE_HSMD_NODE_ANNOUNCEMENT_SIG_REPLY:
 	case WIRE_HSMD_SIGN_WITHDRAWAL_REPLY:
 	case WIRE_HSMD_SIGN_INVOICE_REPLY:

diff --git a/hsmd/hsmd_wire.csv b/hsmd/hsmd_wire.csv
@@ -105,6 +105,14 @@ msgdata,hsmd_lock_outpoint,funding_txout,u16,
 # No value returned.
 msgtype,hsmd_lock_outpoint_reply,137
 
+# Forget channel.
+msgtype,hsmd_forget_channel,34
+msgdata,hsmd_forget_channel,id,node_id,
+msgdata,hsmd_forget_channel,dbid,u64,
+
+# No value returned.
+msgtype,hsmd_forget_channel_reply,134
+
 # Return signature for a funding tx.
 #include <common/utxo.h>
 

diff --git a/hsmd/libhsmd.c b/hsmd/libhsmd.c
@@ -118,6 +118,7 @@ bool hsmd_check_client_capabilities(struct hsmd_client *client,
 
 	case WIRE_HSMD_INIT:
 	case WIRE_HSMD_NEW_CHANNEL:
+ 	case WIRE_HSMD_FORGET_CHANNEL:
 	case WIRE_HSMD_CLIENT_HSMFD:
 	case WIRE_HSMD_SIGN_WITHDRAWAL:
 	case WIRE_HSMD_SIGN_INVOICE:
@@ -150,6 +151,7 @@ bool hsmd_check_client_capabilities(struct hsmd_client *client,
 	case WIRE_HSMD_SETUP_CHANNEL_REPLY:
 	case WIRE_HSMD_CHECK_OUTPOINT_REPLY:
 	case WIRE_HSMD_LOCK_OUTPOINT_REPLY:
+ 	case WIRE_HSMD_FORGET_CHANNEL_REPLY:
 	case WIRE_HSMD_NODE_ANNOUNCEMENT_SIG_REPLY:
 	case WIRE_HSMD_SIGN_WITHDRAWAL_REPLY:
 	case WIRE_HSMD_SIGN_INVOICE_REPLY:
@@ -382,6 +384,21 @@ static u8 *handle_setup_channel(struct hsmd_client *c, const u8 *msg_in)
 	return towire_hsmd_setup_channel_reply(NULL);
 }
 
+/* ~This stub implementation is overriden by fully validating signers
+ * that need to manage per-channel state. */
+static u8 *handle_forget_channel(struct hsmd_client *c, const u8 *msg_in)
+{
+	struct node_id peer_id;
+	u64 dbid;
+
+	if (!fromwire_hsmd_forget_channel(msg_in, &peer_id, &dbid))
+		return hsmd_status_malformed_request(c, msg_in);
+
+	/* Stub implementation */
+
+	return towire_hsmd_forget_channel_reply(NULL);
+}
+
 /* ~This stub implementation is overriden by fully validating signers
  * to ensure they are caught up when outpoints are freshly buried */
 static u8 *handle_check_outpoint(struct hsmd_client *c, const u8 *msg_in)
@@ -1945,6 +1962,8 @@ u8 *hsmd_handle_client_message(const tal_t *ctx, struct hsmd_client *client,
 		return handle_check_outpoint(client, msg);
 	case WIRE_HSMD_LOCK_OUTPOINT:
 		return handle_lock_outpoint(client, msg);
+	case WIRE_HSMD_FORGET_CHANNEL:
+		return handle_forget_channel(client, msg);
 	case WIRE_HSMD_GET_OUTPUT_SCRIPTPUBKEY:
 		return handle_get_output_scriptpubkey(client, msg);
 	case WIRE_HSMD_CHECK_FUTURE_SECRET:
@@ -2024,6 +2043,7 @@ u8 *hsmd_handle_client_message(const tal_t *ctx, struct hsmd_client *client,
 	case WIRE_HSMD_SETUP_CHANNEL_REPLY:
 	case WIRE_HSMD_CHECK_OUTPOINT_REPLY:
 	case WIRE_HSMD_LOCK_OUTPOINT_REPLY:
+ 	case WIRE_HSMD_FORGET_CHANNEL_REPLY:
 	case WIRE_HSMD_NODE_ANNOUNCEMENT_SIG_REPLY:
 	case WIRE_HSMD_SIGN_WITHDRAWAL_REPLY:
 	case WIRE_HSMD_SIGN_INVOICE_REPLY:
@@ -2067,6 +2087,7 @@ u8 *hsmd_init(struct secret hsm_secret,
 		WIRE_HSMD_SIGN_HTLC_TX_MINGLE,
 		WIRE_HSMD_SIGN_SPLICE_TX,
 		WIRE_HSMD_CHECK_OUTPOINT,
+		WIRE_HSMD_FORGET_CHANNEL,
 	};
 
 	/*~ Don't swap this. */

diff --git a/lightningd/channel.c b/lightningd/channel.c
@@ -89,9 +89,21 @@ static void destroy_channel(struct channel *channel)
 
 void delete_channel(struct channel *channel STEALS)
 {
+	const u8 *msg;
+
 	struct peer *peer = channel->peer;
 	if (channel->dbid != 0)
 		wallet_channel_close(channel->peer->ld->wallet, channel->dbid);
+
+	/* Tell the hsm to forget the channel, needs to be after it's
+	 * been forgotten here */
+	if (hsm_capable(channel->peer->ld, WIRE_HSMD_FORGET_CHANNEL)) {
+		msg = towire_hsmd_forget_channel(NULL, &channel->peer->id, channel->dbid);
+		msg = hsm_sync_req(tmpctx, channel->peer->ld, take(msg));
+		if (!fromwire_hsmd_forget_channel_reply(msg))
+			fatal("HSM gave bad hsm_forget_channel_reply %s", tal_hex(msg, msg));
+	}
+
 	tal_free(channel);
 
 	maybe_delete_peer(peer);

diff --git a/wallet/test/run-wallet.c b/wallet/test/run-wallet.c
@@ -272,6 +272,9 @@ bool fromwire_hsmd_init_reply_v4(const tal_t *ctx UNNEEDED, const void *p UNNEED
 /* Generated stub for fromwire_hsmd_new_channel_reply */
 bool fromwire_hsmd_new_channel_reply(const void *p UNNEEDED)
 { fprintf(stderr, "fromwire_hsmd_new_channel_reply called!\n"); abort(); }
+/* Generated stub for fromwire_hsmd_forget_channel_reply */
+bool fromwire_hsmd_forget_channel_reply(const void *p UNNEEDED)
+{ fprintf(stderr, "fromwire_hsmd_forget_channel_reply called!\n"); abort(); }
 /* Generated stub for fromwire_hsmd_sign_commitment_tx_reply */
 bool fromwire_hsmd_sign_commitment_tx_reply(const void *p UNNEEDED, struct bitcoin_signature *sig UNNEEDED)
 { fprintf(stderr, "fromwire_hsmd_sign_commitment_tx_reply called!\n"); abort(); }
@@ -1008,6 +1011,9 @@ u8 *towire_hsmd_init(const tal_t *ctx UNNEEDED, const struct bip32_key_version *
 /* Generated stub for towire_hsmd_new_channel */
 u8 *towire_hsmd_new_channel(const tal_t *ctx UNNEEDED, const struct node_id *id UNNEEDED, u64 dbid UNNEEDED)
 { fprintf(stderr, "towire_hsmd_new_channel called!\n"); abort(); }
+/* Generated stub for towire_hsmd_forget_channel */
+u8 *towire_hsmd_forget_channel(const tal_t *ctx UNNEEDED, const struct node_id *id UNNEEDED, u64 dbid UNNEEDED)
+{ fprintf(stderr, "towire_hsmd_forget_channel called!\n"); abort(); }
 /* Generated stub for towire_hsmd_sign_commitment_tx */
 u8 *towire_hsmd_sign_commitment_tx(const tal_t *ctx UNNEEDED, const struct node_id *peer_id UNNEEDED, u64 channel_dbid UNNEEDED, const struct bitcoin_tx *tx UNNEEDED, const struct pubkey *remote_funding_key UNNEEDED, u64 commit_num UNNEEDED)
 { fprintf(stderr, "towire_hsmd_sign_commitment_tx called!\n"); abort(); }