opts: deprecate --disable-ip-discovery switch

This switch was not doing anything useful anymore.
We deprecate it anyways to notify the user about the new switch.

Changelog-Deprecated: The old --disable-ip-discovery config switch

doc/lightning-listconfigs.7.md

@@ -88,7 +88,7 @@ On success, an object is returned, containing:
 - **autolisten** (boolean, optional): `autolisten` field from config or cmdline, or default
 - **proxy** (string, optional): `proxy` field from config or cmdline, or default
 - **disable-dns** (boolean, optional): `true` if `disable-dns` was set in config or cmdline
-- **disable-ip-discovery** (boolean, optional): `true` if `disable-ip-discovery` was set in config or cmdline (DEPRECATED)
+- **disable-ip-discovery** (boolean, optional): `true` if `disable-ip-discovery` was set in config or cmdline **deprecated, removal in v23.11**
 - **announce-addr-discovered** (string, optional): `true`/`false`/`auto` depending on how `announce-addr-discovered` was set in config or cmdline *(added v23.02)*
 - **encrypted-hsm** (boolean, optional): `true` if `encrypted-hsm` was set in config or cmdline
 - **rpc-file-mode** (string, optional): `rpc-file-mode` field from config or cmdline, or default
@@ -221,4 +221,4 @@ RESOURCES
 
 Main web site: <https://github.com/ElementsProject/lightning>
 
-[comment]: # ( SHA256STAMP:fcf5e537989d9df2cf2031ff6b7589cc1d6acc30a81806e7ecedb3265b8c9b3b)
+[comment]: # ( SHA256STAMP:9953b3545acb82bed816b86a65ba51ff4b043d3848c4a3ae460aa68db1a4b542)

doc/lightningd-config.5.md

@@ -368,14 +368,6 @@ use the RPC call lightning-setchannel(7).
   Note: You also need to open TCP port 9735 on your router towords your node.
   Note: Will always be disabled if you use 'always-use-proxy'.
 
-* **disable-ip-discovery**
-
-  Turn off public IP discovery to send `node_announcement` updates that contain
-the discovered IP with TCP port 9735 as announced address. If unset and you
-open TCP port 9735 on your router towords your node, your node will remain
-connectable on changing IP addresses.  Note: Will always be disabled if you use
-'always-use-proxy'.
-
 ### Lightning channel and HTLC options
 
 * **large-channels**

doc/schemas/listconfigs.schema.json

@@ -245,7 +245,8 @@
     },
     "disable-ip-discovery": {
       "type": "boolean",
-      "description": "`true` if `disable-ip-discovery` was set in config or cmdline"
+      "description": "`true` if `disable-ip-discovery` was set in config or cmdline",
+      "deprecated": "v23.02"
     },
     "announce-addr-discovered": {
       "type": "string",

lightningd/lightningd.h

@@ -61,8 +61,6 @@ struct config {
 
 	/* Excplicitly turns 'on' or 'off' IP discovery feature. */
 	enum opt_autobool ip_discovery;
-	/* Turn off IP address announcement discovered via peer `remote_addr` */
-	bool disable_ip_discovery;
 
 	/* Minimal amount of effective funding_satoshis for accepting channels */
 	u64 min_capacity_sat;

lightningd/options.c

@@ -845,8 +845,6 @@ static const struct config testnet_config = {
 
 	/* Excplicitly turns 'on' or 'off' IP discovery feature. */
 	.ip_discovery = OPT_AUTOBOOL_AUTO,
-	/* Turn off IP address announcement discovered via peer `remote_addr` */
-	.disable_ip_discovery = false,
 
 	/* Sets min_effective_htlc_capacity - at 1000$/BTC this is 10ct */
 	.min_capacity_sat = 10000,
@@ -913,8 +911,6 @@ static const struct config mainnet_config = {
 
 	/* Excplicitly turns 'on' or 'off' IP discovery feature. */
 	.ip_discovery = OPT_AUTOBOOL_AUTO,
-	/* Turn off IP address announcement discovered via peer `remote_addr` */
-	.disable_ip_discovery = false,
 
 	/* Sets min_effective_htlc_capacity - at 1000$/BTC this is 10ct */
 	.min_capacity_sat = 10000,
@@ -1084,6 +1080,13 @@ static char *opt_set_db_upgrade(const char *arg, struct lightningd *ld)
 	return opt_set_bool_arg(arg, ld->db_upgrade_ok);
 }
 
+static char *opt_disable_ip_discovery(struct lightningd *ld)
+{
+	log_broken(ld->log, "--disable-ip-discovery has been deprecated, use --announce-addr-discovered=false");
+	ld->config.ip_discovery = OPT_AUTOBOOL_FALSE;
+	return NULL;
+}
+
 static void register_opts(struct lightningd *ld)
 {
 	/* This happens before plugins started */
@@ -1216,9 +1219,7 @@ static void register_opts(struct lightningd *ld)
 			 ld,
 			 "Set an IP address (v4 or v6) or .onion v3 to announce, but not listen on");
 
-	opt_register_noarg("--disable-ip-discovery", opt_set_bool,
-			 &ld->config.disable_ip_discovery,
-			 "Turn off announcement of discovered public IPs");
+	opt_register_noarg("--disable-ip-discovery", opt_disable_ip_discovery, ld, opt_hidden);
 	opt_register_arg("--announce-addr-discovered", opt_set_autobool_arg, opt_show_autobool,
 			 &ld->config.ip_discovery,
 			 "Explicitly turns IP discovery 'on' or 'off'.");

lightningd/peer_control.c

@@ -1308,7 +1308,8 @@ static void update_remote_addr(struct lightningd *ld,
 	u16 public_port;
 
 	/* failsafe to prevent privacy leakage. */
-	if (ld->always_use_proxy || ld->config.disable_ip_discovery)
+	if (ld->always_use_proxy ||
+	    ld->config.ip_discovery == OPT_AUTOBOOL_FALSE)
 		return;
 
 	/* Peers will have likey reported our dynamic outbound TCP port.