lightningd: partial BOLT update.

Not the new onion stuff for now.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

lightningd/opening/opening.c

@@ -351,7 +351,7 @@ static u8 *open_channel(struct state *state,
 
 	/* BOLT #2:
 	 *
-	 * This message introduces the `channel-id` which identifies , which
+	 * This message introduces the `channel-id` to identify the channel, which
 	 * is derived from the funding transaction by combining the
 	 * `funding-txid` and the `funding-output-index` using big-endian
 	 * exclusive-OR (ie. `funding-output-index` alters the last two
@@ -590,8 +590,8 @@ static u8 *recv_channel(struct state *state,
 
 	/* BOLT #2:
 	 *
-	 * This message introduces the `channel-id` which identifies , which
+	 * This message introduces the `channel-id` to identify the channel,
-	 * is derived from the funding transaction by combining the
+	 * which is derived from the funding transaction by combining the
 	 * `funding-txid` and the `funding-output-index` using big-endian
 	 * exclusive-OR (ie. `funding-output-index` alters the last two
 	 * bytes).

lightningd/peer_control.c

@@ -674,8 +674,10 @@ static void handle_localpay(struct htlc_end *hend,
 	/* BOLT #4:
 	 *
 	 * If the amount paid is less than the amount expected, the final node
-	 * MUST fail the HTLC.  If the amount paid is more than the amount
+	 * MUST fail the HTLC.  If the amount paid is more than twice the
-	 * expected, the final node SHOULD fail the HTLC:
+	 * amount expected, the final node SHOULD fail the HTLC.  This allows
+	 * the sender to reduce information leakage by altering the amount,
+	 * without allowing accidental gross overpayment:
 	 *
 	 * 1. type: PERM|16 (`incorrect_payment_amount`)
 	 */

wire/fromwire.c

@@ -182,7 +182,7 @@ REGISTER_TYPE_TO_HEXSTR(channel_id);
 
 /* BOLT #2:
  *
- * This message introduces the `channel-id` which identifies , which is
+ * This message introduces the `channel-id` to identify the channel, which is
  * derived from the funding transaction by combining the `funding-txid` and
  * the `funding-output-index` using big-endian exclusive-OR
  * (ie. `funding-output-index` alters the last two bytes).