Merge #19638: Replace `hidden service` with `onion service`

1e72b68ab330c72644981508c8a1b3fa670d086f Replace `hidden service` with `onion service` (Riccardo Masutti)

Pull request description:

  For a couple of years, Tor has made the term `hidden service` obsolete, in favor of `onion service`: [Tor Project | Onion Services](https://community.torproject.org/onion-services/)

  This PR updates all the references.

ACKs for top commit:
  laanwj:
    Code review ACK 1e72b68ab330c72644981508c8a1b3fa670d086f
  hebasto:
    ACK 1e72b68ab330c72644981508c8a1b3fa670d086f, tested on Linux Mint 20 (x86_64).

Tree-SHA512: 6a29e828e1c5e1ec934b5666f67326dbd84d77c8b2641f6740abac6d3d5923b7729763b9ff2230390b0bb23359a5f3731ccd9a30011ca69004f7c820aed17262

3 files changed, 11 insertions, 11 deletions

diff --git a/doc/JSON-RPC-interface.md b/doc/JSON-RPC-interface.md
index a0cfe84a3e..40d8e330e2 100644
--- a/doc/JSON-RPC-interface.md
+++ b/doc/JSON-RPC-interface.md
@@ -60,7 +60,7 @@ RPC interface will be abused.
   are sent as clear text that can be read by anyone on your network
   path.  Additionally, the RPC interface has not been hardened to
   withstand arbitrary Internet traffic, so changing the above settings
-  to expose it to the Internet (even using something like a Tor hidden
+  to expose it to the Internet (even using something like a Tor onion
   service) could expose you to unconsidered vulnerabilities.  See
   `bitcoind -help` for more information about these settings and other
   settings described in this document.
diff --git a/doc/files.md b/doc/files.md
index 5475826329..52e094a60b 100644
--- a/doc/files.md
+++ b/doc/files.md
@@ -56,7 +56,7 @@ Subdirectory       | File(s)               | Description
 `./`               | `fee_estimates.dat`   | Stores statistics used to estimate minimum transaction fees and priorities required for confirmation
 `./`               | `guisettings.ini.bak` | Backup of former [GUI settings](#gui-settings) after `-resetguisettings` option is used
 `./`               | `mempool.dat`         | Dump of the mempool's transactions
-`./`               | `onion_private_key`   | Cached Tor hidden service private key for `-listenonion` option
+`./`               | `onion_private_key`   | Cached Tor onion service private key for `-listenonion` option
 `./`               | `peers.dat`           | Peer IP address database (custom format)
 `./`               | `settings.json`       | Read-write settings set through GUI or RPC interfaces, augmenting manual settings from [bitcoin.conf](bitcoin-conf.md). File is created automatically if read-write settings storage is not disabled with `-nosettings` option. Path can be specified with `-settings` option
 `./`               | `.cookie`             | Session RPC authentication cookie; if used, created at start and deleted on shutdown; can be specified by `-rpccookiefile` option
diff --git a/doc/tor.md b/doc/tor.md
index 2c54e32f84..17807856e5 100644
--- a/doc/tor.md
+++ b/doc/tor.md
@@ -1,6 +1,6 @@
 # TOR SUPPORT IN BITCOIN
 
-It is possible to run Bitcoin Core as a Tor hidden service, and connect to such services.
+It is possible to run Bitcoin Core as a Tor onion service, and connect to such services.
 
 The following directions assume you have a Tor proxy running on port 9050. Many distributions default to having a SOCKS proxy listening on port 9050, but others may not. In particular, the Tor Browser Bundle defaults to listening on port 9150. See [Tor Project FAQ:TBBSocksPort](https://www.torproject.org/docs/faq.html.en#TBBSocksPort) for how to properly
 configure Tor.
@@ -14,12 +14,12 @@ outgoing connections, but more is possible.
 	-proxy=ip:port  Set the proxy server. If SOCKS5 is selected (default), this proxy
 	                server will be used to try to reach .onion addresses as well.
 
-	-onion=ip:port  Set the proxy server to use for Tor hidden services. You do not
+	-onion=ip:port  Set the proxy server to use for Tor onion services. You do not
 	                need to set this if it's the same as -proxy. You can use -noonion
-	                to explicitly disable access to hidden services.
+	                to explicitly disable access to onion services.
 
 	-listen         When using -proxy, listening is disabled by default. If you want
-	                to run a hidden service (see next section), you'll need to enable
+	                to run an onion service (see next section), you'll need to enable
 	                it explicitly.
 
 	-connect=X      When behind a Tor proxy, you can specify .onion addresses instead
@@ -94,11 +94,11 @@ for normal IPv4/IPv6 communication, use:
 ## 3. Automatically listen on Tor
 
 Starting with Tor version 0.2.7.1 it is possible, through Tor's control socket
-API, to create and destroy 'ephemeral' hidden services programmatically.
+API, to create and destroy 'ephemeral' onion services programmatically.
 Bitcoin Core has been updated to make use of this.
 
 This means that if Tor is running (and proper authentication has been configured),
-Bitcoin Core automatically creates a hidden service to listen on. This will positively
+Bitcoin Core automatically creates an onion service to listen on. This will positively
 affect the number of available .onion nodes.
 
 This new feature is enabled by default if Bitcoin Core is listening (`-listen`), and
@@ -110,7 +110,7 @@ Connecting to Tor's control socket API requires one of two authentication method
 configured. It also requires the control socket to be enabled, e.g. put `ControlPort 9051`
 in `torrc` config file. For cookie authentication the user running bitcoind must have read
 access to the `CookieAuthFile` specified in Tor configuration. In some cases this is
-preconfigured and the creation of a hidden service is automatic. If permission problems
+preconfigured and the creation of an onion service is automatic. If permission problems
 are seen with `-debug=tor` they can be resolved by adding both the user running Tor and
 the user running bitcoind to the same group and setting permissions appropriately. On
 Debian-based systems the user running bitcoind can be added to the debian-tor group,
@@ -127,8 +127,8 @@ in the tor configuration file. The hashed password can be obtained with the comm
 
 ## 4. Privacy recommendations
 
-- Do not add anything but Bitcoin Core ports to the hidden service created in section 2.
-  If you run a web service too, create a new hidden service for that.
+- Do not add anything but Bitcoin Core ports to the onion service created in section 2.
+  If you run a web service too, create a new onion service for that.
   Otherwise it is trivial to link them, which may reduce privacy. Hidden
   services created automatically (as in section 3) always have only one port
   open.