services: wireguard: Support lists of gexps for most fields.

In order to support more flexibility in Wireguard configuration, ungexp the
configuration fields directly instead of ungexp-splicing a sexp
calculator. This allows for the fields to take arbitrary gexps instead of only
strings which is particularly helpful for the Pre/Post Up/Down commands.

* gnu/services/vpn.scm (wireguard-configuration-file): Ungexp configuration
lists instead of ungexp-splicing the code surrounding them.
* doc/guix.texi (VPN Services)[wireguard]: Document it.

Change-Id: If074cbb78473b6fd34e0e4e990d2ed268001d6c7
Signed-off-by: Mathieu Othacehe <othacehe@gnu.org>

1 files changed, 14 insertions, 8 deletions

diff --git a/doc/guix.texi b/doc/guix.texi
index ece73a27ae..43aa1ad71a 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -34603,13 +34603,15 @@ The wireguard package to use for this service.
 The interface name for the VPN.
 
 @item @code{addresses} (default: @code{'("10.0.0.1/32")})
-The IP addresses to be assigned to the above interface.
+List of strings or G-expressions which represent the IP addresses to be
+assigned to the above interface.
 
 @item @code{port} (default: @code{51820})
 The port on which to listen for incoming connections.
 
 @item @code{dns} (default: @code{'())})
-The DNS server(s) to announce to VPN clients via DHCP.
+List of strings or G-expressions which represent the DNS server(s) to
+announce to VPN clients via DHCP.
 
 @item @code{monitor-ips?} (default: @code{#f})
 @cindex Dynamic IP, with Wireguard
@@ -34654,16 +34656,20 @@ The authorized peers on this interface.  This is a list of
 @var{wireguard-peer} records.
 
 @item @code{pre-up} (default: @code{'()})
-The script commands to be run before setting up the interface.
+List of strings or G-expressions.  These are script snippets which will
+be executed before setting up the interface.
 
 @item @code{post-up} (default: @code{'()})
-The script commands to be run after setting up the interface.
+List of strings or G-expressions.  These are script snippets which will
+be executed after setting up the interface.
 
 @item @code{pre-down} (default: @code{'()})
-The script commands to be run before tearing down the interface.
+List of strings or G-expressions.  These are script snippets which will
+be executed before tearing down the interface.
 
 @item @code{post-down} (default: @code{'()})
-The script commands to be run after tearing down the interface.
+List of strings or G-expressions.  These are script snippets which will
+be executed after tearing down the interface.
 
 @item @code{table} (default: @code{"auto"})
 The routing table to which routes are added, as a string.  There are two
@@ -34689,8 +34695,8 @@ The optional endpoint for the peer, such as
 The peer public-key represented as a base64 string.
 
 @item @code{preshared-key} (default: @code{#f})
-An optional pre-shared key file for this peer.  The given file will not
-be autogenerated.
+An optional pre-shared key file for this peer that can be either a
+string or a G-expression.  The given file will not be autogenerated.
 
 @item @code{allowed-ips}
 A list of IP addresses from which incoming traffic for this peer is