X-Git-Url: https://iankelling.org/git/?p=vpn-setup;a=blobdiff_plain;f=vpn-server-setup;h=0710dc801072e749df602364226a5fbd216d082b;hp=8cfe54576aaeb0d4bd945924553b330661e71b2f;hb=HEAD;hpb=95755ebea37097aa31a5f8a1acbb5cfb5d4bd06a

diff --git a/vpn-server-setup b/vpn-server-setup
index 8cfe545..c135d4e 100755
--- a/vpn-server-setup
+++ b/vpn-server-setup
@@ -1,5 +1,12 @@
 #!/bin/bash
-# Copyright (C) 2016 Ian Kelling
+# I, Ian Kelling, follow the GNU license recommendations at
+# https://www.gnu.org/licenses/license-recommendations.en.html. They
+# recommend that small programs, < 300 lines, be licensed under the
+# Apache License 2.0. This file contains or is part of one or more small
+# programs. If a small program grows beyond 300 lines, I plan to switch
+# its license to GPL.
+
+# Copyright 2024 Ian Kelling
 
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -21,23 +28,28 @@ trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" returned $?" >&2' ERR
 
 usage() {
   cat <<'EOF'
-usage: ${0##*/} [OPTIONS] [IPV6_ADDR/BITS IPV6_DEFAULT_ROUTE]
-
--4  I prefix of range for ipv4, default 10.8.0
--d  Do not push dns
--n  Name. default = server. 2 servers on the same host need different names.
--p  Port. default 1194
--r  Do not push default route
--s  Do not start openvpn
+usage: ${0##*/} [OPTIONS] [IPV6_ADDR/BITS]
+
+-4   Prefix of range for ipv4, default 10.8.0
+-6  IP6_NETWORK  Do ip6 nat for this network. ipv6 will work without nat,
+     but you may want it in certain circumstances.
+-d   Do not push dns
+-i INTERFACE_NAME name of tun interface
+-n  NAME  default = server. 2 servers on the same host need different names.
+-p  PORT  default 1194
+-r   Do not push default route
+-s   Do not start openvpn
 -h --help print help
 
+IPV6_ADDR/BITS    Ipv6 address of the vpn interface.
+
 Sets up a vpn server which pushes gateway route and dns server so all
 traffic goes through the vpn. requires systemd, and might have some
 debian specific paths.
 
 For ipv6, we assume ipv6_addr routes to the server.
 
-You can save all the keys by storing /etc/openvpn/easy-rsa/keys, and
+You can save all the keys by storing /etc/openvpn/easy-rsa-NAME/keys, and
 the script will not generate them if it sees they exist already.
 
 For future updates to this script, this is a good place to
@@ -54,12 +66,14 @@ route=true
 start=true
 ip4=10.8.0
 name=server
-temp=$(getopt -l help 4:dn:p:rsh "$@") || usage 1
+temp=$(getopt -l help 4:6:di:n:p:rsh "$@") || usage 1
 eval set -- "$temp"
 while true; do
   case $1 in
     -4) ip4=$2; shift 2 ;;
+    -6) ip6net=$2; shift 2 ;;
     -d) dns=false; shift ;;
+    -i) ifname=$2; shift 2 ;;
     -n) name=$2; shift 2 ;;
     -p) port=$2; shift 2 ;;
     -r) route=false; shift ;;
@@ -74,7 +88,7 @@ read -r ip6 ip6route <<<"$@"
 
 source /a/bin/distro-functions/src/package-manager-abstractions
 
-pi-nostart openvpn openssl resolvconf easy-rsa uuid-runtime
+pi-nostart openvpn openssl easy-rsa uuid-runtime
 
 if [[ -e /lib/systemd/system/openvpn-server@.service ]]; then
   vpn_service=openvpn-server@$name
@@ -136,7 +150,7 @@ if ! $keys_exist; then
     echo 'set_var EASYRSA_NS_SUPPORT      "yes"' >vars
     ./easyrsa init-pki
     ./easyrsa --batch build-ca nopass
-    ./easyrsa build-server-full $name nopass
+    ./easyrsa --days=3650 build-server-full $name nopass
   else
     # dun care about settning cert cn etc from the non-example values
     source vars
@@ -155,8 +169,12 @@ if ! $keys_exist; then
   fi
 fi
 
-
-gzip -dc /usr/share/doc/openvpn/examples/sample-config-files/server.conf.gz >$conf
+if [[ -e /usr/share/doc/openvpn/examples/sample-config-files/server.conf ]]; then
+  cat /usr/share/doc/openvpn/examples/sample-config-files/server.conf >$conf
+else
+  # pre-bullsye name
+  gzip -dc /usr/share/doc/openvpn/examples/sample-config-files/server.conf.gz >$conf
+fi
 
 cafile=$server_dir/ca-$name.crt
 cp $ca_origin $cafile
@@ -217,10 +235,17 @@ push "dhcp-option DNS $ip4.1"
 EOF
 fi
 
+if [[ $ifname ]]; then
+  cat >>$conf <<EOF
+dev $ifname
+EOF
+fi
+
 if [[ $ip6 ]]; then
   cat >>$conf <<EOF
 push tun-ipv6 # legacy option that flidas needs, has no harm.
-ifconfig-ipv6 $ip6 $ip6route
+# the ::1 is not used, i just put a short valid address there
+ifconfig-ipv6 $ip6 ::1
 EOF
 
   sed -i --follow-symlinks '/^ *net.ipv6.conf.all.forwarding=.*/d' /etc/sysctl.conf
@@ -257,24 +282,23 @@ sysctl -p /etc/sysctl.conf
 
 gw=$(ip route | sed -rn 's/^default via .* dev (\S+).*/\1/p' | head -n1)
 
-cat >/etc/systemd/system/vpnnat.service <<EOF
-[Unit]
-Description=Turns on nat iptables setting
-
+d=/etc/systemd/system/$vpn_service.service.d
+mkdir -p $d
+f=$d/nat.conf
+cat >$f <<EOF
 [Service]
-Type=oneshot
-RemainAfterExit=yes
-ExecStart=/sbin/iptables -t nat -A POSTROUTING -s $ip4.0/24 -o $gw -j MASQUERADE
-ExecStop=/sbin/iptables -t nat -D POSTROUTING -s $ip4.0/24 -o $gw -j MASQUERADE
-
-[Install]
-WantedBy=$vpn_service.service
+ExecStartPre=/sbin/iptables -t nat -A POSTROUTING -s $ip4.0/24 -o $gw -j MASQUERADE
+ExecStopPost=/sbin/iptables -t nat -D POSTROUTING -s $ip4.0/24 -o $gw -j MASQUERADE
+EOF
+if [[ $ip6net ]]; then
+  cat >>$f <<EOF
+ExecStartPre=/sbin/ip6tables -t nat -A POSTROUTING -s $ip6net -o $gw -j MASQUERADE
+ExecStopPost=/sbin/ip6tables -t nat -D POSTROUTING -s $ip6net -o $gw -j MASQUERADE
 EOF
-systemctl daemon-reload # needed if the file was already there
-# note, no need to start it, the vpn_service does that.
-systemctl enable vpnnat
+  systemctl daemon-reload # needed if the file was already there
 
-if $start; then
-  systemctl enable $vpn_service
-  systemctl restart $vpn_service
+  if $start; then
+    systemctl enable $vpn_service
+    systemctl restart $vpn_service
+  fi
 fi