-source vars # dun care about setting cert cn etc from the non-example values
-./clean-all
-# accept default prompts
-echo -e '\n\n\n\n\n\n\n\n' | ./build-ca
-
-# This builds the server's key/cert. argument is the name of the file,
-# but it also is the default common name of the cert.
-# 'server' is the default name in our conf file for the name of the file
-# and I've seen no reason to change it.
-# Note, this is not idempotent.
-{ echo -e '\n\n\n\n\n\n\n\n\n\n'; sleep 1; echo -e 'y\ny\n'; } | ./build-key-server server
-./build-dh
-cp /usr/share/doc/openvpn/examples/sample-config-files/server.conf.gz /etc/openvpn/
-cp /etc/openvpn/easy-rsa/keys/{ca.crt,server.{crt,key},dh2048.pem} /etc/openvpn
-gzip -df /etc/openvpn/server.conf.gz
-sed -i --follow-symlinks 's/^dh dh1024.pem/dh dh2048.pem/' /etc/openvpn/server.conf
-
-teeu() {
- while read -r line; do
- grep -xFq "$line" "$1" || echo "$line" | tee -a "$1"
- done
-}
+if [[ -e openssl-1.0.0.cnf && ! -e openssl.cnf ]]; then
+ # there's a debian bug about this.
+ ln -s openssl-1.0.0.cnf openssl.cnf
+fi
+
+server_dir=/etc/openvpn/server
+mkdir -p $server_dir
+chmod 700 $server_dir
+
+
+new=true
+keyfiles=(/etc/openvpn/easy-rsa/pki/{ca.crt,private/server.key,issued/server.crt})
+if [[ -e /etc/openvpn/easy-rsa/build-ca ]]; then
+ new=false
+ keyfiles=(/etc/openvpn/easy-rsa/keys/{ca.crt,server.{crt,key}})
+fi
+
+keys_exist=true
+for f in ${keyfiles[@]}; do
+ if [[ ! -e $f ]]; then
+ keys_exist=false
+ break
+ fi
+done
+
+if ! $keys_exist; then
+ # newer sample configs (post stretch) use ta.key. no harm making it for earlier oses
+ openvpn --genkey --secret $server_dir/ta.key
+ if $new; then
+ ./easyrsa init-pki
+ ./easyrsa --batch build-ca nopass
+ ./easyrsa build-server-full server nopass
+ openssl dhparam -out $server_dir/dh2048.pem 2048
+ else
+ # dun care about settning cert cn etc from the non-example values
+ source vars
+ # doesnt exist in buster
+ ./clean-all # note: removes and creates /etc/openvpn/easy-rsa/keys
+ # accept default prompts
+ echo -e '\n\n\n\n\n\n\n\n' | ./build-ca
+
+ # This builds the server's key/cert. argument is the name of the file,
+ # but it also is the default common name of the cert.
+ # 'server' is the default name in our conf file for the name of the file
+ # and I've seen no reason to change it.
+ # Note, this is not idempotent.
+ { echo -e '\n\n\n\n\n\n\n\n\n\n'; sleep 1; echo -e 'y\ny\n'; } | ./build-key-server server
+ ./build-dh
+ fi
+fi
+
+
+cp /usr/share/doc/openvpn/examples/sample-config-files/server.conf.gz $server_dir
+gzip -df $server_dir/server.conf.gz
+
+
+cp ${keyfiles[@]} $server_dir
+# for legacy systems
+for f in ${keyfiles[@]}; do
+ ln -sf server/${f##*/} /etc/openvpn
+done
+
+cat >>$server_dir/server.conf <<'EOF'
+
+# I cat an extra blank line to start because the example config does
+# not have a final newline. ....
+
+# not in example config, but openvpn outputs a warning about insecure
+# cipher without a setting like this (the default i can understand due
+# to compatibility issues, but not changing the example config... not
+# cool).
+# requires the same setting on the client side.
+cipher AES-256-CBC
+# just sets up the ability to have client specific configs
+client-config-dir /etc/openvpn/client-config
+
+# duplicate in newer sample configs
+tls-auth ta.key 0 # This file is secret
+
+# depending on sample config, this may not be there, which means i can't
+# talk to 10.8.0.1, there might be some other way, but stretch's
+# sample config says:
+# Should be subnet (addressing via IP)
+# unless Windows clients v2.0.9 and lower have to
+# be supported (then net30, i.e. a /30 per client)
+# Defaults to net30 (not recommended)
+topology subnet
+EOF