#!/bin/bash

#
# Get an OpenVPN client configuration file
#

if [ "$DEBUG" == "1" ]; then
    set -x
fi

set -e

if [ -z "$OPENVPN" ]; then
    export OPENVPN="$PWD"
fi
if ! source "$OPENVPN/ovpn_env.sh"; then
    echo "Could not source $OPENVPN/ovpn_env.sh."
    exit 1
fi
if [ -z "$EASYRSA_PKI" ]; then
    export EASYRSA_PKI="$OPENVPN/pki"
fi

cn="$1"
parm="$2"

if [ ! -f "$EASYRSA_PKI/private/${cn}.key" ]; then
    echo "Unable to find \"${cn}\", please try again or generate the key first" >&2
    exit 1
fi

get_client_config() {
    mode="$1"
    echo "
client
nobind
dev $OVPN_DEVICE
remote-cert-tls server

remote $OVPN_CN $OVPN_PORT $OVPN_PROTO
"
    if [ "$mode" == "combined" ]; then
        echo "
<key>
$(cat $EASYRSA_PKI/private/${cn}.key)
</key>
<cert>
$(openssl x509 -in $EASYRSA_PKI/issued/${cn}.crt)
</cert>
<ca>
$(cat $EASYRSA_PKI/ca.crt)
</ca>
<tls-auth>
$(cat $EASYRSA_PKI/ta.key)
</tls-auth>
key-direction 1
"
    elif [ "$mode" == "separated" ]; then
        echo "
key ${cn}.key
ca ca.crt
cert ${cn}.crt
tls-auth ta.key 1
$OVPN_ADDITIONAL_CLIENT_CONFIG
"
    fi

    if [ "$OVPN_DEFROUTE" != "0" ];then
        echo "redirect-gateway def1"
    fi

    if [ -n "$OVPN_MTU" ]; then
        echo "tun-mtu $OVPN_MTU"
    fi

    if [ -n "$OVPN_TLS_CIPHER" ]; then
        echo "tls-cipher $OVPN_TLS_CIPHER"
    fi

    if [ -n "$OVPN_CIPHER" ]; then
        echo "cipher $OVPN_CIPHER"
    fi

    if [ -n "$OVPN_AUTH" ]; then
        echo "auth $OVPN_AUTH"
    fi

    if [ -n "$OVPN_OTP_AUTH" ]; then
        echo "auth-user-pass"
    fi

    if [ -n "$OVPN_COMP_LZO" ]; then
        echo "comp-lzo"
    fi
}

dir="$OPENVPN/clients/$cn"
case "$parm" in
    "separated")
        mkdir -p "$dir"
        get_client_config "$parm" > "$dir/${cn}.ovpn"
        cp "$EASYRSA_PKI/private/${cn}.key" "$dir/${cn}.key"
        cp "$EASYRSA_PKI/ca.crt" "$dir/ca.crt"
        cp "$EASYRSA_PKI/issued/${cn}.crt" "$dir/${cn}.crt"
        cp "$EASYRSA_PKI/ta.key" "$dir/ta.key"
        ;;
    "" | "combined")
        get_client_config "combined"
        ;;
    "combined-save")
        get_client_config "combined" > "$dir/${cn}-combined.ovpn"
        ;;
    *)
        echo "This script can produce the client configuration in to formats:" >&2
        echo "    1. combined (default): All needed configuration and cryptographic material is in one file (Use \"combined-save\" to write the configuration file in the same path as the separated parameter does)." >&2
        echo "    2. separated: Separated files." >&2
        echo "Please specific one of those options as second parameter." >&2
        ;;
esac