X-Git-Url: https://iankelling.org/git/?p=vpn-setup;a=blobdiff_plain;f=vpn-mk-client-cert;h=d495754fac80df39b1f1fb7f4e7593cd0e9bb436;hp=9dc75f4c46395ce2f89dcb41d7fc9c31fbb69d83;hb=db7cd23a75387ecb417b4b621d6610bc6ff4eb6d;hpb=b9013116e0c8822917d8a199424bf726896dcf34

diff --git a/vpn-mk-client-cert b/vpn-mk-client-cert
index 9dc75f4..d495754 100755
--- a/vpn-mk-client-cert
+++ b/vpn-mk-client-cert
@@ -13,56 +13,170 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-# usage: $0 SERVER_HOST [DEST_HOST]
-# ssh to SERVER_HOST, create a cert & client config, put it on
-# DEST_HOST, or localhost by default. Assumes server was setup
-# by the other script in this dir.
-
 set -eE -o pipefail
 trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" returned $?" >&2' ERR
 
 [[ $EUID == 0 ]] || exec sudo -E "$BASH_SOURCE" "$@"
 
+
 usage() {
     cat <<EOF
-usage: ${0##*/} VPN_SERVER_HOST [CLIENT_HOST]
+usage: ${0##*/} VPN_SERVER_HOST
+
+-b COMMON_NAME   By default, use $HOSTNAME or $CLIENT_HOST. If the cert
+                 already exists on the server, with the CLIENT_NAME
+                 name, we use the existing one. See comment below if we
+                 ever want to check existing common names. They must be
+                 unique per server, so you can use $(uuidgen) if
+                 needed. You used to be able to create multiple with the
+                 same name, but not connect at the same time, but now,
+                 the generator keeps track, so you can't generate.
+-c CLIENT_HOST   default is localhost. Else we ssh to root@CLIENT_HOST
+-n CONFIG_NAME   default is client
+-s SCRIPT_PATH   Use custom up/down script at PATH, copied to same path
+                 on client.
 
 Generate a client cert and config and install it on locally or on
 CLIENT_HOST if given.  Uses default config options, and expects be able
-to ssh to VPN_SERVER_HOST and CLIENT_HOST.
+to ssh to VPN_SERVER_HOST and CLIENT_HOST as root, or if CLIENT_HOST is
+localhost, just to sudo this script as root.
+
+
+
+
+Note: Uses GNU getopt options parsing style
 EOF
     exit ${1:-0}
 }
 
-case $1 in
-    -h|--help) usage 0 ;;
-esac
+# to get the common name
+# cn=$(s openssl x509 -noout -nameopt multiline -subject \
+    #        -in /etc/openvpn/client/mail.crt | \
+    #          sed -rn 's/^\s*commonName\s*=\s*(.*)/\1/p')
 
-(($# <= 1)) || usage 1
 
-host=$1
+####### begin command line parsing and checking ##############
+
 shell="bash -c"
-if [[ $2 ]]; then
-    shell="ssh $2"
+name=client
+custom_script=false
+script=/etc/openvpn/update-resolv-conf
+
+temp=$(getopt -l help hb:c:n:s: "$@") || usage 1
+eval set -- "$temp"
+while true; do
+    case $1 in
+        -b) common_name="$2"; shift 2 ;;
+        -c) client_host=$2; shell="ssh root@$client_host"; shift 2 ;;
+        -n) name="$2"; shift 2 ;;
+        -s) custom_script=true; script="$2"; shift 2 ;;
+        -h|--help) usage ;;
+        --) shift; break ;;
+        *) echo "$0: Internal error! unexpected args: $*" ; exit 1 ;;
+    esac
+done
+
+if [[ ! $common_name ]]; then
+    if [[ $client_host ]]; then
+        common_name=$client_host
+    else
+        common_name=$HOSTNAME
+    fi
 fi
 
+host=$1
+[[ $host ]] || usage 1
+
+####### end command line parsing and checking ##############
+
+
 # bash or else we get motd spam. note sleep 2, sleep 1 failed.
-ssh $host bash <<EOF | $shell 'id -u | grep -xF 0 || s=sudo; $s tar xzv -C /etc/openvpn'
+ssh root@$host bash <<EOF | $shell 'id -u | grep -xF 0 || s=sudo; $s tar xzv -C /etc/openvpn/client'
 set -eE -o pipefail
-cd /etc/openvpn/easy-rsa
-source vars >/dev/null
 
-# uuidgen because common name must be unique
-{ echo -e '\n\n\n\n\n'\$(uuidgen)'\n\n\n\n\n'; sleep 2; echo -e 'y\ny\n'; } | ./build-key client &>/dev/null
+server_dir=/etc/openvpn
+if [[ -e /etc/openvpn/server ]]; then
+    server_dir=/etc/openvpn/server
+fi
+
+exists=true
+for x in /etc/openvpn/easy-rsa/keys/{$name.{crt,key},ca.crt}; do
+  if [[ ! -e \$x ]]; then
+     exists=false
+     break
+  fi
+done
+
+if ! \$exists; then
+  cd /etc/openvpn/easy-rsa
+  source vars >/dev/null
+
+  { echo -e '\n\n\n\n\n'$common_name'\n\n\n\n\n'; sleep 2; echo -e 'y\ny\n'; } | ./build-key $name &>/dev/null
+fi
 
 d=\$(mktemp -d)
-cp /etc/openvpn/easy-rsa/keys/ca.crt \
-   /etc/openvpn/update-resolv-conf \
-   /usr/share/doc/openvpn/examples/sample-config-files/client.conf \$d
-mv /etc/openvpn/easy-rsa/keys/client.{crt,key} \$d
+cp /etc/openvpn/easy-rsa/keys/ca.crt \$d/$name-ca.crt
+cp /etc/openvpn/easy-rsa/keys/$name.{crt,key} \$d
 
-sed -i --follow-symlinks "s/^remote .*/remote $host 1194/" \$d/client.conf
+cp \$server_dir/ta.key \$d/$name-ta.key
 
 tar cz -C \$d .
 rm -rf \$d
 EOF
+
+f=/etc/openvpn/client/$name.crt
+if ! $shell "test -s $f"; then
+    # if common name is not unique, you get empty file. and if we didn't silence
+    # build-key, you'd see an error "TXT_DB error number 2"
+    echo "$0: error: $f is empty or otherwise bad. is this common name unique?"
+    exit 1
+fi
+
+$shell "dd of=/etc/openvpn/client/$name.conf" <<EOF
+# From example config, from debian stretch as of 1-2017
+client
+dev tun
+proto udp
+remote $host 1194
+resolv-retry infinite
+nobind
+persist-key
+persist-tun
+ca $name-ca.crt
+cert $name.crt
+key $name.key
+# disabled for better performance
+#comp-lzo
+verb 3
+
+# This script will update local dns
+# to what the server sends, if it sends dns.
+script-security 2
+up $script
+down $script
+
+# matching server config
+cipher AES-256-CBC
+
+
+# example config has the commented line, but this other thing looks stronger,
+# and I've seen it in a vpn provider I trust
+# ns-cert-type server
+remote-cert-tls server
+
+# more resilient when running as nonroot
+persist-key
+
+# See comments in server side configuration.
+# The minimum of the client & server config is what is used by openvpn.
+reneg-sec 432000
+
+tls-auth $name-ta.key 1
+EOF
+
+if [[ $client_host ]] && $custom_script; then
+    $shell "dd of=$script" <$script
+    $shell "chmod +x $script"
+fi
+
+$shell 'cd /etc/openvpn; for f in client/*; do ln -sf $f .; done'