#!/bin/sh
#
#  uAnytun
#
#  uAnytun is a tiny implementation of SATP. Unlike Anytun which is a full
#  featured implementation uAnytun has no support for multiple connections
#  or synchronisation. It is a small single threaded implementation intended
#  to act as a client on small platforms.
#  The secure anycast tunneling protocol (satp) defines a protocol used
#  for communication between any combination of unicast and anycast
#  tunnel endpoints.  It has less protocol overhead than IPSec in Tunnel
#  mode and allows tunneling of every ETHER TYPE protocol (e.g.
#  ethernet, ip, arp ...). satp directly includes cryptography and
#  message authentication based on the methodes used by SRTP.  It is
#  intended to deliver a generic, scaleable and secure solution for
#  tunneling and relaying of packets of any protocol.
#  
#
#  Copyright (C) 2007-2008 Christian Pointner <equinox@anytun.org>
#
#  This file is part of uAnytun.
#
#  uAnytun is free software: you can redistribute it and/or modify
#  it under the terms of the GNU General Public License version 3 as
#  published by the Free Software Foundation.
#
#  uAnytun is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with uAnytun. If not, see <http://www.gnu.org/licenses/>.
#

TARGET=`uname -s`

CFLAGS='-g -O2'
LDFLAGS='-g -Wall -O2'

CRYPTO_LIB='gcrypt'
PASSPHRASE=1
V4_MAPPED=1

PREFIX='/usr/local'
USERNAME='uanytun'
USERHOME='/var/run/uanytun'

print_usage() {
  echo "configure --help                    print this"
  echo "          --target=<TARGET>         build target i.e. Linux (default: autodetect)"
  echo "          --prefix=<PREFIX>         the installation prefix (default: /usr/local)"
  echo "          --username=<USERNAME>     create this user when installing (default: uanytun)"
  echo "          --userhome=<PATH>         the home directory of the user to be created  (default: /var/run/uanytun)"
  echo "          --use-ssl-crypto          use ssl crypto library instead of libgcrypt"
  echo "          --no-crypto               disable crypto at all (only NULL cipher)"
  echo "          --disable-passphrase      disable master key and salt passphrase"
  echo "          --enable-passphrase       enable master key and salt passphrase"
  echo "          --disable-v4-mapped       disable V4-Mapped addresses (this means to disable"
  echo "                                    simultanious use of IPv4 and IPv6)"
  echo "          --enable-v4-mapped        enable V4-Mapped addresses"
}

for arg
do
  case $arg in
  --target=*)
    TARGET=${arg#--target=}
  ;;
  --prefix=*)
    PREFIX=${arg#--prefix=}
  ;;
  --username=*)
    USERNAME=${arg#--username=}
  ;;
  --userhome=*)
    USERHOME=${arg#--userhome=}
  ;;
  --use-ssl-crypto)
    CRYPTO_LIB='ssl'
  ;;
  --no-crypto)
    CRYPTO_LIB='none'
  ;; 
  --disable-passphrase)
    PASSPHRASE=0
  ;;
  --enable-passphrase)
    PASSPHRASE=1
  ;;
  --disable-v4-mapped)
    V4_MAPPED=0 
  ;; 
  --enable-v4-mapped)
    V4_MAPPED=2
  ;; 
  --help)
    print_usage
    exit 0
  ;;
  *)
    echo "Unknown argument: $arg"
    print_usage
    exit 1
  ;;
  esac
done

rm -f include.mk
case $TARGET in 
  Linux)
    rm -f tun.c
    ln -sf linux/tun.c
    echo "loading Linux specific TUN Device"
  ;;
  OpenBSD|FreeBSD|NetBSD)
    rm -f tun.c
    ln -sf bsd/tun.c
    echo "loading BSD specific TUN Device"
    CFLAGS=$CFLAGS' -I/usr/local/include'
    LDFLAGS=$LDFLAGS' -L/usr/local/lib'
    if [ $V4_MAPPED -ne 2 ]; then
      V4_MAPPED=0
    fi
  ;;
  *)
    echo "Plattform not supported"
    exit 1;
  ;;
esac


case $CRYPTO_LIB in
  gcrypt)
    LDFLAGS=$LDFLAGS' -lgcrypt'
    echo "using libgcrypt library"
  ;;
  ssl)
    CFLAGS=$CFLAGS' -DUSE_SSL_CRYPTO'
    LDFLAGS=$LDFLAGS' -lcrypto'
    echo "using ssl crypto library"
  ;;
  none)
    CFLAGS=$CFLAGS' -DNO_CRYPT'
    echo "NO_CRYPT_OBJ = 1" >> include.mk
    echo "disabling crypto"
  ;;
esac

if [ $PASSPHRASE -eq 0 ]; then
  CFLAGS=$CFLAGS' -DNO_PASSPHRASE'
  echo "disabling master key and salt passphrase"
fi

if [ $V4_MAPPED -eq 0 ]; then
  CFLAGS=$CFLAGS' -DNO_V4MAPPED'
  echo "WARNING: disabling V4 mapped addresses, this prevents uanytun from using IPv6 and IPv4 Sockets at the same time"
fi

if [ "x$PREFIX" = "x/usr" ]; then
 ETCDIR=/etc
else
 ETCDIR=$PREFIX/etc
fi

cat >> include.mk <<EOF
# this file was created automatically
# do not edit this file directly 
# use ./configure instead

TARGET := $TARGET
CC := gcc
CFLAGS := $CFLAGS
LDFLAGS := $LDFLAGS

SBINDIR := $PREFIX/sbin
MANDIR := $PREFIX/share/man
ETCDIR := $ETCDIR
USERNAME := $USERNAME
USERHOME := $USERHOME
EOF

exit 0