added inital version (working main lopp with signal handler)

git-svn-id: https://svn.spreadspace.org/tcpproxy/trunk@2 e61f0598-a718-4e21-a8f0-0aadfa62ad6b

14 files changed, 2072 insertions, 0 deletions

diff --git a/src/Makefile b/src/Makefile
new file mode 100644
index 0000000..43c0857
--- /dev/null
+++ b/src/Makefile
@@ -0,0 +1,133 @@
+##
+##  tcpproxy
+##
+##  tcpproxy is a simple tcp connection proxy which combines the 
+##  features of rinetd and 6tunnel. tcpproxy supports IPv4 and 
+##  IPv6 and also supports connections from IPv6 to IPv4 
+##  endpoints and vice versa.
+##  
+##
+##  Copyright (C) 2010-2011 Christian Pointner <equinox@spreadspace.org>
+##                         
+##  This file is part of tcpproxy.
+##
+##  tcpproxy is free software: you can redistribute it and/or modify
+##  it under the terms of the GNU General Public License as published by
+##  the Free Software Foundation, either version 3 of the License, or
+##  any later version.
+##
+##  tcpproxy 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 tcpproxy. If not, see <http://www.gnu.org/licenses/>.
+##
+
+ifneq ($(MAKECMDGOALS),distclean)
+include include.mk
+endif
+
+EXECUTABLE := tcpproxy
+
+C_OBJS := log.o \
+          options.o \
+          string_list.o \
+          sig_handler.o \
+          tcpproxy.o
+
+C_SRCS := $(C_OBJS:%.o=%.c)
+
+.PHONY: clean cleanall distclean manpage install install-bin install-etc install-man uninstall remove purge
+
+all: $(EXECUTABLE)
+
+%.d: %.c
+	@set -e; rm -f $@; \
+  $(CC) -MM $(CFLAGS) $< > $@.$$$$; \
+  sed 's,\($*\)\.o[ :]*,\1.o $@ : ,g' < $@.$$$$ > $@; \
+  rm -f $@.$$$$; echo '(re)building $@'
+
+ifneq ($(MAKECMDGOALS),distclean)
+-include $(C_SRCS:%.c=%.d)
+endif
+
+$(EXECUTABLE): $(C_OBJS)
+	$(CC) $(C_OBJS) -o $@ $(LDFLAGS)
+
+%.o: %.c
+	$(CC) $(CFLAGS) -c $<
+
+strip: $(EXECUTABLE)
+	$(STRIP) -s $(EXECUTABLE)
+
+
+distclean: cleanall
+	find . -name *.o -exec rm -f {} \;
+	find . -name "*.\~*" -exec rm -rf {} \;
+	rm -f include.mk
+	rm -f version.h
+
+clean:
+	rm -f *.o
+	rm -f *.d
+	rm -f *.d.*
+	rm -f $(EXECUTABLE)
+	rm -f $(EXECUTABLE).exe
+
+cleanall: clean
+	$(MAKE) --directory="../doc/" clean
+
+manpage:
+	$(MAKE) --directory="../doc/" manpage
+
+
+INSTALL_TARGETS := install-bin install-etc
+REMOVE_TARGETS := remove-bin remove-etc
+
+ifdef MANDIR
+INSTALL_TARGETS += install-man
+REMOVE_TARGETS += remove-man
+endif
+
+ifdef EXAMPLESDIR
+INSTALL_TARGETS += install-examples
+REMOVE_TARGETS += remove-examples
+endif
+
+install: all $(INSTALL_TARGETS)
+
+install-bin: $(EXECUTABLE)
+	$(INSTALL) -d $(DESTDIR)$(SBINDIR)
+	$(INSTALL) -m 755 $(EXECUTABLE) $(DESTDIR)$(SBINDIR)
+
+install-etc:
+	$(INSTALL) -d $(DESTDIR)$(ETCDIR)/$(EXECUTABLE)
+	@ echo "example configurations can be found at $(EXAMPLESDIR)/$(EXECUTABLE)" > $(DESTDIR)$(ETCDIR)/$(EXECUTABLE)/README
+
+install-examples:
+	$(INSTALL) -d $(DESTDIR)$(EXAMPLESDIR)/$(EXECUTABLE)
+
+install-man: manpage
+	$(INSTALL) -d $(DESTDIR)$(MANDIR)/man8/
+	$(INSTALL) -m 644 ../doc/tcpproxy.8 $(DESTDIR)$(MANDIR)/man8/$(EXECUTABLE).8
+
+uninstall: remove
+
+remove: $(REMOVE_TARGETS)
+
+remove-bin:
+	rm -f $(DESTDIR)$(SBINDIR)/$(EXECUTABLE)
+
+remove-etc:
+	rm -f $(DESTDIR)$(ETCDIR)/init.d/$(EXECUTABLE)
+
+remove-examples:
+	rm -rf $(DESTDIR)$(EXAMPLESDIR)/$(EXECUTABLE)/
+
+remove-man:
+	rm -f $(DESTDIR)$(MANDIR)/man8/$(EXECUTABLE).8
+
+purge: remove
+	rm -rf $(DESTDIR)$(ETCDIR)/$(EXECUTABLE)/
diff --git a/src/configure b/src/configure
new file mode 100755
index 0000000..c87f3c2
--- /dev/null
+++ b/src/configure
@@ -0,0 +1,197 @@
+#!/bin/sh
+# 
+#  tcpproxy
+#
+#  tcpproxy is a simple tcp connection proxy which combines the 
+#  features of rinetd and 6tunnel. tcpproxy supports IPv4 and 
+#  IPv6 and also supports connections from IPv6 to IPv4 
+#  endpoints and vice versa.
+#  
+#
+#  Copyright (C) 2010-2011 Christian Pointner <equinox@spreadspace.org>
+#                         
+#  This file is part of tcpproxy.
+#
+#  tcpproxy is free software: you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation, either version 3 of the License, or
+#  any later version.
+#
+#  tcpproxy 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 tcpproxy. If not, see <http://www.gnu.org/licenses/>.
+#
+
+TARGET=`uname -s`
+EBUILD_COMPAT=0
+
+CFLAGS='-g -O2'
+LDFLAGS='-g -Wall -O2'
+
+PREFIX='/usr/local'
+SBINDIR=''
+ETCDIR=''
+MANDIR=''
+INSTALLMANPAGE=1
+EXAMPLESDIR=''
+INSTALLEXAMPLES=1
+
+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 "          --sbindir=<DIR>           the path to the sbin directory (default: $PREFIX/sbin)"
+  echo "          --sysconfdir=<DIR>        the path to the system configuration directory (default: $PREFIX/etc"
+  echo "          --mandir=<DIR>            the path to the system man pages (default: $PREFIX/share/man)"
+  echo "          --no-manpage              dont't install manpage"
+  echo "          --examplesdir=<DIR>       the path to the examples files (default: $PREFIX/share/examples)"
+  echo "          --no-examples             dont't install example files"
+}
+
+for arg
+do
+  case $arg in
+  --target=*)
+    TARGET=${arg#--target=}
+  ;;
+  --prefix=*)
+    PREFIX=${arg#--prefix=}
+  ;;
+  --sbindir=*)
+    SBINDIR=${arg#--sbindir=}
+  ;;
+  --sysconfdir=*)
+    ETCDIR=${arg#--sysconfdir=}
+  ;;
+  --mandir=*)
+    MANDIR=${arg#--mandir=}
+  ;;
+  --no-manpage)
+    INSTALLMANPAGE=0
+  ;;
+  --examplesdir=*)
+    EXAMPLESDIR=${arg#--examplesdir=}
+  ;;
+  --no-examples)
+    INSTALLEXAMPLES=0
+  ;;
+  --ebuild-compat)
+    EBUILD_COMPAT=1
+  ;;
+  --help)
+    print_usage
+    exit 0
+  ;;
+  *)
+    ERRORS="$ERRORS $arg"
+  ;;
+  esac
+done
+
+if [ -n "$ERRORS" ] && [ $EBUILD_COMPAT -ne 1 ]; then
+  for error in $ERRORS; do
+    echo "Unknown argument: $error"
+  done
+
+  print_usage
+  exit 1
+fi
+
+rm -f version.h
+rm -f include.mk
+case $TARGET in 
+  Linux)
+    LDFLAGS=$LDFLAGS' -ldl'
+  ;;
+  OpenBSD|FreeBSD|NetBSD|GNU/kFreeBSD)
+    CFLAGS=$CFLAGS' -I/usr/local/include'
+    LDFLAGS=$LDFLAGS' -L/usr/local/lib'
+  ;;
+  *)
+    echo "platform not supported"
+    exit 1;
+  ;;
+esac
+
+if [ -z "$SBINDIR" ]; then
+  SBINDIR=$PREFIX/sbin
+fi
+
+if [ -z "$ETCDIR" ]; then
+  ETCDIR=$PREFIX/etc
+fi
+
+if [ -z "$MANDIR" ]; then
+  MANDIR=$PREFIX/share/man
+fi
+
+if [ -z "$EXAMPLESDIR" ]; then
+  EXAMPLESDIR=$PREFIX/share/examples
+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 := $LDFLAGS
+STRIP := strip
+INSTALL := install
+
+PREFIX := '$PREFIX'
+SBINDIR := '$SBINDIR'
+ETCDIR := '$ETCDIR'
+EOF
+
+if [ $INSTALLMANPAGE -eq 1 ]; then
+    echo "MANDIR := '$MANDIR'" >> include.mk
+    echo "installing manpage"
+else
+    echo "not installing manpage"
+fi
+
+if [ $INSTALLEXAMPLES -eq 1 ]; then
+    echo "EXAMPLESDIR := '$EXAMPLESDIR'" >> include.mk
+    echo "installing example files"
+else
+    echo "not installing example files"
+fi
+
+VERSION=`cat ../version`
+if which svn >/dev/null; then
+    SVN_REV=`svn info 2> /dev/null | grep "^Revision: " | awk '{print($2)}'`
+    if [ -n "$SVN_REV" ]; then
+        VERSION="$VERSION (svn$SVN_REV)"
+    fi
+fi
+
+HOSTNAME=`hostname`
+DATE=`date +"%d.%m.%Y %H:%M:%S %Z"`
+
+cat >> version.h <<EOF
+/* 
+ * tcpproxy version info
+ *
+ * this file was created automatically
+ * do not edit this file directly
+ * use ./configure instead
+ */
+
+#ifndef TCPPROXY_version_h_INCLUDED
+#define TCPPROXY_version_h_INCLUDED
+
+#define VERSION_STRING_0 "tcpproxy version $VERSION"
+#define VERSION_STRING_1 "built on $HOSTNAME, $DATE"
+
+#endif
+
+EOF
+
+exit 0
diff --git a/src/daemon.h b/src/daemon.h
new file mode 100644
index 0000000..a910e4a
--- /dev/null
+++ b/src/daemon.h
@@ -0,0 +1,165 @@
+/*
+ *  tcpproxy
+ *
+ *  tcpproxy is a simple tcp connection proxy which combines the 
+ *  features of rinetd and 6tunnel. tcpproxy supports IPv4 and 
+ *  IPv6 and also supports connections from IPv6 to IPv4 
+ *  endpoints and vice versa.
+ *  
+ *
+ *  Copyright (C) 2010-2011 Christian Pointner <equinox@spreadspace.org>
+ *                         
+ *  This file is part of tcpproxy.
+ *
+ *  tcpproxy is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  any later version.
+ *
+ *  tcpproxy 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 tcpproxy. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef TCPPROXY_daemon_h_INCLUDED
+#define TCPPROXY_daemon_h_INCLUDED
+
+#include <poll.h>
+#include <fcntl.h>
+#include <pwd.h>
+#include <grp.h>
+#include <sys/wait.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+struct priv_info_struct {
+  struct passwd* pw_;
+  struct group* gr_;
+};
+typedef struct priv_info_struct priv_info_t;
+
+int priv_init(priv_info_t* priv, const char* username, const char* groupname)
+{
+  if(!priv)
+    return -1;
+
+  priv->pw_ = NULL;
+  priv->gr_ = NULL;
+
+  priv->pw_ = getpwnam(username);
+  if(!priv->pw_) {
+    log_printf(ERROR, "unkown user %s", username);
+    return -1;
+  }
+
+  if(groupname)
+    priv->gr_ = getgrnam(groupname);
+  else
+    priv->gr_ = getgrgid(priv->pw_->pw_gid);
+
+  if(!priv->gr_) {
+    log_printf(ERROR, "unkown group %s", groupname);
+    return -1;
+  }
+
+  return 0;
+}
+
+int priv_drop(priv_info_t* priv)
+{
+  if(!priv || !priv->pw_ || !priv->gr_) {
+    log_printf(ERROR, "privileges not initialized properly");
+    return -1;
+  }
+
+  if(setgid(priv->gr_->gr_gid))  {
+    log_printf(ERROR, "setgid('%s') failed: %s", priv->gr_->gr_name, strerror(errno));
+    return -1;
+  }
+
+  gid_t gr_list[1];
+  gr_list[0] = priv->gr_->gr_gid;
+  if(setgroups (1, gr_list)) {
+    log_printf(ERROR, "setgroups(['%s']) failed: %s", priv->gr_->gr_name, strerror(errno));
+    return -1;
+  }
+
+  if(setuid(priv->pw_->pw_uid)) {
+    log_printf(ERROR, "setuid('%s') failed: %s", priv->pw_->pw_name, strerror(errno));
+    return -1;
+  }
+
+  log_printf(NOTICE, "dropped privileges to %s:%s", priv->pw_->pw_name, priv->gr_->gr_name);
+  return 0;
+}
+
+
+int do_chroot(const char* chrootdir)
+{
+  if(getuid() != 0) {
+    log_printf(ERROR, "this program has to be run as root in order to run in a chroot");
+    return -1;
+  }
+
+  if(chroot(chrootdir)) {
+    log_printf(ERROR, "can't chroot to %s: %s", chrootdir, strerror(errno));
+    return -1;
+  }
+  log_printf(NOTICE, "we are in chroot jail (%s) now", chrootdir);
+  if(chdir("/")) {
+    log_printf(ERROR, "can't change to /: %s", strerror(errno));
+    return -1;
+  }
+}
+
+void daemonize()
+{
+  pid_t pid;
+
+  pid = fork();
+  if(pid < 0) {
+    log_printf(ERROR, "daemonizing failed at fork(): %s, exitting", strerror(errno));
+    exit(-1);
+  }
+  if(pid) exit(0);
+
+  umask(0);
+
+  if(setsid() < 0) {
+    log_printf(ERROR, "daemonizing failed at setsid(): %s, exitting", strerror(errno));
+    exit(-1);
+  }
+
+  pid = fork();
+  if(pid < 0) {
+    log_printf(ERROR, "daemonizing failed at fork(): %s, exitting", strerror(errno));
+    exit(-1);
+  }
+  if(pid) exit(0);
+
+  if ((chdir("/")) < 0) {
+    log_printf(ERROR, "daemonizing failed at chdir(): %s, exitting", strerror(errno));
+    exit(-1);
+  }
+
+  int fd;
+  for (fd=0;fd<=2;fd++) // close all file descriptors
+    close(fd);
+  fd = open("/dev/null",O_RDWR);        // stdin
+  if(fd == -1)
+    log_printf(WARNING, "can't open stdin (chroot and no link to /dev/null?)");
+  else {
+    if(dup(fd) == -1)   // stdout
+      log_printf(WARNING, "can't open stdout");
+    if(dup(fd) == -1)   // stderr
+      log_printf(WARNING, "can't open stderr");
+  }
+  umask(027);
+}
+
+#endif
+
diff --git a/src/datatypes.h b/src/datatypes.h
new file mode 100644
index 0000000..deac84d
--- /dev/null
+++ b/src/datatypes.h
@@ -0,0 +1,39 @@
+/*
+ *  tcpproxy
+ *
+ *  tcpproxy is a simple tcp connection proxy which combines the 
+ *  features of rinetd and 6tunnel. tcpproxy supports IPv4 and 
+ *  IPv6 and also supports connections from IPv6 to IPv4 
+ *  endpoints and vice versa.
+ *  
+ *
+ *  Copyright (C) 2010-2011 Christian Pointner <equinox@spreadspace.org>
+ *                         
+ *  This file is part of tcpproxy.
+ *
+ *  tcpproxy is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  any later version.
+ *
+ *  tcpproxy 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 tcpproxy. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef TCPPROXY_datatypes_h_INCLUDED
+#define TCPPROXY_datatypes_h_INCLUDED
+
+#include <stdint.h>
+
+struct buffer_struct {
+  uint32_t length_;
+  uint8_t* buf_;
+};
+typedef struct buffer_struct buffer_t;
+
+#endif
diff --git a/src/log.c b/src/log.c
new file mode 100644
index 0000000..c3aa346
--- /dev/null
+++ b/src/log.c
@@ -0,0 +1,252 @@
+/*
+ *  tcpproxy
+ *
+ *  tcpproxy is a simple tcp connection proxy which combines the 
+ *  features of rinetd and 6tunnel. tcpproxy supports IPv4 and 
+ *  IPv6 and also supports connections from IPv6 to IPv4 
+ *  endpoints and vice versa.
+ *  
+ *
+ *  Copyright (C) 2010-2011 Christian Pointner <equinox@spreadspace.org>
+ *                         
+ *  This file is part of tcpproxy.
+ *
+ *  tcpproxy is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  any later version.
+ *
+ *  tcpproxy 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 tcpproxy. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "datatypes.h"
+
+#include <ctype.h>
+#include <string.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+#define SYSLOG_NAMES
+#include <syslog.h>
+
+#include "log.h"
+
+log_t stdlog;
+
+#include "log_targets.h"
+
+const char* log_prio_to_string(log_prio_t prio)
+{
+  switch(prio) {
+  case ERROR: return "ERROR";
+  case WARNING: return "WARNING";
+  case NOTICE: return "NOTICE";
+  case INFO: return "INFO";
+  case DEBUG: return "DEBUG";
+  }
+  return "UNKNOWN";
+}
+
+log_target_type_t log_target_parse_type(const char* conf)
+{
+  if(!conf)
+    return TARGET_UNKNOWN;
+
+  if(!strncmp(conf, "syslog", 6)) return TARGET_SYSLOG;
+  if(!strncmp(conf, "file", 4)) return TARGET_FILE;
+  if(!strncmp(conf, "stdout", 6)) return TARGET_STDOUT;
+  if(!strncmp(conf, "stderr", 6)) return TARGET_STDERR;
+
+  return TARGET_UNKNOWN;
+}
+
+int log_targets_target_exists(log_targets_t* targets, log_target_type_t type)
+{
+  if(!targets && !targets->first_)
+    return 0;
+
+  log_target_t* tmp = targets->first_;
+  while(tmp) {
+    if(tmp->type_ == type)
+      return 1;
+    tmp = tmp->next_;
+  }  
+  return 0;
+}
+
+int log_targets_add(log_targets_t* targets, const char* conf)
+{
+  if(!targets)
+    return -1;
+
+  log_target_t* new_target = NULL;
+  int duplicates_allowed = 0;
+  switch(log_target_parse_type(conf)) {
+  case TARGET_SYSLOG: new_target = log_target_syslog_new(); break;
+  case TARGET_FILE: new_target = log_target_file_new(); duplicates_allowed = 1; break;
+  case TARGET_STDOUT: new_target = log_target_stdout_new(); break;
+  case TARGET_STDERR: new_target = log_target_stderr_new(); break;
+  default: return -3;
+  }
+  if(!new_target)
+    return -2;
+
+  if(!duplicates_allowed && log_targets_target_exists(targets, new_target->type_)) {
+    free(new_target);
+    return -4;
+  }
+
+  const char* prioptr = strchr(conf, ':');
+  if(!prioptr || prioptr[1] == 0) {
+    free(new_target);
+    return -1;
+  }
+  prioptr++;
+  if(!isdigit(prioptr[0]) || (prioptr[1] != 0 && prioptr[1] != ',')) {
+    free(new_target);
+    return -1;
+  }
+  new_target->max_prio_ = prioptr[0] - '0';
+  if(new_target->max_prio_ > 0)
+    new_target->enabled_ = 1;
+
+  if(new_target->init != NULL) {
+    const char* confptr = NULL;
+    if(prioptr[1] != 0)
+      confptr = prioptr+2;
+
+    int ret = (*new_target->init)(new_target, confptr);
+    if(ret) {
+      free(new_target);
+      return ret;
+    }
+  }
+
+  if(new_target->open != NULL)
+    (*new_target->open)(new_target);
+
+
+  if(!targets->first_) {
+    targets->first_ = new_target;
+  }
+  else {
+    log_target_t* tmp = targets->first_;
+    while(tmp->next_)
+      tmp = tmp->next_;
+    
+    tmp->next_ = new_target;
+  }
+  return 0;
+}
+
+void log_targets_log(log_targets_t* targets, log_prio_t prio, const char* msg)
+{
+  if(!targets)
+    return;
+
+  log_target_t* tmp = targets->first_;
+  while(tmp) {
+    if(tmp->log != NULL && tmp->enabled_ && tmp->max_prio_ >= prio)
+      (*tmp->log)(tmp, prio, msg);
+
+    tmp = tmp->next_;
+  }
+}
+
+void log_targets_clear(log_targets_t* targets)
+{
+  if(!targets)
+    return;
+
+  while(targets->first_) {
+    log_target_t* tmp = targets->first_;
+    targets->first_ = tmp->next_;
+    if(tmp->close != NULL)
+      (*tmp->close)(tmp);
+    if(tmp->clear != NULL)
+      (*tmp->clear)(tmp);
+    free(tmp);
+  }
+}
+
+
+void log_init()
+{
+  stdlog.max_prio_ = 0;
+  stdlog.targets_.first_ = NULL;
+}
+
+void log_close()
+{
+  log_targets_clear(&stdlog.targets_);
+}
+
+void update_max_prio()
+{
+  log_target_t* tmp = stdlog.targets_.first_;
+  while(tmp) {
+    if(tmp->enabled_ && tmp->max_prio_ > stdlog.max_prio_)
+      stdlog.max_prio_ = tmp->max_prio_;
+
+    tmp = tmp->next_;
+  }
+}
+
+int log_add_target(const char* conf)
+{
+  if(!conf)
+    return -1;
+
+  int ret = log_targets_add(&stdlog.targets_, conf);
+  if(!ret) update_max_prio();
+  return ret;
+}
+
+void log_printf(log_prio_t prio, const char* fmt, ...)
+{
+  if(stdlog.max_prio_ < prio)
+    return;
+
+  static char msg[MSG_LENGTH_MAX];
+  va_list args;
+
+  va_start(args, fmt);
+  vsnprintf(msg, MSG_LENGTH_MAX, fmt, args);
+  va_end(args);
+
+  log_targets_log(&stdlog.targets_, prio, msg);
+}
+
+void log_print_hex_dump(log_prio_t prio, const uint8_t* buf, uint32_t len)
+{
+  if(stdlog.max_prio_ < prio)
+    return;
+
+  static char msg[MSG_LENGTH_MAX];
+
+  if(!buf) {
+    snprintf(msg, MSG_LENGTH_MAX, "(NULL)");
+  }
+  else {
+    uint32_t i;
+    int offset = snprintf(msg, MSG_LENGTH_MAX, "dump(%d): ", len);
+    if(offset < 0)
+      return;
+    uint8_t* ptr = &msg[offset];
+    
+    for(i=0; i < len; i++) {
+      if(((i+1)*3) >= (MSG_LENGTH_MAX - offset))
+        break;
+      snprintf(ptr, 3, "%02X ", buf[i]);
+      ptr+=3;
+    }
+  }
+  log_targets_log(&stdlog.targets_, prio, msg);
+}
diff --git a/src/log.h b/src/log.h
new file mode 100644
index 0000000..cde20ac
--- /dev/null
+++ b/src/log.h
@@ -0,0 +1,82 @@
+/*
+ *  tcpproxy
+ *
+ *  tcpproxy is a simple tcp connection proxy which combines the 
+ *  features of rinetd and 6tunnel. tcpproxy supports IPv4 and 
+ *  IPv6 and also supports connections from IPv6 to IPv4 
+ *  endpoints and vice versa.
+ *  
+ *
+ *  Copyright (C) 2010-2011 Christian Pointner <equinox@spreadspace.org>
+ *                         
+ *  This file is part of tcpproxy.
+ *
+ *  tcpproxy is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  any later version.
+ *
+ *  tcpproxy 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 tcpproxy. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef TCPPROXY_log_h_INCLUDED
+#define TCPPROXY_log_h_INCLUDED
+
+#define MSG_LENGTH_MAX 1024
+
+enum log_prio_enum { ERROR = 1, WARNING = 2, NOTICE = 3,
+                     INFO = 4, DEBUG = 5 };
+typedef enum log_prio_enum log_prio_t;
+
+const char* log_prio_to_string(log_prio_t prio);
+
+enum log_target_type_enum { TARGET_SYSLOG , TARGET_STDOUT, TARGET_STDERR, TARGET_FILE , TARGET_UNKNOWN };
+typedef enum log_target_type_enum log_target_type_t;
+
+struct log_target_struct {
+  log_target_type_t type_;
+  int (*init)(struct log_target_struct* self, const char* conf);
+  void (*open)(struct log_target_struct* self);
+  void (*log)(struct log_target_struct* self, log_prio_t prio, const char* msg);
+  void (*close)(struct log_target_struct* self);
+  void (*clear)(struct log_target_struct* self);
+  int opened_;
+  int enabled_;
+  log_prio_t max_prio_;
+  void* param_;
+  struct log_target_struct* next_;
+};
+typedef struct log_target_struct log_target_t;
+
+
+struct log_targets_struct {
+  log_target_t* first_;
+};
+typedef struct log_targets_struct log_targets_t;
+
+int log_targets_target_exists(log_targets_t* targets, log_target_type_t type);
+int log_targets_add(log_targets_t* targets, const char* conf);
+void log_targets_log(log_targets_t* targets, log_prio_t prio, const char* msg);
+void log_targets_clear(log_targets_t* targets);
+
+
+struct log_struct {
+  log_prio_t max_prio_;
+  log_targets_t targets_;
+};
+typedef struct log_struct log_t;
+
+void log_init();
+void log_close();
+void update_max_prio();
+int log_add_target(const char* conf);
+void log_printf(log_prio_t prio, const char* fmt, ...);
+void log_print_hex_dump(log_prio_t prio, const uint8_t* buf, uint32_t len);
+
+#endif
diff --git a/src/log_targets.h b/src/log_targets.h
new file mode 100644
index 0000000..5ee3a39
--- /dev/null
+++ b/src/log_targets.h
@@ -0,0 +1,356 @@
+/*
+ *  tcpproxy
+ *
+ *  tcpproxy is a simple tcp connection proxy which combines the 
+ *  features of rinetd and 6tunnel. tcpproxy supports IPv4 and 
+ *  IPv6 and also supports connections from IPv6 to IPv4 
+ *  endpoints and vice versa.
+ *  
+ *
+ *  Copyright (C) 2010-2011 Christian Pointner <equinox@spreadspace.org>
+ *                         
+ *  This file is part of tcpproxy.
+ *
+ *  tcpproxy is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  any later version.
+ *
+ *  tcpproxy 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 tcpproxy. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef TCPPROXY_log_targets_h_INCLUDED
+#define TCPPROXY_log_targets_h_INCLUDED
+
+#include <time.h>
+
+static char* get_time_formatted()
+{
+  char* time_string;
+  time_t t = time(NULL);
+  if(t < 0) 
+    time_string = "<time read error>";
+  else {
+    time_string = ctime(&t);
+    if(!time_string)
+      time_string = "<time format error>";
+    else {
+      char* newline = strchr(time_string, '\n');
+      if(newline)
+        newline[0] = 0;
+    }
+  }
+  return time_string;
+}
+
+#ifndef WINVER
+enum syslog_facility_enum { USER = LOG_USER, MAIL = LOG_MAIL,
+                            DAEMON = LOG_DAEMON, AUTH = LOG_AUTH,
+                            SYSLOG = LOG_SYSLOG, LPR = LOG_LPR,
+                            NEWS = LOG_NEWS, UUCP = LOG_UUCP,
+                            CRON = LOG_CRON, AUTHPRIV = LOG_AUTHPRIV,
+                            FTP = LOG_FTP, LOCAL0 = LOG_LOCAL0,
+                            LOCAL1 = LOG_LOCAL1, LOCAL2 = LOG_LOCAL2,
+                            LOCAL3 = LOG_LOCAL3, LOCAL4 = LOG_LOCAL4,
+                            LOCAL5 = LOG_LOCAL5, LOCAL6 = LOG_LOCAL6,
+                            LOCAL7 = LOG_LOCAL7 };
+typedef enum syslog_facility_enum syslog_facility_t;
+
+struct log_target_syslog_param_struct {
+  char* logname_;
+  syslog_facility_t facility_;
+};
+typedef struct log_target_syslog_param_struct log_target_syslog_param_t;
+
+int log_target_syslog_init(log_target_t* self, const char* conf)
+{
+  if(!self || (conf && conf[0] == 0))
+    return -1;
+  
+  self->param_ = malloc(sizeof(log_target_syslog_param_t));
+  if(!self->param_)
+    return -2;
+
+  char* logname;
+  const char* end = NULL;
+  if(!conf)
+    logname = strdup("tcpproxy");
+  else {
+    end = strchr(conf, ',');
+    if(end) {
+      size_t len = (size_t)(end - conf);
+      if(!len) {
+        free(self->param_);
+        return -1;
+      }  
+      logname = malloc(len+1);
+      if(logname) {
+        strncpy(logname, conf, len);
+        logname[len] = 0;
+      }
+    }
+    else
+      logname = strdup(conf);
+  }
+
+  if(!logname) {
+    free(self->param_);
+    return -2;
+  }
+  ((log_target_syslog_param_t*)(self->param_))->logname_ = logname;
+
+  if(!end) {
+    ((log_target_syslog_param_t*)(self->param_))->facility_ = DAEMON;
+    return 0;
+  }
+  
+  if(end[1] == 0 || end[1] == ',') {
+    free(logname);
+    free(self->param_);
+    return -1;
+  }
+    
+  const char* start = end + 1;
+  end = strchr(start, ',');
+  int i;
+  for(i=0;;++i) {
+    if(facilitynames[i].c_name == NULL) {
+      free(logname);
+      free(self->param_);
+      return -1;
+    }
+
+    if(( end && !strncmp(start, facilitynames[i].c_name, (size_t)(end - start)) && facilitynames[i].c_name[(size_t)(end-start)] == 0) ||
+       (!end && !strcmp(start, facilitynames[i].c_name))) {
+        ((log_target_syslog_param_t*)(self->param_))->facility_ = facilitynames[i].c_val;
+        break;
+    }
+  }
+
+  return 0;
+}
+
+void log_target_syslog_open(log_target_t* self)
+{
+  if(!self || !self->param_)
+    return;
+
+  openlog(((log_target_syslog_param_t*)(self->param_))->logname_, LOG_PID, ((log_target_syslog_param_t*)(self->param_))->facility_);
+  self->opened_ = 1;
+}
+
+void log_target_syslog_log(log_target_t* self, log_prio_t prio, const char* msg)
+{
+  if(!self || !self->param_ || !self->opened_)
+    return;
+
+  syslog((prio + 2) | ((log_target_syslog_param_t*)(self->param_))->facility_, "%s", msg);  
+}
+
+void log_target_syslog_close(log_target_t* self)
+{
+  closelog();
+  self->opened_ = 0;
+}
+
+void log_target_syslog_clear(log_target_t* self)
+{
+  if(!self || !self->param_)
+    return;
+
+  if(((log_target_syslog_param_t*)(self->param_))->logname_)
+    free(((log_target_syslog_param_t*)(self->param_))->logname_);
+
+  free(self->param_);
+}
+
+log_target_t* log_target_syslog_new()
+{
+  log_target_t* tmp = malloc(sizeof(log_target_t));
+  if(!tmp)
+    return NULL;
+
+  tmp->type_ = TARGET_SYSLOG;
+  tmp->init = &log_target_syslog_init;
+  tmp->open = &log_target_syslog_open;
+  tmp->log = &log_target_syslog_log;
+  tmp->close = &log_target_syslog_close;
+  tmp->clear = &log_target_syslog_clear;
+  tmp->opened_ = 0;
+  tmp->enabled_ = 0;
+  tmp->max_prio_ = NOTICE;
+  tmp->param_ = NULL;
+  tmp->next_ = NULL;
+
+  return tmp;
+}
+#endif
+
+struct log_target_file_param_struct {
+  char* logfilename_;
+  FILE* file_;
+};
+typedef struct log_target_file_param_struct log_target_file_param_t;
+
+int log_target_file_init(log_target_t* self, const char* conf)
+{
+  if(!self || (conf && conf[0] == 0))
+    return -1;
+  
+  self->param_ = malloc(sizeof(log_target_file_param_t));
+  if(!self->param_)
+    return -2;
+
+  char* logfilename;
+  if(!conf)
+    logfilename = strdup("tcpproxy.log");
+  else {
+    const char* end = strchr(conf, ',');
+    if(end) {
+      size_t len = (size_t)(end - conf);
+      if(!len) {
+        free(self->param_);
+        return -1;
+      }  
+      logfilename = malloc(len+1);
+      if(logfilename) {
+        strncpy(logfilename, conf, len);
+        logfilename[len] = 0;
+      }
+    }
+    else
+      logfilename = strdup(conf);
+  }
+
+  if(!logfilename) {
+    free(self->param_);
+    return -2;
+  }
+  ((log_target_file_param_t*)(self->param_))->logfilename_ = logfilename;
+  ((log_target_file_param_t*)(self->param_))->file_ = NULL;
+
+  return 0;
+}
+
+void log_target_file_open(log_target_t* self)
+{
+  if(!self || !self->param_)
+    return;
+
+  ((log_target_file_param_t*)(self->param_))->file_ = fopen(((log_target_file_param_t*)(self->param_))->logfilename_, "w");
+  if(((log_target_file_param_t*)(self->param_))->file_)
+    self->opened_ = 1;
+}
+
+void log_target_file_log(log_target_t* self, log_prio_t prio, const char* msg)
+{
+  if(!self || !self->param_ || !self->opened_)
+    return;
+
+  fprintf(((log_target_file_param_t*)(self->param_))->file_, "%s %s: %s\n", get_time_formatted(), log_prio_to_string(prio), msg);
+  fflush(((log_target_file_param_t*)(self->param_))->file_);
+}
+
+void log_target_file_close(log_target_t* self)
+{
+  if(!self || !self->param_)
+    return;
+
+  fclose(((log_target_file_param_t*)(self->param_))->file_);
+  self->opened_ = 0;
+}
+
+void log_target_file_clear(log_target_t* self)
+{
+  if(!self || !self->param_)
+    return;
+
+  if(((log_target_file_param_t*)(self->param_))->logfilename_)
+    free(((log_target_file_param_t*)(self->param_))->logfilename_);
+
+  free(self->param_);
+}
+
+
+log_target_t* log_target_file_new()
+{
+  log_target_t* tmp = malloc(sizeof(log_target_t));
+  if(!tmp)
+    return NULL;
+
+  tmp->type_ = TARGET_FILE;
+  tmp->init = &log_target_file_init;
+  tmp->open = &log_target_file_open;
+  tmp->log = &log_target_file_log;
+  tmp->close = &log_target_file_close;
+  tmp->clear = &log_target_file_clear;
+  tmp->opened_ = 0;
+  tmp->enabled_ = 0;
+  tmp->max_prio_ = NOTICE;
+  tmp->param_ = NULL;
+  tmp->next_ = NULL;
+
+  return tmp;
+}
+
+
+void log_target_stdout_log(log_target_t* self, log_prio_t prio, const char* msg)
+{
+  printf("%s %s: %s\n", get_time_formatted(), log_prio_to_string(prio), msg);
+}
+
+log_target_t* log_target_stdout_new()
+{
+  log_target_t* tmp = malloc(sizeof(log_target_t));
+  if(!tmp)
+    return NULL;
+
+  tmp->type_ = TARGET_STDOUT;
+  tmp->init = NULL;
+  tmp->open = NULL;
+  tmp->log = &log_target_stdout_log;
+  tmp->close = NULL;
+  tmp->clear = NULL;
+  tmp->opened_ = 0;
+  tmp->enabled_ = 0;
+  tmp->max_prio_ = NOTICE;
+  tmp->param_ = NULL;
+  tmp->next_ = NULL;
+
+  return tmp;
+}
+
+
+void log_target_stderr_log(log_target_t* self, log_prio_t prio, const char* msg)
+{
+  fprintf(stderr, "%s %s: %s\n", get_time_formatted(), log_prio_to_string(prio), msg);
+}
+
+log_target_t* log_target_stderr_new()
+{
+  log_target_t* tmp = malloc(sizeof(log_target_t));
+  if(!tmp)
+    return NULL;
+
+  tmp->type_ = TARGET_STDERR;
+  tmp->init = NULL;
+  tmp->open = NULL;
+  tmp->log = &log_target_stderr_log;
+  tmp->close = NULL;
+  tmp->clear = NULL;
+  tmp->opened_ = 0;
+  tmp->enabled_ = 0;
+  tmp->max_prio_ = NOTICE;
+  tmp->param_ = NULL;
+  tmp->next_ = NULL;
+
+  return tmp;
+}
+
+#endif
diff --git a/src/options.c b/src/options.c
new file mode 100644
index 0000000..76b93e3
--- /dev/null
+++ b/src/options.c
@@ -0,0 +1,273 @@
+/*
+ *  tcpproxy
+ *
+ *  tcpproxy is a simple tcp connection proxy which combines the 
+ *  features of rinetd and 6tunnel. tcpproxy supports IPv4 and 
+ *  IPv6 and also supports connections from IPv6 to IPv4 
+ *  endpoints and vice versa.
+ *  
+ *
+ *  Copyright (C) 2010-2011 Christian Pointner <equinox@spreadspace.org>
+ *                         
+ *  This file is part of tcpproxy.
+ *
+ *  tcpproxy is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  any later version.
+ *
+ *  tcpproxy 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 tcpproxy. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "datatypes.h"
+#include "version.h"
+
+#include "options.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <ctype.h>
+
+#define PARSE_BOOL_PARAM(SHORT, LONG, VALUE)             \
+    else if(!strcmp(str,SHORT) || !strcmp(str,LONG))     \
+      VALUE = 1;
+
+#define PARSE_INVERSE_BOOL_PARAM(SHORT, LONG, VALUE)     \
+    else if(!strcmp(str,SHORT) || !strcmp(str,LONG))     \
+      VALUE = 0;
+
+#define PARSE_INT_PARAM(SHORT, LONG, VALUE)              \
+    else if(!strcmp(str,SHORT) || !strcmp(str,LONG))     \
+    {                                                    \
+      if(argc < 1)                                       \
+        return i;                                        \
+      VALUE = atoi(argv[i+1]);                           \
+      argc--;                                            \
+      i++;                                               \
+    }
+
+#define PARSE_STRING_PARAM(SHORT, LONG, VALUE)           \
+    else if(!strcmp(str,SHORT) || !strcmp(str,LONG))     \
+    {                                                    \
+      if(argc < 1 || argv[i+1][0] == '-')                \
+        return i;                                        \
+      if(VALUE) free(VALUE);                             \
+      VALUE = strdup(argv[i+1]);                         \
+      if(!VALUE)                                         \
+        return -2;                                       \
+      argc--;                                            \
+      i++;                                               \
+    }
+
+#define PARSE_STRING_PARAM_SEC(SHORT, LONG, VALUE)       \
+    else if(!strcmp(str,SHORT) || !strcmp(str,LONG))     \
+    {                                                    \
+      if(argc < 1 || argv[i+1][0] == '-')                \
+        return i;                                        \
+      if(VALUE) free(VALUE);                             \
+      VALUE = strdup(argv[i+1]);                         \
+      if(!VALUE)                                         \
+        return -2;                                       \
+      size_t j;                                          \
+      for(j=0; j < strlen(argv[i+1]); ++j)               \
+        argv[i+1][j] = '#';                              \
+      argc--;                                            \
+      i++;                                               \
+    }
+
+#define PARSE_HEXSTRING_PARAM_SEC(SHORT, LONG, VALUE)    \
+    else if(!strcmp(str,SHORT) || !strcmp(str,LONG))     \
+    {                                                    \
+      if(argc < 1 || argv[i+1][0] == '-')                \
+        return i;                                        \
+      int ret;                                           \
+      ret = options_parse_hex_string(argv[i+1], &VALUE); \
+      if(ret > 0)                                        \
+        return i+1;                                      \
+      else if(ret < 0)                                   \
+        return ret;                                      \
+      size_t j;                                          \
+      for(j=0; j < strlen(argv[i+1]); ++j)               \
+        argv[i+1][j] = '#';                              \
+      argc--;                                            \
+      i++;                                               \
+    }
+
+#define PARSE_STRING_LIST(SHORT, LONG, LIST)             \
+    else if(!strcmp(str,SHORT) || !strcmp(str,LONG))     \
+    {                                                    \
+      if(argc < 1 || argv[i+1][0] == '-')                \
+        return i;                                        \
+      int ret = string_list_add(&LIST, argv[i+1]);       \
+      if(ret == -2)                                      \
+        return ret;                                      \
+      else if(ret)                                       \
+        return i+1;                                      \
+      argc--;                                            \
+      i++;                                               \
+    }
+
+int options_parse_hex_string(const char* hex, buffer_t* buffer)
+{
+  if(!hex || !buffer)
+    return -1;
+
+  uint32_t hex_len = strlen(hex);
+  if(hex_len%2)
+    return 1;
+
+  if(buffer->buf_) 
+    free(buffer->buf_);
+  
+  buffer->length_ = hex_len/2;
+  buffer->buf_ = malloc(buffer->length_);
+  if(!buffer->buf_) {
+    buffer->length_ = 0;
+    return -2;
+  }
+
+  const char* ptr = hex;
+  int i;
+  for(i=0;i<buffer->length_;++i) {
+    uint32_t tmp;
+    sscanf(ptr, "%2X", &tmp);
+    buffer->buf_[i] = (uint8_t)tmp;
+    ptr += 2;
+  }
+
+  return 0;
+}
+
+
+int options_parse(options_t* opt, int argc, char* argv[])
+{
+  if(!opt)
+    return -1;
+
+  options_default(opt);
+
+  if(opt->progname_)
+    free(opt->progname_);
+  opt->progname_ = strdup(argv[0]);
+  if(!opt->progname_)
+    return -2;
+
+  argc--;
+
+  int i;
+  for(i=1; argc > 0; ++i)
+  {
+    char* str = argv[i];
+    argc--;
+
+    if(!strcmp(str,"-h") || !strcmp(str,"--help"))
+      return -1;
+    else if(!strcmp(str,"-v") || !strcmp(str,"--version"))
+      return -3;
+    PARSE_INVERSE_BOOL_PARAM("-D","--nodaemonize", opt->daemonize_)
+    PARSE_STRING_PARAM("-u","--username", opt->username_)
+    PARSE_STRING_PARAM("-g","--groupname", opt->groupname_)
+    PARSE_STRING_PARAM("-C","--chroot", opt->chroot_dir_)
+    PARSE_STRING_PARAM("-P","--write-pid", opt->pid_file_)
+    PARSE_STRING_LIST("-L","--log", opt->log_targets_)
+    PARSE_BOOL_PARAM("-U", "--debug", opt->debug_)
+    else 
+      return i;
+  }
+
+  if(opt->debug_) {
+    string_list_add(&opt->log_targets_, "stdout:5");
+    opt->daemonize_ = 0;
+  }
+
+  if(!opt->log_targets_.first_) {
+    string_list_add(&opt->log_targets_, "syslog:3,tcpproxy,daemon");
+  }
+
+  return 0;
+}
+
+void options_parse_post(options_t* opt)
+{
+  if(!opt)
+    return;
+
+      // nothing yet
+}
+
+void options_default(options_t* opt)
+{
+  if(!opt)
+    return;
+
+  opt->progname_ = strdup("tcpproxy");
+  opt->daemonize_ = 1;
+  opt->username_ = NULL;
+  opt->groupname_ = NULL;
+  opt->chroot_dir_ = NULL;
+  opt->pid_file_ = NULL;
+  string_list_init(&opt->log_targets_);
+  opt->debug_ = 0;
+}
+
+void options_clear(options_t* opt)
+{
+  if(!opt)
+    return;
+
+  if(opt->progname_)
+    free(opt->progname_);
+  if(opt->username_)
+    free(opt->username_);
+  if(opt->groupname_)
+    free(opt->groupname_);
+  if(opt->chroot_dir_)
+    free(opt->chroot_dir_);
+  if(opt->pid_file_)
+    free(opt->pid_file_);
+  string_list_clear(&opt->log_targets_);
+}
+
+void options_print_usage()
+{
+  printf("USAGE:\n");
+  printf("tcpproxy [-h|--help]                         prints this...\n");
+  printf("         [-v|--version]                      print version info and exit\n");
+  printf("         [-D|--nodaemonize]                  don't run in background\n");
+  printf("         [-u|--username] <username>          change to this user\n");
+  printf("         [-g|--groupname] <groupname>        change to this group\n");
+  printf("         [-C|--chroot] <path>                chroot to this directory\n");
+  printf("         [-P|--write-pid] <path>             write pid to this file\n");
+  printf("         [-L|--log] <target>:<level>[,<param1>[,<param2>..]]\n");
+  printf("                                             add a log target, can be invoked several times\n");
+  printf("         [-U|--debug]                        don't daemonize and log to stdout with maximum log level\n");
+}
+
+void options_print_version()
+{
+  printf("%s\n", VERSION_STRING_0);
+  printf("%s\n", VERSION_STRING_1);
+}
+
+void options_print(options_t* opt)
+{
+  if(!opt)
+    return;
+
+  printf("progname: '%s'\n", opt->progname_);
+  printf("daemonize: %d\n", opt->daemonize_);
+  printf("username: '%s'\n", opt->username_);
+  printf("groupname: '%s'\n", opt->groupname_);
+  printf("chroot_dir: '%s'\n", opt->chroot_dir_);
+  printf("pid_file: '%s'\n", opt->pid_file_);
+  printf("log_targets: \n");
+  string_list_print(&opt->log_targets_, "  '", "'\n");
+  printf("debug: %s\n", !opt->debug_ ? "false" : "true");
+}
diff --git a/src/options.h b/src/options.h
new file mode 100644
index 0000000..e3a980d
--- /dev/null
+++ b/src/options.h
@@ -0,0 +1,56 @@
+/*
+ *  tcpproxy
+ *
+ *  tcpproxy is a simple tcp connection proxy which combines the 
+ *  features of rinetd and 6tunnel. tcpproxy supports IPv4 and 
+ *  IPv6 and also supports connections from IPv6 to IPv4 
+ *  endpoints and vice versa.
+ *  
+ *
+ *  Copyright (C) 2010-2011 Christian Pointner <equinox@spreadspace.org>
+ *                         
+ *  This file is part of tcpproxy.
+ *
+ *  tcpproxy is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  any later version.
+ *
+ *  tcpproxy 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 tcpproxy. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef TCPPROXY_options_h_INCLUDED
+#define TCPPROXY_options_h_INCLUDED
+
+#include "string_list.h"
+#include "datatypes.h"
+
+struct options_struct {
+  char* progname_;
+  int daemonize_;
+  char* username_;
+  char* groupname_;
+  char* chroot_dir_;
+  char* pid_file_;
+  string_list_t log_targets_;
+  int debug_;
+};
+typedef struct options_struct options_t;
+
+int options_parse_hex_string(const char* hex, buffer_t* buffer);
+
+int options_parse(options_t* opt, int argc, char* argv[]);
+void options_parse_post(options_t* opt);
+void options_default(options_t* opt);
+void options_clear(options_t* opt);
+void options_print_usage();
+void options_print_version();
+void options_print(options_t* opt);
+
+#endif
diff --git a/src/sig_handler.c b/src/sig_handler.c
new file mode 100644
index 0000000..6e6a04a
--- /dev/null
+++ b/src/sig_handler.c
@@ -0,0 +1,152 @@
+/*
+ *  tcpproxy
+ *
+ *  tcpproxy is a simple tcp connection proxy which combines the 
+ *  features of rinetd and 6tunnel. tcpproxy supports IPv4 and 
+ *  IPv6 and also supports connections from IPv6 to IPv4 
+ *  endpoints and vice versa.
+ *  
+ *
+ *  Copyright (C) 2010-2011 Christian Pointner <equinox@spreadspace.org>
+ *                         
+ *  This file is part of tcpproxy.
+ *
+ *  tcpproxy is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  any later version.
+ *
+ *  tcpproxy 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 tcpproxy. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "datatypes.h"
+
+#include "log.h"
+
+#include "sig_handler.h"
+#include <errno.h>
+
+#include <signal.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+static int sig_pipe_fds[2];
+
+static void sig_handler(int sig)
+{
+  sigset_t set;
+  int ret = read(sig_pipe_fds[0], &set, sizeof(sigset_t));
+  if(ret != sizeof(sigset_t))
+    sigemptyset(&set);
+
+  sigaddset(&set, sig);
+  ret = write(sig_pipe_fds[1], &set, sizeof(sigset_t));
+}
+
+
+int signal_init()
+{
+  if(pipe(sig_pipe_fds)) {
+    log_printf(ERROR, "signal handling init failed (pipe error: %s)", strerror(errno));
+    return -1;
+  }
+
+  int i;
+  for(i=0; i<2; ++i) {
+    int fd_flags = fcntl(sig_pipe_fds[i], F_GETFL);
+    if(fd_flags == -1) {
+      log_printf(ERROR, "signal handling init failed (pipe fd[%d] read flags error: %s)", i, strerror(errno));
+      return -1;
+    }
+    if(fcntl(sig_pipe_fds[i], F_SETFL, fd_flags | O_NONBLOCK) == -1){
+      log_printf(ERROR, "signal handling init failed (pipe fd[%d] write flags error: %s)", i, strerror(errno));
+      return -1;
+    }
+  }
+
+  struct sigaction act, act_ign;
+  act.sa_handler = sig_handler;
+  sigfillset(&act.sa_mask);
+  act.sa_flags = 0;
+  act_ign.sa_handler = SIG_IGN;
+  sigfillset(&act_ign.sa_mask);
+  act_ign.sa_flags = 0;
+
+  if((sigaction(SIGINT, &act, NULL) < 0) ||
+     (sigaction(SIGQUIT, &act, NULL) < 0) ||
+     (sigaction(SIGTERM, &act, NULL) < 0) ||
+     (sigaction(SIGHUP, &act, NULL) < 0) ||
+     (sigaction(SIGUSR1, &act, NULL) < 0) ||
+     (sigaction(SIGUSR2, &act, NULL) < 0) ||
+     (sigaction(SIGPIPE, &act_ign, NULL) < 0)) {
+
+    log_printf(ERROR, "signal handling init failed (sigaction error: %s)", strerror(errno));
+    close(sig_pipe_fds[0]);
+    close(sig_pipe_fds[1]);
+  }
+
+  return sig_pipe_fds[0];
+}
+
+int signal_handle()
+{
+  sigset_t set, oldset, tmpset;
+
+  sigemptyset(&tmpset);
+  sigaddset(&tmpset, SIGINT);
+  sigaddset(&tmpset, SIGQUIT);
+  sigaddset(&tmpset, SIGTERM);
+  sigaddset(&tmpset, SIGHUP);
+  sigaddset(&tmpset, SIGUSR1);
+  sigaddset(&tmpset, SIGUSR2);
+  sigprocmask(SIG_BLOCK, &tmpset, &oldset);
+
+  int ret = read(sig_pipe_fds[0], &set, sizeof(sigset_t));
+  if(ret != sizeof(sigset_t))
+    sigemptyset(&set);
+
+  int return_value = 0;
+  int sig;
+  for(sig=1; sig < NSIG; ++sig) {
+    if(sigismember(&set, sig)) {
+      switch(sig) {
+      case SIGINT: log_printf(NOTICE, "SIG-Int caught, exitting"); return_value = 1; break;
+      case SIGQUIT: log_printf(NOTICE, "SIG-Quit caught, exitting"); return_value = 1; break;
+      case SIGTERM: log_printf(NOTICE, "SIG-Term caught, exitting"); return_value = 1; break;
+      case SIGHUP: log_printf(NOTICE, "SIG-Hup caught"); break;
+      case SIGUSR1: log_printf(NOTICE, "SIG-Usr1 caught"); break;
+      case SIGUSR2: log_printf(NOTICE, "SIG-Usr2 caught"); break;
+      default: log_printf(WARNING, "unknown signal %d caught, ignoring", sig); break;
+      }
+      sigdelset(&set, sig);
+    }
+  }
+
+  sigprocmask(SIG_SETMASK, &oldset, NULL);
+  return return_value;
+}
+
+void signal_stop()
+{
+  struct sigaction act;
+  act.sa_handler = SIG_DFL;
+  sigemptyset(&act.sa_mask);
+  act.sa_flags = 0;
+
+  sigaction(SIGINT, &act, NULL);
+  sigaction(SIGQUIT, &act, NULL);
+  sigaction(SIGTERM, &act, NULL);
+  sigaction(SIGHUP, &act, NULL);
+  sigaction(SIGUSR1, &act, NULL);
+  sigaction(SIGUSR2, &act, NULL);
+  sigaction(SIGPIPE, &act, NULL);
+
+  close(sig_pipe_fds[0]);
+  close(sig_pipe_fds[1]);
+}
diff --git a/src/sig_handler.h b/src/sig_handler.h
new file mode 100644
index 0000000..eb19abf
--- /dev/null
+++ b/src/sig_handler.h
@@ -0,0 +1,35 @@
+/*
+ *  tcpproxy
+ *
+ *  tcpproxy is a simple tcp connection proxy which combines the 
+ *  features of rinetd and 6tunnel. tcpproxy supports IPv4 and 
+ *  IPv6 and also supports connections from IPv6 to IPv4 
+ *  endpoints and vice versa.
+ *  
+ *
+ *  Copyright (C) 2010-2011 Christian Pointner <equinox@spreadspace.org>
+ *                         
+ *  This file is part of tcpproxy.
+ *
+ *  tcpproxy is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  any later version.
+ *
+ *  tcpproxy 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 tcpproxy. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef TCPPROXY_sig_handler_h_INCLUDED
+#define TCPPROXY_sig_handler_h_INCLUDED
+
+int signal_init();
+int signal_handle();
+void signal_stop();
+
+#endif
diff --git a/src/string_list.c b/src/string_list.c
new file mode 100644
index 0000000..3c7316d
--- /dev/null
+++ b/src/string_list.c
@@ -0,0 +1,105 @@
+/*
+ *  tcpproxy
+ *
+ *  tcpproxy is a simple tcp connection proxy which combines the 
+ *  features of rinetd and 6tunnel. tcpproxy supports IPv4 and 
+ *  IPv6 and also supports connections from IPv6 to IPv4 
+ *  endpoints and vice versa.
+ *  
+ *
+ *  Copyright (C) 2010-2011 Christian Pointner <equinox@spreadspace.org>
+ *                         
+ *  This file is part of tcpproxy.
+ *
+ *  tcpproxy is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  any later version.
+ *
+ *  tcpproxy 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 tcpproxy. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+#include "string_list.h"
+
+void string_list_init(string_list_t* list)
+{
+  if(!list)
+    return;
+  
+  list->first_ = NULL;
+}
+
+void string_list_clear(string_list_t* list)
+{
+  if(!list)
+    return;
+
+  while(list->first_) {
+    string_list_element_t* tmp;
+    tmp = list->first_;
+    list->first_ = tmp->next_;
+    if(tmp->string_)
+      free(tmp->string_);
+    free(tmp);
+  }
+}
+
+int string_list_add(string_list_t* list, const char* string)
+{
+  if(!list)
+    return -1;
+
+  if(!list->first_) {
+    list->first_ = malloc(sizeof(string_list_element_t));
+    if(!list->first_)
+      return -2;
+
+    list->first_->next_ = 0;
+    list->first_->string_ = strdup(string);
+    if(!list->first_->string_) {
+      free(list->first_);
+      list->first_ = NULL;
+      return -2;
+    }
+  }
+  else {
+    string_list_element_t* tmp = list->first_;
+    while(tmp->next_)
+      tmp = tmp->next_;
+
+    tmp->next_  = malloc(sizeof(string_list_element_t));
+    if(!tmp->next_)
+      return -2;
+
+    tmp->next_->next_ = 0;
+    tmp->next_->string_ = strdup(string);
+    if(!tmp->next_->string_) {
+      free(tmp->next_);
+      tmp->next_ = NULL;
+      return -2;
+    }
+  }
+  return 0;
+}
+
+void string_list_print(string_list_t* list, const char* head, const char* tail)
+{
+  if(!list)
+    return;
+  
+  string_list_element_t* tmp = list->first_;
+  while(tmp) {
+    printf("%s%s%s", head, tmp->string_, tail);
+    tmp = tmp->next_;
+  }
+}
diff --git a/src/string_list.h b/src/string_list.h
new file mode 100644
index 0000000..a9095db
--- /dev/null
+++ b/src/string_list.h
@@ -0,0 +1,48 @@
+/*
+ *  tcpproxy
+ *
+ *  tcpproxy is a simple tcp connection proxy which combines the 
+ *  features of rinetd and 6tunnel. tcpproxy supports IPv4 and 
+ *  IPv6 and also supports connections from IPv6 to IPv4 
+ *  endpoints and vice versa.
+ *  
+ *
+ *  Copyright (C) 2010-2011 Christian Pointner <equinox@spreadspace.org>
+ *                         
+ *  This file is part of tcpproxy.
+ *
+ *  tcpproxy is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  any later version.
+ *
+ *  tcpproxy 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 tcpproxy. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef TCPPROXY_string_list_h_INCLUDED
+#define TCPPROXY_string_list_h_INCLUDED
+
+struct string_list_element_struct {
+  char* string_;
+  struct string_list_element_struct* next_;
+};
+typedef struct string_list_element_struct string_list_element_t;
+
+struct string_list_struct {
+  string_list_element_t* first_;
+};
+typedef struct string_list_struct string_list_t;
+
+void string_list_init(string_list_t* list);
+void string_list_clear(string_list_t* list);
+int string_list_add(string_list_t* list, const char* string);
+
+void string_list_print(string_list_t* list, const char* head, const char* tail);
+
+#endif
diff --git a/src/tcpproxy.c b/src/tcpproxy.c
new file mode 100644
index 0000000..68add0f
--- /dev/null
+++ b/src/tcpproxy.c
@@ -0,0 +1,179 @@
+/*
+ *  tcpproxy
+ *
+ *  tcpproxy is a simple tcp connection proxy which combines the 
+ *  features of rinetd and 6tunnel. tcpproxy supports IPv4 and 
+ *  IPv6 and also supports connections from IPv6 to IPv4 
+ *  endpoints and vice versa.
+ *  
+ *
+ *  Copyright (C) 2010-2011 Christian Pointner <equinox@spreadspace.org>
+ *                         
+ *  This file is part of tcpproxy.
+ *
+ *  tcpproxy is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  any later version.
+ *
+ *  tcpproxy 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 tcpproxy. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+
+#include "datatypes.h"
+#include "options.h"
+#include "string_list.h"
+#include "log.h"
+#include "daemon.h"
+
+int main_loop(options_t* opt)
+{
+  log_printf(INFO, "entering main loop");
+
+  int return_value = 0;
+  int sig_fd = signal_init();
+  if(sig_fd < 0)
+    return_value -1;
+
+  fd_set readfds, readyfds;
+  FD_ZERO(&readfds);
+  FD_SET(sig_fd, &readfds);
+  int nfds = (nfds < sig_fd) ? sig_fd : nfds;
+
+  while(!return_value) {
+    memcpy(&readyfds, &readfds, sizeof(readyfds));
+    int ret = select(nfds + 1, &readyfds, NULL, NULL, NULL);
+    if(ret == -1 && errno != EINTR) {
+      log_printf(ERROR, "select returned with error: %s", strerror(errno));
+      return_value = -1;
+      break;
+    }
+    if(!ret || ret == -1)
+      continue;
+
+    if(FD_ISSET(sig_fd, &readyfds)) {
+      if(signal_handle()) {
+        return_value = 1;
+        break;
+      }
+    }
+  }
+
+  signal_stop();
+  return return_value;
+}
+
+int main(int argc, char* argv[])
+{
+  log_init();
+
+  options_t opt;
+  int ret = options_parse(&opt, argc, argv);
+  if(ret) {
+    if(ret > 0) {
+      fprintf(stderr, "syntax error near: %s\n\n", argv[ret]);
+    }
+    if(ret == -2) {
+      fprintf(stderr, "memory error on options_parse, exitting\n");
+    }
+    if(ret == -3) {
+      options_print_version();
+    }
+
+    if(ret != -2 && ret != -3) 
+      options_print_usage();
+
+    if(ret == -1 || ret == -3)
+      ret = 0;
+
+    options_clear(&opt);
+    log_close();
+    exit(ret);
+  }
+  string_list_element_t* tmp = opt.log_targets_.first_;
+  while(tmp) {
+    ret = log_add_target(tmp->string_);
+    if(ret) {
+      switch(ret) {
+      case -2: fprintf(stderr, "memory error on log_add_target, exitting\n"); break;
+      case -3: fprintf(stderr, "unknown log target: '%s', exitting\n", tmp->string_); break;
+      case -4: fprintf(stderr, "this log target is only allowed once: '%s', exitting\n", tmp->string_); break;
+      default: fprintf(stderr, "syntax error near: '%s', exitting\n", tmp->string_); break;
+      }
+      
+      options_clear(&opt);
+      log_close();
+      exit(ret);
+    }
+    tmp = tmp->next_;
+  }
+
+  log_printf(NOTICE, "just started...");
+  options_parse_post(&opt);
+
+  priv_info_t priv;
+  if(opt.username_)
+    if(priv_init(&priv, opt.username_, opt.groupname_)) {
+      options_clear(&opt);
+      log_close();
+      exit(-1);
+    }
+
+  FILE* pid_file = NULL;
+  if(opt.pid_file_) {
+    pid_file = fopen(opt.pid_file_, "w");
+    if(!pid_file) {
+      log_printf(WARNING, "unable to open pid file: %s", strerror(errno));
+    }
+  }
+
+  if(opt.chroot_dir_)
+    if(do_chroot(opt.chroot_dir_)) {
+      options_clear(&opt);
+      log_close();
+      exit(-1);
+    }
+  if(opt.username_)
+    if(priv_drop(&priv)) {
+      options_clear(&opt);
+      log_close();
+      exit(-1);
+    }  
+
+  if(opt.daemonize_) {
+    pid_t oldpid = getpid();
+    daemonize();
+    log_printf(INFO, "running in background now (old pid: %d)", oldpid);
+  }
+
+  if(pid_file) {
+    pid_t pid = getpid();
+    fprintf(pid_file, "%d", pid);
+    fclose(pid_file);
+  }
+
+  ret = main_loop(&opt);
+
+  options_clear(&opt);
+
+  if(!ret)
+    log_printf(NOTICE, "normal shutdown");
+  else if(ret < 0)
+    log_printf(NOTICE, "shutdown after error");
+  else
+    log_printf(NOTICE, "shutdown after signal");
+
+  log_close();
+
+	return ret;
+}