Imported Upstream version 2.3_rc1

1 files changed, 2089 insertions, 0 deletions

diff --git a/src/openvpn/misc.c b/src/openvpn/misc.c
new file mode 100644
index 0000000..fcc8552
--- /dev/null
+++ b/src/openvpn/misc.c
@@ -0,0 +1,2089 @@
+/*
+ *  OpenVPN -- An application to securely tunnel IP networks
+ *             over a single TCP/UDP port, with support for SSL/TLS-based
+ *             session authentication and key exchange,
+ *             packet encryption, packet authentication, and
+ *             packet compression.
+ *
+ *  Copyright (C) 2002-2010 OpenVPN Technologies, Inc. <sales@openvpn.net>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program 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 this program (see the file COPYING included with this
+ *  distribution); if not, write to the Free Software Foundation, Inc.,
+ *  59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#elif defined(_MSC_VER)
+#include "config-msvc.h"
+#endif
+
+#include "syshead.h"
+
+#include "buffer.h"
+#include "misc.h"
+#include "base64.h"
+#include "tun.h"
+#include "error.h"
+#include "otime.h"
+#include "plugin.h"
+#include "options.h"
+#include "manage.h"
+#include "crypto.h"
+#include "route.h"
+#include "console.h"
+#include "win32.h"
+
+#include "memdbg.h"
+
+#ifdef ENABLE_IPROUTE
+const char *iproute_path = IPROUTE_PATH; /* GLOBAL */
+#endif
+
+/* contains an SSEC_x value defined in misc.h */
+int script_security = SSEC_BUILT_IN; /* GLOBAL */
+
+/*
+ * Pass tunnel endpoint and MTU parms to a user-supplied script.
+ * Used to execute the up/down script/plugins.
+ */
+void
+run_up_down (const char *command,
+	     const struct plugin_list *plugins,
+	     int plugin_type,
+	     const char *arg,
+	     const char *dev_type,
+	     int tun_mtu,
+	     int link_mtu,
+	     const char *ifconfig_local,
+	     const char* ifconfig_remote,
+	     const char *context,
+	     const char *signal_text,
+	     const char *script_type,
+	     struct env_set *es)
+{
+  struct gc_arena gc = gc_new ();
+
+  if (signal_text)
+    setenv_str (es, "signal", signal_text);
+  setenv_str (es, "script_context", context);
+  setenv_int (es, "tun_mtu", tun_mtu);
+  setenv_int (es, "link_mtu", link_mtu);
+  setenv_str (es, "dev", arg);
+  if (dev_type)
+    setenv_str (es, "dev_type", dev_type);
+
+  if (!ifconfig_local)
+    ifconfig_local = "";
+  if (!ifconfig_remote)
+    ifconfig_remote = "";
+  if (!context)
+    context = "";
+
+  if (plugin_defined (plugins, plugin_type))
+    {
+      struct argv argv = argv_new ();
+      ASSERT (arg);
+      argv_printf (&argv,
+		   "%s %d %d %s %s %s",
+		   arg,
+		   tun_mtu, link_mtu,
+		   ifconfig_local, ifconfig_remote,
+		   context);
+
+      if (plugin_call (plugins, plugin_type, &argv, NULL, es) != OPENVPN_PLUGIN_FUNC_SUCCESS)
+	msg (M_FATAL, "ERROR: up/down plugin call failed");
+
+      argv_reset (&argv);
+    }
+
+  if (command)
+    {
+      struct argv argv = argv_new ();
+      ASSERT (arg);
+      setenv_str (es, "script_type", script_type);
+      argv_printf (&argv,
+		  "%sc %s %d %d %s %s %s",
+		  command,
+		  arg,
+		  tun_mtu, link_mtu,
+		  ifconfig_local, ifconfig_remote,
+		  context);
+      argv_msg (M_INFO, &argv);
+      openvpn_run_script (&argv, es, S_FATAL, "--up/--down");
+      argv_reset (&argv);
+    }
+
+  gc_free (&gc);
+}
+
+/* Get the file we will later write our process ID to */
+void
+get_pid_file (const char* filename, struct pid_state *state)
+{
+  CLEAR (*state);
+  if (filename)
+    {
+      state->fp = platform_fopen (filename, "w");
+      if (!state->fp)
+	msg (M_ERR, "Open error on pid file %s", filename);
+      state->filename = filename;
+    }
+}
+
+/* Write our PID to a file */
+void
+write_pid (const struct pid_state *state)
+{
+  if (state->filename && state->fp)
+    {
+      unsigned int pid = platform_getpid (); 
+      fprintf(state->fp, "%u\n", pid);
+      if (fclose (state->fp))
+	msg (M_ERR, "Close error on pid file %s", state->filename);
+    }
+}
+
+/*
+ * Set standard file descriptors to /dev/null
+ */
+void
+set_std_files_to_null (bool stdin_only)
+{
+#if defined(HAVE_DUP) && defined(HAVE_DUP2)
+  int fd;
+  if ((fd = open ("/dev/null", O_RDWR, 0)) != -1)
+    {
+      dup2 (fd, 0);
+      if (!stdin_only)
+	{
+	  dup2 (fd, 1);
+	  dup2 (fd, 2);
+	}
+      if (fd > 2)
+	close (fd);
+    }
+#endif
+}
+
+/*
+ *  dup inetd/xinetd socket descriptor and save
+ */
+
+int inetd_socket_descriptor = SOCKET_UNDEFINED; /* GLOBAL */
+
+void
+save_inetd_socket_descriptor (void)
+{
+  inetd_socket_descriptor = INETD_SOCKET_DESCRIPTOR;
+#if defined(HAVE_DUP) && defined(HAVE_DUP2)
+  /* use handle passed by inetd/xinetd */
+  if ((inetd_socket_descriptor = dup (INETD_SOCKET_DESCRIPTOR)) < 0)
+    msg (M_ERR, "INETD_SOCKET_DESCRIPTOR dup(%d) failed", INETD_SOCKET_DESCRIPTOR);
+  set_std_files_to_null (true);
+#endif
+}
+
+/*
+ * Warn if a given file is group/others accessible.
+ */
+void
+warn_if_group_others_accessible (const char* filename)
+{
+#ifndef WIN32
+#ifdef HAVE_STAT
+  if (strcmp (filename, INLINE_FILE_TAG))
+    {
+      struct stat st;
+      if (stat (filename, &st))
+	{
+	  msg (M_WARN | M_ERRNO, "WARNING: cannot stat file '%s'", filename);
+	}
+      else
+	{
+	  if (st.st_mode & (S_IRWXG|S_IRWXO))
+	    msg (M_WARN, "WARNING: file '%s' is group or others accessible", filename);
+	}
+    }
+#endif
+#endif
+}
+
+/*
+ * Print an error message based on the status code returned by system().
+ */
+const char *
+system_error_message (int stat, struct gc_arena *gc)
+{
+  struct buffer out = alloc_buf_gc (256, gc);
+#ifdef WIN32
+  if (stat == -1)
+    buf_printf (&out, "external program did not execute -- ");
+  buf_printf (&out, "returned error code %d", stat);
+#else
+  if (stat == -1)
+    buf_printf (&out, "external program fork failed");
+  else if (!WIFEXITED (stat))
+    buf_printf (&out, "external program did not exit normally");
+  else
+    {
+      const int cmd_ret = WEXITSTATUS (stat);
+      if (!cmd_ret)
+	buf_printf (&out, "external program exited normally");
+      else if (cmd_ret == 127)
+	buf_printf (&out, "could not execute external program");
+      else
+	buf_printf (&out, "external program exited with error status: %d", cmd_ret);
+    }
+#endif
+  return (const char *)out.data;
+}
+
+/*
+ * Wrapper around openvpn_execve
+ */
+bool
+openvpn_execve_check (const struct argv *a, const struct env_set *es, const unsigned int flags, const char *error_message)
+{
+  struct gc_arena gc = gc_new ();
+  const int stat = openvpn_execve (a, es, flags);
+  int ret = false;
+
+  if (platform_system_ok (stat))
+    ret = true;
+  else
+    {
+      if (error_message)
+	msg (((flags & S_FATAL) ? M_FATAL : M_WARN), "%s: %s",
+	     error_message,
+	     system_error_message (stat, &gc));
+    }
+  gc_free (&gc);
+  return ret;
+}
+
+bool
+openvpn_execve_allowed (const unsigned int flags)
+{
+  if (flags & S_SCRIPT)
+    return script_security >= SSEC_SCRIPTS;
+  else
+    return script_security >= SSEC_BUILT_IN;
+}
+
+
+#ifndef WIN32
+/*
+ * Run execve() inside a fork().  Designed to replicate the semantics of system() but
+ * in a safer way that doesn't require the invocation of a shell or the risks
+ * assocated with formatting and parsing a command line.
+ */
+int
+openvpn_execve (const struct argv *a, const struct env_set *es, const unsigned int flags)
+{
+  struct gc_arena gc = gc_new ();
+  int ret = -1;
+  static bool warn_shown = false;
+
+  if (a && a->argv[0])
+    {
+#if defined(ENABLE_FEATURE_EXECVE)
+      if (openvpn_execve_allowed (flags))
+	{
+          const char *cmd = a->argv[0];
+          char *const *argv = a->argv;
+          char *const *envp = (char *const *)make_env_array (es, true, &gc);
+          pid_t pid;
+
+          pid = fork ();
+          if (pid == (pid_t)0) /* child side */
+            {
+              execve (cmd, argv, envp);
+              exit (127);
+            }
+          else if (pid < (pid_t)0) /* fork failed */
+            msg (M_ERR, "openvpn_execve: unable to fork");
+          else /* parent side */
+            {
+              if (waitpid (pid, &ret, 0) != pid)
+                ret = -1;
+            }
+        }
+      else if (!warn_shown && (script_security < SSEC_SCRIPTS))
+	{
+	  msg (M_WARN, SCRIPT_SECURITY_WARNING);
+          warn_shown = true;
+	}
+#else
+      msg (M_WARN, "openvpn_execve: execve function not available");
+#endif
+    }
+  else
+    {
+      msg (M_FATAL, "openvpn_execve: called with empty argv");
+    }
+
+  gc_free (&gc);
+  return ret;
+}
+#endif
+
+/*
+ * Run execve() inside a fork(), duping stdout.  Designed to replicate the semantics of popen() but
+ * in a safer way that doesn't require the invocation of a shell or the risks
+ * assocated with formatting and parsing a command line.
+ */
+int
+openvpn_popen (const struct argv *a,  const struct env_set *es)
+{
+  struct gc_arena gc = gc_new ();
+  int ret = -1;
+  static bool warn_shown = false;
+
+  if (a && a->argv[0])
+    {
+#if defined(ENABLE_FEATURE_EXECVE)
+      if (script_security >= SSEC_BUILT_IN)
+	{
+	      const char *cmd = a->argv[0];
+	      char *const *argv = a->argv;
+	      char *const *envp = (char *const *)make_env_array (es, true, &gc);
+	      pid_t pid;
+	      int pipe_stdout[2];
+
+              if (pipe (pipe_stdout) == 0) {
+		      pid = fork ();
+		      if (pid == (pid_t)0) /* child side */
+			{
+			  close (pipe_stdout[0]);
+			  dup2 (pipe_stdout[1],1);
+			  execve (cmd, argv, envp);
+			  exit (127);
+			}
+		      else if (pid < (pid_t)0) /* fork failed */
+			{
+			  msg (M_ERR, "openvpn_popen: unable to fork");
+			}
+		      else /* parent side */
+			{
+                            ret=pipe_stdout[0];
+			    close (pipe_stdout[1]);
+			}
+	      }
+	      else {
+		      msg (M_WARN, "openvpn_popen: unable to create stdout pipe");
+		      ret = -1;
+	      }
+	}
+      else if (!warn_shown && (script_security < SSEC_SCRIPTS))
+	{
+	  msg (M_WARN, SCRIPT_SECURITY_WARNING);
+          warn_shown = true;
+	}
+#else
+      msg (M_WARN, "openvpn_popen: execve function not available");
+#endif
+    }
+  else
+    {
+      msg (M_FATAL, "openvpn_popen: called with empty argv");
+    }
+
+  gc_free (&gc);
+  return ret;
+}
+
+
+
+/*
+ * Initialize random number seed.  random() is only used
+ * when "weak" random numbers are acceptable.
+ * OpenSSL routines are always used when cryptographically
+ * strong random numbers are required.
+ */
+
+void
+init_random_seed(void)
+{
+  struct timeval tv;
+
+  if (!gettimeofday (&tv, NULL))
+    {
+      const unsigned int seed = (unsigned int) tv.tv_sec ^ tv.tv_usec;
+      srandom (seed);
+    }
+}
+
+/* thread-safe strerror */
+
+const char *
+strerror_ts (int errnum, struct gc_arena *gc)
+{
+#ifdef HAVE_STRERROR
+  struct buffer out = alloc_buf_gc (256, gc);
+
+  buf_printf (&out, "%s", openvpn_strerror (errnum, gc));
+  return BSTR (&out);
+#else
+  return "[error string unavailable]";
+#endif
+}
+
+/*
+ * Set environmental variable (int or string).
+ *
+ * On Posix, we use putenv for portability,
+ * and put up with its painful semantics
+ * that require all the support code below.
+ */
+
+/* General-purpose environmental variable set functions */
+
+static char *
+construct_name_value (const char *name, const char *value, struct gc_arena *gc)
+{
+  struct buffer out;
+
+  ASSERT (name);
+  if (!value)
+    value = "";
+  out = alloc_buf_gc (strlen (name) + strlen (value) + 2, gc);
+  buf_printf (&out, "%s=%s", name, value);
+  return BSTR (&out);
+}
+
+bool
+deconstruct_name_value (const char *str, const char **name, const char **value, struct gc_arena *gc)
+{
+  char *cp;
+
+  ASSERT (str);
+  ASSERT (name && value);
+
+  *name = cp = string_alloc (str, gc);
+  *value = NULL;
+
+  while ((*cp))
+    {
+      if (*cp == '=' && !*value)
+	{
+	  *cp = 0;
+	  *value = cp + 1;
+	}
+      ++cp;
+    }
+  return *name && *value;
+}
+
+static bool
+env_string_equal (const char *s1, const char *s2)
+{
+  int c1, c2;
+  ASSERT (s1);
+  ASSERT (s2);
+
+  while (true)
+    {
+      c1 = *s1++;
+      c2 = *s2++;
+      if (c1 == '=')
+	c1 = 0;
+      if (c2 == '=')
+	c2 = 0;
+      if (!c1 && !c2)
+	return true;
+      if (c1 != c2)
+	break;
+    }
+  return false;
+}
+
+static bool
+remove_env_item (const char *str, const bool do_free, struct env_item **list)
+{
+  struct env_item *current, *prev;
+
+  ASSERT (str);
+  ASSERT (list);
+
+  for (current = *list, prev = NULL; current != NULL; current = current->next)
+    {
+      if (env_string_equal (current->string, str))
+	{
+	  if (prev)
+	    prev->next = current->next;
+	  else
+	    *list = current->next;
+	  if (do_free)
+	    {
+	      memset (current->string, 0, strlen (current->string));
+	      free (current->string);
+	      free (current);
+	    }
+	  return true;
+	}
+      prev = current;
+    }
+  return false;
+}
+
+static void
+add_env_item (char *str, const bool do_alloc, struct env_item **list, struct gc_arena *gc)
+{
+  struct env_item *item;
+
+  ASSERT (str);
+  ASSERT (list);
+
+  ALLOC_OBJ_GC (item, struct env_item, gc);
+  item->string = do_alloc ? string_alloc (str, gc): str;
+  item->next = *list;
+  *list = item;
+}
+
+/* struct env_set functions */
+
+static bool
+env_set_del_nolock (struct env_set *es, const char *str)
+{
+  return remove_env_item (str, es->gc == NULL, &es->list);
+}
+
+static void
+env_set_add_nolock (struct env_set *es, const char *str)
+{
+  remove_env_item (str, es->gc == NULL, &es->list);  
+  add_env_item ((char *)str, true, &es->list, es->gc);
+}
+
+struct env_set *
+env_set_create (struct gc_arena *gc)
+{
+  struct env_set *es;
+  ALLOC_OBJ_CLEAR_GC (es, struct env_set, gc);
+  es->list = NULL;
+  es->gc = gc;
+  return es;
+}
+
+void
+env_set_destroy (struct env_set *es)
+{
+  if (es && es->gc == NULL)
+    {
+      struct env_item *e = es->list;
+      while (e)
+	{
+	  struct env_item *next = e->next;
+	  free (e->string);
+	  free (e);
+	  e = next;
+	}
+      free (es);
+    }
+}
+
+bool
+env_set_del (struct env_set *es, const char *str)
+{
+  bool ret;
+  ASSERT (es);
+  ASSERT (str);
+  ret = env_set_del_nolock (es, str);
+  return ret;
+}
+
+void
+env_set_add (struct env_set *es, const char *str)
+{
+  ASSERT (es);
+  ASSERT (str);
+  env_set_add_nolock (es, str);
+}
+
+void
+env_set_print (int msglevel, const struct env_set *es)
+{
+  if (check_debug_level (msglevel))
+    {
+      const struct env_item *e;
+      int i;
+
+      if (es)
+	{
+	  e = es->list;
+	  i = 0;
+
+	  while (e)
+	    {
+	      if (env_safe_to_print (e->string))
+		msg (msglevel, "ENV [%d] '%s'", i, e->string);
+	      ++i;
+	      e = e->next;
+	    }
+	}
+    }
+}
+
+void
+env_set_inherit (struct env_set *es, const struct env_set *src)
+{
+  const struct env_item *e;
+
+  ASSERT (es);
+
+  if (src)
+    {
+      e = src->list;
+      while (e)
+	{
+	  env_set_add_nolock (es, e->string);
+	  e = e->next;
+	}
+    }
+}
+
+void
+env_set_add_to_environment (const struct env_set *es)
+{
+  if (es)
+    {
+      struct gc_arena gc = gc_new ();
+      const struct env_item *e;
+
+      e = es->list;
+
+      while (e)
+	{
+	  const char *name;
+	  const char *value;
+
+	  if (deconstruct_name_value (e->string, &name, &value, &gc))
+	    setenv_str (NULL, name, value);
+
+	  e = e->next;
+	}
+      gc_free (&gc);
+    }
+}
+
+void
+env_set_remove_from_environment (const struct env_set *es)
+{
+  if (es)
+    {
+      struct gc_arena gc = gc_new ();
+      const struct env_item *e;
+
+      e = es->list;
+
+      while (e)
+	{
+	  const char *name;
+	  const char *value;
+
+	  if (deconstruct_name_value (e->string, &name, &value, &gc))
+	    setenv_del (NULL, name);
+
+	  e = e->next;
+	}
+      gc_free (&gc);
+    }
+}
+
+#ifdef HAVE_PUTENV
+
+/* companion functions to putenv */
+
+static struct env_item *global_env = NULL; /* GLOBAL */
+
+void
+manage_env (char *str)
+{
+  remove_env_item (str, true, &global_env);
+  add_env_item (str, false, &global_env, NULL);
+}
+
+#endif
+
+/* add/modify/delete environmental strings */
+
+void
+setenv_counter (struct env_set *es, const char *name, counter_type value)
+{
+  char buf[64];
+  openvpn_snprintf (buf, sizeof(buf), counter_format, value);
+  setenv_str (es, name, buf);
+}
+
+void
+setenv_int (struct env_set *es, const char *name, int value)
+{
+  char buf[64];
+  openvpn_snprintf (buf, sizeof(buf), "%d", value);
+  setenv_str (es, name, buf);
+}
+
+void
+setenv_unsigned (struct env_set *es, const char *name, unsigned int value)
+{
+  char buf[64];
+  openvpn_snprintf (buf, sizeof(buf), "%u", value);
+  setenv_str (es, name, buf);
+}
+
+void
+setenv_str (struct env_set *es, const char *name, const char *value)
+{
+  setenv_str_ex (es, name, value, CC_NAME, 0, 0, CC_PRINT, 0, 0);
+}
+
+void
+setenv_str_safe (struct env_set *es, const char *name, const char *value)
+{
+  uint8_t b[64];
+  struct buffer buf;
+  buf_set_write (&buf, b, sizeof (b));
+  if (buf_printf (&buf, "OPENVPN_%s", name))
+    setenv_str (es, BSTR(&buf), value);
+  else
+    msg (M_WARN, "setenv_str_safe: name overflow");
+}
+
+void
+setenv_del (struct env_set *es, const char *name)
+{
+  ASSERT (name);
+  setenv_str (es, name, NULL);
+}
+
+void
+setenv_str_ex (struct env_set *es,
+	       const char *name,
+	       const char *value,
+	       const unsigned int name_include,
+	       const unsigned int name_exclude,
+	       const char name_replace,
+	       const unsigned int value_include,
+	       const unsigned int value_exclude,
+	       const char value_replace)
+{
+  struct gc_arena gc = gc_new ();
+  const char *name_tmp;
+  const char *val_tmp = NULL;
+
+  ASSERT (name && strlen (name) > 1);
+
+  name_tmp = string_mod_const (name, name_include, name_exclude, name_replace, &gc);
+
+  if (value)
+    val_tmp = string_mod_const (value, value_include, value_exclude, value_replace, &gc);
+
+  if (es)
+    {
+      if (val_tmp)
+	{
+	  const char *str = construct_name_value (name_tmp, val_tmp, &gc);
+	  env_set_add (es, str);
+#if DEBUG_VERBOSE_SETENV
+	  msg (M_INFO, "SETENV_ES '%s'", str);
+#endif
+	}
+      else
+	env_set_del (es, name_tmp);
+    }
+  else
+    {
+      char *str = construct_name_value (name_tmp, val_tmp, NULL);
+      if (platform_putenv(str))
+      {
+        msg (M_WARN | M_ERRNO, "putenv('%s') failed", str);
+      }
+    }
+
+  gc_free (&gc);
+}
+
+/*
+ * Setenv functions that append an integer index to the name
+ */
+static const char *
+setenv_format_indexed_name (const char *name, const int i, struct gc_arena *gc)
+{
+  struct buffer out = alloc_buf_gc (strlen (name) + 16, gc);
+  if (i >= 0)
+    buf_printf (&out, "%s_%d", name, i);
+  else
+    buf_printf (&out, "%s", name);
+  return BSTR (&out);
+}
+
+void
+setenv_int_i (struct env_set *es, const char *name, const int value, const int i)
+{
+  struct gc_arena gc = gc_new ();
+  const char *name_str = setenv_format_indexed_name (name, i, &gc);
+  setenv_int (es, name_str, value);
+  gc_free (&gc);
+}
+
+void
+setenv_str_i (struct env_set *es, const char *name, const char *value, const int i)
+{
+  struct gc_arena gc = gc_new ();
+  const char *name_str = setenv_format_indexed_name (name, i, &gc);
+  setenv_str (es, name_str, value);
+  gc_free (&gc);
+}
+
+/*
+ * taken from busybox networking/ifupdown.c
+ */
+unsigned int
+count_bits(unsigned int a)
+{
+  unsigned int result;
+  result = (a & 0x55) + ((a >> 1) & 0x55);
+  result = (result & 0x33) + ((result >> 2) & 0x33);
+  return((result & 0x0F) + ((result >> 4) & 0x0F));
+}
+
+int
+count_netmask_bits(const char *dotted_quad)
+{
+  unsigned int result, a, b, c, d;
+  /* Found a netmask...  Check if it is dotted quad */
+  if (sscanf(dotted_quad, "%u.%u.%u.%u", &a, &b, &c, &d) != 4)
+    return -1;
+  result = count_bits(a);
+  result += count_bits(b);
+  result += count_bits(c);
+  result += count_bits(d);
+  return ((int)result);
+}
+
+/* return true if filename can be opened for read */
+bool
+test_file (const char *filename)
+{
+  bool ret = false;
+  if (filename)
+    {
+      FILE *fp = platform_fopen (filename, "r");
+      if (fp)
+	{
+	  fclose (fp);
+	  ret = true;
+	}
+    }
+
+  dmsg (D_TEST_FILE, "TEST FILE '%s' [%d]",
+       filename ? filename : "UNDEF",
+       ret);
+
+  return ret;
+}
+
+#ifdef ENABLE_CRYPTO
+
+/* create a temporary filename in directory */
+const char *
+create_temp_file (const char *directory, const char *prefix, struct gc_arena *gc)
+{
+  static unsigned int counter;
+  struct buffer fname = alloc_buf_gc (256, gc);
+  int fd;
+  const char *retfname = NULL;
+  unsigned int attempts = 0;
+
+  do
+    {
+      uint8_t rndbytes[16];
+      const char *rndstr;
+
+      ++attempts;
+      ++counter;
+
+      prng_bytes (rndbytes, sizeof rndbytes);
+      rndstr = format_hex_ex (rndbytes, sizeof rndbytes, 40, 0, NULL, gc);
+      buf_printf (&fname, PACKAGE "_%s_%s.tmp", prefix, rndstr);
+
+      retfname = gen_path (directory, BSTR (&fname), gc);
+      if (!retfname)
+        {
+          msg (M_FATAL, "Failed to create temporary filename and path");
+          return NULL;
+        }
+
+      /* Atomically create the file.  Errors out if the file already
+         exists.  */
+      fd = platform_open (retfname, O_CREAT | O_EXCL | O_WRONLY, S_IRUSR | S_IWUSR);
+      if (fd != -1)
+        {
+          close (fd);
+          return retfname;
+        }
+      else if (fd == -1 && errno != EEXIST)
+        {
+          /* Something else went wrong, no need to retry.  */
+          struct gc_arena gcerr = gc_new ();
+          msg (M_FATAL, "Could not create temporary file '%s': %s",
+               retfname, strerror_ts (errno, &gcerr));
+          gc_free (&gcerr);
+          return NULL;
+        }
+    }
+  while (attempts < 6);
+
+  msg (M_FATAL, "Failed to create temporary file after %i attempts", attempts);
+  return NULL;
+}
+
+/*
+ * Add a random string to first DNS label of hostname to prevent DNS caching.
+ * For example, foo.bar.gov would be modified to <random-chars>.foo.bar.gov.
+ * Of course, this requires explicit support in the DNS server.
+ */
+const char *
+hostname_randomize(const char *hostname, struct gc_arena *gc)
+{
+# define n_rnd_bytes 6
+
+  char *hst = string_alloc(hostname, gc);
+  char *dot = strchr(hst, '.');
+
+  if (dot)
+    {
+      uint8_t rnd_bytes[n_rnd_bytes];
+      const char *rnd_str;
+      struct buffer hname = alloc_buf_gc (strlen(hostname)+sizeof(rnd_bytes)*2+4, gc);
+
+      *dot++ = '\0';
+      prng_bytes (rnd_bytes, sizeof (rnd_bytes));
+      rnd_str = format_hex_ex (rnd_bytes, sizeof (rnd_bytes), 40, 0, NULL, gc);
+      buf_printf(&hname, "%s-0x%s.%s", hst, rnd_str, dot);
+      return BSTR(&hname);
+    }
+  else
+    return hostname;
+# undef n_rnd_bytes
+}
+
+#else
+
+const char *
+hostname_randomize(const char *hostname, struct gc_arena *gc)
+{
+  msg (M_WARN, "WARNING: hostname randomization disabled when crypto support is not compiled");
+  return hostname;
+}
+
+#endif
+
+/*
+ * Put a directory and filename together.
+ */
+const char *
+gen_path (const char *directory, const char *filename, struct gc_arena *gc)
+{
+#if WIN32
+  const int CC_PATH_RESERVED = CC_LESS_THAN|CC_GREATER_THAN|CC_COLON|
+    CC_DOUBLE_QUOTE|CC_SLASH|CC_BACKSLASH|CC_PIPE|CC_QUESTION_MARK|CC_ASTERISK;
+#else
+  const int CC_PATH_RESERVED = CC_SLASH;
+#endif
+  const char *safe_filename = string_mod_const (filename, CC_PRINT, CC_PATH_RESERVED, '_', gc);
+
+  if (safe_filename
+      && strcmp (safe_filename, ".")
+      && strcmp (safe_filename, "..")
+#ifdef WIN32
+      && win_safe_filename (safe_filename)
+#endif
+      )
+    {
+      const size_t outsize = strlen(safe_filename) + (directory ? strlen (directory) : 0) + 16;
+      struct buffer out = alloc_buf_gc (outsize, gc);
+      char dirsep[2];
+
+      dirsep[0] = OS_SPECIFIC_DIRSEP;
+      dirsep[1] = '\0';
+
+      if (directory)
+	buf_printf (&out, "%s%s", directory, dirsep);
+      buf_printf (&out, "%s", safe_filename);
+
+      return BSTR (&out);
+    }
+  else
+    return NULL;
+}
+
+bool
+absolute_pathname (const char *pathname)
+{
+  if (pathname)
+    {
+      const int c = pathname[0];
+#ifdef WIN32
+      return c == '\\' || (isalpha(c) && pathname[1] == ':' && pathname[2] == '\\');
+#else
+      return c == '/';
+#endif
+    }
+  else
+    return false;
+}
+
+/*
+ * Get and store a username/password
+ */
+
+bool
+get_user_pass_cr (struct user_pass *up,
+		  const char *auth_file,
+		  const char *prefix,
+		  const unsigned int flags,
+		  const char *auth_challenge)
+{
+  struct gc_arena gc = gc_new ();
+
+  if (!up->defined)
+    {
+      const bool from_stdin = (!auth_file || !strcmp (auth_file, "stdin"));
+
+      if (flags & GET_USER_PASS_PREVIOUS_CREDS_FAILED)
+	msg (M_WARN, "Note: previous '%s' credentials failed", prefix);
+
+#ifdef ENABLE_MANAGEMENT
+      /*
+       * Get username/password from management interface?
+       */
+      if (management
+	  && ((auth_file && streq (auth_file, "management")) || (from_stdin && (flags & GET_USER_PASS_MANAGEMENT)))
+	  && management_query_user_pass_enabled (management))
+	{
+	  const char *sc = NULL;
+
+	  if (flags & GET_USER_PASS_PREVIOUS_CREDS_FAILED)
+	    management_auth_failure (management, prefix, "previous auth credentials failed");
+
+#ifdef ENABLE_CLIENT_CR
+	  if (auth_challenge && (flags & GET_USER_PASS_STATIC_CHALLENGE))
+	    sc = auth_challenge;
+#endif
+	  if (!management_query_user_pass (management, up, prefix, flags, sc))
+	    {
+	      if ((flags & GET_USER_PASS_NOFATAL) != 0)
+		return false;
+	      else
+		msg (M_FATAL, "ERROR: could not read %s username/password/ok/string from management interface", prefix);
+	    }
+	}
+      else
+#endif
+      /*
+       * Get NEED_OK confirmation from the console
+       */
+      if (flags & GET_USER_PASS_NEED_OK)
+	{
+	  struct buffer user_prompt = alloc_buf_gc (128, &gc);
+
+	  buf_printf (&user_prompt, "NEED-OK|%s|%s:", prefix, up->username);
+	  
+	  if (!get_console_input (BSTR (&user_prompt), true, up->password, USER_PASS_LEN))
+	    msg (M_FATAL, "ERROR: could not read %s ok-confirmation from stdin", prefix);
+	  
+	  if (!strlen (up->password))
+	    strcpy (up->password, "ok");
+	}
+	  
+      /*
+       * Get username/password from standard input?
+       */
+      else if (from_stdin)
+	{
+#ifdef ENABLE_CLIENT_CR
+	  if (auth_challenge && (flags & GET_USER_PASS_DYNAMIC_CHALLENGE))
+	    {
+	      struct auth_challenge_info *ac = get_auth_challenge (auth_challenge, &gc);
+	      if (ac)
+		{
+		  char *response = (char *) gc_malloc (USER_PASS_LEN, false, &gc);
+		  struct buffer packed_resp;
+
+		  buf_set_write (&packed_resp, (uint8_t*)up->password, USER_PASS_LEN);
+		  msg (M_INFO|M_NOPREFIX, "CHALLENGE: %s", ac->challenge_text);
+		  if (!get_console_input ("Response:", BOOL_CAST(ac->flags&CR_ECHO), response, USER_PASS_LEN))
+		    msg (M_FATAL, "ERROR: could not read challenge response from stdin");
+		  strncpynt (up->username, ac->user, USER_PASS_LEN);
+		  buf_printf (&packed_resp, "CRV1::%s::%s", ac->state_id, response);
+		}
+	      else
+		{
+		  msg (M_FATAL, "ERROR: received malformed challenge request from server");
+		}
+	    }
+	  else
+#endif
+	    {
+	      struct buffer user_prompt = alloc_buf_gc (128, &gc);
+	      struct buffer pass_prompt = alloc_buf_gc (128, &gc);
+
+	      buf_printf (&user_prompt, "Enter %s Username:", prefix);
+	      buf_printf (&pass_prompt, "Enter %s Password:", prefix);
+
+	      if (!(flags & GET_USER_PASS_PASSWORD_ONLY))
+		{
+		  if (!get_console_input (BSTR (&user_prompt), true, up->username, USER_PASS_LEN))
+		    msg (M_FATAL, "ERROR: could not read %s username from stdin", prefix);
+		  if (strlen (up->username) == 0)
+		    msg (M_FATAL, "ERROR: %s username is empty", prefix);
+		}
+
+	      if (!get_console_input (BSTR (&pass_prompt), false, up->password, USER_PASS_LEN))
+		msg (M_FATAL, "ERROR: could not not read %s password from stdin", prefix);
+
+#ifdef ENABLE_CLIENT_CR
+	      if (auth_challenge && (flags & GET_USER_PASS_STATIC_CHALLENGE))
+		{
+		  char *response = (char *) gc_malloc (USER_PASS_LEN, false, &gc);
+		  struct buffer packed_resp;
+		  char *pw64=NULL, *resp64=NULL;
+
+		  msg (M_INFO|M_NOPREFIX, "CHALLENGE: %s", auth_challenge);
+		  if (!get_console_input ("Response:", BOOL_CAST(flags & GET_USER_PASS_STATIC_CHALLENGE_ECHO), response, USER_PASS_LEN))
+		    msg (M_FATAL, "ERROR: could not read static challenge response from stdin");
+		  if (openvpn_base64_encode(up->password, strlen(up->password), &pw64) == -1
+		      || openvpn_base64_encode(response, strlen(response), &resp64) == -1)
+		    msg (M_FATAL, "ERROR: could not base64-encode password/static_response");
+		  buf_set_write (&packed_resp, (uint8_t*)up->password, USER_PASS_LEN);
+		  buf_printf (&packed_resp, "SCRV1:%s:%s", pw64, resp64);
+		  string_clear(pw64);
+		  free(pw64);
+		  string_clear(resp64);
+		  free(resp64);
+		}
+#endif
+	    }
+	}
+      else
+	{
+	  /*
+	   * Get username/password from a file.
+	   */
+	  FILE *fp;
+      
+#ifndef ENABLE_PASSWORD_SAVE
+	  /*
+	   * Unless ENABLE_PASSWORD_SAVE is defined, don't allow sensitive passwords
+	   * to be read from a file.
+	   */
+	  if (flags & GET_USER_PASS_SENSITIVE)
+	    msg (M_FATAL, "Sorry, '%s' password cannot be read from a file", prefix);
+#endif
+
+	  warn_if_group_others_accessible (auth_file);
+
+	  fp = platform_fopen (auth_file, "r");
+	  if (!fp)
+	    msg (M_ERR, "Error opening '%s' auth file: %s", prefix, auth_file);
+
+	  if (flags & GET_USER_PASS_PASSWORD_ONLY)
+	    {
+	      if (fgets (up->password, USER_PASS_LEN, fp) == NULL)
+		msg (M_FATAL, "Error reading password from %s authfile: %s",
+		     prefix,
+		     auth_file);
+	    }
+	  else
+	    {
+	      if (fgets (up->username, USER_PASS_LEN, fp) == NULL
+		  || fgets (up->password, USER_PASS_LEN, fp) == NULL)
+		msg (M_FATAL, "Error reading username and password (must be on two consecutive lines) from %s authfile: %s",
+		     prefix,
+		     auth_file);
+	    }
+      
+	  fclose (fp);
+      
+	  chomp (up->username);
+	  chomp (up->password);
+      
+	  if (!(flags & GET_USER_PASS_PASSWORD_ONLY) && strlen (up->username) == 0)
+	    msg (M_FATAL, "ERROR: username from %s authfile '%s' is empty", prefix, auth_file);
+	}
+
+      string_mod (up->username, CC_PRINT, CC_CRLF, 0);
+      string_mod (up->password, CC_PRINT, CC_CRLF, 0);
+
+      up->defined = true;
+    }
+
+#if 0
+  msg (M_INFO, "GET_USER_PASS %s u='%s' p='%s'", prefix, up->username, up->password);
+#endif
+
+  gc_free (&gc);
+
+  return true;
+}
+
+#ifdef ENABLE_CLIENT_CR
+
+/*
+ * See management/management-notes.txt for more info on the
+ * the dynamic challenge/response protocol implemented here.
+ */
+struct auth_challenge_info *
+get_auth_challenge (const char *auth_challenge, struct gc_arena *gc)
+{
+  if (auth_challenge)
+    {
+      struct auth_challenge_info *ac;
+      const int len = strlen (auth_challenge);
+      char *work = (char *) gc_malloc (len+1, false, gc);
+      char *cp;
+
+      struct buffer b;
+      buf_set_read (&b, (const uint8_t *)auth_challenge, len);
+
+      ALLOC_OBJ_CLEAR_GC (ac, struct auth_challenge_info, gc);
+
+      /* parse prefix */
+      if (!buf_parse(&b, ':', work, len))
+	return NULL;
+      if (strcmp(work, "CRV1"))
+	return NULL;
+
+      /* parse flags */
+      if (!buf_parse(&b, ':', work, len))
+	return NULL;
+      for (cp = work; *cp != '\0'; ++cp)
+	{
+	  const char c = *cp;
+	  if (c == 'E')
+	    ac->flags |= CR_ECHO;
+	  else if (c == 'R')
+	    ac->flags |= CR_RESPONSE;
+	}
+      
+      /* parse state ID */
+      if (!buf_parse(&b, ':', work, len))
+	return NULL;
+      ac->state_id = string_alloc(work, gc);
+
+      /* parse user name */
+      if (!buf_parse(&b, ':', work, len))
+	return NULL;
+      ac->user = (char *) gc_malloc (strlen(work)+1, true, gc);
+      openvpn_base64_decode(work, (void*)ac->user, -1);
+
+      /* parse challenge text */
+      ac->challenge_text = string_alloc(BSTR(&b), gc);
+
+      return ac;
+    }
+  else
+    return NULL;
+}
+
+#endif
+
+#if AUTO_USERID
+
+void
+get_user_pass_auto_userid (struct user_pass *up, const char *tag)
+{
+  struct gc_arena gc = gc_new ();
+  struct buffer buf;
+  uint8_t macaddr[6];
+  static uint8_t digest [MD5_DIGEST_LENGTH];
+  static const uint8_t hashprefix[] = "AUTO_USERID_DIGEST";
+
+  const md_kt_t *md5_kt = md_kt_get("MD5");
+  md_ctx_t ctx;
+
+  CLEAR (*up);
+  buf_set_write (&buf, (uint8_t*)up->username, USER_PASS_LEN);
+  buf_printf (&buf, "%s", TARGET_PREFIX);
+  if (get_default_gateway_mac_addr (macaddr))
+    {
+      dmsg (D_AUTO_USERID, "GUPAU: macaddr=%s", format_hex_ex (macaddr, sizeof (macaddr), 0, 1, ":", &gc));
+      md_ctx_init(&ctx, md5_kt);
+      md_ctx_update(&ctx, hashprefix, sizeof (hashprefix) - 1);
+      md_ctx_update(&ctx, macaddr, sizeof (macaddr));
+      md_ctx_final(&ctx, digest);
+      md_ctx_cleanup(&ctx)
+      buf_printf(&buf, "%s", format_hex_ex (digest, sizeof (digest), 0, 256, " ", &gc));
+    }
+  else
+    {
+      buf_printf (&buf, "UNKNOWN");
+    }
+  if (tag && strcmp (tag, "stdin"))
+    buf_printf (&buf, "-%s", tag);
+  up->defined = true;
+  gc_free (&gc);
+
+  dmsg (D_AUTO_USERID, "GUPAU: AUTO_USERID: '%s'", up->username);
+}
+
+#endif
+
+void
+purge_user_pass (struct user_pass *up, const bool force)
+{
+  const bool nocache = up->nocache;
+  static bool warn_shown = false;
+  if (nocache || force)
+    {
+      CLEAR (*up);
+      up->nocache = nocache;
+    }
+  else if (!warn_shown)
+    {
+      msg (M_WARN, "WARNING: this configuration may cache passwords in memory -- use the auth-nocache option to prevent this");
+      warn_shown = true;
+    }
+}
+
+void
+set_auth_token (struct user_pass *up, const char *token)
+{
+  if (token && strlen(token) && up && up->defined && !up->nocache)
+    {
+      CLEAR (up->password);
+      strncpynt (up->password, token, USER_PASS_LEN);
+    }
+}
+
+/*
+ * Process string received by untrusted peer before
+ * printing to console or log file.
+ *
+ * Assumes that string has been null terminated.
+ */
+const char *
+safe_print (const char *str, struct gc_arena *gc)
+{
+  return string_mod_const (str, CC_PRINT, CC_CRLF, '.', gc);
+}
+
+static bool
+is_password_env_var (const char *str)
+{
+  return (strncmp (str, "password", 8) == 0);
+}
+
+bool
+env_allowed (const char *str)
+{
+  return (script_security >= SSEC_PW_ENV || !is_password_env_var (str));
+}
+
+bool
+env_safe_to_print (const char *str)
+{
+#ifndef UNSAFE_DEBUG
+  if (is_password_env_var (str))
+    return false;
+#endif
+  return true;
+}
+
+/* Make arrays of strings */
+
+const char **
+make_env_array (const struct env_set *es,
+		const bool check_allowed,
+		struct gc_arena *gc)
+{
+  char **ret = NULL;
+  struct env_item *e = NULL;
+  int i = 0, n = 0;
+
+  /* figure length of es */
+  if (es)
+    {
+      for (e = es->list; e != NULL; e = e->next)
+	++n;
+    }
+
+  /* alloc return array */
+  ALLOC_ARRAY_CLEAR_GC (ret, char *, n+1, gc);
+
+  /* fill return array */
+  if (es)
+    {
+      i = 0;
+      for (e = es->list; e != NULL; e = e->next)
+	{
+	  if (!check_allowed || env_allowed (e->string))
+	    {
+	      ASSERT (i < n);
+	      ret[i++] = e->string;
+	    }
+	}
+    }
+
+  ret[i] = NULL;
+  return (const char **)ret;
+}
+
+const char **
+make_arg_array (const char *first, const char *parms, struct gc_arena *gc)
+{
+  char **ret = NULL;
+  int base = 0;
+  const int max_parms = MAX_PARMS + 2;
+  int n = 0;
+
+  /* alloc return array */
+  ALLOC_ARRAY_CLEAR_GC (ret, char *, max_parms, gc);
+
+  /* process first parameter, if provided */
+  if (first)
+    {
+      ret[base++] = string_alloc (first, gc);
+    }
+
+  if (parms)
+    {
+      n = parse_line (parms, &ret[base], max_parms - base - 1, "make_arg_array", 0, M_WARN, gc);
+      ASSERT (n >= 0 && n + base + 1 <= max_parms);
+    }
+  ret[base + n] = NULL;
+
+  return (const char **)ret;
+}
+
+static const char **
+make_inline_array (const char *str, struct gc_arena *gc)
+{
+  char line[OPTION_LINE_SIZE];
+  struct buffer buf;
+  int len = 0;
+  char **ret = NULL;
+  int i = 0;
+
+  buf_set_read (&buf, (const uint8_t *) str, strlen (str));
+  while (buf_parse (&buf, '\n', line, sizeof (line)))
+    ++len;
+
+  /* alloc return array */
+  ALLOC_ARRAY_CLEAR_GC (ret, char *, len + 1, gc);
+
+  buf_set_read (&buf, (const uint8_t *) str, strlen(str));
+  while (buf_parse (&buf, '\n', line, sizeof (line)))
+    {
+      chomp (line);
+      ASSERT (i < len);
+      ret[i] = string_alloc (skip_leading_whitespace (line), gc);
+      ++i;
+    }  
+  ASSERT (i <= len);
+  ret[i] = NULL;
+  return (const char **)ret;
+}
+
+static const char **
+make_arg_copy (char **p, struct gc_arena *gc)
+{
+  char **ret = NULL;
+  const int len = string_array_len ((const char **)p);
+  const int max_parms = len + 1;
+  int i;
+
+  /* alloc return array */
+  ALLOC_ARRAY_CLEAR_GC (ret, char *, max_parms, gc);
+
+  for (i = 0; i < len; ++i)
+    ret[i] = p[i];
+
+  return (const char **)ret;
+}
+
+const char **
+make_extended_arg_array (char **p, struct gc_arena *gc)
+{
+  const int argc = string_array_len ((const char **)p);
+  if (!strcmp (p[0], INLINE_FILE_TAG) && argc == 2)
+    return make_inline_array (p[1], gc);
+  else
+  if (argc == 0)
+    return make_arg_array (NULL, NULL, gc);
+  else if (argc == 1)
+    return make_arg_array (p[0], NULL, gc);
+  else if (argc == 2)
+    return make_arg_array (p[0], p[1], gc);
+  else
+    return make_arg_copy (p, gc);
+}
+
+void
+openvpn_sleep (const int n)
+{
+#ifdef ENABLE_MANAGEMENT
+  if (management)
+    {
+      management_event_loop_n_seconds (management, n);
+      return;
+    }
+#endif
+  sleep (n);
+}
+
+/*
+ * Return the next largest power of 2
+ * or u if u is a power of 2.
+ */
+size_t
+adjust_power_of_2 (size_t u)
+{
+  size_t ret = 1;
+
+  while (ret < u)
+    {
+      ret <<= 1;
+      ASSERT (ret > 0);
+    }
+
+  return ret;
+}
+
+/*
+ * A printf-like function (that only recognizes a subset of standard printf
+ * format operators) that prints arguments to an argv list instead
+ * of a standard string.  This is used to build up argv arrays for passing
+ * to execve.
+ */
+
+void
+argv_init (struct argv *a)
+{
+  a->capacity = 0;
+  a->argc = 0;
+  a->argv = NULL;
+  a->system_str = NULL;
+}
+
+struct argv
+argv_new (void)
+{
+  struct argv ret;
+  argv_init (&ret);
+  return ret;
+}
+
+void
+argv_reset (struct argv *a)
+{
+  size_t i;
+  for (i = 0; i < a->argc; ++i)
+    free (a->argv[i]);
+  free (a->argv);
+  free (a->system_str);
+  argv_init (a);
+}
+
+static void
+argv_extend (struct argv *a, const size_t newcap)
+{
+  if (newcap > a->capacity)
+    {
+      char **newargv;
+      size_t i;
+      ALLOC_ARRAY_CLEAR (newargv, char *, newcap);
+      for (i = 0; i < a->argc; ++i)
+	newargv[i] = a->argv[i];
+      free (a->argv);
+      a->argv = newargv;
+      a->capacity = newcap;
+    }
+}
+
+static void
+argv_grow (struct argv *a, const size_t add)
+{
+  const size_t newargc = a->argc + add + 1;
+  ASSERT (newargc > a->argc);
+  argv_extend (a, adjust_power_of_2 (newargc));
+}
+
+static void
+argv_append (struct argv *a, char *str) /* str must have been malloced or be NULL */
+{
+  argv_grow (a, 1);
+  a->argv[a->argc++] = str;
+}
+
+static void
+argv_system_str_append (struct argv *a, const char *str, const bool enquote)
+{
+  if (str)
+    {
+      char *newstr;
+
+      /* compute length of new system_str */
+      size_t l = strlen (str) + 1; /* space for new string plus trailing '\0' */
+      if (a->system_str)
+	l += strlen (a->system_str) + 1; /* space for existing string + space (" ") separator */
+      if (enquote)
+	l += 2; /* space for two quotes */
+
+      /* build new system_str */
+      newstr = (char *) malloc (l);
+      newstr[0] = '\0';
+      check_malloc_return (newstr);
+      if (a->system_str)
+	{
+	  strcpy (newstr, a->system_str);
+	  strcat (newstr, " ");
+	}
+      if (enquote)
+	strcat (newstr, "\"");
+      strcat (newstr, str);
+      if (enquote)
+	strcat (newstr, "\"");
+      free (a->system_str);
+      a->system_str = newstr;
+    }
+}
+
+static char *
+argv_extract_cmd_name (const char *path)
+{
+  if (path)
+    {
+      char *path_cp = strdup(path); /* POSIX basename() implementaions may modify its arguments */
+      const char *bn = basename (path_cp);
+      if (bn)
+	{
+	  char *ret = string_alloc (bn, NULL);
+	  char *dot = strrchr (ret, '.');
+	  if (dot)
+	    *dot = '\0';
+	  free(path_cp);
+	  if (ret[0] != '\0')
+	    return ret;
+	}
+    }
+  return NULL;
+}
+
+const char *
+argv_system_str (const struct argv *a)
+{
+  return a->system_str;
+}
+
+struct argv
+argv_clone (const struct argv *a, const size_t headroom)
+{
+  struct argv r;
+  size_t i;
+
+  argv_init (&r);
+  for (i = 0; i < headroom; ++i)
+    argv_append (&r, NULL);
+  if (a)
+    {
+      for (i = 0; i < a->argc; ++i)
+	argv_append (&r, string_alloc (a->argv[i], NULL));
+      r.system_str = string_alloc (a->system_str, NULL);
+    }
+  return r;
+}
+
+struct argv
+argv_insert_head (const struct argv *a, const char *head)
+{
+  struct argv r;
+  char *s;
+
+  r = argv_clone (a, 1);
+  r.argv[0] = string_alloc (head, NULL);
+  s = r.system_str;
+  r.system_str = string_alloc (head, NULL);
+  if (s)
+    {
+      argv_system_str_append (&r, s, false);
+      free (s);
+    }
+  return r;
+}
+
+char *
+argv_term (const char **f)
+{
+  const char *p = *f;
+  const char *term = NULL;
+  size_t termlen = 0;
+
+  if (*p == '\0')
+    return NULL;
+
+  while (true)
+    {
+      const int c = *p;
+      if (c == '\0')
+	break;
+      if (term)
+	{
+	  if (!isspace (c))
+	    ++termlen;
+	  else
+	    break;
+	}
+      else
+	{
+	  if (!isspace (c))
+	    {
+	      term = p;
+	      termlen = 1;
+	    }
+	}
+      ++p;
+    }
+  *f = p;
+
+  if (term)
+    {
+      char *ret;
+      ASSERT (termlen > 0);
+      ret = malloc (termlen + 1);
+      check_malloc_return (ret);
+      memcpy (ret, term, termlen);
+      ret[termlen] = '\0';
+      return ret;
+    }
+  else
+    return NULL;
+}
+
+const char *
+argv_str (const struct argv *a, struct gc_arena *gc, const unsigned int flags)
+{
+  if (a->argv)
+    return print_argv ((const char **)a->argv, gc, flags);
+  else
+    return "";
+}
+
+void
+argv_msg (const int msglev, const struct argv *a)
+{
+  struct gc_arena gc = gc_new ();
+  msg (msglev, "%s", argv_str (a, &gc, 0));
+  gc_free (&gc);
+}
+
+void
+argv_msg_prefix (const int msglev, const struct argv *a, const char *prefix)
+{
+  struct gc_arena gc = gc_new ();
+  msg (msglev, "%s: %s", prefix, argv_str (a, &gc, 0));
+  gc_free (&gc);
+}
+
+void
+argv_printf (struct argv *a, const char *format, ...)
+{
+  va_list arglist;
+  va_start (arglist, format);
+  argv_printf_arglist (a, format, 0, arglist);
+  va_end (arglist);
+ }
+
+void
+argv_printf_cat (struct argv *a, const char *format, ...)
+{
+  va_list arglist;
+  va_start (arglist, format);
+  argv_printf_arglist (a, format, APA_CAT, arglist);
+  va_end (arglist);
+}
+
+void
+argv_printf_arglist (struct argv *a, const char *format, const unsigned int flags, va_list arglist)
+{
+  struct gc_arena gc = gc_new ();
+  char *term;
+  const char *f = format;
+
+  if (!(flags & APA_CAT))
+    argv_reset (a);
+  argv_extend (a, 1); /* ensure trailing NULL */
+
+  while ((term = argv_term (&f)) != NULL) 
+    {
+      if (term[0] == '%')
+	{
+	  if (!strcmp (term, "%s"))
+	    {
+	      char *s = va_arg (arglist, char *);
+	      if (!s)
+		s = "";
+	      argv_append (a, string_alloc (s, NULL));
+	      argv_system_str_append (a, s, true);
+	    }
+	  else if (!strcmp (term, "%sc"))
+	    {
+	      char *s = va_arg (arglist, char *);
+	      if (s)
+		{
+		  int nparms;
+		  char *parms[MAX_PARMS+1];
+		  int i;
+
+		  nparms = parse_line (s, parms, MAX_PARMS, "SCRIPT-ARGV", 0, D_ARGV_PARSE_CMD, &gc);
+		  if (nparms)
+		    {
+		      for (i = 0; i < nparms; ++i)
+			argv_append (a, string_alloc (parms[i], NULL));
+		    }
+		  else
+		    argv_append (a, string_alloc (s, NULL));
+
+		  argv_system_str_append (a, s, false);
+		}
+	      else
+		{
+		  argv_append (a, string_alloc ("", NULL));
+		  argv_system_str_append (a, "echo", false);
+		}
+	    }
+	  else if (!strcmp (term, "%d"))
+	    {
+	      char numstr[64];
+	      openvpn_snprintf (numstr, sizeof (numstr), "%d", va_arg (arglist, int));
+	      argv_append (a, string_alloc (numstr, NULL));
+	      argv_system_str_append (a, numstr, false);
+	    }
+	  else if (!strcmp (term, "%u"))
+	    {
+	      char numstr[64];
+	      openvpn_snprintf (numstr, sizeof (numstr), "%u", va_arg (arglist, unsigned int));
+	      argv_append (a, string_alloc (numstr, NULL));
+	      argv_system_str_append (a, numstr, false);
+	    }
+	  else if (!strcmp (term, "%s/%d"))
+	    {
+	      char numstr[64];
+	      char *s = va_arg (arglist, char *);
+
+	      if (!s)
+		s = "";
+
+	      openvpn_snprintf (numstr, sizeof (numstr), "%d", va_arg (arglist, int));
+
+	      {
+		const size_t len = strlen(s) + strlen(numstr) + 2;
+		char *combined = (char *) malloc (len);
+		check_malloc_return (combined);
+
+		strcpy (combined, s);
+		strcat (combined, "/");
+		strcat (combined, numstr);
+		argv_append (a, combined);
+		argv_system_str_append (a, combined, false);
+	      }
+	    }
+	  else if (!strcmp (term, "%s%sc"))
+	    {
+	      char *s1 = va_arg (arglist, char *);
+	      char *s2 = va_arg (arglist, char *);
+	      char *combined;
+	      char *cmd_name;
+
+	      if (!s1) s1 = "";
+	      if (!s2) s2 = "";
+	      combined = (char *) malloc (strlen(s1) + strlen(s2) + 1);
+	      check_malloc_return (combined);
+	      strcpy (combined, s1);
+	      strcat (combined, s2);
+	      argv_append (a, combined);
+
+	      cmd_name = argv_extract_cmd_name (combined);
+	      if (cmd_name)
+		{
+		  argv_system_str_append (a, cmd_name, false);
+		  free (cmd_name);
+		}
+	    }
+	  else
+	    ASSERT (0);
+	  free (term);
+	}
+      else
+	{
+	  argv_append (a, term);
+	  argv_system_str_append (a, term, false);
+	}
+    }
+  gc_free (&gc);
+}
+
+#ifdef ARGV_TEST
+void
+argv_test (void)
+{
+  struct gc_arena gc = gc_new ();
+  const char *s;
+
+  struct argv a;
+
+  argv_init (&a);
+  argv_printf (&a, "%sc foo bar %s", "c:\\\\src\\\\test\\\\jyargs.exe", "foo bar");
+  argv_msg_prefix (M_INFO, &a, "ARGV");
+  msg (M_INFO, "ARGV-S: %s", argv_system_str(&a));
+  /*openvpn_execve_check (&a, NULL, 0, "command failed");*/
+
+  argv_printf (&a, "%sc %s %s", "c:\\\\src\\\\test files\\\\batargs.bat", "foo", "bar");  
+  argv_msg_prefix (M_INFO, &a, "ARGV");
+  msg (M_INFO, "ARGV-S: %s", argv_system_str(&a));
+  /*openvpn_execve_check (&a, NULL, 0, "command failed");*/
+
+  argv_printf (&a, "%s%sc foo bar %s %s/%d %d %u", "/foo", "/bar.exe", "one two", "1.2.3.4", 24, -69, 96);
+  argv_msg_prefix (M_INFO, &a, "ARGV");
+  msg (M_INFO, "ARGV-S: %s", argv_system_str(&a));
+  /*openvpn_execve_check (&a, NULL, 0, "command failed");*/
+
+  argv_printf (&a, "this is a %s test of int %d unsigned %u", "FOO", -69, 42);
+  s = argv_str (&a, &gc, PA_BRACKET);
+  printf ("PF: %s\n", s);
+  printf ("PF-S: %s\n", argv_system_str(&a));
+
+  {
+    struct argv b = argv_insert_head (&a, "MARK");
+    s = argv_str (&b, &gc, PA_BRACKET);
+    printf ("PF: %s\n", s);
+    printf ("PF-S: %s\n", argv_system_str(&b));
+    argv_reset (&b);
+  }
+
+  argv_printf (&a, "%sc foo bar %d", "\"multi term\" command      following \\\"spaces", 99);
+  s = argv_str (&a, &gc, PA_BRACKET);
+  printf ("PF: %s\n", s);
+  printf ("PF-S: %s\n", argv_system_str(&a));
+  argv_reset (&a);
+
+  s = argv_str (&a, &gc, PA_BRACKET);
+  printf ("PF: %s\n", s);
+  printf ("PF-S: %s\n", argv_system_str(&a));
+  argv_reset (&a);
+
+  argv_printf (&a, "foo bar %d", 99);
+  argv_printf_cat (&a, "bar %d foo %sc", 42, "nonesuch");
+  argv_printf_cat (&a, "cool %s %d u %s/%d end", "frood", 4, "hello", 7);
+  s = argv_str (&a, &gc, PA_BRACKET);
+  printf ("PF: %s\n", s);
+  printf ("PF-S: %s\n", argv_system_str(&a));
+  argv_reset (&a);
+
+#if 0
+  {
+    char line[512];
+    while (fgets (line, sizeof(line), stdin) != NULL)
+      {
+	char *term;
+	const char *f = line;
+	int i = 0;
+
+	while ((term = argv_term (&f)) != NULL) 
+	  {
+	    printf ("[%d] '%s'\n", i, term);
+	    ++i;
+	    free (term);
+	  }
+      }
+  }
+#endif
+
+  argv_reset (&a);
+  gc_free (&gc);
+}
+#endif
+
+/*
+ * Remove security-sensitive strings from control message
+ * so that they will not be output to log file.
+ */
+const char *
+sanitize_control_message(const char *src, struct gc_arena *gc)
+{
+  char *ret = gc_malloc (strlen(src)+1, false, gc);
+  char *dest = ret;
+  bool redact = false;
+  int skip = 0;
+
+  for (;;)
+    {
+      const char c = *src;
+      if (c == '\0')
+	  break;
+      if (c == 'S' && !strncmp(src, "SESS_ID_", 8))
+	{
+	  skip = 7;
+	  redact = true;
+	}
+      else if (c == 'e' && !strncmp(src, "echo ", 5))
+	{
+	  skip = 4;
+	  redact = true;
+	}
+
+      if (c == ',') /* end of redacted item? */
+	{
+	  skip = 0;
+	  redact = false;
+	}
+
+      if (redact)
+	{
+	  if (skip > 0)
+	    {
+	      --skip;
+	      *dest++ = c;
+	    }
+	}
+      else
+	*dest++ = c;
+
+      ++src;
+    }
+  *dest = '\0';
+  return ret;
+}
+
+/**
+ * Will set or query for a global compat flag.  To modify the compat flags
+ * the COMPAT_FLAG_SET must be bitwise ORed together with the flag to set.
+ * If no "operator" flag is given it defaults to COMPAT_FLAG_QUERY,
+ * which returns the flag state.
+ *
+ * @param  flag  Flag to be set/queried for bitwise ORed with the operator flag
+ * @return Returns 0 if the flag is not set, otherwise the 'flag' value is returned
+ */
+bool
+compat_flag (unsigned int flag)
+{
+  static unsigned int compat_flags = 0;
+
+  if (flag & COMPAT_FLAG_SET)
+    compat_flags |= (flag >> 1);
+
+  return (compat_flags & (flag >> 1));
+
+}