summaryrefslogtreecommitdiff
path: root/src/openvpn/console.c
blob: 86331a11c23ce8021bb7965ff3d77141a69fc6e5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
/*
 *  OpenVPN -- An application to securely tunnel IP networks
 *             over a single 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 "console.h"
#include "error.h"
#include "buffer.h"
#include "misc.h"

#ifdef ENABLE_SYSTEMD
#include <systemd/sd-daemon.h>
#endif

#ifdef WIN32

#include "win32.h"

/*
 * Get input from console.
 *
 * Return false on input error, or if service
 * exit event is signaled.
 */

static bool
get_console_input_win32 (const char *prompt, const bool echo, char *input, const int capacity)
{
  HANDLE in = INVALID_HANDLE_VALUE;
  HANDLE err = INVALID_HANDLE_VALUE;
  DWORD len = 0;

  ASSERT (prompt);
  ASSERT (input);
  ASSERT (capacity > 0);

  input[0] = '\0';

  in = GetStdHandle (STD_INPUT_HANDLE);
  err = get_orig_stderr ();

  if (in != INVALID_HANDLE_VALUE
      && err != INVALID_HANDLE_VALUE
      && !win32_service_interrupt (&win32_signal)
      && WriteFile (err, prompt, strlen (prompt), &len, NULL))
    {
      bool is_console = (GetFileType (in) == FILE_TYPE_CHAR);
      DWORD flags_save = 0;
      int status = 0;
      WCHAR *winput;

      if (is_console)
	{
	  if (GetConsoleMode (in, &flags_save))
	    {
	      DWORD flags = ENABLE_LINE_INPUT | ENABLE_PROCESSED_INPUT;
	      if (echo)
		flags |= ENABLE_ECHO_INPUT;
	      SetConsoleMode (in, flags);
	    }
	  else
	    is_console = 0;
	}

      if (is_console)
        {
          winput = malloc (capacity * sizeof (WCHAR));
          if (winput == NULL)
            return false;

          status = ReadConsoleW (in, winput, capacity, &len, NULL);
          WideCharToMultiByte (CP_UTF8, 0, winput, len, input, capacity, NULL, NULL);
          free (winput);
        }
      else
        status = ReadFile (in, input, capacity, &len, NULL);

      string_null_terminate (input, (int)len, capacity);
      chomp (input);

      if (!echo)
	WriteFile (err, "\r\n", 2, &len, NULL);
      if (is_console)
	SetConsoleMode (in, flags_save);
      if (status && !win32_service_interrupt (&win32_signal))
	return true;
    }

  return false;
}

#endif

#ifdef HAVE_GETPASS

static FILE *
open_tty (const bool write)
{
  FILE *ret;
  ret = fopen ("/dev/tty", write ? "w" : "r");
  if (!ret)
    ret = write ? stderr : stdin;
  return ret;
}

static void
close_tty (FILE *fp)
{
  if (fp != stderr && fp != stdin)
    fclose (fp);
}

#endif

#ifdef ENABLE_SYSTEMD

/*
 * is systemd running
 */

static bool
check_systemd_running ()
{
  struct stat c;

  /* We simply test whether the systemd cgroup hierarchy is
   * mounted, as well as the systemd-ask-password executable
   * being available */

  return (sd_booted() > 0)
	  && (stat(SYSTEMD_ASK_PASSWORD_PATH, &c) == 0);

}

static bool
get_console_input_systemd (const char *prompt, const bool echo, char *input, const int capacity)
{
  int std_out;
  bool ret = false;
  struct argv argv;

  argv_init (&argv);
  argv_printf (&argv, SYSTEMD_ASK_PASSWORD_PATH);
  argv_printf_cat (&argv, "%s", prompt);

  if ((std_out = openvpn_popen (&argv, NULL)) < 0) {
	  return false;
  }

  memset (input, 0, capacity);
  if (read (std_out, input, capacity-1) > 0)
    {
       chomp (input);
       ret = true;
    }
  close (std_out);

  argv_reset (&argv);

  return ret;
}


#endif

/*
 * Get input from console
 */
bool
get_console_input (const char *prompt, const bool echo, char *input, const int capacity)
{
  bool ret = false;
  ASSERT (prompt);
  ASSERT (input);
  ASSERT (capacity > 0);
  input[0] = '\0';

#ifdef ENABLE_SYSTEMD
  if (check_systemd_running ())
    return get_console_input_systemd (prompt, echo, input, capacity);
#endif

#if defined(WIN32)
  return get_console_input_win32 (prompt, echo, input, capacity);
#elif defined(HAVE_GETPASS)

  /* did we --daemon'ize before asking for passwords?
   * (in which case neither stdin or stderr are connected to a tty and
   * /dev/tty can not be open()ed anymore)
   */
  if ( !isatty(0) && !isatty(2) )
    {
      int fd = open( "/dev/tty", O_RDWR );
      if ( fd < 0 )
	{ msg(M_FATAL, "neither stdin nor stderr are a tty device and you have neither a controlling tty nor systemd - can't ask for '%s'.  If you used --daemon, you need to use --askpass to make passphrase-protected keys work, and you can not use --auth-nocache.", prompt ); }
      close(fd);
    }

  if (echo)
    {
      FILE *fp;

      fp = open_tty (true);
      fprintf (fp, "%s", prompt);
      fflush (fp);
      close_tty (fp);

      fp = open_tty (false);
      if (fgets (input, capacity, fp) != NULL)
	{
	  chomp (input);
	  ret = true;
	}
      close_tty (fp);
    }
  else
    {
      char *gp = getpass (prompt);
      if (gp)
	{
	  strncpynt (input, gp, capacity);
	  memset (gp, 0, strlen (gp));
	  ret = true;
	}
    }
#else
  msg (M_FATAL, "Sorry, but I can't get console input on this OS (%s)", prompt);
#endif
  return ret;
}