/* $OpenBSD: ui_openssl.c,v 1.25 2015/09/10 15:56:26 jsing Exp $ */

/* Written by Richard Levitte (richard@levitte.org) and others

 * for the OpenSSL project 2001.

 */

/* ====================================================================

 * Copyright (c) 2001 The OpenSSL Project.  All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 *

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in

 *    the documentation and/or other materials provided with the

 *    distribution.

 *

 * 3. All advertising materials mentioning features or use of this

 *    software must display the following acknowledgment:

 *    "This product includes software developed by the OpenSSL Project

 *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"

 *

 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to

 *    endorse or promote products derived from this software without

 *    prior written permission. For written permission, please contact

 *    openssl-core@openssl.org.

 *

 * 5. Products derived from this software may not be called "OpenSSL"

 *    nor may "OpenSSL" appear in their names without prior written

 *    permission of the OpenSSL Project.

 *

 * 6. Redistributions of any form whatsoever must retain the following

 *    acknowledgment:

 *    "This product includes software developed by the OpenSSL Project

 *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"

 *

 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY

 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR

 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT

 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,

 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED

 * OF THE POSSIBILITY OF SUCH DAMAGE.

 * ====================================================================

 *

 * This product includes cryptographic software written by Eric Young

 * (eay@cryptsoft.com).  This product includes software written by Tim

 * Hudson (tjh@cryptsoft.com).

 *

 */

/* The lowest level part of this file was previously in crypto/des/read_pwd.c,

 * Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)

 * All rights reserved.

 *

 * This package is an SSL implementation written

 * by Eric Young (eay@cryptsoft.com).

 * The implementation was written so as to conform with Netscapes SSL.

 *

 * This library is free for commercial and non-commercial use as long as

 * the following conditions are aheared to.  The following conditions

 * apply to all code found in this distribution, be it the RC4, RSA,

 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation

 * included with this distribution is covered by the same copyright terms

 * except that the holder is Tim Hudson (tjh@cryptsoft.com).

 *

 * Copyright remains Eric Young's, and as such any Copyright notices in

 * the code are not to be removed.

 * If this package is used in a product, Eric Young should be given attribution

 * as the author of the parts of the library used.

 * This can be in the form of a textual message at program startup or

 * in documentation (online or textual) provided with the package.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 3. All advertising materials mentioning features or use of this software

 *    must display the following acknowledgement:

 *    "This product includes cryptographic software written by

 *     Eric Young (eay@cryptsoft.com)"

 *    The word 'cryptographic' can be left out if the rouines from the library

 *    being used are not cryptographic related :-).

 * 4. If you include any Windows specific code (or a derivative thereof) from

 *    the apps directory (application code) you must include an acknowledgement:

 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"

 *

 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 *

 * The licence and distribution terms for any publically available version or

 * derivative of this code cannot be changed.  i.e. this code cannot simply be

 * copied and put under another distribution licence

 * [including the GNU Public Licence.]

 */

#include <sys/ioctl.h>

#include <openssl/opensslconf.h>

#include <errno.h>

#include <signal.h>

#include <stdio.h>

#include <string.h>

#include <termios.h>

#include <unistd.h>

#include "ui_locl.h"

#ifndef NX509_SIG

#define NX509_SIG 32

#endif

/* Define globals.  They are protected by a lock */

static struct sigaction savsig[NX509_SIG];

static struct termios tty_orig;

static FILE *tty_in, *tty_out;

static int is_a_tty;

/* Declare static functions */

static int read_till_nl(FILE *);

static void recsig(int);

static void pushsig(void);

static void popsig(void);

static int read_string_inner(UI *ui, UI_STRING *uis, int echo, int strip_nl);

static int read_string(UI *ui, UI_STRING *uis);

static int write_string(UI *ui, UI_STRING *uis);

static int open_console(UI *ui);

static int echo_console(UI *ui);

static int noecho_console(UI *ui);

static int close_console(UI *ui);

static UI_METHOD ui_openssl = {

  .name = "OpenSSL default user interface",

  .ui_open_session = open_console,

  .ui_write_string = write_string,

  .ui_read_string = read_string,

  .ui_close_session = close_console,

};

/* The method with all the built-in thingies */

UI_METHOD *

UI_OpenSSL(void)

{

  return &ui_openssl;

}

/* The following function makes sure that info and error strings are printed

   before any prompt. */

static int

write_string(UI *ui, UI_STRING *uis)

{

  switch (UI_get_string_type(uis)) {

  case UIT_ERROR:

  case UIT_INFO:

    fputs(UI_get0_output_string(uis), tty_out);

    fflush(tty_out);

    break;

  default:

    break;

  }

  return 1;

}

static int

read_string(UI *ui, UI_STRING *uis)

{

  int ok = 0;

  switch (UI_get_string_type(uis)) {

  case UIT_BOOLEAN:

    fputs(UI_get0_output_string(uis), tty_out);

    fputs(UI_get0_action_string(uis), tty_out);

    fflush(tty_out);

    return read_string_inner(ui, uis,

        UI_get_input_flags(uis) & UI_INPUT_FLAG_ECHO, 0);

  case UIT_PROMPT:

    fputs(UI_get0_output_string(uis), tty_out);

    fflush(tty_out);

    return read_string_inner(ui, uis,

        UI_get_input_flags(uis) & UI_INPUT_FLAG_ECHO, 1);

  case UIT_VERIFY:

    fprintf(tty_out, "Verifying - %s",

        UI_get0_output_string(uis));

    fflush(tty_out);

    if ((ok = read_string_inner(ui, uis, UI_get_input_flags(uis) &

        UI_INPUT_FLAG_ECHO, 1)) <= 0)

      return ok;

    if (strcmp(UI_get0_result_string(uis),

        UI_get0_test_string(uis)) != 0) {

      fprintf(tty_out, "Verify failure\n");

      fflush(tty_out);

      return 0;

    }

    break;

  default:

    break;

  }

  return 1;

}

/* Internal functions to read a string without echoing */

static int

read_till_nl(FILE *in)

{

#define SIZE 4

  char buf[SIZE + 1];

  do {

    if (!fgets(buf, SIZE, in))

      return 0;

  } while (strchr(buf, '\n') == NULL);

  return 1;

}

static volatile sig_atomic_t intr_signal;

static int

read_string_inner(UI *ui, UI_STRING *uis, int echo, int strip_nl)

{

  static int ps;

  int ok;

  char result[BUFSIZ];

  int maxsize = BUFSIZ - 1;

  char *p;

  intr_signal = 0;

  ok = 0;

  ps = 0;

  pushsig();

  ps = 1;

  if (!echo && !noecho_console(ui))

    goto error;

  ps = 2;

  result[0] = '\0';

  p = fgets(result, maxsize, tty_in);

  if (!p)

    goto error;

  if (feof(tty_in))

    goto error;

  if (ferror(tty_in))

    goto error;

  if ((p = strchr(result, '\n')) != NULL) {

    if (strip_nl)

      *p = '\0';

  } else if (!read_till_nl(tty_in))

    goto error;

  if (UI_set_result(ui, uis, result) >= 0)

    ok = 1;

error:

  if (intr_signal == SIGINT)

    ok = -1;

  if (!echo)

    fprintf(tty_out, "\n");

  if (ps >= 2 && !echo && !echo_console(ui))

    ok = 0;

  if (ps >= 1)

    popsig();

  explicit_bzero(result, BUFSIZ);

  return ok;

}

/* Internal functions to open, handle and close a channel to the console.  */

static int

open_console(UI *ui)

{

  CRYPTO_w_lock(CRYPTO_LOCK_UI);

  is_a_tty = 1;

#define DEV_TTY "/dev/tty"

  if ((tty_in = fopen(DEV_TTY, "r")) == NULL)

    tty_in = stdin;

  if ((tty_out = fopen(DEV_TTY, "w")) == NULL)

    tty_out = stderr;

  if (tcgetattr(fileno(tty_in), &tty_orig) == -1) {

    if (errno == ENOTTY)

      is_a_tty = 0;

    else

      /*

       * Ariel Glenn ariel@columbia.edu reports that

       * solaris can return EINVAL instead.  This should be

       * ok

       */

      if (errno == EINVAL)

        is_a_tty = 0;

    else

      return 0;

  }

  return 1;

}

static int

noecho_console(UI *ui)

{

  struct termios tty_new = tty_orig;

  tty_new.c_lflag &= ~ECHO;

  if (is_a_tty && (tcsetattr(fileno(tty_in), TCSANOW, &tty_new) == -1))

    return 0;

  return 1;

}

static int

echo_console(UI *ui)

{

  if (is_a_tty && (tcsetattr(fileno(tty_in), TCSANOW, &tty_orig) == -1))

    return 0;

  return 1;

}

static int

close_console(UI *ui)

{

  if (tty_in != stdin)

    fclose(tty_in);

  if (tty_out != stderr)

    fclose(tty_out);

  CRYPTO_w_unlock(CRYPTO_LOCK_UI);

  return 1;

}

/* Internal functions to handle signals and act on them */

static void

pushsig(void)

{

  int i;

  struct sigaction sa;

  memset(&sa, 0, sizeof sa);

  sa.sa_handler = recsig;

  for (i = 1; i < NX509_SIG; i++) {

    if (i == SIGUSR1)

      continue;

    if (i == SIGUSR2)

      continue;

    if (i == SIGKILL) /* We can't make any action on that. */

      continue;

    sigaction(i, &sa, &savsig[i]);

  }

  signal(SIGWINCH, SIG_DFL);

}

static void

popsig(void)

{

  int i;

  for (i = 1; i < NX509_SIG; i++) {

    if (i == SIGUSR1)

      continue;

    if (i == SIGUSR2)

      continue;

    sigaction(i, &savsig[i], NULL);

  }

}

static void

recsig(int i)

{

  intr_signal = i;

}