/*-

 * Copyright (c) 2014 Michihiro NAKAJIMA

 * 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

 *    in this position and unchanged.

 * 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.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``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(S) 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.

 */

/*	$OpenBSD: readpassphrase.c,v 1.22 2010/01/13 10:20:54 dtucker Exp $	*/

/*

 * Copyright (c) 2000-2002, 2007 Todd C. Miller <Todd.Miller@courtesan.com>

 *

 * Permission to use, copy, modify, and distribute this software for any

 * purpose with or without fee is hereby granted, provided that the above

 * copyright notice and this permission notice appear in all copies.

 *

 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES

 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF

 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR

 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN

 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF

 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

 *

 * Sponsored in part by the Defense Advanced Research Projects

 * Agency (DARPA) and Air Force Research Laboratory, Air Force

 * Materiel Command, USAF, under agreement number F39502-99-1-0512.

 */

/* OPENBSD ORIGINAL: lib/libc/gen/readpassphrase.c */

#include "lafe_platform.h"

__FBSDID("$FreeBSD$");

#include <errno.h>

#ifdef HAVE_STDLIB_H

#include <stdlib.h>

#endif

#ifdef HAVE_UNISTD_H

#include <unistd.h>

#endif

#ifdef HAVE_READPASSPHRASE_H

#include <readpassphrase.h>

#endif

#include "err.h"

#include "passphrase.h"

#ifndef HAVE_READPASSPHRASE

#define RPP_ECHO_OFF    0x00		/* Turn off echo (default). */

#define RPP_ECHO_ON     0x01		/* Leave echo on. */

#define RPP_REQUIRE_TTY 0x02		/* Fail if there is no tty. */

#define RPP_FORCELOWER  0x04		/* Force input to lower case. */

#define RPP_FORCEUPPER  0x08		/* Force input to upper case. */

#define RPP_SEVENBIT    0x10		/* Strip the high bit from input. */

#define RPP_STDIN       0x20		/* Read from stdin, not /dev/tty */

#if defined(_WIN32) && !defined(__CYGWIN__)

#include <windows.h>

static char *

readpassphrase(const char *prompt, char *buf, size_t bufsiz, int flags)

{

	HANDLE hStdin, hStdout;

	DWORD mode, rbytes;

	BOOL success;

	(void)flags;

	hStdin = GetStdHandle(STD_INPUT_HANDLE);

	if (hStdin == INVALID_HANDLE_VALUE)

		return (NULL);

	hStdout = GetStdHandle(STD_OUTPUT_HANDLE);

	if (hStdout == INVALID_HANDLE_VALUE)

		return (NULL);

	success = GetConsoleMode(hStdin, &mode);

	if (!success)

		return (NULL);

	mode &= ~ENABLE_ECHO_INPUT;

	mode |= ENABLE_LINE_INPUT | ENABLE_PROCESSED_INPUT;

	success = SetConsoleMode(hStdin, mode);

	if (!success)

		return (NULL);

	success = WriteFile(hStdout, prompt, (DWORD)strlen(prompt),

		NULL, NULL);

	if (!success)

		return (NULL);

	success = ReadFile(hStdin, buf, (DWORD)bufsiz - 1, &rbytes, NULL);

	if (!success)

		return (NULL);

	WriteFile(hStdout, "\r\n", 2, NULL, NULL);

	buf[rbytes] = '\0';

	/* Remove trailing carriage return(s). */

	if (rbytes > 2 && buf[rbytes - 2] == '\r' && buf[rbytes - 1] == '\n')

		buf[rbytes - 2] = '\0';

	return (buf);

}

#else /* _WIN32 && !__CYGWIN__ */

#include <assert.h>

#include <ctype.h>

#include <fcntl.h>

#ifdef HAVE_PATHS_H

#include <paths.h>

#endif

#include <signal.h>

#include <string.h>

#include <termios.h>

#include <unistd.h>

#ifndef _PATH_TTY

#define _PATH_TTY "/dev/tty"

#endif

#ifdef TCSASOFT

# define _T_FLUSH	(TCSAFLUSH|TCSASOFT)

#else

# define _T_FLUSH	(TCSAFLUSH)

#endif

/* SunOS 4.x which lacks _POSIX_VDISABLE, but has VDISABLE */

#if !defined(_POSIX_VDISABLE) && defined(VDISABLE)

#  define _POSIX_VDISABLE       VDISABLE

#endif

#define M(a,b) (a > b ? a : b)

#define MAX_SIGNO M(M(M(SIGALRM, SIGHUP), \

                      M(SIGINT, SIGPIPE)), \

                    M(M(SIGQUIT, SIGTERM), \

                      M(M(SIGTSTP, SIGTTIN), SIGTTOU)))

static volatile sig_atomic_t signo[MAX_SIGNO + 1];

static void

handler(int s)

{

	assert(s <= MAX_SIGNO);

	signo[s] = 1;

}

static char *

readpassphrase(const char *prompt, char *buf, size_t bufsiz, int flags)

{

	ssize_t nr;

	int input, output, save_errno, i, need_restart;

	char ch, *p, *end;

	struct termios term, oterm;

	struct sigaction sa, savealrm, saveint, savehup, savequit, saveterm;

	struct sigaction savetstp, savettin, savettou, savepipe;

	/* I suppose we could alloc on demand in this case (XXX). */

	if (bufsiz == 0) {

		errno = EINVAL;

		return(NULL);

	}

restart:

	for (i = 0; i <= MAX_SIGNO; i++)

		signo[i] = 0;

	nr = -1;

	save_errno = 0;

	need_restart = 0;

	/*

	 * Read and write to /dev/tty if available.  If not, read from

	 * stdin and write to stderr unless a tty is required.

	 */

	if ((flags & RPP_STDIN) ||

	    (input = output = open(_PATH_TTY, O_RDWR)) == -1) {

		if (flags & RPP_REQUIRE_TTY) {

			errno = ENOTTY;

			return(NULL);

		}

		input = STDIN_FILENO;

		output = STDERR_FILENO;

	}

	/*

	 * Catch signals that would otherwise cause the user to end

	 * up with echo turned off in the shell.  Don't worry about

	 * things like SIGXCPU and SIGVTALRM for now.

	 */

	sigemptyset(&sa.sa_mask);

	sa.sa_flags = 0;		/* don't restart system calls */

	sa.sa_handler = handler;

	/* Keep this list in sync with MAX_SIGNO! */

	(void)sigaction(SIGALRM, &sa, &savealrm);

	(void)sigaction(SIGHUP, &sa, &savehup);

	(void)sigaction(SIGINT, &sa, &saveint);

	(void)sigaction(SIGPIPE, &sa, &savepipe);

	(void)sigaction(SIGQUIT, &sa, &savequit);

	(void)sigaction(SIGTERM, &sa, &saveterm);

	(void)sigaction(SIGTSTP, &sa, &savetstp);

	(void)sigaction(SIGTTIN, &sa, &savettin);

	(void)sigaction(SIGTTOU, &sa, &savettou);

	/* Turn off echo if possible. */

	if (input != STDIN_FILENO && tcgetattr(input, &oterm) == 0) {

		memcpy(&term, &oterm, sizeof(term));

		if (!(flags & RPP_ECHO_ON))

			term.c_lflag &= ~(ECHO | ECHONL);

#ifdef VSTATUS

		if (term.c_cc[VSTATUS] != _POSIX_VDISABLE)

			term.c_cc[VSTATUS] = _POSIX_VDISABLE;

#endif

		(void)tcsetattr(input, _T_FLUSH, &term);

	} else {

		memset(&term, 0, sizeof(term));

		term.c_lflag |= ECHO;

		memset(&oterm, 0, sizeof(oterm));

		oterm.c_lflag |= ECHO;

	}

	/* No I/O if we are already backgrounded. */

	if (signo[SIGTTOU] != 1 && signo[SIGTTIN] != 1) {

		if (!(flags & RPP_STDIN)) {

			int r = write(output, prompt, strlen(prompt));

			(void)r;

		}

		end = buf + bufsiz - 1;

		p = buf;

		while ((nr = read(input, &ch, 1)) == 1 && ch != '\n' && ch != '\r') {

			if (p < end) {

				if ((flags & RPP_SEVENBIT))

					ch &= 0x7f;

				if (isalpha((unsigned char)ch)) {

					if ((flags & RPP_FORCELOWER))

						ch = (char)tolower((unsigned char)ch);

					if ((flags & RPP_FORCEUPPER))

						ch = (char)toupper((unsigned char)ch);

				}

				*p++ = ch;

			}

		}

		*p = '\0';

		save_errno = errno;

		if (!(term.c_lflag & ECHO)) {

			int r = write(output, "\n", 1);

			(void)r;

		}

	}

	/* Restore old terminal settings and signals. */

	if (memcmp(&term, &oterm, sizeof(term)) != 0) {

		while (tcsetattr(input, _T_FLUSH, &oterm) == -1 &&

		    errno == EINTR)

			continue;

	}

	(void)sigaction(SIGALRM, &savealrm, NULL);

	(void)sigaction(SIGHUP, &savehup, NULL);

	(void)sigaction(SIGINT, &saveint, NULL);

	(void)sigaction(SIGQUIT, &savequit, NULL);

	(void)sigaction(SIGPIPE, &savepipe, NULL);

	(void)sigaction(SIGTERM, &saveterm, NULL);

	(void)sigaction(SIGTSTP, &savetstp, NULL);

	(void)sigaction(SIGTTIN, &savettin, NULL);

	(void)sigaction(SIGTTOU, &savettou, NULL);

	if (input != STDIN_FILENO)

		(void)close(input);

	/*

	 * If we were interrupted by a signal, resend it to ourselves

	 * now that we have restored the signal handlers.

	 */

	for (i = 0; i <= MAX_SIGNO; i++) {

		if (signo[i]) {

			kill(getpid(), i);

			switch (i) {

			case SIGTSTP:

			case SIGTTIN:

			case SIGTTOU:

				need_restart = 1;

			}

		}

	}

	if (need_restart)

		goto restart;

	if (save_errno)

		errno = save_errno;

	return(nr == -1 ? NULL : buf);

}

#endif /* _WIN32 && !__CYGWIN__ */

#endif /* HAVE_READPASSPHRASE */

char *

lafe_readpassphrase(const char *prompt, char *buf, size_t bufsiz)

{

	char *p;

	p = readpassphrase(prompt, buf, bufsiz, RPP_ECHO_OFF);

	if (p == NULL) {

		switch (errno) {

		case EINTR:

			break;

		default:

			lafe_errc(1, errno, "Couldn't read passphrase");

			break;

		}

	}

	return (p);

}