FreeRDP/libfreerdp/utils/passphrase.c

/**
 * FreeRDP: A Remote Desktop Protocol Implementation
 * Passphrase Handling Utils
 *
 * Copyright 2011 Shea Levy <shea@shealevy.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <freerdp/config.h>

#include <errno.h>
#include <freerdp/utils/passphrase.h>

#ifdef _WIN32

#include <stdio.h>
#include <io.h>
#include <conio.h>

char read_chr(int isTty)
{
	char chr;
	if (isTty)
		return _getch();
	if (scanf_s("%c", &chr, (UINT32)sizeof(char)) && !feof(stdin))
		return chr;
	return 0;
}

char* freerdp_passphrase_read(const char* prompt, char* buf, size_t bufsiz, int from_stdin)
{
	const char CTRLC = 3;
	const char BACKSPACE = '\b';
	const char NEWLINE = '\n';
	const char CARRIAGERETURN = '\r';
	const char SHOW_ASTERISK = TRUE;

	size_t read_cnt = 0, chr;
	char isTty;

	if (from_stdin)
	{
		printf("%s ", prompt);
		fflush(stdout);
		isTty = _isatty(_fileno(stdin));
		while (read_cnt < bufsiz - 1 && (chr = read_chr(isTty)) && chr != NEWLINE &&
		       chr != CARRIAGERETURN)
		{
			if (chr == BACKSPACE)
			{
				if (read_cnt > 0)
				{
					if (SHOW_ASTERISK)
						printf("\b \b");
					read_cnt--;
				}
			}
			else if (chr == CTRLC)
			{
				if (read_cnt != 0)
				{
					while (read_cnt > 0)
					{
						if (SHOW_ASTERISK)
							printf("\b \b");
						read_cnt--;
					}
				}
				else
					goto fail;
			}
			else
			{
				*(buf + read_cnt) = chr;
				read_cnt++;
				if (SHOW_ASTERISK)
					printf("*");
			}
		}
		*(buf + read_cnt) = '\0';
		printf("\n");
		fflush(stdout);
		return buf;
	}
fail:
	errno = ENOSYS;
	return NULL;
}

#elif !defined(ANDROID)

#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#include <sys/stat.h>
#include <termios.h>
#include <unistd.h>
#include <freerdp/utils/signal.h>

char* freerdp_passphrase_read(const char* prompt, char* buf, size_t bufsiz, int from_stdin)
{
	char read_char;
	char* buf_iter;
	char term_name[L_ctermid];
	int term_file, write_file;
	ssize_t nbytes;
	size_t read_bytes = 0;

	if (bufsiz == 0)
	{
		errno = EINVAL;
		return NULL;
	}

	ctermid(term_name);
	if (from_stdin || strcmp(term_name, "") == 0 || (term_file = open(term_name, O_RDWR)) == -1)
	{
		write_file = STDERR_FILENO;
		terminal_fildes = STDIN_FILENO;
	}
	else
	{
		write_file = term_file;
		terminal_fildes = term_file;
	}

	if (tcgetattr(terminal_fildes, &orig_flags) != -1)
	{
		new_flags = orig_flags;
		new_flags.c_lflag &= ~ECHO;
		new_flags.c_lflag |= ECHONL;
		terminal_needs_reset = 1;
		if (tcsetattr(terminal_fildes, TCSAFLUSH, &new_flags) == -1)
			terminal_needs_reset = 0;
	}

	if (write(write_file, prompt, strlen(prompt)) == (ssize_t)-1)
		goto error;

	buf_iter = buf;
	while ((nbytes = read(terminal_fildes, &read_char, sizeof read_char)) == (sizeof read_char))
	{
		if (read_char == '\n')
			break;
		if (read_bytes < (bufsiz - (size_t)1))
		{
			read_bytes++;
			*buf_iter = read_char;
			buf_iter++;
		}
	}
	*buf_iter = '\0';
	buf_iter = NULL;
	read_char = '\0';
	if (nbytes == (ssize_t)-1)
		goto error;

	if (terminal_needs_reset)
	{
		if (tcsetattr(terminal_fildes, TCSAFLUSH, &orig_flags) == -1)
			goto error;
		terminal_needs_reset = 0;
	}

	if (terminal_fildes != STDIN_FILENO)
	{
		if (close(terminal_fildes) == -1)
			goto error;
	}

	return buf;

error:
{
	int saved_errno = errno;
	buf_iter = NULL;
	read_char = '\0';
	if (terminal_needs_reset)
		tcsetattr(terminal_fildes, TCSAFLUSH, &orig_flags);
	if (terminal_fildes != STDIN_FILENO)
		close(terminal_fildes);
	errno = saved_errno;
	return NULL;
}
}

#else

char* freerdp_passphrase_read(const char* prompt, char* buf, size_t bufsiz, int from_stdin)
{
	return NULL;
}

#endif