/**
* @file
*
* @brief Shell login prompt functions.
*/
/*
* Authorship
* ----------
* Parts of this software was created by
* Till Straumann <strauman@slac.stanford.edu>, 2003-2007
* Stanford Linear Accelerator Center, Stanford University.
*
* Acknowledgement of sponsorship
* ------------------------------
* Parts of this software was produced by
* the Stanford Linear Accelerator Center, Stanford University,
* under Contract DE-AC03-76SFO0515 with the Department of Energy.
*
* Government disclaimer of liability
* ----------------------------------
* Neither the United States nor the United States Department of Energy,
* nor any of their employees, makes any warranty, express or implied, or
* assumes any legal liability or responsibility for the accuracy,
* completeness, or usefulness of any data, apparatus, product, or process
* disclosed, or represents that its use would not infringe privately owned
* rights.
*
* Stanford disclaimer of liability
* --------------------------------
* Stanford University makes no representations or warranties, express or
* implied, nor assumes any liability for the use of this software.
*
* Stanford disclaimer of copyright
* --------------------------------
* Stanford University, owner of the copyright, hereby disclaims its
* copyright and all other rights in this software. Hence, anyone may
* freely use it for any purpose without restriction.
*
* Maintenance of notices
* ----------------------
* In the interest of clarity regarding the origin and status of this
* SLAC software, this and all the preceding Stanford University notices
* are to remain affixed to any copy or derivative of this software made
* or distributed by the recipient and are to be affixed to any copy of
* software made or distributed by the recipient that contains a copy or
* derivative of this software.
*
* ------------------ SLAC Software Notices, Set 4 OTT.002a, 2004 FEB 03
*
* Copyright (c) 2009 embedded brains GmbH and others.
*
* embedded brains GmbH
* Obere Lagerstr. 30
* D-82178 Puchheim
* Germany
* <rtems@embedded-brains.de>
*
* Based on work from Chris Johns, Fernando Ruiz and Till Straumann.
*
* Derived from files "cpukit/libmisc/shell/shell.c" and
* "cpukit/telnetd/check_passwd.c".
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.com/license/LICENSE.
*/
#include <stdio.h>
#include <termios.h>
#include <unistd.h>
#include <ctype.h>
#include <rtems/shell.h>
static int rtems_shell_discard( int c, FILE *stream)
{
return c;
}
static void rtems_shell_get_text(
FILE *in,
FILE *out,
char *line,
size_t size
)
{
int fd_in = fileno( in);
int (*put)( int, FILE *) =
out != NULL && isatty( fd_in)
? fputc
: rtems_shell_discard;
size_t i = 0;
if (size < 1) {
return;
}
tcdrain( fd_in);
if (out != NULL){
tcdrain( fileno( out));
}
while (true) {
int c = fgetc( in);
switch (c) {
case EOF:
/* Here comes an ugly hack: The Termios driver's read() handler returns
* 0 to the C library's fgets() if it times out. fgets() interprets
* this (correctly) as EOF, a condition we want to undo since it's not
* really true since we really have a read error (Termios bug?).
*
* As a workaround we push something back and read it again. This
* should simply reset the EOF condition.
*/
if (ungetc( '?', in) == '?') {
fgetc( in);
}
break;
case '\n':
case '\r':
put( '\n', out);
line [i] = '\0';
return;
case 127:
case '\b':
if (i > 0) {
put( '\b', out);
put( ' ', out);
put( '\b', out);
--i;
} else {
put( '\a', out);
}
break;
default:
if (!iscntrl( c)) {
if (i < size - 1) {
line [i] = (char) c;
++i;
put( c, out);
} else {
put( '\a', out);
}
} else {
put( '\a', out);
}
break;
}
}
}
bool rtems_shell_login_prompt(
FILE *in,
FILE *out,
const char *device,
rtems_shell_login_check_t check
)
{
int fd_in = fileno( in);
struct termios termios_previous;
bool restore_termios = false;
int i = 0;
bool result = false;
if (tcgetattr( fd_in, &termios_previous) == 0) {
struct termios termios_new = termios_previous;
termios_new.c_lflag &= (unsigned char) ~ECHO;
termios_new.c_lflag &= (unsigned char) ~ICANON;
termios_new.c_cc [VTIME] = 255;
termios_new.c_cc [VMIN] = 0;
restore_termios = tcsetattr( fd_in, TCSANOW, &termios_new) == 0;
}
for (i = 0; i < 3; ++i) {
char user [32];
char passphrase [128];
fprintf( out, "%s login: ", device);
fflush( out);
rtems_shell_get_text( in, out, user, sizeof( user));
fflush( in);
fprintf( out, "Password: ");
fflush( out);
rtems_shell_get_text( in, NULL, passphrase, sizeof( passphrase));
fputc( '\n', out);
result = check( user, passphrase);
if (result) {
break;
}
fprintf( out, "Login incorrect\n\n");
sleep( 2);
}
if (restore_termios) {
/* What to do if restoring the flags fails? */
tcsetattr( fd_in, TCSANOW, &termios_previous);
}
return result;
}
