f14fb60209
* Updating common/lib * Updating lib/csu * Updating lib/libc * Updating libexec/ld.elf_so * Corrected test on __minix in featuretest to actually follow the meaning of the comment. * Cleaned up _REENTRANT-related defintions. * Disabled -D_REENTRANT for libfetch * Removing some unneeded __NBSD_LIBC defines and tests Change-Id: Ic1394baef74d11b9f86b312f5ff4bbc3cbf72ce2
200 lines
5.3 KiB
Groff
200 lines
5.3 KiB
Groff
.\" $NetBSD: getpass.3,v 1.22 2012/04/14 10:34:29 wiz Exp $
|
|
.\"
|
|
.\" Copyright (c) 1989, 1991, 1993
|
|
.\" The Regents of the University of California. 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. Neither the name of the University nor the names of its contributors
|
|
.\" may be used to endorse or promote products derived from this software
|
|
.\" without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS 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.
|
|
.\"
|
|
.\" @(#)getpass.3 8.1 (Berkeley) 6/4/93
|
|
.\"
|
|
.Dd April 13, 2012
|
|
.Dt GETPASS 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm getpass
|
|
.Nd get a password
|
|
.Sh LIBRARY
|
|
.Lb libc
|
|
.Sh SYNOPSIS
|
|
.In unistd.h
|
|
.Ft char *
|
|
.Fn getpass "const char *prompt"
|
|
.Ft char *
|
|
.Fn getpass_r "const char *prompt" "char *buf" "size_t buflen"
|
|
.Ft char *
|
|
.Fn getpassfd "const char *prompt" "char *buf" "size_t buflen" "int *fd" "int flags" "int timeout"
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Fn getpass
|
|
function displays a prompt to, and reads in a password from,
|
|
.Pa /dev/tty .
|
|
If this file is not accessible,
|
|
.Fn getpass
|
|
displays the prompt on the standard error output and reads from the standard
|
|
input.
|
|
.Pp
|
|
The password may be up to
|
|
.Xr sysconf 3
|
|
.Dv _SC_PASS_MAX
|
|
characters in length.
|
|
Any additional
|
|
characters and the terminating newline character are discarded.
|
|
.Pp
|
|
.Fn getpass
|
|
turns off character echoing while reading the password.
|
|
.Pp
|
|
.Fn getpass_r
|
|
is similar to
|
|
.Fn getpass
|
|
only it puts its result in
|
|
.Fa buf
|
|
for up to
|
|
.Fa buflen
|
|
characters.
|
|
If the
|
|
.Fa buf
|
|
argument is
|
|
.Dv NULL ,
|
|
then a buffer will be dynamically allocated.
|
|
.Pp
|
|
The
|
|
.Fn getpassfd
|
|
function allows one to specify the three file descriptors corresponding to
|
|
.Dv stdin ,
|
|
.Dv stdout ,
|
|
and
|
|
.Dv stderr
|
|
in the
|
|
.Fa fd
|
|
argument, or if
|
|
.Fa fd
|
|
is
|
|
.Dv NULL ,
|
|
.Fn getpassfd
|
|
first attempts to open
|
|
.Pa /dev/tty
|
|
and if that fails, defaults to
|
|
.Dv STDIN_FILENO
|
|
for input and
|
|
.Dv STDERR_FILENO
|
|
for output.
|
|
.Pp
|
|
The behavior of
|
|
.Fn getpassfd
|
|
is controlled by the
|
|
.Fa flags
|
|
argument:
|
|
.Bl -tag -width GETPASS_FORCE_UPPER
|
|
.It Dv GETPASS_NEED_TTY
|
|
Fail if we are unable to set the tty modes like we want.
|
|
.It Dv GETPASS_FAIL_EOF
|
|
Fail if we get the end-of-file character instead of returning the result so far.
|
|
.It Dv GETPASS_BUF_LIMIT
|
|
Beep when the buffer limit is reached, instead of silently absorbing it.
|
|
.It Dv GETPASS_NO_SIGNAL
|
|
Don't make ttychars send signals.
|
|
.It Dv GETPASS_NO_BEEP
|
|
Don't beep if we erase past the beginning of the buffer or we try to enter past
|
|
the end.
|
|
.It Dv GETPASS_ECHO_STAR
|
|
Echo a
|
|
.Sq *
|
|
for each character entered.
|
|
.It Dv GETPASS_ECHO
|
|
Echo characters as they are typed.
|
|
.It Dv GETPASS_ECHO_NL
|
|
Echoes a newline if successful.
|
|
.It Dv GETPASS_7BIT
|
|
Mask the high bit for each entered character.
|
|
.It Dv GETPASS_FORCE_LOWER
|
|
Lowercase each entered character.
|
|
.It Dv GETPASS_FORCE_UPPER
|
|
Uppercase each entered character.
|
|
.El
|
|
.Pp
|
|
Finally if the
|
|
.Fa timeout
|
|
argument is non zero,
|
|
.Fn getpassfd
|
|
will wait for
|
|
.Fa timeout
|
|
seconds for input after each character before returning an error, instead of
|
|
waiting forever.
|
|
.Sh RETURN VALUES
|
|
The
|
|
.Fn getpass
|
|
function returns a pointer to the NUL terminated password, or an empty
|
|
string on error.
|
|
The
|
|
.Fn getpass_r
|
|
and
|
|
.Fn getpassfd
|
|
functions return a pointer to the NUL terminated password, or
|
|
.Dv NULL
|
|
on error.
|
|
.Sh FILES
|
|
.Bl -tag -width /dev/tty -compact
|
|
.It Pa /dev/tty
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr crypt 3
|
|
.Sh STANDARDS
|
|
The
|
|
.Fn getpass
|
|
function appeared in
|
|
.St -susv2 ,
|
|
but it was already marked as legacy.
|
|
The function was removed in the
|
|
.St -p1003.1-2001
|
|
standard.
|
|
.Sh HISTORY
|
|
A
|
|
.Fn getpass
|
|
function appeared in
|
|
.At v7 .
|
|
The
|
|
.Fn getpass_r
|
|
and
|
|
.Fn getpassfd
|
|
functions appeared in
|
|
.Nx 7.0 .
|
|
.Sh BUGS
|
|
The
|
|
.Fn getpass
|
|
function leaves its result in an internal static object and returns
|
|
a pointer to that object.
|
|
Subsequent calls to
|
|
.Fn getpass
|
|
will modify the same object.
|
|
.Sh SECURITY CONSIDERATIONS
|
|
The calling process should zero the password as soon as possible to
|
|
avoid leaving the cleartext password visible in the process's address
|
|
space.
|
|
.Pp
|
|
Historically
|
|
.Nm
|
|
accepted and returned a password if it could not modify the terminal
|
|
settings to turn echo off (or if the input was not a terminal).
|
|
In this implementation, only terminal input is accepted.
|