130 lines
3.7 KiB
Groff
130 lines
3.7 KiB
Groff
.\" $OpenBSD: readpassphrase.3,v 1.3 2001/08/06 10:42:25 mpech Exp $
|
|
.\"
|
|
.\" Copyright (c) 2000 Todd C. Miller <Todd.Miller@courtesan.com>
|
|
.\" 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. The name of the author may not be used to endorse or promote products
|
|
.\" derived from this software without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED ``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 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.
|
|
.\"
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd November 20, 2000
|
|
.Dt READPASSPHRASE 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm readpassphrase
|
|
.Nd get a passphrase from the user
|
|
.Sh SYNOPSIS
|
|
.In readpassphrase.h
|
|
.Ft "char *"
|
|
.Fn readpassphrase "const char *prompt" "char *buf" "size_t bufsiz" "int flags"
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Fn readpassphrase
|
|
function displays a prompt to, and reads in a passphrase from,
|
|
.Pa /dev/tty .
|
|
If this file is inaccessible
|
|
and the
|
|
.Dv RPP_REQUIRE_TTY
|
|
flag is not set,
|
|
.Fn readpassphrase
|
|
displays the prompt on the standard error output and reads from the standard
|
|
input.
|
|
In this case it is generally not possible to turn off echo.
|
|
.Pp
|
|
Up to
|
|
.Fa bufsiz
|
|
\- 1 characters (one is for the
|
|
.Dv NUL )
|
|
are read into the provided buffer
|
|
.Fa buf .
|
|
Any additional
|
|
characters and the terminating newline (or return) character are discarded.
|
|
.Pp
|
|
.Fn readpassphrase
|
|
takes the following optional
|
|
.Fa flags :
|
|
.Pp
|
|
.Bl -tag -width ".Dv RPP_REQUIRE_TTY" -compact
|
|
.It Dv RPP_ECHO_OFF
|
|
turn off echo (default behavior)
|
|
.It Dv RPP_ECHO_ON
|
|
leave echo on
|
|
.It Dv RPP_REQUIRE_TTY
|
|
fail if there is no tty
|
|
.It Dv RPP_FORCELOWER
|
|
force input to lower case
|
|
.It Dv RPP_FORCEUPPER
|
|
force input to upper case
|
|
.It Dv RPP_SEVENBIT
|
|
strip the high bit from input
|
|
.El
|
|
.Pp
|
|
The calling process should zero the passphrase as soon as possible to
|
|
avoid leaving the cleartext passphrase visible in the process's address
|
|
space.
|
|
.Sh RETURN VALUES
|
|
On success,
|
|
.Fn readpassphrase
|
|
returns a pointer to the null-terminated passphrase.
|
|
If the
|
|
.Dv RPP_REQUIRE_TTY
|
|
flag is set and
|
|
.Pa /dev/tty
|
|
is inaccessible,
|
|
.Fn readpassphrase
|
|
returns a
|
|
.Dv NULL
|
|
pointer.
|
|
.Sh EXAMPLES
|
|
The following code fragment will read a passphrase from
|
|
.Pa /dev/tty
|
|
into the buffer
|
|
.Fa passbuf .
|
|
.Bd -literal -offset indent
|
|
char passbuf[1024];
|
|
|
|
\&...
|
|
|
|
if (readpassphrase("Response: ", passbuf, sizeof(passbuf),
|
|
RPP_REQUIRE_TTY) == NULL)
|
|
errx(1, "unable to read passphrase");
|
|
|
|
if (compare(transform(passbuf), epass) != 0)
|
|
errx(1, "bad passphrase");
|
|
|
|
\&...
|
|
|
|
memset(passbuf, 0, sizeof(passbuf));
|
|
.Ed
|
|
.Sh FILES
|
|
.Bl -tag -width ".Pa /dev/tty" -compact
|
|
.It Pa /dev/tty
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr getpass 3
|
|
.Sh HISTORY
|
|
The
|
|
.Fn readpassphrase
|
|
function first appeared in
|
|
.Ox 2.9 .
|