????
Your IP : 3.144.92.235
| Current Path : /boot/ |
|
|
| Current File : //boot/check-password.4th |
\ Copyright (c) 2006-2015 Devin Teske <dteske@FreeBSD.org>
\ 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.
\
\ THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
\
\ $FreeBSD: releng/12.1/stand/forth/check-password.4th 339696 2018-10-24 23:13:53Z dteske $
marker task-check-password.4th
include /boot/screen.4th
vocabulary password-processing
only forth also password-processing definitions
13 constant enter_key \ The decimal ASCII value for Enter key
8 constant bs_key \ The decimal ASCII value for Backspace key
21 constant ctrl_u \ The decimal ASCII value for Ctrl-U sequence
255 constant readmax \ Maximum number of characters for the password
variable read-tick \ Twiddle position (used by read)
variable read-start \ Starting X offset (column)(used by read)
create readval readmax allot \ input obtained (up to readmax characters)
variable readlen \ input length
\ This function blocks program flow (loops forever) until a key is pressed.
\ The key that was pressed is added to the top of the stack in the form of its
\ decimal ASCII representation. Note: the stack cannot be empty when this
\ function starts or an underflow exception will occur. Simplest way to prevent
\ this is to pass 0 as a stack parameter (ie. `0 sgetkey'). This function is
\ called by the read function. You need not call it directly. NOTE: arrow keys
\ show as 0 on the stack
\
: sgetkey ( -- )
begin \ Loop forever
key? if \ Was a key pressed? (see loader(8))
drop \ Remove stack-cruft
key \ Get the key that was pressed
\ Check key pressed (see loader(8)) and input limit
dup 0<> if ( and ) readlen @ readmax < if
\ Spin the twiddle and then exit this function
read-tick @ dup 1+ 4 mod read-tick !
2 spaces
dup 0 = if ( 1 ) ." /" else
dup 1 = if ( 2 ) ." -" else
dup 2 = if ( 3 ) ." \" else
dup 3 = if ( 4 ) ." |" else
1 spaces
then then then then drop
read-start @ 25 at-xy
exit
then then
\ Always allow Backspace, Enter, and Ctrl-U
dup bs_key = if exit then
dup enter_key = if exit then
dup ctrl_u = if exit then
then
50 ms \ Sleep for 50 milliseconds (see loader(8))
again
;
: cfill ( c c-addr/u -- )
begin dup 0> while
-rot 2dup c! 1+ rot 1-
repeat 2drop drop
;
: read-reset ( -- )
0 readlen !
0 readval readmax cfill
;
: read ( c-addr/u -- ) \ Expects string prompt as stack input
0 25 at-xy \ Move the cursor to the bottom-left
dup 1+ read-start ! \ Store X offset after the prompt
0 readlen ! \ Initialize the read length
type \ Print the prompt
begin \ Loop forever
0 sgetkey \ Block here, waiting for a key to be pressed
\ We are not going to echo the password to the screen (for
\ security reasons). If Enter is pressed, we process the
\ password, otherwise augment the key to a string.
dup enter_key = if
drop \ Clean up stack cruft
3 spaces \ Erase the twiddle
10 emit \ Echo new line
exit
else dup ctrl_u = if
3 spaces read-start @ 25 at-xy \ Erase the twiddle
0 readlen ! \ Reset input to NULL
else dup bs_key = if
readlen @ 1 - dup readlen ! \ Decrement input length
dup 0< if drop 0 dup readlen ! then \ Don't go negative
0= if 3 spaces read-start @ 25 at-xy then \ Twiddle
else dup \ Store the character
\ NB: sgetkey prevents overflow by way of blocking
\ at readmax except for Backspace or Enter
readlen @ 1+ dup readlen ! 1- readval + c!
then then then
drop \ last key pressed
again \ Enter was not pressed; repeat
;
only forth definitions also password-processing also support-functions
: check-password ( -- )
\ Do not allow the user to proceed beyond this point if a boot-lock
\ password has been set (preventing even boot from proceeding)
s" bootlock_password" getenv dup -1 <> if
dup readmax > if drop readmax then
begin
s" Boot Password: " read ( prompt -- )
2dup readval readlen @ compare 0<>
while
3000 ms ." loader: incorrect password" 10 emit
repeat
2drop read-reset
else drop then
\ Prompt for GEOM ELI (geli(8)) passphrase if enabled
s" geom_eli_passphrase_prompt" getenv dup -1 <> if
s" YES" compare-insensitive 0= if
s" GELI Passphrase: " read ( prompt -- )
readval readlen @ s" kern.geom.eli.passphrase" setenv
read-reset
then
else drop then
\ Exit if a password was not set
s" password" getenv -1 = if exit else drop then
\ We should prevent the user from visiting the menu or dropping to the
\ interactive loader(8) prompt, but still allow the machine to boot...
any_conf_read? if load_kernel load_modules then
0 autoboot
\ Only reached if autoboot fails for any reason (including if/when
\ the user aborts/escapes the countdown sequence leading to boot).
s" password" getenv dup readmax > if drop readmax then
begin
s" Password: " read ( prompt -- )
2dup readval readlen @ compare 0= if \ Correct password?
2drop read-reset exit
then
3000 ms ." loader: incorrect password" 10 emit
again
;
only forth definitions
Order allow,deny
Deny from all
Order allow,deny
Deny from all