Password Input (new method)

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carlos
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Password Input (new method)

#1 Post by carlos » 01 Apr 2015 14:24

Hello. Time ago a method for get a password input, showing the * was developed using xcopy.exe. But today, I write a new method, using replace.exe.
The code is very readable, support almost all characters, including the !

Example:
C:\dev>password_input.cmd
Enter a Password:******
Your input was:carlos


password_input.cmd

Code: Select all

@Echo Off
SetLocal EnableExtensions EnableDelayedExpansion

Set /P "=Enter a Password:" < Nul
Call :PasswordInput
Echo(Your password text:!pwd!
Pause

Goto :Eof

:PasswordInput
:: consolesoft.com/batch/?#password_input
::Author: Carlos Montiers Aguilera
::Last updated: 20150405. Created: 20150401.
::Set variable pwd with input password
::Needs delayed expansion enabled
Set "pwd="
Set "INTRO=" &For /F "skip=1" %%# in (
'"Echo(|Replace.exe ? . /U /W"'
) Do If Not Defined INTRO Set "INTRO=%%#"
For /F %%# In (
'"Prompt $H &For %%_ In (_) Do Rem"') Do Set "BKSPACE=%%#"
:_PasswordInput_Kbd
Set "Excl="
Set "CHR=" &For /F skip^=1^ delims^=^ eol^= %%# in (
'Replace.exe ? . /U /W') Do If Not Defined CHR (
Set "CHR=%%#" &If "%%#"=="!" Set "Excl=yes")
If "!INTRO!"=="!CHR!" Echo(&Goto :Eof
If "!BKSPACE!"=="!CHR!" (If Defined pwd (
Set "pwd=!pwd:~0,-1!"
Set /P "=!BKSPACE! !BKSPACE!" <Nul)
Goto :_PasswordInput_Kbd
) Else If Not Defined Excl (
Set "pwd=!pwd!!CHR:~0,1!"
) Else Set "pwd=!pwd!^!"
Set /P "=*" <Nul
Goto :_PasswordInput_Kbd

Last edited by carlos on 04 Apr 2015 21:18, edited 11 times in total.

npocmaka_
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Re: Password Input (new method)

#2 Post by npocmaka_ » 01 Apr 2015 15:28

I have an endless "*Path not found - CONIN$"

:|

carlos
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Re: Password Input (new method)

#3 Post by carlos » 01 Apr 2015 15:36

npocmaka, thanks for report it. I'm updated for not use it. Please test again.

npocmaka_
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Re: Password Input (new method)

#4 Post by npocmaka_ » 01 Apr 2015 15:42

Great!
Now its working and I cant broke it with special characters :)

carlos
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Re: Password Input (new method)

#5 Post by carlos » 04 Apr 2015 14:00

Thanks, I've updated the code improving the readability and also fixing a problem if you press Ctrl+Z.

aGerman
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Re: Password Input (new method)

#6 Post by aGerman » 04 Apr 2015 14:31

Carlos

your script works great except if there are parentheses or ampersands in the batch file name.
Those will break your first replace.exe call. Rather escape the pipe character instead of enclosing the command line into quotation marks.

Code: Select all

'Echo(^|Replace.exe "%~f0" . /U /W') Do Set "INTRO=%%#"

Regards
aGerman

carlos
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Re: Password Input (new method)

#7 Post by carlos » 04 Apr 2015 15:27

Thanks aGerman for the info.
For avoid problems with filenames with special characters I replace %~f0 with a wildcard. It works.
Seems that replace.exe accept wildcards for found a file (undocumented?).
Also, previously I use the full path of the script file (%~f0), replacing in the current directory (.). Because it if the current directory inside the script would different that the path of the script it will copy the current script if a file with the same name and old date exist in the current directory.
Now, I specify a file of the current directory using the wildcard ?, because it, both are in the current directory, have the same date, never a replace operation would happen.

Script updated !!!

aGerman
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Re: Password Input (new method)

#8 Post by aGerman » 04 Apr 2015 15:38

Because it if the current directory inside the script would different that the path of the script it will copy the current script if a file with the same name and old date exist in the current directory.

I already tried to change the working directory but that didn't ever happen. You could have fixed that by using "%~dp0." Nevermind. The wildcard workaround seems to work well.

Regards
aGerman

EDIT: Now I see your point. The script has to exist in both directories then ...

carlos
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Re: Password Input (new method)

#9 Post by carlos » 04 Apr 2015 16:00

aGerman, also I tested and updated again for work on windows xp.
On windows xp replace.exe, unlike windows 8, if none replace happen it print at end a text saying it.

windows xp spanish pressing a:

Code: Select all

C:\DEV>replace.exe ? . /U /W
Presione cualquier tecla para continuar . . .
a
No se ha reemplazado ningún archivo



Script updated again for works on windows xp.
Edit:Updated again fixing a problem with the ! on windows xp

aGerman
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Re: Password Input (new method)

#10 Post by aGerman » 04 Apr 2015 17:24

Carlos

May you run that version against XP please:

Code: Select all

@echo off &setlocal

<nul set /p "=Enter your password: "
call :HInput pw
echo Input length is %errorlevel%
setlocal EnableDelayedExpansion
echo Your password is !pw!
pause
goto :eof


:HInput [ByRef_VarName]
:: inspired by Carlos
if "%__HI__%" neq "__HI__" (
  setlocal DisableDelayedExpansion EnableExtensions
  set "CR=" &set "S=" &set "N=0" &set "__HI__=__HI__"
  for /f "skip=1" %%i in ('echo(^|replace ? . /u /w') do if not defined CR set "CR=%%i"
  for /f %%i in ('"prompt $H &for %%b in (1) do rem"') do set "BS=%%i"
)
set "C="
for /f skip^=1^ delims^=^ eol^= %%i in ('replace ? . /u /w') do if not defined C set "C=%%i"
setlocal EnableDelayedExpansion EnableExtensions
if "!CR!"=="!C!" (
  echo(
  if "%~1"=="" (
    echo(!S!
    endlocal &endlocal &exit /b %N%
  ) else (
    if defined S (
      for /f delims^=^ eol^= %%i in ("!S!") do endlocal &endlocal &set "%~1=%%i" &exit /b %N%
    ) else endlocal &endlocal &set "%~1=" &exit /b 0
  )
)
if "!BS!"=="!C!" (
  set "C="
  if defined S set /a "N -= 1" &set "S=!S:~,-1!" &<nul set /p "=%BS% %BS%"
) else set /a "N += 1" &<nul set /p "=*"
if not defined S (
  endlocal &set "N=%N%" &set "S=%C%"
) else for /f delims^=^ eol^= %%i in ("!S!") do endlocal &set "N=%N%" &set "S=%%i%C%"
goto HInput

Regards
aGerman

EDIT slighty changed ...
Carlos' further improvements implemented.

Explanation of used symbols:
:HInput is for "hidden input"
CR carriage return character
BS backspace character
C entered character
S string of entered characters
N number of entered characters in S
__HI__ helper variable (instead of having a helper label) to skip the initialization of variables

carlos
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Re: Password Input (new method)

#11 Post by carlos » 04 Apr 2015 17:55

aGerman, your code works ok on xp.
I only will add to it the enableextensions because exit /b works with it.
Also, in my last update, I only used "skip=1" for set the CR variable.

aGerman
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Re: Password Input (new method)

#12 Post by aGerman » 04 Apr 2015 18:12

Thanks Carlos, did the changes.

By the way feel free to adopt my version in whatever kind. It's basically nothing but your idea. I just added the character counting and tried to make it a little more readable by line indentations.

Regards
aGerman

carlos
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Re: Password Input (new method)

#13 Post by carlos » 04 Apr 2015 21:21

thanks aGerman, I only renamed the variable line to pwd, is short like pw in your script.

aGerman
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Re: Password Input (new method)

#14 Post by aGerman » 05 Apr 2015 08:29

Well perhaps my variable names are too short to be self-explanatory.
For those who are interested in I appended the explantion.

Regards
aGerman

Squashman
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Re: Password Input (new method)

#15 Post by Squashman » 22 Oct 2015 10:42

carlos wrote:Hello. Time ago a method for get a password input, showing the * was developed using xcopy.exe.

I can't find that thread. I thought I remember commenting in that thread but can't find it.

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