certutil - decode/encode BASE64/HEX strings.Print symbols by HEX code

所属分类: 脚本专栏 / DOS/BAT 阅读数: 1057
收藏 0 赞 0 分享

1. The thing I used this for wad to decode and encode BASE64 strings. (-decode and -encode command switches) .It has two annoying features here - for decode and encode it needs
-----END CERTIFICATE----- and -----BEGIN CERTIFICATE----- at begining and at the of base64 file.And it prints decoded file in lines with max length of 64 symbols.
So here are two very very very simple scripts that use certutil to decode and encode base64 string (and dealing with begin and end tags) (there are no checks for file existence and if the parameters are correct - I rely on certutil error messages):

decode:

@echo off
setlocal
for /f "delims== tokens=1" %%A in ('type %1') do (
	set encoded=%%A
)
rem two additional lines are needed by certutil
echo -----BEGIN CERTIFICATE-----> %2.tmp
echo %encoded%>>%2.tmp
echo -----END CERTIFICATE----->> %2.tmp


certutil /decode %2.tmp %2
del /S /Q %2.tmp
endlocal

encode:

@echo off
setlocal
certutil /encode %1 %1.encoded
rem create an empty file
break > %2

setlocal ENABLEDELAYEDEXPANSION
(
	for /f "eol=-" %%A in (' type %1.encoded ') do (
		rem this not works - left an empty spaxes after each line from typed file
		rem null< (set /p #=%%A) >>%1.encoded
		
		set result=!result!%%A
	)
)
endlocal & set result=%result%
echo %result%>> %2%
del /S /Q
endlocal

The bad thing is that the base64 strings are stored in a variable and there's a limitations for it's size.But for a small strings it wokrs.

2. Much more interesting.In the help it shows that there's an -decodehex switch.And I was surprised to find that there's also an undocumentes switch -encodehex (strange - decodehex looks more dangerous , because it can be used to produce binaries). Here's an example structure of encoded file:

复制代码 代码如下:

0000 73 65 74 20 78 3d 15 0d  0a 73 65 74 20 79 3d 12   set x=...set y=.
0010 0d 0a 65 63 68 6f 20 2a  2a 25 78 25 25 79 25 2a   ..echo **%x%%y%*
0020 2a    

(just as every hex editor)
This was my attempt to create file that set LF and CR to variables smile - and I still don't know why it was unsuccessful it prints "§↕" (any help here will be welcomed - I don't know what goes wrong).
EDIT: I've set DEC codes instead HEX .Anyway still not works.
In fact the data that is behind the hexes is not necessary - it's only for visualisation .
To decode the sample just use this (if this above is saved in sample.hex) :

certutil -decodehex sample.hex not.working.bat

Any way it works for creation of the famous beep.bat :

0000 65 63 68 6f 20 07
this pattern can be used for creation of bat that echoes a random symbols by hex.Just edit the last character.
and this is a pattern for setting a symbol by hex to %#% variable (just edit the last character):
0000 73 65 74 20 78 3d 15 0d
Anyway there are few more things that I want to try with this smile

here's a how forfiles can be used for hex symbols

更多精彩内容其他人还在看

for 语句从入门到精通

在批处理中,for是最为强大的命令语句,它的出现,使得解析文本内容、遍历文件路径、数值递增/递减等操作成为可能
收藏 0 赞 0 分享

dos 目录跳转 cd

当我们需要处理不同路径下的文件的时候,很可能需要切换目录,这个时候,可以考虑使用目录跳转命令cd。
收藏 0 赞 0 分享

tree 以树形格式罗列文件

tree ,在英语中的基本含义是“树”,在cmd中,tree命令的功能是以树形格式罗列文件。
收藏 0 赞 0 分享

dos 内容重定向

当我们在cmd窗口中查询某条命令的帮助信息的时候,帮助信息是显示在命令行窗口中的,命令行窗口关闭后,这些帮助信息就看不到了,如果下次还想看,又得在命令行窗口中输入查询命令,比较繁琐。
收藏 0 赞 0 分享

执行批处理bat程序中的条件处理

一直用bat实现部分功能,对于我们仍需要控制是否满意我们的要求,下面是if帮助文档,方便查询
收藏 0 赞 0 分享

不错的批处理脚本 第一部分

非常不错的批处理脚本代码,功能比较多,用到了,很多的批处理机器
收藏 0 赞 0 分享

不错的批处理脚本实例代码 第二部分

不错的批处脚本实例代码,用到了批处理中的很多技巧与知识点,不懂得可以逐一查找相关资料
收藏 0 赞 0 分享

开机更新桌面主题的批处理代码

更新桌面主题的批处理代码
收藏 0 赞 0 分享

非常好的for 教程, 当时我就是看这个学习for 的第1/2页

批处理for命令详解 FOR这条命令基本上都被用来处理文本,但还有其他一些好用的功能! 看看他的基本格式(这里我引用的是批处理中的格式,直接在命令行只需要一个%号)
收藏 0 赞 0 分享

批处理的"循环"效果脚本

曾经在回答一个问题时 无意中想到的方法 今天又看到类似的问题 个人认为是非常实用的 于是 想把这种方法推荐给大家
收藏 0 赞 0 分享
查看更多