Linux
Folder Structure
- /bin - These are the programs that make
Linux run (ie., binaries in LInux)
- /etc - configuration files are stored(usually
txt format )
- /dev - similar to Windows device drivers.
- /var - log files, among other files, are
stored.
Note:
·
Linux is Case-
Sensitive
·
Linux allows us to modify its commands by using switches
·
switches are
usually letters preceded by the dash
(-)
·
With most commands, you can also use either the -h switch or the --help switch after the command
to obtain "help".
·
Binaries are the files that are the
equivalent of executables in Windows.
·
Binaries are files that do something
like echo, ls, cd, mv, etc.
·
Probably the most important variable in our environment is our PATH variable
Summary:
1. Network : whoami, ifconfig, dig, find
2. Editing :
touch, cat, more ,less ,Nano,grep ,head ,tail ,sed ,nl
3. File and Folders : Pwd ,cd ,ls, mkdir ,cp ,mv(move /rename),
which, whereis ,locate ,unzip, , tar xvf, chmod , nzip
4. System :
apt-get install, gcc , ps ,PID, ./,top ,set, export, uname-a, lsmod ,modproble
–v/-r/-l
5. Misc: man, echo, PS1,clear
Commands
present
working directory> pwd
move me up one
level> cd ..
name of the
user we're logged in> whoami
Change
Directory (Cd)> cd /newfolder
Listing
Command (Ls)
> ls
> ls –la
-a switch
means all
-l switch, it
gives us info on the security permissions, the size, etc.,
Result: drwxr—r-x ……
d-
directory
read/write/execute
=owner
only read =group
read/execute =others
Create a
File (Touch)> touch newfile
Create a
Directory (Mkdir) > mkdir
newdirectory
Getting
Help (Man) > man touch
Copying
Files (Cp) > cp /etc/newfile /root
Moving
Files (Mv) > mv /root/newfile /
Viewing
Files (Cat, More, Less,Nano)
> cat
README
> more
README
> less
README
> Nano README
To view beginning of the file
>head
/etc/snort/snort.conf
>head -30
/etc/snort/snort.conf
To view last lines of the
file>tail /etc/snort/snort.conf
Numbering Those Lines>nl
snort.conf
I Grep That
Only
display lines with “database” in snort.conf file
>cat
/etc/snort/ snort.conf | grep database
I Sed That Works
Replace
every occurrence of mysql > MySQL
>sed
s/mysql/MySQL/g snort.conf > snort2.conf
If I want to only replace the third
occurrence of the word mysql and save as snort2.conf
sed
s/mysql/MySQL/3 snort.conf > snort2.conf
Networking
(Ifconfig)>ifconfig
Changing
IP Addresses>ifconfig eth0 192.168.1.115 netmask 255.255.255.0 broadcast
192.168.1.255
DNS
(Domain Name Service)
Translates to the appropriate IP
address.
Linux users will often refer to DNS
as BIND,
>dig wonderhowto.com ns
WonderHowTo's email servers.
>dig wonderhowto.com mx
Add or remove new server in
the file below:
/etc/resolv.conf
Finding
Files in a Directory (Find)
> find
-name aircarck-ng
> find
/pentest -name aircrack-ng
PATH
variable contains path to bin directory
> echo $PATH
> which ls
Finding
Any File in Any Directory (Whereis)> whereis aircrack-ng
Finding
Files Using the Database (Locate)>locate
aircrack-ng
Unzip>unzip DVWA-1.0.8.zip -d /var/www
Command
Line Package Management or Installer>apt-get
install aircrack-ng
Untar>tar xvf aircrack-ng-1.2-beta1.tar
Complie>gcc aircrack-ng
Install>./aircrack-ng
Changing permissions
(read ,write,edit -> owner,group,user)
Rwx=4 2 1=7
rwxrwxrwx =>Chmod 777 readme= Chmod owner, group, user
rw- r- - r- - =Chmod644 = Chmod
Owner read write rest is read only
Running
Process
>ps aux
>PID 5143
>ps –A
top
processes>top
Killing Processes
>kill 5143
>kill -9 = No
prisoners
View Our
Environment Variables
>set HISTSIZE=123
>echo $HISTSIZE
Adding
application to path>PATH=$PATH:/pentest/wireless/aircrack-ng
Changing
Our Terminal Prompt
>PS1= "World's Best Hacker: #"
>export
PS1
Start
Apache Daemon
Goto Applications -> Services
-> HTTPD and click on apache start.
Apache's
default webpage is /var/www/index.html.
User can edit this to displayed
whatever he wants
Damn
Vulnerable Web Application (DVWA)
> nzip DVWA-1.0.8.zip -d
/var/www
> chmod 755 DVWA-1.0.8
Checking the Kernel
>; –a
or
>cat /proc/version
To tune
kernel options>less /etc/sysctl.conf
List all
drivers (Add a Module ie., driver)
> lsmod (
Or
> modprobe –l
Add
a Module(driver)
> modprobe
foo
Finding info about a module
> modinfo
-v {module-name-here}
Remove
a module (Driver)> modprobe
-r foo
