*> Title:   Tutorial on hacking through a UNIX system


** 
 
In the following file, all references 
made to the name Unix, may also be 
substituted to the Xenix operating 
system. 
 
Brief history:  Back in the early 
sixties, during the development of 
third generation computers at MIT, 
a group of programmers studying the 
potential of computers, discovered 
their ability of performing two or 
more tasks simultaneously.  Bell 
Labs, taking notice of this discovery, 
provided funds for their developmental 
scientists to investigate into this 
new frontier.  After about 2 years of 
developmental research, they produced 
an operating system they called "Unix". 
 
Sixties to Current:  During this time 
Bell Systems installed the Unix system 
to provide their computer operators 
with the ability to multitask so that 
they could become more productive, 
and efficient.  One of the systems they
put on the Unix system was called 
"Elmos". Through Elmos many tasks (i.e.
billing,and installation records) could 
be done by many people using the same 
mainframe. 
 
Note: Cosmos is accessed through the 
Elmos system. 
 
Current:  Today, with the development 
of micro computers, such multitasking 
can be achieved by a scaled down 
version of Unix (but just as 
powerful).  Microsoft,seeing this 
development, opted to develop their own 
Unix like system for the IBM line of 
PC/XT's.  Their result they called 
Xenix (pronounced zee-nicks).  Both 
Unix and Xenix can be easily installed 
on IBM PC's and offer the same function 
(just 2 different vendors). 
 
Note: Due to the many different 
versions of Unix (Berkley Unix, 
Bell System III, and System V 
the most popular) many commands 
following may/may not work. I have 
written them in System V routines. 
Unix/Xenix operating systems will 
be considered identical systems below. 
 
How to tell if/if not you are on a 
Unix system:  Unix systems are quite 
common systems across the country. 
Their security appears as such: 
 
Login;     (or login;) 
password: 
 
When hacking on a Unix system it is 
best to use lowercase because the Unix 
system commands are all done in lower- 
case. 
Login; is a 1-8 character field. It is 
usually the name (i.e. joe or fred) 
of the user, or initials (i.e. j.jones 
or f.wilson).  Hints for login names 
can be found trashing the location of 
the dial-up (use your CN/A to find 
where the computer is). 
Password: is a 1-8 character password 
assigned by the sysop or chosen by the 
user. 
      Common default logins 
   -------------------------- 
   login;       Password: 
   root         root,system,etc.. 
   sys          sys,system 
   daemon       daemon 
   uucp         uucp 
   tty          tty 
   test         test 
   unix         unix 
   bin          bin 
   adm          adm 
   who          who 
   learn        learn 
   uuhost       uuhost 
   nuucp        nuucp 
 
If you guess a login name and you are 
not asked for a password, and have 
accessed to the system, then you have 
what is known as a non-gifted account. 
If you guess a correct login and pass- 
word, then you have a user account. 
And, if you get the root p/w you have
a "super-user" account. 
All Unix systems have the following 
installed to their system: 
root, sys, bin, daemon, uucp, adm 
Once you are in the system, you will 
get a prompt. Common prompts are: 
 
$ 
% 
# 
 
But can be just about anything the 
sysop or user wants it to be. 
 
Things to do when you are in: Some 
of the commands that you may want to 
try follow below: 
 
who is on  (shows who is currently 
            logged on the system.) 
write name (name is the person you 
            wish to chat with) 
      To exit chat mode try ctrl-D. 
      EOT=End of Transfer. 
ls -a      (list all files in current 
            directory.) 
du -a      (checks amount of memory 
            your files use;disk usage) 
cd\name    (name is the name of the 
            sub-directory you choose) 
cd\        (brings your home directory 
            to current use) 
cat name   (name is a filename either 
            a program or documentation 
            your username has written) 
      Most Unix programs are written 
      in the C language or Pascal 
      since Unix is a programmers' 
      environment. 
One of the first things done on the 
system is print up or capture (in a 
buffer) the file containing all user 
names and accounts. This can be done 
by doing the following command: 
 
cat /etc/passwd 
 
If you are successful you will see a list
of all accounts on the system.  It 
should look like this: 
 
root:hvnsdcf:0:0:root dir:/: 
joe:majdnfd:1:1:Joe Cool:/bin:/bin/joe 
hal::1:2:Hal Smith:/bin:/bin/hal 
 
Te "root" line tells the following 
info : 
login name=root 
hvnsdcf   = encrypted password 
0         = user group number 
0         = user number 
root dir  = name of user 
/         = root directory 
 
In the Joe login, the last part 
"/bin/joe " tells us which directory 
is his home directory (joe) is. 
 
In the "hal" example the login name is 
followed by 2 colons, that means that 
there is no password needed to get in 
using his name. 
 
Conclusion:  I hope that this file 
will help other novice Unix hackers 
obtain access to the Unix/Xenix 
systems that they may find.