Fortify for Netscape
Farrell McKay
26 Aug 1998
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| Fortify for Netscape | http://www.fortify.net/ Farrell McKay 26 Aug 1998 |
This is Fortify for Netscape, a program that provides world-wide, unconditional, full strength 128-bit cryptography to users of Netscape Navigator (v3) and Communicator (v4).
In the Netscape 2.x and 3.x browsers, Fortify provides full strength, 128-bit encryption facilities. These are used when connecting to an encrypting web server (with the SSL protocol). Without Fortify, the export-grade web browsers are limited to 40-bit encryption facilities, which are substantially weaker, and have been demonstrated to be "crackable".
In the Netscape 4.x browsers, Fortify provides these same 128-bit encryption features, plus the ability to generate 1024-bit RSA keys internally (these are typically used for client certificates), plus the ability to send and receive e-mail messages using strong 128-bit encryption (with the S/MIME protocol).
Further details are provided in the following sections of this document.
When comparing Fortify to alternative strong encryption solutions, such as
SSL relays, SSL proxies, or Java-based applet solutions, a number of
advantages are worth considering:
The recent export releases of Netscape Communicator (version 4 only)
include two high grade SSL ciphers - RC4 128-bit, and triple-DES 168-bit.
However, you must read the fine print. These ciphers are only enabled
when you connect to specific, specially approved SSL web servers (they
are never used to encrypt e-mail messages). If you connect to a
non-approved SSL server, the strongest cipher allowed is 56-bit DES.
Verisign Inc. grants these special approvals, under its Global Server ID
certificate program. Outside the U.S., approvals are only available
to certified banks.
In contrast, Fortify gives you strongly encrypted communications when
you connect to any full strength server, anywhere. No questions asked.
Fortify is available for both Navigator (v3) and Communicator (v4).
Microsoft Internet Explorer also possesses 128-bit cryptography, but it
too is conditional. It is only enabled when connecting to specific,
pre-approved web servers, under a scheme named "Server Gated Cryptography".
In this respect, it is the same as Netscape Communicator. Do not be
misled by statements that suggest anything else.
No version of Fortify for MS-IE is available at this time.
The current release of Fortify supports all of the following
non-beta Netscape browsers (English edition):-
(*) BSD versions v3.01, v3.03-gold, v3.04, and v4.04 onwards only.
Is your platform or operating system missing from this list? Then
now is your chance to cast a vote for your platform. Please take
a few moments to fill in the Fortify
feedback form.
(details below),
and indicate which operating system(s) you use.
Fortify for Netscape is not explicitly regression tested
against any of the international editions of the Netscape browsers.
However, the international and English browsers all use the same
underlying Netscape executable program. Fortify can be expected,
therefore, to successfully recognise and upgrade these browsers.
Indeed, many Fortify users have already reported this to be the case.
Specific beta or preview releases of the Netscape browsers may be
supported from time to time, but, in general, there is no on-going
guarantee that these editions are supported. Being preview releases
they come in fairly low on the priority list, since they typically
have short lifetimes, they are of a poorer quality, and they stretch
resources disproportionately.
If you would like to see a particular preview release supported, feel
free to say so,
and keep an eye out for future announcements (or subscribe to the Fortify
mailing list).
Yes.
Yes. In fact, a fortified browser will always use 128-bit encryption
when connecting to any strongly encrypting web server - regardless
of the server certificate involved. For encryption purposes, the browser
draws no distinction between the various server certificates.
The Fortify home page is on the net, currently at
http://www.fortify.net/
Please refer to that site for download details, and all the latest
news about Fortify.
Before running Fortify, you will need to know the full path name of
your Netscape executable program on your hard disk.
Then, if you are using Windows-95 or Windows-NT, do this:-
Or, if you are using OS/2, do this:-
Or, if you are using Unix, do this:-
Following these steps will cause a precompiled copy of Fortify to
be executed during the upgrade. If you are not happy with the
thought of running a precompiled program that you have downloaded from
the net, then feel free to rebuild it for yourself. The source code
can be found in the 'src' directory. You will need an ANSI-C compiler
such as 'gcc'. Simply edit the src/Makefile file to select your
platform, and then type 'make'. The src/README file contains a few
additional lab notes.
You should flush your Netscape memory and disk caches.
This is not strictly necessary, but it will avoid confusion if you are
in the habit of checking the "Document Information" screen. This screen
reports the SSL secret key length that was used when the document was
fetched from its home web server - which might be earlier than the time
when Fortify was applied if it is a cached document.
You should also check your SSL cipher preferences. If you normally use
a non-default set of SSL ciphers, you may wish to review your choices.
After running Fortify you will have an improved set of ciphers to
choose from. The SSL cipher controls are in the Security Preferences
dialog of the Options menu (v3), or the Security Info window of the
Communicator menu (v4).
Netscape has possessed the ability to perform SSL encryption ever since
the version 2.0 release. The cipher functions have no inherent key length
limitations. However, the export grade browser only generates and uses
40-bit secret keys (padded out with clear text key material where needed).
Fortify simply arranges for Netscape to generate and/or use 128-bit secret
keys whenever possible. It achieves this by installing itself directly
in to the Navigator browser at a small number of specific places. Thus,
no SSL proxy servers or relays are involved. No supplementary libraries
or support programs are installed. No helper applications are needed.
No special certificates are required in either the server or the browser.
You start with a vanilla copy of Netscape. You run Fortify against it.
You finish with a Netscape executable that is equally as strong as the
U.S. domestic version. You then use it in the normal manner. The next
time you connect to any full strength SSL server, 128-bit encryption
will be used, end-to-end, from the server right through to your browser.
No other re-configurations or adjustments are necessary.
In the Netscape 4.x browsers, Fortify also upgrades security in two additional
areas - the maximum RSA key size and the S/MIME e-mail ciphers. The maximum
RSA generated key size is raised from 512 bits (export-grade) to 1024-bits
(domestic-grade). Internally generated RSA keys are typically used for
client certificates, i.e. for authentication purposes.
Strong encryption is provided for your e-mail messages with the presence
of four strong S/MIME encryption ciphers that are not otherwise available
in the export browsers. These ciphers are triple-DES 168-bit, RC2 128-bit,
RC2 64-bit and DES 56-bit. With these ciphers in operation, your e-mail
privacy is substantially enhanced.
Before upgrading your copy of Netscape, Fortify will perform a number of
preliminary checks. It checks that a) it has write permission on your
Netscape program, b) that it can recognize your Netscape program as a known
version (its file size and MD5 fingerprint are used for this), and c) that
the installation for that Netscape version can be applied without error.
If all three tests pass, Fortify then proceeds with the upgrade.
Passing a '-n' parameter to the Fortify script will cause it to run
in 'nowrite' mode. Normal processing occurs, but nothing is actually
installed.
For your added peace of mind, Fortify will offer to retain a backup copy
of your browser in the same directory. The backup file is given a '.sav'
file extension.
At any time you may remove the upgrade from your Netscape browser. You do
this simply by re-running Fortify against your copy of Netscape. Fortify
will detect the upgraded nature of your browser and offer to reverse the
upgrade. Reversing the upgrade returns your browser exactly to its
original form.
Fortify does NOT
Nothing. Fortify will only recognise and upgrade export-grade browsers.
Of course, if you have a U.S.-Domestic browser, you don't need Fortify.
But there is no risk of accidentally damaging your browser through the
use of Fortify.
You have a few alternatives.
The Unix export versions of Netscape describe themselves as
Fortified versions
(and presumably U.S. domestic versions)
describe themselves as
Export versions of Navigator (v3) offer 40-bit RC2 and RC4 ciphers
(example),
whereas the Fortified version offers 128-bit RC4
(example).
Export versions of Communicator (v4) offer 40-bit RC4 for web connections,
or 128-bit RC4 and 168-bit triple-DES when a "blessed" web server is involved
(example).
Fortified versions, however, offer 128-bit RC4 and 168-bit triple-DES
without restriction
(example).
For sending and receiving e-mail, Communicator (v4) offers 40-bit RC2 only
(example),
whereas Fortified versions carry an additional four strong e-mail ciphers
(example).
a) In Navigator v3, the small key icon in the bottom left hand corner
of the browser indicates the encryption status.
b) The "Document Information" screen reports the cipher and key length
that was used when the document was fetched. Strong ciphers are
described as "a high-grade encryption key ....",
while weak ciphers
are described as "a medium-grade encryption key ....".
Alternatively, find an Apache-SSL web server that has the "printenv"
cgi-bin script installed ("printenv" prints all the environment
variables passed to itself; it is included in the vanilla Apache
distribution). Open an SSL connection to this script, e.g.
https://some.server.name/cgi-bin/printenv.
Export versions of Netscape will see a HTML page returned by printenv
that includes these lines:-
Fortified versions (and presumably U.S. domestic versions) will see a
HTML page returned that includes these lines:-
You can also perform the reverse test, i.e. using only high grade
ciphers connect to a server that only accepts export strength SSL
connections. Amazingly, the server at Verisign
(www.verisign.com)
is an example in this category!!
a) build a test bed server that dumps out SSL conversations
(ApacheSSL + SSLeay makes a fine starting point for this),
b) snoop the https packets that pass between the browser and
web server across a network link.
To cut a long story short, there are two types of keys used by Netscape.
One is a "secret key", which encrypts and decrypts your transmitted
data. The secret key is generally between 40 and 168 bits in size,
depending on the cipher involved.
The second key type - the RSA key - actually manifests itself as two
keys, a public and a private key pair. These are used when a new SSL
connection is established to securely exchange secret keys. Public
and private keys are generally at least 512 bits in size.
All this is a gross simplification of SSL key theory. If you want to know
more, you should refer to one of the many fine SSL reference documents
available on the Web.
It is feeble.
Netscape Communications peg the computation effort to exhaustively
search a 40 bit key at approximately 64 MIPS-years (MIPS = millions
of instructions per second). This means that it would take a 1 MIPS
computer 64 years to find a 40 bit key value. A 64 MIPS computer
would take one year to do the same task. Two such computers would
need 6 months of computation. And so on.
Digital Equipment Corporation announced in July 1996 a version of
its 64-bit Alpha 21164 RISC chip that is capable of 2000 MIPS.
Hook together, say, four CPUs of this power, and you have a machine
that can exhaustively search a 40-bit key space in
(64 * 365) / (2000 * 4) = 2.92 days. On average, a key search will
reach its goal in half the maximum search time, i.e. 1.46 days.
This is a crude example. The inescapable conclusion is that large
corporations, governments, and intelligence agencies already have
the ability to break 40-bit keys in real-time. The encryption is
transparent - like using glass windows against a peeping tom.
Similar deficiencies can be seen in the 56-bit DES algorithm.
DES is roughly twenty years old. At the time it was designed and
published it was regarded as being sufficiently strong, given the
computing power that was available in the 1970s. Since then the
algorithm has remained unchanged, and our technology has made
quantum leaps several times over. You can draw your own conclusions...
In a recent article "Minimal Key Lengths for Symmetric Ciphers
to Provide Adequate Commercial Security", several of the world's
leading cryptographers "strongly recommend a minimum key-length
of 90 bits for symmetric cryptosystems (unquote)".
[Ref:
here
].
90-bit keys would appear to be acceptably strong in 1997.
128-bit keys are therefore what the world should be using.
Yes. Several times. One of the first public attacks on a 40-bit
key was carried out in August 1995, as part of Hal's Challenge.
The challenge was ultimately solved independently by two parties.
The first party to find
the key was David Byers and Eric Young,
using approx 50 PCs, 15 workstations and a MasPar MP-1 for the search.
The second
person to find the key was Damien Doliegez (France), who
used approx 20 workstations and two supercomputers for 8 days to
conduct the search.
A group known as the Cypherpunks have banded together to co-operatively
conduct exhaustive key searches in record times using run-of-the-mill
computing resources. Their fastest time for a 40-bit key search
currently stands at 31 hours 47 minutes, which was the time taken
to break
Hal's Second Challenge, also in Aug 1995.
In January and February of 1997, two more cryptography challenges
were broken. The first was a 40-bit cipher key that was broken in a
mere 3.5 hours by Mr. Ian Goldberg at the University of California,
Berkeley, using a network of approx 250 PCs and workstations. The
second was a 48-bit cipher key that was broken in approx 13 days by
a collaborative group of approx 5000 computers operating across the
Internet.
56-bit DES has also been "broken", on at least four separate occasions.
The Deschall group,
headed by Mr. Rocke Verser, announced the winning key to the RSA's first
DES challenge in June 1997.
Deschall was, once again, an Internet-based
collaborative effort. The group used the spare CPU cycles from "tens
of thousands" of standard computers, over a period of roughly four months,
to perform the key search.
The second DES challenge was
completed
in February 1998, by a collaborative group known as distributed.net
in 39 days - one third of the time taken to solve the first DES challenge.
The Electronic Frontier Foundation has accomplished at least two separate
56-bit DES "cracks" in June and July, 1998. The most widely publicized
result
was a solution to the RSA
DES II challenge.
The solution was achieved in 56 hours - substantially faster
than the previous record.
These results once again demonstrate the fact that export grade ciphers,
including DES, are largely ineffective, and their usefulness degrades
rapidly over time.
These and other challenges were published by RSA Inc. on Jan 28th, 1997 as
part of a research exercise into the security of export grade ciphers.
The exercise is on-going
Let's keep the politics to a minimum, ok? Suffice it to say that
privacy is a right, and that the U.S. government's cryptographic export
restrictions are helping no-one (with the possible exception of itself).
If you use a web browser for anything that is even slightly personal,
valuable or sensitive - and sooner or later you will - then you need
strong encryption.
Strong encryption exists right now. It is proven, it is practical,
it is reliable and it is cheap. It is by far the best possible solution
to a worldwide need. Anything less is a sham.
Say "No" to key escrow.
Fortify for Netscape was developed in Australia, using all Australian
resources, with no assistance from Netscape Communications. As such,
it is beyond the ambit of the U.S. Government's export controls.
Australian export regulations do not currently restrict export of
cryptographic software by electronic means, such as FTP or e-mail.
You may have the misfortune of being subject to laws in your home country
that restrict or prohibit the possession of strong cryptography. In such
situations you may find that you cannot legally use Fortify for Netscape
together with a Netscape browser.
Fortify for Netscape is not a Netscape product. Furthermore, the U.S.
export laws prevent Netscape U.S. from providing any official endorsement
or support for Fortify.
You must weigh up this fact against the acceptability of export-grade
cryptography. Support and assistance relating to Fortify for Netscape
is available via the the feedback form on the Fortify web site.
Of course these are not legally authoritative statements. If necessary,
you should obtain proper legal guidance from experts in your home country.
Yes.
The Fortify mailing list is a low volume,
read-only list for people who are interested in
receiving bulletins and announcements regarding the Fortify project.
It is not a discussion forum - mail messages sent to the list
are not redistributed.
You can subscribe to the Fortify mailing list simply by clicking on the
button below.
Or you can use this
more flexible interface
to supply a different subscription email address,
or to unsubscribe from the list.
If you get stuck, you can send an email message to
majordomo@fortify.net
with the single word
help
in the body of the message.
In reply, the list server will automatically send you the instructions for
joining and leaving the mailing list.
If you have a moment, please take the time to
send in
your feedback via the Fortify web site.
At the same time you can subscribe to the Fortify mailing list,
cast your vote for a currently unsupported platform,
or lodge a call for support assistance.
If you wish to send a direct e-mail message, please address it to either
support@fortify.net
(questions or problems related to the installation or use of Fortify),
or
contact@fortify.net
(suggestions, questions, comments, feedback, or more general matters).
Please include the word Fortify somewhere in the
subject line of your message, and ensure that your reply
e-mail address is valid.
What advantages does it have over alternative solutions?
But doesn't Communicator already have 128-bit encryption?
What about Microsoft Internet Explorer? Isn't it 128-bit capable?
What versions of Netscape does it support?
that were released for the following platforms:-
(+) OS/2 version v2.02 (service level 4, 7 or 8) and 4.04b1 only.
Are the international (non-English) editions supported?
Are the beta and preview editions supported?
Is Fortify Year 2000 ready?
Does it work with a server that uses a Verisign Global Server ID?
Installation
Where can I download the most recent version?
I'm impatient. How do I run it?
pkunzip -d -e fn126w32.zip
cd fn126w32
Fortify.exe "C:\Program Files\Netscape\Program\netscape.exe"
fn126w32
folder if you wish. If you think you might wish to uninstall
Fortify some time later, you should retain a copy of the Fortify
distribution archive. This is your choice.
pkunzip -d -e fn127os2.zip
netscape.exe file, say, to n128.exe.
This has become necessary to avoid problems relating to a locked
netscape.exe file when running repack.exe below.
n128.exe file, and then run Fortify:-
cd fn127os2
Repack.exe /EXEPACK:0 C:\Netscape\n128.exe
del C:\Netscape\n128.bak
Fortify.exe C:\Netscape\n128.exe
n128.exe file, and
delete the backup file created by repack.exe
Repack.exe /EXEPACK:2 C:\Netscape\n128.exe
del C:\Netscape\n128.bak
C:\Netscape\n128.exe
rather than
C:\Netscape\netscape.exe
fn127os2
folder if you wish. If you think you might wish to uninstall
Fortify some time later, you should retain a copy of the Fortify
distribution archive. This is your choice.
C:\Netscape\netscape.exe
is shown as an example only.
You should substitute the full path name of the Netscape executable
installed on your machine.
Repack.exe is a utility authored and made publicly available
by IBM employees, and included in the Fortify distribution for your
convenience. LxLite.exe, from your nearest OS/2 FTP server, is a
suitable alternative. These programs can be used to compress and
de-compress most OS/2 Warp programs. Compressing your programs
saves you disk space, at the expense of longer program start-up times.
unix-TYPE:
gzip -dc Fortify-1.2.6-unix-TYPE.tar.gz | tar -xf -
cd Fortify-1.2.6-unix-TYPE
./Fortify.sh [your-Netscape-filename ...]
Fortify-1.2.6-unix-TYPE
folder if you wish. If you think you might wish to uninstall
Fortify some time later, you should retain a copy of the Fortify
distribution archive. This is your choice.
What else do I need to do?
What exactly does Fortify do?
What safeguards does Fortify use? Can I uninstall it?
What does Fortify not do?
What will Fortify do to a U.S.-Domestic grade browser?
Tests and Checks
How do I check the encryption strength of my copy of Netscape?
"This version supports International security ........."
"This version supports U.S. security ..........."
A broken key symbol indicates no encryption
A solid key with a single tooth signifies an export grade cipher (40-bits)
A solid key with two teeth signifies a full strength cipher is in operation.
HTTP_USER_AGENT = Mozilla/3.01 (X11; I; ...platform...)
HTTPS = on
HTTPS_CIPHER = EXP-RC4-MD5
HTTPS_KEYSIZE = 128
HTTPS_SECRETKEYSIZE = 40
HTTP_USER_AGENT = Mozilla/3.01 (X11; U; ...platform...)
HTTPS = on
HTTPS_CIPHER = RC4-MD5
HTTPS_KEYSIZE = 128
HTTPS_SECRETKEYSIZE = 128
Related Issues
What's all this about RSA/RC4/40-bits/512-bits/symmetric keys? I'm confused.
How strong is a 40 bit secret key anyway?
Has anyone ever "broken" one of these keys?
Why should I bother with Fortify? Who cares!
Say "No" to Clipper chips.
Say "No" to key recovery systems.
Say "No" to diluted key lengths.
Say "No" to cryptography that comes with "strings attached".
Is this legal?
Other Resources
Is there a mailing list?
Where do I send feedback or questions?
