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[liberationtech] PGP is hard to use and needs stuff installed on your computer. Use PassLok instead.

Francisco Ruiz ruiz at
Sat Jul 27 12:58:20 PDT 2013

Thanks for your excellent feedback, David,

PassLok 1.2 is a perfectly static page. Therefore, I don't believe it is
vulnerable to the standard XSS attack, as CERT says:

"A web page contains both text and HTML markup that is generated by the
server and interpreted by the client browser. Web sites that generate only
static pages are able to have full control over how the browser interprets
these pages. Web sites that generate dynamic pages do not have complete
control over how their outputs are interpreted by the client. The heart of
the issue is that if mistrusted content can be introduced into a dynamic
page, neither the web site nor the client has enough information to
recognize that this has happened and take protective actions." (CERT
Coordination Center).

Now, I am worried about an attacker replacing the original page with
another page with broken or backdoor encryption. This is why requests to
download PassLok are redirected to https. I've tried to hide the identity
of the server as best as I could but there is still the possibility that
someone might find the server, hack it somehow, and change the code, even
replacing the self-check string in the help file.

I think the best defense against this is mirroring, so an attacker would
have to hack multiple unrelated servers to get away with it. It would be
great if people could provide some mirrors. I would list them all in the
help page (or even the index page, if they are not too many), and let the
user download several and do a file comparison.

Again, any ideas in this respect will be greatly appreciated.


On Fri, Jul 26, 2013 at 3:59 PM, <ddahl at> wrote:

> You should use ContentSecurityPolicy to help avoid XSS attacks:
> Regards,
> David
> On Fri, 26 Jul 2013 15:42:02 -0500, Francisco Ruiz <ruiz at> wrote:
> > Scenario: you, Alice, realize you're under NSA surveillance. You need to
> > get a crucial bit of information to your friend Bob, right away.
> > You've been using PGP, but now you suspect the NSA may have installed a
> bug
> > on your machine. Your keystrokes are being recorded.
> >
> > What can you do? Use PassLok instead.
> >
> > I wrote PassLok with three guiding principles in mind:
> > 1. Absolutely nothing should be installed or even written in the
> computer.
> > Alice should be able to go to the local library or borrow someone else's
> > smartphone, and leave no traces behind.
> > 2. Best security available. No compromises.
> > 3. Graphical interface. Only one screen, as clean as possible.
> >
> > Therefore, PassLok is written entirely in javascript. Once you load the
> > page at ( redirects you
> > there), you can save the file and you have PassLok even offline. You can
> > view the source and convince yourself that it is not connecting with any
> > server. If you know some cryptography, you can see that it is using the
> > well-known SJCL routines for AES encryption/decryption and elliptic curve
> > functions. Since the elliptic curves implemented in the current version
> of
> > SJCL only go up to the 384-bit NIST curve, I added the 521-bit NIST curve
> > (equivalent to a 15000-bit RSA key in predicted security) so that PassLok
> > uses that as a default. Even at 521 bits, the public keys are small, as
> you
> > can see from my lock (public key) below.
> >
> > PassLok performs public-key cryptography using the Diffie-Hellman key
> > exchange rather than RSA, so you can use whatever secret key you want.
> > Hopefully something that is both very hard to guess and easy to remember,
> > so you never have to write it down. PassLok will help you to come up
> with a
> > strong key, but won't force you in any way.
> >
> > PassLok can sign and verify signatures, too (many PGP implementations,
> such
> > as Mailvelope, cannot), and can also include a second secret message
> under
> > a separate key, to beat the "rubberhose attack." If you are not sure
> about
> > the authenticity of something, PassLock can make a short ID that you can
> > read over the phone. All of it from a single screen.
> >
> > I want people to use PassLok and uncover any bugs it might still have,
> > before I move on to a Gmail plugin based on its engine. I believe it is
> > already very secure and easy to use by those who know a little
> > cryptography. Hopefully the metaphor used throughout PassLok, about locks
> > and keys rather than private/public key pairs, will also make it usable
> by
> > novices.
> >
> > I'll appreciate any feedback you can give me. The link is repeated at the
> > bottom.
> >
> > Thanks!
> >
> > --
> > Francisco Ruiz
> > Associate Professor
> > MMAE department
> > Illinois Institute of Technology
> >
> > my PassLok lock:
> >
> >
> PL12lok=KpYv+bqJ7pq0eqC664UlIcwfl1P8f8p12NUqFdg2bQ2gTQTBuOo09BQs3GGiYOQUuQmtnoceAxJoSzjvYEYOM0q=PL12lok
> >
> > get the PassLok privacy app at:
> > --
> > Too many emails? Unsubscribe, change to digest, or change password by
> emailing moderator at companys at or changing your settings at
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