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PGP & GPG
Posted by
samzenpus
on Mon Jun 26, 2006 03:07 PM
from the lock-it-up dept.
from the lock-it-up dept.
Ben Rothke writes "PGP (Pretty Good Privacy), as most Slashdot readers know, is one of the most popular software encryption programs ever. It is so good and so effective that in the early 1990s the FBI launched a multi-year investigation against Phil Zimmerman, the creator of PGP, for possible violation of federal export laws, especially ITAR (International Traffic in Arms Regulation). After many years of investigation, the FBI ultimately dropped its case against Zimmerman. Even though PGP is synonymous with end-user encryption, there have only been a few books written on the subject. Jump to 2006, and PGP & GPG: Email for the Practical Paranoid is a welcome title." Read the rest of Ben's review.
On page 167 in Appendix A of the book, the author candidly writes that PGP "comes with a very good and complete manual at over 300 pages". With that, one may question why one would spend $24.95 on a book which covers much of the same information as the bundled documentation.
The reality is that there is a large class of people that will simply not read any form of documentation. Rather, they prefer something with an ISBN number. Such people are a boon to authors (of which I am one) and publishers. For that group, PGP & GPG: Email for the Practical Paranoid provides a pretty good overview of how to use PGP.
The book is written for an end-user who, while comfortable with the workings of technology, is new to the sometimes strange world of public key cryptography. The author writes in an easy-to-read style and, through repetition, inculcates the principal ideas of encryption and cryptography to the reader.
The introduction and first chapter provide a good presentation of the concepts of encryption, cryptography and public-key cryptography. The idea of public-key cryptography, on which PGP is based, is not so intuitive, and many people struggle with the basic concepts. The first chapter, appropriately titled 'Cryptography Kindergarten' is a good read for those who are public-key cryptography challenged.
On a side note, the notion that even smart end-users can be intimidated by public key cryptography was detailed in a now seminal research paper 'Why Johnny Can't Encrypt: A Usability Evaluation of PGP 5.0.'
The premise of the paper is that user errors cause or contribute to most computer security failures, yet user interfaces for security still tend to be clumsy, confusing, or near-nonexistent. The authors argue that effective security requires a different usability standard, and that it will not be achieved through the user interface design techniques appropriate to other types of consumer software. The authors conclude that PGP 5.0 is not usable enough to provide effective security for most computer users despite its attractive graphical user interface. Even though PGP is in version 9.x, it still suffers from usability flaws.
Cryptography purists may recoil when the author repeatedly uses the term 'military-grade encryption.' Military-grade encryption and military-grade cryptography are overused terms, most often by marketing departments, but there is no real definition of 'military-grade encryption' -- and even if there were, it would be classified. Most people use 'military-grade encryption' to mean really strong crypto, much like those who use the term 'Olympic-size swimming pool' to refer to a really large pool. But the term 'military-grade encryption' is so misused by so many people that it is a lost cause to try to fight it.
In the rest of the book, chapters 2 - 11, the author details the varied usages of PGP & GPG. The book also details the differences between OpenPGP, PGP and GPG.
The difference between them is that PGP is a commercial piece of software, GPG (Gnu Privacy Guard) is open source, and OpenPGP is a protocol that defines a standard format for encrypted messages, signatures, and certificates for exchanging public keys.
The author astutely writes that while PGP provides really strong security, this is only if, and this is a huge if, it is implemented correctly. Chapter 11 notes that although OpenPGP provides a reliable method of authentication and encryption, it is also not unbreakable. OpenPGP can be vulnerable to many different types of attacks and weaknesses, including poor implementation, hardware or software compromise, fake keys and more. It is important to realize that OpenPGP provides significant, but not unbreakable security.
At 180 pages and priced at $24.95, PGP & GPG: Email for the Practical Paranoid is an excellent book that shows the end-user in an easy to read and often entertaining style just about everything they need to know to effectively and properly use PGP and OpenPGP.
For those that want to save money and perhaps save a few trees, the free documentation that comes along with the product is similarly worth reading.
You can purchase PGP & GPG: Email for the Practical Paranoid from bn.com.
Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
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A New Core Class in College? (Score:5, Insightful)
So basically 99.9% of users online today.
Re:A New Core Class in College? (Score:2, Interesting)
So basically 99.9% of users online today.
You're missing at least one 9, I figure. If there are a billion folks [more or less] online...
1,000,000,000; 1 in 1000 would mean that 1,000,000 people online have more than a notion of how public-key cryptography works.
I guess I could believe that there are 10K or more, but I certainly think there are fewer than 100K.
Re:A New Core Class in College? (Score:3, Insightful)
What level of understanding are we talking here? I understand how public/private key encryption works well enough to use it securely, and it's not that hard to grasp. I imagine a significant portion of Slashdotters understand it as well. With almost 1,000,000 accounts, if only one in ten of us got it, there's your 100K.
Now if you mean understand as in "could create a secure public key algorithm," then OK, I see your point.
So What Does It Mean? (Score:5, Insightful)
This statement may indeed be true. And yet, 98 out of 100 people on the street would have no idea what PGP is. What does that say about software encryption programs.
No one knows, no one cares and very few have been affected by their ignorance.
Re:So What Does It Mean? (Score:5, Insightful)
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Re:So What Does It Mean? (Score:5, Interesting)
The US government, of course, didn't want this future to come about and put roadblocks in place to prevent it. So, today we have phoney email scams and unencrypted personnel data that gets scattered to the winds on unsecured government and private sector computers. Encrypt your email? Why you must be doing something illegal!
Dennisk
Parent
Re:So What Does It Mean? (Score:2)
Re:So What Does It Mean? (Score:3, Informative)
Re:So What Does It Mean? (Score:5, Funny)
Parent
Re:So What Does It Mean? (Score:2)
So what's the problem? I always thought obscurity was a key to security...
more importantly... (Score:2)
This statement may indeed be true. And yet, 98 out of 100 people on the street would have no idea what PGP is. What does that say about software encryption programs.
So then, what does this say about Slashdot readers?
Should rename the book (Score:5, Interesting)
title soon to become "PGP & GPG: encryption for the practical suspicious target of the homeland security dept."
Re:Should rename the book (Score:2)
(Caveat: I'm the author of the book)
I thought about such a subtitle, but the book is not just for the average person. Rich Americans can read it, too.
==ml
Re:Should rename the book (Score:4, Funny)
Parent
Pretty Poor Privacy (Score:2, Interesting)
Instead, I found my holy grail of encryption in Truecrypt (http://truecrypt.org )which simply has rocked for the longest time (I'm in no way associated with it). Its free, and as far as I'm concerned as far as free encryption tools go, nothing can touch it, esp if you use one of the double pass encyption methods down the list, and don't label your volumes as truecrypt volumes or keep
Re:Pretty Poor Privacy (Score:3, Funny)
>I don't know any compgeek that uses PGP, or anyone that uses it to encrypt their mail.
-----BEGIN PGP MESSAGE-----
Version: PGP for Personal Privacy 6.0
qANQR1DBwU4DA/vEixf2Zr4QB/95c5uv6mCv4yYel3qStih a bGzW7Ekfi4STPs1T CJf/fgp3S0SHUFmCgJXL4QNdkoo37wdVD/4v5xWWj7tXPfA2KQ 8bYueHIWp8QXIx TIxxRIQhw/69WXT/RAAtRBdvFPfucphQZ8xSxOc6gPlMYnPOVC PjXqXaZcZXwk8R Cv9yICy+S8ipGiGb3miPOfvqv/FAOT/uVCHv/VGrVJhDD29xfM 7TWk25LLXlbQW5 pOjgO30DNdbdhQMdsOSmQXTQdRDJDjbwQeWWk3CFZtpLmlbjXL U0hvZ7PtAGlQKh iIboJl+HM+jsEtHurqmgXR1
Re:Pretty Poor Privacy (Score:2)
Personally, if I have some data I want secured and backed up, I use duplicity, and that backs up and encrypts the data using GPG. If I want to save a note for myself somewhere, I email it to myself, encrypted. The VAST majority of my email is GPG signed so that recipients know that the mail came from me.
It's really useful in the geek community. Trust me, have a play - it's a great
Re:Pretty Poor Privacy (Score:3, Informative)
encrypt your data in a small volume and attach it as a file to who you want to send it to...
How would they know the passphrase to open your attachment? That's the whole point of the public/private key system.
Slashdot and Public Keys (Score:5, Informative)
Re:Slashdot and Public Keys (Score:2)
To be honest, this field reminds me of a common situation I run into when developing
I have never seen this used on Slashdot
Re:Slashdot and Public Keys (Score:2)
>does anyone know where you go to pick up other users' keys?
There are many public keyserves to search. PGP will automatically search them for unknown keys, if so configured.
Mil Grade Crypto... IS defined :-P (Score:5, Informative)
Ahem, reference http://www.nsa.gov/ia/industry/crypto_suite_b.cfm [nsa.gov]
While Suite A is classified, Suite B, specifically AES, is specifically mentioned as being suitable for up to TOP SECRET info.
Military grade is not a useless term, as it is therein defined.
HOO-AH!
Re:Mil Grade Crypto... IS defined :-P (Score:2)
Re:Mil Grade Crypto... IS defined :-P (Score:3, Insightful)
For that particular application, absolutely. And if I find myself in a similar situation, then I can safely do the same since, if the military feels that's sufficient to protect their likely-more-important data, then I probably can, too.
Is this really that difficu
S/MIME (Score:5, Interesting)
If people CHOOSE to trust a PKI, S/MIME works WAY better than PGP because key distribution is much easier. If they don't want to do a PKI, they can still trust individual certificates, just like PGP. They can verify certificates by reading thumbprints over the phone, if they like.
Basically, S/MIME can do everything PGP/MIME can do except the "web of trust." And WoT is just WAY too much work for 99.9% of the population. PGP will eventually vanish.
Re:S/MIME (Score:2)
Re:S/MIME (Score:3, Insightful)
> common form of email security on the Internet.
If this is going to happen then S/MIME has yet some way to go first. Reality is that I see S/MIME only ever "used" by corporate minions. I put quote marks around "used", because I have yet to receive anything more than a signed mail. On the other hand there are ISPs and domain registrars who work with PGP - you can give them your public key and do business like that.
Have you noticed how
Outlook plugin? (Score:3, Insightful)
What I'd like to see is an Outlook plugin (or OExpress) that does the following. (Please note that I wrote O/OE because they are the major players)
* GPG included to make it easy for the user. Just one install for the whole package.
* Automatically create keypair during installation
* Default option to keep passphrase cached (not safe, yes I know, I know)
* Automatically decrypt/sigcheck all incoming emails
* Automatically encrypt/sign all outgoing mails.
* Attach the pubkey to all outgoing mails where the address isn't in my keyring.
* Automatically (just ask for password confirmation or something) addition of incoming pubkeys to my keyring.
* GPL
* The people who got the pubkey would also get a link to where to download the plugin.
I'm sure someone can expand this list quite a bit and I'm sure I forgot half of what I wanted to put on that list, but it's a start anyway.
Anyone care to write such a plugin? Or is there one already that I don't know of?
I do think that if there was something to that effect that you would see a spike in encrypted emails going across the globe.
I used to encrypt/sign everything but since I was the only one using pgp/gpg it was kind of pointless.
Re:Outlook plugin? (Score:3, Informative)
It does the first two, and the third - it does cache passphrases for short periods of time. I don't know off the top of my head how to change the cache duration, but there should be a config option somewhere.
Sending encrypted or signed email is just a matter of two toggles in a toolbar on every email - you should be able to change a setting somewhere so they always default to on (right now they defa
I wish security were more accessible to the masses (Score:5, Funny)
Just the other day I saw the following on the website of an author selling her own book directly:
Sigh...
Re:I wish security were more accessible to the mas (Score:4, Interesting)
Just as a an example, I set up a shopping cart of the type I mentioned and they thought it was the mutts nutz until I showed them that I was receiving both parts of the credit card numbers by email at a private email account. Even then I don't think they thought it was a problem. I left shortly afterwards.
I wonder whose harvesting those numbers now...
BTW, I deleted that shopping cart, so I am not guilty of abusing the system. It was done to prove a point. [slashdot.org]
Parent
Re:I wish security were more.. (Score:3, Interesting)
All-in-all, I think it's a practical down-to-earth simple solution. Seriously, don't laugh just because it's not technical enough for you.. So while you're busy being a tech-snon, the world will be busy getting stuff done. This works; for now.
Re:I wish security were more accessible to the mas (Score:2, Insightful)
http://www.rncca.com/ [rncca.com]
why they have a password is beyond me when they list the password on the site?
Advice for me (Score:3, Funny)
Re:what the... (Score:4, Funny)
Parent
But why do a "difficult" Google search ... (Score:2)
From the ninth paragraph:
The difference between them is that PGP is a commercial piece of software, GPG (Gnu Privacy Guard) is open source,
Re:But why do a "difficult" Google search ... (Score:2)
Re:what the... (Score:2)
Re:what the... (Score:2)
Anon has a point though (Score:2, Insightful)
X.509 requires a CA. (Score:5, Informative)
GPG/PGP are asymmetric cryptosystems that don't rely on PKI infrastructure, just per-user public/private keypairs. Not enterprise friendly but they can be used to bootstrap a trusted online relationship.
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Re:X.509 is better (Score:4, Insightful)
Aside from the fact that noone should use outlook, I read up a tiny bit on X.509. According to Wikipedia, X.509 uses signed certificates from CAs, meaning you have to PAY, and store your certificate with a "trusted company". Not only is this horrible for paranoids who wouldn't trust Verisign, but the US Gov. could subpoena your information from these companies, rendering your encryption useless (against the government).
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Re:X.509 is better (Score:5, Informative)
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Re:X.509 is better (Score:5, Informative)
That is obvious.
According to Wikipedia, X.509 uses signed certificates from CAs, meaning you have to PAY,
No, you can set up your own CA (for free) with openssl. And in fact, you don't need a CA at all. You can use your own certificates that aren't signed by anyone, just like PGP/GPG. In fact, the underlying math (public-key cryptography) is exactly the same as PGP/GPG.
and store your certificate with a "trusted company".
Store your certificate? Bullshit. You send the CA a certificate signing request. They sign it, and send it back to you. The certificate is useless without your private key, and the private key doesn't leave your possession. Decryption can only be done with the private key. So don't lose it.
Not only is this horrible for paranoids who wouldn't trust Verisign,
You don't need to trust Versign for X.509 to work. The only time you need to trust Versign (or any other CA) is to identify the cert of someone you never met. How do you know that a cert really belongs to the person? Verisign (or some other CA) signed the certificate. How do you know if a PGP key really belongs to someone you never met? Someone signed it.
But do you trust the signer? That question occurs with certificates and PGP keys.
but the US Gov. could subpoena your information from these companies, rendering your encryption useless (against the government).
Even if the US Gov't seizes all of verisign's info, that won't help them break your cryptography, since the private key (see above) never left your possession and Verisign never had it.
It's one thing to be paranoid, it's another thing to be an idiot. Understand how cryptography works before you start to rant & rave.
Frankly, if the US Gov't really, really wants to break your encryption, they'll bug your computer, or your house, or call in the NSA, or send in the Marines.
Parent
Re:X.509 is better (Score:5, Insightful)
The simplicity of X.509? Is completly the other way around. PGP is simple
You probably never implemented a corporate PKI infrastructure. I myself love PKI (it's a freeking miracle I got married, I know) and have implemented or at least contributed in implementing several PKI's over the years. Simplicity is definitely not the first thing that comes to mind. Things like OCSP and CRL's you need to check the validity of a key, basically everything around issuing keys, key-escrow etc. it is al pretty complicated. Not nescecairly the theory, but the actual implementation and integration. Plus not to mention expensive. And don't even get me started on the legal side of it, the contracts you need, the legal requirements, webtrust etc.etc.. Brrrrrrr.
PKI is cool, has a lot of potential etc. Put it's not simple in anyway. Microsoft may make it look simple (did I just say that?), by basically "trusting" loads of CA's defaultly but how much is that trust worth exactly? Not much in my eyes. Oke, the encryption during transit... that should be ok. But is the signer of that email really who he says he is?
Between me, my friends and my colleguae's we use GPG. Bunch of my friends are on Mac's like me others are on Linux or BSD flavored machines. Some even use Windows. I don't even know al the plug-ins everyone uses. Hell, I don't know the name of mine. It integrated with Apple Mail and I just press the buttons etc, type in my passphrase and it works. Simple. Plus the keys I trust, I explicitly trusted by hand. Basically this kind of trust is loads better then accepting any mail certificate issued by the Verisigns of the world.
Here is the Mac link: http://macgpg.sourceforge.net/ [sourceforge.net] . Loads of GUI GPG tools.
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X.509 is worse (Score:4, Informative)
John: Cool. Here's mine.
Et voila - we can now start sending private messages back and forth (neglecting man-in-the-middle issues with the key exchange that can be trivially avoided with a single phone call or in-person meeting). Notice the missing step: neither of us paid Verisign or another CA for the privilege of saying "Hey, wanna go to lunch?" in private.
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Re:X.509 is worse (Score:2)
Re:X.509 is better (Score:2)
Re:Obligatory (Score:2)
Re:paranoia? (Score:5, Insightful)
* They've coerced the author to build in a backdoor (a la clipper).
* They've spent enough billions on serious hardware that they can brute-force it in a reasonable time.
* They've got some very clever mathematician to figure out a viable attack.
I think you can safely scratch #1, while also safely assuming #2. The trick is how timely, and how much encrypted traffic there is overall. If you or your message has been flagged as a high priority decrypt, then they're likely to throw a lot of crunch at it.
However, if you're not flagged and more people start to use encryption, you're more likely to get lost in the noise.
Your #3, I have no idea. I don't really have enough math knowledge to have a good grasp on the difficulties such a mathematician would face.
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