Re: [tor-talk] Tor Browser Bundle: PGP encryption built-in?
On 2011-10-10, Arturo Filastò a...@globaleaks.org wrote: On 10/10/11 9:44 AM, Robert Ransom wrote: On 2011-10-10, Fabio Pietrosanti (naif) li...@infosecurity.ch wrote: is anyone evaluating whenever to include PGP encryption support into the default Tor Browser Bundle as a Firefox extension? No. I actually think it would be a great idea to include PGP encryption support into the browser. I remember discussing this with Jake some time ago of maybe in the future having a bundle for Thunderbird and enigmail. I don't see why it it a bad idea to move one step closer into that direction by including PGP in the TBB. Adding GPG to a web browser does not move us any steps closer to having a mail user agent audited and packaged for use with Tor. I looked at the implementation and: * FireGPG it's discontinued http://getfiregpg.org/s/install It also seems it was using a bad design practice for the IPC communications between various modules. * NPAPI based GPG is just released (by old FirePGP contributor) https://github.com/kylehuff/webpg-npapi Having a support for GPG encryption into a generic browser, with PGP operations usable from Javascript/XUL, could open a lot of improvements and opportunities to secure Webmail and other web applications. No. See https://tails.boum.org/bugs/FireGPG_may_be_unsafe/ , but beware -- I'm sure katmagic and I missed a few dozen attacks. Well that attack proposed there is pretty basic, I really think this is a useful idea and it should not be discarded with no thought. There are two attacks on that page. When I thought of the keyring-enumeration attack listed there, I hadn't heard of the plaintext-leak attack yet, so I thought that only FireGPG's API was dangerous, and then only to Tor users who might be trying to remain anonymous or pseudonymous. (I have since realized that I really don't want an attacker to be able to read my keyring, even if They know who I am already.) Then katmagic told us about the plaintext-leak attacks on FireGPG, and I thought ‘Oh crap, that's *scary*.’. And *then* I discarded the idea of GPG-in-a-browser. These are not attacks on easily-avoided flaws in FireGPG's implementation. These are attacks on FireGPG's *purpose* -- *any* browser extension that did what FireGPG was *designed* to do would be vulnerable to these attacks. The Mikes and katmagic are trying to come up with new designs that could, in theory, be implemented safely. In practice, if you try to let users enter text to be encrypted into something that looks like a web form, an attacker *will* find a way to fool users into entering their plaintext into something that JavaScript can read from (or intercept key-press events for...), because a web form can be made to look like your GPG plaintext-entry area. So the only option is to have users enter plaintext into something that is clearly a separate window, and clearly not under the control of any web page -- and that defeats most of the purpose of putting GPG in a browser. At http://globaleaks.org we'll most probably need such kind of support into the browser and we're wondering if this could accomodate a standard requirement of the Tor Project for the Tor Browser Bundle. No. I must also here disagree, but I think I am a bit biased . Anyways as I said, it would be of great use for people to be able to user PGP built into the browser, at least for sending encrypted email. It should not be implemented in a rush, but the gain that can be drawn from such a feature is not slim. The gain is slim compared to the difficulty of designing a secure GPG browser extension and implementing it securely. Auditing a real MUA for use with Tor would be less difficult and *far* more useful. Also, we don't have room left in TBB for a GPG distribution at the moment. Firefox and Qt are too bloated. Instead of having people download and install complicated software to send me and an encrypted message I can point them to the TBB and they are all set. Not at all a badi dea. It's a bad idea if an attacker is very likely to succeed at grabbing users' plaintexts. It would be also possible to easily make very simple XUL interfaces to handle basic PGP based file encryption operations, de-facto bundling a GPG client (with a Browser UI) into the TorBrowserBundle. This sounds reasonable, except for the parts about the XUL interface and the browser-based UI. It also sounds rather like GPG4Win, except for those parts. What do you think about it? No. Robert, why do you have to be so negative? FireGPG was dangerous because it worked as designed. You (GlobaLeaks) started by proposing to implement the same design (including the API) again. Now you've backpedaled to trying to find *some* set of features that will let you bolt GPG onto the side of a browser, for no reason that I can see other than that you are determined to not give up on putting GPG in a browser *somehow*, even if you can't integrate it
Re: [tor-talk] Tor Browser Bundle: PGP encryption built-in?
On 2011-10-10, Fabio Pietrosanti (naif) li...@infosecurity.ch wrote: is anyone evaluating whenever to include PGP encryption support into the default Tor Browser Bundle as a Firefox extension? No. I looked at the implementation and: * FireGPG it's discontinued http://getfiregpg.org/s/install It also seems it was using a bad design practice for the IPC communications between various modules. * NPAPI based GPG is just released (by old FirePGP contributor) https://github.com/kylehuff/webpg-npapi Having a support for GPG encryption into a generic browser, with PGP operations usable from Javascript/XUL, could open a lot of improvements and opportunities to secure Webmail and other web applications. No. See https://tails.boum.org/bugs/FireGPG_may_be_unsafe/ , but beware -- I'm sure katmagic and I missed a few dozen attacks. At http://globaleaks.org we'll most probably need such kind of support into the browser and we're wondering if this could accomodate a standard requirement of the Tor Project for the Tor Browser Bundle. No. It would be also possible to easily make very simple XUL interfaces to handle basic PGP based file encryption operations, de-facto bundling a GPG client (with a Browser UI) into the TorBrowserBundle. This sounds reasonable, except for the parts about the XUL interface and the browser-based UI. It also sounds rather like GPG4Win, except for those parts. What do you think about it? No. We're going to make some experiment in trying to build https://gitweb.torproject.org/torbrowser.git + GPG + https://github.com/kylehuff/webpg-npapi . Ugh. Robert Ransom ___ tor-talk mailing list tor-talk@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
Re: [tor-talk] Tor Browser Bundle: PGP encryption built-in?
On 10/10/2011 2:44 AM, Robert Ransom wrote: No. See https://tails.boum.org/bugs/FireGPG_may_be_unsafe/ , but beware -- I'm sure katmagic and I missed a few dozen attacks. You're correct - that is, the https site you link has an unsafe certificate, * per msg * in Firefox 7: tails.boum.org uses an invalid security certificate. The certificate is not trusted because the issuer certificate is not trusted. (Error code: sec_error_untrusted_issuer) Anyone else seeing same security msg? ___ tor-talk mailing list tor-talk@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
Re: [tor-talk] Tor Browser Bundle: PGP encryption built-in?
On Oct 10, 2011, at 2:48 PM, Joe Btfsplk wrote: On 10/10/2011 2:44 AM, Robert Ransom wrote: No. See https://tails.boum.org/bugs/FireGPG_may_be_unsafe/ , but beware -- I'm sure katmagic and I missed a few dozen attacks. You're correct - that is, the https site you link has an unsafe certificate, * per msg * in Firefox 7: tails.boum.org uses an invalid security certificate. The certificate is not trusted because the issuer certificate is not trusted. (Error code: sec_error_untrusted_issuer) Anyone else seeing same security msg? Yes, the tails developers decided not to pay the SSL mafia and got a certificate from cacert instead. Your browser probably isn't configured to trust cacert, so you get the warning. Alternatively, someone is really trying to mitm you - tough to know. Anyway, the sha1 fingerprint of the tails website should be E1 5D 87 49 7F A1 21 75 8B 6B 1A 85 DC EF 70 E1 C6 7C 82 57. Now good luck deciding whether you should trust my claim in this unsigned email, or what. Enjoy the trip through the rabbit hole. ___ tor-talk mailing list tor-talk@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
Re: [tor-talk] Tor Browser Bundle: PGP encryption built-in?
On 10/10/11 13:48, Joe Btfsplk wrote: tails.boum.org uses an invalid security certificate. Anyone else seeing same security msg? Well done, you've found the flaw in the PKI model. Julian -- 3072D/D2DE707D Julian Yon (2011 General Use) pgp.2...@jry.me signature.asc Description: OpenPGP digital signature ___ tor-talk mailing list tor-talk@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
Re: [tor-talk] Tor Browser Bundle: PGP encryption built-in?
On 10/10/11 9:44 AM, Robert Ransom wrote: On 2011-10-10, Fabio Pietrosanti (naif) li...@infosecurity.ch wrote: is anyone evaluating whenever to include PGP encryption support into the default Tor Browser Bundle as a Firefox extension? No. I actually think it would be a great idea to include PGP encryption support into the browser. I remember discussing this with Jake some time ago of maybe in the future having a bundle for Thunderbird and enigmail. I don't see why it it a bad idea to move one step closer into that direction by including PGP in the TBB. I looked at the implementation and: * FireGPG it's discontinued http://getfiregpg.org/s/install It also seems it was using a bad design practice for the IPC communications between various modules. * NPAPI based GPG is just released (by old FirePGP contributor) https://github.com/kylehuff/webpg-npapi Having a support for GPG encryption into a generic browser, with PGP operations usable from Javascript/XUL, could open a lot of improvements and opportunities to secure Webmail and other web applications. No. See https://tails.boum.org/bugs/FireGPG_may_be_unsafe/ , but beware -- I'm sure katmagic and I missed a few dozen attacks. Well that attack proposed there is pretty basic, I really think this is a useful idea and it should not be discarded with no thought. At http://globaleaks.org we'll most probably need such kind of support into the browser and we're wondering if this could accomodate a standard requirement of the Tor Project for the Tor Browser Bundle. No. I must also here disagree, but I think I am a bit biased . Anyways as I said, it would be of great use for people to be able to user PGP built into the browser, at least for sending encrypted email. It should not be implemented in a rush, but the gain that can be drawn from such a feature is not slim. Instead of having people download and install complicated software to send me and an encrypted message I can point them to the TBB and they are all set. Not at all a badi dea. It would be also possible to easily make very simple XUL interfaces to handle basic PGP based file encryption operations, de-facto bundling a GPG client (with a Browser UI) into the TorBrowserBundle. This sounds reasonable, except for the parts about the XUL interface and the browser-based UI. It also sounds rather like GPG4Win, except for those parts. What do you think about it? No. Robert, why do you have to be so negative? We're going to make some experiment in trying to build https://gitweb.torproject.org/torbrowser.git + GPG + https://github.com/kylehuff/webpg-npapi . Ugh. AAAaaarghhh! Robert Ransom - Art. ___ tor-talk mailing list tor-talk@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
Re: [tor-talk] Tor Browser Bundle: PGP encryption built-in?
On 10/10/2011 01:07 PM, Mike Perry wrote: The problem with a browser extension is that the very thing that makes it useful is what makes it so risky. A GPG plugin of any kind becomes a vector for all sorts of nasty web attacks that would have normally been stopped by the server, such as XSS, XSRF, and various sorts of webbugs. On top of that, you need to protect against XUL XSS (which yields arbitrary code exec), as well as the privacy issues of leaking side-channels about the existence of certain keys in an otherwise anonymous browsing session. The plug-in (basically, an API to GnuPG) should never be exposed to anything other than the extension that provides it; there should be a separation between the plug-in, and the web page. I spoke about this in my prior email that I believe was forwarded to this list, as I was not yet subscribed. I'm not sure exactly what the FireGPG author expects to gain my moving all of this stuff to NPAPI. A naive use of his NPAPI code could easily lead to an *increase* in the vulnerability surface, not a decrease. And that's even assuming he codes the NPAPI bits safely. I was never the author of FireGPG, I was a contributor to a specific module for FireGPG; My intention for moving to NPAPI is to make a more portable browser interface to GnuPG (FireGPG used an IPC library that was not portable to other browsers) that can be used on any browser/email client that supports NPAPI. A naive use of JS+XPCOM IPC library could equally (if not more so) compromise a system if used incorrectly. This is true for anything. Care must be given to these subjects regardless of the language/ tools used. The source of my NPAPI plugin is freely available for anyone to review, so you can see for yourself if I have coded the NPAPI bits safely, and I gladly accept bug reports! =c ) I think your first task is to find out exactly what this guy thinks he did wrong in JS+XPCOM, and why moving to a more complicated language like C++ will make it better, and not worse. I didn't write FireGPG, but I will say the first place FireGPG went wrong was when it directly queried users for their passphrase. This should be delegated to the gpg-agent and in my opinion should never be requested by the browser. I would argue that C++ is less complicated than JS+XPCOM, but we are getting into personal perception here... If he won't answer or won't tell you, stay the hell away from his code. Agreed. Feel free to ask me questions regarding the plug-in code and design decisions. I definitely agree that this doesn't make the idea not worth doing. Personally, I think it would be way easier and safer to devote the effort into securing Thunderbird for GPG and Tor so we could just bundle that, but I understand the benefits and appeal of having everything in the browser. Technically, webpg-npapi should work with thunderbird, as I believe it supports bundled NPAPI plug-ins. But man, tread with care. GPG-in-a-browser is like a minefield of killer beehives in a jungle filled with wild dogs. Oh yeah, and when the dogs bark, they shoot bees at you. Too true! Here is a link to the official source that I mentioned: https://github.com/kylehuff/webpg-npapi Please note; I am *not* advocating that my NPAPI plug-in be packaged into a Firefox extension for use with Tor. I was asked by a Tor-talk mailing-list user what I thought about the possibility of including it, and I made my concerns known. I have no dog in this fight, use the module or don't, it makes no difference to me. I will gladly assist in any changes that are deemed necessary in order to make it more secure, but otherwise I have nothing to do with it, so please don't misunderstand my response as anything other than an attempt to answer questions. ___ tor-talk mailing list tor-talk@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
Re: [tor-talk] Tor Browser Bundle: PGP encryption built-in?
Thus spake Arturo Filastò (a...@globaleaks.org): I actually think it would be a great idea to include PGP encryption support into the browser. I remember discussing this with Jake some time ago of maybe in the future having a bundle for Thunderbird and enigmail. I don't see why it it a bad idea to move one step closer into that direction by including PGP in the TBB. I think the enigmail vulnerability surface is way more manageable than an arbitrary webby one, though perhaps less useful. It also seems it was using a bad design practice for the IPC communications between various modules. * NPAPI based GPG is just released (by old FirePGP contributor) https://github.com/kylehuff/webpg-npapi Having a support for GPG encryption into a generic browser, with PGP operations usable from Javascript/XUL, could open a lot of improvements and opportunities to secure Webmail and other web applications. No. See https://tails.boum.org/bugs/FireGPG_may_be_unsafe/ , but beware -- I'm sure katmagic and I missed a few dozen attacks. Well that attack proposed there is pretty basic, I really think this is a useful idea and it should not be discarded with no thought. The problem with a browser extension is that the very thing that makes it useful is what makes it so risky. A GPG plugin of any kind becomes a vector for all sorts of nasty web attacks that would have normally been stopped by the server, such as XSS, XSRF, and various sorts of webbugs. On top of that, you need to protect against XUL XSS (which yields arbitrary code exec), as well as the privacy issues of leaking side-channels about the existence of certain keys in an otherwise anonymous browsing session. I'm not sure exactly what the FireGPG author expects to gain my moving all of this stuff to NPAPI. A naive use of his NPAPI code could easily lead to an *increase* in the vulnerability surface, not a decrease. And that's even assuming he codes the NPAPI bits safely. I think your first task is to find out exactly what this guy thinks he did wrong in JS+XPCOM, and why moving to a more complicated language like C++ will make it better, and not worse. If he won't answer or won't tell you, stay the hell away from his code. What do you think about it? No. Robert, why do you have to be so negative? I think Robert is negative because the idea just sets off all sorts of warning bells. I definitely agree that this doesn't make the idea not worth doing. Personally, I think it would be way easier and safer to devote the effort into securing Thunderbird for GPG and Tor so we could just bundle that, but I understand the benefits and appeal of having everything in the browser. But man, tread with care. GPG-in-a-browser is like a minefield of killer beehives in a jungle filled with wild dogs. Oh yeah, and when the dogs bark, they shoot bees at you. -- Mike Perry Mad Computer Scientist fscked.org evil labs pgptMR1FujzP6.pgp Description: PGP signature ___ tor-talk mailing list tor-talk@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
