Mon, 26 Dec 2011
Short key IDs are bad news (with OpenPGP and GNU Privacy Guard)
Summary: It is important that we (the Debian community that relies on OpenPGP through GNU Privacy Guard) stop using short key IDs. There is no vulnerability in OpenPGP and GPG. However, using short key IDs (like 0x70096AD1) is fundementally insecure; it is easy to generate collisions for short key IDs. We should always use 64-bit (or longer) key IDs, like: 0x37E1C17570096AD1 or 0xEC4B033C70096AD1.
TL;DR: This now gives two results: gpg --recv-key 70096AD1
Some background, and my two keys
Years ago, I read dkg's instructions on migrating the Debian OpenPGP infrastructure. It told me that the time and effort I had spent getting my key into the strong set wasn't as useful as I thought it had been.
I felt deflated. I had put in quite a bit of effort over the years to strongly-connect my key to a variety of signatures, and I had helped people get their own keys into the strong set this way. If I migrated off my old key and revoked it, I'd be abandoning some people for whom I was their only link into the strong set. And what fun it was to first become part of the strong set! And all the eyebrows I raised when I told people I was going meet up with people I met on a website called Biglumber... I even made it my Facebook.com user ID. So if I had to generate a new key, I decided I had better really love the short key ID.
But at that point, I already felt pretty attached to the number 0x70096AD1. And I couldn't come up with anything better. So that settled it: no key upgrade until I had a new key whose ID is the same as my old key.
That dream has become a reality. Search for my old key ID, and you get two keys!
$ gpg --keyserver pgp.mit.edu --recv-key 0x70096AD1 gpg: requesting key 70096AD1 from hkp server pgp.mit.edu gpg: key 70096AD1: public key "Asheesh Laroia <asheesh@asheesh.org>" imported gpg: key 70096AD1: public key "Asheesh Laroia <asheesh@asheesh.org>" imported gpg: no ultimately trusted keys found gpg: Total number processed: 2 gpg: imported: 2 (RSA: 1)
I also saw it as an opportunity: I know that cryptography tools are tragically easy to mis-use. The use of 32-bit key IDs is fundamentally incorrect -- too little entropy. Maybe shocking people by creating two "identical" keys will help speed the transition away from this mis-use.
A neat stunt abusing --refresh-keys
Thanks to a GNU Privacy Guard bug, it is super easy to get my new key. Let's say that, like many people, you only have my old key on your workstation:
$ gpg --list-keys | grep 70096AD1 pub 1024D/70096AD1 2005-12-28
Just ask GPG to refresh:
$ gpg --keyserver pgp.mit.edu --refresh-keys gpg: refreshing 1 key from hkp://pgp.mit.edu gpg: requesting key 70096AD1 from hkp server pgp.mit.edu gpg: key 70096AD1: public key "Asheesh Laroia <asheesh@asheesh.org>" imported gpg: key 70096AD1: "Asheesh Laroia <asheesh@asheesh.org>" not changed gpg: Total number processed: 2 gpg: imported: 1 (RSA: 1) gpg: unchanged: 1 gpg: no ultimately trusted keys found
You can see that it set out to refresh just 1 key. It did that by querying the keyserver for the short ID. The keyserver provided two hits for that query. In the end, GPG refreshes one key and actually imports a new key into the keyring!
Now you have two:
$ gpg --list-keys | grep 70096AD1 pub 1024D/70096AD1 2005-12-28 pub 4096R/70096AD1 2011-03-11
There is a bug filed in GNU Privacy Guard about this. It has a patch attached. There is, at the moment, no plan for a new release.
A faster attack, but nothing truly new
My friend Venkatesh tells me there is an apocryphal old Perl script that could be used to generate key ID collisions. Here in the twenty-first century, l33t h4x0rz like Georgi Guninski are trying to create collisions.
In May 2010, "halfdog" posted a note to the full-disclosure list that generates PGP keys with chosen short key IDs. I haven't benchmarked or tested that tool, but I have used a different tool (private for now) that can generate collisions in a similar fashion. It takes about 3 hours to loop through all key IDs on a dinky little netbook.
You don't have to use any of these tools. You can just rent time on an elastic computing service or a botnet, or your own personal computer, and generate keys until you have a match.
I think that it's easy to under-estimate the seriousness of this problem: tools like the PGP Key Pathfinder should be updated to only accept 64-bit (or longer) key IDs if we want to trust their output.
My offer: I will make you a key
I've been spending some time wondering: What sort of exciting demonstration can I create to highlight that this is a real problem? Some ideas I've had:
- Publish a private/public key pair whose key ID is the same as Phil Zimmerman's, original author of PGP
- Publish a private/public key pair whose key ID is the same as Werner Koch's, maintainer of GNU Privacy Guard
- Publish a set of public keys that mimic the entire PGP strong set, except where I control the private key of all these keys
The last one would be extremely amusing, and would be a hat-tip to some work discussed in Raph Levien's Google Tech Talk about Advogato.
For now, here is my offer: If you send me a request signed with a key in the strong set, I will create a 4096-bit RSA public/private key pair whose 32-bit key ID is one greater than yours. So if you are 0x517DD4E4 I will generate 0x517DD4E5.
I will post the keys here, along a note about who requested it, and instructions on how to import them into your keyring. (Note: I will politely decline to create a new key whose 32-bit key ID would create a collision; apologies if your key ID is just one away from someone else's.)
P.S. The prize for best sarcastic retort goes to Ian Jackson. He said, "I should go and create a lot of keys with your key ID. I'll set the real name to 'Not Asheesh Laroia' so everyone is totally clear about what is going on."
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Mon, 28 Nov 2011
The OOT Killer
Commitments require care, and recently I have been suffering from the delusion that making more commitments will make me more able to achieve them.
When overcommit reaches a certain point, the OOT (out of time) killer comes and reaps time from whatever it finds, often with disappointing consequences.
(See also: OOM Killer.)
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Sun, 23 Oct 2011
RFBP: Request for birthday present/package
There is a program that I love: bb.
bb is a demo of the famous ASCII Art library, aalib.
dT8 8Tb dT 8 8 Tb dT 8 8 Tb <PROJECT><PROJECT> dT 8 8 Tb dT 8 8 Tbbb has a serious bug, however: BB's "graphics" freeze when music starts.
Here's the issue.
So if your system (like most GNU/Linux systems) uses pulseaudio for sound, then bb is broken. That means every Ubuntu user and most desktop Debian users can't use it.
There are a few possible fixes, depending on where you'd want to solve the problem. If you just want bb to run on your own machine, without recompiling anything, you can adjust pulseaudio's configuration (in /etc/pulse/default.pa) to disable esound support. If you want to do that, just comment out this line:
We could also possibly patch bb so that it asks libmikmod not to use its esound "support."
I think the smarter thing to do is to adjust libmikmod. Since its esound support seems to be just plain broken, it should be removed. At very least, it should not be the default when ALSA output is available. There is a new upstream release of libmikmod, maybe the esound output is fixed.
In Debian, libmikmod is orphaned. When a package is orphaned, it means that a new person must step in and adopt the package. Debian packages need ongoing care and commitment to fix issues and make changes like this that benefit the users.
In this case, you'd need to understand some C and be willing to maintain a shared library. Maintaining a library in Debian requires attention to detail, but it is quite doable. Since you would be adopting an existing package, most of the work is already done for you. I would also be quite willing to answer questions. If you're not a Debian developer, I would happily sponsor uploads of this package into Debian so that the fixes are part of the distribution.
So: who will maintain libmikmod and fix bb? Could it be you?
It would make a really great birthday present if the amazing bb program worked in the next Debian release. Leave a comment if you have questions or are interested!
P.S. In a pinch, I can be convinced to maintain libmikmod myself, but I think this is a great opportunity for someone new to Debian to make a big difference.
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Fri, 02 Sep 2011
Debian bug squashing party at SIPB, MIT
(Photo credit: Obey Arthur Liu; originally on Picasa, license.)
Three weekends ago, I participated in a Debian bug squashing party. It was more fun than I had guessed!
The event worked: we squashed bugs. Geoffrey Thomas (geofft) organized it as an event for MIT's student computing group, SIPB. In this post, I'll review the good parts and the bad. I'll conclude with beaming photos of my two mentees and talk about the bugs they fixed.
So, the good:
The event was a success, but as always, there are some things that could have gone more smoothly. Here's that list:
Still, it turned out well! I did three NMUs, corresponding to three patches submitted for release-critical bugs by my two mentees. Those mentees were:
Jessica McKellar is a software engineer at
KspliceOracle and a recent graduate of MIT's EECS program. She solved three release-critical bugs. This was her first direct contribution to Debian. In particular:Jessica has since gotten involved in the Twisted project's personal package archive. Toward the end of the sprint, she explained, "I like fixing bugs. I will totally come to the next bug squashing party."
Noah Swartz is a recent graduate of Case Western Reserve University where he studied Mathematics and played Magic. He is an intern at the MIT Media Lab where he contributes to DoppelLab in Joe Paradiso's Responsive Environments group. This was definitely his first direct contribution to Debian. It was also one of the most intense command-line experiences he has had so far. Noah wasn't originally planning to come, but we were having lunch together before the hackathon, and I convinced him to join us.
Noah fixed #625177, a fails-to-build-from-source (FTBFS) bug in nslint. The problem was that "-Wl" was instead written in all lowercase in the debian/rules file, as "-wl". Noah fixed that, making sure the package properly built in pbuilder, and then spent some quality time with lintian figuring out the right way to write a debian/changelog.
That's a wrap! We'll hopefully have one again in a few months, and before that, I hope to write up a guide so that we run things even more smoothly next time.
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Wed, 17 Aug 2011
OpenHatch round two: the non-profit
For the past year or two, readers of asheesh.org (including those on Planet Debian) have been hearing on and off about OpenHatch, a project that began in Atlanta two summers ago.
The OpenHatch website has been a place to find out how new contributors can get involved in free software. Lately, I've discovered how much fun it is to help people get involved. I've also discovered oodles of enthusiasm for learning more about joining an open source project.
So I've been transitioning OpenHatch to be more of a non-profit and to work on more of those outreach events, and particularly I've been transitioning my life to support me (self-funded) working on that effort full-time for a year. If there's one thing I learned while creating a startup under incubation, it was how to save money.
The OpenHatch blog has the rest of the story. Here's a taste:
This change has been a long-time coming, and it's thanks to so many people who have given advice and feedback along the way. One special shout-out goes to Bradley Kuhn, who told me in March 2010 that OpenHatch should be a non-profit.
I hope you'll read more.
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Sun, 07 Aug 2011
Women, men, and accidentally being a jerk (at the Desktop Summit)
The first day of the Desktop Summit was yesterday, Saturday, August 6. I loved it and gave a presentation. There are two very different stories I can tell on the topic of gender equality in free software. I'll start with the bad.
It's pretty easy, in the U.S. at least, to get people of privilege to stop using terms that evoke centuries of oppression from slavery. It's harder to ask people to stop doing that to women. I'm writing this post to ask for that.
There were two different times that people I generally respect used words that historically have been used to hurt and minimize women.
"Cygnus Solutions is prostitutes." Dave Neary was delivering a talk (that I found impressively informative) called, "The cost of going it alone". When the talk covered the cost (in time and money) of getting your corporation's code into the community branch of an open-source project, he pointed out you could hire someone with the skills. Cygnus was the go-to company for that in the 1990s; to explain that Cygnus does not care who they work for, he said the sentence in bold.
"The OpenSuSE Build Service is a slut." I was at a party at a hackerspace last night. Someone who I admire for his work in free in free software, both technical and community, was joking with me about that no one should compile (or use) GTK. I riffed on the joke and remarked, "The OpenSuSE build service will build anything." He replied with the sentence in bold.
"Slut" and "prostitute" are terms that recall the objectification of women. They're terms that attempt to measure a woman's worth as a sex object.
It's not nice to the many women in attendance to bring that up.
You might not have thought this through. You might want to read one woman's take "On Sluts, Rape, and Fuckery". Give it a read.
Then, give it a rest.
The thing is, this matters all the time. That's why I have to call you two out on it.
Now for the happy story.
While watching the Desktop Summit's intern showcase, I was floored.
One hacker implemented Off-The-Record instant messaging for Telepathy. Another implemented pluggable back-ends for Getting Things GNOME, a task manager. I heard about overwhelming documentation and usability improvements to GNOME mainstays Cheese and Anjuta. In a short summer, these students made huge changes.
For most of them, this was the first time they delivered any sort of presentation. Every single talk was delivered in earnest and enthusiasm. They told us about the work they had done and what might happen in the future.
The other remarkable thing about the intern presentations was the demographics. I didn't keep count, but it seemed like as many women as men presented. We heard about hugely-important changes to documentation, code, and usability. People from central Europe, South Asia (yay), and Brazil took the stage.
I hope that is the future of free software.
There are two things I want to see for our community.
I want to know that people are respected and not reminded of centuries of oppression.
I also want to see our community grow in size and diversity.
I treat these issues as separate. We should choose respectful words when we speak not because we want more women to show up, but because it part of the expectation of decency that we should be able to expect from each other.
And I failed the community when I did not make it clear there and then that this kind of language is not okay with me. It took me a day to understand this failure, so here I am writing this blog post.
P.S. Thanks to Karen Rustad for her feedback while writing this post.
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Wed, 03 Aug 2011
I'm speaking at the Desktop Summit
Actually, I'm speaking there!
In two days, I'm going to be in Berlin talking about how to Get new contributors (and diversity) through outreach.
It shares a title with the talk I gave at PyCon, and I expect it will be similar. There are some points I will improve on, and some new pieces to cover:
In high school, I used to read the Dot daily. I was surprised and thrilled to see that they chose to list my talk in their announcement of the summit.
If you'll be there, too, let me know! Let's hang out.
And if you want to work one-on-one(-ish) on helping your project improve diversity or outreach, I will be in Berlin until August 14, and extremely happy to spend time with people.
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Wed, 13 Jul 2011
Open Source Bridge 2011: they love me (and gave me a scarf)!
On Friday, June 24, the last day of Open Source Bridge, I won a scarf! It says, "Open Source Citizen."
I wasn't the only one. The attendees nominated people who "made an extra effort to help others and share their knowledge," and the conference committee chose the three people they felt exemplified this. The winners were Sumana Harihareswara, Igal Koshevoy, and me.
In case you don't know Sumana, she's the new Wikimedia Volunteer Development Coordinator, a friend, and a commenter here at Asheeshworld. In the photo of her and her new scarf, you can also see Ward Cunningham. I suggest reading her wrap-up about the conference, and checking out the notes from her talk.
I haven't met Igal, but I've learned he's a fixture of the Portland tech scene. He's user number one on opensourcebridge.org and one of the original contributors to calagator, the most important event calendar in the Portland tech world. That's just a brief summary; follow him on Twitter to keep in touch.
I started the conference a little shy, not wanting to introduce myself to people, so I hung out with Sumana. She talked to everyone she could find, and there I was standing next to her. On the first day, it was only because of Sumana's outgoingness that people knew who I was. On the second and third days, I was involved in two sessions: a panel on open source communities and a talk about the OpenHatch training missions.
I was extremely honored to be chosen. There were so many other spectacular people I met for the first time, like Valerie Aurora, Jacinta Richardson, Brian Aker, and Alex Linsker. These are all people with three crucial traits: they're extremely knowledgeable, friendly, and opinionated. I'm glad I had a chance to attend and meet them!
Photo credits: Thanks to Noah Swartz for the photo of me. Sumana's photo comes from her post to wikitech-l. Igal's comes from his Open Source Bridge user profile.
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Sun, 03 Jul 2011
How I feel about Google+ (not thrilled)
Image credit: Lake Shimmer by (nc-sa) cobalt123.
The beautiful photo above is what reflections should look like. If you don't like Google's shimmering +1 buttons, try the convenient AdBlock filter Tom Morris wrote. I also block this image.
I have been reading a lot about Google+. I'm sure a lot of people put a lot of hard work into it. Lots of people seem to enjoy using it and appreciate its features. For my part, right now, when I see Google+ mentioned, the smile vanishes from my face.
I just have a few thoughts.
It's anti-competitive. If you could ask Google, "How much for a shimmering +1 button next to every search result?" you would be laughed out of the room. But they managed to offer themselves that unique marketing opportunity. I know that (1) most regulators who see this anti-competitive behavior won't see it as an anti-trust violation, and (2) the damage is already done, and no retribution in the future can act fast enough to fix the unfair advantage Google gave itself in the Internet-mediated personal communication (and ad sales) markets.
The shimmering is distracting, making my online search experience worse. I know that Google is holding nothing back; they are willing to distract me from my intended use of Google in order to branch out their business. (If you haven't seen the shimmering +1 button, it's next to every web search result, and if you mouse over any part of the result, it does a wavy dance.)
The most-touted feature is a clone of Diaspora. This by itself is fine; software should help users by having the best features imaginable. But the enthusiasm I've seen within the free software community (like when I read about Google+ on Slashdot and Planet Debian) should at least recognize that Google "circles" are a clone of Diaspora's Aspects.
Centralization on the web feels like a personal attack. Corporations on the web are like unstoppable machines rolling us toward a future of corporate eavesdropping, central points of failure, and end-users sold en masse to advertisers. It enables a future of individual "platform owners" who can change the lived experience of untold hundreds of millions with tweaks that benefit their actual customers (the advertisers). There's not much I can do about that. I happen to take this personally: I am part of a small culture of people who run their own mail and web servers and understand the importance of software freedom. This is a part of my identity. I watch as its traces online vanish, replaced by something more efficient and terrifying. It makes me sad.
I'm probably going to end up using it despite all these pain points. That's how I know that I am being steamrolled. The reasons I have given above are not reasons to not use Google+. They're just reasons that I'm going to frown all the way to the address bar.
In weeks to months to years, the service will grow an enthusiastic userbase. At that point, personally, I'll have to make a choice between connecting with those people on their terms, or not staying in touch with them. Already, professionally, the idea has already come up on #openhatch that Google+ could help us reach people willing to contribute to open source. Are my gripes worth holding OpenHatch back, or worth isolating myself over? Probably not.
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Fri, 06 May 2011
I'm going to Libre Graphics Meeting 2011
This is just a quick note to say:
Next week, I am going to be at:
My goals for the conference:
I'm going to arrive in Montreal at 6:30am on Tuesday on an overnight Greyhound bus from Boston. So another goal:
If you want to say hi to me during the conference, email me and make sure we meet up!
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