Stuff I have written/presented
Submitted by gwolf on Mon, 04/27/2015 - 22:24
That's all I need to enjoy the best best party ever.
Oh! Shall I mention that we got a beautiful present for the kids from our very dear DebConf official Laminatrix! Photos not yet available, but will provide soon.
Submitted by gwolf on Sun, 04/26/2015 - 23:34
(No, I'm not talking about a future Ubuntu release... After all, what kind of weird animal would a weekend be?)
This weekend we took the kids outside for the first time (not counting, of course, visits to the pediatrician). We were quite anxious... Of course, they were born somewhat under weight and at 7½ months of gestation. But this Saturday we feelt adventurous, and took the kids out for a day among people!
It might not sound like a big deal, but... Well, we took a not such beautiful or scenic route: We took them to the supermarket, and had a small lunch out. For the first time in the already two months they have been with us.
Dinner with friends at home, having a very good time, and –as expected– a... Very hard night for us. All that excitement had the babies very nervous.
Today –again, for the first time– we took the children out to visit some friends of ours. Again, it was great, they behaved very nicely, and were lovely all around.
Lets see what this night holds in place for us.
Anyway, with them growing slowly but steadily... We are very happy, thankful parents. For the first time since Regina is with me in Mexico, this time we decided we would not have a birthday party (yes, I'm 30 minutes away from being 39 year old). I cannot imagine a fuller, better celebration than what we are having. This two babies are the real event in our lives.
Oh... And by the way, this weekend also saw the release of a great new Debian release: Debian 8, codenamed Jessie. Thanks, folks, for such a great birthday present ;-) For reasons that should by now be obvious, I wasn't able to go to either of the release parties I knew of in Mexico City (even one of them was ~500m from home!)
Submitted by gwolf on Wed, 04/08/2015 - 11:47
Once again, on March 11 I had a great guest to save me some work and give a talk at my class! This time it was César Yáñez, and he talked about memory management algorithms, emphasizing on ARC.
Thanks a lot!
Submitted by gwolf on Sun, 03/15/2015 - 17:49
My good friend Felipe Esquivel is driving a crowdfunded project: the first part of the "Natura" short film. I urge every reader of my blog to support Felipe's work!
Not only that: It might be interesting for my blog's readers that a good deal of the work of Chamán Animation's work (of course, I am not qualified to state that "all of" their work — But it might well be the case) is done using Free Software, specifically, using Blender.
So, people: Go look at their work. And try to be part of their work!
Submitted by gwolf on Sat, 02/28/2015 - 08:26
Welcome little babies!
Yesterday night, we entered the hospital. Nervous, heavy, and... Well, would we ever be ready? As ready as we could.
A couple of hours later, Alan and Elena Wolf Daichman became individuals on their own right. As is often the case in the case of twins, they were brought to this world after a relatively short preparation (34 weeks, that's about 7.5 months). At 1.820 and 1.980Kg, they are considerably smaller than either of the parents... But we will be working on that!
Regina is recovering from the operation, the babies are under observation. As far as we were told, they seem to be quite healthy, with just minor issues to work on during neonatal care. We are waiting for our doctors to come today and allow us to spend time with them.
And as for us... It's a shocking change to finally see the so long expected babies. We are very very very happy... And the new reality is hard to grasp, to even begin understanding :)
PS- Many people have told me that my blog often errors out under load. I expect it to happen today :) So, if you cannot do it here, there are many other ways to contact us. Use them! :)
Submitted by gwolf on Fri, 02/06/2015 - 12:51
I would expect brute-force login attacks to be more common. And yes, at some point I got tired of ssh scans, and added rate-limiting firewall rules, even switched the daemon to a nonstandard port... But I have very seldom received an IMAP brute-force attack. I have received countless phishing scams on my users, and I know some of them have bitten because the scammers then use their passwords on my servers to send tons of spam. Activity is clearly atypical.
Anyway, yesterday we got a brute-force attack on IMAP. A very childish atack, attempted from an IP in the largest ISP in Mexico, but using only usernames that would not belong in our culture (mosty English firstnames and some usual service account names).
What I find interesting to see is that each login was attempted a limited (and different) amount of times: Four account names were attempted only once, eight were attempted twice, and so on — following this pattern:
1 • 2 •• 3 •• 4 ••••• 5 ••••••• 6 •••••• 7 ••••• 8 •••••••• 9 ••••••••• 10 •••••••• 11 •••••••• 12 •••••••••• 13 ••••••• 14 •••••••••• 15 ••••••••• 16 •••••••••••• 17 ••••••••••• 18 •••••••••••••• 19 ••••••••••••••• 20 •••••••••••• 21 •••••••••••• 22 ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••
(each dot represents four attempts)
So... What's significant in all this? Very little, if anything at all. But for such a naïve login attack, it's interesting to see the number of attempted passwords per login varies so much. Yes, 273 (over ¼ of the total) did 22 requests, and another 200 were 18 and more. The rest... Fell quite shorter.
In case you want to play with the data, you can grab the list of attempts with the number of requests. I filtered out all other data, as i was basically meaningless. This file is the result of:
Submitted by gwolf on Fri, 01/02/2015 - 12:25
Having seen the end of December and the beginning of January, this is the time of year where we say "Happy new year!"
But this is a very interesting new year: We have also went past our much announced deadline for the <2048 bit keys to be removed from the Debian keyrings. And yes, our highly efficient keyring-maint team managed to deliver on the promised time — And, I'd say, with much success. Lets see the numbers — Only before that, refer to Jonathan's mail to debian-devel-announce for further, fuller information.
So, first of all, how do overall numbers look? Just remember, the following are not the number of DDs, just the number of active keys. That is, the holders to the 252 DD and 35 DM keys we removed are still valid Debian Developers/Maintainers, but have to get a new key accepted to perform many of their tasks in the project.
The graph above shows the sharp change between tags 2014.12.31 and 2015.01.01. But my definition of success is that we managed to get the number down to just 252+35=287 from what we had back in August, when we did our DebConf presentation and started the aggressive push: 490 DD keys and 49 DM keys. Since then, 34 DDs requested their retirement, becoming emeritus, and practically all of the rest managed to get their key transition done!
So, lets go again easiest-to-hardest. First, the Non-uploading Debian Developers keyring:
As this is the newest keyring in existence, and is also the smallest one, we were already without <2048 keys since 2011. Nothing to see, move along.
Then, as for the Debian Maintainers:
We did have a sensible migration from weaker to stronger keys, but it was not as sharp as I'd have liked. That makes sense, after all, since DMs have less involvement and compromise in the project in regard to DDs. So, we only processed 15 DM keys since August, which is almost a third of the keys we needed to process to reach the ideal 100% migration.
Now, as for our biggest and oldest keyring, and the one that denotes more project involvement, here is the graph for the uploading Debian Developers:
And yes, here you can see the sharp turn we saw in the second half of this year: By DebConf time, we were happy because the red and yellow lines had just crossed. But we were still sitting at 490 DD keys needing to be migrated. Half of the DD keys (compared to almost a fourth for the DM keys).
I'm almost sure we anticipated in our presentation (I know, I should check the video) that, by January 1st, we would have to retire around 300 keys. And I'm very, very happy and proud that we managed to get the number down to 252.
And, yes, people leave things to the end: We already have some more pending requests in the Request Tracker to introduce new keys for our fellow friends who were disabled. We will be working to make keyring pushes more frequent than our usual monthly uploads until requests go back to a sane level.
So, if everything runs smoothly, this will probably be the last of my posts in this regard. This has been quite an interesting (and exhausting!) experience!
Submitted by gwolf on Wed, 12/24/2014 - 11:49
I have long wanted to echo Gregor's beautiful Debian Advent Calendar posts. Gregor is a dear project member and a dear friend to many of us Debianers, who has shown an amount of stamina and care for the project that inspires everybody; this year, after many harsh flamefests in the project (despite which we are moving at a great rate towards a great release!), many people have felt the need to echo how Debian –even as often seen from the outside as a hostile mass of blabbering geeks– is actually a great place to work together and to create a deep, strong social fabric — And that's quite probably what binds the project together and ensures it will continue existing and excelling for a long time.
As for the personal part: This year, my Debian involvement has –once again– reduced. Not because I care less about Debian, much to the contrary, but because I have taken several responsabilities which require my attention and time. Technically, I'm basically maintaining a couple of PHP-based packages I use for work (most prominently, Drupal7). I have stepped back of most of my DebConf responsabilities, although I stay (and will stay, as it's an area of the project I deeply enjoy doing) involved. And, of course, my current main area of involvement is keyring-maint (for which I have posted here several status updates).
I have to say that we expected having a much harder time (read: Stronger opposition and discussions) regarding the expiry of 1024D keys. Of course, many people do have a hard time connecting anew to the web of trust, and we will still face quite a bit of work after January 1st, but the migration has been a mostly pleasant (although clearly intensive) work. Jonathan has just told me we are down to only 306 1024D keys in the keyring (which almost exactly matches the "200-300" I expected back at DC14).
Anyway: People predicting doomsday scenarios for Debian do it because they are not familiar with how deep the project runs in us, how important it is socially, almost at a family level, to us that have been long involved in it. Debian is stronger than a technical or political discussion, no matter how harsh it is.
And, as a personal thank-you: Gregor, your actions (the GDAC, the RC bug reports) inspire us to stay active, to do our volunteer work better, and remind us of how great is it to be a part of a global, distributed will to Do It Right. Thanks a lot!
Submitted by gwolf on Tue, 12/23/2014 - 23:47
Much ink has been spilled lately (well, more likely, lots of electrons have changed their paths lately — as most of these communications have surely been electronic) on the effects, blame, assurance and everything related to the (allegedly) North Korean attack on Sony's networks. And yes, the list of components and affectations is huge. Technically it was a very interesting feat, but it's quite more interesting socially. Say, the not-so-few people wanting to wipe North Korea from the face of the Earth, as... Well, how did such a puny nation dare touch a private company that's based in the USA?
Of course, there's no strong evidence the attack did originate in (or was funded by) North Korea.
And... I have read very few people talking about the parallels to the infamous Stuxnet, malware written by USA and Israel (not officially admitted, but with quite a bit of evidence pointing to it, and no denial attempts after quite a wide media exposure). In 2010, this worm derailed Iran's nuclear program. Iran, a sovereign nation. Yes, many people doubt such a nuclear program would be used "for good, not for evil" — But since when have those two words had an unambiguous meaning? And when did it become accepted as international law to operate based on hunches and a "everybody knows" mentality?
So, how can the same people repudiate NK's alleged actions and applaud Stuxnet as a perfect weapon for peace?
Submitted by gwolf on Wed, 11/26/2014 - 10:49
On November 14, as a great way to say goodbye to a semester, a good friend came to my class again to present a topic to the group; a good way to sum up the contents of this talk is "everything you ever wondered about persistent storage".
As people who follow my blog know, I like inviting my friends to present selected topics in my Operating Systems class. Many subjects will stick better if presented by more than a single viewpoint, and different experiences will surely enrich the group's learning.
So, here is Rolando Cedillo — A full gigabyte of him, spawning two hours (including two hiccups where my camera hit a per-file limit...).
Rolando is currently a RedHat Engineer, and in his long career, he has worked from so many trenches, it would be a crime not to have him! Of course, one day we should do a low-level hardware session with him, as his passion (and deep knowledge) for 8-bit arcades is beyond any other person I have met.
Submitted by gwolf on Tue, 11/25/2014 - 00:41
The line of BASIC code that appears as the subject for this post is the title for a book I just finished reading — And enjoyed thoroughly. The book is available online for download under a CC-BY-NC-SA 3.0 License, so you can take a good look at it before (or instead of) buying it. Although it's among the books I will enjoy having on my shelf; the printing is of a very enjoyable good quality.
And what is this book about? Well, of course, it analizes that very simple line of code, as it ran on the Commodore 64 thirty years ago.
And the analysis is made from every possible angle: What do mazes mean in culture? What have they meant in cultures through history? What about regularity in art (mainly 20th century art)? How would this code look (or how it would be adapted) on contemporary non-C64 computers? And in other languages more popular today? What does randomness mean? And what does random() mean? What is BASIC, and how it came to the C64? What is the C64, and where did it come from? And several other beautiful chapters.
The book was collaboratively written by ten different authors, in a Wiki-like fashion. And... Well, what else is there to say? I enjoyed so much reading through long chapters of my childhood, of what attracted me to computers, of my cultural traits and values... I really hope that, in due time, I can be a part of such a beautiful project!
Submitted by gwolf on Fri, 11/21/2014 - 13:29
Almost two months ago I posted our keyring status graphs, showing the progress of the transition to >=2048-bit keys for the different active Debian keyrings. So, here are the new figures.
First, the Non-uploading keyring: We were already 100% transitioned. You will only notice a numerical increase: That little bump at the right is our dear friend Tássia finally joining as a Debian Developer. Welcome! \o/
As for the Maintainers keyring: We can see a sharp increase in 4096-bit keys. Four 1024-bit DM keys were migrated to 4096R, but we did have eight new DMs coming in To them, also, welcome \o/.
Sadly, we had to remove a 1024-bit key, as Peter Miller sadly passed away. So, in a 234-key universe, 12 new 4096R keys is a large bump!
Finally, our current-greatest worry — If for nothing else, for the size of the beast: The active Debian Developers keyring. We currently have 983 keys in this keyring, so it takes considerably more effort to change it.
But we have managed to push it noticeably.
This last upload saw a great deal of movement. We received only one new DD (but hey — welcome nonetheless! \o/ ). 13 DD keys were retired; as one of the maintainers of the keyring, of course this makes me sad — but then again, in most cases it's rather an acknowledgement of fact: Those keys' holders often state they had long not been really involved in the project, and the decision to retire was in fact timely. But the greatest bulk of movement was the key replacements: A massive 62 1024D keys were replaced with stronger ones. And, yes, the graph changed quite abruptly:
We still have a bit over one month to go for our cutoff line, where we will retire all 1024D keys. It is important to say we will not retire the affected accounts, mark them as MIA, nor anything like that. If you are a DD and only have a 1024D key, you will still be a DD, but you will be technically unable to do work directly. You can still upload your packages or send announcements to regulated mailing lists via sponsor requests (although you will be unable to vote).
Speaking of votes: We have often said that we believe the bulk of the short keys belong to people not really active in the project anymore. Not all of them, sure, but a big proportion. We just had a big, controversial GR vote with one of the highest voter turnouts in Debian's history. I checked the GR's tally sheet, and the results are interesting: Please excuse my ugly bash, but I'm posting this so you can play with similar runs on different votes and points in time using the public keyring Git repository:
So, as of mid-October: 387 out of the 482 votes (80.3%) were cast by developers with >=2048-bit keys, and 95 (19.7%) were cast by short keys.
If we were to run the same vote with the new active keyring, 417 votes would have been cast with >=2048-bit keys (87.2%), and 61 with short keys (12.8%). We would have four less votes, as they retired:
So, lets hear it for November/December. How much can we push down that pesky yellow line?
Disclaimer: Any inaccuracy due to bugs in my code is completely my fault!
Submitted by gwolf on Thu, 11/20/2014 - 13:38
We have had terrible months in Mexico; I don't know how much has appeared about our country in the international media. The last incidents started on the last days of September, when 43 students at a school for rural teachers were forcefully disappeared (in our Latin American countries, this means they were taken by force and no authority can yet prove whether they are alive or dead; forceful disappearance is one of the saddest and most recognized traits of the brutal military dictatorships South America had in the 1970s) in the Iguala region (Guerrero state, South of the country) and three were killed on site. An Army regiment was stationed few blocks from there and refused to help.
And yes, we live in a country where (incredibly) this news by themselves would not seem so unheard of... But in this case, there is ample evidence they were taken by the local police forces, not by a gang of (assumed) wrongdoers. And they were handed over to a very violent gang afterwards. Several weeks later, with far from a thorough investigation, we were told they were killed, burnt and thrown to a river.
The Iguala city major ran away, and was later captured, but it's not clear why he was captured at two different places. The Guerrero state governor resigned and a new governor was appointed. But this was not the result of a single person behaving far from what their voters would expect — It's a symptom of a broken society where policemen will kill when so ordered, where military personnel will look away when pointed out to the obvious, where the drug dealers have captured vast regions of the country where are stronger than the formal powers.
And then, instead of dealing with the issue personally as everybody would expect, the president goes on a commercial mission to China. Oh, to fix some issues with a building company. That coincidentally or not was selling a super-luxury house to his wife. A house that she, several days later, decided to sell because it was tarnishing her family's honor and image.
And while the president is in China, the person who dealt with the social pressure and told us about the probable (but not proven!) horrible crime where the "bad guys" for some strange and yet unknown reason (even with tens of them captured already) decided to kill and burn and dissolve and disappear 43 future rural teachers presents his version, and finishes his speech saying that "I'm already tired of this topic".
Of course, our University is known for its solidarity with social causes; students in our different schools are the first activists in many protests, and we have had a very tense time as the protests are at home here at the university. This last weekend, supposed policemen entered our main campus with a stupid, unbelievable argument (they were looking for a phone reported as stolen three days earlier), get into an argument with some students, and end up firing shots at the students; one of them was wounded in the leg.
And the university is now almost under siege: There are policemen surrounding us. We are working as usual, and will most likely finish the semester with normality, but the intimidation (in a country where seeing a policeman is practically never a good sign) is strong.
And... Oh, I could go on a lot. Things feel really desperate and out of place.
Today I will join probably tens or hundreds of thousands of Mexicans sick of this simulation, sick of this violence, in a demonstration downtown. What will this achieve? Very little, if anything at all. But we cannot just sit here watching how things go from bad to worse. I do not accept to live in a state of exception.
So, this picture is just right: A bit over a month ago, two dear friends from Guadalajara city came, and we had a nice walk in the University. Our national university is not only huge, it's also beautiful and loaded with sights. And being so close to home, it's our favorite place to go with friends to show around. This is a fragment of the beautiful mural in the Central Library. And, yes, the University stands for "Viva México". And the university stands for "Peace". And we need it all. Desperately.
Submitted by gwolf on Sat, 11/08/2014 - 10:25
The following text is not mine. I'm copy-translating a text a dear friend of mine just wrote in Spanish, in Facebook. He writes far better than I do (much better than most people I have known). I am not also a great translator. If you can read Spanish, go read the original.
- Antonio Malpica. After what appears to be the bitter and sadly expected end of a sad, terrible, unbelievable collective social rupture we have lived for ~50 days.
And what comes next? How can it come? How can we expect it? I have no way to answer. We, the country's people, are broken.
Submitted by gwolf on Wed, 10/29/2014 - 15:47
Last Wednesday I had the pleasure and honor to have a great guest again at my class: José María Serralde, talking about real time scheduling. I like inviting different people to present interesting topics to my students a couple of times each semester, and I was very happy to have Chema come again.
Chema is a professional musician (formally, a pianist, although he has far more skills than what a title would confer to him — Skills that go way beyond just music), and he had to learn the details on scheduling due to errors that appear when recording and performing.
The audio could use some cleaning, and my main camera (the only one that lasted for the whole duration) was by a long shot not professional grade, but the video works and is IMO quite interesting and well explained.
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